File: | build/source/clang/lib/AST/ExprConstant.cpp |
Warning: | line 6059, column 57 Called C++ object pointer is null |
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1 | //===--- ExprConstant.cpp - Expression Constant Evaluator -----------------===// | |||
2 | // | |||
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | |||
4 | // See https://llvm.org/LICENSE.txt for license information. | |||
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | |||
6 | // | |||
7 | //===----------------------------------------------------------------------===// | |||
8 | // | |||
9 | // This file implements the Expr constant evaluator. | |||
10 | // | |||
11 | // Constant expression evaluation produces four main results: | |||
12 | // | |||
13 | // * A success/failure flag indicating whether constant folding was successful. | |||
14 | // This is the 'bool' return value used by most of the code in this file. A | |||
15 | // 'false' return value indicates that constant folding has failed, and any | |||
16 | // appropriate diagnostic has already been produced. | |||
17 | // | |||
18 | // * An evaluated result, valid only if constant folding has not failed. | |||
19 | // | |||
20 | // * A flag indicating if evaluation encountered (unevaluated) side-effects. | |||
21 | // These arise in cases such as (sideEffect(), 0) and (sideEffect() || 1), | |||
22 | // where it is possible to determine the evaluated result regardless. | |||
23 | // | |||
24 | // * A set of notes indicating why the evaluation was not a constant expression | |||
25 | // (under the C++11 / C++1y rules only, at the moment), or, if folding failed | |||
26 | // too, why the expression could not be folded. | |||
27 | // | |||
28 | // If we are checking for a potential constant expression, failure to constant | |||
29 | // fold a potential constant sub-expression will be indicated by a 'false' | |||
30 | // return value (the expression could not be folded) and no diagnostic (the | |||
31 | // expression is not necessarily non-constant). | |||
32 | // | |||
33 | //===----------------------------------------------------------------------===// | |||
34 | ||||
35 | #include "Interp/Context.h" | |||
36 | #include "Interp/Frame.h" | |||
37 | #include "Interp/State.h" | |||
38 | #include "clang/AST/APValue.h" | |||
39 | #include "clang/AST/ASTContext.h" | |||
40 | #include "clang/AST/ASTDiagnostic.h" | |||
41 | #include "clang/AST/ASTLambda.h" | |||
42 | #include "clang/AST/Attr.h" | |||
43 | #include "clang/AST/CXXInheritance.h" | |||
44 | #include "clang/AST/CharUnits.h" | |||
45 | #include "clang/AST/CurrentSourceLocExprScope.h" | |||
46 | #include "clang/AST/Expr.h" | |||
47 | #include "clang/AST/OSLog.h" | |||
48 | #include "clang/AST/OptionalDiagnostic.h" | |||
49 | #include "clang/AST/RecordLayout.h" | |||
50 | #include "clang/AST/StmtVisitor.h" | |||
51 | #include "clang/AST/TypeLoc.h" | |||
52 | #include "clang/Basic/Builtins.h" | |||
53 | #include "clang/Basic/TargetInfo.h" | |||
54 | #include "llvm/ADT/APFixedPoint.h" | |||
55 | #include "llvm/ADT/SmallBitVector.h" | |||
56 | #include "llvm/Support/Debug.h" | |||
57 | #include "llvm/Support/SaveAndRestore.h" | |||
58 | #include "llvm/Support/TimeProfiler.h" | |||
59 | #include "llvm/Support/raw_ostream.h" | |||
60 | #include <cstring> | |||
61 | #include <functional> | |||
62 | #include <optional> | |||
63 | ||||
64 | #define DEBUG_TYPE"exprconstant" "exprconstant" | |||
65 | ||||
66 | using namespace clang; | |||
67 | using llvm::APFixedPoint; | |||
68 | using llvm::APInt; | |||
69 | using llvm::APSInt; | |||
70 | using llvm::APFloat; | |||
71 | using llvm::FixedPointSemantics; | |||
72 | ||||
73 | namespace { | |||
74 | struct LValue; | |||
75 | class CallStackFrame; | |||
76 | class EvalInfo; | |||
77 | ||||
78 | using SourceLocExprScopeGuard = | |||
79 | CurrentSourceLocExprScope::SourceLocExprScopeGuard; | |||
80 | ||||
81 | static QualType getType(APValue::LValueBase B) { | |||
82 | return B.getType(); | |||
83 | } | |||
84 | ||||
85 | /// Get an LValue path entry, which is known to not be an array index, as a | |||
86 | /// field declaration. | |||
87 | static const FieldDecl *getAsField(APValue::LValuePathEntry E) { | |||
88 | return dyn_cast_or_null<FieldDecl>(E.getAsBaseOrMember().getPointer()); | |||
89 | } | |||
90 | /// Get an LValue path entry, which is known to not be an array index, as a | |||
91 | /// base class declaration. | |||
92 | static const CXXRecordDecl *getAsBaseClass(APValue::LValuePathEntry E) { | |||
93 | return dyn_cast_or_null<CXXRecordDecl>(E.getAsBaseOrMember().getPointer()); | |||
94 | } | |||
95 | /// Determine whether this LValue path entry for a base class names a virtual | |||
96 | /// base class. | |||
97 | static bool isVirtualBaseClass(APValue::LValuePathEntry E) { | |||
98 | return E.getAsBaseOrMember().getInt(); | |||
99 | } | |||
100 | ||||
101 | /// Given an expression, determine the type used to store the result of | |||
102 | /// evaluating that expression. | |||
103 | static QualType getStorageType(const ASTContext &Ctx, const Expr *E) { | |||
104 | if (E->isPRValue()) | |||
105 | return E->getType(); | |||
106 | return Ctx.getLValueReferenceType(E->getType()); | |||
107 | } | |||
108 | ||||
109 | /// Given a CallExpr, try to get the alloc_size attribute. May return null. | |||
110 | static const AllocSizeAttr *getAllocSizeAttr(const CallExpr *CE) { | |||
111 | if (const FunctionDecl *DirectCallee = CE->getDirectCallee()) | |||
112 | return DirectCallee->getAttr<AllocSizeAttr>(); | |||
113 | if (const Decl *IndirectCallee = CE->getCalleeDecl()) | |||
114 | return IndirectCallee->getAttr<AllocSizeAttr>(); | |||
115 | return nullptr; | |||
116 | } | |||
117 | ||||
118 | /// Attempts to unwrap a CallExpr (with an alloc_size attribute) from an Expr. | |||
119 | /// This will look through a single cast. | |||
120 | /// | |||
121 | /// Returns null if we couldn't unwrap a function with alloc_size. | |||
122 | static const CallExpr *tryUnwrapAllocSizeCall(const Expr *E) { | |||
123 | if (!E->getType()->isPointerType()) | |||
124 | return nullptr; | |||
125 | ||||
126 | E = E->IgnoreParens(); | |||
127 | // If we're doing a variable assignment from e.g. malloc(N), there will | |||
128 | // probably be a cast of some kind. In exotic cases, we might also see a | |||
129 | // top-level ExprWithCleanups. Ignore them either way. | |||
130 | if (const auto *FE = dyn_cast<FullExpr>(E)) | |||
131 | E = FE->getSubExpr()->IgnoreParens(); | |||
132 | ||||
133 | if (const auto *Cast = dyn_cast<CastExpr>(E)) | |||
134 | E = Cast->getSubExpr()->IgnoreParens(); | |||
135 | ||||
136 | if (const auto *CE = dyn_cast<CallExpr>(E)) | |||
137 | return getAllocSizeAttr(CE) ? CE : nullptr; | |||
138 | return nullptr; | |||
139 | } | |||
140 | ||||
141 | /// Determines whether or not the given Base contains a call to a function | |||
142 | /// with the alloc_size attribute. | |||
143 | static bool isBaseAnAllocSizeCall(APValue::LValueBase Base) { | |||
144 | const auto *E = Base.dyn_cast<const Expr *>(); | |||
145 | return E && E->getType()->isPointerType() && tryUnwrapAllocSizeCall(E); | |||
146 | } | |||
147 | ||||
148 | /// Determines whether the given kind of constant expression is only ever | |||
149 | /// used for name mangling. If so, it's permitted to reference things that we | |||
150 | /// can't generate code for (in particular, dllimported functions). | |||
151 | static bool isForManglingOnly(ConstantExprKind Kind) { | |||
152 | switch (Kind) { | |||
153 | case ConstantExprKind::Normal: | |||
154 | case ConstantExprKind::ClassTemplateArgument: | |||
155 | case ConstantExprKind::ImmediateInvocation: | |||
156 | // Note that non-type template arguments of class type are emitted as | |||
157 | // template parameter objects. | |||
158 | return false; | |||
159 | ||||
160 | case ConstantExprKind::NonClassTemplateArgument: | |||
161 | return true; | |||
162 | } | |||
163 | llvm_unreachable("unknown ConstantExprKind")::llvm::llvm_unreachable_internal("unknown ConstantExprKind", "clang/lib/AST/ExprConstant.cpp", 163); | |||
164 | } | |||
165 | ||||
166 | static bool isTemplateArgument(ConstantExprKind Kind) { | |||
167 | switch (Kind) { | |||
168 | case ConstantExprKind::Normal: | |||
169 | case ConstantExprKind::ImmediateInvocation: | |||
170 | return false; | |||
171 | ||||
172 | case ConstantExprKind::ClassTemplateArgument: | |||
173 | case ConstantExprKind::NonClassTemplateArgument: | |||
174 | return true; | |||
175 | } | |||
176 | llvm_unreachable("unknown ConstantExprKind")::llvm::llvm_unreachable_internal("unknown ConstantExprKind", "clang/lib/AST/ExprConstant.cpp", 176); | |||
177 | } | |||
178 | ||||
179 | /// The bound to claim that an array of unknown bound has. | |||
180 | /// The value in MostDerivedArraySize is undefined in this case. So, set it | |||
181 | /// to an arbitrary value that's likely to loudly break things if it's used. | |||
182 | static const uint64_t AssumedSizeForUnsizedArray = | |||
183 | std::numeric_limits<uint64_t>::max() / 2; | |||
184 | ||||
185 | /// Determines if an LValue with the given LValueBase will have an unsized | |||
186 | /// array in its designator. | |||
187 | /// Find the path length and type of the most-derived subobject in the given | |||
188 | /// path, and find the size of the containing array, if any. | |||
189 | static unsigned | |||
190 | findMostDerivedSubobject(ASTContext &Ctx, APValue::LValueBase Base, | |||
191 | ArrayRef<APValue::LValuePathEntry> Path, | |||
192 | uint64_t &ArraySize, QualType &Type, bool &IsArray, | |||
193 | bool &FirstEntryIsUnsizedArray) { | |||
194 | // This only accepts LValueBases from APValues, and APValues don't support | |||
195 | // arrays that lack size info. | |||
196 | assert(!isBaseAnAllocSizeCall(Base) &&(static_cast <bool> (!isBaseAnAllocSizeCall(Base) && "Unsized arrays shouldn't appear here") ? void (0) : __assert_fail ("!isBaseAnAllocSizeCall(Base) && \"Unsized arrays shouldn't appear here\"" , "clang/lib/AST/ExprConstant.cpp", 197, __extension__ __PRETTY_FUNCTION__ )) | |||
197 | "Unsized arrays shouldn't appear here")(static_cast <bool> (!isBaseAnAllocSizeCall(Base) && "Unsized arrays shouldn't appear here") ? void (0) : __assert_fail ("!isBaseAnAllocSizeCall(Base) && \"Unsized arrays shouldn't appear here\"" , "clang/lib/AST/ExprConstant.cpp", 197, __extension__ __PRETTY_FUNCTION__ )); | |||
198 | unsigned MostDerivedLength = 0; | |||
199 | Type = getType(Base); | |||
200 | ||||
201 | for (unsigned I = 0, N = Path.size(); I != N; ++I) { | |||
202 | if (Type->isArrayType()) { | |||
203 | const ArrayType *AT = Ctx.getAsArrayType(Type); | |||
204 | Type = AT->getElementType(); | |||
205 | MostDerivedLength = I + 1; | |||
206 | IsArray = true; | |||
207 | ||||
208 | if (auto *CAT = dyn_cast<ConstantArrayType>(AT)) { | |||
209 | ArraySize = CAT->getSize().getZExtValue(); | |||
210 | } else { | |||
211 | assert(I == 0 && "unexpected unsized array designator")(static_cast <bool> (I == 0 && "unexpected unsized array designator" ) ? void (0) : __assert_fail ("I == 0 && \"unexpected unsized array designator\"" , "clang/lib/AST/ExprConstant.cpp", 211, __extension__ __PRETTY_FUNCTION__ )); | |||
212 | FirstEntryIsUnsizedArray = true; | |||
213 | ArraySize = AssumedSizeForUnsizedArray; | |||
214 | } | |||
215 | } else if (Type->isAnyComplexType()) { | |||
216 | const ComplexType *CT = Type->castAs<ComplexType>(); | |||
217 | Type = CT->getElementType(); | |||
218 | ArraySize = 2; | |||
219 | MostDerivedLength = I + 1; | |||
220 | IsArray = true; | |||
221 | } else if (const FieldDecl *FD = getAsField(Path[I])) { | |||
222 | Type = FD->getType(); | |||
223 | ArraySize = 0; | |||
224 | MostDerivedLength = I + 1; | |||
225 | IsArray = false; | |||
226 | } else { | |||
227 | // Path[I] describes a base class. | |||
228 | ArraySize = 0; | |||
229 | IsArray = false; | |||
230 | } | |||
231 | } | |||
232 | return MostDerivedLength; | |||
233 | } | |||
234 | ||||
235 | /// A path from a glvalue to a subobject of that glvalue. | |||
236 | struct SubobjectDesignator { | |||
237 | /// True if the subobject was named in a manner not supported by C++11. Such | |||
238 | /// lvalues can still be folded, but they are not core constant expressions | |||
239 | /// and we cannot perform lvalue-to-rvalue conversions on them. | |||
240 | unsigned Invalid : 1; | |||
241 | ||||
242 | /// Is this a pointer one past the end of an object? | |||
243 | unsigned IsOnePastTheEnd : 1; | |||
244 | ||||
245 | /// Indicator of whether the first entry is an unsized array. | |||
246 | unsigned FirstEntryIsAnUnsizedArray : 1; | |||
247 | ||||
248 | /// Indicator of whether the most-derived object is an array element. | |||
249 | unsigned MostDerivedIsArrayElement : 1; | |||
250 | ||||
251 | /// The length of the path to the most-derived object of which this is a | |||
252 | /// subobject. | |||
253 | unsigned MostDerivedPathLength : 28; | |||
254 | ||||
255 | /// The size of the array of which the most-derived object is an element. | |||
256 | /// This will always be 0 if the most-derived object is not an array | |||
257 | /// element. 0 is not an indicator of whether or not the most-derived object | |||
258 | /// is an array, however, because 0-length arrays are allowed. | |||
259 | /// | |||
260 | /// If the current array is an unsized array, the value of this is | |||
261 | /// undefined. | |||
262 | uint64_t MostDerivedArraySize; | |||
263 | ||||
264 | /// The type of the most derived object referred to by this address. | |||
265 | QualType MostDerivedType; | |||
266 | ||||
267 | typedef APValue::LValuePathEntry PathEntry; | |||
268 | ||||
269 | /// The entries on the path from the glvalue to the designated subobject. | |||
270 | SmallVector<PathEntry, 8> Entries; | |||
271 | ||||
272 | SubobjectDesignator() : Invalid(true) {} | |||
273 | ||||
274 | explicit SubobjectDesignator(QualType T) | |||
275 | : Invalid(false), IsOnePastTheEnd(false), | |||
276 | FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false), | |||
277 | MostDerivedPathLength(0), MostDerivedArraySize(0), | |||
278 | MostDerivedType(T) {} | |||
279 | ||||
280 | SubobjectDesignator(ASTContext &Ctx, const APValue &V) | |||
281 | : Invalid(!V.isLValue() || !V.hasLValuePath()), IsOnePastTheEnd(false), | |||
282 | FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false), | |||
283 | MostDerivedPathLength(0), MostDerivedArraySize(0) { | |||
284 | assert(V.isLValue() && "Non-LValue used to make an LValue designator?")(static_cast <bool> (V.isLValue() && "Non-LValue used to make an LValue designator?" ) ? void (0) : __assert_fail ("V.isLValue() && \"Non-LValue used to make an LValue designator?\"" , "clang/lib/AST/ExprConstant.cpp", 284, __extension__ __PRETTY_FUNCTION__ )); | |||
285 | if (!Invalid) { | |||
286 | IsOnePastTheEnd = V.isLValueOnePastTheEnd(); | |||
287 | ArrayRef<PathEntry> VEntries = V.getLValuePath(); | |||
288 | Entries.insert(Entries.end(), VEntries.begin(), VEntries.end()); | |||
289 | if (V.getLValueBase()) { | |||
290 | bool IsArray = false; | |||
291 | bool FirstIsUnsizedArray = false; | |||
292 | MostDerivedPathLength = findMostDerivedSubobject( | |||
293 | Ctx, V.getLValueBase(), V.getLValuePath(), MostDerivedArraySize, | |||
294 | MostDerivedType, IsArray, FirstIsUnsizedArray); | |||
295 | MostDerivedIsArrayElement = IsArray; | |||
296 | FirstEntryIsAnUnsizedArray = FirstIsUnsizedArray; | |||
297 | } | |||
298 | } | |||
299 | } | |||
300 | ||||
301 | void truncate(ASTContext &Ctx, APValue::LValueBase Base, | |||
302 | unsigned NewLength) { | |||
303 | if (Invalid) | |||
304 | return; | |||
305 | ||||
306 | assert(Base && "cannot truncate path for null pointer")(static_cast <bool> (Base && "cannot truncate path for null pointer" ) ? void (0) : __assert_fail ("Base && \"cannot truncate path for null pointer\"" , "clang/lib/AST/ExprConstant.cpp", 306, __extension__ __PRETTY_FUNCTION__ )); | |||
307 | assert(NewLength <= Entries.size() && "not a truncation")(static_cast <bool> (NewLength <= Entries.size() && "not a truncation") ? void (0) : __assert_fail ("NewLength <= Entries.size() && \"not a truncation\"" , "clang/lib/AST/ExprConstant.cpp", 307, __extension__ __PRETTY_FUNCTION__ )); | |||
308 | ||||
309 | if (NewLength == Entries.size()) | |||
310 | return; | |||
311 | Entries.resize(NewLength); | |||
312 | ||||
313 | bool IsArray = false; | |||
314 | bool FirstIsUnsizedArray = false; | |||
315 | MostDerivedPathLength = findMostDerivedSubobject( | |||
316 | Ctx, Base, Entries, MostDerivedArraySize, MostDerivedType, IsArray, | |||
317 | FirstIsUnsizedArray); | |||
318 | MostDerivedIsArrayElement = IsArray; | |||
319 | FirstEntryIsAnUnsizedArray = FirstIsUnsizedArray; | |||
320 | } | |||
321 | ||||
322 | void setInvalid() { | |||
323 | Invalid = true; | |||
324 | Entries.clear(); | |||
325 | } | |||
326 | ||||
327 | /// Determine whether the most derived subobject is an array without a | |||
328 | /// known bound. | |||
329 | bool isMostDerivedAnUnsizedArray() const { | |||
330 | assert(!Invalid && "Calling this makes no sense on invalid designators")(static_cast <bool> (!Invalid && "Calling this makes no sense on invalid designators" ) ? void (0) : __assert_fail ("!Invalid && \"Calling this makes no sense on invalid designators\"" , "clang/lib/AST/ExprConstant.cpp", 330, __extension__ __PRETTY_FUNCTION__ )); | |||
331 | return Entries.size() == 1 && FirstEntryIsAnUnsizedArray; | |||
332 | } | |||
333 | ||||
334 | /// Determine what the most derived array's size is. Results in an assertion | |||
335 | /// failure if the most derived array lacks a size. | |||
336 | uint64_t getMostDerivedArraySize() const { | |||
337 | assert(!isMostDerivedAnUnsizedArray() && "Unsized array has no size")(static_cast <bool> (!isMostDerivedAnUnsizedArray() && "Unsized array has no size") ? void (0) : __assert_fail ("!isMostDerivedAnUnsizedArray() && \"Unsized array has no size\"" , "clang/lib/AST/ExprConstant.cpp", 337, __extension__ __PRETTY_FUNCTION__ )); | |||
338 | return MostDerivedArraySize; | |||
339 | } | |||
340 | ||||
341 | /// Determine whether this is a one-past-the-end pointer. | |||
342 | bool isOnePastTheEnd() const { | |||
343 | assert(!Invalid)(static_cast <bool> (!Invalid) ? void (0) : __assert_fail ("!Invalid", "clang/lib/AST/ExprConstant.cpp", 343, __extension__ __PRETTY_FUNCTION__)); | |||
344 | if (IsOnePastTheEnd) | |||
345 | return true; | |||
346 | if (!isMostDerivedAnUnsizedArray() && MostDerivedIsArrayElement && | |||
347 | Entries[MostDerivedPathLength - 1].getAsArrayIndex() == | |||
348 | MostDerivedArraySize) | |||
349 | return true; | |||
350 | return false; | |||
351 | } | |||
352 | ||||
353 | /// Get the range of valid index adjustments in the form | |||
354 | /// {maximum value that can be subtracted from this pointer, | |||
355 | /// maximum value that can be added to this pointer} | |||
356 | std::pair<uint64_t, uint64_t> validIndexAdjustments() { | |||
357 | if (Invalid || isMostDerivedAnUnsizedArray()) | |||
358 | return {0, 0}; | |||
359 | ||||
360 | // [expr.add]p4: For the purposes of these operators, a pointer to a | |||
361 | // nonarray object behaves the same as a pointer to the first element of | |||
362 | // an array of length one with the type of the object as its element type. | |||
363 | bool IsArray = MostDerivedPathLength == Entries.size() && | |||
364 | MostDerivedIsArrayElement; | |||
365 | uint64_t ArrayIndex = IsArray ? Entries.back().getAsArrayIndex() | |||
366 | : (uint64_t)IsOnePastTheEnd; | |||
367 | uint64_t ArraySize = | |||
368 | IsArray ? getMostDerivedArraySize() : (uint64_t)1; | |||
369 | return {ArrayIndex, ArraySize - ArrayIndex}; | |||
370 | } | |||
371 | ||||
372 | /// Check that this refers to a valid subobject. | |||
373 | bool isValidSubobject() const { | |||
374 | if (Invalid) | |||
375 | return false; | |||
376 | return !isOnePastTheEnd(); | |||
377 | } | |||
378 | /// Check that this refers to a valid subobject, and if not, produce a | |||
379 | /// relevant diagnostic and set the designator as invalid. | |||
380 | bool checkSubobject(EvalInfo &Info, const Expr *E, CheckSubobjectKind CSK); | |||
381 | ||||
382 | /// Get the type of the designated object. | |||
383 | QualType getType(ASTContext &Ctx) const { | |||
384 | assert(!Invalid && "invalid designator has no subobject type")(static_cast <bool> (!Invalid && "invalid designator has no subobject type" ) ? void (0) : __assert_fail ("!Invalid && \"invalid designator has no subobject type\"" , "clang/lib/AST/ExprConstant.cpp", 384, __extension__ __PRETTY_FUNCTION__ )); | |||
385 | return MostDerivedPathLength == Entries.size() | |||
386 | ? MostDerivedType | |||
387 | : Ctx.getRecordType(getAsBaseClass(Entries.back())); | |||
388 | } | |||
389 | ||||
390 | /// Update this designator to refer to the first element within this array. | |||
391 | void addArrayUnchecked(const ConstantArrayType *CAT) { | |||
392 | Entries.push_back(PathEntry::ArrayIndex(0)); | |||
393 | ||||
394 | // This is a most-derived object. | |||
395 | MostDerivedType = CAT->getElementType(); | |||
396 | MostDerivedIsArrayElement = true; | |||
397 | MostDerivedArraySize = CAT->getSize().getZExtValue(); | |||
398 | MostDerivedPathLength = Entries.size(); | |||
399 | } | |||
400 | /// Update this designator to refer to the first element within the array of | |||
401 | /// elements of type T. This is an array of unknown size. | |||
402 | void addUnsizedArrayUnchecked(QualType ElemTy) { | |||
403 | Entries.push_back(PathEntry::ArrayIndex(0)); | |||
404 | ||||
405 | MostDerivedType = ElemTy; | |||
406 | MostDerivedIsArrayElement = true; | |||
407 | // The value in MostDerivedArraySize is undefined in this case. So, set it | |||
408 | // to an arbitrary value that's likely to loudly break things if it's | |||
409 | // used. | |||
410 | MostDerivedArraySize = AssumedSizeForUnsizedArray; | |||
411 | MostDerivedPathLength = Entries.size(); | |||
412 | } | |||
413 | /// Update this designator to refer to the given base or member of this | |||
414 | /// object. | |||
415 | void addDeclUnchecked(const Decl *D, bool Virtual = false) { | |||
416 | Entries.push_back(APValue::BaseOrMemberType(D, Virtual)); | |||
417 | ||||
418 | // If this isn't a base class, it's a new most-derived object. | |||
419 | if (const FieldDecl *FD = dyn_cast<FieldDecl>(D)) { | |||
420 | MostDerivedType = FD->getType(); | |||
421 | MostDerivedIsArrayElement = false; | |||
422 | MostDerivedArraySize = 0; | |||
423 | MostDerivedPathLength = Entries.size(); | |||
424 | } | |||
425 | } | |||
426 | /// Update this designator to refer to the given complex component. | |||
427 | void addComplexUnchecked(QualType EltTy, bool Imag) { | |||
428 | Entries.push_back(PathEntry::ArrayIndex(Imag)); | |||
429 | ||||
430 | // This is technically a most-derived object, though in practice this | |||
431 | // is unlikely to matter. | |||
432 | MostDerivedType = EltTy; | |||
433 | MostDerivedIsArrayElement = true; | |||
434 | MostDerivedArraySize = 2; | |||
435 | MostDerivedPathLength = Entries.size(); | |||
436 | } | |||
437 | void diagnoseUnsizedArrayPointerArithmetic(EvalInfo &Info, const Expr *E); | |||
438 | void diagnosePointerArithmetic(EvalInfo &Info, const Expr *E, | |||
439 | const APSInt &N); | |||
440 | /// Add N to the address of this subobject. | |||
441 | void adjustIndex(EvalInfo &Info, const Expr *E, APSInt N) { | |||
442 | if (Invalid || !N) return; | |||
443 | uint64_t TruncatedN = N.extOrTrunc(64).getZExtValue(); | |||
444 | if (isMostDerivedAnUnsizedArray()) { | |||
445 | diagnoseUnsizedArrayPointerArithmetic(Info, E); | |||
446 | // Can't verify -- trust that the user is doing the right thing (or if | |||
447 | // not, trust that the caller will catch the bad behavior). | |||
448 | // FIXME: Should we reject if this overflows, at least? | |||
449 | Entries.back() = PathEntry::ArrayIndex( | |||
450 | Entries.back().getAsArrayIndex() + TruncatedN); | |||
451 | return; | |||
452 | } | |||
453 | ||||
454 | // [expr.add]p4: For the purposes of these operators, a pointer to a | |||
455 | // nonarray object behaves the same as a pointer to the first element of | |||
456 | // an array of length one with the type of the object as its element type. | |||
457 | bool IsArray = MostDerivedPathLength == Entries.size() && | |||
458 | MostDerivedIsArrayElement; | |||
459 | uint64_t ArrayIndex = IsArray ? Entries.back().getAsArrayIndex() | |||
460 | : (uint64_t)IsOnePastTheEnd; | |||
461 | uint64_t ArraySize = | |||
462 | IsArray ? getMostDerivedArraySize() : (uint64_t)1; | |||
463 | ||||
464 | if (N < -(int64_t)ArrayIndex || N > ArraySize - ArrayIndex) { | |||
465 | // Calculate the actual index in a wide enough type, so we can include | |||
466 | // it in the note. | |||
467 | N = N.extend(std::max<unsigned>(N.getBitWidth() + 1, 65)); | |||
468 | (llvm::APInt&)N += ArrayIndex; | |||
469 | assert(N.ugt(ArraySize) && "bounds check failed for in-bounds index")(static_cast <bool> (N.ugt(ArraySize) && "bounds check failed for in-bounds index" ) ? void (0) : __assert_fail ("N.ugt(ArraySize) && \"bounds check failed for in-bounds index\"" , "clang/lib/AST/ExprConstant.cpp", 469, __extension__ __PRETTY_FUNCTION__ )); | |||
470 | diagnosePointerArithmetic(Info, E, N); | |||
471 | setInvalid(); | |||
472 | return; | |||
473 | } | |||
474 | ||||
475 | ArrayIndex += TruncatedN; | |||
476 | assert(ArrayIndex <= ArraySize &&(static_cast <bool> (ArrayIndex <= ArraySize && "bounds check succeeded for out-of-bounds index") ? void (0) : __assert_fail ("ArrayIndex <= ArraySize && \"bounds check succeeded for out-of-bounds index\"" , "clang/lib/AST/ExprConstant.cpp", 477, __extension__ __PRETTY_FUNCTION__ )) | |||
477 | "bounds check succeeded for out-of-bounds index")(static_cast <bool> (ArrayIndex <= ArraySize && "bounds check succeeded for out-of-bounds index") ? void (0) : __assert_fail ("ArrayIndex <= ArraySize && \"bounds check succeeded for out-of-bounds index\"" , "clang/lib/AST/ExprConstant.cpp", 477, __extension__ __PRETTY_FUNCTION__ )); | |||
478 | ||||
479 | if (IsArray) | |||
480 | Entries.back() = PathEntry::ArrayIndex(ArrayIndex); | |||
481 | else | |||
482 | IsOnePastTheEnd = (ArrayIndex != 0); | |||
483 | } | |||
484 | }; | |||
485 | ||||
486 | /// A scope at the end of which an object can need to be destroyed. | |||
487 | enum class ScopeKind { | |||
488 | Block, | |||
489 | FullExpression, | |||
490 | Call | |||
491 | }; | |||
492 | ||||
493 | /// A reference to a particular call and its arguments. | |||
494 | struct CallRef { | |||
495 | CallRef() : OrigCallee(), CallIndex(0), Version() {} | |||
496 | CallRef(const FunctionDecl *Callee, unsigned CallIndex, unsigned Version) | |||
497 | : OrigCallee(Callee), CallIndex(CallIndex), Version(Version) {} | |||
498 | ||||
499 | explicit operator bool() const { return OrigCallee; } | |||
500 | ||||
501 | /// Get the parameter that the caller initialized, corresponding to the | |||
502 | /// given parameter in the callee. | |||
503 | const ParmVarDecl *getOrigParam(const ParmVarDecl *PVD) const { | |||
504 | return OrigCallee ? OrigCallee->getParamDecl(PVD->getFunctionScopeIndex()) | |||
505 | : PVD; | |||
506 | } | |||
507 | ||||
508 | /// The callee at the point where the arguments were evaluated. This might | |||
509 | /// be different from the actual callee (a different redeclaration, or a | |||
510 | /// virtual override), but this function's parameters are the ones that | |||
511 | /// appear in the parameter map. | |||
512 | const FunctionDecl *OrigCallee; | |||
513 | /// The call index of the frame that holds the argument values. | |||
514 | unsigned CallIndex; | |||
515 | /// The version of the parameters corresponding to this call. | |||
516 | unsigned Version; | |||
517 | }; | |||
518 | ||||
519 | /// A stack frame in the constexpr call stack. | |||
520 | class CallStackFrame : public interp::Frame { | |||
521 | public: | |||
522 | EvalInfo &Info; | |||
523 | ||||
524 | /// Parent - The caller of this stack frame. | |||
525 | CallStackFrame *Caller; | |||
526 | ||||
527 | /// Callee - The function which was called. | |||
528 | const FunctionDecl *Callee; | |||
529 | ||||
530 | /// This - The binding for the this pointer in this call, if any. | |||
531 | const LValue *This; | |||
532 | ||||
533 | /// Information on how to find the arguments to this call. Our arguments | |||
534 | /// are stored in our parent's CallStackFrame, using the ParmVarDecl* as a | |||
535 | /// key and this value as the version. | |||
536 | CallRef Arguments; | |||
537 | ||||
538 | /// Source location information about the default argument or default | |||
539 | /// initializer expression we're evaluating, if any. | |||
540 | CurrentSourceLocExprScope CurSourceLocExprScope; | |||
541 | ||||
542 | // Note that we intentionally use std::map here so that references to | |||
543 | // values are stable. | |||
544 | typedef std::pair<const void *, unsigned> MapKeyTy; | |||
545 | typedef std::map<MapKeyTy, APValue> MapTy; | |||
546 | /// Temporaries - Temporary lvalues materialized within this stack frame. | |||
547 | MapTy Temporaries; | |||
548 | ||||
549 | /// CallLoc - The location of the call expression for this call. | |||
550 | SourceLocation CallLoc; | |||
551 | ||||
552 | /// Index - The call index of this call. | |||
553 | unsigned Index; | |||
554 | ||||
555 | /// The stack of integers for tracking version numbers for temporaries. | |||
556 | SmallVector<unsigned, 2> TempVersionStack = {1}; | |||
557 | unsigned CurTempVersion = TempVersionStack.back(); | |||
558 | ||||
559 | unsigned getTempVersion() const { return TempVersionStack.back(); } | |||
560 | ||||
561 | void pushTempVersion() { | |||
562 | TempVersionStack.push_back(++CurTempVersion); | |||
563 | } | |||
564 | ||||
565 | void popTempVersion() { | |||
566 | TempVersionStack.pop_back(); | |||
567 | } | |||
568 | ||||
569 | CallRef createCall(const FunctionDecl *Callee) { | |||
570 | return {Callee, Index, ++CurTempVersion}; | |||
571 | } | |||
572 | ||||
573 | // FIXME: Adding this to every 'CallStackFrame' may have a nontrivial impact | |||
574 | // on the overall stack usage of deeply-recursing constexpr evaluations. | |||
575 | // (We should cache this map rather than recomputing it repeatedly.) | |||
576 | // But let's try this and see how it goes; we can look into caching the map | |||
577 | // as a later change. | |||
578 | ||||
579 | /// LambdaCaptureFields - Mapping from captured variables/this to | |||
580 | /// corresponding data members in the closure class. | |||
581 | llvm::DenseMap<const ValueDecl *, FieldDecl *> LambdaCaptureFields; | |||
582 | FieldDecl *LambdaThisCaptureField; | |||
583 | ||||
584 | CallStackFrame(EvalInfo &Info, SourceLocation CallLoc, | |||
585 | const FunctionDecl *Callee, const LValue *This, | |||
586 | CallRef Arguments); | |||
587 | ~CallStackFrame(); | |||
588 | ||||
589 | // Return the temporary for Key whose version number is Version. | |||
590 | APValue *getTemporary(const void *Key, unsigned Version) { | |||
591 | MapKeyTy KV(Key, Version); | |||
592 | auto LB = Temporaries.lower_bound(KV); | |||
593 | if (LB != Temporaries.end() && LB->first == KV) | |||
594 | return &LB->second; | |||
595 | return nullptr; | |||
596 | } | |||
597 | ||||
598 | // Return the current temporary for Key in the map. | |||
599 | APValue *getCurrentTemporary(const void *Key) { | |||
600 | auto UB = Temporaries.upper_bound(MapKeyTy(Key, UINT_MAX(2147483647 *2U +1U))); | |||
601 | if (UB != Temporaries.begin() && std::prev(UB)->first.first == Key) | |||
602 | return &std::prev(UB)->second; | |||
603 | return nullptr; | |||
604 | } | |||
605 | ||||
606 | // Return the version number of the current temporary for Key. | |||
607 | unsigned getCurrentTemporaryVersion(const void *Key) const { | |||
608 | auto UB = Temporaries.upper_bound(MapKeyTy(Key, UINT_MAX(2147483647 *2U +1U))); | |||
609 | if (UB != Temporaries.begin() && std::prev(UB)->first.first == Key) | |||
610 | return std::prev(UB)->first.second; | |||
611 | return 0; | |||
612 | } | |||
613 | ||||
614 | /// Allocate storage for an object of type T in this stack frame. | |||
615 | /// Populates LV with a handle to the created object. Key identifies | |||
616 | /// the temporary within the stack frame, and must not be reused without | |||
617 | /// bumping the temporary version number. | |||
618 | template<typename KeyT> | |||
619 | APValue &createTemporary(const KeyT *Key, QualType T, | |||
620 | ScopeKind Scope, LValue &LV); | |||
621 | ||||
622 | /// Allocate storage for a parameter of a function call made in this frame. | |||
623 | APValue &createParam(CallRef Args, const ParmVarDecl *PVD, LValue &LV); | |||
624 | ||||
625 | void describe(llvm::raw_ostream &OS) override; | |||
626 | ||||
627 | Frame *getCaller() const override { return Caller; } | |||
628 | SourceLocation getCallLocation() const override { return CallLoc; } | |||
629 | const FunctionDecl *getCallee() const override { return Callee; } | |||
630 | ||||
631 | bool isStdFunction() const { | |||
632 | for (const DeclContext *DC = Callee; DC; DC = DC->getParent()) | |||
633 | if (DC->isStdNamespace()) | |||
634 | return true; | |||
635 | return false; | |||
636 | } | |||
637 | ||||
638 | private: | |||
639 | APValue &createLocal(APValue::LValueBase Base, const void *Key, QualType T, | |||
640 | ScopeKind Scope); | |||
641 | }; | |||
642 | ||||
643 | /// Temporarily override 'this'. | |||
644 | class ThisOverrideRAII { | |||
645 | public: | |||
646 | ThisOverrideRAII(CallStackFrame &Frame, const LValue *NewThis, bool Enable) | |||
647 | : Frame(Frame), OldThis(Frame.This) { | |||
648 | if (Enable) | |||
649 | Frame.This = NewThis; | |||
650 | } | |||
651 | ~ThisOverrideRAII() { | |||
652 | Frame.This = OldThis; | |||
653 | } | |||
654 | private: | |||
655 | CallStackFrame &Frame; | |||
656 | const LValue *OldThis; | |||
657 | }; | |||
658 | ||||
659 | // A shorthand time trace scope struct, prints source range, for example | |||
660 | // {"name":"EvaluateAsRValue","args":{"detail":"<test.cc:8:21, col:25>"}}} | |||
661 | class ExprTimeTraceScope { | |||
662 | public: | |||
663 | ExprTimeTraceScope(const Expr *E, const ASTContext &Ctx, StringRef Name) | |||
664 | : TimeScope(Name, [E, &Ctx] { | |||
665 | return E->getSourceRange().printToString(Ctx.getSourceManager()); | |||
666 | }) {} | |||
667 | ||||
668 | private: | |||
669 | llvm::TimeTraceScope TimeScope; | |||
670 | }; | |||
671 | } | |||
672 | ||||
673 | static bool HandleDestruction(EvalInfo &Info, const Expr *E, | |||
674 | const LValue &This, QualType ThisType); | |||
675 | static bool HandleDestruction(EvalInfo &Info, SourceLocation Loc, | |||
676 | APValue::LValueBase LVBase, APValue &Value, | |||
677 | QualType T); | |||
678 | ||||
679 | namespace { | |||
680 | /// A cleanup, and a flag indicating whether it is lifetime-extended. | |||
681 | class Cleanup { | |||
682 | llvm::PointerIntPair<APValue*, 2, ScopeKind> Value; | |||
683 | APValue::LValueBase Base; | |||
684 | QualType T; | |||
685 | ||||
686 | public: | |||
687 | Cleanup(APValue *Val, APValue::LValueBase Base, QualType T, | |||
688 | ScopeKind Scope) | |||
689 | : Value(Val, Scope), Base(Base), T(T) {} | |||
690 | ||||
691 | /// Determine whether this cleanup should be performed at the end of the | |||
692 | /// given kind of scope. | |||
693 | bool isDestroyedAtEndOf(ScopeKind K) const { | |||
694 | return (int)Value.getInt() >= (int)K; | |||
695 | } | |||
696 | bool endLifetime(EvalInfo &Info, bool RunDestructors) { | |||
697 | if (RunDestructors) { | |||
698 | SourceLocation Loc; | |||
699 | if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>()) | |||
700 | Loc = VD->getLocation(); | |||
701 | else if (const Expr *E = Base.dyn_cast<const Expr*>()) | |||
702 | Loc = E->getExprLoc(); | |||
703 | return HandleDestruction(Info, Loc, Base, *Value.getPointer(), T); | |||
704 | } | |||
705 | *Value.getPointer() = APValue(); | |||
706 | return true; | |||
707 | } | |||
708 | ||||
709 | bool hasSideEffect() { | |||
710 | return T.isDestructedType(); | |||
711 | } | |||
712 | }; | |||
713 | ||||
714 | /// A reference to an object whose construction we are currently evaluating. | |||
715 | struct ObjectUnderConstruction { | |||
716 | APValue::LValueBase Base; | |||
717 | ArrayRef<APValue::LValuePathEntry> Path; | |||
718 | friend bool operator==(const ObjectUnderConstruction &LHS, | |||
719 | const ObjectUnderConstruction &RHS) { | |||
720 | return LHS.Base == RHS.Base && LHS.Path == RHS.Path; | |||
721 | } | |||
722 | friend llvm::hash_code hash_value(const ObjectUnderConstruction &Obj) { | |||
723 | return llvm::hash_combine(Obj.Base, Obj.Path); | |||
724 | } | |||
725 | }; | |||
726 | enum class ConstructionPhase { | |||
727 | None, | |||
728 | Bases, | |||
729 | AfterBases, | |||
730 | AfterFields, | |||
731 | Destroying, | |||
732 | DestroyingBases | |||
733 | }; | |||
734 | } | |||
735 | ||||
736 | namespace llvm { | |||
737 | template<> struct DenseMapInfo<ObjectUnderConstruction> { | |||
738 | using Base = DenseMapInfo<APValue::LValueBase>; | |||
739 | static ObjectUnderConstruction getEmptyKey() { | |||
740 | return {Base::getEmptyKey(), {}}; } | |||
741 | static ObjectUnderConstruction getTombstoneKey() { | |||
742 | return {Base::getTombstoneKey(), {}}; | |||
743 | } | |||
744 | static unsigned getHashValue(const ObjectUnderConstruction &Object) { | |||
745 | return hash_value(Object); | |||
746 | } | |||
747 | static bool isEqual(const ObjectUnderConstruction &LHS, | |||
748 | const ObjectUnderConstruction &RHS) { | |||
749 | return LHS == RHS; | |||
750 | } | |||
751 | }; | |||
752 | } | |||
753 | ||||
754 | namespace { | |||
755 | /// A dynamically-allocated heap object. | |||
756 | struct DynAlloc { | |||
757 | /// The value of this heap-allocated object. | |||
758 | APValue Value; | |||
759 | /// The allocating expression; used for diagnostics. Either a CXXNewExpr | |||
760 | /// or a CallExpr (the latter is for direct calls to operator new inside | |||
761 | /// std::allocator<T>::allocate). | |||
762 | const Expr *AllocExpr = nullptr; | |||
763 | ||||
764 | enum Kind { | |||
765 | New, | |||
766 | ArrayNew, | |||
767 | StdAllocator | |||
768 | }; | |||
769 | ||||
770 | /// Get the kind of the allocation. This must match between allocation | |||
771 | /// and deallocation. | |||
772 | Kind getKind() const { | |||
773 | if (auto *NE = dyn_cast<CXXNewExpr>(AllocExpr)) | |||
774 | return NE->isArray() ? ArrayNew : New; | |||
775 | assert(isa<CallExpr>(AllocExpr))(static_cast <bool> (isa<CallExpr>(AllocExpr)) ? void (0) : __assert_fail ("isa<CallExpr>(AllocExpr)", "clang/lib/AST/ExprConstant.cpp" , 775, __extension__ __PRETTY_FUNCTION__)); | |||
776 | return StdAllocator; | |||
777 | } | |||
778 | }; | |||
779 | ||||
780 | struct DynAllocOrder { | |||
781 | bool operator()(DynamicAllocLValue L, DynamicAllocLValue R) const { | |||
782 | return L.getIndex() < R.getIndex(); | |||
783 | } | |||
784 | }; | |||
785 | ||||
786 | /// EvalInfo - This is a private struct used by the evaluator to capture | |||
787 | /// information about a subexpression as it is folded. It retains information | |||
788 | /// about the AST context, but also maintains information about the folded | |||
789 | /// expression. | |||
790 | /// | |||
791 | /// If an expression could be evaluated, it is still possible it is not a C | |||
792 | /// "integer constant expression" or constant expression. If not, this struct | |||
793 | /// captures information about how and why not. | |||
794 | /// | |||
795 | /// One bit of information passed *into* the request for constant folding | |||
796 | /// indicates whether the subexpression is "evaluated" or not according to C | |||
797 | /// rules. For example, the RHS of (0 && foo()) is not evaluated. We can | |||
798 | /// evaluate the expression regardless of what the RHS is, but C only allows | |||
799 | /// certain things in certain situations. | |||
800 | class EvalInfo : public interp::State { | |||
801 | public: | |||
802 | ASTContext &Ctx; | |||
803 | ||||
804 | /// EvalStatus - Contains information about the evaluation. | |||
805 | Expr::EvalStatus &EvalStatus; | |||
806 | ||||
807 | /// CurrentCall - The top of the constexpr call stack. | |||
808 | CallStackFrame *CurrentCall; | |||
809 | ||||
810 | /// CallStackDepth - The number of calls in the call stack right now. | |||
811 | unsigned CallStackDepth; | |||
812 | ||||
813 | /// NextCallIndex - The next call index to assign. | |||
814 | unsigned NextCallIndex; | |||
815 | ||||
816 | /// StepsLeft - The remaining number of evaluation steps we're permitted | |||
817 | /// to perform. This is essentially a limit for the number of statements | |||
818 | /// we will evaluate. | |||
819 | unsigned StepsLeft; | |||
820 | ||||
821 | /// Enable the experimental new constant interpreter. If an expression is | |||
822 | /// not supported by the interpreter, an error is triggered. | |||
823 | bool EnableNewConstInterp; | |||
824 | ||||
825 | /// BottomFrame - The frame in which evaluation started. This must be | |||
826 | /// initialized after CurrentCall and CallStackDepth. | |||
827 | CallStackFrame BottomFrame; | |||
828 | ||||
829 | /// A stack of values whose lifetimes end at the end of some surrounding | |||
830 | /// evaluation frame. | |||
831 | llvm::SmallVector<Cleanup, 16> CleanupStack; | |||
832 | ||||
833 | /// EvaluatingDecl - This is the declaration whose initializer is being | |||
834 | /// evaluated, if any. | |||
835 | APValue::LValueBase EvaluatingDecl; | |||
836 | ||||
837 | enum class EvaluatingDeclKind { | |||
838 | None, | |||
839 | /// We're evaluating the construction of EvaluatingDecl. | |||
840 | Ctor, | |||
841 | /// We're evaluating the destruction of EvaluatingDecl. | |||
842 | Dtor, | |||
843 | }; | |||
844 | EvaluatingDeclKind IsEvaluatingDecl = EvaluatingDeclKind::None; | |||
845 | ||||
846 | /// EvaluatingDeclValue - This is the value being constructed for the | |||
847 | /// declaration whose initializer is being evaluated, if any. | |||
848 | APValue *EvaluatingDeclValue; | |||
849 | ||||
850 | /// Set of objects that are currently being constructed. | |||
851 | llvm::DenseMap<ObjectUnderConstruction, ConstructionPhase> | |||
852 | ObjectsUnderConstruction; | |||
853 | ||||
854 | /// Current heap allocations, along with the location where each was | |||
855 | /// allocated. We use std::map here because we need stable addresses | |||
856 | /// for the stored APValues. | |||
857 | std::map<DynamicAllocLValue, DynAlloc, DynAllocOrder> HeapAllocs; | |||
858 | ||||
859 | /// The number of heap allocations performed so far in this evaluation. | |||
860 | unsigned NumHeapAllocs = 0; | |||
861 | ||||
862 | struct EvaluatingConstructorRAII { | |||
863 | EvalInfo &EI; | |||
864 | ObjectUnderConstruction Object; | |||
865 | bool DidInsert; | |||
866 | EvaluatingConstructorRAII(EvalInfo &EI, ObjectUnderConstruction Object, | |||
867 | bool HasBases) | |||
868 | : EI(EI), Object(Object) { | |||
869 | DidInsert = | |||
870 | EI.ObjectsUnderConstruction | |||
871 | .insert({Object, HasBases ? ConstructionPhase::Bases | |||
872 | : ConstructionPhase::AfterBases}) | |||
873 | .second; | |||
874 | } | |||
875 | void finishedConstructingBases() { | |||
876 | EI.ObjectsUnderConstruction[Object] = ConstructionPhase::AfterBases; | |||
877 | } | |||
878 | void finishedConstructingFields() { | |||
879 | EI.ObjectsUnderConstruction[Object] = ConstructionPhase::AfterFields; | |||
880 | } | |||
881 | ~EvaluatingConstructorRAII() { | |||
882 | if (DidInsert) EI.ObjectsUnderConstruction.erase(Object); | |||
883 | } | |||
884 | }; | |||
885 | ||||
886 | struct EvaluatingDestructorRAII { | |||
887 | EvalInfo &EI; | |||
888 | ObjectUnderConstruction Object; | |||
889 | bool DidInsert; | |||
890 | EvaluatingDestructorRAII(EvalInfo &EI, ObjectUnderConstruction Object) | |||
891 | : EI(EI), Object(Object) { | |||
892 | DidInsert = EI.ObjectsUnderConstruction | |||
893 | .insert({Object, ConstructionPhase::Destroying}) | |||
894 | .second; | |||
895 | } | |||
896 | void startedDestroyingBases() { | |||
897 | EI.ObjectsUnderConstruction[Object] = | |||
898 | ConstructionPhase::DestroyingBases; | |||
899 | } | |||
900 | ~EvaluatingDestructorRAII() { | |||
901 | if (DidInsert) | |||
902 | EI.ObjectsUnderConstruction.erase(Object); | |||
903 | } | |||
904 | }; | |||
905 | ||||
906 | ConstructionPhase | |||
907 | isEvaluatingCtorDtor(APValue::LValueBase Base, | |||
908 | ArrayRef<APValue::LValuePathEntry> Path) { | |||
909 | return ObjectsUnderConstruction.lookup({Base, Path}); | |||
910 | } | |||
911 | ||||
912 | /// If we're currently speculatively evaluating, the outermost call stack | |||
913 | /// depth at which we can mutate state, otherwise 0. | |||
914 | unsigned SpeculativeEvaluationDepth = 0; | |||
915 | ||||
916 | /// The current array initialization index, if we're performing array | |||
917 | /// initialization. | |||
918 | uint64_t ArrayInitIndex = -1; | |||
919 | ||||
920 | /// HasActiveDiagnostic - Was the previous diagnostic stored? If so, further | |||
921 | /// notes attached to it will also be stored, otherwise they will not be. | |||
922 | bool HasActiveDiagnostic; | |||
923 | ||||
924 | /// Have we emitted a diagnostic explaining why we couldn't constant | |||
925 | /// fold (not just why it's not strictly a constant expression)? | |||
926 | bool HasFoldFailureDiagnostic; | |||
927 | ||||
928 | /// Whether we're checking that an expression is a potential constant | |||
929 | /// expression. If so, do not fail on constructs that could become constant | |||
930 | /// later on (such as a use of an undefined global). | |||
931 | bool CheckingPotentialConstantExpression = false; | |||
932 | ||||
933 | /// Whether we're checking for an expression that has undefined behavior. | |||
934 | /// If so, we will produce warnings if we encounter an operation that is | |||
935 | /// always undefined. | |||
936 | /// | |||
937 | /// Note that we still need to evaluate the expression normally when this | |||
938 | /// is set; this is used when evaluating ICEs in C. | |||
939 | bool CheckingForUndefinedBehavior = false; | |||
940 | ||||
941 | enum EvaluationMode { | |||
942 | /// Evaluate as a constant expression. Stop if we find that the expression | |||
943 | /// is not a constant expression. | |||
944 | EM_ConstantExpression, | |||
945 | ||||
946 | /// Evaluate as a constant expression. Stop if we find that the expression | |||
947 | /// is not a constant expression. Some expressions can be retried in the | |||
948 | /// optimizer if we don't constant fold them here, but in an unevaluated | |||
949 | /// context we try to fold them immediately since the optimizer never | |||
950 | /// gets a chance to look at it. | |||
951 | EM_ConstantExpressionUnevaluated, | |||
952 | ||||
953 | /// Fold the expression to a constant. Stop if we hit a side-effect that | |||
954 | /// we can't model. | |||
955 | EM_ConstantFold, | |||
956 | ||||
957 | /// Evaluate in any way we know how. Don't worry about side-effects that | |||
958 | /// can't be modeled. | |||
959 | EM_IgnoreSideEffects, | |||
960 | } EvalMode; | |||
961 | ||||
962 | /// Are we checking whether the expression is a potential constant | |||
963 | /// expression? | |||
964 | bool checkingPotentialConstantExpression() const override { | |||
965 | return CheckingPotentialConstantExpression; | |||
966 | } | |||
967 | ||||
968 | /// Are we checking an expression for overflow? | |||
969 | // FIXME: We should check for any kind of undefined or suspicious behavior | |||
970 | // in such constructs, not just overflow. | |||
971 | bool checkingForUndefinedBehavior() const override { | |||
972 | return CheckingForUndefinedBehavior; | |||
973 | } | |||
974 | ||||
975 | EvalInfo(const ASTContext &C, Expr::EvalStatus &S, EvaluationMode Mode) | |||
976 | : Ctx(const_cast<ASTContext &>(C)), EvalStatus(S), CurrentCall(nullptr), | |||
977 | CallStackDepth(0), NextCallIndex(1), | |||
978 | StepsLeft(C.getLangOpts().ConstexprStepLimit), | |||
979 | EnableNewConstInterp(C.getLangOpts().EnableNewConstInterp), | |||
980 | BottomFrame(*this, SourceLocation(), nullptr, nullptr, CallRef()), | |||
981 | EvaluatingDecl((const ValueDecl *)nullptr), | |||
982 | EvaluatingDeclValue(nullptr), HasActiveDiagnostic(false), | |||
983 | HasFoldFailureDiagnostic(false), EvalMode(Mode) {} | |||
984 | ||||
985 | ~EvalInfo() { | |||
986 | discardCleanups(); | |||
987 | } | |||
988 | ||||
989 | ASTContext &getCtx() const override { return Ctx; } | |||
990 | ||||
991 | void setEvaluatingDecl(APValue::LValueBase Base, APValue &Value, | |||
992 | EvaluatingDeclKind EDK = EvaluatingDeclKind::Ctor) { | |||
993 | EvaluatingDecl = Base; | |||
994 | IsEvaluatingDecl = EDK; | |||
995 | EvaluatingDeclValue = &Value; | |||
996 | } | |||
997 | ||||
998 | bool CheckCallLimit(SourceLocation Loc) { | |||
999 | // Don't perform any constexpr calls (other than the call we're checking) | |||
1000 | // when checking a potential constant expression. | |||
1001 | if (checkingPotentialConstantExpression() && CallStackDepth > 1) | |||
1002 | return false; | |||
1003 | if (NextCallIndex == 0) { | |||
1004 | // NextCallIndex has wrapped around. | |||
1005 | FFDiag(Loc, diag::note_constexpr_call_limit_exceeded); | |||
1006 | return false; | |||
1007 | } | |||
1008 | if (CallStackDepth <= getLangOpts().ConstexprCallDepth) | |||
1009 | return true; | |||
1010 | FFDiag(Loc, diag::note_constexpr_depth_limit_exceeded) | |||
1011 | << getLangOpts().ConstexprCallDepth; | |||
1012 | return false; | |||
1013 | } | |||
1014 | ||||
1015 | std::pair<CallStackFrame *, unsigned> | |||
1016 | getCallFrameAndDepth(unsigned CallIndex) { | |||
1017 | assert(CallIndex && "no call index in getCallFrameAndDepth")(static_cast <bool> (CallIndex && "no call index in getCallFrameAndDepth" ) ? void (0) : __assert_fail ("CallIndex && \"no call index in getCallFrameAndDepth\"" , "clang/lib/AST/ExprConstant.cpp", 1017, __extension__ __PRETTY_FUNCTION__ )); | |||
1018 | // We will eventually hit BottomFrame, which has Index 1, so Frame can't | |||
1019 | // be null in this loop. | |||
1020 | unsigned Depth = CallStackDepth; | |||
1021 | CallStackFrame *Frame = CurrentCall; | |||
1022 | while (Frame->Index > CallIndex) { | |||
1023 | Frame = Frame->Caller; | |||
1024 | --Depth; | |||
1025 | } | |||
1026 | if (Frame->Index == CallIndex) | |||
1027 | return {Frame, Depth}; | |||
1028 | return {nullptr, 0}; | |||
1029 | } | |||
1030 | ||||
1031 | bool nextStep(const Stmt *S) { | |||
1032 | if (!StepsLeft) { | |||
1033 | FFDiag(S->getBeginLoc(), diag::note_constexpr_step_limit_exceeded); | |||
1034 | return false; | |||
1035 | } | |||
1036 | --StepsLeft; | |||
1037 | return true; | |||
1038 | } | |||
1039 | ||||
1040 | APValue *createHeapAlloc(const Expr *E, QualType T, LValue &LV); | |||
1041 | ||||
1042 | std::optional<DynAlloc *> lookupDynamicAlloc(DynamicAllocLValue DA) { | |||
1043 | std::optional<DynAlloc *> Result; | |||
1044 | auto It = HeapAllocs.find(DA); | |||
1045 | if (It != HeapAllocs.end()) | |||
1046 | Result = &It->second; | |||
1047 | return Result; | |||
1048 | } | |||
1049 | ||||
1050 | /// Get the allocated storage for the given parameter of the given call. | |||
1051 | APValue *getParamSlot(CallRef Call, const ParmVarDecl *PVD) { | |||
1052 | CallStackFrame *Frame = getCallFrameAndDepth(Call.CallIndex).first; | |||
1053 | return Frame ? Frame->getTemporary(Call.getOrigParam(PVD), Call.Version) | |||
1054 | : nullptr; | |||
1055 | } | |||
1056 | ||||
1057 | /// Information about a stack frame for std::allocator<T>::[de]allocate. | |||
1058 | struct StdAllocatorCaller { | |||
1059 | unsigned FrameIndex; | |||
1060 | QualType ElemType; | |||
1061 | explicit operator bool() const { return FrameIndex != 0; }; | |||
1062 | }; | |||
1063 | ||||
1064 | StdAllocatorCaller getStdAllocatorCaller(StringRef FnName) const { | |||
1065 | for (const CallStackFrame *Call = CurrentCall; Call != &BottomFrame; | |||
1066 | Call = Call->Caller) { | |||
1067 | const auto *MD = dyn_cast_or_null<CXXMethodDecl>(Call->Callee); | |||
1068 | if (!MD) | |||
1069 | continue; | |||
1070 | const IdentifierInfo *FnII = MD->getIdentifier(); | |||
1071 | if (!FnII || !FnII->isStr(FnName)) | |||
1072 | continue; | |||
1073 | ||||
1074 | const auto *CTSD = | |||
1075 | dyn_cast<ClassTemplateSpecializationDecl>(MD->getParent()); | |||
1076 | if (!CTSD) | |||
1077 | continue; | |||
1078 | ||||
1079 | const IdentifierInfo *ClassII = CTSD->getIdentifier(); | |||
1080 | const TemplateArgumentList &TAL = CTSD->getTemplateArgs(); | |||
1081 | if (CTSD->isInStdNamespace() && ClassII && | |||
1082 | ClassII->isStr("allocator") && TAL.size() >= 1 && | |||
1083 | TAL[0].getKind() == TemplateArgument::Type) | |||
1084 | return {Call->Index, TAL[0].getAsType()}; | |||
1085 | } | |||
1086 | ||||
1087 | return {}; | |||
1088 | } | |||
1089 | ||||
1090 | void performLifetimeExtension() { | |||
1091 | // Disable the cleanups for lifetime-extended temporaries. | |||
1092 | llvm::erase_if(CleanupStack, [](Cleanup &C) { | |||
1093 | return !C.isDestroyedAtEndOf(ScopeKind::FullExpression); | |||
1094 | }); | |||
1095 | } | |||
1096 | ||||
1097 | /// Throw away any remaining cleanups at the end of evaluation. If any | |||
1098 | /// cleanups would have had a side-effect, note that as an unmodeled | |||
1099 | /// side-effect and return false. Otherwise, return true. | |||
1100 | bool discardCleanups() { | |||
1101 | for (Cleanup &C : CleanupStack) { | |||
1102 | if (C.hasSideEffect() && !noteSideEffect()) { | |||
1103 | CleanupStack.clear(); | |||
1104 | return false; | |||
1105 | } | |||
1106 | } | |||
1107 | CleanupStack.clear(); | |||
1108 | return true; | |||
1109 | } | |||
1110 | ||||
1111 | private: | |||
1112 | interp::Frame *getCurrentFrame() override { return CurrentCall; } | |||
1113 | const interp::Frame *getBottomFrame() const override { return &BottomFrame; } | |||
1114 | ||||
1115 | bool hasActiveDiagnostic() override { return HasActiveDiagnostic; } | |||
1116 | void setActiveDiagnostic(bool Flag) override { HasActiveDiagnostic = Flag; } | |||
1117 | ||||
1118 | void setFoldFailureDiagnostic(bool Flag) override { | |||
1119 | HasFoldFailureDiagnostic = Flag; | |||
1120 | } | |||
1121 | ||||
1122 | Expr::EvalStatus &getEvalStatus() const override { return EvalStatus; } | |||
1123 | ||||
1124 | // If we have a prior diagnostic, it will be noting that the expression | |||
1125 | // isn't a constant expression. This diagnostic is more important, | |||
1126 | // unless we require this evaluation to produce a constant expression. | |||
1127 | // | |||
1128 | // FIXME: We might want to show both diagnostics to the user in | |||
1129 | // EM_ConstantFold mode. | |||
1130 | bool hasPriorDiagnostic() override { | |||
1131 | if (!EvalStatus.Diag->empty()) { | |||
1132 | switch (EvalMode) { | |||
1133 | case EM_ConstantFold: | |||
1134 | case EM_IgnoreSideEffects: | |||
1135 | if (!HasFoldFailureDiagnostic) | |||
1136 | break; | |||
1137 | // We've already failed to fold something. Keep that diagnostic. | |||
1138 | [[fallthrough]]; | |||
1139 | case EM_ConstantExpression: | |||
1140 | case EM_ConstantExpressionUnevaluated: | |||
1141 | setActiveDiagnostic(false); | |||
1142 | return true; | |||
1143 | } | |||
1144 | } | |||
1145 | return false; | |||
1146 | } | |||
1147 | ||||
1148 | unsigned getCallStackDepth() override { return CallStackDepth; } | |||
1149 | ||||
1150 | public: | |||
1151 | /// Should we continue evaluation after encountering a side-effect that we | |||
1152 | /// couldn't model? | |||
1153 | bool keepEvaluatingAfterSideEffect() { | |||
1154 | switch (EvalMode) { | |||
1155 | case EM_IgnoreSideEffects: | |||
1156 | return true; | |||
1157 | ||||
1158 | case EM_ConstantExpression: | |||
1159 | case EM_ConstantExpressionUnevaluated: | |||
1160 | case EM_ConstantFold: | |||
1161 | // By default, assume any side effect might be valid in some other | |||
1162 | // evaluation of this expression from a different context. | |||
1163 | return checkingPotentialConstantExpression() || | |||
1164 | checkingForUndefinedBehavior(); | |||
1165 | } | |||
1166 | llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "clang/lib/AST/ExprConstant.cpp" , 1166); | |||
1167 | } | |||
1168 | ||||
1169 | /// Note that we have had a side-effect, and determine whether we should | |||
1170 | /// keep evaluating. | |||
1171 | bool noteSideEffect() { | |||
1172 | EvalStatus.HasSideEffects = true; | |||
1173 | return keepEvaluatingAfterSideEffect(); | |||
1174 | } | |||
1175 | ||||
1176 | /// Should we continue evaluation after encountering undefined behavior? | |||
1177 | bool keepEvaluatingAfterUndefinedBehavior() { | |||
1178 | switch (EvalMode) { | |||
1179 | case EM_IgnoreSideEffects: | |||
1180 | case EM_ConstantFold: | |||
1181 | return true; | |||
1182 | ||||
1183 | case EM_ConstantExpression: | |||
1184 | case EM_ConstantExpressionUnevaluated: | |||
1185 | return checkingForUndefinedBehavior(); | |||
1186 | } | |||
1187 | llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "clang/lib/AST/ExprConstant.cpp" , 1187); | |||
1188 | } | |||
1189 | ||||
1190 | /// Note that we hit something that was technically undefined behavior, but | |||
1191 | /// that we can evaluate past it (such as signed overflow or floating-point | |||
1192 | /// division by zero.) | |||
1193 | bool noteUndefinedBehavior() override { | |||
1194 | EvalStatus.HasUndefinedBehavior = true; | |||
1195 | return keepEvaluatingAfterUndefinedBehavior(); | |||
1196 | } | |||
1197 | ||||
1198 | /// Should we continue evaluation as much as possible after encountering a | |||
1199 | /// construct which can't be reduced to a value? | |||
1200 | bool keepEvaluatingAfterFailure() const override { | |||
1201 | if (!StepsLeft) | |||
1202 | return false; | |||
1203 | ||||
1204 | switch (EvalMode) { | |||
1205 | case EM_ConstantExpression: | |||
1206 | case EM_ConstantExpressionUnevaluated: | |||
1207 | case EM_ConstantFold: | |||
1208 | case EM_IgnoreSideEffects: | |||
1209 | return checkingPotentialConstantExpression() || | |||
1210 | checkingForUndefinedBehavior(); | |||
1211 | } | |||
1212 | llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "clang/lib/AST/ExprConstant.cpp" , 1212); | |||
1213 | } | |||
1214 | ||||
1215 | /// Notes that we failed to evaluate an expression that other expressions | |||
1216 | /// directly depend on, and determine if we should keep evaluating. This | |||
1217 | /// should only be called if we actually intend to keep evaluating. | |||
1218 | /// | |||
1219 | /// Call noteSideEffect() instead if we may be able to ignore the value that | |||
1220 | /// we failed to evaluate, e.g. if we failed to evaluate Foo() in: | |||
1221 | /// | |||
1222 | /// (Foo(), 1) // use noteSideEffect | |||
1223 | /// (Foo() || true) // use noteSideEffect | |||
1224 | /// Foo() + 1 // use noteFailure | |||
1225 | [[nodiscard]] bool noteFailure() { | |||
1226 | // Failure when evaluating some expression often means there is some | |||
1227 | // subexpression whose evaluation was skipped. Therefore, (because we | |||
1228 | // don't track whether we skipped an expression when unwinding after an | |||
1229 | // evaluation failure) every evaluation failure that bubbles up from a | |||
1230 | // subexpression implies that a side-effect has potentially happened. We | |||
1231 | // skip setting the HasSideEffects flag to true until we decide to | |||
1232 | // continue evaluating after that point, which happens here. | |||
1233 | bool KeepGoing = keepEvaluatingAfterFailure(); | |||
1234 | EvalStatus.HasSideEffects |= KeepGoing; | |||
1235 | return KeepGoing; | |||
1236 | } | |||
1237 | ||||
1238 | class ArrayInitLoopIndex { | |||
1239 | EvalInfo &Info; | |||
1240 | uint64_t OuterIndex; | |||
1241 | ||||
1242 | public: | |||
1243 | ArrayInitLoopIndex(EvalInfo &Info) | |||
1244 | : Info(Info), OuterIndex(Info.ArrayInitIndex) { | |||
1245 | Info.ArrayInitIndex = 0; | |||
1246 | } | |||
1247 | ~ArrayInitLoopIndex() { Info.ArrayInitIndex = OuterIndex; } | |||
1248 | ||||
1249 | operator uint64_t&() { return Info.ArrayInitIndex; } | |||
1250 | }; | |||
1251 | }; | |||
1252 | ||||
1253 | /// Object used to treat all foldable expressions as constant expressions. | |||
1254 | struct FoldConstant { | |||
1255 | EvalInfo &Info; | |||
1256 | bool Enabled; | |||
1257 | bool HadNoPriorDiags; | |||
1258 | EvalInfo::EvaluationMode OldMode; | |||
1259 | ||||
1260 | explicit FoldConstant(EvalInfo &Info, bool Enabled) | |||
1261 | : Info(Info), | |||
1262 | Enabled(Enabled), | |||
1263 | HadNoPriorDiags(Info.EvalStatus.Diag && | |||
1264 | Info.EvalStatus.Diag->empty() && | |||
1265 | !Info.EvalStatus.HasSideEffects), | |||
1266 | OldMode(Info.EvalMode) { | |||
1267 | if (Enabled) | |||
1268 | Info.EvalMode = EvalInfo::EM_ConstantFold; | |||
1269 | } | |||
1270 | void keepDiagnostics() { Enabled = false; } | |||
1271 | ~FoldConstant() { | |||
1272 | if (Enabled && HadNoPriorDiags && !Info.EvalStatus.Diag->empty() && | |||
1273 | !Info.EvalStatus.HasSideEffects) | |||
1274 | Info.EvalStatus.Diag->clear(); | |||
1275 | Info.EvalMode = OldMode; | |||
1276 | } | |||
1277 | }; | |||
1278 | ||||
1279 | /// RAII object used to set the current evaluation mode to ignore | |||
1280 | /// side-effects. | |||
1281 | struct IgnoreSideEffectsRAII { | |||
1282 | EvalInfo &Info; | |||
1283 | EvalInfo::EvaluationMode OldMode; | |||
1284 | explicit IgnoreSideEffectsRAII(EvalInfo &Info) | |||
1285 | : Info(Info), OldMode(Info.EvalMode) { | |||
1286 | Info.EvalMode = EvalInfo::EM_IgnoreSideEffects; | |||
1287 | } | |||
1288 | ||||
1289 | ~IgnoreSideEffectsRAII() { Info.EvalMode = OldMode; } | |||
1290 | }; | |||
1291 | ||||
1292 | /// RAII object used to optionally suppress diagnostics and side-effects from | |||
1293 | /// a speculative evaluation. | |||
1294 | class SpeculativeEvaluationRAII { | |||
1295 | EvalInfo *Info = nullptr; | |||
1296 | Expr::EvalStatus OldStatus; | |||
1297 | unsigned OldSpeculativeEvaluationDepth; | |||
1298 | ||||
1299 | void moveFromAndCancel(SpeculativeEvaluationRAII &&Other) { | |||
1300 | Info = Other.Info; | |||
1301 | OldStatus = Other.OldStatus; | |||
1302 | OldSpeculativeEvaluationDepth = Other.OldSpeculativeEvaluationDepth; | |||
1303 | Other.Info = nullptr; | |||
1304 | } | |||
1305 | ||||
1306 | void maybeRestoreState() { | |||
1307 | if (!Info) | |||
1308 | return; | |||
1309 | ||||
1310 | Info->EvalStatus = OldStatus; | |||
1311 | Info->SpeculativeEvaluationDepth = OldSpeculativeEvaluationDepth; | |||
1312 | } | |||
1313 | ||||
1314 | public: | |||
1315 | SpeculativeEvaluationRAII() = default; | |||
1316 | ||||
1317 | SpeculativeEvaluationRAII( | |||
1318 | EvalInfo &Info, SmallVectorImpl<PartialDiagnosticAt> *NewDiag = nullptr) | |||
1319 | : Info(&Info), OldStatus(Info.EvalStatus), | |||
1320 | OldSpeculativeEvaluationDepth(Info.SpeculativeEvaluationDepth) { | |||
1321 | Info.EvalStatus.Diag = NewDiag; | |||
1322 | Info.SpeculativeEvaluationDepth = Info.CallStackDepth + 1; | |||
1323 | } | |||
1324 | ||||
1325 | SpeculativeEvaluationRAII(const SpeculativeEvaluationRAII &Other) = delete; | |||
1326 | SpeculativeEvaluationRAII(SpeculativeEvaluationRAII &&Other) { | |||
1327 | moveFromAndCancel(std::move(Other)); | |||
1328 | } | |||
1329 | ||||
1330 | SpeculativeEvaluationRAII &operator=(SpeculativeEvaluationRAII &&Other) { | |||
1331 | maybeRestoreState(); | |||
1332 | moveFromAndCancel(std::move(Other)); | |||
1333 | return *this; | |||
1334 | } | |||
1335 | ||||
1336 | ~SpeculativeEvaluationRAII() { maybeRestoreState(); } | |||
1337 | }; | |||
1338 | ||||
1339 | /// RAII object wrapping a full-expression or block scope, and handling | |||
1340 | /// the ending of the lifetime of temporaries created within it. | |||
1341 | template<ScopeKind Kind> | |||
1342 | class ScopeRAII { | |||
1343 | EvalInfo &Info; | |||
1344 | unsigned OldStackSize; | |||
1345 | public: | |||
1346 | ScopeRAII(EvalInfo &Info) | |||
1347 | : Info(Info), OldStackSize(Info.CleanupStack.size()) { | |||
1348 | // Push a new temporary version. This is needed to distinguish between | |||
1349 | // temporaries created in different iterations of a loop. | |||
1350 | Info.CurrentCall->pushTempVersion(); | |||
1351 | } | |||
1352 | bool destroy(bool RunDestructors = true) { | |||
1353 | bool OK = cleanup(Info, RunDestructors, OldStackSize); | |||
1354 | OldStackSize = -1U; | |||
1355 | return OK; | |||
1356 | } | |||
1357 | ~ScopeRAII() { | |||
1358 | if (OldStackSize != -1U) | |||
1359 | destroy(false); | |||
1360 | // Body moved to a static method to encourage the compiler to inline away | |||
1361 | // instances of this class. | |||
1362 | Info.CurrentCall->popTempVersion(); | |||
1363 | } | |||
1364 | private: | |||
1365 | static bool cleanup(EvalInfo &Info, bool RunDestructors, | |||
1366 | unsigned OldStackSize) { | |||
1367 | assert(OldStackSize <= Info.CleanupStack.size() &&(static_cast <bool> (OldStackSize <= Info.CleanupStack .size() && "running cleanups out of order?") ? void ( 0) : __assert_fail ("OldStackSize <= Info.CleanupStack.size() && \"running cleanups out of order?\"" , "clang/lib/AST/ExprConstant.cpp", 1368, __extension__ __PRETTY_FUNCTION__ )) | |||
1368 | "running cleanups out of order?")(static_cast <bool> (OldStackSize <= Info.CleanupStack .size() && "running cleanups out of order?") ? void ( 0) : __assert_fail ("OldStackSize <= Info.CleanupStack.size() && \"running cleanups out of order?\"" , "clang/lib/AST/ExprConstant.cpp", 1368, __extension__ __PRETTY_FUNCTION__ )); | |||
1369 | ||||
1370 | // Run all cleanups for a block scope, and non-lifetime-extended cleanups | |||
1371 | // for a full-expression scope. | |||
1372 | bool Success = true; | |||
1373 | for (unsigned I = Info.CleanupStack.size(); I > OldStackSize; --I) { | |||
1374 | if (Info.CleanupStack[I - 1].isDestroyedAtEndOf(Kind)) { | |||
1375 | if (!Info.CleanupStack[I - 1].endLifetime(Info, RunDestructors)) { | |||
1376 | Success = false; | |||
1377 | break; | |||
1378 | } | |||
1379 | } | |||
1380 | } | |||
1381 | ||||
1382 | // Compact any retained cleanups. | |||
1383 | auto NewEnd = Info.CleanupStack.begin() + OldStackSize; | |||
1384 | if (Kind != ScopeKind::Block) | |||
1385 | NewEnd = | |||
1386 | std::remove_if(NewEnd, Info.CleanupStack.end(), [](Cleanup &C) { | |||
1387 | return C.isDestroyedAtEndOf(Kind); | |||
1388 | }); | |||
1389 | Info.CleanupStack.erase(NewEnd, Info.CleanupStack.end()); | |||
1390 | return Success; | |||
1391 | } | |||
1392 | }; | |||
1393 | typedef ScopeRAII<ScopeKind::Block> BlockScopeRAII; | |||
1394 | typedef ScopeRAII<ScopeKind::FullExpression> FullExpressionRAII; | |||
1395 | typedef ScopeRAII<ScopeKind::Call> CallScopeRAII; | |||
1396 | } | |||
1397 | ||||
1398 | bool SubobjectDesignator::checkSubobject(EvalInfo &Info, const Expr *E, | |||
1399 | CheckSubobjectKind CSK) { | |||
1400 | if (Invalid) | |||
1401 | return false; | |||
1402 | if (isOnePastTheEnd()) { | |||
1403 | Info.CCEDiag(E, diag::note_constexpr_past_end_subobject) | |||
1404 | << CSK; | |||
1405 | setInvalid(); | |||
1406 | return false; | |||
1407 | } | |||
1408 | // Note, we do not diagnose if isMostDerivedAnUnsizedArray(), because there | |||
1409 | // must actually be at least one array element; even a VLA cannot have a | |||
1410 | // bound of zero. And if our index is nonzero, we already had a CCEDiag. | |||
1411 | return true; | |||
1412 | } | |||
1413 | ||||
1414 | void SubobjectDesignator::diagnoseUnsizedArrayPointerArithmetic(EvalInfo &Info, | |||
1415 | const Expr *E) { | |||
1416 | Info.CCEDiag(E, diag::note_constexpr_unsized_array_indexed); | |||
1417 | // Do not set the designator as invalid: we can represent this situation, | |||
1418 | // and correct handling of __builtin_object_size requires us to do so. | |||
1419 | } | |||
1420 | ||||
1421 | void SubobjectDesignator::diagnosePointerArithmetic(EvalInfo &Info, | |||
1422 | const Expr *E, | |||
1423 | const APSInt &N) { | |||
1424 | // If we're complaining, we must be able to statically determine the size of | |||
1425 | // the most derived array. | |||
1426 | if (MostDerivedPathLength == Entries.size() && MostDerivedIsArrayElement) | |||
1427 | Info.CCEDiag(E, diag::note_constexpr_array_index) | |||
1428 | << N << /*array*/ 0 | |||
1429 | << static_cast<unsigned>(getMostDerivedArraySize()); | |||
1430 | else | |||
1431 | Info.CCEDiag(E, diag::note_constexpr_array_index) | |||
1432 | << N << /*non-array*/ 1; | |||
1433 | setInvalid(); | |||
1434 | } | |||
1435 | ||||
1436 | CallStackFrame::CallStackFrame(EvalInfo &Info, SourceLocation CallLoc, | |||
1437 | const FunctionDecl *Callee, const LValue *This, | |||
1438 | CallRef Call) | |||
1439 | : Info(Info), Caller(Info.CurrentCall), Callee(Callee), This(This), | |||
1440 | Arguments(Call), CallLoc(CallLoc), Index(Info.NextCallIndex++) { | |||
1441 | Info.CurrentCall = this; | |||
1442 | ++Info.CallStackDepth; | |||
1443 | } | |||
1444 | ||||
1445 | CallStackFrame::~CallStackFrame() { | |||
1446 | assert(Info.CurrentCall == this && "calls retired out of order")(static_cast <bool> (Info.CurrentCall == this && "calls retired out of order") ? void (0) : __assert_fail ("Info.CurrentCall == this && \"calls retired out of order\"" , "clang/lib/AST/ExprConstant.cpp", 1446, __extension__ __PRETTY_FUNCTION__ )); | |||
1447 | --Info.CallStackDepth; | |||
1448 | Info.CurrentCall = Caller; | |||
1449 | } | |||
1450 | ||||
1451 | static bool isRead(AccessKinds AK) { | |||
1452 | return AK == AK_Read || AK == AK_ReadObjectRepresentation; | |||
1453 | } | |||
1454 | ||||
1455 | static bool isModification(AccessKinds AK) { | |||
1456 | switch (AK) { | |||
1457 | case AK_Read: | |||
1458 | case AK_ReadObjectRepresentation: | |||
1459 | case AK_MemberCall: | |||
1460 | case AK_DynamicCast: | |||
1461 | case AK_TypeId: | |||
1462 | return false; | |||
1463 | case AK_Assign: | |||
1464 | case AK_Increment: | |||
1465 | case AK_Decrement: | |||
1466 | case AK_Construct: | |||
1467 | case AK_Destroy: | |||
1468 | return true; | |||
1469 | } | |||
1470 | llvm_unreachable("unknown access kind")::llvm::llvm_unreachable_internal("unknown access kind", "clang/lib/AST/ExprConstant.cpp" , 1470); | |||
1471 | } | |||
1472 | ||||
1473 | static bool isAnyAccess(AccessKinds AK) { | |||
1474 | return isRead(AK) || isModification(AK); | |||
1475 | } | |||
1476 | ||||
1477 | /// Is this an access per the C++ definition? | |||
1478 | static bool isFormalAccess(AccessKinds AK) { | |||
1479 | return isAnyAccess(AK) && AK != AK_Construct && AK != AK_Destroy; | |||
1480 | } | |||
1481 | ||||
1482 | /// Is this kind of axcess valid on an indeterminate object value? | |||
1483 | static bool isValidIndeterminateAccess(AccessKinds AK) { | |||
1484 | switch (AK) { | |||
1485 | case AK_Read: | |||
1486 | case AK_Increment: | |||
1487 | case AK_Decrement: | |||
1488 | // These need the object's value. | |||
1489 | return false; | |||
1490 | ||||
1491 | case AK_ReadObjectRepresentation: | |||
1492 | case AK_Assign: | |||
1493 | case AK_Construct: | |||
1494 | case AK_Destroy: | |||
1495 | // Construction and destruction don't need the value. | |||
1496 | return true; | |||
1497 | ||||
1498 | case AK_MemberCall: | |||
1499 | case AK_DynamicCast: | |||
1500 | case AK_TypeId: | |||
1501 | // These aren't really meaningful on scalars. | |||
1502 | return true; | |||
1503 | } | |||
1504 | llvm_unreachable("unknown access kind")::llvm::llvm_unreachable_internal("unknown access kind", "clang/lib/AST/ExprConstant.cpp" , 1504); | |||
1505 | } | |||
1506 | ||||
1507 | namespace { | |||
1508 | struct ComplexValue { | |||
1509 | private: | |||
1510 | bool IsInt; | |||
1511 | ||||
1512 | public: | |||
1513 | APSInt IntReal, IntImag; | |||
1514 | APFloat FloatReal, FloatImag; | |||
1515 | ||||
1516 | ComplexValue() : FloatReal(APFloat::Bogus()), FloatImag(APFloat::Bogus()) {} | |||
1517 | ||||
1518 | void makeComplexFloat() { IsInt = false; } | |||
1519 | bool isComplexFloat() const { return !IsInt; } | |||
1520 | APFloat &getComplexFloatReal() { return FloatReal; } | |||
1521 | APFloat &getComplexFloatImag() { return FloatImag; } | |||
1522 | ||||
1523 | void makeComplexInt() { IsInt = true; } | |||
1524 | bool isComplexInt() const { return IsInt; } | |||
1525 | APSInt &getComplexIntReal() { return IntReal; } | |||
1526 | APSInt &getComplexIntImag() { return IntImag; } | |||
1527 | ||||
1528 | void moveInto(APValue &v) const { | |||
1529 | if (isComplexFloat()) | |||
1530 | v = APValue(FloatReal, FloatImag); | |||
1531 | else | |||
1532 | v = APValue(IntReal, IntImag); | |||
1533 | } | |||
1534 | void setFrom(const APValue &v) { | |||
1535 | assert(v.isComplexFloat() || v.isComplexInt())(static_cast <bool> (v.isComplexFloat() || v.isComplexInt ()) ? void (0) : __assert_fail ("v.isComplexFloat() || v.isComplexInt()" , "clang/lib/AST/ExprConstant.cpp", 1535, __extension__ __PRETTY_FUNCTION__ )); | |||
1536 | if (v.isComplexFloat()) { | |||
1537 | makeComplexFloat(); | |||
1538 | FloatReal = v.getComplexFloatReal(); | |||
1539 | FloatImag = v.getComplexFloatImag(); | |||
1540 | } else { | |||
1541 | makeComplexInt(); | |||
1542 | IntReal = v.getComplexIntReal(); | |||
1543 | IntImag = v.getComplexIntImag(); | |||
1544 | } | |||
1545 | } | |||
1546 | }; | |||
1547 | ||||
1548 | struct LValue { | |||
1549 | APValue::LValueBase Base; | |||
1550 | CharUnits Offset; | |||
1551 | SubobjectDesignator Designator; | |||
1552 | bool IsNullPtr : 1; | |||
1553 | bool InvalidBase : 1; | |||
1554 | ||||
1555 | const APValue::LValueBase getLValueBase() const { return Base; } | |||
1556 | CharUnits &getLValueOffset() { return Offset; } | |||
1557 | const CharUnits &getLValueOffset() const { return Offset; } | |||
1558 | SubobjectDesignator &getLValueDesignator() { return Designator; } | |||
1559 | const SubobjectDesignator &getLValueDesignator() const { return Designator;} | |||
1560 | bool isNullPointer() const { return IsNullPtr;} | |||
1561 | ||||
1562 | unsigned getLValueCallIndex() const { return Base.getCallIndex(); } | |||
1563 | unsigned getLValueVersion() const { return Base.getVersion(); } | |||
1564 | ||||
1565 | void moveInto(APValue &V) const { | |||
1566 | if (Designator.Invalid) | |||
1567 | V = APValue(Base, Offset, APValue::NoLValuePath(), IsNullPtr); | |||
1568 | else { | |||
1569 | assert(!InvalidBase && "APValues can't handle invalid LValue bases")(static_cast <bool> (!InvalidBase && "APValues can't handle invalid LValue bases" ) ? void (0) : __assert_fail ("!InvalidBase && \"APValues can't handle invalid LValue bases\"" , "clang/lib/AST/ExprConstant.cpp", 1569, __extension__ __PRETTY_FUNCTION__ )); | |||
1570 | V = APValue(Base, Offset, Designator.Entries, | |||
1571 | Designator.IsOnePastTheEnd, IsNullPtr); | |||
1572 | } | |||
1573 | } | |||
1574 | void setFrom(ASTContext &Ctx, const APValue &V) { | |||
1575 | assert(V.isLValue() && "Setting LValue from a non-LValue?")(static_cast <bool> (V.isLValue() && "Setting LValue from a non-LValue?" ) ? void (0) : __assert_fail ("V.isLValue() && \"Setting LValue from a non-LValue?\"" , "clang/lib/AST/ExprConstant.cpp", 1575, __extension__ __PRETTY_FUNCTION__ )); | |||
1576 | Base = V.getLValueBase(); | |||
1577 | Offset = V.getLValueOffset(); | |||
1578 | InvalidBase = false; | |||
1579 | Designator = SubobjectDesignator(Ctx, V); | |||
1580 | IsNullPtr = V.isNullPointer(); | |||
1581 | } | |||
1582 | ||||
1583 | void set(APValue::LValueBase B, bool BInvalid = false) { | |||
1584 | #ifndef NDEBUG | |||
1585 | // We only allow a few types of invalid bases. Enforce that here. | |||
1586 | if (BInvalid) { | |||
1587 | const auto *E = B.get<const Expr *>(); | |||
1588 | assert((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) &&(static_cast <bool> ((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall (E)) && "Unexpected type of invalid base") ? void (0) : __assert_fail ("(isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) && \"Unexpected type of invalid base\"" , "clang/lib/AST/ExprConstant.cpp", 1589, __extension__ __PRETTY_FUNCTION__ )) | |||
1589 | "Unexpected type of invalid base")(static_cast <bool> ((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall (E)) && "Unexpected type of invalid base") ? void (0) : __assert_fail ("(isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) && \"Unexpected type of invalid base\"" , "clang/lib/AST/ExprConstant.cpp", 1589, __extension__ __PRETTY_FUNCTION__ )); | |||
1590 | } | |||
1591 | #endif | |||
1592 | ||||
1593 | Base = B; | |||
1594 | Offset = CharUnits::fromQuantity(0); | |||
1595 | InvalidBase = BInvalid; | |||
1596 | Designator = SubobjectDesignator(getType(B)); | |||
1597 | IsNullPtr = false; | |||
1598 | } | |||
1599 | ||||
1600 | void setNull(ASTContext &Ctx, QualType PointerTy) { | |||
1601 | Base = (const ValueDecl *)nullptr; | |||
1602 | Offset = | |||
1603 | CharUnits::fromQuantity(Ctx.getTargetNullPointerValue(PointerTy)); | |||
1604 | InvalidBase = false; | |||
1605 | Designator = SubobjectDesignator(PointerTy->getPointeeType()); | |||
1606 | IsNullPtr = true; | |||
1607 | } | |||
1608 | ||||
1609 | void setInvalid(APValue::LValueBase B, unsigned I = 0) { | |||
1610 | set(B, true); | |||
1611 | } | |||
1612 | ||||
1613 | std::string toString(ASTContext &Ctx, QualType T) const { | |||
1614 | APValue Printable; | |||
1615 | moveInto(Printable); | |||
1616 | return Printable.getAsString(Ctx, T); | |||
1617 | } | |||
1618 | ||||
1619 | private: | |||
1620 | // Check that this LValue is not based on a null pointer. If it is, produce | |||
1621 | // a diagnostic and mark the designator as invalid. | |||
1622 | template <typename GenDiagType> | |||
1623 | bool checkNullPointerDiagnosingWith(const GenDiagType &GenDiag) { | |||
1624 | if (Designator.Invalid) | |||
1625 | return false; | |||
1626 | if (IsNullPtr) { | |||
1627 | GenDiag(); | |||
1628 | Designator.setInvalid(); | |||
1629 | return false; | |||
1630 | } | |||
1631 | return true; | |||
1632 | } | |||
1633 | ||||
1634 | public: | |||
1635 | bool checkNullPointer(EvalInfo &Info, const Expr *E, | |||
1636 | CheckSubobjectKind CSK) { | |||
1637 | return checkNullPointerDiagnosingWith([&Info, E, CSK] { | |||
1638 | Info.CCEDiag(E, diag::note_constexpr_null_subobject) << CSK; | |||
1639 | }); | |||
1640 | } | |||
1641 | ||||
1642 | bool checkNullPointerForFoldAccess(EvalInfo &Info, const Expr *E, | |||
1643 | AccessKinds AK) { | |||
1644 | return checkNullPointerDiagnosingWith([&Info, E, AK] { | |||
1645 | Info.FFDiag(E, diag::note_constexpr_access_null) << AK; | |||
1646 | }); | |||
1647 | } | |||
1648 | ||||
1649 | // Check this LValue refers to an object. If not, set the designator to be | |||
1650 | // invalid and emit a diagnostic. | |||
1651 | bool checkSubobject(EvalInfo &Info, const Expr *E, CheckSubobjectKind CSK) { | |||
1652 | return (CSK == CSK_ArrayToPointer || checkNullPointer(Info, E, CSK)) && | |||
1653 | Designator.checkSubobject(Info, E, CSK); | |||
1654 | } | |||
1655 | ||||
1656 | void addDecl(EvalInfo &Info, const Expr *E, | |||
1657 | const Decl *D, bool Virtual = false) { | |||
1658 | if (checkSubobject(Info, E, isa<FieldDecl>(D) ? CSK_Field : CSK_Base)) | |||
1659 | Designator.addDeclUnchecked(D, Virtual); | |||
1660 | } | |||
1661 | void addUnsizedArray(EvalInfo &Info, const Expr *E, QualType ElemTy) { | |||
1662 | if (!Designator.Entries.empty()) { | |||
1663 | Info.CCEDiag(E, diag::note_constexpr_unsupported_unsized_array); | |||
1664 | Designator.setInvalid(); | |||
1665 | return; | |||
1666 | } | |||
1667 | if (checkSubobject(Info, E, CSK_ArrayToPointer)) { | |||
1668 | assert(getType(Base)->isPointerType() || getType(Base)->isArrayType())(static_cast <bool> (getType(Base)->isPointerType() || getType(Base)->isArrayType()) ? void (0) : __assert_fail ( "getType(Base)->isPointerType() || getType(Base)->isArrayType()" , "clang/lib/AST/ExprConstant.cpp", 1668, __extension__ __PRETTY_FUNCTION__ )); | |||
1669 | Designator.FirstEntryIsAnUnsizedArray = true; | |||
1670 | Designator.addUnsizedArrayUnchecked(ElemTy); | |||
1671 | } | |||
1672 | } | |||
1673 | void addArray(EvalInfo &Info, const Expr *E, const ConstantArrayType *CAT) { | |||
1674 | if (checkSubobject(Info, E, CSK_ArrayToPointer)) | |||
1675 | Designator.addArrayUnchecked(CAT); | |||
1676 | } | |||
1677 | void addComplex(EvalInfo &Info, const Expr *E, QualType EltTy, bool Imag) { | |||
1678 | if (checkSubobject(Info, E, Imag ? CSK_Imag : CSK_Real)) | |||
1679 | Designator.addComplexUnchecked(EltTy, Imag); | |||
1680 | } | |||
1681 | void clearIsNullPointer() { | |||
1682 | IsNullPtr = false; | |||
1683 | } | |||
1684 | void adjustOffsetAndIndex(EvalInfo &Info, const Expr *E, | |||
1685 | const APSInt &Index, CharUnits ElementSize) { | |||
1686 | // An index of 0 has no effect. (In C, adding 0 to a null pointer is UB, | |||
1687 | // but we're not required to diagnose it and it's valid in C++.) | |||
1688 | if (!Index) | |||
1689 | return; | |||
1690 | ||||
1691 | // Compute the new offset in the appropriate width, wrapping at 64 bits. | |||
1692 | // FIXME: When compiling for a 32-bit target, we should use 32-bit | |||
1693 | // offsets. | |||
1694 | uint64_t Offset64 = Offset.getQuantity(); | |||
1695 | uint64_t ElemSize64 = ElementSize.getQuantity(); | |||
1696 | uint64_t Index64 = Index.extOrTrunc(64).getZExtValue(); | |||
1697 | Offset = CharUnits::fromQuantity(Offset64 + ElemSize64 * Index64); | |||
1698 | ||||
1699 | if (checkNullPointer(Info, E, CSK_ArrayIndex)) | |||
1700 | Designator.adjustIndex(Info, E, Index); | |||
1701 | clearIsNullPointer(); | |||
1702 | } | |||
1703 | void adjustOffset(CharUnits N) { | |||
1704 | Offset += N; | |||
1705 | if (N.getQuantity()) | |||
1706 | clearIsNullPointer(); | |||
1707 | } | |||
1708 | }; | |||
1709 | ||||
1710 | struct MemberPtr { | |||
1711 | MemberPtr() {} | |||
1712 | explicit MemberPtr(const ValueDecl *Decl) | |||
1713 | : DeclAndIsDerivedMember(Decl, false) {} | |||
1714 | ||||
1715 | /// The member or (direct or indirect) field referred to by this member | |||
1716 | /// pointer, or 0 if this is a null member pointer. | |||
1717 | const ValueDecl *getDecl() const { | |||
1718 | return DeclAndIsDerivedMember.getPointer(); | |||
1719 | } | |||
1720 | /// Is this actually a member of some type derived from the relevant class? | |||
1721 | bool isDerivedMember() const { | |||
1722 | return DeclAndIsDerivedMember.getInt(); | |||
1723 | } | |||
1724 | /// Get the class which the declaration actually lives in. | |||
1725 | const CXXRecordDecl *getContainingRecord() const { | |||
1726 | return cast<CXXRecordDecl>( | |||
1727 | DeclAndIsDerivedMember.getPointer()->getDeclContext()); | |||
1728 | } | |||
1729 | ||||
1730 | void moveInto(APValue &V) const { | |||
1731 | V = APValue(getDecl(), isDerivedMember(), Path); | |||
1732 | } | |||
1733 | void setFrom(const APValue &V) { | |||
1734 | assert(V.isMemberPointer())(static_cast <bool> (V.isMemberPointer()) ? void (0) : __assert_fail ("V.isMemberPointer()", "clang/lib/AST/ExprConstant.cpp", 1734 , __extension__ __PRETTY_FUNCTION__)); | |||
1735 | DeclAndIsDerivedMember.setPointer(V.getMemberPointerDecl()); | |||
1736 | DeclAndIsDerivedMember.setInt(V.isMemberPointerToDerivedMember()); | |||
1737 | Path.clear(); | |||
1738 | ArrayRef<const CXXRecordDecl*> P = V.getMemberPointerPath(); | |||
1739 | Path.insert(Path.end(), P.begin(), P.end()); | |||
1740 | } | |||
1741 | ||||
1742 | /// DeclAndIsDerivedMember - The member declaration, and a flag indicating | |||
1743 | /// whether the member is a member of some class derived from the class type | |||
1744 | /// of the member pointer. | |||
1745 | llvm::PointerIntPair<const ValueDecl*, 1, bool> DeclAndIsDerivedMember; | |||
1746 | /// Path - The path of base/derived classes from the member declaration's | |||
1747 | /// class (exclusive) to the class type of the member pointer (inclusive). | |||
1748 | SmallVector<const CXXRecordDecl*, 4> Path; | |||
1749 | ||||
1750 | /// Perform a cast towards the class of the Decl (either up or down the | |||
1751 | /// hierarchy). | |||
1752 | bool castBack(const CXXRecordDecl *Class) { | |||
1753 | assert(!Path.empty())(static_cast <bool> (!Path.empty()) ? void (0) : __assert_fail ("!Path.empty()", "clang/lib/AST/ExprConstant.cpp", 1753, __extension__ __PRETTY_FUNCTION__)); | |||
1754 | const CXXRecordDecl *Expected; | |||
1755 | if (Path.size() >= 2) | |||
1756 | Expected = Path[Path.size() - 2]; | |||
1757 | else | |||
1758 | Expected = getContainingRecord(); | |||
1759 | if (Expected->getCanonicalDecl() != Class->getCanonicalDecl()) { | |||
1760 | // C++11 [expr.static.cast]p12: In a conversion from (D::*) to (B::*), | |||
1761 | // if B does not contain the original member and is not a base or | |||
1762 | // derived class of the class containing the original member, the result | |||
1763 | // of the cast is undefined. | |||
1764 | // C++11 [conv.mem]p2 does not cover this case for a cast from (B::*) to | |||
1765 | // (D::*). We consider that to be a language defect. | |||
1766 | return false; | |||
1767 | } | |||
1768 | Path.pop_back(); | |||
1769 | return true; | |||
1770 | } | |||
1771 | /// Perform a base-to-derived member pointer cast. | |||
1772 | bool castToDerived(const CXXRecordDecl *Derived) { | |||
1773 | if (!getDecl()) | |||
1774 | return true; | |||
1775 | if (!isDerivedMember()) { | |||
1776 | Path.push_back(Derived); | |||
1777 | return true; | |||
1778 | } | |||
1779 | if (!castBack(Derived)) | |||
1780 | return false; | |||
1781 | if (Path.empty()) | |||
1782 | DeclAndIsDerivedMember.setInt(false); | |||
1783 | return true; | |||
1784 | } | |||
1785 | /// Perform a derived-to-base member pointer cast. | |||
1786 | bool castToBase(const CXXRecordDecl *Base) { | |||
1787 | if (!getDecl()) | |||
1788 | return true; | |||
1789 | if (Path.empty()) | |||
1790 | DeclAndIsDerivedMember.setInt(true); | |||
1791 | if (isDerivedMember()) { | |||
1792 | Path.push_back(Base); | |||
1793 | return true; | |||
1794 | } | |||
1795 | return castBack(Base); | |||
1796 | } | |||
1797 | }; | |||
1798 | ||||
1799 | /// Compare two member pointers, which are assumed to be of the same type. | |||
1800 | static bool operator==(const MemberPtr &LHS, const MemberPtr &RHS) { | |||
1801 | if (!LHS.getDecl() || !RHS.getDecl()) | |||
1802 | return !LHS.getDecl() && !RHS.getDecl(); | |||
1803 | if (LHS.getDecl()->getCanonicalDecl() != RHS.getDecl()->getCanonicalDecl()) | |||
1804 | return false; | |||
1805 | return LHS.Path == RHS.Path; | |||
1806 | } | |||
1807 | } | |||
1808 | ||||
1809 | static bool Evaluate(APValue &Result, EvalInfo &Info, const Expr *E); | |||
1810 | static bool EvaluateInPlace(APValue &Result, EvalInfo &Info, | |||
1811 | const LValue &This, const Expr *E, | |||
1812 | bool AllowNonLiteralTypes = false); | |||
1813 | static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info, | |||
1814 | bool InvalidBaseOK = false); | |||
1815 | static bool EvaluatePointer(const Expr *E, LValue &Result, EvalInfo &Info, | |||
1816 | bool InvalidBaseOK = false); | |||
1817 | static bool EvaluateMemberPointer(const Expr *E, MemberPtr &Result, | |||
1818 | EvalInfo &Info); | |||
1819 | static bool EvaluateTemporary(const Expr *E, LValue &Result, EvalInfo &Info); | |||
1820 | static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info); | |||
1821 | static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result, | |||
1822 | EvalInfo &Info); | |||
1823 | static bool EvaluateFloat(const Expr *E, APFloat &Result, EvalInfo &Info); | |||
1824 | static bool EvaluateComplex(const Expr *E, ComplexValue &Res, EvalInfo &Info); | |||
1825 | static bool EvaluateAtomic(const Expr *E, const LValue *This, APValue &Result, | |||
1826 | EvalInfo &Info); | |||
1827 | static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result); | |||
1828 | static bool EvaluateBuiltinStrLen(const Expr *E, uint64_t &Result, | |||
1829 | EvalInfo &Info); | |||
1830 | ||||
1831 | /// Evaluate an integer or fixed point expression into an APResult. | |||
1832 | static bool EvaluateFixedPointOrInteger(const Expr *E, APFixedPoint &Result, | |||
1833 | EvalInfo &Info); | |||
1834 | ||||
1835 | /// Evaluate only a fixed point expression into an APResult. | |||
1836 | static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result, | |||
1837 | EvalInfo &Info); | |||
1838 | ||||
1839 | //===----------------------------------------------------------------------===// | |||
1840 | // Misc utilities | |||
1841 | //===----------------------------------------------------------------------===// | |||
1842 | ||||
1843 | /// Negate an APSInt in place, converting it to a signed form if necessary, and | |||
1844 | /// preserving its value (by extending by up to one bit as needed). | |||
1845 | static void negateAsSigned(APSInt &Int) { | |||
1846 | if (Int.isUnsigned() || Int.isMinSignedValue()) { | |||
1847 | Int = Int.extend(Int.getBitWidth() + 1); | |||
1848 | Int.setIsSigned(true); | |||
1849 | } | |||
1850 | Int = -Int; | |||
1851 | } | |||
1852 | ||||
1853 | template<typename KeyT> | |||
1854 | APValue &CallStackFrame::createTemporary(const KeyT *Key, QualType T, | |||
1855 | ScopeKind Scope, LValue &LV) { | |||
1856 | unsigned Version = getTempVersion(); | |||
1857 | APValue::LValueBase Base(Key, Index, Version); | |||
1858 | LV.set(Base); | |||
1859 | return createLocal(Base, Key, T, Scope); | |||
1860 | } | |||
1861 | ||||
1862 | /// Allocate storage for a parameter of a function call made in this frame. | |||
1863 | APValue &CallStackFrame::createParam(CallRef Args, const ParmVarDecl *PVD, | |||
1864 | LValue &LV) { | |||
1865 | assert(Args.CallIndex == Index && "creating parameter in wrong frame")(static_cast <bool> (Args.CallIndex == Index && "creating parameter in wrong frame") ? void (0) : __assert_fail ("Args.CallIndex == Index && \"creating parameter in wrong frame\"" , "clang/lib/AST/ExprConstant.cpp", 1865, __extension__ __PRETTY_FUNCTION__ )); | |||
1866 | APValue::LValueBase Base(PVD, Index, Args.Version); | |||
1867 | LV.set(Base); | |||
1868 | // We always destroy parameters at the end of the call, even if we'd allow | |||
1869 | // them to live to the end of the full-expression at runtime, in order to | |||
1870 | // give portable results and match other compilers. | |||
1871 | return createLocal(Base, PVD, PVD->getType(), ScopeKind::Call); | |||
1872 | } | |||
1873 | ||||
1874 | APValue &CallStackFrame::createLocal(APValue::LValueBase Base, const void *Key, | |||
1875 | QualType T, ScopeKind Scope) { | |||
1876 | assert(Base.getCallIndex() == Index && "lvalue for wrong frame")(static_cast <bool> (Base.getCallIndex() == Index && "lvalue for wrong frame") ? void (0) : __assert_fail ("Base.getCallIndex() == Index && \"lvalue for wrong frame\"" , "clang/lib/AST/ExprConstant.cpp", 1876, __extension__ __PRETTY_FUNCTION__ )); | |||
1877 | unsigned Version = Base.getVersion(); | |||
1878 | APValue &Result = Temporaries[MapKeyTy(Key, Version)]; | |||
1879 | assert(Result.isAbsent() && "local created multiple times")(static_cast <bool> (Result.isAbsent() && "local created multiple times" ) ? void (0) : __assert_fail ("Result.isAbsent() && \"local created multiple times\"" , "clang/lib/AST/ExprConstant.cpp", 1879, __extension__ __PRETTY_FUNCTION__ )); | |||
1880 | ||||
1881 | // If we're creating a local immediately in the operand of a speculative | |||
1882 | // evaluation, don't register a cleanup to be run outside the speculative | |||
1883 | // evaluation context, since we won't actually be able to initialize this | |||
1884 | // object. | |||
1885 | if (Index <= Info.SpeculativeEvaluationDepth) { | |||
1886 | if (T.isDestructedType()) | |||
1887 | Info.noteSideEffect(); | |||
1888 | } else { | |||
1889 | Info.CleanupStack.push_back(Cleanup(&Result, Base, T, Scope)); | |||
1890 | } | |||
1891 | return Result; | |||
1892 | } | |||
1893 | ||||
1894 | APValue *EvalInfo::createHeapAlloc(const Expr *E, QualType T, LValue &LV) { | |||
1895 | if (NumHeapAllocs > DynamicAllocLValue::getMaxIndex()) { | |||
1896 | FFDiag(E, diag::note_constexpr_heap_alloc_limit_exceeded); | |||
1897 | return nullptr; | |||
1898 | } | |||
1899 | ||||
1900 | DynamicAllocLValue DA(NumHeapAllocs++); | |||
1901 | LV.set(APValue::LValueBase::getDynamicAlloc(DA, T)); | |||
1902 | auto Result = HeapAllocs.emplace(std::piecewise_construct, | |||
1903 | std::forward_as_tuple(DA), std::tuple<>()); | |||
1904 | assert(Result.second && "reused a heap alloc index?")(static_cast <bool> (Result.second && "reused a heap alloc index?" ) ? void (0) : __assert_fail ("Result.second && \"reused a heap alloc index?\"" , "clang/lib/AST/ExprConstant.cpp", 1904, __extension__ __PRETTY_FUNCTION__ )); | |||
1905 | Result.first->second.AllocExpr = E; | |||
1906 | return &Result.first->second.Value; | |||
1907 | } | |||
1908 | ||||
1909 | /// Produce a string describing the given constexpr call. | |||
1910 | void CallStackFrame::describe(raw_ostream &Out) { | |||
1911 | unsigned ArgIndex = 0; | |||
1912 | bool IsMemberCall = isa<CXXMethodDecl>(Callee) && | |||
1913 | !isa<CXXConstructorDecl>(Callee) && | |||
1914 | cast<CXXMethodDecl>(Callee)->isInstance(); | |||
1915 | ||||
1916 | if (!IsMemberCall) | |||
1917 | Out << *Callee << '('; | |||
1918 | ||||
1919 | if (This && IsMemberCall) { | |||
1920 | APValue Val; | |||
1921 | This->moveInto(Val); | |||
1922 | Val.printPretty(Out, Info.Ctx, | |||
1923 | This->Designator.MostDerivedType); | |||
1924 | // FIXME: Add parens around Val if needed. | |||
1925 | Out << "->" << *Callee << '('; | |||
1926 | IsMemberCall = false; | |||
1927 | } | |||
1928 | ||||
1929 | for (FunctionDecl::param_const_iterator I = Callee->param_begin(), | |||
1930 | E = Callee->param_end(); I != E; ++I, ++ArgIndex) { | |||
1931 | if (ArgIndex > (unsigned)IsMemberCall) | |||
1932 | Out << ", "; | |||
1933 | ||||
1934 | const ParmVarDecl *Param = *I; | |||
1935 | APValue *V = Info.getParamSlot(Arguments, Param); | |||
1936 | if (V) | |||
1937 | V->printPretty(Out, Info.Ctx, Param->getType()); | |||
1938 | else | |||
1939 | Out << "<...>"; | |||
1940 | ||||
1941 | if (ArgIndex == 0 && IsMemberCall) | |||
1942 | Out << "->" << *Callee << '('; | |||
1943 | } | |||
1944 | ||||
1945 | Out << ')'; | |||
1946 | } | |||
1947 | ||||
1948 | /// Evaluate an expression to see if it had side-effects, and discard its | |||
1949 | /// result. | |||
1950 | /// \return \c true if the caller should keep evaluating. | |||
1951 | static bool EvaluateIgnoredValue(EvalInfo &Info, const Expr *E) { | |||
1952 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 1952, __extension__ __PRETTY_FUNCTION__)); | |||
1953 | APValue Scratch; | |||
1954 | if (!Evaluate(Scratch, Info, E)) | |||
1955 | // We don't need the value, but we might have skipped a side effect here. | |||
1956 | return Info.noteSideEffect(); | |||
1957 | return true; | |||
1958 | } | |||
1959 | ||||
1960 | /// Should this call expression be treated as a no-op? | |||
1961 | static bool IsNoOpCall(const CallExpr *E) { | |||
1962 | unsigned Builtin = E->getBuiltinCallee(); | |||
1963 | return (Builtin == Builtin::BI__builtin___CFStringMakeConstantString || | |||
1964 | Builtin == Builtin::BI__builtin___NSStringMakeConstantString || | |||
1965 | Builtin == Builtin::BI__builtin_function_start); | |||
1966 | } | |||
1967 | ||||
1968 | static bool IsGlobalLValue(APValue::LValueBase B) { | |||
1969 | // C++11 [expr.const]p3 An address constant expression is a prvalue core | |||
1970 | // constant expression of pointer type that evaluates to... | |||
1971 | ||||
1972 | // ... a null pointer value, or a prvalue core constant expression of type | |||
1973 | // std::nullptr_t. | |||
1974 | if (!B) return true; | |||
1975 | ||||
1976 | if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) { | |||
1977 | // ... the address of an object with static storage duration, | |||
1978 | if (const VarDecl *VD = dyn_cast<VarDecl>(D)) | |||
1979 | return VD->hasGlobalStorage(); | |||
1980 | if (isa<TemplateParamObjectDecl>(D)) | |||
1981 | return true; | |||
1982 | // ... the address of a function, | |||
1983 | // ... the address of a GUID [MS extension], | |||
1984 | // ... the address of an unnamed global constant | |||
1985 | return isa<FunctionDecl, MSGuidDecl, UnnamedGlobalConstantDecl>(D); | |||
1986 | } | |||
1987 | ||||
1988 | if (B.is<TypeInfoLValue>() || B.is<DynamicAllocLValue>()) | |||
1989 | return true; | |||
1990 | ||||
1991 | const Expr *E = B.get<const Expr*>(); | |||
1992 | switch (E->getStmtClass()) { | |||
1993 | default: | |||
1994 | return false; | |||
1995 | case Expr::CompoundLiteralExprClass: { | |||
1996 | const CompoundLiteralExpr *CLE = cast<CompoundLiteralExpr>(E); | |||
1997 | return CLE->isFileScope() && CLE->isLValue(); | |||
1998 | } | |||
1999 | case Expr::MaterializeTemporaryExprClass: | |||
2000 | // A materialized temporary might have been lifetime-extended to static | |||
2001 | // storage duration. | |||
2002 | return cast<MaterializeTemporaryExpr>(E)->getStorageDuration() == SD_Static; | |||
2003 | // A string literal has static storage duration. | |||
2004 | case Expr::StringLiteralClass: | |||
2005 | case Expr::PredefinedExprClass: | |||
2006 | case Expr::ObjCStringLiteralClass: | |||
2007 | case Expr::ObjCEncodeExprClass: | |||
2008 | return true; | |||
2009 | case Expr::ObjCBoxedExprClass: | |||
2010 | return cast<ObjCBoxedExpr>(E)->isExpressibleAsConstantInitializer(); | |||
2011 | case Expr::CallExprClass: | |||
2012 | return IsNoOpCall(cast<CallExpr>(E)); | |||
2013 | // For GCC compatibility, &&label has static storage duration. | |||
2014 | case Expr::AddrLabelExprClass: | |||
2015 | return true; | |||
2016 | // A Block literal expression may be used as the initialization value for | |||
2017 | // Block variables at global or local static scope. | |||
2018 | case Expr::BlockExprClass: | |||
2019 | return !cast<BlockExpr>(E)->getBlockDecl()->hasCaptures(); | |||
2020 | // The APValue generated from a __builtin_source_location will be emitted as a | |||
2021 | // literal. | |||
2022 | case Expr::SourceLocExprClass: | |||
2023 | return true; | |||
2024 | case Expr::ImplicitValueInitExprClass: | |||
2025 | // FIXME: | |||
2026 | // We can never form an lvalue with an implicit value initialization as its | |||
2027 | // base through expression evaluation, so these only appear in one case: the | |||
2028 | // implicit variable declaration we invent when checking whether a constexpr | |||
2029 | // constructor can produce a constant expression. We must assume that such | |||
2030 | // an expression might be a global lvalue. | |||
2031 | return true; | |||
2032 | } | |||
2033 | } | |||
2034 | ||||
2035 | static const ValueDecl *GetLValueBaseDecl(const LValue &LVal) { | |||
2036 | return LVal.Base.dyn_cast<const ValueDecl*>(); | |||
2037 | } | |||
2038 | ||||
2039 | static bool IsLiteralLValue(const LValue &Value) { | |||
2040 | if (Value.getLValueCallIndex()) | |||
2041 | return false; | |||
2042 | const Expr *E = Value.Base.dyn_cast<const Expr*>(); | |||
2043 | return E && !isa<MaterializeTemporaryExpr>(E); | |||
2044 | } | |||
2045 | ||||
2046 | static bool IsWeakLValue(const LValue &Value) { | |||
2047 | const ValueDecl *Decl = GetLValueBaseDecl(Value); | |||
2048 | return Decl && Decl->isWeak(); | |||
2049 | } | |||
2050 | ||||
2051 | static bool isZeroSized(const LValue &Value) { | |||
2052 | const ValueDecl *Decl = GetLValueBaseDecl(Value); | |||
2053 | if (Decl && isa<VarDecl>(Decl)) { | |||
2054 | QualType Ty = Decl->getType(); | |||
2055 | if (Ty->isArrayType()) | |||
2056 | return Ty->isIncompleteType() || | |||
2057 | Decl->getASTContext().getTypeSize(Ty) == 0; | |||
2058 | } | |||
2059 | return false; | |||
2060 | } | |||
2061 | ||||
2062 | static bool HasSameBase(const LValue &A, const LValue &B) { | |||
2063 | if (!A.getLValueBase()) | |||
2064 | return !B.getLValueBase(); | |||
2065 | if (!B.getLValueBase()) | |||
2066 | return false; | |||
2067 | ||||
2068 | if (A.getLValueBase().getOpaqueValue() != | |||
2069 | B.getLValueBase().getOpaqueValue()) | |||
2070 | return false; | |||
2071 | ||||
2072 | return A.getLValueCallIndex() == B.getLValueCallIndex() && | |||
2073 | A.getLValueVersion() == B.getLValueVersion(); | |||
2074 | } | |||
2075 | ||||
2076 | static void NoteLValueLocation(EvalInfo &Info, APValue::LValueBase Base) { | |||
2077 | assert(Base && "no location for a null lvalue")(static_cast <bool> (Base && "no location for a null lvalue" ) ? void (0) : __assert_fail ("Base && \"no location for a null lvalue\"" , "clang/lib/AST/ExprConstant.cpp", 2077, __extension__ __PRETTY_FUNCTION__ )); | |||
2078 | const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>(); | |||
2079 | ||||
2080 | // For a parameter, find the corresponding call stack frame (if it still | |||
2081 | // exists), and point at the parameter of the function definition we actually | |||
2082 | // invoked. | |||
2083 | if (auto *PVD = dyn_cast_or_null<ParmVarDecl>(VD)) { | |||
2084 | unsigned Idx = PVD->getFunctionScopeIndex(); | |||
2085 | for (CallStackFrame *F = Info.CurrentCall; F; F = F->Caller) { | |||
2086 | if (F->Arguments.CallIndex == Base.getCallIndex() && | |||
2087 | F->Arguments.Version == Base.getVersion() && F->Callee && | |||
2088 | Idx < F->Callee->getNumParams()) { | |||
2089 | VD = F->Callee->getParamDecl(Idx); | |||
2090 | break; | |||
2091 | } | |||
2092 | } | |||
2093 | } | |||
2094 | ||||
2095 | if (VD) | |||
2096 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
2097 | else if (const Expr *E = Base.dyn_cast<const Expr*>()) | |||
2098 | Info.Note(E->getExprLoc(), diag::note_constexpr_temporary_here); | |||
2099 | else if (DynamicAllocLValue DA = Base.dyn_cast<DynamicAllocLValue>()) { | |||
2100 | // FIXME: Produce a note for dangling pointers too. | |||
2101 | if (std::optional<DynAlloc *> Alloc = Info.lookupDynamicAlloc(DA)) | |||
2102 | Info.Note((*Alloc)->AllocExpr->getExprLoc(), | |||
2103 | diag::note_constexpr_dynamic_alloc_here); | |||
2104 | } | |||
2105 | // We have no information to show for a typeid(T) object. | |||
2106 | } | |||
2107 | ||||
2108 | enum class CheckEvaluationResultKind { | |||
2109 | ConstantExpression, | |||
2110 | FullyInitialized, | |||
2111 | }; | |||
2112 | ||||
2113 | /// Materialized temporaries that we've already checked to determine if they're | |||
2114 | /// initializsed by a constant expression. | |||
