1 //===--- CGExprCXX.cpp - Emit LLVM Code for C++ expressions ---------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This contains code dealing with code generation of C++ expressions
12 //===----------------------------------------------------------------------===//
14 #include "CodeGenFunction.h"
15 #include "CGCUDARuntime.h"
17 #include "CGDebugInfo.h"
18 #include "CGObjCRuntime.h"
19 #include "ConstantEmitter.h"
20 #include "clang/CodeGen/CGFunctionInfo.h"
21 #include "clang/Frontend/CodeGenOptions.h"
22 #include "llvm/IR/CallSite.h"
23 #include "llvm/IR/Intrinsics.h"
25 using namespace clang;
26 using namespace CodeGen;
29 struct MemberCallInfo {
31 // Number of prefix arguments for the call. Ignores the `this` pointer.
37 commonEmitCXXMemberOrOperatorCall(CodeGenFunction &CGF, const CXXMethodDecl *MD,
38 llvm::Value *This, llvm::Value *ImplicitParam,
39 QualType ImplicitParamTy, const CallExpr *CE,
40 CallArgList &Args, CallArgList *RtlArgs) {
41 assert(CE == nullptr || isa<CXXMemberCallExpr>(CE) ||
42 isa<CXXOperatorCallExpr>(CE));
43 assert(MD->isInstance() &&
44 "Trying to emit a member or operator call expr on a static method!");
45 ASTContext &C = CGF.getContext();
48 const CXXRecordDecl *RD =
49 CGF.CGM.getCXXABI().getThisArgumentTypeForMethod(MD);
50 Args.add(RValue::get(This),
51 RD ? C.getPointerType(C.getTypeDeclType(RD)) : C.VoidPtrTy);
53 // If there is an implicit parameter (e.g. VTT), emit it.
55 Args.add(RValue::get(ImplicitParam), ImplicitParamTy);
58 const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
59 RequiredArgs required = RequiredArgs::forPrototypePlus(FPT, Args.size(), MD);
60 unsigned PrefixSize = Args.size() - 1;
62 // And the rest of the call args.
64 // Special case: if the caller emitted the arguments right-to-left already
65 // (prior to emitting the *this argument), we're done. This happens for
66 // assignment operators.
67 Args.addFrom(*RtlArgs);
69 // Special case: skip first argument of CXXOperatorCall (it is "this").
70 unsigned ArgsToSkip = isa<CXXOperatorCallExpr>(CE) ? 1 : 0;
71 CGF.EmitCallArgs(Args, FPT, drop_begin(CE->arguments(), ArgsToSkip),
72 CE->getDirectCallee());
75 FPT->getNumParams() == 0 &&
76 "No CallExpr specified for function with non-zero number of arguments");
78 return {required, PrefixSize};
81 RValue CodeGenFunction::EmitCXXMemberOrOperatorCall(
82 const CXXMethodDecl *MD, const CGCallee &Callee,
83 ReturnValueSlot ReturnValue,
84 llvm::Value *This, llvm::Value *ImplicitParam, QualType ImplicitParamTy,
85 const CallExpr *CE, CallArgList *RtlArgs) {
86 const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
88 MemberCallInfo CallInfo = commonEmitCXXMemberOrOperatorCall(
89 *this, MD, This, ImplicitParam, ImplicitParamTy, CE, Args, RtlArgs);
90 auto &FnInfo = CGM.getTypes().arrangeCXXMethodCall(
91 Args, FPT, CallInfo.ReqArgs, CallInfo.PrefixSize);
92 return EmitCall(FnInfo, Callee, ReturnValue, Args, nullptr,
93 CE ? CE->getExprLoc() : SourceLocation());
96 RValue CodeGenFunction::EmitCXXDestructorCall(
97 const CXXDestructorDecl *DD, const CGCallee &Callee, llvm::Value *This,
98 llvm::Value *ImplicitParam, QualType ImplicitParamTy, const CallExpr *CE,
101 commonEmitCXXMemberOrOperatorCall(*this, DD, This, ImplicitParam,
102 ImplicitParamTy, CE, Args, nullptr);
103 return EmitCall(CGM.getTypes().arrangeCXXStructorDeclaration(DD, Type),
104 Callee, ReturnValueSlot(), Args);
107 RValue CodeGenFunction::EmitCXXPseudoDestructorExpr(
108 const CXXPseudoDestructorExpr *E) {
109 QualType DestroyedType = E->getDestroyedType();
110 if (DestroyedType.hasStrongOrWeakObjCLifetime()) {
111 // Automatic Reference Counting:
112 // If the pseudo-expression names a retainable object with weak or
113 // strong lifetime, the object shall be released.
114 Expr *BaseExpr = E->getBase();
115 Address BaseValue = Address::invalid();
116 Qualifiers BaseQuals;
118 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
120 BaseValue = EmitPointerWithAlignment(BaseExpr);
121 const PointerType *PTy = BaseExpr->getType()->getAs<PointerType>();
122 BaseQuals = PTy->getPointeeType().getQualifiers();
124 LValue BaseLV = EmitLValue(BaseExpr);
125 BaseValue = BaseLV.getAddress();
126 QualType BaseTy = BaseExpr->getType();
127 BaseQuals = BaseTy.getQualifiers();
130 switch (DestroyedType.getObjCLifetime()) {
131 case Qualifiers::OCL_None:
132 case Qualifiers::OCL_ExplicitNone:
133 case Qualifiers::OCL_Autoreleasing:
136 case Qualifiers::OCL_Strong:
137 EmitARCRelease(Builder.CreateLoad(BaseValue,
138 DestroyedType.isVolatileQualified()),
142 case Qualifiers::OCL_Weak:
143 EmitARCDestroyWeak(BaseValue);
147 // C++ [expr.pseudo]p1:
148 // The result shall only be used as the operand for the function call
149 // operator (), and the result of such a call has type void. The only
150 // effect is the evaluation of the postfix-expression before the dot or
152 EmitIgnoredExpr(E->getBase());
155 return RValue::get(nullptr);
158 static CXXRecordDecl *getCXXRecord(const Expr *E) {
159 QualType T = E->getType();
160 if (const PointerType *PTy = T->getAs<PointerType>())
161 T = PTy->getPointeeType();
162 const RecordType *Ty = T->castAs<RecordType>();
163 return cast<CXXRecordDecl>(Ty->getDecl());
166 // Note: This function also emit constructor calls to support a MSVC
167 // extensions allowing explicit constructor function call.
168 RValue CodeGenFunction::EmitCXXMemberCallExpr(const CXXMemberCallExpr *CE,
169 ReturnValueSlot ReturnValue) {
170 const Expr *callee = CE->getCallee()->IgnoreParens();
172 if (isa<BinaryOperator>(callee))
173 return EmitCXXMemberPointerCallExpr(CE, ReturnValue);
175 const MemberExpr *ME = cast<MemberExpr>(callee);
176 const CXXMethodDecl *MD = cast<CXXMethodDecl>(ME->getMemberDecl());
178 if (MD->isStatic()) {
179 // The method is static, emit it as we would a regular call.
180 CGCallee callee = CGCallee::forDirect(CGM.GetAddrOfFunction(MD), MD);
181 return EmitCall(getContext().getPointerType(MD->getType()), callee, CE,
185 bool HasQualifier = ME->hasQualifier();
186 NestedNameSpecifier *Qualifier = HasQualifier ? ME->getQualifier() : nullptr;
187 bool IsArrow = ME->isArrow();
188 const Expr *Base = ME->getBase();
190 return EmitCXXMemberOrOperatorMemberCallExpr(
191 CE, MD, ReturnValue, HasQualifier, Qualifier, IsArrow, Base);
194 RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
195 const CallExpr *CE, const CXXMethodDecl *MD, ReturnValueSlot ReturnValue,
196 bool HasQualifier, NestedNameSpecifier *Qualifier, bool IsArrow,
198 assert(isa<CXXMemberCallExpr>(CE) || isa<CXXOperatorCallExpr>(CE));
200 // Compute the object pointer.
201 bool CanUseVirtualCall = MD->isVirtual() && !HasQualifier;
203 const CXXMethodDecl *DevirtualizedMethod = nullptr;
204 if (CanUseVirtualCall &&
205 MD->getDevirtualizedMethod(Base, getLangOpts().AppleKext)) {
206 const CXXRecordDecl *BestDynamicDecl = Base->getBestDynamicClassType();
207 DevirtualizedMethod = MD->getCorrespondingMethodInClass(BestDynamicDecl);
208 assert(DevirtualizedMethod);
209 const CXXRecordDecl *DevirtualizedClass = DevirtualizedMethod->getParent();
210 const Expr *Inner = Base->ignoreParenBaseCasts();
211 if (DevirtualizedMethod->getReturnType().getCanonicalType() !=
212 MD->getReturnType().getCanonicalType())
213 // If the return types are not the same, this might be a case where more
214 // code needs to run to compensate for it. For example, the derived
215 // method might return a type that inherits form from the return
216 // type of MD and has a prefix.
217 // For now we just avoid devirtualizing these covariant cases.
218 DevirtualizedMethod = nullptr;
219 else if (getCXXRecord(Inner) == DevirtualizedClass)
220 // If the class of the Inner expression is where the dynamic method
221 // is defined, build the this pointer from it.
223 else if (getCXXRecord(Base) != DevirtualizedClass) {
224 // If the method is defined in a class that is not the best dynamic
225 // one or the one of the full expression, we would have to build
226 // a derived-to-base cast to compute the correct this pointer, but
227 // we don't have support for that yet, so do a virtual call.
228 DevirtualizedMethod = nullptr;
232 // C++17 demands that we evaluate the RHS of a (possibly-compound) assignment
233 // operator before the LHS.
234 CallArgList RtlArgStorage;
235 CallArgList *RtlArgs = nullptr;
236 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(CE)) {
237 if (OCE->isAssignmentOp()) {
238 RtlArgs = &RtlArgStorage;
239 EmitCallArgs(*RtlArgs, MD->getType()->castAs<FunctionProtoType>(),
240 drop_begin(CE->arguments(), 1), CE->getDirectCallee(),
241 /*ParamsToSkip*/0, EvaluationOrder::ForceRightToLeft);
247 LValueBaseInfo BaseInfo;
248 TBAAAccessInfo TBAAInfo;
249 Address ThisValue = EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo);
250 This = MakeAddrLValue(ThisValue, Base->getType(), BaseInfo, TBAAInfo);
252 This = EmitLValue(Base);
256 if (MD->isTrivial() || (MD->isDefaulted() && MD->getParent()->isUnion())) {
257 if (isa<CXXDestructorDecl>(MD)) return RValue::get(nullptr);
258 if (isa<CXXConstructorDecl>(MD) &&
259 cast<CXXConstructorDecl>(MD)->isDefaultConstructor())
260 return RValue::get(nullptr);
262 if (!MD->getParent()->mayInsertExtraPadding()) {
263 if (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator()) {
264 // We don't like to generate the trivial copy/move assignment operator
265 // when it isn't necessary; just produce the proper effect here.
266 LValue RHS = isa<CXXOperatorCallExpr>(CE)
267 ? MakeNaturalAlignAddrLValue(
268 (*RtlArgs)[0].getRValue(*this).getScalarVal(),
269 (*(CE->arg_begin() + 1))->getType())
270 : EmitLValue(*CE->arg_begin());
271 EmitAggregateAssign(This, RHS, CE->getType());
272 return RValue::get(This.getPointer());
275 if (isa<CXXConstructorDecl>(MD) &&
276 cast<CXXConstructorDecl>(MD)->isCopyOrMoveConstructor()) {
277 // Trivial move and copy ctor are the same.
278 assert(CE->getNumArgs() == 1 && "unexpected argcount for trivial ctor");
279 const Expr *Arg = *CE->arg_begin();
280 LValue RHS = EmitLValue(Arg);
281 LValue Dest = MakeAddrLValue(This.getAddress(), Arg->getType());
282 // This is the MSVC p->Ctor::Ctor(...) extension. We assume that's
283 // constructing a new complete object of type Ctor.
