Bug Summary

File:clang/lib/AST/ExprConstant.cpp
Warning:line 3179, column 27
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name ExprConstant.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/build-llvm -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D CLANG_ROUND_TRIP_CC1_ARGS=ON -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I tools/clang/lib/AST -I /build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST -I /build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/include -I tools/clang/include -I include -I /build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/llvm/include -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-14/lib/clang/14.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-command-line-argument -Wno-unknown-warning-option -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/build-llvm -ferror-limit 19 -fvisibility-inlines-hidden -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2021-11-10-160236-22541-1 -x c++ /build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp
1//===--- ExprConstant.cpp - Expression Constant Evaluator -----------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements the Expr constant evaluator.
10//
11// Constant expression evaluation produces four main results:
12//
13// * A success/failure flag indicating whether constant folding was successful.
14// This is the 'bool' return value used by most of the code in this file. A
15// 'false' return value indicates that constant folding has failed, and any
16// appropriate diagnostic has already been produced.
17//
18// * An evaluated result, valid only if constant folding has not failed.
19//
20// * A flag indicating if evaluation encountered (unevaluated) side-effects.
21// These arise in cases such as (sideEffect(), 0) and (sideEffect() || 1),
22// where it is possible to determine the evaluated result regardless.
23//
24// * A set of notes indicating why the evaluation was not a constant expression
25// (under the C++11 / C++1y rules only, at the moment), or, if folding failed
26// too, why the expression could not be folded.
27//
28// If we are checking for a potential constant expression, failure to constant
29// fold a potential constant sub-expression will be indicated by a 'false'
30// return value (the expression could not be folded) and no diagnostic (the
31// expression is not necessarily non-constant).
32//
33//===----------------------------------------------------------------------===//
34
35#include "Interp/Context.h"
36#include "Interp/Frame.h"
37#include "Interp/State.h"
38#include "clang/AST/APValue.h"
39#include "clang/AST/ASTContext.h"
40#include "clang/AST/ASTDiagnostic.h"
41#include "clang/AST/ASTLambda.h"
42#include "clang/AST/Attr.h"
43#include "clang/AST/CXXInheritance.h"
44#include "clang/AST/CharUnits.h"
45#include "clang/AST/CurrentSourceLocExprScope.h"
46#include "clang/AST/Expr.h"
47#include "clang/AST/OSLog.h"
48#include "clang/AST/OptionalDiagnostic.h"
49#include "clang/AST/RecordLayout.h"
50#include "clang/AST/StmtVisitor.h"
51#include "clang/AST/TypeLoc.h"
52#include "clang/Basic/Builtins.h"
53#include "clang/Basic/TargetInfo.h"
54#include "llvm/ADT/APFixedPoint.h"
55#include "llvm/ADT/Optional.h"
56#include "llvm/ADT/SmallBitVector.h"
57#include "llvm/Support/Debug.h"
58#include "llvm/Support/SaveAndRestore.h"
59#include "llvm/Support/raw_ostream.h"
60#include <cstring>
61#include <functional>
62
63#define DEBUG_TYPE"exprconstant" "exprconstant"
64
65using namespace clang;
66using llvm::APFixedPoint;
67using llvm::APInt;
68using llvm::APSInt;
69using llvm::APFloat;
70using llvm::FixedPointSemantics;
71using llvm::Optional;
72
73namespace {
74 struct LValue;
75 class CallStackFrame;
76 class EvalInfo;
77
78 using SourceLocExprScopeGuard =
79 CurrentSourceLocExprScope::SourceLocExprScopeGuard;
80
81 static QualType getType(APValue::LValueBase B) {
82 return B.getType();
83 }
84
85 /// Get an LValue path entry, which is known to not be an array index, as a
86 /// field declaration.
87 static const FieldDecl *getAsField(APValue::LValuePathEntry E) {
88 return dyn_cast_or_null<FieldDecl>(E.getAsBaseOrMember().getPointer());
89 }
90 /// Get an LValue path entry, which is known to not be an array index, as a
91 /// base class declaration.
92 static const CXXRecordDecl *getAsBaseClass(APValue::LValuePathEntry E) {
93 return dyn_cast_or_null<CXXRecordDecl>(E.getAsBaseOrMember().getPointer());
94 }
95 /// Determine whether this LValue path entry for a base class names a virtual
96 /// base class.
97 static bool isVirtualBaseClass(APValue::LValuePathEntry E) {
98 return E.getAsBaseOrMember().getInt();
99 }
100
101 /// Given an expression, determine the type used to store the result of
102 /// evaluating that expression.
103 static QualType getStorageType(const ASTContext &Ctx, const Expr *E) {
104 if (E->isPRValue())
105 return E->getType();
106 return Ctx.getLValueReferenceType(E->getType());
107 }
108
109 /// Given a CallExpr, try to get the alloc_size attribute. May return null.
110 static const AllocSizeAttr *getAllocSizeAttr(const CallExpr *CE) {
111 if (const FunctionDecl *DirectCallee = CE->getDirectCallee())
112 return DirectCallee->getAttr<AllocSizeAttr>();
113 if (const Decl *IndirectCallee = CE->getCalleeDecl())
114 return IndirectCallee->getAttr<AllocSizeAttr>();
115 return nullptr;
116 }
117
118 /// Attempts to unwrap a CallExpr (with an alloc_size attribute) from an Expr.
119 /// This will look through a single cast.
120 ///
121 /// Returns null if we couldn't unwrap a function with alloc_size.
122 static const CallExpr *tryUnwrapAllocSizeCall(const Expr *E) {
123 if (!E->getType()->isPointerType())
124 return nullptr;
125
126 E = E->IgnoreParens();
127 // If we're doing a variable assignment from e.g. malloc(N), there will
128 // probably be a cast of some kind. In exotic cases, we might also see a
129 // top-level ExprWithCleanups. Ignore them either way.
130 if (const auto *FE = dyn_cast<FullExpr>(E))
131 E = FE->getSubExpr()->IgnoreParens();
132
133 if (const auto *Cast = dyn_cast<CastExpr>(E))
134 E = Cast->getSubExpr()->IgnoreParens();
135
136 if (const auto *CE = dyn_cast<CallExpr>(E))
137 return getAllocSizeAttr(CE) ? CE : nullptr;
138 return nullptr;
139 }
140
141 /// Determines whether or not the given Base contains a call to a function
142 /// with the alloc_size attribute.
143 static bool isBaseAnAllocSizeCall(APValue::LValueBase Base) {
144 const auto *E = Base.dyn_cast<const Expr *>();
145 return E && E->getType()->isPointerType() && tryUnwrapAllocSizeCall(E);
146 }
147
148 /// Determines whether the given kind of constant expression is only ever
149 /// used for name mangling. If so, it's permitted to reference things that we
150 /// can't generate code for (in particular, dllimported functions).
151 static bool isForManglingOnly(ConstantExprKind Kind) {
152 switch (Kind) {
153 case ConstantExprKind::Normal:
154 case ConstantExprKind::ClassTemplateArgument:
155 case ConstantExprKind::ImmediateInvocation:
156 // Note that non-type template arguments of class type are emitted as
157 // template parameter objects.
158 return false;
159
160 case ConstantExprKind::NonClassTemplateArgument:
161 return true;
162 }
163 llvm_unreachable("unknown ConstantExprKind")::llvm::llvm_unreachable_internal("unknown ConstantExprKind",
"/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 163)
;
164 }
165
166 static bool isTemplateArgument(ConstantExprKind Kind) {
167 switch (Kind) {
168 case ConstantExprKind::Normal:
169 case ConstantExprKind::ImmediateInvocation:
170 return false;
171
172 case ConstantExprKind::ClassTemplateArgument:
173 case ConstantExprKind::NonClassTemplateArgument:
174 return true;
175 }
176 llvm_unreachable("unknown ConstantExprKind")::llvm::llvm_unreachable_internal("unknown ConstantExprKind",
"/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 176)
;
177 }
178
179 /// The bound to claim that an array of unknown bound has.
180 /// The value in MostDerivedArraySize is undefined in this case. So, set it
181 /// to an arbitrary value that's likely to loudly break things if it's used.
182 static const uint64_t AssumedSizeForUnsizedArray =
183 std::numeric_limits<uint64_t>::max() / 2;
184
185 /// Determines if an LValue with the given LValueBase will have an unsized
186 /// array in its designator.
187 /// Find the path length and type of the most-derived subobject in the given
188 /// path, and find the size of the containing array, if any.
189 static unsigned
190 findMostDerivedSubobject(ASTContext &Ctx, APValue::LValueBase Base,
191 ArrayRef<APValue::LValuePathEntry> Path,
192 uint64_t &ArraySize, QualType &Type, bool &IsArray,
193 bool &FirstEntryIsUnsizedArray) {
194 // This only accepts LValueBases from APValues, and APValues don't support
195 // arrays that lack size info.
196 assert(!isBaseAnAllocSizeCall(Base) &&(static_cast <bool> (!isBaseAnAllocSizeCall(Base) &&
"Unsized arrays shouldn't appear here") ? void (0) : __assert_fail
("!isBaseAnAllocSizeCall(Base) && \"Unsized arrays shouldn't appear here\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 197, __extension__ __PRETTY_FUNCTION__))
197 "Unsized arrays shouldn't appear here")(static_cast <bool> (!isBaseAnAllocSizeCall(Base) &&
"Unsized arrays shouldn't appear here") ? void (0) : __assert_fail
("!isBaseAnAllocSizeCall(Base) && \"Unsized arrays shouldn't appear here\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 197, __extension__ __PRETTY_FUNCTION__))
;
198 unsigned MostDerivedLength = 0;
199 Type = getType(Base);
200
201 for (unsigned I = 0, N = Path.size(); I != N; ++I) {
202 if (Type->isArrayType()) {
203 const ArrayType *AT = Ctx.getAsArrayType(Type);
204 Type = AT->getElementType();
205 MostDerivedLength = I + 1;
206 IsArray = true;
207
208 if (auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
209 ArraySize = CAT->getSize().getZExtValue();
210 } else {
211 assert(I == 0 && "unexpected unsized array designator")(static_cast <bool> (I == 0 && "unexpected unsized array designator"
) ? void (0) : __assert_fail ("I == 0 && \"unexpected unsized array designator\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 211, __extension__ __PRETTY_FUNCTION__))
;
212 FirstEntryIsUnsizedArray = true;
213 ArraySize = AssumedSizeForUnsizedArray;
214 }
215 } else if (Type->isAnyComplexType()) {
216 const ComplexType *CT = Type->castAs<ComplexType>();
217 Type = CT->getElementType();
218 ArraySize = 2;
219 MostDerivedLength = I + 1;
220 IsArray = true;
221 } else if (const FieldDecl *FD = getAsField(Path[I])) {
222 Type = FD->getType();
223 ArraySize = 0;
224 MostDerivedLength = I + 1;
225 IsArray = false;
226 } else {
227 // Path[I] describes a base class.
228 ArraySize = 0;
229 IsArray = false;
230 }
231 }
232 return MostDerivedLength;
233 }
234
235 /// A path from a glvalue to a subobject of that glvalue.
236 struct SubobjectDesignator {
237 /// True if the subobject was named in a manner not supported by C++11. Such
238 /// lvalues can still be folded, but they are not core constant expressions
239 /// and we cannot perform lvalue-to-rvalue conversions on them.
240 unsigned Invalid : 1;
241
242 /// Is this a pointer one past the end of an object?
243 unsigned IsOnePastTheEnd : 1;
244
245 /// Indicator of whether the first entry is an unsized array.
246 unsigned FirstEntryIsAnUnsizedArray : 1;
247
248 /// Indicator of whether the most-derived object is an array element.
249 unsigned MostDerivedIsArrayElement : 1;
250
251 /// The length of the path to the most-derived object of which this is a
252 /// subobject.
253 unsigned MostDerivedPathLength : 28;
254
255 /// The size of the array of which the most-derived object is an element.
256 /// This will always be 0 if the most-derived object is not an array
257 /// element. 0 is not an indicator of whether or not the most-derived object
258 /// is an array, however, because 0-length arrays are allowed.
259 ///
260 /// If the current array is an unsized array, the value of this is
261 /// undefined.
262 uint64_t MostDerivedArraySize;
263
264 /// The type of the most derived object referred to by this address.
265 QualType MostDerivedType;
266
267 typedef APValue::LValuePathEntry PathEntry;
268
269 /// The entries on the path from the glvalue to the designated subobject.
270 SmallVector<PathEntry, 8> Entries;
271
272 SubobjectDesignator() : Invalid(true) {}
273
274 explicit SubobjectDesignator(QualType T)
275 : Invalid(false), IsOnePastTheEnd(false),
276 FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false),
277 MostDerivedPathLength(0), MostDerivedArraySize(0),
278 MostDerivedType(T) {}
279
280 SubobjectDesignator(ASTContext &Ctx, const APValue &V)
281 : Invalid(!V.isLValue() || !V.hasLValuePath()), IsOnePastTheEnd(false),
282 FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false),
283 MostDerivedPathLength(0), MostDerivedArraySize(0) {
284 assert(V.isLValue() && "Non-LValue used to make an LValue designator?")(static_cast <bool> (V.isLValue() && "Non-LValue used to make an LValue designator?"
) ? void (0) : __assert_fail ("V.isLValue() && \"Non-LValue used to make an LValue designator?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 284, __extension__ __PRETTY_FUNCTION__))
;
285 if (!Invalid) {
286 IsOnePastTheEnd = V.isLValueOnePastTheEnd();
287 ArrayRef<PathEntry> VEntries = V.getLValuePath();
288 Entries.insert(Entries.end(), VEntries.begin(), VEntries.end());
289 if (V.getLValueBase()) {
290 bool IsArray = false;
291 bool FirstIsUnsizedArray = false;
292 MostDerivedPathLength = findMostDerivedSubobject(
293 Ctx, V.getLValueBase(), V.getLValuePath(), MostDerivedArraySize,
294 MostDerivedType, IsArray, FirstIsUnsizedArray);
295 MostDerivedIsArrayElement = IsArray;
296 FirstEntryIsAnUnsizedArray = FirstIsUnsizedArray;
297 }
298 }
299 }
300
301 void truncate(ASTContext &Ctx, APValue::LValueBase Base,
302 unsigned NewLength) {
303 if (Invalid)
304 return;
305
306 assert(Base && "cannot truncate path for null pointer")(static_cast <bool> (Base && "cannot truncate path for null pointer"
) ? void (0) : __assert_fail ("Base && \"cannot truncate path for null pointer\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 306, __extension__ __PRETTY_FUNCTION__))
;
307 assert(NewLength <= Entries.size() && "not a truncation")(static_cast <bool> (NewLength <= Entries.size() &&
"not a truncation") ? void (0) : __assert_fail ("NewLength <= Entries.size() && \"not a truncation\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 307, __extension__ __PRETTY_FUNCTION__))
;
308
309 if (NewLength == Entries.size())
310 return;
311 Entries.resize(NewLength);
312
313 bool IsArray = false;
314 bool FirstIsUnsizedArray = false;
315 MostDerivedPathLength = findMostDerivedSubobject(
316 Ctx, Base, Entries, MostDerivedArraySize, MostDerivedType, IsArray,
317 FirstIsUnsizedArray);
318 MostDerivedIsArrayElement = IsArray;
319 FirstEntryIsAnUnsizedArray = FirstIsUnsizedArray;
320 }
321
322 void setInvalid() {
323 Invalid = true;
324 Entries.clear();
325 }
326
327 /// Determine whether the most derived subobject is an array without a
328 /// known bound.
329 bool isMostDerivedAnUnsizedArray() const {
330 assert(!Invalid && "Calling this makes no sense on invalid designators")(static_cast <bool> (!Invalid && "Calling this makes no sense on invalid designators"
) ? void (0) : __assert_fail ("!Invalid && \"Calling this makes no sense on invalid designators\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 330, __extension__ __PRETTY_FUNCTION__))
;
331 return Entries.size() == 1 && FirstEntryIsAnUnsizedArray;
332 }
333
334 /// Determine what the most derived array's size is. Results in an assertion
335 /// failure if the most derived array lacks a size.
336 uint64_t getMostDerivedArraySize() const {
337 assert(!isMostDerivedAnUnsizedArray() && "Unsized array has no size")(static_cast <bool> (!isMostDerivedAnUnsizedArray() &&
"Unsized array has no size") ? void (0) : __assert_fail ("!isMostDerivedAnUnsizedArray() && \"Unsized array has no size\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 337, __extension__ __PRETTY_FUNCTION__))
;
338 return MostDerivedArraySize;
339 }
340
341 /// Determine whether this is a one-past-the-end pointer.
342 bool isOnePastTheEnd() const {
343 assert(!Invalid)(static_cast <bool> (!Invalid) ? void (0) : __assert_fail
("!Invalid", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 343, __extension__ __PRETTY_FUNCTION__))
;
344 if (IsOnePastTheEnd)
345 return true;
346 if (!isMostDerivedAnUnsizedArray() && MostDerivedIsArrayElement &&
347 Entries[MostDerivedPathLength - 1].getAsArrayIndex() ==
348 MostDerivedArraySize)
349 return true;
350 return false;
351 }
352
353 /// Get the range of valid index adjustments in the form
354 /// {maximum value that can be subtracted from this pointer,
355 /// maximum value that can be added to this pointer}
356 std::pair<uint64_t, uint64_t> validIndexAdjustments() {
357 if (Invalid || isMostDerivedAnUnsizedArray())
358 return {0, 0};
359
360 // [expr.add]p4: For the purposes of these operators, a pointer to a
361 // nonarray object behaves the same as a pointer to the first element of
362 // an array of length one with the type of the object as its element type.
363 bool IsArray = MostDerivedPathLength == Entries.size() &&
364 MostDerivedIsArrayElement;
365 uint64_t ArrayIndex = IsArray ? Entries.back().getAsArrayIndex()
366 : (uint64_t)IsOnePastTheEnd;
367 uint64_t ArraySize =
368 IsArray ? getMostDerivedArraySize() : (uint64_t)1;
369 return {ArrayIndex, ArraySize - ArrayIndex};
370 }
371
372 /// Check that this refers to a valid subobject.
373 bool isValidSubobject() const {
374 if (Invalid)
375 return false;
376 return !isOnePastTheEnd();
377 }
378 /// Check that this refers to a valid subobject, and if not, produce a
379 /// relevant diagnostic and set the designator as invalid.
380 bool checkSubobject(EvalInfo &Info, const Expr *E, CheckSubobjectKind CSK);
381
382 /// Get the type of the designated object.
383 QualType getType(ASTContext &Ctx) const {
384 assert(!Invalid && "invalid designator has no subobject type")(static_cast <bool> (!Invalid && "invalid designator has no subobject type"
) ? void (0) : __assert_fail ("!Invalid && \"invalid designator has no subobject type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 384, __extension__ __PRETTY_FUNCTION__))
;
385 return MostDerivedPathLength == Entries.size()
386 ? MostDerivedType
387 : Ctx.getRecordType(getAsBaseClass(Entries.back()));
388 }
389
390 /// Update this designator to refer to the first element within this array.
391 void addArrayUnchecked(const ConstantArrayType *CAT) {
392 Entries.push_back(PathEntry::ArrayIndex(0));
393
394 // This is a most-derived object.
395 MostDerivedType = CAT->getElementType();
396 MostDerivedIsArrayElement = true;
397 MostDerivedArraySize = CAT->getSize().getZExtValue();
398 MostDerivedPathLength = Entries.size();
399 }
400 /// Update this designator to refer to the first element within the array of
401 /// elements of type T. This is an array of unknown size.
402 void addUnsizedArrayUnchecked(QualType ElemTy) {
403 Entries.push_back(PathEntry::ArrayIndex(0));
404
405 MostDerivedType = ElemTy;
406 MostDerivedIsArrayElement = true;
407 // The value in MostDerivedArraySize is undefined in this case. So, set it
408 // to an arbitrary value that's likely to loudly break things if it's
409 // used.
410 MostDerivedArraySize = AssumedSizeForUnsizedArray;
411 MostDerivedPathLength = Entries.size();
412 }
413 /// Update this designator to refer to the given base or member of this
414 /// object.
415 void addDeclUnchecked(const Decl *D, bool Virtual = false) {
416 Entries.push_back(APValue::BaseOrMemberType(D, Virtual));
417
418 // If this isn't a base class, it's a new most-derived object.
419 if (const FieldDecl *FD = dyn_cast<FieldDecl>(D)) {
420 MostDerivedType = FD->getType();
421 MostDerivedIsArrayElement = false;
422 MostDerivedArraySize = 0;
423 MostDerivedPathLength = Entries.size();
424 }
425 }
426 /// Update this designator to refer to the given complex component.
427 void addComplexUnchecked(QualType EltTy, bool Imag) {
428 Entries.push_back(PathEntry::ArrayIndex(Imag));
429
430 // This is technically a most-derived object, though in practice this
431 // is unlikely to matter.
432 MostDerivedType = EltTy;
433 MostDerivedIsArrayElement = true;
434 MostDerivedArraySize = 2;
435 MostDerivedPathLength = Entries.size();
436 }
437 void diagnoseUnsizedArrayPointerArithmetic(EvalInfo &Info, const Expr *E);
438 void diagnosePointerArithmetic(EvalInfo &Info, const Expr *E,
439 const APSInt &N);
440 /// Add N to the address of this subobject.
441 void adjustIndex(EvalInfo &Info, const Expr *E, APSInt N) {
442 if (Invalid || !N) return;
443 uint64_t TruncatedN = N.extOrTrunc(64).getZExtValue();
444 if (isMostDerivedAnUnsizedArray()) {
445 diagnoseUnsizedArrayPointerArithmetic(Info, E);
446 // Can't verify -- trust that the user is doing the right thing (or if
447 // not, trust that the caller will catch the bad behavior).
448 // FIXME: Should we reject if this overflows, at least?
449 Entries.back() = PathEntry::ArrayIndex(
450 Entries.back().getAsArrayIndex() + TruncatedN);
451 return;
452 }
453
454 // [expr.add]p4: For the purposes of these operators, a pointer to a
455 // nonarray object behaves the same as a pointer to the first element of
456 // an array of length one with the type of the object as its element type.
457 bool IsArray = MostDerivedPathLength == Entries.size() &&
458 MostDerivedIsArrayElement;
459 uint64_t ArrayIndex = IsArray ? Entries.back().getAsArrayIndex()
460 : (uint64_t)IsOnePastTheEnd;
461 uint64_t ArraySize =
462 IsArray ? getMostDerivedArraySize() : (uint64_t)1;
463
464 if (N < -(int64_t)ArrayIndex || N > ArraySize - ArrayIndex) {
465 // Calculate the actual index in a wide enough type, so we can include
466 // it in the note.
467 N = N.extend(std::max<unsigned>(N.getBitWidth() + 1, 65));
468 (llvm::APInt&)N += ArrayIndex;
469 assert(N.ugt(ArraySize) && "bounds check failed for in-bounds index")(static_cast <bool> (N.ugt(ArraySize) && "bounds check failed for in-bounds index"
) ? void (0) : __assert_fail ("N.ugt(ArraySize) && \"bounds check failed for in-bounds index\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 469, __extension__ __PRETTY_FUNCTION__))
;
470 diagnosePointerArithmetic(Info, E, N);
471 setInvalid();
472 return;
473 }
474
475 ArrayIndex += TruncatedN;
476 assert(ArrayIndex <= ArraySize &&(static_cast <bool> (ArrayIndex <= ArraySize &&
"bounds check succeeded for out-of-bounds index") ? void (0)
: __assert_fail ("ArrayIndex <= ArraySize && \"bounds check succeeded for out-of-bounds index\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 477, __extension__ __PRETTY_FUNCTION__))
477 "bounds check succeeded for out-of-bounds index")(static_cast <bool> (ArrayIndex <= ArraySize &&
"bounds check succeeded for out-of-bounds index") ? void (0)
: __assert_fail ("ArrayIndex <= ArraySize && \"bounds check succeeded for out-of-bounds index\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 477, __extension__ __PRETTY_FUNCTION__))
;
478
479 if (IsArray)
480 Entries.back() = PathEntry::ArrayIndex(ArrayIndex);
481 else
482 IsOnePastTheEnd = (ArrayIndex != 0);
483 }
484 };
485
486 /// A scope at the end of which an object can need to be destroyed.
487 enum class ScopeKind {
488 Block,
489 FullExpression,
490 Call
491 };
492
493 /// A reference to a particular call and its arguments.
494 struct CallRef {
495 CallRef() : OrigCallee(), CallIndex(0), Version() {}
496 CallRef(const FunctionDecl *Callee, unsigned CallIndex, unsigned Version)
497 : OrigCallee(Callee), CallIndex(CallIndex), Version(Version) {}
498
499 explicit operator bool() const { return OrigCallee; }
500
501 /// Get the parameter that the caller initialized, corresponding to the
502 /// given parameter in the callee.
503 const ParmVarDecl *getOrigParam(const ParmVarDecl *PVD) const {
504 return OrigCallee ? OrigCallee->getParamDecl(PVD->getFunctionScopeIndex())
505 : PVD;
506 }
507
508 /// The callee at the point where the arguments were evaluated. This might
509 /// be different from the actual callee (a different redeclaration, or a
510 /// virtual override), but this function's parameters are the ones that
511 /// appear in the parameter map.
512 const FunctionDecl *OrigCallee;
513 /// The call index of the frame that holds the argument values.
514 unsigned CallIndex;
515 /// The version of the parameters corresponding to this call.
516 unsigned Version;
517 };
518
519 /// A stack frame in the constexpr call stack.
520 class CallStackFrame : public interp::Frame {
521 public:
522 EvalInfo &Info;
523
524 /// Parent - The caller of this stack frame.
525 CallStackFrame *Caller;
526
527 /// Callee - The function which was called.
528 const FunctionDecl *Callee;
529
530 /// This - The binding for the this pointer in this call, if any.
531 const LValue *This;
532
533 /// Information on how to find the arguments to this call. Our arguments
534 /// are stored in our parent's CallStackFrame, using the ParmVarDecl* as a
535 /// key and this value as the version.
536 CallRef Arguments;
537
538 /// Source location information about the default argument or default
539 /// initializer expression we're evaluating, if any.
540 CurrentSourceLocExprScope CurSourceLocExprScope;
541
542 // Note that we intentionally use std::map here so that references to
543 // values are stable.
544 typedef std::pair<const void *, unsigned> MapKeyTy;
545 typedef std::map<MapKeyTy, APValue> MapTy;
546 /// Temporaries - Temporary lvalues materialized within this stack frame.
547 MapTy Temporaries;
548
549 /// CallLoc - The location of the call expression for this call.
550 SourceLocation CallLoc;
551
552 /// Index - The call index of this call.
553 unsigned Index;
554
555 /// The stack of integers for tracking version numbers for temporaries.
556 SmallVector<unsigned, 2> TempVersionStack = {1};
557 unsigned CurTempVersion = TempVersionStack.back();
558
559 unsigned getTempVersion() const { return TempVersionStack.back(); }
560
561 void pushTempVersion() {
562 TempVersionStack.push_back(++CurTempVersion);
563 }
564
565 void popTempVersion() {
566 TempVersionStack.pop_back();
567 }
568
569 CallRef createCall(const FunctionDecl *Callee) {
570 return {Callee, Index, ++CurTempVersion};
571 }
572
573 // FIXME: Adding this to every 'CallStackFrame' may have a nontrivial impact
574 // on the overall stack usage of deeply-recursing constexpr evaluations.
575 // (We should cache this map rather than recomputing it repeatedly.)
576 // But let's try this and see how it goes; we can look into caching the map
577 // as a later change.
578
579 /// LambdaCaptureFields - Mapping from captured variables/this to
580 /// corresponding data members in the closure class.
581 llvm::DenseMap<const VarDecl *, FieldDecl *> LambdaCaptureFields;
582 FieldDecl *LambdaThisCaptureField;
583
584 CallStackFrame(EvalInfo &Info, SourceLocation CallLoc,
585 const FunctionDecl *Callee, const LValue *This,
586 CallRef Arguments);
587 ~CallStackFrame();
588
589 // Return the temporary for Key whose version number is Version.
590 APValue *getTemporary(const void *Key, unsigned Version) {
591 MapKeyTy KV(Key, Version);
592 auto LB = Temporaries.lower_bound(KV);
593 if (LB != Temporaries.end() && LB->first == KV)
594 return &LB->second;
595 // Pair (Key,Version) wasn't found in the map. Check that no elements
596 // in the map have 'Key' as their key.
597 assert((LB == Temporaries.end() || LB->first.first != Key) &&(static_cast <bool> ((LB == Temporaries.end() || LB->
first.first != Key) && (LB == Temporaries.begin() || std
::prev(LB)->first.first != Key) && "Element with key 'Key' found in map"
) ? 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-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 599, __extension__ __PRETTY_FUNCTION__))
598 (LB == Temporaries.begin() || std::prev(LB)->first.first != Key) &&(static_cast <bool> ((LB == Temporaries.end() || LB->
first.first != Key) && (LB == Temporaries.begin() || std
::prev(LB)->first.first != Key) && "Element with key 'Key' found in map"
) ? 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-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 599, __extension__ __PRETTY_FUNCTION__))
599 "Element with key 'Key' found in map")(static_cast <bool> ((LB == Temporaries.end() || LB->
first.first != Key) && (LB == Temporaries.begin() || std
::prev(LB)->first.first != Key) && "Element with key 'Key' found in map"
) ? 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-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 599, __extension__ __PRETTY_FUNCTION__))
;
600 return nullptr;
601 }
602
603 // Return the current temporary for Key in the map.
604 APValue *getCurrentTemporary(const void *Key) {
605 auto UB = Temporaries.upper_bound(MapKeyTy(Key, UINT_MAX(2147483647 *2U +1U)));
606 if (UB != Temporaries.begin() && std::prev(UB)->first.first == Key)
607 return &std::prev(UB)->second;
608 return nullptr;
609 }
610
611 // Return the version number of the current temporary for Key.
612 unsigned getCurrentTemporaryVersion(const void *Key) const {
613 auto UB = Temporaries.upper_bound(MapKeyTy(Key, UINT_MAX(2147483647 *2U +1U)));
614 if (UB != Temporaries.begin() && std::prev(UB)->first.first == Key)
615 return std::prev(UB)->first.second;
616 return 0;
617 }
618
619 /// Allocate storage for an object of type T in this stack frame.
620 /// Populates LV with a handle to the created object. Key identifies
621 /// the temporary within the stack frame, and must not be reused without
622 /// bumping the temporary version number.
623 template<typename KeyT>
624 APValue &createTemporary(const KeyT *Key, QualType T,
625 ScopeKind Scope, LValue &LV);
626
627 /// Allocate storage for a parameter of a function call made in this frame.
628 APValue &createParam(CallRef Args, const ParmVarDecl *PVD, LValue &LV);
629
630 void describe(llvm::raw_ostream &OS) override;
631
632 Frame *getCaller() const override { return Caller; }
633 SourceLocation getCallLocation() const override { return CallLoc; }
634 const FunctionDecl *getCallee() const override { return Callee; }
635
636 bool isStdFunction() const {
637 for (const DeclContext *DC = Callee; DC; DC = DC->getParent())
638 if (DC->isStdNamespace())
639 return true;
640 return false;
641 }
642
643 private:
644 APValue &createLocal(APValue::LValueBase Base, const void *Key, QualType T,
645 ScopeKind Scope);
646 };
647
648 /// Temporarily override 'this'.
649 class ThisOverrideRAII {
650 public:
651 ThisOverrideRAII(CallStackFrame &Frame, const LValue *NewThis, bool Enable)
652 : Frame(Frame), OldThis(Frame.This) {
653 if (Enable)
654 Frame.This = NewThis;
655 }
656 ~ThisOverrideRAII() {
657 Frame.This = OldThis;
658 }
659 private:
660 CallStackFrame &Frame;
661 const LValue *OldThis;
662 };
663}
664
665static bool HandleDestruction(EvalInfo &Info, const Expr *E,
666 const LValue &This, QualType ThisType);
667static bool HandleDestruction(EvalInfo &Info, SourceLocation Loc,
668 APValue::LValueBase LVBase, APValue &Value,
669 QualType T);
670
671namespace {
672 /// A cleanup, and a flag indicating whether it is lifetime-extended.
673 class Cleanup {
674 llvm::PointerIntPair<APValue*, 2, ScopeKind> Value;
675 APValue::LValueBase Base;
676 QualType T;
677
678 public:
679 Cleanup(APValue *Val, APValue::LValueBase Base, QualType T,
680 ScopeKind Scope)
681 : Value(Val, Scope), Base(Base), T(T) {}
682
683 /// Determine whether this cleanup should be performed at the end of the
684 /// given kind of scope.
685 bool isDestroyedAtEndOf(ScopeKind K) const {
686 return (int)Value.getInt() >= (int)K;
687 }
688 bool endLifetime(EvalInfo &Info, bool RunDestructors) {
689 if (RunDestructors) {
690 SourceLocation Loc;
691 if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>())
692 Loc = VD->getLocation();
693 else if (const Expr *E = Base.dyn_cast<const Expr*>())
694 Loc = E->getExprLoc();
695 return HandleDestruction(Info, Loc, Base, *Value.getPointer(), T);
696 }
697 *Value.getPointer() = APValue();
698 return true;
699 }
700
701 bool hasSideEffect() {
702 return T.isDestructedType();
703 }
704 };
705
706 /// A reference to an object whose construction we are currently evaluating.
707 struct ObjectUnderConstruction {
708 APValue::LValueBase Base;
709 ArrayRef<APValue::LValuePathEntry> Path;
710 friend bool operator==(const ObjectUnderConstruction &LHS,
711 const ObjectUnderConstruction &RHS) {
712 return LHS.Base == RHS.Base && LHS.Path == RHS.Path;
713 }
714 friend llvm::hash_code hash_value(const ObjectUnderConstruction &Obj) {
715 return llvm::hash_combine(Obj.Base, Obj.Path);
716 }
717 };
718 enum class ConstructionPhase {
719 None,
720 Bases,
721 AfterBases,
722 AfterFields,
723 Destroying,
724 DestroyingBases
725 };
726}
727
728namespace llvm {
729template<> struct DenseMapInfo<ObjectUnderConstruction> {
730 using Base = DenseMapInfo<APValue::LValueBase>;
731 static ObjectUnderConstruction getEmptyKey() {
732 return {Base::getEmptyKey(), {}}; }
733 static ObjectUnderConstruction getTombstoneKey() {
734 return {Base::getTombstoneKey(), {}};
735 }
736 static unsigned getHashValue(const ObjectUnderConstruction &Object) {
737 return hash_value(Object);
738 }
739 static bool isEqual(const ObjectUnderConstruction &LHS,
740 const ObjectUnderConstruction &RHS) {
741 return LHS == RHS;
742 }
743};
744}
745
746namespace {
747 /// A dynamically-allocated heap object.
748 struct DynAlloc {
749 /// The value of this heap-allocated object.
750 APValue Value;
751 /// The allocating expression; used for diagnostics. Either a CXXNewExpr
752 /// or a CallExpr (the latter is for direct calls to operator new inside
753 /// std::allocator<T>::allocate).
754 const Expr *AllocExpr = nullptr;
755
756 enum Kind {
757 New,
758 ArrayNew,
759 StdAllocator
760 };
761
762 /// Get the kind of the allocation. This must match between allocation
763 /// and deallocation.
764 Kind getKind() const {
765 if (auto *NE = dyn_cast<CXXNewExpr>(AllocExpr))
766 return NE->isArray() ? ArrayNew : New;
767 assert(isa<CallExpr>(AllocExpr))(static_cast <bool> (isa<CallExpr>(AllocExpr)) ? void
(0) : __assert_fail ("isa<CallExpr>(AllocExpr)", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 767, __extension__ __PRETTY_FUNCTION__))
;
768 return StdAllocator;
769 }
770 };
771
772 struct DynAllocOrder {
773 bool operator()(DynamicAllocLValue L, DynamicAllocLValue R) const {
774 return L.getIndex() < R.getIndex();
775 }
776 };
777
778 /// EvalInfo - This is a private struct used by the evaluator to capture
779 /// information about a subexpression as it is folded. It retains information
780 /// about the AST context, but also maintains information about the folded
781 /// expression.
782 ///
783 /// If an expression could be evaluated, it is still possible it is not a C
784 /// "integer constant expression" or constant expression. If not, this struct
785 /// captures information about how and why not.
786 ///
787 /// One bit of information passed *into* the request for constant folding
788 /// indicates whether the subexpression is "evaluated" or not according to C
789 /// rules. For example, the RHS of (0 && foo()) is not evaluated. We can
790 /// evaluate the expression regardless of what the RHS is, but C only allows
791 /// certain things in certain situations.
792 class EvalInfo : public interp::State {
793 public:
794 ASTContext &Ctx;
795
796 /// EvalStatus - Contains information about the evaluation.
797 Expr::EvalStatus &EvalStatus;
798
799 /// CurrentCall - The top of the constexpr call stack.
800 CallStackFrame *CurrentCall;
801
802 /// CallStackDepth - The number of calls in the call stack right now.
803 unsigned CallStackDepth;
804
805 /// NextCallIndex - The next call index to assign.
806 unsigned NextCallIndex;
807
808 /// StepsLeft - The remaining number of evaluation steps we're permitted
809 /// to perform. This is essentially a limit for the number of statements
810 /// we will evaluate.
811 unsigned StepsLeft;
812
813 /// Enable the experimental new constant interpreter. If an expression is
814 /// not supported by the interpreter, an error is triggered.
815 bool EnableNewConstInterp;
816
817 /// BottomFrame - The frame in which evaluation started. This must be
818 /// initialized after CurrentCall and CallStackDepth.
819 CallStackFrame BottomFrame;
820
821 /// A stack of values whose lifetimes end at the end of some surrounding
822 /// evaluation frame.
823 llvm::SmallVector<Cleanup, 16> CleanupStack;
824
825 /// EvaluatingDecl - This is the declaration whose initializer is being
826 /// evaluated, if any.
827 APValue::LValueBase EvaluatingDecl;
828
829 enum class EvaluatingDeclKind {
830 None,
831 /// We're evaluating the construction of EvaluatingDecl.
832 Ctor,
833 /// We're evaluating the destruction of EvaluatingDecl.
834 Dtor,
835 };
836 EvaluatingDeclKind IsEvaluatingDecl = EvaluatingDeclKind::None;
837
838 /// EvaluatingDeclValue - This is the value being constructed for the
839 /// declaration whose initializer is being evaluated, if any.
840 APValue *EvaluatingDeclValue;
841
842 /// Set of objects that are currently being constructed.
843 llvm::DenseMap<ObjectUnderConstruction, ConstructionPhase>
844 ObjectsUnderConstruction;
845
846 /// Current heap allocations, along with the location where each was
847 /// allocated. We use std::map here because we need stable addresses
848 /// for the stored APValues.
849 std::map<DynamicAllocLValue, DynAlloc, DynAllocOrder> HeapAllocs;
850
851 /// The number of heap allocations performed so far in this evaluation.
852 unsigned NumHeapAllocs = 0;
853
854 struct EvaluatingConstructorRAII {
855 EvalInfo &EI;
856 ObjectUnderConstruction Object;
857 bool DidInsert;
858 EvaluatingConstructorRAII(EvalInfo &EI, ObjectUnderConstruction Object,
859 bool HasBases)
860 : EI(EI), Object(Object) {
861 DidInsert =
862 EI.ObjectsUnderConstruction
863 .insert({Object, HasBases ? ConstructionPhase::Bases
864 : ConstructionPhase::AfterBases})
865 .second;
866 }
867 void finishedConstructingBases() {
868 EI.ObjectsUnderConstruction[Object] = ConstructionPhase::AfterBases;
869 }
870 void finishedConstructingFields() {
871 EI.ObjectsUnderConstruction[Object] = ConstructionPhase::AfterFields;
872 }
873 ~EvaluatingConstructorRAII() {
874 if (DidInsert) EI.ObjectsUnderConstruction.erase(Object);
875 }
876 };
877
878 struct EvaluatingDestructorRAII {
879 EvalInfo &EI;
880 ObjectUnderConstruction Object;
881 bool DidInsert;
882 EvaluatingDestructorRAII(EvalInfo &EI, ObjectUnderConstruction Object)
883 : EI(EI), Object(Object) {
884 DidInsert = EI.ObjectsUnderConstruction
885 .insert({Object, ConstructionPhase::Destroying})
886 .second;
887 }
888 void startedDestroyingBases() {
889 EI.ObjectsUnderConstruction[Object] =
890 ConstructionPhase::DestroyingBases;
891 }
892 ~EvaluatingDestructorRAII() {
893 if (DidInsert)
894 EI.ObjectsUnderConstruction.erase(Object);
895 }
896 };
897
898 ConstructionPhase
899 isEvaluatingCtorDtor(APValue::LValueBase Base,
900 ArrayRef<APValue::LValuePathEntry> Path) {
901 return ObjectsUnderConstruction.lookup({Base, Path});
902 }
903
904 /// If we're currently speculatively evaluating, the outermost call stack
905 /// depth at which we can mutate state, otherwise 0.
906 unsigned SpeculativeEvaluationDepth = 0;
907
908 /// The current array initialization index, if we're performing array
909 /// initialization.
910 uint64_t ArrayInitIndex = -1;
911
912 /// HasActiveDiagnostic - Was the previous diagnostic stored? If so, further
913 /// notes attached to it will also be stored, otherwise they will not be.
914 bool HasActiveDiagnostic;
915
916 /// Have we emitted a diagnostic explaining why we couldn't constant
917 /// fold (not just why it's not strictly a constant expression)?
918 bool HasFoldFailureDiagnostic;
919
920 /// Whether or not we're in a context where the front end requires a
921 /// constant value.
922 bool InConstantContext;
923
924 /// Whether we're checking that an expression is a potential constant
925 /// expression. If so, do not fail on constructs that could become constant
926 /// later on (such as a use of an undefined global).
927 bool CheckingPotentialConstantExpression = false;
928
929 /// Whether we're checking for an expression that has undefined behavior.
930 /// If so, we will produce warnings if we encounter an operation that is
931 /// always undefined.
932 ///
933 /// Note that we still need to evaluate the expression normally when this
934 /// is set; this is used when evaluating ICEs in C.
935 bool CheckingForUndefinedBehavior = false;
936
937 enum EvaluationMode {
938 /// Evaluate as a constant expression. Stop if we find that the expression
939 /// is not a constant expression.
940 EM_ConstantExpression,
941
942 /// Evaluate as a constant expression. Stop if we find that the expression
943 /// is not a constant expression. Some expressions can be retried in the
944 /// optimizer if we don't constant fold them here, but in an unevaluated
945 /// context we try to fold them immediately since the optimizer never
946 /// gets a chance to look at it.
947 EM_ConstantExpressionUnevaluated,
948
949 /// Fold the expression to a constant. Stop if we hit a side-effect that
950 /// we can't model.
951 EM_ConstantFold,
952
953 /// Evaluate in any way we know how. Don't worry about side-effects that
954 /// can't be modeled.
955 EM_IgnoreSideEffects,
956 } EvalMode;
957
958 /// Are we checking whether the expression is a potential constant
959 /// expression?
960 bool checkingPotentialConstantExpression() const override {
961 return CheckingPotentialConstantExpression;
962 }
963
964 /// Are we checking an expression for overflow?
965 // FIXME: We should check for any kind of undefined or suspicious behavior
966 // in such constructs, not just overflow.
967 bool checkingForUndefinedBehavior() const override {
968 return CheckingForUndefinedBehavior;
969 }
970
971 EvalInfo(const ASTContext &C, Expr::EvalStatus &S, EvaluationMode Mode)
972 : Ctx(const_cast<ASTContext &>(C)), EvalStatus(S), CurrentCall(nullptr),
973 CallStackDepth(0), NextCallIndex(1),
974 StepsLeft(C.getLangOpts().ConstexprStepLimit),
975 EnableNewConstInterp(C.getLangOpts().EnableNewConstInterp),
976 BottomFrame(*this, SourceLocation(), nullptr, nullptr, CallRef()),
977 EvaluatingDecl((const ValueDecl *)nullptr),
978 EvaluatingDeclValue(nullptr), HasActiveDiagnostic(false),
979 HasFoldFailureDiagnostic(false), InConstantContext(false),
980 EvalMode(Mode) {}
981
982 ~EvalInfo() {
983 discardCleanups();
984 }
985
986 void setEvaluatingDecl(APValue::LValueBase Base, APValue &Value,
987 EvaluatingDeclKind EDK = EvaluatingDeclKind::Ctor) {
988 EvaluatingDecl = Base;
989 IsEvaluatingDecl = EDK;
990 EvaluatingDeclValue = &Value;
991 }
992
993 bool CheckCallLimit(SourceLocation Loc) {
994 // Don't perform any constexpr calls (other than the call we're checking)
995 // when checking a potential constant expression.
996 if (checkingPotentialConstantExpression() && CallStackDepth > 1)
997 return false;
998 if (NextCallIndex == 0) {
999 // NextCallIndex has wrapped around.
1000 FFDiag(Loc, diag::note_constexpr_call_limit_exceeded);
1001 return false;
1002 }
1003 if (CallStackDepth <= getLangOpts().ConstexprCallDepth)
1004 return true;
1005 FFDiag(Loc, diag::note_constexpr_depth_limit_exceeded)
1006 << getLangOpts().ConstexprCallDepth;
1007 return false;
1008 }
1009
1010 std::pair<CallStackFrame *, unsigned>
1011 getCallFrameAndDepth(unsigned CallIndex) {
1012 assert(CallIndex && "no call index in getCallFrameAndDepth")(static_cast <bool> (CallIndex && "no call index in getCallFrameAndDepth"
) ? void (0) : __assert_fail ("CallIndex && \"no call index in getCallFrameAndDepth\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1012, __extension__ __PRETTY_FUNCTION__))
;
1013 // We will eventually hit BottomFrame, which has Index 1, so Frame can't
1014 // be null in this loop.
1015 unsigned Depth = CallStackDepth;
1016 CallStackFrame *Frame = CurrentCall;
1017 while (Frame->Index > CallIndex) {
1018 Frame = Frame->Caller;
1019 --Depth;
1020 }
1021 if (Frame->Index == CallIndex)
1022 return {Frame, Depth};
1023 return {nullptr, 0};
1024 }
1025
1026 bool nextStep(const Stmt *S) {
1027 if (!StepsLeft) {
1028 FFDiag(S->getBeginLoc(), diag::note_constexpr_step_limit_exceeded);
1029 return false;
1030 }
1031 --StepsLeft;
1032 return true;
1033 }
1034
1035 APValue *createHeapAlloc(const Expr *E, QualType T, LValue &LV);
1036
1037 Optional<DynAlloc*> lookupDynamicAlloc(DynamicAllocLValue DA) {
1038 Optional<DynAlloc*> Result;
1039 auto It = HeapAllocs.find(DA);
1040 if (It != HeapAllocs.end())
1041 Result = &It->second;
1042 return Result;
1043 }
1044
1045 /// Get the allocated storage for the given parameter of the given call.
1046 APValue *getParamSlot(CallRef Call, const ParmVarDecl *PVD) {
1047 CallStackFrame *Frame = getCallFrameAndDepth(Call.CallIndex).first;
1048 return Frame ? Frame->getTemporary(Call.getOrigParam(PVD), Call.Version)
1049 : nullptr;
1050 }
1051
1052 /// Information about a stack frame for std::allocator<T>::[de]allocate.
1053 struct StdAllocatorCaller {
1054 unsigned FrameIndex;
1055 QualType ElemType;
1056 explicit operator bool() const { return FrameIndex != 0; };
1057 };
1058
1059 StdAllocatorCaller getStdAllocatorCaller(StringRef FnName) const {
1060 for (const CallStackFrame *Call = CurrentCall; Call != &BottomFrame;
1061 Call = Call->Caller) {
1062 const auto *MD = dyn_cast_or_null<CXXMethodDecl>(Call->Callee);
1063 if (!MD)
1064 continue;
1065 const IdentifierInfo *FnII = MD->getIdentifier();
1066 if (!FnII || !FnII->isStr(FnName))
1067 continue;
1068
1069 const auto *CTSD =
1070 dyn_cast<ClassTemplateSpecializationDecl>(MD->getParent());
1071 if (!CTSD)
1072 continue;
1073
1074 const IdentifierInfo *ClassII = CTSD->getIdentifier();
1075 const TemplateArgumentList &TAL = CTSD->getTemplateArgs();
1076 if (CTSD->isInStdNamespace() && ClassII &&
1077 ClassII->isStr("allocator") && TAL.size() >= 1 &&
1078 TAL[0].getKind() == TemplateArgument::Type)
1079 return {Call->Index, TAL[0].getAsType()};
1080 }
1081
1082 return {};
1083 }
1084
1085 void performLifetimeExtension() {
1086 // Disable the cleanups for lifetime-extended temporaries.
1087 llvm::erase_if(CleanupStack, [](Cleanup &C) {
1088 return !C.isDestroyedAtEndOf(ScopeKind::FullExpression);
1089 });
1090 }
1091
1092 /// Throw away any remaining cleanups at the end of evaluation. If any
1093 /// cleanups would have had a side-effect, note that as an unmodeled
1094 /// side-effect and return false. Otherwise, return true.
1095 bool discardCleanups() {
1096 for (Cleanup &C : CleanupStack) {
1097 if (C.hasSideEffect() && !noteSideEffect()) {
1098 CleanupStack.clear();
1099 return false;
1100 }
1101 }
1102 CleanupStack.clear();
1103 return true;
1104 }
1105
1106 private:
1107 interp::Frame *getCurrentFrame() override { return CurrentCall; }
1108 const interp::Frame *getBottomFrame() const override { return &BottomFrame; }
1109
1110 bool hasActiveDiagnostic() override { return HasActiveDiagnostic; }
1111 void setActiveDiagnostic(bool Flag) override { HasActiveDiagnostic = Flag; }
1112
1113 void setFoldFailureDiagnostic(bool Flag) override {
1114 HasFoldFailureDiagnostic = Flag;
1115 }
1116
1117 Expr::EvalStatus &getEvalStatus() const override { return EvalStatus; }
1118
1119 ASTContext &getCtx() const override { return Ctx; }
1120
1121 // If we have a prior diagnostic, it will be noting that the expression
1122 // isn't a constant expression. This diagnostic is more important,
1123 // unless we require this evaluation to produce a constant expression.
1124 //
1125 // FIXME: We might want to show both diagnostics to the user in
1126 // EM_ConstantFold mode.
1127 bool hasPriorDiagnostic() override {
1128 if (!EvalStatus.Diag->empty()) {
1129 switch (EvalMode) {
1130 case EM_ConstantFold:
1131 case EM_IgnoreSideEffects:
1132 if (!HasFoldFailureDiagnostic)
1133 break;
1134 // We've already failed to fold something. Keep that diagnostic.
1135 LLVM_FALLTHROUGH[[gnu::fallthrough]];
1136 case EM_ConstantExpression:
1137 case EM_ConstantExpressionUnevaluated:
1138 setActiveDiagnostic(false);
1139 return true;
1140 }
1141 }
1142 return false;
1143 }
1144
1145 unsigned getCallStackDepth() override { return CallStackDepth; }
1146
1147 public:
1148 /// Should we continue evaluation after encountering a side-effect that we
1149 /// couldn't model?
1150 bool keepEvaluatingAfterSideEffect() {
1151 switch (EvalMode) {
1152 case EM_IgnoreSideEffects:
1153 return true;
1154
1155 case EM_ConstantExpression:
1156 case EM_ConstantExpressionUnevaluated:
1157 case EM_ConstantFold:
1158 // By default, assume any side effect might be valid in some other
1159 // evaluation of this expression from a different context.
1160 return checkingPotentialConstantExpression() ||
1161 checkingForUndefinedBehavior();
1162 }
1163 llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1163)
;
1164 }
1165
1166 /// Note that we have had a side-effect, and determine whether we should
1167 /// keep evaluating.
1168 bool noteSideEffect() {
1169 EvalStatus.HasSideEffects = true;
1170 return keepEvaluatingAfterSideEffect();
1171 }
1172
1173 /// Should we continue evaluation after encountering undefined behavior?
1174 bool keepEvaluatingAfterUndefinedBehavior() {
1175 switch (EvalMode) {
1176 case EM_IgnoreSideEffects:
1177 case EM_ConstantFold:
1178 return true;
1179
1180 case EM_ConstantExpression:
1181 case EM_ConstantExpressionUnevaluated:
1182 return checkingForUndefinedBehavior();
1183 }
1184 llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1184)
;
1185 }
1186
1187 /// Note that we hit something that was technically undefined behavior, but
1188 /// that we can evaluate past it (such as signed overflow or floating-point
1189 /// division by zero.)
1190 bool noteUndefinedBehavior() override {
1191 EvalStatus.HasUndefinedBehavior = true;
1192 return keepEvaluatingAfterUndefinedBehavior();
1193 }
1194
1195 /// Should we continue evaluation as much as possible after encountering a
1196 /// construct which can't be reduced to a value?
1197 bool keepEvaluatingAfterFailure() const override {
1198 if (!StepsLeft)
1199 return false;
1200
1201 switch (EvalMode) {
1202 case EM_ConstantExpression:
1203 case EM_ConstantExpressionUnevaluated:
1204 case EM_ConstantFold:
1205 case EM_IgnoreSideEffects:
1206 return checkingPotentialConstantExpression() ||
1207 checkingForUndefinedBehavior();
1208 }
1209 llvm_unreachable("Missed EvalMode case")::llvm::llvm_unreachable_internal("Missed EvalMode case", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1209)
;
1210 }
1211
1212 /// Notes that we failed to evaluate an expression that other expressions
1213 /// directly depend on, and determine if we should keep evaluating. This
1214 /// should only be called if we actually intend to keep evaluating.
1215 ///
1216 /// Call noteSideEffect() instead if we may be able to ignore the value that
1217 /// we failed to evaluate, e.g. if we failed to evaluate Foo() in:
1218 ///
1219 /// (Foo(), 1) // use noteSideEffect
1220 /// (Foo() || true) // use noteSideEffect
1221 /// Foo() + 1 // use noteFailure
1222 LLVM_NODISCARD[[clang::warn_unused_result]] bool noteFailure() {
1223 // Failure when evaluating some expression often means there is some
1224 // subexpression whose evaluation was skipped. Therefore, (because we
1225 // don't track whether we skipped an expression when unwinding after an
1226 // evaluation failure) every evaluation failure that bubbles up from a
1227 // subexpression implies that a side-effect has potentially happened. We
1228 // skip setting the HasSideEffects flag to true until we decide to
1229 // continue evaluating after that point, which happens here.
1230 bool KeepGoing = keepEvaluatingAfterFailure();
1231 EvalStatus.HasSideEffects |= KeepGoing;
1232 return KeepGoing;
1233 }
1234
1235 class ArrayInitLoopIndex {
1236 EvalInfo &Info;
1237 uint64_t OuterIndex;
1238
1239 public:
1240 ArrayInitLoopIndex(EvalInfo &Info)
1241 : Info(Info), OuterIndex(Info.ArrayInitIndex) {
1242 Info.ArrayInitIndex = 0;
1243 }
1244 ~ArrayInitLoopIndex() { Info.ArrayInitIndex = OuterIndex; }
1245
1246 operator uint64_t&() { return Info.ArrayInitIndex; }
1247 };
1248 };
1249
1250 /// Object used to treat all foldable expressions as constant expressions.
1251 struct FoldConstant {
1252 EvalInfo &Info;
1253 bool Enabled;
1254 bool HadNoPriorDiags;
1255 EvalInfo::EvaluationMode OldMode;
1256
1257 explicit FoldConstant(EvalInfo &Info, bool Enabled)
1258 : Info(Info),
1259 Enabled(Enabled),
1260 HadNoPriorDiags(Info.EvalStatus.Diag &&
1261 Info.EvalStatus.Diag->empty() &&
1262 !Info.EvalStatus.HasSideEffects),
1263 OldMode(Info.EvalMode) {
1264 if (Enabled)
1265 Info.EvalMode = EvalInfo::EM_ConstantFold;
1266 }
1267 void keepDiagnostics() { Enabled = false; }
1268 ~FoldConstant() {
1269 if (Enabled && HadNoPriorDiags && !Info.EvalStatus.Diag->empty() &&
1270 !Info.EvalStatus.HasSideEffects)
1271 Info.EvalStatus.Diag->clear();
1272 Info.EvalMode = OldMode;
1273 }
1274 };
1275
1276 /// RAII object used to set the current evaluation mode to ignore
1277 /// side-effects.
1278 struct IgnoreSideEffectsRAII {
1279 EvalInfo &Info;
1280 EvalInfo::EvaluationMode OldMode;
1281 explicit IgnoreSideEffectsRAII(EvalInfo &Info)
1282 : Info(Info), OldMode(Info.EvalMode) {
1283 Info.EvalMode = EvalInfo::EM_IgnoreSideEffects;
1284 }
1285
1286 ~IgnoreSideEffectsRAII() { Info.EvalMode = OldMode; }
1287 };
1288
1289 /// RAII object used to optionally suppress diagnostics and side-effects from
1290 /// a speculative evaluation.
1291 class SpeculativeEvaluationRAII {
1292 EvalInfo *Info = nullptr;
1293 Expr::EvalStatus OldStatus;
1294 unsigned OldSpeculativeEvaluationDepth;
1295
1296 void moveFromAndCancel(SpeculativeEvaluationRAII &&Other) {
1297 Info = Other.Info;
1298 OldStatus = Other.OldStatus;
1299 OldSpeculativeEvaluationDepth = Other.OldSpeculativeEvaluationDepth;
1300 Other.Info = nullptr;
1301 }
1302
1303 void maybeRestoreState() {
1304 if (!Info)
1305 return;
1306
1307 Info->EvalStatus = OldStatus;
1308 Info->SpeculativeEvaluationDepth = OldSpeculativeEvaluationDepth;
1309 }
1310
1311 public:
1312 SpeculativeEvaluationRAII() = default;
1313
1314 SpeculativeEvaluationRAII(
1315 EvalInfo &Info, SmallVectorImpl<PartialDiagnosticAt> *NewDiag = nullptr)
1316 : Info(&Info), OldStatus(Info.EvalStatus),
1317 OldSpeculativeEvaluationDepth(Info.SpeculativeEvaluationDepth) {
1318 Info.EvalStatus.Diag = NewDiag;
1319 Info.SpeculativeEvaluationDepth = Info.CallStackDepth + 1;
1320 }
1321
1322 SpeculativeEvaluationRAII(const SpeculativeEvaluationRAII &Other) = delete;
1323 SpeculativeEvaluationRAII(SpeculativeEvaluationRAII &&Other) {
1324 moveFromAndCancel(std::move(Other));
1325 }
1326
1327 SpeculativeEvaluationRAII &operator=(SpeculativeEvaluationRAII &&Other) {
1328 maybeRestoreState();
1329 moveFromAndCancel(std::move(Other));
1330 return *this;
1331 }
1332
1333 ~SpeculativeEvaluationRAII() { maybeRestoreState(); }
1334 };
1335
1336 /// RAII object wrapping a full-expression or block scope, and handling
1337 /// the ending of the lifetime of temporaries created within it.
1338 template<ScopeKind Kind>
1339 class ScopeRAII {
1340 EvalInfo &Info;
1341 unsigned OldStackSize;
1342 public:
1343 ScopeRAII(EvalInfo &Info)
1344 : Info(Info), OldStackSize(Info.CleanupStack.size()) {
1345 // Push a new temporary version. This is needed to distinguish between
1346 // temporaries created in different iterations of a loop.
1347 Info.CurrentCall->pushTempVersion();
1348 }
1349 bool destroy(bool RunDestructors = true) {
1350 bool OK = cleanup(Info, RunDestructors, OldStackSize);
1351 OldStackSize = -1U;
1352 return OK;
1353 }
1354 ~ScopeRAII() {
1355 if (OldStackSize != -1U)
1356 destroy(false);
1357 // Body moved to a static method to encourage the compiler to inline away
1358 // instances of this class.
1359 Info.CurrentCall->popTempVersion();
1360 }
1361 private:
1362 static bool cleanup(EvalInfo &Info, bool RunDestructors,
1363 unsigned OldStackSize) {
1364 assert(OldStackSize <= Info.CleanupStack.size() &&(static_cast <bool> (OldStackSize <= Info.CleanupStack
.size() && "running cleanups out of order?") ? void (
0) : __assert_fail ("OldStackSize <= Info.CleanupStack.size() && \"running cleanups out of order?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1365, __extension__ __PRETTY_FUNCTION__))
1365 "running cleanups out of order?")(static_cast <bool> (OldStackSize <= Info.CleanupStack
.size() && "running cleanups out of order?") ? void (
0) : __assert_fail ("OldStackSize <= Info.CleanupStack.size() && \"running cleanups out of order?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1365, __extension__ __PRETTY_FUNCTION__))
;
1366
1367 // Run all cleanups for a block scope, and non-lifetime-extended cleanups
1368 // for a full-expression scope.
1369 bool Success = true;
1370 for (unsigned I = Info.CleanupStack.size(); I > OldStackSize; --I) {
1371 if (Info.CleanupStack[I - 1].isDestroyedAtEndOf(Kind)) {
1372 if (!Info.CleanupStack[I - 1].endLifetime(Info, RunDestructors)) {
1373 Success = false;
1374 break;
1375 }
1376 }
1377 }
1378
1379 // Compact any retained cleanups.
1380 auto NewEnd = Info.CleanupStack.begin() + OldStackSize;
1381 if (Kind != ScopeKind::Block)
1382 NewEnd =
1383 std::remove_if(NewEnd, Info.CleanupStack.end(), [](Cleanup &C) {
1384 return C.isDestroyedAtEndOf(Kind);
1385 });
1386 Info.CleanupStack.erase(NewEnd, Info.CleanupStack.end());
1387 return Success;
1388 }
1389 };
1390 typedef ScopeRAII<ScopeKind::Block> BlockScopeRAII;
1391 typedef ScopeRAII<ScopeKind::FullExpression> FullExpressionRAII;
1392 typedef ScopeRAII<ScopeKind::Call> CallScopeRAII;
1393}
1394
1395bool SubobjectDesignator::checkSubobject(EvalInfo &Info, const Expr *E,
1396 CheckSubobjectKind CSK) {
1397 if (Invalid)
1398 return false;
1399 if (isOnePastTheEnd()) {
1400 Info.CCEDiag(E, diag::note_constexpr_past_end_subobject)
1401 << CSK;
1402 setInvalid();
1403 return false;
1404 }
1405 // Note, we do not diagnose if isMostDerivedAnUnsizedArray(), because there
1406 // must actually be at least one array element; even a VLA cannot have a
1407 // bound of zero. And if our index is nonzero, we already had a CCEDiag.
1408 return true;
1409}
1410
1411void SubobjectDesignator::diagnoseUnsizedArrayPointerArithmetic(EvalInfo &Info,
1412 const Expr *E) {
1413 Info.CCEDiag(E, diag::note_constexpr_unsized_array_indexed);
1414 // Do not set the designator as invalid: we can represent this situation,
1415 // and correct handling of __builtin_object_size requires us to do so.
1416}
1417
1418void SubobjectDesignator::diagnosePointerArithmetic(EvalInfo &Info,
1419 const Expr *E,
1420 const APSInt &N) {
1421 // If we're complaining, we must be able to statically determine the size of
1422 // the most derived array.
1423 if (MostDerivedPathLength == Entries.size() && MostDerivedIsArrayElement)
1424 Info.CCEDiag(E, diag::note_constexpr_array_index)
1425 << N << /*array*/ 0
1426 << static_cast<unsigned>(getMostDerivedArraySize());
1427 else
1428 Info.CCEDiag(E, diag::note_constexpr_array_index)
1429 << N << /*non-array*/ 1;
1430 setInvalid();
1431}
1432
1433CallStackFrame::CallStackFrame(EvalInfo &Info, SourceLocation CallLoc,
1434 const FunctionDecl *Callee, const LValue *This,
1435 CallRef Call)
1436 : Info(Info), Caller(Info.CurrentCall), Callee(Callee), This(This),
1437 Arguments(Call), CallLoc(CallLoc), Index(Info.NextCallIndex++) {
1438 Info.CurrentCall = this;
1439 ++Info.CallStackDepth;
1440}
1441
1442CallStackFrame::~CallStackFrame() {
1443 assert(Info.CurrentCall == this && "calls retired out of order")(static_cast <bool> (Info.CurrentCall == this &&
"calls retired out of order") ? void (0) : __assert_fail ("Info.CurrentCall == this && \"calls retired out of order\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1443, __extension__ __PRETTY_FUNCTION__))
;
1444 --Info.CallStackDepth;
1445 Info.CurrentCall = Caller;
1446}
1447
1448static bool isRead(AccessKinds AK) {
1449 return AK == AK_Read || AK == AK_ReadObjectRepresentation;
1450}
1451
1452static bool isModification(AccessKinds AK) {
1453 switch (AK) {
1454 case AK_Read:
1455 case AK_ReadObjectRepresentation:
1456 case AK_MemberCall:
1457 case AK_DynamicCast:
1458 case AK_TypeId:
1459 return false;
1460 case AK_Assign:
1461 case AK_Increment:
1462 case AK_Decrement:
1463 case AK_Construct:
1464 case AK_Destroy:
1465 return true;
1466 }
1467 llvm_unreachable("unknown access kind")::llvm::llvm_unreachable_internal("unknown access kind", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1467)
;
1468}
1469
1470static bool isAnyAccess(AccessKinds AK) {
1471 return isRead(AK) || isModification(AK);
1472}
1473
1474/// Is this an access per the C++ definition?
1475static bool isFormalAccess(AccessKinds AK) {
1476 return isAnyAccess(AK) && AK != AK_Construct && AK != AK_Destroy;
1477}
1478
1479/// Is this kind of axcess valid on an indeterminate object value?
1480static bool isValidIndeterminateAccess(AccessKinds AK) {
1481 switch (AK) {
1482 case AK_Read:
1483 case AK_Increment:
1484 case AK_Decrement:
1485 // These need the object's value.
1486 return false;
1487
1488 case AK_ReadObjectRepresentation:
1489 case AK_Assign:
1490 case AK_Construct:
1491 case AK_Destroy:
1492 // Construction and destruction don't need the value.
1493 return true;
1494
1495 case AK_MemberCall:
1496 case AK_DynamicCast:
1497 case AK_TypeId:
1498 // These aren't really meaningful on scalars.
1499 return true;
1500 }
1501 llvm_unreachable("unknown access kind")::llvm::llvm_unreachable_internal("unknown access kind", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1501)
;
1502}
1503
1504namespace {
1505 struct ComplexValue {
1506 private:
1507 bool IsInt;
1508
1509 public:
1510 APSInt IntReal, IntImag;
1511 APFloat FloatReal, FloatImag;
1512
1513 ComplexValue() : FloatReal(APFloat::Bogus()), FloatImag(APFloat::Bogus()) {}
1514
1515 void makeComplexFloat() { IsInt = false; }
1516 bool isComplexFloat() const { return !IsInt; }
1517 APFloat &getComplexFloatReal() { return FloatReal; }
1518 APFloat &getComplexFloatImag() { return FloatImag; }
1519
1520 void makeComplexInt() { IsInt = true; }
1521 bool isComplexInt() const { return IsInt; }
1522 APSInt &getComplexIntReal() { return IntReal; }
1523 APSInt &getComplexIntImag() { return IntImag; }
1524
1525 void moveInto(APValue &v) const {
1526 if (isComplexFloat())
1527 v = APValue(FloatReal, FloatImag);
1528 else
1529 v = APValue(IntReal, IntImag);
1530 }
1531 void setFrom(const APValue &v) {
1532 assert(v.isComplexFloat() || v.isComplexInt())(static_cast <bool> (v.isComplexFloat() || v.isComplexInt
()) ? void (0) : __assert_fail ("v.isComplexFloat() || v.isComplexInt()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1532, __extension__ __PRETTY_FUNCTION__))
;
1533 if (v.isComplexFloat()) {
1534 makeComplexFloat();
1535 FloatReal = v.getComplexFloatReal();
1536 FloatImag = v.getComplexFloatImag();
1537 } else {
1538 makeComplexInt();
1539 IntReal = v.getComplexIntReal();
1540 IntImag = v.getComplexIntImag();
1541 }
1542 }
1543 };
1544
1545 struct LValue {
1546 APValue::LValueBase Base;
1547 CharUnits Offset;
1548 SubobjectDesignator Designator;
1549 bool IsNullPtr : 1;
1550 bool InvalidBase : 1;
1551
1552 const APValue::LValueBase getLValueBase() const { return Base; }
1553 CharUnits &getLValueOffset() { return Offset; }
1554 const CharUnits &getLValueOffset() const { return Offset; }
1555 SubobjectDesignator &getLValueDesignator() { return Designator; }
1556 const SubobjectDesignator &getLValueDesignator() const { return Designator;}
1557 bool isNullPointer() const { return IsNullPtr;}
1558
1559 unsigned getLValueCallIndex() const { return Base.getCallIndex(); }
1560 unsigned getLValueVersion() const { return Base.getVersion(); }
1561
1562 void moveInto(APValue &V) const {
1563 if (Designator.Invalid)
1564 V = APValue(Base, Offset, APValue::NoLValuePath(), IsNullPtr);
1565 else {
1566 assert(!InvalidBase && "APValues can't handle invalid LValue bases")(static_cast <bool> (!InvalidBase && "APValues can't handle invalid LValue bases"
) ? void (0) : __assert_fail ("!InvalidBase && \"APValues can't handle invalid LValue bases\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1566, __extension__ __PRETTY_FUNCTION__))
;
1567 V = APValue(Base, Offset, Designator.Entries,
1568 Designator.IsOnePastTheEnd, IsNullPtr);
1569 }
1570 }
1571 void setFrom(ASTContext &Ctx, const APValue &V) {
1572 assert(V.isLValue() && "Setting LValue from a non-LValue?")(static_cast <bool> (V.isLValue() && "Setting LValue from a non-LValue?"
) ? void (0) : __assert_fail ("V.isLValue() && \"Setting LValue from a non-LValue?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1572, __extension__ __PRETTY_FUNCTION__))
;
1573 Base = V.getLValueBase();
1574 Offset = V.getLValueOffset();
1575 InvalidBase = false;
1576 Designator = SubobjectDesignator(Ctx, V);
1577 IsNullPtr = V.isNullPointer();
1578 }
1579
1580 void set(APValue::LValueBase B, bool BInvalid = false) {
1581#ifndef NDEBUG
1582 // We only allow a few types of invalid bases. Enforce that here.
1583 if (BInvalid) {
1584 const auto *E = B.get<const Expr *>();
1585 assert((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) &&(static_cast <bool> ((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall
(E)) && "Unexpected type of invalid base") ? void (0)
: __assert_fail ("(isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) && \"Unexpected type of invalid base\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1586, __extension__ __PRETTY_FUNCTION__))
1586 "Unexpected type of invalid base")(static_cast <bool> ((isa<MemberExpr>(E) || tryUnwrapAllocSizeCall
(E)) && "Unexpected type of invalid base") ? void (0)
: __assert_fail ("(isa<MemberExpr>(E) || tryUnwrapAllocSizeCall(E)) && \"Unexpected type of invalid base\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1586, __extension__ __PRETTY_FUNCTION__))
;
1587 }
1588#endif
1589
1590 Base = B;
1591 Offset = CharUnits::fromQuantity(0);
1592 InvalidBase = BInvalid;
1593 Designator = SubobjectDesignator(getType(B));
1594 IsNullPtr = false;
1595 }
1596
1597 void setNull(ASTContext &Ctx, QualType PointerTy) {
1598 Base = (const ValueDecl *)nullptr;
1599 Offset =
1600 CharUnits::fromQuantity(Ctx.getTargetNullPointerValue(PointerTy));
1601 InvalidBase = false;
1602 Designator = SubobjectDesignator(PointerTy->getPointeeType());
1603 IsNullPtr = true;
1604 }
1605
1606 void setInvalid(APValue::LValueBase B, unsigned I = 0) {
1607 set(B, true);
1608 }
1609
1610 std::string toString(ASTContext &Ctx, QualType T) const {
1611 APValue Printable;
1612 moveInto(Printable);
1613 return Printable.getAsString(Ctx, T);
1614 }
1615
1616 private:
1617 // Check that this LValue is not based on a null pointer. If it is, produce
1618 // a diagnostic and mark the designator as invalid.
1619 template <typename GenDiagType>
1620 bool checkNullPointerDiagnosingWith(const GenDiagType &GenDiag) {
1621 if (Designator.Invalid)
1622 return false;
1623 if (IsNullPtr) {
1624 GenDiag();
1625 Designator.setInvalid();
1626 return false;
1627 }
1628 return true;
1629 }
1630
1631 public:
1632 bool checkNullPointer(EvalInfo &Info, const Expr *E,
1633 CheckSubobjectKind CSK) {
1634 return checkNullPointerDiagnosingWith([&Info, E, CSK] {
1635 Info.CCEDiag(E, diag::note_constexpr_null_subobject) << CSK;
1636 });
1637 }
1638
1639 bool checkNullPointerForFoldAccess(EvalInfo &Info, const Expr *E,
1640 AccessKinds AK) {
1641 return checkNullPointerDiagnosingWith([&Info, E, AK] {
1642 Info.FFDiag(E, diag::note_constexpr_access_null) << AK;
1643 });
1644 }
1645
1646 // Check this LValue refers to an object. If not, set the designator to be
1647 // invalid and emit a diagnostic.
1648 bool checkSubobject(EvalInfo &Info, const Expr *E, CheckSubobjectKind CSK) {
1649 return (CSK == CSK_ArrayToPointer || checkNullPointer(Info, E, CSK)) &&
1650 Designator.checkSubobject(Info, E, CSK);
1651 }
1652
1653 void addDecl(EvalInfo &Info, const Expr *E,
1654 const Decl *D, bool Virtual = false) {
1655 if (checkSubobject(Info, E, isa<FieldDecl>(D) ? CSK_Field : CSK_Base))
1656 Designator.addDeclUnchecked(D, Virtual);
1657 }
1658 void addUnsizedArray(EvalInfo &Info, const Expr *E, QualType ElemTy) {
1659 if (!Designator.Entries.empty()) {
1660 Info.CCEDiag(E, diag::note_constexpr_unsupported_unsized_array);
1661 Designator.setInvalid();
1662 return;
1663 }
1664 if (checkSubobject(Info, E, CSK_ArrayToPointer)) {
1665 assert(getType(Base)->isPointerType() || getType(Base)->isArrayType())(static_cast <bool> (getType(Base)->isPointerType() ||
getType(Base)->isArrayType()) ? void (0) : __assert_fail (
"getType(Base)->isPointerType() || getType(Base)->isArrayType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1665, __extension__ __PRETTY_FUNCTION__))
;
1666 Designator.FirstEntryIsAnUnsizedArray = true;
1667 Designator.addUnsizedArrayUnchecked(ElemTy);
1668 }
1669 }
1670 void addArray(EvalInfo &Info, const Expr *E, const ConstantArrayType *CAT) {
1671 if (checkSubobject(Info, E, CSK_ArrayToPointer))
1672 Designator.addArrayUnchecked(CAT);
1673 }
1674 void addComplex(EvalInfo &Info, const Expr *E, QualType EltTy, bool Imag) {
1675 if (checkSubobject(Info, E, Imag ? CSK_Imag : CSK_Real))
1676 Designator.addComplexUnchecked(EltTy, Imag);
1677 }
1678 void clearIsNullPointer() {
1679 IsNullPtr = false;
1680 }
1681 void adjustOffsetAndIndex(EvalInfo &Info, const Expr *E,
1682 const APSInt &Index, CharUnits ElementSize) {
1683 // An index of 0 has no effect. (In C, adding 0 to a null pointer is UB,
1684 // but we're not required to diagnose it and it's valid in C++.)
1685 if (!Index)
1686 return;
1687
1688 // Compute the new offset in the appropriate width, wrapping at 64 bits.
1689 // FIXME: When compiling for a 32-bit target, we should use 32-bit
1690 // offsets.
1691 uint64_t Offset64 = Offset.getQuantity();
1692 uint64_t ElemSize64 = ElementSize.getQuantity();
1693 uint64_t Index64 = Index.extOrTrunc(64).getZExtValue();
1694 Offset = CharUnits::fromQuantity(Offset64 + ElemSize64 * Index64);
1695
1696 if (checkNullPointer(Info, E, CSK_ArrayIndex))
1697 Designator.adjustIndex(Info, E, Index);
1698 clearIsNullPointer();
1699 }
1700 void adjustOffset(CharUnits N) {
1701 Offset += N;
1702 if (N.getQuantity())
1703 clearIsNullPointer();
1704 }
1705 };
1706
1707 struct MemberPtr {
1708 MemberPtr() {}
1709 explicit MemberPtr(const ValueDecl *Decl) :
1710 DeclAndIsDerivedMember(Decl, false), Path() {}
1711
1712 /// The member or (direct or indirect) field referred to by this member
1713 /// pointer, or 0 if this is a null member pointer.
1714 const ValueDecl *getDecl() const {
1715 return DeclAndIsDerivedMember.getPointer();
1716 }
1717 /// Is this actually a member of some type derived from the relevant class?
1718 bool isDerivedMember() const {
1719 return DeclAndIsDerivedMember.getInt();
1720 }
1721 /// Get the class which the declaration actually lives in.
1722 const CXXRecordDecl *getContainingRecord() const {
1723 return cast<CXXRecordDecl>(
1724 DeclAndIsDerivedMember.getPointer()->getDeclContext());
1725 }
1726
1727 void moveInto(APValue &V) const {
1728 V = APValue(getDecl(), isDerivedMember(), Path);
1729 }
1730 void setFrom(const APValue &V) {
1731 assert(V.isMemberPointer())(static_cast <bool> (V.isMemberPointer()) ? void (0) : __assert_fail
("V.isMemberPointer()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1731, __extension__ __PRETTY_FUNCTION__))
;
1732 DeclAndIsDerivedMember.setPointer(V.getMemberPointerDecl());
1733 DeclAndIsDerivedMember.setInt(V.isMemberPointerToDerivedMember());
1734 Path.clear();
1735 ArrayRef<const CXXRecordDecl*> P = V.getMemberPointerPath();
1736 Path.insert(Path.end(), P.begin(), P.end());
1737 }
1738
1739 /// DeclAndIsDerivedMember - The member declaration, and a flag indicating
1740 /// whether the member is a member of some class derived from the class type
1741 /// of the member pointer.
1742 llvm::PointerIntPair<const ValueDecl*, 1, bool> DeclAndIsDerivedMember;
1743 /// Path - The path of base/derived classes from the member declaration's
1744 /// class (exclusive) to the class type of the member pointer (inclusive).
1745 SmallVector<const CXXRecordDecl*, 4> Path;
1746
1747 /// Perform a cast towards the class of the Decl (either up or down the
1748 /// hierarchy).
1749 bool castBack(const CXXRecordDecl *Class) {
1750 assert(!Path.empty())(static_cast <bool> (!Path.empty()) ? void (0) : __assert_fail
("!Path.empty()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1750, __extension__ __PRETTY_FUNCTION__))
;
1751 const CXXRecordDecl *Expected;
1752 if (Path.size() >= 2)
1753 Expected = Path[Path.size() - 2];
1754 else
1755 Expected = getContainingRecord();
1756 if (Expected->getCanonicalDecl() != Class->getCanonicalDecl()) {
1757 // C++11 [expr.static.cast]p12: In a conversion from (D::*) to (B::*),
1758 // if B does not contain the original member and is not a base or
1759 // derived class of the class containing the original member, the result
1760 // of the cast is undefined.
1761 // C++11 [conv.mem]p2 does not cover this case for a cast from (B::*) to
1762 // (D::*). We consider that to be a language defect.
1763 return false;
1764 }
1765 Path.pop_back();
1766 return true;
1767 }
1768 /// Perform a base-to-derived member pointer cast.
1769 bool castToDerived(const CXXRecordDecl *Derived) {
1770 if (!getDecl())
1771 return true;
1772 if (!isDerivedMember()) {
1773 Path.push_back(Derived);
1774 return true;
1775 }
1776 if (!castBack(Derived))
1777 return false;
1778 if (Path.empty())
1779 DeclAndIsDerivedMember.setInt(false);
1780 return true;
1781 }
1782 /// Perform a derived-to-base member pointer cast.
1783 bool castToBase(const CXXRecordDecl *Base) {
1784 if (!getDecl())
1785 return true;
1786 if (Path.empty())
1787 DeclAndIsDerivedMember.setInt(true);
1788 if (isDerivedMember()) {
1789 Path.push_back(Base);
1790 return true;
1791 }
1792 return castBack(Base);
1793 }
1794 };
1795
1796 /// Compare two member pointers, which are assumed to be of the same type.
1797 static bool operator==(const MemberPtr &LHS, const MemberPtr &RHS) {
1798 if (!LHS.getDecl() || !RHS.getDecl())
1799 return !LHS.getDecl() && !RHS.getDecl();
1800 if (LHS.getDecl()->getCanonicalDecl() != RHS.getDecl()->getCanonicalDecl())
1801 return false;
1802 return LHS.Path == RHS.Path;
1803 }
1804}
1805
1806static bool Evaluate(APValue &Result, EvalInfo &Info, const Expr *E);
1807static bool EvaluateInPlace(APValue &Result, EvalInfo &Info,
1808 const LValue &This, const Expr *E,
1809 bool AllowNonLiteralTypes = false);
1810static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info,
1811 bool InvalidBaseOK = false);
1812static bool EvaluatePointer(const Expr *E, LValue &Result, EvalInfo &Info,
1813 bool InvalidBaseOK = false);
1814static bool EvaluateMemberPointer(const Expr *E, MemberPtr &Result,
1815 EvalInfo &Info);
1816static bool EvaluateTemporary(const Expr *E, LValue &Result, EvalInfo &Info);
1817static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info);
1818static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result,
1819 EvalInfo &Info);
1820static bool EvaluateFloat(const Expr *E, APFloat &Result, EvalInfo &Info);
1821static bool EvaluateComplex(const Expr *E, ComplexValue &Res, EvalInfo &Info);
1822static bool EvaluateAtomic(const Expr *E, const LValue *This, APValue &Result,
1823 EvalInfo &Info);
1824static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result);
1825static bool EvaluateBuiltinStrLen(const Expr *E, uint64_t &Result,
1826 EvalInfo &Info);
1827
1828/// Evaluate an integer or fixed point expression into an APResult.
1829static bool EvaluateFixedPointOrInteger(const Expr *E, APFixedPoint &Result,
1830 EvalInfo &Info);
1831
1832/// Evaluate only a fixed point expression into an APResult.
1833static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result,
1834 EvalInfo &Info);
1835
1836//===----------------------------------------------------------------------===//
1837// Misc utilities
1838//===----------------------------------------------------------------------===//
1839
1840/// Negate an APSInt in place, converting it to a signed form if necessary, and
1841/// preserving its value (by extending by up to one bit as needed).
1842static void negateAsSigned(APSInt &Int) {
1843 if (Int.isUnsigned() || Int.isMinSignedValue()) {
1844 Int = Int.extend(Int.getBitWidth() + 1);
1845 Int.setIsSigned(true);
1846 }
1847 Int = -Int;
1848}
1849
1850template<typename KeyT>
1851APValue &CallStackFrame::createTemporary(const KeyT *Key, QualType T,
1852 ScopeKind Scope, LValue &LV) {
1853 unsigned Version = getTempVersion();
1854 APValue::LValueBase Base(Key, Index, Version);
1855 LV.set(Base);
1856 return createLocal(Base, Key, T, Scope);
1857}
1858
1859/// Allocate storage for a parameter of a function call made in this frame.
1860APValue &CallStackFrame::createParam(CallRef Args, const ParmVarDecl *PVD,
1861 LValue &LV) {
1862 assert(Args.CallIndex == Index && "creating parameter in wrong frame")(static_cast <bool> (Args.CallIndex == Index &&
"creating parameter in wrong frame") ? void (0) : __assert_fail
("Args.CallIndex == Index && \"creating parameter in wrong frame\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1862, __extension__ __PRETTY_FUNCTION__))
;
1863 APValue::LValueBase Base(PVD, Index, Args.Version);
1864 LV.set(Base);
1865 // We always destroy parameters at the end of the call, even if we'd allow
1866 // them to live to the end of the full-expression at runtime, in order to
1867 // give portable results and match other compilers.
1868 return createLocal(Base, PVD, PVD->getType(), ScopeKind::Call);
1869}
1870
1871APValue &CallStackFrame::createLocal(APValue::LValueBase Base, const void *Key,
1872 QualType T, ScopeKind Scope) {
1873 assert(Base.getCallIndex() == Index && "lvalue for wrong frame")(static_cast <bool> (Base.getCallIndex() == Index &&
"lvalue for wrong frame") ? void (0) : __assert_fail ("Base.getCallIndex() == Index && \"lvalue for wrong frame\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1873, __extension__ __PRETTY_FUNCTION__))
;
1874 unsigned Version = Base.getVersion();
1875 APValue &Result = Temporaries[MapKeyTy(Key, Version)];
1876 assert(Result.isAbsent() && "local created multiple times")(static_cast <bool> (Result.isAbsent() && "local created multiple times"
) ? void (0) : __assert_fail ("Result.isAbsent() && \"local created multiple times\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1876, __extension__ __PRETTY_FUNCTION__))
;
1877
1878 // If we're creating a local immediately in the operand of a speculative
1879 // evaluation, don't register a cleanup to be run outside the speculative
1880 // evaluation context, since we won't actually be able to initialize this
1881 // object.
1882 if (Index <= Info.SpeculativeEvaluationDepth) {
1883 if (T.isDestructedType())
1884 Info.noteSideEffect();
1885 } else {
1886 Info.CleanupStack.push_back(Cleanup(&Result, Base, T, Scope));
1887 }
1888 return Result;
1889}
1890
1891APValue *EvalInfo::createHeapAlloc(const Expr *E, QualType T, LValue &LV) {
1892 if (NumHeapAllocs > DynamicAllocLValue::getMaxIndex()) {
1893 FFDiag(E, diag::note_constexpr_heap_alloc_limit_exceeded);
1894 return nullptr;
1895 }
1896
1897 DynamicAllocLValue DA(NumHeapAllocs++);
1898 LV.set(APValue::LValueBase::getDynamicAlloc(DA, T));
1899 auto Result = HeapAllocs.emplace(std::piecewise_construct,
1900 std::forward_as_tuple(DA), std::tuple<>());
1901 assert(Result.second && "reused a heap alloc index?")(static_cast <bool> (Result.second && "reused a heap alloc index?"
) ? void (0) : __assert_fail ("Result.second && \"reused a heap alloc index?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1901, __extension__ __PRETTY_FUNCTION__))
;
1902 Result.first->second.AllocExpr = E;
1903 return &Result.first->second.Value;
1904}
1905
1906/// Produce a string describing the given constexpr call.
1907void CallStackFrame::describe(raw_ostream &Out) {
1908 unsigned ArgIndex = 0;
1909 bool IsMemberCall = isa<CXXMethodDecl>(Callee) &&
1910 !isa<CXXConstructorDecl>(Callee) &&
1911 cast<CXXMethodDecl>(Callee)->isInstance();
1912
1913 if (!IsMemberCall)
1914 Out << *Callee << '(';
1915
1916 if (This && IsMemberCall) {
1917 APValue Val;
1918 This->moveInto(Val);
1919 Val.printPretty(Out, Info.Ctx,
1920 This->Designator.MostDerivedType);
1921 // FIXME: Add parens around Val if needed.
1922 Out << "->" << *Callee << '(';
1923 IsMemberCall = false;
1924 }
1925
1926 for (FunctionDecl::param_const_iterator I = Callee->param_begin(),
1927 E = Callee->param_end(); I != E; ++I, ++ArgIndex) {
1928 if (ArgIndex > (unsigned)IsMemberCall)
1929 Out << ", ";
1930
1931 const ParmVarDecl *Param = *I;
1932 APValue *V = Info.getParamSlot(Arguments, Param);
1933 if (V)
1934 V->printPretty(Out, Info.Ctx, Param->getType());
1935 else
1936 Out << "<...>";
1937
1938 if (ArgIndex == 0 && IsMemberCall)
1939 Out << "->" << *Callee << '(';
1940 }
1941
1942 Out << ')';
1943}
1944
1945/// Evaluate an expression to see if it had side-effects, and discard its
1946/// result.
1947/// \return \c true if the caller should keep evaluating.
1948static bool EvaluateIgnoredValue(EvalInfo &Info, const Expr *E) {
1949 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 1949, __extension__ __PRETTY_FUNCTION__))
;
1950 APValue Scratch;
1951 if (!Evaluate(Scratch, Info, E))
1952 // We don't need the value, but we might have skipped a side effect here.
1953 return Info.noteSideEffect();
1954 return true;
1955}
1956
1957/// Should this call expression be treated as a string literal?
1958static bool IsStringLiteralCall(const CallExpr *E) {
1959 unsigned Builtin = E->getBuiltinCallee();
1960 return (Builtin == Builtin::BI__builtin___CFStringMakeConstantString ||
1961 Builtin == Builtin::BI__builtin___NSStringMakeConstantString);
1962}
1963
1964static bool IsGlobalLValue(APValue::LValueBase B) {
1965 // C++11 [expr.const]p3 An address constant expression is a prvalue core
1966 // constant expression of pointer type that evaluates to...
1967
1968 // ... a null pointer value, or a prvalue core constant expression of type
1969 // std::nullptr_t.
1970 if (!B) return true;
1971
1972 if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) {
1973 // ... the address of an object with static storage duration,
1974 if (const VarDecl *VD = dyn_cast<VarDecl>(D))
1975 return VD->hasGlobalStorage();
1976 if (isa<TemplateParamObjectDecl>(D))
1977 return true;
1978 // ... the address of a function,
1979 // ... the address of a GUID [MS extension],
1980 return isa<FunctionDecl>(D) || isa<MSGuidDecl>(D);
1981 }
1982
1983 if (B.is<TypeInfoLValue>() || B.is<DynamicAllocLValue>())
1984 return true;
1985
1986 const Expr *E = B.get<const Expr*>();
1987 switch (E->getStmtClass()) {
1988 default:
1989 return false;
1990 case Expr::CompoundLiteralExprClass: {
1991 const CompoundLiteralExpr *CLE = cast<CompoundLiteralExpr>(E);
1992 return CLE->isFileScope() && CLE->isLValue();
1993 }
1994 case Expr::MaterializeTemporaryExprClass:
1995 // A materialized temporary might have been lifetime-extended to static
1996 // storage duration.
1997 return cast<MaterializeTemporaryExpr>(E)->getStorageDuration() == SD_Static;
1998 // A string literal has static storage duration.
1999 case Expr::StringLiteralClass:
2000 case Expr::PredefinedExprClass:
2001 case Expr::ObjCStringLiteralClass:
2002 case Expr::ObjCEncodeExprClass:
2003 return true;
2004 case Expr::ObjCBoxedExprClass:
2005 return cast<ObjCBoxedExpr>(E)->isExpressibleAsConstantInitializer();
2006 case Expr::CallExprClass:
2007 return IsStringLiteralCall(cast<CallExpr>(E));
2008 // For GCC compatibility, &&label has static storage duration.
2009 case Expr::AddrLabelExprClass:
2010 return true;
2011 // A Block literal expression may be used as the initialization value for
2012 // Block variables at global or local static scope.
2013 case Expr::BlockExprClass:
2014 return !cast<BlockExpr>(E)->getBlockDecl()->hasCaptures();
2015 case Expr::ImplicitValueInitExprClass:
2016 // FIXME:
2017 // We can never form an lvalue with an implicit value initialization as its
2018 // base through expression evaluation, so these only appear in one case: the
2019 // implicit variable declaration we invent when checking whether a constexpr
2020 // constructor can produce a constant expression. We must assume that such
2021 // an expression might be a global lvalue.
2022 return true;
2023 }
2024}
2025
2026static const ValueDecl *GetLValueBaseDecl(const LValue &LVal) {
2027 return LVal.Base.dyn_cast<const ValueDecl*>();
2028}
2029
2030static bool IsLiteralLValue(const LValue &Value) {
2031 if (Value.getLValueCallIndex())
2032 return false;
2033 const Expr *E = Value.Base.dyn_cast<const Expr*>();
2034 return E && !isa<MaterializeTemporaryExpr>(E);
2035}
2036
2037static bool IsWeakLValue(const LValue &Value) {
2038 const ValueDecl *Decl = GetLValueBaseDecl(Value);
2039 return Decl && Decl->isWeak();
2040}
2041
2042static bool isZeroSized(const LValue &Value) {
2043 const ValueDecl *Decl = GetLValueBaseDecl(Value);
2044 if (Decl && isa<VarDecl>(Decl)) {
2045 QualType Ty = Decl->getType();
2046 if (Ty->isArrayType())
2047 return Ty->isIncompleteType() ||
2048 Decl->getASTContext().getTypeSize(Ty) == 0;
2049 }
2050 return false;
2051}
2052
2053static bool HasSameBase(const LValue &A, const LValue &B) {
2054 if (!A.getLValueBase())
2055 return !B.getLValueBase();
2056 if (!B.getLValueBase())
2057 return false;
2058
2059 if (A.getLValueBase().getOpaqueValue() !=
2060 B.getLValueBase().getOpaqueValue())
2061 return false;
2062
2063 return A.getLValueCallIndex() == B.getLValueCallIndex() &&
2064 A.getLValueVersion() == B.getLValueVersion();
2065}
2066
2067static void NoteLValueLocation(EvalInfo &Info, APValue::LValueBase Base) {
2068 assert(Base && "no location for a null lvalue")(static_cast <bool> (Base && "no location for a null lvalue"
) ? void (0) : __assert_fail ("Base && \"no location for a null lvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2068, __extension__ __PRETTY_FUNCTION__))
;
2069 const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>();
2070
2071 // For a parameter, find the corresponding call stack frame (if it still
2072 // exists), and point at the parameter of the function definition we actually
2073 // invoked.
