File: | tools/clang/lib/AST/ExprConstant.cpp |
Warning: | line 12443, column 9 Called C++ object pointer is null |
Press '?' to see keyboard shortcuts
Keyboard shortcuts:
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 <cstring> | |||
36 | #include <functional> | |||
37 | #include "Interp/Context.h" | |||
38 | #include "Interp/Frame.h" | |||
39 | #include "Interp/State.h" | |||
40 | #include "clang/AST/APValue.h" | |||
41 | #include "clang/AST/ASTContext.h" | |||
42 | #include "clang/AST/ASTDiagnostic.h" | |||
43 | #include "clang/AST/ASTLambda.h" | |||
44 | #include "clang/AST/CXXInheritance.h" | |||
45 | #include "clang/AST/CharUnits.h" | |||
46 | #include "clang/AST/CurrentSourceLocExprScope.h" | |||
47 | #include "clang/AST/Expr.h" | |||
48 | #include "clang/AST/OSLog.h" | |||
49 | #include "clang/AST/OptionalDiagnostic.h" | |||
50 | #include "clang/AST/RecordLayout.h" | |||
51 | #include "clang/AST/StmtVisitor.h" | |||
52 | #include "clang/AST/TypeLoc.h" | |||
53 | #include "clang/Basic/Builtins.h" | |||
54 | #include "clang/Basic/FixedPoint.h" | |||
55 | #include "clang/Basic/TargetInfo.h" | |||
56 | #include "llvm/ADT/Optional.h" | |||
57 | #include "llvm/ADT/SmallBitVector.h" | |||
58 | #include "llvm/Support/SaveAndRestore.h" | |||
59 | #include "llvm/Support/raw_ostream.h" | |||
60 | ||||
61 | #define DEBUG_TYPE"exprconstant" "exprconstant" | |||
62 | ||||
63 | using namespace clang; | |||
64 | using llvm::APInt; | |||
65 | using llvm::APSInt; | |||
66 | using llvm::APFloat; | |||
67 | using llvm::Optional; | |||
68 | ||||
69 | namespace { | |||
70 | struct LValue; | |||
71 | class CallStackFrame; | |||
72 | class EvalInfo; | |||
73 | ||||
74 | using SourceLocExprScopeGuard = | |||
75 | CurrentSourceLocExprScope::SourceLocExprScopeGuard; | |||
76 | ||||
77 | static QualType getType(APValue::LValueBase B) { | |||
78 | if (!B) return QualType(); | |||
79 | if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) { | |||
80 | // FIXME: It's unclear where we're supposed to take the type from, and | |||
81 | // this actually matters for arrays of unknown bound. Eg: | |||
82 | // | |||
83 | // extern int arr[]; void f() { extern int arr[3]; }; | |||
84 | // constexpr int *p = &arr[1]; // valid? | |||
85 | // | |||
86 | // For now, we take the array bound from the most recent declaration. | |||
87 | for (auto *Redecl = cast<ValueDecl>(D->getMostRecentDecl()); Redecl; | |||
88 | Redecl = cast_or_null<ValueDecl>(Redecl->getPreviousDecl())) { | |||
89 | QualType T = Redecl->getType(); | |||
90 | if (!T->isIncompleteArrayType()) | |||
91 | return T; | |||
92 | } | |||
93 | return D->getType(); | |||
94 | } | |||
95 | ||||
96 | if (B.is<TypeInfoLValue>()) | |||
97 | return B.getTypeInfoType(); | |||
98 | ||||
99 | if (B.is<DynamicAllocLValue>()) | |||
100 | return B.getDynamicAllocType(); | |||
101 | ||||
102 | const Expr *Base = B.get<const Expr*>(); | |||
103 | ||||
104 | // For a materialized temporary, the type of the temporary we materialized | |||
105 | // may not be the type of the expression. | |||
106 | if (const MaterializeTemporaryExpr *MTE = | |||
107 | dyn_cast<MaterializeTemporaryExpr>(Base)) { | |||
108 | SmallVector<const Expr *, 2> CommaLHSs; | |||
109 | SmallVector<SubobjectAdjustment, 2> Adjustments; | |||
110 | const Expr *Temp = MTE->GetTemporaryExpr(); | |||
111 | const Expr *Inner = Temp->skipRValueSubobjectAdjustments(CommaLHSs, | |||
112 | Adjustments); | |||
113 | // Keep any cv-qualifiers from the reference if we generated a temporary | |||
114 | // for it directly. Otherwise use the type after adjustment. | |||
115 | if (!Adjustments.empty()) | |||
116 | return Inner->getType(); | |||
117 | } | |||
118 | ||||
119 | return Base->getType(); | |||
120 | } | |||
121 | ||||
122 | /// Get an LValue path entry, which is known to not be an array index, as a | |||
123 | /// field declaration. | |||
124 | static const FieldDecl *getAsField(APValue::LValuePathEntry E) { | |||
125 | return dyn_cast_or_null<FieldDecl>(E.getAsBaseOrMember().getPointer()); | |||
126 | } | |||
127 | /// Get an LValue path entry, which is known to not be an array index, as a | |||
128 | /// base class declaration. | |||
129 | static const CXXRecordDecl *getAsBaseClass(APValue::LValuePathEntry E) { | |||
130 | return dyn_cast_or_null<CXXRecordDecl>(E.getAsBaseOrMember().getPointer()); | |||
131 | } | |||
132 | /// Determine whether this LValue path entry for a base class names a virtual | |||
133 | /// base class. | |||
134 | static bool isVirtualBaseClass(APValue::LValuePathEntry E) { | |||
135 | return E.getAsBaseOrMember().getInt(); | |||
136 | } | |||
137 | ||||
138 | /// Given an expression, determine the type used to store the result of | |||
139 | /// evaluating that expression. | |||
140 | static QualType getStorageType(ASTContext &Ctx, Expr *E) { | |||
141 | if (E->isRValue()) | |||
142 | return E->getType(); | |||
143 | return Ctx.getLValueReferenceType(E->getType()); | |||
144 | } | |||
145 | ||||
146 | /// Given a CallExpr, try to get the alloc_size attribute. May return null. | |||
147 | static const AllocSizeAttr *getAllocSizeAttr(const CallExpr *CE) { | |||
148 | const FunctionDecl *Callee = CE->getDirectCallee(); | |||
149 | return Callee ? Callee->getAttr<AllocSizeAttr>() : nullptr; | |||
150 | } | |||
151 | ||||
152 | /// Attempts to unwrap a CallExpr (with an alloc_size attribute) from an Expr. | |||
153 | /// This will look through a single cast. | |||
154 | /// | |||
155 | /// Returns null if we couldn't unwrap a function with alloc_size. | |||
156 | static const CallExpr *tryUnwrapAllocSizeCall(const Expr *E) { | |||
157 | if (!E->getType()->isPointerType()) | |||
158 | return nullptr; | |||
159 | ||||
160 | E = E->IgnoreParens(); | |||
161 | // If we're doing a variable assignment from e.g. malloc(N), there will | |||
162 | // probably be a cast of some kind. In exotic cases, we might also see a | |||
163 | // top-level ExprWithCleanups. Ignore them either way. | |||
164 | if (const auto *FE = dyn_cast<FullExpr>(E)) | |||
165 | E = FE->getSubExpr()->IgnoreParens(); | |||
166 | ||||
167 | if (const auto *Cast = dyn_cast<CastExpr>(E)) | |||
168 | E = Cast->getSubExpr()->IgnoreParens(); | |||
169 | ||||
170 | if (const auto *CE = dyn_cast<CallExpr>(E)) | |||
171 | return getAllocSizeAttr(CE) ? CE : nullptr; | |||
172 | return nullptr; | |||
173 | } | |||
174 | ||||
175 | /// Determines whether or not the given Base contains a call to a function | |||
176 | /// with the alloc_size attribute. | |||
177 | static bool isBaseAnAllocSizeCall(APValue::LValueBase Base) { | |||
178 | const auto *E = Base.dyn_cast<const Expr *>(); | |||
179 | return E && E->getType()->isPointerType() && tryUnwrapAllocSizeCall(E); | |||
180 | } | |||
181 | ||||
182 | /// The bound to claim that an array of unknown bound has. | |||
183 | /// The value in MostDerivedArraySize is undefined in this case. So, set it | |||
184 | /// to an arbitrary value that's likely to loudly break things if it's used. | |||
185 | static const uint64_t AssumedSizeForUnsizedArray = | |||
186 | std::numeric_limits<uint64_t>::max() / 2; | |||
187 | ||||
188 | /// Determines if an LValue with the given LValueBase will have an unsized | |||
189 | /// array in its designator. | |||
190 | /// Find the path length and type of the most-derived subobject in the given | |||
191 | /// path, and find the size of the containing array, if any. | |||
192 | static unsigned | |||
193 | findMostDerivedSubobject(ASTContext &Ctx, APValue::LValueBase Base, | |||
194 | ArrayRef<APValue::LValuePathEntry> Path, | |||
195 | uint64_t &ArraySize, QualType &Type, bool &IsArray, | |||
196 | bool &FirstEntryIsUnsizedArray) { | |||
197 | // This only accepts LValueBases from APValues, and APValues don't support | |||
198 | // arrays that lack size info. | |||
199 | assert(!isBaseAnAllocSizeCall(Base) &&((!isBaseAnAllocSizeCall(Base) && "Unsized arrays shouldn't appear here" ) ? static_cast<void> (0) : __assert_fail ("!isBaseAnAllocSizeCall(Base) && \"Unsized arrays shouldn't appear here\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 200, __PRETTY_FUNCTION__)) | |||
200 | "Unsized arrays shouldn't appear here")((!isBaseAnAllocSizeCall(Base) && "Unsized arrays shouldn't appear here" ) ? static_cast<void> (0) : __assert_fail ("!isBaseAnAllocSizeCall(Base) && \"Unsized arrays shouldn't appear here\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 200, __PRETTY_FUNCTION__)); | |||
201 | unsigned MostDerivedLength = 0; | |||
202 | Type = getType(Base); | |||
203 | ||||
204 | for (unsigned I = 0, N = Path.size(); I != N; ++I) { | |||
205 | if (Type->isArrayType()) { | |||
206 | const ArrayType *AT = Ctx.getAsArrayType(Type); | |||
207 | Type = AT->getElementType(); | |||
208 | MostDerivedLength = I + 1; | |||
209 | IsArray = true; | |||
210 | ||||
211 | if (auto *CAT = dyn_cast<ConstantArrayType>(AT)) { | |||
212 | ArraySize = CAT->getSize().getZExtValue(); | |||
213 | } else { | |||
214 | assert(I == 0 && "unexpected unsized array designator")((I == 0 && "unexpected unsized array designator") ? static_cast <void> (0) : __assert_fail ("I == 0 && \"unexpected unsized array designator\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 214, __PRETTY_FUNCTION__)); | |||
215 | FirstEntryIsUnsizedArray = true; | |||
216 | ArraySize = AssumedSizeForUnsizedArray; | |||
217 | } | |||
218 | } else if (Type->isAnyComplexType()) { | |||
219 | const ComplexType *CT = Type->castAs<ComplexType>(); | |||
220 | Type = CT->getElementType(); | |||
221 | ArraySize = 2; | |||
222 | MostDerivedLength = I + 1; | |||
223 | IsArray = true; | |||
224 | } else if (const FieldDecl *FD = getAsField(Path[I])) { | |||
225 | Type = FD->getType(); | |||
226 | ArraySize = 0; | |||
227 | MostDerivedLength = I + 1; | |||
228 | IsArray = false; | |||
229 | } else { | |||
230 | // Path[I] describes a base class. | |||
231 | ArraySize = 0; | |||
232 | IsArray = false; | |||
233 | } | |||
234 | } | |||
235 | return MostDerivedLength; | |||
236 | } | |||
237 | ||||
238 | /// A path from a glvalue to a subobject of that glvalue. | |||
239 | struct SubobjectDesignator { | |||
240 | /// True if the subobject was named in a manner not supported by C++11. Such | |||
241 | /// lvalues can still be folded, but they are not core constant expressions | |||
242 | /// and we cannot perform lvalue-to-rvalue conversions on them. | |||
243 | unsigned Invalid : 1; | |||
244 | ||||
245 | /// Is this a pointer one past the end of an object? | |||
246 | unsigned IsOnePastTheEnd : 1; | |||
247 | ||||
248 | /// Indicator of whether the first entry is an unsized array. | |||
249 | unsigned FirstEntryIsAnUnsizedArray : 1; | |||
250 | ||||
251 | /// Indicator of whether the most-derived object is an array element. | |||
252 | unsigned MostDerivedIsArrayElement : 1; | |||
253 | ||||
254 | /// The length of the path to the most-derived object of which this is a | |||
255 | /// subobject. | |||
256 | unsigned MostDerivedPathLength : 28; | |||
257 | ||||
258 | /// The size of the array of which the most-derived object is an element. | |||
259 | /// This will always be 0 if the most-derived object is not an array | |||
260 | /// element. 0 is not an indicator of whether or not the most-derived object | |||
261 | /// is an array, however, because 0-length arrays are allowed. | |||
262 | /// | |||
263 | /// If the current array is an unsized array, the value of this is | |||
264 | /// undefined. | |||
265 | uint64_t MostDerivedArraySize; | |||
266 | ||||
267 | /// The type of the most derived object referred to by this address. | |||
268 | QualType MostDerivedType; | |||
269 | ||||
270 | typedef APValue::LValuePathEntry PathEntry; | |||
271 | ||||
272 | /// The entries on the path from the glvalue to the designated subobject. | |||
273 | SmallVector<PathEntry, 8> Entries; | |||
274 | ||||
275 | SubobjectDesignator() : Invalid(true) {} | |||
276 | ||||
277 | explicit SubobjectDesignator(QualType T) | |||
278 | : Invalid(false), IsOnePastTheEnd(false), | |||
279 | FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false), | |||
280 | MostDerivedPathLength(0), MostDerivedArraySize(0), | |||
281 | MostDerivedType(T) {} | |||
282 | ||||
283 | SubobjectDesignator(ASTContext &Ctx, const APValue &V) | |||
284 | : Invalid(!V.isLValue() || !V.hasLValuePath()), IsOnePastTheEnd(false), | |||
285 | FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false), | |||
286 | MostDerivedPathLength(0), MostDerivedArraySize(0) { | |||
287 | assert(V.isLValue() && "Non-LValue used to make an LValue designator?")((V.isLValue() && "Non-LValue used to make an LValue designator?" ) ? static_cast<void> (0) : __assert_fail ("V.isLValue() && \"Non-LValue used to make an LValue designator?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 287, __PRETTY_FUNCTION__)); | |||
288 | if (!Invalid) { | |||
289 | IsOnePastTheEnd = V.isLValueOnePastTheEnd(); | |||
290 | ArrayRef<PathEntry> VEntries = V.getLValuePath(); | |||
291 | Entries.insert(Entries.end(), VEntries.begin(), VEntries.end()); | |||
292 | if (V.getLValueBase()) { | |||
293 | bool IsArray = false; | |||
294 | bool FirstIsUnsizedArray = false; | |||
295 | MostDerivedPathLength = findMostDerivedSubobject( | |||
296 | Ctx, V.getLValueBase(), V.getLValuePath(), MostDerivedArraySize, | |||
297 | MostDerivedType, IsArray, FirstIsUnsizedArray); | |||
298 | MostDerivedIsArrayElement = IsArray; | |||
299 | FirstEntryIsAnUnsizedArray = FirstIsUnsizedArray; | |||
300 | } | |||
301 | } | |||
302 | } | |||
303 | ||||
304 | void truncate(ASTContext &Ctx, APValue::LValueBase Base, | |||
305 | unsigned NewLength) { | |||
306 | if (Invalid) | |||
307 | return; | |||
308 | ||||
309 | assert(Base && "cannot truncate path for null pointer")((Base && "cannot truncate path for null pointer") ? static_cast <void> (0) : __assert_fail ("Base && \"cannot truncate path for null pointer\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 309, __PRETTY_FUNCTION__)); | |||
310 | assert(NewLength <= Entries.size() && "not a truncation")((NewLength <= Entries.size() && "not a truncation" ) ? static_cast<void> (0) : __assert_fail ("NewLength <= Entries.size() && \"not a truncation\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 310, __PRETTY_FUNCTION__)); | |||
311 | ||||
312 | if (NewLength == Entries.size()) | |||
313 | return; | |||
314 | Entries.resize(NewLength); | |||
315 | ||||
316 | bool IsArray = false; | |||
317 | bool FirstIsUnsizedArray = false; | |||
318 | MostDerivedPathLength = findMostDerivedSubobject( | |||
319 | Ctx, Base, Entries, MostDerivedArraySize, MostDerivedType, IsArray, | |||
320 | FirstIsUnsizedArray); | |||
321 | MostDerivedIsArrayElement = IsArray; | |||
322 | FirstEntryIsAnUnsizedArray = FirstIsUnsizedArray; | |||
323 | } | |||
324 | ||||
325 | void setInvalid() { | |||
326 | Invalid = true; | |||
327 | Entries.clear(); | |||
328 | } | |||
329 | ||||
330 | /// Determine whether the most derived subobject is an array without a | |||
331 | /// known bound. | |||
332 | bool isMostDerivedAnUnsizedArray() const { | |||
333 | assert(!Invalid && "Calling this makes no sense on invalid designators")((!Invalid && "Calling this makes no sense on invalid designators" ) ? static_cast<void> (0) : __assert_fail ("!Invalid && \"Calling this makes no sense on invalid designators\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 333, __PRETTY_FUNCTION__)); | |||
334 | return Entries.size() == 1 && FirstEntryIsAnUnsizedArray; | |||
335 | } | |||
336 | ||||
337 | /// Determine what the most derived array's size is. Results in an assertion | |||
338 | /// failure if the most derived array lacks a size. | |||
339 | uint64_t getMostDerivedArraySize() const { | |||
340 | assert(!isMostDerivedAnUnsizedArray() && "Unsized array has no size")((!isMostDerivedAnUnsizedArray() && "Unsized array has no size" ) ? static_cast<void> (0) : __assert_fail ("!isMostDerivedAnUnsizedArray() && \"Unsized array has no size\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 340, __PRETTY_FUNCTION__)); | |||
341 | return MostDerivedArraySize; | |||
342 | } | |||
343 | ||||
344 | /// Determine whether this is a one-past-the-end pointer. | |||
345 | bool isOnePastTheEnd() const { | |||
346 | assert(!Invalid)((!Invalid) ? static_cast<void> (0) : __assert_fail ("!Invalid" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 346, __PRETTY_FUNCTION__)); | |||
347 | if (IsOnePastTheEnd) | |||
348 | return true; | |||
349 | if (!isMostDerivedAnUnsizedArray() && MostDerivedIsArrayElement && | |||
350 | Entries[MostDerivedPathLength - 1].getAsArrayIndex() == | |||
351 | MostDerivedArraySize) | |||
352 | return true; | |||
353 | return false; | |||
354 | } | |||
355 | ||||
356 | /// Get the range of valid index adjustments in the form | |||
357 | /// {maximum value that can be subtracted from this pointer, | |||
358 | /// maximum value that can be added to this pointer} | |||
359 | std::pair<uint64_t, uint64_t> validIndexAdjustments() { | |||
360 | if (Invalid || isMostDerivedAnUnsizedArray()) | |||
361 | return {0, 0}; | |||
362 | ||||
363 | // [expr.add]p4: For the purposes of these operators, a pointer to a | |||
364 | // nonarray object behaves the same as a pointer to the first element of | |||
365 | // an array of length one with the type of the object as its element type. | |||
366 | bool IsArray = MostDerivedPathLength == Entries.size() && | |||
367 | MostDerivedIsArrayElement; | |||
368 | uint64_t ArrayIndex = IsArray ? Entries.back().getAsArrayIndex() | |||
369 | : (uint64_t)IsOnePastTheEnd; | |||
370 | uint64_t ArraySize = | |||
371 | IsArray ? getMostDerivedArraySize() : (uint64_t)1; | |||
372 | return {ArrayIndex, ArraySize - ArrayIndex}; | |||
373 | } | |||
374 | ||||
375 | /// Check that this refers to a valid subobject. | |||
376 | bool isValidSubobject() const { | |||
377 | if (Invalid) | |||
378 | return false; | |||
379 | return !isOnePastTheEnd(); | |||
380 | } | |||
381 | /// Check that this refers to a valid subobject, and if not, produce a | |||
382 | /// relevant diagnostic and set the designator as invalid. | |||
383 | bool checkSubobject(EvalInfo &Info, const Expr *E, CheckSubobjectKind CSK); | |||
384 | ||||
385 | /// Get the type of the designated object. | |||
386 | QualType getType(ASTContext &Ctx) const { | |||
387 | assert(!Invalid && "invalid designator has no subobject type")((!Invalid && "invalid designator has no subobject type" ) ? static_cast<void> (0) : __assert_fail ("!Invalid && \"invalid designator has no subobject type\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 387, __PRETTY_FUNCTION__)); | |||
388 | return MostDerivedPathLength == Entries.size() | |||
389 | ? MostDerivedType | |||
390 | : Ctx.getRecordType(getAsBaseClass(Entries.back())); | |||
391 | } | |||
392 | ||||
393 | /// Update this designator to refer to the first element within this array. | |||
394 | void addArrayUnchecked(const ConstantArrayType *CAT) { | |||
395 | Entries.push_back(PathEntry::ArrayIndex(0)); | |||
396 | ||||
397 | // This is a most-derived object. | |||
398 | MostDerivedType = CAT->getElementType(); | |||
399 | MostDerivedIsArrayElement = true; | |||
400 | MostDerivedArraySize = CAT->getSize().getZExtValue(); | |||
401 | MostDerivedPathLength = Entries.size(); | |||
402 | } | |||
403 | /// Update this designator to refer to the first element within the array of | |||
404 | /// elements of type T. This is an array of unknown size. | |||
405 | void addUnsizedArrayUnchecked(QualType ElemTy) { | |||
406 | Entries.push_back(PathEntry::ArrayIndex(0)); | |||
407 | ||||
408 | MostDerivedType = ElemTy; | |||
409 | MostDerivedIsArrayElement = true; | |||
410 | // The value in MostDerivedArraySize is undefined in this case. So, set it | |||
411 | // to an arbitrary value that's likely to loudly break things if it's | |||
412 | // used. | |||
413 | MostDerivedArraySize = AssumedSizeForUnsizedArray; | |||
414 | MostDerivedPathLength = Entries.size(); | |||
415 | } | |||
416 | /// Update this designator to refer to the given base or member of this | |||
417 | /// object. | |||
418 | void addDeclUnchecked(const Decl *D, bool Virtual = false) { | |||
419 | Entries.push_back(APValue::BaseOrMemberType(D, Virtual)); | |||
420 | ||||
421 | // If this isn't a base class, it's a new most-derived object. | |||
422 | if (const FieldDecl *FD = dyn_cast<FieldDecl>(D)) { | |||
423 | MostDerivedType = FD->getType(); | |||
424 | MostDerivedIsArrayElement = false; | |||
425 | MostDerivedArraySize = 0; | |||
426 | MostDerivedPathLength = Entries.size(); | |||
427 | } | |||
428 | } | |||
429 | /// Update this designator to refer to the given complex component. | |||
430 | void addComplexUnchecked(QualType EltTy, bool Imag) { | |||
431 | Entries.push_back(PathEntry::ArrayIndex(Imag)); | |||
432 | ||||
433 | // This is technically a most-derived object, though in practice this | |||
434 | // is unlikely to matter. | |||
435 | MostDerivedType = EltTy; | |||
436 | MostDerivedIsArrayElement = true; | |||
437 | MostDerivedArraySize = 2; | |||
438 | MostDerivedPathLength = Entries.size(); | |||
439 | } | |||
440 | void diagnoseUnsizedArrayPointerArithmetic(EvalInfo &Info, const Expr *E); | |||
441 | void diagnosePointerArithmetic(EvalInfo &Info, const Expr *E, | |||
442 | const APSInt &N); | |||
443 | /// Add N to the address of this subobject. | |||
444 | void adjustIndex(EvalInfo &Info, const Expr *E, APSInt N) { | |||
445 | if (Invalid || !N) return; | |||
446 | uint64_t TruncatedN = N.extOrTrunc(64).getZExtValue(); | |||
447 | if (isMostDerivedAnUnsizedArray()) { | |||
448 | diagnoseUnsizedArrayPointerArithmetic(Info, E); | |||
449 | // Can't verify -- trust that the user is doing the right thing (or if | |||
450 | // not, trust that the caller will catch the bad behavior). | |||
451 | // FIXME: Should we reject if this overflows, at least? | |||
452 | Entries.back() = PathEntry::ArrayIndex( | |||
453 | Entries.back().getAsArrayIndex() + TruncatedN); | |||
454 | return; | |||
455 | } | |||
456 | ||||
457 | // [expr.add]p4: For the purposes of these operators, a pointer to a | |||
458 | // nonarray object behaves the same as a pointer to the first element of | |||
459 | // an array of length one with the type of the object as its element type. | |||
460 | bool IsArray = MostDerivedPathLength == Entries.size() && | |||
461 | MostDerivedIsArrayElement; | |||
462 | uint64_t ArrayIndex = IsArray ? Entries.back().getAsArrayIndex() | |||
463 | : (uint64_t)IsOnePastTheEnd; | |||
464 | uint64_t ArraySize = | |||
465 | IsArray ? getMostDerivedArraySize() : (uint64_t)1; | |||
466 | ||||
467 | if (N < -(int64_t)ArrayIndex || N > ArraySize - ArrayIndex) { | |||
468 | // Calculate the actual index in a wide enough type, so we can include | |||
469 | // it in the note. | |||
470 | N = N.extend(std::max<unsigned>(N.getBitWidth() + 1, 65)); | |||
471 | (llvm::APInt&)N += ArrayIndex; | |||
472 | assert(N.ugt(ArraySize) && "bounds check failed for in-bounds index")((N.ugt(ArraySize) && "bounds check failed for in-bounds index" ) ? static_cast<void> (0) : __assert_fail ("N.ugt(ArraySize) && \"bounds check failed for in-bounds index\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 472, __PRETTY_FUNCTION__)); | |||
473 | diagnosePointerArithmetic(Info, E, N); | |||
474 | setInvalid(); | |||
475 | return; | |||
476 | } | |||
477 | ||||
478 | ArrayIndex += TruncatedN; | |||
479 | assert(ArrayIndex <= ArraySize &&((ArrayIndex <= ArraySize && "bounds check succeeded for out-of-bounds index" ) ? static_cast<void> (0) : __assert_fail ("ArrayIndex <= ArraySize && \"bounds check succeeded for out-of-bounds index\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 480, __PRETTY_FUNCTION__)) | |||
480 | "bounds check succeeded for out-of-bounds index")((ArrayIndex <= ArraySize && "bounds check succeeded for out-of-bounds index" ) ? static_cast<void> (0) : __assert_fail ("ArrayIndex <= ArraySize && \"bounds check succeeded for out-of-bounds index\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 480, __PRETTY_FUNCTION__)); | |||
481 | ||||
482 | if (IsArray) | |||
483 | Entries.back() = PathEntry::ArrayIndex(ArrayIndex); | |||
484 | else | |||
485 | IsOnePastTheEnd = (ArrayIndex != 0); | |||
486 | } | |||
487 | }; | |||
488 | ||||
489 | /// A stack frame in the constexpr call stack. | |||
490 | class CallStackFrame : public interp::Frame { | |||
491 | public: | |||
492 | EvalInfo &Info; | |||
493 | ||||
494 | /// Parent - The caller of this stack frame. | |||
495 | CallStackFrame *Caller; | |||
496 | ||||
497 | /// Callee - The function which was called. | |||
498 | const FunctionDecl *Callee; | |||
499 | ||||
500 | /// This - The binding for the this pointer in this call, if any. | |||
501 | const LValue *This; | |||
502 | ||||
503 | /// Arguments - Parameter bindings for this function call, indexed by | |||
504 | /// parameters' function scope indices. | |||
505 | APValue *Arguments; | |||
506 | ||||
507 | /// Source location information about the default argument or default | |||
508 | /// initializer expression we're evaluating, if any. | |||
509 | CurrentSourceLocExprScope CurSourceLocExprScope; | |||
510 | ||||
511 | // Note that we intentionally use std::map here so that references to | |||
512 | // values are stable. | |||
513 | typedef std::pair<const void *, unsigned> MapKeyTy; | |||
514 | typedef std::map<MapKeyTy, APValue> MapTy; | |||
515 | /// Temporaries - Temporary lvalues materialized within this stack frame. | |||
516 | MapTy Temporaries; | |||
517 | ||||
518 | /// CallLoc - The location of the call expression for this call. | |||
519 | SourceLocation CallLoc; | |||
520 | ||||
521 | /// Index - The call index of this call. | |||
522 | unsigned Index; | |||
523 | ||||
524 | /// The stack of integers for tracking version numbers for temporaries. | |||
525 | SmallVector<unsigned, 2> TempVersionStack = {1}; | |||
526 | unsigned CurTempVersion = TempVersionStack.back(); | |||
527 | ||||
528 | unsigned getTempVersion() const { return TempVersionStack.back(); } | |||
529 | ||||
530 | void pushTempVersion() { | |||
531 | TempVersionStack.push_back(++CurTempVersion); | |||
532 | } | |||
533 | ||||
534 | void popTempVersion() { | |||
535 | TempVersionStack.pop_back(); | |||
536 | } | |||
537 | ||||
538 | // FIXME: Adding this to every 'CallStackFrame' may have a nontrivial impact | |||
539 | // on the overall stack usage of deeply-recursing constexpr evaluations. | |||
540 | // (We should cache this map rather than recomputing it repeatedly.) | |||
541 | // But let's try this and see how it goes; we can look into caching the map | |||
542 | // as a later change. | |||
543 | ||||
544 | /// LambdaCaptureFields - Mapping from captured variables/this to | |||
545 | /// corresponding data members in the closure class. | |||
546 | llvm::DenseMap<const VarDecl *, FieldDecl *> LambdaCaptureFields; | |||
547 | FieldDecl *LambdaThisCaptureField; | |||
548 | ||||
549 | CallStackFrame(EvalInfo &Info, SourceLocation CallLoc, | |||
550 | const FunctionDecl *Callee, const LValue *This, | |||
551 | APValue *Arguments); | |||
552 | ~CallStackFrame(); | |||
553 | ||||
554 | // Return the temporary for Key whose version number is Version. | |||
555 | APValue *getTemporary(const void *Key, unsigned Version) { | |||
556 | MapKeyTy KV(Key, Version); | |||
557 | auto LB = Temporaries.lower_bound(KV); | |||
558 | if (LB != Temporaries.end() && LB->first == KV) | |||
559 | return &LB->second; | |||
560 | // Pair (Key,Version) wasn't found in the map. Check that no elements | |||
561 | // in the map have 'Key' as their key. | |||
562 | assert((LB == Temporaries.end() || LB->first.first != Key) &&(((LB == Temporaries.end() || LB->first.first != Key) && (LB == Temporaries.begin() || std::prev(LB)->first.first != Key) && "Element with key 'Key' found in map") ? static_cast <void> (0) : __assert_fail ("(LB == Temporaries.end() || LB->first.first != Key) && (LB == Temporaries.begin() || std::prev(LB)->first.first != Key) && \"Element with key 'Key' found in map\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 564, __PRETTY_FUNCTION__)) | |||
563 | (LB == Temporaries.begin() || std::prev(LB)->first.first != Key) &&(((LB == Temporaries.end() || LB->first.first != Key) && (LB == Temporaries.begin() || std::prev(LB)->first.first != Key) && "Element with key 'Key' found in map") ? static_cast <void> (0) : __assert_fail ("(LB == Temporaries.end() || LB->first.first != Key) && (LB == Temporaries.begin() || std::prev(LB)->first.first != Key) && \"Element with key 'Key' found in map\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 564, __PRETTY_FUNCTION__)) | |||
564 | "Element with key 'Key' found in map")(((LB == Temporaries.end() || LB->first.first != Key) && (LB == Temporaries.begin() || std::prev(LB)->first.first != Key) && "Element with key 'Key' found in map") ? static_cast <void> (0) : __assert_fail ("(LB == Temporaries.end() || LB->first.first != Key) && (LB == Temporaries.begin() || std::prev(LB)->first.first != Key) && \"Element with key 'Key' found in map\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 564, __PRETTY_FUNCTION__)); | |||
565 | return nullptr; | |||
566 | } | |||
567 | ||||
568 | // Return the current temporary for Key in the map. | |||
569 | APValue *getCurrentTemporary(const void *Key) { | |||
570 | auto UB = Temporaries.upper_bound(MapKeyTy(Key, UINT_MAX(2147483647 *2U +1U))); | |||
571 | if (UB != Temporaries.begin() && std::prev(UB)->first.first == Key) | |||
572 | return &std::prev(UB)->second; | |||
573 | return nullptr; | |||
574 | } | |||
575 | ||||
576 | // Return the version number of the current temporary for Key. | |||
577 | unsigned getCurrentTemporaryVersion(const void *Key) const { | |||
578 | auto UB = Temporaries.upper_bound(MapKeyTy(Key, UINT_MAX(2147483647 *2U +1U))); | |||
579 | if (UB != Temporaries.begin() && std::prev(UB)->first.first == Key) | |||
580 | return std::prev(UB)->first.second; | |||
581 | return 0; | |||
582 | } | |||
583 | ||||
584 | /// Allocate storage for an object of type T in this stack frame. | |||
585 | /// Populates LV with a handle to the created object. Key identifies | |||
586 | /// the temporary within the stack frame, and must not be reused without | |||
587 | /// bumping the temporary version number. | |||
588 | template<typename KeyT> | |||
589 | APValue &createTemporary(const KeyT *Key, QualType T, | |||
590 | bool IsLifetimeExtended, LValue &LV); | |||
591 | ||||
592 | void describe(llvm::raw_ostream &OS) override; | |||
593 | ||||
594 | Frame *getCaller() const override { return Caller; } | |||
595 | SourceLocation getCallLocation() const override { return CallLoc; } | |||
596 | const FunctionDecl *getCallee() const override { return Callee; } | |||
597 | }; | |||
598 | ||||
599 | /// Temporarily override 'this'. | |||
600 | class ThisOverrideRAII { | |||
601 | public: | |||
602 | ThisOverrideRAII(CallStackFrame &Frame, const LValue *NewThis, bool Enable) | |||
603 | : Frame(Frame), OldThis(Frame.This) { | |||
604 | if (Enable) | |||
605 | Frame.This = NewThis; | |||
606 | } | |||
607 | ~ThisOverrideRAII() { | |||
608 | Frame.This = OldThis; | |||
609 | } | |||
610 | private: | |||
611 | CallStackFrame &Frame; | |||
612 | const LValue *OldThis; | |||
613 | }; | |||
614 | } | |||
615 | ||||
616 | static bool HandleDestruction(EvalInfo &Info, const Expr *E, | |||
617 | const LValue &This, QualType ThisType); | |||
618 | static bool HandleDestruction(EvalInfo &Info, SourceLocation Loc, | |||
619 | APValue::LValueBase LVBase, APValue &Value, | |||
620 | QualType T); | |||
621 | ||||
622 | namespace { | |||
623 | /// A cleanup, and a flag indicating whether it is lifetime-extended. | |||
624 | class Cleanup { | |||
625 | llvm::PointerIntPair<APValue*, 1, bool> Value; | |||
626 | APValue::LValueBase Base; | |||
627 | QualType T; | |||
628 | ||||
629 | public: | |||
630 | Cleanup(APValue *Val, APValue::LValueBase Base, QualType T, | |||
631 | bool IsLifetimeExtended) | |||
632 | : Value(Val, IsLifetimeExtended), Base(Base), T(T) {} | |||
633 | ||||
634 | bool isLifetimeExtended() const { return Value.getInt(); } | |||
635 | bool endLifetime(EvalInfo &Info, bool RunDestructors) { | |||
636 | if (RunDestructors) { | |||
637 | SourceLocation Loc; | |||
638 | if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>()) | |||
639 | Loc = VD->getLocation(); | |||
640 | else if (const Expr *E = Base.dyn_cast<const Expr*>()) | |||
641 | Loc = E->getExprLoc(); | |||
642 | return HandleDestruction(Info, Loc, Base, *Value.getPointer(), T); | |||
643 | } | |||
644 | *Value.getPointer() = APValue(); | |||
645 | return true; | |||
646 | } | |||
647 | ||||
648 | bool hasSideEffect() { | |||
649 | return T.isDestructedType(); | |||
650 | } | |||
651 | }; | |||
652 | ||||
653 | /// A reference to an object whose construction we are currently evaluating. | |||
654 | struct ObjectUnderConstruction { | |||
655 | APValue::LValueBase Base; | |||
656 | ArrayRef<APValue::LValuePathEntry> Path; | |||
657 | friend bool operator==(const ObjectUnderConstruction &LHS, | |||
658 | const ObjectUnderConstruction &RHS) { | |||
659 | return LHS.Base == RHS.Base && LHS.Path == RHS.Path; | |||
660 | } | |||
661 | friend llvm::hash_code hash_value(const ObjectUnderConstruction &Obj) { | |||
662 | return llvm::hash_combine(Obj.Base, Obj.Path); | |||
663 | } | |||
664 | }; | |||
665 | enum class ConstructionPhase { | |||
666 | None, | |||
667 | Bases, | |||
668 | AfterBases, | |||
669 | Destroying, | |||
670 | DestroyingBases | |||
671 | }; | |||
672 | } | |||
673 | ||||
674 | namespace llvm { | |||
675 | template<> struct DenseMapInfo<ObjectUnderConstruction> { | |||
676 | using Base = DenseMapInfo<APValue::LValueBase>; | |||
677 | static ObjectUnderConstruction getEmptyKey() { | |||
678 | return {Base::getEmptyKey(), {}}; } | |||
679 | static ObjectUnderConstruction getTombstoneKey() { | |||
680 | return {Base::getTombstoneKey(), {}}; | |||
681 | } | |||
682 | static unsigned getHashValue(const ObjectUnderConstruction &Object) { | |||
683 | return hash_value(Object); | |||
684 | } | |||
685 | static bool isEqual(const ObjectUnderConstruction &LHS, | |||
686 | const ObjectUnderConstruction &RHS) { | |||
687 | return LHS == RHS; | |||
688 | } | |||
689 | }; | |||
690 | } | |||
691 | ||||
692 | namespace { | |||
693 | /// EvalInfo - This is a private struct used by the evaluator to capture | |||
694 | /// information about a subexpression as it is folded. It retains information | |||
695 | /// about the AST context, but also maintains information about the folded | |||
696 | /// expression. | |||
697 | /// | |||
698 | /// If an expression could be evaluated, it is still possible it is not a C | |||
699 | /// "integer constant expression" or constant expression. If not, this struct | |||
700 | /// captures information about how and why not. | |||
701 | /// | |||
702 | /// One bit of information passed *into* the request for constant folding | |||
703 | /// indicates whether the subexpression is "evaluated" or not according to C | |||
704 | /// rules. For example, the RHS of (0 && foo()) is not evaluated. We can | |||
705 | /// evaluate the expression regardless of what the RHS is, but C only allows | |||
706 | /// certain things in certain situations. | |||
707 | class EvalInfo : public interp::State { | |||
708 | public: | |||
709 | ASTContext &Ctx; | |||
710 | ||||
711 | /// EvalStatus - Contains information about the evaluation. | |||
712 | Expr::EvalStatus &EvalStatus; | |||
713 | ||||
714 | /// CurrentCall - The top of the constexpr call stack. | |||
715 | CallStackFrame *CurrentCall; | |||
716 | ||||
717 | /// CallStackDepth - The number of calls in the call stack right now. | |||
718 | unsigned CallStackDepth; | |||
719 | ||||
720 | /// NextCallIndex - The next call index to assign. | |||
721 | unsigned NextCallIndex; | |||
722 | ||||
723 | /// StepsLeft - The remaining number of evaluation steps we're permitted | |||
724 | /// to perform. This is essentially a limit for the number of statements | |||
725 | /// we will evaluate. | |||
726 | unsigned StepsLeft; | |||
727 | ||||
728 | /// Force the use of the experimental new constant interpreter, bailing out | |||
729 | /// with an error if a feature is not supported. | |||
730 | bool ForceNewConstInterp; | |||
731 | ||||
732 | /// Enable the experimental new constant interpreter. | |||
733 | bool EnableNewConstInterp; | |||
734 | ||||
735 | /// BottomFrame - The frame in which evaluation started. This must be | |||
736 | /// initialized after CurrentCall and CallStackDepth. | |||
737 | CallStackFrame BottomFrame; | |||
738 | ||||
739 | /// A stack of values whose lifetimes end at the end of some surrounding | |||
740 | /// evaluation frame. | |||
741 | llvm::SmallVector<Cleanup, 16> CleanupStack; | |||
742 | ||||
743 | /// EvaluatingDecl - This is the declaration whose initializer is being | |||
744 | /// evaluated, if any. | |||
745 | APValue::LValueBase EvaluatingDecl; | |||
746 | ||||
747 | enum class EvaluatingDeclKind { | |||
748 | None, | |||
749 | /// We're evaluating the construction of EvaluatingDecl. | |||
750 | Ctor, | |||
751 | /// We're evaluating the destruction of EvaluatingDecl. | |||
752 | Dtor, | |||
753 | }; | |||
754 | EvaluatingDeclKind IsEvaluatingDecl = EvaluatingDeclKind::None; | |||
755 | ||||
756 | /// EvaluatingDeclValue - This is the value being constructed for the | |||
757 | /// declaration whose initializer is being evaluated, if any. | |||
758 | APValue *EvaluatingDeclValue; | |||
759 | ||||
760 | /// Set of objects that are currently being constructed. | |||
761 | llvm::DenseMap<ObjectUnderConstruction, ConstructionPhase> | |||
762 | ObjectsUnderConstruction; | |||
763 | ||||
764 | /// A dynamically-allocated heap object. | |||
765 | struct DynAlloc { | |||
766 | /// The value of this heap-allocated object. | |||
767 | APValue Value; | |||
768 | /// The allocating expression; used for diagnostics. | |||
769 | const Expr *AllocExpr = nullptr; | |||
770 | }; | |||
771 | ||||
772 | struct DynAllocOrder { | |||
773 | bool operator()(DynamicAllocLValue L, DynamicAllocLValue R) const { | |||
774 | return L.getIndex() < R.getIndex(); | |||
775 | } | |||
776 | }; | |||
777 | ||||
778 | /// Current heap allocations, along with the location where each was | |||
779 | /// allocated. We use std::map here because we need stable addresses | |||
780 | /// for the stored APValues. | |||
781 | std::map<DynamicAllocLValue, DynAlloc, DynAllocOrder> HeapAllocs; | |||
782 | ||||
783 | /// The number of heap allocations performed so far in this evaluation. | |||
784 | unsigned NumHeapAllocs = 0; | |||
785 | ||||
786 | struct EvaluatingConstructorRAII { | |||
787 | EvalInfo &EI; | |||
788 | ObjectUnderConstruction Object; | |||
789 | bool DidInsert; | |||
790 | EvaluatingConstructorRAII(EvalInfo &EI, ObjectUnderConstruction Object, | |||
791 | bool HasBases) | |||
792 | : EI(EI), Object(Object) { | |||
793 | DidInsert = | |||
794 | EI.ObjectsUnderConstruction | |||
795 | .insert({Object, HasBases ? ConstructionPhase::Bases | |||
796 | : ConstructionPhase::AfterBases}) | |||
797 | .second; | |||
798 | } | |||
799 | void finishedConstructingBases() { | |||
800 | EI.ObjectsUnderConstruction[Object] = ConstructionPhase::AfterBases; | |||
801 | } | |||
802 | ~EvaluatingConstructorRAII() { | |||
803 | if (DidInsert) EI.ObjectsUnderConstruction.erase(Object); | |||
804 | } | |||
805 | }; | |||
806 | ||||
807 | struct EvaluatingDestructorRAII { | |||
808 | EvalInfo &EI; | |||
809 | ObjectUnderConstruction Object; | |||
810 | bool DidInsert; | |||
811 | EvaluatingDestructorRAII(EvalInfo &EI, ObjectUnderConstruction Object) | |||
812 | : EI(EI), Object(Object) { | |||
813 | DidInsert = EI.ObjectsUnderConstruction | |||
814 | .insert({Object, ConstructionPhase::Destroying}) | |||
815 | .second; | |||
816 | } | |||
817 | void startedDestroyingBases() { | |||
818 | EI.ObjectsUnderConstruction[Object] = | |||
819 | ConstructionPhase::DestroyingBases; | |||
820 | } | |||
821 | ~EvaluatingDestructorRAII() { | |||
822 | if (DidInsert) | |||
823 | EI.ObjectsUnderConstruction.erase(Object); | |||
824 | } | |||
825 | }; | |||
826 | ||||
827 | ConstructionPhase | |||
828 | isEvaluatingCtorDtor(APValue::LValueBase Base, | |||
829 | ArrayRef<APValue::LValuePathEntry> Path) { | |||
830 | return ObjectsUnderConstruction.lookup({Base, Path}); | |||
831 | } | |||
832 | ||||
833 | /// If we're currently speculatively evaluating, the outermost call stack | |||
834 | /// depth at which we can mutate state, otherwise 0. | |||
835 | unsigned SpeculativeEvaluationDepth = 0; | |||
836 | ||||
837 | /// The current array initialization index, if we're performing array | |||
838 | /// initialization. | |||
839 | uint64_t ArrayInitIndex = -1; | |||
840 | ||||
841 | /// HasActiveDiagnostic - Was the previous diagnostic stored? If so, further | |||
842 | /// notes attached to it will also be stored, otherwise they will not be. | |||
843 | bool HasActiveDiagnostic; | |||
844 | ||||
845 | /// Have we emitted a diagnostic explaining why we couldn't constant | |||
846 | /// fold (not just why it's not strictly a constant expression)? | |||
847 | bool HasFoldFailureDiagnostic; | |||
848 | ||||
849 | /// Whether or not we're in a context where the front end requires a | |||
850 | /// constant value. | |||
851 | bool InConstantContext; | |||
852 | ||||
853 | /// Whether we're checking that an expression is a potential constant | |||
854 | /// expression. If so, do not fail on constructs that could become constant | |||
855 | /// later on (such as a use of an undefined global). | |||
856 | bool CheckingPotentialConstantExpression = false; | |||
857 | ||||
858 | /// Whether we're checking for an expression that has undefined behavior. | |||
859 | /// If so, we will produce warnings if we encounter an operation that is | |||
860 | /// always undefined. | |||
861 | bool CheckingForUndefinedBehavior = false; | |||
862 | ||||
863 | enum EvaluationMode { | |||
864 | /// Evaluate as a constant expression. Stop if we find that the expression | |||
865 | /// is not a constant expression. | |||
866 | EM_ConstantExpression, | |||
867 | ||||
868 | /// Evaluate as a constant expression. Stop if we find that the expression | |||
869 | /// is not a constant expression. Some expressions can be retried in the | |||
870 | /// optimizer if we don't constant fold them here, but in an unevaluated | |||
871 | /// context we try to fold them immediately since the optimizer never | |||
872 | /// gets a chance to look at it. | |||
873 | EM_ConstantExpressionUnevaluated, | |||
874 | ||||
875 | /// Fold the expression to a constant. Stop if we hit a side-effect that | |||
876 | /// we can't model. | |||
877 | EM_ConstantFold, | |||
878 | ||||
879 | /// Evaluate in any way we know how. Don't worry about side-effects that | |||
880 | /// can't be modeled. | |||
881 | EM_IgnoreSideEffects, | |||
882 | } EvalMode; | |||
883 | ||||
884 | /// Are we checking whether the expression is a potential constant | |||
885 | /// expression? | |||
886 | bool checkingPotentialConstantExpression() const override { | |||
887 | return CheckingPotentialConstantExpression; | |||
888 | } | |||
889 | ||||
890 | /// Are we checking an expression for overflow? | |||
891 | // FIXME: We should check for any kind of undefined or suspicious behavior | |||
892 | // in such constructs, not just overflow. | |||
893 | bool checkingForUndefinedBehavior() const override { | |||
894 | return CheckingForUndefinedBehavior; | |||
895 | } | |||
896 | ||||
897 | EvalInfo(const ASTContext &C, Expr::EvalStatus &S, EvaluationMode Mode) | |||
898 | : Ctx(const_cast<ASTContext &>(C)), EvalStatus(S), CurrentCall(nullptr), | |||
899 | CallStackDepth(0), NextCallIndex(1), | |||
900 | StepsLeft(getLangOpts().ConstexprStepLimit), | |||
901 | ForceNewConstInterp(getLangOpts().ForceNewConstInterp), | |||
902 | EnableNewConstInterp(ForceNewConstInterp || | |||
903 | getLangOpts().EnableNewConstInterp), | |||
904 | BottomFrame(*this, SourceLocation(), nullptr, nullptr, nullptr), | |||
905 | EvaluatingDecl((const ValueDecl *)nullptr), | |||
906 | EvaluatingDeclValue(nullptr), HasActiveDiagnostic(false), | |||
907 | HasFoldFailureDiagnostic(false), InConstantContext(false), | |||
908 | EvalMode(Mode) {} | |||
909 | ||||
910 | ~EvalInfo() { | |||
911 | discardCleanups(); | |||
912 | } | |||
913 | ||||
914 | void setEvaluatingDecl(APValue::LValueBase Base, APValue &Value, | |||
915 | EvaluatingDeclKind EDK = EvaluatingDeclKind::Ctor) { | |||
916 | EvaluatingDecl = Base; | |||
917 | IsEvaluatingDecl = EDK; | |||
918 | EvaluatingDeclValue = &Value; | |||
919 | } | |||
920 | ||||
921 | bool CheckCallLimit(SourceLocation Loc) { | |||
922 | // Don't perform any constexpr calls (other than the call we're checking) | |||
923 | // when checking a potential constant expression. | |||
924 | if (checkingPotentialConstantExpression() && CallStackDepth > 1) | |||
925 | return false; | |||
926 | if (NextCallIndex == 0) { | |||
927 | // NextCallIndex has wrapped around. | |||
928 | FFDiag(Loc, diag::note_constexpr_call_limit_exceeded); | |||
929 | return false; | |||
930 | } | |||
931 | if (CallStackDepth <= getLangOpts().ConstexprCallDepth) | |||
932 | return true; | |||
933 | FFDiag(Loc, diag::note_constexpr_depth_limit_exceeded) | |||
934 | << getLangOpts().ConstexprCallDepth; | |||
935 | return false; | |||
936 | } | |||
937 | ||||
938 | std::pair<CallStackFrame *, unsigned> | |||
939 | getCallFrameAndDepth(unsigned CallIndex) { | |||
940 | assert(CallIndex && "no call index in getCallFrameAndDepth")((CallIndex && "no call index in getCallFrameAndDepth" ) ? static_cast<void> (0) : __assert_fail ("CallIndex && \"no call index in getCallFrameAndDepth\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 940, __PRETTY_FUNCTION__)); | |||
941 | // We will eventually hit BottomFrame, which has Index 1, so Frame can't | |||
942 | // be null in this loop. | |||
943 | unsigned Depth = CallStackDepth; | |||
944 | CallStackFrame *Frame = CurrentCall; | |||
945 | while (Frame->Index > CallIndex) { | |||
946 | Frame = Frame->Caller; | |||
947 | --Depth; | |||
948 | } | |||
949 | if (Frame->Index == CallIndex) | |||
950 | return {Frame, Depth}; | |||
951 | return {nullptr, 0}; | |||
952 | } | |||
953 | ||||
954 | bool nextStep(const Stmt *S) { | |||
955 | if (!StepsLeft) { | |||
956 | FFDiag(S->getBeginLoc(), diag::note_constexpr_step_limit_exceeded); | |||
957 | return false; | |||
958 | } | |||
959 | --StepsLeft; | |||
960 | return true; | |||
961 | } | |||
962 | ||||
963 | APValue *createHeapAlloc(const Expr *E, QualType T, LValue &LV); | |||
964 | ||||
965 | Optional<DynAlloc*> lookupDynamicAlloc(DynamicAllocLValue DA) { | |||
966 | Optional<DynAlloc*> Result; | |||
967 | auto It = HeapAllocs.find(DA); | |||
968 | if (It != HeapAllocs.end()) | |||
969 | Result = &It->second; | |||
970 | return Result; | |||
971 | } | |||
972 | ||||
973 | void performLifetimeExtension() { | |||
974 | // Disable the cleanups for lifetime-extended temporaries. | |||
975 | CleanupStack.erase( | |||
976 | std::remove_if(CleanupStack.begin(), CleanupStack.end(), | |||
977 | [](Cleanup &C) { return C.isLifetimeExtended(); }), | |||
978 | CleanupStack.end()); | |||
979 | } | |||
980 | ||||
981 | /// Throw away any remaining cleanups at the end of evaluation. If any | |||
982 | /// cleanups would have had a side-effect, note that as an unmodeled | |||
983 | /// side-effect and return false. Otherwise, return true. | |||
984 | bool discardCleanups() { | |||
985 | for (Cleanup &C : CleanupStack) | |||
986 | if (C.hasSideEffect()) | |||
987 | if (!noteSideEffect()) | |||
988 | return false; | |||
989 | return true; | |||
990 | } | |||
991 | ||||
992 | private: | |||
993 | interp::Frame *getCurrentFrame() override { return CurrentCall; } | |||
994 | const interp::Frame *getBottomFrame() const override { return &BottomFrame; } | |||
995 | ||||
996 | bool hasActiveDiagnostic() override { return HasActiveDiagnostic; } | |||
997 | void setActiveDiagnostic(bool Flag) override { HasActiveDiagnostic = Flag; } | |||
998 | ||||
999 | void setFoldFailureDiagnostic(bool Flag) override { | |||
1000 | HasFoldFailureDiagnostic = Flag; | |||
1001 | } | |||
1002 | ||||
1003 | Expr::EvalStatus &getEvalStatus() const override { return EvalStatus; } | |||
1004 | ||||
1005 | ASTContext &getCtx() const override { return Ctx; } | |||
1006 | ||||
1007 | // If we have a prior diagnostic, it will be noting that the expression | |||
1008 | // isn't a constant expression. This diagnostic is more important, | |||
1009 | // unless we require this evaluation to produce a constant expression. | |||
1010 | // | |||
1011 | // FIXME: We might want to show both diagnostics to the user in | |||
1012 | // EM_ConstantFold mode. | |||
1013 | bool hasPriorDiagnostic() override { | |||
1014 | if (!EvalStatus.Diag->empty()) { | |||
1015 | switch (EvalMode) { | |||
1016 | case EM_ConstantFold: | |||
1017 | case EM_IgnoreSideEffects: | |||
1018 | if (!HasFoldFailureDiagnostic) | |||
1019 | break; | |||
1020 | // We've already failed to fold something. Keep that diagnostic. | |||
1021 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
1022 | case EM_ConstantExpression: | |||
1023 | case EM_ConstantExpressionUnevaluated: | |||
1024 | setActiveDiagnostic(false); | |||
1025 | return true; | |||
1026 | } | |||
1027 | } | |||
1028 | return false; | |||
1029 | } | |||
1030 | ||||
1031 | unsigned getCallStackDepth() override { return CallStackDepth; } | |||
1032 | ||||
1033 | public: | |||
1034 | /// Should we continue evaluation after encountering a side-effect that we | |||
1035 | /// couldn't model? | |||
1036 | bool keepEvaluatingAfterSideEffect() { | |||
1037 | switch (EvalMode) { | |||
1038 | case EM_IgnoreSideEffects: | |||
1039 | return true; | |||
1040 | ||||
1041 | case EM_ConstantExpression: | |||
1042 | case EM_ConstantExpressionUnevaluated: | |||
1043 | case EM_ConstantFold: | |||
1044 | // By default, assume any side effect might be valid in some other | |||
1045 | // evaluation of this expression from a different context. | |||
1046 | return checkingPotentialConstantExpression() || | |||
1047 | checkingForUndefinedBehavior(); | |||
1048 | } | |||
1049 | llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1049); | |||
1050 | } | |||
1051 | ||||
1052 | /// Note that we have had a side-effect, and determine whether we should | |||
1053 | /// keep evaluating. | |||
1054 | bool noteSideEffect() { | |||
1055 | EvalStatus.HasSideEffects = true; | |||
1056 | return keepEvaluatingAfterSideEffect(); | |||
1057 | } | |||
1058 | ||||
1059 | /// Should we continue evaluation after encountering undefined behavior? | |||
1060 | bool keepEvaluatingAfterUndefinedBehavior() { | |||
1061 | switch (EvalMode) { | |||
1062 | case EM_IgnoreSideEffects: | |||
1063 | case EM_ConstantFold: | |||
1064 | return true; | |||
1065 | ||||
1066 | case EM_ConstantExpression: | |||
1067 | case EM_ConstantExpressionUnevaluated: | |||
1068 | return checkingForUndefinedBehavior(); | |||
1069 | } | |||
1070 | llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1070); | |||
1071 | } | |||
1072 | ||||
1073 | /// Note that we hit something that was technically undefined behavior, but | |||
1074 | /// that we can evaluate past it (such as signed overflow or floating-point | |||
1075 | /// division by zero.) | |||
1076 | bool noteUndefinedBehavior() override { | |||
1077 | EvalStatus.HasUndefinedBehavior = true; | |||
1078 | return keepEvaluatingAfterUndefinedBehavior(); | |||
1079 | } | |||
1080 | ||||
1081 | /// Should we continue evaluation as much as possible after encountering a | |||
1082 | /// construct which can't be reduced to a value? | |||
1083 | bool keepEvaluatingAfterFailure() const override { | |||
1084 | if (!StepsLeft) | |||
1085 | return false; | |||
1086 | ||||
1087 | switch (EvalMode) { | |||
1088 | case EM_ConstantExpression: | |||
1089 | case EM_ConstantExpressionUnevaluated: | |||
1090 | case EM_ConstantFold: | |||
1091 | case EM_IgnoreSideEffects: | |||
1092 | return checkingPotentialConstantExpression() || | |||
1093 | checkingForUndefinedBehavior(); | |||
1094 | } | |||
1095 | llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1095); | |||
1096 | } | |||
1097 | ||||
1098 | /// Notes that we failed to evaluate an expression that other expressions | |||
1099 | /// directly depend on, and determine if we should keep evaluating. This | |||
1100 | /// should only be called if we actually intend to keep evaluating. | |||
1101 | /// | |||
1102 | /// Call noteSideEffect() instead if we may be able to ignore the value that | |||
1103 | /// we failed to evaluate, e.g. if we failed to evaluate Foo() in: | |||
1104 | /// | |||
1105 | /// (Foo(), 1) // use noteSideEffect | |||
1106 | /// (Foo() || true) // use noteSideEffect | |||
1107 | /// Foo() + 1 // use noteFailure | |||
1108 | LLVM_NODISCARD[[clang::warn_unused_result]] bool noteFailure() { | |||
1109 | // Failure when evaluating some expression often means there is some | |||
1110 | // subexpression whose evaluation was skipped. Therefore, (because we | |||
1111 | // don't track whether we skipped an expression when unwinding after an | |||
1112 | // evaluation failure) every evaluation failure that bubbles up from a | |||
1113 | // subexpression implies that a side-effect has potentially happened. We | |||
1114 | // skip setting the HasSideEffects flag to true until we decide to | |||
1115 | // continue evaluating after that point, which happens here. | |||
1116 | bool KeepGoing = keepEvaluatingAfterFailure(); | |||
1117 | EvalStatus.HasSideEffects |= KeepGoing; | |||
1118 | return KeepGoing; | |||
1119 | } | |||
1120 | ||||
1121 | class ArrayInitLoopIndex { | |||
1122 | EvalInfo &Info; | |||
1123 | uint64_t OuterIndex; | |||
1124 | ||||
1125 | public: | |||
1126 | ArrayInitLoopIndex(EvalInfo &Info) | |||
1127 | : Info(Info), OuterIndex(Info.ArrayInitIndex) { | |||
1128 | Info.ArrayInitIndex = 0; | |||
1129 | } | |||
1130 | ~ArrayInitLoopIndex() { Info.ArrayInitIndex = OuterIndex; } | |||
1131 | ||||
1132 | operator uint64_t&() { return Info.ArrayInitIndex; } | |||
1133 | }; | |||
1134 | }; | |||
1135 | ||||
1136 | /// Object used to treat all foldable expressions as constant expressions. | |||
1137 | struct FoldConstant { | |||
1138 | EvalInfo &Info; | |||
1139 | bool Enabled; | |||
1140 | bool HadNoPriorDiags; | |||
1141 | EvalInfo::EvaluationMode OldMode; | |||
1142 | ||||
1143 | explicit FoldConstant(EvalInfo &Info, bool Enabled) | |||
1144 | : Info(Info), | |||
1145 | Enabled(Enabled), | |||
1146 | HadNoPriorDiags(Info.EvalStatus.Diag && | |||
1147 | Info.EvalStatus.Diag->empty() && | |||
1148 | !Info.EvalStatus.HasSideEffects), | |||
1149 | OldMode(Info.EvalMode) { | |||
1150 | if (Enabled) | |||
1151 | Info.EvalMode = EvalInfo::EM_ConstantFold; | |||
1152 | } | |||
1153 | void keepDiagnostics() { Enabled = false; } | |||
1154 | ~FoldConstant() { | |||
1155 | if (Enabled && HadNoPriorDiags && !Info.EvalStatus.Diag->empty() && | |||
1156 | !Info.EvalStatus.HasSideEffects) | |||
1157 | Info.EvalStatus.Diag->clear(); | |||
1158 | Info.EvalMode = OldMode; | |||
1159 | } | |||
1160 | }; | |||
1161 | ||||
1162 | /// RAII object used to set the current evaluation mode to ignore | |||
1163 | /// side-effects. | |||
1164 | struct IgnoreSideEffectsRAII { | |||
1165 | EvalInfo &Info; | |||
1166 | EvalInfo::EvaluationMode OldMode; | |||
1167 | explicit IgnoreSideEffectsRAII(EvalInfo &Info) | |||
1168 | : Info(Info), OldMode(Info.EvalMode) { | |||
1169 | Info.EvalMode = EvalInfo::EM_IgnoreSideEffects; | |||
1170 | } | |||
1171 | ||||
1172 | ~IgnoreSideEffectsRAII() { Info.EvalMode = OldMode; } | |||
1173 | }; | |||
1174 | ||||
1175 | /// RAII object used to optionally suppress diagnostics and side-effects from | |||
1176 | /// a speculative evaluation. | |||
1177 | class SpeculativeEvaluationRAII { | |||
1178 | EvalInfo *Info = nullptr; | |||
1179 | Expr::EvalStatus OldStatus; | |||
1180 | unsigned OldSpeculativeEvaluationDepth; | |||
1181 | ||||
1182 | void moveFromAndCancel(SpeculativeEvaluationRAII &&Other) { | |||
1183 | Info = Other.Info; | |||
1184 | OldStatus = Other.OldStatus; | |||
1185 | OldSpeculativeEvaluationDepth = Other.OldSpeculativeEvaluationDepth; | |||
1186 | Other.Info = nullptr; | |||
1187 | } | |||
1188 | ||||
1189 | void maybeRestoreState() { | |||
1190 | if (!Info) | |||
1191 | return; | |||
1192 | ||||
1193 | Info->EvalStatus = OldStatus; | |||
1194 | Info->SpeculativeEvaluationDepth = OldSpeculativeEvaluationDepth; | |||
1195 | } | |||
1196 | ||||
1197 | public: | |||
1198 | SpeculativeEvaluationRAII() = default; | |||
1199 | ||||
1200 | SpeculativeEvaluationRAII( | |||
1201 | EvalInfo &Info, SmallVectorImpl<PartialDiagnosticAt> *NewDiag = nullptr) | |||
1202 | : Info(&Info), OldStatus(Info.EvalStatus), | |||
1203 | OldSpeculativeEvaluationDepth(Info.SpeculativeEvaluationDepth) { | |||
1204 | Info.EvalStatus.Diag = NewDiag; | |||
1205 | Info.SpeculativeEvaluationDepth = Info.CallStackDepth + 1; | |||
1206 | } | |||
1207 | ||||
1208 | SpeculativeEvaluationRAII(const SpeculativeEvaluationRAII &Other) = delete; | |||
1209 | SpeculativeEvaluationRAII(SpeculativeEvaluationRAII &&Other) { | |||
1210 | moveFromAndCancel(std::move(Other)); | |||
1211 | } | |||
1212 | ||||
1213 | SpeculativeEvaluationRAII &operator=(SpeculativeEvaluationRAII &&Other) { | |||
1214 | maybeRestoreState(); | |||
1215 | moveFromAndCancel(std::move(Other)); | |||
1216 | return *this; | |||
1217 | } | |||
1218 | ||||
1219 | ~SpeculativeEvaluationRAII() { maybeRestoreState(); } | |||
1220 | }; | |||
1221 | ||||
1222 | /// RAII object wrapping a full-expression or block scope, and handling | |||
1223 | /// the ending of the lifetime of temporaries created within it. | |||
1224 | template<bool IsFullExpression> | |||
1225 | class ScopeRAII { | |||
1226 | EvalInfo &Info; | |||
1227 | unsigned OldStackSize; | |||
1228 | public: | |||
1229 | ScopeRAII(EvalInfo &Info) | |||
1230 | : Info(Info), OldStackSize(Info.CleanupStack.size()) { | |||
1231 | // Push a new temporary version. This is needed to distinguish between | |||
1232 | // temporaries created in different iterations of a loop. | |||
1233 | Info.CurrentCall->pushTempVersion(); | |||
1234 | } | |||
1235 | bool destroy(bool RunDestructors = true) { | |||
1236 | bool OK = cleanup(Info, RunDestructors, OldStackSize); | |||
1237 | OldStackSize = -1U; | |||
1238 | return OK; | |||
1239 | } | |||
1240 | ~ScopeRAII() { | |||
1241 | if (OldStackSize != -1U) | |||
1242 | destroy(false); | |||
1243 | // Body moved to a static method to encourage the compiler to inline away | |||
1244 | // instances of this class. | |||
1245 | Info.CurrentCall->popTempVersion(); | |||
1246 | } | |||
1247 | private: | |||
1248 | static bool cleanup(EvalInfo &Info, bool RunDestructors, | |||
1249 | unsigned OldStackSize) { | |||
1250 | assert(OldStackSize <= Info.CleanupStack.size() &&((OldStackSize <= Info.CleanupStack.size() && "running cleanups out of order?" ) ? static_cast<void> (0) : __assert_fail ("OldStackSize <= Info.CleanupStack.size() && \"running cleanups out of order?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1251, __PRETTY_FUNCTION__)) | |||
1251 | "running cleanups out of order?")((OldStackSize <= Info.CleanupStack.size() && "running cleanups out of order?" ) ? static_cast<void> (0) : __assert_fail ("OldStackSize <= Info.CleanupStack.size() && \"running cleanups out of order?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1251, __PRETTY_FUNCTION__)); | |||
1252 | ||||
1253 | // Run all cleanups for a block scope, and non-lifetime-extended cleanups | |||
1254 | // for a full-expression scope. | |||
1255 | bool Success = true; | |||
1256 | for (unsigned I = Info.CleanupStack.size(); I > OldStackSize; --I) { | |||
1257 | if (!(IsFullExpression && | |||
1258 | Info.CleanupStack[I - 1].isLifetimeExtended())) { | |||
1259 | if (!Info.CleanupStack[I - 1].endLifetime(Info, RunDestructors)) { | |||
1260 | Success = false; | |||
1261 | break; | |||
1262 | } | |||
1263 | } | |||
1264 | } | |||
1265 | ||||
1266 | // Compact lifetime-extended cleanups. | |||
1267 | auto NewEnd = Info.CleanupStack.begin() + OldStackSize; | |||
1268 | if (IsFullExpression) | |||
1269 | NewEnd = | |||
1270 | std::remove_if(NewEnd, Info.CleanupStack.end(), | |||
1271 | [](Cleanup &C) { return !C.isLifetimeExtended(); }); | |||
1272 | Info.CleanupStack.erase(NewEnd, Info.CleanupStack.end()); | |||
1273 | return Success; | |||
1274 | } | |||
1275 | }; | |||
1276 | typedef ScopeRAII<false> BlockScopeRAII; | |||
1277 | typedef ScopeRAII<true> FullExpressionRAII; | |||
1278 | } | |||
1279 | ||||
1280 | bool SubobjectDesignator::checkSubobject(EvalInfo &Info, const Expr *E, | |||
1281 | CheckSubobjectKind CSK) { | |||
1282 | if (Invalid) | |||
1283 | return false; | |||
1284 | if (isOnePastTheEnd()) { | |||
1285 | Info.CCEDiag(E, diag::note_constexpr_past_end_subobject) | |||
1286 | << CSK; | |||
1287 | setInvalid(); | |||
1288 | return false; | |||
1289 | } | |||
1290 | // Note, we do not diagnose if isMostDerivedAnUnsizedArray(), because there | |||
1291 | // must actually be at least one array element; even a VLA cannot have a | |||
1292 | // bound of zero. And if our index is nonzero, we already had a CCEDiag. | |||
1293 | return true; | |||
1294 | } | |||
1295 | ||||
1296 | void SubobjectDesignator::diagnoseUnsizedArrayPointerArithmetic(EvalInfo &Info, | |||
1297 | const Expr *E) { | |||
1298 | Info.CCEDiag(E, diag::note_constexpr_unsized_array_indexed); | |||
1299 | // Do not set the designator as invalid: we can represent this situation, | |||
1300 | // and correct handling of __builtin_object_size requires us to do so. | |||
1301 | } | |||
1302 | ||||
1303 | void SubobjectDesignator::diagnosePointerArithmetic(EvalInfo &Info, | |||
1304 | const Expr *E, | |||
1305 | const APSInt &N) { | |||
1306 | // If we're complaining, we must be able to statically determine the size of | |||
1307 | // the most derived array. | |||
1308 | if (MostDerivedPathLength == Entries.size() && MostDerivedIsArrayElement) | |||
1309 | Info.CCEDiag(E, diag::note_constexpr_array_index) | |||
1310 | << N << /*array*/ 0 | |||
1311 | << static_cast<unsigned>(getMostDerivedArraySize()); | |||
1312 | else | |||
1313 | Info.CCEDiag(E, diag::note_constexpr_array_index) | |||
1314 | << N << /*non-array*/ 1; | |||
1315 | setInvalid(); | |||
1316 | } | |||
1317 | ||||
1318 | CallStackFrame::CallStackFrame(EvalInfo &Info, SourceLocation CallLoc, | |||
1319 | const FunctionDecl *Callee, const LValue *This, | |||
1320 | APValue *Arguments) | |||
1321 | : Info(Info), Caller(Info.CurrentCall), Callee(Callee), This(This), | |||
1322 | Arguments(Arguments), CallLoc(CallLoc), Index(Info.NextCallIndex++) { | |||
1323 | Info.CurrentCall = this; | |||
1324 | ++Info.CallStackDepth; | |||
1325 | } | |||
1326 | ||||
1327 | CallStackFrame::~CallStackFrame() { | |||
1328 | assert(Info.CurrentCall == this && "calls retired out of order")((Info.CurrentCall == this && "calls retired out of order" ) ? static_cast<void> (0) : __assert_fail ("Info.CurrentCall == this && \"calls retired out of order\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1328, __PRETTY_FUNCTION__)); | |||
1329 | --Info.CallStackDepth; | |||
1330 | Info.CurrentCall = Caller; | |||
1331 | } | |||
1332 | ||||
1333 | static bool isRead(AccessKinds AK) { | |||
1334 | return AK == AK_Read || AK == AK_ReadObjectRepresentation; | |||
1335 | } | |||
1336 | ||||
1337 | static bool isModification(AccessKinds AK) { | |||
1338 | switch (AK) { | |||
1339 | case AK_Read: | |||
1340 | case AK_ReadObjectRepresentation: | |||
1341 | case AK_MemberCall: | |||
1342 | case AK_DynamicCast: | |||
1343 | case AK_TypeId: | |||
1344 | return false; | |||
1345 | case AK_Assign: | |||
1346 | case AK_Increment: | |||
1347 | case AK_Decrement: | |||
1348 | case AK_Destroy: | |||
1349 | return true; | |||
1350 | } | |||
1351 | llvm_unreachable("unknown access kind")::llvm::llvm_unreachable_internal("unknown access kind", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1351); | |||
1352 | } | |||
1353 | ||||
1354 | static bool isAnyAccess(AccessKinds AK) { | |||
1355 | return isRead(AK) || isModification(AK); | |||
1356 | } | |||
1357 | ||||
1358 | /// Is this an access per the C++ definition? | |||
1359 | static bool isFormalAccess(AccessKinds AK) { | |||
1360 | return isAnyAccess(AK) && AK != AK_Destroy; | |||
1361 | } | |||
1362 | ||||
1363 | namespace { | |||
1364 | struct ComplexValue { | |||
1365 | private: | |||
1366 | bool IsInt; | |||
1367 | ||||
1368 | public: | |||
1369 | APSInt IntReal, IntImag; | |||
1370 | APFloat FloatReal, FloatImag; | |||
1371 | ||||
1372 | ComplexValue() : FloatReal(APFloat::Bogus()), FloatImag(APFloat::Bogus()) {} | |||
1373 | ||||
1374 | void makeComplexFloat() { IsInt = false; } | |||
1375 | bool isComplexFloat() const { return !IsInt; } | |||
1376 | APFloat &getComplexFloatReal() { return FloatReal; } | |||
1377 | APFloat &getComplexFloatImag() { return FloatImag; } | |||
1378 | ||||
1379 | void makeComplexInt() { IsInt = true; } | |||
1380 | bool isComplexInt() const { return IsInt; } | |||
1381 | APSInt &getComplexIntReal() { return IntReal; } | |||
1382 | APSInt &getComplexIntImag() { return IntImag; } | |||
1383 | ||||
1384 | void moveInto(APValue &v) const { | |||
1385 | if (isComplexFloat()) | |||
1386 | v = APValue(FloatReal, FloatImag); | |||
1387 | else | |||
1388 | v = APValue(IntReal, IntImag); | |||
1389 | } | |||
1390 | void setFrom(const APValue &v) { | |||
1391 | assert(v.isComplexFloat() || v.isComplexInt())((v.isComplexFloat() || v.isComplexInt()) ? static_cast<void > (0) : __assert_fail ("v.isComplexFloat() || v.isComplexInt()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1391, __PRETTY_FUNCTION__)); | |||
1392 | if (v.isComplexFloat()) { | |||
1393 | makeComplexFloat(); | |||
1394 | FloatReal = v.getComplexFloatReal(); | |||
1395 | FloatImag = v.getComplexFloatImag(); | |||
1396 | } else { | |||
1397 | makeComplexInt(); | |||
1398 | IntReal = v.getComplexIntReal(); | |||
1399 | IntImag = v.getComplexIntImag(); | |||
1400 | } | |||
1401 | } | |||
1402 | }; | |||
1403 | ||||
1404 | struct LValue { | |||
1405 | APValue::LValueBase Base; | |||
1406 | CharUnits Offset; | |||
1407 | SubobjectDesignator Designator; | |||
1408 | bool IsNullPtr : 1; | |||
1409 | bool InvalidBase : 1; | |||
1410 | ||||
1411 | const APValue::LValueBase getLValueBase() const { return Base; } | |||
1412 | CharUnits &getLValueOffset() { return Offset; } | |||
1413 | const CharUnits &getLValueOffset() const { return Offset; } | |||
1414 | SubobjectDesignator &getLValueDesignator() { return Designator; } | |||
1415 | const SubobjectDesignator &getLValueDesignator() const { return Designator;} | |||
1416 | bool isNullPointer() const { return IsNullPtr;} | |||
1417 | ||||
1418 | unsigned getLValueCallIndex() const { return Base.getCallIndex(); } | |||
1419 | unsigned getLValueVersion() const { return Base.getVersion(); } | |||
1420 | ||||
1421 | void moveInto(APValue &V) const { | |||
1422 | if (Designator.Invalid) | |||
1423 | V = APValue(Base, Offset, APValue::NoLValuePath(), IsNullPtr); | |||
1424 | else { | |||
1425 | assert(!InvalidBase && "APValues can't handle invalid LValue bases")((!InvalidBase && "APValues can't handle invalid LValue bases" ) ? static_cast<void> (0) : __assert_fail ("!InvalidBase && \"APValues can't handle invalid LValue bases\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1425, __PRETTY_FUNCTION__)); | |||
1426 | V = APValue(Base, Offset, Designator.Entries, | |||
1427 | Designator.IsOnePastTheEnd, IsNullPtr); | |||
1428 | } | |||
1429 | } | |||
1430 | void setFrom(ASTContext &Ctx, const APValue &V) { | |||
1431 | assert(V.isLValue() && "Setting LValue from a non-LValue?")((V.isLValue() && "Setting LValue from a non-LValue?" ) ? static_cast<void> (0) : __assert_fail ("V.isLValue() && \"Setting LValue from a non-LValue?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1431, __PRETTY_FUNCTION__)); | |||
1432 | Base = V.getLValueBase(); | |||
1433 | Offset = V.getLValueOffset(); | |||
1434 | InvalidBase = false; | |||
1435 | Designator = SubobjectDesignator(Ctx, V); | |||
1436 | IsNullPtr = V.isNullPointer(); | |||
1437 | } | |||
1438 | ||||
1439 | void set(APValue::LValueBase B, bool BInvalid = false) { | |||
1440 | #ifndef NDEBUG | |||
1441 | // We only allow a few types of invalid bases. Enforce that here. | |||
1442 | if (BInvalid) { | |||
1443 | const auto *E = B.get<const Expr *>(); | |||
1444 | assert((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) &&(((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) && "Unexpected type of invalid base") ? static_cast<void> (0) : __assert_fail ("(isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) && \"Unexpected type of invalid base\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1445, __PRETTY_FUNCTION__)) | |||
1445 | "Unexpected type of invalid base")(((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) && "Unexpected type of invalid base") ? static_cast<void> (0) : __assert_fail ("(isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) && \"Unexpected type of invalid base\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1445, __PRETTY_FUNCTION__)); | |||
1446 | } | |||
1447 | #endif | |||
1448 | ||||
1449 | Base = B; | |||
1450 | Offset = CharUnits::fromQuantity(0); | |||
1451 | InvalidBase = BInvalid; | |||
1452 | Designator = SubobjectDesignator(getType(B)); | |||
1453 | IsNullPtr = false; | |||
1454 | } | |||
1455 | ||||
1456 | void setNull(QualType PointerTy, uint64_t TargetVal) { | |||
1457 | Base = (Expr *)nullptr; | |||
1458 | Offset = CharUnits::fromQuantity(TargetVal); | |||
1459 | InvalidBase = false; | |||
1460 | Designator = SubobjectDesignator(PointerTy->getPointeeType()); | |||
1461 | IsNullPtr = true; | |||
1462 | } | |||
1463 | ||||
1464 | void setInvalid(APValue::LValueBase B, unsigned I = 0) { | |||
1465 | set(B, true); | |||
1466 | } | |||
1467 | ||||
1468 | private: | |||
1469 | // Check that this LValue is not based on a null pointer. If it is, produce | |||
1470 | // a diagnostic and mark the designator as invalid. | |||
1471 | template <typename GenDiagType> | |||
1472 | bool checkNullPointerDiagnosingWith(const GenDiagType &GenDiag) { | |||
1473 | if (Designator.Invalid) | |||
1474 | return false; | |||
1475 | if (IsNullPtr) { | |||
1476 | GenDiag(); | |||
1477 | Designator.setInvalid(); | |||
1478 | return false; | |||
1479 | } | |||
1480 | return true; | |||
1481 | } | |||
1482 | ||||
1483 | public: | |||
1484 | bool checkNullPointer(EvalInfo &Info, const Expr *E, | |||
1485 | CheckSubobjectKind CSK) { | |||
1486 | return checkNullPointerDiagnosingWith([&Info, E, CSK] { | |||
1487 | Info.CCEDiag(E, diag::note_constexpr_null_subobject) << CSK; | |||
1488 | }); | |||
1489 | } | |||
1490 | ||||
1491 | bool checkNullPointerForFoldAccess(EvalInfo &Info, const Expr *E, | |||
1492 | AccessKinds AK) { | |||
1493 | return checkNullPointerDiagnosingWith([&Info, E, AK] { | |||
1494 | Info.FFDiag(E, diag::note_constexpr_access_null) << AK; | |||
1495 | }); | |||
1496 | } | |||
1497 | ||||
1498 | // Check this LValue refers to an object. If not, set the designator to be | |||
1499 | // invalid and emit a diagnostic. | |||
1500 | bool checkSubobject(EvalInfo &Info, const Expr *E, CheckSubobjectKind CSK) { | |||
1501 | return (CSK == CSK_ArrayToPointer || checkNullPointer(Info, E, CSK)) && | |||
1502 | Designator.checkSubobject(Info, E, CSK); | |||
1503 | } | |||
1504 | ||||
1505 | void addDecl(EvalInfo &Info, const Expr *E, | |||
1506 | const Decl *D, bool Virtual = false) { | |||
1507 | if (checkSubobject(Info, E, isa<FieldDecl>(D) ? CSK_Field : CSK_Base)) | |||
1508 | Designator.addDeclUnchecked(D, Virtual); | |||
1509 | } | |||
1510 | void addUnsizedArray(EvalInfo &Info, const Expr *E, QualType ElemTy) { | |||
1511 | if (!Designator.Entries.empty()) { | |||
1512 | Info.CCEDiag(E, diag::note_constexpr_unsupported_unsized_array); | |||
1513 | Designator.setInvalid(); | |||
1514 | return; | |||
1515 | } | |||
1516 | if (checkSubobject(Info, E, CSK_ArrayToPointer)) { | |||
1517 | assert(getType(Base)->isPointerType() || getType(Base)->isArrayType())((getType(Base)->isPointerType() || getType(Base)->isArrayType ()) ? static_cast<void> (0) : __assert_fail ("getType(Base)->isPointerType() || getType(Base)->isArrayType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1517, __PRETTY_FUNCTION__)); | |||
1518 | Designator.FirstEntryIsAnUnsizedArray = true; | |||
1519 | Designator.addUnsizedArrayUnchecked(ElemTy); | |||
1520 | } | |||
1521 | } | |||
1522 | void addArray(EvalInfo &Info, const Expr *E, const ConstantArrayType *CAT) { | |||
1523 | if (checkSubobject(Info, E, CSK_ArrayToPointer)) | |||
1524 | Designator.addArrayUnchecked(CAT); | |||
1525 | } | |||
1526 | void addComplex(EvalInfo &Info, const Expr *E, QualType EltTy, bool Imag) { | |||
1527 | if (checkSubobject(Info, E, Imag ? CSK_Imag : CSK_Real)) | |||
1528 | Designator.addComplexUnchecked(EltTy, Imag); | |||
1529 | } | |||
1530 | void clearIsNullPointer() { | |||
1531 | IsNullPtr = false; | |||
1532 | } | |||
1533 | void adjustOffsetAndIndex(EvalInfo &Info, const Expr *E, | |||
1534 | const APSInt &Index, CharUnits ElementSize) { | |||
1535 | // An index of 0 has no effect. (In C, adding 0 to a null pointer is UB, | |||
1536 | // but we're not required to diagnose it and it's valid in C++.) | |||
1537 | if (!Index) | |||
1538 | return; | |||
1539 | ||||
1540 | // Compute the new offset in the appropriate width, wrapping at 64 bits. | |||
1541 | // FIXME: When compiling for a 32-bit target, we should use 32-bit | |||
1542 | // offsets. | |||
1543 | uint64_t Offset64 = Offset.getQuantity(); | |||
1544 | uint64_t ElemSize64 = ElementSize.getQuantity(); | |||
1545 | uint64_t Index64 = Index.extOrTrunc(64).getZExtValue(); | |||
1546 | Offset = CharUnits::fromQuantity(Offset64 + ElemSize64 * Index64); | |||
1547 | ||||
1548 | if (checkNullPointer(Info, E, CSK_ArrayIndex)) | |||
1549 | Designator.adjustIndex(Info, E, Index); | |||
1550 | clearIsNullPointer(); | |||
1551 | } | |||
1552 | void adjustOffset(CharUnits N) { | |||
1553 | Offset += N; | |||
1554 | if (N.getQuantity()) | |||
1555 | clearIsNullPointer(); | |||
1556 | } | |||
1557 | }; | |||
1558 | ||||
1559 | struct MemberPtr { | |||
1560 | MemberPtr() {} | |||
1561 | explicit MemberPtr(const ValueDecl *Decl) : | |||
1562 | DeclAndIsDerivedMember(Decl, false), Path() {} | |||
1563 | ||||
1564 | /// The member or (direct or indirect) field referred to by this member | |||
1565 | /// pointer, or 0 if this is a null member pointer. | |||
1566 | const ValueDecl *getDecl() const { | |||
1567 | return DeclAndIsDerivedMember.getPointer(); | |||
1568 | } | |||
1569 | /// Is this actually a member of some type derived from the relevant class? | |||
1570 | bool isDerivedMember() const { | |||
1571 | return DeclAndIsDerivedMember.getInt(); | |||
1572 | } | |||
1573 | /// Get the class which the declaration actually lives in. | |||
1574 | const CXXRecordDecl *getContainingRecord() const { | |||
1575 | return cast<CXXRecordDecl>( | |||
1576 | DeclAndIsDerivedMember.getPointer()->getDeclContext()); | |||
1577 | } | |||
1578 | ||||
1579 | void moveInto(APValue &V) const { | |||
1580 | V = APValue(getDecl(), isDerivedMember(), Path); | |||
1581 | } | |||
1582 | void setFrom(const APValue &V) { | |||
1583 | assert(V.isMemberPointer())((V.isMemberPointer()) ? static_cast<void> (0) : __assert_fail ("V.isMemberPointer()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1583, __PRETTY_FUNCTION__)); | |||
1584 | DeclAndIsDerivedMember.setPointer(V.getMemberPointerDecl()); | |||
1585 | DeclAndIsDerivedMember.setInt(V.isMemberPointerToDerivedMember()); | |||
1586 | Path.clear(); | |||
1587 | ArrayRef<const CXXRecordDecl*> P = V.getMemberPointerPath(); | |||
1588 | Path.insert(Path.end(), P.begin(), P.end()); | |||
1589 | } | |||
1590 | ||||
1591 | /// DeclAndIsDerivedMember - The member declaration, and a flag indicating | |||
1592 | /// whether the member is a member of some class derived from the class type | |||
1593 | /// of the member pointer. | |||
1594 | llvm::PointerIntPair<const ValueDecl*, 1, bool> DeclAndIsDerivedMember; | |||
1595 | /// Path - The path of base/derived classes from the member declaration's | |||
1596 | /// class (exclusive) to the class type of the member pointer (inclusive). | |||
1597 | SmallVector<const CXXRecordDecl*, 4> Path; | |||
1598 | ||||
1599 | /// Perform a cast towards the class of the Decl (either up or down the | |||
1600 | /// hierarchy). | |||
1601 | bool castBack(const CXXRecordDecl *Class) { | |||
1602 | assert(!Path.empty())((!Path.empty()) ? static_cast<void> (0) : __assert_fail ("!Path.empty()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1602, __PRETTY_FUNCTION__)); | |||
1603 | const CXXRecordDecl *Expected; | |||
1604 | if (Path.size() >= 2) | |||
1605 | Expected = Path[Path.size() - 2]; | |||
1606 | else | |||
1607 | Expected = getContainingRecord(); | |||
1608 | if (Expected->getCanonicalDecl() != Class->getCanonicalDecl()) { | |||
1609 | // C++11 [expr.static.cast]p12: In a conversion from (D::*) to (B::*), | |||
1610 | // if B does not contain the original member and is not a base or | |||
1611 | // derived class of the class containing the original member, the result | |||
1612 | // of the cast is undefined. | |||
1613 | // C++11 [conv.mem]p2 does not cover this case for a cast from (B::*) to | |||
1614 | // (D::*). We consider that to be a language defect. | |||
1615 | return false; | |||
1616 | } | |||
1617 | Path.pop_back(); | |||
1618 | return true; | |||
1619 | } | |||
1620 | /// Perform a base-to-derived member pointer cast. | |||
1621 | bool castToDerived(const CXXRecordDecl *Derived) { | |||
1622 | if (!getDecl()) | |||
1623 | return true; | |||
1624 | if (!isDerivedMember()) { | |||
1625 | Path.push_back(Derived); | |||
1626 | return true; | |||
1627 | } | |||
1628 | if (!castBack(Derived)) | |||
1629 | return false; | |||
1630 | if (Path.empty()) | |||
1631 | DeclAndIsDerivedMember.setInt(false); | |||
1632 | return true; | |||
1633 | } | |||
1634 | /// Perform a derived-to-base member pointer cast. | |||
1635 | bool castToBase(const CXXRecordDecl *Base) { | |||
1636 | if (!getDecl()) | |||
1637 | return true; | |||
1638 | if (Path.empty()) | |||
1639 | DeclAndIsDerivedMember.setInt(true); | |||
1640 | if (isDerivedMember()) { | |||
1641 | Path.push_back(Base); | |||
1642 | return true; | |||
1643 | } | |||
1644 | return castBack(Base); | |||
1645 | } | |||
1646 | }; | |||
1647 | ||||
1648 | /// Compare two member pointers, which are assumed to be of the same type. | |||
1649 | static bool operator==(const MemberPtr &LHS, const MemberPtr &RHS) { | |||
1650 | if (!LHS.getDecl() || !RHS.getDecl()) | |||
1651 | return !LHS.getDecl() && !RHS.getDecl(); | |||
1652 | if (LHS.getDecl()->getCanonicalDecl() != RHS.getDecl()->getCanonicalDecl()) | |||
1653 | return false; | |||
1654 | return LHS.Path == RHS.Path; | |||
1655 | } | |||
1656 | } | |||
1657 | ||||
1658 | static bool Evaluate(APValue &Result, EvalInfo &Info, const Expr *E); | |||
1659 | static bool EvaluateInPlace(APValue &Result, EvalInfo &Info, | |||
1660 | const LValue &This, const Expr *E, | |||
1661 | bool AllowNonLiteralTypes = false); | |||
1662 | static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info, | |||
1663 | bool InvalidBaseOK = false); | |||
1664 | static bool EvaluatePointer(const Expr *E, LValue &Result, EvalInfo &Info, | |||
1665 | bool InvalidBaseOK = false); | |||
1666 | static bool EvaluateMemberPointer(const Expr *E, MemberPtr &Result, | |||
1667 | EvalInfo &Info); | |||
1668 | static bool EvaluateTemporary(const Expr *E, LValue &Result, EvalInfo &Info); | |||
1669 | static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info); | |||
1670 | static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result, | |||
1671 | EvalInfo &Info); | |||
1672 | static bool EvaluateFloat(const Expr *E, APFloat &Result, EvalInfo &Info); | |||
1673 | static bool EvaluateComplex(const Expr *E, ComplexValue &Res, EvalInfo &Info); | |||
1674 | static bool EvaluateAtomic(const Expr *E, const LValue *This, APValue &Result, | |||
1675 | EvalInfo &Info); | |||
1676 | static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result); | |||
1677 | ||||
1678 | /// Evaluate an integer or fixed point expression into an APResult. | |||
1679 | static bool EvaluateFixedPointOrInteger(const Expr *E, APFixedPoint &Result, | |||
1680 | EvalInfo &Info); | |||
1681 | ||||
1682 | /// Evaluate only a fixed point expression into an APResult. | |||
1683 | static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result, | |||
1684 | EvalInfo &Info); | |||
1685 | ||||
1686 | //===----------------------------------------------------------------------===// | |||
1687 | // Misc utilities | |||
1688 | //===----------------------------------------------------------------------===// | |||
1689 | ||||
1690 | /// Negate an APSInt in place, converting it to a signed form if necessary, and | |||
1691 | /// preserving its value (by extending by up to one bit as needed). | |||
1692 | static void negateAsSigned(APSInt &Int) { | |||
1693 | if (Int.isUnsigned() || Int.isMinSignedValue()) { | |||
1694 | Int = Int.extend(Int.getBitWidth() + 1); | |||
1695 | Int.setIsSigned(true); | |||
1696 | } | |||
1697 | Int = -Int; | |||
1698 | } | |||
1699 | ||||
1700 | template<typename KeyT> | |||
1701 | APValue &CallStackFrame::createTemporary(const KeyT *Key, QualType T, | |||
1702 | bool IsLifetimeExtended, LValue &LV) { | |||
1703 | unsigned Version = getTempVersion(); | |||
1704 | APValue::LValueBase Base(Key, Index, Version); | |||
1705 | LV.set(Base); | |||
1706 | APValue &Result = Temporaries[MapKeyTy(Key, Version)]; | |||
1707 | assert(Result.isAbsent() && "temporary created multiple times")((Result.isAbsent() && "temporary created multiple times" ) ? static_cast<void> (0) : __assert_fail ("Result.isAbsent() && \"temporary created multiple times\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1707, __PRETTY_FUNCTION__)); | |||
1708 | ||||
1709 | // If we're creating a temporary immediately in the operand of a speculative | |||
1710 | // evaluation, don't register a cleanup to be run outside the speculative | |||
1711 | // evaluation context, since we won't actually be able to initialize this | |||
1712 | // object. | |||
1713 | if (Index <= Info.SpeculativeEvaluationDepth) { | |||
1714 | if (T.isDestructedType()) | |||
1715 | Info.noteSideEffect(); | |||
1716 | } else { | |||
1717 | Info.CleanupStack.push_back(Cleanup(&Result, Base, T, IsLifetimeExtended)); | |||
1718 | } | |||
1719 | return Result; | |||
1720 | } | |||
1721 | ||||
1722 | APValue *EvalInfo::createHeapAlloc(const Expr *E, QualType T, LValue &LV) { | |||
1723 | if (NumHeapAllocs > DynamicAllocLValue::getMaxIndex()) { | |||
1724 | FFDiag(E, diag::note_constexpr_heap_alloc_limit_exceeded); | |||
1725 | return nullptr; | |||
1726 | } | |||
1727 | ||||
1728 | DynamicAllocLValue DA(NumHeapAllocs++); | |||
1729 | LV.set(APValue::LValueBase::getDynamicAlloc(DA, T)); | |||
1730 | auto Result = HeapAllocs.emplace(std::piecewise_construct, | |||
1731 | std::forward_as_tuple(DA), std::tuple<>()); | |||
1732 | assert(Result.second && "reused a heap alloc index?")((Result.second && "reused a heap alloc index?") ? static_cast <void> (0) : __assert_fail ("Result.second && \"reused a heap alloc index?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1732, __PRETTY_FUNCTION__)); | |||
1733 | Result.first->second.AllocExpr = E; | |||
1734 | return &Result.first->second.Value; | |||
1735 | } | |||
1736 | ||||
1737 | /// Produce a string describing the given constexpr call. | |||
1738 | void CallStackFrame::describe(raw_ostream &Out) { | |||
1739 | unsigned ArgIndex = 0; | |||
1740 | bool IsMemberCall = isa<CXXMethodDecl>(Callee) && | |||
1741 | !isa<CXXConstructorDecl>(Callee) && | |||
1742 | cast<CXXMethodDecl>(Callee)->isInstance(); | |||
1743 | ||||
1744 | if (!IsMemberCall) | |||
1745 | Out << *Callee << '('; | |||
1746 | ||||
1747 | if (This && IsMemberCall) { | |||
1748 | APValue Val; | |||
1749 | This->moveInto(Val); | |||
1750 | Val.printPretty(Out, Info.Ctx, | |||
1751 | This->Designator.MostDerivedType); | |||
1752 | // FIXME: Add parens around Val if needed. | |||
1753 | Out << "->" << *Callee << '('; | |||
1754 | IsMemberCall = false; | |||
1755 | } | |||
1756 | ||||
1757 | for (FunctionDecl::param_const_iterator I = Callee->param_begin(), | |||
1758 | E = Callee->param_end(); I != E; ++I, ++ArgIndex) { | |||
1759 | if (ArgIndex > (unsigned)IsMemberCall) | |||
1760 | Out << ", "; | |||
1761 | ||||
1762 | const ParmVarDecl *Param = *I; | |||
1763 | const APValue &Arg = Arguments[ArgIndex]; | |||
1764 | Arg.printPretty(Out, Info.Ctx, Param->getType()); | |||
1765 | ||||
1766 | if (ArgIndex == 0 && IsMemberCall) | |||
1767 | Out << "->" << *Callee << '('; | |||
1768 | } | |||
1769 | ||||
1770 | Out << ')'; | |||
1771 | } | |||
1772 | ||||
1773 | /// Evaluate an expression to see if it had side-effects, and discard its | |||
1774 | /// result. | |||
1775 | /// \return \c true if the caller should keep evaluating. | |||
1776 | static bool EvaluateIgnoredValue(EvalInfo &Info, const Expr *E) { | |||
1777 | APValue Scratch; | |||
1778 | if (!Evaluate(Scratch, Info, E)) | |||
1779 | // We don't need the value, but we might have skipped a side effect here. | |||
1780 | return Info.noteSideEffect(); | |||
1781 | return true; | |||
1782 | } | |||
1783 | ||||
1784 | /// Should this call expression be treated as a string literal? | |||
1785 | static bool IsStringLiteralCall(const CallExpr *E) { | |||
1786 | unsigned Builtin = E->getBuiltinCallee(); | |||
1787 | return (Builtin == Builtin::BI__builtin___CFStringMakeConstantString || | |||
1788 | Builtin == Builtin::BI__builtin___NSStringMakeConstantString); | |||
1789 | } | |||
1790 | ||||
1791 | static bool IsGlobalLValue(APValue::LValueBase B) { | |||
1792 | // C++11 [expr.const]p3 An address constant expression is a prvalue core | |||
1793 | // constant expression of pointer type that evaluates to... | |||
1794 | ||||
1795 | // ... a null pointer value, or a prvalue core constant expression of type | |||
1796 | // std::nullptr_t. | |||
1797 | if (!B) return true; | |||
1798 | ||||
1799 | if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) { | |||
1800 | // ... the address of an object with static storage duration, | |||
1801 | if (const VarDecl *VD = dyn_cast<VarDecl>(D)) | |||
1802 | return VD->hasGlobalStorage(); | |||
1803 | // ... the address of a function, | |||
1804 | return isa<FunctionDecl>(D); | |||