284 EmitAggregateCopy(Dest, RHS, Arg->getType(),
285 AggValueSlot::DoesNotOverlap);
286 return RValue::get(This.getPointer());
288 llvm_unreachable("unknown trivial member function");
292 // Compute the function type we're calling.
293 const CXXMethodDecl *CalleeDecl =
294 DevirtualizedMethod ? DevirtualizedMethod : MD;
295 const CGFunctionInfo *FInfo = nullptr;
296 if (const auto *Dtor = dyn_cast<CXXDestructorDecl>(CalleeDecl))
297 FInfo = &CGM.getTypes().arrangeCXXStructorDeclaration(
298 Dtor, StructorType::Complete);
299 else if (const auto *Ctor = dyn_cast<CXXConstructorDecl>(CalleeDecl))
300 FInfo = &CGM.getTypes().arrangeCXXStructorDeclaration(
301 Ctor, StructorType::Complete);
303 FInfo = &CGM.getTypes().arrangeCXXMethodDeclaration(CalleeDecl);
305 llvm::FunctionType *Ty = CGM.getTypes().GetFunctionType(*FInfo);
307 // C++11 [class.mfct.non-static]p2:
308 // If a non-static member function of a class X is called for an object that
309 // is not of type X, or of a type derived from X, the behavior is undefined.
310 SourceLocation CallLoc;
311 ASTContext &C = getContext();
313 CallLoc = CE->getExprLoc();
315 SanitizerSet SkippedChecks;
316 if (const auto *CMCE = dyn_cast<CXXMemberCallExpr>(CE)) {
317 auto *IOA = CMCE->getImplicitObjectArgument();
318 bool IsImplicitObjectCXXThis = IsWrappedCXXThis(IOA);
319 if (IsImplicitObjectCXXThis)
320 SkippedChecks.set(SanitizerKind::Alignment, true);
321 if (IsImplicitObjectCXXThis || isa<DeclRefExpr>(IOA))
322 SkippedChecks.set(SanitizerKind::Null, true);
325 isa<CXXConstructorDecl>(CalleeDecl) ? CodeGenFunction::TCK_ConstructorCall
326 : CodeGenFunction::TCK_MemberCall,
327 CallLoc, This.getPointer(), C.getRecordType(CalleeDecl->getParent()),
328 /*Alignment=*/CharUnits::Zero(), SkippedChecks);
330 // FIXME: Uses of 'MD' past this point need to be audited. We may need to use
331 // 'CalleeDecl' instead.
333 // C++ [class.virtual]p12:
334 // Explicit qualification with the scope operator (5.1) suppresses the
335 // virtual call mechanism.
337 // We also don't emit a virtual call if the base expression has a record type
338 // because then we know what the type is.
339 bool UseVirtualCall = CanUseVirtualCall && !DevirtualizedMethod;
341 if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(MD)) {
342 assert(CE->arg_begin() == CE->arg_end() &&
343 "Destructor shouldn't have explicit parameters");
344 assert(ReturnValue.isNull() && "Destructor shouldn't have return value");
345 if (UseVirtualCall) {
346 CGM.getCXXABI().EmitVirtualDestructorCall(
347 *this, Dtor, Dtor_Complete, This.getAddress(),
348 cast<CXXMemberCallExpr>(CE));
351 if (getLangOpts().AppleKext && MD->isVirtual() && HasQualifier)
352 Callee = BuildAppleKextVirtualCall(MD, Qualifier, Ty);
353 else if (!DevirtualizedMethod)
354 Callee = CGCallee::forDirect(
355 CGM.getAddrOfCXXStructor(Dtor, StructorType::Complete, FInfo, Ty),
358 const CXXDestructorDecl *DDtor =
359 cast<CXXDestructorDecl>(DevirtualizedMethod);
360 Callee = CGCallee::forDirect(
361 CGM.GetAddrOfFunction(GlobalDecl(DDtor, Dtor_Complete), Ty),
364 EmitCXXMemberOrOperatorCall(
365 CalleeDecl, Callee, ReturnValue, This.getPointer(),
366 /*ImplicitParam=*/nullptr, QualType(), CE, nullptr);
368 return RValue::get(nullptr);
372 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) {
373 Callee = CGCallee::forDirect(
374 CGM.GetAddrOfFunction(GlobalDecl(Ctor, Ctor_Complete), Ty),
376 } else if (UseVirtualCall) {
377 Callee = CGCallee::forVirtual(CE, MD, This.getAddress(), Ty);
379 if (SanOpts.has(SanitizerKind::CFINVCall) &&
380 MD->getParent()->isDynamicClass()) {
382 const CXXRecordDecl *RD;
383 std::tie(VTable, RD) =
384 CGM.getCXXABI().LoadVTablePtr(*this, This.getAddress(),
386 EmitVTablePtrCheckForCall(RD, VTable, CFITCK_NVCall, CE->getLocStart());
389 if (getLangOpts().AppleKext && MD->isVirtual() && HasQualifier)
390 Callee = BuildAppleKextVirtualCall(MD, Qualifier, Ty);
391 else if (!DevirtualizedMethod)
392 Callee = CGCallee::forDirect(CGM.GetAddrOfFunction(MD, Ty), MD);
394 Callee = CGCallee::forDirect(
395 CGM.GetAddrOfFunction(DevirtualizedMethod, Ty),
396 DevirtualizedMethod);
400 if (MD->isVirtual()) {
401 Address NewThisAddr =
402 CGM.getCXXABI().adjustThisArgumentForVirtualFunctionCall(
403 *this, CalleeDecl, This.getAddress(), UseVirtualCall);
404 This.setAddress(NewThisAddr);
407 return EmitCXXMemberOrOperatorCall(
408 CalleeDecl, Callee, ReturnValue, This.getPointer(),
409 /*ImplicitParam=*/nullptr, QualType(), CE, RtlArgs);
413 CodeGenFunction::EmitCXXMemberPointerCallExpr(const CXXMemberCallExpr *E,
414 ReturnValueSlot ReturnValue) {
415 const BinaryOperator *BO =
416 cast<BinaryOperator>(E->getCallee()->IgnoreParens());
417 const Expr *BaseExpr = BO->getLHS();
418 const Expr *MemFnExpr = BO->getRHS();
420 const MemberPointerType *MPT =
421 MemFnExpr->getType()->castAs<MemberPointerType>();
423 const FunctionProtoType *FPT =
424 MPT->getPointeeType()->castAs<FunctionProtoType>();
425 const CXXRecordDecl *RD =
426 cast<CXXRecordDecl>(MPT->getClass()->getAs<RecordType>()->getDecl());
428 // Emit the 'this' pointer.
429 Address This = Address::invalid();
430 if (BO->getOpcode() == BO_PtrMemI)
431 This = EmitPointerWithAlignment(BaseExpr);
433 This = EmitLValue(BaseExpr).getAddress();
435 EmitTypeCheck(TCK_MemberCall, E->getExprLoc(), This.getPointer(),
436 QualType(MPT->getClass(), 0));
438 // Get the member function pointer.
439 llvm::Value *MemFnPtr = EmitScalarExpr(MemFnExpr);
441 // Ask the ABI to load the callee. Note that This is modified.
442 llvm::Value *ThisPtrForCall = nullptr;
444 CGM.getCXXABI().EmitLoadOfMemberFunctionPointer(*this, BO, This,
445 ThisPtrForCall, MemFnPtr, MPT);
450 getContext().getPointerType(getContext().getTagDeclType(RD));
452 // Push the this ptr.
453 Args.add(RValue::get(ThisPtrForCall), ThisType);
455 RequiredArgs required =
456 RequiredArgs::forPrototypePlus(FPT, 1, /*FD=*/nullptr);
458 // And the rest of the call args
459 EmitCallArgs(Args, FPT, E->arguments());
460 return EmitCall(CGM.getTypes().arrangeCXXMethodCall(Args, FPT, required,
462 Callee, ReturnValue, Args, nullptr, E->getExprLoc());
466 CodeGenFunction::EmitCXXOperatorMemberCallExpr(const CXXOperatorCallExpr *E,
467 const CXXMethodDecl *MD,
468 ReturnValueSlot ReturnValue) {
469 assert(MD->isInstance() &&
470 "Trying to emit a member call expr on a static method!");
471 return EmitCXXMemberOrOperatorMemberCallExpr(
472 E, MD, ReturnValue, /*HasQualifier=*/false, /*Qualifier=*/nullptr,
473 /*IsArrow=*/false, E->getArg(0));
476 RValue CodeGenFunction::EmitCUDAKernelCallExpr(const CUDAKernelCallExpr *E,
477 ReturnValueSlot ReturnValue) {
478 return CGM.getCUDARuntime().EmitCUDAKernelCallExpr(*this, E, ReturnValue);
481 static void EmitNullBaseClassInitialization(CodeGenFunction &CGF,
483 const CXXRecordDecl *Base) {
487 DestPtr = CGF.Builder.CreateElementBitCast(DestPtr, CGF.Int8Ty);
489 const ASTRecordLayout &Layout = CGF.getContext().getASTRecordLayout(Base);
490 CharUnits NVSize = Layout.getNonVirtualSize();
492 // We cannot simply zero-initialize the entire base sub-object if vbptrs are
493 // present, they are initialized by the most derived class before calling the
495 SmallVector<std::pair<CharUnits, CharUnits>, 1> Stores;
496 Stores.emplace_back(CharUnits::Zero(), NVSize);
498 // Each store is split by the existence of a vbptr.
499 CharUnits VBPtrWidth = CGF.getPointerSize();
500 std::vector<CharUnits> VBPtrOffsets =
501 CGF.CGM.getCXXABI().getVBPtrOffsets(Base);
502 for (CharUnits VBPtrOffset : VBPtrOffsets) {
503 // Stop before we hit any virtual base pointers located in virtual bases.
504 if (VBPtrOffset >= NVSize)
506 std::pair<CharUnits, CharUnits> LastStore = Stores.pop_back_val();
507 CharUnits LastStoreOffset = LastStore.first;
508 CharUnits LastStoreSize = LastStore.second;
510 CharUnits SplitBeforeOffset = LastStoreOffset;
511 CharUnits SplitBeforeSize = VBPtrOffset - SplitBeforeOffset;
512 assert(!SplitBeforeSize.isNegative() && "negative store size!");
513 if (!SplitBeforeSize.isZero())
514 Stores.emplace_back(SplitBeforeOffset, SplitBeforeSize);
516 CharUnits SplitAfterOffset = VBPtrOffset + VBPtrWidth;
517 CharUnits SplitAfterSize = LastStoreSize - SplitAfterOffset;
518 assert(!SplitAfterSize.isNegative() && "negative store size!");
519 if (!SplitAfterSize.isZero())
520 Stores.emplace_back(SplitAfterOffset, SplitAfterSize);
523 // If the type contains a pointer to data member we can't memset it to zero.
524 // Instead, create a null constant and copy it to the destination.
525 // TODO: there are other patterns besides zero that we can usefully memset,
526 // like -1, which happens to be the pattern used by member-pointers.
527 // TODO: isZeroInitializable can be over-conservative in the case where a
528 // virtual base contains a member pointer.
529 llvm::Constant *NullConstantForBase = CGF.CGM.EmitNullConstantForBase(Base);
530 if (!NullConstantForBase->isNullValue()) {
531 llvm::GlobalVariable *NullVariable = new llvm::GlobalVariable(
532 CGF.CGM.getModule(), NullConstantForBase->getType(),
533 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage,
534 NullConstantForBase, Twine());
536 CharUnits Align = std::max(Layout.getNonVirtualAlignment(),
537 DestPtr.getAlignment());
538 NullVariable->setAlignment(Align.getQuantity());
540 Address SrcPtr = Address(CGF.EmitCastToVoidPtr(NullVariable), Align);
542 // Get and call the appropriate llvm.memcpy overload.
