1//===--- CGExprCXX.cpp - Emit LLVM Code for C++ expressions ---------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This contains code dealing with code generation of C++ expressions
10//
11//===----------------------------------------------------------------------===//
12
13#include "CGCUDARuntime.h"
14#include "CGCXXABI.h"
15#include "CGDebugInfo.h"
16#include "CGObjCRuntime.h"
17#include "CodeGenFunction.h"
18#include "ConstantEmitter.h"
19#include "TargetInfo.h"
20#include "clang/Basic/CodeGenOptions.h"
21#include "clang/CodeGen/CGFunctionInfo.h"
22#include "llvm/IR/Intrinsics.h"
23
24using namespace clang;
25using namespace CodeGen;
26
27namespace {
28struct MemberCallInfo {
29 RequiredArgs ReqArgs;
30 // Number of prefix arguments for the call. Ignores the `this` pointer.
31 unsigned PrefixSize;
32};
33} // namespace
34
35static MemberCallInfo
36commonEmitCXXMemberOrOperatorCall(CodeGenFunction &CGF, GlobalDecl GD,
37 llvm::Value *This, llvm::Value *ImplicitParam,
38 QualType ImplicitParamTy, const CallExpr *CE,
39 CallArgList &Args, CallArgList *RtlArgs) {
40 auto *MD = cast<CXXMethodDecl>(Val: GD.getDecl());
41
42 assert(CE == nullptr || isa<CXXMemberCallExpr>(CE) ||
43 isa<CXXOperatorCallExpr>(CE));
44 assert(MD->isImplicitObjectMemberFunction() &&
45 "Trying to emit a member or operator call expr on a static method!");
46
47 // Push the this ptr.
48 const CXXRecordDecl *RD =
49 CGF.CGM.getCXXABI().getThisArgumentTypeForMethod(GD);
50 Args.add(rvalue: RValue::get(V: This), type: CGF.getTypes().DeriveThisType(RD, MD));
51
52 // If there is an implicit parameter (e.g. VTT), emit it.
53 if (ImplicitParam) {
54 Args.add(rvalue: RValue::get(V: ImplicitParam), type: ImplicitParamTy);
55 }
56
57 const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
58 RequiredArgs required = RequiredArgs::forPrototypePlus(prototype: FPT, additional: Args.size());
59 unsigned PrefixSize = Args.size() - 1;
60
61 // And the rest of the call args.
62 if (RtlArgs) {
63 // Special case: if the caller emitted the arguments right-to-left already
64 // (prior to emitting the *this argument), we're done. This happens for
65 // assignment operators.
66 Args.addFrom(other: *RtlArgs);
67 } else if (CE) {
68 // Special case: skip first argument of CXXOperatorCall (it is "this").
69 unsigned ArgsToSkip = 0;
70 if (const auto *Op = dyn_cast<CXXOperatorCallExpr>(Val: CE)) {
71 if (const auto *M = dyn_cast<CXXMethodDecl>(Val: Op->getCalleeDecl()))
72 ArgsToSkip =
73 static_cast<unsigned>(!M->isExplicitObjectMemberFunction());
74 }
75 CGF.EmitCallArgs(Args, Prototype: FPT, ArgRange: drop_begin(RangeOrContainer: CE->arguments(), N: ArgsToSkip),
76 AC: CE->getDirectCallee());
77 } else {
78 assert(
79 FPT->getNumParams() == 0 &&
80 "No CallExpr specified for function with non-zero number of arguments");
81 }
82 return {.ReqArgs: required, .PrefixSize: PrefixSize};
83}
84
85RValue CodeGenFunction::EmitCXXMemberOrOperatorCall(
86 const CXXMethodDecl *MD, const CGCallee &Callee,
87 ReturnValueSlot ReturnValue, llvm::Value *This, llvm::Value *ImplicitParam,
88 QualType ImplicitParamTy, const CallExpr *CE, CallArgList *RtlArgs,
89 llvm::CallBase **CallOrInvoke) {
90 const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
91 CallArgList Args;
92 MemberCallInfo CallInfo = commonEmitCXXMemberOrOperatorCall(
93 CGF&: *this, GD: MD, This, ImplicitParam, ImplicitParamTy, CE, Args, RtlArgs);
94 auto &FnInfo = CGM.getTypes().arrangeCXXMethodCall(
95 args: Args, type: FPT, required: CallInfo.ReqArgs, numPrefixArgs: CallInfo.PrefixSize);
96 return EmitCall(CallInfo: FnInfo, Callee, ReturnValue, Args, CallOrInvoke,
97 IsMustTail: CE && CE == MustTailCall,
98 Loc: CE ? CE->getExprLoc() : SourceLocation());
99}
100
101RValue CodeGenFunction::EmitCXXDestructorCall(
102 GlobalDecl Dtor, const CGCallee &Callee, llvm::Value *This, QualType ThisTy,
103 llvm::Value *ImplicitParam, QualType ImplicitParamTy, const CallExpr *CE,
104 llvm::CallBase **CallOrInvoke) {
105 const CXXMethodDecl *DtorDecl = cast<CXXMethodDecl>(Val: Dtor.getDecl());
106
107 assert(!ThisTy.isNull());
108 assert(ThisTy->getAsCXXRecordDecl() == DtorDecl->getParent() &&
109 "Pointer/Object mixup");
110
111 LangAS SrcAS = ThisTy.getAddressSpace();
112 LangAS DstAS = DtorDecl->getMethodQualifiers().getAddressSpace();
