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);
95 RValue CodeGenFunction::EmitCXXDestructorCall(
96 const CXXDestructorDecl *DD, const CGCallee &Callee, llvm::Value *This,
97 llvm::Value *ImplicitParam, QualType ImplicitParamTy, const CallExpr *CE,
100 commonEmitCXXMemberOrOperatorCall(*this, DD, This, ImplicitParam,
101 ImplicitParamTy, CE, Args, nullptr);
102 return EmitCall(CGM.getTypes().arrangeCXXStructorDeclaration(DD, Type),
103 Callee, ReturnValueSlot(), Args);
106 RValue CodeGenFunction::EmitCXXPseudoDestructorExpr(
107 const CXXPseudoDestructorExpr *E) {
108 QualType DestroyedType = E->getDestroyedType();
109 if (DestroyedType.hasStrongOrWeakObjCLifetime()) {
110 // Automatic Reference Counting:
111 // If the pseudo-expression names a retainable object with weak or
112 // strong lifetime, the object shall be released.
113 Expr *BaseExpr = E->getBase();
114 Address BaseValue = Address::invalid();
115 Qualifiers BaseQuals;
117 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
119 BaseValue = EmitPointerWithAlignment(BaseExpr);
120 const PointerType *PTy = BaseExpr->getType()->getAs<PointerType>();
121 BaseQuals = PTy->getPointeeType().getQualifiers();
123 LValue BaseLV = EmitLValue(BaseExpr);
124 BaseValue = BaseLV.getAddress();
125 QualType BaseTy = BaseExpr->getType();
126 BaseQuals = BaseTy.getQualifiers();
129 switch (DestroyedType.getObjCLifetime()) {
130 case Qualifiers::OCL_None:
131 case Qualifiers::OCL_ExplicitNone:
132 case Qualifiers::OCL_Autoreleasing:
135 case Qualifiers::OCL_Strong:
136 EmitARCRelease(Builder.CreateLoad(BaseValue,
137 DestroyedType.isVolatileQualified()),
141 case Qualifiers::OCL_Weak:
142 EmitARCDestroyWeak(BaseValue);
146 // C++ [expr.pseudo]p1:
147 // The result shall only be used as the operand for the function call
148 // operator (), and the result of such a call has type void. The only
149 // effect is the evaluation of the postfix-expression before the dot or
151 EmitIgnoredExpr(E->getBase());
154 return RValue::get(nullptr);
157 static CXXRecordDecl *getCXXRecord(const Expr *E) {
158 QualType T = E->getType();
159 if (const PointerType *PTy = T->getAs<PointerType>())
160 T = PTy->getPointeeType();
161 const RecordType *Ty = T->castAs<RecordType>();
162 return cast<CXXRecordDecl>(Ty->getDecl());
165 // Note: This function also emit constructor calls to support a MSVC
166 // extensions allowing explicit constructor function call.
167 RValue CodeGenFunction::EmitCXXMemberCallExpr(const CXXMemberCallExpr *CE,
168 ReturnValueSlot ReturnValue) {
169 const Expr *callee = CE->getCallee()->IgnoreParens();
171 if (isa<BinaryOperator>(callee))
172 return EmitCXXMemberPointerCallExpr(CE, ReturnValue);
174 const MemberExpr *ME = cast<MemberExpr>(callee);
175 const CXXMethodDecl *MD = cast<CXXMethodDecl>(ME->getMemberDecl());
177 if (MD->isStatic()) {
178 // The method is static, emit it as we would a regular call.
179 CGCallee callee = CGCallee::forDirect(CGM.GetAddrOfFunction(MD), MD);
180 return EmitCall(getContext().getPointerType(MD->getType()), callee, CE,
184 bool HasQualifier = ME->hasQualifier();
185 NestedNameSpecifier *Qualifier = HasQualifier ? ME->getQualifier() : nullptr;
186 bool IsArrow = ME->isArrow();
187 const Expr *Base = ME->getBase();
189 return EmitCXXMemberOrOperatorMemberCallExpr(
190 CE, MD, ReturnValue, HasQualifier, Qualifier, IsArrow, Base);
193 RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
194 const CallExpr *CE, const CXXMethodDecl *MD, ReturnValueSlot ReturnValue,
195 bool HasQualifier, NestedNameSpecifier *Qualifier, bool IsArrow,
197 assert(isa<CXXMemberCallExpr>(CE) || isa<CXXOperatorCallExpr>(CE));
199 // Compute the object pointer.
200 bool CanUseVirtualCall = MD->isVirtual() && !HasQualifier;
202 const CXXMethodDecl *DevirtualizedMethod = nullptr;
203 if (CanUseVirtualCall &&
204 MD->getDevirtualizedMethod(Base, getLangOpts().AppleKext)) {
205 const CXXRecordDecl *BestDynamicDecl = Base->getBestDynamicClassType();
206 DevirtualizedMethod = MD->getCorrespondingMethodInClass(BestDynamicDecl);
207 assert(DevirtualizedMethod);
208 const CXXRecordDecl *DevirtualizedClass = DevirtualizedMethod->getParent();
209 const Expr *Inner = Base->ignoreParenBaseCasts();
210 if (DevirtualizedMethod->getReturnType().getCanonicalType() !=
211 MD->getReturnType().getCanonicalType())
212 // If the return types are not the same, this might be a case where more
213 // code needs to run to compensate for it. For example, the derived
214 // method might return a type that inherits form from the return
215 // type of MD and has a prefix.
216 // For now we just avoid devirtualizing these covariant cases.
217 DevirtualizedMethod = nullptr;
218 else if (getCXXRecord(Inner) == DevirtualizedClass)
219 // If the class of the Inner expression is where the dynamic method
220 // is defined, build the this pointer from it.
222 else if (getCXXRecord(Base) != DevirtualizedClass) {
223 // If the method is defined in a class that is not the best dynamic
224 // one or the one of the full expression, we would have to build
225 // a derived-to-base cast to compute the correct this pointer, but
226 // we don't have support for that yet, so do a virtual call.
227 DevirtualizedMethod = nullptr;
231 // C++17 demands that we evaluate the RHS of a (possibly-compound) assignment
232 // operator before the LHS.
233 CallArgList RtlArgStorage;
234 CallArgList *RtlArgs = nullptr;
235 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(CE)) {
236 if (OCE->isAssignmentOp()) {
237 RtlArgs = &RtlArgStorage;
238 EmitCallArgs(*RtlArgs, MD->getType()->castAs<FunctionProtoType>(),
239 drop_begin(CE->arguments(), 1), CE->getDirectCallee(),
240 /*ParamsToSkip*/0, EvaluationOrder::ForceRightToLeft);
244 Address This = Address::invalid();
246 This = EmitPointerWithAlignment(Base);
248 This = EmitLValue(Base).getAddress();
251 if (MD->isTrivial() || (MD->isDefaulted() && MD->getParent()->isUnion())) {
252 if (isa<CXXDestructorDecl>(MD)) return RValue::get(nullptr);
253 if (isa<CXXConstructorDecl>(MD) &&
254 cast<CXXConstructorDecl>(MD)->isDefaultConstructor())
255 return RValue::get(nullptr);
257 if (!MD->getParent()->mayInsertExtraPadding()) {
258 if (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator()) {
259 // We don't like to generate the trivial copy/move assignment operator
260 // when it isn't necessary; just produce the proper effect here.
261 LValue RHS = isa<CXXOperatorCallExpr>(CE)
262 ? MakeNaturalAlignAddrLValue(
263 (*RtlArgs)[0].RV.getScalarVal(),
264 (*(CE->arg_begin() + 1))->getType())
265 : EmitLValue(*CE->arg_begin());
266 EmitAggregateAssign(This, RHS.getAddress(), CE->getType());
267 return RValue::get(This.getPointer());
270 if (isa<CXXConstructorDecl>(MD) &&
271 cast<CXXConstructorDecl>(MD)->isCopyOrMoveConstructor()) {
272 // Trivial move and copy ctor are the same.
273 assert(CE->getNumArgs() == 1 && "unexpected argcount for trivial ctor");
274 Address RHS = EmitLValue(*CE->arg_begin()).getAddress();
275 EmitAggregateCopy(This, RHS, (*CE->arg_begin())->getType());
276 return RValue::get(This.getPointer());
278 llvm_unreachable("unknown trivial member function");
282 // Compute the function type we're calling.
283 const CXXMethodDecl *CalleeDecl =
284 DevirtualizedMethod ? DevirtualizedMethod : MD;
285 const CGFunctionInfo *FInfo = nullptr;
286 if (const auto *Dtor = dyn_cast<CXXDestructorDecl>(CalleeDecl))
287 FInfo = &CGM.getTypes().arrangeCXXStructorDeclaration(
288 Dtor, StructorType::Complete);
289 else if (const auto *Ctor = dyn_cast<CXXConstructorDecl>(CalleeDecl))
290 FInfo = &CGM.getTypes().arrangeCXXStructorDeclaration(
291 Ctor, StructorType::Complete);
293 FInfo = &CGM.getTypes().arrangeCXXMethodDeclaration(CalleeDecl);
295 llvm::FunctionType *Ty = CGM.getTypes().GetFunctionType(*FInfo);
297 // C++11 [class.mfct.non-static]p2:
298 // If a non-static member function of a class X is called for an object that
299 // is not of type X, or of a type derived from X, the behavior is undefined.
300 SourceLocation CallLoc;
301 ASTContext &C = getContext();
303 CallLoc = CE->getExprLoc();
305 SanitizerSet SkippedChecks;
306 if (const auto *CMCE = dyn_cast<CXXMemberCallExpr>(CE)) {
307 auto *IOA = CMCE->getImplicitObjectArgument();
308 bool IsImplicitObjectCXXThis = IsWrappedCXXThis(IOA);
309 if (IsImplicitObjectCXXThis)
310 SkippedChecks.set(SanitizerKind::Alignment, true);
311 if (IsImplicitObjectCXXThis || isa<DeclRefExpr>(IOA))
312 SkippedChecks.set(SanitizerKind::Null, true);
315 isa<CXXConstructorDecl>(CalleeDecl) ? CodeGenFunction::TCK_ConstructorCall
316 : CodeGenFunction::TCK_MemberCall,
317 CallLoc, This.getPointer(), C.getRecordType(CalleeDecl->getParent()),
318 /*Alignment=*/CharUnits::Zero(), SkippedChecks);
320 // FIXME: Uses of 'MD' past this point need to be audited. We may need to use
321 // 'CalleeDecl' instead.
323 // C++ [class.virtual]p12:
324 // Explicit qualification with the scope operator (5.1) suppresses the
325 // virtual call mechanism.
327 // We also don't emit a virtual call if the base expression has a record type
328 // because then we know what the type is.