543 for (std::pair<CharUnits, CharUnits> Store : Stores) {
544 CharUnits StoreOffset = Store.first;
545 CharUnits StoreSize = Store.second;
546 llvm::Value *StoreSizeVal = CGF.CGM.getSize(StoreSize);
547 CGF.Builder.CreateMemCpy(
548 CGF.Builder.CreateConstInBoundsByteGEP(DestPtr, StoreOffset),
549 CGF.Builder.CreateConstInBoundsByteGEP(SrcPtr, StoreOffset),
553 // Otherwise, just memset the whole thing to zero. This is legal
554 // because in LLVM, all default initializers (other than the ones we just
555 // handled above) are guaranteed to have a bit pattern of all zeros.
557 for (std::pair<CharUnits, CharUnits> Store : Stores) {
558 CharUnits StoreOffset = Store.first;
559 CharUnits StoreSize = Store.second;
560 llvm::Value *StoreSizeVal = CGF.CGM.getSize(StoreSize);
561 CGF.Builder.CreateMemSet(
562 CGF.Builder.CreateConstInBoundsByteGEP(DestPtr, StoreOffset),
563 CGF.Builder.getInt8(0), StoreSizeVal);
569 CodeGenFunction::EmitCXXConstructExpr(const CXXConstructExpr *E,
571 assert(!Dest.isIgnored() && "Must have a destination!");
572 const CXXConstructorDecl *CD = E->getConstructor();
574 // If we require zero initialization before (or instead of) calling the
575 // constructor, as can be the case with a non-user-provided default
576 // constructor, emit the zero initialization now, unless destination is
578 if (E->requiresZeroInitialization() && !Dest.isZeroed()) {
579 switch (E->getConstructionKind()) {
580 case CXXConstructExpr::CK_Delegating:
581 case CXXConstructExpr::CK_Complete:
582 EmitNullInitialization(Dest.getAddress(), E->getType());
584 case CXXConstructExpr::CK_VirtualBase:
585 case CXXConstructExpr::CK_NonVirtualBase:
586 EmitNullBaseClassInitialization(*this, Dest.getAddress(),
592 // If this is a call to a trivial default constructor, do nothing.
593 if (CD->isTrivial() && CD->isDefaultConstructor())
596 // Elide the constructor if we're constructing from a temporary.
597 // The temporary check is required because Sema sets this on NRVO
599 if (getLangOpts().ElideConstructors && E->isElidable()) {
600 assert(getContext().hasSameUnqualifiedType(E->getType(),
601 E->getArg(0)->getType()));
602 if (E->getArg(0)->isTemporaryObject(getContext(), CD->getParent())) {
603 EmitAggExpr(E->getArg(0), Dest);
608 if (const ArrayType *arrayType
609 = getContext().getAsArrayType(E->getType())) {
610 EmitCXXAggrConstructorCall(CD, arrayType, Dest.getAddress(), E,
611 Dest.isSanitizerChecked());
613 CXXCtorType Type = Ctor_Complete;
614 bool ForVirtualBase = false;
615 bool Delegating = false;
617 switch (E->getConstructionKind()) {
618 case CXXConstructExpr::CK_Delegating:
619 // We should be emitting a constructor; GlobalDecl will assert this
620 Type = CurGD.getCtorType();
624 case CXXConstructExpr::CK_Complete:
625 Type = Ctor_Complete;
628 case CXXConstructExpr::CK_VirtualBase:
629 ForVirtualBase = true;
632 case CXXConstructExpr::CK_NonVirtualBase:
636 // Call the constructor.
637 EmitCXXConstructorCall(CD, Type, ForVirtualBase, Delegating,
638 Dest.getAddress(), E, Dest.mayOverlap(),
639 Dest.isSanitizerChecked());
643 void CodeGenFunction::EmitSynthesizedCXXCopyCtor(Address Dest, Address Src,
645 if (const ExprWithCleanups *E = dyn_cast<ExprWithCleanups>(Exp))
646 Exp = E->getSubExpr();
647 assert(isa<CXXConstructExpr>(Exp) &&
648 "EmitSynthesizedCXXCopyCtor - unknown copy ctor expr");
649 const CXXConstructExpr* E = cast<CXXConstructExpr>(Exp);
650 const CXXConstructorDecl *CD = E->getConstructor();
651 RunCleanupsScope Scope(*this);
653 // If we require zero initialization before (or instead of) calling the
654 // constructor, as can be the case with a non-user-provided default
655 // constructor, emit the zero initialization now.
656 // FIXME. Do I still need this for a copy ctor synthesis?
657 if (E->requiresZeroInitialization())
658 EmitNullInitialization(Dest, E->getType());
660 assert(!getContext().getAsConstantArrayType(E->getType())
661 && "EmitSynthesizedCXXCopyCtor - Copied-in Array");
662 EmitSynthesizedCXXCopyCtorCall(CD, Dest, Src, E);
665 static CharUnits CalculateCookiePadding(CodeGenFunction &CGF,
666 const CXXNewExpr *E) {
668 return CharUnits::Zero();
670 // No cookie is required if the operator new[] being used is the
671 // reserved placement operator new[].
672 if (E->getOperatorNew()->isReservedGlobalPlacementOperator())
673 return CharUnits::Zero();
675 return CGF.CGM.getCXXABI().GetArrayCookieSize(E);
678 static llvm::Value *EmitCXXNewAllocSize(CodeGenFunction &CGF,
680 unsigned minElements,
681 llvm::Value *&numElements,
682 llvm::Value *&sizeWithoutCookie) {
683 QualType type = e->getAllocatedType();
686 CharUnits typeSize = CGF.getContext().getTypeSizeInChars(type);
688 = llvm::ConstantInt::get(CGF.SizeTy, typeSize.getQuantity());
689 return sizeWithoutCookie;
692 // The width of size_t.
693 unsigned sizeWidth = CGF.SizeTy->getBitWidth();
695 // Figure out the cookie size.
696 llvm::APInt cookieSize(sizeWidth,
697 CalculateCookiePadding(CGF, e).getQuantity());
699 // Emit the array size expression.
700 // We multiply the size of all dimensions for NumElements.
701 // e.g for 'int[2][3]', ElemType is 'int' and NumElements is 6.
703 ConstantEmitter(CGF).tryEmitAbstract(e->getArraySize(), e->getType());
705 numElements = CGF.EmitScalarExpr(e->getArraySize());
706 assert(isa<llvm::IntegerType>(numElements->getType()));
708 // The number of elements can be have an arbitrary integer type;
709 // essentially, we need to multiply it by a constant factor, add a
710 // cookie size, and verify that the result is representable as a
711 // size_t. That's just a gloss, though, and it's wrong in one
712 // important way: if the count is negative, it's an error even if
713 // the cookie size would bring the total size >= 0.
715 = e->getArraySize()->getType()->isSignedIntegerOrEnumerationType();
716 llvm::IntegerType *numElementsType
717 = cast<llvm::IntegerType>(numElements->getType());
718 unsigned numElementsWidth = numElementsType->getBitWidth();
720 // Compute the constant factor.
721 llvm::APInt arraySizeMultiplier(sizeWidth, 1);
722 while (const ConstantArrayType *CAT
723 = CGF.getContext().getAsConstantArrayType(type)) {
724 type = CAT->getElementType();
725 arraySizeMultiplier *= CAT->getSize();
728 CharUnits typeSize = CGF.getContext().getTypeSizeInChars(type);
729 llvm::APInt typeSizeMultiplier(sizeWidth, typeSize.getQuantity());
730 typeSizeMultiplier *= arraySizeMultiplier;
732 // This will be a size_t.
735 // If someone is doing 'new int[42]' there is no need to do a dynamic check.
736 // Don't bloat the -O0 code.
737 if (llvm::ConstantInt *numElementsC =
738 dyn_cast<llvm::ConstantInt>(numElements)) {
739 const llvm::APInt &count = numElementsC->getValue();
741 bool hasAnyOverflow = false;
743 // If 'count' was a negative number, it's an overflow.
744 if (isSigned && count.isNegative())
745 hasAnyOverflow = true;
747 // We want to do all this arithmetic in size_t. If numElements is
748 // wider than that, check whether it's already too big, and if so,
750 else if (numElementsWidth > sizeWidth &&
751 numElementsWidth - sizeWidth > count.countLeadingZeros())
752 hasAnyOverflow = true;
754 // Okay, compute a count at the right width.
755 llvm::APInt adjustedCount = count.zextOrTrunc(sizeWidth);
757 // If there is a brace-initializer, we cannot allocate fewer elements than
758 // there are initializers. If we do, that's treated like an overflow.
759 if (adjustedCount.ult(minElements))
760 hasAnyOverflow = true;
762 // Scale numElements by that. This might overflow, but we don't
763 // care because it only overflows if allocationSize does, too, and
764 // if that overflows then we shouldn't use this.
765 numElements = llvm::ConstantInt::get(CGF.SizeTy,
766 adjustedCount * arraySizeMultiplier);
768 // Compute the size before cookie, and track whether it overflowed.
770 llvm::APInt allocationSize
771 = adjustedCount.umul_ov(typeSizeMultiplier, overflow);
772 hasAnyOverflow |= overflow;
774 // Add in the cookie, and check whether it's overflowed.
775 if (cookieSize != 0) {
776 // Save the current size without a cookie. This shouldn't be
777 // used if there was overflow.
778 sizeWithoutCookie = llvm::ConstantInt::get(CGF.SizeTy, allocationSize);
780 allocationSize = allocationSize.uadd_ov(cookieSize, overflow);
781 hasAnyOverflow |= overflow;
784 // On overflow, produce a -1 so operator new will fail.
785 if (hasAnyOverflow) {
786 size = llvm::Constant::getAllOnesValue(CGF.SizeTy);
788 size = llvm::ConstantInt::get(CGF.SizeTy, allocationSize);
791 // Otherwise, we might need to use the overflow intrinsics.
793 // There are up to five conditions we need to test for:
794 // 1) if isSigned, we need to check whether numElements is negative;
795 // 2) if numElementsWidth > sizeWidth, we need to check whether
796 // numElements is larger than something representable in size_t;
797 // 3) if minElements > 0, we need to check whether numElements is smaller
799 // 4) we need to compute
800 // sizeWithoutCookie := numElements * typeSizeMultiplier
801 // and check whether it overflows; and
802 // 5) if we need a cookie, we need to compute
803 // size := sizeWithoutCookie + cookieSize
804 // and check whether it overflows.
806 llvm::Value *hasOverflow = nullptr;
808 // If numElementsWidth > sizeWidth, then one way or another, we're
809 // going to have to do a comparison for (2), and this happens to
810 // take care of (1), too.
811 if (numElementsWidth > sizeWidth) {
812 llvm::APInt threshold(numElementsWidth, 1);
813 threshold <<= sizeWidth;
815 llvm::Value *thresholdV
816 = llvm::ConstantInt::get(numElementsType, threshold);
818 hasOverflow = CGF.Builder.CreateICmpUGE(numElements, thresholdV);
819 numElements = CGF.Builder.CreateTrunc(numElements, CGF.SizeTy);
821 // Otherwise, if we're signed, we want to sext up to size_t.
822 } else if (isSigned) {
823 if (numElementsWidth < sizeWidth)
824 numElements = CGF.Builder.CreateSExt(numElements, CGF.SizeTy);
826 // If there's a non-1 type size multiplier, then we can do the
827 // signedness check at the same time as we do the multiply
828 // because a negative number times anything will cause an
829 // unsigned overflow. Otherwise, we have to do it here. But at least
830 // in this case, we can subsume the >= minElements check.
831 if (typeSizeMultiplier == 1)
832 hasOverflow = CGF.Builder.CreateICmpSLT(numElements,
833 llvm::ConstantInt::get(CGF.SizeTy, minElements));
835 // Otherwise, zext up to size_t if necessary.