2074 if (auto *PVD = dyn_cast_or_null<ParmVarDecl>(VD)) {
2075 unsigned Idx = PVD->getFunctionScopeIndex();
2076 for (CallStackFrame *F = Info.CurrentCall; F; F = F->Caller) {
2077 if (F->Arguments.CallIndex == Base.getCallIndex() &&
2078 F->Arguments.Version == Base.getVersion() && F->Callee &&
2079 Idx < F->Callee->getNumParams()) {
2080 VD = F->Callee->getParamDecl(Idx);
2081 break;
2082 }
2083 }
2084 }
2085
2086 if (VD)
2087 Info.Note(VD->getLocation(), diag::note_declared_at);
2088 else if (const Expr *E = Base.dyn_cast<const Expr*>())
2089 Info.Note(E->getExprLoc(), diag::note_constexpr_temporary_here);
2090 else if (DynamicAllocLValue DA = Base.dyn_cast<DynamicAllocLValue>()) {
2091 // FIXME: Produce a note for dangling pointers too.
2092 if (Optional<DynAlloc*> Alloc = Info.lookupDynamicAlloc(DA))
2093 Info.Note((*Alloc)->AllocExpr->getExprLoc(),
2094 diag::note_constexpr_dynamic_alloc_here);
2095 }
2096 // We have no information to show for a typeid(T) object.
2097}
2098
2099enum class CheckEvaluationResultKind {
2100 ConstantExpression,
2101 FullyInitialized,
2102};
2103
2104/// Materialized temporaries that we've already checked to determine if they're
2105/// initializsed by a constant expression.
2106using CheckedTemporaries =
2107 llvm::SmallPtrSet<const MaterializeTemporaryExpr *, 8>;
2108
2109static bool CheckEvaluationResult(CheckEvaluationResultKind CERK,
2110 EvalInfo &Info, SourceLocation DiagLoc,
2111 QualType Type, const APValue &Value,
2112 ConstantExprKind Kind,
2113 SourceLocation SubobjectLoc,
2114 CheckedTemporaries &CheckedTemps);
2115
2116/// Check that this reference or pointer core constant expression is a valid
2117/// value for an address or reference constant expression. Return true if we
2118/// can fold this expression, whether or not it's a constant expression.
2119static bool CheckLValueConstantExpression(EvalInfo &Info, SourceLocation Loc,
2120 QualType Type, const LValue &LVal,
2121 ConstantExprKind Kind,
2122 CheckedTemporaries &CheckedTemps) {
2123 bool IsReferenceType = Type->isReferenceType();
2124
2125 APValue::LValueBase Base = LVal.getLValueBase();
2126 const SubobjectDesignator &Designator = LVal.getLValueDesignator();
2127
2128 const Expr *BaseE = Base.dyn_cast<const Expr *>();
2129 const ValueDecl *BaseVD = Base.dyn_cast<const ValueDecl*>();
2130
2131 // Additional restrictions apply in a template argument. We only enforce the
2132 // C++20 restrictions here; additional syntactic and semantic restrictions
2133 // are applied elsewhere.
2134 if (isTemplateArgument(Kind)) {
2135 int InvalidBaseKind = -1;
2136 StringRef Ident;
2137 if (Base.is<TypeInfoLValue>())
2138 InvalidBaseKind = 0;
2139 else if (isa_and_nonnull<StringLiteral>(BaseE))
2140 InvalidBaseKind = 1;
2141 else if (isa_and_nonnull<MaterializeTemporaryExpr>(BaseE) ||
2142 isa_and_nonnull<LifetimeExtendedTemporaryDecl>(BaseVD))
2143 InvalidBaseKind = 2;
2144 else if (auto *PE = dyn_cast_or_null<PredefinedExpr>(BaseE)) {
2145 InvalidBaseKind = 3;
2146 Ident = PE->getIdentKindName();
2147 }
2148
2149 if (InvalidBaseKind != -1) {
2150 Info.FFDiag(Loc, diag::note_constexpr_invalid_template_arg)
2151 << IsReferenceType << !Designator.Entries.empty() << InvalidBaseKind
2152 << Ident;
2153 return false;
2154 }
2155 }
2156
2157 if (auto *FD = dyn_cast_or_null<FunctionDecl>(BaseVD)) {
2158 if (FD->isConsteval()) {
2159 Info.FFDiag(Loc, diag::note_consteval_address_accessible)
2160 << !Type->isAnyPointerType();
2161 Info.Note(FD->getLocation(), diag::note_declared_at);
2162 return false;
2163 }
2164 }
2165
2166 // Check that the object is a global. Note that the fake 'this' object we
2167 // manufacture when checking potential constant expressions is conservatively
2168 // assumed to be global here.
2169 if (!IsGlobalLValue(Base)) {
2170 if (Info.getLangOpts().CPlusPlus11) {
2171 const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>();
2172 Info.FFDiag(Loc, diag::note_constexpr_non_global, 1)
2173 << IsReferenceType << !Designator.Entries.empty()
2174 << !!VD << VD;
2175
2176 auto *VarD = dyn_cast_or_null<VarDecl>(VD);
2177 if (VarD && VarD->isConstexpr()) {
2178 // Non-static local constexpr variables have unintuitive semantics:
2179 // constexpr int a = 1;
2180 // constexpr const int *p = &a;
2181 // ... is invalid because the address of 'a' is not constant. Suggest
2182 // adding a 'static' in this case.
2183 Info.Note(VarD->getLocation(), diag::note_constexpr_not_static)
2184 << VarD
2185 << FixItHint::CreateInsertion(VarD->getBeginLoc(), "static ");
2186 } else {
2187 NoteLValueLocation(Info, Base);
2188 }
2189 } else {
2190 Info.FFDiag(Loc);
2191 }
2192 // Don't allow references to temporaries to escape.
2193 return false;
2194 }
2195 assert((Info.checkingPotentialConstantExpression() ||(static_cast <bool> ((Info.checkingPotentialConstantExpression
() || LVal.getLValueCallIndex() == 0) && "have call index for global lvalue"
) ? void (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2197, __extension__ __PRETTY_FUNCTION__))
2196 LVal.getLValueCallIndex() == 0) &&(static_cast <bool> ((Info.checkingPotentialConstantExpression
() || LVal.getLValueCallIndex() == 0) && "have call index for global lvalue"
) ? void (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2197, __extension__ __PRETTY_FUNCTION__))
2197 "have call index for global lvalue")(static_cast <bool> ((Info.checkingPotentialConstantExpression
() || LVal.getLValueCallIndex() == 0) && "have call index for global lvalue"
) ? void (0) : __assert_fail ("(Info.checkingPotentialConstantExpression() || LVal.getLValueCallIndex() == 0) && \"have call index for global lvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2197, __extension__ __PRETTY_FUNCTION__))
;
2198
2199 if (Base.is<DynamicAllocLValue>()) {
2200 Info.FFDiag(Loc, diag::note_constexpr_dynamic_alloc)
2201 << IsReferenceType << !Designator.Entries.empty();
2202 NoteLValueLocation(Info, Base);
2203 return false;
2204 }
2205
2206 if (BaseVD) {
2207 if (const VarDecl *Var = dyn_cast<const VarDecl>(BaseVD)) {
2208 // Check if this is a thread-local variable.
2209 if (Var->getTLSKind())
2210 // FIXME: Diagnostic!
2211 return false;
2212
2213 // A dllimport variable never acts like a constant, unless we're
2214 // evaluating a value for use only in name mangling.
2215 if (!isForManglingOnly(Kind) && Var->hasAttr<DLLImportAttr>())
2216 // FIXME: Diagnostic!
2217 return false;
2218 }
2219 if (const auto *FD = dyn_cast<const FunctionDecl>(BaseVD)) {
2220 // __declspec(dllimport) must be handled very carefully:
2221 // We must never initialize an expression with the thunk in C++.
2222 // Doing otherwise would allow the same id-expression to yield
2223 // different addresses for the same function in different translation
2224 // units. However, this means that we must dynamically initialize the
2225 // expression with the contents of the import address table at runtime.
2226 //
2227 // The C language has no notion of ODR; furthermore, it has no notion of
2228 // dynamic initialization. This means that we are permitted to
2229 // perform initialization with the address of the thunk.
2230 if (Info.getLangOpts().CPlusPlus && !isForManglingOnly(Kind) &&
2231 FD->hasAttr<DLLImportAttr>())
2232 // FIXME: Diagnostic!
2233 return false;
2234 }
2235 } else if (const auto *MTE =
2236 dyn_cast_or_null<MaterializeTemporaryExpr>(BaseE)) {
2237 if (CheckedTemps.insert(MTE).second) {
2238 QualType TempType = getType(Base);
2239 if (TempType.isDestructedType()) {
2240 Info.FFDiag(MTE->getExprLoc(),
2241 diag::note_constexpr_unsupported_temporary_nontrivial_dtor)
2242 << TempType;
2243 return false;
2244 }
2245
2246 APValue *V = MTE->getOrCreateValue(false);
2247 assert(V && "evasluation result refers to uninitialised temporary")(static_cast <bool> (V && "evasluation result refers to uninitialised temporary"
) ? void (0) : __assert_fail ("V && \"evasluation result refers to uninitialised temporary\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2247, __extension__ __PRETTY_FUNCTION__))
;
2248 if (!CheckEvaluationResult(CheckEvaluationResultKind::ConstantExpression,
2249 Info, MTE->getExprLoc(), TempType, *V,
2250 Kind, SourceLocation(), CheckedTemps))
2251 return false;
2252 }
2253 }
2254
2255 // Allow address constant expressions to be past-the-end pointers. This is
2256 // an extension: the standard requires them to point to an object.
2257 if (!IsReferenceType)
2258 return true;
2259
2260 // A reference constant expression must refer to an object.
2261 if (!Base) {
2262 // FIXME: diagnostic
2263 Info.CCEDiag(Loc);
2264 return true;
2265 }
2266
2267 // Does this refer one past the end of some object?
2268 if (!Designator.Invalid && Designator.isOnePastTheEnd()) {
2269 Info.FFDiag(Loc, diag::note_constexpr_past_end, 1)
2270 << !Designator.Entries.empty() << !!BaseVD << BaseVD;
2271 NoteLValueLocation(Info, Base);
2272 }
2273
2274 return true;
2275}
2276
2277/// Member pointers are constant expressions unless they point to a
2278/// non-virtual dllimport member function.
2279static bool CheckMemberPointerConstantExpression(EvalInfo &Info,
2280 SourceLocation Loc,
2281 QualType Type,
2282 const APValue &Value,
2283 ConstantExprKind Kind) {
2284 const ValueDecl *Member = Value.getMemberPointerDecl();
2285 const auto *FD = dyn_cast_or_null<CXXMethodDecl>(Member);
2286 if (!FD)
2287 return true;
2288 if (FD->isConsteval()) {
2289 Info.FFDiag(Loc, diag::note_consteval_address_accessible) << /*pointer*/ 0;
2290 Info.Note(FD->getLocation(), diag::note_declared_at);
2291 return false;
2292 }
2293 return isForManglingOnly(Kind) || FD->isVirtual() ||
2294 !FD->hasAttr<DLLImportAttr>();
2295}
2296
2297/// Check that this core constant expression is of literal type, and if not,
2298/// produce an appropriate diagnostic.
2299static bool CheckLiteralType(EvalInfo &Info, const Expr *E,
2300 const LValue *This = nullptr) {
2301 if (!E->isPRValue() || E->getType()->isLiteralType(Info.Ctx))
2302 return true;
2303
2304 // C++1y: A constant initializer for an object o [...] may also invoke
2305 // constexpr constructors for o and its subobjects even if those objects
2306 // are of non-literal class types.
2307 //
2308 // C++11 missed this detail for aggregates, so classes like this:
2309 // struct foo_t { union { int i; volatile int j; } u; };
2310 // are not (obviously) initializable like so:
2311 // __attribute__((__require_constant_initialization__))
2312 // static const foo_t x = {{0}};
2313 // because "i" is a subobject with non-literal initialization (due to the
2314 // volatile member of the union). See:
2315 // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1677
2316 // Therefore, we use the C++1y behavior.
2317 if (This && Info.EvaluatingDecl == This->getLValueBase())
2318 return true;
2319
2320 // Prvalue constant expressions must be of literal types.
2321 if (Info.getLangOpts().CPlusPlus11)
2322 Info.FFDiag(E, diag::note_constexpr_nonliteral)
2323 << E->getType();
2324 else
2325 Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
2326 return false;
2327}
2328
2329static bool CheckEvaluationResult(CheckEvaluationResultKind CERK,
2330 EvalInfo &Info, SourceLocation DiagLoc,
2331 QualType Type, const APValue &Value,
2332 ConstantExprKind Kind,
2333 SourceLocation SubobjectLoc,
2334 CheckedTemporaries &CheckedTemps) {
2335 if (!Value.hasValue()) {
2336 Info.FFDiag(DiagLoc, diag::note_constexpr_uninitialized)
2337 << true << Type;
2338 if (SubobjectLoc.isValid())
2339 Info.Note(SubobjectLoc, diag::note_constexpr_subobject_declared_here);
2340 return false;
2341 }
2342
2343 // We allow _Atomic(T) to be initialized from anything that T can be
2344 // initialized from.
2345 if (const AtomicType *AT = Type->getAs<AtomicType>())
2346 Type = AT->getValueType();
2347
2348 // Core issue 1454: For a literal constant expression of array or class type,
2349 // each subobject of its value shall have been initialized by a constant
2350 // expression.
2351 if (Value.isArray()) {
2352 QualType EltTy = Type->castAsArrayTypeUnsafe()->getElementType();
2353 for (unsigned I = 0, N = Value.getArrayInitializedElts(); I != N; ++I) {
2354 if (!CheckEvaluationResult(CERK, Info, DiagLoc, EltTy,
2355 Value.getArrayInitializedElt(I), Kind,
2356 SubobjectLoc, CheckedTemps))
2357 return false;
2358 }
2359 if (!Value.hasArrayFiller())
2360 return true;
2361 return CheckEvaluationResult(CERK, Info, DiagLoc, EltTy,
2362 Value.getArrayFiller(), Kind, SubobjectLoc,
2363 CheckedTemps);
2364 }
2365 if (Value.isUnion() && Value.getUnionField()) {
2366 return CheckEvaluationResult(
2367 CERK, Info, DiagLoc, Value.getUnionField()->getType(),
2368 Value.getUnionValue(), Kind, Value.getUnionField()->getLocation(),
2369 CheckedTemps);
2370 }
2371 if (Value.isStruct()) {
2372 RecordDecl *RD = Type->castAs<RecordType>()->getDecl();
2373 if (const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD)) {
2374 unsigned BaseIndex = 0;
2375 for (const CXXBaseSpecifier &BS : CD->bases()) {
2376 if (!CheckEvaluationResult(CERK, Info, DiagLoc, BS.getType(),
2377 Value.getStructBase(BaseIndex), Kind,
2378 BS.getBeginLoc(), CheckedTemps))
2379 return false;
2380 ++BaseIndex;
2381 }
2382 }
2383 for (const auto *I : RD->fields()) {
2384 if (I->isUnnamedBitfield())
2385 continue;
2386
2387 if (!CheckEvaluationResult(CERK, Info, DiagLoc, I->getType(),
2388 Value.getStructField(I->getFieldIndex()),
2389 Kind, I->getLocation(), CheckedTemps))
2390 return false;
2391 }
2392 }
2393
2394 if (Value.isLValue() &&
2395 CERK == CheckEvaluationResultKind::ConstantExpression) {
2396 LValue LVal;
2397 LVal.setFrom(Info.Ctx, Value);
2398 return CheckLValueConstantExpression(Info, DiagLoc, Type, LVal, Kind,
2399 CheckedTemps);
2400 }
2401
2402 if (Value.isMemberPointer() &&
2403 CERK == CheckEvaluationResultKind::ConstantExpression)
2404 return CheckMemberPointerConstantExpression(Info, DiagLoc, Type, Value, Kind);
2405
2406 // Everything else is fine.
2407 return true;
2408}
2409
2410/// Check that this core constant expression value is a valid value for a
2411/// constant expression. If not, report an appropriate diagnostic. Does not
2412/// check that the expression is of literal type.
2413static bool CheckConstantExpression(EvalInfo &Info, SourceLocation DiagLoc,
2414 QualType Type, const APValue &Value,
2415 ConstantExprKind Kind) {
2416 // Nothing to check for a constant expression of type 'cv void'.
2417 if (Type->isVoidType())
2418 return true;
2419
2420 CheckedTemporaries CheckedTemps;
2421 return CheckEvaluationResult(CheckEvaluationResultKind::ConstantExpression,
2422 Info, DiagLoc, Type, Value, Kind,
2423 SourceLocation(), CheckedTemps);
2424}
2425
2426/// Check that this evaluated value is fully-initialized and can be loaded by
2427/// an lvalue-to-rvalue conversion.
2428static bool CheckFullyInitialized(EvalInfo &Info, SourceLocation DiagLoc,
2429 QualType Type, const APValue &Value) {
2430 CheckedTemporaries CheckedTemps;
2431 return CheckEvaluationResult(
2432 CheckEvaluationResultKind::FullyInitialized, Info, DiagLoc, Type, Value,
2433 ConstantExprKind::Normal, SourceLocation(), CheckedTemps);
2434}
2435
2436/// Enforce C++2a [expr.const]/4.17, which disallows new-expressions unless
2437/// "the allocated storage is deallocated within the evaluation".
2438static bool CheckMemoryLeaks(EvalInfo &Info) {
2439 if (!Info.HeapAllocs.empty()) {
2440 // We can still fold to a constant despite a compile-time memory leak,
2441 // so long as the heap allocation isn't referenced in the result (we check
2442 // that in CheckConstantExpression).
2443 Info.CCEDiag(Info.HeapAllocs.begin()->second.AllocExpr,
2444 diag::note_constexpr_memory_leak)
2445 << unsigned(Info.HeapAllocs.size() - 1);
2446 }
2447 return true;
2448}
2449
2450static bool EvalPointerValueAsBool(const APValue &Value, bool &Result) {
2451 // A null base expression indicates a null pointer. These are always
2452 // evaluatable, and they are false unless the offset is zero.
2453 if (!Value.getLValueBase()) {
2454 Result = !Value.getLValueOffset().isZero();
2455 return true;
2456 }
2457
2458 // We have a non-null base. These are generally known to be true, but if it's
2459 // a weak declaration it can be null at runtime.
2460 Result = true;
2461 const ValueDecl *Decl = Value.getLValueBase().dyn_cast<const ValueDecl*>();
2462 return !Decl || !Decl->isWeak();
2463}
2464
2465static bool HandleConversionToBool(const APValue &Val, bool &Result) {
2466 switch (Val.getKind()) {
2467 case APValue::None:
2468 case APValue::Indeterminate:
2469 return false;
2470 case APValue::Int:
2471 Result = Val.getInt().getBoolValue();
2472 return true;
2473 case APValue::FixedPoint:
2474 Result = Val.getFixedPoint().getBoolValue();
2475 return true;
2476 case APValue::Float:
2477 Result = !Val.getFloat().isZero();
2478 return true;
2479 case APValue::ComplexInt:
2480 Result = Val.getComplexIntReal().getBoolValue() ||
2481 Val.getComplexIntImag().getBoolValue();
2482 return true;
2483 case APValue::ComplexFloat:
2484 Result = !Val.getComplexFloatReal().isZero() ||
2485 !Val.getComplexFloatImag().isZero();
2486 return true;
2487 case APValue::LValue:
2488 return EvalPointerValueAsBool(Val, Result);
2489 case APValue::MemberPointer:
2490 Result = Val.getMemberPointerDecl();
2491 return true;
2492 case APValue::Vector:
2493 case APValue::Array:
2494 case APValue::Struct:
2495 case APValue::Union:
2496 case APValue::AddrLabelDiff:
2497 return false;
2498 }
2499
2500 llvm_unreachable("unknown APValue kind")::llvm::llvm_unreachable_internal("unknown APValue kind", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2500)
;
2501}
2502
2503static bool EvaluateAsBooleanCondition(const Expr *E, bool &Result,
2504 EvalInfo &Info) {
2505 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2505, __extension__ __PRETTY_FUNCTION__))
;
2506 assert(E->isPRValue() && "missing lvalue-to-rvalue conv in bool condition")(static_cast <bool> (E->isPRValue() && "missing lvalue-to-rvalue conv in bool condition"
) ? void (0) : __assert_fail ("E->isPRValue() && \"missing lvalue-to-rvalue conv in bool condition\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2506, __extension__ __PRETTY_FUNCTION__))
;
2507 APValue Val;
2508 if (!Evaluate(Val, Info, E))
2509 return false;
2510 return HandleConversionToBool(Val, Result);
2511}
2512
2513template<typename T>
2514static bool HandleOverflow(EvalInfo &Info, const Expr *E,
2515 const T &SrcValue, QualType DestType) {
2516 Info.CCEDiag(E, diag::note_constexpr_overflow)
2517 << SrcValue << DestType;
2518 return Info.noteUndefinedBehavior();
2519}
2520
2521static bool HandleFloatToIntCast(EvalInfo &Info, const Expr *E,
2522 QualType SrcType, const APFloat &Value,
2523 QualType DestType, APSInt &Result) {
2524 unsigned DestWidth = Info.Ctx.getIntWidth(DestType);
2525 // Determine whether we are converting to unsigned or signed.
2526 bool DestSigned = DestType->isSignedIntegerOrEnumerationType();
2527
2528 Result = APSInt(DestWidth, !DestSigned);
2529 bool ignored;
2530 if (Value.convertToInteger(Result, llvm::APFloat::rmTowardZero, &ignored)
2531 & APFloat::opInvalidOp)
2532 return HandleOverflow(Info, E, Value, DestType);
2533 return true;
2534}
2535
2536/// Get rounding mode used for evaluation of the specified expression.
2537/// \param[out] DynamicRM Is set to true is the requested rounding mode is
2538/// dynamic.
2539/// If rounding mode is unknown at compile time, still try to evaluate the
2540/// expression. If the result is exact, it does not depend on rounding mode.
2541/// So return "tonearest" mode instead of "dynamic".
2542static llvm::RoundingMode getActiveRoundingMode(EvalInfo &Info, const Expr *E,
2543 bool &DynamicRM) {
2544 llvm::RoundingMode RM =
2545 E->getFPFeaturesInEffect(Info.Ctx.getLangOpts()).getRoundingMode();
2546 DynamicRM = (RM == llvm::RoundingMode::Dynamic);
2547 if (DynamicRM)
2548 RM = llvm::RoundingMode::NearestTiesToEven;
2549 return RM;
2550}
2551
2552/// Check if the given evaluation result is allowed for constant evaluation.
2553static bool checkFloatingPointResult(EvalInfo &Info, const Expr *E,
2554 APFloat::opStatus St) {
2555 // In a constant context, assume that any dynamic rounding mode or FP
2556 // exception state matches the default floating-point environment.
2557 if (Info.InConstantContext)
2558 return true;
2559
2560 FPOptions FPO = E->getFPFeaturesInEffect(Info.Ctx.getLangOpts());
2561 if ((St & APFloat::opInexact) &&
2562 FPO.getRoundingMode() == llvm::RoundingMode::Dynamic) {
2563 // Inexact result means that it depends on rounding mode. If the requested
2564 // mode is dynamic, the evaluation cannot be made in compile time.
2565 Info.FFDiag(E, diag::note_constexpr_dynamic_rounding);
2566 return false;
2567 }
2568
2569 if ((St != APFloat::opOK) &&
2570 (FPO.getRoundingMode() == llvm::RoundingMode::Dynamic ||
2571 FPO.getFPExceptionMode() != LangOptions::FPE_Ignore ||
2572 FPO.getAllowFEnvAccess())) {
2573 Info.FFDiag(E, diag::note_constexpr_float_arithmetic_strict);
2574 return false;
2575 }
2576
2577 if ((St & APFloat::opStatus::opInvalidOp) &&
2578 FPO.getFPExceptionMode() != LangOptions::FPE_Ignore) {
2579 // There is no usefully definable result.
2580 Info.FFDiag(E);
2581 return false;
2582 }
2583
2584 // FIXME: if:
2585 // - evaluation triggered other FP exception, and
2586 // - exception mode is not "ignore", and
2587 // - the expression being evaluated is not a part of global variable
2588 // initializer,
2589 // the evaluation probably need to be rejected.
2590 return true;
2591}
2592
2593static bool HandleFloatToFloatCast(EvalInfo &Info, const Expr *E,
2594 QualType SrcType, QualType DestType,
2595 APFloat &Result) {
2596 assert(isa<CastExpr>(E) || isa<CompoundAssignOperator>(E))(static_cast <bool> (isa<CastExpr>(E) || isa<CompoundAssignOperator
>(E)) ? void (0) : __assert_fail ("isa<CastExpr>(E) || isa<CompoundAssignOperator>(E)"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2596, __extension__ __PRETTY_FUNCTION__))
;
2597 bool DynamicRM;
2598 llvm::RoundingMode RM = getActiveRoundingMode(Info, E, DynamicRM);
2599 APFloat::opStatus St;
2600 APFloat Value = Result;
2601 bool ignored;
2602 St = Result.convert(Info.Ctx.getFloatTypeSemantics(DestType), RM, &ignored);
2603 return checkFloatingPointResult(Info, E, St);
2604}
2605
2606static APSInt HandleIntToIntCast(EvalInfo &Info, const Expr *E,
2607 QualType DestType, QualType SrcType,
2608 const APSInt &Value) {
2609 unsigned DestWidth = Info.Ctx.getIntWidth(DestType);
2610 // Figure out if this is a truncate, extend or noop cast.
2611 // If the input is signed, do a sign extend, noop, or truncate.
2612 APSInt Result = Value.extOrTrunc(DestWidth);
2613 Result.setIsUnsigned(DestType->isUnsignedIntegerOrEnumerationType());
2614 if (DestType->isBooleanType())
2615 Result = Value.getBoolValue();
2616 return Result;
2617}
2618
2619static bool HandleIntToFloatCast(EvalInfo &Info, const Expr *E,
2620 const FPOptions FPO,
2621 QualType SrcType, const APSInt &Value,
2622 QualType DestType, APFloat &Result) {
2623 Result = APFloat(Info.Ctx.getFloatTypeSemantics(DestType), 1);
2624 APFloat::opStatus St = Result.convertFromAPInt(Value, Value.isSigned(),
2625 APFloat::rmNearestTiesToEven);
2626 if (!Info.InConstantContext && St != llvm::APFloatBase::opOK &&
2627 FPO.isFPConstrained()) {
2628 Info.FFDiag(E, diag::note_constexpr_float_arithmetic_strict);
2629 return false;
2630 }
2631 return true;
2632}
2633
2634static bool truncateBitfieldValue(EvalInfo &Info, const Expr *E,
2635 APValue &Value, const FieldDecl *FD) {
2636 assert(FD->isBitField() && "truncateBitfieldValue on non-bitfield")(static_cast <bool> (FD->isBitField() && "truncateBitfieldValue on non-bitfield"
) ? void (0) : __assert_fail ("FD->isBitField() && \"truncateBitfieldValue on non-bitfield\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2636, __extension__ __PRETTY_FUNCTION__))
;
2637
2638 if (!Value.isInt()) {
2639 // Trying to store a pointer-cast-to-integer into a bitfield.
2640 // FIXME: In this case, we should provide the diagnostic for casting
2641 // a pointer to an integer.
2642 assert(Value.isLValue() && "integral value neither int nor lvalue?")(static_cast <bool> (Value.isLValue() && "integral value neither int nor lvalue?"
) ? void (0) : __assert_fail ("Value.isLValue() && \"integral value neither int nor lvalue?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2642, __extension__ __PRETTY_FUNCTION__))
;
2643 Info.FFDiag(E);
2644 return false;
2645 }
2646
2647 APSInt &Int = Value.getInt();
2648 unsigned OldBitWidth = Int.getBitWidth();
2649 unsigned NewBitWidth = FD->getBitWidthValue(Info.Ctx);
2650 if (NewBitWidth < OldBitWidth)
2651 Int = Int.trunc(NewBitWidth).extend(OldBitWidth);
2652 return true;
2653}
2654
2655static bool EvalAndBitcastToAPInt(EvalInfo &Info, const Expr *E,
2656 llvm::APInt &Res) {
2657 APValue SVal;
2658 if (!Evaluate(SVal, Info, E))
2659 return false;
2660 if (SVal.isInt()) {
2661 Res = SVal.getInt();
2662 return true;
2663 }
2664 if (SVal.isFloat()) {
2665 Res = SVal.getFloat().bitcastToAPInt();
2666 return true;
2667 }
2668 if (SVal.isVector()) {
2669 QualType VecTy = E->getType();
2670 unsigned VecSize = Info.Ctx.getTypeSize(VecTy);
2671 QualType EltTy = VecTy->castAs<VectorType>()->getElementType();
2672 unsigned EltSize = Info.Ctx.getTypeSize(EltTy);
2673 bool BigEndian = Info.Ctx.getTargetInfo().isBigEndian();
2674 Res = llvm::APInt::getZero(VecSize);
2675 for (unsigned i = 0; i < SVal.getVectorLength(); i++) {
2676 APValue &Elt = SVal.getVectorElt(i);
2677 llvm::APInt EltAsInt;
2678 if (Elt.isInt()) {
2679 EltAsInt = Elt.getInt();
2680 } else if (Elt.isFloat()) {
2681 EltAsInt = Elt.getFloat().bitcastToAPInt();
2682 } else {
2683 // Don't try to handle vectors of anything other than int or float
2684 // (not sure if it's possible to hit this case).
2685 Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
2686 return false;
2687 }
2688 unsigned BaseEltSize = EltAsInt.getBitWidth();
2689 if (BigEndian)
2690 Res |= EltAsInt.zextOrTrunc(VecSize).rotr(i*EltSize+BaseEltSize);
2691 else
2692 Res |= EltAsInt.zextOrTrunc(VecSize).rotl(i*EltSize);
2693 }
2694 return true;
2695 }
2696 // Give up if the input isn't an int, float, or vector. For example, we
2697 // reject "(v4i16)(intptr_t)&a".
2698 Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
2699 return false;
2700}
2701
2702/// Perform the given integer operation, which is known to need at most BitWidth
2703/// bits, and check for overflow in the original type (if that type was not an
2704/// unsigned type).
2705template<typename Operation>
2706static bool CheckedIntArithmetic(EvalInfo &Info, const Expr *E,
2707 const APSInt &LHS, const APSInt &RHS,
2708 unsigned BitWidth, Operation Op,
2709 APSInt &Result) {
2710 if (LHS.isUnsigned()) {
2711 Result = Op(LHS, RHS);
2712 return true;
2713 }
2714
2715 APSInt Value(Op(LHS.extend(BitWidth), RHS.extend(BitWidth)), false);
2716 Result = Value.trunc(LHS.getBitWidth());
2717 if (Result.extend(BitWidth) != Value) {
2718 if (Info.checkingForUndefinedBehavior())
2719 Info.Ctx.getDiagnostics().Report(E->getExprLoc(),
2720 diag::warn_integer_constant_overflow)
2721 << toString(Result, 10) << E->getType();
2722 return HandleOverflow(Info, E, Value, E->getType());
2723 }
2724 return true;
2725}
2726
2727/// Perform the given binary integer operation.
2728static bool handleIntIntBinOp(EvalInfo &Info, const Expr *E, const APSInt &LHS,
2729 BinaryOperatorKind Opcode, APSInt RHS,
2730 APSInt &Result) {
2731 switch (Opcode) {
2732 default:
2733 Info.FFDiag(E);
2734 return false;
2735 case BO_Mul:
2736 return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() * 2,
2737 std::multiplies<APSInt>(), Result);
2738 case BO_Add:
2739 return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() + 1,
2740 std::plus<APSInt>(), Result);
2741 case BO_Sub:
2742 return CheckedIntArithmetic(Info, E, LHS, RHS, LHS.getBitWidth() + 1,
2743 std::minus<APSInt>(), Result);
2744 case BO_And: Result = LHS & RHS; return true;
2745 case BO_Xor: Result = LHS ^ RHS; return true;
2746 case BO_Or: Result = LHS | RHS; return true;
2747 case BO_Div:
2748 case BO_Rem:
2749 if (RHS == 0) {
2750 Info.FFDiag(E, diag::note_expr_divide_by_zero);
2751 return false;
2752 }
2753 Result = (Opcode == BO_Rem ? LHS % RHS : LHS / RHS);
2754 // Check for overflow case: INT_MIN / -1 or INT_MIN % -1. APSInt supports
2755 // this operation and gives the two's complement result.
2756 if (RHS.isNegative() && RHS.isAllOnes() && LHS.isSigned() &&
2757 LHS.isMinSignedValue())
2758 return HandleOverflow(Info, E, -LHS.extend(LHS.getBitWidth() + 1),
2759 E->getType());
2760 return true;
2761 case BO_Shl: {
2762 if (Info.getLangOpts().OpenCL)
2763 // OpenCL 6.3j: shift values are effectively % word size of LHS.
2764 RHS &= APSInt(llvm::APInt(RHS.getBitWidth(),
2765 static_cast<uint64_t>(LHS.getBitWidth() - 1)),
2766 RHS.isUnsigned());
2767 else if (RHS.isSigned() && RHS.isNegative()) {
2768 // During constant-folding, a negative shift is an opposite shift. Such
2769 // a shift is not a constant expression.
2770 Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHS;
2771 RHS = -RHS;
2772 goto shift_right;
2773 }
2774 shift_left:
2775 // C++11 [expr.shift]p1: Shift width must be less than the bit width of
2776 // the shifted type.
2777 unsigned SA = (unsigned) RHS.getLimitedValue(LHS.getBitWidth()-1);
2778 if (SA != RHS) {
2779 Info.CCEDiag(E, diag::note_constexpr_large_shift)
2780 << RHS << E->getType() << LHS.getBitWidth();
2781 } else if (LHS.isSigned() && !Info.getLangOpts().CPlusPlus20) {
2782 // C++11 [expr.shift]p2: A signed left shift must have a non-negative
2783 // operand, and must not overflow the corresponding unsigned type.
2784 // C++2a [expr.shift]p2: E1 << E2 is the unique value congruent to
2785 // E1 x 2^E2 module 2^N.
2786 if (LHS.isNegative())
2787 Info.CCEDiag(E, diag::note_constexpr_lshift_of_negative) << LHS;
2788 else if (LHS.countLeadingZeros() < SA)
2789 Info.CCEDiag(E, diag::note_constexpr_lshift_discards);
2790 }
2791 Result = LHS << SA;
2792 return true;
2793 }
2794 case BO_Shr: {
2795 if (Info.getLangOpts().OpenCL)
2796 // OpenCL 6.3j: shift values are effectively % word size of LHS.
2797 RHS &= APSInt(llvm::APInt(RHS.getBitWidth(),
2798 static_cast<uint64_t>(LHS.getBitWidth() - 1)),
2799 RHS.isUnsigned());
2800 else if (RHS.isSigned() && RHS.isNegative()) {
2801 // During constant-folding, a negative shift is an opposite shift. Such a
2802 // shift is not a constant expression.
2803 Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHS;
2804 RHS = -RHS;
2805 goto shift_left;
2806 }
2807 shift_right:
2808 // C++11 [expr.shift]p1: Shift width must be less than the bit width of the
2809 // shifted type.
2810 unsigned SA = (unsigned) RHS.getLimitedValue(LHS.getBitWidth()-1);
2811 if (SA != RHS)
2812 Info.CCEDiag(E, diag::note_constexpr_large_shift)
2813 << RHS << E->getType() << LHS.getBitWidth();
2814 Result = LHS >> SA;
2815 return true;
2816 }
2817
2818 case BO_LT: Result = LHS < RHS; return true;
2819 case BO_GT: Result = LHS > RHS; return true;
2820 case BO_LE: Result = LHS <= RHS; return true;
2821 case BO_GE: Result = LHS >= RHS; return true;
2822 case BO_EQ: Result = LHS == RHS; return true;
2823 case BO_NE: Result = LHS != RHS; return true;
2824 case BO_Cmp:
2825 llvm_unreachable("BO_Cmp should be handled elsewhere")::llvm::llvm_unreachable_internal("BO_Cmp should be handled elsewhere"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2825)
;
2826 }
2827}
2828
2829/// Perform the given binary floating-point operation, in-place, on LHS.
2830static bool handleFloatFloatBinOp(EvalInfo &Info, const BinaryOperator *E,
2831 APFloat &LHS, BinaryOperatorKind Opcode,
2832 const APFloat &RHS) {
2833 bool DynamicRM;
2834 llvm::RoundingMode RM = getActiveRoundingMode(Info, E, DynamicRM);
2835 APFloat::opStatus St;
2836 switch (Opcode) {
2837 default:
2838 Info.FFDiag(E);
2839 return false;
2840 case BO_Mul:
2841 St = LHS.multiply(RHS, RM);
2842 break;
2843 case BO_Add:
2844 St = LHS.add(RHS, RM);
2845 break;
2846 case BO_Sub:
2847 St = LHS.subtract(RHS, RM);
2848 break;
2849 case BO_Div:
2850 // [expr.mul]p4:
2851 // If the second operand of / or % is zero the behavior is undefined.
2852 if (RHS.isZero())
2853 Info.CCEDiag(E, diag::note_expr_divide_by_zero);
2854 St = LHS.divide(RHS, RM);
2855 break;
2856 }
2857
2858 // [expr.pre]p4:
2859 // If during the evaluation of an expression, the result is not
2860 // mathematically defined [...], the behavior is undefined.
2861 // FIXME: C++ rules require us to not conform to IEEE 754 here.
2862 if (LHS.isNaN()) {
2863 Info.CCEDiag(E, diag::note_constexpr_float_arithmetic) << LHS.isNaN();
2864 return Info.noteUndefinedBehavior();
2865 }
2866
2867 return checkFloatingPointResult(Info, E, St);
2868}
2869
2870static bool handleLogicalOpForVector(const APInt &LHSValue,
2871 BinaryOperatorKind Opcode,
2872 const APInt &RHSValue, APInt &Result) {
2873 bool LHS = (LHSValue != 0);
2874 bool RHS = (RHSValue != 0);
2875
2876 if (Opcode == BO_LAnd)
2877 Result = LHS && RHS;
2878 else
2879 Result = LHS || RHS;
2880 return true;
2881}
2882static bool handleLogicalOpForVector(const APFloat &LHSValue,
2883 BinaryOperatorKind Opcode,
2884 const APFloat &RHSValue, APInt &Result) {
2885 bool LHS = !LHSValue.isZero();
2886 bool RHS = !RHSValue.isZero();
2887
2888 if (Opcode == BO_LAnd)
2889 Result = LHS && RHS;
2890 else
2891 Result = LHS || RHS;
2892 return true;
2893}
2894
2895static bool handleLogicalOpForVector(const APValue &LHSValue,
2896 BinaryOperatorKind Opcode,
2897 const APValue &RHSValue, APInt &Result) {
2898 // The result is always an int type, however operands match the first.
2899 if (LHSValue.getKind() == APValue::Int)
2900 return handleLogicalOpForVector(LHSValue.getInt(), Opcode,
2901 RHSValue.getInt(), Result);
2902 assert(LHSValue.getKind() == APValue::Float && "Should be no other options")(static_cast <bool> (LHSValue.getKind() == APValue::Float
&& "Should be no other options") ? void (0) : __assert_fail
("LHSValue.getKind() == APValue::Float && \"Should be no other options\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2902, __extension__ __PRETTY_FUNCTION__))
;
2903 return handleLogicalOpForVector(LHSValue.getFloat(), Opcode,
2904 RHSValue.getFloat(), Result);
2905}
2906
2907template <typename APTy>
2908static bool
2909handleCompareOpForVectorHelper(const APTy &LHSValue, BinaryOperatorKind Opcode,
2910 const APTy &RHSValue, APInt &Result) {
2911 switch (Opcode) {
2912 default:
2913 llvm_unreachable("unsupported binary operator")::llvm::llvm_unreachable_internal("unsupported binary operator"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2913)
;
2914 case BO_EQ:
2915 Result = (LHSValue == RHSValue);
2916 break;
2917 case BO_NE:
2918 Result = (LHSValue != RHSValue);
2919 break;
2920 case BO_LT:
2921 Result = (LHSValue < RHSValue);
2922 break;
2923 case BO_GT:
2924 Result = (LHSValue > RHSValue);
2925 break;
2926 case BO_LE:
2927 Result = (LHSValue <= RHSValue);
2928 break;
2929 case BO_GE:
2930 Result = (LHSValue >= RHSValue);
2931 break;
2932 }
2933
2934 return true;
2935}
2936
2937static bool handleCompareOpForVector(const APValue &LHSValue,
2938 BinaryOperatorKind Opcode,
2939 const APValue &RHSValue, APInt &Result) {
2940 // The result is always an int type, however operands match the first.
2941 if (LHSValue.getKind() == APValue::Int)
2942 return handleCompareOpForVectorHelper(LHSValue.getInt(), Opcode,
2943 RHSValue.getInt(), Result);
2944 assert(LHSValue.getKind() == APValue::Float && "Should be no other options")(static_cast <bool> (LHSValue.getKind() == APValue::Float
&& "Should be no other options") ? void (0) : __assert_fail
("LHSValue.getKind() == APValue::Float && \"Should be no other options\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2944, __extension__ __PRETTY_FUNCTION__))
;
2945 return handleCompareOpForVectorHelper(LHSValue.getFloat(), Opcode,
2946 RHSValue.getFloat(), Result);
2947}
2948
2949// Perform binary operations for vector types, in place on the LHS.
2950static bool handleVectorVectorBinOp(EvalInfo &Info, const BinaryOperator *E,
2951 BinaryOperatorKind Opcode,
2952 APValue &LHSValue,
2953 const APValue &RHSValue) {
2954 assert(Opcode != BO_PtrMemD && Opcode != BO_PtrMemI &&(static_cast <bool> (Opcode != BO_PtrMemD && Opcode
!= BO_PtrMemI && "Operation not supported on vector types"
) ? void (0) : __assert_fail ("Opcode != BO_PtrMemD && Opcode != BO_PtrMemI && \"Operation not supported on vector types\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2955, __extension__ __PRETTY_FUNCTION__))
2955 "Operation not supported on vector types")(static_cast <bool> (Opcode != BO_PtrMemD && Opcode
!= BO_PtrMemI && "Operation not supported on vector types"
) ? void (0) : __assert_fail ("Opcode != BO_PtrMemD && Opcode != BO_PtrMemI && \"Operation not supported on vector types\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2955, __extension__ __PRETTY_FUNCTION__))
;
2956
2957 const auto *VT = E->getType()->castAs<VectorType>();
2958 unsigned NumElements = VT->getNumElements();
2959 QualType EltTy = VT->getElementType();
2960
2961 // In the cases (typically C as I've observed) where we aren't evaluating
2962 // constexpr but are checking for cases where the LHS isn't yet evaluatable,
2963 // just give up.
2964 if (!LHSValue.isVector()) {
2965 assert(LHSValue.isLValue() &&(static_cast <bool> (LHSValue.isLValue() && "A vector result that isn't a vector OR uncalculated LValue"
) ? void (0) : __assert_fail ("LHSValue.isLValue() && \"A vector result that isn't a vector OR uncalculated LValue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2966, __extension__ __PRETTY_FUNCTION__))
2966 "A vector result that isn't a vector OR uncalculated LValue")(static_cast <bool> (LHSValue.isLValue() && "A vector result that isn't a vector OR uncalculated LValue"
) ? void (0) : __assert_fail ("LHSValue.isLValue() && \"A vector result that isn't a vector OR uncalculated LValue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2966, __extension__ __PRETTY_FUNCTION__))
;
2967 Info.FFDiag(E);
2968 return false;
2969 }
2970
2971 assert(LHSValue.getVectorLength() == NumElements &&(static_cast <bool> (LHSValue.getVectorLength() == NumElements
&& RHSValue.getVectorLength() == NumElements &&
"Different vector sizes") ? void (0) : __assert_fail ("LHSValue.getVectorLength() == NumElements && RHSValue.getVectorLength() == NumElements && \"Different vector sizes\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2972, __extension__ __PRETTY_FUNCTION__))
2972 RHSValue.getVectorLength() == NumElements && "Different vector sizes")(static_cast <bool> (LHSValue.getVectorLength() == NumElements
&& RHSValue.getVectorLength() == NumElements &&
"Different vector sizes") ? void (0) : __assert_fail ("LHSValue.getVectorLength() == NumElements && RHSValue.getVectorLength() == NumElements && \"Different vector sizes\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 2972, __extension__ __PRETTY_FUNCTION__))
;
2973
2974 SmallVector<APValue, 4> ResultElements;
2975
2976 for (unsigned EltNum = 0; EltNum < NumElements; ++EltNum) {
2977 APValue LHSElt = LHSValue.getVectorElt(EltNum);
2978 APValue RHSElt = RHSValue.getVectorElt(EltNum);
2979
2980 if (EltTy->isIntegerType()) {
2981 APSInt EltResult{Info.Ctx.getIntWidth(EltTy),
2982 EltTy->isUnsignedIntegerType()};
2983 bool Success = true;
2984
2985 if (BinaryOperator::isLogicalOp(Opcode))
2986 Success = handleLogicalOpForVector(LHSElt, Opcode, RHSElt, EltResult);
2987 else if (BinaryOperator::isComparisonOp(Opcode))
2988 Success = handleCompareOpForVector(LHSElt, Opcode, RHSElt, EltResult);
2989 else
2990 Success = handleIntIntBinOp(Info, E, LHSElt.getInt(), Opcode,
2991 RHSElt.getInt(), EltResult);
2992
2993 if (!Success) {
2994 Info.FFDiag(E);
2995 return false;
2996 }
2997 ResultElements.emplace_back(EltResult);
2998
2999 } else if (EltTy->isFloatingType()) {
3000 assert(LHSElt.getKind() == APValue::Float &&(static_cast <bool> (LHSElt.getKind() == APValue::Float
&& RHSElt.getKind() == APValue::Float && "Mismatched LHS/RHS/Result Type"
) ? void (0) : __assert_fail ("LHSElt.getKind() == APValue::Float && RHSElt.getKind() == APValue::Float && \"Mismatched LHS/RHS/Result Type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3002, __extension__ __PRETTY_FUNCTION__))
3001 RHSElt.getKind() == APValue::Float &&(static_cast <bool> (LHSElt.getKind() == APValue::Float
&& RHSElt.getKind() == APValue::Float && "Mismatched LHS/RHS/Result Type"
) ? void (0) : __assert_fail ("LHSElt.getKind() == APValue::Float && RHSElt.getKind() == APValue::Float && \"Mismatched LHS/RHS/Result Type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3002, __extension__ __PRETTY_FUNCTION__))
3002 "Mismatched LHS/RHS/Result Type")(static_cast <bool> (LHSElt.getKind() == APValue::Float
&& RHSElt.getKind() == APValue::Float && "Mismatched LHS/RHS/Result Type"
) ? void (0) : __assert_fail ("LHSElt.getKind() == APValue::Float && RHSElt.getKind() == APValue::Float && \"Mismatched LHS/RHS/Result Type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3002, __extension__ __PRETTY_FUNCTION__))
;
3003 APFloat LHSFloat = LHSElt.getFloat();
3004
3005 if (!handleFloatFloatBinOp(Info, E, LHSFloat, Opcode,
3006 RHSElt.getFloat())) {
3007 Info.FFDiag(E);
3008 return false;
3009 }
3010
3011 ResultElements.emplace_back(LHSFloat);
3012 }
3013 }
3014
3015 LHSValue = APValue(ResultElements.data(), ResultElements.size());
3016 return true;
3017}
3018
3019/// Cast an lvalue referring to a base subobject to a derived class, by
3020/// truncating the lvalue's path to the given length.
3021static bool CastToDerivedClass(EvalInfo &Info, const Expr *E, LValue &Result,
3022 const RecordDecl *TruncatedType,
3023 unsigned TruncatedElements) {
3024 SubobjectDesignator &D = Result.Designator;
3025
3026 // Check we actually point to a derived class object.
3027 if (TruncatedElements == D.Entries.size())
3028 return true;
3029 assert(TruncatedElements >= D.MostDerivedPathLength &&(static_cast <bool> (TruncatedElements >= D.MostDerivedPathLength
&& "not casting to a derived class") ? void (0) : __assert_fail
("TruncatedElements >= D.MostDerivedPathLength && \"not casting to a derived class\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3030, __extension__ __PRETTY_FUNCTION__))
3030 "not casting to a derived class")(static_cast <bool> (TruncatedElements >= D.MostDerivedPathLength
&& "not casting to a derived class") ? void (0) : __assert_fail
("TruncatedElements >= D.MostDerivedPathLength && \"not casting to a derived class\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3030, __extension__ __PRETTY_FUNCTION__))
;
3031 if (!Result.checkSubobject(Info, E, CSK_Derived))
3032 return false;
3033
3034 // Truncate the path to the subobject, and remove any derived-to-base offsets.
3035 const RecordDecl *RD = TruncatedType;
3036 for (unsigned I = TruncatedElements, N = D.Entries.size(); I != N; ++I) {
3037 if (RD->isInvalidDecl()) return false;
3038 const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
3039 const CXXRecordDecl *Base = getAsBaseClass(D.Entries[I]);
3040 if (isVirtualBaseClass(D.Entries[I]))
3041 Result.Offset -= Layout.getVBaseClassOffset(Base);
3042 else
3043 Result.Offset -= Layout.getBaseClassOffset(Base);
3044 RD = Base;
3045 }
3046 D.Entries.resize(TruncatedElements);
3047 return true;
3048}
3049
3050static bool HandleLValueDirectBase(EvalInfo &Info, const Expr *E, LValue &Obj,
3051 const CXXRecordDecl *Derived,
3052 const CXXRecordDecl *Base,
3053 const ASTRecordLayout *RL = nullptr) {
3054 if (!RL) {
3055 if (Derived->isInvalidDecl()) return false;
3056 RL = &Info.Ctx.getASTRecordLayout(Derived);
3057 }
3058
3059 Obj.getLValueOffset() += RL->getBaseClassOffset(Base);
3060 Obj.addDecl(Info, E, Base, /*Virtual*/ false);
3061 return true;
3062}
3063
3064static bool HandleLValueBase(EvalInfo &Info, const Expr *E, LValue &Obj,
3065 const CXXRecordDecl *DerivedDecl,
3066 const CXXBaseSpecifier *Base) {
3067 const CXXRecordDecl *BaseDecl = Base->getType()->getAsCXXRecordDecl();
3068
3069 if (!Base->isVirtual())
3070 return HandleLValueDirectBase(Info, E, Obj, DerivedDecl, BaseDecl);
3071
3072 SubobjectDesignator &D = Obj.Designator;
3073 if (D.Invalid)
3074 return false;
3075
3076 // Extract most-derived object and corresponding type.
3077 DerivedDecl = D.MostDerivedType->getAsCXXRecordDecl();
3078 if (!CastToDerivedClass(Info, E, Obj, DerivedDecl, D.MostDerivedPathLength))
3079 return false;
3080
3081 // Find the virtual base class.
3082 if (DerivedDecl->isInvalidDecl()) return false;
3083 const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(DerivedDecl);
3084 Obj.getLValueOffset() += Layout.getVBaseClassOffset(BaseDecl);
3085 Obj.addDecl(Info, E, BaseDecl, /*Virtual*/ true);
3086 return true;
3087}
3088
3089static bool HandleLValueBasePath(EvalInfo &Info, const CastExpr *E,
3090 QualType Type, LValue &Result) {
3091 for (CastExpr::path_const_iterator PathI = E->path_begin(),
3092 PathE = E->path_end();
3093 PathI != PathE; ++PathI) {
3094 if (!HandleLValueBase(Info, E, Result, Type->getAsCXXRecordDecl(),
3095 *PathI))
3096 return false;
3097 Type = (*PathI)->getType();
3098 }
3099 return true;
3100}
3101
3102/// Cast an lvalue referring to a derived class to a known base subobject.
3103static bool CastToBaseClass(EvalInfo &Info, const Expr *E, LValue &Result,
3104 const CXXRecordDecl *DerivedRD,
3105 const CXXRecordDecl *BaseRD) {
3106 CXXBasePaths Paths(/*FindAmbiguities=*/false,
3107 /*RecordPaths=*/true, /*DetectVirtual=*/false);
3108 if (!DerivedRD->isDerivedFrom(BaseRD, Paths))
3109 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-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3109)
;
3110
3111 for (CXXBasePathElement &Elem : Paths.front())
3112 if (!HandleLValueBase(Info, E, Result, Elem.Class, Elem.Base))
3113 return false;
3114 return true;
3115}
3116
3117/// Update LVal to refer to the given field, which must be a member of the type
3118/// currently described by LVal.
3119static bool HandleLValueMember(EvalInfo &Info, const Expr *E, LValue &LVal,
3120 const FieldDecl *FD,
3121 const ASTRecordLayout *RL = nullptr) {
3122 if (!RL) {
3123 if (FD->getParent()->isInvalidDecl()) return false;
3124 RL = &Info.Ctx.getASTRecordLayout(FD->getParent());
3125 }
3126
3127 unsigned I = FD->getFieldIndex();
3128 LVal.adjustOffset(Info.Ctx.toCharUnitsFromBits(RL->getFieldOffset(I)));
3129 LVal.addDecl(Info, E, FD);
3130 return true;
3131}
3132
3133/// Update LVal to refer to the given indirect field.
3134static bool HandleLValueIndirectMember(EvalInfo &Info, const Expr *E,
3135 LValue &LVal,
3136 const IndirectFieldDecl *IFD) {
3137 for (const auto *C : IFD->chain())
3138 if (!HandleLValueMember(Info, E, LVal, cast<FieldDecl>(C)))
3139 return false;
3140 return true;
3141}
3142
3143/// Get the size of the given type in char units.
3144static bool HandleSizeof(EvalInfo &Info, SourceLocation Loc,
3145 QualType Type, CharUnits &Size) {
3146 // sizeof(void), __alignof__(void), sizeof(function) = 1 as a gcc
3147 // extension.
3148 if (Type->isVoidType() || Type->isFunctionType()) {
3149 Size = CharUnits::One();
3150 return true;
3151 }
3152
3153 if (Type->isDependentType()) {
3154 Info.FFDiag(Loc);
3155 return false;
3156 }
3157
3158 if (!Type->isConstantSizeType()) {
3159 // sizeof(vla) is not a constantexpr: C99 6.5.3.4p2.
3160 // FIXME: Better diagnostic.
3161 Info.FFDiag(Loc);
3162 return false;
3163 }
3164
3165 Size = Info.Ctx.getTypeSizeInChars(Type);
3166 return true;
3167}
3168
3169/// Update a pointer value to model pointer arithmetic.
3170/// \param Info - Information about the ongoing evaluation.
3171/// \param E - The expression being evaluated, for diagnostic purposes.
3172/// \param LVal - The pointer value to be updated.
3173/// \param EltTy - The pointee type represented by LVal.
3174/// \param Adjustment - The adjustment, in objects of type EltTy, to add.
3175static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E,
3176 LValue &LVal, QualType EltTy,
3177 APSInt Adjustment) {
3178 CharUnits SizeOfPointee;
3179 if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfPointee))
29
Called C++ object pointer is null
3180 return false;
3181
3182 LVal.adjustOffsetAndIndex(Info, E, Adjustment, SizeOfPointee);
3183 return true;
3184}
3185
3186static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E,
3187 LValue &LVal, QualType EltTy,
3188 int64_t Adjustment) {
3189 return HandleLValueArrayAdjustment(Info, E, LVal, EltTy,
27
Passing null pointer value via 2nd parameter 'E'
28
Calling 'HandleLValueArrayAdjustment'
3190 APSInt::get(Adjustment));
3191}
3192
3193/// Update an lvalue to refer to a component of a complex number.
3194/// \param Info - Information about the ongoing evaluation.
3195/// \param LVal - The lvalue to be updated.
3196/// \param EltTy - The complex number's component type.
3197/// \param Imag - False for the real component, true for the imaginary.
3198static bool HandleLValueComplexElement(EvalInfo &Info, const Expr *E,
3199 LValue &LVal, QualType EltTy,
3200 bool Imag) {
3201 if (Imag) {
3202 CharUnits SizeOfComponent;
3203 if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfComponent))
3204 return false;
3205 LVal.Offset += SizeOfComponent;
3206 }
3207 LVal.addComplex(Info, E, EltTy, Imag);
3208 return true;
3209}
3210
3211/// Try to evaluate the initializer for a variable declaration.
3212///
3213/// \param Info Information about the ongoing evaluation.
3214/// \param E An expression to be used when printing diagnostics.
3215/// \param VD The variable whose initializer should be obtained.
3216/// \param Version The version of the variable within the frame.
3217/// \param Frame The frame in which the variable was created. Must be null
3218/// if this variable is not local to the evaluation.
3219/// \param Result Filled in with a pointer to the value of the variable.
3220static bool evaluateVarDeclInit(EvalInfo &Info, const Expr *E,
3221 const VarDecl *VD, CallStackFrame *Frame,
3222 unsigned Version, APValue *&Result) {
3223 APValue::LValueBase Base(VD, Frame ? Frame->Index : 0, Version);
3224
3225 // If this is a local variable, dig out its value.
3226 if (Frame) {
3227 Result = Frame->getTemporary(VD, Version);
3228 if (Result)
3229 return true;
3230
3231 if (!isa<ParmVarDecl>(VD)) {
3232 // Assume variables referenced within a lambda's call operator that were
3233 // not declared within the call operator are captures and during checking
3234 // of a potential constant expression, assume they are unknown constant
3235 // expressions.
3236 assert(isLambdaCallOperator(Frame->Callee) &&(static_cast <bool> (isLambdaCallOperator(Frame->Callee
) && (VD->getDeclContext() != Frame->Callee || VD
->isInitCapture()) && "missing value for local variable"
) ? void (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3238, __extension__ __PRETTY_FUNCTION__))
3237 (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) &&(static_cast <bool> (isLambdaCallOperator(Frame->Callee
) && (VD->getDeclContext() != Frame->Callee || VD
->isInitCapture()) && "missing value for local variable"
) ? void (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3238, __extension__ __PRETTY_FUNCTION__))
3238 "missing value for local variable")(static_cast <bool> (isLambdaCallOperator(Frame->Callee
) && (VD->getDeclContext() != Frame->Callee || VD
->isInitCapture()) && "missing value for local variable"
) ? void (0) : __assert_fail ("isLambdaCallOperator(Frame->Callee) && (VD->getDeclContext() != Frame->Callee || VD->isInitCapture()) && \"missing value for local variable\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3238, __extension__ __PRETTY_FUNCTION__))
;
3239 if (Info.checkingPotentialConstantExpression())
3240 return false;
3241 // FIXME: This diagnostic is bogus; we do support captures. Is this code
3242 // still reachable at all?
3243 Info.FFDiag(E->getBeginLoc(),
3244 diag::note_unimplemented_constexpr_lambda_feature_ast)
3245 << "captures not currently allowed";
3246 return false;
3247 }
3248 }
3249
3250 // If we're currently evaluating the initializer of this declaration, use that
3251 // in-flight value.
3252 if (Info.EvaluatingDecl == Base) {
3253 Result = Info.EvaluatingDeclValue;
3254 return true;
3255 }
3256
3257 if (isa<ParmVarDecl>(VD)) {
3258 // Assume parameters of a potential constant expression are usable in
3259 // constant expressions.
3260 if (!Info.checkingPotentialConstantExpression() ||
3261 !Info.CurrentCall->Callee ||
3262 !Info.CurrentCall->Callee->Equals(VD->getDeclContext())) {
3263 if (Info.getLangOpts().CPlusPlus11) {
3264 Info.FFDiag(E, diag::note_constexpr_function_param_value_unknown)
3265 << VD;
3266 NoteLValueLocation(Info, Base);
3267 } else {
3268 Info.FFDiag(E);
3269 }
3270 }
3271 return false;
3272 }
3273
3274 // Dig out the initializer, and use the declaration which it's attached to.
3275 // FIXME: We should eventually check whether the variable has a reachable
3276 // initializing declaration.
3277 const Expr *Init = VD->getAnyInitializer(VD);
3278 if (!Init) {
3279 // Don't diagnose during potential constant expression checking; an
3280 // initializer might be added later.
3281 if (!Info.checkingPotentialConstantExpression()) {
3282 Info.FFDiag(E, diag::note_constexpr_var_init_unknown, 1)
3283 << VD;
3284 NoteLValueLocation(Info, Base);
3285 }
3286 return false;
3287 }
3288
3289 if (Init->isValueDependent()) {
3290 // The DeclRefExpr is not value-dependent, but the variable it refers to
3291 // has a value-dependent initializer. This should only happen in
3292 // constant-folding cases, where the variable is not actually of a suitable
3293 // type for use in a constant expression (otherwise the DeclRefExpr would
3294 // have been value-dependent too), so diagnose that.
3295 assert(!VD->mightBeUsableInConstantExpressions(Info.Ctx))(static_cast <bool> (!VD->mightBeUsableInConstantExpressions
(Info.Ctx)) ? void (0) : __assert_fail ("!VD->mightBeUsableInConstantExpressions(Info.Ctx)"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3295, __extension__ __PRETTY_FUNCTION__))
;
3296 if (!Info.checkingPotentialConstantExpression()) {
3297 Info.FFDiag(E, Info.getLangOpts().CPlusPlus11
3298 ? diag::note_constexpr_ltor_non_constexpr
3299 : diag::note_constexpr_ltor_non_integral, 1)
3300 << VD << VD->getType();
3301 NoteLValueLocation(Info, Base);
3302 }
3303 return false;
3304 }
3305
3306 // Check that we can fold the initializer. In C++, we will have already done
3307 // this in the cases where it matters for conformance.
3308 if (!VD->evaluateValue()) {
3309 Info.FFDiag(E, diag::note_constexpr_var_init_non_constant, 1) << VD;
3310 NoteLValueLocation(Info, Base);
3311 return false;
3312 }
3313
3314 // Check that the variable is actually usable in constant expressions. For a
3315 // const integral variable or a reference, we might have a non-constant
3316 // initializer that we can nonetheless evaluate the initializer for. Such
3317 // variables are not usable in constant expressions. In C++98, the
3318 // initializer also syntactically needs to be an ICE.
3319 //
3320 // FIXME: We don't diagnose cases that aren't potentially usable in constant
3321 // expressions here; doing so would regress diagnostics for things like
3322 // reading from a volatile constexpr variable.
3323 if ((Info.getLangOpts().CPlusPlus && !VD->hasConstantInitialization() &&
3324 VD->mightBeUsableInConstantExpressions(Info.Ctx)) ||
3325 ((Info.getLangOpts().CPlusPlus || Info.getLangOpts().OpenCL) &&
3326 !Info.getLangOpts().CPlusPlus11 && !VD->hasICEInitializer(Info.Ctx))) {
3327 Info.CCEDiag(E, diag::note_constexpr_var_init_non_constant, 1) << VD;
3328 NoteLValueLocation(Info, Base);
3329 }
3330
3331 // Never use the initializer of a weak variable, not even for constant
3332 // folding. We can't be sure that this is the definition that will be used.
3333 if (VD->isWeak()) {
3334 Info.FFDiag(E, diag::note_constexpr_var_init_weak) << VD;
3335 NoteLValueLocation(Info, Base);
3336 return false;
3337 }
3338
3339 Result = VD->getEvaluatedValue();
3340 return true;
3341}
3342
3343/// Get the base index of the given base class within an APValue representing
3344/// the given derived class.
3345static unsigned getBaseIndex(const CXXRecordDecl *Derived,
3346 const CXXRecordDecl *Base) {
3347 Base = Base->getCanonicalDecl();
3348 unsigned Index = 0;
3349 for (CXXRecordDecl::base_class_const_iterator I = Derived->bases_begin(),
3350 E = Derived->bases_end(); I != E; ++I, ++Index) {
3351 if (I->getType()->getAsCXXRecordDecl()->getCanonicalDecl() == Base)
3352 return Index;
3353 }
3354
3355 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-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3355)
;
3356}
3357
3358/// Extract the value of a character from a string literal.
3359static APSInt extractStringLiteralCharacter(EvalInfo &Info, const Expr *Lit,
3360 uint64_t Index) {
3361 assert(!isa<SourceLocExpr>(Lit) &&(static_cast <bool> (!isa<SourceLocExpr>(Lit) &&
"SourceLocExpr should have already been converted to a StringLiteral"
) ? void (0) : __assert_fail ("!isa<SourceLocExpr>(Lit) && \"SourceLocExpr should have already been converted to a StringLiteral\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3362, __extension__ __PRETTY_FUNCTION__))
3362 "SourceLocExpr should have already been converted to a StringLiteral")(static_cast <bool> (!isa<SourceLocExpr>(Lit) &&
"SourceLocExpr should have already been converted to a StringLiteral"
) ? void (0) : __assert_fail ("!isa<SourceLocExpr>(Lit) && \"SourceLocExpr should have already been converted to a StringLiteral\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3362, __extension__ __PRETTY_FUNCTION__))
;
3363
3364 // FIXME: Support MakeStringConstant
3365 if (const auto *ObjCEnc = dyn_cast<ObjCEncodeExpr>(Lit)) {
3366 std::string Str;
3367 Info.Ctx.getObjCEncodingForType(ObjCEnc->getEncodedType(), Str);
3368 assert(Index <= Str.size() && "Index too large")(static_cast <bool> (Index <= Str.size() && "Index too large"
) ? void (0) : __assert_fail ("Index <= Str.size() && \"Index too large\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3368, __extension__ __PRETTY_FUNCTION__))
;
3369 return APSInt::getUnsigned(Str.c_str()[Index]);
3370 }
3371
3372 if (auto PE = dyn_cast<PredefinedExpr>(Lit))
3373 Lit = PE->getFunctionName();
3374 const StringLiteral *S = cast<StringLiteral>(Lit);
3375 const ConstantArrayType *CAT =
3376 Info.Ctx.getAsConstantArrayType(S->getType());
3377 assert(CAT && "string literal isn't an array")(static_cast <bool> (CAT && "string literal isn't an array"
) ? void (0) : __assert_fail ("CAT && \"string literal isn't an array\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3377, __extension__ __PRETTY_FUNCTION__))
;
3378 QualType CharType = CAT->getElementType();
3379 assert(CharType->isIntegerType() && "unexpected character type")(static_cast <bool> (CharType->isIntegerType() &&
"unexpected character type") ? void (0) : __assert_fail ("CharType->isIntegerType() && \"unexpected character type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3379, __extension__ __PRETTY_FUNCTION__))
;
3380
3381 APSInt Value(S->getCharByteWidth() * Info.Ctx.getCharWidth(),
3382 CharType->isUnsignedIntegerType());
3383 if (Index < S->getLength())
3384 Value = S->getCodeUnit(Index);
3385 return Value;
3386}
3387
3388// Expand a string literal into an array of characters.
3389//
3390// FIXME: This is inefficient; we should probably introduce something similar
3391// to the LLVM ConstantDataArray to make this cheaper.
3392static void expandStringLiteral(EvalInfo &Info, const StringLiteral *S,
3393 APValue &Result,
3394 QualType AllocType = QualType()) {
3395 const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(
3396 AllocType.isNull() ? S->getType() : AllocType);
3397 assert(CAT && "string literal isn't an array")(static_cast <bool> (CAT && "string literal isn't an array"
) ? void (0) : __assert_fail ("CAT && \"string literal isn't an array\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3397, __extension__ __PRETTY_FUNCTION__))
;
3398 QualType CharType = CAT->getElementType();
3399 assert(CharType->isIntegerType() && "unexpected character type")(static_cast <bool> (CharType->isIntegerType() &&
"unexpected character type") ? void (0) : __assert_fail ("CharType->isIntegerType() && \"unexpected character type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3399, __extension__ __PRETTY_FUNCTION__))
;
3400
3401 unsigned Elts = CAT->getSize().getZExtValue();
3402 Result = APValue(APValue::UninitArray(),
3403 std::min(S->getLength(), Elts), Elts);
3404 APSInt Value(S->getCharByteWidth() * Info.Ctx.getCharWidth(),
3405 CharType->isUnsignedIntegerType());
3406 if (Result.hasArrayFiller())
3407 Result.getArrayFiller() = APValue(Value);
3408 for (unsigned I = 0, N = Result.getArrayInitializedElts(); I != N; ++I) {
3409 Value = S->getCodeUnit(I);
3410 Result.getArrayInitializedElt(I) = APValue(Value);
3411 }
3412}
3413
3414// Expand an array so that it has more than Index filled elements.
3415static void expandArray(APValue &Array, unsigned Index) {
3416 unsigned Size = Array.getArraySize();
3417 assert(Index < Size)(static_cast <bool> (Index < Size) ? void (0) : __assert_fail
("Index < Size", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3417, __extension__ __PRETTY_FUNCTION__))
;
3418
3419 // Always at least double the number of elements for which we store a value.
3420 unsigned OldElts = Array.getArrayInitializedElts();
3421 unsigned NewElts = std::max(Index+1, OldElts * 2);
3422 NewElts = std::min(Size, std::max(NewElts, 8u));
3423
3424 // Copy the data across.
3425 APValue NewValue(APValue::UninitArray(), NewElts, Size);
3426 for (unsigned I = 0; I != OldElts; ++I)
3427 NewValue.getArrayInitializedElt(I).swap(Array.getArrayInitializedElt(I));
3428 for (unsigned I = OldElts; I != NewElts; ++I)
3429 NewValue.getArrayInitializedElt(I) = Array.getArrayFiller();
3430 if (NewValue.hasArrayFiller())
3431 NewValue.getArrayFiller() = Array.getArrayFiller();
3432 Array.swap(NewValue);
3433}
3434
3435/// Determine whether a type would actually be read by an lvalue-to-rvalue
3436/// conversion. If it's of class type, we may assume that the copy operation
3437/// is trivial. Note that this is never true for a union type with fields
3438/// (because the copy always "reads" the active member) and always true for
3439/// a non-class type.
3440static bool isReadByLvalueToRvalueConversion(const CXXRecordDecl *RD);
3441static bool isReadByLvalueToRvalueConversion(QualType T) {
3442 CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
3443 return !RD || isReadByLvalueToRvalueConversion(RD);
3444}
3445static bool isReadByLvalueToRvalueConversion(const CXXRecordDecl *RD) {
3446 // FIXME: A trivial copy of a union copies the object representation, even if
3447 // the union is empty.
3448 if (RD->isUnion())
3449 return !RD->field_empty();
3450 if (RD->isEmpty())
3451 return false;
3452
3453 for (auto *Field : RD->fields())
3454 if (!Field->isUnnamedBitfield() &&
3455 isReadByLvalueToRvalueConversion(Field->getType()))
3456 return true;
3457
3458 for (auto &BaseSpec : RD->bases())
3459 if (isReadByLvalueToRvalueConversion(BaseSpec.getType()))
3460 return true;
3461
3462 return false;
3463}
3464
3465/// Diagnose an attempt to read from any unreadable field within the specified
3466/// type, which might be a class type.
3467static bool diagnoseMutableFields(EvalInfo &Info, const Expr *E, AccessKinds AK,
3468 QualType T) {
3469 CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
3470 if (!RD)
3471 return false;
3472
3473 if (!RD->hasMutableFields())
3474 return false;
3475
3476 for (auto *Field : RD->fields()) {
3477 // If we're actually going to read this field in some way, then it can't
3478 // be mutable. If we're in a union, then assigning to a mutable field
3479 // (even an empty one) can change the active member, so that's not OK.
3480 // FIXME: Add core issue number for the union case.
3481 if (Field->isMutable() &&
3482 (RD->isUnion() || isReadByLvalueToRvalueConversion(Field->getType()))) {
3483 Info.FFDiag(E, diag::note_constexpr_access_mutable, 1) << AK << Field;
3484 Info.Note(Field->getLocation(), diag::note_declared_at);
3485 return true;
3486 }
3487
3488 if (diagnoseMutableFields(Info, E, AK, Field->getType()))
3489 return true;
3490 }
3491
3492 for (auto &BaseSpec : RD->bases())
3493 if (diagnoseMutableFields(Info, E, AK, BaseSpec.getType()))
3494 return true;
3495
3496 // All mutable fields were empty, and thus not actually read.
3497 return false;
3498}
3499
3500static bool lifetimeStartedInEvaluation(EvalInfo &Info,
3501 APValue::LValueBase Base,
3502 bool MutableSubobject = false) {
3503 // A temporary or transient heap allocation we created.
3504 if (Base.getCallIndex() || Base.is<DynamicAllocLValue>())
3505 return true;
3506
3507 switch (Info.IsEvaluatingDecl) {
3508 case EvalInfo::EvaluatingDeclKind::None:
3509 return false;
3510
3511 case EvalInfo::EvaluatingDeclKind::Ctor:
3512 // The variable whose initializer we're evaluating.
3513 if (Info.EvaluatingDecl == Base)
3514 return true;
3515
3516 // A temporary lifetime-extended by the variable whose initializer we're
3517 // evaluating.
3518 if (auto *BaseE = Base.dyn_cast<const Expr *>())
3519 if (auto *BaseMTE = dyn_cast<MaterializeTemporaryExpr>(BaseE))
3520 return Info.EvaluatingDecl == BaseMTE->getExtendingDecl();
3521 return false;
3522
3523 case EvalInfo::EvaluatingDeclKind::Dtor:
3524 // C++2a [expr.const]p6:
3525 // [during constant destruction] the lifetime of a and its non-mutable
3526 // subobjects (but not its mutable subobjects) [are] considered to start
3527 // within e.
3528 if (MutableSubobject || Base != Info.EvaluatingDecl)
3529 return false;
3530 // FIXME: We can meaningfully extend this to cover non-const objects, but
3531 // we will need special handling: we should be able to access only
3532 // subobjects of such objects that are themselves declared const.
3533 QualType T = getType(Base);
3534 return T.isConstQualified() || T->isReferenceType();
3535 }
3536
3537 llvm_unreachable("unknown evaluating decl kind")::llvm::llvm_unreachable_internal("unknown evaluating decl kind"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3537)
;
3538}
3539
3540namespace {
3541/// A handle to a complete object (an object that is not a subobject of
3542/// another object).
3543struct CompleteObject {
3544 /// The identity of the object.
3545 APValue::LValueBase Base;
3546 /// The value of the complete object.
3547 APValue *Value;
3548 /// The type of the complete object.
3549 QualType Type;
3550
3551 CompleteObject() : Value(nullptr) {}
3552 CompleteObject(APValue::LValueBase Base, APValue *Value, QualType Type)
3553 : Base(Base), Value(Value), Type(Type) {}
3554
3555 bool mayAccessMutableMembers(EvalInfo &Info, AccessKinds AK) const {
3556 // If this isn't a "real" access (eg, if it's just accessing the type
3557 // info), allow it. We assume the type doesn't change dynamically for
3558 // subobjects of constexpr objects (even though we'd hit UB here if it
3559 // did). FIXME: Is this right?
3560 if (!isAnyAccess(AK))
3561 return true;
3562
3563 // In C++14 onwards, it is permitted to read a mutable member whose
3564 // lifetime began within the evaluation.
3565 // FIXME: Should we also allow this in C++11?
3566 if (!Info.getLangOpts().CPlusPlus14)
3567 return false;
3568 return lifetimeStartedInEvaluation(Info, Base, /*MutableSubobject*/true);
3569 }
3570
3571 explicit operator bool() const { return !Type.isNull(); }
3572};
3573} // end anonymous namespace
3574
3575static QualType getSubobjectType(QualType ObjType, QualType SubobjType,
3576 bool IsMutable = false) {
3577 // C++ [basic.type.qualifier]p1:
3578 // - A const object is an object of type const T or a non-mutable subobject
3579 // of a const object.
3580 if (ObjType.isConstQualified() && !IsMutable)
3581 SubobjType.addConst();
3582 // - A volatile object is an object of type const T or a subobject of a
3583 // volatile object.
3584 if (ObjType.isVolatileQualified())
3585 SubobjType.addVolatile();
3586 return SubobjType;
3587}
3588
3589/// Find the designated sub-object of an rvalue.
3590template<typename SubobjectHandler>
3591typename SubobjectHandler::result_type
3592findSubobject(EvalInfo &Info, const Expr *E, const CompleteObject &Obj,
3593 const SubobjectDesignator &Sub, SubobjectHandler &handler) {
3594 if (Sub.Invalid)
3595 // A diagnostic will have already been produced.
3596 return handler.failed();
3597 if (Sub.isOnePastTheEnd() || Sub.isMostDerivedAnUnsizedArray()) {
3598 if (Info.getLangOpts().CPlusPlus11)
3599 Info.FFDiag(E, Sub.isOnePastTheEnd()
3600 ? diag::note_constexpr_access_past_end
3601 : diag::note_constexpr_access_unsized_array)
3602 << handler.AccessKind;
3603 else
3604 Info.FFDiag(E);
3605 return handler.failed();
3606 }
3607
3608 APValue *O = Obj.Value;
3609 QualType ObjType = Obj.Type;
3610 const FieldDecl *LastField = nullptr;
3611 const FieldDecl *VolatileField = nullptr;
3612
3613 // Walk the designator's path to find the subobject.
3614 for (unsigned I = 0, N = Sub.Entries.size(); /**/; ++I) {
3615 // Reading an indeterminate value is undefined, but assigning over one is OK.
3616 if ((O->isAbsent() && !(handler.AccessKind == AK_Construct && I == N)) ||
3617 (O->isIndeterminate() &&
3618 !isValidIndeterminateAccess(handler.AccessKind))) {
3619 if (!Info.checkingPotentialConstantExpression())
3620 Info.FFDiag(E, diag::note_constexpr_access_uninit)
3621 << handler.AccessKind << O->isIndeterminate();
3622 return handler.failed();
3623 }
3624
3625 // C++ [class.ctor]p5, C++ [class.dtor]p5:
3626 // const and volatile semantics are not applied on an object under
3627 // {con,de}struction.
3628 if ((ObjType.isConstQualified() || ObjType.isVolatileQualified()) &&
3629 ObjType->isRecordType() &&
3630 Info.isEvaluatingCtorDtor(
3631 Obj.Base, llvm::makeArrayRef(Sub.Entries.begin(),
3632 Sub.Entries.begin() + I)) !=
3633 ConstructionPhase::None) {
3634 ObjType = Info.Ctx.getCanonicalType(ObjType);
3635 ObjType.removeLocalConst();
3636 ObjType.removeLocalVolatile();
3637 }
3638
3639 // If this is our last pass, check that the final object type is OK.
3640 if (I == N || (I == N - 1 && ObjType->isAnyComplexType())) {
3641 // Accesses to volatile objects are prohibited.
3642 if (ObjType.isVolatileQualified() && isFormalAccess(handler.AccessKind)) {
3643 if (Info.getLangOpts().CPlusPlus) {
3644 int DiagKind;
3645 SourceLocation Loc;
3646 const NamedDecl *Decl = nullptr;
3647 if (VolatileField) {
3648 DiagKind = 2;
3649 Loc = VolatileField->getLocation();
3650 Decl = VolatileField;
3651 } else if (auto *VD = Obj.Base.dyn_cast<const ValueDecl*>()) {
3652 DiagKind = 1;
3653 Loc = VD->getLocation();
3654 Decl = VD;
3655 } else {
3656 DiagKind = 0;
3657 if (auto *E = Obj.Base.dyn_cast<const Expr *>())
3658 Loc = E->getExprLoc();
3659 }
3660 Info.FFDiag(E, diag::note_constexpr_access_volatile_obj, 1)
3661 << handler.AccessKind << DiagKind << Decl;
3662 Info.Note(Loc, diag::note_constexpr_volatile_here) << DiagKind;
3663 } else {
3664 Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
3665 }
3666 return handler.failed();
3667 }
3668
3669 // If we are reading an object of class type, there may still be more
3670 // things we need to check: if there are any mutable subobjects, we
3671 // cannot perform this read. (This only happens when performing a trivial
3672 // copy or assignment.)
3673 if (ObjType->isRecordType() &&
3674 !Obj.mayAccessMutableMembers(Info, handler.AccessKind) &&
3675 diagnoseMutableFields(Info, E, handler.AccessKind, ObjType))
3676 return handler.failed();
3677 }
3678
3679 if (I == N) {
3680 if (!handler.found(*O, ObjType))
3681 return false;
3682
3683 // If we modified a bit-field, truncate it to the right width.
3684 if (isModification(handler.AccessKind) &&
3685 LastField && LastField->isBitField() &&
3686 !truncateBitfieldValue(Info, E, *O, LastField))
3687 return false;
3688
3689 return true;
3690 }
3691
3692 LastField = nullptr;
3693 if (ObjType->isArrayType()) {
3694 // Next subobject is an array element.
3695 const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(ObjType);
3696 assert(CAT && "vla in literal type?")(static_cast <bool> (CAT && "vla in literal type?"
) ? void (0) : __assert_fail ("CAT && \"vla in literal type?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3696, __extension__ __PRETTY_FUNCTION__))
;
3697 uint64_t Index = Sub.Entries[I].getAsArrayIndex();
3698 if (CAT->getSize().ule(Index)) {
3699 // Note, it should not be possible to form a pointer with a valid
3700 // designator which points more than one past the end of the array.
3701 if (Info.getLangOpts().CPlusPlus11)
3702 Info.FFDiag(E, diag::note_constexpr_access_past_end)
3703 << handler.AccessKind;
3704 else
3705 Info.FFDiag(E);
3706 return handler.failed();
3707 }
3708
3709 ObjType = CAT->getElementType();
3710
3711 if (O->getArrayInitializedElts() > Index)
3712 O = &O->getArrayInitializedElt(Index);
3713 else if (!isRead(handler.AccessKind)) {
3714 expandArray(*O, Index);
3715 O = &O->getArrayInitializedElt(Index);
3716 } else
3717 O = &O->getArrayFiller();
3718 } else if (ObjType->isAnyComplexType()) {
3719 // Next subobject is a complex number.
3720 uint64_t Index = Sub.Entries[I].getAsArrayIndex();
3721 if (Index > 1) {
3722 if (Info.getLangOpts().CPlusPlus11)
3723 Info.FFDiag(E, diag::note_constexpr_access_past_end)
3724 << handler.AccessKind;
3725 else
3726 Info.FFDiag(E);
3727 return handler.failed();
3728 }
3729
3730 ObjType = getSubobjectType(
3731 ObjType, ObjType->castAs<ComplexType>()->getElementType());
3732
3733 assert(I == N - 1 && "extracting subobject of scalar?")(static_cast <bool> (I == N - 1 && "extracting subobject of scalar?"
) ? void (0) : __assert_fail ("I == N - 1 && \"extracting subobject of scalar?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3733, __extension__ __PRETTY_FUNCTION__))
;
3734 if (O->isComplexInt()) {
3735 return handler.found(Index ? O->getComplexIntImag()
3736 : O->getComplexIntReal(), ObjType);
3737 } else {
3738 assert(O->isComplexFloat())(static_cast <bool> (O->isComplexFloat()) ? void (0)
: __assert_fail ("O->isComplexFloat()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3738, __extension__ __PRETTY_FUNCTION__))
;
3739 return handler.found(Index ? O->getComplexFloatImag()
3740 : O->getComplexFloatReal(), ObjType);
3741 }
3742 } else if (const FieldDecl *Field = getAsField(Sub.Entries[I])) {
3743 if (Field->isMutable() &&
3744 !Obj.mayAccessMutableMembers(Info, handler.AccessKind)) {
3745 Info.FFDiag(E, diag::note_constexpr_access_mutable, 1)
3746 << handler.AccessKind << Field;
3747 Info.Note(Field->getLocation(), diag::note_declared_at);
3748 return handler.failed();
3749 }
3750
3751 // Next subobject is a class, struct or union field.
3752 RecordDecl *RD = ObjType->castAs<RecordType>()->getDecl();
3753 if (RD->isUnion()) {
3754 const FieldDecl *UnionField = O->getUnionField();
3755 if (!UnionField ||
3756 UnionField->getCanonicalDecl() != Field->getCanonicalDecl()) {
3757 if (I == N - 1 && handler.AccessKind == AK_Construct) {
3758 // Placement new onto an inactive union member makes it active.
3759 O->setUnion(Field, APValue());
3760 } else {
3761 // FIXME: If O->getUnionValue() is absent, report that there's no
3762 // active union member rather than reporting the prior active union
3763 // member. We'll need to fix nullptr_t to not use APValue() as its
3764 // representation first.
3765 Info.FFDiag(E, diag::note_constexpr_access_inactive_union_member)
3766 << handler.AccessKind << Field << !UnionField << UnionField;
3767 return handler.failed();
3768 }
3769 }
3770 O = &O->getUnionValue();
3771 } else
3772 O = &O->getStructField(Field->getFieldIndex());
3773
3774 ObjType = getSubobjectType(ObjType, Field->getType(), Field->isMutable());
3775 LastField = Field;
3776 if (Field->getType().isVolatileQualified())
3777 VolatileField = Field;
3778 } else {
3779 // Next subobject is a base class.
3780 const CXXRecordDecl *Derived = ObjType->getAsCXXRecordDecl();
3781 const CXXRecordDecl *Base = getAsBaseClass(Sub.Entries[I]);
3782 O = &O->getStructBase(getBaseIndex(Derived, Base));
3783
3784 ObjType = getSubobjectType(ObjType, Info.Ctx.getRecordType(Base));
3785 }
3786 }
3787}
3788
3789namespace {
3790struct ExtractSubobjectHandler {
3791 EvalInfo &Info;
3792 const Expr *E;
3793 APValue &Result;
3794 const AccessKinds AccessKind;
3795
3796 typedef bool result_type;
3797 bool failed() { return false; }
3798 bool found(APValue &Subobj, QualType SubobjType) {
3799 Result = Subobj;
3800 if (AccessKind == AK_ReadObjectRepresentation)
3801 return true;
3802 return CheckFullyInitialized(Info, E->getExprLoc(), SubobjType, Result);
3803 }
3804 bool found(APSInt &Value, QualType SubobjType) {
3805 Result = APValue(Value);
3806 return true;
3807 }
3808 bool found(APFloat &Value, QualType SubobjType) {
3809 Result = APValue(Value);
3810 return true;
3811 }
3812};
3813} // end anonymous namespace
3814
3815/// Extract the designated sub-object of an rvalue.
3816static bool extractSubobject(EvalInfo &Info, const Expr *E,
3817 const CompleteObject &Obj,
3818 const SubobjectDesignator &Sub, APValue &Result,
3819 AccessKinds AK = AK_Read) {
3820 assert(AK == AK_Read || AK == AK_ReadObjectRepresentation)(static_cast <bool> (AK == AK_Read || AK == AK_ReadObjectRepresentation
) ? void (0) : __assert_fail ("AK == AK_Read || AK == AK_ReadObjectRepresentation"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 3820, __extension__ __PRETTY_FUNCTION__))
;
3821 ExtractSubobjectHandler Handler = {Info, E, Result, AK};
3822 return findSubobject(Info, E, Obj, Sub, Handler);
3823}
3824
3825namespace {
3826struct ModifySubobjectHandler {
3827 EvalInfo &Info;
3828 APValue &NewVal;
3829 const Expr *E;
3830
3831 typedef bool result_type;
3832 static const AccessKinds AccessKind = AK_Assign;
3833
3834 bool checkConst(QualType QT) {
3835 // Assigning to a const object has undefined behavior.
3836 if (QT.isConstQualified()) {
3837 Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT;
3838 return false;
3839 }
3840 return true;
3841 }
3842
3843 bool failed() { return false; }
3844 bool found(APValue &Subobj, QualType SubobjType) {
3845 if (!checkConst(SubobjType))
3846 return false;
3847 // We've been given ownership of NewVal, so just swap it in.
3848 Subobj.swap(NewVal);
3849 return true;
3850 }
3851 bool found(APSInt &Value, QualType SubobjType) {
3852 if (!checkConst(SubobjType))
3853 return false;
3854 if (!NewVal.isInt()) {
3855 // Maybe trying to write a cast pointer value into a complex?
3856 Info.FFDiag(E);
3857 return false;
3858 }
3859 Value = NewVal.getInt();
3860 return true;
3861 }
3862 bool found(APFloat &Value, QualType SubobjType) {
3863 if (!checkConst(SubobjType))
3864 return false;
3865 Value = NewVal.getFloat();
3866 return true;
3867 }
3868};
3869} // end anonymous namespace
3870
3871const AccessKinds ModifySubobjectHandler::AccessKind;
3872
3873/// Update the designated sub-object of an rvalue to the given value.
3874static bool modifySubobject(EvalInfo &Info, const Expr *E,
3875 const CompleteObject &Obj,
3876 const SubobjectDesignator &Sub,
3877 APValue &NewVal) {
3878 ModifySubobjectHandler Handler = { Info, NewVal, E };
3879 return findSubobject(Info, E, Obj, Sub, Handler);
3880}
3881
3882/// Find the position where two subobject designators diverge, or equivalently
3883/// the length of the common initial subsequence.
3884static unsigned FindDesignatorMismatch(QualType ObjType,
3885 const SubobjectDesignator &A,
3886 const SubobjectDesignator &B,
3887 bool &WasArrayIndex) {
3888 unsigned I = 0, N = std::min(A.Entries.size(), B.Entries.size());
3889 for (/**/; I != N; ++I) {
3890 if (!ObjType.isNull() &&
3891 (ObjType->isArrayType() || ObjType->isAnyComplexType())) {
3892 // Next subobject is an array element.
3893 if (A.Entries[I].getAsArrayIndex() != B.Entries[I].getAsArrayIndex()) {
3894 WasArrayIndex = true;
3895 return I;
3896 }
3897 if (ObjType->isAnyComplexType())
3898 ObjType = ObjType->castAs<ComplexType>()->getElementType();
3899 else
3900 ObjType = ObjType->castAsArrayTypeUnsafe()->getElementType();
3901 } else {
3902 if (A.Entries[I].getAsBaseOrMember() !=
3903 B.Entries[I].getAsBaseOrMember()) {
3904 WasArrayIndex = false;
3905 return I;
3906 }
3907 if (const FieldDecl *FD = getAsField(A.Entries[I]))
3908 // Next subobject is a field.
3909 ObjType = FD->getType();
3910 else
3911 // Next subobject is a base class.
3912 ObjType = QualType();
3913 }
3914 }
3915 WasArrayIndex = false;
3916 return I;
3917}
3918
3919/// Determine whether the given subobject designators refer to elements of the
3920/// same array object.
3921static bool AreElementsOfSameArray(QualType ObjType,
3922 const SubobjectDesignator &A,
3923 const SubobjectDesignator &B) {
3924 if (A.Entries.size() != B.Entries.size())
3925 return false;
3926
3927 bool IsArray = A.MostDerivedIsArrayElement;
3928 if (IsArray && A.MostDerivedPathLength != A.Entries.size())
3929 // A is a subobject of the array element.
3930 return false;
3931
3932 // If A (and B) designates an array element, the last entry will be the array
3933 // index. That doesn't have to match. Otherwise, we're in the 'implicit array
3934 // of length 1' case, and the entire path must match.
3935 bool WasArrayIndex;
3936 unsigned CommonLength = FindDesignatorMismatch(ObjType, A, B, WasArrayIndex);
3937 return CommonLength >= A.Entries.size() - IsArray;
3938}
3939
3940/// Find the complete object to which an LValue refers.
3941static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E,
3942 AccessKinds AK, const LValue &LVal,
3943 QualType LValType) {
3944 if (LVal.InvalidBase) {
3945 Info.FFDiag(E);
3946 return CompleteObject();
3947 }
3948
3949 if (!LVal.Base) {
3950 Info.FFDiag(E, diag::note_constexpr_access_null) << AK;
3951 return CompleteObject();
3952 }
3953
3954 CallStackFrame *Frame = nullptr;
3955 unsigned Depth = 0;
3956 if (LVal.getLValueCallIndex()) {
3957 std::tie(Frame, Depth) =
3958 Info.getCallFrameAndDepth(LVal.getLValueCallIndex());
3959 if (!Frame) {
3960 Info.FFDiag(E, diag::note_constexpr_lifetime_ended, 1)
3961 << AK << LVal.Base.is<const ValueDecl*>();
3962 NoteLValueLocation(Info, LVal.Base);
3963 return CompleteObject();
3964 }
3965 }
3966
3967 bool IsAccess = isAnyAccess(AK);
3968
3969 // C++11 DR1311: An lvalue-to-rvalue conversion on a volatile-qualified type
3970 // is not a constant expression (even if the object is non-volatile). We also
3971 // apply this rule to C++98, in order to conform to the expected 'volatile'
3972 // semantics.
3973 if (isFormalAccess(AK) && LValType.isVolatileQualified()) {
3974 if (Info.getLangOpts().CPlusPlus)
3975 Info.FFDiag(E, diag::note_constexpr_access_volatile_type)
3976 << AK << LValType;
3977 else
3978 Info.FFDiag(E);
3979 return CompleteObject();
3980 }
3981
3982 // Compute value storage location and type of base object.
3983 APValue *BaseVal = nullptr;
3984 QualType BaseType = getType(LVal.Base);
3985
3986 if (Info.getLangOpts().CPlusPlus14 && LVal.Base == Info.EvaluatingDecl &&
3987 lifetimeStartedInEvaluation(Info, LVal.Base)) {
3988 // This is the object whose initializer we're evaluating, so its lifetime
3989 // started in the current evaluation.
3990 BaseVal = Info.EvaluatingDeclValue;
3991 } else if (const ValueDecl *D = LVal.Base.dyn_cast<const ValueDecl *>()) {
3992 // Allow reading from a GUID declaration.
3993 if (auto *GD = dyn_cast<MSGuidDecl>(D)) {
3994 if (isModification(AK)) {
3995 // All the remaining cases do not permit modification of the object.
3996 Info.FFDiag(E, diag::note_constexpr_modify_global);
3997 return CompleteObject();
3998 }
3999 APValue &V = GD->getAsAPValue();
4000 if (V.isAbsent()) {
4001 Info.FFDiag(E, diag::note_constexpr_unsupported_layout)
4002 << GD->getType();
4003 return CompleteObject();
4004 }
4005 return CompleteObject(LVal.Base, &V, GD->getType());
4006 }
4007
4008 // Allow reading from template parameter objects.