1805 | } | |||
1806 | ||||
1807 | if (B.is<TypeInfoLValue>() || B.is<DynamicAllocLValue>()) | |||
1808 | return true; | |||
1809 | ||||
1810 | const Expr *E = B.get<const Expr*>(); | |||
1811 | switch (E->getStmtClass()) { | |||
1812 | default: | |||
1813 | return false; | |||
1814 | case Expr::CompoundLiteralExprClass: { | |||
1815 | const CompoundLiteralExpr *CLE = cast<CompoundLiteralExpr>(E); | |||
1816 | return CLE->isFileScope() && CLE->isLValue(); | |||
1817 | } | |||
1818 | case Expr::MaterializeTemporaryExprClass: | |||
1819 | // A materialized temporary might have been lifetime-extended to static | |||
1820 | // storage duration. | |||
1821 | return cast<MaterializeTemporaryExpr>(E)->getStorageDuration() == SD_Static; | |||
1822 | // A string literal has static storage duration. | |||
1823 | case Expr::StringLiteralClass: | |||
1824 | case Expr::PredefinedExprClass: | |||
1825 | case Expr::ObjCStringLiteralClass: | |||
1826 | case Expr::ObjCEncodeExprClass: | |||
1827 | case Expr::CXXUuidofExprClass: | |||
1828 | return true; | |||
1829 | case Expr::ObjCBoxedExprClass: | |||
1830 | return cast<ObjCBoxedExpr>(E)->isExpressibleAsConstantInitializer(); | |||
1831 | case Expr::CallExprClass: | |||
1832 | return IsStringLiteralCall(cast<CallExpr>(E)); | |||
1833 | // For GCC compatibility, &&label has static storage duration. | |||
1834 | case Expr::AddrLabelExprClass: | |||
1835 | return true; | |||
1836 | // A Block literal expression may be used as the initialization value for | |||
1837 | // Block variables at global or local static scope. | |||
1838 | case Expr::BlockExprClass: | |||
1839 | return !cast<BlockExpr>(E)->getBlockDecl()->hasCaptures(); | |||
1840 | case Expr::ImplicitValueInitExprClass: | |||
1841 | // FIXME: | |||
1842 | // We can never form an lvalue with an implicit value initialization as its | |||
1843 | // base through expression evaluation, so these only appear in one case: the | |||
1844 | // implicit variable declaration we invent when checking whether a constexpr | |||
1845 | // constructor can produce a constant expression. We must assume that such | |||
1846 | // an expression might be a global lvalue. | |||
1847 | return true; | |||
1848 | } | |||
1849 | } | |||
1850 | ||||
1851 | static const ValueDecl *GetLValueBaseDecl(const LValue &LVal) { | |||
1852 | return LVal.Base.dyn_cast<const ValueDecl*>(); | |||
1853 | } | |||
1854 | ||||
1855 | static bool IsLiteralLValue(const LValue &Value) { | |||
1856 | if (Value.getLValueCallIndex()) | |||
1857 | return false; | |||
1858 | const Expr *E = Value.Base.dyn_cast<const Expr*>(); | |||
1859 | return E && !isa<MaterializeTemporaryExpr>(E); | |||
1860 | } | |||
1861 | ||||
1862 | static bool IsWeakLValue(const LValue &Value) { | |||
1863 | const ValueDecl *Decl = GetLValueBaseDecl(Value); | |||
1864 | return Decl && Decl->isWeak(); | |||
1865 | } | |||
1866 | ||||
1867 | static bool isZeroSized(const LValue &Value) { | |||
1868 | const ValueDecl *Decl = GetLValueBaseDecl(Value); | |||
1869 | if (Decl && isa<VarDecl>(Decl)) { | |||
1870 | QualType Ty = Decl->getType(); | |||
1871 | if (Ty->isArrayType()) | |||
1872 | return Ty->isIncompleteType() || | |||
1873 | Decl->getASTContext().getTypeSize(Ty) == 0; | |||
1874 | } | |||
1875 | return false; | |||
1876 | } | |||
1877 | ||||
1878 | static bool HasSameBase(const LValue &A, const LValue &B) { | |||
1879 | if (!A.getLValueBase()) | |||
1880 | return !B.getLValueBase(); | |||
1881 | if (!B.getLValueBase()) | |||
1882 | return false; | |||
1883 | ||||
1884 | if (A.getLValueBase().getOpaqueValue() != | |||
1885 | B.getLValueBase().getOpaqueValue()) { | |||
1886 | const Decl *ADecl = GetLValueBaseDecl(A); | |||
1887 | if (!ADecl) | |||
1888 | return false; | |||
1889 | const Decl *BDecl = GetLValueBaseDecl(B); | |||
1890 | if (!BDecl || ADecl->getCanonicalDecl() != BDecl->getCanonicalDecl()) | |||
1891 | return false; | |||
1892 | } | |||
1893 | ||||
1894 | return IsGlobalLValue(A.getLValueBase()) || | |||
1895 | (A.getLValueCallIndex() == B.getLValueCallIndex() && | |||
1896 | A.getLValueVersion() == B.getLValueVersion()); | |||
1897 | } | |||
1898 | ||||
1899 | static void NoteLValueLocation(EvalInfo &Info, APValue::LValueBase Base) { | |||
1900 | assert(Base && "no location for a null lvalue")((Base && "no location for a null lvalue") ? static_cast <void> (0) : __assert_fail ("Base && \"no location for a null lvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1900, __PRETTY_FUNCTION__)); | |||
1901 | const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>(); | |||
1902 | if (VD) | |||
1903 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
1904 | else if (const Expr *E = Base.dyn_cast<const Expr*>()) | |||
1905 | Info.Note(E->getExprLoc(), diag::note_constexpr_temporary_here); | |||
1906 | else if (DynamicAllocLValue DA = Base.dyn_cast<DynamicAllocLValue>()) { | |||
1907 | // FIXME: Produce a note for dangling pointers too. | |||
1908 | if (Optional<EvalInfo::DynAlloc*> Alloc = Info.lookupDynamicAlloc(DA)) | |||
1909 | Info.Note((*Alloc)->AllocExpr->getExprLoc(), | |||
1910 | diag::note_constexpr_dynamic_alloc_here); | |||
1911 | } | |||
1912 | // We have no information to show for a typeid(T) object. | |||
1913 | } | |||
1914 | ||||
1915 | enum class CheckEvaluationResultKind { | |||
1916 | ConstantExpression, | |||
1917 | FullyInitialized, | |||
1918 | }; | |||
1919 | ||||
1920 | /// Materialized temporaries that we've already checked to determine if they're | |||
1921 | /// initializsed by a constant expression. | |||
1922 | using CheckedTemporaries = | |||
1923 | llvm::SmallPtrSet<const MaterializeTemporaryExpr *, 8>; | |||
1924 | ||||
1925 | static bool CheckEvaluationResult(CheckEvaluationResultKind CERK, | |||
1926 | EvalInfo &Info, SourceLocation DiagLoc, | |||
1927 | QualType Type, const APValue &Value, | |||
1928 | Expr::ConstExprUsage Usage, | |||
1929 | SourceLocation SubobjectLoc, | |||
1930 | CheckedTemporaries &CheckedTemps); | |||
1931 | ||||
1932 | /// Check that this reference or pointer core constant expression is a valid | |||
1933 | /// value for an address or reference constant expression. Return true if we | |||
1934 | /// can fold this expression, whether or not it's a constant expression. | |||
1935 | static bool CheckLValueConstantExpression(EvalInfo &Info, SourceLocation Loc, | |||
1936 | QualType Type, const LValue &LVal, | |||
1937 | Expr::ConstExprUsage Usage, | |||
1938 | CheckedTemporaries &CheckedTemps) { | |||
1939 | bool IsReferenceType = Type->isReferenceType(); | |||
1940 | ||||
1941 | APValue::LValueBase Base = LVal.getLValueBase(); | |||
1942 | const SubobjectDesignator &Designator = LVal.getLValueDesignator(); | |||
1943 | ||||
1944 | // Check that the object is a global. Note that the fake 'this' object we | |||
1945 | // manufacture when checking potential constant expressions is conservatively | |||
1946 | // assumed to be global here. | |||
1947 | if (!IsGlobalLValue(Base)) { | |||
1948 | if (Info.getLangOpts().CPlusPlus11) { | |||
1949 | const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>(); | |||
1950 | Info.FFDiag(Loc, diag::note_constexpr_non_global, 1) | |||
1951 | << IsReferenceType << !Designator.Entries.empty() | |||
1952 | << !!VD << VD; | |||
1953 | NoteLValueLocation(Info, Base); | |||
1954 | } else { | |||
1955 | Info.FFDiag(Loc); | |||
1956 | } | |||
1957 | // Don't allow references to temporaries to escape. | |||
1958 | return false; | |||
1959 | } | |||
1960 | assert((Info.checkingPotentialConstantExpression() ||(((Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex () == 0) && "have call index for global lvalue") ? static_cast <void> (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1962, __PRETTY_FUNCTION__)) | |||
1961 | LVal.getLValueCallIndex() == 0) &&(((Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex () == 0) && "have call index for global lvalue") ? static_cast <void> (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1962, __PRETTY_FUNCTION__)) | |||
1962 | "have call index for global lvalue")(((Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex () == 0) && "have call index for global lvalue") ? static_cast <void> (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 1962, __PRETTY_FUNCTION__)); | |||
1963 | ||||
1964 | if (Base.is<DynamicAllocLValue>()) { | |||
1965 | Info.FFDiag(Loc, diag::note_constexpr_dynamic_alloc) | |||
1966 | << IsReferenceType << !Designator.Entries.empty(); | |||
1967 | NoteLValueLocation(Info, Base); | |||
1968 | return false; | |||
1969 | } | |||
1970 | ||||
1971 | if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>()) { | |||
1972 | if (const VarDecl *Var = dyn_cast<const VarDecl>(VD)) { | |||
1973 | // Check if this is a thread-local variable. | |||
1974 | if (Var->getTLSKind()) | |||
1975 | // FIXME: Diagnostic! | |||
1976 | return false; | |||
1977 | ||||
1978 | // A dllimport variable never acts like a constant. | |||
1979 | if (Usage == Expr::EvaluateForCodeGen && Var->hasAttr<DLLImportAttr>()) | |||
1980 | // FIXME: Diagnostic! | |||
1981 | return false; | |||
1982 | } | |||
1983 | if (const auto *FD = dyn_cast<const FunctionDecl>(VD)) { | |||
1984 | // __declspec(dllimport) must be handled very carefully: | |||
1985 | // We must never initialize an expression with the thunk in C++. | |||
1986 | // Doing otherwise would allow the same id-expression to yield | |||
1987 | // different addresses for the same function in different translation | |||
1988 | // units. However, this means that we must dynamically initialize the | |||
1989 | // expression with the contents of the import address table at runtime. | |||
1990 | // | |||
1991 | // The C language has no notion of ODR; furthermore, it has no notion of | |||
1992 | // dynamic initialization. This means that we are permitted to | |||
1993 | // perform initialization with the address of the thunk. | |||
1994 | if (Info.getLangOpts().CPlusPlus && Usage == Expr::EvaluateForCodeGen && | |||
1995 | FD->hasAttr<DLLImportAttr>()) | |||
1996 | // FIXME: Diagnostic! | |||
1997 | return false; | |||
1998 | } | |||
1999 | } else if (const auto *MTE = dyn_cast_or_null<MaterializeTemporaryExpr>( | |||
2000 | Base.dyn_cast<const Expr *>())) { | |||
2001 | if (CheckedTemps.insert(MTE).second) { | |||
2002 | QualType TempType = getType(Base); | |||
2003 | if (TempType.isDestructedType()) { | |||
2004 | Info.FFDiag(MTE->getExprLoc(), | |||
2005 | diag::note_constexpr_unsupported_tempoarary_nontrivial_dtor) | |||
2006 | << TempType; | |||
2007 | return false; | |||
2008 | } | |||
2009 | ||||
2010 | APValue *V = Info.Ctx.getMaterializedTemporaryValue(MTE, false); | |||
2011 | assert(V && "evasluation result refers to uninitialised temporary")((V && "evasluation result refers to uninitialised temporary" ) ? static_cast<void> (0) : __assert_fail ("V && \"evasluation result refers to uninitialised temporary\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2011, __PRETTY_FUNCTION__)); | |||
2012 | if (!CheckEvaluationResult(CheckEvaluationResultKind::ConstantExpression, | |||
2013 | Info, MTE->getExprLoc(), TempType, *V, | |||
2014 | Usage, SourceLocation(), CheckedTemps)) | |||
2015 | return false; | |||
2016 | } | |||
2017 | } | |||
2018 | ||||
2019 | // Allow address constant expressions to be past-the-end pointers. This is | |||
2020 | // an extension: the standard requires them to point to an object. | |||
2021 | if (!IsReferenceType) | |||
2022 | return true; | |||
2023 | ||||
2024 | // A reference constant expression must refer to an object. | |||
2025 | if (!Base) { | |||
2026 | // FIXME: diagnostic | |||
2027 | Info.CCEDiag(Loc); | |||
2028 | return true; | |||
2029 | } | |||
2030 | ||||
2031 | // Does this refer one past the end of some object? | |||
2032 | if (!Designator.Invalid && Designator.isOnePastTheEnd()) { | |||
2033 | const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>(); | |||
2034 | Info.FFDiag(Loc, diag::note_constexpr_past_end, 1) | |||
2035 | << !Designator.Entries.empty() << !!VD << VD; | |||
2036 | NoteLValueLocation(Info, Base); | |||
2037 | } | |||
2038 | ||||
2039 | return true; | |||
2040 | } | |||
2041 | ||||
2042 | /// Member pointers are constant expressions unless they point to a | |||
2043 | /// non-virtual dllimport member function. | |||
2044 | static bool CheckMemberPointerConstantExpression(EvalInfo &Info, | |||
2045 | SourceLocation Loc, | |||
2046 | QualType Type, | |||
2047 | const APValue &Value, | |||
2048 | Expr::ConstExprUsage Usage) { | |||
2049 | const ValueDecl *Member = Value.getMemberPointerDecl(); | |||
2050 | const auto *FD = dyn_cast_or_null<CXXMethodDecl>(Member); | |||
2051 | if (!FD) | |||
2052 | return true; | |||
2053 | return Usage == Expr::EvaluateForMangling || FD->isVirtual() || | |||
2054 | !FD->hasAttr<DLLImportAttr>(); | |||
2055 | } | |||
2056 | ||||
2057 | /// Check that this core constant expression is of literal type, and if not, | |||
2058 | /// produce an appropriate diagnostic. | |||
2059 | static bool CheckLiteralType(EvalInfo &Info, const Expr *E, | |||
2060 | const LValue *This = nullptr) { | |||
2061 | if (!E->isRValue() || E->getType()->isLiteralType(Info.Ctx)) | |||
2062 | return true; | |||
2063 | ||||
2064 | // C++1y: A constant initializer for an object o [...] may also invoke | |||
2065 | // constexpr constructors for o and its subobjects even if those objects | |||
2066 | // are of non-literal class types. | |||
2067 | // | |||
2068 | // C++11 missed this detail for aggregates, so classes like this: | |||
2069 | // struct foo_t { union { int i; volatile int j; } u; }; | |||
2070 | // are not (obviously) initializable like so: | |||
2071 | // __attribute__((__require_constant_initialization__)) | |||
2072 | // static const foo_t x = {{0}}; | |||
2073 | // because "i" is a subobject with non-literal initialization (due to the | |||
2074 | // volatile member of the union). See: | |||
2075 | // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1677 | |||
2076 | // Therefore, we use the C++1y behavior. | |||
2077 | if (This && Info.EvaluatingDecl == This->getLValueBase()) | |||
2078 | return true; | |||
2079 | ||||
2080 | // Prvalue constant expressions must be of literal types. | |||
2081 | if (Info.getLangOpts().CPlusPlus11) | |||
2082 | Info.FFDiag(E, diag::note_constexpr_nonliteral) | |||
2083 | << E->getType(); | |||
2084 | else | |||
2085 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
2086 | return false; | |||
2087 | } | |||
2088 | ||||
2089 | static bool CheckEvaluationResult(CheckEvaluationResultKind CERK, | |||
2090 | EvalInfo &Info, SourceLocation DiagLoc, | |||
2091 | QualType Type, const APValue &Value, | |||
2092 | Expr::ConstExprUsage Usage, | |||
2093 | SourceLocation SubobjectLoc, | |||
2094 | CheckedTemporaries &CheckedTemps) { | |||
2095 | if (!Value.hasValue()) { | |||
2096 | Info.FFDiag(DiagLoc, diag::note_constexpr_uninitialized) | |||
2097 | << true << Type; | |||
2098 | if (SubobjectLoc.isValid()) | |||
2099 | Info.Note(SubobjectLoc, diag::note_constexpr_subobject_declared_here); | |||
2100 | return false; | |||
2101 | } | |||
2102 | ||||
2103 | // We allow _Atomic(T) to be initialized from anything that T can be | |||
2104 | // initialized from. | |||
2105 | if (const AtomicType *AT = Type->getAs<AtomicType>()) | |||
2106 | Type = AT->getValueType(); | |||
2107 | ||||
2108 | // Core issue 1454: For a literal constant expression of array or class type, | |||
2109 | // each subobject of its value shall have been initialized by a constant | |||
2110 | // expression. | |||
2111 | if (Value.isArray()) { | |||
2112 | QualType EltTy = Type->castAsArrayTypeUnsafe()->getElementType(); | |||
2113 | for (unsigned I = 0, N = Value.getArrayInitializedElts(); I != N; ++I) { | |||
2114 | if (!CheckEvaluationResult(CERK, Info, DiagLoc, EltTy, | |||
2115 | Value.getArrayInitializedElt(I), Usage, | |||
2116 | SubobjectLoc, CheckedTemps)) | |||
2117 | return false; | |||
2118 | } | |||
2119 | if (!Value.hasArrayFiller()) | |||
2120 | return true; | |||
2121 | return CheckEvaluationResult(CERK, Info, DiagLoc, EltTy, | |||
2122 | Value.getArrayFiller(), Usage, SubobjectLoc, | |||
2123 | CheckedTemps); | |||
2124 | } | |||
2125 | if (Value.isUnion() && Value.getUnionField()) { | |||
2126 | return CheckEvaluationResult( | |||
2127 | CERK, Info, DiagLoc, Value.getUnionField()->getType(), | |||
2128 | Value.getUnionValue(), Usage, Value.getUnionField()->getLocation(), | |||
2129 | CheckedTemps); | |||
2130 | } | |||
2131 | if (Value.isStruct()) { | |||
2132 | RecordDecl *RD = Type->castAs<RecordType>()->getDecl(); | |||
2133 | if (const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD)) { | |||
2134 | unsigned BaseIndex = 0; | |||
2135 | for (const CXXBaseSpecifier &BS : CD->bases()) { | |||
2136 | if (!CheckEvaluationResult(CERK, Info, DiagLoc, BS.getType(), | |||
2137 | Value.getStructBase(BaseIndex), Usage, | |||
2138 | BS.getBeginLoc(), CheckedTemps)) | |||
2139 | return false; | |||
2140 | ++BaseIndex; | |||
2141 | } | |||
2142 | } | |||
2143 | for (const auto *I : RD->fields()) { | |||
2144 | if (I->isUnnamedBitfield()) | |||
2145 | continue; | |||
2146 | ||||
2147 | if (!CheckEvaluationResult(CERK, Info, DiagLoc, I->getType(), | |||
2148 | Value.getStructField(I->getFieldIndex()), | |||
2149 | Usage, I->getLocation(), CheckedTemps)) | |||
2150 | return false; | |||
2151 | } | |||
2152 | } | |||
2153 | ||||
2154 | if (Value.isLValue() && | |||
2155 | CERK == CheckEvaluationResultKind::ConstantExpression) { | |||
2156 | LValue LVal; | |||
2157 | LVal.setFrom(Info.Ctx, Value); | |||
2158 | return CheckLValueConstantExpression(Info, DiagLoc, Type, LVal, Usage, | |||
2159 | CheckedTemps); | |||
2160 | } | |||
2161 | ||||
2162 | if (Value.isMemberPointer() && | |||
2163 | CERK == CheckEvaluationResultKind::ConstantExpression) | |||
2164 | return CheckMemberPointerConstantExpression(Info, DiagLoc, Type, Value, Usage); | |||
2165 | ||||
2166 | // Everything else is fine. | |||
2167 | return true; | |||
2168 | } | |||
2169 | ||||
2170 | /// Check that this core constant expression value is a valid value for a | |||
2171 | /// constant expression. If not, report an appropriate diagnostic. Does not | |||
2172 | /// check that the expression is of literal type. | |||
2173 | static bool | |||
2174 | CheckConstantExpression(EvalInfo &Info, SourceLocation DiagLoc, QualType Type, | |||
2175 | const APValue &Value, | |||
2176 | Expr::ConstExprUsage Usage = Expr::EvaluateForCodeGen) { | |||
2177 | CheckedTemporaries CheckedTemps; | |||
2178 | return CheckEvaluationResult(CheckEvaluationResultKind::ConstantExpression, | |||
2179 | Info, DiagLoc, Type, Value, Usage, | |||
2180 | SourceLocation(), CheckedTemps); | |||
2181 | } | |||
2182 | ||||
2183 | /// Check that this evaluated value is fully-initialized and can be loaded by | |||
2184 | /// an lvalue-to-rvalue conversion. | |||
2185 | static bool CheckFullyInitialized(EvalInfo &Info, SourceLocation DiagLoc, | |||
2186 | QualType Type, const APValue &Value) { | |||
2187 | CheckedTemporaries CheckedTemps; | |||
2188 | return CheckEvaluationResult( | |||
2189 | CheckEvaluationResultKind::FullyInitialized, Info, DiagLoc, Type, Value, | |||
2190 | Expr::EvaluateForCodeGen, SourceLocation(), CheckedTemps); | |||
2191 | } | |||
2192 | ||||
2193 | /// Enforce C++2a [expr.const]/4.17, which disallows new-expressions unless | |||
2194 | /// "the allocated storage is deallocated within the evaluation". | |||
2195 | static bool CheckMemoryLeaks(EvalInfo &Info) { | |||
2196 | if (!Info.HeapAllocs.empty()) { | |||
2197 | // We can still fold to a constant despite a compile-time memory leak, | |||
2198 | // so long as the heap allocation isn't referenced in the result (we check | |||
2199 | // that in CheckConstantExpression). | |||
2200 | Info.CCEDiag(Info.HeapAllocs.begin()->second.AllocExpr, | |||
2201 | diag::note_constexpr_memory_leak) | |||
2202 | << unsigned(Info.HeapAllocs.size() - 1); | |||
2203 | } | |||
2204 | return true; | |||
2205 | } | |||
2206 | ||||
2207 | static bool EvalPointerValueAsBool(const APValue &Value, bool &Result) { | |||
2208 | // A null base expression indicates a null pointer. These are always | |||
2209 | // evaluatable, and they are false unless the offset is zero. | |||
2210 | if (!Value.getLValueBase()) { | |||
2211 | Result = !Value.getLValueOffset().isZero(); | |||
2212 | return true; | |||
2213 | } | |||
2214 | ||||
2215 | // We have a non-null base. These are generally known to be true, but if it's | |||
2216 | // a weak declaration it can be null at runtime. | |||
2217 | Result = true; | |||
2218 | const ValueDecl *Decl = Value.getLValueBase().dyn_cast<const ValueDecl*>(); | |||
2219 | return !Decl || !Decl->isWeak(); | |||
2220 | } | |||
2221 | ||||
2222 | static bool HandleConversionToBool(const APValue &Val, bool &Result) { | |||
2223 | switch (Val.getKind()) { | |||
2224 | case APValue::None: | |||
2225 | case APValue::Indeterminate: | |||
2226 | return false; | |||
2227 | case APValue::Int: | |||
2228 | Result = Val.getInt().getBoolValue(); | |||
2229 | return true; | |||
2230 | case APValue::FixedPoint: | |||
2231 | Result = Val.getFixedPoint().getBoolValue(); | |||
2232 | return true; | |||
2233 | case APValue::Float: | |||
2234 | Result = !Val.getFloat().isZero(); | |||
2235 | return true; | |||
2236 | case APValue::ComplexInt: | |||
2237 | Result = Val.getComplexIntReal().getBoolValue() || | |||
2238 | Val.getComplexIntImag().getBoolValue(); | |||
2239 | return true; | |||
2240 | case APValue::ComplexFloat: | |||
2241 | Result = !Val.getComplexFloatReal().isZero() || | |||
2242 | !Val.getComplexFloatImag().isZero(); | |||
2243 | return true; | |||
2244 | case APValue::LValue: | |||
2245 | return EvalPointerValueAsBool(Val, Result); | |||
2246 | case APValue::MemberPointer: | |||
2247 | Result = Val.getMemberPointerDecl(); | |||
2248 | return true; | |||
2249 | case APValue::Vector: | |||
2250 | case APValue::Array: | |||
2251 | case APValue::Struct: | |||
2252 | case APValue::Union: | |||
2253 | case APValue::AddrLabelDiff: | |||
2254 | return false; | |||
2255 | } | |||
2256 | ||||
2257 | llvm_unreachable("unknown APValue kind")::llvm::llvm_unreachable_internal("unknown APValue kind", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2257); | |||
2258 | } | |||
2259 | ||||
2260 | static bool EvaluateAsBooleanCondition(const Expr *E, bool &Result, | |||
2261 | EvalInfo &Info) { | |||
2262 | assert(E->isRValue() && "missing lvalue-to-rvalue conv in bool condition")((E->isRValue() && "missing lvalue-to-rvalue conv in bool condition" ) ? static_cast<void> (0) : __assert_fail ("E->isRValue() && \"missing lvalue-to-rvalue conv in bool condition\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2262, __PRETTY_FUNCTION__)); | |||
2263 | APValue Val; | |||
2264 | if (!Evaluate(Val, Info, E)) | |||
2265 | return false; | |||
2266 | return HandleConversionToBool(Val, Result); | |||
2267 | } | |||
2268 | ||||
2269 | template<typename T> | |||
2270 | static bool HandleOverflow(EvalInfo &Info, const Expr *E, | |||
2271 | const T &SrcValue, QualType DestType) { | |||
2272 | Info.CCEDiag(E, diag::note_constexpr_overflow) | |||
2273 | << SrcValue << DestType; | |||
2274 | return Info.noteUndefinedBehavior(); | |||
2275 | } | |||
2276 | ||||
2277 | static bool HandleFloatToIntCast(EvalInfo &Info, const Expr *E, | |||
2278 | QualType SrcType, const APFloat &Value, | |||
2279 | QualType DestType, APSInt &Result) { | |||
2280 | unsigned DestWidth = Info.Ctx.getIntWidth(DestType); | |||
2281 | // Determine whether we are converting to unsigned or signed. | |||
2282 | bool DestSigned = DestType->isSignedIntegerOrEnumerationType(); | |||
2283 | ||||
2284 | Result = APSInt(DestWidth, !DestSigned); | |||
2285 | bool ignored; | |||
2286 | if (Value.convertToInteger(Result, llvm::APFloat::rmTowardZero, &ignored) | |||
2287 | & APFloat::opInvalidOp) | |||
2288 | return HandleOverflow(Info, E, Value, DestType); | |||
2289 | return true; | |||
2290 | } | |||
2291 | ||||
2292 | static bool HandleFloatToFloatCast(EvalInfo &Info, const Expr *E, | |||
2293 | QualType SrcType, QualType DestType, | |||
2294 | APFloat &Result) { | |||
2295 | APFloat Value = Result; | |||
2296 | bool ignored; | |||
2297 | Result.convert(Info.Ctx.getFloatTypeSemantics(DestType), | |||
2298 | APFloat::rmNearestTiesToEven, &ignored); | |||
2299 | return true; | |||
2300 | } | |||
2301 | ||||
2302 | static APSInt HandleIntToIntCast(EvalInfo &Info, const Expr *E, | |||
2303 | QualType DestType, QualType SrcType, | |||
2304 | const APSInt &Value) { | |||
2305 | unsigned DestWidth = Info.Ctx.getIntWidth(DestType); | |||
2306 | // Figure out if this is a truncate, extend or noop cast. | |||
2307 | // If the input is signed, do a sign extend, noop, or truncate. | |||
2308 | APSInt Result = Value.extOrTrunc(DestWidth); | |||
2309 | Result.setIsUnsigned(DestType->isUnsignedIntegerOrEnumerationType()); | |||
2310 | if (DestType->isBooleanType()) | |||
2311 | Result = Value.getBoolValue(); | |||
2312 | return Result; | |||
2313 | } | |||
2314 | ||||
2315 | static bool HandleIntToFloatCast(EvalInfo &Info, const Expr *E, | |||
2316 | QualType SrcType, const APSInt &Value, | |||
2317 | QualType DestType, APFloat &Result) { | |||
2318 | Result = APFloat(Info.Ctx.getFloatTypeSemantics(DestType), 1); | |||
2319 | Result.convertFromAPInt(Value, Value.isSigned(), | |||
2320 | APFloat::rmNearestTiesToEven); | |||
2321 | return true; | |||
2322 | } | |||
2323 | ||||
2324 | static bool truncateBitfieldValue(EvalInfo &Info, const Expr *E, | |||
2325 | APValue &Value, const FieldDecl *FD) { | |||
2326 | assert(FD->isBitField() && "truncateBitfieldValue on non-bitfield")((FD->isBitField() && "truncateBitfieldValue on non-bitfield" ) ? static_cast<void> (0) : __assert_fail ("FD->isBitField() && \"truncateBitfieldValue on non-bitfield\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2326, __PRETTY_FUNCTION__)); | |||
2327 | ||||
2328 | if (!Value.isInt()) { | |||
2329 | // Trying to store a pointer-cast-to-integer into a bitfield. | |||
2330 | // FIXME: In this case, we should provide the diagnostic for casting | |||
2331 | // a pointer to an integer. | |||
2332 | assert(Value.isLValue() && "integral value neither int nor lvalue?")((Value.isLValue() && "integral value neither int nor lvalue?" ) ? static_cast<void> (0) : __assert_fail ("Value.isLValue() && \"integral value neither int nor lvalue?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2332, __PRETTY_FUNCTION__)); | |||
2333 | Info.FFDiag(E); | |||
2334 | return false; | |||
2335 | } | |||
2336 | ||||
2337 | APSInt &Int = Value.getInt(); | |||
2338 | unsigned OldBitWidth = Int.getBitWidth(); | |||
2339 | unsigned NewBitWidth = FD->getBitWidthValue(Info.Ctx); | |||
2340 | if (NewBitWidth < OldBitWidth) | |||
2341 | Int = Int.trunc(NewBitWidth).extend(OldBitWidth); | |||
2342 | return true; | |||
2343 | } | |||
2344 | ||||
2345 | static bool EvalAndBitcastToAPInt(EvalInfo &Info, const Expr *E, | |||
2346 | llvm::APInt &Res) { | |||
2347 | APValue SVal; | |||
2348 | if (!Evaluate(SVal, Info, E)) | |||
2349 | return false; | |||
2350 | if (SVal.isInt()) { | |||
2351 | Res = SVal.getInt(); | |||
2352 | return true; | |||
2353 | } | |||
2354 | if (SVal.isFloat()) { | |||
2355 | Res = SVal.getFloat().bitcastToAPInt(); | |||
2356 | return true; | |||
2357 | } | |||
2358 | if (SVal.isVector()) { | |||
2359 | QualType VecTy = E->getType(); | |||
2360 | unsigned VecSize = Info.Ctx.getTypeSize(VecTy); | |||
2361 | QualType EltTy = VecTy->castAs<VectorType>()->getElementType(); | |||
2362 | unsigned EltSize = Info.Ctx.getTypeSize(EltTy); | |||
2363 | bool BigEndian = Info.Ctx.getTargetInfo().isBigEndian(); | |||
2364 | Res = llvm::APInt::getNullValue(VecSize); | |||
2365 | for (unsigned i = 0; i < SVal.getVectorLength(); i++) { | |||
2366 | APValue &Elt = SVal.getVectorElt(i); | |||
2367 | llvm::APInt EltAsInt; | |||
2368 | if (Elt.isInt()) { | |||
2369 | EltAsInt = Elt.getInt(); | |||
2370 | } else if (Elt.isFloat()) { | |||
2371 | EltAsInt = Elt.getFloat().bitcastToAPInt(); | |||
2372 | } else { | |||
2373 | // Don't try to handle vectors of anything other than int or float | |||
2374 | // (not sure if it's possible to hit this case). | |||
2375 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
2376 | return false; | |||
2377 | } | |||
2378 | unsigned BaseEltSize = EltAsInt.getBitWidth(); | |||
2379 | if (BigEndian) | |||
2380 | Res |= EltAsInt.zextOrTrunc(VecSize).rotr(i*EltSize+BaseEltSize); | |||
2381 | else | |||
2382 | Res |= EltAsInt.zextOrTrunc(VecSize).rotl(i*EltSize); | |||
2383 | } | |||
2384 | return true; | |||
2385 | } | |||
2386 | // Give up if the input isn't an int, float, or vector. For example, we | |||
2387 | // reject "(v4i16)(intptr_t)&a". | |||
2388 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
2389 | return false; | |||
2390 | } | |||
2391 | ||||
2392 | /// Perform the given integer operation, which is known to need at most BitWidth | |||
2393 | /// bits, and check for overflow in the original type (if that type was not an | |||
2394 | /// unsigned type). | |||
2395 | template<typename Operation> | |||
2396 | static bool CheckedIntArithmetic(EvalInfo &Info, const Expr *E, | |||
2397 | const APSInt &LHS, const APSInt &RHS, | |||
2398 | unsigned BitWidth, Operation Op, | |||
2399 | APSInt &Result) { | |||
2400 | if (LHS.isUnsigned()) { | |||
2401 | Result = Op(LHS, RHS); | |||
2402 | return true; | |||
2403 | } | |||
2404 | ||||
2405 | APSInt Value(Op(LHS.extend(BitWidth), RHS.extend(BitWidth)), false); | |||
2406 | Result = Value.trunc(LHS.getBitWidth()); | |||
2407 | if (Result.extend(BitWidth) != Value) { | |||
2408 | if (Info.checkingForUndefinedBehavior()) | |||
2409 | Info.Ctx.getDiagnostics().Report(E->getExprLoc(), | |||
2410 | diag::warn_integer_constant_overflow) | |||
2411 | << Result.toString(10) << E->getType(); | |||
2412 | else | |||
2413 | return HandleOverflow(Info, E, Value, E->getType()); | |||
2414 | } | |||
2415 | return true; | |||
2416 | } | |||
2417 | ||||
2418 | /// Perform the given binary integer operation. | |||
2419 | static bool handleIntIntBinOp(EvalInfo &Info, const Expr *E, const APSInt &LHS, | |||
2420 | BinaryOperatorKind Opcode, APSInt RHS, | |||
2421 | APSInt &Result) { | |||
2422 | switch (Opcode) { | |||
2423 | default: | |||
2424 | Info.FFDiag(E); | |||
2425 | return false; | |||
2426 | case BO_Mul: | |||
2427 | return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() * 2, | |||
2428 | std::multiplies<APSInt>(), Result); | |||
2429 | case BO_Add: | |||
2430 | return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() + 1, | |||
2431 | std::plus<APSInt>(), Result); | |||
2432 | case BO_Sub: | |||
2433 | return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() + 1, | |||
2434 | std::minus<APSInt>(), Result); | |||
2435 | case BO_And: Result = LHS & RHS; return true; | |||
2436 | case BO_Xor: Result = LHS ^ RHS; return true; | |||
2437 | case BO_Or: Result = LHS | RHS; return true; | |||
2438 | case BO_Div: | |||
2439 | case BO_Rem: | |||
2440 | if (RHS == 0) { | |||
2441 | Info.FFDiag(E, diag::note_expr_divide_by_zero); | |||
2442 | return false; | |||
2443 | } | |||
2444 | Result = (Opcode == BO_Rem ? LHS % RHS : LHS / RHS); | |||
2445 | // Check for overflow case: INT_MIN / -1 or INT_MIN % -1. APSInt supports | |||
2446 | // this operation and gives the two's complement result. | |||
2447 | if (RHS.isNegative() && RHS.isAllOnesValue() && | |||
2448 | LHS.isSigned() && LHS.isMinSignedValue()) | |||
2449 | return HandleOverflow(Info, E, -LHS.extend(LHS.getBitWidth() + 1), | |||
2450 | E->getType()); | |||
2451 | return true; | |||
2452 | case BO_Shl: { | |||
2453 | if (Info.getLangOpts().OpenCL) | |||
2454 | // OpenCL 6.3j: shift values are effectively % word size of LHS. | |||
2455 | RHS &= APSInt(llvm::APInt(RHS.getBitWidth(), | |||
2456 | static_cast<uint64_t>(LHS.getBitWidth() - 1)), | |||
2457 | RHS.isUnsigned()); | |||
2458 | else if (RHS.isSigned() && RHS.isNegative()) { | |||
2459 | // During constant-folding, a negative shift is an opposite shift. Such | |||
2460 | // a shift is not a constant expression. | |||
2461 | Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHS; | |||
2462 | RHS = -RHS; | |||
2463 | goto shift_right; | |||
2464 | } | |||
2465 | shift_left: | |||
2466 | // C++11 [expr.shift]p1: Shift width must be less than the bit width of | |||
2467 | // the shifted type. | |||
2468 | unsigned SA = (unsigned) RHS.getLimitedValue(LHS.getBitWidth()-1); | |||
2469 | if (SA != RHS) { | |||
2470 | Info.CCEDiag(E, diag::note_constexpr_large_shift) | |||
2471 | << RHS << E->getType() << LHS.getBitWidth(); | |||
2472 | } else if (LHS.isSigned() && !Info.getLangOpts().CPlusPlus2a) { | |||
2473 | // C++11 [expr.shift]p2: A signed left shift must have a non-negative | |||
2474 | // operand, and must not overflow the corresponding unsigned type. | |||
2475 | // C++2a [expr.shift]p2: E1 << E2 is the unique value congruent to | |||
2476 | // E1 x 2^E2 module 2^N. | |||
2477 | if (LHS.isNegative()) | |||
2478 | Info.CCEDiag(E, diag::note_constexpr_lshift_of_negative) << LHS; | |||
2479 | else if (LHS.countLeadingZeros() < SA) | |||
2480 | Info.CCEDiag(E, diag::note_constexpr_lshift_discards); | |||
2481 | } | |||
2482 | Result = LHS << SA; | |||
2483 | return true; | |||
2484 | } | |||
2485 | case BO_Shr: { | |||
2486 | if (Info.getLangOpts().OpenCL) | |||
2487 | // OpenCL 6.3j: shift values are effectively % word size of LHS. | |||
2488 | RHS &= APSInt(llvm::APInt(RHS.getBitWidth(), | |||
2489 | static_cast<uint64_t>(LHS.getBitWidth() - 1)), | |||
2490 | RHS.isUnsigned()); | |||
2491 | else if (RHS.isSigned() && RHS.isNegative()) { | |||
2492 | // During constant-folding, a negative shift is an opposite shift. Such a | |||
2493 | // shift is not a constant expression. | |||
2494 | Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHS; | |||
2495 | RHS = -RHS; | |||
2496 | goto shift_left; | |||
2497 | } | |||
2498 | shift_right: | |||
2499 | // C++11 [expr.shift]p1: Shift width must be less than the bit width of the | |||
2500 | // shifted type. | |||
2501 | unsigned SA = (unsigned) RHS.getLimitedValue(LHS.getBitWidth()-1); | |||
2502 | if (SA != RHS) | |||
2503 | Info.CCEDiag(E, diag::note_constexpr_large_shift) | |||
2504 | << RHS << E->getType() << LHS.getBitWidth(); | |||
2505 | Result = LHS >> SA; | |||
2506 | return true; | |||
2507 | } | |||
2508 | ||||
2509 | case BO_LT: Result = LHS < RHS; return true; | |||
2510 | case BO_GT: Result = LHS > RHS; return true; | |||
2511 | case BO_LE: Result = LHS <= RHS; return true; | |||
2512 | case BO_GE: Result = LHS >= RHS; return true; | |||
2513 | case BO_EQ: Result = LHS == RHS; return true; | |||
2514 | case BO_NE: Result = LHS != RHS; return true; | |||
2515 | case BO_Cmp: | |||
2516 | llvm_unreachable("BO_Cmp should be handled elsewhere")::llvm::llvm_unreachable_internal("BO_Cmp should be handled elsewhere" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2516); | |||
2517 | } | |||
2518 | } | |||
2519 | ||||
2520 | /// Perform the given binary floating-point operation, in-place, on LHS. | |||
2521 | static bool handleFloatFloatBinOp(EvalInfo &Info, const Expr *E, | |||
2522 | APFloat &LHS, BinaryOperatorKind Opcode, | |||
2523 | const APFloat &RHS) { | |||
2524 | switch (Opcode) { | |||
2525 | default: | |||
2526 | Info.FFDiag(E); | |||
2527 | return false; | |||
2528 | case BO_Mul: | |||
2529 | LHS.multiply(RHS, APFloat::rmNearestTiesToEven); | |||
2530 | break; | |||
2531 | case BO_Add: | |||
2532 | LHS.add(RHS, APFloat::rmNearestTiesToEven); | |||
2533 | break; | |||
2534 | case BO_Sub: | |||
2535 | LHS.subtract(RHS, APFloat::rmNearestTiesToEven); | |||
2536 | break; | |||
2537 | case BO_Div: | |||
2538 | // [expr.mul]p4: | |||
2539 | // If the second operand of / or % is zero the behavior is undefined. | |||
2540 | if (RHS.isZero()) | |||
2541 | Info.CCEDiag(E, diag::note_expr_divide_by_zero); | |||
2542 | LHS.divide(RHS, APFloat::rmNearestTiesToEven); | |||
2543 | break; | |||
2544 | } | |||
2545 | ||||
2546 | // [expr.pre]p4: | |||
2547 | // If during the evaluation of an expression, the result is not | |||
2548 | // mathematically defined [...], the behavior is undefined. | |||
2549 | // FIXME: C++ rules require us to not conform to IEEE 754 here. | |||
2550 | if (LHS.isNaN()) { | |||
2551 | Info.CCEDiag(E, diag::note_constexpr_float_arithmetic) << LHS.isNaN(); | |||
2552 | return Info.noteUndefinedBehavior(); | |||
2553 | } | |||
2554 | return true; | |||
2555 | } | |||
2556 | ||||
2557 | /// Cast an lvalue referring to a base subobject to a derived class, by | |||
2558 | /// truncating the lvalue's path to the given length. | |||
2559 | static bool CastToDerivedClass(EvalInfo &Info, const Expr *E, LValue &Result, | |||
2560 | const RecordDecl *TruncatedType, | |||
2561 | unsigned TruncatedElements) { | |||
2562 | SubobjectDesignator &D = Result.Designator; | |||
2563 | ||||
2564 | // Check we actually point to a derived class object. | |||
2565 | if (TruncatedElements == D.Entries.size()) | |||
2566 | return true; | |||
2567 | assert(TruncatedElements >= D.MostDerivedPathLength &&((TruncatedElements >= D.MostDerivedPathLength && "not casting to a derived class" ) ? static_cast<void> (0) : __assert_fail ("TruncatedElements >= D.MostDerivedPathLength && \"not casting to a derived class\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2568, __PRETTY_FUNCTION__)) | |||
2568 | "not casting to a derived class")((TruncatedElements >= D.MostDerivedPathLength && "not casting to a derived class" ) ? static_cast<void> (0) : __assert_fail ("TruncatedElements >= D.MostDerivedPathLength && \"not casting to a derived class\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2568, __PRETTY_FUNCTION__)); | |||
2569 | if (!Result.checkSubobject(Info, E, CSK_Derived)) | |||
2570 | return false; | |||
2571 | ||||
2572 | // Truncate the path to the subobject, and remove any derived-to-base offsets. | |||
2573 | const RecordDecl *RD = TruncatedType; | |||
2574 | for (unsigned I = TruncatedElements, N = D.Entries.size(); I != N; ++I) { | |||
2575 | if (RD->isInvalidDecl()) return false; | |||
2576 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
2577 | const CXXRecordDecl *Base = getAsBaseClass(D.Entries[I]); | |||
2578 | if (isVirtualBaseClass(D.Entries[I])) | |||
2579 | Result.Offset -= Layout.getVBaseClassOffset(Base); | |||
2580 | else | |||
2581 | Result.Offset -= Layout.getBaseClassOffset(Base); | |||
2582 | RD = Base; | |||
2583 | } | |||
2584 | D.Entries.resize(TruncatedElements); | |||
2585 | return true; | |||
2586 | } | |||
2587 | ||||
2588 | static bool HandleLValueDirectBase(EvalInfo &Info, const Expr *E, LValue &Obj, | |||
2589 | const CXXRecordDecl *Derived, | |||
2590 | const CXXRecordDecl *Base, | |||
2591 | const ASTRecordLayout *RL = nullptr) { | |||
2592 | if (!RL) { | |||
2593 | if (Derived->isInvalidDecl()) return false; | |||
2594 | RL = &Info.Ctx.getASTRecordLayout(Derived); | |||
2595 | } | |||
2596 | ||||
2597 | Obj.getLValueOffset() += RL->getBaseClassOffset(Base); | |||
2598 | Obj.addDecl(Info, E, Base, /*Virtual*/ false); | |||
2599 | return true; | |||
2600 | } | |||
2601 | ||||
2602 | static bool HandleLValueBase(EvalInfo &Info, const Expr *E, LValue &Obj, | |||
2603 | const CXXRecordDecl *DerivedDecl, | |||
2604 | const CXXBaseSpecifier *Base) { | |||
2605 | const CXXRecordDecl *BaseDecl = Base->getType()->getAsCXXRecordDecl(); | |||
2606 | ||||
2607 | if (!Base->isVirtual()) | |||
2608 | return HandleLValueDirectBase(Info, E, Obj, DerivedDecl, BaseDecl); | |||
2609 | ||||
2610 | SubobjectDesignator &D = Obj.Designator; | |||
2611 | if (D.Invalid) | |||
2612 | return false; | |||
2613 | ||||
2614 | // Extract most-derived object and corresponding type. | |||
2615 | DerivedDecl = D.MostDerivedType->getAsCXXRecordDecl(); | |||
2616 | if (!CastToDerivedClass(Info, E, Obj, DerivedDecl, D.MostDerivedPathLength)) | |||
2617 | return false; | |||
2618 | ||||
2619 | // Find the virtual base class. | |||
2620 | if (DerivedDecl->isInvalidDecl()) return false; | |||
2621 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(DerivedDecl); | |||
2622 | Obj.getLValueOffset() += Layout.getVBaseClassOffset(BaseDecl); | |||
2623 | Obj.addDecl(Info, E, BaseDecl, /*Virtual*/ true); | |||
2624 | return true; | |||
2625 | } | |||
2626 | ||||
2627 | static bool HandleLValueBasePath(EvalInfo &Info, const CastExpr *E, | |||
2628 | QualType Type, LValue &Result) { | |||
2629 | for (CastExpr::path_const_iterator PathI = E->path_begin(), | |||
2630 | PathE = E->path_end(); | |||
2631 | PathI != PathE; ++PathI) { | |||
2632 | if (!HandleLValueBase(Info, E, Result, Type->getAsCXXRecordDecl(), | |||
2633 | *PathI)) | |||
2634 | return false; | |||
2635 | Type = (*PathI)->getType(); | |||
2636 | } | |||
2637 | return true; | |||
2638 | } | |||
2639 | ||||
2640 | /// Cast an lvalue referring to a derived class to a known base subobject. | |||
2641 | static bool CastToBaseClass(EvalInfo &Info, const Expr *E, LValue &Result, | |||
2642 | const CXXRecordDecl *DerivedRD, | |||
2643 | const CXXRecordDecl *BaseRD) { | |||
2644 | CXXBasePaths Paths(/*FindAmbiguities=*/false, | |||
2645 | /*RecordPaths=*/true, /*DetectVirtual=*/false); | |||
2646 | if (!DerivedRD->isDerivedFrom(BaseRD, Paths)) | |||
2647 | 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!" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2647); | |||
2648 | ||||
2649 | for (CXXBasePathElement &Elem : Paths.front()) | |||
2650 | if (!HandleLValueBase(Info, E, Result, Elem.Class, Elem.Base)) | |||
2651 | return false; | |||
2652 | return true; | |||
2653 | } | |||
2654 | ||||
2655 | /// Update LVal to refer to the given field, which must be a member of the type | |||
2656 | /// currently described by LVal. | |||
2657 | static bool HandleLValueMember(EvalInfo &Info, const Expr *E, LValue &LVal, | |||
2658 | const FieldDecl *FD, | |||
2659 | const ASTRecordLayout *RL = nullptr) { | |||
2660 | if (!RL) { | |||
2661 | if (FD->getParent()->isInvalidDecl()) return false; | |||
2662 | RL = &Info.Ctx.getASTRecordLayout(FD->getParent()); | |||
2663 | } | |||
2664 | ||||
2665 | unsigned I = FD->getFieldIndex(); | |||
2666 | LVal.adjustOffset(Info.Ctx.toCharUnitsFromBits(RL->getFieldOffset(I))); | |||
2667 | LVal.addDecl(Info, E, FD); | |||
2668 | return true; | |||
2669 | } | |||
2670 | ||||
2671 | /// Update LVal to refer to the given indirect field. | |||
2672 | static bool HandleLValueIndirectMember(EvalInfo &Info, const Expr *E, | |||
2673 | LValue &LVal, | |||
2674 | const IndirectFieldDecl *IFD) { | |||
2675 | for (const auto *C : IFD->chain()) | |||
2676 | if (!HandleLValueMember(Info, E, LVal, cast<FieldDecl>(C))) | |||
2677 | return false; | |||
2678 | return true; | |||
2679 | } | |||
2680 | ||||
2681 | /// Get the size of the given type in char units. | |||
2682 | static bool HandleSizeof(EvalInfo &Info, SourceLocation Loc, | |||
2683 | QualType Type, CharUnits &Size) { | |||
2684 | // sizeof(void), __alignof__(void), sizeof(function) = 1 as a gcc | |||
2685 | // extension. | |||
2686 | if (Type->isVoidType() || Type->isFunctionType()) { | |||
2687 | Size = CharUnits::One(); | |||
2688 | return true; | |||
2689 | } | |||
2690 | ||||
2691 | if (Type->isDependentType()) { | |||
2692 | Info.FFDiag(Loc); | |||
2693 | return false; | |||
2694 | } | |||
2695 | ||||
2696 | if (!Type->isConstantSizeType()) { | |||
2697 | // sizeof(vla) is not a constantexpr: C99 6.5.3.4p2. | |||
2698 | // FIXME: Better diagnostic. | |||
2699 | Info.FFDiag(Loc); | |||
2700 | return false; | |||
2701 | } | |||
2702 | ||||
2703 | Size = Info.Ctx.getTypeSizeInChars(Type); | |||
2704 | return true; | |||
2705 | } | |||
2706 | ||||
2707 | /// Update a pointer value to model pointer arithmetic. | |||
2708 | /// \param Info - Information about the ongoing evaluation. | |||
2709 | /// \param E - The expression being evaluated, for diagnostic purposes. | |||
2710 | /// \param LVal - The pointer value to be updated. | |||
2711 | /// \param EltTy - The pointee type represented by LVal. | |||
2712 | /// \param Adjustment - The adjustment, in objects of type EltTy, to add. | |||
2713 | static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E, | |||
2714 | LValue &LVal, QualType EltTy, | |||
2715 | APSInt Adjustment) { | |||
2716 | CharUnits SizeOfPointee; | |||
2717 | if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfPointee)) | |||
2718 | return false; | |||
2719 | ||||
2720 | LVal.adjustOffsetAndIndex(Info, E, Adjustment, SizeOfPointee); | |||
2721 | return true; | |||
2722 | } | |||
2723 | ||||
2724 | static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E, | |||
2725 | LValue &LVal, QualType EltTy, | |||
2726 | int64_t Adjustment) { | |||
2727 | return HandleLValueArrayAdjustment(Info, E, LVal, EltTy, | |||
2728 | APSInt::get(Adjustment)); | |||
2729 | } | |||
2730 | ||||
2731 | /// Update an lvalue to refer to a component of a complex number. | |||
2732 | /// \param Info - Information about the ongoing evaluation. | |||
2733 | /// \param LVal - The lvalue to be updated. | |||
2734 | /// \param EltTy - The complex number's component type. | |||
2735 | /// \param Imag - False for the real component, true for the imaginary. | |||
2736 | static bool HandleLValueComplexElement(EvalInfo &Info, const Expr *E, | |||
2737 | LValue &LVal, QualType EltTy, | |||
2738 | bool Imag) { | |||
2739 | if (Imag) { | |||
2740 | CharUnits SizeOfComponent; | |||
2741 | if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfComponent)) | |||
2742 | return false; | |||
2743 | LVal.Offset += SizeOfComponent; | |||
2744 | } | |||
2745 | LVal.addComplex(Info, E, EltTy, Imag); | |||
2746 | return true; | |||
2747 | } | |||
2748 | ||||
2749 | /// Try to evaluate the initializer for a variable declaration. | |||
2750 | /// | |||
2751 | /// \param Info Information about the ongoing evaluation. | |||
2752 | /// \param E An expression to be used when printing diagnostics. | |||
2753 | /// \param VD The variable whose initializer should be obtained. | |||
2754 | /// \param Frame The frame in which the variable was created. Must be null | |||
2755 | /// if this variable is not local to the evaluation. | |||
2756 | /// \param Result Filled in with a pointer to the value of the variable. | |||
2757 | static bool evaluateVarDeclInit(EvalInfo &Info, const Expr *E, | |||
2758 | const VarDecl *VD, CallStackFrame *Frame, | |||
2759 | APValue *&Result, const LValue *LVal) { | |||
2760 | ||||
2761 | // If this is a parameter to an active constexpr function call, perform | |||
2762 | // argument substitution. | |||
2763 | if (const ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(VD)) { | |||
2764 | // Assume arguments of a potential constant expression are unknown | |||
2765 | // constant expressions. | |||
2766 | if (Info.checkingPotentialConstantExpression()) | |||
2767 | return false; | |||
2768 | if (!Frame || !Frame->Arguments) { | |||
2769 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
2770 | return false; | |||
2771 | } | |||
2772 | Result = &Frame->Arguments[PVD->getFunctionScopeIndex()]; | |||
2773 | return true; | |||
2774 | } | |||
2775 | ||||
2776 | // If this is a local variable, dig out its value. | |||
2777 | if (Frame) { | |||
2778 | Result = LVal ? Frame->getTemporary(VD, LVal->getLValueVersion()) | |||
2779 | : Frame->getCurrentTemporary(VD); | |||
2780 | if (!Result) { | |||
2781 | // Assume variables referenced within a lambda's call operator that were | |||
2782 | // not declared within the call operator are captures and during checking | |||
2783 | // of a potential constant expression, assume they are unknown constant | |||
2784 | // expressions. | |||
2785 | assert(isLambdaCallOperator(Frame->Callee) &&((isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext () != Frame->Callee || VD->isInitCapture()) && "missing value for local variable" ) ? static_cast<void> (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2787, __PRETTY_FUNCTION__)) | |||
2786 | (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) &&((isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext () != Frame->Callee || VD->isInitCapture()) && "missing value for local variable" ) ? static_cast<void> (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2787, __PRETTY_FUNCTION__)) | |||
2787 | "missing value for local variable")((isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext () != Frame->Callee || VD->isInitCapture()) && "missing value for local variable" ) ? static_cast<void> (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2787, __PRETTY_FUNCTION__)); | |||
2788 | if (Info.checkingPotentialConstantExpression()) | |||
2789 | return false; | |||
2790 | // FIXME: implement capture evaluation during constant expr evaluation. | |||
2791 | Info.FFDiag(E->getBeginLoc(), | |||
2792 | diag::note_unimplemented_constexpr_lambda_feature_ast) | |||
2793 | << "captures not currently allowed"; | |||
2794 | return false; | |||
2795 | } | |||
2796 | return true; | |||
2797 | } | |||
2798 | ||||
2799 | // Dig out the initializer, and use the declaration which it's attached to. | |||
2800 | const Expr *Init = VD->getAnyInitializer(VD); | |||
2801 | if (!Init || Init->isValueDependent()) { | |||
2802 | // If we're checking a potential constant expression, the variable could be | |||
2803 | // initialized later. | |||
2804 | if (!Info.checkingPotentialConstantExpression()) | |||
2805 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
2806 | return false; | |||
2807 | } | |||
2808 | ||||
2809 | // If we're currently evaluating the initializer of this declaration, use that | |||
2810 | // in-flight value. | |||
2811 | if (Info.EvaluatingDecl.dyn_cast<const ValueDecl*>() == VD) { | |||
2812 | Result = Info.EvaluatingDeclValue; | |||
2813 | return true; | |||
2814 | } | |||
2815 | ||||
2816 | // Never evaluate the initializer of a weak variable. We can't be sure that | |||
2817 | // this is the definition which will be used. | |||
2818 | if (VD->isWeak()) { | |||
2819 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
2820 | return false; | |||
2821 | } | |||
2822 | ||||
2823 | // Check that we can fold the initializer. In C++, we will have already done | |||
2824 | // this in the cases where it matters for conformance. | |||
2825 | SmallVector<PartialDiagnosticAt, 8> Notes; | |||
2826 | if (!VD->evaluateValue(Notes)) { | |||
2827 | Info.FFDiag(E, diag::note_constexpr_var_init_non_constant, | |||
2828 | Notes.size() + 1) << VD; | |||
2829 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
2830 | Info.addNotes(Notes); | |||
2831 | return false; | |||
2832 | } else if (!VD->checkInitIsICE()) { | |||
2833 | Info.CCEDiag(E, diag::note_constexpr_var_init_non_constant, | |||
2834 | Notes.size() + 1) << VD; | |||
2835 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
2836 | Info.addNotes(Notes); | |||
2837 | } | |||
2838 | ||||
2839 | Result = VD->getEvaluatedValue(); | |||
2840 | return true; | |||
2841 | } | |||
2842 | ||||
2843 | static bool IsConstNonVolatile(QualType T) { | |||
2844 | Qualifiers Quals = T.getQualifiers(); | |||
2845 | return Quals.hasConst() && !Quals.hasVolatile(); | |||
2846 | } | |||
2847 | ||||
2848 | /// Get the base index of the given base class within an APValue representing | |||
2849 | /// the given derived class. | |||
2850 | static unsigned getBaseIndex(const CXXRecordDecl *Derived, | |||
2851 | const CXXRecordDecl *Base) { | |||
2852 | Base = Base->getCanonicalDecl(); | |||
2853 | unsigned Index = 0; | |||
2854 | for (CXXRecordDecl::base_class_const_iterator I = Derived->bases_begin(), | |||
2855 | E = Derived->bases_end(); I != E; ++I, ++Index) { | |||
2856 | if (I->getType()->getAsCXXRecordDecl()->getCanonicalDecl() == Base) | |||
2857 | return Index; | |||
2858 | } | |||
2859 | ||||
2860 | llvm_unreachable("base class missing from derived class's bases list")::llvm::llvm_unreachable_internal("base class missing from derived class's bases list" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2860); | |||
2861 | } | |||
2862 | ||||
2863 | /// Extract the value of a character from a string literal. | |||
2864 | static APSInt extractStringLiteralCharacter(EvalInfo &Info, const Expr *Lit, | |||
2865 | uint64_t Index) { | |||
2866 | assert(!isa<SourceLocExpr>(Lit) &&((!isa<SourceLocExpr>(Lit) && "SourceLocExpr should have already been converted to a StringLiteral" ) ? static_cast<void> (0) : __assert_fail ("!isa<SourceLocExpr>(Lit) && \"SourceLocExpr should have already been converted to a StringLiteral\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2867, __PRETTY_FUNCTION__)) | |||
2867 | "SourceLocExpr should have already been converted to a StringLiteral")((!isa<SourceLocExpr>(Lit) && "SourceLocExpr should have already been converted to a StringLiteral" ) ? static_cast<void> (0) : __assert_fail ("!isa<SourceLocExpr>(Lit) && \"SourceLocExpr should have already been converted to a StringLiteral\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2867, __PRETTY_FUNCTION__)); | |||
2868 | ||||
2869 | // FIXME: Support MakeStringConstant | |||
2870 | if (const auto *ObjCEnc = dyn_cast<ObjCEncodeExpr>(Lit)) { | |||
2871 | std::string Str; | |||
2872 | Info.Ctx.getObjCEncodingForType(ObjCEnc->getEncodedType(), Str); | |||
2873 | assert(Index <= Str.size() && "Index too large")((Index <= Str.size() && "Index too large") ? static_cast <void> (0) : __assert_fail ("Index <= Str.size() && \"Index too large\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2873, __PRETTY_FUNCTION__)); | |||
2874 | return APSInt::getUnsigned(Str.c_str()[Index]); | |||
2875 | } | |||
2876 | ||||
2877 | if (auto PE = dyn_cast<PredefinedExpr>(Lit)) | |||
2878 | Lit = PE->getFunctionName(); | |||
2879 | const StringLiteral *S = cast<StringLiteral>(Lit); | |||
2880 | const ConstantArrayType *CAT = | |||
2881 | Info.Ctx.getAsConstantArrayType(S->getType()); | |||
2882 | assert(CAT && "string literal isn't an array")((CAT && "string literal isn't an array") ? static_cast <void> (0) : __assert_fail ("CAT && \"string literal isn't an array\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2882, __PRETTY_FUNCTION__)); | |||
2883 | QualType CharType = CAT->getElementType(); | |||
2884 | assert(CharType->isIntegerType() && "unexpected character type")((CharType->isIntegerType() && "unexpected character type" ) ? static_cast<void> (0) : __assert_fail ("CharType->isIntegerType() && \"unexpected character type\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2884, __PRETTY_FUNCTION__)); | |||
2885 | ||||
2886 | APSInt Value(S->getCharByteWidth() * Info.Ctx.getCharWidth(), | |||
2887 | CharType->isUnsignedIntegerType()); | |||
2888 | if (Index < S->getLength()) | |||
2889 | Value = S->getCodeUnit(Index); | |||
2890 | return Value; | |||
2891 | } | |||
2892 | ||||
2893 | // Expand a string literal into an array of characters. | |||
2894 | // | |||
2895 | // FIXME: This is inefficient; we should probably introduce something similar | |||
2896 | // to the LLVM ConstantDataArray to make this cheaper. | |||
2897 | static void expandStringLiteral(EvalInfo &Info, const StringLiteral *S, | |||
2898 | APValue &Result, | |||
2899 | QualType AllocType = QualType()) { | |||
2900 | const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType( | |||
2901 | AllocType.isNull() ? S->getType() : AllocType); | |||
2902 | assert(CAT && "string literal isn't an array")((CAT && "string literal isn't an array") ? static_cast <void> (0) : __assert_fail ("CAT && \"string literal isn't an array\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2902, __PRETTY_FUNCTION__)); | |||
2903 | QualType CharType = CAT->getElementType(); | |||
2904 | assert(CharType->isIntegerType() && "unexpected character type")((CharType->isIntegerType() && "unexpected character type" ) ? static_cast<void> (0) : __assert_fail ("CharType->isIntegerType() && \"unexpected character type\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2904, __PRETTY_FUNCTION__)); | |||
2905 | ||||
2906 | unsigned Elts = CAT->getSize().getZExtValue(); | |||
2907 | Result = APValue(APValue::UninitArray(), | |||
2908 | std::min(S->getLength(), Elts), Elts); | |||
2909 | APSInt Value(S->getCharByteWidth() * Info.Ctx.getCharWidth(), | |||
2910 | CharType->isUnsignedIntegerType()); | |||
2911 | if (Result.hasArrayFiller()) | |||
2912 | Result.getArrayFiller() = APValue(Value); | |||
2913 | for (unsigned I = 0, N = Result.getArrayInitializedElts(); I != N; ++I) { | |||
2914 | Value = S->getCodeUnit(I); | |||
2915 | Result.getArrayInitializedElt(I) = APValue(Value); | |||
2916 | } | |||
2917 | } | |||
2918 | ||||
2919 | // Expand an array so that it has more than Index filled elements. | |||
2920 | static void expandArray(APValue &Array, unsigned Index) { | |||
2921 | unsigned Size = Array.getArraySize(); | |||
2922 | assert(Index < Size)((Index < Size) ? static_cast<void> (0) : __assert_fail ("Index < Size", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 2922, __PRETTY_FUNCTION__)); | |||
2923 | ||||
2924 | // Always at least double the number of elements for which we store a value. | |||
2925 | unsigned OldElts = Array.getArrayInitializedElts(); | |||
2926 | unsigned NewElts = std::max(Index+1, OldElts * 2); | |||
2927 | NewElts = std::min(Size, std::max(NewElts, 8u)); | |||
2928 | ||||
2929 | // Copy the data across. | |||
2930 | APValue NewValue(APValue::UninitArray(), NewElts, Size); | |||
2931 | for (unsigned I = 0; I != OldElts; ++I) | |||
2932 | NewValue.getArrayInitializedElt(I).swap(Array.getArrayInitializedElt(I)); | |||
2933 | for (unsigned I = OldElts; I != NewElts; ++I) | |||
2934 | NewValue.getArrayInitializedElt(I) = Array.getArrayFiller(); | |||
2935 | if (NewValue.hasArrayFiller()) | |||
2936 | NewValue.getArrayFiller() = Array.getArrayFiller(); | |||
2937 | Array.swap(NewValue); | |||
2938 | } | |||
2939 | ||||
2940 | /// Determine whether a type would actually be read by an lvalue-to-rvalue | |||
2941 | /// conversion. If it's of class type, we may assume that the copy operation | |||
2942 | /// is trivial. Note that this is never true for a union type with fields | |||
2943 | /// (because the copy always "reads" the active member) and always true for | |||
2944 | /// a non-class type. | |||
2945 | static bool isReadByLvalueToRvalueConversion(QualType T) { | |||
2946 | CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); | |||
2947 | if (!RD || (RD->isUnion() && !RD->field_empty())) | |||
2948 | return true; | |||
2949 | if (RD->isEmpty()) | |||
2950 | return false; | |||
2951 | ||||
2952 | for (auto *Field : RD->fields()) | |||
2953 | if (isReadByLvalueToRvalueConversion(Field->getType())) | |||
2954 | return true; | |||
2955 | ||||
2956 | for (auto &BaseSpec : RD->bases()) | |||
2957 | if (isReadByLvalueToRvalueConversion(BaseSpec.getType())) | |||
2958 | return true; | |||
2959 | ||||
2960 | return false; | |||
2961 | } | |||
2962 | ||||
2963 | /// Diagnose an attempt to read from any unreadable field within the specified | |||
2964 | /// type, which might be a class type. | |||
2965 | static bool diagnoseMutableFields(EvalInfo &Info, const Expr *E, AccessKinds AK, | |||
2966 | QualType T) { | |||
2967 | CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl(); | |||
2968 | if (!RD) | |||
2969 | return false; | |||
2970 | ||||
2971 | if (!RD->hasMutableFields()) | |||
2972 | return false; | |||
2973 | ||||
2974 | for (auto *Field : RD->fields()) { | |||
2975 | // If we're actually going to read this field in some way, then it can't | |||
2976 | // be mutable. If we're in a union, then assigning to a mutable field | |||
2977 | // (even an empty one) can change the active member, so that's not OK. | |||
2978 | // FIXME: Add core issue number for the union case. | |||
2979 | if (Field->isMutable() && | |||
2980 | (RD->isUnion() || isReadByLvalueToRvalueConversion(Field->getType()))) { | |||
2981 | Info.FFDiag(E, diag::note_constexpr_access_mutable, 1) << AK << Field; | |||
2982 | Info.Note(Field->getLocation(), diag::note_declared_at); | |||
2983 | return true; | |||
2984 | } | |||
2985 | ||||
2986 | if (diagnoseMutableFields(Info, E, AK, Field->getType())) | |||
2987 | return true; | |||
2988 | } | |||
2989 | ||||
2990 | for (auto &BaseSpec : RD->bases()) | |||
2991 | if (diagnoseMutableFields(Info, E, AK, BaseSpec.getType())) | |||
2992 | return true; | |||
2993 | ||||
2994 | // All mutable fields were empty, and thus not actually read. | |||
2995 | return false; | |||
2996 | } | |||
2997 | ||||
2998 | static bool lifetimeStartedInEvaluation(EvalInfo &Info, | |||
2999 | APValue::LValueBase Base, | |||
3000 | bool MutableSubobject = false) { | |||
3001 | // A temporary we created. | |||
3002 | if (Base.getCallIndex()) | |||
3003 | return true; | |||
3004 | ||||
3005 | auto *Evaluating = Info.EvaluatingDecl.dyn_cast<const ValueDecl*>(); | |||
3006 | if (!Evaluating) | |||
3007 | return false; | |||
3008 | ||||
3009 | auto *BaseD = Base.dyn_cast<const ValueDecl*>(); | |||
3010 | ||||
3011 | switch (Info.IsEvaluatingDecl) { | |||
3012 | case EvalInfo::EvaluatingDeclKind::None: | |||
3013 | return false; | |||
3014 | ||||
3015 | case EvalInfo::EvaluatingDeclKind::Ctor: | |||
3016 | // The variable whose initializer we're evaluating. | |||
3017 | if (BaseD) | |||
3018 | return declaresSameEntity(Evaluating, BaseD); | |||
3019 | ||||
3020 | // A temporary lifetime-extended by the variable whose initializer we're | |||
3021 | // evaluating. | |||
3022 | if (auto *BaseE = Base.dyn_cast<const Expr *>()) | |||
3023 | if (auto *BaseMTE = dyn_cast<MaterializeTemporaryExpr>(BaseE)) | |||
3024 | return declaresSameEntity(BaseMTE->getExtendingDecl(), Evaluating); | |||
3025 | return false; | |||
3026 | ||||
3027 | case EvalInfo::EvaluatingDeclKind::Dtor: | |||
3028 | // C++2a [expr.const]p6: | |||
3029 | // [during constant destruction] the lifetime of a and its non-mutable | |||
3030 | // subobjects (but not its mutable subobjects) [are] considered to start | |||
3031 | // within e. | |||
3032 | // | |||
3033 | // FIXME: We can meaningfully extend this to cover non-const objects, but | |||
3034 | // we will need special handling: we should be able to access only | |||
3035 | // subobjects of such objects that are themselves declared const. | |||
3036 | if (!BaseD || | |||
3037 | !(BaseD->getType().isConstQualified() || | |||
3038 | BaseD->getType()->isReferenceType()) || | |||
3039 | MutableSubobject) | |||
3040 | return false; | |||
3041 | return declaresSameEntity(Evaluating, BaseD); | |||
3042 | } | |||
3043 | ||||
3044 | llvm_unreachable("unknown evaluating decl kind")::llvm::llvm_unreachable_internal("unknown evaluating decl kind" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3044); | |||
3045 | } | |||
3046 | ||||
3047 | namespace { | |||
3048 | /// A handle to a complete object (an object that is not a subobject of | |||
3049 | /// another object). | |||
3050 | struct CompleteObject { | |||
3051 | /// The identity of the object. | |||
3052 | APValue::LValueBase Base; | |||
3053 | /// The value of the complete object. | |||
3054 | APValue *Value; | |||
3055 | /// The type of the complete object. | |||
3056 | QualType Type; | |||
3057 | ||||
3058 | CompleteObject() : Value(nullptr) {} | |||
3059 | CompleteObject(APValue::LValueBase Base, APValue *Value, QualType Type) | |||
3060 | : Base(Base), Value(Value), Type(Type) {} | |||
3061 | ||||
3062 | bool mayAccessMutableMembers(EvalInfo &Info, AccessKinds AK) const { | |||
3063 | // In C++14 onwards, it is permitted to read a mutable member whose | |||
3064 | // lifetime began within the evaluation. | |||
3065 | // FIXME: Should we also allow this in C++11? | |||
3066 | if (!Info.getLangOpts().CPlusPlus14) | |||
3067 | return false; | |||
3068 | return lifetimeStartedInEvaluation(Info, Base, /*MutableSubobject*/true); | |||
3069 | } | |||
3070 | ||||
3071 | explicit operator bool() const { return !Type.isNull(); } | |||
3072 | }; | |||
3073 | } // end anonymous namespace | |||
3074 | ||||
3075 | static QualType getSubobjectType(QualType ObjType, QualType SubobjType, | |||
3076 | bool IsMutable = false) { | |||
3077 | // C++ [basic.type.qualifier]p1: | |||
3078 | // - A const object is an object of type const T or a non-mutable subobject | |||
3079 | // of a const object. | |||
3080 | if (ObjType.isConstQualified() && !IsMutable) | |||
3081 | SubobjType.addConst(); | |||
3082 | // - A volatile object is an object of type const T or a subobject of a | |||
3083 | // volatile object. | |||
3084 | if (ObjType.isVolatileQualified()) | |||
3085 | SubobjType.addVolatile(); | |||
3086 | return SubobjType; | |||
3087 | } | |||
3088 | ||||
3089 | /// Find the designated sub-object of an rvalue. | |||
3090 | template<typename SubobjectHandler> | |||
3091 | typename SubobjectHandler::result_type | |||
3092 | findSubobject(EvalInfo &Info, const Expr *E, const CompleteObject &Obj, | |||
3093 | const SubobjectDesignator &Sub, SubobjectHandler &handler) { | |||
3094 | if (Sub.Invalid) | |||
3095 | // A diagnostic will have already been produced. | |||
3096 | return handler.failed(); | |||
3097 | if (Sub.isOnePastTheEnd() || Sub.isMostDerivedAnUnsizedArray()) { | |||
3098 | if (Info.getLangOpts().CPlusPlus11) | |||
3099 | Info.FFDiag(E, Sub.isOnePastTheEnd() | |||
3100 | ? diag::note_constexpr_access_past_end | |||
3101 | : diag::note_constexpr_access_unsized_array) | |||
3102 | << handler.AccessKind; | |||
3103 | else | |||
3104 | Info.FFDiag(E); | |||
3105 | return handler.failed(); | |||
3106 | } | |||
3107 | ||||
3108 | APValue *O = Obj.Value; | |||
3109 | QualType ObjType = Obj.Type; | |||
3110 | const FieldDecl *LastField = nullptr; | |||
3111 | const FieldDecl *VolatileField = nullptr; | |||
3112 | ||||
3113 | // Walk the designator's path to find the subobject. | |||
3114 | for (unsigned I = 0, N = Sub.Entries.size(); /**/; ++I) { | |||
3115 | // Reading an indeterminate value is undefined, but assigning over one is OK. | |||
3116 | if (O->isAbsent() || | |||
3117 | (O->isIndeterminate() && handler.AccessKind != AK_Assign && | |||
3118 | handler.AccessKind != AK_ReadObjectRepresentation)) { | |||
3119 | if (!Info.checkingPotentialConstantExpression()) | |||
3120 | Info.FFDiag(E, diag::note_constexpr_access_uninit) | |||
3121 | << handler.AccessKind << O->isIndeterminate(); | |||
3122 | return handler.failed(); | |||
3123 | } | |||
3124 | ||||
3125 | // C++ [class.ctor]p5, C++ [class.dtor]p5: | |||
3126 | // const and volatile semantics are not applied on an object under | |||
3127 | // {con,de}struction. | |||
3128 | if ((ObjType.isConstQualified() || ObjType.isVolatileQualified()) && | |||
3129 | ObjType->isRecordType() && | |||
3130 | Info.isEvaluatingCtorDtor( | |||
3131 | Obj.Base, llvm::makeArrayRef(Sub.Entries.begin(), | |||
3132 | Sub.Entries.begin() + I)) != | |||
3133 | ConstructionPhase::None) { | |||
3134 | ObjType = Info.Ctx.getCanonicalType(ObjType); | |||
3135 | ObjType.removeLocalConst(); | |||
3136 | ObjType.removeLocalVolatile(); | |||
3137 | } | |||
3138 | ||||
3139 | // If this is our last pass, check that the final object type is OK. | |||
3140 | if (I == N || (I == N - 1 && ObjType->isAnyComplexType())) { | |||
3141 | // Accesses to volatile objects are prohibited. | |||
3142 | if (ObjType.isVolatileQualified() && isFormalAccess(handler.AccessKind)) { | |||
3143 | if (Info.getLangOpts().CPlusPlus) { | |||
3144 | int DiagKind; | |||
3145 | SourceLocation Loc; | |||
3146 | const NamedDecl *Decl = nullptr; | |||
3147 | if (VolatileField) { | |||
3148 | DiagKind = 2; | |||
3149 | Loc = VolatileField->getLocation(); | |||
3150 | Decl = VolatileField; | |||
3151 | } else if (auto *VD = Obj.Base.dyn_cast<const ValueDecl*>()) { | |||
3152 | DiagKind = 1; | |||
3153 | Loc = VD->getLocation(); | |||
3154 | Decl = VD; | |||
3155 | } else { | |||
3156 | DiagKind = 0; | |||
3157 | if (auto *E = Obj.Base.dyn_cast<const Expr *>()) | |||
3158 | Loc = E->getExprLoc(); | |||
3159 | } | |||
3160 | Info.FFDiag(E, diag::note_constexpr_access_volatile_obj, 1) | |||
3161 | << handler.AccessKind << DiagKind << Decl; | |||
3162 | Info.Note(Loc, diag::note_constexpr_volatile_here) << DiagKind; | |||
3163 | } else { | |||
3164 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
3165 | } | |||
3166 | return handler.failed(); | |||
3167 | } | |||
3168 | ||||
3169 | // If we are reading an object of class type, there may still be more | |||
3170 | // things we need to check: if there are any mutable subobjects, we | |||
3171 | // cannot perform this read. (This only happens when performing a trivial | |||
3172 | // copy or assignment.) | |||
3173 | if (ObjType->isRecordType() && | |||
3174 | !Obj.mayAccessMutableMembers(Info, handler.AccessKind) && | |||
3175 | diagnoseMutableFields(Info, E, handler.AccessKind, ObjType)) | |||
3176 | return handler.failed(); | |||
3177 | } | |||
3178 | ||||
3179 | if (I == N) { | |||
3180 | if (!handler.found(*O, ObjType)) | |||
3181 | return false; | |||
3182 | ||||
3183 | // If we modified a bit-field, truncate it to the right width. | |||
3184 | if (isModification(handler.AccessKind) && | |||
3185 | LastField && LastField->isBitField() && | |||
3186 | !truncateBitfieldValue(Info, E, *O, LastField)) | |||
3187 | return false; | |||
3188 | ||||
3189 | return true; | |||
3190 | } | |||
3191 | ||||
3192 | LastField = nullptr; | |||
3193 | if (ObjType->isArrayType()) { | |||
3194 | // Next subobject is an array element. | |||
3195 | const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(ObjType); | |||
3196 | assert(CAT && "vla in literal type?")((CAT && "vla in literal type?") ? static_cast<void > (0) : __assert_fail ("CAT && \"vla in literal type?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3196, __PRETTY_FUNCTION__)); | |||
3197 | uint64_t Index = Sub.Entries[I].getAsArrayIndex(); | |||
3198 | if (CAT->getSize().ule(Index)) { | |||
3199 | // Note, it should not be possible to form a pointer with a valid | |||
3200 | // designator which points more than one past the end of the array. | |||
3201 | if (Info.getLangOpts().CPlusPlus11) | |||
3202 | Info.FFDiag(E, diag::note_constexpr_access_past_end) | |||
3203 | << handler.AccessKind; | |||
3204 | else | |||
3205 | Info.FFDiag(E); | |||
3206 | return handler.failed(); | |||
3207 | } | |||
3208 | ||||
3209 | ObjType = CAT->getElementType(); | |||
3210 | ||||
3211 | if (O->getArrayInitializedElts() > Index) | |||
3212 | O = &O->getArrayInitializedElt(Index); | |||
3213 | else if (!isRead(handler.AccessKind)) { | |||
3214 | expandArray(*O, Index); | |||
3215 | O = &O->getArrayInitializedElt(Index); | |||
3216 | } else | |||
3217 | O = &O->getArrayFiller(); | |||
3218 | } else if (ObjType->isAnyComplexType()) { | |||
3219 | // Next subobject is a complex number. | |||
3220 | uint64_t Index = Sub.Entries[I].getAsArrayIndex(); | |||
3221 | if (Index > 1) { | |||
3222 | if (Info.getLangOpts().CPlusPlus11) | |||
3223 | Info.FFDiag(E, diag::note_constexpr_access_past_end) | |||
3224 | << handler.AccessKind; | |||
3225 | else | |||
3226 | Info.FFDiag(E); | |||
3227 | return handler.failed(); | |||
3228 | } | |||
3229 | ||||
3230 | ObjType = getSubobjectType( | |||
3231 | ObjType, ObjType->castAs<ComplexType>()->getElementType()); | |||
3232 | ||||
3233 | assert(I == N - 1 && "extracting subobject of scalar?")((I == N - 1 && "extracting subobject of scalar?") ? static_cast <void> (0) : __assert_fail ("I == N - 1 && \"extracting subobject of scalar?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3233, __PRETTY_FUNCTION__)); | |||
3234 | if (O->isComplexInt()) { | |||
3235 | return handler.found(Index ? O->getComplexIntImag() | |||
3236 | : O->getComplexIntReal(), ObjType); | |||
3237 | } else { | |||
3238 | assert(O->isComplexFloat())((O->isComplexFloat()) ? static_cast<void> (0) : __assert_fail ("O->isComplexFloat()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3238, __PRETTY_FUNCTION__)); | |||
3239 | return handler.found(Index ? O->getComplexFloatImag() | |||
3240 | : O->getComplexFloatReal(), ObjType); | |||
3241 | } | |||
3242 | } else if (const FieldDecl *Field = getAsField(Sub.Entries[I])) { | |||
3243 | if (Field->isMutable() && | |||
3244 | !Obj.mayAccessMutableMembers(Info, handler.AccessKind)) { | |||
3245 | Info.FFDiag(E, diag::note_constexpr_access_mutable, 1) | |||
3246 | << handler.AccessKind << Field; | |||
3247 | Info.Note(Field->getLocation(), diag::note_declared_at); | |||
3248 | return handler.failed(); | |||
3249 | } | |||
3250 | ||||
3251 | // Next subobject is a class, struct or union field. | |||
3252 | RecordDecl *RD = ObjType->castAs<RecordType>()->getDecl(); | |||
3253 | if (RD->isUnion()) { | |||
3254 | const FieldDecl *UnionField = O->getUnionField(); | |||
3255 | if (!UnionField || | |||
3256 | UnionField->getCanonicalDecl() != Field->getCanonicalDecl()) { | |||
3257 | // FIXME: If O->getUnionValue() is absent, report that there's no | |||
3258 | // active union member rather than reporting the prior active union | |||
3259 | // member. We'll need to fix nullptr_t to not use APValue() as its | |||
3260 | // representation first. | |||
3261 | Info.FFDiag(E, diag::note_constexpr_access_inactive_union_member) | |||
3262 | << handler.AccessKind << Field << !UnionField << UnionField; | |||
3263 | return handler.failed(); | |||
3264 | } | |||
3265 | O = &O->getUnionValue(); | |||
3266 | } else | |||
3267 | O = &O->getStructField(Field->getFieldIndex()); | |||
3268 | ||||
3269 | ObjType = getSubobjectType(ObjType, Field->getType(), Field->isMutable()); | |||
3270 | LastField = Field; | |||
3271 | if (Field->getType().isVolatileQualified()) | |||
3272 | VolatileField = Field; | |||
3273 | } else { | |||
3274 | // Next subobject is a base class. | |||
3275 | const CXXRecordDecl *Derived = ObjType->getAsCXXRecordDecl(); | |||
3276 | const CXXRecordDecl *Base = getAsBaseClass(Sub.Entries[I]); | |||
3277 | O = &O->getStructBase(getBaseIndex(Derived, Base)); | |||
3278 | ||||
3279 | ObjType = getSubobjectType(ObjType, Info.Ctx.getRecordType(Base)); | |||
3280 | } | |||
3281 | } | |||
3282 | } | |||
3283 | ||||
3284 | namespace { | |||
3285 | struct ExtractSubobjectHandler { | |||
3286 | EvalInfo &Info; | |||
3287 | const Expr *E; | |||
3288 | APValue &Result; | |||
3289 | const AccessKinds AccessKind; | |||
3290 | ||||
3291 | typedef bool result_type; | |||
3292 | bool failed() { return false; } | |||
3293 | bool found(APValue &Subobj, QualType SubobjType) { | |||
3294 | Result = Subobj; | |||
3295 | if (AccessKind == AK_ReadObjectRepresentation) | |||
3296 | return true; | |||
3297 | return CheckFullyInitialized(Info, E->getExprLoc(), SubobjType, Result); | |||
3298 | } | |||
3299 | bool found(APSInt &Value, QualType SubobjType) { | |||
3300 | Result = APValue(Value); | |||
3301 | return true; | |||
3302 | } | |||
3303 | bool found(APFloat &Value, QualType SubobjType) { | |||
3304 | Result = APValue(Value); | |||
3305 | return true; | |||
3306 | } | |||
3307 | }; | |||
3308 | } // end anonymous namespace | |||
3309 | ||||
3310 | /// Extract the designated sub-object of an rvalue. | |||
3311 | static bool extractSubobject(EvalInfo &Info, const Expr *E, | |||
3312 | const CompleteObject &Obj, | |||
3313 | const SubobjectDesignator &Sub, APValue &Result, | |||
3314 | AccessKinds AK = AK_Read) { | |||
3315 | assert(AK == AK_Read || AK == AK_ReadObjectRepresentation)((AK == AK_Read || AK == AK_ReadObjectRepresentation) ? static_cast <void> (0) : __assert_fail ("AK == AK_Read || AK == AK_ReadObjectRepresentation" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3315, __PRETTY_FUNCTION__)); | |||
3316 | ExtractSubobjectHandler Handler = {Info, E, Result, AK}; | |||
3317 | return findSubobject(Info, E, Obj, Sub, Handler); | |||
3318 | } | |||
3319 | ||||
3320 | namespace { | |||
3321 | struct ModifySubobjectHandler { | |||
3322 | EvalInfo &Info; | |||
3323 | APValue &NewVal; | |||
3324 | const Expr *E; | |||
3325 | ||||
3326 | typedef bool result_type; | |||
3327 | static const AccessKinds AccessKind = AK_Assign; | |||
3328 | ||||
3329 | bool checkConst(QualType QT) { | |||
3330 | // Assigning to a const object has undefined behavior. | |||
3331 | if (QT.isConstQualified()) { | |||
3332 | Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT; | |||
3333 | return false; | |||
3334 | } | |||
3335 | return true; | |||
3336 | } | |||
3337 | ||||
3338 | bool failed() { return false; } | |||
3339 | bool found(APValue &Subobj, QualType SubobjType) { | |||
3340 | if (!checkConst(SubobjType)) | |||
3341 | return false; | |||
3342 | // We've been given ownership of NewVal, so just swap it in. | |||
3343 | Subobj.swap(NewVal); | |||
3344 | return true; | |||
3345 | } | |||
3346 | bool found(APSInt &Value, QualType SubobjType) { | |||
3347 | if (!checkConst(SubobjType)) | |||
3348 | return false; | |||
3349 | if (!NewVal.isInt()) { | |||
3350 | // Maybe trying to write a cast pointer value into a complex? | |||
3351 | Info.FFDiag(E); | |||
3352 | return false; | |||
3353 | } | |||
3354 | Value = NewVal.getInt(); | |||
3355 | return true; | |||
3356 | } | |||
3357 | bool found(APFloat &Value, QualType SubobjType) { | |||
3358 | if (!checkConst(SubobjType)) | |||
3359 | return false; | |||
3360 | Value = NewVal.getFloat(); | |||
3361 | return true; | |||
3362 | } | |||
3363 | }; | |||
3364 | } // end anonymous namespace | |||
3365 | ||||
3366 | const AccessKinds ModifySubobjectHandler::AccessKind; | |||
3367 | ||||
3368 | /// Update the designated sub-object of an rvalue to the given value. | |||
3369 | static bool modifySubobject(EvalInfo &Info, const Expr *E, | |||
3370 | const CompleteObject &Obj, | |||
3371 | const SubobjectDesignator &Sub, | |||
3372 | APValue &NewVal) { | |||
3373 | ModifySubobjectHandler Handler = { Info, NewVal, E }; | |||
3374 | return findSubobject(Info, E, Obj, Sub, Handler); | |||
3375 | } | |||
3376 | ||||
3377 | /// Find the position where two subobject designators diverge, or equivalently | |||
3378 | /// the length of the common initial subsequence. | |||
3379 | static unsigned FindDesignatorMismatch(QualType ObjType, | |||
3380 | const SubobjectDesignator &A, | |||
3381 | const SubobjectDesignator &B, | |||
3382 | bool &WasArrayIndex) { | |||
3383 | unsigned I = 0, N = std::min(A.Entries.size(), B.Entries.size()); | |||
3384 | for (/**/; I != N; ++I) { | |||
3385 | if (!ObjType.isNull() && | |||
3386 | (ObjType->isArrayType() || ObjType->isAnyComplexType())) { | |||
3387 | // Next subobject is an array element. | |||
3388 | if (A.Entries[I].getAsArrayIndex() != B.Entries[I].getAsArrayIndex()) { | |||
3389 | WasArrayIndex = true; | |||
3390 | return I; | |||
3391 | } | |||
3392 | if (ObjType->isAnyComplexType()) | |||
3393 | ObjType = ObjType->castAs<ComplexType>()->getElementType(); | |||
3394 | else | |||
3395 | ObjType = ObjType->castAsArrayTypeUnsafe()->getElementType(); | |||
3396 | } else { | |||
3397 | if (A.Entries[I].getAsBaseOrMember() != | |||
3398 | B.Entries[I].getAsBaseOrMember()) { | |||
3399 | WasArrayIndex = false; | |||
3400 | return I; | |||
3401 | } | |||
3402 | if (const FieldDecl *FD = getAsField(A.Entries[I])) | |||
3403 | // Next subobject is a field. | |||
3404 | ObjType = FD->getType(); | |||
3405 | else | |||
3406 | // Next subobject is a base class. | |||
3407 | ObjType = QualType(); | |||
3408 | } | |||
3409 | } | |||
3410 | WasArrayIndex = false; | |||
3411 | return I; | |||
3412 | } | |||
3413 | ||||
3414 | /// Determine whether the given subobject designators refer to elements of the | |||
3415 | /// same array object. | |||
3416 | static bool AreElementsOfSameArray(QualType ObjType, | |||
3417 | const SubobjectDesignator &A, | |||
3418 | const SubobjectDesignator &B) { | |||
3419 | if (A.Entries.size() != B.Entries.size()) | |||
3420 | return false; | |||
3421 | ||||
3422 | bool IsArray = A.MostDerivedIsArrayElement; | |||
3423 | if (IsArray && A.MostDerivedPathLength != A.Entries.size()) | |||
3424 | // A is a subobject of the array element. | |||
3425 | return false; | |||
3426 | ||||
3427 | // If A (and B) designates an array element, the last entry will be the array | |||
3428 | // index. That doesn't have to match. Otherwise, we're in the 'implicit array | |||
3429 | // of length 1' case, and the entire path must match. | |||
3430 | bool WasArrayIndex; | |||
3431 | unsigned CommonLength = FindDesignatorMismatch(ObjType, A, B, WasArrayIndex); | |||
3432 | return CommonLength >= A.Entries.size() - IsArray; | |||
3433 | } | |||
3434 | ||||
3435 | /// Find the complete object to which an LValue refers. | |||
3436 | static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E, | |||
3437 | AccessKinds AK, const LValue &LVal, | |||
3438 | QualType LValType) { | |||
3439 | if (LVal.InvalidBase) { | |||
3440 | Info.FFDiag(E); | |||
3441 | return CompleteObject(); | |||
3442 | } | |||
3443 | ||||
3444 | if (!LVal.Base) { | |||
3445 | Info.FFDiag(E, diag::note_constexpr_access_null) << AK; | |||
3446 | return CompleteObject(); | |||
3447 | } | |||
3448 | ||||
3449 | CallStackFrame *Frame = nullptr; | |||
3450 | unsigned Depth = 0; | |||
3451 | if (LVal.getLValueCallIndex()) { | |||
3452 | std::tie(Frame, Depth) = | |||
3453 | Info.getCallFrameAndDepth(LVal.getLValueCallIndex()); | |||
3454 | if (!Frame) { | |||
3455 | Info.FFDiag(E, diag::note_constexpr_lifetime_ended, 1) | |||
3456 | << AK << LVal.Base.is<const ValueDecl*>(); | |||
3457 | NoteLValueLocation(Info, LVal.Base); | |||
3458 | return CompleteObject(); | |||
3459 | } | |||
3460 | } | |||
3461 | ||||
3462 | bool IsAccess = isAnyAccess(AK); | |||
3463 | ||||
3464 | // C++11 DR1311: An lvalue-to-rvalue conversion on a volatile-qualified type | |||
3465 | // is not a constant expression (even if the object is non-volatile). We also | |||
3466 | // apply this rule to C++98, in order to conform to the expected 'volatile' | |||
3467 | // semantics. | |||
3468 | if (isFormalAccess(AK) && LValType.isVolatileQualified()) { | |||
3469 | if (Info.getLangOpts().CPlusPlus) | |||
3470 | Info.FFDiag(E, diag::note_constexpr_access_volatile_type) | |||
3471 | << AK << LValType; | |||
3472 | else | |||
3473 | Info.FFDiag(E); | |||
3474 | return CompleteObject(); | |||
3475 | } | |||
3476 | ||||
3477 | // Compute value storage location and type of base object. | |||
3478 | APValue *BaseVal = nullptr; | |||
3479 | QualType BaseType = getType(LVal.Base); | |||
3480 | ||||
3481 | if (const ValueDecl *D = LVal.Base.dyn_cast<const ValueDecl*>()) { | |||
3482 | // In C++98, const, non-volatile integers initialized with ICEs are ICEs. | |||
3483 | // In C++11, constexpr, non-volatile variables initialized with constant | |||
3484 | // expressions are constant expressions too. Inside constexpr functions, | |||
3485 | // parameters are constant expressions even if they're non-const. | |||
3486 | // In C++1y, objects local to a constant expression (those with a Frame) are | |||
3487 | // both readable and writable inside constant expressions. | |||
3488 | // In C, such things can also be folded, although they are not ICEs. | |||
3489 | const VarDecl *VD = dyn_cast<VarDecl>(D); | |||
3490 | if (VD) { | |||
3491 | if (const VarDecl *VDef = VD->getDefinition(Info.Ctx)) | |||
3492 | VD = VDef; | |||
3493 | } | |||
3494 | if (!VD || VD->isInvalidDecl()) { | |||
3495 | Info.FFDiag(E); | |||
3496 | return CompleteObject(); | |||
3497 | } | |||
3498 | ||||
3499 | // Unless we're looking at a local variable or argument in a constexpr call, | |||
3500 | // the variable we're reading must be const. | |||
3501 | if (!Frame) { | |||
3502 | if (Info.getLangOpts().CPlusPlus14 && | |||
3503 | lifetimeStartedInEvaluation(Info, LVal.Base)) { | |||
3504 | // OK, we can read and modify an object if we're in the process of | |||
3505 | // evaluating its initializer, because its lifetime began in this | |||
3506 | // evaluation. | |||
3507 | } else if (isModification(AK)) { | |||
3508 | // All the remaining cases do not permit modification of the object. | |||
3509 | Info.FFDiag(E, diag::note_constexpr_modify_global); | |||
3510 | return CompleteObject(); | |||
3511 | } else if (VD->isConstexpr()) { | |||
3512 | // OK, we can read this variable. | |||
3513 | } else if (BaseType->isIntegralOrEnumerationType()) { | |||
3514 | // In OpenCL if a variable is in constant address space it is a const | |||
3515 | // value. | |||
3516 | if (!(BaseType.isConstQualified() || | |||
3517 | (Info.getLangOpts().OpenCL && | |||
3518 | BaseType.getAddressSpace() == LangAS::opencl_constant))) { | |||
3519 | if (!IsAccess) | |||
3520 | return CompleteObject(LVal.getLValueBase(), nullptr, BaseType); | |||
3521 | if (Info.getLangOpts().CPlusPlus) { | |||
3522 | Info.FFDiag(E, diag::note_constexpr_ltor_non_const_int, 1) << VD; | |||
3523 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
3524 | } else { | |||
3525 | Info.FFDiag(E); | |||
3526 | } | |||
3527 | return CompleteObject(); | |||
3528 | } | |||
3529 | } else if (!IsAccess) { | |||
3530 | return CompleteObject(LVal.getLValueBase(), nullptr, BaseType); | |||
3531 | } else if (BaseType->isFloatingType() && BaseType.isConstQualified()) { | |||
3532 | // We support folding of const floating-point types, in order to make | |||
3533 | // static const data members of such types (supported as an extension) | |||
3534 | // more useful. | |||
3535 | if (Info.getLangOpts().CPlusPlus11) { | |||
3536 | Info.CCEDiag(E, diag::note_constexpr_ltor_non_constexpr, 1) << VD; | |||
3537 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
3538 | } else { | |||
3539 | Info.CCEDiag(E); | |||
3540 | } | |||
3541 | } else if (BaseType.isConstQualified() && VD->hasDefinition(Info.Ctx)) { | |||
3542 | Info.CCEDiag(E, diag::note_constexpr_ltor_non_constexpr) << VD; | |||
3543 | // Keep evaluating to see what we can do. | |||
3544 | } else { | |||
3545 | // FIXME: Allow folding of values of any literal type in all languages. | |||
3546 | if (Info.checkingPotentialConstantExpression() && | |||
3547 | VD->getType().isConstQualified() && !VD->hasDefinition(Info.Ctx)) { | |||
3548 | // The definition of this variable could be constexpr. We can't | |||
3549 | // access it right now, but may be able to in future. | |||
3550 | } else if (Info.getLangOpts().CPlusPlus11) { | |||
3551 | Info.FFDiag(E, diag::note_constexpr_ltor_non_constexpr, 1) << VD; | |||
3552 | Info.Note(VD->getLocation(), diag::note_declared_at); | |||
3553 | } else { | |||
3554 | Info.FFDiag(E); | |||
3555 | } | |||
3556 | return CompleteObject(); | |||
3557 | } | |||
3558 | } | |||
3559 | ||||
3560 | if (!evaluateVarDeclInit(Info, E, VD, Frame, BaseVal, &LVal)) | |||
3561 | return CompleteObject(); | |||
3562 | } else if (DynamicAllocLValue DA = LVal.Base.dyn_cast<DynamicAllocLValue>()) { | |||
3563 | Optional<EvalInfo::DynAlloc*> Alloc = Info.lookupDynamicAlloc(DA); | |||