836 } else if (numElementsWidth < sizeWidth) {
837 numElements = CGF.Builder.CreateZExt(numElements, CGF.SizeTy);
840 assert(numElements->getType() == CGF.SizeTy);
843 // Don't allow allocation of fewer elements than we have initializers.
845 hasOverflow = CGF.Builder.CreateICmpULT(numElements,
846 llvm::ConstantInt::get(CGF.SizeTy, minElements));
847 } else if (numElementsWidth > sizeWidth) {
848 // The other existing overflow subsumes this check.
849 // We do an unsigned comparison, since any signed value < -1 is
850 // taken care of either above or below.
851 hasOverflow = CGF.Builder.CreateOr(hasOverflow,
852 CGF.Builder.CreateICmpULT(numElements,
853 llvm::ConstantInt::get(CGF.SizeTy, minElements)));
859 // Multiply by the type size if necessary. This multiplier
860 // includes all the factors for nested arrays.
862 // This step also causes numElements to be scaled up by the
863 // nested-array factor if necessary. Overflow on this computation
864 // can be ignored because the result shouldn't be used if
866 if (typeSizeMultiplier != 1) {
867 llvm::Value *umul_with_overflow
868 = CGF.CGM.getIntrinsic(llvm::Intrinsic::umul_with_overflow, CGF.SizeTy);
871 llvm::ConstantInt::get(CGF.SizeTy, typeSizeMultiplier);
872 llvm::Value *result =
873 CGF.Builder.CreateCall(umul_with_overflow, {size, tsmV});
875 llvm::Value *overflowed = CGF.Builder.CreateExtractValue(result, 1);
877 hasOverflow = CGF.Builder.CreateOr(hasOverflow, overflowed);
879 hasOverflow = overflowed;
881 size = CGF.Builder.CreateExtractValue(result, 0);
883 // Also scale up numElements by the array size multiplier.
884 if (arraySizeMultiplier != 1) {
885 // If the base element type size is 1, then we can re-use the
886 // multiply we just did.
887 if (typeSize.isOne()) {
888 assert(arraySizeMultiplier == typeSizeMultiplier);
891 // Otherwise we need a separate multiply.
894 llvm::ConstantInt::get(CGF.SizeTy, arraySizeMultiplier);
895 numElements = CGF.Builder.CreateMul(numElements, asmV);
899 // numElements doesn't need to be scaled.
900 assert(arraySizeMultiplier == 1);
903 // Add in the cookie size if necessary.
904 if (cookieSize != 0) {
905 sizeWithoutCookie = size;
907 llvm::Value *uadd_with_overflow
908 = CGF.CGM.getIntrinsic(llvm::Intrinsic::uadd_with_overflow, CGF.SizeTy);
910 llvm::Value *cookieSizeV = llvm::ConstantInt::get(CGF.SizeTy, cookieSize);
911 llvm::Value *result =
912 CGF.Builder.CreateCall(uadd_with_overflow, {size, cookieSizeV});
914 llvm::Value *overflowed = CGF.Builder.CreateExtractValue(result, 1);
916 hasOverflow = CGF.Builder.CreateOr(hasOverflow, overflowed);
918 hasOverflow = overflowed;
920 size = CGF.Builder.CreateExtractValue(result, 0);
923 // If we had any possibility of dynamic overflow, make a select to
924 // overwrite 'size' with an all-ones value, which should cause
925 // operator new to throw.
927 size = CGF.Builder.CreateSelect(hasOverflow,
928 llvm::Constant::getAllOnesValue(CGF.SizeTy),
933 sizeWithoutCookie = size;
935 assert(sizeWithoutCookie && "didn't set sizeWithoutCookie?");
940 static void StoreAnyExprIntoOneUnit(CodeGenFunction &CGF, const Expr *Init,
941 QualType AllocType, Address NewPtr,
942 AggValueSlot::Overlap_t MayOverlap) {
943 // FIXME: Refactor with EmitExprAsInit.
944 switch (CGF.getEvaluationKind(AllocType)) {
946 CGF.EmitScalarInit(Init, nullptr,
947 CGF.MakeAddrLValue(NewPtr, AllocType), false);
950 CGF.EmitComplexExprIntoLValue(Init, CGF.MakeAddrLValue(NewPtr, AllocType),
953 case TEK_Aggregate: {
955 = AggValueSlot::forAddr(NewPtr, AllocType.getQualifiers(),
956 AggValueSlot::IsDestructed,
957 AggValueSlot::DoesNotNeedGCBarriers,
958 AggValueSlot::IsNotAliased,
959 MayOverlap, AggValueSlot::IsNotZeroed,
960 AggValueSlot::IsSanitizerChecked);
961 CGF.EmitAggExpr(Init, Slot);
965 llvm_unreachable("bad evaluation kind");
968 void CodeGenFunction::EmitNewArrayInitializer(
969 const CXXNewExpr *E, QualType ElementType, llvm::Type *ElementTy,
970 Address BeginPtr, llvm::Value *NumElements,
971 llvm::Value *AllocSizeWithoutCookie) {
972 // If we have a type with trivial initialization and no initializer,
973 // there's nothing to do.
974 if (!E->hasInitializer())
977 Address CurPtr = BeginPtr;
979 unsigned InitListElements = 0;
981 const Expr *Init = E->getInitializer();
982 Address EndOfInit = Address::invalid();
983 QualType::DestructionKind DtorKind = ElementType.isDestructedType();
984 EHScopeStack::stable_iterator Cleanup;
985 llvm::Instruction *CleanupDominator = nullptr;
987 CharUnits ElementSize = getContext().getTypeSizeInChars(ElementType);
988 CharUnits ElementAlign =
989 BeginPtr.getAlignment().alignmentOfArrayElement(ElementSize);
991 // Attempt to perform zero-initialization using memset.
992 auto TryMemsetInitialization = [&]() -> bool {
993 // FIXME: If the type is a pointer-to-data-member under the Itanium ABI,
994 // we can initialize with a memset to -1.
995 if (!CGM.getTypes().isZeroInitializable(ElementType))
998 // Optimization: since zero initialization will just set the memory
999 // to all zeroes, generate a single memset to do it in one shot.
1001 // Subtract out the size of any elements we've already initialized.
1002 auto *RemainingSize = AllocSizeWithoutCookie;
1003 if (InitListElements) {
1004 // We know this can't overflow; we check this when doing the allocation.
1005 auto *InitializedSize = llvm::ConstantInt::get(
1006 RemainingSize->getType(),
1007 getContext().getTypeSizeInChars(ElementType).getQuantity() *
1009 RemainingSize = Builder.CreateSub(RemainingSize, InitializedSize);
1012 // Create the memset.
1013 Builder.CreateMemSet(CurPtr, Builder.getInt8(0), RemainingSize, false);
1017 // If the initializer is an initializer list, first do the explicit elements.
1018 if (const InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
1019 // Initializing from a (braced) string literal is a special case; the init
1020 // list element does not initialize a (single) array element.
1021 if (ILE->isStringLiteralInit()) {
1022 // Initialize the initial portion of length equal to that of the string
1023 // literal. The allocation must be for at least this much; we emitted a
1024 // check for that earlier.
1026 AggValueSlot::forAddr(CurPtr, ElementType.getQualifiers(),
1027 AggValueSlot::IsDestructed,
1028 AggValueSlot::DoesNotNeedGCBarriers,
1029 AggValueSlot::IsNotAliased,
1030 AggValueSlot::DoesNotOverlap,
1031 AggValueSlot::IsNotZeroed,
1032 AggValueSlot::IsSanitizerChecked);
1033 EmitAggExpr(ILE->getInit(0), Slot);
1035 // Move past these elements.
1037 cast<ConstantArrayType>(ILE->getType()->getAsArrayTypeUnsafe())
1038 ->getSize().getZExtValue();
1040 Address(Builder.CreateInBoundsGEP(CurPtr.getPointer(),
1041 Builder.getSize(InitListElements),
1043 CurPtr.getAlignment().alignmentAtOffset(InitListElements *
1046 // Zero out the rest, if any remain.
1047 llvm::ConstantInt *ConstNum = dyn_cast<llvm::ConstantInt>(NumElements);
1048 if (!ConstNum || !ConstNum->equalsInt(InitListElements)) {
1049 bool OK = TryMemsetInitialization();
1051 assert(OK && "couldn't memset character type?");
1056 InitListElements = ILE->getNumInits();
1058 // If this is a multi-dimensional array new, we will initialize multiple
1059 // elements with each init list element.
1060 QualType AllocType = E->getAllocatedType();
1061 if (const ConstantArrayType *CAT = dyn_cast_or_null<ConstantArrayType>(
1062 AllocType->getAsArrayTypeUnsafe())) {
1063 ElementTy = ConvertTypeForMem(AllocType);
1064 CurPtr = Builder.CreateElementBitCast(CurPtr, ElementTy);
1065 InitListElements *= getContext().getConstantArrayElementCount(CAT);
1068 // Enter a partial-destruction Cleanup if necessary.
1069 if (needsEHCleanup(DtorKind)) {
1070 // In principle we could tell the Cleanup where we are more
1071 // directly, but the control flow can get so varied here that it
1072 // would actually be quite complex. Therefore we go through an
1074 EndOfInit = CreateTempAlloca(BeginPtr.getType(), getPointerAlign(),
1076 CleanupDominator = Builder.CreateStore(BeginPtr.getPointer(), EndOfInit);
1077 pushIrregularPartialArrayCleanup(BeginPtr.getPointer(), EndOfInit,
1078 ElementType, ElementAlign,
1079 getDestroyer(DtorKind));
1080 Cleanup = EHStack.stable_begin();
1083 CharUnits StartAlign = CurPtr.getAlignment();
1084 for (unsigned i = 0, e = ILE->getNumInits(); i != e; ++i) {
1085 // Tell the cleanup that it needs to destroy up to this
1086 // element. TODO: some of these stores can be trivially
1087 // observed to be unnecessary.
1088 if (EndOfInit.isValid()) {
1090 Builder.CreateBitCast(CurPtr.getPointer(), BeginPtr.getType());
1091 Builder.CreateStore(FinishedPtr, EndOfInit);
1093 // FIXME: If the last initializer is an incomplete initializer list for
1094 // an array, and we have an array filler, we can fold together the two
1095 // initialization loops.
1096 StoreAnyExprIntoOneUnit(*this, ILE->getInit(i),
1097 ILE->getInit(i)->getType(), CurPtr,
1098 AggValueSlot::DoesNotOverlap);
1099 CurPtr = Address(Builder.CreateInBoundsGEP(CurPtr.getPointer(),
1102 StartAlign.alignmentAtOffset((i + 1) * ElementSize));
1105 // The remaining elements are filled with the array filler expression.
1106 Init = ILE->getArrayFiller();
1108 // Extract the initializer for the individual array elements by pulling
1109 // out the array filler from all the nested initializer lists. This avoids
1110 // generating a nested loop for the initialization.
1111 while (Init && Init->getType()->isConstantArrayType()) {
1112 auto *SubILE = dyn_cast<InitListExpr>(Init);
1115 assert(SubILE->getNumInits() == 0 && "explicit inits in array filler?");
1116 Init = SubILE->getArrayFiller();
1119 // Switch back to initializing one base element at a time.
1120 CurPtr = Builder.CreateBitCast(CurPtr, BeginPtr.getType());
1123 // If all elements have already been initialized, skip any further
1125 llvm::ConstantInt *ConstNum = dyn_cast<llvm::ConstantInt>(NumElements);
1126 if (ConstNum && ConstNum->getZExtValue() <= InitListElements) {
1127 // If there was a Cleanup, deactivate it.
1128 if (CleanupDominator)
1129 DeactivateCleanupBlock(Cleanup, CleanupDominator);
1133 assert(Init && "have trailing elements to initialize but no initializer");
1135 // If this is a constructor call, try to optimize it out, and failing that
1136 // emit a single loop to initialize all remaining elements.