4009 if (auto *TPO = dyn_cast<TemplateParamObjectDecl>(D)) {
4010 if (isModification(AK)) {
4011 Info.FFDiag(E, diag::note_constexpr_modify_global);
4012 return CompleteObject();
4013 }
4014 return CompleteObject(LVal.Base, const_cast<APValue *>(&TPO->getValue()),
4015 TPO->getType());
4016 }
4017
4018 // In C++98, const, non-volatile integers initialized with ICEs are ICEs.
4019 // In C++11, constexpr, non-volatile variables initialized with constant
4020 // expressions are constant expressions too. Inside constexpr functions,
4021 // parameters are constant expressions even if they're non-const.
4022 // In C++1y, objects local to a constant expression (those with a Frame) are
4023 // both readable and writable inside constant expressions.
4024 // In C, such things can also be folded, although they are not ICEs.
4025 const VarDecl *VD = dyn_cast<VarDecl>(D);
4026 if (VD) {
4027 if (const VarDecl *VDef = VD->getDefinition(Info.Ctx))
4028 VD = VDef;
4029 }
4030 if (!VD || VD->isInvalidDecl()) {
4031 Info.FFDiag(E);
4032 return CompleteObject();
4033 }
4034
4035 bool IsConstant = BaseType.isConstant(Info.Ctx);
4036
4037 // Unless we're looking at a local variable or argument in a constexpr call,
4038 // the variable we're reading must be const.
4039 if (!Frame) {
4040 if (IsAccess && isa<ParmVarDecl>(VD)) {
4041 // Access of a parameter that's not associated with a frame isn't going
4042 // to work out, but we can leave it to evaluateVarDeclInit to provide a
4043 // suitable diagnostic.
4044 } else if (Info.getLangOpts().CPlusPlus14 &&
4045 lifetimeStartedInEvaluation(Info, LVal.Base)) {
4046 // OK, we can read and modify an object if we're in the process of
4047 // evaluating its initializer, because its lifetime began in this
4048 // evaluation.
4049 } else if (isModification(AK)) {
4050 // All the remaining cases do not permit modification of the object.
4051 Info.FFDiag(E, diag::note_constexpr_modify_global);
4052 return CompleteObject();
4053 } else if (VD->isConstexpr()) {
4054 // OK, we can read this variable.
4055 } else if (BaseType->isIntegralOrEnumerationType()) {
4056 if (!IsConstant) {
4057 if (!IsAccess)
4058 return CompleteObject(LVal.getLValueBase(), nullptr, BaseType);
4059 if (Info.getLangOpts().CPlusPlus) {
4060 Info.FFDiag(E, diag::note_constexpr_ltor_non_const_int, 1) << VD;
4061 Info.Note(VD->getLocation(), diag::note_declared_at);
4062 } else {
4063 Info.FFDiag(E);
4064 }
4065 return CompleteObject();
4066 }
4067 } else if (!IsAccess) {
4068 return CompleteObject(LVal.getLValueBase(), nullptr, BaseType);
4069 } else if (IsConstant && Info.checkingPotentialConstantExpression() &&
4070 BaseType->isLiteralType(Info.Ctx) && !VD->hasDefinition()) {
4071 // This variable might end up being constexpr. Don't diagnose it yet.
4072 } else if (IsConstant) {
4073 // Keep evaluating to see what we can do. In particular, we support
4074 // folding of const floating-point types, in order to make static const
4075 // data members of such types (supported as an extension) more useful.
4076 if (Info.getLangOpts().CPlusPlus) {
4077 Info.CCEDiag(E, Info.getLangOpts().CPlusPlus11
4078 ? diag::note_constexpr_ltor_non_constexpr
4079 : diag::note_constexpr_ltor_non_integral, 1)
4080 << VD << BaseType;
4081 Info.Note(VD->getLocation(), diag::note_declared_at);
4082 } else {
4083 Info.CCEDiag(E);
4084 }
4085 } else {
4086 // Never allow reading a non-const value.
4087 if (Info.getLangOpts().CPlusPlus) {
4088 Info.FFDiag(E, Info.getLangOpts().CPlusPlus11
4089 ? diag::note_constexpr_ltor_non_constexpr
4090 : diag::note_constexpr_ltor_non_integral, 1)
4091 << VD << BaseType;
4092 Info.Note(VD->getLocation(), diag::note_declared_at);
4093 } else {
4094 Info.FFDiag(E);
4095 }
4096 return CompleteObject();
4097 }
4098 }
4099
4100 if (!evaluateVarDeclInit(Info, E, VD, Frame, LVal.getLValueVersion(), BaseVal))
4101 return CompleteObject();
4102 } else if (DynamicAllocLValue DA = LVal.Base.dyn_cast<DynamicAllocLValue>()) {
4103 Optional<DynAlloc*> Alloc = Info.lookupDynamicAlloc(DA);
4104 if (!Alloc) {
4105 Info.FFDiag(E, diag::note_constexpr_access_deleted_object) << AK;
4106 return CompleteObject();
4107 }
4108 return CompleteObject(LVal.Base, &(*Alloc)->Value,
4109 LVal.Base.getDynamicAllocType());
4110 } else {
4111 const Expr *Base = LVal.Base.dyn_cast<const Expr*>();
4112
4113 if (!Frame) {
4114 if (const MaterializeTemporaryExpr *MTE =
4115 dyn_cast_or_null<MaterializeTemporaryExpr>(Base)) {
4116 assert(MTE->getStorageDuration() == SD_Static &&(static_cast <bool> (MTE->getStorageDuration() == SD_Static
&& "should have a frame for a non-global materialized temporary"
) ? void (0) : __assert_fail ("MTE->getStorageDuration() == SD_Static && \"should have a frame for a non-global materialized temporary\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4117, __extension__ __PRETTY_FUNCTION__))
4117 "should have a frame for a non-global materialized temporary")(static_cast <bool> (MTE->getStorageDuration() == SD_Static
&& "should have a frame for a non-global materialized temporary"
) ? void (0) : __assert_fail ("MTE->getStorageDuration() == SD_Static && \"should have a frame for a non-global materialized temporary\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4117, __extension__ __PRETTY_FUNCTION__))
;
4118
4119 // C++20 [expr.const]p4: [DR2126]
4120 // An object or reference is usable in constant expressions if it is
4121 // - a temporary object of non-volatile const-qualified literal type
4122 // whose lifetime is extended to that of a variable that is usable
4123 // in constant expressions
4124 //
4125 // C++20 [expr.const]p5:
4126 // an lvalue-to-rvalue conversion [is not allowed unless it applies to]
4127 // - a non-volatile glvalue that refers to an object that is usable
4128 // in constant expressions, or
4129 // - a non-volatile glvalue of literal type that refers to a
4130 // non-volatile object whose lifetime began within the evaluation
4131 // of E;
4132 //
4133 // C++11 misses the 'began within the evaluation of e' check and
4134 // instead allows all temporaries, including things like:
4135 // int &&r = 1;
4136 // int x = ++r;
4137 // constexpr int k = r;
4138 // Therefore we use the C++14-onwards rules in C++11 too.
4139 //
4140 // Note that temporaries whose lifetimes began while evaluating a
4141 // variable's constructor are not usable while evaluating the
4142 // corresponding destructor, not even if they're of const-qualified
4143 // types.
4144 if (!MTE->isUsableInConstantExpressions(Info.Ctx) &&
4145 !lifetimeStartedInEvaluation(Info, LVal.Base)) {
4146 if (!IsAccess)
4147 return CompleteObject(LVal.getLValueBase(), nullptr, BaseType);
4148 Info.FFDiag(E, diag::note_constexpr_access_static_temporary, 1) << AK;
4149 Info.Note(MTE->getExprLoc(), diag::note_constexpr_temporary_here);
4150 return CompleteObject();
4151 }
4152
4153 BaseVal = MTE->getOrCreateValue(false);
4154 assert(BaseVal && "got reference to unevaluated temporary")(static_cast <bool> (BaseVal && "got reference to unevaluated temporary"
) ? void (0) : __assert_fail ("BaseVal && \"got reference to unevaluated temporary\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4154, __extension__ __PRETTY_FUNCTION__))
;
4155 } else {
4156 if (!IsAccess)
4157 return CompleteObject(LVal.getLValueBase(), nullptr, BaseType);
4158 APValue Val;
4159 LVal.moveInto(Val);
4160 Info.FFDiag(E, diag::note_constexpr_access_unreadable_object)
4161 << AK
4162 << Val.getAsString(Info.Ctx,
4163 Info.Ctx.getLValueReferenceType(LValType));
4164 NoteLValueLocation(Info, LVal.Base);
4165 return CompleteObject();
4166 }
4167 } else {
4168 BaseVal = Frame->getTemporary(Base, LVal.Base.getVersion());
4169 assert(BaseVal && "missing value for temporary")(static_cast <bool> (BaseVal && "missing value for temporary"
) ? void (0) : __assert_fail ("BaseVal && \"missing value for temporary\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4169, __extension__ __PRETTY_FUNCTION__))
;
4170 }
4171 }
4172
4173 // In C++14, we can't safely access any mutable state when we might be
4174 // evaluating after an unmodeled side effect. Parameters are modeled as state
4175 // in the caller, but aren't visible once the call returns, so they can be
4176 // modified in a speculatively-evaluated call.
4177 //
4178 // FIXME: Not all local state is mutable. Allow local constant subobjects
4179 // to be read here (but take care with 'mutable' fields).
4180 unsigned VisibleDepth = Depth;
4181 if (llvm::isa_and_nonnull<ParmVarDecl>(
4182 LVal.Base.dyn_cast<const ValueDecl *>()))
4183 ++VisibleDepth;
4184 if ((Frame && Info.getLangOpts().CPlusPlus14 &&
4185 Info.EvalStatus.HasSideEffects) ||
4186 (isModification(AK) && VisibleDepth < Info.SpeculativeEvaluationDepth))
4187 return CompleteObject();
4188
4189 return CompleteObject(LVal.getLValueBase(), BaseVal, BaseType);
4190}
4191
4192/// Perform an lvalue-to-rvalue conversion on the given glvalue. This
4193/// can also be used for 'lvalue-to-lvalue' conversions for looking up the
4194/// glvalue referred to by an entity of reference type.
4195///
4196/// \param Info - Information about the ongoing evaluation.
4197/// \param Conv - The expression for which we are performing the conversion.
4198/// Used for diagnostics.
4199/// \param Type - The type of the glvalue (before stripping cv-qualifiers in the
4200/// case of a non-class type).
4201/// \param LVal - The glvalue on which we are attempting to perform this action.
4202/// \param RVal - The produced value will be placed here.
4203/// \param WantObjectRepresentation - If true, we're looking for the object
4204/// representation rather than the value, and in particular,
4205/// there is no requirement that the result be fully initialized.
4206static bool
4207handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv, QualType Type,
4208 const LValue &LVal, APValue &RVal,
4209 bool WantObjectRepresentation = false) {
4210 if (LVal.Designator.Invalid)
4211 return false;
4212
4213 // Check for special cases where there is no existing APValue to look at.
4214 const Expr *Base = LVal.Base.dyn_cast<const Expr*>();
4215
4216 AccessKinds AK =
4217 WantObjectRepresentation ? AK_ReadObjectRepresentation : AK_Read;
4218
4219 if (Base && !LVal.getLValueCallIndex() && !Type.isVolatileQualified()) {
4220 if (const CompoundLiteralExpr *CLE = dyn_cast<CompoundLiteralExpr>(Base)) {
4221 // In C99, a CompoundLiteralExpr is an lvalue, and we defer evaluating the
4222 // initializer until now for such expressions. Such an expression can't be
4223 // an ICE in C, so this only matters for fold.
4224 if (Type.isVolatileQualified()) {
4225 Info.FFDiag(Conv);
4226 return false;
4227 }
4228 APValue Lit;
4229 if (!Evaluate(Lit, Info, CLE->getInitializer()))
4230 return false;
4231 CompleteObject LitObj(LVal.Base, &Lit, Base->getType());
4232 return extractSubobject(Info, Conv, LitObj, LVal.Designator, RVal, AK);
4233 } else if (isa<StringLiteral>(Base) || isa<PredefinedExpr>(Base)) {
4234 // Special-case character extraction so we don't have to construct an
4235 // APValue for the whole string.
4236 assert(LVal.Designator.Entries.size() <= 1 &&(static_cast <bool> (LVal.Designator.Entries.size() <=
1 && "Can only read characters from string literals"
) ? void (0) : __assert_fail ("LVal.Designator.Entries.size() <= 1 && \"Can only read characters from string literals\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4237, __extension__ __PRETTY_FUNCTION__))
4237 "Can only read characters from string literals")(static_cast <bool> (LVal.Designator.Entries.size() <=
1 && "Can only read characters from string literals"
) ? void (0) : __assert_fail ("LVal.Designator.Entries.size() <= 1 && \"Can only read characters from string literals\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4237, __extension__ __PRETTY_FUNCTION__))
;
4238 if (LVal.Designator.Entries.empty()) {
4239 // Fail for now for LValue to RValue conversion of an array.
4240 // (This shouldn't show up in C/C++, but it could be triggered by a
4241 // weird EvaluateAsRValue call from a tool.)
4242 Info.FFDiag(Conv);
4243 return false;
4244 }
4245 if (LVal.Designator.isOnePastTheEnd()) {
4246 if (Info.getLangOpts().CPlusPlus11)
4247 Info.FFDiag(Conv, diag::note_constexpr_access_past_end) << AK;
4248 else
4249 Info.FFDiag(Conv);
4250 return false;
4251 }
4252 uint64_t CharIndex = LVal.Designator.Entries[0].getAsArrayIndex();
4253 RVal = APValue(extractStringLiteralCharacter(Info, Base, CharIndex));
4254 return true;
4255 }
4256 }
4257
4258 CompleteObject Obj = findCompleteObject(Info, Conv, AK, LVal, Type);
4259 return Obj && extractSubobject(Info, Conv, Obj, LVal.Designator, RVal, AK);
4260}
4261
4262/// Perform an assignment of Val to LVal. Takes ownership of Val.
4263static bool handleAssignment(EvalInfo &Info, const Expr *E, const LValue &LVal,
4264 QualType LValType, APValue &Val) {
4265 if (LVal.Designator.Invalid)
4266 return false;
4267
4268 if (!Info.getLangOpts().CPlusPlus14) {
4269 Info.FFDiag(E);
4270 return false;
4271 }
4272
4273 CompleteObject Obj = findCompleteObject(Info, E, AK_Assign, LVal, LValType);
4274 return Obj && modifySubobject(Info, E, Obj, LVal.Designator, Val);
4275}
4276
4277namespace {
4278struct CompoundAssignSubobjectHandler {
4279 EvalInfo &Info;
4280 const CompoundAssignOperator *E;
4281 QualType PromotedLHSType;
4282 BinaryOperatorKind Opcode;
4283 const APValue &RHS;
4284
4285 static const AccessKinds AccessKind = AK_Assign;
4286
4287 typedef bool result_type;
4288
4289 bool checkConst(QualType QT) {
4290 // Assigning to a const object has undefined behavior.
4291 if (QT.isConstQualified()) {
4292 Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT;
4293 return false;
4294 }
4295 return true;
4296 }
4297
4298 bool failed() { return false; }
4299 bool found(APValue &Subobj, QualType SubobjType) {
4300 switch (Subobj.getKind()) {
4301 case APValue::Int:
4302 return found(Subobj.getInt(), SubobjType);
4303 case APValue::Float:
4304 return found(Subobj.getFloat(), SubobjType);
4305 case APValue::ComplexInt:
4306 case APValue::ComplexFloat:
4307 // FIXME: Implement complex compound assignment.
4308 Info.FFDiag(E);
4309 return false;
4310 case APValue::LValue:
4311 return foundPointer(Subobj, SubobjType);
4312 case APValue::Vector:
4313 return foundVector(Subobj, SubobjType);
4314 default:
4315 // FIXME: can this happen?
4316 Info.FFDiag(E);
4317 return false;
4318 }
4319 }
4320
4321 bool foundVector(APValue &Value, QualType SubobjType) {
4322 if (!checkConst(SubobjType))
4323 return false;
4324
4325 if (!SubobjType->isVectorType()) {
4326 Info.FFDiag(E);
4327 return false;
4328 }
4329 return handleVectorVectorBinOp(Info, E, Opcode, Value, RHS);
4330 }
4331
4332 bool found(APSInt &Value, QualType SubobjType) {
4333 if (!checkConst(SubobjType))
4334 return false;
4335
4336 if (!SubobjType->isIntegerType()) {
4337 // We don't support compound assignment on integer-cast-to-pointer
4338 // values.
4339 Info.FFDiag(E);
4340 return false;
4341 }
4342
4343 if (RHS.isInt()) {
4344 APSInt LHS =
4345 HandleIntToIntCast(Info, E, PromotedLHSType, SubobjType, Value);
4346 if (!handleIntIntBinOp(Info, E, LHS, Opcode, RHS.getInt(), LHS))
4347 return false;
4348 Value = HandleIntToIntCast(Info, E, SubobjType, PromotedLHSType, LHS);
4349 return true;
4350 } else if (RHS.isFloat()) {
4351 const FPOptions FPO = E->getFPFeaturesInEffect(
4352 Info.Ctx.getLangOpts());
4353 APFloat FValue(0.0);
4354 return HandleIntToFloatCast(Info, E, FPO, SubobjType, Value,
4355 PromotedLHSType, FValue) &&
4356 handleFloatFloatBinOp(Info, E, FValue, Opcode, RHS.getFloat()) &&
4357 HandleFloatToIntCast(Info, E, PromotedLHSType, FValue, SubobjType,
4358 Value);
4359 }
4360
4361 Info.FFDiag(E);
4362 return false;
4363 }
4364 bool found(APFloat &Value, QualType SubobjType) {
4365 return checkConst(SubobjType) &&
4366 HandleFloatToFloatCast(Info, E, SubobjType, PromotedLHSType,
4367 Value) &&
4368 handleFloatFloatBinOp(Info, E, Value, Opcode, RHS.getFloat()) &&
4369 HandleFloatToFloatCast(Info, E, PromotedLHSType, SubobjType, Value);
4370 }
4371 bool foundPointer(APValue &Subobj, QualType SubobjType) {
4372 if (!checkConst(SubobjType))
4373 return false;
4374
4375 QualType PointeeType;
4376 if (const PointerType *PT = SubobjType->getAs<PointerType>())
4377 PointeeType = PT->getPointeeType();
4378
4379 if (PointeeType.isNull() || !RHS.isInt() ||
4380 (Opcode != BO_Add && Opcode != BO_Sub)) {
4381 Info.FFDiag(E);
4382 return false;
4383 }
4384
4385 APSInt Offset = RHS.getInt();
4386 if (Opcode == BO_Sub)
4387 negateAsSigned(Offset);
4388
4389 LValue LVal;
4390 LVal.setFrom(Info.Ctx, Subobj);
4391 if (!HandleLValueArrayAdjustment(Info, E, LVal, PointeeType, Offset))
4392 return false;
4393 LVal.moveInto(Subobj);
4394 return true;
4395 }
4396};
4397} // end anonymous namespace
4398
4399const AccessKinds CompoundAssignSubobjectHandler::AccessKind;
4400
4401/// Perform a compound assignment of LVal <op>= RVal.
4402static bool handleCompoundAssignment(EvalInfo &Info,
4403 const CompoundAssignOperator *E,
4404 const LValue &LVal, QualType LValType,
4405 QualType PromotedLValType,
4406 BinaryOperatorKind Opcode,
4407 const APValue &RVal) {
4408 if (LVal.Designator.Invalid)
4409 return false;
4410
4411 if (!Info.getLangOpts().CPlusPlus14) {
4412 Info.FFDiag(E);
4413 return false;
4414 }
4415
4416 CompleteObject Obj = findCompleteObject(Info, E, AK_Assign, LVal, LValType);
4417 CompoundAssignSubobjectHandler Handler = { Info, E, PromotedLValType, Opcode,
4418 RVal };
4419 return Obj && findSubobject(Info, E, Obj, LVal.Designator, Handler);
4420}
4421
4422namespace {
4423struct IncDecSubobjectHandler {
4424 EvalInfo &Info;
4425 const UnaryOperator *E;
4426 AccessKinds AccessKind;
4427 APValue *Old;
4428
4429 typedef bool result_type;
4430
4431 bool checkConst(QualType QT) {
4432 // Assigning to a const object has undefined behavior.
4433 if (QT.isConstQualified()) {
4434 Info.FFDiag(E, diag::note_constexpr_modify_const_type) << QT;
4435 return false;
4436 }
4437 return true;
4438 }
4439
4440 bool failed() { return false; }
4441 bool found(APValue &Subobj, QualType SubobjType) {
4442 // Stash the old value. Also clear Old, so we don't clobber it later
4443 // if we're post-incrementing a complex.
4444 if (Old) {
4445 *Old = Subobj;
4446 Old = nullptr;
4447 }
4448
4449 switch (Subobj.getKind()) {
4450 case APValue::Int:
4451 return found(Subobj.getInt(), SubobjType);
4452 case APValue::Float:
4453 return found(Subobj.getFloat(), SubobjType);
4454 case APValue::ComplexInt:
4455 return found(Subobj.getComplexIntReal(),
4456 SubobjType->castAs<ComplexType>()->getElementType()
4457 .withCVRQualifiers(SubobjType.getCVRQualifiers()));
4458 case APValue::ComplexFloat:
4459 return found(Subobj.getComplexFloatReal(),
4460 SubobjType->castAs<ComplexType>()->getElementType()
4461 .withCVRQualifiers(SubobjType.getCVRQualifiers()));
4462 case APValue::LValue:
4463 return foundPointer(Subobj, SubobjType);
4464 default:
4465 // FIXME: can this happen?
4466 Info.FFDiag(E);
4467 return false;
4468 }
4469 }
4470 bool found(APSInt &Value, QualType SubobjType) {
4471 if (!checkConst(SubobjType))
4472 return false;
4473
4474 if (!SubobjType->isIntegerType()) {
4475 // We don't support increment / decrement on integer-cast-to-pointer
4476 // values.
4477 Info.FFDiag(E);
4478 return false;
4479 }
4480
4481 if (Old) *Old = APValue(Value);
4482
4483 // bool arithmetic promotes to int, and the conversion back to bool
4484 // doesn't reduce mod 2^n, so special-case it.
4485 if (SubobjType->isBooleanType()) {
4486 if (AccessKind == AK_Increment)
4487 Value = 1;
4488 else
4489 Value = !Value;
4490 return true;
4491 }
4492
4493 bool WasNegative = Value.isNegative();
4494 if (AccessKind == AK_Increment) {
4495 ++Value;
4496
4497 if (!WasNegative && Value.isNegative() && E->canOverflow()) {
4498 APSInt ActualValue(Value, /*IsUnsigned*/true);
4499 return HandleOverflow(Info, E, ActualValue, SubobjType);
4500 }
4501 } else {
4502 --Value;
4503
4504 if (WasNegative && !Value.isNegative() && E->canOverflow()) {
4505 unsigned BitWidth = Value.getBitWidth();
4506 APSInt ActualValue(Value.sext(BitWidth + 1), /*IsUnsigned*/false);
4507 ActualValue.setBit(BitWidth);
4508 return HandleOverflow(Info, E, ActualValue, SubobjType);
4509 }
4510 }
4511 return true;
4512 }
4513 bool found(APFloat &Value, QualType SubobjType) {
4514 if (!checkConst(SubobjType))
4515 return false;
4516
4517 if (Old) *Old = APValue(Value);
4518
4519 APFloat One(Value.getSemantics(), 1);
4520 if (AccessKind == AK_Increment)
4521 Value.add(One, APFloat::rmNearestTiesToEven);
4522 else
4523 Value.subtract(One, APFloat::rmNearestTiesToEven);
4524 return true;
4525 }
4526 bool foundPointer(APValue &Subobj, QualType SubobjType) {
4527 if (!checkConst(SubobjType))
4528 return false;
4529
4530 QualType PointeeType;
4531 if (const PointerType *PT = SubobjType->getAs<PointerType>())
4532 PointeeType = PT->getPointeeType();
4533 else {
4534 Info.FFDiag(E);
4535 return false;
4536 }
4537
4538 LValue LVal;
4539 LVal.setFrom(Info.Ctx, Subobj);
4540 if (!HandleLValueArrayAdjustment(Info, E, LVal, PointeeType,
4541 AccessKind == AK_Increment ? 1 : -1))
4542 return false;
4543 LVal.moveInto(Subobj);
4544 return true;
4545 }
4546};
4547} // end anonymous namespace
4548
4549/// Perform an increment or decrement on LVal.
4550static bool handleIncDec(EvalInfo &Info, const Expr *E, const LValue &LVal,
4551 QualType LValType, bool IsIncrement, APValue *Old) {
4552 if (LVal.Designator.Invalid)
4553 return false;
4554
4555 if (!Info.getLangOpts().CPlusPlus14) {
4556 Info.FFDiag(E);
4557 return false;
4558 }
4559
4560 AccessKinds AK = IsIncrement ? AK_Increment : AK_Decrement;
4561 CompleteObject Obj = findCompleteObject(Info, E, AK, LVal, LValType);
4562 IncDecSubobjectHandler Handler = {Info, cast<UnaryOperator>(E), AK, Old};
4563 return Obj && findSubobject(Info, E, Obj, LVal.Designator, Handler);
4564}
4565
4566/// Build an lvalue for the object argument of a member function call.
4567static bool EvaluateObjectArgument(EvalInfo &Info, const Expr *Object,
4568 LValue &This) {
4569 if (Object->getType()->isPointerType() && Object->isPRValue())
4570 return EvaluatePointer(Object, This, Info);
4571
4572 if (Object->isGLValue())
4573 return EvaluateLValue(Object, This, Info);
4574
4575 if (Object->getType()->isLiteralType(Info.Ctx))
4576 return EvaluateTemporary(Object, This, Info);
4577
4578 Info.FFDiag(Object, diag::note_constexpr_nonliteral) << Object->getType();
4579 return false;
4580}
4581
4582/// HandleMemberPointerAccess - Evaluate a member access operation and build an
4583/// lvalue referring to the result.
4584///
4585/// \param Info - Information about the ongoing evaluation.
4586/// \param LV - An lvalue referring to the base of the member pointer.
4587/// \param RHS - The member pointer expression.
4588/// \param IncludeMember - Specifies whether the member itself is included in
4589/// the resulting LValue subobject designator. This is not possible when
4590/// creating a bound member function.
4591/// \return The field or method declaration to which the member pointer refers,
4592/// or 0 if evaluation fails.
4593static const ValueDecl *HandleMemberPointerAccess(EvalInfo &Info,
4594 QualType LVType,
4595 LValue &LV,
4596 const Expr *RHS,
4597 bool IncludeMember = true) {
4598 MemberPtr MemPtr;
4599 if (!EvaluateMemberPointer(RHS, MemPtr, Info))
4600 return nullptr;
4601
4602 // C++11 [expr.mptr.oper]p6: If the second operand is the null pointer to
4603 // member value, the behavior is undefined.
4604 if (!MemPtr.getDecl()) {
4605 // FIXME: Specific diagnostic.
4606 Info.FFDiag(RHS);
4607 return nullptr;
4608 }
4609
4610 if (MemPtr.isDerivedMember()) {
4611 // This is a member of some derived class. Truncate LV appropriately.
4612 // The end of the derived-to-base path for the base object must match the
4613 // derived-to-base path for the member pointer.
4614 if (LV.Designator.MostDerivedPathLength + MemPtr.Path.size() >
4615 LV.Designator.Entries.size()) {
4616 Info.FFDiag(RHS);
4617 return nullptr;
4618 }
4619 unsigned PathLengthToMember =
4620 LV.Designator.Entries.size() - MemPtr.Path.size();
4621 for (unsigned I = 0, N = MemPtr.Path.size(); I != N; ++I) {
4622 const CXXRecordDecl *LVDecl = getAsBaseClass(
4623 LV.Designator.Entries[PathLengthToMember + I]);
4624 const CXXRecordDecl *MPDecl = MemPtr.Path[I];
4625 if (LVDecl->getCanonicalDecl() != MPDecl->getCanonicalDecl()) {
4626 Info.FFDiag(RHS);
4627 return nullptr;
4628 }
4629 }
4630
4631 // Truncate the lvalue to the appropriate derived class.
4632 if (!CastToDerivedClass(Info, RHS, LV, MemPtr.getContainingRecord(),
4633 PathLengthToMember))
4634 return nullptr;
4635 } else if (!MemPtr.Path.empty()) {
4636 // Extend the LValue path with the member pointer's path.
4637 LV.Designator.Entries.reserve(LV.Designator.Entries.size() +
4638 MemPtr.Path.size() + IncludeMember);
4639
4640 // Walk down to the appropriate base class.
4641 if (const PointerType *PT = LVType->getAs<PointerType>())
4642 LVType = PT->getPointeeType();
4643 const CXXRecordDecl *RD = LVType->getAsCXXRecordDecl();
4644 assert(RD && "member pointer access on non-class-type expression")(static_cast <bool> (RD && "member pointer access on non-class-type expression"
) ? void (0) : __assert_fail ("RD && \"member pointer access on non-class-type expression\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4644, __extension__ __PRETTY_FUNCTION__))
;
4645 // The first class in the path is that of the lvalue.
4646 for (unsigned I = 1, N = MemPtr.Path.size(); I != N; ++I) {
4647 const CXXRecordDecl *Base = MemPtr.Path[N - I - 1];
4648 if (!HandleLValueDirectBase(Info, RHS, LV, RD, Base))
4649 return nullptr;
4650 RD = Base;
4651 }
4652 // Finally cast to the class containing the member.
4653 if (!HandleLValueDirectBase(Info, RHS, LV, RD,
4654 MemPtr.getContainingRecord()))
4655 return nullptr;
4656 }
4657
4658 // Add the member. Note that we cannot build bound member functions here.
4659 if (IncludeMember) {
4660 if (const FieldDecl *FD = dyn_cast<FieldDecl>(MemPtr.getDecl())) {
4661 if (!HandleLValueMember(Info, RHS, LV, FD))
4662 return nullptr;
4663 } else if (const IndirectFieldDecl *IFD =
4664 dyn_cast<IndirectFieldDecl>(MemPtr.getDecl())) {
4665 if (!HandleLValueIndirectMember(Info, RHS, LV, IFD))
4666 return nullptr;
4667 } else {
4668 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-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4668)
;
4669 }
4670 }
4671
4672 return MemPtr.getDecl();
4673}
4674
4675static const ValueDecl *HandleMemberPointerAccess(EvalInfo &Info,
4676 const BinaryOperator *BO,
4677 LValue &LV,
4678 bool IncludeMember = true) {
4679 assert(BO->getOpcode() == BO_PtrMemD || BO->getOpcode() == BO_PtrMemI)(static_cast <bool> (BO->getOpcode() == BO_PtrMemD ||
BO->getOpcode() == BO_PtrMemI) ? void (0) : __assert_fail
("BO->getOpcode() == BO_PtrMemD || BO->getOpcode() == BO_PtrMemI"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4679, __extension__ __PRETTY_FUNCTION__))
;
4680
4681 if (!EvaluateObjectArgument(Info, BO->getLHS(), LV)) {
4682 if (Info.noteFailure()) {
4683 MemberPtr MemPtr;
4684 EvaluateMemberPointer(BO->getRHS(), MemPtr, Info);
4685 }
4686 return nullptr;
4687 }
4688
4689 return HandleMemberPointerAccess(Info, BO->getLHS()->getType(), LV,
4690 BO->getRHS(), IncludeMember);
4691}
4692
4693/// HandleBaseToDerivedCast - Apply the given base-to-derived cast operation on
4694/// the provided lvalue, which currently refers to the base object.
4695static bool HandleBaseToDerivedCast(EvalInfo &Info, const CastExpr *E,
4696 LValue &Result) {
4697 SubobjectDesignator &D = Result.Designator;
4698 if (D.Invalid || !Result.checkNullPointer(Info, E, CSK_Derived))
4699 return false;
4700
4701 QualType TargetQT = E->getType();
4702 if (const PointerType *PT = TargetQT->getAs<PointerType>())
4703 TargetQT = PT->getPointeeType();
4704
4705 // Check this cast lands within the final derived-to-base subobject path.
4706 if (D.MostDerivedPathLength + E->path_size() > D.Entries.size()) {
4707 Info.CCEDiag(E, diag::note_constexpr_invalid_downcast)
4708 << D.MostDerivedType << TargetQT;
4709 return false;
4710 }
4711
4712 // Check the type of the final cast. We don't need to check the path,
4713 // since a cast can only be formed if the path is unique.
4714 unsigned NewEntriesSize = D.Entries.size() - E->path_size();
4715 const CXXRecordDecl *TargetType = TargetQT->getAsCXXRecordDecl();
4716 const CXXRecordDecl *FinalType;
4717 if (NewEntriesSize == D.MostDerivedPathLength)
4718 FinalType = D.MostDerivedType->getAsCXXRecordDecl();
4719 else
4720 FinalType = getAsBaseClass(D.Entries[NewEntriesSize - 1]);
4721 if (FinalType->getCanonicalDecl() != TargetType->getCanonicalDecl()) {
4722 Info.CCEDiag(E, diag::note_constexpr_invalid_downcast)
4723 << D.MostDerivedType << TargetQT;
4724 return false;
4725 }
4726
4727 // Truncate the lvalue to the appropriate derived class.
4728 return CastToDerivedClass(Info, E, Result, TargetType, NewEntriesSize);
4729}
4730
4731/// Get the value to use for a default-initialized object of type T.
4732/// Return false if it encounters something invalid.
4733static bool getDefaultInitValue(QualType T, APValue &Result) {
4734 bool Success = true;
4735 if (auto *RD = T->getAsCXXRecordDecl()) {
4736 if (RD->isInvalidDecl()) {
4737 Result = APValue();
4738 return false;
4739 }
4740 if (RD->isUnion()) {
4741 Result = APValue((const FieldDecl *)nullptr);
4742 return true;
4743 }
4744 Result = APValue(APValue::UninitStruct(), RD->getNumBases(),
4745 std::distance(RD->field_begin(), RD->field_end()));
4746
4747 unsigned Index = 0;
4748 for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
4749 End = RD->bases_end();
4750 I != End; ++I, ++Index)
4751 Success &= getDefaultInitValue(I->getType(), Result.getStructBase(Index));
4752
4753 for (const auto *I : RD->fields()) {
4754 if (I->isUnnamedBitfield())
4755 continue;
4756 Success &= getDefaultInitValue(I->getType(),
4757 Result.getStructField(I->getFieldIndex()));
4758 }
4759 return Success;
4760 }
4761
4762 if (auto *AT =
4763 dyn_cast_or_null<ConstantArrayType>(T->getAsArrayTypeUnsafe())) {
4764 Result = APValue(APValue::UninitArray(), 0, AT->getSize().getZExtValue());
4765 if (Result.hasArrayFiller())
4766 Success &=
4767 getDefaultInitValue(AT->getElementType(), Result.getArrayFiller());
4768
4769 return Success;
4770 }
4771
4772 Result = APValue::IndeterminateValue();
4773 return true;
4774}
4775
4776namespace {
4777enum EvalStmtResult {
4778 /// Evaluation failed.
4779 ESR_Failed,
4780 /// Hit a 'return' statement.
4781 ESR_Returned,
4782 /// Evaluation succeeded.
4783 ESR_Succeeded,
4784 /// Hit a 'continue' statement.
4785 ESR_Continue,
4786 /// Hit a 'break' statement.
4787 ESR_Break,
4788 /// Still scanning for 'case' or 'default' statement.
4789 ESR_CaseNotFound
4790};
4791}
4792
4793static bool EvaluateVarDecl(EvalInfo &Info, const VarDecl *VD) {
4794 // We don't need to evaluate the initializer for a static local.
4795 if (!VD->hasLocalStorage())
4796 return true;
4797
4798 LValue Result;
4799 APValue &Val = Info.CurrentCall->createTemporary(VD, VD->getType(),
4800 ScopeKind::Block, Result);
4801
4802 const Expr *InitE = VD->getInit();
4803 if (!InitE) {
4804 if (VD->getType()->isDependentType())
4805 return Info.noteSideEffect();
4806 return getDefaultInitValue(VD->getType(), Val);
4807 }
4808 if (InitE->isValueDependent())
4809 return false;
4810
4811 if (!EvaluateInPlace(Val, Info, Result, InitE)) {
4812 // Wipe out any partially-computed value, to allow tracking that this
4813 // evaluation failed.
4814 Val = APValue();
4815 return false;
4816 }
4817
4818 return true;
4819}
4820
4821static bool EvaluateDecl(EvalInfo &Info, const Decl *D) {
4822 bool OK = true;
4823
4824 if (const VarDecl *VD = dyn_cast<VarDecl>(D))
4825 OK &= EvaluateVarDecl(Info, VD);
4826
4827 if (const DecompositionDecl *DD = dyn_cast<DecompositionDecl>(D))
4828 for (auto *BD : DD->bindings())
4829 if (auto *VD = BD->getHoldingVar())
4830 OK &= EvaluateDecl(Info, VD);
4831
4832 return OK;
4833}
4834
4835static bool EvaluateDependentExpr(const Expr *E, EvalInfo &Info) {
4836 assert(E->isValueDependent())(static_cast <bool> (E->isValueDependent()) ? void (
0) : __assert_fail ("E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4836, __extension__ __PRETTY_FUNCTION__))
;
4837 if (Info.noteSideEffect())
4838 return true;
4839 assert(E->containsErrors() && "valid value-dependent expression should never "(static_cast <bool> (E->containsErrors() && "valid value-dependent expression should never "
"reach invalid code path.") ? void (0) : __assert_fail ("E->containsErrors() && \"valid value-dependent expression should never \" \"reach invalid code path.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4840, __extension__ __PRETTY_FUNCTION__))
4840 "reach invalid code path.")(static_cast <bool> (E->containsErrors() && "valid value-dependent expression should never "
"reach invalid code path.") ? void (0) : __assert_fail ("E->containsErrors() && \"valid value-dependent expression should never \" \"reach invalid code path.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4840, __extension__ __PRETTY_FUNCTION__))
;
4841 return false;
4842}
4843
4844/// Evaluate a condition (either a variable declaration or an expression).
4845static bool EvaluateCond(EvalInfo &Info, const VarDecl *CondDecl,
4846 const Expr *Cond, bool &Result) {
4847 if (Cond->isValueDependent())
4848 return false;
4849 FullExpressionRAII Scope(Info);
4850 if (CondDecl && !EvaluateDecl(Info, CondDecl))
4851 return false;
4852 if (!EvaluateAsBooleanCondition(Cond, Result, Info))
4853 return false;
4854 return Scope.destroy();
4855}
4856
4857namespace {
4858/// A location where the result (returned value) of evaluating a
4859/// statement should be stored.
4860struct StmtResult {
4861 /// The APValue that should be filled in with the returned value.
4862 APValue &Value;
4863 /// The location containing the result, if any (used to support RVO).
4864 const LValue *Slot;
4865};
4866
4867struct TempVersionRAII {
4868 CallStackFrame &Frame;
4869
4870 TempVersionRAII(CallStackFrame &Frame) : Frame(Frame) {
4871 Frame.pushTempVersion();
4872 }
4873
4874 ~TempVersionRAII() {
4875 Frame.popTempVersion();
4876 }
4877};
4878
4879}
4880
4881static EvalStmtResult EvaluateStmt(StmtResult &Result, EvalInfo &Info,
4882 const Stmt *S,
4883 const SwitchCase *SC = nullptr);
4884
4885/// Evaluate the body of a loop, and translate the result as appropriate.
4886static EvalStmtResult EvaluateLoopBody(StmtResult &Result, EvalInfo &Info,
4887 const Stmt *Body,
4888 const SwitchCase *Case = nullptr) {
4889 BlockScopeRAII Scope(Info);
4890
4891 EvalStmtResult ESR = EvaluateStmt(Result, Info, Body, Case);
4892 if (ESR != ESR_Failed && ESR != ESR_CaseNotFound && !Scope.destroy())
4893 ESR = ESR_Failed;
4894
4895 switch (ESR) {
4896 case ESR_Break:
4897 return ESR_Succeeded;
4898 case ESR_Succeeded:
4899 case ESR_Continue:
4900 return ESR_Continue;
4901 case ESR_Failed:
4902 case ESR_Returned:
4903 case ESR_CaseNotFound:
4904 return ESR;
4905 }
4906 llvm_unreachable("Invalid EvalStmtResult!")::llvm::llvm_unreachable_internal("Invalid EvalStmtResult!", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4906)
;
4907}
4908
4909/// Evaluate a switch statement.
4910static EvalStmtResult EvaluateSwitch(StmtResult &Result, EvalInfo &Info,
4911 const SwitchStmt *SS) {
4912 BlockScopeRAII Scope(Info);
4913
4914 // Evaluate the switch condition.
4915 APSInt Value;
4916 {
4917 if (const Stmt *Init = SS->getInit()) {
4918 EvalStmtResult ESR = EvaluateStmt(Result, Info, Init);
4919 if (ESR != ESR_Succeeded) {
4920 if (ESR != ESR_Failed && !Scope.destroy())
4921 ESR = ESR_Failed;
4922 return ESR;
4923 }
4924 }
4925
4926 FullExpressionRAII CondScope(Info);
4927 if (SS->getConditionVariable() &&
4928 !EvaluateDecl(Info, SS->getConditionVariable()))
4929 return ESR_Failed;
4930 if (!EvaluateInteger(SS->getCond(), Value, Info))
4931 return ESR_Failed;
4932 if (!CondScope.destroy())
4933 return ESR_Failed;
4934 }
4935
4936 // Find the switch case corresponding to the value of the condition.
4937 // FIXME: Cache this lookup.
4938 const SwitchCase *Found = nullptr;
4939 for (const SwitchCase *SC = SS->getSwitchCaseList(); SC;
4940 SC = SC->getNextSwitchCase()) {
4941 if (isa<DefaultStmt>(SC)) {
4942 Found = SC;
4943 continue;
4944 }
4945
4946 const CaseStmt *CS = cast<CaseStmt>(SC);
4947 APSInt LHS = CS->getLHS()->EvaluateKnownConstInt(Info.Ctx);
4948 APSInt RHS = CS->getRHS() ? CS->getRHS()->EvaluateKnownConstInt(Info.Ctx)
4949 : LHS;
4950 if (LHS <= Value && Value <= RHS) {
4951 Found = SC;
4952 break;
4953 }
4954 }
4955
4956 if (!Found)
4957 return Scope.destroy() ? ESR_Succeeded : ESR_Failed;
4958
4959 // Search the switch body for the switch case and evaluate it from there.
4960 EvalStmtResult ESR = EvaluateStmt(Result, Info, SS->getBody(), Found);
4961 if (ESR != ESR_Failed && ESR != ESR_CaseNotFound && !Scope.destroy())
4962 return ESR_Failed;
4963
4964 switch (ESR) {
4965 case ESR_Break:
4966 return ESR_Succeeded;
4967 case ESR_Succeeded:
4968 case ESR_Continue:
4969 case ESR_Failed:
4970 case ESR_Returned:
4971 return ESR;
4972 case ESR_CaseNotFound:
4973 // This can only happen if the switch case is nested within a statement
4974 // expression. We have no intention of supporting that.
4975 Info.FFDiag(Found->getBeginLoc(),
4976 diag::note_constexpr_stmt_expr_unsupported);
4977 return ESR_Failed;
4978 }
4979 llvm_unreachable("Invalid EvalStmtResult!")::llvm::llvm_unreachable_internal("Invalid EvalStmtResult!", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 4979)
;
4980}
4981
4982// Evaluate a statement.
4983static EvalStmtResult EvaluateStmt(StmtResult &Result, EvalInfo &Info,
4984 const Stmt *S, const SwitchCase *Case) {
4985 if (!Info.nextStep(S))
4986 return ESR_Failed;
4987
4988 // If we're hunting down a 'case' or 'default' label, recurse through
4989 // substatements until we hit the label.
4990 if (Case) {
4991 switch (S->getStmtClass()) {
4992 case Stmt::CompoundStmtClass:
4993 // FIXME: Precompute which substatement of a compound statement we
4994 // would jump to, and go straight there rather than performing a
4995 // linear scan each time.
4996 case Stmt::LabelStmtClass:
4997 case Stmt::AttributedStmtClass:
4998 case Stmt::DoStmtClass:
4999 break;
5000
5001 case Stmt::CaseStmtClass:
5002 case Stmt::DefaultStmtClass:
5003 if (Case == S)
5004 Case = nullptr;
5005 break;
5006
5007 case Stmt::IfStmtClass: {
5008 // FIXME: Precompute which side of an 'if' we would jump to, and go
5009 // straight there rather than scanning both sides.
5010 const IfStmt *IS = cast<IfStmt>(S);
5011
5012 // Wrap the evaluation in a block scope, in case it's a DeclStmt
5013 // preceded by our switch label.
5014 BlockScopeRAII Scope(Info);
5015
5016 // Step into the init statement in case it brings an (uninitialized)
5017 // variable into scope.
5018 if (const Stmt *Init = IS->getInit()) {
5019 EvalStmtResult ESR = EvaluateStmt(Result, Info, Init, Case);
5020 if (ESR != ESR_CaseNotFound) {
5021 assert(ESR != ESR_Succeeded)(static_cast <bool> (ESR != ESR_Succeeded) ? void (0) :
__assert_fail ("ESR != ESR_Succeeded", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5021, __extension__ __PRETTY_FUNCTION__))
;
5022 return ESR;
5023 }
5024 }
5025
5026 // Condition variable must be initialized if it exists.
5027 // FIXME: We can skip evaluating the body if there's a condition
5028 // variable, as there can't be any case labels within it.
5029 // (The same is true for 'for' statements.)
5030
5031 EvalStmtResult ESR = EvaluateStmt(Result, Info, IS->getThen(), Case);
5032 if (ESR == ESR_Failed)
5033 return ESR;
5034 if (ESR != ESR_CaseNotFound)
5035 return Scope.destroy() ? ESR : ESR_Failed;
5036 if (!IS->getElse())
5037 return ESR_CaseNotFound;
5038
5039 ESR = EvaluateStmt(Result, Info, IS->getElse(), Case);
5040 if (ESR == ESR_Failed)
5041 return ESR;
5042 if (ESR != ESR_CaseNotFound)
5043 return Scope.destroy() ? ESR : ESR_Failed;
5044 return ESR_CaseNotFound;
5045 }
5046
5047 case Stmt::WhileStmtClass: {
5048 EvalStmtResult ESR =
5049 EvaluateLoopBody(Result, Info, cast<WhileStmt>(S)->getBody(), Case);
5050 if (ESR != ESR_Continue)
5051 return ESR;
5052 break;
5053 }
5054
5055 case Stmt::ForStmtClass: {
5056 const ForStmt *FS = cast<ForStmt>(S);
5057 BlockScopeRAII Scope(Info);
5058
5059 // Step into the init statement in case it brings an (uninitialized)
5060 // variable into scope.
5061 if (const Stmt *Init = FS->getInit()) {
5062 EvalStmtResult ESR = EvaluateStmt(Result, Info, Init, Case);
5063 if (ESR != ESR_CaseNotFound) {
5064 assert(ESR != ESR_Succeeded)(static_cast <bool> (ESR != ESR_Succeeded) ? void (0) :
__assert_fail ("ESR != ESR_Succeeded", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5064, __extension__ __PRETTY_FUNCTION__))
;
5065 return ESR;
5066 }
5067 }
5068
5069 EvalStmtResult ESR =
5070 EvaluateLoopBody(Result, Info, FS->getBody(), Case);
5071 if (ESR != ESR_Continue)
5072 return ESR;
5073 if (const auto *Inc = FS->getInc()) {
5074 if (Inc->isValueDependent()) {
5075 if (!EvaluateDependentExpr(Inc, Info))
5076 return ESR_Failed;
5077 } else {
5078 FullExpressionRAII IncScope(Info);
5079 if (!EvaluateIgnoredValue(Info, Inc) || !IncScope.destroy())
5080 return ESR_Failed;
5081 }
5082 }
5083 break;
5084 }
5085
5086 case Stmt::DeclStmtClass: {
5087 // Start the lifetime of any uninitialized variables we encounter. They
5088 // might be used by the selected branch of the switch.
5089 const DeclStmt *DS = cast<DeclStmt>(S);
5090 for (const auto *D : DS->decls()) {
5091 if (const auto *VD = dyn_cast<VarDecl>(D)) {
5092 if (VD->hasLocalStorage() && !VD->getInit())
5093 if (!EvaluateVarDecl(Info, VD))
5094 return ESR_Failed;
5095 // FIXME: If the variable has initialization that can't be jumped
5096 // over, bail out of any immediately-surrounding compound-statement
5097 // too. There can't be any case labels here.
5098 }
5099 }
5100 return ESR_CaseNotFound;
5101 }
5102
5103 default:
5104 return ESR_CaseNotFound;
5105 }
5106 }
5107
5108 switch (S->getStmtClass()) {
5109 default:
5110 if (const Expr *E = dyn_cast<Expr>(S)) {
5111 if (E->isValueDependent()) {
5112 if (!EvaluateDependentExpr(E, Info))
5113 return ESR_Failed;
5114 } else {
5115 // Don't bother evaluating beyond an expression-statement which couldn't
5116 // be evaluated.
5117 // FIXME: Do we need the FullExpressionRAII object here?
5118 // VisitExprWithCleanups should create one when necessary.
5119 FullExpressionRAII Scope(Info);
5120 if (!EvaluateIgnoredValue(Info, E) || !Scope.destroy())
5121 return ESR_Failed;
5122 }
5123 return ESR_Succeeded;
5124 }
5125
5126 Info.FFDiag(S->getBeginLoc());
5127 return ESR_Failed;
5128
5129 case Stmt::NullStmtClass:
5130 return ESR_Succeeded;
5131
5132 case Stmt::DeclStmtClass: {
5133 const DeclStmt *DS = cast<DeclStmt>(S);
5134 for (const auto *D : DS->decls()) {
5135 // Each declaration initialization is its own full-expression.
5136 FullExpressionRAII Scope(Info);
5137 if (!EvaluateDecl(Info, D) && !Info.noteFailure())
5138 return ESR_Failed;
5139 if (!Scope.destroy())
5140 return ESR_Failed;
5141 }
5142 return ESR_Succeeded;
5143 }
5144
5145 case Stmt::ReturnStmtClass: {
5146 const Expr *RetExpr = cast<ReturnStmt>(S)->getRetValue();
5147 FullExpressionRAII Scope(Info);
5148 if (RetExpr && RetExpr->isValueDependent()) {
5149 EvaluateDependentExpr(RetExpr, Info);
5150 // We know we returned, but we don't know what the value is.
5151 return ESR_Failed;
5152 }
5153 if (RetExpr &&
5154 !(Result.Slot
5155 ? EvaluateInPlace(Result.Value, Info, *Result.Slot, RetExpr)
5156 : Evaluate(Result.Value, Info, RetExpr)))
5157 return ESR_Failed;
5158 return Scope.destroy() ? ESR_Returned : ESR_Failed;
5159 }
5160
5161 case Stmt::CompoundStmtClass: {
5162 BlockScopeRAII Scope(Info);
5163
5164 const CompoundStmt *CS = cast<CompoundStmt>(S);
5165 for (const auto *BI : CS->body()) {
5166 EvalStmtResult ESR = EvaluateStmt(Result, Info, BI, Case);
5167 if (ESR == ESR_Succeeded)
5168 Case = nullptr;
5169 else if (ESR != ESR_CaseNotFound) {
5170 if (ESR != ESR_Failed && !Scope.destroy())
5171 return ESR_Failed;
5172 return ESR;
5173 }
5174 }
5175 if (Case)
5176 return ESR_CaseNotFound;
5177 return Scope.destroy() ? ESR_Succeeded : ESR_Failed;
5178 }
5179
5180 case Stmt::IfStmtClass: {
5181 const IfStmt *IS = cast<IfStmt>(S);
5182
5183 // Evaluate the condition, as either a var decl or as an expression.
5184 BlockScopeRAII Scope(Info);
5185 if (const Stmt *Init = IS->getInit()) {
5186 EvalStmtResult ESR = EvaluateStmt(Result, Info, Init);
5187 if (ESR != ESR_Succeeded) {
5188 if (ESR != ESR_Failed && !Scope.destroy())
5189 return ESR_Failed;
5190 return ESR;
5191 }
5192 }
5193 bool Cond;
5194 if (IS->isConsteval())
5195 Cond = IS->isNonNegatedConsteval();
5196 else if (!EvaluateCond(Info, IS->getConditionVariable(), IS->getCond(),
5197 Cond))
5198 return ESR_Failed;
5199
5200 if (const Stmt *SubStmt = Cond ? IS->getThen() : IS->getElse()) {
5201 EvalStmtResult ESR = EvaluateStmt(Result, Info, SubStmt);
5202 if (ESR != ESR_Succeeded) {
5203 if (ESR != ESR_Failed && !Scope.destroy())
5204 return ESR_Failed;
5205 return ESR;
5206 }
5207 }
5208 return Scope.destroy() ? ESR_Succeeded : ESR_Failed;
5209 }
5210
5211 case Stmt::WhileStmtClass: {
5212 const WhileStmt *WS = cast<WhileStmt>(S);
5213 while (true) {
5214 BlockScopeRAII Scope(Info);
5215 bool Continue;
5216 if (!EvaluateCond(Info, WS->getConditionVariable(), WS->getCond(),
5217 Continue))
5218 return ESR_Failed;
5219 if (!Continue)
5220 break;
5221
5222 EvalStmtResult ESR = EvaluateLoopBody(Result, Info, WS->getBody());
5223 if (ESR != ESR_Continue) {
5224 if (ESR != ESR_Failed && !Scope.destroy())
5225 return ESR_Failed;
5226 return ESR;
5227 }
5228 if (!Scope.destroy())
5229 return ESR_Failed;
5230 }
5231 return ESR_Succeeded;
5232 }
5233
5234 case Stmt::DoStmtClass: {
5235 const DoStmt *DS = cast<DoStmt>(S);
5236 bool Continue;
5237 do {
5238 EvalStmtResult ESR = EvaluateLoopBody(Result, Info, DS->getBody(), Case);
5239 if (ESR != ESR_Continue)
5240 return ESR;
5241 Case = nullptr;
5242
5243 if (DS->getCond()->isValueDependent()) {
5244 EvaluateDependentExpr(DS->getCond(), Info);
5245 // Bailout as we don't know whether to keep going or terminate the loop.
5246 return ESR_Failed;
5247 }
5248 FullExpressionRAII CondScope(Info);
5249 if (!EvaluateAsBooleanCondition(DS->getCond(), Continue, Info) ||
5250 !CondScope.destroy())
5251 return ESR_Failed;
5252 } while (Continue);
5253 return ESR_Succeeded;
5254 }
5255
5256 case Stmt::ForStmtClass: {
5257 const ForStmt *FS = cast<ForStmt>(S);
5258 BlockScopeRAII ForScope(Info);
5259 if (FS->getInit()) {
5260 EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getInit());
5261 if (ESR != ESR_Succeeded) {
5262 if (ESR != ESR_Failed && !ForScope.destroy())
5263 return ESR_Failed;
5264 return ESR;
5265 }
5266 }
5267 while (true) {
5268 BlockScopeRAII IterScope(Info);
5269 bool Continue = true;
5270 if (FS->getCond() && !EvaluateCond(Info, FS->getConditionVariable(),
5271 FS->getCond(), Continue))
5272 return ESR_Failed;
5273 if (!Continue)
5274 break;
5275
5276 EvalStmtResult ESR = EvaluateLoopBody(Result, Info, FS->getBody());
5277 if (ESR != ESR_Continue) {
5278 if (ESR != ESR_Failed && (!IterScope.destroy() || !ForScope.destroy()))
5279 return ESR_Failed;
5280 return ESR;
5281 }
5282
5283 if (const auto *Inc = FS->getInc()) {
5284 if (Inc->isValueDependent()) {
5285 if (!EvaluateDependentExpr(Inc, Info))
5286 return ESR_Failed;
5287 } else {
5288 FullExpressionRAII IncScope(Info);
5289 if (!EvaluateIgnoredValue(Info, Inc) || !IncScope.destroy())
5290 return ESR_Failed;
5291 }
5292 }
5293
5294 if (!IterScope.destroy())
5295 return ESR_Failed;
5296 }
5297 return ForScope.destroy() ? ESR_Succeeded : ESR_Failed;
5298 }
5299
5300 case Stmt::CXXForRangeStmtClass: {
5301 const CXXForRangeStmt *FS = cast<CXXForRangeStmt>(S);
5302 BlockScopeRAII Scope(Info);
5303
5304 // Evaluate the init-statement if present.
5305 if (FS->getInit()) {
5306 EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getInit());
5307 if (ESR != ESR_Succeeded) {
5308 if (ESR != ESR_Failed && !Scope.destroy())
5309 return ESR_Failed;
5310 return ESR;
5311 }
5312 }
5313
5314 // Initialize the __range variable.
5315 EvalStmtResult ESR = EvaluateStmt(Result, Info, FS->getRangeStmt());
5316 if (ESR != ESR_Succeeded) {
5317 if (ESR != ESR_Failed && !Scope.destroy())
5318 return ESR_Failed;
5319 return ESR;
5320 }
5321
5322 // In error-recovery cases it's possible to get here even if we failed to
5323 // synthesize the __begin and __end variables.
5324 if (!FS->getBeginStmt() || !FS->getEndStmt() || !FS->getCond())
5325 return ESR_Failed;
5326
5327 // Create the __begin and __end iterators.
5328 ESR = EvaluateStmt(Result, Info, FS->getBeginStmt());
5329 if (ESR != ESR_Succeeded) {
5330 if (ESR != ESR_Failed && !Scope.destroy())
5331 return ESR_Failed;
5332 return ESR;
5333 }
5334 ESR = EvaluateStmt(Result, Info, FS->getEndStmt());
5335 if (ESR != ESR_Succeeded) {
5336 if (ESR != ESR_Failed && !Scope.destroy())
5337 return ESR_Failed;
5338 return ESR;
5339 }
5340
5341 while (true) {
5342 // Condition: __begin != __end.
5343 {
5344 if (FS->getCond()->isValueDependent()) {
5345 EvaluateDependentExpr(FS->getCond(), Info);
5346 // We don't know whether to keep going or terminate the loop.
5347 return ESR_Failed;
5348 }
5349 bool Continue = true;
5350 FullExpressionRAII CondExpr(Info);
5351 if (!EvaluateAsBooleanCondition(FS->getCond(), Continue, Info))
5352 return ESR_Failed;
5353 if (!Continue)
5354 break;
5355 }
5356
5357 // User's variable declaration, initialized by *__begin.
5358 BlockScopeRAII InnerScope(Info);
5359 ESR = EvaluateStmt(Result, Info, FS->getLoopVarStmt());
5360 if (ESR != ESR_Succeeded) {
5361 if (ESR != ESR_Failed && (!InnerScope.destroy() || !Scope.destroy()))
5362 return ESR_Failed;
5363 return ESR;
5364 }
5365
5366 // Loop body.
5367 ESR = EvaluateLoopBody(Result, Info, FS->getBody());
5368 if (ESR != ESR_Continue) {
5369 if (ESR != ESR_Failed && (!InnerScope.destroy() || !Scope.destroy()))
5370 return ESR_Failed;
5371 return ESR;
5372 }
5373 if (FS->getInc()->isValueDependent()) {
5374 if (!EvaluateDependentExpr(FS->getInc(), Info))
5375 return ESR_Failed;
5376 } else {
5377 // Increment: ++__begin
5378 if (!EvaluateIgnoredValue(Info, FS->getInc()))
5379 return ESR_Failed;
5380 }
5381
5382 if (!InnerScope.destroy())
5383 return ESR_Failed;
5384 }
5385
5386 return Scope.destroy() ? ESR_Succeeded : ESR_Failed;
5387 }
5388
5389 case Stmt::SwitchStmtClass:
5390 return EvaluateSwitch(Result, Info, cast<SwitchStmt>(S));
5391
5392 case Stmt::ContinueStmtClass:
5393 return ESR_Continue;
5394
5395 case Stmt::BreakStmtClass:
5396 return ESR_Break;
5397
5398 case Stmt::LabelStmtClass:
5399 return EvaluateStmt(Result, Info, cast<LabelStmt>(S)->getSubStmt(), Case);
5400
5401 case Stmt::AttributedStmtClass:
5402 // As a general principle, C++11 attributes can be ignored without
5403 // any semantic impact.
5404 return EvaluateStmt(Result, Info, cast<AttributedStmt>(S)->getSubStmt(),
5405 Case);
5406
5407 case Stmt::CaseStmtClass:
5408 case Stmt::DefaultStmtClass:
5409 return EvaluateStmt(Result, Info, cast<SwitchCase>(S)->getSubStmt(), Case);
5410 case Stmt::CXXTryStmtClass:
5411 // Evaluate try blocks by evaluating all sub statements.
5412 return EvaluateStmt(Result, Info, cast<CXXTryStmt>(S)->getTryBlock(), Case);
5413 }
5414}
5415
5416/// CheckTrivialDefaultConstructor - Check whether a constructor is a trivial
5417/// default constructor. If so, we'll fold it whether or not it's marked as
5418/// constexpr. If it is marked as constexpr, we will never implicitly define it,
5419/// so we need special handling.
5420static bool CheckTrivialDefaultConstructor(EvalInfo &Info, SourceLocation Loc,
5421 const CXXConstructorDecl *CD,
5422 bool IsValueInitialization) {
5423 if (!CD->isTrivial() || !CD->isDefaultConstructor())
5424 return false;
5425
5426 // Value-initialization does not call a trivial default constructor, so such a
5427 // call is a core constant expression whether or not the constructor is
5428 // constexpr.
5429 if (!CD->isConstexpr() && !IsValueInitialization) {
5430 if (Info.getLangOpts().CPlusPlus11) {
5431 // FIXME: If DiagDecl is an implicitly-declared special member function,
5432 // we should be much more explicit about why it's not constexpr.
5433 Info.CCEDiag(Loc, diag::note_constexpr_invalid_function, 1)
5434 << /*IsConstexpr*/0 << /*IsConstructor*/1 << CD;
5435 Info.Note(CD->getLocation(), diag::note_declared_at);
5436 } else {
5437 Info.CCEDiag(Loc, diag::note_invalid_subexpr_in_const_expr);
5438 }
5439 }
5440 return true;
5441}
5442
5443/// CheckConstexprFunction - Check that a function can be called in a constant
5444/// expression.
5445static bool CheckConstexprFunction(EvalInfo &Info, SourceLocation CallLoc,
5446 const FunctionDecl *Declaration,
5447 const FunctionDecl *Definition,
5448 const Stmt *Body) {
5449 // Potential constant expressions can contain calls to declared, but not yet
5450 // defined, constexpr functions.
5451 if (Info.checkingPotentialConstantExpression() && !Definition &&
5452 Declaration->isConstexpr())
5453 return false;
5454
5455 // Bail out if the function declaration itself is invalid. We will
5456 // have produced a relevant diagnostic while parsing it, so just
5457 // note the problematic sub-expression.
5458 if (Declaration->isInvalidDecl()) {
5459 Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr);
5460 return false;
5461 }
5462
5463 // DR1872: An instantiated virtual constexpr function can't be called in a
5464 // constant expression (prior to C++20). We can still constant-fold such a
5465 // call.
5466 if (!Info.Ctx.getLangOpts().CPlusPlus20 && isa<CXXMethodDecl>(Declaration) &&
5467 cast<CXXMethodDecl>(Declaration)->isVirtual())
5468 Info.CCEDiag(CallLoc, diag::note_constexpr_virtual_call);
5469
5470 if (Definition && Definition->isInvalidDecl()) {
5471 Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr);
5472 return false;
5473 }
5474
5475 // Can we evaluate this function call?
5476 if (Definition && Definition->isConstexpr() && Body)
5477 return true;
5478
5479 if (Info.getLangOpts().CPlusPlus11) {
5480 const FunctionDecl *DiagDecl = Definition ? Definition : Declaration;
5481
5482 // If this function is not constexpr because it is an inherited
5483 // non-constexpr constructor, diagnose that directly.
5484 auto *CD = dyn_cast<CXXConstructorDecl>(DiagDecl);
5485 if (CD && CD->isInheritingConstructor()) {
5486 auto *Inherited = CD->getInheritedConstructor().getConstructor();
5487 if (!Inherited->isConstexpr())
5488 DiagDecl = CD = Inherited;
5489 }
5490
5491 // FIXME: If DiagDecl is an implicitly-declared special member function
5492 // or an inheriting constructor, we should be much more explicit about why
5493 // it's not constexpr.
5494 if (CD && CD->isInheritingConstructor())
5495 Info.FFDiag(CallLoc, diag::note_constexpr_invalid_inhctor, 1)
5496 << CD->getInheritedConstructor().getConstructor()->getParent();
5497 else
5498 Info.FFDiag(CallLoc, diag::note_constexpr_invalid_function, 1)
5499 << DiagDecl->isConstexpr() << (bool)CD << DiagDecl;
5500 Info.Note(DiagDecl->getLocation(), diag::note_declared_at);
5501 } else {
5502 Info.FFDiag(CallLoc, diag::note_invalid_subexpr_in_const_expr);
5503 }
5504 return false;
5505}
5506
5507namespace {
5508struct CheckDynamicTypeHandler {
5509 AccessKinds AccessKind;
5510 typedef bool result_type;
5511 bool failed() { return false; }
5512 bool found(APValue &Subobj, QualType SubobjType) { return true; }
5513 bool found(APSInt &Value, QualType SubobjType) { return true; }
5514 bool found(APFloat &Value, QualType SubobjType) { return true; }
5515};
5516} // end anonymous namespace
5517
5518/// Check that we can access the notional vptr of an object / determine its
5519/// dynamic type.
5520static bool checkDynamicType(EvalInfo &Info, const Expr *E, const LValue &This,
5521 AccessKinds AK, bool Polymorphic) {
5522 if (This.Designator.Invalid)
5523 return false;
5524
5525 CompleteObject Obj = findCompleteObject(Info, E, AK, This, QualType());
5526
5527 if (!Obj)
5528 return false;
5529
5530 if (!Obj.Value) {
5531 // The object is not usable in constant expressions, so we can't inspect
5532 // its value to see if it's in-lifetime or what the active union members
5533 // are. We can still check for a one-past-the-end lvalue.
5534 if (This.Designator.isOnePastTheEnd() ||
5535 This.Designator.isMostDerivedAnUnsizedArray()) {
5536 Info.FFDiag(E, This.Designator.isOnePastTheEnd()
5537 ? diag::note_constexpr_access_past_end
5538 : diag::note_constexpr_access_unsized_array)
5539 << AK;
5540 return false;
5541 } else if (Polymorphic) {
5542 // Conservatively refuse to perform a polymorphic operation if we would
5543 // not be able to read a notional 'vptr' value.
5544 APValue Val;
5545 This.moveInto(Val);
5546 QualType StarThisType =
5547 Info.Ctx.getLValueReferenceType(This.Designator.getType(Info.Ctx));
5548 Info.FFDiag(E, diag::note_constexpr_polymorphic_unknown_dynamic_type)
5549 << AK << Val.getAsString(Info.Ctx, StarThisType);
5550 return false;
5551 }
5552 return true;
5553 }
5554
5555 CheckDynamicTypeHandler Handler{AK};
5556 return Obj && findSubobject(Info, E, Obj, This.Designator, Handler);
5557}
5558
5559/// Check that the pointee of the 'this' pointer in a member function call is
5560/// either within its lifetime or in its period of construction or destruction.
5561static bool
5562checkNonVirtualMemberCallThisPointer(EvalInfo &Info, const Expr *E,
5563 const LValue &This,
5564 const CXXMethodDecl *NamedMember) {
5565 return checkDynamicType(
5566 Info, E, This,
5567 isa<CXXDestructorDecl>(NamedMember) ? AK_Destroy : AK_MemberCall, false);
5568}
5569
5570struct DynamicType {
5571 /// The dynamic class type of the object.
5572 const CXXRecordDecl *Type;
5573 /// The corresponding path length in the lvalue.
5574 unsigned PathLength;
5575};
5576
5577static const CXXRecordDecl *getBaseClassType(SubobjectDesignator &Designator,
5578 unsigned PathLength) {
5579 assert(PathLength >= Designator.MostDerivedPathLength && PathLength <=(static_cast <bool> (PathLength >= Designator.MostDerivedPathLength
&& PathLength <= Designator.Entries.size() &&
"invalid path length") ? void (0) : __assert_fail ("PathLength >= Designator.MostDerivedPathLength && PathLength <= Designator.Entries.size() && \"invalid path length\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5580, __extension__ __PRETTY_FUNCTION__))
5580 Designator.Entries.size() && "invalid path length")(static_cast <bool> (PathLength >= Designator.MostDerivedPathLength
&& PathLength <= Designator.Entries.size() &&
"invalid path length") ? void (0) : __assert_fail ("PathLength >= Designator.MostDerivedPathLength && PathLength <= Designator.Entries.size() && \"invalid path length\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5580, __extension__ __PRETTY_FUNCTION__))
;
5581 return (PathLength == Designator.MostDerivedPathLength)
5582 ? Designator.MostDerivedType->getAsCXXRecordDecl()
5583 : getAsBaseClass(Designator.Entries[PathLength - 1]);
5584}
5585
5586/// Determine the dynamic type of an object.
5587static Optional<DynamicType> ComputeDynamicType(EvalInfo &Info, const Expr *E,
5588 LValue &This, AccessKinds AK) {
5589 // If we don't have an lvalue denoting an object of class type, there is no
5590 // meaningful dynamic type. (We consider objects of non-class type to have no
5591 // dynamic type.)
5592 if (!checkDynamicType(Info, E, This, AK, true))
5593 return None;
5594
5595 // Refuse to compute a dynamic type in the presence of virtual bases. This
5596 // shouldn't happen other than in constant-folding situations, since literal
5597 // types can't have virtual bases.
5598 //
5599 // Note that consumers of DynamicType assume that the type has no virtual
5600 // bases, and will need modifications if this restriction is relaxed.
5601 const CXXRecordDecl *Class =
5602 This.Designator.MostDerivedType->getAsCXXRecordDecl();
5603 if (!Class || Class->getNumVBases()) {
5604 Info.FFDiag(E);
5605 return None;
5606 }
5607
5608 // FIXME: For very deep class hierarchies, it might be beneficial to use a
5609 // binary search here instead. But the overwhelmingly common case is that
5610 // we're not in the middle of a constructor, so it probably doesn't matter
5611 // in practice.
5612 ArrayRef<APValue::LValuePathEntry> Path = This.Designator.Entries;
5613 for (unsigned PathLength = This.Designator.MostDerivedPathLength;
5614 PathLength <= Path.size(); ++PathLength) {
5615 switch (Info.isEvaluatingCtorDtor(This.getLValueBase(),
5616 Path.slice(0, PathLength))) {
5617 case ConstructionPhase::Bases:
5618 case ConstructionPhase::DestroyingBases:
5619 // We're constructing or destroying a base class. This is not the dynamic
5620 // type.
5621 break;
5622
5623 case ConstructionPhase::None:
5624 case ConstructionPhase::AfterBases:
5625 case ConstructionPhase::AfterFields:
5626 case ConstructionPhase::Destroying:
5627 // We've finished constructing the base classes and not yet started
5628 // destroying them again, so this is the dynamic type.
5629 return DynamicType{getBaseClassType(This.Designator, PathLength),
5630 PathLength};
5631 }
5632 }
5633
5634 // CWG issue 1517: we're constructing a base class of the object described by
5635 // 'This', so that object has not yet begun its period of construction and
5636 // any polymorphic operation on it results in undefined behavior.
5637 Info.FFDiag(E);
5638 return None;
5639}
5640
5641/// Perform virtual dispatch.
5642static const CXXMethodDecl *HandleVirtualDispatch(
5643 EvalInfo &Info, const Expr *E, LValue &This, const CXXMethodDecl *Found,
5644 llvm::SmallVectorImpl<QualType> &CovariantAdjustmentPath) {
5645 Optional<DynamicType> DynType = ComputeDynamicType(
5646 Info, E, This,
5647 isa<CXXDestructorDecl>(Found) ? AK_Destroy : AK_MemberCall);
5648 if (!DynType)
5649 return nullptr;
5650
5651 // Find the final overrider. It must be declared in one of the classes on the
5652 // path from the dynamic type to the static type.
5653 // FIXME: If we ever allow literal types to have virtual base classes, that
5654 // won't be true.
5655 const CXXMethodDecl *Callee = Found;
5656 unsigned PathLength = DynType->PathLength;
5657 for (/**/; PathLength <= This.Designator.Entries.size(); ++PathLength) {
5658 const CXXRecordDecl *Class = getBaseClassType(This.Designator, PathLength);
5659 const CXXMethodDecl *Overrider =
5660 Found->getCorrespondingMethodDeclaredInClass(Class, false);
5661 if (Overrider) {
5662 Callee = Overrider;
5663 break;
5664 }
5665 }
5666
5667 // C++2a [class.abstract]p6:
5668 // the effect of making a virtual call to a pure virtual function [...] is
5669 // undefined
5670 if (Callee->isPure()) {
5671 Info.FFDiag(E, diag::note_constexpr_pure_virtual_call, 1) << Callee;
5672 Info.Note(Callee->getLocation(), diag::note_declared_at);
5673 return nullptr;
5674 }
5675
5676 // If necessary, walk the rest of the path to determine the sequence of
5677 // covariant adjustment steps to apply.
5678 if (!Info.Ctx.hasSameUnqualifiedType(Callee->getReturnType(),
5679 Found->getReturnType())) {
5680 CovariantAdjustmentPath.push_back(Callee->getReturnType());
5681 for (unsigned CovariantPathLength = PathLength + 1;
5682 CovariantPathLength != This.Designator.Entries.size();
5683 ++CovariantPathLength) {
5684 const CXXRecordDecl *NextClass =
5685 getBaseClassType(This.Designator, CovariantPathLength);
5686 const CXXMethodDecl *Next =
5687 Found->getCorrespondingMethodDeclaredInClass(NextClass, false);
5688 if (Next && !Info.Ctx.hasSameUnqualifiedType(
5689 Next->getReturnType(), CovariantAdjustmentPath.back()))
5690 CovariantAdjustmentPath.push_back(Next->getReturnType());
5691 }
5692 if (!Info.Ctx.hasSameUnqualifiedType(Found->getReturnType(),
5693 CovariantAdjustmentPath.back()))
5694 CovariantAdjustmentPath.push_back(Found->getReturnType());
5695 }
5696
5697 // Perform 'this' adjustment.
5698 if (!CastToDerivedClass(Info, E, This, Callee->getParent(), PathLength))
5699 return nullptr;
5700
5701 return Callee;
5702}
5703
5704/// Perform the adjustment from a value returned by a virtual function to
5705/// a value of the statically expected type, which may be a pointer or
5706/// reference to a base class of the returned type.
5707static bool HandleCovariantReturnAdjustment(EvalInfo &Info, const Expr *E,
5708 APValue &Result,
5709 ArrayRef<QualType> Path) {
5710 assert(Result.isLValue() &&(static_cast <bool> (Result.isLValue() && "unexpected kind of APValue for covariant return"
) ? void (0) : __assert_fail ("Result.isLValue() && \"unexpected kind of APValue for covariant return\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5711, __extension__ __PRETTY_FUNCTION__))
5711 "unexpected kind of APValue for covariant return")(static_cast <bool> (Result.isLValue() && "unexpected kind of APValue for covariant return"
) ? void (0) : __assert_fail ("Result.isLValue() && \"unexpected kind of APValue for covariant return\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5711, __extension__ __PRETTY_FUNCTION__))
;
5712 if (Result.isNullPointer())
5713 return true;
5714
5715 LValue LVal;
5716 LVal.setFrom(Info.Ctx, Result);
5717
5718 const CXXRecordDecl *OldClass = Path[0]->getPointeeCXXRecordDecl();
5719 for (unsigned I = 1; I != Path.size(); ++I) {
5720 const CXXRecordDecl *NewClass = Path[I]->getPointeeCXXRecordDecl();
5721 assert(OldClass && NewClass && "unexpected kind of covariant return")(static_cast <bool> (OldClass && NewClass &&
"unexpected kind of covariant return") ? void (0) : __assert_fail
("OldClass && NewClass && \"unexpected kind of covariant return\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5721, __extension__ __PRETTY_FUNCTION__))
;
5722 if (OldClass != NewClass &&
5723 !CastToBaseClass(Info, E, LVal, OldClass, NewClass))
5724 return false;
5725 OldClass = NewClass;
5726 }
5727
5728 LVal.moveInto(Result);
5729 return true;
5730}
5731
5732/// Determine whether \p Base, which is known to be a direct base class of
5733/// \p Derived, is a public base class.
5734static bool isBaseClassPublic(const CXXRecordDecl *Derived,
5735 const CXXRecordDecl *Base) {
5736 for (const CXXBaseSpecifier &BaseSpec : Derived->bases()) {
5737 auto *BaseClass = BaseSpec.getType()->getAsCXXRecordDecl();
5738 if (BaseClass && declaresSameEntity(BaseClass, Base))
5739 return BaseSpec.getAccessSpecifier() == AS_public;
5740 }
5741 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-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5741)
;
5742}
5743
5744/// Apply the given dynamic cast operation on the provided lvalue.
5745///
5746/// This implements the hard case of dynamic_cast, requiring a "runtime check"
5747/// to find a suitable target subobject.
5748static bool HandleDynamicCast(EvalInfo &Info, const ExplicitCastExpr *E,
5749 LValue &Ptr) {
5750 // We can't do anything with a non-symbolic pointer value.
5751 SubobjectDesignator &D = Ptr.Designator;
5752 if (D.Invalid)
5753 return false;
5754
5755 // C++ [expr.dynamic.cast]p6:
5756 // If v is a null pointer value, the result is a null pointer value.
5757 if (Ptr.isNullPointer() && !E->isGLValue())
5758 return true;
5759
5760 // For all the other cases, we need the pointer to point to an object within
5761 // its lifetime / period of construction / destruction, and we need to know
5762 // its dynamic type.
5763 Optional<DynamicType> DynType =
5764 ComputeDynamicType(Info, E, Ptr, AK_DynamicCast);
5765 if (!DynType)
5766 return false;
5767
5768 // C++ [expr.dynamic.cast]p7:
5769 // If T is "pointer to cv void", then the result is a pointer to the most
5770 // derived object
5771 if (E->getType()->isVoidPointerType())
5772 return CastToDerivedClass(Info, E, Ptr, DynType->Type, DynType->PathLength);
5773
5774 const CXXRecordDecl *C = E->getTypeAsWritten()->getPointeeCXXRecordDecl();
5775 assert(C && "dynamic_cast target is not void pointer nor class")(static_cast <bool> (C && "dynamic_cast target is not void pointer nor class"
) ? void (0) : __assert_fail ("C && \"dynamic_cast target is not void pointer nor class\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5775, __extension__ __PRETTY_FUNCTION__))
;
5776 CanQualType CQT = Info.Ctx.getCanonicalType(Info.Ctx.getRecordType(C));
5777
5778 auto RuntimeCheckFailed = [&] (CXXBasePaths *Paths) {
5779 // C++ [expr.dynamic.cast]p9:
5780 if (!E->isGLValue()) {
5781 // The value of a failed cast to pointer type is the null pointer value
5782 // of the required result type.
5783 Ptr.setNull(Info.Ctx, E->getType());
5784 return true;
5785 }
5786
5787 // A failed cast to reference type throws [...] std::bad_cast.
5788 unsigned DiagKind;
5789 if (!Paths && (declaresSameEntity(DynType->Type, C) ||
5790 DynType->Type->isDerivedFrom(C)))
5791 DiagKind = 0;
5792 else if (!Paths || Paths->begin() == Paths->end())
5793 DiagKind = 1;
5794 else if (Paths->isAmbiguous(CQT))
5795 DiagKind = 2;
5796 else {
5797 assert(Paths->front().Access != AS_public && "why did the cast fail?")(static_cast <bool> (Paths->front().Access != AS_public
&& "why did the cast fail?") ? void (0) : __assert_fail
("Paths->front().Access != AS_public && \"why did the cast fail?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5797, __extension__ __PRETTY_FUNCTION__))
;
5798 DiagKind = 3;
5799 }
5800 Info.FFDiag(E, diag::note_constexpr_dynamic_cast_to_reference_failed)
5801 << DiagKind << Ptr.Designator.getType(Info.Ctx)
5802 << Info.Ctx.getRecordType(DynType->Type)
5803 << E->getType().getUnqualifiedType();
5804 return false;
5805 };
5806
5807 // Runtime check, phase 1:
5808 // Walk from the base subobject towards the derived object looking for the
5809 // target type.
5810 for (int PathLength = Ptr.Designator.Entries.size();
5811 PathLength >= (int)DynType->PathLength; --PathLength) {
5812 const CXXRecordDecl *Class = getBaseClassType(Ptr.Designator, PathLength);
5813 if (declaresSameEntity(Class, C))
5814 return CastToDerivedClass(Info, E, Ptr, Class, PathLength);
5815 // We can only walk across public inheritance edges.
5816 if (PathLength > (int)DynType->PathLength &&
5817 !isBaseClassPublic(getBaseClassType(Ptr.Designator, PathLength - 1),
5818 Class))
5819 return RuntimeCheckFailed(nullptr);
5820 }
5821
5822 // Runtime check, phase 2:
5823 // Search the dynamic type for an unambiguous public base of type C.
5824 CXXBasePaths Paths(/*FindAmbiguities=*/true,
5825 /*RecordPaths=*/true, /*DetectVirtual=*/false);
5826 if (DynType->Type->isDerivedFrom(C, Paths) && !Paths.isAmbiguous(CQT) &&
5827 Paths.front().Access == AS_public) {
5828 // Downcast to the dynamic type...
5829 if (!CastToDerivedClass(Info, E, Ptr, DynType->Type, DynType->PathLength))
5830 return false;
5831 // ... then upcast to the chosen base class subobject.
5832 for (CXXBasePathElement &Elem : Paths.front())
5833 if (!HandleLValueBase(Info, E, Ptr, Elem.Class, Elem.Base))
5834 return false;
5835 return true;
5836 }
5837
5838 // Otherwise, the runtime check fails.
5839 return RuntimeCheckFailed(&Paths);
5840}
5841
5842namespace {
5843struct StartLifetimeOfUnionMemberHandler {
5844 EvalInfo &Info;
5845 const Expr *LHSExpr;
5846 const FieldDecl *Field;
5847 bool DuringInit;
5848 bool Failed = false;
5849 static const AccessKinds AccessKind = AK_Assign;
5850
5851 typedef bool result_type;
5852 bool failed() { return Failed; }
5853 bool found(APValue &Subobj, QualType SubobjType) {
5854 // We are supposed to perform no initialization but begin the lifetime of
5855 // the object. We interpret that as meaning to do what default
5856 // initialization of the object would do if all constructors involved were
5857 // trivial:
5858 // * All base, non-variant member, and array element subobjects' lifetimes
5859 // begin
5860 // * No variant members' lifetimes begin
5861 // * All scalar subobjects whose lifetimes begin have indeterminate values
5862 assert(SubobjType->isUnionType())(static_cast <bool> (SubobjType->isUnionType()) ? void
(0) : __assert_fail ("SubobjType->isUnionType()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5862, __extension__ __PRETTY_FUNCTION__))
;
5863 if (declaresSameEntity(Subobj.getUnionField(), Field)) {
5864 // This union member is already active. If it's also in-lifetime, there's
5865 // nothing to do.
5866 if (Subobj.getUnionValue().hasValue())
5867 return true;
5868 } else if (DuringInit) {
5869 // We're currently in the process of initializing a different union
5870 // member. If we carried on, that initialization would attempt to
5871 // store to an inactive union member, resulting in undefined behavior.
5872 Info.FFDiag(LHSExpr,
5873 diag::note_constexpr_union_member_change_during_init);
5874 return false;
5875 }
5876 APValue Result;
5877 Failed = !getDefaultInitValue(Field->getType(), Result);
5878 Subobj.setUnion(Field, Result);
5879 return true;
5880 }
5881 bool found(APSInt &Value, QualType SubobjType) {
5882 llvm_unreachable("wrong value kind for union object")::llvm::llvm_unreachable_internal("wrong value kind for union object"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5882)
;
5883 }
5884 bool found(APFloat &Value, QualType SubobjType) {
5885 llvm_unreachable("wrong value kind for union object")::llvm::llvm_unreachable_internal("wrong value kind for union object"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5885)
;
5886 }
5887};
5888} // end anonymous namespace
5889
5890const AccessKinds StartLifetimeOfUnionMemberHandler::AccessKind;
5891
5892/// Handle a builtin simple-assignment or a call to a trivial assignment
5893/// operator whose left-hand side might involve a union member access. If it
5894/// does, implicitly start the lifetime of any accessed union elements per
5895/// C++20 [class.union]5.
5896static bool HandleUnionActiveMemberChange(EvalInfo &Info, const Expr *LHSExpr,
5897 const LValue &LHS) {
5898 if (LHS.InvalidBase || LHS.Designator.Invalid)
5899 return false;
5900
5901 llvm::SmallVector<std::pair<unsigned, const FieldDecl*>, 4> UnionPathLengths;
5902 // C++ [class.union]p5:
5903 // define the set S(E) of subexpressions of E as follows:
5904 unsigned PathLength = LHS.Designator.Entries.size();
5905 for (const Expr *E = LHSExpr; E != nullptr;) {
5906 // -- If E is of the form A.B, S(E) contains the elements of S(A)...
5907 if (auto *ME = dyn_cast<MemberExpr>(E)) {
5908 auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
5909 // Note that we can't implicitly start the lifetime of a reference,
5910 // so we don't need to proceed any further if we reach one.
5911 if (!FD || FD->getType()->isReferenceType())
5912 break;
5913
5914 // ... and also contains A.B if B names a union member ...
5915 if (FD->getParent()->isUnion()) {
5916 // ... of a non-class, non-array type, or of a class type with a
5917 // trivial default constructor that is not deleted, or an array of
5918 // such types.
5919 auto *RD =
5920 FD->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
5921 if (!RD || RD->hasTrivialDefaultConstructor())
5922 UnionPathLengths.push_back({PathLength - 1, FD});
5923 }
5924
5925 E = ME->getBase();
5926 --PathLength;
5927 assert(declaresSameEntity(FD,(static_cast <bool> (declaresSameEntity(FD, LHS.Designator
.Entries[PathLength] .getAsBaseOrMember().getPointer())) ? void
(0) : __assert_fail ("declaresSameEntity(FD, LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5929, __extension__ __PRETTY_FUNCTION__))
5928 LHS.Designator.Entries[PathLength](static_cast <bool> (declaresSameEntity(FD, LHS.Designator
.Entries[PathLength] .getAsBaseOrMember().getPointer())) ? void
(0) : __assert_fail ("declaresSameEntity(FD, LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5929, __extension__ __PRETTY_FUNCTION__))
5929 .getAsBaseOrMember().getPointer()))(static_cast <bool> (declaresSameEntity(FD, LHS.Designator
.Entries[PathLength] .getAsBaseOrMember().getPointer())) ? void
(0) : __assert_fail ("declaresSameEntity(FD, LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5929, __extension__ __PRETTY_FUNCTION__))
;
5930
5931 // -- If E is of the form A[B] and is interpreted as a built-in array
5932 // subscripting operator, S(E) is [S(the array operand, if any)].
5933 } else if (auto *ASE = dyn_cast<ArraySubscriptExpr>(E)) {
5934 // Step over an ArrayToPointerDecay implicit cast.
5935 auto *Base = ASE->getBase()->IgnoreImplicit();
5936 if (!Base->getType()->isArrayType())
5937 break;
5938
5939 E = Base;
5940 --PathLength;
5941
5942 } else if (auto *ICE = dyn_cast<ImplicitCastExpr>(E)) {
5943 // Step over a derived-to-base conversion.
5944 E = ICE->getSubExpr();
5945 if (ICE->getCastKind() == CK_NoOp)
5946 continue;
5947 if (ICE->getCastKind() != CK_DerivedToBase &&
5948 ICE->getCastKind() != CK_UncheckedDerivedToBase)
5949 break;
5950 // Walk path backwards as we walk up from the base to the derived class.
5951 for (const CXXBaseSpecifier *Elt : llvm::reverse(ICE->path())) {
5952 --PathLength;
5953 (void)Elt;
5954 assert(declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(),(static_cast <bool> (declaresSameEntity(Elt->getType
()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength
] .getAsBaseOrMember().getPointer())) ? void (0) : __assert_fail
("declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5956, __extension__ __PRETTY_FUNCTION__))
5955 LHS.Designator.Entries[PathLength](static_cast <bool> (declaresSameEntity(Elt->getType
()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength
] .getAsBaseOrMember().getPointer())) ? void (0) : __assert_fail
("declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5956, __extension__ __PRETTY_FUNCTION__))
5956 .getAsBaseOrMember().getPointer()))(static_cast <bool> (declaresSameEntity(Elt->getType
()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength
] .getAsBaseOrMember().getPointer())) ? void (0) : __assert_fail
("declaresSameEntity(Elt->getType()->getAsCXXRecordDecl(), LHS.Designator.Entries[PathLength] .getAsBaseOrMember().getPointer())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 5956, __extension__ __PRETTY_FUNCTION__))
;
5957 }
5958
5959 // -- Otherwise, S(E) is empty.
5960 } else {
5961 break;
5962 }
5963 }
5964
5965 // Common case: no unions' lifetimes are started.
5966 if (UnionPathLengths.empty())
5967 return true;
5968
5969 // if modification of X [would access an inactive union member], an object
5970 // of the type of X is implicitly created
5971 CompleteObject Obj =
5972 findCompleteObject(Info, LHSExpr, AK_Assign, LHS, LHSExpr->getType());
5973 if (!Obj)
5974 return false;
5975 for (std::pair<unsigned, const FieldDecl *> LengthAndField :
5976 llvm::reverse(UnionPathLengths)) {
5977 // Form a designator for the union object.
5978 SubobjectDesignator D = LHS.Designator;
5979 D.truncate(Info.Ctx, LHS.Base, LengthAndField.first);
5980
5981 bool DuringInit = Info.isEvaluatingCtorDtor(LHS.Base, D.Entries) ==
5982 ConstructionPhase::AfterBases;
5983 StartLifetimeOfUnionMemberHandler StartLifetime{
5984 Info, LHSExpr, LengthAndField.second, DuringInit};
5985 if (!findSubobject(Info, LHSExpr, Obj, D, StartLifetime))
5986 return false;
5987 }
5988
5989 return true;
5990}
5991
5992static bool EvaluateCallArg(const ParmVarDecl *PVD, const Expr *Arg,
5993 CallRef Call, EvalInfo &Info,
5994 bool NonNull = false) {
5995 LValue LV;
5996 // Create the parameter slot and register its destruction. For a vararg
5997 // argument, create a temporary.
5998 // FIXME: For calling conventions that destroy parameters in the callee,
5999 // should we consider performing destruction when the function returns
6000 // instead?
6001 APValue &V = PVD ? Info.CurrentCall->createParam(Call, PVD, LV)
6002 : Info.CurrentCall->createTemporary(Arg, Arg->getType(),
6003 ScopeKind::Call, LV);
6004 if (!EvaluateInPlace(V, Info, LV, Arg))
6005 return false;
6006
6007 // Passing a null pointer to an __attribute__((nonnull)) parameter results in
6008 // undefined behavior, so is non-constant.
6009 if (NonNull && V.isLValue() && V.isNullPointer()) {
6010 Info.CCEDiag(Arg, diag::note_non_null_attribute_failed);
6011 return false;
6012 }
6013
6014 return true;
6015}
6016
6017/// Evaluate the arguments to a function call.
6018static bool EvaluateArgs(ArrayRef<const Expr *> Args, CallRef Call,
6019 EvalInfo &Info, const FunctionDecl *Callee,
6020 bool RightToLeft = false) {
6021 bool Success = true;
6022 llvm::SmallBitVector ForbiddenNullArgs;
6023 if (Callee->hasAttr<NonNullAttr>()) {
6024 ForbiddenNullArgs.resize(Args.size());
6025 for (const auto *Attr : Callee->specific_attrs<NonNullAttr>()) {
6026 if (!Attr->args_size()) {
6027 ForbiddenNullArgs.set();
6028 break;
6029 } else
6030 for (auto Idx : Attr->args()) {
6031 unsigned ASTIdx = Idx.getASTIndex();
6032 if (ASTIdx >= Args.size())
6033 continue;
6034 ForbiddenNullArgs[ASTIdx] = 1;
6035 }
6036 }
6037 }
6038 for (unsigned I = 0; I < Args.size(); I++) {
6039 unsigned Idx = RightToLeft ? Args.size() - I - 1 : I;
6040 const ParmVarDecl *PVD =
6041 Idx < Callee->getNumParams() ? Callee->getParamDecl(Idx) : nullptr;
6042 bool NonNull = !ForbiddenNullArgs.empty() && ForbiddenNullArgs[Idx];
6043 if (!EvaluateCallArg(PVD, Args[Idx], Call, Info, NonNull)) {
6044 // If we're checking for a potential constant expression, evaluate all
6045 // initializers even if some of them fail.
6046 if (!Info.noteFailure())
6047 return false;
6048 Success = false;
6049 }
6050 }
6051 return Success;
6052}
6053
6054/// Perform a trivial copy from Param, which is the parameter of a copy or move
6055/// constructor or assignment operator.
6056static bool handleTrivialCopy(EvalInfo &Info, const ParmVarDecl *Param,
6057 const Expr *E, APValue &Result,
6058 bool CopyObjectRepresentation) {
6059 // Find the reference argument.
6060 CallStackFrame *Frame = Info.CurrentCall;
6061 APValue *RefValue = Info.getParamSlot(Frame->Arguments, Param);
6062 if (!RefValue) {
6063 Info.FFDiag(E);
6064 return false;
6065 }
6066
6067 // Copy out the contents of the RHS object.