329 bool UseVirtualCall = CanUseVirtualCall && !DevirtualizedMethod;
331 if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(MD)) {
332 assert(CE->arg_begin() == CE->arg_end() &&
333 "Destructor shouldn't have explicit parameters");
334 assert(ReturnValue.isNull() && "Destructor shouldn't have return value");
335 if (UseVirtualCall) {
336 CGM.getCXXABI().EmitVirtualDestructorCall(
337 *this, Dtor, Dtor_Complete, This, cast<CXXMemberCallExpr>(CE));
340 if (getLangOpts().AppleKext && MD->isVirtual() && HasQualifier)
341 Callee = BuildAppleKextVirtualCall(MD, Qualifier, Ty);
342 else if (!DevirtualizedMethod)
343 Callee = CGCallee::forDirect(
344 CGM.getAddrOfCXXStructor(Dtor, StructorType::Complete, FInfo, Ty),
347 const CXXDestructorDecl *DDtor =
348 cast<CXXDestructorDecl>(DevirtualizedMethod);
349 Callee = CGCallee::forDirect(
350 CGM.GetAddrOfFunction(GlobalDecl(DDtor, Dtor_Complete), Ty),
353 EmitCXXMemberOrOperatorCall(
354 CalleeDecl, Callee, ReturnValue, This.getPointer(),
355 /*ImplicitParam=*/nullptr, QualType(), CE, nullptr);
357 return RValue::get(nullptr);
361 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) {
362 Callee = CGCallee::forDirect(
363 CGM.GetAddrOfFunction(GlobalDecl(Ctor, Ctor_Complete), Ty),
365 } else if (UseVirtualCall) {
366 Callee = CGM.getCXXABI().getVirtualFunctionPointer(*this, MD, This, Ty,
369 if (SanOpts.has(SanitizerKind::CFINVCall) &&
370 MD->getParent()->isDynamicClass()) {
372 const CXXRecordDecl *RD;
373 std::tie(VTable, RD) =
374 CGM.getCXXABI().LoadVTablePtr(*this, This, MD->getParent());
375 EmitVTablePtrCheckForCall(RD, VTable, CFITCK_NVCall, CE->getLocStart());
378 if (getLangOpts().AppleKext && MD->isVirtual() && HasQualifier)
379 Callee = BuildAppleKextVirtualCall(MD, Qualifier, Ty);
380 else if (!DevirtualizedMethod)
381 Callee = CGCallee::forDirect(CGM.GetAddrOfFunction(MD, Ty), MD);
383 Callee = CGCallee::forDirect(
384 CGM.GetAddrOfFunction(DevirtualizedMethod, Ty),
385 DevirtualizedMethod);
389 if (MD->isVirtual()) {
390 This = CGM.getCXXABI().adjustThisArgumentForVirtualFunctionCall(
391 *this, CalleeDecl, This, UseVirtualCall);
394 return EmitCXXMemberOrOperatorCall(
395 CalleeDecl, Callee, ReturnValue, This.getPointer(),
396 /*ImplicitParam=*/nullptr, QualType(), CE, RtlArgs);
400 CodeGenFunction::EmitCXXMemberPointerCallExpr(const CXXMemberCallExpr *E,
401 ReturnValueSlot ReturnValue) {
402 const BinaryOperator *BO =
403 cast<BinaryOperator>(E->getCallee()->IgnoreParens());
404 const Expr *BaseExpr = BO->getLHS();
405 const Expr *MemFnExpr = BO->getRHS();
407 const MemberPointerType *MPT =
408 MemFnExpr->getType()->castAs<MemberPointerType>();
410 const FunctionProtoType *FPT =
411 MPT->getPointeeType()->castAs<FunctionProtoType>();
412 const CXXRecordDecl *RD =
413 cast<CXXRecordDecl>(MPT->getClass()->getAs<RecordType>()->getDecl());
415 // Emit the 'this' pointer.
416 Address This = Address::invalid();
417 if (BO->getOpcode() == BO_PtrMemI)
418 This = EmitPointerWithAlignment(BaseExpr);
420 This = EmitLValue(BaseExpr).getAddress();
422 EmitTypeCheck(TCK_MemberCall, E->getExprLoc(), This.getPointer(),
423 QualType(MPT->getClass(), 0));
425 // Get the member function pointer.
426 llvm::Value *MemFnPtr = EmitScalarExpr(MemFnExpr);
428 // Ask the ABI to load the callee. Note that This is modified.
429 llvm::Value *ThisPtrForCall = nullptr;
431 CGM.getCXXABI().EmitLoadOfMemberFunctionPointer(*this, BO, This,
432 ThisPtrForCall, MemFnPtr, MPT);
437 getContext().getPointerType(getContext().getTagDeclType(RD));
439 // Push the this ptr.
440 Args.add(RValue::get(ThisPtrForCall), ThisType);
442 RequiredArgs required =
443 RequiredArgs::forPrototypePlus(FPT, 1, /*FD=*/nullptr);
445 // And the rest of the call args
446 EmitCallArgs(Args, FPT, E->arguments());
447 return EmitCall(CGM.getTypes().arrangeCXXMethodCall(Args, FPT, required,
449 Callee, ReturnValue, Args);
453 CodeGenFunction::EmitCXXOperatorMemberCallExpr(const CXXOperatorCallExpr *E,
454 const CXXMethodDecl *MD,
455 ReturnValueSlot ReturnValue) {
456 assert(MD->isInstance() &&
457 "Trying to emit a member call expr on a static method!");
458 return EmitCXXMemberOrOperatorMemberCallExpr(
459 E, MD, ReturnValue, /*HasQualifier=*/false, /*Qualifier=*/nullptr,
460 /*IsArrow=*/false, E->getArg(0));
463 RValue CodeGenFunction::EmitCUDAKernelCallExpr(const CUDAKernelCallExpr *E,
464 ReturnValueSlot ReturnValue) {
465 return CGM.getCUDARuntime().EmitCUDAKernelCallExpr(*this, E, ReturnValue);
468 static void EmitNullBaseClassInitialization(CodeGenFunction &CGF,
470 const CXXRecordDecl *Base) {
474 DestPtr = CGF.Builder.CreateElementBitCast(DestPtr, CGF.Int8Ty);
476 const ASTRecordLayout &Layout = CGF.getContext().getASTRecordLayout(Base);
477 CharUnits NVSize = Layout.getNonVirtualSize();
479 // We cannot simply zero-initialize the entire base sub-object if vbptrs are
480 // present, they are initialized by the most derived class before calling the
482 SmallVector<std::pair<CharUnits, CharUnits>, 1> Stores;
483 Stores.emplace_back(CharUnits::Zero(), NVSize);
485 // Each store is split by the existence of a vbptr.
486 CharUnits VBPtrWidth = CGF.getPointerSize();
487 std::vector<CharUnits> VBPtrOffsets =
488 CGF.CGM.getCXXABI().getVBPtrOffsets(Base);
489 for (CharUnits VBPtrOffset : VBPtrOffsets) {
490 // Stop before we hit any virtual base pointers located in virtual bases.
491 if (VBPtrOffset >= NVSize)
493 std::pair<CharUnits, CharUnits> LastStore = Stores.pop_back_val();
494 CharUnits LastStoreOffset = LastStore.first;
495 CharUnits LastStoreSize = LastStore.second;
497 CharUnits SplitBeforeOffset = LastStoreOffset;
498 CharUnits SplitBeforeSize = VBPtrOffset - SplitBeforeOffset;
499 assert(!SplitBeforeSize.isNegative() && "negative store size!");
500 if (!SplitBeforeSize.isZero())
501 Stores.emplace_back(SplitBeforeOffset, SplitBeforeSize);
503 CharUnits SplitAfterOffset = VBPtrOffset + VBPtrWidth;
504 CharUnits SplitAfterSize = LastStoreSize - SplitAfterOffset;
505 assert(!SplitAfterSize.isNegative() && "negative store size!");
506 if (!SplitAfterSize.isZero())
507 Stores.emplace_back(SplitAfterOffset, SplitAfterSize);
510 // If the type contains a pointer to data member we can't memset it to zero.
511 // Instead, create a null constant and copy it to the destination.
512 // TODO: there are other patterns besides zero that we can usefully memset,
513 // like -1, which happens to be the pattern used by member-pointers.
514 // TODO: isZeroInitializable can be over-conservative in the case where a
515 // virtual base contains a member pointer.
516 llvm::Constant *NullConstantForBase = CGF.CGM.EmitNullConstantForBase(Base);
517 if (!NullConstantForBase->isNullValue()) {
518 llvm::GlobalVariable *NullVariable = new llvm::GlobalVariable(
519 CGF.CGM.getModule(), NullConstantForBase->getType(),
520 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage,
521 NullConstantForBase, Twine());
523 CharUnits Align = std::max(Layout.getNonVirtualAlignment(),
524 DestPtr.getAlignment());
525 NullVariable->setAlignment(Align.getQuantity());
527 Address SrcPtr = Address(CGF.EmitCastToVoidPtr(NullVariable), Align);
529 // Get and call the appropriate llvm.memcpy overload.
530 for (std::pair<CharUnits, CharUnits> Store : Stores) {
531 CharUnits StoreOffset = Store.first;
532 CharUnits StoreSize = Store.second;
533 llvm::Value *StoreSizeVal = CGF.CGM.getSize(StoreSize);
534 CGF.Builder.CreateMemCpy(
535 CGF.Builder.CreateConstInBoundsByteGEP(DestPtr, StoreOffset),
536 CGF.Builder.CreateConstInBoundsByteGEP(SrcPtr, StoreOffset),
540 // Otherwise, just memset the whole thing to zero. This is legal
541 // because in LLVM, all default initializers (other than the ones we just
542 // handled above) are guaranteed to have a bit pattern of all zeros.
544 for (std::pair<CharUnits, CharUnits> Store : Stores) {
545 CharUnits StoreOffset = Store.first;
546 CharUnits StoreSize = Store.second;
547 llvm::Value *StoreSizeVal = CGF.CGM.getSize(StoreSize);
548 CGF.Builder.CreateMemSet(
549 CGF.Builder.CreateConstInBoundsByteGEP(DestPtr, StoreOffset),
550 CGF.Builder.getInt8(0), StoreSizeVal);
556 CodeGenFunction::EmitCXXConstructExpr(const CXXConstructExpr *E,
558 assert(!Dest.isIgnored() && "Must have a destination!");
559 const CXXConstructorDecl *CD = E->getConstructor();
561 // If we require zero initialization before (or instead of) calling the
562 // constructor, as can be the case with a non-user-provided default
563 // constructor, emit the zero initialization now, unless destination is
565 if (E->requiresZeroInitialization() && !Dest.isZeroed()) {
566 switch (E->getConstructionKind()) {
567 case CXXConstructExpr::CK_Delegating:
568 case CXXConstructExpr::CK_Complete:
569 EmitNullInitialization(Dest.getAddress(), E->getType());
571 case CXXConstructExpr::CK_VirtualBase:
572 case CXXConstructExpr::CK_NonVirtualBase:
573 EmitNullBaseClassInitialization(*this, Dest.getAddress(),
579 // If this is a call to a trivial default constructor, do nothing.
580 if (CD->isTrivial() && CD->isDefaultConstructor())
583 // Elide the constructor if we're constructing from a temporary.