2115 | using CheckedTemporaries = | |||
2116 | llvm::SmallPtrSet<const MaterializeTemporaryExpr *, 8>; | |||
2117 | ||||
2118 | static bool CheckEvaluationResult(CheckEvaluationResultKind CERK, | |||
2119 | EvalInfo &Info, SourceLocation DiagLoc, | |||
2120 | QualType Type, const APValue &Value, | |||
2121 | ConstantExprKind Kind, | |||
2122 | SourceLocation SubobjectLoc, | |||
2123 | CheckedTemporaries &CheckedTemps); | |||
2124 | ||||
2125 | /// Check that this reference or pointer core constant expression is a valid | |||
2126 | /// value for an address or reference constant expression. Return true if we | |||
2127 | /// can fold this expression, whether or not it's a constant expression. | |||
2128 | static bool CheckLValueConstantExpression(EvalInfo &Info, SourceLocation Loc, | |||
2129 | QualType Type, const LValue &LVal, | |||
2130 | ConstantExprKind Kind, | |||
2131 | CheckedTemporaries &CheckedTemps) { | |||
2132 | bool IsReferenceType = Type->isReferenceType(); | |||
2133 | ||||
2134 | APValue::LValueBase Base = LVal.getLValueBase(); | |||
2135 | const SubobjectDesignator &Designator = LVal.getLValueDesignator(); | |||
2136 | ||||
2137 | const Expr *BaseE = Base.dyn_cast<const Expr *>(); | |||
2138 | const ValueDecl *BaseVD = Base.dyn_cast<const ValueDecl*>(); | |||
2139 | ||||
2140 | // Additional restrictions apply in a template argument. We only enforce the | |||
2141 | // C++20 restrictions here; additional syntactic and semantic restrictions | |||
2142 | // are applied elsewhere. | |||
2143 | if (isTemplateArgument(Kind)) { | |||
2144 | int InvalidBaseKind = -1; | |||
2145 | StringRef Ident; | |||
2146 | if (Base.is<TypeInfoLValue>()) | |||
2147 | InvalidBaseKind = 0; | |||
2148 | else if (isa_and_nonnull<StringLiteral>(BaseE)) | |||
2149 | InvalidBaseKind = 1; | |||
2150 | else if (isa_and_nonnull<MaterializeTemporaryExpr>(BaseE) || | |||
2151 | isa_and_nonnull<LifetimeExtendedTemporaryDecl>(BaseVD)) | |||
2152 | InvalidBaseKind = 2; | |||
2153 | else if (auto *PE = dyn_cast_or_null<PredefinedExpr>(BaseE)) { | |||
2154 | InvalidBaseKind = 3; | |||
2155 | Ident = PE->getIdentKindName(); | |||
2156 | } | |||
2157 | ||||
2158 | if (InvalidBaseKind != -1) { | |||
2159 | Info.FFDiag(Loc, diag::note_constexpr_invalid_template_arg) | |||
2160 | << IsReferenceType << !Designator.Entries.empty() << InvalidBaseKind | |||
2161 | << Ident; | |||
2162 | return false; | |||
2163 | } | |||
2164 | } | |||
2165 | ||||
2166 | if (auto *FD = dyn_cast_or_null<FunctionDecl>(BaseVD)) { | |||
2167 | if (FD->isConsteval()) { | |||
2168 | Info.FFDiag(Loc, diag::note_consteval_address_accessible) | |||
2169 | << !Type->isAnyPointerType(); | |||
2170 | Info.Note(FD->getLocation(), diag::note_declared_at); | |||
2171 | return false; | |||
2172 | } | |||
2173 | } | |||
2174 | ||||
2175 | // Check that the object is a global. Note that the fake 'this' object we | |||
2176 | // manufacture when checking potential constant expressions is conservatively | |||
2177 | // assumed to be global here. | |||
2178 | if (!IsGlobalLValue(Base)) { | |||
2179 | if (Info.getLangOpts().CPlusPlus11) { | |||
2180 | Info.FFDiag(Loc, diag::note_constexpr_non_global, 1) | |||
2181 | << IsReferenceType << !Designator.Entries.empty() << !!BaseVD | |||
2182 | << BaseVD; | |||
2183 | auto *VarD = dyn_cast_or_null<VarDecl>(BaseVD); | |||
2184 | if (VarD && VarD->isConstexpr()) { | |||
2185 | // Non-static local constexpr variables have unintuitive semantics: | |||
2186 | // constexpr int a = 1; | |||
2187 | // constexpr const int *p = &a; | |||
2188 | // ... is invalid because the address of 'a' is not constant. Suggest | |||
2189 | // adding a 'static' in this case. | |||
2190 | Info.Note(VarD->getLocation(), diag::note_constexpr_not_static) | |||
2191 | << VarD | |||
2192 | << FixItHint::CreateInsertion(VarD->getBeginLoc(), "static "); | |||
2193 | } else { | |||
2194 | NoteLValueLocation(Info, Base); | |||
2195 | } | |||
2196 | } else { | |||
2197 | Info.FFDiag(Loc); | |||
2198 | } | |||
2199 | // Don't allow references to temporaries to escape. | |||
2200 | return false; | |||
2201 | } | |||
2202 | assert((Info.checkingPotentialConstantExpression() ||(static_cast <bool> ((Info.checkingPotentialConstantExpression () || LVal.getLValueCallIndex() == 0) && "have call index for global lvalue" ) ? void (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\"" , "clang/lib/AST/ExprConstant.cpp", 2204, __extension__ __PRETTY_FUNCTION__ )) | |||
2203 | LVal.getLValueCallIndex() == 0) &&(static_cast <bool> ((Info.checkingPotentialConstantExpression () || LVal.getLValueCallIndex() == 0) && "have call index for global lvalue" ) ? void (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\"" , "clang/lib/AST/ExprConstant.cpp", 2204, __extension__ __PRETTY_FUNCTION__ )) | |||
2204 | "have call index for global lvalue")(static_cast <bool> ((Info.checkingPotentialConstantExpression () || LVal.getLValueCallIndex() == 0) && "have call index for global lvalue" ) ? void (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\"" , "clang/lib/AST/ExprConstant.cpp", 2204, __extension__ __PRETTY_FUNCTION__ )); | |||
2205 | ||||
2206 | if (Base.is<DynamicAllocLValue>()) { | |||
2207 | Info.FFDiag(Loc, diag::note_constexpr_dynamic_alloc) | |||
2208 | << IsReferenceType << !Designator.Entries.empty(); | |||
2209 | NoteLValueLocation(Info, Base); | |||
2210 | return false; | |||
2211 | } | |||
2212 | ||||
2213 | if (BaseVD) { | |||
2214 | if (const VarDecl *Var = dyn_cast<const VarDecl>(BaseVD)) { | |||
2215 | // Check if this is a thread-local variable. | |||
2216 | if (Var->getTLSKind()) | |||
2217 | // FIXME: Diagnostic! | |||
2218 | return false; | |||
2219 | ||||
2220 | // A dllimport variable never acts like a constant, unless we're | |||
2221 | // evaluating a value for use only in name mangling. | |||
2222 | if (!isForManglingOnly(Kind) && Var->hasAttr<DLLImportAttr>()) | |||
2223 | // FIXME: Diagnostic! | |||
2224 | return false; | |||
2225 | ||||
2226 | // In CUDA/HIP device compilation, only device side variables have | |||
2227 | // constant addresses. | |||
2228 | if (Info.getCtx().getLangOpts().CUDA && | |||
2229 | Info.getCtx().getLangOpts().CUDAIsDevice && | |||
2230 | Info.getCtx().CUDAConstantEvalCtx.NoWrongSidedVars) { | |||
2231 | if ((!Var->hasAttr<CUDADeviceAttr>() && | |||
2232 | !Var->hasAttr<CUDAConstantAttr>() && | |||
2233 | !Var->getType()->isCUDADeviceBuiltinSurfaceType() && | |||
2234 | !Var->getType()->isCUDADeviceBuiltinTextureType()) || | |||
2235 | Var->hasAttr<HIPManagedAttr>()) | |||
2236 | return false; | |||
2237 | } | |||
2238 | } | |||
2239 | if (const auto *FD = dyn_cast<const FunctionDecl>(BaseVD)) { | |||
2240 | // __declspec(dllimport) must be handled very carefully: | |||
2241 | // We must never initialize an expression with the thunk in C++. | |||
2242 | // Doing otherwise would allow the same id-expression to yield | |||
2243 | // different addresses for the same function in different translation | |||
2244 | // units. However, this means that we must dynamically initialize the | |||
2245 | // expression with the contents of the import address table at runtime. | |||
2246 | // | |||
2247 | // The C language has no notion of ODR; furthermore, it has no notion of | |||
2248 | // dynamic initialization. This means that we are permitted to | |||
2249 | // perform initialization with the address of the thunk. | |||
2250 | if (Info.getLangOpts().CPlusPlus && !isForManglingOnly(Kind) && | |||
2251 | FD->hasAttr<DLLImportAttr>()) | |||
2252 | // FIXME: Diagnostic! | |||
2253 | return false; | |||
2254 | } | |||
2255 | } else if (const auto *MTE = | |||
2256 | dyn_cast_or_null<MaterializeTemporaryExpr>(BaseE)) { | |||
2257 | if (CheckedTemps.insert(MTE).second) { | |||
2258 | QualType TempType = getType(Base); | |||
2259 | if (TempType.isDestructedType()) { | |||
2260 | Info.FFDiag(MTE->getExprLoc(), | |||
2261 | diag::note_constexpr_unsupported_temporary_nontrivial_dtor) | |||
2262 | << TempType; | |||
2263 | return false; | |||
2264 | } | |||
2265 | ||||
2266 | APValue *V = MTE->getOrCreateValue(false); | |||
2267 | assert(V && "evasluation result refers to uninitialised temporary")(static_cast <bool> (V && "evasluation result refers to uninitialised temporary" ) ? void (0) : __assert_fail ("V && \"evasluation result refers to uninitialised temporary\"" , "clang/lib/AST/ExprConstant.cpp", 2267, __extension__ __PRETTY_FUNCTION__ )); | |||
2268 | if (!CheckEvaluationResult(CheckEvaluationResultKind::ConstantExpression, | |||
2269 | Info, MTE->getExprLoc(), TempType, *V, | |||
2270 | Kind, SourceLocation(), CheckedTemps)) | |||
2271 | return false; | |||
2272 | } | |||
2273 | } | |||
2274 | ||||
2275 | // Allow address constant expressions to be past-the-end pointers. This is | |||
2276 | // an extension: the standard requires them to point to an object. | |||
2277 | if (!IsReferenceType) | |||
2278 | return true; | |||
2279 | ||||
2280 | // A reference constant expression must refer to an object. | |||
2281 | if (!Base) { | |||
2282 | // FIXME: diagnostic | |||
2283 | Info.CCEDiag(Loc); | |||
2284 | return true; | |||
2285 | } | |||
2286 | ||||
2287 | // Does this refer one past the end of some object? | |||
2288 | if (!Designator.Invalid && Designator.isOnePastTheEnd()) { | |||
2289 | Info.FFDiag(Loc, diag::note_constexpr_past_end, 1) | |||
2290 | << !Designator.Entries.empty() << !!BaseVD << BaseVD; | |||
2291 | NoteLValueLocation(Info, Base); | |||
2292 | } | |||
2293 | ||||
2294 | return true; | |||
2295 | } | |||
2296 | ||||
2297 | /// Member pointers are constant expressions unless they point to a | |||
2298 | /// non-virtual dllimport member function. | |||
2299 | static bool CheckMemberPointerConstantExpression(EvalInfo &Info, | |||
2300 | SourceLocation Loc, | |||
2301 | QualType Type, | |||
2302 | const APValue &Value, | |||
2303 | ConstantExprKind Kind) { | |||
2304 | const ValueDecl *Member = Value.getMemberPointerDecl(); | |||
2305 | const auto *FD = dyn_cast_or_null<CXXMethodDecl>(Member); | |||
2306 | if (!FD) | |||
2307 | return true; | |||
2308 | if (FD->isConsteval()) { | |||
2309 | Info.FFDiag(Loc, diag::note_consteval_address_accessible) << /*pointer*/ 0; | |||
2310 | Info.Note(FD->getLocation(), diag::note_declared_at); | |||
2311 | return false; | |||
2312 | } | |||
2313 | return isForManglingOnly(Kind) || FD->isVirtual() || | |||
2314 | !FD->hasAttr<DLLImportAttr>(); | |||
2315 | } | |||
2316 | ||||
2317 | /// Check that this core constant expression is of literal type, and if not, | |||
2318 | /// produce an appropriate diagnostic. | |||
2319 | static bool CheckLiteralType(EvalInfo &Info, const Expr *E, | |||
2320 | const LValue *This = nullptr) { | |||
2321 | if (!E->isPRValue() || E->getType()->isLiteralType(Info.Ctx)) | |||
2322 | return true; | |||
2323 | ||||
2324 | // C++1y: A constant initializer for an object o [...] may also invoke | |||
2325 | // constexpr constructors for o and its subobjects even if those objects | |||
2326 | // are of non-literal class types. | |||
2327 | // | |||
2328 | // C++11 missed this detail for aggregates, so classes like this: | |||
2329 | // struct foo_t { union { int i; volatile int j; } u; }; | |||
2330 | // are not (obviously) initializable like so: | |||
2331 | // __attribute__((__require_constant_initialization__)) | |||
2332 | // static const foo_t x = {{0}}; | |||
2333 | // because "i" is a subobject with non-literal initialization (due to the | |||
2334 | // volatile member of the union). See: | |||
2335 | // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1677 | |||
2336 | // Therefore, we use the C++1y behavior. | |||
2337 | if (This && Info.EvaluatingDecl == This->getLValueBase()) | |||
2338 | return true; | |||
2339 | ||||
2340 | // Prvalue constant expressions must be of literal types. | |||
2341 | if (Info.getLangOpts().CPlusPlus11) | |||
2342 | Info.FFDiag(E, diag::note_constexpr_nonliteral) | |||
2343 | << E->getType(); | |||
2344 | else | |||
2345 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
2346 | return false; | |||
2347 | } | |||
2348 | ||||
2349 | static bool CheckEvaluationResult(CheckEvaluationResultKind CERK, | |||
2350 | EvalInfo &Info, SourceLocation DiagLoc, | |||
2351 | QualType Type, const APValue &Value, | |||
2352 | ConstantExprKind Kind, | |||
2353 | SourceLocation SubobjectLoc, | |||
2354 | CheckedTemporaries &CheckedTemps) { | |||
2355 | if (!Value.hasValue()) { | |||
2356 | Info.FFDiag(DiagLoc, diag::note_constexpr_uninitialized) | |||
2357 | << true << Type; | |||
2358 | if (SubobjectLoc.isValid()) | |||
2359 | Info.Note(SubobjectLoc, diag::note_constexpr_subobject_declared_here); | |||
2360 | return false; | |||
2361 | } | |||
2362 | ||||
2363 | // We allow _Atomic(T) to be initialized from anything that T can be | |||
2364 | // initialized from. | |||
2365 | if (const AtomicType *AT = Type->getAs<AtomicType>()) | |||
2366 | Type = AT->getValueType(); | |||
2367 | ||||
2368 | // Core issue 1454: For a literal constant expression of array or class type, | |||
2369 | // each subobject of its value shall have been initialized by a constant | |||
2370 | // expression. | |||
2371 | if (Value.isArray()) { | |||
2372 | QualType EltTy = Type->castAsArrayTypeUnsafe()->getElementType(); | |||
2373 | for (unsigned I = 0, N = Value.getArrayInitializedElts(); I != N; ++I) { | |||
2374 | if (!CheckEvaluationResult(CERK, Info, DiagLoc, EltTy, | |||
2375 | Value.getArrayInitializedElt(I), Kind, | |||
2376 | SubobjectLoc, CheckedTemps)) | |||
2377 | return false; | |||
2378 | } | |||
2379 | if (!Value.hasArrayFiller()) | |||
2380 | return true; | |||
2381 | return CheckEvaluationResult(CERK, Info, DiagLoc, EltTy, | |||
2382 | Value.getArrayFiller(), Kind, SubobjectLoc, | |||
2383 | CheckedTemps); | |||
2384 | } | |||
2385 | if (Value.isUnion() && Value.getUnionField()) { | |||
2386 | return CheckEvaluationResult( | |||
2387 | CERK, Info, DiagLoc, Value.getUnionField()->getType(), | |||
2388 | Value.getUnionValue(), Kind, Value.getUnionField()->getLocation(), | |||
2389 | CheckedTemps); | |||
2390 | } | |||
2391 | if (Value.isStruct()) { | |||
2392 | RecordDecl *RD = Type->castAs<RecordType>()->getDecl(); | |||
2393 | if (const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD)) { | |||
2394 | unsigned BaseIndex = 0; | |||
2395 | for (const CXXBaseSpecifier &BS : CD->bases()) { | |||
2396 | if (!CheckEvaluationResult(CERK, Info, DiagLoc, BS.getType(), | |||
2397 | Value.getStructBase(BaseIndex), Kind, | |||
2398 | BS.getBeginLoc(), CheckedTemps)) | |||
2399 | return false; | |||
2400 | ++BaseIndex; | |||
2401 | } | |||
2402 | } | |||
2403 | for (const auto *I : RD->fields()) { | |||
2404 | if (I->isUnnamedBitfield()) | |||
2405 | continue; | |||
2406 | ||||
2407 | if (!CheckEvaluationResult(CERK, Info, DiagLoc, I->getType(), | |||
2408 | Value.getStructField(I->getFieldIndex()), | |||
2409 | Kind, I->getLocation(), CheckedTemps)) | |||
2410 | return false; | |||
2411 | } | |||
2412 | } | |||
2413 | ||||
2414 | if (Value.isLValue() && | |||
2415 | CERK == CheckEvaluationResultKind::ConstantExpression) { | |||
2416 | LValue LVal; | |||
2417 | LVal.setFrom(Info.Ctx, Value); | |||
2418 | return CheckLValueConstantExpression(Info, DiagLoc, Type, LVal, Kind, | |||
2419 | CheckedTemps); | |||
2420 | } | |||
2421 | ||||
2422 | if (Value.isMemberPointer() && | |||
2423 | CERK == CheckEvaluationResultKind::ConstantExpression) | |||
2424 | return CheckMemberPointerConstantExpression(Info, DiagLoc, Type, Value, Kind); | |||
2425 | ||||
2426 | // Everything else is fine. | |||
2427 | return true; | |||
2428 | } | |||
2429 | ||||
2430 | /// Check that this core constant expression value is a valid value for a | |||
2431 | /// constant expression. If not, report an appropriate diagnostic. Does not | |||
2432 | /// check that the expression is of literal type. | |||
2433 | static bool CheckConstantExpression(EvalInfo &Info, SourceLocation DiagLoc, | |||
2434 | QualType Type, const APValue &Value, | |||
2435 | ConstantExprKind Kind) { | |||
2436 | // Nothing to check for a constant expression of type 'cv void'. | |||
2437 | if (Type->isVoidType()) | |||
2438 | return true; | |||
2439 | ||||
2440 | CheckedTemporaries CheckedTemps; | |||
2441 | return CheckEvaluationResult(CheckEvaluationResultKind::ConstantExpression, | |||
2442 | Info, DiagLoc, Type, Value, Kind, | |||
2443 | SourceLocation(), CheckedTemps); | |||
2444 | } | |||
2445 | ||||
2446 | /// Check that this evaluated value is fully-initialized and can be loaded by | |||
2447 | /// an lvalue-to-rvalue conversion. | |||
2448 | static bool CheckFullyInitialized(EvalInfo &Info, SourceLocation DiagLoc, | |||
2449 | QualType Type, const APValue &Value) { | |||
2450 | CheckedTemporaries CheckedTemps; | |||
2451 | return CheckEvaluationResult( | |||
2452 | CheckEvaluationResultKind::FullyInitialized, Info, DiagLoc, Type, Value, | |||
2453 | ConstantExprKind::Normal, SourceLocation(), CheckedTemps); | |||
2454 | } | |||
2455 | ||||
2456 | /// Enforce C++2a [expr.const]/4.17, which disallows new-expressions unless | |||
2457 | /// "the allocated storage is deallocated within the evaluation". | |||
2458 | static bool CheckMemoryLeaks(EvalInfo &Info) { | |||
2459 | if (!Info.HeapAllocs.empty()) { | |||
2460 | // We can still fold to a constant despite a compile-time memory leak, | |||
2461 | // so long as the heap allocation isn't referenced in the result (we check | |||
2462 | // that in CheckConstantExpression). | |||
2463 | Info.CCEDiag(Info.HeapAllocs.begin()->second.AllocExpr, | |||
2464 | diag::note_constexpr_memory_leak) | |||
2465 | << unsigned(Info.HeapAllocs.size() - 1); | |||
2466 | } | |||
2467 | return true; | |||
2468 | } | |||
2469 | ||||
2470 | static bool EvalPointerValueAsBool(const APValue &Value, bool &Result) { | |||
2471 | // A null base expression indicates a null pointer. These are always | |||
2472 | // evaluatable, and they are false unless the offset is zero. | |||
2473 | if (!Value.getLValueBase()) { | |||
2474 | // TODO: Should a non-null pointer with an offset of zero evaluate to true? | |||
2475 | Result = !Value.getLValueOffset().isZero(); | |||
2476 | return true; | |||
2477 | } | |||
2478 | ||||
2479 | // We have a non-null base. These are generally known to be true, but if it's | |||
2480 | // a weak declaration it can be null at runtime. | |||
2481 | Result = true; | |||
2482 | const ValueDecl *Decl = Value.getLValueBase().dyn_cast<const ValueDecl*>(); | |||
2483 | return !Decl || !Decl->isWeak(); | |||
2484 | } | |||
2485 | ||||
2486 | static bool HandleConversionToBool(const APValue &Val, bool &Result) { | |||
2487 | // TODO: This function should produce notes if it fails. | |||
2488 | switch (Val.getKind()) { | |||
2489 | case APValue::None: | |||
2490 | case APValue::Indeterminate: | |||
2491 | return false; | |||
2492 | case APValue::Int: | |||
2493 | Result = Val.getInt().getBoolValue(); | |||
2494 | return true; | |||
2495 | case APValue::FixedPoint: | |||
2496 | Result = Val.getFixedPoint().getBoolValue(); | |||
2497 | return true; | |||
2498 | case APValue::Float: | |||
2499 | Result = !Val.getFloat().isZero(); | |||
2500 | return true; | |||
2501 | case APValue::ComplexInt: | |||
2502 | Result = Val.getComplexIntReal().getBoolValue() || | |||
2503 | Val.getComplexIntImag().getBoolValue(); | |||
2504 | return true; | |||
2505 | case APValue::ComplexFloat: | |||
2506 | Result = !Val.getComplexFloatReal().isZero() || | |||
2507 | !Val.getComplexFloatImag().isZero(); | |||
2508 | return true; | |||
2509 | case APValue::LValue: | |||
2510 | return EvalPointerValueAsBool(Val, Result); | |||
2511 | case APValue::MemberPointer: | |||
2512 | if (Val.getMemberPointerDecl() && Val.getMemberPointerDecl()->isWeak()) { | |||
2513 | return false; | |||
2514 | } | |||
2515 | Result = Val.getMemberPointerDecl(); | |||
2516 | return true; | |||
2517 | case APValue::Vector: | |||
2518 | case APValue::Array: | |||
2519 | case APValue::Struct: | |||
2520 | case APValue::Union: | |||
2521 | case APValue::AddrLabelDiff: | |||
2522 | return false; | |||
2523 | } | |||
2524 | ||||
2525 | llvm_unreachable("unknown APValue kind")::llvm::llvm_unreachable_internal("unknown APValue kind", "clang/lib/AST/ExprConstant.cpp" , 2525); | |||
2526 | } | |||
2527 | ||||
2528 | static bool EvaluateAsBooleanCondition(const Expr *E, bool &Result, | |||
2529 | EvalInfo &Info) { | |||
2530 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 2530, __extension__ __PRETTY_FUNCTION__)); | |||
2531 | assert(E->isPRValue() && "missing lvalue-to-rvalue conv in bool condition")(static_cast <bool> (E->isPRValue() && "missing lvalue-to-rvalue conv in bool condition" ) ? void (0) : __assert_fail ("E->isPRValue() && \"missing lvalue-to-rvalue conv in bool condition\"" , "clang/lib/AST/ExprConstant.cpp", 2531, __extension__ __PRETTY_FUNCTION__ )); | |||
2532 | APValue Val; | |||
2533 | if (!Evaluate(Val, Info, E)) | |||
2534 | return false; | |||
2535 | return HandleConversionToBool(Val, Result); | |||
2536 | } | |||
2537 | ||||
2538 | template<typename T> | |||
2539 | static bool HandleOverflow(EvalInfo &Info, const Expr *E, | |||
2540 | const T &SrcValue, QualType DestType) { | |||
2541 | Info.CCEDiag(E, diag::note_constexpr_overflow) | |||
2542 | << SrcValue << DestType; | |||
2543 | return Info.noteUndefinedBehavior(); | |||
2544 | } | |||
2545 | ||||
2546 | static bool HandleFloatToIntCast(EvalInfo &Info, const Expr *E, | |||
2547 | QualType SrcType, const APFloat &Value, | |||
2548 | QualType DestType, APSInt &Result) { | |||
2549 | unsigned DestWidth = Info.Ctx.getIntWidth(DestType); | |||
2550 | // Determine whether we are converting to unsigned or signed. | |||
2551 | bool DestSigned = DestType->isSignedIntegerOrEnumerationType(); | |||
2552 | ||||
2553 | Result = APSInt(DestWidth, !DestSigned); | |||
2554 | bool ignored; | |||
2555 | if (Value.convertToInteger(Result, llvm::APFloat::rmTowardZero, &ignored) | |||
2556 | & APFloat::opInvalidOp) | |||
2557 | return HandleOverflow(Info, E, Value, DestType); | |||
2558 | return true; | |||
2559 | } | |||
2560 | ||||
2561 | /// Get rounding mode to use in evaluation of the specified expression. | |||
2562 | /// | |||
2563 | /// If rounding mode is unknown at compile time, still try to evaluate the | |||
2564 | /// expression. If the result is exact, it does not depend on rounding mode. | |||
2565 | /// So return "tonearest" mode instead of "dynamic". | |||
2566 | static llvm::RoundingMode getActiveRoundingMode(EvalInfo &Info, const Expr *E) { | |||
2567 | llvm::RoundingMode RM = | |||
2568 | E->getFPFeaturesInEffect(Info.Ctx.getLangOpts()).getRoundingMode(); | |||
2569 | if (RM == llvm::RoundingMode::Dynamic) | |||
2570 | RM = llvm::RoundingMode::NearestTiesToEven; | |||
2571 | return RM; | |||
2572 | } | |||
2573 | ||||
2574 | /// Check if the given evaluation result is allowed for constant evaluation. | |||
2575 | static bool checkFloatingPointResult(EvalInfo &Info, const Expr *E, | |||
2576 | APFloat::opStatus St) { | |||
2577 | // In a constant context, assume that any dynamic rounding mode or FP | |||
2578 | // exception state matches the default floating-point environment. | |||
2579 | if (Info.InConstantContext) | |||
2580 | return true; | |||
2581 | ||||
2582 | FPOptions FPO = E->getFPFeaturesInEffect(Info.Ctx.getLangOpts()); | |||
2583 | if ((St & APFloat::opInexact) && | |||
2584 | FPO.getRoundingMode() == llvm::RoundingMode::Dynamic) { | |||
2585 | // Inexact result means that it depends on rounding mode. If the requested | |||
2586 | // mode is dynamic, the evaluation cannot be made in compile time. | |||
2587 | Info.FFDiag(E, diag::note_constexpr_dynamic_rounding); | |||
2588 | return false; | |||
2589 | } | |||
2590 | ||||
2591 | if ((St != APFloat::opOK) && | |||
2592 | (FPO.getRoundingMode() == llvm::RoundingMode::Dynamic || | |||
2593 | FPO.getExceptionMode() != LangOptions::FPE_Ignore || | |||
2594 | FPO.getAllowFEnvAccess())) { | |||
2595 | Info.FFDiag(E, diag::note_constexpr_float_arithmetic_strict); | |||
2596 | return false; | |||
2597 | } | |||
2598 | ||||
2599 | if ((St & APFloat::opStatus::opInvalidOp) && | |||
2600 | FPO.getExceptionMode() != LangOptions::FPE_Ignore) { | |||
2601 | // There is no usefully definable result. | |||
2602 | Info.FFDiag(E); | |||
2603 | return false; | |||
2604 | } | |||
2605 | ||||
2606 | // FIXME: if: | |||
2607 | // - evaluation triggered other FP exception, and | |||
2608 | // - exception mode is not "ignore", and | |||
2609 | // - the expression being evaluated is not a part of global variable | |||
2610 | // initializer, | |||
2611 | // the evaluation probably need to be rejected. | |||
2612 | return true; | |||
2613 | } | |||
2614 | ||||
2615 | static bool HandleFloatToFloatCast(EvalInfo &Info, const Expr *E, | |||
2616 | QualType SrcType, QualType DestType, | |||
2617 | APFloat &Result) { | |||
2618 | assert(isa<CastExpr>(E) || isa<CompoundAssignOperator>(E))(static_cast <bool> (isa<CastExpr>(E) || isa<CompoundAssignOperator >(E)) ? void (0) : __assert_fail ("isa<CastExpr>(E) || isa<CompoundAssignOperator>(E)" , "clang/lib/AST/ExprConstant.cpp", 2618, __extension__ __PRETTY_FUNCTION__ )); | |||
2619 | llvm::RoundingMode RM = getActiveRoundingMode(Info, E); | |||
2620 | APFloat::opStatus St; | |||
2621 | APFloat Value = Result; | |||
2622 | bool ignored; | |||
2623 | St = Result.convert(Info.Ctx.getFloatTypeSemantics(DestType), RM, &ignored); | |||
2624 | return checkFloatingPointResult(Info, E, St); | |||
2625 | } | |||
2626 | ||||
2627 | static APSInt HandleIntToIntCast(EvalInfo &Info, const Expr *E, | |||
2628 | QualType DestType, QualType SrcType, | |||
2629 | const APSInt &Value) { | |||
2630 | unsigned DestWidth = Info.Ctx.getIntWidth(DestType); | |||
2631 | // Figure out if this is a truncate, extend or noop cast. | |||
2632 | // If the input is signed, do a sign extend, noop, or truncate. | |||
2633 | APSInt Result = Value.extOrTrunc(DestWidth); | |||
2634 | Result.setIsUnsigned(DestType->isUnsignedIntegerOrEnumerationType()); | |||
2635 | if (DestType->isBooleanType()) | |||
2636 | Result = Value.getBoolValue(); | |||
2637 | return Result; | |||
2638 | } | |||
2639 | ||||
2640 | static bool HandleIntToFloatCast(EvalInfo &Info, const Expr *E, | |||
2641 | const FPOptions FPO, | |||
2642 | QualType SrcType, const APSInt &Value, | |||
2643 | QualType DestType, APFloat &Result) { | |||
2644 | Result = APFloat(Info.Ctx.getFloatTypeSemantics(DestType), 1); | |||
2645 | llvm::RoundingMode RM = getActiveRoundingMode(Info, E); | |||
2646 | APFloat::opStatus St = Result.convertFromAPInt(Value, Value.isSigned(), RM); | |||
2647 | return checkFloatingPointResult(Info, E, St); | |||
2648 | } | |||
2649 | ||||
2650 | static bool truncateBitfieldValue(EvalInfo &Info, const Expr *E, | |||
2651 | APValue &Value, const FieldDecl *FD) { | |||
2652 | assert(FD->isBitField() && "truncateBitfieldValue on non-bitfield")(static_cast <bool> (FD->isBitField() && "truncateBitfieldValue on non-bitfield" ) ? void (0) : __assert_fail ("FD->isBitField() && \"truncateBitfieldValue on non-bitfield\"" , "clang/lib/AST/ExprConstant.cpp", 2652, __extension__ __PRETTY_FUNCTION__ )); | |||
2653 | ||||
2654 | if (!Value.isInt()) { | |||
2655 | // Trying to store a pointer-cast-to-integer into a bitfield. | |||
2656 | // FIXME: In this case, we should provide the diagnostic for casting | |||
2657 | // a pointer to an integer. | |||
2658 | assert(Value.isLValue() && "integral value neither int nor lvalue?")(static_cast <bool> (Value.isLValue() && "integral value neither int nor lvalue?" ) ? void (0) : __assert_fail ("Value.isLValue() && \"integral value neither int nor lvalue?\"" , "clang/lib/AST/ExprConstant.cpp", 2658, __extension__ __PRETTY_FUNCTION__ )); | |||
2659 | Info.FFDiag(E); | |||
2660 | return false; | |||
2661 | } | |||
2662 | ||||
2663 | APSInt &Int = Value.getInt(); | |||
2664 | unsigned OldBitWidth = Int.getBitWidth(); | |||
2665 | unsigned NewBitWidth = FD->getBitWidthValue(Info.Ctx); | |||
2666 | if (NewBitWidth < OldBitWidth) | |||
2667 | Int = Int.trunc(NewBitWidth).extend(OldBitWidth); | |||
2668 | return true; | |||
2669 | } | |||
2670 | ||||
2671 | static bool EvalAndBitcastToAPInt(EvalInfo &Info, const Expr *E, | |||
2672 | llvm::APInt &Res) { | |||
2673 | APValue SVal; | |||
2674 | if (!Evaluate(SVal, Info, E)) | |||
2675 | return false; | |||
2676 | if (SVal.isInt()) { | |||
2677 | Res = SVal.getInt(); | |||
2678 | return true; | |||
2679 | } | |||
2680 | if (SVal.isFloat()) { | |||
2681 | Res = SVal.getFloat().bitcastToAPInt(); | |||
2682 | return true; | |||
2683 | } | |||
2684 | if (SVal.isVector()) { | |||
2685 | QualType VecTy = E->getType(); | |||
2686 | unsigned VecSize = Info.Ctx.getTypeSize(VecTy); | |||
2687 | QualType EltTy = VecTy->castAs<VectorType>()->getElementType(); | |||
2688 | unsigned EltSize = Info.Ctx.getTypeSize(EltTy); | |||
2689 | bool BigEndian = Info.Ctx.getTargetInfo().isBigEndian(); | |||
2690 | Res = llvm::APInt::getZero(VecSize); | |||
2691 | for (unsigned i = 0; i < SVal.getVectorLength(); i++) { | |||
2692 | APValue &Elt = SVal.getVectorElt(i); | |||
2693 | llvm::APInt EltAsInt; | |||
2694 | if (Elt.isInt()) { | |||
2695 | EltAsInt = Elt.getInt(); | |||
2696 | } else if (Elt.isFloat()) { | |||
2697 | EltAsInt = Elt.getFloat().bitcastToAPInt(); | |||
2698 | } else { | |||
2699 | // Don't try to handle vectors of anything other than int or float | |||
2700 | // (not sure if it's possible to hit this case). | |||
2701 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
2702 | return false; | |||
2703 | } | |||
2704 | unsigned BaseEltSize = EltAsInt.getBitWidth(); | |||
2705 | if (BigEndian) | |||
2706 | Res |= EltAsInt.zextOrTrunc(VecSize).rotr(i*EltSize+BaseEltSize); | |||
2707 | else | |||
2708 | Res |= EltAsInt.zextOrTrunc(VecSize).rotl(i*EltSize); | |||
2709 | } | |||
2710 | return true; | |||
2711 | } | |||
2712 | // Give up if the input isn't an int, float, or vector. For example, we | |||
2713 | // reject "(v4i16)(intptr_t)&a". | |||
2714 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
2715 | return false; | |||
2716 | } | |||
2717 | ||||
2718 | /// Perform the given integer operation, which is known to need at most BitWidth | |||
2719 | /// bits, and check for overflow in the original type (if that type was not an | |||
2720 | /// unsigned type). | |||
2721 | template<typename Operation> | |||
2722 | static bool CheckedIntArithmetic(EvalInfo &Info, const Expr *E, | |||
2723 | const APSInt &LHS, const APSInt &RHS, | |||
2724 | unsigned BitWidth, Operation Op, | |||
2725 | APSInt &Result) { | |||
2726 | if (LHS.isUnsigned()) { | |||
2727 | Result = Op(LHS, RHS); | |||
2728 | return true; | |||
2729 | } | |||
2730 | ||||
2731 | APSInt Value(Op(LHS.extend(BitWidth), RHS.extend(BitWidth)), false); | |||
2732 | Result = Value.trunc(LHS.getBitWidth()); | |||
2733 | if (Result.extend(BitWidth) != Value) { | |||
2734 | if (Info.checkingForUndefinedBehavior()) | |||
2735 | Info.Ctx.getDiagnostics().Report(E->getExprLoc(), | |||
2736 | diag::warn_integer_constant_overflow) | |||
2737 | << toString(Result, 10) << E->getType(); | |||
2738 | return HandleOverflow(Info, E, Value, E->getType()); | |||
2739 | } | |||
2740 | return true; | |||
2741 | } | |||
2742 | ||||
2743 | /// Perform the given binary integer operation. | |||
2744 | static bool handleIntIntBinOp(EvalInfo &Info, const Expr *E, const APSInt &LHS, | |||
2745 | BinaryOperatorKind Opcode, APSInt RHS, | |||
2746 | APSInt &Result) { | |||
2747 | bool HandleOverflowResult = true; | |||
2748 | switch (Opcode) { | |||
2749 | default: | |||
2750 | Info.FFDiag(E); | |||
2751 | return false; | |||
2752 | case BO_Mul: | |||
2753 | return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() * 2, | |||
2754 | std::multiplies<APSInt>(), Result); | |||
2755 | case BO_Add: | |||
2756 | return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() + 1, | |||
2757 | std::plus<APSInt>(), Result); | |||
2758 | case BO_Sub: | |||
2759 | return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() + 1, | |||
2760 | std::minus<APSInt>(), Result); | |||
2761 | case BO_And: Result = LHS & RHS; return true; | |||
2762 | case BO_Xor: Result = LHS ^ RHS; return true; | |||
2763 | case BO_Or: Result = LHS | RHS; return true; | |||
2764 | case BO_Div: | |||
2765 | case BO_Rem: | |||
2766 | if (RHS == 0) { | |||
2767 | Info.FFDiag(E, diag::note_expr_divide_by_zero); | |||
2768 | return false; | |||
2769 | } | |||
2770 | // Check for overflow case: INT_MIN / -1 or INT_MIN % -1. APSInt supports | |||
2771 | // this operation and gives the two's complement result. | |||
2772 | if (RHS.isNegative() && RHS.isAllOnes() && LHS.isSigned() && | |||
2773 | LHS.isMinSignedValue()) | |||
2774 | HandleOverflowResult = HandleOverflow( | |||
2775 | Info, E, -LHS.extend(LHS.getBitWidth() + 1), E->getType()); | |||
2776 | Result = (Opcode == BO_Rem ? LHS % RHS : LHS / RHS); | |||
2777 | return HandleOverflowResult; | |||
2778 | case BO_Shl: { | |||
2779 | if (Info.getLangOpts().OpenCL) | |||
2780 | // OpenCL 6.3j: shift values are effectively % word size of LHS. | |||
2781 | RHS &= APSInt(llvm::APInt(RHS.getBitWidth(), | |||
2782 | static_cast<uint64_t>(LHS.getBitWidth() - 1)), | |||
2783 | RHS.isUnsigned()); | |||
2784 | else if (RHS.isSigned() && RHS.isNegative()) { | |||
2785 | // During constant-folding, a negative shift is an opposite shift. Such | |||
2786 | // a shift is not a constant expression. | |||
2787 | Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHS; | |||
2788 | RHS = -RHS; | |||
2789 | goto shift_right; | |||
2790 | } | |||
2791 | shift_left: | |||
2792 | // C++11 [expr.shift]p1: Shift width must be less than the bit width of | |||
2793 | // the shifted type. | |||
2794 | unsigned SA = (unsigned) RHS.getLimitedValue(LHS.getBitWidth()-1); | |||
2795 | if (SA != RHS) { | |||
2796 | Info.CCEDiag(E, diag::note_constexpr_large_shift) | |||
2797 | << RHS << E->getType() << LHS.getBitWidth(); | |||
2798 | } else if (LHS.isSigned() && !Info.getLangOpts().CPlusPlus20) { | |||
2799 | // C++11 [expr.shift]p2: A signed left shift must have a non-negative | |||
2800 | // operand, and must not overflow the corresponding unsigned type. | |||
2801 | // C++2a [expr.shift]p2: E1 << E2 is the unique value congruent to | |||
2802 | // E1 x 2^E2 module 2^N. | |||
2803 | if (LHS.isNegative()) | |||
2804 | Info.CCEDiag(E, diag::note_constexpr_lshift_of_negative) << LHS; | |||
2805 | else if (LHS.countl_zero() < SA) | |||
2806 | Info.CCEDiag(E, diag::note_constexpr_lshift_discards); | |||
2807 | } | |||
2808 | Result = LHS << SA; | |||
2809 | return true; | |||
2810 | } | |||
2811 | case BO_Shr: { | |||
2812 | if (Info.getLangOpts().OpenCL) | |||
2813 | // OpenCL 6.3j: shift values are effectively % word size of LHS. | |||
2814 | RHS &= APSInt(llvm::APInt(RHS.getBitWidth(), | |||
2815 | static_cast<uint64_t>(LHS.getBitWidth() - 1)), | |||
2816 | RHS.isUnsigned()); | |||
2817 | else if (RHS.isSigned() && RHS.isNegative()) { | |||
2818 | // During constant-folding, a negative shift is an opposite shift. Such a | |||
2819 | // shift is not a constant expression. | |||
2820 | Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHS; | |||
2821 | RHS = -RHS; | |||
2822 | goto shift_left; | |||
2823 | } | |||
2824 | shift_right: | |||
2825 | // C++11 [expr.shift]p1: Shift width must be less than the bit width of the | |||
2826 | // shifted type. | |||
2827 | unsigned SA = (unsigned) RHS.getLimitedValue(LHS.getBitWidth()-1); | |||
2828 | if (SA != RHS) | |||
2829 | Info.CCEDiag(E, diag::note_constexpr_large_shift) | |||
2830 | << RHS << E->getType() << LHS.getBitWidth(); | |||
2831 | Result = LHS >> SA; | |||
2832 | return true; | |||
2833 | } | |||
2834 | ||||
2835 | case BO_LT: Result = LHS < RHS; return true; | |||
2836 | case BO_GT: Result = LHS > RHS; return true; | |||
2837 | case BO_LE: Result = LHS <= RHS; return true; | |||
2838 | case BO_GE: Result = LHS >= RHS; return true; | |||
2839 | case BO_EQ: Result = LHS == RHS; return true; | |||
2840 | case BO_NE: Result = LHS != RHS; return true; | |||
2841 | case BO_Cmp: | |||
2842 | llvm_unreachable("BO_Cmp should be handled elsewhere")::llvm::llvm_unreachable_internal("BO_Cmp should be handled elsewhere" , "clang/lib/AST/ExprConstant.cpp", 2842); | |||
2843 | } | |||
2844 | } | |||
2845 | ||||
2846 | /// Perform the given binary floating-point operation, in-place, on LHS. | |||
2847 | static bool handleFloatFloatBinOp(EvalInfo &Info, const BinaryOperator *E, | |||
2848 | APFloat &LHS, BinaryOperatorKind Opcode, | |||
2849 | const APFloat &RHS) { | |||
2850 | llvm::RoundingMode RM = getActiveRoundingMode(Info, E); | |||
2851 | APFloat::opStatus St; | |||
2852 | switch (Opcode) { | |||
2853 | default: | |||
2854 | Info.FFDiag(E); | |||
2855 | return false; | |||
2856 | case BO_Mul: | |||
2857 | St = LHS.multiply(RHS, RM); | |||
2858 | break; | |||
2859 | case BO_Add: | |||
2860 | St = LHS.add(RHS, RM); | |||
2861 | break; | |||
2862 | case BO_Sub: | |||
2863 | St = LHS.subtract(RHS, RM); | |||
2864 | break; | |||
2865 | case BO_Div: | |||
2866 | // [expr.mul]p4: | |||
2867 | // If the second operand of / or % is zero the behavior is undefined. | |||
2868 | if (RHS.isZero()) | |||
2869 | Info.CCEDiag(E, diag::note_expr_divide_by_zero); | |||
2870 | St = LHS.divide(RHS, RM); | |||
2871 | break; | |||
2872 | } | |||
2873 | ||||
2874 | // [expr.pre]p4: | |||
2875 | // If during the evaluation of an expression, the result is not | |||
2876 | // mathematically defined [...], the behavior is undefined. | |||
2877 | // FIXME: C++ rules require us to not conform to IEEE 754 here. | |||
2878 | if (LHS.isNaN()) { | |||
2879 | Info.CCEDiag(E, diag::note_constexpr_float_arithmetic) << LHS.isNaN(); | |||
2880 | return Info.noteUndefinedBehavior(); | |||
2881 | } | |||
2882 | ||||
2883 | return checkFloatingPointResult(Info, E, St); | |||
2884 | } | |||
2885 | ||||
2886 | static bool handleLogicalOpForVector(const APInt &LHSValue, | |||
2887 | BinaryOperatorKind Opcode, | |||
2888 | const APInt &RHSValue, APInt &Result) { | |||
2889 | bool LHS = (LHSValue != 0); | |||
2890 | bool RHS = (RHSValue != 0); | |||
2891 | ||||
2892 | if (Opcode == BO_LAnd) | |||
2893 | Result = LHS && RHS; | |||
2894 | else | |||
2895 | Result = LHS || RHS; | |||
2896 | return true; | |||
2897 | } | |||
2898 | static bool handleLogicalOpForVector(const APFloat &LHSValue, | |||
2899 | BinaryOperatorKind Opcode, | |||
2900 | const APFloat &RHSValue, APInt &Result) { | |||
2901 | bool LHS = !LHSValue.isZero(); | |||
2902 | bool RHS = !RHSValue.isZero(); | |||
2903 | ||||
2904 | if (Opcode == BO_LAnd) | |||
2905 | Result = LHS && RHS; | |||
2906 | else | |||
2907 | Result = LHS || RHS; | |||
2908 | return true; | |||
2909 | } | |||
2910 | ||||
2911 | static bool handleLogicalOpForVector(const APValue &LHSValue, | |||
2912 | BinaryOperatorKind Opcode, | |||
2913 | const APValue &RHSValue, APInt &Result) { | |||
2914 | // The result is always an int type, however operands match the first. | |||
2915 | if (LHSValue.getKind() == APValue::Int) | |||
2916 | return handleLogicalOpForVector(LHSValue.getInt(), Opcode, | |||
2917 | RHSValue.getInt(), Result); | |||
2918 | assert(LHSValue.getKind() == APValue::Float && "Should be no other options")(static_cast <bool> (LHSValue.getKind() == APValue::Float && "Should be no other options") ? void (0) : __assert_fail ("LHSValue.getKind() == APValue::Float && \"Should be no other options\"" , "clang/lib/AST/ExprConstant.cpp", 2918, __extension__ __PRETTY_FUNCTION__ )); | |||
2919 | return handleLogicalOpForVector(LHSValue.getFloat(), Opcode, | |||
2920 | RHSValue.getFloat(), Result); | |||
2921 | } | |||
2922 | ||||
2923 | template <typename APTy> | |||
2924 | static bool | |||
2925 | handleCompareOpForVectorHelper(const APTy &LHSValue, BinaryOperatorKind Opcode, | |||
2926 | const APTy &RHSValue, APInt &Result) { | |||
2927 | switch (Opcode) { | |||
2928 | default: | |||
2929 | llvm_unreachable("unsupported binary operator")::llvm::llvm_unreachable_internal("unsupported binary operator" , "clang/lib/AST/ExprConstant.cpp", 2929); | |||
2930 | case BO_EQ: | |||
2931 | Result = (LHSValue == RHSValue); | |||
2932 | break; | |||
2933 | case BO_NE: | |||
2934 | Result = (LHSValue != RHSValue); | |||
2935 | break; | |||
2936 | case BO_LT: | |||
2937 | Result = (LHSValue < RHSValue); | |||
2938 | break; | |||
2939 | case BO_GT: | |||
2940 | Result = (LHSValue > RHSValue); | |||
2941 | break; | |||
2942 | case BO_LE: | |||
2943 | Result = (LHSValue <= RHSValue); | |||
2944 | break; | |||
2945 | case BO_GE: | |||
2946 | Result = (LHSValue >= RHSValue); | |||
2947 | break; | |||
2948 | } | |||
2949 | ||||
2950 | // The boolean operations on these vector types use an instruction that | |||
2951 | // results in a mask of '-1' for the 'truth' value. Ensure that we negate 1 | |||
2952 | // to -1 to make sure that we produce the correct value. | |||
2953 | Result.negate(); | |||
2954 | ||||
2955 | return true; | |||
2956 | } | |||
2957 | ||||
2958 | static bool handleCompareOpForVector(const APValue &LHSValue, | |||
2959 | BinaryOperatorKind Opcode, | |||
2960 | const APValue &RHSValue, APInt &Result) { | |||
2961 | // The result is always an int type, however operands match the first. | |||
2962 | if (LHSValue.getKind() == APValue::Int) | |||
2963 | return handleCompareOpForVectorHelper(LHSValue.getInt(), Opcode, | |||
2964 | RHSValue.getInt(), Result); | |||
2965 | assert(LHSValue.getKind() == APValue::Float && "Should be no other options")(static_cast <bool> (LHSValue.getKind() == APValue::Float && "Should be no other options") ? void (0) : __assert_fail ("LHSValue.getKind() == APValue::Float && \"Should be no other options\"" , "clang/lib/AST/ExprConstant.cpp", 2965, __extension__ __PRETTY_FUNCTION__ )); | |||
2966 | return handleCompareOpForVectorHelper(LHSValue.getFloat(), Opcode, | |||
2967 | RHSValue.getFloat(), Result); | |||
2968 | } | |||
2969 | ||||
2970 | // Perform binary operations for vector types, in place on the LHS. | |||
2971 | static bool handleVectorVectorBinOp(EvalInfo &Info, const BinaryOperator *E, | |||
2972 | BinaryOperatorKind Opcode, | |||
2973 | APValue &LHSValue, | |||
2974 | const APValue &RHSValue) { | |||
2975 | assert(Opcode != BO_PtrMemD && Opcode != BO_PtrMemI &&(static_cast <bool> (Opcode != BO_PtrMemD && Opcode != BO_PtrMemI && "Operation not supported on vector types" ) ? void (0) : __assert_fail ("Opcode != BO_PtrMemD && Opcode != BO_PtrMemI && \"Operation not supported on vector types\"" , "clang/lib/AST/ExprConstant.cpp", 2976, __extension__ __PRETTY_FUNCTION__ )) | |||
2976 | "Operation not supported on vector types")(static_cast <bool> (Opcode != BO_PtrMemD && Opcode != BO_PtrMemI && "Operation not supported on vector types" ) ? void (0) : __assert_fail ("Opcode != BO_PtrMemD && Opcode != BO_PtrMemI && \"Operation not supported on vector types\"" , "clang/lib/AST/ExprConstant.cpp", 2976, __extension__ __PRETTY_FUNCTION__ )); | |||
2977 | ||||
2978 | const auto *VT = E->getType()->castAs<VectorType>(); | |||
2979 | unsigned NumElements = VT->getNumElements(); | |||
2980 | QualType EltTy = VT->getElementType(); | |||
2981 | ||||
2982 | // In the cases (typically C as I've observed) where we aren't evaluating | |||
2983 | // constexpr but are checking for cases where the LHS isn't yet evaluatable, | |||
2984 | // just give up. | |||
2985 | if (!LHSValue.isVector()) { | |||
2986 | assert(LHSValue.isLValue() &&(static_cast <bool> (LHSValue.isLValue() && "A vector result that isn't a vector OR uncalculated LValue" ) ? void (0) : __assert_fail ("LHSValue.isLValue() && \"A vector result that isn't a vector OR uncalculated LValue\"" , "clang/lib/AST/ExprConstant.cpp", 2987, __extension__ __PRETTY_FUNCTION__ )) | |||
2987 | "A vector result that isn't a vector OR uncalculated LValue")(static_cast <bool> (LHSValue.isLValue() && "A vector result that isn't a vector OR uncalculated LValue" ) ? void (0) : __assert_fail ("LHSValue.isLValue() && \"A vector result that isn't a vector OR uncalculated LValue\"" , "clang/lib/AST/ExprConstant.cpp", 2987, __extension__ __PRETTY_FUNCTION__ )); | |||
2988 | Info.FFDiag(E); | |||
2989 | return false; | |||
2990 | } | |||
2991 | ||||
2992 | assert(LHSValue.getVectorLength() == NumElements &&(static_cast <bool> (LHSValue.getVectorLength() == NumElements && RHSValue.getVectorLength() == NumElements && "Different vector sizes") ? void (0) : __assert_fail ("LHSValue.getVectorLength() == NumElements && RHSValue.getVectorLength() == NumElements && \"Different vector sizes\"" , "clang/lib/AST/ExprConstant.cpp", 2993, __extension__ __PRETTY_FUNCTION__ )) | |||
2993 | RHSValue.getVectorLength() == NumElements && "Different vector sizes")(static_cast <bool> (LHSValue.getVectorLength() == NumElements && RHSValue.getVectorLength() == NumElements && "Different vector sizes") ? void (0) : __assert_fail ("LHSValue.getVectorLength() == NumElements && RHSValue.getVectorLength() == NumElements && \"Different vector sizes\"" , "clang/lib/AST/ExprConstant.cpp", 2993, __extension__ __PRETTY_FUNCTION__ )); | |||
2994 | ||||
2995 | SmallVector<APValue, 4> ResultElements; | |||
2996 | ||||
2997 | for (unsigned EltNum = 0; EltNum < NumElements; ++EltNum) { | |||
2998 | APValue LHSElt = LHSValue.getVectorElt(EltNum); | |||
2999 | APValue RHSElt = RHSValue.getVectorElt(EltNum); | |||
3000 | ||||
3001 | if (EltTy->isIntegerType()) { | |||
3002 | APSInt EltResult{Info.Ctx.getIntWidth(EltTy), | |||
3003 | EltTy->isUnsignedIntegerType()}; | |||
3004 | bool Success = true; | |||
3005 | ||||
3006 | if (BinaryOperator::isLogicalOp(Opcode)) | |||
3007 | Success = handleLogicalOpForVector(LHSElt, Opcode, RHSElt, EltResult); | |||
3008 | else if (BinaryOperator::isComparisonOp(Opcode)) | |||
3009 | Success = handleCompareOpForVector(LHSElt, Opcode, RHSElt, EltResult); | |||
3010 | else | |||
3011 | Success = handleIntIntBinOp(Info, E, LHSElt.getInt(), Opcode, | |||
3012 | RHSElt.getInt(), EltResult); | |||
3013 | ||||
3014 | if (!Success) { | |||
3015 | Info.FFDiag(E); | |||
3016 | return false; | |||
3017 | } | |||
3018 | ResultElements.emplace_back(EltResult); | |||
3019 | ||||
3020 | } else if (EltTy->isFloatingType()) { | |||
3021 | assert(LHSElt.getKind() == APValue::Float &&(static_cast <bool> (LHSElt.getKind() == APValue::Float && RHSElt.getKind() == APValue::Float && "Mismatched LHS/RHS/Result Type" ) ? void (0) : __assert_fail ("LHSElt.getKind() == APValue::Float && RHSElt.getKind() == APValue::Float && \"Mismatched LHS/RHS/Result Type\"" , "clang/lib/AST/ExprConstant.cpp", 3023, __extension__ __PRETTY_FUNCTION__ )) | |||
3022 | RHSElt.getKind() == APValue::Float &&(static_cast <bool> (LHSElt.getKind() == APValue::Float && RHSElt.getKind() == APValue::Float && "Mismatched LHS/RHS/Result Type" ) ? void (0) : __assert_fail ("LHSElt.getKind() == APValue::Float && RHSElt.getKind() == APValue::Float && \"Mismatched LHS/RHS/Result Type\"" , "clang/lib/AST/ExprConstant.cpp", 3023, __extension__ __PRETTY_FUNCTION__ )) | |||
3023 | "Mismatched LHS/RHS/Result Type")(static_cast <bool> (LHSElt.getKind() == APValue::Float && RHSElt.getKind() == APValue::Float && "Mismatched LHS/RHS/Result Type" ) ? void (0) : __assert_fail ("LHSElt.getKind() == APValue::Float && RHSElt.getKind() == APValue::Float && \"Mismatched LHS/RHS/Result Type\"" , "clang/lib/AST/ExprConstant.cpp", 3023, __extension__ __PRETTY_FUNCTION__ )); | |||
3024 | APFloat LHSFloat = LHSElt.getFloat(); | |||
3025 | ||||
3026 | if (!handleFloatFloatBinOp(Info, E, LHSFloat, Opcode, | |||
3027 | RHSElt.getFloat())) { | |||
3028 | Info.FFDiag(E); | |||
3029 | return false; | |||
3030 | } | |||
3031 | ||||
3032 | ResultElements.emplace_back(LHSFloat); | |||
3033 | } | |||
3034 | } | |||
3035 | ||||
3036 | LHSValue = APValue(ResultElements.data(), ResultElements.size()); | |||
3037 | return true; | |||
3038 | } | |||
3039 | ||||
3040 | /// Cast an lvalue referring to a base subobject to a derived class, by | |||
3041 | /// truncating the lvalue's path to the given length. | |||
3042 | static bool CastToDerivedClass(EvalInfo &Info, const Expr *E, LValue &Result, | |||
3043 | const RecordDecl *TruncatedType, | |||
3044 | unsigned TruncatedElements) { | |||
3045 | SubobjectDesignator &D = Result.Designator; | |||
3046 | ||||
3047 | // Check we actually point to a derived class object. | |||
3048 | if (TruncatedElements == D.Entries.size()) | |||
3049 | return true; | |||
3050 | assert(TruncatedElements >= D.MostDerivedPathLength &&(static_cast <bool> (TruncatedElements >= D.MostDerivedPathLength && "not casting to a derived class") ? void (0) : __assert_fail ("TruncatedElements >= D.MostDerivedPathLength && \"not casting to a derived class\"" , "clang/lib/AST/ExprConstant.cpp", 3051, __extension__ __PRETTY_FUNCTION__ )) | |||
3051 | "not casting to a derived class")(static_cast <bool> (TruncatedElements >= D.MostDerivedPathLength && "not casting to a derived class") ? void (0) : __assert_fail ("TruncatedElements >= D.MostDerivedPathLength && \"not casting to a derived class\"" , "clang/lib/AST/ExprConstant.cpp", 3051, __extension__ __PRETTY_FUNCTION__ )); | |||
3052 | if (!Result.checkSubobject(Info, E, CSK_Derived)) | |||
3053 | return false; | |||
3054 | ||||
3055 | // Truncate the path to the subobject, and remove any derived-to-base offsets. | |||
3056 | const RecordDecl *RD = TruncatedType; | |||
3057 | for (unsigned I = TruncatedElements, N = D.Entries.size(); I != N; ++I) { | |||
3058 | if (RD->isInvalidDecl()) return false; | |||
3059 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
3060 | const CXXRecordDecl *Base = getAsBaseClass(D.Entries[I]); | |||
3061 | if (isVirtualBaseClass(D.Entries[I])) | |||
3062 | Result.Offset -= Layout.getVBaseClassOffset(Base); | |||
3063 | else | |||
3064 | Result.Offset -= Layout.getBaseClassOffset(Base); | |||
3065 | RD = Base; | |||
3066 | } | |||
3067 | D.Entries.resize(TruncatedElements); | |||
3068 | return true; | |||
3069 | } | |||
3070 | ||||
3071 | static bool HandleLValueDirectBase(EvalInfo &Info, const Expr *E, LValue &Obj, | |||
3072 | const CXXRecordDecl *Derived, | |||
3073 | const CXXRecordDecl *Base, | |||
3074 | const ASTRecordLayout *RL = nullptr) { | |||
3075 | if (!RL) { | |||
3076 | if (Derived->isInvalidDecl()) return false; | |||
3077 | RL = &Info.Ctx.getASTRecordLayout(Derived); | |||
3078 | } | |||
3079 | ||||
3080 | Obj.getLValueOffset() += RL->getBaseClassOffset(Base); | |||
3081 | Obj.addDecl(Info, E, Base, /*Virtual*/ false); | |||
3082 | return true; | |||
3083 | } | |||
3084 | ||||
3085 | static bool HandleLValueBase(EvalInfo &Info, const Expr *E, LValue &Obj, | |||
3086 | const CXXRecordDecl *DerivedDecl, | |||
3087 | const CXXBaseSpecifier *Base) { | |||
3088 | const CXXRecordDecl *BaseDecl = Base->getType()->getAsCXXRecordDecl(); | |||
3089 | ||||
3090 | if (!Base->isVirtual()) | |||
3091 | return HandleLValueDirectBase(Info, E, Obj, DerivedDecl, BaseDecl); | |||
3092 | ||||
3093 | SubobjectDesignator &D = Obj.Designator; | |||
3094 | if (D.Invalid) | |||
3095 | return false; | |||
3096 | ||||
3097 | // Extract most-derived object and corresponding type. | |||
3098 | DerivedDecl = D.MostDerivedType->getAsCXXRecordDecl(); | |||
3099 | if (!CastToDerivedClass(Info, E, Obj, DerivedDecl, D.MostDerivedPathLength)) | |||
3100 | return false; | |||
3101 | ||||
3102 | // Find the virtual base class. | |||
3103 | if (DerivedDecl->isInvalidDecl()) return false; | |||
3104 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(DerivedDecl); | |||
3105 | Obj.getLValueOffset() += Layout.getVBaseClassOffset(BaseDecl); | |||
3106 | Obj.addDecl(Info, E, BaseDecl, /*Virtual*/ true); | |||
3107 | return true; | |||
3108 | } | |||
3109 | ||||
3110 | static bool HandleLValueBasePath(EvalInfo &Info, const CastExpr *E, | |||
3111 | QualType Type, LValue &Result) { | |||
3112 | for (CastExpr::path_const_iterator PathI = E->path_begin(), | |||
3113 | PathE = E->path_end(); | |||
3114 | PathI != PathE; ++PathI) { | |||
3115 | if (!HandleLValueBase(Info, E, Result, Type->getAsCXXRecordDecl(), | |||
3116 | *PathI)) | |||
3117 | return false; | |||
3118 | Type = (*PathI)->getType(); | |||
3119 | } | |||
3120 | return true; | |||
3121 | } | |||
3122 | ||||
3123 | /// Cast an lvalue referring to a derived class to a known base subobject. | |||
3124 | static bool CastToBaseClass(EvalInfo &Info, const Expr *E, LValue &Result, | |||
3125 | const CXXRecordDecl *DerivedRD, | |||
3126 | const CXXRecordDecl *BaseRD) { | |||
3127 | CXXBasePaths Paths(/*FindAmbiguities=*/false, | |||
3128 | /*RecordPaths=*/true, /*DetectVirtual=*/false); | |||
3129 | if (!DerivedRD->isDerivedFrom(BaseRD, Paths)) | |||
3130 | llvm_unreachable("Class must be derived from the passed in base class!")::llvm::llvm_unreachable_internal("Class must be derived from the passed in base class!" , "clang/lib/AST/ExprConstant.cpp", 3130); | |||
3131 | ||||
3132 | for (CXXBasePathElement &Elem : Paths.front()) | |||
3133 | if (!HandleLValueBase(Info, E, Result, Elem.Class, Elem.Base)) | |||
3134 | return false; | |||
3135 | return true; | |||
3136 | } | |||
3137 | ||||
3138 | /// Update LVal to refer to the given field, which must be a member of the type | |||
3139 | /// currently described by LVal. | |||
3140 | static bool HandleLValueMember(EvalInfo &Info, const Expr *E, LValue &LVal, | |||
3141 | const FieldDecl *FD, | |||
3142 | const ASTRecordLayout *RL = nullptr) { | |||
3143 | if (!RL) { | |||
3144 | if (FD->getParent()->isInvalidDecl()) return false; | |||
3145 | RL = &Info.Ctx.getASTRecordLayout(FD->getParent()); | |||
3146 | } | |||
3147 | ||||
3148 | unsigned I = FD->getFieldIndex(); | |||
3149 | LVal.adjustOffset(Info.Ctx.toCharUnitsFromBits(RL->getFieldOffset(I))); | |||
3150 | LVal.addDecl(Info, E, FD); | |||
3151 | return true; | |||
3152 | } | |||
3153 | ||||
3154 | /// Update LVal to refer to the given indirect field. | |||
3155 | static bool HandleLValueIndirectMember(EvalInfo &Info, const Expr *E, | |||
3156 | LValue &LVal, | |||
3157 | const IndirectFieldDecl *IFD) { | |||
3158 | for (const auto *C : IFD->chain()) | |||
3159 | if (!HandleLValueMember(Info, E, LVal, cast<FieldDecl>(C))) | |||
3160 | return false; | |||
3161 | return true; | |||
3162 | } | |||
3163 | ||||
3164 | /// Get the size of the given type in char units. | |||
3165 | static bool HandleSizeof(EvalInfo &Info, SourceLocation Loc, | |||
3166 | QualType Type, CharUnits &Size) { | |||
3167 | // sizeof(void), __alignof__(void), sizeof(function) = 1 as a gcc | |||
3168 | // extension. | |||
3169 | if (Type->isVoidType() || Type->isFunctionType()) { | |||
3170 | Size = CharUnits::One(); | |||
3171 | return true; | |||
3172 | } | |||
3173 | ||||
3174 | if (Type->isDependentType()) { | |||
3175 | Info.FFDiag(Loc); | |||
3176 | return false; | |||
3177 | } | |||
3178 | ||||
3179 | if (!Type->isConstantSizeType()) { | |||
3180 | // sizeof(vla) is not a constantexpr: C99 6.5.3.4p2. | |||
3181 | // FIXME: Better diagnostic. | |||
3182 | Info.FFDiag(Loc); | |||
3183 | return false; | |||
3184 | } | |||
3185 | ||||
3186 | Size = Info.Ctx.getTypeSizeInChars(Type); | |||
3187 | return true; | |||
3188 | } | |||
3189 | ||||
3190 | /// Update a pointer value to model pointer arithmetic. | |||
3191 | /// \param Info - Information about the ongoing evaluation. | |||
3192 | /// \param E - The expression being evaluated, for diagnostic purposes. | |||
3193 | /// \param LVal - The pointer value to be updated. | |||
3194 | /// \param EltTy - The pointee type represented by LVal. | |||
3195 | /// \param Adjustment - The adjustment, in objects of type EltTy, to add. | |||
3196 | static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E, | |||
3197 | LValue &LVal, QualType EltTy, | |||
3198 | APSInt Adjustment) { | |||
3199 | CharUnits SizeOfPointee; | |||
3200 | if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfPointee)) | |||
3201 | return false; | |||
3202 | ||||
3203 | LVal.adjustOffsetAndIndex(Info, E, Adjustment, SizeOfPointee); | |||
3204 | return true; | |||
3205 | } | |||
3206 | ||||
3207 | static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E, | |||
3208 | LValue &LVal, QualType EltTy, | |||
3209 | int64_t Adjustment) { | |||
3210 | return HandleLValueArrayAdjustment(Info, E, LVal, EltTy, | |||
3211 | APSInt::get(Adjustment)); | |||
3212 | } | |||
3213 | ||||
3214 | /// Update an lvalue to refer to a component of a complex number. | |||
3215 | /// \param Info - Information about the ongoing evaluation. | |||
3216 | /// \param LVal - The lvalue to be updated. | |||
3217 | /// \param EltTy - The complex number's component type. | |||
3218 | /// \param Imag - False for the real component, true for the imaginary. | |||
3219 | static bool HandleLValueComplexElement(EvalInfo &Info, const Expr *E, | |||
3220 | LValue &LVal, QualType EltTy, | |||
3221 | bool Imag) { | |||
3222 | if (Imag) { | |||
3223 | CharUnits SizeOfComponent; | |||
3224 | if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfComponent)) | |||
3225 | return false; | |||
3226 | LVal.Offset += SizeOfComponent; | |||
3227 | } | |||
3228 | LVal.addComplex(Info, E, EltTy, Imag); | |||
3229 | return true; | |||
3230 | } | |||
3231 | ||||
3232 | /// Try to evaluate the initializer for a variable declaration. | |||
3233 | /// | |||
3234 | /// \param Info Information about the ongoing evaluation. | |||
3235 | /// \param E An expression to be used when printing diagnostics. | |||
3236 | /// \param VD The variable whose initializer should be obtained. | |||
3237 | /// \param Version The version of the variable within the frame. | |||
3238 | /// \param Frame The frame in which the variable was created. Must be null | |||
3239 | /// if this variable is not local to the evaluation. | |||
3240 | /// \param Result Filled in with a pointer to the value of the variable. | |||
3241 | static bool evaluateVarDeclInit(EvalInfo &Info, const Expr *E, | |||
3242 | const VarDecl *VD, CallStackFrame *Frame, | |||
3243 | unsigned Version, APValue *&Result) { | |||
3244 | APValue::LValueBase Base(VD, Frame ? Frame->Index : 0, Version); | |||
3245 | ||||
3246 | // If this is a local variable, dig out its value. | |||
3247 | if (Frame) { | |||
3248 | Result = Frame->getTemporary(VD, Version); | |||
3249 | if (Result) | |||
3250 | return true; | |||
3251 | ||||
3252 | if (!isa<ParmVarDecl>(VD)) { | |||
3253 | // Assume variables referenced within a lambda's call operator that were | |||
3254 | // not declared within the call operator are captures and during checking | |||
3255 | // of a potential constant expression, assume they are unknown constant | |||
3256 | // expressions. | |||
3257 | assert(isLambdaCallOperator(Frame->Callee) &&(static_cast <bool> (isLambdaCallOperator(Frame->Callee ) && (VD->getDeclContext() != Frame->Callee || VD ->isInitCapture()) && "missing value for local variable" ) ? void (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\"" , "clang/lib/AST/ExprConstant.cpp", 3259, __extension__ __PRETTY_FUNCTION__ )) | |||
3258 | (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) &&(static_cast <bool> (isLambdaCallOperator(Frame->Callee ) && (VD->getDeclContext() != Frame->Callee || VD ->isInitCapture()) && "missing value for local variable" ) ? void (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\"" , "clang/lib/AST/ExprConstant.cpp", 3259, __extension__ __PRETTY_FUNCTION__ )) | |||
3259 | "missing value for local variable")(static_cast <bool> (isLambdaCallOperator(Frame->Callee ) && (VD->getDeclContext() != Frame->Callee || VD ->isInitCapture()) && "missing value for local variable" ) ? void (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\"" , "clang/lib/AST/ExprConstant.cpp", 3259, __extension__ __PRETTY_FUNCTION__ )); | |||
3260 | if (Info.checkingPotentialConstantExpression()) | |||
3261 | return false; | |||
3262 | // FIXME: This diagnostic is bogus; we do support captures. Is this code | |||
3263 | // still reachable at all? | |||
3264 | Info.FFDiag(E->getBeginLoc(), | |||
3265 | diag::note_unimplemented_constexpr_lambda_feature_ast) | |||
3266 | << "captures not currently allowed"; | |||
3267 | return false; | |||
3268 | } | |||
3269 | } | |||
3270 | ||||
3271 | // If we're currently evaluating the initializer of this declaration, use that | |||
3272 | // in-flight value. | |||
3273 | if (Info.EvaluatingDecl == Base) { | |||
3274 | Result = Info.EvaluatingDeclValue; | |||
3275 | return true; | |||
3276 | } | |||
3277 | ||||
3278 | if (isa<ParmVarDecl>(VD)) { | |||
3279 | // Assume parameters of a potential constant expression are usable in | |||
3280 | // constant expressions. | |||
3281 | if (!Info.checkingPotentialConstantExpression() || | |||
3282 | !Info.CurrentCall->Callee || | |||
3283 | !Info.CurrentCall->Callee->Equals(VD->getDeclContext())) { | |||
3284 | if (Info.getLangOpts().CPlusPlus11) { | |||
3285 | Info.FFDiag(E, diag::note_constexpr_function_param_value_unknown) | |||
3286 | << VD; | |||
3287 | NoteLValueLocation(Info, Base); | |||
3288 | } else { | |||
3289 | Info.FFDiag(E); | |||
3290 | } | |||
3291 | } | |||
3292 | return false; | |||
3293 | } | |||
3294 | ||||
3295 | // Dig out the initializer, and use the declaration which it's attached to. | |||
3296 | // FIXME: We should eventually check whether the variable has a reachable | |||
3297 | // initializing declaration. | |||
3298 | const Expr *Init = VD->getAnyInitializer(VD); | |||
3299 | if (!Init) { | |||
3300 | // Don't diagnose during potential constant expression checking; an | |||
3301 | // initializer might be added later. | |||
3302 | if (!Info.checkingPotentialConstantExpression()) { | |||
3303 | Info.FFDiag(E, diag::note_constexpr_var_init_unknown, 1) | |||
3304 | << VD; | |||
3305 | NoteLValueLocation(Info, Base); | |||
3306 | } | |||
3307 | return false; | |||
3308 | } | |||
3309 | ||||
3310 | if (Init->isValueDependent()) { | |||
3311 | // The DeclRefExpr is not value-dependent, but the variable it refers to | |||
3312 | // has a value-dependent initializer. This should only happen in | |||
3313 | // constant-folding cases, where the variable is not actually of a suitable | |||
3314 | // type for use in a constant expression (otherwise the DeclRefExpr would | |||
3315 | // have been value-dependent too), so diagnose that. | |||
3316 | assert(!VD->mightBeUsableInConstantExpressions(Info.Ctx))(static_cast <bool> (!VD->mightBeUsableInConstantExpressions (Info.Ctx)) ? void (0) : __assert_fail ("!VD->mightBeUsableInConstantExpressions(Info.Ctx)" , "clang/lib/AST/ExprConstant.cpp", 3316, __extension__ __PRETTY_FUNCTION__ )); | |||
3317 | if (!Info.checkingPotentialConstantExpression()) { | |||
3318 | Info.FFDiag(E, Info.getLangOpts().CPlusPlus11 | |||
3319 | ? diag::note_constexpr_ltor_non_constexpr | |||
3320 | : diag::note_constexpr_ltor_non_integral, 1) | |||
3321 | << VD << VD->getType(); | |||
3322 | NoteLValueLocation(Info, Base); | |||
3323 | } | |||
3324 | return false; | |||
3325 | } | |||
3326 | ||||
3327 | // Check that we can fold the initializer. In C++, we will have already done | |||
3328 | // this in the cases where it matters for conformance. | |||
3329 | if (!VD->evaluateValue()) { | |||
3330 | Info.FFDiag(E, diag::note_constexpr_var_init_non_constant, 1) << VD; | |||
3331 | NoteLValueLocation(Info, Base); | |||
3332 | return false; | |||
3333 | } | |||
3334 | ||||
3335 | // Check that the variable is actually usable in constant expressions. For a | |||
3336 | // const integral variable or a reference, we might have a non-constant | |||
3337 | // initializer that we can nonetheless evaluate the initializer for. Such | |||
3338 | // variables are not usable in constant expressions. In C++98, the | |||
3339 | // initializer also syntactically needs to be an ICE. | |||
3340 | // | |||
3341 | // FIXME: We don't diagnose cases that aren't potentially usable in constant | |||
3342 | // expressions here; doing so would regress diagnostics for things like | |||
3343 | // reading from a volatile constexpr variable. | |||
3344 | if ((Info.getLangOpts().CPlusPlus && !VD->hasConstantInitialization() && | |||
3345 | VD->mightBeUsableInConstantExpressions(Info.Ctx)) || | |||
3346 | ((Info.getLangOpts().CPlusPlus || Info.getLangOpts().OpenCL) && | |||
3347 | !Info.getLangOpts().CPlusPlus11 && !VD->hasICEInitializer(Info.Ctx))) { | |||
3348 | Info.CCEDiag(E, diag::note_constexpr_var_init_non_constant, 1) << VD; | |||
3349 | NoteLValueLocation(Info, Base); | |||
3350 | } | |||
3351 | ||||
3352 | // Never use the initializer of a weak variable, not even for constant | |||
3353 | // folding. We can't be sure that this is the definition that will be used. | |||
3354 | if (VD->isWeak()) { | |||
3355 | Info.FFDiag(E, diag::note_constexpr_var_init_weak) << VD; | |||
3356 | NoteLValueLocation(Info, Base); | |||
3357 | return false; | |||
3358 | } | |||
3359 | ||||
3360 | Result = VD->getEvaluatedValue(); | |||
3361 | return true; | |||
3362 | } | |||
3363 | ||||
3364 | /// Get the base index of the given base class within an APValue representing | |||
3365 | /// the given derived class. | |||
3366 | static unsigned getBaseIndex(const CXXRecordDecl *Derived, | |||
3367 | const CXXRecordDecl *Base) { | |||
3368 | Base = Base->getCanonicalDecl(); | |||
3369 | unsigned Index = 0; | |||
3370 | for (CXXRecordDecl::base_class_const_iterator I = Derived->bases_begin(), | |||
3371 | E = Derived->bases_end(); I != E; ++I, ++Index) { | |||
3372 | if (I->getType()->getAsCXXRecordDecl()->getCanonicalDecl() == Base) | |||
3373 | return Index; | |||
3374 | } | |||
3375 | ||||
3376 | llvm_unreachable("base class missing from derived class's bases list")::llvm::llvm_unreachable_internal("base class missing from derived class's bases list" , "clang/lib/AST/ExprConstant.cpp", 3376); | |||
3377 | } | |||
3378 | ||||
3379 | /// Extract the value of a character from a string literal. | |||
3380 | static APSInt extractStringLiteralCharacter(EvalInfo &Info, const Expr *Lit, | |||
3381 | uint64_t Index) { | |||
3382 | assert(!isa<SourceLocExpr>(Lit) &&(static_cast <bool> (!isa<SourceLocExpr>(Lit) && "SourceLocExpr should have already been converted to a StringLiteral" ) ? void (0) : __assert_fail ("!isa<SourceLocExpr>(Lit) && \"SourceLocExpr should have already been converted to a StringLiteral\"" , "clang/lib/AST/ExprConstant.cpp", 3383, __extension__ __PRETTY_FUNCTION__ )) | |||
3383 | "SourceLocExpr should have already been converted to a StringLiteral")(static_cast <bool> (!isa<SourceLocExpr>(Lit) && "SourceLocExpr should have already been converted to a StringLiteral" ) ? void (0) : __assert_fail ("!isa<SourceLocExpr>(Lit) && \"SourceLocExpr should have already been converted to a StringLiteral\"" , "clang/lib/AST/ExprConstant.cpp", 3383, __extension__ __PRETTY_FUNCTION__ )); | |||
3384 | ||||
3385 | // FIXME: Support MakeStringConstant | |||
3386 | if (const auto *ObjCEnc = dyn_cast<ObjCEncodeExpr>(Lit)) { | |||
3387 | std::string Str; | |||
3388 | Info.Ctx.getObjCEncodingForType(ObjCEnc->getEncodedType(), Str); | |||
3389 | assert(Index <= Str.size() && "Index too large")(static_cast <bool> (Index <= Str.size() && "Index too large" ) ? void (0) : __assert_fail ("Index <= Str.size() && \"Index too large\"" , "clang/lib/AST/ExprConstant.cpp", 3389, __extension__ __PRETTY_FUNCTION__ )); | |||
3390 | return APSInt::getUnsigned(Str.c_str()[Index]); | |||
3391 | } | |||
3392 | ||||
3393 | if (auto PE = dyn_cast<PredefinedExpr>(Lit)) | |||
3394 | Lit = PE->getFunctionName(); | |||
3395 | const StringLiteral *S = cast<StringLiteral>(Lit); | |||
3396 | const ConstantArrayType *CAT = | |||
3397 | Info.Ctx.getAsConstantArrayType(S->getType()); | |||
3398 | assert(CAT && "string literal isn't an array")(static_cast <bool> (CAT && "string literal isn't an array" ) ? void (0) : __assert_fail ("CAT && \"string literal isn't an array\"" , "clang/lib/AST/ExprConstant.cpp", 3398, __extension__ __PRETTY_FUNCTION__ )); | |||
3399 | QualType CharType = CAT->getElementType(); | |||
3400 | assert(CharType->isIntegerType() && "unexpected character type")(static_cast <bool> (CharType->isIntegerType() && "unexpected character type") ? void (0) : __assert_fail ("CharType->isIntegerType() && \"unexpected character type\"" , "clang/lib/AST/ExprConstant.cpp", 3400, __extension__ __PRETTY_FUNCTION__ )); | |||
3401 | ||||
3402 | APSInt Value(S->getCharByteWidth() * Info.Ctx.getCharWidth(), | |||
3403 | CharType->isUnsignedIntegerType()); | |||
3404 | if (Index < S->getLength()) | |||
3405 | Value = S->getCodeUnit(Index); | |||
3406 | return Value; | |||
3407 | } | |||
3408 | ||||
3409 | // Expand a string literal into an array of characters. | |||
3410 | // | |||
3411 | // FIXME: This is inefficient; we should probably introduce something similar | |||
3412 | // to the LLVM ConstantDataArray to make this cheaper. | |||
3413 | static void expandStringLiteral(EvalInfo &Info, const StringLiteral *S, | |||
3414 | APValue &Result, | |||
3415 | QualType AllocType = QualType()) { | |||
3416 | const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType( | |||
3417 | AllocType.isNull() ? S->getType() : AllocType); | |||
3418 | assert(CAT && "string literal isn't an array")(static_cast <bool> (CAT && "string literal isn't an array" ) ? void (0) : __assert_fail ("CAT && \"string literal isn't an array\"" , "clang/lib/AST/ExprConstant.cpp", 3418, __extension__ __PRETTY_FUNCTION__ )); | |||
3419 | QualType CharType = CAT->getElementType(); | |||
3420 | assert(CharType->isIntegerType() && "unexpected character type")(static_cast <bool> (CharType->isIntegerType() && "unexpected character type") ? void (0) : __assert_fail ("CharType->isIntegerType() && \"unexpected character type\"" , "clang/lib/AST/ExprConstant.cpp", 3420, __extension__ __PRETTY_FUNCTION__ )); | |||
3421 | ||||
3422 | unsigned Elts = CAT->getSize().getZExtValue(); | |||
3423 | Result = APValue(APValue::UninitArray(), | |||
3424 | std::min(S->getLength(), Elts), Elts); | |||
3425 | APSInt Value(S->getCharByteWidth() * Info.Ctx.getCharWidth(), | |||
3426 | CharType->isUnsignedIntegerType()); | |||
3427 | if (Result.hasArrayFiller()) | |||
3428 | Result.getArrayFiller() = APValue(Value); | |||
3429 | for (unsigned I = 0, N = Result.getArrayInitializedElts(); I != N; ++I) { | |||
3430 | Value = S->getCodeUnit(I); | |||
3431 | Result.getArrayInitializedElt(I) = APValue(Value); | |||
3432 | } | |||
3433 | } | |||
3434 | ||||
3435 | // Expand an array so that it has more than Index filled elements. | |||
3436 | static void expandArray(APValue &Array, unsigned Index) { | |||
3437 | unsigned Size = Array.getArraySize(); | |||
3438 | assert(Index < Size)(static_cast <bool> (Index < Size) ? void (0) : __assert_fail ("Index < Size", "clang/lib/AST/ExprConstant.cpp", 3438, __extension__ __PRETTY_FUNCTION__)); | |||
3439 | ||||
3440 | // Always at least double the number of elements for which we store a value. | |||
3441 | unsigned OldElts = Array.getArrayInitializedElts(); | |||
3442 | unsigned NewElts = std::max(Index+1, OldElts * 2); | |||
3443 | NewElts = std::min(Size, std::max(NewElts, 8u)); | |||
3444 | ||||
3445 | // Copy the data across. | |||
3446 | APValue NewValue(APValue::UninitArray(), NewElts, Size); | |||
3447 | for (unsigned I = 0; I != OldElts; ++I) | |||
3448 | NewValue.getArrayInitializedElt(I).swap(Array.getArrayInitializedElt(I)); | |||
3449 | for (unsigned I = OldElts; I != NewElts; ++I) | |||
3450 | NewValue.getArrayInitializedElt(I) = Array.getArrayFiller(); | |||
3451 | if (NewValue.hasArrayFiller()) | |||
3452 | NewValue.getArrayFiller() = Array.getArrayFiller(); | |||
3453 | Array.swap(NewValue); | |||
3454 | } | |||
3455 | ||||
3456 | /// Determine whether a type would actually be read by an lvalue-to-rvalue | |||
3457 | /// conversion. If it's of class type, we may assume that the copy operation | |||
3458 | /// is trivial. Note that this is never true for a union type with fields | |||
3459 | /// (because the copy always "reads" the active member) and always true for | |||
3460 | /// a non-class type. | |||
3461 | static bool isReadByLvalueToRvalueConversion(const CXXRecordDecl *RD); | |||
3462 | static bool isReadByLvalueToRvalueConversion(QualType T) { | |||
3463 | CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); | |||
3464 | return !RD || isReadByLvalueToRvalueConversion(RD); | |||
3465 | } | |||
3466 | static bool isReadByLvalueToRvalueConversion(const CXXRecordDecl *RD) { | |||
3467 | // FIXME: A trivial copy of a union copies the object representation, even if | |||
3468 | // the union is empty. | |||
3469 | if (RD->isUnion()) | |||
3470 | return !RD->field_empty(); | |||
3471 | if (RD->isEmpty()) | |||
3472 | return false; | |||
3473 | ||||
3474 | for (auto *Field : RD->fields()) | |||
3475 | if (!Field->isUnnamedBitfield() && | |||
3476 | isReadByLvalueToRvalueConversion(Field->getType())) | |||
3477 | return true; | |||
3478 | ||||
3479 | for (auto &BaseSpec : RD->bases()) | |||
3480 | if (isReadByLvalueToRvalueConversion(BaseSpec.getType())) | |||
3481 | return true; | |||
3482 | ||||
3483 | return false; | |||
3484 | } | |||
3485 | ||||
3486 | /// Diagnose an attempt to read from any unreadable field within the specified | |||
3487 | /// type, which might be a class type. | |||
3488 | static bool diagnoseMutableFields(EvalInfo &Info, const Expr *E, AccessKinds AK, | |||
3489 | QualType T) { | |||
3490 | CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); | |||
3491 | if (!RD) | |||
3492 | return false; | |||
3493 | ||||
3494 | if (!RD->hasMutableFields()) | |||
3495 | return false; | |||
3496 | ||||
3497 | for (auto *Field : RD->fields()) { | |||
3498 | // If we're actually going to read this field in some way, then it can't | |||
3499 | // be mutable. If we're in a union, then assigning to a mutable field | |||
3500 | // (even an empty one) can change the active member, so that's not OK. | |||
3501 | // FIXME: Add core issue number for the union case. | |||
3502 | if (Field->isMutable() && | |||
3503 | (RD->isUnion() || isReadByLvalueToRvalueConversion(Field->getType()))) { | |||
3504 | Info.FFDiag(E, diag::note_constexpr_access_mutable, 1) << AK << Field; | |||
3505 | Info.Note(Field->getLocation(), diag::note_declared_at); | |||
3506 | return true; | |||
3507 | } | |||
3508 | ||||
3509 | if (diagnoseMutableFields(Info, E, AK, Field->getType())) | |||
3510 | return true; | |||
3511 | } | |||
3512 | ||||
3513 | for (auto &BaseSpec : RD->bases()) | |||
3514 | if (diagnoseMutableFields(Info, E, AK, BaseSpec.getType())) | |||
3515 | return true; | |||
3516 | ||||
3517 | // All mutable fields were empty, and thus not actually read. | |||
3518 | return false; | |||
3519 | } | |||
3520 | ||||
3521 | static bool lifetimeStartedInEvaluation(EvalInfo &Info, | |||
3522 | APValue::LValueBase Base, | |||
3523 | bool MutableSubobject = false) { | |||
3524 | // A temporary or transient heap allocation we created. | |||
3525 | if (Base.getCallIndex() || Base.is<DynamicAllocLValue>()) | |||
3526 | return true; | |||
3527 | ||||
3528 | switch (Info.IsEvaluatingDecl) { | |||
3529 | case EvalInfo::EvaluatingDeclKind::None: | |||
3530 | return false; | |||
3531 | ||||
3532 | case EvalInfo::EvaluatingDeclKind::Ctor: | |||
3533 | // The variable whose initializer we're evaluating. | |||
3534 | if (Info.EvaluatingDecl == Base) | |||
3535 | return true; | |||
3536 | ||||
3537 | // A temporary lifetime-extended by the variable whose initializer we're | |||
3538 | // evaluating. | |||
3539 | if (auto *BaseE = Base.dyn_cast<const Expr *>()) | |||
3540 | if (auto *BaseMTE = dyn_cast<MaterializeTemporaryExpr>(BaseE)) | |||
3541 | return Info.EvaluatingDecl == BaseMTE->getExtendingDecl(); | |||
3542 | return false; | |||
3543 | ||||
3544 | case EvalInfo::EvaluatingDeclKind::Dtor: | |||
3545 | // C++2a [expr.const]p6: | |||
3546 | // [during constant destruction] the lifetime of a and its non-mutable | |||
3547 | // subobjects (but not its mutable subobjects) [are] considered to start | |||
3548 | // within e. | |||
3549 | if (MutableSubobject || Base != Info.EvaluatingDecl) | |||
3550 | return false; | |||
3551 | // FIXME: We can meaningfully extend this to cover non-const objects, but | |||
3552 | // we will need special handling: we should be able to access only | |||
3553 | // subobjects of such objects that are themselves declared const. | |||
3554 | QualType T = getType(Base); | |||
3555 | return T.isConstQualified() || T->isReferenceType(); | |||
3556 | } | |||
3557 | ||||
3558 | llvm_unreachable("unknown evaluating decl kind")::llvm::llvm_unreachable_internal("unknown evaluating decl kind" , "clang/lib/AST/ExprConstant.cpp", 3558); | |||
3559 | } | |||
3560 | ||||
3561 | namespace { | |||
3562 | /// A handle to a complete object (an object that is not a subobject of | |||
3563 | /// another object). | |||
3564 | struct CompleteObject { | |||
3565 | /// The identity of the object. | |||
3566 | APValue::LValueBase Base; | |||
3567 | /// The value of the complete object. | |||
3568 | APValue *Value; | |||
3569 | /// The type of the complete object. | |||
3570 | QualType Type; | |||
3571 | ||||
3572 | CompleteObject() : Value(nullptr) {} | |||
3573 | CompleteObject(APValue::LValueBase Base, APValue *Value, QualType Type) | |||
3574 | : Base(Base), Value(Value), Type(Type) {} | |||
3575 | ||||
3576 | bool mayAccessMutableMembers(EvalInfo &Info, AccessKinds AK) const { | |||
3577 | // If this isn't a "real" access (eg, if it's just accessing the type | |||
3578 | // info), allow it. We assume the type doesn't change dynamically for | |||
3579 | // subobjects of constexpr objects (even though we'd hit UB here if it | |||
3580 | // did). FIXME: Is this right? | |||
3581 | if (!isAnyAccess(AK)) | |||
3582 | return true; | |||
3583 | ||||
3584 | // In C++14 onwards, it is permitted to read a mutable member whose | |||
3585 | // lifetime began within the evaluation. | |||
3586 | // FIXME: Should we also allow this in C++11? | |||
3587 | if (!Info.getLangOpts().CPlusPlus14) | |||
3588 | return false; | |||
3589 | return lifetimeStartedInEvaluation(Info, Base, /*MutableSubobject*/true); | |||
3590 | } | |||
3591 | ||||
3592 | explicit operator bool() const { return !Type.isNull(); } | |||
3593 | }; | |||
3594 | } // end anonymous namespace | |||
3595 | ||||
3596 | static QualType getSubobjectType(QualType ObjType, QualType SubobjType, | |||
3597 | bool IsMutable = false) { | |||
3598 | // C++ [basic.type.qualifier]p1: | |||
3599 | // - A const object is an object of type const T or a non-mutable subobject | |||
3600 | // of a const object. | |||
3601 | if (ObjType.isConstQualified() && !IsMutable) | |||
3602 | SubobjType.addConst(); | |||
3603 | // - A volatile object is an object of type const T or a subobject of a | |||
3604 | // volatile object. | |||
3605 | if (ObjType.isVolatileQualified()) | |||
3606 | SubobjType.addVolatile(); | |||
3607 | return SubobjType; | |||
3608 | } | |||
3609 | ||||
3610 | /// Find the designated sub-object of an rvalue. | |||
3611 | template<typename SubobjectHandler> | |||
3612 | typename SubobjectHandler::result_type | |||
3613 | findSubobject(EvalInfo &Info, const Expr *E, const CompleteObject &Obj, | |||
3614 | const SubobjectDesignator &Sub, SubobjectHandler &handler) { | |||
3615 | if (Sub.Invalid) | |||
3616 | // A diagnostic will have already been produced. | |||
3617 | return handler.failed(); | |||
3618 | if (Sub.isOnePastTheEnd() || Sub.isMostDerivedAnUnsizedArray()) { | |||
3619 | if (Info.getLangOpts().CPlusPlus11) | |||
3620 | Info.FFDiag(E, Sub.isOnePastTheEnd() | |||
3621 | ? diag::note_constexpr_access_past_end | |||
3622 | : diag::note_constexpr_access_unsized_array) | |||
3623 | << handler.AccessKind; | |||
3624 | else | |||
3625 | Info.FFDiag(E); | |||
3626 | return handler.failed(); | |||
3627 | } | |||
3628 | ||||
3629 | APValue *O = Obj.Value; | |||
3630 | QualType ObjType = Obj.Type; | |||
3631 | const FieldDecl *LastField = nullptr; | |||
3632 | const FieldDecl *VolatileField = nullptr; | |||
3633 | ||||
3634 | // Walk the designator's path to find the subobject. | |||
3635 | for (unsigned I = 0, N = Sub.Entries.size(); /**/; ++I) { | |||
3636 | // Reading an indeterminate value is undefined, but assigning over one is OK. | |||
3637 | if ((O->isAbsent() && !(handler.AccessKind == AK_Construct && I == N)) || | |||
3638 | (O->isIndeterminate() && | |||
3639 | !isValidIndeterminateAccess(handler.AccessKind))) { | |||
3640 | if (!Info.checkingPotentialConstantExpression()) | |||
3641 | Info.FFDiag(E, diag::note_constexpr_access_uninit) | |||
3642 | << handler.AccessKind << O->isIndeterminate(); | |||
3643 | return handler.failed(); | |||
3644 | } | |||
3645 | ||||
3646 | // C++ [class.ctor]p5, C++ [class.dtor]p5: | |||
3647 | // const and volatile semantics are not applied on an object under | |||
3648 | // {con,de}struction. | |||
3649 | if ((ObjType.isConstQualified() || ObjType.isVolatileQualified()) && | |||
3650 | ObjType->isRecordType() && | |||
3651 | Info.isEvaluatingCtorDtor( | |||
3652 | Obj.Base, | |||
3653 | llvm::ArrayRef(Sub.Entries.begin(), Sub.Entries.begin() + I)) != | |||
3654 | ConstructionPhase::None) { | |||
3655 | ObjType = Info.Ctx.getCanonicalType(ObjType); | |||
3656 | ObjType.removeLocalConst(); | |||
3657 | ObjType.removeLocalVolatile(); | |||
3658 | } | |||
3659 | ||||
3660 | // If this is our last pass, check that the final object type is OK. | |||
3661 | if (I == N || (I == N - 1 && ObjType->isAnyComplexType())) { | |||
3662 | // Accesses to volatile objects are prohibited. | |||
3663 | if (ObjType.isVolatileQualified() && isFormalAccess(handler.AccessKind)) { | |||
3664 | if (Info.getLangOpts().CPlusPlus) { | |||
3665 | int DiagKind; | |||
3666 | SourceLocation Loc; | |||
3667 | const NamedDecl *Decl = nullptr; | |||
3668 | if (VolatileField) { | |||
3669 | DiagKind = 2; | |||
3670 | Loc = VolatileField->getLocation(); | |||
3671 | Decl = VolatileField; | |||
3672 | } else if (auto *VD = Obj.Base.dyn_cast<const ValueDecl*>()) { | |||
3673 | DiagKind = 1; | |||
3674 | Loc = VD->getLocation(); | |||
3675 | Decl = VD; | |||
3676 | } else { | |||
3677 | DiagKind = 0; | |||
3678 | if (auto *E = Obj.Base.dyn_cast<const Expr *>()) | |||
3679 | Loc = E->getExprLoc(); | |||
3680 | } | |||
3681 | Info.FFDiag(E, diag::note_constexpr_access_volatile_obj, 1) | |||
3682 | << handler.AccessKind << DiagKind << Decl; | |||
3683 | Info.Note(Loc, diag::note_constexpr_volatile_here) << DiagKind; | |||
3684 | } else { | |||
3685 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
3686 | } | |||
3687 | return handler.failed(); | |||
3688 | } | |||
3689 | ||||
3690 | // If we are reading an object of class type, there may still be more | |||
3691 | // things we need to check: if there are any mutable subobjects, we | |||
3692 | // cannot perform this read. (This only happens when performing a trivial | |||
3693 | // copy or assignment.) | |||
3694 | if (ObjType->isRecordType() && | |||
3695 | !Obj.mayAccessMutableMembers(Info, handler.AccessKind) && | |||
3696 | diagnoseMutableFields(Info, E, handler.AccessKind, ObjType)) | |||
3697 | return handler.failed(); | |||
3698 | } | |||
3699 | ||||
3700 | if (I == N) { | |||
3701 | if (!handler.found(*O, ObjType)) | |||
3702 | return false; | |||
3703 | ||||
3704 | // If we modified a bit-field, truncate it to the right width. | |||
3705 | if (isModification(handler.AccessKind) && | |||
3706 | LastField && LastField->isBitField() && | |||
3707 | !truncateBitfieldValue(Info, E, *O, LastField)) | |||
3708 | return false; | |||
3709 | ||||
3710 | return true; | |||
3711 | } | |||
3712 | ||||
3713 | LastField = nullptr; | |||
3714 | if (ObjType->isArrayType()) { | |||
3715 | // Next subobject is an array element. | |||
3716 | const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(ObjType); | |||
3717 | assert(CAT && "vla in literal type?")(static_cast <bool> (CAT && "vla in literal type?" ) ? void (0) : __assert_fail ("CAT && \"vla in literal type?\"" , "clang/lib/AST/ExprConstant.cpp", 3717, __extension__ __PRETTY_FUNCTION__ )); | |||
3718 | uint64_t Index = Sub.Entries[I].getAsArrayIndex(); | |||
3719 | if (CAT->getSize().ule(Index)) { | |||
3720 | // Note, it should not be possible to form a pointer with a valid | |||
3721 | // designator which points more than one past the end of the array. | |||
3722 | if (Info.getLangOpts().CPlusPlus11) | |||
3723 | Info.FFDiag(E, diag::note_constexpr_access_past_end) | |||
3724 | << handler.AccessKind; | |||
3725 | else | |||
3726 | Info.FFDiag(E); | |||
3727 | return handler.failed(); | |||
3728 | } | |||
3729 | ||||
3730 | ObjType = CAT->getElementType(); | |||
3731 | ||||
3732 | if (O->getArrayInitializedElts() > Index) | |||
3733 | O = &O->getArrayInitializedElt(Index); | |||
3734 | else if (!isRead(handler.AccessKind)) { | |||
3735 | expandArray(*O, Index); | |||
3736 | O = &O->getArrayInitializedElt(Index); | |||
3737 | } else | |||
3738 | O = &O->getArrayFiller(); | |||
3739 | } else if (ObjType->isAnyComplexType()) { | |||
3740 | // Next subobject is a complex number. | |||
3741 | uint64_t Index = Sub.Entries[I].getAsArrayIndex(); | |||
3742 | if (Index > 1) { | |||
3743 | if (Info.getLangOpts().CPlusPlus11) | |||
3744 | Info.FFDiag(E, diag::note_constexpr_access_past_end) | |||
3745 | << handler.AccessKind; | |||
3746 | else | |||
3747 | Info.FFDiag(E); | |||
3748 | return handler.failed(); | |||
3749 | } | |||
3750 | ||||
3751 | ObjType = getSubobjectType( | |||
3752 | ObjType, ObjType->castAs<ComplexType>()->getElementType()); | |||
3753 | ||||
3754 | assert(I == N - 1 && "extracting subobject of scalar?")(static_cast <bool> (I == N - 1 && "extracting subobject of scalar?" ) ? void (0) : __assert_fail ("I == N - 1 && \"extracting subobject of scalar?\"" , "clang/lib/AST/ExprConstant.cpp", 3754, __extension__ __PRETTY_FUNCTION__ )); | |||
3755 | if (O->isComplexInt()) { | |||
3756 | return handler.found(Index ? O->getComplexIntImag() | |||
3757 | : O->getComplexIntReal(), ObjType); | |||
3758 | } else { | |||
3759 | assert(O->isComplexFloat())(static_cast <bool> (O->isComplexFloat()) ? void (0) : __assert_fail ("O->isComplexFloat()", "clang/lib/AST/ExprConstant.cpp" , 3759, __extension__ __PRETTY_FUNCTION__)); | |||
3760 | return handler.found(Index ? O->getComplexFloatImag() | |||
3761 | : O->getComplexFloatReal(), ObjType); | |||
3762 | } | |||
3763 | } else if (const FieldDecl *Field = getAsField(Sub.Entries[I])) { | |||
3764 | if (Field->isMutable() && | |||
3765 | !Obj.mayAccessMutableMembers(Info, handler.AccessKind)) { | |||
3766 | Info.FFDiag(E, diag::note_constexpr_access_mutable, 1) | |||
3767 | << handler.AccessKind << Field; | |||
3768 | Info.Note(Field->getLocation(), diag::note_declared_at); | |||
3769 | return handler.failed(); | |||
3770 | } | |||
3771 | ||||
3772 | // Next subobject is a class, struct or union field. | |||
3773 | RecordDecl *RD = ObjType->castAs<RecordType>()->getDecl(); | |||
3774 | if (RD->isUnion()) { | |||
3775 | const FieldDecl *UnionField = O->getUnionField(); | |||
3776 | if (!UnionField || | |||
3777 | UnionField->getCanonicalDecl() != Field->getCanonicalDecl()) { | |||
3778 | if (I == N - 1 && handler.AccessKind == AK_Construct) { | |||
3779 | // Placement new onto an inactive union member makes it active. | |||
3780 | O->setUnion(Field, APValue()); | |||
3781 | } else { | |||
3782 | // FIXME: If O->getUnionValue() is absent, report that there's no | |||
3783 | // active union member rather than reporting the prior active union | |||
3784 | // member. We'll need to fix nullptr_t to not use APValue() as its | |||
3785 | // representation first. | |||
3786 | Info.FFDiag(E, diag::note_constexpr_access_inactive_union_member) | |||
3787 | << handler.AccessKind << Field << !UnionField << UnionField; | |||
3788 | return handler.failed(); | |||
3789 | } | |||
3790 | } | |||
3791 | O = &O->getUnionValue(); | |||
3792 | } else | |||
3793 | O = &O->getStructField(Field->getFieldIndex()); | |||
3794 | ||||
3795 | ObjType = getSubobjectType(ObjType, Field->getType(), Field->isMutable()); | |||
3796 | LastField = Field; | |||
3797 | if (Field->getType().isVolatileQualified()) | |||
3798 | VolatileField = Field; | |||
3799 | } else { | |||
3800 | // Next subobject is a base class. | |||
3801 | const CXXRecordDecl *Derived = ObjType->getAsCXXRecordDecl(); | |||
3802 | const CXXRecordDecl *Base = getAsBaseClass(Sub.Entries[I]); | |||
3803 | O = &O->getStructBase(getBaseIndex(Derived, Base)); | |||
3804 | ||||
3805 | ObjType = getSubobjectType(ObjType, Info.Ctx.getRecordType(Base)); | |||
3806 | } | |||
3807 | } | |||
3808 | } | |||
3809 | ||||
3810 | namespace { | |||
3811 | struct ExtractSubobjectHandler { | |||
3812 | EvalInfo &Info; | |||
3813 | const Expr *E; | |||
3814 | APValue &Result; | |||
3815 | const AccessKinds AccessKind; | |||
3816 | ||||
3817 | typedef bool result_type; | |||
3818 | bool failed() { return false; } | |||
3819 | bool found(APValue &Subobj, QualType SubobjType) { | |||
3820 | Result = Subobj; | |||
3821 | if (AccessKind == AK_ReadObjectRepresentation) | |||
3822 | return true; | |||
3823 | return CheckFullyInitialized(Info, E->getExprLoc(), SubobjType, Result); | |||
3824 | } | |||
3825 | bool found(APSInt &Value, QualType SubobjType) { | |||
3826 | Result = APValue(Value); | |||
3827 | return true; | |||
3828 | } | |||
3829 | bool found(APFloat &Value, QualType SubobjType) { | |||
3830 | Result = APValue(Value); | |||
3831 | return true; | |||
3832 | } | |||
3833 | }; | |||
3834 | } // end anonymous namespace | |||
3835 | ||||
3836 | /// Extract the designated sub-object of an rvalue. | |||
3837 | static bool extractSubobject(EvalInfo &Info, const Expr *E, | |||
3838 | const CompleteObject &Obj, | |||
3839 | const SubobjectDesignator &Sub, APValue &Result, | |||
3840 | AccessKinds AK = AK_Read) { | |||
3841 | assert(AK == AK_Read || AK == AK_ReadObjectRepresentation)(static_cast <bool> (AK == AK_Read || AK == AK_ReadObjectRepresentation ) ? void (0) : __assert_fail ("AK == AK_Read || AK == AK_ReadObjectRepresentation" , "clang/lib/AST/ExprConstant.cpp", 3841, __extension__ __PRETTY_FUNCTION__ )); | |||
3842 | ExtractSubobjectHandler Handler = {Info, E, Result, AK}; | |||
3843 | return findSubobject(Info, E, Obj, Sub, Handler); | |||
3844 | } | |||
3845 | ||||
3846 | namespace { | |||
3847 | struct ModifySubobjectHandler { | |||
3848 | EvalInfo &Info; | |||
3849 | APValue &NewVal; | |||
3850 | const Expr *E; | |||
3851 | ||||
3852 | typedef bool result_type; | |||
3853 | static const AccessKinds AccessKind = AK_Assign; | |||
3854 | ||||
3855 | bool checkConst(QualType QT) { | |||
3856 | // Assigning to a const object has undefined behavior. | |||
3857 | if (QT.isConstQualified()) { | |||
3858 | Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT; | |||
3859 | return false; | |||
3860 | } | |||
3861 | return true; | |||
3862 | } | |||
3863 | ||||
3864 | bool failed() { return false; } | |||
3865 | bool found(APValue &Subobj, QualType SubobjType) { | |||
3866 | if (!checkConst(SubobjType)) | |||
3867 | return false; | |||
3868 | // We've been given ownership of NewVal, so just swap it in. | |||
3869 | Subobj.swap(NewVal); | |||
3870 | return true; | |||
3871 | } | |||
3872 | bool found(APSInt &Value, QualType SubobjType) { | |||
3873 | if (!checkConst(SubobjType)) | |||
3874 | return false; | |||
3875 | if (!NewVal.isInt()) { | |||
3876 | // Maybe trying to write a cast pointer value into a complex? | |||
3877 | Info.FFDiag(E); | |||
3878 | return false; | |||
3879 | } | |||
3880 | Value = NewVal.getInt(); | |||
3881 | return true; | |||
3882 | } | |||
3883 | bool found(APFloat &Value, QualType SubobjType) { | |||
3884 | if (!checkConst(SubobjType)) | |||
3885 | return false; | |||
3886 | Value = NewVal.getFloat(); | |||
3887 | return true; | |||
3888 | } | |||
3889 | }; | |||
3890 | } // end anonymous namespace | |||
3891 | ||||
3892 | const AccessKinds ModifySubobjectHandler::AccessKind; | |||
3893 | ||||
3894 | /// Update the designated sub-object of an rvalue to the given value. | |||
3895 | static bool modifySubobject(EvalInfo &Info, const Expr *E, | |||
3896 | const CompleteObject &Obj, | |||
3897 | const SubobjectDesignator &Sub, | |||
3898 | APValue &NewVal) { | |||
3899 | ModifySubobjectHandler Handler = { Info, NewVal, E }; | |||
3900 | return findSubobject(Info, E, Obj, Sub, Handler); | |||
3901 | } | |||
3902 | ||||
3903 | /// Find the position where two subobject designators diverge, or equivalently | |||
3904 | /// the length of the common initial subsequence. | |||
3905 | static unsigned FindDesignatorMismatch(QualType ObjType, | |||
3906 | const SubobjectDesignator &A, | |||
3907 | const SubobjectDesignator &B, | |||
3908 | bool &WasArrayIndex) { | |||
3909 | unsigned I = 0, N = std::min(A.Entries.size(), B.Entries.size()); | |||
3910 | for (/**/; I != N; ++I) { | |||
3911 | if (!ObjType.isNull() && | |||
3912 | (ObjType->isArrayType() || ObjType->isAnyComplexType())) { | |||
3913 | // Next subobject is an array element. | |||
3914 | if (A.Entries[I].getAsArrayIndex() != B.Entries[I].getAsArrayIndex()) { | |||
3915 | WasArrayIndex = true; | |||
3916 | return I; | |||
3917 | } | |||
3918 | if (ObjType->isAnyComplexType()) | |||
3919 | ObjType = ObjType->castAs<ComplexType>()->getElementType(); | |||
3920 | else | |||
3921 | ObjType = ObjType->castAsArrayTypeUnsafe()->getElementType(); | |||
3922 | } else { | |||
3923 | if (A.Entries[I].getAsBaseOrMember() != | |||
3924 | B.Entries[I].getAsBaseOrMember()) { | |||
3925 | WasArrayIndex = false; | |||
3926 | return I; | |||
3927 | } | |||
3928 | if (const FieldDecl *FD = getAsField(A.Entries[I])) | |||
3929 | // Next subobject is a field. | |||
3930 | ObjType = FD->getType(); | |||
3931 | else | |||
3932 | // Next subobject is a base class. | |||
3933 | ObjType = QualType(); | |||
3934 | } | |||
3935 | } | |||
3936 | WasArrayIndex = false; | |||
3937 | return I; | |||
3938 | } | |||
3939 | ||||
3940 | /// Determine whether the given subobject designators refer to elements of the | |||
3941 | /// same array object. | |||
3942 | static bool AreElementsOfSameArray(QualType ObjType, | |||
3943 | const SubobjectDesignator &A, | |||
3944 | const SubobjectDesignator &B) { | |||
3945 | if (A.Entries.size() != B.Entries.size()) | |||
3946 | return false; | |||
3947 | ||||
3948 | bool IsArray = A.MostDerivedIsArrayElement; | |||
3949 | if (IsArray && A.MostDerivedPathLength != A.Entries.size()) | |||
3950 | // A is a subobject of the array element. | |||
3951 | return false; | |||
3952 | ||||
3953 | // If A (and B) designates an array element, the last entry will be the array | |||
3954 | // index. That doesn't have to match. Otherwise, we're in the 'implicit array | |||
3955 | // of length 1' case, and the entire path must match. | |||
3956 | bool WasArrayIndex; | |||
3957 | unsigned CommonLength = FindDesignatorMismatch(ObjType, A, B, WasArrayIndex); | |||
3958 | return CommonLength >= A.Entries.size() - IsArray; | |||
3959 | } | |||
3960 | ||||
3961 | /// Find the complete object to which an LValue refers. | |||
3962 | static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E, | |||
3963 | AccessKinds AK, const LValue &LVal, | |||
3964 | QualType LValType) { | |||
3965 | if (LVal.InvalidBase) { | |||
3966 | Info.FFDiag(E); | |||
3967 | return CompleteObject(); | |||
3968 | } | |||
3969 | ||||
3970 | if (!LVal.Base) { | |||
3971 | Info.FFDiag(E, diag::note_constexpr_access_null) << AK; | |||
3972 | return CompleteObject(); | |||
3973 | } | |||
3974 | ||||
3975 | CallStackFrame *Frame = nullptr; | |||
3976 | unsigned Depth = 0; | |||
3977 | if (LVal.getLValueCallIndex()) { | |||
3978 | std::tie(Frame, Depth) = | |||
3979 | Info.getCallFrameAndDepth(LVal.getLValueCallIndex()); | |||
3980 | if (!Frame) { | |||
3981 | Info.FFDiag(E, diag::note_constexpr_lifetime_ended, 1) | |||
3982 | << AK << LVal.Base.is<const ValueDecl*>(); | |||
3983 | NoteLValueLocation(Info, LVal.Base); | |||
3984 | return CompleteObject(); | |||
3985 | } | |||
3986 | } | |||
3987 | ||||
3988 | bool IsAccess = isAnyAccess(AK); | |||
3989 | ||||
3990 | // C++11 DR1311: An lvalue-to-rvalue conversion on a volatile-qualified type | |||
3991 | // is not a constant expression (even if the object is non-volatile). We also | |||
3992 | // apply this rule to C++98, in order to conform to the expected 'volatile' | |||
3993 | // semantics. | |||
3994 | if (isFormalAccess(AK) && LValType.isVolatileQualified()) { | |||
3995 | if (Info.getLangOpts().CPlusPlus) | |||
3996 | Info.FFDiag(E, diag::note_constexpr_access_volatile_type) | |||
3997 | << AK << LValType; | |||
3998 | else | |||
3999 | Info.FFDiag(E); | |||
4000 | return CompleteObject(); | |||
4001 | } | |||
4002 | ||||
4003 | // Compute value storage location and type of base object. | |||
4004 | APValue *BaseVal = nullptr; | |||
4005 | QualType BaseType = getType(LVal.Base); | |||
4006 | ||||
4007 | if (Info.getLangOpts().CPlusPlus14 && LVal.Base == Info.EvaluatingDecl && | |||
4008 | lifetimeStartedInEvaluation(Info, LVal.Base)) { | |||
4009 | // This is the object whose initializer we're evaluating, so its lifetime | |||
4010 | // started in the current evaluation. | |||
4011 | BaseVal = Info.EvaluatingDeclValue; | |||
4012 | } else if (const ValueDecl *D = LVal.Base.dyn_cast<const ValueDecl *>()) { | |||
4013 | // Allow reading from a GUID declaration. | |||
4014 | if (auto *GD = dyn_cast<MSGuidDecl>(D)) { | |||
4015 | if (isModification(AK)) { | |||
4016 | // All the remaining cases do not permit modification of the object. | |||
4017 | Info.FFDiag(E, diag::note_constexpr_modify_global); | |||
4018 | return CompleteObject(); | |||
4019 | } | |||
4020 | APValue &V = GD->getAsAPValue(); | |||
4021 | if (V.isAbsent()) { | |||
4022 | Info.FFDiag(E, diag::note_constexpr_unsupported_layout) | |||
4023 | << GD->getType(); | |||
4024 | return CompleteObject(); | |||
4025 | } | |||
4026 | return CompleteObject(LVal.Base, &V, GD->getType()); | |||
4027 | } | |||
4028 | ||||
4029 | // Allow reading the APValue from an UnnamedGlobalConstantDecl. | |||
4030 | if (auto *GCD = dyn_cast<UnnamedGlobalConstantDecl>(D)) { | |||
4031 | if (isModification(AK)) { | |||
4032 | Info.FFDiag(E, diag::note_constexpr_modify_global); | |||
4033 | return CompleteObject(); | |||
4034 | } | |||
4035 | return CompleteObject(LVal.Base, const_cast<APValue *>(&GCD->getValue()), | |||
4036 | GCD->getType()); | |||
4037 | } | |||
4038 | ||||
4039 | // Allow reading from template parameter objects. | |||
4040 | if (auto *TPO = dyn_cast<TemplateParamObjectDecl>(D)) { | |||
4041 | if (isModification(AK)) { | |||
4042 | Info.FFDiag(E, diag::note_constexpr_modify_global); | |||
4043 | return CompleteObject(); | |||
4044 | } | |||
4045 | return CompleteObject(LVal.Base, const_cast<APValue *>(&TPO->getValue()), | |||
4046 | TPO->getType()); | |||
4047 | } | |||
4048 | ||||
4049 | // In C++98, const, non-volatile integers initialized with ICEs are ICEs. | |||
4050 | // In C++11, constexpr, non-volatile variables initialized with constant | |||
4051 | // expressions are constant expressions too. Inside constexpr functions, | |||
4052 | // parameters are constant expressions even if they're non-const. | |||
4053 | // In C++1y, objects local to a constant expression (those with a Frame) are | |||
4054 | // both readable and writable inside constant expressions. | |||
4055 | // In C, such things can also be folded, although they are not ICEs. | |||
4056 | const VarDecl *VD = dyn_cast<VarDecl>(D); | |||
4057 | if (VD) { | |||
4058 | if (const VarDecl *VDef = VD->getDefinition(Info.Ctx)) | |||
4059 | VD = VDef; | |||
4060 | } | |||
4061 | if (!VD || VD->isInvalidDecl()) { | |||
4062 | Info.FFDiag(E); | |||
4063 | return CompleteObject(); | |||
4064 | } | |||
4065 | ||||
4066 | bool IsConstant = BaseType.isConstant(Info.Ctx); | |||
4067 | ||||
4068 | // Unless we're looking at a local variable or argument in a constexpr call, | |||
4069 | // the variable we're reading must be const. | |||
4070 | if (!Frame) { | |||
4071 | if (IsAccess && isa<ParmVarDecl>(VD)) { | |||
4072 | // Access of a parameter that's not associated with a frame isn't going | |||
4073 | // to work out, but we can leave it to evaluateVarDeclInit to provide a | |||
4074 | // suitable diagnostic. | |||
4075 | } else if (Info.getLangOpts().CPlusPlus14 && | |||
4076 | lifetimeStartedInEvaluation(Info, LVal.Base)) { | |||
4077 | // OK, we can read and modify an object if we're in the process of | |||
4078 | // evaluating its initializer, because its lifetime began in this | |||
4079 | // evaluation. | |||
4080 | } else if (isModification(AK)) { | |||
4081 | // All the remaining cases do not permit modification of the object. | |||
4082 | Info.FFDiag(E, diag::note_constexpr_modify_global); | |||
4083 | return CompleteObject(); | |||
4084 | } else if (VD->isConstexpr()) { | |||
4085 | // OK, we can read this variable. | |||
4086 | } else if (BaseType->isIntegralOrEnumerationType()) { | |||
4087 | if (!IsConstant) { | |||
4088 | if (!IsAccess) | |||
4089 | return CompleteObject(LVal.getLValueBase(), nullptr, BaseType); | |||
4090 | if (Info.getLangOpts().CPlusPlus) { | |||
4091 | Info.FFDiag(E, diag::note_constexpr_ltor_non_const_int, 1) << VD; | |||
4092 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
4093 | } else { | |||
4094 | Info.FFDiag(E); | |||
4095 | } | |||
4096 | return CompleteObject(); | |||
4097 | } | |||
4098 | } else if (!IsAccess) { | |||
4099 | return CompleteObject(LVal.getLValueBase(), nullptr, BaseType); | |||
4100 | } else if (IsConstant && Info.checkingPotentialConstantExpression() && | |||
4101 | BaseType->isLiteralType(Info.Ctx) && !VD->hasDefinition()) { | |||
4102 | // This variable might end up being constexpr. Don't diagnose it yet. | |||
4103 | } else if (IsConstant) { | |||
4104 | // Keep evaluating to see what we can do. In particular, we support | |||
4105 | // folding of const floating-point types, in order to make static const | |||
4106 | // data members of such types (supported as an extension) more useful. | |||
4107 | if (Info.getLangOpts().CPlusPlus) { | |||
4108 | Info.CCEDiag(E, Info.getLangOpts().CPlusPlus11 | |||
4109 | ? diag::note_constexpr_ltor_non_constexpr | |||
4110 | : diag::note_constexpr_ltor_non_integral, 1) | |||
4111 | << VD << BaseType; | |||
4112 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