6068 LValue RefLValue;
6069 RefLValue.setFrom(Info.Ctx, *RefValue);
6070 return handleLValueToRValueConversion(
6071 Info, E, Param->getType().getNonReferenceType(), RefLValue, Result,
6072 CopyObjectRepresentation);
6073}
6074
6075/// Evaluate a function call.
6076static bool HandleFunctionCall(SourceLocation CallLoc,
6077 const FunctionDecl *Callee, const LValue *This,
6078 ArrayRef<const Expr *> Args, CallRef Call,
6079 const Stmt *Body, EvalInfo &Info,
6080 APValue &Result, const LValue *ResultSlot) {
6081 if (!Info.CheckCallLimit(CallLoc))
6082 return false;
6083
6084 CallStackFrame Frame(Info, CallLoc, Callee, This, Call);
6085
6086 // For a trivial copy or move assignment, perform an APValue copy. This is
6087 // essential for unions, where the operations performed by the assignment
6088 // operator cannot be represented as statements.
6089 //
6090 // Skip this for non-union classes with no fields; in that case, the defaulted
6091 // copy/move does not actually read the object.
6092 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Callee);
6093 if (MD && MD->isDefaulted() &&
6094 (MD->getParent()->isUnion() ||
6095 (MD->isTrivial() &&
6096 isReadByLvalueToRvalueConversion(MD->getParent())))) {
6097 assert(This &&(static_cast <bool> (This && (MD->isCopyAssignmentOperator
() || MD->isMoveAssignmentOperator())) ? void (0) : __assert_fail
("This && (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6098, __extension__ __PRETTY_FUNCTION__))
6098 (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator()))(static_cast <bool> (This && (MD->isCopyAssignmentOperator
() || MD->isMoveAssignmentOperator())) ? void (0) : __assert_fail
("This && (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6098, __extension__ __PRETTY_FUNCTION__))
;
6099 APValue RHSValue;
6100 if (!handleTrivialCopy(Info, MD->getParamDecl(0), Args[0], RHSValue,
6101 MD->getParent()->isUnion()))
6102 return false;
6103 if (Info.getLangOpts().CPlusPlus20 && MD->isTrivial() &&
6104 !HandleUnionActiveMemberChange(Info, Args[0], *This))
6105 return false;
6106 if (!handleAssignment(Info, Args[0], *This, MD->getThisType(),
6107 RHSValue))
6108 return false;
6109 This->moveInto(Result);
6110 return true;
6111 } else if (MD && isLambdaCallOperator(MD)) {
6112 // We're in a lambda; determine the lambda capture field maps unless we're
6113 // just constexpr checking a lambda's call operator. constexpr checking is
6114 // done before the captures have been added to the closure object (unless
6115 // we're inferring constexpr-ness), so we don't have access to them in this
6116 // case. But since we don't need the captures to constexpr check, we can
6117 // just ignore them.
6118 if (!Info.checkingPotentialConstantExpression())
6119 MD->getParent()->getCaptureFields(Frame.LambdaCaptureFields,
6120 Frame.LambdaThisCaptureField);
6121 }
6122
6123 StmtResult Ret = {Result, ResultSlot};
6124 EvalStmtResult ESR = EvaluateStmt(Ret, Info, Body);
6125 if (ESR == ESR_Succeeded) {
6126 if (Callee->getReturnType()->isVoidType())
6127 return true;
6128 Info.FFDiag(Callee->getEndLoc(), diag::note_constexpr_no_return);
6129 }
6130 return ESR == ESR_Returned;
6131}
6132
6133/// Evaluate a constructor call.
6134static bool HandleConstructorCall(const Expr *E, const LValue &This,
6135 CallRef Call,
6136 const CXXConstructorDecl *Definition,
6137 EvalInfo &Info, APValue &Result) {
6138 SourceLocation CallLoc = E->getExprLoc();
6139 if (!Info.CheckCallLimit(CallLoc))
6140 return false;
6141
6142 const CXXRecordDecl *RD = Definition->getParent();
6143 if (RD->getNumVBases()) {
6144 Info.FFDiag(CallLoc, diag::note_constexpr_virtual_base) << RD;
6145 return false;
6146 }
6147
6148 EvalInfo::EvaluatingConstructorRAII EvalObj(
6149 Info,
6150 ObjectUnderConstruction{This.getLValueBase(), This.Designator.Entries},
6151 RD->getNumBases());
6152 CallStackFrame Frame(Info, CallLoc, Definition, &This, Call);
6153
6154 // FIXME: Creating an APValue just to hold a nonexistent return value is
6155 // wasteful.
6156 APValue RetVal;
6157 StmtResult Ret = {RetVal, nullptr};
6158
6159 // If it's a delegating constructor, delegate.
6160 if (Definition->isDelegatingConstructor()) {
6161 CXXConstructorDecl::init_const_iterator I = Definition->init_begin();
6162 if ((*I)->getInit()->isValueDependent()) {
6163 if (!EvaluateDependentExpr((*I)->getInit(), Info))
6164 return false;
6165 } else {
6166 FullExpressionRAII InitScope(Info);
6167 if (!EvaluateInPlace(Result, Info, This, (*I)->getInit()) ||
6168 !InitScope.destroy())
6169 return false;
6170 }
6171 return EvaluateStmt(Ret, Info, Definition->getBody()) != ESR_Failed;
6172 }
6173
6174 // For a trivial copy or move constructor, perform an APValue copy. This is
6175 // essential for unions (or classes with anonymous union members), where the
6176 // operations performed by the constructor cannot be represented by
6177 // ctor-initializers.
6178 //
6179 // Skip this for empty non-union classes; we should not perform an
6180 // lvalue-to-rvalue conversion on them because their copy constructor does not
6181 // actually read them.
6182 if (Definition->isDefaulted() && Definition->isCopyOrMoveConstructor() &&
6183 (Definition->getParent()->isUnion() ||
6184 (Definition->isTrivial() &&
6185 isReadByLvalueToRvalueConversion(Definition->getParent())))) {
6186 return handleTrivialCopy(Info, Definition->getParamDecl(0), E, Result,
6187 Definition->getParent()->isUnion());
6188 }
6189
6190 // Reserve space for the struct members.
6191 if (!Result.hasValue()) {
6192 if (!RD->isUnion())
6193 Result = APValue(APValue::UninitStruct(), RD->getNumBases(),
6194 std::distance(RD->field_begin(), RD->field_end()));
6195 else
6196 // A union starts with no active member.
6197 Result = APValue((const FieldDecl*)nullptr);
6198 }
6199
6200 if (RD->isInvalidDecl()) return false;
6201 const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
6202
6203 // A scope for temporaries lifetime-extended by reference members.
6204 BlockScopeRAII LifetimeExtendedScope(Info);
6205
6206 bool Success = true;
6207 unsigned BasesSeen = 0;
6208#ifndef NDEBUG
6209 CXXRecordDecl::base_class_const_iterator BaseIt = RD->bases_begin();
6210#endif
6211 CXXRecordDecl::field_iterator FieldIt = RD->field_begin();
6212 auto SkipToField = [&](FieldDecl *FD, bool Indirect) {
6213 // We might be initializing the same field again if this is an indirect
6214 // field initialization.
6215 if (FieldIt == RD->field_end() ||
6216 FieldIt->getFieldIndex() > FD->getFieldIndex()) {
6217 assert(Indirect && "fields out of order?")(static_cast <bool> (Indirect && "fields out of order?"
) ? void (0) : __assert_fail ("Indirect && \"fields out of order?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6217, __extension__ __PRETTY_FUNCTION__))
;
6218 return;
6219 }
6220
6221 // Default-initialize any fields with no explicit initializer.
6222 for (; !declaresSameEntity(*FieldIt, FD); ++FieldIt) {
6223 assert(FieldIt != RD->field_end() && "missing field?")(static_cast <bool> (FieldIt != RD->field_end() &&
"missing field?") ? void (0) : __assert_fail ("FieldIt != RD->field_end() && \"missing field?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6223, __extension__ __PRETTY_FUNCTION__))
;
6224 if (!FieldIt->isUnnamedBitfield())
6225 Success &= getDefaultInitValue(
6226 FieldIt->getType(),
6227 Result.getStructField(FieldIt->getFieldIndex()));
6228 }
6229 ++FieldIt;
6230 };
6231 for (const auto *I : Definition->inits()) {
6232 LValue Subobject = This;
6233 LValue SubobjectParent = This;
6234 APValue *Value = &Result;
6235
6236 // Determine the subobject to initialize.
6237 FieldDecl *FD = nullptr;
6238 if (I->isBaseInitializer()) {
6239 QualType BaseType(I->getBaseClass(), 0);
6240#ifndef NDEBUG
6241 // Non-virtual base classes are initialized in the order in the class
6242 // definition. We have already checked for virtual base classes.
6243 assert(!BaseIt->isVirtual() && "virtual base for literal type")(static_cast <bool> (!BaseIt->isVirtual() &&
"virtual base for literal type") ? void (0) : __assert_fail (
"!BaseIt->isVirtual() && \"virtual base for literal type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6243, __extension__ __PRETTY_FUNCTION__))
;
6244 assert(Info.Ctx.hasSameType(BaseIt->getType(), BaseType) &&(static_cast <bool> (Info.Ctx.hasSameType(BaseIt->getType
(), BaseType) && "base class initializers not in expected order"
) ? void (0) : __assert_fail ("Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && \"base class initializers not in expected order\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6245, __extension__ __PRETTY_FUNCTION__))
6245 "base class initializers not in expected order")(static_cast <bool> (Info.Ctx.hasSameType(BaseIt->getType
(), BaseType) && "base class initializers not in expected order"
) ? void (0) : __assert_fail ("Info.Ctx.hasSameType(BaseIt->getType(), BaseType) && \"base class initializers not in expected order\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6245, __extension__ __PRETTY_FUNCTION__))
;
6246 ++BaseIt;
6247#endif
6248 if (!HandleLValueDirectBase(Info, I->getInit(), Subobject, RD,
6249 BaseType->getAsCXXRecordDecl(), &Layout))
6250 return false;
6251 Value = &Result.getStructBase(BasesSeen++);
6252 } else if ((FD = I->getMember())) {
6253 if (!HandleLValueMember(Info, I->getInit(), Subobject, FD, &Layout))
6254 return false;
6255 if (RD->isUnion()) {
6256 Result = APValue(FD);
6257 Value = &Result.getUnionValue();
6258 } else {
6259 SkipToField(FD, false);
6260 Value = &Result.getStructField(FD->getFieldIndex());
6261 }
6262 } else if (IndirectFieldDecl *IFD = I->getIndirectMember()) {
6263 // Walk the indirect field decl's chain to find the object to initialize,
6264 // and make sure we've initialized every step along it.
6265 auto IndirectFieldChain = IFD->chain();
6266 for (auto *C : IndirectFieldChain) {
6267 FD = cast<FieldDecl>(C);
6268 CXXRecordDecl *CD = cast<CXXRecordDecl>(FD->getParent());
6269 // Switch the union field if it differs. This happens if we had
6270 // preceding zero-initialization, and we're now initializing a union
6271 // subobject other than the first.
6272 // FIXME: In this case, the values of the other subobjects are
6273 // specified, since zero-initialization sets all padding bits to zero.
6274 if (!Value->hasValue() ||
6275 (Value->isUnion() && Value->getUnionField() != FD)) {
6276 if (CD->isUnion())
6277 *Value = APValue(FD);
6278 else
6279 // FIXME: This immediately starts the lifetime of all members of
6280 // an anonymous struct. It would be preferable to strictly start
6281 // member lifetime in initialization order.
6282 Success &= getDefaultInitValue(Info.Ctx.getRecordType(CD), *Value);
6283 }
6284 // Store Subobject as its parent before updating it for the last element
6285 // in the chain.
6286 if (C == IndirectFieldChain.back())
6287 SubobjectParent = Subobject;
6288 if (!HandleLValueMember(Info, I->getInit(), Subobject, FD))
6289 return false;
6290 if (CD->isUnion())
6291 Value = &Value->getUnionValue();
6292 else {
6293 if (C == IndirectFieldChain.front() && !RD->isUnion())
6294 SkipToField(FD, true);
6295 Value = &Value->getStructField(FD->getFieldIndex());
6296 }
6297 }
6298 } else {
6299 llvm_unreachable("unknown base initializer kind")::llvm::llvm_unreachable_internal("unknown base initializer kind"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6299)
;
6300 }
6301
6302 // Need to override This for implicit field initializers as in this case
6303 // This refers to innermost anonymous struct/union containing initializer,
6304 // not to currently constructed class.
6305 const Expr *Init = I->getInit();
6306 if (Init->isValueDependent()) {
6307 if (!EvaluateDependentExpr(Init, Info))
6308 return false;
6309 } else {
6310 ThisOverrideRAII ThisOverride(*Info.CurrentCall, &SubobjectParent,
6311 isa<CXXDefaultInitExpr>(Init));
6312 FullExpressionRAII InitScope(Info);
6313 if (!EvaluateInPlace(*Value, Info, Subobject, Init) ||
6314 (FD && FD->isBitField() &&
6315 !truncateBitfieldValue(Info, Init, *Value, FD))) {
6316 // If we're checking for a potential constant expression, evaluate all
6317 // initializers even if some of them fail.
6318 if (!Info.noteFailure())
6319 return false;
6320 Success = false;
6321 }
6322 }
6323
6324 // This is the point at which the dynamic type of the object becomes this
6325 // class type.
6326 if (I->isBaseInitializer() && BasesSeen == RD->getNumBases())
6327 EvalObj.finishedConstructingBases();
6328 }
6329
6330 // Default-initialize any remaining fields.
6331 if (!RD->isUnion()) {
6332 for (; FieldIt != RD->field_end(); ++FieldIt) {
6333 if (!FieldIt->isUnnamedBitfield())
6334 Success &= getDefaultInitValue(
6335 FieldIt->getType(),
6336 Result.getStructField(FieldIt->getFieldIndex()));
6337 }
6338 }
6339
6340 EvalObj.finishedConstructingFields();
6341
6342 return Success &&
6343 EvaluateStmt(Ret, Info, Definition->getBody()) != ESR_Failed &&
6344 LifetimeExtendedScope.destroy();
6345}
6346
6347static bool HandleConstructorCall(const Expr *E, const LValue &This,
6348 ArrayRef<const Expr*> Args,
6349 const CXXConstructorDecl *Definition,
6350 EvalInfo &Info, APValue &Result) {
6351 CallScopeRAII CallScope(Info);
6352 CallRef Call = Info.CurrentCall->createCall(Definition);
6353 if (!EvaluateArgs(Args, Call, Info, Definition))
6354 return false;
6355
6356 return HandleConstructorCall(E, This, Call, Definition, Info, Result) &&
6357 CallScope.destroy();
6358}
6359
6360static bool HandleDestructionImpl(EvalInfo &Info, SourceLocation CallLoc,
6361 const LValue &This, APValue &Value,
6362 QualType T) {
6363 // Objects can only be destroyed while they're within their lifetimes.
6364 // FIXME: We have no representation for whether an object of type nullptr_t
6365 // is in its lifetime; it usually doesn't matter. Perhaps we should model it
6366 // as indeterminate instead?
6367 if (Value.isAbsent() && !T->isNullPtrType()) {
6368 APValue Printable;
6369 This.moveInto(Printable);
6370 Info.FFDiag(CallLoc, diag::note_constexpr_destroy_out_of_lifetime)
6371 << Printable.getAsString(Info.Ctx, Info.Ctx.getLValueReferenceType(T));
6372 return false;
6373 }
6374
6375 // Invent an expression for location purposes.
6376 // FIXME: We shouldn't need to do this.
6377 OpaqueValueExpr LocE(CallLoc, Info.Ctx.IntTy, VK_PRValue);
6378
6379 // For arrays, destroy elements right-to-left.
6380 if (const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(T)) {
6381 uint64_t Size = CAT->getSize().getZExtValue();
6382 QualType ElemT = CAT->getElementType();
6383
6384 LValue ElemLV = This;
6385 ElemLV.addArray(Info, &LocE, CAT);
6386 if (!HandleLValueArrayAdjustment(Info, &LocE, ElemLV, ElemT, Size))
6387 return false;
6388
6389 // Ensure that we have actual array elements available to destroy; the
6390 // destructors might mutate the value, so we can't run them on the array
6391 // filler.
6392 if (Size && Size > Value.getArrayInitializedElts())
6393 expandArray(Value, Value.getArraySize() - 1);
6394
6395 for (; Size != 0; --Size) {
6396 APValue &Elem = Value.getArrayInitializedElt(Size - 1);
6397 if (!HandleLValueArrayAdjustment(Info, &LocE, ElemLV, ElemT, -1) ||
6398 !HandleDestructionImpl(Info, CallLoc, ElemLV, Elem, ElemT))
6399 return false;
6400 }
6401
6402 // End the lifetime of this array now.
6403 Value = APValue();
6404 return true;
6405 }
6406
6407 const CXXRecordDecl *RD = T->getAsCXXRecordDecl();
6408 if (!RD) {
6409 if (T.isDestructedType()) {
6410 Info.FFDiag(CallLoc, diag::note_constexpr_unsupported_destruction) << T;
6411 return false;
6412 }
6413
6414 Value = APValue();
6415 return true;
6416 }
6417
6418 if (RD->getNumVBases()) {
6419 Info.FFDiag(CallLoc, diag::note_constexpr_virtual_base) << RD;
6420 return false;
6421 }
6422
6423 const CXXDestructorDecl *DD = RD->getDestructor();
6424 if (!DD && !RD->hasTrivialDestructor()) {
6425 Info.FFDiag(CallLoc);
6426 return false;
6427 }
6428
6429 if (!DD || DD->isTrivial() ||
6430 (RD->isAnonymousStructOrUnion() && RD->isUnion())) {
6431 // A trivial destructor just ends the lifetime of the object. Check for
6432 // this case before checking for a body, because we might not bother
6433 // building a body for a trivial destructor. Note that it doesn't matter
6434 // whether the destructor is constexpr in this case; all trivial
6435 // destructors are constexpr.
6436 //
6437 // If an anonymous union would be destroyed, some enclosing destructor must
6438 // have been explicitly defined, and the anonymous union destruction should
6439 // have no effect.
6440 Value = APValue();
6441 return true;
6442 }
6443
6444 if (!Info.CheckCallLimit(CallLoc))
6445 return false;
6446
6447 const FunctionDecl *Definition = nullptr;
6448 const Stmt *Body = DD->getBody(Definition);
6449
6450 if (!CheckConstexprFunction(Info, CallLoc, DD, Definition, Body))
6451 return false;
6452
6453 CallStackFrame Frame(Info, CallLoc, Definition, &This, CallRef());
6454
6455 // We're now in the period of destruction of this object.
6456 unsigned BasesLeft = RD->getNumBases();
6457 EvalInfo::EvaluatingDestructorRAII EvalObj(
6458 Info,
6459 ObjectUnderConstruction{This.getLValueBase(), This.Designator.Entries});
6460 if (!EvalObj.DidInsert) {
6461 // C++2a [class.dtor]p19:
6462 // the behavior is undefined if the destructor is invoked for an object
6463 // whose lifetime has ended
6464 // (Note that formally the lifetime ends when the period of destruction
6465 // begins, even though certain uses of the object remain valid until the
6466 // period of destruction ends.)
6467 Info.FFDiag(CallLoc, diag::note_constexpr_double_destroy);
6468 return false;
6469 }
6470
6471 // FIXME: Creating an APValue just to hold a nonexistent return value is
6472 // wasteful.
6473 APValue RetVal;
6474 StmtResult Ret = {RetVal, nullptr};
6475 if (EvaluateStmt(Ret, Info, Definition->getBody()) == ESR_Failed)
6476 return false;
6477
6478 // A union destructor does not implicitly destroy its members.
6479 if (RD->isUnion())
6480 return true;
6481
6482 const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
6483
6484 // We don't have a good way to iterate fields in reverse, so collect all the
6485 // fields first and then walk them backwards.
6486 SmallVector<FieldDecl*, 16> Fields(RD->field_begin(), RD->field_end());
6487 for (const FieldDecl *FD : llvm::reverse(Fields)) {
6488 if (FD->isUnnamedBitfield())
6489 continue;
6490
6491 LValue Subobject = This;
6492 if (!HandleLValueMember(Info, &LocE, Subobject, FD, &Layout))
6493 return false;
6494
6495 APValue *SubobjectValue = &Value.getStructField(FD->getFieldIndex());
6496 if (!HandleDestructionImpl(Info, CallLoc, Subobject, *SubobjectValue,
6497 FD->getType()))
6498 return false;
6499 }
6500
6501 if (BasesLeft != 0)
6502 EvalObj.startedDestroyingBases();
6503
6504 // Destroy base classes in reverse order.
6505 for (const CXXBaseSpecifier &Base : llvm::reverse(RD->bases())) {
6506 --BasesLeft;
6507
6508 QualType BaseType = Base.getType();
6509 LValue Subobject = This;
6510 if (!HandleLValueDirectBase(Info, &LocE, Subobject, RD,
6511 BaseType->getAsCXXRecordDecl(), &Layout))
6512 return false;
6513
6514 APValue *SubobjectValue = &Value.getStructBase(BasesLeft);
6515 if (!HandleDestructionImpl(Info, CallLoc, Subobject, *SubobjectValue,
6516 BaseType))
6517 return false;
6518 }
6519 assert(BasesLeft == 0 && "NumBases was wrong?")(static_cast <bool> (BasesLeft == 0 && "NumBases was wrong?"
) ? void (0) : __assert_fail ("BasesLeft == 0 && \"NumBases was wrong?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6519, __extension__ __PRETTY_FUNCTION__))
;
6520
6521 // The period of destruction ends now. The object is gone.
6522 Value = APValue();
6523 return true;
6524}
6525
6526namespace {
6527struct DestroyObjectHandler {
6528 EvalInfo &Info;
6529 const Expr *E;
6530 const LValue &This;
6531 const AccessKinds AccessKind;
6532
6533 typedef bool result_type;
6534 bool failed() { return false; }
6535 bool found(APValue &Subobj, QualType SubobjType) {
6536 return HandleDestructionImpl(Info, E->getExprLoc(), This, Subobj,
6537 SubobjType);
6538 }
6539 bool found(APSInt &Value, QualType SubobjType) {
6540 Info.FFDiag(E, diag::note_constexpr_destroy_complex_elem);
6541 return false;
6542 }
6543 bool found(APFloat &Value, QualType SubobjType) {
6544 Info.FFDiag(E, diag::note_constexpr_destroy_complex_elem);
6545 return false;
6546 }
6547};
6548}
6549
6550/// Perform a destructor or pseudo-destructor call on the given object, which
6551/// might in general not be a complete object.
6552static bool HandleDestruction(EvalInfo &Info, const Expr *E,
6553 const LValue &This, QualType ThisType) {
6554 CompleteObject Obj = findCompleteObject(Info, E, AK_Destroy, This, ThisType);
6555 DestroyObjectHandler Handler = {Info, E, This, AK_Destroy};
6556 return Obj && findSubobject(Info, E, Obj, This.Designator, Handler);
6557}
6558
6559/// Destroy and end the lifetime of the given complete object.
6560static bool HandleDestruction(EvalInfo &Info, SourceLocation Loc,
6561 APValue::LValueBase LVBase, APValue &Value,
6562 QualType T) {
6563 // If we've had an unmodeled side-effect, we can't rely on mutable state
6564 // (such as the object we're about to destroy) being correct.
6565 if (Info.EvalStatus.HasSideEffects)
6566 return false;
6567
6568 LValue LV;
6569 LV.set({LVBase});
6570 return HandleDestructionImpl(Info, Loc, LV, Value, T);
6571}
6572
6573/// Perform a call to 'perator new' or to `__builtin_operator_new'.
6574static bool HandleOperatorNewCall(EvalInfo &Info, const CallExpr *E,
6575 LValue &Result) {
6576 if (Info.checkingPotentialConstantExpression() ||
6577 Info.SpeculativeEvaluationDepth)
6578 return false;
6579
6580 // This is permitted only within a call to std::allocator<T>::allocate.
6581 auto Caller = Info.getStdAllocatorCaller("allocate");
6582 if (!Caller) {
6583 Info.FFDiag(E->getExprLoc(), Info.getLangOpts().CPlusPlus20
6584 ? diag::note_constexpr_new_untyped
6585 : diag::note_constexpr_new);
6586 return false;
6587 }
6588
6589 QualType ElemType = Caller.ElemType;
6590 if (ElemType->isIncompleteType() || ElemType->isFunctionType()) {
6591 Info.FFDiag(E->getExprLoc(),
6592 diag::note_constexpr_new_not_complete_object_type)
6593 << (ElemType->isIncompleteType() ? 0 : 1) << ElemType;
6594 return false;
6595 }
6596
6597 APSInt ByteSize;
6598 if (!EvaluateInteger(E->getArg(0), ByteSize, Info))
6599 return false;
6600 bool IsNothrow = false;
6601 for (unsigned I = 1, N = E->getNumArgs(); I != N; ++I) {
6602 EvaluateIgnoredValue(Info, E->getArg(I));
6603 IsNothrow |= E->getType()->isNothrowT();
6604 }
6605
6606 CharUnits ElemSize;
6607 if (!HandleSizeof(Info, E->getExprLoc(), ElemType, ElemSize))
6608 return false;
6609 APInt Size, Remainder;
6610 APInt ElemSizeAP(ByteSize.getBitWidth(), ElemSize.getQuantity());
6611 APInt::udivrem(ByteSize, ElemSizeAP, Size, Remainder);
6612 if (Remainder != 0) {
6613 // This likely indicates a bug in the implementation of 'std::allocator'.
6614 Info.FFDiag(E->getExprLoc(), diag::note_constexpr_operator_new_bad_size)
6615 << ByteSize << APSInt(ElemSizeAP, true) << ElemType;
6616 return false;
6617 }
6618
6619 if (ByteSize.getActiveBits() > ConstantArrayType::getMaxSizeBits(Info.Ctx)) {
6620 if (IsNothrow) {
6621 Result.setNull(Info.Ctx, E->getType());
6622 return true;
6623 }
6624
6625 Info.FFDiag(E, diag::note_constexpr_new_too_large) << APSInt(Size, true);
6626 return false;
6627 }
6628
6629 QualType AllocType = Info.Ctx.getConstantArrayType(ElemType, Size, nullptr,
6630 ArrayType::Normal, 0);
6631 APValue *Val = Info.createHeapAlloc(E, AllocType, Result);
6632 *Val = APValue(APValue::UninitArray(), 0, Size.getZExtValue());
6633 Result.addArray(Info, E, cast<ConstantArrayType>(AllocType));
6634 return true;
6635}
6636
6637static bool hasVirtualDestructor(QualType T) {
6638 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
6639 if (CXXDestructorDecl *DD = RD->getDestructor())
6640 return DD->isVirtual();
6641 return false;
6642}
6643
6644static const FunctionDecl *getVirtualOperatorDelete(QualType T) {
6645 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
6646 if (CXXDestructorDecl *DD = RD->getDestructor())
6647 return DD->isVirtual() ? DD->getOperatorDelete() : nullptr;
6648 return nullptr;
6649}
6650
6651/// Check that the given object is a suitable pointer to a heap allocation that
6652/// still exists and is of the right kind for the purpose of a deletion.
6653///
6654/// On success, returns the heap allocation to deallocate. On failure, produces
6655/// a diagnostic and returns None.
6656static Optional<DynAlloc *> CheckDeleteKind(EvalInfo &Info, const Expr *E,
6657 const LValue &Pointer,
6658 DynAlloc::Kind DeallocKind) {
6659 auto PointerAsString = [&] {
6660 return Pointer.toString(Info.Ctx, Info.Ctx.VoidPtrTy);
6661 };
6662
6663 DynamicAllocLValue DA = Pointer.Base.dyn_cast<DynamicAllocLValue>();
6664 if (!DA) {
6665 Info.FFDiag(E, diag::note_constexpr_delete_not_heap_alloc)
6666 << PointerAsString();
6667 if (Pointer.Base)
6668 NoteLValueLocation(Info, Pointer.Base);
6669 return None;
6670 }
6671
6672 Optional<DynAlloc *> Alloc = Info.lookupDynamicAlloc(DA);
6673 if (!Alloc) {
6674 Info.FFDiag(E, diag::note_constexpr_double_delete);
6675 return None;
6676 }
6677
6678 QualType AllocType = Pointer.Base.getDynamicAllocType();
6679 if (DeallocKind != (*Alloc)->getKind()) {
6680 Info.FFDiag(E, diag::note_constexpr_new_delete_mismatch)
6681 << DeallocKind << (*Alloc)->getKind() << AllocType;
6682 NoteLValueLocation(Info, Pointer.Base);
6683 return None;
6684 }
6685
6686 bool Subobject = false;
6687 if (DeallocKind == DynAlloc::New) {
6688 Subobject = Pointer.Designator.MostDerivedPathLength != 0 ||
6689 Pointer.Designator.isOnePastTheEnd();
6690 } else {
6691 Subobject = Pointer.Designator.Entries.size() != 1 ||
6692 Pointer.Designator.Entries[0].getAsArrayIndex() != 0;
6693 }
6694 if (Subobject) {
6695 Info.FFDiag(E, diag::note_constexpr_delete_subobject)
6696 << PointerAsString() << Pointer.Designator.isOnePastTheEnd();
6697 return None;
6698 }
6699
6700 return Alloc;
6701}
6702
6703// Perform a call to 'operator delete' or '__builtin_operator_delete'.
6704bool HandleOperatorDeleteCall(EvalInfo &Info, const CallExpr *E) {
6705 if (Info.checkingPotentialConstantExpression() ||
6706 Info.SpeculativeEvaluationDepth)
6707 return false;
6708
6709 // This is permitted only within a call to std::allocator<T>::deallocate.
6710 if (!Info.getStdAllocatorCaller("deallocate")) {
6711 Info.FFDiag(E->getExprLoc());
6712 return true;
6713 }
6714
6715 LValue Pointer;
6716 if (!EvaluatePointer(E->getArg(0), Pointer, Info))
6717 return false;
6718 for (unsigned I = 1, N = E->getNumArgs(); I != N; ++I)
6719 EvaluateIgnoredValue(Info, E->getArg(I));
6720
6721 if (Pointer.Designator.Invalid)
6722 return false;
6723
6724 // Deleting a null pointer would have no effect, but it's not permitted by
6725 // std::allocator<T>::deallocate's contract.
6726 if (Pointer.isNullPointer()) {
6727 Info.CCEDiag(E->getExprLoc(), diag::note_constexpr_deallocate_null);
6728 return true;
6729 }
6730
6731 if (!CheckDeleteKind(Info, E, Pointer, DynAlloc::StdAllocator))
6732 return false;
6733
6734 Info.HeapAllocs.erase(Pointer.Base.get<DynamicAllocLValue>());
6735 return true;
6736}
6737
6738//===----------------------------------------------------------------------===//
6739// Generic Evaluation
6740//===----------------------------------------------------------------------===//
6741namespace {
6742
6743class BitCastBuffer {
6744 // FIXME: We're going to need bit-level granularity when we support
6745 // bit-fields.
6746 // FIXME: Its possible under the C++ standard for 'char' to not be 8 bits, but
6747 // we don't support a host or target where that is the case. Still, we should
6748 // use a more generic type in case we ever do.
6749 SmallVector<Optional<unsigned char>, 32> Bytes;
6750
6751 static_assert(std::numeric_limits<unsigned char>::digits >= 8,
6752 "Need at least 8 bit unsigned char");
6753
6754 bool TargetIsLittleEndian;
6755
6756public:
6757 BitCastBuffer(CharUnits Width, bool TargetIsLittleEndian)
6758 : Bytes(Width.getQuantity()),
6759 TargetIsLittleEndian(TargetIsLittleEndian) {}
6760
6761 LLVM_NODISCARD[[clang::warn_unused_result]]
6762 bool readObject(CharUnits Offset, CharUnits Width,
6763 SmallVectorImpl<unsigned char> &Output) const {
6764 for (CharUnits I = Offset, E = Offset + Width; I != E; ++I) {
6765 // If a byte of an integer is uninitialized, then the whole integer is
6766 // uninitialized.
6767 if (!Bytes[I.getQuantity()])
6768 return false;
6769 Output.push_back(*Bytes[I.getQuantity()]);
6770 }
6771 if (llvm::sys::IsLittleEndianHost != TargetIsLittleEndian)
6772 std::reverse(Output.begin(), Output.end());
6773 return true;
6774 }
6775
6776 void writeObject(CharUnits Offset, SmallVectorImpl<unsigned char> &Input) {
6777 if (llvm::sys::IsLittleEndianHost != TargetIsLittleEndian)
6778 std::reverse(Input.begin(), Input.end());
6779
6780 size_t Index = 0;
6781 for (unsigned char Byte : Input) {
6782 assert(!Bytes[Offset.getQuantity() + Index] && "overwriting a byte?")(static_cast <bool> (!Bytes[Offset.getQuantity() + Index
] && "overwriting a byte?") ? void (0) : __assert_fail
("!Bytes[Offset.getQuantity() + Index] && \"overwriting a byte?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6782, __extension__ __PRETTY_FUNCTION__))
;
6783 Bytes[Offset.getQuantity() + Index] = Byte;
6784 ++Index;
6785 }
6786 }
6787
6788 size_t size() { return Bytes.size(); }
6789};
6790
6791/// Traverse an APValue to produce an BitCastBuffer, emulating how the current
6792/// target would represent the value at runtime.
6793class APValueToBufferConverter {
6794 EvalInfo &Info;
6795 BitCastBuffer Buffer;
6796 const CastExpr *BCE;
6797
6798 APValueToBufferConverter(EvalInfo &Info, CharUnits ObjectWidth,
6799 const CastExpr *BCE)
6800 : Info(Info),
6801 Buffer(ObjectWidth, Info.Ctx.getTargetInfo().isLittleEndian()),
6802 BCE(BCE) {}
6803
6804 bool visit(const APValue &Val, QualType Ty) {
6805 return visit(Val, Ty, CharUnits::fromQuantity(0));
6806 }
6807
6808 // Write out Val with type Ty into Buffer starting at Offset.
6809 bool visit(const APValue &Val, QualType Ty, CharUnits Offset) {
6810 assert((size_t)Offset.getQuantity() <= Buffer.size())(static_cast <bool> ((size_t)Offset.getQuantity() <=
Buffer.size()) ? void (0) : __assert_fail ("(size_t)Offset.getQuantity() <= Buffer.size()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6810, __extension__ __PRETTY_FUNCTION__))
;
6811
6812 // As a special case, nullptr_t has an indeterminate value.
6813 if (Ty->isNullPtrType())
6814 return true;
6815
6816 // Dig through Src to find the byte at SrcOffset.
6817 switch (Val.getKind()) {
6818 case APValue::Indeterminate:
6819 case APValue::None:
6820 return true;
6821
6822 case APValue::Int:
6823 return visitInt(Val.getInt(), Ty, Offset);
6824 case APValue::Float:
6825 return visitFloat(Val.getFloat(), Ty, Offset);
6826 case APValue::Array:
6827 return visitArray(Val, Ty, Offset);
6828 case APValue::Struct:
6829 return visitRecord(Val, Ty, Offset);
6830
6831 case APValue::ComplexInt:
6832 case APValue::ComplexFloat:
6833 case APValue::Vector:
6834 case APValue::FixedPoint:
6835 // FIXME: We should support these.
6836
6837 case APValue::Union:
6838 case APValue::MemberPointer:
6839 case APValue::AddrLabelDiff: {
6840 Info.FFDiag(BCE->getBeginLoc(),
6841 diag::note_constexpr_bit_cast_unsupported_type)
6842 << Ty;
6843 return false;
6844 }
6845
6846 case APValue::LValue:
6847 llvm_unreachable("LValue subobject in bit_cast?")::llvm::llvm_unreachable_internal("LValue subobject in bit_cast?"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6847)
;
6848 }
6849 llvm_unreachable("Unhandled APValue::ValueKind")::llvm::llvm_unreachable_internal("Unhandled APValue::ValueKind"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6849)
;
6850 }
6851
6852 bool visitRecord(const APValue &Val, QualType Ty, CharUnits Offset) {
6853 const RecordDecl *RD = Ty->getAsRecordDecl();
6854 const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
6855
6856 // Visit the base classes.
6857 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
6858 for (size_t I = 0, E = CXXRD->getNumBases(); I != E; ++I) {
6859 const CXXBaseSpecifier &BS = CXXRD->bases_begin()[I];
6860 CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
6861
6862 if (!visitRecord(Val.getStructBase(I), BS.getType(),
6863 Layout.getBaseClassOffset(BaseDecl) + Offset))
6864 return false;
6865 }
6866 }
6867
6868 // Visit the fields.
6869 unsigned FieldIdx = 0;
6870 for (FieldDecl *FD : RD->fields()) {
6871 if (FD->isBitField()) {
6872 Info.FFDiag(BCE->getBeginLoc(),
6873 diag::note_constexpr_bit_cast_unsupported_bitfield);
6874 return false;
6875 }
6876
6877 uint64_t FieldOffsetBits = Layout.getFieldOffset(FieldIdx);
6878
6879 assert(FieldOffsetBits % Info.Ctx.getCharWidth() == 0 &&(static_cast <bool> (FieldOffsetBits % Info.Ctx.getCharWidth
() == 0 && "only bit-fields can have sub-char alignment"
) ? void (0) : __assert_fail ("FieldOffsetBits % Info.Ctx.getCharWidth() == 0 && \"only bit-fields can have sub-char alignment\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6880, __extension__ __PRETTY_FUNCTION__))
6880 "only bit-fields can have sub-char alignment")(static_cast <bool> (FieldOffsetBits % Info.Ctx.getCharWidth
() == 0 && "only bit-fields can have sub-char alignment"
) ? void (0) : __assert_fail ("FieldOffsetBits % Info.Ctx.getCharWidth() == 0 && \"only bit-fields can have sub-char alignment\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6880, __extension__ __PRETTY_FUNCTION__))
;
6881 CharUnits FieldOffset =
6882 Info.Ctx.toCharUnitsFromBits(FieldOffsetBits) + Offset;
6883 QualType FieldTy = FD->getType();
6884 if (!visit(Val.getStructField(FieldIdx), FieldTy, FieldOffset))
6885 return false;
6886 ++FieldIdx;
6887 }
6888
6889 return true;
6890 }
6891
6892 bool visitArray(const APValue &Val, QualType Ty, CharUnits Offset) {
6893 const auto *CAT =
6894 dyn_cast_or_null<ConstantArrayType>(Ty->getAsArrayTypeUnsafe());
6895 if (!CAT)
6896 return false;
6897
6898 CharUnits ElemWidth = Info.Ctx.getTypeSizeInChars(CAT->getElementType());
6899 unsigned NumInitializedElts = Val.getArrayInitializedElts();
6900 unsigned ArraySize = Val.getArraySize();
6901 // First, initialize the initialized elements.
6902 for (unsigned I = 0; I != NumInitializedElts; ++I) {
6903 const APValue &SubObj = Val.getArrayInitializedElt(I);
6904 if (!visit(SubObj, CAT->getElementType(), Offset + I * ElemWidth))
6905 return false;
6906 }
6907
6908 // Next, initialize the rest of the array using the filler.
6909 if (Val.hasArrayFiller()) {
6910 const APValue &Filler = Val.getArrayFiller();
6911 for (unsigned I = NumInitializedElts; I != ArraySize; ++I) {
6912 if (!visit(Filler, CAT->getElementType(), Offset + I * ElemWidth))
6913 return false;
6914 }
6915 }
6916
6917 return true;
6918 }
6919
6920 bool visitInt(const APSInt &Val, QualType Ty, CharUnits Offset) {
6921 APSInt AdjustedVal = Val;
6922 unsigned Width = AdjustedVal.getBitWidth();
6923 if (Ty->isBooleanType()) {
6924 Width = Info.Ctx.getTypeSize(Ty);
6925 AdjustedVal = AdjustedVal.extend(Width);
6926 }
6927
6928 SmallVector<unsigned char, 8> Bytes(Width / 8);
6929 llvm::StoreIntToMemory(AdjustedVal, &*Bytes.begin(), Width / 8);
6930 Buffer.writeObject(Offset, Bytes);
6931 return true;
6932 }
6933
6934 bool visitFloat(const APFloat &Val, QualType Ty, CharUnits Offset) {
6935 APSInt AsInt(Val.bitcastToAPInt());
6936 return visitInt(AsInt, Ty, Offset);
6937 }
6938
6939public:
6940 static Optional<BitCastBuffer> convert(EvalInfo &Info, const APValue &Src,
6941 const CastExpr *BCE) {
6942 CharUnits DstSize = Info.Ctx.getTypeSizeInChars(BCE->getType());
6943 APValueToBufferConverter Converter(Info, DstSize, BCE);
6944 if (!Converter.visit(Src, BCE->getSubExpr()->getType()))
6945 return None;
6946 return Converter.Buffer;
6947 }
6948};
6949
6950/// Write an BitCastBuffer into an APValue.
6951class BufferToAPValueConverter {
6952 EvalInfo &Info;
6953 const BitCastBuffer &Buffer;
6954 const CastExpr *BCE;
6955
6956 BufferToAPValueConverter(EvalInfo &Info, const BitCastBuffer &Buffer,
6957 const CastExpr *BCE)
6958 : Info(Info), Buffer(Buffer), BCE(BCE) {}
6959
6960 // Emit an unsupported bit_cast type error. Sema refuses to build a bit_cast
6961 // with an invalid type, so anything left is a deficiency on our part (FIXME).
6962 // Ideally this will be unreachable.
6963 llvm::NoneType unsupportedType(QualType Ty) {
6964 Info.FFDiag(BCE->getBeginLoc(),
6965 diag::note_constexpr_bit_cast_unsupported_type)
6966 << Ty;
6967 return None;
6968 }
6969
6970 llvm::NoneType unrepresentableValue(QualType Ty, const APSInt &Val) {
6971 Info.FFDiag(BCE->getBeginLoc(),
6972 diag::note_constexpr_bit_cast_unrepresentable_value)
6973 << Ty << toString(Val, /*Radix=*/10);
6974 return None;
6975 }
6976
6977 Optional<APValue> visit(const BuiltinType *T, CharUnits Offset,
6978 const EnumType *EnumSugar = nullptr) {
6979 if (T->isNullPtrType()) {
6980 uint64_t NullValue = Info.Ctx.getTargetNullPointerValue(QualType(T, 0));
6981 return APValue((Expr *)nullptr,
6982 /*Offset=*/CharUnits::fromQuantity(NullValue),
6983 APValue::NoLValuePath{}, /*IsNullPtr=*/true);
6984 }
6985
6986 CharUnits SizeOf = Info.Ctx.getTypeSizeInChars(T);
6987
6988 // Work around floating point types that contain unused padding bytes. This
6989 // is really just `long double` on x86, which is the only fundamental type
6990 // with padding bytes.
6991 if (T->isRealFloatingType()) {
6992 const llvm::fltSemantics &Semantics =
6993 Info.Ctx.getFloatTypeSemantics(QualType(T, 0));
6994 unsigned NumBits = llvm::APFloatBase::getSizeInBits(Semantics);
6995 assert(NumBits % 8 == 0)(static_cast <bool> (NumBits % 8 == 0) ? void (0) : __assert_fail
("NumBits % 8 == 0", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 6995, __extension__ __PRETTY_FUNCTION__))
;
6996 CharUnits NumBytes = CharUnits::fromQuantity(NumBits / 8);
6997 if (NumBytes != SizeOf)
6998 SizeOf = NumBytes;
6999 }
7000
7001 SmallVector<uint8_t, 8> Bytes;
7002 if (!Buffer.readObject(Offset, SizeOf, Bytes)) {
7003 // If this is std::byte or unsigned char, then its okay to store an
7004 // indeterminate value.
7005 bool IsStdByte = EnumSugar && EnumSugar->isStdByteType();
7006 bool IsUChar =
7007 !EnumSugar && (T->isSpecificBuiltinType(BuiltinType::UChar) ||
7008 T->isSpecificBuiltinType(BuiltinType::Char_U));
7009 if (!IsStdByte && !IsUChar) {
7010 QualType DisplayType(EnumSugar ? (const Type *)EnumSugar : T, 0);
7011 Info.FFDiag(BCE->getExprLoc(),
7012 diag::note_constexpr_bit_cast_indet_dest)
7013 << DisplayType << Info.Ctx.getLangOpts().CharIsSigned;
7014 return None;
7015 }
7016
7017 return APValue::IndeterminateValue();
7018 }
7019
7020 APSInt Val(SizeOf.getQuantity() * Info.Ctx.getCharWidth(), true);
7021 llvm::LoadIntFromMemory(Val, &*Bytes.begin(), Bytes.size());
7022
7023 if (T->isIntegralOrEnumerationType()) {
7024 Val.setIsSigned(T->isSignedIntegerOrEnumerationType());
7025
7026 unsigned IntWidth = Info.Ctx.getIntWidth(QualType(T, 0));
7027 if (IntWidth != Val.getBitWidth()) {
7028 APSInt Truncated = Val.trunc(IntWidth);
7029 if (Truncated.extend(Val.getBitWidth()) != Val)
7030 return unrepresentableValue(QualType(T, 0), Val);
7031 Val = Truncated;
7032 }
7033
7034 return APValue(Val);
7035 }
7036
7037 if (T->isRealFloatingType()) {
7038 const llvm::fltSemantics &Semantics =
7039 Info.Ctx.getFloatTypeSemantics(QualType(T, 0));
7040 return APValue(APFloat(Semantics, Val));
7041 }
7042
7043 return unsupportedType(QualType(T, 0));
7044 }
7045
7046 Optional<APValue> visit(const RecordType *RTy, CharUnits Offset) {
7047 const RecordDecl *RD = RTy->getAsRecordDecl();
7048 const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
7049
7050 unsigned NumBases = 0;
7051 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD))
7052 NumBases = CXXRD->getNumBases();
7053
7054 APValue ResultVal(APValue::UninitStruct(), NumBases,
7055 std::distance(RD->field_begin(), RD->field_end()));
7056
7057 // Visit the base classes.
7058 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
7059 for (size_t I = 0, E = CXXRD->getNumBases(); I != E; ++I) {
7060 const CXXBaseSpecifier &BS = CXXRD->bases_begin()[I];
7061 CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
7062 if (BaseDecl->isEmpty() ||
7063 Info.Ctx.getASTRecordLayout(BaseDecl).getNonVirtualSize().isZero())
7064 continue;
7065
7066 Optional<APValue> SubObj = visitType(
7067 BS.getType(), Layout.getBaseClassOffset(BaseDecl) + Offset);
7068 if (!SubObj)
7069 return None;
7070 ResultVal.getStructBase(I) = *SubObj;
7071 }
7072 }
7073
7074 // Visit the fields.
7075 unsigned FieldIdx = 0;
7076 for (FieldDecl *FD : RD->fields()) {
7077 // FIXME: We don't currently support bit-fields. A lot of the logic for
7078 // this is in CodeGen, so we need to factor it around.
7079 if (FD->isBitField()) {
7080 Info.FFDiag(BCE->getBeginLoc(),
7081 diag::note_constexpr_bit_cast_unsupported_bitfield);
7082 return None;
7083 }
7084
7085 uint64_t FieldOffsetBits = Layout.getFieldOffset(FieldIdx);
7086 assert(FieldOffsetBits % Info.Ctx.getCharWidth() == 0)(static_cast <bool> (FieldOffsetBits % Info.Ctx.getCharWidth
() == 0) ? void (0) : __assert_fail ("FieldOffsetBits % Info.Ctx.getCharWidth() == 0"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7086, __extension__ __PRETTY_FUNCTION__))
;
7087
7088 CharUnits FieldOffset =
7089 CharUnits::fromQuantity(FieldOffsetBits / Info.Ctx.getCharWidth()) +
7090 Offset;
7091 QualType FieldTy = FD->getType();
7092 Optional<APValue> SubObj = visitType(FieldTy, FieldOffset);
7093 if (!SubObj)
7094 return None;
7095 ResultVal.getStructField(FieldIdx) = *SubObj;
7096 ++FieldIdx;
7097 }
7098
7099 return ResultVal;
7100 }
7101
7102 Optional<APValue> visit(const EnumType *Ty, CharUnits Offset) {
7103 QualType RepresentationType = Ty->getDecl()->getIntegerType();
7104 assert(!RepresentationType.isNull() &&(static_cast <bool> (!RepresentationType.isNull() &&
"enum forward decl should be caught by Sema") ? void (0) : __assert_fail
("!RepresentationType.isNull() && \"enum forward decl should be caught by Sema\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7105, __extension__ __PRETTY_FUNCTION__))
7105 "enum forward decl should be caught by Sema")(static_cast <bool> (!RepresentationType.isNull() &&
"enum forward decl should be caught by Sema") ? void (0) : __assert_fail
("!RepresentationType.isNull() && \"enum forward decl should be caught by Sema\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7105, __extension__ __PRETTY_FUNCTION__))
;
7106 const auto *AsBuiltin =
7107 RepresentationType.getCanonicalType()->castAs<BuiltinType>();
7108 // Recurse into the underlying type. Treat std::byte transparently as
7109 // unsigned char.
7110 return visit(AsBuiltin, Offset, /*EnumTy=*/Ty);
7111 }
7112
7113 Optional<APValue> visit(const ConstantArrayType *Ty, CharUnits Offset) {
7114 size_t Size = Ty->getSize().getLimitedValue();
7115 CharUnits ElementWidth = Info.Ctx.getTypeSizeInChars(Ty->getElementType());
7116
7117 APValue ArrayValue(APValue::UninitArray(), Size, Size);
7118 for (size_t I = 0; I != Size; ++I) {
7119 Optional<APValue> ElementValue =
7120 visitType(Ty->getElementType(), Offset + I * ElementWidth);
7121 if (!ElementValue)
7122 return None;
7123 ArrayValue.getArrayInitializedElt(I) = std::move(*ElementValue);
7124 }
7125
7126 return ArrayValue;
7127 }
7128
7129 Optional<APValue> visit(const Type *Ty, CharUnits Offset) {
7130 return unsupportedType(QualType(Ty, 0));
7131 }
7132
7133 Optional<APValue> visitType(QualType Ty, CharUnits Offset) {
7134 QualType Can = Ty.getCanonicalType();
7135
7136 switch (Can->getTypeClass()) {
7137#define TYPE(Class, Base) \
7138 case Type::Class: \
7139 return visit(cast<Class##Type>(Can.getTypePtr()), Offset);
7140#define ABSTRACT_TYPE(Class, Base)
7141#define NON_CANONICAL_TYPE(Class, Base) \
7142 case Type::Class: \
7143 llvm_unreachable("non-canonical type should be impossible!")::llvm::llvm_unreachable_internal("non-canonical type should be impossible!"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7143)
;
7144#define DEPENDENT_TYPE(Class, Base) \
7145 case Type::Class: \
7146 llvm_unreachable( \::llvm::llvm_unreachable_internal("dependent types aren't supported in the constant evaluator!"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7147)
7147 "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-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7147)
;
7148#define NON_CANONICAL_UNLESS_DEPENDENT(Class, Base)case Type::Class: ::llvm::llvm_unreachable_internal("either dependent or not canonical!"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7148);
\
7149 case Type::Class: \
7150 llvm_unreachable("either dependent or not canonical!")::llvm::llvm_unreachable_internal("either dependent or not canonical!"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7150)
;
7151#include "clang/AST/TypeNodes.inc"
7152 }
7153 llvm_unreachable("Unhandled Type::TypeClass")::llvm::llvm_unreachable_internal("Unhandled Type::TypeClass"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7153)
;
7154 }
7155
7156public:
7157 // Pull out a full value of type DstType.
7158 static Optional<APValue> convert(EvalInfo &Info, BitCastBuffer &Buffer,
7159 const CastExpr *BCE) {
7160 BufferToAPValueConverter Converter(Info, Buffer, BCE);
7161 return Converter.visitType(BCE->getType(), CharUnits::fromQuantity(0));
7162 }
7163};
7164
7165static bool checkBitCastConstexprEligibilityType(SourceLocation Loc,
7166 QualType Ty, EvalInfo *Info,
7167 const ASTContext &Ctx,
7168 bool CheckingDest) {
7169 Ty = Ty.getCanonicalType();
7170
7171 auto diag = [&](int Reason) {
7172 if (Info)
7173 Info->FFDiag(Loc, diag::note_constexpr_bit_cast_invalid_type)
7174 << CheckingDest << (Reason == 4) << Reason;
7175 return false;
7176 };
7177 auto note = [&](int Construct, QualType NoteTy, SourceLocation NoteLoc) {
7178 if (Info)
7179 Info->Note(NoteLoc, diag::note_constexpr_bit_cast_invalid_subtype)
7180 << NoteTy << Construct << Ty;
7181 return false;
7182 };
7183
7184 if (Ty->isUnionType())
7185 return diag(0);
7186 if (Ty->isPointerType())
7187 return diag(1);
7188 if (Ty->isMemberPointerType())
7189 return diag(2);
7190 if (Ty.isVolatileQualified())
7191 return diag(3);
7192
7193 if (RecordDecl *Record = Ty->getAsRecordDecl()) {
7194 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(Record)) {
7195 for (CXXBaseSpecifier &BS : CXXRD->bases())
7196 if (!checkBitCastConstexprEligibilityType(Loc, BS.getType(), Info, Ctx,
7197 CheckingDest))
7198 return note(1, BS.getType(), BS.getBeginLoc());
7199 }
7200 for (FieldDecl *FD : Record->fields()) {
7201 if (FD->getType()->isReferenceType())
7202 return diag(4);
7203 if (!checkBitCastConstexprEligibilityType(Loc, FD->getType(), Info, Ctx,
7204 CheckingDest))
7205 return note(0, FD->getType(), FD->getBeginLoc());
7206 }
7207 }
7208
7209 if (Ty->isArrayType() &&
7210 !checkBitCastConstexprEligibilityType(Loc, Ctx.getBaseElementType(Ty),
7211 Info, Ctx, CheckingDest))
7212 return false;
7213
7214 return true;
7215}
7216
7217static bool checkBitCastConstexprEligibility(EvalInfo *Info,
7218 const ASTContext &Ctx,
7219 const CastExpr *BCE) {
7220 bool DestOK = checkBitCastConstexprEligibilityType(
7221 BCE->getBeginLoc(), BCE->getType(), Info, Ctx, true);
7222 bool SourceOK = DestOK && checkBitCastConstexprEligibilityType(
7223 BCE->getBeginLoc(),
7224 BCE->getSubExpr()->getType(), Info, Ctx, false);
7225 return SourceOK;
7226}
7227
7228static bool handleLValueToRValueBitCast(EvalInfo &Info, APValue &DestValue,
7229 APValue &SourceValue,
7230 const CastExpr *BCE) {
7231 assert(CHAR_BIT == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 &&(static_cast <bool> (8 == 8 && Info.Ctx.getTargetInfo
().getCharWidth() == 8 && "no host or target supports non 8-bit chars"
) ? void (0) : __assert_fail ("CHAR_BIT == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 && \"no host or target supports non 8-bit chars\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7232, __extension__ __PRETTY_FUNCTION__))
7232 "no host or target supports non 8-bit chars")(static_cast <bool> (8 == 8 && Info.Ctx.getTargetInfo
().getCharWidth() == 8 && "no host or target supports non 8-bit chars"
) ? void (0) : __assert_fail ("CHAR_BIT == 8 && Info.Ctx.getTargetInfo().getCharWidth() == 8 && \"no host or target supports non 8-bit chars\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7232, __extension__ __PRETTY_FUNCTION__))
;
7233 assert(SourceValue.isLValue() &&(static_cast <bool> (SourceValue.isLValue() && "LValueToRValueBitcast requires an lvalue operand!"
) ? void (0) : __assert_fail ("SourceValue.isLValue() && \"LValueToRValueBitcast requires an lvalue operand!\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7234, __extension__ __PRETTY_FUNCTION__))
7234 "LValueToRValueBitcast requires an lvalue operand!")(static_cast <bool> (SourceValue.isLValue() && "LValueToRValueBitcast requires an lvalue operand!"
) ? void (0) : __assert_fail ("SourceValue.isLValue() && \"LValueToRValueBitcast requires an lvalue operand!\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7234, __extension__ __PRETTY_FUNCTION__))
;
7235
7236 if (!checkBitCastConstexprEligibility(&Info, Info.Ctx, BCE))
7237 return false;
7238
7239 LValue SourceLValue;
7240 APValue SourceRValue;
7241 SourceLValue.setFrom(Info.Ctx, SourceValue);
7242 if (!handleLValueToRValueConversion(
7243 Info, BCE, BCE->getSubExpr()->getType().withConst(), SourceLValue,
7244 SourceRValue, /*WantObjectRepresentation=*/true))
7245 return false;
7246
7247 // Read out SourceValue into a char buffer.
7248 Optional<BitCastBuffer> Buffer =
7249 APValueToBufferConverter::convert(Info, SourceRValue, BCE);
7250 if (!Buffer)
7251 return false;
7252
7253 // Write out the buffer into a new APValue.
7254 Optional<APValue> MaybeDestValue =
7255 BufferToAPValueConverter::convert(Info, *Buffer, BCE);
7256 if (!MaybeDestValue)
7257 return false;
7258
7259 DestValue = std::move(*MaybeDestValue);
7260 return true;
7261}
7262
7263template <class Derived>
7264class ExprEvaluatorBase
7265 : public ConstStmtVisitor<Derived, bool> {
7266private:
7267 Derived &getDerived() { return static_cast<Derived&>(*this); }
7268 bool DerivedSuccess(const APValue &V, const Expr *E) {
7269 return getDerived().Success(V, E);
7270 }
7271 bool DerivedZeroInitialization(const Expr *E) {
7272 return getDerived().ZeroInitialization(E);
7273 }
7274
7275 // Check whether a conditional operator with a non-constant condition is a
7276 // potential constant expression. If neither arm is a potential constant
7277 // expression, then the conditional operator is not either.
7278 template<typename ConditionalOperator>
7279 void CheckPotentialConstantConditional(const ConditionalOperator *E) {
7280 assert(Info.checkingPotentialConstantExpression())(static_cast <bool> (Info.checkingPotentialConstantExpression
()) ? void (0) : __assert_fail ("Info.checkingPotentialConstantExpression()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7280, __extension__ __PRETTY_FUNCTION__))
;
7281
7282 // Speculatively evaluate both arms.
7283 SmallVector<PartialDiagnosticAt, 8> Diag;
7284 {
7285 SpeculativeEvaluationRAII Speculate(Info, &Diag);
7286 StmtVisitorTy::Visit(E->getFalseExpr());
7287 if (Diag.empty())
7288 return;
7289 }
7290
7291 {
7292 SpeculativeEvaluationRAII Speculate(Info, &Diag);
7293 Diag.clear();
7294 StmtVisitorTy::Visit(E->getTrueExpr());
7295 if (Diag.empty())
7296 return;
7297 }
7298
7299 Error(E, diag::note_constexpr_conditional_never_const);
7300 }
7301
7302
7303 template<typename ConditionalOperator>
7304 bool HandleConditionalOperator(const ConditionalOperator *E) {
7305 bool BoolResult;
7306 if (!EvaluateAsBooleanCondition(E->getCond(), BoolResult, Info)) {
7307 if (Info.checkingPotentialConstantExpression() && Info.noteFailure()) {
7308 CheckPotentialConstantConditional(E);
7309 return false;
7310 }
7311 if (Info.noteFailure()) {
7312 StmtVisitorTy::Visit(E->getTrueExpr());
7313 StmtVisitorTy::Visit(E->getFalseExpr());
7314 }
7315 return false;
7316 }
7317
7318 Expr *EvalExpr = BoolResult ? E->getTrueExpr() : E->getFalseExpr();
7319 return StmtVisitorTy::Visit(EvalExpr);
7320 }
7321
7322protected:
7323 EvalInfo &Info;
7324 typedef ConstStmtVisitor<Derived, bool> StmtVisitorTy;
7325 typedef ExprEvaluatorBase ExprEvaluatorBaseTy;
7326
7327 OptionalDiagnostic CCEDiag(const Expr *E, diag::kind D) {
7328 return Info.CCEDiag(E, D);
7329 }
7330
7331 bool ZeroInitialization(const Expr *E) { return Error(E); }
7332
7333public:
7334 ExprEvaluatorBase(EvalInfo &Info) : Info(Info) {}
7335
7336 EvalInfo &getEvalInfo() { return Info; }
7337
7338 /// Report an evaluation error. This should only be called when an error is
7339 /// first discovered. When propagating an error, just return false.
7340 bool Error(const Expr *E, diag::kind D) {
7341 Info.FFDiag(E, D);
7342 return false;
7343 }
7344 bool Error(const Expr *E) {
7345 return Error(E, diag::note_invalid_subexpr_in_const_expr);
7346 }
7347
7348 bool VisitStmt(const Stmt *) {
7349 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-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7349)
;
7350 }
7351 bool VisitExpr(const Expr *E) {
7352 return Error(E);
7353 }
7354
7355 bool VisitConstantExpr(const ConstantExpr *E) {
7356 if (E->hasAPValueResult())
7357 return DerivedSuccess(E->getAPValueResult(), E);
7358
7359 return StmtVisitorTy::Visit(E->getSubExpr());
7360 }
7361
7362 bool VisitParenExpr(const ParenExpr *E)
7363 { return StmtVisitorTy::Visit(E->getSubExpr()); }
7364 bool VisitUnaryExtension(const UnaryOperator *E)
7365 { return StmtVisitorTy::Visit(E->getSubExpr()); }
7366 bool VisitUnaryPlus(const UnaryOperator *E)
7367 { return StmtVisitorTy::Visit(E->getSubExpr()); }
7368 bool VisitChooseExpr(const ChooseExpr *E)
7369 { return StmtVisitorTy::Visit(E->getChosenSubExpr()); }
7370 bool VisitGenericSelectionExpr(const GenericSelectionExpr *E)
7371 { return StmtVisitorTy::Visit(E->getResultExpr()); }
7372 bool VisitSubstNonTypeTemplateParmExpr(const SubstNonTypeTemplateParmExpr *E)
7373 { return StmtVisitorTy::Visit(E->getReplacement()); }
7374 bool VisitCXXDefaultArgExpr(const CXXDefaultArgExpr *E) {
7375 TempVersionRAII RAII(*Info.CurrentCall);
7376 SourceLocExprScopeGuard Guard(E, Info.CurrentCall->CurSourceLocExprScope);
7377 return StmtVisitorTy::Visit(E->getExpr());
7378 }
7379 bool VisitCXXDefaultInitExpr(const CXXDefaultInitExpr *E) {
7380 TempVersionRAII RAII(*Info.CurrentCall);
7381 // The initializer may not have been parsed yet, or might be erroneous.
7382 if (!E->getExpr())
7383 return Error(E);
7384 SourceLocExprScopeGuard Guard(E, Info.CurrentCall->CurSourceLocExprScope);
7385 return StmtVisitorTy::Visit(E->getExpr());
7386 }
7387
7388 bool VisitExprWithCleanups(const ExprWithCleanups *E) {
7389 FullExpressionRAII Scope(Info);
7390 return StmtVisitorTy::Visit(E->getSubExpr()) && Scope.destroy();
7391 }
7392
7393 // Temporaries are registered when created, so we don't care about
7394 // CXXBindTemporaryExpr.
7395 bool VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *E) {
7396 return StmtVisitorTy::Visit(E->getSubExpr());
7397 }
7398
7399 bool VisitCXXReinterpretCastExpr(const CXXReinterpretCastExpr *E) {
7400 CCEDiag(E, diag::note_constexpr_invalid_cast) << 0;
7401 return static_cast<Derived*>(this)->VisitCastExpr(E);
7402 }
7403 bool VisitCXXDynamicCastExpr(const CXXDynamicCastExpr *E) {
7404 if (!Info.Ctx.getLangOpts().CPlusPlus20)
7405 CCEDiag(E, diag::note_constexpr_invalid_cast) << 1;
7406 return static_cast<Derived*>(this)->VisitCastExpr(E);
7407 }
7408 bool VisitBuiltinBitCastExpr(const BuiltinBitCastExpr *E) {
7409 return static_cast<Derived*>(this)->VisitCastExpr(E);
7410 }
7411
7412 bool VisitBinaryOperator(const BinaryOperator *E) {
7413 switch (E->getOpcode()) {
7414 default:
7415 return Error(E);
7416
7417 case BO_Comma:
7418 VisitIgnoredValue(E->getLHS());
7419 return StmtVisitorTy::Visit(E->getRHS());
7420
7421 case BO_PtrMemD:
7422 case BO_PtrMemI: {
7423 LValue Obj;
7424 if (!HandleMemberPointerAccess(Info, E, Obj))
7425 return false;
7426 APValue Result;
7427 if (!handleLValueToRValueConversion(Info, E, E->getType(), Obj, Result))
7428 return false;
7429 return DerivedSuccess(Result, E);
7430 }
7431 }
7432 }
7433
7434 bool VisitCXXRewrittenBinaryOperator(const CXXRewrittenBinaryOperator *E) {
7435 return StmtVisitorTy::Visit(E->getSemanticForm());
7436 }
7437
7438 bool VisitBinaryConditionalOperator(const BinaryConditionalOperator *E) {
7439 // Evaluate and cache the common expression. We treat it as a temporary,
7440 // even though it's not quite the same thing.
7441 LValue CommonLV;
7442 if (!Evaluate(Info.CurrentCall->createTemporary(
7443 E->getOpaqueValue(),
7444 getStorageType(Info.Ctx, E->getOpaqueValue()),
7445 ScopeKind::FullExpression, CommonLV),
7446 Info, E->getCommon()))
7447 return false;
7448
7449 return HandleConditionalOperator(E);
7450 }
7451
7452 bool VisitConditionalOperator(const ConditionalOperator *E) {
7453 bool IsBcpCall = false;
7454 // If the condition (ignoring parens) is a __builtin_constant_p call,
7455 // the result is a constant expression if it can be folded without
7456 // side-effects. This is an important GNU extension. See GCC PR38377
7457 // for discussion.
7458 if (const CallExpr *CallCE =
7459 dyn_cast<CallExpr>(E->getCond()->IgnoreParenCasts()))
7460 if (CallCE->getBuiltinCallee() == Builtin::BI__builtin_constant_p)
7461 IsBcpCall = true;
7462
7463 // Always assume __builtin_constant_p(...) ? ... : ... is a potential
7464 // constant expression; we can't check whether it's potentially foldable.
7465 // FIXME: We should instead treat __builtin_constant_p as non-constant if
7466 // it would return 'false' in this mode.
7467 if (Info.checkingPotentialConstantExpression() && IsBcpCall)
7468 return false;
7469
7470 FoldConstant Fold(Info, IsBcpCall);
7471 if (!HandleConditionalOperator(E)) {
7472 Fold.keepDiagnostics();
7473 return false;
7474 }
7475
7476 return true;
7477 }
7478
7479 bool VisitOpaqueValueExpr(const OpaqueValueExpr *E) {
7480 if (APValue *Value = Info.CurrentCall->getCurrentTemporary(E))
7481 return DerivedSuccess(*Value, E);
7482
7483 const Expr *Source = E->getSourceExpr();
7484 if (!Source)
7485 return Error(E);
7486 if (Source == E) { // sanity checking.
7487 assert(0 && "OpaqueValueExpr recursively refers to itself")(static_cast <bool> (0 && "OpaqueValueExpr recursively refers to itself"
) ? void (0) : __assert_fail ("0 && \"OpaqueValueExpr recursively refers to itself\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7487, __extension__ __PRETTY_FUNCTION__))
;
7488 return Error(E);
7489 }
7490 return StmtVisitorTy::Visit(Source);
7491 }
7492
7493 bool VisitPseudoObjectExpr(const PseudoObjectExpr *E) {
7494 for (const Expr *SemE : E->semantics()) {
7495 if (auto *OVE = dyn_cast<OpaqueValueExpr>(SemE)) {
7496 // FIXME: We can't handle the case where an OpaqueValueExpr is also the
7497 // result expression: there could be two different LValues that would
7498 // refer to the same object in that case, and we can't model that.
7499 if (SemE == E->getResultExpr())
7500 return Error(E);
7501
7502 // Unique OVEs get evaluated if and when we encounter them when
7503 // emitting the rest of the semantic form, rather than eagerly.
7504 if (OVE->isUnique())
7505 continue;
7506
7507 LValue LV;
7508 if (!Evaluate(Info.CurrentCall->createTemporary(
7509 OVE, getStorageType(Info.Ctx, OVE),
7510 ScopeKind::FullExpression, LV),
7511 Info, OVE->getSourceExpr()))
7512 return false;
7513 } else if (SemE == E->getResultExpr()) {
7514 if (!StmtVisitorTy::Visit(SemE))
7515 return false;
7516 } else {
7517 if (!EvaluateIgnoredValue(Info, SemE))
7518 return false;
7519 }
7520 }
7521 return true;
7522 }
7523
7524 bool VisitCallExpr(const CallExpr *E) {
7525 APValue Result;
7526 if (!handleCallExpr(E, Result, nullptr))
7527 return false;
7528 return DerivedSuccess(Result, E);
7529 }
7530
7531 bool handleCallExpr(const CallExpr *E, APValue &Result,
7532 const LValue *ResultSlot) {
7533 CallScopeRAII CallScope(Info);
7534
7535 const Expr *Callee = E->getCallee()->IgnoreParens();
7536 QualType CalleeType = Callee->getType();
7537
7538 const FunctionDecl *FD = nullptr;
7539 LValue *This = nullptr, ThisVal;
7540 auto Args = llvm::makeArrayRef(E->getArgs(), E->getNumArgs());
7541 bool HasQualifier = false;
7542
7543 CallRef Call;
7544
7545 // Extract function decl and 'this' pointer from the callee.
7546 if (CalleeType->isSpecificBuiltinType(BuiltinType::BoundMember)) {
7547 const CXXMethodDecl *Member = nullptr;
7548 if (const MemberExpr *ME = dyn_cast<MemberExpr>(Callee)) {
7549 // Explicit bound member calls, such as x.f() or p->g();
7550 if (!EvaluateObjectArgument(Info, ME->getBase(), ThisVal))
7551 return false;
7552 Member = dyn_cast<CXXMethodDecl>(ME->getMemberDecl());
7553 if (!Member)
7554 return Error(Callee);
7555 This = &ThisVal;
7556 HasQualifier = ME->hasQualifier();
7557 } else if (const BinaryOperator *BE = dyn_cast<BinaryOperator>(Callee)) {
7558 // Indirect bound member calls ('.*' or '->*').
7559 const ValueDecl *D =
7560 HandleMemberPointerAccess(Info, BE, ThisVal, false);
7561 if (!D)
7562 return false;
7563 Member = dyn_cast<CXXMethodDecl>(D);
7564 if (!Member)
7565 return Error(Callee);
7566 This = &ThisVal;
7567 } else if (const auto *PDE = dyn_cast<CXXPseudoDestructorExpr>(Callee)) {
7568 if (!Info.getLangOpts().CPlusPlus20)
7569 Info.CCEDiag(PDE, diag::note_constexpr_pseudo_destructor);
7570 return EvaluateObjectArgument(Info, PDE->getBase(), ThisVal) &&
7571 HandleDestruction(Info, PDE, ThisVal, PDE->getDestroyedType());
7572 } else
7573 return Error(Callee);
7574 FD = Member;
7575 } else if (CalleeType->isFunctionPointerType()) {
7576 LValue CalleeLV;
7577 if (!EvaluatePointer(Callee, CalleeLV, Info))
7578 return false;
7579
7580 if (!CalleeLV.getLValueOffset().isZero())
7581 return Error(Callee);
7582 FD = dyn_cast_or_null<FunctionDecl>(
7583 CalleeLV.getLValueBase().dyn_cast<const ValueDecl *>());
7584 if (!FD)
7585 return Error(Callee);
7586 // Don't call function pointers which have been cast to some other type.
7587 // Per DR (no number yet), the caller and callee can differ in noexcept.
7588 if (!Info.Ctx.hasSameFunctionTypeIgnoringExceptionSpec(
7589 CalleeType->getPointeeType(), FD->getType())) {
7590 return Error(E);
7591 }
7592
7593 // For an (overloaded) assignment expression, evaluate the RHS before the
7594 // LHS.
7595 auto *OCE = dyn_cast<CXXOperatorCallExpr>(E);
7596 if (OCE && OCE->isAssignmentOp()) {
7597 assert(Args.size() == 2 && "wrong number of arguments in assignment")(static_cast <bool> (Args.size() == 2 && "wrong number of arguments in assignment"
) ? void (0) : __assert_fail ("Args.size() == 2 && \"wrong number of arguments in assignment\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7597, __extension__ __PRETTY_FUNCTION__))
;
7598 Call = Info.CurrentCall->createCall(FD);
7599 if (!EvaluateArgs(isa<CXXMethodDecl>(FD) ? Args.slice(1) : Args, Call,
7600 Info, FD, /*RightToLeft=*/true))
7601 return false;
7602 }
7603
7604 // Overloaded operator calls to member functions are represented as normal
7605 // calls with '*this' as the first argument.
7606 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
7607 if (MD && !MD->isStatic()) {
7608 // FIXME: When selecting an implicit conversion for an overloaded
7609 // operator delete, we sometimes try to evaluate calls to conversion
7610 // operators without a 'this' parameter!
7611 if (Args.empty())
7612 return Error(E);
7613
7614 if (!EvaluateObjectArgument(Info, Args[0], ThisVal))
7615 return false;
7616 This = &ThisVal;
7617 Args = Args.slice(1);
7618 } else if (MD && MD->isLambdaStaticInvoker()) {
7619 // Map the static invoker for the lambda back to the call operator.
7620 // Conveniently, we don't have to slice out the 'this' argument (as is
7621 // being done for the non-static case), since a static member function
7622 // doesn't have an implicit argument passed in.
7623 const CXXRecordDecl *ClosureClass = MD->getParent();
7624 assert((static_cast <bool> (ClosureClass->captures_begin() ==
ClosureClass->captures_end() && "Number of captures must be zero for conversion to function-ptr"
) ? void (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7626, __extension__ __PRETTY_FUNCTION__))
7625 ClosureClass->captures_begin() == ClosureClass->captures_end() &&(static_cast <bool> (ClosureClass->captures_begin() ==
ClosureClass->captures_end() && "Number of captures must be zero for conversion to function-ptr"
) ? void (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7626, __extension__ __PRETTY_FUNCTION__))
7626 "Number of captures must be zero for conversion to function-ptr")(static_cast <bool> (ClosureClass->captures_begin() ==
ClosureClass->captures_end() && "Number of captures must be zero for conversion to function-ptr"
) ? void (0) : __assert_fail ("ClosureClass->captures_begin() == ClosureClass->captures_end() && \"Number of captures must be zero for conversion to function-ptr\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7626, __extension__ __PRETTY_FUNCTION__))
;
7627
7628 const CXXMethodDecl *LambdaCallOp =
7629 ClosureClass->getLambdaCallOperator();
7630
7631 // Set 'FD', the function that will be called below, to the call
7632 // operator. If the closure object represents a generic lambda, find
7633 // the corresponding specialization of the call operator.
7634
7635 if (ClosureClass->isGenericLambda()) {
7636 assert(MD->isFunctionTemplateSpecialization() &&(static_cast <bool> (MD->isFunctionTemplateSpecialization
() && "A generic lambda's static-invoker function must be a "
"template specialization") ? void (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7638, __extension__ __PRETTY_FUNCTION__))
7637 "A generic lambda's static-invoker function must be a "(static_cast <bool> (MD->isFunctionTemplateSpecialization
() && "A generic lambda's static-invoker function must be a "
"template specialization") ? void (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7638, __extension__ __PRETTY_FUNCTION__))
7638 "template specialization")(static_cast <bool> (MD->isFunctionTemplateSpecialization
() && "A generic lambda's static-invoker function must be a "
"template specialization") ? void (0) : __assert_fail ("MD->isFunctionTemplateSpecialization() && \"A generic lambda's static-invoker function must be a \" \"template specialization\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7638, __extension__ __PRETTY_FUNCTION__))
;
7639 const TemplateArgumentList *TAL = MD->getTemplateSpecializationArgs();
7640 FunctionTemplateDecl *CallOpTemplate =
7641 LambdaCallOp->getDescribedFunctionTemplate();
7642 void *InsertPos = nullptr;
7643 FunctionDecl *CorrespondingCallOpSpecialization =
7644 CallOpTemplate->findSpecialization(TAL->asArray(), InsertPos);
7645 assert(CorrespondingCallOpSpecialization &&(static_cast <bool> (CorrespondingCallOpSpecialization &&
"We must always have a function call operator specialization "
"that corresponds to our static invoker specialization") ? void
(0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7647, __extension__ __PRETTY_FUNCTION__))
7646 "We must always have a function call operator specialization "(static_cast <bool> (CorrespondingCallOpSpecialization &&
"We must always have a function call operator specialization "
"that corresponds to our static invoker specialization") ? void
(0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7647, __extension__ __PRETTY_FUNCTION__))
7647 "that corresponds to our static invoker specialization")(static_cast <bool> (CorrespondingCallOpSpecialization &&
"We must always have a function call operator specialization "
"that corresponds to our static invoker specialization") ? void
(0) : __assert_fail ("CorrespondingCallOpSpecialization && \"We must always have a function call operator specialization \" \"that corresponds to our static invoker specialization\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7647, __extension__ __PRETTY_FUNCTION__))
;
7648 FD = cast<CXXMethodDecl>(CorrespondingCallOpSpecialization);
7649 } else
7650 FD = LambdaCallOp;
7651 } else if (FD->isReplaceableGlobalAllocationFunction()) {
7652 if (FD->getDeclName().getCXXOverloadedOperator() == OO_New ||
7653 FD->getDeclName().getCXXOverloadedOperator() == OO_Array_New) {
7654 LValue Ptr;
7655 if (!HandleOperatorNewCall(Info, E, Ptr))
7656 return false;
7657 Ptr.moveInto(Result);
7658 return CallScope.destroy();
7659 } else {
7660 return HandleOperatorDeleteCall(Info, E) && CallScope.destroy();
7661 }
7662 }
7663 } else
7664 return Error(E);
7665
7666 // Evaluate the arguments now if we've not already done so.
7667 if (!Call) {
7668 Call = Info.CurrentCall->createCall(FD);
7669 if (!EvaluateArgs(Args, Call, Info, FD))
7670 return false;
7671 }
7672
7673 SmallVector<QualType, 4> CovariantAdjustmentPath;
7674 if (This) {
7675 auto *NamedMember = dyn_cast<CXXMethodDecl>(FD);
7676 if (NamedMember && NamedMember->isVirtual() && !HasQualifier) {
7677 // Perform virtual dispatch, if necessary.
7678 FD = HandleVirtualDispatch(Info, E, *This, NamedMember,
7679 CovariantAdjustmentPath);
7680 if (!FD)
7681 return false;
7682 } else {
7683 // Check that the 'this' pointer points to an object of the right type.
7684 // FIXME: If this is an assignment operator call, we may need to change
7685 // the active union member before we check this.
7686 if (!checkNonVirtualMemberCallThisPointer(Info, E, *This, NamedMember))
7687 return false;
7688 }
7689 }
7690
7691 // Destructor calls are different enough that they have their own codepath.
7692 if (auto *DD = dyn_cast<CXXDestructorDecl>(FD)) {
7693 assert(This && "no 'this' pointer for destructor call")(static_cast <bool> (This && "no 'this' pointer for destructor call"
) ? void (0) : __assert_fail ("This && \"no 'this' pointer for destructor call\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7693, __extension__ __PRETTY_FUNCTION__))
;
7694 return HandleDestruction(Info, E, *This,
7695 Info.Ctx.getRecordType(DD->getParent())) &&
7696 CallScope.destroy();
7697 }
7698
7699 const FunctionDecl *Definition = nullptr;
7700 Stmt *Body = FD->getBody(Definition);
7701
7702 if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body) ||
7703 !HandleFunctionCall(E->getExprLoc(), Definition, This, Args, Call,
7704 Body, Info, Result, ResultSlot))
7705 return false;
7706
7707 if (!CovariantAdjustmentPath.empty() &&
7708 !HandleCovariantReturnAdjustment(Info, E, Result,
7709 CovariantAdjustmentPath))
7710 return false;
7711
7712 return CallScope.destroy();
7713 }
7714
7715 bool VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) {
7716 return StmtVisitorTy::Visit(E->getInitializer());
7717 }
7718 bool VisitInitListExpr(const InitListExpr *E) {
7719 if (E->getNumInits() == 0)
7720 return DerivedZeroInitialization(E);
7721 if (E->getNumInits() == 1)
7722 return StmtVisitorTy::Visit(E->getInit(0));
7723 return Error(E);
7724 }
7725 bool VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
7726 return DerivedZeroInitialization(E);
7727 }
7728 bool VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) {
7729 return DerivedZeroInitialization(E);
7730 }
7731 bool VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) {
7732 return DerivedZeroInitialization(E);
7733 }
7734
7735 /// A member expression where the object is a prvalue is itself a prvalue.
7736 bool VisitMemberExpr(const MemberExpr *E) {
7737 assert(!Info.Ctx.getLangOpts().CPlusPlus11 &&(static_cast <bool> (!Info.Ctx.getLangOpts().CPlusPlus11
&& "missing temporary materialization conversion") ?
void (0) : __assert_fail ("!Info.Ctx.getLangOpts().CPlusPlus11 && \"missing temporary materialization conversion\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7738, __extension__ __PRETTY_FUNCTION__))
7738 "missing temporary materialization conversion")(static_cast <bool> (!Info.Ctx.getLangOpts().CPlusPlus11
&& "missing temporary materialization conversion") ?
void (0) : __assert_fail ("!Info.Ctx.getLangOpts().CPlusPlus11 && \"missing temporary materialization conversion\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7738, __extension__ __PRETTY_FUNCTION__))
;
7739 assert(!E->isArrow() && "missing call to bound member function?")(static_cast <bool> (!E->isArrow() && "missing call to bound member function?"
) ? void (0) : __assert_fail ("!E->isArrow() && \"missing call to bound member function?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7739, __extension__ __PRETTY_FUNCTION__))
;
7740
7741 APValue Val;
7742 if (!Evaluate(Val, Info, E->getBase()))
7743 return false;
7744
7745 QualType BaseTy = E->getBase()->getType();
7746
7747 const FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl());
7748 if (!FD) return Error(E);
7749 assert(!FD->getType()->isReferenceType() && "prvalue reference?")(static_cast <bool> (!FD->getType()->isReferenceType
() && "prvalue reference?") ? void (0) : __assert_fail
("!FD->getType()->isReferenceType() && \"prvalue reference?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7749, __extension__ __PRETTY_FUNCTION__))
;
7750 assert(BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() ==(static_cast <bool> (BaseTy->castAs<RecordType>
()->getDecl()->getCanonicalDecl() == FD->getParent()
->getCanonicalDecl() && "record / field mismatch")
? void (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7751, __extension__ __PRETTY_FUNCTION__))
7751 FD->getParent()->getCanonicalDecl() && "record / field mismatch")(static_cast <bool> (BaseTy->castAs<RecordType>
()->getDecl()->getCanonicalDecl() == FD->getParent()
->getCanonicalDecl() && "record / field mismatch")
? void (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7751, __extension__ __PRETTY_FUNCTION__))
;
7752
7753 // Note: there is no lvalue base here. But this case should only ever
7754 // happen in C or in C++98, where we cannot be evaluating a constexpr
7755 // constructor, which is the only case the base matters.
7756 CompleteObject Obj(APValue::LValueBase(), &Val, BaseTy);
7757 SubobjectDesignator Designator(BaseTy);
7758 Designator.addDeclUnchecked(FD);
7759
7760 APValue Result;
7761 return extractSubobject(Info, E, Obj, Designator, Result) &&
7762 DerivedSuccess(Result, E);
7763 }
7764
7765 bool VisitExtVectorElementExpr(const ExtVectorElementExpr *E) {
7766 APValue Val;
7767 if (!Evaluate(Val, Info, E->getBase()))
7768 return false;
7769
7770 if (Val.isVector()) {
7771 SmallVector<uint32_t, 4> Indices;
7772 E->getEncodedElementAccess(Indices);
7773 if (Indices.size() == 1) {
7774 // Return scalar.
7775 return DerivedSuccess(Val.getVectorElt(Indices[0]), E);
7776 } else {
7777 // Construct new APValue vector.
7778 SmallVector<APValue, 4> Elts;
7779 for (unsigned I = 0; I < Indices.size(); ++I) {
7780 Elts.push_back(Val.getVectorElt(Indices[I]));
7781 }
7782 APValue VecResult(Elts.data(), Indices.size());
7783 return DerivedSuccess(VecResult, E);
7784 }
7785 }
7786
7787 return false;
7788 }
7789
7790 bool VisitCastExpr(const CastExpr *E) {
7791 switch (E->getCastKind()) {
7792 default:
7793 break;
7794
7795 case CK_AtomicToNonAtomic: {
7796 APValue AtomicVal;
7797 // This does not need to be done in place even for class/array types:
7798 // atomic-to-non-atomic conversion implies copying the object
7799 // representation.
7800 if (!Evaluate(AtomicVal, Info, E->getSubExpr()))
7801 return false;
7802 return DerivedSuccess(AtomicVal, E);
7803 }
7804
7805 case CK_NoOp:
7806 case CK_UserDefinedConversion:
7807 return StmtVisitorTy::Visit(E->getSubExpr());
7808
7809 case CK_LValueToRValue: {
7810 LValue LVal;
7811 if (!EvaluateLValue(E->getSubExpr(), LVal, Info))
7812 return false;
7813 APValue RVal;
7814 // Note, we use the subexpression's type in order to retain cv-qualifiers.
7815 if (!handleLValueToRValueConversion(Info, E, E->getSubExpr()->getType(),
7816 LVal, RVal))
7817 return false;
7818 return DerivedSuccess(RVal, E);
7819 }
7820 case CK_LValueToRValueBitCast: {
7821 APValue DestValue, SourceValue;
7822 if (!Evaluate(SourceValue, Info, E->getSubExpr()))
7823 return false;
7824 if (!handleLValueToRValueBitCast(Info, DestValue, SourceValue, E))
7825 return false;
7826 return DerivedSuccess(DestValue, E);
7827 }
7828
7829 case CK_AddressSpaceConversion: {
7830 APValue Value;
7831 if (!Evaluate(Value, Info, E->getSubExpr()))
7832 return false;
7833 return DerivedSuccess(Value, E);
7834 }
7835 }
7836
7837 return Error(E);
7838 }
7839
7840 bool VisitUnaryPostInc(const UnaryOperator *UO) {
7841 return VisitUnaryPostIncDec(UO);
7842 }
7843 bool VisitUnaryPostDec(const UnaryOperator *UO) {
7844 return VisitUnaryPostIncDec(UO);
7845 }
7846 bool VisitUnaryPostIncDec(const UnaryOperator *UO) {
7847 if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
7848 return Error(UO);
7849
7850 LValue LVal;
7851 if (!EvaluateLValue(UO->getSubExpr(), LVal, Info))
7852 return false;
7853 APValue RVal;
7854 if (!handleIncDec(this->Info, UO, LVal, UO->getSubExpr()->getType(),
7855 UO->isIncrementOp(), &RVal))
7856 return false;
7857 return DerivedSuccess(RVal, UO);
7858 }
7859
7860 bool VisitStmtExpr(const StmtExpr *E) {
7861 // We will have checked the full-expressions inside the statement expression
7862 // when they were completed, and don't need to check them again now.
7863 llvm::SaveAndRestore<bool> NotCheckingForUB(
7864 Info.CheckingForUndefinedBehavior, false);
7865
7866 const CompoundStmt *CS = E->getSubStmt();
7867 if (CS->body_empty())
7868 return true;
7869
7870 BlockScopeRAII Scope(Info);
7871 for (CompoundStmt::const_body_iterator BI = CS->body_begin(),
7872 BE = CS->body_end();
7873 /**/; ++BI) {
7874 if (BI + 1 == BE) {
7875 const Expr *FinalExpr = dyn_cast<Expr>(*BI);
7876 if (!FinalExpr) {
7877 Info.FFDiag((*BI)->getBeginLoc(),
7878 diag::note_constexpr_stmt_expr_unsupported);
7879 return false;
7880 }
7881 return this->Visit(FinalExpr) && Scope.destroy();
7882 }
7883
7884 APValue ReturnValue;
7885 StmtResult Result = { ReturnValue, nullptr };
7886 EvalStmtResult ESR = EvaluateStmt(Result, Info, *BI);
7887 if (ESR != ESR_Succeeded) {
7888 // FIXME: If the statement-expression terminated due to 'return',
7889 // 'break', or 'continue', it would be nice to propagate that to
7890 // the outer statement evaluation rather than bailing out.
7891 if (ESR != ESR_Failed)
7892 Info.FFDiag((*BI)->getBeginLoc(),
7893 diag::note_constexpr_stmt_expr_unsupported);
7894 return false;
7895 }
7896 }
7897
7898 llvm_unreachable("Return from function from the loop above.")::llvm::llvm_unreachable_internal("Return from function from the loop above."
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7898)
;
7899 }
7900
7901 /// Visit a value which is evaluated, but whose value is ignored.
7902 void VisitIgnoredValue(const Expr *E) {
7903 EvaluateIgnoredValue(Info, E);
7904 }
7905
7906 /// Potentially visit a MemberExpr's base expression.
7907 void VisitIgnoredBaseExpression(const Expr *E) {
7908 // While MSVC doesn't evaluate the base expression, it does diagnose the
7909 // presence of side-effecting behavior.
7910 if (Info.getLangOpts().MSVCCompat && !E->HasSideEffects(Info.Ctx))
7911 return;
7912 VisitIgnoredValue(E);
7913 }
7914};
7915
7916} // namespace
7917
7918//===----------------------------------------------------------------------===//
7919// Common base class for lvalue and temporary evaluation.
7920//===----------------------------------------------------------------------===//
7921namespace {
7922template<class Derived>
7923class LValueExprEvaluatorBase
7924 : public ExprEvaluatorBase<Derived> {
7925protected:
7926 LValue &Result;
7927 bool InvalidBaseOK;
7928 typedef LValueExprEvaluatorBase LValueExprEvaluatorBaseTy;
7929 typedef ExprEvaluatorBase<Derived> ExprEvaluatorBaseTy;
7930
7931 bool Success(APValue::LValueBase B) {
7932 Result.set(B);
7933 return true;
7934 }
7935
7936 bool evaluatePointer(const Expr *E, LValue &Result) {
7937 return EvaluatePointer(E, Result, this->Info, InvalidBaseOK);
7938 }
7939
7940public:
7941 LValueExprEvaluatorBase(EvalInfo &Info, LValue &Result, bool InvalidBaseOK)
7942 : ExprEvaluatorBaseTy(Info), Result(Result),
7943 InvalidBaseOK(InvalidBaseOK) {}
7944
7945 bool Success(const APValue &V, const Expr *E) {
7946 Result.setFrom(this->Info.Ctx, V);
7947 return true;
7948 }
7949
7950 bool VisitMemberExpr(const MemberExpr *E) {
7951 // Handle non-static data members.
7952 QualType BaseTy;
7953 bool EvalOK;
7954 if (E->isArrow()) {
7955 EvalOK = evaluatePointer(E->getBase(), Result);
7956 BaseTy = E->getBase()->getType()->castAs<PointerType>()->getPointeeType();
7957 } else if (E->getBase()->isPRValue()) {
7958 assert(E->getBase()->getType()->isRecordType())(static_cast <bool> (E->getBase()->getType()->
isRecordType()) ? void (0) : __assert_fail ("E->getBase()->getType()->isRecordType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7958, __extension__ __PRETTY_FUNCTION__))
;
7959 EvalOK = EvaluateTemporary(E->getBase(), Result, this->Info);
7960 BaseTy = E->getBase()->getType();
7961 } else {
7962 EvalOK = this->Visit(E->getBase());
7963 BaseTy = E->getBase()->getType();
7964 }
7965 if (!EvalOK) {
7966 if (!InvalidBaseOK)
7967 return false;
7968 Result.setInvalid(E);
7969 return true;
7970 }
7971
7972 const ValueDecl *MD = E->getMemberDecl();
7973 if (const FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl())) {
7974 assert(BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() ==(static_cast <bool> (BaseTy->castAs<RecordType>
()->getDecl()->getCanonicalDecl() == FD->getParent()
->getCanonicalDecl() && "record / field mismatch")
? void (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7975, __extension__ __PRETTY_FUNCTION__))
7975 FD->getParent()->getCanonicalDecl() && "record / field mismatch")(static_cast <bool> (BaseTy->castAs<RecordType>
()->getDecl()->getCanonicalDecl() == FD->getParent()
->getCanonicalDecl() && "record / field mismatch")
? void (0) : __assert_fail ("BaseTy->castAs<RecordType>()->getDecl()->getCanonicalDecl() == FD->getParent()->getCanonicalDecl() && \"record / field mismatch\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 7975, __extension__ __PRETTY_FUNCTION__))
;
7976 (void)BaseTy;
7977 if (!HandleLValueMember(this->Info, E, Result, FD))
7978 return false;
7979 } else if (const IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(MD)) {
7980 if (!HandleLValueIndirectMember(this->Info, E, Result, IFD))
7981 return false;
7982 } else
7983 return this->Error(E);
7984
7985 if (MD->getType()->isReferenceType()) {
7986 APValue RefValue;
7987 if (!handleLValueToRValueConversion(this->Info, E, MD->getType(), Result,
7988 RefValue))
7989 return false;
7990 return Success(RefValue, E);
7991 }
7992 return true;
7993 }
7994
7995 bool VisitBinaryOperator(const BinaryOperator *E) {
7996 switch (E->getOpcode()) {
7997 default:
7998 return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
7999
8000 case BO_PtrMemD:
8001 case BO_PtrMemI:
8002 return HandleMemberPointerAccess(this->Info, E, Result);
8003 }
8004 }
8005
8006 bool VisitCastExpr(const CastExpr *E) {
8007 switch (E->getCastKind()) {
8008 default:
8009 return ExprEvaluatorBaseTy::VisitCastExpr(E);
8010
8011 case CK_DerivedToBase:
8012 case CK_UncheckedDerivedToBase:
8013 if (!this->Visit(E->getSubExpr()))
8014 return false;
8015
8016 // Now figure out the necessary offset to add to the base LV to get from
8017 // the derived class to the base class.