3564 | if (!Alloc) { | |||
3565 | Info.FFDiag(E, diag::note_constexpr_access_deleted_object) << AK; | |||
3566 | return CompleteObject(); | |||
3567 | } | |||
3568 | return CompleteObject(LVal.Base, &(*Alloc)->Value, | |||
3569 | LVal.Base.getDynamicAllocType()); | |||
3570 | } else { | |||
3571 | const Expr *Base = LVal.Base.dyn_cast<const Expr*>(); | |||
3572 | ||||
3573 | if (!Frame) { | |||
3574 | if (const MaterializeTemporaryExpr *MTE = | |||
3575 | dyn_cast_or_null<MaterializeTemporaryExpr>(Base)) { | |||
3576 | assert(MTE->getStorageDuration() == SD_Static &&((MTE->getStorageDuration() == SD_Static && "should have a frame for a non-global materialized temporary" ) ? static_cast<void> (0) : __assert_fail ("MTE->getStorageDuration() == SD_Static && \"should have a frame for a non-global materialized temporary\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3577, __PRETTY_FUNCTION__)) | |||
3577 | "should have a frame for a non-global materialized temporary")((MTE->getStorageDuration() == SD_Static && "should have a frame for a non-global materialized temporary" ) ? static_cast<void> (0) : __assert_fail ("MTE->getStorageDuration() == SD_Static && \"should have a frame for a non-global materialized temporary\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3577, __PRETTY_FUNCTION__)); | |||
3578 | ||||
3579 | // Per C++1y [expr.const]p2: | |||
3580 | // an lvalue-to-rvalue conversion [is not allowed unless it applies to] | |||
3581 | // - a [...] glvalue of integral or enumeration type that refers to | |||
3582 | // a non-volatile const object [...] | |||
3583 | // [...] | |||
3584 | // - a [...] glvalue of literal type that refers to a non-volatile | |||
3585 | // object whose lifetime began within the evaluation of e. | |||
3586 | // | |||
3587 | // C++11 misses the 'began within the evaluation of e' check and | |||
3588 | // instead allows all temporaries, including things like: | |||
3589 | // int &&r = 1; | |||
3590 | // int x = ++r; | |||
3591 | // constexpr int k = r; | |||
3592 | // Therefore we use the C++14 rules in C++11 too. | |||
3593 | // | |||
3594 | // Note that temporaries whose lifetimes began while evaluating a | |||
3595 | // variable's constructor are not usable while evaluating the | |||
3596 | // corresponding destructor, not even if they're of const-qualified | |||
3597 | // types. | |||
3598 | if (!(BaseType.isConstQualified() && | |||
3599 | BaseType->isIntegralOrEnumerationType()) && | |||
3600 | !lifetimeStartedInEvaluation(Info, LVal.Base)) { | |||
3601 | if (!IsAccess) | |||
3602 | return CompleteObject(LVal.getLValueBase(), nullptr, BaseType); | |||
3603 | Info.FFDiag(E, diag::note_constexpr_access_static_temporary, 1) << AK; | |||
3604 | Info.Note(MTE->getExprLoc(), diag::note_constexpr_temporary_here); | |||
3605 | return CompleteObject(); | |||
3606 | } | |||
3607 | ||||
3608 | BaseVal = Info.Ctx.getMaterializedTemporaryValue(MTE, false); | |||
3609 | assert(BaseVal && "got reference to unevaluated temporary")((BaseVal && "got reference to unevaluated temporary" ) ? static_cast<void> (0) : __assert_fail ("BaseVal && \"got reference to unevaluated temporary\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3609, __PRETTY_FUNCTION__)); | |||
3610 | } else { | |||
3611 | if (!IsAccess) | |||
3612 | return CompleteObject(LVal.getLValueBase(), nullptr, BaseType); | |||
3613 | APValue Val; | |||
3614 | LVal.moveInto(Val); | |||
3615 | Info.FFDiag(E, diag::note_constexpr_access_unreadable_object) | |||
3616 | << AK | |||
3617 | << Val.getAsString(Info.Ctx, | |||
3618 | Info.Ctx.getLValueReferenceType(LValType)); | |||
3619 | NoteLValueLocation(Info, LVal.Base); | |||
3620 | return CompleteObject(); | |||
3621 | } | |||
3622 | } else { | |||
3623 | BaseVal = Frame->getTemporary(Base, LVal.Base.getVersion()); | |||
3624 | assert(BaseVal && "missing value for temporary")((BaseVal && "missing value for temporary") ? static_cast <void> (0) : __assert_fail ("BaseVal && \"missing value for temporary\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3624, __PRETTY_FUNCTION__)); | |||
3625 | } | |||
3626 | } | |||
3627 | ||||
3628 | // In C++14, we can't safely access any mutable state when we might be | |||
3629 | // evaluating after an unmodeled side effect. | |||
3630 | // | |||
3631 | // FIXME: Not all local state is mutable. Allow local constant subobjects | |||
3632 | // to be read here (but take care with 'mutable' fields). | |||
3633 | if ((Frame && Info.getLangOpts().CPlusPlus14 && | |||
3634 | Info.EvalStatus.HasSideEffects) || | |||
3635 | (isModification(AK) && Depth < Info.SpeculativeEvaluationDepth)) | |||
3636 | return CompleteObject(); | |||
3637 | ||||
3638 | return CompleteObject(LVal.getLValueBase(), BaseVal, BaseType); | |||
3639 | } | |||
3640 | ||||
3641 | /// Perform an lvalue-to-rvalue conversion on the given glvalue. This | |||
3642 | /// can also be used for 'lvalue-to-lvalue' conversions for looking up the | |||
3643 | /// glvalue referred to by an entity of reference type. | |||
3644 | /// | |||
3645 | /// \param Info - Information about the ongoing evaluation. | |||
3646 | /// \param Conv - The expression for which we are performing the conversion. | |||
3647 | /// Used for diagnostics. | |||
3648 | /// \param Type - The type of the glvalue (before stripping cv-qualifiers in the | |||
3649 | /// case of a non-class type). | |||
3650 | /// \param LVal - The glvalue on which we are attempting to perform this action. | |||
3651 | /// \param RVal - The produced value will be placed here. | |||
3652 | /// \param WantObjectRepresentation - If true, we're looking for the object | |||
3653 | /// representation rather than the value, and in particular, | |||
3654 | /// there is no requirement that the result be fully initialized. | |||
3655 | static bool | |||
3656 | handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv, QualType Type, | |||
3657 | const LValue &LVal, APValue &RVal, | |||
3658 | bool WantObjectRepresentation = false) { | |||
3659 | if (LVal.Designator.Invalid) | |||
3660 | return false; | |||
3661 | ||||
3662 | // Check for special cases where there is no existing APValue to look at. | |||
3663 | const Expr *Base = LVal.Base.dyn_cast<const Expr*>(); | |||
3664 | ||||
3665 | AccessKinds AK = | |||
3666 | WantObjectRepresentation ? AK_ReadObjectRepresentation : AK_Read; | |||
3667 | ||||
3668 | if (Base && !LVal.getLValueCallIndex() && !Type.isVolatileQualified()) { | |||
3669 | if (const CompoundLiteralExpr *CLE = dyn_cast<CompoundLiteralExpr>(Base)) { | |||
3670 | // In C99, a CompoundLiteralExpr is an lvalue, and we defer evaluating the | |||
3671 | // initializer until now for such expressions. Such an expression can't be | |||
3672 | // an ICE in C, so this only matters for fold. | |||
3673 | if (Type.isVolatileQualified()) { | |||
3674 | Info.FFDiag(Conv); | |||
3675 | return false; | |||
3676 | } | |||
3677 | APValue Lit; | |||
3678 | if (!Evaluate(Lit, Info, CLE->getInitializer())) | |||
3679 | return false; | |||
3680 | CompleteObject LitObj(LVal.Base, &Lit, Base->getType()); | |||
3681 | return extractSubobject(Info, Conv, LitObj, LVal.Designator, RVal, AK); | |||
3682 | } else if (isa<StringLiteral>(Base) || isa<PredefinedExpr>(Base)) { | |||
3683 | // Special-case character extraction so we don't have to construct an | |||
3684 | // APValue for the whole string. | |||
3685 | assert(LVal.Designator.Entries.size() <= 1 &&((LVal.Designator.Entries.size() <= 1 && "Can only read characters from string literals" ) ? static_cast<void> (0) : __assert_fail ("LVal.Designator.Entries.size() <= 1 && \"Can only read characters from string literals\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3686, __PRETTY_FUNCTION__)) | |||
3686 | "Can only read characters from string literals")((LVal.Designator.Entries.size() <= 1 && "Can only read characters from string literals" ) ? static_cast<void> (0) : __assert_fail ("LVal.Designator.Entries.size() <= 1 && \"Can only read characters from string literals\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 3686, __PRETTY_FUNCTION__)); | |||
3687 | if (LVal.Designator.Entries.empty()) { | |||
3688 | // Fail for now for LValue to RValue conversion of an array. | |||
3689 | // (This shouldn't show up in C/C++, but it could be triggered by a | |||
3690 | // weird EvaluateAsRValue call from a tool.) | |||
3691 | Info.FFDiag(Conv); | |||
3692 | return false; | |||
3693 | } | |||
3694 | if (LVal.Designator.isOnePastTheEnd()) { | |||
3695 | if (Info.getLangOpts().CPlusPlus11) | |||
3696 | Info.FFDiag(Conv, diag::note_constexpr_access_past_end) << AK; | |||
3697 | else | |||
3698 | Info.FFDiag(Conv); | |||
3699 | return false; | |||
3700 | } | |||
3701 | uint64_t CharIndex = LVal.Designator.Entries[0].getAsArrayIndex(); | |||
3702 | RVal = APValue(extractStringLiteralCharacter(Info, Base, CharIndex)); | |||
3703 | return true; | |||
3704 | } | |||
3705 | } | |||
3706 | ||||
3707 | CompleteObject Obj = findCompleteObject(Info, Conv, AK, LVal, Type); | |||
3708 | return Obj && extractSubobject(Info, Conv, Obj, LVal.Designator, RVal, AK); | |||
3709 | } | |||
3710 | ||||
3711 | /// Perform an assignment of Val to LVal. Takes ownership of Val. | |||
3712 | static bool handleAssignment(EvalInfo &Info, const Expr *E, const LValue &LVal, | |||
3713 | QualType LValType, APValue &Val) { | |||
3714 | if (LVal.Designator.Invalid) | |||
3715 | return false; | |||
3716 | ||||
3717 | if (!Info.getLangOpts().CPlusPlus14) { | |||
3718 | Info.FFDiag(E); | |||
3719 | return false; | |||
3720 | } | |||
3721 | ||||
3722 | CompleteObject Obj = findCompleteObject(Info, E, AK_Assign, LVal, LValType); | |||
3723 | return Obj && modifySubobject(Info, E, Obj, LVal.Designator, Val); | |||
3724 | } | |||
3725 | ||||
3726 | namespace { | |||
3727 | struct CompoundAssignSubobjectHandler { | |||
3728 | EvalInfo &Info; | |||
3729 | const Expr *E; | |||
3730 | QualType PromotedLHSType; | |||
3731 | BinaryOperatorKind Opcode; | |||
3732 | const APValue &RHS; | |||
3733 | ||||
3734 | static const AccessKinds AccessKind = AK_Assign; | |||
3735 | ||||
3736 | typedef bool result_type; | |||
3737 | ||||
3738 | bool checkConst(QualType QT) { | |||
3739 | // Assigning to a const object has undefined behavior. | |||
3740 | if (QT.isConstQualified()) { | |||
3741 | Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT; | |||
3742 | return false; | |||
3743 | } | |||
3744 | return true; | |||
3745 | } | |||
3746 | ||||
3747 | bool failed() { return false; } | |||
3748 | bool found(APValue &Subobj, QualType SubobjType) { | |||
3749 | switch (Subobj.getKind()) { | |||
3750 | case APValue::Int: | |||
3751 | return found(Subobj.getInt(), SubobjType); | |||
3752 | case APValue::Float: | |||
3753 | return found(Subobj.getFloat(), SubobjType); | |||
3754 | case APValue::ComplexInt: | |||
3755 | case APValue::ComplexFloat: | |||
3756 | // FIXME: Implement complex compound assignment. | |||
3757 | Info.FFDiag(E); | |||
3758 | return false; | |||
3759 | case APValue::LValue: | |||
3760 | return foundPointer(Subobj, SubobjType); | |||
3761 | default: | |||
3762 | // FIXME: can this happen? | |||
3763 | Info.FFDiag(E); | |||
3764 | return false; | |||
3765 | } | |||
3766 | } | |||
3767 | bool found(APSInt &Value, QualType SubobjType) { | |||
3768 | if (!checkConst(SubobjType)) | |||
3769 | return false; | |||
3770 | ||||
3771 | if (!SubobjType->isIntegerType()) { | |||
3772 | // We don't support compound assignment on integer-cast-to-pointer | |||
3773 | // values. | |||
3774 | Info.FFDiag(E); | |||
3775 | return false; | |||
3776 | } | |||
3777 | ||||
3778 | if (RHS.isInt()) { | |||
3779 | APSInt LHS = | |||
3780 | HandleIntToIntCast(Info, E, PromotedLHSType, SubobjType, Value); | |||
3781 | if (!handleIntIntBinOp(Info, E, LHS, Opcode, RHS.getInt(), LHS)) | |||
3782 | return false; | |||
3783 | Value = HandleIntToIntCast(Info, E, SubobjType, PromotedLHSType, LHS); | |||
3784 | return true; | |||
3785 | } else if (RHS.isFloat()) { | |||
3786 | APFloat FValue(0.0); | |||
3787 | return HandleIntToFloatCast(Info, E, SubobjType, Value, PromotedLHSType, | |||
3788 | FValue) && | |||
3789 | handleFloatFloatBinOp(Info, E, FValue, Opcode, RHS.getFloat()) && | |||
3790 | HandleFloatToIntCast(Info, E, PromotedLHSType, FValue, SubobjType, | |||
3791 | Value); | |||
3792 | } | |||
3793 | ||||
3794 | Info.FFDiag(E); | |||
3795 | return false; | |||
3796 | } | |||
3797 | bool found(APFloat &Value, QualType SubobjType) { | |||
3798 | return checkConst(SubobjType) && | |||
3799 | HandleFloatToFloatCast(Info, E, SubobjType, PromotedLHSType, | |||
3800 | Value) && | |||
3801 | handleFloatFloatBinOp(Info, E, Value, Opcode, RHS.getFloat()) && | |||
3802 | HandleFloatToFloatCast(Info, E, PromotedLHSType, SubobjType, Value); | |||
3803 | } | |||
3804 | bool foundPointer(APValue &Subobj, QualType SubobjType) { | |||
3805 | if (!checkConst(SubobjType)) | |||
3806 | return false; | |||
3807 | ||||
3808 | QualType PointeeType; | |||
3809 | if (const PointerType *PT = SubobjType->getAs<PointerType>()) | |||
3810 | PointeeType = PT->getPointeeType(); | |||
3811 | ||||
3812 | if (PointeeType.isNull() || !RHS.isInt() || | |||
3813 | (Opcode != BO_Add && Opcode != BO_Sub)) { | |||
3814 | Info.FFDiag(E); | |||
3815 | return false; | |||
3816 | } | |||
3817 | ||||
3818 | APSInt Offset = RHS.getInt(); | |||
3819 | if (Opcode == BO_Sub) | |||
3820 | negateAsSigned(Offset); | |||
3821 | ||||
3822 | LValue LVal; | |||
3823 | LVal.setFrom(Info.Ctx, Subobj); | |||
3824 | if (!HandleLValueArrayAdjustment(Info, E, LVal, PointeeType, Offset)) | |||
3825 | return false; | |||
3826 | LVal.moveInto(Subobj); | |||
3827 | return true; | |||
3828 | } | |||
3829 | }; | |||
3830 | } // end anonymous namespace | |||
3831 | ||||
3832 | const AccessKinds CompoundAssignSubobjectHandler::AccessKind; | |||
3833 | ||||
3834 | /// Perform a compound assignment of LVal <op>= RVal. | |||
3835 | static bool handleCompoundAssignment( | |||
3836 | EvalInfo &Info, const Expr *E, | |||
3837 | const LValue &LVal, QualType LValType, QualType PromotedLValType, | |||
3838 | BinaryOperatorKind Opcode, const APValue &RVal) { | |||
3839 | if (LVal.Designator.Invalid) | |||
3840 | return false; | |||
3841 | ||||
3842 | if (!Info.getLangOpts().CPlusPlus14) { | |||
3843 | Info.FFDiag(E); | |||
3844 | return false; | |||
3845 | } | |||
3846 | ||||
3847 | CompleteObject Obj = findCompleteObject(Info, E, AK_Assign, LVal, LValType); | |||
3848 | CompoundAssignSubobjectHandler Handler = { Info, E, PromotedLValType, Opcode, | |||
3849 | RVal }; | |||
3850 | return Obj && findSubobject(Info, E, Obj, LVal.Designator, Handler); | |||
3851 | } | |||
3852 | ||||
3853 | namespace { | |||
3854 | struct IncDecSubobjectHandler { | |||
3855 | EvalInfo &Info; | |||
3856 | const UnaryOperator *E; | |||
3857 | AccessKinds AccessKind; | |||
3858 | APValue *Old; | |||
3859 | ||||
3860 | typedef bool result_type; | |||
3861 | ||||
3862 | bool checkConst(QualType QT) { | |||
3863 | // Assigning to a const object has undefined behavior. | |||
3864 | if (QT.isConstQualified()) { | |||
3865 | Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT; | |||
3866 | return false; | |||
3867 | } | |||
3868 | return true; | |||
3869 | } | |||
3870 | ||||
3871 | bool failed() { return false; } | |||
3872 | bool found(APValue &Subobj, QualType SubobjType) { | |||
3873 | // Stash the old value. Also clear Old, so we don't clobber it later | |||
3874 | // if we're post-incrementing a complex. | |||
3875 | if (Old) { | |||
3876 | *Old = Subobj; | |||
3877 | Old = nullptr; | |||
3878 | } | |||
3879 | ||||
3880 | switch (Subobj.getKind()) { | |||
3881 | case APValue::Int: | |||
3882 | return found(Subobj.getInt(), SubobjType); | |||
3883 | case APValue::Float: | |||
3884 | return found(Subobj.getFloat(), SubobjType); | |||
3885 | case APValue::ComplexInt: | |||
3886 | return found(Subobj.getComplexIntReal(), | |||
3887 | SubobjType->castAs<ComplexType>()->getElementType() | |||
3888 | .withCVRQualifiers(SubobjType.getCVRQualifiers())); | |||
3889 | case APValue::ComplexFloat: | |||
3890 | return found(Subobj.getComplexFloatReal(), | |||
3891 | SubobjType->castAs<ComplexType>()->getElementType() | |||
3892 | .withCVRQualifiers(SubobjType.getCVRQualifiers())); | |||
3893 | case APValue::LValue: | |||
3894 | return foundPointer(Subobj, SubobjType); | |||
3895 | default: | |||
3896 | // FIXME: can this happen? | |||
3897 | Info.FFDiag(E); | |||
3898 | return false; | |||
3899 | } | |||
3900 | } | |||
3901 | bool found(APSInt &Value, QualType SubobjType) { | |||
3902 | if (!checkConst(SubobjType)) | |||
3903 | return false; | |||
3904 | ||||
3905 | if (!SubobjType->isIntegerType()) { | |||
3906 | // We don't support increment / decrement on integer-cast-to-pointer | |||
3907 | // values. | |||
3908 | Info.FFDiag(E); | |||
3909 | return false; | |||
3910 | } | |||
3911 | ||||
3912 | if (Old) *Old = APValue(Value); | |||
3913 | ||||
3914 | // bool arithmetic promotes to int, and the conversion back to bool | |||
3915 | // doesn't reduce mod 2^n, so special-case it. | |||
3916 | if (SubobjType->isBooleanType()) { | |||
3917 | if (AccessKind == AK_Increment) | |||
3918 | Value = 1; | |||
3919 | else | |||
3920 | Value = !Value; | |||
3921 | return true; | |||
3922 | } | |||
3923 | ||||
3924 | bool WasNegative = Value.isNegative(); | |||
3925 | if (AccessKind == AK_Increment) { | |||
3926 | ++Value; | |||
3927 | ||||
3928 | if (!WasNegative && Value.isNegative() && E->canOverflow()) { | |||
3929 | APSInt ActualValue(Value, /*IsUnsigned*/true); | |||
3930 | return HandleOverflow(Info, E, ActualValue, SubobjType); | |||
3931 | } | |||
3932 | } else { | |||
3933 | --Value; | |||
3934 | ||||
3935 | if (WasNegative && !Value.isNegative() && E->canOverflow()) { | |||
3936 | unsigned BitWidth = Value.getBitWidth(); | |||
3937 | APSInt ActualValue(Value.sext(BitWidth + 1), /*IsUnsigned*/false); | |||
3938 | ActualValue.setBit(BitWidth); | |||
3939 | return HandleOverflow(Info, E, ActualValue, SubobjType); | |||
3940 | } | |||
3941 | } | |||
3942 | return true; | |||
3943 | } | |||
3944 | bool found(APFloat &Value, QualType SubobjType) { | |||
3945 | if (!checkConst(SubobjType)) | |||
3946 | return false; | |||
3947 | ||||
3948 | if (Old) *Old = APValue(Value); | |||
3949 | ||||
3950 | APFloat One(Value.getSemantics(), 1); | |||
3951 | if (AccessKind == AK_Increment) | |||
3952 | Value.add(One, APFloat::rmNearestTiesToEven); | |||
3953 | else | |||
3954 | Value.subtract(One, APFloat::rmNearestTiesToEven); | |||
3955 | return true; | |||
3956 | } | |||
3957 | bool foundPointer(APValue &Subobj, QualType SubobjType) { | |||
3958 | if (!checkConst(SubobjType)) | |||
3959 | return false; | |||
3960 | ||||
3961 | QualType PointeeType; | |||
3962 | if (const PointerType *PT = SubobjType->getAs<PointerType>()) | |||
3963 | PointeeType = PT->getPointeeType(); | |||
3964 | else { | |||
3965 | Info.FFDiag(E); | |||
3966 | return false; | |||
3967 | } | |||
3968 | ||||
3969 | LValue LVal; | |||
3970 | LVal.setFrom(Info.Ctx, Subobj); | |||
3971 | if (!HandleLValueArrayAdjustment(Info, E, LVal, PointeeType, | |||
3972 | AccessKind == AK_Increment ? 1 : -1)) | |||
3973 | return false; | |||
3974 | LVal.moveInto(Subobj); | |||
3975 | return true; | |||
3976 | } | |||
3977 | }; | |||
3978 | } // end anonymous namespace | |||
3979 | ||||
3980 | /// Perform an increment or decrement on LVal. | |||
3981 | static bool handleIncDec(EvalInfo &Info, const Expr *E, const LValue &LVal, | |||
3982 | QualType LValType, bool IsIncrement, APValue *Old) { | |||
3983 | if (LVal.Designator.Invalid) | |||
3984 | return false; | |||
3985 | ||||
3986 | if (!Info.getLangOpts().CPlusPlus14) { | |||
3987 | Info.FFDiag(E); | |||
3988 | return false; | |||
3989 | } | |||
3990 | ||||
3991 | AccessKinds AK = IsIncrement ? AK_Increment : AK_Decrement; | |||
3992 | CompleteObject Obj = findCompleteObject(Info, E, AK, LVal, LValType); | |||
3993 | IncDecSubobjectHandler Handler = {Info, cast<UnaryOperator>(E), AK, Old}; | |||
3994 | return Obj && findSubobject(Info, E, Obj, LVal.Designator, Handler); | |||
3995 | } | |||
3996 | ||||
3997 | /// Build an lvalue for the object argument of a member function call. | |||
3998 | static bool EvaluateObjectArgument(EvalInfo &Info, const Expr *Object, | |||
3999 | LValue &This) { | |||
4000 | if (Object->getType()->isPointerType() && Object->isRValue()) | |||
4001 | return EvaluatePointer(Object, This, Info); | |||
4002 | ||||
4003 | if (Object->isGLValue()) | |||
4004 | return EvaluateLValue(Object, This, Info); | |||
4005 | ||||
4006 | if (Object->getType()->isLiteralType(Info.Ctx)) | |||
4007 | return EvaluateTemporary(Object, This, Info); | |||
4008 | ||||
4009 | Info.FFDiag(Object, diag::note_constexpr_nonliteral) << Object->getType(); | |||
4010 | return false; | |||
4011 | } | |||
4012 | ||||
4013 | /// HandleMemberPointerAccess - Evaluate a member access operation and build an | |||
4014 | /// lvalue referring to the result. | |||
4015 | /// | |||
4016 | /// \param Info - Information about the ongoing evaluation. | |||
4017 | /// \param LV - An lvalue referring to the base of the member pointer. | |||
4018 | /// \param RHS - The member pointer expression. | |||
4019 | /// \param IncludeMember - Specifies whether the member itself is included in | |||
4020 | /// the resulting LValue subobject designator. This is not possible when | |||
4021 | /// creating a bound member function. | |||
4022 | /// \return The field or method declaration to which the member pointer refers, | |||
4023 | /// or 0 if evaluation fails. | |||
4024 | static const ValueDecl *HandleMemberPointerAccess(EvalInfo &Info, | |||
4025 | QualType LVType, | |||
4026 | LValue &LV, | |||
4027 | const Expr *RHS, | |||
4028 | bool IncludeMember = true) { | |||
4029 | MemberPtr MemPtr; | |||
4030 | if (!EvaluateMemberPointer(RHS, MemPtr, Info)) | |||
4031 | return nullptr; | |||
4032 | ||||
4033 | // C++11 [expr.mptr.oper]p6: If the second operand is the null pointer to | |||
4034 | // member value, the behavior is undefined. | |||
4035 | if (!MemPtr.getDecl()) { | |||
4036 | // FIXME: Specific diagnostic. | |||
4037 | Info.FFDiag(RHS); | |||
4038 | return nullptr; | |||
4039 | } | |||
4040 | ||||
4041 | if (MemPtr.isDerivedMember()) { | |||
4042 | // This is a member of some derived class. Truncate LV appropriately. | |||
4043 | // The end of the derived-to-base path for the base object must match the | |||
4044 | // derived-to-base path for the member pointer. | |||
4045 | if (LV.Designator.MostDerivedPathLength + MemPtr.Path.size() > | |||
4046 | LV.Designator.Entries.size()) { | |||
4047 | Info.FFDiag(RHS); | |||
4048 | return nullptr; | |||
4049 | } | |||
4050 | unsigned PathLengthToMember = | |||
4051 | LV.Designator.Entries.size() - MemPtr.Path.size(); | |||
4052 | for (unsigned I = 0, N = MemPtr.Path.size(); I != N; ++I) { | |||
4053 | const CXXRecordDecl *LVDecl = getAsBaseClass( | |||
4054 | LV.Designator.Entries[PathLengthToMember + I]); | |||
4055 | const CXXRecordDecl *MPDecl = MemPtr.Path[I]; | |||
4056 | if (LVDecl->getCanonicalDecl() != MPDecl->getCanonicalDecl()) { | |||
4057 | Info.FFDiag(RHS); | |||
4058 | return nullptr; | |||
4059 | } | |||
4060 | } | |||
4061 | ||||
4062 | // Truncate the lvalue to the appropriate derived class. | |||
4063 | if (!CastToDerivedClass(Info, RHS, LV, MemPtr.getContainingRecord(), | |||
4064 | PathLengthToMember)) | |||
4065 | return nullptr; | |||
4066 | } else if (!MemPtr.Path.empty()) { | |||
4067 | // Extend the LValue path with the member pointer's path. | |||
4068 | LV.Designator.Entries.reserve(LV.Designator.Entries.size() + | |||
4069 | MemPtr.Path.size() + IncludeMember); | |||
4070 | ||||
4071 | // Walk down to the appropriate base class. | |||
4072 | if (const PointerType *PT = LVType->getAs<PointerType>()) | |||
4073 | LVType = PT->getPointeeType(); | |||
4074 | const CXXRecordDecl *RD = LVType->getAsCXXRecordDecl(); | |||
4075 | assert(RD && "member pointer access on non-class-type expression")((RD && "member pointer access on non-class-type expression" ) ? static_cast<void> (0) : __assert_fail ("RD && \"member pointer access on non-class-type expression\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 4075, __PRETTY_FUNCTION__)); | |||
4076 | // The first class in the path is that of the lvalue. | |||
4077 | for (unsigned I = 1, N = MemPtr.Path.size(); I != N; ++I) { | |||
4078 | const CXXRecordDecl *Base = MemPtr.Path[N - I - 1]; | |||
4079 | if (!HandleLValueDirectBase(Info, RHS, LV, RD, Base)) | |||
4080 | return nullptr; | |||
4081 | RD = Base; | |||
4082 | } | |||
4083 | // Finally cast to the class containing the member. | |||
4084 | if (!HandleLValueDirectBase(Info, RHS, LV, RD, | |||
4085 | MemPtr.getContainingRecord())) | |||
4086 | return nullptr; | |||
4087 | } | |||
4088 | ||||
4089 | // Add the member. Note that we cannot build bound member functions here. | |||
4090 | if (IncludeMember) { | |||
4091 | if (const FieldDecl *FD = dyn_cast<FieldDecl>(MemPtr.getDecl())) { | |||
4092 | if (!HandleLValueMember(Info, RHS, LV, FD)) | |||
4093 | return nullptr; | |||
4094 | } else if (const IndirectFieldDecl *IFD = | |||
4095 | dyn_cast<IndirectFieldDecl>(MemPtr.getDecl())) { | |||
4096 | if (!HandleLValueIndirectMember(Info, RHS, LV, IFD)) | |||
4097 | return nullptr; | |||
4098 | } else { | |||
4099 | llvm_unreachable("can't construct reference to bound member function")::llvm::llvm_unreachable_internal("can't construct reference to bound member function" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 4099); | |||
4100 | } | |||
4101 | } | |||
4102 | ||||
4103 | return MemPtr.getDecl(); | |||
4104 | } | |||
4105 | ||||
4106 | static const ValueDecl *HandleMemberPointerAccess(EvalInfo &Info, | |||
4107 | const BinaryOperator *BO, | |||
4108 | LValue &LV, | |||
4109 | bool IncludeMember = true) { | |||
4110 | assert(BO->getOpcode() == BO_PtrMemD || BO->getOpcode() == BO_PtrMemI)((BO->getOpcode() == BO_PtrMemD || BO->getOpcode() == BO_PtrMemI ) ? static_cast<void> (0) : __assert_fail ("BO->getOpcode() == BO_PtrMemD || BO->getOpcode() == BO_PtrMemI" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 4110, __PRETTY_FUNCTION__)); | |||
4111 | ||||
4112 | if (!EvaluateObjectArgument(Info, BO->getLHS(), LV)) { | |||
4113 | if (Info.noteFailure()) { | |||
4114 | MemberPtr MemPtr; | |||
4115 | EvaluateMemberPointer(BO->getRHS(), MemPtr, Info); | |||
4116 | } | |||
4117 | return nullptr; | |||
4118 | } | |||
4119 | ||||
4120 | return HandleMemberPointerAccess(Info, BO->getLHS()->getType(), LV, | |||
4121 | BO->getRHS(), IncludeMember); | |||
4122 | } | |||
4123 | ||||
4124 | /// HandleBaseToDerivedCast - Apply the given base-to-derived cast operation on | |||
4125 | /// the provided lvalue, which currently refers to the base object. | |||
4126 | static bool HandleBaseToDerivedCast(EvalInfo &Info, const CastExpr *E, | |||
4127 | LValue &Result) { | |||
4128 | SubobjectDesignator &D = Result.Designator; | |||
4129 | if (D.Invalid || !Result.checkNullPointer(Info, E, CSK_Derived)) | |||
4130 | return false; | |||
4131 | ||||
4132 | QualType TargetQT = E->getType(); | |||
4133 | if (const PointerType *PT = TargetQT->getAs<PointerType>()) | |||
4134 | TargetQT = PT->getPointeeType(); | |||
4135 | ||||
4136 | // Check this cast lands within the final derived-to-base subobject path. | |||
4137 | if (D.MostDerivedPathLength + E->path_size() > D.Entries.size()) { | |||
4138 | Info.CCEDiag(E, diag::note_constexpr_invalid_downcast) | |||
4139 | << D.MostDerivedType << TargetQT; | |||
4140 | return false; | |||
4141 | } | |||
4142 | ||||
4143 | // Check the type of the final cast. We don't need to check the path, | |||
4144 | // since a cast can only be formed if the path is unique. | |||
4145 | unsigned NewEntriesSize = D.Entries.size() - E->path_size(); | |||
4146 | const CXXRecordDecl *TargetType = TargetQT->getAsCXXRecordDecl(); | |||
4147 | const CXXRecordDecl *FinalType; | |||
4148 | if (NewEntriesSize == D.MostDerivedPathLength) | |||
4149 | FinalType = D.MostDerivedType->getAsCXXRecordDecl(); | |||
4150 | else | |||
4151 | FinalType = getAsBaseClass(D.Entries[NewEntriesSize - 1]); | |||
4152 | if (FinalType->getCanonicalDecl() != TargetType->getCanonicalDecl()) { | |||
4153 | Info.CCEDiag(E, diag::note_constexpr_invalid_downcast) | |||
4154 | << D.MostDerivedType << TargetQT; | |||
4155 | return false; | |||
4156 | } | |||
4157 | ||||
4158 | // Truncate the lvalue to the appropriate derived class. | |||
4159 | return CastToDerivedClass(Info, E, Result, TargetType, NewEntriesSize); | |||
4160 | } | |||
4161 | ||||
4162 | /// Get the value to use for a default-initialized object of type T. | |||
4163 | static APValue getDefaultInitValue(QualType T) { | |||
4164 | if (auto *RD = T->getAsCXXRecordDecl()) { | |||
4165 | if (RD->isUnion()) | |||
4166 | return APValue((const FieldDecl*)nullptr); | |||
4167 | ||||
4168 | APValue Struct(APValue::UninitStruct(), RD->getNumBases(), | |||
4169 | std::distance(RD->field_begin(), RD->field_end())); | |||
4170 | ||||
4171 | unsigned Index = 0; | |||
4172 | for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(), | |||
4173 | End = RD->bases_end(); I != End; ++I, ++Index) | |||
4174 | Struct.getStructBase(Index) = getDefaultInitValue(I->getType()); | |||
4175 | ||||
4176 | for (const auto *I : RD->fields()) { | |||
4177 | if (I->isUnnamedBitfield()) | |||
4178 | continue; | |||
4179 | Struct.getStructField(I->getFieldIndex()) = | |||
4180 | getDefaultInitValue(I->getType()); | |||
4181 | } | |||
4182 | return Struct; | |||
4183 | } | |||
4184 | ||||
4185 | if (auto *AT = | |||
4186 | dyn_cast_or_null<ConstantArrayType>(T->getAsArrayTypeUnsafe())) { | |||
4187 | APValue Array(APValue::UninitArray(), 0, AT->getSize().getZExtValue()); | |||
4188 | if (Array.hasArrayFiller()) | |||
4189 | Array.getArrayFiller() = getDefaultInitValue(AT->getElementType()); | |||
4190 | return Array; | |||
4191 | } | |||
4192 | ||||
4193 | return APValue::IndeterminateValue(); | |||
4194 | } | |||
4195 | ||||
4196 | namespace { | |||
4197 | enum EvalStmtResult { | |||
4198 | /// Evaluation failed. | |||
4199 | ESR_Failed, | |||
4200 | /// Hit a 'return' statement. | |||
4201 | ESR_Returned, | |||
4202 | /// Evaluation succeeded. | |||
4203 | ESR_Succeeded, | |||
4204 | /// Hit a 'continue' statement. | |||
4205 | ESR_Continue, | |||
4206 | /// Hit a 'break' statement. | |||
4207 | ESR_Break, | |||
4208 | /// Still scanning for 'case' or 'default' statement. | |||
4209 | ESR_CaseNotFound | |||
4210 | }; | |||
4211 | } | |||
4212 | ||||
4213 | static bool EvaluateVarDecl(EvalInfo &Info, const VarDecl *VD) { | |||
4214 | // We don't need to evaluate the initializer for a static local. | |||
4215 | if (!VD->hasLocalStorage()) | |||
4216 | return true; | |||
4217 | ||||
4218 | LValue Result; | |||
4219 | APValue &Val = | |||
4220 | Info.CurrentCall->createTemporary(VD, VD->getType(), true, Result); | |||
4221 | ||||
4222 | const Expr *InitE = VD->getInit(); | |||
4223 | if (!InitE) { | |||
4224 | Val = getDefaultInitValue(VD->getType()); | |||
4225 | return true; | |||
4226 | } | |||
4227 | ||||
4228 | if (InitE->isValueDependent()) | |||
4229 | return false; | |||
4230 | ||||
4231 | if (!EvaluateInPlace(Val, Info, Result, InitE)) { | |||
4232 | // Wipe out any partially-computed value, to allow tracking that this | |||
4233 | // evaluation failed. | |||
4234 | Val = APValue(); | |||
4235 | return false; | |||
4236 | } | |||
4237 | ||||
4238 | return true; | |||
4239 | } | |||
4240 | ||||
4241 | static bool EvaluateDecl(EvalInfo &Info, const Decl *D) { | |||
4242 | bool OK = true; | |||
4243 | ||||
4244 | if (const VarDecl *VD = dyn_cast<VarDecl>(D)) | |||
4245 | OK &= EvaluateVarDecl(Info, VD); | |||
4246 | ||||
4247 | if (const DecompositionDecl *DD = dyn_cast<DecompositionDecl>(D)) | |||
4248 | for (auto *BD : DD->bindings()) | |||
4249 | if (auto *VD = BD->getHoldingVar()) | |||
4250 | OK &= EvaluateDecl(Info, VD); | |||
4251 | ||||
4252 | return OK; | |||
4253 | } | |||
4254 | ||||
4255 | ||||
4256 | /// Evaluate a condition (either a variable declaration or an expression). | |||
4257 | static bool EvaluateCond(EvalInfo &Info, const VarDecl *CondDecl, | |||
4258 | const Expr *Cond, bool &Result) { | |||
4259 | FullExpressionRAII Scope(Info); | |||
4260 | if (CondDecl && !EvaluateDecl(Info, CondDecl)) | |||
4261 | return false; | |||
4262 | if (!EvaluateAsBooleanCondition(Cond, Result, Info)) | |||
4263 | return false; | |||
4264 | return Scope.destroy(); | |||
4265 | } | |||
4266 | ||||
4267 | namespace { | |||
4268 | /// A location where the result (returned value) of evaluating a | |||
4269 | /// statement should be stored. | |||
4270 | struct StmtResult { | |||
4271 | /// The APValue that should be filled in with the returned value. | |||
4272 | APValue &Value; | |||
4273 | /// The location containing the result, if any (used to support RVO). | |||
4274 | const LValue *Slot; | |||
4275 | }; | |||
4276 | ||||
4277 | struct TempVersionRAII { | |||
4278 | CallStackFrame &Frame; | |||
4279 | ||||
4280 | TempVersionRAII(CallStackFrame &Frame) : Frame(Frame) { | |||
4281 | Frame.pushTempVersion(); | |||
4282 | } | |||
4283 | ||||
4284 | ~TempVersionRAII() { | |||
4285 | Frame.popTempVersion(); | |||
4286 | } | |||
4287 | }; | |||
4288 | ||||
4289 | } | |||
4290 | ||||
4291 | static EvalStmtResult EvaluateStmt(StmtResult &Result, EvalInfo &Info, | |||
4292 | const Stmt *S, | |||
4293 | const SwitchCase *SC = nullptr); | |||
4294 | ||||
4295 | /// Evaluate the body of a loop, and translate the result as appropriate. | |||
4296 | static EvalStmtResult EvaluateLoopBody(StmtResult &Result, EvalInfo &Info, | |||
4297 | const Stmt *Body, | |||
4298 | const SwitchCase *Case = nullptr) { | |||
4299 | BlockScopeRAII Scope(Info); | |||
4300 | ||||
4301 | EvalStmtResult ESR = EvaluateStmt(Result, Info, Body, Case); | |||
4302 | if (ESR != ESR_Failed && ESR != ESR_CaseNotFound && !Scope.destroy()) | |||
4303 | ESR = ESR_Failed; | |||
4304 | ||||
4305 | switch (ESR) { | |||
4306 | case ESR_Break: | |||
4307 | return ESR_Succeeded; | |||
4308 | case ESR_Succeeded: | |||
4309 | case ESR_Continue: | |||
4310 | return ESR_Continue; | |||
4311 | case ESR_Failed: | |||
4312 | case ESR_Returned: | |||
4313 | case ESR_CaseNotFound: | |||
4314 | return ESR; | |||
4315 | } | |||
4316 | llvm_unreachable("Invalid EvalStmtResult!")::llvm::llvm_unreachable_internal("Invalid EvalStmtResult!", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 4316); | |||
4317 | } | |||
4318 | ||||
4319 | /// Evaluate a switch statement. | |||
4320 | static EvalStmtResult EvaluateSwitch(StmtResult &Result, EvalInfo &Info, | |||
4321 | const SwitchStmt *SS) { | |||
4322 | BlockScopeRAII Scope(Info); | |||
4323 | ||||
4324 | // Evaluate the switch condition. | |||
4325 | APSInt Value; | |||
4326 | { | |||
4327 | if (const Stmt *Init = SS->getInit()) { | |||
4328 | EvalStmtResult ESR = EvaluateStmt(Result, Info, Init); | |||
4329 | if (ESR != ESR_Succeeded) { | |||
4330 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
4331 | ESR = ESR_Failed; | |||
4332 | return ESR; | |||
4333 | } | |||
4334 | } | |||
4335 | ||||
4336 | FullExpressionRAII CondScope(Info); | |||
4337 | if (SS->getConditionVariable() && | |||
4338 | !EvaluateDecl(Info, SS->getConditionVariable())) | |||
4339 | return ESR_Failed; | |||
4340 | if (!EvaluateInteger(SS->getCond(), Value, Info)) | |||
4341 | return ESR_Failed; | |||
4342 | if (!CondScope.destroy()) | |||
4343 | return ESR_Failed; | |||
4344 | } | |||
4345 | ||||
4346 | // Find the switch case corresponding to the value of the condition. | |||
4347 | // FIXME: Cache this lookup. | |||
4348 | const SwitchCase *Found = nullptr; | |||
4349 | for (const SwitchCase *SC = SS->getSwitchCaseList(); SC; | |||
4350 | SC = SC->getNextSwitchCase()) { | |||
4351 | if (isa<DefaultStmt>(SC)) { | |||
4352 | Found = SC; | |||
4353 | continue; | |||
4354 | } | |||
4355 | ||||
4356 | const CaseStmt *CS = cast<CaseStmt>(SC); | |||
4357 | APSInt LHS = CS->getLHS()->EvaluateKnownConstInt(Info.Ctx); | |||
4358 | APSInt RHS = CS->getRHS() ? CS->getRHS()->EvaluateKnownConstInt(Info.Ctx) | |||
4359 | : LHS; | |||
4360 | if (LHS <= Value && Value <= RHS) { | |||
4361 | Found = SC; | |||
4362 | break; | |||
4363 | } | |||
4364 | } | |||
4365 | ||||
4366 | if (!Found) | |||
4367 | return Scope.destroy() ? ESR_Failed : ESR_Succeeded; | |||
4368 | ||||
4369 | // Search the switch body for the switch case and evaluate it from there. | |||
4370 | EvalStmtResult ESR = EvaluateStmt(Result, Info, SS->getBody(), Found); | |||
4371 | if (ESR != ESR_Failed && ESR != ESR_CaseNotFound && !Scope.destroy()) | |||
4372 | return ESR_Failed; | |||
4373 | ||||
4374 | switch (ESR) { | |||
4375 | case ESR_Break: | |||
4376 | return ESR_Succeeded; | |||
4377 | case ESR_Succeeded: | |||
4378 | case ESR_Continue: | |||
4379 | case ESR_Failed: | |||
4380 | case ESR_Returned: | |||
4381 | return ESR; | |||
4382 | case ESR_CaseNotFound: | |||
4383 | // This can only happen if the switch case is nested within a statement | |||
4384 | // expression. We have no intention of supporting that. | |||
4385 | Info.FFDiag(Found->getBeginLoc(), | |||
4386 | diag::note_constexpr_stmt_expr_unsupported); | |||
4387 | return ESR_Failed; | |||
4388 | } | |||
4389 | llvm_unreachable("Invalid EvalStmtResult!")::llvm::llvm_unreachable_internal("Invalid EvalStmtResult!", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 4389); | |||
4390 | } | |||
4391 | ||||
4392 | // Evaluate a statement. | |||
4393 | static EvalStmtResult EvaluateStmt(StmtResult &Result, EvalInfo &Info, | |||
4394 | const Stmt *S, const SwitchCase *Case) { | |||
4395 | if (!Info.nextStep(S)) | |||
4396 | return ESR_Failed; | |||
4397 | ||||
4398 | // If we're hunting down a 'case' or 'default' label, recurse through | |||
4399 | // substatements until we hit the label. | |||
4400 | if (Case) { | |||
4401 | switch (S->getStmtClass()) { | |||
4402 | case Stmt::CompoundStmtClass: | |||
4403 | // FIXME: Precompute which substatement of a compound statement we | |||
4404 | // would jump to, and go straight there rather than performing a | |||
4405 | // linear scan each time. | |||
4406 | case Stmt::LabelStmtClass: | |||
4407 | case Stmt::AttributedStmtClass: | |||
4408 | case Stmt::DoStmtClass: | |||
4409 | break; | |||
4410 | ||||
4411 | case Stmt::CaseStmtClass: | |||
4412 | case Stmt::DefaultStmtClass: | |||
4413 | if (Case == S) | |||
4414 | Case = nullptr; | |||
4415 | break; | |||
4416 | ||||
4417 | case Stmt::IfStmtClass: { | |||
4418 | // FIXME: Precompute which side of an 'if' we would jump to, and go | |||
4419 | // straight there rather than scanning both sides. | |||
4420 | const IfStmt *IS = cast<IfStmt>(S); | |||
4421 | ||||
4422 | // Wrap the evaluation in a block scope, in case it's a DeclStmt | |||
4423 | // preceded by our switch label. | |||
4424 | BlockScopeRAII Scope(Info); | |||
4425 | ||||
4426 | // Step into the init statement in case it brings an (uninitialized) | |||
4427 | // variable into scope. | |||
4428 | if (const Stmt *Init = IS->getInit()) { | |||
4429 | EvalStmtResult ESR = EvaluateStmt(Result, Info, Init, Case); | |||
4430 | if (ESR != ESR_CaseNotFound) { | |||
4431 | assert(ESR != ESR_Succeeded)((ESR != ESR_Succeeded) ? static_cast<void> (0) : __assert_fail ("ESR != ESR_Succeeded", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 4431, __PRETTY_FUNCTION__)); | |||
4432 | return ESR; | |||
4433 | } | |||
4434 | } | |||
4435 | ||||
4436 | // Condition variable must be initialized if it exists. | |||
4437 | // FIXME: We can skip evaluating the body if there's a condition | |||
4438 | // variable, as there can't be any case labels within it. | |||
4439 | // (The same is true for 'for' statements.) | |||
4440 | ||||
4441 | EvalStmtResult ESR = EvaluateStmt(Result, Info, IS->getThen(), Case); | |||
4442 | if (ESR == ESR_Failed) | |||
4443 | return ESR; | |||
4444 | if (ESR != ESR_CaseNotFound) | |||
4445 | return Scope.destroy() ? ESR : ESR_Failed; | |||
4446 | if (!IS->getElse()) | |||
4447 | return ESR_CaseNotFound; | |||
4448 | ||||
4449 | ESR = EvaluateStmt(Result, Info, IS->getElse(), Case); | |||
4450 | if (ESR == ESR_Failed) | |||
4451 | return ESR; | |||
4452 | if (ESR != ESR_CaseNotFound) | |||
4453 | return Scope.destroy() ? ESR : ESR_Failed; | |||
4454 | return ESR_CaseNotFound; | |||
4455 | } | |||
4456 | ||||
4457 | case Stmt::WhileStmtClass: { | |||
4458 | EvalStmtResult ESR = | |||
4459 | EvaluateLoopBody(Result, Info, cast<WhileStmt>(S)->getBody(), Case); | |||
4460 | if (ESR != ESR_Continue) | |||
4461 | return ESR; | |||
4462 | break; | |||
4463 | } | |||
4464 | ||||
4465 | case Stmt::ForStmtClass: { | |||
4466 | const ForStmt *FS = cast<ForStmt>(S); | |||
4467 | BlockScopeRAII Scope(Info); | |||
4468 | ||||
4469 | // Step into the init statement in case it brings an (uninitialized) | |||
4470 | // variable into scope. | |||
4471 | if (const Stmt *Init = FS->getInit()) { | |||
4472 | EvalStmtResult ESR = EvaluateStmt(Result, Info, Init, Case); | |||
4473 | if (ESR != ESR_CaseNotFound) { | |||
4474 | assert(ESR != ESR_Succeeded)((ESR != ESR_Succeeded) ? static_cast<void> (0) : __assert_fail ("ESR != ESR_Succeeded", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 4474, __PRETTY_FUNCTION__)); | |||
4475 | return ESR; | |||
4476 | } | |||
4477 | } | |||
4478 | ||||
4479 | EvalStmtResult ESR = | |||
4480 | EvaluateLoopBody(Result, Info, FS->getBody(), Case); | |||
4481 | if (ESR != ESR_Continue) | |||
4482 | return ESR; | |||
4483 | if (FS->getInc()) { | |||
4484 | FullExpressionRAII IncScope(Info); | |||
4485 | if (!EvaluateIgnoredValue(Info, FS->getInc()) || !IncScope.destroy()) | |||
4486 | return ESR_Failed; | |||
4487 | } | |||
4488 | break; | |||
4489 | } | |||
4490 | ||||
4491 | case Stmt::DeclStmtClass: { | |||
4492 | // Start the lifetime of any uninitialized variables we encounter. They | |||
4493 | // might be used by the selected branch of the switch. | |||
4494 | const DeclStmt *DS = cast<DeclStmt>(S); | |||
4495 | for (const auto *D : DS->decls()) { | |||
4496 | if (const auto *VD = dyn_cast<VarDecl>(D)) { | |||
4497 | if (VD->hasLocalStorage() && !VD->getInit()) | |||
4498 | if (!EvaluateVarDecl(Info, VD)) | |||
4499 | return ESR_Failed; | |||
4500 | // FIXME: If the variable has initialization that can't be jumped | |||
4501 | // over, bail out of any immediately-surrounding compound-statement | |||
4502 | // too. There can't be any case labels here. | |||
4503 | } | |||
4504 | } | |||
4505 | return ESR_CaseNotFound; | |||
4506 | } | |||
4507 | ||||
4508 | default: | |||
4509 | return ESR_CaseNotFound; | |||
4510 | } | |||
4511 | } | |||
4512 | ||||
4513 | switch (S->getStmtClass()) { | |||
4514 | default: | |||
4515 | if (const Expr *E = dyn_cast<Expr>(S)) { | |||
4516 | // Don't bother evaluating beyond an expression-statement which couldn't | |||
4517 | // be evaluated. | |||
4518 | // FIXME: Do we need the FullExpressionRAII object here? | |||
4519 | // VisitExprWithCleanups should create one when necessary. | |||
4520 | FullExpressionRAII Scope(Info); | |||
4521 | if (!EvaluateIgnoredValue(Info, E) || !Scope.destroy()) | |||
4522 | return ESR_Failed; | |||
4523 | return ESR_Succeeded; | |||
4524 | } | |||
4525 | ||||
4526 | Info.FFDiag(S->getBeginLoc()); | |||
4527 | return ESR_Failed; | |||
4528 | ||||
4529 | case Stmt::NullStmtClass: | |||
4530 | return ESR_Succeeded; | |||
4531 | ||||
4532 | case Stmt::DeclStmtClass: { | |||
4533 | const DeclStmt *DS = cast<DeclStmt>(S); | |||
4534 | for (const auto *D : DS->decls()) { | |||
4535 | // Each declaration initialization is its own full-expression. | |||
4536 | FullExpressionRAII Scope(Info); | |||
4537 | if (!EvaluateDecl(Info, D) && !Info.noteFailure()) | |||
4538 | return ESR_Failed; | |||
4539 | if (!Scope.destroy()) | |||
4540 | return ESR_Failed; | |||
4541 | } | |||
4542 | return ESR_Succeeded; | |||
4543 | } | |||
4544 | ||||
4545 | case Stmt::ReturnStmtClass: { | |||
4546 | const Expr *RetExpr = cast<ReturnStmt>(S)->getRetValue(); | |||
4547 | FullExpressionRAII Scope(Info); | |||
4548 | if (RetExpr && | |||
4549 | !(Result.Slot | |||
4550 | ? EvaluateInPlace(Result.Value, Info, *Result.Slot, RetExpr) | |||
4551 | : Evaluate(Result.Value, Info, RetExpr))) | |||
4552 | return ESR_Failed; | |||
4553 | return Scope.destroy() ? ESR_Returned : ESR_Failed; | |||
4554 | } | |||
4555 | ||||
4556 | case Stmt::CompoundStmtClass: { | |||
4557 | BlockScopeRAII Scope(Info); | |||
4558 | ||||
4559 | const CompoundStmt *CS = cast<CompoundStmt>(S); | |||
4560 | for (const auto *BI : CS->body()) { | |||
4561 | EvalStmtResult ESR = EvaluateStmt(Result, Info, BI, Case); | |||
4562 | if (ESR == ESR_Succeeded) | |||
4563 | Case = nullptr; | |||
4564 | else if (ESR != ESR_CaseNotFound) { | |||
4565 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
4566 | return ESR_Failed; | |||
4567 | return ESR; | |||
4568 | } | |||
4569 | } | |||
4570 | if (Case) | |||
4571 | return ESR_CaseNotFound; | |||
4572 | return Scope.destroy() ? ESR_Succeeded : ESR_Failed; | |||
4573 | } | |||
4574 | ||||
4575 | case Stmt::IfStmtClass: { | |||
4576 | const IfStmt *IS = cast<IfStmt>(S); | |||
4577 | ||||
4578 | // Evaluate the condition, as either a var decl or as an expression. | |||
4579 | BlockScopeRAII Scope(Info); | |||
4580 | if (const Stmt *Init = IS->getInit()) { | |||
4581 | EvalStmtResult ESR = EvaluateStmt(Result, Info, Init); | |||
4582 | if (ESR != ESR_Succeeded) { | |||
4583 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
4584 | return ESR_Failed; | |||
4585 | return ESR; | |||
4586 | } | |||
4587 | } | |||
4588 | bool Cond; | |||
4589 | if (!EvaluateCond(Info, IS->getConditionVariable(), IS->getCond(), Cond)) | |||
4590 | return ESR_Failed; | |||
4591 | ||||
4592 | if (const Stmt *SubStmt = Cond ? IS->getThen() : IS->getElse()) { | |||
4593 | EvalStmtResult ESR = EvaluateStmt(Result, Info, SubStmt); | |||
4594 | if (ESR != ESR_Succeeded) { | |||
4595 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
4596 | return ESR_Failed; | |||
4597 | return ESR; | |||
4598 | } | |||
4599 | } | |||
4600 | return Scope.destroy() ? ESR_Succeeded : ESR_Failed; | |||
4601 | } | |||
4602 | ||||
4603 | case Stmt::WhileStmtClass: { | |||
4604 | const WhileStmt *WS = cast<WhileStmt>(S); | |||
4605 | while (true) { | |||
4606 | BlockScopeRAII Scope(Info); | |||
4607 | bool Continue; | |||
4608 | if (!EvaluateCond(Info, WS->getConditionVariable(), WS->getCond(), | |||
4609 | Continue)) | |||
4610 | return ESR_Failed; | |||
4611 | if (!Continue) | |||
4612 | break; | |||
4613 | ||||
4614 | EvalStmtResult ESR = EvaluateLoopBody(Result, Info, WS->getBody()); | |||
4615 | if (ESR != ESR_Continue) { | |||
4616 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
4617 | return ESR_Failed; | |||
4618 | return ESR; | |||
4619 | } | |||
4620 | if (!Scope.destroy()) | |||
4621 | return ESR_Failed; | |||
4622 | } | |||
4623 | return ESR_Succeeded; | |||
4624 | } | |||
4625 | ||||
4626 | case Stmt::DoStmtClass: { | |||
4627 | const DoStmt *DS = cast<DoStmt>(S); | |||
4628 | bool Continue; | |||
4629 | do { | |||
4630 | EvalStmtResult ESR = EvaluateLoopBody(Result, Info, DS->getBody(), Case); | |||
4631 | if (ESR != ESR_Continue) | |||
4632 | return ESR; | |||
4633 | Case = nullptr; | |||
4634 | ||||
4635 | FullExpressionRAII CondScope(Info); | |||
4636 | if (!EvaluateAsBooleanCondition(DS->getCond(), Continue, Info) || | |||
4637 | !CondScope.destroy()) | |||
4638 | return ESR_Failed; | |||
4639 | } while (Continue); | |||
4640 | return ESR_Succeeded; | |||
4641 | } | |||
4642 | ||||
4643 | case Stmt::ForStmtClass: { | |||
4644 | const ForStmt *FS = cast<ForStmt>(S); | |||
4645 | BlockScopeRAII ForScope(Info); | |||
4646 | if (FS->getInit()) { | |||
4647 | EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getInit()); | |||
4648 | if (ESR != ESR_Succeeded) { | |||
4649 | if (ESR != ESR_Failed && !ForScope.destroy()) | |||
4650 | return ESR_Failed; | |||
4651 | return ESR; | |||
4652 | } | |||
4653 | } | |||
4654 | while (true) { | |||
4655 | BlockScopeRAII IterScope(Info); | |||
4656 | bool Continue = true; | |||
4657 | if (FS->getCond() && !EvaluateCond(Info, FS->getConditionVariable(), | |||
4658 | FS->getCond(), Continue)) | |||
4659 | return ESR_Failed; | |||
4660 | if (!Continue) | |||
4661 | break; | |||
4662 | ||||
4663 | EvalStmtResult ESR = EvaluateLoopBody(Result, Info, FS->getBody()); | |||
4664 | if (ESR != ESR_Continue) { | |||
4665 | if (ESR != ESR_Failed && (!IterScope.destroy() || !ForScope.destroy())) | |||
4666 | return ESR_Failed; | |||
4667 | return ESR; | |||
4668 | } | |||
4669 | ||||
4670 | if (FS->getInc()) { | |||
4671 | FullExpressionRAII IncScope(Info); | |||
4672 | if (!EvaluateIgnoredValue(Info, FS->getInc()) || !IncScope.destroy()) | |||
4673 | return ESR_Failed; | |||
4674 | } | |||
4675 | ||||
4676 | if (!IterScope.destroy()) | |||
4677 | return ESR_Failed; | |||
4678 | } | |||
4679 | return ForScope.destroy() ? ESR_Succeeded : ESR_Failed; | |||
4680 | } | |||
4681 | ||||
4682 | case Stmt::CXXForRangeStmtClass: { | |||
4683 | const CXXForRangeStmt *FS = cast<CXXForRangeStmt>(S); | |||
4684 | BlockScopeRAII Scope(Info); | |||
4685 | ||||
4686 | // Evaluate the init-statement if present. | |||
4687 | if (FS->getInit()) { | |||
4688 | EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getInit()); | |||
4689 | if (ESR != ESR_Succeeded) { | |||
4690 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
4691 | return ESR_Failed; | |||
4692 | return ESR; | |||
4693 | } | |||
4694 | } | |||
4695 | ||||
4696 | // Initialize the __range variable. | |||
4697 | EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getRangeStmt()); | |||
4698 | if (ESR != ESR_Succeeded) { | |||
4699 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
4700 | return ESR_Failed; | |||
4701 | return ESR; | |||
4702 | } | |||
4703 | ||||
4704 | // Create the __begin and __end iterators. | |||
4705 | ESR = EvaluateStmt(Result, Info, FS->getBeginStmt()); | |||
4706 | if (ESR != ESR_Succeeded) { | |||
4707 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
4708 | return ESR_Failed; | |||
4709 | return ESR; | |||
4710 | } | |||
4711 | ESR = EvaluateStmt(Result, Info, FS->getEndStmt()); | |||
4712 | if (ESR != ESR_Succeeded) { | |||
4713 | if (ESR != ESR_Failed && !Scope.destroy()) | |||
4714 | return ESR_Failed; | |||
4715 | return ESR; | |||
4716 | } | |||
4717 | ||||
4718 | while (true) { | |||
4719 | // Condition: __begin != __end. | |||
4720 | { | |||
4721 | bool Continue = true; | |||
4722 | FullExpressionRAII CondExpr(Info); | |||
4723 | if (!EvaluateAsBooleanCondition(FS->getCond(), Continue, Info)) | |||
4724 | return ESR_Failed; | |||
4725 | if (!Continue) | |||
4726 | break; | |||
4727 | } | |||
4728 | ||||
4729 | // User's variable declaration, initialized by *__begin. | |||
4730 | BlockScopeRAII InnerScope(Info); | |||
4731 | ESR = EvaluateStmt(Result, Info, FS->getLoopVarStmt()); | |||
4732 | if (ESR != ESR_Succeeded) { | |||
4733 | if (ESR != ESR_Failed && (!InnerScope.destroy() || !Scope.destroy())) | |||
4734 | return ESR_Failed; | |||
4735 | return ESR; | |||
4736 | } | |||
4737 | ||||
4738 | // Loop body. | |||
4739 | ESR = EvaluateLoopBody(Result, Info, FS->getBody()); | |||
4740 | if (ESR != ESR_Continue) { | |||
4741 | if (ESR != ESR_Failed && (!InnerScope.destroy() || !Scope.destroy())) | |||
4742 | return ESR_Failed; | |||
4743 | return ESR; | |||
4744 | } | |||
4745 | ||||
4746 | // Increment: ++__begin | |||
4747 | if (!EvaluateIgnoredValue(Info, FS->getInc())) | |||
4748 | return ESR_Failed; | |||
4749 | ||||
4750 | if (!InnerScope.destroy()) | |||
4751 | return ESR_Failed; | |||
4752 | } | |||
4753 | ||||
4754 | return Scope.destroy() ? ESR_Succeeded : ESR_Failed; | |||
4755 | } | |||
4756 | ||||
4757 | case Stmt::SwitchStmtClass: | |||
4758 | return EvaluateSwitch(Result, Info, cast<SwitchStmt>(S)); | |||
4759 | ||||
4760 | case Stmt::ContinueStmtClass: | |||
4761 | return ESR_Continue; | |||
4762 | ||||
4763 | case Stmt::BreakStmtClass: | |||
4764 | return ESR_Break; | |||
4765 | ||||
4766 | case Stmt::LabelStmtClass: | |||
4767 | return EvaluateStmt(Result, Info, cast<LabelStmt>(S)->getSubStmt(), Case); | |||
4768 | ||||
4769 | case Stmt::AttributedStmtClass: | |||
4770 | // As a general principle, C++11 attributes can be ignored without | |||
4771 | // any semantic impact. | |||
4772 | return EvaluateStmt(Result, Info, cast<AttributedStmt>(S)->getSubStmt(), | |||
4773 | Case); | |||
4774 | ||||
4775 | case Stmt::CaseStmtClass: | |||
4776 | case Stmt::DefaultStmtClass: | |||
4777 | return EvaluateStmt(Result, Info, cast<SwitchCase>(S)->getSubStmt(), Case); | |||
4778 | case Stmt::CXXTryStmtClass: | |||
4779 | // Evaluate try blocks by evaluating all sub statements. | |||
4780 | return EvaluateStmt(Result, Info, cast<CXXTryStmt>(S)->getTryBlock(), Case); | |||
4781 | } | |||
4782 | } | |||
4783 | ||||
4784 | /// CheckTrivialDefaultConstructor - Check whether a constructor is a trivial | |||
4785 | /// default constructor. If so, we'll fold it whether or not it's marked as | |||
4786 | /// constexpr. If it is marked as constexpr, we will never implicitly define it, | |||
4787 | /// so we need special handling. | |||
4788 | static bool CheckTrivialDefaultConstructor(EvalInfo &Info, SourceLocation Loc, | |||
4789 | const CXXConstructorDecl *CD, | |||
4790 | bool IsValueInitialization) { | |||
4791 | if (!CD->isTrivial() || !CD->isDefaultConstructor()) | |||
4792 | return false; | |||
4793 | ||||
4794 | // Value-initialization does not call a trivial default constructor, so such a | |||
4795 | // call is a core constant expression whether or not the constructor is | |||
4796 | // constexpr. | |||
4797 | if (!CD->isConstexpr() && !IsValueInitialization) { | |||
4798 | if (Info.getLangOpts().CPlusPlus11) { | |||
4799 | // FIXME: If DiagDecl is an implicitly-declared special member function, | |||
4800 | // we should be much more explicit about why it's not constexpr. | |||
4801 | Info.CCEDiag(Loc, diag::note_constexpr_invalid_function, 1) | |||
4802 | << /*IsConstexpr*/0 << /*IsConstructor*/1 << CD; | |||
4803 | Info.Note(CD->getLocation(), diag::note_declared_at); | |||
4804 | } else { | |||
4805 | Info.CCEDiag(Loc, diag::note_invalid_subexpr_in_const_expr); | |||
4806 | } | |||
4807 | } | |||
4808 | return true; | |||
4809 | } | |||
4810 | ||||
4811 | /// CheckConstexprFunction - Check that a function can be called in a constant | |||
4812 | /// expression. | |||
4813 | static bool CheckConstexprFunction(EvalInfo &Info, SourceLocation CallLoc, | |||
4814 | const FunctionDecl *Declaration, | |||
4815 | const FunctionDecl *Definition, | |||
4816 | const Stmt *Body) { | |||
4817 | // Potential constant expressions can contain calls to declared, but not yet | |||
4818 | // defined, constexpr functions. | |||
4819 | if (Info.checkingPotentialConstantExpression() && !Definition && | |||
4820 | Declaration->isConstexpr()) | |||
4821 | return false; | |||
4822 | ||||
4823 | // Bail out if the function declaration itself is invalid. We will | |||
4824 | // have produced a relevant diagnostic while parsing it, so just | |||
4825 | // note the problematic sub-expression. | |||
4826 | if (Declaration->isInvalidDecl()) { | |||
4827 | Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr); | |||
4828 | return false; | |||
4829 | } | |||
4830 | ||||
4831 | // DR1872: An instantiated virtual constexpr function can't be called in a | |||
4832 | // constant expression (prior to C++20). We can still constant-fold such a | |||
4833 | // call. | |||
4834 | if (!Info.Ctx.getLangOpts().CPlusPlus2a && isa<CXXMethodDecl>(Declaration) && | |||
4835 | cast<CXXMethodDecl>(Declaration)->isVirtual()) | |||
4836 | Info.CCEDiag(CallLoc, diag::note_constexpr_virtual_call); | |||
4837 | ||||
4838 | if (Definition && Definition->isInvalidDecl()) { | |||
4839 | Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr); | |||
4840 | return false; | |||
4841 | } | |||
4842 | ||||
4843 | // Can we evaluate this function call? | |||
4844 | if (Definition && Definition->isConstexpr() && Body) | |||
4845 | return true; | |||
4846 | ||||
4847 | if (Info.getLangOpts().CPlusPlus11) { | |||
4848 | const FunctionDecl *DiagDecl = Definition ? Definition : Declaration; | |||
4849 | ||||
4850 | // If this function is not constexpr because it is an inherited | |||
4851 | // non-constexpr constructor, diagnose that directly. | |||
4852 | auto *CD = dyn_cast<CXXConstructorDecl>(DiagDecl); | |||
4853 | if (CD && CD->isInheritingConstructor()) { | |||
4854 | auto *Inherited = CD->getInheritedConstructor().getConstructor(); | |||
4855 | if (!Inherited->isConstexpr()) | |||
4856 | DiagDecl = CD = Inherited; | |||
4857 | } | |||
4858 | ||||
4859 | // FIXME: If DiagDecl is an implicitly-declared special member function | |||
4860 | // or an inheriting constructor, we should be much more explicit about why | |||
4861 | // it's not constexpr. | |||
4862 | if (CD && CD->isInheritingConstructor()) | |||
4863 | Info.FFDiag(CallLoc, diag::note_constexpr_invalid_inhctor, 1) | |||
4864 | << CD->getInheritedConstructor().getConstructor()->getParent(); | |||
4865 | else | |||
4866 | Info.FFDiag(CallLoc, diag::note_constexpr_invalid_function, 1) | |||
4867 | << DiagDecl->isConstexpr() << (bool)CD << DiagDecl; | |||
4868 | Info.Note(DiagDecl->getLocation(), diag::note_declared_at); | |||
4869 | } else { | |||
4870 | Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr); | |||
4871 | } | |||
4872 | return false; | |||
4873 | } | |||
4874 | ||||
4875 | namespace { | |||
4876 | struct CheckDynamicTypeHandler { | |||
4877 | AccessKinds AccessKind; | |||
4878 | typedef bool result_type; | |||
4879 | bool failed() { return false; } | |||
4880 | bool found(APValue &Subobj, QualType SubobjType) { return true; } | |||
4881 | bool found(APSInt &Value, QualType SubobjType) { return true; } | |||
4882 | bool found(APFloat &Value, QualType SubobjType) { return true; } | |||
4883 | }; | |||
4884 | } // end anonymous namespace | |||
4885 | ||||
4886 | /// Check that we can access the notional vptr of an object / determine its | |||
4887 | /// dynamic type. | |||
4888 | static bool checkDynamicType(EvalInfo &Info, const Expr *E, const LValue &This, | |||
4889 | AccessKinds AK, bool Polymorphic) { | |||
4890 | if (This.Designator.Invalid) | |||
4891 | return false; | |||
4892 | ||||
4893 | CompleteObject Obj = findCompleteObject(Info, E, AK, This, QualType()); | |||
4894 | ||||
4895 | if (!Obj) | |||
4896 | return false; | |||
4897 | ||||
4898 | if (!Obj.Value) { | |||
4899 | // The object is not usable in constant expressions, so we can't inspect | |||
4900 | // its value to see if it's in-lifetime or what the active union members | |||
4901 | // are. We can still check for a one-past-the-end lvalue. | |||
4902 | if (This.Designator.isOnePastTheEnd() || | |||
4903 | This.Designator.isMostDerivedAnUnsizedArray()) { | |||
4904 | Info.FFDiag(E, This.Designator.isOnePastTheEnd() | |||
4905 | ? diag::note_constexpr_access_past_end | |||
4906 | : diag::note_constexpr_access_unsized_array) | |||
4907 | << AK; | |||
4908 | return false; | |||
4909 | } else if (Polymorphic) { | |||
4910 | // Conservatively refuse to perform a polymorphic operation if we would | |||
4911 | // not be able to read a notional 'vptr' value. | |||
4912 | APValue Val; | |||
4913 | This.moveInto(Val); | |||
4914 | QualType StarThisType = | |||
4915 | Info.Ctx.getLValueReferenceType(This.Designator.getType(Info.Ctx)); | |||
4916 | Info.FFDiag(E, diag::note_constexpr_polymorphic_unknown_dynamic_type) | |||
4917 | << AK << Val.getAsString(Info.Ctx, StarThisType); | |||
4918 | return false; | |||
4919 | } | |||
4920 | return true; | |||
4921 | } | |||
4922 | ||||
4923 | CheckDynamicTypeHandler Handler{AK}; | |||
4924 | return Obj && findSubobject(Info, E, Obj, This.Designator, Handler); | |||
4925 | } | |||
4926 | ||||
4927 | /// Check that the pointee of the 'this' pointer in a member function call is | |||
4928 | /// either within its lifetime or in its period of construction or destruction. | |||
4929 | static bool | |||
4930 | checkNonVirtualMemberCallThisPointer(EvalInfo &Info, const Expr *E, | |||
4931 | const LValue &This, | |||
4932 | const CXXMethodDecl *NamedMember) { | |||
4933 | return checkDynamicType( | |||
4934 | Info, E, This, | |||
4935 | isa<CXXDestructorDecl>(NamedMember) ? AK_Destroy : AK_MemberCall, false); | |||
4936 | } | |||
4937 | ||||
4938 | struct DynamicType { | |||
4939 | /// The dynamic class type of the object. | |||
4940 | const CXXRecordDecl *Type; | |||
4941 | /// The corresponding path length in the lvalue. | |||
4942 | unsigned PathLength; | |||
4943 | }; | |||
4944 | ||||
4945 | static const CXXRecordDecl *getBaseClassType(SubobjectDesignator &Designator, | |||
4946 | unsigned PathLength) { | |||
4947 | assert(PathLength >= Designator.MostDerivedPathLength && PathLength <=((PathLength >= Designator.MostDerivedPathLength && PathLength <= Designator.Entries.size() && "invalid path length" ) ? static_cast<void> (0) : __assert_fail ("PathLength >= Designator.MostDerivedPathLength && PathLength <= Designator.Entries.size() && \"invalid path length\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 4948, __PRETTY_FUNCTION__)) | |||
4948 | Designator.Entries.size() && "invalid path length")((PathLength >= Designator.MostDerivedPathLength && PathLength <= Designator.Entries.size() && "invalid path length" ) ? static_cast<void> (0) : __assert_fail ("PathLength >= Designator.MostDerivedPathLength && PathLength <= Designator.Entries.size() && \"invalid path length\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 4948, __PRETTY_FUNCTION__)); | |||
4949 | return (PathLength == Designator.MostDerivedPathLength) | |||
4950 | ? Designator.MostDerivedType->getAsCXXRecordDecl() | |||
4951 | : getAsBaseClass(Designator.Entries[PathLength - 1]); | |||
4952 | } | |||
4953 | ||||
4954 | /// Determine the dynamic type of an object. | |||
4955 | static Optional<DynamicType> ComputeDynamicType(EvalInfo &Info, const Expr *E, | |||
4956 | LValue &This, AccessKinds AK) { | |||
4957 | // If we don't have an lvalue denoting an object of class type, there is no | |||
4958 | // meaningful dynamic type. (We consider objects of non-class type to have no | |||
4959 | // dynamic type.) | |||
4960 | if (!checkDynamicType(Info, E, This, AK, true)) | |||
4961 | return None; | |||
4962 | ||||
4963 | // Refuse to compute a dynamic type in the presence of virtual bases. This | |||
4964 | // shouldn't happen other than in constant-folding situations, since literal | |||
4965 | // types can't have virtual bases. | |||
4966 | // | |||
4967 | // Note that consumers of DynamicType assume that the type has no virtual | |||
4968 | // bases, and will need modifications if this restriction is relaxed. | |||
4969 | const CXXRecordDecl *Class = | |||
4970 | This.Designator.MostDerivedType->getAsCXXRecordDecl(); | |||
4971 | if (!Class || Class->getNumVBases()) { | |||
4972 | Info.FFDiag(E); | |||
4973 | return None; | |||
4974 | } | |||
4975 | ||||
4976 | // FIXME: For very deep class hierarchies, it might be beneficial to use a | |||
4977 | // binary search here instead. But the overwhelmingly common case is that | |||
4978 | // we're not in the middle of a constructor, so it probably doesn't matter | |||
4979 | // in practice. | |||
4980 | ArrayRef<APValue::LValuePathEntry> Path = This.Designator.Entries; | |||
4981 | for (unsigned PathLength = This.Designator.MostDerivedPathLength; | |||
4982 | PathLength <= Path.size(); ++PathLength) { | |||
4983 | switch (Info.isEvaluatingCtorDtor(This.getLValueBase(), | |||
4984 | Path.slice(0, PathLength))) { | |||
4985 | case ConstructionPhase::Bases: | |||
4986 | case ConstructionPhase::DestroyingBases: | |||
4987 | // We're constructing or destroying a base class. This is not the dynamic | |||
4988 | // type. | |||
4989 | break; | |||
4990 | ||||
4991 | case ConstructionPhase::None: | |||
4992 | case ConstructionPhase::AfterBases: | |||
4993 | case ConstructionPhase::Destroying: | |||
4994 | // We've finished constructing the base classes and not yet started | |||
4995 | // destroying them again, so this is the dynamic type. | |||
4996 | return DynamicType{getBaseClassType(This.Designator, PathLength), | |||
4997 | PathLength}; | |||
4998 | } | |||
4999 | } | |||
5000 | ||||
5001 | // CWG issue 1517: we're constructing a base class of the object described by | |||
5002 | // 'This', so that object has not yet begun its period of construction and | |||
5003 | // any polymorphic operation on it results in undefined behavior. | |||
5004 | Info.FFDiag(E); | |||
5005 | return None; | |||
5006 | } | |||
5007 | ||||
5008 | /// Perform virtual dispatch. | |||
5009 | static const CXXMethodDecl *HandleVirtualDispatch( | |||
5010 | EvalInfo &Info, const Expr *E, LValue &This, const CXXMethodDecl *Found, | |||
5011 | llvm::SmallVectorImpl<QualType> &CovariantAdjustmentPath) { | |||
5012 | Optional<DynamicType> DynType = ComputeDynamicType( | |||
5013 | Info, E, This, | |||
5014 | isa<CXXDestructorDecl>(Found) ? AK_Destroy : AK_MemberCall); | |||
5015 | if (!DynType) | |||
5016 | return nullptr; | |||
5017 | ||||
5018 | // Find the final overrider. It must be declared in one of the classes on the | |||
5019 | // path from the dynamic type to the static type. | |||
5020 | // FIXME: If we ever allow literal types to have virtual base classes, that | |||
5021 | // won't be true. | |||
5022 | const CXXMethodDecl *Callee = Found; | |||
5023 | unsigned PathLength = DynType->PathLength; | |||
5024 | for (/**/; PathLength <= This.Designator.Entries.size(); ++PathLength) { | |||
5025 | const CXXRecordDecl *Class = getBaseClassType(This.Designator, PathLength); | |||
5026 | const CXXMethodDecl *Overrider = | |||
5027 | Found->getCorrespondingMethodDeclaredInClass(Class, false); | |||
5028 | if (Overrider) { | |||
5029 | Callee = Overrider; | |||
5030 | break; | |||
5031 | } | |||
5032 | } | |||
5033 | ||||
5034 | // C++2a [class.abstract]p6: | |||
5035 | // the effect of making a virtual call to a pure virtual function [...] is | |||
5036 | // undefined | |||
5037 | if (Callee->isPure()) { | |||
5038 | Info.FFDiag(E, diag::note_constexpr_pure_virtual_call, 1) << Callee; | |||
5039 | Info.Note(Callee->getLocation(), diag::note_declared_at); | |||
5040 | return nullptr; | |||
5041 | } | |||
5042 | ||||
5043 | // If necessary, walk the rest of the path to determine the sequence of | |||
5044 | // covariant adjustment steps to apply. | |||
5045 | if (!Info.Ctx.hasSameUnqualifiedType(Callee->getReturnType(), | |||
5046 | Found->getReturnType())) { | |||
5047 | CovariantAdjustmentPath.push_back(Callee->getReturnType()); | |||
5048 | for (unsigned CovariantPathLength = PathLength + 1; | |||
5049 | CovariantPathLength != This.Designator.Entries.size(); | |||
5050 | ++CovariantPathLength) { | |||
5051 | const CXXRecordDecl *NextClass = | |||
5052 | getBaseClassType(This.Designator, CovariantPathLength); | |||
5053 | const CXXMethodDecl *Next = | |||
5054 | Found->getCorrespondingMethodDeclaredInClass(NextClass, false); | |||
5055 | if (Next && !Info.Ctx.hasSameUnqualifiedType( | |||
5056 | Next->getReturnType(), CovariantAdjustmentPath.back())) | |||
5057 | CovariantAdjustmentPath.push_back(Next->getReturnType()); | |||
5058 | } | |||
5059 | if (!Info.Ctx.hasSameUnqualifiedType(Found->getReturnType(), | |||
5060 | CovariantAdjustmentPath.back())) | |||
5061 | CovariantAdjustmentPath.push_back(Found->getReturnType()); | |||
5062 | } | |||
5063 | ||||
5064 | // Perform 'this' adjustment. | |||
5065 | if (!CastToDerivedClass(Info, E, This, Callee->getParent(), PathLength)) | |||
5066 | return nullptr; | |||
5067 | ||||
5068 | return Callee; | |||
5069 | } | |||
5070 | ||||
5071 | /// Perform the adjustment from a value returned by a virtual function to | |||
5072 | /// a value of the statically expected type, which may be a pointer or | |||
5073 | /// reference to a base class of the returned type. | |||
5074 | static bool HandleCovariantReturnAdjustment(EvalInfo &Info, const Expr *E, | |||
5075 | APValue &Result, | |||
5076 | ArrayRef<QualType> Path) { | |||
5077 | assert(Result.isLValue() &&((Result.isLValue() && "unexpected kind of APValue for covariant return" ) ? static_cast<void> (0) : __assert_fail ("Result.isLValue() && \"unexpected kind of APValue for covariant return\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5078, __PRETTY_FUNCTION__)) | |||
5078 | "unexpected kind of APValue for covariant return")((Result.isLValue() && "unexpected kind of APValue for covariant return" ) ? static_cast<void> (0) : __assert_fail ("Result.isLValue() && \"unexpected kind of APValue for covariant return\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5078, __PRETTY_FUNCTION__)); | |||
5079 | if (Result.isNullPointer()) | |||
5080 | return true; | |||
5081 | ||||
5082 | LValue LVal; | |||
5083 | LVal.setFrom(Info.Ctx, Result); | |||
5084 | ||||
5085 | const CXXRecordDecl *OldClass = Path[0]->getPointeeCXXRecordDecl(); | |||
5086 | for (unsigned I = 1; I != Path.size(); ++I) { | |||
5087 | const CXXRecordDecl *NewClass = Path[I]->getPointeeCXXRecordDecl(); | |||
5088 | assert(OldClass && NewClass && "unexpected kind of covariant return")((OldClass && NewClass && "unexpected kind of covariant return" ) ? static_cast<void> (0) : __assert_fail ("OldClass && NewClass && \"unexpected kind of covariant return\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5088, __PRETTY_FUNCTION__)); | |||
5089 | if (OldClass != NewClass && | |||
5090 | !CastToBaseClass(Info, E, LVal, OldClass, NewClass)) | |||
5091 | return false; | |||
5092 | OldClass = NewClass; | |||
5093 | } | |||
5094 | ||||
5095 | LVal.moveInto(Result); | |||
5096 | return true; | |||
5097 | } | |||
5098 | ||||
5099 | /// Determine whether \p Base, which is known to be a direct base class of | |||
5100 | /// \p Derived, is a public base class. | |||
5101 | static bool isBaseClassPublic(const CXXRecordDecl *Derived, | |||
5102 | const CXXRecordDecl *Base) { | |||
5103 | for (const CXXBaseSpecifier &BaseSpec : Derived->bases()) { | |||
5104 | auto *BaseClass = BaseSpec.getType()->getAsCXXRecordDecl(); | |||
5105 | if (BaseClass && declaresSameEntity(BaseClass, Base)) | |||
5106 | return BaseSpec.getAccessSpecifier() == AS_public; | |||
5107 | } | |||
5108 | llvm_unreachable("Base is not a direct base of Derived")::llvm::llvm_unreachable_internal("Base is not a direct base of Derived" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5108); | |||
5109 | } | |||
5110 | ||||
5111 | /// Apply the given dynamic cast operation on the provided lvalue. | |||
5112 | /// | |||
5113 | /// This implements the hard case of dynamic_cast, requiring a "runtime check" | |||
5114 | /// to find a suitable target subobject. | |||
5115 | static bool HandleDynamicCast(EvalInfo &Info, const ExplicitCastExpr *E, | |||
5116 | LValue &Ptr) { | |||
5117 | // We can't do anything with a non-symbolic pointer value. | |||
5118 | SubobjectDesignator &D = Ptr.Designator; | |||
5119 | if (D.Invalid) | |||
5120 | return false; | |||
5121 | ||||
5122 | // C++ [expr.dynamic.cast]p6: | |||
5123 | // If v is a null pointer value, the result is a null pointer value. | |||
5124 | if (Ptr.isNullPointer() && !E->isGLValue()) | |||
5125 | return true; | |||
5126 | ||||
5127 | // For all the other cases, we need the pointer to point to an object within | |||
5128 | // its lifetime / period of construction / destruction, and we need to know | |||
5129 | // its dynamic type. | |||
5130 | Optional<DynamicType> DynType = | |||
5131 | ComputeDynamicType(Info, E, Ptr, AK_DynamicCast); | |||
5132 | if (!DynType) | |||
5133 | return false; | |||
5134 | ||||
5135 | // C++ [expr.dynamic.cast]p7: | |||
5136 | // If T is "pointer to cv void", then the result is a pointer to the most | |||
5137 | // derived object | |||
5138 | if (E->getType()->isVoidPointerType()) | |||
5139 | return CastToDerivedClass(Info, E, Ptr, DynType->Type, DynType->PathLength); | |||
5140 | ||||
5141 | const CXXRecordDecl *C = E->getTypeAsWritten()->getPointeeCXXRecordDecl(); | |||
5142 | assert(C && "dynamic_cast target is not void pointer nor class")((C && "dynamic_cast target is not void pointer nor class" ) ? static_cast<void> (0) : __assert_fail ("C && \"dynamic_cast target is not void pointer nor class\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5142, __PRETTY_FUNCTION__)); | |||
5143 | CanQualType CQT = Info.Ctx.getCanonicalType(Info.Ctx.getRecordType(C)); | |||
5144 | ||||
5145 | auto RuntimeCheckFailed = [&] (CXXBasePaths *Paths) { | |||
5146 | // C++ [expr.dynamic.cast]p9: | |||
5147 | if (!E->isGLValue()) { | |||
5148 | // The value of a failed cast to pointer type is the null pointer value | |||
5149 | // of the required result type. | |||
5150 | auto TargetVal = Info.Ctx.getTargetNullPointerValue(E->getType()); | |||
5151 | Ptr.setNull(E->getType(), TargetVal); | |||
5152 | return true; | |||
5153 | } | |||
5154 | ||||
5155 | // A failed cast to reference type throws [...] std::bad_cast. | |||
5156 | unsigned DiagKind; | |||
5157 | if (!Paths && (declaresSameEntity(DynType->Type, C) || | |||
5158 | DynType->Type->isDerivedFrom(C))) | |||
5159 | DiagKind = 0; | |||
5160 | else if (!Paths || Paths->begin() == Paths->end()) | |||
5161 | DiagKind = 1; | |||
5162 | else if (Paths->isAmbiguous(CQT)) | |||
5163 | DiagKind = 2; | |||
5164 | else { | |||
5165 | assert(Paths->front().Access != AS_public && "why did the cast fail?")((Paths->front().Access != AS_public && "why did the cast fail?" ) ? static_cast<void> (0) : __assert_fail ("Paths->front().Access != AS_public && \"why did the cast fail?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5165, __PRETTY_FUNCTION__)); | |||
5166 | DiagKind = 3; | |||
5167 | } | |||
5168 | Info.FFDiag(E, diag::note_constexpr_dynamic_cast_to_reference_failed) | |||
5169 | << DiagKind << Ptr.Designator.getType(Info.Ctx) | |||
5170 | << Info.Ctx.getRecordType(DynType->Type) | |||
5171 | << E->getType().getUnqualifiedType(); | |||
5172 | return false; | |||
5173 | }; | |||
5174 | ||||
5175 | // Runtime check, phase 1: | |||
5176 | // Walk from the base subobject towards the derived object looking for the | |||
5177 | // target type. | |||
5178 | for (int PathLength = Ptr.Designator.Entries.size(); | |||
5179 | PathLength >= (int)DynType->PathLength; --PathLength) { | |||
5180 | const CXXRecordDecl *Class = getBaseClassType(Ptr.Designator, PathLength); | |||
5181 | if (declaresSameEntity(Class, C)) | |||
5182 | return CastToDerivedClass(Info, E, Ptr, Class, PathLength); | |||
5183 | // We can only walk across public inheritance edges. | |||
5184 | if (PathLength > (int)DynType->PathLength && | |||
5185 | !isBaseClassPublic(getBaseClassType(Ptr.Designator, PathLength - 1), | |||
5186 | Class)) | |||
5187 | return RuntimeCheckFailed(nullptr); | |||
5188 | } | |||
5189 | ||||
5190 | // Runtime check, phase 2: | |||
5191 | // Search the dynamic type for an unambiguous public base of type C. | |||
5192 | CXXBasePaths Paths(/*FindAmbiguities=*/true, | |||
5193 | /*RecordPaths=*/true, /*DetectVirtual=*/false); | |||
5194 | if (DynType->Type->isDerivedFrom(C, Paths) && !Paths.isAmbiguous(CQT) && | |||
5195 | Paths.front().Access == AS_public) { | |||
5196 | // Downcast to the dynamic type... | |||
5197 | if (!CastToDerivedClass(Info, E, Ptr, DynType->Type, DynType->PathLength)) | |||
5198 | return false; | |||
5199 | // ... then upcast to the chosen base class subobject. | |||
5200 | for (CXXBasePathElement &Elem : Paths.front()) | |||
5201 | if (!HandleLValueBase(Info, E, Ptr, Elem.Class, Elem.Base)) | |||
5202 | return false; | |||
5203 | return true; | |||
5204 | } | |||
5205 | ||||
5206 | // Otherwise, the runtime check fails. | |||
5207 | return RuntimeCheckFailed(&Paths); | |||
5208 | } | |||
5209 | ||||
5210 | namespace { | |||
5211 | struct StartLifetimeOfUnionMemberHandler { | |||
5212 | const FieldDecl *Field; | |||
5213 | ||||
5214 | static const AccessKinds AccessKind = AK_Assign; | |||
5215 | ||||
5216 | typedef bool result_type; | |||
5217 | bool failed() { return false; } | |||
5218 | bool found(APValue &Subobj, QualType SubobjType) { | |||
5219 | // We are supposed to perform no initialization but begin the lifetime of | |||
5220 | // the object. We interpret that as meaning to do what default | |||
5221 | // initialization of the object would do if all constructors involved were | |||
5222 | // trivial: | |||
5223 | // * All base, non-variant member, and array element subobjects' lifetimes | |||
5224 | // begin | |||
5225 | // * No variant members' lifetimes begin | |||
5226 | // * All scalar subobjects whose lifetimes begin have indeterminate values | |||
5227 | assert(SubobjType->isUnionType())((SubobjType->isUnionType()) ? static_cast<void> (0) : __assert_fail ("SubobjType->isUnionType()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5227, __PRETTY_FUNCTION__)); | |||
5228 | if (!declaresSameEntity(Subobj.getUnionField(), Field) || | |||
5229 | !Subobj.getUnionValue().hasValue()) | |||
5230 | Subobj.setUnion(Field, getDefaultInitValue(Field->getType())); | |||
5231 | return true; | |||
5232 | } | |||
5233 | bool found(APSInt &Value, QualType SubobjType) { | |||
5234 | llvm_unreachable("wrong value kind for union object")::llvm::llvm_unreachable_internal("wrong value kind for union object" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5234); | |||
5235 | } | |||
5236 | bool found(APFloat &Value, QualType SubobjType) { | |||
5237 | llvm_unreachable("wrong value kind for union object")::llvm::llvm_unreachable_internal("wrong value kind for union object" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5237); | |||
5238 | } | |||
5239 | }; | |||
5240 | } // end anonymous namespace | |||
5241 | ||||
5242 | const AccessKinds StartLifetimeOfUnionMemberHandler::AccessKind; | |||
5243 | ||||
5244 | /// Handle a builtin simple-assignment or a call to a trivial assignment | |||
5245 | /// operator whose left-hand side might involve a union member access. If it | |||
5246 | /// does, implicitly start the lifetime of any accessed union elements per | |||
5247 | /// C++20 [class.union]5. | |||
5248 | static bool HandleUnionActiveMemberChange(EvalInfo &Info, const Expr *LHSExpr, | |||
5249 | const LValue &LHS) { | |||
5250 | if (LHS.InvalidBase || LHS.Designator.Invalid) | |||
5251 | return false; | |||
5252 | ||||
5253 | llvm::SmallVector<std::pair<unsigned, const FieldDecl*>, 4> UnionPathLengths; | |||
5254 | // C++ [class.union]p5: | |||
5255 | // define the set S(E) of subexpressions of E as follows: | |||
5256 | unsigned PathLength = LHS.Designator.Entries.size(); | |||
5257 | for (const Expr *E = LHSExpr; E != nullptr;) { | |||
5258 | // -- If E is of the form A.B, S(E) contains the elements of S(A)... | |||
5259 | if (auto *ME = dyn_cast<MemberExpr>(E)) { | |||
5260 | auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()); | |||
5261 | // Note that we can't implicitly start the lifetime of a reference, | |||
5262 | // so we don't need to proceed any further if we reach one. | |||
5263 | if (!FD || FD->getType()->isReferenceType()) | |||
5264 | break; | |||
5265 | ||||
5266 | // ... and also contains A.B if B names a union member | |||
5267 | if (FD->getParent()->isUnion()) | |||
5268 | UnionPathLengths.push_back({PathLength - 1, FD}); | |||
5269 | ||||
5270 | E = ME->getBase(); | |||
5271 | --PathLength; | |||
5272 | assert(declaresSameEntity(FD,((declaresSameEntity(FD, LHS.Designator.Entries[PathLength] . getAsBaseOrMember().getPointer())) ? static_cast<void> ( 0) : __assert_fail ("declaresSameEntity(FD, LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5274, __PRETTY_FUNCTION__)) | |||
5273 | LHS.Designator.Entries[PathLength]((declaresSameEntity(FD, LHS.Designator.Entries[PathLength] . getAsBaseOrMember().getPointer())) ? static_cast<void> ( 0) : __assert_fail ("declaresSameEntity(FD, LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5274, __PRETTY_FUNCTION__)) | |||
5274 | .getAsBaseOrMember().getPointer()))((declaresSameEntity(FD, LHS.Designator.Entries[PathLength] . getAsBaseOrMember().getPointer())) ? static_cast<void> ( 0) : __assert_fail ("declaresSameEntity(FD, LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5274, __PRETTY_FUNCTION__)); | |||
5275 | ||||
5276 | // -- If E is of the form A[B] and is interpreted as a built-in array | |||
5277 | // subscripting operator, S(E) is [S(the array operand, if any)]. | |||
5278 | } else if (auto *ASE = dyn_cast<ArraySubscriptExpr>(E)) { | |||
5279 | // Step over an ArrayToPointerDecay implicit cast. | |||
5280 | auto *Base = ASE->getBase()->IgnoreImplicit(); | |||
5281 | if (!Base->getType()->isArrayType()) | |||
5282 | break; | |||
5283 | ||||
5284 | E = Base; | |||
5285 | --PathLength; | |||
5286 | ||||
5287 | } else if (auto *ICE = dyn_cast<ImplicitCastExpr>(E)) { | |||
5288 | // Step over a derived-to-base conversion. | |||
5289 | E = ICE->getSubExpr(); | |||
5290 | if (ICE->getCastKind() == CK_NoOp) | |||
5291 | continue; | |||
5292 | if (ICE->getCastKind() != CK_DerivedToBase && | |||
5293 | ICE->getCastKind() != CK_UncheckedDerivedToBase) | |||
5294 | break; | |||
5295 | // Walk path backwards as we walk up from the base to the derived class. | |||
5296 | for (const CXXBaseSpecifier *Elt : llvm::reverse(ICE->path())) { | |||
5297 | --PathLength; | |||
5298 | (void)Elt; | |||
5299 | assert(declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(),((declaresSameEntity(Elt->getType()->getAsCXXRecordDecl (), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer ())) ? static_cast<void> (0) : __assert_fail ("declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5301, __PRETTY_FUNCTION__)) | |||
5300 | LHS.Designator.Entries[PathLength]((declaresSameEntity(Elt->getType()->getAsCXXRecordDecl (), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer ())) ? static_cast<void> (0) : __assert_fail ("declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5301, __PRETTY_FUNCTION__)) | |||
5301 | .getAsBaseOrMember().getPointer()))((declaresSameEntity(Elt->getType()->getAsCXXRecordDecl (), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer ())) ? static_cast<void> (0) : __assert_fail ("declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5301, __PRETTY_FUNCTION__)); | |||
5302 | } | |||
5303 | ||||
5304 | // -- Otherwise, S(E) is empty. | |||
5305 | } else { | |||
5306 | break; | |||
5307 | } | |||
5308 | } | |||
5309 | ||||
5310 | // Common case: no unions' lifetimes are started. | |||
5311 | if (UnionPathLengths.empty()) | |||
5312 | return true; | |||
5313 | ||||
5314 | // if modification of X [would access an inactive union member], an object | |||
5315 | // of the type of X is implicitly created | |||
5316 | CompleteObject Obj = | |||
5317 | findCompleteObject(Info, LHSExpr, AK_Assign, LHS, LHSExpr->getType()); | |||
5318 | if (!Obj) | |||
5319 | return false; | |||
5320 | for (std::pair<unsigned, const FieldDecl *> LengthAndField : | |||
5321 | llvm::reverse(UnionPathLengths)) { | |||
5322 | // Form a designator for the union object. | |||
5323 | SubobjectDesignator D = LHS.Designator; | |||
5324 | D.truncate(Info.Ctx, LHS.Base, LengthAndField.first); | |||
5325 | ||||
5326 | StartLifetimeOfUnionMemberHandler StartLifetime{LengthAndField.second}; | |||
5327 | if (!findSubobject(Info, LHSExpr, Obj, D, StartLifetime)) | |||
5328 | return false; | |||
5329 | } | |||
5330 | ||||
5331 | return true; | |||
5332 | } | |||
5333 | ||||
5334 | /// Determine if a class has any fields that might need to be copied by a | |||
5335 | /// trivial copy or move operation. | |||
5336 | static bool hasFields(const CXXRecordDecl *RD) { | |||
5337 | if (!RD || RD->isEmpty()) | |||
5338 | return false; | |||
5339 | for (auto *FD : RD->fields()) { | |||
5340 | if (FD->isUnnamedBitfield()) | |||
5341 | continue; | |||
5342 | return true; | |||
5343 | } | |||
5344 | for (auto &Base : RD->bases()) | |||
5345 | if (hasFields(Base.getType()->getAsCXXRecordDecl())) | |||
5346 | return true; | |||
5347 | return false; | |||
5348 | } | |||
5349 | ||||
5350 | namespace { | |||
5351 | typedef SmallVector<APValue, 8> ArgVector; | |||
5352 | } | |||
5353 | ||||
5354 | /// EvaluateArgs - Evaluate the arguments to a function call. | |||
5355 | static bool EvaluateArgs(ArrayRef<const Expr *> Args, ArgVector &ArgValues, | |||
5356 | EvalInfo &Info, const FunctionDecl *Callee) { | |||
5357 | bool Success = true; | |||
5358 | llvm::SmallBitVector ForbiddenNullArgs; | |||
5359 | if (Callee->hasAttr<NonNullAttr>()) { | |||
5360 | ForbiddenNullArgs.resize(Args.size()); | |||
5361 | for (const auto *Attr : Callee->specific_attrs<NonNullAttr>()) { | |||
5362 | if (!Attr->args_size()) { | |||
5363 | ForbiddenNullArgs.set(); | |||
5364 | break; | |||
5365 | } else | |||
5366 | for (auto Idx : Attr->args()) { | |||
5367 | unsigned ASTIdx = Idx.getASTIndex(); | |||
5368 | if (ASTIdx >= Args.size()) | |||
5369 | continue; | |||
5370 | ForbiddenNullArgs[ASTIdx] = 1; | |||
5371 | } | |||
5372 | } | |||
5373 | } | |||
5374 | for (ArrayRef<const Expr*>::iterator I = Args.begin(), E = Args.end(); | |||
5375 | I != E; ++I) { | |||
5376 | if (!Evaluate(ArgValues[I - Args.begin()], Info, *I)) { | |||
5377 | // If we're checking for a potential constant expression, evaluate all | |||
5378 | // initializers even if some of them fail. | |||
5379 | if (!Info.noteFailure()) | |||
5380 | return false; | |||
5381 | Success = false; | |||
5382 | } else if (!ForbiddenNullArgs.empty() && | |||
5383 | ForbiddenNullArgs[I - Args.begin()] && | |||
5384 | ArgValues[I - Args.begin()].isNullPointer()) { | |||
5385 | Info.CCEDiag(*I, diag::note_non_null_attribute_failed); | |||
5386 | if (!Info.noteFailure()) | |||
5387 | return false; | |||
5388 | Success = false; | |||
5389 | } | |||
5390 | } | |||
5391 | return Success; | |||
5392 | } | |||
5393 | ||||
5394 | /// Evaluate a function call. | |||
5395 | static bool HandleFunctionCall(SourceLocation CallLoc, | |||
5396 | const FunctionDecl *Callee, const LValue *This, | |||
5397 | ArrayRef<const Expr*> Args, const Stmt *Body, | |||
5398 | EvalInfo &Info, APValue &Result, | |||
5399 | const LValue *ResultSlot) { | |||
5400 | ArgVector ArgValues(Args.size()); | |||
5401 | if (!EvaluateArgs(Args, ArgValues, Info, Callee)) | |||
5402 | return false; | |||
5403 | ||||
5404 | if (!Info.CheckCallLimit(CallLoc)) | |||
5405 | return false; | |||
5406 | ||||
5407 | CallStackFrame Frame(Info, CallLoc, Callee, This, ArgValues.data()); | |||
5408 | ||||
5409 | // For a trivial copy or move assignment, perform an APValue copy. This is | |||