4113 | } else { | |||
4114 | Info.CCEDiag(E); | |||
4115 | } | |||
4116 | } else { | |||
4117 | // Never allow reading a non-const value. | |||
4118 | if (Info.getLangOpts().CPlusPlus) { | |||
4119 | Info.FFDiag(E, Info.getLangOpts().CPlusPlus11 | |||
4120 | ? diag::note_constexpr_ltor_non_constexpr | |||
4121 | : diag::note_constexpr_ltor_non_integral, 1) | |||
4122 | << VD << BaseType; | |||
4123 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
4124 | } else { | |||
4125 | Info.FFDiag(E); | |||
4126 | } | |||
4127 | return CompleteObject(); | |||
4128 | } | |||
4129 | } | |||
4130 | ||||
4131 | if (!evaluateVarDeclInit(Info, E, VD, Frame, LVal.getLValueVersion(), BaseVal)) | |||
4132 | return CompleteObject(); | |||
4133 | } else if (DynamicAllocLValue DA = LVal.Base.dyn_cast<DynamicAllocLValue>()) { | |||
4134 | std::optional<DynAlloc *> Alloc = Info.lookupDynamicAlloc(DA); | |||
4135 | if (!Alloc) { | |||
4136 | Info.FFDiag(E, diag::note_constexpr_access_deleted_object) << AK; | |||
4137 | return CompleteObject(); | |||
4138 | } | |||
4139 | return CompleteObject(LVal.Base, &(*Alloc)->Value, | |||
4140 | LVal.Base.getDynamicAllocType()); | |||
4141 | } else { | |||
4142 | const Expr *Base = LVal.Base.dyn_cast<const Expr*>(); | |||
4143 | ||||
4144 | if (!Frame) { | |||
4145 | if (const MaterializeTemporaryExpr *MTE = | |||
4146 | dyn_cast_or_null<MaterializeTemporaryExpr>(Base)) { | |||
4147 | assert(MTE->getStorageDuration() == SD_Static &&(static_cast <bool> (MTE->getStorageDuration() == SD_Static && "should have a frame for a non-global materialized temporary" ) ? void (0) : __assert_fail ("MTE->getStorageDuration() == SD_Static && \"should have a frame for a non-global materialized temporary\"" , "clang/lib/AST/ExprConstant.cpp", 4148, __extension__ __PRETTY_FUNCTION__ )) | |||
4148 | "should have a frame for a non-global materialized temporary")(static_cast <bool> (MTE->getStorageDuration() == SD_Static && "should have a frame for a non-global materialized temporary" ) ? void (0) : __assert_fail ("MTE->getStorageDuration() == SD_Static && \"should have a frame for a non-global materialized temporary\"" , "clang/lib/AST/ExprConstant.cpp", 4148, __extension__ __PRETTY_FUNCTION__ )); | |||
4149 | ||||
4150 | // C++20 [expr.const]p4: [DR2126] | |||
4151 | // An object or reference is usable in constant expressions if it is | |||
4152 | // - a temporary object of non-volatile const-qualified literal type | |||
4153 | // whose lifetime is extended to that of a variable that is usable | |||
4154 | // in constant expressions | |||
4155 | // | |||
4156 | // C++20 [expr.const]p5: | |||
4157 | // an lvalue-to-rvalue conversion [is not allowed unless it applies to] | |||
4158 | // - a non-volatile glvalue that refers to an object that is usable | |||
4159 | // in constant expressions, or | |||
4160 | // - a non-volatile glvalue of literal type that refers to a | |||
4161 | // non-volatile object whose lifetime began within the evaluation | |||
4162 | // of E; | |||
4163 | // | |||
4164 | // C++11 misses the 'began within the evaluation of e' check and | |||
4165 | // instead allows all temporaries, including things like: | |||
4166 | // int &&r = 1; | |||
4167 | // int x = ++r; | |||
4168 | // constexpr int k = r; | |||
4169 | // Therefore we use the C++14-onwards rules in C++11 too. | |||
4170 | // | |||
4171 | // Note that temporaries whose lifetimes began while evaluating a | |||
4172 | // variable's constructor are not usable while evaluating the | |||
4173 | // corresponding destructor, not even if they're of const-qualified | |||
4174 | // types. | |||
4175 | if (!MTE->isUsableInConstantExpressions(Info.Ctx) && | |||
4176 | !lifetimeStartedInEvaluation(Info, LVal.Base)) { | |||
4177 | if (!IsAccess) | |||
4178 | return CompleteObject(LVal.getLValueBase(), nullptr, BaseType); | |||
4179 | Info.FFDiag(E, diag::note_constexpr_access_static_temporary, 1) << AK; | |||
4180 | Info.Note(MTE->getExprLoc(), diag::note_constexpr_temporary_here); | |||
4181 | return CompleteObject(); | |||
4182 | } | |||
4183 | ||||
4184 | BaseVal = MTE->getOrCreateValue(false); | |||
4185 | assert(BaseVal && "got reference to unevaluated temporary")(static_cast <bool> (BaseVal && "got reference to unevaluated temporary" ) ? void (0) : __assert_fail ("BaseVal && \"got reference to unevaluated temporary\"" , "clang/lib/AST/ExprConstant.cpp", 4185, __extension__ __PRETTY_FUNCTION__ )); | |||
4186 | } else { | |||
4187 | if (!IsAccess) | |||
4188 | return CompleteObject(LVal.getLValueBase(), nullptr, BaseType); | |||
4189 | APValue Val; | |||
4190 | LVal.moveInto(Val); | |||
4191 | Info.FFDiag(E, diag::note_constexpr_access_unreadable_object) | |||
4192 | << AK | |||
4193 | << Val.getAsString(Info.Ctx, | |||
4194 | Info.Ctx.getLValueReferenceType(LValType)); | |||
4195 | NoteLValueLocation(Info, LVal.Base); | |||
4196 | return CompleteObject(); | |||
4197 | } | |||
4198 | } else { | |||
4199 | BaseVal = Frame->getTemporary(Base, LVal.Base.getVersion()); | |||
4200 | assert(BaseVal && "missing value for temporary")(static_cast <bool> (BaseVal && "missing value for temporary" ) ? void (0) : __assert_fail ("BaseVal && \"missing value for temporary\"" , "clang/lib/AST/ExprConstant.cpp", 4200, __extension__ __PRETTY_FUNCTION__ )); | |||
4201 | } | |||
4202 | } | |||
4203 | ||||
4204 | // In C++14, we can't safely access any mutable state when we might be | |||
4205 | // evaluating after an unmodeled side effect. Parameters are modeled as state | |||
4206 | // in the caller, but aren't visible once the call returns, so they can be | |||
4207 | // modified in a speculatively-evaluated call. | |||
4208 | // | |||
4209 | // FIXME: Not all local state is mutable. Allow local constant subobjects | |||
4210 | // to be read here (but take care with 'mutable' fields). | |||
4211 | unsigned VisibleDepth = Depth; | |||
4212 | if (llvm::isa_and_nonnull<ParmVarDecl>( | |||
4213 | LVal.Base.dyn_cast<const ValueDecl *>())) | |||
4214 | ++VisibleDepth; | |||
4215 | if ((Frame && Info.getLangOpts().CPlusPlus14 && | |||
4216 | Info.EvalStatus.HasSideEffects) || | |||
4217 | (isModification(AK) && VisibleDepth < Info.SpeculativeEvaluationDepth)) | |||
4218 | return CompleteObject(); | |||
4219 | ||||
4220 | return CompleteObject(LVal.getLValueBase(), BaseVal, BaseType); | |||
4221 | } | |||
4222 | ||||
4223 | /// Perform an lvalue-to-rvalue conversion on the given glvalue. This | |||
4224 | /// can also be used for 'lvalue-to-lvalue' conversions for looking up the | |||
4225 | /// glvalue referred to by an entity of reference type. | |||
4226 | /// | |||
4227 | /// \param Info - Information about the ongoing evaluation. | |||
4228 | /// \param Conv - The expression for which we are performing the conversion. | |||
4229 | /// Used for diagnostics. | |||
4230 | /// \param Type - The type of the glvalue (before stripping cv-qualifiers in the | |||
4231 | /// case of a non-class type). | |||
4232 | /// \param LVal - The glvalue on which we are attempting to perform this action. | |||
4233 | /// \param RVal - The produced value will be placed here. | |||
4234 | /// \param WantObjectRepresentation - If true, we're looking for the object | |||
4235 | /// representation rather than the value, and in particular, | |||
4236 | /// there is no requirement that the result be fully initialized. | |||
4237 | static bool | |||
4238 | handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv, QualType Type, | |||
4239 | const LValue &LVal, APValue &RVal, | |||
4240 | bool WantObjectRepresentation = false) { | |||
4241 | if (LVal.Designator.Invalid) | |||
4242 | return false; | |||
4243 | ||||
4244 | // Check for special cases where there is no existing APValue to look at. | |||
4245 | const Expr *Base = LVal.Base.dyn_cast<const Expr*>(); | |||
4246 | ||||
4247 | AccessKinds AK = | |||
4248 | WantObjectRepresentation ? AK_ReadObjectRepresentation : AK_Read; | |||
4249 | ||||
4250 | if (Base && !LVal.getLValueCallIndex() && !Type.isVolatileQualified()) { | |||
4251 | if (const CompoundLiteralExpr *CLE = dyn_cast<CompoundLiteralExpr>(Base)) { | |||
4252 | // In C99, a CompoundLiteralExpr is an lvalue, and we defer evaluating the | |||
4253 | // initializer until now for such expressions. Such an expression can't be | |||
4254 | // an ICE in C, so this only matters for fold. | |||
4255 | if (Type.isVolatileQualified()) { | |||
4256 | Info.FFDiag(Conv); | |||
4257 | return false; | |||
4258 | } | |||
4259 | ||||
4260 | APValue Lit; | |||
4261 | if (!Evaluate(Lit, Info, CLE->getInitializer())) | |||
4262 | return false; | |||
4263 | ||||
4264 | // According to GCC info page: | |||
4265 | // | |||
4266 | // 6.28 Compound Literals | |||
4267 | // | |||
4268 | // As an optimization, G++ sometimes gives array compound literals longer | |||
4269 | // lifetimes: when the array either appears outside a function or has a | |||
4270 | // const-qualified type. If foo and its initializer had elements of type | |||
4271 | // char *const rather than char *, or if foo were a global variable, the | |||
4272 | // array would have static storage duration. But it is probably safest | |||
4273 | // just to avoid the use of array compound literals in C++ code. | |||
4274 | // | |||
4275 | // Obey that rule by checking constness for converted array types. | |||
4276 | ||||
4277 | QualType CLETy = CLE->getType(); | |||
4278 | if (CLETy->isArrayType() && !Type->isArrayType()) { | |||
4279 | if (!CLETy.isConstant(Info.Ctx)) { | |||
4280 | Info.FFDiag(Conv); | |||
4281 | Info.Note(CLE->getExprLoc(), diag::note_declared_at); | |||
4282 | return false; | |||
4283 | } | |||
4284 | } | |||
4285 | ||||
4286 | CompleteObject LitObj(LVal.Base, &Lit, Base->getType()); | |||
4287 | return extractSubobject(Info, Conv, LitObj, LVal.Designator, RVal, AK); | |||
4288 | } else if (isa<StringLiteral>(Base) || isa<PredefinedExpr>(Base)) { | |||
4289 | // Special-case character extraction so we don't have to construct an | |||
4290 | // APValue for the whole string. | |||
4291 | assert(LVal.Designator.Entries.size() <= 1 &&(static_cast <bool> (LVal.Designator.Entries.size() <= 1 && "Can only read characters from string literals" ) ? void (0) : __assert_fail ("LVal.Designator.Entries.size() <= 1 && \"Can only read characters from string literals\"" , "clang/lib/AST/ExprConstant.cpp", 4292, __extension__ __PRETTY_FUNCTION__ )) | |||
4292 | "Can only read characters from string literals")(static_cast <bool> (LVal.Designator.Entries.size() <= 1 && "Can only read characters from string literals" ) ? void (0) : __assert_fail ("LVal.Designator.Entries.size() <= 1 && \"Can only read characters from string literals\"" , "clang/lib/AST/ExprConstant.cpp", 4292, __extension__ __PRETTY_FUNCTION__ )); | |||
4293 | if (LVal.Designator.Entries.empty()) { | |||
4294 | // Fail for now for LValue to RValue conversion of an array. | |||
4295 | // (This shouldn't show up in C/C++, but it could be triggered by a | |||
4296 | // weird EvaluateAsRValue call from a tool.) | |||
4297 | Info.FFDiag(Conv); | |||
4298 | return false; | |||
4299 | } | |||
4300 | if (LVal.Designator.isOnePastTheEnd()) { | |||
4301 | if (Info.getLangOpts().CPlusPlus11) | |||
4302 | Info.FFDiag(Conv, diag::note_constexpr_access_past_end) << AK; | |||
4303 | else | |||
4304 | Info.FFDiag(Conv); | |||
4305 | return false; | |||
4306 | } | |||
4307 | uint64_t CharIndex = LVal.Designator.Entries[0].getAsArrayIndex(); | |||
4308 | RVal = APValue(extractStringLiteralCharacter(Info, Base, CharIndex)); | |||
4309 | return true; | |||
4310 | } | |||
4311 | } | |||
4312 | ||||
4313 | CompleteObject Obj = findCompleteObject(Info, Conv, AK, LVal, Type); | |||
4314 | return Obj && extractSubobject(Info, Conv, Obj, LVal.Designator, RVal, AK); | |||
4315 | } | |||
4316 | ||||
4317 | /// Perform an assignment of Val to LVal. Takes ownership of Val. | |||
4318 | static bool handleAssignment(EvalInfo &Info, const Expr *E, const LValue &LVal, | |||
4319 | QualType LValType, APValue &Val) { | |||
4320 | if (LVal.Designator.Invalid) | |||
4321 | return false; | |||
4322 | ||||
4323 | if (!Info.getLangOpts().CPlusPlus14) { | |||
4324 | Info.FFDiag(E); | |||
4325 | return false; | |||
4326 | } | |||
4327 | ||||
4328 | CompleteObject Obj = findCompleteObject(Info, E, AK_Assign, LVal, LValType); | |||
4329 | return Obj && modifySubobject(Info, E, Obj, LVal.Designator, Val); | |||
4330 | } | |||
4331 | ||||
4332 | namespace { | |||
4333 | struct CompoundAssignSubobjectHandler { | |||
4334 | EvalInfo &Info; | |||
4335 | const CompoundAssignOperator *E; | |||
4336 | QualType PromotedLHSType; | |||
4337 | BinaryOperatorKind Opcode; | |||
4338 | const APValue &RHS; | |||
4339 | ||||
4340 | static const AccessKinds AccessKind = AK_Assign; | |||
4341 | ||||
4342 | typedef bool result_type; | |||
4343 | ||||
4344 | bool checkConst(QualType QT) { | |||
4345 | // Assigning to a const object has undefined behavior. | |||
4346 | if (QT.isConstQualified()) { | |||
4347 | Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT; | |||
4348 | return false; | |||
4349 | } | |||
4350 | return true; | |||
4351 | } | |||
4352 | ||||
4353 | bool failed() { return false; } | |||
4354 | bool found(APValue &Subobj, QualType SubobjType) { | |||
4355 | switch (Subobj.getKind()) { | |||
4356 | case APValue::Int: | |||
4357 | return found(Subobj.getInt(), SubobjType); | |||
4358 | case APValue::Float: | |||
4359 | return found(Subobj.getFloat(), SubobjType); | |||
4360 | case APValue::ComplexInt: | |||
4361 | case APValue::ComplexFloat: | |||
4362 | // FIXME: Implement complex compound assignment. | |||
4363 | Info.FFDiag(E); | |||
4364 | return false; | |||
4365 | case APValue::LValue: | |||
4366 | return foundPointer(Subobj, SubobjType); | |||
4367 | case APValue::Vector: | |||
4368 | return foundVector(Subobj, SubobjType); | |||
4369 | default: | |||
4370 | // FIXME: can this happen? | |||
4371 | Info.FFDiag(E); | |||
4372 | return false; | |||
4373 | } | |||
4374 | } | |||
4375 | ||||
4376 | bool foundVector(APValue &Value, QualType SubobjType) { | |||
4377 | if (!checkConst(SubobjType)) | |||
4378 | return false; | |||
4379 | ||||
4380 | if (!SubobjType->isVectorType()) { | |||
4381 | Info.FFDiag(E); | |||
4382 | return false; | |||
4383 | } | |||
4384 | return handleVectorVectorBinOp(Info, E, Opcode, Value, RHS); | |||
4385 | } | |||
4386 | ||||
4387 | bool found(APSInt &Value, QualType SubobjType) { | |||
4388 | if (!checkConst(SubobjType)) | |||
4389 | return false; | |||
4390 | ||||
4391 | if (!SubobjType->isIntegerType()) { | |||
4392 | // We don't support compound assignment on integer-cast-to-pointer | |||
4393 | // values. | |||
4394 | Info.FFDiag(E); | |||
4395 | return false; | |||
4396 | } | |||
4397 | ||||
4398 | if (RHS.isInt()) { | |||
4399 | APSInt LHS = | |||
4400 | HandleIntToIntCast(Info, E, PromotedLHSType, SubobjType, Value); | |||
4401 | if (!handleIntIntBinOp(Info, E, LHS, Opcode, RHS.getInt(), LHS)) | |||
4402 | return false; | |||
4403 | Value = HandleIntToIntCast(Info, E, SubobjType, PromotedLHSType, LHS); | |||
4404 | return true; | |||
4405 | } else if (RHS.isFloat()) { | |||
4406 | const FPOptions FPO = E->getFPFeaturesInEffect( | |||
4407 | Info.Ctx.getLangOpts()); | |||
4408 | APFloat FValue(0.0); | |||
4409 | return HandleIntToFloatCast(Info, E, FPO, SubobjType, Value, | |||
4410 | PromotedLHSType, FValue) && | |||
4411 | handleFloatFloatBinOp(Info, E, FValue, Opcode, RHS.getFloat()) && | |||
4412 | HandleFloatToIntCast(Info, E, PromotedLHSType, FValue, SubobjType, | |||
4413 | Value); | |||
4414 | } | |||
4415 | ||||
4416 | Info.FFDiag(E); | |||
4417 | return false; | |||
4418 | } | |||
4419 | bool found(APFloat &Value, QualType SubobjType) { | |||
4420 | return checkConst(SubobjType) && | |||
4421 | HandleFloatToFloatCast(Info, E, SubobjType, PromotedLHSType, | |||
4422 | Value) && | |||
4423 | handleFloatFloatBinOp(Info, E, Value, Opcode, RHS.getFloat()) && | |||
4424 | HandleFloatToFloatCast(Info, E, PromotedLHSType, SubobjType, Value); | |||
4425 | } | |||
4426 | bool foundPointer(APValue &Subobj, QualType SubobjType) { | |||
4427 | if (!checkConst(SubobjType)) | |||
4428 | return false; | |||
4429 | ||||
4430 | QualType PointeeType; | |||
4431 | if (const PointerType *PT = SubobjType->getAs<PointerType>()) | |||
4432 | PointeeType = PT->getPointeeType(); | |||
4433 | ||||
4434 | if (PointeeType.isNull() || !RHS.isInt() || | |||
4435 | (Opcode != BO_Add && Opcode != BO_Sub)) { | |||
4436 | Info.FFDiag(E); | |||
4437 | return false; | |||
4438 | } | |||
4439 | ||||
4440 | APSInt Offset = RHS.getInt(); | |||
4441 | if (Opcode == BO_Sub) | |||
4442 | negateAsSigned(Offset); | |||
4443 | ||||
4444 | LValue LVal; | |||
4445 | LVal.setFrom(Info.Ctx, Subobj); | |||
4446 | if (!HandleLValueArrayAdjustment(Info, E, LVal, PointeeType, Offset)) | |||
4447 | return false; | |||
4448 | LVal.moveInto(Subobj); | |||
4449 | return true; | |||
4450 | } | |||
4451 | }; | |||
4452 | } // end anonymous namespace | |||
4453 | ||||
4454 | const AccessKinds CompoundAssignSubobjectHandler::AccessKind; | |||
4455 | ||||
4456 | /// Perform a compound assignment of LVal <op>= RVal. | |||
4457 | static bool handleCompoundAssignment(EvalInfo &Info, | |||
4458 | const CompoundAssignOperator *E, | |||
4459 | const LValue &LVal, QualType LValType, | |||
4460 | QualType PromotedLValType, | |||
4461 | BinaryOperatorKind Opcode, | |||
4462 | const APValue &RVal) { | |||
4463 | if (LVal.Designator.Invalid) | |||
4464 | return false; | |||
4465 | ||||
4466 | if (!Info.getLangOpts().CPlusPlus14) { | |||
4467 | Info.FFDiag(E); | |||
4468 | return false; | |||
4469 | } | |||
4470 | ||||
4471 | CompleteObject Obj = findCompleteObject(Info, E, AK_Assign, LVal, LValType); | |||
4472 | CompoundAssignSubobjectHandler Handler = { Info, E, PromotedLValType, Opcode, | |||
4473 | RVal }; | |||
4474 | return Obj && findSubobject(Info, E, Obj, LVal.Designator, Handler); | |||
4475 | } | |||
4476 | ||||
4477 | namespace { | |||
4478 | struct IncDecSubobjectHandler { | |||
4479 | EvalInfo &Info; | |||
4480 | const UnaryOperator *E; | |||
4481 | AccessKinds AccessKind; | |||
4482 | APValue *Old; | |||
4483 | ||||
4484 | typedef bool result_type; | |||
4485 | ||||
4486 | bool checkConst(QualType QT) { | |||
4487 | // Assigning to a const object has undefined behavior. | |||
4488 | if (QT.isConstQualified()) { | |||
4489 | Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT; | |||
4490 | return false; | |||
4491 | } | |||
4492 | return true; | |||
4493 | } | |||
4494 | ||||
4495 | bool failed() { return false; } | |||
4496 | bool found(APValue &Subobj, QualType SubobjType) { | |||
4497 | // Stash the old value. Also clear Old, so we don't clobber it later | |||
4498 | // if we're post-incrementing a complex. | |||
4499 | if (Old) { | |||
4500 | *Old = Subobj; | |||
4501 | Old = nullptr; | |||
4502 | } | |||
4503 | ||||
4504 | switch (Subobj.getKind()) { | |||
4505 | case APValue::Int: | |||
4506 | return found(Subobj.getInt(), SubobjType); | |||
4507 | case APValue::Float: | |||
4508 | return found(Subobj.getFloat(), SubobjType); | |||
4509 | case APValue::ComplexInt: | |||
4510 | return found(Subobj.getComplexIntReal(), | |||
4511 | SubobjType->castAs<ComplexType>()->getElementType() | |||
4512 | .withCVRQualifiers(SubobjType.getCVRQualifiers())); | |||
4513 | case APValue::ComplexFloat: | |||
4514 | return found(Subobj.getComplexFloatReal(), | |||
4515 | SubobjType->castAs<ComplexType>()->getElementType() | |||
4516 | .withCVRQualifiers(SubobjType.getCVRQualifiers())); | |||
4517 | case APValue::LValue: | |||
4518 | return foundPointer(Subobj, SubobjType); | |||
4519 | default: | |||
4520 | // FIXME: can this happen? | |||
4521 | Info.FFDiag(E); | |||
4522 | return false; | |||
4523 | } | |||
4524 | } | |||
4525 | bool found(APSInt &Value, QualType SubobjType) { | |||
4526 | if (!checkConst(SubobjType)) | |||
4527 | return false; | |||
4528 | ||||
4529 | if (!SubobjType->isIntegerType()) { | |||
4530 | // We don't support increment / decrement on integer-cast-to-pointer | |||
4531 | // values. | |||
4532 | Info.FFDiag(E); | |||
4533 | return false; | |||
4534 | } | |||
4535 | ||||
4536 | if (Old) *Old = APValue(Value); | |||
4537 | ||||
4538 | // bool arithmetic promotes to int, and the conversion back to bool | |||
4539 | // doesn't reduce mod 2^n, so special-case it. | |||
4540 | if (SubobjType->isBooleanType()) { | |||
4541 | if (AccessKind == AK_Increment) | |||
4542 | Value = 1; | |||
4543 | else | |||
4544 | Value = !Value; | |||
4545 | return true; | |||
4546 | } | |||
4547 | ||||
4548 | bool WasNegative = Value.isNegative(); | |||
4549 | if (AccessKind == AK_Increment) { | |||
4550 | ++Value; | |||
4551 | ||||
4552 | if (!WasNegative && Value.isNegative() && E->canOverflow()) { | |||
4553 | APSInt ActualValue(Value, /*IsUnsigned*/true); | |||
4554 | return HandleOverflow(Info, E, ActualValue, SubobjType); | |||
4555 | } | |||
4556 | } else { | |||
4557 | --Value; | |||
4558 | ||||
4559 | if (WasNegative && !Value.isNegative() && E->canOverflow()) { | |||
4560 | unsigned BitWidth = Value.getBitWidth(); | |||
4561 | APSInt ActualValue(Value.sext(BitWidth + 1), /*IsUnsigned*/false); | |||
4562 | ActualValue.setBit(BitWidth); | |||
4563 | return HandleOverflow(Info, E, ActualValue, SubobjType); | |||
4564 | } | |||
4565 | } | |||
4566 | return true; | |||
4567 | } | |||
4568 | bool found(APFloat &Value, QualType SubobjType) { | |||
4569 | if (!checkConst(SubobjType)) | |||
4570 | return false; | |||
4571 | ||||
4572 | if (Old) *Old = APValue(Value); | |||
4573 | ||||
4574 | APFloat One(Value.getSemantics(), 1); | |||
4575 | if (AccessKind == AK_Increment) | |||
4576 | Value.add(One, APFloat::rmNearestTiesToEven); | |||
4577 | else | |||
4578 | Value.subtract(One, APFloat::rmNearestTiesToEven); | |||
4579 | return true; | |||
4580 | } | |||
4581 | bool foundPointer(APValue &Subobj, QualType SubobjType) { | |||
4582 | if (!checkConst(SubobjType)) | |||
4583 | return false; | |||
4584 | ||||
4585 | QualType PointeeType; | |||
4586 | if (const PointerType *PT = SubobjType->getAs<PointerType>()) | |||
4587 | PointeeType = PT->getPointeeType(); | |||
4588 | else { | |||
4589 | Info.FFDiag(E); | |||
4590 | return false; | |||
4591 | } | |||
4592 | ||||
4593 | LValue LVal; | |||
4594 | LVal.setFrom(Info.Ctx, Subobj); | |||
4595 | if (!HandleLValueArrayAdjustment(Info, E, LVal, PointeeType, | |||
4596 | AccessKind == AK_Increment ? 1 : -1)) | |||
4597 | return false; | |||
4598 | LVal.moveInto(Subobj); | |||
4599 | return true; | |||
4600 | } | |||
4601 | }; | |||
4602 | } // end anonymous namespace | |||
4603 | ||||
4604 | /// Perform an increment or decrement on LVal. | |||
4605 | static bool handleIncDec(EvalInfo &Info, const Expr *E, const LValue &LVal, | |||
4606 | QualType LValType, bool IsIncrement, APValue *Old) { | |||
4607 | if (LVal.Designator.Invalid) | |||
4608 | return false; | |||
4609 | ||||
4610 | if (!Info.getLangOpts().CPlusPlus14) { | |||
4611 | Info.FFDiag(E); | |||
4612 | return false; | |||
4613 | } | |||
4614 | ||||
4615 | AccessKinds AK = IsIncrement ? AK_Increment : AK_Decrement; | |||
4616 | CompleteObject Obj = findCompleteObject(Info, E, AK, LVal, LValType); | |||
4617 | IncDecSubobjectHandler Handler = {Info, cast<UnaryOperator>(E), AK, Old}; | |||
4618 | return Obj && findSubobject(Info, E, Obj, LVal.Designator, Handler); | |||
4619 | } | |||
4620 | ||||
4621 | /// Build an lvalue for the object argument of a member function call. | |||
4622 | static bool EvaluateObjectArgument(EvalInfo &Info, const Expr *Object, | |||
4623 | LValue &This) { | |||
4624 | if (Object->getType()->isPointerType() && Object->isPRValue()) | |||
4625 | return EvaluatePointer(Object, This, Info); | |||
4626 | ||||
4627 | if (Object->isGLValue()) | |||
4628 | return EvaluateLValue(Object, This, Info); | |||
4629 | ||||
4630 | if (Object->getType()->isLiteralType(Info.Ctx)) | |||
4631 | return EvaluateTemporary(Object, This, Info); | |||
4632 | ||||
4633 | Info.FFDiag(Object, diag::note_constexpr_nonliteral) << Object->getType(); | |||
4634 | return false; | |||
4635 | } | |||
4636 | ||||
4637 | /// HandleMemberPointerAccess - Evaluate a member access operation and build an | |||
4638 | /// lvalue referring to the result. | |||
4639 | /// | |||
4640 | /// \param Info - Information about the ongoing evaluation. | |||
4641 | /// \param LV - An lvalue referring to the base of the member pointer. | |||
4642 | /// \param RHS - The member pointer expression. | |||
4643 | /// \param IncludeMember - Specifies whether the member itself is included in | |||
4644 | /// the resulting LValue subobject designator. This is not possible when | |||
4645 | /// creating a bound member function. | |||
4646 | /// \return The field or method declaration to which the member pointer refers, | |||
4647 | /// or 0 if evaluation fails. | |||
4648 | static const ValueDecl *HandleMemberPointerAccess(EvalInfo &Info, | |||
4649 | QualType LVType, | |||
4650 | LValue &LV, | |||
4651 | const Expr *RHS, | |||
4652 | bool IncludeMember = true) { | |||
4653 | MemberPtr MemPtr; | |||
4654 | if (!EvaluateMemberPointer(RHS, MemPtr, Info)) | |||
4655 | return nullptr; | |||
4656 | ||||
4657 | // C++11 [expr.mptr.oper]p6: If the second operand is the null pointer to | |||
4658 | // member value, the behavior is undefined. | |||
4659 | if (!MemPtr.getDecl()) { | |||
4660 | // FIXME: Specific diagnostic. | |||
4661 | Info.FFDiag(RHS); | |||
4662 | return nullptr; | |||
4663 | } | |||
4664 | ||||
4665 | if (MemPtr.isDerivedMember()) { | |||
4666 | // This is a member of some derived class. Truncate LV appropriately. | |||
4667 | // The end of the derived-to-base path for the base object must match the | |||
4668 | // derived-to-base path for the member pointer. | |||
4669 | if (LV.Designator.MostDerivedPathLength + MemPtr.Path.size() > | |||
4670 | LV.Designator.Entries.size()) { | |||
4671 | Info.FFDiag(RHS); | |||
4672 | return nullptr; | |||
4673 | } | |||
4674 | unsigned PathLengthToMember = | |||
4675 | LV.Designator.Entries.size() - MemPtr.Path.size(); | |||
4676 | for (unsigned I = 0, N = MemPtr.Path.size(); I != N; ++I) { | |||
4677 | const CXXRecordDecl *LVDecl = getAsBaseClass( | |||
4678 | LV.Designator.Entries[PathLengthToMember + I]); | |||
4679 | const CXXRecordDecl *MPDecl = MemPtr.Path[I]; | |||
4680 | if (LVDecl->getCanonicalDecl() != MPDecl->getCanonicalDecl()) { | |||
4681 | Info.FFDiag(RHS); | |||
4682 | return nullptr; | |||
4683 | } | |||
4684 | } | |||
4685 | ||||
4686 | // Truncate the lvalue to the appropriate derived class. | |||
4687 | if (!CastToDerivedClass(Info, RHS, LV, MemPtr.getContainingRecord(), | |||
4688 | PathLengthToMember)) | |||
4689 | return nullptr; | |||
4690 | } else if (!MemPtr.Path.empty()) { | |||
4691 | // Extend the LValue path with the member pointer's path. | |||
4692 | LV.Designator.Entries.reserve(LV.Designator.Entries.size() + | |||
4693 | MemPtr.Path.size() + IncludeMember); | |||
4694 | ||||
4695 | // Walk down to the appropriate base class. | |||
4696 | if (const PointerType *PT = LVType->getAs<PointerType>()) | |||
4697 | LVType = PT->getPointeeType(); | |||
4698 | const CXXRecordDecl *RD = LVType->getAsCXXRecordDecl(); | |||
4699 | assert(RD && "member pointer access on non-class-type expression")(static_cast <bool> (RD && "member pointer access on non-class-type expression" ) ? void (0) : __assert_fail ("RD && \"member pointer access on non-class-type expression\"" , "clang/lib/AST/ExprConstant.cpp", 4699, __extension__ __PRETTY_FUNCTION__ )); | |||
4700 | // The first class in the path is that of the lvalue. | |||
4701 | for (unsigned I = 1, N = MemPtr.Path.size(); I != N; ++I) { | |||
4702 | const CXXRecordDecl *Base = MemPtr.Path[N - I - 1]; | |||
4703 | if (!HandleLValueDirectBase(Info, RHS, LV, RD, Base)) | |||
4704 | return nullptr; | |||
4705 | RD = Base; | |||
4706 | } | |||
4707 | // Finally cast to the class containing the member. | |||
4708 | if (!HandleLValueDirectBase(Info, RHS, LV, RD, | |||
4709 | MemPtr.getContainingRecord())) | |||
4710 | return nullptr; | |||
4711 | } | |||
4712 | ||||
4713 | // Add the member. Note that we cannot build bound member functions here. | |||
4714 | if (IncludeMember) { | |||
4715 | if (const FieldDecl *FD = dyn_cast<FieldDecl>(MemPtr.getDecl())) { | |||
4716 | if (!HandleLValueMember(Info, RHS, LV, FD)) | |||
4717 | return nullptr; | |||
4718 | } else if (const IndirectFieldDecl *IFD = | |||
4719 | dyn_cast<IndirectFieldDecl>(MemPtr.getDecl())) { | |||
4720 | if (!HandleLValueIndirectMember(Info, RHS, LV, IFD)) | |||
4721 | return nullptr; | |||
4722 | } else { | |||
4723 | llvm_unreachable("can't construct reference to bound member function")::llvm::llvm_unreachable_internal("can't construct reference to bound member function" , "clang/lib/AST/ExprConstant.cpp", 4723); | |||
4724 | } | |||
4725 | } | |||
4726 | ||||
4727 | return MemPtr.getDecl(); | |||
4728 | } | |||
4729 | ||||
4730 | static const ValueDecl *HandleMemberPointerAccess(EvalInfo &Info, | |||
4731 | const BinaryOperator *BO, | |||
4732 | LValue &LV, | |||
4733 | bool IncludeMember = true) { | |||
4734 | assert(BO->getOpcode() == BO_PtrMemD || BO->getOpcode() == BO_PtrMemI)(static_cast <bool> (BO->getOpcode() == BO_PtrMemD || BO->getOpcode() == BO_PtrMemI) ? void (0) : __assert_fail ("BO->getOpcode() == BO_PtrMemD || BO->getOpcode() == BO_PtrMemI" , "clang/lib/AST/ExprConstant.cpp", 4734, __extension__ __PRETTY_FUNCTION__ )); | |||
4735 | ||||
4736 | if (!EvaluateObjectArgument(Info, BO->getLHS(), LV)) { | |||
4737 | if (Info.noteFailure()) { | |||
4738 | MemberPtr MemPtr; | |||
4739 | EvaluateMemberPointer(BO->getRHS(), MemPtr, Info); | |||
4740 | } | |||
4741 | return nullptr; | |||
4742 | } | |||
4743 | ||||
4744 | return HandleMemberPointerAccess(Info, BO->getLHS()->getType(), LV, | |||
4745 | BO->getRHS(), IncludeMember); | |||
4746 | } | |||
4747 | ||||
4748 | /// HandleBaseToDerivedCast - Apply the given base-to-derived cast operation on | |||
4749 | /// the provided lvalue, which currently refers to the base object. | |||
4750 | static bool HandleBaseToDerivedCast(EvalInfo &Info, const CastExpr *E, | |||
4751 | LValue &Result) { | |||
4752 | SubobjectDesignator &D = Result.Designator; | |||
4753 | if (D.Invalid || !Result.checkNullPointer(Info, E, CSK_Derived)) | |||
4754 | return false; | |||
4755 | ||||
4756 | QualType TargetQT = E->getType(); | |||
4757 | if (const PointerType *PT = TargetQT->getAs<PointerType>()) | |||
4758 | TargetQT = PT->getPointeeType(); | |||
4759 | ||||
4760 | // Check this cast lands within the final derived-to-base subobject path. | |||
4761 | if (D.MostDerivedPathLength + E->path_size() > D.Entries.size()) { | |||
4762 | Info.CCEDiag(E, diag::note_constexpr_invalid_downcast) | |||
4763 | << D.MostDerivedType << TargetQT; | |||
4764 | return false; | |||
4765 | } | |||
4766 | ||||
4767 | // Check the type of the final cast. We don't need to check the path, | |||
4768 | // since a cast can only be formed if the path is unique. | |||
4769 | unsigned NewEntriesSize = D.Entries.size() - E->path_size(); | |||
4770 | const CXXRecordDecl *TargetType = TargetQT->getAsCXXRecordDecl(); | |||
4771 | const CXXRecordDecl *FinalType; | |||
4772 | if (NewEntriesSize == D.MostDerivedPathLength) | |||
4773 | FinalType = D.MostDerivedType->getAsCXXRecordDecl(); | |||
4774 | else | |||
4775 | FinalType = getAsBaseClass(D.Entries[NewEntriesSize - 1]); | |||
4776 | if (FinalType->getCanonicalDecl() != TargetType->getCanonicalDecl()) { | |||
4777 | Info.CCEDiag(E, diag::note_constexpr_invalid_downcast) | |||
4778 | << D.MostDerivedType << TargetQT; | |||
4779 | return false; | |||
4780 | } | |||
4781 | ||||
4782 | // Truncate the lvalue to the appropriate derived class. | |||
4783 | return CastToDerivedClass(Info, E, Result, TargetType, NewEntriesSize); | |||
4784 | } | |||
4785 | ||||
4786 | /// Get the value to use for a default-initialized object of type T. | |||
4787 | /// Return false if it encounters something invalid. | |||
4788 | static bool getDefaultInitValue(QualType T, APValue &Result) { | |||
4789 | bool Success = true; | |||
4790 | if (auto *RD = T->getAsCXXRecordDecl()) { | |||
4791 | if (RD->isInvalidDecl()) { | |||
4792 | Result = APValue(); | |||
4793 | return false; | |||
4794 | } | |||
4795 | if (RD->isUnion()) { | |||
4796 | Result = APValue((const FieldDecl *)nullptr); | |||
4797 | return true; | |||
4798 | } | |||
4799 | Result = APValue(APValue::UninitStruct(), RD->getNumBases(), | |||
4800 | std::distance(RD->field_begin(), RD->field_end())); | |||
4801 | ||||
4802 | unsigned Index = 0; | |||
4803 | for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(), | |||
4804 | End = RD->bases_end(); | |||
4805 | I != End; ++I, ++Index) | |||
4806 | Success &= getDefaultInitValue(I->getType(), Result.getStructBase(Index)); | |||
4807 | ||||
4808 | for (const auto *I : RD->fields()) { | |||
4809 | if (I->isUnnamedBitfield()) | |||
4810 | continue; | |||
4811 | Success &= getDefaultInitValue(I->getType(), | |||
4812 | Result.getStructField(I->getFieldIndex())); | |||
4813 | } | |||
4814 | return Success; | |||
4815 | } | |||
4816 | ||||
4817 | if (auto *AT = | |||
4818 | dyn_cast_or_null<ConstantArrayType>(T->getAsArrayTypeUnsafe())) { | |||
4819 | Result = APValue(APValue::UninitArray(), 0, AT->getSize().getZExtValue()); | |||
4820 | if (Result.hasArrayFiller()) | |||
4821 | Success &= | |||
4822 | getDefaultInitValue(AT->getElementType(), Result.getArrayFiller()); | |||
4823 | ||||
4824 | return Success; | |||
4825 | } | |||
4826 | ||||
4827 | Result = APValue::IndeterminateValue(); | |||
4828 | return true; | |||
4829 | } | |||
4830 | ||||
4831 | namespace { | |||
4832 | enum EvalStmtResult { | |||
4833 | /// Evaluation failed. | |||
4834 | ESR_Failed, | |||
4835 | /// Hit a 'return' statement. | |||
4836 | ESR_Returned, | |||
4837 | /// Evaluation succeeded. | |||
4838 | ESR_Succeeded, | |||
4839 | /// Hit a 'continue' statement. | |||
4840 | ESR_Continue, | |||
4841 | /// Hit a 'break' statement. | |||
4842 | ESR_Break, | |||
4843 | /// Still scanning for 'case' or 'default' statement. | |||
4844 | ESR_CaseNotFound | |||
4845 | }; | |||
4846 | } | |||
4847 | ||||
4848 | static bool EvaluateVarDecl(EvalInfo &Info, const VarDecl *VD) { | |||
4849 | if (VD->isInvalidDecl()) | |||
4850 | return false; | |||
4851 | // We don't need to evaluate the initializer for a static local. | |||
4852 | if (!VD->hasLocalStorage()) | |||
4853 | return true; | |||
4854 | ||||
4855 | LValue Result; | |||
4856 | APValue &Val = Info.CurrentCall->createTemporary(VD, VD->getType(), | |||
4857 | ScopeKind::Block, Result); | |||
4858 | ||||
4859 | const Expr *InitE = VD->getInit(); | |||
4860 | if (!InitE) { | |||
4861 | if (VD->getType()->isDependentType()) | |||
4862 | return Info.noteSideEffect(); | |||
4863 | return getDefaultInitValue(VD->getType(), Val); | |||
4864 | } | |||
4865 | if (InitE->isValueDependent()) | |||
4866 | return false; | |||
4867 | ||||
4868 | if (!EvaluateInPlace(Val, Info, Result, InitE)) { | |||
4869 | // Wipe out any partially-computed value, to allow tracking that this | |||
4870 | // evaluation failed. | |||
4871 | Val = APValue(); | |||
4872 | return false; | |||
4873 | } | |||
4874 | ||||
4875 | return true; | |||
4876 | } | |||
4877 | ||||
4878 | static bool EvaluateDecl(EvalInfo &Info, const Decl *D) { | |||
4879 | bool OK = true; | |||
4880 | ||||
4881 | if (const VarDecl *VD = dyn_cast<VarDecl>(D)) | |||
4882 | OK &= EvaluateVarDecl(Info, VD); | |||
4883 | ||||
4884 | if (const DecompositionDecl *DD = dyn_cast<DecompositionDecl>(D)) | |||
4885 | for (auto *BD : DD->bindings()) | |||
4886 | if (auto *VD = BD->getHoldingVar()) | |||
4887 | OK &= EvaluateDecl(Info, VD); | |||
4888 | ||||
4889 | return OK; | |||
4890 | } | |||
4891 | ||||
4892 | static bool EvaluateDependentExpr(const Expr *E, EvalInfo &Info) { | |||
4893 | assert(E->isValueDependent())(static_cast <bool> (E->isValueDependent()) ? void ( 0) : __assert_fail ("E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 4893, __extension__ __PRETTY_FUNCTION__)); | |||
4894 | if (Info.noteSideEffect()) | |||
4895 | return true; | |||
4896 | assert(E->containsErrors() && "valid value-dependent expression should never "(static_cast <bool> (E->containsErrors() && "valid value-dependent expression should never " "reach invalid code path.") ? void (0) : __assert_fail ("E->containsErrors() && \"valid value-dependent expression should never \" \"reach invalid code path.\"" , "clang/lib/AST/ExprConstant.cpp", 4897, __extension__ __PRETTY_FUNCTION__ )) | |||
4897 | "reach invalid code path.")(static_cast <bool> (E->containsErrors() && "valid value-dependent expression should never " "reach invalid code path.") ? void (0) : __assert_fail ("E->containsErrors() && \"valid value-dependent expression should never \" \"reach invalid code path.\"" , "clang/lib/AST/ExprConstant.cpp", 4897, __extension__ __PRETTY_FUNCTION__ )); | |||
4898 | return false; | |||
4899 | } | |||
4900 | ||||
4901 | /// Evaluate a condition (either a variable declaration or an expression). | |||
4902 | static bool EvaluateCond(EvalInfo &Info, const VarDecl *CondDecl, | |||
4903 | const Expr *Cond, bool &Result) { | |||
4904 | if (Cond->isValueDependent()) | |||
4905 | return false; | |||
4906 | FullExpressionRAII Scope(Info); | |||
4907 | if (CondDecl && !EvaluateDecl(Info, CondDecl)) | |||
4908 | return false; | |||
4909 | if (!EvaluateAsBooleanCondition(Cond, Result, Info)) | |||
4910 | return false; | |||
4911 | return Scope.destroy(); | |||
4912 | } | |||
4913 | ||||
4914 | namespace { | |||
4915 | /// A location where the result (returned value) of evaluating a | |||
4916 | /// statement should be stored. | |||
4917 | struct StmtResult { | |||
4918 | /// The APValue that should be filled in with the returned value. | |||
4919 | APValue &Value; | |||
4920 | /// The location containing the result, if any (used to support RVO). | |||
4921 | const LValue *Slot; | |||
4922 | }; | |||
4923 | ||||
4924 | struct TempVersionRAII { | |||
4925 | CallStackFrame &Frame; | |||
4926 | ||||
4927 | TempVersionRAII(CallStackFrame &Frame) : Frame(Frame) { | |||
4928 | Frame.pushTempVersion(); | |||
4929 | } | |||
4930 | ||||
4931 | ~TempVersionRAII() { | |||
4932 | Frame.popTempVersion(); | |||
4933 | } | |||
4934 | }; | |||
4935 | ||||
4936 | } | |||
4937 | ||||
4938 | static EvalStmtResult EvaluateStmt(StmtResult &Result, EvalInfo &Info, | |||
4939 | const Stmt *S, | |||
4940 | const SwitchCase *SC = nullptr); | |||
4941 | ||||
4942 | /// Evaluate the body of a loop, and translate the result as appropriate. | |||
4943 | static EvalStmtResult EvaluateLoopBody(StmtResult &Result, EvalInfo &Info, | |||
4944 | const Stmt *Body, | |||
4945 | const SwitchCase *Case = nullptr) { | |||
4946 | BlockScopeRAII Scope(Info); | |||
4947 | ||||
4948 | EvalStmtResult ESR = EvaluateStmt(Result, Info, Body, Case); | |||
4949 | if (ESR != ESR_Failed && ESR != ESR_CaseNotFound && !Scope.destroy()) | |||
4950 | ESR = ESR_Failed; | |||
4951 | ||||
4952 | switch (ESR) { | |||
4953 | case ESR_Break: | |||
4954 | return ESR_Succeeded; | |||
4955 | case ESR_Succeeded: | |||
4956 | case ESR_Continue: | |||
4957 | return ESR_Continue; | |||
4958 | case ESR_Failed: | |||
4959 | case ESR_Returned: | |||
4960 | case ESR_CaseNotFound: | |||
4961 | return ESR; | |||
4962 | } | |||
4963 | llvm_unreachable("Invalid EvalStmtResult!")::llvm::llvm_unreachable_internal("Invalid EvalStmtResult!", "clang/lib/AST/ExprConstant.cpp" , 4963); | |||
4964 | } | |||
4965 | ||||
4966 | /// Evaluate a switch statement. | |||
4967 | static EvalStmtResult EvaluateSwitch(StmtResult &Result, EvalInfo &Info, | |||
4968 | const SwitchStmt *SS) { | |||
4969 | BlockScopeRAII Scope(Info); | |||
4970 | ||||
4971 | // Evaluate the switch condition. | |||
4972 | APSInt Value; | |||
4973 | { | |||
4974 | if (const Stmt *Init = SS->getInit()) { | |||
4975 | EvalStmtResult ESR = EvaluateStmt(Result, Info, Init); | |||
4976 | if (ESR != ESR_Succeeded) { | |||
4977 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
4978 | ESR = ESR_Failed; | |||
4979 | return ESR; | |||
4980 | } | |||
4981 | } | |||
4982 | ||||
4983 | FullExpressionRAII CondScope(Info); | |||
4984 | if (SS->getConditionVariable() && | |||
4985 | !EvaluateDecl(Info, SS->getConditionVariable())) | |||
4986 | return ESR_Failed; | |||
4987 | if (SS->getCond()->isValueDependent()) { | |||
4988 | if (!EvaluateDependentExpr(SS->getCond(), Info)) | |||
4989 | return ESR_Failed; | |||
4990 | } else { | |||
4991 | if (!EvaluateInteger(SS->getCond(), Value, Info)) | |||
4992 | return ESR_Failed; | |||
4993 | } | |||
4994 | if (!CondScope.destroy()) | |||
4995 | return ESR_Failed; | |||
4996 | } | |||
4997 | ||||
4998 | // Find the switch case corresponding to the value of the condition. | |||
4999 | // FIXME: Cache this lookup. | |||
5000 | const SwitchCase *Found = nullptr; | |||
5001 | for (const SwitchCase *SC = SS->getSwitchCaseList(); SC; | |||
5002 | SC = SC->getNextSwitchCase()) { | |||
5003 | if (isa<DefaultStmt>(SC)) { | |||
5004 | Found = SC; | |||
5005 | continue; | |||
5006 | } | |||
5007 | ||||
5008 | const CaseStmt *CS = cast<CaseStmt>(SC); | |||
5009 | APSInt LHS = CS->getLHS()->EvaluateKnownConstInt(Info.Ctx); | |||
5010 | APSInt RHS = CS->getRHS() ? CS->getRHS()->EvaluateKnownConstInt(Info.Ctx) | |||
5011 | : LHS; | |||
5012 | if (LHS <= Value && Value <= RHS) { | |||
5013 | Found = SC; | |||
5014 | break; | |||
5015 | } | |||
5016 | } | |||
5017 | ||||
5018 | if (!Found) | |||
5019 | return Scope.destroy() ? ESR_Succeeded : ESR_Failed; | |||
5020 | ||||
5021 | // Search the switch body for the switch case and evaluate it from there. | |||
5022 | EvalStmtResult ESR = EvaluateStmt(Result, Info, SS->getBody(), Found); | |||
5023 | if (ESR != ESR_Failed && ESR != ESR_CaseNotFound && !Scope.destroy()) | |||
5024 | return ESR_Failed; | |||
5025 | ||||
5026 | switch (ESR) { | |||
5027 | case ESR_Break: | |||
5028 | return ESR_Succeeded; | |||
5029 | case ESR_Succeeded: | |||
5030 | case ESR_Continue: | |||
5031 | case ESR_Failed: | |||
5032 | case ESR_Returned: | |||
5033 | return ESR; | |||
5034 | case ESR_CaseNotFound: | |||
5035 | // This can only happen if the switch case is nested within a statement | |||
5036 | // expression. We have no intention of supporting that. | |||
5037 | Info.FFDiag(Found->getBeginLoc(), | |||
5038 | diag::note_constexpr_stmt_expr_unsupported); | |||
5039 | return ESR_Failed; | |||
5040 | } | |||
5041 | llvm_unreachable("Invalid EvalStmtResult!")::llvm::llvm_unreachable_internal("Invalid EvalStmtResult!", "clang/lib/AST/ExprConstant.cpp" , 5041); | |||
5042 | } | |||
5043 | ||||
5044 | static bool CheckLocalVariableDeclaration(EvalInfo &Info, const VarDecl *VD) { | |||
5045 | // An expression E is a core constant expression unless the evaluation of E | |||
5046 | // would evaluate one of the following: [C++23] - a control flow that passes | |||
5047 | // through a declaration of a variable with static or thread storage duration | |||
5048 | // unless that variable is usable in constant expressions. | |||
5049 | if (VD->isLocalVarDecl() && VD->isStaticLocal() && | |||
5050 | !VD->isUsableInConstantExpressions(Info.Ctx)) { | |||
5051 | Info.CCEDiag(VD->getLocation(), diag::note_constexpr_static_local) | |||
5052 | << (VD->getTSCSpec() == TSCS_unspecified ? 0 : 1) << VD; | |||
5053 | return false; | |||
5054 | } | |||
5055 | return true; | |||
5056 | } | |||
5057 | ||||
5058 | // Evaluate a statement. | |||
5059 | static EvalStmtResult EvaluateStmt(StmtResult &Result, EvalInfo &Info, | |||
5060 | const Stmt *S, const SwitchCase *Case) { | |||
5061 | if (!Info.nextStep(S)) | |||
5062 | return ESR_Failed; | |||
5063 | ||||
5064 | // If we're hunting down a 'case' or 'default' label, recurse through | |||
5065 | // substatements until we hit the label. | |||
5066 | if (Case) { | |||
5067 | switch (S->getStmtClass()) { | |||
5068 | case Stmt::CompoundStmtClass: | |||
5069 | // FIXME: Precompute which substatement of a compound statement we | |||
5070 | // would jump to, and go straight there rather than performing a | |||
5071 | // linear scan each time. | |||
5072 | case Stmt::LabelStmtClass: | |||
5073 | case Stmt::AttributedStmtClass: | |||
5074 | case Stmt::DoStmtClass: | |||
5075 | break; | |||
5076 | ||||
5077 | case Stmt::CaseStmtClass: | |||
5078 | case Stmt::DefaultStmtClass: | |||
5079 | if (Case == S) | |||
5080 | Case = nullptr; | |||
5081 | break; | |||
5082 | ||||
5083 | case Stmt::IfStmtClass: { | |||
5084 | // FIXME: Precompute which side of an 'if' we would jump to, and go | |||
5085 | // straight there rather than scanning both sides. | |||
5086 | const IfStmt *IS = cast<IfStmt>(S); | |||
5087 | ||||
5088 | // Wrap the evaluation in a block scope, in case it's a DeclStmt | |||
5089 | // preceded by our switch label. | |||
5090 | BlockScopeRAII Scope(Info); | |||
5091 | ||||
5092 | // Step into the init statement in case it brings an (uninitialized) | |||
5093 | // variable into scope. | |||
5094 | if (const Stmt *Init = IS->getInit()) { | |||
5095 | EvalStmtResult ESR = EvaluateStmt(Result, Info, Init, Case); | |||
5096 | if (ESR != ESR_CaseNotFound) { | |||
5097 | assert(ESR != ESR_Succeeded)(static_cast <bool> (ESR != ESR_Succeeded) ? void (0) : __assert_fail ("ESR != ESR_Succeeded", "clang/lib/AST/ExprConstant.cpp" , 5097, __extension__ __PRETTY_FUNCTION__)); | |||
5098 | return ESR; | |||
5099 | } | |||
5100 | } | |||
5101 | ||||
5102 | // Condition variable must be initialized if it exists. | |||
5103 | // FIXME: We can skip evaluating the body if there's a condition | |||
5104 | // variable, as there can't be any case labels within it. | |||
5105 | // (The same is true for 'for' statements.) | |||
5106 | ||||
5107 | EvalStmtResult ESR = EvaluateStmt(Result, Info, IS->getThen(), Case); | |||
5108 | if (ESR == ESR_Failed) | |||
5109 | return ESR; | |||
5110 | if (ESR != ESR_CaseNotFound) | |||
5111 | return Scope.destroy() ? ESR : ESR_Failed; | |||
5112 | if (!IS->getElse()) | |||
5113 | return ESR_CaseNotFound; | |||
5114 | ||||
5115 | ESR = EvaluateStmt(Result, Info, IS->getElse(), Case); | |||
5116 | if (ESR == ESR_Failed) | |||
5117 | return ESR; | |||
5118 | if (ESR != ESR_CaseNotFound) | |||
5119 | return Scope.destroy() ? ESR : ESR_Failed; | |||
5120 | return ESR_CaseNotFound; | |||
5121 | } | |||
5122 | ||||
5123 | case Stmt::WhileStmtClass: { | |||
5124 | EvalStmtResult ESR = | |||
5125 | EvaluateLoopBody(Result, Info, cast<WhileStmt>(S)->getBody(), Case); | |||
5126 | if (ESR != ESR_Continue) | |||
5127 | return ESR; | |||
5128 | break; | |||
5129 | } | |||
5130 | ||||
5131 | case Stmt::ForStmtClass: { | |||
5132 | const ForStmt *FS = cast<ForStmt>(S); | |||
5133 | BlockScopeRAII Scope(Info); | |||
5134 | ||||
5135 | // Step into the init statement in case it brings an (uninitialized) | |||
5136 | // variable into scope. | |||
5137 | if (const Stmt *Init = FS->getInit()) { | |||
5138 | EvalStmtResult ESR = EvaluateStmt(Result, Info, Init, Case); | |||
5139 | if (ESR != ESR_CaseNotFound) { | |||
5140 | assert(ESR != ESR_Succeeded)(static_cast <bool> (ESR != ESR_Succeeded) ? void (0) : __assert_fail ("ESR != ESR_Succeeded", "clang/lib/AST/ExprConstant.cpp" , 5140, __extension__ __PRETTY_FUNCTION__)); | |||
5141 | return ESR; | |||
5142 | } | |||
5143 | } | |||
5144 | ||||
5145 | EvalStmtResult ESR = | |||
5146 | EvaluateLoopBody(Result, Info, FS->getBody(), Case); | |||
5147 | if (ESR != ESR_Continue) | |||
5148 | return ESR; | |||
5149 | if (const auto *Inc = FS->getInc()) { | |||
5150 | if (Inc->isValueDependent()) { | |||
5151 | if (!EvaluateDependentExpr(Inc, Info)) | |||
5152 | return ESR_Failed; | |||
5153 | } else { | |||
5154 | FullExpressionRAII IncScope(Info); | |||
5155 | if (!EvaluateIgnoredValue(Info, Inc) || !IncScope.destroy()) | |||
5156 | return ESR_Failed; | |||
5157 | } | |||
5158 | } | |||
5159 | break; | |||
5160 | } | |||
5161 | ||||
5162 | case Stmt::DeclStmtClass: { | |||
5163 | // Start the lifetime of any uninitialized variables we encounter. They | |||
5164 | // might be used by the selected branch of the switch. | |||
5165 | const DeclStmt *DS = cast<DeclStmt>(S); | |||
5166 | for (const auto *D : DS->decls()) { | |||
5167 | if (const auto *VD = dyn_cast<VarDecl>(D)) { | |||
5168 | if (!CheckLocalVariableDeclaration(Info, VD)) | |||
5169 | return ESR_Failed; | |||
5170 | if (VD->hasLocalStorage() && !VD->getInit()) | |||
5171 | if (!EvaluateVarDecl(Info, VD)) | |||
5172 | return ESR_Failed; | |||
5173 | // FIXME: If the variable has initialization that can't be jumped | |||
5174 | // over, bail out of any immediately-surrounding compound-statement | |||
5175 | // too. There can't be any case labels here. | |||
5176 | } | |||
5177 | } | |||
5178 | return ESR_CaseNotFound; | |||
5179 | } | |||
5180 | ||||
5181 | default: | |||
5182 | return ESR_CaseNotFound; | |||
5183 | } | |||
5184 | } | |||
5185 | ||||
5186 | switch (S->getStmtClass()) { | |||
5187 | default: | |||
5188 | if (const Expr *E = dyn_cast<Expr>(S)) { | |||
5189 | if (E->isValueDependent()) { | |||
5190 | if (!EvaluateDependentExpr(E, Info)) | |||
5191 | return ESR_Failed; | |||
5192 | } else { | |||
5193 | // Don't bother evaluating beyond an expression-statement which couldn't | |||
5194 | // be evaluated. | |||
5195 | // FIXME: Do we need the FullExpressionRAII object here? | |||
5196 | // VisitExprWithCleanups should create one when necessary. | |||
5197 | FullExpressionRAII Scope(Info); | |||
5198 | if (!EvaluateIgnoredValue(Info, E) || !Scope.destroy()) | |||
5199 | return ESR_Failed; | |||
5200 | } | |||
5201 | return ESR_Succeeded; | |||
5202 | } | |||
5203 | ||||
5204 | Info.FFDiag(S->getBeginLoc()); | |||
5205 | return ESR_Failed; | |||
5206 | ||||
5207 | case Stmt::NullStmtClass: | |||
5208 | return ESR_Succeeded; | |||
5209 | ||||
5210 | case Stmt::DeclStmtClass: { | |||
5211 | const DeclStmt *DS = cast<DeclStmt>(S); | |||
5212 | for (const auto *D : DS->decls()) { | |||
5213 | const VarDecl *VD = dyn_cast_or_null<VarDecl>(D); | |||
5214 | if (VD && !CheckLocalVariableDeclaration(Info, VD)) | |||
5215 | return ESR_Failed; | |||
5216 | // Each declaration initialization is its own full-expression. | |||
5217 | FullExpressionRAII Scope(Info); | |||
5218 | if (!EvaluateDecl(Info, D) && !Info.noteFailure()) | |||
5219 | return ESR_Failed; | |||
5220 | if (!Scope.destroy()) | |||
5221 | return ESR_Failed; | |||
5222 | } | |||
5223 | return ESR_Succeeded; | |||
5224 | } | |||
5225 | ||||
5226 | case Stmt::ReturnStmtClass: { | |||
5227 | const Expr *RetExpr = cast<ReturnStmt>(S)->getRetValue(); | |||
5228 | FullExpressionRAII Scope(Info); | |||
5229 | if (RetExpr && RetExpr->isValueDependent()) { | |||
5230 | EvaluateDependentExpr(RetExpr, Info); | |||
5231 | // We know we returned, but we don't know what the value is. | |||
5232 | return ESR_Failed; | |||
5233 | } | |||
5234 | if (RetExpr && | |||
5235 | !(Result.Slot | |||
5236 | ? EvaluateInPlace(Result.Value, Info, *Result.Slot, RetExpr) | |||
5237 | : Evaluate(Result.Value, Info, RetExpr))) | |||
5238 | return ESR_Failed; | |||
5239 | return Scope.destroy() ? ESR_Returned : ESR_Failed; | |||
5240 | } | |||
5241 | ||||
5242 | case Stmt::CompoundStmtClass: { | |||
5243 | BlockScopeRAII Scope(Info); | |||
5244 | ||||
5245 | const CompoundStmt *CS = cast<CompoundStmt>(S); | |||
5246 | for (const auto *BI : CS->body()) { | |||
5247 | EvalStmtResult ESR = EvaluateStmt(Result, Info, BI, Case); | |||
5248 | if (ESR == ESR_Succeeded) | |||
5249 | Case = nullptr; | |||
5250 | else if (ESR != ESR_CaseNotFound) { | |||
5251 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
5252 | return ESR_Failed; | |||
5253 | return ESR; | |||
5254 | } | |||
5255 | } | |||
5256 | if (Case) | |||
5257 | return ESR_CaseNotFound; | |||
5258 | return Scope.destroy() ? ESR_Succeeded : ESR_Failed; | |||
5259 | } | |||
5260 | ||||
5261 | case Stmt::IfStmtClass: { | |||
5262 | const IfStmt *IS = cast<IfStmt>(S); | |||
5263 | ||||
5264 | // Evaluate the condition, as either a var decl or as an expression. | |||
5265 | BlockScopeRAII Scope(Info); | |||
5266 | if (const Stmt *Init = IS->getInit()) { | |||
5267 | EvalStmtResult ESR = EvaluateStmt(Result, Info, Init); | |||
5268 | if (ESR != ESR_Succeeded) { | |||
5269 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
5270 | return ESR_Failed; | |||
5271 | return ESR; | |||
5272 | } | |||
5273 | } | |||
5274 | bool Cond; | |||
5275 | if (IS->isConsteval()) { | |||
5276 | Cond = IS->isNonNegatedConsteval(); | |||
5277 | // If we are not in a constant context, if consteval should not evaluate | |||
5278 | // to true. | |||
5279 | if (!Info.InConstantContext) | |||
5280 | Cond = !Cond; | |||
5281 | } else if (!EvaluateCond(Info, IS->getConditionVariable(), IS->getCond(), | |||
5282 | Cond)) | |||
5283 | return ESR_Failed; | |||
5284 | ||||
5285 | if (const Stmt *SubStmt = Cond ? IS->getThen() : IS->getElse()) { | |||
5286 | EvalStmtResult ESR = EvaluateStmt(Result, Info, SubStmt); | |||
5287 | if (ESR != ESR_Succeeded) { | |||
5288 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
5289 | return ESR_Failed; | |||
5290 | return ESR; | |||
5291 | } | |||
5292 | } | |||
5293 | return Scope.destroy() ? ESR_Succeeded : ESR_Failed; | |||
5294 | } | |||
5295 | ||||
5296 | case Stmt::WhileStmtClass: { | |||
5297 | const WhileStmt *WS = cast<WhileStmt>(S); | |||
5298 | while (true) { | |||
5299 | BlockScopeRAII Scope(Info); | |||
5300 | bool Continue; | |||
5301 | if (!EvaluateCond(Info, WS->getConditionVariable(), WS->getCond(), | |||
5302 | Continue)) | |||
5303 | return ESR_Failed; | |||
5304 | if (!Continue) | |||
5305 | break; | |||
5306 | ||||
5307 | EvalStmtResult ESR = EvaluateLoopBody(Result, Info, WS->getBody()); | |||
5308 | if (ESR != ESR_Continue) { | |||
5309 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
5310 | return ESR_Failed; | |||
5311 | return ESR; | |||
5312 | } | |||
5313 | if (!Scope.destroy()) | |||
5314 | return ESR_Failed; | |||
5315 | } | |||
5316 | return ESR_Succeeded; | |||
5317 | } | |||
5318 | ||||
5319 | case Stmt::DoStmtClass: { | |||
5320 | const DoStmt *DS = cast<DoStmt>(S); | |||
5321 | bool Continue; | |||
5322 | do { | |||
5323 | EvalStmtResult ESR = EvaluateLoopBody(Result, Info, DS->getBody(), Case); | |||
5324 | if (ESR != ESR_Continue) | |||
5325 | return ESR; | |||
5326 | Case = nullptr; | |||
5327 | ||||
5328 | if (DS->getCond()->isValueDependent()) { | |||
5329 | EvaluateDependentExpr(DS->getCond(), Info); | |||
5330 | // Bailout as we don't know whether to keep going or terminate the loop. | |||
5331 | return ESR_Failed; | |||
5332 | } | |||
5333 | FullExpressionRAII CondScope(Info); | |||
5334 | if (!EvaluateAsBooleanCondition(DS->getCond(), Continue, Info) || | |||
5335 | !CondScope.destroy()) | |||
5336 | return ESR_Failed; | |||
5337 | } while (Continue); | |||
5338 | return ESR_Succeeded; | |||
5339 | } | |||
5340 | ||||
5341 | case Stmt::ForStmtClass: { | |||
5342 | const ForStmt *FS = cast<ForStmt>(S); | |||
5343 | BlockScopeRAII ForScope(Info); | |||
5344 | if (FS->getInit()) { | |||
5345 | EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getInit()); | |||
5346 | if (ESR != ESR_Succeeded) { | |||
5347 | if (ESR != ESR_Failed && !ForScope.destroy()) | |||
5348 | return ESR_Failed; | |||
5349 | return ESR; | |||
5350 | } | |||
5351 | } | |||
5352 | while (true) { | |||
5353 | BlockScopeRAII IterScope(Info); | |||
5354 | bool Continue = true; | |||
5355 | if (FS->getCond() && !EvaluateCond(Info, FS->getConditionVariable(), | |||
5356 | FS->getCond(), Continue)) | |||
5357 | return ESR_Failed; | |||
5358 | if (!Continue) | |||
5359 | break; | |||
5360 | ||||
5361 | EvalStmtResult ESR = EvaluateLoopBody(Result, Info, FS->getBody()); | |||
5362 | if (ESR != ESR_Continue) { | |||
5363 | if (ESR != ESR_Failed && (!IterScope.destroy() || !ForScope.destroy())) | |||
5364 | return ESR_Failed; | |||
5365 | return ESR; | |||
5366 | } | |||
5367 | ||||
5368 | if (const auto *Inc = FS->getInc()) { | |||
5369 | if (Inc->isValueDependent()) { | |||
5370 | if (!EvaluateDependentExpr(Inc, Info)) | |||
5371 | return ESR_Failed; | |||
5372 | } else { | |||
5373 | FullExpressionRAII IncScope(Info); | |||
5374 | if (!EvaluateIgnoredValue(Info, Inc) || !IncScope.destroy()) | |||
5375 | return ESR_Failed; | |||
5376 | } | |||
5377 | } | |||
5378 | ||||
5379 | if (!IterScope.destroy()) | |||
5380 | return ESR_Failed; | |||
5381 | } | |||
5382 | return ForScope.destroy() ? ESR_Succeeded : ESR_Failed; | |||
5383 | } | |||
5384 | ||||
5385 | case Stmt::CXXForRangeStmtClass: { | |||
5386 | const CXXForRangeStmt *FS = cast<CXXForRangeStmt>(S); | |||
5387 | BlockScopeRAII Scope(Info); | |||
5388 | ||||
5389 | // Evaluate the init-statement if present. | |||
5390 | if (FS->getInit()) { | |||
5391 | EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getInit()); | |||
5392 | if (ESR != ESR_Succeeded) { | |||
5393 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
5394 | return ESR_Failed; | |||
5395 | return ESR; | |||
5396 | } | |||
5397 | } | |||
5398 | ||||
5399 | // Initialize the __range variable. | |||
5400 | EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getRangeStmt()); | |||
5401 | if (ESR != ESR_Succeeded) { | |||
5402 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
5403 | return ESR_Failed; | |||
5404 | return ESR; | |||
5405 | } | |||
5406 | ||||
5407 | // In error-recovery cases it's possible to get here even if we failed to | |||
5408 | // synthesize the __begin and __end variables. | |||
5409 | if (!FS->getBeginStmt() || !FS->getEndStmt() || !FS->getCond()) | |||
5410 | return ESR_Failed; | |||
5411 | ||||
5412 | // Create the __begin and __end iterators. | |||
5413 | ESR = EvaluateStmt(Result, Info, FS->getBeginStmt()); | |||
5414 | if (ESR != ESR_Succeeded) { | |||
5415 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
5416 | return ESR_Failed; | |||
5417 | return ESR; | |||
5418 | } | |||
5419 | ESR = EvaluateStmt(Result, Info, FS->getEndStmt()); | |||
5420 | if (ESR != ESR_Succeeded) { | |||
5421 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
5422 | return ESR_Failed; | |||
5423 | return ESR; | |||
5424 | } | |||
5425 | ||||
5426 | while (true) { | |||
5427 | // Condition: __begin != __end. | |||
5428 | { | |||
5429 | if (FS->getCond()->isValueDependent()) { | |||
5430 | EvaluateDependentExpr(FS->getCond(), Info); | |||
5431 | // We don't know whether to keep going or terminate the loop. | |||
5432 | return ESR_Failed; | |||
5433 | } | |||
5434 | bool Continue = true; | |||
5435 | FullExpressionRAII CondExpr(Info); | |||
5436 | if (!EvaluateAsBooleanCondition(FS->getCond(), Continue, Info)) | |||
5437 | return ESR_Failed; | |||
5438 | if (!Continue) | |||
5439 | break; | |||
5440 | } | |||
5441 | ||||
5442 | // User's variable declaration, initialized by *__begin. | |||
5443 | BlockScopeRAII InnerScope(Info); | |||
5444 | ESR = EvaluateStmt(Result, Info, FS->getLoopVarStmt()); | |||
5445 | if (ESR != ESR_Succeeded) { | |||
5446 | if (ESR != ESR_Failed && (!InnerScope.destroy() || !Scope.destroy())) | |||
5447 | return ESR_Failed; | |||
5448 | return ESR; | |||
5449 | } | |||
5450 | ||||
5451 | // Loop body. | |||
5452 | ESR = EvaluateLoopBody(Result, Info, FS->getBody()); | |||
5453 | if (ESR != ESR_Continue) { | |||
5454 | if (ESR != ESR_Failed && (!InnerScope.destroy() || !Scope.destroy())) | |||
5455 | return ESR_Failed; | |||
5456 | return ESR; | |||
5457 | } | |||
5458 | if (FS->getInc()->isValueDependent()) { | |||
5459 | if (!EvaluateDependentExpr(FS->getInc(), Info)) | |||
5460 | return ESR_Failed; | |||
5461 | } else { | |||
5462 | // Increment: ++__begin | |||
5463 | if (!EvaluateIgnoredValue(Info, FS->getInc())) | |||
5464 | return ESR_Failed; | |||
5465 | } | |||
5466 | ||||
5467 | if (!InnerScope.destroy()) | |||
5468 | return ESR_Failed; | |||
5469 | } | |||
5470 | ||||
5471 | return Scope.destroy() ? ESR_Succeeded : ESR_Failed; | |||
5472 | } | |||
5473 | ||||
5474 | case Stmt::SwitchStmtClass: | |||
5475 | return EvaluateSwitch(Result, Info, cast<SwitchStmt>(S)); | |||
5476 | ||||
5477 | case Stmt::ContinueStmtClass: | |||
5478 | return ESR_Continue; | |||
5479 | ||||
5480 | case Stmt::BreakStmtClass: | |||
5481 | return ESR_Break; | |||
5482 | ||||
5483 | case Stmt::LabelStmtClass: | |||
5484 | return EvaluateStmt(Result, Info, cast<LabelStmt>(S)->getSubStmt(), Case); | |||
5485 | ||||
5486 | case Stmt::AttributedStmtClass: | |||
5487 | // As a general principle, C++11 attributes can be ignored without | |||
5488 | // any semantic impact. | |||
5489 | return EvaluateStmt(Result, Info, cast<AttributedStmt>(S)->getSubStmt(), | |||
5490 | Case); | |||
5491 | ||||
5492 | case Stmt::CaseStmtClass: | |||
5493 | case Stmt::DefaultStmtClass: | |||
5494 | return EvaluateStmt(Result, Info, cast<SwitchCase>(S)->getSubStmt(), Case); | |||
5495 | case Stmt::CXXTryStmtClass: | |||
5496 | // Evaluate try blocks by evaluating all sub statements. | |||
5497 | return EvaluateStmt(Result, Info, cast<CXXTryStmt>(S)->getTryBlock(), Case); | |||
5498 | } | |||
5499 | } | |||
5500 | ||||
5501 | /// CheckTrivialDefaultConstructor - Check whether a constructor is a trivial | |||
5502 | /// default constructor. If so, we'll fold it whether or not it's marked as | |||
5503 | /// constexpr. If it is marked as constexpr, we will never implicitly define it, | |||
5504 | /// so we need special handling. | |||
5505 | static bool CheckTrivialDefaultConstructor(EvalInfo &Info, SourceLocation Loc, | |||
5506 | const CXXConstructorDecl *CD, | |||
5507 | bool IsValueInitialization) { | |||
5508 | if (!CD->isTrivial() || !CD->isDefaultConstructor()) | |||
5509 | return false; | |||
5510 | ||||
5511 | // Value-initialization does not call a trivial default constructor, so such a | |||
5512 | // call is a core constant expression whether or not the constructor is | |||
5513 | // constexpr. | |||
5514 | if (!CD->isConstexpr() && !IsValueInitialization) { | |||
5515 | if (Info.getLangOpts().CPlusPlus11) { | |||
5516 | // FIXME: If DiagDecl is an implicitly-declared special member function, | |||
5517 | // we should be much more explicit about why it's not constexpr. | |||
5518 | Info.CCEDiag(Loc, diag::note_constexpr_invalid_function, 1) | |||
5519 | << /*IsConstexpr*/0 << /*IsConstructor*/1 << CD; | |||
5520 | Info.Note(CD->getLocation(), diag::note_declared_at); | |||
5521 | } else { | |||
5522 | Info.CCEDiag(Loc, diag::note_invalid_subexpr_in_const_expr); | |||
5523 | } | |||
5524 | } | |||
5525 | return true; | |||
5526 | } | |||
5527 | ||||
5528 | /// CheckConstexprFunction - Check that a function can be called in a constant | |||
5529 | /// expression. | |||
5530 | static bool CheckConstexprFunction(EvalInfo &Info, SourceLocation CallLoc, | |||
5531 | const FunctionDecl *Declaration, | |||
5532 | const FunctionDecl *Definition, | |||
5533 | const Stmt *Body) { | |||
5534 | // Potential constant expressions can contain calls to declared, but not yet | |||
5535 | // defined, constexpr functions. | |||
5536 | if (Info.checkingPotentialConstantExpression() && !Definition && | |||
5537 | Declaration->isConstexpr()) | |||
5538 | return false; | |||
5539 | ||||
5540 | // Bail out if the function declaration itself is invalid. We will | |||
5541 | // have produced a relevant diagnostic while parsing it, so just | |||
5542 | // note the problematic sub-expression. | |||
5543 | if (Declaration->isInvalidDecl()) { | |||
5544 | Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr); | |||
5545 | return false; | |||
5546 | } | |||
5547 | ||||
5548 | // DR1872: An instantiated virtual constexpr function can't be called in a | |||
5549 | // constant expression (prior to C++20). We can still constant-fold such a | |||
5550 | // call. | |||
5551 | if (!Info.Ctx.getLangOpts().CPlusPlus20 && isa<CXXMethodDecl>(Declaration) && | |||
5552 | cast<CXXMethodDecl>(Declaration)->isVirtual()) | |||
5553 | Info.CCEDiag(CallLoc, diag::note_constexpr_virtual_call); | |||
5554 | ||||
5555 | if (Definition && Definition->isInvalidDecl()) { | |||
5556 | Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr); | |||
5557 | return false; | |||
5558 | } | |||
5559 | ||||
5560 | // Can we evaluate this function call? | |||
5561 | if (Definition && Definition->isConstexpr() && Body) | |||
5562 | return true; | |||
5563 | ||||
5564 | if (Info.getLangOpts().CPlusPlus11) { | |||
5565 | const FunctionDecl *DiagDecl = Definition ? Definition : Declaration; | |||
5566 | ||||
5567 | // If this function is not constexpr because it is an inherited | |||
5568 | // non-constexpr constructor, diagnose that directly. | |||
5569 | auto *CD = dyn_cast<CXXConstructorDecl>(DiagDecl); | |||
5570 | if (CD && CD->isInheritingConstructor()) { | |||
5571 | auto *Inherited = CD->getInheritedConstructor().getConstructor(); | |||
5572 | if (!Inherited->isConstexpr()) | |||
5573 | DiagDecl = CD = Inherited; | |||
5574 | } | |||
5575 | ||||
5576 | // FIXME: If DiagDecl is an implicitly-declared special member function | |||
5577 | // or an inheriting constructor, we should be much more explicit about why | |||
5578 | // it's not constexpr. | |||
5579 | if (CD && CD->isInheritingConstructor()) | |||
5580 | Info.FFDiag(CallLoc, diag::note_constexpr_invalid_inhctor, 1) | |||
5581 | << CD->getInheritedConstructor().getConstructor()->getParent(); | |||
5582 | else | |||
5583 | Info.FFDiag(CallLoc, diag::note_constexpr_invalid_function, 1) | |||
5584 | << DiagDecl->isConstexpr() << (bool)CD << DiagDecl; | |||
5585 | Info.Note(DiagDecl->getLocation(), diag::note_declared_at); | |||
5586 | } else { | |||
5587 | Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr); | |||
5588 | } | |||
5589 | return false; | |||
5590 | } | |||
5591 | ||||
5592 | namespace { | |||
5593 | struct CheckDynamicTypeHandler { | |||
5594 | AccessKinds AccessKind; | |||
5595 | typedef bool result_type; | |||
5596 | bool failed() { return false; } | |||
5597 | bool found(APValue &Subobj, QualType SubobjType) { return true; } | |||
5598 | bool found(APSInt &Value, QualType SubobjType) { return true; } | |||
5599 | bool found(APFloat &Value, QualType SubobjType) { return true; } | |||
5600 | }; | |||
5601 | } // end anonymous namespace | |||
5602 | ||||
5603 | /// Check that we can access the notional vptr of an object / determine its | |||
5604 | /// dynamic type. | |||
5605 | static bool checkDynamicType(EvalInfo &Info, const Expr *E, const LValue &This, | |||
5606 | AccessKinds AK, bool Polymorphic) { | |||
5607 | if (This.Designator.Invalid) | |||
5608 | return false; | |||
5609 | ||||
5610 | CompleteObject Obj = findCompleteObject(Info, E, AK, This, QualType()); | |||
5611 | ||||
5612 | if (!Obj) | |||
5613 | return false; | |||
5614 | ||||
5615 | if (!Obj.Value) { | |||
5616 | // The object is not usable in constant expressions, so we can't inspect | |||
5617 | // its value to see if it's in-lifetime or what the active union members | |||
5618 | // are. We can still check for a one-past-the-end lvalue. | |||
5619 | if (This.Designator.isOnePastTheEnd() || | |||
5620 | This.Designator.isMostDerivedAnUnsizedArray()) { | |||
5621 | Info.FFDiag(E, This.Designator.isOnePastTheEnd() | |||
5622 | ? diag::note_constexpr_access_past_end | |||
5623 | : diag::note_constexpr_access_unsized_array) | |||
5624 | << AK; | |||
5625 | return false; | |||
5626 | } else if (Polymorphic) { | |||
5627 | // Conservatively refuse to perform a polymorphic operation if we would | |||
5628 | // not be able to read a notional 'vptr' value. | |||
5629 | APValue Val; | |||
5630 | This.moveInto(Val); | |||
5631 | QualType StarThisType = | |||
5632 | Info.Ctx.getLValueReferenceType(This.Designator.getType(Info.Ctx)); | |||
5633 | Info.FFDiag(E, diag::note_constexpr_polymorphic_unknown_dynamic_type) | |||
5634 | << AK << Val.getAsString(Info.Ctx, StarThisType); | |||
5635 | return false; | |||
5636 | } | |||
5637 | return true; | |||
5638 | } | |||
5639 | ||||
5640 | CheckDynamicTypeHandler Handler{AK}; | |||
5641 | return Obj && findSubobject(Info, E, Obj, This.Designator, Handler); | |||
5642 | } | |||
5643 | ||||
5644 | /// Check that the pointee of the 'this' pointer in a member function call is | |||
5645 | /// either within its lifetime or in its period of construction or destruction. | |||
5646 | static bool | |||
5647 | checkNonVirtualMemberCallThisPointer(EvalInfo &Info, const Expr *E, | |||
5648 | const LValue &This, | |||
5649 | const CXXMethodDecl *NamedMember) { | |||
5650 | return checkDynamicType( | |||
5651 | Info, E, This, | |||
5652 | isa<CXXDestructorDecl>(NamedMember) ? AK_Destroy : AK_MemberCall, false); | |||
5653 | } | |||
5654 | ||||
5655 | struct DynamicType { | |||
5656 | /// The dynamic class type of the object. | |||
5657 | const CXXRecordDecl *Type; | |||
5658 | /// The corresponding path length in the lvalue. | |||
5659 | unsigned PathLength; | |||
5660 | }; | |||
5661 | ||||
5662 | static const CXXRecordDecl *getBaseClassType(SubobjectDesignator &Designator, | |||
5663 | unsigned PathLength) { | |||
5664 | assert(PathLength >= Designator.MostDerivedPathLength && PathLength <=(static_cast <bool> (PathLength >= Designator.MostDerivedPathLength && PathLength <= Designator.Entries.size() && "invalid path length") ? void (0) : __assert_fail ("PathLength >= Designator.MostDerivedPathLength && PathLength <= Designator.Entries.size() && \"invalid path length\"" , "clang/lib/AST/ExprConstant.cpp", 5665, __extension__ __PRETTY_FUNCTION__ )) | |||
5665 | Designator.Entries.size() && "invalid path length")(static_cast <bool> (PathLength >= Designator.MostDerivedPathLength && PathLength <= Designator.Entries.size() && "invalid path length") ? void (0) : __assert_fail ("PathLength >= Designator.MostDerivedPathLength && PathLength <= Designator.Entries.size() && \"invalid path length\"" , "clang/lib/AST/ExprConstant.cpp", 5665, __extension__ __PRETTY_FUNCTION__ )); | |||
5666 | return (PathLength == Designator.MostDerivedPathLength) | |||
5667 | ? Designator.MostDerivedType->getAsCXXRecordDecl() | |||
5668 | : getAsBaseClass(Designator.Entries[PathLength - 1]); | |||
5669 | } | |||
5670 | ||||
5671 | /// Determine the dynamic type of an object. | |||
5672 | static std::optional<DynamicType> ComputeDynamicType(EvalInfo &Info, | |||
5673 | const Expr *E, | |||
5674 | LValue &This, | |||
5675 | AccessKinds AK) { | |||
5676 | // If we don't have an lvalue denoting an object of class type, there is no | |||
5677 | // meaningful dynamic type. (We consider objects of non-class type to have no | |||
5678 | // dynamic type.) | |||
5679 | if (!checkDynamicType(Info, E, This, AK, true)) | |||
5680 | return std::nullopt; | |||
5681 | ||||
5682 | // Refuse to compute a dynamic type in the presence of virtual bases. This | |||
5683 | // shouldn't happen other than in constant-folding situations, since literal | |||
5684 | // types can't have virtual bases. | |||
5685 | // | |||
5686 | // Note that consumers of DynamicType assume that the type has no virtual | |||
5687 | // bases, and will need modifications if this restriction is relaxed. | |||
5688 | const CXXRecordDecl *Class = | |||
5689 | This.Designator.MostDerivedType->getAsCXXRecordDecl(); | |||
5690 | if (!Class || Class->getNumVBases()) { | |||
5691 | Info.FFDiag(E); | |||
5692 | return std::nullopt; | |||
5693 | } | |||
5694 | ||||
5695 | // FIXME: For very deep class hierarchies, it might be beneficial to use a | |||
5696 | // binary search here instead. But the overwhelmingly common case is that | |||
5697 | // we're not in the middle of a constructor, so it probably doesn't matter | |||
5698 | // in practice. | |||
5699 | ArrayRef<APValue::LValuePathEntry> Path = This.Designator.Entries; | |||
5700 | for (unsigned PathLength = This.Designator.MostDerivedPathLength; | |||
5701 | PathLength <= Path.size(); ++PathLength) { | |||
5702 | switch (Info.isEvaluatingCtorDtor(This.getLValueBase(), | |||
5703 | Path.slice(0, PathLength))) { | |||
5704 | case ConstructionPhase::Bases: | |||
5705 | case ConstructionPhase::DestroyingBases: | |||
5706 | // We're constructing or destroying a base class. This is not the dynamic | |||
5707 | // type. | |||
5708 | break; | |||
5709 | ||||
5710 | case ConstructionPhase::None: | |||
5711 | case ConstructionPhase::AfterBases: | |||
5712 | case ConstructionPhase::AfterFields: | |||
5713 | case ConstructionPhase::Destroying: | |||
5714 | // We've finished constructing the base classes and not yet started | |||
5715 | // destroying them again, so this is the dynamic type. | |||
5716 | return DynamicType{getBaseClassType(This.Designator, PathLength), | |||
5717 | PathLength}; | |||
5718 | } | |||
5719 | } | |||
5720 | ||||
5721 | // CWG issue 1517: we're constructing a base class of the object described by | |||
5722 | // 'This', so that object has not yet begun its period of construction and | |||
5723 | // any polymorphic operation on it results in undefined behavior. | |||
5724 | Info.FFDiag(E); | |||
5725 | return std::nullopt; | |||
5726 | } | |||
5727 | ||||
5728 | /// Perform virtual dispatch. | |||
5729 | static const CXXMethodDecl *HandleVirtualDispatch( | |||
5730 | EvalInfo &Info, const Expr *E, LValue &This, const CXXMethodDecl *Found, | |||
5731 | llvm::SmallVectorImpl<QualType> &CovariantAdjustmentPath) { | |||
5732 | std::optional<DynamicType> DynType = ComputeDynamicType( | |||
5733 | Info, E, This, | |||
5734 | isa<CXXDestructorDecl>(Found) ? AK_Destroy : AK_MemberCall); | |||
5735 | if (!DynType) | |||
5736 | return nullptr; | |||
5737 | ||||
5738 | // Find the final overrider. It must be declared in one of the classes on the | |||
5739 | // path from the dynamic type to the static type. | |||
5740 | // FIXME: If we ever allow literal types to have virtual base classes, that | |||
5741 | // won't be true. | |||
5742 | const CXXMethodDecl *Callee = Found; | |||
5743 | unsigned PathLength = DynType->PathLength; | |||
5744 | for (/**/; PathLength <= This.Designator.Entries.size(); ++PathLength) { | |||
5745 | const CXXRecordDecl *Class = getBaseClassType(This.Designator, PathLength); | |||
5746 | const CXXMethodDecl *Overrider = | |||
5747 | Found->getCorrespondingMethodDeclaredInClass(Class, false); | |||
5748 | if (Overrider) { | |||
5749 | Callee = Overrider; | |||
5750 | break; | |||
5751 | } | |||
5752 | } | |||
5753 | ||||
5754 | // C++2a [class.abstract]p6: | |||
5755 | // the effect of making a virtual call to a pure virtual function [...] is | |||
5756 | // undefined | |||
5757 | if (Callee->isPure()) { | |||
5758 | Info.FFDiag(E, diag::note_constexpr_pure_virtual_call, 1) << Callee; | |||
5759 | Info.Note(Callee->getLocation(), diag::note_declared_at); | |||
5760 | return nullptr; | |||
5761 | } | |||
5762 | ||||
5763 | // If necessary, walk the rest of the path to determine the sequence of | |||
5764 | // covariant adjustment steps to apply. | |||
5765 | if (!Info.Ctx.hasSameUnqualifiedType(Callee->getReturnType(), | |||
5766 | Found->getReturnType())) { | |||
5767 | CovariantAdjustmentPath.push_back(Callee->getReturnType()); | |||
5768 | for (unsigned CovariantPathLength = PathLength + 1; | |||
5769 | CovariantPathLength != This.Designator.Entries.size(); | |||
5770 | ++CovariantPathLength) { | |||
5771 | const CXXRecordDecl *NextClass = | |||
5772 | getBaseClassType(This.Designator, CovariantPathLength); | |||
5773 | const CXXMethodDecl *Next = | |||
5774 | Found->getCorrespondingMethodDeclaredInClass(NextClass, false); | |||
5775 | if (Next && !Info.Ctx.hasSameUnqualifiedType( | |||
5776 | Next->getReturnType(), CovariantAdjustmentPath.back())) | |||
5777 | CovariantAdjustmentPath.push_back(Next->getReturnType()); | |||
5778 | } | |||
5779 | if (!Info.Ctx.hasSameUnqualifiedType(Found->getReturnType(), | |||
5780 | CovariantAdjustmentPath.back())) | |||
5781 | CovariantAdjustmentPath.push_back(Found->getReturnType()); | |||
5782 | } | |||
5783 | ||||
5784 | // Perform 'this' adjustment. | |||
5785 | if (!CastToDerivedClass(Info, E, This, Callee->getParent(), PathLength)) | |||
5786 | return nullptr; | |||
5787 | ||||
5788 | return Callee; | |||
5789 | } | |||
5790 | ||||
5791 | /// Perform the adjustment from a value returned by a virtual function to | |||
5792 | /// a value of the statically expected type, which may be a pointer or | |||
5793 | /// reference to a base class of the returned type. | |||
5794 | static bool HandleCovariantReturnAdjustment(EvalInfo &Info, const Expr *E, | |||
5795 | APValue &Result, | |||
5796 | ArrayRef<QualType> Path) { | |||
5797 | assert(Result.isLValue() &&(static_cast <bool> (Result.isLValue() && "unexpected kind of APValue for covariant return" ) ? void (0) : __assert_fail ("Result.isLValue() && \"unexpected kind of APValue for covariant return\"" , "clang/lib/AST/ExprConstant.cpp", 5798, __extension__ __PRETTY_FUNCTION__ )) | |||
5798 | "unexpected kind of APValue for covariant return")(static_cast <bool> (Result.isLValue() && "unexpected kind of APValue for covariant return" ) ? void (0) : __assert_fail ("Result.isLValue() && \"unexpected kind of APValue for covariant return\"" , "clang/lib/AST/ExprConstant.cpp", 5798, __extension__ __PRETTY_FUNCTION__ )); | |||
5799 | if (Result.isNullPointer()) | |||
5800 | return true; | |||
5801 | ||||
5802 | LValue LVal; | |||
5803 | LVal.setFrom(Info.Ctx, Result); | |||
5804 | ||||
5805 | const CXXRecordDecl *OldClass = Path[0]->getPointeeCXXRecordDecl(); | |||
5806 | for (unsigned I = 1; I != Path.size(); ++I) { | |||
5807 | const CXXRecordDecl *NewClass = Path[I]->getPointeeCXXRecordDecl(); | |||
5808 | assert(OldClass && NewClass && "unexpected kind of covariant return")(static_cast <bool> (OldClass && NewClass && "unexpected kind of covariant return") ? void (0) : __assert_fail ("OldClass && NewClass && \"unexpected kind of covariant return\"" , "clang/lib/AST/ExprConstant.cpp", 5808, __extension__ __PRETTY_FUNCTION__ )); | |||
5809 | if (OldClass != NewClass && | |||
5810 | !CastToBaseClass(Info, E, LVal, OldClass, NewClass)) | |||
5811 | return false; | |||
5812 | OldClass = NewClass; | |||
5813 | } | |||
5814 | ||||
5815 | LVal.moveInto(Result); | |||
5816 | return true; | |||
5817 | } | |||
5818 | ||||
5819 | /// Determine whether \p Base, which is known to be a direct base class of | |||
5820 | /// \p Derived, is a public base class. | |||
5821 | static bool isBaseClassPublic(const CXXRecordDecl *Derived, | |||
5822 | const CXXRecordDecl *Base) { | |||
5823 | for (const CXXBaseSpecifier &BaseSpec : Derived->bases()) { | |||
5824 | auto *BaseClass = BaseSpec.getType()->getAsCXXRecordDecl(); | |||
5825 | if (BaseClass && declaresSameEntity(BaseClass, Base)) | |||
5826 | return BaseSpec.getAccessSpecifier() == AS_public; | |||
5827 | } | |||
5828 | llvm_unreachable("Base is not a direct base of Derived")::llvm::llvm_unreachable_internal("Base is not a direct base of Derived" , "clang/lib/AST/ExprConstant.cpp", 5828); | |||
5829 | } | |||
5830 | ||||
5831 | /// Apply the given dynamic cast operation on the provided lvalue. | |||
5832 | /// | |||
5833 | /// This implements the hard case of dynamic_cast, requiring a "runtime check" | |||
5834 | /// to find a suitable target subobject. | |||
5835 | static bool HandleDynamicCast(EvalInfo &Info, const ExplicitCastExpr *E, | |||
5836 | LValue &Ptr) { | |||
5837 | // We can't do anything with a non-symbolic pointer value. | |||
5838 | SubobjectDesignator &D = Ptr.Designator; | |||
5839 | if (D.Invalid) | |||
5840 | return false; | |||
5841 | ||||
5842 | // C++ [expr.dynamic.cast]p6: | |||
5843 | // If v is a null pointer value, the result is a null pointer value. | |||
5844 | if (Ptr.isNullPointer() && !E->isGLValue()) | |||
5845 | return true; | |||
5846 | ||||
5847 | // For all the other cases, we need the pointer to point to an object within | |||
5848 | // its lifetime / period of construction / destruction, and we need to know | |||
5849 | // its dynamic type. | |||
5850 | std::optional<DynamicType> DynType = | |||
5851 | ComputeDynamicType(Info, E, Ptr, AK_DynamicCast); | |||
5852 | if (!DynType) | |||
5853 | return false; | |||
5854 | ||||
5855 | // C++ [expr.dynamic.cast]p7: | |||
5856 | // If T is "pointer to cv void", then the result is a pointer to the most | |||
5857 | // derived object | |||
5858 | if (E->getType()->isVoidPointerType()) | |||
5859 | return CastToDerivedClass(Info, E, Ptr, DynType->Type, DynType->PathLength); | |||
5860 | ||||
5861 | const CXXRecordDecl *C = E->getTypeAsWritten()->getPointeeCXXRecordDecl(); | |||
5862 | assert(C && "dynamic_cast target is not void pointer nor class")(static_cast <bool> (C && "dynamic_cast target is not void pointer nor class" ) ? void (0) : __assert_fail ("C && \"dynamic_cast target is not void pointer nor class\"" , "clang/lib/AST/ExprConstant.cpp", 5862, __extension__ __PRETTY_FUNCTION__ )); | |||
5863 | CanQualType CQT = Info.Ctx.getCanonicalType(Info.Ctx.getRecordType(C)); | |||
5864 | ||||
5865 | auto RuntimeCheckFailed = [&] (CXXBasePaths *Paths) { | |||
5866 | // C++ [expr.dynamic.cast]p9: | |||
5867 | if (!E->isGLValue()) { | |||
5868 | // The value of a failed cast to pointer type is the null pointer value | |||
5869 | // of the required result type. | |||
5870 | Ptr.setNull(Info.Ctx, E->getType()); | |||
5871 | return true; | |||
5872 | } | |||
5873 | ||||
5874 | // A failed cast to reference type throws [...] std::bad_cast. | |||
5875 | unsigned DiagKind; | |||
5876 | if (!Paths && (declaresSameEntity(DynType->Type, C) || | |||
5877 | DynType->Type->isDerivedFrom(C))) | |||
5878 | DiagKind = 0; | |||
5879 | else if (!Paths || Paths->begin() == Paths->end()) | |||
5880 | DiagKind = 1; | |||
5881 | else if (Paths->isAmbiguous(CQT)) | |||
5882 | DiagKind = 2; | |||
5883 | else { | |||
5884 | assert(Paths->front().Access != AS_public && "why did the cast fail?")(static_cast <bool> (Paths->front().Access != AS_public && "why did the cast fail?") ? void (0) : __assert_fail ("Paths->front().Access != AS_public && \"why did the cast fail?\"" , "clang/lib/AST/ExprConstant.cpp", 5884, __extension__ __PRETTY_FUNCTION__ )); | |||
5885 | DiagKind = 3; | |||
5886 | } | |||
5887 | Info.FFDiag(E, diag::note_constexpr_dynamic_cast_to_reference_failed) | |||
5888 | << DiagKind << Ptr.Designator.getType(Info.Ctx) | |||
5889 | << Info.Ctx.getRecordType(DynType->Type) | |||
5890 | << E->getType().getUnqualifiedType(); | |||
5891 | return false; | |||
5892 | }; | |||
5893 | ||||
5894 | // Runtime check, phase 1: | |||
5895 | // Walk from the base subobject towards the derived object looking for the | |||
5896 | // target type. | |||
5897 | for (int PathLength = Ptr.Designator.Entries.size(); | |||
5898 | PathLength >= (int)DynType->PathLength; --PathLength) { | |||
5899 | const CXXRecordDecl *Class = getBaseClassType(Ptr.Designator, PathLength); | |||
5900 | if (declaresSameEntity(Class, C)) | |||
5901 | return CastToDerivedClass(Info, E, Ptr, Class, PathLength); | |||
5902 | // We can only walk across public inheritance edges. | |||
5903 | if (PathLength > (int)DynType->PathLength && | |||
5904 | !isBaseClassPublic(getBaseClassType(Ptr.Designator, PathLength - 1), | |||
5905 | Class)) | |||
5906 | return RuntimeCheckFailed(nullptr); | |||
5907 | } | |||
5908 | ||||
5909 | // Runtime check, phase 2: | |||
5910 | // Search the dynamic type for an unambiguous public base of type C. | |||
5911 | CXXBasePaths Paths(/*FindAmbiguities=*/true, | |||
5912 | /*RecordPaths=*/true, /*DetectVirtual=*/false); | |||
5913 | if (DynType->Type->isDerivedFrom(C, Paths) && !Paths.isAmbiguous(CQT) && | |||
5914 | Paths.front().Access == AS_public) { | |||
5915 | // Downcast to the dynamic type... | |||
5916 | if (!CastToDerivedClass(Info, E, Ptr, DynType->Type, DynType->PathLength)) | |||
5917 | return false; | |||
5918 | // ... then upcast to the chosen base class subobject. | |||
5919 | for (CXXBasePathElement &Elem : Paths.front()) | |||
5920 | if (!HandleLValueBase(Info, E, Ptr, Elem.Class, Elem.Base)) | |||
5921 | return false; | |||
5922 | return true; | |||
5923 | } | |||
5924 | ||||
5925 | // Otherwise, the runtime check fails. | |||
5926 | return RuntimeCheckFailed(&Paths); | |||
5927 | } | |||
5928 | ||||
5929 | namespace { | |||
5930 | struct StartLifetimeOfUnionMemberHandler { | |||
5931 | EvalInfo &Info; | |||
5932 | const Expr *LHSExpr; | |||
5933 | const FieldDecl *Field; | |||
5934 | bool DuringInit; | |||
5935 | bool Failed = false; | |||
5936 | static const AccessKinds AccessKind = AK_Assign; | |||
5937 | ||||
5938 | typedef bool result_type; | |||
5939 | bool failed() { return Failed; } | |||
5940 | bool found(APValue &Subobj, QualType SubobjType) { | |||
5941 | // We are supposed to perform no initialization but begin the lifetime of | |||
5942 | // the object. We interpret that as meaning to do what default | |||
5943 | // initialization of the object would do if all constructors involved were | |||
5944 | // trivial: | |||
5945 | // * All base, non-variant member, and array element subobjects' lifetimes | |||
5946 | // begin | |||
5947 | // * No variant members' lifetimes begin | |||
5948 | // * All scalar subobjects whose lifetimes begin have indeterminate values | |||
5949 | assert(SubobjType->isUnionType())(static_cast <bool> (SubobjType->isUnionType()) ? void (0) : __assert_fail ("SubobjType->isUnionType()", "clang/lib/AST/ExprConstant.cpp" , 5949, __extension__ __PRETTY_FUNCTION__)); | |||
5950 | if (declaresSameEntity(Subobj.getUnionField(), Field)) { | |||
5951 | // This union member is already active. If it's also in-lifetime, there's | |||
5952 | // nothing to do. | |||
5953 | if (Subobj.getUnionValue().hasValue()) | |||
5954 | return true; | |||
5955 | } else if (DuringInit) { | |||
5956 | // We're currently in the process of initializing a different union | |||
5957 | // member. If we carried on, that initialization would attempt to | |||
5958 | // store to an inactive union member, resulting in undefined behavior. | |||
5959 | Info.FFDiag(LHSExpr, | |||
5960 | diag::note_constexpr_union_member_change_during_init); | |||
5961 | return false; | |||
5962 | } | |||
5963 | APValue Result; | |||
5964 | Failed = !getDefaultInitValue(Field->getType(), Result); | |||
5965 | Subobj.setUnion(Field, Result); | |||
5966 | return true; | |||
5967 | } | |||
5968 | bool found(APSInt &Value, QualType SubobjType) { | |||
5969 | llvm_unreachable("wrong value kind for union object")::llvm::llvm_unreachable_internal("wrong value kind for union object" , "clang/lib/AST/ExprConstant.cpp", 5969); | |||
5970 | } | |||
5971 | bool found(APFloat &Value, QualType SubobjType) { | |||
5972 | llvm_unreachable("wrong value kind for union object")::llvm::llvm_unreachable_internal("wrong value kind for union object" , "clang/lib/AST/ExprConstant.cpp", 5972); | |||
5973 | } | |||
5974 | }; | |||
5975 | } // end anonymous namespace | |||
5976 | ||||
5977 | const AccessKinds StartLifetimeOfUnionMemberHandler::AccessKind; | |||
5978 | ||||
5979 | /// Handle a builtin simple-assignment or a call to a trivial assignment | |||
5980 | /// operator whose left-hand side might involve a union member access. If it | |||
5981 | /// does, implicitly start the lifetime of any accessed union elements per | |||
5982 | /// C++20 [class.union]5. | |||
5983 | static bool HandleUnionActiveMemberChange(EvalInfo &Info, const Expr *LHSExpr, | |||
5984 | const LValue &LHS) { | |||
5985 | if (LHS.InvalidBase || LHS.Designator.Invalid) | |||
5986 | return false; | |||
5987 | ||||
5988 | llvm::SmallVector<std::pair<unsigned, const FieldDecl*>, 4> UnionPathLengths; | |||
5989 | // C++ [class.union]p5: | |||
5990 | // define the set S(E) of subexpressions of E as follows: | |||
5991 | unsigned PathLength = LHS.Designator.Entries.size(); | |||
5992 | for (const Expr *E = LHSExpr; E != nullptr;) { | |||
5993 | // -- If E is of the form A.B, S(E) contains the elements of S(A)... | |||
5994 | if (auto *ME = dyn_cast<MemberExpr>(E)) { | |||
5995 | auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()); | |||
5996 | // Note that we can't implicitly start the lifetime of a reference, | |||
5997 | // so we don't need to proceed any further if we reach one. | |||
5998 | if (!FD || FD->getType()->isReferenceType()) | |||
5999 | break; | |||
6000 | ||||
6001 | // ... and also contains A.B if B names a union member ... | |||
6002 | if (FD->getParent()->isUnion()) { | |||
6003 | // ... of a non-class, non-array type, or of a class type with a | |||
6004 | // trivial default constructor that is not deleted, or an array of | |||
6005 | // such types. | |||
6006 | auto *RD = | |||
6007 | FD->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); | |||
6008 | if (!RD || RD->hasTrivialDefaultConstructor()) | |||
6009 | UnionPathLengths.push_back({PathLength - 1, FD}); | |||
6010 | } | |||
6011 | ||||
6012 | E = ME->getBase(); | |||
6013 | --PathLength; | |||
6014 | assert(declaresSameEntity(FD,(static_cast <bool> (declaresSameEntity(FD, LHS.Designator .Entries[PathLength] .getAsBaseOrMember().getPointer())) ? void (0) : __assert_fail ("declaresSameEntity(FD, LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "clang/lib/AST/ExprConstant.cpp", 6016, __extension__ __PRETTY_FUNCTION__ )) | |||
6015 | LHS.Designator.Entries[PathLength](static_cast <bool> (declaresSameEntity(FD, LHS.Designator .Entries[PathLength] .getAsBaseOrMember().getPointer())) ? void (0) : __assert_fail ("declaresSameEntity(FD, LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "clang/lib/AST/ExprConstant.cpp", 6016, __extension__ __PRETTY_FUNCTION__ )) | |||
6016 | .getAsBaseOrMember().getPointer()))(static_cast <bool> (declaresSameEntity(FD, LHS.Designator .Entries[PathLength] .getAsBaseOrMember().getPointer())) ? void (0) : __assert_fail ("declaresSameEntity(FD, LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "clang/lib/AST/ExprConstant.cpp", 6016, __extension__ __PRETTY_FUNCTION__ )); | |||
6017 | ||||
6018 | // -- If E is of the form A[B] and is interpreted as a built-in array | |||
6019 | // subscripting operator, S(E) is [S(the array operand, if any)]. | |||
6020 | } else if (auto *ASE = dyn_cast<ArraySubscriptExpr>(E)) { | |||
6021 | // Step over an ArrayToPointerDecay implicit cast. | |||
6022 | auto *Base = ASE->getBase()->IgnoreImplicit(); | |||
6023 | if (!Base->getType()->isArrayType()) | |||
6024 | break; | |||
6025 | ||||
6026 | E = Base; | |||
6027 | --PathLength; | |||
6028 | ||||
6029 | } else if (auto *ICE = dyn_cast<ImplicitCastExpr>(E)) { | |||
6030 | // Step over a derived-to-base conversion. | |||
6031 | E = ICE->getSubExpr(); | |||
6032 | if (ICE->getCastKind() == CK_NoOp) | |||
6033 | continue; | |||
6034 | if (ICE->getCastKind() != CK_DerivedToBase && | |||
6035 | ICE->getCastKind() != CK_UncheckedDerivedToBase) | |||
6036 | break; | |||
6037 | // Walk path backwards as we walk up from the base to the derived class. | |||
6038 | for (const CXXBaseSpecifier *Elt : llvm::reverse(ICE->path())) { | |||
6039 | --PathLength; | |||
6040 | (void)Elt; | |||
6041 | assert(declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(),(static_cast <bool> (declaresSameEntity(Elt->getType ()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength ] .getAsBaseOrMember().getPointer())) ? void (0) : __assert_fail ("declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "clang/lib/AST/ExprConstant.cpp", 6043, __extension__ __PRETTY_FUNCTION__ )) | |||
6042 | LHS.Designator.Entries[PathLength](static_cast <bool> (declaresSameEntity(Elt->getType ()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength ] .getAsBaseOrMember().getPointer())) ? void (0) : __assert_fail ("declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "clang/lib/AST/ExprConstant.cpp", 6043, __extension__ __PRETTY_FUNCTION__ )) | |||
6043 | .getAsBaseOrMember().getPointer()))(static_cast <bool> (declaresSameEntity(Elt->getType ()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength ] .getAsBaseOrMember().getPointer())) ? void (0) : __assert_fail ("declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "clang/lib/AST/ExprConstant.cpp", 6043, __extension__ __PRETTY_FUNCTION__ )); | |||
6044 | } | |||
6045 | ||||
6046 | // -- Otherwise, S(E) is empty. | |||
6047 | } else { | |||
6048 | break; | |||
6049 | } | |||
6050 | } | |||
6051 | ||||
6052 | // Common case: no unions' lifetimes are started. | |||
6053 | if (UnionPathLengths.empty()) | |||
6054 | return true; | |||
6055 | ||||
6056 | // if modification of X [would access an inactive union member], an object | |||
6057 | // of the type of X is implicitly created | |||
6058 | CompleteObject Obj = | |||
6059 | findCompleteObject(Info, LHSExpr, AK_Assign, LHS, LHSExpr->getType()); | |||
| ||||
6060 | if (!Obj) | |||
6061 | return false; | |||
6062 | for (std::pair<unsigned, const FieldDecl *> LengthAndField : | |||
6063 | llvm::reverse(UnionPathLengths)) { | |||
6064 | // Form a designator for the union object. | |||
6065 | SubobjectDesignator D = LHS.Designator; | |||
6066 | D.truncate(Info.Ctx, LHS.Base, LengthAndField.first); | |||
6067 | ||||
6068 | bool DuringInit = Info.isEvaluatingCtorDtor(LHS.Base, D.Entries) == | |||
6069 | ConstructionPhase::AfterBases; | |||
6070 | StartLifetimeOfUnionMemberHandler StartLifetime{ | |||
6071 | Info, LHSExpr, LengthAndField.second, DuringInit}; | |||
6072 | if (!findSubobject(Info, LHSExpr, Obj, D, StartLifetime)) | |||
6073 | return false; | |||
6074 | } | |||
6075 | ||||
6076 | return true; | |||
6077 | } | |||
6078 | ||||
6079 | static bool EvaluateCallArg(const ParmVarDecl *PVD, const Expr *Arg, | |||
6080 | CallRef Call, EvalInfo &Info, | |||
6081 | bool NonNull = false) { | |||
6082 | LValue LV; | |||
6083 | // Create the parameter slot and register its destruction. For a vararg | |||
6084 | // argument, create a temporary. | |||
6085 | // FIXME: For calling conventions that destroy parameters in the callee, | |||
6086 | // should we consider performing destruction when the function returns | |||
6087 | // instead? | |||
6088 | APValue &V = PVD ? Info.CurrentCall->createParam(Call, PVD, LV) | |||
6089 | : Info.CurrentCall->createTemporary(Arg, Arg->getType(), | |||
6090 | ScopeKind::Call, LV); | |||
6091 | if (!EvaluateInPlace(V, Info, LV, Arg)) | |||
6092 | return false; | |||
6093 | ||||
6094 | // Passing a null pointer to an __attribute__((nonnull)) parameter results in | |||
6095 | // undefined behavior, so is non-constant. | |||
6096 | if (NonNull && V.isLValue() && V.isNullPointer()) { | |||
6097 | Info.CCEDiag(Arg, diag::note_non_null_attribute_failed); | |||
6098 | return false; | |||
6099 | } | |||
6100 | ||||
6101 | return true; | |||
6102 | } | |||
6103 | ||||
6104 | /// Evaluate the arguments to a function call. | |||
6105 | static bool EvaluateArgs(ArrayRef<const Expr *> Args, CallRef Call, | |||
6106 | EvalInfo &Info, const FunctionDecl *Callee, | |||
6107 | bool RightToLeft = false) { | |||
6108 | bool Success = true; | |||
6109 | llvm::SmallBitVector ForbiddenNullArgs; | |||
6110 | if (Callee->hasAttr<NonNullAttr>()) { | |||
6111 | ForbiddenNullArgs.resize(Args.size()); | |||
6112 | for (const auto *Attr : Callee->specific_attrs<NonNullAttr>()) { | |||
6113 | if (!Attr->args_size()) { | |||
6114 | ForbiddenNullArgs.set(); | |||
6115 | break; | |||
6116 | } else | |||
6117 | for (auto Idx : Attr->args()) { | |||
6118 | unsigned ASTIdx = Idx.getASTIndex(); | |||
6119 | if (ASTIdx >= Args.size()) | |||
6120 | continue; | |||
6121 | ForbiddenNullArgs[ASTIdx] = true; | |||
6122 | } | |||
6123 | } | |||
6124 | } | |||
6125 | for (unsigned I = 0; I < Args.size(); I++) { | |||
6126 | unsigned Idx = RightToLeft ? Args.size() - I - 1 : I; | |||
6127 | const ParmVarDecl *PVD = | |||
6128 | Idx < Callee->getNumParams() ? Callee->getParamDecl(Idx) : nullptr; | |||
6129 | bool NonNull = !ForbiddenNullArgs.empty() && ForbiddenNullArgs[Idx]; | |||
6130 | if (!EvaluateCallArg(PVD, Args[Idx], Call, Info, NonNull)) { | |||
6131 | // If we're checking for a potential constant expression, evaluate all | |||
6132 | // initializers even if some of them fail. | |||
6133 | if (!Info.noteFailure()) | |||
6134 | return false; | |||
6135 | Success = false; | |||
6136 | } | |||
6137 | } | |||
6138 | return Success; | |||
6139 | } | |||
6140 | ||||
6141 | /// Perform a trivial copy from Param, which is the parameter of a copy or move | |||
6142 | /// constructor or assignment operator. | |||
6143 | static bool handleTrivialCopy(EvalInfo &Info, const ParmVarDecl *Param, | |||
6144 | const Expr *E, APValue &Result, | |||
6145 | bool CopyObjectRepresentation) { | |||
6146 | // Find the reference argument. | |||
6147 | CallStackFrame *Frame = Info.CurrentCall; | |||
6148 | APValue *RefValue = Info.getParamSlot(Frame->Arguments, Param); | |||
6149 | if (!RefValue) { | |||
6150 | Info.FFDiag(E); | |||
6151 | return false; | |||
6152 | } | |||
6153 | ||||
6154 | // Copy out the contents of the RHS object. | |||
6155 | LValue RefLValue; | |||
6156 | RefLValue.setFrom(Info.Ctx, *RefValue); | |||
6157 | return handleLValueToRValueConversion( | |||
6158 | Info, E, Param->getType().getNonReferenceType(), RefLValue, Result, | |||
6159 | CopyObjectRepresentation); | |||
6160 | } | |||
6161 | ||||
6162 | /// Evaluate a function call. | |||
6163 | static bool HandleFunctionCall(SourceLocation CallLoc, | |||
6164 | const FunctionDecl *Callee, const LValue *This, | |||
6165 | ArrayRef<const Expr *> Args, CallRef Call, | |||
6166 | const Stmt *Body, EvalInfo &Info, | |||
6167 | APValue &Result, const LValue *ResultSlot) { | |||
6168 | if (!Info.CheckCallLimit(CallLoc)) | |||
6169 | return false; | |||
6170 | ||||
6171 | CallStackFrame Frame(Info, CallLoc, Callee, This, Call); | |||
6172 | ||||
6173 | // For a trivial copy or move assignment, perform an APValue copy. This is | |||
6174 | // essential for unions, where the operations performed by the assignment | |||
6175 | // operator cannot be represented as statements. | |||
6176 | // | |||
6177 | // Skip this for non-union classes with no fields; in that case, the defaulted | |||
6178 | // copy/move does not actually read the object. | |||
6179 | const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Callee); | |||
6180 | if (MD && MD->isDefaulted() && | |||
6181 | (MD->getParent()->isUnion() || | |||
6182 | (MD->isTrivial() && | |||
6183 | isReadByLvalueToRvalueConversion(MD->getParent())))) { | |||
6184 | assert(This &&(static_cast <bool> (This && (MD->isCopyAssignmentOperator () || MD->isMoveAssignmentOperator())) ? void (0) : __assert_fail ("This && (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())" , "clang/lib/AST/ExprConstant.cpp", 6185, __extension__ __PRETTY_FUNCTION__ )) | |||
6185 | (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator()))(static_cast <bool> (This && (MD->isCopyAssignmentOperator () || MD->isMoveAssignmentOperator())) ? void (0) : __assert_fail ("This && (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())" , "clang/lib/AST/ExprConstant.cpp", 6185, __extension__ __PRETTY_FUNCTION__ )); | |||
6186 | APValue RHSValue; | |||
6187 | if (!handleTrivialCopy(Info, MD->getParamDecl(0), Args[0], RHSValue, | |||
6188 | MD->getParent()->isUnion())) | |||
6189 | return false; | |||
6190 | if (!handleAssignment(Info, Args[0], *This, MD->getThisType(), | |||
6191 | RHSValue)) | |||
6192 | return false; | |||
6193 | This->moveInto(Result); | |||
6194 | return true; | |||
6195 | } else if (MD && isLambdaCallOperator(MD)) { | |||
6196 | // We're in a lambda; determine the lambda capture field maps unless we're | |||
6197 | // just constexpr checking a lambda's call operator. constexpr checking is | |||
6198 | // done before the captures have been added to the closure object (unless | |||
6199 | // we're inferring constexpr-ness), so we don't have access to them in this | |||
6200 | // case. But since we don't need the captures to constexpr check, we can | |||
6201 | // just ignore them. | |||
6202 | if (!Info.checkingPotentialConstantExpression()) | |||
6203 | MD->getParent()->getCaptureFields(Frame.LambdaCaptureFields, | |||
6204 | Frame.LambdaThisCaptureField); | |||
6205 | } | |||
6206 | ||||
6207 | StmtResult Ret = {Result, ResultSlot}; | |||
6208 | EvalStmtResult ESR = EvaluateStmt(Ret, Info, Body); | |||
6209 | if (ESR == ESR_Succeeded) { | |||
6210 | if (Callee->getReturnType()->isVoidType()) | |||
6211 | return true; | |||
6212 | Info.FFDiag(Callee->getEndLoc(), diag::note_constexpr_no_return); | |||
6213 | } | |||
6214 | return ESR == ESR_Returned; | |||
6215 | } | |||
6216 | ||||
6217 | /// Evaluate a constructor call. | |||
6218 | static bool HandleConstructorCall(const Expr *E, const LValue &This, | |||
6219 | CallRef Call, | |||
6220 | const CXXConstructorDecl *Definition, | |||
6221 | EvalInfo &Info, APValue &Result) { | |||
6222 | SourceLocation CallLoc = E->getExprLoc(); | |||
6223 | if (!Info.CheckCallLimit(CallLoc)) | |||
6224 | return false; | |||
6225 | ||||
6226 | const CXXRecordDecl *RD = Definition->getParent(); | |||
6227 | if (RD->getNumVBases()) { | |||
6228 | Info.FFDiag(CallLoc, diag::note_constexpr_virtual_base) << RD; | |||
6229 | return false; | |||
6230 | } | |||
6231 | ||||
6232 | EvalInfo::EvaluatingConstructorRAII EvalObj( | |||
6233 | Info, | |||
6234 | ObjectUnderConstruction{This.getLValueBase(), This.Designator.Entries}, | |||
6235 | RD->getNumBases()); | |||
6236 | CallStackFrame Frame(Info, CallLoc, Definition, &This, Call); | |||
6237 | ||||
6238 | // FIXME: Creating an APValue just to hold a nonexistent return value is | |||
6239 | // wasteful. | |||
6240 | APValue RetVal; | |||
6241 | StmtResult Ret = {RetVal, nullptr}; | |||
6242 | ||||
6243 | // If it's a delegating constructor, delegate. | |||
6244 | if (Definition->isDelegatingConstructor()) { | |||
6245 | CXXConstructorDecl::init_const_iterator I = Definition->init_begin(); | |||
6246 | if ((*I)->getInit()->isValueDependent()) { | |||
6247 | if (!EvaluateDependentExpr((*I)->getInit(), Info)) | |||
6248 | return false; | |||
6249 | } else { | |||
6250 | FullExpressionRAII InitScope(Info); | |||
6251 | if (!EvaluateInPlace(Result, Info, This, (*I)->getInit()) || | |||
6252 | !InitScope.destroy()) | |||
6253 | return false; | |||
6254 | } | |||
6255 | return EvaluateStmt(Ret, Info, Definition->getBody()) != ESR_Failed; | |||
6256 | } | |||
6257 | ||||
6258 | // For a trivial copy or move constructor, perform an APValue copy. This is | |||