8018 return HandleLValueBasePath(this->Info, E, E->getSubExpr()->getType(),
8019 Result);
8020 }
8021 }
8022};
8023}
8024
8025//===----------------------------------------------------------------------===//
8026// LValue Evaluation
8027//
8028// This is used for evaluating lvalues (in C and C++), xvalues (in C++11),
8029// function designators (in C), decl references to void objects (in C), and
8030// temporaries (if building with -Wno-address-of-temporary).
8031//
8032// LValue evaluation produces values comprising a base expression of one of the
8033// following types:
8034// - Declarations
8035// * VarDecl
8036// * FunctionDecl
8037// - Literals
8038// * CompoundLiteralExpr in C (and in global scope in C++)
8039// * StringLiteral
8040// * PredefinedExpr
8041// * ObjCStringLiteralExpr
8042// * ObjCEncodeExpr
8043// * AddrLabelExpr
8044// * BlockExpr
8045// * CallExpr for a MakeStringConstant builtin
8046// - typeid(T) expressions, as TypeInfoLValues
8047// - Locals and temporaries
8048// * MaterializeTemporaryExpr
8049// * Any Expr, with a CallIndex indicating the function in which the temporary
8050// was evaluated, for cases where the MaterializeTemporaryExpr is missing
8051// from the AST (FIXME).
8052// * A MaterializeTemporaryExpr that has static storage duration, with no
8053// CallIndex, for a lifetime-extended temporary.
8054// * The ConstantExpr that is currently being evaluated during evaluation of an
8055// immediate invocation.
8056// plus an offset in bytes.
8057//===----------------------------------------------------------------------===//
8058namespace {
8059class LValueExprEvaluator
8060 : public LValueExprEvaluatorBase<LValueExprEvaluator> {
8061public:
8062 LValueExprEvaluator(EvalInfo &Info, LValue &Result, bool InvalidBaseOK) :
8063 LValueExprEvaluatorBaseTy(Info, Result, InvalidBaseOK) {}
8064
8065 bool VisitVarDecl(const Expr *E, const VarDecl *VD);
8066 bool VisitUnaryPreIncDec(const UnaryOperator *UO);
8067
8068 bool VisitDeclRefExpr(const DeclRefExpr *E);
8069 bool VisitPredefinedExpr(const PredefinedExpr *E) { return Success(E); }
8070 bool VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E);
8071 bool VisitCompoundLiteralExpr(const CompoundLiteralExpr *E);
8072 bool VisitMemberExpr(const MemberExpr *E);
8073 bool VisitStringLiteral(const StringLiteral *E) { return Success(E); }
8074 bool VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { return Success(E); }
8075 bool VisitCXXTypeidExpr(const CXXTypeidExpr *E);
8076 bool VisitCXXUuidofExpr(const CXXUuidofExpr *E);
8077 bool VisitArraySubscriptExpr(const ArraySubscriptExpr *E);
8078 bool VisitUnaryDeref(const UnaryOperator *E);
8079 bool VisitUnaryReal(const UnaryOperator *E);
8080 bool VisitUnaryImag(const UnaryOperator *E);
8081 bool VisitUnaryPreInc(const UnaryOperator *UO) {
8082 return VisitUnaryPreIncDec(UO);
8083 }
8084 bool VisitUnaryPreDec(const UnaryOperator *UO) {
8085 return VisitUnaryPreIncDec(UO);
8086 }
8087 bool VisitBinAssign(const BinaryOperator *BO);
8088 bool VisitCompoundAssignOperator(const CompoundAssignOperator *CAO);
8089
8090 bool VisitCastExpr(const CastExpr *E) {
8091 switch (E->getCastKind()) {
8092 default:
8093 return LValueExprEvaluatorBaseTy::VisitCastExpr(E);
8094
8095 case CK_LValueBitCast:
8096 this->CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
8097 if (!Visit(E->getSubExpr()))
8098 return false;
8099 Result.Designator.setInvalid();
8100 return true;
8101
8102 case CK_BaseToDerived:
8103 if (!Visit(E->getSubExpr()))
8104 return false;
8105 return HandleBaseToDerivedCast(Info, E, Result);
8106
8107 case CK_Dynamic:
8108 if (!Visit(E->getSubExpr()))
8109 return false;
8110 return HandleDynamicCast(Info, cast<ExplicitCastExpr>(E), Result);
8111 }
8112 }
8113};
8114} // end anonymous namespace
8115
8116/// Evaluate an expression as an lvalue. This can be legitimately called on
8117/// expressions which are not glvalues, in three cases:
8118/// * function designators in C, and
8119/// * "extern void" objects
8120/// * @selector() expressions in Objective-C
8121static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info,
8122 bool InvalidBaseOK) {
8123 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8123, __extension__ __PRETTY_FUNCTION__))
;
8124 assert(E->isGLValue() || E->getType()->isFunctionType() ||(static_cast <bool> (E->isGLValue() || E->getType
()->isFunctionType() || E->getType()->isVoidType() ||
isa<ObjCSelectorExpr>(E)) ? void (0) : __assert_fail (
"E->isGLValue() || E->getType()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E)"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8125, __extension__ __PRETTY_FUNCTION__))
8125 E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E))(static_cast <bool> (E->isGLValue() || E->getType
()->isFunctionType() || E->getType()->isVoidType() ||
isa<ObjCSelectorExpr>(E)) ? void (0) : __assert_fail (
"E->isGLValue() || E->getType()->isFunctionType() || E->getType()->isVoidType() || isa<ObjCSelectorExpr>(E)"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8125, __extension__ __PRETTY_FUNCTION__))
;
8126 return LValueExprEvaluator(Info, Result, InvalidBaseOK).Visit(E);
8127}
8128
8129bool LValueExprEvaluator::VisitDeclRefExpr(const DeclRefExpr *E) {
8130 const NamedDecl *D = E->getDecl();
8131 if (isa<FunctionDecl, MSGuidDecl, TemplateParamObjectDecl>(D))
8132 return Success(cast<ValueDecl>(D));
8133 if (const VarDecl *VD = dyn_cast<VarDecl>(D))
8134 return VisitVarDecl(E, VD);
8135 if (const BindingDecl *BD = dyn_cast<BindingDecl>(D))
8136 return Visit(BD->getBinding());
8137 return Error(E);
8138}
8139
8140
8141bool LValueExprEvaluator::VisitVarDecl(const Expr *E, const VarDecl *VD) {
8142
8143 // If we are within a lambda's call operator, check whether the 'VD' referred
8144 // to within 'E' actually represents a lambda-capture that maps to a
8145 // data-member/field within the closure object, and if so, evaluate to the
8146 // field or what the field refers to.
8147 if (Info.CurrentCall && isLambdaCallOperator(Info.CurrentCall->Callee) &&
8148 isa<DeclRefExpr>(E) &&
8149 cast<DeclRefExpr>(E)->refersToEnclosingVariableOrCapture()) {
8150 // We don't always have a complete capture-map when checking or inferring if
8151 // the function call operator meets the requirements of a constexpr function
8152 // - but we don't need to evaluate the captures to determine constexprness
8153 // (dcl.constexpr C++17).
8154 if (Info.checkingPotentialConstantExpression())
8155 return false;
8156
8157 if (auto *FD = Info.CurrentCall->LambdaCaptureFields.lookup(VD)) {
8158 // Start with 'Result' referring to the complete closure object...
8159 Result = *Info.CurrentCall->This;
8160 // ... then update it to refer to the field of the closure object
8161 // that represents the capture.
8162 if (!HandleLValueMember(Info, E, Result, FD))
8163 return false;
8164 // And if the field is of reference type, update 'Result' to refer to what
8165 // the field refers to.
8166 if (FD->getType()->isReferenceType()) {
8167 APValue RVal;
8168 if (!handleLValueToRValueConversion(Info, E, FD->getType(), Result,
8169 RVal))
8170 return false;
8171 Result.setFrom(Info.Ctx, RVal);
8172 }
8173 return true;
8174 }
8175 }
8176
8177 CallStackFrame *Frame = nullptr;
8178 unsigned Version = 0;
8179 if (VD->hasLocalStorage()) {
8180 // Only if a local variable was declared in the function currently being
8181 // evaluated, do we expect to be able to find its value in the current
8182 // frame. (Otherwise it was likely declared in an enclosing context and
8183 // could either have a valid evaluatable value (for e.g. a constexpr
8184 // variable) or be ill-formed (and trigger an appropriate evaluation
8185 // diagnostic)).
8186 CallStackFrame *CurrFrame = Info.CurrentCall;
8187 if (CurrFrame->Callee && CurrFrame->Callee->Equals(VD->getDeclContext())) {
8188 // Function parameters are stored in some caller's frame. (Usually the
8189 // immediate caller, but for an inherited constructor they may be more
8190 // distant.)
8191 if (auto *PVD = dyn_cast<ParmVarDecl>(VD)) {
8192 if (CurrFrame->Arguments) {
8193 VD = CurrFrame->Arguments.getOrigParam(PVD);
8194 Frame =
8195 Info.getCallFrameAndDepth(CurrFrame->Arguments.CallIndex).first;
8196 Version = CurrFrame->Arguments.Version;
8197 }
8198 } else {
8199 Frame = CurrFrame;
8200 Version = CurrFrame->getCurrentTemporaryVersion(VD);
8201 }
8202 }
8203 }
8204
8205 if (!VD->getType()->isReferenceType()) {
8206 if (Frame) {
8207 Result.set({VD, Frame->Index, Version});
8208 return true;
8209 }
8210 return Success(VD);
8211 }
8212
8213 if (!Info.getLangOpts().CPlusPlus11) {
8214 Info.CCEDiag(E, diag::note_constexpr_ltor_non_integral, 1)
8215 << VD << VD->getType();
8216 Info.Note(VD->getLocation(), diag::note_declared_at);
8217 }
8218
8219 APValue *V;
8220 if (!evaluateVarDeclInit(Info, E, VD, Frame, Version, V))
8221 return false;
8222 if (!V->hasValue()) {
8223 // FIXME: Is it possible for V to be indeterminate here? If so, we should
8224 // adjust the diagnostic to say that.
8225 if (!Info.checkingPotentialConstantExpression())
8226 Info.FFDiag(E, diag::note_constexpr_use_uninit_reference);
8227 return false;
8228 }
8229 return Success(*V, E);
8230}
8231
8232bool LValueExprEvaluator::VisitMaterializeTemporaryExpr(
8233 const MaterializeTemporaryExpr *E) {
8234 // Walk through the expression to find the materialized temporary itself.
8235 SmallVector<const Expr *, 2> CommaLHSs;
8236 SmallVector<SubobjectAdjustment, 2> Adjustments;
8237 const Expr *Inner =
8238 E->getSubExpr()->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
8239
8240 // If we passed any comma operators, evaluate their LHSs.
8241 for (unsigned I = 0, N = CommaLHSs.size(); I != N; ++I)
8242 if (!EvaluateIgnoredValue(Info, CommaLHSs[I]))
8243 return false;
8244
8245 // A materialized temporary with static storage duration can appear within the
8246 // result of a constant expression evaluation, so we need to preserve its
8247 // value for use outside this evaluation.
8248 APValue *Value;
8249 if (E->getStorageDuration() == SD_Static) {
8250 // FIXME: What about SD_Thread?
8251 Value = E->getOrCreateValue(true);
8252 *Value = APValue();
8253 Result.set(E);
8254 } else {
8255 Value = &Info.CurrentCall->createTemporary(
8256 E, E->getType(),
8257 E->getStorageDuration() == SD_FullExpression ? ScopeKind::FullExpression
8258 : ScopeKind::Block,
8259 Result);
8260 }
8261
8262 QualType Type = Inner->getType();
8263
8264 // Materialize the temporary itself.
8265 if (!EvaluateInPlace(*Value, Info, Result, Inner)) {
8266 *Value = APValue();
8267 return false;
8268 }
8269
8270 // Adjust our lvalue to refer to the desired subobject.
8271 for (unsigned I = Adjustments.size(); I != 0; /**/) {
8272 --I;
8273 switch (Adjustments[I].Kind) {
8274 case SubobjectAdjustment::DerivedToBaseAdjustment:
8275 if (!HandleLValueBasePath(Info, Adjustments[I].DerivedToBase.BasePath,
8276 Type, Result))
8277 return false;
8278 Type = Adjustments[I].DerivedToBase.BasePath->getType();
8279 break;
8280
8281 case SubobjectAdjustment::FieldAdjustment:
8282 if (!HandleLValueMember(Info, E, Result, Adjustments[I].Field))
8283 return false;
8284 Type = Adjustments[I].Field->getType();
8285 break;
8286
8287 case SubobjectAdjustment::MemberPointerAdjustment:
8288 if (!HandleMemberPointerAccess(this->Info, Type, Result,
8289 Adjustments[I].Ptr.RHS))
8290 return false;
8291 Type = Adjustments[I].Ptr.MPT->getPointeeType();
8292 break;
8293 }
8294 }
8295
8296 return true;
8297}
8298
8299bool
8300LValueExprEvaluator::VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) {
8301 assert((!Info.getLangOpts().CPlusPlus || E->isFileScope()) &&(static_cast <bool> ((!Info.getLangOpts().CPlusPlus || E
->isFileScope()) && "lvalue compound literal in c++?"
) ? void (0) : __assert_fail ("(!Info.getLangOpts().CPlusPlus || E->isFileScope()) && \"lvalue compound literal in c++?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8302, __extension__ __PRETTY_FUNCTION__))
8302 "lvalue compound literal in c++?")(static_cast <bool> ((!Info.getLangOpts().CPlusPlus || E
->isFileScope()) && "lvalue compound literal in c++?"
) ? void (0) : __assert_fail ("(!Info.getLangOpts().CPlusPlus || E->isFileScope()) && \"lvalue compound literal in c++?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8302, __extension__ __PRETTY_FUNCTION__))
;
8303 // Defer visiting the literal until the lvalue-to-rvalue conversion. We can
8304 // only see this when folding in C, so there's no standard to follow here.
8305 return Success(E);
8306}
8307
8308bool LValueExprEvaluator::VisitCXXTypeidExpr(const CXXTypeidExpr *E) {
8309 TypeInfoLValue TypeInfo;
8310
8311 if (!E->isPotentiallyEvaluated()) {
8312 if (E->isTypeOperand())
8313 TypeInfo = TypeInfoLValue(E->getTypeOperand(Info.Ctx).getTypePtr());
8314 else
8315 TypeInfo = TypeInfoLValue(E->getExprOperand()->getType().getTypePtr());
8316 } else {
8317 if (!Info.Ctx.getLangOpts().CPlusPlus20) {
8318 Info.CCEDiag(E, diag::note_constexpr_typeid_polymorphic)
8319 << E->getExprOperand()->getType()
8320 << E->getExprOperand()->getSourceRange();
8321 }
8322
8323 if (!Visit(E->getExprOperand()))
8324 return false;
8325
8326 Optional<DynamicType> DynType =
8327 ComputeDynamicType(Info, E, Result, AK_TypeId);
8328 if (!DynType)
8329 return false;
8330
8331 TypeInfo =
8332 TypeInfoLValue(Info.Ctx.getRecordType(DynType->Type).getTypePtr());
8333 }
8334
8335 return Success(APValue::LValueBase::getTypeInfo(TypeInfo, E->getType()));
8336}
8337
8338bool LValueExprEvaluator::VisitCXXUuidofExpr(const CXXUuidofExpr *E) {
8339 return Success(E->getGuidDecl());
8340}
8341
8342bool LValueExprEvaluator::VisitMemberExpr(const MemberExpr *E) {
8343 // Handle static data members.
8344 if (const VarDecl *VD = dyn_cast<VarDecl>(E->getMemberDecl())) {
8345 VisitIgnoredBaseExpression(E->getBase());
8346 return VisitVarDecl(E, VD);
8347 }
8348
8349 // Handle static member functions.
8350 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(E->getMemberDecl())) {
8351 if (MD->isStatic()) {
8352 VisitIgnoredBaseExpression(E->getBase());
8353 return Success(MD);
8354 }
8355 }
8356
8357 // Handle non-static data members.
8358 return LValueExprEvaluatorBaseTy::VisitMemberExpr(E);
8359}
8360
8361bool LValueExprEvaluator::VisitArraySubscriptExpr(const ArraySubscriptExpr *E) {
8362 // FIXME: Deal with vectors as array subscript bases.
8363 if (E->getBase()->getType()->isVectorType())
8364 return Error(E);
8365
8366 APSInt Index;
8367 bool Success = true;
8368
8369 // C++17's rules require us to evaluate the LHS first, regardless of which
8370 // side is the base.
8371 for (const Expr *SubExpr : {E->getLHS(), E->getRHS()}) {
8372 if (SubExpr == E->getBase() ? !evaluatePointer(SubExpr, Result)
8373 : !EvaluateInteger(SubExpr, Index, Info)) {
8374 if (!Info.noteFailure())
8375 return false;
8376 Success = false;
8377 }
8378 }
8379
8380 return Success &&
8381 HandleLValueArrayAdjustment(Info, E, Result, E->getType(), Index);
8382}
8383
8384bool LValueExprEvaluator::VisitUnaryDeref(const UnaryOperator *E) {
8385 return evaluatePointer(E->getSubExpr(), Result);
8386}
8387
8388bool LValueExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
8389 if (!Visit(E->getSubExpr()))
8390 return false;
8391 // __real is a no-op on scalar lvalues.
8392 if (E->getSubExpr()->getType()->isAnyComplexType())
8393 HandleLValueComplexElement(Info, E, Result, E->getType(), false);
8394 return true;
8395}
8396
8397bool LValueExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
8398 assert(E->getSubExpr()->getType()->isAnyComplexType() &&(static_cast <bool> (E->getSubExpr()->getType()->
isAnyComplexType() && "lvalue __imag__ on scalar?") ?
void (0) : __assert_fail ("E->getSubExpr()->getType()->isAnyComplexType() && \"lvalue __imag__ on scalar?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8399, __extension__ __PRETTY_FUNCTION__))
8399 "lvalue __imag__ on scalar?")(static_cast <bool> (E->getSubExpr()->getType()->
isAnyComplexType() && "lvalue __imag__ on scalar?") ?
void (0) : __assert_fail ("E->getSubExpr()->getType()->isAnyComplexType() && \"lvalue __imag__ on scalar?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8399, __extension__ __PRETTY_FUNCTION__))
;
8400 if (!Visit(E->getSubExpr()))
8401 return false;
8402 HandleLValueComplexElement(Info, E, Result, E->getType(), true);
8403 return true;
8404}
8405
8406bool LValueExprEvaluator::VisitUnaryPreIncDec(const UnaryOperator *UO) {
8407 if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
8408 return Error(UO);
8409
8410 if (!this->Visit(UO->getSubExpr()))
8411 return false;
8412
8413 return handleIncDec(
8414 this->Info, UO, Result, UO->getSubExpr()->getType(),
8415 UO->isIncrementOp(), nullptr);
8416}
8417
8418bool LValueExprEvaluator::VisitCompoundAssignOperator(
8419 const CompoundAssignOperator *CAO) {
8420 if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
8421 return Error(CAO);
8422
8423 bool Success = true;
8424
8425 // C++17 onwards require that we evaluate the RHS first.
8426 APValue RHS;
8427 if (!Evaluate(RHS, this->Info, CAO->getRHS())) {
8428 if (!Info.noteFailure())
8429 return false;
8430 Success = false;
8431 }
8432
8433 // The overall lvalue result is the result of evaluating the LHS.
8434 if (!this->Visit(CAO->getLHS()) || !Success)
8435 return false;
8436
8437 return handleCompoundAssignment(
8438 this->Info, CAO,
8439 Result, CAO->getLHS()->getType(), CAO->getComputationLHSType(),
8440 CAO->getOpForCompoundAssignment(CAO->getOpcode()), RHS);
8441}
8442
8443bool LValueExprEvaluator::VisitBinAssign(const BinaryOperator *E) {
8444 if (!Info.getLangOpts().CPlusPlus14 && !Info.keepEvaluatingAfterFailure())
8445 return Error(E);
8446
8447 bool Success = true;
8448
8449 // C++17 onwards require that we evaluate the RHS first.
8450 APValue NewVal;
8451 if (!Evaluate(NewVal, this->Info, E->getRHS())) {
8452 if (!Info.noteFailure())
8453 return false;
8454 Success = false;
8455 }
8456
8457 if (!this->Visit(E->getLHS()) || !Success)
8458 return false;
8459
8460 if (Info.getLangOpts().CPlusPlus20 &&
8461 !HandleUnionActiveMemberChange(Info, E->getLHS(), Result))
8462 return false;
8463
8464 return handleAssignment(this->Info, E, Result, E->getLHS()->getType(),
8465 NewVal);
8466}
8467
8468//===----------------------------------------------------------------------===//
8469// Pointer Evaluation
8470//===----------------------------------------------------------------------===//
8471
8472/// Attempts to compute the number of bytes available at the pointer
8473/// returned by a function with the alloc_size attribute. Returns true if we
8474/// were successful. Places an unsigned number into `Result`.
8475///
8476/// This expects the given CallExpr to be a call to a function with an
8477/// alloc_size attribute.
8478static bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx,
8479 const CallExpr *Call,
8480 llvm::APInt &Result) {
8481 const AllocSizeAttr *AllocSize = getAllocSizeAttr(Call);
8482
8483 assert(AllocSize && AllocSize->getElemSizeParam().isValid())(static_cast <bool> (AllocSize && AllocSize->
getElemSizeParam().isValid()) ? void (0) : __assert_fail ("AllocSize && AllocSize->getElemSizeParam().isValid()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8483, __extension__ __PRETTY_FUNCTION__))
;
8484 unsigned SizeArgNo = AllocSize->getElemSizeParam().getASTIndex();
8485 unsigned BitsInSizeT = Ctx.getTypeSize(Ctx.getSizeType());
8486 if (Call->getNumArgs() <= SizeArgNo)
8487 return false;
8488
8489 auto EvaluateAsSizeT = [&](const Expr *E, APSInt &Into) {
8490 Expr::EvalResult ExprResult;
8491 if (!E->EvaluateAsInt(ExprResult, Ctx, Expr::SE_AllowSideEffects))
8492 return false;
8493 Into = ExprResult.Val.getInt();
8494 if (Into.isNegative() || !Into.isIntN(BitsInSizeT))
8495 return false;
8496 Into = Into.zextOrSelf(BitsInSizeT);
8497 return true;
8498 };
8499
8500 APSInt SizeOfElem;
8501 if (!EvaluateAsSizeT(Call->getArg(SizeArgNo), SizeOfElem))
8502 return false;
8503
8504 if (!AllocSize->getNumElemsParam().isValid()) {
8505 Result = std::move(SizeOfElem);
8506 return true;
8507 }
8508
8509 APSInt NumberOfElems;
8510 unsigned NumArgNo = AllocSize->getNumElemsParam().getASTIndex();
8511 if (!EvaluateAsSizeT(Call->getArg(NumArgNo), NumberOfElems))
8512 return false;
8513
8514 bool Overflow;
8515 llvm::APInt BytesAvailable = SizeOfElem.umul_ov(NumberOfElems, Overflow);
8516 if (Overflow)
8517 return false;
8518
8519 Result = std::move(BytesAvailable);
8520 return true;
8521}
8522
8523/// Convenience function. LVal's base must be a call to an alloc_size
8524/// function.
8525static bool getBytesReturnedByAllocSizeCall(const ASTContext &Ctx,
8526 const LValue &LVal,
8527 llvm::APInt &Result) {
8528 assert(isBaseAnAllocSizeCall(LVal.getLValueBase()) &&(static_cast <bool> (isBaseAnAllocSizeCall(LVal.getLValueBase
()) && "Can't get the size of a non alloc_size function"
) ? void (0) : __assert_fail ("isBaseAnAllocSizeCall(LVal.getLValueBase()) && \"Can't get the size of a non alloc_size function\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8529, __extension__ __PRETTY_FUNCTION__))
8529 "Can't get the size of a non alloc_size function")(static_cast <bool> (isBaseAnAllocSizeCall(LVal.getLValueBase
()) && "Can't get the size of a non alloc_size function"
) ? void (0) : __assert_fail ("isBaseAnAllocSizeCall(LVal.getLValueBase()) && \"Can't get the size of a non alloc_size function\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8529, __extension__ __PRETTY_FUNCTION__))
;
8530 const auto *Base = LVal.getLValueBase().get<const Expr *>();
8531 const CallExpr *CE = tryUnwrapAllocSizeCall(Base);
8532 return getBytesReturnedByAllocSizeCall(Ctx, CE, Result);
8533}
8534
8535/// Attempts to evaluate the given LValueBase as the result of a call to
8536/// a function with the alloc_size attribute. If it was possible to do so, this
8537/// function will return true, make Result's Base point to said function call,
8538/// and mark Result's Base as invalid.
8539static bool evaluateLValueAsAllocSize(EvalInfo &Info, APValue::LValueBase Base,
8540 LValue &Result) {
8541 if (Base.isNull())
8542 return false;
8543
8544 // Because we do no form of static analysis, we only support const variables.
8545 //
8546 // Additionally, we can't support parameters, nor can we support static
8547 // variables (in the latter case, use-before-assign isn't UB; in the former,
8548 // we have no clue what they'll be assigned to).
8549 const auto *VD =
8550 dyn_cast_or_null<VarDecl>(Base.dyn_cast<const ValueDecl *>());
8551 if (!VD || !VD->isLocalVarDecl() || !VD->getType().isConstQualified())
8552 return false;
8553
8554 const Expr *Init = VD->getAnyInitializer();
8555 if (!Init)
8556 return false;
8557
8558 const Expr *E = Init->IgnoreParens();
8559 if (!tryUnwrapAllocSizeCall(E))
8560 return false;
8561
8562 // Store E instead of E unwrapped so that the type of the LValue's base is
8563 // what the user wanted.
8564 Result.setInvalid(E);
8565
8566 QualType Pointee = E->getType()->castAs<PointerType>()->getPointeeType();
8567 Result.addUnsizedArray(Info, E, Pointee);
8568 return true;
8569}
8570
8571namespace {
8572class PointerExprEvaluator
8573 : public ExprEvaluatorBase<PointerExprEvaluator> {
8574 LValue &Result;
8575 bool InvalidBaseOK;
8576
8577 bool Success(const Expr *E) {
8578 Result.set(E);
8579 return true;
8580 }
8581
8582 bool evaluateLValue(const Expr *E, LValue &Result) {
8583 return EvaluateLValue(E, Result, Info, InvalidBaseOK);
8584 }
8585
8586 bool evaluatePointer(const Expr *E, LValue &Result) {
8587 return EvaluatePointer(E, Result, Info, InvalidBaseOK);
8588 }
8589
8590 bool visitNonBuiltinCallExpr(const CallExpr *E);
8591public:
8592
8593 PointerExprEvaluator(EvalInfo &info, LValue &Result, bool InvalidBaseOK)
8594 : ExprEvaluatorBaseTy(info), Result(Result),
8595 InvalidBaseOK(InvalidBaseOK) {}
8596
8597 bool Success(const APValue &V, const Expr *E) {
8598 Result.setFrom(Info.Ctx, V);
8599 return true;
8600 }
8601 bool ZeroInitialization(const Expr *E) {
8602 Result.setNull(Info.Ctx, E->getType());
8603 return true;
8604 }
8605
8606 bool VisitBinaryOperator(const BinaryOperator *E);
8607 bool VisitCastExpr(const CastExpr* E);
8608 bool VisitUnaryAddrOf(const UnaryOperator *E);
8609 bool VisitObjCStringLiteral(const ObjCStringLiteral *E)
8610 { return Success(E); }
8611 bool VisitObjCBoxedExpr(const ObjCBoxedExpr *E) {
8612 if (E->isExpressibleAsConstantInitializer())
8613 return Success(E);
8614 if (Info.noteFailure())
8615 EvaluateIgnoredValue(Info, E->getSubExpr());
8616 return Error(E);
8617 }
8618 bool VisitAddrLabelExpr(const AddrLabelExpr *E)
8619 { return Success(E); }
8620 bool VisitCallExpr(const CallExpr *E);
8621 bool VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp);
8622 bool VisitBlockExpr(const BlockExpr *E) {
8623 if (!E->getBlockDecl()->hasCaptures())
8624 return Success(E);
8625 return Error(E);
8626 }
8627 bool VisitCXXThisExpr(const CXXThisExpr *E) {
8628 // Can't look at 'this' when checking a potential constant expression.
8629 if (Info.checkingPotentialConstantExpression())
8630 return false;
8631 if (!Info.CurrentCall->This) {
8632 if (Info.getLangOpts().CPlusPlus11)
8633 Info.FFDiag(E, diag::note_constexpr_this) << E->isImplicit();
8634 else
8635 Info.FFDiag(E);
8636 return false;
8637 }
8638 Result = *Info.CurrentCall->This;
8639 // If we are inside a lambda's call operator, the 'this' expression refers
8640 // to the enclosing '*this' object (either by value or reference) which is
8641 // either copied into the closure object's field that represents the '*this'
8642 // or refers to '*this'.
8643 if (isLambdaCallOperator(Info.CurrentCall->Callee)) {
8644 // Ensure we actually have captured 'this'. (an error will have
8645 // been previously reported if not).
8646 if (!Info.CurrentCall->LambdaThisCaptureField)
8647 return false;
8648
8649 // Update 'Result' to refer to the data member/field of the closure object
8650 // that represents the '*this' capture.
8651 if (!HandleLValueMember(Info, E, Result,
8652 Info.CurrentCall->LambdaThisCaptureField))
8653 return false;
8654 // If we captured '*this' by reference, replace the field with its referent.
8655 if (Info.CurrentCall->LambdaThisCaptureField->getType()
8656 ->isPointerType()) {
8657 APValue RVal;
8658 if (!handleLValueToRValueConversion(Info, E, E->getType(), Result,
8659 RVal))
8660 return false;
8661
8662 Result.setFrom(Info.Ctx, RVal);
8663 }
8664 }
8665 return true;
8666 }
8667
8668 bool VisitCXXNewExpr(const CXXNewExpr *E);
8669
8670 bool VisitSourceLocExpr(const SourceLocExpr *E) {
8671 assert(E->isStringType() && "SourceLocExpr isn't a pointer type?")(static_cast <bool> (E->isStringType() && "SourceLocExpr isn't a pointer type?"
) ? void (0) : __assert_fail ("E->isStringType() && \"SourceLocExpr isn't a pointer type?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8671, __extension__ __PRETTY_FUNCTION__))
;
8672 APValue LValResult = E->EvaluateInContext(
8673 Info.Ctx, Info.CurrentCall->CurSourceLocExprScope.getDefaultExpr());
8674 Result.setFrom(Info.Ctx, LValResult);
8675 return true;
8676 }
8677
8678 bool VisitSYCLUniqueStableNameExpr(const SYCLUniqueStableNameExpr *E) {
8679 std::string ResultStr = E->ComputeName(Info.Ctx);
8680
8681 QualType CharTy = Info.Ctx.CharTy.withConst();
8682 APInt Size(Info.Ctx.getTypeSize(Info.Ctx.getSizeType()),
8683 ResultStr.size() + 1);
8684 QualType ArrayTy = Info.Ctx.getConstantArrayType(CharTy, Size, nullptr,
8685 ArrayType::Normal, 0);
8686
8687 StringLiteral *SL =
8688 StringLiteral::Create(Info.Ctx, ResultStr, StringLiteral::Ascii,
8689 /*Pascal*/ false, ArrayTy, E->getLocation());
8690
8691 evaluateLValue(SL, Result);
8692 Result.addArray(Info, E, cast<ConstantArrayType>(ArrayTy));
8693 return true;
8694 }
8695
8696 // FIXME: Missing: @protocol, @selector
8697};
8698} // end anonymous namespace
8699
8700static bool EvaluatePointer(const Expr* E, LValue& Result, EvalInfo &Info,
8701 bool InvalidBaseOK) {
8702 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8702, __extension__ __PRETTY_FUNCTION__))
;
8703 assert(E->isPRValue() && E->getType()->hasPointerRepresentation())(static_cast <bool> (E->isPRValue() && E->
getType()->hasPointerRepresentation()) ? void (0) : __assert_fail
("E->isPRValue() && E->getType()->hasPointerRepresentation()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8703, __extension__ __PRETTY_FUNCTION__))
;
8704 return PointerExprEvaluator(Info, Result, InvalidBaseOK).Visit(E);
8705}
8706
8707bool PointerExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
8708 if (E->getOpcode() != BO_Add &&
8709 E->getOpcode() != BO_Sub)
8710 return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
8711
8712 const Expr *PExp = E->getLHS();
8713 const Expr *IExp = E->getRHS();
8714 if (IExp->getType()->isPointerType())
8715 std::swap(PExp, IExp);
8716
8717 bool EvalPtrOK = evaluatePointer(PExp, Result);
8718 if (!EvalPtrOK && !Info.noteFailure())
8719 return false;
8720
8721 llvm::APSInt Offset;
8722 if (!EvaluateInteger(IExp, Offset, Info) || !EvalPtrOK)
8723 return false;
8724
8725 if (E->getOpcode() == BO_Sub)
8726 negateAsSigned(Offset);
8727
8728 QualType Pointee = PExp->getType()->castAs<PointerType>()->getPointeeType();
8729 return HandleLValueArrayAdjustment(Info, E, Result, Pointee, Offset);
8730}
8731
8732bool PointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) {
8733 return evaluateLValue(E->getSubExpr(), Result);
8734}
8735
8736bool PointerExprEvaluator::VisitCastExpr(const CastExpr *E) {
8737 const Expr *SubExpr = E->getSubExpr();
8738
8739 switch (E->getCastKind()) {
8740 default:
8741 break;
8742 case CK_BitCast:
8743 case CK_CPointerToObjCPointerCast:
8744 case CK_BlockPointerToObjCPointerCast:
8745 case CK_AnyPointerToBlockPointerCast:
8746 case CK_AddressSpaceConversion:
8747 if (!Visit(SubExpr))
8748 return false;
8749 // Bitcasts to cv void* are static_casts, not reinterpret_casts, so are
8750 // permitted in constant expressions in C++11. Bitcasts from cv void* are
8751 // also static_casts, but we disallow them as a resolution to DR1312.
8752 if (!E->getType()->isVoidPointerType()) {
8753 if (!Result.InvalidBase && !Result.Designator.Invalid &&
8754 !Result.IsNullPtr &&
8755 Info.Ctx.hasSameUnqualifiedType(Result.Designator.getType(Info.Ctx),
8756 E->getType()->getPointeeType()) &&
8757 Info.getStdAllocatorCaller("allocate")) {
8758 // Inside a call to std::allocator::allocate and friends, we permit
8759 // casting from void* back to cv1 T* for a pointer that points to a
8760 // cv2 T.
8761 } else {
8762 Result.Designator.setInvalid();
8763 if (SubExpr->getType()->isVoidPointerType())
8764 CCEDiag(E, diag::note_constexpr_invalid_cast)
8765 << 3 << SubExpr->getType();
8766 else
8767 CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
8768 }
8769 }
8770 if (E->getCastKind() == CK_AddressSpaceConversion && Result.IsNullPtr)
8771 ZeroInitialization(E);
8772 return true;
8773
8774 case CK_DerivedToBase:
8775 case CK_UncheckedDerivedToBase:
8776 if (!evaluatePointer(E->getSubExpr(), Result))
8777 return false;
8778 if (!Result.Base && Result.Offset.isZero())
8779 return true;
8780
8781 // Now figure out the necessary offset to add to the base LV to get from
8782 // the derived class to the base class.
8783 return HandleLValueBasePath(Info, E, E->getSubExpr()->getType()->
8784 castAs<PointerType>()->getPointeeType(),
8785 Result);
8786
8787 case CK_BaseToDerived:
8788 if (!Visit(E->getSubExpr()))
8789 return false;
8790 if (!Result.Base && Result.Offset.isZero())
8791 return true;
8792 return HandleBaseToDerivedCast(Info, E, Result);
8793
8794 case CK_Dynamic:
8795 if (!Visit(E->getSubExpr()))
8796 return false;
8797 return HandleDynamicCast(Info, cast<ExplicitCastExpr>(E), Result);
8798
8799 case CK_NullToPointer:
8800 VisitIgnoredValue(E->getSubExpr());
8801 return ZeroInitialization(E);
8802
8803 case CK_IntegralToPointer: {
8804 CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
8805
8806 APValue Value;
8807 if (!EvaluateIntegerOrLValue(SubExpr, Value, Info))
8808 break;
8809
8810 if (Value.isInt()) {
8811 unsigned Size = Info.Ctx.getTypeSize(E->getType());
8812 uint64_t N = Value.getInt().extOrTrunc(Size).getZExtValue();
8813 Result.Base = (Expr*)nullptr;
8814 Result.InvalidBase = false;
8815 Result.Offset = CharUnits::fromQuantity(N);
8816 Result.Designator.setInvalid();
8817 Result.IsNullPtr = false;
8818 return true;
8819 } else {
8820 // Cast is of an lvalue, no need to change value.
8821 Result.setFrom(Info.Ctx, Value);
8822 return true;
8823 }
8824 }
8825
8826 case CK_ArrayToPointerDecay: {
8827 if (SubExpr->isGLValue()) {
8828 if (!evaluateLValue(SubExpr, Result))
8829 return false;
8830 } else {
8831 APValue &Value = Info.CurrentCall->createTemporary(
8832 SubExpr, SubExpr->getType(), ScopeKind::FullExpression, Result);
8833 if (!EvaluateInPlace(Value, Info, Result, SubExpr))
8834 return false;
8835 }
8836 // The result is a pointer to the first element of the array.
8837 auto *AT = Info.Ctx.getAsArrayType(SubExpr->getType());
8838 if (auto *CAT = dyn_cast<ConstantArrayType>(AT))
8839 Result.addArray(Info, E, CAT);
8840 else
8841 Result.addUnsizedArray(Info, E, AT->getElementType());
8842 return true;
8843 }
8844
8845 case CK_FunctionToPointerDecay:
8846 return evaluateLValue(SubExpr, Result);
8847
8848 case CK_LValueToRValue: {
8849 LValue LVal;
8850 if (!evaluateLValue(E->getSubExpr(), LVal))
8851 return false;
8852
8853 APValue RVal;
8854 // Note, we use the subexpression's type in order to retain cv-qualifiers.
8855 if (!handleLValueToRValueConversion(Info, E, E->getSubExpr()->getType(),
8856 LVal, RVal))
8857 return InvalidBaseOK &&
8858 evaluateLValueAsAllocSize(Info, LVal.Base, Result);
8859 return Success(RVal, E);
8860 }
8861 }
8862
8863 return ExprEvaluatorBaseTy::VisitCastExpr(E);
8864}
8865
8866static CharUnits GetAlignOfType(EvalInfo &Info, QualType T,
8867 UnaryExprOrTypeTrait ExprKind) {
8868 // C++ [expr.alignof]p3:
8869 // When alignof is applied to a reference type, the result is the
8870 // alignment of the referenced type.
8871 if (const ReferenceType *Ref = T->getAs<ReferenceType>())
8872 T = Ref->getPointeeType();
8873
8874 if (T.getQualifiers().hasUnaligned())
8875 return CharUnits::One();
8876
8877 const bool AlignOfReturnsPreferred =
8878 Info.Ctx.getLangOpts().getClangABICompat() <= LangOptions::ClangABI::Ver7;
8879
8880 // __alignof is defined to return the preferred alignment.
8881 // Before 8, clang returned the preferred alignment for alignof and _Alignof
8882 // as well.
8883 if (ExprKind == UETT_PreferredAlignOf || AlignOfReturnsPreferred)
8884 return Info.Ctx.toCharUnitsFromBits(
8885 Info.Ctx.getPreferredTypeAlign(T.getTypePtr()));
8886 // alignof and _Alignof are defined to return the ABI alignment.
8887 else if (ExprKind == UETT_AlignOf)
8888 return Info.Ctx.getTypeAlignInChars(T.getTypePtr());
8889 else
8890 llvm_unreachable("GetAlignOfType on a non-alignment ExprKind")::llvm::llvm_unreachable_internal("GetAlignOfType on a non-alignment ExprKind"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8890)
;
8891}
8892
8893static CharUnits GetAlignOfExpr(EvalInfo &Info, const Expr *E,
8894 UnaryExprOrTypeTrait ExprKind) {
8895 E = E->IgnoreParens();
8896
8897 // The kinds of expressions that we have special-case logic here for
8898 // should be kept up to date with the special checks for those
8899 // expressions in Sema.
8900
8901 // alignof decl is always accepted, even if it doesn't make sense: we default
8902 // to 1 in those cases.
8903 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
8904 return Info.Ctx.getDeclAlign(DRE->getDecl(),
8905 /*RefAsPointee*/true);
8906
8907 if (const MemberExpr *ME = dyn_cast<MemberExpr>(E))
8908 return Info.Ctx.getDeclAlign(ME->getMemberDecl(),
8909 /*RefAsPointee*/true);
8910
8911 return GetAlignOfType(Info, E->getType(), ExprKind);
8912}
8913
8914static CharUnits getBaseAlignment(EvalInfo &Info, const LValue &Value) {
8915 if (const auto *VD = Value.Base.dyn_cast<const ValueDecl *>())
8916 return Info.Ctx.getDeclAlign(VD);
8917 if (const auto *E = Value.Base.dyn_cast<const Expr *>())
8918 return GetAlignOfExpr(Info, E, UETT_AlignOf);
8919 return GetAlignOfType(Info, Value.Base.getTypeInfoType(), UETT_AlignOf);
8920}
8921
8922/// Evaluate the value of the alignment argument to __builtin_align_{up,down},
8923/// __builtin_is_aligned and __builtin_assume_aligned.
8924static bool getAlignmentArgument(const Expr *E, QualType ForType,
8925 EvalInfo &Info, APSInt &Alignment) {
8926 if (!EvaluateInteger(E, Alignment, Info))
8927 return false;
8928 if (Alignment < 0 || !Alignment.isPowerOf2()) {
8929 Info.FFDiag(E, diag::note_constexpr_invalid_alignment) << Alignment;
8930 return false;
8931 }
8932 unsigned SrcWidth = Info.Ctx.getIntWidth(ForType);
8933 APSInt MaxValue(APInt::getOneBitSet(SrcWidth, SrcWidth - 1));
8934 if (APSInt::compareValues(Alignment, MaxValue) > 0) {
8935 Info.FFDiag(E, diag::note_constexpr_alignment_too_big)
8936 << MaxValue << ForType << Alignment;
8937 return false;
8938 }
8939 // Ensure both alignment and source value have the same bit width so that we
8940 // don't assert when computing the resulting value.
8941 APSInt ExtAlignment =
8942 APSInt(Alignment.zextOrTrunc(SrcWidth), /*isUnsigned=*/true);
8943 assert(APSInt::compareValues(Alignment, ExtAlignment) == 0 &&(static_cast <bool> (APSInt::compareValues(Alignment, ExtAlignment
) == 0 && "Alignment should not be changed by ext/trunc"
) ? void (0) : __assert_fail ("APSInt::compareValues(Alignment, ExtAlignment) == 0 && \"Alignment should not be changed by ext/trunc\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8944, __extension__ __PRETTY_FUNCTION__))
8944 "Alignment should not be changed by ext/trunc")(static_cast <bool> (APSInt::compareValues(Alignment, ExtAlignment
) == 0 && "Alignment should not be changed by ext/trunc"
) ? void (0) : __assert_fail ("APSInt::compareValues(Alignment, ExtAlignment) == 0 && \"Alignment should not be changed by ext/trunc\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8944, __extension__ __PRETTY_FUNCTION__))
;
8945 Alignment = ExtAlignment;
8946 assert(Alignment.getBitWidth() == SrcWidth)(static_cast <bool> (Alignment.getBitWidth() == SrcWidth
) ? void (0) : __assert_fail ("Alignment.getBitWidth() == SrcWidth"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 8946, __extension__ __PRETTY_FUNCTION__))
;
8947 return true;
8948}
8949
8950// To be clear: this happily visits unsupported builtins. Better name welcomed.
8951bool PointerExprEvaluator::visitNonBuiltinCallExpr(const CallExpr *E) {
8952 if (ExprEvaluatorBaseTy::VisitCallExpr(E))
8953 return true;
8954
8955 if (!(InvalidBaseOK && getAllocSizeAttr(E)))
8956 return false;
8957
8958 Result.setInvalid(E);
8959 QualType PointeeTy = E->getType()->castAs<PointerType>()->getPointeeType();
8960 Result.addUnsizedArray(Info, E, PointeeTy);
8961 return true;
8962}
8963
8964bool PointerExprEvaluator::VisitCallExpr(const CallExpr *E) {
8965 if (IsStringLiteralCall(E))
8966 return Success(E);
8967
8968 if (unsigned BuiltinOp = E->getBuiltinCallee())
8969 return VisitBuiltinCallExpr(E, BuiltinOp);
8970
8971 return visitNonBuiltinCallExpr(E);
8972}
8973
8974// Determine if T is a character type for which we guarantee that
8975// sizeof(T) == 1.
8976static bool isOneByteCharacterType(QualType T) {
8977 return T->isCharType() || T->isChar8Type();
8978}
8979
8980bool PointerExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
8981 unsigned BuiltinOp) {
8982 switch (BuiltinOp) {
8983 case Builtin::BI__builtin_addressof:
8984 return evaluateLValue(E->getArg(0), Result);
8985 case Builtin::BI__builtin_assume_aligned: {
8986 // We need to be very careful here because: if the pointer does not have the
8987 // asserted alignment, then the behavior is undefined, and undefined
8988 // behavior is non-constant.
8989 if (!evaluatePointer(E->getArg(0), Result))
8990 return false;
8991
8992 LValue OffsetResult(Result);
8993 APSInt Alignment;
8994 if (!getAlignmentArgument(E->getArg(1), E->getArg(0)->getType(), Info,
8995 Alignment))
8996 return false;
8997 CharUnits Align = CharUnits::fromQuantity(Alignment.getZExtValue());
8998
8999 if (E->getNumArgs() > 2) {
9000 APSInt Offset;
9001 if (!EvaluateInteger(E->getArg(2), Offset, Info))
9002 return false;
9003
9004 int64_t AdditionalOffset = -Offset.getZExtValue();
9005 OffsetResult.Offset += CharUnits::fromQuantity(AdditionalOffset);
9006 }
9007
9008 // If there is a base object, then it must have the correct alignment.
9009 if (OffsetResult.Base) {
9010 CharUnits BaseAlignment = getBaseAlignment(Info, OffsetResult);
9011
9012 if (BaseAlignment < Align) {
9013 Result.Designator.setInvalid();
9014 // FIXME: Add support to Diagnostic for long / long long.
9015 CCEDiag(E->getArg(0),
9016 diag::note_constexpr_baa_insufficient_alignment) << 0
9017 << (unsigned)BaseAlignment.getQuantity()
9018 << (unsigned)Align.getQuantity();
9019 return false;
9020 }
9021 }
9022
9023 // The offset must also have the correct alignment.
9024 if (OffsetResult.Offset.alignTo(Align) != OffsetResult.Offset) {
9025 Result.Designator.setInvalid();
9026
9027 (OffsetResult.Base
9028 ? CCEDiag(E->getArg(0),
9029 diag::note_constexpr_baa_insufficient_alignment) << 1
9030 : CCEDiag(E->getArg(0),
9031 diag::note_constexpr_baa_value_insufficient_alignment))
9032 << (int)OffsetResult.Offset.getQuantity()
9033 << (unsigned)Align.getQuantity();
9034 return false;
9035 }
9036
9037 return true;
9038 }
9039 case Builtin::BI__builtin_align_up:
9040 case Builtin::BI__builtin_align_down: {
9041 if (!evaluatePointer(E->getArg(0), Result))
9042 return false;
9043 APSInt Alignment;
9044 if (!getAlignmentArgument(E->getArg(1), E->getArg(0)->getType(), Info,
9045 Alignment))
9046 return false;
9047 CharUnits BaseAlignment = getBaseAlignment(Info, Result);
9048 CharUnits PtrAlign = BaseAlignment.alignmentAtOffset(Result.Offset);
9049 // For align_up/align_down, we can return the same value if the alignment
9050 // is known to be greater or equal to the requested value.
9051 if (PtrAlign.getQuantity() >= Alignment)
9052 return true;
9053
9054 // The alignment could be greater than the minimum at run-time, so we cannot
9055 // infer much about the resulting pointer value. One case is possible:
9056 // For `_Alignas(32) char buf[N]; __builtin_align_down(&buf[idx], 32)` we
9057 // can infer the correct index if the requested alignment is smaller than
9058 // the base alignment so we can perform the computation on the offset.
9059 if (BaseAlignment.getQuantity() >= Alignment) {
9060 assert(Alignment.getBitWidth() <= 64 &&(static_cast <bool> (Alignment.getBitWidth() <= 64 &&
"Cannot handle > 64-bit address-space") ? void (0) : __assert_fail
("Alignment.getBitWidth() <= 64 && \"Cannot handle > 64-bit address-space\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9061, __extension__ __PRETTY_FUNCTION__))
9061 "Cannot handle > 64-bit address-space")(static_cast <bool> (Alignment.getBitWidth() <= 64 &&
"Cannot handle > 64-bit address-space") ? void (0) : __assert_fail
("Alignment.getBitWidth() <= 64 && \"Cannot handle > 64-bit address-space\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9061, __extension__ __PRETTY_FUNCTION__))
;
9062 uint64_t Alignment64 = Alignment.getZExtValue();
9063 CharUnits NewOffset = CharUnits::fromQuantity(
9064 BuiltinOp == Builtin::BI__builtin_align_down
9065 ? llvm::alignDown(Result.Offset.getQuantity(), Alignment64)
9066 : llvm::alignTo(Result.Offset.getQuantity(), Alignment64));
9067 Result.adjustOffset(NewOffset - Result.Offset);
9068 // TODO: diagnose out-of-bounds values/only allow for arrays?
9069 return true;
9070 }
9071 // Otherwise, we cannot constant-evaluate the result.
9072 Info.FFDiag(E->getArg(0), diag::note_constexpr_alignment_adjust)
9073 << Alignment;
9074 return false;
9075 }
9076 case Builtin::BI__builtin_operator_new:
9077 return HandleOperatorNewCall(Info, E, Result);
9078 case Builtin::BI__builtin_launder:
9079 return evaluatePointer(E->getArg(0), Result);
9080 case Builtin::BIstrchr:
9081 case Builtin::BIwcschr:
9082 case Builtin::BImemchr:
9083 case Builtin::BIwmemchr:
9084 if (Info.getLangOpts().CPlusPlus11)
9085 Info.CCEDiag(E, diag::note_constexpr_invalid_function)
9086 << /*isConstexpr*/0 << /*isConstructor*/0
9087 << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
9088 else
9089 Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
9090 LLVM_FALLTHROUGH[[gnu::fallthrough]];
9091 case Builtin::BI__builtin_strchr:
9092 case Builtin::BI__builtin_wcschr:
9093 case Builtin::BI__builtin_memchr:
9094 case Builtin::BI__builtin_char_memchr:
9095 case Builtin::BI__builtin_wmemchr: {
9096 if (!Visit(E->getArg(0)))
9097 return false;
9098 APSInt Desired;
9099 if (!EvaluateInteger(E->getArg(1), Desired, Info))
9100 return false;
9101 uint64_t MaxLength = uint64_t(-1);
9102 if (BuiltinOp != Builtin::BIstrchr &&
9103 BuiltinOp != Builtin::BIwcschr &&
9104 BuiltinOp != Builtin::BI__builtin_strchr &&
9105 BuiltinOp != Builtin::BI__builtin_wcschr) {
9106 APSInt N;
9107 if (!EvaluateInteger(E->getArg(2), N, Info))
9108 return false;
9109 MaxLength = N.getExtValue();
9110 }
9111 // We cannot find the value if there are no candidates to match against.
9112 if (MaxLength == 0u)
9113 return ZeroInitialization(E);
9114 if (!Result.checkNullPointerForFoldAccess(Info, E, AK_Read) ||
9115 Result.Designator.Invalid)
9116 return false;
9117 QualType CharTy = Result.Designator.getType(Info.Ctx);
9118 bool IsRawByte = BuiltinOp == Builtin::BImemchr ||
9119 BuiltinOp == Builtin::BI__builtin_memchr;
9120 assert(IsRawByte ||(static_cast <bool> (IsRawByte || Info.Ctx.hasSameUnqualifiedType
( CharTy, E->getArg(0)->getType()->getPointeeType())
) ? void (0) : __assert_fail ("IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E->getArg(0)->getType()->getPointeeType())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9122, __extension__ __PRETTY_FUNCTION__))
9121 Info.Ctx.hasSameUnqualifiedType((static_cast <bool> (IsRawByte || Info.Ctx.hasSameUnqualifiedType
( CharTy, E->getArg(0)->getType()->getPointeeType())
) ? void (0) : __assert_fail ("IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E->getArg(0)->getType()->getPointeeType())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9122, __extension__ __PRETTY_FUNCTION__))
9122 CharTy, E->getArg(0)->getType()->getPointeeType()))(static_cast <bool> (IsRawByte || Info.Ctx.hasSameUnqualifiedType
( CharTy, E->getArg(0)->getType()->getPointeeType())
) ? void (0) : __assert_fail ("IsRawByte || Info.Ctx.hasSameUnqualifiedType( CharTy, E->getArg(0)->getType()->getPointeeType())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9122, __extension__ __PRETTY_FUNCTION__))
;
9123 // Pointers to const void may point to objects of incomplete type.
9124 if (IsRawByte && CharTy->isIncompleteType()) {
9125 Info.FFDiag(E, diag::note_constexpr_ltor_incomplete_type) << CharTy;
9126 return false;
9127 }
9128 // Give up on byte-oriented matching against multibyte elements.
9129 // FIXME: We can compare the bytes in the correct order.
9130 if (IsRawByte && !isOneByteCharacterType(CharTy)) {
9131 Info.FFDiag(E, diag::note_constexpr_memchr_unsupported)
9132 << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'")
9133 << CharTy;
9134 return false;
9135 }
9136 // Figure out what value we're actually looking for (after converting to
9137 // the corresponding unsigned type if necessary).
9138 uint64_t DesiredVal;
9139 bool StopAtNull = false;
9140 switch (BuiltinOp) {
9141 case Builtin::BIstrchr:
9142 case Builtin::BI__builtin_strchr:
9143 // strchr compares directly to the passed integer, and therefore
9144 // always fails if given an int that is not a char.
9145 if (!APSInt::isSameValue(HandleIntToIntCast(Info, E, CharTy,
9146 E->getArg(1)->getType(),
9147 Desired),
9148 Desired))
9149 return ZeroInitialization(E);
9150 StopAtNull = true;
9151 LLVM_FALLTHROUGH[[gnu::fallthrough]];
9152 case Builtin::BImemchr:
9153 case Builtin::BI__builtin_memchr:
9154 case Builtin::BI__builtin_char_memchr:
9155 // memchr compares by converting both sides to unsigned char. That's also
9156 // correct for strchr if we get this far (to cope with plain char being
9157 // unsigned in the strchr case).
9158 DesiredVal = Desired.trunc(Info.Ctx.getCharWidth()).getZExtValue();
9159 break;
9160
9161 case Builtin::BIwcschr:
9162 case Builtin::BI__builtin_wcschr:
9163 StopAtNull = true;
9164 LLVM_FALLTHROUGH[[gnu::fallthrough]];
9165 case Builtin::BIwmemchr:
9166 case Builtin::BI__builtin_wmemchr:
9167 // wcschr and wmemchr are given a wchar_t to look for. Just use it.
9168 DesiredVal = Desired.getZExtValue();
9169 break;
9170 }
9171
9172 for (; MaxLength; --MaxLength) {
9173 APValue Char;
9174 if (!handleLValueToRValueConversion(Info, E, CharTy, Result, Char) ||
9175 !Char.isInt())
9176 return false;
9177 if (Char.getInt().getZExtValue() == DesiredVal)
9178 return true;
9179 if (StopAtNull && !Char.getInt())
9180 break;
9181 if (!HandleLValueArrayAdjustment(Info, E, Result, CharTy, 1))
9182 return false;
9183 }
9184 // Not found: return nullptr.
9185 return ZeroInitialization(E);
9186 }
9187
9188 case Builtin::BImemcpy:
9189 case Builtin::BImemmove:
9190 case Builtin::BIwmemcpy:
9191 case Builtin::BIwmemmove:
9192 if (Info.getLangOpts().CPlusPlus11)
9193 Info.CCEDiag(E, diag::note_constexpr_invalid_function)
9194 << /*isConstexpr*/0 << /*isConstructor*/0
9195 << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
9196 else
9197 Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
9198 LLVM_FALLTHROUGH[[gnu::fallthrough]];
9199 case Builtin::BI__builtin_memcpy:
9200 case Builtin::BI__builtin_memmove:
9201 case Builtin::BI__builtin_wmemcpy:
9202 case Builtin::BI__builtin_wmemmove: {
9203 bool WChar = BuiltinOp == Builtin::BIwmemcpy ||
9204 BuiltinOp == Builtin::BIwmemmove ||
9205 BuiltinOp == Builtin::BI__builtin_wmemcpy ||
9206 BuiltinOp == Builtin::BI__builtin_wmemmove;
9207 bool Move = BuiltinOp == Builtin::BImemmove ||
9208 BuiltinOp == Builtin::BIwmemmove ||
9209 BuiltinOp == Builtin::BI__builtin_memmove ||
9210 BuiltinOp == Builtin::BI__builtin_wmemmove;
9211
9212 // The result of mem* is the first argument.
9213 if (!Visit(E->getArg(0)))
9214 return false;
9215 LValue Dest = Result;
9216
9217 LValue Src;
9218 if (!EvaluatePointer(E->getArg(1), Src, Info))
9219 return false;
9220
9221 APSInt N;
9222 if (!EvaluateInteger(E->getArg(2), N, Info))
9223 return false;
9224 assert(!N.isSigned() && "memcpy and friends take an unsigned size")(static_cast <bool> (!N.isSigned() && "memcpy and friends take an unsigned size"
) ? void (0) : __assert_fail ("!N.isSigned() && \"memcpy and friends take an unsigned size\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9224, __extension__ __PRETTY_FUNCTION__))
;
9225
9226 // If the size is zero, we treat this as always being a valid no-op.
9227 // (Even if one of the src and dest pointers is null.)
9228 if (!N)
9229 return true;
9230
9231 // Otherwise, if either of the operands is null, we can't proceed. Don't
9232 // try to determine the type of the copied objects, because there aren't
9233 // any.
9234 if (!Src.Base || !Dest.Base) {
9235 APValue Val;
9236 (!Src.Base ? Src : Dest).moveInto(Val);
9237 Info.FFDiag(E, diag::note_constexpr_memcpy_null)
9238 << Move << WChar << !!Src.Base
9239 << Val.getAsString(Info.Ctx, E->getArg(0)->getType());
9240 return false;
9241 }
9242 if (Src.Designator.Invalid || Dest.Designator.Invalid)
9243 return false;
9244
9245 // We require that Src and Dest are both pointers to arrays of
9246 // trivially-copyable type. (For the wide version, the designator will be
9247 // invalid if the designated object is not a wchar_t.)
9248 QualType T = Dest.Designator.getType(Info.Ctx);
9249 QualType SrcT = Src.Designator.getType(Info.Ctx);
9250 if (!Info.Ctx.hasSameUnqualifiedType(T, SrcT)) {
9251 // FIXME: Consider using our bit_cast implementation to support this.
9252 Info.FFDiag(E, diag::note_constexpr_memcpy_type_pun) << Move << SrcT << T;
9253 return false;
9254 }
9255 if (T->isIncompleteType()) {
9256 Info.FFDiag(E, diag::note_constexpr_memcpy_incomplete_type) << Move << T;
9257 return false;
9258 }
9259 if (!T.isTriviallyCopyableType(Info.Ctx)) {
9260 Info.FFDiag(E, diag::note_constexpr_memcpy_nontrivial) << Move << T;
9261 return false;
9262 }
9263
9264 // Figure out how many T's we're copying.
9265 uint64_t TSize = Info.Ctx.getTypeSizeInChars(T).getQuantity();
9266 if (!WChar) {
9267 uint64_t Remainder;
9268 llvm::APInt OrigN = N;
9269 llvm::APInt::udivrem(OrigN, TSize, N, Remainder);
9270 if (Remainder) {
9271 Info.FFDiag(E, diag::note_constexpr_memcpy_unsupported)
9272 << Move << WChar << 0 << T << toString(OrigN, 10, /*Signed*/false)
9273 << (unsigned)TSize;
9274 return false;
9275 }
9276 }
9277
9278 // Check that the copying will remain within the arrays, just so that we
9279 // can give a more meaningful diagnostic. This implicitly also checks that
9280 // N fits into 64 bits.
9281 uint64_t RemainingSrcSize = Src.Designator.validIndexAdjustments().second;
9282 uint64_t RemainingDestSize = Dest.Designator.validIndexAdjustments().second;
9283 if (N.ugt(RemainingSrcSize) || N.ugt(RemainingDestSize)) {
9284 Info.FFDiag(E, diag::note_constexpr_memcpy_unsupported)
9285 << Move << WChar << (N.ugt(RemainingSrcSize) ? 1 : 2) << T
9286 << toString(N, 10, /*Signed*/false);
9287 return false;
9288 }
9289 uint64_t NElems = N.getZExtValue();
9290 uint64_t NBytes = NElems * TSize;
9291
9292 // Check for overlap.
9293 int Direction = 1;
9294 if (HasSameBase(Src, Dest)) {
9295 uint64_t SrcOffset = Src.getLValueOffset().getQuantity();
9296 uint64_t DestOffset = Dest.getLValueOffset().getQuantity();
9297 if (DestOffset >= SrcOffset && DestOffset - SrcOffset < NBytes) {
9298 // Dest is inside the source region.
9299 if (!Move) {
9300 Info.FFDiag(E, diag::note_constexpr_memcpy_overlap) << WChar;
9301 return false;
9302 }
9303 // For memmove and friends, copy backwards.
9304 if (!HandleLValueArrayAdjustment(Info, E, Src, T, NElems - 1) ||
9305 !HandleLValueArrayAdjustment(Info, E, Dest, T, NElems - 1))
9306 return false;
9307 Direction = -1;
9308 } else if (!Move && SrcOffset >= DestOffset &&
9309 SrcOffset - DestOffset < NBytes) {
9310 // Src is inside the destination region for memcpy: invalid.
9311 Info.FFDiag(E, diag::note_constexpr_memcpy_overlap) << WChar;
9312 return false;
9313 }
9314 }
9315
9316 while (true) {
9317 APValue Val;
9318 // FIXME: Set WantObjectRepresentation to true if we're copying a
9319 // char-like type?
9320 if (!handleLValueToRValueConversion(Info, E, T, Src, Val) ||
9321 !handleAssignment(Info, E, Dest, T, Val))
9322 return false;
9323 // Do not iterate past the last element; if we're copying backwards, that
9324 // might take us off the start of the array.
9325 if (--NElems == 0)
9326 return true;
9327 if (!HandleLValueArrayAdjustment(Info, E, Src, T, Direction) ||
9328 !HandleLValueArrayAdjustment(Info, E, Dest, T, Direction))
9329 return false;
9330 }
9331 }
9332
9333 default:
9334 break;
9335 }
9336
9337 return visitNonBuiltinCallExpr(E);
9338}
9339
9340static bool EvaluateArrayNewInitList(EvalInfo &Info, LValue &This,
9341 APValue &Result, const InitListExpr *ILE,
9342 QualType AllocType);
9343static bool EvaluateArrayNewConstructExpr(EvalInfo &Info, LValue &This,
9344 APValue &Result,
9345 const CXXConstructExpr *CCE,
9346 QualType AllocType);
9347
9348bool PointerExprEvaluator::VisitCXXNewExpr(const CXXNewExpr *E) {
9349 if (!Info.getLangOpts().CPlusPlus20)
9350 Info.CCEDiag(E, diag::note_constexpr_new);
9351
9352 // We cannot speculatively evaluate a delete expression.
9353 if (Info.SpeculativeEvaluationDepth)
9354 return false;
9355
9356 FunctionDecl *OperatorNew = E->getOperatorNew();
9357
9358 bool IsNothrow = false;
9359 bool IsPlacement = false;
9360 if (OperatorNew->isReservedGlobalPlacementOperator() &&
9361 Info.CurrentCall->isStdFunction() && !E->isArray()) {
9362 // FIXME Support array placement new.
9363 assert(E->getNumPlacementArgs() == 1)(static_cast <bool> (E->getNumPlacementArgs() == 1) ?
void (0) : __assert_fail ("E->getNumPlacementArgs() == 1"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9363, __extension__ __PRETTY_FUNCTION__))
;
9364 if (!EvaluatePointer(E->getPlacementArg(0), Result, Info))
9365 return false;
9366 if (Result.Designator.Invalid)
9367 return false;
9368 IsPlacement = true;
9369 } else if (!OperatorNew->isReplaceableGlobalAllocationFunction()) {
9370 Info.FFDiag(E, diag::note_constexpr_new_non_replaceable)
9371 << isa<CXXMethodDecl>(OperatorNew) << OperatorNew;
9372 return false;
9373 } else if (E->getNumPlacementArgs()) {
9374 // The only new-placement list we support is of the form (std::nothrow).
9375 //
9376 // FIXME: There is no restriction on this, but it's not clear that any
9377 // other form makes any sense. We get here for cases such as:
9378 //
9379 // new (std::align_val_t{N}) X(int)
9380 //
9381 // (which should presumably be valid only if N is a multiple of
9382 // alignof(int), and in any case can't be deallocated unless N is
9383 // alignof(X) and X has new-extended alignment).
9384 if (E->getNumPlacementArgs() != 1 ||
9385 !E->getPlacementArg(0)->getType()->isNothrowT())
9386 return Error(E, diag::note_constexpr_new_placement);
9387
9388 LValue Nothrow;
9389 if (!EvaluateLValue(E->getPlacementArg(0), Nothrow, Info))
9390 return false;
9391 IsNothrow = true;
9392 }
9393
9394 const Expr *Init = E->getInitializer();
9395 const InitListExpr *ResizedArrayILE = nullptr;
9396 const CXXConstructExpr *ResizedArrayCCE = nullptr;
9397 bool ValueInit = false;
9398
9399 QualType AllocType = E->getAllocatedType();
9400 if (Optional<const Expr*> ArraySize = E->getArraySize()) {
9401 const Expr *Stripped = *ArraySize;
9402 for (; auto *ICE = dyn_cast<ImplicitCastExpr>(Stripped);
9403 Stripped = ICE->getSubExpr())
9404 if (ICE->getCastKind() != CK_NoOp &&
9405 ICE->getCastKind() != CK_IntegralCast)
9406 break;
9407
9408 llvm::APSInt ArrayBound;
9409 if (!EvaluateInteger(Stripped, ArrayBound, Info))
9410 return false;
9411
9412 // C++ [expr.new]p9:
9413 // The expression is erroneous if:
9414 // -- [...] its value before converting to size_t [or] applying the
9415 // second standard conversion sequence is less than zero
9416 if (ArrayBound.isSigned() && ArrayBound.isNegative()) {
9417 if (IsNothrow)
9418 return ZeroInitialization(E);
9419
9420 Info.FFDiag(*ArraySize, diag::note_constexpr_new_negative)
9421 << ArrayBound << (*ArraySize)->getSourceRange();
9422 return false;
9423 }
9424
9425 // -- its value is such that the size of the allocated object would
9426 // exceed the implementation-defined limit
9427 if (ConstantArrayType::getNumAddressingBits(Info.Ctx, AllocType,
9428 ArrayBound) >
9429 ConstantArrayType::getMaxSizeBits(Info.Ctx)) {
9430 if (IsNothrow)
9431 return ZeroInitialization(E);
9432
9433 Info.FFDiag(*ArraySize, diag::note_constexpr_new_too_large)
9434 << ArrayBound << (*ArraySize)->getSourceRange();
9435 return false;
9436 }
9437
9438 // -- the new-initializer is a braced-init-list and the number of
9439 // array elements for which initializers are provided [...]
9440 // exceeds the number of elements to initialize
9441 if (!Init) {
9442 // No initialization is performed.
9443 } else if (isa<CXXScalarValueInitExpr>(Init) ||
9444 isa<ImplicitValueInitExpr>(Init)) {
9445 ValueInit = true;
9446 } else if (auto *CCE = dyn_cast<CXXConstructExpr>(Init)) {
9447 ResizedArrayCCE = CCE;
9448 } else {
9449 auto *CAT = Info.Ctx.getAsConstantArrayType(Init->getType());
9450 assert(CAT && "unexpected type for array initializer")(static_cast <bool> (CAT && "unexpected type for array initializer"
) ? void (0) : __assert_fail ("CAT && \"unexpected type for array initializer\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9450, __extension__ __PRETTY_FUNCTION__))
;
9451
9452 unsigned Bits =
9453 std::max(CAT->getSize().getBitWidth(), ArrayBound.getBitWidth());
9454 llvm::APInt InitBound = CAT->getSize().zextOrSelf(Bits);
9455 llvm::APInt AllocBound = ArrayBound.zextOrSelf(Bits);
9456 if (InitBound.ugt(AllocBound)) {
9457 if (IsNothrow)
9458 return ZeroInitialization(E);
9459
9460 Info.FFDiag(*ArraySize, diag::note_constexpr_new_too_small)
9461 << toString(AllocBound, 10, /*Signed=*/false)
9462 << toString(InitBound, 10, /*Signed=*/false)
9463 << (*ArraySize)->getSourceRange();
9464 return false;
9465 }
9466
9467 // If the sizes differ, we must have an initializer list, and we need
9468 // special handling for this case when we initialize.
9469 if (InitBound != AllocBound)
9470 ResizedArrayILE = cast<InitListExpr>(Init);
9471 }
9472
9473 AllocType = Info.Ctx.getConstantArrayType(AllocType, ArrayBound, nullptr,
9474 ArrayType::Normal, 0);
9475 } else {
9476 assert(!AllocType->isArrayType() &&(static_cast <bool> (!AllocType->isArrayType() &&
"array allocation with non-array new") ? void (0) : __assert_fail
("!AllocType->isArrayType() && \"array allocation with non-array new\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9477, __extension__ __PRETTY_FUNCTION__))
9477 "array allocation with non-array new")(static_cast <bool> (!AllocType->isArrayType() &&
"array allocation with non-array new") ? void (0) : __assert_fail
("!AllocType->isArrayType() && \"array allocation with non-array new\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9477, __extension__ __PRETTY_FUNCTION__))
;
9478 }
9479
9480 APValue *Val;
9481 if (IsPlacement) {
9482 AccessKinds AK = AK_Construct;
9483 struct FindObjectHandler {
9484 EvalInfo &Info;
9485 const Expr *E;
9486 QualType AllocType;
9487 const AccessKinds AccessKind;
9488 APValue *Value;
9489
9490 typedef bool result_type;
9491 bool failed() { return false; }
9492 bool found(APValue &Subobj, QualType SubobjType) {
9493 // FIXME: Reject the cases where [basic.life]p8 would not permit the
9494 // old name of the object to be used to name the new object.
9495 if (!Info.Ctx.hasSameUnqualifiedType(SubobjType, AllocType)) {
9496 Info.FFDiag(E, diag::note_constexpr_placement_new_wrong_type) <<
9497 SubobjType << AllocType;
9498 return false;
9499 }
9500 Value = &Subobj;
9501 return true;
9502 }
9503 bool found(APSInt &Value, QualType SubobjType) {
9504 Info.FFDiag(E, diag::note_constexpr_construct_complex_elem);
9505 return false;
9506 }
9507 bool found(APFloat &Value, QualType SubobjType) {
9508 Info.FFDiag(E, diag::note_constexpr_construct_complex_elem);
9509 return false;
9510 }
9511 } Handler = {Info, E, AllocType, AK, nullptr};
9512
9513 CompleteObject Obj = findCompleteObject(Info, E, AK, Result, AllocType);
9514 if (!Obj || !findSubobject(Info, E, Obj, Result.Designator, Handler))
9515 return false;
9516
9517 Val = Handler.Value;
9518
9519 // [basic.life]p1:
9520 // The lifetime of an object o of type T ends when [...] the storage
9521 // which the object occupies is [...] reused by an object that is not
9522 // nested within o (6.6.2).
9523 *Val = APValue();
9524 } else {
9525 // Perform the allocation and obtain a pointer to the resulting object.
9526 Val = Info.createHeapAlloc(E, AllocType, Result);
9527 if (!Val)
9528 return false;
9529 }
9530
9531 if (ValueInit) {
9532 ImplicitValueInitExpr VIE(AllocType);
9533 if (!EvaluateInPlace(*Val, Info, Result, &VIE))
9534 return false;
9535 } else if (ResizedArrayILE) {
9536 if (!EvaluateArrayNewInitList(Info, Result, *Val, ResizedArrayILE,
9537 AllocType))
9538 return false;
9539 } else if (ResizedArrayCCE) {
9540 if (!EvaluateArrayNewConstructExpr(Info, Result, *Val, ResizedArrayCCE,
9541 AllocType))
9542 return false;
9543 } else if (Init) {
9544 if (!EvaluateInPlace(*Val, Info, Result, Init))
9545 return false;
9546 } else if (!getDefaultInitValue(AllocType, *Val)) {
9547 return false;
9548 }
9549
9550 // Array new returns a pointer to the first element, not a pointer to the
9551 // array.
9552 if (auto *AT = AllocType->getAsArrayTypeUnsafe())
9553 Result.addArray(Info, E, cast<ConstantArrayType>(AT));
9554
9555 return true;
9556}
9557//===----------------------------------------------------------------------===//
9558// Member Pointer Evaluation
9559//===----------------------------------------------------------------------===//
9560
9561namespace {
9562class MemberPointerExprEvaluator
9563 : public ExprEvaluatorBase<MemberPointerExprEvaluator> {
9564 MemberPtr &Result;
9565
9566 bool Success(const ValueDecl *D) {
9567 Result = MemberPtr(D);
9568 return true;
9569 }
9570public:
9571
9572 MemberPointerExprEvaluator(EvalInfo &Info, MemberPtr &Result)
9573 : ExprEvaluatorBaseTy(Info), Result(Result) {}
9574
9575 bool Success(const APValue &V, const Expr *E) {
9576 Result.setFrom(V);
9577 return true;
9578 }
9579 bool ZeroInitialization(const Expr *E) {
9580 return Success((const ValueDecl*)nullptr);
9581 }
9582
9583 bool VisitCastExpr(const CastExpr *E);
9584 bool VisitUnaryAddrOf(const UnaryOperator *E);
9585};
9586} // end anonymous namespace
9587
9588static bool EvaluateMemberPointer(const Expr *E, MemberPtr &Result,
9589 EvalInfo &Info) {
9590 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9590, __extension__ __PRETTY_FUNCTION__))
;
9591 assert(E->isPRValue() && E->getType()->isMemberPointerType())(static_cast <bool> (E->isPRValue() && E->
getType()->isMemberPointerType()) ? void (0) : __assert_fail
("E->isPRValue() && E->getType()->isMemberPointerType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9591, __extension__ __PRETTY_FUNCTION__))
;
9592 return MemberPointerExprEvaluator(Info, Result).Visit(E);
9593}
9594
9595bool MemberPointerExprEvaluator::VisitCastExpr(const CastExpr *E) {
9596 switch (E->getCastKind()) {
9597 default:
9598 return ExprEvaluatorBaseTy::VisitCastExpr(E);
9599
9600 case CK_NullToMemberPointer:
9601 VisitIgnoredValue(E->getSubExpr());
9602 return ZeroInitialization(E);
9603
9604 case CK_BaseToDerivedMemberPointer: {
9605 if (!Visit(E->getSubExpr()))
9606 return false;
9607 if (E->path_empty())
9608 return true;
9609 // Base-to-derived member pointer casts store the path in derived-to-base
9610 // order, so iterate backwards. The CXXBaseSpecifier also provides us with
9611 // the wrong end of the derived->base arc, so stagger the path by one class.
9612 typedef std::reverse_iterator<CastExpr::path_const_iterator> ReverseIter;
9613 for (ReverseIter PathI(E->path_end() - 1), PathE(E->path_begin());
9614 PathI != PathE; ++PathI) {
9615 assert(!(*PathI)->isVirtual() && "memptr cast through vbase")(static_cast <bool> (!(*PathI)->isVirtual() &&
"memptr cast through vbase") ? void (0) : __assert_fail ("!(*PathI)->isVirtual() && \"memptr cast through vbase\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9615, __extension__ __PRETTY_FUNCTION__))
;
9616 const CXXRecordDecl *Derived = (*PathI)->getType()->getAsCXXRecordDecl();
9617 if (!Result.castToDerived(Derived))
9618 return Error(E);
9619 }
9620 const Type *FinalTy = E->getType()->castAs<MemberPointerType>()->getClass();
9621 if (!Result.castToDerived(FinalTy->getAsCXXRecordDecl()))
9622 return Error(E);
9623 return true;
9624 }
9625
9626 case CK_DerivedToBaseMemberPointer:
9627 if (!Visit(E->getSubExpr()))
9628 return false;
9629 for (CastExpr::path_const_iterator PathI = E->path_begin(),
9630 PathE = E->path_end(); PathI != PathE; ++PathI) {
9631 assert(!(*PathI)->isVirtual() && "memptr cast through vbase")(static_cast <bool> (!(*PathI)->isVirtual() &&
"memptr cast through vbase") ? void (0) : __assert_fail ("!(*PathI)->isVirtual() && \"memptr cast through vbase\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9631, __extension__ __PRETTY_FUNCTION__))
;
9632 const CXXRecordDecl *Base = (*PathI)->getType()->getAsCXXRecordDecl();
9633 if (!Result.castToBase(Base))
9634 return Error(E);
9635 }
9636 return true;
9637 }
9638}
9639
9640bool MemberPointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) {
9641 // C++11 [expr.unary.op]p3 has very strict rules on how the address of a
9642 // member can be formed.
9643 return Success(cast<DeclRefExpr>(E->getSubExpr())->getDecl());
9644}
9645
9646//===----------------------------------------------------------------------===//
9647// Record Evaluation
9648//===----------------------------------------------------------------------===//
9649
9650namespace {
9651 class RecordExprEvaluator
9652 : public ExprEvaluatorBase<RecordExprEvaluator> {
9653 const LValue &This;
9654 APValue &Result;
9655 public:
9656
9657 RecordExprEvaluator(EvalInfo &info, const LValue &This, APValue &Result)
9658 : ExprEvaluatorBaseTy(info), This(This), Result(Result) {}
9659
9660 bool Success(const APValue &V, const Expr *E) {
9661 Result = V;
9662 return true;
9663 }
9664 bool ZeroInitialization(const Expr *E) {
9665 return ZeroInitialization(E, E->getType());
9666 }
9667 bool ZeroInitialization(const Expr *E, QualType T);
9668
9669 bool VisitCallExpr(const CallExpr *E) {
9670 return handleCallExpr(E, Result, &This);
9671 }
9672 bool VisitCastExpr(const CastExpr *E);
9673 bool VisitInitListExpr(const InitListExpr *E);
9674 bool VisitCXXConstructExpr(const CXXConstructExpr *E) {
9675 return VisitCXXConstructExpr(E, E->getType());
9676 }
9677 bool VisitLambdaExpr(const LambdaExpr *E);
9678 bool VisitCXXInheritedCtorInitExpr(const CXXInheritedCtorInitExpr *E);
9679 bool VisitCXXConstructExpr(const CXXConstructExpr *E, QualType T);
9680 bool VisitCXXStdInitializerListExpr(const CXXStdInitializerListExpr *E);
9681 bool VisitBinCmp(const BinaryOperator *E);
9682 };
9683}
9684
9685/// Perform zero-initialization on an object of non-union class type.
9686/// C++11 [dcl.init]p5:
9687/// To zero-initialize an object or reference of type T means:
9688/// [...]
9689/// -- if T is a (possibly cv-qualified) non-union class type,
9690/// each non-static data member and each base-class subobject is
9691/// zero-initialized
9692static bool HandleClassZeroInitialization(EvalInfo &Info, const Expr *E,
9693 const RecordDecl *RD,
9694 const LValue &This, APValue &Result) {
9695 assert(!RD->isUnion() && "Expected non-union class type")(static_cast <bool> (!RD->isUnion() && "Expected non-union class type"
) ? void (0) : __assert_fail ("!RD->isUnion() && \"Expected non-union class type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9695, __extension__ __PRETTY_FUNCTION__))
;
9696 const CXXRecordDecl *CD = dyn_cast<CXXRecordDecl>(RD);
9697 Result = APValue(APValue::UninitStruct(), CD ? CD->getNumBases() : 0,
9698 std::distance(RD->field_begin(), RD->field_end()));
9699
9700 if (RD->isInvalidDecl()) return false;
9701 const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
9702
9703 if (CD) {
9704 unsigned Index = 0;
9705 for (CXXRecordDecl::base_class_const_iterator I = CD->bases_begin(),
9706 End = CD->bases_end(); I != End; ++I, ++Index) {
9707 const CXXRecordDecl *Base = I->getType()->getAsCXXRecordDecl();
9708 LValue Subobject = This;
9709 if (!HandleLValueDirectBase(Info, E, Subobject, CD, Base, &Layout))
9710 return false;
9711 if (!HandleClassZeroInitialization(Info, E, Base, Subobject,
9712 Result.getStructBase(Index)))
9713 return false;
9714 }
9715 }
9716
9717 for (const auto *I : RD->fields()) {
9718 // -- if T is a reference type, no initialization is performed.
9719 if (I->isUnnamedBitfield() || I->getType()->isReferenceType())
9720 continue;
9721
9722 LValue Subobject = This;
9723 if (!HandleLValueMember(Info, E, Subobject, I, &Layout))
9724 return false;
9725
9726 ImplicitValueInitExpr VIE(I->getType());
9727 if (!EvaluateInPlace(
9728 Result.getStructField(I->getFieldIndex()), Info, Subobject, &VIE))
9729 return false;
9730 }
9731
9732 return true;
9733}
9734
9735bool RecordExprEvaluator::ZeroInitialization(const Expr *E, QualType T) {
9736 const RecordDecl *RD = T->castAs<RecordType>()->getDecl();
9737 if (RD->isInvalidDecl()) return false;
9738 if (RD->isUnion()) {
9739 // C++11 [dcl.init]p5: If T is a (possibly cv-qualified) union type, the
9740 // object's first non-static named data member is zero-initialized
9741 RecordDecl::field_iterator I = RD->field_begin();
9742 while (I != RD->field_end() && (*I)->isUnnamedBitfield())
9743 ++I;
9744 if (I == RD->field_end()) {
9745 Result = APValue((const FieldDecl*)nullptr);
9746 return true;
9747 }
9748
9749 LValue Subobject = This;
9750 if (!HandleLValueMember(Info, E, Subobject, *I))
9751 return false;
9752 Result = APValue(*I);
9753 ImplicitValueInitExpr VIE(I->getType());
9754 return EvaluateInPlace(Result.getUnionValue(), Info, Subobject, &VIE);
9755 }
9756
9757 if (isa<CXXRecordDecl>(RD) && cast<CXXRecordDecl>(RD)->getNumVBases()) {
9758 Info.FFDiag(E, diag::note_constexpr_virtual_base) << RD;
9759 return false;
9760 }
9761
9762 return HandleClassZeroInitialization(Info, E, RD, This, Result);
9763}
9764
9765bool RecordExprEvaluator::VisitCastExpr(const CastExpr *E) {
9766 switch (E->getCastKind()) {
9767 default:
9768 return ExprEvaluatorBaseTy::VisitCastExpr(E);
9769
9770 case CK_ConstructorConversion:
9771 return Visit(E->getSubExpr());
9772
9773 case CK_DerivedToBase:
9774 case CK_UncheckedDerivedToBase: {
9775 APValue DerivedObject;
9776 if (!Evaluate(DerivedObject, Info, E->getSubExpr()))
9777 return false;
9778 if (!DerivedObject.isStruct())
9779 return Error(E->getSubExpr());
9780
9781 // Derived-to-base rvalue conversion: just slice off the derived part.
9782 APValue *Value = &DerivedObject;
9783 const CXXRecordDecl *RD = E->getSubExpr()->getType()->getAsCXXRecordDecl();
9784 for (CastExpr::path_const_iterator PathI = E->path_begin(),
9785 PathE = E->path_end(); PathI != PathE; ++PathI) {
9786 assert(!(*PathI)->isVirtual() && "record rvalue with virtual base")(static_cast <bool> (!(*PathI)->isVirtual() &&
"record rvalue with virtual base") ? void (0) : __assert_fail
("!(*PathI)->isVirtual() && \"record rvalue with virtual base\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9786, __extension__ __PRETTY_FUNCTION__))
;
9787 const CXXRecordDecl *Base = (*PathI)->getType()->getAsCXXRecordDecl();
9788 Value = &Value->getStructBase(getBaseIndex(RD, Base));
9789 RD = Base;
9790 }
9791 Result = *Value;
9792 return true;
9793 }
9794 }
9795}
9796
9797bool RecordExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
9798 if (E->isTransparent())
9799 return Visit(E->getInit(0));
9800
9801 const RecordDecl *RD = E->getType()->castAs<RecordType>()->getDecl();
9802 if (RD->isInvalidDecl()) return false;
9803 const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(RD);
9804 auto *CXXRD = dyn_cast<CXXRecordDecl>(RD);
9805
9806 EvalInfo::EvaluatingConstructorRAII EvalObj(
9807 Info,
9808 ObjectUnderConstruction{This.getLValueBase(), This.Designator.Entries},
9809 CXXRD && CXXRD->getNumBases());
9810
9811 if (RD->isUnion()) {
9812 const FieldDecl *Field = E->getInitializedFieldInUnion();
9813 Result = APValue(Field);
9814 if (!Field)
9815 return true;
9816
9817 // If the initializer list for a union does not contain any elements, the
9818 // first element of the union is value-initialized.
9819 // FIXME: The element should be initialized from an initializer list.
9820 // Is this difference ever observable for initializer lists which
9821 // we don't build?
9822 ImplicitValueInitExpr VIE(Field->getType());
9823 const Expr *InitExpr = E->getNumInits() ? E->getInit(0) : &VIE;
9824
9825 LValue Subobject = This;
9826 if (!HandleLValueMember(Info, InitExpr, Subobject, Field, &Layout))
9827 return false;
9828
9829 // Temporarily override This, in case there's a CXXDefaultInitExpr in here.
9830 ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This,
9831 isa<CXXDefaultInitExpr>(InitExpr));
9832
9833 if (EvaluateInPlace(Result.getUnionValue(), Info, Subobject, InitExpr)) {
9834 if (Field->isBitField())
9835 return truncateBitfieldValue(Info, InitExpr, Result.getUnionValue(),
9836 Field);
9837 return true;
9838 }
9839
9840 return false;
9841 }
9842
9843 if (!Result.hasValue())
9844 Result = APValue(APValue::UninitStruct(), CXXRD ? CXXRD->getNumBases() : 0,
9845 std::distance(RD->field_begin(), RD->field_end()));
9846 unsigned ElementNo = 0;
9847 bool Success = true;
9848
9849 // Initialize base classes.
9850 if (CXXRD && CXXRD->getNumBases()) {
9851 for (const auto &Base : CXXRD->bases()) {
9852 assert(ElementNo < E->getNumInits() && "missing init for base class")(static_cast <bool> (ElementNo < E->getNumInits()
&& "missing init for base class") ? void (0) : __assert_fail
("ElementNo < E->getNumInits() && \"missing init for base class\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9852, __extension__ __PRETTY_FUNCTION__))
;
9853 const Expr *Init = E->getInit(ElementNo);
9854
9855 LValue Subobject = This;
9856 if (!HandleLValueBase(Info, Init, Subobject, CXXRD, &Base))
9857 return false;
9858
9859 APValue &FieldVal = Result.getStructBase(ElementNo);
9860 if (!EvaluateInPlace(FieldVal, Info, Subobject, Init)) {
9861 if (!Info.noteFailure())
9862 return false;
9863 Success = false;
9864 }
9865 ++ElementNo;
9866 }
9867
9868 EvalObj.finishedConstructingBases();
9869 }
9870
9871 // Initialize members.
9872 for (const auto *Field : RD->fields()) {
9873 // Anonymous bit-fields are not considered members of the class for
9874 // purposes of aggregate initialization.
9875 if (Field->isUnnamedBitfield())
9876 continue;
9877
9878 LValue Subobject = This;
9879
9880 bool HaveInit = ElementNo < E->getNumInits();
9881
9882 // FIXME: Diagnostics here should point to the end of the initializer
9883 // list, not the start.
9884 if (!HandleLValueMember(Info, HaveInit ? E->getInit(ElementNo) : E,
9885 Subobject, Field, &Layout))
9886 return false;
9887
9888 // Perform an implicit value-initialization for members beyond the end of
9889 // the initializer list.
9890 ImplicitValueInitExpr VIE(HaveInit ? Info.Ctx.IntTy : Field->getType());
9891 const Expr *Init = HaveInit ? E->getInit(ElementNo++) : &VIE;
9892
9893 // Temporarily override This, in case there's a CXXDefaultInitExpr in here.
9894 ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This,
9895 isa<CXXDefaultInitExpr>(Init));
9896
9897 APValue &FieldVal = Result.getStructField(Field->getFieldIndex());
9898 if (!EvaluateInPlace(FieldVal, Info, Subobject, Init) ||
9899 (Field->isBitField() && !truncateBitfieldValue(Info, Init,
9900 FieldVal, Field))) {
9901 if (!Info.noteFailure())
9902 return false;
9903 Success = false;
9904 }
9905 }
9906
9907 EvalObj.finishedConstructingFields();
9908
9909 return Success;
9910}
9911
9912bool RecordExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E,
9913 QualType T) {
9914 // Note that E's type is not necessarily the type of our class here; we might
9915 // be initializing an array element instead.
9916 const CXXConstructorDecl *FD = E->getConstructor();
9917 if (FD->isInvalidDecl() || FD->getParent()->isInvalidDecl()) return false;
9918
9919 bool ZeroInit = E->requiresZeroInitialization();
9920 if (CheckTrivialDefaultConstructor(Info, E->getExprLoc(), FD, ZeroInit)) {
9921 // If we've already performed zero-initialization, we're already done.
9922 if (Result.hasValue())
9923 return true;
9924
9925 if (ZeroInit)
9926 return ZeroInitialization(E, T);
9927
9928 return getDefaultInitValue(T, Result);
9929 }
9930
9931 const FunctionDecl *Definition = nullptr;
9932 auto Body = FD->getBody(Definition);
9933
9934 if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body))
9935 return false;
9936
9937 // Avoid materializing a temporary for an elidable copy/move constructor.
9938 if (E->isElidable() && !ZeroInit) {
9939 // FIXME: This only handles the simplest case, where the source object
9940 // is passed directly as the first argument to the constructor.
9941 // This should also handle stepping though implicit casts and
9942 // and conversion sequences which involve two steps, with a
9943 // conversion operator followed by a converting constructor.
9944 const Expr *SrcObj = E->getArg(0);
9945 assert(SrcObj->isTemporaryObject(Info.Ctx, FD->getParent()))(static_cast <bool> (SrcObj->isTemporaryObject(Info.
Ctx, FD->getParent())) ? void (0) : __assert_fail ("SrcObj->isTemporaryObject(Info.Ctx, FD->getParent())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9945, __extension__ __PRETTY_FUNCTION__))
;
9946 assert(Info.Ctx.hasSameUnqualifiedType(E->getType(), SrcObj->getType()))(static_cast <bool> (Info.Ctx.hasSameUnqualifiedType(E->
getType(), SrcObj->getType())) ? void (0) : __assert_fail (
"Info.Ctx.hasSameUnqualifiedType(E->getType(), SrcObj->getType())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9946, __extension__ __PRETTY_FUNCTION__))
;
9947 if (const MaterializeTemporaryExpr *ME =
9948 dyn_cast<MaterializeTemporaryExpr>(SrcObj))
9949 return Visit(ME->getSubExpr());
9950 }
9951
9952 if (ZeroInit && !ZeroInitialization(E, T))
9953 return false;
9954
9955 auto Args = llvm::makeArrayRef(E->getArgs(), E->getNumArgs());
9956 return HandleConstructorCall(E, This, Args,
9957 cast<CXXConstructorDecl>(Definition), Info,
9958 Result);
9959}
9960
9961bool RecordExprEvaluator::VisitCXXInheritedCtorInitExpr(
9962 const CXXInheritedCtorInitExpr *E) {
9963 if (!Info.CurrentCall) {
9964 assert(Info.checkingPotentialConstantExpression())(static_cast <bool> (Info.checkingPotentialConstantExpression
()) ? void (0) : __assert_fail ("Info.checkingPotentialConstantExpression()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 9964, __extension__ __PRETTY_FUNCTION__))
;
9965 return false;
9966 }
9967
9968 const CXXConstructorDecl *FD = E->getConstructor();
9969 if (FD->isInvalidDecl() || FD->getParent()->isInvalidDecl())
9970 return false;
9971
9972 const FunctionDecl *Definition = nullptr;
9973 auto Body = FD->getBody(Definition);
9974
9975 if (!CheckConstexprFunction(Info, E->getExprLoc(), FD, Definition, Body))
9976 return false;
9977
9978 return HandleConstructorCall(E, This, Info.CurrentCall->Arguments,
9979 cast<CXXConstructorDecl>(Definition), Info,
9980 Result);
9981}
9982
9983bool RecordExprEvaluator::VisitCXXStdInitializerListExpr(
9984 const CXXStdInitializerListExpr *E) {
9985 const ConstantArrayType *ArrayType =
9986 Info.Ctx.getAsConstantArrayType(E->getSubExpr()->getType());
9987
9988 LValue Array;
9989 if (!EvaluateLValue(E->getSubExpr(), Array, Info))
9990 return false;
9991
9992 // Get a pointer to the first element of the array.