5410 | // essential for unions, where the operations performed by the assignment | |||
5411 | // operator cannot be represented as statements. | |||
5412 | // | |||
5413 | // Skip this for non-union classes with no fields; in that case, the defaulted | |||
5414 | // copy/move does not actually read the object. | |||
5415 | const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Callee); | |||
5416 | if (MD && MD->isDefaulted() && | |||
5417 | (MD->getParent()->isUnion() || | |||
5418 | (MD->isTrivial() && hasFields(MD->getParent())))) { | |||
5419 | assert(This &&((This && (MD->isCopyAssignmentOperator() || MD-> isMoveAssignmentOperator())) ? static_cast<void> (0) : __assert_fail ("This && (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5420, __PRETTY_FUNCTION__)) | |||
5420 | (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator()))((This && (MD->isCopyAssignmentOperator() || MD-> isMoveAssignmentOperator())) ? static_cast<void> (0) : __assert_fail ("This && (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5420, __PRETTY_FUNCTION__)); | |||
5421 | LValue RHS; | |||
5422 | RHS.setFrom(Info.Ctx, ArgValues[0]); | |||
5423 | APValue RHSValue; | |||
5424 | if (!handleLValueToRValueConversion(Info, Args[0], Args[0]->getType(), RHS, | |||
5425 | RHSValue, MD->getParent()->isUnion())) | |||
5426 | return false; | |||
5427 | if (Info.getLangOpts().CPlusPlus2a && MD->isTrivial() && | |||
5428 | !HandleUnionActiveMemberChange(Info, Args[0], *This)) | |||
5429 | return false; | |||
5430 | if (!handleAssignment(Info, Args[0], *This, MD->getThisType(), | |||
5431 | RHSValue)) | |||
5432 | return false; | |||
5433 | This->moveInto(Result); | |||
5434 | return true; | |||
5435 | } else if (MD && isLambdaCallOperator(MD)) { | |||
5436 | // We're in a lambda; determine the lambda capture field maps unless we're | |||
5437 | // just constexpr checking a lambda's call operator. constexpr checking is | |||
5438 | // done before the captures have been added to the closure object (unless | |||
5439 | // we're inferring constexpr-ness), so we don't have access to them in this | |||
5440 | // case. But since we don't need the captures to constexpr check, we can | |||
5441 | // just ignore them. | |||
5442 | if (!Info.checkingPotentialConstantExpression()) | |||
5443 | MD->getParent()->getCaptureFields(Frame.LambdaCaptureFields, | |||
5444 | Frame.LambdaThisCaptureField); | |||
5445 | } | |||
5446 | ||||
5447 | StmtResult Ret = {Result, ResultSlot}; | |||
5448 | EvalStmtResult ESR = EvaluateStmt(Ret, Info, Body); | |||
5449 | if (ESR == ESR_Succeeded) { | |||
5450 | if (Callee->getReturnType()->isVoidType()) | |||
5451 | return true; | |||
5452 | Info.FFDiag(Callee->getEndLoc(), diag::note_constexpr_no_return); | |||
5453 | } | |||
5454 | return ESR == ESR_Returned; | |||
5455 | } | |||
5456 | ||||
5457 | /// Evaluate a constructor call. | |||
5458 | static bool HandleConstructorCall(const Expr *E, const LValue &This, | |||
5459 | APValue *ArgValues, | |||
5460 | const CXXConstructorDecl *Definition, | |||
5461 | EvalInfo &Info, APValue &Result) { | |||
5462 | SourceLocation CallLoc = E->getExprLoc(); | |||
5463 | if (!Info.CheckCallLimit(CallLoc)) | |||
5464 | return false; | |||
5465 | ||||
5466 | const CXXRecordDecl *RD = Definition->getParent(); | |||
5467 | if (RD->getNumVBases()) { | |||
5468 | Info.FFDiag(CallLoc, diag::note_constexpr_virtual_base) << RD; | |||
5469 | return false; | |||
5470 | } | |||
5471 | ||||
5472 | EvalInfo::EvaluatingConstructorRAII EvalObj( | |||
5473 | Info, | |||
5474 | ObjectUnderConstruction{This.getLValueBase(), This.Designator.Entries}, | |||
5475 | RD->getNumBases()); | |||
5476 | CallStackFrame Frame(Info, CallLoc, Definition, &This, ArgValues); | |||
5477 | ||||
5478 | // FIXME: Creating an APValue just to hold a nonexistent return value is | |||
5479 | // wasteful. | |||
5480 | APValue RetVal; | |||
5481 | StmtResult Ret = {RetVal, nullptr}; | |||
5482 | ||||
5483 | // If it's a delegating constructor, delegate. | |||
5484 | if (Definition->isDelegatingConstructor()) { | |||
5485 | CXXConstructorDecl::init_const_iterator I = Definition->init_begin(); | |||
5486 | { | |||
5487 | FullExpressionRAII InitScope(Info); | |||
5488 | if (!EvaluateInPlace(Result, Info, This, (*I)->getInit()) || | |||
5489 | !InitScope.destroy()) | |||
5490 | return false; | |||
5491 | } | |||
5492 | return EvaluateStmt(Ret, Info, Definition->getBody()) != ESR_Failed; | |||
5493 | } | |||
5494 | ||||
5495 | // For a trivial copy or move constructor, perform an APValue copy. This is | |||
5496 | // essential for unions (or classes with anonymous union members), where the | |||
5497 | // operations performed by the constructor cannot be represented by | |||
5498 | // ctor-initializers. | |||
5499 | // | |||
5500 | // Skip this for empty non-union classes; we should not perform an | |||
5501 | // lvalue-to-rvalue conversion on them because their copy constructor does not | |||
5502 | // actually read them. | |||
5503 | if (Definition->isDefaulted() && Definition->isCopyOrMoveConstructor() && | |||
5504 | (Definition->getParent()->isUnion() || | |||
5505 | (Definition->isTrivial() && hasFields(Definition->getParent())))) { | |||
5506 | LValue RHS; | |||
5507 | RHS.setFrom(Info.Ctx, ArgValues[0]); | |||
5508 | return handleLValueToRValueConversion( | |||
5509 | Info, E, Definition->getParamDecl(0)->getType().getNonReferenceType(), | |||
5510 | RHS, Result, Definition->getParent()->isUnion()); | |||
5511 | } | |||
5512 | ||||
5513 | // Reserve space for the struct members. | |||
5514 | if (!RD->isUnion() && !Result.hasValue()) | |||
5515 | Result = APValue(APValue::UninitStruct(), RD->getNumBases(), | |||
5516 | std::distance(RD->field_begin(), RD->field_end())); | |||
5517 | ||||
5518 | if (RD->isInvalidDecl()) return false; | |||
5519 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
5520 | ||||
5521 | // A scope for temporaries lifetime-extended by reference members. | |||
5522 | BlockScopeRAII LifetimeExtendedScope(Info); | |||
5523 | ||||
5524 | bool Success = true; | |||
5525 | unsigned BasesSeen = 0; | |||
5526 | #ifndef NDEBUG | |||
5527 | CXXRecordDecl::base_class_const_iterator BaseIt = RD->bases_begin(); | |||
5528 | #endif | |||
5529 | CXXRecordDecl::field_iterator FieldIt = RD->field_begin(); | |||
5530 | auto SkipToField = [&](FieldDecl *FD, bool Indirect) { | |||
5531 | // We might be initializing the same field again if this is an indirect | |||
5532 | // field initialization. | |||
5533 | if (FieldIt == RD->field_end() || | |||
5534 | FieldIt->getFieldIndex() > FD->getFieldIndex()) { | |||
5535 | assert(Indirect && "fields out of order?")((Indirect && "fields out of order?") ? static_cast< void> (0) : __assert_fail ("Indirect && \"fields out of order?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5535, __PRETTY_FUNCTION__)); | |||
5536 | return; | |||
5537 | } | |||
5538 | ||||
5539 | // Default-initialize any fields with no explicit initializer. | |||
5540 | for (; !declaresSameEntity(*FieldIt, FD); ++FieldIt) { | |||
5541 | assert(FieldIt != RD->field_end() && "missing field?")((FieldIt != RD->field_end() && "missing field?") ? static_cast<void> (0) : __assert_fail ("FieldIt != RD->field_end() && \"missing field?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5541, __PRETTY_FUNCTION__)); | |||
5542 | if (!FieldIt->isUnnamedBitfield()) | |||
5543 | Result.getStructField(FieldIt->getFieldIndex()) = | |||
5544 | getDefaultInitValue(FieldIt->getType()); | |||
5545 | } | |||
5546 | ++FieldIt; | |||
5547 | }; | |||
5548 | for (const auto *I : Definition->inits()) { | |||
5549 | LValue Subobject = This; | |||
5550 | LValue SubobjectParent = This; | |||
5551 | APValue *Value = &Result; | |||
5552 | ||||
5553 | // Determine the subobject to initialize. | |||
5554 | FieldDecl *FD = nullptr; | |||
5555 | if (I->isBaseInitializer()) { | |||
5556 | QualType BaseType(I->getBaseClass(), 0); | |||
5557 | #ifndef NDEBUG | |||
5558 | // Non-virtual base classes are initialized in the order in the class | |||
5559 | // definition. We have already checked for virtual base classes. | |||
5560 | assert(!BaseIt->isVirtual() && "virtual base for literal type")((!BaseIt->isVirtual() && "virtual base for literal type" ) ? static_cast<void> (0) : __assert_fail ("!BaseIt->isVirtual() && \"virtual base for literal type\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5560, __PRETTY_FUNCTION__)); | |||
5561 | assert(Info.Ctx.hasSameType(BaseIt->getType(), BaseType) &&((Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && "base class initializers not in expected order") ? static_cast <void> (0) : __assert_fail ("Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && \"base class initializers not in expected order\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5562, __PRETTY_FUNCTION__)) | |||
5562 | "base class initializers not in expected order")((Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && "base class initializers not in expected order") ? static_cast <void> (0) : __assert_fail ("Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && \"base class initializers not in expected order\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5562, __PRETTY_FUNCTION__)); | |||
5563 | ++BaseIt; | |||
5564 | #endif | |||
5565 | if (!HandleLValueDirectBase(Info, I->getInit(), Subobject, RD, | |||
5566 | BaseType->getAsCXXRecordDecl(), &Layout)) | |||
5567 | return false; | |||
5568 | Value = &Result.getStructBase(BasesSeen++); | |||
5569 | } else if ((FD = I->getMember())) { | |||
5570 | if (!HandleLValueMember(Info, I->getInit(), Subobject, FD, &Layout)) | |||
5571 | return false; | |||
5572 | if (RD->isUnion()) { | |||
5573 | Result = APValue(FD); | |||
5574 | Value = &Result.getUnionValue(); | |||
5575 | } else { | |||
5576 | SkipToField(FD, false); | |||
5577 | Value = &Result.getStructField(FD->getFieldIndex()); | |||
5578 | } | |||
5579 | } else if (IndirectFieldDecl *IFD = I->getIndirectMember()) { | |||
5580 | // Walk the indirect field decl's chain to find the object to initialize, | |||
5581 | // and make sure we've initialized every step along it. | |||
5582 | auto IndirectFieldChain = IFD->chain(); | |||
5583 | for (auto *C : IndirectFieldChain) { | |||
5584 | FD = cast<FieldDecl>(C); | |||
5585 | CXXRecordDecl *CD = cast<CXXRecordDecl>(FD->getParent()); | |||
5586 | // Switch the union field if it differs. This happens if we had | |||
5587 | // preceding zero-initialization, and we're now initializing a union | |||
5588 | // subobject other than the first. | |||
5589 | // FIXME: In this case, the values of the other subobjects are | |||
5590 | // specified, since zero-initialization sets all padding bits to zero. | |||
5591 | if (!Value->hasValue() || | |||
5592 | (Value->isUnion() && Value->getUnionField() != FD)) { | |||
5593 | if (CD->isUnion()) | |||
5594 | *Value = APValue(FD); | |||
5595 | else | |||
5596 | // FIXME: This immediately starts the lifetime of all members of an | |||
5597 | // anonymous struct. It would be preferable to strictly start member | |||
5598 | // lifetime in initialization order. | |||
5599 | *Value = getDefaultInitValue(Info.Ctx.getRecordType(CD)); | |||
5600 | } | |||
5601 | // Store Subobject as its parent before updating it for the last element | |||
5602 | // in the chain. | |||
5603 | if (C == IndirectFieldChain.back()) | |||
5604 | SubobjectParent = Subobject; | |||
5605 | if (!HandleLValueMember(Info, I->getInit(), Subobject, FD)) | |||
5606 | return false; | |||
5607 | if (CD->isUnion()) | |||
5608 | Value = &Value->getUnionValue(); | |||
5609 | else { | |||
5610 | if (C == IndirectFieldChain.front() && !RD->isUnion()) | |||
5611 | SkipToField(FD, true); | |||
5612 | Value = &Value->getStructField(FD->getFieldIndex()); | |||
5613 | } | |||
5614 | } | |||
5615 | } else { | |||
5616 | llvm_unreachable("unknown base initializer kind")::llvm::llvm_unreachable_internal("unknown base initializer kind" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5616); | |||
5617 | } | |||
5618 | ||||
5619 | // Need to override This for implicit field initializers as in this case | |||
5620 | // This refers to innermost anonymous struct/union containing initializer, | |||
5621 | // not to currently constructed class. | |||
5622 | const Expr *Init = I->getInit(); | |||
5623 | ThisOverrideRAII ThisOverride(*Info.CurrentCall, &SubobjectParent, | |||
5624 | isa<CXXDefaultInitExpr>(Init)); | |||
5625 | FullExpressionRAII InitScope(Info); | |||
5626 | if (!EvaluateInPlace(*Value, Info, Subobject, Init) || | |||
5627 | (FD && FD->isBitField() && | |||
5628 | !truncateBitfieldValue(Info, Init, *Value, FD))) { | |||
5629 | // If we're checking for a potential constant expression, evaluate all | |||
5630 | // initializers even if some of them fail. | |||
5631 | if (!Info.noteFailure()) | |||
5632 | return false; | |||
5633 | Success = false; | |||
5634 | } | |||
5635 | ||||
5636 | // This is the point at which the dynamic type of the object becomes this | |||
5637 | // class type. | |||
5638 | if (I->isBaseInitializer() && BasesSeen == RD->getNumBases()) | |||
5639 | EvalObj.finishedConstructingBases(); | |||
5640 | } | |||
5641 | ||||
5642 | // Default-initialize any remaining fields. | |||
5643 | if (!RD->isUnion()) { | |||
5644 | for (; FieldIt != RD->field_end(); ++FieldIt) { | |||
5645 | if (!FieldIt->isUnnamedBitfield()) | |||
5646 | Result.getStructField(FieldIt->getFieldIndex()) = | |||
5647 | getDefaultInitValue(FieldIt->getType()); | |||
5648 | } | |||
5649 | } | |||
5650 | ||||
5651 | return Success && | |||
5652 | EvaluateStmt(Ret, Info, Definition->getBody()) != ESR_Failed && | |||
5653 | LifetimeExtendedScope.destroy(); | |||
5654 | } | |||
5655 | ||||
5656 | static bool HandleConstructorCall(const Expr *E, const LValue &This, | |||
5657 | ArrayRef<const Expr*> Args, | |||
5658 | const CXXConstructorDecl *Definition, | |||
5659 | EvalInfo &Info, APValue &Result) { | |||
5660 | ArgVector ArgValues(Args.size()); | |||
5661 | if (!EvaluateArgs(Args, ArgValues, Info, Definition)) | |||
5662 | return false; | |||
5663 | ||||
5664 | return HandleConstructorCall(E, This, ArgValues.data(), Definition, | |||
5665 | Info, Result); | |||
5666 | } | |||
5667 | ||||
5668 | static bool HandleDestructionImpl(EvalInfo &Info, SourceLocation CallLoc, | |||
5669 | const LValue &This, APValue &Value, | |||
5670 | QualType T) { | |||
5671 | // Objects can only be destroyed while they're within their lifetimes. | |||
5672 | // FIXME: We have no representation for whether an object of type nullptr_t | |||
5673 | // is in its lifetime; it usually doesn't matter. Perhaps we should model it | |||
5674 | // as indeterminate instead? | |||
5675 | if (Value.isAbsent() && !T->isNullPtrType()) { | |||
5676 | APValue Printable; | |||
5677 | This.moveInto(Printable); | |||
5678 | Info.FFDiag(CallLoc, diag::note_constexpr_destroy_out_of_lifetime) | |||
5679 | << Printable.getAsString(Info.Ctx, Info.Ctx.getLValueReferenceType(T)); | |||
5680 | return false; | |||
5681 | } | |||
5682 | ||||
5683 | // Invent an expression for location purposes. | |||
5684 | // FIXME: We shouldn't need to do this. | |||
5685 | OpaqueValueExpr LocE(CallLoc, Info.Ctx.IntTy, VK_RValue); | |||
5686 | ||||
5687 | // For arrays, destroy elements right-to-left. | |||
5688 | if (const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(T)) { | |||
5689 | uint64_t Size = CAT->getSize().getZExtValue(); | |||
5690 | QualType ElemT = CAT->getElementType(); | |||
5691 | ||||
5692 | LValue ElemLV = This; | |||
5693 | ElemLV.addArray(Info, &LocE, CAT); | |||
5694 | if (!HandleLValueArrayAdjustment(Info, &LocE, ElemLV, ElemT, Size)) | |||
5695 | return false; | |||
5696 | ||||
5697 | // Ensure that we have actual array elements available to destroy; the | |||
5698 | // destructors might mutate the value, so we can't run them on the array | |||
5699 | // filler. | |||
5700 | if (Size && Size > Value.getArrayInitializedElts()) | |||
5701 | expandArray(Value, Value.getArraySize() - 1); | |||
5702 | ||||
5703 | for (; Size != 0; --Size) { | |||
5704 | APValue &Elem = Value.getArrayInitializedElt(Size - 1); | |||
5705 | if (!HandleLValueArrayAdjustment(Info, &LocE, ElemLV, ElemT, -1) || | |||
5706 | !HandleDestructionImpl(Info, CallLoc, ElemLV, Elem, ElemT)) | |||
5707 | return false; | |||
5708 | } | |||
5709 | ||||
5710 | // End the lifetime of this array now. | |||
5711 | Value = APValue(); | |||
5712 | return true; | |||
5713 | } | |||
5714 | ||||
5715 | const CXXRecordDecl *RD = T->getAsCXXRecordDecl(); | |||
5716 | if (!RD) { | |||
5717 | if (T.isDestructedType()) { | |||
5718 | Info.FFDiag(CallLoc, diag::note_constexpr_unsupported_destruction) << T; | |||
5719 | return false; | |||
5720 | } | |||
5721 | ||||
5722 | Value = APValue(); | |||
5723 | return true; | |||
5724 | } | |||
5725 | ||||
5726 | if (RD->getNumVBases()) { | |||
5727 | Info.FFDiag(CallLoc, diag::note_constexpr_virtual_base) << RD; | |||
5728 | return false; | |||
5729 | } | |||
5730 | ||||
5731 | const CXXDestructorDecl *DD = RD->getDestructor(); | |||
5732 | if (!DD && !RD->hasTrivialDestructor()) { | |||
5733 | Info.FFDiag(CallLoc); | |||
5734 | return false; | |||
5735 | } | |||
5736 | ||||
5737 | if (!DD || DD->isTrivial() || | |||
5738 | (RD->isAnonymousStructOrUnion() && RD->isUnion())) { | |||
5739 | // A trivial destructor just ends the lifetime of the object. Check for | |||
5740 | // this case before checking for a body, because we might not bother | |||
5741 | // building a body for a trivial destructor. Note that it doesn't matter | |||
5742 | // whether the destructor is constexpr in this case; all trivial | |||
5743 | // destructors are constexpr. | |||
5744 | // | |||
5745 | // If an anonymous union would be destroyed, some enclosing destructor must | |||
5746 | // have been explicitly defined, and the anonymous union destruction should | |||
5747 | // have no effect. | |||
5748 | Value = APValue(); | |||
5749 | return true; | |||
5750 | } | |||
5751 | ||||
5752 | if (!Info.CheckCallLimit(CallLoc)) | |||
5753 | return false; | |||
5754 | ||||
5755 | const FunctionDecl *Definition = nullptr; | |||
5756 | const Stmt *Body = DD->getBody(Definition); | |||
5757 | ||||
5758 | if (!CheckConstexprFunction(Info, CallLoc, DD, Definition, Body)) | |||
5759 | return false; | |||
5760 | ||||
5761 | CallStackFrame Frame(Info, CallLoc, Definition, &This, nullptr); | |||
5762 | ||||
5763 | // We're now in the period of destruction of this object. | |||
5764 | unsigned BasesLeft = RD->getNumBases(); | |||
5765 | EvalInfo::EvaluatingDestructorRAII EvalObj( | |||
5766 | Info, | |||
5767 | ObjectUnderConstruction{This.getLValueBase(), This.Designator.Entries}); | |||
5768 | if (!EvalObj.DidInsert) { | |||
5769 | // C++2a [class.dtor]p19: | |||
5770 | // the behavior is undefined if the destructor is invoked for an object | |||
5771 | // whose lifetime has ended | |||
5772 | // (Note that formally the lifetime ends when the period of destruction | |||
5773 | // begins, even though certain uses of the object remain valid until the | |||
5774 | // period of destruction ends.) | |||
5775 | Info.FFDiag(CallLoc, diag::note_constexpr_double_destroy); | |||
5776 | return false; | |||
5777 | } | |||
5778 | ||||
5779 | // FIXME: Creating an APValue just to hold a nonexistent return value is | |||
5780 | // wasteful. | |||
5781 | APValue RetVal; | |||
5782 | StmtResult Ret = {RetVal, nullptr}; | |||
5783 | if (EvaluateStmt(Ret, Info, Definition->getBody()) == ESR_Failed) | |||
5784 | return false; | |||
5785 | ||||
5786 | // A union destructor does not implicitly destroy its members. | |||
5787 | if (RD->isUnion()) | |||
5788 | return true; | |||
5789 | ||||
5790 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
5791 | ||||
5792 | // We don't have a good way to iterate fields in reverse, so collect all the | |||
5793 | // fields first and then walk them backwards. | |||
5794 | SmallVector<FieldDecl*, 16> Fields(RD->field_begin(), RD->field_end()); | |||
5795 | for (const FieldDecl *FD : llvm::reverse(Fields)) { | |||
5796 | if (FD->isUnnamedBitfield()) | |||
5797 | continue; | |||
5798 | ||||
5799 | LValue Subobject = This; | |||
5800 | if (!HandleLValueMember(Info, &LocE, Subobject, FD, &Layout)) | |||
5801 | return false; | |||
5802 | ||||
5803 | APValue *SubobjectValue = &Value.getStructField(FD->getFieldIndex()); | |||
5804 | if (!HandleDestructionImpl(Info, CallLoc, Subobject, *SubobjectValue, | |||
5805 | FD->getType())) | |||
5806 | return false; | |||
5807 | } | |||
5808 | ||||
5809 | if (BasesLeft != 0) | |||
5810 | EvalObj.startedDestroyingBases(); | |||
5811 | ||||
5812 | // Destroy base classes in reverse order. | |||
5813 | for (const CXXBaseSpecifier &Base : llvm::reverse(RD->bases())) { | |||
5814 | --BasesLeft; | |||
5815 | ||||
5816 | QualType BaseType = Base.getType(); | |||
5817 | LValue Subobject = This; | |||
5818 | if (!HandleLValueDirectBase(Info, &LocE, Subobject, RD, | |||
5819 | BaseType->getAsCXXRecordDecl(), &Layout)) | |||
5820 | return false; | |||
5821 | ||||
5822 | APValue *SubobjectValue = &Value.getStructBase(BasesLeft); | |||
5823 | if (!HandleDestructionImpl(Info, CallLoc, Subobject, *SubobjectValue, | |||
5824 | BaseType)) | |||
5825 | return false; | |||
5826 | } | |||
5827 | assert(BasesLeft == 0 && "NumBases was wrong?")((BasesLeft == 0 && "NumBases was wrong?") ? static_cast <void> (0) : __assert_fail ("BasesLeft == 0 && \"NumBases was wrong?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5827, __PRETTY_FUNCTION__)); | |||
5828 | ||||
5829 | // The period of destruction ends now. The object is gone. | |||
5830 | Value = APValue(); | |||
5831 | return true; | |||
5832 | } | |||
5833 | ||||
5834 | namespace { | |||
5835 | struct DestroyObjectHandler { | |||
5836 | EvalInfo &Info; | |||
5837 | const Expr *E; | |||
5838 | const LValue &This; | |||
5839 | const AccessKinds AccessKind; | |||
5840 | ||||
5841 | typedef bool result_type; | |||
5842 | bool failed() { return false; } | |||
5843 | bool found(APValue &Subobj, QualType SubobjType) { | |||
5844 | return HandleDestructionImpl(Info, E->getExprLoc(), This, Subobj, | |||
5845 | SubobjType); | |||
5846 | } | |||
5847 | bool found(APSInt &Value, QualType SubobjType) { | |||
5848 | Info.FFDiag(E, diag::note_constexpr_destroy_complex_elem); | |||
5849 | return false; | |||
5850 | } | |||
5851 | bool found(APFloat &Value, QualType SubobjType) { | |||
5852 | Info.FFDiag(E, diag::note_constexpr_destroy_complex_elem); | |||
5853 | return false; | |||
5854 | } | |||
5855 | }; | |||
5856 | } | |||
5857 | ||||
5858 | /// Perform a destructor or pseudo-destructor call on the given object, which | |||
5859 | /// might in general not be a complete object. | |||
5860 | static bool HandleDestruction(EvalInfo &Info, const Expr *E, | |||
5861 | const LValue &This, QualType ThisType) { | |||
5862 | CompleteObject Obj = findCompleteObject(Info, E, AK_Destroy, This, ThisType); | |||
5863 | DestroyObjectHandler Handler = {Info, E, This, AK_Destroy}; | |||
5864 | return Obj && findSubobject(Info, E, Obj, This.Designator, Handler); | |||
5865 | } | |||
5866 | ||||
5867 | /// Destroy and end the lifetime of the given complete object. | |||
5868 | static bool HandleDestruction(EvalInfo &Info, SourceLocation Loc, | |||
5869 | APValue::LValueBase LVBase, APValue &Value, | |||
5870 | QualType T) { | |||
5871 | // If we've had an unmodeled side-effect, we can't rely on mutable state | |||
5872 | // (such as the object we're about to destroy) being correct. | |||
5873 | if (Info.EvalStatus.HasSideEffects) | |||
5874 | return false; | |||
5875 | ||||
5876 | LValue LV; | |||
5877 | LV.set({LVBase}); | |||
5878 | return HandleDestructionImpl(Info, Loc, LV, Value, T); | |||
5879 | } | |||
5880 | ||||
5881 | //===----------------------------------------------------------------------===// | |||
5882 | // Generic Evaluation | |||
5883 | //===----------------------------------------------------------------------===// | |||
5884 | namespace { | |||
5885 | ||||
5886 | class BitCastBuffer { | |||
5887 | // FIXME: We're going to need bit-level granularity when we support | |||
5888 | // bit-fields. | |||
5889 | // FIXME: Its possible under the C++ standard for 'char' to not be 8 bits, but | |||
5890 | // we don't support a host or target where that is the case. Still, we should | |||
5891 | // use a more generic type in case we ever do. | |||
5892 | SmallVector<Optional<unsigned char>, 32> Bytes; | |||
5893 | ||||
5894 | static_assert(std::numeric_limits<unsigned char>::digits >= 8, | |||
5895 | "Need at least 8 bit unsigned char"); | |||
5896 | ||||
5897 | bool TargetIsLittleEndian; | |||
5898 | ||||
5899 | public: | |||
5900 | BitCastBuffer(CharUnits Width, bool TargetIsLittleEndian) | |||
5901 | : Bytes(Width.getQuantity()), | |||
5902 | TargetIsLittleEndian(TargetIsLittleEndian) {} | |||
5903 | ||||
5904 | LLVM_NODISCARD[[clang::warn_unused_result]] | |||
5905 | bool readObject(CharUnits Offset, CharUnits Width, | |||
5906 | SmallVectorImpl<unsigned char> &Output) const { | |||
5907 | for (CharUnits I = Offset, E = Offset + Width; I != E; ++I) { | |||
5908 | // If a byte of an integer is uninitialized, then the whole integer is | |||
5909 | // uninitalized. | |||
5910 | if (!Bytes[I.getQuantity()]) | |||
5911 | return false; | |||
5912 | Output.push_back(*Bytes[I.getQuantity()]); | |||
5913 | } | |||
5914 | if (llvm::sys::IsLittleEndianHost != TargetIsLittleEndian) | |||
5915 | std::reverse(Output.begin(), Output.end()); | |||
5916 | return true; | |||
5917 | } | |||
5918 | ||||
5919 | void writeObject(CharUnits Offset, SmallVectorImpl<unsigned char> &Input) { | |||
5920 | if (llvm::sys::IsLittleEndianHost != TargetIsLittleEndian) | |||
5921 | std::reverse(Input.begin(), Input.end()); | |||
5922 | ||||
5923 | size_t Index = 0; | |||
5924 | for (unsigned char Byte : Input) { | |||
5925 | assert(!Bytes[Offset.getQuantity() + Index] && "overwriting a byte?")((!Bytes[Offset.getQuantity() + Index] && "overwriting a byte?" ) ? static_cast<void> (0) : __assert_fail ("!Bytes[Offset.getQuantity() + Index] && \"overwriting a byte?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5925, __PRETTY_FUNCTION__)); | |||
5926 | Bytes[Offset.getQuantity() + Index] = Byte; | |||
5927 | ++Index; | |||
5928 | } | |||
5929 | } | |||
5930 | ||||
5931 | size_t size() { return Bytes.size(); } | |||
5932 | }; | |||
5933 | ||||
5934 | /// Traverse an APValue to produce an BitCastBuffer, emulating how the current | |||
5935 | /// target would represent the value at runtime. | |||
5936 | class APValueToBufferConverter { | |||
5937 | EvalInfo &Info; | |||
5938 | BitCastBuffer Buffer; | |||
5939 | const CastExpr *BCE; | |||
5940 | ||||
5941 | APValueToBufferConverter(EvalInfo &Info, CharUnits ObjectWidth, | |||
5942 | const CastExpr *BCE) | |||
5943 | : Info(Info), | |||
5944 | Buffer(ObjectWidth, Info.Ctx.getTargetInfo().isLittleEndian()), | |||
5945 | BCE(BCE) {} | |||
5946 | ||||
5947 | bool visit(const APValue &Val, QualType Ty) { | |||
5948 | return visit(Val, Ty, CharUnits::fromQuantity(0)); | |||
5949 | } | |||
5950 | ||||
5951 | // Write out Val with type Ty into Buffer starting at Offset. | |||
5952 | bool visit(const APValue &Val, QualType Ty, CharUnits Offset) { | |||
5953 | assert((size_t)Offset.getQuantity() <= Buffer.size())(((size_t)Offset.getQuantity() <= Buffer.size()) ? static_cast <void> (0) : __assert_fail ("(size_t)Offset.getQuantity() <= Buffer.size()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5953, __PRETTY_FUNCTION__)); | |||
5954 | ||||
5955 | // As a special case, nullptr_t has an indeterminate value. | |||
5956 | if (Ty->isNullPtrType()) | |||
5957 | return true; | |||
5958 | ||||
5959 | // Dig through Src to find the byte at SrcOffset. | |||
5960 | switch (Val.getKind()) { | |||
5961 | case APValue::Indeterminate: | |||
5962 | case APValue::None: | |||
5963 | return true; | |||
5964 | ||||
5965 | case APValue::Int: | |||
5966 | return visitInt(Val.getInt(), Ty, Offset); | |||
5967 | case APValue::Float: | |||
5968 | return visitFloat(Val.getFloat(), Ty, Offset); | |||
5969 | case APValue::Array: | |||
5970 | return visitArray(Val, Ty, Offset); | |||
5971 | case APValue::Struct: | |||
5972 | return visitRecord(Val, Ty, Offset); | |||
5973 | ||||
5974 | case APValue::ComplexInt: | |||
5975 | case APValue::ComplexFloat: | |||
5976 | case APValue::Vector: | |||
5977 | case APValue::FixedPoint: | |||
5978 | // FIXME: We should support these. | |||
5979 | ||||
5980 | case APValue::Union: | |||
5981 | case APValue::MemberPointer: | |||
5982 | case APValue::AddrLabelDiff: { | |||
5983 | Info.FFDiag(BCE->getBeginLoc(), | |||
5984 | diag::note_constexpr_bit_cast_unsupported_type) | |||
5985 | << Ty; | |||
5986 | return false; | |||
5987 | } | |||
5988 | ||||
5989 | case APValue::LValue: | |||
5990 | llvm_unreachable("LValue subobject in bit_cast?")::llvm::llvm_unreachable_internal("LValue subobject in bit_cast?" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5990); | |||
5991 | } | |||
5992 | llvm_unreachable("Unhandled APValue::ValueKind")::llvm::llvm_unreachable_internal("Unhandled APValue::ValueKind" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 5992); | |||
5993 | } | |||
5994 | ||||
5995 | bool visitRecord(const APValue &Val, QualType Ty, CharUnits Offset) { | |||
5996 | const RecordDecl *RD = Ty->getAsRecordDecl(); | |||
5997 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
5998 | ||||
5999 | // Visit the base classes. | |||
6000 | if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) { | |||
6001 | for (size_t I = 0, E = CXXRD->getNumBases(); I != E; ++I) { | |||
6002 | const CXXBaseSpecifier &BS = CXXRD->bases_begin()[I]; | |||
6003 | CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl(); | |||
6004 | ||||
6005 | if (!visitRecord(Val.getStructBase(I), BS.getType(), | |||
6006 | Layout.getBaseClassOffset(BaseDecl) + Offset)) | |||
6007 | return false; | |||
6008 | } | |||
6009 | } | |||
6010 | ||||
6011 | // Visit the fields. | |||
6012 | unsigned FieldIdx = 0; | |||
6013 | for (FieldDecl *FD : RD->fields()) { | |||
6014 | if (FD->isBitField()) { | |||
6015 | Info.FFDiag(BCE->getBeginLoc(), | |||
6016 | diag::note_constexpr_bit_cast_unsupported_bitfield); | |||
6017 | return false; | |||
6018 | } | |||
6019 | ||||
6020 | uint64_t FieldOffsetBits = Layout.getFieldOffset(FieldIdx); | |||
6021 | ||||
6022 | assert(FieldOffsetBits % Info.Ctx.getCharWidth() == 0 &&((FieldOffsetBits % Info.Ctx.getCharWidth() == 0 && "only bit-fields can have sub-char alignment" ) ? static_cast<void> (0) : __assert_fail ("FieldOffsetBits % Info.Ctx.getCharWidth() == 0 && \"only bit-fields can have sub-char alignment\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6023, __PRETTY_FUNCTION__)) | |||
6023 | "only bit-fields can have sub-char alignment")((FieldOffsetBits % Info.Ctx.getCharWidth() == 0 && "only bit-fields can have sub-char alignment" ) ? static_cast<void> (0) : __assert_fail ("FieldOffsetBits % Info.Ctx.getCharWidth() == 0 && \"only bit-fields can have sub-char alignment\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6023, __PRETTY_FUNCTION__)); | |||
6024 | CharUnits FieldOffset = | |||
6025 | Info.Ctx.toCharUnitsFromBits(FieldOffsetBits) + Offset; | |||
6026 | QualType FieldTy = FD->getType(); | |||
6027 | if (!visit(Val.getStructField(FieldIdx), FieldTy, FieldOffset)) | |||
6028 | return false; | |||
6029 | ++FieldIdx; | |||
6030 | } | |||
6031 | ||||
6032 | return true; | |||
6033 | } | |||
6034 | ||||
6035 | bool visitArray(const APValue &Val, QualType Ty, CharUnits Offset) { | |||
6036 | const auto *CAT = | |||
6037 | dyn_cast_or_null<ConstantArrayType>(Ty->getAsArrayTypeUnsafe()); | |||
6038 | if (!CAT) | |||
6039 | return false; | |||
6040 | ||||
6041 | CharUnits ElemWidth = Info.Ctx.getTypeSizeInChars(CAT->getElementType()); | |||
6042 | unsigned NumInitializedElts = Val.getArrayInitializedElts(); | |||
6043 | unsigned ArraySize = Val.getArraySize(); | |||
6044 | // First, initialize the initialized elements. | |||
6045 | for (unsigned I = 0; I != NumInitializedElts; ++I) { | |||
6046 | const APValue &SubObj = Val.getArrayInitializedElt(I); | |||
6047 | if (!visit(SubObj, CAT->getElementType(), Offset + I * ElemWidth)) | |||
6048 | return false; | |||
6049 | } | |||
6050 | ||||
6051 | // Next, initialize the rest of the array using the filler. | |||
6052 | if (Val.hasArrayFiller()) { | |||
6053 | const APValue &Filler = Val.getArrayFiller(); | |||
6054 | for (unsigned I = NumInitializedElts; I != ArraySize; ++I) { | |||
6055 | if (!visit(Filler, CAT->getElementType(), Offset + I * ElemWidth)) | |||
6056 | return false; | |||
6057 | } | |||
6058 | } | |||
6059 | ||||
6060 | return true; | |||
6061 | } | |||
6062 | ||||
6063 | bool visitInt(const APSInt &Val, QualType Ty, CharUnits Offset) { | |||
6064 | CharUnits Width = Info.Ctx.getTypeSizeInChars(Ty); | |||
6065 | SmallVector<unsigned char, 8> Bytes(Width.getQuantity()); | |||
6066 | llvm::StoreIntToMemory(Val, &*Bytes.begin(), Width.getQuantity()); | |||
6067 | Buffer.writeObject(Offset, Bytes); | |||
6068 | return true; | |||
6069 | } | |||
6070 | ||||
6071 | bool visitFloat(const APFloat &Val, QualType Ty, CharUnits Offset) { | |||
6072 | APSInt AsInt(Val.bitcastToAPInt()); | |||
6073 | return visitInt(AsInt, Ty, Offset); | |||
6074 | } | |||
6075 | ||||
6076 | public: | |||
6077 | static Optional<BitCastBuffer> convert(EvalInfo &Info, const APValue &Src, | |||
6078 | const CastExpr *BCE) { | |||
6079 | CharUnits DstSize = Info.Ctx.getTypeSizeInChars(BCE->getType()); | |||
6080 | APValueToBufferConverter Converter(Info, DstSize, BCE); | |||
6081 | if (!Converter.visit(Src, BCE->getSubExpr()->getType())) | |||
6082 | return None; | |||
6083 | return Converter.Buffer; | |||
6084 | } | |||
6085 | }; | |||
6086 | ||||
6087 | /// Write an BitCastBuffer into an APValue. | |||
6088 | class BufferToAPValueConverter { | |||
6089 | EvalInfo &Info; | |||
6090 | const BitCastBuffer &Buffer; | |||
6091 | const CastExpr *BCE; | |||
6092 | ||||
6093 | BufferToAPValueConverter(EvalInfo &Info, const BitCastBuffer &Buffer, | |||
6094 | const CastExpr *BCE) | |||
6095 | : Info(Info), Buffer(Buffer), BCE(BCE) {} | |||
6096 | ||||
6097 | // Emit an unsupported bit_cast type error. Sema refuses to build a bit_cast | |||
6098 | // with an invalid type, so anything left is a deficiency on our part (FIXME). | |||
6099 | // Ideally this will be unreachable. | |||
6100 | llvm::NoneType unsupportedType(QualType Ty) { | |||
6101 | Info.FFDiag(BCE->getBeginLoc(), | |||
6102 | diag::note_constexpr_bit_cast_unsupported_type) | |||
6103 | << Ty; | |||
6104 | return None; | |||
6105 | } | |||
6106 | ||||
6107 | Optional<APValue> visit(const BuiltinType *T, CharUnits Offset, | |||
6108 | const EnumType *EnumSugar = nullptr) { | |||
6109 | if (T->isNullPtrType()) { | |||
6110 | uint64_t NullValue = Info.Ctx.getTargetNullPointerValue(QualType(T, 0)); | |||
6111 | return APValue((Expr *)nullptr, | |||
6112 | /*Offset=*/CharUnits::fromQuantity(NullValue), | |||
6113 | APValue::NoLValuePath{}, /*IsNullPtr=*/true); | |||
6114 | } | |||
6115 | ||||
6116 | CharUnits SizeOf = Info.Ctx.getTypeSizeInChars(T); | |||
6117 | SmallVector<uint8_t, 8> Bytes; | |||
6118 | if (!Buffer.readObject(Offset, SizeOf, Bytes)) { | |||
6119 | // If this is std::byte or unsigned char, then its okay to store an | |||
6120 | // indeterminate value. | |||
6121 | bool IsStdByte = EnumSugar && EnumSugar->isStdByteType(); | |||
6122 | bool IsUChar = | |||
6123 | !EnumSugar && (T->isSpecificBuiltinType(BuiltinType::UChar) || | |||
6124 | T->isSpecificBuiltinType(BuiltinType::Char_U)); | |||
6125 | if (!IsStdByte && !IsUChar) { | |||
6126 | QualType DisplayType(EnumSugar ? (const Type *)EnumSugar : T, 0); | |||
6127 | Info.FFDiag(BCE->getExprLoc(), | |||
6128 | diag::note_constexpr_bit_cast_indet_dest) | |||
6129 | << DisplayType << Info.Ctx.getLangOpts().CharIsSigned; | |||
6130 | return None; | |||
6131 | } | |||
6132 | ||||
6133 | return APValue::IndeterminateValue(); | |||
6134 | } | |||
6135 | ||||
6136 | APSInt Val(SizeOf.getQuantity() * Info.Ctx.getCharWidth(), true); | |||
6137 | llvm::LoadIntFromMemory(Val, &*Bytes.begin(), Bytes.size()); | |||
6138 | ||||
6139 | if (T->isIntegralOrEnumerationType()) { | |||
6140 | Val.setIsSigned(T->isSignedIntegerOrEnumerationType()); | |||
6141 | return APValue(Val); | |||
6142 | } | |||
6143 | ||||
6144 | if (T->isRealFloatingType()) { | |||
6145 | const llvm::fltSemantics &Semantics = | |||
6146 | Info.Ctx.getFloatTypeSemantics(QualType(T, 0)); | |||
6147 | return APValue(APFloat(Semantics, Val)); | |||
6148 | } | |||
6149 | ||||
6150 | return unsupportedType(QualType(T, 0)); | |||
6151 | } | |||
6152 | ||||
6153 | Optional<APValue> visit(const RecordType *RTy, CharUnits Offset) { | |||
6154 | const RecordDecl *RD = RTy->getAsRecordDecl(); | |||
6155 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
6156 | ||||
6157 | unsigned NumBases = 0; | |||
6158 | if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) | |||
6159 | NumBases = CXXRD->getNumBases(); | |||
6160 | ||||
6161 | APValue ResultVal(APValue::UninitStruct(), NumBases, | |||
6162 | std::distance(RD->field_begin(), RD->field_end())); | |||
6163 | ||||
6164 | // Visit the base classes. | |||
6165 | if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) { | |||
6166 | for (size_t I = 0, E = CXXRD->getNumBases(); I != E; ++I) { | |||
6167 | const CXXBaseSpecifier &BS = CXXRD->bases_begin()[I]; | |||
6168 | CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl(); | |||
6169 | if (BaseDecl->isEmpty() || | |||
6170 | Info.Ctx.getASTRecordLayout(BaseDecl).getNonVirtualSize().isZero()) | |||
6171 | continue; | |||
6172 | ||||
6173 | Optional<APValue> SubObj = visitType( | |||
6174 | BS.getType(), Layout.getBaseClassOffset(BaseDecl) + Offset); | |||
6175 | if (!SubObj) | |||
6176 | return None; | |||
6177 | ResultVal.getStructBase(I) = *SubObj; | |||
6178 | } | |||
6179 | } | |||
6180 | ||||
6181 | // Visit the fields. | |||
6182 | unsigned FieldIdx = 0; | |||
6183 | for (FieldDecl *FD : RD->fields()) { | |||
6184 | // FIXME: We don't currently support bit-fields. A lot of the logic for | |||
6185 | // this is in CodeGen, so we need to factor it around. | |||
6186 | if (FD->isBitField()) { | |||
6187 | Info.FFDiag(BCE->getBeginLoc(), | |||
6188 | diag::note_constexpr_bit_cast_unsupported_bitfield); | |||
6189 | return None; | |||
6190 | } | |||
6191 | ||||
6192 | uint64_t FieldOffsetBits = Layout.getFieldOffset(FieldIdx); | |||
6193 | assert(FieldOffsetBits % Info.Ctx.getCharWidth() == 0)((FieldOffsetBits % Info.Ctx.getCharWidth() == 0) ? static_cast <void> (0) : __assert_fail ("FieldOffsetBits % Info.Ctx.getCharWidth() == 0" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6193, __PRETTY_FUNCTION__)); | |||
6194 | ||||
6195 | CharUnits FieldOffset = | |||
6196 | CharUnits::fromQuantity(FieldOffsetBits / Info.Ctx.getCharWidth()) + | |||
6197 | Offset; | |||
6198 | QualType FieldTy = FD->getType(); | |||
6199 | Optional<APValue> SubObj = visitType(FieldTy, FieldOffset); | |||
6200 | if (!SubObj) | |||
6201 | return None; | |||
6202 | ResultVal.getStructField(FieldIdx) = *SubObj; | |||
6203 | ++FieldIdx; | |||
6204 | } | |||
6205 | ||||
6206 | return ResultVal; | |||
6207 | } | |||
6208 | ||||
6209 | Optional<APValue> visit(const EnumType *Ty, CharUnits Offset) { | |||
6210 | QualType RepresentationType = Ty->getDecl()->getIntegerType(); | |||
6211 | assert(!RepresentationType.isNull() &&((!RepresentationType.isNull() && "enum forward decl should be caught by Sema" ) ? static_cast<void> (0) : __assert_fail ("!RepresentationType.isNull() && \"enum forward decl should be caught by Sema\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6212, __PRETTY_FUNCTION__)) | |||
6212 | "enum forward decl should be caught by Sema")((!RepresentationType.isNull() && "enum forward decl should be caught by Sema" ) ? static_cast<void> (0) : __assert_fail ("!RepresentationType.isNull() && \"enum forward decl should be caught by Sema\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6212, __PRETTY_FUNCTION__)); | |||
6213 | const BuiltinType *AsBuiltin = | |||
6214 | RepresentationType.getCanonicalType()->getAs<BuiltinType>(); | |||
6215 | assert(AsBuiltin && "non-integral enum underlying type?")((AsBuiltin && "non-integral enum underlying type?") ? static_cast<void> (0) : __assert_fail ("AsBuiltin && \"non-integral enum underlying type?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6215, __PRETTY_FUNCTION__)); | |||
6216 | // Recurse into the underlying type. Treat std::byte transparently as | |||
6217 | // unsigned char. | |||
6218 | return visit(AsBuiltin, Offset, /*EnumTy=*/Ty); | |||
6219 | } | |||
6220 | ||||
6221 | Optional<APValue> visit(const ConstantArrayType *Ty, CharUnits Offset) { | |||
6222 | size_t Size = Ty->getSize().getLimitedValue(); | |||
6223 | CharUnits ElementWidth = Info.Ctx.getTypeSizeInChars(Ty->getElementType()); | |||
6224 | ||||
6225 | APValue ArrayValue(APValue::UninitArray(), Size, Size); | |||
6226 | for (size_t I = 0; I != Size; ++I) { | |||
6227 | Optional<APValue> ElementValue = | |||
6228 | visitType(Ty->getElementType(), Offset + I * ElementWidth); | |||
6229 | if (!ElementValue) | |||
6230 | return None; | |||
6231 | ArrayValue.getArrayInitializedElt(I) = std::move(*ElementValue); | |||
6232 | } | |||
6233 | ||||
6234 | return ArrayValue; | |||
6235 | } | |||
6236 | ||||
6237 | Optional<APValue> visit(const Type *Ty, CharUnits Offset) { | |||
6238 | return unsupportedType(QualType(Ty, 0)); | |||
6239 | } | |||
6240 | ||||
6241 | Optional<APValue> visitType(QualType Ty, CharUnits Offset) { | |||
6242 | QualType Can = Ty.getCanonicalType(); | |||
6243 | ||||
6244 | switch (Can->getTypeClass()) { | |||
6245 | #define TYPE(Class, Base) \ | |||
6246 | case Type::Class: \ | |||
6247 | return visit(cast<Class##Type>(Can.getTypePtr()), Offset); | |||
6248 | #define ABSTRACT_TYPE(Class, Base) | |||
6249 | #define NON_CANONICAL_TYPE(Class, Base) \ | |||
6250 | case Type::Class: \ | |||
6251 | llvm_unreachable("non-canonical type should be impossible!")::llvm::llvm_unreachable_internal("non-canonical type should be impossible!" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6251); | |||
6252 | #define DEPENDENT_TYPE(Class, Base) \ | |||
6253 | case Type::Class: \ | |||
6254 | llvm_unreachable( \::llvm::llvm_unreachable_internal("dependent types aren't supported in the constant evaluator!" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6255) | |||
6255 | "dependent types aren't supported in the constant evaluator!")::llvm::llvm_unreachable_internal("dependent types aren't supported in the constant evaluator!" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6255); | |||
6256 | #define NON_CANONICAL_UNLESS_DEPENDENT(Class, Base)case Type::Class: ::llvm::llvm_unreachable_internal("either dependent or not canonical!" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6256); \ | |||
6257 | case Type::Class: \ | |||
6258 | llvm_unreachable("either dependent or not canonical!")::llvm::llvm_unreachable_internal("either dependent or not canonical!" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6258); | |||
6259 | #include "clang/AST/TypeNodes.inc" | |||
6260 | } | |||
6261 | llvm_unreachable("Unhandled Type::TypeClass")::llvm::llvm_unreachable_internal("Unhandled Type::TypeClass" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6261); | |||
6262 | } | |||
6263 | ||||
6264 | public: | |||
6265 | // Pull out a full value of type DstType. | |||
6266 | static Optional<APValue> convert(EvalInfo &Info, BitCastBuffer &Buffer, | |||
6267 | const CastExpr *BCE) { | |||
6268 | BufferToAPValueConverter Converter(Info, Buffer, BCE); | |||
6269 | return Converter.visitType(BCE->getType(), CharUnits::fromQuantity(0)); | |||
6270 | } | |||
6271 | }; | |||
6272 | ||||
6273 | static bool checkBitCastConstexprEligibilityType(SourceLocation Loc, | |||
6274 | QualType Ty, EvalInfo *Info, | |||
6275 | const ASTContext &Ctx, | |||
6276 | bool CheckingDest) { | |||
6277 | Ty = Ty.getCanonicalType(); | |||
6278 | ||||
6279 | auto diag = [&](int Reason) { | |||
6280 | if (Info) | |||
6281 | Info->FFDiag(Loc, diag::note_constexpr_bit_cast_invalid_type) | |||
6282 | << CheckingDest << (Reason == 4) << Reason; | |||
6283 | return false; | |||
6284 | }; | |||
6285 | auto note = [&](int Construct, QualType NoteTy, SourceLocation NoteLoc) { | |||
6286 | if (Info) | |||
6287 | Info->Note(NoteLoc, diag::note_constexpr_bit_cast_invalid_subtype) | |||
6288 | << NoteTy << Construct << Ty; | |||
6289 | return false; | |||
6290 | }; | |||
6291 | ||||
6292 | if (Ty->isUnionType()) | |||
6293 | return diag(0); | |||
6294 | if (Ty->isPointerType()) | |||
6295 | return diag(1); | |||
6296 | if (Ty->isMemberPointerType()) | |||
6297 | return diag(2); | |||
6298 | if (Ty.isVolatileQualified()) | |||
6299 | return diag(3); | |||
6300 | ||||
6301 | if (RecordDecl *Record = Ty->getAsRecordDecl()) { | |||
6302 | if (auto *CXXRD = dyn_cast<CXXRecordDecl>(Record)) { | |||
6303 | for (CXXBaseSpecifier &BS : CXXRD->bases()) | |||
6304 | if (!checkBitCastConstexprEligibilityType(Loc, BS.getType(), Info, Ctx, | |||
6305 | CheckingDest)) | |||
6306 | return note(1, BS.getType(), BS.getBeginLoc()); | |||
6307 | } | |||
6308 | for (FieldDecl *FD : Record->fields()) { | |||
6309 | if (FD->getType()->isReferenceType()) | |||
6310 | return diag(4); | |||
6311 | if (!checkBitCastConstexprEligibilityType(Loc, FD->getType(), Info, Ctx, | |||
6312 | CheckingDest)) | |||
6313 | return note(0, FD->getType(), FD->getBeginLoc()); | |||
6314 | } | |||
6315 | } | |||
6316 | ||||
6317 | if (Ty->isArrayType() && | |||
6318 | !checkBitCastConstexprEligibilityType(Loc, Ctx.getBaseElementType(Ty), | |||
6319 | Info, Ctx, CheckingDest)) | |||
6320 | return false; | |||
6321 | ||||
6322 | return true; | |||
6323 | } | |||
6324 | ||||
6325 | static bool checkBitCastConstexprEligibility(EvalInfo *Info, | |||
6326 | const ASTContext &Ctx, | |||
6327 | const CastExpr *BCE) { | |||
6328 | bool DestOK = checkBitCastConstexprEligibilityType( | |||
6329 | BCE->getBeginLoc(), BCE->getType(), Info, Ctx, true); | |||
6330 | bool SourceOK = DestOK && checkBitCastConstexprEligibilityType( | |||
6331 | BCE->getBeginLoc(), | |||
6332 | BCE->getSubExpr()->getType(), Info, Ctx, false); | |||
6333 | return SourceOK; | |||
6334 | } | |||
6335 | ||||
6336 | static bool handleLValueToRValueBitCast(EvalInfo &Info, APValue &DestValue, | |||
6337 | APValue &SourceValue, | |||
6338 | const CastExpr *BCE) { | |||
6339 | assert(CHAR_BIT == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 &&((8 == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 && "no host or target supports non 8-bit chars") ? static_cast<void> (0) : __assert_fail ("CHAR_BIT == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 && \"no host or target supports non 8-bit chars\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6340, __PRETTY_FUNCTION__)) | |||
6340 | "no host or target supports non 8-bit chars")((8 == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 && "no host or target supports non 8-bit chars") ? static_cast<void> (0) : __assert_fail ("CHAR_BIT == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 && \"no host or target supports non 8-bit chars\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6340, __PRETTY_FUNCTION__)); | |||
6341 | assert(SourceValue.isLValue() &&((SourceValue.isLValue() && "LValueToRValueBitcast requires an lvalue operand!" ) ? static_cast<void> (0) : __assert_fail ("SourceValue.isLValue() && \"LValueToRValueBitcast requires an lvalue operand!\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6342, __PRETTY_FUNCTION__)) | |||
6342 | "LValueToRValueBitcast requires an lvalue operand!")((SourceValue.isLValue() && "LValueToRValueBitcast requires an lvalue operand!" ) ? static_cast<void> (0) : __assert_fail ("SourceValue.isLValue() && \"LValueToRValueBitcast requires an lvalue operand!\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6342, __PRETTY_FUNCTION__)); | |||
6343 | ||||
6344 | if (!checkBitCastConstexprEligibility(&Info, Info.Ctx, BCE)) | |||
6345 | return false; | |||
6346 | ||||
6347 | LValue SourceLValue; | |||
6348 | APValue SourceRValue; | |||
6349 | SourceLValue.setFrom(Info.Ctx, SourceValue); | |||
6350 | if (!handleLValueToRValueConversion( | |||
6351 | Info, BCE, BCE->getSubExpr()->getType().withConst(), SourceLValue, | |||
6352 | SourceRValue, /*WantObjectRepresentation=*/true)) | |||
6353 | return false; | |||
6354 | ||||
6355 | // Read out SourceValue into a char buffer. | |||
6356 | Optional<BitCastBuffer> Buffer = | |||
6357 | APValueToBufferConverter::convert(Info, SourceRValue, BCE); | |||
6358 | if (!Buffer) | |||
6359 | return false; | |||
6360 | ||||
6361 | // Write out the buffer into a new APValue. | |||
6362 | Optional<APValue> MaybeDestValue = | |||
6363 | BufferToAPValueConverter::convert(Info, *Buffer, BCE); | |||
6364 | if (!MaybeDestValue) | |||
6365 | return false; | |||
6366 | ||||
6367 | DestValue = std::move(*MaybeDestValue); | |||
6368 | return true; | |||
6369 | } | |||
6370 | ||||
6371 | template <class Derived> | |||
6372 | class ExprEvaluatorBase | |||
6373 | : public ConstStmtVisitor<Derived, bool> { | |||
6374 | private: | |||
6375 | Derived &getDerived() { return static_cast<Derived&>(*this); } | |||
6376 | bool DerivedSuccess(const APValue &V, const Expr *E) { | |||
6377 | return getDerived().Success(V, E); | |||
6378 | } | |||
6379 | bool DerivedZeroInitialization(const Expr *E) { | |||
6380 | return getDerived().ZeroInitialization(E); | |||
6381 | } | |||
6382 | ||||
6383 | // Check whether a conditional operator with a non-constant condition is a | |||
6384 | // potential constant expression. If neither arm is a potential constant | |||
6385 | // expression, then the conditional operator is not either. | |||
6386 | template<typename ConditionalOperator> | |||
6387 | void CheckPotentialConstantConditional(const ConditionalOperator *E) { | |||
6388 | assert(Info.checkingPotentialConstantExpression())((Info.checkingPotentialConstantExpression()) ? static_cast< void> (0) : __assert_fail ("Info.checkingPotentialConstantExpression()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6388, __PRETTY_FUNCTION__)); | |||
6389 | ||||
6390 | // Speculatively evaluate both arms. | |||
6391 | SmallVector<PartialDiagnosticAt, 8> Diag; | |||
6392 | { | |||
6393 | SpeculativeEvaluationRAII Speculate(Info, &Diag); | |||
6394 | StmtVisitorTy::Visit(E->getFalseExpr()); | |||
6395 | if (Diag.empty()) | |||
6396 | return; | |||
6397 | } | |||
6398 | ||||
6399 | { | |||
6400 | SpeculativeEvaluationRAII Speculate(Info, &Diag); | |||
6401 | Diag.clear(); | |||
6402 | StmtVisitorTy::Visit(E->getTrueExpr()); | |||
6403 | if (Diag.empty()) | |||
6404 | return; | |||
6405 | } | |||
6406 | ||||
6407 | Error(E, diag::note_constexpr_conditional_never_const); | |||
6408 | } | |||
6409 | ||||
6410 | ||||
6411 | template<typename ConditionalOperator> | |||
6412 | bool HandleConditionalOperator(const ConditionalOperator *E) { | |||
6413 | bool BoolResult; | |||
6414 | if (!EvaluateAsBooleanCondition(E->getCond(), BoolResult, Info)) { | |||
6415 | if (Info.checkingPotentialConstantExpression() && Info.noteFailure()) { | |||
6416 | CheckPotentialConstantConditional(E); | |||
6417 | return false; | |||
6418 | } | |||
6419 | if (Info.noteFailure()) { | |||
6420 | StmtVisitorTy::Visit(E->getTrueExpr()); | |||
6421 | StmtVisitorTy::Visit(E->getFalseExpr()); | |||
6422 | } | |||
6423 | return false; | |||
6424 | } | |||
6425 | ||||
6426 | Expr *EvalExpr = BoolResult ? E->getTrueExpr() : E->getFalseExpr(); | |||
6427 | return StmtVisitorTy::Visit(EvalExpr); | |||
6428 | } | |||
6429 | ||||
6430 | protected: | |||
6431 | EvalInfo &Info; | |||
6432 | typedef ConstStmtVisitor<Derived, bool> StmtVisitorTy; | |||
6433 | typedef ExprEvaluatorBase ExprEvaluatorBaseTy; | |||
6434 | ||||
6435 | OptionalDiagnostic CCEDiag(const Expr *E, diag::kind D) { | |||
6436 | return Info.CCEDiag(E, D); | |||
6437 | } | |||
6438 | ||||
6439 | bool ZeroInitialization(const Expr *E) { return Error(E); } | |||
6440 | ||||
6441 | public: | |||
6442 | ExprEvaluatorBase(EvalInfo &Info) : Info(Info) {} | |||
6443 | ||||
6444 | EvalInfo &getEvalInfo() { return Info; } | |||
6445 | ||||
6446 | /// Report an evaluation error. This should only be called when an error is | |||
6447 | /// first discovered. When propagating an error, just return false. | |||
6448 | bool Error(const Expr *E, diag::kind D) { | |||
6449 | Info.FFDiag(E, D); | |||
6450 | return false; | |||
6451 | } | |||
6452 | bool Error(const Expr *E) { | |||
6453 | return Error(E, diag::note_invalid_subexpr_in_const_expr); | |||
6454 | } | |||
6455 | ||||
6456 | bool VisitStmt(const Stmt *) { | |||
6457 | llvm_unreachable("Expression evaluator should not be called on stmts")::llvm::llvm_unreachable_internal("Expression evaluator should not be called on stmts" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6457); | |||
6458 | } | |||
6459 | bool VisitExpr(const Expr *E) { | |||
6460 | return Error(E); | |||
6461 | } | |||
6462 | ||||
6463 | bool VisitConstantExpr(const ConstantExpr *E) | |||
6464 | { return StmtVisitorTy::Visit(E->getSubExpr()); } | |||
6465 | bool VisitParenExpr(const ParenExpr *E) | |||
6466 | { return StmtVisitorTy::Visit(E->getSubExpr()); } | |||
6467 | bool VisitUnaryExtension(const UnaryOperator *E) | |||
6468 | { return StmtVisitorTy::Visit(E->getSubExpr()); } | |||
6469 | bool VisitUnaryPlus(const UnaryOperator *E) | |||
6470 | { return StmtVisitorTy::Visit(E->getSubExpr()); } | |||
6471 | bool VisitChooseExpr(const ChooseExpr *E) | |||
6472 | { return StmtVisitorTy::Visit(E->getChosenSubExpr()); } | |||
6473 | bool VisitGenericSelectionExpr(const GenericSelectionExpr *E) | |||
6474 | { return StmtVisitorTy::Visit(E->getResultExpr()); } | |||
6475 | bool VisitSubstNonTypeTemplateParmExpr(const SubstNonTypeTemplateParmExpr *E) | |||
6476 | { return StmtVisitorTy::Visit(E->getReplacement()); } | |||
6477 | bool VisitCXXDefaultArgExpr(const CXXDefaultArgExpr *E) { | |||
6478 | TempVersionRAII RAII(*Info.CurrentCall); | |||
6479 | SourceLocExprScopeGuard Guard(E, Info.CurrentCall->CurSourceLocExprScope); | |||
6480 | return StmtVisitorTy::Visit(E->getExpr()); | |||
6481 | } | |||
6482 | bool VisitCXXDefaultInitExpr(const CXXDefaultInitExpr *E) { | |||
6483 | TempVersionRAII RAII(*Info.CurrentCall); | |||
6484 | // The initializer may not have been parsed yet, or might be erroneous. | |||
6485 | if (!E->getExpr()) | |||
6486 | return Error(E); | |||
6487 | SourceLocExprScopeGuard Guard(E, Info.CurrentCall->CurSourceLocExprScope); | |||
6488 | return StmtVisitorTy::Visit(E->getExpr()); | |||
6489 | } | |||
6490 | ||||
6491 | bool VisitExprWithCleanups(const ExprWithCleanups *E) { | |||
6492 | FullExpressionRAII Scope(Info); | |||
6493 | return StmtVisitorTy::Visit(E->getSubExpr()) && Scope.destroy(); | |||
6494 | } | |||
6495 | ||||
6496 | // Temporaries are registered when created, so we don't care about | |||
6497 | // CXXBindTemporaryExpr. | |||
6498 | bool VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *E) { | |||
6499 | return StmtVisitorTy::Visit(E->getSubExpr()); | |||
6500 | } | |||
6501 | ||||
6502 | bool VisitCXXReinterpretCastExpr(const CXXReinterpretCastExpr *E) { | |||
6503 | CCEDiag(E, diag::note_constexpr_invalid_cast) << 0; | |||
6504 | return static_cast<Derived*>(this)->VisitCastExpr(E); | |||
| ||||
6505 | } | |||
6506 | bool VisitCXXDynamicCastExpr(const CXXDynamicCastExpr *E) { | |||
6507 | if (!Info.Ctx.getLangOpts().CPlusPlus2a) | |||
6508 | CCEDiag(E, diag::note_constexpr_invalid_cast) << 1; | |||
6509 | return static_cast<Derived*>(this)->VisitCastExpr(E); | |||
6510 | } | |||
6511 | bool VisitBuiltinBitCastExpr(const BuiltinBitCastExpr *E) { | |||
6512 | return static_cast<Derived*>(this)->VisitCastExpr(E); | |||
6513 | } | |||
6514 | ||||
6515 | bool VisitBinaryOperator(const BinaryOperator *E) { | |||
6516 | switch (E->getOpcode()) { | |||
6517 | default: | |||
6518 | return Error(E); | |||
6519 | ||||
6520 | case BO_Comma: | |||
6521 | VisitIgnoredValue(E->getLHS()); | |||
6522 | return StmtVisitorTy::Visit(E->getRHS()); | |||
6523 | ||||
6524 | case BO_PtrMemD: | |||
6525 | case BO_PtrMemI: { | |||
6526 | LValue Obj; | |||
6527 | if (!HandleMemberPointerAccess(Info, E, Obj)) | |||
6528 | return false; | |||
6529 | APValue Result; | |||
6530 | if (!handleLValueToRValueConversion(Info, E, E->getType(), Obj, Result)) | |||
6531 | return false; | |||
6532 | return DerivedSuccess(Result, E); | |||
6533 | } | |||
6534 | } | |||
6535 | } | |||
6536 | ||||
6537 | bool VisitBinaryConditionalOperator(const BinaryConditionalOperator *E) { | |||
6538 | // Evaluate and cache the common expression. We treat it as a temporary, | |||
6539 | // even though it's not quite the same thing. | |||
6540 | LValue CommonLV; | |||
6541 | if (!Evaluate(Info.CurrentCall->createTemporary( | |||
6542 | E->getOpaqueValue(), | |||
6543 | getStorageType(Info.Ctx, E->getOpaqueValue()), false, | |||
6544 | CommonLV), | |||
6545 | Info, E->getCommon())) | |||
6546 | return false; | |||
6547 | ||||
6548 | return HandleConditionalOperator(E); | |||
6549 | } | |||
6550 | ||||
6551 | bool VisitConditionalOperator(const ConditionalOperator *E) { | |||
6552 | bool IsBcpCall = false; | |||
6553 | // If the condition (ignoring parens) is a __builtin_constant_p call, | |||
6554 | // the result is a constant expression if it can be folded without | |||
6555 | // side-effects. This is an important GNU extension. See GCC PR38377 | |||
6556 | // for discussion. | |||
6557 | if (const CallExpr *CallCE = | |||
6558 | dyn_cast<CallExpr>(E->getCond()->IgnoreParenCasts())) | |||
6559 | if (CallCE->getBuiltinCallee() == Builtin::BI__builtin_constant_p) | |||
6560 | IsBcpCall = true; | |||
6561 | ||||
6562 | // Always assume __builtin_constant_p(...) ? ... : ... is a potential | |||
6563 | // constant expression; we can't check whether it's potentially foldable. | |||
6564 | // FIXME: We should instead treat __builtin_constant_p as non-constant if | |||
6565 | // it would return 'false' in this mode. | |||
6566 | if (Info.checkingPotentialConstantExpression() && IsBcpCall) | |||
6567 | return false; | |||
6568 | ||||
6569 | FoldConstant Fold(Info, IsBcpCall); | |||
6570 | if (!HandleConditionalOperator(E)) { | |||
6571 | Fold.keepDiagnostics(); | |||
6572 | return false; | |||
6573 | } | |||
6574 | ||||
6575 | return true; | |||
6576 | } | |||
6577 | ||||
6578 | bool VisitOpaqueValueExpr(const OpaqueValueExpr *E) { | |||
6579 | if (APValue *Value = Info.CurrentCall->getCurrentTemporary(E)) | |||
6580 | return DerivedSuccess(*Value, E); | |||
6581 | ||||
6582 | const Expr *Source = E->getSourceExpr(); | |||
6583 | if (!Source) | |||
6584 | return Error(E); | |||
6585 | if (Source == E) { // sanity checking. | |||
6586 | assert(0 && "OpaqueValueExpr recursively refers to itself")((0 && "OpaqueValueExpr recursively refers to itself" ) ? static_cast<void> (0) : __assert_fail ("0 && \"OpaqueValueExpr recursively refers to itself\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6586, __PRETTY_FUNCTION__)); | |||
6587 | return Error(E); | |||
6588 | } | |||
6589 | return StmtVisitorTy::Visit(Source); | |||
6590 | } | |||
6591 | ||||
6592 | bool VisitCallExpr(const CallExpr *E) { | |||
6593 | APValue Result; | |||
6594 | if (!handleCallExpr(E, Result, nullptr)) | |||
6595 | return false; | |||
6596 | return DerivedSuccess(Result, E); | |||
6597 | } | |||
6598 | ||||
6599 | bool handleCallExpr(const CallExpr *E, APValue &Result, | |||
6600 | const LValue *ResultSlot) { | |||
6601 | const Expr *Callee = E->getCallee()->IgnoreParens(); | |||
6602 | QualType CalleeType = Callee->getType(); | |||
6603 | ||||
6604 | const FunctionDecl *FD = nullptr; | |||
6605 | LValue *This = nullptr, ThisVal; | |||
6606 | auto Args = llvm::makeArrayRef(E->getArgs(), E->getNumArgs()); | |||
6607 | bool HasQualifier = false; | |||
6608 | ||||
6609 | // Extract function decl and 'this' pointer from the callee. | |||
6610 | if (CalleeType->isSpecificBuiltinType(BuiltinType::BoundMember)) { | |||
6611 | const CXXMethodDecl *Member = nullptr; | |||
6612 | if (const MemberExpr *ME = dyn_cast<MemberExpr>(Callee)) { | |||
6613 | // Explicit bound member calls, such as x.f() or p->g(); | |||
6614 | if (!EvaluateObjectArgument(Info, ME->getBase(), ThisVal)) | |||
6615 | return false; | |||
6616 | Member = dyn_cast<CXXMethodDecl>(ME->getMemberDecl()); | |||
6617 | if (!Member) | |||
6618 | return Error(Callee); | |||
6619 | This = &ThisVal; | |||
6620 | HasQualifier = ME->hasQualifier(); | |||
6621 | } else if (const BinaryOperator *BE = dyn_cast<BinaryOperator>(Callee)) { | |||
6622 | // Indirect bound member calls ('.*' or '->*'). | |||
6623 | Member = dyn_cast_or_null<CXXMethodDecl>( | |||
6624 | HandleMemberPointerAccess(Info, BE, ThisVal, false)); | |||
6625 | if (!Member) | |||
6626 | return Error(Callee); | |||
6627 | This = &ThisVal; | |||
6628 | } else if (const auto *PDE = dyn_cast<CXXPseudoDestructorExpr>(Callee)) { | |||
6629 | if (!Info.getLangOpts().CPlusPlus2a) | |||
6630 | Info.CCEDiag(PDE, diag::note_constexpr_pseudo_destructor); | |||
6631 | // FIXME: If pseudo-destructor calls ever start ending the lifetime of | |||
6632 | // their callee, we should start calling HandleDestruction here. | |||
6633 | // For now, we just evaluate the object argument and discard it. | |||
6634 | return EvaluateObjectArgument(Info, PDE->getBase(), ThisVal); | |||
6635 | } else | |||
6636 | return Error(Callee); | |||
6637 | FD = Member; | |||
6638 | } else if (CalleeType->isFunctionPointerType()) { | |||
6639 | LValue Call; | |||
6640 | if (!EvaluatePointer(Callee, Call, Info)) | |||
6641 | return false; | |||
6642 | ||||
6643 | if (!Call.getLValueOffset().isZero()) | |||
6644 | return Error(Callee); | |||
6645 | FD = dyn_cast_or_null<FunctionDecl>( | |||
6646 | Call.getLValueBase().dyn_cast<const ValueDecl*>()); | |||
6647 | if (!FD) | |||
6648 | return Error(Callee); | |||
6649 | // Don't call function pointers which have been cast to some other type. | |||
6650 | // Per DR (no number yet), the caller and callee can differ in noexcept. | |||
6651 | if (!Info.Ctx.hasSameFunctionTypeIgnoringExceptionSpec( | |||
6652 | CalleeType->getPointeeType(), FD->getType())) { | |||
6653 | return Error(E); | |||
6654 | } | |||
6655 | ||||
6656 | // Overloaded operator calls to member functions are represented as normal | |||
6657 | // calls with '*this' as the first argument. | |||
6658 | const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD); | |||
6659 | if (MD && !MD->isStatic()) { | |||
6660 | // FIXME: When selecting an implicit conversion for an overloaded | |||
6661 | // operator delete, we sometimes try to evaluate calls to conversion | |||
6662 | // operators without a 'this' parameter! | |||
6663 | if (Args.empty()) | |||
6664 | return Error(E); | |||
6665 | ||||
6666 | if (!EvaluateObjectArgument(Info, Args[0], ThisVal)) | |||
6667 | return false; | |||
6668 | This = &ThisVal; | |||
6669 | Args = Args.slice(1); | |||
6670 | } else if (MD && MD->isLambdaStaticInvoker()) { | |||
6671 | // Map the static invoker for the lambda back to the call operator. | |||
6672 | // Conveniently, we don't have to slice out the 'this' argument (as is | |||
6673 | // being done for the non-static case), since a static member function | |||
6674 | // doesn't have an implicit argument passed in. | |||
6675 | const CXXRecordDecl *ClosureClass = MD->getParent(); | |||
6676 | assert(((ClosureClass->captures_begin() == ClosureClass->captures_end () && "Number of captures must be zero for conversion to function-ptr" ) ? static_cast<void> (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6678, __PRETTY_FUNCTION__)) | |||
6677 | ClosureClass->captures_begin() == ClosureClass->captures_end() &&((ClosureClass->captures_begin() == ClosureClass->captures_end () && "Number of captures must be zero for conversion to function-ptr" ) ? static_cast<void> (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6678, __PRETTY_FUNCTION__)) | |||
6678 | "Number of captures must be zero for conversion to function-ptr")((ClosureClass->captures_begin() == ClosureClass->captures_end () && "Number of captures must be zero for conversion to function-ptr" ) ? static_cast<void> (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6678, __PRETTY_FUNCTION__)); | |||
6679 | ||||
6680 | const CXXMethodDecl *LambdaCallOp = | |||
6681 | ClosureClass->getLambdaCallOperator(); | |||
6682 | ||||
6683 | // Set 'FD', the function that will be called below, to the call | |||
6684 | // operator. If the closure object represents a generic lambda, find | |||
6685 | // the corresponding specialization of the call operator. | |||
6686 | ||||
6687 | if (ClosureClass->isGenericLambda()) { | |||
6688 | assert(MD->isFunctionTemplateSpecialization() &&((MD->isFunctionTemplateSpecialization() && "A generic lambda's static-invoker function must be a " "template specialization") ? static_cast<void> (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6690, __PRETTY_FUNCTION__)) | |||
6689 | "A generic lambda's static-invoker function must be a "((MD->isFunctionTemplateSpecialization() && "A generic lambda's static-invoker function must be a " "template specialization") ? static_cast<void> (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6690, __PRETTY_FUNCTION__)) | |||
6690 | "template specialization")((MD->isFunctionTemplateSpecialization() && "A generic lambda's static-invoker function must be a " "template specialization") ? static_cast<void> (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6690, __PRETTY_FUNCTION__)); | |||
6691 | const TemplateArgumentList *TAL = MD->getTemplateSpecializationArgs(); | |||
6692 | FunctionTemplateDecl *CallOpTemplate = | |||
6693 | LambdaCallOp->getDescribedFunctionTemplate(); | |||
6694 | void *InsertPos = nullptr; | |||
6695 | FunctionDecl *CorrespondingCallOpSpecialization = | |||
6696 | CallOpTemplate->findSpecialization(TAL->asArray(), InsertPos); | |||
6697 | assert(CorrespondingCallOpSpecialization &&((CorrespondingCallOpSpecialization && "We must always have a function call operator specialization " "that corresponds to our static invoker specialization") ? static_cast <void> (0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6699, __PRETTY_FUNCTION__)) | |||
6698 | "We must always have a function call operator specialization "((CorrespondingCallOpSpecialization && "We must always have a function call operator specialization " "that corresponds to our static invoker specialization") ? static_cast <void> (0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6699, __PRETTY_FUNCTION__)) | |||
6699 | "that corresponds to our static invoker specialization")((CorrespondingCallOpSpecialization && "We must always have a function call operator specialization " "that corresponds to our static invoker specialization") ? static_cast <void> (0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6699, __PRETTY_FUNCTION__)); | |||
6700 | FD = cast<CXXMethodDecl>(CorrespondingCallOpSpecialization); | |||
6701 | } else | |||
6702 | FD = LambdaCallOp; | |||
6703 | } | |||
6704 | } else | |||
6705 | return Error(E); | |||
6706 | ||||
6707 | SmallVector<QualType, 4> CovariantAdjustmentPath; | |||
6708 | if (This) { | |||
6709 | auto *NamedMember = dyn_cast<CXXMethodDecl>(FD); | |||
6710 | if (NamedMember && NamedMember->isVirtual() && !HasQualifier) { | |||
6711 | // Perform virtual dispatch, if necessary. | |||
6712 | FD = HandleVirtualDispatch(Info, E, *This, NamedMember, | |||
6713 | CovariantAdjustmentPath); | |||
6714 | if (!FD) | |||
6715 | return false; | |||
6716 | } else { | |||
6717 | // Check that the 'this' pointer points to an object of the right type. | |||
6718 | // FIXME: If this is an assignment operator call, we may need to change | |||
6719 | // the active union member before we check this. | |||
6720 | if (!checkNonVirtualMemberCallThisPointer(Info, E, *This, NamedMember)) | |||
6721 | return false; | |||
6722 | } | |||
6723 | } | |||
6724 | ||||
6725 | // Destructor calls are different enough that they have their own codepath. | |||
6726 | if (auto *DD = dyn_cast<CXXDestructorDecl>(FD)) { | |||
6727 | assert(This && "no 'this' pointer for destructor call")((This && "no 'this' pointer for destructor call") ? static_cast <void> (0) : __assert_fail ("This && \"no 'this' pointer for destructor call\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6727, __PRETTY_FUNCTION__)); | |||
6728 | return HandleDestruction(Info, E, *This, | |||
6729 | Info.Ctx.getRecordType(DD->getParent())); | |||
6730 | } | |||
6731 | ||||
6732 | const FunctionDecl *Definition = nullptr; | |||
6733 | Stmt *Body = FD->getBody(Definition); | |||
6734 | ||||
6735 | if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body) || | |||
6736 | !HandleFunctionCall(E->getExprLoc(), Definition, This, Args, Body, Info, | |||
6737 | Result, ResultSlot)) | |||
6738 | return false; | |||
6739 | ||||
6740 | if (!CovariantAdjustmentPath.empty() && | |||
6741 | !HandleCovariantReturnAdjustment(Info, E, Result, | |||
6742 | CovariantAdjustmentPath)) | |||
6743 | return false; | |||
6744 | ||||
6745 | return true; | |||
6746 | } | |||
6747 | ||||
6748 | bool VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) { | |||
6749 | return StmtVisitorTy::Visit(E->getInitializer()); | |||
6750 | } | |||
6751 | bool VisitInitListExpr(const InitListExpr *E) { | |||
6752 | if (E->getNumInits() == 0) | |||
6753 | return DerivedZeroInitialization(E); | |||
6754 | if (E->getNumInits() == 1) | |||
6755 | return StmtVisitorTy::Visit(E->getInit(0)); | |||
6756 | return Error(E); | |||
6757 | } | |||
6758 | bool VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { | |||
6759 | return DerivedZeroInitialization(E); | |||
6760 | } | |||
6761 | bool VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) { | |||
6762 | return DerivedZeroInitialization(E); | |||
6763 | } | |||
6764 | bool VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) { | |||
6765 | return DerivedZeroInitialization(E); | |||
6766 | } | |||
6767 | ||||
6768 | /// A member expression where the object is a prvalue is itself a prvalue. | |||
6769 | bool VisitMemberExpr(const MemberExpr *E) { | |||
6770 | assert(!Info.Ctx.getLangOpts().CPlusPlus11 &&((!Info.Ctx.getLangOpts().CPlusPlus11 && "missing temporary materialization conversion" ) ? static_cast<void> (0) : __assert_fail ("!Info.Ctx.getLangOpts().CPlusPlus11 && \"missing temporary materialization conversion\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6771, __PRETTY_FUNCTION__)) | |||
6771 | "missing temporary materialization conversion")((!Info.Ctx.getLangOpts().CPlusPlus11 && "missing temporary materialization conversion" ) ? static_cast<void> (0) : __assert_fail ("!Info.Ctx.getLangOpts().CPlusPlus11 && \"missing temporary materialization conversion\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6771, __PRETTY_FUNCTION__)); | |||
6772 | assert(!E->isArrow() && "missing call to bound member function?")((!E->isArrow() && "missing call to bound member function?" ) ? static_cast<void> (0) : __assert_fail ("!E->isArrow() && \"missing call to bound member function?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6772, __PRETTY_FUNCTION__)); | |||
6773 | ||||
6774 | APValue Val; | |||
6775 | if (!Evaluate(Val, Info, E->getBase())) | |||
6776 | return false; | |||
6777 | ||||
6778 | QualType BaseTy = E->getBase()->getType(); | |||
6779 | ||||
6780 | const FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl()); | |||
6781 | if (!FD) return Error(E); | |||
6782 | assert(!FD->getType()->isReferenceType() && "prvalue reference?")((!FD->getType()->isReferenceType() && "prvalue reference?" ) ? static_cast<void> (0) : __assert_fail ("!FD->getType()->isReferenceType() && \"prvalue reference?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6782, __PRETTY_FUNCTION__)); | |||
6783 | assert(BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() ==((BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl () == FD->getParent()->getCanonicalDecl() && "record / field mismatch" ) ? static_cast<void> (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6784, __PRETTY_FUNCTION__)) | |||
6784 | FD->getParent()->getCanonicalDecl() && "record / field mismatch")((BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl () == FD->getParent()->getCanonicalDecl() && "record / field mismatch" ) ? static_cast<void> (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6784, __PRETTY_FUNCTION__)); | |||
6785 | ||||
6786 | // Note: there is no lvalue base here. But this case should only ever | |||
6787 | // happen in C or in C++98, where we cannot be evaluating a constexpr | |||
6788 | // constructor, which is the only case the base matters. | |||
6789 | CompleteObject Obj(APValue::LValueBase(), &Val, BaseTy); | |||
6790 | SubobjectDesignator Designator(BaseTy); | |||
6791 | Designator.addDeclUnchecked(FD); | |||
6792 | ||||
6793 | APValue Result; | |||
6794 | return extractSubobject(Info, E, Obj, Designator, Result) && | |||
6795 | DerivedSuccess(Result, E); | |||
6796 | } | |||
6797 | ||||
6798 | bool VisitCastExpr(const CastExpr *E) { | |||
6799 | switch (E->getCastKind()) { | |||
6800 | default: | |||
6801 | break; | |||
6802 | ||||
6803 | case CK_AtomicToNonAtomic: { | |||
6804 | APValue AtomicVal; | |||
6805 | // This does not need to be done in place even for class/array types: | |||
6806 | // atomic-to-non-atomic conversion implies copying the object | |||
6807 | // representation. | |||
6808 | if (!Evaluate(AtomicVal, Info, E->getSubExpr())) | |||
6809 | return false; | |||
6810 | return DerivedSuccess(AtomicVal, E); | |||
6811 | } | |||
6812 | ||||
6813 | case CK_NoOp: | |||
6814 | case CK_UserDefinedConversion: | |||
6815 | return StmtVisitorTy::Visit(E->getSubExpr()); | |||
6816 | ||||
6817 | case CK_LValueToRValue: { | |||
6818 | LValue LVal; | |||
6819 | if (!EvaluateLValue(E->getSubExpr(), LVal, Info)) | |||
6820 | return false; | |||
6821 | APValue RVal; | |||
6822 | // Note, we use the subexpression's type in order to retain cv-qualifiers. | |||
6823 | if (!handleLValueToRValueConversion(Info, E, E->getSubExpr()->getType(), | |||
6824 | LVal, RVal)) | |||
6825 | return false; | |||
6826 | return DerivedSuccess(RVal, E); | |||
6827 | } | |||
6828 | case CK_LValueToRValueBitCast: { | |||
6829 | APValue DestValue, SourceValue; | |||
6830 | if (!Evaluate(SourceValue, Info, E->getSubExpr())) | |||
6831 | return false; | |||
6832 | if (!handleLValueToRValueBitCast(Info, DestValue, SourceValue, E)) | |||
6833 | return false; | |||
6834 | return DerivedSuccess(DestValue, E); | |||
6835 | } | |||
6836 | } | |||
6837 | ||||
6838 | return Error(E); | |||
6839 | } | |||
6840 | ||||
6841 | bool VisitUnaryPostInc(const UnaryOperator *UO) { | |||
6842 | return VisitUnaryPostIncDec(UO); | |||
6843 | } | |||
6844 | bool VisitUnaryPostDec(const UnaryOperator *UO) { | |||
6845 | return VisitUnaryPostIncDec(UO); | |||
6846 | } | |||
6847 | bool VisitUnaryPostIncDec(const UnaryOperator *UO) { | |||
6848 | if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure()) | |||
6849 | return Error(UO); | |||
6850 | ||||
6851 | LValue LVal; | |||
6852 | if (!EvaluateLValue(UO->getSubExpr(), LVal, Info)) | |||
6853 | return false; | |||
6854 | APValue RVal; | |||
6855 | if (!handleIncDec(this->Info, UO, LVal, UO->getSubExpr()->getType(), | |||
6856 | UO->isIncrementOp(), &RVal)) | |||
6857 | return false; | |||
6858 | return DerivedSuccess(RVal, UO); | |||
6859 | } | |||
6860 | ||||
6861 | bool VisitStmtExpr(const StmtExpr *E) { | |||
6862 | // We will have checked the full-expressions inside the statement expression | |||
6863 | // when they were completed, and don't need to check them again now. | |||
6864 | if (Info.checkingForUndefinedBehavior()) | |||
6865 | return Error(E); | |||
6866 | ||||
6867 | const CompoundStmt *CS = E->getSubStmt(); | |||
6868 | if (CS->body_empty()) | |||
6869 | return true; | |||
6870 | ||||
6871 | BlockScopeRAII Scope(Info); | |||
6872 | for (CompoundStmt::const_body_iterator BI = CS->body_begin(), | |||
6873 | BE = CS->body_end(); | |||
6874 | /**/; ++BI) { | |||
6875 | if (BI + 1 == BE) { | |||
6876 | const Expr *FinalExpr = dyn_cast<Expr>(*BI); | |||
6877 | if (!FinalExpr) { | |||
6878 | Info.FFDiag((*BI)->getBeginLoc(), | |||
6879 | diag::note_constexpr_stmt_expr_unsupported); | |||
6880 | return false; | |||
6881 | } | |||
6882 | return this->Visit(FinalExpr) && Scope.destroy(); | |||
6883 | } | |||
6884 | ||||
6885 | APValue ReturnValue; | |||
6886 | StmtResult Result = { ReturnValue, nullptr }; | |||
6887 | EvalStmtResult ESR = EvaluateStmt(Result, Info, *BI); | |||
6888 | if (ESR != ESR_Succeeded) { | |||
6889 | // FIXME: If the statement-expression terminated due to 'return', | |||
6890 | // 'break', or 'continue', it would be nice to propagate that to | |||
6891 | // the outer statement evaluation rather than bailing out. | |||
6892 | if (ESR != ESR_Failed) | |||
6893 | Info.FFDiag((*BI)->getBeginLoc(), | |||
6894 | diag::note_constexpr_stmt_expr_unsupported); | |||
6895 | return false; | |||
6896 | } | |||
6897 | } | |||
6898 | ||||
6899 | llvm_unreachable("Return from function from the loop above.")::llvm::llvm_unreachable_internal("Return from function from the loop above." , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6899); | |||
6900 | } | |||
6901 | ||||
6902 | /// Visit a value which is evaluated, but whose value is ignored. | |||
6903 | void VisitIgnoredValue(const Expr *E) { | |||
6904 | EvaluateIgnoredValue(Info, E); | |||
6905 | } | |||
6906 | ||||
6907 | /// Potentially visit a MemberExpr's base expression. | |||
6908 | void VisitIgnoredBaseExpression(const Expr *E) { | |||
6909 | // While MSVC doesn't evaluate the base expression, it does diagnose the | |||
6910 | // presence of side-effecting behavior. | |||
6911 | if (Info.getLangOpts().MSVCCompat && !E->HasSideEffects(Info.Ctx)) | |||
6912 | return; | |||
6913 | VisitIgnoredValue(E); | |||
6914 | } | |||
6915 | }; | |||
6916 | ||||
6917 | } // namespace | |||
6918 | ||||
6919 | //===----------------------------------------------------------------------===// | |||
6920 | // Common base class for lvalue and temporary evaluation. | |||
6921 | //===----------------------------------------------------------------------===// | |||
6922 | namespace { | |||
6923 | template<class Derived> | |||
6924 | class LValueExprEvaluatorBase | |||
6925 | : public ExprEvaluatorBase<Derived> { | |||
6926 | protected: | |||
6927 | LValue &Result; | |||
6928 | bool InvalidBaseOK; | |||
6929 | typedef LValueExprEvaluatorBase LValueExprEvaluatorBaseTy; | |||
6930 | typedef ExprEvaluatorBase<Derived> ExprEvaluatorBaseTy; | |||
6931 | ||||
6932 | bool Success(APValue::LValueBase B) { | |||
6933 | Result.set(B); | |||
6934 | return true; | |||
6935 | } | |||
6936 | ||||
6937 | bool evaluatePointer(const Expr *E, LValue &Result) { | |||
6938 | return EvaluatePointer(E, Result, this->Info, InvalidBaseOK); | |||
6939 | } | |||
6940 | ||||
6941 | public: | |||
6942 | LValueExprEvaluatorBase(EvalInfo &Info, LValue &Result, bool InvalidBaseOK) | |||
6943 | : ExprEvaluatorBaseTy(Info), Result(Result), | |||
6944 | InvalidBaseOK(InvalidBaseOK) {} | |||
6945 | ||||
6946 | bool Success(const APValue &V, const Expr *E) { | |||
6947 | Result.setFrom(this->Info.Ctx, V); | |||
6948 | return true; | |||
6949 | } | |||
6950 | ||||
6951 | bool VisitMemberExpr(const MemberExpr *E) { | |||
6952 | // Handle non-static data members. | |||
6953 | QualType BaseTy; | |||
6954 | bool EvalOK; | |||
6955 | if (E->isArrow()) { | |||
6956 | EvalOK = evaluatePointer(E->getBase(), Result); | |||
6957 | BaseTy = E->getBase()->getType()->castAs<PointerType>()->getPointeeType(); | |||
6958 | } else if (E->getBase()->isRValue()) { | |||
6959 | assert(E->getBase()->getType()->isRecordType())((E->getBase()->getType()->isRecordType()) ? static_cast <void> (0) : __assert_fail ("E->getBase()->getType()->isRecordType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6959, __PRETTY_FUNCTION__)); | |||
6960 | EvalOK = EvaluateTemporary(E->getBase(), Result, this->Info); | |||
6961 | BaseTy = E->getBase()->getType(); | |||
6962 | } else { | |||
6963 | EvalOK = this->Visit(E->getBase()); | |||
6964 | BaseTy = E->getBase()->getType(); | |||
6965 | } | |||
6966 | if (!EvalOK) { | |||
6967 | if (!InvalidBaseOK) | |||
6968 | return false; | |||
6969 | Result.setInvalid(E); | |||
6970 | return true; | |||
6971 | } | |||
6972 | ||||
6973 | const ValueDecl *MD = E->getMemberDecl(); | |||
6974 | if (const FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl())) { | |||
6975 | assert(BaseTy->getAs<RecordType>()->getDecl()->getCanonicalDecl() ==((BaseTy->getAs<RecordType>()->getDecl()->getCanonicalDecl () == FD->getParent()->getCanonicalDecl() && "record / field mismatch" ) ? static_cast<void> (0) : __assert_fail ("BaseTy->getAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6976, __PRETTY_FUNCTION__)) | |||
6976 | FD->getParent()->getCanonicalDecl() && "record / field mismatch")((BaseTy->getAs<RecordType>()->getDecl()->getCanonicalDecl () == FD->getParent()->getCanonicalDecl() && "record / field mismatch" ) ? static_cast<void> (0) : __assert_fail ("BaseTy->getAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 6976, __PRETTY_FUNCTION__)); | |||
6977 | (void)BaseTy; | |||
6978 | if (!HandleLValueMember(this->Info, E, Result, FD)) | |||
6979 | return false; | |||
6980 | } else if (const IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(MD)) { | |||
6981 | if (!HandleLValueIndirectMember(this->Info, E, Result, IFD)) | |||
6982 | return false; | |||
6983 | } else | |||
6984 | return this->Error(E); | |||
6985 | ||||
6986 | if (MD->getType()->isReferenceType()) { | |||
6987 | APValue RefValue; | |||
6988 | if (!handleLValueToRValueConversion(this->Info, E, MD->getType(), Result, | |||
6989 | RefValue)) | |||
6990 | return false; | |||
6991 | return Success(RefValue, E); | |||
6992 | } | |||
6993 | return true; | |||
6994 | } | |||
6995 | ||||
6996 | bool VisitBinaryOperator(const BinaryOperator *E) { | |||
6997 | switch (E->getOpcode()) { | |||
6998 | default: | |||
6999 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
7000 | ||||
7001 | case BO_PtrMemD: | |||
7002 | case BO_PtrMemI: | |||
7003 | return HandleMemberPointerAccess(this->Info, E, Result); | |||
7004 | } | |||
7005 | } | |||
7006 | ||||
7007 | bool VisitCastExpr(const CastExpr *E) { | |||
7008 | switch (E->getCastKind()) { | |||
7009 | default: | |||
7010 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
7011 | ||||
7012 | case CK_DerivedToBase: | |||
7013 | case CK_UncheckedDerivedToBase: | |||
7014 | if (!this->Visit(E->getSubExpr())) | |||
7015 | return false; | |||
7016 | ||||
7017 | // Now figure out the necessary offset to add to the base LV to get from | |||
7018 | // the derived class to the base class. | |||
7019 | return HandleLValueBasePath(this->Info, E, E->getSubExpr()->getType(), | |||
7020 | Result); | |||
7021 | } | |||
7022 | } | |||
7023 | }; | |||
7024 | } | |||
7025 | ||||
7026 | //===----------------------------------------------------------------------===// | |||
7027 | // LValue Evaluation | |||
7028 | // | |||
7029 | // This is used for evaluating lvalues (in C and C++), xvalues (in C++11), | |||
7030 | // function designators (in C), decl references to void objects (in C), and | |||
7031 | // temporaries (if building with -Wno-address-of-temporary). | |||
7032 | // | |||
7033 | // LValue evaluation produces values comprising a base expression of one of the | |||
7034 | // following types: | |||
7035 | // - Declarations | |||
7036 | // * VarDecl | |||
7037 | // * FunctionDecl | |||
7038 | // - Literals | |||
7039 | // * CompoundLiteralExpr in C (and in global scope in C++) | |||
7040 | // * StringLiteral | |||
7041 | // * PredefinedExpr | |||
7042 | // * ObjCStringLiteralExpr | |||
7043 | // * ObjCEncodeExpr | |||
7044 | // * AddrLabelExpr | |||
7045 | // * BlockExpr | |||
7046 | // * CallExpr for a MakeStringConstant builtin | |||
7047 | // - typeid(T) expressions, as TypeInfoLValues | |||
7048 | // - Locals and temporaries | |||
7049 | // * MaterializeTemporaryExpr | |||
7050 | // * Any Expr, with a CallIndex indicating the function in which the temporary | |||
7051 | // was evaluated, for cases where the MaterializeTemporaryExpr is missing | |||
7052 | // from the AST (FIXME). | |||
7053 | // * A MaterializeTemporaryExpr that has static storage duration, with no | |||
7054 | // CallIndex, for a lifetime-extended temporary. | |||
7055 | // plus an offset in bytes. | |||
7056 | //===----------------------------------------------------------------------===// | |||
7057 | namespace { | |||
7058 | class LValueExprEvaluator | |||
7059 | : public LValueExprEvaluatorBase<LValueExprEvaluator> { | |||
7060 | public: | |||
7061 | LValueExprEvaluator(EvalInfo &Info, LValue &Result, bool InvalidBaseOK) : | |||
7062 | LValueExprEvaluatorBaseTy(Info, Result, InvalidBaseOK) {} | |||
7063 | ||||
7064 | bool VisitVarDecl(const Expr *E, const VarDecl *VD); | |||
7065 | bool VisitUnaryPreIncDec(const UnaryOperator *UO); | |||
7066 | ||||
7067 | bool VisitDeclRefExpr(const DeclRefExpr *E); | |||
7068 | bool VisitPredefinedExpr(const PredefinedExpr *E) { return Success(E); } | |||
7069 | bool VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E); | |||
7070 | bool VisitCompoundLiteralExpr(const CompoundLiteralExpr *E); | |||
7071 | bool VisitMemberExpr(const MemberExpr *E); | |||
7072 | bool VisitStringLiteral(const StringLiteral *E) { return Success(E); } | |||
7073 | bool VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { return Success(E); } | |||
7074 | bool VisitCXXTypeidExpr(const CXXTypeidExpr *E); | |||
7075 | bool VisitCXXUuidofExpr(const CXXUuidofExpr *E); | |||
7076 | bool VisitArraySubscriptExpr(const ArraySubscriptExpr *E); | |||
7077 | bool VisitUnaryDeref(const UnaryOperator *E); | |||
7078 | bool VisitUnaryReal(const UnaryOperator *E); | |||
7079 | bool VisitUnaryImag(const UnaryOperator *E); | |||
7080 | bool VisitUnaryPreInc(const UnaryOperator *UO) { | |||
7081 | return VisitUnaryPreIncDec(UO); | |||
7082 | } | |||
7083 | bool VisitUnaryPreDec(const UnaryOperator *UO) { | |||
7084 | return VisitUnaryPreIncDec(UO); | |||
7085 | } | |||
7086 | bool VisitBinAssign(const BinaryOperator *BO); | |||
7087 | bool VisitCompoundAssignOperator(const CompoundAssignOperator *CAO); | |||
7088 | ||||
7089 | bool VisitCastExpr(const CastExpr *E) { | |||
7090 | switch (E->getCastKind()) { | |||
7091 | default: | |||
7092 | return LValueExprEvaluatorBaseTy::VisitCastExpr(E); | |||