584 // The temporary check is required because Sema sets this on NRVO
586 if (getLangOpts().ElideConstructors && E->isElidable()) {
587 assert(getContext().hasSameUnqualifiedType(E->getType(),
588 E->getArg(0)->getType()));
589 if (E->getArg(0)->isTemporaryObject(getContext(), CD->getParent())) {
590 EmitAggExpr(E->getArg(0), Dest);
595 if (const ArrayType *arrayType
596 = getContext().getAsArrayType(E->getType())) {
597 EmitCXXAggrConstructorCall(CD, arrayType, Dest.getAddress(), E);
599 CXXCtorType Type = Ctor_Complete;
600 bool ForVirtualBase = false;
601 bool Delegating = false;
603 switch (E->getConstructionKind()) {
604 case CXXConstructExpr::CK_Delegating:
605 // We should be emitting a constructor; GlobalDecl will assert this
606 Type = CurGD.getCtorType();
610 case CXXConstructExpr::CK_Complete:
611 Type = Ctor_Complete;
614 case CXXConstructExpr::CK_VirtualBase:
615 ForVirtualBase = true;
618 case CXXConstructExpr::CK_NonVirtualBase:
622 // Call the constructor.
623 EmitCXXConstructorCall(CD, Type, ForVirtualBase, Delegating,
624 Dest.getAddress(), E);
628 void CodeGenFunction::EmitSynthesizedCXXCopyCtor(Address Dest, Address Src,
630 if (const ExprWithCleanups *E = dyn_cast<ExprWithCleanups>(Exp))
631 Exp = E->getSubExpr();
632 assert(isa<CXXConstructExpr>(Exp) &&
633 "EmitSynthesizedCXXCopyCtor - unknown copy ctor expr");
634 const CXXConstructExpr* E = cast<CXXConstructExpr>(Exp);
635 const CXXConstructorDecl *CD = E->getConstructor();
636 RunCleanupsScope Scope(*this);
638 // If we require zero initialization before (or instead of) calling the
639 // constructor, as can be the case with a non-user-provided default
640 // constructor, emit the zero initialization now.
641 // FIXME. Do I still need this for a copy ctor synthesis?
642 if (E->requiresZeroInitialization())
643 EmitNullInitialization(Dest, E->getType());
645 assert(!getContext().getAsConstantArrayType(E->getType())
646 && "EmitSynthesizedCXXCopyCtor - Copied-in Array");
647 EmitSynthesizedCXXCopyCtorCall(CD, Dest, Src, E);
650 static CharUnits CalculateCookiePadding(CodeGenFunction &CGF,
651 const CXXNewExpr *E) {
653 return CharUnits::Zero();
655 // No cookie is required if the operator new[] being used is the
656 // reserved placement operator new[].
657 if (E->getOperatorNew()->isReservedGlobalPlacementOperator())
658 return CharUnits::Zero();
660 return CGF.CGM.getCXXABI().GetArrayCookieSize(E);
663 static llvm::Value *EmitCXXNewAllocSize(CodeGenFunction &CGF,
665 unsigned minElements,
666 llvm::Value *&numElements,
667 llvm::Value *&sizeWithoutCookie) {
668 QualType type = e->getAllocatedType();
671 CharUnits typeSize = CGF.getContext().getTypeSizeInChars(type);
673 = llvm::ConstantInt::get(CGF.SizeTy, typeSize.getQuantity());
674 return sizeWithoutCookie;
677 // The width of size_t.
678 unsigned sizeWidth = CGF.SizeTy->getBitWidth();
680 // Figure out the cookie size.
681 llvm::APInt cookieSize(sizeWidth,
682 CalculateCookiePadding(CGF, e).getQuantity());
684 // Emit the array size expression.
685 // We multiply the size of all dimensions for NumElements.
686 // e.g for 'int[2][3]', ElemType is 'int' and NumElements is 6.
688 ConstantEmitter(CGF).tryEmitAbstract(e->getArraySize(), e->getType());
690 numElements = CGF.EmitScalarExpr(e->getArraySize());
691 assert(isa<llvm::IntegerType>(numElements->getType()));
693 // The number of elements can be have an arbitrary integer type;
694 // essentially, we need to multiply it by a constant factor, add a
695 // cookie size, and verify that the result is representable as a
696 // size_t. That's just a gloss, though, and it's wrong in one
697 // important way: if the count is negative, it's an error even if
698 // the cookie size would bring the total size >= 0.
700 = e->getArraySize()->getType()->isSignedIntegerOrEnumerationType();
701 llvm::IntegerType *numElementsType
702 = cast<llvm::IntegerType>(numElements->getType());
703 unsigned numElementsWidth = numElementsType->getBitWidth();
705 // Compute the constant factor.
706 llvm::APInt arraySizeMultiplier(sizeWidth, 1);
707 while (const ConstantArrayType *CAT
708 = CGF.getContext().getAsConstantArrayType(type)) {
709 type = CAT->getElementType();
710 arraySizeMultiplier *= CAT->getSize();
713 CharUnits typeSize = CGF.getContext().getTypeSizeInChars(type);
714 llvm::APInt typeSizeMultiplier(sizeWidth, typeSize.getQuantity());
715 typeSizeMultiplier *= arraySizeMultiplier;
717 // This will be a size_t.
720 // If someone is doing 'new int[42]' there is no need to do a dynamic check.
721 // Don't bloat the -O0 code.
722 if (llvm::ConstantInt *numElementsC =
723 dyn_cast<llvm::ConstantInt>(numElements)) {
724 const llvm::APInt &count = numElementsC->getValue();
726 bool hasAnyOverflow = false;
728 // If 'count' was a negative number, it's an overflow.
729 if (isSigned && count.isNegative())
730 hasAnyOverflow = true;
732 // We want to do all this arithmetic in size_t. If numElements is
733 // wider than that, check whether it's already too big, and if so,
735 else if (numElementsWidth > sizeWidth &&
736 numElementsWidth - sizeWidth > count.countLeadingZeros())
737 hasAnyOverflow = true;
739 // Okay, compute a count at the right width.
740 llvm::APInt adjustedCount = count.zextOrTrunc(sizeWidth);
742 // If there is a brace-initializer, we cannot allocate fewer elements than
743 // there are initializers. If we do, that's treated like an overflow.
744 if (adjustedCount.ult(minElements))
745 hasAnyOverflow = true;
747 // Scale numElements by that. This might overflow, but we don't
748 // care because it only overflows if allocationSize does, too, and
749 // if that overflows then we shouldn't use this.
750 numElements = llvm::ConstantInt::get(CGF.SizeTy,
751 adjustedCount * arraySizeMultiplier);
753 // Compute the size before cookie, and track whether it overflowed.
755 llvm::APInt allocationSize
756 = adjustedCount.umul_ov(typeSizeMultiplier, overflow);
757 hasAnyOverflow |= overflow;
759 // Add in the cookie, and check whether it's overflowed.
760 if (cookieSize != 0) {
761 // Save the current size without a cookie. This shouldn't be
762 // used if there was overflow.
763 sizeWithoutCookie = llvm::ConstantInt::get(CGF.SizeTy, allocationSize);
765 allocationSize = allocationSize.uadd_ov(cookieSize, overflow);
766 hasAnyOverflow |= overflow;
769 // On overflow, produce a -1 so operator new will fail.
770 if (hasAnyOverflow) {
771 size = llvm::Constant::getAllOnesValue(CGF.SizeTy);
773 size = llvm::ConstantInt::get(CGF.SizeTy, allocationSize);
776 // Otherwise, we might need to use the overflow intrinsics.
778 // There are up to five conditions we need to test for:
779 // 1) if isSigned, we need to check whether numElements is negative;
780 // 2) if numElementsWidth > sizeWidth, we need to check whether
781 // numElements is larger than something representable in size_t;
782 // 3) if minElements > 0, we need to check whether numElements is smaller
784 // 4) we need to compute
785 // sizeWithoutCookie := numElements * typeSizeMultiplier
786 // and check whether it overflows; and
787 // 5) if we need a cookie, we need to compute
788 // size := sizeWithoutCookie + cookieSize
789 // and check whether it overflows.
791 llvm::Value *hasOverflow = nullptr;
793 // If numElementsWidth > sizeWidth, then one way or another, we're
794 // going to have to do a comparison for (2), and this happens to
795 // take care of (1), too.
796 if (numElementsWidth > sizeWidth) {
797 llvm::APInt threshold(numElementsWidth, 1);
798 threshold <<= sizeWidth;
800 llvm::Value *thresholdV
801 = llvm::ConstantInt::get(numElementsType, threshold);
803 hasOverflow = CGF.Builder.CreateICmpUGE(numElements, thresholdV);
804 numElements = CGF.Builder.CreateTrunc(numElements, CGF.SizeTy);
806 // Otherwise, if we're signed, we want to sext up to size_t.
807 } else if (isSigned) {
808 if (numElementsWidth < sizeWidth)
809 numElements = CGF.Builder.CreateSExt(numElements, CGF.SizeTy);
811 // If there's a non-1 type size multiplier, then we can do the
812 // signedness check at the same time as we do the multiply
813 // because a negative number times anything will cause an
814 // unsigned overflow. Otherwise, we have to do it here. But at least
815 // in this case, we can subsume the >= minElements check.
816 if (typeSizeMultiplier == 1)
817 hasOverflow = CGF.Builder.CreateICmpSLT(numElements,
818 llvm::ConstantInt::get(CGF.SizeTy, minElements));
820 // Otherwise, zext up to size_t if necessary.
821 } else if (numElementsWidth < sizeWidth) {
822 numElements = CGF.Builder.CreateZExt(numElements, CGF.SizeTy);
825 assert(numElements->getType() == CGF.SizeTy);
828 // Don't allow allocation of fewer elements than we have initializers.
830 hasOverflow = CGF.Builder.CreateICmpULT(numElements,
831 llvm::ConstantInt::get(CGF.SizeTy, minElements));
832 } else if (numElementsWidth > sizeWidth) {
833 // The other existing overflow subsumes this check.
834 // We do an unsigned comparison, since any signed value < -1 is
835 // taken care of either above or below.
836 hasOverflow = CGF.Builder.CreateOr(hasOverflow,
837 CGF.Builder.CreateICmpULT(numElements,
838 llvm::ConstantInt::get(CGF.SizeTy, minElements)));
844 // Multiply by the type size if necessary. This multiplier
845 // includes all the factors for nested arrays.
847 // This step also causes numElements to be scaled up by the
848 // nested-array factor if necessary. Overflow on this computation
849 // can be ignored because the result shouldn't be used if
851 if (typeSizeMultiplier != 1) {
852 llvm::Value *umul_with_overflow
853 = CGF.CGM.getIntrinsic(llvm::Intrinsic::umul_with_overflow, CGF.SizeTy);
856 llvm::ConstantInt::get(CGF.SizeTy, typeSizeMultiplier);
857 llvm::Value *result =
858 CGF.Builder.CreateCall(umul_with_overflow, {size, tsmV});
860 llvm::Value *overflowed = CGF.Builder.CreateExtractValue(result, 1);
862 hasOverflow = CGF.Builder.CreateOr(hasOverflow, overflowed);
864 hasOverflow = overflowed;
866 size = CGF.Builder.CreateExtractValue(result, 0);
868 // Also scale up numElements by the array size multiplier.
869 if (arraySizeMultiplier != 1) {
870 // If the base element type size is 1, then we can re-use the
871 // multiply we just did.