9993 Array.addArray(Info, E, ArrayType);
9994
9995 auto InvalidType = [&] {
9996 Info.FFDiag(E, diag::note_constexpr_unsupported_layout)
9997 << E->getType();
9998 return false;
9999 };
10000
10001 // FIXME: Perform the checks on the field types in SemaInit.
10002 RecordDecl *Record = E->getType()->castAs<RecordType>()->getDecl();
10003 RecordDecl::field_iterator Field = Record->field_begin();
10004 if (Field == Record->field_end())
10005 return InvalidType();
10006
10007 // Start pointer.
10008 if (!Field->getType()->isPointerType() ||
10009 !Info.Ctx.hasSameType(Field->getType()->getPointeeType(),
10010 ArrayType->getElementType()))
10011 return InvalidType();
10012
10013 // FIXME: What if the initializer_list type has base classes, etc?
10014 Result = APValue(APValue::UninitStruct(), 0, 2);
10015 Array.moveInto(Result.getStructField(0));
10016
10017 if (++Field == Record->field_end())
10018 return InvalidType();
10019
10020 if (Field->getType()->isPointerType() &&
10021 Info.Ctx.hasSameType(Field->getType()->getPointeeType(),
10022 ArrayType->getElementType())) {
10023 // End pointer.
10024 if (!HandleLValueArrayAdjustment(Info, E, Array,
10025 ArrayType->getElementType(),
10026 ArrayType->getSize().getZExtValue()))
10027 return false;
10028 Array.moveInto(Result.getStructField(1));
10029 } else if (Info.Ctx.hasSameType(Field->getType(), Info.Ctx.getSizeType()))
10030 // Length.
10031 Result.getStructField(1) = APValue(APSInt(ArrayType->getSize()));
10032 else
10033 return InvalidType();
10034
10035 if (++Field != Record->field_end())
10036 return InvalidType();
10037
10038 return true;
10039}
10040
10041bool RecordExprEvaluator::VisitLambdaExpr(const LambdaExpr *E) {
10042 const CXXRecordDecl *ClosureClass = E->getLambdaClass();
10043 if (ClosureClass->isInvalidDecl())
10044 return false;
10045
10046 const size_t NumFields =
10047 std::distance(ClosureClass->field_begin(), ClosureClass->field_end());
10048
10049 assert(NumFields == (size_t)std::distance(E->capture_init_begin(),(static_cast <bool> (NumFields == (size_t)std::distance
(E->capture_init_begin(), E->capture_init_end()) &&
"The number of lambda capture initializers should equal the number of "
"fields within the closure type") ? void (0) : __assert_fail
("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10052, __extension__ __PRETTY_FUNCTION__))
10050 E->capture_init_end()) &&(static_cast <bool> (NumFields == (size_t)std::distance
(E->capture_init_begin(), E->capture_init_end()) &&
"The number of lambda capture initializers should equal the number of "
"fields within the closure type") ? void (0) : __assert_fail
("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10052, __extension__ __PRETTY_FUNCTION__))
10051 "The number of lambda capture initializers should equal the number of "(static_cast <bool> (NumFields == (size_t)std::distance
(E->capture_init_begin(), E->capture_init_end()) &&
"The number of lambda capture initializers should equal the number of "
"fields within the closure type") ? void (0) : __assert_fail
("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10052, __extension__ __PRETTY_FUNCTION__))
10052 "fields within the closure type")(static_cast <bool> (NumFields == (size_t)std::distance
(E->capture_init_begin(), E->capture_init_end()) &&
"The number of lambda capture initializers should equal the number of "
"fields within the closure type") ? void (0) : __assert_fail
("NumFields == (size_t)std::distance(E->capture_init_begin(), E->capture_init_end()) && \"The number of lambda capture initializers should equal the number of \" \"fields within the closure type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10052, __extension__ __PRETTY_FUNCTION__))
;
10053
10054 Result = APValue(APValue::UninitStruct(), /*NumBases*/0, NumFields);
10055 // Iterate through all the lambda's closure object's fields and initialize
10056 // them.
10057 auto *CaptureInitIt = E->capture_init_begin();
10058 const LambdaCapture *CaptureIt = ClosureClass->captures_begin();
10059 bool Success = true;
10060 const ASTRecordLayout &Layout = Info.Ctx.getASTRecordLayout(ClosureClass);
10061 for (const auto *Field : ClosureClass->fields()) {
10062 assert(CaptureInitIt != E->capture_init_end())(static_cast <bool> (CaptureInitIt != E->capture_init_end
()) ? void (0) : __assert_fail ("CaptureInitIt != E->capture_init_end()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10062, __extension__ __PRETTY_FUNCTION__))
;
10063 // Get the initializer for this field
10064 Expr *const CurFieldInit = *CaptureInitIt++;
10065
10066 // If there is no initializer, either this is a VLA or an error has
10067 // occurred.
10068 if (!CurFieldInit)
10069 return Error(E);
10070
10071 LValue Subobject = This;
10072
10073 if (!HandleLValueMember(Info, E, Subobject, Field, &Layout))
10074 return false;
10075
10076 APValue &FieldVal = Result.getStructField(Field->getFieldIndex());
10077 if (!EvaluateInPlace(FieldVal, Info, Subobject, CurFieldInit)) {
10078 if (!Info.keepEvaluatingAfterFailure())
10079 return false;
10080 Success = false;
10081 }
10082 ++CaptureIt;
10083 }
10084 return Success;
10085}
10086
10087static bool EvaluateRecord(const Expr *E, const LValue &This,
10088 APValue &Result, EvalInfo &Info) {
10089 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10089, __extension__ __PRETTY_FUNCTION__))
;
10090 assert(E->isPRValue() && E->getType()->isRecordType() &&(static_cast <bool> (E->isPRValue() && E->
getType()->isRecordType() && "can't evaluate expression as a record rvalue"
) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isRecordType() && \"can't evaluate expression as a record rvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10091, __extension__ __PRETTY_FUNCTION__))
10091 "can't evaluate expression as a record rvalue")(static_cast <bool> (E->isPRValue() && E->
getType()->isRecordType() && "can't evaluate expression as a record rvalue"
) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isRecordType() && \"can't evaluate expression as a record rvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10091, __extension__ __PRETTY_FUNCTION__))
;
10092 return RecordExprEvaluator(Info, This, Result).Visit(E);
10093}
10094
10095//===----------------------------------------------------------------------===//
10096// Temporary Evaluation
10097//
10098// Temporaries are represented in the AST as rvalues, but generally behave like
10099// lvalues. The full-object of which the temporary is a subobject is implicitly
10100// materialized so that a reference can bind to it.
10101//===----------------------------------------------------------------------===//
10102namespace {
10103class TemporaryExprEvaluator
10104 : public LValueExprEvaluatorBase<TemporaryExprEvaluator> {
10105public:
10106 TemporaryExprEvaluator(EvalInfo &Info, LValue &Result) :
10107 LValueExprEvaluatorBaseTy(Info, Result, false) {}
10108
10109 /// Visit an expression which constructs the value of this temporary.
10110 bool VisitConstructExpr(const Expr *E) {
10111 APValue &Value = Info.CurrentCall->createTemporary(
10112 E, E->getType(), ScopeKind::FullExpression, Result);
10113 return EvaluateInPlace(Value, Info, Result, E);
10114 }
10115
10116 bool VisitCastExpr(const CastExpr *E) {
10117 switch (E->getCastKind()) {
10118 default:
10119 return LValueExprEvaluatorBaseTy::VisitCastExpr(E);
10120
10121 case CK_ConstructorConversion:
10122 return VisitConstructExpr(E->getSubExpr());
10123 }
10124 }
10125 bool VisitInitListExpr(const InitListExpr *E) {
10126 return VisitConstructExpr(E);
10127 }
10128 bool VisitCXXConstructExpr(const CXXConstructExpr *E) {
10129 return VisitConstructExpr(E);
10130 }
10131 bool VisitCallExpr(const CallExpr *E) {
10132 return VisitConstructExpr(E);
10133 }
10134 bool VisitCXXStdInitializerListExpr(const CXXStdInitializerListExpr *E) {
10135 return VisitConstructExpr(E);
10136 }
10137 bool VisitLambdaExpr(const LambdaExpr *E) {
10138 return VisitConstructExpr(E);
10139 }
10140};
10141} // end anonymous namespace
10142
10143/// Evaluate an expression of record type as a temporary.
10144static bool EvaluateTemporary(const Expr *E, LValue &Result, EvalInfo &Info) {
10145 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10145, __extension__ __PRETTY_FUNCTION__))
;
10146 assert(E->isPRValue() && E->getType()->isRecordType())(static_cast <bool> (E->isPRValue() && E->
getType()->isRecordType()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isRecordType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10146, __extension__ __PRETTY_FUNCTION__))
;
10147 return TemporaryExprEvaluator(Info, Result).Visit(E);
10148}
10149
10150//===----------------------------------------------------------------------===//
10151// Vector Evaluation
10152//===----------------------------------------------------------------------===//
10153
10154namespace {
10155 class VectorExprEvaluator
10156 : public ExprEvaluatorBase<VectorExprEvaluator> {
10157 APValue &Result;
10158 public:
10159
10160 VectorExprEvaluator(EvalInfo &info, APValue &Result)
10161 : ExprEvaluatorBaseTy(info), Result(Result) {}
10162
10163 bool Success(ArrayRef<APValue> V, const Expr *E) {
10164 assert(V.size() == E->getType()->castAs<VectorType>()->getNumElements())(static_cast <bool> (V.size() == E->getType()->castAs
<VectorType>()->getNumElements()) ? void (0) : __assert_fail
("V.size() == E->getType()->castAs<VectorType>()->getNumElements()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10164, __extension__ __PRETTY_FUNCTION__))
;
10165 // FIXME: remove this APValue copy.
10166 Result = APValue(V.data(), V.size());
10167 return true;
10168 }
10169 bool Success(const APValue &V, const Expr *E) {
10170 assert(V.isVector())(static_cast <bool> (V.isVector()) ? void (0) : __assert_fail
("V.isVector()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10170, __extension__ __PRETTY_FUNCTION__))
;
10171 Result = V;
10172 return true;
10173 }
10174 bool ZeroInitialization(const Expr *E);
10175
10176 bool VisitUnaryReal(const UnaryOperator *E)
10177 { return Visit(E->getSubExpr()); }
10178 bool VisitCastExpr(const CastExpr* E);
10179 bool VisitInitListExpr(const InitListExpr *E);
10180 bool VisitUnaryImag(const UnaryOperator *E);
10181 bool VisitBinaryOperator(const BinaryOperator *E);
10182 // FIXME: Missing: unary -, unary ~, conditional operator (for GNU
10183 // conditional select), shufflevector, ExtVectorElementExpr
10184 };
10185} // end anonymous namespace
10186
10187static bool EvaluateVector(const Expr* E, APValue& Result, EvalInfo &Info) {
10188 assert(E->isPRValue() && E->getType()->isVectorType() &&(static_cast <bool> (E->isPRValue() && E->
getType()->isVectorType() && "not a vector prvalue"
) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isVectorType() && \"not a vector prvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10189, __extension__ __PRETTY_FUNCTION__))
10189 "not a vector prvalue")(static_cast <bool> (E->isPRValue() && E->
getType()->isVectorType() && "not a vector prvalue"
) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isVectorType() && \"not a vector prvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10189, __extension__ __PRETTY_FUNCTION__))
;
10190 return VectorExprEvaluator(Info, Result).Visit(E);
10191}
10192
10193bool VectorExprEvaluator::VisitCastExpr(const CastExpr *E) {
10194 const VectorType *VTy = E->getType()->castAs<VectorType>();
10195 unsigned NElts = VTy->getNumElements();
10196
10197 const Expr *SE = E->getSubExpr();
10198 QualType SETy = SE->getType();
10199
10200 switch (E->getCastKind()) {
10201 case CK_VectorSplat: {
10202 APValue Val = APValue();
10203 if (SETy->isIntegerType()) {
10204 APSInt IntResult;
10205 if (!EvaluateInteger(SE, IntResult, Info))
10206 return false;
10207 Val = APValue(std::move(IntResult));
10208 } else if (SETy->isRealFloatingType()) {
10209 APFloat FloatResult(0.0);
10210 if (!EvaluateFloat(SE, FloatResult, Info))
10211 return false;
10212 Val = APValue(std::move(FloatResult));
10213 } else {
10214 return Error(E);
10215 }
10216
10217 // Splat and create vector APValue.
10218 SmallVector<APValue, 4> Elts(NElts, Val);
10219 return Success(Elts, E);
10220 }
10221 case CK_BitCast: {
10222 // Evaluate the operand into an APInt we can extract from.
10223 llvm::APInt SValInt;
10224 if (!EvalAndBitcastToAPInt(Info, SE, SValInt))
10225 return false;
10226 // Extract the elements
10227 QualType EltTy = VTy->getElementType();
10228 unsigned EltSize = Info.Ctx.getTypeSize(EltTy);
10229 bool BigEndian = Info.Ctx.getTargetInfo().isBigEndian();
10230 SmallVector<APValue, 4> Elts;
10231 if (EltTy->isRealFloatingType()) {
10232 const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(EltTy);
10233 unsigned FloatEltSize = EltSize;
10234 if (&Sem == &APFloat::x87DoubleExtended())
10235 FloatEltSize = 80;
10236 for (unsigned i = 0; i < NElts; i++) {
10237 llvm::APInt Elt;
10238 if (BigEndian)
10239 Elt = SValInt.rotl(i*EltSize+FloatEltSize).trunc(FloatEltSize);
10240 else
10241 Elt = SValInt.rotr(i*EltSize).trunc(FloatEltSize);
10242 Elts.push_back(APValue(APFloat(Sem, Elt)));
10243 }
10244 } else if (EltTy->isIntegerType()) {
10245 for (unsigned i = 0; i < NElts; i++) {
10246 llvm::APInt Elt;
10247 if (BigEndian)
10248 Elt = SValInt.rotl(i*EltSize+EltSize).zextOrTrunc(EltSize);
10249 else
10250 Elt = SValInt.rotr(i*EltSize).zextOrTrunc(EltSize);
10251 Elts.push_back(APValue(APSInt(Elt, !EltTy->isSignedIntegerType())));
10252 }
10253 } else {
10254 return Error(E);
10255 }
10256 return Success(Elts, E);
10257 }
10258 default:
10259 return ExprEvaluatorBaseTy::VisitCastExpr(E);
10260 }
10261}
10262
10263bool
10264VectorExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
10265 const VectorType *VT = E->getType()->castAs<VectorType>();
10266 unsigned NumInits = E->getNumInits();
10267 unsigned NumElements = VT->getNumElements();
10268
10269 QualType EltTy = VT->getElementType();
10270 SmallVector<APValue, 4> Elements;
10271
10272 // The number of initializers can be less than the number of
10273 // vector elements. For OpenCL, this can be due to nested vector
10274 // initialization. For GCC compatibility, missing trailing elements
10275 // should be initialized with zeroes.
10276 unsigned CountInits = 0, CountElts = 0;
10277 while (CountElts < NumElements) {
10278 // Handle nested vector initialization.
10279 if (CountInits < NumInits
10280 && E->getInit(CountInits)->getType()->isVectorType()) {
10281 APValue v;
10282 if (!EvaluateVector(E->getInit(CountInits), v, Info))
10283 return Error(E);
10284 unsigned vlen = v.getVectorLength();
10285 for (unsigned j = 0; j < vlen; j++)
10286 Elements.push_back(v.getVectorElt(j));
10287 CountElts += vlen;
10288 } else if (EltTy->isIntegerType()) {
10289 llvm::APSInt sInt(32);
10290 if (CountInits < NumInits) {
10291 if (!EvaluateInteger(E->getInit(CountInits), sInt, Info))
10292 return false;
10293 } else // trailing integer zero.
10294 sInt = Info.Ctx.MakeIntValue(0, EltTy);
10295 Elements.push_back(APValue(sInt));
10296 CountElts++;
10297 } else {
10298 llvm::APFloat f(0.0);
10299 if (CountInits < NumInits) {
10300 if (!EvaluateFloat(E->getInit(CountInits), f, Info))
10301 return false;
10302 } else // trailing float zero.
10303 f = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy));
10304 Elements.push_back(APValue(f));
10305 CountElts++;
10306 }
10307 CountInits++;
10308 }
10309 return Success(Elements, E);
10310}
10311
10312bool
10313VectorExprEvaluator::ZeroInitialization(const Expr *E) {
10314 const auto *VT = E->getType()->castAs<VectorType>();
10315 QualType EltTy = VT->getElementType();
10316 APValue ZeroElement;
10317 if (EltTy->isIntegerType())
10318 ZeroElement = APValue(Info.Ctx.MakeIntValue(0, EltTy));
10319 else
10320 ZeroElement =
10321 APValue(APFloat::getZero(Info.Ctx.getFloatTypeSemantics(EltTy)));
10322
10323 SmallVector<APValue, 4> Elements(VT->getNumElements(), ZeroElement);
10324 return Success(Elements, E);
10325}
10326
10327bool VectorExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
10328 VisitIgnoredValue(E->getSubExpr());
10329 return ZeroInitialization(E);
10330}
10331
10332bool VectorExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
10333 BinaryOperatorKind Op = E->getOpcode();
10334 assert(Op != BO_PtrMemD && Op != BO_PtrMemI && Op != BO_Cmp &&(static_cast <bool> (Op != BO_PtrMemD && Op != BO_PtrMemI
&& Op != BO_Cmp && "Operation not supported on vector types"
) ? void (0) : __assert_fail ("Op != BO_PtrMemD && Op != BO_PtrMemI && Op != BO_Cmp && \"Operation not supported on vector types\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10335, __extension__ __PRETTY_FUNCTION__))
10335 "Operation not supported on vector types")(static_cast <bool> (Op != BO_PtrMemD && Op != BO_PtrMemI
&& Op != BO_Cmp && "Operation not supported on vector types"
) ? void (0) : __assert_fail ("Op != BO_PtrMemD && Op != BO_PtrMemI && Op != BO_Cmp && \"Operation not supported on vector types\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10335, __extension__ __PRETTY_FUNCTION__))
;
10336
10337 if (Op == BO_Comma)
10338 return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
10339
10340 Expr *LHS = E->getLHS();
10341 Expr *RHS = E->getRHS();
10342
10343 assert(LHS->getType()->isVectorType() && RHS->getType()->isVectorType() &&(static_cast <bool> (LHS->getType()->isVectorType
() && RHS->getType()->isVectorType() &&
"Must both be vector types") ? void (0) : __assert_fail ("LHS->getType()->isVectorType() && RHS->getType()->isVectorType() && \"Must both be vector types\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10344, __extension__ __PRETTY_FUNCTION__))
10344 "Must both be vector types")(static_cast <bool> (LHS->getType()->isVectorType
() && RHS->getType()->isVectorType() &&
"Must both be vector types") ? void (0) : __assert_fail ("LHS->getType()->isVectorType() && RHS->getType()->isVectorType() && \"Must both be vector types\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10344, __extension__ __PRETTY_FUNCTION__))
;
10345 // Checking JUST the types are the same would be fine, except shifts don't
10346 // need to have their types be the same (since you always shift by an int).
10347 assert(LHS->getType()->castAs<VectorType>()->getNumElements() ==(static_cast <bool> (LHS->getType()->castAs<VectorType
>()->getNumElements() == E->getType()->castAs<
VectorType>()->getNumElements() && RHS->getType
()->castAs<VectorType>()->getNumElements() == E->
getType()->castAs<VectorType>()->getNumElements()
&& "All operands must be the same size.") ? void (0)
: __assert_fail ("LHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && RHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && \"All operands must be the same size.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10351, __extension__ __PRETTY_FUNCTION__))
10348 E->getType()->castAs<VectorType>()->getNumElements() &&(static_cast <bool> (LHS->getType()->castAs<VectorType
>()->getNumElements() == E->getType()->castAs<
VectorType>()->getNumElements() && RHS->getType
()->castAs<VectorType>()->getNumElements() == E->
getType()->castAs<VectorType>()->getNumElements()
&& "All operands must be the same size.") ? void (0)
: __assert_fail ("LHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && RHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && \"All operands must be the same size.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10351, __extension__ __PRETTY_FUNCTION__))
10349 RHS->getType()->castAs<VectorType>()->getNumElements() ==(static_cast <bool> (LHS->getType()->castAs<VectorType
>()->getNumElements() == E->getType()->castAs<
VectorType>()->getNumElements() && RHS->getType
()->castAs<VectorType>()->getNumElements() == E->
getType()->castAs<VectorType>()->getNumElements()
&& "All operands must be the same size.") ? void (0)
: __assert_fail ("LHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && RHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && \"All operands must be the same size.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10351, __extension__ __PRETTY_FUNCTION__))
10350 E->getType()->castAs<VectorType>()->getNumElements() &&(static_cast <bool> (LHS->getType()->castAs<VectorType
>()->getNumElements() == E->getType()->castAs<
VectorType>()->getNumElements() && RHS->getType
()->castAs<VectorType>()->getNumElements() == E->
getType()->castAs<VectorType>()->getNumElements()
&& "All operands must be the same size.") ? void (0)
: __assert_fail ("LHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && RHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && \"All operands must be the same size.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10351, __extension__ __PRETTY_FUNCTION__))
10351 "All operands must be the same size.")(static_cast <bool> (LHS->getType()->castAs<VectorType
>()->getNumElements() == E->getType()->castAs<
VectorType>()->getNumElements() && RHS->getType
()->castAs<VectorType>()->getNumElements() == E->
getType()->castAs<VectorType>()->getNumElements()
&& "All operands must be the same size.") ? void (0)
: __assert_fail ("LHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && RHS->getType()->castAs<VectorType>()->getNumElements() == E->getType()->castAs<VectorType>()->getNumElements() && \"All operands must be the same size.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10351, __extension__ __PRETTY_FUNCTION__))
;
10352
10353 APValue LHSValue;
10354 APValue RHSValue;
10355 bool LHSOK = Evaluate(LHSValue, Info, LHS);
10356 if (!LHSOK && !Info.noteFailure())
10357 return false;
10358 if (!Evaluate(RHSValue, Info, RHS) || !LHSOK)
10359 return false;
10360
10361 if (!handleVectorVectorBinOp(Info, E, Op, LHSValue, RHSValue))
10362 return false;
10363
10364 return Success(LHSValue, E);
10365}
10366
10367//===----------------------------------------------------------------------===//
10368// Array Evaluation
10369//===----------------------------------------------------------------------===//
10370
10371namespace {
10372 class ArrayExprEvaluator
10373 : public ExprEvaluatorBase<ArrayExprEvaluator> {
10374 const LValue &This;
10375 APValue &Result;
10376 public:
10377
10378 ArrayExprEvaluator(EvalInfo &Info, const LValue &This, APValue &Result)
10379 : ExprEvaluatorBaseTy(Info), This(This), Result(Result) {}
10380
10381 bool Success(const APValue &V, const Expr *E) {
10382 assert(V.isArray() && "expected array")(static_cast <bool> (V.isArray() && "expected array"
) ? void (0) : __assert_fail ("V.isArray() && \"expected array\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10382, __extension__ __PRETTY_FUNCTION__))
;
10383 Result = V;
10384 return true;
10385 }
10386
10387 bool ZeroInitialization(const Expr *E) {
10388 const ConstantArrayType *CAT =
10389 Info.Ctx.getAsConstantArrayType(E->getType());
10390 if (!CAT) {
10391 if (E->getType()->isIncompleteArrayType()) {
10392 // We can be asked to zero-initialize a flexible array member; this
10393 // is represented as an ImplicitValueInitExpr of incomplete array
10394 // type. In this case, the array has zero elements.
10395 Result = APValue(APValue::UninitArray(), 0, 0);
10396 return true;
10397 }
10398 // FIXME: We could handle VLAs here.
10399 return Error(E);
10400 }
10401
10402 Result = APValue(APValue::UninitArray(), 0,
10403 CAT->getSize().getZExtValue());
10404 if (!Result.hasArrayFiller())
10405 return true;
10406
10407 // Zero-initialize all elements.
10408 LValue Subobject = This;
10409 Subobject.addArray(Info, E, CAT);
10410 ImplicitValueInitExpr VIE(CAT->getElementType());
10411 return EvaluateInPlace(Result.getArrayFiller(), Info, Subobject, &VIE);
10412 }
10413
10414 bool VisitCallExpr(const CallExpr *E) {
10415 return handleCallExpr(E, Result, &This);
10416 }
10417 bool VisitInitListExpr(const InitListExpr *E,
10418 QualType AllocType = QualType());
10419 bool VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E);
10420 bool VisitCXXConstructExpr(const CXXConstructExpr *E);
10421 bool VisitCXXConstructExpr(const CXXConstructExpr *E,
10422 const LValue &Subobject,
10423 APValue *Value, QualType Type);
10424 bool VisitStringLiteral(const StringLiteral *E,
10425 QualType AllocType = QualType()) {
10426 expandStringLiteral(Info, E, Result, AllocType);
10427 return true;
10428 }
10429 };
10430} // end anonymous namespace
10431
10432static bool EvaluateArray(const Expr *E, const LValue &This,
10433 APValue &Result, EvalInfo &Info) {
10434 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10434, __extension__ __PRETTY_FUNCTION__))
;
10435 assert(E->isPRValue() && E->getType()->isArrayType() &&(static_cast <bool> (E->isPRValue() && E->
getType()->isArrayType() && "not an array prvalue"
) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isArrayType() && \"not an array prvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10436, __extension__ __PRETTY_FUNCTION__))
10436 "not an array prvalue")(static_cast <bool> (E->isPRValue() && E->
getType()->isArrayType() && "not an array prvalue"
) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isArrayType() && \"not an array prvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10436, __extension__ __PRETTY_FUNCTION__))
;
10437 return ArrayExprEvaluator(Info, This, Result).Visit(E);
10438}
10439
10440static bool EvaluateArrayNewInitList(EvalInfo &Info, LValue &This,
10441 APValue &Result, const InitListExpr *ILE,
10442 QualType AllocType) {
10443 assert(!ILE->isValueDependent())(static_cast <bool> (!ILE->isValueDependent()) ? void
(0) : __assert_fail ("!ILE->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10443, __extension__ __PRETTY_FUNCTION__))
;
1
Assuming the condition is true
2
'?' condition is true
10444 assert(ILE->isPRValue() && ILE->getType()->isArrayType() &&(static_cast <bool> (ILE->isPRValue() && ILE
->getType()->isArrayType() && "not an array prvalue"
) ? void (0) : __assert_fail ("ILE->isPRValue() && ILE->getType()->isArrayType() && \"not an array prvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10445, __extension__ __PRETTY_FUNCTION__))
3
'?' condition is true
10445 "not an array prvalue")(static_cast <bool> (ILE->isPRValue() && ILE
->getType()->isArrayType() && "not an array prvalue"
) ? void (0) : __assert_fail ("ILE->isPRValue() && ILE->getType()->isArrayType() && \"not an array prvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10445, __extension__ __PRETTY_FUNCTION__))
;
10446 return ArrayExprEvaluator(Info, This, Result)
4
Calling 'ArrayExprEvaluator::VisitInitListExpr'
10447 .VisitInitListExpr(ILE, AllocType);
10448}
10449
10450static bool EvaluateArrayNewConstructExpr(EvalInfo &Info, LValue &This,
10451 APValue &Result,
10452 const CXXConstructExpr *CCE,
10453 QualType AllocType) {
10454 assert(!CCE->isValueDependent())(static_cast <bool> (!CCE->isValueDependent()) ? void
(0) : __assert_fail ("!CCE->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10454, __extension__ __PRETTY_FUNCTION__))
;
10455 assert(CCE->isPRValue() && CCE->getType()->isArrayType() &&(static_cast <bool> (CCE->isPRValue() && CCE
->getType()->isArrayType() && "not an array prvalue"
) ? void (0) : __assert_fail ("CCE->isPRValue() && CCE->getType()->isArrayType() && \"not an array prvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10456, __extension__ __PRETTY_FUNCTION__))
10456 "not an array prvalue")(static_cast <bool> (CCE->isPRValue() && CCE
->getType()->isArrayType() && "not an array prvalue"
) ? void (0) : __assert_fail ("CCE->isPRValue() && CCE->getType()->isArrayType() && \"not an array prvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10456, __extension__ __PRETTY_FUNCTION__))
;
10457 return ArrayExprEvaluator(Info, This, Result)
10458 .VisitCXXConstructExpr(CCE, This, &Result, AllocType);
10459}
10460
10461// Return true iff the given array filler may depend on the element index.
10462static bool MaybeElementDependentArrayFiller(const Expr *FillerExpr) {
10463 // For now, just allow non-class value-initialization and initialization
10464 // lists comprised of them.
10465 if (isa<ImplicitValueInitExpr>(FillerExpr))
10466 return false;
10467 if (const InitListExpr *ILE = dyn_cast<InitListExpr>(FillerExpr)) {
10468 for (unsigned I = 0, E = ILE->getNumInits(); I != E; ++I) {
10469 if (MaybeElementDependentArrayFiller(ILE->getInit(I)))
10470 return true;
10471 }
10472 return false;
10473 }
10474 return true;
10475}
10476
10477bool ArrayExprEvaluator::VisitInitListExpr(const InitListExpr *E,
10478 QualType AllocType) {
10479 const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(
10480 AllocType.isNull() ? E->getType() : AllocType);
5
'?' condition is false
10481 if (!CAT
5.1
'CAT' is non-null
)
6
Taking false branch
10482 return Error(E);
10483
10484 // C++11 [dcl.init.string]p1: A char array [...] can be initialized by [...]
10485 // an appropriately-typed string literal enclosed in braces.
10486 if (E->isStringLiteralInit()) {
7
Assuming the condition is false
10487 auto *SL = dyn_cast<StringLiteral>(E->getInit(0)->IgnoreParenImpCasts());
10488 // FIXME: Support ObjCEncodeExpr here once we support it in
10489 // ArrayExprEvaluator generally.
10490 if (!SL)
10491 return Error(E);
10492 return VisitStringLiteral(SL, AllocType);
10493 }
10494 // Any other transparent list init will need proper handling of the
10495 // AllocType; we can't just recurse to the inner initializer.
10496 assert(!E->isTransparent() &&(static_cast <bool> (!E->isTransparent() && "transparent array list initialization is not string literal init?"
) ? void (0) : __assert_fail ("!E->isTransparent() && \"transparent array list initialization is not string literal init?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10497, __extension__ __PRETTY_FUNCTION__))
8
Taking false branch
9
Assuming the condition is true
10
'?' condition is true
10497 "transparent array list initialization is not string literal init?")(static_cast <bool> (!E->isTransparent() && "transparent array list initialization is not string literal init?"
) ? void (0) : __assert_fail ("!E->isTransparent() && \"transparent array list initialization is not string literal init?\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10497, __extension__ __PRETTY_FUNCTION__))
;
10498
10499 bool Success = true;
10500
10501 assert((!Result.isArray() || Result.getArrayInitializedElts() == 0) &&(static_cast <bool> ((!Result.isArray() || Result.getArrayInitializedElts
() == 0) && "zero-initialized array shouldn't have any initialized elts"
) ? void (0) : __assert_fail ("(!Result.isArray() || Result.getArrayInitializedElts() == 0) && \"zero-initialized array shouldn't have any initialized elts\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10502, __extension__ __PRETTY_FUNCTION__))
11
'?' condition is true
10502 "zero-initialized array shouldn't have any initialized elts")(static_cast <bool> ((!Result.isArray() || Result.getArrayInitializedElts
() == 0) && "zero-initialized array shouldn't have any initialized elts"
) ? void (0) : __assert_fail ("(!Result.isArray() || Result.getArrayInitializedElts() == 0) && \"zero-initialized array shouldn't have any initialized elts\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10502, __extension__ __PRETTY_FUNCTION__))
;
10503 APValue Filler;
10504 if (Result.isArray() && Result.hasArrayFiller())
10505 Filler = Result.getArrayFiller();
10506
10507 unsigned NumEltsToInit = E->getNumInits();
10508 unsigned NumElts = CAT->getSize().getZExtValue();
10509 const Expr *FillerExpr = E->hasArrayFiller() ? E->getArrayFiller() : nullptr;
12
Assuming the condition is false
13
'?' condition is false
14
'FillerExpr' initialized to a null pointer value
10510
10511 // If the initializer might depend on the array index, run it for each
10512 // array element.
10513 if (NumEltsToInit != NumElts && MaybeElementDependentArrayFiller(FillerExpr))
15
Assuming 'NumEltsToInit' is equal to 'NumElts'
10514 NumEltsToInit = NumElts;
10515
10516 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)
16
Assuming 'DebugFlag' is false
17
Loop condition is false. Exiting loop
10517 << NumEltsToInit << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("exprconstant")) { llvm::dbgs() << "The number of elements to initialize: "
<< NumEltsToInit << ".\n"; } } while (false)
;
10518
10519 Result = APValue(APValue::UninitArray(), NumEltsToInit, NumElts);
10520
10521 // If the array was previously zero-initialized, preserve the
10522 // zero-initialized values.
10523 if (Filler.hasValue()) {
18
Taking false branch
10524 for (unsigned I = 0, E = Result.getArrayInitializedElts(); I != E; ++I)
10525 Result.getArrayInitializedElt(I) = Filler;
10526 if (Result.hasArrayFiller())
10527 Result.getArrayFiller() = Filler;
10528 }
10529
10530 LValue Subobject = This;
10531 Subobject.addArray(Info, E, CAT);
10532 for (unsigned Index = 0; Index != NumEltsToInit; ++Index) {
19
Assuming 'Index' is not equal to 'NumEltsToInit'
10533 const Expr *Init =
20
Loop condition is true. Entering loop body
23
'Init' initialized to a null pointer value
10534 Index < E->getNumInits() ? E->getInit(Index) : FillerExpr;
21
Assuming the condition is false
22
'?' condition is false
10535 if (!EvaluateInPlace(Result.getArrayInitializedElt(Index),
24
Assuming the condition is false
10536 Info, Subobject, Init) ||
10537 !HandleLValueArrayAdjustment(Info, Init, Subobject,
25
Passing null pointer value via 2nd parameter 'E'
26
Calling 'HandleLValueArrayAdjustment'
10538 CAT->getElementType(), 1)) {
10539 if (!Info.noteFailure())
10540 return false;
10541 Success = false;
10542 }
10543 }
10544
10545 if (!Result.hasArrayFiller())
10546 return Success;
10547
10548 // If we get here, we have a trivial filler, which we can just evaluate
10549 // once and splat over the rest of the array elements.
10550 assert(FillerExpr && "no array filler for incomplete init list")(static_cast <bool> (FillerExpr && "no array filler for incomplete init list"
) ? void (0) : __assert_fail ("FillerExpr && \"no array filler for incomplete init list\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10550, __extension__ __PRETTY_FUNCTION__))
;
10551 return EvaluateInPlace(Result.getArrayFiller(), Info, Subobject,
10552 FillerExpr) && Success;
10553}
10554
10555bool ArrayExprEvaluator::VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E) {
10556 LValue CommonLV;
10557 if (E->getCommonExpr() &&
10558 !Evaluate(Info.CurrentCall->createTemporary(
10559 E->getCommonExpr(),
10560 getStorageType(Info.Ctx, E->getCommonExpr()),
10561 ScopeKind::FullExpression, CommonLV),
10562 Info, E->getCommonExpr()->getSourceExpr()))
10563 return false;
10564
10565 auto *CAT = cast<ConstantArrayType>(E->getType()->castAsArrayTypeUnsafe());
10566
10567 uint64_t Elements = CAT->getSize().getZExtValue();
10568 Result = APValue(APValue::UninitArray(), Elements, Elements);
10569
10570 LValue Subobject = This;
10571 Subobject.addArray(Info, E, CAT);
10572
10573 bool Success = true;
10574 for (EvalInfo::ArrayInitLoopIndex Index(Info); Index != Elements; ++Index) {
10575 if (!EvaluateInPlace(Result.getArrayInitializedElt(Index),
10576 Info, Subobject, E->getSubExpr()) ||
10577 !HandleLValueArrayAdjustment(Info, E, Subobject,
10578 CAT->getElementType(), 1)) {
10579 if (!Info.noteFailure())
10580 return false;
10581 Success = false;
10582 }
10583 }
10584
10585 return Success;
10586}
10587
10588bool ArrayExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E) {
10589 return VisitCXXConstructExpr(E, This, &Result, E->getType());
10590}
10591
10592bool ArrayExprEvaluator::VisitCXXConstructExpr(const CXXConstructExpr *E,
10593 const LValue &Subobject,
10594 APValue *Value,
10595 QualType Type) {
10596 bool HadZeroInit = Value->hasValue();
10597
10598 if (const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(Type)) {
10599 unsigned N = CAT->getSize().getZExtValue();
10600
10601 // Preserve the array filler if we had prior zero-initialization.
10602 APValue Filler =
10603 HadZeroInit && Value->hasArrayFiller() ? Value->getArrayFiller()
10604 : APValue();
10605
10606 *Value = APValue(APValue::UninitArray(), N, N);
10607
10608 if (HadZeroInit)
10609 for (unsigned I = 0; I != N; ++I)
10610 Value->getArrayInitializedElt(I) = Filler;
10611
10612 // Initialize the elements.
10613 LValue ArrayElt = Subobject;
10614 ArrayElt.addArray(Info, E, CAT);
10615 for (unsigned I = 0; I != N; ++I)
10616 if (!VisitCXXConstructExpr(E, ArrayElt, &Value->getArrayInitializedElt(I),
10617 CAT->getElementType()) ||
10618 !HandleLValueArrayAdjustment(Info, E, ArrayElt,
10619 CAT->getElementType(), 1))
10620 return false;
10621
10622 return true;
10623 }
10624
10625 if (!Type->isRecordType())
10626 return Error(E);
10627
10628 return RecordExprEvaluator(Info, Subobject, *Value)
10629 .VisitCXXConstructExpr(E, Type);
10630}
10631
10632//===----------------------------------------------------------------------===//
10633// Integer Evaluation
10634//
10635// As a GNU extension, we support casting pointers to sufficiently-wide integer
10636// types and back in constant folding. Integer values are thus represented
10637// either as an integer-valued APValue, or as an lvalue-valued APValue.
10638//===----------------------------------------------------------------------===//
10639
10640namespace {
10641class IntExprEvaluator
10642 : public ExprEvaluatorBase<IntExprEvaluator> {
10643 APValue &Result;
10644public:
10645 IntExprEvaluator(EvalInfo &info, APValue &result)
10646 : ExprEvaluatorBaseTy(info), Result(result) {}
10647
10648 bool Success(const llvm::APSInt &SI, const Expr *E, APValue &Result) {
10649 assert(E->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10650, __extension__ __PRETTY_FUNCTION__))
10650 "Invalid evaluation result.")(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10650, __extension__ __PRETTY_FUNCTION__))
;
10651 assert(SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() &&(static_cast <bool> (SI.isSigned() == E->getType()->
isSignedIntegerOrEnumerationType() && "Invalid evaluation result."
) ? void (0) : __assert_fail ("SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10652, __extension__ __PRETTY_FUNCTION__))
10652 "Invalid evaluation result.")(static_cast <bool> (SI.isSigned() == E->getType()->
isSignedIntegerOrEnumerationType() && "Invalid evaluation result."
) ? void (0) : __assert_fail ("SI.isSigned() == E->getType()->isSignedIntegerOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10652, __extension__ __PRETTY_FUNCTION__))
;
10653 assert(SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&(static_cast <bool> (SI.getBitWidth() == Info.Ctx.getIntWidth
(E->getType()) && "Invalid evaluation result.") ? void
(0) : __assert_fail ("SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10654, __extension__ __PRETTY_FUNCTION__))
10654 "Invalid evaluation result.")(static_cast <bool> (SI.getBitWidth() == Info.Ctx.getIntWidth
(E->getType()) && "Invalid evaluation result.") ? void
(0) : __assert_fail ("SI.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10654, __extension__ __PRETTY_FUNCTION__))
;
10655 Result = APValue(SI);
10656 return true;
10657 }
10658 bool Success(const llvm::APSInt &SI, const Expr *E) {
10659 return Success(SI, E, Result);
10660 }
10661
10662 bool Success(const llvm::APInt &I, const Expr *E, APValue &Result) {
10663 assert(E->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10664, __extension__ __PRETTY_FUNCTION__))
10664 "Invalid evaluation result.")(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10664, __extension__ __PRETTY_FUNCTION__))
;
10665 assert(I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) &&(static_cast <bool> (I.getBitWidth() == Info.Ctx.getIntWidth
(E->getType()) && "Invalid evaluation result.") ? void
(0) : __assert_fail ("I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10666, __extension__ __PRETTY_FUNCTION__))
10666 "Invalid evaluation result.")(static_cast <bool> (I.getBitWidth() == Info.Ctx.getIntWidth
(E->getType()) && "Invalid evaluation result.") ? void
(0) : __assert_fail ("I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10666, __extension__ __PRETTY_FUNCTION__))
;
10667 Result = APValue(APSInt(I));
10668 Result.getInt().setIsUnsigned(
10669 E->getType()->isUnsignedIntegerOrEnumerationType());
10670 return true;
10671 }
10672 bool Success(const llvm::APInt &I, const Expr *E) {
10673 return Success(I, E, Result);
10674 }
10675
10676 bool Success(uint64_t Value, const Expr *E, APValue &Result) {
10677 assert(E->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10678, __extension__ __PRETTY_FUNCTION__))
10678 "Invalid evaluation result.")(static_cast <bool> (E->getType()->isIntegralOrEnumerationType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
("E->getType()->isIntegralOrEnumerationType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10678, __extension__ __PRETTY_FUNCTION__))
;
10679 Result = APValue(Info.Ctx.MakeIntValue(Value, E->getType()));
10680 return true;
10681 }
10682 bool Success(uint64_t Value, const Expr *E) {
10683 return Success(Value, E, Result);
10684 }
10685
10686 bool Success(CharUnits Size, const Expr *E) {
10687 return Success(Size.getQuantity(), E);
10688 }
10689
10690 bool Success(const APValue &V, const Expr *E) {
10691 if (V.isLValue() || V.isAddrLabelDiff() || V.isIndeterminate()) {
10692 Result = V;
10693 return true;
10694 }
10695 return Success(V.getInt(), E);
10696 }
10697
10698 bool ZeroInitialization(const Expr *E) { return Success(0, E); }
10699
10700 //===--------------------------------------------------------------------===//
10701 // Visitor Methods
10702 //===--------------------------------------------------------------------===//
10703
10704 bool VisitIntegerLiteral(const IntegerLiteral *E) {
10705 return Success(E->getValue(), E);
10706 }
10707 bool VisitCharacterLiteral(const CharacterLiteral *E) {
10708 return Success(E->getValue(), E);
10709 }
10710
10711 bool CheckReferencedDecl(const Expr *E, const Decl *D);
10712 bool VisitDeclRefExpr(const DeclRefExpr *E) {
10713 if (CheckReferencedDecl(E, E->getDecl()))
10714 return true;
10715
10716 return ExprEvaluatorBaseTy::VisitDeclRefExpr(E);
10717 }
10718 bool VisitMemberExpr(const MemberExpr *E) {
10719 if (CheckReferencedDecl(E, E->getMemberDecl())) {
10720 VisitIgnoredBaseExpression(E->getBase());
10721 return true;
10722 }
10723
10724 return ExprEvaluatorBaseTy::VisitMemberExpr(E);
10725 }
10726
10727 bool VisitCallExpr(const CallExpr *E);
10728 bool VisitBuiltinCallExpr(const CallExpr *E, unsigned BuiltinOp);
10729 bool VisitBinaryOperator(const BinaryOperator *E);
10730 bool VisitOffsetOfExpr(const OffsetOfExpr *E);
10731 bool VisitUnaryOperator(const UnaryOperator *E);
10732
10733 bool VisitCastExpr(const CastExpr* E);
10734 bool VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E);
10735
10736 bool VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) {
10737 return Success(E->getValue(), E);
10738 }
10739
10740 bool VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *E) {
10741 return Success(E->getValue(), E);
10742 }
10743
10744 bool VisitArrayInitIndexExpr(const ArrayInitIndexExpr *E) {
10745 if (Info.ArrayInitIndex == uint64_t(-1)) {
10746 // We were asked to evaluate this subexpression independent of the
10747 // enclosing ArrayInitLoopExpr. We can't do that.
10748 Info.FFDiag(E);
10749 return false;
10750 }
10751 return Success(Info.ArrayInitIndex, E);
10752 }
10753
10754 // Note, GNU defines __null as an integer, not a pointer.
10755 bool VisitGNUNullExpr(const GNUNullExpr *E) {
10756 return ZeroInitialization(E);
10757 }
10758
10759 bool VisitTypeTraitExpr(const TypeTraitExpr *E) {
10760 return Success(E->getValue(), E);
10761 }
10762
10763 bool VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) {
10764 return Success(E->getValue(), E);
10765 }
10766
10767 bool VisitExpressionTraitExpr(const ExpressionTraitExpr *E) {
10768 return Success(E->getValue(), E);
10769 }
10770
10771 bool VisitUnaryReal(const UnaryOperator *E);
10772 bool VisitUnaryImag(const UnaryOperator *E);
10773
10774 bool VisitCXXNoexceptExpr(const CXXNoexceptExpr *E);
10775 bool VisitSizeOfPackExpr(const SizeOfPackExpr *E);
10776 bool VisitSourceLocExpr(const SourceLocExpr *E);
10777 bool VisitConceptSpecializationExpr(const ConceptSpecializationExpr *E);
10778 bool VisitRequiresExpr(const RequiresExpr *E);
10779 // FIXME: Missing: array subscript of vector, member of vector
10780};
10781
10782class FixedPointExprEvaluator
10783 : public ExprEvaluatorBase<FixedPointExprEvaluator> {
10784 APValue &Result;
10785
10786 public:
10787 FixedPointExprEvaluator(EvalInfo &info, APValue &result)
10788 : ExprEvaluatorBaseTy(info), Result(result) {}
10789
10790 bool Success(const llvm::APInt &I, const Expr *E) {
10791 return Success(
10792 APFixedPoint(I, Info.Ctx.getFixedPointSemantics(E->getType())), E);
10793 }
10794
10795 bool Success(uint64_t Value, const Expr *E) {
10796 return Success(
10797 APFixedPoint(Value, Info.Ctx.getFixedPointSemantics(E->getType())), E);
10798 }
10799
10800 bool Success(const APValue &V, const Expr *E) {
10801 return Success(V.getFixedPoint(), E);
10802 }
10803
10804 bool Success(const APFixedPoint &V, const Expr *E) {
10805 assert(E->getType()->isFixedPointType() && "Invalid evaluation result.")(static_cast <bool> (E->getType()->isFixedPointType
() && "Invalid evaluation result.") ? void (0) : __assert_fail
("E->getType()->isFixedPointType() && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10805, __extension__ __PRETTY_FUNCTION__))
;
10806 assert(V.getWidth() == Info.Ctx.getIntWidth(E->getType()) &&(static_cast <bool> (V.getWidth() == Info.Ctx.getIntWidth
(E->getType()) && "Invalid evaluation result.") ? void
(0) : __assert_fail ("V.getWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10807, __extension__ __PRETTY_FUNCTION__))
10807 "Invalid evaluation result.")(static_cast <bool> (V.getWidth() == Info.Ctx.getIntWidth
(E->getType()) && "Invalid evaluation result.") ? void
(0) : __assert_fail ("V.getWidth() == Info.Ctx.getIntWidth(E->getType()) && \"Invalid evaluation result.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10807, __extension__ __PRETTY_FUNCTION__))
;
10808 Result = APValue(V);
10809 return true;
10810 }
10811
10812 //===--------------------------------------------------------------------===//
10813 // Visitor Methods
10814 //===--------------------------------------------------------------------===//
10815
10816 bool VisitFixedPointLiteral(const FixedPointLiteral *E) {
10817 return Success(E->getValue(), E);
10818 }
10819
10820 bool VisitCastExpr(const CastExpr *E);
10821 bool VisitUnaryOperator(const UnaryOperator *E);
10822 bool VisitBinaryOperator(const BinaryOperator *E);
10823};
10824} // end anonymous namespace
10825
10826/// EvaluateIntegerOrLValue - Evaluate an rvalue integral-typed expression, and
10827/// produce either the integer value or a pointer.
10828///
10829/// GCC has a heinous extension which folds casts between pointer types and
10830/// pointer-sized integral types. We support this by allowing the evaluation of
10831/// an integer rvalue to produce a pointer (represented as an lvalue) instead.
10832/// Some simple arithmetic on such values is supported (they are treated much
10833/// like char*).
10834static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result,
10835 EvalInfo &Info) {
10836 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10836, __extension__ __PRETTY_FUNCTION__))
;
10837 assert(E->isPRValue() && E->getType()->isIntegralOrEnumerationType())(static_cast <bool> (E->isPRValue() && E->
getType()->isIntegralOrEnumerationType()) ? void (0) : __assert_fail
("E->isPRValue() && E->getType()->isIntegralOrEnumerationType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10837, __extension__ __PRETTY_FUNCTION__))
;
10838 return IntExprEvaluator(Info, Result).Visit(E);
10839}
10840
10841static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info) {
10842 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10842, __extension__ __PRETTY_FUNCTION__))
;
10843 APValue Val;
10844 if (!EvaluateIntegerOrLValue(E, Val, Info))
10845 return false;
10846 if (!Val.isInt()) {
10847 // FIXME: It would be better to produce the diagnostic for casting
10848 // a pointer to an integer.
10849 Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
10850 return false;
10851 }
10852 Result = Val.getInt();
10853 return true;
10854}
10855
10856bool IntExprEvaluator::VisitSourceLocExpr(const SourceLocExpr *E) {
10857 APValue Evaluated = E->EvaluateInContext(
10858 Info.Ctx, Info.CurrentCall->CurSourceLocExprScope.getDefaultExpr());
10859 return Success(Evaluated, E);
10860}
10861
10862static bool EvaluateFixedPoint(const Expr *E, APFixedPoint &Result,
10863 EvalInfo &Info) {
10864 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10864, __extension__ __PRETTY_FUNCTION__))
;
10865 if (E->getType()->isFixedPointType()) {
10866 APValue Val;
10867 if (!FixedPointExprEvaluator(Info, Val).Visit(E))
10868 return false;
10869 if (!Val.isFixedPoint())
10870 return false;
10871
10872 Result = Val.getFixedPoint();
10873 return true;
10874 }
10875 return false;
10876}
10877
10878static bool EvaluateFixedPointOrInteger(const Expr *E, APFixedPoint &Result,
10879 EvalInfo &Info) {
10880 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10880, __extension__ __PRETTY_FUNCTION__))
;
10881 if (E->getType()->isIntegerType()) {
10882 auto FXSema = Info.Ctx.getFixedPointSemantics(E->getType());
10883 APSInt Val;
10884 if (!EvaluateInteger(E, Val, Info))
10885 return false;
10886 Result = APFixedPoint(Val, FXSema);
10887 return true;
10888 } else if (E->getType()->isFixedPointType()) {
10889 return EvaluateFixedPoint(E, Result, Info);
10890 }
10891 return false;
10892}
10893
10894/// Check whether the given declaration can be directly converted to an integral
10895/// rvalue. If not, no diagnostic is produced; there are other things we can
10896/// try.
10897bool IntExprEvaluator::CheckReferencedDecl(const Expr* E, const Decl* D) {
10898 // Enums are integer constant exprs.
10899 if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(D)) {
10900 // Check for signedness/width mismatches between E type and ECD value.
10901 bool SameSign = (ECD->getInitVal().isSigned()
10902 == E->getType()->isSignedIntegerOrEnumerationType());
10903 bool SameWidth = (ECD->getInitVal().getBitWidth()
10904 == Info.Ctx.getIntWidth(E->getType()));
10905 if (SameSign && SameWidth)
10906 return Success(ECD->getInitVal(), E);
10907 else {
10908 // Get rid of mismatch (otherwise Success assertions will fail)
10909 // by computing a new value matching the type of E.
10910 llvm::APSInt Val = ECD->getInitVal();
10911 if (!SameSign)
10912 Val.setIsSigned(!ECD->getInitVal().isSigned());
10913 if (!SameWidth)
10914 Val = Val.extOrTrunc(Info.Ctx.getIntWidth(E->getType()));
10915 return Success(Val, E);
10916 }
10917 }
10918 return false;
10919}
10920
10921/// Values returned by __builtin_classify_type, chosen to match the values
10922/// produced by GCC's builtin.
10923enum class GCCTypeClass {
10924 None = -1,
10925 Void = 0,
10926 Integer = 1,
10927 // GCC reserves 2 for character types, but instead classifies them as
10928 // integers.
10929 Enum = 3,
10930 Bool = 4,
10931 Pointer = 5,
10932 // GCC reserves 6 for references, but appears to never use it (because
10933 // expressions never have reference type, presumably).
10934 PointerToDataMember = 7,
10935 RealFloat = 8,
10936 Complex = 9,
10937 // GCC reserves 10 for functions, but does not use it since GCC version 6 due
10938 // to decay to pointer. (Prior to version 6 it was only used in C++ mode).
10939 // GCC claims to reserve 11 for pointers to member functions, but *actually*
10940 // uses 12 for that purpose, same as for a class or struct. Maybe it
10941 // internally implements a pointer to member as a struct? Who knows.
10942 PointerToMemberFunction = 12, // Not a bug, see above.
10943 ClassOrStruct = 12,
10944 Union = 13,
10945 // GCC reserves 14 for arrays, but does not use it since GCC version 6 due to
10946 // decay to pointer. (Prior to version 6 it was only used in C++ mode).
10947 // GCC reserves 15 for strings, but actually uses 5 (pointer) for string
10948 // literals.
10949};
10950
10951/// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way
10952/// as GCC.
10953static GCCTypeClass
10954EvaluateBuiltinClassifyType(QualType T, const LangOptions &LangOpts) {
10955 assert(!T->isDependentType() && "unexpected dependent type")(static_cast <bool> (!T->isDependentType() &&
"unexpected dependent type") ? void (0) : __assert_fail ("!T->isDependentType() && \"unexpected dependent type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10955, __extension__ __PRETTY_FUNCTION__))
;
10956
10957 QualType CanTy = T.getCanonicalType();
10958 const BuiltinType *BT = dyn_cast<BuiltinType>(CanTy);
10959
10960 switch (CanTy->getTypeClass()) {
10961#define TYPE(ID, BASE)
10962#define DEPENDENT_TYPE(ID, BASE) case Type::ID:
10963#define NON_CANONICAL_TYPE(ID, BASE) case Type::ID:
10964#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(ID, BASE) case Type::ID:
10965#include "clang/AST/TypeNodes.inc"
10966 case Type::Auto:
10967 case Type::DeducedTemplateSpecialization:
10968 llvm_unreachable("unexpected non-canonical or dependent type")::llvm::llvm_unreachable_internal("unexpected non-canonical or dependent type"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 10968)
;
10969
10970 case Type::Builtin:
10971 switch (BT->getKind()) {
10972#define BUILTIN_TYPE(ID, SINGLETON_ID)
10973#define SIGNED_TYPE(ID, SINGLETON_ID) \
10974 case BuiltinType::ID: return GCCTypeClass::Integer;
10975#define FLOATING_TYPE(ID, SINGLETON_ID) \
10976 case BuiltinType::ID: return GCCTypeClass::RealFloat;
10977#define PLACEHOLDER_TYPE(ID, SINGLETON_ID) \
10978 case BuiltinType::ID: break;
10979#include "clang/AST/BuiltinTypes.def"
10980 case BuiltinType::Void:
10981 return GCCTypeClass::Void;
10982
10983 case BuiltinType::Bool:
10984 return GCCTypeClass::Bool;
10985
10986 case BuiltinType::Char_U:
10987 case BuiltinType::UChar:
10988 case BuiltinType::WChar_U:
10989 case BuiltinType::Char8:
10990 case BuiltinType::Char16:
10991 case BuiltinType::Char32:
10992 case BuiltinType::UShort:
10993 case BuiltinType::UInt:
10994 case BuiltinType::ULong:
10995 case BuiltinType::ULongLong:
10996 case BuiltinType::UInt128:
10997 return GCCTypeClass::Integer;
10998
10999 case BuiltinType::UShortAccum:
11000 case BuiltinType::UAccum:
11001 case BuiltinType::ULongAccum:
11002 case BuiltinType::UShortFract:
11003 case BuiltinType::UFract:
11004 case BuiltinType::ULongFract:
11005 case BuiltinType::SatUShortAccum:
11006 case BuiltinType::SatUAccum:
11007 case BuiltinType::SatULongAccum:
11008 case BuiltinType::SatUShortFract:
11009 case BuiltinType::SatUFract:
11010 case BuiltinType::SatULongFract:
11011 return GCCTypeClass::None;
11012
11013 case BuiltinType::NullPtr:
11014
11015 case BuiltinType::ObjCId:
11016 case BuiltinType::ObjCClass:
11017 case BuiltinType::ObjCSel:
11018#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
11019 case BuiltinType::Id:
11020#include "clang/Basic/OpenCLImageTypes.def"
11021#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
11022 case BuiltinType::Id:
11023#include "clang/Basic/OpenCLExtensionTypes.def"
11024 case BuiltinType::OCLSampler:
11025 case BuiltinType::OCLEvent:
11026 case BuiltinType::OCLClkEvent:
11027 case BuiltinType::OCLQueue:
11028 case BuiltinType::OCLReserveID:
11029#define SVE_TYPE(Name, Id, SingletonId) \
11030 case BuiltinType::Id:
11031#include "clang/Basic/AArch64SVEACLETypes.def"
11032#define PPC_VECTOR_TYPE(Name, Id, Size) \
11033 case BuiltinType::Id:
11034#include "clang/Basic/PPCTypes.def"
11035#define RVV_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
11036#include "clang/Basic/RISCVVTypes.def"
11037 return GCCTypeClass::None;
11038
11039 case BuiltinType::Dependent:
11040 llvm_unreachable("unexpected dependent type")::llvm::llvm_unreachable_internal("unexpected dependent type"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11040)
;
11041 };
11042 llvm_unreachable("unexpected placeholder type")::llvm::llvm_unreachable_internal("unexpected placeholder type"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11042)
;
11043
11044 case Type::Enum:
11045 return LangOpts.CPlusPlus ? GCCTypeClass::Enum : GCCTypeClass::Integer;
11046
11047 case Type::Pointer:
11048 case Type::ConstantArray:
11049 case Type::VariableArray:
11050 case Type::IncompleteArray:
11051 case Type::FunctionNoProto:
11052 case Type::FunctionProto:
11053 return GCCTypeClass::Pointer;
11054
11055 case Type::MemberPointer:
11056 return CanTy->isMemberDataPointerType()
11057 ? GCCTypeClass::PointerToDataMember
11058 : GCCTypeClass::PointerToMemberFunction;
11059
11060 case Type::Complex:
11061 return GCCTypeClass::Complex;
11062
11063 case Type::Record:
11064 return CanTy->isUnionType() ? GCCTypeClass::Union
11065 : GCCTypeClass::ClassOrStruct;
11066
11067 case Type::Atomic:
11068 // GCC classifies _Atomic T the same as T.
11069 return EvaluateBuiltinClassifyType(
11070 CanTy->castAs<AtomicType>()->getValueType(), LangOpts);
11071
11072 case Type::BlockPointer:
11073 case Type::Vector:
11074 case Type::ExtVector:
11075 case Type::ConstantMatrix:
11076 case Type::ObjCObject:
11077 case Type::ObjCInterface:
11078 case Type::ObjCObjectPointer:
11079 case Type::Pipe:
11080 case Type::ExtInt:
11081 // GCC classifies vectors as None. We follow its lead and classify all
11082 // other types that don't fit into the regular classification the same way.
11083 return GCCTypeClass::None;
11084
11085 case Type::LValueReference:
11086 case Type::RValueReference:
11087 llvm_unreachable("invalid type for expression")::llvm::llvm_unreachable_internal("invalid type for expression"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11087)
;
11088 }
11089
11090 llvm_unreachable("unexpected type class")::llvm::llvm_unreachable_internal("unexpected type class", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11090)
;
11091}
11092
11093/// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way
11094/// as GCC.
11095static GCCTypeClass
11096EvaluateBuiltinClassifyType(const CallExpr *E, const LangOptions &LangOpts) {
11097 // If no argument was supplied, default to None. This isn't
11098 // ideal, however it is what gcc does.
11099 if (E->getNumArgs() == 0)
11100 return GCCTypeClass::None;
11101
11102 // FIXME: Bizarrely, GCC treats a call with more than one argument as not
11103 // being an ICE, but still folds it to a constant using the type of the first
11104 // argument.
11105 return EvaluateBuiltinClassifyType(E->getArg(0)->getType(), LangOpts);
11106}
11107
11108/// EvaluateBuiltinConstantPForLValue - Determine the result of
11109/// __builtin_constant_p when applied to the given pointer.
11110///
11111/// A pointer is only "constant" if it is null (or a pointer cast to integer)
11112/// or it points to the first character of a string literal.
11113static bool EvaluateBuiltinConstantPForLValue(const APValue &LV) {
11114 APValue::LValueBase Base = LV.getLValueBase();
11115 if (Base.isNull()) {
11116 // A null base is acceptable.
11117 return true;
11118 } else if (const Expr *E = Base.dyn_cast<const Expr *>()) {
11119 if (!isa<StringLiteral>(E))
11120 return false;
11121 return LV.getLValueOffset().isZero();
11122 } else if (Base.is<TypeInfoLValue>()) {
11123 // Surprisingly, GCC considers __builtin_constant_p(&typeid(int)) to
11124 // evaluate to true.
11125 return true;
11126 } else {
11127 // Any other base is not constant enough for GCC.
11128 return false;
11129 }
11130}
11131
11132/// EvaluateBuiltinConstantP - Evaluate __builtin_constant_p as similarly to
11133/// GCC as we can manage.
11134static bool EvaluateBuiltinConstantP(EvalInfo &Info, const Expr *Arg) {
11135 // This evaluation is not permitted to have side-effects, so evaluate it in
11136 // a speculative evaluation context.
11137 SpeculativeEvaluationRAII SpeculativeEval(Info);
11138
11139 // Constant-folding is always enabled for the operand of __builtin_constant_p
11140 // (even when the enclosing evaluation context otherwise requires a strict
11141 // language-specific constant expression).
11142 FoldConstant Fold(Info, true);
11143
11144 QualType ArgType = Arg->getType();
11145
11146 // __builtin_constant_p always has one operand. The rules which gcc follows
11147 // are not precisely documented, but are as follows:
11148 //
11149 // - If the operand is of integral, floating, complex or enumeration type,
11150 // and can be folded to a known value of that type, it returns 1.
11151 // - If the operand can be folded to a pointer to the first character
11152 // of a string literal (or such a pointer cast to an integral type)
11153 // or to a null pointer or an integer cast to a pointer, it returns 1.
11154 //
11155 // Otherwise, it returns 0.
11156 //
11157 // FIXME: GCC also intends to return 1 for literals of aggregate types, but
11158 // its support for this did not work prior to GCC 9 and is not yet well
11159 // understood.
11160 if (ArgType->isIntegralOrEnumerationType() || ArgType->isFloatingType() ||
11161 ArgType->isAnyComplexType() || ArgType->isPointerType() ||
11162 ArgType->isNullPtrType()) {
11163 APValue V;
11164 if (!::EvaluateAsRValue(Info, Arg, V) || Info.EvalStatus.HasSideEffects) {
11165 Fold.keepDiagnostics();
11166 return false;
11167 }
11168
11169 // For a pointer (possibly cast to integer), there are special rules.
11170 if (V.getKind() == APValue::LValue)
11171 return EvaluateBuiltinConstantPForLValue(V);
11172
11173 // Otherwise, any constant value is good enough.
11174 return V.hasValue();
11175 }
11176
11177 // Anything else isn't considered to be sufficiently constant.
11178 return false;
11179}
11180
11181/// Retrieves the "underlying object type" of the given expression,
11182/// as used by __builtin_object_size.
11183static QualType getObjectType(APValue::LValueBase B) {
11184 if (const ValueDecl *D = B.dyn_cast<const ValueDecl*>()) {
11185 if (const VarDecl *VD = dyn_cast<VarDecl>(D))
11186 return VD->getType();
11187 } else if (const Expr *E = B.dyn_cast<const Expr*>()) {
11188 if (isa<CompoundLiteralExpr>(E))
11189 return E->getType();
11190 } else if (B.is<TypeInfoLValue>()) {
11191 return B.getTypeInfoType();
11192 } else if (B.is<DynamicAllocLValue>()) {
11193 return B.getDynamicAllocType();
11194 }
11195
11196 return QualType();
11197}
11198
11199/// A more selective version of E->IgnoreParenCasts for
11200/// tryEvaluateBuiltinObjectSize. This ignores some casts/parens that serve only
11201/// to change the type of E.
11202/// Ex. For E = `(short*)((char*)(&foo))`, returns `&foo`
11203///
11204/// Always returns an RValue with a pointer representation.
11205static const Expr *ignorePointerCastsAndParens(const Expr *E) {
11206 assert(E->isPRValue() && E->getType()->hasPointerRepresentation())(static_cast <bool> (E->isPRValue() && E->
getType()->hasPointerRepresentation()) ? void (0) : __assert_fail
("E->isPRValue() && E->getType()->hasPointerRepresentation()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11206, __extension__ __PRETTY_FUNCTION__))
;
11207
11208 auto *NoParens = E->IgnoreParens();
11209 auto *Cast = dyn_cast<CastExpr>(NoParens);
11210 if (Cast == nullptr)
11211 return NoParens;
11212
11213 // We only conservatively allow a few kinds of casts, because this code is
11214 // inherently a simple solution that seeks to support the common case.
11215 auto CastKind = Cast->getCastKind();
11216 if (CastKind != CK_NoOp && CastKind != CK_BitCast &&
11217 CastKind != CK_AddressSpaceConversion)
11218 return NoParens;
11219
11220 auto *SubExpr = Cast->getSubExpr();
11221 if (!SubExpr->getType()->hasPointerRepresentation() || !SubExpr->isPRValue())
11222 return NoParens;
11223 return ignorePointerCastsAndParens(SubExpr);
11224}
11225
11226/// Checks to see if the given LValue's Designator is at the end of the LValue's
11227/// record layout. e.g.
11228/// struct { struct { int a, b; } fst, snd; } obj;
11229/// obj.fst // no
11230/// obj.snd // yes
11231/// obj.fst.a // no
11232/// obj.fst.b // no
11233/// obj.snd.a // no
11234/// obj.snd.b // yes
11235///
11236/// Please note: this function is specialized for how __builtin_object_size
11237/// views "objects".
11238///
11239/// If this encounters an invalid RecordDecl or otherwise cannot determine the
11240/// correct result, it will always return true.
11241static bool isDesignatorAtObjectEnd(const ASTContext &Ctx, const LValue &LVal) {
11242 assert(!LVal.Designator.Invalid)(static_cast <bool> (!LVal.Designator.Invalid) ? void (
0) : __assert_fail ("!LVal.Designator.Invalid", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11242, __extension__ __PRETTY_FUNCTION__))
;
11243
11244 auto IsLastOrInvalidFieldDecl = [&Ctx](const FieldDecl *FD, bool &Invalid) {
11245 const RecordDecl *Parent = FD->getParent();
11246 Invalid = Parent->isInvalidDecl();
11247 if (Invalid || Parent->isUnion())
11248 return true;
11249 const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(Parent);
11250 return FD->getFieldIndex() + 1 == Layout.getFieldCount();
11251 };
11252
11253 auto &Base = LVal.getLValueBase();
11254 if (auto *ME = dyn_cast_or_null<MemberExpr>(Base.dyn_cast<const Expr *>())) {
11255 if (auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
11256 bool Invalid;
11257 if (!IsLastOrInvalidFieldDecl(FD, Invalid))
11258 return Invalid;
11259 } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(ME->getMemberDecl())) {
11260 for (auto *FD : IFD->chain()) {
11261 bool Invalid;
11262 if (!IsLastOrInvalidFieldDecl(cast<FieldDecl>(FD), Invalid))
11263 return Invalid;
11264 }
11265 }
11266 }
11267
11268 unsigned I = 0;
11269 QualType BaseType = getType(Base);
11270 if (LVal.Designator.FirstEntryIsAnUnsizedArray) {
11271 // If we don't know the array bound, conservatively assume we're looking at
11272 // the final array element.
11273 ++I;
11274 if (BaseType->isIncompleteArrayType())
11275 BaseType = Ctx.getAsArrayType(BaseType)->getElementType();
11276 else
11277 BaseType = BaseType->castAs<PointerType>()->getPointeeType();
11278 }
11279
11280 for (unsigned E = LVal.Designator.Entries.size(); I != E; ++I) {
11281 const auto &Entry = LVal.Designator.Entries[I];
11282 if (BaseType->isArrayType()) {
11283 // Because __builtin_object_size treats arrays as objects, we can ignore
11284 // the index iff this is the last array in the Designator.
11285 if (I + 1 == E)
11286 return true;
11287 const auto *CAT = cast<ConstantArrayType>(Ctx.getAsArrayType(BaseType));
11288 uint64_t Index = Entry.getAsArrayIndex();
11289 if (Index + 1 != CAT->getSize())
11290 return false;
11291 BaseType = CAT->getElementType();
11292 } else if (BaseType->isAnyComplexType()) {
11293 const auto *CT = BaseType->castAs<ComplexType>();
11294 uint64_t Index = Entry.getAsArrayIndex();
11295 if (Index != 1)
11296 return false;
11297 BaseType = CT->getElementType();
11298 } else if (auto *FD = getAsField(Entry)) {
11299 bool Invalid;
11300 if (!IsLastOrInvalidFieldDecl(FD, Invalid))
11301 return Invalid;
11302 BaseType = FD->getType();
11303 } else {
11304 assert(getAsBaseClass(Entry) && "Expecting cast to a base class")(static_cast <bool> (getAsBaseClass(Entry) && "Expecting cast to a base class"
) ? void (0) : __assert_fail ("getAsBaseClass(Entry) && \"Expecting cast to a base class\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11304, __extension__ __PRETTY_FUNCTION__))
;
11305 return false;
11306 }
11307 }
11308 return true;
11309}
11310
11311/// Tests to see if the LValue has a user-specified designator (that isn't
11312/// necessarily valid). Note that this always returns 'true' if the LValue has
11313/// an unsized array as its first designator entry, because there's currently no
11314/// way to tell if the user typed *foo or foo[0].
11315static bool refersToCompleteObject(const LValue &LVal) {
11316 if (LVal.Designator.Invalid)
11317 return false;
11318
11319 if (!LVal.Designator.Entries.empty())
11320 return LVal.Designator.isMostDerivedAnUnsizedArray();
11321
11322 if (!LVal.InvalidBase)
11323 return true;
11324
11325 // If `E` is a MemberExpr, then the first part of the designator is hiding in
11326 // the LValueBase.
11327 const auto *E = LVal.Base.dyn_cast<const Expr *>();
11328 return !E || !isa<MemberExpr>(E);
11329}
11330
11331/// Attempts to detect a user writing into a piece of memory that's impossible
11332/// to figure out the size of by just using types.
11333static bool isUserWritingOffTheEnd(const ASTContext &Ctx, const LValue &LVal) {
11334 const SubobjectDesignator &Designator = LVal.Designator;
11335 // Notes:
11336 // - Users can only write off of the end when we have an invalid base. Invalid
11337 // bases imply we don't know where the memory came from.
11338 // - We used to be a bit more aggressive here; we'd only be conservative if
11339 // the array at the end was flexible, or if it had 0 or 1 elements. This
11340 // broke some common standard library extensions (PR30346), but was
11341 // otherwise seemingly fine. It may be useful to reintroduce this behavior
11342 // with some sort of list. OTOH, it seems that GCC is always
11343 // conservative with the last element in structs (if it's an array), so our
11344 // current behavior is more compatible than an explicit list approach would
11345 // be.
11346 return LVal.InvalidBase &&
11347 Designator.Entries.size() == Designator.MostDerivedPathLength &&
11348 Designator.MostDerivedIsArrayElement &&
11349 isDesignatorAtObjectEnd(Ctx, LVal);
11350}
11351
11352/// Converts the given APInt to CharUnits, assuming the APInt is unsigned.
11353/// Fails if the conversion would cause loss of precision.
11354static bool convertUnsignedAPIntToCharUnits(const llvm::APInt &Int,
11355 CharUnits &Result) {
11356 auto CharUnitsMax = std::numeric_limits<CharUnits::QuantityType>::max();
11357 if (Int.ugt(CharUnitsMax))
11358 return false;
11359 Result = CharUnits::fromQuantity(Int.getZExtValue());
11360 return true;
11361}
11362
11363/// Helper for tryEvaluateBuiltinObjectSize -- Given an LValue, this will
11364/// determine how many bytes exist from the beginning of the object to either
11365/// the end of the current subobject, or the end of the object itself, depending
11366/// on what the LValue looks like + the value of Type.
11367///
11368/// If this returns false, the value of Result is undefined.
11369static bool determineEndOffset(EvalInfo &Info, SourceLocation ExprLoc,
11370 unsigned Type, const LValue &LVal,
11371 CharUnits &EndOffset) {
11372 bool DetermineForCompleteObject = refersToCompleteObject(LVal);
11373
11374 auto CheckedHandleSizeof = [&](QualType Ty, CharUnits &Result) {
11375 if (Ty.isNull() || Ty->isIncompleteType() || Ty->isFunctionType())
11376 return false;
11377 return HandleSizeof(Info, ExprLoc, Ty, Result);
11378 };
11379
11380 // We want to evaluate the size of the entire object. This is a valid fallback
11381 // for when Type=1 and the designator is invalid, because we're asked for an
11382 // upper-bound.
11383 if (!(Type & 1) || LVal.Designator.Invalid || DetermineForCompleteObject) {
11384 // Type=3 wants a lower bound, so we can't fall back to this.
11385 if (Type == 3 && !DetermineForCompleteObject)
11386 return false;
11387
11388 llvm::APInt APEndOffset;
11389 if (isBaseAnAllocSizeCall(LVal.getLValueBase()) &&
11390 getBytesReturnedByAllocSizeCall(Info.Ctx, LVal, APEndOffset))
11391 return convertUnsignedAPIntToCharUnits(APEndOffset, EndOffset);
11392
11393 if (LVal.InvalidBase)
11394 return false;
11395
11396 QualType BaseTy = getObjectType(LVal.getLValueBase());
11397 return CheckedHandleSizeof(BaseTy, EndOffset);
11398 }
11399
11400 // We want to evaluate the size of a subobject.
11401 const SubobjectDesignator &Designator = LVal.Designator;
11402
11403 // The following is a moderately common idiom in C:
11404 //
11405 // struct Foo { int a; char c[1]; };
11406 // struct Foo *F = (struct Foo *)malloc(sizeof(struct Foo) + strlen(Bar));
11407 // strcpy(&F->c[0], Bar);
11408 //
11409 // In order to not break too much legacy code, we need to support it.
11410 if (isUserWritingOffTheEnd(Info.Ctx, LVal)) {
11411 // If we can resolve this to an alloc_size call, we can hand that back,
11412 // because we know for certain how many bytes there are to write to.
11413 llvm::APInt APEndOffset;
11414 if (isBaseAnAllocSizeCall(LVal.getLValueBase()) &&
11415 getBytesReturnedByAllocSizeCall(Info.Ctx, LVal, APEndOffset))
11416 return convertUnsignedAPIntToCharUnits(APEndOffset, EndOffset);
11417
11418 // If we cannot determine the size of the initial allocation, then we can't
11419 // given an accurate upper-bound. However, we are still able to give
11420 // conservative lower-bounds for Type=3.
11421 if (Type == 1)
11422 return false;
11423 }
11424
11425 CharUnits BytesPerElem;
11426 if (!CheckedHandleSizeof(Designator.MostDerivedType, BytesPerElem))
11427 return false;
11428
11429 // According to the GCC documentation, we want the size of the subobject
11430 // denoted by the pointer. But that's not quite right -- what we actually
11431 // want is the size of the immediately-enclosing array, if there is one.
11432 int64_t ElemsRemaining;
11433 if (Designator.MostDerivedIsArrayElement &&
11434 Designator.Entries.size() == Designator.MostDerivedPathLength) {
11435 uint64_t ArraySize = Designator.getMostDerivedArraySize();
11436 uint64_t ArrayIndex = Designator.Entries.back().getAsArrayIndex();
11437 ElemsRemaining = ArraySize <= ArrayIndex ? 0 : ArraySize - ArrayIndex;
11438 } else {
11439 ElemsRemaining = Designator.isOnePastTheEnd() ? 0 : 1;
11440 }
11441
11442 EndOffset = LVal.getLValueOffset() + BytesPerElem * ElemsRemaining;
11443 return true;
11444}
11445
11446/// Tries to evaluate the __builtin_object_size for @p E. If successful,
11447/// returns true and stores the result in @p Size.
11448///
11449/// If @p WasError is non-null, this will report whether the failure to evaluate
11450/// is to be treated as an Error in IntExprEvaluator.
11451static bool tryEvaluateBuiltinObjectSize(const Expr *E, unsigned Type,
11452 EvalInfo &Info, uint64_t &Size) {
11453 // Determine the denoted object.
11454 LValue LVal;
11455 {
11456 // The operand of __builtin_object_size is never evaluated for side-effects.
11457 // If there are any, but we can determine the pointed-to object anyway, then
11458 // ignore the side-effects.
11459 SpeculativeEvaluationRAII SpeculativeEval(Info);
11460 IgnoreSideEffectsRAII Fold(Info);
11461
11462 if (E->isGLValue()) {
11463 // It's possible for us to be given GLValues if we're called via
11464 // Expr::tryEvaluateObjectSize.
11465 APValue RVal;
11466 if (!EvaluateAsRValue(Info, E, RVal))
11467 return false;
11468 LVal.setFrom(Info.Ctx, RVal);
11469 } else if (!EvaluatePointer(ignorePointerCastsAndParens(E), LVal, Info,
11470 /*InvalidBaseOK=*/true))
11471 return false;
11472 }
11473
11474 // If we point to before the start of the object, there are no accessible
11475 // bytes.
11476 if (LVal.getLValueOffset().isNegative()) {
11477 Size = 0;
11478 return true;
11479 }
11480
11481 CharUnits EndOffset;
11482 if (!determineEndOffset(Info, E->getExprLoc(), Type, LVal, EndOffset))
11483 return false;
11484
11485 // If we've fallen outside of the end offset, just pretend there's nothing to
11486 // write to/read from.
11487 if (EndOffset <= LVal.getLValueOffset())
11488 Size = 0;
11489 else
11490 Size = (EndOffset - LVal.getLValueOffset()).getQuantity();
11491 return true;
11492}
11493
11494bool IntExprEvaluator::VisitCallExpr(const CallExpr *E) {
11495 if (unsigned BuiltinOp = E->getBuiltinCallee())
11496 return VisitBuiltinCallExpr(E, BuiltinOp);
11497
11498 return ExprEvaluatorBaseTy::VisitCallExpr(E);
11499}
11500
11501static bool getBuiltinAlignArguments(const CallExpr *E, EvalInfo &Info,
11502 APValue &Val, APSInt &Alignment) {
11503 QualType SrcTy = E->getArg(0)->getType();
11504 if (!getAlignmentArgument(E->getArg(1), SrcTy, Info, Alignment))
11505 return false;
11506 // Even though we are evaluating integer expressions we could get a pointer
11507 // argument for the __builtin_is_aligned() case.
11508 if (SrcTy->isPointerType()) {
11509 LValue Ptr;
11510 if (!EvaluatePointer(E->getArg(0), Ptr, Info))
11511 return false;
11512 Ptr.moveInto(Val);
11513 } else if (!SrcTy->isIntegralOrEnumerationType()) {
11514 Info.FFDiag(E->getArg(0));
11515 return false;
11516 } else {
11517 APSInt SrcInt;
11518 if (!EvaluateInteger(E->getArg(0), SrcInt, Info))
11519 return false;
11520 assert(SrcInt.getBitWidth() >= Alignment.getBitWidth() &&(static_cast <bool> (SrcInt.getBitWidth() >= Alignment
.getBitWidth() && "Bit widths must be the same") ? void
(0) : __assert_fail ("SrcInt.getBitWidth() >= Alignment.getBitWidth() && \"Bit widths must be the same\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11521, __extension__ __PRETTY_FUNCTION__))
11521 "Bit widths must be the same")(static_cast <bool> (SrcInt.getBitWidth() >= Alignment
.getBitWidth() && "Bit widths must be the same") ? void
(0) : __assert_fail ("SrcInt.getBitWidth() >= Alignment.getBitWidth() && \"Bit widths must be the same\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11521, __extension__ __PRETTY_FUNCTION__))
;
11522 Val = APValue(SrcInt);
11523 }
11524 assert(Val.hasValue())(static_cast <bool> (Val.hasValue()) ? void (0) : __assert_fail
("Val.hasValue()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11524, __extension__ __PRETTY_FUNCTION__))
;
11525 return true;
11526}
11527
11528bool IntExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
11529 unsigned BuiltinOp) {
11530 switch (BuiltinOp) {
11531 default:
11532 return ExprEvaluatorBaseTy::VisitCallExpr(E);
11533
11534 case Builtin::BI__builtin_dynamic_object_size:
11535 case Builtin::BI__builtin_object_size: {
11536 // The type was checked when we built the expression.
11537 unsigned Type =
11538 E->getArg(1)->EvaluateKnownConstInt(Info.Ctx).getZExtValue();
11539 assert(Type <= 3 && "unexpected type")(static_cast <bool> (Type <= 3 && "unexpected type"
) ? void (0) : __assert_fail ("Type <= 3 && \"unexpected type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11539, __extension__ __PRETTY_FUNCTION__))
;
11540
11541 uint64_t Size;
11542 if (tryEvaluateBuiltinObjectSize(E->getArg(0), Type, Info, Size))
11543 return Success(Size, E);
11544
11545 if (E->getArg(0)->HasSideEffects(Info.Ctx))
11546 return Success((Type & 2) ? 0 : -1, E);
11547
11548 // Expression had no side effects, but we couldn't statically determine the
11549 // size of the referenced object.
11550 switch (Info.EvalMode) {
11551 case EvalInfo::EM_ConstantExpression:
11552 case EvalInfo::EM_ConstantFold:
11553 case EvalInfo::EM_IgnoreSideEffects:
11554 // Leave it to IR generation.
11555 return Error(E);
11556 case EvalInfo::EM_ConstantExpressionUnevaluated:
11557 // Reduce it to a constant now.
11558 return Success((Type & 2) ? 0 : -1, E);
11559 }
11560
11561 llvm_unreachable("unexpected EvalMode")::llvm::llvm_unreachable_internal("unexpected EvalMode", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11561)
;
11562 }
11563
11564 case Builtin::BI__builtin_os_log_format_buffer_size: {
11565 analyze_os_log::OSLogBufferLayout Layout;
11566 analyze_os_log::computeOSLogBufferLayout(Info.Ctx, E, Layout);
11567 return Success(Layout.size().getQuantity(), E);
11568 }
11569
11570 case Builtin::BI__builtin_is_aligned: {
11571 APValue Src;
11572 APSInt Alignment;
11573 if (!getBuiltinAlignArguments(E, Info, Src, Alignment))
11574 return false;
11575 if (Src.isLValue()) {
11576 // If we evaluated a pointer, check the minimum known alignment.
11577 LValue Ptr;
11578 Ptr.setFrom(Info.Ctx, Src);
11579 CharUnits BaseAlignment = getBaseAlignment(Info, Ptr);
11580 CharUnits PtrAlign = BaseAlignment.alignmentAtOffset(Ptr.Offset);
11581 // We can return true if the known alignment at the computed offset is
11582 // greater than the requested alignment.
11583 assert(PtrAlign.isPowerOfTwo())(static_cast <bool> (PtrAlign.isPowerOfTwo()) ? void (0
) : __assert_fail ("PtrAlign.isPowerOfTwo()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11583, __extension__ __PRETTY_FUNCTION__))
;
11584 assert(Alignment.isPowerOf2())(static_cast <bool> (Alignment.isPowerOf2()) ? void (0)
: __assert_fail ("Alignment.isPowerOf2()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11584, __extension__ __PRETTY_FUNCTION__))
;
11585 if (PtrAlign.getQuantity() >= Alignment)
11586 return Success(1, E);
11587 // If the alignment is not known to be sufficient, some cases could still
11588 // be aligned at run time. However, if the requested alignment is less or
11589 // equal to the base alignment and the offset is not aligned, we know that
11590 // the run-time value can never be aligned.
11591 if (BaseAlignment.getQuantity() >= Alignment &&
11592 PtrAlign.getQuantity() < Alignment)
11593 return Success(0, E);
11594 // Otherwise we can't infer whether the value is sufficiently aligned.
11595 // TODO: __builtin_is_aligned(__builtin_align_{down,up{(expr, N), N)
11596 // in cases where we can't fully evaluate the pointer.
11597 Info.FFDiag(E->getArg(0), diag::note_constexpr_alignment_compute)
11598 << Alignment;
11599 return false;
11600 }
11601 assert(Src.isInt())(static_cast <bool> (Src.isInt()) ? void (0) : __assert_fail
("Src.isInt()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11601, __extension__ __PRETTY_FUNCTION__))
;
11602 return Success((Src.getInt() & (Alignment - 1)) == 0 ? 1 : 0, E);
11603 }
11604 case Builtin::BI__builtin_align_up: {
11605 APValue Src;
11606 APSInt Alignment;
11607 if (!getBuiltinAlignArguments(E, Info, Src, Alignment))
11608 return false;
11609 if (!Src.isInt())
11610 return Error(E);
11611 APSInt AlignedVal =
11612 APSInt((Src.getInt() + (Alignment - 1)) & ~(Alignment - 1),
11613 Src.getInt().isUnsigned());
11614 assert(AlignedVal.getBitWidth() == Src.getInt().getBitWidth())(static_cast <bool> (AlignedVal.getBitWidth() == Src.getInt
().getBitWidth()) ? void (0) : __assert_fail ("AlignedVal.getBitWidth() == Src.getInt().getBitWidth()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11614, __extension__ __PRETTY_FUNCTION__))
;
11615 return Success(AlignedVal, E);
11616 }
11617 case Builtin::BI__builtin_align_down: {
11618 APValue Src;
11619 APSInt Alignment;
11620 if (!getBuiltinAlignArguments(E, Info, Src, Alignment))
11621 return false;
11622 if (!Src.isInt())
11623 return Error(E);
11624 APSInt AlignedVal =
11625 APSInt(Src.getInt() & ~(Alignment - 1), Src.getInt().isUnsigned());
11626 assert(AlignedVal.getBitWidth() == Src.getInt().getBitWidth())(static_cast <bool> (AlignedVal.getBitWidth() == Src.getInt
().getBitWidth()) ? void (0) : __assert_fail ("AlignedVal.getBitWidth() == Src.getInt().getBitWidth()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11626, __extension__ __PRETTY_FUNCTION__))
;
11627 return Success(AlignedVal, E);
11628 }
11629
11630 case Builtin::BI__builtin_bitreverse8:
11631 case Builtin::BI__builtin_bitreverse16:
11632 case Builtin::BI__builtin_bitreverse32:
11633 case Builtin::BI__builtin_bitreverse64: {
11634 APSInt Val;
11635 if (!EvaluateInteger(E->getArg(0), Val, Info))
11636 return false;
11637
11638 return Success(Val.reverseBits(), E);
11639 }
11640
11641 case Builtin::BI__builtin_bswap16:
11642 case Builtin::BI__builtin_bswap32:
11643 case Builtin::BI__builtin_bswap64: {
11644 APSInt Val;
11645 if (!EvaluateInteger(E->getArg(0), Val, Info))
11646 return false;
11647
11648 return Success(Val.byteSwap(), E);
11649 }
11650
11651 case Builtin::BI__builtin_classify_type:
11652 return Success((int)EvaluateBuiltinClassifyType(E, Info.getLangOpts()), E);
11653
11654 case Builtin::BI__builtin_clrsb:
11655 case Builtin::BI__builtin_clrsbl:
11656 case Builtin::BI__builtin_clrsbll: {
11657 APSInt Val;
11658 if (!EvaluateInteger(E->getArg(0), Val, Info))
11659 return false;
11660
11661 return Success(Val.getBitWidth() - Val.getMinSignedBits(), E);
11662 }
11663
11664 case Builtin::BI__builtin_clz:
11665 case Builtin::BI__builtin_clzl:
11666 case Builtin::BI__builtin_clzll:
11667 case Builtin::BI__builtin_clzs: {
11668 APSInt Val;
11669 if (!EvaluateInteger(E->getArg(0), Val, Info))
11670 return false;
11671 if (!Val)
11672 return Error(E);
11673
11674 return Success(Val.countLeadingZeros(), E);
11675 }
11676
11677 case Builtin::BI__builtin_constant_p: {
11678 const Expr *Arg = E->getArg(0);
11679 if (EvaluateBuiltinConstantP(Info, Arg))
11680 return Success(true, E);
11681 if (Info.InConstantContext || Arg->HasSideEffects(Info.Ctx)) {
11682 // Outside a constant context, eagerly evaluate to false in the presence
11683 // of side-effects in order to avoid -Wunsequenced false-positives in
11684 // a branch on __builtin_constant_p(expr).
11685 return Success(false, E);
11686 }
11687 Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
11688 return false;
11689 }
11690
11691 case Builtin::BI__builtin_is_constant_evaluated: {
11692 const auto *Callee = Info.CurrentCall->getCallee();
11693 if (Info.InConstantContext && !Info.CheckingPotentialConstantExpression &&
11694 (Info.CallStackDepth == 1 ||
11695 (Info.CallStackDepth == 2 && Callee->isInStdNamespace() &&
11696 Callee->getIdentifier() &&
11697 Callee->getIdentifier()->isStr("is_constant_evaluated")))) {
11698 // FIXME: Find a better way to avoid duplicated diagnostics.
11699 if (Info.EvalStatus.Diag)
11700 Info.report((Info.CallStackDepth == 1) ? E->getExprLoc()
11701 : Info.CurrentCall->CallLoc,
11702 diag::warn_is_constant_evaluated_always_true_constexpr)
11703 << (Info.CallStackDepth == 1 ? "__builtin_is_constant_evaluated"
11704 : "std::is_constant_evaluated");
11705 }
11706
11707 return Success(Info.InConstantContext, E);
11708 }
11709
11710 case Builtin::BI__builtin_ctz:
11711 case Builtin::BI__builtin_ctzl:
11712 case Builtin::BI__builtin_ctzll:
11713 case Builtin::BI__builtin_ctzs: {
11714 APSInt Val;
11715 if (!EvaluateInteger(E->getArg(0), Val, Info))
11716 return false;
11717 if (!Val)
11718 return Error(E);
11719
11720 return Success(Val.countTrailingZeros(), E);
11721 }
11722
11723 case Builtin::BI__builtin_eh_return_data_regno: {
11724 int Operand = E->getArg(0)->EvaluateKnownConstInt(Info.Ctx).getZExtValue();
11725 Operand = Info.Ctx.getTargetInfo().getEHDataRegisterNumber(Operand);
11726 return Success(Operand, E);
11727 }
11728
11729 case Builtin::BI__builtin_expect:
11730 case Builtin::BI__builtin_expect_with_probability:
11731 return Visit(E->getArg(0));
11732
11733 case Builtin::BI__builtin_ffs:
11734 case Builtin::BI__builtin_ffsl:
11735 case Builtin::BI__builtin_ffsll: {
11736 APSInt Val;
11737 if (!EvaluateInteger(E->getArg(0), Val, Info))
11738 return false;
11739
11740 unsigned N = Val.countTrailingZeros();
11741 return Success(N == Val.getBitWidth() ? 0 : N + 1, E);
11742 }
11743
11744 case Builtin::BI__builtin_fpclassify: {
11745 APFloat Val(0.0);
11746 if (!EvaluateFloat(E->getArg(5), Val, Info))
11747 return false;
11748 unsigned Arg;
11749 switch (Val.getCategory()) {
11750 case APFloat::fcNaN: Arg = 0; break;
11751 case APFloat::fcInfinity: Arg = 1; break;
11752 case APFloat::fcNormal: Arg = Val.isDenormal() ? 3 : 2; break;
11753 case APFloat::fcZero: Arg = 4; break;
11754 }
11755 return Visit(E->getArg(Arg));
11756 }
11757
11758 case Builtin::BI__builtin_isinf_sign: {
11759 APFloat Val(0.0);
11760 return EvaluateFloat(E->getArg(0), Val, Info) &&
11761 Success(Val.isInfinity() ? (Val.isNegative() ? -1 : 1) : 0, E);
11762 }
11763
11764 case Builtin::BI__builtin_isinf: {
11765 APFloat Val(0.0);
11766 return EvaluateFloat(E->getArg(0), Val, Info) &&
11767 Success(Val.isInfinity() ? 1 : 0, E);
11768 }
11769
11770 case Builtin::BI__builtin_isfinite: {
11771 APFloat Val(0.0);
11772 return EvaluateFloat(E->getArg(0), Val, Info) &&
11773 Success(Val.isFinite() ? 1 : 0, E);
11774 }
11775
11776 case Builtin::BI__builtin_isnan: {
11777 APFloat Val(0.0);
11778 return EvaluateFloat(E->getArg(0), Val, Info) &&
11779 Success(Val.isNaN() ? 1 : 0, E);
11780 }
11781
11782 case Builtin::BI__builtin_isnormal: {
11783 APFloat Val(0.0);
11784 return EvaluateFloat(E->getArg(0), Val, Info) &&
11785 Success(Val.isNormal() ? 1 : 0, E);
11786 }
11787
11788 case Builtin::BI__builtin_parity:
11789 case Builtin::BI__builtin_parityl:
11790 case Builtin::BI__builtin_parityll: {
11791 APSInt Val;
11792 if (!EvaluateInteger(E->getArg(0), Val, Info))
11793 return false;
11794
11795 return Success(Val.countPopulation() % 2, E);
11796 }
11797
11798 case Builtin::BI__builtin_popcount:
11799 case Builtin::BI__builtin_popcountl:
11800 case Builtin::BI__builtin_popcountll: {
11801 APSInt Val;
11802 if (!EvaluateInteger(E->getArg(0), Val, Info))
11803 return false;
11804
11805 return Success(Val.countPopulation(), E);
11806 }
11807
11808 case Builtin::BI__builtin_rotateleft8:
11809 case Builtin::BI__builtin_rotateleft16:
11810 case Builtin::BI__builtin_rotateleft32:
11811 case Builtin::BI__builtin_rotateleft64:
11812 case Builtin::BI_rotl8: // Microsoft variants of rotate right
11813 case Builtin::BI_rotl16:
11814 case Builtin::BI_rotl:
11815 case Builtin::BI_lrotl:
11816 case Builtin::BI_rotl64: {
11817 APSInt Val, Amt;
11818 if (!EvaluateInteger(E->getArg(0), Val, Info) ||
11819 !EvaluateInteger(E->getArg(1), Amt, Info))
11820 return false;
11821
11822 return Success(Val.rotl(Amt.urem(Val.getBitWidth())), E);
11823 }
11824
11825 case Builtin::BI__builtin_rotateright8:
11826 case Builtin::BI__builtin_rotateright16:
11827 case Builtin::BI__builtin_rotateright32:
11828 case Builtin::BI__builtin_rotateright64:
11829 case Builtin::BI_rotr8: // Microsoft variants of rotate right
11830 case Builtin::BI_rotr16:
11831 case Builtin::BI_rotr:
11832 case Builtin::BI_lrotr:
11833 case Builtin::BI_rotr64: {
11834 APSInt Val, Amt;
11835 if (!EvaluateInteger(E->getArg(0), Val, Info) ||
11836 !EvaluateInteger(E->getArg(1), Amt, Info))
11837 return false;
11838
11839 return Success(Val.rotr(Amt.urem(Val.getBitWidth())), E);
11840 }
11841
11842 case Builtin::BIstrlen:
11843 case Builtin::BIwcslen:
11844 // A call to strlen is not a constant expression.