6259 | // essential for unions (or classes with anonymous union members), where the | |||
6260 | // operations performed by the constructor cannot be represented by | |||
6261 | // ctor-initializers. | |||
6262 | // | |||
6263 | // Skip this for empty non-union classes; we should not perform an | |||
6264 | // lvalue-to-rvalue conversion on them because their copy constructor does not | |||
6265 | // actually read them. | |||
6266 | if (Definition->isDefaulted() && Definition->isCopyOrMoveConstructor() && | |||
6267 | (Definition->getParent()->isUnion() || | |||
6268 | (Definition->isTrivial() && | |||
6269 | isReadByLvalueToRvalueConversion(Definition->getParent())))) { | |||
6270 | return handleTrivialCopy(Info, Definition->getParamDecl(0), E, Result, | |||
6271 | Definition->getParent()->isUnion()); | |||
6272 | } | |||
6273 | ||||
6274 | // Reserve space for the struct members. | |||
6275 | if (!Result.hasValue()) { | |||
6276 | if (!RD->isUnion()) | |||
6277 | Result = APValue(APValue::UninitStruct(), RD->getNumBases(), | |||
6278 | std::distance(RD->field_begin(), RD->field_end())); | |||
6279 | else | |||
6280 | // A union starts with no active member. | |||
6281 | Result = APValue((const FieldDecl*)nullptr); | |||
6282 | } | |||
6283 | ||||
6284 | if (RD->isInvalidDecl()) return false; | |||
6285 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
6286 | ||||
6287 | // A scope for temporaries lifetime-extended by reference members. | |||
6288 | BlockScopeRAII LifetimeExtendedScope(Info); | |||
6289 | ||||
6290 | bool Success = true; | |||
6291 | unsigned BasesSeen = 0; | |||
6292 | #ifndef NDEBUG | |||
6293 | CXXRecordDecl::base_class_const_iterator BaseIt = RD->bases_begin(); | |||
6294 | #endif | |||
6295 | CXXRecordDecl::field_iterator FieldIt = RD->field_begin(); | |||
6296 | auto SkipToField = [&](FieldDecl *FD, bool Indirect) { | |||
6297 | // We might be initializing the same field again if this is an indirect | |||
6298 | // field initialization. | |||
6299 | if (FieldIt == RD->field_end() || | |||
6300 | FieldIt->getFieldIndex() > FD->getFieldIndex()) { | |||
6301 | assert(Indirect && "fields out of order?")(static_cast <bool> (Indirect && "fields out of order?" ) ? void (0) : __assert_fail ("Indirect && \"fields out of order?\"" , "clang/lib/AST/ExprConstant.cpp", 6301, __extension__ __PRETTY_FUNCTION__ )); | |||
6302 | return; | |||
6303 | } | |||
6304 | ||||
6305 | // Default-initialize any fields with no explicit initializer. | |||
6306 | for (; !declaresSameEntity(*FieldIt, FD); ++FieldIt) { | |||
6307 | assert(FieldIt != RD->field_end() && "missing field?")(static_cast <bool> (FieldIt != RD->field_end() && "missing field?") ? void (0) : __assert_fail ("FieldIt != RD->field_end() && \"missing field?\"" , "clang/lib/AST/ExprConstant.cpp", 6307, __extension__ __PRETTY_FUNCTION__ )); | |||
6308 | if (!FieldIt->isUnnamedBitfield()) | |||
6309 | Success &= getDefaultInitValue( | |||
6310 | FieldIt->getType(), | |||
6311 | Result.getStructField(FieldIt->getFieldIndex())); | |||
6312 | } | |||
6313 | ++FieldIt; | |||
6314 | }; | |||
6315 | for (const auto *I : Definition->inits()) { | |||
6316 | LValue Subobject = This; | |||
6317 | LValue SubobjectParent = This; | |||
6318 | APValue *Value = &Result; | |||
6319 | ||||
6320 | // Determine the subobject to initialize. | |||
6321 | FieldDecl *FD = nullptr; | |||
6322 | if (I->isBaseInitializer()) { | |||
6323 | QualType BaseType(I->getBaseClass(), 0); | |||
6324 | #ifndef NDEBUG | |||
6325 | // Non-virtual base classes are initialized in the order in the class | |||
6326 | // definition. We have already checked for virtual base classes. | |||
6327 | assert(!BaseIt->isVirtual() && "virtual base for literal type")(static_cast <bool> (!BaseIt->isVirtual() && "virtual base for literal type") ? void (0) : __assert_fail ( "!BaseIt->isVirtual() && \"virtual base for literal type\"" , "clang/lib/AST/ExprConstant.cpp", 6327, __extension__ __PRETTY_FUNCTION__ )); | |||
6328 | assert(Info.Ctx.hasSameType(BaseIt->getType(), BaseType) &&(static_cast <bool> (Info.Ctx.hasSameType(BaseIt->getType (), BaseType) && "base class initializers not in expected order" ) ? void (0) : __assert_fail ("Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && \"base class initializers not in expected order\"" , "clang/lib/AST/ExprConstant.cpp", 6329, __extension__ __PRETTY_FUNCTION__ )) | |||
6329 | "base class initializers not in expected order")(static_cast <bool> (Info.Ctx.hasSameType(BaseIt->getType (), BaseType) && "base class initializers not in expected order" ) ? void (0) : __assert_fail ("Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && \"base class initializers not in expected order\"" , "clang/lib/AST/ExprConstant.cpp", 6329, __extension__ __PRETTY_FUNCTION__ )); | |||
6330 | ++BaseIt; | |||
6331 | #endif | |||
6332 | if (!HandleLValueDirectBase(Info, I->getInit(), Subobject, RD, | |||
6333 | BaseType->getAsCXXRecordDecl(), &Layout)) | |||
6334 | return false; | |||
6335 | Value = &Result.getStructBase(BasesSeen++); | |||
6336 | } else if ((FD = I->getMember())) { | |||
6337 | if (!HandleLValueMember(Info, I->getInit(), Subobject, FD, &Layout)) | |||
6338 | return false; | |||
6339 | if (RD->isUnion()) { | |||
6340 | Result = APValue(FD); | |||
6341 | Value = &Result.getUnionValue(); | |||
6342 | } else { | |||
6343 | SkipToField(FD, false); | |||
6344 | Value = &Result.getStructField(FD->getFieldIndex()); | |||
6345 | } | |||
6346 | } else if (IndirectFieldDecl *IFD = I->getIndirectMember()) { | |||
6347 | // Walk the indirect field decl's chain to find the object to initialize, | |||
6348 | // and make sure we've initialized every step along it. | |||
6349 | auto IndirectFieldChain = IFD->chain(); | |||
6350 | for (auto *C : IndirectFieldChain) { | |||
6351 | FD = cast<FieldDecl>(C); | |||
6352 | CXXRecordDecl *CD = cast<CXXRecordDecl>(FD->getParent()); | |||
6353 | // Switch the union field if it differs. This happens if we had | |||
6354 | // preceding zero-initialization, and we're now initializing a union | |||
6355 | // subobject other than the first. | |||
6356 | // FIXME: In this case, the values of the other subobjects are | |||
6357 | // specified, since zero-initialization sets all padding bits to zero. | |||
6358 | if (!Value->hasValue() || | |||
6359 | (Value->isUnion() && Value->getUnionField() != FD)) { | |||
6360 | if (CD->isUnion()) | |||
6361 | *Value = APValue(FD); | |||
6362 | else | |||
6363 | // FIXME: This immediately starts the lifetime of all members of | |||
6364 | // an anonymous struct. It would be preferable to strictly start | |||
6365 | // member lifetime in initialization order. | |||
6366 | Success &= getDefaultInitValue(Info.Ctx.getRecordType(CD), *Value); | |||
6367 | } | |||
6368 | // Store Subobject as its parent before updating it for the last element | |||
6369 | // in the chain. | |||
6370 | if (C == IndirectFieldChain.back()) | |||
6371 | SubobjectParent = Subobject; | |||
6372 | if (!HandleLValueMember(Info, I->getInit(), Subobject, FD)) | |||
6373 | return false; | |||
6374 | if (CD->isUnion()) | |||
6375 | Value = &Value->getUnionValue(); | |||
6376 | else { | |||
6377 | if (C == IndirectFieldChain.front() && !RD->isUnion()) | |||
6378 | SkipToField(FD, true); | |||
6379 | Value = &Value->getStructField(FD->getFieldIndex()); | |||
6380 | } | |||
6381 | } | |||
6382 | } else { | |||
6383 | llvm_unreachable("unknown base initializer kind")::llvm::llvm_unreachable_internal("unknown base initializer kind" , "clang/lib/AST/ExprConstant.cpp", 6383); | |||
6384 | } | |||
6385 | ||||
6386 | // Need to override This for implicit field initializers as in this case | |||
6387 | // This refers to innermost anonymous struct/union containing initializer, | |||
6388 | // not to currently constructed class. | |||
6389 | const Expr *Init = I->getInit(); | |||
6390 | if (Init->isValueDependent()) { | |||
6391 | if (!EvaluateDependentExpr(Init, Info)) | |||
6392 | return false; | |||
6393 | } else { | |||
6394 | ThisOverrideRAII ThisOverride(*Info.CurrentCall, &SubobjectParent, | |||
6395 | isa<CXXDefaultInitExpr>(Init)); | |||
6396 | FullExpressionRAII InitScope(Info); | |||
6397 | if (!EvaluateInPlace(*Value, Info, Subobject, Init) || | |||
6398 | (FD && FD->isBitField() && | |||
6399 | !truncateBitfieldValue(Info, Init, *Value, FD))) { | |||
6400 | // If we're checking for a potential constant expression, evaluate all | |||
6401 | // initializers even if some of them fail. | |||
6402 | if (!Info.noteFailure()) | |||
6403 | return false; | |||
6404 | Success = false; | |||
6405 | } | |||
6406 | } | |||
6407 | ||||
6408 | // This is the point at which the dynamic type of the object becomes this | |||
6409 | // class type. | |||
6410 | if (I->isBaseInitializer() && BasesSeen == RD->getNumBases()) | |||
6411 | EvalObj.finishedConstructingBases(); | |||
6412 | } | |||
6413 | ||||
6414 | // Default-initialize any remaining fields. | |||
6415 | if (!RD->isUnion()) { | |||
6416 | for (; FieldIt != RD->field_end(); ++FieldIt) { | |||
6417 | if (!FieldIt->isUnnamedBitfield()) | |||
6418 | Success &= getDefaultInitValue( | |||
6419 | FieldIt->getType(), | |||
6420 | Result.getStructField(FieldIt->getFieldIndex())); | |||
6421 | } | |||
6422 | } | |||
6423 | ||||
6424 | EvalObj.finishedConstructingFields(); | |||
6425 | ||||
6426 | return Success && | |||
6427 | EvaluateStmt(Ret, Info, Definition->getBody()) != ESR_Failed && | |||
6428 | LifetimeExtendedScope.destroy(); | |||
6429 | } | |||
6430 | ||||
6431 | static bool HandleConstructorCall(const Expr *E, const LValue &This, | |||
6432 | ArrayRef<const Expr*> Args, | |||
6433 | const CXXConstructorDecl *Definition, | |||
6434 | EvalInfo &Info, APValue &Result) { | |||
6435 | CallScopeRAII CallScope(Info); | |||
6436 | CallRef Call = Info.CurrentCall->createCall(Definition); | |||
6437 | if (!EvaluateArgs(Args, Call, Info, Definition)) | |||
6438 | return false; | |||
6439 | ||||
6440 | return HandleConstructorCall(E, This, Call, Definition, Info, Result) && | |||
6441 | CallScope.destroy(); | |||
6442 | } | |||
6443 | ||||
6444 | static bool HandleDestructionImpl(EvalInfo &Info, SourceLocation CallLoc, | |||
6445 | const LValue &This, APValue &Value, | |||
6446 | QualType T) { | |||
6447 | // Objects can only be destroyed while they're within their lifetimes. | |||
6448 | // FIXME: We have no representation for whether an object of type nullptr_t | |||
6449 | // is in its lifetime; it usually doesn't matter. Perhaps we should model it | |||
6450 | // as indeterminate instead? | |||
6451 | if (Value.isAbsent() && !T->isNullPtrType()) { | |||
6452 | APValue Printable; | |||
6453 | This.moveInto(Printable); | |||
6454 | Info.FFDiag(CallLoc, diag::note_constexpr_destroy_out_of_lifetime) | |||
6455 | << Printable.getAsString(Info.Ctx, Info.Ctx.getLValueReferenceType(T)); | |||
6456 | return false; | |||
6457 | } | |||
6458 | ||||
6459 | // Invent an expression for location purposes. | |||
6460 | // FIXME: We shouldn't need to do this. | |||
6461 | OpaqueValueExpr LocE(CallLoc, Info.Ctx.IntTy, VK_PRValue); | |||
6462 | ||||
6463 | // For arrays, destroy elements right-to-left. | |||
6464 | if (const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(T)) { | |||
6465 | uint64_t Size = CAT->getSize().getZExtValue(); | |||
6466 | QualType ElemT = CAT->getElementType(); | |||
6467 | ||||
6468 | LValue ElemLV = This; | |||
6469 | ElemLV.addArray(Info, &LocE, CAT); | |||
6470 | if (!HandleLValueArrayAdjustment(Info, &LocE, ElemLV, ElemT, Size)) | |||
6471 | return false; | |||
6472 | ||||
6473 | // Ensure that we have actual array elements available to destroy; the | |||
6474 | // destructors might mutate the value, so we can't run them on the array | |||
6475 | // filler. | |||
6476 | if (Size && Size > Value.getArrayInitializedElts()) | |||
6477 | expandArray(Value, Value.getArraySize() - 1); | |||
6478 | ||||
6479 | for (; Size != 0; --Size) { | |||
6480 | APValue &Elem = Value.getArrayInitializedElt(Size - 1); | |||
6481 | if (!HandleLValueArrayAdjustment(Info, &LocE, ElemLV, ElemT, -1) || | |||
6482 | !HandleDestructionImpl(Info, CallLoc, ElemLV, Elem, ElemT)) | |||
6483 | return false; | |||
6484 | } | |||
6485 | ||||
6486 | // End the lifetime of this array now. | |||
6487 | Value = APValue(); | |||
6488 | return true; | |||
6489 | } | |||
6490 | ||||
6491 | const CXXRecordDecl *RD = T->getAsCXXRecordDecl(); | |||
6492 | if (!RD) { | |||
6493 | if (T.isDestructedType()) { | |||
6494 | Info.FFDiag(CallLoc, diag::note_constexpr_unsupported_destruction) << T; | |||
6495 | return false; | |||
6496 | } | |||
6497 | ||||
6498 | Value = APValue(); | |||
6499 | return true; | |||
6500 | } | |||
6501 | ||||
6502 | if (RD->getNumVBases()) { | |||
6503 | Info.FFDiag(CallLoc, diag::note_constexpr_virtual_base) << RD; | |||
6504 | return false; | |||
6505 | } | |||
6506 | ||||
6507 | const CXXDestructorDecl *DD = RD->getDestructor(); | |||
6508 | if (!DD && !RD->hasTrivialDestructor()) { | |||
6509 | Info.FFDiag(CallLoc); | |||
6510 | return false; | |||
6511 | } | |||
6512 | ||||
6513 | if (!DD || DD->isTrivial() || | |||
6514 | (RD->isAnonymousStructOrUnion() && RD->isUnion())) { | |||
6515 | // A trivial destructor just ends the lifetime of the object. Check for | |||
6516 | // this case before checking for a body, because we might not bother | |||
6517 | // building a body for a trivial destructor. Note that it doesn't matter | |||
6518 | // whether the destructor is constexpr in this case; all trivial | |||
6519 | // destructors are constexpr. | |||
6520 | // | |||
6521 | // If an anonymous union would be destroyed, some enclosing destructor must | |||
6522 | // have been explicitly defined, and the anonymous union destruction should | |||
6523 | // have no effect. | |||
6524 | Value = APValue(); | |||
6525 | return true; | |||
6526 | } | |||
6527 | ||||
6528 | if (!Info.CheckCallLimit(CallLoc)) | |||
6529 | return false; | |||
6530 | ||||
6531 | const FunctionDecl *Definition = nullptr; | |||
6532 | const Stmt *Body = DD->getBody(Definition); | |||
6533 | ||||
6534 | if (!CheckConstexprFunction(Info, CallLoc, DD, Definition, Body)) | |||
6535 | return false; | |||
6536 | ||||
6537 | CallStackFrame Frame(Info, CallLoc, Definition, &This, CallRef()); | |||
6538 | ||||
6539 | // We're now in the period of destruction of this object. | |||
6540 | unsigned BasesLeft = RD->getNumBases(); | |||
6541 | EvalInfo::EvaluatingDestructorRAII EvalObj( | |||
6542 | Info, | |||
6543 | ObjectUnderConstruction{This.getLValueBase(), This.Designator.Entries}); | |||
6544 | if (!EvalObj.DidInsert) { | |||
6545 | // C++2a [class.dtor]p19: | |||
6546 | // the behavior is undefined if the destructor is invoked for an object | |||
6547 | // whose lifetime has ended | |||
6548 | // (Note that formally the lifetime ends when the period of destruction | |||
6549 | // begins, even though certain uses of the object remain valid until the | |||
6550 | // period of destruction ends.) | |||
6551 | Info.FFDiag(CallLoc, diag::note_constexpr_double_destroy); | |||
6552 | return false; | |||
6553 | } | |||
6554 | ||||
6555 | // FIXME: Creating an APValue just to hold a nonexistent return value is | |||
6556 | // wasteful. | |||
6557 | APValue RetVal; | |||
6558 | StmtResult Ret = {RetVal, nullptr}; | |||
6559 | if (EvaluateStmt(Ret, Info, Definition->getBody()) == ESR_Failed) | |||
6560 | return false; | |||
6561 | ||||
6562 | // A union destructor does not implicitly destroy its members. | |||
6563 | if (RD->isUnion()) | |||
6564 | return true; | |||
6565 | ||||
6566 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
6567 | ||||
6568 | // We don't have a good way to iterate fields in reverse, so collect all the | |||
6569 | // fields first and then walk them backwards. | |||
6570 | SmallVector<FieldDecl*, 16> Fields(RD->fields()); | |||
6571 | for (const FieldDecl *FD : llvm::reverse(Fields)) { | |||
6572 | if (FD->isUnnamedBitfield()) | |||
6573 | continue; | |||
6574 | ||||
6575 | LValue Subobject = This; | |||
6576 | if (!HandleLValueMember(Info, &LocE, Subobject, FD, &Layout)) | |||
6577 | return false; | |||
6578 | ||||
6579 | APValue *SubobjectValue = &Value.getStructField(FD->getFieldIndex()); | |||
6580 | if (!HandleDestructionImpl(Info, CallLoc, Subobject, *SubobjectValue, | |||
6581 | FD->getType())) | |||
6582 | return false; | |||
6583 | } | |||
6584 | ||||
6585 | if (BasesLeft != 0) | |||
6586 | EvalObj.startedDestroyingBases(); | |||
6587 | ||||
6588 | // Destroy base classes in reverse order. | |||
6589 | for (const CXXBaseSpecifier &Base : llvm::reverse(RD->bases())) { | |||
6590 | --BasesLeft; | |||
6591 | ||||
6592 | QualType BaseType = Base.getType(); | |||
6593 | LValue Subobject = This; | |||
6594 | if (!HandleLValueDirectBase(Info, &LocE, Subobject, RD, | |||
6595 | BaseType->getAsCXXRecordDecl(), &Layout)) | |||
6596 | return false; | |||
6597 | ||||
6598 | APValue *SubobjectValue = &Value.getStructBase(BasesLeft); | |||
6599 | if (!HandleDestructionImpl(Info, CallLoc, Subobject, *SubobjectValue, | |||
6600 | BaseType)) | |||
6601 | return false; | |||
6602 | } | |||
6603 | assert(BasesLeft == 0 && "NumBases was wrong?")(static_cast <bool> (BasesLeft == 0 && "NumBases was wrong?" ) ? void (0) : __assert_fail ("BasesLeft == 0 && \"NumBases was wrong?\"" , "clang/lib/AST/ExprConstant.cpp", 6603, __extension__ __PRETTY_FUNCTION__ )); | |||
6604 | ||||
6605 | // The period of destruction ends now. The object is gone. | |||
6606 | Value = APValue(); | |||
6607 | return true; | |||
6608 | } | |||
6609 | ||||
6610 | namespace { | |||
6611 | struct DestroyObjectHandler { | |||
6612 | EvalInfo &Info; | |||
6613 | const Expr *E; | |||
6614 | const LValue &This; | |||
6615 | const AccessKinds AccessKind; | |||
6616 | ||||
6617 | typedef bool result_type; | |||
6618 | bool failed() { return false; } | |||
6619 | bool found(APValue &Subobj, QualType SubobjType) { | |||
6620 | return HandleDestructionImpl(Info, E->getExprLoc(), This, Subobj, | |||
6621 | SubobjType); | |||
6622 | } | |||
6623 | bool found(APSInt &Value, QualType SubobjType) { | |||
6624 | Info.FFDiag(E, diag::note_constexpr_destroy_complex_elem); | |||
6625 | return false; | |||
6626 | } | |||
6627 | bool found(APFloat &Value, QualType SubobjType) { | |||
6628 | Info.FFDiag(E, diag::note_constexpr_destroy_complex_elem); | |||
6629 | return false; | |||
6630 | } | |||
6631 | }; | |||
6632 | } | |||
6633 | ||||
6634 | /// Perform a destructor or pseudo-destructor call on the given object, which | |||
6635 | /// might in general not be a complete object. | |||
6636 | static bool HandleDestruction(EvalInfo &Info, const Expr *E, | |||
6637 | const LValue &This, QualType ThisType) { | |||
6638 | CompleteObject Obj = findCompleteObject(Info, E, AK_Destroy, This, ThisType); | |||
6639 | DestroyObjectHandler Handler = {Info, E, This, AK_Destroy}; | |||
6640 | return Obj && findSubobject(Info, E, Obj, This.Designator, Handler); | |||
6641 | } | |||
6642 | ||||
6643 | /// Destroy and end the lifetime of the given complete object. | |||
6644 | static bool HandleDestruction(EvalInfo &Info, SourceLocation Loc, | |||
6645 | APValue::LValueBase LVBase, APValue &Value, | |||
6646 | QualType T) { | |||
6647 | // If we've had an unmodeled side-effect, we can't rely on mutable state | |||
6648 | // (such as the object we're about to destroy) being correct. | |||
6649 | if (Info.EvalStatus.HasSideEffects) | |||
6650 | return false; | |||
6651 | ||||
6652 | LValue LV; | |||
6653 | LV.set({LVBase}); | |||
6654 | return HandleDestructionImpl(Info, Loc, LV, Value, T); | |||
6655 | } | |||
6656 | ||||
6657 | /// Perform a call to 'perator new' or to `__builtin_operator_new'. | |||
6658 | static bool HandleOperatorNewCall(EvalInfo &Info, const CallExpr *E, | |||
6659 | LValue &Result) { | |||
6660 | if (Info.checkingPotentialConstantExpression() || | |||
6661 | Info.SpeculativeEvaluationDepth) | |||
6662 | return false; | |||
6663 | ||||
6664 | // This is permitted only within a call to std::allocator<T>::allocate. | |||
6665 | auto Caller = Info.getStdAllocatorCaller("allocate"); | |||
6666 | if (!Caller) { | |||
6667 | Info.FFDiag(E->getExprLoc(), Info.getLangOpts().CPlusPlus20 | |||
6668 | ? diag::note_constexpr_new_untyped | |||
6669 | : diag::note_constexpr_new); | |||
6670 | return false; | |||
6671 | } | |||
6672 | ||||
6673 | QualType ElemType = Caller.ElemType; | |||
6674 | if (ElemType->isIncompleteType() || ElemType->isFunctionType()) { | |||
6675 | Info.FFDiag(E->getExprLoc(), | |||
6676 | diag::note_constexpr_new_not_complete_object_type) | |||
6677 | << (ElemType->isIncompleteType() ? 0 : 1) << ElemType; | |||
6678 | return false; | |||
6679 | } | |||
6680 | ||||
6681 | APSInt ByteSize; | |||
6682 | if (!EvaluateInteger(E->getArg(0), ByteSize, Info)) | |||
6683 | return false; | |||
6684 | bool IsNothrow = false; | |||
6685 | for (unsigned I = 1, N = E->getNumArgs(); I != N; ++I) { | |||
6686 | EvaluateIgnoredValue(Info, E->getArg(I)); | |||
6687 | IsNothrow |= E->getType()->isNothrowT(); | |||
6688 | } | |||
6689 | ||||
6690 | CharUnits ElemSize; | |||
6691 | if (!HandleSizeof(Info, E->getExprLoc(), ElemType, ElemSize)) | |||
6692 | return false; | |||
6693 | APInt Size, Remainder; | |||
6694 | APInt ElemSizeAP(ByteSize.getBitWidth(), ElemSize.getQuantity()); | |||
6695 | APInt::udivrem(ByteSize, ElemSizeAP, Size, Remainder); | |||
6696 | if (Remainder != 0) { | |||
6697 | // This likely indicates a bug in the implementation of 'std::allocator'. | |||
6698 | Info.FFDiag(E->getExprLoc(), diag::note_constexpr_operator_new_bad_size) | |||
6699 | << ByteSize << APSInt(ElemSizeAP, true) << ElemType; | |||
6700 | return false; | |||
6701 | } | |||
6702 | ||||
6703 | if (ByteSize.getActiveBits() > ConstantArrayType::getMaxSizeBits(Info.Ctx)) { | |||
6704 | if (IsNothrow) { | |||
6705 | Result.setNull(Info.Ctx, E->getType()); | |||
6706 | return true; | |||
6707 | } | |||
6708 | ||||
6709 | Info.FFDiag(E, diag::note_constexpr_new_too_large) << APSInt(Size, true); | |||
6710 | return false; | |||
6711 | } | |||
6712 | ||||
6713 | QualType AllocType = Info.Ctx.getConstantArrayType(ElemType, Size, nullptr, | |||
6714 | ArrayType::Normal, 0); | |||
6715 | APValue *Val = Info.createHeapAlloc(E, AllocType, Result); | |||
6716 | *Val = APValue(APValue::UninitArray(), 0, Size.getZExtValue()); | |||
6717 | Result.addArray(Info, E, cast<ConstantArrayType>(AllocType)); | |||
6718 | return true; | |||
6719 | } | |||
6720 | ||||
6721 | static bool hasVirtualDestructor(QualType T) { | |||
6722 | if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) | |||
6723 | if (CXXDestructorDecl *DD = RD->getDestructor()) | |||
6724 | return DD->isVirtual(); | |||
6725 | return false; | |||
6726 | } | |||
6727 | ||||
6728 | static const FunctionDecl *getVirtualOperatorDelete(QualType T) { | |||
6729 | if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) | |||
6730 | if (CXXDestructorDecl *DD = RD->getDestructor()) | |||
6731 | return DD->isVirtual() ? DD->getOperatorDelete() : nullptr; | |||
6732 | return nullptr; | |||
6733 | } | |||
6734 | ||||
6735 | /// Check that the given object is a suitable pointer to a heap allocation that | |||
6736 | /// still exists and is of the right kind for the purpose of a deletion. | |||
6737 | /// | |||
6738 | /// On success, returns the heap allocation to deallocate. On failure, produces | |||
6739 | /// a diagnostic and returns std::nullopt. | |||
6740 | static std::optional<DynAlloc *> CheckDeleteKind(EvalInfo &Info, const Expr *E, | |||
6741 | const LValue &Pointer, | |||
6742 | DynAlloc::Kind DeallocKind) { | |||
6743 | auto PointerAsString = [&] { | |||
6744 | return Pointer.toString(Info.Ctx, Info.Ctx.VoidPtrTy); | |||
6745 | }; | |||
6746 | ||||
6747 | DynamicAllocLValue DA = Pointer.Base.dyn_cast<DynamicAllocLValue>(); | |||
6748 | if (!DA) { | |||
6749 | Info.FFDiag(E, diag::note_constexpr_delete_not_heap_alloc) | |||
6750 | << PointerAsString(); | |||
6751 | if (Pointer.Base) | |||
6752 | NoteLValueLocation(Info, Pointer.Base); | |||
6753 | return std::nullopt; | |||
6754 | } | |||
6755 | ||||
6756 | std::optional<DynAlloc *> Alloc = Info.lookupDynamicAlloc(DA); | |||
6757 | if (!Alloc) { | |||
6758 | Info.FFDiag(E, diag::note_constexpr_double_delete); | |||
6759 | return std::nullopt; | |||
6760 | } | |||
6761 | ||||
6762 | QualType AllocType = Pointer.Base.getDynamicAllocType(); | |||
6763 | if (DeallocKind != (*Alloc)->getKind()) { | |||
6764 | Info.FFDiag(E, diag::note_constexpr_new_delete_mismatch) | |||
6765 | << DeallocKind << (*Alloc)->getKind() << AllocType; | |||
6766 | NoteLValueLocation(Info, Pointer.Base); | |||
6767 | return std::nullopt; | |||
6768 | } | |||
6769 | ||||
6770 | bool Subobject = false; | |||
6771 | if (DeallocKind == DynAlloc::New) { | |||
6772 | Subobject = Pointer.Designator.MostDerivedPathLength != 0 || | |||
6773 | Pointer.Designator.isOnePastTheEnd(); | |||
6774 | } else { | |||
6775 | Subobject = Pointer.Designator.Entries.size() != 1 || | |||
6776 | Pointer.Designator.Entries[0].getAsArrayIndex() != 0; | |||
6777 | } | |||
6778 | if (Subobject) { | |||
6779 | Info.FFDiag(E, diag::note_constexpr_delete_subobject) | |||
6780 | << PointerAsString() << Pointer.Designator.isOnePastTheEnd(); | |||
6781 | return std::nullopt; | |||
6782 | } | |||
6783 | ||||
6784 | return Alloc; | |||
6785 | } | |||
6786 | ||||
6787 | // Perform a call to 'operator delete' or '__builtin_operator_delete'. | |||
6788 | bool HandleOperatorDeleteCall(EvalInfo &Info, const CallExpr *E) { | |||
6789 | if (Info.checkingPotentialConstantExpression() || | |||
6790 | Info.SpeculativeEvaluationDepth) | |||
6791 | return false; | |||
6792 | ||||
6793 | // This is permitted only within a call to std::allocator<T>::deallocate. | |||
6794 | if (!Info.getStdAllocatorCaller("deallocate")) { | |||
6795 | Info.FFDiag(E->getExprLoc()); | |||
6796 | return true; | |||
6797 | } | |||
6798 | ||||
6799 | LValue Pointer; | |||
6800 | if (!EvaluatePointer(E->getArg(0), Pointer, Info)) | |||
6801 | return false; | |||
6802 | for (unsigned I = 1, N = E->getNumArgs(); I != N; ++I) | |||
6803 | EvaluateIgnoredValue(Info, E->getArg(I)); | |||
6804 | ||||
6805 | if (Pointer.Designator.Invalid) | |||
6806 | return false; | |||
6807 | ||||
6808 | // Deleting a null pointer would have no effect, but it's not permitted by | |||
6809 | // std::allocator<T>::deallocate's contract. | |||
6810 | if (Pointer.isNullPointer()) { | |||
6811 | Info.CCEDiag(E->getExprLoc(), diag::note_constexpr_deallocate_null); | |||
6812 | return true; | |||
6813 | } | |||
6814 | ||||
6815 | if (!CheckDeleteKind(Info, E, Pointer, DynAlloc::StdAllocator)) | |||
6816 | return false; | |||
6817 | ||||
6818 | Info.HeapAllocs.erase(Pointer.Base.get<DynamicAllocLValue>()); | |||
6819 | return true; | |||
6820 | } | |||
6821 | ||||
6822 | //===----------------------------------------------------------------------===// | |||
6823 | // Generic Evaluation | |||
6824 | //===----------------------------------------------------------------------===// | |||
6825 | namespace { | |||
6826 | ||||
6827 | class BitCastBuffer { | |||
6828 | // FIXME: We're going to need bit-level granularity when we support | |||
6829 | // bit-fields. | |||
6830 | // FIXME: Its possible under the C++ standard for 'char' to not be 8 bits, but | |||
6831 | // we don't support a host or target where that is the case. Still, we should | |||
6832 | // use a more generic type in case we ever do. | |||
6833 | SmallVector<std::optional<unsigned char>, 32> Bytes; | |||
6834 | ||||
6835 | static_assert(std::numeric_limits<unsigned char>::digits >= 8, | |||
6836 | "Need at least 8 bit unsigned char"); | |||
6837 | ||||
6838 | bool TargetIsLittleEndian; | |||
6839 | ||||
6840 | public: | |||
6841 | BitCastBuffer(CharUnits Width, bool TargetIsLittleEndian) | |||
6842 | : Bytes(Width.getQuantity()), | |||
6843 | TargetIsLittleEndian(TargetIsLittleEndian) {} | |||
6844 | ||||
6845 | [[nodiscard]] bool readObject(CharUnits Offset, CharUnits Width, | |||
6846 | SmallVectorImpl<unsigned char> &Output) const { | |||
6847 | for (CharUnits I = Offset, E = Offset + Width; I != E; ++I) { | |||
6848 | // If a byte of an integer is uninitialized, then the whole integer is | |||
6849 | // uninitialized. | |||
6850 | if (!Bytes[I.getQuantity()]) | |||
6851 | return false; | |||
6852 | Output.push_back(*Bytes[I.getQuantity()]); | |||
6853 | } | |||
6854 | if (llvm::sys::IsLittleEndianHost != TargetIsLittleEndian) | |||
6855 | std::reverse(Output.begin(), Output.end()); | |||
6856 | return true; | |||
6857 | } | |||
6858 | ||||
6859 | void writeObject(CharUnits Offset, SmallVectorImpl<unsigned char> &Input) { | |||
6860 | if (llvm::sys::IsLittleEndianHost != TargetIsLittleEndian) | |||
6861 | std::reverse(Input.begin(), Input.end()); | |||
6862 | ||||
6863 | size_t Index = 0; | |||
6864 | for (unsigned char Byte : Input) { | |||
6865 | assert(!Bytes[Offset.getQuantity() + Index] && "overwriting a byte?")(static_cast <bool> (!Bytes[Offset.getQuantity() + Index ] && "overwriting a byte?") ? void (0) : __assert_fail ("!Bytes[Offset.getQuantity() + Index] && \"overwriting a byte?\"" , "clang/lib/AST/ExprConstant.cpp", 6865, __extension__ __PRETTY_FUNCTION__ )); | |||
6866 | Bytes[Offset.getQuantity() + Index] = Byte; | |||
6867 | ++Index; | |||
6868 | } | |||
6869 | } | |||
6870 | ||||
6871 | size_t size() { return Bytes.size(); } | |||
6872 | }; | |||
6873 | ||||
6874 | /// Traverse an APValue to produce an BitCastBuffer, emulating how the current | |||
6875 | /// target would represent the value at runtime. | |||
6876 | class APValueToBufferConverter { | |||
6877 | EvalInfo &Info; | |||
6878 | BitCastBuffer Buffer; | |||
6879 | const CastExpr *BCE; | |||
6880 | ||||
6881 | APValueToBufferConverter(EvalInfo &Info, CharUnits ObjectWidth, | |||
6882 | const CastExpr *BCE) | |||
6883 | : Info(Info), | |||
6884 | Buffer(ObjectWidth, Info.Ctx.getTargetInfo().isLittleEndian()), | |||
6885 | BCE(BCE) {} | |||
6886 | ||||
6887 | bool visit(const APValue &Val, QualType Ty) { | |||
6888 | return visit(Val, Ty, CharUnits::fromQuantity(0)); | |||
6889 | } | |||
6890 | ||||
6891 | // Write out Val with type Ty into Buffer starting at Offset. | |||
6892 | bool visit(const APValue &Val, QualType Ty, CharUnits Offset) { | |||
6893 | assert((size_t)Offset.getQuantity() <= Buffer.size())(static_cast <bool> ((size_t)Offset.getQuantity() <= Buffer.size()) ? void (0) : __assert_fail ("(size_t)Offset.getQuantity() <= Buffer.size()" , "clang/lib/AST/ExprConstant.cpp", 6893, __extension__ __PRETTY_FUNCTION__ )); | |||
6894 | ||||
6895 | // As a special case, nullptr_t has an indeterminate value. | |||
6896 | if (Ty->isNullPtrType()) | |||
6897 | return true; | |||
6898 | ||||
6899 | // Dig through Src to find the byte at SrcOffset. | |||
6900 | switch (Val.getKind()) { | |||
6901 | case APValue::Indeterminate: | |||
6902 | case APValue::None: | |||
6903 | return true; | |||
6904 | ||||
6905 | case APValue::Int: | |||
6906 | return visitInt(Val.getInt(), Ty, Offset); | |||
6907 | case APValue::Float: | |||
6908 | return visitFloat(Val.getFloat(), Ty, Offset); | |||
6909 | case APValue::Array: | |||
6910 | return visitArray(Val, Ty, Offset); | |||
6911 | case APValue::Struct: | |||
6912 | return visitRecord(Val, Ty, Offset); | |||
6913 | ||||
6914 | case APValue::ComplexInt: | |||
6915 | case APValue::ComplexFloat: | |||
6916 | case APValue::Vector: | |||
6917 | case APValue::FixedPoint: | |||
6918 | // FIXME: We should support these. | |||
6919 | ||||
6920 | case APValue::Union: | |||
6921 | case APValue::MemberPointer: | |||
6922 | case APValue::AddrLabelDiff: { | |||
6923 | Info.FFDiag(BCE->getBeginLoc(), | |||
6924 | diag::note_constexpr_bit_cast_unsupported_type) | |||
6925 | << Ty; | |||
6926 | return false; | |||
6927 | } | |||
6928 | ||||
6929 | case APValue::LValue: | |||
6930 | llvm_unreachable("LValue subobject in bit_cast?")::llvm::llvm_unreachable_internal("LValue subobject in bit_cast?" , "clang/lib/AST/ExprConstant.cpp", 6930); | |||
6931 | } | |||
6932 | llvm_unreachable("Unhandled APValue::ValueKind")::llvm::llvm_unreachable_internal("Unhandled APValue::ValueKind" , "clang/lib/AST/ExprConstant.cpp", 6932); | |||
6933 | } | |||
6934 | ||||
6935 | bool visitRecord(const APValue &Val, QualType Ty, CharUnits Offset) { | |||
6936 | const RecordDecl *RD = Ty->getAsRecordDecl(); | |||
6937 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
6938 | ||||
6939 | // Visit the base classes. | |||
6940 | if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) { | |||
6941 | for (size_t I = 0, E = CXXRD->getNumBases(); I != E; ++I) { | |||
6942 | const CXXBaseSpecifier &BS = CXXRD->bases_begin()[I]; | |||
6943 | CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl(); | |||
6944 | ||||
6945 | if (!visitRecord(Val.getStructBase(I), BS.getType(), | |||
6946 | Layout.getBaseClassOffset(BaseDecl) + Offset)) | |||
6947 | return false; | |||
6948 | } | |||
6949 | } | |||
6950 | ||||
6951 | // Visit the fields. | |||
6952 | unsigned FieldIdx = 0; | |||
6953 | for (FieldDecl *FD : RD->fields()) { | |||
6954 | if (FD->isBitField()) { | |||
6955 | Info.FFDiag(BCE->getBeginLoc(), | |||
6956 | diag::note_constexpr_bit_cast_unsupported_bitfield); | |||
6957 | return false; | |||
6958 | } | |||
6959 | ||||
6960 | uint64_t FieldOffsetBits = Layout.getFieldOffset(FieldIdx); | |||
6961 | ||||
6962 | assert(FieldOffsetBits % Info.Ctx.getCharWidth() == 0 &&(static_cast <bool> (FieldOffsetBits % Info.Ctx.getCharWidth () == 0 && "only bit-fields can have sub-char alignment" ) ? void (0) : __assert_fail ("FieldOffsetBits % Info.Ctx.getCharWidth() == 0 && \"only bit-fields can have sub-char alignment\"" , "clang/lib/AST/ExprConstant.cpp", 6963, __extension__ __PRETTY_FUNCTION__ )) | |||
6963 | "only bit-fields can have sub-char alignment")(static_cast <bool> (FieldOffsetBits % Info.Ctx.getCharWidth () == 0 && "only bit-fields can have sub-char alignment" ) ? void (0) : __assert_fail ("FieldOffsetBits % Info.Ctx.getCharWidth() == 0 && \"only bit-fields can have sub-char alignment\"" , "clang/lib/AST/ExprConstant.cpp", 6963, __extension__ __PRETTY_FUNCTION__ )); | |||
6964 | CharUnits FieldOffset = | |||
6965 | Info.Ctx.toCharUnitsFromBits(FieldOffsetBits) + Offset; | |||
6966 | QualType FieldTy = FD->getType(); | |||
6967 | if (!visit(Val.getStructField(FieldIdx), FieldTy, FieldOffset)) | |||
6968 | return false; | |||
6969 | ++FieldIdx; | |||
6970 | } | |||
6971 | ||||
6972 | return true; | |||
6973 | } | |||
6974 | ||||
6975 | bool visitArray(const APValue &Val, QualType Ty, CharUnits Offset) { | |||
6976 | const auto *CAT = | |||
6977 | dyn_cast_or_null<ConstantArrayType>(Ty->getAsArrayTypeUnsafe()); | |||
6978 | if (!CAT) | |||
6979 | return false; | |||
6980 | ||||
6981 | CharUnits ElemWidth = Info.Ctx.getTypeSizeInChars(CAT->getElementType()); | |||
6982 | unsigned NumInitializedElts = Val.getArrayInitializedElts(); | |||
6983 | unsigned ArraySize = Val.getArraySize(); | |||
6984 | // First, initialize the initialized elements. | |||
6985 | for (unsigned I = 0; I != NumInitializedElts; ++I) { | |||
6986 | const APValue &SubObj = Val.getArrayInitializedElt(I); | |||
6987 | if (!visit(SubObj, CAT->getElementType(), Offset + I * ElemWidth)) | |||
6988 | return false; | |||
6989 | } | |||
6990 | ||||
6991 | // Next, initialize the rest of the array using the filler. | |||
6992 | if (Val.hasArrayFiller()) { | |||
6993 | const APValue &Filler = Val.getArrayFiller(); | |||
6994 | for (unsigned I = NumInitializedElts; I != ArraySize; ++I) { | |||
6995 | if (!visit(Filler, CAT->getElementType(), Offset + I * ElemWidth)) | |||
6996 | return false; | |||
6997 | } | |||
6998 | } | |||
6999 | ||||
7000 | return true; | |||
7001 | } | |||
7002 | ||||
7003 | bool visitInt(const APSInt &Val, QualType Ty, CharUnits Offset) { | |||
7004 | APSInt AdjustedVal = Val; | |||
7005 | unsigned Width = AdjustedVal.getBitWidth(); | |||
7006 | if (Ty->isBooleanType()) { | |||
7007 | Width = Info.Ctx.getTypeSize(Ty); | |||
7008 | AdjustedVal = AdjustedVal.extend(Width); | |||
7009 | } | |||
7010 | ||||
7011 | SmallVector<unsigned char, 8> Bytes(Width / 8); | |||
7012 | llvm::StoreIntToMemory(AdjustedVal, &*Bytes.begin(), Width / 8); | |||
7013 | Buffer.writeObject(Offset, Bytes); | |||
7014 | return true; | |||
7015 | } | |||
7016 | ||||
7017 | bool visitFloat(const APFloat &Val, QualType Ty, CharUnits Offset) { | |||
7018 | APSInt AsInt(Val.bitcastToAPInt()); | |||
7019 | return visitInt(AsInt, Ty, Offset); | |||
7020 | } | |||
7021 | ||||
7022 | public: | |||
7023 | static std::optional<BitCastBuffer> | |||
7024 | convert(EvalInfo &Info, const APValue &Src, const CastExpr *BCE) { | |||
7025 | CharUnits DstSize = Info.Ctx.getTypeSizeInChars(BCE->getType()); | |||
7026 | APValueToBufferConverter Converter(Info, DstSize, BCE); | |||
7027 | if (!Converter.visit(Src, BCE->getSubExpr()->getType())) | |||
7028 | return std::nullopt; | |||
7029 | return Converter.Buffer; | |||
7030 | } | |||
7031 | }; | |||
7032 | ||||
7033 | /// Write an BitCastBuffer into an APValue. | |||
7034 | class BufferToAPValueConverter { | |||
7035 | EvalInfo &Info; | |||
7036 | const BitCastBuffer &Buffer; | |||
7037 | const CastExpr *BCE; | |||
7038 | ||||
7039 | BufferToAPValueConverter(EvalInfo &Info, const BitCastBuffer &Buffer, | |||
7040 | const CastExpr *BCE) | |||
7041 | : Info(Info), Buffer(Buffer), BCE(BCE) {} | |||
7042 | ||||
7043 | // Emit an unsupported bit_cast type error. Sema refuses to build a bit_cast | |||
7044 | // with an invalid type, so anything left is a deficiency on our part (FIXME). | |||
7045 | // Ideally this will be unreachable. | |||
7046 | std::nullopt_t unsupportedType(QualType Ty) { | |||
7047 | Info.FFDiag(BCE->getBeginLoc(), | |||
7048 | diag::note_constexpr_bit_cast_unsupported_type) | |||
7049 | << Ty; | |||
7050 | return std::nullopt; | |||
7051 | } | |||
7052 | ||||
7053 | std::nullopt_t unrepresentableValue(QualType Ty, const APSInt &Val) { | |||
7054 | Info.FFDiag(BCE->getBeginLoc(), | |||
7055 | diag::note_constexpr_bit_cast_unrepresentable_value) | |||
7056 | << Ty << toString(Val, /*Radix=*/10); | |||
7057 | return std::nullopt; | |||
7058 | } | |||
7059 | ||||
7060 | std::optional<APValue> visit(const BuiltinType *T, CharUnits Offset, | |||
7061 | const EnumType *EnumSugar = nullptr) { | |||
7062 | if (T->isNullPtrType()) { | |||
7063 | uint64_t NullValue = Info.Ctx.getTargetNullPointerValue(QualType(T, 0)); | |||
7064 | return APValue((Expr *)nullptr, | |||
7065 | /*Offset=*/CharUnits::fromQuantity(NullValue), | |||
7066 | APValue::NoLValuePath{}, /*IsNullPtr=*/true); | |||
7067 | } | |||
7068 | ||||
7069 | CharUnits SizeOf = Info.Ctx.getTypeSizeInChars(T); | |||
7070 | ||||
7071 | // Work around floating point types that contain unused padding bytes. This | |||
7072 | // is really just `long double` on x86, which is the only fundamental type | |||
7073 | // with padding bytes. | |||
7074 | if (T->isRealFloatingType()) { | |||
7075 | const llvm::fltSemantics &Semantics = | |||
7076 | Info.Ctx.getFloatTypeSemantics(QualType(T, 0)); | |||
7077 | unsigned NumBits = llvm::APFloatBase::getSizeInBits(Semantics); | |||
7078 | assert(NumBits % 8 == 0)(static_cast <bool> (NumBits % 8 == 0) ? void (0) : __assert_fail ("NumBits % 8 == 0", "clang/lib/AST/ExprConstant.cpp", 7078, __extension__ __PRETTY_FUNCTION__)); | |||
7079 | CharUnits NumBytes = CharUnits::fromQuantity(NumBits / 8); | |||
7080 | if (NumBytes != SizeOf) | |||
7081 | SizeOf = NumBytes; | |||
7082 | } | |||
7083 | ||||
7084 | SmallVector<uint8_t, 8> Bytes; | |||
7085 | if (!Buffer.readObject(Offset, SizeOf, Bytes)) { | |||
7086 | // If this is std::byte or unsigned char, then its okay to store an | |||
7087 | // indeterminate value. | |||
7088 | bool IsStdByte = EnumSugar && EnumSugar->isStdByteType(); | |||
7089 | bool IsUChar = | |||
7090 | !EnumSugar && (T->isSpecificBuiltinType(BuiltinType::UChar) || | |||
7091 | T->isSpecificBuiltinType(BuiltinType::Char_U)); | |||
7092 | if (!IsStdByte && !IsUChar) { | |||
7093 | QualType DisplayType(EnumSugar ? (const Type *)EnumSugar : T, 0); | |||
7094 | Info.FFDiag(BCE->getExprLoc(), | |||
7095 | diag::note_constexpr_bit_cast_indet_dest) | |||
7096 | << DisplayType << Info.Ctx.getLangOpts().CharIsSigned; | |||
7097 | return std::nullopt; | |||
7098 | } | |||
7099 | ||||
7100 | return APValue::IndeterminateValue(); | |||
7101 | } | |||
7102 | ||||
7103 | APSInt Val(SizeOf.getQuantity() * Info.Ctx.getCharWidth(), true); | |||
7104 | llvm::LoadIntFromMemory(Val, &*Bytes.begin(), Bytes.size()); | |||
7105 | ||||
7106 | if (T->isIntegralOrEnumerationType()) { | |||
7107 | Val.setIsSigned(T->isSignedIntegerOrEnumerationType()); | |||
7108 | ||||
7109 | unsigned IntWidth = Info.Ctx.getIntWidth(QualType(T, 0)); | |||
7110 | if (IntWidth != Val.getBitWidth()) { | |||
7111 | APSInt Truncated = Val.trunc(IntWidth); | |||
7112 | if (Truncated.extend(Val.getBitWidth()) != Val) | |||
7113 | return unrepresentableValue(QualType(T, 0), Val); | |||
7114 | Val = Truncated; | |||
7115 | } | |||
7116 | ||||
7117 | return APValue(Val); | |||
7118 | } | |||
7119 | ||||
7120 | if (T->isRealFloatingType()) { | |||
7121 | const llvm::fltSemantics &Semantics = | |||
7122 | Info.Ctx.getFloatTypeSemantics(QualType(T, 0)); | |||
7123 | return APValue(APFloat(Semantics, Val)); | |||
7124 | } | |||
7125 | ||||
7126 | return unsupportedType(QualType(T, 0)); | |||
7127 | } | |||
7128 | ||||
7129 | std::optional<APValue> visit(const RecordType *RTy, CharUnits Offset) { | |||
7130 | const RecordDecl *RD = RTy->getAsRecordDecl(); | |||
7131 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
7132 | ||||
7133 | unsigned NumBases = 0; | |||
7134 | if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) | |||
7135 | NumBases = CXXRD->getNumBases(); | |||
7136 | ||||
7137 | APValue ResultVal(APValue::UninitStruct(), NumBases, | |||
7138 | std::distance(RD->field_begin(), RD->field_end())); | |||
7139 | ||||
7140 | // Visit the base classes. | |||
7141 | if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) { | |||
7142 | for (size_t I = 0, E = CXXRD->getNumBases(); I != E; ++I) { | |||
7143 | const CXXBaseSpecifier &BS = CXXRD->bases_begin()[I]; | |||
7144 | CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl(); | |||
7145 | if (BaseDecl->isEmpty() || | |||
7146 | Info.Ctx.getASTRecordLayout(BaseDecl).getNonVirtualSize().isZero()) | |||
7147 | continue; | |||
7148 | ||||
7149 | std::optional<APValue> SubObj = visitType( | |||
7150 | BS.getType(), Layout.getBaseClassOffset(BaseDecl) + Offset); | |||
7151 | if (!SubObj) | |||
7152 | return std::nullopt; | |||
7153 | ResultVal.getStructBase(I) = *SubObj; | |||
7154 | } | |||
7155 | } | |||
7156 | ||||
7157 | // Visit the fields. | |||
7158 | unsigned FieldIdx = 0; | |||
7159 | for (FieldDecl *FD : RD->fields()) { | |||
7160 | // FIXME: We don't currently support bit-fields. A lot of the logic for | |||
7161 | // this is in CodeGen, so we need to factor it around. | |||
7162 | if (FD->isBitField()) { | |||
7163 | Info.FFDiag(BCE->getBeginLoc(), | |||
7164 | diag::note_constexpr_bit_cast_unsupported_bitfield); | |||
7165 | return std::nullopt; | |||
7166 | } | |||
7167 | ||||
7168 | uint64_t FieldOffsetBits = Layout.getFieldOffset(FieldIdx); | |||
7169 | assert(FieldOffsetBits % Info.Ctx.getCharWidth() == 0)(static_cast <bool> (FieldOffsetBits % Info.Ctx.getCharWidth () == 0) ? void (0) : __assert_fail ("FieldOffsetBits % Info.Ctx.getCharWidth() == 0" , "clang/lib/AST/ExprConstant.cpp", 7169, __extension__ __PRETTY_FUNCTION__ )); | |||
7170 | ||||
7171 | CharUnits FieldOffset = | |||
7172 | CharUnits::fromQuantity(FieldOffsetBits / Info.Ctx.getCharWidth()) + | |||
7173 | Offset; | |||
7174 | QualType FieldTy = FD->getType(); | |||
7175 | std::optional<APValue> SubObj = visitType(FieldTy, FieldOffset); | |||
7176 | if (!SubObj) | |||
7177 | return std::nullopt; | |||
7178 | ResultVal.getStructField(FieldIdx) = *SubObj; | |||
7179 | ++FieldIdx; | |||
7180 | } | |||
7181 | ||||
7182 | return ResultVal; | |||
7183 | } | |||
7184 | ||||
7185 | std::optional<APValue> visit(const EnumType *Ty, CharUnits Offset) { | |||
7186 | QualType RepresentationType = Ty->getDecl()->getIntegerType(); | |||
7187 | assert(!RepresentationType.isNull() &&(static_cast <bool> (!RepresentationType.isNull() && "enum forward decl should be caught by Sema") ? void (0) : __assert_fail ("!RepresentationType.isNull() && \"enum forward decl should be caught by Sema\"" , "clang/lib/AST/ExprConstant.cpp", 7188, __extension__ __PRETTY_FUNCTION__ )) | |||
7188 | "enum forward decl should be caught by Sema")(static_cast <bool> (!RepresentationType.isNull() && "enum forward decl should be caught by Sema") ? void (0) : __assert_fail ("!RepresentationType.isNull() && \"enum forward decl should be caught by Sema\"" , "clang/lib/AST/ExprConstant.cpp", 7188, __extension__ __PRETTY_FUNCTION__ )); | |||
7189 | const auto *AsBuiltin = | |||
7190 | RepresentationType.getCanonicalType()->castAs<BuiltinType>(); | |||
7191 | // Recurse into the underlying type. Treat std::byte transparently as | |||
7192 | // unsigned char. | |||
7193 | return visit(AsBuiltin, Offset, /*EnumTy=*/Ty); | |||
7194 | } | |||
7195 | ||||
7196 | std::optional<APValue> visit(const ConstantArrayType *Ty, CharUnits Offset) { | |||
7197 | size_t Size = Ty->getSize().getLimitedValue(); | |||
7198 | CharUnits ElementWidth = Info.Ctx.getTypeSizeInChars(Ty->getElementType()); | |||
7199 | ||||
7200 | APValue ArrayValue(APValue::UninitArray(), Size, Size); | |||
7201 | for (size_t I = 0; I != Size; ++I) { | |||
7202 | std::optional<APValue> ElementValue = | |||
7203 | visitType(Ty->getElementType(), Offset + I * ElementWidth); | |||
7204 | if (!ElementValue) | |||
7205 | return std::nullopt; | |||
7206 | ArrayValue.getArrayInitializedElt(I) = std::move(*ElementValue); | |||
7207 | } | |||
7208 | ||||
7209 | return ArrayValue; | |||
7210 | } | |||
7211 | ||||
7212 | std::optional<APValue> visit(const Type *Ty, CharUnits Offset) { | |||
7213 | return unsupportedType(QualType(Ty, 0)); | |||
7214 | } | |||
7215 | ||||
7216 | std::optional<APValue> visitType(QualType Ty, CharUnits Offset) { | |||
7217 | QualType Can = Ty.getCanonicalType(); | |||
7218 | ||||
7219 | switch (Can->getTypeClass()) { | |||
7220 | #define TYPE(Class, Base) \ | |||
7221 | case Type::Class: \ | |||
7222 | return visit(cast<Class##Type>(Can.getTypePtr()), Offset); | |||
7223 | #define ABSTRACT_TYPE(Class, Base) | |||
7224 | #define NON_CANONICAL_TYPE(Class, Base) \ | |||
7225 | case Type::Class: \ | |||
7226 | llvm_unreachable("non-canonical type should be impossible!")::llvm::llvm_unreachable_internal("non-canonical type should be impossible!" , "clang/lib/AST/ExprConstant.cpp", 7226); | |||
7227 | #define DEPENDENT_TYPE(Class, Base) \ | |||
7228 | case Type::Class: \ | |||
7229 | llvm_unreachable( \::llvm::llvm_unreachable_internal("dependent types aren't supported in the constant evaluator!" , "clang/lib/AST/ExprConstant.cpp", 7230) | |||
7230 | "dependent types aren't supported in the constant evaluator!")::llvm::llvm_unreachable_internal("dependent types aren't supported in the constant evaluator!" , "clang/lib/AST/ExprConstant.cpp", 7230); | |||
7231 | #define NON_CANONICAL_UNLESS_DEPENDENT(Class, Base)case Type::Class: ::llvm::llvm_unreachable_internal("either dependent or not canonical!" , "clang/lib/AST/ExprConstant.cpp", 7231); \ | |||
7232 | case Type::Class: \ | |||
7233 | llvm_unreachable("either dependent or not canonical!")::llvm::llvm_unreachable_internal("either dependent or not canonical!" , "clang/lib/AST/ExprConstant.cpp", 7233); | |||
7234 | #include "clang/AST/TypeNodes.inc" | |||
7235 | } | |||
7236 | llvm_unreachable("Unhandled Type::TypeClass")::llvm::llvm_unreachable_internal("Unhandled Type::TypeClass" , "clang/lib/AST/ExprConstant.cpp", 7236); | |||
7237 | } | |||
7238 | ||||
7239 | public: | |||
7240 | // Pull out a full value of type DstType. | |||
7241 | static std::optional<APValue> convert(EvalInfo &Info, BitCastBuffer &Buffer, | |||
7242 | const CastExpr *BCE) { | |||
7243 | BufferToAPValueConverter Converter(Info, Buffer, BCE); | |||
7244 | return Converter.visitType(BCE->getType(), CharUnits::fromQuantity(0)); | |||
7245 | } | |||
7246 | }; | |||
7247 | ||||
7248 | static bool checkBitCastConstexprEligibilityType(SourceLocation Loc, | |||
7249 | QualType Ty, EvalInfo *Info, | |||
7250 | const ASTContext &Ctx, | |||
7251 | bool CheckingDest) { | |||
7252 | Ty = Ty.getCanonicalType(); | |||
7253 | ||||
7254 | auto diag = [&](int Reason) { | |||
7255 | if (Info) | |||
7256 | Info->FFDiag(Loc, diag::note_constexpr_bit_cast_invalid_type) | |||
7257 | << CheckingDest << (Reason == 4) << Reason; | |||
7258 | return false; | |||
7259 | }; | |||
7260 | auto note = [&](int Construct, QualType NoteTy, SourceLocation NoteLoc) { | |||
7261 | if (Info) | |||
7262 | Info->Note(NoteLoc, diag::note_constexpr_bit_cast_invalid_subtype) | |||
7263 | << NoteTy << Construct << Ty; | |||
7264 | return false; | |||
7265 | }; | |||
7266 | ||||
7267 | if (Ty->isUnionType()) | |||
7268 | return diag(0); | |||
7269 | if (Ty->isPointerType()) | |||
7270 | return diag(1); | |||
7271 | if (Ty->isMemberPointerType()) | |||
7272 | return diag(2); | |||
7273 | if (Ty.isVolatileQualified()) | |||
7274 | return diag(3); | |||
7275 | ||||
7276 | if (RecordDecl *Record = Ty->getAsRecordDecl()) { | |||
7277 | if (auto *CXXRD = dyn_cast<CXXRecordDecl>(Record)) { | |||
7278 | for (CXXBaseSpecifier &BS : CXXRD->bases()) | |||
7279 | if (!checkBitCastConstexprEligibilityType(Loc, BS.getType(), Info, Ctx, | |||
7280 | CheckingDest)) | |||
7281 | return note(1, BS.getType(), BS.getBeginLoc()); | |||
7282 | } | |||
7283 | for (FieldDecl *FD : Record->fields()) { | |||
7284 | if (FD->getType()->isReferenceType()) | |||
7285 | return diag(4); | |||
7286 | if (!checkBitCastConstexprEligibilityType(Loc, FD->getType(), Info, Ctx, | |||
7287 | CheckingDest)) | |||
7288 | return note(0, FD->getType(), FD->getBeginLoc()); | |||
7289 | } | |||
7290 | } | |||
7291 | ||||
7292 | if (Ty->isArrayType() && | |||
7293 | !checkBitCastConstexprEligibilityType(Loc, Ctx.getBaseElementType(Ty), | |||
7294 | Info, Ctx, CheckingDest)) | |||
7295 | return false; | |||
7296 | ||||
7297 | return true; | |||
7298 | } | |||
7299 | ||||
7300 | static bool checkBitCastConstexprEligibility(EvalInfo *Info, | |||
7301 | const ASTContext &Ctx, | |||
7302 | const CastExpr *BCE) { | |||
7303 | bool DestOK = checkBitCastConstexprEligibilityType( | |||
7304 | BCE->getBeginLoc(), BCE->getType(), Info, Ctx, true); | |||
7305 | bool SourceOK = DestOK && checkBitCastConstexprEligibilityType( | |||
7306 | BCE->getBeginLoc(), | |||
7307 | BCE->getSubExpr()->getType(), Info, Ctx, false); | |||
7308 | return SourceOK; | |||
7309 | } | |||
7310 | ||||
7311 | static bool handleLValueToRValueBitCast(EvalInfo &Info, APValue &DestValue, | |||
7312 | APValue &SourceValue, | |||
7313 | const CastExpr *BCE) { | |||
7314 | assert(CHAR_BIT == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 &&(static_cast <bool> (8 == 8 && Info.Ctx.getTargetInfo ().getCharWidth() == 8 && "no host or target supports non 8-bit chars" ) ? void (0) : __assert_fail ("CHAR_BIT == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 && \"no host or target supports non 8-bit chars\"" , "clang/lib/AST/ExprConstant.cpp", 7315, __extension__ __PRETTY_FUNCTION__ )) | |||
7315 | "no host or target supports non 8-bit chars")(static_cast <bool> (8 == 8 && Info.Ctx.getTargetInfo ().getCharWidth() == 8 && "no host or target supports non 8-bit chars" ) ? void (0) : __assert_fail ("CHAR_BIT == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 && \"no host or target supports non 8-bit chars\"" , "clang/lib/AST/ExprConstant.cpp", 7315, __extension__ __PRETTY_FUNCTION__ )); | |||
7316 | assert(SourceValue.isLValue() &&(static_cast <bool> (SourceValue.isLValue() && "LValueToRValueBitcast requires an lvalue operand!" ) ? void (0) : __assert_fail ("SourceValue.isLValue() && \"LValueToRValueBitcast requires an lvalue operand!\"" , "clang/lib/AST/ExprConstant.cpp", 7317, __extension__ __PRETTY_FUNCTION__ )) | |||
7317 | "LValueToRValueBitcast requires an lvalue operand!")(static_cast <bool> (SourceValue.isLValue() && "LValueToRValueBitcast requires an lvalue operand!" ) ? void (0) : __assert_fail ("SourceValue.isLValue() && \"LValueToRValueBitcast requires an lvalue operand!\"" , "clang/lib/AST/ExprConstant.cpp", 7317, __extension__ __PRETTY_FUNCTION__ )); | |||
7318 | ||||
7319 | if (!checkBitCastConstexprEligibility(&Info, Info.Ctx, BCE)) | |||
7320 | return false; | |||
7321 | ||||
7322 | LValue SourceLValue; | |||
7323 | APValue SourceRValue; | |||
7324 | SourceLValue.setFrom(Info.Ctx, SourceValue); | |||
7325 | if (!handleLValueToRValueConversion( | |||
7326 | Info, BCE, BCE->getSubExpr()->getType().withConst(), SourceLValue, | |||
7327 | SourceRValue, /*WantObjectRepresentation=*/true)) | |||
7328 | return false; | |||
7329 | ||||
7330 | // Read out SourceValue into a char buffer. | |||
7331 | std::optional<BitCastBuffer> Buffer = | |||
7332 | APValueToBufferConverter::convert(Info, SourceRValue, BCE); | |||
7333 | if (!Buffer) | |||
7334 | return false; | |||
7335 | ||||
7336 | // Write out the buffer into a new APValue. | |||
7337 | std::optional<APValue> MaybeDestValue = | |||
7338 | BufferToAPValueConverter::convert(Info, *Buffer, BCE); | |||
7339 | if (!MaybeDestValue) | |||
7340 | return false; | |||
7341 | ||||
7342 | DestValue = std::move(*MaybeDestValue); | |||
7343 | return true; | |||
7344 | } | |||
7345 | ||||
7346 | template <class Derived> | |||
7347 | class ExprEvaluatorBase | |||
7348 | : public ConstStmtVisitor<Derived, bool> { | |||
7349 | private: | |||
7350 | Derived &getDerived() { return static_cast<Derived&>(*this); } | |||
7351 | bool DerivedSuccess(const APValue &V, const Expr *E) { | |||
7352 | return getDerived().Success(V, E); | |||
7353 | } | |||
7354 | bool DerivedZeroInitialization(const Expr *E) { | |||
7355 | return getDerived().ZeroInitialization(E); | |||
7356 | } | |||
7357 | ||||
7358 | // Check whether a conditional operator with a non-constant condition is a | |||
7359 | // potential constant expression. If neither arm is a potential constant | |||
7360 | // expression, then the conditional operator is not either. | |||
7361 | template<typename ConditionalOperator> | |||
7362 | void CheckPotentialConstantConditional(const ConditionalOperator *E) { | |||
7363 | assert(Info.checkingPotentialConstantExpression())(static_cast <bool> (Info.checkingPotentialConstantExpression ()) ? void (0) : __assert_fail ("Info.checkingPotentialConstantExpression()" , "clang/lib/AST/ExprConstant.cpp", 7363, __extension__ __PRETTY_FUNCTION__ )); | |||
7364 | ||||
7365 | // Speculatively evaluate both arms. | |||
7366 | SmallVector<PartialDiagnosticAt, 8> Diag; | |||
7367 | { | |||
7368 | SpeculativeEvaluationRAII Speculate(Info, &Diag); | |||
7369 | StmtVisitorTy::Visit(E->getFalseExpr()); | |||
7370 | if (Diag.empty()) | |||
7371 | return; | |||
7372 | } | |||
7373 | ||||
7374 | { | |||
7375 | SpeculativeEvaluationRAII Speculate(Info, &Diag); | |||
7376 | Diag.clear(); | |||
7377 | StmtVisitorTy::Visit(E->getTrueExpr()); | |||
7378 | if (Diag.empty()) | |||
7379 | return; | |||
7380 | } | |||
7381 | ||||
7382 | Error(E, diag::note_constexpr_conditional_never_const); | |||
7383 | } | |||
7384 | ||||
7385 | ||||
7386 | template<typename ConditionalOperator> | |||
7387 | bool HandleConditionalOperator(const ConditionalOperator *E) { | |||
7388 | bool BoolResult; | |||
7389 | if (!EvaluateAsBooleanCondition(E->getCond(), BoolResult, Info)) { | |||
7390 | if (Info.checkingPotentialConstantExpression() && Info.noteFailure()) { | |||
7391 | CheckPotentialConstantConditional(E); | |||
7392 | return false; | |||
7393 | } | |||
7394 | if (Info.noteFailure()) { | |||
7395 | StmtVisitorTy::Visit(E->getTrueExpr()); | |||
7396 | StmtVisitorTy::Visit(E->getFalseExpr()); | |||
7397 | } | |||
7398 | return false; | |||
7399 | } | |||
7400 | ||||
7401 | Expr *EvalExpr = BoolResult ? E->getTrueExpr() : E->getFalseExpr(); | |||
7402 | return StmtVisitorTy::Visit(EvalExpr); | |||
7403 | } | |||
7404 | ||||
7405 | protected: | |||
7406 | EvalInfo &Info; | |||
7407 | typedef ConstStmtVisitor<Derived, bool> StmtVisitorTy; | |||
7408 | typedef ExprEvaluatorBase ExprEvaluatorBaseTy; | |||
7409 | ||||
7410 | OptionalDiagnostic CCEDiag(const Expr *E, diag::kind D) { | |||
7411 | return Info.CCEDiag(E, D); | |||
7412 | } | |||
7413 | ||||
7414 | bool ZeroInitialization(const Expr *E) { return Error(E); } | |||
7415 | ||||
7416 | bool IsConstantEvaluatedBuiltinCall(const CallExpr *E) { | |||
7417 | unsigned BuiltinOp = E->getBuiltinCallee(); | |||
7418 | return BuiltinOp != 0 && | |||
7419 | Info.Ctx.BuiltinInfo.isConstantEvaluated(BuiltinOp); | |||
7420 | } | |||
7421 | ||||
7422 | public: | |||
7423 | ExprEvaluatorBase(EvalInfo &Info) : Info(Info) {} | |||
7424 | ||||
7425 | EvalInfo &getEvalInfo() { return Info; } | |||
7426 | ||||
7427 | /// Report an evaluation error. This should only be called when an error is | |||
7428 | /// first discovered. When propagating an error, just return false. | |||
7429 | bool Error(const Expr *E, diag::kind D) { | |||
7430 | Info.FFDiag(E, D); | |||
7431 | return false; | |||
7432 | } | |||
7433 | bool Error(const Expr *E) { | |||
7434 | return Error(E, diag::note_invalid_subexpr_in_const_expr); | |||
7435 | } | |||
7436 | ||||
7437 | bool VisitStmt(const Stmt *) { | |||
7438 | llvm_unreachable("Expression evaluator should not be called on stmts")::llvm::llvm_unreachable_internal("Expression evaluator should not be called on stmts" , "clang/lib/AST/ExprConstant.cpp", 7438); | |||
7439 | } | |||
7440 | bool VisitExpr(const Expr *E) { | |||
7441 | return Error(E); | |||
7442 | } | |||
7443 | ||||
7444 | bool VisitConstantExpr(const ConstantExpr *E) { | |||
7445 | if (E->hasAPValueResult()) | |||
7446 | return DerivedSuccess(E->getAPValueResult(), E); | |||
7447 | ||||
7448 | return StmtVisitorTy::Visit(E->getSubExpr()); | |||
7449 | } | |||
7450 | ||||
7451 | bool VisitParenExpr(const ParenExpr *E) | |||
7452 | { return StmtVisitorTy::Visit(E->getSubExpr()); } | |||
7453 | bool VisitUnaryExtension(const UnaryOperator *E) | |||
7454 | { return StmtVisitorTy::Visit(E->getSubExpr()); } | |||
7455 | bool VisitUnaryPlus(const UnaryOperator *E) | |||
7456 | { return StmtVisitorTy::Visit(E->getSubExpr()); } | |||
7457 | bool VisitChooseExpr(const ChooseExpr *E) | |||
7458 | { return StmtVisitorTy::Visit(E->getChosenSubExpr()); } | |||
7459 | bool VisitGenericSelectionExpr(const GenericSelectionExpr *E) | |||
7460 | { return StmtVisitorTy::Visit(E->getResultExpr()); } | |||
7461 | bool VisitSubstNonTypeTemplateParmExpr(const SubstNonTypeTemplateParmExpr *E) | |||
7462 | { return StmtVisitorTy::Visit(E->getReplacement()); } | |||
7463 | bool VisitCXXDefaultArgExpr(const CXXDefaultArgExpr *E) { | |||
7464 | TempVersionRAII RAII(*Info.CurrentCall); | |||
7465 | SourceLocExprScopeGuard Guard(E, Info.CurrentCall->CurSourceLocExprScope); | |||
7466 | return StmtVisitorTy::Visit(E->getExpr()); | |||
7467 | } | |||
7468 | bool VisitCXXDefaultInitExpr(const CXXDefaultInitExpr *E) { | |||
7469 | TempVersionRAII RAII(*Info.CurrentCall); | |||
7470 | // The initializer may not have been parsed yet, or might be erroneous. | |||
7471 | if (!E->getExpr()) | |||
7472 | return Error(E); | |||
7473 | SourceLocExprScopeGuard Guard(E, Info.CurrentCall->CurSourceLocExprScope); | |||
7474 | return StmtVisitorTy::Visit(E->getExpr()); | |||
7475 | } | |||
7476 | ||||
7477 | bool VisitExprWithCleanups(const ExprWithCleanups *E) { | |||
7478 | FullExpressionRAII Scope(Info); | |||
7479 | return StmtVisitorTy::Visit(E->getSubExpr()) && Scope.destroy(); | |||
7480 | } | |||
7481 | ||||
7482 | // Temporaries are registered when created, so we don't care about | |||
7483 | // CXXBindTemporaryExpr. | |||
7484 | bool VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *E) { | |||
7485 | return StmtVisitorTy::Visit(E->getSubExpr()); | |||
7486 | } | |||
7487 | ||||
7488 | bool VisitCXXReinterpretCastExpr(const CXXReinterpretCastExpr *E) { | |||
7489 | CCEDiag(E, diag::note_constexpr_invalid_cast) << 0; | |||
7490 | return static_cast<Derived*>(this)->VisitCastExpr(E); | |||
7491 | } | |||
7492 | bool VisitCXXDynamicCastExpr(const CXXDynamicCastExpr *E) { | |||
7493 | if (!Info.Ctx.getLangOpts().CPlusPlus20) | |||
7494 | CCEDiag(E, diag::note_constexpr_invalid_cast) << 1; | |||
7495 | return static_cast<Derived*>(this)->VisitCastExpr(E); | |||
7496 | } | |||
7497 | bool VisitBuiltinBitCastExpr(const BuiltinBitCastExpr *E) { | |||
7498 | return static_cast<Derived*>(this)->VisitCastExpr(E); | |||
7499 | } | |||
7500 | ||||
7501 | bool VisitBinaryOperator(const BinaryOperator *E) { | |||
7502 | switch (E->getOpcode()) { | |||
7503 | default: | |||
7504 | return Error(E); | |||
7505 | ||||
7506 | case BO_Comma: | |||
7507 | VisitIgnoredValue(E->getLHS()); | |||
7508 | return StmtVisitorTy::Visit(E->getRHS()); | |||
7509 | ||||
7510 | case BO_PtrMemD: | |||
7511 | case BO_PtrMemI: { | |||
7512 | LValue Obj; | |||
7513 | if (!HandleMemberPointerAccess(Info, E, Obj)) | |||
7514 | return false; | |||
7515 | APValue Result; | |||
7516 | if (!handleLValueToRValueConversion(Info, E, E->getType(), Obj, Result)) | |||
7517 | return false; | |||
7518 | return DerivedSuccess(Result, E); | |||
7519 | } | |||
7520 | } | |||
7521 | } | |||
7522 | ||||
7523 | bool VisitCXXRewrittenBinaryOperator(const CXXRewrittenBinaryOperator *E) { | |||
7524 | return StmtVisitorTy::Visit(E->getSemanticForm()); | |||
7525 | } | |||
7526 | ||||
7527 | bool VisitBinaryConditionalOperator(const BinaryConditionalOperator *E) { | |||
7528 | // Evaluate and cache the common expression. We treat it as a temporary, | |||
7529 | // even though it's not quite the same thing. | |||
7530 | LValue CommonLV; | |||
7531 | if (!Evaluate(Info.CurrentCall->createTemporary( | |||
7532 | E->getOpaqueValue(), | |||
7533 | getStorageType(Info.Ctx, E->getOpaqueValue()), | |||
7534 | ScopeKind::FullExpression, CommonLV), | |||
7535 | Info, E->getCommon())) | |||
7536 | return false; | |||
7537 | ||||
7538 | return HandleConditionalOperator(E); | |||
7539 | } | |||
7540 | ||||
7541 | bool VisitConditionalOperator(const ConditionalOperator *E) { | |||
7542 | bool IsBcpCall = false; | |||
7543 | // If the condition (ignoring parens) is a __builtin_constant_p call, | |||
7544 | // the result is a constant expression if it can be folded without | |||
7545 | // side-effects. This is an important GNU extension. See GCC PR38377 | |||
7546 | // for discussion. | |||
7547 | if (const CallExpr *CallCE = | |||
7548 | dyn_cast<CallExpr>(E->getCond()->IgnoreParenCasts())) | |||
7549 | if (CallCE->getBuiltinCallee() == Builtin::BI__builtin_constant_p) | |||
7550 | IsBcpCall = true; | |||
7551 | ||||
7552 | // Always assume __builtin_constant_p(...) ? ... : ... is a potential | |||
7553 | // constant expression; we can't check whether it's potentially foldable. | |||
7554 | // FIXME: We should instead treat __builtin_constant_p as non-constant if | |||
7555 | // it would return 'false' in this mode. | |||
7556 | if (Info.checkingPotentialConstantExpression() && IsBcpCall) | |||
7557 | return false; | |||
7558 | ||||
7559 | FoldConstant Fold(Info, IsBcpCall); | |||
7560 | if (!HandleConditionalOperator(E)) { | |||
7561 | Fold.keepDiagnostics(); | |||
7562 | return false; | |||
7563 | } | |||
7564 | ||||
7565 | return true; | |||
7566 | } | |||
7567 | ||||
7568 | bool VisitOpaqueValueExpr(const OpaqueValueExpr *E) { | |||
7569 | if (APValue *Value = Info.CurrentCall->getCurrentTemporary(E)) | |||
7570 | return DerivedSuccess(*Value, E); | |||
7571 | ||||
7572 | const Expr *Source = E->getSourceExpr(); | |||
7573 | if (!Source) | |||
7574 | return Error(E); | |||
7575 | if (Source == E) { | |||
7576 | assert(0 && "OpaqueValueExpr recursively refers to itself")(static_cast <bool> (0 && "OpaqueValueExpr recursively refers to itself" ) ? void (0) : __assert_fail ("0 && \"OpaqueValueExpr recursively refers to itself\"" , "clang/lib/AST/ExprConstant.cpp", 7576, __extension__ __PRETTY_FUNCTION__ )); | |||
7577 | return Error(E); | |||
7578 | } | |||
7579 | return StmtVisitorTy::Visit(Source); | |||
7580 | } | |||
7581 | ||||
7582 | bool VisitPseudoObjectExpr(const PseudoObjectExpr *E) { | |||
7583 | for (const Expr *SemE : E->semantics()) { | |||
7584 | if (auto *OVE = dyn_cast<OpaqueValueExpr>(SemE)) { | |||
7585 | // FIXME: We can't handle the case where an OpaqueValueExpr is also the | |||
7586 | // result expression: there could be two different LValues that would | |||
7587 | // refer to the same object in that case, and we can't model that. | |||
7588 | if (SemE == E->getResultExpr()) | |||
7589 | return Error(E); | |||
7590 | ||||
7591 | // Unique OVEs get evaluated if and when we encounter them when | |||
7592 | // emitting the rest of the semantic form, rather than eagerly. | |||
7593 | if (OVE->isUnique()) | |||
7594 | continue; | |||
7595 | ||||
7596 | LValue LV; | |||
7597 | if (!Evaluate(Info.CurrentCall->createTemporary( | |||
7598 | OVE, getStorageType(Info.Ctx, OVE), | |||
7599 | ScopeKind::FullExpression, LV), | |||
7600 | Info, OVE->getSourceExpr())) | |||
7601 | return false; | |||
7602 | } else if (SemE == E->getResultExpr()) { | |||
7603 | if (!StmtVisitorTy::Visit(SemE)) | |||
7604 | return false; | |||
7605 | } else { | |||
7606 | if (!EvaluateIgnoredValue(Info, SemE)) | |||
7607 | return false; | |||
7608 | } | |||
7609 | } | |||
7610 | return true; | |||
7611 | } | |||
7612 | ||||
7613 | bool VisitCallExpr(const CallExpr *E) { | |||
7614 | APValue Result; | |||
7615 | if (!handleCallExpr(E, Result, nullptr)) | |||
7616 | return false; | |||
7617 | return DerivedSuccess(Result, E); | |||
7618 | } | |||
7619 | ||||
7620 | bool handleCallExpr(const CallExpr *E, APValue &Result, | |||
7621 | const LValue *ResultSlot) { | |||
7622 | CallScopeRAII CallScope(Info); | |||
7623 | ||||
7624 | const Expr *Callee = E->getCallee()->IgnoreParens(); | |||
7625 | QualType CalleeType = Callee->getType(); | |||
7626 | ||||
7627 | const FunctionDecl *FD = nullptr; | |||
7628 | LValue *This = nullptr, ThisVal; | |||
7629 | auto Args = llvm::ArrayRef(E->getArgs(), E->getNumArgs()); | |||
7630 | bool HasQualifier = false; | |||
7631 | ||||
7632 | CallRef Call; | |||
7633 | ||||
7634 | // Extract function decl and 'this' pointer from the callee. | |||
7635 | if (CalleeType->isSpecificBuiltinType(BuiltinType::BoundMember)) { | |||
| ||||
7636 | const CXXMethodDecl *Member = nullptr; | |||
7637 | if (const MemberExpr *ME = dyn_cast<MemberExpr>(Callee)) { | |||
7638 | // Explicit bound member calls, such as x.f() or p->g(); | |||
7639 | if (!EvaluateObjectArgument(Info, ME->getBase(), ThisVal)) | |||
7640 | return false; | |||
7641 | Member = dyn_cast<CXXMethodDecl>(ME->getMemberDecl()); | |||
7642 | if (!Member) | |||
7643 | return Error(Callee); | |||
7644 | This = &ThisVal; | |||
7645 | HasQualifier = ME->hasQualifier(); | |||
7646 | } else if (const BinaryOperator *BE = dyn_cast<BinaryOperator>(Callee)) { | |||
7647 | // Indirect bound member calls ('.*' or '->*'). | |||
7648 | const ValueDecl *D = | |||
7649 | HandleMemberPointerAccess(Info, BE, ThisVal, false); | |||
7650 | if (!D) | |||
7651 | return false; | |||
7652 | Member = dyn_cast<CXXMethodDecl>(D); | |||
7653 | if (!Member) | |||
7654 | return Error(Callee); | |||
7655 | This = &ThisVal; | |||
7656 | } else if (const auto *PDE = dyn_cast<CXXPseudoDestructorExpr>(Callee)) { | |||
7657 | if (!Info.getLangOpts().CPlusPlus20) | |||
7658 | Info.CCEDiag(PDE, diag::note_constexpr_pseudo_destructor); | |||
7659 | return EvaluateObjectArgument(Info, PDE->getBase(), ThisVal) && | |||
7660 | HandleDestruction(Info, PDE, ThisVal, PDE->getDestroyedType()); | |||
7661 | } else | |||
7662 | return Error(Callee); | |||
7663 | FD = Member; | |||
7664 | } else if (CalleeType->isFunctionPointerType()) { | |||
7665 | LValue CalleeLV; | |||
7666 | if (!EvaluatePointer(Callee, CalleeLV, Info)) | |||
7667 | return false; | |||
7668 | ||||
7669 | if (!CalleeLV.getLValueOffset().isZero()) | |||
7670 | return Error(Callee); | |||
7671 | if (CalleeLV.isNullPointer()) { | |||
7672 | Info.FFDiag(Callee, diag::note_constexpr_null_callee) | |||
7673 | << const_cast<Expr *>(Callee); | |||
7674 | return false; | |||
7675 | } | |||
7676 | FD = dyn_cast_or_null<FunctionDecl>( | |||
7677 | CalleeLV.getLValueBase().dyn_cast<const ValueDecl *>()); | |||
7678 | if (!FD
| |||
7679 | return Error(Callee); | |||
7680 | // Don't call function pointers which have been cast to some other type. | |||
7681 | // Per DR (no number yet), the caller and callee can differ in noexcept. | |||
7682 | if (!Info.Ctx.hasSameFunctionTypeIgnoringExceptionSpec( | |||
7683 | CalleeType->getPointeeType(), FD->getType())) { | |||
7684 | return Error(E); | |||
7685 | } | |||
7686 | ||||
7687 | // For an (overloaded) assignment expression, evaluate the RHS before the | |||
7688 | // LHS. | |||
7689 | auto *OCE = dyn_cast<CXXOperatorCallExpr>(E); | |||
7690 | if (OCE
| |||
7691 | assert(Args.size() == 2 && "wrong number of arguments in assignment")(static_cast <bool> (Args.size() == 2 && "wrong number of arguments in assignment" ) ? void (0) : __assert_fail ("Args.size() == 2 && \"wrong number of arguments in assignment\"" , "clang/lib/AST/ExprConstant.cpp", 7691, __extension__ __PRETTY_FUNCTION__ )); | |||
7692 | Call = Info.CurrentCall->createCall(FD); | |||
7693 | if (!EvaluateArgs(isa<CXXMethodDecl>(FD) ? Args.slice(1) : Args, Call, | |||
7694 | Info, FD, /*RightToLeft=*/true)) | |||
7695 | return false; | |||
7696 | } | |||
7697 | ||||
7698 | // Overloaded operator calls to member functions are represented as normal | |||
7699 | // calls with '*this' as the first argument. | |||
7700 | const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD); | |||
7701 | if (MD
| |||
7702 | // FIXME: When selecting an implicit conversion for an overloaded | |||
7703 | // operator delete, we sometimes try to evaluate calls to conversion | |||
7704 | // operators without a 'this' parameter! | |||
7705 | if (Args.empty()) | |||
7706 | return Error(E); | |||
7707 | ||||
7708 | if (!EvaluateObjectArgument(Info, Args[0], ThisVal)) | |||
7709 | return false; | |||
7710 | This = &ThisVal; | |||
7711 | ||||
7712 | // If this is syntactically a simple assignment using a trivial | |||
7713 | // assignment operator, start the lifetimes of union members as needed, | |||
7714 | // per C++20 [class.union]5. | |||
7715 | if (Info.getLangOpts().CPlusPlus20 && OCE
| |||
7716 | OCE->getOperator() == OO_Equal && MD->isTrivial() && | |||
7717 | !HandleUnionActiveMemberChange(Info, Args[0], ThisVal)) | |||
7718 | return false; | |||
7719 | ||||
7720 | Args = Args.slice(1); | |||
7721 | } else if (MD && MD->isLambdaStaticInvoker()) { | |||
7722 | // Map the static invoker for the lambda back to the call operator. | |||
7723 | // Conveniently, we don't have to slice out the 'this' argument (as is | |||
7724 | // being done for the non-static case), since a static member function | |||
7725 | // doesn't have an implicit argument passed in. | |||
7726 | const CXXRecordDecl *ClosureClass = MD->getParent(); | |||
7727 | assert((static_cast <bool> (ClosureClass->captures_begin() == ClosureClass->captures_end() && "Number of captures must be zero for conversion to function-ptr" ) ? void (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\"" , "clang/lib/AST/ExprConstant.cpp", 7729, __extension__ __PRETTY_FUNCTION__ )) | |||
7728 | ClosureClass->captures_begin() == ClosureClass->captures_end() &&(static_cast <bool> (ClosureClass->captures_begin() == ClosureClass->captures_end() && "Number of captures must be zero for conversion to function-ptr" ) ? void (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\"" , "clang/lib/AST/ExprConstant.cpp", 7729, __extension__ __PRETTY_FUNCTION__ )) | |||
7729 | "Number of captures must be zero for conversion to function-ptr")(static_cast <bool> (ClosureClass->captures_begin() == ClosureClass->captures_end() && "Number of captures must be zero for conversion to function-ptr" ) ? void (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\"" , "clang/lib/AST/ExprConstant.cpp", 7729, __extension__ __PRETTY_FUNCTION__ )); | |||
7730 | ||||
7731 | const CXXMethodDecl *LambdaCallOp = | |||
7732 | ClosureClass->getLambdaCallOperator(); | |||
7733 | ||||
7734 | // Set 'FD', the function that will be called below, to the call | |||
7735 | // operator. If the closure object represents a generic lambda, find | |||
7736 | // the corresponding specialization of the call operator. | |||
7737 | ||||
7738 | if (ClosureClass->isGenericLambda()) { | |||
7739 | assert(MD->isFunctionTemplateSpecialization() &&(static_cast <bool> (MD->isFunctionTemplateSpecialization () && "A generic lambda's static-invoker function must be a " "template specialization") ? void (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\"" , "clang/lib/AST/ExprConstant.cpp", 7741, __extension__ __PRETTY_FUNCTION__ )) | |||
7740 | "A generic lambda's static-invoker function must be a "(static_cast <bool> (MD->isFunctionTemplateSpecialization () && "A generic lambda's static-invoker function must be a " "template specialization") ? void (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\"" , "clang/lib/AST/ExprConstant.cpp", 7741, __extension__ __PRETTY_FUNCTION__ )) | |||
7741 | "template specialization")(static_cast <bool> (MD->isFunctionTemplateSpecialization () && "A generic lambda's static-invoker function must be a " "template specialization") ? void (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\"" , "clang/lib/AST/ExprConstant.cpp", 7741, __extension__ __PRETTY_FUNCTION__ )); | |||
7742 | const TemplateArgumentList *TAL = MD->getTemplateSpecializationArgs(); | |||
7743 | FunctionTemplateDecl *CallOpTemplate = | |||
7744 | LambdaCallOp->getDescribedFunctionTemplate(); | |||
7745 | void *InsertPos = nullptr; | |||
7746 | FunctionDecl *CorrespondingCallOpSpecialization = | |||
7747 | CallOpTemplate->findSpecialization(TAL->asArray(), InsertPos); | |||
7748 | assert(CorrespondingCallOpSpecialization &&(static_cast <bool> (CorrespondingCallOpSpecialization && "We must always have a function call operator specialization " "that corresponds to our static invoker specialization") ? void (0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\"" , "clang/lib/AST/ExprConstant.cpp", 7750, __extension__ __PRETTY_FUNCTION__ )) | |||
7749 | "We must always have a function call operator specialization "(static_cast <bool> (CorrespondingCallOpSpecialization && "We must always have a function call operator specialization " "that corresponds to our static invoker specialization") ? void (0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\"" , "clang/lib/AST/ExprConstant.cpp", 7750, __extension__ __PRETTY_FUNCTION__ )) | |||
7750 | "that corresponds to our static invoker specialization")(static_cast <bool> (CorrespondingCallOpSpecialization && "We must always have a function call operator specialization " "that corresponds to our static invoker specialization") ? void (0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\"" , "clang/lib/AST/ExprConstant.cpp", 7750, __extension__ __PRETTY_FUNCTION__ )); | |||
7751 | FD = cast<CXXMethodDecl>(CorrespondingCallOpSpecialization); | |||
7752 | } else | |||
7753 | FD = LambdaCallOp; | |||
7754 | } else if (FD->isReplaceableGlobalAllocationFunction()) { | |||
7755 | if (FD->getDeclName().getCXXOverloadedOperator() == OO_New || | |||
7756 | FD->getDeclName().getCXXOverloadedOperator() == OO_Array_New) { | |||
7757 | LValue Ptr; | |||
7758 | if (!HandleOperatorNewCall(Info, E, Ptr)) | |||
7759 | return false; | |||
7760 | Ptr.moveInto(Result); | |||
7761 | return CallScope.destroy(); | |||
7762 | } else { | |||
7763 | return HandleOperatorDeleteCall(Info, E) && CallScope.destroy(); | |||
7764 | } | |||
7765 | } | |||
7766 | } else | |||
7767 | return Error(E); | |||
7768 | ||||
7769 | // Evaluate the arguments now if we've not already done so. | |||
7770 | if (!Call) { | |||
7771 | Call = Info.CurrentCall->createCall(FD); | |||
7772 | if (!EvaluateArgs(Args, Call, Info, FD)) | |||
7773 | return false; | |||
7774 | } | |||
7775 | ||||
7776 | SmallVector<QualType, 4> CovariantAdjustmentPath; | |||
7777 | if (This) { | |||
7778 | auto *NamedMember = dyn_cast<CXXMethodDecl>(FD); | |||
7779 | if (NamedMember && NamedMember->isVirtual() && !HasQualifier) { | |||
7780 | // Perform virtual dispatch, if necessary. | |||
7781 | FD = HandleVirtualDispatch(Info, E, *This, NamedMember, | |||
7782 | CovariantAdjustmentPath); | |||
7783 | if (!FD) | |||
7784 | return false; | |||
7785 | } else { | |||
7786 | // Check that the 'this' pointer points to an object of the right type. | |||
7787 | // FIXME: If this is an assignment operator call, we may need to change | |||
7788 | // the active union member before we check this. | |||
7789 | if (!checkNonVirtualMemberCallThisPointer(Info, E, *This, NamedMember)) | |||
7790 | return false; | |||
7791 | } | |||
7792 | } | |||
7793 | ||||
7794 | // Destructor calls are different enough that they have their own codepath. | |||
7795 | if (auto *DD = dyn_cast<CXXDestructorDecl>(FD)) { | |||
7796 | assert(This && "no 'this' pointer for destructor call")(static_cast <bool> (This && "no 'this' pointer for destructor call" ) ? void (0) : __assert_fail ("This && \"no 'this' pointer for destructor call\"" , "clang/lib/AST/ExprConstant.cpp", 7796, __extension__ __PRETTY_FUNCTION__ )); | |||
7797 | return HandleDestruction(Info, E, *This, | |||
7798 | Info.Ctx.getRecordType(DD->getParent())) && | |||
7799 | CallScope.destroy(); | |||
7800 | } | |||
7801 | ||||
7802 | const FunctionDecl *Definition = nullptr; | |||
7803 | Stmt *Body = FD->getBody(Definition); | |||
7804 | ||||
7805 | if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body) || | |||
7806 | !HandleFunctionCall(E->getExprLoc(), Definition, This, Args, Call, | |||
7807 | Body, Info, Result, ResultSlot)) | |||
7808 | return false; | |||
7809 | ||||
7810 | if (!CovariantAdjustmentPath.empty() && | |||
7811 | !HandleCovariantReturnAdjustment(Info, E, Result, | |||
7812 | CovariantAdjustmentPath)) | |||
7813 | return false; | |||
7814 | ||||
7815 | return CallScope.destroy(); | |||
7816 | } | |||
7817 | ||||
7818 | bool VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) { | |||
7819 | return StmtVisitorTy::Visit(E->getInitializer()); | |||
7820 | } | |||
7821 | bool VisitInitListExpr(const InitListExpr *E) { | |||
7822 | if (E->getNumInits() == 0) | |||
7823 | return DerivedZeroInitialization(E); | |||
7824 | if (E->getNumInits() == 1) | |||
7825 | return StmtVisitorTy::Visit(E->getInit(0)); | |||
7826 | return Error(E); | |||
7827 | } | |||
7828 | bool VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { | |||
7829 | return DerivedZeroInitialization(E); | |||
7830 | } | |||
7831 | bool VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) { | |||
7832 | return DerivedZeroInitialization(E); | |||
7833 | } | |||
7834 | bool VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) { | |||
7835 | return DerivedZeroInitialization(E); | |||
7836 | } | |||
7837 | ||||
7838 | /// A member expression where the object is a prvalue is itself a prvalue. | |||
7839 | bool VisitMemberExpr(const MemberExpr *E) { | |||
7840 | assert(!Info.Ctx.getLangOpts().CPlusPlus11 &&(static_cast <bool> (!Info.Ctx.getLangOpts().CPlusPlus11 && "missing temporary materialization conversion") ? void (0) : __assert_fail ("!Info.Ctx.getLangOpts().CPlusPlus11 && \"missing temporary materialization conversion\"" , "clang/lib/AST/ExprConstant.cpp", 7841, __extension__ __PRETTY_FUNCTION__ )) | |||
7841 | "missing temporary materialization conversion")(static_cast <bool> (!Info.Ctx.getLangOpts().CPlusPlus11 && "missing temporary materialization conversion") ? void (0) : __assert_fail ("!Info.Ctx.getLangOpts().CPlusPlus11 && \"missing temporary materialization conversion\"" , "clang/lib/AST/ExprConstant.cpp", 7841, __extension__ __PRETTY_FUNCTION__ )); | |||
7842 | assert(!E->isArrow() && "missing call to bound member function?")(static_cast <bool> (!E->isArrow() && "missing call to bound member function?" ) ? void (0) : __assert_fail ("!E->isArrow() && \"missing call to bound member function?\"" , "clang/lib/AST/ExprConstant.cpp", 7842, __extension__ __PRETTY_FUNCTION__ )); | |||
7843 | ||||
7844 | APValue Val; | |||
7845 | if (!Evaluate(Val, Info, E->getBase())) | |||
7846 | return false; | |||
7847 | ||||
7848 | QualType BaseTy = E->getBase()->getType(); | |||
7849 | ||||
7850 | const FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl()); | |||
7851 | if (!FD) return Error(E); | |||
7852 | assert(!FD->getType()->isReferenceType() && "prvalue reference?")(static_cast <bool> (!FD->getType()->isReferenceType () && "prvalue reference?") ? void (0) : __assert_fail ("!FD->getType()->isReferenceType() && \"prvalue reference?\"" , "clang/lib/AST/ExprConstant.cpp", 7852, __extension__ __PRETTY_FUNCTION__ )); | |||
7853 | assert(BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() ==(static_cast <bool> (BaseTy->castAs<RecordType> ()->getDecl()->getCanonicalDecl() == FD->getParent() ->getCanonicalDecl() && "record / field mismatch") ? void (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"" , "clang/lib/AST/ExprConstant.cpp", 7854, __extension__ __PRETTY_FUNCTION__ )) | |||
7854 | FD->getParent()->getCanonicalDecl() && "record / field mismatch")(static_cast <bool> (BaseTy->castAs<RecordType> ()->getDecl()->getCanonicalDecl() == FD->getParent() ->getCanonicalDecl() && "record / field mismatch") ? void (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"" , "clang/lib/AST/ExprConstant.cpp", 7854, __extension__ __PRETTY_FUNCTION__ )); | |||
7855 | ||||
7856 | // Note: there is no lvalue base here. But this case should only ever | |||
7857 | // happen in C or in C++98, where we cannot be evaluating a constexpr | |||
7858 | // constructor, which is the only case the base matters. | |||
7859 | CompleteObject Obj(APValue::LValueBase(), &Val, BaseTy); | |||
7860 | SubobjectDesignator Designator(BaseTy); | |||
7861 | Designator.addDeclUnchecked(FD); | |||
7862 | ||||
7863 | APValue Result; | |||
7864 | return extractSubobject(Info, E, Obj, Designator, Result) && | |||
7865 | DerivedSuccess(Result, E); | |||
7866 | } | |||
7867 | ||||
7868 | bool VisitExtVectorElementExpr(const ExtVectorElementExpr *E) { | |||
7869 | APValue Val; | |||
7870 | if (!Evaluate(Val, Info, E->getBase())) | |||
7871 | return false; | |||
7872 | ||||
7873 | if (Val.isVector()) { | |||
7874 | SmallVector<uint32_t, 4> Indices; | |||
7875 | E->getEncodedElementAccess(Indices); | |||
7876 | if (Indices.size() == 1) { | |||
7877 | // Return scalar. | |||
7878 | return DerivedSuccess(Val.getVectorElt(Indices[0]), E); | |||
7879 | } else { | |||
7880 | // Construct new APValue vector. | |||
7881 | SmallVector<APValue, 4> Elts; | |||
7882 | for (unsigned I = 0; I < Indices.size(); ++I) { | |||
7883 | Elts.push_back(Val.getVectorElt(Indices[I])); | |||
7884 | } | |||
7885 | APValue VecResult(Elts.data(), Indices.size()); | |||
7886 | return DerivedSuccess(VecResult, E); | |||
7887 | } | |||
7888 | } | |||
7889 | ||||
7890 | return false; | |||
7891 | } | |||
7892 | ||||
7893 | bool VisitCastExpr(const CastExpr *E) { | |||
7894 | switch (E->getCastKind()) { | |||
7895 | default: | |||
7896 | break; | |||
7897 | ||||
7898 | case CK_AtomicToNonAtomic: { | |||
7899 | APValue AtomicVal; | |||
7900 | // This does not need to be done in place even for class/array types: | |||
7901 | // atomic-to-non-atomic conversion implies copying the object | |||
7902 | // representation. | |||
7903 | if (!Evaluate(AtomicVal, Info, E->getSubExpr())) | |||
7904 | return false; | |||
7905 | return DerivedSuccess(AtomicVal, E); | |||
7906 | } | |||
7907 | ||||
7908 | case CK_NoOp: | |||
7909 | case CK_UserDefinedConversion: | |||
7910 | return StmtVisitorTy::Visit(E->getSubExpr()); | |||
7911 | ||||
7912 | case CK_LValueToRValue: { | |||
7913 | LValue LVal; | |||
7914 | if (!EvaluateLValue(E->getSubExpr(), LVal, Info)) | |||
7915 | return false; | |||
7916 | APValue RVal; | |||
7917 | // Note, we use the subexpression's type in order to retain cv-qualifiers. | |||
7918 | if (!handleLValueToRValueConversion(Info, E, E->getSubExpr()->getType(), | |||
7919 | LVal, RVal)) | |||
7920 | return false; | |||
7921 | return DerivedSuccess(RVal, E); | |||
7922 | } | |||
7923 | case CK_LValueToRValueBitCast: { | |||
7924 | APValue DestValue, SourceValue; | |||
7925 | if (!Evaluate(SourceValue, Info, E->getSubExpr())) | |||
7926 | return false; | |||
7927 | if (!handleLValueToRValueBitCast(Info, DestValue, SourceValue, E)) | |||
7928 | return false; | |||
7929 | return DerivedSuccess(DestValue, E); | |||
7930 | } | |||
7931 | ||||
7932 | case CK_AddressSpaceConversion: { | |||
7933 | APValue Value; | |||
7934 | if (!Evaluate(Value, Info, E->getSubExpr())) | |||
7935 | return false; | |||
7936 | return DerivedSuccess(Value, E); | |||
7937 | } | |||
7938 | } | |||
7939 | ||||
7940 | return Error(E); | |||
7941 | } | |||
7942 | ||||
7943 | bool VisitUnaryPostInc(const UnaryOperator *UO) { | |||
7944 | return VisitUnaryPostIncDec(UO); | |||
7945 | } | |||
7946 | bool VisitUnaryPostDec(const UnaryOperator *UO) { | |||
7947 | return VisitUnaryPostIncDec(UO); | |||
7948 | } | |||
7949 | bool VisitUnaryPostIncDec(const UnaryOperator *UO) { | |||
7950 | if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure()) | |||
7951 | return Error(UO); | |||
7952 | ||||
7953 | LValue LVal; | |||
7954 | if (!EvaluateLValue(UO->getSubExpr(), LVal, Info)) | |||
7955 | return false; | |||
7956 | APValue RVal; | |||
7957 | if (!handleIncDec(this->Info, UO, LVal, UO->getSubExpr()->getType(), | |||
7958 | UO->isIncrementOp(), &RVal)) | |||
7959 | return false; | |||
7960 | return DerivedSuccess(RVal, UO); | |||
7961 | } | |||
7962 | ||||
7963 | bool VisitStmtExpr(const StmtExpr *E) { | |||
7964 | // We will have checked the full-expressions inside the statement expression | |||
7965 | // when they were completed, and don't need to check them again now. | |||
7966 | llvm::SaveAndRestore NotCheckingForUB(Info.CheckingForUndefinedBehavior, | |||
7967 | false); | |||
7968 | ||||
7969 | const CompoundStmt *CS = E->getSubStmt(); | |||
7970 | if (CS->body_empty()) | |||
7971 | return true; | |||
7972 | ||||
7973 | BlockScopeRAII Scope(Info); | |||
7974 | for (CompoundStmt::const_body_iterator BI = CS->body_begin(), | |||
7975 | BE = CS->body_end(); | |||
7976 | /**/; ++BI) { | |||
7977 | if (BI + 1 == BE) { | |||
7978 | const Expr *FinalExpr = dyn_cast<Expr>(*BI); | |||
7979 | if (!FinalExpr) { | |||
7980 | Info.FFDiag((*BI)->getBeginLoc(), | |||
7981 | diag::note_constexpr_stmt_expr_unsupported); | |||
7982 | return false; | |||
7983 | } | |||
7984 | return this->Visit(FinalExpr) && Scope.destroy(); | |||
7985 | } | |||
7986 | ||||
7987 | APValue ReturnValue; | |||
7988 | StmtResult Result = { ReturnValue, nullptr }; | |||
7989 | EvalStmtResult ESR = EvaluateStmt(Result, Info, *BI); | |||
7990 | if (ESR != ESR_Succeeded) { | |||
7991 | // FIXME: If the statement-expression terminated due to 'return', | |||
7992 | // 'break', or 'continue', it would be nice to propagate that to | |||
7993 | // the outer statement evaluation rather than bailing out. | |||
7994 | if (ESR != ESR_Failed) | |||
7995 | Info.FFDiag((*BI)->getBeginLoc(), | |||
7996 | diag::note_constexpr_stmt_expr_unsupported); | |||
7997 | return false; | |||
7998 | } | |||
7999 | } | |||
8000 | ||||
8001 | llvm_unreachable("Return from function from the loop above.")::llvm::llvm_unreachable_internal("Return from function from the loop above." , "clang/lib/AST/ExprConstant.cpp", 8001); | |||
8002 | } | |||
8003 | ||||
8004 | /// Visit a value which is evaluated, but whose value is ignored. | |||
8005 | void VisitIgnoredValue(const Expr *E) { | |||
8006 | EvaluateIgnoredValue(Info, E); | |||
8007 | } | |||
8008 | ||||
8009 | /// Potentially visit a MemberExpr's base expression. | |||
8010 | void VisitIgnoredBaseExpression(const Expr *E) { | |||
8011 | // While MSVC doesn't evaluate the base expression, it does diagnose the | |||
8012 | // presence of side-effecting behavior. | |||
8013 | if (Info.getLangOpts().MSVCCompat && !E->HasSideEffects(Info.Ctx)) | |||
8014 | return; | |||
8015 | VisitIgnoredValue(E); | |||
8016 | } | |||
8017 | }; | |||
8018 | ||||
8019 | } // namespace | |||
8020 | ||||
8021 | //===----------------------------------------------------------------------===// | |||
8022 | // Common base class for lvalue and temporary evaluation. | |||
8023 | //===----------------------------------------------------------------------===// | |||
8024 | namespace { | |||
8025 | template<class Derived> | |||
8026 | class LValueExprEvaluatorBase | |||
8027 | : public ExprEvaluatorBase<Derived> { | |||
8028 | protected: | |||
8029 | LValue &Result; | |||
8030 | bool InvalidBaseOK; | |||
8031 | typedef LValueExprEvaluatorBase LValueExprEvaluatorBaseTy; | |||
8032 | typedef ExprEvaluatorBase<Derived> ExprEvaluatorBaseTy; | |||
8033 | ||||
8034 | bool Success(APValue::LValueBase B) { | |||
8035 | Result.set(B); | |||
8036 | return true; | |||
8037 | } | |||
8038 | ||||
8039 | bool evaluatePointer(const Expr *E, LValue &Result) { | |||
8040 | return EvaluatePointer(E, Result, this->Info, InvalidBaseOK); | |||
8041 | } | |||
8042 | ||||
8043 | public: | |||
8044 | LValueExprEvaluatorBase(EvalInfo &Info, LValue &Result, bool InvalidBaseOK) | |||
8045 | : ExprEvaluatorBaseTy(Info), Result(Result), | |||
8046 | InvalidBaseOK(InvalidBaseOK) {} | |||
8047 | ||||
8048 | bool Success(const APValue &V, const Expr *E) { | |||
8049 | Result.setFrom(this->Info.Ctx, V); | |||
8050 | return true; | |||
8051 | } | |||
8052 | ||||
8053 | bool VisitMemberExpr(const MemberExpr *E) { | |||
8054 | // Handle non-static data members. | |||
8055 | QualType BaseTy; | |||
8056 | bool EvalOK; | |||
8057 | if (E->isArrow()) { | |||
8058 | EvalOK = evaluatePointer(E->getBase(), Result); | |||
8059 | BaseTy = E->getBase()->getType()->castAs<PointerType>()->getPointeeType(); | |||
8060 | } else if (E->getBase()->isPRValue()) { | |||
8061 | assert(E->getBase()->getType()->isRecordType())(static_cast <bool> (E->getBase()->getType()-> isRecordType()) ? void (0) : __assert_fail ("E->getBase()->getType()->isRecordType()" , "clang/lib/AST/ExprConstant.cpp", 8061, __extension__ __PRETTY_FUNCTION__ )); | |||
8062 | EvalOK = EvaluateTemporary(E->getBase(), Result, this->Info); | |||
8063 | BaseTy = E->getBase()->getType(); | |||
8064 | } else { | |||
8065 | EvalOK = this->Visit(E->getBase()); | |||
8066 | BaseTy = E->getBase()->getType(); | |||
8067 | } | |||
8068 | if (!EvalOK) { | |||
8069 | if (!InvalidBaseOK) | |||
8070 | return false; | |||
8071 | Result.setInvalid(E); | |||
8072 | return true; | |||
8073 | } | |||
8074 | ||||
8075 | const ValueDecl *MD = E->getMemberDecl(); | |||
8076 | if (const FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl())) { | |||
8077 | assert(BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() ==(static_cast <bool> (BaseTy->castAs<RecordType> ()->getDecl()->getCanonicalDecl() == FD->getParent() ->getCanonicalDecl() && "record / field mismatch") ? void (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"" , "clang/lib/AST/ExprConstant.cpp", 8078, __extension__ __PRETTY_FUNCTION__ )) | |||
8078 | FD->getParent()->getCanonicalDecl() && "record / field mismatch")(static_cast <bool> (BaseTy->castAs<RecordType> ()->getDecl()->getCanonicalDecl() == FD->getParent() ->getCanonicalDecl() && "record / field mismatch") ? void (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"" , "clang/lib/AST/ExprConstant.cpp", 8078, __extension__ __PRETTY_FUNCTION__ )); | |||
8079 | (void)BaseTy; | |||
8080 | if (!HandleLValueMember(this->Info, E, Result, FD)) | |||
8081 | return false; | |||
8082 | } else if (const IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(MD)) { | |||
8083 | if (!HandleLValueIndirectMember(this->Info, E, Result, IFD)) | |||
8084 | return false; | |||
8085 | } else | |||
8086 | return this->Error(E); | |||
8087 | ||||
8088 | if (MD->getType()->isReferenceType()) { | |||
8089 | APValue RefValue; | |||
8090 | if (!handleLValueToRValueConversion(this->Info, E, MD->getType(), Result, | |||
8091 | RefValue)) | |||
8092 | return false; | |||
8093 | return Success(RefValue, E); | |||
8094 | } | |||
8095 | return true; | |||
8096 | } | |||
8097 | ||||
8098 | bool VisitBinaryOperator(const BinaryOperator *E) { | |||
8099 | switch (E->getOpcode()) { | |||
8100 | default: | |||
8101 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
8102 | ||||
8103 | case BO_PtrMemD: | |||
8104 | case BO_PtrMemI: | |||
8105 | return HandleMemberPointerAccess(this->Info, E, Result); | |||
8106 | } | |||
8107 | } | |||
8108 | ||||
8109 | bool VisitCastExpr(const CastExpr *E) { | |||
8110 | switch (E->getCastKind()) { | |||
8111 | default: | |||
8112 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
8113 | ||||
8114 | case CK_DerivedToBase: | |||
8115 | case CK_UncheckedDerivedToBase: | |||
8116 | if (!this->Visit(E->getSubExpr())) | |||
8117 | return false; | |||
8118 | ||||
8119 | // Now figure out the necessary offset to add to the base LV to get from | |||
8120 | // the derived class to the base class. | |||
8121 | return HandleLValueBasePath(this->Info, E, E->getSubExpr()->getType(), | |||
8122 | Result); | |||
8123 | } | |||
8124 | } | |||
8125 | }; | |||
8126 | } | |||
8127 | ||||
8128 | //===----------------------------------------------------------------------===// | |||
8129 | // LValue Evaluation | |||
8130 | // | |||
8131 | // This is used for evaluating lvalues (in C and C++), xvalues (in C++11), | |||
8132 | // function designators (in C), decl references to void objects (in C), and | |||
8133 | // temporaries (if building with -Wno-address-of-temporary). | |||
8134 | // | |||
8135 | // LValue evaluation produces values comprising a base expression of one of the | |||
8136 | // following types: | |||
8137 | // - Declarations | |||
8138 | // * VarDecl | |||
8139 | // * FunctionDecl | |||
8140 | // - Literals | |||
8141 | // * CompoundLiteralExpr in C (and in global scope in C++) | |||
8142 | // * StringLiteral | |||
8143 | // * PredefinedExpr | |||
8144 | // * ObjCStringLiteralExpr | |||
8145 | // * ObjCEncodeExpr | |||
8146 | // * AddrLabelExpr | |||
8147 | // * BlockExpr | |||
8148 | // * CallExpr for a MakeStringConstant builtin | |||
8149 | // - typeid(T) expressions, as TypeInfoLValues | |||
8150 | // - Locals and temporaries | |||
8151 | // * MaterializeTemporaryExpr | |||
8152 | // * Any Expr, with a CallIndex indicating the function in which the temporary | |||
8153 | // was evaluated, for cases where the MaterializeTemporaryExpr is missing | |||
8154 | // from the AST (FIXME). | |||
8155 | // * A MaterializeTemporaryExpr that has static storage duration, with no | |||
8156 | // CallIndex, for a lifetime-extended temporary. | |||
8157 | // * The ConstantExpr that is currently being evaluated during evaluation of an | |||
8158 | // immediate invocation. | |||
8159 | // plus an offset in bytes. | |||
8160 | //===----------------------------------------------------------------------===// | |||
8161 | namespace { | |||
8162 | class LValueExprEvaluator | |||
8163 | : public LValueExprEvaluatorBase<LValueExprEvaluator> { | |||
8164 | public: | |||
8165 | LValueExprEvaluator(EvalInfo &Info, LValue &Result, bool InvalidBaseOK) : | |||
8166 | LValueExprEvaluatorBaseTy(Info, Result, InvalidBaseOK) {} | |||
8167 | ||||
8168 | bool VisitVarDecl(const Expr *E, const VarDecl *VD); | |||
8169 | bool VisitUnaryPreIncDec(const UnaryOperator *UO); | |||
8170 | ||||
8171 | bool VisitCallExpr(const CallExpr *E); | |||
8172 | bool VisitDeclRefExpr(const DeclRefExpr *E); | |||
8173 | bool VisitPredefinedExpr(const PredefinedExpr *E) { return Success(E); } | |||
8174 | bool VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E); | |||
8175 | bool VisitCompoundLiteralExpr(const CompoundLiteralExpr *E); | |||
8176 | bool VisitMemberExpr(const MemberExpr *E); | |||
8177 | bool VisitStringLiteral(const StringLiteral *E) { return Success(E); } | |||
8178 | bool VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { return Success(E); } | |||
8179 | bool VisitCXXTypeidExpr(const CXXTypeidExpr *E); | |||
8180 | bool VisitCXXUuidofExpr(const CXXUuidofExpr *E); | |||
8181 | bool VisitArraySubscriptExpr(const ArraySubscriptExpr *E); | |||
8182 | bool VisitUnaryDeref(const UnaryOperator *E); | |||
8183 | bool VisitUnaryReal(const UnaryOperator *E); | |||
8184 | bool VisitUnaryImag(const UnaryOperator *E); | |||
8185 | bool VisitUnaryPreInc(const UnaryOperator *UO) { | |||
8186 | return VisitUnaryPreIncDec(UO); | |||
8187 | } | |||
8188 | bool VisitUnaryPreDec(const UnaryOperator *UO) { | |||
8189 | return VisitUnaryPreIncDec(UO); | |||
8190 | } | |||
8191 | bool VisitBinAssign(const BinaryOperator *BO); | |||
8192 | bool VisitCompoundAssignOperator(const CompoundAssignOperator *CAO); | |||
8193 | ||||
8194 | bool VisitCastExpr(const CastExpr *E) { | |||
8195 | switch (E->getCastKind()) { | |||
8196 | default: | |||
8197 | return LValueExprEvaluatorBaseTy::VisitCastExpr(E); | |||
8198 | ||||
8199 | case CK_LValueBitCast: | |||
8200 | this->CCEDiag(E, diag::note_constexpr_invalid_cast) | |||
8201 | << 2 << Info.Ctx.getLangOpts().CPlusPlus; | |||
8202 | if (!Visit(E->getSubExpr())) | |||
8203 | return false; | |||
8204 | Result.Designator.setInvalid(); | |||
8205 | return true; | |||
8206 | ||||
8207 | case CK_BaseToDerived: | |||
8208 | if (!Visit(E->getSubExpr())) | |||
8209 | return false; | |||
8210 | return HandleBaseToDerivedCast(Info, E, Result); | |||
8211 | ||||
8212 | case CK_Dynamic: | |||
8213 | if (!Visit(E->getSubExpr())) | |||
8214 | return false; | |||
8215 | return HandleDynamicCast(Info, cast<ExplicitCastExpr>(E), Result); | |||
8216 | } | |||
8217 | } | |||
8218 | }; | |||
8219 | } // end anonymous namespace | |||
8220 | ||||
8221 | /// Evaluate an expression as an lvalue. This can be legitimately called on | |||
8222 | /// expressions which are not glvalues, in three cases: | |||
8223 | /// * function designators in C, and | |||
8224 | /// * "extern void" objects | |||
8225 | /// * @selector() expressions in Objective-C | |||
8226 | static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info, | |||
8227 | bool InvalidBaseOK) { | |||
8228 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 8228, __extension__ __PRETTY_FUNCTION__)); | |||
8229 | assert(E->isGLValue() || E->getType()->isFunctionType() ||(static_cast <bool> (E->isGLValue() || E->getType ()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E->IgnoreParens())) ? void (0 ) : __assert_fail ("E->isGLValue() || E->getType()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E->IgnoreParens())" , "clang/lib/AST/ExprConstant.cpp", 8230, __extension__ __PRETTY_FUNCTION__ )) | |||
8230 | E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E->IgnoreParens()))(static_cast <bool> (E->isGLValue() || E->getType ()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E->IgnoreParens())) ? void (0 ) : __assert_fail ("E->isGLValue() || E->getType()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E->IgnoreParens())" , "clang/lib/AST/ExprConstant.cpp", 8230, __extension__ __PRETTY_FUNCTION__ )); | |||
8231 | return LValueExprEvaluator(Info, Result, InvalidBaseOK).Visit(E); | |||
8232 | } | |||
8233 | ||||
8234 | bool LValueExprEvaluator::VisitDeclRefExpr(const DeclRefExpr *E) { | |||
8235 | const NamedDecl *D = E->getDecl(); | |||
8236 | if (isa<FunctionDecl, MSGuidDecl, TemplateParamObjectDecl, | |||
8237 | UnnamedGlobalConstantDecl>(D)) | |||
8238 | return Success(cast<ValueDecl>(D)); | |||
8239 | if (const VarDecl *VD = dyn_cast<VarDecl>(D)) | |||
8240 | return VisitVarDecl(E, VD); | |||
8241 | if (const BindingDecl *BD = dyn_cast<BindingDecl>(D)) | |||
8242 | return Visit(BD->getBinding()); | |||
8243 | return Error(E); | |||
8244 | } | |||
8245 | ||||
8246 | ||||
8247 | bool LValueExprEvaluator::VisitVarDecl(const Expr *E, const VarDecl *VD) { | |||
8248 | ||||
8249 | // If we are within a lambda's call operator, check whether the 'VD' referred | |||
8250 | // to within 'E' actually represents a lambda-capture that maps to a | |||
8251 | // data-member/field within the closure object, and if so, evaluate to the | |||
8252 | // field or what the field refers to. | |||
8253 | if (Info.CurrentCall && isLambdaCallOperator(Info.CurrentCall->Callee) && | |||
8254 | isa<DeclRefExpr>(E) && | |||
8255 | cast<DeclRefExpr>(E)->refersToEnclosingVariableOrCapture()) { | |||
8256 | // We don't always have a complete capture-map when checking or inferring if | |||
8257 | // the function call operator meets the requirements of a constexpr function | |||
8258 | // - but we don't need to evaluate the captures to determine constexprness | |||
8259 | // (dcl.constexpr C++17). | |||
8260 | if (Info.checkingPotentialConstantExpression()) | |||
8261 | return false; | |||
8262 | ||||
8263 | if (auto *FD = Info.CurrentCall->LambdaCaptureFields.lookup(VD)) { | |||
8264 | // Start with 'Result' referring to the complete closure object... | |||
8265 | Result = *Info.CurrentCall->This; | |||
8266 | // ... then update it to refer to the field of the closure object | |||
8267 | // that represents the capture. | |||
8268 | if (!HandleLValueMember(Info, E, Result, FD)) | |||
8269 | return false; | |||
8270 | // And if the field is of reference type, update 'Result' to refer to what | |||
8271 | // the field refers to. | |||
8272 | if (FD->getType()->isReferenceType()) { | |||
8273 | APValue RVal; | |||
8274 | if (!handleLValueToRValueConversion(Info, E, FD->getType(), Result, | |||
8275 | RVal)) | |||
8276 | return false; | |||
8277 | Result.setFrom(Info.Ctx, RVal); | |||
8278 | } | |||
8279 | return true; | |||
8280 | } | |||
8281 | } | |||
8282 | ||||
8283 | CallStackFrame *Frame = nullptr; | |||
8284 | unsigned Version = 0; | |||
8285 | if (VD->hasLocalStorage()) { | |||