872 if (typeSize.isOne()) {
873 assert(arraySizeMultiplier == typeSizeMultiplier);
876 // Otherwise we need a separate multiply.
879 llvm::ConstantInt::get(CGF.SizeTy, arraySizeMultiplier);
880 numElements = CGF.Builder.CreateMul(numElements, asmV);
884 // numElements doesn't need to be scaled.
885 assert(arraySizeMultiplier == 1);
888 // Add in the cookie size if necessary.
889 if (cookieSize != 0) {
890 sizeWithoutCookie = size;
892 llvm::Value *uadd_with_overflow
893 = CGF.CGM.getIntrinsic(llvm::Intrinsic::uadd_with_overflow, CGF.SizeTy);
895 llvm::Value *cookieSizeV = llvm::ConstantInt::get(CGF.SizeTy, cookieSize);
896 llvm::Value *result =
897 CGF.Builder.CreateCall(uadd_with_overflow, {size, cookieSizeV});
899 llvm::Value *overflowed = CGF.Builder.CreateExtractValue(result, 1);
901 hasOverflow = CGF.Builder.CreateOr(hasOverflow, overflowed);
903 hasOverflow = overflowed;
905 size = CGF.Builder.CreateExtractValue(result, 0);
908 // If we had any possibility of dynamic overflow, make a select to
909 // overwrite 'size' with an all-ones value, which should cause
910 // operator new to throw.
912 size = CGF.Builder.CreateSelect(hasOverflow,
913 llvm::Constant::getAllOnesValue(CGF.SizeTy),
918 sizeWithoutCookie = size;
920 assert(sizeWithoutCookie && "didn't set sizeWithoutCookie?");
925 static void StoreAnyExprIntoOneUnit(CodeGenFunction &CGF, const Expr *Init,
926 QualType AllocType, Address NewPtr) {
927 // FIXME: Refactor with EmitExprAsInit.
928 switch (CGF.getEvaluationKind(AllocType)) {
930 CGF.EmitScalarInit(Init, nullptr,
931 CGF.MakeAddrLValue(NewPtr, AllocType), false);
934 CGF.EmitComplexExprIntoLValue(Init, CGF.MakeAddrLValue(NewPtr, AllocType),
937 case TEK_Aggregate: {
939 = AggValueSlot::forAddr(NewPtr, AllocType.getQualifiers(),
940 AggValueSlot::IsDestructed,
941 AggValueSlot::DoesNotNeedGCBarriers,
942 AggValueSlot::IsNotAliased);
943 CGF.EmitAggExpr(Init, Slot);
947 llvm_unreachable("bad evaluation kind");
950 void CodeGenFunction::EmitNewArrayInitializer(
951 const CXXNewExpr *E, QualType ElementType, llvm::Type *ElementTy,
952 Address BeginPtr, llvm::Value *NumElements,
953 llvm::Value *AllocSizeWithoutCookie) {
954 // If we have a type with trivial initialization and no initializer,
955 // there's nothing to do.
956 if (!E->hasInitializer())
959 Address CurPtr = BeginPtr;
961 unsigned InitListElements = 0;
963 const Expr *Init = E->getInitializer();
964 Address EndOfInit = Address::invalid();
965 QualType::DestructionKind DtorKind = ElementType.isDestructedType();
966 EHScopeStack::stable_iterator Cleanup;
967 llvm::Instruction *CleanupDominator = nullptr;
969 CharUnits ElementSize = getContext().getTypeSizeInChars(ElementType);
970 CharUnits ElementAlign =
971 BeginPtr.getAlignment().alignmentOfArrayElement(ElementSize);
973 // Attempt to perform zero-initialization using memset.
974 auto TryMemsetInitialization = [&]() -> bool {
975 // FIXME: If the type is a pointer-to-data-member under the Itanium ABI,
976 // we can initialize with a memset to -1.
977 if (!CGM.getTypes().isZeroInitializable(ElementType))
980 // Optimization: since zero initialization will just set the memory
981 // to all zeroes, generate a single memset to do it in one shot.
983 // Subtract out the size of any elements we've already initialized.
984 auto *RemainingSize = AllocSizeWithoutCookie;
985 if (InitListElements) {
986 // We know this can't overflow; we check this when doing the allocation.
987 auto *InitializedSize = llvm::ConstantInt::get(
988 RemainingSize->getType(),
989 getContext().getTypeSizeInChars(ElementType).getQuantity() *
991 RemainingSize = Builder.CreateSub(RemainingSize, InitializedSize);
994 // Create the memset.
995 Builder.CreateMemSet(CurPtr, Builder.getInt8(0), RemainingSize, false);
999 // If the initializer is an initializer list, first do the explicit elements.
1000 if (const InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
1001 // Initializing from a (braced) string literal is a special case; the init
1002 // list element does not initialize a (single) array element.
1003 if (ILE->isStringLiteralInit()) {
1004 // Initialize the initial portion of length equal to that of the string
1005 // literal. The allocation must be for at least this much; we emitted a
1006 // check for that earlier.
1008 AggValueSlot::forAddr(CurPtr, ElementType.getQualifiers(),
1009 AggValueSlot::IsDestructed,
1010 AggValueSlot::DoesNotNeedGCBarriers,
1011 AggValueSlot::IsNotAliased);
1012 EmitAggExpr(ILE->getInit(0), Slot);
1014 // Move past these elements.
1016 cast<ConstantArrayType>(ILE->getType()->getAsArrayTypeUnsafe())
1017 ->getSize().getZExtValue();
1019 Address(Builder.CreateInBoundsGEP(CurPtr.getPointer(),
1020 Builder.getSize(InitListElements),
1022 CurPtr.getAlignment().alignmentAtOffset(InitListElements *
1025 // Zero out the rest, if any remain.
1026 llvm::ConstantInt *ConstNum = dyn_cast<llvm::ConstantInt>(NumElements);
1027 if (!ConstNum || !ConstNum->equalsInt(InitListElements)) {
1028 bool OK = TryMemsetInitialization();
1030 assert(OK && "couldn't memset character type?");
1035 InitListElements = ILE->getNumInits();
1037 // If this is a multi-dimensional array new, we will initialize multiple
1038 // elements with each init list element.
1039 QualType AllocType = E->getAllocatedType();
1040 if (const ConstantArrayType *CAT = dyn_cast_or_null<ConstantArrayType>(
1041 AllocType->getAsArrayTypeUnsafe())) {
1042 ElementTy = ConvertTypeForMem(AllocType);
1043 CurPtr = Builder.CreateElementBitCast(CurPtr, ElementTy);
1044 InitListElements *= getContext().getConstantArrayElementCount(CAT);
1047 // Enter a partial-destruction Cleanup if necessary.
1048 if (needsEHCleanup(DtorKind)) {
1049 // In principle we could tell the Cleanup where we are more
1050 // directly, but the control flow can get so varied here that it
1051 // would actually be quite complex. Therefore we go through an
1053 EndOfInit = CreateTempAlloca(BeginPtr.getType(), getPointerAlign(),
1055 CleanupDominator = Builder.CreateStore(BeginPtr.getPointer(), EndOfInit);
1056 pushIrregularPartialArrayCleanup(BeginPtr.getPointer(), EndOfInit,
1057 ElementType, ElementAlign,
1058 getDestroyer(DtorKind));
1059 Cleanup = EHStack.stable_begin();
1062 CharUnits StartAlign = CurPtr.getAlignment();
1063 for (unsigned i = 0, e = ILE->getNumInits(); i != e; ++i) {
1064 // Tell the cleanup that it needs to destroy up to this
1065 // element. TODO: some of these stores can be trivially
1066 // observed to be unnecessary.
1067 if (EndOfInit.isValid()) {
1069 Builder.CreateBitCast(CurPtr.getPointer(), BeginPtr.getType());
1070 Builder.CreateStore(FinishedPtr, EndOfInit);
1072 // FIXME: If the last initializer is an incomplete initializer list for
1073 // an array, and we have an array filler, we can fold together the two
1074 // initialization loops.
1075 StoreAnyExprIntoOneUnit(*this, ILE->getInit(i),
1076 ILE->getInit(i)->getType(), CurPtr);
1077 CurPtr = Address(Builder.CreateInBoundsGEP(CurPtr.getPointer(),
1080 StartAlign.alignmentAtOffset((i + 1) * ElementSize));
1083 // The remaining elements are filled with the array filler expression.
1084 Init = ILE->getArrayFiller();
1086 // Extract the initializer for the individual array elements by pulling
1087 // out the array filler from all the nested initializer lists. This avoids
1088 // generating a nested loop for the initialization.
1089 while (Init && Init->getType()->isConstantArrayType()) {
1090 auto *SubILE = dyn_cast<InitListExpr>(Init);
1093 assert(SubILE->getNumInits() == 0 && "explicit inits in array filler?");
1094 Init = SubILE->getArrayFiller();
1097 // Switch back to initializing one base element at a time.
1098 CurPtr = Builder.CreateBitCast(CurPtr, BeginPtr.getType());
1101 // If all elements have already been initialized, skip any further
1103 llvm::ConstantInt *ConstNum = dyn_cast<llvm::ConstantInt>(NumElements);
1104 if (ConstNum && ConstNum->getZExtValue() <= InitListElements) {
1105 // If there was a Cleanup, deactivate it.
1106 if (CleanupDominator)
1107 DeactivateCleanupBlock(Cleanup, CleanupDominator);
1111 assert(Init && "have trailing elements to initialize but no initializer");
1113 // If this is a constructor call, try to optimize it out, and failing that
1114 // emit a single loop to initialize all remaining elements.
1115 if (const CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init)) {
1116 CXXConstructorDecl *Ctor = CCE->getConstructor();
1117 if (Ctor->isTrivial()) {
1118 // If new expression did not specify value-initialization, then there
1119 // is no initialization.
1120 if (!CCE->requiresZeroInitialization() || Ctor->getParent()->isEmpty())
1123 if (TryMemsetInitialization())
1127 // Store the new Cleanup position for irregular Cleanups.
1129 // FIXME: Share this cleanup with the constructor call emission rather than
1130 // having it create a cleanup of its own.
1131 if (EndOfInit.isValid())
1132 Builder.CreateStore(CurPtr.getPointer(), EndOfInit);
1134 // Emit a constructor call loop to initialize the remaining elements.
1135 if (InitListElements)
1136 NumElements = Builder.CreateSub(
1138 llvm::ConstantInt::get(NumElements->getType(), InitListElements));
1139 EmitCXXAggrConstructorCall(Ctor, NumElements, CurPtr, CCE,
1140 CCE->requiresZeroInitialization());
1144 // If this is value-initialization, we can usually use memset.
1145 ImplicitValueInitExpr IVIE(ElementType);
1146 if (isa<ImplicitValueInitExpr>(Init)) {
1147 if (TryMemsetInitialization())
1150 // Switch to an ImplicitValueInitExpr for the element type. This handles
1151 // only one case: multidimensional array new of pointers to members. In
1152 // all other cases, we already have an initializer for the array element.
1156 // At this point we should have found an initializer for the individual
1157 // elements of the array.
1158 assert(getContext().hasSameUnqualifiedType(ElementType, Init->getType()) &&
1159 "got wrong type of element to initialize");
1161 // If we have an empty initializer list, we can usually use memset.