11845 if (Info.getLangOpts().CPlusPlus11)
11846 Info.CCEDiag(E, diag::note_constexpr_invalid_function)
11847 << /*isConstexpr*/0 << /*isConstructor*/0
11848 << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
11849 else
11850 Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
11851 LLVM_FALLTHROUGH[[gnu::fallthrough]];
11852 case Builtin::BI__builtin_strlen:
11853 case Builtin::BI__builtin_wcslen: {
11854 // As an extension, we support __builtin_strlen() as a constant expression,
11855 // and support folding strlen() to a constant.
11856 uint64_t StrLen;
11857 if (EvaluateBuiltinStrLen(E->getArg(0), StrLen, Info))
11858 return Success(StrLen, E);
11859 return false;
11860 }
11861
11862 case Builtin::BIstrcmp:
11863 case Builtin::BIwcscmp:
11864 case Builtin::BIstrncmp:
11865 case Builtin::BIwcsncmp:
11866 case Builtin::BImemcmp:
11867 case Builtin::BIbcmp:
11868 case Builtin::BIwmemcmp:
11869 // A call to strlen is not a constant expression.
11870 if (Info.getLangOpts().CPlusPlus11)
11871 Info.CCEDiag(E, diag::note_constexpr_invalid_function)
11872 << /*isConstexpr*/0 << /*isConstructor*/0
11873 << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'");
11874 else
11875 Info.CCEDiag(E, diag::note_invalid_subexpr_in_const_expr);
11876 LLVM_FALLTHROUGH[[gnu::fallthrough]];
11877 case Builtin::BI__builtin_strcmp:
11878 case Builtin::BI__builtin_wcscmp:
11879 case Builtin::BI__builtin_strncmp:
11880 case Builtin::BI__builtin_wcsncmp:
11881 case Builtin::BI__builtin_memcmp:
11882 case Builtin::BI__builtin_bcmp:
11883 case Builtin::BI__builtin_wmemcmp: {
11884 LValue String1, String2;
11885 if (!EvaluatePointer(E->getArg(0), String1, Info) ||
11886 !EvaluatePointer(E->getArg(1), String2, Info))
11887 return false;
11888
11889 uint64_t MaxLength = uint64_t(-1);
11890 if (BuiltinOp != Builtin::BIstrcmp &&
11891 BuiltinOp != Builtin::BIwcscmp &&
11892 BuiltinOp != Builtin::BI__builtin_strcmp &&
11893 BuiltinOp != Builtin::BI__builtin_wcscmp) {
11894 APSInt N;
11895 if (!EvaluateInteger(E->getArg(2), N, Info))
11896 return false;
11897 MaxLength = N.getExtValue();
11898 }
11899
11900 // Empty substrings compare equal by definition.
11901 if (MaxLength == 0u)
11902 return Success(0, E);
11903
11904 if (!String1.checkNullPointerForFoldAccess(Info, E, AK_Read) ||
11905 !String2.checkNullPointerForFoldAccess(Info, E, AK_Read) ||
11906 String1.Designator.Invalid || String2.Designator.Invalid)
11907 return false;
11908
11909 QualType CharTy1 = String1.Designator.getType(Info.Ctx);
11910 QualType CharTy2 = String2.Designator.getType(Info.Ctx);
11911
11912 bool IsRawByte = BuiltinOp == Builtin::BImemcmp ||
11913 BuiltinOp == Builtin::BIbcmp ||
11914 BuiltinOp == Builtin::BI__builtin_memcmp ||
11915 BuiltinOp == Builtin::BI__builtin_bcmp;
11916
11917 assert(IsRawByte ||(static_cast <bool> (IsRawByte || (Info.Ctx.hasSameUnqualifiedType
( CharTy1, E->getArg(0)->getType()->getPointeeType()
) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2
))) ? void (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11920, __extension__ __PRETTY_FUNCTION__))
11918 (Info.Ctx.hasSameUnqualifiedType((static_cast <bool> (IsRawByte || (Info.Ctx.hasSameUnqualifiedType
( CharTy1, E->getArg(0)->getType()->getPointeeType()
) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2
))) ? void (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11920, __extension__ __PRETTY_FUNCTION__))
11919 CharTy1, E->getArg(0)->getType()->getPointeeType()) &&(static_cast <bool> (IsRawByte || (Info.Ctx.hasSameUnqualifiedType
( CharTy1, E->getArg(0)->getType()->getPointeeType()
) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2
))) ? void (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11920, __extension__ __PRETTY_FUNCTION__))
11920 Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2)))(static_cast <bool> (IsRawByte || (Info.Ctx.hasSameUnqualifiedType
( CharTy1, E->getArg(0)->getType()->getPointeeType()
) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2
))) ? void (0) : __assert_fail ("IsRawByte || (Info.Ctx.hasSameUnqualifiedType( CharTy1, E->getArg(0)->getType()->getPointeeType()) && Info.Ctx.hasSameUnqualifiedType(CharTy1, CharTy2))"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11920, __extension__ __PRETTY_FUNCTION__))
;
11921
11922 // For memcmp, allow comparing any arrays of '[[un]signed] char' or
11923 // 'char8_t', but no other types.
11924 if (IsRawByte &&
11925 !(isOneByteCharacterType(CharTy1) && isOneByteCharacterType(CharTy2))) {
11926 // FIXME: Consider using our bit_cast implementation to support this.
11927 Info.FFDiag(E, diag::note_constexpr_memcmp_unsupported)
11928 << (std::string("'") + Info.Ctx.BuiltinInfo.getName(BuiltinOp) + "'")
11929 << CharTy1 << CharTy2;
11930 return false;
11931 }
11932
11933 const auto &ReadCurElems = [&](APValue &Char1, APValue &Char2) {
11934 return handleLValueToRValueConversion(Info, E, CharTy1, String1, Char1) &&
11935 handleLValueToRValueConversion(Info, E, CharTy2, String2, Char2) &&
11936 Char1.isInt() && Char2.isInt();
11937 };
11938 const auto &AdvanceElems = [&] {
11939 return HandleLValueArrayAdjustment(Info, E, String1, CharTy1, 1) &&
11940 HandleLValueArrayAdjustment(Info, E, String2, CharTy2, 1);
11941 };
11942
11943 bool StopAtNull =
11944 (BuiltinOp != Builtin::BImemcmp && BuiltinOp != Builtin::BIbcmp &&
11945 BuiltinOp != Builtin::BIwmemcmp &&
11946 BuiltinOp != Builtin::BI__builtin_memcmp &&
11947 BuiltinOp != Builtin::BI__builtin_bcmp &&
11948 BuiltinOp != Builtin::BI__builtin_wmemcmp);
11949 bool IsWide = BuiltinOp == Builtin::BIwcscmp ||
11950 BuiltinOp == Builtin::BIwcsncmp ||
11951 BuiltinOp == Builtin::BIwmemcmp ||
11952 BuiltinOp == Builtin::BI__builtin_wcscmp ||
11953 BuiltinOp == Builtin::BI__builtin_wcsncmp ||
11954 BuiltinOp == Builtin::BI__builtin_wmemcmp;
11955
11956 for (; MaxLength; --MaxLength) {
11957 APValue Char1, Char2;
11958 if (!ReadCurElems(Char1, Char2))
11959 return false;
11960 if (Char1.getInt().ne(Char2.getInt())) {
11961 if (IsWide) // wmemcmp compares with wchar_t signedness.
11962 return Success(Char1.getInt() < Char2.getInt() ? -1 : 1, E);
11963 // memcmp always compares unsigned chars.
11964 return Success(Char1.getInt().ult(Char2.getInt()) ? -1 : 1, E);
11965 }
11966 if (StopAtNull && !Char1.getInt())
11967 return Success(0, E);
11968 assert(!(StopAtNull && !Char2.getInt()))(static_cast <bool> (!(StopAtNull && !Char2.getInt
())) ? void (0) : __assert_fail ("!(StopAtNull && !Char2.getInt())"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 11968, __extension__ __PRETTY_FUNCTION__))
;
11969 if (!AdvanceElems())
11970 return false;
11971 }
11972 // We hit the strncmp / memcmp limit.
11973 return Success(0, E);
11974 }
11975
11976 case Builtin::BI__atomic_always_lock_free:
11977 case Builtin::BI__atomic_is_lock_free:
11978 case Builtin::BI__c11_atomic_is_lock_free: {
11979 APSInt SizeVal;
11980 if (!EvaluateInteger(E->getArg(0), SizeVal, Info))
11981 return false;
11982
11983 // For __atomic_is_lock_free(sizeof(_Atomic(T))), if the size is a power
11984 // of two less than or equal to the maximum inline atomic width, we know it
11985 // is lock-free. If the size isn't a power of two, or greater than the
11986 // maximum alignment where we promote atomics, we know it is not lock-free
11987 // (at least not in the sense of atomic_is_lock_free). Otherwise,
11988 // the answer can only be determined at runtime; for example, 16-byte
11989 // atomics have lock-free implementations on some, but not all,
11990 // x86-64 processors.
11991
11992 // Check power-of-two.
11993 CharUnits Size = CharUnits::fromQuantity(SizeVal.getZExtValue());
11994 if (Size.isPowerOfTwo()) {
11995 // Check against inlining width.
11996 unsigned InlineWidthBits =
11997 Info.Ctx.getTargetInfo().getMaxAtomicInlineWidth();
11998 if (Size <= Info.Ctx.toCharUnitsFromBits(InlineWidthBits)) {
11999 if (BuiltinOp == Builtin::BI__c11_atomic_is_lock_free ||
12000 Size == CharUnits::One() ||
12001 E->getArg(1)->isNullPointerConstant(Info.Ctx,
12002 Expr::NPC_NeverValueDependent))
12003 // OK, we will inline appropriately-aligned operations of this size,
12004 // and _Atomic(T) is appropriately-aligned.
12005 return Success(1, E);
12006
12007 QualType PointeeType = E->getArg(1)->IgnoreImpCasts()->getType()->
12008 castAs<PointerType>()->getPointeeType();
12009 if (!PointeeType->isIncompleteType() &&
12010 Info.Ctx.getTypeAlignInChars(PointeeType) >= Size) {
12011 // OK, we will inline operations on this object.
12012 return Success(1, E);
12013 }
12014 }
12015 }
12016
12017 return BuiltinOp == Builtin::BI__atomic_always_lock_free ?
12018 Success(0, E) : Error(E);
12019 }
12020 case Builtin::BI__builtin_add_overflow:
12021 case Builtin::BI__builtin_sub_overflow:
12022 case Builtin::BI__builtin_mul_overflow:
12023 case Builtin::BI__builtin_sadd_overflow:
12024 case Builtin::BI__builtin_uadd_overflow:
12025 case Builtin::BI__builtin_uaddl_overflow:
12026 case Builtin::BI__builtin_uaddll_overflow:
12027 case Builtin::BI__builtin_usub_overflow:
12028 case Builtin::BI__builtin_usubl_overflow:
12029 case Builtin::BI__builtin_usubll_overflow:
12030 case Builtin::BI__builtin_umul_overflow:
12031 case Builtin::BI__builtin_umull_overflow:
12032 case Builtin::BI__builtin_umulll_overflow:
12033 case Builtin::BI__builtin_saddl_overflow:
12034 case Builtin::BI__builtin_saddll_overflow:
12035 case Builtin::BI__builtin_ssub_overflow:
12036 case Builtin::BI__builtin_ssubl_overflow:
12037 case Builtin::BI__builtin_ssubll_overflow:
12038 case Builtin::BI__builtin_smul_overflow:
12039 case Builtin::BI__builtin_smull_overflow:
12040 case Builtin::BI__builtin_smulll_overflow: {
12041 LValue ResultLValue;
12042 APSInt LHS, RHS;
12043
12044 QualType ResultType = E->getArg(2)->getType()->getPointeeType();
12045 if (!EvaluateInteger(E->getArg(0), LHS, Info) ||
12046 !EvaluateInteger(E->getArg(1), RHS, Info) ||
12047 !EvaluatePointer(E->getArg(2), ResultLValue, Info))
12048 return false;
12049
12050 APSInt Result;
12051 bool DidOverflow = false;
12052
12053 // If the types don't have to match, enlarge all 3 to the largest of them.
12054 if (BuiltinOp == Builtin::BI__builtin_add_overflow ||
12055 BuiltinOp == Builtin::BI__builtin_sub_overflow ||
12056 BuiltinOp == Builtin::BI__builtin_mul_overflow) {
12057 bool IsSigned = LHS.isSigned() || RHS.isSigned() ||
12058 ResultType->isSignedIntegerOrEnumerationType();
12059 bool AllSigned = LHS.isSigned() && RHS.isSigned() &&
12060 ResultType->isSignedIntegerOrEnumerationType();
12061 uint64_t LHSSize = LHS.getBitWidth();
12062 uint64_t RHSSize = RHS.getBitWidth();
12063 uint64_t ResultSize = Info.Ctx.getTypeSize(ResultType);
12064 uint64_t MaxBits = std::max(std::max(LHSSize, RHSSize), ResultSize);
12065
12066 // Add an additional bit if the signedness isn't uniformly agreed to. We
12067 // could do this ONLY if there is a signed and an unsigned that both have
12068 // MaxBits, but the code to check that is pretty nasty. The issue will be
12069 // caught in the shrink-to-result later anyway.
12070 if (IsSigned && !AllSigned)
12071 ++MaxBits;
12072
12073 LHS = APSInt(LHS.extOrTrunc(MaxBits), !IsSigned);
12074 RHS = APSInt(RHS.extOrTrunc(MaxBits), !IsSigned);
12075 Result = APSInt(MaxBits, !IsSigned);
12076 }
12077
12078 // Find largest int.
12079 switch (BuiltinOp) {
12080 default:
12081 llvm_unreachable("Invalid value for BuiltinOp")::llvm::llvm_unreachable_internal("Invalid value for BuiltinOp"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12081)
;
12082 case Builtin::BI__builtin_add_overflow:
12083 case Builtin::BI__builtin_sadd_overflow:
12084 case Builtin::BI__builtin_saddl_overflow:
12085 case Builtin::BI__builtin_saddll_overflow:
12086 case Builtin::BI__builtin_uadd_overflow:
12087 case Builtin::BI__builtin_uaddl_overflow:
12088 case Builtin::BI__builtin_uaddll_overflow:
12089 Result = LHS.isSigned() ? LHS.sadd_ov(RHS, DidOverflow)
12090 : LHS.uadd_ov(RHS, DidOverflow);
12091 break;
12092 case Builtin::BI__builtin_sub_overflow:
12093 case Builtin::BI__builtin_ssub_overflow:
12094 case Builtin::BI__builtin_ssubl_overflow:
12095 case Builtin::BI__builtin_ssubll_overflow:
12096 case Builtin::BI__builtin_usub_overflow:
12097 case Builtin::BI__builtin_usubl_overflow:
12098 case Builtin::BI__builtin_usubll_overflow:
12099 Result = LHS.isSigned() ? LHS.ssub_ov(RHS, DidOverflow)
12100 : LHS.usub_ov(RHS, DidOverflow);
12101 break;
12102 case Builtin::BI__builtin_mul_overflow:
12103 case Builtin::BI__builtin_smul_overflow:
12104 case Builtin::BI__builtin_smull_overflow:
12105 case Builtin::BI__builtin_smulll_overflow:
12106 case Builtin::BI__builtin_umul_overflow:
12107 case Builtin::BI__builtin_umull_overflow:
12108 case Builtin::BI__builtin_umulll_overflow:
12109 Result = LHS.isSigned() ? LHS.smul_ov(RHS, DidOverflow)
12110 : LHS.umul_ov(RHS, DidOverflow);
12111 break;
12112 }
12113
12114 // In the case where multiple sizes are allowed, truncate and see if
12115 // the values are the same.
12116 if (BuiltinOp == Builtin::BI__builtin_add_overflow ||
12117 BuiltinOp == Builtin::BI__builtin_sub_overflow ||
12118 BuiltinOp == Builtin::BI__builtin_mul_overflow) {
12119 // APSInt doesn't have a TruncOrSelf, so we use extOrTrunc instead,
12120 // since it will give us the behavior of a TruncOrSelf in the case where
12121 // its parameter <= its size. We previously set Result to be at least the
12122 // type-size of the result, so getTypeSize(ResultType) <= Result.BitWidth
12123 // will work exactly like TruncOrSelf.
12124 APSInt Temp = Result.extOrTrunc(Info.Ctx.getTypeSize(ResultType));
12125 Temp.setIsSigned(ResultType->isSignedIntegerOrEnumerationType());
12126
12127 if (!APSInt::isSameValue(Temp, Result))
12128 DidOverflow = true;
12129 Result = Temp;
12130 }
12131
12132 APValue APV{Result};
12133 if (!handleAssignment(Info, E, ResultLValue, ResultType, APV))
12134 return false;
12135 return Success(DidOverflow, E);
12136 }
12137 }
12138}
12139
12140/// Determine whether this is a pointer past the end of the complete
12141/// object referred to by the lvalue.
12142static bool isOnePastTheEndOfCompleteObject(const ASTContext &Ctx,
12143 const LValue &LV) {
12144 // A null pointer can be viewed as being "past the end" but we don't
12145 // choose to look at it that way here.
12146 if (!LV.getLValueBase())
12147 return false;
12148
12149 // If the designator is valid and refers to a subobject, we're not pointing
12150 // past the end.
12151 if (!LV.getLValueDesignator().Invalid &&
12152 !LV.getLValueDesignator().isOnePastTheEnd())
12153 return false;
12154
12155 // A pointer to an incomplete type might be past-the-end if the type's size is
12156 // zero. We cannot tell because the type is incomplete.
12157 QualType Ty = getType(LV.getLValueBase());
12158 if (Ty->isIncompleteType())
12159 return true;
12160
12161 // We're a past-the-end pointer if we point to the byte after the object,
12162 // no matter what our type or path is.
12163 auto Size = Ctx.getTypeSizeInChars(Ty);
12164 return LV.getLValueOffset() == Size;
12165}
12166
12167namespace {
12168
12169/// Data recursive integer evaluator of certain binary operators.
12170///
12171/// We use a data recursive algorithm for binary operators so that we are able
12172/// to handle extreme cases of chained binary operators without causing stack
12173/// overflow.
12174class DataRecursiveIntBinOpEvaluator {
12175 struct EvalResult {
12176 APValue Val;
12177 bool Failed;
12178
12179 EvalResult() : Failed(false) { }
12180
12181 void swap(EvalResult &RHS) {
12182 Val.swap(RHS.Val);
12183 Failed = RHS.Failed;
12184 RHS.Failed = false;
12185 }
12186 };
12187
12188 struct Job {
12189 const Expr *E;
12190 EvalResult LHSResult; // meaningful only for binary operator expression.
12191 enum { AnyExprKind, BinOpKind, BinOpVisitedLHSKind } Kind;
12192
12193 Job() = default;
12194 Job(Job &&) = default;
12195
12196 void startSpeculativeEval(EvalInfo &Info) {
12197 SpecEvalRAII = SpeculativeEvaluationRAII(Info);
12198 }
12199
12200 private:
12201 SpeculativeEvaluationRAII SpecEvalRAII;
12202 };
12203
12204 SmallVector<Job, 16> Queue;
12205
12206 IntExprEvaluator &IntEval;
12207 EvalInfo &Info;
12208 APValue &FinalResult;
12209
12210public:
12211 DataRecursiveIntBinOpEvaluator(IntExprEvaluator &IntEval, APValue &Result)
12212 : IntEval(IntEval), Info(IntEval.getEvalInfo()), FinalResult(Result) { }
12213
12214 /// True if \param E is a binary operator that we are going to handle
12215 /// data recursively.
12216 /// We handle binary operators that are comma, logical, or that have operands
12217 /// with integral or enumeration type.
12218 static bool shouldEnqueue(const BinaryOperator *E) {
12219 return E->getOpcode() == BO_Comma || E->isLogicalOp() ||
12220 (E->isPRValue() && E->getType()->isIntegralOrEnumerationType() &&
12221 E->getLHS()->getType()->isIntegralOrEnumerationType() &&
12222 E->getRHS()->getType()->isIntegralOrEnumerationType());
12223 }
12224
12225 bool Traverse(const BinaryOperator *E) {
12226 enqueue(E);
12227 EvalResult PrevResult;
12228 while (!Queue.empty())
12229 process(PrevResult);
12230
12231 if (PrevResult.Failed) return false;
12232
12233 FinalResult.swap(PrevResult.Val);
12234 return true;
12235 }
12236
12237private:
12238 bool Success(uint64_t Value, const Expr *E, APValue &Result) {
12239 return IntEval.Success(Value, E, Result);
12240 }
12241 bool Success(const APSInt &Value, const Expr *E, APValue &Result) {
12242 return IntEval.Success(Value, E, Result);
12243 }
12244 bool Error(const Expr *E) {
12245 return IntEval.Error(E);
12246 }
12247 bool Error(const Expr *E, diag::kind D) {
12248 return IntEval.Error(E, D);
12249 }
12250
12251 OptionalDiagnostic CCEDiag(const Expr *E, diag::kind D) {
12252 return Info.CCEDiag(E, D);
12253 }
12254
12255 // Returns true if visiting the RHS is necessary, false otherwise.
12256 bool VisitBinOpLHSOnly(EvalResult &LHSResult, const BinaryOperator *E,
12257 bool &SuppressRHSDiags);
12258
12259 bool VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult,
12260 const BinaryOperator *E, APValue &Result);
12261
12262 void EvaluateExpr(const Expr *E, EvalResult &Result) {
12263 Result.Failed = !Evaluate(Result.Val, Info, E);
12264 if (Result.Failed)
12265 Result.Val = APValue();
12266 }
12267
12268 void process(EvalResult &Result);
12269
12270 void enqueue(const Expr *E) {
12271 E = E->IgnoreParens();
12272 Queue.resize(Queue.size()+1);
12273 Queue.back().E = E;
12274 Queue.back().Kind = Job::AnyExprKind;
12275 }
12276};
12277
12278}
12279
12280bool DataRecursiveIntBinOpEvaluator::
12281 VisitBinOpLHSOnly(EvalResult &LHSResult, const BinaryOperator *E,
12282 bool &SuppressRHSDiags) {
12283 if (E->getOpcode() == BO_Comma) {
12284 // Ignore LHS but note if we could not evaluate it.
12285 if (LHSResult.Failed)
12286 return Info.noteSideEffect();
12287 return true;
12288 }
12289
12290 if (E->isLogicalOp()) {
12291 bool LHSAsBool;
12292 if (!LHSResult.Failed && HandleConversionToBool(LHSResult.Val, LHSAsBool)) {
12293 // We were able to evaluate the LHS, see if we can get away with not
12294 // evaluating the RHS: 0 && X -> 0, 1 || X -> 1
12295 if (LHSAsBool == (E->getOpcode() == BO_LOr)) {
12296 Success(LHSAsBool, E, LHSResult.Val);
12297 return false; // Ignore RHS
12298 }
12299 } else {
12300 LHSResult.Failed = true;
12301
12302 // Since we weren't able to evaluate the left hand side, it
12303 // might have had side effects.
12304 if (!Info.noteSideEffect())
12305 return false;
12306
12307 // We can't evaluate the LHS; however, sometimes the result
12308 // is determined by the RHS: X && 0 -> 0, X || 1 -> 1.
12309 // Don't ignore RHS and suppress diagnostics from this arm.
12310 SuppressRHSDiags = true;
12311 }
12312
12313 return true;
12314 }
12315
12316 assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType
() && E->getRHS()->getType()->isIntegralOrEnumerationType
()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12317, __extension__ __PRETTY_FUNCTION__))
12317 E->getRHS()->getType()->isIntegralOrEnumerationType())(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType
() && E->getRHS()->getType()->isIntegralOrEnumerationType
()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12317, __extension__ __PRETTY_FUNCTION__))
;
12318
12319 if (LHSResult.Failed && !Info.noteFailure())
12320 return false; // Ignore RHS;
12321
12322 return true;
12323}
12324
12325static void addOrSubLValueAsInteger(APValue &LVal, const APSInt &Index,
12326 bool IsSub) {
12327 // Compute the new offset in the appropriate width, wrapping at 64 bits.
12328 // FIXME: When compiling for a 32-bit target, we should use 32-bit
12329 // offsets.
12330 assert(!LVal.hasLValuePath() && "have designator for integer lvalue")(static_cast <bool> (!LVal.hasLValuePath() && "have designator for integer lvalue"
) ? void (0) : __assert_fail ("!LVal.hasLValuePath() && \"have designator for integer lvalue\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12330, __extension__ __PRETTY_FUNCTION__))
;
12331 CharUnits &Offset = LVal.getLValueOffset();
12332 uint64_t Offset64 = Offset.getQuantity();
12333 uint64_t Index64 = Index.extOrTrunc(64).getZExtValue();
12334 Offset = CharUnits::fromQuantity(IsSub ? Offset64 - Index64
12335 : Offset64 + Index64);
12336}
12337
12338bool DataRecursiveIntBinOpEvaluator::
12339 VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult,
12340 const BinaryOperator *E, APValue &Result) {
12341 if (E->getOpcode() == BO_Comma) {
12342 if (RHSResult.Failed)
12343 return false;
12344 Result = RHSResult.Val;
12345 return true;
12346 }
12347
12348 if (E->isLogicalOp()) {
12349 bool lhsResult, rhsResult;
12350 bool LHSIsOK = HandleConversionToBool(LHSResult.Val, lhsResult);
12351 bool RHSIsOK = HandleConversionToBool(RHSResult.Val, rhsResult);
12352
12353 if (LHSIsOK) {
12354 if (RHSIsOK) {
12355 if (E->getOpcode() == BO_LOr)
12356 return Success(lhsResult || rhsResult, E, Result);
12357 else
12358 return Success(lhsResult && rhsResult, E, Result);
12359 }
12360 } else {
12361 if (RHSIsOK) {
12362 // We can't evaluate the LHS; however, sometimes the result
12363 // is determined by the RHS: X && 0 -> 0, X || 1 -> 1.
12364 if (rhsResult == (E->getOpcode() == BO_LOr))
12365 return Success(rhsResult, E, Result);
12366 }
12367 }
12368
12369 return false;
12370 }
12371
12372 assert(E->getLHS()->getType()->isIntegralOrEnumerationType() &&(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType
() && E->getRHS()->getType()->isIntegralOrEnumerationType
()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12373, __extension__ __PRETTY_FUNCTION__))
12373 E->getRHS()->getType()->isIntegralOrEnumerationType())(static_cast <bool> (E->getLHS()->getType()->isIntegralOrEnumerationType
() && E->getRHS()->getType()->isIntegralOrEnumerationType
()) ? void (0) : __assert_fail ("E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12373, __extension__ __PRETTY_FUNCTION__))
;
12374
12375 if (LHSResult.Failed || RHSResult.Failed)
12376 return false;
12377
12378 const APValue &LHSVal = LHSResult.Val;
12379 const APValue &RHSVal = RHSResult.Val;
12380
12381 // Handle cases like (unsigned long)&a + 4.
12382 if (E->isAdditiveOp() && LHSVal.isLValue() && RHSVal.isInt()) {
12383 Result = LHSVal;
12384 addOrSubLValueAsInteger(Result, RHSVal.getInt(), E->getOpcode() == BO_Sub);
12385 return true;
12386 }
12387
12388 // Handle cases like 4 + (unsigned long)&a
12389 if (E->getOpcode() == BO_Add &&
12390 RHSVal.isLValue() && LHSVal.isInt()) {
12391 Result = RHSVal;
12392 addOrSubLValueAsInteger(Result, LHSVal.getInt(), /*IsSub*/false);
12393 return true;
12394 }
12395
12396 if (E->getOpcode() == BO_Sub && LHSVal.isLValue() && RHSVal.isLValue()) {
12397 // Handle (intptr_t)&&A - (intptr_t)&&B.
12398 if (!LHSVal.getLValueOffset().isZero() ||
12399 !RHSVal.getLValueOffset().isZero())
12400 return false;
12401 const Expr *LHSExpr = LHSVal.getLValueBase().dyn_cast<const Expr*>();
12402 const Expr *RHSExpr = RHSVal.getLValueBase().dyn_cast<const Expr*>();
12403 if (!LHSExpr || !RHSExpr)
12404 return false;
12405 const AddrLabelExpr *LHSAddrExpr = dyn_cast<AddrLabelExpr>(LHSExpr);
12406 const AddrLabelExpr *RHSAddrExpr = dyn_cast<AddrLabelExpr>(RHSExpr);
12407 if (!LHSAddrExpr || !RHSAddrExpr)
12408 return false;
12409 // Make sure both labels come from the same function.
12410 if (LHSAddrExpr->getLabel()->getDeclContext() !=
12411 RHSAddrExpr->getLabel()->getDeclContext())
12412 return false;
12413 Result = APValue(LHSAddrExpr, RHSAddrExpr);
12414 return true;
12415 }
12416
12417 // All the remaining cases expect both operands to be an integer
12418 if (!LHSVal.isInt() || !RHSVal.isInt())
12419 return Error(E);
12420
12421 // Set up the width and signedness manually, in case it can't be deduced
12422 // from the operation we're performing.
12423 // FIXME: Don't do this in the cases where we can deduce it.
12424 APSInt Value(Info.Ctx.getIntWidth(E->getType()),
12425 E->getType()->isUnsignedIntegerOrEnumerationType());
12426 if (!handleIntIntBinOp(Info, E, LHSVal.getInt(), E->getOpcode(),
12427 RHSVal.getInt(), Value))
12428 return false;
12429 return Success(Value, E, Result);
12430}
12431
12432void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) {
12433 Job &job = Queue.back();
12434
12435 switch (job.Kind) {
12436 case Job::AnyExprKind: {
12437 if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(job.E)) {
12438 if (shouldEnqueue(Bop)) {
12439 job.Kind = Job::BinOpKind;
12440 enqueue(Bop->getLHS());
12441 return;
12442 }
12443 }
12444
12445 EvaluateExpr(job.E, Result);
12446 Queue.pop_back();
12447 return;
12448 }
12449
12450 case Job::BinOpKind: {
12451 const BinaryOperator *Bop = cast<BinaryOperator>(job.E);
12452 bool SuppressRHSDiags = false;
12453 if (!VisitBinOpLHSOnly(Result, Bop, SuppressRHSDiags)) {
12454 Queue.pop_back();
12455 return;
12456 }
12457 if (SuppressRHSDiags)
12458 job.startSpeculativeEval(Info);
12459 job.LHSResult.swap(Result);
12460 job.Kind = Job::BinOpVisitedLHSKind;
12461 enqueue(Bop->getRHS());
12462 return;
12463 }
12464
12465 case Job::BinOpVisitedLHSKind: {
12466 const BinaryOperator *Bop = cast<BinaryOperator>(job.E);
12467 EvalResult RHS;
12468 RHS.swap(Result);
12469 Result.Failed = !VisitBinOp(job.LHSResult, RHS, Bop, Result.Val);
12470 Queue.pop_back();
12471 return;
12472 }
12473 }
12474
12475 llvm_unreachable("Invalid Job::Kind!")::llvm::llvm_unreachable_internal("Invalid Job::Kind!", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12475)
;
12476}
12477
12478namespace {
12479enum class CmpResult {
12480 Unequal,
12481 Less,
12482 Equal,
12483 Greater,
12484 Unordered,
12485};
12486}
12487
12488template <class SuccessCB, class AfterCB>
12489static bool
12490EvaluateComparisonBinaryOperator(EvalInfo &Info, const BinaryOperator *E,
12491 SuccessCB &&Success, AfterCB &&DoAfter) {
12492 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12492, __extension__ __PRETTY_FUNCTION__))
;
12493 assert(E->isComparisonOp() && "expected comparison operator")(static_cast <bool> (E->isComparisonOp() && "expected comparison operator"
) ? void (0) : __assert_fail ("E->isComparisonOp() && \"expected comparison operator\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12493, __extension__ __PRETTY_FUNCTION__))
;
12494 assert((E->getOpcode() == BO_Cmp ||(static_cast <bool> ((E->getOpcode() == BO_Cmp || E->
getType()->isIntegralOrEnumerationType()) && "unsupported binary expression evaluation"
) ? void (0) : __assert_fail ("(E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12496, __extension__ __PRETTY_FUNCTION__))
12495 E->getType()->isIntegralOrEnumerationType()) &&(static_cast <bool> ((E->getOpcode() == BO_Cmp || E->
getType()->isIntegralOrEnumerationType()) && "unsupported binary expression evaluation"
) ? void (0) : __assert_fail ("(E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12496, __extension__ __PRETTY_FUNCTION__))
12496 "unsupported binary expression evaluation")(static_cast <bool> ((E->getOpcode() == BO_Cmp || E->
getType()->isIntegralOrEnumerationType()) && "unsupported binary expression evaluation"
) ? void (0) : __assert_fail ("(E->getOpcode() == BO_Cmp || E->getType()->isIntegralOrEnumerationType()) && \"unsupported binary expression evaluation\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12496, __extension__ __PRETTY_FUNCTION__))
;
12497 auto Error = [&](const Expr *E) {
12498 Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
12499 return false;
12500 };
12501
12502 bool IsRelational = E->isRelationalOp() || E->getOpcode() == BO_Cmp;
12503 bool IsEquality = E->isEqualityOp();
12504
12505 QualType LHSTy = E->getLHS()->getType();
12506 QualType RHSTy = E->getRHS()->getType();
12507
12508 if (LHSTy->isIntegralOrEnumerationType() &&
12509 RHSTy->isIntegralOrEnumerationType()) {
12510 APSInt LHS, RHS;
12511 bool LHSOK = EvaluateInteger(E->getLHS(), LHS, Info);
12512 if (!LHSOK && !Info.noteFailure())
12513 return false;
12514 if (!EvaluateInteger(E->getRHS(), RHS, Info) || !LHSOK)
12515 return false;
12516 if (LHS < RHS)
12517 return Success(CmpResult::Less, E);
12518 if (LHS > RHS)
12519 return Success(CmpResult::Greater, E);
12520 return Success(CmpResult::Equal, E);
12521 }
12522
12523 if (LHSTy->isFixedPointType() || RHSTy->isFixedPointType()) {
12524 APFixedPoint LHSFX(Info.Ctx.getFixedPointSemantics(LHSTy));
12525 APFixedPoint RHSFX(Info.Ctx.getFixedPointSemantics(RHSTy));
12526
12527 bool LHSOK = EvaluateFixedPointOrInteger(E->getLHS(), LHSFX, Info);
12528 if (!LHSOK && !Info.noteFailure())
12529 return false;
12530 if (!EvaluateFixedPointOrInteger(E->getRHS(), RHSFX, Info) || !LHSOK)
12531 return false;
12532 if (LHSFX < RHSFX)
12533 return Success(CmpResult::Less, E);
12534 if (LHSFX > RHSFX)
12535 return Success(CmpResult::Greater, E);
12536 return Success(CmpResult::Equal, E);
12537 }
12538
12539 if (LHSTy->isAnyComplexType() || RHSTy->isAnyComplexType()) {
12540 ComplexValue LHS, RHS;
12541 bool LHSOK;
12542 if (E->isAssignmentOp()) {
12543 LValue LV;
12544 EvaluateLValue(E->getLHS(), LV, Info);
12545 LHSOK = false;
12546 } else if (LHSTy->isRealFloatingType()) {
12547 LHSOK = EvaluateFloat(E->getLHS(), LHS.FloatReal, Info);
12548 if (LHSOK) {
12549 LHS.makeComplexFloat();
12550 LHS.FloatImag = APFloat(LHS.FloatReal.getSemantics());
12551 }
12552 } else {
12553 LHSOK = EvaluateComplex(E->getLHS(), LHS, Info);
12554 }
12555 if (!LHSOK && !Info.noteFailure())
12556 return false;
12557
12558 if (E->getRHS()->getType()->isRealFloatingType()) {
12559 if (!EvaluateFloat(E->getRHS(), RHS.FloatReal, Info) || !LHSOK)
12560 return false;
12561 RHS.makeComplexFloat();
12562 RHS.FloatImag = APFloat(RHS.FloatReal.getSemantics());
12563 } else if (!EvaluateComplex(E->getRHS(), RHS, Info) || !LHSOK)
12564 return false;
12565
12566 if (LHS.isComplexFloat()) {
12567 APFloat::cmpResult CR_r =
12568 LHS.getComplexFloatReal().compare(RHS.getComplexFloatReal());
12569 APFloat::cmpResult CR_i =
12570 LHS.getComplexFloatImag().compare(RHS.getComplexFloatImag());
12571 bool IsEqual = CR_r == APFloat::cmpEqual && CR_i == APFloat::cmpEqual;
12572 return Success(IsEqual ? CmpResult::Equal : CmpResult::Unequal, E);
12573 } else {
12574 assert(IsEquality && "invalid complex comparison")(static_cast <bool> (IsEquality && "invalid complex comparison"
) ? void (0) : __assert_fail ("IsEquality && \"invalid complex comparison\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12574, __extension__ __PRETTY_FUNCTION__))
;
12575 bool IsEqual = LHS.getComplexIntReal() == RHS.getComplexIntReal() &&
12576 LHS.getComplexIntImag() == RHS.getComplexIntImag();
12577 return Success(IsEqual ? CmpResult::Equal : CmpResult::Unequal, E);
12578 }
12579 }
12580
12581 if (LHSTy->isRealFloatingType() &&
12582 RHSTy->isRealFloatingType()) {
12583 APFloat RHS(0.0), LHS(0.0);
12584
12585 bool LHSOK = EvaluateFloat(E->getRHS(), RHS, Info);
12586 if (!LHSOK && !Info.noteFailure())
12587 return false;
12588
12589 if (!EvaluateFloat(E->getLHS(), LHS, Info) || !LHSOK)
12590 return false;
12591
12592 assert(E->isComparisonOp() && "Invalid binary operator!")(static_cast <bool> (E->isComparisonOp() && "Invalid binary operator!"
) ? void (0) : __assert_fail ("E->isComparisonOp() && \"Invalid binary operator!\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12592, __extension__ __PRETTY_FUNCTION__))
;
12593 llvm::APFloatBase::cmpResult APFloatCmpResult = LHS.compare(RHS);
12594 if (!Info.InConstantContext &&
12595 APFloatCmpResult == APFloat::cmpUnordered &&
12596 E->getFPFeaturesInEffect(Info.Ctx.getLangOpts()).isFPConstrained()) {
12597 // Note: Compares may raise invalid in some cases involving NaN or sNaN.
12598 Info.FFDiag(E, diag::note_constexpr_float_arithmetic_strict);
12599 return false;
12600 }
12601 auto GetCmpRes = [&]() {
12602 switch (APFloatCmpResult) {
12603 case APFloat::cmpEqual:
12604 return CmpResult::Equal;
12605 case APFloat::cmpLessThan:
12606 return CmpResult::Less;
12607 case APFloat::cmpGreaterThan:
12608 return CmpResult::Greater;
12609 case APFloat::cmpUnordered:
12610 return CmpResult::Unordered;
12611 }
12612 llvm_unreachable("Unrecognised APFloat::cmpResult enum")::llvm::llvm_unreachable_internal("Unrecognised APFloat::cmpResult enum"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12612)
;
12613 };
12614 return Success(GetCmpRes(), E);
12615 }
12616
12617 if (LHSTy->isPointerType() && RHSTy->isPointerType()) {
12618 LValue LHSValue, RHSValue;
12619
12620 bool LHSOK = EvaluatePointer(E->getLHS(), LHSValue, Info);
12621 if (!LHSOK && !Info.noteFailure())
12622 return false;
12623
12624 if (!EvaluatePointer(E->getRHS(), RHSValue, Info) || !LHSOK)
12625 return false;
12626
12627 // Reject differing bases from the normal codepath; we special-case
12628 // comparisons to null.
12629 if (!HasSameBase(LHSValue, RHSValue)) {
12630 // Inequalities and subtractions between unrelated pointers have
12631 // unspecified or undefined behavior.
12632 if (!IsEquality) {
12633 Info.FFDiag(E, diag::note_constexpr_pointer_comparison_unspecified);
12634 return false;
12635 }
12636 // A constant address may compare equal to the address of a symbol.
12637 // The one exception is that address of an object cannot compare equal
12638 // to a null pointer constant.
12639 if ((!LHSValue.Base && !LHSValue.Offset.isZero()) ||
12640 (!RHSValue.Base && !RHSValue.Offset.isZero()))
12641 return Error(E);
12642 // It's implementation-defined whether distinct literals will have
12643 // distinct addresses. In clang, the result of such a comparison is
12644 // unspecified, so it is not a constant expression. However, we do know
12645 // that the address of a literal will be non-null.
12646 if ((IsLiteralLValue(LHSValue) || IsLiteralLValue(RHSValue)) &&
12647 LHSValue.Base && RHSValue.Base)
12648 return Error(E);
12649 // We can't tell whether weak symbols will end up pointing to the same
12650 // object.
12651 if (IsWeakLValue(LHSValue) || IsWeakLValue(RHSValue))
12652 return Error(E);
12653 // We can't compare the address of the start of one object with the
12654 // past-the-end address of another object, per C++ DR1652.
12655 if ((LHSValue.Base && LHSValue.Offset.isZero() &&
12656 isOnePastTheEndOfCompleteObject(Info.Ctx, RHSValue)) ||
12657 (RHSValue.Base && RHSValue.Offset.isZero() &&
12658 isOnePastTheEndOfCompleteObject(Info.Ctx, LHSValue)))
12659 return Error(E);
12660 // We can't tell whether an object is at the same address as another
12661 // zero sized object.
12662 if ((RHSValue.Base && isZeroSized(LHSValue)) ||
12663 (LHSValue.Base && isZeroSized(RHSValue)))
12664 return Error(E);
12665 return Success(CmpResult::Unequal, E);
12666 }
12667
12668 const CharUnits &LHSOffset = LHSValue.getLValueOffset();
12669 const CharUnits &RHSOffset = RHSValue.getLValueOffset();
12670
12671 SubobjectDesignator &LHSDesignator = LHSValue.getLValueDesignator();
12672 SubobjectDesignator &RHSDesignator = RHSValue.getLValueDesignator();
12673
12674 // C++11 [expr.rel]p3:
12675 // Pointers to void (after pointer conversions) can be compared, with a
12676 // result defined as follows: If both pointers represent the same
12677 // address or are both the null pointer value, the result is true if the
12678 // operator is <= or >= and false otherwise; otherwise the result is
12679 // unspecified.
12680 // We interpret this as applying to pointers to *cv* void.
12681 if (LHSTy->isVoidPointerType() && LHSOffset != RHSOffset && IsRelational)
12682 Info.CCEDiag(E, diag::note_constexpr_void_comparison);
12683
12684 // C++11 [expr.rel]p2:
12685 // - If two pointers point to non-static data members of the same object,
12686 // or to subobjects or array elements fo such members, recursively, the
12687 // pointer to the later declared member compares greater provided the
12688 // two members have the same access control and provided their class is
12689 // not a union.
12690 // [...]
12691 // - Otherwise pointer comparisons are unspecified.
12692 if (!LHSDesignator.Invalid && !RHSDesignator.Invalid && IsRelational) {
12693 bool WasArrayIndex;
12694 unsigned Mismatch = FindDesignatorMismatch(
12695 getType(LHSValue.Base), LHSDesignator, RHSDesignator, WasArrayIndex);
12696 // At the point where the designators diverge, the comparison has a
12697 // specified value if:
12698 // - we are comparing array indices
12699 // - we are comparing fields of a union, or fields with the same access
12700 // Otherwise, the result is unspecified and thus the comparison is not a
12701 // constant expression.
12702 if (!WasArrayIndex && Mismatch < LHSDesignator.Entries.size() &&
12703 Mismatch < RHSDesignator.Entries.size()) {
12704 const FieldDecl *LF = getAsField(LHSDesignator.Entries[Mismatch]);
12705 const FieldDecl *RF = getAsField(RHSDesignator.Entries[Mismatch]);
12706 if (!LF && !RF)
12707 Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_classes);
12708 else if (!LF)
12709 Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_field)
12710 << getAsBaseClass(LHSDesignator.Entries[Mismatch])
12711 << RF->getParent() << RF;
12712 else if (!RF)
12713 Info.CCEDiag(E, diag::note_constexpr_pointer_comparison_base_field)
12714 << getAsBaseClass(RHSDesignator.Entries[Mismatch])
12715 << LF->getParent() << LF;
12716 else if (!LF->getParent()->isUnion() &&
12717 LF->getAccess() != RF->getAccess())
12718 Info.CCEDiag(E,
12719 diag::note_constexpr_pointer_comparison_differing_access)
12720 << LF << LF->getAccess() << RF << RF->getAccess()
12721 << LF->getParent();
12722 }
12723 }
12724
12725 // The comparison here must be unsigned, and performed with the same
12726 // width as the pointer.
12727 unsigned PtrSize = Info.Ctx.getTypeSize(LHSTy);
12728 uint64_t CompareLHS = LHSOffset.getQuantity();
12729 uint64_t CompareRHS = RHSOffset.getQuantity();
12730 assert(PtrSize <= 64 && "Unexpected pointer width")(static_cast <bool> (PtrSize <= 64 && "Unexpected pointer width"
) ? void (0) : __assert_fail ("PtrSize <= 64 && \"Unexpected pointer width\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12730, __extension__ __PRETTY_FUNCTION__))
;
12731 uint64_t Mask = ~0ULL >> (64 - PtrSize);
12732 CompareLHS &= Mask;
12733 CompareRHS &= Mask;
12734
12735 // If there is a base and this is a relational operator, we can only
12736 // compare pointers within the object in question; otherwise, the result
12737 // depends on where the object is located in memory.
12738 if (!LHSValue.Base.isNull() && IsRelational) {
12739 QualType BaseTy = getType(LHSValue.Base);
12740 if (BaseTy->isIncompleteType())
12741 return Error(E);
12742 CharUnits Size = Info.Ctx.getTypeSizeInChars(BaseTy);
12743 uint64_t OffsetLimit = Size.getQuantity();
12744 if (CompareLHS > OffsetLimit || CompareRHS > OffsetLimit)
12745 return Error(E);
12746 }
12747
12748 if (CompareLHS < CompareRHS)
12749 return Success(CmpResult::Less, E);
12750 if (CompareLHS > CompareRHS)
12751 return Success(CmpResult::Greater, E);
12752 return Success(CmpResult::Equal, E);
12753 }
12754
12755 if (LHSTy->isMemberPointerType()) {
12756 assert(IsEquality && "unexpected member pointer operation")(static_cast <bool> (IsEquality && "unexpected member pointer operation"
) ? void (0) : __assert_fail ("IsEquality && \"unexpected member pointer operation\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12756, __extension__ __PRETTY_FUNCTION__))
;
12757 assert(RHSTy->isMemberPointerType() && "invalid comparison")(static_cast <bool> (RHSTy->isMemberPointerType() &&
"invalid comparison") ? void (0) : __assert_fail ("RHSTy->isMemberPointerType() && \"invalid comparison\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12757, __extension__ __PRETTY_FUNCTION__))
;
12758
12759 MemberPtr LHSValue, RHSValue;
12760
12761 bool LHSOK = EvaluateMemberPointer(E->getLHS(), LHSValue, Info);
12762 if (!LHSOK && !Info.noteFailure())
12763 return false;
12764
12765 if (!EvaluateMemberPointer(E->getRHS(), RHSValue, Info) || !LHSOK)
12766 return false;
12767
12768 // C++11 [expr.eq]p2:
12769 // If both operands are null, they compare equal. Otherwise if only one is
12770 // null, they compare unequal.
12771 if (!LHSValue.getDecl() || !RHSValue.getDecl()) {
12772 bool Equal = !LHSValue.getDecl() && !RHSValue.getDecl();
12773 return Success(Equal ? CmpResult::Equal : CmpResult::Unequal, E);
12774 }
12775
12776 // Otherwise if either is a pointer to a virtual member function, the
12777 // result is unspecified.
12778 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(LHSValue.getDecl()))
12779 if (MD->isVirtual())
12780 Info.CCEDiag(E, diag::note_constexpr_compare_virtual_mem_ptr) << MD;
12781 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(RHSValue.getDecl()))
12782 if (MD->isVirtual())
12783 Info.CCEDiag(E, diag::note_constexpr_compare_virtual_mem_ptr) << MD;
12784
12785 // Otherwise they compare equal if and only if they would refer to the
12786 // same member of the same most derived object or the same subobject if
12787 // they were dereferenced with a hypothetical object of the associated
12788 // class type.
12789 bool Equal = LHSValue == RHSValue;
12790 return Success(Equal ? CmpResult::Equal : CmpResult::Unequal, E);
12791 }
12792
12793 if (LHSTy->isNullPtrType()) {
12794 assert(E->isComparisonOp() && "unexpected nullptr operation")(static_cast <bool> (E->isComparisonOp() && "unexpected nullptr operation"
) ? void (0) : __assert_fail ("E->isComparisonOp() && \"unexpected nullptr operation\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12794, __extension__ __PRETTY_FUNCTION__))
;
12795 assert(RHSTy->isNullPtrType() && "missing pointer conversion")(static_cast <bool> (RHSTy->isNullPtrType() &&
"missing pointer conversion") ? void (0) : __assert_fail ("RHSTy->isNullPtrType() && \"missing pointer conversion\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12795, __extension__ __PRETTY_FUNCTION__))
;
12796 // C++11 [expr.rel]p4, [expr.eq]p3: If two operands of type std::nullptr_t
12797 // are compared, the result is true of the operator is <=, >= or ==, and
12798 // false otherwise.
12799 return Success(CmpResult::Equal, E);
12800 }
12801
12802 return DoAfter();
12803}
12804
12805bool RecordExprEvaluator::VisitBinCmp(const BinaryOperator *E) {
12806 if (!CheckLiteralType(Info, E))
12807 return false;
12808
12809 auto OnSuccess = [&](CmpResult CR, const BinaryOperator *E) {
12810 ComparisonCategoryResult CCR;
12811 switch (CR) {
12812 case CmpResult::Unequal:
12813 llvm_unreachable("should never produce Unequal for three-way comparison")::llvm::llvm_unreachable_internal("should never produce Unequal for three-way comparison"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12813)
;
12814 case CmpResult::Less:
12815 CCR = ComparisonCategoryResult::Less;
12816 break;
12817 case CmpResult::Equal:
12818 CCR = ComparisonCategoryResult::Equal;
12819 break;
12820 case CmpResult::Greater:
12821 CCR = ComparisonCategoryResult::Greater;
12822 break;
12823 case CmpResult::Unordered:
12824 CCR = ComparisonCategoryResult::Unordered;
12825 break;
12826 }
12827 // Evaluation succeeded. Lookup the information for the comparison category
12828 // type and fetch the VarDecl for the result.
12829 const ComparisonCategoryInfo &CmpInfo =
12830 Info.Ctx.CompCategories.getInfoForType(E->getType());
12831 const VarDecl *VD = CmpInfo.getValueInfo(CmpInfo.makeWeakResult(CCR))->VD;
12832 // Check and evaluate the result as a constant expression.
12833 LValue LV;
12834 LV.set(VD);
12835 if (!handleLValueToRValueConversion(Info, E, E->getType(), LV, Result))
12836 return false;
12837 return CheckConstantExpression(Info, E->getExprLoc(), E->getType(), Result,
12838 ConstantExprKind::Normal);
12839 };
12840 return EvaluateComparisonBinaryOperator(Info, E, OnSuccess, [&]() {
12841 return ExprEvaluatorBaseTy::VisitBinCmp(E);
12842 });
12843}
12844
12845bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
12846 // We don't support assignment in C. C++ assignments don't get here because
12847 // assignment is an lvalue in C++.
12848 if (E->isAssignmentOp()) {
12849 Error(E);
12850 if (!Info.noteFailure())
12851 return false;
12852 }
12853
12854 if (DataRecursiveIntBinOpEvaluator::shouldEnqueue(E))
12855 return DataRecursiveIntBinOpEvaluator(*this, Result).Traverse(E);
12856
12857 assert((!E->getLHS()->getType()->isIntegralOrEnumerationType() ||(static_cast <bool> ((!E->getLHS()->getType()->
isIntegralOrEnumerationType() || !E->getRHS()->getType(
)->isIntegralOrEnumerationType()) && "DataRecursiveIntBinOpEvaluator should have handled integral types"
) ? void (0) : __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() || !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12859, __extension__ __PRETTY_FUNCTION__))
12858 !E->getRHS()->getType()->isIntegralOrEnumerationType()) &&(static_cast <bool> ((!E->getLHS()->getType()->
isIntegralOrEnumerationType() || !E->getRHS()->getType(
)->isIntegralOrEnumerationType()) && "DataRecursiveIntBinOpEvaluator should have handled integral types"
) ? void (0) : __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() || !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12859, __extension__ __PRETTY_FUNCTION__))
12859 "DataRecursiveIntBinOpEvaluator should have handled integral types")(static_cast <bool> ((!E->getLHS()->getType()->
isIntegralOrEnumerationType() || !E->getRHS()->getType(
)->isIntegralOrEnumerationType()) && "DataRecursiveIntBinOpEvaluator should have handled integral types"
) ? void (0) : __assert_fail ("(!E->getLHS()->getType()->isIntegralOrEnumerationType() || !E->getRHS()->getType()->isIntegralOrEnumerationType()) && \"DataRecursiveIntBinOpEvaluator should have handled integral types\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12859, __extension__ __PRETTY_FUNCTION__))
;
12860
12861 if (E->isComparisonOp()) {
12862 // Evaluate builtin binary comparisons by evaluating them as three-way
12863 // comparisons and then translating the result.
12864 auto OnSuccess = [&](CmpResult CR, const BinaryOperator *E) {
12865 assert((CR != CmpResult::Unequal || E->isEqualityOp()) &&(static_cast <bool> ((CR != CmpResult::Unequal || E->
isEqualityOp()) && "should only produce Unequal for equality comparisons"
) ? void (0) : __assert_fail ("(CR != CmpResult::Unequal || E->isEqualityOp()) && \"should only produce Unequal for equality comparisons\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12866, __extension__ __PRETTY_FUNCTION__))
12866 "should only produce Unequal for equality comparisons")(static_cast <bool> ((CR != CmpResult::Unequal || E->
isEqualityOp()) && "should only produce Unequal for equality comparisons"
) ? void (0) : __assert_fail ("(CR != CmpResult::Unequal || E->isEqualityOp()) && \"should only produce Unequal for equality comparisons\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12866, __extension__ __PRETTY_FUNCTION__))
;
12867 bool IsEqual = CR == CmpResult::Equal,
12868 IsLess = CR == CmpResult::Less,
12869 IsGreater = CR == CmpResult::Greater;
12870 auto Op = E->getOpcode();
12871 switch (Op) {
12872 default:
12873 llvm_unreachable("unsupported binary operator")::llvm::llvm_unreachable_internal("unsupported binary operator"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 12873)
;
12874 case BO_EQ:
12875 case BO_NE:
12876 return Success(IsEqual == (Op == BO_EQ), E);
12877 case BO_LT:
12878 return Success(IsLess, E);
12879 case BO_GT:
12880 return Success(IsGreater, E);
12881 case BO_LE:
12882 return Success(IsEqual || IsLess, E);
12883 case BO_GE:
12884 return Success(IsEqual || IsGreater, E);
12885 }
12886 };
12887 return EvaluateComparisonBinaryOperator(Info, E, OnSuccess, [&]() {
12888 return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
12889 });
12890 }
12891
12892 QualType LHSTy = E->getLHS()->getType();
12893 QualType RHSTy = E->getRHS()->getType();
12894
12895 if (LHSTy->isPointerType() && RHSTy->isPointerType() &&
12896 E->getOpcode() == BO_Sub) {
12897 LValue LHSValue, RHSValue;
12898
12899 bool LHSOK = EvaluatePointer(E->getLHS(), LHSValue, Info);
12900 if (!LHSOK && !Info.noteFailure())
12901 return false;
12902
12903 if (!EvaluatePointer(E->getRHS(), RHSValue, Info) || !LHSOK)
12904 return false;
12905
12906 // Reject differing bases from the normal codepath; we special-case
12907 // comparisons to null.
12908 if (!HasSameBase(LHSValue, RHSValue)) {
12909 // Handle &&A - &&B.
12910 if (!LHSValue.Offset.isZero() || !RHSValue.Offset.isZero())
12911 return Error(E);
12912 const Expr *LHSExpr = LHSValue.Base.dyn_cast<const Expr *>();
12913 const Expr *RHSExpr = RHSValue.Base.dyn_cast<const Expr *>();
12914 if (!LHSExpr || !RHSExpr)
12915 return Error(E);
12916 const AddrLabelExpr *LHSAddrExpr = dyn_cast<AddrLabelExpr>(LHSExpr);
12917 const AddrLabelExpr *RHSAddrExpr = dyn_cast<AddrLabelExpr>(RHSExpr);
12918 if (!LHSAddrExpr || !RHSAddrExpr)
12919 return Error(E);
12920 // Make sure both labels come from the same function.
12921 if (LHSAddrExpr->getLabel()->getDeclContext() !=
12922 RHSAddrExpr->getLabel()->getDeclContext())
12923 return Error(E);
12924 return Success(APValue(LHSAddrExpr, RHSAddrExpr), E);
12925 }
12926 const CharUnits &LHSOffset = LHSValue.getLValueOffset();
12927 const CharUnits &RHSOffset = RHSValue.getLValueOffset();
12928
12929 SubobjectDesignator &LHSDesignator = LHSValue.getLValueDesignator();
12930 SubobjectDesignator &RHSDesignator = RHSValue.getLValueDesignator();
12931
12932 // C++11 [expr.add]p6:
12933 // Unless both pointers point to elements of the same array object, or
12934 // one past the last element of the array object, the behavior is
12935 // undefined.
12936 if (!LHSDesignator.Invalid && !RHSDesignator.Invalid &&
12937 !AreElementsOfSameArray(getType(LHSValue.Base), LHSDesignator,
12938 RHSDesignator))
12939 Info.CCEDiag(E, diag::note_constexpr_pointer_subtraction_not_same_array);
12940
12941 QualType Type = E->getLHS()->getType();
12942 QualType ElementType = Type->castAs<PointerType>()->getPointeeType();
12943
12944 CharUnits ElementSize;
12945 if (!HandleSizeof(Info, E->getExprLoc(), ElementType, ElementSize))
12946 return false;
12947
12948 // As an extension, a type may have zero size (empty struct or union in
12949 // C, array of zero length). Pointer subtraction in such cases has
12950 // undefined behavior, so is not constant.
12951 if (ElementSize.isZero()) {
12952 Info.FFDiag(E, diag::note_constexpr_pointer_subtraction_zero_size)
12953 << ElementType;
12954 return false;
12955 }
12956
12957 // FIXME: LLVM and GCC both compute LHSOffset - RHSOffset at runtime,
12958 // and produce incorrect results when it overflows. Such behavior
12959 // appears to be non-conforming, but is common, so perhaps we should
12960 // assume the standard intended for such cases to be undefined behavior
12961 // and check for them.
12962
12963 // Compute (LHSOffset - RHSOffset) / Size carefully, checking for
12964 // overflow in the final conversion to ptrdiff_t.
12965 APSInt LHS(llvm::APInt(65, (int64_t)LHSOffset.getQuantity(), true), false);
12966 APSInt RHS(llvm::APInt(65, (int64_t)RHSOffset.getQuantity(), true), false);
12967 APSInt ElemSize(llvm::APInt(65, (int64_t)ElementSize.getQuantity(), true),
12968 false);
12969 APSInt TrueResult = (LHS - RHS) / ElemSize;
12970 APSInt Result = TrueResult.trunc(Info.Ctx.getIntWidth(E->getType()));
12971
12972 if (Result.extend(65) != TrueResult &&
12973 !HandleOverflow(Info, E, TrueResult, E->getType()))
12974 return false;
12975 return Success(Result, E);
12976 }
12977
12978 return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
12979}
12980
12981/// VisitUnaryExprOrTypeTraitExpr - Evaluate a sizeof, alignof or vec_step with
12982/// a result as the expression's type.
12983bool IntExprEvaluator::VisitUnaryExprOrTypeTraitExpr(
12984 const UnaryExprOrTypeTraitExpr *E) {
12985 switch(E->getKind()) {
12986 case UETT_PreferredAlignOf:
12987 case UETT_AlignOf: {
12988 if (E->isArgumentType())
12989 return Success(GetAlignOfType(Info, E->getArgumentType(), E->getKind()),
12990 E);
12991 else
12992 return Success(GetAlignOfExpr(Info, E->getArgumentExpr(), E->getKind()),
12993 E);
12994 }
12995
12996 case UETT_VecStep: {
12997 QualType Ty = E->getTypeOfArgument();
12998
12999 if (Ty->isVectorType()) {
13000 unsigned n = Ty->castAs<VectorType>()->getNumElements();
13001
13002 // The vec_step built-in functions that take a 3-component
13003 // vector return 4. (OpenCL 1.1 spec 6.11.12)
13004 if (n == 3)
13005 n = 4;
13006
13007 return Success(n, E);
13008 } else
13009 return Success(1, E);
13010 }
13011
13012 case UETT_SizeOf: {
13013 QualType SrcTy = E->getTypeOfArgument();
13014 // C++ [expr.sizeof]p2: "When applied to a reference or a reference type,
13015 // the result is the size of the referenced type."
13016 if (const ReferenceType *Ref = SrcTy->getAs<ReferenceType>())
13017 SrcTy = Ref->getPointeeType();
13018
13019 CharUnits Sizeof;
13020 if (!HandleSizeof(Info, E->getExprLoc(), SrcTy, Sizeof))
13021 return false;
13022 return Success(Sizeof, E);
13023 }
13024 case UETT_OpenMPRequiredSimdAlign:
13025 assert(E->isArgumentType())(static_cast <bool> (E->isArgumentType()) ? void (0)
: __assert_fail ("E->isArgumentType()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13025, __extension__ __PRETTY_FUNCTION__))
;
13026 return Success(
13027 Info.Ctx.toCharUnitsFromBits(
13028 Info.Ctx.getOpenMPDefaultSimdAlign(E->getArgumentType()))
13029 .getQuantity(),
13030 E);
13031 }
13032
13033 llvm_unreachable("unknown expr/type trait")::llvm::llvm_unreachable_internal("unknown expr/type trait", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13033)
;
13034}
13035
13036bool IntExprEvaluator::VisitOffsetOfExpr(const OffsetOfExpr *OOE) {
13037 CharUnits Result;
13038 unsigned n = OOE->getNumComponents();
13039 if (n == 0)
13040 return Error(OOE);
13041 QualType CurrentType = OOE->getTypeSourceInfo()->getType();
13042 for (unsigned i = 0; i != n; ++i) {
13043 OffsetOfNode ON = OOE->getComponent(i);
13044 switch (ON.getKind()) {
13045 case OffsetOfNode::Array: {
13046 const Expr *Idx = OOE->getIndexExpr(ON.getArrayExprIndex());
13047 APSInt IdxResult;
13048 if (!EvaluateInteger(Idx, IdxResult, Info))
13049 return false;
13050 const ArrayType *AT = Info.Ctx.getAsArrayType(CurrentType);
13051 if (!AT)
13052 return Error(OOE);
13053 CurrentType = AT->getElementType();
13054 CharUnits ElementSize = Info.Ctx.getTypeSizeInChars(CurrentType);
13055 Result += IdxResult.getSExtValue() * ElementSize;
13056 break;
13057 }
13058
13059 case OffsetOfNode::Field: {
13060 FieldDecl *MemberDecl = ON.getField();
13061 const RecordType *RT = CurrentType->getAs<RecordType>();
13062 if (!RT)
13063 return Error(OOE);
13064 RecordDecl *RD = RT->getDecl();
13065 if (RD->isInvalidDecl()) return false;
13066 const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD);
13067 unsigned i = MemberDecl->getFieldIndex();
13068 assert(i < RL.getFieldCount() && "offsetof field in wrong type")(static_cast <bool> (i < RL.getFieldCount() &&
"offsetof field in wrong type") ? void (0) : __assert_fail (
"i < RL.getFieldCount() && \"offsetof field in wrong type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13068, __extension__ __PRETTY_FUNCTION__))
;
13069 Result += Info.Ctx.toCharUnitsFromBits(RL.getFieldOffset(i));
13070 CurrentType = MemberDecl->getType().getNonReferenceType();
13071 break;
13072 }
13073
13074 case OffsetOfNode::Identifier:
13075 llvm_unreachable("dependent __builtin_offsetof")::llvm::llvm_unreachable_internal("dependent __builtin_offsetof"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13075)
;
13076
13077 case OffsetOfNode::Base: {
13078 CXXBaseSpecifier *BaseSpec = ON.getBase();
13079 if (BaseSpec->isVirtual())
13080 return Error(OOE);
13081
13082 // Find the layout of the class whose base we are looking into.
13083 const RecordType *RT = CurrentType->getAs<RecordType>();
13084 if (!RT)
13085 return Error(OOE);
13086 RecordDecl *RD = RT->getDecl();
13087 if (RD->isInvalidDecl()) return false;
13088 const ASTRecordLayout &RL = Info.Ctx.getASTRecordLayout(RD);
13089
13090 // Find the base class itself.
13091 CurrentType = BaseSpec->getType();
13092 const RecordType *BaseRT = CurrentType->getAs<RecordType>();
13093 if (!BaseRT)
13094 return Error(OOE);
13095
13096 // Add the offset to the base.
13097 Result += RL.getBaseClassOffset(cast<CXXRecordDecl>(BaseRT->getDecl()));
13098 break;
13099 }
13100 }
13101 }
13102 return Success(Result, OOE);
13103}
13104
13105bool IntExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
13106 switch (E->getOpcode()) {
13107 default:
13108 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs.
13109 // See C99 6.6p3.
13110 return Error(E);
13111 case UO_Extension:
13112 // FIXME: Should extension allow i-c-e extension expressions in its scope?
13113 // If so, we could clear the diagnostic ID.
13114 return Visit(E->getSubExpr());
13115 case UO_Plus:
13116 // The result is just the value.
13117 return Visit(E->getSubExpr());
13118 case UO_Minus: {
13119 if (!Visit(E->getSubExpr()))
13120 return false;
13121 if (!Result.isInt()) return Error(E);
13122 const APSInt &Value = Result.getInt();
13123 if (Value.isSigned() && Value.isMinSignedValue() && E->canOverflow() &&
13124 !HandleOverflow(Info, E, -Value.extend(Value.getBitWidth() + 1),
13125 E->getType()))
13126 return false;
13127 return Success(-Value, E);
13128 }
13129 case UO_Not: {
13130 if (!Visit(E->getSubExpr()))
13131 return false;
13132 if (!Result.isInt()) return Error(E);
13133 return Success(~Result.getInt(), E);
13134 }
13135 case UO_LNot: {
13136 bool bres;
13137 if (!EvaluateAsBooleanCondition(E->getSubExpr(), bres, Info))
13138 return false;
13139 return Success(!bres, E);
13140 }
13141 }
13142}
13143
13144/// HandleCast - This is used to evaluate implicit or explicit casts where the
13145/// result type is integer.
13146bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) {
13147 const Expr *SubExpr = E->getSubExpr();
13148 QualType DestType = E->getType();
13149 QualType SrcType = SubExpr->getType();
13150
13151 switch (E->getCastKind()) {
13152 case CK_BaseToDerived:
13153 case CK_DerivedToBase:
13154 case CK_UncheckedDerivedToBase:
13155 case CK_Dynamic:
13156 case CK_ToUnion:
13157 case CK_ArrayToPointerDecay:
13158 case CK_FunctionToPointerDecay:
13159 case CK_NullToPointer:
13160 case CK_NullToMemberPointer:
13161 case CK_BaseToDerivedMemberPointer:
13162 case CK_DerivedToBaseMemberPointer:
13163 case CK_ReinterpretMemberPointer:
13164 case CK_ConstructorConversion:
13165 case CK_IntegralToPointer:
13166 case CK_ToVoid:
13167 case CK_VectorSplat:
13168 case CK_IntegralToFloating:
13169 case CK_FloatingCast:
13170 case CK_CPointerToObjCPointerCast:
13171 case CK_BlockPointerToObjCPointerCast:
13172 case CK_AnyPointerToBlockPointerCast:
13173 case CK_ObjCObjectLValueCast:
13174 case CK_FloatingRealToComplex:
13175 case CK_FloatingComplexToReal:
13176 case CK_FloatingComplexCast:
13177 case CK_FloatingComplexToIntegralComplex:
13178 case CK_IntegralRealToComplex:
13179 case CK_IntegralComplexCast:
13180 case CK_IntegralComplexToFloatingComplex:
13181 case CK_BuiltinFnToFnPtr:
13182 case CK_ZeroToOCLOpaqueType:
13183 case CK_NonAtomicToAtomic:
13184 case CK_AddressSpaceConversion:
13185 case CK_IntToOCLSampler:
13186 case CK_FloatingToFixedPoint:
13187 case CK_FixedPointToFloating:
13188 case CK_FixedPointCast:
13189 case CK_IntegralToFixedPoint:
13190 case CK_MatrixCast:
13191 llvm_unreachable("invalid cast kind for integral value")::llvm::llvm_unreachable_internal("invalid cast kind for integral value"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13191)
;
13192
13193 case CK_BitCast:
13194 case CK_Dependent:
13195 case CK_LValueBitCast:
13196 case CK_ARCProduceObject:
13197 case CK_ARCConsumeObject:
13198 case CK_ARCReclaimReturnedObject:
13199 case CK_ARCExtendBlockObject:
13200 case CK_CopyAndAutoreleaseBlockObject:
13201 return Error(E);
13202
13203 case CK_UserDefinedConversion:
13204 case CK_LValueToRValue:
13205 case CK_AtomicToNonAtomic:
13206 case CK_NoOp:
13207 case CK_LValueToRValueBitCast:
13208 return ExprEvaluatorBaseTy::VisitCastExpr(E);
13209
13210 case CK_MemberPointerToBoolean:
13211 case CK_PointerToBoolean:
13212 case CK_IntegralToBoolean:
13213 case CK_FloatingToBoolean:
13214 case CK_BooleanToSignedIntegral:
13215 case CK_FloatingComplexToBoolean:
13216 case CK_IntegralComplexToBoolean: {
13217 bool BoolResult;
13218 if (!EvaluateAsBooleanCondition(SubExpr, BoolResult, Info))
13219 return false;
13220 uint64_t IntResult = BoolResult;
13221 if (BoolResult && E->getCastKind() == CK_BooleanToSignedIntegral)
13222 IntResult = (uint64_t)-1;
13223 return Success(IntResult, E);
13224 }
13225
13226 case CK_FixedPointToIntegral: {
13227 APFixedPoint Src(Info.Ctx.getFixedPointSemantics(SrcType));
13228 if (!EvaluateFixedPoint(SubExpr, Src, Info))
13229 return false;
13230 bool Overflowed;
13231 llvm::APSInt Result = Src.convertToInt(
13232 Info.Ctx.getIntWidth(DestType),
13233 DestType->isSignedIntegerOrEnumerationType(), &Overflowed);
13234 if (Overflowed && !HandleOverflow(Info, E, Result, DestType))
13235 return false;
13236 return Success(Result, E);
13237 }
13238
13239 case CK_FixedPointToBoolean: {
13240 // Unsigned padding does not affect this.
13241 APValue Val;
13242 if (!Evaluate(Val, Info, SubExpr))
13243 return false;
13244 return Success(Val.getFixedPoint().getBoolValue(), E);
13245 }
13246
13247 case CK_IntegralCast: {
13248 if (!Visit(SubExpr))
13249 return false;
13250
13251 if (!Result.isInt()) {
13252 // Allow casts of address-of-label differences if they are no-ops
13253 // or narrowing. (The narrowing case isn't actually guaranteed to
13254 // be constant-evaluatable except in some narrow cases which are hard
13255 // to detect here. We let it through on the assumption the user knows
13256 // what they are doing.)
13257 if (Result.isAddrLabelDiff())
13258 return Info.Ctx.getTypeSize(DestType) <= Info.Ctx.getTypeSize(SrcType);
13259 // Only allow casts of lvalues if they are lossless.
13260 return Info.Ctx.getTypeSize(DestType) == Info.Ctx.getTypeSize(SrcType);
13261 }
13262
13263 return Success(HandleIntToIntCast(Info, E, DestType, SrcType,
13264 Result.getInt()), E);
13265 }
13266
13267 case CK_PointerToIntegral: {
13268 CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
13269
13270 LValue LV;
13271 if (!EvaluatePointer(SubExpr, LV, Info))
13272 return false;
13273
13274 if (LV.getLValueBase()) {
13275 // Only allow based lvalue casts if they are lossless.
13276 // FIXME: Allow a larger integer size than the pointer size, and allow
13277 // narrowing back down to pointer width in subsequent integral casts.
13278 // FIXME: Check integer type's active bits, not its type size.
13279 if (Info.Ctx.getTypeSize(DestType) != Info.Ctx.getTypeSize(SrcType))
13280 return Error(E);
13281
13282 LV.Designator.setInvalid();
13283 LV.moveInto(Result);
13284 return true;
13285 }
13286
13287 APSInt AsInt;
13288 APValue V;
13289 LV.moveInto(V);
13290 if (!V.toIntegralConstant(AsInt, SrcType, Info.Ctx))
13291 llvm_unreachable("Can't cast this!")::llvm::llvm_unreachable_internal("Can't cast this!", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13291)
;
13292
13293 return Success(HandleIntToIntCast(Info, E, DestType, SrcType, AsInt), E);
13294 }
13295
13296 case CK_IntegralComplexToReal: {
13297 ComplexValue C;
13298 if (!EvaluateComplex(SubExpr, C, Info))
13299 return false;
13300 return Success(C.getComplexIntReal(), E);
13301 }
13302
13303 case CK_FloatingToIntegral: {
13304 APFloat F(0.0);
13305 if (!EvaluateFloat(SubExpr, F, Info))
13306 return false;
13307
13308 APSInt Value;
13309 if (!HandleFloatToIntCast(Info, E, SrcType, F, DestType, Value))
13310 return false;
13311 return Success(Value, E);
13312 }
13313 }
13314
13315 llvm_unreachable("unknown cast resulting in integral value")::llvm::llvm_unreachable_internal("unknown cast resulting in integral value"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13315)
;
13316}
13317
13318bool IntExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
13319 if (E->getSubExpr()->getType()->isAnyComplexType()) {
13320 ComplexValue LV;
13321 if (!EvaluateComplex(E->getSubExpr(), LV, Info))
13322 return false;
13323 if (!LV.isComplexInt())
13324 return Error(E);
13325 return Success(LV.getComplexIntReal(), E);
13326 }
13327
13328 return Visit(E->getSubExpr());
13329}
13330
13331bool IntExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
13332 if (E->getSubExpr()->getType()->isComplexIntegerType()) {
13333 ComplexValue LV;
13334 if (!EvaluateComplex(E->getSubExpr(), LV, Info))
13335 return false;
13336 if (!LV.isComplexInt())
13337 return Error(E);
13338 return Success(LV.getComplexIntImag(), E);
13339 }
13340
13341 VisitIgnoredValue(E->getSubExpr());
13342 return Success(0, E);
13343}
13344
13345bool IntExprEvaluator::VisitSizeOfPackExpr(const SizeOfPackExpr *E) {
13346 return Success(E->getPackLength(), E);
13347}
13348
13349bool IntExprEvaluator::VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) {
13350 return Success(E->getValue(), E);
13351}
13352
13353bool IntExprEvaluator::VisitConceptSpecializationExpr(
13354 const ConceptSpecializationExpr *E) {
13355 return Success(E->isSatisfied(), E);
13356}
13357
13358bool IntExprEvaluator::VisitRequiresExpr(const RequiresExpr *E) {
13359 return Success(E->isSatisfied(), E);
13360}
13361
13362bool FixedPointExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
13363 switch (E->getOpcode()) {
13364 default:
13365 // Invalid unary operators
13366 return Error(E);
13367 case UO_Plus:
13368 // The result is just the value.
13369 return Visit(E->getSubExpr());
13370 case UO_Minus: {
13371 if (!Visit(E->getSubExpr())) return false;
13372 if (!Result.isFixedPoint())
13373 return Error(E);
13374 bool Overflowed;
13375 APFixedPoint Negated = Result.getFixedPoint().negate(&Overflowed);
13376 if (Overflowed && !HandleOverflow(Info, E, Negated, E->getType()))
13377 return false;
13378 return Success(Negated, E);
13379 }
13380 case UO_LNot: {
13381 bool bres;
13382 if (!EvaluateAsBooleanCondition(E->getSubExpr(), bres, Info))
13383 return false;
13384 return Success(!bres, E);
13385 }
13386 }
13387}
13388
13389bool FixedPointExprEvaluator::VisitCastExpr(const CastExpr *E) {
13390 const Expr *SubExpr = E->getSubExpr();
13391 QualType DestType = E->getType();
13392 assert(DestType->isFixedPointType() &&(static_cast <bool> (DestType->isFixedPointType() &&
"Expected destination type to be a fixed point type") ? void
(0) : __assert_fail ("DestType->isFixedPointType() && \"Expected destination type to be a fixed point type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13393, __extension__ __PRETTY_FUNCTION__))
13393 "Expected destination type to be a fixed point type")(static_cast <bool> (DestType->isFixedPointType() &&
"Expected destination type to be a fixed point type") ? void
(0) : __assert_fail ("DestType->isFixedPointType() && \"Expected destination type to be a fixed point type\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13393, __extension__ __PRETTY_FUNCTION__))
;
13394 auto DestFXSema = Info.Ctx.getFixedPointSemantics(DestType);
13395
13396 switch (E->getCastKind()) {
13397 case CK_FixedPointCast: {
13398 APFixedPoint Src(Info.Ctx.getFixedPointSemantics(SubExpr->getType()));
13399 if (!EvaluateFixedPoint(SubExpr, Src, Info))
13400 return false;
13401 bool Overflowed;
13402 APFixedPoint Result = Src.convert(DestFXSema, &Overflowed);
13403 if (Overflowed) {
13404 if (Info.checkingForUndefinedBehavior())
13405 Info.Ctx.getDiagnostics().Report(E->getExprLoc(),
13406 diag::warn_fixedpoint_constant_overflow)
13407 << Result.toString() << E->getType();
13408 if (!HandleOverflow(Info, E, Result, E->getType()))
13409 return false;
13410 }
13411 return Success(Result, E);
13412 }
13413 case CK_IntegralToFixedPoint: {
13414 APSInt Src;
13415 if (!EvaluateInteger(SubExpr, Src, Info))
13416 return false;
13417
13418 bool Overflowed;
13419 APFixedPoint IntResult = APFixedPoint::getFromIntValue(
13420 Src, Info.Ctx.getFixedPointSemantics(DestType), &Overflowed);
13421
13422 if (Overflowed) {
13423 if (Info.checkingForUndefinedBehavior())
13424 Info.Ctx.getDiagnostics().Report(E->getExprLoc(),
13425 diag::warn_fixedpoint_constant_overflow)
13426 << IntResult.toString() << E->getType();
13427 if (!HandleOverflow(Info, E, IntResult, E->getType()))
13428 return false;
13429 }
13430
13431 return Success(IntResult, E);
13432 }
13433 case CK_FloatingToFixedPoint: {
13434 APFloat Src(0.0);
13435 if (!EvaluateFloat(SubExpr, Src, Info))
13436 return false;
13437
13438 bool Overflowed;
13439 APFixedPoint Result = APFixedPoint::getFromFloatValue(
13440 Src, Info.Ctx.getFixedPointSemantics(DestType), &Overflowed);
13441
13442 if (Overflowed) {
13443 if (Info.checkingForUndefinedBehavior())
13444 Info.Ctx.getDiagnostics().Report(E->getExprLoc(),
13445 diag::warn_fixedpoint_constant_overflow)
13446 << Result.toString() << E->getType();
13447 if (!HandleOverflow(Info, E, Result, E->getType()))
13448 return false;
13449 }
13450
13451 return Success(Result, E);
13452 }
13453 case CK_NoOp:
13454 case CK_LValueToRValue:
13455 return ExprEvaluatorBaseTy::VisitCastExpr(E);
13456 default:
13457 return Error(E);
13458 }
13459}
13460
13461bool FixedPointExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
13462 if (E->isPtrMemOp() || E->isAssignmentOp() || E->getOpcode() == BO_Comma)
13463 return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
13464
13465 const Expr *LHS = E->getLHS();
13466 const Expr *RHS = E->getRHS();
13467 FixedPointSemantics ResultFXSema =
13468 Info.Ctx.getFixedPointSemantics(E->getType());
13469
13470 APFixedPoint LHSFX(Info.Ctx.getFixedPointSemantics(LHS->getType()));
13471 if (!EvaluateFixedPointOrInteger(LHS, LHSFX, Info))
13472 return false;
13473 APFixedPoint RHSFX(Info.Ctx.getFixedPointSemantics(RHS->getType()));
13474 if (!EvaluateFixedPointOrInteger(RHS, RHSFX, Info))
13475 return false;
13476
13477 bool OpOverflow = false, ConversionOverflow = false;
13478 APFixedPoint Result(LHSFX.getSemantics());
13479 switch (E->getOpcode()) {
13480 case BO_Add: {
13481 Result = LHSFX.add(RHSFX, &OpOverflow)
13482 .convert(ResultFXSema, &ConversionOverflow);
13483 break;
13484 }
13485 case BO_Sub: {
13486 Result = LHSFX.sub(RHSFX, &OpOverflow)
13487 .convert(ResultFXSema, &ConversionOverflow);
13488 break;
13489 }
13490 case BO_Mul: {
13491 Result = LHSFX.mul(RHSFX, &OpOverflow)
13492 .convert(ResultFXSema, &ConversionOverflow);
13493 break;
13494 }
13495 case BO_Div: {
13496 if (RHSFX.getValue() == 0) {
13497 Info.FFDiag(E, diag::note_expr_divide_by_zero);
13498 return false;
13499 }
13500 Result = LHSFX.div(RHSFX, &OpOverflow)
13501 .convert(ResultFXSema, &ConversionOverflow);
13502 break;
13503 }
13504 case BO_Shl:
13505 case BO_Shr: {
13506 FixedPointSemantics LHSSema = LHSFX.getSemantics();
13507 llvm::APSInt RHSVal = RHSFX.getValue();
13508
13509 unsigned ShiftBW =
13510 LHSSema.getWidth() - (unsigned)LHSSema.hasUnsignedPadding();
13511 unsigned Amt = RHSVal.getLimitedValue(ShiftBW - 1);
13512 // Embedded-C 4.1.6.2.2:
13513 // The right operand must be nonnegative and less than the total number
13514 // of (nonpadding) bits of the fixed-point operand ...
13515 if (RHSVal.isNegative())
13516 Info.CCEDiag(E, diag::note_constexpr_negative_shift) << RHSVal;
13517 else if (Amt != RHSVal)
13518 Info.CCEDiag(E, diag::note_constexpr_large_shift)
13519 << RHSVal << E->getType() << ShiftBW;
13520
13521 if (E->getOpcode() == BO_Shl)
13522 Result = LHSFX.shl(Amt, &OpOverflow);
13523 else
13524 Result = LHSFX.shr(Amt, &OpOverflow);
13525 break;
13526 }
13527 default:
13528 return false;
13529 }
13530 if (OpOverflow || ConversionOverflow) {
13531 if (Info.checkingForUndefinedBehavior())
13532 Info.Ctx.getDiagnostics().Report(E->getExprLoc(),
13533 diag::warn_fixedpoint_constant_overflow)
13534 << Result.toString() << E->getType();
13535 if (!HandleOverflow(Info, E, Result, E->getType()))
13536 return false;
13537 }
13538 return Success(Result, E);
13539}
13540
13541//===----------------------------------------------------------------------===//
13542// Float Evaluation
13543//===----------------------------------------------------------------------===//
13544
13545namespace {
13546class FloatExprEvaluator
13547 : public ExprEvaluatorBase<FloatExprEvaluator> {
13548 APFloat &Result;
13549public:
13550 FloatExprEvaluator(EvalInfo &info, APFloat &result)
13551 : ExprEvaluatorBaseTy(info), Result(result) {}
13552
13553 bool Success(const APValue &V, const Expr *e) {
13554 Result = V.getFloat();
13555 return true;
13556 }
13557
13558 bool ZeroInitialization(const Expr *E) {
13559 Result = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(E->getType()));
13560 return true;
13561 }
13562
13563 bool VisitCallExpr(const CallExpr *E);
13564
13565 bool VisitUnaryOperator(const UnaryOperator *E);
13566 bool VisitBinaryOperator(const BinaryOperator *E);
13567 bool VisitFloatingLiteral(const FloatingLiteral *E);
13568 bool VisitCastExpr(const CastExpr *E);
13569
13570 bool VisitUnaryReal(const UnaryOperator *E);
13571 bool VisitUnaryImag(const UnaryOperator *E);
13572
13573 // FIXME: Missing: array subscript of vector, member of vector
13574};
13575} // end anonymous namespace
13576
13577static bool EvaluateFloat(const Expr* E, APFloat& Result, EvalInfo &Info) {
13578 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13578, __extension__ __PRETTY_FUNCTION__))
;
13579 assert(E->isPRValue() && E->getType()->isRealFloatingType())(static_cast <bool> (E->isPRValue() && E->
getType()->isRealFloatingType()) ? void (0) : __assert_fail
("E->isPRValue() && E->getType()->isRealFloatingType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13579, __extension__ __PRETTY_FUNCTION__))
;
13580 return FloatExprEvaluator(Info, Result).Visit(E);
13581}
13582
13583static bool TryEvaluateBuiltinNaN(const ASTContext &Context,
13584 QualType ResultTy,
13585 const Expr *Arg,
13586 bool SNaN,
13587 llvm::APFloat &Result) {
13588 const StringLiteral *S = dyn_cast<StringLiteral>(Arg->IgnoreParenCasts());
13589 if (!S) return false;
13590
13591 const llvm::fltSemantics &Sem = Context.getFloatTypeSemantics(ResultTy);
13592
13593 llvm::APInt fill;
13594
13595 // Treat empty strings as if they were zero.
13596 if (S->getString().empty())
13597 fill = llvm::APInt(32, 0);
13598 else if (S->getString().getAsInteger(0, fill))
13599 return false;
13600
13601 if (Context.getTargetInfo().isNan2008()) {
13602 if (SNaN)
13603 Result = llvm::APFloat::getSNaN(Sem, false, &fill);
13604 else
13605 Result = llvm::APFloat::getQNaN(Sem, false, &fill);
13606 } else {
13607 // Prior to IEEE 754-2008, architectures were allowed to choose whether
13608 // the first bit of their significand was set for qNaN or sNaN. MIPS chose
13609 // a different encoding to what became a standard in 2008, and for pre-
13610 // 2008 revisions, MIPS interpreted sNaN-2008 as qNan and qNaN-2008 as
13611 // sNaN. This is now known as "legacy NaN" encoding.
13612 if (SNaN)
13613 Result = llvm::APFloat::getQNaN(Sem, false, &fill);
13614 else
13615 Result = llvm::APFloat::getSNaN(Sem, false, &fill);
13616 }
13617
13618 return true;
13619}
13620
13621bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) {
13622 switch (E->getBuiltinCallee()) {
13623 default:
13624 return ExprEvaluatorBaseTy::VisitCallExpr(E);
13625
13626 case Builtin::BI__builtin_huge_val:
13627 case Builtin::BI__builtin_huge_valf:
13628 case Builtin::BI__builtin_huge_vall:
13629 case Builtin::BI__builtin_huge_valf128:
13630 case Builtin::BI__builtin_inf:
13631 case Builtin::BI__builtin_inff:
13632 case Builtin::BI__builtin_infl:
13633 case Builtin::BI__builtin_inff128: {
13634 const llvm::fltSemantics &Sem =
13635 Info.Ctx.getFloatTypeSemantics(E->getType());
13636 Result = llvm::APFloat::getInf(Sem);
13637 return true;
13638 }
13639
13640 case Builtin::BI__builtin_nans:
13641 case Builtin::BI__builtin_nansf:
13642 case Builtin::BI__builtin_nansl:
13643 case Builtin::BI__builtin_nansf128:
13644 if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0),
13645 true, Result))
13646 return Error(E);
13647 return true;
13648
13649 case Builtin::BI__builtin_nan:
13650 case Builtin::BI__builtin_nanf:
13651 case Builtin::BI__builtin_nanl:
13652 case Builtin::BI__builtin_nanf128:
13653 // If this is __builtin_nan() turn this into a nan, otherwise we
13654 // can't constant fold it.
13655 if (!TryEvaluateBuiltinNaN(Info.Ctx, E->getType(), E->getArg(0),
13656 false, Result))
13657 return Error(E);
13658 return true;
13659
13660 case Builtin::BI__builtin_fabs:
13661 case Builtin::BI__builtin_fabsf:
13662 case Builtin::BI__builtin_fabsl:
13663 case Builtin::BI__builtin_fabsf128:
13664 // The C standard says "fabs raises no floating-point exceptions,
13665 // even if x is a signaling NaN. The returned value is independent of
13666 // the current rounding direction mode." Therefore constant folding can
13667 // proceed without regard to the floating point settings.
13668 // Reference, WG14 N2478 F.10.4.3
13669 if (!EvaluateFloat(E->getArg(0), Result, Info))
13670 return false;
13671
13672 if (Result.isNegative())
13673 Result.changeSign();
13674 return true;
13675
13676 case Builtin::BI__arithmetic_fence:
13677 return EvaluateFloat(E->getArg(0), Result, Info);
13678
13679 // FIXME: Builtin::BI__builtin_powi
13680 // FIXME: Builtin::BI__builtin_powif
13681 // FIXME: Builtin::BI__builtin_powil
13682
13683 case Builtin::BI__builtin_copysign:
13684 case Builtin::BI__builtin_copysignf:
13685 case Builtin::BI__builtin_copysignl:
13686 case Builtin::BI__builtin_copysignf128: {
13687 APFloat RHS(0.);
13688 if (!EvaluateFloat(E->getArg(0), Result, Info) ||
13689 !EvaluateFloat(E->getArg(1), RHS, Info))
13690 return false;
13691 Result.copySign(RHS);
13692 return true;
13693 }
13694 }
13695}
13696
13697bool FloatExprEvaluator::VisitUnaryReal(const UnaryOperator *E) {
13698 if (E->getSubExpr()->getType()->isAnyComplexType()) {
13699 ComplexValue CV;
13700 if (!EvaluateComplex(E->getSubExpr(), CV, Info))
13701 return false;
13702 Result = CV.FloatReal;
13703 return true;
13704 }
13705
13706 return Visit(E->getSubExpr());
13707}
13708
13709bool FloatExprEvaluator::VisitUnaryImag(const UnaryOperator *E) {
13710 if (E->getSubExpr()->getType()->isAnyComplexType()) {
13711 ComplexValue CV;
13712 if (!EvaluateComplex(E->getSubExpr(), CV, Info))
13713 return false;
13714 Result = CV.FloatImag;
13715 return true;
13716 }
13717
13718 VisitIgnoredValue(E->getSubExpr());
13719 const llvm::fltSemantics &Sem = Info.Ctx.getFloatTypeSemantics(E->getType());
13720 Result = llvm::APFloat::getZero(Sem);
13721 return true;
13722}
13723
13724bool FloatExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
13725 switch (E->getOpcode()) {
13726 default: return Error(E);
13727 case UO_Plus:
13728 return EvaluateFloat(E->getSubExpr(), Result, Info);
13729 case UO_Minus:
13730 // In C standard, WG14 N2478 F.3 p4
13731 // "the unary - raises no floating point exceptions,
13732 // even if the operand is signalling."