7093 | ||||
7094 | case CK_LValueBitCast: | |||
7095 | this->CCEDiag(E, diag::note_constexpr_invalid_cast) << 2; | |||
7096 | if (!Visit(E->getSubExpr())) | |||
7097 | return false; | |||
7098 | Result.Designator.setInvalid(); | |||
7099 | return true; | |||
7100 | ||||
7101 | case CK_BaseToDerived: | |||
7102 | if (!Visit(E->getSubExpr())) | |||
7103 | return false; | |||
7104 | return HandleBaseToDerivedCast(Info, E, Result); | |||
7105 | ||||
7106 | case CK_Dynamic: | |||
7107 | if (!Visit(E->getSubExpr())) | |||
7108 | return false; | |||
7109 | return HandleDynamicCast(Info, cast<ExplicitCastExpr>(E), Result); | |||
7110 | } | |||
7111 | } | |||
7112 | }; | |||
7113 | } // end anonymous namespace | |||
7114 | ||||
7115 | /// Evaluate an expression as an lvalue. This can be legitimately called on | |||
7116 | /// expressions which are not glvalues, in three cases: | |||
7117 | /// * function designators in C, and | |||
7118 | /// * "extern void" objects | |||
7119 | /// * @selector() expressions in Objective-C | |||
7120 | static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info, | |||
7121 | bool InvalidBaseOK) { | |||
7122 | assert(E->isGLValue() || E->getType()->isFunctionType() ||((E->isGLValue() || E->getType()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr> (E)) ? static_cast<void> (0) : __assert_fail ("E->isGLValue() || E->getType()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E)" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7123, __PRETTY_FUNCTION__)) | |||
7123 | E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E))((E->isGLValue() || E->getType()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr> (E)) ? static_cast<void> (0) : __assert_fail ("E->isGLValue() || E->getType()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E)" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7123, __PRETTY_FUNCTION__)); | |||
7124 | return LValueExprEvaluator(Info, Result, InvalidBaseOK).Visit(E); | |||
7125 | } | |||
7126 | ||||
7127 | bool LValueExprEvaluator::VisitDeclRefExpr(const DeclRefExpr *E) { | |||
7128 | if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(E->getDecl())) | |||
7129 | return Success(FD); | |||
7130 | if (const VarDecl *VD = dyn_cast<VarDecl>(E->getDecl())) | |||
7131 | return VisitVarDecl(E, VD); | |||
7132 | if (const BindingDecl *BD = dyn_cast<BindingDecl>(E->getDecl())) | |||
7133 | return Visit(BD->getBinding()); | |||
7134 | return Error(E); | |||
7135 | } | |||
7136 | ||||
7137 | ||||
7138 | bool LValueExprEvaluator::VisitVarDecl(const Expr *E, const VarDecl *VD) { | |||
7139 | ||||
7140 | // If we are within a lambda's call operator, check whether the 'VD' referred | |||
7141 | // to within 'E' actually represents a lambda-capture that maps to a | |||
7142 | // data-member/field within the closure object, and if so, evaluate to the | |||
7143 | // field or what the field refers to. | |||
7144 | if (Info.CurrentCall && isLambdaCallOperator(Info.CurrentCall->Callee) && | |||
7145 | isa<DeclRefExpr>(E) && | |||
7146 | cast<DeclRefExpr>(E)->refersToEnclosingVariableOrCapture()) { | |||
7147 | // We don't always have a complete capture-map when checking or inferring if | |||
7148 | // the function call operator meets the requirements of a constexpr function | |||
7149 | // - but we don't need to evaluate the captures to determine constexprness | |||
7150 | // (dcl.constexpr C++17). | |||
7151 | if (Info.checkingPotentialConstantExpression()) | |||
7152 | return false; | |||
7153 | ||||
7154 | if (auto *FD = Info.CurrentCall->LambdaCaptureFields.lookup(VD)) { | |||
7155 | // Start with 'Result' referring to the complete closure object... | |||
7156 | Result = *Info.CurrentCall->This; | |||
7157 | // ... then update it to refer to the field of the closure object | |||
7158 | // that represents the capture. | |||
7159 | if (!HandleLValueMember(Info, E, Result, FD)) | |||
7160 | return false; | |||
7161 | // And if the field is of reference type, update 'Result' to refer to what | |||
7162 | // the field refers to. | |||
7163 | if (FD->getType()->isReferenceType()) { | |||
7164 | APValue RVal; | |||
7165 | if (!handleLValueToRValueConversion(Info, E, FD->getType(), Result, | |||
7166 | RVal)) | |||
7167 | return false; | |||
7168 | Result.setFrom(Info.Ctx, RVal); | |||
7169 | } | |||
7170 | return true; | |||
7171 | } | |||
7172 | } | |||
7173 | CallStackFrame *Frame = nullptr; | |||
7174 | if (VD->hasLocalStorage() && Info.CurrentCall->Index > 1) { | |||
7175 | // Only if a local variable was declared in the function currently being | |||
7176 | // evaluated, do we expect to be able to find its value in the current | |||
7177 | // frame. (Otherwise it was likely declared in an enclosing context and | |||
7178 | // could either have a valid evaluatable value (for e.g. a constexpr | |||
7179 | // variable) or be ill-formed (and trigger an appropriate evaluation | |||
7180 | // diagnostic)). | |||
7181 | if (Info.CurrentCall->Callee && | |||
7182 | Info.CurrentCall->Callee->Equals(VD->getDeclContext())) { | |||
7183 | Frame = Info.CurrentCall; | |||
7184 | } | |||
7185 | } | |||
7186 | ||||
7187 | if (!VD->getType()->isReferenceType()) { | |||
7188 | if (Frame) { | |||
7189 | Result.set({VD, Frame->Index, | |||
7190 | Info.CurrentCall->getCurrentTemporaryVersion(VD)}); | |||
7191 | return true; | |||
7192 | } | |||
7193 | return Success(VD); | |||
7194 | } | |||
7195 | ||||
7196 | APValue *V; | |||
7197 | if (!evaluateVarDeclInit(Info, E, VD, Frame, V, nullptr)) | |||
7198 | return false; | |||
7199 | if (!V->hasValue()) { | |||
7200 | // FIXME: Is it possible for V to be indeterminate here? If so, we should | |||
7201 | // adjust the diagnostic to say that. | |||
7202 | if (!Info.checkingPotentialConstantExpression()) | |||
7203 | Info.FFDiag(E, diag::note_constexpr_use_uninit_reference); | |||
7204 | return false; | |||
7205 | } | |||
7206 | return Success(*V, E); | |||
7207 | } | |||
7208 | ||||
7209 | bool LValueExprEvaluator::VisitMaterializeTemporaryExpr( | |||
7210 | const MaterializeTemporaryExpr *E) { | |||
7211 | // Walk through the expression to find the materialized temporary itself. | |||
7212 | SmallVector<const Expr *, 2> CommaLHSs; | |||
7213 | SmallVector<SubobjectAdjustment, 2> Adjustments; | |||
7214 | const Expr *Inner = E->GetTemporaryExpr()-> | |||
7215 | skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); | |||
7216 | ||||
7217 | // If we passed any comma operators, evaluate their LHSs. | |||
7218 | for (unsigned I = 0, N = CommaLHSs.size(); I != N; ++I) | |||
7219 | if (!EvaluateIgnoredValue(Info, CommaLHSs[I])) | |||
7220 | return false; | |||
7221 | ||||
7222 | // A materialized temporary with static storage duration can appear within the | |||
7223 | // result of a constant expression evaluation, so we need to preserve its | |||
7224 | // value for use outside this evaluation. | |||
7225 | APValue *Value; | |||
7226 | if (E->getStorageDuration() == SD_Static) { | |||
7227 | Value = Info.Ctx.getMaterializedTemporaryValue(E, true); | |||
7228 | *Value = APValue(); | |||
7229 | Result.set(E); | |||
7230 | } else { | |||
7231 | Value = &Info.CurrentCall->createTemporary( | |||
7232 | E, E->getType(), E->getStorageDuration() == SD_Automatic, Result); | |||
7233 | } | |||
7234 | ||||
7235 | QualType Type = Inner->getType(); | |||
7236 | ||||
7237 | // Materialize the temporary itself. | |||
7238 | if (!EvaluateInPlace(*Value, Info, Result, Inner)) { | |||
7239 | *Value = APValue(); | |||
7240 | return false; | |||
7241 | } | |||
7242 | ||||
7243 | // Adjust our lvalue to refer to the desired subobject. | |||
7244 | for (unsigned I = Adjustments.size(); I != 0; /**/) { | |||
7245 | --I; | |||
7246 | switch (Adjustments[I].Kind) { | |||
7247 | case SubobjectAdjustment::DerivedToBaseAdjustment: | |||
7248 | if (!HandleLValueBasePath(Info, Adjustments[I].DerivedToBase.BasePath, | |||
7249 | Type, Result)) | |||
7250 | return false; | |||
7251 | Type = Adjustments[I].DerivedToBase.BasePath->getType(); | |||
7252 | break; | |||
7253 | ||||
7254 | case SubobjectAdjustment::FieldAdjustment: | |||
7255 | if (!HandleLValueMember(Info, E, Result, Adjustments[I].Field)) | |||
7256 | return false; | |||
7257 | Type = Adjustments[I].Field->getType(); | |||
7258 | break; | |||
7259 | ||||
7260 | case SubobjectAdjustment::MemberPointerAdjustment: | |||
7261 | if (!HandleMemberPointerAccess(this->Info, Type, Result, | |||
7262 | Adjustments[I].Ptr.RHS)) | |||
7263 | return false; | |||
7264 | Type = Adjustments[I].Ptr.MPT->getPointeeType(); | |||
7265 | break; | |||
7266 | } | |||
7267 | } | |||
7268 | ||||
7269 | return true; | |||
7270 | } | |||
7271 | ||||
7272 | bool | |||
7273 | LValueExprEvaluator::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) { | |||
7274 | assert((!Info.getLangOpts().CPlusPlus || E->isFileScope()) &&(((!Info.getLangOpts().CPlusPlus || E->isFileScope()) && "lvalue compound literal in c++?") ? static_cast<void> (0) : __assert_fail ("(!Info.getLangOpts().CPlusPlus || E->isFileScope()) && \"lvalue compound literal in c++?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7275, __PRETTY_FUNCTION__)) | |||
7275 | "lvalue compound literal in c++?")(((!Info.getLangOpts().CPlusPlus || E->isFileScope()) && "lvalue compound literal in c++?") ? static_cast<void> (0) : __assert_fail ("(!Info.getLangOpts().CPlusPlus || E->isFileScope()) && \"lvalue compound literal in c++?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7275, __PRETTY_FUNCTION__)); | |||
7276 | // Defer visiting the literal until the lvalue-to-rvalue conversion. We can | |||
7277 | // only see this when folding in C, so there's no standard to follow here. | |||
7278 | return Success(E); | |||
7279 | } | |||
7280 | ||||
7281 | bool LValueExprEvaluator::VisitCXXTypeidExpr(const CXXTypeidExpr *E) { | |||
7282 | TypeInfoLValue TypeInfo; | |||
7283 | ||||
7284 | if (!E->isPotentiallyEvaluated()) { | |||
7285 | if (E->isTypeOperand()) | |||
7286 | TypeInfo = TypeInfoLValue(E->getTypeOperand(Info.Ctx).getTypePtr()); | |||
7287 | else | |||
7288 | TypeInfo = TypeInfoLValue(E->getExprOperand()->getType().getTypePtr()); | |||
7289 | } else { | |||
7290 | if (!Info.Ctx.getLangOpts().CPlusPlus2a) { | |||
7291 | Info.CCEDiag(E, diag::note_constexpr_typeid_polymorphic) | |||
7292 | << E->getExprOperand()->getType() | |||
7293 | << E->getExprOperand()->getSourceRange(); | |||
7294 | } | |||
7295 | ||||
7296 | if (!Visit(E->getExprOperand())) | |||
7297 | return false; | |||
7298 | ||||
7299 | Optional<DynamicType> DynType = | |||
7300 | ComputeDynamicType(Info, E, Result, AK_TypeId); | |||
7301 | if (!DynType) | |||
7302 | return false; | |||
7303 | ||||
7304 | TypeInfo = | |||
7305 | TypeInfoLValue(Info.Ctx.getRecordType(DynType->Type).getTypePtr()); | |||
7306 | } | |||
7307 | ||||
7308 | return Success(APValue::LValueBase::getTypeInfo(TypeInfo, E->getType())); | |||
7309 | } | |||
7310 | ||||
7311 | bool LValueExprEvaluator::VisitCXXUuidofExpr(const CXXUuidofExpr *E) { | |||
7312 | return Success(E); | |||
7313 | } | |||
7314 | ||||
7315 | bool LValueExprEvaluator::VisitMemberExpr(const MemberExpr *E) { | |||
7316 | // Handle static data members. | |||
7317 | if (const VarDecl *VD = dyn_cast<VarDecl>(E->getMemberDecl())) { | |||
7318 | VisitIgnoredBaseExpression(E->getBase()); | |||
7319 | return VisitVarDecl(E, VD); | |||
7320 | } | |||
7321 | ||||
7322 | // Handle static member functions. | |||
7323 | if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl())) { | |||
7324 | if (MD->isStatic()) { | |||
7325 | VisitIgnoredBaseExpression(E->getBase()); | |||
7326 | return Success(MD); | |||
7327 | } | |||
7328 | } | |||
7329 | ||||
7330 | // Handle non-static data members. | |||
7331 | return LValueExprEvaluatorBaseTy::VisitMemberExpr(E); | |||
7332 | } | |||
7333 | ||||
7334 | bool LValueExprEvaluator::VisitArraySubscriptExpr(const ArraySubscriptExpr *E) { | |||
7335 | // FIXME: Deal with vectors as array subscript bases. | |||
7336 | if (E->getBase()->getType()->isVectorType()) | |||
7337 | return Error(E); | |||
7338 | ||||
7339 | bool Success = true; | |||
7340 | if (!evaluatePointer(E->getBase(), Result)) { | |||
7341 | if (!Info.noteFailure()) | |||
7342 | return false; | |||
7343 | Success = false; | |||
7344 | } | |||
7345 | ||||
7346 | APSInt Index; | |||
7347 | if (!EvaluateInteger(E->getIdx(), Index, Info)) | |||
7348 | return false; | |||
7349 | ||||
7350 | return Success && | |||
7351 | HandleLValueArrayAdjustment(Info, E, Result, E->getType(), Index); | |||
7352 | } | |||
7353 | ||||
7354 | bool LValueExprEvaluator::VisitUnaryDeref(const UnaryOperator *E) { | |||
7355 | return evaluatePointer(E->getSubExpr(), Result); | |||
7356 | } | |||
7357 | ||||
7358 | bool LValueExprEvaluator::VisitUnaryReal(const UnaryOperator *E) { | |||
7359 | if (!Visit(E->getSubExpr())) | |||
7360 | return false; | |||
7361 | // __real is a no-op on scalar lvalues. | |||
7362 | if (E->getSubExpr()->getType()->isAnyComplexType()) | |||
7363 | HandleLValueComplexElement(Info, E, Result, E->getType(), false); | |||
7364 | return true; | |||
7365 | } | |||
7366 | ||||
7367 | bool LValueExprEvaluator::VisitUnaryImag(const UnaryOperator *E) { | |||
7368 | assert(E->getSubExpr()->getType()->isAnyComplexType() &&((E->getSubExpr()->getType()->isAnyComplexType() && "lvalue __imag__ on scalar?") ? static_cast<void> (0) : __assert_fail ("E->getSubExpr()->getType()->isAnyComplexType() && \"lvalue __imag__ on scalar?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7369, __PRETTY_FUNCTION__)) | |||
7369 | "lvalue __imag__ on scalar?")((E->getSubExpr()->getType()->isAnyComplexType() && "lvalue __imag__ on scalar?") ? static_cast<void> (0) : __assert_fail ("E->getSubExpr()->getType()->isAnyComplexType() && \"lvalue __imag__ on scalar?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7369, __PRETTY_FUNCTION__)); | |||
7370 | if (!Visit(E->getSubExpr())) | |||
7371 | return false; | |||
7372 | HandleLValueComplexElement(Info, E, Result, E->getType(), true); | |||
7373 | return true; | |||
7374 | } | |||
7375 | ||||
7376 | bool LValueExprEvaluator::VisitUnaryPreIncDec(const UnaryOperator *UO) { | |||
7377 | if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure()) | |||
7378 | return Error(UO); | |||
7379 | ||||
7380 | if (!this->Visit(UO->getSubExpr())) | |||
7381 | return false; | |||
7382 | ||||
7383 | return handleIncDec( | |||
7384 | this->Info, UO, Result, UO->getSubExpr()->getType(), | |||
7385 | UO->isIncrementOp(), nullptr); | |||
7386 | } | |||
7387 | ||||
7388 | bool LValueExprEvaluator::VisitCompoundAssignOperator( | |||
7389 | const CompoundAssignOperator *CAO) { | |||
7390 | if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure()) | |||
7391 | return Error(CAO); | |||
7392 | ||||
7393 | APValue RHS; | |||
7394 | ||||
7395 | // The overall lvalue result is the result of evaluating the LHS. | |||
7396 | if (!this->Visit(CAO->getLHS())) { | |||
7397 | if (Info.noteFailure()) | |||
7398 | Evaluate(RHS, this->Info, CAO->getRHS()); | |||
7399 | return false; | |||
7400 | } | |||
7401 | ||||
7402 | if (!Evaluate(RHS, this->Info, CAO->getRHS())) | |||
7403 | return false; | |||
7404 | ||||
7405 | return handleCompoundAssignment( | |||
7406 | this->Info, CAO, | |||
7407 | Result, CAO->getLHS()->getType(), CAO->getComputationLHSType(), | |||
7408 | CAO->getOpForCompoundAssignment(CAO->getOpcode()), RHS); | |||
7409 | } | |||
7410 | ||||
7411 | bool LValueExprEvaluator::VisitBinAssign(const BinaryOperator *E) { | |||
7412 | if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure()) | |||
7413 | return Error(E); | |||
7414 | ||||
7415 | APValue NewVal; | |||
7416 | ||||
7417 | if (!this->Visit(E->getLHS())) { | |||
7418 | if (Info.noteFailure()) | |||
7419 | Evaluate(NewVal, this->Info, E->getRHS()); | |||
7420 | return false; | |||
7421 | } | |||
7422 | ||||
7423 | if (!Evaluate(NewVal, this->Info, E->getRHS())) | |||
7424 | return false; | |||
7425 | ||||
7426 | if (Info.getLangOpts().CPlusPlus2a && | |||
7427 | !HandleUnionActiveMemberChange(Info, E->getLHS(), Result)) | |||
7428 | return false; | |||
7429 | ||||
7430 | return handleAssignment(this->Info, E, Result, E->getLHS()->getType(), | |||
7431 | NewVal); | |||
7432 | } | |||
7433 | ||||
7434 | //===----------------------------------------------------------------------===// | |||
7435 | // Pointer Evaluation | |||
7436 | //===----------------------------------------------------------------------===// | |||
7437 | ||||
7438 | /// Attempts to compute the number of bytes available at the pointer | |||
7439 | /// returned by a function with the alloc_size attribute. Returns true if we | |||
7440 | /// were successful. Places an unsigned number into `Result`. | |||
7441 | /// | |||
7442 | /// This expects the given CallExpr to be a call to a function with an | |||
7443 | /// alloc_size attribute. | |||
7444 | static bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx, | |||
7445 | const CallExpr *Call, | |||
7446 | llvm::APInt &Result) { | |||
7447 | const AllocSizeAttr *AllocSize = getAllocSizeAttr(Call); | |||
7448 | ||||
7449 | assert(AllocSize && AllocSize->getElemSizeParam().isValid())((AllocSize && AllocSize->getElemSizeParam().isValid ()) ? static_cast<void> (0) : __assert_fail ("AllocSize && AllocSize->getElemSizeParam().isValid()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7449, __PRETTY_FUNCTION__)); | |||
7450 | unsigned SizeArgNo = AllocSize->getElemSizeParam().getASTIndex(); | |||
7451 | unsigned BitsInSizeT = Ctx.getTypeSize(Ctx.getSizeType()); | |||
7452 | if (Call->getNumArgs() <= SizeArgNo) | |||
7453 | return false; | |||
7454 | ||||
7455 | auto EvaluateAsSizeT = [&](const Expr *E, APSInt &Into) { | |||
7456 | Expr::EvalResult ExprResult; | |||
7457 | if (!E->EvaluateAsInt(ExprResult, Ctx, Expr::SE_AllowSideEffects)) | |||
7458 | return false; | |||
7459 | Into = ExprResult.Val.getInt(); | |||
7460 | if (Into.isNegative() || !Into.isIntN(BitsInSizeT)) | |||
7461 | return false; | |||
7462 | Into = Into.zextOrSelf(BitsInSizeT); | |||
7463 | return true; | |||
7464 | }; | |||
7465 | ||||
7466 | APSInt SizeOfElem; | |||
7467 | if (!EvaluateAsSizeT(Call->getArg(SizeArgNo), SizeOfElem)) | |||
7468 | return false; | |||
7469 | ||||
7470 | if (!AllocSize->getNumElemsParam().isValid()) { | |||
7471 | Result = std::move(SizeOfElem); | |||
7472 | return true; | |||
7473 | } | |||
7474 | ||||
7475 | APSInt NumberOfElems; | |||
7476 | unsigned NumArgNo = AllocSize->getNumElemsParam().getASTIndex(); | |||
7477 | if (!EvaluateAsSizeT(Call->getArg(NumArgNo), NumberOfElems)) | |||
7478 | return false; | |||
7479 | ||||
7480 | bool Overflow; | |||
7481 | llvm::APInt BytesAvailable = SizeOfElem.umul_ov(NumberOfElems, Overflow); | |||
7482 | if (Overflow) | |||
7483 | return false; | |||
7484 | ||||
7485 | Result = std::move(BytesAvailable); | |||
7486 | return true; | |||
7487 | } | |||
7488 | ||||
7489 | /// Convenience function. LVal's base must be a call to an alloc_size | |||
7490 | /// function. | |||
7491 | static bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx, | |||
7492 | const LValue &LVal, | |||
7493 | llvm::APInt &Result) { | |||
7494 | assert(isBaseAnAllocSizeCall(LVal.getLValueBase()) &&((isBaseAnAllocSizeCall(LVal.getLValueBase()) && "Can't get the size of a non alloc_size function" ) ? static_cast<void> (0) : __assert_fail ("isBaseAnAllocSizeCall(LVal.getLValueBase()) && \"Can't get the size of a non alloc_size function\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7495, __PRETTY_FUNCTION__)) | |||
7495 | "Can't get the size of a non alloc_size function")((isBaseAnAllocSizeCall(LVal.getLValueBase()) && "Can't get the size of a non alloc_size function" ) ? static_cast<void> (0) : __assert_fail ("isBaseAnAllocSizeCall(LVal.getLValueBase()) && \"Can't get the size of a non alloc_size function\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7495, __PRETTY_FUNCTION__)); | |||
7496 | const auto *Base = LVal.getLValueBase().get<const Expr *>(); | |||
7497 | const CallExpr *CE = tryUnwrapAllocSizeCall(Base); | |||
7498 | return getBytesReturnedByAllocSizeCall(Ctx, CE, Result); | |||
7499 | } | |||
7500 | ||||
7501 | /// Attempts to evaluate the given LValueBase as the result of a call to | |||
7502 | /// a function with the alloc_size attribute. If it was possible to do so, this | |||
7503 | /// function will return true, make Result's Base point to said function call, | |||
7504 | /// and mark Result's Base as invalid. | |||
7505 | static bool evaluateLValueAsAllocSize(EvalInfo &Info, APValue::LValueBase Base, | |||
7506 | LValue &Result) { | |||
7507 | if (Base.isNull()) | |||
7508 | return false; | |||
7509 | ||||
7510 | // Because we do no form of static analysis, we only support const variables. | |||
7511 | // | |||
7512 | // Additionally, we can't support parameters, nor can we support static | |||
7513 | // variables (in the latter case, use-before-assign isn't UB; in the former, | |||
7514 | // we have no clue what they'll be assigned to). | |||
7515 | const auto *VD = | |||
7516 | dyn_cast_or_null<VarDecl>(Base.dyn_cast<const ValueDecl *>()); | |||
7517 | if (!VD || !VD->isLocalVarDecl() || !VD->getType().isConstQualified()) | |||
7518 | return false; | |||
7519 | ||||
7520 | const Expr *Init = VD->getAnyInitializer(); | |||
7521 | if (!Init) | |||
7522 | return false; | |||
7523 | ||||
7524 | const Expr *E = Init->IgnoreParens(); | |||
7525 | if (!tryUnwrapAllocSizeCall(E)) | |||
7526 | return false; | |||
7527 | ||||
7528 | // Store E instead of E unwrapped so that the type of the LValue's base is | |||
7529 | // what the user wanted. | |||
7530 | Result.setInvalid(E); | |||
7531 | ||||
7532 | QualType Pointee = E->getType()->castAs<PointerType>()->getPointeeType(); | |||
7533 | Result.addUnsizedArray(Info, E, Pointee); | |||
7534 | return true; | |||
7535 | } | |||
7536 | ||||
7537 | namespace { | |||
7538 | class PointerExprEvaluator | |||
7539 | : public ExprEvaluatorBase<PointerExprEvaluator> { | |||
7540 | LValue &Result; | |||
7541 | bool InvalidBaseOK; | |||
7542 | ||||
7543 | bool Success(const Expr *E) { | |||
7544 | Result.set(E); | |||
7545 | return true; | |||
7546 | } | |||
7547 | ||||
7548 | bool evaluateLValue(const Expr *E, LValue &Result) { | |||
7549 | return EvaluateLValue(E, Result, Info, InvalidBaseOK); | |||
7550 | } | |||
7551 | ||||
7552 | bool evaluatePointer(const Expr *E, LValue &Result) { | |||
7553 | return EvaluatePointer(E, Result, Info, InvalidBaseOK); | |||
7554 | } | |||
7555 | ||||
7556 | bool visitNonBuiltinCallExpr(const CallExpr *E); | |||
7557 | public: | |||
7558 | ||||
7559 | PointerExprEvaluator(EvalInfo &info, LValue &Result, bool InvalidBaseOK) | |||
7560 | : ExprEvaluatorBaseTy(info), Result(Result), | |||
7561 | InvalidBaseOK(InvalidBaseOK) {} | |||
7562 | ||||
7563 | bool Success(const APValue &V, const Expr *E) { | |||
7564 | Result.setFrom(Info.Ctx, V); | |||
7565 | return true; | |||
7566 | } | |||
7567 | bool ZeroInitialization(const Expr *E) { | |||
7568 | auto TargetVal = Info.Ctx.getTargetNullPointerValue(E->getType()); | |||
7569 | Result.setNull(E->getType(), TargetVal); | |||
7570 | return true; | |||
7571 | } | |||
7572 | ||||
7573 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
7574 | bool VisitCastExpr(const CastExpr* E); | |||
7575 | bool VisitUnaryAddrOf(const UnaryOperator *E); | |||
7576 | bool VisitObjCStringLiteral(const ObjCStringLiteral *E) | |||
7577 | { return Success(E); } | |||
7578 | bool VisitObjCBoxedExpr(const ObjCBoxedExpr *E) { | |||
7579 | if (E->isExpressibleAsConstantInitializer()) | |||
7580 | return Success(E); | |||
7581 | if (Info.noteFailure()) | |||
7582 | EvaluateIgnoredValue(Info, E->getSubExpr()); | |||
7583 | return Error(E); | |||
7584 | } | |||
7585 | bool VisitAddrLabelExpr(const AddrLabelExpr *E) | |||
7586 | { return Success(E); } | |||
7587 | bool VisitCallExpr(const CallExpr *E); | |||
7588 | bool VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp); | |||
7589 | bool VisitBlockExpr(const BlockExpr *E) { | |||
7590 | if (!E->getBlockDecl()->hasCaptures()) | |||
7591 | return Success(E); | |||
7592 | return Error(E); | |||
7593 | } | |||
7594 | bool VisitCXXThisExpr(const CXXThisExpr *E) { | |||
7595 | // Can't look at 'this' when checking a potential constant expression. | |||
7596 | if (Info.checkingPotentialConstantExpression()) | |||
7597 | return false; | |||
7598 | if (!Info.CurrentCall->This) { | |||
7599 | if (Info.getLangOpts().CPlusPlus11) | |||
7600 | Info.FFDiag(E, diag::note_constexpr_this) << E->isImplicit(); | |||
7601 | else | |||
7602 | Info.FFDiag(E); | |||
7603 | return false; | |||
7604 | } | |||
7605 | Result = *Info.CurrentCall->This; | |||
7606 | // If we are inside a lambda's call operator, the 'this' expression refers | |||
7607 | // to the enclosing '*this' object (either by value or reference) which is | |||
7608 | // either copied into the closure object's field that represents the '*this' | |||
7609 | // or refers to '*this'. | |||
7610 | if (isLambdaCallOperator(Info.CurrentCall->Callee)) { | |||
7611 | // Update 'Result' to refer to the data member/field of the closure object | |||
7612 | // that represents the '*this' capture. | |||
7613 | if (!HandleLValueMember(Info, E, Result, | |||
7614 | Info.CurrentCall->LambdaThisCaptureField)) | |||
7615 | return false; | |||
7616 | // If we captured '*this' by reference, replace the field with its referent. | |||
7617 | if (Info.CurrentCall->LambdaThisCaptureField->getType() | |||
7618 | ->isPointerType()) { | |||
7619 | APValue RVal; | |||
7620 | if (!handleLValueToRValueConversion(Info, E, E->getType(), Result, | |||
7621 | RVal)) | |||
7622 | return false; | |||
7623 | ||||
7624 | Result.setFrom(Info.Ctx, RVal); | |||
7625 | } | |||
7626 | } | |||
7627 | return true; | |||
7628 | } | |||
7629 | ||||
7630 | bool VisitCXXNewExpr(const CXXNewExpr *E); | |||
7631 | ||||
7632 | bool VisitSourceLocExpr(const SourceLocExpr *E) { | |||
7633 | assert(E->isStringType() && "SourceLocExpr isn't a pointer type?")((E->isStringType() && "SourceLocExpr isn't a pointer type?" ) ? static_cast<void> (0) : __assert_fail ("E->isStringType() && \"SourceLocExpr isn't a pointer type?\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7633, __PRETTY_FUNCTION__)); | |||
7634 | APValue LValResult = E->EvaluateInContext( | |||
7635 | Info.Ctx, Info.CurrentCall->CurSourceLocExprScope.getDefaultExpr()); | |||
7636 | Result.setFrom(Info.Ctx, LValResult); | |||
7637 | return true; | |||
7638 | } | |||
7639 | ||||
7640 | // FIXME: Missing: @protocol, @selector | |||
7641 | }; | |||
7642 | } // end anonymous namespace | |||
7643 | ||||
7644 | static bool EvaluatePointer(const Expr* E, LValue& Result, EvalInfo &Info, | |||
7645 | bool InvalidBaseOK) { | |||
7646 | assert(E->isRValue() && E->getType()->hasPointerRepresentation())((E->isRValue() && E->getType()->hasPointerRepresentation ()) ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->hasPointerRepresentation()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7646, __PRETTY_FUNCTION__)); | |||
7647 | return PointerExprEvaluator(Info, Result, InvalidBaseOK).Visit(E); | |||
7648 | } | |||
7649 | ||||
7650 | bool PointerExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
7651 | if (E->getOpcode() != BO_Add && | |||
7652 | E->getOpcode() != BO_Sub) | |||
7653 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
7654 | ||||
7655 | const Expr *PExp = E->getLHS(); | |||
7656 | const Expr *IExp = E->getRHS(); | |||
7657 | if (IExp->getType()->isPointerType()) | |||
7658 | std::swap(PExp, IExp); | |||
7659 | ||||
7660 | bool EvalPtrOK = evaluatePointer(PExp, Result); | |||
7661 | if (!EvalPtrOK && !Info.noteFailure()) | |||
7662 | return false; | |||
7663 | ||||
7664 | llvm::APSInt Offset; | |||
7665 | if (!EvaluateInteger(IExp, Offset, Info) || !EvalPtrOK) | |||
7666 | return false; | |||
7667 | ||||
7668 | if (E->getOpcode() == BO_Sub) | |||
7669 | negateAsSigned(Offset); | |||
7670 | ||||
7671 | QualType Pointee = PExp->getType()->castAs<PointerType>()->getPointeeType(); | |||
7672 | return HandleLValueArrayAdjustment(Info, E, Result, Pointee, Offset); | |||
7673 | } | |||
7674 | ||||
7675 | bool PointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) { | |||
7676 | return evaluateLValue(E->getSubExpr(), Result); | |||
7677 | } | |||
7678 | ||||
7679 | bool PointerExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
7680 | const Expr *SubExpr = E->getSubExpr(); | |||
7681 | ||||
7682 | switch (E->getCastKind()) { | |||
7683 | default: | |||
7684 | break; | |||
7685 | case CK_BitCast: | |||
7686 | case CK_CPointerToObjCPointerCast: | |||
7687 | case CK_BlockPointerToObjCPointerCast: | |||
7688 | case CK_AnyPointerToBlockPointerCast: | |||
7689 | case CK_AddressSpaceConversion: | |||
7690 | if (!Visit(SubExpr)) | |||
7691 | return false; | |||
7692 | // Bitcasts to cv void* are static_casts, not reinterpret_casts, so are | |||
7693 | // permitted in constant expressions in C++11. Bitcasts from cv void* are | |||
7694 | // also static_casts, but we disallow them as a resolution to DR1312. | |||
7695 | if (!E->getType()->isVoidPointerType()) { | |||
7696 | Result.Designator.setInvalid(); | |||
7697 | if (SubExpr->getType()->isVoidPointerType()) | |||
7698 | CCEDiag(E, diag::note_constexpr_invalid_cast) | |||
7699 | << 3 << SubExpr->getType(); | |||
7700 | else | |||
7701 | CCEDiag(E, diag::note_constexpr_invalid_cast) << 2; | |||
7702 | } | |||
7703 | if (E->getCastKind() == CK_AddressSpaceConversion && Result.IsNullPtr) | |||
7704 | ZeroInitialization(E); | |||
7705 | return true; | |||
7706 | ||||
7707 | case CK_DerivedToBase: | |||
7708 | case CK_UncheckedDerivedToBase: | |||
7709 | if (!evaluatePointer(E->getSubExpr(), Result)) | |||
7710 | return false; | |||
7711 | if (!Result.Base && Result.Offset.isZero()) | |||
7712 | return true; | |||
7713 | ||||
7714 | // Now figure out the necessary offset to add to the base LV to get from | |||
7715 | // the derived class to the base class. | |||
7716 | return HandleLValueBasePath(Info, E, E->getSubExpr()->getType()-> | |||
7717 | castAs<PointerType>()->getPointeeType(), | |||
7718 | Result); | |||
7719 | ||||
7720 | case CK_BaseToDerived: | |||
7721 | if (!Visit(E->getSubExpr())) | |||
7722 | return false; | |||
7723 | if (!Result.Base && Result.Offset.isZero()) | |||
7724 | return true; | |||
7725 | return HandleBaseToDerivedCast(Info, E, Result); | |||
7726 | ||||
7727 | case CK_Dynamic: | |||
7728 | if (!Visit(E->getSubExpr())) | |||
7729 | return false; | |||
7730 | return HandleDynamicCast(Info, cast<ExplicitCastExpr>(E), Result); | |||
7731 | ||||
7732 | case CK_NullToPointer: | |||
7733 | VisitIgnoredValue(E->getSubExpr()); | |||
7734 | return ZeroInitialization(E); | |||
7735 | ||||
7736 | case CK_IntegralToPointer: { | |||
7737 | CCEDiag(E, diag::note_constexpr_invalid_cast) << 2; | |||
7738 | ||||
7739 | APValue Value; | |||
7740 | if (!EvaluateIntegerOrLValue(SubExpr, Value, Info)) | |||
7741 | break; | |||
7742 | ||||
7743 | if (Value.isInt()) { | |||
7744 | unsigned Size = Info.Ctx.getTypeSize(E->getType()); | |||
7745 | uint64_t N = Value.getInt().extOrTrunc(Size).getZExtValue(); | |||
7746 | Result.Base = (Expr*)nullptr; | |||
7747 | Result.InvalidBase = false; | |||
7748 | Result.Offset = CharUnits::fromQuantity(N); | |||
7749 | Result.Designator.setInvalid(); | |||
7750 | Result.IsNullPtr = false; | |||
7751 | return true; | |||
7752 | } else { | |||
7753 | // Cast is of an lvalue, no need to change value. | |||
7754 | Result.setFrom(Info.Ctx, Value); | |||
7755 | return true; | |||
7756 | } | |||
7757 | } | |||
7758 | ||||
7759 | case CK_ArrayToPointerDecay: { | |||
7760 | if (SubExpr->isGLValue()) { | |||
7761 | if (!evaluateLValue(SubExpr, Result)) | |||
7762 | return false; | |||
7763 | } else { | |||
7764 | APValue &Value = Info.CurrentCall->createTemporary( | |||
7765 | SubExpr, SubExpr->getType(), false, Result); | |||
7766 | if (!EvaluateInPlace(Value, Info, Result, SubExpr)) | |||
7767 | return false; | |||
7768 | } | |||
7769 | // The result is a pointer to the first element of the array. | |||
7770 | auto *AT = Info.Ctx.getAsArrayType(SubExpr->getType()); | |||
7771 | if (auto *CAT = dyn_cast<ConstantArrayType>(AT)) | |||
7772 | Result.addArray(Info, E, CAT); | |||
7773 | else | |||
7774 | Result.addUnsizedArray(Info, E, AT->getElementType()); | |||
7775 | return true; | |||
7776 | } | |||
7777 | ||||
7778 | case CK_FunctionToPointerDecay: | |||
7779 | return evaluateLValue(SubExpr, Result); | |||
7780 | ||||
7781 | case CK_LValueToRValue: { | |||
7782 | LValue LVal; | |||
7783 | if (!evaluateLValue(E->getSubExpr(), LVal)) | |||
7784 | return false; | |||
7785 | ||||
7786 | APValue RVal; | |||
7787 | // Note, we use the subexpression's type in order to retain cv-qualifiers. | |||
7788 | if (!handleLValueToRValueConversion(Info, E, E->getSubExpr()->getType(), | |||
7789 | LVal, RVal)) | |||
7790 | return InvalidBaseOK && | |||
7791 | evaluateLValueAsAllocSize(Info, LVal.Base, Result); | |||
7792 | return Success(RVal, E); | |||
7793 | } | |||
7794 | } | |||
7795 | ||||
7796 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
7797 | } | |||
7798 | ||||
7799 | static CharUnits GetAlignOfType(EvalInfo &Info, QualType T, | |||
7800 | UnaryExprOrTypeTrait ExprKind) { | |||
7801 | // C++ [expr.alignof]p3: | |||
7802 | // When alignof is applied to a reference type, the result is the | |||
7803 | // alignment of the referenced type. | |||
7804 | if (const ReferenceType *Ref = T->getAs<ReferenceType>()) | |||
7805 | T = Ref->getPointeeType(); | |||
7806 | ||||
7807 | if (T.getQualifiers().hasUnaligned()) | |||
7808 | return CharUnits::One(); | |||
7809 | ||||
7810 | const bool AlignOfReturnsPreferred = | |||
7811 | Info.Ctx.getLangOpts().getClangABICompat() <= LangOptions::ClangABI::Ver7; | |||
7812 | ||||
7813 | // __alignof is defined to return the preferred alignment. | |||
7814 | // Before 8, clang returned the preferred alignment for alignof and _Alignof | |||
7815 | // as well. | |||
7816 | if (ExprKind == UETT_PreferredAlignOf || AlignOfReturnsPreferred) | |||
7817 | return Info.Ctx.toCharUnitsFromBits( | |||
7818 | Info.Ctx.getPreferredTypeAlign(T.getTypePtr())); | |||
7819 | // alignof and _Alignof are defined to return the ABI alignment. | |||
7820 | else if (ExprKind == UETT_AlignOf) | |||
7821 | return Info.Ctx.getTypeAlignInChars(T.getTypePtr()); | |||
7822 | else | |||
7823 | llvm_unreachable("GetAlignOfType on a non-alignment ExprKind")::llvm::llvm_unreachable_internal("GetAlignOfType on a non-alignment ExprKind" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7823); | |||
7824 | } | |||
7825 | ||||
7826 | static CharUnits GetAlignOfExpr(EvalInfo &Info, const Expr *E, | |||
7827 | UnaryExprOrTypeTrait ExprKind) { | |||
7828 | E = E->IgnoreParens(); | |||
7829 | ||||
7830 | // The kinds of expressions that we have special-case logic here for | |||
7831 | // should be kept up to date with the special checks for those | |||
7832 | // expressions in Sema. | |||
7833 | ||||
7834 | // alignof decl is always accepted, even if it doesn't make sense: we default | |||
7835 | // to 1 in those cases. | |||
7836 | if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) | |||
7837 | return Info.Ctx.getDeclAlign(DRE->getDecl(), | |||
7838 | /*RefAsPointee*/true); | |||
7839 | ||||
7840 | if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) | |||
7841 | return Info.Ctx.getDeclAlign(ME->getMemberDecl(), | |||
7842 | /*RefAsPointee*/true); | |||
7843 | ||||
7844 | return GetAlignOfType(Info, E->getType(), ExprKind); | |||
7845 | } | |||
7846 | ||||
7847 | // To be clear: this happily visits unsupported builtins. Better name welcomed. | |||
7848 | bool PointerExprEvaluator::visitNonBuiltinCallExpr(const CallExpr *E) { | |||
7849 | if (ExprEvaluatorBaseTy::VisitCallExpr(E)) | |||
7850 | return true; | |||
7851 | ||||
7852 | if (!(InvalidBaseOK && getAllocSizeAttr(E))) | |||
7853 | return false; | |||
7854 | ||||
7855 | Result.setInvalid(E); | |||
7856 | QualType PointeeTy = E->getType()->castAs<PointerType>()->getPointeeType(); | |||
7857 | Result.addUnsizedArray(Info, E, PointeeTy); | |||
7858 | return true; | |||
7859 | } | |||
7860 | ||||
7861 | bool PointerExprEvaluator::VisitCallExpr(const CallExpr *E) { | |||
7862 | if (IsStringLiteralCall(E)) | |||
7863 | return Success(E); | |||
7864 | ||||
7865 | if (unsigned BuiltinOp = E->getBuiltinCallee()) | |||
7866 | return VisitBuiltinCallExpr(E, BuiltinOp); | |||
7867 | ||||
7868 | return visitNonBuiltinCallExpr(E); | |||
7869 | } | |||
7870 | ||||
7871 | bool PointerExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E, | |||
7872 | unsigned BuiltinOp) { | |||
7873 | switch (BuiltinOp) { | |||
7874 | case Builtin::BI__builtin_addressof: | |||
7875 | return evaluateLValue(E->getArg(0), Result); | |||
7876 | case Builtin::BI__builtin_assume_aligned: { | |||
7877 | // We need to be very careful here because: if the pointer does not have the | |||
7878 | // asserted alignment, then the behavior is undefined, and undefined | |||
7879 | // behavior is non-constant. | |||
7880 | if (!evaluatePointer(E->getArg(0), Result)) | |||
7881 | return false; | |||
7882 | ||||
7883 | LValue OffsetResult(Result); | |||
7884 | APSInt Alignment; | |||
7885 | if (!EvaluateInteger(E->getArg(1), Alignment, Info)) | |||
7886 | return false; | |||
7887 | CharUnits Align = CharUnits::fromQuantity(Alignment.getZExtValue()); | |||
7888 | ||||
7889 | if (E->getNumArgs() > 2) { | |||
7890 | APSInt Offset; | |||
7891 | if (!EvaluateInteger(E->getArg(2), Offset, Info)) | |||
7892 | return false; | |||
7893 | ||||
7894 | int64_t AdditionalOffset = -Offset.getZExtValue(); | |||
7895 | OffsetResult.Offset += CharUnits::fromQuantity(AdditionalOffset); | |||
7896 | } | |||
7897 | ||||
7898 | // If there is a base object, then it must have the correct alignment. | |||
7899 | if (OffsetResult.Base) { | |||
7900 | CharUnits BaseAlignment; | |||
7901 | if (const ValueDecl *VD = | |||
7902 | OffsetResult.Base.dyn_cast<const ValueDecl*>()) { | |||
7903 | BaseAlignment = Info.Ctx.getDeclAlign(VD); | |||
7904 | } else if (const Expr *E = OffsetResult.Base.dyn_cast<const Expr *>()) { | |||
7905 | BaseAlignment = GetAlignOfExpr(Info, E, UETT_AlignOf); | |||
7906 | } else { | |||
7907 | BaseAlignment = GetAlignOfType( | |||
7908 | Info, OffsetResult.Base.getTypeInfoType(), UETT_AlignOf); | |||
7909 | } | |||
7910 | ||||
7911 | if (BaseAlignment < Align) { | |||
7912 | Result.Designator.setInvalid(); | |||
7913 | // FIXME: Add support to Diagnostic for long / long long. | |||
7914 | CCEDiag(E->getArg(0), | |||
7915 | diag::note_constexpr_baa_insufficient_alignment) << 0 | |||
7916 | << (unsigned)BaseAlignment.getQuantity() | |||
7917 | << (unsigned)Align.getQuantity(); | |||
7918 | return false; | |||
7919 | } | |||
7920 | } | |||
7921 | ||||
7922 | // The offset must also have the correct alignment. | |||
7923 | if (OffsetResult.Offset.alignTo(Align) != OffsetResult.Offset) { | |||
7924 | Result.Designator.setInvalid(); | |||
7925 | ||||
7926 | (OffsetResult.Base | |||
7927 | ? CCEDiag(E->getArg(0), | |||
7928 | diag::note_constexpr_baa_insufficient_alignment) << 1 | |||
7929 | : CCEDiag(E->getArg(0), | |||
7930 | diag::note_constexpr_baa_value_insufficient_alignment)) | |||
7931 | << (int)OffsetResult.Offset.getQuantity() | |||
7932 | << (unsigned)Align.getQuantity(); | |||
7933 | return false; | |||
7934 | } | |||
7935 | ||||
7936 | return true; | |||
7937 | } | |||
7938 | case Builtin::BI__builtin_launder: | |||
7939 | return evaluatePointer(E->getArg(0), Result); | |||
7940 | case Builtin::BIstrchr: | |||
7941 | case Builtin::BIwcschr: | |||
7942 | case Builtin::BImemchr: | |||
7943 | case Builtin::BIwmemchr: | |||
7944 | if (Info.getLangOpts().CPlusPlus11) | |||
7945 | Info.CCEDiag(E, diag::note_constexpr_invalid_function) | |||
7946 | << /*isConstexpr*/0 << /*isConstructor*/0 | |||
7947 | << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'"); | |||
7948 | else | |||
7949 | Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
7950 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
7951 | case Builtin::BI__builtin_strchr: | |||
7952 | case Builtin::BI__builtin_wcschr: | |||
7953 | case Builtin::BI__builtin_memchr: | |||
7954 | case Builtin::BI__builtin_char_memchr: | |||
7955 | case Builtin::BI__builtin_wmemchr: { | |||
7956 | if (!Visit(E->getArg(0))) | |||
7957 | return false; | |||
7958 | APSInt Desired; | |||
7959 | if (!EvaluateInteger(E->getArg(1), Desired, Info)) | |||
7960 | return false; | |||
7961 | uint64_t MaxLength = uint64_t(-1); | |||
7962 | if (BuiltinOp != Builtin::BIstrchr && | |||
7963 | BuiltinOp != Builtin::BIwcschr && | |||
7964 | BuiltinOp != Builtin::BI__builtin_strchr && | |||
7965 | BuiltinOp != Builtin::BI__builtin_wcschr) { | |||
7966 | APSInt N; | |||
7967 | if (!EvaluateInteger(E->getArg(2), N, Info)) | |||
7968 | return false; | |||
7969 | MaxLength = N.getExtValue(); | |||
7970 | } | |||
7971 | // We cannot find the value if there are no candidates to match against. | |||
7972 | if (MaxLength == 0u) | |||
7973 | return ZeroInitialization(E); | |||
7974 | if (!Result.checkNullPointerForFoldAccess(Info, E, AK_Read) || | |||
7975 | Result.Designator.Invalid) | |||
7976 | return false; | |||
7977 | QualType CharTy = Result.Designator.getType(Info.Ctx); | |||
7978 | bool IsRawByte = BuiltinOp == Builtin::BImemchr || | |||
7979 | BuiltinOp == Builtin::BI__builtin_memchr; | |||
7980 | assert(IsRawByte ||((IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E-> getArg(0)->getType()->getPointeeType())) ? static_cast< void> (0) : __assert_fail ("IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E->getArg(0)->getType()->getPointeeType())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7982, __PRETTY_FUNCTION__)) | |||
7981 | Info.Ctx.hasSameUnqualifiedType(((IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E-> getArg(0)->getType()->getPointeeType())) ? static_cast< void> (0) : __assert_fail ("IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E->getArg(0)->getType()->getPointeeType())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7982, __PRETTY_FUNCTION__)) | |||
7982 | CharTy, E->getArg(0)->getType()->getPointeeType()))((IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E-> getArg(0)->getType()->getPointeeType())) ? static_cast< void> (0) : __assert_fail ("IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E->getArg(0)->getType()->getPointeeType())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 7982, __PRETTY_FUNCTION__)); | |||
7983 | // Pointers to const void may point to objects of incomplete type. | |||
7984 | if (IsRawByte && CharTy->isIncompleteType()) { | |||
7985 | Info.FFDiag(E, diag::note_constexpr_ltor_incomplete_type) << CharTy; | |||
7986 | return false; | |||
7987 | } | |||
7988 | // Give up on byte-oriented matching against multibyte elements. | |||
7989 | // FIXME: We can compare the bytes in the correct order. | |||
7990 | if (IsRawByte && Info.Ctx.getTypeSizeInChars(CharTy) != CharUnits::One()) | |||
7991 | return false; | |||
7992 | // Figure out what value we're actually looking for (after converting to | |||
7993 | // the corresponding unsigned type if necessary). | |||
7994 | uint64_t DesiredVal; | |||
7995 | bool StopAtNull = false; | |||
7996 | switch (BuiltinOp) { | |||
7997 | case Builtin::BIstrchr: | |||
7998 | case Builtin::BI__builtin_strchr: | |||
7999 | // strchr compares directly to the passed integer, and therefore | |||
8000 | // always fails if given an int that is not a char. | |||
8001 | if (!APSInt::isSameValue(HandleIntToIntCast(Info, E, CharTy, | |||
8002 | E->getArg(1)->getType(), | |||
8003 | Desired), | |||
8004 | Desired)) | |||
8005 | return ZeroInitialization(E); | |||
8006 | StopAtNull = true; | |||
8007 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
8008 | case Builtin::BImemchr: | |||
8009 | case Builtin::BI__builtin_memchr: | |||
8010 | case Builtin::BI__builtin_char_memchr: | |||
8011 | // memchr compares by converting both sides to unsigned char. That's also | |||
8012 | // correct for strchr if we get this far (to cope with plain char being | |||
8013 | // unsigned in the strchr case). | |||
8014 | DesiredVal = Desired.trunc(Info.Ctx.getCharWidth()).getZExtValue(); | |||
8015 | break; | |||
8016 | ||||
8017 | case Builtin::BIwcschr: | |||
8018 | case Builtin::BI__builtin_wcschr: | |||
8019 | StopAtNull = true; | |||
8020 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
8021 | case Builtin::BIwmemchr: | |||
8022 | case Builtin::BI__builtin_wmemchr: | |||
8023 | // wcschr and wmemchr are given a wchar_t to look for. Just use it. | |||
8024 | DesiredVal = Desired.getZExtValue(); | |||
8025 | break; | |||
8026 | } | |||
8027 | ||||
8028 | for (; MaxLength; --MaxLength) { | |||
8029 | APValue Char; | |||
8030 | if (!handleLValueToRValueConversion(Info, E, CharTy, Result, Char) || | |||
8031 | !Char.isInt()) | |||
8032 | return false; | |||
8033 | if (Char.getInt().getZExtValue() == DesiredVal) | |||
8034 | return true; | |||
8035 | if (StopAtNull && !Char.getInt()) | |||
8036 | break; | |||
8037 | if (!HandleLValueArrayAdjustment(Info, E, Result, CharTy, 1)) | |||
8038 | return false; | |||
8039 | } | |||
8040 | // Not found: return nullptr. | |||
8041 | return ZeroInitialization(E); | |||
8042 | } | |||
8043 | ||||
8044 | case Builtin::BImemcpy: | |||
8045 | case Builtin::BImemmove: | |||
8046 | case Builtin::BIwmemcpy: | |||
8047 | case Builtin::BIwmemmove: | |||
8048 | if (Info.getLangOpts().CPlusPlus11) | |||
8049 | Info.CCEDiag(E, diag::note_constexpr_invalid_function) | |||
8050 | << /*isConstexpr*/0 << /*isConstructor*/0 | |||
8051 | << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'"); | |||
8052 | else | |||
8053 | Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
8054 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
8055 | case Builtin::BI__builtin_memcpy: | |||
8056 | case Builtin::BI__builtin_memmove: | |||
8057 | case Builtin::BI__builtin_wmemcpy: | |||
8058 | case Builtin::BI__builtin_wmemmove: { | |||
8059 | bool WChar = BuiltinOp == Builtin::BIwmemcpy || | |||
8060 | BuiltinOp == Builtin::BIwmemmove || | |||
8061 | BuiltinOp == Builtin::BI__builtin_wmemcpy || | |||
8062 | BuiltinOp == Builtin::BI__builtin_wmemmove; | |||
8063 | bool Move = BuiltinOp == Builtin::BImemmove || | |||
8064 | BuiltinOp == Builtin::BIwmemmove || | |||
8065 | BuiltinOp == Builtin::BI__builtin_memmove || | |||
8066 | BuiltinOp == Builtin::BI__builtin_wmemmove; | |||
8067 | ||||
8068 | // The result of mem* is the first argument. | |||
8069 | if (!Visit(E->getArg(0))) | |||
8070 | return false; | |||
8071 | LValue Dest = Result; | |||
8072 | ||||
8073 | LValue Src; | |||
8074 | if (!EvaluatePointer(E->getArg(1), Src, Info)) | |||
8075 | return false; | |||
8076 | ||||
8077 | APSInt N; | |||
8078 | if (!EvaluateInteger(E->getArg(2), N, Info)) | |||
8079 | return false; | |||
8080 | assert(!N.isSigned() && "memcpy and friends take an unsigned size")((!N.isSigned() && "memcpy and friends take an unsigned size" ) ? static_cast<void> (0) : __assert_fail ("!N.isSigned() && \"memcpy and friends take an unsigned size\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8080, __PRETTY_FUNCTION__)); | |||
8081 | ||||
8082 | // If the size is zero, we treat this as always being a valid no-op. | |||
8083 | // (Even if one of the src and dest pointers is null.) | |||
8084 | if (!N) | |||
8085 | return true; | |||
8086 | ||||
8087 | // Otherwise, if either of the operands is null, we can't proceed. Don't | |||
8088 | // try to determine the type of the copied objects, because there aren't | |||
8089 | // any. | |||
8090 | if (!Src.Base || !Dest.Base) { | |||
8091 | APValue Val; | |||
8092 | (!Src.Base ? Src : Dest).moveInto(Val); | |||
8093 | Info.FFDiag(E, diag::note_constexpr_memcpy_null) | |||
8094 | << Move << WChar << !!Src.Base | |||
8095 | << Val.getAsString(Info.Ctx, E->getArg(0)->getType()); | |||
8096 | return false; | |||
8097 | } | |||
8098 | if (Src.Designator.Invalid || Dest.Designator.Invalid) | |||
8099 | return false; | |||
8100 | ||||
8101 | // We require that Src and Dest are both pointers to arrays of | |||
8102 | // trivially-copyable type. (For the wide version, the designator will be | |||
8103 | // invalid if the designated object is not a wchar_t.) | |||
8104 | QualType T = Dest.Designator.getType(Info.Ctx); | |||
8105 | QualType SrcT = Src.Designator.getType(Info.Ctx); | |||
8106 | if (!Info.Ctx.hasSameUnqualifiedType(T, SrcT)) { | |||
8107 | Info.FFDiag(E, diag::note_constexpr_memcpy_type_pun) << Move << SrcT << T; | |||
8108 | return false; | |||
8109 | } | |||
8110 | if (T->isIncompleteType()) { | |||
8111 | Info.FFDiag(E, diag::note_constexpr_memcpy_incomplete_type) << Move << T; | |||
8112 | return false; | |||
8113 | } | |||
8114 | if (!T.isTriviallyCopyableType(Info.Ctx)) { | |||
8115 | Info.FFDiag(E, diag::note_constexpr_memcpy_nontrivial) << Move << T; | |||
8116 | return false; | |||
8117 | } | |||
8118 | ||||
8119 | // Figure out how many T's we're copying. | |||
8120 | uint64_t TSize = Info.Ctx.getTypeSizeInChars(T).getQuantity(); | |||
8121 | if (!WChar) { | |||
8122 | uint64_t Remainder; | |||
8123 | llvm::APInt OrigN = N; | |||
8124 | llvm::APInt::udivrem(OrigN, TSize, N, Remainder); | |||
8125 | if (Remainder) { | |||
8126 | Info.FFDiag(E, diag::note_constexpr_memcpy_unsupported) | |||
8127 | << Move << WChar << 0 << T << OrigN.toString(10, /*Signed*/false) | |||
8128 | << (unsigned)TSize; | |||
8129 | return false; | |||
8130 | } | |||
8131 | } | |||
8132 | ||||
8133 | // Check that the copying will remain within the arrays, just so that we | |||
8134 | // can give a more meaningful diagnostic. This implicitly also checks that | |||
8135 | // N fits into 64 bits. | |||
8136 | uint64_t RemainingSrcSize = Src.Designator.validIndexAdjustments().second; | |||
8137 | uint64_t RemainingDestSize = Dest.Designator.validIndexAdjustments().second; | |||
8138 | if (N.ugt(RemainingSrcSize) || N.ugt(RemainingDestSize)) { | |||
8139 | Info.FFDiag(E, diag::note_constexpr_memcpy_unsupported) | |||
8140 | << Move << WChar << (N.ugt(RemainingSrcSize) ? 1 : 2) << T | |||
8141 | << N.toString(10, /*Signed*/false); | |||
8142 | return false; | |||
8143 | } | |||
8144 | uint64_t NElems = N.getZExtValue(); | |||
8145 | uint64_t NBytes = NElems * TSize; | |||
8146 | ||||
8147 | // Check for overlap. | |||
8148 | int Direction = 1; | |||
8149 | if (HasSameBase(Src, Dest)) { | |||
8150 | uint64_t SrcOffset = Src.getLValueOffset().getQuantity(); | |||
8151 | uint64_t DestOffset = Dest.getLValueOffset().getQuantity(); | |||
8152 | if (DestOffset >= SrcOffset && DestOffset - SrcOffset < NBytes) { | |||
8153 | // Dest is inside the source region. | |||
8154 | if (!Move) { | |||
8155 | Info.FFDiag(E, diag::note_constexpr_memcpy_overlap) << WChar; | |||
8156 | return false; | |||
8157 | } | |||
8158 | // For memmove and friends, copy backwards. | |||
8159 | if (!HandleLValueArrayAdjustment(Info, E, Src, T, NElems - 1) || | |||
8160 | !HandleLValueArrayAdjustment(Info, E, Dest, T, NElems - 1)) | |||
8161 | return false; | |||
8162 | Direction = -1; | |||
8163 | } else if (!Move && SrcOffset >= DestOffset && | |||
8164 | SrcOffset - DestOffset < NBytes) { | |||
8165 | // Src is inside the destination region for memcpy: invalid. | |||
8166 | Info.FFDiag(E, diag::note_constexpr_memcpy_overlap) << WChar; | |||
8167 | return false; | |||
8168 | } | |||
8169 | } | |||
8170 | ||||
8171 | while (true) { | |||
8172 | APValue Val; | |||
8173 | // FIXME: Set WantObjectRepresentation to true if we're copying a | |||
8174 | // char-like type? | |||
8175 | if (!handleLValueToRValueConversion(Info, E, T, Src, Val) || | |||
8176 | !handleAssignment(Info, E, Dest, T, Val)) | |||
8177 | return false; | |||
8178 | // Do not iterate past the last element; if we're copying backwards, that | |||
8179 | // might take us off the start of the array. | |||
8180 | if (--NElems == 0) | |||
8181 | return true; | |||
8182 | if (!HandleLValueArrayAdjustment(Info, E, Src, T, Direction) || | |||
8183 | !HandleLValueArrayAdjustment(Info, E, Dest, T, Direction)) | |||
8184 | return false; | |||
8185 | } | |||
8186 | } | |||
8187 | ||||
8188 | default: | |||
8189 | return visitNonBuiltinCallExpr(E); | |||
8190 | } | |||
8191 | } | |||
8192 | ||||
8193 | static bool EvaluateArrayNewInitList(EvalInfo &Info, LValue &This, | |||
8194 | APValue &Result, const InitListExpr *ILE, | |||
8195 | QualType AllocType); | |||
8196 | ||||
8197 | bool PointerExprEvaluator::VisitCXXNewExpr(const CXXNewExpr *E) { | |||
8198 | if (!Info.getLangOpts().CPlusPlus2a) | |||
8199 | Info.CCEDiag(E, diag::note_constexpr_new); | |||
8200 | ||||
8201 | // We cannot speculatively evaluate a delete expression. | |||
8202 | if (Info.SpeculativeEvaluationDepth) | |||
8203 | return false; | |||
8204 | ||||
8205 | FunctionDecl *OperatorNew = E->getOperatorNew(); | |||
8206 | if (!OperatorNew->isReplaceableGlobalAllocationFunction()) { | |||
8207 | Info.FFDiag(E, diag::note_constexpr_new_non_replaceable) | |||
8208 | << isa<CXXMethodDecl>(OperatorNew) << OperatorNew; | |||
8209 | return false; | |||
8210 | } | |||
8211 | ||||
8212 | bool IsNothrow = false; | |||
8213 | if (E->getNumPlacementArgs()) { | |||
8214 | // The only new-placement list we support is of the form (std::nothrow). | |||
8215 | // | |||
8216 | // FIXME: There is no restriction on this, but it's not clear that any | |||
8217 | // other form makes any sense. We get here for cases such as: | |||
8218 | // | |||
8219 | // new (std::align_val_t{N}) X(int) | |||
8220 | // | |||
8221 | // (which should presumably be valid only if N is a multiple of | |||
8222 | // alignof(int), and in any case can't be deallocated unless N is | |||
8223 | // alignof(X) and X has new-extended alignment). | |||
8224 | if (E->getNumPlacementArgs() != 1 || | |||
8225 | !E->getPlacementArg(0)->getType()->isNothrowT()) | |||
8226 | return Error(E, diag::note_constexpr_new_placement); | |||
8227 | ||||
8228 | LValue Nothrow; | |||
8229 | if (!EvaluateLValue(E->getPlacementArg(0), Nothrow, Info)) | |||
8230 | return false; | |||
8231 | IsNothrow = true; | |||
8232 | } | |||
8233 | ||||
8234 | const Expr *Init = E->getInitializer(); | |||
8235 | const InitListExpr *ResizedArrayILE = nullptr; | |||
8236 | ||||
8237 | QualType AllocType = E->getAllocatedType(); | |||
8238 | if (Optional<const Expr*> ArraySize = E->getArraySize()) { | |||
8239 | const Expr *Stripped = *ArraySize; | |||
8240 | for (; auto *ICE = dyn_cast<ImplicitCastExpr>(Stripped); | |||
8241 | Stripped = ICE->getSubExpr()) | |||
8242 | if (ICE->getCastKind() != CK_NoOp && | |||
8243 | ICE->getCastKind() != CK_IntegralCast) | |||
8244 | break; | |||
8245 | ||||
8246 | llvm::APSInt ArrayBound; | |||
8247 | if (!EvaluateInteger(Stripped, ArrayBound, Info)) | |||
8248 | return false; | |||
8249 | ||||
8250 | // C++ [expr.new]p9: | |||
8251 | // The expression is erroneous if: | |||
8252 | // -- [...] its value before converting to size_t [or] applying the | |||
8253 | // second standard conversion sequence is less than zero | |||
8254 | if (ArrayBound.isSigned() && ArrayBound.isNegative()) { | |||
8255 | if (IsNothrow) | |||
8256 | return ZeroInitialization(E); | |||
8257 | ||||
8258 | Info.FFDiag(*ArraySize, diag::note_constexpr_new_negative) | |||
8259 | << ArrayBound << (*ArraySize)->getSourceRange(); | |||
8260 | return false; | |||
8261 | } | |||
8262 | ||||
8263 | // -- its value is such that the size of the allocated object would | |||
8264 | // exceed the implementation-defined limit | |||
8265 | if (ConstantArrayType::getNumAddressingBits(Info.Ctx, AllocType, | |||
8266 | ArrayBound) > | |||
8267 | ConstantArrayType::getMaxSizeBits(Info.Ctx)) { | |||
8268 | if (IsNothrow) | |||
8269 | return ZeroInitialization(E); | |||
8270 | ||||
8271 | Info.FFDiag(*ArraySize, diag::note_constexpr_new_too_large) | |||
8272 | << ArrayBound << (*ArraySize)->getSourceRange(); | |||
8273 | return false; | |||
8274 | } | |||
8275 | ||||
8276 | // -- the new-initializer is a braced-init-list and the number of | |||
8277 | // array elements for which initializers are provided [...] | |||
8278 | // exceeds the number of elements to initialize | |||
8279 | if (Init) { | |||
8280 | auto *CAT = Info.Ctx.getAsConstantArrayType(Init->getType()); | |||
8281 | assert(CAT && "unexpected type for array initializer")((CAT && "unexpected type for array initializer") ? static_cast <void> (0) : __assert_fail ("CAT && \"unexpected type for array initializer\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8281, __PRETTY_FUNCTION__)); | |||
8282 | ||||
8283 | unsigned Bits = | |||
8284 | std::max(CAT->getSize().getBitWidth(), ArrayBound.getBitWidth()); | |||
8285 | llvm::APInt InitBound = CAT->getSize().zextOrSelf(Bits); | |||
8286 | llvm::APInt AllocBound = ArrayBound.zextOrSelf(Bits); | |||
8287 | if (InitBound.ugt(AllocBound)) { | |||
8288 | if (IsNothrow) | |||
8289 | return ZeroInitialization(E); | |||
8290 | ||||
8291 | Info.FFDiag(*ArraySize, diag::note_constexpr_new_too_small) | |||
8292 | << AllocBound.toString(10, /*Signed=*/false) | |||
8293 | << InitBound.toString(10, /*Signed=*/false) | |||
8294 | << (*ArraySize)->getSourceRange(); | |||
8295 | return false; | |||
8296 | } | |||
8297 | ||||
8298 | // If the sizes differ, we must have an initializer list, and we need | |||
8299 | // special handling for this case when we initialize. | |||
8300 | if (InitBound != AllocBound) | |||
8301 | ResizedArrayILE = cast<InitListExpr>(Init); | |||
8302 | } | |||
8303 | ||||
8304 | AllocType = Info.Ctx.getConstantArrayType(AllocType, ArrayBound, | |||
8305 | ArrayType::Normal, 0); | |||
8306 | } else { | |||
8307 | assert(!AllocType->isArrayType() &&((!AllocType->isArrayType() && "array allocation with non-array new" ) ? static_cast<void> (0) : __assert_fail ("!AllocType->isArrayType() && \"array allocation with non-array new\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8308, __PRETTY_FUNCTION__)) | |||
8308 | "array allocation with non-array new")((!AllocType->isArrayType() && "array allocation with non-array new" ) ? static_cast<void> (0) : __assert_fail ("!AllocType->isArrayType() && \"array allocation with non-array new\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8308, __PRETTY_FUNCTION__)); | |||
8309 | } | |||
8310 | ||||
8311 | // Perform the allocation and obtain a pointer to the resulting object. | |||
8312 | APValue *Val = Info.createHeapAlloc(E, AllocType, Result); | |||
8313 | if (!Val) | |||
8314 | return false; | |||
8315 | ||||
8316 | if (ResizedArrayILE) { | |||
8317 | if (!EvaluateArrayNewInitList(Info, Result, *Val, ResizedArrayILE, | |||
8318 | AllocType)) | |||
8319 | return false; | |||
8320 | } else if (Init) { | |||
8321 | if (!EvaluateInPlace(*Val, Info, Result, Init)) | |||
8322 | return false; | |||
8323 | } else { | |||
8324 | *Val = getDefaultInitValue(AllocType); | |||
8325 | } | |||
8326 | ||||
8327 | // Array new returns a pointer to the first element, not a pointer to the | |||
8328 | // array. | |||
8329 | if (auto *AT = AllocType->getAsArrayTypeUnsafe()) | |||
8330 | Result.addArray(Info, E, cast<ConstantArrayType>(AT)); | |||
8331 | ||||
8332 | return true; | |||
8333 | } | |||
8334 | //===----------------------------------------------------------------------===// | |||
8335 | // Member Pointer Evaluation | |||
8336 | //===----------------------------------------------------------------------===// | |||
8337 | ||||
8338 | namespace { | |||
8339 | class MemberPointerExprEvaluator | |||
8340 | : public ExprEvaluatorBase<MemberPointerExprEvaluator> { | |||
8341 | MemberPtr &Result; | |||
8342 | ||||
8343 | bool Success(const ValueDecl *D) { | |||
8344 | Result = MemberPtr(D); | |||
8345 | return true; | |||
8346 | } | |||
8347 | public: | |||
8348 | ||||
8349 | MemberPointerExprEvaluator(EvalInfo &Info, MemberPtr &Result) | |||
8350 | : ExprEvaluatorBaseTy(Info), Result(Result) {} | |||
8351 | ||||
8352 | bool Success(const APValue &V, const Expr *E) { | |||
8353 | Result.setFrom(V); | |||
8354 | return true; | |||
8355 | } | |||
8356 | bool ZeroInitialization(const Expr *E) { | |||
8357 | return Success((const ValueDecl*)nullptr); | |||
8358 | } | |||
8359 | ||||
8360 | bool VisitCastExpr(const CastExpr *E); | |||
8361 | bool VisitUnaryAddrOf(const UnaryOperator *E); | |||
8362 | }; | |||
8363 | } // end anonymous namespace | |||
8364 | ||||
8365 | static bool EvaluateMemberPointer(const Expr *E, MemberPtr &Result, | |||
8366 | EvalInfo &Info) { | |||
8367 | assert(E->isRValue() && E->getType()->isMemberPointerType())((E->isRValue() && E->getType()->isMemberPointerType ()) ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isMemberPointerType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8367, __PRETTY_FUNCTION__)); | |||
8368 | return MemberPointerExprEvaluator(Info, Result).Visit(E); | |||
8369 | } | |||
8370 | ||||
8371 | bool MemberPointerExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
8372 | switch (E->getCastKind()) { | |||
8373 | default: | |||
8374 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
8375 | ||||
8376 | case CK_NullToMemberPointer: | |||
8377 | VisitIgnoredValue(E->getSubExpr()); | |||
8378 | return ZeroInitialization(E); | |||
8379 | ||||
8380 | case CK_BaseToDerivedMemberPointer: { | |||
8381 | if (!Visit(E->getSubExpr())) | |||
8382 | return false; | |||
8383 | if (E->path_empty()) | |||
8384 | return true; | |||
8385 | // Base-to-derived member pointer casts store the path in derived-to-base | |||
8386 | // order, so iterate backwards. The CXXBaseSpecifier also provides us with | |||
8387 | // the wrong end of the derived->base arc, so stagger the path by one class. | |||
8388 | typedef std::reverse_iterator<CastExpr::path_const_iterator> ReverseIter; | |||
8389 | for (ReverseIter PathI(E->path_end() - 1), PathE(E->path_begin()); | |||
8390 | PathI != PathE; ++PathI) { | |||
8391 | assert(!(*PathI)->isVirtual() && "memptr cast through vbase")((!(*PathI)->isVirtual() && "memptr cast through vbase" ) ? static_cast<void> (0) : __assert_fail ("!(*PathI)->isVirtual() && \"memptr cast through vbase\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8391, __PRETTY_FUNCTION__)); | |||
8392 | const CXXRecordDecl *Derived = (*PathI)->getType()->getAsCXXRecordDecl(); | |||
8393 | if (!Result.castToDerived(Derived)) | |||
8394 | return Error(E); | |||
8395 | } | |||
8396 | const Type *FinalTy = E->getType()->castAs<MemberPointerType>()->getClass(); | |||
8397 | if (!Result.castToDerived(FinalTy->getAsCXXRecordDecl())) | |||
8398 | return Error(E); | |||
8399 | return true; | |||
8400 | } | |||
8401 | ||||
8402 | case CK_DerivedToBaseMemberPointer: | |||
8403 | if (!Visit(E->getSubExpr())) | |||
8404 | return false; | |||
8405 | for (CastExpr::path_const_iterator PathI = E->path_begin(), | |||
8406 | PathE = E->path_end(); PathI != PathE; ++PathI) { | |||
8407 | assert(!(*PathI)->isVirtual() && "memptr cast through vbase")((!(*PathI)->isVirtual() && "memptr cast through vbase" ) ? static_cast<void> (0) : __assert_fail ("!(*PathI)->isVirtual() && \"memptr cast through vbase\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8407, __PRETTY_FUNCTION__)); | |||
8408 | const CXXRecordDecl *Base = (*PathI)->getType()->getAsCXXRecordDecl(); | |||
8409 | if (!Result.castToBase(Base)) | |||
8410 | return Error(E); | |||
8411 | } | |||
8412 | return true; | |||
8413 | } | |||
8414 | } | |||
8415 | ||||
8416 | bool MemberPointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) { | |||
8417 | // C++11 [expr.unary.op]p3 has very strict rules on how the address of a | |||
8418 | // member can be formed. | |||
8419 | return Success(cast<DeclRefExpr>(E->getSubExpr())->getDecl()); | |||
8420 | } | |||
8421 | ||||
8422 | //===----------------------------------------------------------------------===// | |||
8423 | // Record Evaluation | |||
8424 | //===----------------------------------------------------------------------===// | |||
8425 | ||||
8426 | namespace { | |||
8427 | class RecordExprEvaluator | |||
8428 | : public ExprEvaluatorBase<RecordExprEvaluator> { | |||
8429 | const LValue &This; | |||
8430 | APValue &Result; | |||
8431 | public: | |||
8432 | ||||
8433 | RecordExprEvaluator(EvalInfo &info, const LValue &This, APValue &Result) | |||
8434 | : ExprEvaluatorBaseTy(info), This(This), Result(Result) {} | |||
8435 | ||||
8436 | bool Success(const APValue &V, const Expr *E) { | |||
8437 | Result = V; | |||
8438 | return true; | |||
8439 | } | |||
8440 | bool ZeroInitialization(const Expr *E) { | |||
8441 | return ZeroInitialization(E, E->getType()); | |||
8442 | } | |||
8443 | bool ZeroInitialization(const Expr *E, QualType T); | |||
8444 | ||||
8445 | bool VisitCallExpr(const CallExpr *E) { | |||
8446 | return handleCallExpr(E, Result, &This); | |||
8447 | } | |||
8448 | bool VisitCastExpr(const CastExpr *E); | |||
8449 | bool VisitInitListExpr(const InitListExpr *E); | |||
8450 | bool VisitCXXConstructExpr(const CXXConstructExpr *E) { | |||
8451 | return VisitCXXConstructExpr(E, E->getType()); | |||
8452 | } | |||
8453 | bool VisitLambdaExpr(const LambdaExpr *E); | |||
8454 | bool VisitCXXInheritedCtorInitExpr(const CXXInheritedCtorInitExpr *E); | |||
8455 | bool VisitCXXConstructExpr(const CXXConstructExpr *E, QualType T); | |||
8456 | bool VisitCXXStdInitializerListExpr(const CXXStdInitializerListExpr *E); | |||
8457 | bool VisitBinCmp(const BinaryOperator *E); | |||
8458 | }; | |||
8459 | } | |||
8460 | ||||
8461 | /// Perform zero-initialization on an object of non-union class type. | |||
8462 | /// C++11 [dcl.init]p5: | |||
8463 | /// To zero-initialize an object or reference of type T means: | |||
8464 | /// [...] | |||
8465 | /// -- if T is a (possibly cv-qualified) non-union class type, | |||
8466 | /// each non-static data member and each base-class subobject is | |||
8467 | /// zero-initialized | |||
8468 | static bool HandleClassZeroInitialization(EvalInfo &Info, const Expr *E, | |||
8469 | const RecordDecl *RD, | |||
8470 | const LValue &This, APValue &Result) { | |||
8471 | assert(!RD->isUnion() && "Expected non-union class type")((!RD->isUnion() && "Expected non-union class type" ) ? static_cast<void> (0) : __assert_fail ("!RD->isUnion() && \"Expected non-union class type\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8471, __PRETTY_FUNCTION__)); | |||
8472 | const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD); | |||
8473 | Result = APValue(APValue::UninitStruct(), CD ? CD->getNumBases() : 0, | |||
8474 | std::distance(RD->field_begin(), RD->field_end())); | |||
8475 | ||||
8476 | if (RD->isInvalidDecl()) return false; | |||
8477 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
8478 | ||||
8479 | if (CD) { | |||
8480 | unsigned Index = 0; | |||
8481 | for (CXXRecordDecl::base_class_const_iterator I = CD->bases_begin(), | |||
8482 | End = CD->bases_end(); I != End; ++I, ++Index) { | |||
8483 | const CXXRecordDecl *Base = I->getType()->getAsCXXRecordDecl(); | |||
8484 | LValue Subobject = This; | |||
8485 | if (!HandleLValueDirectBase(Info, E, Subobject, CD, Base, &Layout)) | |||
8486 | return false; | |||
8487 | if (!HandleClassZeroInitialization(Info, E, Base, Subobject, | |||
8488 | Result.getStructBase(Index))) | |||
8489 | return false; | |||
8490 | } | |||
8491 | } | |||
8492 | ||||
8493 | for (const auto *I : RD->fields()) { | |||
8494 | // -- if T is a reference type, no initialization is performed. | |||
8495 | if (I->getType()->isReferenceType()) | |||
8496 | continue; | |||
8497 | ||||
8498 | LValue Subobject = This; | |||
8499 | if (!HandleLValueMember(Info, E, Subobject, I, &Layout)) | |||
8500 | return false; | |||
8501 | ||||
8502 | ImplicitValueInitExpr VIE(I->getType()); | |||
8503 | if (!EvaluateInPlace( | |||
8504 | Result.getStructField(I->getFieldIndex()), Info, Subobject, &VIE)) | |||
8505 | return false; | |||
8506 | } | |||
8507 | ||||
8508 | return true; | |||
8509 | } | |||
8510 | ||||
8511 | bool RecordExprEvaluator::ZeroInitialization(const Expr *E, QualType T) { | |||
8512 | const RecordDecl *RD = T->castAs<RecordType>()->getDecl(); | |||
8513 | if (RD->isInvalidDecl()) return false; | |||
8514 | if (RD->isUnion()) { | |||
8515 | // C++11 [dcl.init]p5: If T is a (possibly cv-qualified) union type, the | |||
8516 | // object's first non-static named data member is zero-initialized | |||
8517 | RecordDecl::field_iterator I = RD->field_begin(); | |||
8518 | if (I == RD->field_end()) { | |||
8519 | Result = APValue((const FieldDecl*)nullptr); | |||
8520 | return true; | |||
8521 | } | |||
8522 | ||||
8523 | LValue Subobject = This; | |||
8524 | if (!HandleLValueMember(Info, E, Subobject, *I)) | |||
8525 | return false; | |||
8526 | Result = APValue(*I); | |||
8527 | ImplicitValueInitExpr VIE(I->getType()); | |||
8528 | return EvaluateInPlace(Result.getUnionValue(), Info, Subobject, &VIE); | |||
8529 | } | |||
8530 | ||||
8531 | if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->getNumVBases()) { | |||
8532 | Info.FFDiag(E, diag::note_constexpr_virtual_base) << RD; | |||
8533 | return false; | |||
8534 | } | |||
8535 | ||||
8536 | return HandleClassZeroInitialization(Info, E, RD, This, Result); | |||
8537 | } | |||
8538 | ||||
8539 | bool RecordExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
8540 | switch (E->getCastKind()) { | |||
8541 | default: | |||
8542 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
8543 | ||||
8544 | case CK_ConstructorConversion: | |||
8545 | return Visit(E->getSubExpr()); | |||
8546 | ||||
8547 | case CK_DerivedToBase: | |||
8548 | case CK_UncheckedDerivedToBase: { | |||
8549 | APValue DerivedObject; | |||
8550 | if (!Evaluate(DerivedObject, Info, E->getSubExpr())) | |||
8551 | return false; | |||
8552 | if (!DerivedObject.isStruct()) | |||
8553 | return Error(E->getSubExpr()); | |||
8554 | ||||
8555 | // Derived-to-base rvalue conversion: just slice off the derived part. | |||
8556 | APValue *Value = &DerivedObject; | |||
8557 | const CXXRecordDecl *RD = E->getSubExpr()->getType()->getAsCXXRecordDecl(); | |||
8558 | for (CastExpr::path_const_iterator PathI = E->path_begin(), | |||
8559 | PathE = E->path_end(); PathI != PathE; ++PathI) { | |||
8560 | assert(!(*PathI)->isVirtual() && "record rvalue with virtual base")((!(*PathI)->isVirtual() && "record rvalue with virtual base" ) ? static_cast<void> (0) : __assert_fail ("!(*PathI)->isVirtual() && \"record rvalue with virtual base\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8560, __PRETTY_FUNCTION__)); | |||
8561 | const CXXRecordDecl *Base = (*PathI)->getType()->getAsCXXRecordDecl(); | |||
8562 | Value = &Value->getStructBase(getBaseIndex(RD, Base)); | |||
8563 | RD = Base; | |||
8564 | } | |||
8565 | Result = *Value; | |||
8566 | return true; | |||
8567 | } | |||
8568 | } | |||
8569 | } | |||
8570 | ||||
8571 | bool RecordExprEvaluator::VisitInitListExpr(const InitListExpr *E) { | |||
8572 | if (E->isTransparent()) | |||
8573 | return Visit(E->getInit(0)); | |||
8574 | ||||
8575 | const RecordDecl *RD = E->getType()->castAs<RecordType>()->getDecl(); | |||
8576 | if (RD->isInvalidDecl()) return false; | |||
8577 | const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD); | |||
8578 | auto *CXXRD = dyn_cast<CXXRecordDecl>(RD); | |||
8579 | ||||
8580 | EvalInfo::EvaluatingConstructorRAII EvalObj( | |||
8581 | Info, | |||
8582 | ObjectUnderConstruction{This.getLValueBase(), This.Designator.Entries}, | |||
8583 | CXXRD && CXXRD->getNumBases()); | |||
8584 | ||||
8585 | if (RD->isUnion()) { | |||
8586 | const FieldDecl *Field = E->getInitializedFieldInUnion(); | |||
8587 | Result = APValue(Field); | |||
8588 | if (!Field) | |||
8589 | return true; | |||
8590 | ||||
8591 | // If the initializer list for a union does not contain any elements, the | |||
8592 | // first element of the union is value-initialized. | |||
8593 | // FIXME: The element should be initialized from an initializer list. | |||
8594 | // Is this difference ever observable for initializer lists which | |||
8595 | // we don't build? | |||
8596 | ImplicitValueInitExpr VIE(Field->getType()); | |||
8597 | const Expr *InitExpr = E->getNumInits() ? E->getInit(0) : &VIE; | |||
8598 | ||||
8599 | LValue Subobject = This; | |||
8600 | if (!HandleLValueMember(Info, InitExpr, Subobject, Field, &Layout)) | |||
8601 | return false; | |||
8602 | ||||
8603 | // Temporarily override This, in case there's a CXXDefaultInitExpr in here. | |||
8604 | ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This, | |||
8605 | isa<CXXDefaultInitExpr>(InitExpr)); | |||
8606 | ||||
8607 | return EvaluateInPlace(Result.getUnionValue(), Info, Subobject, InitExpr); | |||
8608 | } | |||
8609 | ||||
8610 | if (!Result.hasValue()) | |||
8611 | Result = APValue(APValue::UninitStruct(), CXXRD ? CXXRD->getNumBases() : 0, | |||
8612 | std::distance(RD->field_begin(), RD->field_end())); | |||
8613 | unsigned ElementNo = 0; | |||
8614 | bool Success = true; | |||
8615 | ||||
8616 | // Initialize base classes. | |||
8617 | if (CXXRD && CXXRD->getNumBases()) { | |||
8618 | for (const auto &Base : CXXRD->bases()) { | |||
8619 | assert(ElementNo < E->getNumInits() && "missing init for base class")((ElementNo < E->getNumInits() && "missing init for base class" ) ? static_cast<void> (0) : __assert_fail ("ElementNo < E->getNumInits() && \"missing init for base class\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8619, __PRETTY_FUNCTION__)); | |||
8620 | const Expr *Init = E->getInit(ElementNo); | |||
8621 | ||||
8622 | LValue Subobject = This; | |||
8623 | if (!HandleLValueBase(Info, Init, Subobject, CXXRD, &Base)) | |||
8624 | return false; | |||
8625 | ||||
8626 | APValue &FieldVal = Result.getStructBase(ElementNo); | |||
8627 | if (!EvaluateInPlace(FieldVal, Info, Subobject, Init)) { | |||
8628 | if (!Info.noteFailure()) | |||
8629 | return false; | |||
8630 | Success = false; | |||
8631 | } | |||
8632 | ++ElementNo; | |||
8633 | } | |||
8634 | ||||
8635 | EvalObj.finishedConstructingBases(); | |||
8636 | } | |||
8637 | ||||
8638 | // Initialize members. | |||
8639 | for (const auto *Field : RD->fields()) { | |||
8640 | // Anonymous bit-fields are not considered members of the class for | |||
8641 | // purposes of aggregate initialization. | |||
8642 | if (Field->isUnnamedBitfield()) | |||
8643 | continue; | |||
8644 | ||||
8645 | LValue Subobject = This; | |||
8646 | ||||
8647 | bool HaveInit = ElementNo < E->getNumInits(); | |||
8648 | ||||
8649 | // FIXME: Diagnostics here should point to the end of the initializer | |||
8650 | // list, not the start. | |||
8651 | if (!HandleLValueMember(Info, HaveInit ? E->getInit(ElementNo) : E, | |||
8652 | Subobject, Field, &Layout)) | |||
8653 | return false; | |||
8654 | ||||
8655 | // Perform an implicit value-initialization for members beyond the end of | |||
8656 | // the initializer list. | |||
8657 | ImplicitValueInitExpr VIE(HaveInit ? Info.Ctx.IntTy : Field->getType()); | |||
8658 | const Expr *Init = HaveInit ? E->getInit(ElementNo++) : &VIE; | |||
8659 | ||||
8660 | // Temporarily override This, in case there's a CXXDefaultInitExpr in here. | |||
8661 | ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This, | |||
8662 | isa<CXXDefaultInitExpr>(Init)); | |||
8663 | ||||
8664 | APValue &FieldVal = Result.getStructField(Field->getFieldIndex()); | |||
8665 | if (!EvaluateInPlace(FieldVal, Info, Subobject, Init) || | |||
8666 | (Field->isBitField() && !truncateBitfieldValue(Info, Init, | |||
8667 | FieldVal, Field))) { | |||
8668 | if (!Info.noteFailure()) | |||
8669 | return false; | |||
8670 | Success = false; | |||
8671 | } | |||
8672 | } | |||
8673 | ||||
8674 | return Success; | |||
8675 | } | |||
8676 | ||||
8677 | bool RecordExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E, | |||
8678 | QualType T) { | |||
8679 | // Note that E's type is not necessarily the type of our class here; we might | |||
8680 | // be initializing an array element instead. | |||
8681 | const CXXConstructorDecl *FD = E->getConstructor(); | |||
8682 | if (FD->isInvalidDecl() || FD->getParent()->isInvalidDecl()) return false; | |||
8683 | ||||
8684 | bool ZeroInit = E->requiresZeroInitialization(); | |||
8685 | if (CheckTrivialDefaultConstructor(Info, E->getExprLoc(), FD, ZeroInit)) { | |||
8686 | // If we've already performed zero-initialization, we're already done. | |||
8687 | if (Result.hasValue()) | |||
8688 | return true; | |||
8689 | ||||
8690 | if (ZeroInit) | |||
8691 | return ZeroInitialization(E, T); | |||
8692 | ||||
8693 | Result = getDefaultInitValue(T); | |||
8694 | return true; | |||
8695 | } | |||
8696 | ||||
8697 | const FunctionDecl *Definition = nullptr; | |||
8698 | auto Body = FD->getBody(Definition); | |||
8699 | ||||
8700 | if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body)) | |||
8701 | return false; | |||
8702 | ||||
8703 | // Avoid materializing a temporary for an elidable copy/move constructor. | |||
8704 | if (E->isElidable() && !ZeroInit) | |||
8705 | if (const MaterializeTemporaryExpr *ME | |||
8706 | = dyn_cast<MaterializeTemporaryExpr>(E->getArg(0))) | |||
8707 | return Visit(ME->GetTemporaryExpr()); | |||
8708 | ||||
8709 | if (ZeroInit && !ZeroInitialization(E, T)) | |||
8710 | return false; | |||
8711 | ||||
8712 | auto Args = llvm::makeArrayRef(E->getArgs(), E->getNumArgs()); | |||
8713 | return HandleConstructorCall(E, This, Args, | |||
8714 | cast<CXXConstructorDecl>(Definition), Info, | |||
8715 | Result); | |||
8716 | } | |||
8717 | ||||
8718 | bool RecordExprEvaluator::VisitCXXInheritedCtorInitExpr( | |||
8719 | const CXXInheritedCtorInitExpr *E) { | |||
8720 | if (!Info.CurrentCall) { | |||
8721 | assert(Info.checkingPotentialConstantExpression())((Info.checkingPotentialConstantExpression()) ? static_cast< void> (0) : __assert_fail ("Info.checkingPotentialConstantExpression()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8721, __PRETTY_FUNCTION__)); | |||
8722 | return false; | |||
8723 | } | |||
8724 | ||||
8725 | const CXXConstructorDecl *FD = E->getConstructor(); | |||
8726 | if (FD->isInvalidDecl() || FD->getParent()->isInvalidDecl()) | |||
8727 | return false; | |||
8728 | ||||
8729 | const FunctionDecl *Definition = nullptr; | |||
8730 | auto Body = FD->getBody(Definition); | |||
8731 | ||||
8732 | if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body)) | |||
8733 | return false; | |||
8734 | ||||
8735 | return HandleConstructorCall(E, This, Info.CurrentCall->Arguments, | |||
8736 | cast<CXXConstructorDecl>(Definition), Info, | |||
8737 | Result); | |||
8738 | } | |||
8739 | ||||
8740 | bool RecordExprEvaluator::VisitCXXStdInitializerListExpr( | |||
8741 | const CXXStdInitializerListExpr *E) { | |||
8742 | const ConstantArrayType *ArrayType = | |||
8743 | Info.Ctx.getAsConstantArrayType(E->getSubExpr()->getType()); | |||
8744 | ||||
8745 | LValue Array; | |||
8746 | if (!EvaluateLValue(E->getSubExpr(), Array, Info)) | |||
8747 | return false; | |||
8748 | ||||
8749 | // Get a pointer to the first element of the array. | |||
8750 | Array.addArray(Info, E, ArrayType); | |||
8751 | ||||
8752 | // FIXME: Perform the checks on the field types in SemaInit. | |||
8753 | RecordDecl *Record = E->getType()->castAs<RecordType>()->getDecl(); | |||
8754 | RecordDecl::field_iterator Field = Record->field_begin(); | |||
8755 | if (Field == Record->field_end()) | |||
8756 | return Error(E); | |||
8757 | ||||
8758 | // Start pointer. | |||
8759 | if (!Field->getType()->isPointerType() || | |||
8760 | !Info.Ctx.hasSameType(Field->getType()->getPointeeType(), | |||
8761 | ArrayType->getElementType())) | |||
8762 | return Error(E); | |||
8763 | ||||
8764 | // FIXME: What if the initializer_list type has base classes, etc? | |||
8765 | Result = APValue(APValue::UninitStruct(), 0, 2); | |||
8766 | Array.moveInto(Result.getStructField(0)); | |||
8767 | ||||
8768 | if (++Field == Record->field_end()) | |||
8769 | return Error(E); | |||
8770 | ||||
8771 | if (Field->getType()->isPointerType() && | |||
8772 | Info.Ctx.hasSameType(Field->getType()->getPointeeType(), | |||
8773 | ArrayType->getElementType())) { | |||
8774 | // End pointer. | |||
8775 | if (!HandleLValueArrayAdjustment(Info, E, Array, | |||
8776 | ArrayType->getElementType(), | |||
8777 | ArrayType->getSize().getZExtValue())) | |||
8778 | return false; | |||
8779 | Array.moveInto(Result.getStructField(1)); | |||
8780 | } else if (Info.Ctx.hasSameType(Field->getType(), Info.Ctx.getSizeType())) | |||
8781 | // Length. | |||
8782 | Result.getStructField(1) = APValue(APSInt(ArrayType->getSize())); | |||
8783 | else | |||
8784 | return Error(E); | |||
8785 | ||||
8786 | if (++Field != Record->field_end()) | |||
8787 | return Error(E); | |||
8788 | ||||
8789 | return true; | |||
8790 | } | |||
8791 | ||||
8792 | bool RecordExprEvaluator::VisitLambdaExpr(const LambdaExpr *E) { | |||
8793 | const CXXRecordDecl *ClosureClass = E->getLambdaClass(); | |||
8794 | if (ClosureClass->isInvalidDecl()) | |||
8795 | return false; | |||
8796 | ||||
8797 | const size_t NumFields = | |||
8798 | std::distance(ClosureClass->field_begin(), ClosureClass->field_end()); | |||
8799 | ||||
8800 | assert(NumFields == (size_t)std::distance(E->capture_init_begin(),((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") ? static_cast<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\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8803, __PRETTY_FUNCTION__)) | |||
8801 | E->capture_init_end()) &&((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") ? static_cast<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\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8803, __PRETTY_FUNCTION__)) | |||
8802 | "The number of lambda capture initializers should equal the number of "((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") ? static_cast<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\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8803, __PRETTY_FUNCTION__)) | |||
8803 | "fields within the closure type")((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") ? static_cast<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\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8803, __PRETTY_FUNCTION__)); | |||
8804 | ||||
8805 | Result = APValue(APValue::UninitStruct(), /*NumBases*/0, NumFields); | |||
8806 | // Iterate through all the lambda's closure object's fields and initialize | |||
8807 | // them. | |||
8808 | auto *CaptureInitIt = E->capture_init_begin(); | |||
8809 | const LambdaCapture *CaptureIt = ClosureClass->captures_begin(); | |||
8810 | bool Success = true; | |||
8811 | for (const auto *Field : ClosureClass->fields()) { | |||
8812 | assert(CaptureInitIt != E->capture_init_end())((CaptureInitIt != E->capture_init_end()) ? static_cast< void> (0) : __assert_fail ("CaptureInitIt != E->capture_init_end()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8812, __PRETTY_FUNCTION__)); | |||
8813 | // Get the initializer for this field | |||
8814 | Expr *const CurFieldInit = *CaptureInitIt++; | |||
8815 | ||||
8816 | // If there is no initializer, either this is a VLA or an error has | |||
8817 | // occurred. | |||
8818 | if (!CurFieldInit) | |||
8819 | return Error(E); | |||
8820 | ||||
8821 | APValue &FieldVal = Result.getStructField(Field->getFieldIndex()); | |||
8822 | if (!EvaluateInPlace(FieldVal, Info, This, CurFieldInit)) { | |||
8823 | if (!Info.keepEvaluatingAfterFailure()) | |||
8824 | return false; | |||
8825 | Success = false; | |||
8826 | } | |||
8827 | ++CaptureIt; | |||
8828 | } | |||
8829 | return Success; | |||
8830 | } | |||
8831 | ||||
8832 | static bool EvaluateRecord(const Expr *E, const LValue &This, | |||
8833 | APValue &Result, EvalInfo &Info) { | |||
8834 | assert(E->isRValue() && E->getType()->isRecordType() &&((E->isRValue() && E->getType()->isRecordType () && "can't evaluate expression as a record rvalue") ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isRecordType() && \"can't evaluate expression as a record rvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8835, __PRETTY_FUNCTION__)) | |||
8835 | "can't evaluate expression as a record rvalue")((E->isRValue() && E->getType()->isRecordType () && "can't evaluate expression as a record rvalue") ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isRecordType() && \"can't evaluate expression as a record rvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8835, __PRETTY_FUNCTION__)); | |||
8836 | return RecordExprEvaluator(Info, This, Result).Visit(E); | |||
8837 | } | |||
8838 | ||||
8839 | //===----------------------------------------------------------------------===// | |||
8840 | // Temporary Evaluation | |||
8841 | // | |||
8842 | // Temporaries are represented in the AST as rvalues, but generally behave like | |||
8843 | // lvalues. The full-object of which the temporary is a subobject is implicitly | |||
8844 | // materialized so that a reference can bind to it. | |||
8845 | //===----------------------------------------------------------------------===// | |||
8846 | namespace { | |||
8847 | class TemporaryExprEvaluator | |||
8848 | : public LValueExprEvaluatorBase<TemporaryExprEvaluator> { | |||
8849 | public: | |||
8850 | TemporaryExprEvaluator(EvalInfo &Info, LValue &Result) : | |||
8851 | LValueExprEvaluatorBaseTy(Info, Result, false) {} | |||
8852 | ||||
8853 | /// Visit an expression which constructs the value of this temporary. | |||
8854 | bool VisitConstructExpr(const Expr *E) { | |||
8855 | APValue &Value = | |||
8856 | Info.CurrentCall->createTemporary(E, E->getType(), false, Result); | |||
8857 | return EvaluateInPlace(Value, Info, Result, E); | |||
8858 | } | |||
8859 | ||||
8860 | bool VisitCastExpr(const CastExpr *E) { | |||
8861 | switch (E->getCastKind()) { | |||
8862 | default: | |||
8863 | return LValueExprEvaluatorBaseTy::VisitCastExpr(E); | |||
8864 | ||||
8865 | case CK_ConstructorConversion: | |||
8866 | return VisitConstructExpr(E->getSubExpr()); | |||
8867 | } | |||
8868 | } | |||
8869 | bool VisitInitListExpr(const InitListExpr *E) { | |||
8870 | return VisitConstructExpr(E); | |||
8871 | } | |||
8872 | bool VisitCXXConstructExpr(const CXXConstructExpr *E) { | |||
8873 | return VisitConstructExpr(E); | |||
8874 | } | |||
8875 | bool VisitCallExpr(const CallExpr *E) { | |||
8876 | return VisitConstructExpr(E); | |||
8877 | } | |||
8878 | bool VisitCXXStdInitializerListExpr(const CXXStdInitializerListExpr *E) { | |||
8879 | return VisitConstructExpr(E); | |||
8880 | } | |||
8881 | bool VisitLambdaExpr(const LambdaExpr *E) { | |||
8882 | return VisitConstructExpr(E); | |||
8883 | } | |||
8884 | }; | |||
8885 | } // end anonymous namespace | |||
8886 | ||||