1162 if (auto *ILE = dyn_cast<InitListExpr>(Init))
1163 if (ILE->getNumInits() == 0 && TryMemsetInitialization())
1166 // If we have a struct whose every field is value-initialized, we can
1167 // usually use memset.
1168 if (auto *ILE = dyn_cast<InitListExpr>(Init)) {
1169 if (const RecordType *RType = ILE->getType()->getAs<RecordType>()) {
1170 if (RType->getDecl()->isStruct()) {
1171 unsigned NumElements = 0;
1172 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(RType->getDecl()))
1173 NumElements = CXXRD->getNumBases();
1174 for (auto *Field : RType->getDecl()->fields())
1175 if (!Field->isUnnamedBitfield())
1177 // FIXME: Recurse into nested InitListExprs.
1178 if (ILE->getNumInits() == NumElements)
1179 for (unsigned i = 0, e = ILE->getNumInits(); i != e; ++i)
1180 if (!isa<ImplicitValueInitExpr>(ILE->getInit(i)))
1182 if (ILE->getNumInits() == NumElements && TryMemsetInitialization())
1188 // Create the loop blocks.
1189 llvm::BasicBlock *EntryBB = Builder.GetInsertBlock();
1190 llvm::BasicBlock *LoopBB = createBasicBlock("new.loop");
1191 llvm::BasicBlock *ContBB = createBasicBlock("new.loop.end");
1193 // Find the end of the array, hoisted out of the loop.
1194 llvm::Value *EndPtr =
1195 Builder.CreateInBoundsGEP(BeginPtr.getPointer(), NumElements, "array.end");
1197 // If the number of elements isn't constant, we have to now check if there is
1198 // anything left to initialize.
1200 llvm::Value *IsEmpty =
1201 Builder.CreateICmpEQ(CurPtr.getPointer(), EndPtr, "array.isempty");
1202 Builder.CreateCondBr(IsEmpty, ContBB, LoopBB);
1208 // Set up the current-element phi.
1209 llvm::PHINode *CurPtrPhi =
1210 Builder.CreatePHI(CurPtr.getType(), 2, "array.cur");
1211 CurPtrPhi->addIncoming(CurPtr.getPointer(), EntryBB);
1213 CurPtr = Address(CurPtrPhi, ElementAlign);
1215 // Store the new Cleanup position for irregular Cleanups.
1216 if (EndOfInit.isValid())
1217 Builder.CreateStore(CurPtr.getPointer(), EndOfInit);
1219 // Enter a partial-destruction Cleanup if necessary.
1220 if (!CleanupDominator && needsEHCleanup(DtorKind)) {
1221 pushRegularPartialArrayCleanup(BeginPtr.getPointer(), CurPtr.getPointer(),
1222 ElementType, ElementAlign,
1223 getDestroyer(DtorKind));
1224 Cleanup = EHStack.stable_begin();
1225 CleanupDominator = Builder.CreateUnreachable();
1228 // Emit the initializer into this element.
1229 StoreAnyExprIntoOneUnit(*this, Init, Init->getType(), CurPtr);
1231 // Leave the Cleanup if we entered one.
1232 if (CleanupDominator) {
1233 DeactivateCleanupBlock(Cleanup, CleanupDominator);
1234 CleanupDominator->eraseFromParent();
1237 // Advance to the next element by adjusting the pointer type as necessary.
1238 llvm::Value *NextPtr =
1239 Builder.CreateConstInBoundsGEP1_32(ElementTy, CurPtr.getPointer(), 1,
1242 // Check whether we've gotten to the end of the array and, if so,
1244 llvm::Value *IsEnd = Builder.CreateICmpEQ(NextPtr, EndPtr, "array.atend");
1245 Builder.CreateCondBr(IsEnd, ContBB, LoopBB);
1246 CurPtrPhi->addIncoming(NextPtr, Builder.GetInsertBlock());
1251 static void EmitNewInitializer(CodeGenFunction &CGF, const CXXNewExpr *E,
1252 QualType ElementType, llvm::Type *ElementTy,
1253 Address NewPtr, llvm::Value *NumElements,
1254 llvm::Value *AllocSizeWithoutCookie) {
1255 ApplyDebugLocation DL(CGF, E);
1257 CGF.EmitNewArrayInitializer(E, ElementType, ElementTy, NewPtr, NumElements,
1258 AllocSizeWithoutCookie);
1259 else if (const Expr *Init = E->getInitializer())
1260 StoreAnyExprIntoOneUnit(CGF, Init, E->getAllocatedType(), NewPtr);
1263 /// Emit a call to an operator new or operator delete function, as implicitly
1264 /// created by new-expressions and delete-expressions.
1265 static RValue EmitNewDeleteCall(CodeGenFunction &CGF,
1266 const FunctionDecl *CalleeDecl,
1267 const FunctionProtoType *CalleeType,
1268 const CallArgList &Args) {
1269 llvm::Instruction *CallOrInvoke;
1270 llvm::Constant *CalleePtr = CGF.CGM.GetAddrOfFunction(CalleeDecl);
1271 CGCallee Callee = CGCallee::forDirect(CalleePtr, CalleeDecl);
1273 CGF.EmitCall(CGF.CGM.getTypes().arrangeFreeFunctionCall(
1274 Args, CalleeType, /*chainCall=*/false),
1275 Callee, ReturnValueSlot(), Args, &CallOrInvoke);
1277 /// C++1y [expr.new]p10:
1278 /// [In a new-expression,] an implementation is allowed to omit a call
1279 /// to a replaceable global allocation function.
1281 /// We model such elidable calls with the 'builtin' attribute.
1282 llvm::Function *Fn = dyn_cast<llvm::Function>(CalleePtr);
1283 if (CalleeDecl->isReplaceableGlobalAllocationFunction() &&
1284 Fn && Fn->hasFnAttribute(llvm::Attribute::NoBuiltin)) {
1285 // FIXME: Add addAttribute to CallSite.
1286 if (llvm::CallInst *CI = dyn_cast<llvm::CallInst>(CallOrInvoke))
1287 CI->addAttribute(llvm::AttributeList::FunctionIndex,
1288 llvm::Attribute::Builtin);
1289 else if (llvm::InvokeInst *II = dyn_cast<llvm::InvokeInst>(CallOrInvoke))
1290 II->addAttribute(llvm::AttributeList::FunctionIndex,
1291 llvm::Attribute::Builtin);
1293 llvm_unreachable("unexpected kind of call instruction");
1299 RValue CodeGenFunction::EmitBuiltinNewDeleteCall(const FunctionProtoType *Type,
1303 const Stmt *ArgS = Arg;
1304 EmitCallArgs(Args, *Type->param_type_begin(), llvm::makeArrayRef(ArgS));
1305 // Find the allocation or deallocation function that we're calling.
1306 ASTContext &Ctx = getContext();
1307 DeclarationName Name = Ctx.DeclarationNames
1308 .getCXXOperatorName(IsDelete ? OO_Delete : OO_New);
1309 for (auto *Decl : Ctx.getTranslationUnitDecl()->lookup(Name))
1310 if (auto *FD = dyn_cast<FunctionDecl>(Decl))
1311 if (Ctx.hasSameType(FD->getType(), QualType(Type, 0)))
1312 return EmitNewDeleteCall(*this, cast<FunctionDecl>(Decl), Type, Args);
1313 llvm_unreachable("predeclared global operator new/delete is missing");
1317 /// The parameters to pass to a usual operator delete.
1318 struct UsualDeleteParams {
1319 bool DestroyingDelete = false;
1321 bool Alignment = false;
1325 static UsualDeleteParams getUsualDeleteParams(const FunctionDecl *FD) {
1326 UsualDeleteParams Params;
1328 const FunctionProtoType *FPT = FD->getType()->castAs<FunctionProtoType>();
1329 auto AI = FPT->param_type_begin(), AE = FPT->param_type_end();
1331 // The first argument is always a void*.
1334 // The next parameter may be a std::destroying_delete_t.
1335 if (FD->isDestroyingOperatorDelete()) {
1336 Params.DestroyingDelete = true;
1341 // Figure out what other parameters we should be implicitly passing.
1342 if (AI != AE && (*AI)->isIntegerType()) {
1347 if (AI != AE && (*AI)->isAlignValT()) {
1348 Params.Alignment = true;
1352 assert(AI == AE && "unexpected usual deallocation function parameter");
1357 /// A cleanup to call the given 'operator delete' function upon abnormal
1358 /// exit from a new expression. Templated on a traits type that deals with
1359 /// ensuring that the arguments dominate the cleanup if necessary.
1360 template<typename Traits>
1361 class CallDeleteDuringNew final : public EHScopeStack::Cleanup {
1362 /// Type used to hold llvm::Value*s.
1363 typedef typename Traits::ValueTy ValueTy;
1364 /// Type used to hold RValues.
1365 typedef typename Traits::RValueTy RValueTy;
1366 struct PlacementArg {
1371 unsigned NumPlacementArgs : 31;
1372 unsigned PassAlignmentToPlacementDelete : 1;
1373 const FunctionDecl *OperatorDelete;
1376 CharUnits AllocAlign;
1378 PlacementArg *getPlacementArgs() {
1379 return reinterpret_cast<PlacementArg *>(this + 1);
1383 static size_t getExtraSize(size_t NumPlacementArgs) {
1384 return NumPlacementArgs * sizeof(PlacementArg);
1387 CallDeleteDuringNew(size_t NumPlacementArgs,
1388 const FunctionDecl *OperatorDelete, ValueTy Ptr,
1389 ValueTy AllocSize, bool PassAlignmentToPlacementDelete,
1390 CharUnits AllocAlign)
1391 : NumPlacementArgs(NumPlacementArgs),
1392 PassAlignmentToPlacementDelete(PassAlignmentToPlacementDelete),
1393 OperatorDelete(OperatorDelete), Ptr(Ptr), AllocSize(AllocSize),
1394 AllocAlign(AllocAlign) {}
1396 void setPlacementArg(unsigned I, RValueTy Arg, QualType Type) {
1397 assert(I < NumPlacementArgs && "index out of range");
1398 getPlacementArgs()[I] = {Arg, Type};
1401 void Emit(CodeGenFunction &CGF, Flags flags) override {
1402 const FunctionProtoType *FPT =
1403 OperatorDelete->getType()->getAs<FunctionProtoType>();
1404 CallArgList DeleteArgs;
1406 // The first argument is always a void* (or C* for a destroying operator
1407 // delete for class type C).
1408 DeleteArgs.add(Traits::get(CGF, Ptr), FPT->getParamType(0));
1410 // Figure out what other parameters we should be implicitly passing.
1411 UsualDeleteParams Params;
1412 if (NumPlacementArgs) {
1413 // A placement deallocation function is implicitly passed an alignment
1414 // if the placement allocation function was, but is never passed a size.
1415 Params.Alignment = PassAlignmentToPlacementDelete;
1417 // For a non-placement new-expression, 'operator delete' can take a
1418 // size and/or an alignment if it has the right parameters.
1419 Params = getUsualDeleteParams(OperatorDelete);
1422 assert(!Params.DestroyingDelete &&
1423 "should not call destroying delete in a new-expression");
1425 // The second argument can be a std::size_t (for non-placement delete).