1137 if (const CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init)) {
1138 CXXConstructorDecl *Ctor = CCE->getConstructor();
1139 if (Ctor->isTrivial()) {
1140 // If new expression did not specify value-initialization, then there
1141 // is no initialization.
1142 if (!CCE->requiresZeroInitialization() || Ctor->getParent()->isEmpty())
1145 if (TryMemsetInitialization())
1149 // Store the new Cleanup position for irregular Cleanups.
1151 // FIXME: Share this cleanup with the constructor call emission rather than
1152 // having it create a cleanup of its own.
1153 if (EndOfInit.isValid())
1154 Builder.CreateStore(CurPtr.getPointer(), EndOfInit);
1156 // Emit a constructor call loop to initialize the remaining elements.
1157 if (InitListElements)
1158 NumElements = Builder.CreateSub(
1160 llvm::ConstantInt::get(NumElements->getType(), InitListElements));
1161 EmitCXXAggrConstructorCall(Ctor, NumElements, CurPtr, CCE,
1162 /*NewPointerIsChecked*/true,
1163 CCE->requiresZeroInitialization());
1167 // If this is value-initialization, we can usually use memset.
1168 ImplicitValueInitExpr IVIE(ElementType);
1169 if (isa<ImplicitValueInitExpr>(Init)) {
1170 if (TryMemsetInitialization())
1173 // Switch to an ImplicitValueInitExpr for the element type. This handles
1174 // only one case: multidimensional array new of pointers to members. In
1175 // all other cases, we already have an initializer for the array element.
1179 // At this point we should have found an initializer for the individual
1180 // elements of the array.
1181 assert(getContext().hasSameUnqualifiedType(ElementType, Init->getType()) &&
1182 "got wrong type of element to initialize");
1184 // If we have an empty initializer list, we can usually use memset.
1185 if (auto *ILE = dyn_cast<InitListExpr>(Init))
1186 if (ILE->getNumInits() == 0 && TryMemsetInitialization())
1189 // If we have a struct whose every field is value-initialized, we can
1190 // usually use memset.
1191 if (auto *ILE = dyn_cast<InitListExpr>(Init)) {
1192 if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) {
1193 if (RType->getDecl()->isStruct()) {
1194 unsigned NumElements = 0;
1195 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RType->getDecl()))
1196 NumElements = CXXRD->getNumBases();
1197 for (auto *Field : RType->getDecl()->fields())
1198 if (!Field->isUnnamedBitfield())
1200 // FIXME: Recurse into nested InitListExprs.
1201 if (ILE->getNumInits() == NumElements)
1202 for (unsigned i = 0, e = ILE->getNumInits(); i != e; ++i)
1203 if (!isa<ImplicitValueInitExpr>(ILE->getInit(i)))
1205 if (ILE->getNumInits() == NumElements && TryMemsetInitialization())
1211 // Create the loop blocks.
1212 llvm::BasicBlock *EntryBB = Builder.GetInsertBlock();
1213 llvm::BasicBlock *LoopBB = createBasicBlock("new.loop");
1214 llvm::BasicBlock *ContBB = createBasicBlock("new.loop.end");
1216 // Find the end of the array, hoisted out of the loop.
1217 llvm::Value *EndPtr =
1218 Builder.CreateInBoundsGEP(BeginPtr.getPointer(), NumElements, "array.end");
1220 // If the number of elements isn't constant, we have to now check if there is
1221 // anything left to initialize.
1223 llvm::Value *IsEmpty =
1224 Builder.CreateICmpEQ(CurPtr.getPointer(), EndPtr, "array.isempty");
1225 Builder.CreateCondBr(IsEmpty, ContBB, LoopBB);
1231 // Set up the current-element phi.
1232 llvm::PHINode *CurPtrPhi =
1233 Builder.CreatePHI(CurPtr.getType(), 2, "array.cur");
1234 CurPtrPhi->addIncoming(CurPtr.getPointer(), EntryBB);
1236 CurPtr = Address(CurPtrPhi, ElementAlign);
1238 // Store the new Cleanup position for irregular Cleanups.
1239 if (EndOfInit.isValid())
1240 Builder.CreateStore(CurPtr.getPointer(), EndOfInit);
1242 // Enter a partial-destruction Cleanup if necessary.
1243 if (!CleanupDominator && needsEHCleanup(DtorKind)) {
1244 pushRegularPartialArrayCleanup(BeginPtr.getPointer(), CurPtr.getPointer(),
1245 ElementType, ElementAlign,
1246 getDestroyer(DtorKind));
1247 Cleanup = EHStack.stable_begin();
1248 CleanupDominator = Builder.CreateUnreachable();
1251 // Emit the initializer into this element.
1252 StoreAnyExprIntoOneUnit(*this, Init, Init->getType(), CurPtr,
1253 AggValueSlot::DoesNotOverlap);
1255 // Leave the Cleanup if we entered one.
1256 if (CleanupDominator) {
1257 DeactivateCleanupBlock(Cleanup, CleanupDominator);
1258 CleanupDominator->eraseFromParent();
1261 // Advance to the next element by adjusting the pointer type as necessary.
1262 llvm::Value *NextPtr =
1263 Builder.CreateConstInBoundsGEP1_32(ElementTy, CurPtr.getPointer(), 1,
1266 // Check whether we've gotten to the end of the array and, if so,
1268 llvm::Value *IsEnd = Builder.CreateICmpEQ(NextPtr, EndPtr, "array.atend");
1269 Builder.CreateCondBr(IsEnd, ContBB, LoopBB);
1270 CurPtrPhi->addIncoming(NextPtr, Builder.GetInsertBlock());
1275 static void EmitNewInitializer(CodeGenFunction &CGF, const CXXNewExpr *E,
1276 QualType ElementType, llvm::Type *ElementTy,
1277 Address NewPtr, llvm::Value *NumElements,
1278 llvm::Value *AllocSizeWithoutCookie) {
1279 ApplyDebugLocation DL(CGF, E);
1281 CGF.EmitNewArrayInitializer(E, ElementType, ElementTy, NewPtr, NumElements,
1282 AllocSizeWithoutCookie);
1283 else if (const Expr *Init = E->getInitializer())
1284 StoreAnyExprIntoOneUnit(CGF, Init, E->getAllocatedType(), NewPtr,
1285 AggValueSlot::DoesNotOverlap);
1288 /// Emit a call to an operator new or operator delete function, as implicitly
1289 /// created by new-expressions and delete-expressions.
1290 static RValue EmitNewDeleteCall(CodeGenFunction &CGF,
1291 const FunctionDecl *CalleeDecl,
1292 const FunctionProtoType *CalleeType,
1293 const CallArgList &Args) {
1294 llvm::Instruction *CallOrInvoke;
1295 llvm::Constant *CalleePtr = CGF.CGM.GetAddrOfFunction(CalleeDecl);
1296 CGCallee Callee = CGCallee::forDirect(CalleePtr, CalleeDecl);
1298 CGF.EmitCall(CGF.CGM.getTypes().arrangeFreeFunctionCall(
1299 Args, CalleeType, /*chainCall=*/false),
1300 Callee, ReturnValueSlot(), Args, &CallOrInvoke);
1302 /// C++1y [expr.new]p10:
1303 /// [In a new-expression,] an implementation is allowed to omit a call
1304 /// to a replaceable global allocation function.
1306 /// We model such elidable calls with the 'builtin' attribute.
1307 llvm::Function *Fn = dyn_cast<llvm::Function>(CalleePtr);
1308 if (CalleeDecl->isReplaceableGlobalAllocationFunction() &&
1309 Fn && Fn->hasFnAttribute(llvm::Attribute::NoBuiltin)) {
1310 // FIXME: Add addAttribute to CallSite.
1311 if (llvm::CallInst *CI = dyn_cast<llvm::CallInst>(CallOrInvoke))
1312 CI->addAttribute(llvm::AttributeList::FunctionIndex,
1313 llvm::Attribute::Builtin);
1314 else if (llvm::InvokeInst *II = dyn_cast<llvm::InvokeInst>(CallOrInvoke))
1315 II->addAttribute(llvm::AttributeList::FunctionIndex,
1316 llvm::Attribute::Builtin);
1318 llvm_unreachable("unexpected kind of call instruction");
1324 RValue CodeGenFunction::EmitBuiltinNewDeleteCall(const FunctionProtoType *Type,
1325 const CallExpr *TheCall,
1328 EmitCallArgs(Args, Type->getParamTypes(), TheCall->arguments());
1329 // Find the allocation or deallocation function that we're calling.
1330 ASTContext &Ctx = getContext();
1331 DeclarationName Name = Ctx.DeclarationNames
1332 .getCXXOperatorName(IsDelete ? OO_Delete : OO_New);
1334 for (auto *Decl : Ctx.getTranslationUnitDecl()->lookup(Name))
1335 if (auto *FD = dyn_cast<FunctionDecl>(Decl))
1336 if (Ctx.hasSameType(FD->getType(), QualType(Type, 0)))
1337 return EmitNewDeleteCall(*this, FD, Type, Args);
1338 llvm_unreachable("predeclared global operator new/delete is missing");
1342 /// The parameters to pass to a usual operator delete.
1343 struct UsualDeleteParams {
1344 bool DestroyingDelete = false;
1346 bool Alignment = false;
1350 static UsualDeleteParams getUsualDeleteParams(const FunctionDecl *FD) {
1351 UsualDeleteParams Params;
1353 const FunctionProtoType *FPT = FD->getType()->castAs<FunctionProtoType>();
1354 auto AI = FPT->param_type_begin(), AE = FPT->param_type_end();
1356 // The first argument is always a void*.
1359 // The next parameter may be a std::destroying_delete_t.
1360 if (FD->isDestroyingOperatorDelete()) {
1361 Params.DestroyingDelete = true;
1366 // Figure out what other parameters we should be implicitly passing.
1367 if (AI != AE && (*AI)->isIntegerType()) {
1372 if (AI != AE && (*AI)->isAlignValT()) {
1373 Params.Alignment = true;
1377 assert(AI == AE && "unexpected usual deallocation function parameter");
1382 /// A cleanup to call the given 'operator delete' function upon abnormal
1383 /// exit from a new expression. Templated on a traits type that deals with
1384 /// ensuring that the arguments dominate the cleanup if necessary.
1385 template<typename Traits>
1386 class CallDeleteDuringNew final : public EHScopeStack::Cleanup {
1387 /// Type used to hold llvm::Value*s.
1388 typedef typename Traits::ValueTy ValueTy;
1389 /// Type used to hold RValues.
1390 typedef typename Traits::RValueTy RValueTy;
1391 struct PlacementArg {
1396 unsigned NumPlacementArgs : 31;
1397 unsigned PassAlignmentToPlacementDelete : 1;
1398 const FunctionDecl *OperatorDelete;
1401 CharUnits AllocAlign;
1403 PlacementArg *getPlacementArgs() {
1404 return reinterpret_cast<PlacementArg *>(this + 1);
1408 static size_t getExtraSize(size_t NumPlacementArgs) {
1409 return NumPlacementArgs * sizeof(PlacementArg);
1412 CallDeleteDuringNew(size_t NumPlacementArgs,
1413 const FunctionDecl *OperatorDelete, ValueTy Ptr,
1414 ValueTy AllocSize, bool PassAlignmentToPlacementDelete,
1415 CharUnits AllocAlign)
1416 : NumPlacementArgs(NumPlacementArgs),
1417 PassAlignmentToPlacementDelete(PassAlignmentToPlacementDelete),
1418 OperatorDelete(OperatorDelete), Ptr(Ptr), AllocSize(AllocSize),
1419 AllocAlign(AllocAlign) {}
1421 void setPlacementArg(unsigned I, RValueTy Arg, QualType Type) {
1422 assert(I < NumPlacementArgs && "index out of range");
1423 getPlacementArgs()[I] = {Arg, Type};
1426 void Emit(CodeGenFunction &CGF, Flags flags) override {
1427 const FunctionProtoType *FPT =
1428 OperatorDelete->getType()->getAs<FunctionProtoType>();
1429 CallArgList DeleteArgs;
1431 // The first argument is always a void* (or C* for a destroying operator
1432 // delete for class type C).