13733 if (!EvaluateFloat(E->getSubExpr(), Result, Info))
13734 return false;
13735 Result.changeSign();
13736 return true;
13737 }
13738}
13739
13740bool FloatExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
13741 if (E->isPtrMemOp() || E->isAssignmentOp() || E->getOpcode() == BO_Comma)
13742 return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
13743
13744 APFloat RHS(0.0);
13745 bool LHSOK = EvaluateFloat(E->getLHS(), Result, Info);
13746 if (!LHSOK && !Info.noteFailure())
13747 return false;
13748 return EvaluateFloat(E->getRHS(), RHS, Info) && LHSOK &&
13749 handleFloatFloatBinOp(Info, E, Result, E->getOpcode(), RHS);
13750}
13751
13752bool FloatExprEvaluator::VisitFloatingLiteral(const FloatingLiteral *E) {
13753 Result = E->getValue();
13754 return true;
13755}
13756
13757bool FloatExprEvaluator::VisitCastExpr(const CastExpr *E) {
13758 const Expr* SubExpr = E->getSubExpr();
13759
13760 switch (E->getCastKind()) {
13761 default:
13762 return ExprEvaluatorBaseTy::VisitCastExpr(E);
13763
13764 case CK_IntegralToFloating: {
13765 APSInt IntResult;
13766 const FPOptions FPO = E->getFPFeaturesInEffect(
13767 Info.Ctx.getLangOpts());
13768 return EvaluateInteger(SubExpr, IntResult, Info) &&
13769 HandleIntToFloatCast(Info, E, FPO, SubExpr->getType(),
13770 IntResult, E->getType(), Result);
13771 }
13772
13773 case CK_FixedPointToFloating: {
13774 APFixedPoint FixResult(Info.Ctx.getFixedPointSemantics(SubExpr->getType()));
13775 if (!EvaluateFixedPoint(SubExpr, FixResult, Info))
13776 return false;
13777 Result =
13778 FixResult.convertToFloat(Info.Ctx.getFloatTypeSemantics(E->getType()));
13779 return true;
13780 }
13781
13782 case CK_FloatingCast: {
13783 if (!Visit(SubExpr))
13784 return false;
13785 return HandleFloatToFloatCast(Info, E, SubExpr->getType(), E->getType(),
13786 Result);
13787 }
13788
13789 case CK_FloatingComplexToReal: {
13790 ComplexValue V;
13791 if (!EvaluateComplex(SubExpr, V, Info))
13792 return false;
13793 Result = V.getComplexFloatReal();
13794 return true;
13795 }
13796 }
13797}
13798
13799//===----------------------------------------------------------------------===//
13800// Complex Evaluation (for float and integer)
13801//===----------------------------------------------------------------------===//
13802
13803namespace {
13804class ComplexExprEvaluator
13805 : public ExprEvaluatorBase<ComplexExprEvaluator> {
13806 ComplexValue &Result;
13807
13808public:
13809 ComplexExprEvaluator(EvalInfo &info, ComplexValue &Result)
13810 : ExprEvaluatorBaseTy(info), Result(Result) {}
13811
13812 bool Success(const APValue &V, const Expr *e) {
13813 Result.setFrom(V);
13814 return true;
13815 }
13816
13817 bool ZeroInitialization(const Expr *E);
13818
13819 //===--------------------------------------------------------------------===//
13820 // Visitor Methods
13821 //===--------------------------------------------------------------------===//
13822
13823 bool VisitImaginaryLiteral(const ImaginaryLiteral *E);
13824 bool VisitCastExpr(const CastExpr *E);
13825 bool VisitBinaryOperator(const BinaryOperator *E);
13826 bool VisitUnaryOperator(const UnaryOperator *E);
13827 bool VisitInitListExpr(const InitListExpr *E);
13828 bool VisitCallExpr(const CallExpr *E);
13829};
13830} // end anonymous namespace
13831
13832static bool EvaluateComplex(const Expr *E, ComplexValue &Result,
13833 EvalInfo &Info) {
13834 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13834, __extension__ __PRETTY_FUNCTION__))
;
13835 assert(E->isPRValue() && E->getType()->isAnyComplexType())(static_cast <bool> (E->isPRValue() && E->
getType()->isAnyComplexType()) ? void (0) : __assert_fail (
"E->isPRValue() && E->getType()->isAnyComplexType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13835, __extension__ __PRETTY_FUNCTION__))
;
13836 return ComplexExprEvaluator(Info, Result).Visit(E);
13837}
13838
13839bool ComplexExprEvaluator::ZeroInitialization(const Expr *E) {
13840 QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType();
13841 if (ElemTy->isRealFloatingType()) {
13842 Result.makeComplexFloat();
13843 APFloat Zero = APFloat::getZero(Info.Ctx.getFloatTypeSemantics(ElemTy));
13844 Result.FloatReal = Zero;
13845 Result.FloatImag = Zero;
13846 } else {
13847 Result.makeComplexInt();
13848 APSInt Zero = Info.Ctx.MakeIntValue(0, ElemTy);
13849 Result.IntReal = Zero;
13850 Result.IntImag = Zero;
13851 }
13852 return true;
13853}
13854
13855bool ComplexExprEvaluator::VisitImaginaryLiteral(const ImaginaryLiteral *E) {
13856 const Expr* SubExpr = E->getSubExpr();
13857
13858 if (SubExpr->getType()->isRealFloatingType()) {
13859 Result.makeComplexFloat();
13860 APFloat &Imag = Result.FloatImag;
13861 if (!EvaluateFloat(SubExpr, Imag, Info))
13862 return false;
13863
13864 Result.FloatReal = APFloat(Imag.getSemantics());
13865 return true;
13866 } else {
13867 assert(SubExpr->getType()->isIntegerType() &&(static_cast <bool> (SubExpr->getType()->isIntegerType
() && "Unexpected imaginary literal.") ? void (0) : __assert_fail
("SubExpr->getType()->isIntegerType() && \"Unexpected imaginary literal.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13868, __extension__ __PRETTY_FUNCTION__))
13868 "Unexpected imaginary literal.")(static_cast <bool> (SubExpr->getType()->isIntegerType
() && "Unexpected imaginary literal.") ? void (0) : __assert_fail
("SubExpr->getType()->isIntegerType() && \"Unexpected imaginary literal.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13868, __extension__ __PRETTY_FUNCTION__))
;
13869
13870 Result.makeComplexInt();
13871 APSInt &Imag = Result.IntImag;
13872 if (!EvaluateInteger(SubExpr, Imag, Info))
13873 return false;
13874
13875 Result.IntReal = APSInt(Imag.getBitWidth(), !Imag.isSigned());
13876 return true;
13877 }
13878}
13879
13880bool ComplexExprEvaluator::VisitCastExpr(const CastExpr *E) {
13881
13882 switch (E->getCastKind()) {
13883 case CK_BitCast:
13884 case CK_BaseToDerived:
13885 case CK_DerivedToBase:
13886 case CK_UncheckedDerivedToBase:
13887 case CK_Dynamic:
13888 case CK_ToUnion:
13889 case CK_ArrayToPointerDecay:
13890 case CK_FunctionToPointerDecay:
13891 case CK_NullToPointer:
13892 case CK_NullToMemberPointer:
13893 case CK_BaseToDerivedMemberPointer:
13894 case CK_DerivedToBaseMemberPointer:
13895 case CK_MemberPointerToBoolean:
13896 case CK_ReinterpretMemberPointer:
13897 case CK_ConstructorConversion:
13898 case CK_IntegralToPointer:
13899 case CK_PointerToIntegral:
13900 case CK_PointerToBoolean:
13901 case CK_ToVoid:
13902 case CK_VectorSplat:
13903 case CK_IntegralCast:
13904 case CK_BooleanToSignedIntegral:
13905 case CK_IntegralToBoolean:
13906 case CK_IntegralToFloating:
13907 case CK_FloatingToIntegral:
13908 case CK_FloatingToBoolean:
13909 case CK_FloatingCast:
13910 case CK_CPointerToObjCPointerCast:
13911 case CK_BlockPointerToObjCPointerCast:
13912 case CK_AnyPointerToBlockPointerCast:
13913 case CK_ObjCObjectLValueCast:
13914 case CK_FloatingComplexToReal:
13915 case CK_FloatingComplexToBoolean:
13916 case CK_IntegralComplexToReal:
13917 case CK_IntegralComplexToBoolean:
13918 case CK_ARCProduceObject:
13919 case CK_ARCConsumeObject:
13920 case CK_ARCReclaimReturnedObject:
13921 case CK_ARCExtendBlockObject:
13922 case CK_CopyAndAutoreleaseBlockObject:
13923 case CK_BuiltinFnToFnPtr:
13924 case CK_ZeroToOCLOpaqueType:
13925 case CK_NonAtomicToAtomic:
13926 case CK_AddressSpaceConversion:
13927 case CK_IntToOCLSampler:
13928 case CK_FloatingToFixedPoint:
13929 case CK_FixedPointToFloating:
13930 case CK_FixedPointCast:
13931 case CK_FixedPointToBoolean:
13932 case CK_FixedPointToIntegral:
13933 case CK_IntegralToFixedPoint:
13934 case CK_MatrixCast:
13935 llvm_unreachable("invalid cast kind for complex value")::llvm::llvm_unreachable_internal("invalid cast kind for complex value"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 13935)
;
13936
13937 case CK_LValueToRValue:
13938 case CK_AtomicToNonAtomic:
13939 case CK_NoOp:
13940 case CK_LValueToRValueBitCast:
13941 return ExprEvaluatorBaseTy::VisitCastExpr(E);
13942
13943 case CK_Dependent:
13944 case CK_LValueBitCast:
13945 case CK_UserDefinedConversion:
13946 return Error(E);
13947
13948 case CK_FloatingRealToComplex: {
13949 APFloat &Real = Result.FloatReal;
13950 if (!EvaluateFloat(E->getSubExpr(), Real, Info))
13951 return false;
13952
13953 Result.makeComplexFloat();
13954 Result.FloatImag = APFloat(Real.getSemantics());
13955 return true;
13956 }
13957
13958 case CK_FloatingComplexCast: {
13959 if (!Visit(E->getSubExpr()))
13960 return false;
13961
13962 QualType To = E->getType()->castAs<ComplexType>()->getElementType();
13963 QualType From
13964 = E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType();
13965
13966 return HandleFloatToFloatCast(Info, E, From, To, Result.FloatReal) &&
13967 HandleFloatToFloatCast(Info, E, From, To, Result.FloatImag);
13968 }
13969
13970 case CK_FloatingComplexToIntegralComplex: {
13971 if (!Visit(E->getSubExpr()))
13972 return false;
13973
13974 QualType To = E->getType()->castAs<ComplexType>()->getElementType();
13975 QualType From
13976 = E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType();
13977 Result.makeComplexInt();
13978 return HandleFloatToIntCast(Info, E, From, Result.FloatReal,
13979 To, Result.IntReal) &&
13980 HandleFloatToIntCast(Info, E, From, Result.FloatImag,
13981 To, Result.IntImag);
13982 }
13983
13984 case CK_IntegralRealToComplex: {
13985 APSInt &Real = Result.IntReal;
13986 if (!EvaluateInteger(E->getSubExpr(), Real, Info))
13987 return false;
13988
13989 Result.makeComplexInt();
13990 Result.IntImag = APSInt(Real.getBitWidth(), !Real.isSigned());
13991 return true;
13992 }
13993
13994 case CK_IntegralComplexCast: {
13995 if (!Visit(E->getSubExpr()))
13996 return false;
13997
13998 QualType To = E->getType()->castAs<ComplexType>()->getElementType();
13999 QualType From
14000 = E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType();
14001
14002 Result.IntReal = HandleIntToIntCast(Info, E, To, From, Result.IntReal);
14003 Result.IntImag = HandleIntToIntCast(Info, E, To, From, Result.IntImag);
14004 return true;
14005 }
14006
14007 case CK_IntegralComplexToFloatingComplex: {
14008 if (!Visit(E->getSubExpr()))
14009 return false;
14010
14011 const FPOptions FPO = E->getFPFeaturesInEffect(
14012 Info.Ctx.getLangOpts());
14013 QualType To = E->getType()->castAs<ComplexType>()->getElementType();
14014 QualType From
14015 = E->getSubExpr()->getType()->castAs<ComplexType>()->getElementType();
14016 Result.makeComplexFloat();
14017 return HandleIntToFloatCast(Info, E, FPO, From, Result.IntReal,
14018 To, Result.FloatReal) &&
14019 HandleIntToFloatCast(Info, E, FPO, From, Result.IntImag,
14020 To, Result.FloatImag);
14021 }
14022 }
14023
14024 llvm_unreachable("unknown cast resulting in complex value")::llvm::llvm_unreachable_internal("unknown cast resulting in complex value"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14024)
;
14025}
14026
14027bool ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
14028 if (E->isPtrMemOp() || E->isAssignmentOp() || E->getOpcode() == BO_Comma)
14029 return ExprEvaluatorBaseTy::VisitBinaryOperator(E);
14030
14031 // Track whether the LHS or RHS is real at the type system level. When this is
14032 // the case we can simplify our evaluation strategy.
14033 bool LHSReal = false, RHSReal = false;
14034
14035 bool LHSOK;
14036 if (E->getLHS()->getType()->isRealFloatingType()) {
14037 LHSReal = true;
14038 APFloat &Real = Result.FloatReal;
14039 LHSOK = EvaluateFloat(E->getLHS(), Real, Info);
14040 if (LHSOK) {
14041 Result.makeComplexFloat();
14042 Result.FloatImag = APFloat(Real.getSemantics());
14043 }
14044 } else {
14045 LHSOK = Visit(E->getLHS());
14046 }
14047 if (!LHSOK && !Info.noteFailure())
14048 return false;
14049
14050 ComplexValue RHS;
14051 if (E->getRHS()->getType()->isRealFloatingType()) {
14052 RHSReal = true;
14053 APFloat &Real = RHS.FloatReal;
14054 if (!EvaluateFloat(E->getRHS(), Real, Info) || !LHSOK)
14055 return false;
14056 RHS.makeComplexFloat();
14057 RHS.FloatImag = APFloat(Real.getSemantics());
14058 } else if (!EvaluateComplex(E->getRHS(), RHS, Info) || !LHSOK)
14059 return false;
14060
14061 assert(!(LHSReal && RHSReal) &&(static_cast <bool> (!(LHSReal && RHSReal) &&
"Cannot have both operands of a complex operation be real.")
? void (0) : __assert_fail ("!(LHSReal && RHSReal) && \"Cannot have both operands of a complex operation be real.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14062, __extension__ __PRETTY_FUNCTION__))
14062 "Cannot have both operands of a complex operation be real.")(static_cast <bool> (!(LHSReal && RHSReal) &&
"Cannot have both operands of a complex operation be real.")
? void (0) : __assert_fail ("!(LHSReal && RHSReal) && \"Cannot have both operands of a complex operation be real.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14062, __extension__ __PRETTY_FUNCTION__))
;
14063 switch (E->getOpcode()) {
14064 default: return Error(E);
14065 case BO_Add:
14066 if (Result.isComplexFloat()) {
14067 Result.getComplexFloatReal().add(RHS.getComplexFloatReal(),
14068 APFloat::rmNearestTiesToEven);
14069 if (LHSReal)
14070 Result.getComplexFloatImag() = RHS.getComplexFloatImag();
14071 else if (!RHSReal)
14072 Result.getComplexFloatImag().add(RHS.getComplexFloatImag(),
14073 APFloat::rmNearestTiesToEven);
14074 } else {
14075 Result.getComplexIntReal() += RHS.getComplexIntReal();
14076 Result.getComplexIntImag() += RHS.getComplexIntImag();
14077 }
14078 break;
14079 case BO_Sub:
14080 if (Result.isComplexFloat()) {
14081 Result.getComplexFloatReal().subtract(RHS.getComplexFloatReal(),
14082 APFloat::rmNearestTiesToEven);
14083 if (LHSReal) {
14084 Result.getComplexFloatImag() = RHS.getComplexFloatImag();
14085 Result.getComplexFloatImag().changeSign();
14086 } else if (!RHSReal) {
14087 Result.getComplexFloatImag().subtract(RHS.getComplexFloatImag(),
14088 APFloat::rmNearestTiesToEven);
14089 }
14090 } else {
14091 Result.getComplexIntReal() -= RHS.getComplexIntReal();
14092 Result.getComplexIntImag() -= RHS.getComplexIntImag();
14093 }
14094 break;
14095 case BO_Mul:
14096 if (Result.isComplexFloat()) {
14097 // This is an implementation of complex multiplication according to the
14098 // constraints laid out in C11 Annex G. The implementation uses the
14099 // following naming scheme:
14100 // (a + ib) * (c + id)
14101 ComplexValue LHS = Result;
14102 APFloat &A = LHS.getComplexFloatReal();
14103 APFloat &B = LHS.getComplexFloatImag();
14104 APFloat &C = RHS.getComplexFloatReal();
14105 APFloat &D = RHS.getComplexFloatImag();
14106 APFloat &ResR = Result.getComplexFloatReal();
14107 APFloat &ResI = Result.getComplexFloatImag();
14108 if (LHSReal) {
14109 assert(!RHSReal && "Cannot have two real operands for a complex op!")(static_cast <bool> (!RHSReal && "Cannot have two real operands for a complex op!"
) ? void (0) : __assert_fail ("!RHSReal && \"Cannot have two real operands for a complex op!\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14109, __extension__ __PRETTY_FUNCTION__))
;
14110 ResR = A * C;
14111 ResI = A * D;
14112 } else if (RHSReal) {
14113 ResR = C * A;
14114 ResI = C * B;
14115 } else {
14116 // In the fully general case, we need to handle NaNs and infinities
14117 // robustly.
14118 APFloat AC = A * C;
14119 APFloat BD = B * D;
14120 APFloat AD = A * D;
14121 APFloat BC = B * C;
14122 ResR = AC - BD;
14123 ResI = AD + BC;
14124 if (ResR.isNaN() && ResI.isNaN()) {
14125 bool Recalc = false;
14126 if (A.isInfinity() || B.isInfinity()) {
14127 A = APFloat::copySign(
14128 APFloat(A.getSemantics(), A.isInfinity() ? 1 : 0), A);
14129 B = APFloat::copySign(
14130 APFloat(B.getSemantics(), B.isInfinity() ? 1 : 0), B);
14131 if (C.isNaN())
14132 C = APFloat::copySign(APFloat(C.getSemantics()), C);
14133 if (D.isNaN())
14134 D = APFloat::copySign(APFloat(D.getSemantics()), D);
14135 Recalc = true;
14136 }
14137 if (C.isInfinity() || D.isInfinity()) {
14138 C = APFloat::copySign(
14139 APFloat(C.getSemantics(), C.isInfinity() ? 1 : 0), C);
14140 D = APFloat::copySign(
14141 APFloat(D.getSemantics(), D.isInfinity() ? 1 : 0), D);
14142 if (A.isNaN())
14143 A = APFloat::copySign(APFloat(A.getSemantics()), A);
14144 if (B.isNaN())
14145 B = APFloat::copySign(APFloat(B.getSemantics()), B);
14146 Recalc = true;
14147 }
14148 if (!Recalc && (AC.isInfinity() || BD.isInfinity() ||
14149 AD.isInfinity() || BC.isInfinity())) {
14150 if (A.isNaN())
14151 A = APFloat::copySign(APFloat(A.getSemantics()), A);
14152 if (B.isNaN())
14153 B = APFloat::copySign(APFloat(B.getSemantics()), B);
14154 if (C.isNaN())
14155 C = APFloat::copySign(APFloat(C.getSemantics()), C);
14156 if (D.isNaN())
14157 D = APFloat::copySign(APFloat(D.getSemantics()), D);
14158 Recalc = true;
14159 }
14160 if (Recalc) {
14161 ResR = APFloat::getInf(A.getSemantics()) * (A * C - B * D);
14162 ResI = APFloat::getInf(A.getSemantics()) * (A * D + B * C);
14163 }
14164 }
14165 }
14166 } else {
14167 ComplexValue LHS = Result;
14168 Result.getComplexIntReal() =
14169 (LHS.getComplexIntReal() * RHS.getComplexIntReal() -
14170 LHS.getComplexIntImag() * RHS.getComplexIntImag());
14171 Result.getComplexIntImag() =
14172 (LHS.getComplexIntReal() * RHS.getComplexIntImag() +
14173 LHS.getComplexIntImag() * RHS.getComplexIntReal());
14174 }
14175 break;
14176 case BO_Div:
14177 if (Result.isComplexFloat()) {
14178 // This is an implementation of complex division according to the
14179 // constraints laid out in C11 Annex G. The implementation uses the
14180 // following naming scheme:
14181 // (a + ib) / (c + id)
14182 ComplexValue LHS = Result;
14183 APFloat &A = LHS.getComplexFloatReal();
14184 APFloat &B = LHS.getComplexFloatImag();
14185 APFloat &C = RHS.getComplexFloatReal();
14186 APFloat &D = RHS.getComplexFloatImag();
14187 APFloat &ResR = Result.getComplexFloatReal();
14188 APFloat &ResI = Result.getComplexFloatImag();
14189 if (RHSReal) {
14190 ResR = A / C;
14191 ResI = B / C;
14192 } else {
14193 if (LHSReal) {
14194 // No real optimizations we can do here, stub out with zero.
14195 B = APFloat::getZero(A.getSemantics());
14196 }
14197 int DenomLogB = 0;
14198 APFloat MaxCD = maxnum(abs(C), abs(D));
14199 if (MaxCD.isFinite()) {
14200 DenomLogB = ilogb(MaxCD);
14201 C = scalbn(C, -DenomLogB, APFloat::rmNearestTiesToEven);
14202 D = scalbn(D, -DenomLogB, APFloat::rmNearestTiesToEven);
14203 }
14204 APFloat Denom = C * C + D * D;
14205 ResR = scalbn((A * C + B * D) / Denom, -DenomLogB,
14206 APFloat::rmNearestTiesToEven);
14207 ResI = scalbn((B * C - A * D) / Denom, -DenomLogB,
14208 APFloat::rmNearestTiesToEven);
14209 if (ResR.isNaN() && ResI.isNaN()) {
14210 if (Denom.isPosZero() && (!A.isNaN() || !B.isNaN())) {
14211 ResR = APFloat::getInf(ResR.getSemantics(), C.isNegative()) * A;
14212 ResI = APFloat::getInf(ResR.getSemantics(), C.isNegative()) * B;
14213 } else if ((A.isInfinity() || B.isInfinity()) && C.isFinite() &&
14214 D.isFinite()) {
14215 A = APFloat::copySign(
14216 APFloat(A.getSemantics(), A.isInfinity() ? 1 : 0), A);
14217 B = APFloat::copySign(
14218 APFloat(B.getSemantics(), B.isInfinity() ? 1 : 0), B);
14219 ResR = APFloat::getInf(ResR.getSemantics()) * (A * C + B * D);
14220 ResI = APFloat::getInf(ResI.getSemantics()) * (B * C - A * D);
14221 } else if (MaxCD.isInfinity() && A.isFinite() && B.isFinite()) {
14222 C = APFloat::copySign(
14223 APFloat(C.getSemantics(), C.isInfinity() ? 1 : 0), C);
14224 D = APFloat::copySign(
14225 APFloat(D.getSemantics(), D.isInfinity() ? 1 : 0), D);
14226 ResR = APFloat::getZero(ResR.getSemantics()) * (A * C + B * D);
14227 ResI = APFloat::getZero(ResI.getSemantics()) * (B * C - A * D);
14228 }
14229 }
14230 }
14231 } else {
14232 if (RHS.getComplexIntReal() == 0 && RHS.getComplexIntImag() == 0)
14233 return Error(E, diag::note_expr_divide_by_zero);
14234
14235 ComplexValue LHS = Result;
14236 APSInt Den = RHS.getComplexIntReal() * RHS.getComplexIntReal() +
14237 RHS.getComplexIntImag() * RHS.getComplexIntImag();
14238 Result.getComplexIntReal() =
14239 (LHS.getComplexIntReal() * RHS.getComplexIntReal() +
14240 LHS.getComplexIntImag() * RHS.getComplexIntImag()) / Den;
14241 Result.getComplexIntImag() =
14242 (LHS.getComplexIntImag() * RHS.getComplexIntReal() -
14243 LHS.getComplexIntReal() * RHS.getComplexIntImag()) / Den;
14244 }
14245 break;
14246 }
14247
14248 return true;
14249}
14250
14251bool ComplexExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) {
14252 // Get the operand value into 'Result'.
14253 if (!Visit(E->getSubExpr()))
14254 return false;
14255
14256 switch (E->getOpcode()) {
14257 default:
14258 return Error(E);
14259 case UO_Extension:
14260 return true;
14261 case UO_Plus:
14262 // The result is always just the subexpr.
14263 return true;
14264 case UO_Minus:
14265 if (Result.isComplexFloat()) {
14266 Result.getComplexFloatReal().changeSign();
14267 Result.getComplexFloatImag().changeSign();
14268 }
14269 else {
14270 Result.getComplexIntReal() = -Result.getComplexIntReal();
14271 Result.getComplexIntImag() = -Result.getComplexIntImag();
14272 }
14273 return true;
14274 case UO_Not:
14275 if (Result.isComplexFloat())
14276 Result.getComplexFloatImag().changeSign();
14277 else
14278 Result.getComplexIntImag() = -Result.getComplexIntImag();
14279 return true;
14280 }
14281}
14282
14283bool ComplexExprEvaluator::VisitInitListExpr(const InitListExpr *E) {
14284 if (E->getNumInits() == 2) {
14285 if (E->getType()->isComplexType()) {
14286 Result.makeComplexFloat();
14287 if (!EvaluateFloat(E->getInit(0), Result.FloatReal, Info))
14288 return false;
14289 if (!EvaluateFloat(E->getInit(1), Result.FloatImag, Info))
14290 return false;
14291 } else {
14292 Result.makeComplexInt();
14293 if (!EvaluateInteger(E->getInit(0), Result.IntReal, Info))
14294 return false;
14295 if (!EvaluateInteger(E->getInit(1), Result.IntImag, Info))
14296 return false;
14297 }
14298 return true;
14299 }
14300 return ExprEvaluatorBaseTy::VisitInitListExpr(E);
14301}
14302
14303bool ComplexExprEvaluator::VisitCallExpr(const CallExpr *E) {
14304 switch (E->getBuiltinCallee()) {
14305 case Builtin::BI__builtin_complex:
14306 Result.makeComplexFloat();
14307 if (!EvaluateFloat(E->getArg(0), Result.FloatReal, Info))
14308 return false;
14309 if (!EvaluateFloat(E->getArg(1), Result.FloatImag, Info))
14310 return false;
14311 return true;
14312
14313 default:
14314 break;
14315 }
14316
14317 return ExprEvaluatorBaseTy::VisitCallExpr(E);
14318}
14319
14320//===----------------------------------------------------------------------===//
14321// Atomic expression evaluation, essentially just handling the NonAtomicToAtomic
14322// implicit conversion.
14323//===----------------------------------------------------------------------===//
14324
14325namespace {
14326class AtomicExprEvaluator :
14327 public ExprEvaluatorBase<AtomicExprEvaluator> {
14328 const LValue *This;
14329 APValue &Result;
14330public:
14331 AtomicExprEvaluator(EvalInfo &Info, const LValue *This, APValue &Result)
14332 : ExprEvaluatorBaseTy(Info), This(This), Result(Result) {}
14333
14334 bool Success(const APValue &V, const Expr *E) {
14335 Result = V;
14336 return true;
14337 }
14338
14339 bool ZeroInitialization(const Expr *E) {
14340 ImplicitValueInitExpr VIE(
14341 E->getType()->castAs<AtomicType>()->getValueType());
14342 // For atomic-qualified class (and array) types in C++, initialize the
14343 // _Atomic-wrapped subobject directly, in-place.
14344 return This ? EvaluateInPlace(Result, Info, *This, &VIE)
14345 : Evaluate(Result, Info, &VIE);
14346 }
14347
14348 bool VisitCastExpr(const CastExpr *E) {
14349 switch (E->getCastKind()) {
14350 default:
14351 return ExprEvaluatorBaseTy::VisitCastExpr(E);
14352 case CK_NonAtomicToAtomic:
14353 return This ? EvaluateInPlace(Result, Info, *This, E->getSubExpr())
14354 : Evaluate(Result, Info, E->getSubExpr());
14355 }
14356 }
14357};
14358} // end anonymous namespace
14359
14360static bool EvaluateAtomic(const Expr *E, const LValue *This, APValue &Result,
14361 EvalInfo &Info) {
14362 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14362, __extension__ __PRETTY_FUNCTION__))
;
14363 assert(E->isPRValue() && E->getType()->isAtomicType())(static_cast <bool> (E->isPRValue() && E->
getType()->isAtomicType()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isAtomicType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14363, __extension__ __PRETTY_FUNCTION__))
;
14364 return AtomicExprEvaluator(Info, This, Result).Visit(E);
14365}
14366
14367//===----------------------------------------------------------------------===//
14368// Void expression evaluation, primarily for a cast to void on the LHS of a
14369// comma operator
14370//===----------------------------------------------------------------------===//
14371
14372namespace {
14373class VoidExprEvaluator
14374 : public ExprEvaluatorBase<VoidExprEvaluator> {
14375public:
14376 VoidExprEvaluator(EvalInfo &Info) : ExprEvaluatorBaseTy(Info) {}
14377
14378 bool Success(const APValue &V, const Expr *e) { return true; }
14379
14380 bool ZeroInitialization(const Expr *E) { return true; }
14381
14382 bool VisitCastExpr(const CastExpr *E) {
14383 switch (E->getCastKind()) {
14384 default:
14385 return ExprEvaluatorBaseTy::VisitCastExpr(E);
14386 case CK_ToVoid:
14387 VisitIgnoredValue(E->getSubExpr());
14388 return true;
14389 }
14390 }
14391
14392 bool VisitCallExpr(const CallExpr *E) {
14393 switch (E->getBuiltinCallee()) {
14394 case Builtin::BI__assume:
14395 case Builtin::BI__builtin_assume:
14396 // The argument is not evaluated!
14397 return true;
14398
14399 case Builtin::BI__builtin_operator_delete:
14400 return HandleOperatorDeleteCall(Info, E);
14401
14402 default:
14403 break;
14404 }
14405
14406 return ExprEvaluatorBaseTy::VisitCallExpr(E);
14407 }
14408
14409 bool VisitCXXDeleteExpr(const CXXDeleteExpr *E);
14410};
14411} // end anonymous namespace
14412
14413bool VoidExprEvaluator::VisitCXXDeleteExpr(const CXXDeleteExpr *E) {
14414 // We cannot speculatively evaluate a delete expression.
14415 if (Info.SpeculativeEvaluationDepth)
14416 return false;
14417
14418 FunctionDecl *OperatorDelete = E->getOperatorDelete();
14419 if (!OperatorDelete->isReplaceableGlobalAllocationFunction()) {
14420 Info.FFDiag(E, diag::note_constexpr_new_non_replaceable)
14421 << isa<CXXMethodDecl>(OperatorDelete) << OperatorDelete;
14422 return false;
14423 }
14424
14425 const Expr *Arg = E->getArgument();
14426
14427 LValue Pointer;
14428 if (!EvaluatePointer(Arg, Pointer, Info))
14429 return false;
14430 if (Pointer.Designator.Invalid)
14431 return false;
14432
14433 // Deleting a null pointer has no effect.
14434 if (Pointer.isNullPointer()) {
14435 // This is the only case where we need to produce an extension warning:
14436 // the only other way we can succeed is if we find a dynamic allocation,
14437 // and we will have warned when we allocated it in that case.
14438 if (!Info.getLangOpts().CPlusPlus20)
14439 Info.CCEDiag(E, diag::note_constexpr_new);
14440 return true;
14441 }
14442
14443 Optional<DynAlloc *> Alloc = CheckDeleteKind(
14444 Info, E, Pointer, E->isArrayForm() ? DynAlloc::ArrayNew : DynAlloc::New);
14445 if (!Alloc)
14446 return false;
14447 QualType AllocType = Pointer.Base.getDynamicAllocType();
14448
14449 // For the non-array case, the designator must be empty if the static type
14450 // does not have a virtual destructor.
14451 if (!E->isArrayForm() && Pointer.Designator.Entries.size() != 0 &&
14452 !hasVirtualDestructor(Arg->getType()->getPointeeType())) {
14453 Info.FFDiag(E, diag::note_constexpr_delete_base_nonvirt_dtor)
14454 << Arg->getType()->getPointeeType() << AllocType;
14455 return false;
14456 }
14457
14458 // For a class type with a virtual destructor, the selected operator delete
14459 // is the one looked up when building the destructor.
14460 if (!E->isArrayForm() && !E->isGlobalDelete()) {
14461 const FunctionDecl *VirtualDelete = getVirtualOperatorDelete(AllocType);
14462 if (VirtualDelete &&
14463 !VirtualDelete->isReplaceableGlobalAllocationFunction()) {
14464 Info.FFDiag(E, diag::note_constexpr_new_non_replaceable)
14465 << isa<CXXMethodDecl>(VirtualDelete) << VirtualDelete;
14466 return false;
14467 }
14468 }
14469
14470 if (!HandleDestruction(Info, E->getExprLoc(), Pointer.getLValueBase(),
14471 (*Alloc)->Value, AllocType))
14472 return false;
14473
14474 if (!Info.HeapAllocs.erase(Pointer.Base.dyn_cast<DynamicAllocLValue>())) {
14475 // The element was already erased. This means the destructor call also
14476 // deleted the object.
14477 // FIXME: This probably results in undefined behavior before we get this
14478 // far, and should be diagnosed elsewhere first.
14479 Info.FFDiag(E, diag::note_constexpr_double_delete);
14480 return false;
14481 }
14482
14483 return true;
14484}
14485
14486static bool EvaluateVoid(const Expr *E, EvalInfo &Info) {
14487 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14487, __extension__ __PRETTY_FUNCTION__))
;
14488 assert(E->isPRValue() && E->getType()->isVoidType())(static_cast <bool> (E->isPRValue() && E->
getType()->isVoidType()) ? void (0) : __assert_fail ("E->isPRValue() && E->getType()->isVoidType()"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14488, __extension__ __PRETTY_FUNCTION__))
;
14489 return VoidExprEvaluator(Info).Visit(E);
14490}
14491
14492//===----------------------------------------------------------------------===//
14493// Top level Expr::EvaluateAsRValue method.
14494//===----------------------------------------------------------------------===//
14495
14496static bool Evaluate(APValue &Result, EvalInfo &Info, const Expr *E) {
14497 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14497, __extension__ __PRETTY_FUNCTION__))
;
14498 // In C, function designators are not lvalues, but we evaluate them as if they
14499 // are.
14500 QualType T = E->getType();
14501 if (E->isGLValue() || T->isFunctionType()) {
14502 LValue LV;
14503 if (!EvaluateLValue(E, LV, Info))
14504 return false;
14505 LV.moveInto(Result);
14506 } else if (T->isVectorType()) {
14507 if (!EvaluateVector(E, Result, Info))
14508 return false;
14509 } else if (T->isIntegralOrEnumerationType()) {
14510 if (!IntExprEvaluator(Info, Result).Visit(E))
14511 return false;
14512 } else if (T->hasPointerRepresentation()) {
14513 LValue LV;
14514 if (!EvaluatePointer(E, LV, Info))
14515 return false;
14516 LV.moveInto(Result);
14517 } else if (T->isRealFloatingType()) {
14518 llvm::APFloat F(0.0);
14519 if (!EvaluateFloat(E, F, Info))
14520 return false;
14521 Result = APValue(F);
14522 } else if (T->isAnyComplexType()) {
14523 ComplexValue C;
14524 if (!EvaluateComplex(E, C, Info))
14525 return false;
14526 C.moveInto(Result);
14527 } else if (T->isFixedPointType()) {
14528 if (!FixedPointExprEvaluator(Info, Result).Visit(E)) return false;
14529 } else if (T->isMemberPointerType()) {
14530 MemberPtr P;
14531 if (!EvaluateMemberPointer(E, P, Info))
14532 return false;
14533 P.moveInto(Result);
14534 return true;
14535 } else if (T->isArrayType()) {
14536 LValue LV;
14537 APValue &Value =
14538 Info.CurrentCall->createTemporary(E, T, ScopeKind::FullExpression, LV);
14539 if (!EvaluateArray(E, LV, Value, Info))
14540 return false;
14541 Result = Value;
14542 } else if (T->isRecordType()) {
14543 LValue LV;
14544 APValue &Value =
14545 Info.CurrentCall->createTemporary(E, T, ScopeKind::FullExpression, LV);
14546 if (!EvaluateRecord(E, LV, Value, Info))
14547 return false;
14548 Result = Value;
14549 } else if (T->isVoidType()) {
14550 if (!Info.getLangOpts().CPlusPlus11)
14551 Info.CCEDiag(E, diag::note_constexpr_nonliteral)
14552 << E->getType();
14553 if (!EvaluateVoid(E, Info))
14554 return false;
14555 } else if (T->isAtomicType()) {
14556 QualType Unqual = T.getAtomicUnqualifiedType();
14557 if (Unqual->isArrayType() || Unqual->isRecordType()) {
14558 LValue LV;
14559 APValue &Value = Info.CurrentCall->createTemporary(
14560 E, Unqual, ScopeKind::FullExpression, LV);
14561 if (!EvaluateAtomic(E, &LV, Value, Info))
14562 return false;
14563 } else {
14564 if (!EvaluateAtomic(E, nullptr, Result, Info))
14565 return false;
14566 }
14567 } else if (Info.getLangOpts().CPlusPlus11) {
14568 Info.FFDiag(E, diag::note_constexpr_nonliteral) << E->getType();
14569 return false;
14570 } else {
14571 Info.FFDiag(E, diag::note_invalid_subexpr_in_const_expr);
14572 return false;
14573 }
14574
14575 return true;
14576}
14577
14578/// EvaluateInPlace - Evaluate an expression in-place in an APValue. In some
14579/// cases, the in-place evaluation is essential, since later initializers for
14580/// an object can indirectly refer to subobjects which were initialized earlier.
14581static bool EvaluateInPlace(APValue &Result, EvalInfo &Info, const LValue &This,
14582 const Expr *E, bool AllowNonLiteralTypes) {
14583 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14583, __extension__ __PRETTY_FUNCTION__))
;
14584
14585 if (!AllowNonLiteralTypes && !CheckLiteralType(Info, E, &This))
14586 return false;
14587
14588 if (E->isPRValue()) {
14589 // Evaluate arrays and record types in-place, so that later initializers can
14590 // refer to earlier-initialized members of the object.
14591 QualType T = E->getType();
14592 if (T->isArrayType())
14593 return EvaluateArray(E, This, Result, Info);
14594 else if (T->isRecordType())
14595 return EvaluateRecord(E, This, Result, Info);
14596 else if (T->isAtomicType()) {
14597 QualType Unqual = T.getAtomicUnqualifiedType();
14598 if (Unqual->isArrayType() || Unqual->isRecordType())
14599 return EvaluateAtomic(E, &This, Result, Info);
14600 }
14601 }
14602
14603 // For any other type, in-place evaluation is unimportant.
14604 return Evaluate(Result, Info, E);
14605}
14606
14607/// EvaluateAsRValue - Try to evaluate this expression, performing an implicit
14608/// lvalue-to-rvalue cast if it is an lvalue.
14609static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result) {
14610 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14610, __extension__ __PRETTY_FUNCTION__))
;
14611 if (Info.EnableNewConstInterp) {
14612 if (!Info.Ctx.getInterpContext().evaluateAsRValue(Info, E, Result))
14613 return false;
14614 } else {
14615 if (E->getType().isNull())
14616 return false;
14617
14618 if (!CheckLiteralType(Info, E))
14619 return false;
14620
14621 if (!::Evaluate(Result, Info, E))
14622 return false;
14623
14624 if (E->isGLValue()) {
14625 LValue LV;
14626 LV.setFrom(Info.Ctx, Result);
14627 if (!handleLValueToRValueConversion(Info, E, E->getType(), LV, Result))
14628 return false;
14629 }
14630 }
14631
14632 // Check this core constant expression is a constant expression.
14633 return CheckConstantExpression(Info, E->getExprLoc(), E->getType(), Result,
14634 ConstantExprKind::Normal) &&
14635 CheckMemoryLeaks(Info);
14636}
14637
14638static bool FastEvaluateAsRValue(const Expr *Exp, Expr::EvalResult &Result,
14639 const ASTContext &Ctx, bool &IsConst) {
14640 // Fast-path evaluations of integer literals, since we sometimes see files
14641 // containing vast quantities of these.
14642 if (const IntegerLiteral *L = dyn_cast<IntegerLiteral>(Exp)) {
14643 Result.Val = APValue(APSInt(L->getValue(),
14644 L->getType()->isUnsignedIntegerType()));
14645 IsConst = true;
14646 return true;
14647 }
14648
14649 // This case should be rare, but we need to check it before we check on
14650 // the type below.
14651 if (Exp->getType().isNull()) {
14652 IsConst = false;
14653 return true;
14654 }
14655
14656 // FIXME: Evaluating values of large array and record types can cause
14657 // performance problems. Only do so in C++11 for now.
14658 if (Exp->isPRValue() &&
14659 (Exp->getType()->isArrayType() || Exp->getType()->isRecordType()) &&
14660 !Ctx.getLangOpts().CPlusPlus11) {
14661 IsConst = false;
14662 return true;
14663 }
14664 return false;
14665}
14666
14667static bool hasUnacceptableSideEffect(Expr::EvalStatus &Result,
14668 Expr::SideEffectsKind SEK) {
14669 return (SEK < Expr::SE_AllowSideEffects && Result.HasSideEffects) ||
14670 (SEK < Expr::SE_AllowUndefinedBehavior && Result.HasUndefinedBehavior);
14671}
14672
14673static bool EvaluateAsRValue(const Expr *E, Expr::EvalResult &Result,
14674 const ASTContext &Ctx, EvalInfo &Info) {
14675 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14675, __extension__ __PRETTY_FUNCTION__))
;
14676 bool IsConst;
14677 if (FastEvaluateAsRValue(E, Result, Ctx, IsConst))
14678 return IsConst;
14679
14680 return EvaluateAsRValue(Info, E, Result.Val);
14681}
14682
14683static bool EvaluateAsInt(const Expr *E, Expr::EvalResult &ExprResult,
14684 const ASTContext &Ctx,
14685 Expr::SideEffectsKind AllowSideEffects,
14686 EvalInfo &Info) {
14687 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14687, __extension__ __PRETTY_FUNCTION__))
;
14688 if (!E->getType()->isIntegralOrEnumerationType())
14689 return false;
14690
14691 if (!::EvaluateAsRValue(E, ExprResult, Ctx, Info) ||
14692 !ExprResult.Val.isInt() ||
14693 hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
14694 return false;
14695
14696 return true;
14697}
14698
14699static bool EvaluateAsFixedPoint(const Expr *E, Expr::EvalResult &ExprResult,
14700 const ASTContext &Ctx,
14701 Expr::SideEffectsKind AllowSideEffects,
14702 EvalInfo &Info) {
14703 assert(!E->isValueDependent())(static_cast <bool> (!E->isValueDependent()) ? void (
0) : __assert_fail ("!E->isValueDependent()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14703, __extension__ __PRETTY_FUNCTION__))
;
14704 if (!E->getType()->isFixedPointType())
14705 return false;
14706
14707 if (!::EvaluateAsRValue(E, ExprResult, Ctx, Info))
14708 return false;
14709
14710 if (!ExprResult.Val.isFixedPoint() ||
14711 hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
14712 return false;
14713
14714 return true;
14715}
14716
14717/// EvaluateAsRValue - Return true if this is a constant which we can fold using
14718/// any crazy technique (that has nothing to do with language standards) that
14719/// we want to. If this function returns true, it returns the folded constant
14720/// in Result. If this expression is a glvalue, an lvalue-to-rvalue conversion
14721/// will be applied to the result.
14722bool Expr::EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx,
14723 bool InConstantContext) const {
14724 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14725, __extension__ __PRETTY_FUNCTION__))
14725 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14725, __extension__ __PRETTY_FUNCTION__))
;
14726 EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects);
14727 Info.InConstantContext = InConstantContext;
14728 return ::EvaluateAsRValue(this, Result, Ctx, Info);
14729}
14730
14731bool Expr::EvaluateAsBooleanCondition(bool &Result, const ASTContext &Ctx,
14732 bool InConstantContext) const {
14733 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14734, __extension__ __PRETTY_FUNCTION__))
14734 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14734, __extension__ __PRETTY_FUNCTION__))
;
14735 EvalResult Scratch;
14736 return EvaluateAsRValue(Scratch, Ctx, InConstantContext) &&
14737 HandleConversionToBool(Scratch.Val, Result);
14738}
14739
14740bool Expr::EvaluateAsInt(EvalResult &Result, const ASTContext &Ctx,
14741 SideEffectsKind AllowSideEffects,
14742 bool InConstantContext) const {
14743 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14744, __extension__ __PRETTY_FUNCTION__))
14744 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14744, __extension__ __PRETTY_FUNCTION__))
;
14745 EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects);
14746 Info.InConstantContext = InConstantContext;
14747 return ::EvaluateAsInt(this, Result, Ctx, AllowSideEffects, Info);
14748}
14749
14750bool Expr::EvaluateAsFixedPoint(EvalResult &Result, const ASTContext &Ctx,
14751 SideEffectsKind AllowSideEffects,
14752 bool InConstantContext) const {
14753 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14754, __extension__ __PRETTY_FUNCTION__))
14754 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14754, __extension__ __PRETTY_FUNCTION__))
;
14755 EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects);
14756 Info.InConstantContext = InConstantContext;
14757 return ::EvaluateAsFixedPoint(this, Result, Ctx, AllowSideEffects, Info);
14758}
14759
14760bool Expr::EvaluateAsFloat(APFloat &Result, const ASTContext &Ctx,
14761 SideEffectsKind AllowSideEffects,
14762 bool InConstantContext) const {
14763 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14764, __extension__ __PRETTY_FUNCTION__))
14764 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14764, __extension__ __PRETTY_FUNCTION__))
;
14765
14766 if (!getType()->isRealFloatingType())
14767 return false;
14768
14769 EvalResult ExprResult;
14770 if (!EvaluateAsRValue(ExprResult, Ctx, InConstantContext) ||
14771 !ExprResult.Val.isFloat() ||
14772 hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
14773 return false;
14774
14775 Result = ExprResult.Val.getFloat();
14776 return true;
14777}
14778
14779bool Expr::EvaluateAsLValue(EvalResult &Result, const ASTContext &Ctx,
14780 bool InConstantContext) const {
14781 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14782, __extension__ __PRETTY_FUNCTION__))
14782 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14782, __extension__ __PRETTY_FUNCTION__))
;
14783
14784 EvalInfo Info(Ctx, Result, EvalInfo::EM_ConstantFold);
14785 Info.InConstantContext = InConstantContext;
14786 LValue LV;
14787 CheckedTemporaries CheckedTemps;
14788 if (!EvaluateLValue(this, LV, Info) || !Info.discardCleanups() ||
14789 Result.HasSideEffects ||
14790 !CheckLValueConstantExpression(Info, getExprLoc(),
14791 Ctx.getLValueReferenceType(getType()), LV,
14792 ConstantExprKind::Normal, CheckedTemps))
14793 return false;
14794
14795 LV.moveInto(Result.Val);
14796 return true;
14797}
14798
14799static bool EvaluateDestruction(const ASTContext &Ctx, APValue::LValueBase Base,
14800 APValue DestroyedValue, QualType Type,
14801 SourceLocation Loc, Expr::EvalStatus &EStatus,
14802 bool IsConstantDestruction) {
14803 EvalInfo Info(Ctx, EStatus,
14804 IsConstantDestruction ? EvalInfo::EM_ConstantExpression
14805 : EvalInfo::EM_ConstantFold);
14806 Info.setEvaluatingDecl(Base, DestroyedValue,
14807 EvalInfo::EvaluatingDeclKind::Dtor);
14808 Info.InConstantContext = IsConstantDestruction;
14809
14810 LValue LVal;
14811 LVal.set(Base);
14812
14813 if (!HandleDestruction(Info, Loc, Base, DestroyedValue, Type) ||
14814 EStatus.HasSideEffects)
14815 return false;
14816
14817 if (!Info.discardCleanups())
14818 llvm_unreachable("Unhandled cleanup; missing full expression marker?")::llvm::llvm_unreachable_internal("Unhandled cleanup; missing full expression marker?"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14818)
;
14819
14820 return true;
14821}
14822
14823bool Expr::EvaluateAsConstantExpr(EvalResult &Result, const ASTContext &Ctx,
14824 ConstantExprKind Kind) const {
14825 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14826, __extension__ __PRETTY_FUNCTION__))
14826 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14826, __extension__ __PRETTY_FUNCTION__))
;
14827
14828 EvalInfo::EvaluationMode EM = EvalInfo::EM_ConstantExpression;
14829 EvalInfo Info(Ctx, Result, EM);
14830 Info.InConstantContext = true;
14831
14832 // The type of the object we're initializing is 'const T' for a class NTTP.
14833 QualType T = getType();
14834 if (Kind == ConstantExprKind::ClassTemplateArgument)
14835 T.addConst();
14836
14837 // If we're evaluating a prvalue, fake up a MaterializeTemporaryExpr to
14838 // represent the result of the evaluation. CheckConstantExpression ensures
14839 // this doesn't escape.
14840 MaterializeTemporaryExpr BaseMTE(T, const_cast<Expr*>(this), true);
14841 APValue::LValueBase Base(&BaseMTE);
14842
14843 Info.setEvaluatingDecl(Base, Result.Val);
14844 LValue LVal;
14845 LVal.set(Base);
14846
14847 if (!::EvaluateInPlace(Result.Val, Info, LVal, this) || Result.HasSideEffects)
14848 return false;
14849
14850 if (!Info.discardCleanups())
14851 llvm_unreachable("Unhandled cleanup; missing full expression marker?")::llvm::llvm_unreachable_internal("Unhandled cleanup; missing full expression marker?"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14851)
;
14852
14853 if (!CheckConstantExpression(Info, getExprLoc(), getStorageType(Ctx, this),
14854 Result.Val, Kind))
14855 return false;
14856 if (!CheckMemoryLeaks(Info))
14857 return false;
14858
14859 // If this is a class template argument, it's required to have constant
14860 // destruction too.
14861 if (Kind == ConstantExprKind::ClassTemplateArgument &&
14862 (!EvaluateDestruction(Ctx, Base, Result.Val, T, getBeginLoc(), Result,
14863 true) ||
14864 Result.HasSideEffects)) {
14865 // FIXME: Prefix a note to indicate that the problem is lack of constant
14866 // destruction.
14867 return false;
14868 }
14869
14870 return true;
14871}
14872
14873bool Expr::EvaluateAsInitializer(APValue &Value, const ASTContext &Ctx,
14874 const VarDecl *VD,
14875 SmallVectorImpl<PartialDiagnosticAt> &Notes,
14876 bool IsConstantInitialization) const {
14877 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14878, __extension__ __PRETTY_FUNCTION__))
14878 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14878, __extension__ __PRETTY_FUNCTION__))
;
14879
14880 // FIXME: Evaluating initializers for large array and record types can cause
14881 // performance problems. Only do so in C++11 for now.
14882 if (isPRValue() && (getType()->isArrayType() || getType()->isRecordType()) &&
14883 !Ctx.getLangOpts().CPlusPlus11)
14884 return false;
14885
14886 Expr::EvalStatus EStatus;
14887 EStatus.Diag = &Notes;
14888
14889 EvalInfo Info(Ctx, EStatus,
14890 (IsConstantInitialization && Ctx.getLangOpts().CPlusPlus11)
14891 ? EvalInfo::EM_ConstantExpression
14892 : EvalInfo::EM_ConstantFold);
14893 Info.setEvaluatingDecl(VD, Value);
14894 Info.InConstantContext = IsConstantInitialization;
14895
14896 SourceLocation DeclLoc = VD->getLocation();
14897 QualType DeclTy = VD->getType();
14898
14899 if (Info.EnableNewConstInterp) {
14900 auto &InterpCtx = const_cast<ASTContext &>(Ctx).getInterpContext();
14901 if (!InterpCtx.evaluateAsInitializer(Info, VD, Value))
14902 return false;
14903 } else {
14904 LValue LVal;
14905 LVal.set(VD);
14906
14907 if (!EvaluateInPlace(Value, Info, LVal, this,
14908 /*AllowNonLiteralTypes=*/true) ||
14909 EStatus.HasSideEffects)
14910 return false;
14911
14912 // At this point, any lifetime-extended temporaries are completely
14913 // initialized.
14914 Info.performLifetimeExtension();
14915
14916 if (!Info.discardCleanups())
14917 llvm_unreachable("Unhandled cleanup; missing full expression marker?")::llvm::llvm_unreachable_internal("Unhandled cleanup; missing full expression marker?"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14917)
;
14918 }
14919 return CheckConstantExpression(Info, DeclLoc, DeclTy, Value,
14920 ConstantExprKind::Normal) &&
14921 CheckMemoryLeaks(Info);
14922}
14923
14924bool VarDecl::evaluateDestruction(
14925 SmallVectorImpl<PartialDiagnosticAt> &Notes) const {
14926 Expr::EvalStatus EStatus;
14927 EStatus.Diag = &Notes;
14928
14929 // Only treat the destruction as constant destruction if we formally have
14930 // constant initialization (or are usable in a constant expression).
14931 bool IsConstantDestruction = hasConstantInitialization();
14932
14933 // Make a copy of the value for the destructor to mutate, if we know it.
14934 // Otherwise, treat the value as default-initialized; if the destructor works
14935 // anyway, then the destruction is constant (and must be essentially empty).
14936 APValue DestroyedValue;
14937 if (getEvaluatedValue() && !getEvaluatedValue()->isAbsent())
14938 DestroyedValue = *getEvaluatedValue();
14939 else if (!getDefaultInitValue(getType(), DestroyedValue))
14940 return false;
14941
14942 if (!EvaluateDestruction(getASTContext(), this, std::move(DestroyedValue),
14943 getType(), getLocation(), EStatus,
14944 IsConstantDestruction) ||
14945 EStatus.HasSideEffects)
14946 return false;
14947
14948 ensureEvaluatedStmt()->HasConstantDestruction = true;
14949 return true;
14950}
14951
14952/// isEvaluatable - Call EvaluateAsRValue to see if this expression can be
14953/// constant folded, but discard the result.
14954bool Expr::isEvaluatable(const ASTContext &Ctx, SideEffectsKind SEK) const {
14955 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14956, __extension__ __PRETTY_FUNCTION__))
14956 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14956, __extension__ __PRETTY_FUNCTION__))
;
14957
14958 EvalResult Result;
14959 return EvaluateAsRValue(Result, Ctx, /* in constant context */ true) &&
14960 !hasUnacceptableSideEffect(Result, SEK);
14961}
14962
14963APSInt Expr::EvaluateKnownConstInt(const ASTContext &Ctx,
14964 SmallVectorImpl<PartialDiagnosticAt> *Diag) const {
14965 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14966, __extension__ __PRETTY_FUNCTION__))
14966 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14966, __extension__ __PRETTY_FUNCTION__))
;
14967
14968 EvalResult EVResult;
14969 EVResult.Diag = Diag;
14970 EvalInfo Info(Ctx, EVResult, EvalInfo::EM_IgnoreSideEffects);
14971 Info.InConstantContext = true;
14972
14973 bool Result = ::EvaluateAsRValue(this, EVResult, Ctx, Info);
14974 (void)Result;
14975 assert(Result && "Could not evaluate expression")(static_cast <bool> (Result && "Could not evaluate expression"
) ? void (0) : __assert_fail ("Result && \"Could not evaluate expression\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14975, __extension__ __PRETTY_FUNCTION__))
;
14976 assert(EVResult.Val.isInt() && "Expression did not evaluate to integer")(static_cast <bool> (EVResult.Val.isInt() && "Expression did not evaluate to integer"
) ? void (0) : __assert_fail ("EVResult.Val.isInt() && \"Expression did not evaluate to integer\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14976, __extension__ __PRETTY_FUNCTION__))
;
14977
14978 return EVResult.Val.getInt();
14979}
14980
14981APSInt Expr::EvaluateKnownConstIntCheckOverflow(
14982 const ASTContext &Ctx, SmallVectorImpl<PartialDiagnosticAt> *Diag) const {
14983 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14984, __extension__ __PRETTY_FUNCTION__))
14984 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14984, __extension__ __PRETTY_FUNCTION__))
;
14985
14986 EvalResult EVResult;
14987 EVResult.Diag = Diag;
14988 EvalInfo Info(Ctx, EVResult, EvalInfo::EM_IgnoreSideEffects);
14989 Info.InConstantContext = true;
14990 Info.CheckingForUndefinedBehavior = true;
14991
14992 bool Result = ::EvaluateAsRValue(Info, this, EVResult.Val);
14993 (void)Result;
14994 assert(Result && "Could not evaluate expression")(static_cast <bool> (Result && "Could not evaluate expression"
) ? void (0) : __assert_fail ("Result && \"Could not evaluate expression\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14994, __extension__ __PRETTY_FUNCTION__))
;
14995 assert(EVResult.Val.isInt() && "Expression did not evaluate to integer")(static_cast <bool> (EVResult.Val.isInt() && "Expression did not evaluate to integer"
) ? void (0) : __assert_fail ("EVResult.Val.isInt() && \"Expression did not evaluate to integer\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 14995, __extension__ __PRETTY_FUNCTION__))
;
14996
14997 return EVResult.Val.getInt();
14998}
14999
15000void Expr::EvaluateForOverflow(const ASTContext &Ctx) const {
15001 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15002, __extension__ __PRETTY_FUNCTION__))
15002 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15002, __extension__ __PRETTY_FUNCTION__))
;
15003
15004 bool IsConst;
15005 EvalResult EVResult;
15006 if (!FastEvaluateAsRValue(this, EVResult, Ctx, IsConst)) {
15007 EvalInfo Info(Ctx, EVResult, EvalInfo::EM_IgnoreSideEffects);
15008 Info.CheckingForUndefinedBehavior = true;
15009 (void)::EvaluateAsRValue(Info, this, EVResult.Val);
15010 }
15011}
15012
15013bool Expr::EvalResult::isGlobalLValue() const {
15014 assert(Val.isLValue())(static_cast <bool> (Val.isLValue()) ? void (0) : __assert_fail
("Val.isLValue()", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15014, __extension__ __PRETTY_FUNCTION__))
;
15015 return IsGlobalLValue(Val.getLValueBase());
15016}
15017
15018/// isIntegerConstantExpr - this recursive routine will test if an expression is
15019/// an integer constant expression.
15020
15021/// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero,
15022/// comma, etc
15023
15024// CheckICE - This function does the fundamental ICE checking: the returned
15025// ICEDiag contains an ICEKind indicating whether the expression is an ICE,
15026// and a (possibly null) SourceLocation indicating the location of the problem.
15027//
15028// Note that to reduce code duplication, this helper does no evaluation
15029// itself; the caller checks whether the expression is evaluatable, and
15030// in the rare cases where CheckICE actually cares about the evaluated
15031// value, it calls into Evaluate.
15032
15033namespace {
15034
15035enum ICEKind {
15036 /// This expression is an ICE.
15037 IK_ICE,
15038 /// This expression is not an ICE, but if it isn't evaluated, it's
15039 /// a legal subexpression for an ICE. This return value is used to handle
15040 /// the comma operator in C99 mode, and non-constant subexpressions.
15041 IK_ICEIfUnevaluated,
15042 /// This expression is not an ICE, and is not a legal subexpression for one.
15043 IK_NotICE
15044};
15045
15046struct ICEDiag {
15047 ICEKind Kind;
15048 SourceLocation Loc;
15049
15050 ICEDiag(ICEKind IK, SourceLocation l) : Kind(IK), Loc(l) {}
15051};
15052
15053}
15054
15055static ICEDiag NoDiag() { return ICEDiag(IK_ICE, SourceLocation()); }
15056
15057static ICEDiag Worst(ICEDiag A, ICEDiag B) { return A.Kind >= B.Kind ? A : B; }
15058
15059static ICEDiag CheckEvalInICE(const Expr* E, const ASTContext &Ctx) {
15060 Expr::EvalResult EVResult;
15061 Expr::EvalStatus Status;
15062 EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpression);
15063
15064 Info.InConstantContext = true;
15065 if (!::EvaluateAsRValue(E, EVResult, Ctx, Info) || EVResult.HasSideEffects ||
15066 !EVResult.Val.isInt())
15067 return ICEDiag(IK_NotICE, E->getBeginLoc());
15068
15069 return NoDiag();
15070}
15071
15072static ICEDiag CheckICE(const Expr* E, const ASTContext &Ctx) {
15073 assert(!E->isValueDependent() && "Should not see value dependent exprs!")(static_cast <bool> (!E->isValueDependent() &&
"Should not see value dependent exprs!") ? void (0) : __assert_fail
("!E->isValueDependent() && \"Should not see value dependent exprs!\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15073, __extension__ __PRETTY_FUNCTION__))
;
15074 if (!E->getType()->isIntegralOrEnumerationType())
15075 return ICEDiag(IK_NotICE, E->getBeginLoc());
15076
15077 switch (E->getStmtClass()) {
15078#define ABSTRACT_STMT(Node)
15079#define STMT(Node, Base) case Expr::Node##Class:
15080#define EXPR(Node, Base)
15081#include "clang/AST/StmtNodes.inc"
15082 case Expr::PredefinedExprClass:
15083 case Expr::FloatingLiteralClass:
15084 case Expr::ImaginaryLiteralClass:
15085 case Expr::StringLiteralClass:
15086 case Expr::ArraySubscriptExprClass:
15087 case Expr::MatrixSubscriptExprClass:
15088 case Expr::OMPArraySectionExprClass:
15089 case Expr::OMPArrayShapingExprClass:
15090 case Expr::OMPIteratorExprClass:
15091 case Expr::MemberExprClass:
15092 case Expr::CompoundAssignOperatorClass:
15093 case Expr::CompoundLiteralExprClass:
15094 case Expr::ExtVectorElementExprClass:
15095 case Expr::DesignatedInitExprClass:
15096 case Expr::ArrayInitLoopExprClass:
15097 case Expr::ArrayInitIndexExprClass:
15098 case Expr::NoInitExprClass:
15099 case Expr::DesignatedInitUpdateExprClass:
15100 case Expr::ImplicitValueInitExprClass:
15101 case Expr::ParenListExprClass:
15102 case Expr::VAArgExprClass:
15103 case Expr::AddrLabelExprClass:
15104 case Expr::StmtExprClass:
15105 case Expr::CXXMemberCallExprClass:
15106 case Expr::CUDAKernelCallExprClass:
15107 case Expr::CXXAddrspaceCastExprClass:
15108 case Expr::CXXDynamicCastExprClass:
15109 case Expr::CXXTypeidExprClass:
15110 case Expr::CXXUuidofExprClass:
15111 case Expr::MSPropertyRefExprClass:
15112 case Expr::MSPropertySubscriptExprClass:
15113 case Expr::CXXNullPtrLiteralExprClass:
15114 case Expr::UserDefinedLiteralClass:
15115 case Expr::CXXThisExprClass:
15116 case Expr::CXXThrowExprClass:
15117 case Expr::CXXNewExprClass:
15118 case Expr::CXXDeleteExprClass:
15119 case Expr::CXXPseudoDestructorExprClass:
15120 case Expr::UnresolvedLookupExprClass:
15121 case Expr::TypoExprClass:
15122 case Expr::RecoveryExprClass:
15123 case Expr::DependentScopeDeclRefExprClass:
15124 case Expr::CXXConstructExprClass:
15125 case Expr::CXXInheritedCtorInitExprClass:
15126 case Expr::CXXStdInitializerListExprClass:
15127 case Expr::CXXBindTemporaryExprClass:
15128 case Expr::ExprWithCleanupsClass:
15129 case Expr::CXXTemporaryObjectExprClass:
15130 case Expr::CXXUnresolvedConstructExprClass:
15131 case Expr::CXXDependentScopeMemberExprClass:
15132 case Expr::UnresolvedMemberExprClass:
15133 case Expr::ObjCStringLiteralClass:
15134 case Expr::ObjCBoxedExprClass:
15135 case Expr::ObjCArrayLiteralClass:
15136 case Expr::ObjCDictionaryLiteralClass:
15137 case Expr::ObjCEncodeExprClass:
15138 case Expr::ObjCMessageExprClass:
15139 case Expr::ObjCSelectorExprClass:
15140 case Expr::ObjCProtocolExprClass:
15141 case Expr::ObjCIvarRefExprClass:
15142 case Expr::ObjCPropertyRefExprClass:
15143 case Expr::ObjCSubscriptRefExprClass:
15144 case Expr::ObjCIsaExprClass:
15145 case Expr::ObjCAvailabilityCheckExprClass:
15146 case Expr::ShuffleVectorExprClass:
15147 case Expr::ConvertVectorExprClass:
15148 case Expr::BlockExprClass:
15149 case Expr::NoStmtClass:
15150 case Expr::OpaqueValueExprClass:
15151 case Expr::PackExpansionExprClass:
15152 case Expr::SubstNonTypeTemplateParmPackExprClass:
15153 case Expr::FunctionParmPackExprClass:
15154 case Expr::AsTypeExprClass:
15155 case Expr::ObjCIndirectCopyRestoreExprClass:
15156 case Expr::MaterializeTemporaryExprClass:
15157 case Expr::PseudoObjectExprClass:
15158 case Expr::AtomicExprClass:
15159 case Expr::LambdaExprClass:
15160 case Expr::CXXFoldExprClass:
15161 case Expr::CoawaitExprClass:
15162 case Expr::DependentCoawaitExprClass:
15163 case Expr::CoyieldExprClass:
15164 case Expr::SYCLUniqueStableNameExprClass:
15165 return ICEDiag(IK_NotICE, E->getBeginLoc());
15166
15167 case Expr::InitListExprClass: {
15168 // C++03 [dcl.init]p13: If T is a scalar type, then a declaration of the
15169 // form "T x = { a };" is equivalent to "T x = a;".
15170 // Unless we're initializing a reference, T is a scalar as it is known to be
15171 // of integral or enumeration type.
15172 if (E->isPRValue())
15173 if (cast<InitListExpr>(E)->getNumInits() == 1)
15174 return CheckICE(cast<InitListExpr>(E)->getInit(0), Ctx);
15175 return ICEDiag(IK_NotICE, E->getBeginLoc());
15176 }
15177
15178 case Expr::SizeOfPackExprClass:
15179 case Expr::GNUNullExprClass:
15180 case Expr::SourceLocExprClass:
15181 return NoDiag();
15182
15183 case Expr::SubstNonTypeTemplateParmExprClass:
15184 return
15185 CheckICE(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement(), Ctx);
15186
15187 case Expr::ConstantExprClass:
15188 return CheckICE(cast<ConstantExpr>(E)->getSubExpr(), Ctx);
15189
15190 case Expr::ParenExprClass:
15191 return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx);
15192 case Expr::GenericSelectionExprClass:
15193 return CheckICE(cast<GenericSelectionExpr>(E)->getResultExpr(), Ctx);
15194 case Expr::IntegerLiteralClass:
15195 case Expr::FixedPointLiteralClass:
15196 case Expr::CharacterLiteralClass:
15197 case Expr::ObjCBoolLiteralExprClass:
15198 case Expr::CXXBoolLiteralExprClass:
15199 case Expr::CXXScalarValueInitExprClass:
15200 case Expr::TypeTraitExprClass:
15201 case Expr::ConceptSpecializationExprClass:
15202 case Expr::RequiresExprClass:
15203 case Expr::ArrayTypeTraitExprClass:
15204 case Expr::ExpressionTraitExprClass:
15205 case Expr::CXXNoexceptExprClass:
15206 return NoDiag();
15207 case Expr::CallExprClass:
15208 case Expr::CXXOperatorCallExprClass: {
15209 // C99 6.6/3 allows function calls within unevaluated subexpressions of
15210 // constant expressions, but they can never be ICEs because an ICE cannot
15211 // contain an operand of (pointer to) function type.
15212 const CallExpr *CE = cast<CallExpr>(E);
15213 if (CE->getBuiltinCallee())
15214 return CheckEvalInICE(E, Ctx);
15215 return ICEDiag(IK_NotICE, E->getBeginLoc());
15216 }
15217 case Expr::CXXRewrittenBinaryOperatorClass:
15218 return CheckICE(cast<CXXRewrittenBinaryOperator>(E)->getSemanticForm(),
15219 Ctx);
15220 case Expr::DeclRefExprClass: {
15221 const NamedDecl *D = cast<DeclRefExpr>(E)->getDecl();
15222 if (isa<EnumConstantDecl>(D))
15223 return NoDiag();
15224
15225 // C++ and OpenCL (FIXME: spec reference?) allow reading const-qualified
15226 // integer variables in constant expressions:
15227 //
15228 // C++ 7.1.5.1p2
15229 // A variable of non-volatile const-qualified integral or enumeration
15230 // type initialized by an ICE can be used in ICEs.
15231 //
15232 // We sometimes use CheckICE to check the C++98 rules in C++11 mode. In
15233 // that mode, use of reference variables should not be allowed.
15234 const VarDecl *VD = dyn_cast<VarDecl>(D);
15235 if (VD && VD->isUsableInConstantExpressions(Ctx) &&
15236 !VD->getType()->isReferenceType())
15237 return NoDiag();
15238
15239 return ICEDiag(IK_NotICE, E->getBeginLoc());
15240 }
15241 case Expr::UnaryOperatorClass: {
15242 const UnaryOperator *Exp = cast<UnaryOperator>(E);
15243 switch (Exp->getOpcode()) {
15244 case UO_PostInc:
15245 case UO_PostDec:
15246 case UO_PreInc:
15247 case UO_PreDec:
15248 case UO_AddrOf:
15249 case UO_Deref:
15250 case UO_Coawait:
15251 // C99 6.6/3 allows increment and decrement within unevaluated
15252 // subexpressions of constant expressions, but they can never be ICEs
15253 // because an ICE cannot contain an lvalue operand.
15254 return ICEDiag(IK_NotICE, E->getBeginLoc());
15255 case UO_Extension:
15256 case UO_LNot:
15257 case UO_Plus:
15258 case UO_Minus:
15259 case UO_Not:
15260 case UO_Real:
15261 case UO_Imag:
15262 return CheckICE(Exp->getSubExpr(), Ctx);
15263 }
15264 llvm_unreachable("invalid unary operator class")::llvm::llvm_unreachable_internal("invalid unary operator class"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15264)
;
15265 }
15266 case Expr::OffsetOfExprClass: {
15267 // Note that per C99, offsetof must be an ICE. And AFAIK, using
15268 // EvaluateAsRValue matches the proposed gcc behavior for cases like
15269 // "offsetof(struct s{int x[4];}, x[1.0])". This doesn't affect
15270 // compliance: we should warn earlier for offsetof expressions with
15271 // array subscripts that aren't ICEs, and if the array subscripts
15272 // are ICEs, the value of the offsetof must be an integer constant.
15273 return CheckEvalInICE(E, Ctx);
15274 }
15275 case Expr::UnaryExprOrTypeTraitExprClass: {
15276 const UnaryExprOrTypeTraitExpr *Exp = cast<UnaryExprOrTypeTraitExpr>(E);
15277 if ((Exp->getKind() == UETT_SizeOf) &&
15278 Exp->getTypeOfArgument()->isVariableArrayType())
15279 return ICEDiag(IK_NotICE, E->getBeginLoc());
15280 return NoDiag();
15281 }
15282 case Expr::BinaryOperatorClass: {
15283 const BinaryOperator *Exp = cast<BinaryOperator>(E);
15284 switch (Exp->getOpcode()) {
15285 case BO_PtrMemD:
15286 case BO_PtrMemI:
15287 case BO_Assign:
15288 case BO_MulAssign:
15289 case BO_DivAssign:
15290 case BO_RemAssign:
15291 case BO_AddAssign:
15292 case BO_SubAssign:
15293 case BO_ShlAssign:
15294 case BO_ShrAssign:
15295 case BO_AndAssign:
15296 case BO_XorAssign:
15297 case BO_OrAssign:
15298 // C99 6.6/3 allows assignments within unevaluated subexpressions of
15299 // constant expressions, but they can never be ICEs because an ICE cannot
15300 // contain an lvalue operand.
15301 return ICEDiag(IK_NotICE, E->getBeginLoc());
15302
15303 case BO_Mul:
15304 case BO_Div:
15305 case BO_Rem:
15306 case BO_Add:
15307 case BO_Sub:
15308 case BO_Shl:
15309 case BO_Shr:
15310 case BO_LT:
15311 case BO_GT:
15312 case BO_LE:
15313 case BO_GE:
15314 case BO_EQ:
15315 case BO_NE:
15316 case BO_And:
15317 case BO_Xor:
15318 case BO_Or:
15319 case BO_Comma:
15320 case BO_Cmp: {
15321 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx);
15322 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx);
15323 if (Exp->getOpcode() == BO_Div ||
15324 Exp->getOpcode() == BO_Rem) {
15325 // EvaluateAsRValue gives an error for undefined Div/Rem, so make sure
15326 // we don't evaluate one.
15327 if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICE) {
15328 llvm::APSInt REval = Exp->getRHS()->EvaluateKnownConstInt(Ctx);
15329 if (REval == 0)
15330 return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc());
15331 if (REval.isSigned() && REval.isAllOnes()) {
15332 llvm::APSInt LEval = Exp->getLHS()->EvaluateKnownConstInt(Ctx);
15333 if (LEval.isMinSignedValue())
15334 return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc());
15335 }
15336 }
15337 }
15338 if (Exp->getOpcode() == BO_Comma) {
15339 if (Ctx.getLangOpts().C99) {
15340 // C99 6.6p3 introduces a strange edge case: comma can be in an ICE
15341 // if it isn't evaluated.
15342 if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICE)
15343 return ICEDiag(IK_ICEIfUnevaluated, E->getBeginLoc());
15344 } else {
15345 // In both C89 and C++, commas in ICEs are illegal.
15346 return ICEDiag(IK_NotICE, E->getBeginLoc());
15347 }
15348 }
15349 return Worst(LHSResult, RHSResult);
15350 }
15351 case BO_LAnd:
15352 case BO_LOr: {
15353 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx);
15354 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx);
15355 if (LHSResult.Kind == IK_ICE && RHSResult.Kind == IK_ICEIfUnevaluated) {
15356 // Rare case where the RHS has a comma "side-effect"; we need
15357 // to actually check the condition to see whether the side
15358 // with the comma is evaluated.
15359 if ((Exp->getOpcode() == BO_LAnd) !=
15360 (Exp->getLHS()->EvaluateKnownConstInt(Ctx) == 0))
15361 return RHSResult;
15362 return NoDiag();
15363 }
15364
15365 return Worst(LHSResult, RHSResult);
15366 }
15367 }
15368 llvm_unreachable("invalid binary operator kind")::llvm::llvm_unreachable_internal("invalid binary operator kind"
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15368)
;
15369 }
15370 case Expr::ImplicitCastExprClass:
15371 case Expr::CStyleCastExprClass:
15372 case Expr::CXXFunctionalCastExprClass:
15373 case Expr::CXXStaticCastExprClass:
15374 case Expr::CXXReinterpretCastExprClass:
15375 case Expr::CXXConstCastExprClass:
15376 case Expr::ObjCBridgedCastExprClass: {
15377 const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr();
15378 if (isa<ExplicitCastExpr>(E)) {
15379 if (const FloatingLiteral *FL
15380 = dyn_cast<FloatingLiteral>(SubExpr->IgnoreParenImpCasts())) {
15381 unsigned DestWidth = Ctx.getIntWidth(E->getType());
15382 bool DestSigned = E->getType()->isSignedIntegerOrEnumerationType();
15383 APSInt IgnoredVal(DestWidth, !DestSigned);
15384 bool Ignored;
15385 // If the value does not fit in the destination type, the behavior is
15386 // undefined, so we are not required to treat it as a constant
15387 // expression.
15388 if (FL->getValue().convertToInteger(IgnoredVal,
15389 llvm::APFloat::rmTowardZero,
15390 &Ignored) & APFloat::opInvalidOp)
15391 return ICEDiag(IK_NotICE, E->getBeginLoc());
15392 return NoDiag();
15393 }
15394 }
15395 switch (cast<CastExpr>(E)->getCastKind()) {
15396 case CK_LValueToRValue:
15397 case CK_AtomicToNonAtomic:
15398 case CK_NonAtomicToAtomic:
15399 case CK_NoOp:
15400 case CK_IntegralToBoolean:
15401 case CK_IntegralCast:
15402 return CheckICE(SubExpr, Ctx);
15403 default:
15404 return ICEDiag(IK_NotICE, E->getBeginLoc());
15405 }
15406 }
15407 case Expr::BinaryConditionalOperatorClass: {
15408 const BinaryConditionalOperator *Exp = cast<BinaryConditionalOperator>(E);
15409 ICEDiag CommonResult = CheckICE(Exp->getCommon(), Ctx);
15410 if (CommonResult.Kind == IK_NotICE) return CommonResult;
15411 ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx);
15412 if (FalseResult.Kind == IK_NotICE) return FalseResult;
15413 if (CommonResult.Kind == IK_ICEIfUnevaluated) return CommonResult;
15414 if (FalseResult.Kind == IK_ICEIfUnevaluated &&
15415 Exp->getCommon()->EvaluateKnownConstInt(Ctx) != 0) return NoDiag();
15416 return FalseResult;
15417 }
15418 case Expr::ConditionalOperatorClass: {
15419 const ConditionalOperator *Exp = cast<ConditionalOperator>(E);
15420 // If the condition (ignoring parens) is a __builtin_constant_p call,
15421 // then only the true side is actually considered in an integer constant
15422 // expression, and it is fully evaluated. This is an important GNU
15423 // extension. See GCC PR38377 for discussion.
15424 if (const CallExpr *CallCE
15425 = dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts()))
15426 if (CallCE->getBuiltinCallee() == Builtin::BI__builtin_constant_p)
15427 return CheckEvalInICE(E, Ctx);
15428 ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx);
15429 if (CondResult.Kind == IK_NotICE)
15430 return CondResult;
15431
15432 ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx);
15433 ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx);
15434
15435 if (TrueResult.Kind == IK_NotICE)
15436 return TrueResult;
15437 if (FalseResult.Kind == IK_NotICE)
15438 return FalseResult;
15439 if (CondResult.Kind == IK_ICEIfUnevaluated)
15440 return CondResult;
15441 if (TrueResult.Kind == IK_ICE && FalseResult.Kind == IK_ICE)
15442 return NoDiag();
15443 // Rare case where the diagnostics depend on which side is evaluated
15444 // Note that if we get here, CondResult is 0, and at least one of
15445 // TrueResult and FalseResult is non-zero.
15446 if (Exp->getCond()->EvaluateKnownConstInt(Ctx) == 0)
15447 return FalseResult;
15448 return TrueResult;
15449 }
15450 case Expr::CXXDefaultArgExprClass:
15451 return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx);
15452 case Expr::CXXDefaultInitExprClass:
15453 return CheckICE(cast<CXXDefaultInitExpr>(E)->getExpr(), Ctx);
15454 case Expr::ChooseExprClass: {
15455 return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(), Ctx);
15456 }
15457 case Expr::BuiltinBitCastExprClass: {
15458 if (!checkBitCastConstexprEligibility(nullptr, Ctx, cast<CastExpr>(E)))
15459 return ICEDiag(IK_NotICE, E->getBeginLoc());
15460 return CheckICE(cast<CastExpr>(E)->getSubExpr(), Ctx);
15461 }
15462 }
15463
15464 llvm_unreachable("Invalid StmtClass!")::llvm::llvm_unreachable_internal("Invalid StmtClass!", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15464)
;
15465}
15466
15467/// Evaluate an expression as a C++11 integral constant expression.
15468static bool EvaluateCPlusPlus11IntegralConstantExpr(const ASTContext &Ctx,
15469 const Expr *E,
15470 llvm::APSInt *Value,
15471 SourceLocation *Loc) {
15472 if (!E->getType()->isIntegralOrUnscopedEnumerationType()) {
15473 if (Loc) *Loc = E->getExprLoc();
15474 return false;
15475 }
15476
15477 APValue Result;
15478 if (!E->isCXX11ConstantExpr(Ctx, &Result, Loc))
15479 return false;
15480
15481 if (!Result.isInt()) {
15482 if (Loc) *Loc = E->getExprLoc();
15483 return false;
15484 }
15485
15486 if (Value) *Value = Result.getInt();
15487 return true;
15488}
15489
15490bool Expr::isIntegerConstantExpr(const ASTContext &Ctx,
15491 SourceLocation *Loc) const {
15492 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15493, __extension__ __PRETTY_FUNCTION__))
15493 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15493, __extension__ __PRETTY_FUNCTION__))
;
15494
15495 if (Ctx.getLangOpts().CPlusPlus11)
15496 return EvaluateCPlusPlus11IntegralConstantExpr(Ctx, this, nullptr, Loc);
15497
15498 ICEDiag D = CheckICE(this, Ctx);
15499 if (D.Kind != IK_ICE) {
15500 if (Loc) *Loc = D.Loc;
15501 return false;
15502 }
15503 return true;
15504}
15505
15506Optional<llvm::APSInt> Expr::getIntegerConstantExpr(const ASTContext &Ctx,
15507 SourceLocation *Loc,
15508 bool isEvaluated) const {
15509 if (isValueDependent()) {
15510 // Expression evaluator can't succeed on a dependent expression.
15511 return None;
15512 }
15513
15514 APSInt Value;
15515
15516 if (Ctx.getLangOpts().CPlusPlus11) {
15517 if (EvaluateCPlusPlus11IntegralConstantExpr(Ctx, this, &Value, Loc))
15518 return Value;
15519 return None;
15520 }
15521
15522 if (!isIntegerConstantExpr(Ctx, Loc))
15523 return None;
15524
15525 // The only possible side-effects here are due to UB discovered in the
15526 // evaluation (for instance, INT_MAX + 1). In such a case, we are still
15527 // required to treat the expression as an ICE, so we produce the folded
15528 // value.
15529 EvalResult ExprResult;
15530 Expr::EvalStatus Status;
15531 EvalInfo Info(Ctx, Status, EvalInfo::EM_IgnoreSideEffects);
15532 Info.InConstantContext = true;
15533
15534 if (!::EvaluateAsInt(this, ExprResult, Ctx, SE_AllowSideEffects, Info))
15535 llvm_unreachable("ICE cannot be evaluated!")::llvm::llvm_unreachable_internal("ICE cannot be evaluated!",
"/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15535)
;
15536
15537 return ExprResult.Val.getInt();
15538}
15539
15540bool Expr::isCXX98IntegralConstantExpr(const ASTContext &Ctx) const {
15541 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15542, __extension__ __PRETTY_FUNCTION__))
15542 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15542, __extension__ __PRETTY_FUNCTION__))
;
15543
15544 return CheckICE(this, Ctx).Kind == IK_ICE;
15545}
15546
15547bool Expr::isCXX11ConstantExpr(const ASTContext &Ctx, APValue *Result,
15548 SourceLocation *Loc) const {
15549 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15550, __extension__ __PRETTY_FUNCTION__))
15550 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15550, __extension__ __PRETTY_FUNCTION__))
;
15551
15552 // We support this checking in C++98 mode in order to diagnose compatibility
15553 // issues.
15554 assert(Ctx.getLangOpts().CPlusPlus)(static_cast <bool> (Ctx.getLangOpts().CPlusPlus) ? void
(0) : __assert_fail ("Ctx.getLangOpts().CPlusPlus", "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15554, __extension__ __PRETTY_FUNCTION__))
;
15555
15556 // Build evaluation settings.
15557 Expr::EvalStatus Status;
15558 SmallVector<PartialDiagnosticAt, 8> Diags;
15559 Status.Diag = &Diags;
15560 EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpression);
15561
15562 APValue Scratch;
15563 bool IsConstExpr =
15564 ::EvaluateAsRValue(Info, this, Result ? *Result : Scratch) &&
15565 // FIXME: We don't produce a diagnostic for this, but the callers that
15566 // call us on arbitrary full-expressions should generally not care.
15567 Info.discardCleanups() && !Status.HasSideEffects;
15568
15569 if (!Diags.empty()) {
15570 IsConstExpr = false;
15571 if (Loc) *Loc = Diags[0].first;
15572 } else if (!IsConstExpr) {
15573 // FIXME: This shouldn't happen.
15574 if (Loc) *Loc = getExprLoc();
15575 }
15576
15577 return IsConstExpr;
15578}
15579
15580bool Expr::EvaluateWithSubstitution(APValue &Value, ASTContext &Ctx,
15581 const FunctionDecl *Callee,
15582 ArrayRef<const Expr*> Args,
15583 const Expr *This) const {
15584 assert(!isValueDependent() &&(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15585, __extension__ __PRETTY_FUNCTION__))
15585 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!isValueDependent() && "Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15585, __extension__ __PRETTY_FUNCTION__))
;
15586
15587 Expr::EvalStatus Status;
15588 EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantExpressionUnevaluated);
15589 Info.InConstantContext = true;
15590
15591 LValue ThisVal;
15592 const LValue *ThisPtr = nullptr;
15593 if (This) {
15594#ifndef NDEBUG
15595 auto *MD = dyn_cast<CXXMethodDecl>(Callee);
15596 assert(MD && "Don't provide `this` for non-methods.")(static_cast <bool> (MD && "Don't provide `this` for non-methods."
) ? void (0) : __assert_fail ("MD && \"Don't provide `this` for non-methods.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15596, __extension__ __PRETTY_FUNCTION__))
;
15597 assert(!MD->isStatic() && "Don't provide `this` for static methods.")(static_cast <bool> (!MD->isStatic() && "Don't provide `this` for static methods."
) ? void (0) : __assert_fail ("!MD->isStatic() && \"Don't provide `this` for static methods.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15597, __extension__ __PRETTY_FUNCTION__))
;
15598#endif
15599 if (!This->isValueDependent() &&
15600 EvaluateObjectArgument(Info, This, ThisVal) &&
15601 !Info.EvalStatus.HasSideEffects)
15602 ThisPtr = &ThisVal;
15603
15604 // Ignore any side-effects from a failed evaluation. This is safe because
15605 // they can't interfere with any other argument evaluation.
15606 Info.EvalStatus.HasSideEffects = false;
15607 }
15608
15609 CallRef Call = Info.CurrentCall->createCall(Callee);
15610 for (ArrayRef<const Expr*>::iterator I = Args.begin(), E = Args.end();
15611 I != E; ++I) {
15612 unsigned Idx = I - Args.begin();
15613 if (Idx >= Callee->getNumParams())
15614 break;
15615 const ParmVarDecl *PVD = Callee->getParamDecl(Idx);
15616 if ((*I)->isValueDependent() ||
15617 !EvaluateCallArg(PVD, *I, Call, Info) ||
15618 Info.EvalStatus.HasSideEffects) {
15619 // If evaluation fails, throw away the argument entirely.
15620 if (APValue *Slot = Info.getParamSlot(Call, PVD))
15621 *Slot = APValue();
15622 }
15623
15624 // Ignore any side-effects from a failed evaluation. This is safe because
15625 // they can't interfere with any other argument evaluation.
15626 Info.EvalStatus.HasSideEffects = false;
15627 }
15628
15629 // Parameter cleanups happen in the caller and are not part of this
15630 // evaluation.
15631 Info.discardCleanups();
15632 Info.EvalStatus.HasSideEffects = false;
15633
15634 // Build fake call to Callee.
15635 CallStackFrame Frame(Info, Callee->getLocation(), Callee, ThisPtr, Call);
15636 // FIXME: Missing ExprWithCleanups in enable_if conditions?
15637 FullExpressionRAII Scope(Info);
15638 return Evaluate(Value, Info, this) && Scope.destroy() &&
15639 !Info.EvalStatus.HasSideEffects;
15640}
15641
15642bool Expr::isPotentialConstantExpr(const FunctionDecl *FD,
15643 SmallVectorImpl<
15644 PartialDiagnosticAt> &Diags) {
15645 // FIXME: It would be useful to check constexpr function templates, but at the
15646 // moment the constant expression evaluator cannot cope with the non-rigorous
15647 // ASTs which we build for dependent expressions.
15648 if (FD->isDependentContext())
15649 return true;
15650
15651 Expr::EvalStatus Status;
15652 Status.Diag = &Diags;
15653
15654 EvalInfo Info(FD->getASTContext(), Status, EvalInfo::EM_ConstantExpression);
15655 Info.InConstantContext = true;
15656 Info.CheckingPotentialConstantExpression = true;
15657
15658 // The constexpr VM attempts to compile all methods to bytecode here.
15659 if (Info.EnableNewConstInterp) {
15660 Info.Ctx.getInterpContext().isPotentialConstantExpr(Info, FD);
15661 return Diags.empty();
15662 }
15663
15664 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
15665 const CXXRecordDecl *RD = MD ? MD->getParent()->getCanonicalDecl() : nullptr;
15666
15667 // Fabricate an arbitrary expression on the stack and pretend that it
15668 // is a temporary being used as the 'this' pointer.
15669 LValue This;
15670 ImplicitValueInitExpr VIE(RD ? Info.Ctx.getRecordType(RD) : Info.Ctx.IntTy);
15671 This.set({&VIE, Info.CurrentCall->Index});
15672
15673 ArrayRef<const Expr*> Args;
15674
15675 APValue Scratch;
15676 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) {
15677 // Evaluate the call as a constant initializer, to allow the construction
15678 // of objects of non-literal types.
15679 Info.setEvaluatingDecl(This.getLValueBase(), Scratch);
15680 HandleConstructorCall(&VIE, This, Args, CD, Info, Scratch);
15681 } else {
15682 SourceLocation Loc = FD->getLocation();
15683 HandleFunctionCall(Loc, FD, (MD && MD->isInstance()) ? &This : nullptr,
15684 Args, CallRef(), FD->getBody(), Info, Scratch, nullptr);
15685 }
15686
15687 return Diags.empty();
15688}
15689
15690bool Expr::isPotentialConstantExprUnevaluated(Expr *E,
15691 const FunctionDecl *FD,
15692 SmallVectorImpl<
15693 PartialDiagnosticAt> &Diags) {
15694 assert(!E->isValueDependent() &&(static_cast <bool> (!E->isValueDependent() &&
"Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!E->isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15695, __extension__ __PRETTY_FUNCTION__))
15695 "Expression evaluator can't be called on a dependent expression.")(static_cast <bool> (!E->isValueDependent() &&
"Expression evaluator can't be called on a dependent expression."
) ? void (0) : __assert_fail ("!E->isValueDependent() && \"Expression evaluator can't be called on a dependent expression.\""
, "/build/llvm-toolchain-snapshot-14~++20211110111138+cffbfd01e37b/clang/lib/AST/ExprConstant.cpp"
, 15695, __extension__ __PRETTY_FUNCTION__))
;
15696
15697 Expr::EvalStatus Status;
15698 Status.Diag = &Diags;
15699
15700 EvalInfo Info(FD->getASTContext(), Status,
15701 EvalInfo::EM_ConstantExpressionUnevaluated);
15702 Info.InConstantContext = true;
15703 Info.CheckingPotentialConstantExpression = true;
15704
15705 // Fabricate a call stack frame to give the arguments a plausible cover story.
15706 CallStackFrame Frame(Info, SourceLocation(), FD, /*This*/ nullptr, CallRef());
15707
15708 APValue ResultScratch;
15709 Evaluate(ResultScratch, Info, E);
15710 return Diags.empty();
15711}
15712
15713bool Expr::tryEvaluateObjectSize(uint64_t &Result, ASTContext &Ctx,
15714 unsigned Type) const {
15715 if (!getType()->isPointerType())
15716 return false;
15717
15718 Expr::EvalStatus Status;
15719 EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantFold);
15720 return tryEvaluateBuiltinObjectSize(this, Type, Info, Result);
15721}
15722
15723static bool EvaluateBuiltinStrLen(const Expr *E, uint64_t &Result,
15724 EvalInfo &Info) {
15725 if (!E->getType()->hasPointerRepresentation() || !E->isPRValue())
15726 return false;
15727
15728 LValue String;
15729
15730 if (!EvaluatePointer(E, String, Info))
15731 return false;
15732
15733 QualType CharTy = E->getType()->getPointeeType();
15734
15735 // Fast path: if it's a string literal, search the string value.
15736 if (const StringLiteral *S = dyn_cast_or_null<StringLiteral>(
15737 String.getLValueBase().dyn_cast<const Expr *>())) {
15738 StringRef Str = S->getBytes();
15739 int64_t Off = String.Offset.getQuantity();
15740 if (Off >= 0 && (uint64_t)Off <= (uint64_t)Str.size() &&
15741 S->getCharByteWidth() == 1 &&
15742 // FIXME: Add fast-path for wchar_t too.
15743 Info.Ctx.hasSameUnqualifiedType(CharTy, Info.Ctx.CharTy)) {
15744 Str = Str.substr(Off);
15745
15746 StringRef::size_type Pos = Str.find(0);
15747 if (Pos != StringRef::npos)
15748 Str = Str.substr(0, Pos);
15749
15750 Result = Str.size();
15751 return true;
15752 }
15753
15754 // Fall through to slow path.
15755 }
15756
15757 // Slow path: scan the bytes of the string looking for the terminating 0.
15758 for (uint64_t Strlen = 0; /**/; ++Strlen) {
15759 APValue Char;
15760 if (!handleLValueToRValueConversion(Info, E, CharTy, String, Char) ||
15761 !Char.isInt())
15762 return false;
15763 if (!Char.getInt()) {
15764 Result = Strlen;
15765 return true;
15766 }
15767 if (!HandleLValueArrayAdjustment(Info, E, String, CharTy, 1))
15768 return false;
15769 }
15770}
15771
15772bool Expr::tryEvaluateStrLen(uint64_t &Result, ASTContext &Ctx) const {
15773 Expr::EvalStatus Status;
15774 EvalInfo Info(Ctx, Status, EvalInfo::EM_ConstantFold);
15775 return EvaluateBuiltinStrLen(this, Result, Info);
15776}