1427 DeleteArgs.add(Traits::get(CGF, AllocSize),
1428 CGF.getContext().getSizeType());
1430 // The next (second or third) argument can be a std::align_val_t, which
1431 // is an enum whose underlying type is std::size_t.
1432 // FIXME: Use the right type as the parameter type. Note that in a call
1433 // to operator delete(size_t, ...), we may not have it available.
1434 if (Params.Alignment)
1435 DeleteArgs.add(RValue::get(llvm::ConstantInt::get(
1436 CGF.SizeTy, AllocAlign.getQuantity())),
1437 CGF.getContext().getSizeType());
1439 // Pass the rest of the arguments, which must match exactly.
1440 for (unsigned I = 0; I != NumPlacementArgs; ++I) {
1441 auto Arg = getPlacementArgs()[I];
1442 DeleteArgs.add(Traits::get(CGF, Arg.ArgValue), Arg.ArgType);
1445 // Call 'operator delete'.
1446 EmitNewDeleteCall(CGF, OperatorDelete, FPT, DeleteArgs);
1451 /// Enter a cleanup to call 'operator delete' if the initializer in a
1452 /// new-expression throws.
1453 static void EnterNewDeleteCleanup(CodeGenFunction &CGF,
1454 const CXXNewExpr *E,
1456 llvm::Value *AllocSize,
1457 CharUnits AllocAlign,
1458 const CallArgList &NewArgs) {
1459 unsigned NumNonPlacementArgs = E->passAlignment() ? 2 : 1;
1461 // If we're not inside a conditional branch, then the cleanup will
1462 // dominate and we can do the easier (and more efficient) thing.
1463 if (!CGF.isInConditionalBranch()) {
1464 struct DirectCleanupTraits {
1465 typedef llvm::Value *ValueTy;
1466 typedef RValue RValueTy;
1467 static RValue get(CodeGenFunction &, ValueTy V) { return RValue::get(V); }
1468 static RValue get(CodeGenFunction &, RValueTy V) { return V; }
1471 typedef CallDeleteDuringNew<DirectCleanupTraits> DirectCleanup;
1473 DirectCleanup *Cleanup = CGF.EHStack
1474 .pushCleanupWithExtra<DirectCleanup>(EHCleanup,
1475 E->getNumPlacementArgs(),
1476 E->getOperatorDelete(),
1477 NewPtr.getPointer(),
1481 for (unsigned I = 0, N = E->getNumPlacementArgs(); I != N; ++I) {
1482 auto &Arg = NewArgs[I + NumNonPlacementArgs];
1483 Cleanup->setPlacementArg(I, Arg.RV, Arg.Ty);
1489 // Otherwise, we need to save all this stuff.
1490 DominatingValue<RValue>::saved_type SavedNewPtr =
1491 DominatingValue<RValue>::save(CGF, RValue::get(NewPtr.getPointer()));
1492 DominatingValue<RValue>::saved_type SavedAllocSize =
1493 DominatingValue<RValue>::save(CGF, RValue::get(AllocSize));
1495 struct ConditionalCleanupTraits {
1496 typedef DominatingValue<RValue>::saved_type ValueTy;
1497 typedef DominatingValue<RValue>::saved_type RValueTy;
1498 static RValue get(CodeGenFunction &CGF, ValueTy V) {
1499 return V.restore(CGF);
1502 typedef CallDeleteDuringNew<ConditionalCleanupTraits> ConditionalCleanup;
1504 ConditionalCleanup *Cleanup = CGF.EHStack
1505 .pushCleanupWithExtra<ConditionalCleanup>(EHCleanup,
1506 E->getNumPlacementArgs(),
1507 E->getOperatorDelete(),
1512 for (unsigned I = 0, N = E->getNumPlacementArgs(); I != N; ++I) {
1513 auto &Arg = NewArgs[I + NumNonPlacementArgs];
1514 Cleanup->setPlacementArg(I, DominatingValue<RValue>::save(CGF, Arg.RV),
1518 CGF.initFullExprCleanup();
1521 llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
1522 // The element type being allocated.
1523 QualType allocType = getContext().getBaseElementType(E->getAllocatedType());
1525 // 1. Build a call to the allocation function.
1526 FunctionDecl *allocator = E->getOperatorNew();
1528 // If there is a brace-initializer, cannot allocate fewer elements than inits.
1529 unsigned minElements = 0;
1530 if (E->isArray() && E->hasInitializer()) {
1531 const InitListExpr *ILE = dyn_cast<InitListExpr>(E->getInitializer());
1532 if (ILE && ILE->isStringLiteralInit())
1534 cast<ConstantArrayType>(ILE->getType()->getAsArrayTypeUnsafe())
1535 ->getSize().getZExtValue();
1537 minElements = ILE->getNumInits();
1540 llvm::Value *numElements = nullptr;
1541 llvm::Value *allocSizeWithoutCookie = nullptr;
1542 llvm::Value *allocSize =
1543 EmitCXXNewAllocSize(*this, E, minElements, numElements,
1544 allocSizeWithoutCookie);
1545 CharUnits allocAlign = getContext().getTypeAlignInChars(allocType);
1547 // Emit the allocation call. If the allocator is a global placement
1548 // operator, just "inline" it directly.
1549 Address allocation = Address::invalid();
1550 CallArgList allocatorArgs;
1551 if (allocator->isReservedGlobalPlacementOperator()) {
1552 assert(E->getNumPlacementArgs() == 1);
1553 const Expr *arg = *E->placement_arguments().begin();
1555 LValueBaseInfo BaseInfo;
1556 allocation = EmitPointerWithAlignment(arg, &BaseInfo);
1558 // The pointer expression will, in many cases, be an opaque void*.
1559 // In these cases, discard the computed alignment and use the
1560 // formal alignment of the allocated type.
1561 if (BaseInfo.getAlignmentSource() != AlignmentSource::Decl)
1562 allocation = Address(allocation.getPointer(), allocAlign);
1564 // Set up allocatorArgs for the call to operator delete if it's not
1565 // the reserved global operator.
1566 if (E->getOperatorDelete() &&
1567 !E->getOperatorDelete()->isReservedGlobalPlacementOperator()) {
1568 allocatorArgs.add(RValue::get(allocSize), getContext().getSizeType());
1569 allocatorArgs.add(RValue::get(allocation.getPointer()), arg->getType());
1573 const FunctionProtoType *allocatorType =
1574 allocator->getType()->castAs<FunctionProtoType>();
1575 unsigned ParamsToSkip = 0;
1577 // The allocation size is the first argument.
1578 QualType sizeType = getContext().getSizeType();
1579 allocatorArgs.add(RValue::get(allocSize), sizeType);
1582 if (allocSize != allocSizeWithoutCookie) {
1583 CharUnits cookieAlign = getSizeAlign(); // FIXME: Ask the ABI.
1584 allocAlign = std::max(allocAlign, cookieAlign);
1587 // The allocation alignment may be passed as the second argument.
1588 if (E->passAlignment()) {
1589 QualType AlignValT = sizeType;
1590 if (allocatorType->getNumParams() > 1) {
1591 AlignValT = allocatorType->getParamType(1);
1592 assert(getContext().hasSameUnqualifiedType(
1593 AlignValT->castAs<EnumType>()->getDecl()->getIntegerType(),
1595 "wrong type for alignment parameter");
1598 // Corner case, passing alignment to 'operator new(size_t, ...)'.
1599 assert(allocator->isVariadic() && "can't pass alignment to allocator");
1602 RValue::get(llvm::ConstantInt::get(SizeTy, allocAlign.getQuantity())),
1606 // FIXME: Why do we not pass a CalleeDecl here?
1607 EmitCallArgs(allocatorArgs, allocatorType, E->placement_arguments(),
1608 /*AC*/AbstractCallee(), /*ParamsToSkip*/ParamsToSkip);
1611 EmitNewDeleteCall(*this, allocator, allocatorType, allocatorArgs);
1613 // If this was a call to a global replaceable allocation function that does
1614 // not take an alignment argument, the allocator is known to produce
1615 // storage that's suitably aligned for any object that fits, up to a known
1616 // threshold. Otherwise assume it's suitably aligned for the allocated type.
1617 CharUnits allocationAlign = allocAlign;
1618 if (!E->passAlignment() &&
1619 allocator->isReplaceableGlobalAllocationFunction()) {
1620 unsigned AllocatorAlign = llvm::PowerOf2Floor(std::min<uint64_t>(
1621 Target.getNewAlign(), getContext().getTypeSize(allocType)));
1622 allocationAlign = std::max(
1623 allocationAlign, getContext().toCharUnitsFromBits(AllocatorAlign));
1626 allocation = Address(RV.getScalarVal(), allocationAlign);
1629 // Emit a null check on the allocation result if the allocation
1630 // function is allowed to return null (because it has a non-throwing
1631 // exception spec or is the reserved placement new) and we have an
1632 // interesting initializer.
1633 bool nullCheck = E->shouldNullCheckAllocation(getContext()) &&
1634 (!allocType.isPODType(getContext()) || E->hasInitializer());
1636 llvm::BasicBlock *nullCheckBB = nullptr;
1637 llvm::BasicBlock *contBB = nullptr;
1639 // The null-check means that the initializer is conditionally
1641 ConditionalEvaluation conditional(*this);
1644 conditional.begin(*this);
1646 nullCheckBB = Builder.GetInsertBlock();
1647 llvm::BasicBlock *notNullBB = createBasicBlock("new.notnull");
1648 contBB = createBasicBlock("new.cont");
1650 llvm::Value *isNull =
1651 Builder.CreateIsNull(allocation.getPointer(), "new.isnull");
1652 Builder.CreateCondBr(isNull, contBB, notNullBB);
1653 EmitBlock(notNullBB);
1656 // If there's an operator delete, enter a cleanup to call it if an
1657 // exception is thrown.
1658 EHScopeStack::stable_iterator operatorDeleteCleanup;
1659 llvm::Instruction *cleanupDominator = nullptr;
1660 if (E->getOperatorDelete() &&
1661 !E->getOperatorDelete()->isReservedGlobalPlacementOperator()) {
1662 EnterNewDeleteCleanup(*this, E, allocation, allocSize, allocAlign,
1664 operatorDeleteCleanup = EHStack.stable_begin();
1665 cleanupDominator = Builder.CreateUnreachable();
1668 assert((allocSize == allocSizeWithoutCookie) ==
1669 CalculateCookiePadding(*this, E).isZero());
1670 if (allocSize != allocSizeWithoutCookie) {
1671 assert(E->isArray());
1672 allocation = CGM.getCXXABI().InitializeArrayCookie(*this, allocation,
1677 llvm::Type *elementTy = ConvertTypeForMem(allocType);
1678 Address result = Builder.CreateElementBitCast(allocation, elementTy);
1680 // Passing pointer through invariant.group.barrier to avoid propagation of
1681 // vptrs information which may be included in previous type.
1682 // To not break LTO with different optimizations levels, we do it regardless
1683 // of optimization level.