113 if (SrcAS != DstAS) {
114 QualType DstTy = DtorDecl->getThisType();
115 llvm::Type *NewType = CGM.getTypes().ConvertType(T: DstTy);
116 This = getTargetHooks().performAddrSpaceCast(CGF&: *this, V: This, SrcAddr: SrcAS, DestTy: NewType);
117 }
118
119 CallArgList Args;
120 commonEmitCXXMemberOrOperatorCall(CGF&: *this, GD: Dtor, This, ImplicitParam,
121 ImplicitParamTy, CE, Args, RtlArgs: nullptr);
122 return EmitCall(CallInfo: CGM.getTypes().arrangeCXXStructorDeclaration(GD: Dtor), Callee,
123 ReturnValue: ReturnValueSlot(), Args, CallOrInvoke,
124 IsMustTail: CE && CE == MustTailCall,
125 Loc: CE ? CE->getExprLoc() : SourceLocation{});
126}
127
128RValue
129CodeGenFunction::EmitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) {
130 QualType DestroyedType = E->getDestroyedType();
131 if (DestroyedType.hasStrongOrWeakObjCLifetime()) {
132 // Automatic Reference Counting:
133 // If the pseudo-expression names a retainable object with weak or
134 // strong lifetime, the object shall be released.
135 Expr *BaseExpr = E->getBase();
136 Address BaseValue = Address::invalid();
137 Qualifiers BaseQuals;
138
139 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
140 if (E->isArrow()) {
141 BaseValue = EmitPointerWithAlignment(Addr: BaseExpr);
142 const auto *PTy = BaseExpr->getType()->castAs<PointerType>();
143 BaseQuals = PTy->getPointeeType().getQualifiers();
144 } else {
145 LValue BaseLV = EmitLValue(E: BaseExpr);
146 BaseValue = BaseLV.getAddress();
147 QualType BaseTy = BaseExpr->getType();
148 BaseQuals = BaseTy.getQualifiers();
149 }
150
151 switch (DestroyedType.getObjCLifetime()) {
152 case Qualifiers::OCL_None:
153 case Qualifiers::OCL_ExplicitNone:
154 case Qualifiers::OCL_Autoreleasing:
155 break;
156
157 case Qualifiers::OCL_Strong:
158 EmitARCRelease(
159 value: Builder.CreateLoad(Addr: BaseValue, IsVolatile: DestroyedType.isVolatileQualified()),
160 precise: ARCPreciseLifetime);
161 break;
162
163 case Qualifiers::OCL_Weak:
164 EmitARCDestroyWeak(addr: BaseValue);
165 break;
166 }
167 } else {
168 // C++ [expr.pseudo]p1:
169 // The result shall only be used as the operand for the function call
170 // operator (), and the result of such a call has type void. The only
171 // effect is the evaluation of the postfix-expression before the dot or
172 // arrow.
173 EmitIgnoredExpr(E: E->getBase());
174 }
175
176 return RValue::get(V: nullptr);
177}
178
179static CXXRecordDecl *getCXXRecord(const Expr *E) {
180 QualType T = E->getType();
181 if (const PointerType *PTy = T->getAs<PointerType>())
182 T = PTy->getPointeeType();
183 return T->castAsCXXRecordDecl();
184}
185
186// Note: This function also emit constructor calls to support a MSVC
187// extensions allowing explicit constructor function call.
188RValue CodeGenFunction::EmitCXXMemberCallExpr(const CXXMemberCallExpr *CE,
189 ReturnValueSlot ReturnValue,
190 llvm::CallBase **CallOrInvoke) {
191 const Expr *callee = CE->getCallee()->IgnoreParens();
192
193 if (isa<BinaryOperator>(Val: callee))
194 return EmitCXXMemberPointerCallExpr(E: CE, ReturnValue, CallOrInvoke);
195
196 const MemberExpr *ME = cast<MemberExpr>(Val: callee);
197 const CXXMethodDecl *MD = cast<CXXMethodDecl>(Val: ME->getMemberDecl());
198
199 if (MD->isStatic()) {
200 // The method is static, emit it as we would a regular call.
201 CGCallee callee =
202 CGCallee::forDirect(functionPtr: CGM.GetAddrOfFunction(GD: MD), abstractInfo: GlobalDecl(MD));
203 return EmitCall(FnType: getContext().getPointerType(T: MD->getType()), Callee: callee, E: CE,
204 ReturnValue, /*Chain=*/nullptr, CallOrInvoke);
205 }
206
207 bool HasQualifier = ME->hasQualifier();
208 NestedNameSpecifier Qualifier = ME->getQualifier();
209 bool IsArrow = ME->isArrow();
210 const Expr *Base = ME->getBase();
211
212 return EmitCXXMemberOrOperatorMemberCallExpr(CE, MD, ReturnValue,
213 HasQualifier, Qualifier, IsArrow,
214 Base, CallOrInvoke);
215}
216
217RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
218 const CallExpr *CE, const CXXMethodDecl *MD, ReturnValueSlot ReturnValue,
219 bool HasQualifier, NestedNameSpecifier Qualifier, bool IsArrow,
220 const Expr *Base, llvm::CallBase **CallOrInvoke) {
221 assert(isa<CXXMemberCallExpr>(CE) || isa<CXXOperatorCallExpr>(CE));
222
223 // Compute the object pointer.