8286 | // Only if a local variable was declared in the function currently being | |||
8287 | // evaluated, do we expect to be able to find its value in the current | |||
8288 | // frame. (Otherwise it was likely declared in an enclosing context and | |||
8289 | // could either have a valid evaluatable value (for e.g. a constexpr | |||
8290 | // variable) or be ill-formed (and trigger an appropriate evaluation | |||
8291 | // diagnostic)). | |||
8292 | CallStackFrame *CurrFrame = Info.CurrentCall; | |||
8293 | if (CurrFrame->Callee && CurrFrame->Callee->Equals(VD->getDeclContext())) { | |||
8294 | // Function parameters are stored in some caller's frame. (Usually the | |||
8295 | // immediate caller, but for an inherited constructor they may be more | |||
8296 | // distant.) | |||
8297 | if (auto *PVD = dyn_cast<ParmVarDecl>(VD)) { | |||
8298 | if (CurrFrame->Arguments) { | |||
8299 | VD = CurrFrame->Arguments.getOrigParam(PVD); | |||
8300 | Frame = | |||
8301 | Info.getCallFrameAndDepth(CurrFrame->Arguments.CallIndex).first; | |||
8302 | Version = CurrFrame->Arguments.Version; | |||
8303 | } | |||
8304 | } else { | |||
8305 | Frame = CurrFrame; | |||
8306 | Version = CurrFrame->getCurrentTemporaryVersion(VD); | |||
8307 | } | |||
8308 | } | |||
8309 | } | |||
8310 | ||||
8311 | if (!VD->getType()->isReferenceType()) { | |||
8312 | if (Frame) { | |||
8313 | Result.set({VD, Frame->Index, Version}); | |||
8314 | return true; | |||
8315 | } | |||
8316 | return Success(VD); | |||
8317 | } | |||
8318 | ||||
8319 | if (!Info.getLangOpts().CPlusPlus11) { | |||
8320 | Info.CCEDiag(E, diag::note_constexpr_ltor_non_integral, 1) | |||
8321 | << VD << VD->getType(); | |||
8322 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
8323 | } | |||
8324 | ||||
8325 | APValue *V; | |||
8326 | if (!evaluateVarDeclInit(Info, E, VD, Frame, Version, V)) | |||
8327 | return false; | |||
8328 | if (!V->hasValue()) { | |||
8329 | // FIXME: Is it possible for V to be indeterminate here? If so, we should | |||
8330 | // adjust the diagnostic to say that. | |||
8331 | if (!Info.checkingPotentialConstantExpression()) | |||
8332 | Info.FFDiag(E, diag::note_constexpr_use_uninit_reference); | |||
8333 | return false; | |||
8334 | } | |||
8335 | return Success(*V, E); | |||
8336 | } | |||
8337 | ||||
8338 | bool LValueExprEvaluator::VisitCallExpr(const CallExpr *E) { | |||
8339 | if (!IsConstantEvaluatedBuiltinCall(E)) | |||
8340 | return ExprEvaluatorBaseTy::VisitCallExpr(E); | |||
8341 | ||||
8342 | switch (E->getBuiltinCallee()) { | |||
8343 | default: | |||
8344 | return false; | |||
8345 | case Builtin::BIas_const: | |||
8346 | case Builtin::BIforward: | |||
8347 | case Builtin::BIforward_like: | |||
8348 | case Builtin::BImove: | |||
8349 | case Builtin::BImove_if_noexcept: | |||
8350 | if (cast<FunctionDecl>(E->getCalleeDecl())->isConstexpr()) | |||
8351 | return Visit(E->getArg(0)); | |||
8352 | break; | |||
8353 | } | |||
8354 | ||||
8355 | return ExprEvaluatorBaseTy::VisitCallExpr(E); | |||
8356 | } | |||
8357 | ||||
8358 | bool LValueExprEvaluator::VisitMaterializeTemporaryExpr( | |||
8359 | const MaterializeTemporaryExpr *E) { | |||
8360 | // Walk through the expression to find the materialized temporary itself. | |||
8361 | SmallVector<const Expr *, 2> CommaLHSs; | |||
8362 | SmallVector<SubobjectAdjustment, 2> Adjustments; | |||
8363 | const Expr *Inner = | |||
8364 | E->getSubExpr()->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); | |||
8365 | ||||
8366 | // If we passed any comma operators, evaluate their LHSs. | |||
8367 | for (unsigned I = 0, N = CommaLHSs.size(); I != N; ++I) | |||
8368 | if (!EvaluateIgnoredValue(Info, CommaLHSs[I])) | |||
8369 | return false; | |||
8370 | ||||
8371 | // A materialized temporary with static storage duration can appear within the | |||
8372 | // result of a constant expression evaluation, so we need to preserve its | |||
8373 | // value for use outside this evaluation. | |||
8374 | APValue *Value; | |||
8375 | if (E->getStorageDuration() == SD_Static) { | |||
8376 | // FIXME: What about SD_Thread? | |||
8377 | Value = E->getOrCreateValue(true); | |||
8378 | *Value = APValue(); | |||
8379 | Result.set(E); | |||
8380 | } else { | |||
8381 | Value = &Info.CurrentCall->createTemporary( | |||
8382 | E, E->getType(), | |||
8383 | E->getStorageDuration() == SD_FullExpression ? ScopeKind::FullExpression | |||
8384 | : ScopeKind::Block, | |||
8385 | Result); | |||
8386 | } | |||
8387 | ||||
8388 | QualType Type = Inner->getType(); | |||
8389 | ||||
8390 | // Materialize the temporary itself. | |||
8391 | if (!EvaluateInPlace(*Value, Info, Result, Inner)) { | |||
8392 | *Value = APValue(); | |||
8393 | return false; | |||
8394 | } | |||
8395 | ||||
8396 | // Adjust our lvalue to refer to the desired subobject. | |||
8397 | for (unsigned I = Adjustments.size(); I != 0; /**/) { | |||
8398 | --I; | |||
8399 | switch (Adjustments[I].Kind) { | |||
8400 | case SubobjectAdjustment::DerivedToBaseAdjustment: | |||
8401 | if (!HandleLValueBasePath(Info, Adjustments[I].DerivedToBase.BasePath, | |||
8402 | Type, Result)) | |||
8403 | return false; | |||
8404 | Type = Adjustments[I].DerivedToBase.BasePath->getType(); | |||
8405 | break; | |||
8406 | ||||
8407 | case SubobjectAdjustment::FieldAdjustment: | |||
8408 | if (!HandleLValueMember(Info, E, Result, Adjustments[I].Field)) | |||
8409 | return false; | |||
8410 | Type = Adjustments[I].Field->getType(); | |||
8411 | break; | |||
8412 | ||||
8413 | case SubobjectAdjustment::MemberPointerAdjustment: | |||
8414 | if (!HandleMemberPointerAccess(this->Info, Type, Result, | |||
8415 | Adjustments[I].Ptr.RHS)) | |||
8416 | return false; | |||
8417 | Type = Adjustments[I].Ptr.MPT->getPointeeType(); | |||
8418 | break; | |||
8419 | } | |||
8420 | } | |||
8421 | ||||
8422 | return true; | |||
8423 | } | |||
8424 | ||||
8425 | bool | |||
8426 | LValueExprEvaluator::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) { | |||
8427 | assert((!Info.getLangOpts().CPlusPlus || E->isFileScope()) &&(static_cast <bool> ((!Info.getLangOpts().CPlusPlus || E ->isFileScope()) && "lvalue compound literal in c++?" ) ? void (0) : __assert_fail ("(!Info.getLangOpts().CPlusPlus || E->isFileScope()) && \"lvalue compound literal in c++?\"" , "clang/lib/AST/ExprConstant.cpp", 8428, __extension__ __PRETTY_FUNCTION__ )) | |||
8428 | "lvalue compound literal in c++?")(static_cast <bool> ((!Info.getLangOpts().CPlusPlus || E ->isFileScope()) && "lvalue compound literal in c++?" ) ? void (0) : __assert_fail ("(!Info.getLangOpts().CPlusPlus || E->isFileScope()) && \"lvalue compound literal in c++?\"" , "clang/lib/AST/ExprConstant.cpp", 8428, __extension__ __PRETTY_FUNCTION__ )); | |||
8429 | // Defer visiting the literal until the lvalue-to-rvalue conversion. We can | |||
8430 | // only see this when folding in C, so there's no standard to follow here. | |||
8431 | return Success(E); | |||
8432 | } | |||
8433 | ||||
8434 | bool LValueExprEvaluator::VisitCXXTypeidExpr(const CXXTypeidExpr *E) { | |||
8435 | TypeInfoLValue TypeInfo; | |||
8436 | ||||
8437 | if (!E->isPotentiallyEvaluated()) { | |||
8438 | if (E->isTypeOperand()) | |||
8439 | TypeInfo = TypeInfoLValue(E->getTypeOperand(Info.Ctx).getTypePtr()); | |||
8440 | else | |||
8441 | TypeInfo = TypeInfoLValue(E->getExprOperand()->getType().getTypePtr()); | |||
8442 | } else { | |||
8443 | if (!Info.Ctx.getLangOpts().CPlusPlus20) { | |||
8444 | Info.CCEDiag(E, diag::note_constexpr_typeid_polymorphic) | |||
8445 | << E->getExprOperand()->getType() | |||
8446 | << E->getExprOperand()->getSourceRange(); | |||
8447 | } | |||
8448 | ||||
8449 | if (!Visit(E->getExprOperand())) | |||
8450 | return false; | |||
8451 | ||||
8452 | std::optional<DynamicType> DynType = | |||
8453 | ComputeDynamicType(Info, E, Result, AK_TypeId); | |||
8454 | if (!DynType) | |||
8455 | return false; | |||
8456 | ||||
8457 | TypeInfo = | |||
8458 | TypeInfoLValue(Info.Ctx.getRecordType(DynType->Type).getTypePtr()); | |||
8459 | } | |||
8460 | ||||
8461 | return Success(APValue::LValueBase::getTypeInfo(TypeInfo, E->getType())); | |||
8462 | } | |||
8463 | ||||
8464 | bool LValueExprEvaluator::VisitCXXUuidofExpr(const CXXUuidofExpr *E) { | |||
8465 | return Success(E->getGuidDecl()); | |||
8466 | } | |||
8467 | ||||
8468 | bool LValueExprEvaluator::VisitMemberExpr(const MemberExpr *E) { | |||
8469 | // Handle static data members. | |||
8470 | if (const VarDecl *VD = dyn_cast<VarDecl>(E->getMemberDecl())) { | |||
8471 | VisitIgnoredBaseExpression(E->getBase()); | |||
8472 | return VisitVarDecl(E, VD); | |||
8473 | } | |||
8474 | ||||
8475 | // Handle static member functions. | |||
8476 | if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl())) { | |||
8477 | if (MD->isStatic()) { | |||
8478 | VisitIgnoredBaseExpression(E->getBase()); | |||
8479 | return Success(MD); | |||
8480 | } | |||
8481 | } | |||
8482 | ||||
8483 | // Handle non-static data members. | |||
8484 | return LValueExprEvaluatorBaseTy::VisitMemberExpr(E); | |||
8485 | } | |||
8486 | ||||
8487 | bool LValueExprEvaluator::VisitArraySubscriptExpr(const ArraySubscriptExpr *E) { | |||
8488 | // FIXME: Deal with vectors as array subscript bases. | |||
8489 | if (E->getBase()->getType()->isVectorType() || | |||
8490 | E->getBase()->getType()->isVLSTBuiltinType()) | |||
8491 | return Error(E); | |||
8492 | ||||
8493 | APSInt Index; | |||
8494 | bool Success = true; | |||
8495 | ||||
8496 | // C++17's rules require us to evaluate the LHS first, regardless of which | |||
8497 | // side is the base. | |||
8498 | for (const Expr *SubExpr : {E->getLHS(), E->getRHS()}) { | |||
8499 | if (SubExpr == E->getBase() ? !evaluatePointer(SubExpr, Result) | |||
8500 | : !EvaluateInteger(SubExpr, Index, Info)) { | |||
8501 | if (!Info.noteFailure()) | |||
8502 | return false; | |||
8503 | Success = false; | |||
8504 | } | |||
8505 | } | |||
8506 | ||||
8507 | return Success && | |||
8508 | HandleLValueArrayAdjustment(Info, E, Result, E->getType(), Index); | |||
8509 | } | |||
8510 | ||||
8511 | bool LValueExprEvaluator::VisitUnaryDeref(const UnaryOperator *E) { | |||
8512 | return evaluatePointer(E->getSubExpr(), Result); | |||
8513 | } | |||
8514 | ||||
8515 | bool LValueExprEvaluator::VisitUnaryReal(const UnaryOperator *E) { | |||
8516 | if (!Visit(E->getSubExpr())) | |||
8517 | return false; | |||
8518 | // __real is a no-op on scalar lvalues. | |||
8519 | if (E->getSubExpr()->getType()->isAnyComplexType()) | |||
8520 | HandleLValueComplexElement(Info, E, Result, E->getType(), false); | |||
8521 | return true; | |||
8522 | } | |||
8523 | ||||
8524 | bool LValueExprEvaluator::VisitUnaryImag(const UnaryOperator *E) { | |||
8525 | assert(E->getSubExpr()->getType()->isAnyComplexType() &&(static_cast <bool> (E->getSubExpr()->getType()-> isAnyComplexType() && "lvalue __imag__ on scalar?") ? void (0) : __assert_fail ("E->getSubExpr()->getType()->isAnyComplexType() && \"lvalue __imag__ on scalar?\"" , "clang/lib/AST/ExprConstant.cpp", 8526, __extension__ __PRETTY_FUNCTION__ )) | |||
8526 | "lvalue __imag__ on scalar?")(static_cast <bool> (E->getSubExpr()->getType()-> isAnyComplexType() && "lvalue __imag__ on scalar?") ? void (0) : __assert_fail ("E->getSubExpr()->getType()->isAnyComplexType() && \"lvalue __imag__ on scalar?\"" , "clang/lib/AST/ExprConstant.cpp", 8526, __extension__ __PRETTY_FUNCTION__ )); | |||
8527 | if (!Visit(E->getSubExpr())) | |||
8528 | return false; | |||
8529 | HandleLValueComplexElement(Info, E, Result, E->getType(), true); | |||
8530 | return true; | |||
8531 | } | |||
8532 | ||||
8533 | bool LValueExprEvaluator::VisitUnaryPreIncDec(const UnaryOperator *UO) { | |||
8534 | if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure()) | |||
8535 | return Error(UO); | |||
8536 | ||||
8537 | if (!this->Visit(UO->getSubExpr())) | |||
8538 | return false; | |||
8539 | ||||
8540 | return handleIncDec( | |||
8541 | this->Info, UO, Result, UO->getSubExpr()->getType(), | |||
8542 | UO->isIncrementOp(), nullptr); | |||
8543 | } | |||
8544 | ||||
8545 | bool LValueExprEvaluator::VisitCompoundAssignOperator( | |||
8546 | const CompoundAssignOperator *CAO) { | |||
8547 | if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure()) | |||
8548 | return Error(CAO); | |||
8549 | ||||
8550 | bool Success = true; | |||
8551 | ||||
8552 | // C++17 onwards require that we evaluate the RHS first. | |||
8553 | APValue RHS; | |||
8554 | if (!Evaluate(RHS, this->Info, CAO->getRHS())) { | |||
8555 | if (!Info.noteFailure()) | |||
8556 | return false; | |||
8557 | Success = false; | |||
8558 | } | |||
8559 | ||||
8560 | // The overall lvalue result is the result of evaluating the LHS. | |||
8561 | if (!this->Visit(CAO->getLHS()) || !Success) | |||
8562 | return false; | |||
8563 | ||||
8564 | return handleCompoundAssignment( | |||
8565 | this->Info, CAO, | |||
8566 | Result, CAO->getLHS()->getType(), CAO->getComputationLHSType(), | |||
8567 | CAO->getOpForCompoundAssignment(CAO->getOpcode()), RHS); | |||
8568 | } | |||
8569 | ||||
8570 | bool LValueExprEvaluator::VisitBinAssign(const BinaryOperator *E) { | |||
8571 | if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure()) | |||
8572 | return Error(E); | |||
8573 | ||||
8574 | bool Success = true; | |||
8575 | ||||
8576 | // C++17 onwards require that we evaluate the RHS first. | |||
8577 | APValue NewVal; | |||
8578 | if (!Evaluate(NewVal, this->Info, E->getRHS())) { | |||
8579 | if (!Info.noteFailure()) | |||
8580 | return false; | |||
8581 | Success = false; | |||
8582 | } | |||
8583 | ||||
8584 | if (!this->Visit(E->getLHS()) || !Success) | |||
8585 | return false; | |||
8586 | ||||
8587 | if (Info.getLangOpts().CPlusPlus20 && | |||
8588 | !HandleUnionActiveMemberChange(Info, E->getLHS(), Result)) | |||
8589 | return false; | |||
8590 | ||||
8591 | return handleAssignment(this->Info, E, Result, E->getLHS()->getType(), | |||
8592 | NewVal); | |||
8593 | } | |||
8594 | ||||
8595 | //===----------------------------------------------------------------------===// | |||
8596 | // Pointer Evaluation | |||
8597 | //===----------------------------------------------------------------------===// | |||
8598 | ||||
8599 | /// Attempts to compute the number of bytes available at the pointer | |||
8600 | /// returned by a function with the alloc_size attribute. Returns true if we | |||
8601 | /// were successful. Places an unsigned number into `Result`. | |||
8602 | /// | |||
8603 | /// This expects the given CallExpr to be a call to a function with an | |||
8604 | /// alloc_size attribute. | |||
8605 | static bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx, | |||
8606 | const CallExpr *Call, | |||
8607 | llvm::APInt &Result) { | |||
8608 | const AllocSizeAttr *AllocSize = getAllocSizeAttr(Call); | |||
8609 | ||||
8610 | assert(AllocSize && AllocSize->getElemSizeParam().isValid())(static_cast <bool> (AllocSize && AllocSize-> getElemSizeParam().isValid()) ? void (0) : __assert_fail ("AllocSize && AllocSize->getElemSizeParam().isValid()" , "clang/lib/AST/ExprConstant.cpp", 8610, __extension__ __PRETTY_FUNCTION__ )); | |||
8611 | unsigned SizeArgNo = AllocSize->getElemSizeParam().getASTIndex(); | |||
8612 | unsigned BitsInSizeT = Ctx.getTypeSize(Ctx.getSizeType()); | |||
8613 | if (Call->getNumArgs() <= SizeArgNo) | |||
8614 | return false; | |||
8615 | ||||
8616 | auto EvaluateAsSizeT = [&](const Expr *E, APSInt &Into) { | |||
8617 | Expr::EvalResult ExprResult; | |||
8618 | if (!E->EvaluateAsInt(ExprResult, Ctx, Expr::SE_AllowSideEffects)) | |||
8619 | return false; | |||
8620 | Into = ExprResult.Val.getInt(); | |||
8621 | if (Into.isNegative() || !Into.isIntN(BitsInSizeT)) | |||
8622 | return false; | |||
8623 | Into = Into.zext(BitsInSizeT); | |||
8624 | return true; | |||
8625 | }; | |||
8626 | ||||
8627 | APSInt SizeOfElem; | |||
8628 | if (!EvaluateAsSizeT(Call->getArg(SizeArgNo), SizeOfElem)) | |||
8629 | return false; | |||
8630 | ||||
8631 | if (!AllocSize->getNumElemsParam().isValid()) { | |||
8632 | Result = std::move(SizeOfElem); | |||
8633 | return true; | |||
8634 | } | |||
8635 | ||||
8636 | APSInt NumberOfElems; | |||
8637 | unsigned NumArgNo = AllocSize->getNumElemsParam().getASTIndex(); | |||
8638 | if (!EvaluateAsSizeT(Call->getArg(NumArgNo), NumberOfElems)) | |||
8639 | return false; | |||
8640 | ||||
8641 | bool Overflow; | |||
8642 | llvm::APInt BytesAvailable = SizeOfElem.umul_ov(NumberOfElems, Overflow); | |||
8643 | if (Overflow) | |||
8644 | return false; | |||
8645 | ||||
8646 | Result = std::move(BytesAvailable); | |||
8647 | return true; | |||
8648 | } | |||
8649 | ||||
8650 | /// Convenience function. LVal's base must be a call to an alloc_size | |||
8651 | /// function. | |||
8652 | static bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx, | |||
8653 | const LValue &LVal, | |||
8654 | llvm::APInt &Result) { | |||
8655 | assert(isBaseAnAllocSizeCall(LVal.getLValueBase()) &&(static_cast <bool> (isBaseAnAllocSizeCall(LVal.getLValueBase ()) && "Can't get the size of a non alloc_size function" ) ? void (0) : __assert_fail ("isBaseAnAllocSizeCall(LVal.getLValueBase()) && \"Can't get the size of a non alloc_size function\"" , "clang/lib/AST/ExprConstant.cpp", 8656, __extension__ __PRETTY_FUNCTION__ )) | |||
8656 | "Can't get the size of a non alloc_size function")(static_cast <bool> (isBaseAnAllocSizeCall(LVal.getLValueBase ()) && "Can't get the size of a non alloc_size function" ) ? void (0) : __assert_fail ("isBaseAnAllocSizeCall(LVal.getLValueBase()) && \"Can't get the size of a non alloc_size function\"" , "clang/lib/AST/ExprConstant.cpp", 8656, __extension__ __PRETTY_FUNCTION__ )); | |||
8657 | const auto *Base = LVal.getLValueBase().get<const Expr *>(); | |||
8658 | const CallExpr *CE = tryUnwrapAllocSizeCall(Base); | |||
8659 | return getBytesReturnedByAllocSizeCall(Ctx, CE, Result); | |||
8660 | } | |||
8661 | ||||
8662 | /// Attempts to evaluate the given LValueBase as the result of a call to | |||
8663 | /// a function with the alloc_size attribute. If it was possible to do so, this | |||
8664 | /// function will return true, make Result's Base point to said function call, | |||
8665 | /// and mark Result's Base as invalid. | |||
8666 | static bool evaluateLValueAsAllocSize(EvalInfo &Info, APValue::LValueBase Base, | |||
8667 | LValue &Result) { | |||
8668 | if (Base.isNull()) | |||
8669 | return false; | |||
8670 | ||||
8671 | // Because we do no form of static analysis, we only support const variables. | |||
8672 | // | |||
8673 | // Additionally, we can't support parameters, nor can we support static | |||
8674 | // variables (in the latter case, use-before-assign isn't UB; in the former, | |||
8675 | // we have no clue what they'll be assigned to). | |||
8676 | const auto *VD = | |||
8677 | dyn_cast_or_null<VarDecl>(Base.dyn_cast<const ValueDecl *>()); | |||
8678 | if (!VD || !VD->isLocalVarDecl() || !VD->getType().isConstQualified()) | |||
8679 | return false; | |||
8680 | ||||
8681 | const Expr *Init = VD->getAnyInitializer(); | |||
8682 | if (!Init || Init->getType().isNull()) | |||
8683 | return false; | |||
8684 | ||||
8685 | const Expr *E = Init->IgnoreParens(); | |||
8686 | if (!tryUnwrapAllocSizeCall(E)) | |||
8687 | return false; | |||
8688 | ||||
8689 | // Store E instead of E unwrapped so that the type of the LValue's base is | |||
8690 | // what the user wanted. | |||
8691 | Result.setInvalid(E); | |||
8692 | ||||
8693 | QualType Pointee = E->getType()->castAs<PointerType>()->getPointeeType(); | |||
8694 | Result.addUnsizedArray(Info, E, Pointee); | |||
8695 | return true; | |||
8696 | } | |||
8697 | ||||
8698 | namespace { | |||
8699 | class PointerExprEvaluator | |||
8700 | : public ExprEvaluatorBase<PointerExprEvaluator> { | |||
8701 | LValue &Result; | |||
8702 | bool InvalidBaseOK; | |||
8703 | ||||
8704 | bool Success(const Expr *E) { | |||
8705 | Result.set(E); | |||
8706 | return true; | |||
8707 | } | |||
8708 | ||||
8709 | bool evaluateLValue(const Expr *E, LValue &Result) { | |||
8710 | return EvaluateLValue(E, Result, Info, InvalidBaseOK); | |||
8711 | } | |||
8712 | ||||
8713 | bool evaluatePointer(const Expr *E, LValue &Result) { | |||
8714 | return EvaluatePointer(E, Result, Info, InvalidBaseOK); | |||
8715 | } | |||
8716 | ||||
8717 | bool visitNonBuiltinCallExpr(const CallExpr *E); | |||
8718 | public: | |||
8719 | ||||
8720 | PointerExprEvaluator(EvalInfo &info, LValue &Result, bool InvalidBaseOK) | |||
8721 | : ExprEvaluatorBaseTy(info), Result(Result), | |||
8722 | InvalidBaseOK(InvalidBaseOK) {} | |||
8723 | ||||
8724 | bool Success(const APValue &V, const Expr *E) { | |||
8725 | Result.setFrom(Info.Ctx, V); | |||
8726 | return true; | |||
8727 | } | |||
8728 | bool ZeroInitialization(const Expr *E) { | |||
8729 | Result.setNull(Info.Ctx, E->getType()); | |||
8730 | return true; | |||
8731 | } | |||
8732 | ||||
8733 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
8734 | bool VisitCastExpr(const CastExpr* E); | |||
8735 | bool VisitUnaryAddrOf(const UnaryOperator *E); | |||
8736 | bool VisitObjCStringLiteral(const ObjCStringLiteral *E) | |||
8737 | { return Success(E); } | |||
8738 | bool VisitObjCBoxedExpr(const ObjCBoxedExpr *E) { | |||
8739 | if (E->isExpressibleAsConstantInitializer()) | |||
8740 | return Success(E); | |||
8741 | if (Info.noteFailure()) | |||
8742 | EvaluateIgnoredValue(Info, E->getSubExpr()); | |||
8743 | return Error(E); | |||
8744 | } | |||
8745 | bool VisitAddrLabelExpr(const AddrLabelExpr *E) | |||
8746 | { return Success(E); } | |||
8747 | bool VisitCallExpr(const CallExpr *E); | |||
8748 | bool VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp); | |||
8749 | bool VisitBlockExpr(const BlockExpr *E) { | |||
8750 | if (!E->getBlockDecl()->hasCaptures()) | |||
8751 | return Success(E); | |||
8752 | return Error(E); | |||
8753 | } | |||
8754 | bool VisitCXXThisExpr(const CXXThisExpr *E) { | |||
8755 | // Can't look at 'this' when checking a potential constant expression. | |||
8756 | if (Info.checkingPotentialConstantExpression()) | |||
8757 | return false; | |||
8758 | if (!Info.CurrentCall->This) { | |||
8759 | if (Info.getLangOpts().CPlusPlus11) | |||
8760 | Info.FFDiag(E, diag::note_constexpr_this) << E->isImplicit(); | |||
8761 | else | |||
8762 | Info.FFDiag(E); | |||
8763 | return false; | |||
8764 | } | |||
8765 | Result = *Info.CurrentCall->This; | |||
8766 | ||||
8767 | if (isLambdaCallOperator(Info.CurrentCall->Callee)) { | |||
8768 | // Ensure we actually have captured 'this'. If something was wrong with | |||
8769 | // 'this' capture, the error would have been previously reported. | |||
8770 | // Otherwise we can be inside of a default initialization of an object | |||
8771 | // declared by lambda's body, so no need to return false. | |||
8772 | if (!Info.CurrentCall->LambdaThisCaptureField) | |||
8773 | return true; | |||
8774 | ||||
8775 | // If we have captured 'this', the 'this' expression refers | |||
8776 | // to the enclosing '*this' object (either by value or reference) which is | |||
8777 | // either copied into the closure object's field that represents the | |||
8778 | // '*this' or refers to '*this'. | |||
8779 | // Update 'Result' to refer to the data member/field of the closure object | |||
8780 | // that represents the '*this' capture. | |||
8781 | if (!HandleLValueMember(Info, E, Result, | |||
8782 | Info.CurrentCall->LambdaThisCaptureField)) | |||
8783 | return false; | |||
8784 | // If we captured '*this' by reference, replace the field with its referent. | |||
8785 | if (Info.CurrentCall->LambdaThisCaptureField->getType() | |||
8786 | ->isPointerType()) { | |||
8787 | APValue RVal; | |||
8788 | if (!handleLValueToRValueConversion(Info, E, E->getType(), Result, | |||
8789 | RVal)) | |||
8790 | return false; | |||
8791 | ||||
8792 | Result.setFrom(Info.Ctx, RVal); | |||
8793 | } | |||
8794 | } | |||
8795 | return true; | |||
8796 | } | |||
8797 | ||||
8798 | bool VisitCXXNewExpr(const CXXNewExpr *E); | |||
8799 | ||||
8800 | bool VisitSourceLocExpr(const SourceLocExpr *E) { | |||
8801 | assert(!E->isIntType() && "SourceLocExpr isn't a pointer type?")(static_cast <bool> (!E->isIntType() && "SourceLocExpr isn't a pointer type?" ) ? void (0) : __assert_fail ("!E->isIntType() && \"SourceLocExpr isn't a pointer type?\"" , "clang/lib/AST/ExprConstant.cpp", 8801, __extension__ __PRETTY_FUNCTION__ )); | |||
8802 | APValue LValResult = E->EvaluateInContext( | |||
8803 | Info.Ctx, Info.CurrentCall->CurSourceLocExprScope.getDefaultExpr()); | |||
8804 | Result.setFrom(Info.Ctx, LValResult); | |||
8805 | return true; | |||
8806 | } | |||
8807 | ||||
8808 | bool VisitSYCLUniqueStableNameExpr(const SYCLUniqueStableNameExpr *E) { | |||
8809 | std::string ResultStr = E->ComputeName(Info.Ctx); | |||
8810 | ||||
8811 | QualType CharTy = Info.Ctx.CharTy.withConst(); | |||
8812 | APInt Size(Info.Ctx.getTypeSize(Info.Ctx.getSizeType()), | |||
8813 | ResultStr.size() + 1); | |||
8814 | QualType ArrayTy = Info.Ctx.getConstantArrayType(CharTy, Size, nullptr, | |||
8815 | ArrayType::Normal, 0); | |||
8816 | ||||
8817 | StringLiteral *SL = | |||
8818 | StringLiteral::Create(Info.Ctx, ResultStr, StringLiteral::Ordinary, | |||
8819 | /*Pascal*/ false, ArrayTy, E->getLocation()); | |||
8820 | ||||
8821 | evaluateLValue(SL, Result); | |||
8822 | Result.addArray(Info, E, cast<ConstantArrayType>(ArrayTy)); | |||
8823 | return true; | |||
8824 | } | |||
8825 | ||||
8826 | // FIXME: Missing: @protocol, @selector | |||
8827 | }; | |||
8828 | } // end anonymous namespace | |||
8829 | ||||
8830 | static bool EvaluatePointer(const Expr* E, LValue& Result, EvalInfo &Info, | |||
8831 | bool InvalidBaseOK) { | |||
8832 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 8832, __extension__ __PRETTY_FUNCTION__)); | |||
8833 | assert(E->isPRValue() && E->getType()->hasPointerRepresentation())(static_cast <bool> (E->isPRValue() && E-> getType()->hasPointerRepresentation()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->hasPointerRepresentation()" , "clang/lib/AST/ExprConstant.cpp", 8833, __extension__ __PRETTY_FUNCTION__ )); | |||
8834 | return PointerExprEvaluator(Info, Result, InvalidBaseOK).Visit(E); | |||
8835 | } | |||
8836 | ||||
8837 | bool PointerExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
8838 | if (E->getOpcode() != BO_Add && | |||
8839 | E->getOpcode() != BO_Sub) | |||
8840 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
8841 | ||||
8842 | const Expr *PExp = E->getLHS(); | |||
8843 | const Expr *IExp = E->getRHS(); | |||
8844 | if (IExp->getType()->isPointerType()) | |||
8845 | std::swap(PExp, IExp); | |||
8846 | ||||
8847 | bool EvalPtrOK = evaluatePointer(PExp, Result); | |||
8848 | if (!EvalPtrOK && !Info.noteFailure()) | |||
8849 | return false; | |||
8850 | ||||
8851 | llvm::APSInt Offset; | |||
8852 | if (!EvaluateInteger(IExp, Offset, Info) || !EvalPtrOK) | |||
8853 | return false; | |||
8854 | ||||
8855 | if (E->getOpcode() == BO_Sub) | |||
8856 | negateAsSigned(Offset); | |||
8857 | ||||
8858 | QualType Pointee = PExp->getType()->castAs<PointerType>()->getPointeeType(); | |||
8859 | return HandleLValueArrayAdjustment(Info, E, Result, Pointee, Offset); | |||
8860 | } | |||
8861 | ||||
8862 | bool PointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) { | |||
8863 | return evaluateLValue(E->getSubExpr(), Result); | |||
8864 | } | |||
8865 | ||||
8866 | // Is the provided decl 'std::source_location::current'? | |||
8867 | static bool IsDeclSourceLocationCurrent(const FunctionDecl *FD) { | |||
8868 | if (!FD) | |||
8869 | return false; | |||
8870 | const IdentifierInfo *FnII = FD->getIdentifier(); | |||
8871 | if (!FnII || !FnII->isStr("current")) | |||
8872 | return false; | |||
8873 | ||||
8874 | const auto *RD = dyn_cast<RecordDecl>(FD->getParent()); | |||
8875 | if (!RD) | |||
8876 | return false; | |||
8877 | ||||
8878 | const IdentifierInfo *ClassII = RD->getIdentifier(); | |||
8879 | return RD->isInStdNamespace() && ClassII && ClassII->isStr("source_location"); | |||
8880 | } | |||
8881 | ||||
8882 | bool PointerExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
8883 | const Expr *SubExpr = E->getSubExpr(); | |||
8884 | ||||
8885 | switch (E->getCastKind()) { | |||
8886 | default: | |||
8887 | break; | |||
8888 | case CK_BitCast: | |||
8889 | case CK_CPointerToObjCPointerCast: | |||
8890 | case CK_BlockPointerToObjCPointerCast: | |||
8891 | case CK_AnyPointerToBlockPointerCast: | |||
8892 | case CK_AddressSpaceConversion: | |||
8893 | if (!Visit(SubExpr)) | |||
8894 | return false; | |||
8895 | // Bitcasts to cv void* are static_casts, not reinterpret_casts, so are | |||
8896 | // permitted in constant expressions in C++11. Bitcasts from cv void* are | |||
8897 | // also static_casts, but we disallow them as a resolution to DR1312. | |||
8898 | if (!E->getType()->isVoidPointerType()) { | |||
8899 | // In some circumstances, we permit casting from void* to cv1 T*, when the | |||
8900 | // actual pointee object is actually a cv2 T. | |||
8901 | bool VoidPtrCastMaybeOK = | |||
8902 | !Result.InvalidBase && !Result.Designator.Invalid && | |||
8903 | !Result.IsNullPtr && | |||
8904 | Info.Ctx.hasSameUnqualifiedType(Result.Designator.getType(Info.Ctx), | |||
8905 | E->getType()->getPointeeType()); | |||
8906 | // 1. We'll allow it in std::allocator::allocate, and anything which that | |||
8907 | // calls. | |||
8908 | // 2. HACK 2022-03-28: Work around an issue with libstdc++'s | |||
8909 | // <source_location> header. Fixed in GCC 12 and later (2022-04-??). | |||
8910 | // We'll allow it in the body of std::source_location::current. GCC's | |||
8911 | // implementation had a parameter of type `void*`, and casts from | |||
8912 | // that back to `const __impl*` in its body. | |||
8913 | if (VoidPtrCastMaybeOK && | |||
8914 | (Info.getStdAllocatorCaller("allocate") || | |||
8915 | IsDeclSourceLocationCurrent(Info.CurrentCall->Callee))) { | |||
8916 | // Permitted. | |||
8917 | } else { | |||
8918 | Result.Designator.setInvalid(); | |||
8919 | if (SubExpr->getType()->isVoidPointerType()) | |||
8920 | CCEDiag(E, diag::note_constexpr_invalid_cast) | |||
8921 | << 3 << SubExpr->getType(); | |||
8922 | else | |||
8923 | CCEDiag(E, diag::note_constexpr_invalid_cast) | |||
8924 | << 2 << Info.Ctx.getLangOpts().CPlusPlus; | |||
8925 | } | |||
8926 | } | |||
8927 | if (E->getCastKind() == CK_AddressSpaceConversion && Result.IsNullPtr) | |||
8928 | ZeroInitialization(E); | |||
8929 | return true; | |||
8930 | ||||
8931 | case CK_DerivedToBase: | |||
8932 | case CK_UncheckedDerivedToBase: | |||
8933 | if (!evaluatePointer(E->getSubExpr(), Result)) | |||
8934 | return false; | |||
8935 | if (!Result.Base && Result.Offset.isZero()) | |||
8936 | return true; | |||
8937 | ||||
8938 | // Now figure out the necessary offset to add to the base LV to get from | |||
8939 | // the derived class to the base class. | |||
8940 | return HandleLValueBasePath(Info, E, E->getSubExpr()->getType()-> | |||
8941 | castAs<PointerType>()->getPointeeType(), | |||
8942 | Result); | |||
8943 | ||||
8944 | case CK_BaseToDerived: | |||
8945 | if (!Visit(E->getSubExpr())) | |||
8946 | return false; | |||
8947 | if (!Result.Base && Result.Offset.isZero()) | |||
8948 | return true; | |||
8949 | return HandleBaseToDerivedCast(Info, E, Result); | |||
8950 | ||||
8951 | case CK_Dynamic: | |||
8952 | if (!Visit(E->getSubExpr())) | |||
8953 | return false; | |||
8954 | return HandleDynamicCast(Info, cast<ExplicitCastExpr>(E), Result); | |||
8955 | ||||
8956 | case CK_NullToPointer: | |||
8957 | VisitIgnoredValue(E->getSubExpr()); | |||
8958 | return ZeroInitialization(E); | |||
8959 | ||||
8960 | case CK_IntegralToPointer: { | |||
8961 | CCEDiag(E, diag::note_constexpr_invalid_cast) | |||
8962 | << 2 << Info.Ctx.getLangOpts().CPlusPlus; | |||
8963 | ||||
8964 | APValue Value; | |||
8965 | if (!EvaluateIntegerOrLValue(SubExpr, Value, Info)) | |||
8966 | break; | |||
8967 | ||||
8968 | if (Value.isInt()) { | |||
8969 | unsigned Size = Info.Ctx.getTypeSize(E->getType()); | |||
8970 | uint64_t N = Value.getInt().extOrTrunc(Size).getZExtValue(); | |||
8971 | Result.Base = (Expr*)nullptr; | |||
8972 | Result.InvalidBase = false; | |||
8973 | Result.Offset = CharUnits::fromQuantity(N); | |||
8974 | Result.Designator.setInvalid(); | |||
8975 | Result.IsNullPtr = false; | |||
8976 | return true; | |||
8977 | } else { | |||
8978 | // Cast is of an lvalue, no need to change value. | |||
8979 | Result.setFrom(Info.Ctx, Value); | |||
8980 | return true; | |||
8981 | } | |||
8982 | } | |||
8983 | ||||
8984 | case CK_ArrayToPointerDecay: { | |||
8985 | if (SubExpr->isGLValue()) { | |||
8986 | if (!evaluateLValue(SubExpr, Result)) | |||
8987 | return false; | |||
8988 | } else { | |||
8989 | APValue &Value = Info.CurrentCall->createTemporary( | |||
8990 | SubExpr, SubExpr->getType(), ScopeKind::FullExpression, Result); | |||
8991 | if (!EvaluateInPlace(Value, Info, Result, SubExpr)) | |||
8992 | return false; | |||
8993 | } | |||
8994 | // The result is a pointer to the first element of the array. | |||
8995 | auto *AT = Info.Ctx.getAsArrayType(SubExpr->getType()); | |||
8996 | if (auto *CAT = dyn_cast<ConstantArrayType>(AT)) | |||
8997 | Result.addArray(Info, E, CAT); | |||
8998 | else | |||
8999 | Result.addUnsizedArray(Info, E, AT->getElementType()); | |||
9000 | return true; | |||
9001 | } | |||
9002 | ||||
9003 | case CK_FunctionToPointerDecay: | |||
9004 | return evaluateLValue(SubExpr, Result); | |||
9005 | ||||
9006 | case CK_LValueToRValue: { | |||
9007 | LValue LVal; | |||
9008 | if (!evaluateLValue(E->getSubExpr(), LVal)) | |||
9009 | return false; | |||
9010 | ||||
9011 | APValue RVal; | |||
9012 | // Note, we use the subexpression's type in order to retain cv-qualifiers. | |||
9013 | if (!handleLValueToRValueConversion(Info, E, E->getSubExpr()->getType(), | |||
9014 | LVal, RVal)) | |||
9015 | return InvalidBaseOK && | |||
9016 | evaluateLValueAsAllocSize(Info, LVal.Base, Result); | |||
9017 | return Success(RVal, E); | |||
9018 | } | |||
9019 | } | |||
9020 | ||||
9021 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
9022 | } | |||
9023 | ||||
9024 | static CharUnits GetAlignOfType(EvalInfo &Info, QualType T, | |||
9025 | UnaryExprOrTypeTrait ExprKind) { | |||
9026 | // C++ [expr.alignof]p3: | |||
9027 | // When alignof is applied to a reference type, the result is the | |||
9028 | // alignment of the referenced type. | |||
9029 | if (const ReferenceType *Ref = T->getAs<ReferenceType>()) | |||
9030 | T = Ref->getPointeeType(); | |||
9031 | ||||
9032 | if (T.getQualifiers().hasUnaligned()) | |||
9033 | return CharUnits::One(); | |||
9034 | ||||
9035 | const bool AlignOfReturnsPreferred = | |||
9036 | Info.Ctx.getLangOpts().getClangABICompat() <= LangOptions::ClangABI::Ver7; | |||
9037 | ||||
9038 | // __alignof is defined to return the preferred alignment. | |||
9039 | // Before 8, clang returned the preferred alignment for alignof and _Alignof | |||
9040 | // as well. | |||
9041 | if (ExprKind == UETT_PreferredAlignOf || AlignOfReturnsPreferred) | |||
9042 | return Info.Ctx.toCharUnitsFromBits( | |||
9043 | Info.Ctx.getPreferredTypeAlign(T.getTypePtr())); | |||
9044 | // alignof and _Alignof are defined to return the ABI alignment. | |||
9045 | else if (ExprKind == UETT_AlignOf) | |||
9046 | return Info.Ctx.getTypeAlignInChars(T.getTypePtr()); | |||
9047 | else | |||
9048 | llvm_unreachable("GetAlignOfType on a non-alignment ExprKind")::llvm::llvm_unreachable_internal("GetAlignOfType on a non-alignment ExprKind" , "clang/lib/AST/ExprConstant.cpp", 9048); | |||
9049 | } | |||
9050 | ||||
9051 | static CharUnits GetAlignOfExpr(EvalInfo &Info, const Expr *E, | |||
9052 | UnaryExprOrTypeTrait ExprKind) { | |||
9053 | E = E->IgnoreParens(); | |||
9054 | ||||
9055 | // The kinds of expressions that we have special-case logic here for | |||
9056 | // should be kept up to date with the special checks for those | |||
9057 | // expressions in Sema. | |||
9058 | ||||
9059 | // alignof decl is always accepted, even if it doesn't make sense: we default | |||
9060 | // to 1 in those cases. | |||
9061 | if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) | |||
9062 | return Info.Ctx.getDeclAlign(DRE->getDecl(), | |||
9063 | /*RefAsPointee*/true); | |||
9064 | ||||
9065 | if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) | |||
9066 | return Info.Ctx.getDeclAlign(ME->getMemberDecl(), | |||
9067 | /*RefAsPointee*/true); | |||
9068 | ||||
9069 | return GetAlignOfType(Info, E->getType(), ExprKind); | |||
9070 | } | |||
9071 | ||||
9072 | static CharUnits getBaseAlignment(EvalInfo &Info, const LValue &Value) { | |||
9073 | if (const auto *VD = Value.Base.dyn_cast<const ValueDecl *>()) | |||
9074 | return Info.Ctx.getDeclAlign(VD); | |||
9075 | if (const auto *E = Value.Base.dyn_cast<const Expr *>()) | |||
9076 | return GetAlignOfExpr(Info, E, UETT_AlignOf); | |||
9077 | return GetAlignOfType(Info, Value.Base.getTypeInfoType(), UETT_AlignOf); | |||
9078 | } | |||
9079 | ||||
9080 | /// Evaluate the value of the alignment argument to __builtin_align_{up,down}, | |||
9081 | /// __builtin_is_aligned and __builtin_assume_aligned. | |||
9082 | static bool getAlignmentArgument(const Expr *E, QualType ForType, | |||
9083 | EvalInfo &Info, APSInt &Alignment) { | |||
9084 | if (!EvaluateInteger(E, Alignment, Info)) | |||
9085 | return false; | |||
9086 | if (Alignment < 0 || !Alignment.isPowerOf2()) { | |||
9087 | Info.FFDiag(E, diag::note_constexpr_invalid_alignment) << Alignment; | |||
9088 | return false; | |||
9089 | } | |||
9090 | unsigned SrcWidth = Info.Ctx.getIntWidth(ForType); | |||
9091 | APSInt MaxValue(APInt::getOneBitSet(SrcWidth, SrcWidth - 1)); | |||
9092 | if (APSInt::compareValues(Alignment, MaxValue) > 0) { | |||
9093 | Info.FFDiag(E, diag::note_constexpr_alignment_too_big) | |||
9094 | << MaxValue << ForType << Alignment; | |||
9095 | return false; | |||
9096 | } | |||
9097 | // Ensure both alignment and source value have the same bit width so that we | |||
9098 | // don't assert when computing the resulting value. | |||
9099 | APSInt ExtAlignment = | |||
9100 | APSInt(Alignment.zextOrTrunc(SrcWidth), /*isUnsigned=*/true); | |||
9101 | assert(APSInt::compareValues(Alignment, ExtAlignment) == 0 &&(static_cast <bool> (APSInt::compareValues(Alignment, ExtAlignment ) == 0 && "Alignment should not be changed by ext/trunc" ) ? void (0) : __assert_fail ("APSInt::compareValues(Alignment, ExtAlignment) == 0 && \"Alignment should not be changed by ext/trunc\"" , "clang/lib/AST/ExprConstant.cpp", 9102, __extension__ __PRETTY_FUNCTION__ )) | |||
9102 | "Alignment should not be changed by ext/trunc")(static_cast <bool> (APSInt::compareValues(Alignment, ExtAlignment ) == 0 && "Alignment should not be changed by ext/trunc" ) ? void (0) : __assert_fail ("APSInt::compareValues(Alignment, ExtAlignment) == 0 && \"Alignment should not be changed by ext/trunc\"" , "clang/lib/AST/ExprConstant.cpp", 9102, __extension__ __PRETTY_FUNCTION__ )); | |||
9103 | Alignment = ExtAlignment; | |||
9104 | assert(Alignment.getBitWidth() == SrcWidth)(static_cast <bool> (Alignment.getBitWidth() == SrcWidth ) ? void (0) : __assert_fail ("Alignment.getBitWidth() == SrcWidth" , "clang/lib/AST/ExprConstant.cpp", 9104, __extension__ __PRETTY_FUNCTION__ )); | |||
9105 | return true; | |||
9106 | } | |||
9107 | ||||
9108 | // To be clear: this happily visits unsupported builtins. Better name welcomed. | |||
9109 | bool PointerExprEvaluator::visitNonBuiltinCallExpr(const CallExpr *E) { | |||
9110 | if (ExprEvaluatorBaseTy::VisitCallExpr(E)) | |||
9111 | return true; | |||
9112 | ||||
9113 | if (!(InvalidBaseOK && getAllocSizeAttr(E))) | |||
9114 | return false; | |||
9115 | ||||
9116 | Result.setInvalid(E); | |||
9117 | QualType PointeeTy = E->getType()->castAs<PointerType>()->getPointeeType(); | |||
9118 | Result.addUnsizedArray(Info, E, PointeeTy); | |||
9119 | return true; | |||
9120 | } | |||
9121 | ||||
9122 | bool PointerExprEvaluator::VisitCallExpr(const CallExpr *E) { | |||
9123 | if (!IsConstantEvaluatedBuiltinCall(E)) | |||
9124 | return visitNonBuiltinCallExpr(E); | |||
9125 | return VisitBuiltinCallExpr(E, E->getBuiltinCallee()); | |||
9126 | } | |||
9127 | ||||
9128 | // Determine if T is a character type for which we guarantee that | |||
9129 | // sizeof(T) == 1. | |||
9130 | static bool isOneByteCharacterType(QualType T) { | |||
9131 | return T->isCharType() || T->isChar8Type(); | |||
9132 | } | |||
9133 | ||||
9134 | bool PointerExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E, | |||
9135 | unsigned BuiltinOp) { | |||
9136 | if (IsNoOpCall(E)) | |||
9137 | return Success(E); | |||
9138 | ||||
9139 | switch (BuiltinOp) { | |||
9140 | case Builtin::BIaddressof: | |||
9141 | case Builtin::BI__addressof: | |||
9142 | case Builtin::BI__builtin_addressof: | |||
9143 | return evaluateLValue(E->getArg(0), Result); | |||
9144 | case Builtin::BI__builtin_assume_aligned: { | |||
9145 | // We need to be very careful here because: if the pointer does not have the | |||
9146 | // asserted alignment, then the behavior is undefined, and undefined | |||
9147 | // behavior is non-constant. | |||
9148 | if (!evaluatePointer(E->getArg(0), Result)) | |||
9149 | return false; | |||
9150 | ||||
9151 | LValue OffsetResult(Result); | |||
9152 | APSInt Alignment; | |||
9153 | if (!getAlignmentArgument(E->getArg(1), E->getArg(0)->getType(), Info, | |||
9154 | Alignment)) | |||
9155 | return false; | |||
9156 | CharUnits Align = CharUnits::fromQuantity(Alignment.getZExtValue()); | |||
9157 | ||||
9158 | if (E->getNumArgs() > 2) { | |||
9159 | APSInt Offset; | |||
9160 | if (!EvaluateInteger(E->getArg(2), Offset, Info)) | |||
9161 | return false; | |||
9162 | ||||
9163 | int64_t AdditionalOffset = -Offset.getZExtValue(); | |||
9164 | OffsetResult.Offset += CharUnits::fromQuantity(AdditionalOffset); | |||
9165 | } | |||
9166 | ||||
9167 | // If there is a base object, then it must have the correct alignment. | |||
9168 | if (OffsetResult.Base) { | |||
9169 | CharUnits BaseAlignment = getBaseAlignment(Info, OffsetResult); | |||
9170 | ||||
9171 | if (BaseAlignment < Align) { | |||
9172 | Result.Designator.setInvalid(); | |||
9173 | // FIXME: Add support to Diagnostic for long / long long. | |||
9174 | CCEDiag(E->getArg(0), | |||
9175 | diag::note_constexpr_baa_insufficient_alignment) << 0 | |||
9176 | << (unsigned)BaseAlignment.getQuantity() | |||
9177 | << (unsigned)Align.getQuantity(); | |||
9178 | return false; | |||
9179 | } | |||
9180 | } | |||
9181 | ||||
9182 | // The offset must also have the correct alignment. | |||
9183 | if (OffsetResult.Offset.alignTo(Align) != OffsetResult.Offset) { | |||
9184 | Result.Designator.setInvalid(); | |||
9185 | ||||
9186 | (OffsetResult.Base | |||
9187 | ? CCEDiag(E->getArg(0), | |||
9188 | diag::note_constexpr_baa_insufficient_alignment) << 1 | |||
9189 | : CCEDiag(E->getArg(0), | |||
9190 | diag::note_constexpr_baa_value_insufficient_alignment)) | |||
9191 | << (int)OffsetResult.Offset.getQuantity() | |||
9192 | << (unsigned)Align.getQuantity(); | |||
9193 | return false; | |||
9194 | } | |||
9195 | ||||
9196 | return true; | |||
9197 | } | |||
9198 | case Builtin::BI__builtin_align_up: | |||
9199 | case Builtin::BI__builtin_align_down: { | |||
9200 | if (!evaluatePointer(E->getArg(0), Result)) | |||
9201 | return false; | |||
9202 | APSInt Alignment; | |||
9203 | if (!getAlignmentArgument(E->getArg(1), E->getArg(0)->getType(), Info, | |||
9204 | Alignment)) | |||
9205 | return false; | |||
9206 | CharUnits BaseAlignment = getBaseAlignment(Info, Result); | |||
9207 | CharUnits PtrAlign = BaseAlignment.alignmentAtOffset(Result.Offset); | |||
9208 | // For align_up/align_down, we can return the same value if the alignment | |||
9209 | // is known to be greater or equal to the requested value. | |||
9210 | if (PtrAlign.getQuantity() >= Alignment) | |||
9211 | return true; | |||
9212 | ||||
9213 | // The alignment could be greater than the minimum at run-time, so we cannot | |||
9214 | // infer much about the resulting pointer value. One case is possible: | |||
9215 | // For `_Alignas(32) char buf[N]; __builtin_align_down(&buf[idx], 32)` we | |||
9216 | // can infer the correct index if the requested alignment is smaller than | |||
9217 | // the base alignment so we can perform the computation on the offset. | |||
9218 | if (BaseAlignment.getQuantity() >= Alignment) { | |||
9219 | assert(Alignment.getBitWidth() <= 64 &&(static_cast <bool> (Alignment.getBitWidth() <= 64 && "Cannot handle > 64-bit address-space") ? void (0) : __assert_fail ("Alignment.getBitWidth() <= 64 && \"Cannot handle > 64-bit address-space\"" , "clang/lib/AST/ExprConstant.cpp", 9220, __extension__ __PRETTY_FUNCTION__ )) | |||
9220 | "Cannot handle > 64-bit address-space")(static_cast <bool> (Alignment.getBitWidth() <= 64 && "Cannot handle > 64-bit address-space") ? void (0) : __assert_fail ("Alignment.getBitWidth() <= 64 && \"Cannot handle > 64-bit address-space\"" , "clang/lib/AST/ExprConstant.cpp", 9220, __extension__ __PRETTY_FUNCTION__ )); | |||
9221 | uint64_t Alignment64 = Alignment.getZExtValue(); | |||
9222 | CharUnits NewOffset = CharUnits::fromQuantity( | |||
9223 | BuiltinOp == Builtin::BI__builtin_align_down | |||
9224 | ? llvm::alignDown(Result.Offset.getQuantity(), Alignment64) | |||
9225 | : llvm::alignTo(Result.Offset.getQuantity(), Alignment64)); | |||
9226 | Result.adjustOffset(NewOffset - Result.Offset); | |||
9227 | // TODO: diagnose out-of-bounds values/only allow for arrays? | |||
9228 | return true; | |||
9229 | } | |||
9230 | // Otherwise, we cannot constant-evaluate the result. | |||
9231 | Info.FFDiag(E->getArg(0), diag::note_constexpr_alignment_adjust) | |||
9232 | << Alignment; | |||
9233 | return false; | |||
9234 | } | |||
9235 | case Builtin::BI__builtin_operator_new: | |||
9236 | return HandleOperatorNewCall(Info, E, Result); | |||
9237 | case Builtin::BI__builtin_launder: | |||
9238 | return evaluatePointer(E->getArg(0), Result); | |||
9239 | case Builtin::BIstrchr: | |||
9240 | case Builtin::BIwcschr: | |||
9241 | case Builtin::BImemchr: | |||
9242 | case Builtin::BIwmemchr: | |||
9243 | if (Info.getLangOpts().CPlusPlus11) | |||
9244 | Info.CCEDiag(E, diag::note_constexpr_invalid_function) | |||
9245 | << /*isConstexpr*/ 0 << /*isConstructor*/ 0 | |||
9246 | << ("'" + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'").str(); | |||
9247 | else | |||
9248 | Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
9249 | [[fallthrough]]; | |||
9250 | case Builtin::BI__builtin_strchr: | |||
9251 | case Builtin::BI__builtin_wcschr: | |||
9252 | case Builtin::BI__builtin_memchr: | |||
9253 | case Builtin::BI__builtin_char_memchr: | |||
9254 | case Builtin::BI__builtin_wmemchr: { | |||
9255 | if (!Visit(E->getArg(0))) | |||
9256 | return false; | |||
9257 | APSInt Desired; | |||
9258 | if (!EvaluateInteger(E->getArg(1), Desired, Info)) | |||
9259 | return false; | |||
9260 | uint64_t MaxLength = uint64_t(-1); | |||
9261 | if (BuiltinOp != Builtin::BIstrchr && | |||
9262 | BuiltinOp != Builtin::BIwcschr && | |||
9263 | BuiltinOp != Builtin::BI__builtin_strchr && | |||
9264 | BuiltinOp != Builtin::BI__builtin_wcschr) { | |||
9265 | APSInt N; | |||
9266 | if (!EvaluateInteger(E->getArg(2), N, Info)) | |||
9267 | return false; | |||
9268 | MaxLength = N.getExtValue(); | |||
9269 | } | |||
9270 | // We cannot find the value if there are no candidates to match against. | |||
9271 | if (MaxLength == 0u) | |||
9272 | return ZeroInitialization(E); | |||
9273 | if (!Result.checkNullPointerForFoldAccess(Info, E, AK_Read) || | |||
9274 | Result.Designator.Invalid) | |||
9275 | return false; | |||
9276 | QualType CharTy = Result.Designator.getType(Info.Ctx); | |||
9277 | bool IsRawByte = BuiltinOp == Builtin::BImemchr || | |||
9278 | BuiltinOp == Builtin::BI__builtin_memchr; | |||
9279 | assert(IsRawByte ||(static_cast <bool> (IsRawByte || Info.Ctx.hasSameUnqualifiedType ( CharTy, E->getArg(0)->getType()->getPointeeType()) ) ? void (0) : __assert_fail ("IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E->getArg(0)->getType()->getPointeeType())" , "clang/lib/AST/ExprConstant.cpp", 9281, __extension__ __PRETTY_FUNCTION__ )) | |||
9280 | Info.Ctx.hasSameUnqualifiedType((static_cast <bool> (IsRawByte || Info.Ctx.hasSameUnqualifiedType ( CharTy, E->getArg(0)->getType()->getPointeeType()) ) ? void (0) : __assert_fail ("IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E->getArg(0)->getType()->getPointeeType())" , "clang/lib/AST/ExprConstant.cpp", 9281, __extension__ __PRETTY_FUNCTION__ )) | |||
9281 | CharTy, E->getArg(0)->getType()->getPointeeType()))(static_cast <bool> (IsRawByte || Info.Ctx.hasSameUnqualifiedType ( CharTy, E->getArg(0)->getType()->getPointeeType()) ) ? void (0) : __assert_fail ("IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E->getArg(0)->getType()->getPointeeType())" , "clang/lib/AST/ExprConstant.cpp", 9281, __extension__ __PRETTY_FUNCTION__ )); | |||
9282 | // Pointers to const void may point to objects of incomplete type. | |||
9283 | if (IsRawByte && CharTy->isIncompleteType()) { | |||
9284 | Info.FFDiag(E, diag::note_constexpr_ltor_incomplete_type) << CharTy; | |||
9285 | return false; | |||
9286 | } | |||
9287 | // Give up on byte-oriented matching against multibyte elements. | |||
9288 | // FIXME: We can compare the bytes in the correct order. | |||
9289 | if (IsRawByte && !isOneByteCharacterType(CharTy)) { | |||
9290 | Info.FFDiag(E, diag::note_constexpr_memchr_unsupported) | |||
9291 | << ("'" + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'").str() | |||
9292 | << CharTy; | |||
9293 | return false; | |||
9294 | } | |||
9295 | // Figure out what value we're actually looking for (after converting to | |||
9296 | // the corresponding unsigned type if necessary). | |||
9297 | uint64_t DesiredVal; | |||
9298 | bool StopAtNull = false; | |||
9299 | switch (BuiltinOp) { | |||
9300 | case Builtin::BIstrchr: | |||
9301 | case Builtin::BI__builtin_strchr: | |||
9302 | // strchr compares directly to the passed integer, and therefore | |||
9303 | // always fails if given an int that is not a char. | |||
9304 | if (!APSInt::isSameValue(HandleIntToIntCast(Info, E, CharTy, | |||
9305 | E->getArg(1)->getType(), | |||
9306 | Desired), | |||
9307 | Desired)) | |||
9308 | return ZeroInitialization(E); | |||
9309 | StopAtNull = true; | |||
9310 | [[fallthrough]]; | |||
9311 | case Builtin::BImemchr: | |||
9312 | case Builtin::BI__builtin_memchr: | |||
9313 | case Builtin::BI__builtin_char_memchr: | |||
9314 | // memchr compares by converting both sides to unsigned char. That's also | |||
9315 | // correct for strchr if we get this far (to cope with plain char being | |||
9316 | // unsigned in the strchr case). | |||
9317 | DesiredVal = Desired.trunc(Info.Ctx.getCharWidth()).getZExtValue(); | |||
9318 | break; | |||
9319 | ||||
9320 | case Builtin::BIwcschr: | |||
9321 | case Builtin::BI__builtin_wcschr: | |||
9322 | StopAtNull = true; | |||
9323 | [[fallthrough]]; | |||
9324 | case Builtin::BIwmemchr: | |||
9325 | case Builtin::BI__builtin_wmemchr: | |||
9326 | // wcschr and wmemchr are given a wchar_t to look for. Just use it. | |||
9327 | DesiredVal = Desired.getZExtValue(); | |||
9328 | break; | |||
9329 | } | |||
9330 | ||||
9331 | for (; MaxLength; --MaxLength) { | |||
9332 | APValue Char; | |||
9333 | if (!handleLValueToRValueConversion(Info, E, CharTy, Result, Char) || | |||
9334 | !Char.isInt()) | |||
9335 | return false; | |||
9336 | if (Char.getInt().getZExtValue() == DesiredVal) | |||
9337 | return true; | |||
9338 | if (StopAtNull && !Char.getInt()) | |||
9339 | break; | |||
9340 | if (!HandleLValueArrayAdjustment(Info, E, Result, CharTy, 1)) | |||
9341 | return false; | |||
9342 | } | |||
9343 | // Not found: return nullptr. | |||
9344 | return ZeroInitialization(E); | |||
9345 | } | |||
9346 | ||||
9347 | case Builtin::BImemcpy: | |||
9348 | case Builtin::BImemmove: | |||
9349 | case Builtin::BIwmemcpy: | |||
9350 | case Builtin::BIwmemmove: | |||
9351 | if (Info.getLangOpts().CPlusPlus11) | |||
9352 | Info.CCEDiag(E, diag::note_constexpr_invalid_function) | |||
9353 | << /*isConstexpr*/ 0 << /*isConstructor*/ 0 | |||
9354 | << ("'" + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'").str(); | |||
9355 | else | |||
9356 | Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
9357 | [[fallthrough]]; | |||
9358 | case Builtin::BI__builtin_memcpy: | |||
9359 | case Builtin::BI__builtin_memmove: | |||
9360 | case Builtin::BI__builtin_wmemcpy: | |||
9361 | case Builtin::BI__builtin_wmemmove: { | |||
9362 | bool WChar = BuiltinOp == Builtin::BIwmemcpy || | |||
9363 | BuiltinOp == Builtin::BIwmemmove || | |||
9364 | BuiltinOp == Builtin::BI__builtin_wmemcpy || | |||
9365 | BuiltinOp == Builtin::BI__builtin_wmemmove; | |||
9366 | bool Move = BuiltinOp == Builtin::BImemmove || | |||
9367 | BuiltinOp == Builtin::BIwmemmove || | |||
9368 | BuiltinOp == Builtin::BI__builtin_memmove || | |||
9369 | BuiltinOp == Builtin::BI__builtin_wmemmove; | |||
9370 | ||||
9371 | // The result of mem* is the first argument. | |||
9372 | if (!Visit(E->getArg(0))) | |||
9373 | return false; | |||
9374 | LValue Dest = Result; | |||
9375 | ||||
9376 | LValue Src; | |||
9377 | if (!EvaluatePointer(E->getArg(1), Src, Info)) | |||
9378 | return false; | |||
9379 | ||||
9380 | APSInt N; | |||
9381 | if (!EvaluateInteger(E->getArg(2), N, Info)) | |||
9382 | return false; | |||
9383 | assert(!N.isSigned() && "memcpy and friends take an unsigned size")(static_cast <bool> (!N.isSigned() && "memcpy and friends take an unsigned size" ) ? void (0) : __assert_fail ("!N.isSigned() && \"memcpy and friends take an unsigned size\"" , "clang/lib/AST/ExprConstant.cpp", 9383, __extension__ __PRETTY_FUNCTION__ )); | |||
9384 | ||||
9385 | // If the size is zero, we treat this as always being a valid no-op. | |||
9386 | // (Even if one of the src and dest pointers is null.) | |||
9387 | if (!N) | |||
9388 | return true; | |||
9389 | ||||
9390 | // Otherwise, if either of the operands is null, we can't proceed. Don't | |||
9391 | // try to determine the type of the copied objects, because there aren't | |||
9392 | // any. | |||
9393 | if (!Src.Base || !Dest.Base) { | |||
9394 | APValue Val; | |||
9395 | (!Src.Base ? Src : Dest).moveInto(Val); | |||
9396 | Info.FFDiag(E, diag::note_constexpr_memcpy_null) | |||
9397 | << Move << WChar << !!Src.Base | |||
9398 | << Val.getAsString(Info.Ctx, E->getArg(0)->getType()); | |||
9399 | return false; | |||
9400 | } | |||
9401 | if (Src.Designator.Invalid || Dest.Designator.Invalid) | |||
9402 | return false; | |||
9403 | ||||
9404 | // We require that Src and Dest are both pointers to arrays of | |||
9405 | // trivially-copyable type. (For the wide version, the designator will be | |||
9406 | // invalid if the designated object is not a wchar_t.) | |||
9407 | QualType T = Dest.Designator.getType(Info.Ctx); | |||
9408 | QualType SrcT = Src.Designator.getType(Info.Ctx); | |||
9409 | if (!Info.Ctx.hasSameUnqualifiedType(T, SrcT)) { | |||
9410 | // FIXME: Consider using our bit_cast implementation to support this. | |||
9411 | Info.FFDiag(E, diag::note_constexpr_memcpy_type_pun) << Move << SrcT << T; | |||
9412 | return false; | |||
9413 | } | |||
9414 | if (T->isIncompleteType()) { | |||
9415 | Info.FFDiag(E, diag::note_constexpr_memcpy_incomplete_type) << Move << T; | |||
9416 | return false; | |||
9417 | } | |||
9418 | if (!T.isTriviallyCopyableType(Info.Ctx)) { | |||
9419 | Info.FFDiag(E, diag::note_constexpr_memcpy_nontrivial) << Move << T; | |||
9420 | return false; | |||
9421 | } | |||
9422 | ||||
9423 | // Figure out how many T's we're copying. | |||
9424 | uint64_t TSize = Info.Ctx.getTypeSizeInChars(T).getQuantity(); | |||
9425 | if (!WChar) { | |||
9426 | uint64_t Remainder; | |||
9427 | llvm::APInt OrigN = N; | |||
9428 | llvm::APInt::udivrem(OrigN, TSize, N, Remainder); | |||
9429 | if (Remainder) { | |||
9430 | Info.FFDiag(E, diag::note_constexpr_memcpy_unsupported) | |||
9431 | << Move << WChar << 0 << T << toString(OrigN, 10, /*Signed*/false) | |||
9432 | << (unsigned)TSize; | |||
9433 | return false; | |||
9434 | } | |||
9435 | } | |||
9436 | ||||
9437 | // Check that the copying will remain within the arrays, just so that we | |||
9438 | // can give a more meaningful diagnostic. This implicitly also checks that | |||
9439 | // N fits into 64 bits. | |||
9440 | uint64_t RemainingSrcSize = Src.Designator.validIndexAdjustments().second; | |||
9441 | uint64_t RemainingDestSize = Dest.Designator.validIndexAdjustments().second; | |||
9442 | if (N.ugt(RemainingSrcSize) || N.ugt(RemainingDestSize)) { | |||
9443 | Info.FFDiag(E, diag::note_constexpr_memcpy_unsupported) | |||
9444 | << Move << WChar << (N.ugt(RemainingSrcSize) ? 1 : 2) << T | |||
9445 | << toString(N, 10, /*Signed*/false); | |||
9446 | return false; | |||
9447 | } | |||
9448 | uint64_t NElems = N.getZExtValue(); | |||
9449 | uint64_t NBytes = NElems * TSize; | |||
9450 | ||||
9451 | // Check for overlap. | |||
9452 | int Direction = 1; | |||
9453 | if (HasSameBase(Src, Dest)) { | |||
9454 | uint64_t SrcOffset = Src.getLValueOffset().getQuantity(); | |||
9455 | uint64_t DestOffset = Dest.getLValueOffset().getQuantity(); | |||
9456 | if (DestOffset >= SrcOffset && DestOffset - SrcOffset < NBytes) { | |||
9457 | // Dest is inside the source region. | |||
9458 | if (!Move) { | |||
9459 | Info.FFDiag(E, diag::note_constexpr_memcpy_overlap) << WChar; | |||
9460 | return false; | |||
9461 | } | |||
9462 | // For memmove and friends, copy backwards. | |||
9463 | if (!HandleLValueArrayAdjustment(Info, E, Src, T, NElems - 1) || | |||
9464 | !HandleLValueArrayAdjustment(Info, E, Dest, T, NElems - 1)) | |||
9465 | return false; | |||
9466 | Direction = -1; | |||
9467 | } else if (!Move && SrcOffset >= DestOffset && | |||
9468 | SrcOffset - DestOffset < NBytes) { | |||
9469 | // Src is inside the destination region for memcpy: invalid. | |||
9470 | Info.FFDiag(E, diag::note_constexpr_memcpy_overlap) << WChar; | |||
9471 | return false; | |||
9472 | } | |||
9473 | } | |||
9474 | ||||
9475 | while (true) { | |||
9476 | APValue Val; | |||
9477 | // FIXME: Set WantObjectRepresentation to true if we're copying a | |||
9478 | // char-like type? | |||
9479 | if (!handleLValueToRValueConversion(Info, E, T, Src, Val) || | |||
9480 | !handleAssignment(Info, E, Dest, T, Val)) | |||
9481 | return false; | |||
9482 | // Do not iterate past the last element; if we're copying backwards, that | |||
9483 | // might take us off the start of the array. | |||
9484 | if (--NElems == 0) | |||
9485 | return true; | |||
9486 | if (!HandleLValueArrayAdjustment(Info, E, Src, T, Direction) || | |||
9487 | !HandleLValueArrayAdjustment(Info, E, Dest, T, Direction)) | |||
9488 | return false; | |||
9489 | } | |||
9490 | } | |||
9491 | ||||
9492 | default: | |||
9493 | return false; | |||
9494 | } | |||
9495 | } | |||
9496 | ||||
9497 | static bool EvaluateArrayNewInitList(EvalInfo &Info, LValue &This, | |||
9498 | APValue &Result, const InitListExpr *ILE, | |||
9499 | QualType AllocType); | |||
9500 | static bool EvaluateArrayNewConstructExpr(EvalInfo &Info, LValue &This, | |||
9501 | APValue &Result, | |||
9502 | const CXXConstructExpr *CCE, | |||
9503 | QualType AllocType); | |||
9504 | ||||
9505 | bool PointerExprEvaluator::VisitCXXNewExpr(const CXXNewExpr *E) { | |||
9506 | if (!Info.getLangOpts().CPlusPlus20) | |||
9507 | Info.CCEDiag(E, diag::note_constexpr_new); | |||
9508 | ||||
9509 | // We cannot speculatively evaluate a delete expression. | |||
9510 | if (Info.SpeculativeEvaluationDepth) | |||
9511 | return false; | |||
9512 | ||||
9513 | FunctionDecl *OperatorNew = E->getOperatorNew(); | |||
9514 | ||||
9515 | bool IsNothrow = false; | |||
9516 | bool IsPlacement = false; | |||
9517 | if (OperatorNew->isReservedGlobalPlacementOperator() && | |||
9518 | Info.CurrentCall->isStdFunction() && !E->isArray()) { | |||
9519 | // FIXME Support array placement new. | |||
9520 | assert(E->getNumPlacementArgs() == 1)(static_cast <bool> (E->getNumPlacementArgs() == 1) ? void (0) : __assert_fail ("E->getNumPlacementArgs() == 1" , "clang/lib/AST/ExprConstant.cpp", 9520, __extension__ __PRETTY_FUNCTION__ )); | |||
9521 | if (!EvaluatePointer(E->getPlacementArg(0), Result, Info)) | |||
9522 | return false; | |||
9523 | if (Result.Designator.Invalid) | |||
9524 | return false; | |||
9525 | IsPlacement = true; | |||
9526 | } else if (!OperatorNew->isReplaceableGlobalAllocationFunction()) { | |||
9527 | Info.FFDiag(E, diag::note_constexpr_new_non_replaceable) | |||
9528 | << isa<CXXMethodDecl>(OperatorNew) << OperatorNew; | |||
9529 | return false; | |||
9530 | } else if (E->getNumPlacementArgs()) { | |||
9531 | // The only new-placement list we support is of the form (std::nothrow). | |||
9532 | // | |||
9533 | // FIXME: There is no restriction on this, but it's not clear that any | |||
9534 | // other form makes any sense. We get here for cases such as: | |||
9535 | // | |||
9536 | // new (std::align_val_t{N}) X(int) | |||
9537 | // | |||
9538 | // (which should presumably be valid only if N is a multiple of | |||
9539 | // alignof(int), and in any case can't be deallocated unless N is | |||
9540 | // alignof(X) and X has new-extended alignment). | |||
9541 | if (E->getNumPlacementArgs() != 1 || | |||
9542 | !E->getPlacementArg(0)->getType()->isNothrowT()) | |||
9543 | return Error(E, diag::note_constexpr_new_placement); | |||
9544 | ||||
9545 | LValue Nothrow; | |||
9546 | if (!EvaluateLValue(E->getPlacementArg(0), Nothrow, Info)) | |||
9547 | return false; | |||
9548 | IsNothrow = true; | |||
9549 | } | |||
9550 | ||||
9551 | const Expr *Init = E->getInitializer(); | |||
9552 | const InitListExpr *ResizedArrayILE = nullptr; | |||
9553 | const CXXConstructExpr *ResizedArrayCCE = nullptr; | |||
9554 | bool ValueInit = false; | |||
9555 | ||||
9556 | QualType AllocType = E->getAllocatedType(); | |||
9557 | if (std::optional<const Expr *> ArraySize = E->getArraySize()) { | |||
9558 | const Expr *Stripped = *ArraySize; | |||
9559 | for (; auto *ICE = dyn_cast<ImplicitCastExpr>(Stripped); | |||
9560 | Stripped = ICE->getSubExpr()) | |||
9561 | if (ICE->getCastKind() != CK_NoOp && | |||
9562 | ICE->getCastKind() != CK_IntegralCast) | |||
9563 | break; | |||
9564 | ||||
9565 | llvm::APSInt ArrayBound; | |||
9566 | if (!EvaluateInteger(Stripped, ArrayBound, Info)) | |||
9567 | return false; | |||
9568 | ||||
9569 | // C++ [expr.new]p9: | |||
9570 | // The expression is erroneous if: | |||
9571 | // -- [...] its value before converting to size_t [or] applying the | |||
9572 | // second standard conversion sequence is less than zero | |||
9573 | if (ArrayBound.isSigned() && ArrayBound.isNegative()) { | |||
9574 | if (IsNothrow) | |||
9575 | return ZeroInitialization(E); | |||
9576 | ||||
9577 | Info.FFDiag(*ArraySize, diag::note_constexpr_new_negative) | |||
9578 | << ArrayBound << (*ArraySize)->getSourceRange(); | |||
9579 | return false; | |||
9580 | } | |||
9581 | ||||
9582 | // -- its value is such that the size of the allocated object would | |||
9583 | // exceed the implementation-defined limit | |||
9584 | if (ConstantArrayType::getNumAddressingBits(Info.Ctx, AllocType, | |||
9585 | ArrayBound) > | |||
9586 | ConstantArrayType::getMaxSizeBits(Info.Ctx)) { | |||
9587 | if (IsNothrow) | |||
9588 | return ZeroInitialization(E); | |||
9589 | ||||
9590 | Info.FFDiag(*ArraySize, diag::note_constexpr_new_too_large) | |||
9591 | << ArrayBound << (*ArraySize)->getSourceRange(); | |||
9592 | return false; | |||
9593 | } | |||
9594 | ||||
9595 | // -- the new-initializer is a braced-init-list and the number of | |||
9596 | // array elements for which initializers are provided [...] | |||
9597 | // exceeds the number of elements to initialize | |||
9598 | if (!Init) { | |||
9599 | // No initialization is performed. | |||
9600 | } else if (isa<CXXScalarValueInitExpr>(Init) || | |||
9601 | isa<ImplicitValueInitExpr>(Init)) { | |||
9602 | ValueInit = true; | |||
9603 | } else if (auto *CCE = dyn_cast<CXXConstructExpr>(Init)) { | |||
9604 | ResizedArrayCCE = CCE; | |||
9605 | } else { | |||
9606 | auto *CAT = Info.Ctx.getAsConstantArrayType(Init->getType()); | |||
9607 | assert(CAT && "unexpected type for array initializer")(static_cast <bool> (CAT && "unexpected type for array initializer" ) ? void (0) : __assert_fail ("CAT && \"unexpected type for array initializer\"" , "clang/lib/AST/ExprConstant.cpp", 9607, __extension__ __PRETTY_FUNCTION__ )); | |||
9608 | ||||
9609 | unsigned Bits = | |||
9610 | std::max(CAT->getSize().getBitWidth(), ArrayBound.getBitWidth()); | |||
9611 | llvm::APInt InitBound = CAT->getSize().zext(Bits); | |||
9612 | llvm::APInt AllocBound = ArrayBound.zext(Bits); | |||
9613 | if (InitBound.ugt(AllocBound)) { | |||
9614 | if (IsNothrow) | |||
9615 | return ZeroInitialization(E); | |||
9616 | ||||
9617 | Info.FFDiag(*ArraySize, diag::note_constexpr_new_too_small) | |||
9618 | << toString(AllocBound, 10, /*Signed=*/false) | |||
9619 | << toString(InitBound, 10, /*Signed=*/false) | |||
9620 | << (*ArraySize)->getSourceRange(); | |||
9621 | return false; | |||
9622 | } | |||
9623 | ||||
9624 | // If the sizes differ, we must have an initializer list, and we need | |||
9625 | // special handling for this case when we initialize. | |||
9626 | if (InitBound != AllocBound) | |||
9627 | ResizedArrayILE = cast<InitListExpr>(Init); | |||
9628 | } | |||
9629 | ||||
9630 | AllocType = Info.Ctx.getConstantArrayType(AllocType, ArrayBound, nullptr, | |||
9631 | ArrayType::Normal, 0); | |||
9632 | } else { | |||
9633 | assert(!AllocType->isArrayType() &&(static_cast <bool> (!AllocType->isArrayType() && "array allocation with non-array new") ? void (0) : __assert_fail ("!AllocType->isArrayType() && \"array allocation with non-array new\"" , "clang/lib/AST/ExprConstant.cpp", 9634, __extension__ __PRETTY_FUNCTION__ )) | |||
9634 | "array allocation with non-array new")(static_cast <bool> (!AllocType->isArrayType() && "array allocation with non-array new") ? void (0) : __assert_fail ("!AllocType->isArrayType() && \"array allocation with non-array new\"" , "clang/lib/AST/ExprConstant.cpp", 9634, __extension__ __PRETTY_FUNCTION__ )); | |||
9635 | } | |||
9636 | ||||
9637 | APValue *Val; | |||
9638 | if (IsPlacement) { | |||
9639 | AccessKinds AK = AK_Construct; | |||
9640 | struct FindObjectHandler { | |||
9641 | EvalInfo &Info; | |||
9642 | const Expr *E; | |||
9643 | QualType AllocType; | |||
9644 | const AccessKinds AccessKind; | |||
9645 | APValue *Value; | |||
9646 | ||||
9647 | typedef bool result_type; | |||
9648 | bool failed() { return false; } | |||
9649 | bool found(APValue &Subobj, QualType SubobjType) { | |||
9650 | // FIXME: Reject the cases where [basic.life]p8 would not permit the | |||
9651 | // old name of the object to be used to name the new object. | |||
9652 | if (!Info.Ctx.hasSameUnqualifiedType(SubobjType, AllocType)) { | |||
9653 | Info.FFDiag(E, diag::note_constexpr_placement_new_wrong_type) << | |||
9654 | SubobjType << AllocType; | |||
9655 | return false; | |||
9656 | } | |||
9657 | Value = &Subobj; | |||
9658 | return true; | |||
9659 | } | |||
9660 | bool found(APSInt &Value, QualType SubobjType) { | |||
9661 | Info.FFDiag(E, diag::note_constexpr_construct_complex_elem); | |||
9662 | return false; | |||
9663 | } | |||
9664 | bool found(APFloat &Value, QualType SubobjType) { | |||
9665 | Info.FFDiag(E, diag::note_constexpr_construct_complex_elem); | |||
9666 | return false; | |||
9667 | } | |||
9668 | } Handler = {Info, E, AllocType, AK, nullptr}; | |||
9669 | ||||
9670 | CompleteObject Obj = findCompleteObject(Info, E, AK, Result, AllocType); | |||
9671 | if (!Obj || !findSubobject(Info, E, Obj, Result.Designator, Handler)) | |||
9672 | return false; | |||
9673 | ||||
9674 | Val = Handler.Value; | |||
9675 | ||||
9676 | // [basic.life]p1: | |||
9677 | // The lifetime of an object o of type T ends when [...] the storage | |||
9678 | // which the object occupies is [...] reused by an object that is not | |||
9679 | // nested within o (6.6.2). | |||
9680 | *Val = APValue(); | |||
9681 | } else { | |||
9682 | // Perform the allocation and obtain a pointer to the resulting object. | |||
9683 | Val = Info.createHeapAlloc(E, AllocType, Result); | |||
9684 | if (!Val) | |||
9685 | return false; | |||
9686 | } | |||
9687 | ||||
9688 | if (ValueInit) { | |||
9689 | ImplicitValueInitExpr VIE(AllocType); | |||
9690 | if (!EvaluateInPlace(*Val, Info, Result, &VIE)) | |||
9691 | return false; | |||
9692 | } else if (ResizedArrayILE) { | |||
9693 | if (!EvaluateArrayNewInitList(Info, Result, *Val, ResizedArrayILE, | |||
9694 | AllocType)) | |||
9695 | return false; | |||
9696 | } else if (ResizedArrayCCE) { | |||
9697 | if (!EvaluateArrayNewConstructExpr(Info, Result, *Val, ResizedArrayCCE, | |||
9698 | AllocType)) | |||
9699 | return false; | |||
9700 | } else if (Init) { | |||
9701 | if (!EvaluateInPlace(*Val, Info, Result, Init)) | |||
9702 | return false; | |||
9703 | } else if (!getDefaultInitValue(AllocType, *Val)) { | |||
9704 | return false; | |||
9705 | } | |||
9706 | ||||
9707 | // Array new returns a pointer to the first element, not a pointer to the | |||
9708 | // array. | |||
9709 | if (auto *AT = AllocType->getAsArrayTypeUnsafe()) | |||
9710 | Result.addArray(Info, E, cast<ConstantArrayType>(AT)); | |||
9711 | ||||
9712 | return true; | |||
9713 | } | |||
9714 | //===----------------------------------------------------------------------===// | |||
9715 | // Member Pointer Evaluation | |||
9716 | //===----------------------------------------------------------------------===// | |||
9717 | ||||
9718 | namespace { | |||
9719 | class MemberPointerExprEvaluator | |||
9720 | : public ExprEvaluatorBase<MemberPointerExprEvaluator> { | |||
9721 | MemberPtr &Result; | |||
9722 | ||||
9723 | bool Success(const ValueDecl *D) { | |||
9724 | Result = MemberPtr(D); | |||
9725 | return true; | |||
9726 | } | |||
9727 | public: | |||
9728 | ||||
9729 | MemberPointerExprEvaluator(EvalInfo &Info, MemberPtr &Result) | |||
9730 | : ExprEvaluatorBaseTy(Info), Result(Result) {} | |||
9731 | ||||
9732 | bool Success(const APValue &V, const Expr *E) { | |||
9733 | Result.setFrom(V); | |||
9734 | return true; | |||
9735 | } | |||
9736 | bool ZeroInitialization(const Expr *E) { | |||
9737 | return Success((const ValueDecl*)nullptr); | |||
9738 | } | |||
9739 | ||||
9740 | bool VisitCastExpr(const CastExpr *E); | |||
9741 | bool VisitUnaryAddrOf(const UnaryOperator *E); | |||
9742 | }; | |||
9743 | } // end anonymous namespace | |||
9744 | ||||
9745 | static bool EvaluateMemberPointer(const Expr *E, MemberPtr &Result, | |||
9746 | EvalInfo &Info) { | |||
9747 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 9747, __extension__ __PRETTY_FUNCTION__)); | |||
9748 | assert(E->isPRValue() && E->getType()->isMemberPointerType())(static_cast <bool> (E->isPRValue() && E-> getType()->isMemberPointerType()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isMemberPointerType()" , "clang/lib/AST/ExprConstant.cpp", 9748, __extension__ __PRETTY_FUNCTION__ )); | |||
9749 | return MemberPointerExprEvaluator(Info, Result).Visit(E); | |||
9750 | } | |||
9751 | ||||
9752 | bool MemberPointerExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
9753 | switch (E->getCastKind()) { | |||
9754 | default: | |||
9755 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
9756 | ||||
9757 | case CK_NullToMemberPointer: | |||
9758 | VisitIgnoredValue(E->getSubExpr()); | |||
9759 | return ZeroInitialization(E); | |||
9760 | ||||
9761 | case CK_BaseToDerivedMemberPointer: { | |||
9762 | if (!Visit(E->getSubExpr())) | |||
9763 | return false; | |||
9764 | if (E->path_empty()) | |||
9765 | return true; | |||
9766 | // Base-to-derived member pointer casts store the path in derived-to-base | |||
9767 | // order, so iterate backwards. The CXXBaseSpecifier also provides us with | |||
9768 | // the wrong end of the derived->base arc, so stagger the path by one class. | |||
9769 | typedef std::reverse_iterator<CastExpr::path_const_iterator> ReverseIter; | |||
9770 | for (ReverseIter PathI(E->path_end() - 1), PathE(E->path_begin()); | |||
9771 | PathI != PathE; ++PathI) { | |||
9772 | assert(!(*PathI)->isVirtual() && "memptr cast through vbase")(static_cast <bool> (!(*PathI)->isVirtual() && "memptr cast through vbase") ? void (0) : __assert_fail ("!(*PathI)->isVirtual() && \"memptr cast through vbase\"" , "clang/lib/AST/ExprConstant.cpp", 9772, __extension__ __PRETTY_FUNCTION__ )); | |||
9773 | const CXXRecordDecl *Derived = (*PathI)->getType()->getAsCXXRecordDecl(); | |||
9774 | if (!Result.castToDerived(Derived)) | |||
9775 | return Error(E); | |||
9776 | } | |||
9777 | const Type *FinalTy = E->getType()->castAs<MemberPointerType>()->getClass(); | |||
9778 | if (!Result.castToDerived(FinalTy->getAsCXXRecordDecl())) | |||
9779 | return Error(E); | |||
9780 | return true; | |||
9781 | } | |||
9782 | ||||
9783 | case CK_DerivedToBaseMemberPointer: | |||
9784 | if (!Visit(E->getSubExpr())) | |||
9785 | return false; | |||
9786 | for (CastExpr::path_const_iterator PathI = E->path_begin(), | |||
9787 | PathE = E->path_end(); PathI != PathE; ++PathI) { | |||
9788 | assert(!(*PathI)->isVirtual() && "memptr cast through vbase")(static_cast <bool> (!(*PathI)->isVirtual() && "memptr cast through vbase") ? void (0) : __assert_fail ("!(*PathI)->isVirtual() && \"memptr cast through vbase\"" , "clang/lib/AST/ExprConstant.cpp", 9788, __extension__ __PRETTY_FUNCTION__ )); | |||
9789 | const CXXRecordDecl *Base = (*PathI)->getType()->getAsCXXRecordDecl(); | |||
9790 | if (!Result.castToBase(Base)) | |||
9791 | return Error(E); | |||
9792 | } | |||
9793 | return true; | |||
9794 | } | |||
9795 | } | |||
9796 | ||||
9797 | bool MemberPointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) { | |||
9798 | // C++11 [expr.unary.op]p3 has very strict rules on how the address of a | |||
9799 | // member can be formed. | |||
9800 | return Success(cast<DeclRefExpr>(E->getSubExpr())->getDecl()); | |||
9801 | } | |||
9802 | ||||
9803 | //===----------------------------------------------------------------------===// | |||
9804 | // Record Evaluation | |||
9805 | //===----------------------------------------------------------------------===// | |||
9806 | ||||
9807 | namespace { | |||
9808 | class RecordExprEvaluator | |||
9809 | : public ExprEvaluatorBase<RecordExprEvaluator> { | |||
9810 | const LValue &This; | |||
9811 | APValue &Result; | |||
9812 | public: | |||
9813 | ||||
9814 | RecordExprEvaluator(EvalInfo &info, const LValue &This, APValue &Result) | |||
9815 | : ExprEvaluatorBaseTy(info), This(This), Result(Result) {} | |||
9816 | ||||
9817 | bool Success(const APValue &V, const Expr *E) { | |||
9818 | Result = V; | |||
9819 | return true; | |||
9820 | } | |||
9821 | bool ZeroInitialization(const Expr *E) { | |||
9822 | return ZeroInitialization(E, E->getType()); | |||
9823 | } | |||
9824 | bool ZeroInitialization(const Expr *E, QualType T); | |||
9825 | ||||
9826 | bool VisitCallExpr(const CallExpr *E) { | |||
9827 | return handleCallExpr(E, Result, &This); | |||
9828 | } | |||
9829 | bool VisitCastExpr(const CastExpr *E); | |||
9830 | bool VisitInitListExpr(const InitListExpr *E); | |||
9831 | bool VisitCXXConstructExpr(const CXXConstructExpr *E) { | |||
9832 | return VisitCXXConstructExpr(E, E->getType()); | |||
9833 | } | |||
9834 | bool VisitLambdaExpr(const LambdaExpr *E); | |||
9835 | bool VisitCXXInheritedCtorInitExpr(const CXXInheritedCtorInitExpr *E); | |||
9836 | bool VisitCXXConstructExpr(const CXXConstructExpr *E, QualType T); | |||
9837 | bool VisitCXXStdInitializerListExpr(const CXXStdInitializerListExpr *E); | |||
9838 | bool VisitBinCmp(const BinaryOperator *E); | |||
9839 | bool VisitCXXParenListInitExpr(const CXXParenListInitExpr *E); | |||
9840 | bool VisitCXXParenListOrInitListExpr(const Expr *ExprToVisit, | |||
9841 | ArrayRef<Expr *> Args); | |||
9842 | }; | |||
9843 | } | |||
9844 | ||||
9845 | /// Perform zero-initialization on an object of non-union class type. | |||
9846 | /// C++11 [dcl.init]p5: | |||
9847 | /// To zero-initialize an object or reference of type T means: | |||
9848 | /// [...] | |||
9849 | /// -- if T is a (possibly cv-qualified) non-union class type, | |||
9850 | /// each non-static data member and each base-class subobject is | |||
9851 | /// zero-initialized | |||
9852 | static bool HandleClassZeroInitialization(EvalInfo &Info, const Expr *E, | |||
9853 | const RecordDecl *RD, | |||
9854 | const LValue &This, APValue &Result) { | |||
9855 | assert(!RD->isUnion() && "Expected non-union class type")(static_cast <bool> (!RD->isUnion() && "Expected non-union class type" ) ? void (0) : __assert_fail ("!RD->isUnion() && \"Expected non-union class type\"" , "clang/lib/AST/ExprConstant.cpp", 9855, __extension__ __PRETTY_FUNCTION__ )); | |||
9856 | const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD); | |||
9857 | Result = APValue(APValue::UninitStruct(), CD ? CD->getNumBases() : 0, | |||
9858 | std::distance(RD->field_begin(), RD->field_end())); | |||
9859 | ||||
9860 | if (RD->isInvalidDecl()) return false; | |||
9861 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
9862 | ||||
9863 | if (CD) { | |||
9864 | unsigned Index = 0; | |||
9865 | for (CXXRecordDecl::base_class_const_iterator I = CD->bases_begin(), | |||
9866 | End = CD->bases_end(); I != End; ++I, ++Index) { | |||
9867 | const CXXRecordDecl *Base = I->getType()->getAsCXXRecordDecl(); | |||
9868 | LValue Subobject = This; | |||
9869 | if (!HandleLValueDirectBase(Info, E, Subobject, CD, Base, &Layout)) | |||
9870 | return false; | |||
9871 | if (!HandleClassZeroInitialization(Info, E, Base, Subobject, | |||
9872 | Result.getStructBase(Index))) | |||
9873 | return false; | |||
9874 | } | |||
9875 | } | |||
9876 | ||||
9877 | for (const auto *I : RD->fields()) { | |||
9878 | // -- if T is a reference type, no initialization is performed. | |||
9879 | if (I->isUnnamedBitfield() || I->getType()->isReferenceType()) | |||
9880 | continue; | |||
9881 | ||||
9882 | LValue Subobject = This; | |||
9883 | if (!HandleLValueMember(Info, E, Subobject, I, &Layout)) | |||
9884 | return false; | |||
9885 | ||||
9886 | ImplicitValueInitExpr VIE(I->getType()); | |||
9887 | if (!EvaluateInPlace( | |||
9888 | Result.getStructField(I->getFieldIndex()), Info, Subobject, &VIE)) | |||
9889 | return false; | |||
9890 | } | |||
9891 | ||||
9892 | return true; | |||
9893 | } | |||
9894 | ||||
9895 | bool RecordExprEvaluator::ZeroInitialization(const Expr *E, QualType T) { | |||
9896 | const RecordDecl *RD = T->castAs<RecordType>()->getDecl(); | |||
9897 | if (RD->isInvalidDecl()) return false; | |||
9898 | if (RD->isUnion()) { | |||
9899 | // C++11 [dcl.init]p5: If T is a (possibly cv-qualified) union type, the | |||
9900 | // object's first non-static named data member is zero-initialized | |||
9901 | RecordDecl::field_iterator I = RD->field_begin(); | |||
9902 | while (I != RD->field_end() && (*I)->isUnnamedBitfield()) | |||
9903 | ++I; | |||
9904 | if (I == RD->field_end()) { | |||
9905 | Result = APValue((const FieldDecl*)nullptr); | |||
9906 | return true; | |||
9907 | } | |||
9908 | ||||
9909 | LValue Subobject = This; | |||
9910 | if (!HandleLValueMember(Info, E, Subobject, *I)) | |||
9911 | return false; | |||
9912 | Result = APValue(*I); | |||
9913 | ImplicitValueInitExpr VIE(I->getType()); | |||
9914 | return EvaluateInPlace(Result.getUnionValue(), Info, Subobject, &VIE); | |||
9915 | } | |||
9916 | ||||
9917 | if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->getNumVBases()) { | |||
9918 | Info.FFDiag(E, diag::note_constexpr_virtual_base) << RD; | |||
9919 | return false; | |||
9920 | } | |||
9921 | ||||
9922 | return HandleClassZeroInitialization(Info, E, RD, This, Result); | |||
9923 | } | |||
9924 | ||||
9925 | bool RecordExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
9926 | switch (E->getCastKind()) { | |||
9927 | default: | |||
9928 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
9929 | ||||
9930 | case CK_ConstructorConversion: | |||
9931 | return Visit(E->getSubExpr()); | |||
9932 | ||||
9933 | case CK_DerivedToBase: | |||
9934 | case CK_UncheckedDerivedToBase: { | |||
9935 | APValue DerivedObject; | |||
9936 | if (!Evaluate(DerivedObject, Info, E->getSubExpr())) | |||
9937 | return false; | |||
9938 | if (!DerivedObject.isStruct()) | |||
9939 | return Error(E->getSubExpr()); | |||
9940 | ||||
9941 | // Derived-to-base rvalue conversion: just slice off the derived part. | |||
9942 | APValue *Value = &DerivedObject; | |||
9943 | const CXXRecordDecl *RD = E->getSubExpr()->getType()->getAsCXXRecordDecl(); | |||
9944 | for (CastExpr::path_const_iterator PathI = E->path_begin(), | |||
9945 | PathE = E->path_end(); PathI != PathE; ++PathI) { | |||
9946 | assert(!(*PathI)->isVirtual() && "record rvalue with virtual base")(static_cast <bool> (!(*PathI)->isVirtual() && "record rvalue with virtual base") ? void (0) : __assert_fail ("!(*PathI)->isVirtual() && \"record rvalue with virtual base\"" , "clang/lib/AST/ExprConstant.cpp", 9946, __extension__ __PRETTY_FUNCTION__ )); | |||
9947 | const CXXRecordDecl *Base = (*PathI)->getType()->getAsCXXRecordDecl(); | |||
9948 | Value = &Value->getStructBase(getBaseIndex(RD, Base)); | |||
9949 | RD = Base; | |||
9950 | } | |||
9951 | Result = *Value; | |||
9952 | return true; | |||
9953 | } | |||
9954 | } | |||
9955 | } | |||
9956 | ||||
9957 | bool RecordExprEvaluator::VisitInitListExpr(const InitListExpr *E) { | |||
9958 | if (E->isTransparent()) | |||
9959 | return Visit(E->getInit(0)); | |||
9960 | return VisitCXXParenListOrInitListExpr(E, E->inits()); | |||
9961 | } | |||
9962 | ||||
9963 | bool RecordExprEvaluator::VisitCXXParenListOrInitListExpr( | |||
9964 | const Expr *ExprToVisit, ArrayRef<Expr *> Args) { | |||
9965 | const RecordDecl *RD = | |||
9966 | ExprToVisit->getType()->castAs<RecordType>()->getDecl(); | |||
9967 | if (RD->isInvalidDecl()) return false; | |||
9968 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
9969 | auto *CXXRD = dyn_cast<CXXRecordDecl>(RD); | |||
9970 | ||||
9971 | EvalInfo::EvaluatingConstructorRAII EvalObj( | |||
9972 | Info, | |||
9973 | ObjectUnderConstruction{This.getLValueBase(), This.Designator.Entries}, | |||
9974 | CXXRD && CXXRD->getNumBases()); | |||
9975 | ||||
9976 | if (RD->isUnion()) { | |||
9977 | const FieldDecl *Field; | |||
9978 | if (auto *ILE = dyn_cast<InitListExpr>(ExprToVisit)) { | |||
9979 | Field = ILE->getInitializedFieldInUnion(); | |||
9980 | } else if (auto *PLIE = dyn_cast<CXXParenListInitExpr>(ExprToVisit)) { | |||
9981 | Field = PLIE->getInitializedFieldInUnion(); | |||
9982 | } else { | |||
9983 | llvm_unreachable(::llvm::llvm_unreachable_internal("Expression is neither an init list nor a C++ paren list" , "clang/lib/AST/ExprConstant.cpp", 9984) | |||
9984 | "Expression is neither an init list nor a C++ paren list")::llvm::llvm_unreachable_internal("Expression is neither an init list nor a C++ paren list" , "clang/lib/AST/ExprConstant.cpp", 9984); | |||
9985 | } | |||
9986 | ||||
9987 | Result = APValue(Field); | |||
9988 | if (!Field) | |||
9989 | return true; | |||
9990 | ||||
9991 | // If the initializer list for a union does not contain any elements, the | |||
9992 | // first element of the union is value-initialized. | |||
9993 | // FIXME: The element should be initialized from an initializer list. | |||
9994 | // Is this difference ever observable for initializer lists which | |||
9995 | // we don't build? | |||
9996 | ImplicitValueInitExpr VIE(Field->getType()); | |||
9997 | const Expr *InitExpr = Args.empty() ? &VIE : Args[0]; | |||
9998 | ||||
9999 | LValue Subobject = This; | |||
10000 | if (!HandleLValueMember(Info, InitExpr, Subobject, Field, &Layout)) | |||
10001 | return false; | |||
10002 | ||||
10003 | // Temporarily override This, in case there's a CXXDefaultInitExpr in here. | |||
10004 | ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This, | |||
10005 | isa<CXXDefaultInitExpr>(InitExpr)); | |||
10006 | ||||
10007 | if (EvaluateInPlace(Result.getUnionValue(), Info, Subobject, InitExpr)) { | |||
10008 | if (Field->isBitField()) | |||
10009 | return truncateBitfieldValue(Info, InitExpr, Result.getUnionValue(), | |||
10010 | Field); | |||
10011 | return true; | |||
10012 | } | |||
10013 | ||||
10014 | return false; | |||
10015 | } | |||
10016 | ||||
10017 | if (!Result.hasValue()) | |||
10018 | Result = APValue(APValue::UninitStruct(), CXXRD ? CXXRD->getNumBases() : 0, | |||
10019 | std::distance(RD->field_begin(), RD->field_end())); | |||
10020 | unsigned ElementNo = 0; | |||
10021 | bool Success = true; | |||
10022 | ||||
10023 | // Initialize base classes. | |||
10024 | if (CXXRD && CXXRD->getNumBases()) { | |||
10025 | for (const auto &Base : CXXRD->bases()) { | |||
10026 | assert(ElementNo < Args.size() && "missing init for base class")(static_cast <bool> (ElementNo < Args.size() && "missing init for base class") ? void (0) : __assert_fail ("ElementNo < Args.size() && \"missing init for base class\"" , "clang/lib/AST/ExprConstant.cpp", 10026, __extension__ __PRETTY_FUNCTION__ )); | |||
10027 | const Expr *Init = Args[ElementNo]; | |||
10028 | ||||
10029 | LValue Subobject = This; | |||
10030 | if (!HandleLValueBase(Info, Init, Subobject, CXXRD, &Base)) | |||
10031 | return false; | |||
10032 | ||||
10033 | APValue &FieldVal = Result.getStructBase(ElementNo); | |||
10034 | if (!EvaluateInPlace(FieldVal, Info, Subobject, Init)) { | |||
10035 | if (!Info.noteFailure()) | |||
10036 | return false; | |||
10037 | Success = false; | |||
10038 | } | |||
10039 | ++ElementNo; | |||
10040 | } | |||
10041 | ||||
10042 | EvalObj.finishedConstructingBases(); | |||
10043 | } | |||
10044 | ||||
10045 | // Initialize members. | |||
10046 | for (const auto *Field : RD->fields()) { | |||
10047 | // Anonymous bit-fields are not considered members of the class for | |||
10048 | // purposes of aggregate initialization. | |||
10049 | if (Field->isUnnamedBitfield()) | |||
10050 | continue; | |||
10051 | ||||
10052 | LValue Subobject = This; | |||
10053 | ||||
10054 | bool HaveInit = ElementNo < Args.size(); | |||
10055 | ||||
10056 | // FIXME: Diagnostics here should point to the end of the initializer | |||
10057 | // list, not the start. | |||
10058 | if (!HandleLValueMember(Info, HaveInit ? Args[ElementNo] : ExprToVisit, | |||
10059 | Subobject, Field, &Layout)) | |||
10060 | return false; | |||
10061 | ||||
10062 | // Perform an implicit value-initialization for members beyond the end of | |||
10063 | // the initializer list. | |||
10064 | ImplicitValueInitExpr VIE(HaveInit ? Info.Ctx.IntTy : Field->getType()); | |||
10065 | const Expr *Init = HaveInit ? Args[ElementNo++] : &VIE; | |||
10066 | ||||
10067 | if (Field->getType()->isIncompleteArrayType()) { | |||
10068 | if (auto *CAT = Info.Ctx.getAsConstantArrayType(Init->getType())) { | |||
10069 | if (!CAT->getSize().isZero()) { | |||
10070 | // Bail out for now. This might sort of "work", but the rest of the | |||
10071 | // code isn't really prepared to handle it. | |||
10072 | Info.FFDiag(Init, diag::note_constexpr_unsupported_flexible_array); | |||
10073 | return false; | |||
10074 | } | |||
10075 | } | |||
10076 | } | |||
10077 | ||||
10078 | // Temporarily override This, in case there's a CXXDefaultInitExpr in here. | |||
10079 | ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This, | |||
10080 | isa<CXXDefaultInitExpr>(Init)); | |||
10081 | ||||
10082 | APValue &FieldVal = Result.getStructField(Field->getFieldIndex()); | |||
10083 | if (!EvaluateInPlace(FieldVal, Info, Subobject, Init) || | |||
10084 | (Field->isBitField() && !truncateBitfieldValue(Info, Init, | |||
10085 | FieldVal, Field))) { | |||
10086 | if (!Info.noteFailure()) | |||
10087 | return false; | |||
10088 | Success = false; | |||
10089 | } | |||
10090 | } | |||
10091 | ||||
10092 | EvalObj.finishedConstructingFields(); | |||
10093 | ||||
10094 | return Success; | |||
10095 | } | |||
10096 | ||||
10097 | bool RecordExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E, | |||
10098 | QualType T) { | |||
10099 | // Note that E's type is not necessarily the type of our class here; we might | |||
10100 | // be initializing an array element instead. | |||
10101 | const CXXConstructorDecl *FD = E->getConstructor(); | |||
10102 | if (FD->isInvalidDecl() || FD->getParent()->isInvalidDecl()) return false; | |||
10103 | ||||
10104 | bool ZeroInit = E->requiresZeroInitialization(); | |||
10105 | if (CheckTrivialDefaultConstructor(Info, E->getExprLoc(), FD, ZeroInit)) { | |||
10106 | // If we've already performed zero-initialization, we're already done. | |||
10107 | if (Result.hasValue()) | |||
10108 | return true; | |||
10109 | ||||
10110 | if (ZeroInit) | |||
10111 | return ZeroInitialization(E, T); | |||
10112 | ||||
10113 | return getDefaultInitValue(T, Result); | |||
10114 | } | |||
10115 | ||||
10116 | const FunctionDecl *Definition = nullptr; | |||
10117 | auto Body = FD->getBody(Definition); | |||
10118 | ||||
10119 | if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body)) | |||
10120 | return false; | |||
10121 | ||||
10122 | // Avoid materializing a temporary for an elidable copy/move constructor. | |||
10123 | if (E->isElidable() && !ZeroInit) { | |||
10124 | // FIXME: This only handles the simplest case, where the source object | |||
10125 | // is passed directly as the first argument to the constructor. | |||
10126 | // This should also handle stepping though implicit casts and | |||
10127 | // and conversion sequences which involve two steps, with a | |||
10128 | // conversion operator followed by a converting constructor. | |||
10129 | const Expr *SrcObj = E->getArg(0); | |||
10130 | assert(SrcObj->isTemporaryObject(Info.Ctx, FD->getParent()))(static_cast <bool> (SrcObj->isTemporaryObject(Info. Ctx, FD->getParent())) ? void (0) : __assert_fail ("SrcObj->isTemporaryObject(Info.Ctx, FD->getParent())" , "clang/lib/AST/ExprConstant.cpp", 10130, __extension__ __PRETTY_FUNCTION__ )); | |||
10131 | assert(Info.Ctx.hasSameUnqualifiedType(E->getType(), SrcObj->getType()))(static_cast <bool> (Info.Ctx.hasSameUnqualifiedType(E-> getType(), SrcObj->getType())) ? void (0) : __assert_fail ( "Info.Ctx.hasSameUnqualifiedType(E->getType(), SrcObj->getType())" , "clang/lib/AST/ExprConstant.cpp", 10131, __extension__ __PRETTY_FUNCTION__ )); | |||
10132 | if (const MaterializeTemporaryExpr *ME = | |||
10133 | dyn_cast<MaterializeTemporaryExpr>(SrcObj)) | |||
10134 | return Visit(ME->getSubExpr()); | |||
10135 | } | |||
10136 | ||||
10137 | if (ZeroInit && !ZeroInitialization(E, T)) | |||
10138 | return false; | |||
10139 | ||||
10140 | auto Args = llvm::ArrayRef(E->getArgs(), E->getNumArgs()); | |||
10141 | return HandleConstructorCall(E, This, Args, | |||
10142 | cast<CXXConstructorDecl>(Definition), Info, | |||
10143 | Result); | |||
10144 | } | |||
10145 | ||||
10146 | bool RecordExprEvaluator::VisitCXXInheritedCtorInitExpr( | |||
10147 | const CXXInheritedCtorInitExpr *E) { | |||
10148 | if (!Info.CurrentCall) { | |||
10149 | assert(Info.checkingPotentialConstantExpression())(static_cast <bool> (Info.checkingPotentialConstantExpression ()) ? void (0) : __assert_fail ("Info.checkingPotentialConstantExpression()" , "clang/lib/AST/ExprConstant.cpp", 10149, __extension__ __PRETTY_FUNCTION__ )); | |||
10150 | return false; | |||
10151 | } | |||
10152 | ||||
10153 | const CXXConstructorDecl *FD = E->getConstructor(); | |||
10154 | if (FD->isInvalidDecl() || FD->getParent()->isInvalidDecl()) | |||
10155 | return false; | |||
10156 | ||||
10157 | const FunctionDecl *Definition = nullptr; | |||
10158 | auto Body = FD->getBody(Definition); | |||
10159 | ||||
10160 | if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body)) | |||
10161 | return false; | |||
10162 | ||||
10163 | return HandleConstructorCall(E, This, Info.CurrentCall->Arguments, | |||
10164 | cast<CXXConstructorDecl>(Definition), Info, | |||
10165 | Result); | |||
10166 | } | |||
10167 | ||||
10168 | bool RecordExprEvaluator::VisitCXXStdInitializerListExpr( | |||
10169 | const CXXStdInitializerListExpr *E) { | |||
10170 | const ConstantArrayType *ArrayType = | |||
10171 | Info.Ctx.getAsConstantArrayType(E->getSubExpr()->getType()); | |||
10172 | ||||
10173 | LValue Array; | |||
10174 | if (!EvaluateLValue(E->getSubExpr(), Array, Info)) | |||
10175 | return false; | |||
10176 | ||||
10177 | // Get a pointer to the first element of the array. | |||
10178 | Array.addArray(Info, E, ArrayType); | |||
10179 | ||||
10180 | auto InvalidType = [&] { | |||
10181 | Info.FFDiag(E, diag::note_constexpr_unsupported_layout) | |||
10182 | << E->getType(); | |||
10183 | return false; | |||
10184 | }; | |||
10185 | ||||
10186 | // FIXME: Perform the checks on the field types in SemaInit. | |||
10187 | RecordDecl *Record = E->getType()->castAs<RecordType>()->getDecl(); | |||
10188 | RecordDecl::field_iterator Field = Record->field_begin(); | |||
10189 | if (Field == Record->field_end()) | |||
10190 | return InvalidType(); | |||
10191 | ||||
10192 | // Start pointer. | |||
10193 | if (!Field->getType()->isPointerType() || | |||
10194 | !Info.Ctx.hasSameType(Field->getType()->getPointeeType(), | |||
10195 | ArrayType->getElementType())) | |||
10196 | return InvalidType(); | |||
10197 | ||||
10198 | // FIXME: What if the initializer_list type has base classes, etc? | |||
10199 | Result = APValue(APValue::UninitStruct(), 0, 2); | |||
10200 | Array.moveInto(Result.getStructField(0)); | |||
10201 | ||||
10202 | if (++Field == Record->field_end()) | |||
10203 | return InvalidType(); | |||
10204 | ||||
10205 | if (Field->getType()->isPointerType() && | |||
10206 | Info.Ctx.hasSameType(Field->getType()->getPointeeType(), | |||
10207 | ArrayType->getElementType())) { | |||
10208 | // End pointer. | |||
10209 | if (!HandleLValueArrayAdjustment(Info, E, Array, | |||
10210 | ArrayType->getElementType(), | |||
10211 | ArrayType->getSize().getZExtValue())) | |||
10212 | return false; | |||
10213 | Array.moveInto(Result.getStructField(1)); | |||
10214 | } else if (Info.Ctx.hasSameType(Field->getType(), Info.Ctx.getSizeType())) | |||
10215 | // Length. | |||
10216 | Result.getStructField(1) = APValue(APSInt(ArrayType->getSize())); | |||
10217 | else | |||
10218 | return InvalidType(); | |||
10219 | ||||
10220 | if (++Field != Record->field_end()) | |||
10221 | return InvalidType(); | |||
10222 | ||||
10223 | return true; | |||
10224 | } | |||
10225 | ||||
10226 | bool RecordExprEvaluator::VisitLambdaExpr(const LambdaExpr *E) { | |||
10227 | const CXXRecordDecl *ClosureClass = E->getLambdaClass(); | |||
10228 | if (ClosureClass->isInvalidDecl()) | |||
10229 | return false; | |||
10230 | ||||
10231 | const size_t NumFields = | |||
10232 | std::distance(ClosureClass->field_begin(), ClosureClass->field_end()); | |||
10233 | ||||
10234 | assert(NumFields == (size_t)std::distance(E->capture_init_begin(),(static_cast <bool> (NumFields == (size_t)std::distance (E->capture_init_begin(), E->capture_init_end()) && "The number of lambda capture initializers should equal the number of " "fields within the closure type") ? void (0) : __assert_fail ("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\"" , "clang/lib/AST/ExprConstant.cpp", 10237, __extension__ __PRETTY_FUNCTION__ )) | |||
10235 | E->capture_init_end()) &&(static_cast <bool> (NumFields == (size_t)std::distance (E->capture_init_begin(), E->capture_init_end()) && "The number of lambda capture initializers should equal the number of " "fields within the closure type") ? void (0) : __assert_fail ("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\"" , "clang/lib/AST/ExprConstant.cpp", 10237, __extension__ __PRETTY_FUNCTION__ )) | |||
10236 | "The number of lambda capture initializers should equal the number of "(static_cast <bool> (NumFields == (size_t)std::distance (E->capture_init_begin(), E->capture_init_end()) && "The number of lambda capture initializers should equal the number of " "fields within the closure type") ? void (0) : __assert_fail ("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\"" , "clang/lib/AST/ExprConstant.cpp", 10237, __extension__ __PRETTY_FUNCTION__ )) | |||
10237 | "fields within the closure type")(static_cast <bool> (NumFields == (size_t)std::distance (E->capture_init_begin(), E->capture_init_end()) && "The number of lambda capture initializers should equal the number of " "fields within the closure type") ? void (0) : __assert_fail ("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\"" , "clang/lib/AST/ExprConstant.cpp", 10237, __extension__ __PRETTY_FUNCTION__ )); | |||
10238 | ||||
10239 | Result = APValue(APValue::UninitStruct(), /*NumBases*/0, NumFields); | |||
10240 | // Iterate through all the lambda's closure object's fields and initialize | |||
10241 | // them. | |||
10242 | auto *CaptureInitIt = E->capture_init_begin(); | |||
10243 | bool Success = true; | |||
10244 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(ClosureClass); | |||
10245 | for (const auto *Field : ClosureClass->fields()) { | |||
10246 | assert(CaptureInitIt != E->capture_init_end())(static_cast <bool> (CaptureInitIt != E->capture_init_end ()) ? void (0) : __assert_fail ("CaptureInitIt != E->capture_init_end()" , "clang/lib/AST/ExprConstant.cpp", 10246, __extension__ __PRETTY_FUNCTION__ )); | |||
10247 | // Get the initializer for this field | |||
10248 | Expr *const CurFieldInit = *CaptureInitIt++; | |||
10249 | ||||
10250 | // If there is no initializer, either this is a VLA or an error has | |||
10251 | // occurred. | |||
10252 | if (!CurFieldInit) | |||
10253 | return Error(E); | |||
10254 | ||||
10255 | LValue Subobject = This; | |||
10256 | ||||
10257 | if (!HandleLValueMember(Info, E, Subobject, Field, &Layout)) | |||
10258 | return false; | |||
10259 | ||||
10260 | APValue &FieldVal = Result.getStructField(Field->getFieldIndex()); | |||
10261 | if (!EvaluateInPlace(FieldVal, Info, Subobject, CurFieldInit)) { | |||
10262 | if (!Info.keepEvaluatingAfterFailure()) | |||
10263 | return false; | |||
10264 | Success = false; | |||
10265 | } | |||
10266 | } | |||
10267 | return Success; | |||
10268 | } | |||
10269 | ||||
10270 | static bool EvaluateRecord(const Expr *E, const LValue &This, | |||
10271 | APValue &Result, EvalInfo &Info) { | |||
10272 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 10272, __extension__ __PRETTY_FUNCTION__)); | |||
10273 | assert(E->isPRValue() && E->getType()->isRecordType() &&(static_cast <bool> (E->isPRValue() && E-> getType()->isRecordType() && "can't evaluate expression as a record rvalue" ) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isRecordType() && \"can't evaluate expression as a record rvalue\"" , "clang/lib/AST/ExprConstant.cpp", 10274, __extension__ __PRETTY_FUNCTION__ )) | |||
10274 | "can't evaluate expression as a record rvalue")(static_cast <bool> (E->isPRValue() && E-> getType()->isRecordType() && "can't evaluate expression as a record rvalue" ) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isRecordType() && \"can't evaluate expression as a record rvalue\"" , "clang/lib/AST/ExprConstant.cpp", 10274, __extension__ __PRETTY_FUNCTION__ )); | |||
10275 | return RecordExprEvaluator(Info, This, Result).Visit(E); | |||
10276 | } | |||
10277 | ||||
10278 | //===----------------------------------------------------------------------===// | |||
10279 | // Temporary Evaluation | |||
10280 | // | |||
10281 | // Temporaries are represented in the AST as rvalues, but generally behave like | |||
10282 | // lvalues. The full-object of which the temporary is a subobject is implicitly | |||
10283 | // materialized so that a reference can bind to it. | |||
10284 | //===----------------------------------------------------------------------===// | |||
10285 | namespace { | |||
10286 | class TemporaryExprEvaluator | |||
10287 | : public LValueExprEvaluatorBase<TemporaryExprEvaluator> { | |||
10288 | public: | |||
10289 | TemporaryExprEvaluator(EvalInfo &Info, LValue &Result) : | |||
10290 | LValueExprEvaluatorBaseTy(Info, Result, false) {} | |||
10291 | ||||
10292 | /// Visit an expression which constructs the value of this temporary. | |||
10293 | bool VisitConstructExpr(const Expr *E) { | |||
10294 | APValue &Value = Info.CurrentCall->createTemporary( | |||
10295 | E, E->getType(), ScopeKind::FullExpression, Result); | |||
10296 | return EvaluateInPlace(Value, Info, Result, E); | |||
10297 | } | |||
10298 | ||||
10299 | bool VisitCastExpr(const CastExpr *E) { | |||
10300 | switch (E->getCastKind()) { | |||
10301 | default: | |||
10302 | return LValueExprEvaluatorBaseTy::VisitCastExpr(E); | |||
10303 | ||||
10304 | case CK_ConstructorConversion: | |||
10305 | return VisitConstructExpr(E->getSubExpr()); | |||
10306 | } | |||
10307 | } | |||
10308 | bool VisitInitListExpr(const InitListExpr *E) { | |||
10309 | return VisitConstructExpr(E); | |||
10310 | } | |||
10311 | bool VisitCXXConstructExpr(const CXXConstructExpr *E) { | |||
10312 | return VisitConstructExpr(E); | |||
10313 | } | |||
10314 | bool VisitCallExpr(const CallExpr *E) { | |||
10315 | return VisitConstructExpr(E); | |||
10316 | } | |||
10317 | bool VisitCXXStdInitializerListExpr(const CXXStdInitializerListExpr *E) { | |||
10318 | return VisitConstructExpr(E); | |||
10319 | } | |||
10320 | bool VisitLambdaExpr(const LambdaExpr *E) { | |||
10321 | return VisitConstructExpr(E); | |||
10322 | } | |||
10323 | }; | |||
10324 | } // end anonymous namespace | |||
10325 | ||||
10326 | /// Evaluate an expression of record type as a temporary. | |||
10327 | static bool EvaluateTemporary(const Expr *E, LValue &Result, EvalInfo &Info) { | |||
10328 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 10328, __extension__ __PRETTY_FUNCTION__)); | |||
10329 | assert(E->isPRValue() && E->getType()->isRecordType())(static_cast <bool> (E->isPRValue() && E-> getType()->isRecordType()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isRecordType()" , "clang/lib/AST/ExprConstant.cpp", 10329, __extension__ __PRETTY_FUNCTION__ )); | |||
10330 | return TemporaryExprEvaluator(Info, Result).Visit(E); | |||
10331 | } | |||
10332 | ||||
10333 | //===----------------------------------------------------------------------===// | |||
10334 | // Vector Evaluation | |||
10335 | //===----------------------------------------------------------------------===// | |||