1433 DeleteArgs.add(Traits::get(CGF, Ptr), FPT->getParamType(0));
1435 // Figure out what other parameters we should be implicitly passing.
1436 UsualDeleteParams Params;
1437 if (NumPlacementArgs) {
1438 // A placement deallocation function is implicitly passed an alignment
1439 // if the placement allocation function was, but is never passed a size.
1440 Params.Alignment = PassAlignmentToPlacementDelete;
1442 // For a non-placement new-expression, 'operator delete' can take a
1443 // size and/or an alignment if it has the right parameters.
1444 Params = getUsualDeleteParams(OperatorDelete);
1447 assert(!Params.DestroyingDelete &&
1448 "should not call destroying delete in a new-expression");
1450 // The second argument can be a std::size_t (for non-placement delete).
1452 DeleteArgs.add(Traits::get(CGF, AllocSize),
1453 CGF.getContext().getSizeType());
1455 // The next (second or third) argument can be a std::align_val_t, which
1456 // is an enum whose underlying type is std::size_t.
1457 // FIXME: Use the right type as the parameter type. Note that in a call
1458 // to operator delete(size_t, ...), we may not have it available.
1459 if (Params.Alignment)
1460 DeleteArgs.add(RValue::get(llvm::ConstantInt::get(
1461 CGF.SizeTy, AllocAlign.getQuantity())),
1462 CGF.getContext().getSizeType());
1464 // Pass the rest of the arguments, which must match exactly.
1465 for (unsigned I = 0; I != NumPlacementArgs; ++I) {
1466 auto Arg = getPlacementArgs()[I];
1467 DeleteArgs.add(Traits::get(CGF, Arg.ArgValue), Arg.ArgType);
1470 // Call 'operator delete'.
1471 EmitNewDeleteCall(CGF, OperatorDelete, FPT, DeleteArgs);
1476 /// Enter a cleanup to call 'operator delete' if the initializer in a
1477 /// new-expression throws.
1478 static void EnterNewDeleteCleanup(CodeGenFunction &CGF,
1479 const CXXNewExpr *E,
1481 llvm::Value *AllocSize,
1482 CharUnits AllocAlign,
1483 const CallArgList &NewArgs) {
1484 unsigned NumNonPlacementArgs = E->passAlignment() ? 2 : 1;
1486 // If we're not inside a conditional branch, then the cleanup will
1487 // dominate and we can do the easier (and more efficient) thing.
1488 if (!CGF.isInConditionalBranch()) {
1489 struct DirectCleanupTraits {
1490 typedef llvm::Value *ValueTy;
1491 typedef RValue RValueTy;
1492 static RValue get(CodeGenFunction &, ValueTy V) { return RValue::get(V); }
1493 static RValue get(CodeGenFunction &, RValueTy V) { return V; }
1496 typedef CallDeleteDuringNew<DirectCleanupTraits> DirectCleanup;
1498 DirectCleanup *Cleanup = CGF.EHStack
1499 .pushCleanupWithExtra<DirectCleanup>(EHCleanup,
1500 E->getNumPlacementArgs(),
1501 E->getOperatorDelete(),
1502 NewPtr.getPointer(),
1506 for (unsigned I = 0, N = E->getNumPlacementArgs(); I != N; ++I) {
1507 auto &Arg = NewArgs[I + NumNonPlacementArgs];
1508 Cleanup->setPlacementArg(I, Arg.getRValue(CGF), Arg.Ty);
1514 // Otherwise, we need to save all this stuff.
1515 DominatingValue<RValue>::saved_type SavedNewPtr =
1516 DominatingValue<RValue>::save(CGF, RValue::get(NewPtr.getPointer()));
1517 DominatingValue<RValue>::saved_type SavedAllocSize =
1518 DominatingValue<RValue>::save(CGF, RValue::get(AllocSize));
1520 struct ConditionalCleanupTraits {
1521 typedef DominatingValue<RValue>::saved_type ValueTy;
1522 typedef DominatingValue<RValue>::saved_type RValueTy;
1523 static RValue get(CodeGenFunction &CGF, ValueTy V) {
1524 return V.restore(CGF);
1527 typedef CallDeleteDuringNew<ConditionalCleanupTraits> ConditionalCleanup;
1529 ConditionalCleanup *Cleanup = CGF.EHStack
1530 .pushCleanupWithExtra<ConditionalCleanup>(EHCleanup,
1531 E->getNumPlacementArgs(),
1532 E->getOperatorDelete(),
1537 for (unsigned I = 0, N = E->getNumPlacementArgs(); I != N; ++I) {
1538 auto &Arg = NewArgs[I + NumNonPlacementArgs];
1539 Cleanup->setPlacementArg(
1540 I, DominatingValue<RValue>::save(CGF, Arg.getRValue(CGF)), Arg.Ty);
1543 CGF.initFullExprCleanup();
1546 llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
1547 // The element type being allocated.
1548 QualType allocType = getContext().getBaseElementType(E->getAllocatedType());
1550 // 1. Build a call to the allocation function.
1551 FunctionDecl *allocator = E->getOperatorNew();
1553 // If there is a brace-initializer, cannot allocate fewer elements than inits.
1554 unsigned minElements = 0;
1555 if (E->isArray() && E->hasInitializer()) {
1556 const InitListExpr *ILE = dyn_cast<InitListExpr>(E->getInitializer());
1557 if (ILE && ILE->isStringLiteralInit())
1559 cast<ConstantArrayType>(ILE->getType()->getAsArrayTypeUnsafe())
1560 ->getSize().getZExtValue();
1562 minElements = ILE->getNumInits();
1565 llvm::Value *numElements = nullptr;
1566 llvm::Value *allocSizeWithoutCookie = nullptr;
1567 llvm::Value *allocSize =
1568 EmitCXXNewAllocSize(*this, E, minElements, numElements,
1569 allocSizeWithoutCookie);
1570 CharUnits allocAlign = getContext().getTypeAlignInChars(allocType);
1572 // Emit the allocation call. If the allocator is a global placement
1573 // operator, just "inline" it directly.
1574 Address allocation = Address::invalid();
1575 CallArgList allocatorArgs;
1576 if (allocator->isReservedGlobalPlacementOperator()) {
1577 assert(E->getNumPlacementArgs() == 1);
1578 const Expr *arg = *E->placement_arguments().begin();
1580 LValueBaseInfo BaseInfo;
1581 allocation = EmitPointerWithAlignment(arg, &BaseInfo);
1583 // The pointer expression will, in many cases, be an opaque void*.
1584 // In these cases, discard the computed alignment and use the
1585 // formal alignment of the allocated type.
1586 if (BaseInfo.getAlignmentSource() != AlignmentSource::Decl)
1587 allocation = Address(allocation.getPointer(), allocAlign);
1589 // Set up allocatorArgs for the call to operator delete if it's not
1590 // the reserved global operator.
1591 if (E->getOperatorDelete() &&
1592 !E->getOperatorDelete()->isReservedGlobalPlacementOperator()) {
1593 allocatorArgs.add(RValue::get(allocSize), getContext().getSizeType());
1594 allocatorArgs.add(RValue::get(allocation.getPointer()), arg->getType());
1598 const FunctionProtoType *allocatorType =
1599 allocator->getType()->castAs<FunctionProtoType>();
1600 unsigned ParamsToSkip = 0;
1602 // The allocation size is the first argument.
1603 QualType sizeType = getContext().getSizeType();
1604 allocatorArgs.add(RValue::get(allocSize), sizeType);
1607 if (allocSize != allocSizeWithoutCookie) {
1608 CharUnits cookieAlign = getSizeAlign(); // FIXME: Ask the ABI.
1609 allocAlign = std::max(allocAlign, cookieAlign);
1612 // The allocation alignment may be passed as the second argument.
1613 if (E->passAlignment()) {
1614 QualType AlignValT = sizeType;
1615 if (allocatorType->getNumParams() > 1) {
1616 AlignValT = allocatorType->getParamType(1);
1617 assert(getContext().hasSameUnqualifiedType(
1618 AlignValT->castAs<EnumType>()->getDecl()->getIntegerType(),
1620 "wrong type for alignment parameter");
1623 // Corner case, passing alignment to 'operator new(size_t, ...)'.
1624 assert(allocator->isVariadic() && "can't pass alignment to allocator");
1627 RValue::get(llvm::ConstantInt::get(SizeTy, allocAlign.getQuantity())),
1631 // FIXME: Why do we not pass a CalleeDecl here?
1632 EmitCallArgs(allocatorArgs, allocatorType, E->placement_arguments(),
1633 /*AC*/AbstractCallee(), /*ParamsToSkip*/ParamsToSkip);
1636 EmitNewDeleteCall(*this, allocator, allocatorType, allocatorArgs);
1638 // If this was a call to a global replaceable allocation function that does
1639 // not take an alignment argument, the allocator is known to produce
1640 // storage that's suitably aligned for any object that fits, up to a known
1641 // threshold. Otherwise assume it's suitably aligned for the allocated type.
1642 CharUnits allocationAlign = allocAlign;
1643 if (!E->passAlignment() &&
1644 allocator->isReplaceableGlobalAllocationFunction()) {
1645 unsigned AllocatorAlign = llvm::PowerOf2Floor(std::min<uint64_t>(
1646 Target.getNewAlign(), getContext().getTypeSize(allocType)));
1647 allocationAlign = std::max(
1648 allocationAlign, getContext().toCharUnitsFromBits(AllocatorAlign));
1651 allocation = Address(RV.getScalarVal(), allocationAlign);
1654 // Emit a null check on the allocation result if the allocation
1655 // function is allowed to return null (because it has a non-throwing
1656 // exception spec or is the reserved placement new) and we have an
1657 // interesting initializer.
1658 bool nullCheck = E->shouldNullCheckAllocation(getContext()) &&
1659 (!allocType.isPODType(getContext()) || E->hasInitializer());
1661 llvm::BasicBlock *nullCheckBB = nullptr;
1662 llvm::BasicBlock *contBB = nullptr;
1664 // The null-check means that the initializer is conditionally
1666 ConditionalEvaluation conditional(*this);
1669 conditional.begin(*this);
1671 nullCheckBB = Builder.GetInsertBlock();
1672 llvm::BasicBlock *notNullBB = createBasicBlock("new.notnull");
1673 contBB = createBasicBlock("new.cont");
1675 llvm::Value *isNull =
1676 Builder.CreateIsNull(allocation.getPointer(), "new.isnull");
1677 Builder.CreateCondBr(isNull, contBB, notNullBB);
1678 EmitBlock(notNullBB);
1681 // If there's an operator delete, enter a cleanup to call it if an
1682 // exception is thrown.
1683 EHScopeStack::stable_iterator operatorDeleteCleanup;
1684 llvm::Instruction *cleanupDominator = nullptr;
1685 if (E->getOperatorDelete() &&
1686 !E->getOperatorDelete()->isReservedGlobalPlacementOperator()) {
1687 EnterNewDeleteCleanup(*this, E, allocation, allocSize, allocAlign,
1689 operatorDeleteCleanup = EHStack.stable_begin();
1690 cleanupDominator = Builder.CreateUnreachable();
1693 assert((allocSize == allocSizeWithoutCookie) ==
1694 CalculateCookiePadding(*this, E).isZero());
1695 if (allocSize != allocSizeWithoutCookie) {
1696 assert(E->isArray());
1697 allocation = CGM.getCXXABI().InitializeArrayCookie(*this, allocation,
1702 llvm::Type *elementTy = ConvertTypeForMem(allocType);
1703 Address result = Builder.CreateElementBitCast(allocation, elementTy);
1705 // Passing pointer through launder.invariant.group to avoid propagation of
1706 // vptrs information which may be included in previous type.