8887 | /// Evaluate an expression of record type as a temporary. | |||
8888 | static bool EvaluateTemporary(const Expr *E, LValue &Result, EvalInfo &Info) { | |||
8889 | assert(E->isRValue() && E->getType()->isRecordType())((E->isRValue() && E->getType()->isRecordType ()) ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isRecordType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8889, __PRETTY_FUNCTION__)); | |||
8890 | return TemporaryExprEvaluator(Info, Result).Visit(E); | |||
8891 | } | |||
8892 | ||||
8893 | //===----------------------------------------------------------------------===// | |||
8894 | // Vector Evaluation | |||
8895 | //===----------------------------------------------------------------------===// | |||
8896 | ||||
8897 | namespace { | |||
8898 | class VectorExprEvaluator | |||
8899 | : public ExprEvaluatorBase<VectorExprEvaluator> { | |||
8900 | APValue &Result; | |||
8901 | public: | |||
8902 | ||||
8903 | VectorExprEvaluator(EvalInfo &info, APValue &Result) | |||
8904 | : ExprEvaluatorBaseTy(info), Result(Result) {} | |||
8905 | ||||
8906 | bool Success(ArrayRef<APValue> V, const Expr *E) { | |||
8907 | assert(V.size() == E->getType()->castAs<VectorType>()->getNumElements())((V.size() == E->getType()->castAs<VectorType>()-> getNumElements()) ? static_cast<void> (0) : __assert_fail ("V.size() == E->getType()->castAs<VectorType>()->getNumElements()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8907, __PRETTY_FUNCTION__)); | |||
8908 | // FIXME: remove this APValue copy. | |||
8909 | Result = APValue(V.data(), V.size()); | |||
8910 | return true; | |||
8911 | } | |||
8912 | bool Success(const APValue &V, const Expr *E) { | |||
8913 | assert(V.isVector())((V.isVector()) ? static_cast<void> (0) : __assert_fail ("V.isVector()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8913, __PRETTY_FUNCTION__)); | |||
8914 | Result = V; | |||
8915 | return true; | |||
8916 | } | |||
8917 | bool ZeroInitialization(const Expr *E); | |||
8918 | ||||
8919 | bool VisitUnaryReal(const UnaryOperator *E) | |||
8920 | { return Visit(E->getSubExpr()); } | |||
8921 | bool VisitCastExpr(const CastExpr* E); | |||
8922 | bool VisitInitListExpr(const InitListExpr *E); | |||
8923 | bool VisitUnaryImag(const UnaryOperator *E); | |||
8924 | // FIXME: Missing: unary -, unary ~, binary add/sub/mul/div, | |||
8925 | // binary comparisons, binary and/or/xor, | |||
8926 | // shufflevector, ExtVectorElementExpr | |||
8927 | }; | |||
8928 | } // end anonymous namespace | |||
8929 | ||||
8930 | static bool EvaluateVector(const Expr* E, APValue& Result, EvalInfo &Info) { | |||
8931 | assert(E->isRValue() && E->getType()->isVectorType() &&"not a vector rvalue")((E->isRValue() && E->getType()->isVectorType () &&"not a vector rvalue") ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isVectorType() &&\"not a vector rvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 8931, __PRETTY_FUNCTION__)); | |||
8932 | return VectorExprEvaluator(Info, Result).Visit(E); | |||
8933 | } | |||
8934 | ||||
8935 | bool VectorExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
8936 | const VectorType *VTy = E->getType()->castAs<VectorType>(); | |||
8937 | unsigned NElts = VTy->getNumElements(); | |||
8938 | ||||
8939 | const Expr *SE = E->getSubExpr(); | |||
8940 | QualType SETy = SE->getType(); | |||
8941 | ||||
8942 | switch (E->getCastKind()) { | |||
8943 | case CK_VectorSplat: { | |||
8944 | APValue Val = APValue(); | |||
8945 | if (SETy->isIntegerType()) { | |||
8946 | APSInt IntResult; | |||
8947 | if (!EvaluateInteger(SE, IntResult, Info)) | |||
8948 | return false; | |||
8949 | Val = APValue(std::move(IntResult)); | |||
8950 | } else if (SETy->isRealFloatingType()) { | |||
8951 | APFloat FloatResult(0.0); | |||
8952 | if (!EvaluateFloat(SE, FloatResult, Info)) | |||
8953 | return false; | |||
8954 | Val = APValue(std::move(FloatResult)); | |||
8955 | } else { | |||
8956 | return Error(E); | |||
8957 | } | |||
8958 | ||||
8959 | // Splat and create vector APValue. | |||
8960 | SmallVector<APValue, 4> Elts(NElts, Val); | |||
8961 | return Success(Elts, E); | |||
8962 | } | |||
8963 | case CK_BitCast: { | |||
8964 | // Evaluate the operand into an APInt we can extract from. | |||
8965 | llvm::APInt SValInt; | |||
8966 | if (!EvalAndBitcastToAPInt(Info, SE, SValInt)) | |||
8967 | return false; | |||
8968 | // Extract the elements | |||
8969 | QualType EltTy = VTy->getElementType(); | |||
8970 | unsigned EltSize = Info.Ctx.getTypeSize(EltTy); | |||
8971 | bool BigEndian = Info.Ctx.getTargetInfo().isBigEndian(); | |||
8972 | SmallVector<APValue, 4> Elts; | |||
8973 | if (EltTy->isRealFloatingType()) { | |||
8974 | const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(EltTy); | |||
8975 | unsigned FloatEltSize = EltSize; | |||
8976 | if (&Sem == &APFloat::x87DoubleExtended()) | |||
8977 | FloatEltSize = 80; | |||
8978 | for (unsigned i = 0; i < NElts; i++) { | |||
8979 | llvm::APInt Elt; | |||
8980 | if (BigEndian) | |||
8981 | Elt = SValInt.rotl(i*EltSize+FloatEltSize).trunc(FloatEltSize); | |||
8982 | else | |||
8983 | Elt = SValInt.rotr(i*EltSize).trunc(FloatEltSize); | |||
8984 | Elts.push_back(APValue(APFloat(Sem, Elt))); | |||
8985 | } | |||
8986 | } else if (EltTy->isIntegerType()) { | |||
8987 | for (unsigned i = 0; i < NElts; i++) { | |||
8988 | llvm::APInt Elt; | |||
8989 | if (BigEndian) | |||
8990 | Elt = SValInt.rotl(i*EltSize+EltSize).zextOrTrunc(EltSize); | |||
8991 | else | |||
8992 | Elt = SValInt.rotr(i*EltSize).zextOrTrunc(EltSize); | |||
8993 | Elts.push_back(APValue(APSInt(Elt, EltTy->isSignedIntegerType()))); | |||
8994 | } | |||
8995 | } else { | |||
8996 | return Error(E); | |||
8997 | } | |||
8998 | return Success(Elts, E); | |||
8999 | } | |||
9000 | default: | |||
9001 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
9002 | } | |||
9003 | } | |||
9004 | ||||
9005 | bool | |||
9006 | VectorExprEvaluator::VisitInitListExpr(const InitListExpr *E) { | |||
9007 | const VectorType *VT = E->getType()->castAs<VectorType>(); | |||
9008 | unsigned NumInits = E->getNumInits(); | |||
9009 | unsigned NumElements = VT->getNumElements(); | |||
9010 | ||||
9011 | QualType EltTy = VT->getElementType(); | |||
9012 | SmallVector<APValue, 4> Elements; | |||
9013 | ||||
9014 | // The number of initializers can be less than the number of | |||
9015 | // vector elements. For OpenCL, this can be due to nested vector | |||
9016 | // initialization. For GCC compatibility, missing trailing elements | |||
9017 | // should be initialized with zeroes. | |||
9018 | unsigned CountInits = 0, CountElts = 0; | |||
9019 | while (CountElts < NumElements) { | |||
9020 | // Handle nested vector initialization. | |||
9021 | if (CountInits < NumInits | |||
9022 | && E->getInit(CountInits)->getType()->isVectorType()) { | |||
9023 | APValue v; | |||
9024 | if (!EvaluateVector(E->getInit(CountInits), v, Info)) | |||
9025 | return Error(E); | |||
9026 | unsigned vlen = v.getVectorLength(); | |||
9027 | for (unsigned j = 0; j < vlen; j++) | |||
9028 | Elements.push_back(v.getVectorElt(j)); | |||
9029 | CountElts += vlen; | |||
9030 | } else if (EltTy->isIntegerType()) { | |||
9031 | llvm::APSInt sInt(32); | |||
9032 | if (CountInits < NumInits) { | |||
9033 | if (!EvaluateInteger(E->getInit(CountInits), sInt, Info)) | |||
9034 | return false; | |||
9035 | } else // trailing integer zero. | |||
9036 | sInt = Info.Ctx.MakeIntValue(0, EltTy); | |||
9037 | Elements.push_back(APValue(sInt)); | |||
9038 | CountElts++; | |||
9039 | } else { | |||
9040 | llvm::APFloat f(0.0); | |||
9041 | if (CountInits < NumInits) { | |||
9042 | if (!EvaluateFloat(E->getInit(CountInits), f, Info)) | |||
9043 | return false; | |||
9044 | } else // trailing float zero. | |||
9045 | f = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy)); | |||
9046 | Elements.push_back(APValue(f)); | |||
9047 | CountElts++; | |||
9048 | } | |||
9049 | CountInits++; | |||
9050 | } | |||
9051 | return Success(Elements, E); | |||
9052 | } | |||
9053 | ||||
9054 | bool | |||
9055 | VectorExprEvaluator::ZeroInitialization(const Expr *E) { | |||
9056 | const VectorType *VT = E->getType()->getAs<VectorType>(); | |||
9057 | QualType EltTy = VT->getElementType(); | |||
9058 | APValue ZeroElement; | |||
9059 | if (EltTy->isIntegerType()) | |||
9060 | ZeroElement = APValue(Info.Ctx.MakeIntValue(0, EltTy)); | |||
9061 | else | |||
9062 | ZeroElement = | |||
9063 | APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy))); | |||
9064 | ||||
9065 | SmallVector<APValue, 4> Elements(VT->getNumElements(), ZeroElement); | |||
9066 | return Success(Elements, E); | |||
9067 | } | |||
9068 | ||||
9069 | bool VectorExprEvaluator::VisitUnaryImag(const UnaryOperator *E) { | |||
9070 | VisitIgnoredValue(E->getSubExpr()); | |||
9071 | return ZeroInitialization(E); | |||
9072 | } | |||
9073 | ||||
9074 | //===----------------------------------------------------------------------===// | |||
9075 | // Array Evaluation | |||
9076 | //===----------------------------------------------------------------------===// | |||
9077 | ||||
9078 | namespace { | |||
9079 | class ArrayExprEvaluator | |||
9080 | : public ExprEvaluatorBase<ArrayExprEvaluator> { | |||
9081 | const LValue &This; | |||
9082 | APValue &Result; | |||
9083 | public: | |||
9084 | ||||
9085 | ArrayExprEvaluator(EvalInfo &Info, const LValue &This, APValue &Result) | |||
9086 | : ExprEvaluatorBaseTy(Info), This(This), Result(Result) {} | |||
9087 | ||||
9088 | bool Success(const APValue &V, const Expr *E) { | |||
9089 | assert(V.isArray() && "expected array")((V.isArray() && "expected array") ? static_cast<void > (0) : __assert_fail ("V.isArray() && \"expected array\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9089, __PRETTY_FUNCTION__)); | |||
9090 | Result = V; | |||
9091 | return true; | |||
9092 | } | |||
9093 | ||||
9094 | bool ZeroInitialization(const Expr *E) { | |||
9095 | const ConstantArrayType *CAT = | |||
9096 | Info.Ctx.getAsConstantArrayType(E->getType()); | |||
9097 | if (!CAT) | |||
9098 | return Error(E); | |||
9099 | ||||
9100 | Result = APValue(APValue::UninitArray(), 0, | |||
9101 | CAT->getSize().getZExtValue()); | |||
9102 | if (!Result.hasArrayFiller()) return true; | |||
9103 | ||||
9104 | // Zero-initialize all elements. | |||
9105 | LValue Subobject = This; | |||
9106 | Subobject.addArray(Info, E, CAT); | |||
9107 | ImplicitValueInitExpr VIE(CAT->getElementType()); | |||
9108 | return EvaluateInPlace(Result.getArrayFiller(), Info, Subobject, &VIE); | |||
9109 | } | |||
9110 | ||||
9111 | bool VisitCallExpr(const CallExpr *E) { | |||
9112 | return handleCallExpr(E, Result, &This); | |||
9113 | } | |||
9114 | bool VisitInitListExpr(const InitListExpr *E, | |||
9115 | QualType AllocType = QualType()); | |||
9116 | bool VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E); | |||
9117 | bool VisitCXXConstructExpr(const CXXConstructExpr *E); | |||
9118 | bool VisitCXXConstructExpr(const CXXConstructExpr *E, | |||
9119 | const LValue &Subobject, | |||
9120 | APValue *Value, QualType Type); | |||
9121 | bool VisitStringLiteral(const StringLiteral *E, | |||
9122 | QualType AllocType = QualType()) { | |||
9123 | expandStringLiteral(Info, E, Result, AllocType); | |||
9124 | return true; | |||
9125 | } | |||
9126 | }; | |||
9127 | } // end anonymous namespace | |||
9128 | ||||
9129 | static bool EvaluateArray(const Expr *E, const LValue &This, | |||
9130 | APValue &Result, EvalInfo &Info) { | |||
9131 | assert(E->isRValue() && E->getType()->isArrayType() && "not an array rvalue")((E->isRValue() && E->getType()->isArrayType () && "not an array rvalue") ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isArrayType() && \"not an array rvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9131, __PRETTY_FUNCTION__)); | |||
9132 | return ArrayExprEvaluator(Info, This, Result).Visit(E); | |||
9133 | } | |||
9134 | ||||
9135 | static bool EvaluateArrayNewInitList(EvalInfo &Info, LValue &This, | |||
9136 | APValue &Result, const InitListExpr *ILE, | |||
9137 | QualType AllocType) { | |||
9138 | assert(ILE->isRValue() && ILE->getType()->isArrayType() &&((ILE->isRValue() && ILE->getType()->isArrayType () && "not an array rvalue") ? static_cast<void> (0) : __assert_fail ("ILE->isRValue() && ILE->getType()->isArrayType() && \"not an array rvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9139, __PRETTY_FUNCTION__)) | |||
9139 | "not an array rvalue")((ILE->isRValue() && ILE->getType()->isArrayType () && "not an array rvalue") ? static_cast<void> (0) : __assert_fail ("ILE->isRValue() && ILE->getType()->isArrayType() && \"not an array rvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9139, __PRETTY_FUNCTION__)); | |||
9140 | return ArrayExprEvaluator(Info, This, Result) | |||
9141 | .VisitInitListExpr(ILE, AllocType); | |||
9142 | } | |||
9143 | ||||
9144 | // Return true iff the given array filler may depend on the element index. | |||
9145 | static bool MaybeElementDependentArrayFiller(const Expr *FillerExpr) { | |||
9146 | // For now, just whitelist non-class value-initialization and initialization | |||
9147 | // lists comprised of them. | |||
9148 | if (isa<ImplicitValueInitExpr>(FillerExpr)) | |||
9149 | return false; | |||
9150 | if (const InitListExpr *ILE = dyn_cast<InitListExpr>(FillerExpr)) { | |||
9151 | for (unsigned I = 0, E = ILE->getNumInits(); I != E; ++I) { | |||
9152 | if (MaybeElementDependentArrayFiller(ILE->getInit(I))) | |||
9153 | return true; | |||
9154 | } | |||
9155 | return false; | |||
9156 | } | |||
9157 | return true; | |||
9158 | } | |||
9159 | ||||
9160 | bool ArrayExprEvaluator::VisitInitListExpr(const InitListExpr *E, | |||
9161 | QualType AllocType) { | |||
9162 | const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType( | |||
9163 | AllocType.isNull() ? E->getType() : AllocType); | |||
9164 | if (!CAT) | |||
9165 | return Error(E); | |||
9166 | ||||
9167 | // C++11 [dcl.init.string]p1: A char array [...] can be initialized by [...] | |||
9168 | // an appropriately-typed string literal enclosed in braces. | |||
9169 | if (E->isStringLiteralInit()) { | |||
9170 | auto *SL = dyn_cast<StringLiteral>(E->getInit(0)->IgnoreParens()); | |||
9171 | // FIXME: Support ObjCEncodeExpr here once we support it in | |||
9172 | // ArrayExprEvaluator generally. | |||
9173 | if (!SL) | |||
9174 | return Error(E); | |||
9175 | return VisitStringLiteral(SL, AllocType); | |||
9176 | } | |||
9177 | ||||
9178 | bool Success = true; | |||
9179 | ||||
9180 | assert((!Result.isArray() || Result.getArrayInitializedElts() == 0) &&(((!Result.isArray() || Result.getArrayInitializedElts() == 0 ) && "zero-initialized array shouldn't have any initialized elts" ) ? static_cast<void> (0) : __assert_fail ("(!Result.isArray() || Result.getArrayInitializedElts() == 0) && \"zero-initialized array shouldn't have any initialized elts\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9181, __PRETTY_FUNCTION__)) | |||
9181 | "zero-initialized array shouldn't have any initialized elts")(((!Result.isArray() || Result.getArrayInitializedElts() == 0 ) && "zero-initialized array shouldn't have any initialized elts" ) ? static_cast<void> (0) : __assert_fail ("(!Result.isArray() || Result.getArrayInitializedElts() == 0) && \"zero-initialized array shouldn't have any initialized elts\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9181, __PRETTY_FUNCTION__)); | |||
9182 | APValue Filler; | |||
9183 | if (Result.isArray() && Result.hasArrayFiller()) | |||
9184 | Filler = Result.getArrayFiller(); | |||
9185 | ||||
9186 | unsigned NumEltsToInit = E->getNumInits(); | |||
9187 | unsigned NumElts = CAT->getSize().getZExtValue(); | |||
9188 | const Expr *FillerExpr = E->hasArrayFiller() ? E->getArrayFiller() : nullptr; | |||
9189 | ||||
9190 | // If the initializer might depend on the array index, run it for each | |||
9191 | // array element. | |||
9192 | if (NumEltsToInit != NumElts && MaybeElementDependentArrayFiller(FillerExpr)) | |||
9193 | NumEltsToInit = NumElts; | |||
9194 | ||||
9195 | 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) | |||
9196 | << NumEltsToInit << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("exprconstant")) { llvm::dbgs() << "The number of elements to initialize: " << NumEltsToInit << ".\n"; } } while (false); | |||
9197 | ||||
9198 | Result = APValue(APValue::UninitArray(), NumEltsToInit, NumElts); | |||
9199 | ||||
9200 | // If the array was previously zero-initialized, preserve the | |||
9201 | // zero-initialized values. | |||
9202 | if (Filler.hasValue()) { | |||
9203 | for (unsigned I = 0, E = Result.getArrayInitializedElts(); I != E; ++I) | |||
9204 | Result.getArrayInitializedElt(I) = Filler; | |||
9205 | if (Result.hasArrayFiller()) | |||
9206 | Result.getArrayFiller() = Filler; | |||
9207 | } | |||
9208 | ||||
9209 | LValue Subobject = This; | |||
9210 | Subobject.addArray(Info, E, CAT); | |||
9211 | for (unsigned Index = 0; Index != NumEltsToInit; ++Index) { | |||
9212 | const Expr *Init = | |||
9213 | Index < E->getNumInits() ? E->getInit(Index) : FillerExpr; | |||
9214 | if (!EvaluateInPlace(Result.getArrayInitializedElt(Index), | |||
9215 | Info, Subobject, Init) || | |||
9216 | !HandleLValueArrayAdjustment(Info, Init, Subobject, | |||
9217 | CAT->getElementType(), 1)) { | |||
9218 | if (!Info.noteFailure()) | |||
9219 | return false; | |||
9220 | Success = false; | |||
9221 | } | |||
9222 | } | |||
9223 | ||||
9224 | if (!Result.hasArrayFiller()) | |||
9225 | return Success; | |||
9226 | ||||
9227 | // If we get here, we have a trivial filler, which we can just evaluate | |||
9228 | // once and splat over the rest of the array elements. | |||
9229 | assert(FillerExpr && "no array filler for incomplete init list")((FillerExpr && "no array filler for incomplete init list" ) ? static_cast<void> (0) : __assert_fail ("FillerExpr && \"no array filler for incomplete init list\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9229, __PRETTY_FUNCTION__)); | |||
9230 | return EvaluateInPlace(Result.getArrayFiller(), Info, Subobject, | |||
9231 | FillerExpr) && Success; | |||
9232 | } | |||
9233 | ||||
9234 | bool ArrayExprEvaluator::VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E) { | |||
9235 | LValue CommonLV; | |||
9236 | if (E->getCommonExpr() && | |||
9237 | !Evaluate(Info.CurrentCall->createTemporary( | |||
9238 | E->getCommonExpr(), | |||
9239 | getStorageType(Info.Ctx, E->getCommonExpr()), false, | |||
9240 | CommonLV), | |||
9241 | Info, E->getCommonExpr()->getSourceExpr())) | |||
9242 | return false; | |||
9243 | ||||
9244 | auto *CAT = cast<ConstantArrayType>(E->getType()->castAsArrayTypeUnsafe()); | |||
9245 | ||||
9246 | uint64_t Elements = CAT->getSize().getZExtValue(); | |||
9247 | Result = APValue(APValue::UninitArray(), Elements, Elements); | |||
9248 | ||||
9249 | LValue Subobject = This; | |||
9250 | Subobject.addArray(Info, E, CAT); | |||
9251 | ||||
9252 | bool Success = true; | |||
9253 | for (EvalInfo::ArrayInitLoopIndex Index(Info); Index != Elements; ++Index) { | |||
9254 | if (!EvaluateInPlace(Result.getArrayInitializedElt(Index), | |||
9255 | Info, Subobject, E->getSubExpr()) || | |||
9256 | !HandleLValueArrayAdjustment(Info, E, Subobject, | |||
9257 | CAT->getElementType(), 1)) { | |||
9258 | if (!Info.noteFailure()) | |||
9259 | return false; | |||
9260 | Success = false; | |||
9261 | } | |||
9262 | } | |||
9263 | ||||
9264 | return Success; | |||
9265 | } | |||
9266 | ||||
9267 | bool ArrayExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E) { | |||
9268 | return VisitCXXConstructExpr(E, This, &Result, E->getType()); | |||
9269 | } | |||
9270 | ||||
9271 | bool ArrayExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E, | |||
9272 | const LValue &Subobject, | |||
9273 | APValue *Value, | |||
9274 | QualType Type) { | |||
9275 | bool HadZeroInit = Value->hasValue(); | |||
9276 | ||||
9277 | if (const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(Type)) { | |||
9278 | unsigned N = CAT->getSize().getZExtValue(); | |||
9279 | ||||
9280 | // Preserve the array filler if we had prior zero-initialization. | |||
9281 | APValue Filler = | |||
9282 | HadZeroInit && Value->hasArrayFiller() ? Value->getArrayFiller() | |||
9283 | : APValue(); | |||
9284 | ||||
9285 | *Value = APValue(APValue::UninitArray(), N, N); | |||
9286 | ||||
9287 | if (HadZeroInit) | |||
9288 | for (unsigned I = 0; I != N; ++I) | |||
9289 | Value->getArrayInitializedElt(I) = Filler; | |||
9290 | ||||
9291 | // Initialize the elements. | |||
9292 | LValue ArrayElt = Subobject; | |||
9293 | ArrayElt.addArray(Info, E, CAT); | |||
9294 | for (unsigned I = 0; I != N; ++I) | |||
9295 | if (!VisitCXXConstructExpr(E, ArrayElt, &Value->getArrayInitializedElt(I), | |||
9296 | CAT->getElementType()) || | |||
9297 | !HandleLValueArrayAdjustment(Info, E, ArrayElt, | |||
9298 | CAT->getElementType(), 1)) | |||
9299 | return false; | |||
9300 | ||||
9301 | return true; | |||
9302 | } | |||
9303 | ||||
9304 | if (!Type->isRecordType()) | |||
9305 | return Error(E); | |||
9306 | ||||
9307 | return RecordExprEvaluator(Info, Subobject, *Value) | |||
9308 | .VisitCXXConstructExpr(E, Type); | |||
9309 | } | |||
9310 | ||||
9311 | //===----------------------------------------------------------------------===// | |||
9312 | // Integer Evaluation | |||
9313 | // | |||
9314 | // As a GNU extension, we support casting pointers to sufficiently-wide integer | |||
9315 | // types and back in constant folding. Integer values are thus represented | |||
9316 | // either as an integer-valued APValue, or as an lvalue-valued APValue. | |||
9317 | //===----------------------------------------------------------------------===// | |||
9318 | ||||
9319 | namespace { | |||
9320 | class IntExprEvaluator | |||
9321 | : public ExprEvaluatorBase<IntExprEvaluator> { | |||
9322 | APValue &Result; | |||
9323 | public: | |||
9324 | IntExprEvaluator(EvalInfo &info, APValue &result) | |||
9325 | : ExprEvaluatorBaseTy(info), Result(result) {} | |||
9326 | ||||
9327 | bool Success(const llvm::APSInt &SI, const Expr *E, APValue &Result) { | |||
9328 | assert(E->getType()->isIntegralOrEnumerationType() &&((E->getType()->isIntegralOrEnumerationType() && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9329, __PRETTY_FUNCTION__)) | |||
9329 | "Invalid evaluation result.")((E->getType()->isIntegralOrEnumerationType() && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9329, __PRETTY_FUNCTION__)); | |||
9330 | assert(SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() &&((SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType () && "Invalid evaluation result.") ? static_cast< void> (0) : __assert_fail ("SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9331, __PRETTY_FUNCTION__)) | |||
9331 | "Invalid evaluation result.")((SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType () && "Invalid evaluation result.") ? static_cast< void> (0) : __assert_fail ("SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9331, __PRETTY_FUNCTION__)); | |||
9332 | assert(SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&((SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9333, __PRETTY_FUNCTION__)) | |||
9333 | "Invalid evaluation result.")((SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9333, __PRETTY_FUNCTION__)); | |||
9334 | Result = APValue(SI); | |||
9335 | return true; | |||
9336 | } | |||
9337 | bool Success(const llvm::APSInt &SI, const Expr *E) { | |||
9338 | return Success(SI, E, Result); | |||
9339 | } | |||
9340 | ||||
9341 | bool Success(const llvm::APInt &I, const Expr *E, APValue &Result) { | |||
9342 | assert(E->getType()->isIntegralOrEnumerationType() &&((E->getType()->isIntegralOrEnumerationType() && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9343, __PRETTY_FUNCTION__)) | |||
9343 | "Invalid evaluation result.")((E->getType()->isIntegralOrEnumerationType() && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9343, __PRETTY_FUNCTION__)); | |||
9344 | assert(I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&((I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9345, __PRETTY_FUNCTION__)) | |||
9345 | "Invalid evaluation result.")((I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9345, __PRETTY_FUNCTION__)); | |||
9346 | Result = APValue(APSInt(I)); | |||
9347 | Result.getInt().setIsUnsigned( | |||
9348 | E->getType()->isUnsignedIntegerOrEnumerationType()); | |||
9349 | return true; | |||
9350 | } | |||
9351 | bool Success(const llvm::APInt &I, const Expr *E) { | |||
9352 | return Success(I, E, Result); | |||
9353 | } | |||
9354 | ||||
9355 | bool Success(uint64_t Value, const Expr *E, APValue &Result) { | |||
9356 | assert(E->getType()->isIntegralOrEnumerationType() &&((E->getType()->isIntegralOrEnumerationType() && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9357, __PRETTY_FUNCTION__)) | |||
9357 | "Invalid evaluation result.")((E->getType()->isIntegralOrEnumerationType() && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9357, __PRETTY_FUNCTION__)); | |||
9358 | Result = APValue(Info.Ctx.MakeIntValue(Value, E->getType())); | |||
9359 | return true; | |||
9360 | } | |||
9361 | bool Success(uint64_t Value, const Expr *E) { | |||
9362 | return Success(Value, E, Result); | |||
9363 | } | |||
9364 | ||||
9365 | bool Success(CharUnits Size, const Expr *E) { | |||
9366 | return Success(Size.getQuantity(), E); | |||
9367 | } | |||
9368 | ||||
9369 | bool Success(const APValue &V, const Expr *E) { | |||
9370 | if (V.isLValue() || V.isAddrLabelDiff() || V.isIndeterminate()) { | |||
9371 | Result = V; | |||
9372 | return true; | |||
9373 | } | |||
9374 | return Success(V.getInt(), E); | |||
9375 | } | |||
9376 | ||||
9377 | bool ZeroInitialization(const Expr *E) { return Success(0, E); } | |||
9378 | ||||
9379 | //===--------------------------------------------------------------------===// | |||
9380 | // Visitor Methods | |||
9381 | //===--------------------------------------------------------------------===// | |||
9382 | ||||
9383 | bool VisitConstantExpr(const ConstantExpr *E); | |||
9384 | ||||
9385 | bool VisitIntegerLiteral(const IntegerLiteral *E) { | |||
9386 | return Success(E->getValue(), E); | |||
9387 | } | |||
9388 | bool VisitCharacterLiteral(const CharacterLiteral *E) { | |||
9389 | return Success(E->getValue(), E); | |||
9390 | } | |||
9391 | ||||
9392 | bool CheckReferencedDecl(const Expr *E, const Decl *D); | |||
9393 | bool VisitDeclRefExpr(const DeclRefExpr *E) { | |||
9394 | if (CheckReferencedDecl(E, E->getDecl())) | |||
9395 | return true; | |||
9396 | ||||
9397 | return ExprEvaluatorBaseTy::VisitDeclRefExpr(E); | |||
9398 | } | |||
9399 | bool VisitMemberExpr(const MemberExpr *E) { | |||
9400 | if (CheckReferencedDecl(E, E->getMemberDecl())) { | |||
9401 | VisitIgnoredBaseExpression(E->getBase()); | |||
9402 | return true; | |||
9403 | } | |||
9404 | ||||
9405 | return ExprEvaluatorBaseTy::VisitMemberExpr(E); | |||
9406 | } | |||
9407 | ||||
9408 | bool VisitCallExpr(const CallExpr *E); | |||
9409 | bool VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp); | |||
9410 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
9411 | bool VisitOffsetOfExpr(const OffsetOfExpr *E); | |||
9412 | bool VisitUnaryOperator(const UnaryOperator *E); | |||
9413 | ||||
9414 | bool VisitCastExpr(const CastExpr* E); | |||
9415 | bool VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E); | |||
9416 | ||||
9417 | bool VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { | |||
9418 | return Success(E->getValue(), E); | |||
9419 | } | |||
9420 | ||||
9421 | bool VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *E) { | |||
9422 | return Success(E->getValue(), E); | |||
9423 | } | |||
9424 | ||||
9425 | bool VisitArrayInitIndexExpr(const ArrayInitIndexExpr *E) { | |||
9426 | if (Info.ArrayInitIndex == uint64_t(-1)) { | |||
9427 | // We were asked to evaluate this subexpression independent of the | |||
9428 | // enclosing ArrayInitLoopExpr. We can't do that. | |||
9429 | Info.FFDiag(E); | |||
9430 | return false; | |||
9431 | } | |||
9432 | return Success(Info.ArrayInitIndex, E); | |||
9433 | } | |||
9434 | ||||
9435 | // Note, GNU defines __null as an integer, not a pointer. | |||
9436 | bool VisitGNUNullExpr(const GNUNullExpr *E) { | |||
9437 | return ZeroInitialization(E); | |||
9438 | } | |||
9439 | ||||
9440 | bool VisitTypeTraitExpr(const TypeTraitExpr *E) { | |||
9441 | return Success(E->getValue(), E); | |||
9442 | } | |||
9443 | ||||
9444 | bool VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) { | |||
9445 | return Success(E->getValue(), E); | |||
9446 | } | |||
9447 | ||||
9448 | bool VisitExpressionTraitExpr(const ExpressionTraitExpr *E) { | |||
9449 | return Success(E->getValue(), E); | |||
9450 | } | |||
9451 | ||||
9452 | bool VisitUnaryReal(const UnaryOperator *E); | |||
9453 | bool VisitUnaryImag(const UnaryOperator *E); | |||
9454 | ||||
9455 | bool VisitCXXNoexceptExpr(const CXXNoexceptExpr *E); | |||
9456 | bool VisitSizeOfPackExpr(const SizeOfPackExpr *E); | |||
9457 | bool VisitSourceLocExpr(const SourceLocExpr *E); | |||
9458 | // FIXME: Missing: array subscript of vector, member of vector | |||
9459 | }; | |||
9460 | ||||
9461 | class FixedPointExprEvaluator | |||
9462 | : public ExprEvaluatorBase<FixedPointExprEvaluator> { | |||
9463 | APValue &Result; | |||
9464 | ||||
9465 | public: | |||
9466 | FixedPointExprEvaluator(EvalInfo &info, APValue &result) | |||
9467 | : ExprEvaluatorBaseTy(info), Result(result) {} | |||
9468 | ||||
9469 | bool Success(const llvm::APInt &I, const Expr *E) { | |||
9470 | return Success( | |||
9471 | APFixedPoint(I, Info.Ctx.getFixedPointSemantics(E->getType())), E); | |||
9472 | } | |||
9473 | ||||
9474 | bool Success(uint64_t Value, const Expr *E) { | |||
9475 | return Success( | |||
9476 | APFixedPoint(Value, Info.Ctx.getFixedPointSemantics(E->getType())), E); | |||
9477 | } | |||
9478 | ||||
9479 | bool Success(const APValue &V, const Expr *E) { | |||
9480 | return Success(V.getFixedPoint(), E); | |||
9481 | } | |||
9482 | ||||
9483 | bool Success(const APFixedPoint &V, const Expr *E) { | |||
9484 | assert(E->getType()->isFixedPointType() && "Invalid evaluation result.")((E->getType()->isFixedPointType() && "Invalid evaluation result." ) ? static_cast<void> (0) : __assert_fail ("E->getType()->isFixedPointType() && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9484, __PRETTY_FUNCTION__)); | |||
9485 | assert(V.getWidth() == Info.Ctx.getIntWidth(E->getType()) &&((V.getWidth() == Info.Ctx.getIntWidth(E->getType()) && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("V.getWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9486, __PRETTY_FUNCTION__)) | |||
9486 | "Invalid evaluation result.")((V.getWidth() == Info.Ctx.getIntWidth(E->getType()) && "Invalid evaluation result.") ? static_cast<void> (0) : __assert_fail ("V.getWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9486, __PRETTY_FUNCTION__)); | |||
9487 | Result = APValue(V); | |||
9488 | return true; | |||
9489 | } | |||
9490 | ||||
9491 | //===--------------------------------------------------------------------===// | |||
9492 | // Visitor Methods | |||
9493 | //===--------------------------------------------------------------------===// | |||
9494 | ||||
9495 | bool VisitFixedPointLiteral(const FixedPointLiteral *E) { | |||
9496 | return Success(E->getValue(), E); | |||
9497 | } | |||
9498 | ||||
9499 | bool VisitCastExpr(const CastExpr *E); | |||
9500 | bool VisitUnaryOperator(const UnaryOperator *E); | |||
9501 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
9502 | }; | |||
9503 | } // end anonymous namespace | |||
9504 | ||||
9505 | /// EvaluateIntegerOrLValue - Evaluate an rvalue integral-typed expression, and | |||
9506 | /// produce either the integer value or a pointer. | |||
9507 | /// | |||
9508 | /// GCC has a heinous extension which folds casts between pointer types and | |||
9509 | /// pointer-sized integral types. We support this by allowing the evaluation of | |||
9510 | /// an integer rvalue to produce a pointer (represented as an lvalue) instead. | |||
9511 | /// Some simple arithmetic on such values is supported (they are treated much | |||
9512 | /// like char*). | |||
9513 | static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result, | |||
9514 | EvalInfo &Info) { | |||
9515 | assert(E->isRValue() && E->getType()->isIntegralOrEnumerationType())((E->isRValue() && E->getType()->isIntegralOrEnumerationType ()) ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isIntegralOrEnumerationType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9515, __PRETTY_FUNCTION__)); | |||
9516 | return IntExprEvaluator(Info, Result).Visit(E); | |||
9517 | } | |||
9518 | ||||
9519 | static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info) { | |||
9520 | APValue Val; | |||
9521 | if (!EvaluateIntegerOrLValue(E, Val, Info)) | |||
9522 | return false; | |||
9523 | if (!Val.isInt()) { | |||
9524 | // FIXME: It would be better to produce the diagnostic for casting | |||
9525 | // a pointer to an integer. | |||
9526 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
9527 | return false; | |||
9528 | } | |||
9529 | Result = Val.getInt(); | |||
9530 | return true; | |||
9531 | } | |||
9532 | ||||
9533 | bool IntExprEvaluator::VisitSourceLocExpr(const SourceLocExpr *E) { | |||
9534 | APValue Evaluated = E->EvaluateInContext( | |||
9535 | Info.Ctx, Info.CurrentCall->CurSourceLocExprScope.getDefaultExpr()); | |||
9536 | return Success(Evaluated, E); | |||
9537 | } | |||
9538 | ||||
9539 | static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result, | |||
9540 | EvalInfo &Info) { | |||
9541 | if (E->getType()->isFixedPointType()) { | |||
9542 | APValue Val; | |||
9543 | if (!FixedPointExprEvaluator(Info, Val).Visit(E)) | |||
9544 | return false; | |||
9545 | if (!Val.isFixedPoint()) | |||
9546 | return false; | |||
9547 | ||||
9548 | Result = Val.getFixedPoint(); | |||
9549 | return true; | |||
9550 | } | |||
9551 | return false; | |||
9552 | } | |||
9553 | ||||
9554 | static bool EvaluateFixedPointOrInteger(const Expr *E, APFixedPoint &Result, | |||
9555 | EvalInfo &Info) { | |||
9556 | if (E->getType()->isIntegerType()) { | |||
9557 | auto FXSema = Info.Ctx.getFixedPointSemantics(E->getType()); | |||
9558 | APSInt Val; | |||
9559 | if (!EvaluateInteger(E, Val, Info)) | |||
9560 | return false; | |||
9561 | Result = APFixedPoint(Val, FXSema); | |||
9562 | return true; | |||
9563 | } else if (E->getType()->isFixedPointType()) { | |||
9564 | return EvaluateFixedPoint(E, Result, Info); | |||
9565 | } | |||
9566 | return false; | |||
9567 | } | |||
9568 | ||||
9569 | /// Check whether the given declaration can be directly converted to an integral | |||
9570 | /// rvalue. If not, no diagnostic is produced; there are other things we can | |||
9571 | /// try. | |||
9572 | bool IntExprEvaluator::CheckReferencedDecl(const Expr* E, const Decl* D) { | |||
9573 | // Enums are integer constant exprs. | |||
9574 | if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D)) { | |||
9575 | // Check for signedness/width mismatches between E type and ECD value. | |||
9576 | bool SameSign = (ECD->getInitVal().isSigned() | |||
9577 | == E->getType()->isSignedIntegerOrEnumerationType()); | |||
9578 | bool SameWidth = (ECD->getInitVal().getBitWidth() | |||
9579 | == Info.Ctx.getIntWidth(E->getType())); | |||
9580 | if (SameSign && SameWidth) | |||
9581 | return Success(ECD->getInitVal(), E); | |||
9582 | else { | |||
9583 | // Get rid of mismatch (otherwise Success assertions will fail) | |||
9584 | // by computing a new value matching the type of E. | |||
9585 | llvm::APSInt Val = ECD->getInitVal(); | |||
9586 | if (!SameSign) | |||
9587 | Val.setIsSigned(!ECD->getInitVal().isSigned()); | |||
9588 | if (!SameWidth) | |||
9589 | Val = Val.extOrTrunc(Info.Ctx.getIntWidth(E->getType())); | |||
9590 | return Success(Val, E); | |||
9591 | } | |||
9592 | } | |||
9593 | return false; | |||
9594 | } | |||
9595 | ||||
9596 | /// Values returned by __builtin_classify_type, chosen to match the values | |||
9597 | /// produced by GCC's builtin. | |||
9598 | enum class GCCTypeClass { | |||
9599 | None = -1, | |||
9600 | Void = 0, | |||
9601 | Integer = 1, | |||
9602 | // GCC reserves 2 for character types, but instead classifies them as | |||
9603 | // integers. | |||
9604 | Enum = 3, | |||
9605 | Bool = 4, | |||
9606 | Pointer = 5, | |||
9607 | // GCC reserves 6 for references, but appears to never use it (because | |||
9608 | // expressions never have reference type, presumably). | |||
9609 | PointerToDataMember = 7, | |||
9610 | RealFloat = 8, | |||
9611 | Complex = 9, | |||
9612 | // GCC reserves 10 for functions, but does not use it since GCC version 6 due | |||
9613 | // to decay to pointer. (Prior to version 6 it was only used in C++ mode). | |||
9614 | // GCC claims to reserve 11 for pointers to member functions, but *actually* | |||
9615 | // uses 12 for that purpose, same as for a class or struct. Maybe it | |||
9616 | // internally implements a pointer to member as a struct? Who knows. | |||
9617 | PointerToMemberFunction = 12, // Not a bug, see above. | |||
9618 | ClassOrStruct = 12, | |||
9619 | Union = 13, | |||
9620 | // GCC reserves 14 for arrays, but does not use it since GCC version 6 due to | |||
9621 | // decay to pointer. (Prior to version 6 it was only used in C++ mode). | |||
9622 | // GCC reserves 15 for strings, but actually uses 5 (pointer) for string | |||
9623 | // literals. | |||
9624 | }; | |||
9625 | ||||
9626 | /// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way | |||
9627 | /// as GCC. | |||
9628 | static GCCTypeClass | |||
9629 | EvaluateBuiltinClassifyType(QualType T, const LangOptions &LangOpts) { | |||
9630 | assert(!T->isDependentType() && "unexpected dependent type")((!T->isDependentType() && "unexpected dependent type" ) ? static_cast<void> (0) : __assert_fail ("!T->isDependentType() && \"unexpected dependent type\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9630, __PRETTY_FUNCTION__)); | |||
9631 | ||||
9632 | QualType CanTy = T.getCanonicalType(); | |||
9633 | const BuiltinType *BT = dyn_cast<BuiltinType>(CanTy); | |||
9634 | ||||
9635 | switch (CanTy->getTypeClass()) { | |||
9636 | #define TYPE(ID, BASE) | |||
9637 | #define DEPENDENT_TYPE(ID, BASE) case Type::ID: | |||
9638 | #define NON_CANONICAL_TYPE(ID, BASE) case Type::ID: | |||
9639 | #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(ID, BASE) case Type::ID: | |||
9640 | #include "clang/AST/TypeNodes.inc" | |||
9641 | case Type::Auto: | |||
9642 | case Type::DeducedTemplateSpecialization: | |||
9643 | llvm_unreachable("unexpected non-canonical or dependent type")::llvm::llvm_unreachable_internal("unexpected non-canonical or dependent type" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9643); | |||
9644 | ||||
9645 | case Type::Builtin: | |||
9646 | switch (BT->getKind()) { | |||
9647 | #define BUILTIN_TYPE(ID, SINGLETON_ID) | |||
9648 | #define SIGNED_TYPE(ID, SINGLETON_ID) \ | |||
9649 | case BuiltinType::ID: return GCCTypeClass::Integer; | |||
9650 | #define FLOATING_TYPE(ID, SINGLETON_ID) \ | |||
9651 | case BuiltinType::ID: return GCCTypeClass::RealFloat; | |||
9652 | #define PLACEHOLDER_TYPE(ID, SINGLETON_ID) \ | |||
9653 | case BuiltinType::ID: break; | |||
9654 | #include "clang/AST/BuiltinTypes.def" | |||
9655 | case BuiltinType::Void: | |||
9656 | return GCCTypeClass::Void; | |||
9657 | ||||
9658 | case BuiltinType::Bool: | |||
9659 | return GCCTypeClass::Bool; | |||
9660 | ||||
9661 | case BuiltinType::Char_U: | |||
9662 | case BuiltinType::UChar: | |||
9663 | case BuiltinType::WChar_U: | |||
9664 | case BuiltinType::Char8: | |||
9665 | case BuiltinType::Char16: | |||
9666 | case BuiltinType::Char32: | |||
9667 | case BuiltinType::UShort: | |||
9668 | case BuiltinType::UInt: | |||
9669 | case BuiltinType::ULong: | |||
9670 | case BuiltinType::ULongLong: | |||
9671 | case BuiltinType::UInt128: | |||
9672 | return GCCTypeClass::Integer; | |||
9673 | ||||
9674 | case BuiltinType::UShortAccum: | |||
9675 | case BuiltinType::UAccum: | |||
9676 | case BuiltinType::ULongAccum: | |||
9677 | case BuiltinType::UShortFract: | |||
9678 | case BuiltinType::UFract: | |||
9679 | case BuiltinType::ULongFract: | |||
9680 | case BuiltinType::SatUShortAccum: | |||
9681 | case BuiltinType::SatUAccum: | |||
9682 | case BuiltinType::SatULongAccum: | |||
9683 | case BuiltinType::SatUShortFract: | |||
9684 | case BuiltinType::SatUFract: | |||
9685 | case BuiltinType::SatULongFract: | |||
9686 | return GCCTypeClass::None; | |||
9687 | ||||
9688 | case BuiltinType::NullPtr: | |||
9689 | ||||
9690 | case BuiltinType::ObjCId: | |||
9691 | case BuiltinType::ObjCClass: | |||
9692 | case BuiltinType::ObjCSel: | |||
9693 | #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \ | |||
9694 | case BuiltinType::Id: | |||
9695 | #include "clang/Basic/OpenCLImageTypes.def" | |||
9696 | #define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \ | |||
9697 | case BuiltinType::Id: | |||
9698 | #include "clang/Basic/OpenCLExtensionTypes.def" | |||
9699 | case BuiltinType::OCLSampler: | |||
9700 | case BuiltinType::OCLEvent: | |||
9701 | case BuiltinType::OCLClkEvent: | |||
9702 | case BuiltinType::OCLQueue: | |||
9703 | case BuiltinType::OCLReserveID: | |||
9704 | #define SVE_TYPE(Name, Id, SingletonId) \ | |||
9705 | case BuiltinType::Id: | |||
9706 | #include "clang/Basic/AArch64SVEACLETypes.def" | |||
9707 | return GCCTypeClass::None; | |||
9708 | ||||
9709 | case BuiltinType::Dependent: | |||
9710 | llvm_unreachable("unexpected dependent type")::llvm::llvm_unreachable_internal("unexpected dependent type" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9710); | |||
9711 | }; | |||
9712 | llvm_unreachable("unexpected placeholder type")::llvm::llvm_unreachable_internal("unexpected placeholder type" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9712); | |||
9713 | ||||
9714 | case Type::Enum: | |||
9715 | return LangOpts.CPlusPlus ? GCCTypeClass::Enum : GCCTypeClass::Integer; | |||
9716 | ||||
9717 | case Type::Pointer: | |||
9718 | case Type::ConstantArray: | |||
9719 | case Type::VariableArray: | |||
9720 | case Type::IncompleteArray: | |||
9721 | case Type::FunctionNoProto: | |||
9722 | case Type::FunctionProto: | |||
9723 | return GCCTypeClass::Pointer; | |||
9724 | ||||
9725 | case Type::MemberPointer: | |||
9726 | return CanTy->isMemberDataPointerType() | |||
9727 | ? GCCTypeClass::PointerToDataMember | |||
9728 | : GCCTypeClass::PointerToMemberFunction; | |||
9729 | ||||
9730 | case Type::Complex: | |||
9731 | return GCCTypeClass::Complex; | |||
9732 | ||||
9733 | case Type::Record: | |||
9734 | return CanTy->isUnionType() ? GCCTypeClass::Union | |||
9735 | : GCCTypeClass::ClassOrStruct; | |||
9736 | ||||
9737 | case Type::Atomic: | |||
9738 | // GCC classifies _Atomic T the same as T. | |||
9739 | return EvaluateBuiltinClassifyType( | |||
9740 | CanTy->castAs<AtomicType>()->getValueType(), LangOpts); | |||
9741 | ||||
9742 | case Type::BlockPointer: | |||
9743 | case Type::Vector: | |||
9744 | case Type::ExtVector: | |||
9745 | case Type::ObjCObject: | |||
9746 | case Type::ObjCInterface: | |||
9747 | case Type::ObjCObjectPointer: | |||
9748 | case Type::Pipe: | |||
9749 | // GCC classifies vectors as None. We follow its lead and classify all | |||
9750 | // other types that don't fit into the regular classification the same way. | |||
9751 | return GCCTypeClass::None; | |||
9752 | ||||
9753 | case Type::LValueReference: | |||
9754 | case Type::RValueReference: | |||
9755 | llvm_unreachable("invalid type for expression")::llvm::llvm_unreachable_internal("invalid type for expression" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9755); | |||
9756 | } | |||
9757 | ||||
9758 | llvm_unreachable("unexpected type class")::llvm::llvm_unreachable_internal("unexpected type class", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9758); | |||
9759 | } | |||
9760 | ||||
9761 | /// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way | |||
9762 | /// as GCC. | |||
9763 | static GCCTypeClass | |||
9764 | EvaluateBuiltinClassifyType(const CallExpr *E, const LangOptions &LangOpts) { | |||
9765 | // If no argument was supplied, default to None. This isn't | |||
9766 | // ideal, however it is what gcc does. | |||
9767 | if (E->getNumArgs() == 0) | |||
9768 | return GCCTypeClass::None; | |||
9769 | ||||
9770 | // FIXME: Bizarrely, GCC treats a call with more than one argument as not | |||
9771 | // being an ICE, but still folds it to a constant using the type of the first | |||
9772 | // argument. | |||
9773 | return EvaluateBuiltinClassifyType(E->getArg(0)->getType(), LangOpts); | |||
9774 | } | |||
9775 | ||||
9776 | /// EvaluateBuiltinConstantPForLValue - Determine the result of | |||
9777 | /// __builtin_constant_p when applied to the given pointer. | |||
9778 | /// | |||
9779 | /// A pointer is only "constant" if it is null (or a pointer cast to integer) | |||
9780 | /// or it points to the first character of a string literal. | |||
9781 | static bool EvaluateBuiltinConstantPForLValue(const APValue &LV) { | |||
9782 | APValue::LValueBase Base = LV.getLValueBase(); | |||
9783 | if (Base.isNull()) { | |||
9784 | // A null base is acceptable. | |||
9785 | return true; | |||
9786 | } else if (const Expr *E = Base.dyn_cast<const Expr *>()) { | |||
9787 | if (!isa<StringLiteral>(E)) | |||
9788 | return false; | |||
9789 | return LV.getLValueOffset().isZero(); | |||
9790 | } else if (Base.is<TypeInfoLValue>()) { | |||
9791 | // Surprisingly, GCC considers __builtin_constant_p(&typeid(int)) to | |||
9792 | // evaluate to true. | |||
9793 | return true; | |||
9794 | } else { | |||
9795 | // Any other base is not constant enough for GCC. | |||
9796 | return false; | |||
9797 | } | |||
9798 | } | |||
9799 | ||||
9800 | /// EvaluateBuiltinConstantP - Evaluate __builtin_constant_p as similarly to | |||
9801 | /// GCC as we can manage. | |||
9802 | static bool EvaluateBuiltinConstantP(EvalInfo &Info, const Expr *Arg) { | |||
9803 | // This evaluation is not permitted to have side-effects, so evaluate it in | |||
9804 | // a speculative evaluation context. | |||
9805 | SpeculativeEvaluationRAII SpeculativeEval(Info); | |||
9806 | ||||
9807 | // Constant-folding is always enabled for the operand of __builtin_constant_p | |||
9808 | // (even when the enclosing evaluation context otherwise requires a strict | |||
9809 | // language-specific constant expression). | |||
9810 | FoldConstant Fold(Info, true); | |||
9811 | ||||
9812 | QualType ArgType = Arg->getType(); | |||
9813 | ||||
9814 | // __builtin_constant_p always has one operand. The rules which gcc follows | |||
9815 | // are not precisely documented, but are as follows: | |||
9816 | // | |||
9817 | // - If the operand is of integral, floating, complex or enumeration type, | |||
9818 | // and can be folded to a known value of that type, it returns 1. | |||
9819 | // - If the operand can be folded to a pointer to the first character | |||
9820 | // of a string literal (or such a pointer cast to an integral type) | |||
9821 | // or to a null pointer or an integer cast to a pointer, it returns 1. | |||
9822 | // | |||
9823 | // Otherwise, it returns 0. | |||
9824 | // | |||
9825 | // FIXME: GCC also intends to return 1 for literals of aggregate types, but | |||
9826 | // its support for this did not work prior to GCC 9 and is not yet well | |||
9827 | // understood. | |||
9828 | if (ArgType->isIntegralOrEnumerationType() || ArgType->isFloatingType() || | |||
9829 | ArgType->isAnyComplexType() || ArgType->isPointerType() || | |||
9830 | ArgType->isNullPtrType()) { | |||
9831 | APValue V; | |||
9832 | if (!::EvaluateAsRValue(Info, Arg, V)) { | |||
9833 | Fold.keepDiagnostics(); | |||
9834 | return false; | |||
9835 | } | |||
9836 | ||||
9837 | // For a pointer (possibly cast to integer), there are special rules. | |||
9838 | if (V.getKind() == APValue::LValue) | |||
9839 | return EvaluateBuiltinConstantPForLValue(V); | |||
9840 | ||||
9841 | // Otherwise, any constant value is good enough. | |||
9842 | return V.hasValue(); | |||
9843 | } | |||
9844 | ||||
9845 | // Anything else isn't considered to be sufficiently constant. | |||
9846 | return false; | |||
9847 | } | |||
9848 | ||||
9849 | /// Retrieves the "underlying object type" of the given expression, | |||
9850 | /// as used by __builtin_object_size. | |||
9851 | static QualType getObjectType(APValue::LValueBase B) { | |||
9852 | if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) { | |||
9853 | if (const VarDecl *VD = dyn_cast<VarDecl>(D)) | |||
9854 | return VD->getType(); | |||
9855 | } else if (const Expr *E = B.get<const Expr*>()) { | |||
9856 | if (isa<CompoundLiteralExpr>(E)) | |||
9857 | return E->getType(); | |||
9858 | } else if (B.is<TypeInfoLValue>()) { | |||
9859 | return B.getTypeInfoType(); | |||
9860 | } else if (B.is<DynamicAllocLValue>()) { | |||
9861 | return B.getDynamicAllocType(); | |||
9862 | } | |||
9863 | ||||
9864 | return QualType(); | |||
9865 | } | |||
9866 | ||||
9867 | /// A more selective version of E->IgnoreParenCasts for | |||
9868 | /// tryEvaluateBuiltinObjectSize. This ignores some casts/parens that serve only | |||
9869 | /// to change the type of E. | |||
9870 | /// Ex. For E = `(short*)((char*)(&foo))`, returns `&foo` | |||
9871 | /// | |||
9872 | /// Always returns an RValue with a pointer representation. | |||
9873 | static const Expr *ignorePointerCastsAndParens(const Expr *E) { | |||
9874 | assert(E->isRValue() && E->getType()->hasPointerRepresentation())((E->isRValue() && E->getType()->hasPointerRepresentation ()) ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->hasPointerRepresentation()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9874, __PRETTY_FUNCTION__)); | |||
9875 | ||||
9876 | auto *NoParens = E->IgnoreParens(); | |||
9877 | auto *Cast = dyn_cast<CastExpr>(NoParens); | |||
9878 | if (Cast == nullptr) | |||
9879 | return NoParens; | |||
9880 | ||||
9881 | // We only conservatively allow a few kinds of casts, because this code is | |||
9882 | // inherently a simple solution that seeks to support the common case. | |||
9883 | auto CastKind = Cast->getCastKind(); | |||
9884 | if (CastKind != CK_NoOp && CastKind != CK_BitCast && | |||
9885 | CastKind != CK_AddressSpaceConversion) | |||
9886 | return NoParens; | |||
9887 | ||||
9888 | auto *SubExpr = Cast->getSubExpr(); | |||
9889 | if (!SubExpr->getType()->hasPointerRepresentation() || !SubExpr->isRValue()) | |||
9890 | return NoParens; | |||
9891 | return ignorePointerCastsAndParens(SubExpr); | |||
9892 | } | |||
9893 | ||||
9894 | /// Checks to see if the given LValue's Designator is at the end of the LValue's | |||
9895 | /// record layout. e.g. | |||
9896 | /// struct { struct { int a, b; } fst, snd; } obj; | |||
9897 | /// obj.fst // no | |||
9898 | /// obj.snd // yes | |||
9899 | /// obj.fst.a // no | |||
9900 | /// obj.fst.b // no | |||
9901 | /// obj.snd.a // no | |||
9902 | /// obj.snd.b // yes | |||
9903 | /// | |||
9904 | /// Please note: this function is specialized for how __builtin_object_size | |||
9905 | /// views "objects". | |||
9906 | /// | |||
9907 | /// If this encounters an invalid RecordDecl or otherwise cannot determine the | |||
9908 | /// correct result, it will always return true. | |||
9909 | static bool isDesignatorAtObjectEnd(const ASTContext &Ctx, const LValue &LVal) { | |||
9910 | assert(!LVal.Designator.Invalid)((!LVal.Designator.Invalid) ? static_cast<void> (0) : __assert_fail ("!LVal.Designator.Invalid", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9910, __PRETTY_FUNCTION__)); | |||
9911 | ||||
9912 | auto IsLastOrInvalidFieldDecl = [&Ctx](const FieldDecl *FD, bool &Invalid) { | |||
9913 | const RecordDecl *Parent = FD->getParent(); | |||
9914 | Invalid = Parent->isInvalidDecl(); | |||
9915 | if (Invalid || Parent->isUnion()) | |||
9916 | return true; | |||
9917 | const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(Parent); | |||
9918 | return FD->getFieldIndex() + 1 == Layout.getFieldCount(); | |||
9919 | }; | |||
9920 | ||||
9921 | auto &Base = LVal.getLValueBase(); | |||
9922 | if (auto *ME = dyn_cast_or_null<MemberExpr>(Base.dyn_cast<const Expr *>())) { | |||
9923 | if (auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) { | |||
9924 | bool Invalid; | |||
9925 | if (!IsLastOrInvalidFieldDecl(FD, Invalid)) | |||
9926 | return Invalid; | |||
9927 | } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(ME->getMemberDecl())) { | |||
9928 | for (auto *FD : IFD->chain()) { | |||
9929 | bool Invalid; | |||
9930 | if (!IsLastOrInvalidFieldDecl(cast<FieldDecl>(FD), Invalid)) | |||
9931 | return Invalid; | |||
9932 | } | |||
9933 | } | |||
9934 | } | |||
9935 | ||||
9936 | unsigned I = 0; | |||
9937 | QualType BaseType = getType(Base); | |||
9938 | if (LVal.Designator.FirstEntryIsAnUnsizedArray) { | |||
9939 | // If we don't know the array bound, conservatively assume we're looking at | |||
9940 | // the final array element. | |||
9941 | ++I; | |||
9942 | if (BaseType->isIncompleteArrayType()) | |||
9943 | BaseType = Ctx.getAsArrayType(BaseType)->getElementType(); | |||
9944 | else | |||
9945 | BaseType = BaseType->castAs<PointerType>()->getPointeeType(); | |||
9946 | } | |||
9947 | ||||
9948 | for (unsigned E = LVal.Designator.Entries.size(); I != E; ++I) { | |||
9949 | const auto &Entry = LVal.Designator.Entries[I]; | |||
9950 | if (BaseType->isArrayType()) { | |||
9951 | // Because __builtin_object_size treats arrays as objects, we can ignore | |||
9952 | // the index iff this is the last array in the Designator. | |||
9953 | if (I + 1 == E) | |||
9954 | return true; | |||
9955 | const auto *CAT = cast<ConstantArrayType>(Ctx.getAsArrayType(BaseType)); | |||
9956 | uint64_t Index = Entry.getAsArrayIndex(); | |||
9957 | if (Index + 1 != CAT->getSize()) | |||
9958 | return false; | |||
9959 | BaseType = CAT->getElementType(); | |||
9960 | } else if (BaseType->isAnyComplexType()) { | |||
9961 | const auto *CT = BaseType->castAs<ComplexType>(); | |||
9962 | uint64_t Index = Entry.getAsArrayIndex(); | |||
9963 | if (Index != 1) | |||
9964 | return false; | |||
9965 | BaseType = CT->getElementType(); | |||
9966 | } else if (auto *FD = getAsField(Entry)) { | |||
9967 | bool Invalid; | |||
9968 | if (!IsLastOrInvalidFieldDecl(FD, Invalid)) | |||
9969 | return Invalid; | |||
9970 | BaseType = FD->getType(); | |||
9971 | } else { | |||
9972 | assert(getAsBaseClass(Entry) && "Expecting cast to a base class")((getAsBaseClass(Entry) && "Expecting cast to a base class" ) ? static_cast<void> (0) : __assert_fail ("getAsBaseClass(Entry) && \"Expecting cast to a base class\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 9972, __PRETTY_FUNCTION__)); | |||
9973 | return false; | |||
9974 | } | |||
9975 | } | |||
9976 | return true; | |||
9977 | } | |||
9978 | ||||
9979 | /// Tests to see if the LValue has a user-specified designator (that isn't | |||
9980 | /// necessarily valid). Note that this always returns 'true' if the LValue has | |||
9981 | /// an unsized array as its first designator entry, because there's currently no | |||
9982 | /// way to tell if the user typed *foo or foo[0]. | |||
9983 | static bool refersToCompleteObject(const LValue &LVal) { | |||
9984 | if (LVal.Designator.Invalid) | |||
9985 | return false; | |||
9986 | ||||
9987 | if (!LVal.Designator.Entries.empty()) | |||
9988 | return LVal.Designator.isMostDerivedAnUnsizedArray(); | |||
9989 | ||||
9990 | if (!LVal.InvalidBase) | |||
9991 | return true; | |||
9992 | ||||
9993 | // If `E` is a MemberExpr, then the first part of the designator is hiding in | |||
9994 | // the LValueBase. | |||
9995 | const auto *E = LVal.Base.dyn_cast<const Expr *>(); | |||
9996 | return !E || !isa<MemberExpr>(E); | |||
9997 | } | |||
9998 | ||||
9999 | /// Attempts to detect a user writing into a piece of memory that's impossible | |||
10000 | /// to figure out the size of by just using types. | |||
10001 | static bool isUserWritingOffTheEnd(const ASTContext &Ctx, const LValue &LVal) { | |||
10002 | const SubobjectDesignator &Designator = LVal.Designator; | |||
10003 | // Notes: | |||
10004 | // - Users can only write off of the end when we have an invalid base. Invalid | |||
10005 | // bases imply we don't know where the memory came from. | |||
10006 | // - We used to be a bit more aggressive here; we'd only be conservative if | |||
10007 | // the array at the end was flexible, or if it had 0 or 1 elements. This | |||
10008 | // broke some common standard library extensions (PR30346), but was | |||
10009 | // otherwise seemingly fine. It may be useful to reintroduce this behavior | |||
10010 | // with some sort of whitelist. OTOH, it seems that GCC is always | |||
10011 | // conservative with the last element in structs (if it's an array), so our | |||
10012 | // current behavior is more compatible than a whitelisting approach would | |||
10013 | // be. | |||
10014 | return LVal.InvalidBase && | |||
10015 | Designator.Entries.size() == Designator.MostDerivedPathLength && | |||
10016 | Designator.MostDerivedIsArrayElement && | |||
10017 | isDesignatorAtObjectEnd(Ctx, LVal); | |||
10018 | } | |||
10019 | ||||
10020 | /// Converts the given APInt to CharUnits, assuming the APInt is unsigned. | |||
10021 | /// Fails if the conversion would cause loss of precision. | |||
10022 | static bool convertUnsignedAPIntToCharUnits(const llvm::APInt &Int, | |||
10023 | CharUnits &Result) { | |||
10024 | auto CharUnitsMax = std::numeric_limits<CharUnits::QuantityType>::max(); | |||
10025 | if (Int.ugt(CharUnitsMax)) | |||
10026 | return false; | |||
10027 | Result = CharUnits::fromQuantity(Int.getZExtValue()); | |||
10028 | return true; | |||
10029 | } | |||
10030 | ||||
10031 | /// Helper for tryEvaluateBuiltinObjectSize -- Given an LValue, this will | |||
10032 | /// determine how many bytes exist from the beginning of the object to either | |||
10033 | /// the end of the current subobject, or the end of the object itself, depending | |||
10034 | /// on what the LValue looks like + the value of Type. | |||
10035 | /// | |||
10036 | /// If this returns false, the value of Result is undefined. | |||
10037 | static bool determineEndOffset(EvalInfo &Info, SourceLocation ExprLoc, | |||
10038 | unsigned Type, const LValue &LVal, | |||
10039 | CharUnits &EndOffset) { | |||
10040 | bool DetermineForCompleteObject = refersToCompleteObject(LVal); | |||
10041 | ||||
10042 | auto CheckedHandleSizeof = [&](QualType Ty, CharUnits &Result) { | |||
10043 | if (Ty.isNull() || Ty->isIncompleteType() || Ty->isFunctionType()) | |||
10044 | return false; | |||
10045 | return HandleSizeof(Info, ExprLoc, Ty, Result); | |||
10046 | }; | |||
10047 | ||||
10048 | // We want to evaluate the size of the entire object. This is a valid fallback | |||
10049 | // for when Type=1 and the designator is invalid, because we're asked for an | |||
10050 | // upper-bound. | |||
10051 | if (!(Type & 1) || LVal.Designator.Invalid || DetermineForCompleteObject) { | |||
10052 | // Type=3 wants a lower bound, so we can't fall back to this. | |||
10053 | if (Type == 3 && !DetermineForCompleteObject) | |||
10054 | return false; | |||
10055 | ||||
10056 | llvm::APInt APEndOffset; | |||
10057 | if (isBaseAnAllocSizeCall(LVal.getLValueBase()) && | |||
10058 | getBytesReturnedByAllocSizeCall(Info.Ctx, LVal, APEndOffset)) | |||
10059 | return convertUnsignedAPIntToCharUnits(APEndOffset, EndOffset); | |||
10060 | ||||
10061 | if (LVal.InvalidBase) | |||
10062 | return false; | |||
10063 | ||||
10064 | QualType BaseTy = getObjectType(LVal.getLValueBase()); | |||
10065 | return CheckedHandleSizeof(BaseTy, EndOffset); | |||
10066 | } | |||
10067 | ||||
10068 | // We want to evaluate the size of a subobject. | |||
10069 | const SubobjectDesignator &Designator = LVal.Designator; | |||
10070 | ||||
10071 | // The following is a moderately common idiom in C: | |||
10072 | // | |||
10073 | // struct Foo { int a; char c[1]; }; | |||
10074 | // struct Foo *F = (struct Foo *)malloc(sizeof(struct Foo) + strlen(Bar)); | |||
10075 | // strcpy(&F->c[0], Bar); | |||
10076 | // | |||
10077 | // In order to not break too much legacy code, we need to support it. | |||
10078 | if (isUserWritingOffTheEnd(Info.Ctx, LVal)) { | |||
10079 | // If we can resolve this to an alloc_size call, we can hand that back, | |||
10080 | // because we know for certain how many bytes there are to write to. | |||
10081 | llvm::APInt APEndOffset; | |||
10082 | if (isBaseAnAllocSizeCall(LVal.getLValueBase()) && | |||
10083 | getBytesReturnedByAllocSizeCall(Info.Ctx, LVal, APEndOffset)) | |||
10084 | return convertUnsignedAPIntToCharUnits(APEndOffset, EndOffset); | |||
10085 | ||||
10086 | // If we cannot determine the size of the initial allocation, then we can't | |||
10087 | // given an accurate upper-bound. However, we are still able to give | |||
10088 | // conservative lower-bounds for Type=3. | |||
10089 | if (Type == 1) | |||
10090 | return false; | |||
10091 | } | |||
10092 | ||||
10093 | CharUnits BytesPerElem; | |||
10094 | if (!CheckedHandleSizeof(Designator.MostDerivedType, BytesPerElem)) | |||
10095 | return false; | |||
10096 | ||||
10097 | // According to the GCC documentation, we want the size of the subobject | |||
10098 | // denoted by the pointer. But that's not quite right -- what we actually | |||
10099 | // want is the size of the immediately-enclosing array, if there is one. | |||
10100 | int64_t ElemsRemaining; | |||
10101 | if (Designator.MostDerivedIsArrayElement && | |||
10102 | Designator.Entries.size() == Designator.MostDerivedPathLength) { | |||
10103 | uint64_t ArraySize = Designator.getMostDerivedArraySize(); | |||
10104 | uint64_t ArrayIndex = Designator.Entries.back().getAsArrayIndex(); | |||
10105 | ElemsRemaining = ArraySize <= ArrayIndex ? 0 : ArraySize - ArrayIndex; | |||
10106 | } else { | |||
10107 | ElemsRemaining = Designator.isOnePastTheEnd() ? 0 : 1; | |||
10108 | } | |||
10109 | ||||
10110 | EndOffset = LVal.getLValueOffset() + BytesPerElem * ElemsRemaining; | |||
10111 | return true; | |||
10112 | } | |||
10113 | ||||
10114 | /// Tries to evaluate the __builtin_object_size for @p E. If successful, | |||
10115 | /// returns true and stores the result in @p Size. | |||
10116 | /// | |||
10117 | /// If @p WasError is non-null, this will report whether the failure to evaluate | |||
10118 | /// is to be treated as an Error in IntExprEvaluator. | |||
10119 | static bool tryEvaluateBuiltinObjectSize(const Expr *E, unsigned Type, | |||
10120 | EvalInfo &Info, uint64_t &Size) { | |||
10121 | // Determine the denoted object. | |||
10122 | LValue LVal; | |||
10123 | { | |||
10124 | // The operand of __builtin_object_size is never evaluated for side-effects. | |||
10125 | // If there are any, but we can determine the pointed-to object anyway, then | |||
10126 | // ignore the side-effects. | |||
10127 | SpeculativeEvaluationRAII SpeculativeEval(Info); | |||
10128 | IgnoreSideEffectsRAII Fold(Info); | |||
10129 | ||||
10130 | if (E->isGLValue()) { | |||
10131 | // It's possible for us to be given GLValues if we're called via | |||
10132 | // Expr::tryEvaluateObjectSize. | |||
10133 | APValue RVal; | |||
10134 | if (!EvaluateAsRValue(Info, E, RVal)) | |||
10135 | return false; | |||
10136 | LVal.setFrom(Info.Ctx, RVal); | |||
10137 | } else if (!EvaluatePointer(ignorePointerCastsAndParens(E), LVal, Info, | |||
10138 | /*InvalidBaseOK=*/true)) | |||
10139 | return false; | |||
10140 | } | |||
10141 | ||||
10142 | // If we point to before the start of the object, there are no accessible | |||
10143 | // bytes. | |||
10144 | if (LVal.getLValueOffset().isNegative()) { | |||
10145 | Size = 0; | |||
10146 | return true; | |||
10147 | } | |||
10148 | ||||
10149 | CharUnits EndOffset; | |||
10150 | if (!determineEndOffset(Info, E->getExprLoc(), Type, LVal, EndOffset)) | |||
10151 | return false; | |||
10152 | ||||
10153 | // If we've fallen outside of the end offset, just pretend there's nothing to | |||
10154 | // write to/read from. | |||
10155 | if (EndOffset <= LVal.getLValueOffset()) | |||
10156 | Size = 0; | |||
10157 | else | |||
10158 | Size = (EndOffset - LVal.getLValueOffset()).getQuantity(); | |||
10159 | return true; | |||
10160 | } | |||
10161 | ||||
10162 | bool IntExprEvaluator::VisitConstantExpr(const ConstantExpr *E) { | |||
10163 | llvm::SaveAndRestore<bool> InConstantContext(Info.InConstantContext, true); | |||
10164 | if (E->getResultAPValueKind() != APValue::None) | |||
10165 | return Success(E->getAPValueResult(), E); | |||
10166 | return ExprEvaluatorBaseTy::VisitConstantExpr(E); | |||
10167 | } | |||
10168 | ||||
10169 | bool IntExprEvaluator::VisitCallExpr(const CallExpr *E) { | |||
10170 | if (unsigned BuiltinOp = E->getBuiltinCallee()) | |||
10171 | return VisitBuiltinCallExpr(E, BuiltinOp); | |||
10172 | ||||
10173 | return ExprEvaluatorBaseTy::VisitCallExpr(E); | |||
10174 | } | |||
10175 | ||||
10176 | bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E, | |||
10177 | unsigned BuiltinOp) { | |||
10178 | switch (unsigned BuiltinOp = E->getBuiltinCallee()) { | |||
10179 | default: | |||
10180 | return ExprEvaluatorBaseTy::VisitCallExpr(E); | |||
10181 | ||||
10182 | case Builtin::BI__builtin_dynamic_object_size: | |||
10183 | case Builtin::BI__builtin_object_size: { | |||
10184 | // The type was checked when we built the expression. | |||
10185 | unsigned Type = | |||
10186 | E->getArg(1)->EvaluateKnownConstInt(Info.Ctx).getZExtValue(); | |||
10187 | assert(Type <= 3 && "unexpected type")((Type <= 3 && "unexpected type") ? static_cast< void> (0) : __assert_fail ("Type <= 3 && \"unexpected type\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10187, __PRETTY_FUNCTION__)); | |||
10188 | ||||
10189 | uint64_t Size; | |||
10190 | if (tryEvaluateBuiltinObjectSize(E->getArg(0), Type, Info, Size)) | |||
10191 | return Success(Size, E); | |||
10192 | ||||
10193 | if (E->getArg(0)->HasSideEffects(Info.Ctx)) | |||
10194 | return Success((Type & 2) ? 0 : -1, E); | |||
10195 | ||||
10196 | // Expression had no side effects, but we couldn't statically determine the | |||
10197 | // size of the referenced object. | |||
10198 | switch (Info.EvalMode) { | |||
10199 | case EvalInfo::EM_ConstantExpression: | |||
10200 | case EvalInfo::EM_ConstantFold: | |||
10201 | case EvalInfo::EM_IgnoreSideEffects: | |||
10202 | // Leave it to IR generation. | |||
10203 | return Error(E); | |||
10204 | case EvalInfo::EM_ConstantExpressionUnevaluated: | |||
10205 | // Reduce it to a constant now. | |||
10206 | return Success((Type & 2) ? 0 : -1, E); | |||
10207 | } | |||
10208 | ||||
10209 | llvm_unreachable("unexpected EvalMode")::llvm::llvm_unreachable_internal("unexpected EvalMode", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10209); | |||
10210 | } | |||
10211 | ||||
10212 | case Builtin::BI__builtin_os_log_format_buffer_size: { | |||
10213 | analyze_os_log::OSLogBufferLayout Layout; | |||
10214 | analyze_os_log::computeOSLogBufferLayout(Info.Ctx, E, Layout); | |||
10215 | return Success(Layout.size().getQuantity(), E); | |||
10216 | } | |||
10217 | ||||
10218 | case Builtin::BI__builtin_bswap16: | |||
10219 | case Builtin::BI__builtin_bswap32: | |||
10220 | case Builtin::BI__builtin_bswap64: { | |||
10221 | APSInt Val; | |||
10222 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
10223 | return false; | |||
10224 | ||||
10225 | return Success(Val.byteSwap(), E); | |||
10226 | } | |||
10227 | ||||
10228 | case Builtin::BI__builtin_classify_type: | |||
10229 | return Success((int)EvaluateBuiltinClassifyType(E, Info.getLangOpts()), E); | |||
10230 | ||||
10231 | case Builtin::BI__builtin_clrsb: | |||
10232 | case Builtin::BI__builtin_clrsbl: | |||
10233 | case Builtin::BI__builtin_clrsbll: { | |||
10234 | APSInt Val; | |||
10235 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
10236 | return false; | |||
10237 | ||||
10238 | return Success(Val.getBitWidth() - Val.getMinSignedBits(), E); | |||
10239 | } | |||
10240 | ||||
10241 | case Builtin::BI__builtin_clz: | |||
10242 | case Builtin::BI__builtin_clzl: | |||
10243 | case Builtin::BI__builtin_clzll: | |||
10244 | case Builtin::BI__builtin_clzs: { | |||
10245 | APSInt Val; | |||
10246 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
10247 | return false; | |||
10248 | if (!Val) | |||
10249 | return Error(E); | |||
10250 | ||||
10251 | return Success(Val.countLeadingZeros(), E); | |||
10252 | } | |||
10253 | ||||
10254 | case Builtin::BI__builtin_constant_p: { | |||
10255 | const Expr *Arg = E->getArg(0); | |||
10256 | if (EvaluateBuiltinConstantP(Info, Arg)) | |||
10257 | return Success(true, E); | |||
10258 | if (Info.InConstantContext || Arg->HasSideEffects(Info.Ctx)) { | |||
10259 | // Outside a constant context, eagerly evaluate to false in the presence | |||
10260 | // of side-effects in order to avoid -Wunsequenced false-positives in | |||
10261 | // a branch on __builtin_constant_p(expr). | |||
10262 | return Success(false, E); | |||
10263 | } | |||
10264 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
10265 | return false; | |||
10266 | } | |||
10267 | ||||
10268 | case Builtin::BI__builtin_is_constant_evaluated: | |||
10269 | return Success(Info.InConstantContext, E); | |||
10270 | ||||
10271 | case Builtin::BI__builtin_ctz: | |||
10272 | case Builtin::BI__builtin_ctzl: | |||
10273 | case Builtin::BI__builtin_ctzll: | |||
10274 | case Builtin::BI__builtin_ctzs: { | |||
10275 | APSInt Val; | |||
10276 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
10277 | return false; | |||
10278 | if (!Val) | |||
10279 | return Error(E); | |||
10280 | ||||
10281 | return Success(Val.countTrailingZeros(), E); | |||
10282 | } | |||
10283 | ||||
10284 | case Builtin::BI__builtin_eh_return_data_regno: { | |||
10285 | int Operand = E->getArg(0)->EvaluateKnownConstInt(Info.Ctx).getZExtValue(); | |||
10286 | Operand = Info.Ctx.getTargetInfo().getEHDataRegisterNumber(Operand); | |||
10287 | return Success(Operand, E); | |||
10288 | } | |||
10289 | ||||
10290 | case Builtin::BI__builtin_expect: | |||
10291 | return Visit(E->getArg(0)); | |||
10292 | ||||
10293 | case Builtin::BI__builtin_ffs: | |||
10294 | case Builtin::BI__builtin_ffsl: | |||
10295 | case Builtin::BI__builtin_ffsll: { | |||
10296 | APSInt Val; | |||
10297 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
10298 | return false; | |||
10299 | ||||
10300 | unsigned N = Val.countTrailingZeros(); | |||
10301 | return Success(N == Val.getBitWidth() ? 0 : N + 1, E); | |||
10302 | } | |||
10303 | ||||
10304 | case Builtin::BI__builtin_fpclassify: { | |||
10305 | APFloat Val(0.0); | |||
10306 | if (!EvaluateFloat(E->getArg(5), Val, Info)) | |||
10307 | return false; | |||
10308 | unsigned Arg; | |||
10309 | switch (Val.getCategory()) { | |||
10310 | case APFloat::fcNaN: Arg = 0; break; | |||
10311 | case APFloat::fcInfinity: Arg = 1; break; | |||
10312 | case APFloat::fcNormal: Arg = Val.isDenormal() ? 3 : 2; break; | |||
10313 | case APFloat::fcZero: Arg = 4; break; | |||
10314 | } | |||
10315 | return Visit(E->getArg(Arg)); | |||
10316 | } | |||
10317 | ||||
10318 | case Builtin::BI__builtin_isinf_sign: { | |||
10319 | APFloat Val(0.0); | |||
10320 | return EvaluateFloat(E->getArg(0), Val, Info) && | |||
10321 | Success(Val.isInfinity() ? (Val.isNegative() ? -1 : 1) : 0, E); | |||
10322 | } | |||
10323 | ||||
10324 | case Builtin::BI__builtin_isinf: { | |||
10325 | APFloat Val(0.0); | |||
10326 | return EvaluateFloat(E->getArg(0), Val, Info) && | |||
10327 | Success(Val.isInfinity() ? 1 : 0, E); | |||
10328 | } | |||
10329 | ||||
10330 | case Builtin::BI__builtin_isfinite: { | |||
10331 | APFloat Val(0.0); | |||
10332 | return EvaluateFloat(E->getArg(0), Val, Info) && | |||
10333 | Success(Val.isFinite() ? 1 : 0, E); | |||
10334 | } | |||
10335 | ||||
10336 | case Builtin::BI__builtin_isnan: { | |||
10337 | APFloat Val(0.0); | |||
10338 | return EvaluateFloat(E->getArg(0), Val, Info) && | |||
10339 | Success(Val.isNaN() ? 1 : 0, E); | |||
10340 | } | |||
10341 | ||||
10342 | case Builtin::BI__builtin_isnormal: { | |||
10343 | APFloat Val(0.0); | |||
10344 | return EvaluateFloat(E->getArg(0), Val, Info) && | |||
10345 | Success(Val.isNormal() ? 1 : 0, E); | |||
10346 | } | |||
10347 | ||||
10348 | case Builtin::BI__builtin_parity: | |||
10349 | case Builtin::BI__builtin_parityl: | |||
10350 | case Builtin::BI__builtin_parityll: { | |||
10351 | APSInt Val; | |||
10352 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
10353 | return false; | |||
10354 | ||||
10355 | return Success(Val.countPopulation() % 2, E); | |||
10356 | } | |||
10357 | ||||
10358 | case Builtin::BI__builtin_popcount: | |||
10359 | case Builtin::BI__builtin_popcountl: | |||
10360 | case Builtin::BI__builtin_popcountll: { | |||
10361 | APSInt Val; | |||
10362 | if (!EvaluateInteger(E->getArg(0), Val, Info)) | |||
10363 | return false; | |||
10364 | ||||
10365 | return Success(Val.countPopulation(), E); | |||
10366 | } | |||
10367 | ||||
10368 | case Builtin::BIstrlen: | |||
10369 | case Builtin::BIwcslen: | |||
10370 | // A call to strlen is not a constant expression. | |||
10371 | if (Info.getLangOpts().CPlusPlus11) | |||
10372 | Info.CCEDiag(E, diag::note_constexpr_invalid_function) | |||
10373 | << /*isConstexpr*/0 << /*isConstructor*/0 | |||
10374 | << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'"); | |||
10375 | else | |||
10376 | Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
10377 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
10378 | case Builtin::BI__builtin_strlen: | |||
10379 | case Builtin::BI__builtin_wcslen: { | |||
10380 | // As an extension, we support __builtin_strlen() as a constant expression, | |||
10381 | // and support folding strlen() to a constant. | |||
10382 | LValue String; | |||
10383 | if (!EvaluatePointer(E->getArg(0), String, Info)) | |||
10384 | return false; | |||
10385 | ||||
10386 | QualType CharTy = E->getArg(0)->getType()->getPointeeType(); | |||
10387 | ||||
10388 | // Fast path: if it's a string literal, search the string value. | |||
10389 | if (const StringLiteral *S = dyn_cast_or_null<StringLiteral>( | |||
10390 | String.getLValueBase().dyn_cast<const Expr *>())) { | |||
10391 | // The string literal may have embedded null characters. Find the first | |||
10392 | // one and truncate there. | |||
10393 | StringRef Str = S->getBytes(); | |||
10394 | int64_t Off = String.Offset.getQuantity(); | |||
10395 | if (Off >= 0 && (uint64_t)Off <= (uint64_t)Str.size() && | |||
10396 | S->getCharByteWidth() == 1 && | |||
10397 | // FIXME: Add fast-path for wchar_t too. | |||
10398 | Info.Ctx.hasSameUnqualifiedType(CharTy, Info.Ctx.CharTy)) { | |||
10399 | Str = Str.substr(Off); | |||
10400 | ||||
10401 | StringRef::size_type Pos = Str.find(0); | |||
10402 | if (Pos != StringRef::npos) | |||
10403 | Str = Str.substr(0, Pos); | |||
10404 | ||||
10405 | return Success(Str.size(), E); | |||
10406 | } | |||
10407 | ||||
10408 | // Fall through to slow path to issue appropriate diagnostic. | |||
10409 | } | |||
10410 | ||||
10411 | // Slow path: scan the bytes of the string looking for the terminating 0. | |||
10412 | for (uint64_t Strlen = 0; /**/; ++Strlen) { | |||
10413 | APValue Char; | |||
10414 | if (!handleLValueToRValueConversion(Info, E, CharTy, String, Char) || | |||
10415 | !Char.isInt()) | |||
10416 | return false; | |||
10417 | if (!Char.getInt()) | |||
10418 | return Success(Strlen, E); | |||
10419 | if (!HandleLValueArrayAdjustment(Info, E, String, CharTy, 1)) | |||
10420 | return false; | |||
10421 | } | |||
10422 | } | |||
10423 | ||||
10424 | case Builtin::BIstrcmp: | |||
10425 | case Builtin::BIwcscmp: | |||
10426 | case Builtin::BIstrncmp: | |||
10427 | case Builtin::BIwcsncmp: | |||
10428 | case Builtin::BImemcmp: | |||
10429 | case Builtin::BIbcmp: | |||
10430 | case Builtin::BIwmemcmp: | |||
10431 | // A call to strlen is not a constant expression. | |||
10432 | if (Info.getLangOpts().CPlusPlus11) | |||
10433 | Info.CCEDiag(E, diag::note_constexpr_invalid_function) | |||
10434 | << /*isConstexpr*/0 << /*isConstructor*/0 | |||
10435 | << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'"); | |||
10436 | else | |||
10437 | Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
10438 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | |||
10439 | case Builtin::BI__builtin_strcmp: | |||
10440 | case Builtin::BI__builtin_wcscmp: | |||
10441 | case Builtin::BI__builtin_strncmp: | |||
10442 | case Builtin::BI__builtin_wcsncmp: | |||
10443 | case Builtin::BI__builtin_memcmp: | |||
10444 | case Builtin::BI__builtin_bcmp: | |||
10445 | case Builtin::BI__builtin_wmemcmp: { | |||
10446 | LValue String1, String2; | |||
10447 | if (!EvaluatePointer(E->getArg(0), String1, Info) || | |||
10448 | !EvaluatePointer(E->getArg(1), String2, Info)) | |||
10449 | return false; | |||
10450 | ||||
10451 | uint64_t MaxLength = uint64_t(-1); | |||
10452 | if (BuiltinOp != Builtin::BIstrcmp && | |||
10453 | BuiltinOp != Builtin::BIwcscmp && | |||
10454 | BuiltinOp != Builtin::BI__builtin_strcmp && | |||
10455 | BuiltinOp != Builtin::BI__builtin_wcscmp) { | |||
10456 | APSInt N; | |||
10457 | if (!EvaluateInteger(E->getArg(2), N, Info)) | |||
10458 | return false; | |||
10459 | MaxLength = N.getExtValue(); | |||
10460 | } | |||
10461 | ||||
10462 | // Empty substrings compare equal by definition. | |||
10463 | if (MaxLength == 0u) | |||
10464 | return Success(0, E); | |||
10465 | ||||
10466 | if (!String1.checkNullPointerForFoldAccess(Info, E, AK_Read) || | |||
10467 | !String2.checkNullPointerForFoldAccess(Info, E, AK_Read) || | |||
10468 | String1.Designator.Invalid || String2.Designator.Invalid) | |||
10469 | return false; | |||
10470 | ||||
10471 | QualType CharTy1 = String1.Designator.getType(Info.Ctx); | |||
10472 | QualType CharTy2 = String2.Designator.getType(Info.Ctx); | |||
10473 | ||||
10474 | bool IsRawByte = BuiltinOp == Builtin::BImemcmp || | |||
10475 | BuiltinOp == Builtin::BIbcmp || | |||
10476 | BuiltinOp == Builtin::BI__builtin_memcmp || | |||
10477 | BuiltinOp == Builtin::BI__builtin_bcmp; | |||
10478 | ||||
10479 | assert(IsRawByte ||((IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E-> getArg(0)->getType()->getPointeeType()) && Info .Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))) ? static_cast <void> (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10482, __PRETTY_FUNCTION__)) | |||
10480 | (Info.Ctx.hasSameUnqualifiedType(((IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E-> getArg(0)->getType()->getPointeeType()) && Info .Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))) ? static_cast <void> (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10482, __PRETTY_FUNCTION__)) | |||
10481 | CharTy1, E->getArg(0)->getType()->getPointeeType()) &&((IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E-> getArg(0)->getType()->getPointeeType()) && Info .Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))) ? static_cast <void> (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10482, __PRETTY_FUNCTION__)) | |||
10482 | Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2)))((IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E-> getArg(0)->getType()->getPointeeType()) && Info .Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))) ? static_cast <void> (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10482, __PRETTY_FUNCTION__)); | |||
10483 | ||||
10484 | const auto &ReadCurElems = [&](APValue &Char1, APValue &Char2) { | |||
10485 | return handleLValueToRValueConversion(Info, E, CharTy1, String1, Char1) && | |||
10486 | handleLValueToRValueConversion(Info, E, CharTy2, String2, Char2) && | |||
10487 | Char1.isInt() && Char2.isInt(); | |||
10488 | }; | |||
10489 | const auto &AdvanceElems = [&] { | |||
10490 | return HandleLValueArrayAdjustment(Info, E, String1, CharTy1, 1) && | |||
10491 | HandleLValueArrayAdjustment(Info, E, String2, CharTy2, 1); | |||
10492 | }; | |||
10493 | ||||
10494 | if (IsRawByte) { | |||
10495 | uint64_t BytesRemaining = MaxLength; | |||
10496 | // Pointers to const void may point to objects of incomplete type. | |||
10497 | if (CharTy1->isIncompleteType()) { | |||
10498 | Info.FFDiag(E, diag::note_constexpr_ltor_incomplete_type) << CharTy1; | |||
10499 | return false; | |||
10500 | } | |||
10501 | if (CharTy2->isIncompleteType()) { | |||
10502 | Info.FFDiag(E, diag::note_constexpr_ltor_incomplete_type) << CharTy2; | |||
10503 | return false; | |||
10504 | } | |||
10505 | uint64_t CharTy1Width{Info.Ctx.getTypeSize(CharTy1)}; | |||
10506 | CharUnits CharTy1Size = Info.Ctx.toCharUnitsFromBits(CharTy1Width); | |||
10507 | // Give up on comparing between elements with disparate widths. | |||
10508 | if (CharTy1Size != Info.Ctx.getTypeSizeInChars(CharTy2)) | |||
10509 | return false; | |||
10510 | uint64_t BytesPerElement = CharTy1Size.getQuantity(); | |||
10511 | assert(BytesRemaining && "BytesRemaining should not be zero: the "((BytesRemaining && "BytesRemaining should not be zero: the " "following loop considers at least one element") ? static_cast <void> (0) : __assert_fail ("BytesRemaining && \"BytesRemaining should not be zero: the \" \"following loop considers at least one element\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10512, __PRETTY_FUNCTION__)) | |||
10512 | "following loop considers at least one element")((BytesRemaining && "BytesRemaining should not be zero: the " "following loop considers at least one element") ? static_cast <void> (0) : __assert_fail ("BytesRemaining && \"BytesRemaining should not be zero: the \" \"following loop considers at least one element\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10512, __PRETTY_FUNCTION__)); | |||
10513 | while (true) { | |||
10514 | APValue Char1, Char2; | |||
10515 | if (!ReadCurElems(Char1, Char2)) | |||
10516 | return false; | |||
10517 | // We have compatible in-memory widths, but a possible type and | |||
10518 | // (for `bool`) internal representation mismatch. | |||
10519 | // Assuming two's complement representation, including 0 for `false` and | |||
10520 | // 1 for `true`, we can check an appropriate number of elements for | |||
10521 | // equality even if they are not byte-sized. | |||
10522 | APSInt Char1InMem = Char1.getInt().extOrTrunc(CharTy1Width); | |||
10523 | APSInt Char2InMem = Char2.getInt().extOrTrunc(CharTy1Width); | |||
10524 | if (Char1InMem.ne(Char2InMem)) { | |||
10525 | // If the elements are byte-sized, then we can produce a three-way | |||
10526 | // comparison result in a straightforward manner. | |||
10527 | if (BytesPerElement == 1u) { | |||
10528 | // memcmp always compares unsigned chars. | |||
10529 | return Success(Char1InMem.ult(Char2InMem) ? -1 : 1, E); | |||
10530 | } | |||
10531 | // The result is byte-order sensitive, and we have multibyte elements. | |||
10532 | // FIXME: We can compare the remaining bytes in the correct order. | |||
10533 | return false; | |||
10534 | } | |||
10535 | if (!AdvanceElems()) | |||
10536 | return false; | |||
10537 | if (BytesRemaining <= BytesPerElement) | |||
10538 | break; | |||
10539 | BytesRemaining -= BytesPerElement; | |||
10540 | } | |||
10541 | // Enough elements are equal to account for the memcmp limit. | |||
10542 | return Success(0, E); | |||
10543 | } | |||
10544 | ||||
10545 | bool StopAtNull = | |||
10546 | (BuiltinOp != Builtin::BImemcmp && BuiltinOp != Builtin::BIbcmp && | |||
10547 | BuiltinOp != Builtin::BIwmemcmp && | |||
10548 | BuiltinOp != Builtin::BI__builtin_memcmp && | |||
10549 | BuiltinOp != Builtin::BI__builtin_bcmp && | |||
10550 | BuiltinOp != Builtin::BI__builtin_wmemcmp); | |||
10551 | bool IsWide = BuiltinOp == Builtin::BIwcscmp || | |||
10552 | BuiltinOp == Builtin::BIwcsncmp || | |||
10553 | BuiltinOp == Builtin::BIwmemcmp || | |||
10554 | BuiltinOp == Builtin::BI__builtin_wcscmp || | |||
10555 | BuiltinOp == Builtin::BI__builtin_wcsncmp || | |||
10556 | BuiltinOp == Builtin::BI__builtin_wmemcmp; | |||
10557 | ||||
10558 | for (; MaxLength; --MaxLength) { | |||
10559 | APValue Char1, Char2; | |||
10560 | if (!ReadCurElems(Char1, Char2)) | |||
10561 | return false; | |||
10562 | if (Char1.getInt() != Char2.getInt()) { | |||
10563 | if (IsWide) // wmemcmp compares with wchar_t signedness. | |||
10564 | return Success(Char1.getInt() < Char2.getInt() ? -1 : 1, E); | |||
10565 | // memcmp always compares unsigned chars. | |||
10566 | return Success(Char1.getInt().ult(Char2.getInt()) ? -1 : 1, E); | |||
10567 | } | |||
10568 | if (StopAtNull && !Char1.getInt()) | |||
10569 | return Success(0, E); | |||
10570 | assert(!(StopAtNull && !Char2.getInt()))((!(StopAtNull && !Char2.getInt())) ? static_cast< void> (0) : __assert_fail ("!(StopAtNull && !Char2.getInt())" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10570, __PRETTY_FUNCTION__)); | |||
10571 | if (!AdvanceElems()) | |||
10572 | return false; | |||
10573 | } | |||
10574 | // We hit the strncmp / memcmp limit. | |||
10575 | return Success(0, E); | |||
10576 | } | |||
10577 | ||||
10578 | case Builtin::BI__atomic_always_lock_free: | |||
10579 | case Builtin::BI__atomic_is_lock_free: | |||
10580 | case Builtin::BI__c11_atomic_is_lock_free: { | |||
10581 | APSInt SizeVal; | |||
10582 | if (!EvaluateInteger(E->getArg(0), SizeVal, Info)) | |||
10583 | return false; | |||
10584 | ||||
10585 | // For __atomic_is_lock_free(sizeof(_Atomic(T))), if the size is a power | |||
10586 | // of two less than the maximum inline atomic width, we know it is | |||
10587 | // lock-free. If the size isn't a power of two, or greater than the | |||
10588 | // maximum alignment where we promote atomics, we know it is not lock-free | |||
10589 | // (at least not in the sense of atomic_is_lock_free). Otherwise, | |||
10590 | // the answer can only be determined at runtime; for example, 16-byte | |||
10591 | // atomics have lock-free implementations on some, but not all, | |||
10592 | // x86-64 processors. | |||
10593 | ||||
10594 | // Check power-of-two. | |||
10595 | CharUnits Size = CharUnits::fromQuantity(SizeVal.getZExtValue()); | |||
10596 | if (Size.isPowerOfTwo()) { | |||
10597 | // Check against inlining width. | |||
10598 | unsigned InlineWidthBits = | |||
10599 | Info.Ctx.getTargetInfo().getMaxAtomicInlineWidth(); | |||
10600 | if (Size <= Info.Ctx.toCharUnitsFromBits(InlineWidthBits)) { | |||
10601 | if (BuiltinOp == Builtin::BI__c11_atomic_is_lock_free || | |||
10602 | Size == CharUnits::One() || | |||
10603 | E->getArg(1)->isNullPointerConstant(Info.Ctx, | |||
10604 | Expr::NPC_NeverValueDependent)) | |||
10605 | // OK, we will inline appropriately-aligned operations of this size, | |||
10606 | // and _Atomic(T) is appropriately-aligned. | |||
10607 | return Success(1, E); | |||
10608 | ||||
10609 | QualType PointeeType = E->getArg(1)->IgnoreImpCasts()->getType()-> | |||