10336 | ||||
10337 | namespace { | |||
10338 | class VectorExprEvaluator | |||
10339 | : public ExprEvaluatorBase<VectorExprEvaluator> { | |||
10340 | APValue &Result; | |||
10341 | public: | |||
10342 | ||||
10343 | VectorExprEvaluator(EvalInfo &info, APValue &Result) | |||
10344 | : ExprEvaluatorBaseTy(info), Result(Result) {} | |||
10345 | ||||
10346 | bool Success(ArrayRef<APValue> V, const Expr *E) { | |||
10347 | assert(V.size() == E->getType()->castAs<VectorType>()->getNumElements())(static_cast <bool> (V.size() == E->getType()->castAs <VectorType>()->getNumElements()) ? void (0) : __assert_fail ("V.size() == E->getType()->castAs<VectorType>()->getNumElements()" , "clang/lib/AST/ExprConstant.cpp", 10347, __extension__ __PRETTY_FUNCTION__ )); | |||
10348 | // FIXME: remove this APValue copy. | |||
10349 | Result = APValue(V.data(), V.size()); | |||
10350 | return true; | |||
10351 | } | |||
10352 | bool Success(const APValue &V, const Expr *E) { | |||
10353 | assert(V.isVector())(static_cast <bool> (V.isVector()) ? void (0) : __assert_fail ("V.isVector()", "clang/lib/AST/ExprConstant.cpp", 10353, __extension__ __PRETTY_FUNCTION__)); | |||
10354 | Result = V; | |||
10355 | return true; | |||
10356 | } | |||
10357 | bool ZeroInitialization(const Expr *E); | |||
10358 | ||||
10359 | bool VisitUnaryReal(const UnaryOperator *E) | |||
10360 | { return Visit(E->getSubExpr()); } | |||
10361 | bool VisitCastExpr(const CastExpr* E); | |||
10362 | bool VisitInitListExpr(const InitListExpr *E); | |||
10363 | bool VisitUnaryImag(const UnaryOperator *E); | |||
10364 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
10365 | bool VisitUnaryOperator(const UnaryOperator *E); | |||
10366 | // FIXME: Missing: conditional operator (for GNU | |||
10367 | // conditional select), shufflevector, ExtVectorElementExpr | |||
10368 | }; | |||
10369 | } // end anonymous namespace | |||
10370 | ||||
10371 | static bool EvaluateVector(const Expr* E, APValue& Result, EvalInfo &Info) { | |||
10372 | assert(E->isPRValue() && E->getType()->isVectorType() &&(static_cast <bool> (E->isPRValue() && E-> getType()->isVectorType() && "not a vector prvalue" ) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isVectorType() && \"not a vector prvalue\"" , "clang/lib/AST/ExprConstant.cpp", 10373, __extension__ __PRETTY_FUNCTION__ )) | |||
10373 | "not a vector prvalue")(static_cast <bool> (E->isPRValue() && E-> getType()->isVectorType() && "not a vector prvalue" ) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isVectorType() && \"not a vector prvalue\"" , "clang/lib/AST/ExprConstant.cpp", 10373, __extension__ __PRETTY_FUNCTION__ )); | |||
10374 | return VectorExprEvaluator(Info, Result).Visit(E); | |||
10375 | } | |||
10376 | ||||
10377 | bool VectorExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
10378 | const VectorType *VTy = E->getType()->castAs<VectorType>(); | |||
10379 | unsigned NElts = VTy->getNumElements(); | |||
10380 | ||||
10381 | const Expr *SE = E->getSubExpr(); | |||
10382 | QualType SETy = SE->getType(); | |||
10383 | ||||
10384 | switch (E->getCastKind()) { | |||
10385 | case CK_VectorSplat: { | |||
10386 | APValue Val = APValue(); | |||
10387 | if (SETy->isIntegerType()) { | |||
10388 | APSInt IntResult; | |||
10389 | if (!EvaluateInteger(SE, IntResult, Info)) | |||
10390 | return false; | |||
10391 | Val = APValue(std::move(IntResult)); | |||
10392 | } else if (SETy->isRealFloatingType()) { | |||
10393 | APFloat FloatResult(0.0); | |||
10394 | if (!EvaluateFloat(SE, FloatResult, Info)) | |||
10395 | return false; | |||
10396 | Val = APValue(std::move(FloatResult)); | |||
10397 | } else { | |||
10398 | return Error(E); | |||
10399 | } | |||
10400 | ||||
10401 | // Splat and create vector APValue. | |||
10402 | SmallVector<APValue, 4> Elts(NElts, Val); | |||
10403 | return Success(Elts, E); | |||
10404 | } | |||
10405 | case CK_BitCast: { | |||
10406 | // Evaluate the operand into an APInt we can extract from. | |||
10407 | llvm::APInt SValInt; | |||
10408 | if (!EvalAndBitcastToAPInt(Info, SE, SValInt)) | |||
10409 | return false; | |||
10410 | // Extract the elements | |||
10411 | QualType EltTy = VTy->getElementType(); | |||
10412 | unsigned EltSize = Info.Ctx.getTypeSize(EltTy); | |||
10413 | bool BigEndian = Info.Ctx.getTargetInfo().isBigEndian(); | |||
10414 | SmallVector<APValue, 4> Elts; | |||
10415 | if (EltTy->isRealFloatingType()) { | |||
10416 | const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(EltTy); | |||
10417 | unsigned FloatEltSize = EltSize; | |||
10418 | if (&Sem == &APFloat::x87DoubleExtended()) | |||
10419 | FloatEltSize = 80; | |||
10420 | for (unsigned i = 0; i < NElts; i++) { | |||
10421 | llvm::APInt Elt; | |||
10422 | if (BigEndian) | |||
10423 | Elt = SValInt.rotl(i * EltSize + FloatEltSize).trunc(FloatEltSize); | |||
10424 | else | |||
10425 | Elt = SValInt.rotr(i * EltSize).trunc(FloatEltSize); | |||
10426 | Elts.push_back(APValue(APFloat(Sem, Elt))); | |||
10427 | } | |||
10428 | } else if (EltTy->isIntegerType()) { | |||
10429 | for (unsigned i = 0; i < NElts; i++) { | |||
10430 | llvm::APInt Elt; | |||
10431 | if (BigEndian) | |||
10432 | Elt = SValInt.rotl(i*EltSize+EltSize).zextOrTrunc(EltSize); | |||
10433 | else | |||
10434 | Elt = SValInt.rotr(i*EltSize).zextOrTrunc(EltSize); | |||
10435 | Elts.push_back(APValue(APSInt(Elt, !EltTy->isSignedIntegerType()))); | |||
10436 | } | |||
10437 | } else { | |||
10438 | return Error(E); | |||
10439 | } | |||
10440 | return Success(Elts, E); | |||
10441 | } | |||
10442 | default: | |||
10443 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
10444 | } | |||
10445 | } | |||
10446 | ||||
10447 | bool | |||
10448 | VectorExprEvaluator::VisitInitListExpr(const InitListExpr *E) { | |||
10449 | const VectorType *VT = E->getType()->castAs<VectorType>(); | |||
10450 | unsigned NumInits = E->getNumInits(); | |||
10451 | unsigned NumElements = VT->getNumElements(); | |||
10452 | ||||
10453 | QualType EltTy = VT->getElementType(); | |||
10454 | SmallVector<APValue, 4> Elements; | |||
10455 | ||||
10456 | // The number of initializers can be less than the number of | |||
10457 | // vector elements. For OpenCL, this can be due to nested vector | |||
10458 | // initialization. For GCC compatibility, missing trailing elements | |||
10459 | // should be initialized with zeroes. | |||
10460 | unsigned CountInits = 0, CountElts = 0; | |||
10461 | while (CountElts < NumElements) { | |||
10462 | // Handle nested vector initialization. | |||
10463 | if (CountInits < NumInits | |||
10464 | && E->getInit(CountInits)->getType()->isVectorType()) { | |||
10465 | APValue v; | |||
10466 | if (!EvaluateVector(E->getInit(CountInits), v, Info)) | |||
10467 | return Error(E); | |||
10468 | unsigned vlen = v.getVectorLength(); | |||
10469 | for (unsigned j = 0; j < vlen; j++) | |||
10470 | Elements.push_back(v.getVectorElt(j)); | |||
10471 | CountElts += vlen; | |||
10472 | } else if (EltTy->isIntegerType()) { | |||
10473 | llvm::APSInt sInt(32); | |||
10474 | if (CountInits < NumInits) { | |||
10475 | if (!EvaluateInteger(E->getInit(CountInits), sInt, Info)) | |||
10476 | return false; | |||
10477 | } else // trailing integer zero. | |||
10478 | sInt = Info.Ctx.MakeIntValue(0, EltTy); | |||
10479 | Elements.push_back(APValue(sInt)); | |||
10480 | CountElts++; | |||
10481 | } else { | |||
10482 | llvm::APFloat f(0.0); | |||
10483 | if (CountInits < NumInits) { | |||
10484 | if (!EvaluateFloat(E->getInit(CountInits), f, Info)) | |||
10485 | return false; | |||
10486 | } else // trailing float zero. | |||
10487 | f = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy)); | |||
10488 | Elements.push_back(APValue(f)); | |||
10489 | CountElts++; | |||
10490 | } | |||
10491 | CountInits++; | |||
10492 | } | |||
10493 | return Success(Elements, E); | |||
10494 | } | |||
10495 | ||||
10496 | bool | |||
10497 | VectorExprEvaluator::ZeroInitialization(const Expr *E) { | |||
10498 | const auto *VT = E->getType()->castAs<VectorType>(); | |||
10499 | QualType EltTy = VT->getElementType(); | |||
10500 | APValue ZeroElement; | |||
10501 | if (EltTy->isIntegerType()) | |||
10502 | ZeroElement = APValue(Info.Ctx.MakeIntValue(0, EltTy)); | |||
10503 | else | |||
10504 | ZeroElement = | |||
10505 | APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy))); | |||
10506 | ||||
10507 | SmallVector<APValue, 4> Elements(VT->getNumElements(), ZeroElement); | |||
10508 | return Success(Elements, E); | |||
10509 | } | |||
10510 | ||||
10511 | bool VectorExprEvaluator::VisitUnaryImag(const UnaryOperator *E) { | |||
10512 | VisitIgnoredValue(E->getSubExpr()); | |||
10513 | return ZeroInitialization(E); | |||
10514 | } | |||
10515 | ||||
10516 | bool VectorExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
10517 | BinaryOperatorKind Op = E->getOpcode(); | |||
10518 | assert(Op != BO_PtrMemD && Op != BO_PtrMemI && Op != BO_Cmp &&(static_cast <bool> (Op != BO_PtrMemD && Op != BO_PtrMemI && Op != BO_Cmp && "Operation not supported on vector types" ) ? void (0) : __assert_fail ("Op != BO_PtrMemD && Op != BO_PtrMemI && Op != BO_Cmp && \"Operation not supported on vector types\"" , "clang/lib/AST/ExprConstant.cpp", 10519, __extension__ __PRETTY_FUNCTION__ )) | |||
10519 | "Operation not supported on vector types")(static_cast <bool> (Op != BO_PtrMemD && Op != BO_PtrMemI && Op != BO_Cmp && "Operation not supported on vector types" ) ? void (0) : __assert_fail ("Op != BO_PtrMemD && Op != BO_PtrMemI && Op != BO_Cmp && \"Operation not supported on vector types\"" , "clang/lib/AST/ExprConstant.cpp", 10519, __extension__ __PRETTY_FUNCTION__ )); | |||
10520 | ||||
10521 | if (Op == BO_Comma) | |||
10522 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
10523 | ||||
10524 | Expr *LHS = E->getLHS(); | |||
10525 | Expr *RHS = E->getRHS(); | |||
10526 | ||||
10527 | assert(LHS->getType()->isVectorType() && RHS->getType()->isVectorType() &&(static_cast <bool> (LHS->getType()->isVectorType () && RHS->getType()->isVectorType() && "Must both be vector types") ? void (0) : __assert_fail ("LHS->getType()->isVectorType() && RHS->getType()->isVectorType() && \"Must both be vector types\"" , "clang/lib/AST/ExprConstant.cpp", 10528, __extension__ __PRETTY_FUNCTION__ )) | |||
10528 | "Must both be vector types")(static_cast <bool> (LHS->getType()->isVectorType () && RHS->getType()->isVectorType() && "Must both be vector types") ? void (0) : __assert_fail ("LHS->getType()->isVectorType() && RHS->getType()->isVectorType() && \"Must both be vector types\"" , "clang/lib/AST/ExprConstant.cpp", 10528, __extension__ __PRETTY_FUNCTION__ )); | |||
10529 | // Checking JUST the types are the same would be fine, except shifts don't | |||
10530 | // need to have their types be the same (since you always shift by an int). | |||
10531 | assert(LHS->getType()->castAs<VectorType>()->getNumElements() ==(static_cast <bool> (LHS->getType()->castAs<VectorType >()->getNumElements() == E->getType()->castAs< VectorType>()->getNumElements() && RHS->getType ()->castAs<VectorType>()->getNumElements() == E-> getType()->castAs<VectorType>()->getNumElements() && "All operands must be the same size.") ? void (0) : __assert_fail ("LHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && RHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && \"All operands must be the same size.\"" , "clang/lib/AST/ExprConstant.cpp", 10535, __extension__ __PRETTY_FUNCTION__ )) | |||
10532 | E->getType()->castAs<VectorType>()->getNumElements() &&(static_cast <bool> (LHS->getType()->castAs<VectorType >()->getNumElements() == E->getType()->castAs< VectorType>()->getNumElements() && RHS->getType ()->castAs<VectorType>()->getNumElements() == E-> getType()->castAs<VectorType>()->getNumElements() && "All operands must be the same size.") ? void (0) : __assert_fail ("LHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && RHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && \"All operands must be the same size.\"" , "clang/lib/AST/ExprConstant.cpp", 10535, __extension__ __PRETTY_FUNCTION__ )) | |||
10533 | RHS->getType()->castAs<VectorType>()->getNumElements() ==(static_cast <bool> (LHS->getType()->castAs<VectorType >()->getNumElements() == E->getType()->castAs< VectorType>()->getNumElements() && RHS->getType ()->castAs<VectorType>()->getNumElements() == E-> getType()->castAs<VectorType>()->getNumElements() && "All operands must be the same size.") ? void (0) : __assert_fail ("LHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && RHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && \"All operands must be the same size.\"" , "clang/lib/AST/ExprConstant.cpp", 10535, __extension__ __PRETTY_FUNCTION__ )) | |||
10534 | E->getType()->castAs<VectorType>()->getNumElements() &&(static_cast <bool> (LHS->getType()->castAs<VectorType >()->getNumElements() == E->getType()->castAs< VectorType>()->getNumElements() && RHS->getType ()->castAs<VectorType>()->getNumElements() == E-> getType()->castAs<VectorType>()->getNumElements() && "All operands must be the same size.") ? void (0) : __assert_fail ("LHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && RHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && \"All operands must be the same size.\"" , "clang/lib/AST/ExprConstant.cpp", 10535, __extension__ __PRETTY_FUNCTION__ )) | |||
10535 | "All operands must be the same size.")(static_cast <bool> (LHS->getType()->castAs<VectorType >()->getNumElements() == E->getType()->castAs< VectorType>()->getNumElements() && RHS->getType ()->castAs<VectorType>()->getNumElements() == E-> getType()->castAs<VectorType>()->getNumElements() && "All operands must be the same size.") ? void (0) : __assert_fail ("LHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && RHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && \"All operands must be the same size.\"" , "clang/lib/AST/ExprConstant.cpp", 10535, __extension__ __PRETTY_FUNCTION__ )); | |||
10536 | ||||
10537 | APValue LHSValue; | |||
10538 | APValue RHSValue; | |||
10539 | bool LHSOK = Evaluate(LHSValue, Info, LHS); | |||
10540 | if (!LHSOK && !Info.noteFailure()) | |||
10541 | return false; | |||
10542 | if (!Evaluate(RHSValue, Info, RHS) || !LHSOK) | |||
10543 | return false; | |||
10544 | ||||
10545 | if (!handleVectorVectorBinOp(Info, E, Op, LHSValue, RHSValue)) | |||
10546 | return false; | |||
10547 | ||||
10548 | return Success(LHSValue, E); | |||
10549 | } | |||
10550 | ||||
10551 | static std::optional<APValue> handleVectorUnaryOperator(ASTContext &Ctx, | |||
10552 | QualType ResultTy, | |||
10553 | UnaryOperatorKind Op, | |||
10554 | APValue Elt) { | |||
10555 | switch (Op) { | |||
10556 | case UO_Plus: | |||
10557 | // Nothing to do here. | |||
10558 | return Elt; | |||
10559 | case UO_Minus: | |||
10560 | if (Elt.getKind() == APValue::Int) { | |||
10561 | Elt.getInt().negate(); | |||
10562 | } else { | |||
10563 | assert(Elt.getKind() == APValue::Float &&(static_cast <bool> (Elt.getKind() == APValue::Float && "Vector can only be int or float type") ? void (0) : __assert_fail ("Elt.getKind() == APValue::Float && \"Vector can only be int or float type\"" , "clang/lib/AST/ExprConstant.cpp", 10564, __extension__ __PRETTY_FUNCTION__ )) | |||
10564 | "Vector can only be int or float type")(static_cast <bool> (Elt.getKind() == APValue::Float && "Vector can only be int or float type") ? void (0) : __assert_fail ("Elt.getKind() == APValue::Float && \"Vector can only be int or float type\"" , "clang/lib/AST/ExprConstant.cpp", 10564, __extension__ __PRETTY_FUNCTION__ )); | |||
10565 | Elt.getFloat().changeSign(); | |||
10566 | } | |||
10567 | return Elt; | |||
10568 | case UO_Not: | |||
10569 | // This is only valid for integral types anyway, so we don't have to handle | |||
10570 | // float here. | |||
10571 | assert(Elt.getKind() == APValue::Int &&(static_cast <bool> (Elt.getKind() == APValue::Int && "Vector operator ~ can only be int") ? void (0) : __assert_fail ("Elt.getKind() == APValue::Int && \"Vector operator ~ can only be int\"" , "clang/lib/AST/ExprConstant.cpp", 10572, __extension__ __PRETTY_FUNCTION__ )) | |||
10572 | "Vector operator ~ can only be int")(static_cast <bool> (Elt.getKind() == APValue::Int && "Vector operator ~ can only be int") ? void (0) : __assert_fail ("Elt.getKind() == APValue::Int && \"Vector operator ~ can only be int\"" , "clang/lib/AST/ExprConstant.cpp", 10572, __extension__ __PRETTY_FUNCTION__ )); | |||
10573 | Elt.getInt().flipAllBits(); | |||
10574 | return Elt; | |||
10575 | case UO_LNot: { | |||
10576 | if (Elt.getKind() == APValue::Int) { | |||
10577 | Elt.getInt() = !Elt.getInt(); | |||
10578 | // operator ! on vectors returns -1 for 'truth', so negate it. | |||
10579 | Elt.getInt().negate(); | |||
10580 | return Elt; | |||
10581 | } | |||
10582 | assert(Elt.getKind() == APValue::Float &&(static_cast <bool> (Elt.getKind() == APValue::Float && "Vector can only be int or float type") ? void (0) : __assert_fail ("Elt.getKind() == APValue::Float && \"Vector can only be int or float type\"" , "clang/lib/AST/ExprConstant.cpp", 10583, __extension__ __PRETTY_FUNCTION__ )) | |||
10583 | "Vector can only be int or float type")(static_cast <bool> (Elt.getKind() == APValue::Float && "Vector can only be int or float type") ? void (0) : __assert_fail ("Elt.getKind() == APValue::Float && \"Vector can only be int or float type\"" , "clang/lib/AST/ExprConstant.cpp", 10583, __extension__ __PRETTY_FUNCTION__ )); | |||
10584 | // Float types result in an int of the same size, but -1 for true, or 0 for | |||
10585 | // false. | |||
10586 | APSInt EltResult{Ctx.getIntWidth(ResultTy), | |||
10587 | ResultTy->isUnsignedIntegerType()}; | |||
10588 | if (Elt.getFloat().isZero()) | |||
10589 | EltResult.setAllBits(); | |||
10590 | else | |||
10591 | EltResult.clearAllBits(); | |||
10592 | ||||
10593 | return APValue{EltResult}; | |||
10594 | } | |||
10595 | default: | |||
10596 | // FIXME: Implement the rest of the unary operators. | |||
10597 | return std::nullopt; | |||
10598 | } | |||
10599 | } | |||
10600 | ||||
10601 | bool VectorExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { | |||
10602 | Expr *SubExpr = E->getSubExpr(); | |||
10603 | const auto *VD = SubExpr->getType()->castAs<VectorType>(); | |||
10604 | // This result element type differs in the case of negating a floating point | |||
10605 | // vector, since the result type is the a vector of the equivilant sized | |||
10606 | // integer. | |||
10607 | const QualType ResultEltTy = VD->getElementType(); | |||
10608 | UnaryOperatorKind Op = E->getOpcode(); | |||
10609 | ||||
10610 | APValue SubExprValue; | |||
10611 | if (!Evaluate(SubExprValue, Info, SubExpr)) | |||
10612 | return false; | |||
10613 | ||||
10614 | // FIXME: This vector evaluator someday needs to be changed to be LValue | |||
10615 | // aware/keep LValue information around, rather than dealing with just vector | |||
10616 | // types directly. Until then, we cannot handle cases where the operand to | |||
10617 | // these unary operators is an LValue. The only case I've been able to see | |||
10618 | // cause this is operator++ assigning to a member expression (only valid in | |||
10619 | // altivec compilations) in C mode, so this shouldn't limit us too much. | |||
10620 | if (SubExprValue.isLValue()) | |||
10621 | return false; | |||
10622 | ||||
10623 | assert(SubExprValue.getVectorLength() == VD->getNumElements() &&(static_cast <bool> (SubExprValue.getVectorLength() == VD ->getNumElements() && "Vector length doesn't match type?" ) ? void (0) : __assert_fail ("SubExprValue.getVectorLength() == VD->getNumElements() && \"Vector length doesn't match type?\"" , "clang/lib/AST/ExprConstant.cpp", 10624, __extension__ __PRETTY_FUNCTION__ )) | |||
10624 | "Vector length doesn't match type?")(static_cast <bool> (SubExprValue.getVectorLength() == VD ->getNumElements() && "Vector length doesn't match type?" ) ? void (0) : __assert_fail ("SubExprValue.getVectorLength() == VD->getNumElements() && \"Vector length doesn't match type?\"" , "clang/lib/AST/ExprConstant.cpp", 10624, __extension__ __PRETTY_FUNCTION__ )); | |||
10625 | ||||
10626 | SmallVector<APValue, 4> ResultElements; | |||
10627 | for (unsigned EltNum = 0; EltNum < VD->getNumElements(); ++EltNum) { | |||
10628 | std::optional<APValue> Elt = handleVectorUnaryOperator( | |||
10629 | Info.Ctx, ResultEltTy, Op, SubExprValue.getVectorElt(EltNum)); | |||
10630 | if (!Elt) | |||
10631 | return false; | |||
10632 | ResultElements.push_back(*Elt); | |||
10633 | } | |||
10634 | return Success(APValue(ResultElements.data(), ResultElements.size()), E); | |||
10635 | } | |||
10636 | ||||
10637 | //===----------------------------------------------------------------------===// | |||
10638 | // Array Evaluation | |||
10639 | //===----------------------------------------------------------------------===// | |||
10640 | ||||
10641 | namespace { | |||
10642 | class ArrayExprEvaluator | |||
10643 | : public ExprEvaluatorBase<ArrayExprEvaluator> { | |||
10644 | const LValue &This; | |||
10645 | APValue &Result; | |||
10646 | public: | |||
10647 | ||||
10648 | ArrayExprEvaluator(EvalInfo &Info, const LValue &This, APValue &Result) | |||
10649 | : ExprEvaluatorBaseTy(Info), This(This), Result(Result) {} | |||
10650 | ||||
10651 | bool Success(const APValue &V, const Expr *E) { | |||
10652 | assert(V.isArray() && "expected array")(static_cast <bool> (V.isArray() && "expected array" ) ? void (0) : __assert_fail ("V.isArray() && \"expected array\"" , "clang/lib/AST/ExprConstant.cpp", 10652, __extension__ __PRETTY_FUNCTION__ )); | |||
10653 | Result = V; | |||
10654 | return true; | |||
10655 | } | |||
10656 | ||||
10657 | bool ZeroInitialization(const Expr *E) { | |||
10658 | const ConstantArrayType *CAT = | |||
10659 | Info.Ctx.getAsConstantArrayType(E->getType()); | |||
10660 | if (!CAT) { | |||
10661 | if (E->getType()->isIncompleteArrayType()) { | |||
10662 | // We can be asked to zero-initialize a flexible array member; this | |||
10663 | // is represented as an ImplicitValueInitExpr of incomplete array | |||
10664 | // type. In this case, the array has zero elements. | |||
10665 | Result = APValue(APValue::UninitArray(), 0, 0); | |||
10666 | return true; | |||
10667 | } | |||
10668 | // FIXME: We could handle VLAs here. | |||
10669 | return Error(E); | |||
10670 | } | |||
10671 | ||||
10672 | Result = APValue(APValue::UninitArray(), 0, | |||
10673 | CAT->getSize().getZExtValue()); | |||
10674 | if (!Result.hasArrayFiller()) | |||
10675 | return true; | |||
10676 | ||||
10677 | // Zero-initialize all elements. | |||
10678 | LValue Subobject = This; | |||
10679 | Subobject.addArray(Info, E, CAT); | |||
10680 | ImplicitValueInitExpr VIE(CAT->getElementType()); | |||
10681 | return EvaluateInPlace(Result.getArrayFiller(), Info, Subobject, &VIE); | |||
10682 | } | |||
10683 | ||||
10684 | bool VisitCallExpr(const CallExpr *E) { | |||
10685 | return handleCallExpr(E, Result, &This); | |||
10686 | } | |||
10687 | bool VisitInitListExpr(const InitListExpr *E, | |||
10688 | QualType AllocType = QualType()); | |||
10689 | bool VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E); | |||
10690 | bool VisitCXXConstructExpr(const CXXConstructExpr *E); | |||
10691 | bool VisitCXXConstructExpr(const CXXConstructExpr *E, | |||
10692 | const LValue &Subobject, | |||
10693 | APValue *Value, QualType Type); | |||
10694 | bool VisitStringLiteral(const StringLiteral *E, | |||
10695 | QualType AllocType = QualType()) { | |||
10696 | expandStringLiteral(Info, E, Result, AllocType); | |||
10697 | return true; | |||
10698 | } | |||
10699 | bool VisitCXXParenListInitExpr(const CXXParenListInitExpr *E); | |||
10700 | bool VisitCXXParenListOrInitListExpr(const Expr *ExprToVisit, | |||
10701 | ArrayRef<Expr *> Args, | |||
10702 | const Expr *ArrayFiller, | |||
10703 | QualType AllocType = QualType()); | |||
10704 | }; | |||
10705 | } // end anonymous namespace | |||
10706 | ||||
10707 | static bool EvaluateArray(const Expr *E, const LValue &This, | |||
10708 | APValue &Result, EvalInfo &Info) { | |||
10709 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 10709, __extension__ __PRETTY_FUNCTION__)); | |||
10710 | assert(E->isPRValue() && E->getType()->isArrayType() &&(static_cast <bool> (E->isPRValue() && E-> getType()->isArrayType() && "not an array prvalue" ) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isArrayType() && \"not an array prvalue\"" , "clang/lib/AST/ExprConstant.cpp", 10711, __extension__ __PRETTY_FUNCTION__ )) | |||
10711 | "not an array prvalue")(static_cast <bool> (E->isPRValue() && E-> getType()->isArrayType() && "not an array prvalue" ) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isArrayType() && \"not an array prvalue\"" , "clang/lib/AST/ExprConstant.cpp", 10711, __extension__ __PRETTY_FUNCTION__ )); | |||
10712 | return ArrayExprEvaluator(Info, This, Result).Visit(E); | |||
10713 | } | |||
10714 | ||||
10715 | static bool EvaluateArrayNewInitList(EvalInfo &Info, LValue &This, | |||
10716 | APValue &Result, const InitListExpr *ILE, | |||
10717 | QualType AllocType) { | |||
10718 | assert(!ILE->isValueDependent())(static_cast <bool> (!ILE->isValueDependent()) ? void (0) : __assert_fail ("!ILE->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 10718, __extension__ __PRETTY_FUNCTION__)); | |||
10719 | assert(ILE->isPRValue() && ILE->getType()->isArrayType() &&(static_cast <bool> (ILE->isPRValue() && ILE ->getType()->isArrayType() && "not an array prvalue" ) ? void (0) : __assert_fail ("ILE->isPRValue() && ILE->getType()->isArrayType() && \"not an array prvalue\"" , "clang/lib/AST/ExprConstant.cpp", 10720, __extension__ __PRETTY_FUNCTION__ )) | |||
10720 | "not an array prvalue")(static_cast <bool> (ILE->isPRValue() && ILE ->getType()->isArrayType() && "not an array prvalue" ) ? void (0) : __assert_fail ("ILE->isPRValue() && ILE->getType()->isArrayType() && \"not an array prvalue\"" , "clang/lib/AST/ExprConstant.cpp", 10720, __extension__ __PRETTY_FUNCTION__ )); | |||
10721 | return ArrayExprEvaluator(Info, This, Result) | |||
10722 | .VisitInitListExpr(ILE, AllocType); | |||
10723 | } | |||
10724 | ||||
10725 | static bool EvaluateArrayNewConstructExpr(EvalInfo &Info, LValue &This, | |||
10726 | APValue &Result, | |||
10727 | const CXXConstructExpr *CCE, | |||
10728 | QualType AllocType) { | |||
10729 | assert(!CCE->isValueDependent())(static_cast <bool> (!CCE->isValueDependent()) ? void (0) : __assert_fail ("!CCE->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 10729, __extension__ __PRETTY_FUNCTION__)); | |||
10730 | assert(CCE->isPRValue() && CCE->getType()->isArrayType() &&(static_cast <bool> (CCE->isPRValue() && CCE ->getType()->isArrayType() && "not an array prvalue" ) ? void (0) : __assert_fail ("CCE->isPRValue() && CCE->getType()->isArrayType() && \"not an array prvalue\"" , "clang/lib/AST/ExprConstant.cpp", 10731, __extension__ __PRETTY_FUNCTION__ )) | |||
10731 | "not an array prvalue")(static_cast <bool> (CCE->isPRValue() && CCE ->getType()->isArrayType() && "not an array prvalue" ) ? void (0) : __assert_fail ("CCE->isPRValue() && CCE->getType()->isArrayType() && \"not an array prvalue\"" , "clang/lib/AST/ExprConstant.cpp", 10731, __extension__ __PRETTY_FUNCTION__ )); | |||
10732 | return ArrayExprEvaluator(Info, This, Result) | |||
10733 | .VisitCXXConstructExpr(CCE, This, &Result, AllocType); | |||
10734 | } | |||
10735 | ||||
10736 | // Return true iff the given array filler may depend on the element index. | |||
10737 | static bool MaybeElementDependentArrayFiller(const Expr *FillerExpr) { | |||
10738 | // For now, just allow non-class value-initialization and initialization | |||
10739 | // lists comprised of them. | |||
10740 | if (isa<ImplicitValueInitExpr>(FillerExpr)) | |||
10741 | return false; | |||
10742 | if (const InitListExpr *ILE = dyn_cast<InitListExpr>(FillerExpr)) { | |||
10743 | for (unsigned I = 0, E = ILE->getNumInits(); I != E; ++I) { | |||
10744 | if (MaybeElementDependentArrayFiller(ILE->getInit(I))) | |||
10745 | return true; | |||
10746 | } | |||
10747 | ||||
10748 | if (ILE->hasArrayFiller() && | |||
10749 | MaybeElementDependentArrayFiller(ILE->getArrayFiller())) | |||
10750 | return true; | |||
10751 | ||||
10752 | return false; | |||
10753 | } | |||
10754 | return true; | |||
10755 | } | |||
10756 | ||||
10757 | bool ArrayExprEvaluator::VisitInitListExpr(const InitListExpr *E, | |||
10758 | QualType AllocType) { | |||
10759 | const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType( | |||
10760 | AllocType.isNull() ? E->getType() : AllocType); | |||
10761 | if (!CAT) | |||
10762 | return Error(E); | |||
10763 | ||||
10764 | // C++11 [dcl.init.string]p1: A char array [...] can be initialized by [...] | |||
10765 | // an appropriately-typed string literal enclosed in braces. | |||
10766 | if (E->isStringLiteralInit()) { | |||
10767 | auto *SL = dyn_cast<StringLiteral>(E->getInit(0)->IgnoreParenImpCasts()); | |||
10768 | // FIXME: Support ObjCEncodeExpr here once we support it in | |||
10769 | // ArrayExprEvaluator generally. | |||
10770 | if (!SL) | |||
10771 | return Error(E); | |||
10772 | return VisitStringLiteral(SL, AllocType); | |||
10773 | } | |||
10774 | // Any other transparent list init will need proper handling of the | |||
10775 | // AllocType; we can't just recurse to the inner initializer. | |||
10776 | assert(!E->isTransparent() &&(static_cast <bool> (!E->isTransparent() && "transparent array list initialization is not string literal init?" ) ? void (0) : __assert_fail ("!E->isTransparent() && \"transparent array list initialization is not string literal init?\"" , "clang/lib/AST/ExprConstant.cpp", 10777, __extension__ __PRETTY_FUNCTION__ )) | |||
10777 | "transparent array list initialization is not string literal init?")(static_cast <bool> (!E->isTransparent() && "transparent array list initialization is not string literal init?" ) ? void (0) : __assert_fail ("!E->isTransparent() && \"transparent array list initialization is not string literal init?\"" , "clang/lib/AST/ExprConstant.cpp", 10777, __extension__ __PRETTY_FUNCTION__ )); | |||
10778 | ||||
10779 | return VisitCXXParenListOrInitListExpr(E, E->inits(), E->getArrayFiller(), | |||
10780 | AllocType); | |||
10781 | } | |||
10782 | ||||
10783 | bool ArrayExprEvaluator::VisitCXXParenListOrInitListExpr( | |||
10784 | const Expr *ExprToVisit, ArrayRef<Expr *> Args, const Expr *ArrayFiller, | |||
10785 | QualType AllocType) { | |||
10786 | const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType( | |||
10787 | AllocType.isNull() ? ExprToVisit->getType() : AllocType); | |||
10788 | ||||
10789 | bool Success = true; | |||
10790 | ||||
10791 | assert((!Result.isArray() || Result.getArrayInitializedElts() == 0) &&(static_cast <bool> ((!Result.isArray() || Result.getArrayInitializedElts () == 0) && "zero-initialized array shouldn't have any initialized elts" ) ? void (0) : __assert_fail ("(!Result.isArray() || Result.getArrayInitializedElts() == 0) && \"zero-initialized array shouldn't have any initialized elts\"" , "clang/lib/AST/ExprConstant.cpp", 10792, __extension__ __PRETTY_FUNCTION__ )) | |||
10792 | "zero-initialized array shouldn't have any initialized elts")(static_cast <bool> ((!Result.isArray() || Result.getArrayInitializedElts () == 0) && "zero-initialized array shouldn't have any initialized elts" ) ? void (0) : __assert_fail ("(!Result.isArray() || Result.getArrayInitializedElts() == 0) && \"zero-initialized array shouldn't have any initialized elts\"" , "clang/lib/AST/ExprConstant.cpp", 10792, __extension__ __PRETTY_FUNCTION__ )); | |||
10793 | APValue Filler; | |||
10794 | if (Result.isArray() && Result.hasArrayFiller()) | |||
10795 | Filler = Result.getArrayFiller(); | |||
10796 | ||||
10797 | unsigned NumEltsToInit = Args.size(); | |||
10798 | unsigned NumElts = CAT->getSize().getZExtValue(); | |||
10799 | ||||
10800 | // If the initializer might depend on the array index, run it for each | |||
10801 | // array element. | |||
10802 | if (NumEltsToInit != NumElts && MaybeElementDependentArrayFiller(ArrayFiller)) | |||
10803 | NumEltsToInit = NumElts; | |||
10804 | ||||
10805 | LLVM_DEBUG(llvm::dbgs() << "The number of elements to initialize: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("exprconstant")) { llvm::dbgs() << "The number of elements to initialize: " << NumEltsToInit << ".\n"; } } while (false) | |||
10806 | << NumEltsToInit << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("exprconstant")) { llvm::dbgs() << "The number of elements to initialize: " << NumEltsToInit << ".\n"; } } while (false); | |||
10807 | ||||
10808 | Result = APValue(APValue::UninitArray(), NumEltsToInit, NumElts); | |||
10809 | ||||
10810 | // If the array was previously zero-initialized, preserve the | |||
10811 | // zero-initialized values. | |||
10812 | if (Filler.hasValue()) { | |||
10813 | for (unsigned I = 0, E = Result.getArrayInitializedElts(); I != E; ++I) | |||
10814 | Result.getArrayInitializedElt(I) = Filler; | |||
10815 | if (Result.hasArrayFiller()) | |||
10816 | Result.getArrayFiller() = Filler; | |||
10817 | } | |||
10818 | ||||
10819 | LValue Subobject = This; | |||
10820 | Subobject.addArray(Info, ExprToVisit, CAT); | |||
10821 | for (unsigned Index = 0; Index != NumEltsToInit; ++Index) { | |||
10822 | const Expr *Init = Index < Args.size() ? Args[Index] : ArrayFiller; | |||
10823 | if (!EvaluateInPlace(Result.getArrayInitializedElt(Index), | |||
10824 | Info, Subobject, Init) || | |||
10825 | !HandleLValueArrayAdjustment(Info, Init, Subobject, | |||
10826 | CAT->getElementType(), 1)) { | |||
10827 | if (!Info.noteFailure()) | |||
10828 | return false; | |||
10829 | Success = false; | |||
10830 | } | |||
10831 | } | |||
10832 | ||||
10833 | if (!Result.hasArrayFiller()) | |||
10834 | return Success; | |||
10835 | ||||
10836 | // If we get here, we have a trivial filler, which we can just evaluate | |||
10837 | // once and splat over the rest of the array elements. | |||
10838 | assert(ArrayFiller && "no array filler for incomplete init list")(static_cast <bool> (ArrayFiller && "no array filler for incomplete init list" ) ? void (0) : __assert_fail ("ArrayFiller && \"no array filler for incomplete init list\"" , "clang/lib/AST/ExprConstant.cpp", 10838, __extension__ __PRETTY_FUNCTION__ )); | |||
10839 | return EvaluateInPlace(Result.getArrayFiller(), Info, Subobject, | |||
10840 | ArrayFiller) && | |||
10841 | Success; | |||
10842 | } | |||
10843 | ||||
10844 | bool ArrayExprEvaluator::VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E) { | |||
10845 | LValue CommonLV; | |||
10846 | if (E->getCommonExpr() && | |||
10847 | !Evaluate(Info.CurrentCall->createTemporary( | |||
10848 | E->getCommonExpr(), | |||
10849 | getStorageType(Info.Ctx, E->getCommonExpr()), | |||
10850 | ScopeKind::FullExpression, CommonLV), | |||
10851 | Info, E->getCommonExpr()->getSourceExpr())) | |||
10852 | return false; | |||
10853 | ||||
10854 | auto *CAT = cast<ConstantArrayType>(E->getType()->castAsArrayTypeUnsafe()); | |||
10855 | ||||
10856 | uint64_t Elements = CAT->getSize().getZExtValue(); | |||
10857 | Result = APValue(APValue::UninitArray(), Elements, Elements); | |||
10858 | ||||
10859 | LValue Subobject = This; | |||
10860 | Subobject.addArray(Info, E, CAT); | |||
10861 | ||||
10862 | bool Success = true; | |||
10863 | for (EvalInfo::ArrayInitLoopIndex Index(Info); Index != Elements; ++Index) { | |||
10864 | if (!EvaluateInPlace(Result.getArrayInitializedElt(Index), | |||
10865 | Info, Subobject, E->getSubExpr()) || | |||
10866 | !HandleLValueArrayAdjustment(Info, E, Subobject, | |||
10867 | CAT->getElementType(), 1)) { | |||
10868 | if (!Info.noteFailure()) | |||
10869 | return false; | |||
10870 | Success = false; | |||
10871 | } | |||
10872 | } | |||
10873 | ||||
10874 | return Success; | |||
10875 | } | |||
10876 | ||||
10877 | bool ArrayExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E) { | |||
10878 | return VisitCXXConstructExpr(E, This, &Result, E->getType()); | |||
10879 | } | |||
10880 | ||||
10881 | bool ArrayExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E, | |||
10882 | const LValue &Subobject, | |||
10883 | APValue *Value, | |||
10884 | QualType Type) { | |||
10885 | bool HadZeroInit = Value->hasValue(); | |||
10886 | ||||
10887 | if (const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(Type)) { | |||
10888 | unsigned FinalSize = CAT->getSize().getZExtValue(); | |||
10889 | ||||
10890 | // Preserve the array filler if we had prior zero-initialization. | |||
10891 | APValue Filler = | |||
10892 | HadZeroInit && Value->hasArrayFiller() ? Value->getArrayFiller() | |||
10893 | : APValue(); | |||
10894 | ||||
10895 | *Value = APValue(APValue::UninitArray(), 0, FinalSize); | |||
10896 | if (FinalSize == 0) | |||
10897 | return true; | |||
10898 | ||||
10899 | bool HasTrivialConstructor = CheckTrivialDefaultConstructor( | |||
10900 | Info, E->getExprLoc(), E->getConstructor(), | |||
10901 | E->requiresZeroInitialization()); | |||
10902 | LValue ArrayElt = Subobject; | |||
10903 | ArrayElt.addArray(Info, E, CAT); | |||
10904 | // We do the whole initialization in two passes, first for just one element, | |||
10905 | // then for the whole array. It's possible we may find out we can't do const | |||
10906 | // init in the first pass, in which case we avoid allocating a potentially | |||
10907 | // large array. We don't do more passes because expanding array requires | |||
10908 | // copying the data, which is wasteful. | |||
10909 | for (const unsigned N : {1u, FinalSize}) { | |||
10910 | unsigned OldElts = Value->getArrayInitializedElts(); | |||
10911 | if (OldElts == N) | |||
10912 | break; | |||
10913 | ||||
10914 | // Expand the array to appropriate size. | |||
10915 | APValue NewValue(APValue::UninitArray(), N, FinalSize); | |||
10916 | for (unsigned I = 0; I < OldElts; ++I) | |||
10917 | NewValue.getArrayInitializedElt(I).swap( | |||
10918 | Value->getArrayInitializedElt(I)); | |||
10919 | Value->swap(NewValue); | |||
10920 | ||||
10921 | if (HadZeroInit) | |||
10922 | for (unsigned I = OldElts; I < N; ++I) | |||
10923 | Value->getArrayInitializedElt(I) = Filler; | |||
10924 | ||||
10925 | if (HasTrivialConstructor && N == FinalSize && FinalSize != 1) { | |||
10926 | // If we have a trivial constructor, only evaluate it once and copy | |||
10927 | // the result into all the array elements. | |||
10928 | APValue &FirstResult = Value->getArrayInitializedElt(0); | |||
10929 | for (unsigned I = OldElts; I < FinalSize; ++I) | |||
10930 | Value->getArrayInitializedElt(I) = FirstResult; | |||
10931 | } else { | |||
10932 | for (unsigned I = OldElts; I < N; ++I) { | |||
10933 | if (!VisitCXXConstructExpr(E, ArrayElt, | |||
10934 | &Value->getArrayInitializedElt(I), | |||
10935 | CAT->getElementType()) || | |||
10936 | !HandleLValueArrayAdjustment(Info, E, ArrayElt, | |||
10937 | CAT->getElementType(), 1)) | |||
10938 | return false; | |||
10939 | // When checking for const initilization any diagnostic is considered | |||
10940 | // an error. | |||
10941 | if (Info.EvalStatus.Diag && !Info.EvalStatus.Diag->empty() && | |||
10942 | !Info.keepEvaluatingAfterFailure()) | |||
10943 | return false; | |||
10944 | } | |||
10945 | } | |||
10946 | } | |||
10947 | ||||
10948 | return true; | |||
10949 | } | |||
10950 | ||||
10951 | if (!Type->isRecordType()) | |||
10952 | return Error(E); | |||
10953 | ||||
10954 | return RecordExprEvaluator(Info, Subobject, *Value) | |||
10955 | .VisitCXXConstructExpr(E, Type); | |||
10956 | } | |||
10957 | ||||
10958 | bool ArrayExprEvaluator::VisitCXXParenListInitExpr( | |||
10959 | const CXXParenListInitExpr *E) { | |||
10960 | assert(dyn_cast<ConstantArrayType>(E->getType()) &&(static_cast <bool> (dyn_cast<ConstantArrayType>( E->getType()) && "Expression result is not a constant array type" ) ? void (0) : __assert_fail ("dyn_cast<ConstantArrayType>(E->getType()) && \"Expression result is not a constant array type\"" , "clang/lib/AST/ExprConstant.cpp", 10961, __extension__ __PRETTY_FUNCTION__ )) | |||
10961 | "Expression result is not a constant array type")(static_cast <bool> (dyn_cast<ConstantArrayType>( E->getType()) && "Expression result is not a constant array type" ) ? void (0) : __assert_fail ("dyn_cast<ConstantArrayType>(E->getType()) && \"Expression result is not a constant array type\"" , "clang/lib/AST/ExprConstant.cpp", 10961, __extension__ __PRETTY_FUNCTION__ )); | |||
10962 | ||||
10963 | return VisitCXXParenListOrInitListExpr(E, E->getInitExprs(), | |||
10964 | E->getArrayFiller()); | |||
10965 | } | |||
10966 | ||||
10967 | //===----------------------------------------------------------------------===// | |||
10968 | // Integer Evaluation | |||
10969 | // | |||
10970 | // As a GNU extension, we support casting pointers to sufficiently-wide integer | |||
10971 | // types and back in constant folding. Integer values are thus represented | |||
10972 | // either as an integer-valued APValue, or as an lvalue-valued APValue. | |||
10973 | //===----------------------------------------------------------------------===// | |||
10974 | ||||
10975 | namespace { | |||
10976 | class IntExprEvaluator | |||
10977 | : public ExprEvaluatorBase<IntExprEvaluator> { | |||
10978 | APValue &Result; | |||
10979 | public: | |||
10980 | IntExprEvaluator(EvalInfo &info, APValue &result) | |||
10981 | : ExprEvaluatorBaseTy(info), Result(result) {} | |||
10982 | ||||
10983 | bool Success(const llvm::APSInt &SI, const Expr *E, APValue &Result) { | |||
10984 | assert(E->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getType()->isIntegralOrEnumerationType () && "Invalid evaluation result.") ? void (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 10985, __extension__ __PRETTY_FUNCTION__ )) | |||
10985 | "Invalid evaluation result.")(static_cast <bool> (E->getType()->isIntegralOrEnumerationType () && "Invalid evaluation result.") ? void (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 10985, __extension__ __PRETTY_FUNCTION__ )); | |||
10986 | assert(SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() &&(static_cast <bool> (SI.isSigned() == E->getType()-> isSignedIntegerOrEnumerationType() && "Invalid evaluation result." ) ? void (0) : __assert_fail ("SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 10987, __extension__ __PRETTY_FUNCTION__ )) | |||
10987 | "Invalid evaluation result.")(static_cast <bool> (SI.isSigned() == E->getType()-> isSignedIntegerOrEnumerationType() && "Invalid evaluation result." ) ? void (0) : __assert_fail ("SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 10987, __extension__ __PRETTY_FUNCTION__ )); | |||
10988 | assert(SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&(static_cast <bool> (SI.getBitWidth() == Info.Ctx.getIntWidth (E->getType()) && "Invalid evaluation result.") ? void (0) : __assert_fail ("SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 10989, __extension__ __PRETTY_FUNCTION__ )) | |||
10989 | "Invalid evaluation result.")(static_cast <bool> (SI.getBitWidth() == Info.Ctx.getIntWidth (E->getType()) && "Invalid evaluation result.") ? void (0) : __assert_fail ("SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 10989, __extension__ __PRETTY_FUNCTION__ )); | |||
10990 | Result = APValue(SI); | |||
10991 | return true; | |||
10992 | } | |||
10993 | bool Success(const llvm::APSInt &SI, const Expr *E) { | |||
10994 | return Success(SI, E, Result); | |||
10995 | } | |||
10996 | ||||
10997 | bool Success(const llvm::APInt &I, const Expr *E, APValue &Result) { | |||
10998 | assert(E->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getType()->isIntegralOrEnumerationType () && "Invalid evaluation result.") ? void (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 10999, __extension__ __PRETTY_FUNCTION__ )) | |||
10999 | "Invalid evaluation result.")(static_cast <bool> (E->getType()->isIntegralOrEnumerationType () && "Invalid evaluation result.") ? void (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 10999, __extension__ __PRETTY_FUNCTION__ )); | |||
11000 | assert(I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&(static_cast <bool> (I.getBitWidth() == Info.Ctx.getIntWidth (E->getType()) && "Invalid evaluation result.") ? void (0) : __assert_fail ("I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 11001, __extension__ __PRETTY_FUNCTION__ )) | |||
11001 | "Invalid evaluation result.")(static_cast <bool> (I.getBitWidth() == Info.Ctx.getIntWidth (E->getType()) && "Invalid evaluation result.") ? void (0) : __assert_fail ("I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 11001, __extension__ __PRETTY_FUNCTION__ )); | |||
11002 | Result = APValue(APSInt(I)); | |||
11003 | Result.getInt().setIsUnsigned( | |||
11004 | E->getType()->isUnsignedIntegerOrEnumerationType()); | |||
11005 | return true; | |||
11006 | } | |||
11007 | bool Success(const llvm::APInt &I, const Expr *E) { | |||
11008 | return Success(I, E, Result); | |||
11009 | } | |||
11010 | ||||
11011 | bool Success(uint64_t Value, const Expr *E, APValue &Result) { | |||
11012 | assert(E->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getType()->isIntegralOrEnumerationType () && "Invalid evaluation result.") ? void (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 11013, __extension__ __PRETTY_FUNCTION__ )) | |||
11013 | "Invalid evaluation result.")(static_cast <bool> (E->getType()->isIntegralOrEnumerationType () && "Invalid evaluation result.") ? void (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 11013, __extension__ __PRETTY_FUNCTION__ )); | |||
11014 | Result = APValue(Info.Ctx.MakeIntValue(Value, E->getType())); | |||
11015 | return true; | |||
11016 | } | |||
11017 | bool Success(uint64_t Value, const Expr *E) { | |||
11018 | return Success(Value, E, Result); | |||
11019 | } | |||
11020 | ||||
11021 | bool Success(CharUnits Size, const Expr *E) { | |||
11022 | return Success(Size.getQuantity(), E); | |||
11023 | } | |||
11024 | ||||
11025 | bool Success(const APValue &V, const Expr *E) { | |||
11026 | if (V.isLValue() || V.isAddrLabelDiff() || V.isIndeterminate()) { | |||
11027 | Result = V; | |||
11028 | return true; | |||
11029 | } | |||
11030 | return Success(V.getInt(), E); | |||
11031 | } | |||
11032 | ||||
11033 | bool ZeroInitialization(const Expr *E) { return Success(0, E); } | |||
11034 | ||||
11035 | //===--------------------------------------------------------------------===// | |||
11036 | // Visitor Methods | |||
11037 | //===--------------------------------------------------------------------===// | |||
11038 | ||||
11039 | bool VisitIntegerLiteral(const IntegerLiteral *E) { | |||
11040 | return Success(E->getValue(), E); | |||
11041 | } | |||
11042 | bool VisitCharacterLiteral(const CharacterLiteral *E) { | |||
11043 | return Success(E->getValue(), E); | |||
11044 | } | |||
11045 | ||||
11046 | bool CheckReferencedDecl(const Expr *E, const Decl *D); | |||
11047 | bool VisitDeclRefExpr(const DeclRefExpr *E) { | |||
11048 | if (CheckReferencedDecl(E, E->getDecl())) | |||
11049 | return true; | |||
11050 | ||||
11051 | return ExprEvaluatorBaseTy::VisitDeclRefExpr(E); | |||
11052 | } | |||
11053 | bool VisitMemberExpr(const MemberExpr *E) { | |||
11054 | if (CheckReferencedDecl(E, E->getMemberDecl())) { | |||
11055 | VisitIgnoredBaseExpression(E->getBase()); | |||
11056 | return true; | |||
11057 | } | |||
11058 | ||||
11059 | return ExprEvaluatorBaseTy::VisitMemberExpr(E); | |||
11060 | } | |||
11061 | ||||
11062 | bool VisitCallExpr(const CallExpr *E); | |||
11063 | bool VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp); | |||
11064 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
11065 | bool VisitOffsetOfExpr(const OffsetOfExpr *E); | |||
11066 | bool VisitUnaryOperator(const UnaryOperator *E); | |||
11067 | ||||
11068 | bool VisitCastExpr(const CastExpr* E); | |||
11069 | bool VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E); | |||
11070 | ||||
11071 | bool VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { | |||
11072 | return Success(E->getValue(), E); | |||
11073 | } | |||
11074 | ||||
11075 | bool VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *E) { | |||
11076 | return Success(E->getValue(), E); | |||
11077 | } | |||
11078 | ||||
11079 | bool VisitArrayInitIndexExpr(const ArrayInitIndexExpr *E) { | |||
11080 | if (Info.ArrayInitIndex == uint64_t(-1)) { | |||
11081 | // We were asked to evaluate this subexpression independent of the | |||
11082 | // enclosing ArrayInitLoopExpr. We can't do that. | |||
11083 | Info.FFDiag(E); | |||
11084 | return false; | |||
11085 | } | |||
11086 | return Success(Info.ArrayInitIndex, E); | |||
11087 | } | |||
11088 | ||||
11089 | // Note, GNU defines __null as an integer, not a pointer. | |||
11090 | bool VisitGNUNullExpr(const GNUNullExpr *E) { | |||
11091 | return ZeroInitialization(E); | |||
11092 | } | |||
11093 | ||||
11094 | bool VisitTypeTraitExpr(const TypeTraitExpr *E) { | |||
11095 | return Success(E->getValue(), E); | |||
11096 | } | |||
11097 | ||||
11098 | bool VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) { | |||
11099 | return Success(E->getValue(), E); | |||
11100 | } | |||
11101 | ||||
11102 | bool VisitExpressionTraitExpr(const ExpressionTraitExpr *E) { | |||
11103 | return Success(E->getValue(), E); | |||
11104 | } | |||
11105 | ||||
11106 | bool VisitUnaryReal(const UnaryOperator *E); | |||
11107 | bool VisitUnaryImag(const UnaryOperator *E); | |||
11108 | ||||
11109 | bool VisitCXXNoexceptExpr(const CXXNoexceptExpr *E); | |||
11110 | bool VisitSizeOfPackExpr(const SizeOfPackExpr *E); | |||
11111 | bool VisitSourceLocExpr(const SourceLocExpr *E); | |||
11112 | bool VisitConceptSpecializationExpr(const ConceptSpecializationExpr *E); | |||
11113 | bool VisitRequiresExpr(const RequiresExpr *E); | |||
11114 | // FIXME: Missing: array subscript of vector, member of vector | |||
11115 | }; | |||
11116 | ||||
11117 | class FixedPointExprEvaluator | |||
11118 | : public ExprEvaluatorBase<FixedPointExprEvaluator> { | |||
11119 | APValue &Result; | |||
11120 | ||||
11121 | public: | |||
11122 | FixedPointExprEvaluator(EvalInfo &info, APValue &result) | |||
11123 | : ExprEvaluatorBaseTy(info), Result(result) {} | |||
11124 | ||||
11125 | bool Success(const llvm::APInt &I, const Expr *E) { | |||
11126 | return Success( | |||
11127 | APFixedPoint(I, Info.Ctx.getFixedPointSemantics(E->getType())), E); | |||
11128 | } | |||
11129 | ||||
11130 | bool Success(uint64_t Value, const Expr *E) { | |||
11131 | return Success( | |||
11132 | APFixedPoint(Value, Info.Ctx.getFixedPointSemantics(E->getType())), E); | |||
11133 | } | |||
11134 | ||||
11135 | bool Success(const APValue &V, const Expr *E) { | |||
11136 | return Success(V.getFixedPoint(), E); | |||
11137 | } | |||
11138 | ||||
11139 | bool Success(const APFixedPoint &V, const Expr *E) { | |||
11140 | assert(E->getType()->isFixedPointType() && "Invalid evaluation result.")(static_cast <bool> (E->getType()->isFixedPointType () && "Invalid evaluation result.") ? void (0) : __assert_fail ("E->getType()->isFixedPointType() && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 11140, __extension__ __PRETTY_FUNCTION__ )); | |||
11141 | assert(V.getWidth() == Info.Ctx.getIntWidth(E->getType()) &&(static_cast <bool> (V.getWidth() == Info.Ctx.getIntWidth (E->getType()) && "Invalid evaluation result.") ? void (0) : __assert_fail ("V.getWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 11142, __extension__ __PRETTY_FUNCTION__ )) | |||
11142 | "Invalid evaluation result.")(static_cast <bool> (V.getWidth() == Info.Ctx.getIntWidth (E->getType()) && "Invalid evaluation result.") ? void (0) : __assert_fail ("V.getWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "clang/lib/AST/ExprConstant.cpp", 11142, __extension__ __PRETTY_FUNCTION__ )); | |||
11143 | Result = APValue(V); | |||
11144 | return true; | |||
11145 | } | |||
11146 | ||||
11147 | //===--------------------------------------------------------------------===// | |||
11148 | // Visitor Methods | |||
11149 | //===--------------------------------------------------------------------===// | |||
11150 | ||||
11151 | bool VisitFixedPointLiteral(const FixedPointLiteral *E) { | |||
11152 | return Success(E->getValue(), E); | |||
11153 | } | |||
11154 | ||||
11155 | bool VisitCastExpr(const CastExpr *E); | |||
11156 | bool VisitUnaryOperator(const UnaryOperator *E); | |||
11157 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
11158 | }; | |||
11159 | } // end anonymous namespace | |||
11160 | ||||
11161 | /// EvaluateIntegerOrLValue - Evaluate an rvalue integral-typed expression, and | |||
11162 | /// produce either the integer value or a pointer. | |||
11163 | /// | |||
11164 | /// GCC has a heinous extension which folds casts between pointer types and | |||
11165 | /// pointer-sized integral types. We support this by allowing the evaluation of | |||
11166 | /// an integer rvalue to produce a pointer (represented as an lvalue) instead. | |||
11167 | /// Some simple arithmetic on such values is supported (they are treated much | |||
11168 | /// like char*). | |||
11169 | static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result, | |||
11170 | EvalInfo &Info) { | |||
11171 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 11171, __extension__ __PRETTY_FUNCTION__)); | |||
11172 | assert(E->isPRValue() && E->getType()->isIntegralOrEnumerationType())(static_cast <bool> (E->isPRValue() && E-> getType()->isIntegralOrEnumerationType()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isIntegralOrEnumerationType()" , "clang/lib/AST/ExprConstant.cpp", 11172, __extension__ __PRETTY_FUNCTION__ )); | |||
11173 | return IntExprEvaluator(Info, Result).Visit(E); | |||
11174 | } | |||
11175 | ||||
11176 | static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info) { | |||
11177 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 11177, __extension__ __PRETTY_FUNCTION__)); | |||
11178 | APValue Val; | |||
11179 | if (!EvaluateIntegerOrLValue(E, Val, Info)) | |||
11180 | return false; | |||
11181 | if (!Val.isInt()) { | |||
11182 | // FIXME: It would be better to produce the diagnostic for casting | |||
11183 | // a pointer to an integer. | |||
11184 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
11185 | return false; | |||
11186 | } | |||
11187 | Result = Val.getInt(); | |||
11188 | return true; | |||
11189 | } | |||
11190 | ||||
11191 | bool IntExprEvaluator::VisitSourceLocExpr(const SourceLocExpr *E) { | |||
11192 | APValue Evaluated = E->EvaluateInContext( | |||
11193 | Info.Ctx, Info.CurrentCall->CurSourceLocExprScope.getDefaultExpr()); | |||
11194 | return Success(Evaluated, E); | |||
11195 | } | |||
11196 | ||||
11197 | static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result, | |||
11198 | EvalInfo &Info) { | |||
11199 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 11199, __extension__ __PRETTY_FUNCTION__)); | |||
11200 | if (E->getType()->isFixedPointType()) { | |||
11201 | APValue Val; | |||
11202 | if (!FixedPointExprEvaluator(Info, Val).Visit(E)) | |||
11203 | return false; | |||
11204 | if (!Val.isFixedPoint()) | |||
11205 | return false; | |||
11206 | ||||
11207 | Result = Val.getFixedPoint(); | |||
11208 | return true; | |||
11209 | } | |||
11210 | return false; | |||
11211 | } | |||
11212 | ||||
11213 | static bool EvaluateFixedPointOrInteger(const Expr *E, APFixedPoint &Result, | |||
11214 | EvalInfo &Info) { | |||
11215 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 11215, __extension__ __PRETTY_FUNCTION__)); | |||
11216 | if (E->getType()->isIntegerType()) { | |||
11217 | auto FXSema = Info.Ctx.getFixedPointSemantics(E->getType()); | |||
11218 | APSInt Val; | |||
11219 | if (!EvaluateInteger(E, Val, Info)) | |||
11220 | return false; | |||
11221 | Result = APFixedPoint(Val, FXSema); | |||
11222 | return true; | |||
11223 | } else if (E->getType()->isFixedPointType()) { | |||
11224 | return EvaluateFixedPoint(E, Result, Info); | |||
11225 | } | |||
11226 | return false; | |||
11227 | } | |||
11228 | ||||
11229 | /// Check whether the given declaration can be directly converted to an integral | |||
11230 | /// rvalue. If not, no diagnostic is produced; there are other things we can | |||
11231 | /// try. | |||
11232 | bool IntExprEvaluator::CheckReferencedDecl(const Expr* E, const Decl* D) { | |||
11233 | // Enums are integer constant exprs. | |||
11234 | if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D)) { | |||
11235 | // Check for signedness/width mismatches between E type and ECD value. | |||
11236 | bool SameSign = (ECD->getInitVal().isSigned() | |||
11237 | == E->getType()->isSignedIntegerOrEnumerationType()); | |||
11238 | bool SameWidth = (ECD->getInitVal().getBitWidth() | |||
11239 | == Info.Ctx.getIntWidth(E->getType())); | |||
11240 | if (SameSign && SameWidth) | |||
11241 | return Success(ECD->getInitVal(), E); | |||
11242 | else { | |||
11243 | // Get rid of mismatch (otherwise Success assertions will fail) | |||
11244 | // by computing a new value matching the type of E. | |||
11245 | llvm::APSInt Val = ECD->getInitVal(); | |||
11246 | if (!SameSign) | |||
11247 | Val.setIsSigned(!ECD->getInitVal().isSigned()); | |||
11248 | if (!SameWidth) | |||
11249 | Val = Val.extOrTrunc(Info.Ctx.getIntWidth(E->getType())); | |||
11250 | return Success(Val, E); | |||
11251 | } | |||
11252 | } | |||
11253 | return false; | |||
11254 | } | |||
11255 | ||||
11256 | /// Values returned by __builtin_classify_type, chosen to match the values | |||
11257 | /// produced by GCC's builtin. | |||
11258 | enum class GCCTypeClass { | |||
11259 | None = -1, | |||
11260 | Void = 0, | |||
11261 | Integer = 1, | |||
11262 | // GCC reserves 2 for character types, but instead classifies them as | |||
11263 | // integers. | |||
11264 | Enum = 3, | |||
11265 | Bool = 4, | |||
11266 | Pointer = 5, | |||
11267 | // GCC reserves 6 for references, but appears to never use it (because | |||
11268 | // expressions never have reference type, presumably). | |||
11269 | PointerToDataMember = 7, | |||
11270 | RealFloat = 8, | |||
11271 | Complex = 9, | |||
11272 | // GCC reserves 10 for functions, but does not use it since GCC version 6 due | |||
11273 | // to decay to pointer. (Prior to version 6 it was only used in C++ mode). | |||
11274 | // GCC claims to reserve 11 for pointers to member functions, but *actually* | |||
11275 | // uses 12 for that purpose, same as for a class or struct. Maybe it | |||
11276 | // internally implements a pointer to member as a struct? Who knows. | |||
11277 | PointerToMemberFunction = 12, // Not a bug, see above. | |||
11278 | ClassOrStruct = 12, | |||
11279 | Union = 13, | |||
11280 | // GCC reserves 14 for arrays, but does not use it since GCC version 6 due to | |||
11281 | // decay to pointer. (Prior to version 6 it was only used in C++ mode). | |||
11282 | // GCC reserves 15 for strings, but actually uses 5 (pointer) for string | |||
11283 | // literals. | |||
11284 | }; | |||
11285 | ||||
11286 | /// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way | |||
11287 | /// as GCC. | |||
11288 | static GCCTypeClass | |||
11289 | EvaluateBuiltinClassifyType(QualType T, const LangOptions &LangOpts) { | |||
11290 | assert(!T->isDependentType() && "unexpected dependent type")(static_cast <bool> (!T->isDependentType() && "unexpected dependent type") ? void (0) : __assert_fail ("!T->isDependentType() && \"unexpected dependent type\"" , "clang/lib/AST/ExprConstant.cpp", 11290, __extension__ __PRETTY_FUNCTION__ )); | |||
11291 | ||||
11292 | QualType CanTy = T.getCanonicalType(); | |||
11293 | const BuiltinType *BT = dyn_cast<BuiltinType>(CanTy); | |||
11294 | ||||
11295 | switch (CanTy->getTypeClass()) { | |||
11296 | #define TYPE(ID, BASE) | |||
11297 | #define DEPENDENT_TYPE(ID, BASE) case Type::ID: | |||
11298 | #define NON_CANONICAL_TYPE(ID, BASE) case Type::ID: | |||
11299 | #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(ID, BASE) case Type::ID: | |||
11300 | #include "clang/AST/TypeNodes.inc" | |||
11301 | case Type::Auto: | |||
11302 | case Type::DeducedTemplateSpecialization: | |||
11303 | llvm_unreachable("unexpected non-canonical or dependent type")::llvm::llvm_unreachable_internal("unexpected non-canonical or dependent type" , "clang/lib/AST/ExprConstant.cpp", 11303); | |||
11304 | ||||
11305 | case Type::Builtin: | |||
11306 | switch (BT->getKind()) { | |||
11307 | #define BUILTIN_TYPE(ID, SINGLETON_ID) | |||
11308 | #define SIGNED_TYPE(ID, SINGLETON_ID) \ | |||
11309 | case BuiltinType::ID: return GCCTypeClass::Integer; | |||
11310 | #define FLOATING_TYPE(ID, SINGLETON_ID) \ | |||
11311 | case BuiltinType::ID: return GCCTypeClass::RealFloat; | |||
11312 | #define PLACEHOLDER_TYPE(ID, SINGLETON_ID) \ | |||
11313 | case BuiltinType::ID: break; | |||
11314 | #include "clang/AST/BuiltinTypes.def" | |||
11315 | case BuiltinType::Void: | |||
11316 | return GCCTypeClass::Void; | |||
11317 | ||||
11318 | case BuiltinType::Bool: | |||
11319 | return GCCTypeClass::Bool; | |||
11320 | ||||
11321 | case BuiltinType::Char_U: | |||
11322 | case BuiltinType::UChar: | |||
11323 | case BuiltinType::WChar_U: | |||
11324 | case BuiltinType::Char8: | |||
11325 | case BuiltinType::Char16: | |||
11326 | case BuiltinType::Char32: | |||
11327 | case BuiltinType::UShort: | |||
11328 | case BuiltinType::UInt: | |||
11329 | case BuiltinType::ULong: | |||
11330 | case BuiltinType::ULongLong: | |||
11331 | case BuiltinType::UInt128: | |||
11332 | return GCCTypeClass::Integer; | |||
11333 | ||||
11334 | case BuiltinType::UShortAccum: | |||
11335 | case BuiltinType::UAccum: | |||
11336 | case BuiltinType::ULongAccum: | |||
11337 | case BuiltinType::UShortFract: | |||
11338 | case BuiltinType::UFract: | |||
11339 | case BuiltinType::ULongFract: | |||
11340 | case BuiltinType::SatUShortAccum: | |||
11341 | case BuiltinType::SatUAccum: | |||
11342 | case BuiltinType::SatULongAccum: | |||
11343 | case BuiltinType::SatUShortFract: | |||
11344 | case BuiltinType::SatUFract: | |||
11345 | case BuiltinType::SatULongFract: | |||
11346 | return GCCTypeClass::None; | |||
11347 | ||||
11348 | case BuiltinType::NullPtr: | |||
11349 | ||||
11350 | case BuiltinType::ObjCId: | |||
11351 | case BuiltinType::ObjCClass: | |||
11352 | case BuiltinType::ObjCSel: | |||
11353 | #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \ | |||
11354 | case BuiltinType::Id: | |||
11355 | #include "clang/Basic/OpenCLImageTypes.def" | |||
11356 | #define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \ | |||
11357 | case BuiltinType::Id: | |||
11358 | #include "clang/Basic/OpenCLExtensionTypes.def" | |||
11359 | case BuiltinType::OCLSampler: | |||
11360 | case BuiltinType::OCLEvent: | |||
11361 | case BuiltinType::OCLClkEvent: | |||
11362 | case BuiltinType::OCLQueue: | |||
11363 | case BuiltinType::OCLReserveID: | |||
11364 | #define SVE_TYPE(Name, Id, SingletonId) \ | |||
11365 | case BuiltinType::Id: | |||
11366 | #include "clang/Basic/AArch64SVEACLETypes.def" | |||
11367 | #define PPC_VECTOR_TYPE(Name, Id, Size) \ | |||
11368 | case BuiltinType::Id: | |||
11369 | #include "clang/Basic/PPCTypes.def" | |||
11370 | #define RVV_TYPE(Name, Id, SingletonId) case BuiltinType::Id: | |||
11371 | #include "clang/Basic/RISCVVTypes.def" | |||
11372 | #define WASM_TYPE(Name, Id, SingletonId) case BuiltinType::Id: | |||
11373 | #include "clang/Basic/WebAssemblyReferenceTypes.def" | |||
11374 | return GCCTypeClass::None; | |||
11375 | ||||
11376 | case BuiltinType::Dependent: | |||
11377 | llvm_unreachable("unexpected dependent type")::llvm::llvm_unreachable_internal("unexpected dependent type" , "clang/lib/AST/ExprConstant.cpp", 11377); | |||
11378 | }; | |||
11379 | llvm_unreachable("unexpected placeholder type")::llvm::llvm_unreachable_internal("unexpected placeholder type" , "clang/lib/AST/ExprConstant.cpp", 11379); | |||
11380 | ||||
11381 | case Type::Enum: | |||
11382 | return LangOpts.CPlusPlus ? GCCTypeClass::Enum : GCCTypeClass::Integer; | |||
11383 | ||||
11384 | case Type::Pointer: | |||
11385 | case Type::ConstantArray: | |||
11386 | case Type::VariableArray: | |||
11387 | case Type::IncompleteArray: | |||
11388 | case Type::FunctionNoProto: | |||
11389 | case Type::FunctionProto: | |||
11390 | return GCCTypeClass::Pointer; | |||
11391 | ||||
11392 | case Type::MemberPointer: | |||
11393 | return CanTy->isMemberDataPointerType() | |||
11394 | ? GCCTypeClass::PointerToDataMember | |||
11395 | : GCCTypeClass::PointerToMemberFunction; | |||
11396 | ||||
11397 | case Type::Complex: | |||
11398 | return GCCTypeClass::Complex; | |||
11399 | ||||
11400 | case Type::Record: | |||
11401 | return CanTy->isUnionType() ? GCCTypeClass::Union | |||
11402 | : GCCTypeClass::ClassOrStruct; | |||
11403 | ||||
11404 | case Type::Atomic: | |||
11405 | // GCC classifies _Atomic T the same as T. | |||
11406 | return EvaluateBuiltinClassifyType( | |||
11407 | CanTy->castAs<AtomicType>()->getValueType(), LangOpts); | |||
11408 | ||||
11409 | case Type::BlockPointer: | |||
11410 | case Type::Vector: | |||
11411 | case Type::ExtVector: | |||
11412 | case Type::ConstantMatrix: | |||
11413 | case Type::ObjCObject: | |||
11414 | case Type::ObjCInterface: | |||
11415 | case Type::ObjCObjectPointer: | |||
11416 | case Type::Pipe: | |||
11417 | case Type::BitInt: | |||
11418 | // GCC classifies vectors as None. We follow its lead and classify all | |||
11419 | // other types that don't fit into the regular classification the same way. | |||
11420 | return GCCTypeClass::None; | |||
11421 | ||||
11422 | case Type::LValueReference: | |||
11423 | case Type::RValueReference: | |||
11424 | llvm_unreachable("invalid type for expression")::llvm::llvm_unreachable_internal("invalid type for expression" , "clang/lib/AST/ExprConstant.cpp", 11424); | |||
11425 | } | |||
11426 | ||||
11427 | llvm_unreachable("unexpected type class")::llvm::llvm_unreachable_internal("unexpected type class", "clang/lib/AST/ExprConstant.cpp" , 11427); | |||
11428 | } | |||
11429 | ||||
11430 | /// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way | |||
11431 | /// as GCC. | |||
11432 | static GCCTypeClass | |||
11433 | EvaluateBuiltinClassifyType(const CallExpr *E, const LangOptions &LangOpts) { | |||
11434 | // If no argument was supplied, default to None. This isn't | |||
11435 | // ideal, however it is what gcc does. | |||
11436 | if (E->getNumArgs() == 0) | |||
11437 | return GCCTypeClass::None; | |||
11438 | ||||
11439 | // FIXME: Bizarrely, GCC treats a call with more than one argument as not | |||
11440 | // being an ICE, but still folds it to a constant using the type of the first | |||
11441 | // argument. | |||
11442 | return EvaluateBuiltinClassifyType(E->getArg(0)->getType(), LangOpts); | |||
11443 | } | |||
11444 | ||||
11445 | /// EvaluateBuiltinConstantPForLValue - Determine the result of | |||
11446 | /// __builtin_constant_p when applied to the given pointer. | |||
11447 | /// | |||
11448 | /// A pointer is only "constant" if it is null (or a pointer cast to integer) | |||
11449 | /// or it points to the first character of a string literal. | |||
11450 | static bool EvaluateBuiltinConstantPForLValue(const APValue &LV) { | |||
11451 | APValue::LValueBase Base = LV.getLValueBase(); | |||
11452 | if (Base.isNull()) { | |||
11453 | // A null base is acceptable. | |||
11454 | return true; | |||
11455 | } else if (const Expr *E = Base.dyn_cast<const Expr *>()) { | |||
11456 | if (!isa<StringLiteral>(E)) | |||
11457 | return false; | |||
11458 | return LV.getLValueOffset().isZero(); | |||
11459 | } else if (Base.is<TypeInfoLValue>()) { | |||
11460 | // Surprisingly, GCC considers __builtin_constant_p(&typeid(int)) to | |||
11461 | // evaluate to true. | |||
11462 | return true; | |||
11463 | } else { | |||
11464 | // Any other base is not constant enough for GCC. | |||
11465 | return false; | |||
11466 | } | |||
11467 | } | |||
11468 | ||||
11469 | /// EvaluateBuiltinConstantP - Evaluate __builtin_constant_p as similarly to | |||
11470 | /// GCC as we can manage. | |||
11471 | static bool EvaluateBuiltinConstantP(EvalInfo &Info, const Expr *Arg) { | |||
11472 | // This evaluation is not permitted to have side-effects, so evaluate it in | |||
11473 | // a speculative evaluation context. | |||
11474 | SpeculativeEvaluationRAII SpeculativeEval(Info); | |||
11475 | ||||
11476 | // Constant-folding is always enabled for the operand of __builtin_constant_p | |||
11477 | // (even when the enclosing evaluation context otherwise requires a strict | |||
11478 | // language-specific constant expression). | |||
11479 | FoldConstant Fold(Info, true); | |||
11480 | ||||
11481 | QualType ArgType = Arg->getType(); | |||
11482 | ||||
11483 | // __builtin_constant_p always has one operand. The rules which gcc follows | |||
11484 | // are not precisely documented, but are as follows: | |||
11485 | // | |||
11486 | // - If the operand is of integral, floating, complex or enumeration type, | |||
11487 | // and can be folded to a known value of that type, it returns 1. | |||
11488 | // - If the operand can be folded to a pointer to the first character | |||
11489 | // of a string literal (or such a pointer cast to an integral type) | |||
11490 | // or to a null pointer or an integer cast to a pointer, it returns 1. | |||
11491 | // | |||
11492 | // Otherwise, it returns 0. | |||
11493 | // | |||
11494 | // FIXME: GCC also intends to return 1 for literals of aggregate types, but | |||
11495 | // its support for this did not work prior to GCC 9 and is not yet well | |||
11496 | // understood. | |||
11497 | if (ArgType->isIntegralOrEnumerationType() || ArgType->isFloatingType() || | |||
11498 | ArgType->isAnyComplexType() || ArgType->isPointerType() || | |||
11499 | ArgType->isNullPtrType()) { | |||
11500 | APValue V; | |||
11501 | if (!::EvaluateAsRValue(Info, Arg, V) || Info.EvalStatus.HasSideEffects) { | |||
11502 | Fold.keepDiagnostics(); | |||
11503 | return false; | |||
11504 | } | |||
11505 | ||||
11506 | // For a pointer (possibly cast to integer), there are special rules. | |||
11507 | if (V.getKind() == APValue::LValue) | |||
11508 | return EvaluateBuiltinConstantPForLValue(V); | |||
11509 | ||||
11510 | // Otherwise, any constant value is good enough. | |||
11511 | return V.hasValue(); | |||
11512 | } | |||
11513 | ||||
11514 | // Anything else isn't considered to be sufficiently constant. | |||
11515 | return false; | |||
11516 | } | |||
11517 | ||||
11518 | /// Retrieves the "underlying object type" of the given expression, | |||
11519 | /// as used by __builtin_object_size. | |||
11520 | static QualType getObjectType(APValue::LValueBase B) { | |||
11521 | if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) { | |||
11522 | if (const VarDecl *VD = dyn_cast<VarDecl>(D)) | |||
11523 | return VD->getType(); | |||
11524 | } else if (const Expr *E = B.dyn_cast<const Expr*>()) { | |||
11525 | if (isa<CompoundLiteralExpr>(E)) | |||
11526 | return E->getType(); | |||
11527 | } else if (B.is<TypeInfoLValue>()) { | |||
11528 | return B.getTypeInfoType(); | |||
11529 | } else if (B.is<DynamicAllocLValue>()) { | |||
11530 | return B.getDynamicAllocType(); | |||
11531 | } | |||
11532 | ||||
11533 | return QualType(); | |||
11534 | } | |||
11535 | ||||
11536 | /// A more selective version of E->IgnoreParenCasts for | |||
11537 | /// tryEvaluateBuiltinObjectSize. This ignores some casts/parens that serve only | |||
11538 | /// to change the type of E. | |||
11539 | /// Ex. For E = `(short*)((char*)(&foo))`, returns `&foo` | |||
11540 | /// | |||
11541 | /// Always returns an RValue with a pointer representation. | |||
11542 | static const Expr *ignorePointerCastsAndParens(const Expr *E) { | |||
11543 | assert(E->isPRValue() && E->getType()->hasPointerRepresentation())(static_cast <bool> (E->isPRValue() && E-> getType()->hasPointerRepresentation()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->hasPointerRepresentation()" , "clang/lib/AST/ExprConstant.cpp", 11543, __extension__ __PRETTY_FUNCTION__ )); | |||
11544 | ||||
11545 | auto *NoParens = E->IgnoreParens(); | |||
11546 | auto *Cast = dyn_cast<CastExpr>(NoParens); | |||
11547 | if (Cast == nullptr) | |||
11548 | return NoParens; | |||
11549 | ||||
11550 | // We only conservatively allow a few kinds of casts, because this code is | |||
11551 | // inherently a simple solution that seeks to support the common case. | |||
11552 | auto CastKind = Cast->getCastKind(); | |||
11553 | if (CastKind != CK_NoOp && CastKind != CK_BitCast && | |||
11554 | CastKind != CK_AddressSpaceConversion) | |||
11555 | return NoParens; | |||
11556 | ||||
11557 | auto *SubExpr = Cast->getSubExpr(); | |||
11558 | if (!SubExpr->getType()->hasPointerRepresentation() || !SubExpr->isPRValue()) | |||
11559 | return NoParens; | |||
11560 | return ignorePointerCastsAndParens(SubExpr); | |||
11561 | } | |||
11562 | ||||
11563 | /// Checks to see if the given LValue's Designator is at the end of the LValue's | |||
11564 | /// record layout. e.g. | |||
11565 | /// struct { struct { int a, b; } fst, snd; } obj; | |||
11566 | /// obj.fst // no | |||
11567 | /// obj.snd // yes | |||
11568 | /// obj.fst.a // no | |||
11569 | /// obj.fst.b // no | |||
11570 | /// obj.snd.a // no | |||
11571 | /// obj.snd.b // yes | |||
11572 | /// | |||
11573 | /// Please note: this function is specialized for how __builtin_object_size | |||
11574 | /// views "objects". | |||
11575 | /// | |||
11576 | /// If this encounters an invalid RecordDecl or otherwise cannot determine the | |||
11577 | /// correct result, it will always return true. | |||
11578 | static bool isDesignatorAtObjectEnd(const ASTContext &Ctx, const LValue &LVal) { | |||
11579 | assert(!LVal.Designator.Invalid)(static_cast <bool> (!LVal.Designator.Invalid) ? void ( 0) : __assert_fail ("!LVal.Designator.Invalid", "clang/lib/AST/ExprConstant.cpp" , 11579, __extension__ __PRETTY_FUNCTION__)); | |||
11580 | ||||
11581 | auto IsLastOrInvalidFieldDecl = [&Ctx](const FieldDecl *FD, bool &Invalid) { | |||
11582 | const RecordDecl *Parent = FD->getParent(); | |||
11583 | Invalid = Parent->isInvalidDecl(); | |||
11584 | if (Invalid || Parent->isUnion()) | |||
11585 | return true; | |||
11586 | const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(Parent); | |||
11587 | return FD->getFieldIndex() + 1 == Layout.getFieldCount(); | |||
11588 | }; | |||
11589 | ||||
11590 | auto &Base = LVal.getLValueBase(); | |||
11591 | if (auto *ME = dyn_cast_or_null<MemberExpr>(Base.dyn_cast<const Expr *>())) { | |||
11592 | if (auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) { | |||
11593 | bool Invalid; | |||
11594 | if (!IsLastOrInvalidFieldDecl(FD, Invalid)) | |||
11595 | return Invalid; | |||
11596 | } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(ME->getMemberDecl())) { | |||
11597 | for (auto *FD : IFD->chain()) { | |||
11598 | bool Invalid; | |||
11599 | if (!IsLastOrInvalidFieldDecl(cast<FieldDecl>(FD), Invalid)) | |||
11600 | return Invalid; | |||
11601 | } | |||
11602 | } | |||
11603 | } | |||
11604 | ||||
11605 | unsigned I = 0; | |||
11606 | QualType BaseType = getType(Base); | |||
11607 | if (LVal.Designator.FirstEntryIsAnUnsizedArray) { | |||
11608 | // If we don't know the array bound, conservatively assume we're looking at | |||
11609 | // the final array element. | |||
11610 | ++I; | |||
11611 | if (BaseType->isIncompleteArrayType()) | |||
11612 | BaseType = Ctx.getAsArrayType(BaseType)->getElementType(); | |||
11613 | else | |||
11614 | BaseType = BaseType->castAs<PointerType>()->getPointeeType(); | |||
11615 | } | |||
11616 | ||||
11617 | for (unsigned E = LVal.Designator.Entries.size(); I != E; ++I) { | |||
11618 | const auto &Entry = LVal.Designator.Entries[I]; | |||
11619 | if (BaseType->isArrayType()) { | |||
11620 | // Because __builtin_object_size treats arrays as objects, we can ignore | |||
11621 | // the index iff this is the last array in the Designator. | |||
11622 | if (I + 1 == E) | |||
11623 | return true; | |||
11624 | const auto *CAT = cast<ConstantArrayType>(Ctx.getAsArrayType(BaseType)); | |||
11625 | uint64_t Index = Entry.getAsArrayIndex(); | |||
11626 | if (Index + 1 != CAT->getSize()) | |||
11627 | return false; | |||
11628 | BaseType = CAT->getElementType(); | |||
11629 | } else if (BaseType->isAnyComplexType()) { | |||
11630 | const auto *CT = BaseType->castAs<ComplexType>(); | |||
11631 | uint64_t Index = Entry.getAsArrayIndex(); | |||
11632 | if (Index != 1) | |||
11633 | return false; | |||
11634 | BaseType = CT->getElementType(); | |||
11635 | } else if (auto *FD = getAsField(Entry)) { | |||
11636 | bool Invalid; | |||
11637 | if (!IsLastOrInvalidFieldDecl(FD, Invalid)) | |||
11638 | return Invalid; | |||
11639 | BaseType = FD->getType(); | |||
11640 | } else { | |||
11641 | assert(getAsBaseClass(Entry) && "Expecting cast to a base class")(static_cast <bool> (getAsBaseClass(Entry) && "Expecting cast to a base class" ) ? void (0) : __assert_fail ("getAsBaseClass(Entry) && \"Expecting cast to a base class\"" , "clang/lib/AST/ExprConstant.cpp", 11641, __extension__ __PRETTY_FUNCTION__ )); | |||
11642 | return false; | |||
11643 | } | |||
11644 | } | |||
11645 | return true; | |||
11646 | } | |||
11647 | ||||
11648 | /// Tests to see if the LValue has a user-specified designator (that isn't | |||
11649 | /// necessarily valid). Note that this always returns 'true' if the LValue has | |||
11650 | /// an unsized array as its first designator entry, because there's currently no | |||
11651 | /// way to tell if the user typed *foo or foo[0]. | |||
11652 | static bool refersToCompleteObject(const LValue &LVal) { | |||
11653 | if (LVal.Designator.Invalid) | |||
11654 | return false; | |||
11655 | ||||
11656 | if (!LVal.Designator.Entries.empty()) | |||
11657 | return LVal.Designator.isMostDerivedAnUnsizedArray(); | |||
11658 | ||||
11659 | if (!LVal.InvalidBase) | |||
11660 | return true; | |||
11661 | ||||
11662 | // If `E` is a MemberExpr, then the first part of the designator is hiding in | |||
11663 | // the LValueBase. | |||
11664 | const auto *E = LVal.Base.dyn_cast<const Expr *>(); | |||
11665 | return !E || !isa<MemberExpr>(E); | |||
11666 | } | |||
11667 | ||||
11668 | /// Attempts to detect a user writing into a piece of memory that's impossible | |||
11669 | /// to figure out the size of by just using types. | |||
11670 | static bool isUserWritingOffTheEnd(const ASTContext &Ctx, const LValue &LVal) { | |||
11671 | const SubobjectDesignator &Designator = LVal.Designator; | |||
11672 | // Notes: | |||
11673 | // - Users can only write off of the end when we have an invalid base. Invalid | |||
11674 | // bases imply we don't know where the memory came from. | |||
11675 | // - We used to be a bit more aggressive here; we'd only be conservative if | |||
11676 | // the array at the end was flexible, or if it had 0 or 1 elements. This | |||
11677 | // broke some common standard library extensions (PR30346), but was | |||
11678 | // otherwise seemingly fine. It may be useful to reintroduce this behavior | |||
11679 | // with some sort of list. OTOH, it seems that GCC is always | |||
11680 | // conservative with the last element in structs (if it's an array), so our | |||
11681 | // current behavior is more compatible than an explicit list approach would | |||
11682 | // be. | |||
11683 | auto isFlexibleArrayMember = [&] { | |||
11684 | using FAMKind = LangOptions::StrictFlexArraysLevelKind; | |||
11685 | FAMKind StrictFlexArraysLevel = | |||
11686 | Ctx.getLangOpts().getStrictFlexArraysLevel(); | |||
11687 | ||||
11688 | if (Designator.isMostDerivedAnUnsizedArray()) | |||
11689 | return true; | |||
11690 | ||||
11691 | if (StrictFlexArraysLevel == FAMKind::Default) | |||
11692 | return true; | |||
11693 | ||||
11694 | if (Designator.getMostDerivedArraySize() == 0 && | |||
11695 | StrictFlexArraysLevel != FAMKind::IncompleteOnly) | |||
11696 | return true; | |||
11697 | ||||
11698 | if (Designator.getMostDerivedArraySize() == 1 && | |||
11699 | StrictFlexArraysLevel == FAMKind::OneZeroOrIncomplete) | |||
11700 | return true; | |||
11701 | ||||
11702 | return false; | |||
11703 | }; | |||
11704 | ||||
11705 | return LVal.InvalidBase && | |||
11706 | Designator.Entries.size() == Designator.MostDerivedPathLength && | |||
11707 | Designator.MostDerivedIsArrayElement && isFlexibleArrayMember() && | |||
11708 | isDesignatorAtObjectEnd(Ctx, LVal); | |||
11709 | } | |||
11710 | ||||
11711 | /// Converts the given APInt to CharUnits, assuming the APInt is unsigned. | |||
11712 | /// Fails if the conversion would cause loss of precision. | |||
11713 | static bool convertUnsignedAPIntToCharUnits(const llvm::APInt &Int, | |||
11714 | CharUnits &Result) { | |||
11715 | auto CharUnitsMax = std::numeric_limits<CharUnits::QuantityType>::max(); | |||
11716 | if (Int.ugt(CharUnitsMax)) | |||
11717 | return false; | |||
11718 | Result = CharUnits::fromQuantity(Int.getZExtValue()); | |||
11719 | return true; | |||
11720 | } | |||
11721 | ||||
11722 | /// Helper for tryEvaluateBuiltinObjectSize -- Given an LValue, this will | |||
11723 | /// determine how many bytes exist from the beginning of the object to either | |||
11724 | /// the end of the current subobject, or the end of the object itself, depending | |||
11725 | /// on what the LValue looks like + the value of Type. | |||
11726 | /// | |||
11727 | /// If this returns false, the value of Result is undefined. | |||
11728 | static bool determineEndOffset(EvalInfo &Info, SourceLocation ExprLoc, | |||
11729 | unsigned Type, const LValue &LVal, | |||
11730 | CharUnits &EndOffset) { | |||
11731 | bool DetermineForCompleteObject = refersToCompleteObject(LVal); | |||
11732 | ||||
11733 | auto CheckedHandleSizeof = [&](QualType Ty, CharUnits &Result) { | |||
11734 | if (Ty.isNull() || Ty->isIncompleteType() || Ty->isFunctionType()) | |||
11735 | return false; | |||
11736 | return HandleSizeof(Info, ExprLoc, Ty, Result); | |||
11737 | }; | |||
11738 | ||||
11739 | // We want to evaluate the size of the entire object. This is a valid fallback | |||
11740 | // for when Type=1 and the designator is invalid, because we're asked for an | |||
11741 | // upper-bound. | |||
11742 | if (!(Type & 1) || LVal.Designator.Invalid || DetermineForCompleteObject) { | |||
11743 | // Type=3 wants a lower bound, so we can't fall back to this. | |||
11744 | if (Type == 3 && !DetermineForCompleteObject) | |||
11745 | return false; | |||
11746 | ||||
11747 | llvm::APInt APEndOffset; | |||
11748 | if (isBaseAnAllocSizeCall(LVal.getLValueBase()) && | |||
11749 | getBytesReturnedByAllocSizeCall(Info.Ctx, LVal, APEndOffset)) | |||
11750 | return convertUnsignedAPIntToCharUnits(APEndOffset, EndOffset); | |||
11751 | ||||
11752 | if (LVal.InvalidBase) | |||
11753 | return false; | |||
11754 | ||||
11755 | QualType BaseTy = getObjectType(LVal.getLValueBase()); | |||
11756 | return CheckedHandleSizeof(BaseTy, EndOffset); | |||
11757 | } | |||
11758 | ||||
11759 | // We want to evaluate the size of a subobject. | |||
11760 | const SubobjectDesignator &Designator = LVal.Designator; | |||
11761 | ||||
11762 | // The following is a moderately common idiom in C: | |||
11763 | // | |||
11764 | // struct Foo { int a; char c[1]; }; | |||
11765 | // struct Foo *F = (struct Foo *)malloc(sizeof(struct Foo) + strlen(Bar)); | |||
11766 | // strcpy(&F->c[0], Bar); | |||
11767 | // | |||
11768 | // In order to not break too much legacy code, we need to support it. | |||
11769 | if (isUserWritingOffTheEnd(Info.Ctx, LVal)) { | |||
11770 | // If we can resolve this to an alloc_size call, we can hand that back, | |||
11771 | // because we know for certain how many bytes there are to write to. | |||
11772 | llvm::APInt APEndOffset; | |||
11773 | if (isBaseAnAllocSizeCall(LVal.getLValueBase()) && | |||
11774 | getBytesReturnedByAllocSizeCall(Info.Ctx, LVal, APEndOffset)) | |||
11775 | return convertUnsignedAPIntToCharUnits(APEndOffset, EndOffset); | |||
11776 | ||||
11777 | // If we cannot determine the size of the initial allocation, then we can't | |||
11778 | // given an accurate upper-bound. However, we are still able to give | |||
11779 | // conservative lower-bounds for Type=3. | |||
11780 | if (Type == 1) | |||
11781 | return false; | |||
11782 | } | |||
11783 | ||||
11784 | CharUnits BytesPerElem; | |||
11785 | if (!CheckedHandleSizeof(Designator.MostDerivedType, BytesPerElem)) | |||
11786 | return false; | |||
11787 | ||||
11788 | // According to the GCC documentation, we want the size of the subobject | |||
11789 | // denoted by the pointer. But that's not quite right -- what we actually | |||
11790 | // want is the size of the immediately-enclosing array, if there is one. | |||
11791 | int64_t ElemsRemaining; | |||
11792 | if (Designator.MostDerivedIsArrayElement && | |||
11793 | Designator.Entries.size() == Designator.MostDerivedPathLength) { | |||
11794 | uint64_t ArraySize = Designator.getMostDerivedArraySize(); | |||
11795 | uint64_t ArrayIndex = Designator.Entries.back().getAsArrayIndex(); | |||
11796 | ElemsRemaining = ArraySize <= ArrayIndex ? 0 : ArraySize - ArrayIndex; | |||
11797 | } else { | |||
11798 | ElemsRemaining = Designator.isOnePastTheEnd() ? 0 : 1; | |||
11799 | } | |||
11800 | ||||
11801 | EndOffset = LVal.getLValueOffset() + BytesPerElem * ElemsRemaining; | |||
11802 | return true; | |||
11803 | } | |||
11804 | ||||
11805 | /// Tries to evaluate the __builtin_object_size for @p E. If successful, | |||
11806 | /// returns true and stores the result in @p Size. | |||
11807 | /// | |||
11808 | /// If @p WasError is non-null, this will report whether the failure to evaluate | |||
11809 | /// is to be treated as an Error in IntExprEvaluator. | |||
11810 | static bool tryEvaluateBuiltinObjectSize(const Expr *E, unsigned Type, | |||
11811 | EvalInfo &Info, uint64_t &Size) { | |||
11812 | // Determine the denoted object. | |||
11813 | LValue LVal; | |||
11814 | { | |||
11815 | // The operand of __builtin_object_size is never evaluated for side-effects. | |||
11816 | // If there are any, but we can determine the pointed-to object anyway, then | |||
11817 | // ignore the side-effects. | |||
11818 | SpeculativeEvaluationRAII SpeculativeEval(Info); | |||
11819 | IgnoreSideEffectsRAII Fold(Info); | |||
11820 | ||||
11821 | if (E->isGLValue()) { | |||
11822 | // It's possible for us to be given GLValues if we're called via | |||
11823 | // Expr::tryEvaluateObjectSize. | |||
11824 | APValue RVal; | |||
11825 | if (!EvaluateAsRValue(Info, E, RVal)) | |||
11826 | return false; | |||
11827 | LVal.setFrom(Info.Ctx, RVal); | |||
11828 | } else if (!EvaluatePointer(ignorePointerCastsAndParens(E), LVal, Info, | |||
11829 | /*InvalidBaseOK=*/true)) | |||
11830 | return false; | |||
11831 | } | |||
11832 | ||||
11833 | // If we point to before the start of the object, there are no accessible | |||
11834 | // bytes. | |||
11835 | if (LVal.getLValueOffset().isNegative()) { | |||
11836 | Size = 0; | |||
11837 | return true; | |||
11838 | } | |||
11839 | ||||
11840 | CharUnits EndOffset; | |||
11841 | if (!determineEndOffset(Info, E->getExprLoc(), Type, LVal, EndOffset)) | |||
11842 | return false; | |||
11843 | ||||
11844 | // If we've fallen outside of the end offset, just pretend there's nothing to | |||
11845 | // write to/read from. | |||
11846 | if (EndOffset <= LVal.getLValueOffset()) | |||
11847 | Size = 0; | |||
11848 | else | |||
11849 | Size = (EndOffset - LVal.getLValueOffset()).getQuantity(); | |||
11850 | return true; | |||
11851 | } | |||
11852 | ||||
11853 | bool IntExprEvaluator::VisitCallExpr(const CallExpr *E) { | |||
11854 | if (!IsConstantEvaluatedBuiltinCall(E)) | |||
11855 | return ExprEvaluatorBaseTy::VisitCallExpr(E); | |||
11856 | return VisitBuiltinCallExpr(E, E->getBuiltinCallee()); | |||
11857 | } | |||
11858 | ||||
11859 | static bool getBuiltinAlignArguments(const CallExpr *E, EvalInfo &Info, | |||
11860 | APValue &Val, APSInt &Alignment) { | |||
11861 | QualType SrcTy = E->getArg(0)->getType(); | |||
11862 | if (!getAlignmentArgument(E->getArg(1), SrcTy, Info, Alignment)) | |||
11863 | return false; | |||
11864 | // Even though we are evaluating integer expressions we could get a pointer | |||
11865 | // argument for the __builtin_is_aligned() case. | |||
11866 | if (SrcTy->isPointerType()) { | |||
11867 | LValue Ptr; | |||
11868 | if (!EvaluatePointer(E->getArg(0), Ptr, Info)) | |||
11869 | return false; | |||
11870 | Ptr.moveInto(Val); | |||
11871 | } else if (!SrcTy->isIntegralOrEnumerationType()) { | |||
11872 | Info.FFDiag(E->getArg(0)); | |||
11873 | return false; | |||
11874 | } else { | |||
11875 | APSInt SrcInt; | |||
11876 | if (!EvaluateInteger(E->getArg(0), SrcInt, Info)) | |||
11877 | return false; | |||
11878 | assert(SrcInt.getBitWidth() >= Alignment.getBitWidth() &&(static_cast <bool> (SrcInt.getBitWidth() >= Alignment .getBitWidth() && "Bit widths must be the same") ? void (0) : __assert_fail ("SrcInt.getBitWidth() >= Alignment.getBitWidth() && \"Bit widths must be the same\"" , "clang/lib/AST/ExprConstant.cpp", 11879, __extension__ __PRETTY_FUNCTION__ )) | |||
11879 | "Bit widths must be the same")(static_cast <bool> (SrcInt.getBitWidth() >= Alignment .getBitWidth() && "Bit widths must be the same") ? void (0) : __assert_fail ("SrcInt.getBitWidth() >= Alignment.getBitWidth() && \"Bit widths must be the same\"" , "clang/lib/AST/ExprConstant.cpp", 11879, __extension__ __PRETTY_FUNCTION__ )); | |||
11880 | Val = APValue(SrcInt); | |||
11881 | } | |||
11882 | assert(Val.hasValue())(static_cast <bool> (Val.hasValue()) ? void (0) : __assert_fail ("Val.hasValue()", "clang/lib/AST/ExprConstant.cpp", 11882, __extension__ __PRETTY_FUNCTION__)); | |||
11883 | return true; | |||
11884 | } | |||
11885 | ||||
11886 | bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E, | |||
11887 | unsigned BuiltinOp) { | |||
11888 | switch (BuiltinOp) { | |||
11889 | default: | |||
11890 | return false; | |||
11891 | ||||
11892 | case Builtin::BI__builtin_dynamic_object_size: | |||
11893 | case Builtin::BI__builtin_object_size: { | |||
11894 | // The type was checked when we built the expression. | |||
11895 | unsigned Type = | |||
11896 | E->getArg(1)->EvaluateKnownConstInt(Info.Ctx).getZExtValue(); | |||
11897 | assert(Type <= 3 && "unexpected type")(static_cast <bool> (Type <= 3 && "unexpected type" ) ? void (0) : __assert_fail ("Type <= 3 && \"unexpected type\"" , "clang/lib/AST/ExprConstant.cpp", 11897, __extension__ __PRETTY_FUNCTION__ )); | |||
11898 | ||||
11899 | uint64_t Size; | |||
11900 | if (tryEvaluateBuiltinObjectSize(E->getArg(0), Type, Info, Size)) | |||
11901 | return Success(Size, E); | |||
11902 | ||||
11903 | if (E->getArg(0)->HasSideEffects(Info.Ctx)) | |||
11904 | return Success((Type & 2) ? 0 : -1, E); | |||
11905 | ||||
11906 | // Expression had no side effects, but we couldn't statically determine the | |||
11907 | // size of the referenced object. | |||
11908 | switch (Info.EvalMode) { | |||
11909 | case EvalInfo::EM_ConstantExpression: | |||
11910 | case EvalInfo::EM_ConstantFold: | |||
11911 | case EvalInfo::EM_IgnoreSideEffects: | |||
11912 | // Leave it to IR generation. | |||
11913 | return Error(E); | |||
11914 | case EvalInfo::EM_ConstantExpressionUnevaluated: | |||
11915 | // Reduce it to a constant now. | |||
11916 | return Success((Type & 2) ? 0 : -1, E); | |||
11917 | } | |||
11918 | ||||
11919 | llvm_unreachable("unexpected EvalMode")::llvm::llvm_unreachable_internal("unexpected EvalMode", "clang/lib/AST/ExprConstant.cpp" , 11919); | |||
11920 | } | |||
11921 | ||||
11922 | case Builtin::BI__builtin_os_log_format_buffer_size: { | |||
11923 | analyze_os_log::OSLogBufferLayout Layout; | |||
11924 | analyze_os_log::computeOSLogBufferLayout(Info.Ctx, E, Layout); | |||
11925 | return Success(Layout.size().getQuantity(), E); | |||
11926 | } | |||
11927 | ||||
11928 | case Builtin::BI__builtin_is_aligned: { | |||
11929 | APValue Src; | |||
11930 | APSInt Alignment; | |||
11931 | if (!getBuiltinAlignArguments(E, Info, Src, Alignment)) | |||
11932 | return false; | |||
11933 | if (Src.isLValue()) { | |||
11934 | // If we evaluated a pointer, check the minimum known alignment. | |||
11935 | LValue Ptr; | |||
11936 | Ptr.setFrom(Info.Ctx, Src); | |||
11937 | CharUnits BaseAlignment = getBaseAlignment(Info, Ptr); | |||
11938 | CharUnits PtrAlign = BaseAlignment.alignmentAtOffset(Ptr.Offset); | |||
11939 | // We can return true if the known alignment at the computed offset is | |||
11940 | // greater than the requested alignment. | |||
11941 | assert(PtrAlign.isPowerOfTwo())(static_cast <bool> (PtrAlign.isPowerOfTwo()) ? void (0 ) : __assert_fail ("PtrAlign.isPowerOfTwo()", "clang/lib/AST/ExprConstant.cpp" , 11941, __extension__ __PRETTY_FUNCTION__)); | |||
11942 | assert(Alignment.isPowerOf2())(static_cast <bool> (Alignment.isPowerOf2()) ? void (0) : __assert_fail ("Alignment.isPowerOf2()", "clang/lib/AST/ExprConstant.cpp" , 11942, __extension__ __PRETTY_FUNCTION__)); | |||
11943 | if (PtrAlign.getQuantity() >= Alignment) | |||
11944 | return Success(1, E); | |||
11945 | // If the alignment is not known to be sufficient, some cases could still | |||
11946 | // be aligned at run time. However, if the requested alignment is less or | |||
11947 | // equal to the base alignment and the offset is not aligned, we know that | |||
11948 | // the run-time value can never be aligned. | |||
11949 | if (BaseAlignment.getQuantity() >= Alignment && | |||
11950 | PtrAlign.getQuantity() < Alignment) | |||
11951 | return Success(0, E); | |||
11952 | // Otherwise we can't infer whether the value is sufficiently aligned. | |||
11953 | // TODO: __builtin_is_aligned(__builtin_align_{down,up{(expr, N), N) | |||
11954 | // in cases where we can't fully evaluate the pointer. | |||
11955 | Info.FFDiag(E->getArg(0), diag::note_constexpr_alignment_compute) | |||
11956 | << Alignment; | |||
11957 | return false; | |||
11958 | } | |||
11959 | assert(Src.isInt())(static_cast <bool> (Src.isInt()) ? void (0) : __assert_fail ("Src.isInt()", "clang/lib/AST/ExprConstant.cpp", 11959, __extension__ __PRETTY_FUNCTION__)); | |||
11960 | return Success((Src.getInt() & (Alignment - 1)) == 0 ? 1 : 0, E); | |||
11961 | } | |||
11962 | case Builtin::BI__builtin_align_up: { | |||
11963 | APValue Src; | |||
11964 | APSInt Alignment; | |||
11965 | if (!getBuiltinAlignArguments(E, Info, Src, Alignment)) | |||
11966 | return false; | |||
11967 | if (!Src.isInt()) | |||
11968 | return Error(E); | |||
11969 | APSInt AlignedVal = | |||
11970 | APSInt((Src.getInt() + (Alignment - 1)) & ~(Alignment - 1), | |||
11971 | Src.getInt().isUnsigned()); | |||
11972 | assert(AlignedVal.getBitWidth() == Src.getInt().getBitWidth())(static_cast <bool> (AlignedVal.getBitWidth() == Src.getInt ().getBitWidth()) ? void (0) : __assert_fail ("AlignedVal.getBitWidth() == Src.getInt().getBitWidth()" , "clang/lib/AST/ExprConstant.cpp", 11972, __extension__ __PRETTY_FUNCTION__ )); | |||
11973 | return Success(AlignedVal, E); | |||
11974 | } | |||
11975 | case Builtin::BI__builtin_align_down: { | |||
11976 | APValue Src; | |||
11977 | APSInt Alignment; | |||
11978 | if (!getBuiltinAlignArguments(E, Info, Src, Alignment)) | |||
11979 | return false; | |||
11980 | if (!Src.isInt()) | |||
11981 | return Error(E); | |||
11982 | APSInt AlignedVal = | |||
11983 | APSInt(Src.getInt() & ~(Alignment - 1), Src.getInt().isUnsigned()); | |||
11984 | assert(AlignedVal.getBitWidth() == Src.getInt().getBitWidth())(static_cast <bool> (AlignedVal.getBitWidth() == Src.getInt ().getBitWidth()) ? void (0) : __assert_fail ("AlignedVal.getBitWidth() == Src.getInt().getBitWidth()" , "clang/lib/AST/ExprConstant.cpp", 11984, __extension__ __PRETTY_FUNCTION__ )); | |||
11985 | return Success(AlignedVal, E); | |||
11986 | } | |||
11987 | ||||
11988 | case Builtin::BI__builtin_bitreverse8: | |||
11989 | case Builtin::BI__builtin_bitreverse16: | |||
11990 | case Builtin::BI__builtin_bitreverse32: | |||
11991 | case Builtin::BI__builtin_bitreverse64: { | |||
11992 | APSInt Val; | |||
11993 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
11994 | return false; | |||
11995 | ||||
11996 | return Success(Val.reverseBits(), E); | |||
11997 | } | |||
11998 | ||||
11999 | case Builtin::BI__builtin_bswap16: | |||
12000 | case Builtin::BI__builtin_bswap32: | |||
12001 | case Builtin::BI__builtin_bswap64: { | |||
12002 | APSInt Val; | |||
12003 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
12004 | return false; | |||
12005 | ||||
12006 | return Success(Val.byteSwap(), E); | |||
12007 | } | |||
12008 | ||||
12009 | case Builtin::BI__builtin_classify_type: | |||
12010 | return Success((int)EvaluateBuiltinClassifyType(E, Info.getLangOpts()), E); | |||
12011 | ||||
12012 | case Builtin::BI__builtin_clrsb: | |||
12013 | case Builtin::BI__builtin_clrsbl: | |||
12014 | case Builtin::BI__builtin_clrsbll: { | |||
12015 | APSInt Val; | |||
12016 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
12017 | return false; | |||
12018 | ||||
12019 | return Success(Val.getBitWidth() - Val.getSignificantBits(), E); | |||
12020 | } | |||
12021 | ||||
12022 | case Builtin::BI__builtin_clz: | |||
12023 | case Builtin::BI__builtin_clzl: | |||
12024 | case Builtin::BI__builtin_clzll: | |||
12025 | case Builtin::BI__builtin_clzs: { | |||
12026 | APSInt Val; | |||
12027 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
12028 | return false; | |||
12029 | if (!Val) | |||
12030 | return Error(E); | |||
12031 | ||||
12032 | return Success(Val.countl_zero(), E); | |||
12033 | } | |||
12034 | ||||
12035 | case Builtin::BI__builtin_constant_p: { | |||
12036 | const Expr *Arg = E->getArg(0); | |||
12037 | if (EvaluateBuiltinConstantP(Info, Arg)) | |||
12038 | return Success(true, E); | |||
12039 | if (Info.InConstantContext || Arg->HasSideEffects(Info.Ctx)) { | |||
12040 | // Outside a constant context, eagerly evaluate to false in the presence | |||
12041 | // of side-effects in order to avoid -Wunsequenced false-positives in | |||
12042 | // a branch on __builtin_constant_p(expr). | |||
12043 | return Success(false, E); | |||
12044 | } | |||
12045 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
12046 | return false; | |||
12047 | } | |||
12048 | ||||
12049 | case Builtin::BI__builtin_is_constant_evaluated: { | |||
12050 | const auto *Callee = Info.CurrentCall->getCallee(); | |||
12051 | if (Info.InConstantContext && !Info.CheckingPotentialConstantExpression && | |||
12052 | (Info.CallStackDepth == 1 || | |||
12053 | (Info.CallStackDepth == 2 && Callee->isInStdNamespace() && | |||
12054 | Callee->getIdentifier() && | |||
12055 | Callee->getIdentifier()->isStr("is_constant_evaluated")))) { | |||
12056 | // FIXME: Find a better way to avoid duplicated diagnostics. | |||
12057 | if (Info.EvalStatus.Diag) | |||
12058 | Info.report((Info.CallStackDepth == 1) ? E->getExprLoc() | |||
12059 | : Info.CurrentCall->CallLoc, | |||
12060 | diag::warn_is_constant_evaluated_always_true_constexpr) | |||
12061 | << (Info.CallStackDepth == 1 ? "__builtin_is_constant_evaluated" | |||
12062 | : "std::is_constant_evaluated"); | |||
12063 | } | |||
12064 | ||||
12065 | return Success(Info.InConstantContext, E); | |||
12066 | } | |||
12067 | ||||
12068 | case Builtin::BI__builtin_ctz: | |||
12069 | case Builtin::BI__builtin_ctzl: | |||
12070 | case Builtin::BI__builtin_ctzll: | |||
12071 | case Builtin::BI__builtin_ctzs: { | |||
12072 | APSInt Val; | |||
12073 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
12074 | return false; | |||
12075 | if (!Val) | |||
12076 | return Error(E); | |||
12077 | ||||
12078 | return Success(Val.countr_zero(), E); | |||
12079 | } | |||
12080 | ||||
12081 | case Builtin::BI__builtin_eh_return_data_regno: { | |||
12082 | int Operand = E->getArg(0)->EvaluateKnownConstInt(Info.Ctx).getZExtValue(); | |||
12083 | Operand = Info.Ctx.getTargetInfo().getEHDataRegisterNumber(Operand); | |||
12084 | return Success(Operand, E); | |||
12085 | } | |||
12086 | ||||
12087 | case Builtin::BI__builtin_expect: | |||
12088 | case Builtin::BI__builtin_expect_with_probability: | |||
12089 | return Visit(E->getArg(0)); | |||
12090 | ||||
12091 | case Builtin::BI__builtin_ffs: | |||
12092 | case Builtin::BI__builtin_ffsl: | |||
12093 | case Builtin::BI__builtin_ffsll: { | |||
12094 | APSInt Val; | |||
12095 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
12096 | return false; | |||
12097 | ||||
12098 | unsigned N = Val.countr_zero(); | |||
12099 | return Success(N == Val.getBitWidth() ? 0 : N + 1, E); | |||
12100 | } | |||
12101 | ||||
12102 | case Builtin::BI__builtin_fpclassify: { | |||
12103 | APFloat Val(0.0); | |||
12104 | if (!EvaluateFloat(E->getArg(5), Val, Info)) | |||
12105 | return false; | |||
12106 | unsigned Arg; | |||
12107 | switch (Val.getCategory()) { | |||
12108 | case APFloat::fcNaN: Arg = 0; break; | |||
12109 | case APFloat::fcInfinity: Arg = 1; break; | |||
12110 | case APFloat::fcNormal: Arg = Val.isDenormal() ? 3 : 2; break; | |||
12111 | case APFloat::fcZero: Arg = 4; break; | |||
12112 | } | |||
12113 | return Visit(E->getArg(Arg)); | |||
12114 | } | |||
12115 | ||||
12116 | case Builtin::BI__builtin_isinf_sign: { | |||
12117 | APFloat Val(0.0); | |||
12118 | return EvaluateFloat(E->getArg(0), Val, Info) && | |||
12119 | Success(Val.isInfinity() ? (Val.isNegative() ? -1 : 1) : 0, E); | |||
12120 | } | |||
12121 | ||||
12122 | case Builtin::BI__builtin_isinf: { | |||
12123 | APFloat Val(0.0); | |||
12124 | return EvaluateFloat(E->getArg(0), Val, Info) && | |||
12125 | Success(Val.isInfinity() ? 1 : 0, E); | |||
12126 | } | |||
12127 | ||||
12128 | case Builtin::BI__builtin_isfinite: { | |||
12129 | APFloat Val(0.0); | |||
12130 | return EvaluateFloat(E->getArg(0), Val, Info) && | |||
12131 | Success(Val.isFinite() ? 1 : 0, E); | |||
12132 | } | |||
12133 | ||||
12134 | case Builtin::BI__builtin_isnan: { | |||
12135 | APFloat Val(0.0); | |||
12136 | return EvaluateFloat(E->getArg(0), Val, Info) && | |||
12137 | Success(Val.isNaN() ? 1 : 0, E); | |||
12138 | } | |||
12139 | ||||
12140 | case Builtin::BI__builtin_isnormal: { | |||
12141 | APFloat Val(0.0); | |||
12142 | return EvaluateFloat(E->getArg(0), Val, Info) && | |||
12143 | Success(Val.isNormal() ? 1 : 0, E); | |||
12144 | } | |||
12145 | ||||
12146 | case Builtin::BI__builtin_parity: | |||
12147 | case Builtin::BI__builtin_parityl: | |||
12148 | case Builtin::BI__builtin_parityll: { | |||
12149 | APSInt Val; | |||
12150 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