1684 if (CGM.getCodeGenOpts().StrictVTablePointers &&
1685 allocator->isReservedGlobalPlacementOperator())
1686 result = Address(Builder.CreateInvariantGroupBarrier(result.getPointer()),
1687 result.getAlignment());
1689 EmitNewInitializer(*this, E, allocType, elementTy, result, numElements,
1690 allocSizeWithoutCookie);
1692 // NewPtr is a pointer to the base element type. If we're
1693 // allocating an array of arrays, we'll need to cast back to the
1694 // array pointer type.
1695 llvm::Type *resultType = ConvertTypeForMem(E->getType());
1696 if (result.getType() != resultType)
1697 result = Builder.CreateBitCast(result, resultType);
1700 // Deactivate the 'operator delete' cleanup if we finished
1702 if (operatorDeleteCleanup.isValid()) {
1703 DeactivateCleanupBlock(operatorDeleteCleanup, cleanupDominator);
1704 cleanupDominator->eraseFromParent();
1707 llvm::Value *resultPtr = result.getPointer();
1709 conditional.end(*this);
1711 llvm::BasicBlock *notNullBB = Builder.GetInsertBlock();
1714 llvm::PHINode *PHI = Builder.CreatePHI(resultPtr->getType(), 2);
1715 PHI->addIncoming(resultPtr, notNullBB);
1716 PHI->addIncoming(llvm::Constant::getNullValue(resultPtr->getType()),
1725 void CodeGenFunction::EmitDeleteCall(const FunctionDecl *DeleteFD,
1726 llvm::Value *Ptr, QualType DeleteTy,
1727 llvm::Value *NumElements,
1728 CharUnits CookieSize) {
1729 assert((!NumElements && CookieSize.isZero()) ||
1730 DeleteFD->getOverloadedOperator() == OO_Array_Delete);
1732 const FunctionProtoType *DeleteFTy =
1733 DeleteFD->getType()->getAs<FunctionProtoType>();
1735 CallArgList DeleteArgs;
1737 auto Params = getUsualDeleteParams(DeleteFD);
1738 auto ParamTypeIt = DeleteFTy->param_type_begin();
1740 // Pass the pointer itself.
1741 QualType ArgTy = *ParamTypeIt++;
1742 llvm::Value *DeletePtr = Builder.CreateBitCast(Ptr, ConvertType(ArgTy));
1743 DeleteArgs.add(RValue::get(DeletePtr), ArgTy);
1745 // Pass the std::destroying_delete tag if present.
1746 if (Params.DestroyingDelete) {
1747 QualType DDTag = *ParamTypeIt++;
1748 // Just pass an 'undef'. We expect the tag type to be an empty struct.
1749 auto *V = llvm::UndefValue::get(getTypes().ConvertType(DDTag));
1750 DeleteArgs.add(RValue::get(V), DDTag);
1753 // Pass the size if the delete function has a size_t parameter.
1755 QualType SizeType = *ParamTypeIt++;
1756 CharUnits DeleteTypeSize = getContext().getTypeSizeInChars(DeleteTy);
1757 llvm::Value *Size = llvm::ConstantInt::get(ConvertType(SizeType),
1758 DeleteTypeSize.getQuantity());
1760 // For array new, multiply by the number of elements.
1762 Size = Builder.CreateMul(Size, NumElements);
1764 // If there is a cookie, add the cookie size.
1765 if (!CookieSize.isZero())
1766 Size = Builder.CreateAdd(
1767 Size, llvm::ConstantInt::get(SizeTy, CookieSize.getQuantity()));
1769 DeleteArgs.add(RValue::get(Size), SizeType);
1772 // Pass the alignment if the delete function has an align_val_t parameter.
1773 if (Params.Alignment) {
1774 QualType AlignValType = *ParamTypeIt++;
1775 CharUnits DeleteTypeAlign = getContext().toCharUnitsFromBits(
1776 getContext().getTypeAlignIfKnown(DeleteTy));
1777 llvm::Value *Align = llvm::ConstantInt::get(ConvertType(AlignValType),
1778 DeleteTypeAlign.getQuantity());
1779 DeleteArgs.add(RValue::get(Align), AlignValType);
1782 assert(ParamTypeIt == DeleteFTy->param_type_end() &&
1783 "unknown parameter to usual delete function");
1785 // Emit the call to delete.
1786 EmitNewDeleteCall(*this, DeleteFD, DeleteFTy, DeleteArgs);
1790 /// Calls the given 'operator delete' on a single object.
1791 struct CallObjectDelete final : EHScopeStack::Cleanup {
1793 const FunctionDecl *OperatorDelete;
1794 QualType ElementType;
1796 CallObjectDelete(llvm::Value *Ptr,
1797 const FunctionDecl *OperatorDelete,
1798 QualType ElementType)
1799 : Ptr(Ptr), OperatorDelete(OperatorDelete), ElementType(ElementType) {}
1801 void Emit(CodeGenFunction &CGF, Flags flags) override {
1802 CGF.EmitDeleteCall(OperatorDelete, Ptr, ElementType);
1808 CodeGenFunction::pushCallObjectDeleteCleanup(const FunctionDecl *OperatorDelete,
1809 llvm::Value *CompletePtr,
1810 QualType ElementType) {
1811 EHStack.pushCleanup<CallObjectDelete>(NormalAndEHCleanup, CompletePtr,
1812 OperatorDelete, ElementType);
1815 /// Emit the code for deleting a single object with a destroying operator
1816 /// delete. If the element type has a non-virtual destructor, Ptr has already
1817 /// been converted to the type of the parameter of 'operator delete'. Otherwise
1818 /// Ptr points to an object of the static type.
1819 static void EmitDestroyingObjectDelete(CodeGenFunction &CGF,
1820 const CXXDeleteExpr *DE, Address Ptr,
1821 QualType ElementType) {
1822 auto *Dtor = ElementType->getAsCXXRecordDecl()->getDestructor();
1823 if (Dtor && Dtor->isVirtual())
1824 CGF.CGM.getCXXABI().emitVirtualObjectDelete(CGF, DE, Ptr, ElementType,
1827 CGF.EmitDeleteCall(DE->getOperatorDelete(), Ptr.getPointer(), ElementType);
1830 /// Emit the code for deleting a single object.
1831 static void EmitObjectDelete(CodeGenFunction &CGF,
1832 const CXXDeleteExpr *DE,
1834 QualType ElementType) {
1835 // C++11 [expr.delete]p3:
1836 // If the static type of the object to be deleted is different from its
1837 // dynamic type, the static type shall be a base class of the dynamic type
1838 // of the object to be deleted and the static type shall have a virtual
1839 // destructor or the behavior is undefined.
1840 CGF.EmitTypeCheck(CodeGenFunction::TCK_MemberCall,
1841 DE->getExprLoc(), Ptr.getPointer(),
1844 const FunctionDecl *OperatorDelete = DE->getOperatorDelete();
1845 assert(!OperatorDelete->isDestroyingOperatorDelete());
1847 // Find the destructor for the type, if applicable. If the
1848 // destructor is virtual, we'll just emit the vcall and return.
1849 const CXXDestructorDecl *Dtor = nullptr;
1850 if (const RecordType *RT = ElementType->getAs<RecordType>()) {
1851 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
1852 if (RD->hasDefinition() && !RD->hasTrivialDestructor()) {
1853 Dtor = RD->getDestructor();
1855 if (Dtor->isVirtual()) {
1856 CGF.CGM.getCXXABI().emitVirtualObjectDelete(CGF, DE, Ptr, ElementType,
1863 // Make sure that we call delete even if the dtor throws.
1864 // This doesn't have to a conditional cleanup because we're going
1865 // to pop it off in a second.
1866 CGF.EHStack.pushCleanup<CallObjectDelete>(NormalAndEHCleanup,
1868 OperatorDelete, ElementType);
1871 CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
1872 /*ForVirtualBase=*/false,
1873 /*Delegating=*/false,
1875 else if (auto Lifetime = ElementType.getObjCLifetime()) {
1877 case Qualifiers::OCL_None:
1878 case Qualifiers::OCL_ExplicitNone:
1879 case Qualifiers::OCL_Autoreleasing:
1882 case Qualifiers::OCL_Strong:
1883 CGF.EmitARCDestroyStrong(Ptr, ARCPreciseLifetime);
1886 case Qualifiers::OCL_Weak:
1887 CGF.EmitARCDestroyWeak(Ptr);
1892 CGF.PopCleanupBlock();
1896 /// Calls the given 'operator delete' on an array of objects.
1897 struct CallArrayDelete final : EHScopeStack::Cleanup {
1899 const FunctionDecl *OperatorDelete;
1900 llvm::Value *NumElements;
1901 QualType ElementType;
1902 CharUnits CookieSize;
1904 CallArrayDelete(llvm::Value *Ptr,
1905 const FunctionDecl *OperatorDelete,
1906 llvm::Value *NumElements,
1907 QualType ElementType,
1908 CharUnits CookieSize)
1909 : Ptr(Ptr), OperatorDelete(OperatorDelete), NumElements(NumElements),
1910 ElementType(ElementType), CookieSize(CookieSize) {}
1912 void Emit(CodeGenFunction &CGF, Flags flags) override {
1913 CGF.EmitDeleteCall(OperatorDelete, Ptr, ElementType, NumElements,
1919 /// Emit the code for deleting an array of objects.
1920 static void EmitArrayDelete(CodeGenFunction &CGF,
1921 const CXXDeleteExpr *E,
1923 QualType elementType) {
1924 llvm::Value *numElements = nullptr;
1925 llvm::Value *allocatedPtr = nullptr;
1926 CharUnits cookieSize;
1927 CGF.CGM.getCXXABI().ReadArrayCookie(CGF, deletedPtr, E, elementType,
1928 numElements, allocatedPtr, cookieSize);
1930 assert(allocatedPtr && "ReadArrayCookie didn't set allocated pointer");
1932 // Make sure that we call delete even if one of the dtors throws.
1933 const FunctionDecl *operatorDelete = E->getOperatorDelete();
1934 CGF.EHStack.pushCleanup<CallArrayDelete>(NormalAndEHCleanup,
1935 allocatedPtr, operatorDelete,
1936 numElements, elementType,
1939 // Destroy the elements.
1940 if (QualType::DestructionKind dtorKind = elementType.isDestructedType()) {
1941 assert(numElements && "no element count for a type with a destructor!");
1943 CharUnits elementSize = CGF.getContext().getTypeSizeInChars(elementType);
1944 CharUnits elementAlign =
1945 deletedPtr.getAlignment().alignmentOfArrayElement(elementSize);
1947 llvm::Value *arrayBegin = deletedPtr.getPointer();
1948 llvm::Value *arrayEnd =
1949 CGF.Builder.CreateInBoundsGEP(arrayBegin, numElements, "delete.end");
1951 // Note that it is legal to allocate a zero-length array, and we
1952 // can never fold the check away because the length should always
1953 // come from a cookie.
1954 CGF.emitArrayDestroy(arrayBegin, arrayEnd, elementType, elementAlign,
1955 CGF.getDestroyer(dtorKind),
1956 /*checkZeroLength*/ true,
1957 CGF.needsEHCleanup(dtorKind));
1960 // Pop the cleanup block.