10610 | castAs<PointerType>()->getPointeeType(); | |||
10611 | if (!PointeeType->isIncompleteType() && | |||
10612 | Info.Ctx.getTypeAlignInChars(PointeeType) >= Size) { | |||
10613 | // OK, we will inline operations on this object. | |||
10614 | return Success(1, E); | |||
10615 | } | |||
10616 | } | |||
10617 | } | |||
10618 | ||||
10619 | return BuiltinOp == Builtin::BI__atomic_always_lock_free ? | |||
10620 | Success(0, E) : Error(E); | |||
10621 | } | |||
10622 | case Builtin::BIomp_is_initial_device: | |||
10623 | // We can decide statically which value the runtime would return if called. | |||
10624 | return Success(Info.getLangOpts().OpenMPIsDevice ? 0 : 1, E); | |||
10625 | case Builtin::BI__builtin_add_overflow: | |||
10626 | case Builtin::BI__builtin_sub_overflow: | |||
10627 | case Builtin::BI__builtin_mul_overflow: | |||
10628 | case Builtin::BI__builtin_sadd_overflow: | |||
10629 | case Builtin::BI__builtin_uadd_overflow: | |||
10630 | case Builtin::BI__builtin_uaddl_overflow: | |||
10631 | case Builtin::BI__builtin_uaddll_overflow: | |||
10632 | case Builtin::BI__builtin_usub_overflow: | |||
10633 | case Builtin::BI__builtin_usubl_overflow: | |||
10634 | case Builtin::BI__builtin_usubll_overflow: | |||
10635 | case Builtin::BI__builtin_umul_overflow: | |||
10636 | case Builtin::BI__builtin_umull_overflow: | |||
10637 | case Builtin::BI__builtin_umulll_overflow: | |||
10638 | case Builtin::BI__builtin_saddl_overflow: | |||
10639 | case Builtin::BI__builtin_saddll_overflow: | |||
10640 | case Builtin::BI__builtin_ssub_overflow: | |||
10641 | case Builtin::BI__builtin_ssubl_overflow: | |||
10642 | case Builtin::BI__builtin_ssubll_overflow: | |||
10643 | case Builtin::BI__builtin_smul_overflow: | |||
10644 | case Builtin::BI__builtin_smull_overflow: | |||
10645 | case Builtin::BI__builtin_smulll_overflow: { | |||
10646 | LValue ResultLValue; | |||
10647 | APSInt LHS, RHS; | |||
10648 | ||||
10649 | QualType ResultType = E->getArg(2)->getType()->getPointeeType(); | |||
10650 | if (!EvaluateInteger(E->getArg(0), LHS, Info) || | |||
10651 | !EvaluateInteger(E->getArg(1), RHS, Info) || | |||
10652 | !EvaluatePointer(E->getArg(2), ResultLValue, Info)) | |||
10653 | return false; | |||
10654 | ||||
10655 | APSInt Result; | |||
10656 | bool DidOverflow = false; | |||
10657 | ||||
10658 | // If the types don't have to match, enlarge all 3 to the largest of them. | |||
10659 | if (BuiltinOp == Builtin::BI__builtin_add_overflow || | |||
10660 | BuiltinOp == Builtin::BI__builtin_sub_overflow || | |||
10661 | BuiltinOp == Builtin::BI__builtin_mul_overflow) { | |||
10662 | bool IsSigned = LHS.isSigned() || RHS.isSigned() || | |||
10663 | ResultType->isSignedIntegerOrEnumerationType(); | |||
10664 | bool AllSigned = LHS.isSigned() && RHS.isSigned() && | |||
10665 | ResultType->isSignedIntegerOrEnumerationType(); | |||
10666 | uint64_t LHSSize = LHS.getBitWidth(); | |||
10667 | uint64_t RHSSize = RHS.getBitWidth(); | |||
10668 | uint64_t ResultSize = Info.Ctx.getTypeSize(ResultType); | |||
10669 | uint64_t MaxBits = std::max(std::max(LHSSize, RHSSize), ResultSize); | |||
10670 | ||||
10671 | // Add an additional bit if the signedness isn't uniformly agreed to. We | |||
10672 | // could do this ONLY if there is a signed and an unsigned that both have | |||
10673 | // MaxBits, but the code to check that is pretty nasty. The issue will be | |||
10674 | // caught in the shrink-to-result later anyway. | |||
10675 | if (IsSigned && !AllSigned) | |||
10676 | ++MaxBits; | |||
10677 | ||||
10678 | LHS = APSInt(LHS.extOrTrunc(MaxBits), !IsSigned); | |||
10679 | RHS = APSInt(RHS.extOrTrunc(MaxBits), !IsSigned); | |||
10680 | Result = APSInt(MaxBits, !IsSigned); | |||
10681 | } | |||
10682 | ||||
10683 | // Find largest int. | |||
10684 | switch (BuiltinOp) { | |||
10685 | default: | |||
10686 | llvm_unreachable("Invalid value for BuiltinOp")::llvm::llvm_unreachable_internal("Invalid value for BuiltinOp" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10686); | |||
10687 | case Builtin::BI__builtin_add_overflow: | |||
10688 | case Builtin::BI__builtin_sadd_overflow: | |||
10689 | case Builtin::BI__builtin_saddl_overflow: | |||
10690 | case Builtin::BI__builtin_saddll_overflow: | |||
10691 | case Builtin::BI__builtin_uadd_overflow: | |||
10692 | case Builtin::BI__builtin_uaddl_overflow: | |||
10693 | case Builtin::BI__builtin_uaddll_overflow: | |||
10694 | Result = LHS.isSigned() ? LHS.sadd_ov(RHS, DidOverflow) | |||
10695 | : LHS.uadd_ov(RHS, DidOverflow); | |||
10696 | break; | |||
10697 | case Builtin::BI__builtin_sub_overflow: | |||
10698 | case Builtin::BI__builtin_ssub_overflow: | |||
10699 | case Builtin::BI__builtin_ssubl_overflow: | |||
10700 | case Builtin::BI__builtin_ssubll_overflow: | |||
10701 | case Builtin::BI__builtin_usub_overflow: | |||
10702 | case Builtin::BI__builtin_usubl_overflow: | |||
10703 | case Builtin::BI__builtin_usubll_overflow: | |||
10704 | Result = LHS.isSigned() ? LHS.ssub_ov(RHS, DidOverflow) | |||
10705 | : LHS.usub_ov(RHS, DidOverflow); | |||
10706 | break; | |||
10707 | case Builtin::BI__builtin_mul_overflow: | |||
10708 | case Builtin::BI__builtin_smul_overflow: | |||
10709 | case Builtin::BI__builtin_smull_overflow: | |||
10710 | case Builtin::BI__builtin_smulll_overflow: | |||
10711 | case Builtin::BI__builtin_umul_overflow: | |||
10712 | case Builtin::BI__builtin_umull_overflow: | |||
10713 | case Builtin::BI__builtin_umulll_overflow: | |||
10714 | Result = LHS.isSigned() ? LHS.smul_ov(RHS, DidOverflow) | |||
10715 | : LHS.umul_ov(RHS, DidOverflow); | |||
10716 | break; | |||
10717 | } | |||
10718 | ||||
10719 | // In the case where multiple sizes are allowed, truncate and see if | |||
10720 | // the values are the same. | |||
10721 | if (BuiltinOp == Builtin::BI__builtin_add_overflow || | |||
10722 | BuiltinOp == Builtin::BI__builtin_sub_overflow || | |||
10723 | BuiltinOp == Builtin::BI__builtin_mul_overflow) { | |||
10724 | // APSInt doesn't have a TruncOrSelf, so we use extOrTrunc instead, | |||
10725 | // since it will give us the behavior of a TruncOrSelf in the case where | |||
10726 | // its parameter <= its size. We previously set Result to be at least the | |||
10727 | // type-size of the result, so getTypeSize(ResultType) <= Result.BitWidth | |||
10728 | // will work exactly like TruncOrSelf. | |||
10729 | APSInt Temp = Result.extOrTrunc(Info.Ctx.getTypeSize(ResultType)); | |||
10730 | Temp.setIsSigned(ResultType->isSignedIntegerOrEnumerationType()); | |||
10731 | ||||
10732 | if (!APSInt::isSameValue(Temp, Result)) | |||
10733 | DidOverflow = true; | |||
10734 | Result = Temp; | |||
10735 | } | |||
10736 | ||||
10737 | APValue APV{Result}; | |||
10738 | if (!handleAssignment(Info, E, ResultLValue, ResultType, APV)) | |||
10739 | return false; | |||
10740 | return Success(DidOverflow, E); | |||
10741 | } | |||
10742 | } | |||
10743 | } | |||
10744 | ||||
10745 | /// Determine whether this is a pointer past the end of the complete | |||
10746 | /// object referred to by the lvalue. | |||
10747 | static bool isOnePastTheEndOfCompleteObject(const ASTContext &Ctx, | |||
10748 | const LValue &LV) { | |||
10749 | // A null pointer can be viewed as being "past the end" but we don't | |||
10750 | // choose to look at it that way here. | |||
10751 | if (!LV.getLValueBase()) | |||
10752 | return false; | |||
10753 | ||||
10754 | // If the designator is valid and refers to a subobject, we're not pointing | |||
10755 | // past the end. | |||
10756 | if (!LV.getLValueDesignator().Invalid && | |||
10757 | !LV.getLValueDesignator().isOnePastTheEnd()) | |||
10758 | return false; | |||
10759 | ||||
10760 | // A pointer to an incomplete type might be past-the-end if the type's size is | |||
10761 | // zero. We cannot tell because the type is incomplete. | |||
10762 | QualType Ty = getType(LV.getLValueBase()); | |||
10763 | if (Ty->isIncompleteType()) | |||
10764 | return true; | |||
10765 | ||||
10766 | // We're a past-the-end pointer if we point to the byte after the object, | |||
10767 | // no matter what our type or path is. | |||
10768 | auto Size = Ctx.getTypeSizeInChars(Ty); | |||
10769 | return LV.getLValueOffset() == Size; | |||
10770 | } | |||
10771 | ||||
10772 | namespace { | |||
10773 | ||||
10774 | /// Data recursive integer evaluator of certain binary operators. | |||
10775 | /// | |||
10776 | /// We use a data recursive algorithm for binary operators so that we are able | |||
10777 | /// to handle extreme cases of chained binary operators without causing stack | |||
10778 | /// overflow. | |||
10779 | class DataRecursiveIntBinOpEvaluator { | |||
10780 | struct EvalResult { | |||
10781 | APValue Val; | |||
10782 | bool Failed; | |||
10783 | ||||
10784 | EvalResult() : Failed(false) { } | |||
10785 | ||||
10786 | void swap(EvalResult &RHS) { | |||
10787 | Val.swap(RHS.Val); | |||
10788 | Failed = RHS.Failed; | |||
10789 | RHS.Failed = false; | |||
10790 | } | |||
10791 | }; | |||
10792 | ||||
10793 | struct Job { | |||
10794 | const Expr *E; | |||
10795 | EvalResult LHSResult; // meaningful only for binary operator expression. | |||
10796 | enum { AnyExprKind, BinOpKind, BinOpVisitedLHSKind } Kind; | |||
10797 | ||||
10798 | Job() = default; | |||
10799 | Job(Job &&) = default; | |||
10800 | ||||
10801 | void startSpeculativeEval(EvalInfo &Info) { | |||
10802 | SpecEvalRAII = SpeculativeEvaluationRAII(Info); | |||
10803 | } | |||
10804 | ||||
10805 | private: | |||
10806 | SpeculativeEvaluationRAII SpecEvalRAII; | |||
10807 | }; | |||
10808 | ||||
10809 | SmallVector<Job, 16> Queue; | |||
10810 | ||||
10811 | IntExprEvaluator &IntEval; | |||
10812 | EvalInfo &Info; | |||
10813 | APValue &FinalResult; | |||
10814 | ||||
10815 | public: | |||
10816 | DataRecursiveIntBinOpEvaluator(IntExprEvaluator &IntEval, APValue &Result) | |||
10817 | : IntEval(IntEval), Info(IntEval.getEvalInfo()), FinalResult(Result) { } | |||
10818 | ||||
10819 | /// True if \param E is a binary operator that we are going to handle | |||
10820 | /// data recursively. | |||
10821 | /// We handle binary operators that are comma, logical, or that have operands | |||
10822 | /// with integral or enumeration type. | |||
10823 | static bool shouldEnqueue(const BinaryOperator *E) { | |||
10824 | return E->getOpcode() == BO_Comma || E->isLogicalOp() || | |||
10825 | (E->isRValue() && E->getType()->isIntegralOrEnumerationType() && | |||
10826 | E->getLHS()->getType()->isIntegralOrEnumerationType() && | |||
10827 | E->getRHS()->getType()->isIntegralOrEnumerationType()); | |||
10828 | } | |||
10829 | ||||
10830 | bool Traverse(const BinaryOperator *E) { | |||
10831 | enqueue(E); | |||
10832 | EvalResult PrevResult; | |||
10833 | while (!Queue.empty()) | |||
10834 | process(PrevResult); | |||
10835 | ||||
10836 | if (PrevResult.Failed) return false; | |||
10837 | ||||
10838 | FinalResult.swap(PrevResult.Val); | |||
10839 | return true; | |||
10840 | } | |||
10841 | ||||
10842 | private: | |||
10843 | bool Success(uint64_t Value, const Expr *E, APValue &Result) { | |||
10844 | return IntEval.Success(Value, E, Result); | |||
10845 | } | |||
10846 | bool Success(const APSInt &Value, const Expr *E, APValue &Result) { | |||
10847 | return IntEval.Success(Value, E, Result); | |||
10848 | } | |||
10849 | bool Error(const Expr *E) { | |||
10850 | return IntEval.Error(E); | |||
10851 | } | |||
10852 | bool Error(const Expr *E, diag::kind D) { | |||
10853 | return IntEval.Error(E, D); | |||
10854 | } | |||
10855 | ||||
10856 | OptionalDiagnostic CCEDiag(const Expr *E, diag::kind D) { | |||
10857 | return Info.CCEDiag(E, D); | |||
10858 | } | |||
10859 | ||||
10860 | // Returns true if visiting the RHS is necessary, false otherwise. | |||
10861 | bool VisitBinOpLHSOnly(EvalResult &LHSResult, const BinaryOperator *E, | |||
10862 | bool &SuppressRHSDiags); | |||
10863 | ||||
10864 | bool VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult, | |||
10865 | const BinaryOperator *E, APValue &Result); | |||
10866 | ||||
10867 | void EvaluateExpr(const Expr *E, EvalResult &Result) { | |||
10868 | Result.Failed = !Evaluate(Result.Val, Info, E); | |||
10869 | if (Result.Failed) | |||
10870 | Result.Val = APValue(); | |||
10871 | } | |||
10872 | ||||
10873 | void process(EvalResult &Result); | |||
10874 | ||||
10875 | void enqueue(const Expr *E) { | |||
10876 | E = E->IgnoreParens(); | |||
10877 | Queue.resize(Queue.size()+1); | |||
10878 | Queue.back().E = E; | |||
10879 | Queue.back().Kind = Job::AnyExprKind; | |||
10880 | } | |||
10881 | }; | |||
10882 | ||||
10883 | } | |||
10884 | ||||
10885 | bool DataRecursiveIntBinOpEvaluator:: | |||
10886 | VisitBinOpLHSOnly(EvalResult &LHSResult, const BinaryOperator *E, | |||
10887 | bool &SuppressRHSDiags) { | |||
10888 | if (E->getOpcode() == BO_Comma) { | |||
10889 | // Ignore LHS but note if we could not evaluate it. | |||
10890 | if (LHSResult.Failed) | |||
10891 | return Info.noteSideEffect(); | |||
10892 | return true; | |||
10893 | } | |||
10894 | ||||
10895 | if (E->isLogicalOp()) { | |||
10896 | bool LHSAsBool; | |||
10897 | if (!LHSResult.Failed && HandleConversionToBool(LHSResult.Val, LHSAsBool)) { | |||
10898 | // We were able to evaluate the LHS, see if we can get away with not | |||
10899 | // evaluating the RHS: 0 && X -> 0, 1 || X -> 1 | |||
10900 | if (LHSAsBool == (E->getOpcode() == BO_LOr)) { | |||
10901 | Success(LHSAsBool, E, LHSResult.Val); | |||
10902 | return false; // Ignore RHS | |||
10903 | } | |||
10904 | } else { | |||
10905 | LHSResult.Failed = true; | |||
10906 | ||||
10907 | // Since we weren't able to evaluate the left hand side, it | |||
10908 | // might have had side effects. | |||
10909 | if (!Info.noteSideEffect()) | |||
10910 | return false; | |||
10911 | ||||
10912 | // We can't evaluate the LHS; however, sometimes the result | |||
10913 | // is determined by the RHS: X && 0 -> 0, X || 1 -> 1. | |||
10914 | // Don't ignore RHS and suppress diagnostics from this arm. | |||
10915 | SuppressRHSDiags = true; | |||
10916 | } | |||
10917 | ||||
10918 | return true; | |||
10919 | } | |||
10920 | ||||
10921 | assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&((E->getLHS()->getType()->isIntegralOrEnumerationType () && E->getRHS()->getType()->isIntegralOrEnumerationType ()) ? static_cast<void> (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10922, __PRETTY_FUNCTION__)) | |||
10922 | E->getRHS()->getType()->isIntegralOrEnumerationType())((E->getLHS()->getType()->isIntegralOrEnumerationType () && E->getRHS()->getType()->isIntegralOrEnumerationType ()) ? static_cast<void> (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10922, __PRETTY_FUNCTION__)); | |||
10923 | ||||
10924 | if (LHSResult.Failed && !Info.noteFailure()) | |||
10925 | return false; // Ignore RHS; | |||
10926 | ||||
10927 | return true; | |||
10928 | } | |||
10929 | ||||
10930 | static void addOrSubLValueAsInteger(APValue &LVal, const APSInt &Index, | |||
10931 | bool IsSub) { | |||
10932 | // Compute the new offset in the appropriate width, wrapping at 64 bits. | |||
10933 | // FIXME: When compiling for a 32-bit target, we should use 32-bit | |||
10934 | // offsets. | |||
10935 | assert(!LVal.hasLValuePath() && "have designator for integer lvalue")((!LVal.hasLValuePath() && "have designator for integer lvalue" ) ? static_cast<void> (0) : __assert_fail ("!LVal.hasLValuePath() && \"have designator for integer lvalue\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10935, __PRETTY_FUNCTION__)); | |||
10936 | CharUnits &Offset = LVal.getLValueOffset(); | |||
10937 | uint64_t Offset64 = Offset.getQuantity(); | |||
10938 | uint64_t Index64 = Index.extOrTrunc(64).getZExtValue(); | |||
10939 | Offset = CharUnits::fromQuantity(IsSub ? Offset64 - Index64 | |||
10940 | : Offset64 + Index64); | |||
10941 | } | |||
10942 | ||||
10943 | bool DataRecursiveIntBinOpEvaluator:: | |||
10944 | VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult, | |||
10945 | const BinaryOperator *E, APValue &Result) { | |||
10946 | if (E->getOpcode() == BO_Comma) { | |||
10947 | if (RHSResult.Failed) | |||
10948 | return false; | |||
10949 | Result = RHSResult.Val; | |||
10950 | return true; | |||
10951 | } | |||
10952 | ||||
10953 | if (E->isLogicalOp()) { | |||
10954 | bool lhsResult, rhsResult; | |||
10955 | bool LHSIsOK = HandleConversionToBool(LHSResult.Val, lhsResult); | |||
10956 | bool RHSIsOK = HandleConversionToBool(RHSResult.Val, rhsResult); | |||
10957 | ||||
10958 | if (LHSIsOK) { | |||
10959 | if (RHSIsOK) { | |||
10960 | if (E->getOpcode() == BO_LOr) | |||
10961 | return Success(lhsResult || rhsResult, E, Result); | |||
10962 | else | |||
10963 | return Success(lhsResult && rhsResult, E, Result); | |||
10964 | } | |||
10965 | } else { | |||
10966 | if (RHSIsOK) { | |||
10967 | // We can't evaluate the LHS; however, sometimes the result | |||
10968 | // is determined by the RHS: X && 0 -> 0, X || 1 -> 1. | |||
10969 | if (rhsResult == (E->getOpcode() == BO_LOr)) | |||
10970 | return Success(rhsResult, E, Result); | |||
10971 | } | |||
10972 | } | |||
10973 | ||||
10974 | return false; | |||
10975 | } | |||
10976 | ||||
10977 | assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&((E->getLHS()->getType()->isIntegralOrEnumerationType () && E->getRHS()->getType()->isIntegralOrEnumerationType ()) ? static_cast<void> (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10978, __PRETTY_FUNCTION__)) | |||
10978 | E->getRHS()->getType()->isIntegralOrEnumerationType())((E->getLHS()->getType()->isIntegralOrEnumerationType () && E->getRHS()->getType()->isIntegralOrEnumerationType ()) ? static_cast<void> (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 10978, __PRETTY_FUNCTION__)); | |||
10979 | ||||
10980 | if (LHSResult.Failed || RHSResult.Failed) | |||
10981 | return false; | |||
10982 | ||||
10983 | const APValue &LHSVal = LHSResult.Val; | |||
10984 | const APValue &RHSVal = RHSResult.Val; | |||
10985 | ||||
10986 | // Handle cases like (unsigned long)&a + 4. | |||
10987 | if (E->isAdditiveOp() && LHSVal.isLValue() && RHSVal.isInt()) { | |||
10988 | Result = LHSVal; | |||
10989 | addOrSubLValueAsInteger(Result, RHSVal.getInt(), E->getOpcode() == BO_Sub); | |||
10990 | return true; | |||
10991 | } | |||
10992 | ||||
10993 | // Handle cases like 4 + (unsigned long)&a | |||
10994 | if (E->getOpcode() == BO_Add && | |||
10995 | RHSVal.isLValue() && LHSVal.isInt()) { | |||
10996 | Result = RHSVal; | |||
10997 | addOrSubLValueAsInteger(Result, LHSVal.getInt(), /*IsSub*/false); | |||
10998 | return true; | |||
10999 | } | |||
11000 | ||||
11001 | if (E->getOpcode() == BO_Sub && LHSVal.isLValue() && RHSVal.isLValue()) { | |||
11002 | // Handle (intptr_t)&&A - (intptr_t)&&B. | |||
11003 | if (!LHSVal.getLValueOffset().isZero() || | |||
11004 | !RHSVal.getLValueOffset().isZero()) | |||
11005 | return false; | |||
11006 | const Expr *LHSExpr = LHSVal.getLValueBase().dyn_cast<const Expr*>(); | |||
11007 | const Expr *RHSExpr = RHSVal.getLValueBase().dyn_cast<const Expr*>(); | |||
11008 | if (!LHSExpr || !RHSExpr) | |||
11009 | return false; | |||
11010 | const AddrLabelExpr *LHSAddrExpr = dyn_cast<AddrLabelExpr>(LHSExpr); | |||
11011 | const AddrLabelExpr *RHSAddrExpr = dyn_cast<AddrLabelExpr>(RHSExpr); | |||
11012 | if (!LHSAddrExpr || !RHSAddrExpr) | |||
11013 | return false; | |||
11014 | // Make sure both labels come from the same function. | |||
11015 | if (LHSAddrExpr->getLabel()->getDeclContext() != | |||
11016 | RHSAddrExpr->getLabel()->getDeclContext()) | |||
11017 | return false; | |||
11018 | Result = APValue(LHSAddrExpr, RHSAddrExpr); | |||
11019 | return true; | |||
11020 | } | |||
11021 | ||||
11022 | // All the remaining cases expect both operands to be an integer | |||
11023 | if (!LHSVal.isInt() || !RHSVal.isInt()) | |||
11024 | return Error(E); | |||
11025 | ||||
11026 | // Set up the width and signedness manually, in case it can't be deduced | |||
11027 | // from the operation we're performing. | |||
11028 | // FIXME: Don't do this in the cases where we can deduce it. | |||
11029 | APSInt Value(Info.Ctx.getIntWidth(E->getType()), | |||
11030 | E->getType()->isUnsignedIntegerOrEnumerationType()); | |||
11031 | if (!handleIntIntBinOp(Info, E, LHSVal.getInt(), E->getOpcode(), | |||
11032 | RHSVal.getInt(), Value)) | |||
11033 | return false; | |||
11034 | return Success(Value, E, Result); | |||
11035 | } | |||
11036 | ||||
11037 | void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) { | |||
11038 | Job &job = Queue.back(); | |||
11039 | ||||
11040 | switch (job.Kind) { | |||
11041 | case Job::AnyExprKind: { | |||
11042 | if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(job.E)) { | |||
11043 | if (shouldEnqueue(Bop)) { | |||
11044 | job.Kind = Job::BinOpKind; | |||
11045 | enqueue(Bop->getLHS()); | |||
11046 | return; | |||
11047 | } | |||
11048 | } | |||
11049 | ||||
11050 | EvaluateExpr(job.E, Result); | |||
11051 | Queue.pop_back(); | |||
11052 | return; | |||
11053 | } | |||
11054 | ||||
11055 | case Job::BinOpKind: { | |||
11056 | const BinaryOperator *Bop = cast<BinaryOperator>(job.E); | |||
11057 | bool SuppressRHSDiags = false; | |||
11058 | if (!VisitBinOpLHSOnly(Result, Bop, SuppressRHSDiags)) { | |||
11059 | Queue.pop_back(); | |||
11060 | return; | |||
11061 | } | |||
11062 | if (SuppressRHSDiags) | |||
11063 | job.startSpeculativeEval(Info); | |||
11064 | job.LHSResult.swap(Result); | |||
11065 | job.Kind = Job::BinOpVisitedLHSKind; | |||
11066 | enqueue(Bop->getRHS()); | |||
11067 | return; | |||
11068 | } | |||
11069 | ||||
11070 | case Job::BinOpVisitedLHSKind: { | |||
11071 | const BinaryOperator *Bop = cast<BinaryOperator>(job.E); | |||
11072 | EvalResult RHS; | |||
11073 | RHS.swap(Result); | |||
11074 | Result.Failed = !VisitBinOp(job.LHSResult, RHS, Bop, Result.Val); | |||
11075 | Queue.pop_back(); | |||
11076 | return; | |||
11077 | } | |||
11078 | } | |||
11079 | ||||
11080 | llvm_unreachable("Invalid Job::Kind!")::llvm::llvm_unreachable_internal("Invalid Job::Kind!", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11080); | |||
11081 | } | |||
11082 | ||||
11083 | namespace { | |||
11084 | /// Used when we determine that we should fail, but can keep evaluating prior to | |||
11085 | /// noting that we had a failure. | |||
11086 | class DelayedNoteFailureRAII { | |||
11087 | EvalInfo &Info; | |||
11088 | bool NoteFailure; | |||
11089 | ||||
11090 | public: | |||
11091 | DelayedNoteFailureRAII(EvalInfo &Info, bool NoteFailure = true) | |||
11092 | : Info(Info), NoteFailure(NoteFailure) {} | |||
11093 | ~DelayedNoteFailureRAII() { | |||
11094 | if (NoteFailure) { | |||
11095 | bool ContinueAfterFailure = Info.noteFailure(); | |||
11096 | (void)ContinueAfterFailure; | |||
11097 | assert(ContinueAfterFailure &&((ContinueAfterFailure && "Shouldn't have kept evaluating on failure." ) ? static_cast<void> (0) : __assert_fail ("ContinueAfterFailure && \"Shouldn't have kept evaluating on failure.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11098, __PRETTY_FUNCTION__)) | |||
11098 | "Shouldn't have kept evaluating on failure.")((ContinueAfterFailure && "Shouldn't have kept evaluating on failure." ) ? static_cast<void> (0) : __assert_fail ("ContinueAfterFailure && \"Shouldn't have kept evaluating on failure.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11098, __PRETTY_FUNCTION__)); | |||
11099 | } | |||
11100 | } | |||
11101 | }; | |||
11102 | } | |||
11103 | ||||
11104 | template <class SuccessCB, class AfterCB> | |||
11105 | static bool | |||
11106 | EvaluateComparisonBinaryOperator(EvalInfo &Info, const BinaryOperator *E, | |||
11107 | SuccessCB &&Success, AfterCB &&DoAfter) { | |||
11108 | assert(E->isComparisonOp() && "expected comparison operator")((E->isComparisonOp() && "expected comparison operator" ) ? static_cast<void> (0) : __assert_fail ("E->isComparisonOp() && \"expected comparison operator\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11108, __PRETTY_FUNCTION__)); | |||
11109 | assert((E->getOpcode() == BO_Cmp ||(((E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType ()) && "unsupported binary expression evaluation") ? static_cast <void> (0) : __assert_fail ("(E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11111, __PRETTY_FUNCTION__)) | |||
11110 | E->getType()->isIntegralOrEnumerationType()) &&(((E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType ()) && "unsupported binary expression evaluation") ? static_cast <void> (0) : __assert_fail ("(E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11111, __PRETTY_FUNCTION__)) | |||
11111 | "unsupported binary expression evaluation")(((E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType ()) && "unsupported binary expression evaluation") ? static_cast <void> (0) : __assert_fail ("(E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11111, __PRETTY_FUNCTION__)); | |||
11112 | auto Error = [&](const Expr *E) { | |||
11113 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
11114 | return false; | |||
11115 | }; | |||
11116 | ||||
11117 | using CCR = ComparisonCategoryResult; | |||
11118 | bool IsRelational = E->isRelationalOp(); | |||
11119 | bool IsEquality = E->isEqualityOp(); | |||
11120 | if (E->getOpcode() == BO_Cmp) { | |||
11121 | const ComparisonCategoryInfo &CmpInfo = | |||
11122 | Info.Ctx.CompCategories.getInfoForType(E->getType()); | |||
11123 | IsRelational = CmpInfo.isOrdered(); | |||
11124 | IsEquality = CmpInfo.isEquality(); | |||
11125 | } | |||
11126 | ||||
11127 | QualType LHSTy = E->getLHS()->getType(); | |||
11128 | QualType RHSTy = E->getRHS()->getType(); | |||
11129 | ||||
11130 | if (LHSTy->isIntegralOrEnumerationType() && | |||
11131 | RHSTy->isIntegralOrEnumerationType()) { | |||
11132 | APSInt LHS, RHS; | |||
11133 | bool LHSOK = EvaluateInteger(E->getLHS(), LHS, Info); | |||
11134 | if (!LHSOK && !Info.noteFailure()) | |||
11135 | return false; | |||
11136 | if (!EvaluateInteger(E->getRHS(), RHS, Info) || !LHSOK) | |||
11137 | return false; | |||
11138 | if (LHS < RHS) | |||
11139 | return Success(CCR::Less, E); | |||
11140 | if (LHS > RHS) | |||
11141 | return Success(CCR::Greater, E); | |||
11142 | return Success(CCR::Equal, E); | |||
11143 | } | |||
11144 | ||||
11145 | if (LHSTy->isFixedPointType() || RHSTy->isFixedPointType()) { | |||
11146 | APFixedPoint LHSFX(Info.Ctx.getFixedPointSemantics(LHSTy)); | |||
11147 | APFixedPoint RHSFX(Info.Ctx.getFixedPointSemantics(RHSTy)); | |||
11148 | ||||
11149 | bool LHSOK = EvaluateFixedPointOrInteger(E->getLHS(), LHSFX, Info); | |||
11150 | if (!LHSOK && !Info.noteFailure()) | |||
11151 | return false; | |||
11152 | if (!EvaluateFixedPointOrInteger(E->getRHS(), RHSFX, Info) || !LHSOK) | |||
11153 | return false; | |||
11154 | if (LHSFX < RHSFX) | |||
11155 | return Success(CCR::Less, E); | |||
11156 | if (LHSFX > RHSFX) | |||
11157 | return Success(CCR::Greater, E); | |||
11158 | return Success(CCR::Equal, E); | |||
11159 | } | |||
11160 | ||||
11161 | if (LHSTy->isAnyComplexType() || RHSTy->isAnyComplexType()) { | |||
11162 | ComplexValue LHS, RHS; | |||
11163 | bool LHSOK; | |||
11164 | if (E->isAssignmentOp()) { | |||
11165 | LValue LV; | |||
11166 | EvaluateLValue(E->getLHS(), LV, Info); | |||
11167 | LHSOK = false; | |||
11168 | } else if (LHSTy->isRealFloatingType()) { | |||
11169 | LHSOK = EvaluateFloat(E->getLHS(), LHS.FloatReal, Info); | |||
11170 | if (LHSOK) { | |||
11171 | LHS.makeComplexFloat(); | |||
11172 | LHS.FloatImag = APFloat(LHS.FloatReal.getSemantics()); | |||
11173 | } | |||
11174 | } else { | |||
11175 | LHSOK = EvaluateComplex(E->getLHS(), LHS, Info); | |||
11176 | } | |||
11177 | if (!LHSOK && !Info.noteFailure()) | |||
11178 | return false; | |||
11179 | ||||
11180 | if (E->getRHS()->getType()->isRealFloatingType()) { | |||
11181 | if (!EvaluateFloat(E->getRHS(), RHS.FloatReal, Info) || !LHSOK) | |||
11182 | return false; | |||
11183 | RHS.makeComplexFloat(); | |||
11184 | RHS.FloatImag = APFloat(RHS.FloatReal.getSemantics()); | |||
11185 | } else if (!EvaluateComplex(E->getRHS(), RHS, Info) || !LHSOK) | |||
11186 | return false; | |||
11187 | ||||
11188 | if (LHS.isComplexFloat()) { | |||
11189 | APFloat::cmpResult CR_r = | |||
11190 | LHS.getComplexFloatReal().compare(RHS.getComplexFloatReal()); | |||
11191 | APFloat::cmpResult CR_i = | |||
11192 | LHS.getComplexFloatImag().compare(RHS.getComplexFloatImag()); | |||
11193 | bool IsEqual = CR_r == APFloat::cmpEqual && CR_i == APFloat::cmpEqual; | |||
11194 | return Success(IsEqual ? CCR::Equal : CCR::Nonequal, E); | |||
11195 | } else { | |||
11196 | assert(IsEquality && "invalid complex comparison")((IsEquality && "invalid complex comparison") ? static_cast <void> (0) : __assert_fail ("IsEquality && \"invalid complex comparison\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11196, __PRETTY_FUNCTION__)); | |||
11197 | bool IsEqual = LHS.getComplexIntReal() == RHS.getComplexIntReal() && | |||
11198 | LHS.getComplexIntImag() == RHS.getComplexIntImag(); | |||
11199 | return Success(IsEqual ? CCR::Equal : CCR::Nonequal, E); | |||
11200 | } | |||
11201 | } | |||
11202 | ||||
11203 | if (LHSTy->isRealFloatingType() && | |||
11204 | RHSTy->isRealFloatingType()) { | |||
11205 | APFloat RHS(0.0), LHS(0.0); | |||
11206 | ||||
11207 | bool LHSOK = EvaluateFloat(E->getRHS(), RHS, Info); | |||
11208 | if (!LHSOK && !Info.noteFailure()) | |||
11209 | return false; | |||
11210 | ||||
11211 | if (!EvaluateFloat(E->getLHS(), LHS, Info) || !LHSOK) | |||
11212 | return false; | |||
11213 | ||||
11214 | assert(E->isComparisonOp() && "Invalid binary operator!")((E->isComparisonOp() && "Invalid binary operator!" ) ? static_cast<void> (0) : __assert_fail ("E->isComparisonOp() && \"Invalid binary operator!\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11214, __PRETTY_FUNCTION__)); | |||
11215 | auto GetCmpRes = [&]() { | |||
11216 | switch (LHS.compare(RHS)) { | |||
11217 | case APFloat::cmpEqual: | |||
11218 | return CCR::Equal; | |||
11219 | case APFloat::cmpLessThan: | |||
11220 | return CCR::Less; | |||
11221 | case APFloat::cmpGreaterThan: | |||
11222 | return CCR::Greater; | |||
11223 | case APFloat::cmpUnordered: | |||
11224 | return CCR::Unordered; | |||
11225 | } | |||
11226 | llvm_unreachable("Unrecognised APFloat::cmpResult enum")::llvm::llvm_unreachable_internal("Unrecognised APFloat::cmpResult enum" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11226); | |||
11227 | }; | |||
11228 | return Success(GetCmpRes(), E); | |||
11229 | } | |||
11230 | ||||
11231 | if (LHSTy->isPointerType() && RHSTy->isPointerType()) { | |||
11232 | LValue LHSValue, RHSValue; | |||
11233 | ||||
11234 | bool LHSOK = EvaluatePointer(E->getLHS(), LHSValue, Info); | |||
11235 | if (!LHSOK && !Info.noteFailure()) | |||
11236 | return false; | |||
11237 | ||||
11238 | if (!EvaluatePointer(E->getRHS(), RHSValue, Info) || !LHSOK) | |||
11239 | return false; | |||
11240 | ||||
11241 | // Reject differing bases from the normal codepath; we special-case | |||
11242 | // comparisons to null. | |||
11243 | if (!HasSameBase(LHSValue, RHSValue)) { | |||
11244 | // Inequalities and subtractions between unrelated pointers have | |||
11245 | // unspecified or undefined behavior. | |||
11246 | if (!IsEquality) | |||
11247 | return Error(E); | |||
11248 | // A constant address may compare equal to the address of a symbol. | |||
11249 | // The one exception is that address of an object cannot compare equal | |||
11250 | // to a null pointer constant. | |||
11251 | if ((!LHSValue.Base && !LHSValue.Offset.isZero()) || | |||
11252 | (!RHSValue.Base && !RHSValue.Offset.isZero())) | |||
11253 | return Error(E); | |||
11254 | // It's implementation-defined whether distinct literals will have | |||
11255 | // distinct addresses. In clang, the result of such a comparison is | |||
11256 | // unspecified, so it is not a constant expression. However, we do know | |||
11257 | // that the address of a literal will be non-null. | |||
11258 | if ((IsLiteralLValue(LHSValue) || IsLiteralLValue(RHSValue)) && | |||
11259 | LHSValue.Base && RHSValue.Base) | |||
11260 | return Error(E); | |||
11261 | // We can't tell whether weak symbols will end up pointing to the same | |||
11262 | // object. | |||
11263 | if (IsWeakLValue(LHSValue) || IsWeakLValue(RHSValue)) | |||
11264 | return Error(E); | |||
11265 | // We can't compare the address of the start of one object with the | |||
11266 | // past-the-end address of another object, per C++ DR1652. | |||
11267 | if ((LHSValue.Base && LHSValue.Offset.isZero() && | |||
11268 | isOnePastTheEndOfCompleteObject(Info.Ctx, RHSValue)) || | |||
11269 | (RHSValue.Base && RHSValue.Offset.isZero() && | |||
11270 | isOnePastTheEndOfCompleteObject(Info.Ctx, LHSValue))) | |||
11271 | return Error(E); | |||
11272 | // We can't tell whether an object is at the same address as another | |||
11273 | // zero sized object. | |||
11274 | if ((RHSValue.Base && isZeroSized(LHSValue)) || | |||
11275 | (LHSValue.Base && isZeroSized(RHSValue))) | |||
11276 | return Error(E); | |||
11277 | return Success(CCR::Nonequal, E); | |||
11278 | } | |||
11279 | ||||
11280 | const CharUnits &LHSOffset = LHSValue.getLValueOffset(); | |||
11281 | const CharUnits &RHSOffset = RHSValue.getLValueOffset(); | |||
11282 | ||||
11283 | SubobjectDesignator &LHSDesignator = LHSValue.getLValueDesignator(); | |||
11284 | SubobjectDesignator &RHSDesignator = RHSValue.getLValueDesignator(); | |||
11285 | ||||
11286 | // C++11 [expr.rel]p3: | |||
11287 | // Pointers to void (after pointer conversions) can be compared, with a | |||
11288 | // result defined as follows: If both pointers represent the same | |||
11289 | // address or are both the null pointer value, the result is true if the | |||
11290 | // operator is <= or >= and false otherwise; otherwise the result is | |||
11291 | // unspecified. | |||
11292 | // We interpret this as applying to pointers to *cv* void. | |||
11293 | if (LHSTy->isVoidPointerType() && LHSOffset != RHSOffset && IsRelational) | |||
11294 | Info.CCEDiag(E, diag::note_constexpr_void_comparison); | |||
11295 | ||||
11296 | // C++11 [expr.rel]p2: | |||
11297 | // - If two pointers point to non-static data members of the same object, | |||
11298 | // or to subobjects or array elements fo such members, recursively, the | |||
11299 | // pointer to the later declared member compares greater provided the | |||
11300 | // two members have the same access control and provided their class is | |||
11301 | // not a union. | |||
11302 | // [...] | |||
11303 | // - Otherwise pointer comparisons are unspecified. | |||
11304 | if (!LHSDesignator.Invalid && !RHSDesignator.Invalid && IsRelational) { | |||
11305 | bool WasArrayIndex; | |||
11306 | unsigned Mismatch = FindDesignatorMismatch( | |||
11307 | getType(LHSValue.Base), LHSDesignator, RHSDesignator, WasArrayIndex); | |||
11308 | // At the point where the designators diverge, the comparison has a | |||
11309 | // specified value if: | |||
11310 | // - we are comparing array indices | |||
11311 | // - we are comparing fields of a union, or fields with the same access | |||
11312 | // Otherwise, the result is unspecified and thus the comparison is not a | |||
11313 | // constant expression. | |||
11314 | if (!WasArrayIndex && Mismatch < LHSDesignator.Entries.size() && | |||
11315 | Mismatch < RHSDesignator.Entries.size()) { | |||
11316 | const FieldDecl *LF = getAsField(LHSDesignator.Entries[Mismatch]); | |||
11317 | const FieldDecl *RF = getAsField(RHSDesignator.Entries[Mismatch]); | |||
11318 | if (!LF && !RF) | |||
11319 | Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_classes); | |||
11320 | else if (!LF) | |||
11321 | Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_field) | |||
11322 | << getAsBaseClass(LHSDesignator.Entries[Mismatch]) | |||
11323 | << RF->getParent() << RF; | |||
11324 | else if (!RF) | |||
11325 | Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_field) | |||
11326 | << getAsBaseClass(RHSDesignator.Entries[Mismatch]) | |||
11327 | << LF->getParent() << LF; | |||
11328 | else if (!LF->getParent()->isUnion() && | |||
11329 | LF->getAccess() != RF->getAccess()) | |||
11330 | Info.CCEDiag(E, | |||
11331 | diag::note_constexpr_pointer_comparison_differing_access) | |||
11332 | << LF << LF->getAccess() << RF << RF->getAccess() | |||
11333 | << LF->getParent(); | |||
11334 | } | |||
11335 | } | |||
11336 | ||||
11337 | // The comparison here must be unsigned, and performed with the same | |||
11338 | // width as the pointer. | |||
11339 | unsigned PtrSize = Info.Ctx.getTypeSize(LHSTy); | |||
11340 | uint64_t CompareLHS = LHSOffset.getQuantity(); | |||
11341 | uint64_t CompareRHS = RHSOffset.getQuantity(); | |||
11342 | assert(PtrSize <= 64 && "Unexpected pointer width")((PtrSize <= 64 && "Unexpected pointer width") ? static_cast <void> (0) : __assert_fail ("PtrSize <= 64 && \"Unexpected pointer width\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11342, __PRETTY_FUNCTION__)); | |||
11343 | uint64_t Mask = ~0ULL >> (64 - PtrSize); | |||
11344 | CompareLHS &= Mask; | |||
11345 | CompareRHS &= Mask; | |||
11346 | ||||
11347 | // If there is a base and this is a relational operator, we can only | |||
11348 | // compare pointers within the object in question; otherwise, the result | |||
11349 | // depends on where the object is located in memory. | |||
11350 | if (!LHSValue.Base.isNull() && IsRelational) { | |||
11351 | QualType BaseTy = getType(LHSValue.Base); | |||
11352 | if (BaseTy->isIncompleteType()) | |||
11353 | return Error(E); | |||
11354 | CharUnits Size = Info.Ctx.getTypeSizeInChars(BaseTy); | |||
11355 | uint64_t OffsetLimit = Size.getQuantity(); | |||
11356 | if (CompareLHS > OffsetLimit || CompareRHS > OffsetLimit) | |||
11357 | return Error(E); | |||
11358 | } | |||
11359 | ||||
11360 | if (CompareLHS < CompareRHS) | |||
11361 | return Success(CCR::Less, E); | |||
11362 | if (CompareLHS > CompareRHS) | |||
11363 | return Success(CCR::Greater, E); | |||
11364 | return Success(CCR::Equal, E); | |||
11365 | } | |||
11366 | ||||
11367 | if (LHSTy->isMemberPointerType()) { | |||
11368 | assert(IsEquality && "unexpected member pointer operation")((IsEquality && "unexpected member pointer operation" ) ? static_cast<void> (0) : __assert_fail ("IsEquality && \"unexpected member pointer operation\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11368, __PRETTY_FUNCTION__)); | |||
11369 | assert(RHSTy->isMemberPointerType() && "invalid comparison")((RHSTy->isMemberPointerType() && "invalid comparison" ) ? static_cast<void> (0) : __assert_fail ("RHSTy->isMemberPointerType() && \"invalid comparison\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11369, __PRETTY_FUNCTION__)); | |||
11370 | ||||
11371 | MemberPtr LHSValue, RHSValue; | |||
11372 | ||||
11373 | bool LHSOK = EvaluateMemberPointer(E->getLHS(), LHSValue, Info); | |||
11374 | if (!LHSOK && !Info.noteFailure()) | |||
11375 | return false; | |||
11376 | ||||
11377 | if (!EvaluateMemberPointer(E->getRHS(), RHSValue, Info) || !LHSOK) | |||
11378 | return false; | |||
11379 | ||||
11380 | // C++11 [expr.eq]p2: | |||
11381 | // If both operands are null, they compare equal. Otherwise if only one is | |||
11382 | // null, they compare unequal. | |||
11383 | if (!LHSValue.getDecl() || !RHSValue.getDecl()) { | |||
11384 | bool Equal = !LHSValue.getDecl() && !RHSValue.getDecl(); | |||
11385 | return Success(Equal ? CCR::Equal : CCR::Nonequal, E); | |||
11386 | } | |||
11387 | ||||
11388 | // Otherwise if either is a pointer to a virtual member function, the | |||
11389 | // result is unspecified. | |||
11390 | if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(LHSValue.getDecl())) | |||
11391 | if (MD->isVirtual()) | |||
11392 | Info.CCEDiag(E, diag::note_constexpr_compare_virtual_mem_ptr) << MD; | |||
11393 | if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(RHSValue.getDecl())) | |||
11394 | if (MD->isVirtual()) | |||
11395 | Info.CCEDiag(E, diag::note_constexpr_compare_virtual_mem_ptr) << MD; | |||
11396 | ||||
11397 | // Otherwise they compare equal if and only if they would refer to the | |||
11398 | // same member of the same most derived object or the same subobject if | |||
11399 | // they were dereferenced with a hypothetical object of the associated | |||
11400 | // class type. | |||
11401 | bool Equal = LHSValue == RHSValue; | |||
11402 | return Success(Equal ? CCR::Equal : CCR::Nonequal, E); | |||
11403 | } | |||
11404 | ||||
11405 | if (LHSTy->isNullPtrType()) { | |||
11406 | assert(E->isComparisonOp() && "unexpected nullptr operation")((E->isComparisonOp() && "unexpected nullptr operation" ) ? static_cast<void> (0) : __assert_fail ("E->isComparisonOp() && \"unexpected nullptr operation\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11406, __PRETTY_FUNCTION__)); | |||
11407 | assert(RHSTy->isNullPtrType() && "missing pointer conversion")((RHSTy->isNullPtrType() && "missing pointer conversion" ) ? static_cast<void> (0) : __assert_fail ("RHSTy->isNullPtrType() && \"missing pointer conversion\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11407, __PRETTY_FUNCTION__)); | |||
11408 | // C++11 [expr.rel]p4, [expr.eq]p3: If two operands of type std::nullptr_t | |||
11409 | // are compared, the result is true of the operator is <=, >= or ==, and | |||
11410 | // false otherwise. | |||
11411 | return Success(CCR::Equal, E); | |||
11412 | } | |||
11413 | ||||
11414 | return DoAfter(); | |||
11415 | } | |||
11416 | ||||
11417 | bool RecordExprEvaluator::VisitBinCmp(const BinaryOperator *E) { | |||
11418 | if (!CheckLiteralType(Info, E)) | |||
11419 | return false; | |||
11420 | ||||
11421 | auto OnSuccess = [&](ComparisonCategoryResult ResKind, | |||
11422 | const BinaryOperator *E) { | |||
11423 | // Evaluation succeeded. Lookup the information for the comparison category | |||
11424 | // type and fetch the VarDecl for the result. | |||
11425 | const ComparisonCategoryInfo &CmpInfo = | |||
11426 | Info.Ctx.CompCategories.getInfoForType(E->getType()); | |||
11427 | const VarDecl *VD = | |||
11428 | CmpInfo.getValueInfo(CmpInfo.makeWeakResult(ResKind))->VD; | |||
11429 | // Check and evaluate the result as a constant expression. | |||
11430 | LValue LV; | |||
11431 | LV.set(VD); | |||
11432 | if (!handleLValueToRValueConversion(Info, E, E->getType(), LV, Result)) | |||
11433 | return false; | |||
11434 | return CheckConstantExpression(Info, E->getExprLoc(), E->getType(), Result); | |||
11435 | }; | |||
11436 | return EvaluateComparisonBinaryOperator(Info, E, OnSuccess, [&]() { | |||
11437 | return ExprEvaluatorBaseTy::VisitBinCmp(E); | |||
11438 | }); | |||
11439 | } | |||
11440 | ||||
11441 | bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
11442 | // We don't call noteFailure immediately because the assignment happens after | |||
11443 | // we evaluate LHS and RHS. | |||
11444 | if (!Info.keepEvaluatingAfterFailure() && E->isAssignmentOp()) | |||
11445 | return Error(E); | |||
11446 | ||||
11447 | DelayedNoteFailureRAII MaybeNoteFailureLater(Info, E->isAssignmentOp()); | |||
11448 | if (DataRecursiveIntBinOpEvaluator::shouldEnqueue(E)) | |||
11449 | return DataRecursiveIntBinOpEvaluator(*this, Result).Traverse(E); | |||
11450 | ||||
11451 | assert((!E->getLHS()->getType()->isIntegralOrEnumerationType() ||(((!E->getLHS()->getType()->isIntegralOrEnumerationType () || !E->getRHS()->getType()->isIntegralOrEnumerationType ()) && "DataRecursiveIntBinOpEvaluator should have handled integral types" ) ? static_cast<void> (0) : __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() || !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11453, __PRETTY_FUNCTION__)) | |||
11452 | !E->getRHS()->getType()->isIntegralOrEnumerationType()) &&(((!E->getLHS()->getType()->isIntegralOrEnumerationType () || !E->getRHS()->getType()->isIntegralOrEnumerationType ()) && "DataRecursiveIntBinOpEvaluator should have handled integral types" ) ? static_cast<void> (0) : __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() || !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11453, __PRETTY_FUNCTION__)) | |||
11453 | "DataRecursiveIntBinOpEvaluator should have handled integral types")(((!E->getLHS()->getType()->isIntegralOrEnumerationType () || !E->getRHS()->getType()->isIntegralOrEnumerationType ()) && "DataRecursiveIntBinOpEvaluator should have handled integral types" ) ? static_cast<void> (0) : __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() || !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11453, __PRETTY_FUNCTION__)); | |||
11454 | ||||
11455 | if (E->isComparisonOp()) { | |||
11456 | // Evaluate builtin binary comparisons by evaluating them as C++2a three-way | |||
11457 | // comparisons and then translating the result. | |||
11458 | auto OnSuccess = [&](ComparisonCategoryResult ResKind, | |||
11459 | const BinaryOperator *E) { | |||
11460 | using CCR = ComparisonCategoryResult; | |||
11461 | bool IsEqual = ResKind == CCR::Equal, | |||
11462 | IsLess = ResKind == CCR::Less, | |||
11463 | IsGreater = ResKind == CCR::Greater; | |||
11464 | auto Op = E->getOpcode(); | |||
11465 | switch (Op) { | |||
11466 | default: | |||
11467 | llvm_unreachable("unsupported binary operator")::llvm::llvm_unreachable_internal("unsupported binary operator" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11467); | |||
11468 | case BO_EQ: | |||
11469 | case BO_NE: | |||
11470 | return Success(IsEqual == (Op == BO_EQ), E); | |||
11471 | case BO_LT: return Success(IsLess, E); | |||
11472 | case BO_GT: return Success(IsGreater, E); | |||
11473 | case BO_LE: return Success(IsEqual || IsLess, E); | |||
11474 | case BO_GE: return Success(IsEqual || IsGreater, E); | |||
11475 | } | |||
11476 | }; | |||
11477 | return EvaluateComparisonBinaryOperator(Info, E, OnSuccess, [&]() { | |||
11478 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
11479 | }); | |||
11480 | } | |||
11481 | ||||
11482 | QualType LHSTy = E->getLHS()->getType(); | |||
11483 | QualType RHSTy = E->getRHS()->getType(); | |||
11484 | ||||
11485 | if (LHSTy->isPointerType() && RHSTy->isPointerType() && | |||
11486 | E->getOpcode() == BO_Sub) { | |||
11487 | LValue LHSValue, RHSValue; | |||
11488 | ||||
11489 | bool LHSOK = EvaluatePointer(E->getLHS(), LHSValue, Info); | |||
11490 | if (!LHSOK && !Info.noteFailure()) | |||
11491 | return false; | |||
11492 | ||||
11493 | if (!EvaluatePointer(E->getRHS(), RHSValue, Info) || !LHSOK) | |||
11494 | return false; | |||
11495 | ||||
11496 | // Reject differing bases from the normal codepath; we special-case | |||
11497 | // comparisons to null. | |||
11498 | if (!HasSameBase(LHSValue, RHSValue)) { | |||
11499 | // Handle &&A - &&B. | |||
11500 | if (!LHSValue.Offset.isZero() || !RHSValue.Offset.isZero()) | |||
11501 | return Error(E); | |||
11502 | const Expr *LHSExpr = LHSValue.Base.dyn_cast<const Expr *>(); | |||
11503 | const Expr *RHSExpr = RHSValue.Base.dyn_cast<const Expr *>(); | |||
11504 | if (!LHSExpr || !RHSExpr) | |||
11505 | return Error(E); | |||
11506 | const AddrLabelExpr *LHSAddrExpr = dyn_cast<AddrLabelExpr>(LHSExpr); | |||
11507 | const AddrLabelExpr *RHSAddrExpr = dyn_cast<AddrLabelExpr>(RHSExpr); | |||
11508 | if (!LHSAddrExpr || !RHSAddrExpr) | |||
11509 | return Error(E); | |||
11510 | // Make sure both labels come from the same function. | |||
11511 | if (LHSAddrExpr->getLabel()->getDeclContext() != | |||
11512 | RHSAddrExpr->getLabel()->getDeclContext()) | |||
11513 | return Error(E); | |||
11514 | return Success(APValue(LHSAddrExpr, RHSAddrExpr), E); | |||
11515 | } | |||
11516 | const CharUnits &LHSOffset = LHSValue.getLValueOffset(); | |||
11517 | const CharUnits &RHSOffset = RHSValue.getLValueOffset(); | |||
11518 | ||||
11519 | SubobjectDesignator &LHSDesignator = LHSValue.getLValueDesignator(); | |||
11520 | SubobjectDesignator &RHSDesignator = RHSValue.getLValueDesignator(); | |||
11521 | ||||
11522 | // C++11 [expr.add]p6: | |||
11523 | // Unless both pointers point to elements of the same array object, or | |||
11524 | // one past the last element of the array object, the behavior is | |||
11525 | // undefined. | |||
11526 | if (!LHSDesignator.Invalid && !RHSDesignator.Invalid && | |||
11527 | !AreElementsOfSameArray(getType(LHSValue.Base), LHSDesignator, | |||
11528 | RHSDesignator)) | |||
11529 | Info.CCEDiag(E, diag::note_constexpr_pointer_subtraction_not_same_array); | |||
11530 | ||||
11531 | QualType Type = E->getLHS()->getType(); | |||
11532 | QualType ElementType = Type->getAs<PointerType>()->getPointeeType(); | |||
11533 | ||||
11534 | CharUnits ElementSize; | |||
11535 | if (!HandleSizeof(Info, E->getExprLoc(), ElementType, ElementSize)) | |||
11536 | return false; | |||
11537 | ||||
11538 | // As an extension, a type may have zero size (empty struct or union in | |||
11539 | // C, array of zero length). Pointer subtraction in such cases has | |||
11540 | // undefined behavior, so is not constant. | |||
11541 | if (ElementSize.isZero()) { | |||
11542 | Info.FFDiag(E, diag::note_constexpr_pointer_subtraction_zero_size) | |||
11543 | << ElementType; | |||
11544 | return false; | |||
11545 | } | |||
11546 | ||||
11547 | // FIXME: LLVM and GCC both compute LHSOffset - RHSOffset at runtime, | |||
11548 | // and produce incorrect results when it overflows. Such behavior | |||
11549 | // appears to be non-conforming, but is common, so perhaps we should | |||
11550 | // assume the standard intended for such cases to be undefined behavior | |||
11551 | // and check for them. | |||
11552 | ||||
11553 | // Compute (LHSOffset - RHSOffset) / Size carefully, checking for | |||
11554 | // overflow in the final conversion to ptrdiff_t. | |||
11555 | APSInt LHS(llvm::APInt(65, (int64_t)LHSOffset.getQuantity(), true), false); | |||
11556 | APSInt RHS(llvm::APInt(65, (int64_t)RHSOffset.getQuantity(), true), false); | |||
11557 | APSInt ElemSize(llvm::APInt(65, (int64_t)ElementSize.getQuantity(), true), | |||
11558 | false); | |||
11559 | APSInt TrueResult = (LHS - RHS) / ElemSize; | |||
11560 | APSInt Result = TrueResult.trunc(Info.Ctx.getIntWidth(E->getType())); | |||
11561 | ||||
11562 | if (Result.extend(65) != TrueResult && | |||
11563 | !HandleOverflow(Info, E, TrueResult, E->getType())) | |||
11564 | return false; | |||
11565 | return Success(Result, E); | |||
11566 | } | |||
11567 | ||||
11568 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
11569 | } | |||
11570 | ||||
11571 | /// VisitUnaryExprOrTypeTraitExpr - Evaluate a sizeof, alignof or vec_step with | |||
11572 | /// a result as the expression's type. | |||
11573 | bool IntExprEvaluator::VisitUnaryExprOrTypeTraitExpr( | |||
11574 | const UnaryExprOrTypeTraitExpr *E) { | |||
11575 | switch(E->getKind()) { | |||
11576 | case UETT_PreferredAlignOf: | |||
11577 | case UETT_AlignOf: { | |||
11578 | if (E->isArgumentType()) | |||
11579 | return Success(GetAlignOfType(Info, E->getArgumentType(), E->getKind()), | |||
11580 | E); | |||
11581 | else | |||
11582 | return Success(GetAlignOfExpr(Info, E->getArgumentExpr(), E->getKind()), | |||
11583 | E); | |||
11584 | } | |||
11585 | ||||
11586 | case UETT_VecStep: { | |||
11587 | QualType Ty = E->getTypeOfArgument(); | |||
11588 | ||||
11589 | if (Ty->isVectorType()) { | |||
11590 | unsigned n = Ty->castAs<VectorType>()->getNumElements(); | |||
11591 | ||||
11592 | // The vec_step built-in functions that take a 3-component | |||
11593 | // vector return 4. (OpenCL 1.1 spec 6.11.12) | |||
11594 | if (n == 3) | |||
11595 | n = 4; | |||
11596 | ||||
11597 | return Success(n, E); | |||
11598 | } else | |||
11599 | return Success(1, E); | |||
11600 | } | |||
11601 | ||||
11602 | case UETT_SizeOf: { | |||
11603 | QualType SrcTy = E->getTypeOfArgument(); | |||
11604 | // C++ [expr.sizeof]p2: "When applied to a reference or a reference type, | |||
11605 | // the result is the size of the referenced type." | |||
11606 | if (const ReferenceType *Ref = SrcTy->getAs<ReferenceType>()) | |||
11607 | SrcTy = Ref->getPointeeType(); | |||
11608 | ||||
11609 | CharUnits Sizeof; | |||
11610 | if (!HandleSizeof(Info, E->getExprLoc(), SrcTy, Sizeof)) | |||
11611 | return false; | |||
11612 | return Success(Sizeof, E); | |||
11613 | } | |||
11614 | case UETT_OpenMPRequiredSimdAlign: | |||
11615 | assert(E->isArgumentType())((E->isArgumentType()) ? static_cast<void> (0) : __assert_fail ("E->isArgumentType()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11615, __PRETTY_FUNCTION__)); | |||
11616 | return Success( | |||
11617 | Info.Ctx.toCharUnitsFromBits( | |||
11618 | Info.Ctx.getOpenMPDefaultSimdAlign(E->getArgumentType())) | |||
11619 | .getQuantity(), | |||
11620 | E); | |||
11621 | } | |||
11622 | ||||
11623 | llvm_unreachable("unknown expr/type trait")::llvm::llvm_unreachable_internal("unknown expr/type trait", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11623); | |||
11624 | } | |||
11625 | ||||
11626 | bool IntExprEvaluator::VisitOffsetOfExpr(const OffsetOfExpr *OOE) { | |||
11627 | CharUnits Result; | |||
11628 | unsigned n = OOE->getNumComponents(); | |||
11629 | if (n == 0) | |||
11630 | return Error(OOE); | |||
11631 | QualType CurrentType = OOE->getTypeSourceInfo()->getType(); | |||
11632 | for (unsigned i = 0; i != n; ++i) { | |||
11633 | OffsetOfNode ON = OOE->getComponent(i); | |||
11634 | switch (ON.getKind()) { | |||
11635 | case OffsetOfNode::Array: { | |||
11636 | const Expr *Idx = OOE->getIndexExpr(ON.getArrayExprIndex()); | |||
11637 | APSInt IdxResult; | |||
11638 | if (!EvaluateInteger(Idx, IdxResult, Info)) | |||
11639 | return false; | |||
11640 | const ArrayType *AT = Info.Ctx.getAsArrayType(CurrentType); | |||
11641 | if (!AT) | |||
11642 | return Error(OOE); | |||
11643 | CurrentType = AT->getElementType(); | |||
11644 | CharUnits ElementSize = Info.Ctx.getTypeSizeInChars(CurrentType); | |||
11645 | Result += IdxResult.getSExtValue() * ElementSize; | |||
11646 | break; | |||
11647 | } | |||
11648 | ||||
11649 | case OffsetOfNode::Field: { | |||
11650 | FieldDecl *MemberDecl = ON.getField(); | |||
11651 | const RecordType *RT = CurrentType->getAs<RecordType>(); | |||
11652 | if (!RT) | |||
11653 | return Error(OOE); | |||
11654 | RecordDecl *RD = RT->getDecl(); | |||
11655 | if (RD->isInvalidDecl()) return false; | |||
11656 | const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD); | |||
11657 | unsigned i = MemberDecl->getFieldIndex(); | |||
11658 | assert(i < RL.getFieldCount() && "offsetof field in wrong type")((i < RL.getFieldCount() && "offsetof field in wrong type" ) ? static_cast<void> (0) : __assert_fail ("i < RL.getFieldCount() && \"offsetof field in wrong type\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11658, __PRETTY_FUNCTION__)); | |||
11659 | Result += Info.Ctx.toCharUnitsFromBits(RL.getFieldOffset(i)); | |||
11660 | CurrentType = MemberDecl->getType().getNonReferenceType(); | |||
11661 | break; | |||
11662 | } | |||
11663 | ||||
11664 | case OffsetOfNode::Identifier: | |||
11665 | llvm_unreachable("dependent __builtin_offsetof")::llvm::llvm_unreachable_internal("dependent __builtin_offsetof" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11665); | |||
11666 | ||||
11667 | case OffsetOfNode::Base: { | |||
11668 | CXXBaseSpecifier *BaseSpec = ON.getBase(); | |||
11669 | if (BaseSpec->isVirtual()) | |||
11670 | return Error(OOE); | |||
11671 | ||||
11672 | // Find the layout of the class whose base we are looking into. | |||
11673 | const RecordType *RT = CurrentType->getAs<RecordType>(); | |||
11674 | if (!RT) | |||
11675 | return Error(OOE); | |||
11676 | RecordDecl *RD = RT->getDecl(); | |||
11677 | if (RD->isInvalidDecl()) return false; | |||
11678 | const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD); | |||
11679 | ||||
11680 | // Find the base class itself. | |||
11681 | CurrentType = BaseSpec->getType(); | |||
11682 | const RecordType *BaseRT = CurrentType->getAs<RecordType>(); | |||
11683 | if (!BaseRT) | |||
11684 | return Error(OOE); | |||
11685 | ||||
11686 | // Add the offset to the base. | |||
11687 | Result += RL.getBaseClassOffset(cast<CXXRecordDecl>(BaseRT->getDecl())); | |||
11688 | break; | |||
11689 | } | |||
11690 | } | |||
11691 | } | |||
11692 | return Success(Result, OOE); | |||
11693 | } | |||
11694 | ||||
11695 | bool IntExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { | |||
11696 | switch (E->getOpcode()) { | |||
11697 | default: | |||
11698 | // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. | |||
11699 | // See C99 6.6p3. | |||
11700 | return Error(E); | |||
11701 | case UO_Extension: | |||
11702 | // FIXME: Should extension allow i-c-e extension expressions in its scope? | |||
11703 | // If so, we could clear the diagnostic ID. | |||
11704 | return Visit(E->getSubExpr()); | |||
11705 | case UO_Plus: | |||
11706 | // The result is just the value. | |||
11707 | return Visit(E->getSubExpr()); | |||
11708 | case UO_Minus: { | |||
11709 | if (!Visit(E->getSubExpr())) | |||
11710 | return false; | |||
11711 | if (!Result.isInt()) return Error(E); | |||
11712 | const APSInt &Value = Result.getInt(); | |||
11713 | if (Value.isSigned() && Value.isMinSignedValue() && E->canOverflow() && | |||
11714 | !HandleOverflow(Info, E, -Value.extend(Value.getBitWidth() + 1), | |||
11715 | E->getType())) | |||
11716 | return false; | |||
11717 | return Success(-Value, E); | |||
11718 | } | |||
11719 | case UO_Not: { | |||
11720 | if (!Visit(E->getSubExpr())) | |||
11721 | return false; | |||
11722 | if (!Result.isInt()) return Error(E); | |||
11723 | return Success(~Result.getInt(), E); | |||
11724 | } | |||
11725 | case UO_LNot: { | |||
11726 | bool bres; | |||
11727 | if (!EvaluateAsBooleanCondition(E->getSubExpr(), bres, Info)) | |||
11728 | return false; | |||
11729 | return Success(!bres, E); | |||
11730 | } | |||
11731 | } | |||
11732 | } | |||
11733 | ||||
11734 | /// HandleCast - This is used to evaluate implicit or explicit casts where the | |||
11735 | /// result type is integer. | |||
11736 | bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
11737 | const Expr *SubExpr = E->getSubExpr(); | |||
11738 | QualType DestType = E->getType(); | |||
11739 | QualType SrcType = SubExpr->getType(); | |||
11740 | ||||
11741 | switch (E->getCastKind()) { | |||
11742 | case CK_BaseToDerived: | |||
11743 | case CK_DerivedToBase: | |||
11744 | case CK_UncheckedDerivedToBase: | |||
11745 | case CK_Dynamic: | |||
11746 | case CK_ToUnion: | |||
11747 | case CK_ArrayToPointerDecay: | |||
11748 | case CK_FunctionToPointerDecay: | |||
11749 | case CK_NullToPointer: | |||
11750 | case CK_NullToMemberPointer: | |||
11751 | case CK_BaseToDerivedMemberPointer: | |||
11752 | case CK_DerivedToBaseMemberPointer: | |||
11753 | case CK_ReinterpretMemberPointer: | |||
11754 | case CK_ConstructorConversion: | |||
11755 | case CK_IntegralToPointer: | |||
11756 | case CK_ToVoid: | |||
11757 | case CK_VectorSplat: | |||
11758 | case CK_IntegralToFloating: | |||
11759 | case CK_FloatingCast: | |||
11760 | case CK_CPointerToObjCPointerCast: | |||
11761 | case CK_BlockPointerToObjCPointerCast: | |||
11762 | case CK_AnyPointerToBlockPointerCast: | |||
11763 | case CK_ObjCObjectLValueCast: | |||
11764 | case CK_FloatingRealToComplex: | |||
11765 | case CK_FloatingComplexToReal: | |||
11766 | case CK_FloatingComplexCast: | |||
11767 | case CK_FloatingComplexToIntegralComplex: | |||
11768 | case CK_IntegralRealToComplex: | |||
11769 | case CK_IntegralComplexCast: | |||
11770 | case CK_IntegralComplexToFloatingComplex: | |||
11771 | case CK_BuiltinFnToFnPtr: | |||
11772 | case CK_ZeroToOCLOpaqueType: | |||
11773 | case CK_NonAtomicToAtomic: | |||
11774 | case CK_AddressSpaceConversion: | |||
11775 | case CK_IntToOCLSampler: | |||
11776 | case CK_FixedPointCast: | |||
11777 | case CK_IntegralToFixedPoint: | |||
11778 | llvm_unreachable("invalid cast kind for integral value")::llvm::llvm_unreachable_internal("invalid cast kind for integral value" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11778); | |||
11779 | ||||
11780 | case CK_BitCast: | |||
11781 | case CK_Dependent: | |||
11782 | case CK_LValueBitCast: | |||
11783 | case CK_ARCProduceObject: | |||
11784 | case CK_ARCConsumeObject: | |||
11785 | case CK_ARCReclaimReturnedObject: | |||
11786 | case CK_ARCExtendBlockObject: | |||
11787 | case CK_CopyAndAutoreleaseBlockObject: | |||
11788 | return Error(E); | |||
11789 | ||||
11790 | case CK_UserDefinedConversion: | |||
11791 | case CK_LValueToRValue: | |||
11792 | case CK_AtomicToNonAtomic: | |||
11793 | case CK_NoOp: | |||
11794 | case CK_LValueToRValueBitCast: | |||
11795 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
11796 | ||||
11797 | case CK_MemberPointerToBoolean: | |||
11798 | case CK_PointerToBoolean: | |||
11799 | case CK_IntegralToBoolean: | |||
11800 | case CK_FloatingToBoolean: | |||
11801 | case CK_BooleanToSignedIntegral: | |||
11802 | case CK_FloatingComplexToBoolean: | |||
11803 | case CK_IntegralComplexToBoolean: { | |||
11804 | bool BoolResult; | |||
11805 | if (!EvaluateAsBooleanCondition(SubExpr, BoolResult, Info)) | |||
11806 | return false; | |||
11807 | uint64_t IntResult = BoolResult; | |||
11808 | if (BoolResult && E->getCastKind() == CK_BooleanToSignedIntegral) | |||
11809 | IntResult = (uint64_t)-1; | |||
11810 | return Success(IntResult, E); | |||
11811 | } | |||
11812 | ||||
11813 | case CK_FixedPointToIntegral: { | |||
11814 | APFixedPoint Src(Info.Ctx.getFixedPointSemantics(SrcType)); | |||
11815 | if (!EvaluateFixedPoint(SubExpr, Src, Info)) | |||
11816 | return false; | |||
11817 | bool Overflowed; | |||
11818 | llvm::APSInt Result = Src.convertToInt( | |||
11819 | Info.Ctx.getIntWidth(DestType), | |||
11820 | DestType->isSignedIntegerOrEnumerationType(), &Overflowed); | |||
11821 | if (Overflowed && !HandleOverflow(Info, E, Result, DestType)) | |||
11822 | return false; | |||
11823 | return Success(Result, E); | |||
11824 | } | |||
11825 | ||||
11826 | case CK_FixedPointToBoolean: { | |||
11827 | // Unsigned padding does not affect this. | |||
11828 | APValue Val; | |||
11829 | if (!Evaluate(Val, Info, SubExpr)) | |||
11830 | return false; | |||
11831 | return Success(Val.getFixedPoint().getBoolValue(), E); | |||
11832 | } | |||
11833 | ||||
11834 | case CK_IntegralCast: { | |||
11835 | if (!Visit(SubExpr)) | |||
11836 | return false; | |||
11837 | ||||
11838 | if (!Result.isInt()) { | |||
11839 | // Allow casts of address-of-label differences if they are no-ops | |||
11840 | // or narrowing. (The narrowing case isn't actually guaranteed to | |||
11841 | // be constant-evaluatable except in some narrow cases which are hard | |||
11842 | // to detect here. We let it through on the assumption the user knows | |||
11843 | // what they are doing.) | |||
11844 | if (Result.isAddrLabelDiff()) | |||
11845 | return Info.Ctx.getTypeSize(DestType) <= Info.Ctx.getTypeSize(SrcType); | |||
11846 | // Only allow casts of lvalues if they are lossless. | |||
11847 | return Info.Ctx.getTypeSize(DestType) == Info.Ctx.getTypeSize(SrcType); | |||
11848 | } | |||
11849 | ||||
11850 | return Success(HandleIntToIntCast(Info, E, DestType, SrcType, | |||
11851 | Result.getInt()), E); | |||
11852 | } | |||
11853 | ||||
11854 | case CK_PointerToIntegral: { | |||
11855 | CCEDiag(E, diag::note_constexpr_invalid_cast) << 2; | |||
11856 | ||||
11857 | LValue LV; | |||
11858 | if (!EvaluatePointer(SubExpr, LV, Info)) | |||
11859 | return false; | |||
11860 | ||||
11861 | if (LV.getLValueBase()) { | |||
11862 | // Only allow based lvalue casts if they are lossless. | |||
11863 | // FIXME: Allow a larger integer size than the pointer size, and allow | |||
11864 | // narrowing back down to pointer width in subsequent integral casts. | |||
11865 | // FIXME: Check integer type's active bits, not its type size. | |||
11866 | if (Info.Ctx.getTypeSize(DestType) != Info.Ctx.getTypeSize(SrcType)) | |||
11867 | return Error(E); | |||
11868 | ||||
11869 | LV.Designator.setInvalid(); | |||
11870 | LV.moveInto(Result); | |||
11871 | return true; | |||
11872 | } | |||
11873 | ||||
11874 | APSInt AsInt; | |||
11875 | APValue V; | |||
11876 | LV.moveInto(V); | |||
11877 | if (!V.toIntegralConstant(AsInt, SrcType, Info.Ctx)) | |||
11878 | llvm_unreachable("Can't cast this!")::llvm::llvm_unreachable_internal("Can't cast this!", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11878); | |||
11879 | ||||
11880 | return Success(HandleIntToIntCast(Info, E, DestType, SrcType, AsInt), E); | |||
11881 | } | |||
11882 | ||||
11883 | case CK_IntegralComplexToReal: { | |||
11884 | ComplexValue C; | |||
11885 | if (!EvaluateComplex(SubExpr, C, Info)) | |||
11886 | return false; | |||
11887 | return Success(C.getComplexIntReal(), E); | |||
11888 | } | |||
11889 | ||||
11890 | case CK_FloatingToIntegral: { | |||
11891 | APFloat F(0.0); | |||
11892 | if (!EvaluateFloat(SubExpr, F, Info)) | |||
11893 | return false; | |||
11894 | ||||
11895 | APSInt Value; | |||
11896 | if (!HandleFloatToIntCast(Info, E, SrcType, F, DestType, Value)) | |||
11897 | return false; | |||
11898 | return Success(Value, E); | |||
11899 | } | |||
11900 | } | |||
11901 | ||||
11902 | llvm_unreachable("unknown cast resulting in integral value")::llvm::llvm_unreachable_internal("unknown cast resulting in integral value" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11902); | |||
11903 | } | |||
11904 | ||||
11905 | bool IntExprEvaluator::VisitUnaryReal(const UnaryOperator *E) { | |||
11906 | if (E->getSubExpr()->getType()->isAnyComplexType()) { | |||
11907 | ComplexValue LV; | |||
11908 | if (!EvaluateComplex(E->getSubExpr(), LV, Info)) | |||
11909 | return false; | |||
11910 | if (!LV.isComplexInt()) | |||
11911 | return Error(E); | |||
11912 | return Success(LV.getComplexIntReal(), E); | |||
11913 | } | |||
11914 | ||||
11915 | return Visit(E->getSubExpr()); | |||
11916 | } | |||
11917 | ||||
11918 | bool IntExprEvaluator::VisitUnaryImag(const UnaryOperator *E) { | |||
11919 | if (E->getSubExpr()->getType()->isComplexIntegerType()) { | |||
11920 | ComplexValue LV; | |||
11921 | if (!EvaluateComplex(E->getSubExpr(), LV, Info)) | |||
11922 | return false; | |||
11923 | if (!LV.isComplexInt()) | |||
11924 | return Error(E); | |||
11925 | return Success(LV.getComplexIntImag(), E); | |||
11926 | } | |||
11927 | ||||
11928 | VisitIgnoredValue(E->getSubExpr()); | |||
11929 | return Success(0, E); | |||
11930 | } | |||
11931 | ||||
11932 | bool IntExprEvaluator::VisitSizeOfPackExpr(const SizeOfPackExpr *E) { | |||
11933 | return Success(E->getPackLength(), E); | |||
11934 | } | |||
11935 | ||||
11936 | bool IntExprEvaluator::VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) { | |||
11937 | return Success(E->getValue(), E); | |||
11938 | } | |||
11939 | ||||
11940 | bool FixedPointExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { | |||
11941 | switch (E->getOpcode()) { | |||
11942 | default: | |||
11943 | // Invalid unary operators | |||
11944 | return Error(E); | |||
11945 | case UO_Plus: | |||
11946 | // The result is just the value. | |||
11947 | return Visit(E->getSubExpr()); | |||
11948 | case UO_Minus: { | |||
11949 | if (!Visit(E->getSubExpr())) return false; | |||
11950 | if (!Result.isFixedPoint()) | |||
11951 | return Error(E); | |||
11952 | bool Overflowed; | |||
11953 | APFixedPoint Negated = Result.getFixedPoint().negate(&Overflowed); | |||
11954 | if (Overflowed && !HandleOverflow(Info, E, Negated, E->getType())) | |||
11955 | return false; | |||
11956 | return Success(Negated, E); | |||
11957 | } | |||
11958 | case UO_LNot: { | |||
11959 | bool bres; | |||
11960 | if (!EvaluateAsBooleanCondition(E->getSubExpr(), bres, Info)) | |||
11961 | return false; | |||
11962 | return Success(!bres, E); | |||
11963 | } | |||
11964 | } | |||
11965 | } | |||
11966 | ||||
11967 | bool FixedPointExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
11968 | const Expr *SubExpr = E->getSubExpr(); | |||
11969 | QualType DestType = E->getType(); | |||
11970 | assert(DestType->isFixedPointType() &&((DestType->isFixedPointType() && "Expected destination type to be a fixed point type" ) ? static_cast<void> (0) : __assert_fail ("DestType->isFixedPointType() && \"Expected destination type to be a fixed point type\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11971, __PRETTY_FUNCTION__)) | |||
11971 | "Expected destination type to be a fixed point type")((DestType->isFixedPointType() && "Expected destination type to be a fixed point type" ) ? static_cast<void> (0) : __assert_fail ("DestType->isFixedPointType() && \"Expected destination type to be a fixed point type\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 11971, __PRETTY_FUNCTION__)); | |||
11972 | auto DestFXSema = Info.Ctx.getFixedPointSemantics(DestType); | |||
11973 | ||||
11974 | switch (E->getCastKind()) { | |||
11975 | case CK_FixedPointCast: { | |||
11976 | APFixedPoint Src(Info.Ctx.getFixedPointSemantics(SubExpr->getType())); | |||
11977 | if (!EvaluateFixedPoint(SubExpr, Src, Info)) | |||
11978 | return false; | |||
11979 | bool Overflowed; | |||
11980 | APFixedPoint Result = Src.convert(DestFXSema, &Overflowed); | |||
11981 | if (Overflowed && !HandleOverflow(Info, E, Result, DestType)) | |||
11982 | return false; | |||
11983 | return Success(Result, E); | |||
11984 | } | |||
11985 | case CK_IntegralToFixedPoint: { | |||
11986 | APSInt Src; | |||
11987 | if (!EvaluateInteger(SubExpr, Src, Info)) | |||
11988 | return false; | |||
11989 | ||||
11990 | bool Overflowed; | |||
11991 | APFixedPoint IntResult = APFixedPoint::getFromIntValue( | |||
11992 | Src, Info.Ctx.getFixedPointSemantics(DestType), &Overflowed); | |||
11993 | ||||
11994 | if (Overflowed && !HandleOverflow(Info, E, IntResult, DestType)) | |||
11995 | return false; | |||
11996 | ||||
11997 | return Success(IntResult, E); | |||
11998 | } | |||
11999 | case CK_NoOp: | |||
12000 | case CK_LValueToRValue: | |||
12001 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
12002 | default: | |||
12003 | return Error(E); | |||
12004 | } | |||
12005 | } | |||
12006 | ||||
12007 | bool FixedPointExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
12008 | const Expr *LHS = E->getLHS(); | |||
12009 | const Expr *RHS = E->getRHS(); | |||
12010 | FixedPointSemantics ResultFXSema = | |||
12011 | Info.Ctx.getFixedPointSemantics(E->getType()); | |||
12012 | ||||
12013 | APFixedPoint LHSFX(Info.Ctx.getFixedPointSemantics(LHS->getType())); | |||
12014 | if (!EvaluateFixedPointOrInteger(LHS, LHSFX, Info)) | |||
12015 | return false; | |||
12016 | APFixedPoint RHSFX(Info.Ctx.getFixedPointSemantics(RHS->getType())); | |||
12017 | if (!EvaluateFixedPointOrInteger(RHS, RHSFX, Info)) | |||
12018 | return false; | |||
12019 | ||||
12020 | switch (E->getOpcode()) { | |||
12021 | case BO_Add: { | |||
12022 | bool AddOverflow, ConversionOverflow; | |||
12023 | APFixedPoint Result = LHSFX.add(RHSFX, &AddOverflow) | |||
12024 | .convert(ResultFXSema, &ConversionOverflow); | |||
12025 | if ((AddOverflow || ConversionOverflow) && | |||
12026 | !HandleOverflow(Info, E, Result, E->getType())) | |||
12027 | return false; | |||
12028 | return Success(Result, E); | |||
12029 | } | |||
12030 | default: | |||
12031 | return false; | |||
12032 | } | |||
12033 | llvm_unreachable("Should've exited before this")::llvm::llvm_unreachable_internal("Should've exited before this" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12033); | |||
12034 | } | |||
12035 | ||||
12036 | //===----------------------------------------------------------------------===// | |||
12037 | // Float Evaluation | |||
12038 | //===----------------------------------------------------------------------===// | |||
12039 | ||||
12040 | namespace { | |||
12041 | class FloatExprEvaluator | |||
12042 | : public ExprEvaluatorBase<FloatExprEvaluator> { | |||
12043 | APFloat &Result; | |||
12044 | public: | |||
12045 | FloatExprEvaluator(EvalInfo &info, APFloat &result) | |||
12046 | : ExprEvaluatorBaseTy(info), Result(result) {} | |||
12047 | ||||
12048 | bool Success(const APValue &V, const Expr *e) { | |||
12049 | Result = V.getFloat(); | |||
12050 | return true; | |||
12051 | } | |||
12052 | ||||
12053 | bool ZeroInitialization(const Expr *E) { | |||
12054 | Result = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(E->getType())); | |||
12055 | return true; | |||
12056 | } | |||
12057 | ||||
12058 | bool VisitCallExpr(const CallExpr *E); | |||
12059 | ||||
12060 | bool VisitUnaryOperator(const UnaryOperator *E); | |||
12061 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
12062 | bool VisitFloatingLiteral(const FloatingLiteral *E); | |||
12063 | bool VisitCastExpr(const CastExpr *E); | |||
12064 | ||||
12065 | bool VisitUnaryReal(const UnaryOperator *E); | |||
12066 | bool VisitUnaryImag(const UnaryOperator *E); | |||
12067 | ||||
12068 | // FIXME: Missing: array subscript of vector, member of vector | |||
12069 | }; | |||
12070 | } // end anonymous namespace | |||
12071 | ||||
12072 | static bool EvaluateFloat(const Expr* E, APFloat& Result, EvalInfo &Info) { | |||
12073 | assert(E->isRValue() && E->getType()->isRealFloatingType())((E->isRValue() && E->getType()->isRealFloatingType ()) ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isRealFloatingType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12073, __PRETTY_FUNCTION__)); | |||
12074 | return FloatExprEvaluator(Info, Result).Visit(E); | |||
12075 | } | |||
12076 | ||||
12077 | static bool TryEvaluateBuiltinNaN(const ASTContext &Context, | |||
12078 | QualType ResultTy, | |||
12079 | const Expr *Arg, | |||
12080 | bool SNaN, | |||
12081 | llvm::APFloat &Result) { | |||
12082 | const StringLiteral *S = dyn_cast<StringLiteral>(Arg->IgnoreParenCasts()); | |||
12083 | if (!S) return false; | |||
12084 | ||||
12085 | const llvm::fltSemantics &Sem = Context.getFloatTypeSemantics(ResultTy); | |||
12086 | ||||
12087 | llvm::APInt fill; | |||
12088 | ||||
12089 | // Treat empty strings as if they were zero. | |||
12090 | if (S->getString().empty()) | |||
12091 | fill = llvm::APInt(32, 0); | |||
12092 | else if (S->getString().getAsInteger(0, fill)) | |||
12093 | return false; | |||
12094 | ||||
12095 | if (Context.getTargetInfo().isNan2008()) { | |||
12096 | if (SNaN) | |||
12097 | Result = llvm::APFloat::getSNaN(Sem, false, &fill); | |||
12098 | else | |||
12099 | Result = llvm::APFloat::getQNaN(Sem, false, &fill); | |||
12100 | } else { | |||
12101 | // Prior to IEEE 754-2008, architectures were allowed to choose whether | |||
12102 | // the first bit of their significand was set for qNaN or sNaN. MIPS chose | |||
12103 | // a different encoding to what became a standard in 2008, and for pre- | |||
12104 | // 2008 revisions, MIPS interpreted sNaN-2008 as qNan and qNaN-2008 as | |||
12105 | // sNaN. This is now known as "legacy NaN" encoding. | |||
12106 | if (SNaN) | |||
12107 | Result = llvm::APFloat::getQNaN(Sem, false, &fill); | |||
12108 | else | |||
12109 | Result = llvm::APFloat::getSNaN(Sem, false, &fill); | |||
12110 | } | |||
12111 | ||||
12112 | return true; | |||
12113 | } | |||
12114 | ||||
12115 | bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) { | |||
12116 | switch (E->getBuiltinCallee()) { | |||
12117 | default: | |||
12118 | return ExprEvaluatorBaseTy::VisitCallExpr(E); | |||
12119 | ||||
12120 | case Builtin::BI__builtin_huge_val: | |||
12121 | case Builtin::BI__builtin_huge_valf: | |||
12122 | case Builtin::BI__builtin_huge_vall: | |||
12123 | case Builtin::BI__builtin_huge_valf128: | |||
12124 | case Builtin::BI__builtin_inf: | |||
12125 | case Builtin::BI__builtin_inff: | |||
12126 | case Builtin::BI__builtin_infl: | |||
12127 | case Builtin::BI__builtin_inff128: { | |||
12128 | const llvm::fltSemantics &Sem = | |||
12129 | Info.Ctx.getFloatTypeSemantics(E->getType()); | |||
12130 | Result = llvm::APFloat::getInf(Sem); | |||
12131 | return true; | |||
12132 | } | |||
12133 | ||||
12134 | case Builtin::BI__builtin_nans: | |||
12135 | case Builtin::BI__builtin_nansf: | |||
12136 | case Builtin::BI__builtin_nansl: | |||
12137 | case Builtin::BI__builtin_nansf128: | |||
12138 | if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0), | |||
12139 | true, Result)) | |||
12140 | return Error(E); | |||
12141 | return true; | |||
12142 | ||||
12143 | case Builtin::BI__builtin_nan: | |||
12144 | case Builtin::BI__builtin_nanf: | |||
12145 | case Builtin::BI__builtin_nanl: | |||
12146 | case Builtin::BI__builtin_nanf128: | |||
12147 | // If this is __builtin_nan() turn this into a nan, otherwise we | |||
12148 | // can't constant fold it. | |||
12149 | if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0), | |||
12150 | false, Result)) | |||
12151 | return Error(E); | |||
12152 | return true; | |||
12153 | ||||
12154 | case Builtin::BI__builtin_fabs: | |||
12155 | case Builtin::BI__builtin_fabsf: | |||
12156 | case Builtin::BI__builtin_fabsl: | |||
12157 | case Builtin::BI__builtin_fabsf128: | |||
12158 | if (!EvaluateFloat(E->getArg(0), Result, Info)) | |||
12159 | return false; | |||
12160 | ||||
12161 | if (Result.isNegative()) | |||
12162 | Result.changeSign(); | |||
12163 | return true; | |||
12164 | ||||
12165 | // FIXME: Builtin::BI__builtin_powi | |||
12166 | // FIXME: Builtin::BI__builtin_powif | |||
12167 | // FIXME: Builtin::BI__builtin_powil | |||
12168 | ||||
12169 | case Builtin::BI__builtin_copysign: | |||
12170 | case Builtin::BI__builtin_copysignf: | |||
12171 | case Builtin::BI__builtin_copysignl: | |||
12172 | case Builtin::BI__builtin_copysignf128: { | |||
12173 | APFloat RHS(0.); | |||
12174 | if (!EvaluateFloat(E->getArg(0), Result, Info) || | |||
12175 | !EvaluateFloat(E->getArg(1), RHS, Info)) | |||
12176 | return false; | |||
12177 | Result.copySign(RHS); | |||
12178 | return true; | |||
12179 | } | |||
12180 | } | |||
12181 | } | |||
12182 | ||||
12183 | bool FloatExprEvaluator::VisitUnaryReal(const UnaryOperator *E) { | |||
12184 | if (E->getSubExpr()->getType()->isAnyComplexType()) { | |||
12185 | ComplexValue CV; | |||
12186 | if (!EvaluateComplex(E->getSubExpr(), CV, Info)) | |||
12187 | return false; | |||
12188 | Result = CV.FloatReal; | |||
12189 | return true; | |||
12190 | } | |||
12191 | ||||
12192 | return Visit(E->getSubExpr()); | |||
12193 | } | |||
12194 | ||||
12195 | bool FloatExprEvaluator::VisitUnaryImag(const UnaryOperator *E) { | |||
12196 | if (E->getSubExpr()->getType()->isAnyComplexType()) { | |||
12197 | ComplexValue CV; | |||
12198 | if (!EvaluateComplex(E->getSubExpr(), CV, Info)) | |||
12199 | return false; | |||
12200 | Result = CV.FloatImag; | |||
12201 | return true; | |||
12202 | } | |||
12203 | ||||
12204 | VisitIgnoredValue(E->getSubExpr()); | |||
12205 | const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(E->getType()); | |||
12206 | Result = llvm::APFloat::getZero(Sem); | |||
12207 | return true; | |||
12208 | } | |||
12209 | ||||
12210 | bool FloatExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { | |||
12211 | switch (E->getOpcode()) { | |||
12212 | default: return Error(E); | |||
12213 | case UO_Plus: | |||
12214 | return EvaluateFloat(E->getSubExpr(), Result, Info); | |||
12215 | case UO_Minus: | |||
12216 | if (!EvaluateFloat(E->getSubExpr(), Result, Info)) | |||
12217 | return false; | |||
12218 | Result.changeSign(); | |||
12219 | return true; | |||
12220 | } | |||
12221 | } | |||
12222 | ||||
12223 | bool FloatExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
12224 | if (E->isPtrMemOp() || E->isAssignmentOp() || E->getOpcode() == BO_Comma) | |||
12225 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
12226 | ||||
12227 | APFloat RHS(0.0); | |||
12228 | bool LHSOK = EvaluateFloat(E->getLHS(), Result, Info); | |||
12229 | if (!LHSOK && !Info.noteFailure()) | |||
12230 | return false; | |||
12231 | return EvaluateFloat(E->getRHS(), RHS, Info) && LHSOK && | |||
12232 | handleFloatFloatBinOp(Info, E, Result, E->getOpcode(), RHS); | |||
12233 | } | |||
12234 | ||||
12235 | bool FloatExprEvaluator::VisitFloatingLiteral(const FloatingLiteral *E) { | |||
12236 | Result = E->getValue(); | |||
12237 | return true; | |||
12238 | } | |||
12239 | ||||
12240 | bool FloatExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
12241 | const Expr* SubExpr = E->getSubExpr(); | |||
12242 | ||||
12243 | switch (E->getCastKind()) { | |||
12244 | default: | |||
12245 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
12246 | ||||
12247 | case CK_IntegralToFloating: { | |||
12248 | APSInt IntResult; | |||
12249 | return EvaluateInteger(SubExpr, IntResult, Info) && | |||
12250 | HandleIntToFloatCast(Info, E, SubExpr->getType(), IntResult, | |||
12251 | E->getType(), Result); | |||
12252 | } | |||
12253 | ||||
12254 | case CK_FloatingCast: { | |||
12255 | if (!Visit(SubExpr)) | |||
12256 | return false; | |||
12257 | return HandleFloatToFloatCast(Info, E, SubExpr->getType(), E->getType(), | |||
12258 | Result); | |||
12259 | } | |||
12260 | ||||
12261 | case CK_FloatingComplexToReal: { | |||
12262 | ComplexValue V; | |||
12263 | if (!EvaluateComplex(SubExpr, V, Info)) | |||
12264 | return false; | |||
12265 | Result = V.getComplexFloatReal(); | |||
12266 | return true; | |||
12267 | } | |||
12268 | } | |||
12269 | } | |||
12270 | ||||
12271 | //===----------------------------------------------------------------------===// | |||
12272 | // Complex Evaluation (for float and integer) | |||
12273 | //===----------------------------------------------------------------------===// | |||
12274 | ||||
12275 | namespace { | |||
12276 | class ComplexExprEvaluator | |||
12277 | : public ExprEvaluatorBase<ComplexExprEvaluator> { | |||
12278 | ComplexValue &Result; | |||
12279 | ||||
12280 | public: | |||
12281 | ComplexExprEvaluator(EvalInfo &info, ComplexValue &Result) | |||
12282 | : ExprEvaluatorBaseTy(info), Result(Result) {} | |||
12283 | ||||
12284 | bool Success(const APValue &V, const Expr *e) { | |||
12285 | Result.setFrom(V); | |||
12286 | return true; | |||
12287 | } | |||
12288 | ||||
12289 | bool ZeroInitialization(const Expr *E); | |||
12290 | ||||
12291 | //===--------------------------------------------------------------------===// | |||
12292 | // Visitor Methods | |||
12293 | //===--------------------------------------------------------------------===// | |||
12294 | ||||
12295 | bool VisitImaginaryLiteral(const ImaginaryLiteral *E); | |||
12296 | bool VisitCastExpr(const CastExpr *E); | |||
12297 | bool VisitBinaryOperator(const BinaryOperator *E); | |||
12298 | bool VisitUnaryOperator(const UnaryOperator *E); | |||
12299 | bool VisitInitListExpr(const InitListExpr *E); | |||
12300 | }; | |||
12301 | } // end anonymous namespace | |||
12302 | ||||
12303 | static bool EvaluateComplex(const Expr *E, ComplexValue &Result, | |||
12304 | EvalInfo &Info) { | |||
12305 | assert(E->isRValue() && E->getType()->isAnyComplexType())((E->isRValue() && E->getType()->isAnyComplexType ()) ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isAnyComplexType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12305, __PRETTY_FUNCTION__)); | |||
12306 | return ComplexExprEvaluator(Info, Result).Visit(E); | |||
12307 | } | |||
12308 | ||||
12309 | bool ComplexExprEvaluator::ZeroInitialization(const Expr *E) { | |||
12310 | QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType(); | |||
12311 | if (ElemTy->isRealFloatingType()) { | |||
12312 | Result.makeComplexFloat(); | |||
12313 | APFloat Zero = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(ElemTy)); | |||
12314 | Result.FloatReal = Zero; | |||
12315 | Result.FloatImag = Zero; | |||
12316 | } else { | |||
12317 | Result.makeComplexInt(); | |||
12318 | APSInt Zero = Info.Ctx.MakeIntValue(0, ElemTy); | |||
12319 | Result.IntReal = Zero; | |||
12320 | Result.IntImag = Zero; | |||
12321 | } | |||
12322 | return true; | |||
12323 | } | |||
12324 | ||||
12325 | bool ComplexExprEvaluator::VisitImaginaryLiteral(const ImaginaryLiteral *E) { | |||
12326 | const Expr* SubExpr = E->getSubExpr(); | |||
12327 | ||||
12328 | if (SubExpr->getType()->isRealFloatingType()) { | |||
12329 | Result.makeComplexFloat(); | |||
12330 | APFloat &Imag = Result.FloatImag; | |||
12331 | if (!EvaluateFloat(SubExpr, Imag, Info)) | |||
12332 | return false; | |||
12333 | ||||
12334 | Result.FloatReal = APFloat(Imag.getSemantics()); | |||
12335 | return true; | |||
12336 | } else { | |||
12337 | assert(SubExpr->getType()->isIntegerType() &&((SubExpr->getType()->isIntegerType() && "Unexpected imaginary literal." ) ? static_cast<void> (0) : __assert_fail ("SubExpr->getType()->isIntegerType() && \"Unexpected imaginary literal.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12338, __PRETTY_FUNCTION__)) | |||
12338 | "Unexpected imaginary literal.")((SubExpr->getType()->isIntegerType() && "Unexpected imaginary literal." ) ? static_cast<void> (0) : __assert_fail ("SubExpr->getType()->isIntegerType() && \"Unexpected imaginary literal.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12338, __PRETTY_FUNCTION__)); | |||
12339 | ||||
12340 | Result.makeComplexInt(); | |||
12341 | APSInt &Imag = Result.IntImag; | |||
12342 | if (!EvaluateInteger(SubExpr, Imag, Info)) | |||
12343 | return false; | |||
12344 | ||||
12345 | Result.IntReal = APSInt(Imag.getBitWidth(), !Imag.isSigned()); | |||
12346 | return true; | |||
12347 | } | |||
12348 | } | |||
12349 | ||||
12350 | bool ComplexExprEvaluator::VisitCastExpr(const CastExpr *E) { | |||
12351 | ||||
12352 | switch (E->getCastKind()) { | |||
12353 | case CK_BitCast: | |||
12354 | case CK_BaseToDerived: | |||
12355 | case CK_DerivedToBase: | |||
12356 | case CK_UncheckedDerivedToBase: | |||
12357 | case CK_Dynamic: | |||
12358 | case CK_ToUnion: | |||
12359 | case CK_ArrayToPointerDecay: | |||
12360 | case CK_FunctionToPointerDecay: | |||
12361 | case CK_NullToPointer: | |||
12362 | case CK_NullToMemberPointer: | |||
12363 | case CK_BaseToDerivedMemberPointer: | |||
12364 | case CK_DerivedToBaseMemberPointer: | |||
12365 | case CK_MemberPointerToBoolean: | |||
12366 | case CK_ReinterpretMemberPointer: | |||
12367 | case CK_ConstructorConversion: | |||
12368 | case CK_IntegralToPointer: | |||
12369 | case CK_PointerToIntegral: | |||
12370 | case CK_PointerToBoolean: | |||
12371 | case CK_ToVoid: | |||
12372 | case CK_VectorSplat: | |||
12373 | case CK_IntegralCast: | |||
12374 | case CK_BooleanToSignedIntegral: | |||
12375 | case CK_IntegralToBoolean: | |||
12376 | case CK_IntegralToFloating: | |||
12377 | case CK_FloatingToIntegral: | |||
12378 | case CK_FloatingToBoolean: | |||
12379 | case CK_FloatingCast: | |||
12380 | case CK_CPointerToObjCPointerCast: | |||
12381 | case CK_BlockPointerToObjCPointerCast: | |||
12382 | case CK_AnyPointerToBlockPointerCast: | |||
12383 | case CK_ObjCObjectLValueCast: | |||
12384 | case CK_FloatingComplexToReal: | |||
12385 | case CK_FloatingComplexToBoolean: | |||
12386 | case CK_IntegralComplexToReal: | |||
12387 | case CK_IntegralComplexToBoolean: | |||
12388 | case CK_ARCProduceObject: | |||