12151 | return false; | |||
12152 | ||||
12153 | return Success(Val.popcount() % 2, E); | |||
12154 | } | |||
12155 | ||||
12156 | case Builtin::BI__builtin_popcount: | |||
12157 | case Builtin::BI__builtin_popcountl: | |||
12158 | case Builtin::BI__builtin_popcountll: { | |||
12159 | APSInt Val; | |||
12160 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
12161 | return false; | |||
12162 | ||||
12163 | return Success(Val.popcount(), E); | |||
12164 | } | |||
12165 | ||||
12166 | case Builtin::BI__builtin_rotateleft8: | |||
12167 | case Builtin::BI__builtin_rotateleft16: | |||
12168 | case Builtin::BI__builtin_rotateleft32: | |||
12169 | case Builtin::BI__builtin_rotateleft64: | |||
12170 | case Builtin::BI_rotl8: // Microsoft variants of rotate right | |||
12171 | case Builtin::BI_rotl16: | |||
12172 | case Builtin::BI_rotl: | |||
12173 | case Builtin::BI_lrotl: | |||
12174 | case Builtin::BI_rotl64: { | |||
12175 | APSInt Val, Amt; | |||
12176 | if (!EvaluateInteger(E->getArg(0), Val, Info) || | |||
12177 | !EvaluateInteger(E->getArg(1), Amt, Info)) | |||
12178 | return false; | |||
12179 | ||||
12180 | return Success(Val.rotl(Amt.urem(Val.getBitWidth())), E); | |||
12181 | } | |||
12182 | ||||
12183 | case Builtin::BI__builtin_rotateright8: | |||
12184 | case Builtin::BI__builtin_rotateright16: | |||
12185 | case Builtin::BI__builtin_rotateright32: | |||
12186 | case Builtin::BI__builtin_rotateright64: | |||
12187 | case Builtin::BI_rotr8: // Microsoft variants of rotate right | |||
12188 | case Builtin::BI_rotr16: | |||
12189 | case Builtin::BI_rotr: | |||
12190 | case Builtin::BI_lrotr: | |||
12191 | case Builtin::BI_rotr64: { | |||
12192 | APSInt Val, Amt; | |||
12193 | if (!EvaluateInteger(E->getArg(0), Val, Info) || | |||
12194 | !EvaluateInteger(E->getArg(1), Amt, Info)) | |||
12195 | return false; | |||
12196 | ||||
12197 | return Success(Val.rotr(Amt.urem(Val.getBitWidth())), E); | |||
12198 | } | |||
12199 | ||||
12200 | case Builtin::BIstrlen: | |||
12201 | case Builtin::BIwcslen: | |||
12202 | // A call to strlen is not a constant expression. | |||
12203 | if (Info.getLangOpts().CPlusPlus11) | |||
12204 | Info.CCEDiag(E, diag::note_constexpr_invalid_function) | |||
12205 | << /*isConstexpr*/ 0 << /*isConstructor*/ 0 | |||
12206 | << ("'" + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'").str(); | |||
12207 | else | |||
12208 | Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
12209 | [[fallthrough]]; | |||
12210 | case Builtin::BI__builtin_strlen: | |||
12211 | case Builtin::BI__builtin_wcslen: { | |||
12212 | // As an extension, we support __builtin_strlen() as a constant expression, | |||
12213 | // and support folding strlen() to a constant. | |||
12214 | uint64_t StrLen; | |||
12215 | if (EvaluateBuiltinStrLen(E->getArg(0), StrLen, Info)) | |||
12216 | return Success(StrLen, E); | |||
12217 | return false; | |||
12218 | } | |||
12219 | ||||
12220 | case Builtin::BIstrcmp: | |||
12221 | case Builtin::BIwcscmp: | |||
12222 | case Builtin::BIstrncmp: | |||
12223 | case Builtin::BIwcsncmp: | |||
12224 | case Builtin::BImemcmp: | |||
12225 | case Builtin::BIbcmp: | |||
12226 | case Builtin::BIwmemcmp: | |||
12227 | // A call to strlen is not a constant expression. | |||
12228 | if (Info.getLangOpts().CPlusPlus11) | |||
12229 | Info.CCEDiag(E, diag::note_constexpr_invalid_function) | |||
12230 | << /*isConstexpr*/ 0 << /*isConstructor*/ 0 | |||
12231 | << ("'" + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'").str(); | |||
12232 | else | |||
12233 | Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
12234 | [[fallthrough]]; | |||
12235 | case Builtin::BI__builtin_strcmp: | |||
12236 | case Builtin::BI__builtin_wcscmp: | |||
12237 | case Builtin::BI__builtin_strncmp: | |||
12238 | case Builtin::BI__builtin_wcsncmp: | |||
12239 | case Builtin::BI__builtin_memcmp: | |||
12240 | case Builtin::BI__builtin_bcmp: | |||
12241 | case Builtin::BI__builtin_wmemcmp: { | |||
12242 | LValue String1, String2; | |||
12243 | if (!EvaluatePointer(E->getArg(0), String1, Info) || | |||
12244 | !EvaluatePointer(E->getArg(1), String2, Info)) | |||
12245 | return false; | |||
12246 | ||||
12247 | uint64_t MaxLength = uint64_t(-1); | |||
12248 | if (BuiltinOp != Builtin::BIstrcmp && | |||
12249 | BuiltinOp != Builtin::BIwcscmp && | |||
12250 | BuiltinOp != Builtin::BI__builtin_strcmp && | |||
12251 | BuiltinOp != Builtin::BI__builtin_wcscmp) { | |||
12252 | APSInt N; | |||
12253 | if (!EvaluateInteger(E->getArg(2), N, Info)) | |||
12254 | return false; | |||
12255 | MaxLength = N.getExtValue(); | |||
12256 | } | |||
12257 | ||||
12258 | // Empty substrings compare equal by definition. | |||
12259 | if (MaxLength == 0u) | |||
12260 | return Success(0, E); | |||
12261 | ||||
12262 | if (!String1.checkNullPointerForFoldAccess(Info, E, AK_Read) || | |||
12263 | !String2.checkNullPointerForFoldAccess(Info, E, AK_Read) || | |||
12264 | String1.Designator.Invalid || String2.Designator.Invalid) | |||
12265 | return false; | |||
12266 | ||||
12267 | QualType CharTy1 = String1.Designator.getType(Info.Ctx); | |||
12268 | QualType CharTy2 = String2.Designator.getType(Info.Ctx); | |||
12269 | ||||
12270 | bool IsRawByte = BuiltinOp == Builtin::BImemcmp || | |||
12271 | BuiltinOp == Builtin::BIbcmp || | |||
12272 | BuiltinOp == Builtin::BI__builtin_memcmp || | |||
12273 | BuiltinOp == Builtin::BI__builtin_bcmp; | |||
12274 | ||||
12275 | assert(IsRawByte ||(static_cast <bool> (IsRawByte || (Info.Ctx.hasSameUnqualifiedType ( CharTy1, E->getArg(0)->getType()->getPointeeType() ) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2 ))) ? void (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))" , "clang/lib/AST/ExprConstant.cpp", 12278, __extension__ __PRETTY_FUNCTION__ )) | |||
12276 | (Info.Ctx.hasSameUnqualifiedType((static_cast <bool> (IsRawByte || (Info.Ctx.hasSameUnqualifiedType ( CharTy1, E->getArg(0)->getType()->getPointeeType() ) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2 ))) ? void (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))" , "clang/lib/AST/ExprConstant.cpp", 12278, __extension__ __PRETTY_FUNCTION__ )) | |||
12277 | CharTy1, E->getArg(0)->getType()->getPointeeType()) &&(static_cast <bool> (IsRawByte || (Info.Ctx.hasSameUnqualifiedType ( CharTy1, E->getArg(0)->getType()->getPointeeType() ) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2 ))) ? void (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))" , "clang/lib/AST/ExprConstant.cpp", 12278, __extension__ __PRETTY_FUNCTION__ )) | |||
12278 | Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2)))(static_cast <bool> (IsRawByte || (Info.Ctx.hasSameUnqualifiedType ( CharTy1, E->getArg(0)->getType()->getPointeeType() ) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2 ))) ? void (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))" , "clang/lib/AST/ExprConstant.cpp", 12278, __extension__ __PRETTY_FUNCTION__ )); | |||
12279 | ||||
12280 | // For memcmp, allow comparing any arrays of '[[un]signed] char' or | |||
12281 | // 'char8_t', but no other types. | |||
12282 | if (IsRawByte && | |||
12283 | !(isOneByteCharacterType(CharTy1) && isOneByteCharacterType(CharTy2))) { | |||
12284 | // FIXME: Consider using our bit_cast implementation to support this. | |||
12285 | Info.FFDiag(E, diag::note_constexpr_memcmp_unsupported) | |||
12286 | << ("'" + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'").str() | |||
12287 | << CharTy1 << CharTy2; | |||
12288 | return false; | |||
12289 | } | |||
12290 | ||||
12291 | const auto &ReadCurElems = [&](APValue &Char1, APValue &Char2) { | |||
12292 | return handleLValueToRValueConversion(Info, E, CharTy1, String1, Char1) && | |||
12293 | handleLValueToRValueConversion(Info, E, CharTy2, String2, Char2) && | |||
12294 | Char1.isInt() && Char2.isInt(); | |||
12295 | }; | |||
12296 | const auto &AdvanceElems = [&] { | |||
12297 | return HandleLValueArrayAdjustment(Info, E, String1, CharTy1, 1) && | |||
12298 | HandleLValueArrayAdjustment(Info, E, String2, CharTy2, 1); | |||
12299 | }; | |||
12300 | ||||
12301 | bool StopAtNull = | |||
12302 | (BuiltinOp != Builtin::BImemcmp && BuiltinOp != Builtin::BIbcmp && | |||
12303 | BuiltinOp != Builtin::BIwmemcmp && | |||
12304 | BuiltinOp != Builtin::BI__builtin_memcmp && | |||
12305 | BuiltinOp != Builtin::BI__builtin_bcmp && | |||
12306 | BuiltinOp != Builtin::BI__builtin_wmemcmp); | |||
12307 | bool IsWide = BuiltinOp == Builtin::BIwcscmp || | |||
12308 | BuiltinOp == Builtin::BIwcsncmp || | |||
12309 | BuiltinOp == Builtin::BIwmemcmp || | |||
12310 | BuiltinOp == Builtin::BI__builtin_wcscmp || | |||
12311 | BuiltinOp == Builtin::BI__builtin_wcsncmp || | |||
12312 | BuiltinOp == Builtin::BI__builtin_wmemcmp; | |||
12313 | ||||
12314 | for (; MaxLength; --MaxLength) { | |||
12315 | APValue Char1, Char2; | |||
12316 | if (!ReadCurElems(Char1, Char2)) | |||
12317 | return false; | |||
12318 | if (Char1.getInt().ne(Char2.getInt())) { | |||
12319 | if (IsWide) // wmemcmp compares with wchar_t signedness. | |||
12320 | return Success(Char1.getInt() < Char2.getInt() ? -1 : 1, E); | |||
12321 | // memcmp always compares unsigned chars. | |||
12322 | return Success(Char1.getInt().ult(Char2.getInt()) ? -1 : 1, E); | |||
12323 | } | |||
12324 | if (StopAtNull && !Char1.getInt()) | |||
12325 | return Success(0, E); | |||
12326 | assert(!(StopAtNull && !Char2.getInt()))(static_cast <bool> (!(StopAtNull && !Char2.getInt ())) ? void (0) : __assert_fail ("!(StopAtNull && !Char2.getInt())" , "clang/lib/AST/ExprConstant.cpp", 12326, __extension__ __PRETTY_FUNCTION__ )); | |||
12327 | if (!AdvanceElems()) | |||
12328 | return false; | |||
12329 | } | |||
12330 | // We hit the strncmp / memcmp limit. | |||
12331 | return Success(0, E); | |||
12332 | } | |||
12333 | ||||
12334 | case Builtin::BI__atomic_always_lock_free: | |||
12335 | case Builtin::BI__atomic_is_lock_free: | |||
12336 | case Builtin::BI__c11_atomic_is_lock_free: { | |||
12337 | APSInt SizeVal; | |||
12338 | if (!EvaluateInteger(E->getArg(0), SizeVal, Info)) | |||
12339 | return false; | |||
12340 | ||||
12341 | // For __atomic_is_lock_free(sizeof(_Atomic(T))), if the size is a power | |||
12342 | // of two less than or equal to the maximum inline atomic width, we know it | |||
12343 | // is lock-free. If the size isn't a power of two, or greater than the | |||
12344 | // maximum alignment where we promote atomics, we know it is not lock-free | |||
12345 | // (at least not in the sense of atomic_is_lock_free). Otherwise, | |||
12346 | // the answer can only be determined at runtime; for example, 16-byte | |||
12347 | // atomics have lock-free implementations on some, but not all, | |||
12348 | // x86-64 processors. | |||
12349 | ||||
12350 | // Check power-of-two. | |||
12351 | CharUnits Size = CharUnits::fromQuantity(SizeVal.getZExtValue()); | |||
12352 | if (Size.isPowerOfTwo()) { | |||
12353 | // Check against inlining width. | |||
12354 | unsigned InlineWidthBits = | |||
12355 | Info.Ctx.getTargetInfo().getMaxAtomicInlineWidth(); | |||
12356 | if (Size <= Info.Ctx.toCharUnitsFromBits(InlineWidthBits)) { | |||
12357 | if (BuiltinOp == Builtin::BI__c11_atomic_is_lock_free || | |||
12358 | Size == CharUnits::One() || | |||
12359 | E->getArg(1)->isNullPointerConstant(Info.Ctx, | |||
12360 | Expr::NPC_NeverValueDependent)) | |||
12361 | // OK, we will inline appropriately-aligned operations of this size, | |||
12362 | // and _Atomic(T) is appropriately-aligned. | |||
12363 | return Success(1, E); | |||
12364 | ||||
12365 | QualType PointeeType = E->getArg(1)->IgnoreImpCasts()->getType()-> | |||
12366 | castAs<PointerType>()->getPointeeType(); | |||
12367 | if (!PointeeType->isIncompleteType() && | |||
12368 | Info.Ctx.getTypeAlignInChars(PointeeType) >= Size) { | |||
12369 | // OK, we will inline operations on this object. | |||
12370 | return Success(1, E); | |||
12371 | } | |||
12372 | } | |||
12373 | } | |||
12374 | ||||
12375 | return BuiltinOp == Builtin::BI__atomic_always_lock_free ? | |||
12376 | Success(0, E) : Error(E); | |||
12377 | } | |||
12378 | case Builtin::BI__builtin_add_overflow: | |||
12379 | case Builtin::BI__builtin_sub_overflow: | |||
12380 | case Builtin::BI__builtin_mul_overflow: | |||
12381 | case Builtin::BI__builtin_sadd_overflow: | |||
12382 | case Builtin::BI__builtin_uadd_overflow: | |||
12383 | case Builtin::BI__builtin_uaddl_overflow: | |||
12384 | case Builtin::BI__builtin_uaddll_overflow: | |||
12385 | case Builtin::BI__builtin_usub_overflow: | |||
12386 | case Builtin::BI__builtin_usubl_overflow: | |||
12387 | case Builtin::BI__builtin_usubll_overflow: | |||
12388 | case Builtin::BI__builtin_umul_overflow: | |||
12389 | case Builtin::BI__builtin_umull_overflow: | |||
12390 | case Builtin::BI__builtin_umulll_overflow: | |||
12391 | case Builtin::BI__builtin_saddl_overflow: | |||
12392 | case Builtin::BI__builtin_saddll_overflow: | |||
12393 | case Builtin::BI__builtin_ssub_overflow: | |||
12394 | case Builtin::BI__builtin_ssubl_overflow: | |||
12395 | case Builtin::BI__builtin_ssubll_overflow: | |||
12396 | case Builtin::BI__builtin_smul_overflow: | |||
12397 | case Builtin::BI__builtin_smull_overflow: | |||
12398 | case Builtin::BI__builtin_smulll_overflow: { | |||
12399 | LValue ResultLValue; | |||
12400 | APSInt LHS, RHS; | |||
12401 | ||||
12402 | QualType ResultType = E->getArg(2)->getType()->getPointeeType(); | |||
12403 | if (!EvaluateInteger(E->getArg(0), LHS, Info) || | |||
12404 | !EvaluateInteger(E->getArg(1), RHS, Info) || | |||
12405 | !EvaluatePointer(E->getArg(2), ResultLValue, Info)) | |||
12406 | return false; | |||
12407 | ||||
12408 | APSInt Result; | |||
12409 | bool DidOverflow = false; | |||
12410 | ||||
12411 | // If the types don't have to match, enlarge all 3 to the largest of them. | |||
12412 | if (BuiltinOp == Builtin::BI__builtin_add_overflow || | |||
12413 | BuiltinOp == Builtin::BI__builtin_sub_overflow || | |||
12414 | BuiltinOp == Builtin::BI__builtin_mul_overflow) { | |||
12415 | bool IsSigned = LHS.isSigned() || RHS.isSigned() || | |||
12416 | ResultType->isSignedIntegerOrEnumerationType(); | |||
12417 | bool AllSigned = LHS.isSigned() && RHS.isSigned() && | |||
12418 | ResultType->isSignedIntegerOrEnumerationType(); | |||
12419 | uint64_t LHSSize = LHS.getBitWidth(); | |||
12420 | uint64_t RHSSize = RHS.getBitWidth(); | |||
12421 | uint64_t ResultSize = Info.Ctx.getTypeSize(ResultType); | |||
12422 | uint64_t MaxBits = std::max(std::max(LHSSize, RHSSize), ResultSize); | |||
12423 | ||||
12424 | // Add an additional bit if the signedness isn't uniformly agreed to. We | |||
12425 | // could do this ONLY if there is a signed and an unsigned that both have | |||
12426 | // MaxBits, but the code to check that is pretty nasty. The issue will be | |||
12427 | // caught in the shrink-to-result later anyway. | |||
12428 | if (IsSigned && !AllSigned) | |||
12429 | ++MaxBits; | |||
12430 | ||||
12431 | LHS = APSInt(LHS.extOrTrunc(MaxBits), !IsSigned); | |||
12432 | RHS = APSInt(RHS.extOrTrunc(MaxBits), !IsSigned); | |||
12433 | Result = APSInt(MaxBits, !IsSigned); | |||
12434 | } | |||
12435 | ||||
12436 | // Find largest int. | |||
12437 | switch (BuiltinOp) { | |||
12438 | default: | |||
12439 | llvm_unreachable("Invalid value for BuiltinOp")::llvm::llvm_unreachable_internal("Invalid value for BuiltinOp" , "clang/lib/AST/ExprConstant.cpp", 12439); | |||
12440 | case Builtin::BI__builtin_add_overflow: | |||
12441 | case Builtin::BI__builtin_sadd_overflow: | |||
12442 | case Builtin::BI__builtin_saddl_overflow: | |||
12443 | case Builtin::BI__builtin_saddll_overflow: | |||
12444 | case Builtin::BI__builtin_uadd_overflow: | |||
12445 | case Builtin::BI__builtin_uaddl_overflow: | |||
12446 | case Builtin::BI__builtin_uaddll_overflow: | |||
12447 | Result = LHS.isSigned() ? LHS.sadd_ov(RHS, DidOverflow) | |||
12448 | : LHS.uadd_ov(RHS, DidOverflow); | |||
12449 | break; | |||
12450 | case Builtin::BI__builtin_sub_overflow: | |||
12451 | case Builtin::BI__builtin_ssub_overflow: | |||
12452 | case Builtin::BI__builtin_ssubl_overflow: | |||
12453 | case Builtin::BI__builtin_ssubll_overflow: | |||
12454 | case Builtin::BI__builtin_usub_overflow: | |||
12455 | case Builtin::BI__builtin_usubl_overflow: | |||
12456 | case Builtin::BI__builtin_usubll_overflow: | |||
12457 | Result = LHS.isSigned() ? LHS.ssub_ov(RHS, DidOverflow) | |||
12458 | : LHS.usub_ov(RHS, DidOverflow); | |||
12459 | break; | |||
12460 | case Builtin::BI__builtin_mul_overflow: | |||
12461 | case Builtin::BI__builtin_smul_overflow: | |||
12462 | case Builtin::BI__builtin_smull_overflow: | |||
12463 | case Builtin::BI__builtin_smulll_overflow: | |||
12464 | case Builtin::BI__builtin_umul_overflow: | |||
12465 | case Builtin::BI__builtin_umull_overflow: | |||
12466 | case Builtin::BI__builtin_umulll_overflow: | |||
12467 | Result = LHS.isSigned() ? LHS.smul_ov(RHS, DidOverflow) | |||
12468 | : LHS.umul_ov(RHS, DidOverflow); | |||
12469 | break; | |||
12470 | } | |||
12471 | ||||
12472 | // In the case where multiple sizes are allowed, truncate and see if | |||
12473 | // the values are the same. | |||
12474 | if (BuiltinOp == Builtin::BI__builtin_add_overflow || | |||
12475 | BuiltinOp == Builtin::BI__builtin_sub_overflow || | |||
12476 | BuiltinOp == Builtin::BI__builtin_mul_overflow) { | |||
12477 | // APSInt doesn't have a TruncOrSelf, so we use extOrTrunc instead, | |||
12478 | // since it will give us the behavior of a TruncOrSelf in the case where | |||
12479 | // its parameter <= its size. We previously set Result to be at least the | |||
12480 | // type-size of the result, so getTypeSize(ResultType) <= Result.BitWidth | |||
12481 | // will work exactly like TruncOrSelf. | |||
12482 | APSInt Temp = Result.extOrTrunc(Info.Ctx.getTypeSize(ResultType)); | |||
12483 | Temp.setIsSigned(ResultType->isSignedIntegerOrEnumerationType()); | |||
12484 | ||||
12485 | if (!APSInt::isSameValue(Temp, Result)) | |||
12486 | DidOverflow = true; | |||
12487 | Result = Temp; | |||
12488 | } | |||
12489 | ||||
12490 | APValue APV{Result}; | |||
12491 | if (!handleAssignment(Info, E, ResultLValue, ResultType, APV)) | |||
12492 | return false; | |||
12493 | return Success(DidOverflow, E); | |||
12494 | } | |||
12495 | } | |||
12496 | } | |||
12497 | ||||
12498 | /// Determine whether this is a pointer past the end of the complete | |||
12499 | /// object referred to by the lvalue. | |||
12500 | static bool isOnePastTheEndOfCompleteObject(const ASTContext &Ctx, | |||
12501 | const LValue &LV) { | |||
12502 | // A null pointer can be viewed as being "past the end" but we don't | |||
12503 | // choose to look at it that way here. | |||
12504 | if (!LV.getLValueBase()) | |||
12505 | return false; | |||
12506 | ||||
12507 | // If the designator is valid and refers to a subobject, we're not pointing | |||
12508 | // past the end. | |||
12509 | if (!LV.getLValueDesignator().Invalid && | |||
12510 | !LV.getLValueDesignator().isOnePastTheEnd()) | |||
12511 | return false; | |||
12512 | ||||
12513 | // A pointer to an incomplete type might be past-the-end if the type's size is | |||
12514 | // zero. We cannot tell because the type is incomplete. | |||
12515 | QualType Ty = getType(LV.getLValueBase()); | |||
12516 | if (Ty->isIncompleteType()) | |||
12517 | return true; | |||
12518 | ||||
12519 | // We're a past-the-end pointer if we point to the byte after the object, | |||
12520 | // no matter what our type or path is. | |||
12521 | auto Size = Ctx.getTypeSizeInChars(Ty); | |||
12522 | return LV.getLValueOffset() == Size; | |||
12523 | } | |||
12524 | ||||
12525 | namespace { | |||
12526 | ||||
12527 | /// Data recursive integer evaluator of certain binary operators. | |||
12528 | /// | |||
12529 | /// We use a data recursive algorithm for binary operators so that we are able | |||
12530 | /// to handle extreme cases of chained binary operators without causing stack | |||
12531 | /// overflow. | |||
12532 | class DataRecursiveIntBinOpEvaluator { | |||
12533 | struct EvalResult { | |||
12534 | APValue Val; | |||
12535 | bool Failed; | |||
12536 | ||||
12537 | EvalResult() : Failed(false) { } | |||
12538 | ||||
12539 | void swap(EvalResult &RHS) { | |||
12540 | Val.swap(RHS.Val); | |||
12541 | Failed = RHS.Failed; | |||
12542 | RHS.Failed = false; | |||
12543 | } | |||
12544 | }; | |||
12545 | ||||
12546 | struct Job { | |||
12547 | const Expr *E; | |||
12548 | EvalResult LHSResult; // meaningful only for binary operator expression. | |||
12549 | enum { AnyExprKind, BinOpKind, BinOpVisitedLHSKind } Kind; | |||
12550 | ||||
12551 | Job() = default; | |||
12552 | Job(Job &&) = default; | |||
12553 | ||||
12554 | void startSpeculativeEval(EvalInfo &Info) { | |||
12555 | SpecEvalRAII = SpeculativeEvaluationRAII(Info); | |||
12556 | } | |||
12557 | ||||
12558 | private: | |||
12559 | SpeculativeEvaluationRAII SpecEvalRAII; | |||
12560 | }; | |||
12561 | ||||
12562 | SmallVector<Job, 16> Queue; | |||
12563 | ||||
12564 | IntExprEvaluator &IntEval; | |||
12565 | EvalInfo &Info; | |||
12566 | APValue &FinalResult; | |||
12567 | ||||
12568 | public: | |||
12569 | DataRecursiveIntBinOpEvaluator(IntExprEvaluator &IntEval, APValue &Result) | |||
12570 | : IntEval(IntEval), Info(IntEval.getEvalInfo()), FinalResult(Result) { } | |||
12571 | ||||
12572 | /// True if \param E is a binary operator that we are going to handle | |||
12573 | /// data recursively. | |||
12574 | /// We handle binary operators that are comma, logical, or that have operands | |||
12575 | /// with integral or enumeration type. | |||
12576 | static bool shouldEnqueue(const BinaryOperator *E) { | |||
12577 | return E->getOpcode() == BO_Comma || E->isLogicalOp() || | |||
12578 | (E->isPRValue() && E->getType()->isIntegralOrEnumerationType() && | |||
12579 | E->getLHS()->getType()->isIntegralOrEnumerationType() && | |||
12580 | E->getRHS()->getType()->isIntegralOrEnumerationType()); | |||
12581 | } | |||
12582 | ||||
12583 | bool Traverse(const BinaryOperator *E) { | |||
12584 | enqueue(E); | |||
12585 | EvalResult PrevResult; | |||
12586 | while (!Queue.empty()) | |||
12587 | process(PrevResult); | |||
12588 | ||||
12589 | if (PrevResult.Failed) return false; | |||
12590 | ||||
12591 | FinalResult.swap(PrevResult.Val); | |||
12592 | return true; | |||
12593 | } | |||
12594 | ||||
12595 | private: | |||
12596 | bool Success(uint64_t Value, const Expr *E, APValue &Result) { | |||
12597 | return IntEval.Success(Value, E, Result); | |||
12598 | } | |||
12599 | bool Success(const APSInt &Value, const Expr *E, APValue &Result) { | |||
12600 | return IntEval.Success(Value, E, Result); | |||
12601 | } | |||
12602 | bool Error(const Expr *E) { | |||
12603 | return IntEval.Error(E); | |||
12604 | } | |||
12605 | bool Error(const Expr *E, diag::kind D) { | |||
12606 | return IntEval.Error(E, D); | |||
12607 | } | |||
12608 | ||||
12609 | OptionalDiagnostic CCEDiag(const Expr *E, diag::kind D) { | |||
12610 | return Info.CCEDiag(E, D); | |||
12611 | } | |||
12612 | ||||
12613 | // Returns true if visiting the RHS is necessary, false otherwise. | |||
12614 | bool VisitBinOpLHSOnly(EvalResult &LHSResult, const BinaryOperator *E, | |||
12615 | bool &SuppressRHSDiags); | |||
12616 | ||||
12617 | bool VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult, | |||
12618 | const BinaryOperator *E, APValue &Result); | |||
12619 | ||||
12620 | void EvaluateExpr(const Expr *E, EvalResult &Result) { | |||
12621 | Result.Failed = !Evaluate(Result.Val, Info, E); | |||
12622 | if (Result.Failed) | |||
12623 | Result.Val = APValue(); | |||
12624 | } | |||
12625 | ||||
12626 | void process(EvalResult &Result); | |||
12627 | ||||
12628 | void enqueue(const Expr *E) { | |||
12629 | E = E->IgnoreParens(); | |||
12630 | Queue.resize(Queue.size()+1); | |||
12631 | Queue.back().E = E; | |||
12632 | Queue.back().Kind = Job::AnyExprKind; | |||
12633 | } | |||
12634 | }; | |||
12635 | ||||
12636 | } | |||
12637 | ||||
12638 | bool DataRecursiveIntBinOpEvaluator:: | |||
12639 | VisitBinOpLHSOnly(EvalResult &LHSResult, const BinaryOperator *E, | |||
12640 | bool &SuppressRHSDiags) { | |||
12641 | if (E->getOpcode() == BO_Comma) { | |||
12642 | // Ignore LHS but note if we could not evaluate it. | |||
12643 | if (LHSResult.Failed) | |||
12644 | return Info.noteSideEffect(); | |||
12645 | return true; | |||
12646 | } | |||
12647 | ||||
12648 | if (E->isLogicalOp()) { | |||
12649 | bool LHSAsBool; | |||
12650 | if (!LHSResult.Failed && HandleConversionToBool(LHSResult.Val, LHSAsBool)) { | |||
12651 | // We were able to evaluate the LHS, see if we can get away with not | |||
12652 | // evaluating the RHS: 0 && X -> 0, 1 || X -> 1 | |||
12653 | if (LHSAsBool == (E->getOpcode() == BO_LOr)) { | |||
12654 | Success(LHSAsBool, E, LHSResult.Val); | |||
12655 | return false; // Ignore RHS | |||
12656 | } | |||
12657 | } else { | |||
12658 | LHSResult.Failed = true; | |||
12659 | ||||
12660 | // Since we weren't able to evaluate the left hand side, it | |||
12661 | // might have had side effects. | |||
12662 | if (!Info.noteSideEffect()) | |||
12663 | return false; | |||
12664 | ||||
12665 | // We can't evaluate the LHS; however, sometimes the result | |||
12666 | // is determined by the RHS: X && 0 -> 0, X || 1 -> 1. | |||
12667 | // Don't ignore RHS and suppress diagnostics from this arm. | |||
12668 | SuppressRHSDiags = true; | |||
12669 | } | |||
12670 | ||||
12671 | return true; | |||
12672 | } | |||
12673 | ||||
12674 | assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType () && E->getRHS()->getType()->isIntegralOrEnumerationType ()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()" , "clang/lib/AST/ExprConstant.cpp", 12675, __extension__ __PRETTY_FUNCTION__ )) | |||
12675 | E->getRHS()->getType()->isIntegralOrEnumerationType())(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType () && E->getRHS()->getType()->isIntegralOrEnumerationType ()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()" , "clang/lib/AST/ExprConstant.cpp", 12675, __extension__ __PRETTY_FUNCTION__ )); | |||
12676 | ||||
12677 | if (LHSResult.Failed && !Info.noteFailure()) | |||
12678 | return false; // Ignore RHS; | |||
12679 | ||||
12680 | return true; | |||
12681 | } | |||
12682 | ||||
12683 | static void addOrSubLValueAsInteger(APValue &LVal, const APSInt &Index, | |||
12684 | bool IsSub) { | |||
12685 | // Compute the new offset in the appropriate width, wrapping at 64 bits. | |||
12686 | // FIXME: When compiling for a 32-bit target, we should use 32-bit | |||
12687 | // offsets. | |||
12688 | assert(!LVal.hasLValuePath() && "have designator for integer lvalue")(static_cast <bool> (!LVal.hasLValuePath() && "have designator for integer lvalue" ) ? void (0) : __assert_fail ("!LVal.hasLValuePath() && \"have designator for integer lvalue\"" , "clang/lib/AST/ExprConstant.cpp", 12688, __extension__ __PRETTY_FUNCTION__ )); | |||
12689 | CharUnits &Offset = LVal.getLValueOffset(); | |||
12690 | uint64_t Offset64 = Offset.getQuantity(); | |||
12691 | uint64_t Index64 = Index.extOrTrunc(64).getZExtValue(); | |||
12692 | Offset = CharUnits::fromQuantity(IsSub ? Offset64 - Index64 | |||
12693 | : Offset64 + Index64); | |||
12694 | } | |||
12695 | ||||
12696 | bool DataRecursiveIntBinOpEvaluator:: | |||
12697 | VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult, | |||
12698 | const BinaryOperator *E, APValue &Result) { | |||
12699 | if (E->getOpcode() == BO_Comma) { | |||
12700 | if (RHSResult.Failed) | |||
12701 | return false; | |||
12702 | Result = RHSResult.Val; | |||
12703 | return true; | |||
12704 | } | |||
12705 | ||||
12706 | if (E->isLogicalOp()) { | |||
12707 | bool lhsResult, rhsResult; | |||
12708 | bool LHSIsOK = HandleConversionToBool(LHSResult.Val, lhsResult); | |||
12709 | bool RHSIsOK = HandleConversionToBool(RHSResult.Val, rhsResult); | |||
12710 | ||||
12711 | if (LHSIsOK) { | |||
12712 | if (RHSIsOK) { | |||
12713 | if (E->getOpcode() == BO_LOr) | |||
12714 | return Success(lhsResult || rhsResult, E, Result); | |||
12715 | else | |||
12716 | return Success(lhsResult && rhsResult, E, Result); | |||
12717 | } | |||
12718 | } else { | |||
12719 | if (RHSIsOK) { | |||
12720 | // We can't evaluate the LHS; however, sometimes the result | |||
12721 | // is determined by the RHS: X && 0 -> 0, X || 1 -> 1. | |||
12722 | if (rhsResult == (E->getOpcode() == BO_LOr)) | |||
12723 | return Success(rhsResult, E, Result); | |||
12724 | } | |||
12725 | } | |||
12726 | ||||
12727 | return false; | |||
12728 | } | |||
12729 | ||||
12730 | assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType () && E->getRHS()->getType()->isIntegralOrEnumerationType ()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()" , "clang/lib/AST/ExprConstant.cpp", 12731, __extension__ __PRETTY_FUNCTION__ )) | |||
12731 | E->getRHS()->getType()->isIntegralOrEnumerationType())(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType () && E->getRHS()->getType()->isIntegralOrEnumerationType ()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()" , "clang/lib/AST/ExprConstant.cpp", 12731, __extension__ __PRETTY_FUNCTION__ )); | |||
12732 | ||||
12733 | if (LHSResult.Failed || RHSResult.Failed) | |||
12734 | return false; | |||
12735 | ||||
12736 | const APValue &LHSVal = LHSResult.Val; | |||
12737 | const APValue &RHSVal = RHSResult.Val; | |||
12738 | ||||
12739 | // Handle cases like (unsigned long)&a + 4. | |||
12740 | if (E->isAdditiveOp() && LHSVal.isLValue() && RHSVal.isInt()) { | |||
12741 | Result = LHSVal; | |||
12742 | addOrSubLValueAsInteger(Result, RHSVal.getInt(), E->getOpcode() == BO_Sub); | |||
12743 | return true; | |||
12744 | } | |||
12745 | ||||
12746 | // Handle cases like 4 + (unsigned long)&a | |||
12747 | if (E->getOpcode() == BO_Add && | |||
12748 | RHSVal.isLValue() && LHSVal.isInt()) { | |||
12749 | Result = RHSVal; | |||
12750 | addOrSubLValueAsInteger(Result, LHSVal.getInt(), /*IsSub*/false); | |||
12751 | return true; | |||
12752 | } | |||
12753 | ||||
12754 | if (E->getOpcode() == BO_Sub && LHSVal.isLValue() && RHSVal.isLValue()) { | |||
12755 | // Handle (intptr_t)&&A - (intptr_t)&&B. | |||
12756 | if (!LHSVal.getLValueOffset().isZero() || | |||
12757 | !RHSVal.getLValueOffset().isZero()) | |||
12758 | return false; | |||
12759 | const Expr *LHSExpr = LHSVal.getLValueBase().dyn_cast<const Expr*>(); | |||
12760 | const Expr *RHSExpr = RHSVal.getLValueBase().dyn_cast<const Expr*>(); | |||
12761 | if (!LHSExpr || !RHSExpr) | |||
12762 | return false; | |||
12763 | const AddrLabelExpr *LHSAddrExpr = dyn_cast<AddrLabelExpr>(LHSExpr); | |||
12764 | const AddrLabelExpr *RHSAddrExpr = dyn_cast<AddrLabelExpr>(RHSExpr); | |||
12765 | if (!LHSAddrExpr || !RHSAddrExpr) | |||
12766 | return false; | |||
12767 | // Make sure both labels come from the same function. | |||
12768 | if (LHSAddrExpr->getLabel()->getDeclContext() != | |||
12769 | RHSAddrExpr->getLabel()->getDeclContext()) | |||
12770 | return false; | |||
12771 | Result = APValue(LHSAddrExpr, RHSAddrExpr); | |||
12772 | return true; | |||
12773 | } | |||
12774 | ||||
12775 | // All the remaining cases expect both operands to be an integer | |||
12776 | if (!LHSVal.isInt() || !RHSVal.isInt()) | |||
12777 | return Error(E); | |||
12778 | ||||
12779 | // Set up the width and signedness manually, in case it can't be deduced | |||
12780 | // from the operation we're performing. | |||
12781 | // FIXME: Don't do this in the cases where we can deduce it. | |||
12782 | APSInt Value(Info.Ctx.getIntWidth(E->getType()), | |||
12783 | E->getType()->isUnsignedIntegerOrEnumerationType()); | |||
12784 | if (!handleIntIntBinOp(Info, E, LHSVal.getInt(), E->getOpcode(), | |||
12785 | RHSVal.getInt(), Value)) | |||
12786 | return false; | |||
12787 | return Success(Value, E, Result); | |||
12788 | } | |||
12789 | ||||
12790 | void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) { | |||
12791 | Job &job = Queue.back(); | |||
12792 | ||||
12793 | switch (job.Kind) { | |||
12794 | case Job::AnyExprKind: { | |||
12795 | if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(job.E)) { | |||
12796 | if (shouldEnqueue(Bop)) { | |||
12797 | job.Kind = Job::BinOpKind; | |||
12798 | enqueue(Bop->getLHS()); | |||
12799 | return; | |||
12800 | } | |||
12801 | } | |||
12802 | ||||
12803 | EvaluateExpr(job.E, Result); | |||
12804 | Queue.pop_back(); | |||
12805 | return; | |||
12806 | } | |||
12807 | ||||
12808 | case Job::BinOpKind: { | |||
12809 | const BinaryOperator *Bop = cast<BinaryOperator>(job.E); | |||
12810 | bool SuppressRHSDiags = false; | |||
12811 | if (!VisitBinOpLHSOnly(Result, Bop, SuppressRHSDiags)) { | |||
12812 | Queue.pop_back(); | |||
12813 | return; | |||
12814 | } | |||
12815 | if (SuppressRHSDiags) | |||
12816 | job.startSpeculativeEval(Info); | |||
12817 | job.LHSResult.swap(Result); | |||
12818 | job.Kind = Job::BinOpVisitedLHSKind; | |||
12819 | enqueue(Bop->getRHS()); | |||
12820 | return; | |||
12821 | } | |||
12822 | ||||
12823 | case Job::BinOpVisitedLHSKind: { | |||
12824 | const BinaryOperator *Bop = cast<BinaryOperator>(job.E); | |||
12825 | EvalResult RHS; | |||
12826 | RHS.swap(Result); | |||
12827 | Result.Failed = !VisitBinOp(job.LHSResult, RHS, Bop, Result.Val); | |||
12828 | Queue.pop_back(); | |||
12829 | return; | |||
12830 | } | |||
12831 | } | |||
12832 | ||||
12833 | llvm_unreachable("Invalid Job::Kind!")::llvm::llvm_unreachable_internal("Invalid Job::Kind!", "clang/lib/AST/ExprConstant.cpp" , 12833); | |||
12834 | } | |||
12835 | ||||
12836 | namespace { | |||
12837 | enum class CmpResult { | |||
12838 | Unequal, | |||
12839 | Less, | |||
12840 | Equal, | |||
12841 | Greater, | |||
12842 | Unordered, | |||
12843 | }; | |||
12844 | } | |||
12845 | ||||
12846 | template <class SuccessCB, class AfterCB> | |||
12847 | static bool | |||
12848 | EvaluateComparisonBinaryOperator(EvalInfo &Info, const BinaryOperator *E, | |||
12849 | SuccessCB &&Success, AfterCB &&DoAfter) { | |||
12850 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 12850, __extension__ __PRETTY_FUNCTION__)); | |||
12851 | assert(E->isComparisonOp() && "expected comparison operator")(static_cast <bool> (E->isComparisonOp() && "expected comparison operator" ) ? void (0) : __assert_fail ("E->isComparisonOp() && \"expected comparison operator\"" , "clang/lib/AST/ExprConstant.cpp", 12851, __extension__ __PRETTY_FUNCTION__ )); | |||
12852 | assert((E->getOpcode() == BO_Cmp ||(static_cast <bool> ((E->getOpcode() == BO_Cmp || E-> getType()->isIntegralOrEnumerationType()) && "unsupported binary expression evaluation" ) ? void (0) : __assert_fail ("(E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\"" , "clang/lib/AST/ExprConstant.cpp", 12854, __extension__ __PRETTY_FUNCTION__ )) | |||
12853 | E->getType()->isIntegralOrEnumerationType()) &&(static_cast <bool> ((E->getOpcode() == BO_Cmp || E-> getType()->isIntegralOrEnumerationType()) && "unsupported binary expression evaluation" ) ? void (0) : __assert_fail ("(E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\"" , "clang/lib/AST/ExprConstant.cpp", 12854, __extension__ __PRETTY_FUNCTION__ )) | |||
12854 | "unsupported binary expression evaluation")(static_cast <bool> ((E->getOpcode() == BO_Cmp || E-> getType()->isIntegralOrEnumerationType()) && "unsupported binary expression evaluation" ) ? void (0) : __assert_fail ("(E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\"" , "clang/lib/AST/ExprConstant.cpp", 12854, __extension__ __PRETTY_FUNCTION__ )); | |||
12855 | auto Error = [&](const Expr *E) { | |||
12856 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
12857 | return false; | |||
12858 | }; | |||
12859 | ||||
12860 | bool IsRelational = E->isRelationalOp() || E->getOpcode() == BO_Cmp; | |||
12861 | bool IsEquality = E->isEqualityOp(); | |||
12862 | ||||
12863 | QualType LHSTy = E->getLHS()->getType(); | |||
12864 | QualType RHSTy = E->getRHS()->getType(); | |||
12865 | ||||
12866 | if (LHSTy->isIntegralOrEnumerationType() && | |||
12867 | RHSTy->isIntegralOrEnumerationType()) { | |||
12868 | APSInt LHS, RHS; | |||
12869 | bool LHSOK = EvaluateInteger(E->getLHS(), LHS, Info); | |||
12870 | if (!LHSOK && !Info.noteFailure()) | |||
12871 | return false; | |||
12872 | if (!EvaluateInteger(E->getRHS(), RHS, Info) || !LHSOK) | |||
12873 | return false; | |||
12874 | if (LHS < RHS) | |||
12875 | return Success(CmpResult::Less, E); | |||
12876 | if (LHS > RHS) | |||
12877 | return Success(CmpResult::Greater, E); | |||
12878 | return Success(CmpResult::Equal, E); | |||
12879 | } | |||
12880 | ||||
12881 | if (LHSTy->isFixedPointType() || RHSTy->isFixedPointType()) { | |||
12882 | APFixedPoint LHSFX(Info.Ctx.getFixedPointSemantics(LHSTy)); | |||
12883 | APFixedPoint RHSFX(Info.Ctx.getFixedPointSemantics(RHSTy)); | |||
12884 | ||||
12885 | bool LHSOK = EvaluateFixedPointOrInteger(E->getLHS(), LHSFX, Info); | |||
12886 | if (!LHSOK && !Info.noteFailure()) | |||
12887 | return false; | |||
12888 | if (!EvaluateFixedPointOrInteger(E->getRHS(), RHSFX, Info) || !LHSOK) | |||
12889 | return false; | |||
12890 | if (LHSFX < RHSFX) | |||
12891 | return Success(CmpResult::Less, E); | |||
12892 | if (LHSFX > RHSFX) | |||
12893 | return Success(CmpResult::Greater, E); | |||
12894 | return Success(CmpResult::Equal, E); | |||
12895 | } | |||
12896 | ||||
12897 | if (LHSTy->isAnyComplexType() || RHSTy->isAnyComplexType()) { | |||
12898 | ComplexValue LHS, RHS; | |||
12899 | bool LHSOK; | |||
12900 | if (E->isAssignmentOp()) { | |||
12901 | LValue LV; | |||
12902 | EvaluateLValue(E->getLHS(), LV, Info); | |||
12903 | LHSOK = false; | |||
12904 | } else if (LHSTy->isRealFloatingType()) { | |||
12905 | LHSOK = EvaluateFloat(E->getLHS(), LHS.FloatReal, Info); | |||
12906 | if (LHSOK) { | |||
12907 | LHS.makeComplexFloat(); | |||
12908 | LHS.FloatImag = APFloat(LHS.FloatReal.getSemantics()); | |||
12909 | } | |||
12910 | } else { | |||
12911 | LHSOK = EvaluateComplex(E->getLHS(), LHS, Info); | |||
12912 | } | |||
12913 | if (!LHSOK && !Info.noteFailure()) | |||
12914 | return false; | |||
12915 | ||||
12916 | if (E->getRHS()->getType()->isRealFloatingType()) { | |||
12917 | if (!EvaluateFloat(E->getRHS(), RHS.FloatReal, Info) || !LHSOK) | |||
12918 | return false; | |||
12919 | RHS.makeComplexFloat(); | |||
12920 | RHS.FloatImag = APFloat(RHS.FloatReal.getSemantics()); | |||
12921 | } else if (!EvaluateComplex(E->getRHS(), RHS, Info) || !LHSOK) | |||
12922 | return false; | |||
12923 | ||||
12924 | if (LHS.isComplexFloat()) { | |||
12925 | APFloat::cmpResult CR_r = | |||
12926 | LHS.getComplexFloatReal().compare(RHS.getComplexFloatReal()); | |||
12927 | APFloat::cmpResult CR_i = | |||
12928 | LHS.getComplexFloatImag().compare(RHS.getComplexFloatImag()); | |||
12929 | bool IsEqual = CR_r == APFloat::cmpEqual && CR_i == APFloat::cmpEqual; | |||
12930 | return Success(IsEqual ? CmpResult::Equal : CmpResult::Unequal, E); | |||
12931 | } else { | |||
12932 | assert(IsEquality && "invalid complex comparison")(static_cast <bool> (IsEquality && "invalid complex comparison" ) ? void (0) : __assert_fail ("IsEquality && \"invalid complex comparison\"" , "clang/lib/AST/ExprConstant.cpp", 12932, __extension__ __PRETTY_FUNCTION__ )); | |||
12933 | bool IsEqual = LHS.getComplexIntReal() == RHS.getComplexIntReal() && | |||
12934 | LHS.getComplexIntImag() == RHS.getComplexIntImag(); | |||
12935 | return Success(IsEqual ? CmpResult::Equal : CmpResult::Unequal, E); | |||
12936 | } | |||
12937 | } | |||
12938 | ||||
12939 | if (LHSTy->isRealFloatingType() && | |||
12940 | RHSTy->isRealFloatingType()) { | |||
12941 | APFloat RHS(0.0), LHS(0.0); | |||
12942 | ||||
12943 | bool LHSOK = EvaluateFloat(E->getRHS(), RHS, Info); | |||
12944 | if (!LHSOK && !Info.noteFailure()) | |||
12945 | return false; | |||
12946 | ||||
12947 | if (!EvaluateFloat(E->getLHS(), LHS, Info) || !LHSOK) | |||
12948 | return false; | |||
12949 | ||||
12950 | assert(E->isComparisonOp() && "Invalid binary operator!")(static_cast <bool> (E->isComparisonOp() && "Invalid binary operator!" ) ? void (0) : __assert_fail ("E->isComparisonOp() && \"Invalid binary operator!\"" , "clang/lib/AST/ExprConstant.cpp", 12950, __extension__ __PRETTY_FUNCTION__ )); | |||
12951 | llvm::APFloatBase::cmpResult APFloatCmpResult = LHS.compare(RHS); | |||
12952 | if (!Info.InConstantContext && | |||
12953 | APFloatCmpResult == APFloat::cmpUnordered && | |||
12954 | E->getFPFeaturesInEffect(Info.Ctx.getLangOpts()).isFPConstrained()) { | |||
12955 | // Note: Compares may raise invalid in some cases involving NaN or sNaN. | |||
12956 | Info.FFDiag(E, diag::note_constexpr_float_arithmetic_strict); | |||
12957 | return false; | |||
12958 | } | |||
12959 | auto GetCmpRes = [&]() { | |||
12960 | switch (APFloatCmpResult) { | |||
12961 | case APFloat::cmpEqual: | |||
12962 | return CmpResult::Equal; | |||
12963 | case APFloat::cmpLessThan: | |||
12964 | return CmpResult::Less; | |||
12965 | case APFloat::cmpGreaterThan: | |||
12966 | return CmpResult::Greater; | |||
12967 | case APFloat::cmpUnordered: | |||
12968 | return CmpResult::Unordered; | |||
12969 | } | |||
12970 | llvm_unreachable("Unrecognised APFloat::cmpResult enum")::llvm::llvm_unreachable_internal("Unrecognised APFloat::cmpResult enum" , "clang/lib/AST/ExprConstant.cpp", 12970); | |||
12971 | }; | |||
12972 | return Success(GetCmpRes(), E); | |||
12973 | } | |||
12974 | ||||
12975 | if (LHSTy->isPointerType() && RHSTy->isPointerType()) { | |||
12976 | LValue LHSValue, RHSValue; | |||
12977 | ||||
12978 | bool LHSOK = EvaluatePointer(E->getLHS(), LHSValue, Info); | |||
12979 | if (!LHSOK && !Info.noteFailure()) | |||
12980 | return false; | |||
12981 | ||||
12982 | if (!EvaluatePointer(E->getRHS(), RHSValue, Info) || !LHSOK) | |||
12983 | return false; | |||
12984 | ||||
12985 | // Reject differing bases from the normal codepath; we special-case | |||
12986 | // comparisons to null. | |||
12987 | if (!HasSameBase(LHSValue, RHSValue)) { | |||
12988 | auto DiagComparison = [&] (unsigned DiagID, bool Reversed = false) { | |||
12989 | std::string LHS = LHSValue.toString(Info.Ctx, E->getLHS()->getType()); | |||
12990 | std::string RHS = RHSValue.toString(Info.Ctx, E->getRHS()->getType()); | |||
12991 | Info.FFDiag(E, DiagID) | |||
12992 | << (Reversed ? RHS : LHS) << (Reversed ? LHS : RHS); | |||
12993 | return false; | |||
12994 | }; | |||
12995 | // Inequalities and subtractions between unrelated pointers have | |||
12996 | // unspecified or undefined behavior. | |||
12997 | if (!IsEquality) | |||
12998 | return DiagComparison( | |||
12999 | diag::note_constexpr_pointer_comparison_unspecified); | |||
13000 | // A constant address may compare equal to the address of a symbol. | |||
13001 | // The one exception is that address of an object cannot compare equal | |||
13002 | // to a null pointer constant. | |||
13003 | // TODO: Should we restrict this to actual null pointers, and exclude the | |||
13004 | // case of zero cast to pointer type? | |||
13005 | if ((!LHSValue.Base && !LHSValue.Offset.isZero()) || | |||
13006 | (!RHSValue.Base && !RHSValue.Offset.isZero())) | |||
13007 | return DiagComparison(diag::note_constexpr_pointer_constant_comparison, | |||
13008 | !RHSValue.Base); | |||
13009 | // It's implementation-defined whether distinct literals will have | |||
13010 | // distinct addresses. In clang, the result of such a comparison is | |||
13011 | // unspecified, so it is not a constant expression. However, we do know | |||
13012 | // that the address of a literal will be non-null. | |||
13013 | if ((IsLiteralLValue(LHSValue) || IsLiteralLValue(RHSValue)) && | |||
13014 | LHSValue.Base && RHSValue.Base) | |||
13015 | return DiagComparison(diag::note_constexpr_literal_comparison); | |||
13016 | // We can't tell whether weak symbols will end up pointing to the same | |||
13017 | // object. | |||
13018 | if (IsWeakLValue(LHSValue) || IsWeakLValue(RHSValue)) | |||
13019 | return DiagComparison(diag::note_constexpr_pointer_weak_comparison, | |||
13020 | !IsWeakLValue(LHSValue)); | |||
13021 | // We can't compare the address of the start of one object with the | |||
13022 | // past-the-end address of another object, per C++ DR1652. | |||
13023 | if (LHSValue.Base && LHSValue.Offset.isZero() && | |||
13024 | isOnePastTheEndOfCompleteObject(Info.Ctx, RHSValue)) | |||
13025 | return DiagComparison(diag::note_constexpr_pointer_comparison_past_end, | |||
13026 | true); | |||
13027 | if (RHSValue.Base && RHSValue.Offset.isZero() && | |||
13028 | isOnePastTheEndOfCompleteObject(Info.Ctx, LHSValue)) | |||
13029 | return DiagComparison(diag::note_constexpr_pointer_comparison_past_end, | |||
13030 | false); | |||
13031 | // We can't tell whether an object is at the same address as another | |||
13032 | // zero sized object. | |||
13033 | if ((RHSValue.Base && isZeroSized(LHSValue)) || | |||
13034 | (LHSValue.Base && isZeroSized(RHSValue))) | |||
13035 | return DiagComparison( | |||
13036 | diag::note_constexpr_pointer_comparison_zero_sized); | |||
13037 | return Success(CmpResult::Unequal, E); | |||
13038 | } | |||
13039 | ||||
13040 | const CharUnits &LHSOffset = LHSValue.getLValueOffset(); | |||
13041 | const CharUnits &RHSOffset = RHSValue.getLValueOffset(); | |||
13042 | ||||
13043 | SubobjectDesignator &LHSDesignator = LHSValue.getLValueDesignator(); | |||
13044 | SubobjectDesignator &RHSDesignator = RHSValue.getLValueDesignator(); | |||
13045 | ||||
13046 | // C++11 [expr.rel]p3: | |||
13047 | // Pointers to void (after pointer conversions) can be compared, with a | |||
13048 | // result defined as follows: If both pointers represent the same | |||
13049 | // address or are both the null pointer value, the result is true if the | |||
13050 | // operator is <= or >= and false otherwise; otherwise the result is | |||
13051 | // unspecified. | |||
13052 | // We interpret this as applying to pointers to *cv* void. | |||
13053 | if (LHSTy->isVoidPointerType() && LHSOffset != RHSOffset && IsRelational) | |||
13054 | Info.CCEDiag(E, diag::note_constexpr_void_comparison); | |||
13055 | ||||
13056 | // C++11 [expr.rel]p2: | |||
13057 | // - If two pointers point to non-static data members of the same object, | |||
13058 | // or to subobjects or array elements fo such members, recursively, the | |||
13059 | // pointer to the later declared member compares greater provided the | |||
13060 | // two members have the same access control and provided their class is | |||
13061 | // not a union. | |||
13062 | // [...] | |||
13063 | // - Otherwise pointer comparisons are unspecified. | |||
13064 | if (!LHSDesignator.Invalid && !RHSDesignator.Invalid && IsRelational) { | |||
13065 | bool WasArrayIndex; | |||
13066 | unsigned Mismatch = FindDesignatorMismatch( | |||
13067 | getType(LHSValue.Base), LHSDesignator, RHSDesignator, WasArrayIndex); | |||
13068 | // At the point where the designators diverge, the comparison has a | |||
13069 | // specified value if: | |||
13070 | // - we are comparing array indices | |||
13071 | // - we are comparing fields of a union, or fields with the same access | |||
13072 | // Otherwise, the result is unspecified and thus the comparison is not a | |||
13073 | // constant expression. | |||
13074 | if (!WasArrayIndex && Mismatch < LHSDesignator.Entries.size() && | |||
13075 | Mismatch < RHSDesignator.Entries.size()) { | |||
13076 | const FieldDecl *LF = getAsField(LHSDesignator.Entries[Mismatch]); | |||
13077 | const FieldDecl *RF = getAsField(RHSDesignator.Entries[Mismatch]); | |||
13078 | if (!LF && !RF) | |||
13079 | Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_classes); | |||
13080 | else if (!LF) | |||
13081 | Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_field) | |||
13082 | << getAsBaseClass(LHSDesignator.Entries[Mismatch]) | |||
13083 | << RF->getParent() << RF; | |||
13084 | else if (!RF) | |||
13085 | Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_field) | |||
13086 | << getAsBaseClass(RHSDesignator.Entries[Mismatch]) | |||
13087 | << LF->getParent() << LF; | |||
13088 | else if (!LF->getParent()->isUnion() && | |||
13089 | LF->getAccess() != RF->getAccess()) | |||
13090 | Info.CCEDiag(E, | |||
13091 | diag::note_constexpr_pointer_comparison_differing_access) | |||
13092 | << LF << LF->getAccess() << RF << RF->getAccess() | |||
13093 | << LF->getParent(); | |||
13094 | } | |||
13095 | } | |||
13096 | ||||
13097 | // The comparison here must be unsigned, and performed with the same | |||
13098 | // width as the pointer. | |||
13099 | unsigned PtrSize = Info.Ctx.getTypeSize(LHSTy); | |||
13100 | uint64_t CompareLHS = LHSOffset.getQuantity(); | |||
13101 | uint64_t CompareRHS = RHSOffset.getQuantity(); | |||
13102 | assert(PtrSize <= 64 && "Unexpected pointer width")(static_cast <bool> (PtrSize <= 64 && "Unexpected pointer width" ) ? void (0) : __assert_fail ("PtrSize <= 64 && \"Unexpected pointer width\"" , "clang/lib/AST/ExprConstant.cpp", 13102, __extension__ __PRETTY_FUNCTION__ )); | |||
13103 | uint64_t Mask = ~0ULL >> (64 - PtrSize); | |||
13104 | CompareLHS &= Mask; | |||
13105 | CompareRHS &= Mask; | |||
13106 | ||||
13107 | // If there is a base and this is a relational operator, we can only | |||
13108 | // compare pointers within the object in question; otherwise, the result | |||
13109 | // depends on where the object is located in memory. | |||
13110 | if (!LHSValue.Base.isNull() && IsRelational) { | |||
13111 | QualType BaseTy = getType(LHSValue.Base); | |||
13112 | if (BaseTy->isIncompleteType()) | |||
13113 | return Error(E); | |||
13114 | CharUnits Size = Info.Ctx.getTypeSizeInChars(BaseTy); | |||
13115 | uint64_t OffsetLimit = Size.getQuantity(); | |||
13116 | if (CompareLHS > OffsetLimit || CompareRHS > OffsetLimit) | |||
13117 | return Error(E); | |||
13118 | } | |||
13119 | ||||
13120 | if (CompareLHS < CompareRHS) | |||
13121 | return Success(CmpResult::Less, E); | |||
13122 | if (CompareLHS > CompareRHS) | |||
13123 | return Success(CmpResult::Greater, E); | |||
13124 | return Success(CmpResult::Equal, E); | |||
13125 | } | |||
13126 | ||||
13127 | if (LHSTy->isMemberPointerType()) { | |||
13128 | assert(IsEquality && "unexpected member pointer operation")(static_cast <bool> (IsEquality && "unexpected member pointer operation" ) ? void (0) : __assert_fail ("IsEquality && \"unexpected member pointer operation\"" , "clang/lib/AST/ExprConstant.cpp", 13128, __extension__ __PRETTY_FUNCTION__ )); | |||
13129 | assert(RHSTy->isMemberPointerType() && "invalid comparison")(static_cast <bool> (RHSTy->isMemberPointerType() && "invalid comparison") ? void (0) : __assert_fail ("RHSTy->isMemberPointerType() && \"invalid comparison\"" , "clang/lib/AST/ExprConstant.cpp", 13129, __extension__ __PRETTY_FUNCTION__ )); | |||
13130 | ||||
13131 | MemberPtr LHSValue, RHSValue; | |||
13132 | ||||
13133 | bool LHSOK = EvaluateMemberPointer(E->getLHS(), LHSValue, Info); | |||
13134 | if (!LHSOK && !Info.noteFailure()) | |||
13135 | return false; | |||
13136 | ||||
13137 | if (!EvaluateMemberPointer(E->getRHS(), RHSValue, Info) || !LHSOK) | |||
13138 | return false; | |||
13139 | ||||
13140 | // If either operand is a pointer to a weak function, the comparison is not | |||
13141 | // constant. | |||
13142 | if (LHSValue.getDecl() && LHSValue.getDecl()->isWeak()) { | |||
13143 | Info.FFDiag(E, diag::note_constexpr_mem_pointer_weak_comparison) | |||
13144 | << LHSValue.getDecl(); | |||
13145 | return false; | |||
13146 | } | |||
13147 | if (RHSValue.getDecl() && RHSValue.getDecl()->isWeak()) { | |||
13148 | Info.FFDiag(E, diag::note_constexpr_mem_pointer_weak_comparison) | |||
13149 | << RHSValue.getDecl(); | |||
13150 | return false; | |||
13151 | } | |||
13152 | ||||
13153 | // C++11 [expr.eq]p2: | |||
13154 | // If both operands are null, they compare equal. Otherwise if only one is | |||
13155 | // null, they compare unequal. | |||
13156 | if (!LHSValue.getDecl() || !RHSValue.getDecl()) { | |||
13157 | bool Equal = !LHSValue.getDecl() && !RHSValue.getDecl(); | |||
13158 | return Success(Equal ? CmpResult::Equal : CmpResult::Unequal, E); | |||
13159 | } | |||
13160 | ||||
13161 | // Otherwise if either is a pointer to a virtual member function, the | |||
13162 | // result is unspecified. | |||
13163 | if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(LHSValue.getDecl())) | |||
13164 | if (MD->isVirtual()) | |||
13165 | Info.CCEDiag(E, diag::note_constexpr_compare_virtual_mem_ptr) << MD; | |||
13166 | if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(RHSValue.getDecl())) | |||
13167 | if (MD->isVirtual()) | |||
13168 | Info.CCEDiag(E, diag::note_constexpr_compare_virtual_mem_ptr) << MD; | |||
13169 | ||||
13170 | // Otherwise they compare equal if and only if they would refer to the | |||
13171 | // same member of the same most derived object or the same subobject if | |||
13172 | // they were dereferenced with a hypothetical object of the associated | |||
13173 | // class type. | |||
13174 | bool Equal = LHSValue == RHSValue; | |||
13175 | return Success(Equal ? CmpResult::Equal : CmpResult::Unequal, E); | |||
13176 | } | |||
13177 | ||||
13178 | if (LHSTy->isNullPtrType()) { | |||
13179 | assert(E->isComparisonOp() && "unexpected nullptr operation")(static_cast <bool> (E->isComparisonOp() && "unexpected nullptr operation" ) ? void (0) : __assert_fail ("E->isComparisonOp() && \"unexpected nullptr operation\"" , "clang/lib/AST/ExprConstant.cpp", 13179, __extension__ __PRETTY_FUNCTION__ )); | |||
13180 | assert(RHSTy->isNullPtrType() && "missing pointer conversion")(static_cast <bool> (RHSTy->isNullPtrType() && "missing pointer conversion") ? void (0) : __assert_fail ("RHSTy->isNullPtrType() && \"missing pointer conversion\"" , "clang/lib/AST/ExprConstant.cpp", 13180, __extension__ __PRETTY_FUNCTION__ )); | |||
13181 | // C++11 [expr.rel]p4, [expr.eq]p3: If two operands of type std::nullptr_t | |||
13182 | // are compared, the result is true of the operator is <=, >= or ==, and | |||
13183 | // false otherwise. | |||
13184 | return Success(CmpResult::Equal, E); | |||
13185 | } | |||
13186 | ||||
13187 | return DoAfter(); | |||
13188 | } | |||
13189 | ||||
13190 | bool RecordExprEvaluator::VisitBinCmp(const BinaryOperator *E) { | |||
13191 | if (!CheckLiteralType(Info, E)) | |||
13192 | return false; | |||
13193 | ||||
13194 | auto OnSuccess = [&](CmpResult CR, const BinaryOperator *E) { | |||
13195 | ComparisonCategoryResult CCR; | |||
13196 | switch (CR) { | |||
13197 | case CmpResult::Unequal: | |||
13198 | llvm_unreachable("should never produce Unequal for three-way comparison")::llvm::llvm_unreachable_internal("should never produce Unequal for three-way comparison" , "clang/lib/AST/ExprConstant.cpp", 13198); | |||
13199 | case CmpResult::Less: | |||
13200 | CCR = ComparisonCategoryResult::Less; | |||
13201 | break; | |||
13202 | case CmpResult::Equal: | |||
13203 | CCR = ComparisonCategoryResult::Equal; | |||
13204 | break; | |||
13205 | case CmpResult::Greater: | |||
13206 | CCR = ComparisonCategoryResult::Greater; | |||
13207 | break; | |||
13208 | case CmpResult::Unordered: | |||
13209 | CCR = ComparisonCategoryResult::Unordered; | |||
13210 | break; | |||
13211 | } | |||
13212 | // Evaluation succeeded. Lookup the information for the comparison category | |||
13213 | // type and fetch the VarDecl for the result. | |||
13214 | const ComparisonCategoryInfo &CmpInfo = | |||
13215 | Info.Ctx.CompCategories.getInfoForType(E->getType()); | |||
13216 | const VarDecl *VD = CmpInfo.getValueInfo(CmpInfo.makeWeakResult(CCR))->VD; | |||
13217 | // Check and evaluate the result as a constant expression. | |||
13218 | LValue LV; | |||
13219 | LV.set(VD); | |||
13220 | if (!handleLValueToRValueConversion(Info, E, E->getType(), LV, Result)) | |||
13221 | return false; | |||
13222 | return CheckConstantExpression(Info, E->getExprLoc(), E->getType(), Result, | |||
13223 | ConstantExprKind::Normal); | |||
13224 | }; | |||
13225 | return EvaluateComparisonBinaryOperator(Info, E, OnSuccess, [&]() { | |||
13226 | return ExprEvaluatorBaseTy::VisitBinCmp(E); | |||
13227 | }); | |||
13228 | } | |||
13229 | ||||
13230 | bool RecordExprEvaluator::VisitCXXParenListInitExpr( | |||
13231 | const CXXParenListInitExpr *E) { | |||
13232 | return VisitCXXParenListOrInitListExpr(E, E->getInitExprs()); | |||
13233 | } | |||
13234 | ||||
13235 | bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
13236 | // We don't support assignment in C. C++ assignments don't get here because | |||
13237 | // assignment is an lvalue in C++. | |||
13238 | if (E->isAssignmentOp()) { | |||
13239 | Error(E); | |||
13240 | if (!Info.noteFailure()) | |||
13241 | return false; | |||
13242 | } | |||
13243 | ||||
13244 | if (DataRecursiveIntBinOpEvaluator::shouldEnqueue(E)) | |||
13245 | return DataRecursiveIntBinOpEvaluator(*this, Result).Traverse(E); | |||
13246 | ||||
13247 | assert((!E->getLHS()->getType()->isIntegralOrEnumerationType() ||(static_cast <bool> ((!E->getLHS()->getType()-> isIntegralOrEnumerationType() || !E->getRHS()->getType( )->isIntegralOrEnumerationType()) && "DataRecursiveIntBinOpEvaluator should have handled integral types" ) ? void (0) : __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() || !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\"" , "clang/lib/AST/ExprConstant.cpp", 13249, __extension__ __PRETTY_FUNCTION__ )) | |||
13248 | !E->getRHS()->getType()->isIntegralOrEnumerationType()) &&(static_cast <bool> ((!E->getLHS()->getType()-> isIntegralOrEnumerationType() || !E->getRHS()->getType( )->isIntegralOrEnumerationType()) && "DataRecursiveIntBinOpEvaluator should have handled integral types" ) ? void (0) : __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() || !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\"" , "clang/lib/AST/ExprConstant.cpp", 13249, __extension__ __PRETTY_FUNCTION__ )) | |||
13249 | "DataRecursiveIntBinOpEvaluator should have handled integral types")(static_cast <bool> ((!E->getLHS()->getType()-> isIntegralOrEnumerationType() || !E->getRHS()->getType( )->isIntegralOrEnumerationType()) && "DataRecursiveIntBinOpEvaluator should have handled integral types" ) ? void (0) : __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() || !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\"" , "clang/lib/AST/ExprConstant.cpp", 13249, __extension__ __PRETTY_FUNCTION__ )); | |||
13250 | ||||
13251 | if (E->isComparisonOp()) { | |||
13252 | // Evaluate builtin binary comparisons by evaluating them as three-way | |||
13253 | // comparisons and then translating the result. | |||
13254 | auto OnSuccess = [&](CmpResult CR, const BinaryOperator *E) { | |||
13255 | assert((CR != CmpResult::Unequal || E->isEqualityOp()) &&(static_cast <bool> ((CR != CmpResult::Unequal || E-> isEqualityOp()) && "should only produce Unequal for equality comparisons" ) ? void (0) : __assert_fail ("(CR != CmpResult::Unequal || E->isEqualityOp()) && \"should only produce Unequal for equality comparisons\"" , "clang/lib/AST/ExprConstant.cpp", 13256, __extension__ __PRETTY_FUNCTION__ )) | |||
13256 | "should only produce Unequal for equality comparisons")(static_cast <bool> ((CR != CmpResult::Unequal || E-> isEqualityOp()) && "should only produce Unequal for equality comparisons" ) ? void (0) : __assert_fail ("(CR != CmpResult::Unequal || E->isEqualityOp()) && \"should only produce Unequal for equality comparisons\"" , "clang/lib/AST/ExprConstant.cpp", 13256, __extension__ __PRETTY_FUNCTION__ )); | |||
13257 | bool IsEqual = CR == CmpResult::Equal, | |||
13258 | IsLess = CR == CmpResult::Less, | |||
13259 | IsGreater = CR == CmpResult::Greater; | |||
13260 | auto Op = E->getOpcode(); | |||
13261 | switch (Op) { | |||
13262 | default: | |||
13263 | llvm_unreachable("unsupported binary operator")::llvm::llvm_unreachable_internal("unsupported binary operator" , "clang/lib/AST/ExprConstant.cpp", 13263); | |||
13264 | case BO_EQ: | |||
13265 | case BO_NE: | |||
13266 | return Success(IsEqual == (Op == BO_EQ), E); | |||
13267 | case BO_LT: | |||
13268 | return Success(IsLess, E); | |||
13269 | case BO_GT: | |||
13270 | return Success(IsGreater, E); | |||
13271 | case BO_LE: | |||
13272 | return Success(IsEqual || IsLess, E); | |||
13273 | case BO_GE: | |||
13274 | return Success(IsEqual || IsGreater, E); | |||
13275 | } | |||
13276 | }; | |||
13277 | return EvaluateComparisonBinaryOperator(Info, E, OnSuccess, [&]() { | |||
13278 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
13279 | }); | |||
13280 | } | |||
13281 | ||||
13282 | QualType LHSTy = E->getLHS()->getType(); | |||
13283 | QualType RHSTy = E->getRHS()->getType(); | |||
13284 | ||||
13285 | if (LHSTy->isPointerType() && RHSTy->isPointerType() && | |||
13286 | E->getOpcode() == BO_Sub) { | |||
13287 | LValue LHSValue, RHSValue; | |||
13288 | ||||
13289 | bool LHSOK = EvaluatePointer(E->getLHS(), LHSValue, Info); | |||
13290 | if (!LHSOK && !Info.noteFailure()) | |||
13291 | return false; | |||
13292 | ||||
13293 | if (!EvaluatePointer(E->getRHS(), RHSValue, Info) || !LHSOK) | |||
13294 | return false; | |||
13295 | ||||
13296 | // Reject differing bases from the normal codepath; we special-case | |||
13297 | // comparisons to null. | |||
13298 | if (!HasSameBase(LHSValue, RHSValue)) { | |||
13299 | // Handle &&A - &&B. | |||
13300 | if (!LHSValue.Offset.isZero() || !RHSValue.Offset.isZero()) | |||
13301 | return Error(E); | |||
13302 | const Expr *LHSExpr = LHSValue.Base.dyn_cast<const Expr *>(); | |||
13303 | const Expr *RHSExpr = RHSValue.Base.dyn_cast<const Expr *>(); | |||
13304 | if (!LHSExpr || !RHSExpr) | |||
13305 | return Error(E); | |||
13306 | const AddrLabelExpr *LHSAddrExpr = dyn_cast<AddrLabelExpr>(LHSExpr); | |||
13307 | const AddrLabelExpr *RHSAddrExpr = dyn_cast<AddrLabelExpr>(RHSExpr); | |||
13308 | if (!LHSAddrExpr || !RHSAddrExpr) | |||
13309 | return Error(E); | |||
13310 | // Make sure both labels come from the same function. | |||
13311 | if (LHSAddrExpr->getLabel()->getDeclContext() != | |||
13312 | RHSAddrExpr->getLabel()->getDeclContext()) | |||
13313 | return Error(E); | |||
13314 | return Success(APValue(LHSAddrExpr, RHSAddrExpr), E); | |||
13315 | } | |||
13316 | const CharUnits &LHSOffset = LHSValue.getLValueOffset(); | |||
13317 | const CharUnits &RHSOffset = RHSValue.getLValueOffset(); | |||
13318 | ||||
13319 | SubobjectDesignator &LHSDesignator = LHSValue.getLValueDesignator(); | |||
13320 | SubobjectDesignator &RHSDesignator = RHSValue.getLValueDesignator(); | |||
13321 | ||||
13322 | // C++11 [expr.add]p6: | |||
13323 | // Unless both pointers point to elements of the same array object, or | |||
13324 | // one past the last element of the array object, the behavior is | |||
13325 | // undefined. | |||
13326 | if (!LHSDesignator.Invalid && !RHSDesignator.Invalid && | |||
13327 | !AreElementsOfSameArray(getType(LHSValue.Base), LHSDesignator, | |||
13328 | RHSDesignator)) | |||
13329 | Info.CCEDiag(E, diag::note_constexpr_pointer_subtraction_not_same_array); | |||
13330 | ||||
13331 | QualType Type = E->getLHS()->getType(); | |||
13332 | QualType ElementType = Type->castAs<PointerType>()->getPointeeType(); | |||
13333 | ||||
13334 | CharUnits ElementSize; | |||
13335 | if (!HandleSizeof(Info, E->getExprLoc(), ElementType, ElementSize)) | |||
13336 | return false; | |||
13337 | ||||
13338 | // As an extension, a type may have zero size (empty struct or union in | |||
13339 | // C, array of zero length). Pointer subtraction in such cases has | |||
13340 | // undefined behavior, so is not constant. | |||
13341 | if (ElementSize.isZero()) { | |||
13342 | Info.FFDiag(E, diag::note_constexpr_pointer_subtraction_zero_size) | |||
13343 | << ElementType; | |||
13344 | return false; | |||
13345 | } | |||
13346 | ||||
13347 | // FIXME: LLVM and GCC both compute LHSOffset - RHSOffset at runtime, | |||
13348 | // and produce incorrect results when it overflows. Such behavior | |||
13349 | // appears to be non-conforming, but is common, so perhaps we should | |||
13350 | // assume the standard intended for such cases to be undefined behavior | |||
13351 | // and check for them. | |||
13352 | ||||
13353 | // Compute (LHSOffset - RHSOffset) / Size carefully, checking for | |||
13354 | // overflow in the final conversion to ptrdiff_t. | |||
13355 | APSInt LHS(llvm::APInt(65, (int64_t)LHSOffset.getQuantity(), true), false); | |||
13356 | APSInt RHS(llvm::APInt(65, (int64_t)RHSOffset.getQuantity(), true), false); | |||
13357 | APSInt ElemSize(llvm::APInt(65, (int64_t)ElementSize.getQuantity(), true), | |||
13358 | false); | |||
13359 | APSInt TrueResult = (LHS - RHS) / ElemSize; | |||
13360 | APSInt Result = TrueResult.trunc(Info.Ctx.getIntWidth(E->getType())); | |||
13361 | ||||
13362 | if (Result.extend(65) != TrueResult && | |||
13363 | !HandleOverflow(Info, E, TrueResult, E->getType())) | |||
13364 | return false; | |||
13365 | return Success(Result, E); | |||
13366 | } | |||
13367 | ||||
13368 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
13369 | } | |||
13370 | ||||
13371 | /// VisitUnaryExprOrTypeTraitExpr - Evaluate a sizeof, alignof or vec_step with | |||
13372 | /// a result as the expression's type. | |||
13373 | bool IntExprEvaluator::VisitUnaryExprOrTypeTraitExpr( | |||
13374 | const UnaryExprOrTypeTraitExpr *E) { | |||
13375 | switch(E->getKind()) { | |||
13376 | case UETT_PreferredAlignOf: | |||
13377 | case UETT_AlignOf: { | |||
13378 | if (E->isArgumentType()) | |||
13379 | return Success(GetAlignOfType(Info, E->getArgumentType(), E->getKind()), | |||
13380 | E); | |||
13381 | else | |||
13382 | return Success(GetAlignOfExpr(Info, E->getArgumentExpr(), E->getKind()), | |||
13383 | E); | |||
13384 | } | |||
13385 | ||||
13386 | case UETT_VecStep: { | |||
13387 | QualType Ty = E->getTypeOfArgument(); | |||
13388 | ||||
13389 | if (Ty->isVectorType()) { | |||
13390 | unsigned n = Ty->castAs<VectorType>()->getNumElements(); | |||
13391 | ||||
13392 | // The vec_step built-in functions that take a 3-component | |||
13393 | // vector return 4. (OpenCL 1.1 spec 6.11.12) | |||
13394 | if (n == 3) | |||
13395 | n = 4; | |||
13396 | ||||
13397 | return Success(n, E); | |||
13398 | } else | |||
13399 | return Success(1, E); | |||
13400 | } | |||
13401 | ||||
13402 | case UETT_SizeOf: { | |||
13403 | QualType SrcTy = E->getTypeOfArgument(); | |||
13404 | // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, | |||
13405 | // the result is the size of the referenced type." | |||
13406 | if (const ReferenceType *Ref = SrcTy->getAs<ReferenceType>()) | |||
13407 | SrcTy = Ref->getPointeeType(); | |||
13408 | ||||
13409 | CharUnits Sizeof; | |||
13410 | if (!HandleSizeof(Info, E->getExprLoc(), SrcTy, Sizeof)) | |||
13411 | return false; | |||
13412 | return Success(Sizeof, E); | |||
13413 | } | |||
13414 | case UETT_OpenMPRequiredSimdAlign: | |||
13415 | assert(E->isArgumentType())(static_cast <bool> (E->isArgumentType()) ? void (0) : __assert_fail ("E->isArgumentType()", "clang/lib/AST/ExprConstant.cpp" , 13415, __extension__ __PRETTY_FUNCTION__)); | |||
13416 | return Success( | |||
13417 | Info.Ctx.toCharUnitsFromBits( | |||
13418 | Info.Ctx.getOpenMPDefaultSimdAlign(E->getArgumentType())) | |||
13419 | .getQuantity(), | |||
13420 | E); | |||
13421 | } | |||
13422 | ||||
13423 | llvm_unreachable("unknown expr/type trait")::llvm::llvm_unreachable_internal("unknown expr/type trait", "clang/lib/AST/ExprConstant.cpp" , 13423); | |||
13424 | } | |||
13425 | ||||
13426 | bool IntExprEvaluator::VisitOffsetOfExpr(const OffsetOfExpr *OOE) { | |||
13427 | CharUnits Result; | |||
13428 | unsigned n = OOE->getNumComponents(); | |||
13429 | if (n == 0) | |||
13430 | return Error(OOE); | |||
13431 | QualType CurrentType = OOE->getTypeSourceInfo()->getType(); | |||
13432 | for (unsigned i = 0; i != n; ++i) { | |||
13433 | OffsetOfNode ON = OOE->getComponent(i); | |||
13434 | switch (ON.getKind()) { | |||
13435 | case OffsetOfNode::Array: { | |||
13436 | const Expr *Idx = OOE->getIndexExpr(ON.getArrayExprIndex()); | |||
13437 | APSInt IdxResult; | |||
13438 | if (!EvaluateInteger(Idx, IdxResult, Info)) | |||
13439 | return false; | |||
13440 | const ArrayType *AT = Info.Ctx.getAsArrayType(CurrentType); | |||
13441 | if (!AT) | |||
13442 | return Error(OOE); | |||
13443 | CurrentType = AT->getElementType(); | |||
13444 | CharUnits ElementSize = Info.Ctx.getTypeSizeInChars(CurrentType); | |||
13445 | Result += IdxResult.getSExtValue() * ElementSize; | |||
13446 | break; | |||
13447 | } | |||
13448 | ||||
13449 | case OffsetOfNode::Field: { | |||
13450 | FieldDecl *MemberDecl = ON.getField(); | |||
13451 | const RecordType *RT = CurrentType->getAs<RecordType>(); | |||
13452 | if (!RT) | |||
13453 | return Error(OOE); | |||
13454 | RecordDecl *RD = RT->getDecl(); | |||
13455 | if (RD->isInvalidDecl()) return false; | |||
13456 | const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD); | |||
13457 | unsigned i = MemberDecl->getFieldIndex(); | |||
13458 | assert(i < RL.getFieldCount() && "offsetof field in wrong type")(static_cast <bool> (i < RL.getFieldCount() && "offsetof field in wrong type") ? void (0) : __assert_fail ( "i < RL.getFieldCount() && \"offsetof field in wrong type\"" , "clang/lib/AST/ExprConstant.cpp", 13458, __extension__ __PRETTY_FUNCTION__ )); | |||
13459 | Result += Info.Ctx.toCharUnitsFromBits(RL.getFieldOffset(i)); | |||
13460 | CurrentType = MemberDecl->getType().getNonReferenceType(); | |||
13461 | break; | |||
13462 | } | |||
13463 | ||||
13464 | case OffsetOfNode::Identifier: | |||
13465 | llvm_unreachable("dependent __builtin_offsetof")::llvm::llvm_unreachable_internal("dependent __builtin_offsetof" , "clang/lib/AST/ExprConstant.cpp", 13465); | |||
13466 | ||||
13467 | case OffsetOfNode::Base: { | |||
13468 | CXXBaseSpecifier *BaseSpec = ON.getBase(); | |||
13469 | if (BaseSpec->isVirtual()) | |||
13470 | return Error(OOE); | |||
13471 | ||||
13472 | // Find the layout of the class whose base we are looking into. | |||
13473 | const RecordType *RT = CurrentType->getAs<RecordType>(); | |||
13474 | if (!RT) | |||
13475 | return Error(OOE); | |||
13476 | RecordDecl *RD = RT->getDecl(); | |||
13477 | if (RD->isInvalidDecl()) return false; | |||
13478 | const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD); | |||
13479 | ||||
13480 | // Find the base class itself. | |||
13481 | CurrentType = BaseSpec->getType(); | |||
13482 | const RecordType *BaseRT = CurrentType->getAs<RecordType>(); | |||
13483 | if (!BaseRT) | |||
13484 | return Error(OOE); | |||
13485 | ||||
13486 | // Add the offset to the base. | |||
13487 | Result += RL.getBaseClassOffset(cast<CXXRecordDecl>(BaseRT->getDecl())); | |||
13488 | break; | |||
13489 | } | |||
13490 | } | |||
13491 | } | |||
13492 | return Success(Result, OOE); | |||
13493 | } | |||
13494 | ||||
13495 | bool IntExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { | |||
13496 | switch (E->getOpcode()) { | |||
13497 | default: | |||
13498 | // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. | |||
13499 | // See C99 6.6p3. | |||
13500 | return Error(E); | |||
13501 | case UO_Extension: | |||
13502 | // FIXME: Should extension allow i-c-e extension expressions in its scope? | |||
13503 | // If so, we could clear the diagnostic ID. | |||
13504 | return Visit(E->getSubExpr()); | |||
13505 | case UO_Plus: | |||
13506 | // The result is just the value. | |||
13507 | return Visit(E->getSubExpr()); | |||
13508 | case UO_Minus: { | |||
13509 | if (!Visit(E->getSubExpr())) | |||
13510 | return false; | |||
13511 | if (!Result.isInt()) return Error(E); | |||
13512 | const APSInt &Value = Result.getInt(); | |||
13513 | if (Value.isSigned() && Value.isMinSignedValue() && E->canOverflow()) { | |||
13514 | if (Info.checkingForUndefinedBehavior()) | |||
13515 | Info.Ctx.getDiagnostics().Report(E->getExprLoc(), | |||
13516 | diag::warn_integer_constant_overflow) | |||
13517 | << toString(Value, 10) << E->getType(); | |||
13518 | ||||
13519 | if (!HandleOverflow(Info, E, -Value.extend(Value.getBitWidth() + 1), | |||
13520 | E->getType())) | |||
13521 | return false; | |||
13522 | } | |||
13523 | return Success(-Value, E); | |||
13524 | } | |||
13525 | case UO_Not: { | |||
13526 | if (!Visit(E->getSubExpr())) | |||
13527 | return false; | |||
13528 | if (!Result.isInt()) return Error(E); | |||
13529 | return Success(~Result.getInt(), E); | |||
13530 | } | |||
13531 | case UO_LNot: { | |||
13532 | bool bres; | |||
13533 | if (!EvaluateAsBooleanCondition(E->getSubExpr(), bres, Info)) | |||
13534 | return false; | |||
13535 | return Success(!bres, E); | |||
13536 | } | |||
13537 | } | |||
13538 | } | |||
13539 | ||||
13540 | /// HandleCast - This is used to evaluate implicit or explicit casts where the | |||
13541 | /// result type is integer. | |||
13542 | bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
13543 | const Expr *SubExpr = E->getSubExpr(); | |||
13544 | QualType DestType = E->getType(); | |||
13545 | QualType SrcType = SubExpr->getType(); | |||
13546 | ||||
13547 | switch (E->getCastKind()) { | |||
13548 | case CK_BaseToDerived: | |||
13549 | case CK_DerivedToBase: | |||
13550 | case CK_UncheckedDerivedToBase: | |||
13551 | case CK_Dynamic: | |||
13552 | case CK_ToUnion: | |||
13553 | case CK_ArrayToPointerDecay: | |||
13554 | case CK_FunctionToPointerDecay: | |||
13555 | case CK_NullToPointer: | |||
13556 | case CK_NullToMemberPointer: | |||
13557 | case CK_BaseToDerivedMemberPointer: | |||
13558 | case CK_DerivedToBaseMemberPointer: | |||
13559 | case CK_ReinterpretMemberPointer: | |||
13560 | case CK_ConstructorConversion: | |||
13561 | case CK_IntegralToPointer: | |||
13562 | case CK_ToVoid: | |||
13563 | case CK_VectorSplat: | |||
13564 | case CK_IntegralToFloating: | |||
13565 | case CK_FloatingCast: | |||
13566 | case CK_CPointerToObjCPointerCast: | |||
13567 | case CK_BlockPointerToObjCPointerCast: | |||
13568 | case CK_AnyPointerToBlockPointerCast: | |||
13569 | case CK_ObjCObjectLValueCast: | |||
13570 | case CK_FloatingRealToComplex: | |||
13571 | case CK_FloatingComplexToReal: | |||
13572 | case CK_FloatingComplexCast: | |||
13573 | case CK_FloatingComplexToIntegralComplex: | |||
13574 | case CK_IntegralRealToComplex: | |||
13575 | case CK_IntegralComplexCast: | |||
13576 | case CK_IntegralComplexToFloatingComplex: | |||
13577 | case CK_BuiltinFnToFnPtr: | |||
13578 | case CK_ZeroToOCLOpaqueType: | |||
13579 | case CK_NonAtomicToAtomic: | |||
13580 | case CK_AddressSpaceConversion: | |||
13581 | case CK_IntToOCLSampler: | |||
13582 | case CK_FloatingToFixedPoint: | |||
13583 | case CK_FixedPointToFloating: | |||
13584 | case CK_FixedPointCast: | |||
13585 | case CK_IntegralToFixedPoint: | |||
13586 | case CK_MatrixCast: | |||
13587 | llvm_unreachable("invalid cast kind for integral value")::llvm::llvm_unreachable_internal("invalid cast kind for integral value" , "clang/lib/AST/ExprConstant.cpp", 13587); | |||
13588 | ||||
13589 | case CK_BitCast: | |||
13590 | case CK_Dependent: | |||
13591 | case CK_LValueBitCast: | |||
13592 | case CK_ARCProduceObject: | |||
13593 | case CK_ARCConsumeObject: | |||
13594 | case CK_ARCReclaimReturnedObject: | |||
13595 | case CK_ARCExtendBlockObject: | |||
13596 | case CK_CopyAndAutoreleaseBlockObject: | |||
13597 | return Error(E); | |||
13598 | ||||
13599 | case CK_UserDefinedConversion: | |||
13600 | case CK_LValueToRValue: | |||
13601 | case CK_AtomicToNonAtomic: | |||
13602 | case CK_NoOp: | |||
13603 | case CK_LValueToRValueBitCast: | |||
13604 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
13605 | ||||
13606 | case CK_MemberPointerToBoolean: | |||
13607 | case CK_PointerToBoolean: | |||
13608 | case CK_IntegralToBoolean: | |||
13609 | case CK_FloatingToBoolean: | |||
13610 | case CK_BooleanToSignedIntegral: | |||
13611 | case CK_FloatingComplexToBoolean: | |||
13612 | case CK_IntegralComplexToBoolean: { | |||
13613 | bool BoolResult; | |||
13614 | if (!EvaluateAsBooleanCondition(SubExpr, BoolResult, Info)) | |||
13615 | return false; | |||
13616 | uint64_t IntResult = BoolResult; | |||
13617 | if (BoolResult && E->getCastKind() == CK_BooleanToSignedIntegral) | |||
13618 | IntResult = (uint64_t)-1; | |||
13619 | return Success(IntResult, E); | |||
13620 | } | |||
13621 | ||||
13622 | case CK_FixedPointToIntegral: { | |||
13623 | APFixedPoint Src(Info.Ctx.getFixedPointSemantics(SrcType)); | |||
13624 | if (!EvaluateFixedPoint(SubExpr, Src, Info)) | |||
13625 | return false; | |||
13626 | bool Overflowed; | |||
13627 | llvm::APSInt Result = Src.convertToInt( | |||
13628 | Info.Ctx.getIntWidth(DestType), | |||
13629 | DestType->isSignedIntegerOrEnumerationType(), &Overflowed); | |||
13630 | if (Overflowed && !HandleOverflow(Info, E, Result, DestType)) | |||
13631 | return false; | |||
13632 | return Success(Result, E); | |||
13633 | } | |||
13634 | ||||
13635 | case CK_FixedPointToBoolean: { | |||
13636 | // Unsigned padding does not affect this. | |||
13637 | APValue Val; | |||
13638 | if (!Evaluate(Val, Info, SubExpr)) | |||
13639 | return false; | |||
13640 | return Success(Val.getFixedPoint().getBoolValue(), E); | |||
13641 | } | |||
13642 | ||||
13643 | case CK_IntegralCast: { | |||
13644 | if (!Visit(SubExpr)) | |||
13645 | return false; | |||
13646 | ||||
13647 | if (!Result.isInt()) { | |||
13648 | // Allow casts of address-of-label differences if they are no-ops | |||
13649 | // or narrowing. (The narrowing case isn't actually guaranteed to | |||
13650 | // be constant-evaluatable except in some narrow cases which are hard | |||
13651 | // to detect here. We let it through on the assumption the user knows | |||
13652 | // what they are doing.) | |||
13653 | if (Result.isAddrLabelDiff()) | |||
13654 | return Info.Ctx.getTypeSize(DestType) <= Info.Ctx.getTypeSize(SrcType); | |||
13655 | // Only allow casts of lvalues if they are lossless. | |||
13656 | return Info.Ctx.getTypeSize(DestType) == Info.Ctx.getTypeSize(SrcType); | |||
13657 | } | |||
13658 | ||||
13659 | if (Info.Ctx.getLangOpts().CPlusPlus && Info.InConstantContext && | |||
13660 | Info.EvalMode == EvalInfo::EM_ConstantExpression && | |||
13661 | DestType->isEnumeralType()) { | |||
13662 | ||||
13663 | bool ConstexprVar = true; | |||
13664 | ||||
13665 | // We know if we are here that we are in a context that we might require | |||
13666 | // a constant expression or a context that requires a constant | |||
13667 | // value. But if we are initializing a value we don't know if it is a | |||
13668 | // constexpr variable or not. We can check the EvaluatingDecl to determine | |||
13669 | // if it constexpr or not. If not then we don't want to emit a diagnostic. | |||
13670 | if (const auto *VD = dyn_cast_or_null<VarDecl>( | |||
13671 | Info.EvaluatingDecl.dyn_cast<const ValueDecl *>())) | |||
13672 | ConstexprVar = VD->isConstexpr(); | |||
13673 | ||||
13674 | const EnumType *ET = dyn_cast<EnumType>(DestType.getCanonicalType()); | |||
13675 | const EnumDecl *ED = ET->getDecl(); | |||
13676 | // Check that the value is within the range of the enumeration values. | |||
13677 | // | |||
13678 | // This corressponds to [expr.static.cast]p10 which says: | |||
13679 | // A value of integral or enumeration type can be explicitly converted | |||
13680 | // to a complete enumeration type ... If the enumeration type does not | |||
13681 | // have a fixed underlying type, the value is unchanged if the original | |||
13682 | // value is within the range of the enumeration values ([dcl.enum]), and | |||
13683 | // otherwise, the behavior is undefined. | |||
13684 | // | |||
13685 | // This was resolved as part of DR2338 which has CD5 status. | |||
13686 | if (!ED->isFixed()) { | |||
13687 | llvm::APInt Min; | |||
13688 | llvm::APInt Max; | |||
13689 | ||||
13690 | ED->getValueRange(Max, Min); | |||
13691 | --Max; | |||
13692 | ||||
13693 | if (ED->getNumNegativeBits() && ConstexprVar && | |||
13694 | (Max.slt(Result.getInt().getSExtValue()) || | |||
13695 | Min.sgt(Result.getInt().getSExtValue()))) | |||
13696 | Info.Ctx.getDiagnostics().Report( | |||
13697 | E->getExprLoc(), diag::warn_constexpr_unscoped_enum_out_of_range) | |||
13698 | << llvm::toString(Result.getInt(), 10) << Min.getSExtValue() | |||
13699 | << Max.getSExtValue(); | |||
13700 | else if (!ED->getNumNegativeBits() && ConstexprVar && | |||
13701 | Max.ult(Result.getInt().getZExtValue())) | |||
13702 | Info.Ctx.getDiagnostics().Report(E->getExprLoc(), | |||
13703 | diag::warn_constexpr_unscoped_enum_out_of_range) | |||
13704 | << llvm::toString(Result.getInt(),10) << Min.getZExtValue() << Max.getZExtValue(); | |||
13705 | } | |||
13706 | } | |||
13707 | ||||
13708 | return Success(HandleIntToIntCast(Info, E, DestType, SrcType, | |||
13709 | Result.getInt()), E); | |||
13710 | } | |||
13711 | ||||
13712 | case CK_PointerToIntegral: { | |||
13713 | CCEDiag(E, diag::note_constexpr_invalid_cast) | |||
13714 | << 2 << Info.Ctx.getLangOpts().CPlusPlus; | |||
13715 | ||||
13716 | LValue LV; | |||
13717 | if (!EvaluatePointer(SubExpr, LV, Info)) | |||
13718 | return false; | |||
13719 | ||||
13720 | if (LV.getLValueBase()) { | |||
13721 | // Only allow based lvalue casts if they are lossless. | |||
13722 | // FIXME: Allow a larger integer size than the pointer size, and allow | |||
13723 | // narrowing back down to pointer width in subsequent integral casts. | |||
13724 | // FIXME: Check integer type's active bits, not its type size. | |||
13725 | if (Info.Ctx.getTypeSize(DestType) != Info.Ctx.getTypeSize(SrcType)) | |||
13726 | return Error(E); | |||
13727 | ||||
13728 | LV.Designator.setInvalid(); | |||
13729 | LV.moveInto(Result); | |||
13730 | return true; | |||
13731 | } | |||
13732 | ||||
13733 | APSInt AsInt; | |||
13734 | APValue V; | |||
13735 | LV.moveInto(V); | |||
13736 | if (!V.toIntegralConstant(AsInt, SrcType, Info.Ctx)) | |||
13737 | llvm_unreachable("Can't cast this!")::llvm::llvm_unreachable_internal("Can't cast this!", "clang/lib/AST/ExprConstant.cpp" , 13737); | |||
13738 | ||||
13739 | return Success(HandleIntToIntCast(Info, E, DestType, SrcType, AsInt), E); | |||
13740 | } | |||
13741 | ||||
13742 | case CK_IntegralComplexToReal: { | |||
13743 | ComplexValue C; | |||
13744 | if (!EvaluateComplex(SubExpr, C, Info)) | |||
13745 | return false; | |||
13746 | return Success(C.getComplexIntReal(), E); | |||
13747 | } | |||
13748 | ||||
13749 | case CK_FloatingToIntegral: { | |||
13750 | APFloat F(0.0); | |||
13751 | if (!EvaluateFloat(SubExpr, F, Info)) | |||
13752 | return false; | |||
13753 | ||||
13754 | APSInt Value; | |||
13755 | if (!HandleFloatToIntCast(Info, E, SrcType, F, DestType, Value)) | |||
13756 | return false; | |||
13757 | return Success(Value, E); | |||
13758 | } | |||
13759 | } | |||
13760 | ||||
13761 | llvm_unreachable("unknown cast resulting in integral value")::llvm::llvm_unreachable_internal("unknown cast resulting in integral value" , "clang/lib/AST/ExprConstant.cpp", 13761); | |||
13762 | } | |||
13763 | ||||
13764 | bool IntExprEvaluator::VisitUnaryReal(const UnaryOperator *E) { | |||
13765 | if (E->getSubExpr()->getType()->isAnyComplexType()) { | |||
13766 | ComplexValue LV; | |||
13767 | if (!EvaluateComplex(E->getSubExpr(), LV, Info)) | |||
13768 | return false; | |||
13769 | if (!LV.isComplexInt()) | |||
13770 | return Error(E); | |||
13771 | return Success(LV.getComplexIntReal(), E); | |||
13772 | } | |||
13773 | ||||
13774 | return Visit(E->getSubExpr()); | |||
13775 | } | |||
13776 | ||||
13777 | bool IntExprEvaluator::VisitUnaryImag(const UnaryOperator *E) { | |||
13778 | if (E->getSubExpr()->getType()->isComplexIntegerType()) { | |||
13779 | ComplexValue LV; | |||
13780 | if (!EvaluateComplex(E->getSubExpr(), LV, Info)) | |||
13781 | return false; | |||
13782 | if (!LV.isComplexInt()) | |||
13783 | return Error(E); | |||
13784 | return Success(LV.getComplexIntImag(), E); | |||
13785 | } | |||
13786 | ||||
13787 | VisitIgnoredValue(E->getSubExpr()); | |||
13788 | return Success(0, E); | |||
13789 | } | |||
13790 | ||||
13791 | bool IntExprEvaluator::VisitSizeOfPackExpr(const SizeOfPackExpr *E) { | |||
13792 | return Success(E->getPackLength(), E); | |||
13793 | } | |||
13794 | ||||
13795 | bool IntExprEvaluator::VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) { | |||
13796 | return Success(E->getValue(), E); | |||
13797 | } | |||
13798 | ||||
13799 | bool IntExprEvaluator::VisitConceptSpecializationExpr( | |||
13800 | const ConceptSpecializationExpr *E) { | |||
13801 | return Success(E->isSatisfied(), E); | |||
13802 | } | |||
13803 | ||||
13804 | bool IntExprEvaluator::VisitRequiresExpr(const RequiresExpr *E) { | |||
13805 | return Success(E->isSatisfied(), E); | |||
13806 | } | |||
13807 | ||||
13808 | bool FixedPointExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { | |||
13809 | switch (E->getOpcode()) { | |||
13810 | default: | |||
13811 | // Invalid unary operators | |||
13812 | return Error(E); | |||
13813 | case UO_Plus: | |||
13814 | // The result is just the value. | |||
13815 | return Visit(E->getSubExpr()); | |||
13816 | case UO_Minus: { | |||
13817 | if (!Visit(E->getSubExpr())) return false; | |||
13818 | if (!Result.isFixedPoint()) | |||
13819 | return Error(E); | |||
13820 | bool Overflowed; | |||
13821 | APFixedPoint Negated = Result.getFixedPoint().negate(&Overflowed); | |||
13822 | if (Overflowed && !HandleOverflow(Info, E, Negated, E->getType())) | |||
13823 | return false; | |||
13824 | return Success(Negated, E); | |||
13825 | } | |||
13826 | case UO_LNot: { | |||
13827 | bool bres; | |||
13828 | if (!EvaluateAsBooleanCondition(E->getSubExpr(), bres, Info)) | |||
13829 | return false; | |||
13830 | return Success(!bres, E); | |||
13831 | } | |||
13832 | } | |||
13833 | } | |||
13834 | ||||
13835 | bool FixedPointExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
13836 | const Expr *SubExpr = E->getSubExpr(); | |||
13837 | QualType DestType = E->getType(); | |||
13838 | assert(DestType->isFixedPointType() &&(static_cast <bool> (DestType->isFixedPointType() && "Expected destination type to be a fixed point type") ? void (0) : __assert_fail ("DestType->isFixedPointType() && \"Expected destination type to be a fixed point type\"" , "clang/lib/AST/ExprConstant.cpp", 13839, __extension__ __PRETTY_FUNCTION__ )) | |||
13839 | "Expected destination type to be a fixed point type")(static_cast <bool> (DestType->isFixedPointType() && "Expected destination type to be a fixed point type") ? void (0) : __assert_fail ("DestType->isFixedPointType() && \"Expected destination type to be a fixed point type\"" , "clang/lib/AST/ExprConstant.cpp", 13839, __extension__ __PRETTY_FUNCTION__ )); | |||
13840 | auto DestFXSema = Info.Ctx.getFixedPointSemantics(DestType); | |||
13841 | ||||
13842 | switch (E->getCastKind()) { | |||
13843 | case CK_FixedPointCast: { | |||
13844 | APFixedPoint Src(Info.Ctx.getFixedPointSemantics(SubExpr->getType())); | |||
13845 | if (!EvaluateFixedPoint(SubExpr, Src, Info)) | |||
13846 | return false; | |||
13847 | bool Overflowed; | |||
13848 | APFixedPoint Result = Src.convert(DestFXSema, &Overflowed); | |||
13849 | if (Overflowed) { | |||
13850 | if (Info.checkingForUndefinedBehavior()) | |||
13851 | Info.Ctx.getDiagnostics().Report(E->getExprLoc(), | |||
13852 | diag::warn_fixedpoint_constant_overflow) | |||
13853 | << Result.toString() << E->getType(); | |||
13854 | if (!HandleOverflow(Info, E, Result, E->getType())) | |||
13855 | return false; | |||
13856 | } | |||
13857 | return Success(Result, E); | |||
13858 | } | |||
13859 | case CK_IntegralToFixedPoint: { | |||
13860 | APSInt Src; | |||
13861 | if (!EvaluateInteger(SubExpr, Src, Info)) | |||
13862 | return false; | |||
13863 | ||||
13864 | bool Overflowed; | |||
13865 | APFixedPoint IntResult = APFixedPoint::getFromIntValue( | |||
13866 | Src, Info.Ctx.getFixedPointSemantics(DestType), &Overflowed); | |||
13867 | ||||
13868 | if (Overflowed) { | |||
13869 | if (Info.checkingForUndefinedBehavior()) | |||
13870 | Info.Ctx.getDiagnostics().Report(E->getExprLoc(), | |||
13871 | diag::warn_fixedpoint_constant_overflow) | |||
13872 | << IntResult.toString() << E->getType(); | |||
13873 | if (!HandleOverflow(Info, E, IntResult, E->getType())) | |||
13874 | return false; | |||
13875 | } | |||
13876 | ||||
13877 | return Success(IntResult, E); | |||
13878 | } | |||
13879 | case CK_FloatingToFixedPoint: { | |||
13880 | APFloat Src(0.0); | |||
13881 | if (!EvaluateFloat(SubExpr, Src, Info)) | |||
13882 | return false; | |||
13883 | ||||
13884 | bool Overflowed; | |||
13885 | APFixedPoint Result = APFixedPoint::getFromFloatValue( | |||
13886 | Src, Info.Ctx.getFixedPointSemantics(DestType), &Overflowed); | |||
13887 | ||||
13888 | if (Overflowed) { | |||
13889 | if (Info.checkingForUndefinedBehavior()) | |||
13890 | Info.Ctx.getDiagnostics().Report(E->getExprLoc(), | |||
13891 | diag::warn_fixedpoint_constant_overflow) | |||
13892 | << Result.toString() << E->getType(); | |||
13893 | if (!HandleOverflow(Info, E, Result, E->getType())) | |||
13894 | return false; | |||
13895 | } | |||
13896 | ||||
13897 | return Success(Result, E); | |||
13898 | } | |||
13899 | case CK_NoOp: | |||
13900 | case CK_LValueToRValue: | |||
13901 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
13902 | default: | |||
13903 | return Error(E); | |||
13904 | } | |||
13905 | } | |||
13906 | ||||
13907 | bool FixedPointExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
13908 | if (E->isPtrMemOp() || E->isAssignmentOp() || E->getOpcode() == BO_Comma) | |||
13909 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
13910 | ||||
13911 | const Expr *LHS = E->getLHS(); | |||
13912 | const Expr *RHS = E->getRHS(); | |||
13913 | FixedPointSemantics ResultFXSema = | |||
13914 | Info.Ctx.getFixedPointSemantics(E->getType()); | |||
13915 | ||||
13916 | APFixedPoint LHSFX(Info.Ctx.getFixedPointSemantics(LHS->getType())); | |||
13917 | if (!EvaluateFixedPointOrInteger(LHS, LHSFX, Info)) | |||
13918 | return false; | |||
13919 | APFixedPoint RHSFX(Info.Ctx.getFixedPointSemantics(RHS->getType())); | |||
13920 | if (!EvaluateFixedPointOrInteger(RHS, RHSFX, Info)) | |||
13921 | return false; | |||
13922 | ||||
13923 | bool OpOverflow = false, ConversionOverflow = false; | |||
13924 | APFixedPoint Result(LHSFX.getSemantics()); | |||
13925 | switch (E->getOpcode()) { | |||
13926 | case BO_Add: { | |||
13927 | Result = LHSFX.add(RHSFX, &OpOverflow) | |||
13928 | .convert(ResultFXSema, &ConversionOverflow); | |||
13929 | break; | |||
13930 | } | |||
13931 | case BO_Sub: { | |||
13932 | Result = LHSFX.sub(RHSFX, &OpOverflow) | |||
13933 | .convert(ResultFXSema, &ConversionOverflow); | |||
13934 | break; | |||
13935 | } | |||
13936 | case BO_Mul: { | |||
13937 | Result = LHSFX.mul(RHSFX, &OpOverflow) | |||
13938 | .convert(ResultFXSema, &ConversionOverflow); | |||
13939 | break; | |||
13940 | } | |||
13941 | case BO_Div: { | |||
13942 | if (RHSFX.getValue() == 0) { | |||
13943 | Info.FFDiag(E, diag::note_expr_divide_by_zero); | |||
13944 | return false; | |||
13945 | } | |||
13946 | Result = LHSFX.div(RHSFX, &OpOverflow) | |||
13947 | .convert(ResultFXSema, &ConversionOverflow); | |||
13948 | break; | |||
13949 | } | |||
13950 | case BO_Shl: | |||
13951 | case BO_Shr: { | |||
13952 | FixedPointSemantics LHSSema = LHSFX.getSemantics(); | |||
13953 | llvm::APSInt RHSVal = RHSFX.getValue(); | |||
13954 | ||||
13955 | unsigned ShiftBW = | |||
13956 | LHSSema.getWidth() - (unsigned)LHSSema.hasUnsignedPadding(); | |||
13957 | unsigned Amt = RHSVal.getLimitedValue(ShiftBW - 1); | |||
13958 | // Embedded-C 4.1.6.2.2: | |||
13959 | // The right operand must be nonnegative and less than the total number | |||
13960 | // of (nonpadding) bits of the fixed-point operand ... | |||
13961 | if (RHSVal.isNegative()) | |||
13962 | Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHSVal; | |||
13963 | else if (Amt != RHSVal) | |||
13964 | Info.CCEDiag(E, diag::note_constexpr_large_shift) | |||
13965 | << RHSVal << E->getType() << ShiftBW; | |||
13966 | ||||
13967 | if (E->getOpcode() == BO_Shl) | |||
13968 | Result = LHSFX.shl(Amt, &OpOverflow); | |||
13969 | else | |||
13970 | Result = LHSFX.shr(Amt, &OpOverflow); | |||
13971 | break; | |||
13972 | } | |||
13973 | default: | |||
13974 | return false; | |||
13975 | } | |||
13976 | if (OpOverflow || ConversionOverflow) { | |||
13977 | if (Info.checkingForUndefinedBehavior()) | |||
13978 | Info.Ctx.getDiagnostics().Report(E->getExprLoc(), | |||
13979 | diag::warn_fixedpoint_constant_overflow) | |||
13980 | << Result.toString() << E->getType(); | |||
13981 | if (!HandleOverflow(Info, E, Result, E->getType())) | |||
13982 | return false; | |||
13983 | } | |||
13984 | return Success(Result, E); | |||
13985 | } | |||
13986 | ||||
13987 | //===----------------------------------------------------------------------===// | |||
13988 | // Float Evaluation | |||
13989 | //===----------------------------------------------------------------------===// | |||
13990 | ||||
13991 | namespace { | |||
13992 | class FloatExprEvaluator | |||
13993 | : public ExprEvaluatorBase<FloatExprEvaluator> { | |||
13994 | APFloat &Result; | |||
13995 | public: | |||
13996 | FloatExprEvaluator(EvalInfo &info, APFloat &result) | |||
13997 | : ExprEvaluatorBaseTy(info), Result(result) {} | |||
13998 | ||||
13999 | bool Success(const APValue &V, const Expr *e) { | |||
14000 | Result = V.getFloat(); | |||
14001 | return true; | |||
14002 | } | |||
14003 | ||||
14004 | bool ZeroInitialization(const Expr *E) { | |||
14005 | Result = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(E->getType())); | |||
14006 | return true; | |||
14007 | } | |||
14008 | ||||
14009 | bool VisitCallExpr(const CallExpr *E); | |||
14010 | ||||
14011 | bool VisitUnaryOperator(const UnaryOperator *E); | |||
14012 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
14013 | bool VisitFloatingLiteral(const FloatingLiteral *E); | |||
14014 | bool VisitCastExpr(const CastExpr *E); | |||
14015 | ||||
14016 | bool VisitUnaryReal(const UnaryOperator *E); | |||
14017 | bool VisitUnaryImag(const UnaryOperator *E); | |||
14018 | ||||
14019 | // FIXME: Missing: array subscript of vector, member of vector | |||
14020 | }; | |||
14021 | } // end anonymous namespace | |||
14022 | ||||
14023 | static bool EvaluateFloat(const Expr* E, APFloat& Result, EvalInfo &Info) { | |||
14024 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 14024, __extension__ __PRETTY_FUNCTION__)); | |||
14025 | assert(E->isPRValue() && E->getType()->isRealFloatingType())(static_cast <bool> (E->isPRValue() && E-> getType()->isRealFloatingType()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isRealFloatingType()" , "clang/lib/AST/ExprConstant.cpp", 14025, __extension__ __PRETTY_FUNCTION__ )); | |||
14026 | return FloatExprEvaluator(Info, Result).Visit(E); | |||
14027 | } | |||
14028 | ||||
14029 | static bool TryEvaluateBuiltinNaN(const ASTContext &Context, | |||
14030 | QualType ResultTy, | |||
14031 | const Expr *Arg, | |||
14032 | bool SNaN, | |||
14033 | llvm::APFloat &Result) { | |||
14034 | const StringLiteral *S = dyn_cast<StringLiteral>(Arg->IgnoreParenCasts()); | |||
14035 | if (!S) return false; | |||
14036 | ||||
14037 | const llvm::fltSemantics &Sem = Context.getFloatTypeSemantics(ResultTy); | |||
14038 | ||||
14039 | llvm::APInt fill; | |||
14040 | ||||
14041 | // Treat empty strings as if they were zero. | |||
14042 | if (S->getString().empty()) | |||
14043 | fill = llvm::APInt(32, 0); | |||
14044 | else if (S->getString().getAsInteger(0, fill)) | |||
14045 | return false; | |||
14046 | ||||
14047 | if (Context.getTargetInfo().isNan2008()) { | |||
14048 | if (SNaN) | |||
14049 | Result = llvm::APFloat::getSNaN(Sem, false, &fill); | |||
14050 | else | |||
14051 | Result = llvm::APFloat::getQNaN(Sem, false, &fill); | |||
14052 | } else { | |||
14053 | // Prior to IEEE 754-2008, architectures were allowed to choose whether | |||
14054 | // the first bit of their significand was set for qNaN or sNaN. MIPS chose | |||
14055 | // a different encoding to what became a standard in 2008, and for pre- | |||
14056 | // 2008 revisions, MIPS interpreted sNaN-2008 as qNan and qNaN-2008 as | |||
14057 | // sNaN. This is now known as "legacy NaN" encoding. | |||
14058 | if (SNaN) | |||
14059 | Result = llvm::APFloat::getQNaN(Sem, false, &fill); | |||
14060 | else | |||
14061 | Result = llvm::APFloat::getSNaN(Sem, false, &fill); | |||
14062 | } | |||
14063 | ||||
14064 | return true; | |||
14065 | } | |||
14066 | ||||
14067 | bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) { | |||
14068 | if (!IsConstantEvaluatedBuiltinCall(E)) | |||
14069 | return ExprEvaluatorBaseTy::VisitCallExpr(E); | |||
14070 | ||||
14071 | switch (E->getBuiltinCallee()) { | |||
14072 | default: | |||
14073 | return false; | |||
14074 | ||||
14075 | case Builtin::BI__builtin_huge_val: | |||
14076 | case Builtin::BI__builtin_huge_valf: | |||
14077 | case Builtin::BI__builtin_huge_vall: | |||
14078 | case Builtin::BI__builtin_huge_valf16: | |||
14079 | case Builtin::BI__builtin_huge_valf128: | |||
14080 | case Builtin::BI__builtin_inf: | |||
14081 | case Builtin::BI__builtin_inff: | |||
14082 | case Builtin::BI__builtin_infl: | |||
14083 | case Builtin::BI__builtin_inff16: | |||
14084 | case Builtin::BI__builtin_inff128: { | |||
14085 | const llvm::fltSemantics &Sem = | |||
14086 | Info.Ctx.getFloatTypeSemantics(E->getType()); | |||
14087 | Result = llvm::APFloat::getInf(Sem); | |||
14088 | return true; | |||
14089 | } | |||
14090 | ||||
14091 | case Builtin::BI__builtin_nans: | |||
14092 | case Builtin::BI__builtin_nansf: | |||
14093 | case Builtin::BI__builtin_nansl: | |||
14094 | case Builtin::BI__builtin_nansf16: | |||
14095 | case Builtin::BI__builtin_nansf128: | |||
14096 | if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0), | |||
14097 | true, Result)) | |||
14098 | return Error(E); | |||
14099 | return true; | |||
14100 | ||||
14101 | case Builtin::BI__builtin_nan: | |||
14102 | case Builtin::BI__builtin_nanf: | |||
14103 | case Builtin::BI__builtin_nanl: | |||
14104 | case Builtin::BI__builtin_nanf16: | |||
14105 | case Builtin::BI__builtin_nanf128: | |||
14106 | // If this is __builtin_nan() turn this into a nan, otherwise we | |||
14107 | // can't constant fold it. | |||
14108 | if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0), | |||
14109 | false, Result)) | |||
14110 | return Error(E); | |||
14111 | return true; | |||
14112 | ||||
14113 | case Builtin::BI__builtin_fabs: | |||
14114 | case Builtin::BI__builtin_fabsf: | |||
14115 | case Builtin::BI__builtin_fabsl: | |||
14116 | case Builtin::BI__builtin_fabsf128: | |||
14117 | // The C standard says "fabs raises no floating-point exceptions, | |||
14118 | // even if x is a signaling NaN. The returned value is independent of | |||
14119 | // the current rounding direction mode." Therefore constant folding can | |||
14120 | // proceed without regard to the floating point settings. | |||
14121 | // Reference, WG14 N2478 F.10.4.3 | |||
14122 | if (!EvaluateFloat(E->getArg(0), Result, Info)) | |||
14123 | return false; | |||
14124 | ||||
14125 | if (Result.isNegative()) | |||
14126 | Result.changeSign(); | |||
14127 | return true; | |||
14128 | ||||
14129 | case Builtin::BI__arithmetic_fence: | |||
14130 | return EvaluateFloat(E->getArg(0), Result, Info); | |||
14131 | ||||
14132 | // FIXME: Builtin::BI__builtin_powi | |||
14133 | // FIXME: Builtin::BI__builtin_powif | |||
14134 | // FIXME: Builtin::BI__builtin_powil | |||
14135 | ||||
14136 | case Builtin::BI__builtin_copysign: | |||
14137 | case Builtin::BI__builtin_copysignf: | |||
14138 | case Builtin::BI__builtin_copysignl: | |||
14139 | case Builtin::BI__builtin_copysignf128: { | |||
14140 | APFloat RHS(0.); | |||
14141 | if (!EvaluateFloat(E->getArg(0), Result, Info) || | |||
14142 | !EvaluateFloat(E->getArg(1), RHS, Info)) | |||
14143 | return false; | |||
14144 | Result.copySign(RHS); | |||
14145 | return true; | |||
14146 | } | |||
14147 | ||||
14148 | case Builtin::BI__builtin_fmax: | |||
14149 | case Builtin::BI__builtin_fmaxf: | |||
14150 | case Builtin::BI__builtin_fmaxl: | |||
14151 | case Builtin::BI__builtin_fmaxf16: | |||
14152 | case Builtin::BI__builtin_fmaxf128: { | |||
14153 | // TODO: Handle sNaN. | |||
14154 | APFloat RHS(0.); | |||
14155 | if (!EvaluateFloat(E->getArg(0), Result, Info) || | |||
14156 | !EvaluateFloat(E->getArg(1), RHS, Info)) | |||
14157 | return false; | |||
14158 | // When comparing zeroes, return +0.0 if one of the zeroes is positive. | |||
14159 | if (Result.isZero() && RHS.isZero() && Result.isNegative()) | |||
14160 | Result = RHS; | |||
14161 | else if (Result.isNaN() || RHS > Result) | |||
14162 | Result = RHS; | |||
14163 | return true; | |||
14164 | } | |||
14165 | ||||
14166 | case Builtin::BI__builtin_fmin: | |||
14167 | case Builtin::BI__builtin_fminf: | |||
14168 | case Builtin::BI__builtin_fminl: | |||
14169 | case Builtin::BI__builtin_fminf16: | |||
14170 | case Builtin::BI__builtin_fminf128: { | |||
14171 | // TODO: Handle sNaN. | |||
14172 | APFloat RHS(0.); | |||
14173 | if (!EvaluateFloat(E->getArg(0), Result, Info) || | |||
14174 | !EvaluateFloat(E->getArg(1), RHS, Info)) | |||
14175 | return false; | |||
14176 | // When comparing zeroes, return -0.0 if one of the zeroes is negative. | |||
14177 | if (Result.isZero() && RHS.isZero() && RHS.isNegative()) | |||
14178 | Result = RHS; | |||
14179 | else if (Result.isNaN() || RHS < Result) | |||
14180 | Result = RHS; | |||
14181 | return true; | |||
14182 | } | |||
14183 | } | |||
14184 | } | |||
14185 | ||||
14186 | bool FloatExprEvaluator::VisitUnaryReal(const UnaryOperator *E) { | |||
14187 | if (E->getSubExpr()->getType()->isAnyComplexType()) { | |||
14188 | ComplexValue CV; | |||
14189 | if (!EvaluateComplex(E->getSubExpr(), CV, Info)) | |||
14190 | return false; | |||
14191 | Result = CV.FloatReal; | |||
14192 | return true; | |||
14193 | } | |||
14194 | ||||
14195 | return Visit(E->getSubExpr()); | |||
14196 | } | |||
14197 | ||||
14198 | bool FloatExprEvaluator::VisitUnaryImag(const UnaryOperator *E) { | |||
14199 | if (E->getSubExpr()->getType()->isAnyComplexType()) { | |||
14200 | ComplexValue CV; | |||
14201 | if (!EvaluateComplex(E->getSubExpr(), CV, Info)) | |||
14202 | return false; | |||
14203 | Result = CV.FloatImag; | |||
14204 | return true; | |||
14205 | } | |||
14206 | ||||
14207 | VisitIgnoredValue(E->getSubExpr()); | |||
14208 | const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(E->getType()); | |||
14209 | Result = llvm::APFloat::getZero(Sem); | |||
14210 | return true; | |||