1707 // To not break LTO with different optimizations levels, we do it regardless
1708 // of optimization level.
1709 if (CGM.getCodeGenOpts().StrictVTablePointers &&
1710 allocator->isReservedGlobalPlacementOperator())
1711 result = Address(Builder.CreateLaunderInvariantGroup(result.getPointer()),
1712 result.getAlignment());
1714 // Emit sanitizer checks for pointer value now, so that in the case of an
1715 // array it was checked only once and not at each constructor call.
1716 EmitTypeCheck(CodeGenFunction::TCK_ConstructorCall,
1717 E->getAllocatedTypeSourceInfo()->getTypeLoc().getBeginLoc(),
1718 result.getPointer(), allocType);
1720 EmitNewInitializer(*this, E, allocType, elementTy, result, numElements,
1721 allocSizeWithoutCookie);
1723 // NewPtr is a pointer to the base element type. If we're
1724 // allocating an array of arrays, we'll need to cast back to the
1725 // array pointer type.
1726 llvm::Type *resultType = ConvertTypeForMem(E->getType());
1727 if (result.getType() != resultType)
1728 result = Builder.CreateBitCast(result, resultType);
1731 // Deactivate the 'operator delete' cleanup if we finished
1733 if (operatorDeleteCleanup.isValid()) {
1734 DeactivateCleanupBlock(operatorDeleteCleanup, cleanupDominator);
1735 cleanupDominator->eraseFromParent();
1738 llvm::Value *resultPtr = result.getPointer();
1740 conditional.end(*this);
1742 llvm::BasicBlock *notNullBB = Builder.GetInsertBlock();
1745 llvm::PHINode *PHI = Builder.CreatePHI(resultPtr->getType(), 2);
1746 PHI->addIncoming(resultPtr, notNullBB);
1747 PHI->addIncoming(llvm::Constant::getNullValue(resultPtr->getType()),
1756 void CodeGenFunction::EmitDeleteCall(const FunctionDecl *DeleteFD,
1757 llvm::Value *Ptr, QualType DeleteTy,
1758 llvm::Value *NumElements,
1759 CharUnits CookieSize) {
1760 assert((!NumElements && CookieSize.isZero()) ||
1761 DeleteFD->getOverloadedOperator() == OO_Array_Delete);
1763 const FunctionProtoType *DeleteFTy =
1764 DeleteFD->getType()->getAs<FunctionProtoType>();
1766 CallArgList DeleteArgs;
1768 auto Params = getUsualDeleteParams(DeleteFD);
1769 auto ParamTypeIt = DeleteFTy->param_type_begin();
1771 // Pass the pointer itself.
1772 QualType ArgTy = *ParamTypeIt++;
1773 llvm::Value *DeletePtr = Builder.CreateBitCast(Ptr, ConvertType(ArgTy));
1774 DeleteArgs.add(RValue::get(DeletePtr), ArgTy);
1776 // Pass the std::destroying_delete tag if present.
1777 if (Params.DestroyingDelete) {
1778 QualType DDTag = *ParamTypeIt++;
1779 // Just pass an 'undef'. We expect the tag type to be an empty struct.
1780 auto *V = llvm::UndefValue::get(getTypes().ConvertType(DDTag));
1781 DeleteArgs.add(RValue::get(V), DDTag);
1784 // Pass the size if the delete function has a size_t parameter.
1786 QualType SizeType = *ParamTypeIt++;
1787 CharUnits DeleteTypeSize = getContext().getTypeSizeInChars(DeleteTy);
1788 llvm::Value *Size = llvm::ConstantInt::get(ConvertType(SizeType),
1789 DeleteTypeSize.getQuantity());
1791 // For array new, multiply by the number of elements.
1793 Size = Builder.CreateMul(Size, NumElements);
1795 // If there is a cookie, add the cookie size.
1796 if (!CookieSize.isZero())
1797 Size = Builder.CreateAdd(
1798 Size, llvm::ConstantInt::get(SizeTy, CookieSize.getQuantity()));
1800 DeleteArgs.add(RValue::get(Size), SizeType);
1803 // Pass the alignment if the delete function has an align_val_t parameter.
1804 if (Params.Alignment) {
1805 QualType AlignValType = *ParamTypeIt++;
1806 CharUnits DeleteTypeAlign = getContext().toCharUnitsFromBits(
1807 getContext().getTypeAlignIfKnown(DeleteTy));
1808 llvm::Value *Align = llvm::ConstantInt::get(ConvertType(AlignValType),
1809 DeleteTypeAlign.getQuantity());
1810 DeleteArgs.add(RValue::get(Align), AlignValType);
1813 assert(ParamTypeIt == DeleteFTy->param_type_end() &&
1814 "unknown parameter to usual delete function");
1816 // Emit the call to delete.
1817 EmitNewDeleteCall(*this, DeleteFD, DeleteFTy, DeleteArgs);
1821 /// Calls the given 'operator delete' on a single object.
1822 struct CallObjectDelete final : EHScopeStack::Cleanup {
1824 const FunctionDecl *OperatorDelete;
1825 QualType ElementType;
1827 CallObjectDelete(llvm::Value *Ptr,
1828 const FunctionDecl *OperatorDelete,
1829 QualType ElementType)
1830 : Ptr(Ptr), OperatorDelete(OperatorDelete), ElementType(ElementType) {}
1832 void Emit(CodeGenFunction &CGF, Flags flags) override {
1833 CGF.EmitDeleteCall(OperatorDelete, Ptr, ElementType);
1839 CodeGenFunction::pushCallObjectDeleteCleanup(const FunctionDecl *OperatorDelete,
1840 llvm::Value *CompletePtr,
1841 QualType ElementType) {
1842 EHStack.pushCleanup<CallObjectDelete>(NormalAndEHCleanup, CompletePtr,
1843 OperatorDelete, ElementType);
1846 /// Emit the code for deleting a single object with a destroying operator
1847 /// delete. If the element type has a non-virtual destructor, Ptr has already
1848 /// been converted to the type of the parameter of 'operator delete'. Otherwise
1849 /// Ptr points to an object of the static type.
1850 static void EmitDestroyingObjectDelete(CodeGenFunction &CGF,
1851 const CXXDeleteExpr *DE, Address Ptr,
1852 QualType ElementType) {
1853 auto *Dtor = ElementType->getAsCXXRecordDecl()->getDestructor();
1854 if (Dtor && Dtor->isVirtual())
1855 CGF.CGM.getCXXABI().emitVirtualObjectDelete(CGF, DE, Ptr, ElementType,
1858 CGF.EmitDeleteCall(DE->getOperatorDelete(), Ptr.getPointer(), ElementType);
1861 /// Emit the code for deleting a single object.
1862 static void EmitObjectDelete(CodeGenFunction &CGF,
1863 const CXXDeleteExpr *DE,
1865 QualType ElementType) {
1866 // C++11 [expr.delete]p3:
1867 // If the static type of the object to be deleted is different from its
1868 // dynamic type, the static type shall be a base class of the dynamic type
1869 // of the object to be deleted and the static type shall have a virtual
1870 // destructor or the behavior is undefined.
1871 CGF.EmitTypeCheck(CodeGenFunction::TCK_MemberCall,
1872 DE->getExprLoc(), Ptr.getPointer(),
1875 const FunctionDecl *OperatorDelete = DE->getOperatorDelete();
1876 assert(!OperatorDelete->isDestroyingOperatorDelete());
1878 // Find the destructor for the type, if applicable. If the
1879 // destructor is virtual, we'll just emit the vcall and return.
1880 const CXXDestructorDecl *Dtor = nullptr;
1881 if (const RecordType *RT = ElementType->getAs<RecordType>()) {
1882 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
1883 if (RD->hasDefinition() && !RD->hasTrivialDestructor()) {
1884 Dtor = RD->getDestructor();
1886 if (Dtor->isVirtual()) {
1887 CGF.CGM.getCXXABI().emitVirtualObjectDelete(CGF, DE, Ptr, ElementType,
1894 // Make sure that we call delete even if the dtor throws.
1895 // This doesn't have to a conditional cleanup because we're going
1896 // to pop it off in a second.
1897 CGF.EHStack.pushCleanup<CallObjectDelete>(NormalAndEHCleanup,
1899 OperatorDelete, ElementType);
1902 CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
1903 /*ForVirtualBase=*/false,
1904 /*Delegating=*/false,
1906 else if (auto Lifetime = ElementType.getObjCLifetime()) {
1908 case Qualifiers::OCL_None:
1909 case Qualifiers::OCL_ExplicitNone:
1910 case Qualifiers::OCL_Autoreleasing:
1913 case Qualifiers::OCL_Strong:
1914 CGF.EmitARCDestroyStrong(Ptr, ARCPreciseLifetime);
1917 case Qualifiers::OCL_Weak:
1918 CGF.EmitARCDestroyWeak(Ptr);
1923 CGF.PopCleanupBlock();
1927 /// Calls the given 'operator delete' on an array of objects.
1928 struct CallArrayDelete final : EHScopeStack::Cleanup {
1930 const FunctionDecl *OperatorDelete;
1931 llvm::Value *NumElements;
1932 QualType ElementType;
1933 CharUnits CookieSize;
1935 CallArrayDelete(llvm::Value *Ptr,
1936 const FunctionDecl *OperatorDelete,
1937 llvm::Value *NumElements,
1938 QualType ElementType,
1939 CharUnits CookieSize)
1940 : Ptr(Ptr), OperatorDelete(OperatorDelete), NumElements(NumElements),
1941 ElementType(ElementType), CookieSize(CookieSize) {}
1943 void Emit(CodeGenFunction &CGF, Flags flags) override {
1944 CGF.EmitDeleteCall(OperatorDelete, Ptr, ElementType, NumElements,
1950 /// Emit the code for deleting an array of objects.
1951 static void EmitArrayDelete(CodeGenFunction &CGF,
1952 const CXXDeleteExpr *E,
1954 QualType elementType) {
1955 llvm::Value *numElements = nullptr;
1956 llvm::Value *allocatedPtr = nullptr;
1957 CharUnits cookieSize;
1958 CGF.CGM.getCXXABI().ReadArrayCookie(CGF, deletedPtr, E, elementType,
1959 numElements, allocatedPtr, cookieSize);
1961 assert(allocatedPtr && "ReadArrayCookie didn't set allocated pointer");
1963 // Make sure that we call delete even if one of the dtors throws.
1964 const FunctionDecl *operatorDelete = E->getOperatorDelete();
1965 CGF.EHStack.pushCleanup<CallArrayDelete>(NormalAndEHCleanup,
1966 allocatedPtr, operatorDelete,
1967 numElements, elementType,
1970 // Destroy the elements.
1971 if (QualType::DestructionKind dtorKind = elementType.isDestructedType()) {
1972 assert(numElements && "no element count for a type with a destructor!");
1974 CharUnits elementSize = CGF.getContext().getTypeSizeInChars(elementType);
1975 CharUnits elementAlign =
1976 deletedPtr.getAlignment().alignmentOfArrayElement(elementSize);
1978 llvm::Value *arrayBegin = deletedPtr.getPointer();
1979 llvm::Value *arrayEnd =
1980 CGF.Builder.CreateInBoundsGEP(arrayBegin, numElements, "delete.end");
1982 // Note that it is legal to allocate a zero-length array, and we
1983 // can never fold the check away because the length should always
1984 // come from a cookie.
1985 CGF.emitArrayDestroy(arrayBegin, arrayEnd, elementType, elementAlign,
1986 CGF.getDestroyer(dtorKind),
1987 /*checkZeroLength*/ true,
1988 CGF.needsEHCleanup(dtorKind));
1991 // Pop the cleanup block.
1992 CGF.PopCleanupBlock();
1995 void CodeGenFunction::EmitCXXDeleteExpr(const CXXDeleteExpr *E) {
1996 const Expr *Arg = E->getArgument();
1997 Address Ptr = EmitPointerWithAlignment(Arg);
1999 // Null check the pointer.