12389 | case CK_ARCConsumeObject: | |||
12390 | case CK_ARCReclaimReturnedObject: | |||
12391 | case CK_ARCExtendBlockObject: | |||
12392 | case CK_CopyAndAutoreleaseBlockObject: | |||
12393 | case CK_BuiltinFnToFnPtr: | |||
12394 | case CK_ZeroToOCLOpaqueType: | |||
12395 | case CK_NonAtomicToAtomic: | |||
12396 | case CK_AddressSpaceConversion: | |||
12397 | case CK_IntToOCLSampler: | |||
12398 | case CK_FixedPointCast: | |||
12399 | case CK_FixedPointToBoolean: | |||
12400 | case CK_FixedPointToIntegral: | |||
12401 | case CK_IntegralToFixedPoint: | |||
12402 | llvm_unreachable("invalid cast kind for complex value")::llvm::llvm_unreachable_internal("invalid cast kind for complex value" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12402); | |||
12403 | ||||
12404 | case CK_LValueToRValue: | |||
12405 | case CK_AtomicToNonAtomic: | |||
12406 | case CK_NoOp: | |||
12407 | case CK_LValueToRValueBitCast: | |||
12408 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
12409 | ||||
12410 | case CK_Dependent: | |||
12411 | case CK_LValueBitCast: | |||
12412 | case CK_UserDefinedConversion: | |||
12413 | return Error(E); | |||
12414 | ||||
12415 | case CK_FloatingRealToComplex: { | |||
12416 | APFloat &Real = Result.FloatReal; | |||
12417 | if (!EvaluateFloat(E->getSubExpr(), Real, Info)) | |||
12418 | return false; | |||
12419 | ||||
12420 | Result.makeComplexFloat(); | |||
12421 | Result.FloatImag = APFloat(Real.getSemantics()); | |||
12422 | return true; | |||
12423 | } | |||
12424 | ||||
12425 | case CK_FloatingComplexCast: { | |||
12426 | if (!Visit(E->getSubExpr())) | |||
12427 | return false; | |||
12428 | ||||
12429 | QualType To = E->getType()->getAs<ComplexType>()->getElementType(); | |||
12430 | QualType From | |||
12431 | = E->getSubExpr()->getType()->getAs<ComplexType>()->getElementType(); | |||
12432 | ||||
12433 | return HandleFloatToFloatCast(Info, E, From, To, Result.FloatReal) && | |||
12434 | HandleFloatToFloatCast(Info, E, From, To, Result.FloatImag); | |||
12435 | } | |||
12436 | ||||
12437 | case CK_FloatingComplexToIntegralComplex: { | |||
12438 | if (!Visit(E->getSubExpr())) | |||
12439 | return false; | |||
12440 | ||||
12441 | QualType To = E->getType()->getAs<ComplexType>()->getElementType(); | |||
12442 | QualType From | |||
12443 | = E->getSubExpr()->getType()->getAs<ComplexType>()->getElementType(); | |||
| ||||
12444 | Result.makeComplexInt(); | |||
12445 | return HandleFloatToIntCast(Info, E, From, Result.FloatReal, | |||
12446 | To, Result.IntReal) && | |||
12447 | HandleFloatToIntCast(Info, E, From, Result.FloatImag, | |||
12448 | To, Result.IntImag); | |||
12449 | } | |||
12450 | ||||
12451 | case CK_IntegralRealToComplex: { | |||
12452 | APSInt &Real = Result.IntReal; | |||
12453 | if (!EvaluateInteger(E->getSubExpr(), Real, Info)) | |||
12454 | return false; | |||
12455 | ||||
12456 | Result.makeComplexInt(); | |||
12457 | Result.IntImag = APSInt(Real.getBitWidth(), !Real.isSigned()); | |||
12458 | return true; | |||
12459 | } | |||
12460 | ||||
12461 | case CK_IntegralComplexCast: { | |||
12462 | if (!Visit(E->getSubExpr())) | |||
12463 | return false; | |||
12464 | ||||
12465 | QualType To = E->getType()->getAs<ComplexType>()->getElementType(); | |||
12466 | QualType From | |||
12467 | = E->getSubExpr()->getType()->getAs<ComplexType>()->getElementType(); | |||
12468 | ||||
12469 | Result.IntReal = HandleIntToIntCast(Info, E, To, From, Result.IntReal); | |||
12470 | Result.IntImag = HandleIntToIntCast(Info, E, To, From, Result.IntImag); | |||
12471 | return true; | |||
12472 | } | |||
12473 | ||||
12474 | case CK_IntegralComplexToFloatingComplex: { | |||
12475 | if (!Visit(E->getSubExpr())) | |||
12476 | return false; | |||
12477 | ||||
12478 | QualType To = E->getType()->castAs<ComplexType>()->getElementType(); | |||
12479 | QualType From | |||
12480 | = E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType(); | |||
12481 | Result.makeComplexFloat(); | |||
12482 | return HandleIntToFloatCast(Info, E, From, Result.IntReal, | |||
12483 | To, Result.FloatReal) && | |||
12484 | HandleIntToFloatCast(Info, E, From, Result.IntImag, | |||
12485 | To, Result.FloatImag); | |||
12486 | } | |||
12487 | } | |||
12488 | ||||
12489 | llvm_unreachable("unknown cast resulting in complex value")::llvm::llvm_unreachable_internal("unknown cast resulting in complex value" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12489); | |||
12490 | } | |||
12491 | ||||
12492 | bool ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { | |||
12493 | if (E->isPtrMemOp() || E->isAssignmentOp() || E->getOpcode() == BO_Comma) | |||
12494 | return ExprEvaluatorBaseTy::VisitBinaryOperator(E); | |||
12495 | ||||
12496 | // Track whether the LHS or RHS is real at the type system level. When this is | |||
12497 | // the case we can simplify our evaluation strategy. | |||
12498 | bool LHSReal = false, RHSReal = false; | |||
12499 | ||||
12500 | bool LHSOK; | |||
12501 | if (E->getLHS()->getType()->isRealFloatingType()) { | |||
12502 | LHSReal = true; | |||
12503 | APFloat &Real = Result.FloatReal; | |||
12504 | LHSOK = EvaluateFloat(E->getLHS(), Real, Info); | |||
12505 | if (LHSOK) { | |||
12506 | Result.makeComplexFloat(); | |||
12507 | Result.FloatImag = APFloat(Real.getSemantics()); | |||
12508 | } | |||
12509 | } else { | |||
12510 | LHSOK = Visit(E->getLHS()); | |||
12511 | } | |||
12512 | if (!LHSOK && !Info.noteFailure()) | |||
12513 | return false; | |||
12514 | ||||
12515 | ComplexValue RHS; | |||
12516 | if (E->getRHS()->getType()->isRealFloatingType()) { | |||
12517 | RHSReal = true; | |||
12518 | APFloat &Real = RHS.FloatReal; | |||
12519 | if (!EvaluateFloat(E->getRHS(), Real, Info) || !LHSOK) | |||
12520 | return false; | |||
12521 | RHS.makeComplexFloat(); | |||
12522 | RHS.FloatImag = APFloat(Real.getSemantics()); | |||
12523 | } else if (!EvaluateComplex(E->getRHS(), RHS, Info) || !LHSOK) | |||
12524 | return false; | |||
12525 | ||||
12526 | assert(!(LHSReal && RHSReal) &&((!(LHSReal && RHSReal) && "Cannot have both operands of a complex operation be real." ) ? static_cast<void> (0) : __assert_fail ("!(LHSReal && RHSReal) && \"Cannot have both operands of a complex operation be real.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12527, __PRETTY_FUNCTION__)) | |||
12527 | "Cannot have both operands of a complex operation be real.")((!(LHSReal && RHSReal) && "Cannot have both operands of a complex operation be real." ) ? static_cast<void> (0) : __assert_fail ("!(LHSReal && RHSReal) && \"Cannot have both operands of a complex operation be real.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12527, __PRETTY_FUNCTION__)); | |||
12528 | switch (E->getOpcode()) { | |||
12529 | default: return Error(E); | |||
12530 | case BO_Add: | |||
12531 | if (Result.isComplexFloat()) { | |||
12532 | Result.getComplexFloatReal().add(RHS.getComplexFloatReal(), | |||
12533 | APFloat::rmNearestTiesToEven); | |||
12534 | if (LHSReal) | |||
12535 | Result.getComplexFloatImag() = RHS.getComplexFloatImag(); | |||
12536 | else if (!RHSReal) | |||
12537 | Result.getComplexFloatImag().add(RHS.getComplexFloatImag(), | |||
12538 | APFloat::rmNearestTiesToEven); | |||
12539 | } else { | |||
12540 | Result.getComplexIntReal() += RHS.getComplexIntReal(); | |||
12541 | Result.getComplexIntImag() += RHS.getComplexIntImag(); | |||
12542 | } | |||
12543 | break; | |||
12544 | case BO_Sub: | |||
12545 | if (Result.isComplexFloat()) { | |||
12546 | Result.getComplexFloatReal().subtract(RHS.getComplexFloatReal(), | |||
12547 | APFloat::rmNearestTiesToEven); | |||
12548 | if (LHSReal) { | |||
12549 | Result.getComplexFloatImag() = RHS.getComplexFloatImag(); | |||
12550 | Result.getComplexFloatImag().changeSign(); | |||
12551 | } else if (!RHSReal) { | |||
12552 | Result.getComplexFloatImag().subtract(RHS.getComplexFloatImag(), | |||
12553 | APFloat::rmNearestTiesToEven); | |||
12554 | } | |||
12555 | } else { | |||
12556 | Result.getComplexIntReal() -= RHS.getComplexIntReal(); | |||
12557 | Result.getComplexIntImag() -= RHS.getComplexIntImag(); | |||
12558 | } | |||
12559 | break; | |||
12560 | case BO_Mul: | |||
12561 | if (Result.isComplexFloat()) { | |||
12562 | // This is an implementation of complex multiplication according to the | |||
12563 | // constraints laid out in C11 Annex G. The implementation uses the | |||
12564 | // following naming scheme: | |||
12565 | // (a + ib) * (c + id) | |||
12566 | ComplexValue LHS = Result; | |||
12567 | APFloat &A = LHS.getComplexFloatReal(); | |||
12568 | APFloat &B = LHS.getComplexFloatImag(); | |||
12569 | APFloat &C = RHS.getComplexFloatReal(); | |||
12570 | APFloat &D = RHS.getComplexFloatImag(); | |||
12571 | APFloat &ResR = Result.getComplexFloatReal(); | |||
12572 | APFloat &ResI = Result.getComplexFloatImag(); | |||
12573 | if (LHSReal) { | |||
12574 | assert(!RHSReal && "Cannot have two real operands for a complex op!")((!RHSReal && "Cannot have two real operands for a complex op!" ) ? static_cast<void> (0) : __assert_fail ("!RHSReal && \"Cannot have two real operands for a complex op!\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12574, __PRETTY_FUNCTION__)); | |||
12575 | ResR = A * C; | |||
12576 | ResI = A * D; | |||
12577 | } else if (RHSReal) { | |||
12578 | ResR = C * A; | |||
12579 | ResI = C * B; | |||
12580 | } else { | |||
12581 | // In the fully general case, we need to handle NaNs and infinities | |||
12582 | // robustly. | |||
12583 | APFloat AC = A * C; | |||
12584 | APFloat BD = B * D; | |||
12585 | APFloat AD = A * D; | |||
12586 | APFloat BC = B * C; | |||
12587 | ResR = AC - BD; | |||
12588 | ResI = AD + BC; | |||
12589 | if (ResR.isNaN() && ResI.isNaN()) { | |||
12590 | bool Recalc = false; | |||
12591 | if (A.isInfinity() || B.isInfinity()) { | |||
12592 | A = APFloat::copySign( | |||
12593 | APFloat(A.getSemantics(), A.isInfinity() ? 1 : 0), A); | |||
12594 | B = APFloat::copySign( | |||
12595 | APFloat(B.getSemantics(), B.isInfinity() ? 1 : 0), B); | |||
12596 | if (C.isNaN()) | |||
12597 | C = APFloat::copySign(APFloat(C.getSemantics()), C); | |||
12598 | if (D.isNaN()) | |||
12599 | D = APFloat::copySign(APFloat(D.getSemantics()), D); | |||
12600 | Recalc = true; | |||
12601 | } | |||
12602 | if (C.isInfinity() || D.isInfinity()) { | |||
12603 | C = APFloat::copySign( | |||
12604 | APFloat(C.getSemantics(), C.isInfinity() ? 1 : 0), C); | |||
12605 | D = APFloat::copySign( | |||
12606 | APFloat(D.getSemantics(), D.isInfinity() ? 1 : 0), D); | |||
12607 | if (A.isNaN()) | |||
12608 | A = APFloat::copySign(APFloat(A.getSemantics()), A); | |||
12609 | if (B.isNaN()) | |||
12610 | B = APFloat::copySign(APFloat(B.getSemantics()), B); | |||
12611 | Recalc = true; | |||
12612 | } | |||
12613 | if (!Recalc && (AC.isInfinity() || BD.isInfinity() || | |||
12614 | AD.isInfinity() || BC.isInfinity())) { | |||
12615 | if (A.isNaN()) | |||
12616 | A = APFloat::copySign(APFloat(A.getSemantics()), A); | |||
12617 | if (B.isNaN()) | |||
12618 | B = APFloat::copySign(APFloat(B.getSemantics()), B); | |||
12619 | if (C.isNaN()) | |||
12620 | C = APFloat::copySign(APFloat(C.getSemantics()), C); | |||
12621 | if (D.isNaN()) | |||
12622 | D = APFloat::copySign(APFloat(D.getSemantics()), D); | |||
12623 | Recalc = true; | |||
12624 | } | |||
12625 | if (Recalc) { | |||
12626 | ResR = APFloat::getInf(A.getSemantics()) * (A * C - B * D); | |||
12627 | ResI = APFloat::getInf(A.getSemantics()) * (A * D + B * C); | |||
12628 | } | |||
12629 | } | |||
12630 | } | |||
12631 | } else { | |||
12632 | ComplexValue LHS = Result; | |||
12633 | Result.getComplexIntReal() = | |||
12634 | (LHS.getComplexIntReal() * RHS.getComplexIntReal() - | |||
12635 | LHS.getComplexIntImag() * RHS.getComplexIntImag()); | |||
12636 | Result.getComplexIntImag() = | |||
12637 | (LHS.getComplexIntReal() * RHS.getComplexIntImag() + | |||
12638 | LHS.getComplexIntImag() * RHS.getComplexIntReal()); | |||
12639 | } | |||
12640 | break; | |||
12641 | case BO_Div: | |||
12642 | if (Result.isComplexFloat()) { | |||
12643 | // This is an implementation of complex division according to the | |||
12644 | // constraints laid out in C11 Annex G. The implementation uses the | |||
12645 | // following naming scheme: | |||
12646 | // (a + ib) / (c + id) | |||
12647 | ComplexValue LHS = Result; | |||
12648 | APFloat &A = LHS.getComplexFloatReal(); | |||
12649 | APFloat &B = LHS.getComplexFloatImag(); | |||
12650 | APFloat &C = RHS.getComplexFloatReal(); | |||
12651 | APFloat &D = RHS.getComplexFloatImag(); | |||
12652 | APFloat &ResR = Result.getComplexFloatReal(); | |||
12653 | APFloat &ResI = Result.getComplexFloatImag(); | |||
12654 | if (RHSReal) { | |||
12655 | ResR = A / C; | |||
12656 | ResI = B / C; | |||
12657 | } else { | |||
12658 | if (LHSReal) { | |||
12659 | // No real optimizations we can do here, stub out with zero. | |||
12660 | B = APFloat::getZero(A.getSemantics()); | |||
12661 | } | |||
12662 | int DenomLogB = 0; | |||
12663 | APFloat MaxCD = maxnum(abs(C), abs(D)); | |||
12664 | if (MaxCD.isFinite()) { | |||
12665 | DenomLogB = ilogb(MaxCD); | |||
12666 | C = scalbn(C, -DenomLogB, APFloat::rmNearestTiesToEven); | |||
12667 | D = scalbn(D, -DenomLogB, APFloat::rmNearestTiesToEven); | |||
12668 | } | |||
12669 | APFloat Denom = C * C + D * D; | |||
12670 | ResR = scalbn((A * C + B * D) / Denom, -DenomLogB, | |||
12671 | APFloat::rmNearestTiesToEven); | |||
12672 | ResI = scalbn((B * C - A * D) / Denom, -DenomLogB, | |||
12673 | APFloat::rmNearestTiesToEven); | |||
12674 | if (ResR.isNaN() && ResI.isNaN()) { | |||
12675 | if (Denom.isPosZero() && (!A.isNaN() || !B.isNaN())) { | |||
12676 | ResR = APFloat::getInf(ResR.getSemantics(), C.isNegative()) * A; | |||
12677 | ResI = APFloat::getInf(ResR.getSemantics(), C.isNegative()) * B; | |||
12678 | } else if ((A.isInfinity() || B.isInfinity()) && C.isFinite() && | |||
12679 | D.isFinite()) { | |||
12680 | A = APFloat::copySign( | |||
12681 | APFloat(A.getSemantics(), A.isInfinity() ? 1 : 0), A); | |||
12682 | B = APFloat::copySign( | |||
12683 | APFloat(B.getSemantics(), B.isInfinity() ? 1 : 0), B); | |||
12684 | ResR = APFloat::getInf(ResR.getSemantics()) * (A * C + B * D); | |||
12685 | ResI = APFloat::getInf(ResI.getSemantics()) * (B * C - A * D); | |||
12686 | } else if (MaxCD.isInfinity() && A.isFinite() && B.isFinite()) { | |||
12687 | C = APFloat::copySign( | |||
12688 | APFloat(C.getSemantics(), C.isInfinity() ? 1 : 0), C); | |||
12689 | D = APFloat::copySign( | |||
12690 | APFloat(D.getSemantics(), D.isInfinity() ? 1 : 0), D); | |||
12691 | ResR = APFloat::getZero(ResR.getSemantics()) * (A * C + B * D); | |||
12692 | ResI = APFloat::getZero(ResI.getSemantics()) * (B * C - A * D); | |||
12693 | } | |||
12694 | } | |||
12695 | } | |||
12696 | } else { | |||
12697 | if (RHS.getComplexIntReal() == 0 && RHS.getComplexIntImag() == 0) | |||
12698 | return Error(E, diag::note_expr_divide_by_zero); | |||
12699 | ||||
12700 | ComplexValue LHS = Result; | |||
12701 | APSInt Den = RHS.getComplexIntReal() * RHS.getComplexIntReal() + | |||
12702 | RHS.getComplexIntImag() * RHS.getComplexIntImag(); | |||
12703 | Result.getComplexIntReal() = | |||
12704 | (LHS.getComplexIntReal() * RHS.getComplexIntReal() + | |||
12705 | LHS.getComplexIntImag() * RHS.getComplexIntImag()) / Den; | |||
12706 | Result.getComplexIntImag() = | |||
12707 | (LHS.getComplexIntImag() * RHS.getComplexIntReal() - | |||
12708 | LHS.getComplexIntReal() * RHS.getComplexIntImag()) / Den; | |||
12709 | } | |||
12710 | break; | |||
12711 | } | |||
12712 | ||||
12713 | return true; | |||
12714 | } | |||
12715 | ||||
12716 | bool ComplexExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { | |||
12717 | // Get the operand value into 'Result'. | |||
12718 | if (!Visit(E->getSubExpr())) | |||
12719 | return false; | |||
12720 | ||||
12721 | switch (E->getOpcode()) { | |||
12722 | default: | |||
12723 | return Error(E); | |||
12724 | case UO_Extension: | |||
12725 | return true; | |||
12726 | case UO_Plus: | |||
12727 | // The result is always just the subexpr. | |||
12728 | return true; | |||
12729 | case UO_Minus: | |||
12730 | if (Result.isComplexFloat()) { | |||
12731 | Result.getComplexFloatReal().changeSign(); | |||
12732 | Result.getComplexFloatImag().changeSign(); | |||
12733 | } | |||
12734 | else { | |||
12735 | Result.getComplexIntReal() = -Result.getComplexIntReal(); | |||
12736 | Result.getComplexIntImag() = -Result.getComplexIntImag(); | |||
12737 | } | |||
12738 | return true; | |||
12739 | case UO_Not: | |||
12740 | if (Result.isComplexFloat()) | |||
12741 | Result.getComplexFloatImag().changeSign(); | |||
12742 | else | |||
12743 | Result.getComplexIntImag() = -Result.getComplexIntImag(); | |||
12744 | return true; | |||
12745 | } | |||
12746 | } | |||
12747 | ||||
12748 | bool ComplexExprEvaluator::VisitInitListExpr(const InitListExpr *E) { | |||
12749 | if (E->getNumInits() == 2) { | |||
12750 | if (E->getType()->isComplexType()) { | |||
12751 | Result.makeComplexFloat(); | |||
12752 | if (!EvaluateFloat(E->getInit(0), Result.FloatReal, Info)) | |||
12753 | return false; | |||
12754 | if (!EvaluateFloat(E->getInit(1), Result.FloatImag, Info)) | |||
12755 | return false; | |||
12756 | } else { | |||
12757 | Result.makeComplexInt(); | |||
12758 | if (!EvaluateInteger(E->getInit(0), Result.IntReal, Info)) | |||
12759 | return false; | |||
12760 | if (!EvaluateInteger(E->getInit(1), Result.IntImag, Info)) | |||
12761 | return false; | |||
12762 | } | |||
12763 | return true; | |||
12764 | } | |||
12765 | return ExprEvaluatorBaseTy::VisitInitListExpr(E); | |||
12766 | } | |||
12767 | ||||
12768 | //===----------------------------------------------------------------------===// | |||
12769 | // Atomic expression evaluation, essentially just handling the NonAtomicToAtomic | |||
12770 | // implicit conversion. | |||
12771 | //===----------------------------------------------------------------------===// | |||
12772 | ||||
12773 | namespace { | |||
12774 | class AtomicExprEvaluator : | |||
12775 | public ExprEvaluatorBase<AtomicExprEvaluator> { | |||
12776 | const LValue *This; | |||
12777 | APValue &Result; | |||
12778 | public: | |||
12779 | AtomicExprEvaluator(EvalInfo &Info, const LValue *This, APValue &Result) | |||
12780 | : ExprEvaluatorBaseTy(Info), This(This), Result(Result) {} | |||
12781 | ||||
12782 | bool Success(const APValue &V, const Expr *E) { | |||
12783 | Result = V; | |||
12784 | return true; | |||
12785 | } | |||
12786 | ||||
12787 | bool ZeroInitialization(const Expr *E) { | |||
12788 | ImplicitValueInitExpr VIE( | |||
12789 | E->getType()->castAs<AtomicType>()->getValueType()); | |||
12790 | // For atomic-qualified class (and array) types in C++, initialize the | |||
12791 | // _Atomic-wrapped subobject directly, in-place. | |||
12792 | return This ? EvaluateInPlace(Result, Info, *This, &VIE) | |||
12793 | : Evaluate(Result, Info, &VIE); | |||
12794 | } | |||
12795 | ||||
12796 | bool VisitCastExpr(const CastExpr *E) { | |||
12797 | switch (E->getCastKind()) { | |||
12798 | default: | |||
12799 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
12800 | case CK_NonAtomicToAtomic: | |||
12801 | return This ? EvaluateInPlace(Result, Info, *This, E->getSubExpr()) | |||
12802 | : Evaluate(Result, Info, E->getSubExpr()); | |||
12803 | } | |||
12804 | } | |||
12805 | }; | |||
12806 | } // end anonymous namespace | |||
12807 | ||||
12808 | static bool EvaluateAtomic(const Expr *E, const LValue *This, APValue &Result, | |||
12809 | EvalInfo &Info) { | |||
12810 | assert(E->isRValue() && E->getType()->isAtomicType())((E->isRValue() && E->getType()->isAtomicType ()) ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isAtomicType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12810, __PRETTY_FUNCTION__)); | |||
12811 | return AtomicExprEvaluator(Info, This, Result).Visit(E); | |||
12812 | } | |||
12813 | ||||
12814 | //===----------------------------------------------------------------------===// | |||
12815 | // Void expression evaluation, primarily for a cast to void on the LHS of a | |||
12816 | // comma operator | |||
12817 | //===----------------------------------------------------------------------===// | |||
12818 | ||||
12819 | namespace { | |||
12820 | class VoidExprEvaluator | |||
12821 | : public ExprEvaluatorBase<VoidExprEvaluator> { | |||
12822 | public: | |||
12823 | VoidExprEvaluator(EvalInfo &Info) : ExprEvaluatorBaseTy(Info) {} | |||
12824 | ||||
12825 | bool Success(const APValue &V, const Expr *e) { return true; } | |||
12826 | ||||
12827 | bool ZeroInitialization(const Expr *E) { return true; } | |||
12828 | ||||
12829 | bool VisitCastExpr(const CastExpr *E) { | |||
12830 | switch (E->getCastKind()) { | |||
12831 | default: | |||
12832 | return ExprEvaluatorBaseTy::VisitCastExpr(E); | |||
12833 | case CK_ToVoid: | |||
12834 | VisitIgnoredValue(E->getSubExpr()); | |||
12835 | return true; | |||
12836 | } | |||
12837 | } | |||
12838 | ||||
12839 | bool VisitCallExpr(const CallExpr *E) { | |||
12840 | switch (E->getBuiltinCallee()) { | |||
12841 | default: | |||
12842 | return ExprEvaluatorBaseTy::VisitCallExpr(E); | |||
12843 | case Builtin::BI__assume: | |||
12844 | case Builtin::BI__builtin_assume: | |||
12845 | // The argument is not evaluated! | |||
12846 | return true; | |||
12847 | } | |||
12848 | } | |||
12849 | ||||
12850 | bool VisitCXXDeleteExpr(const CXXDeleteExpr *E); | |||
12851 | }; | |||
12852 | } // end anonymous namespace | |||
12853 | ||||
12854 | static bool hasVirtualDestructor(QualType T) { | |||
12855 | if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) | |||
12856 | if (CXXDestructorDecl *DD = RD->getDestructor()) | |||
12857 | return DD->isVirtual(); | |||
12858 | return false; | |||
12859 | } | |||
12860 | ||||
12861 | bool VoidExprEvaluator::VisitCXXDeleteExpr(const CXXDeleteExpr *E) { | |||
12862 | // We cannot speculatively evaluate a delete expression. | |||
12863 | if (Info.SpeculativeEvaluationDepth) | |||
12864 | return false; | |||
12865 | ||||
12866 | FunctionDecl *OperatorDelete = E->getOperatorDelete(); | |||
12867 | if (!OperatorDelete->isReplaceableGlobalAllocationFunction()) { | |||
12868 | Info.FFDiag(E, diag::note_constexpr_new_non_replaceable) | |||
12869 | << isa<CXXMethodDecl>(OperatorDelete) << OperatorDelete; | |||
12870 | return false; | |||
12871 | } | |||
12872 | ||||
12873 | const Expr *Arg = E->getArgument(); | |||
12874 | ||||
12875 | LValue Pointer; | |||
12876 | if (!EvaluatePointer(Arg, Pointer, Info)) | |||
12877 | return false; | |||
12878 | if (Pointer.Designator.Invalid) | |||
12879 | return false; | |||
12880 | ||||
12881 | // Deleting a null pointer has no effect. | |||
12882 | if (Pointer.isNullPointer()) { | |||
12883 | // This is the only case where we need to produce an extension warning: | |||
12884 | // the only other way we can succeed is if we find a dynamic allocation, | |||
12885 | // and we will have warned when we allocated it in that case. | |||
12886 | if (!Info.getLangOpts().CPlusPlus2a) | |||
12887 | Info.CCEDiag(E, diag::note_constexpr_new); | |||
12888 | return true; | |||
12889 | } | |||
12890 | ||||
12891 | auto PointerAsString = [&] { | |||
12892 | APValue Printable; | |||
12893 | Pointer.moveInto(Printable); | |||
12894 | return Printable.getAsString(Info.Ctx, Arg->getType()); | |||
12895 | }; | |||
12896 | ||||
12897 | DynamicAllocLValue DA = Pointer.Base.dyn_cast<DynamicAllocLValue>(); | |||
12898 | if (!DA) { | |||
12899 | Info.FFDiag(E, diag::note_constexpr_delete_not_heap_alloc) | |||
12900 | << PointerAsString(); | |||
12901 | if (Pointer.Base) | |||
12902 | NoteLValueLocation(Info, Pointer.Base); | |||
12903 | return false; | |||
12904 | } | |||
12905 | QualType AllocType = Pointer.Base.getDynamicAllocType(); | |||
12906 | ||||
12907 | Optional<EvalInfo::DynAlloc*> Alloc = Info.lookupDynamicAlloc(DA); | |||
12908 | if (!Alloc) { | |||
12909 | Info.FFDiag(E, diag::note_constexpr_double_delete); | |||
12910 | return false; | |||
12911 | } | |||
12912 | ||||
12913 | if (E->isArrayForm() != AllocType->isConstantArrayType()) { | |||
12914 | Info.FFDiag(E, diag::note_constexpr_new_delete_mismatch) | |||
12915 | << E->isArrayForm() << AllocType; | |||
12916 | NoteLValueLocation(Info, Pointer.Base); | |||
12917 | return false; | |||
12918 | } | |||
12919 | ||||
12920 | bool Subobject = false; | |||
12921 | if (E->isArrayForm()) { | |||
12922 | Subobject = Pointer.Designator.Entries.size() != 1 || | |||
12923 | Pointer.Designator.Entries[0].getAsArrayIndex() != 0; | |||
12924 | } else { | |||
12925 | Subobject = Pointer.Designator.MostDerivedPathLength != 0 || | |||
12926 | Pointer.Designator.isOnePastTheEnd(); | |||
12927 | } | |||
12928 | if (Subobject) { | |||
12929 | Info.FFDiag(E, diag::note_constexpr_delete_subobject) | |||
12930 | << PointerAsString() << Pointer.Designator.isOnePastTheEnd(); | |||
12931 | return false; | |||
12932 | } | |||
12933 | ||||
12934 | // For the non-array case, the designator must be empty if the static type | |||
12935 | // does not have a virtual destructor. | |||
12936 | if (!E->isArrayForm() && Pointer.Designator.Entries.size() != 0 && | |||
12937 | !hasVirtualDestructor(Arg->getType()->getPointeeType())) { | |||
12938 | Info.FFDiag(E, diag::note_constexpr_delete_base_nonvirt_dtor) | |||
12939 | << Arg->getType()->getPointeeType() << AllocType; | |||
12940 | return false; | |||
12941 | } | |||
12942 | ||||
12943 | if (!HandleDestruction(Info, E->getExprLoc(), Pointer.getLValueBase(), | |||
12944 | (*Alloc)->Value, AllocType)) | |||
12945 | return false; | |||
12946 | ||||
12947 | if (!Info.HeapAllocs.erase(DA)) { | |||
12948 | // The element was already erased. This means the destructor call also | |||
12949 | // deleted the object. | |||
12950 | // FIXME: This probably results in undefined behavior before we get this | |||
12951 | // far, and should be diagnosed elsewhere first. | |||
12952 | Info.FFDiag(E, diag::note_constexpr_double_delete); | |||
12953 | return false; | |||
12954 | } | |||
12955 | ||||
12956 | return true; | |||
12957 | } | |||
12958 | ||||
12959 | static bool EvaluateVoid(const Expr *E, EvalInfo &Info) { | |||
12960 | assert(E->isRValue() && E->getType()->isVoidType())((E->isRValue() && E->getType()->isVoidType( )) ? static_cast<void> (0) : __assert_fail ("E->isRValue() && E->getType()->isVoidType()" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 12960, __PRETTY_FUNCTION__)); | |||
12961 | return VoidExprEvaluator(Info).Visit(E); | |||
12962 | } | |||
12963 | ||||
12964 | //===----------------------------------------------------------------------===// | |||
12965 | // Top level Expr::EvaluateAsRValue method. | |||
12966 | //===----------------------------------------------------------------------===// | |||
12967 | ||||
12968 | static bool Evaluate(APValue &Result, EvalInfo &Info, const Expr *E) { | |||
12969 | // In C, function designators are not lvalues, but we evaluate them as if they | |||
12970 | // are. | |||
12971 | QualType T = E->getType(); | |||
12972 | if (E->isGLValue() || T->isFunctionType()) { | |||
12973 | LValue LV; | |||
12974 | if (!EvaluateLValue(E, LV, Info)) | |||
12975 | return false; | |||
12976 | LV.moveInto(Result); | |||
12977 | } else if (T->isVectorType()) { | |||
12978 | if (!EvaluateVector(E, Result, Info)) | |||
12979 | return false; | |||
12980 | } else if (T->isIntegralOrEnumerationType()) { | |||
12981 | if (!IntExprEvaluator(Info, Result).Visit(E)) | |||
12982 | return false; | |||
12983 | } else if (T->hasPointerRepresentation()) { | |||
12984 | LValue LV; | |||
12985 | if (!EvaluatePointer(E, LV, Info)) | |||
12986 | return false; | |||
12987 | LV.moveInto(Result); | |||
12988 | } else if (T->isRealFloatingType()) { | |||
12989 | llvm::APFloat F(0.0); | |||
12990 | if (!EvaluateFloat(E, F, Info)) | |||
12991 | return false; | |||
12992 | Result = APValue(F); | |||
12993 | } else if (T->isAnyComplexType()) { | |||
12994 | ComplexValue C; | |||
12995 | if (!EvaluateComplex(E, C, Info)) | |||
12996 | return false; | |||
12997 | C.moveInto(Result); | |||
12998 | } else if (T->isFixedPointType()) { | |||
12999 | if (!FixedPointExprEvaluator(Info, Result).Visit(E)) return false; | |||
13000 | } else if (T->isMemberPointerType()) { | |||
13001 | MemberPtr P; | |||
13002 | if (!EvaluateMemberPointer(E, P, Info)) | |||
13003 | return false; | |||
13004 | P.moveInto(Result); | |||
13005 | return true; | |||
13006 | } else if (T->isArrayType()) { | |||
13007 | LValue LV; | |||
13008 | APValue &Value = | |||
13009 | Info.CurrentCall->createTemporary(E, T, false, LV); | |||
13010 | if (!EvaluateArray(E, LV, Value, Info)) | |||
13011 | return false; | |||
13012 | Result = Value; | |||
13013 | } else if (T->isRecordType()) { | |||
13014 | LValue LV; | |||
13015 | APValue &Value = Info.CurrentCall->createTemporary(E, T, false, LV); | |||
13016 | if (!EvaluateRecord(E, LV, Value, Info)) | |||
13017 | return false; | |||
13018 | Result = Value; | |||
13019 | } else if (T->isVoidType()) { | |||
13020 | if (!Info.getLangOpts().CPlusPlus11) | |||
13021 | Info.CCEDiag(E, diag::note_constexpr_nonliteral) | |||
13022 | << E->getType(); | |||
13023 | if (!EvaluateVoid(E, Info)) | |||
13024 | return false; | |||
13025 | } else if (T->isAtomicType()) { | |||
13026 | QualType Unqual = T.getAtomicUnqualifiedType(); | |||
13027 | if (Unqual->isArrayType() || Unqual->isRecordType()) { | |||
13028 | LValue LV; | |||
13029 | APValue &Value = Info.CurrentCall->createTemporary(E, Unqual, false, LV); | |||
13030 | if (!EvaluateAtomic(E, &LV, Value, Info)) | |||
13031 | return false; | |||
13032 | } else { | |||
13033 | if (!EvaluateAtomic(E, nullptr, Result, Info)) | |||
13034 | return false; | |||
13035 | } | |||
13036 | } else if (Info.getLangOpts().CPlusPlus11) { | |||
13037 | Info.FFDiag(E, diag::note_constexpr_nonliteral) << E->getType(); | |||
13038 | return false; | |||
13039 | } else { | |||
13040 | Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr); | |||
13041 | return false; | |||
13042 | } | |||
13043 | ||||
13044 | return true; | |||
13045 | } | |||
13046 | ||||
13047 | /// EvaluateInPlace - Evaluate an expression in-place in an APValue. In some | |||
13048 | /// cases, the in-place evaluation is essential, since later initializers for | |||
13049 | /// an object can indirectly refer to subobjects which were initialized earlier. | |||
13050 | static bool EvaluateInPlace(APValue &Result, EvalInfo &Info, const LValue &This, | |||
13051 | const Expr *E, bool AllowNonLiteralTypes) { | |||
13052 | assert(!E->isValueDependent())((!E->isValueDependent()) ? static_cast<void> (0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13052, __PRETTY_FUNCTION__)); | |||
13053 | ||||
13054 | if (!AllowNonLiteralTypes && !CheckLiteralType(Info, E, &This)) | |||
13055 | return false; | |||
13056 | ||||
13057 | if (E->isRValue()) { | |||
13058 | // Evaluate arrays and record types in-place, so that later initializers can | |||
13059 | // refer to earlier-initialized members of the object. | |||
13060 | QualType T = E->getType(); | |||
13061 | if (T->isArrayType()) | |||
13062 | return EvaluateArray(E, This, Result, Info); | |||
13063 | else if (T->isRecordType()) | |||
13064 | return EvaluateRecord(E, This, Result, Info); | |||
13065 | else if (T->isAtomicType()) { | |||
13066 | QualType Unqual = T.getAtomicUnqualifiedType(); | |||
13067 | if (Unqual->isArrayType() || Unqual->isRecordType()) | |||
13068 | return EvaluateAtomic(E, &This, Result, Info); | |||
13069 | } | |||
13070 | } | |||
13071 | ||||
13072 | // For any other type, in-place evaluation is unimportant. | |||
13073 | return Evaluate(Result, Info, E); | |||
13074 | } | |||
13075 | ||||
13076 | /// EvaluateAsRValue - Try to evaluate this expression, performing an implicit | |||
13077 | /// lvalue-to-rvalue cast if it is an lvalue. | |||
13078 | static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result) { | |||
13079 | if (Info.EnableNewConstInterp) { | |||
13080 | auto &InterpCtx = Info.Ctx.getInterpContext(); | |||
13081 | switch (InterpCtx.evaluateAsRValue(Info, E, Result)) { | |||
13082 | case interp::InterpResult::Success: | |||
13083 | return true; | |||
13084 | case interp::InterpResult::Fail: | |||
13085 | return false; | |||
13086 | case interp::InterpResult::Bail: | |||
13087 | break; | |||
13088 | } | |||
13089 | } | |||
13090 | ||||
13091 | if (E->getType().isNull()) | |||
13092 | return false; | |||
13093 | ||||
13094 | if (!CheckLiteralType(Info, E)) | |||
13095 | return false; | |||
13096 | ||||
13097 | if (!::Evaluate(Result, Info, E)) | |||
13098 | return false; | |||
13099 | ||||
13100 | if (E->isGLValue()) { | |||
13101 | LValue LV; | |||
13102 | LV.setFrom(Info.Ctx, Result); | |||
13103 | if (!handleLValueToRValueConversion(Info, E, E->getType(), LV, Result)) | |||
13104 | return false; | |||
13105 | } | |||
13106 | ||||
13107 | // Check this core constant expression is a constant expression. | |||
13108 | return CheckConstantExpression(Info, E->getExprLoc(), E->getType(), Result) && | |||
13109 | CheckMemoryLeaks(Info); | |||
13110 | } | |||
13111 | ||||
13112 | static bool FastEvaluateAsRValue(const Expr *Exp, Expr::EvalResult &Result, | |||
13113 | const ASTContext &Ctx, bool &IsConst) { | |||
13114 | // Fast-path evaluations of integer literals, since we sometimes see files | |||
13115 | // containing vast quantities of these. | |||
13116 | if (const IntegerLiteral *L = dyn_cast<IntegerLiteral>(Exp)) { | |||
13117 | Result.Val = APValue(APSInt(L->getValue(), | |||
13118 | L->getType()->isUnsignedIntegerType())); | |||
13119 | IsConst = true; | |||
13120 | return true; | |||
13121 | } | |||
13122 | ||||
13123 | // This case should be rare, but we need to check it before we check on | |||
13124 | // the type below. | |||
13125 | if (Exp->getType().isNull()) { | |||
13126 | IsConst = false; | |||
13127 | return true; | |||
13128 | } | |||
13129 | ||||
13130 | // FIXME: Evaluating values of large array and record types can cause | |||
13131 | // performance problems. Only do so in C++11 for now. | |||
13132 | if (Exp->isRValue() && (Exp->getType()->isArrayType() || | |||
13133 | Exp->getType()->isRecordType()) && | |||
13134 | !Ctx.getLangOpts().CPlusPlus11) { | |||
13135 | IsConst = false; | |||
13136 | return true; | |||
13137 | } | |||
13138 | return false; | |||
13139 | } | |||
13140 | ||||
13141 | static bool hasUnacceptableSideEffect(Expr::EvalStatus &Result, | |||
13142 | Expr::SideEffectsKind SEK) { | |||
13143 | return (SEK < Expr::SE_AllowSideEffects && Result.HasSideEffects) || | |||
13144 | (SEK < Expr::SE_AllowUndefinedBehavior && Result.HasUndefinedBehavior); | |||
13145 | } | |||
13146 | ||||
13147 | static bool EvaluateAsRValue(const Expr *E, Expr::EvalResult &Result, | |||
13148 | const ASTContext &Ctx, EvalInfo &Info) { | |||
13149 | bool IsConst; | |||
13150 | if (FastEvaluateAsRValue(E, Result, Ctx, IsConst)) | |||
13151 | return IsConst; | |||
13152 | ||||
13153 | return EvaluateAsRValue(Info, E, Result.Val); | |||
13154 | } | |||
13155 | ||||
13156 | static bool EvaluateAsInt(const Expr *E, Expr::EvalResult &ExprResult, | |||
13157 | const ASTContext &Ctx, | |||
13158 | Expr::SideEffectsKind AllowSideEffects, | |||
13159 | EvalInfo &Info) { | |||
13160 | if (!E->getType()->isIntegralOrEnumerationType()) | |||
13161 | return false; | |||
13162 | ||||
13163 | if (!::EvaluateAsRValue(E, ExprResult, Ctx, Info) || | |||
13164 | !ExprResult.Val.isInt() || | |||
13165 | hasUnacceptableSideEffect(ExprResult, AllowSideEffects)) | |||
13166 | return false; | |||
13167 | ||||
13168 | return true; | |||
13169 | } | |||
13170 | ||||
13171 | static bool EvaluateAsFixedPoint(const Expr *E, Expr::EvalResult &ExprResult, | |||
13172 | const ASTContext &Ctx, | |||
13173 | Expr::SideEffectsKind AllowSideEffects, | |||
13174 | EvalInfo &Info) { | |||
13175 | if (!E->getType()->isFixedPointType()) | |||
13176 | return false; | |||
13177 | ||||
13178 | if (!::EvaluateAsRValue(E, ExprResult, Ctx, Info)) | |||
13179 | return false; | |||
13180 | ||||
13181 | if (!ExprResult.Val.isFixedPoint() || | |||
13182 | hasUnacceptableSideEffect(ExprResult, AllowSideEffects)) | |||
13183 | return false; | |||
13184 | ||||
13185 | return true; | |||
13186 | } | |||
13187 | ||||
13188 | /// EvaluateAsRValue - Return true if this is a constant which we can fold using | |||
13189 | /// any crazy technique (that has nothing to do with language standards) that | |||
13190 | /// we want to. If this function returns true, it returns the folded constant | |||
13191 | /// in Result. If this expression is a glvalue, an lvalue-to-rvalue conversion | |||
13192 | /// will be applied to the result. | |||
13193 | bool Expr::EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx, | |||
13194 | bool InConstantContext) const { | |||
13195 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13196, __PRETTY_FUNCTION__)) | |||
13196 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13196, __PRETTY_FUNCTION__)); | |||
13197 | EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects); | |||
13198 | Info.InConstantContext = InConstantContext; | |||
13199 | return ::EvaluateAsRValue(this, Result, Ctx, Info); | |||
13200 | } | |||
13201 | ||||
13202 | bool Expr::EvaluateAsBooleanCondition(bool &Result, const ASTContext &Ctx, | |||
13203 | bool InConstantContext) const { | |||
13204 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13205, __PRETTY_FUNCTION__)) | |||
13205 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13205, __PRETTY_FUNCTION__)); | |||
13206 | EvalResult Scratch; | |||
13207 | return EvaluateAsRValue(Scratch, Ctx, InConstantContext) && | |||
13208 | HandleConversionToBool(Scratch.Val, Result); | |||
13209 | } | |||
13210 | ||||
13211 | bool Expr::EvaluateAsInt(EvalResult &Result, const ASTContext &Ctx, | |||
13212 | SideEffectsKind AllowSideEffects, | |||
13213 | bool InConstantContext) const { | |||
13214 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13215, __PRETTY_FUNCTION__)) | |||
13215 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13215, __PRETTY_FUNCTION__)); | |||
13216 | EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects); | |||
13217 | Info.InConstantContext = InConstantContext; | |||
13218 | return ::EvaluateAsInt(this, Result, Ctx, AllowSideEffects, Info); | |||
13219 | } | |||
13220 | ||||
13221 | bool Expr::EvaluateAsFixedPoint(EvalResult &Result, const ASTContext &Ctx, | |||
13222 | SideEffectsKind AllowSideEffects, | |||
13223 | bool InConstantContext) const { | |||
13224 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13225, __PRETTY_FUNCTION__)) | |||
13225 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13225, __PRETTY_FUNCTION__)); | |||
13226 | EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects); | |||
13227 | Info.InConstantContext = InConstantContext; | |||
13228 | return ::EvaluateAsFixedPoint(this, Result, Ctx, AllowSideEffects, Info); | |||
13229 | } | |||
13230 | ||||
13231 | bool Expr::EvaluateAsFloat(APFloat &Result, const ASTContext &Ctx, | |||
13232 | SideEffectsKind AllowSideEffects, | |||
13233 | bool InConstantContext) const { | |||
13234 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13235, __PRETTY_FUNCTION__)) | |||
13235 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13235, __PRETTY_FUNCTION__)); | |||
13236 | ||||
13237 | if (!getType()->isRealFloatingType()) | |||
13238 | return false; | |||
13239 | ||||
13240 | EvalResult ExprResult; | |||
13241 | if (!EvaluateAsRValue(ExprResult, Ctx, InConstantContext) || | |||
13242 | !ExprResult.Val.isFloat() || | |||
13243 | hasUnacceptableSideEffect(ExprResult, AllowSideEffects)) | |||
13244 | return false; | |||
13245 | ||||
13246 | Result = ExprResult.Val.getFloat(); | |||
13247 | return true; | |||
13248 | } | |||
13249 | ||||
13250 | bool Expr::EvaluateAsLValue(EvalResult &Result, const ASTContext &Ctx, | |||
13251 | bool InConstantContext) const { | |||
13252 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13253, __PRETTY_FUNCTION__)) | |||
13253 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13253, __PRETTY_FUNCTION__)); | |||
13254 | ||||
13255 | EvalInfo Info(Ctx, Result, EvalInfo::EM_ConstantFold); | |||
13256 | Info.InConstantContext = InConstantContext; | |||
13257 | LValue LV; | |||
13258 | CheckedTemporaries CheckedTemps; | |||
13259 | if (!EvaluateLValue(this, LV, Info) || !Info.discardCleanups() || | |||
13260 | Result.HasSideEffects || | |||
13261 | !CheckLValueConstantExpression(Info, getExprLoc(), | |||
13262 | Ctx.getLValueReferenceType(getType()), LV, | |||
13263 | Expr::EvaluateForCodeGen, CheckedTemps)) | |||
13264 | return false; | |||
13265 | ||||
13266 | LV.moveInto(Result.Val); | |||
13267 | return true; | |||
13268 | } | |||
13269 | ||||
13270 | bool Expr::EvaluateAsConstantExpr(EvalResult &Result, ConstExprUsage Usage, | |||
13271 | const ASTContext &Ctx) const { | |||
13272 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13273, __PRETTY_FUNCTION__)) | |||
13273 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13273, __PRETTY_FUNCTION__)); | |||
13274 | ||||
13275 | EvalInfo::EvaluationMode EM = EvalInfo::EM_ConstantExpression; | |||
13276 | EvalInfo Info(Ctx, Result, EM); | |||
13277 | Info.InConstantContext = true; | |||
13278 | ||||
13279 | if (!::Evaluate(Result.Val, Info, this) || Result.HasSideEffects) | |||
13280 | return false; | |||
13281 | ||||
13282 | if (!Info.discardCleanups()) | |||
13283 | llvm_unreachable("Unhandled cleanup; missing full expression marker?")::llvm::llvm_unreachable_internal("Unhandled cleanup; missing full expression marker?" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13283); | |||
13284 | ||||
13285 | return CheckConstantExpression(Info, getExprLoc(), getType(), Result.Val, | |||
13286 | Usage) && | |||
13287 | CheckMemoryLeaks(Info); | |||
13288 | } | |||
13289 | ||||
13290 | bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx, | |||
13291 | const VarDecl *VD, | |||
13292 | SmallVectorImpl<PartialDiagnosticAt> &Notes) const { | |||
13293 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13294, __PRETTY_FUNCTION__)) | |||
13294 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13294, __PRETTY_FUNCTION__)); | |||
13295 | ||||
13296 | // FIXME: Evaluating initializers for large array and record types can cause | |||
13297 | // performance problems. Only do so in C++11 for now. | |||
13298 | if (isRValue() && (getType()->isArrayType() || getType()->isRecordType()) && | |||
13299 | !Ctx.getLangOpts().CPlusPlus11) | |||
13300 | return false; | |||
13301 | ||||
13302 | Expr::EvalStatus EStatus; | |||
13303 | EStatus.Diag = &Notes; | |||
13304 | ||||
13305 | EvalInfo Info(Ctx, EStatus, VD->isConstexpr() | |||
13306 | ? EvalInfo::EM_ConstantExpression | |||
13307 | : EvalInfo::EM_ConstantFold); | |||
13308 | Info.setEvaluatingDecl(VD, Value); | |||
13309 | Info.InConstantContext = true; | |||
13310 | ||||
13311 | SourceLocation DeclLoc = VD->getLocation(); | |||
13312 | QualType DeclTy = VD->getType(); | |||
13313 | ||||
13314 | if (Info.EnableNewConstInterp) { | |||
13315 | auto &InterpCtx = const_cast<ASTContext &>(Ctx).getInterpContext(); | |||
13316 | switch (InterpCtx.evaluateAsInitializer(Info, VD, Value)) { | |||
13317 | case interp::InterpResult::Fail: | |||
13318 | // Bail out if an error was encountered. | |||
13319 | return false; | |||
13320 | case interp::InterpResult::Success: | |||
13321 | // Evaluation succeeded and value was set. | |||
13322 | return CheckConstantExpression(Info, DeclLoc, DeclTy, Value); | |||
13323 | case interp::InterpResult::Bail: | |||
13324 | // Evaluate the value again for the tree evaluator to use. | |||
13325 | break; | |||
13326 | } | |||
13327 | } | |||
13328 | ||||
13329 | LValue LVal; | |||
13330 | LVal.set(VD); | |||
13331 | ||||
13332 | // C++11 [basic.start.init]p2: | |||
13333 | // Variables with static storage duration or thread storage duration shall be | |||
13334 | // zero-initialized before any other initialization takes place. | |||
13335 | // This behavior is not present in C. | |||
13336 | if (Ctx.getLangOpts().CPlusPlus && !VD->hasLocalStorage() && | |||
13337 | !DeclTy->isReferenceType()) { | |||
13338 | ImplicitValueInitExpr VIE(DeclTy); | |||
13339 | if (!EvaluateInPlace(Value, Info, LVal, &VIE, | |||
13340 | /*AllowNonLiteralTypes=*/true)) | |||
13341 | return false; | |||
13342 | } | |||
13343 | ||||
13344 | if (!EvaluateInPlace(Value, Info, LVal, this, | |||
13345 | /*AllowNonLiteralTypes=*/true) || | |||
13346 | EStatus.HasSideEffects) | |||
13347 | return false; | |||
13348 | ||||
13349 | // At this point, any lifetime-extended temporaries are completely | |||
13350 | // initialized. | |||
13351 | Info.performLifetimeExtension(); | |||
13352 | ||||
13353 | if (!Info.discardCleanups()) | |||
13354 | llvm_unreachable("Unhandled cleanup; missing full expression marker?")::llvm::llvm_unreachable_internal("Unhandled cleanup; missing full expression marker?" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13354); | |||
13355 | ||||
13356 | return CheckConstantExpression(Info, DeclLoc, DeclTy, Value) && | |||
13357 | CheckMemoryLeaks(Info); | |||
13358 | } | |||
13359 | ||||
13360 | bool VarDecl::evaluateDestruction( | |||
13361 | SmallVectorImpl<PartialDiagnosticAt> &Notes) const { | |||
13362 | assert(getEvaluatedValue() && !getEvaluatedValue()->isAbsent() &&((getEvaluatedValue() && !getEvaluatedValue()->isAbsent () && "cannot evaluate destruction of non-constant-initialized variable" ) ? static_cast<void> (0) : __assert_fail ("getEvaluatedValue() && !getEvaluatedValue()->isAbsent() && \"cannot evaluate destruction of non-constant-initialized variable\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13363, __PRETTY_FUNCTION__)) | |||
13363 | "cannot evaluate destruction of non-constant-initialized variable")((getEvaluatedValue() && !getEvaluatedValue()->isAbsent () && "cannot evaluate destruction of non-constant-initialized variable" ) ? static_cast<void> (0) : __assert_fail ("getEvaluatedValue() && !getEvaluatedValue()->isAbsent() && \"cannot evaluate destruction of non-constant-initialized variable\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13363, __PRETTY_FUNCTION__)); | |||
13364 | ||||
13365 | Expr::EvalStatus EStatus; | |||
13366 | EStatus.Diag = &Notes; | |||
13367 | ||||
13368 | // Make a copy of the value for the destructor to mutate. | |||
13369 | APValue DestroyedValue = *getEvaluatedValue(); | |||
13370 | ||||
13371 | EvalInfo Info(getASTContext(), EStatus, EvalInfo::EM_ConstantExpression); | |||
13372 | Info.setEvaluatingDecl(this, DestroyedValue, | |||
13373 | EvalInfo::EvaluatingDeclKind::Dtor); | |||
13374 | Info.InConstantContext = true; | |||
13375 | ||||
13376 | SourceLocation DeclLoc = getLocation(); | |||
13377 | QualType DeclTy = getType(); | |||
13378 | ||||
13379 | LValue LVal; | |||
13380 | LVal.set(this); | |||
13381 | ||||
13382 | // FIXME: Consider storing whether this variable has constant destruction in | |||
13383 | // the EvaluatedStmt so that CodeGen can query it. | |||
13384 | if (!HandleDestruction(Info, DeclLoc, LVal.Base, DestroyedValue, DeclTy) || | |||
13385 | EStatus.HasSideEffects) | |||
13386 | return false; | |||
13387 | ||||
13388 | if (!Info.discardCleanups()) | |||
13389 | llvm_unreachable("Unhandled cleanup; missing full expression marker?")::llvm::llvm_unreachable_internal("Unhandled cleanup; missing full expression marker?" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13389); | |||
13390 | ||||
13391 | ensureEvaluatedStmt()->HasConstantDestruction = true; | |||
13392 | return true; | |||
13393 | } | |||
13394 | ||||
13395 | /// isEvaluatable - Call EvaluateAsRValue to see if this expression can be | |||
13396 | /// constant folded, but discard the result. | |||
13397 | bool Expr::isEvaluatable(const ASTContext &Ctx, SideEffectsKind SEK) const { | |||
13398 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13399, __PRETTY_FUNCTION__)) | |||
13399 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13399, __PRETTY_FUNCTION__)); | |||
13400 | ||||
13401 | EvalResult Result; | |||
13402 | return EvaluateAsRValue(Result, Ctx, /* in constant context */ true) && | |||
13403 | !hasUnacceptableSideEffect(Result, SEK); | |||
13404 | } | |||
13405 | ||||
13406 | APSInt Expr::EvaluateKnownConstInt(const ASTContext &Ctx, | |||
13407 | SmallVectorImpl<PartialDiagnosticAt> *Diag) const { | |||
13408 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13409, __PRETTY_FUNCTION__)) | |||
13409 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13409, __PRETTY_FUNCTION__)); | |||
13410 | ||||
13411 | EvalResult EVResult; | |||
13412 | EVResult.Diag = Diag; | |||
13413 | EvalInfo Info(Ctx, EVResult, EvalInfo::EM_IgnoreSideEffects); | |||
13414 | Info.InConstantContext = true; | |||
13415 | ||||
13416 | bool Result = ::EvaluateAsRValue(this, EVResult, Ctx, Info); | |||
13417 | (void)Result; | |||
13418 | assert(Result && "Could not evaluate expression")((Result && "Could not evaluate expression") ? static_cast <void> (0) : __assert_fail ("Result && \"Could not evaluate expression\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13418, __PRETTY_FUNCTION__)); | |||
13419 | assert(EVResult.Val.isInt() && "Expression did not evaluate to integer")((EVResult.Val.isInt() && "Expression did not evaluate to integer" ) ? static_cast<void> (0) : __assert_fail ("EVResult.Val.isInt() && \"Expression did not evaluate to integer\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13419, __PRETTY_FUNCTION__)); | |||
13420 | ||||
13421 | return EVResult.Val.getInt(); | |||
13422 | } | |||
13423 | ||||
13424 | APSInt Expr::EvaluateKnownConstIntCheckOverflow( | |||
13425 | const ASTContext &Ctx, SmallVectorImpl<PartialDiagnosticAt> *Diag) const { | |||
13426 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13427, __PRETTY_FUNCTION__)) | |||
13427 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13427, __PRETTY_FUNCTION__)); | |||
13428 | ||||
13429 | EvalResult EVResult; | |||
13430 | EVResult.Diag = Diag; | |||
13431 | EvalInfo Info(Ctx, EVResult, EvalInfo::EM_IgnoreSideEffects); | |||
13432 | Info.InConstantContext = true; | |||
13433 | Info.CheckingForUndefinedBehavior = true; | |||
13434 | ||||
13435 | bool Result = ::EvaluateAsRValue(Info, this, EVResult.Val); | |||
13436 | (void)Result; | |||
13437 | assert(Result && "Could not evaluate expression")((Result && "Could not evaluate expression") ? static_cast <void> (0) : __assert_fail ("Result && \"Could not evaluate expression\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13437, __PRETTY_FUNCTION__)); | |||
13438 | assert(EVResult.Val.isInt() && "Expression did not evaluate to integer")((EVResult.Val.isInt() && "Expression did not evaluate to integer" ) ? static_cast<void> (0) : __assert_fail ("EVResult.Val.isInt() && \"Expression did not evaluate to integer\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13438, __PRETTY_FUNCTION__)); | |||
13439 | ||||
13440 | return EVResult.Val.getInt(); | |||
13441 | } | |||
13442 | ||||
13443 | void Expr::EvaluateForOverflow(const ASTContext &Ctx) const { | |||
13444 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13445, __PRETTY_FUNCTION__)) | |||
13445 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13445, __PRETTY_FUNCTION__)); | |||
13446 | ||||
13447 | bool IsConst; | |||
13448 | EvalResult EVResult; | |||
13449 | if (!FastEvaluateAsRValue(this, EVResult, Ctx, IsConst)) { | |||
13450 | EvalInfo Info(Ctx, EVResult, EvalInfo::EM_IgnoreSideEffects); | |||
13451 | Info.CheckingForUndefinedBehavior = true; | |||
13452 | (void)::EvaluateAsRValue(Info, this, EVResult.Val); | |||
13453 | } | |||
13454 | } | |||
13455 | ||||
13456 | bool Expr::EvalResult::isGlobalLValue() const { | |||
13457 | assert(Val.isLValue())((Val.isLValue()) ? static_cast<void> (0) : __assert_fail ("Val.isLValue()", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13457, __PRETTY_FUNCTION__)); | |||
13458 | return IsGlobalLValue(Val.getLValueBase()); | |||
13459 | } | |||
13460 | ||||
13461 | ||||
13462 | /// isIntegerConstantExpr - this recursive routine will test if an expression is | |||
13463 | /// an integer constant expression. | |||
13464 | ||||
13465 | /// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero, | |||
13466 | /// comma, etc | |||
13467 | ||||
13468 | // CheckICE - This function does the fundamental ICE checking: the returned | |||
13469 | // ICEDiag contains an ICEKind indicating whether the expression is an ICE, | |||
13470 | // and a (possibly null) SourceLocation indicating the location of the problem. | |||
13471 | // | |||
13472 | // Note that to reduce code duplication, this helper does no evaluation | |||
13473 | // itself; the caller checks whether the expression is evaluatable, and | |||
13474 | // in the rare cases where CheckICE actually cares about the evaluated | |||
13475 | // value, it calls into Evaluate. | |||
13476 | ||||
13477 | namespace { | |||
13478 | ||||
13479 | enum ICEKind { | |||
13480 | /// This expression is an ICE. | |||
13481 | IK_ICE, | |||
13482 | /// This expression is not an ICE, but if it isn't evaluated, it's | |||
13483 | /// a legal subexpression for an ICE. This return value is used to handle | |||
13484 | /// the comma operator in C99 mode, and non-constant subexpressions. | |||
13485 | IK_ICEIfUnevaluated, | |||
13486 | /// This expression is not an ICE, and is not a legal subexpression for one. | |||
13487 | IK_NotICE | |||
13488 | }; | |||
13489 | ||||
13490 | struct ICEDiag { | |||
13491 | ICEKind Kind; | |||
13492 | SourceLocation Loc; | |||
13493 | ||||
13494 | ICEDiag(ICEKind IK, SourceLocation l) : Kind(IK), Loc(l) {} | |||
13495 | }; | |||
13496 | ||||
13497 | } | |||
13498 | ||||
13499 | static ICEDiag NoDiag() { return ICEDiag(IK_ICE, SourceLocation()); } | |||
13500 | ||||
13501 | static ICEDiag Worst(ICEDiag A, ICEDiag B) { return A.Kind >= B.Kind ? A : B; } | |||
13502 | ||||
13503 | static ICEDiag CheckEvalInICE(const Expr* E, const ASTContext &Ctx) { | |||
13504 | Expr::EvalResult EVResult; | |||
13505 | Expr::EvalStatus Status; | |||
13506 | EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpression); | |||
13507 | ||||
13508 | Info.InConstantContext = true; | |||
13509 | if (!::EvaluateAsRValue(E, EVResult, Ctx, Info) || EVResult.HasSideEffects || | |||
13510 | !EVResult.Val.isInt()) | |||
13511 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13512 | ||||
13513 | return NoDiag(); | |||
13514 | } | |||
13515 | ||||
13516 | static ICEDiag CheckICE(const Expr* E, const ASTContext &Ctx) { | |||
13517 | assert(!E->isValueDependent() && "Should not see value dependent exprs!")((!E->isValueDependent() && "Should not see value dependent exprs!" ) ? static_cast<void> (0) : __assert_fail ("!E->isValueDependent() && \"Should not see value dependent exprs!\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13517, __PRETTY_FUNCTION__)); | |||
13518 | if (!E->getType()->isIntegralOrEnumerationType()) | |||
13519 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13520 | ||||
13521 | switch (E->getStmtClass()) { | |||
13522 | #define ABSTRACT_STMT(Node) | |||
13523 | #define STMT(Node, Base) case Expr::Node##Class: | |||
13524 | #define EXPR(Node, Base) | |||
13525 | #include "clang/AST/StmtNodes.inc" | |||
13526 | case Expr::PredefinedExprClass: | |||
13527 | case Expr::FloatingLiteralClass: | |||
13528 | case Expr::ImaginaryLiteralClass: | |||
13529 | case Expr::StringLiteralClass: | |||
13530 | case Expr::ArraySubscriptExprClass: | |||
13531 | case Expr::OMPArraySectionExprClass: | |||
13532 | case Expr::MemberExprClass: | |||
13533 | case Expr::CompoundAssignOperatorClass: | |||
13534 | case Expr::CompoundLiteralExprClass: | |||
13535 | case Expr::ExtVectorElementExprClass: | |||
13536 | case Expr::DesignatedInitExprClass: | |||
13537 | case Expr::ArrayInitLoopExprClass: | |||
13538 | case Expr::ArrayInitIndexExprClass: | |||
13539 | case Expr::NoInitExprClass: | |||
13540 | case Expr::DesignatedInitUpdateExprClass: | |||
13541 | case Expr::ImplicitValueInitExprClass: | |||
13542 | case Expr::ParenListExprClass: | |||
13543 | case Expr::VAArgExprClass: | |||
13544 | case Expr::AddrLabelExprClass: | |||
13545 | case Expr::StmtExprClass: | |||
13546 | case Expr::CXXMemberCallExprClass: | |||
13547 | case Expr::CUDAKernelCallExprClass: | |||
13548 | case Expr::CXXDynamicCastExprClass: | |||
13549 | case Expr::CXXTypeidExprClass: | |||
13550 | case Expr::CXXUuidofExprClass: | |||
13551 | case Expr::MSPropertyRefExprClass: | |||
13552 | case Expr::MSPropertySubscriptExprClass: | |||
13553 | case Expr::CXXNullPtrLiteralExprClass: | |||
13554 | case Expr::UserDefinedLiteralClass: | |||
13555 | case Expr::CXXThisExprClass: | |||
13556 | case Expr::CXXThrowExprClass: | |||
13557 | case Expr::CXXNewExprClass: | |||
13558 | case Expr::CXXDeleteExprClass: | |||
13559 | case Expr::CXXPseudoDestructorExprClass: | |||
13560 | case Expr::UnresolvedLookupExprClass: | |||
13561 | case Expr::TypoExprClass: | |||
13562 | case Expr::DependentScopeDeclRefExprClass: | |||
13563 | case Expr::CXXConstructExprClass: | |||
13564 | case Expr::CXXInheritedCtorInitExprClass: | |||
13565 | case Expr::CXXStdInitializerListExprClass: | |||
13566 | case Expr::CXXBindTemporaryExprClass: | |||
13567 | case Expr::ExprWithCleanupsClass: | |||
13568 | case Expr::CXXTemporaryObjectExprClass: | |||
13569 | case Expr::CXXUnresolvedConstructExprClass: | |||
13570 | case Expr::CXXDependentScopeMemberExprClass: | |||
13571 | case Expr::UnresolvedMemberExprClass: | |||
13572 | case Expr::ObjCStringLiteralClass: | |||
13573 | case Expr::ObjCBoxedExprClass: | |||
13574 | case Expr::ObjCArrayLiteralClass: | |||
13575 | case Expr::ObjCDictionaryLiteralClass: | |||
13576 | case Expr::ObjCEncodeExprClass: | |||
13577 | case Expr::ObjCMessageExprClass: | |||
13578 | case Expr::ObjCSelectorExprClass: | |||
13579 | case Expr::ObjCProtocolExprClass: | |||
13580 | case Expr::ObjCIvarRefExprClass: | |||
13581 | case Expr::ObjCPropertyRefExprClass: | |||
13582 | case Expr::ObjCSubscriptRefExprClass: | |||
13583 | case Expr::ObjCIsaExprClass: | |||
13584 | case Expr::ObjCAvailabilityCheckExprClass: | |||
13585 | case Expr::ShuffleVectorExprClass: | |||
13586 | case Expr::ConvertVectorExprClass: | |||
13587 | case Expr::BlockExprClass: | |||
13588 | case Expr::NoStmtClass: | |||
13589 | case Expr::OpaqueValueExprClass: | |||
13590 | case Expr::PackExpansionExprClass: | |||
13591 | case Expr::SubstNonTypeTemplateParmPackExprClass: | |||
13592 | case Expr::FunctionParmPackExprClass: | |||
13593 | case Expr::AsTypeExprClass: | |||
13594 | case Expr::ObjCIndirectCopyRestoreExprClass: | |||
13595 | case Expr::MaterializeTemporaryExprClass: | |||
13596 | case Expr::PseudoObjectExprClass: | |||
13597 | case Expr::AtomicExprClass: | |||
13598 | case Expr::LambdaExprClass: | |||
13599 | case Expr::CXXFoldExprClass: | |||
13600 | case Expr::CoawaitExprClass: | |||
13601 | case Expr::DependentCoawaitExprClass: | |||
13602 | case Expr::CoyieldExprClass: | |||
13603 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13604 | ||||
13605 | case Expr::InitListExprClass: { | |||
13606 | // C++03 [dcl.init]p13: If T is a scalar type, then a declaration of the | |||
13607 | // form "T x = { a };" is equivalent to "T x = a;". | |||
13608 | // Unless we're initializing a reference, T is a scalar as it is known to be | |||
13609 | // of integral or enumeration type. | |||
13610 | if (E->isRValue()) | |||
13611 | if (cast<InitListExpr>(E)->getNumInits() == 1) | |||
13612 | return CheckICE(cast<InitListExpr>(E)->getInit(0), Ctx); | |||
13613 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13614 | } | |||
13615 | ||||
13616 | case Expr::SizeOfPackExprClass: | |||
13617 | case Expr::GNUNullExprClass: | |||
13618 | case Expr::SourceLocExprClass: | |||
13619 | return NoDiag(); | |||
13620 | ||||
13621 | case Expr::SubstNonTypeTemplateParmExprClass: | |||
13622 | return | |||
13623 | CheckICE(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement(), Ctx); | |||
13624 | ||||
13625 | case Expr::ConstantExprClass: | |||
13626 | return CheckICE(cast<ConstantExpr>(E)->getSubExpr(), Ctx); | |||
13627 | ||||
13628 | case Expr::ParenExprClass: | |||
13629 | return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx); | |||
13630 | case Expr::GenericSelectionExprClass: | |||
13631 | return CheckICE(cast<GenericSelectionExpr>(E)->getResultExpr(), Ctx); | |||
13632 | case Expr::IntegerLiteralClass: | |||
13633 | case Expr::FixedPointLiteralClass: | |||
13634 | case Expr::CharacterLiteralClass: | |||
13635 | case Expr::ObjCBoolLiteralExprClass: | |||
13636 | case Expr::CXXBoolLiteralExprClass: | |||
13637 | case Expr::CXXScalarValueInitExprClass: | |||
13638 | case Expr::TypeTraitExprClass: | |||
13639 | case Expr::ArrayTypeTraitExprClass: | |||
13640 | case Expr::ExpressionTraitExprClass: | |||
13641 | case Expr::CXXNoexceptExprClass: | |||
13642 | return NoDiag(); | |||
13643 | case Expr::CallExprClass: | |||
13644 | case Expr::CXXOperatorCallExprClass: { | |||
13645 | // C99 6.6/3 allows function calls within unevaluated subexpressions of | |||
13646 | // constant expressions, but they can never be ICEs because an ICE cannot | |||
13647 | // contain an operand of (pointer to) function type. | |||
13648 | const CallExpr *CE = cast<CallExpr>(E); | |||
13649 | if (CE->getBuiltinCallee()) | |||
13650 | return CheckEvalInICE(E, Ctx); | |||
13651 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13652 | } | |||
13653 | case Expr::DeclRefExprClass: { | |||
13654 | if (isa<EnumConstantDecl>(cast<DeclRefExpr>(E)->getDecl())) | |||
13655 | return NoDiag(); | |||
13656 | const ValueDecl *D = cast<DeclRefExpr>(E)->getDecl(); | |||
13657 | if (Ctx.getLangOpts().CPlusPlus && | |||
13658 | D && IsConstNonVolatile(D->getType())) { | |||
13659 | // Parameter variables are never constants. Without this check, | |||
13660 | // getAnyInitializer() can find a default argument, which leads | |||
13661 | // to chaos. | |||
13662 | if (isa<ParmVarDecl>(D)) | |||
13663 | return ICEDiag(IK_NotICE, cast<DeclRefExpr>(E)->getLocation()); | |||
13664 | ||||
13665 | // C++ 7.1.5.1p2 | |||
13666 | // A variable of non-volatile const-qualified integral or enumeration | |||
13667 | // type initialized by an ICE can be used in ICEs. | |||
13668 | if (const VarDecl *Dcl = dyn_cast<VarDecl>(D)) { | |||
13669 | if (!Dcl->getType()->isIntegralOrEnumerationType()) | |||
13670 | return ICEDiag(IK_NotICE, cast<DeclRefExpr>(E)->getLocation()); | |||
13671 | ||||
13672 | const VarDecl *VD; | |||
13673 | // Look for a declaration of this variable that has an initializer, and | |||
13674 | // check whether it is an ICE. | |||
13675 | if (Dcl->getAnyInitializer(VD) && VD->checkInitIsICE()) | |||
13676 | return NoDiag(); | |||
13677 | else | |||
13678 | return ICEDiag(IK_NotICE, cast<DeclRefExpr>(E)->getLocation()); | |||
13679 | } | |||
13680 | } | |||
13681 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13682 | } | |||
13683 | case Expr::UnaryOperatorClass: { | |||
13684 | const UnaryOperator *Exp = cast<UnaryOperator>(E); | |||
13685 | switch (Exp->getOpcode()) { | |||
13686 | case UO_PostInc: | |||
13687 | case UO_PostDec: | |||
13688 | case UO_PreInc: | |||
13689 | case UO_PreDec: | |||
13690 | case UO_AddrOf: | |||
13691 | case UO_Deref: | |||
13692 | case UO_Coawait: | |||
13693 | // C99 6.6/3 allows increment and decrement within unevaluated | |||
13694 | // subexpressions of constant expressions, but they can never be ICEs | |||
13695 | // because an ICE cannot contain an lvalue operand. | |||
13696 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13697 | case UO_Extension: | |||
13698 | case UO_LNot: | |||
13699 | case UO_Plus: | |||
13700 | case UO_Minus: | |||
13701 | case UO_Not: | |||
13702 | case UO_Real: | |||
13703 | case UO_Imag: | |||
13704 | return CheckICE(Exp->getSubExpr(), Ctx); | |||
13705 | } | |||
13706 | llvm_unreachable("invalid unary operator class")::llvm::llvm_unreachable_internal("invalid unary operator class" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13706); | |||
13707 | } | |||
13708 | case Expr::OffsetOfExprClass: { | |||
13709 | // Note that per C99, offsetof must be an ICE. And AFAIK, using | |||
13710 | // EvaluateAsRValue matches the proposed gcc behavior for cases like | |||
13711 | // "offsetof(struct s{int x[4];}, x[1.0])". This doesn't affect | |||
13712 | // compliance: we should warn earlier for offsetof expressions with | |||
13713 | // array subscripts that aren't ICEs, and if the array subscripts | |||
13714 | // are ICEs, the value of the offsetof must be an integer constant. | |||
13715 | return CheckEvalInICE(E, Ctx); | |||
13716 | } | |||
13717 | case Expr::UnaryExprOrTypeTraitExprClass: { | |||
13718 | const UnaryExprOrTypeTraitExpr *Exp = cast<UnaryExprOrTypeTraitExpr>(E); | |||
13719 | if ((Exp->getKind() == UETT_SizeOf) && | |||
13720 | Exp->getTypeOfArgument()->isVariableArrayType()) | |||
13721 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13722 | return NoDiag(); | |||
13723 | } | |||
13724 | case Expr::BinaryOperatorClass: { | |||
13725 | const BinaryOperator *Exp = cast<BinaryOperator>(E); | |||
13726 | switch (Exp->getOpcode()) { | |||
13727 | case BO_PtrMemD: | |||
13728 | case BO_PtrMemI: | |||
13729 | case BO_Assign: | |||
13730 | case BO_MulAssign: | |||
13731 | case BO_DivAssign: | |||
13732 | case BO_RemAssign: | |||
13733 | case BO_AddAssign: | |||
13734 | case BO_SubAssign: | |||
13735 | case BO_ShlAssign: | |||
13736 | case BO_ShrAssign: | |||
13737 | case BO_AndAssign: | |||
13738 | case BO_XorAssign: | |||
13739 | case BO_OrAssign: | |||
13740 | // C99 6.6/3 allows assignments within unevaluated subexpressions of | |||
13741 | // constant expressions, but they can never be ICEs because an ICE cannot | |||
13742 | // contain an lvalue operand. | |||
13743 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13744 | ||||
13745 | case BO_Mul: | |||
13746 | case BO_Div: | |||
13747 | case BO_Rem: | |||
13748 | case BO_Add: | |||
13749 | case BO_Sub: | |||
13750 | case BO_Shl: | |||
13751 | case BO_Shr: | |||
13752 | case BO_LT: | |||
13753 | case BO_GT: | |||
13754 | case BO_LE: | |||
13755 | case BO_GE: | |||
13756 | case BO_EQ: | |||
13757 | case BO_NE: | |||
13758 | case BO_And: | |||
13759 | case BO_Xor: | |||
13760 | case BO_Or: | |||
13761 | case BO_Comma: | |||
13762 | case BO_Cmp: { | |||
13763 | ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); | |||
13764 | ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); | |||
13765 | if (Exp->getOpcode() == BO_Div || | |||
13766 | Exp->getOpcode() == BO_Rem) { | |||
13767 | // EvaluateAsRValue gives an error for undefined Div/Rem, so make sure | |||
13768 | // we don't evaluate one. | |||
13769 | if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICE) { | |||
13770 | llvm::APSInt REval = Exp->getRHS()->EvaluateKnownConstInt(Ctx); | |||
13771 | if (REval == 0) | |||
13772 | return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc()); | |||
13773 | if (REval.isSigned() && REval.isAllOnesValue()) { | |||
13774 | llvm::APSInt LEval = Exp->getLHS()->EvaluateKnownConstInt(Ctx); | |||
13775 | if (LEval.isMinSignedValue()) | |||
13776 | return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc()); | |||
13777 | } | |||
13778 | } | |||
13779 | } | |||
13780 | if (Exp->getOpcode() == BO_Comma) { | |||
13781 | if (Ctx.getLangOpts().C99) { | |||
13782 | // C99 6.6p3 introduces a strange edge case: comma can be in an ICE | |||
13783 | // if it isn't evaluated. | |||
13784 | if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICE) | |||
13785 | return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc()); | |||
13786 | } else { | |||
13787 | // In both C89 and C++, commas in ICEs are illegal. | |||
13788 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13789 | } | |||
13790 | } | |||
13791 | return Worst(LHSResult, RHSResult); | |||
13792 | } | |||
13793 | case BO_LAnd: | |||
13794 | case BO_LOr: { | |||
13795 | ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); | |||
13796 | ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); | |||
13797 | if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICEIfUnevaluated) { | |||
13798 | // Rare case where the RHS has a comma "side-effect"; we need | |||
13799 | // to actually check the condition to see whether the side | |||
13800 | // with the comma is evaluated. | |||
13801 | if ((Exp->getOpcode() == BO_LAnd) != | |||
13802 | (Exp->getLHS()->EvaluateKnownConstInt(Ctx) == 0)) | |||
13803 | return RHSResult; | |||
13804 | return NoDiag(); | |||
13805 | } | |||
13806 | ||||
13807 | return Worst(LHSResult, RHSResult); | |||
13808 | } | |||
13809 | } | |||
13810 | llvm_unreachable("invalid binary operator kind")::llvm::llvm_unreachable_internal("invalid binary operator kind" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13810); | |||
13811 | } | |||
13812 | case Expr::ImplicitCastExprClass: | |||
13813 | case Expr::CStyleCastExprClass: | |||
13814 | case Expr::CXXFunctionalCastExprClass: | |||
13815 | case Expr::CXXStaticCastExprClass: | |||
13816 | case Expr::CXXReinterpretCastExprClass: | |||
13817 | case Expr::CXXConstCastExprClass: | |||
13818 | case Expr::ObjCBridgedCastExprClass: { | |||
13819 | const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr(); | |||
13820 | if (isa<ExplicitCastExpr>(E)) { | |||
13821 | if (const FloatingLiteral *FL | |||
13822 | = dyn_cast<FloatingLiteral>(SubExpr->IgnoreParenImpCasts())) { | |||
13823 | unsigned DestWidth = Ctx.getIntWidth(E->getType()); | |||
13824 | bool DestSigned = E->getType()->isSignedIntegerOrEnumerationType(); | |||
13825 | APSInt IgnoredVal(DestWidth, !DestSigned); | |||
13826 | bool Ignored; | |||
13827 | // If the value does not fit in the destination type, the behavior is | |||
13828 | // undefined, so we are not required to treat it as a constant | |||
13829 | // expression. | |||
13830 | if (FL->getValue().convertToInteger(IgnoredVal, | |||
13831 | llvm::APFloat::rmTowardZero, | |||
13832 | &Ignored) & APFloat::opInvalidOp) | |||
13833 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13834 | return NoDiag(); | |||
13835 | } | |||
13836 | } | |||
13837 | switch (cast<CastExpr>(E)->getCastKind()) { | |||
13838 | case CK_LValueToRValue: | |||
13839 | case CK_AtomicToNonAtomic: | |||
13840 | case CK_NonAtomicToAtomic: | |||
13841 | case CK_NoOp: | |||
13842 | case CK_IntegralToBoolean: | |||
13843 | case CK_IntegralCast: | |||
13844 | return CheckICE(SubExpr, Ctx); | |||
13845 | default: | |||
13846 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13847 | } | |||
13848 | } | |||
13849 | case Expr::BinaryConditionalOperatorClass: { | |||
13850 | const BinaryConditionalOperator *Exp = cast<BinaryConditionalOperator>(E); | |||
13851 | ICEDiag CommonResult = CheckICE(Exp->getCommon(), Ctx); | |||
13852 | if (CommonResult.Kind == IK_NotICE) return CommonResult; | |||
13853 | ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx); | |||
13854 | if (FalseResult.Kind == IK_NotICE) return FalseResult; | |||
13855 | if (CommonResult.Kind == IK_ICEIfUnevaluated) return CommonResult; | |||
13856 | if (FalseResult.Kind == IK_ICEIfUnevaluated && | |||
13857 | Exp->getCommon()->EvaluateKnownConstInt(Ctx) != 0) return NoDiag(); | |||
13858 | return FalseResult; | |||
13859 | } | |||
13860 | case Expr::ConditionalOperatorClass: { | |||
13861 | const ConditionalOperator *Exp = cast<ConditionalOperator>(E); | |||
13862 | // If the condition (ignoring parens) is a __builtin_constant_p call, | |||
13863 | // then only the true side is actually considered in an integer constant | |||
13864 | // expression, and it is fully evaluated. This is an important GNU | |||
13865 | // extension. See GCC PR38377 for discussion. | |||
13866 | if (const CallExpr *CallCE | |||
13867 | = dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts())) | |||
13868 | if (CallCE->getBuiltinCallee() == Builtin::BI__builtin_constant_p) | |||
13869 | return CheckEvalInICE(E, Ctx); | |||
13870 | ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx); | |||
13871 | if (CondResult.Kind == IK_NotICE) | |||
13872 | return CondResult; | |||
13873 | ||||
13874 | ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx); | |||
13875 | ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx); | |||
13876 | ||||
13877 | if (TrueResult.Kind == IK_NotICE) | |||
13878 | return TrueResult; | |||
13879 | if (FalseResult.Kind == IK_NotICE) | |||
13880 | return FalseResult; | |||
13881 | if (CondResult.Kind == IK_ICEIfUnevaluated) | |||
13882 | return CondResult; | |||
13883 | if (TrueResult.Kind == IK_ICE && FalseResult.Kind == IK_ICE) | |||
13884 | return NoDiag(); | |||
13885 | // Rare case where the diagnostics depend on which side is evaluated | |||
13886 | // Note that if we get here, CondResult is 0, and at least one of | |||
13887 | // TrueResult and FalseResult is non-zero. | |||
13888 | if (Exp->getCond()->EvaluateKnownConstInt(Ctx) == 0) | |||
13889 | return FalseResult; | |||
13890 | return TrueResult; | |||
13891 | } | |||
13892 | case Expr::CXXDefaultArgExprClass: | |||
13893 | return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx); | |||
13894 | case Expr::CXXDefaultInitExprClass: | |||
13895 | return CheckICE(cast<CXXDefaultInitExpr>(E)->getExpr(), Ctx); | |||
13896 | case Expr::ChooseExprClass: { | |||
13897 | return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(), Ctx); | |||
13898 | } | |||
13899 | case Expr::BuiltinBitCastExprClass: { | |||
13900 | if (!checkBitCastConstexprEligibility(nullptr, Ctx, cast<CastExpr>(E))) | |||
13901 | return ICEDiag(IK_NotICE, E->getBeginLoc()); | |||
13902 | return CheckICE(cast<CastExpr>(E)->getSubExpr(), Ctx); | |||
13903 | } | |||
13904 | } | |||
13905 | ||||
13906 | llvm_unreachable("Invalid StmtClass!")::llvm::llvm_unreachable_internal("Invalid StmtClass!", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13906); | |||
13907 | } | |||
13908 | ||||
13909 | /// Evaluate an expression as a C++11 integral constant expression. | |||
13910 | static bool EvaluateCPlusPlus11IntegralConstantExpr(const ASTContext &Ctx, | |||
13911 | const Expr *E, | |||
13912 | llvm::APSInt *Value, | |||
13913 | SourceLocation *Loc) { | |||
13914 | if (!E->getType()->isIntegralOrUnscopedEnumerationType()) { | |||
13915 | if (Loc) *Loc = E->getExprLoc(); | |||
13916 | return false; | |||
13917 | } | |||
13918 | ||||
13919 | APValue Result; | |||
13920 | if (!E->isCXX11ConstantExpr(Ctx, &Result, Loc)) | |||
13921 | return false; | |||
13922 | ||||
13923 | if (!Result.isInt()) { | |||
13924 | if (Loc) *Loc = E->getExprLoc(); | |||
13925 | return false; | |||
13926 | } | |||
13927 | ||||
13928 | if (Value) *Value = Result.getInt(); | |||
13929 | return true; | |||
13930 | } | |||
13931 | ||||
13932 | bool Expr::isIntegerConstantExpr(const ASTContext &Ctx, | |||
13933 | SourceLocation *Loc) const { | |||
13934 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13935, __PRETTY_FUNCTION__)) | |||
13935 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13935, __PRETTY_FUNCTION__)); | |||
13936 | ||||
13937 | if (Ctx.getLangOpts().CPlusPlus11) | |||
13938 | return EvaluateCPlusPlus11IntegralConstantExpr(Ctx, this, nullptr, Loc); | |||
13939 | ||||
13940 | ICEDiag D = CheckICE(this, Ctx); | |||
13941 | if (D.Kind != IK_ICE) { | |||
13942 | if (Loc) *Loc = D.Loc; | |||
13943 | return false; | |||
13944 | } | |||
13945 | return true; | |||
13946 | } | |||
13947 | ||||
13948 | bool Expr::isIntegerConstantExpr(llvm::APSInt &Value, const ASTContext &Ctx, | |||
13949 | SourceLocation *Loc, bool isEvaluated) const { | |||
13950 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13951, __PRETTY_FUNCTION__)) | |||
13951 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13951, __PRETTY_FUNCTION__)); | |||
13952 | ||||
13953 | if (Ctx.getLangOpts().CPlusPlus11) | |||
13954 | return EvaluateCPlusPlus11IntegralConstantExpr(Ctx, this, &Value, Loc); | |||
13955 | ||||
13956 | if (!isIntegerConstantExpr(Ctx, Loc)) | |||
13957 | return false; | |||
13958 | ||||
13959 | // The only possible side-effects here are due to UB discovered in the | |||
13960 | // evaluation (for instance, INT_MAX + 1). In such a case, we are still | |||
13961 | // required to treat the expression as an ICE, so we produce the folded | |||
13962 | // value. | |||
13963 | EvalResult ExprResult; | |||
13964 | Expr::EvalStatus Status; | |||
13965 | EvalInfo Info(Ctx, Status, EvalInfo::EM_IgnoreSideEffects); | |||
13966 | Info.InConstantContext = true; | |||
13967 | ||||
13968 | if (!::EvaluateAsInt(this, ExprResult, Ctx, SE_AllowSideEffects, Info)) | |||
13969 | llvm_unreachable("ICE cannot be evaluated!")::llvm::llvm_unreachable_internal("ICE cannot be evaluated!", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13969); | |||
13970 | ||||
13971 | Value = ExprResult.Val.getInt(); | |||
13972 | return true; | |||
13973 | } | |||
13974 | ||||
13975 | bool Expr::isCXX98IntegralConstantExpr(const ASTContext &Ctx) const { | |||
13976 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13977, __PRETTY_FUNCTION__)) | |||
13977 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13977, __PRETTY_FUNCTION__)); | |||
13978 | ||||
13979 | return CheckICE(this, Ctx).Kind == IK_ICE; | |||
13980 | } | |||
13981 | ||||
13982 | bool Expr::isCXX11ConstantExpr(const ASTContext &Ctx, APValue *Result, | |||
13983 | SourceLocation *Loc) const { | |||
13984 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13985, __PRETTY_FUNCTION__)) | |||
13985 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13985, __PRETTY_FUNCTION__)); | |||
13986 | ||||
13987 | // We support this checking in C++98 mode in order to diagnose compatibility | |||
13988 | // issues. | |||
13989 | assert(Ctx.getLangOpts().CPlusPlus)((Ctx.getLangOpts().CPlusPlus) ? static_cast<void> (0) : __assert_fail ("Ctx.getLangOpts().CPlusPlus", "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 13989, __PRETTY_FUNCTION__)); | |||
13990 | ||||
13991 | // Build evaluation settings. | |||
13992 | Expr::EvalStatus Status; | |||
13993 | SmallVector<PartialDiagnosticAt, 8> Diags; | |||
13994 | Status.Diag = &Diags; | |||
13995 | EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpression); | |||
13996 | ||||
13997 | APValue Scratch; | |||
13998 | bool IsConstExpr = | |||
13999 | ::EvaluateAsRValue(Info, this, Result ? *Result : Scratch) && | |||
14000 | // FIXME: We don't produce a diagnostic for this, but the callers that | |||
14001 | // call us on arbitrary full-expressions should generally not care. | |||
14002 | Info.discardCleanups() && !Status.HasSideEffects; | |||
14003 | ||||
14004 | if (!Diags.empty()) { | |||
14005 | IsConstExpr = false; | |||
14006 | if (Loc) *Loc = Diags[0].first; | |||
14007 | } else if (!IsConstExpr) { | |||
14008 | // FIXME: This shouldn't happen. | |||
14009 | if (Loc) *Loc = getExprLoc(); | |||
14010 | } | |||
14011 | ||||
14012 | return IsConstExpr; | |||
14013 | } | |||
14014 | ||||
14015 | bool Expr::EvaluateWithSubstitution(APValue &Value, ASTContext &Ctx, | |||
14016 | const FunctionDecl *Callee, | |||
14017 | ArrayRef<const Expr*> Args, | |||
14018 | const Expr *This) const { | |||
14019 | assert(!isValueDependent() &&((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 14020, __PRETTY_FUNCTION__)) | |||
14020 | "Expression evaluator can't be called on a dependent expression.")((!isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 14020, __PRETTY_FUNCTION__)); | |||
14021 | ||||
14022 | Expr::EvalStatus Status; | |||
14023 | EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpressionUnevaluated); | |||
14024 | Info.InConstantContext = true; | |||
14025 | ||||
14026 | LValue ThisVal; | |||
14027 | const LValue *ThisPtr = nullptr; | |||
14028 | if (This) { | |||
14029 | #ifndef NDEBUG | |||
14030 | auto *MD = dyn_cast<CXXMethodDecl>(Callee); | |||
14031 | assert(MD && "Don't provide `this` for non-methods.")((MD && "Don't provide `this` for non-methods.") ? static_cast <void> (0) : __assert_fail ("MD && \"Don't provide `this` for non-methods.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 14031, __PRETTY_FUNCTION__)); | |||
14032 | assert(!MD->isStatic() && "Don't provide `this` for static methods.")((!MD->isStatic() && "Don't provide `this` for static methods." ) ? static_cast<void> (0) : __assert_fail ("!MD->isStatic() && \"Don't provide `this` for static methods.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 14032, __PRETTY_FUNCTION__)); | |||
14033 | #endif | |||
14034 | if (EvaluateObjectArgument(Info, This, ThisVal)) | |||
14035 | ThisPtr = &ThisVal; | |||
14036 | if (Info.EvalStatus.HasSideEffects) | |||
14037 | return false; | |||
14038 | } | |||
14039 | ||||
14040 | ArgVector ArgValues(Args.size()); | |||
14041 | for (ArrayRef<const Expr*>::iterator I = Args.begin(), E = Args.end(); | |||
14042 | I != E; ++I) { | |||
14043 | if ((*I)->isValueDependent() || | |||
14044 | !Evaluate(ArgValues[I - Args.begin()], Info, *I)) | |||
14045 | // If evaluation fails, throw away the argument entirely. | |||
14046 | ArgValues[I - Args.begin()] = APValue(); | |||
14047 | if (Info.EvalStatus.HasSideEffects) | |||
14048 | return false; | |||
14049 | } | |||
14050 | ||||
14051 | // Build fake call to Callee. | |||
14052 | CallStackFrame Frame(Info, Callee->getLocation(), Callee, ThisPtr, | |||
14053 | ArgValues.data()); | |||
14054 | return Evaluate(Value, Info, this) && Info.discardCleanups() && | |||
14055 | !Info.EvalStatus.HasSideEffects; | |||
14056 | } | |||
14057 | ||||
14058 | bool Expr::isPotentialConstantExpr(const FunctionDecl *FD, | |||
14059 | SmallVectorImpl< | |||
14060 | PartialDiagnosticAt> &Diags) { | |||
14061 | // FIXME: It would be useful to check constexpr function templates, but at the | |||
14062 | // moment the constant expression evaluator cannot cope with the non-rigorous | |||
14063 | // ASTs which we build for dependent expressions. | |||
14064 | if (FD->isDependentContext()) | |||
14065 | return true; | |||
14066 | ||||
14067 | Expr::EvalStatus Status; | |||
14068 | Status.Diag = &Diags; | |||
14069 | ||||
14070 | EvalInfo Info(FD->getASTContext(), Status, EvalInfo::EM_ConstantExpression); | |||
14071 | Info.InConstantContext = true; | |||
14072 | Info.CheckingPotentialConstantExpression = true; | |||
14073 | ||||
14074 | // The constexpr VM attempts to compile all methods to bytecode here. | |||
14075 | if (Info.EnableNewConstInterp) { | |||
14076 | auto &InterpCtx = Info.Ctx.getInterpContext(); | |||
14077 | switch (InterpCtx.isPotentialConstantExpr(Info, FD)) { | |||
14078 | case interp::InterpResult::Success: | |||
14079 | case interp::InterpResult::Fail: | |||
14080 | return Diags.empty(); | |||
14081 | case interp::InterpResult::Bail: | |||
14082 | break; | |||
14083 | } | |||
14084 | } | |||
14085 | ||||
14086 | const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD); | |||
14087 | const CXXRecordDecl *RD = MD ? MD->getParent()->getCanonicalDecl() : nullptr; | |||
14088 | ||||
14089 | // Fabricate an arbitrary expression on the stack and pretend that it | |||
14090 | // is a temporary being used as the 'this' pointer. | |||
14091 | LValue This; | |||
14092 | ImplicitValueInitExpr VIE(RD ? Info.Ctx.getRecordType(RD) : Info.Ctx.IntTy); | |||
14093 | This.set({&VIE, Info.CurrentCall->Index}); | |||
14094 | ||||
14095 | ArrayRef<const Expr*> Args; | |||
14096 | ||||
14097 | APValue Scratch; | |||
14098 | if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) { | |||
14099 | // Evaluate the call as a constant initializer, to allow the construction | |||
14100 | // of objects of non-literal types. | |||
14101 | Info.setEvaluatingDecl(This.getLValueBase(), Scratch); | |||
14102 | HandleConstructorCall(&VIE, This, Args, CD, Info, Scratch); | |||
14103 | } else { | |||
14104 | SourceLocation Loc = FD->getLocation(); | |||
14105 | HandleFunctionCall(Loc, FD, (MD && MD->isInstance()) ? &This : nullptr, | |||
14106 | Args, FD->getBody(), Info, Scratch, nullptr); | |||
14107 | } | |||
14108 | ||||
14109 | return Diags.empty(); | |||
14110 | } | |||
14111 | ||||
14112 | bool Expr::isPotentialConstantExprUnevaluated(Expr *E, | |||
14113 | const FunctionDecl *FD, | |||
14114 | SmallVectorImpl< | |||
14115 | PartialDiagnosticAt> &Diags) { | |||
14116 | assert(!E->isValueDependent() &&((!E->isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!E->isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 14117, __PRETTY_FUNCTION__)) | |||
14117 | "Expression evaluator can't be called on a dependent expression.")((!E->isValueDependent() && "Expression evaluator can't be called on a dependent expression." ) ? static_cast<void> (0) : __assert_fail ("!E->isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 14117, __PRETTY_FUNCTION__)); | |||
14118 | ||||
14119 | Expr::EvalStatus Status; | |||
14120 | Status.Diag = &Diags; | |||
14121 | ||||
14122 | EvalInfo Info(FD->getASTContext(), Status, | |||
14123 | EvalInfo::EM_ConstantExpressionUnevaluated); | |||
14124 | Info.InConstantContext = true; | |||
14125 | Info.CheckingPotentialConstantExpression = true; | |||
14126 | ||||
14127 | // Fabricate a call stack frame to give the arguments a plausible cover story. | |||
14128 | ArrayRef<const Expr*> Args; | |||
14129 | ArgVector ArgValues(0); | |||
14130 | bool Success = EvaluateArgs(Args, ArgValues, Info, FD); | |||
14131 | (void)Success; | |||
14132 | assert(Success &&((Success && "Failed to set up arguments for potential constant evaluation" ) ? static_cast<void> (0) : __assert_fail ("Success && \"Failed to set up arguments for potential constant evaluation\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 14133, __PRETTY_FUNCTION__)) | |||
14133 | "Failed to set up arguments for potential constant evaluation")((Success && "Failed to set up arguments for potential constant evaluation" ) ? static_cast<void> (0) : __assert_fail ("Success && \"Failed to set up arguments for potential constant evaluation\"" , "/build/llvm-toolchain-snapshot-10~svn373517/tools/clang/lib/AST/ExprConstant.cpp" , 14133, __PRETTY_FUNCTION__)); | |||
14134 | CallStackFrame Frame(Info, SourceLocation(), FD, nullptr, ArgValues.data()); | |||
14135 | ||||
14136 | APValue ResultScratch; | |||
14137 | Evaluate(ResultScratch, Info, E); | |||
14138 | return Diags.empty(); | |||
14139 | } | |||
14140 | ||||
14141 | bool Expr::tryEvaluateObjectSize(uint64_t &Result, ASTContext &Ctx, | |||
14142 | unsigned Type) const { | |||
14143 | if (!getType()->isPointerType()) | |||
14144 | return false; | |||
14145 | ||||
14146 | Expr::EvalStatus Status; | |||
14147 | EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantFold); | |||
14148 | return tryEvaluateBuiltinObjectSize(this, Type, Info, Result); | |||
14149 | } |