14211 | } | |||
14212 | ||||
14213 | bool FloatExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { | |||
14214 | switch (E->getOpcode()) { | |||
14215 | default: return Error(E); | |||
14216 | case UO_Plus: | |||
14217 | return EvaluateFloat(E->getSubExpr(), Result, Info); | |||
14218 | case UO_Minus: | |||
14219 | // In C standard, WG14 N2478 F.3 p4 | |||
14220 | // "the unary - raises no floating point exceptions, | |||
14221 | // even if the operand is signalling." | |||
14222 | if (!EvaluateFloat(E->getSubExpr(), Result, Info)) | |||
14223 | return false; | |||
14224 | Result.changeSign(); | |||
14225 | return true; | |||
14226 | } | |||
14227 | } | |||
14228 | ||||
14229 | bool FloatExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
14230 | if (E->isPtrMemOp() || E->isAssignmentOp() || E->getOpcode() == BO_Comma) | |||
14231 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
14232 | ||||
14233 | APFloat RHS(0.0); | |||
14234 | bool LHSOK = EvaluateFloat(E->getLHS(), Result, Info); | |||
14235 | if (!LHSOK && !Info.noteFailure()) | |||
14236 | return false; | |||
14237 | return EvaluateFloat(E->getRHS(), RHS, Info) && LHSOK && | |||
14238 | handleFloatFloatBinOp(Info, E, Result, E->getOpcode(), RHS); | |||
14239 | } | |||
14240 | ||||
14241 | bool FloatExprEvaluator::VisitFloatingLiteral(const FloatingLiteral *E) { | |||
14242 | Result = E->getValue(); | |||
14243 | return true; | |||
14244 | } | |||
14245 | ||||
14246 | bool FloatExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
14247 | const Expr* SubExpr = E->getSubExpr(); | |||
14248 | ||||
14249 | switch (E->getCastKind()) { | |||
14250 | default: | |||
14251 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
14252 | ||||
14253 | case CK_IntegralToFloating: { | |||
14254 | APSInt IntResult; | |||
14255 | const FPOptions FPO = E->getFPFeaturesInEffect( | |||
14256 | Info.Ctx.getLangOpts()); | |||
14257 | return EvaluateInteger(SubExpr, IntResult, Info) && | |||
14258 | HandleIntToFloatCast(Info, E, FPO, SubExpr->getType(), | |||
14259 | IntResult, E->getType(), Result); | |||
14260 | } | |||
14261 | ||||
14262 | case CK_FixedPointToFloating: { | |||
14263 | APFixedPoint FixResult(Info.Ctx.getFixedPointSemantics(SubExpr->getType())); | |||
14264 | if (!EvaluateFixedPoint(SubExpr, FixResult, Info)) | |||
14265 | return false; | |||
14266 | Result = | |||
14267 | FixResult.convertToFloat(Info.Ctx.getFloatTypeSemantics(E->getType())); | |||
14268 | return true; | |||
14269 | } | |||
14270 | ||||
14271 | case CK_FloatingCast: { | |||
14272 | if (!Visit(SubExpr)) | |||
14273 | return false; | |||
14274 | return HandleFloatToFloatCast(Info, E, SubExpr->getType(), E->getType(), | |||
14275 | Result); | |||
14276 | } | |||
14277 | ||||
14278 | case CK_FloatingComplexToReal: { | |||
14279 | ComplexValue V; | |||
14280 | if (!EvaluateComplex(SubExpr, V, Info)) | |||
14281 | return false; | |||
14282 | Result = V.getComplexFloatReal(); | |||
14283 | return true; | |||
14284 | } | |||
14285 | } | |||
14286 | } | |||
14287 | ||||
14288 | //===----------------------------------------------------------------------===// | |||
14289 | // Complex Evaluation (for float and integer) | |||
14290 | //===----------------------------------------------------------------------===// | |||
14291 | ||||
14292 | namespace { | |||
14293 | class ComplexExprEvaluator | |||
14294 | : public ExprEvaluatorBase<ComplexExprEvaluator> { | |||
14295 | ComplexValue &Result; | |||
14296 | ||||
14297 | public: | |||
14298 | ComplexExprEvaluator(EvalInfo &info, ComplexValue &Result) | |||
14299 | : ExprEvaluatorBaseTy(info), Result(Result) {} | |||
14300 | ||||
14301 | bool Success(const APValue &V, const Expr *e) { | |||
14302 | Result.setFrom(V); | |||
14303 | return true; | |||
14304 | } | |||
14305 | ||||
14306 | bool ZeroInitialization(const Expr *E); | |||
14307 | ||||
14308 | //===--------------------------------------------------------------------===// | |||
14309 | // Visitor Methods | |||
14310 | //===--------------------------------------------------------------------===// | |||
14311 | ||||
14312 | bool VisitImaginaryLiteral(const ImaginaryLiteral *E); | |||
14313 | bool VisitCastExpr(const CastExpr *E); | |||
14314 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
14315 | bool VisitUnaryOperator(const UnaryOperator *E); | |||
14316 | bool VisitInitListExpr(const InitListExpr *E); | |||
14317 | bool VisitCallExpr(const CallExpr *E); | |||
14318 | }; | |||
14319 | } // end anonymous namespace | |||
14320 | ||||
14321 | static bool EvaluateComplex(const Expr *E, ComplexValue &Result, | |||
14322 | EvalInfo &Info) { | |||
14323 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 14323, __extension__ __PRETTY_FUNCTION__)); | |||
14324 | assert(E->isPRValue() && E->getType()->isAnyComplexType())(static_cast <bool> (E->isPRValue() && E-> getType()->isAnyComplexType()) ? void (0) : __assert_fail ( "E->isPRValue() && E->getType()->isAnyComplexType()" , "clang/lib/AST/ExprConstant.cpp", 14324, __extension__ __PRETTY_FUNCTION__ )); | |||
14325 | return ComplexExprEvaluator(Info, Result).Visit(E); | |||
14326 | } | |||
14327 | ||||
14328 | bool ComplexExprEvaluator::ZeroInitialization(const Expr *E) { | |||
14329 | QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType(); | |||
14330 | if (ElemTy->isRealFloatingType()) { | |||
14331 | Result.makeComplexFloat(); | |||
14332 | APFloat Zero = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(ElemTy)); | |||
14333 | Result.FloatReal = Zero; | |||
14334 | Result.FloatImag = Zero; | |||
14335 | } else { | |||
14336 | Result.makeComplexInt(); | |||
14337 | APSInt Zero = Info.Ctx.MakeIntValue(0, ElemTy); | |||
14338 | Result.IntReal = Zero; | |||
14339 | Result.IntImag = Zero; | |||
14340 | } | |||
14341 | return true; | |||
14342 | } | |||
14343 | ||||
14344 | bool ComplexExprEvaluator::VisitImaginaryLiteral(const ImaginaryLiteral *E) { | |||
14345 | const Expr* SubExpr = E->getSubExpr(); | |||
14346 | ||||
14347 | if (SubExpr->getType()->isRealFloatingType()) { | |||
14348 | Result.makeComplexFloat(); | |||
14349 | APFloat &Imag = Result.FloatImag; | |||
14350 | if (!EvaluateFloat(SubExpr, Imag, Info)) | |||
14351 | return false; | |||
14352 | ||||
14353 | Result.FloatReal = APFloat(Imag.getSemantics()); | |||
14354 | return true; | |||
14355 | } else { | |||
14356 | assert(SubExpr->getType()->isIntegerType() &&(static_cast <bool> (SubExpr->getType()->isIntegerType () && "Unexpected imaginary literal.") ? void (0) : __assert_fail ("SubExpr->getType()->isIntegerType() && \"Unexpected imaginary literal.\"" , "clang/lib/AST/ExprConstant.cpp", 14357, __extension__ __PRETTY_FUNCTION__ )) | |||
14357 | "Unexpected imaginary literal.")(static_cast <bool> (SubExpr->getType()->isIntegerType () && "Unexpected imaginary literal.") ? void (0) : __assert_fail ("SubExpr->getType()->isIntegerType() && \"Unexpected imaginary literal.\"" , "clang/lib/AST/ExprConstant.cpp", 14357, __extension__ __PRETTY_FUNCTION__ )); | |||
14358 | ||||
14359 | Result.makeComplexInt(); | |||
14360 | APSInt &Imag = Result.IntImag; | |||
14361 | if (!EvaluateInteger(SubExpr, Imag, Info)) | |||
14362 | return false; | |||
14363 | ||||
14364 | Result.IntReal = APSInt(Imag.getBitWidth(), !Imag.isSigned()); | |||
14365 | return true; | |||
14366 | } | |||
14367 | } | |||
14368 | ||||
14369 | bool ComplexExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
14370 | ||||
14371 | switch (E->getCastKind()) { | |||
14372 | case CK_BitCast: | |||
14373 | case CK_BaseToDerived: | |||
14374 | case CK_DerivedToBase: | |||
14375 | case CK_UncheckedDerivedToBase: | |||
14376 | case CK_Dynamic: | |||
14377 | case CK_ToUnion: | |||
14378 | case CK_ArrayToPointerDecay: | |||
14379 | case CK_FunctionToPointerDecay: | |||
14380 | case CK_NullToPointer: | |||
14381 | case CK_NullToMemberPointer: | |||
14382 | case CK_BaseToDerivedMemberPointer: | |||
14383 | case CK_DerivedToBaseMemberPointer: | |||
14384 | case CK_MemberPointerToBoolean: | |||
14385 | case CK_ReinterpretMemberPointer: | |||
14386 | case CK_ConstructorConversion: | |||
14387 | case CK_IntegralToPointer: | |||
14388 | case CK_PointerToIntegral: | |||
14389 | case CK_PointerToBoolean: | |||
14390 | case CK_ToVoid: | |||
14391 | case CK_VectorSplat: | |||
14392 | case CK_IntegralCast: | |||
14393 | case CK_BooleanToSignedIntegral: | |||
14394 | case CK_IntegralToBoolean: | |||
14395 | case CK_IntegralToFloating: | |||
14396 | case CK_FloatingToIntegral: | |||
14397 | case CK_FloatingToBoolean: | |||
14398 | case CK_FloatingCast: | |||
14399 | case CK_CPointerToObjCPointerCast: | |||
14400 | case CK_BlockPointerToObjCPointerCast: | |||
14401 | case CK_AnyPointerToBlockPointerCast: | |||
14402 | case CK_ObjCObjectLValueCast: | |||
14403 | case CK_FloatingComplexToReal: | |||
14404 | case CK_FloatingComplexToBoolean: | |||
14405 | case CK_IntegralComplexToReal: | |||
14406 | case CK_IntegralComplexToBoolean: | |||
14407 | case CK_ARCProduceObject: | |||
14408 | case CK_ARCConsumeObject: | |||
14409 | case CK_ARCReclaimReturnedObject: | |||
14410 | case CK_ARCExtendBlockObject: | |||
14411 | case CK_CopyAndAutoreleaseBlockObject: | |||
14412 | case CK_BuiltinFnToFnPtr: | |||
14413 | case CK_ZeroToOCLOpaqueType: | |||
14414 | case CK_NonAtomicToAtomic: | |||
14415 | case CK_AddressSpaceConversion: | |||
14416 | case CK_IntToOCLSampler: | |||
14417 | case CK_FloatingToFixedPoint: | |||
14418 | case CK_FixedPointToFloating: | |||
14419 | case CK_FixedPointCast: | |||
14420 | case CK_FixedPointToBoolean: | |||
14421 | case CK_FixedPointToIntegral: | |||
14422 | case CK_IntegralToFixedPoint: | |||
14423 | case CK_MatrixCast: | |||
14424 | llvm_unreachable("invalid cast kind for complex value")::llvm::llvm_unreachable_internal("invalid cast kind for complex value" , "clang/lib/AST/ExprConstant.cpp", 14424); | |||
14425 | ||||
14426 | case CK_LValueToRValue: | |||
14427 | case CK_AtomicToNonAtomic: | |||
14428 | case CK_NoOp: | |||
14429 | case CK_LValueToRValueBitCast: | |||
14430 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
14431 | ||||
14432 | case CK_Dependent: | |||
14433 | case CK_LValueBitCast: | |||
14434 | case CK_UserDefinedConversion: | |||
14435 | return Error(E); | |||
14436 | ||||
14437 | case CK_FloatingRealToComplex: { | |||
14438 | APFloat &Real = Result.FloatReal; | |||
14439 | if (!EvaluateFloat(E->getSubExpr(), Real, Info)) | |||
14440 | return false; | |||
14441 | ||||
14442 | Result.makeComplexFloat(); | |||
14443 | Result.FloatImag = APFloat(Real.getSemantics()); | |||
14444 | return true; | |||
14445 | } | |||
14446 | ||||
14447 | case CK_FloatingComplexCast: { | |||
14448 | if (!Visit(E->getSubExpr())) | |||
14449 | return false; | |||
14450 | ||||
14451 | QualType To = E->getType()->castAs<ComplexType>()->getElementType(); | |||
14452 | QualType From | |||
14453 | = E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType(); | |||
14454 | ||||
14455 | return HandleFloatToFloatCast(Info, E, From, To, Result.FloatReal) && | |||
14456 | HandleFloatToFloatCast(Info, E, From, To, Result.FloatImag); | |||
14457 | } | |||
14458 | ||||
14459 | case CK_FloatingComplexToIntegralComplex: { | |||
14460 | if (!Visit(E->getSubExpr())) | |||
14461 | return false; | |||
14462 | ||||
14463 | QualType To = E->getType()->castAs<ComplexType>()->getElementType(); | |||
14464 | QualType From | |||
14465 | = E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType(); | |||
14466 | Result.makeComplexInt(); | |||
14467 | return HandleFloatToIntCast(Info, E, From, Result.FloatReal, | |||
14468 | To, Result.IntReal) && | |||
14469 | HandleFloatToIntCast(Info, E, From, Result.FloatImag, | |||
14470 | To, Result.IntImag); | |||
14471 | } | |||
14472 | ||||
14473 | case CK_IntegralRealToComplex: { | |||
14474 | APSInt &Real = Result.IntReal; | |||
14475 | if (!EvaluateInteger(E->getSubExpr(), Real, Info)) | |||
14476 | return false; | |||
14477 | ||||
14478 | Result.makeComplexInt(); | |||
14479 | Result.IntImag = APSInt(Real.getBitWidth(), !Real.isSigned()); | |||
14480 | return true; | |||
14481 | } | |||
14482 | ||||
14483 | case CK_IntegralComplexCast: { | |||
14484 | if (!Visit(E->getSubExpr())) | |||
14485 | return false; | |||
14486 | ||||
14487 | QualType To = E->getType()->castAs<ComplexType>()->getElementType(); | |||
14488 | QualType From | |||
14489 | = E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType(); | |||
14490 | ||||
14491 | Result.IntReal = HandleIntToIntCast(Info, E, To, From, Result.IntReal); | |||
14492 | Result.IntImag = HandleIntToIntCast(Info, E, To, From, Result.IntImag); | |||
14493 | return true; | |||
14494 | } | |||
14495 | ||||
14496 | case CK_IntegralComplexToFloatingComplex: { | |||
14497 | if (!Visit(E->getSubExpr())) | |||
14498 | return false; | |||
14499 | ||||
14500 | const FPOptions FPO = E->getFPFeaturesInEffect( | |||
14501 | Info.Ctx.getLangOpts()); | |||
14502 | QualType To = E->getType()->castAs<ComplexType>()->getElementType(); | |||
14503 | QualType From | |||
14504 | = E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType(); | |||
14505 | Result.makeComplexFloat(); | |||
14506 | return HandleIntToFloatCast(Info, E, FPO, From, Result.IntReal, | |||
14507 | To, Result.FloatReal) && | |||
14508 | HandleIntToFloatCast(Info, E, FPO, From, Result.IntImag, | |||
14509 | To, Result.FloatImag); | |||
14510 | } | |||
14511 | } | |||
14512 | ||||
14513 | llvm_unreachable("unknown cast resulting in complex value")::llvm::llvm_unreachable_internal("unknown cast resulting in complex value" , "clang/lib/AST/ExprConstant.cpp", 14513); | |||
14514 | } | |||
14515 | ||||
14516 | bool ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
14517 | if (E->isPtrMemOp() || E->isAssignmentOp() || E->getOpcode() == BO_Comma) | |||
14518 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
14519 | ||||
14520 | // Track whether the LHS or RHS is real at the type system level. When this is | |||
14521 | // the case we can simplify our evaluation strategy. | |||
14522 | bool LHSReal = false, RHSReal = false; | |||
14523 | ||||
14524 | bool LHSOK; | |||
14525 | if (E->getLHS()->getType()->isRealFloatingType()) { | |||
14526 | LHSReal = true; | |||
14527 | APFloat &Real = Result.FloatReal; | |||
14528 | LHSOK = EvaluateFloat(E->getLHS(), Real, Info); | |||
14529 | if (LHSOK) { | |||
14530 | Result.makeComplexFloat(); | |||
14531 | Result.FloatImag = APFloat(Real.getSemantics()); | |||
14532 | } | |||
14533 | } else { | |||
14534 | LHSOK = Visit(E->getLHS()); | |||
14535 | } | |||
14536 | if (!LHSOK && !Info.noteFailure()) | |||
14537 | return false; | |||
14538 | ||||
14539 | ComplexValue RHS; | |||
14540 | if (E->getRHS()->getType()->isRealFloatingType()) { | |||
14541 | RHSReal = true; | |||
14542 | APFloat &Real = RHS.FloatReal; | |||
14543 | if (!EvaluateFloat(E->getRHS(), Real, Info) || !LHSOK) | |||
14544 | return false; | |||
14545 | RHS.makeComplexFloat(); | |||
14546 | RHS.FloatImag = APFloat(Real.getSemantics()); | |||
14547 | } else if (!EvaluateComplex(E->getRHS(), RHS, Info) || !LHSOK) | |||
14548 | return false; | |||
14549 | ||||
14550 | assert(!(LHSReal && RHSReal) &&(static_cast <bool> (!(LHSReal && RHSReal) && "Cannot have both operands of a complex operation be real.") ? void (0) : __assert_fail ("!(LHSReal && RHSReal) && \"Cannot have both operands of a complex operation be real.\"" , "clang/lib/AST/ExprConstant.cpp", 14551, __extension__ __PRETTY_FUNCTION__ )) | |||
14551 | "Cannot have both operands of a complex operation be real.")(static_cast <bool> (!(LHSReal && RHSReal) && "Cannot have both operands of a complex operation be real.") ? void (0) : __assert_fail ("!(LHSReal && RHSReal) && \"Cannot have both operands of a complex operation be real.\"" , "clang/lib/AST/ExprConstant.cpp", 14551, __extension__ __PRETTY_FUNCTION__ )); | |||
14552 | switch (E->getOpcode()) { | |||
14553 | default: return Error(E); | |||
14554 | case BO_Add: | |||
14555 | if (Result.isComplexFloat()) { | |||
14556 | Result.getComplexFloatReal().add(RHS.getComplexFloatReal(), | |||
14557 | APFloat::rmNearestTiesToEven); | |||
14558 | if (LHSReal) | |||
14559 | Result.getComplexFloatImag() = RHS.getComplexFloatImag(); | |||
14560 | else if (!RHSReal) | |||
14561 | Result.getComplexFloatImag().add(RHS.getComplexFloatImag(), | |||
14562 | APFloat::rmNearestTiesToEven); | |||
14563 | } else { | |||
14564 | Result.getComplexIntReal() += RHS.getComplexIntReal(); | |||
14565 | Result.getComplexIntImag() += RHS.getComplexIntImag(); | |||
14566 | } | |||
14567 | break; | |||
14568 | case BO_Sub: | |||
14569 | if (Result.isComplexFloat()) { | |||
14570 | Result.getComplexFloatReal().subtract(RHS.getComplexFloatReal(), | |||
14571 | APFloat::rmNearestTiesToEven); | |||
14572 | if (LHSReal) { | |||
14573 | Result.getComplexFloatImag() = RHS.getComplexFloatImag(); | |||
14574 | Result.getComplexFloatImag().changeSign(); | |||
14575 | } else if (!RHSReal) { | |||
14576 | Result.getComplexFloatImag().subtract(RHS.getComplexFloatImag(), | |||
14577 | APFloat::rmNearestTiesToEven); | |||
14578 | } | |||
14579 | } else { | |||
14580 | Result.getComplexIntReal() -= RHS.getComplexIntReal(); | |||
14581 | Result.getComplexIntImag() -= RHS.getComplexIntImag(); | |||
14582 | } | |||
14583 | break; | |||
14584 | case BO_Mul: | |||
14585 | if (Result.isComplexFloat()) { | |||
14586 | // This is an implementation of complex multiplication according to the | |||
14587 | // constraints laid out in C11 Annex G. The implementation uses the | |||
14588 | // following naming scheme: | |||
14589 | // (a + ib) * (c + id) | |||
14590 | ComplexValue LHS = Result; | |||
14591 | APFloat &A = LHS.getComplexFloatReal(); | |||
14592 | APFloat &B = LHS.getComplexFloatImag(); | |||
14593 | APFloat &C = RHS.getComplexFloatReal(); | |||
14594 | APFloat &D = RHS.getComplexFloatImag(); | |||
14595 | APFloat &ResR = Result.getComplexFloatReal(); | |||
14596 | APFloat &ResI = Result.getComplexFloatImag(); | |||
14597 | if (LHSReal) { | |||
14598 | assert(!RHSReal && "Cannot have two real operands for a complex op!")(static_cast <bool> (!RHSReal && "Cannot have two real operands for a complex op!" ) ? void (0) : __assert_fail ("!RHSReal && \"Cannot have two real operands for a complex op!\"" , "clang/lib/AST/ExprConstant.cpp", 14598, __extension__ __PRETTY_FUNCTION__ )); | |||
14599 | ResR = A * C; | |||
14600 | ResI = A * D; | |||
14601 | } else if (RHSReal) { | |||
14602 | ResR = C * A; | |||
14603 | ResI = C * B; | |||
14604 | } else { | |||
14605 | // In the fully general case, we need to handle NaNs and infinities | |||
14606 | // robustly. | |||
14607 | APFloat AC = A * C; | |||
14608 | APFloat BD = B * D; | |||
14609 | APFloat AD = A * D; | |||
14610 | APFloat BC = B * C; | |||
14611 | ResR = AC - BD; | |||
14612 | ResI = AD + BC; | |||
14613 | if (ResR.isNaN() && ResI.isNaN()) { | |||
14614 | bool Recalc = false; | |||
14615 | if (A.isInfinity() || B.isInfinity()) { | |||
14616 | A = APFloat::copySign( | |||
14617 | APFloat(A.getSemantics(), A.isInfinity() ? 1 : 0), A); | |||
14618 | B = APFloat::copySign( | |||
14619 | APFloat(B.getSemantics(), B.isInfinity() ? 1 : 0), B); | |||
14620 | if (C.isNaN()) | |||
14621 | C = APFloat::copySign(APFloat(C.getSemantics()), C); | |||
14622 | if (D.isNaN()) | |||
14623 | D = APFloat::copySign(APFloat(D.getSemantics()), D); | |||
14624 | Recalc = true; | |||
14625 | } | |||
14626 | if (C.isInfinity() || D.isInfinity()) { | |||
14627 | C = APFloat::copySign( | |||
14628 | APFloat(C.getSemantics(), C.isInfinity() ? 1 : 0), C); | |||
14629 | D = APFloat::copySign( | |||
14630 | APFloat(D.getSemantics(), D.isInfinity() ? 1 : 0), D); | |||
14631 | if (A.isNaN()) | |||
14632 | A = APFloat::copySign(APFloat(A.getSemantics()), A); | |||
14633 | if (B.isNaN()) | |||
14634 | B = APFloat::copySign(APFloat(B.getSemantics()), B); | |||
14635 | Recalc = true; | |||
14636 | } | |||
14637 | if (!Recalc && (AC.isInfinity() || BD.isInfinity() || | |||
14638 | AD.isInfinity() || BC.isInfinity())) { | |||
14639 | if (A.isNaN()) | |||
14640 | A = APFloat::copySign(APFloat(A.getSemantics()), A); | |||
14641 | if (B.isNaN()) | |||
14642 | B = APFloat::copySign(APFloat(B.getSemantics()), B); | |||
14643 | if (C.isNaN()) | |||
14644 | C = APFloat::copySign(APFloat(C.getSemantics()), C); | |||
14645 | if (D.isNaN()) | |||
14646 | D = APFloat::copySign(APFloat(D.getSemantics()), D); | |||
14647 | Recalc = true; | |||
14648 | } | |||
14649 | if (Recalc) { | |||
14650 | ResR = APFloat::getInf(A.getSemantics()) * (A * C - B * D); | |||
14651 | ResI = APFloat::getInf(A.getSemantics()) * (A * D + B * C); | |||
14652 | } | |||
14653 | } | |||
14654 | } | |||
14655 | } else { | |||
14656 | ComplexValue LHS = Result; | |||
14657 | Result.getComplexIntReal() = | |||
14658 | (LHS.getComplexIntReal() * RHS.getComplexIntReal() - | |||
14659 | LHS.getComplexIntImag() * RHS.getComplexIntImag()); | |||
14660 | Result.getComplexIntImag() = | |||
14661 | (LHS.getComplexIntReal() * RHS.getComplexIntImag() + | |||
14662 | LHS.getComplexIntImag() * RHS.getComplexIntReal()); | |||
14663 | } | |||
14664 | break; | |||
14665 | case BO_Div: | |||
14666 | if (Result.isComplexFloat()) { | |||
14667 | // This is an implementation of complex division according to the | |||
14668 | // constraints laid out in C11 Annex G. The implementation uses the | |||
14669 | // following naming scheme: | |||
14670 | // (a + ib) / (c + id) | |||
14671 | ComplexValue LHS = Result; | |||
14672 | APFloat &A = LHS.getComplexFloatReal(); | |||
14673 | APFloat &B = LHS.getComplexFloatImag(); | |||
14674 | APFloat &C = RHS.getComplexFloatReal(); | |||
14675 | APFloat &D = RHS.getComplexFloatImag(); | |||
14676 | APFloat &ResR = Result.getComplexFloatReal(); | |||
14677 | APFloat &ResI = Result.getComplexFloatImag(); | |||
14678 | if (RHSReal) { | |||
14679 | ResR = A / C; | |||
14680 | ResI = B / C; | |||
14681 | } else { | |||
14682 | if (LHSReal) { | |||
14683 | // No real optimizations we can do here, stub out with zero. | |||
14684 | B = APFloat::getZero(A.getSemantics()); | |||
14685 | } | |||
14686 | int DenomLogB = 0; | |||
14687 | APFloat MaxCD = maxnum(abs(C), abs(D)); | |||
14688 | if (MaxCD.isFinite()) { | |||
14689 | DenomLogB = ilogb(MaxCD); | |||
14690 | C = scalbn(C, -DenomLogB, APFloat::rmNearestTiesToEven); | |||
14691 | D = scalbn(D, -DenomLogB, APFloat::rmNearestTiesToEven); | |||
14692 | } | |||
14693 | APFloat Denom = C * C + D * D; | |||
14694 | ResR = scalbn((A * C + B * D) / Denom, -DenomLogB, | |||
14695 | APFloat::rmNearestTiesToEven); | |||
14696 | ResI = scalbn((B * C - A * D) / Denom, -DenomLogB, | |||
14697 | APFloat::rmNearestTiesToEven); | |||
14698 | if (ResR.isNaN() && ResI.isNaN()) { | |||
14699 | if (Denom.isPosZero() && (!A.isNaN() || !B.isNaN())) { | |||
14700 | ResR = APFloat::getInf(ResR.getSemantics(), C.isNegative()) * A; | |||
14701 | ResI = APFloat::getInf(ResR.getSemantics(), C.isNegative()) * B; | |||
14702 | } else if ((A.isInfinity() || B.isInfinity()) && C.isFinite() && | |||
14703 | D.isFinite()) { | |||
14704 | A = APFloat::copySign( | |||
14705 | APFloat(A.getSemantics(), A.isInfinity() ? 1 : 0), A); | |||
14706 | B = APFloat::copySign( | |||
14707 | APFloat(B.getSemantics(), B.isInfinity() ? 1 : 0), B); | |||
14708 | ResR = APFloat::getInf(ResR.getSemantics()) * (A * C + B * D); | |||
14709 | ResI = APFloat::getInf(ResI.getSemantics()) * (B * C - A * D); | |||
14710 | } else if (MaxCD.isInfinity() && A.isFinite() && B.isFinite()) { | |||
14711 | C = APFloat::copySign( | |||
14712 | APFloat(C.getSemantics(), C.isInfinity() ? 1 : 0), C); | |||
14713 | D = APFloat::copySign( | |||
14714 | APFloat(D.getSemantics(), D.isInfinity() ? 1 : 0), D); | |||
14715 | ResR = APFloat::getZero(ResR.getSemantics()) * (A * C + B * D); | |||
14716 | ResI = APFloat::getZero(ResI.getSemantics()) * (B * C - A * D); | |||
14717 | } | |||
14718 | } | |||
14719 | } | |||
14720 | } else { | |||
14721 | if (RHS.getComplexIntReal() == 0 && RHS.getComplexIntImag() == 0) | |||
14722 | return Error(E, diag::note_expr_divide_by_zero); | |||
14723 | ||||
14724 | ComplexValue LHS = Result; | |||
14725 | APSInt Den = RHS.getComplexIntReal() * RHS.getComplexIntReal() + | |||
14726 | RHS.getComplexIntImag() * RHS.getComplexIntImag(); | |||
14727 | Result.getComplexIntReal() = | |||
14728 | (LHS.getComplexIntReal() * RHS.getComplexIntReal() + | |||
14729 | LHS.getComplexIntImag() * RHS.getComplexIntImag()) / Den; | |||
14730 | Result.getComplexIntImag() = | |||
14731 | (LHS.getComplexIntImag() * RHS.getComplexIntReal() - | |||
14732 | LHS.getComplexIntReal() * RHS.getComplexIntImag()) / Den; | |||
14733 | } | |||
14734 | break; | |||
14735 | } | |||
14736 | ||||
14737 | return true; | |||
14738 | } | |||
14739 | ||||
14740 | bool ComplexExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { | |||
14741 | // Get the operand value into 'Result'. | |||
14742 | if (!Visit(E->getSubExpr())) | |||
14743 | return false; | |||
14744 | ||||
14745 | switch (E->getOpcode()) { | |||
14746 | default: | |||
14747 | return Error(E); | |||
14748 | case UO_Extension: | |||
14749 | return true; | |||
14750 | case UO_Plus: | |||
14751 | // The result is always just the subexpr. | |||
14752 | return true; | |||
14753 | case UO_Minus: | |||
14754 | if (Result.isComplexFloat()) { | |||
14755 | Result.getComplexFloatReal().changeSign(); | |||
14756 | Result.getComplexFloatImag().changeSign(); | |||
14757 | } | |||
14758 | else { | |||
14759 | Result.getComplexIntReal() = -Result.getComplexIntReal(); | |||
14760 | Result.getComplexIntImag() = -Result.getComplexIntImag(); | |||
14761 | } | |||
14762 | return true; | |||
14763 | case UO_Not: | |||
14764 | if (Result.isComplexFloat()) | |||
14765 | Result.getComplexFloatImag().changeSign(); | |||
14766 | else | |||
14767 | Result.getComplexIntImag() = -Result.getComplexIntImag(); | |||
14768 | return true; | |||
14769 | } | |||
14770 | } | |||
14771 | ||||
14772 | bool ComplexExprEvaluator::VisitInitListExpr(const InitListExpr *E) { | |||
14773 | if (E->getNumInits() == 2) { | |||
14774 | if (E->getType()->isComplexType()) { | |||
14775 | Result.makeComplexFloat(); | |||
14776 | if (!EvaluateFloat(E->getInit(0), Result.FloatReal, Info)) | |||
14777 | return false; | |||
14778 | if (!EvaluateFloat(E->getInit(1), Result.FloatImag, Info)) | |||
14779 | return false; | |||
14780 | } else { | |||
14781 | Result.makeComplexInt(); | |||
14782 | if (!EvaluateInteger(E->getInit(0), Result.IntReal, Info)) | |||
14783 | return false; | |||
14784 | if (!EvaluateInteger(E->getInit(1), Result.IntImag, Info)) | |||
14785 | return false; | |||
14786 | } | |||
14787 | return true; | |||
14788 | } | |||
14789 | return ExprEvaluatorBaseTy::VisitInitListExpr(E); | |||
14790 | } | |||
14791 | ||||
14792 | bool ComplexExprEvaluator::VisitCallExpr(const CallExpr *E) { | |||
14793 | if (!IsConstantEvaluatedBuiltinCall(E)) | |||
14794 | return ExprEvaluatorBaseTy::VisitCallExpr(E); | |||
14795 | ||||
14796 | switch (E->getBuiltinCallee()) { | |||
14797 | case Builtin::BI__builtin_complex: | |||
14798 | Result.makeComplexFloat(); | |||
14799 | if (!EvaluateFloat(E->getArg(0), Result.FloatReal, Info)) | |||
14800 | return false; | |||
14801 | if (!EvaluateFloat(E->getArg(1), Result.FloatImag, Info)) | |||
14802 | return false; | |||
14803 | return true; | |||
14804 | ||||
14805 | default: | |||
14806 | return false; | |||
14807 | } | |||
14808 | } | |||
14809 | ||||
14810 | //===----------------------------------------------------------------------===// | |||
14811 | // Atomic expression evaluation, essentially just handling the NonAtomicToAtomic | |||
14812 | // implicit conversion. | |||
14813 | //===----------------------------------------------------------------------===// | |||
14814 | ||||
14815 | namespace { | |||
14816 | class AtomicExprEvaluator : | |||
14817 | public ExprEvaluatorBase<AtomicExprEvaluator> { | |||
14818 | const LValue *This; | |||
14819 | APValue &Result; | |||
14820 | public: | |||
14821 | AtomicExprEvaluator(EvalInfo &Info, const LValue *This, APValue &Result) | |||
14822 | : ExprEvaluatorBaseTy(Info), This(This), Result(Result) {} | |||
14823 | ||||
14824 | bool Success(const APValue &V, const Expr *E) { | |||
14825 | Result = V; | |||
14826 | return true; | |||
14827 | } | |||
14828 | ||||
14829 | bool ZeroInitialization(const Expr *E) { | |||
14830 | ImplicitValueInitExpr VIE( | |||
14831 | E->getType()->castAs<AtomicType>()->getValueType()); | |||
14832 | // For atomic-qualified class (and array) types in C++, initialize the | |||
14833 | // _Atomic-wrapped subobject directly, in-place. | |||
14834 | return This ? EvaluateInPlace(Result, Info, *This, &VIE) | |||
14835 | : Evaluate(Result, Info, &VIE); | |||
14836 | } | |||
14837 | ||||
14838 | bool VisitCastExpr(const CastExpr *E) { | |||
14839 | switch (E->getCastKind()) { | |||
14840 | default: | |||
14841 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
14842 | case CK_NullToPointer: | |||
14843 | case CK_NonAtomicToAtomic: | |||
14844 | return This ? EvaluateInPlace(Result, Info, *This, E->getSubExpr()) | |||
14845 | : Evaluate(Result, Info, E->getSubExpr()); | |||
14846 | } | |||
14847 | } | |||
14848 | }; | |||
14849 | } // end anonymous namespace | |||
14850 | ||||
14851 | static bool EvaluateAtomic(const Expr *E, const LValue *This, APValue &Result, | |||
14852 | EvalInfo &Info) { | |||
14853 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 14853, __extension__ __PRETTY_FUNCTION__)); | |||
14854 | assert(E->isPRValue() && E->getType()->isAtomicType())(static_cast <bool> (E->isPRValue() && E-> getType()->isAtomicType()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isAtomicType()" , "clang/lib/AST/ExprConstant.cpp", 14854, __extension__ __PRETTY_FUNCTION__ )); | |||
14855 | return AtomicExprEvaluator(Info, This, Result).Visit(E); | |||
14856 | } | |||
14857 | ||||
14858 | //===----------------------------------------------------------------------===// | |||
14859 | // Void expression evaluation, primarily for a cast to void on the LHS of a | |||
14860 | // comma operator | |||
14861 | //===----------------------------------------------------------------------===// | |||
14862 | ||||
14863 | namespace { | |||
14864 | class VoidExprEvaluator | |||
14865 | : public ExprEvaluatorBase<VoidExprEvaluator> { | |||
14866 | public: | |||
14867 | VoidExprEvaluator(EvalInfo &Info) : ExprEvaluatorBaseTy(Info) {} | |||
14868 | ||||
14869 | bool Success(const APValue &V, const Expr *e) { return true; } | |||
14870 | ||||
14871 | bool ZeroInitialization(const Expr *E) { return true; } | |||
14872 | ||||
14873 | bool VisitCastExpr(const CastExpr *E) { | |||
14874 | switch (E->getCastKind()) { | |||
14875 | default: | |||
14876 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
14877 | case CK_ToVoid: | |||
14878 | VisitIgnoredValue(E->getSubExpr()); | |||
14879 | return true; | |||
14880 | } | |||
14881 | } | |||
14882 | ||||
14883 | bool VisitCallExpr(const CallExpr *E) { | |||
14884 | if (!IsConstantEvaluatedBuiltinCall(E)) | |||
14885 | return ExprEvaluatorBaseTy::VisitCallExpr(E); | |||
14886 | ||||
14887 | switch (E->getBuiltinCallee()) { | |||
14888 | case Builtin::BI__assume: | |||
14889 | case Builtin::BI__builtin_assume: | |||
14890 | // The argument is not evaluated! | |||
14891 | return true; | |||
14892 | ||||
14893 | case Builtin::BI__builtin_operator_delete: | |||
14894 | return HandleOperatorDeleteCall(Info, E); | |||
14895 | ||||
14896 | default: | |||
14897 | return false; | |||
14898 | } | |||
14899 | } | |||
14900 | ||||
14901 | bool VisitCXXDeleteExpr(const CXXDeleteExpr *E); | |||
14902 | }; | |||
14903 | } // end anonymous namespace | |||
14904 | ||||
14905 | bool VoidExprEvaluator::VisitCXXDeleteExpr(const CXXDeleteExpr *E) { | |||
14906 | // We cannot speculatively evaluate a delete expression. | |||
14907 | if (Info.SpeculativeEvaluationDepth) | |||
14908 | return false; | |||
14909 | ||||
14910 | FunctionDecl *OperatorDelete = E->getOperatorDelete(); | |||
14911 | if (!OperatorDelete->isReplaceableGlobalAllocationFunction()) { | |||
14912 | Info.FFDiag(E, diag::note_constexpr_new_non_replaceable) | |||
14913 | << isa<CXXMethodDecl>(OperatorDelete) << OperatorDelete; | |||
14914 | return false; | |||
14915 | } | |||
14916 | ||||
14917 | const Expr *Arg = E->getArgument(); | |||
14918 | ||||
14919 | LValue Pointer; | |||
14920 | if (!EvaluatePointer(Arg, Pointer, Info)) | |||
14921 | return false; | |||
14922 | if (Pointer.Designator.Invalid) | |||
14923 | return false; | |||
14924 | ||||
14925 | // Deleting a null pointer has no effect. | |||
14926 | if (Pointer.isNullPointer()) { | |||
14927 | // This is the only case where we need to produce an extension warning: | |||
14928 | // the only other way we can succeed is if we find a dynamic allocation, | |||
14929 | // and we will have warned when we allocated it in that case. | |||
14930 | if (!Info.getLangOpts().CPlusPlus20) | |||
14931 | Info.CCEDiag(E, diag::note_constexpr_new); | |||
14932 | return true; | |||
14933 | } | |||
14934 | ||||
14935 | std::optional<DynAlloc *> Alloc = CheckDeleteKind( | |||
14936 | Info, E, Pointer, E->isArrayForm() ? DynAlloc::ArrayNew : DynAlloc::New); | |||
14937 | if (!Alloc) | |||
14938 | return false; | |||
14939 | QualType AllocType = Pointer.Base.getDynamicAllocType(); | |||
14940 | ||||
14941 | // For the non-array case, the designator must be empty if the static type | |||
14942 | // does not have a virtual destructor. | |||
14943 | if (!E->isArrayForm() && Pointer.Designator.Entries.size() != 0 && | |||
14944 | !hasVirtualDestructor(Arg->getType()->getPointeeType())) { | |||
14945 | Info.FFDiag(E, diag::note_constexpr_delete_base_nonvirt_dtor) | |||
14946 | << Arg->getType()->getPointeeType() << AllocType; | |||
14947 | return false; | |||
14948 | } | |||
14949 | ||||
14950 | // For a class type with a virtual destructor, the selected operator delete | |||
14951 | // is the one looked up when building the destructor. | |||
14952 | if (!E->isArrayForm() && !E->isGlobalDelete()) { | |||
14953 | const FunctionDecl *VirtualDelete = getVirtualOperatorDelete(AllocType); | |||
14954 | if (VirtualDelete && | |||
14955 | !VirtualDelete->isReplaceableGlobalAllocationFunction()) { | |||
14956 | Info.FFDiag(E, diag::note_constexpr_new_non_replaceable) | |||
14957 | << isa<CXXMethodDecl>(VirtualDelete) << VirtualDelete; | |||
14958 | return false; | |||
14959 | } | |||
14960 | } | |||
14961 | ||||
14962 | if (!HandleDestruction(Info, E->getExprLoc(), Pointer.getLValueBase(), | |||
14963 | (*Alloc)->Value, AllocType)) | |||
14964 | return false; | |||
14965 | ||||
14966 | if (!Info.HeapAllocs.erase(Pointer.Base.dyn_cast<DynamicAllocLValue>())) { | |||
14967 | // The element was already erased. This means the destructor call also | |||
14968 | // deleted the object. | |||
14969 | // FIXME: This probably results in undefined behavior before we get this | |||
14970 | // far, and should be diagnosed elsewhere first. | |||
14971 | Info.FFDiag(E, diag::note_constexpr_double_delete); | |||
14972 | return false; | |||
14973 | } | |||
14974 | ||||
14975 | return true; | |||
14976 | } | |||
14977 | ||||
14978 | static bool EvaluateVoid(const Expr *E, EvalInfo &Info) { | |||
14979 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 14979, __extension__ __PRETTY_FUNCTION__)); | |||
14980 | assert(E->isPRValue() && E->getType()->isVoidType())(static_cast <bool> (E->isPRValue() && E-> getType()->isVoidType()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isVoidType()" , "clang/lib/AST/ExprConstant.cpp", 14980, __extension__ __PRETTY_FUNCTION__ )); | |||
14981 | return VoidExprEvaluator(Info).Visit(E); | |||
14982 | } | |||
14983 | ||||
14984 | //===----------------------------------------------------------------------===// | |||
14985 | // Top level Expr::EvaluateAsRValue method. | |||
14986 | //===----------------------------------------------------------------------===// | |||
14987 | ||||
14988 | static bool Evaluate(APValue &Result, EvalInfo &Info, const Expr *E) { | |||
14989 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 14989, __extension__ __PRETTY_FUNCTION__)); | |||
14990 | // In C, function designators are not lvalues, but we evaluate them as if they | |||
14991 | // are. | |||
14992 | QualType T = E->getType(); | |||
14993 | if (E->isGLValue() || T->isFunctionType()) { | |||
14994 | LValue LV; | |||
14995 | if (!EvaluateLValue(E, LV, Info)) | |||
14996 | return false; | |||
14997 | LV.moveInto(Result); | |||
14998 | } else if (T->isVectorType()) { | |||
14999 | if (!EvaluateVector(E, Result, Info)) | |||
15000 | return false; | |||
15001 | } else if (T->isIntegralOrEnumerationType()) { | |||
15002 | if (!IntExprEvaluator(Info, Result).Visit(E)) | |||
15003 | return false; | |||
15004 | } else if (T->hasPointerRepresentation()) { | |||
15005 | LValue LV; | |||
15006 | if (!EvaluatePointer(E, LV, Info)) | |||
15007 | return false; | |||
15008 | LV.moveInto(Result); | |||
15009 | } else if (T->isRealFloatingType()) { | |||
15010 | llvm::APFloat F(0.0); | |||
15011 | if (!EvaluateFloat(E, F, Info)) | |||
15012 | return false; | |||
15013 | Result = APValue(F); | |||
15014 | } else if (T->isAnyComplexType()) { | |||
15015 | ComplexValue C; | |||
15016 | if (!EvaluateComplex(E, C, Info)) | |||
15017 | return false; | |||
15018 | C.moveInto(Result); | |||
15019 | } else if (T->isFixedPointType()) { | |||
15020 | if (!FixedPointExprEvaluator(Info, Result).Visit(E)) return false; | |||
15021 | } else if (T->isMemberPointerType()) { | |||
15022 | MemberPtr P; | |||
15023 | if (!EvaluateMemberPointer(E, P, Info)) | |||
15024 | return false; | |||
15025 | P.moveInto(Result); | |||
15026 | return true; | |||
15027 | } else if (T->isArrayType()) { | |||
15028 | LValue LV; | |||
15029 | APValue &Value = | |||
15030 | Info.CurrentCall->createTemporary(E, T, ScopeKind::FullExpression, LV); | |||
15031 | if (!EvaluateArray(E, LV, Value, Info)) | |||
15032 | return false; | |||
15033 | Result = Value; | |||
15034 | } else if (T->isRecordType()) { | |||
15035 | LValue LV; | |||
15036 | APValue &Value = | |||
15037 | Info.CurrentCall->createTemporary(E, T, ScopeKind::FullExpression, LV); | |||
15038 | if (!EvaluateRecord(E, LV, Value, Info)) | |||
15039 | return false; | |||
15040 | Result = Value; | |||
15041 | } else if (T->isVoidType()) { | |||
15042 | if (!Info.getLangOpts().CPlusPlus11) | |||
15043 | Info.CCEDiag(E, diag::note_constexpr_nonliteral) | |||
15044 | << E->getType(); | |||
15045 | if (!EvaluateVoid(E, Info)) | |||
15046 | return false; | |||
15047 | } else if (T->isAtomicType()) { | |||
15048 | QualType Unqual = T.getAtomicUnqualifiedType(); | |||
15049 | if (Unqual->isArrayType() || Unqual->isRecordType()) { | |||
15050 | LValue LV; | |||
15051 | APValue &Value = Info.CurrentCall->createTemporary( | |||
15052 | E, Unqual, ScopeKind::FullExpression, LV); | |||
15053 | if (!EvaluateAtomic(E, &LV, Value, Info)) | |||
15054 | return false; | |||
15055 | } else { | |||
15056 | if (!EvaluateAtomic(E, nullptr, Result, Info)) | |||
15057 | return false; | |||
15058 | } | |||
15059 | } else if (Info.getLangOpts().CPlusPlus11) { | |||
15060 | Info.FFDiag(E, diag::note_constexpr_nonliteral) << E->getType(); | |||
15061 | return false; | |||
15062 | } else { | |||
15063 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
15064 | return false; | |||
15065 | } | |||
15066 | ||||
15067 | return true; | |||
15068 | } | |||
15069 | ||||
15070 | /// EvaluateInPlace - Evaluate an expression in-place in an APValue. In some | |||
15071 | /// cases, the in-place evaluation is essential, since later initializers for | |||
15072 | /// an object can indirectly refer to subobjects which were initialized earlier. | |||
15073 | static bool EvaluateInPlace(APValue &Result, EvalInfo &Info, const LValue &This, | |||
15074 | const Expr *E, bool AllowNonLiteralTypes) { | |||
15075 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 15075, __extension__ __PRETTY_FUNCTION__)); | |||
15076 | ||||
15077 | if (!AllowNonLiteralTypes && !CheckLiteralType(Info, E, &This)) | |||
15078 | return false; | |||
15079 | ||||
15080 | if (E->isPRValue()) { | |||
15081 | // Evaluate arrays and record types in-place, so that later initializers can | |||
15082 | // refer to earlier-initialized members of the object. | |||
15083 | QualType T = E->getType(); | |||
15084 | if (T->isArrayType()) | |||
15085 | return EvaluateArray(E, This, Result, Info); | |||
15086 | else if (T->isRecordType()) | |||
15087 | return EvaluateRecord(E, This, Result, Info); | |||
15088 | else if (T->isAtomicType()) { | |||
15089 | QualType Unqual = T.getAtomicUnqualifiedType(); | |||
15090 | if (Unqual->isArrayType() || Unqual->isRecordType()) | |||
15091 | return EvaluateAtomic(E, &This, Result, Info); | |||
15092 | } | |||
15093 | } | |||
15094 | ||||
15095 | // For any other type, in-place evaluation is unimportant. | |||
15096 | return Evaluate(Result, Info, E); | |||
15097 | } | |||
15098 | ||||
15099 | /// EvaluateAsRValue - Try to evaluate this expression, performing an implicit | |||
15100 | /// lvalue-to-rvalue cast if it is an lvalue. | |||
15101 | static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result) { | |||
15102 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 15102, __extension__ __PRETTY_FUNCTION__)); | |||
15103 | ||||
15104 | if (E->getType().isNull()) | |||
15105 | return false; | |||
15106 | ||||
15107 | if (!CheckLiteralType(Info, E)) | |||
15108 | return false; | |||
15109 | ||||
15110 | if (Info.EnableNewConstInterp) { | |||
15111 | if (!Info.Ctx.getInterpContext().evaluateAsRValue(Info, E, Result)) | |||
15112 | return false; | |||
15113 | } else { | |||
15114 | if (!::Evaluate(Result, Info, E)) | |||
15115 | return false; | |||
15116 | } | |||
15117 | ||||
15118 | // Implicit lvalue-to-rvalue cast. | |||
15119 | if (E->isGLValue()) { | |||
15120 | LValue LV; | |||
15121 | LV.setFrom(Info.Ctx, Result); | |||
15122 | if (!handleLValueToRValueConversion(Info, E, E->getType(), LV, Result)) | |||
15123 | return false; | |||
15124 | } | |||
15125 | ||||
15126 | // Check this core constant expression is a constant expression. | |||
15127 | return CheckConstantExpression(Info, E->getExprLoc(), E->getType(), Result, | |||
15128 | ConstantExprKind::Normal) && | |||
15129 | CheckMemoryLeaks(Info); | |||
15130 | } | |||
15131 | ||||
15132 | static bool FastEvaluateAsRValue(const Expr *Exp, Expr::EvalResult &Result, | |||
15133 | const ASTContext &Ctx, bool &IsConst) { | |||
15134 | // Fast-path evaluations of integer literals, since we sometimes see files | |||
15135 | // containing vast quantities of these. | |||
15136 | if (const IntegerLiteral *L = dyn_cast<IntegerLiteral>(Exp)) { | |||
15137 | Result.Val = APValue(APSInt(L->getValue(), | |||
15138 | L->getType()->isUnsignedIntegerType())); | |||
15139 | IsConst = true; | |||
15140 | return true; | |||
15141 | } | |||
15142 | ||||
15143 | if (const auto *L = dyn_cast<CXXBoolLiteralExpr>(Exp)) { | |||
15144 | Result.Val = APValue(APSInt(APInt(1, L->getValue()))); | |||
15145 | IsConst = true; | |||
15146 | return true; | |||
15147 | } | |||
15148 | ||||
15149 | // This case should be rare, but we need to check it before we check on | |||
15150 | // the type below. | |||
15151 | if (Exp->getType().isNull()) { | |||
15152 | IsConst = false; | |||
15153 | return true; | |||
15154 | } | |||
15155 | ||||
15156 | // FIXME: Evaluating values of large array and record types can cause | |||
15157 | // performance problems. Only do so in C++11 for now. | |||
15158 | if (Exp->isPRValue() && | |||
15159 | (Exp->getType()->isArrayType() || Exp->getType()->isRecordType()) && | |||
15160 | !Ctx.getLangOpts().CPlusPlus11) { | |||
15161 | IsConst = false; | |||
15162 | return true; | |||
15163 | } | |||
15164 | return false; | |||
15165 | } | |||
15166 | ||||
15167 | static bool hasUnacceptableSideEffect(Expr::EvalStatus &Result, | |||
15168 | Expr::SideEffectsKind SEK) { | |||
15169 | return (SEK < Expr::SE_AllowSideEffects && Result.HasSideEffects) || | |||
15170 | (SEK < Expr::SE_AllowUndefinedBehavior && Result.HasUndefinedBehavior); | |||
15171 | } | |||
15172 | ||||
15173 | static bool EvaluateAsRValue(const Expr *E, Expr::EvalResult &Result, | |||
15174 | const ASTContext &Ctx, EvalInfo &Info) { | |||
15175 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 15175, __extension__ __PRETTY_FUNCTION__)); | |||
15176 | bool IsConst; | |||
15177 | if (FastEvaluateAsRValue(E, Result, Ctx, IsConst)) | |||
15178 | return IsConst; | |||
15179 | ||||
15180 | return EvaluateAsRValue(Info, E, Result.Val); | |||
15181 | } | |||
15182 | ||||
15183 | static bool EvaluateAsInt(const Expr *E, Expr::EvalResult &ExprResult, | |||
15184 | const ASTContext &Ctx, | |||
15185 | Expr::SideEffectsKind AllowSideEffects, | |||
15186 | EvalInfo &Info) { | |||
15187 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 15187, __extension__ __PRETTY_FUNCTION__)); | |||
15188 | if (!E->getType()->isIntegralOrEnumerationType()) | |||
15189 | return false; | |||
15190 | ||||
15191 | if (!::EvaluateAsRValue(E, ExprResult, Ctx, Info) || | |||
15192 | !ExprResult.Val.isInt() || | |||
15193 | hasUnacceptableSideEffect(ExprResult, AllowSideEffects)) | |||
15194 | return false; | |||
15195 | ||||
15196 | return true; | |||
15197 | } | |||
15198 | ||||
15199 | static bool EvaluateAsFixedPoint(const Expr *E, Expr::EvalResult &ExprResult, | |||
15200 | const ASTContext &Ctx, | |||
15201 | Expr::SideEffectsKind AllowSideEffects, | |||
15202 | EvalInfo &Info) { | |||
15203 | assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void ( 0) : __assert_fail ("!E->isValueDependent()", "clang/lib/AST/ExprConstant.cpp" , 15203, __extension__ __PRETTY_FUNCTION__)); | |||
15204 | if (!E->getType()->isFixedPointType()) | |||
15205 | return false; | |||
15206 | ||||
15207 | if (!::EvaluateAsRValue(E, ExprResult, Ctx, Info)) | |||
15208 | return false; | |||
15209 | ||||
15210 | if (!ExprResult.Val.isFixedPoint() || | |||
15211 | hasUnacceptableSideEffect(ExprResult, AllowSideEffects)) | |||
15212 | return false; | |||
15213 | ||||
15214 | return true; | |||
15215 | } | |||
15216 | ||||
15217 | /// EvaluateAsRValue - Return true if this is a constant which we can fold using | |||
15218 | /// any crazy technique (that has nothing to do with language standards) that | |||
15219 | /// we want to. If this function returns true, it returns the folded constant | |||
15220 | /// in Result. If this expression is a glvalue, an lvalue-to-rvalue conversion | |||
15221 | /// will be applied to the result. | |||
15222 | bool Expr::EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx, | |||
15223 | bool InConstantContext) const { | |||
15224 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15225, __extension__ __PRETTY_FUNCTION__ )) | |||
15225 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15225, __extension__ __PRETTY_FUNCTION__ )); | |||
15226 | ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateAsRValue"); | |||
15227 | EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects); | |||
15228 | Info.InConstantContext = InConstantContext; | |||
15229 | return ::EvaluateAsRValue(this, Result, Ctx, Info); | |||
15230 | } | |||
15231 | ||||
15232 | bool Expr::EvaluateAsBooleanCondition(bool &Result, const ASTContext &Ctx, | |||
15233 | bool InConstantContext) const { | |||
15234 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15235, __extension__ __PRETTY_FUNCTION__ )) | |||
15235 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15235, __extension__ __PRETTY_FUNCTION__ )); | |||
15236 | ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateAsBooleanCondition"); | |||
15237 | EvalResult Scratch; | |||
15238 | return EvaluateAsRValue(Scratch, Ctx, InConstantContext) && | |||
15239 | HandleConversionToBool(Scratch.Val, Result); | |||
15240 | } | |||
15241 | ||||
15242 | bool Expr::EvaluateAsInt(EvalResult &Result, const ASTContext &Ctx, | |||
15243 | SideEffectsKind AllowSideEffects, | |||
15244 | bool InConstantContext) const { | |||
15245 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15246, __extension__ __PRETTY_FUNCTION__ )) | |||
15246 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15246, __extension__ __PRETTY_FUNCTION__ )); | |||
15247 | ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateAsInt"); | |||
15248 | EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects); | |||
15249 | Info.InConstantContext = InConstantContext; | |||
15250 | return ::EvaluateAsInt(this, Result, Ctx, AllowSideEffects, Info); | |||
15251 | } | |||
15252 | ||||
15253 | bool Expr::EvaluateAsFixedPoint(EvalResult &Result, const ASTContext &Ctx, | |||
15254 | SideEffectsKind AllowSideEffects, | |||
15255 | bool InConstantContext) const { | |||
15256 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15257, __extension__ __PRETTY_FUNCTION__ )) | |||
15257 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15257, __extension__ __PRETTY_FUNCTION__ )); | |||
15258 | ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateAsFixedPoint"); | |||
15259 | EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects); | |||
15260 | Info.InConstantContext = InConstantContext; | |||
15261 | return ::EvaluateAsFixedPoint(this, Result, Ctx, AllowSideEffects, Info); | |||
15262 | } | |||
15263 | ||||
15264 | bool Expr::EvaluateAsFloat(APFloat &Result, const ASTContext &Ctx, | |||
15265 | SideEffectsKind AllowSideEffects, | |||
15266 | bool InConstantContext) const { | |||
15267 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15268, __extension__ __PRETTY_FUNCTION__ )) | |||
15268 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15268, __extension__ __PRETTY_FUNCTION__ )); | |||
15269 | ||||
15270 | if (!getType()->isRealFloatingType()) | |||
15271 | return false; | |||
15272 | ||||
15273 | ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateAsFloat"); | |||
15274 | EvalResult ExprResult; | |||
15275 | if (!EvaluateAsRValue(ExprResult, Ctx, InConstantContext) || | |||
15276 | !ExprResult.Val.isFloat() || | |||
15277 | hasUnacceptableSideEffect(ExprResult, AllowSideEffects)) | |||
15278 | return false; | |||
15279 | ||||
15280 | Result = ExprResult.Val.getFloat(); | |||
15281 | return true; | |||
15282 | } | |||
15283 | ||||
15284 | bool Expr::EvaluateAsLValue(EvalResult &Result, const ASTContext &Ctx, | |||
15285 | bool InConstantContext) const { | |||
15286 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15287, __extension__ __PRETTY_FUNCTION__ )) | |||
15287 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15287, __extension__ __PRETTY_FUNCTION__ )); | |||
15288 | ||||
15289 | ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateAsLValue"); | |||
15290 | EvalInfo Info(Ctx, Result, EvalInfo::EM_ConstantFold); | |||
15291 | Info.InConstantContext = InConstantContext; | |||
15292 | LValue LV; | |||
15293 | CheckedTemporaries CheckedTemps; | |||
15294 | if (!EvaluateLValue(this, LV, Info) || !Info.discardCleanups() || | |||
15295 | Result.HasSideEffects || | |||
15296 | !CheckLValueConstantExpression(Info, getExprLoc(), | |||
15297 | Ctx.getLValueReferenceType(getType()), LV, | |||
15298 | ConstantExprKind::Normal, CheckedTemps)) | |||
15299 | return false; | |||
15300 | ||||
15301 | LV.moveInto(Result.Val); | |||
15302 | return true; | |||
15303 | } | |||
15304 | ||||
15305 | static bool EvaluateDestruction(const ASTContext &Ctx, APValue::LValueBase Base, | |||
15306 | APValue DestroyedValue, QualType Type, | |||
15307 | SourceLocation Loc, Expr::EvalStatus &EStatus, | |||
15308 | bool IsConstantDestruction) { | |||
15309 | EvalInfo Info(Ctx, EStatus, | |||
15310 | IsConstantDestruction ? EvalInfo::EM_ConstantExpression | |||
15311 | : EvalInfo::EM_ConstantFold); | |||
15312 | Info.setEvaluatingDecl(Base, DestroyedValue, | |||
15313 | EvalInfo::EvaluatingDeclKind::Dtor); | |||
15314 | Info.InConstantContext = IsConstantDestruction; | |||
15315 | ||||
15316 | LValue LVal; | |||
15317 | LVal.set(Base); | |||
15318 | ||||
15319 | if (!HandleDestruction(Info, Loc, Base, DestroyedValue, Type) || | |||
15320 | EStatus.HasSideEffects) | |||
15321 | return false; | |||
15322 | ||||
15323 | if (!Info.discardCleanups()) | |||
15324 | llvm_unreachable("Unhandled cleanup; missing full expression marker?")::llvm::llvm_unreachable_internal("Unhandled cleanup; missing full expression marker?" , "clang/lib/AST/ExprConstant.cpp", 15324); | |||
15325 | ||||
15326 | return true; | |||
15327 | } | |||
15328 | ||||
15329 | bool Expr::EvaluateAsConstantExpr(EvalResult &Result, const ASTContext &Ctx, | |||
15330 | ConstantExprKind Kind) const { | |||
15331 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15332, __extension__ __PRETTY_FUNCTION__ )) | |||
15332 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15332, __extension__ __PRETTY_FUNCTION__ )); | |||
15333 | bool IsConst; | |||
15334 | if (FastEvaluateAsRValue(this, Result, Ctx, IsConst) && Result.Val.hasValue()) | |||
15335 | return true; | |||
15336 | ||||
15337 | ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateAsConstantExpr"); | |||
15338 | EvalInfo::EvaluationMode EM = EvalInfo::EM_ConstantExpression; | |||
15339 | EvalInfo Info(Ctx, Result, EM); | |||
15340 | Info.InConstantContext = true; | |||
15341 | ||||
15342 | // The type of the object we're initializing is 'const T' for a class NTTP. | |||
15343 | QualType T = getType(); | |||
15344 | if (Kind == ConstantExprKind::ClassTemplateArgument) | |||
15345 | T.addConst(); | |||
15346 | ||||
15347 | // If we're evaluating a prvalue, fake up a MaterializeTemporaryExpr to | |||
15348 | // represent the result of the evaluation. CheckConstantExpression ensures | |||
15349 | // this doesn't escape. | |||
15350 | MaterializeTemporaryExpr BaseMTE(T, const_cast<Expr*>(this), true); | |||
15351 | APValue::LValueBase Base(&BaseMTE); | |||
15352 | ||||
15353 | Info.setEvaluatingDecl(Base, Result.Val); | |||
15354 | LValue LVal; | |||
15355 | LVal.set(Base); | |||
15356 | ||||
15357 | { | |||
15358 | // C++23 [intro.execution]/p5 | |||
15359 | // A full-expression is [...] a constant-expression | |||
15360 | // So we need to make sure temporary objects are destroyed after having | |||
15361 | // evaluating the expression (per C++23 [class.temporary]/p4). | |||
15362 | FullExpressionRAII Scope(Info); | |||
15363 | if (!::EvaluateInPlace(Result.Val, Info, LVal, this) || | |||
15364 | Result.HasSideEffects || !Scope.destroy()) | |||
15365 | return false; | |||
15366 | } | |||
15367 | ||||
15368 | if (!Info.discardCleanups()) | |||
15369 | llvm_unreachable("Unhandled cleanup; missing full expression marker?")::llvm::llvm_unreachable_internal("Unhandled cleanup; missing full expression marker?" , "clang/lib/AST/ExprConstant.cpp", 15369); | |||
15370 | ||||
15371 | if (!CheckConstantExpression(Info, getExprLoc(), getStorageType(Ctx, this), | |||
15372 | Result.Val, Kind)) | |||
15373 | return false; | |||
15374 | if (!CheckMemoryLeaks(Info)) | |||
15375 | return false; | |||
15376 | ||||
15377 | // If this is a class template argument, it's required to have constant | |||
15378 | // destruction too. | |||
15379 | if (Kind == ConstantExprKind::ClassTemplateArgument && | |||
15380 | (!EvaluateDestruction(Ctx, Base, Result.Val, T, getBeginLoc(), Result, | |||
15381 | true) || | |||
15382 | Result.HasSideEffects)) { | |||
15383 | // FIXME: Prefix a note to indicate that the problem is lack of constant | |||
15384 | // destruction. | |||
15385 | return false; | |||
15386 | } | |||
15387 | ||||
15388 | return true; | |||
15389 | } | |||
15390 | ||||
15391 | bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx, | |||
15392 | const VarDecl *VD, | |||
15393 | SmallVectorImpl<PartialDiagnosticAt> &Notes, | |||
15394 | bool IsConstantInitialization) const { | |||
15395 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15396, __extension__ __PRETTY_FUNCTION__ )) | |||
15396 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15396, __extension__ __PRETTY_FUNCTION__ )); | |||
15397 | ||||
15398 | llvm::TimeTraceScope TimeScope("EvaluateAsInitializer", [&] { | |||
15399 | std::string Name; | |||
15400 | llvm::raw_string_ostream OS(Name); | |||
15401 | VD->printQualifiedName(OS); | |||
15402 | return Name; | |||
15403 | }); | |||
15404 | ||||
15405 | // FIXME: Evaluating initializers for large array and record types can cause | |||
15406 | // performance problems. Only do so in C++11 for now. | |||
15407 | if (isPRValue() && (getType()->isArrayType() || getType()->isRecordType()) && | |||
15408 | !Ctx.getLangOpts().CPlusPlus11) | |||
15409 | return false; | |||
15410 | ||||
15411 | Expr::EvalStatus EStatus; | |||
15412 | EStatus.Diag = &Notes; | |||
15413 | ||||
15414 | EvalInfo Info(Ctx, EStatus, | |||
15415 | (IsConstantInitialization && Ctx.getLangOpts().CPlusPlus11) | |||
15416 | ? EvalInfo::EM_ConstantExpression | |||
15417 | : EvalInfo::EM_ConstantFold); | |||
15418 | Info.setEvaluatingDecl(VD, Value); | |||
15419 | Info.InConstantContext = IsConstantInitialization; | |||
15420 | ||||
15421 | SourceLocation DeclLoc = VD->getLocation(); | |||
15422 | QualType DeclTy = VD->getType(); | |||
15423 | ||||
15424 | if (Info.EnableNewConstInterp) { | |||
15425 | auto &InterpCtx = const_cast<ASTContext &>(Ctx).getInterpContext(); | |||
15426 | if (!InterpCtx.evaluateAsInitializer(Info, VD, Value)) | |||
15427 | return false; | |||
15428 | } else { | |||
15429 | LValue LVal; | |||
15430 | LVal.set(VD); | |||
15431 | ||||
15432 | if (!EvaluateInPlace(Value, Info, LVal, this, | |||
15433 | /*AllowNonLiteralTypes=*/true) || | |||
15434 | EStatus.HasSideEffects) | |||
15435 | return false; | |||
15436 | ||||
15437 | // At this point, any lifetime-extended temporaries are completely | |||
15438 | // initialized. | |||
15439 | Info.performLifetimeExtension(); | |||
15440 | ||||
15441 | if (!Info.discardCleanups()) | |||
15442 | llvm_unreachable("Unhandled cleanup; missing full expression marker?")::llvm::llvm_unreachable_internal("Unhandled cleanup; missing full expression marker?" , "clang/lib/AST/ExprConstant.cpp", 15442); | |||
15443 | } | |||
15444 | return CheckConstantExpression(Info, DeclLoc, DeclTy, Value, | |||
15445 | ConstantExprKind::Normal) && | |||
15446 | CheckMemoryLeaks(Info); | |||
15447 | } | |||
15448 | ||||
15449 | bool VarDecl::evaluateDestruction( | |||
15450 | SmallVectorImpl<PartialDiagnosticAt> &Notes) const { | |||
15451 | Expr::EvalStatus EStatus; | |||
15452 | EStatus.Diag = &Notes; | |||
15453 | ||||
15454 | // Only treat the destruction as constant destruction if we formally have | |||
15455 | // constant initialization (or are usable in a constant expression). | |||
15456 | bool IsConstantDestruction = hasConstantInitialization(); | |||
15457 | ||||
15458 | // Make a copy of the value for the destructor to mutate, if we know it. | |||
15459 | // Otherwise, treat the value as default-initialized; if the destructor works | |||
15460 | // anyway, then the destruction is constant (and must be essentially empty). | |||
15461 | APValue DestroyedValue; | |||
15462 | if (getEvaluatedValue() && !getEvaluatedValue()->isAbsent()) | |||
15463 | DestroyedValue = *getEvaluatedValue(); | |||
15464 | else if (!getDefaultInitValue(getType(), DestroyedValue)) | |||
15465 | return false; | |||
15466 | ||||
15467 | if (!EvaluateDestruction(getASTContext(), this, std::move(DestroyedValue), | |||
15468 | getType(), getLocation(), EStatus, | |||
15469 | IsConstantDestruction) || | |||
15470 | EStatus.HasSideEffects) | |||
15471 | return false; | |||
15472 | ||||
15473 | ensureEvaluatedStmt()->HasConstantDestruction = true; | |||
15474 | return true; | |||
15475 | } | |||
15476 | ||||
15477 | /// isEvaluatable - Call EvaluateAsRValue to see if this expression can be | |||
15478 | /// constant folded, but discard the result. | |||
15479 | bool Expr::isEvaluatable(const ASTContext &Ctx, SideEffectsKind SEK) const { | |||
15480 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15481, __extension__ __PRETTY_FUNCTION__ )) | |||
15481 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15481, __extension__ __PRETTY_FUNCTION__ )); | |||
15482 | ||||
15483 | EvalResult Result; | |||
15484 | return EvaluateAsRValue(Result, Ctx, /* in constant context */ true) && | |||
15485 | !hasUnacceptableSideEffect(Result, SEK); | |||
15486 | } | |||
15487 | ||||
15488 | APSInt Expr::EvaluateKnownConstInt(const ASTContext &Ctx, | |||
15489 | SmallVectorImpl<PartialDiagnosticAt> *Diag) const { | |||
15490 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15491, __extension__ __PRETTY_FUNCTION__ )) | |||
15491 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15491, __extension__ __PRETTY_FUNCTION__ )); | |||
15492 | ||||
15493 | ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateKnownConstInt"); | |||
15494 | EvalResult EVResult; | |||
15495 | EVResult.Diag = Diag; | |||
15496 | EvalInfo Info(Ctx, EVResult, EvalInfo::EM_IgnoreSideEffects); | |||
15497 | Info.InConstantContext = true; | |||
15498 | ||||
15499 | bool Result = ::EvaluateAsRValue(this, EVResult, Ctx, Info); | |||
15500 | (void)Result; | |||
15501 | assert(Result && "Could not evaluate expression")(static_cast <bool> (Result && "Could not evaluate expression" ) ? void (0) : __assert_fail ("Result && \"Could not evaluate expression\"" , "clang/lib/AST/ExprConstant.cpp", 15501, __extension__ __PRETTY_FUNCTION__ )); | |||
15502 | assert(EVResult.Val.isInt() && "Expression did not evaluate to integer")(static_cast <bool> (EVResult.Val.isInt() && "Expression did not evaluate to integer" ) ? void (0) : __assert_fail ("EVResult.Val.isInt() && \"Expression did not evaluate to integer\"" , "clang/lib/AST/ExprConstant.cpp", 15502, __extension__ __PRETTY_FUNCTION__ )); | |||
15503 | ||||
15504 | return EVResult.Val.getInt(); | |||
15505 | } | |||
15506 | ||||
15507 | APSInt Expr::EvaluateKnownConstIntCheckOverflow( | |||
15508 | const ASTContext &Ctx, SmallVectorImpl<PartialDiagnosticAt> *Diag) const { | |||
15509 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15510, __extension__ __PRETTY_FUNCTION__ )) | |||
15510 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15510, __extension__ __PRETTY_FUNCTION__ )); | |||
15511 | ||||
15512 | ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateKnownConstIntCheckOverflow"); | |||
15513 | EvalResult EVResult; | |||
15514 | EVResult.Diag = Diag; | |||
15515 | EvalInfo Info(Ctx, EVResult, EvalInfo::EM_IgnoreSideEffects); | |||
15516 | Info.InConstantContext = true; | |||
15517 | Info.CheckingForUndefinedBehavior = true; | |||
15518 | ||||
15519 | bool Result = ::EvaluateAsRValue(Info, this, EVResult.Val); | |||
15520 | (void)Result; | |||
15521 | assert(Result && "Could not evaluate expression")(static_cast <bool> (Result && "Could not evaluate expression" ) ? void (0) : __assert_fail ("Result && \"Could not evaluate expression\"" , "clang/lib/AST/ExprConstant.cpp", 15521, __extension__ __PRETTY_FUNCTION__ )); | |||
15522 | assert(EVResult.Val.isInt() && "Expression did not evaluate to integer")(static_cast <bool> (EVResult.Val.isInt() && "Expression did not evaluate to integer" ) ? void (0) : __assert_fail ("EVResult.Val.isInt() && \"Expression did not evaluate to integer\"" , "clang/lib/AST/ExprConstant.cpp", 15522, __extension__ __PRETTY_FUNCTION__ )); | |||
15523 | ||||
15524 | return EVResult.Val.getInt(); | |||
15525 | } | |||
15526 | ||||
15527 | void Expr::EvaluateForOverflow(const ASTContext &Ctx) const { | |||
15528 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15529, __extension__ __PRETTY_FUNCTION__ )) | |||
15529 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 15529, __extension__ __PRETTY_FUNCTION__ )); | |||
15530 | ||||
15531 | ExprTimeTraceScope TimeScope(this, Ctx, "EvaluateForOverflow"); | |||
15532 | bool IsConst; | |||
15533 | EvalResult EVResult; | |||
15534 | if (!FastEvaluateAsRValue(this, EVResult, Ctx, IsConst)) { | |||
15535 | EvalInfo Info(Ctx, EVResult, EvalInfo::EM_IgnoreSideEffects); | |||
15536 | Info.CheckingForUndefinedBehavior = true; | |||
15537 | (void)::EvaluateAsRValue(Info, this, EVResult.Val); | |||
15538 | } | |||
15539 | } | |||
15540 | ||||
15541 | bool Expr::EvalResult::isGlobalLValue() const { | |||
15542 | assert(Val.isLValue())(static_cast <bool> (Val.isLValue()) ? void (0) : __assert_fail ("Val.isLValue()", "clang/lib/AST/ExprConstant.cpp", 15542, __extension__ __PRETTY_FUNCTION__)); | |||
15543 | return IsGlobalLValue(Val.getLValueBase()); | |||
15544 | } | |||
15545 | ||||
15546 | /// isIntegerConstantExpr - this recursive routine will test if an expression is | |||
15547 | /// an integer constant expression. | |||
15548 | ||||
15549 | /// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero, | |||
15550 | /// comma, etc | |||
15551 | ||||
15552 | // CheckICE - This function does the fundamental ICE checking: the returned | |||
15553 | // ICEDiag contains an ICEKind indicating whether the expression is an ICE, | |||
15554 | // and a (possibly null) SourceLocation indicating the location of the problem. | |||
15555 | // | |||
15556 | // Note that to reduce code duplication, this helper does no evaluation | |||
15557 | // itself; the caller checks whether the expression is evaluatable, and | |||
15558 | // in the rare cases where CheckICE actually cares about the evaluated | |||
15559 | // value, it calls into Evaluate. | |||
15560 | ||||
15561 | namespace { | |||
15562 | ||||
15563 | enum ICEKind { | |||
15564 | /// This expression is an ICE. | |||
15565 | IK_ICE, | |||
15566 | /// This expression is not an ICE, but if it isn't evaluated, it's | |||
15567 | /// a legal subexpression for an ICE. This return value is used to handle | |||
15568 | /// the comma operator in C99 mode, and non-constant subexpressions. | |||
15569 | IK_ICEIfUnevaluated, | |||
15570 | /// This expression is not an ICE, and is not a legal subexpression for one. | |||
15571 | IK_NotICE | |||
15572 | }; | |||
15573 | ||||
15574 | struct ICEDiag { | |||
15575 | ICEKind Kind; | |||
15576 | SourceLocation Loc; | |||
15577 | ||||
15578 | ICEDiag(ICEKind IK, SourceLocation l) : Kind(IK), Loc(l) {} | |||
15579 | }; | |||
15580 | ||||
15581 | } | |||
15582 | ||||
15583 | static ICEDiag NoDiag() { return ICEDiag(IK_ICE, SourceLocation()); } | |||
15584 | ||||
15585 | static ICEDiag Worst(ICEDiag A, ICEDiag B) { return A.Kind >= B.Kind ? A : B; } | |||
15586 | ||||
15587 | static ICEDiag CheckEvalInICE(const Expr* E, const ASTContext &Ctx) { | |||
15588 | Expr::EvalResult EVResult; | |||
15589 | Expr::EvalStatus Status; | |||
15590 | EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpression); | |||
15591 | ||||
15592 | Info.InConstantContext = true; | |||
15593 | if (!::EvaluateAsRValue(E, EVResult, Ctx, Info) || EVResult.HasSideEffects || | |||
15594 | !EVResult.Val.isInt()) | |||
15595 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15596 | ||||
15597 | return NoDiag(); | |||
15598 | } | |||
15599 | ||||
15600 | static ICEDiag CheckICE(const Expr* E, const ASTContext &Ctx) { | |||
15601 | assert(!E->isValueDependent() && "Should not see value dependent exprs!")(static_cast <bool> (!E->isValueDependent() && "Should not see value dependent exprs!") ? void (0) : __assert_fail ("!E->isValueDependent() && \"Should not see value dependent exprs!\"" , "clang/lib/AST/ExprConstant.cpp", 15601, __extension__ __PRETTY_FUNCTION__ )); | |||
15602 | if (!E->getType()->isIntegralOrEnumerationType()) | |||
15603 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15604 | ||||
15605 | switch (E->getStmtClass()) { | |||
15606 | #define ABSTRACT_STMT(Node) | |||
15607 | #define STMT(Node, Base) case Expr::Node##Class: | |||
15608 | #define EXPR(Node, Base) | |||
15609 | #include "clang/AST/StmtNodes.inc" | |||
15610 | case Expr::PredefinedExprClass: | |||
15611 | case Expr::FloatingLiteralClass: | |||
15612 | case Expr::ImaginaryLiteralClass: | |||
15613 | case Expr::StringLiteralClass: | |||
15614 | case Expr::ArraySubscriptExprClass: | |||
15615 | case Expr::MatrixSubscriptExprClass: | |||
15616 | case Expr::OMPArraySectionExprClass: | |||
15617 | case Expr::OMPArrayShapingExprClass: | |||
15618 | case Expr::OMPIteratorExprClass: | |||
15619 | case Expr::MemberExprClass: | |||
15620 | case Expr::CompoundAssignOperatorClass: | |||
15621 | case Expr::CompoundLiteralExprClass: | |||
15622 | case Expr::ExtVectorElementExprClass: | |||
15623 | case Expr::DesignatedInitExprClass: | |||
15624 | case Expr::ArrayInitLoopExprClass: | |||
15625 | case Expr::ArrayInitIndexExprClass: | |||
15626 | case Expr::NoInitExprClass: | |||
15627 | case Expr::DesignatedInitUpdateExprClass: | |||
15628 | case Expr::ImplicitValueInitExprClass: | |||
15629 | case Expr::ParenListExprClass: | |||
15630 | case Expr::VAArgExprClass: | |||
15631 | case Expr::AddrLabelExprClass: | |||
15632 | case Expr::StmtExprClass: | |||
15633 | case Expr::CXXMemberCallExprClass: | |||
15634 | case Expr::CUDAKernelCallExprClass: | |||
15635 | case Expr::CXXAddrspaceCastExprClass: | |||
15636 | case Expr::CXXDynamicCastExprClass: | |||
15637 | case Expr::CXXTypeidExprClass: | |||
15638 | case Expr::CXXUuidofExprClass: | |||
15639 | case Expr::MSPropertyRefExprClass: | |||
15640 | case Expr::MSPropertySubscriptExprClass: | |||
15641 | case Expr::CXXNullPtrLiteralExprClass: | |||
15642 | case Expr::UserDefinedLiteralClass: | |||
15643 | case Expr::CXXThisExprClass: | |||
15644 | case Expr::CXXThrowExprClass: | |||
15645 | case Expr::CXXNewExprClass: | |||
15646 | case Expr::CXXDeleteExprClass: | |||
15647 | case Expr::CXXPseudoDestructorExprClass: | |||
15648 | case Expr::UnresolvedLookupExprClass: | |||
15649 | case Expr::TypoExprClass: | |||
15650 | case Expr::RecoveryExprClass: | |||
15651 | case Expr::DependentScopeDeclRefExprClass: | |||
15652 | case Expr::CXXConstructExprClass: | |||
15653 | case Expr::CXXInheritedCtorInitExprClass: | |||
15654 | case Expr::CXXStdInitializerListExprClass: | |||
15655 | case Expr::CXXBindTemporaryExprClass: | |||
15656 | case Expr::ExprWithCleanupsClass: | |||
15657 | case Expr::CXXTemporaryObjectExprClass: | |||
15658 | case Expr::CXXUnresolvedConstructExprClass: | |||
15659 | case Expr::CXXDependentScopeMemberExprClass: | |||
15660 | case Expr::UnresolvedMemberExprClass: | |||
15661 | case Expr::ObjCStringLiteralClass: | |||
15662 | case Expr::ObjCBoxedExprClass: | |||
15663 | case Expr::ObjCArrayLiteralClass: | |||
15664 | case Expr::ObjCDictionaryLiteralClass: | |||
15665 | case Expr::ObjCEncodeExprClass: | |||
15666 | case Expr::ObjCMessageExprClass: | |||
15667 | case Expr::ObjCSelectorExprClass: | |||
15668 | case Expr::ObjCProtocolExprClass: | |||
15669 | case Expr::ObjCIvarRefExprClass: | |||
15670 | case Expr::ObjCPropertyRefExprClass: | |||
15671 | case Expr::ObjCSubscriptRefExprClass: | |||
15672 | case Expr::ObjCIsaExprClass: | |||
15673 | case Expr::ObjCAvailabilityCheckExprClass: | |||
15674 | case Expr::ShuffleVectorExprClass: | |||
15675 | case Expr::ConvertVectorExprClass: | |||
15676 | case Expr::BlockExprClass: | |||
15677 | case Expr::NoStmtClass: | |||
15678 | case Expr::OpaqueValueExprClass: | |||
15679 | case Expr::PackExpansionExprClass: | |||
15680 | case Expr::SubstNonTypeTemplateParmPackExprClass: | |||
15681 | case Expr::FunctionParmPackExprClass: | |||
15682 | case Expr::AsTypeExprClass: | |||
15683 | case Expr::ObjCIndirectCopyRestoreExprClass: | |||
15684 | case Expr::MaterializeTemporaryExprClass: | |||
15685 | case Expr::PseudoObjectExprClass: | |||
15686 | case Expr::AtomicExprClass: | |||
15687 | case Expr::LambdaExprClass: | |||
15688 | case Expr::CXXFoldExprClass: | |||
15689 | case Expr::CoawaitExprClass: | |||
15690 | case Expr::DependentCoawaitExprClass: | |||
15691 | case Expr::CoyieldExprClass: | |||
15692 | case Expr::SYCLUniqueStableNameExprClass: | |||
15693 | case Expr::CXXParenListInitExprClass: | |||
15694 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15695 | ||||
15696 | case Expr::InitListExprClass: { | |||
15697 | // C++03 [dcl.init]p13: If T is a scalar type, then a declaration of the | |||
15698 | // form "T x = { a };" is equivalent to "T x = a;". | |||
15699 | // Unless we're initializing a reference, T is a scalar as it is known to be | |||
15700 | // of integral or enumeration type. | |||
15701 | if (E->isPRValue()) | |||
15702 | if (cast<InitListExpr>(E)->getNumInits() == 1) | |||
15703 | return CheckICE(cast<InitListExpr>(E)->getInit(0), Ctx); | |||
15704 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15705 | } | |||
15706 | ||||
15707 | case Expr::SizeOfPackExprClass: | |||
15708 | case Expr::GNUNullExprClass: | |||
15709 | case Expr::SourceLocExprClass: | |||
15710 | return NoDiag(); | |||
15711 | ||||
15712 | case Expr::SubstNonTypeTemplateParmExprClass: | |||
15713 | return | |||
15714 | CheckICE(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement(), Ctx); | |||
15715 | ||||
15716 | case Expr::ConstantExprClass: | |||
15717 | return CheckICE(cast<ConstantExpr>(E)->getSubExpr(), Ctx); | |||
15718 | ||||
15719 | case Expr::ParenExprClass: | |||
15720 | return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx); | |||
15721 | case Expr::GenericSelectionExprClass: | |||
15722 | return CheckICE(cast<GenericSelectionExpr>(E)->getResultExpr(), Ctx); | |||
15723 | case Expr::IntegerLiteralClass: | |||
15724 | case Expr::FixedPointLiteralClass: | |||
15725 | case Expr::CharacterLiteralClass: | |||
15726 | case Expr::ObjCBoolLiteralExprClass: | |||
15727 | case Expr::CXXBoolLiteralExprClass: | |||
15728 | case Expr::CXXScalarValueInitExprClass: | |||
15729 | case Expr::TypeTraitExprClass: | |||
15730 | case Expr::ConceptSpecializationExprClass: | |||
15731 | case Expr::RequiresExprClass: | |||
15732 | case Expr::ArrayTypeTraitExprClass: | |||
15733 | case Expr::ExpressionTraitExprClass: | |||
15734 | case Expr::CXXNoexceptExprClass: | |||
15735 | return NoDiag(); | |||
15736 | case Expr::CallExprClass: | |||
15737 | case Expr::CXXOperatorCallExprClass: { | |||
15738 | // C99 6.6/3 allows function calls within unevaluated subexpressions of | |||
15739 | // constant expressions, but they can never be ICEs because an ICE cannot | |||
15740 | // contain an operand of (pointer to) function type. | |||
15741 | const CallExpr *CE = cast<CallExpr>(E); | |||
15742 | if (CE->getBuiltinCallee()) | |||
15743 | return CheckEvalInICE(E, Ctx); | |||
15744 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15745 | } | |||
15746 | case Expr::CXXRewrittenBinaryOperatorClass: | |||
15747 | return CheckICE(cast<CXXRewrittenBinaryOperator>(E)->getSemanticForm(), | |||
15748 | Ctx); | |||
15749 | case Expr::DeclRefExprClass: { | |||
15750 | const NamedDecl *D = cast<DeclRefExpr>(E)->getDecl(); | |||
15751 | if (isa<EnumConstantDecl>(D)) | |||
15752 | return NoDiag(); | |||
15753 | ||||
15754 | // C++ and OpenCL (FIXME: spec reference?) allow reading const-qualified | |||
15755 | // integer variables in constant expressions: | |||
15756 | // | |||
15757 | // C++ 7.1.5.1p2 | |||
15758 | // A variable of non-volatile const-qualified integral or enumeration | |||
15759 | // type initialized by an ICE can be used in ICEs. | |||
15760 | // | |||
15761 | // We sometimes use CheckICE to check the C++98 rules in C++11 mode. In | |||
15762 | // that mode, use of reference variables should not be allowed. | |||
15763 | const VarDecl *VD = dyn_cast<VarDecl>(D); | |||
15764 | if (VD && VD->isUsableInConstantExpressions(Ctx) && | |||
15765 | !VD->getType()->isReferenceType()) | |||
15766 | return NoDiag(); | |||
15767 | ||||
15768 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15769 | } | |||
15770 | case Expr::UnaryOperatorClass: { | |||
15771 | const UnaryOperator *Exp = cast<UnaryOperator>(E); | |||
15772 | switch (Exp->getOpcode()) { | |||
15773 | case UO_PostInc: | |||
15774 | case UO_PostDec: | |||
15775 | case UO_PreInc: | |||
15776 | case UO_PreDec: | |||
15777 | case UO_AddrOf: | |||
15778 | case UO_Deref: | |||
15779 | case UO_Coawait: | |||
15780 | // C99 6.6/3 allows increment and decrement within unevaluated | |||
15781 | // subexpressions of constant expressions, but they can never be ICEs | |||
15782 | // because an ICE cannot contain an lvalue operand. | |||
15783 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15784 | case UO_Extension: | |||
15785 | case UO_LNot: | |||
15786 | case UO_Plus: | |||
15787 | case UO_Minus: | |||
15788 | case UO_Not: | |||
15789 | case UO_Real: | |||
15790 | case UO_Imag: | |||
15791 | return CheckICE(Exp->getSubExpr(), Ctx); | |||
15792 | } | |||
15793 | llvm_unreachable("invalid unary operator class")::llvm::llvm_unreachable_internal("invalid unary operator class" , "clang/lib/AST/ExprConstant.cpp", 15793); | |||
15794 | } | |||
15795 | case Expr::OffsetOfExprClass: { | |||
15796 | // Note that per C99, offsetof must be an ICE. And AFAIK, using | |||
15797 | // EvaluateAsRValue matches the proposed gcc behavior for cases like | |||
15798 | // "offsetof(struct s{int x[4];}, x[1.0])". This doesn't affect | |||
15799 | // compliance: we should warn earlier for offsetof expressions with | |||
15800 | // array subscripts that aren't ICEs, and if the array subscripts | |||
15801 | // are ICEs, the value of the offsetof must be an integer constant. | |||
15802 | return CheckEvalInICE(E, Ctx); | |||
15803 | } | |||
15804 | case Expr::UnaryExprOrTypeTraitExprClass: { | |||
15805 | const UnaryExprOrTypeTraitExpr *Exp = cast<UnaryExprOrTypeTraitExpr>(E); | |||
15806 | if ((Exp->getKind() == UETT_SizeOf) && | |||
15807 | Exp->getTypeOfArgument()->isVariableArrayType()) | |||
15808 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15809 | return NoDiag(); | |||
15810 | } | |||
15811 | case Expr::BinaryOperatorClass: { | |||
15812 | const BinaryOperator *Exp = cast<BinaryOperator>(E); | |||
15813 | switch (Exp->getOpcode()) { | |||
15814 | case BO_PtrMemD: | |||
15815 | case BO_PtrMemI: | |||
15816 | case BO_Assign: | |||
15817 | case BO_MulAssign: | |||
15818 | case BO_DivAssign: | |||
15819 | case BO_RemAssign: | |||
15820 | case BO_AddAssign: | |||
15821 | case BO_SubAssign: | |||
15822 | case BO_ShlAssign: | |||
15823 | case BO_ShrAssign: | |||
15824 | case BO_AndAssign: | |||
15825 | case BO_XorAssign: | |||
15826 | case BO_OrAssign: | |||
15827 | // C99 6.6/3 allows assignments within unevaluated subexpressions of | |||
15828 | // constant expressions, but they can never be ICEs because an ICE cannot | |||
15829 | // contain an lvalue operand. | |||
15830 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15831 | ||||
15832 | case BO_Mul: | |||
15833 | case BO_Div: | |||
15834 | case BO_Rem: | |||
15835 | case BO_Add: | |||
15836 | case BO_Sub: | |||
15837 | case BO_Shl: | |||
15838 | case BO_Shr: | |||
15839 | case BO_LT: | |||
15840 | case BO_GT: | |||
15841 | case BO_LE: | |||
15842 | case BO_GE: | |||
15843 | case BO_EQ: | |||
15844 | case BO_NE: | |||
15845 | case BO_And: | |||
15846 | case BO_Xor: | |||
15847 | case BO_Or: | |||
15848 | case BO_Comma: | |||
15849 | case BO_Cmp: { | |||
15850 | ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); | |||
15851 | ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); | |||
15852 | if (Exp->getOpcode() == BO_Div || | |||
15853 | Exp->getOpcode() == BO_Rem) { | |||
15854 | // EvaluateAsRValue gives an error for undefined Div/Rem, so make sure | |||
15855 | // we don't evaluate one. | |||
15856 | if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICE) { | |||
15857 | llvm::APSInt REval = Exp->getRHS()->EvaluateKnownConstInt(Ctx); | |||
15858 | if (REval == 0) | |||
15859 | return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc()); | |||
15860 | if (REval.isSigned() && REval.isAllOnes()) { | |||
15861 | llvm::APSInt LEval = Exp->getLHS()->EvaluateKnownConstInt(Ctx); | |||
15862 | if (LEval.isMinSignedValue()) | |||
15863 | return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc()); | |||
15864 | } | |||
15865 | } | |||
15866 | } | |||
15867 | if (Exp->getOpcode() == BO_Comma) { | |||
15868 | if (Ctx.getLangOpts().C99) { | |||
15869 | // C99 6.6p3 introduces a strange edge case: comma can be in an ICE | |||
15870 | // if it isn't evaluated. | |||
15871 | if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICE) | |||
15872 | return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc()); | |||
15873 | } else { | |||
15874 | // In both C89 and C++, commas in ICEs are illegal. | |||
15875 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15876 | } | |||
15877 | } | |||
15878 | return Worst(LHSResult, RHSResult); | |||
15879 | } | |||
15880 | case BO_LAnd: | |||
15881 | case BO_LOr: { | |||
15882 | ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); | |||
15883 | ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); | |||
15884 | if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICEIfUnevaluated) { | |||
15885 | // Rare case where the RHS has a comma "side-effect"; we need | |||
15886 | // to actually check the condition to see whether the side | |||
15887 | // with the comma is evaluated. | |||
15888 | if ((Exp->getOpcode() == BO_LAnd) != | |||
15889 | (Exp->getLHS()->EvaluateKnownConstInt(Ctx) == 0)) | |||
15890 | return RHSResult; | |||
15891 | return NoDiag(); | |||
15892 | } | |||
15893 | ||||
15894 | return Worst(LHSResult, RHSResult); | |||
15895 | } | |||
15896 | } | |||
15897 | llvm_unreachable("invalid binary operator kind")::llvm::llvm_unreachable_internal("invalid binary operator kind" , "clang/lib/AST/ExprConstant.cpp", 15897); | |||
15898 | } | |||
15899 | case Expr::ImplicitCastExprClass: | |||
15900 | case Expr::CStyleCastExprClass: | |||
15901 | case Expr::CXXFunctionalCastExprClass: | |||
15902 | case Expr::CXXStaticCastExprClass: | |||
15903 | case Expr::CXXReinterpretCastExprClass: | |||
15904 | case Expr::CXXConstCastExprClass: | |||
15905 | case Expr::ObjCBridgedCastExprClass: { | |||
15906 | const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr(); | |||
15907 | if (isa<ExplicitCastExpr>(E)) { | |||
15908 | if (const FloatingLiteral *FL | |||
15909 | = dyn_cast<FloatingLiteral>(SubExpr->IgnoreParenImpCasts())) { | |||
15910 | unsigned DestWidth = Ctx.getIntWidth(E->getType()); | |||
15911 | bool DestSigned = E->getType()->isSignedIntegerOrEnumerationType(); | |||
15912 | APSInt IgnoredVal(DestWidth, !DestSigned); | |||
15913 | bool Ignored; | |||
15914 | // If the value does not fit in the destination type, the behavior is | |||
15915 | // undefined, so we are not required to treat it as a constant | |||
15916 | // expression. | |||
15917 | if (FL->getValue().convertToInteger(IgnoredVal, | |||
15918 | llvm::APFloat::rmTowardZero, | |||
15919 | &Ignored) & APFloat::opInvalidOp) | |||
15920 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15921 | return NoDiag(); | |||
15922 | } | |||
15923 | } | |||
15924 | switch (cast<CastExpr>(E)->getCastKind()) { | |||
15925 | case CK_LValueToRValue: | |||
15926 | case CK_AtomicToNonAtomic: | |||
15927 | case CK_NonAtomicToAtomic: | |||
15928 | case CK_NoOp: | |||
15929 | case CK_IntegralToBoolean: | |||
15930 | case CK_IntegralCast: | |||
15931 | return CheckICE(SubExpr, Ctx); | |||
15932 | default: | |||
15933 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15934 | } | |||
15935 | } | |||
15936 | case Expr::BinaryConditionalOperatorClass: { | |||
15937 | const BinaryConditionalOperator *Exp = cast<BinaryConditionalOperator>(E); | |||
15938 | ICEDiag CommonResult = CheckICE(Exp->getCommon(), Ctx); | |||
15939 | if (CommonResult.Kind == IK_NotICE) return CommonResult; | |||
15940 | ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx); | |||
15941 | if (FalseResult.Kind == IK_NotICE) return FalseResult; | |||
15942 | if (CommonResult.Kind == IK_ICEIfUnevaluated) return CommonResult; | |||
15943 | if (FalseResult.Kind == IK_ICEIfUnevaluated && | |||
15944 | Exp->getCommon()->EvaluateKnownConstInt(Ctx) != 0) return NoDiag(); | |||
15945 | return FalseResult; | |||
15946 | } | |||
15947 | case Expr::ConditionalOperatorClass: { | |||
15948 | const ConditionalOperator *Exp = cast<ConditionalOperator>(E); | |||
15949 | // If the condition (ignoring parens) is a __builtin_constant_p call, | |||
15950 | // then only the true side is actually considered in an integer constant | |||
15951 | // expression, and it is fully evaluated. This is an important GNU | |||
15952 | // extension. See GCC PR38377 for discussion. | |||
15953 | if (const CallExpr *CallCE | |||
15954 | = dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts())) | |||
15955 | if (CallCE->getBuiltinCallee() == Builtin::BI__builtin_constant_p) | |||
15956 | return CheckEvalInICE(E, Ctx); | |||
15957 | ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx); | |||
15958 | if (CondResult.Kind == IK_NotICE) | |||
15959 | return CondResult; | |||
15960 | ||||
15961 | ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx); | |||
15962 | ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx); | |||
15963 | ||||
15964 | if (TrueResult.Kind == IK_NotICE) | |||
15965 | return TrueResult; | |||
15966 | if (FalseResult.Kind == IK_NotICE) | |||
15967 | return FalseResult; | |||
15968 | if (CondResult.Kind == IK_ICEIfUnevaluated) | |||
15969 | return CondResult; | |||
15970 | if (TrueResult.Kind == IK_ICE && FalseResult.Kind == IK_ICE) | |||
15971 | return NoDiag(); | |||
15972 | // Rare case where the diagnostics depend on which side is evaluated | |||
15973 | // Note that if we get here, CondResult is 0, and at least one of | |||
15974 | // TrueResult and FalseResult is non-zero. | |||
15975 | if (Exp->getCond()->EvaluateKnownConstInt(Ctx) == 0) | |||
15976 | return FalseResult; | |||
15977 | return TrueResult; | |||
15978 | } | |||
15979 | case Expr::CXXDefaultArgExprClass: | |||
15980 | return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx); | |||
15981 | case Expr::CXXDefaultInitExprClass: | |||
15982 | return CheckICE(cast<CXXDefaultInitExpr>(E)->getExpr(), Ctx); | |||
15983 | case Expr::ChooseExprClass: { | |||
15984 | return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(), Ctx); | |||
15985 | } | |||
15986 | case Expr::BuiltinBitCastExprClass: { | |||
15987 | if (!checkBitCastConstexprEligibility(nullptr, Ctx, cast<CastExpr>(E))) | |||
15988 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
15989 | return CheckICE(cast<CastExpr>(E)->getSubExpr(), Ctx); | |||
15990 | } | |||
15991 | } | |||
15992 | ||||
15993 | llvm_unreachable("Invalid StmtClass!")::llvm::llvm_unreachable_internal("Invalid StmtClass!", "clang/lib/AST/ExprConstant.cpp" , 15993); | |||
15994 | } | |||
15995 | ||||
15996 | /// Evaluate an expression as a C++11 integral constant expression. | |||
15997 | static bool EvaluateCPlusPlus11IntegralConstantExpr(const ASTContext &Ctx, | |||
15998 | const Expr *E, | |||
15999 | llvm::APSInt *Value, | |||
16000 | SourceLocation *Loc) { | |||
16001 | if (!E->getType()->isIntegralOrUnscopedEnumerationType()) { | |||
16002 | if (Loc) *Loc = E->getExprLoc(); | |||
16003 | return false; | |||
16004 | } | |||
16005 | ||||
16006 | APValue Result; | |||
16007 | if (!E->isCXX11ConstantExpr(Ctx, &Result, Loc)) | |||
16008 | return false; | |||
16009 | ||||
16010 | if (!Result.isInt()) { | |||
16011 | if (Loc) *Loc = E->getExprLoc(); | |||
16012 | return false; | |||
16013 | } | |||
16014 | ||||
16015 | if (Value) *Value = Result.getInt(); | |||
16016 | return true; | |||
16017 | } | |||
16018 | ||||
16019 | bool Expr::isIntegerConstantExpr(const ASTContext &Ctx, | |||
16020 | SourceLocation *Loc) const { | |||
16021 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 16022, __extension__ __PRETTY_FUNCTION__ )) | |||
16022 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 16022, __extension__ __PRETTY_FUNCTION__ )); | |||
16023 | ||||
16024 | ExprTimeTraceScope TimeScope(this, Ctx, "isIntegerConstantExpr"); | |||
16025 | ||||
16026 | if (Ctx.getLangOpts().CPlusPlus11) | |||
16027 | return EvaluateCPlusPlus11IntegralConstantExpr(Ctx, this, nullptr, Loc); | |||
16028 | ||||
16029 | ICEDiag D = CheckICE(this, Ctx); | |||
16030 | if (D.Kind != IK_ICE) { | |||
16031 | if (Loc) *Loc = D.Loc; | |||
16032 | return false; | |||
16033 | } | |||
16034 | return true; | |||
16035 | } | |||
16036 | ||||
16037 | std::optional<llvm::APSInt> | |||
16038 | Expr::getIntegerConstantExpr(const ASTContext &Ctx, SourceLocation *Loc, | |||
16039 | bool isEvaluated) const { | |||
16040 | if (isValueDependent()) { | |||
16041 | // Expression evaluator can't succeed on a dependent expression. | |||
16042 | return std::nullopt; | |||
16043 | } | |||
16044 | ||||
16045 | APSInt Value; | |||
16046 | ||||
16047 | if (Ctx.getLangOpts().CPlusPlus11) { | |||
16048 | if (EvaluateCPlusPlus11IntegralConstantExpr(Ctx, this, &Value, Loc)) | |||
16049 | return Value; | |||
16050 | return std::nullopt; | |||
16051 | } | |||
16052 | ||||
16053 | if (!isIntegerConstantExpr(Ctx, Loc)) | |||
16054 | return std::nullopt; | |||
16055 | ||||
16056 | // The only possible side-effects here are due to UB discovered in the | |||
16057 | // evaluation (for instance, INT_MAX + 1). In such a case, we are still | |||
16058 | // required to treat the expression as an ICE, so we produce the folded | |||
16059 | // value. | |||
16060 | EvalResult ExprResult; | |||
16061 | Expr::EvalStatus Status; | |||
16062 | EvalInfo Info(Ctx, Status, EvalInfo::EM_IgnoreSideEffects); | |||
16063 | Info.InConstantContext = true; | |||
16064 | ||||
16065 | if (!::EvaluateAsInt(this, ExprResult, Ctx, SE_AllowSideEffects, Info)) | |||
16066 | llvm_unreachable("ICE cannot be evaluated!")::llvm::llvm_unreachable_internal("ICE cannot be evaluated!", "clang/lib/AST/ExprConstant.cpp", 16066); | |||
16067 | ||||
16068 | return ExprResult.Val.getInt(); | |||
16069 | } | |||
16070 | ||||
16071 | bool Expr::isCXX98IntegralConstantExpr(const ASTContext &Ctx) const { | |||
16072 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 16073, __extension__ __PRETTY_FUNCTION__ )) | |||
16073 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 16073, __extension__ __PRETTY_FUNCTION__ )); | |||
16074 | ||||
16075 | return CheckICE(this, Ctx).Kind == IK_ICE; | |||
16076 | } | |||
16077 | ||||
16078 | bool Expr::isCXX11ConstantExpr(const ASTContext &Ctx, APValue *Result, | |||
16079 | SourceLocation *Loc) const { | |||
16080 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 16081, __extension__ __PRETTY_FUNCTION__ )) | |||
16081 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 16081, __extension__ __PRETTY_FUNCTION__ )); | |||
16082 | ||||
16083 | // We support this checking in C++98 mode in order to diagnose compatibility | |||
16084 | // issues. | |||
16085 | assert(Ctx.getLangOpts().CPlusPlus)(static_cast <bool> (Ctx.getLangOpts().CPlusPlus) ? void (0) : __assert_fail ("Ctx.getLangOpts().CPlusPlus", "clang/lib/AST/ExprConstant.cpp" , 16085, __extension__ __PRETTY_FUNCTION__)); | |||
16086 | ||||
16087 | // Build evaluation settings. | |||
16088 | Expr::EvalStatus Status; | |||
16089 | SmallVector<PartialDiagnosticAt, 8> Diags; | |||
16090 | Status.Diag = &Diags; | |||
16091 | EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpression); | |||
16092 | ||||
16093 | APValue Scratch; | |||
16094 | bool IsConstExpr = | |||
16095 | ::EvaluateAsRValue(Info, this, Result ? *Result : Scratch) && | |||
16096 | // FIXME: We don't produce a diagnostic for this, but the callers that | |||
16097 | // call us on arbitrary full-expressions should generally not care. | |||
16098 | Info.discardCleanups() && !Status.HasSideEffects; | |||
16099 | ||||
16100 | if (!Diags.empty()) { | |||
16101 | IsConstExpr = false; | |||
16102 | if (Loc) *Loc = Diags[0].first; | |||
16103 | } else if (!IsConstExpr) { | |||
16104 | // FIXME: This shouldn't happen. | |||
16105 | if (Loc) *Loc = getExprLoc(); | |||
16106 | } | |||
16107 | ||||
16108 | return IsConstExpr; | |||
16109 | } | |||
16110 | ||||
16111 | bool Expr::EvaluateWithSubstitution(APValue &Value, ASTContext &Ctx, | |||
16112 | const FunctionDecl *Callee, | |||
16113 | ArrayRef<const Expr*> Args, | |||
16114 | const Expr *This) const { | |||
16115 | assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 16116, __extension__ __PRETTY_FUNCTION__ )) | |||
16116 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 16116, __extension__ __PRETTY_FUNCTION__ )); | |||
16117 | ||||
16118 | llvm::TimeTraceScope TimeScope("EvaluateWithSubstitution", [&] { | |||
16119 | std::string Name; | |||
16120 | llvm::raw_string_ostream OS(Name); | |||
16121 | Callee->getNameForDiagnostic(OS, Ctx.getPrintingPolicy(), | |||
16122 | /*Qualified=*/true); | |||
16123 | return Name; | |||
16124 | }); | |||
16125 | ||||
16126 | Expr::EvalStatus Status; | |||
16127 | EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpressionUnevaluated); | |||
16128 | Info.InConstantContext = true; | |||
16129 | ||||
16130 | LValue ThisVal; | |||
16131 | const LValue *ThisPtr = nullptr; | |||
16132 | if (This) { | |||
16133 | #ifndef NDEBUG | |||
16134 | auto *MD = dyn_cast<CXXMethodDecl>(Callee); | |||
16135 | assert(MD && "Don't provide `this` for non-methods.")(static_cast <bool> (MD && "Don't provide `this` for non-methods." ) ? void (0) : __assert_fail ("MD && \"Don't provide `this` for non-methods.\"" , "clang/lib/AST/ExprConstant.cpp", 16135, __extension__ __PRETTY_FUNCTION__ )); | |||
16136 | assert(!MD->isStatic() && "Don't provide `this` for static methods.")(static_cast <bool> (!MD->isStatic() && "Don't provide `this` for static methods." ) ? void (0) : __assert_fail ("!MD->isStatic() && \"Don't provide `this` for static methods.\"" , "clang/lib/AST/ExprConstant.cpp", 16136, __extension__ __PRETTY_FUNCTION__ )); | |||
16137 | #endif | |||
16138 | if (!This->isValueDependent() && | |||
16139 | EvaluateObjectArgument(Info, This, ThisVal) && | |||
16140 | !Info.EvalStatus.HasSideEffects) | |||
16141 | ThisPtr = &ThisVal; | |||
16142 | ||||
16143 | // Ignore any side-effects from a failed evaluation. This is safe because | |||
16144 | // they can't interfere with any other argument evaluation. | |||
16145 | Info.EvalStatus.HasSideEffects = false; | |||
16146 | } | |||
16147 | ||||
16148 | CallRef Call = Info.CurrentCall->createCall(Callee); | |||
16149 | for (ArrayRef<const Expr*>::iterator I = Args.begin(), E = Args.end(); | |||
16150 | I != E; ++I) { | |||
16151 | unsigned Idx = I - Args.begin(); | |||
16152 | if (Idx >= Callee->getNumParams()) | |||
16153 | break; | |||
16154 | const ParmVarDecl *PVD = Callee->getParamDecl(Idx); | |||
16155 | if ((*I)->isValueDependent() || | |||
16156 | !EvaluateCallArg(PVD, *I, Call, Info) || | |||
16157 | Info.EvalStatus.HasSideEffects) { | |||
16158 | // If evaluation fails, throw away the argument entirely. | |||
16159 | if (APValue *Slot = Info.getParamSlot(Call, PVD)) | |||
16160 | *Slot = APValue(); | |||
16161 | } | |||
16162 | ||||
16163 | // Ignore any side-effects from a failed evaluation. This is safe because | |||
16164 | // they can't interfere with any other argument evaluation. | |||
16165 | Info.EvalStatus.HasSideEffects = false; | |||
16166 | } | |||
16167 | ||||
16168 | // Parameter cleanups happen in the caller and are not part of this | |||
16169 | // evaluation. | |||
16170 | Info.discardCleanups(); | |||
16171 | Info.EvalStatus.HasSideEffects = false; | |||
16172 | ||||
16173 | // Build fake call to Callee. | |||
16174 | CallStackFrame Frame(Info, Callee->getLocation(), Callee, ThisPtr, Call); | |||
16175 | // FIXME: Missing ExprWithCleanups in enable_if conditions? | |||
16176 | FullExpressionRAII Scope(Info); | |||
16177 | return Evaluate(Value, Info, this) && Scope.destroy() && | |||
16178 | !Info.EvalStatus.HasSideEffects; | |||
16179 | } | |||
16180 | ||||
16181 | bool Expr::isPotentialConstantExpr(const FunctionDecl *FD, | |||
16182 | SmallVectorImpl< | |||
16183 | PartialDiagnosticAt> &Diags) { | |||
16184 | // FIXME: It would be useful to check constexpr function templates, but at the | |||
16185 | // moment the constant expression evaluator cannot cope with the non-rigorous | |||
16186 | // ASTs which we build for dependent expressions. | |||
16187 | if (FD->isDependentContext()) | |||
16188 | return true; | |||
16189 | ||||
16190 | llvm::TimeTraceScope TimeScope("isPotentialConstantExpr", [&] { | |||
16191 | std::string Name; | |||
16192 | llvm::raw_string_ostream OS(Name); | |||
16193 | FD->getNameForDiagnostic(OS, FD->getASTContext().getPrintingPolicy(), | |||
16194 | /*Qualified=*/true); | |||
16195 | return Name; | |||
16196 | }); | |||
16197 | ||||
16198 | Expr::EvalStatus Status; | |||
16199 | Status.Diag = &Diags; | |||
16200 | ||||
16201 | EvalInfo Info(FD->getASTContext(), Status, EvalInfo::EM_ConstantExpression); | |||
16202 | Info.InConstantContext = true; | |||
16203 | Info.CheckingPotentialConstantExpression = true; | |||
16204 | ||||
16205 | // The constexpr VM attempts to compile all methods to bytecode here. | |||
16206 | if (Info.EnableNewConstInterp) { | |||
16207 | Info.Ctx.getInterpContext().isPotentialConstantExpr(Info, FD); | |||
16208 | return Diags.empty(); | |||
16209 | } | |||
16210 | ||||
16211 | const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD); | |||
16212 | const CXXRecordDecl *RD = MD ? MD->getParent()->getCanonicalDecl() : nullptr; | |||
16213 | ||||
16214 | // Fabricate an arbitrary expression on the stack and pretend that it | |||
16215 | // is a temporary being used as the 'this' pointer. | |||
16216 | LValue This; | |||
16217 | ImplicitValueInitExpr VIE(RD ? Info.Ctx.getRecordType(RD) : Info.Ctx.IntTy); | |||
16218 | This.set({&VIE, Info.CurrentCall->Index}); | |||
16219 | ||||
16220 | ArrayRef<const Expr*> Args; | |||
16221 | ||||
16222 | APValue Scratch; | |||
16223 | if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) { | |||
16224 | // Evaluate the call as a constant initializer, to allow the construction | |||
16225 | // of objects of non-literal types. | |||
16226 | Info.setEvaluatingDecl(This.getLValueBase(), Scratch); | |||
16227 | HandleConstructorCall(&VIE, This, Args, CD, Info, Scratch); | |||
16228 | } else { | |||
16229 | SourceLocation Loc = FD->getLocation(); | |||
16230 | HandleFunctionCall(Loc, FD, (MD && MD->isInstance()) ? &This : nullptr, | |||
16231 | Args, CallRef(), FD->getBody(), Info, Scratch, nullptr); | |||
16232 | } | |||
16233 | ||||
16234 | return Diags.empty(); | |||
16235 | } | |||
16236 | ||||
16237 | bool Expr::isPotentialConstantExprUnevaluated(Expr *E, | |||
16238 | const FunctionDecl *FD, | |||
16239 | SmallVectorImpl< | |||
16240 | PartialDiagnosticAt> &Diags) { | |||
16241 | assert(!E->isValueDependent() &&(static_cast <bool> (!E->isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!E->isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 16242, __extension__ __PRETTY_FUNCTION__ )) | |||
16242 | "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!E->isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? void (0) : __assert_fail ("!E->isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "clang/lib/AST/ExprConstant.cpp", 16242, __extension__ __PRETTY_FUNCTION__ )); | |||
16243 | ||||
16244 | Expr::EvalStatus Status; | |||
16245 | Status.Diag = &Diags; | |||
16246 | ||||
16247 | EvalInfo Info(FD->getASTContext(), Status, | |||
16248 | EvalInfo::EM_ConstantExpressionUnevaluated); | |||
16249 | Info.InConstantContext = true; | |||
16250 | Info.CheckingPotentialConstantExpression = true; | |||
16251 | ||||
16252 | // Fabricate a call stack frame to give the arguments a plausible cover story. | |||
16253 | CallStackFrame Frame(Info, SourceLocation(), FD, /*This*/ nullptr, CallRef()); | |||
16254 | ||||
16255 | APValue ResultScratch; | |||
16256 | Evaluate(ResultScratch, Info, E); | |||
16257 | return Diags.empty(); | |||
16258 | } | |||
16259 | ||||
16260 | bool Expr::tryEvaluateObjectSize(uint64_t &Result, ASTContext &Ctx, | |||
16261 | unsigned Type) const { | |||
16262 | if (!getType()->isPointerType()) | |||
16263 | return false; | |||
16264 | ||||
16265 | Expr::EvalStatus Status; | |||
16266 | EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantFold); | |||
16267 | return tryEvaluateBuiltinObjectSize(this, Type, Info, Result); | |||
16268 | } | |||
16269 | ||||
16270 | static bool EvaluateBuiltinStrLen(const Expr *E, uint64_t &Result, | |||
16271 | EvalInfo &Info) { | |||
16272 | if (!E->getType()->hasPointerRepresentation() || !E->isPRValue()) | |||
16273 | return false; | |||
16274 | ||||
16275 | LValue String; | |||
16276 | ||||
16277 | if (!EvaluatePointer(E, String, Info)) | |||
16278 | return false; | |||
16279 | ||||
16280 | QualType CharTy = E->getType()->getPointeeType(); | |||
16281 | ||||
16282 | // Fast path: if it's a string literal, search the string value. | |||
16283 | if (const StringLiteral *S = dyn_cast_or_null<StringLiteral>( | |||
16284 | String.getLValueBase().dyn_cast<const Expr *>())) { | |||
16285 | StringRef Str = S->getBytes(); | |||
16286 | int64_t Off = String.Offset.getQuantity(); | |||
16287 | if (Off >= 0 && (uint64_t)Off <= (uint64_t)Str.size() && | |||
16288 | S->getCharByteWidth() == 1 && | |||
16289 | // FIXME: Add fast-path for wchar_t too. | |||
16290 | Info.Ctx.hasSameUnqualifiedType(CharTy, Info.Ctx.CharTy)) { | |||
16291 | Str = Str.substr(Off); | |||
16292 | ||||
16293 | StringRef::size_type Pos = Str.find(0); | |||
16294 | if (Pos != StringRef::npos) | |||
16295 | Str = Str.substr(0, Pos); | |||
16296 | ||||
16297 | Result = Str.size(); | |||
16298 | return true; | |||
16299 | } | |||
16300 | ||||
16301 | // Fall through to slow path. | |||
16302 | } | |||
16303 | ||||
16304 | // Slow path: scan the bytes of the string looking for the terminating 0. | |||
16305 | for (uint64_t Strlen = 0; /**/; ++Strlen) { | |||
16306 | APValue Char; | |||
16307 | if (!handleLValueToRValueConversion(Info, E, CharTy, String, Char) || | |||
16308 | !Char.isInt()) | |||
16309 | return false; | |||
16310 | if (!Char.getInt()) { | |||
16311 | Result = Strlen; | |||
16312 | return true; | |||
16313 | } | |||
16314 | if (!HandleLValueArrayAdjustment(Info, E, String, CharTy, 1)) | |||
16315 | return false; | |||
16316 | } | |||
16317 | } | |||
16318 | ||||
16319 | bool Expr::tryEvaluateStrLen(uint64_t &Result, ASTContext &Ctx) const { | |||
16320 | Expr::EvalStatus Status; | |||
16321 | EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantFold); | |||
16322 | return EvaluateBuiltinStrLen(this, Result, Info); | |||
16323 | } |