1961 CGF.PopCleanupBlock();
1964 void CodeGenFunction::EmitCXXDeleteExpr(const CXXDeleteExpr *E) {
1965 const Expr *Arg = E->getArgument();
1966 Address Ptr = EmitPointerWithAlignment(Arg);
1968 // Null check the pointer.
1969 llvm::BasicBlock *DeleteNotNull = createBasicBlock("delete.notnull");
1970 llvm::BasicBlock *DeleteEnd = createBasicBlock("delete.end");
1972 llvm::Value *IsNull = Builder.CreateIsNull(Ptr.getPointer(), "isnull");
1974 Builder.CreateCondBr(IsNull, DeleteEnd, DeleteNotNull);
1975 EmitBlock(DeleteNotNull);
1977 QualType DeleteTy = E->getDestroyedType();
1979 // A destroying operator delete overrides the entire operation of the
1980 // delete expression.
1981 if (E->getOperatorDelete()->isDestroyingOperatorDelete()) {
1982 EmitDestroyingObjectDelete(*this, E, Ptr, DeleteTy);
1983 EmitBlock(DeleteEnd);
1987 // We might be deleting a pointer to array. If so, GEP down to the
1988 // first non-array element.
1989 // (this assumes that A(*)[3][7] is converted to [3 x [7 x %A]]*)
1990 if (DeleteTy->isConstantArrayType()) {
1991 llvm::Value *Zero = Builder.getInt32(0);
1992 SmallVector<llvm::Value*,8> GEP;
1994 GEP.push_back(Zero); // point at the outermost array
1996 // For each layer of array type we're pointing at:
1997 while (const ConstantArrayType *Arr
1998 = getContext().getAsConstantArrayType(DeleteTy)) {
1999 // 1. Unpeel the array type.
2000 DeleteTy = Arr->getElementType();
2002 // 2. GEP to the first element of the array.
2003 GEP.push_back(Zero);
2006 Ptr = Address(Builder.CreateInBoundsGEP(Ptr.getPointer(), GEP, "del.first"),
2007 Ptr.getAlignment());
2010 assert(ConvertTypeForMem(DeleteTy) == Ptr.getElementType());
2012 if (E->isArrayForm()) {
2013 EmitArrayDelete(*this, E, Ptr, DeleteTy);
2015 EmitObjectDelete(*this, E, Ptr, DeleteTy);
2018 EmitBlock(DeleteEnd);
2021 static bool isGLValueFromPointerDeref(const Expr *E) {
2022 E = E->IgnoreParens();
2024 if (const auto *CE = dyn_cast<CastExpr>(E)) {
2025 if (!CE->getSubExpr()->isGLValue())
2027 return isGLValueFromPointerDeref(CE->getSubExpr());
2030 if (const auto *OVE = dyn_cast<OpaqueValueExpr>(E))
2031 return isGLValueFromPointerDeref(OVE->getSourceExpr());
2033 if (const auto *BO = dyn_cast<BinaryOperator>(E))
2034 if (BO->getOpcode() == BO_Comma)
2035 return isGLValueFromPointerDeref(BO->getRHS());
2037 if (const auto *ACO = dyn_cast<AbstractConditionalOperator>(E))
2038 return isGLValueFromPointerDeref(ACO->getTrueExpr()) ||
2039 isGLValueFromPointerDeref(ACO->getFalseExpr());
2041 // C++11 [expr.sub]p1:
2042 // The expression E1[E2] is identical (by definition) to *((E1)+(E2))
2043 if (isa<ArraySubscriptExpr>(E))
2046 if (const auto *UO = dyn_cast<UnaryOperator>(E))
2047 if (UO->getOpcode() == UO_Deref)
2053 static llvm::Value *EmitTypeidFromVTable(CodeGenFunction &CGF, const Expr *E,
2054 llvm::Type *StdTypeInfoPtrTy) {
2055 // Get the vtable pointer.
2056 Address ThisPtr = CGF.EmitLValue(E).getAddress();
2058 // C++ [expr.typeid]p2:
2059 // If the glvalue expression is obtained by applying the unary * operator to
2060 // a pointer and the pointer is a null pointer value, the typeid expression
2061 // throws the std::bad_typeid exception.
2063 // However, this paragraph's intent is not clear. We choose a very generous
2064 // interpretation which implores us to consider comma operators, conditional
2065 // operators, parentheses and other such constructs.
2066 QualType SrcRecordTy = E->getType();
2067 if (CGF.CGM.getCXXABI().shouldTypeidBeNullChecked(
2068 isGLValueFromPointerDeref(E), SrcRecordTy)) {
2069 llvm::BasicBlock *BadTypeidBlock =
2070 CGF.createBasicBlock("typeid.bad_typeid");
2071 llvm::BasicBlock *EndBlock = CGF.createBasicBlock("typeid.end");
2073 llvm::Value *IsNull = CGF.Builder.CreateIsNull(ThisPtr.getPointer());
2074 CGF.Builder.CreateCondBr(IsNull, BadTypeidBlock, EndBlock);
2076 CGF.EmitBlock(BadTypeidBlock);
2077 CGF.CGM.getCXXABI().EmitBadTypeidCall(CGF);
2078 CGF.EmitBlock(EndBlock);
2081 return CGF.CGM.getCXXABI().EmitTypeid(CGF, SrcRecordTy, ThisPtr,
2085 llvm::Value *CodeGenFunction::EmitCXXTypeidExpr(const CXXTypeidExpr *E) {
2086 llvm::Type *StdTypeInfoPtrTy =
2087 ConvertType(E->getType())->getPointerTo();
2089 if (E->isTypeOperand()) {
2090 llvm::Constant *TypeInfo =
2091 CGM.GetAddrOfRTTIDescriptor(E->getTypeOperand(getContext()));
2092 return Builder.CreateBitCast(TypeInfo, StdTypeInfoPtrTy);
2095 // C++ [expr.typeid]p2:
2096 // When typeid is applied to a glvalue expression whose type is a
2097 // polymorphic class type, the result refers to a std::type_info object
2098 // representing the type of the most derived object (that is, the dynamic
2099 // type) to which the glvalue refers.
2100 if (E->isPotentiallyEvaluated())
2101 return EmitTypeidFromVTable(*this, E->getExprOperand(),
2104 QualType OperandTy = E->getExprOperand()->getType();
2105 return Builder.CreateBitCast(CGM.GetAddrOfRTTIDescriptor(OperandTy),
2109 static llvm::Value *EmitDynamicCastToNull(CodeGenFunction &CGF,
2111 llvm::Type *DestLTy = CGF.ConvertType(DestTy);
2112 if (DestTy->isPointerType())
2113 return llvm::Constant::getNullValue(DestLTy);
2115 /// C++ [expr.dynamic.cast]p9:
2116 /// A failed cast to reference type throws std::bad_cast
2117 if (!CGF.CGM.getCXXABI().EmitBadCastCall(CGF))
2120 CGF.EmitBlock(CGF.createBasicBlock("dynamic_cast.end"));
2121 return llvm::UndefValue::get(DestLTy);
2124 llvm::Value *CodeGenFunction::EmitDynamicCast(Address ThisAddr,
2125 const CXXDynamicCastExpr *DCE) {
2126 CGM.EmitExplicitCastExprType(DCE, this);
2127 QualType DestTy = DCE->getTypeAsWritten();
2129 if (DCE->isAlwaysNull())
2130 if (llvm::Value *T = EmitDynamicCastToNull(*this, DestTy))
2133 QualType SrcTy = DCE->getSubExpr()->getType();
2135 // C++ [expr.dynamic.cast]p7:
2136 // If T is "pointer to cv void," then the result is a pointer to the most
2137 // derived object pointed to by v.
2138 const PointerType *DestPTy = DestTy->getAs<PointerType>();
2140 bool isDynamicCastToVoid;
2141 QualType SrcRecordTy;
2142 QualType DestRecordTy;
2144 isDynamicCastToVoid = DestPTy->getPointeeType()->isVoidType();
2145 SrcRecordTy = SrcTy->castAs<PointerType>()->getPointeeType();
2146 DestRecordTy = DestPTy->getPointeeType();
2148 isDynamicCastToVoid = false;
2149 SrcRecordTy = SrcTy;
2150 DestRecordTy = DestTy->castAs<ReferenceType>()->getPointeeType();
2153 assert(SrcRecordTy->isRecordType() && "source type must be a record type!");
2155 // C++ [expr.dynamic.cast]p4:
2156 // If the value of v is a null pointer value in the pointer case, the result
2157 // is the null pointer value of type T.
2158 bool ShouldNullCheckSrcValue =
2159 CGM.getCXXABI().shouldDynamicCastCallBeNullChecked(SrcTy->isPointerType(),
2162 llvm::BasicBlock *CastNull = nullptr;
2163 llvm::BasicBlock *CastNotNull = nullptr;
2164 llvm::BasicBlock *CastEnd = createBasicBlock("dynamic_cast.end");
2166 if (ShouldNullCheckSrcValue) {
2167 CastNull = createBasicBlock("dynamic_cast.null");
2168 CastNotNull = createBasicBlock("dynamic_cast.notnull");
2170 llvm::Value *IsNull = Builder.CreateIsNull(ThisAddr.getPointer());
2171 Builder.CreateCondBr(IsNull, CastNull, CastNotNull);
2172 EmitBlock(CastNotNull);
2176 if (isDynamicCastToVoid) {
2177 Value = CGM.getCXXABI().EmitDynamicCastToVoid(*this, ThisAddr, SrcRecordTy,
2180 assert(DestRecordTy->isRecordType() &&
2181 "destination type must be a record type!");
2182 Value = CGM.getCXXABI().EmitDynamicCastCall(*this, ThisAddr, SrcRecordTy,
2183 DestTy, DestRecordTy, CastEnd);
2184 CastNotNull = Builder.GetInsertBlock();
2187 if (ShouldNullCheckSrcValue) {
2188 EmitBranch(CastEnd);
2190 EmitBlock(CastNull);
2191 EmitBranch(CastEnd);
2196 if (ShouldNullCheckSrcValue) {
2197 llvm::PHINode *PHI = Builder.CreatePHI(Value->getType(), 2);
2198 PHI->addIncoming(Value, CastNotNull);
2199 PHI->addIncoming(llvm::Constant::getNullValue(Value->getType()), CastNull);
2207 void CodeGenFunction::EmitLambdaExpr(const LambdaExpr *E, AggValueSlot Slot) {
2208 RunCleanupsScope Scope(*this);
2209 LValue SlotLV = MakeAddrLValue(Slot.getAddress(), E->getType());
2211 CXXRecordDecl::field_iterator CurField = E->getLambdaClass()->field_begin();
2212 for (LambdaExpr::const_capture_init_iterator i = E->capture_init_begin(),
2213 e = E->capture_init_end();
2214 i != e; ++i, ++CurField) {
2215 // Emit initialization
2216 LValue LV = EmitLValueForFieldInitialization(SlotLV, *CurField);
2217 if (CurField->hasCapturedVLAType()) {
2218 auto VAT = CurField->getCapturedVLAType();
2219 EmitStoreThroughLValue(RValue::get(VLASizeMap[VAT->getSizeExpr()]), LV);
2221 EmitInitializerForField(*CurField, LV, *i);