2000 llvm::BasicBlock *DeleteNotNull = createBasicBlock("delete.notnull");
2001 llvm::BasicBlock *DeleteEnd = createBasicBlock("delete.end");
2003 llvm::Value *IsNull = Builder.CreateIsNull(Ptr.getPointer(), "isnull");
2005 Builder.CreateCondBr(IsNull, DeleteEnd, DeleteNotNull);
2006 EmitBlock(DeleteNotNull);
2008 QualType DeleteTy = E->getDestroyedType();
2010 // A destroying operator delete overrides the entire operation of the
2011 // delete expression.
2012 if (E->getOperatorDelete()->isDestroyingOperatorDelete()) {
2013 EmitDestroyingObjectDelete(*this, E, Ptr, DeleteTy);
2014 EmitBlock(DeleteEnd);
2018 // We might be deleting a pointer to array. If so, GEP down to the
2019 // first non-array element.
2020 // (this assumes that A(*)[3][7] is converted to [3 x [7 x %A]]*)
2021 if (DeleteTy->isConstantArrayType()) {
2022 llvm::Value *Zero = Builder.getInt32(0);
2023 SmallVector<llvm::Value*,8> GEP;
2025 GEP.push_back(Zero); // point at the outermost array
2027 // For each layer of array type we're pointing at:
2028 while (const ConstantArrayType *Arr
2029 = getContext().getAsConstantArrayType(DeleteTy)) {
2030 // 1. Unpeel the array type.
2031 DeleteTy = Arr->getElementType();
2033 // 2. GEP to the first element of the array.
2034 GEP.push_back(Zero);
2037 Ptr = Address(Builder.CreateInBoundsGEP(Ptr.getPointer(), GEP, "del.first"),
2038 Ptr.getAlignment());
2041 assert(ConvertTypeForMem(DeleteTy) == Ptr.getElementType());
2043 if (E->isArrayForm()) {
2044 EmitArrayDelete(*this, E, Ptr, DeleteTy);
2046 EmitObjectDelete(*this, E, Ptr, DeleteTy);
2049 EmitBlock(DeleteEnd);
2052 static bool isGLValueFromPointerDeref(const Expr *E) {
2053 E = E->IgnoreParens();
2055 if (const auto *CE = dyn_cast<CastExpr>(E)) {
2056 if (!CE->getSubExpr()->isGLValue())
2058 return isGLValueFromPointerDeref(CE->getSubExpr());
2061 if (const auto *OVE = dyn_cast<OpaqueValueExpr>(E))
2062 return isGLValueFromPointerDeref(OVE->getSourceExpr());
2064 if (const auto *BO = dyn_cast<BinaryOperator>(E))
2065 if (BO->getOpcode() == BO_Comma)
2066 return isGLValueFromPointerDeref(BO->getRHS());
2068 if (const auto *ACO = dyn_cast<AbstractConditionalOperator>(E))
2069 return isGLValueFromPointerDeref(ACO->getTrueExpr()) ||
2070 isGLValueFromPointerDeref(ACO->getFalseExpr());
2072 // C++11 [expr.sub]p1:
2073 // The expression E1[E2] is identical (by definition) to *((E1)+(E2))
2074 if (isa<ArraySubscriptExpr>(E))
2077 if (const auto *UO = dyn_cast<UnaryOperator>(E))
2078 if (UO->getOpcode() == UO_Deref)
2084 static llvm::Value *EmitTypeidFromVTable(CodeGenFunction &CGF, const Expr *E,
2085 llvm::Type *StdTypeInfoPtrTy) {
2086 // Get the vtable pointer.
2087 Address ThisPtr = CGF.EmitLValue(E).getAddress();
2089 QualType SrcRecordTy = E->getType();
2091 // C++ [class.cdtor]p4:
2092 // If the operand of typeid refers to the object under construction or
2093 // destruction and the static type of the operand is neither the constructor
2094 // or destructor’s class nor one of its bases, the behavior is undefined.
2095 CGF.EmitTypeCheck(CodeGenFunction::TCK_DynamicOperation, E->getExprLoc(),
2096 ThisPtr.getPointer(), SrcRecordTy);
2098 // C++ [expr.typeid]p2:
2099 // If the glvalue expression is obtained by applying the unary * operator to
2100 // a pointer and the pointer is a null pointer value, the typeid expression
2101 // throws the std::bad_typeid exception.
2103 // However, this paragraph's intent is not clear. We choose a very generous
2104 // interpretation which implores us to consider comma operators, conditional
2105 // operators, parentheses and other such constructs.
2106 if (CGF.CGM.getCXXABI().shouldTypeidBeNullChecked(
2107 isGLValueFromPointerDeref(E), SrcRecordTy)) {
2108 llvm::BasicBlock *BadTypeidBlock =
2109 CGF.createBasicBlock("typeid.bad_typeid");
2110 llvm::BasicBlock *EndBlock = CGF.createBasicBlock("typeid.end");
2112 llvm::Value *IsNull = CGF.Builder.CreateIsNull(ThisPtr.getPointer());
2113 CGF.Builder.CreateCondBr(IsNull, BadTypeidBlock, EndBlock);
2115 CGF.EmitBlock(BadTypeidBlock);
2116 CGF.CGM.getCXXABI().EmitBadTypeidCall(CGF);
2117 CGF.EmitBlock(EndBlock);
2120 return CGF.CGM.getCXXABI().EmitTypeid(CGF, SrcRecordTy, ThisPtr,
2124 llvm::Value *CodeGenFunction::EmitCXXTypeidExpr(const CXXTypeidExpr *E) {
2125 llvm::Type *StdTypeInfoPtrTy =
2126 ConvertType(E->getType())->getPointerTo();
2128 if (E->isTypeOperand()) {
2129 llvm::Constant *TypeInfo =
2130 CGM.GetAddrOfRTTIDescriptor(E->getTypeOperand(getContext()));
2131 return Builder.CreateBitCast(TypeInfo, StdTypeInfoPtrTy);
2134 // C++ [expr.typeid]p2:
2135 // When typeid is applied to a glvalue expression whose type is a
2136 // polymorphic class type, the result refers to a std::type_info object
2137 // representing the type of the most derived object (that is, the dynamic
2138 // type) to which the glvalue refers.
2139 if (E->isPotentiallyEvaluated())
2140 return EmitTypeidFromVTable(*this, E->getExprOperand(),
2143 QualType OperandTy = E->getExprOperand()->getType();
2144 return Builder.CreateBitCast(CGM.GetAddrOfRTTIDescriptor(OperandTy),
2148 static llvm::Value *EmitDynamicCastToNull(CodeGenFunction &CGF,
2150 llvm::Type *DestLTy = CGF.ConvertType(DestTy);
2151 if (DestTy->isPointerType())
2152 return llvm::Constant::getNullValue(DestLTy);
2154 /// C++ [expr.dynamic.cast]p9:
2155 /// A failed cast to reference type throws std::bad_cast
2156 if (!CGF.CGM.getCXXABI().EmitBadCastCall(CGF))
2159 CGF.EmitBlock(CGF.createBasicBlock("dynamic_cast.end"));
2160 return llvm::UndefValue::get(DestLTy);
2163 llvm::Value *CodeGenFunction::EmitDynamicCast(Address ThisAddr,
2164 const CXXDynamicCastExpr *DCE) {
2165 CGM.EmitExplicitCastExprType(DCE, this);
2166 QualType DestTy = DCE->getTypeAsWritten();
2168 QualType SrcTy = DCE->getSubExpr()->getType();
2170 // C++ [expr.dynamic.cast]p7:
2171 // If T is "pointer to cv void," then the result is a pointer to the most
2172 // derived object pointed to by v.
2173 const PointerType *DestPTy = DestTy->getAs<PointerType>();
2175 bool isDynamicCastToVoid;
2176 QualType SrcRecordTy;
2177 QualType DestRecordTy;
2179 isDynamicCastToVoid = DestPTy->getPointeeType()->isVoidType();
2180 SrcRecordTy = SrcTy->castAs<PointerType>()->getPointeeType();
2181 DestRecordTy = DestPTy->getPointeeType();
2183 isDynamicCastToVoid = false;
2184 SrcRecordTy = SrcTy;
2185 DestRecordTy = DestTy->castAs<ReferenceType>()->getPointeeType();
2188 // C++ [class.cdtor]p5:
2189 // If the operand of the dynamic_cast refers to the object under
2190 // construction or destruction and the static type of the operand is not a
2191 // pointer to or object of the constructor or destructor’s own class or one
2192 // of its bases, the dynamic_cast results in undefined behavior.
2193 EmitTypeCheck(TCK_DynamicOperation, DCE->getExprLoc(), ThisAddr.getPointer(),
2196 if (DCE->isAlwaysNull())
2197 if (llvm::Value *T = EmitDynamicCastToNull(*this, DestTy))
2200 assert(SrcRecordTy->isRecordType() && "source type must be a record type!");
2202 // C++ [expr.dynamic.cast]p4:
2203 // If the value of v is a null pointer value in the pointer case, the result
2204 // is the null pointer value of type T.
2205 bool ShouldNullCheckSrcValue =
2206 CGM.getCXXABI().shouldDynamicCastCallBeNullChecked(SrcTy->isPointerType(),
2209 llvm::BasicBlock *CastNull = nullptr;
2210 llvm::BasicBlock *CastNotNull = nullptr;
2211 llvm::BasicBlock *CastEnd = createBasicBlock("dynamic_cast.end");
2213 if (ShouldNullCheckSrcValue) {
2214 CastNull = createBasicBlock("dynamic_cast.null");
2215 CastNotNull = createBasicBlock("dynamic_cast.notnull");
2217 llvm::Value *IsNull = Builder.CreateIsNull(ThisAddr.getPointer());
2218 Builder.CreateCondBr(IsNull, CastNull, CastNotNull);
2219 EmitBlock(CastNotNull);
2223 if (isDynamicCastToVoid) {
2224 Value = CGM.getCXXABI().EmitDynamicCastToVoid(*this, ThisAddr, SrcRecordTy,
2227 assert(DestRecordTy->isRecordType() &&
2228 "destination type must be a record type!");
2229 Value = CGM.getCXXABI().EmitDynamicCastCall(*this, ThisAddr, SrcRecordTy,
2230 DestTy, DestRecordTy, CastEnd);
2231 CastNotNull = Builder.GetInsertBlock();
2234 if (ShouldNullCheckSrcValue) {
2235 EmitBranch(CastEnd);
2237 EmitBlock(CastNull);
2238 EmitBranch(CastEnd);
2243 if (ShouldNullCheckSrcValue) {
2244 llvm::PHINode *PHI = Builder.CreatePHI(Value->getType(), 2);
2245 PHI->addIncoming(Value, CastNotNull);
2246 PHI->addIncoming(llvm::Constant::getNullValue(Value->getType()), CastNull);
2254 void CodeGenFunction::EmitLambdaExpr(const LambdaExpr *E, AggValueSlot Slot) {
2255 RunCleanupsScope Scope(*this);
2256 LValue SlotLV = MakeAddrLValue(Slot.getAddress(), E->getType());
2258 CXXRecordDecl::field_iterator CurField = E->getLambdaClass()->field_begin();
2259 for (LambdaExpr::const_capture_init_iterator i = E->capture_init_begin(),
2260 e = E->capture_init_end();
2261 i != e; ++i, ++CurField) {
2262 // Emit initialization
2263 LValue LV = EmitLValueForFieldInitialization(SlotLV, *CurField);
2264 if (CurField->hasCapturedVLAType()) {
2265 auto VAT = CurField->getCapturedVLAType();
2266 EmitStoreThroughLValue(RValue::get(VLASizeMap[VAT->getSizeExpr()]), LV);
2268 EmitInitializerForField(*CurField, LV, *i);