224 bool CanUseVirtualCall = MD->isVirtual() && !HasQualifier;
225
226 const CXXMethodDecl *DevirtualizedMethod = nullptr;
227 if (CanUseVirtualCall &&
228 MD->getDevirtualizedMethod(Base, IsAppleKext: getLangOpts().AppleKext)) {
229 const CXXRecordDecl *BestDynamicDecl = Base->getBestDynamicClassType();
230 DevirtualizedMethod = MD->getCorrespondingMethodInClass(RD: BestDynamicDecl);
231 assert(DevirtualizedMethod);
232 const CXXRecordDecl *DevirtualizedClass = DevirtualizedMethod->getParent();
233 const Expr *Inner = Base->IgnoreParenBaseCasts();
234 if (DevirtualizedMethod->getReturnType().getCanonicalType() !=
235 MD->getReturnType().getCanonicalType())
236 // If the return types are not the same, this might be a case where more
237 // code needs to run to compensate for it. For example, the derived
238 // method might return a type that inherits form from the return
239 // type of MD and has a prefix.
240 // For now we just avoid devirtualizing these covariant cases.
241 DevirtualizedMethod = nullptr;
242 else if (getCXXRecord(E: Inner) == DevirtualizedClass)
243 // If the class of the Inner expression is where the dynamic method
244 // is defined, build the this pointer from it.
245 Base = Inner;
246 else if (getCXXRecord(E: Base) != DevirtualizedClass) {
247 // If the method is defined in a class that is not the best dynamic
248 // one or the one of the full expression, we would have to build
249 // a derived-to-base cast to compute the correct this pointer, but
250 // we don't have support for that yet, so do a virtual call.
251 DevirtualizedMethod = nullptr;
252 }
253 }
254
255 bool TrivialForCodegen =
256 MD->isTrivial() || (MD->isDefaulted() && MD->getParent()->isUnion());
257 bool TrivialAssignment =
258 TrivialForCodegen &&
259 (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator()) &&
260 !MD->getParent()->mayInsertExtraPadding();
261
262 // C++17 demands that we evaluate the RHS of a (possibly-compound) assignment
263 // operator before the LHS.
264 CallArgList RtlArgStorage;
265 CallArgList *RtlArgs = nullptr;
266 LValue TrivialAssignmentRHS;
267 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(Val: CE)) {
268 if (OCE->isAssignmentOp()) {
269 if (TrivialAssignment) {
270 TrivialAssignmentRHS = EmitLValue(E: CE->getArg(Arg: 1));
271 } else {
272 RtlArgs = &RtlArgStorage;
273 EmitCallArgs(Args&: *RtlArgs, Prototype: MD->getType()->castAs<FunctionProtoType>(),
274 ArgRange: drop_begin(RangeOrContainer: CE->arguments(), N: 1), AC: CE->getDirectCallee(),
275 /*ParamsToSkip*/ 0, Order: EvaluationOrder::ForceRightToLeft);
276 }
277 }
278 }
279
280 LValue This;
281 if (IsArrow) {
282 LValueBaseInfo BaseInfo;
283 TBAAAccessInfo TBAAInfo;
284 Address ThisValue = EmitPointerWithAlignment(Addr: Base, BaseInfo: &BaseInfo, TBAAInfo: &TBAAInfo);
285 This = MakeAddrLValue(Addr: ThisValue, T: Base->getType()->getPointeeType(),
286 BaseInfo, TBAAInfo);
287 } else {
288 This = EmitLValue(E: Base);
289 }
290
291 if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Val: MD)) {
292 // This is the MSVC p->Ctor::Ctor(...) extension. We assume that's
293 // constructing a new complete object of type Ctor.
294 assert(!RtlArgs);
295 assert(ReturnValue.isNull() && "Constructor shouldn't have return value");
296 CallArgList Args;
297 commonEmitCXXMemberOrOperatorCall(
298 CGF&: *this, GD: {Ctor, Ctor_Complete}, This: This.getPointer(CGF&: *this),
299 /*ImplicitParam=*/nullptr,
300 /*ImplicitParamTy=*/QualType(), CE, Args, RtlArgs: nullptr);
301
302 EmitCXXConstructorCall(D: Ctor, Type: Ctor_Complete, /*ForVirtualBase=*/false,
303 /*Delegating=*/false, This: This.getAddress(), Args,
304 Overlap: AggValueSlot::DoesNotOverlap, Loc: CE->getExprLoc(),
305 /*NewPointerIsChecked=*/false, CallOrInvoke);
306 return RValue::get(V: nullptr);
307 }
308
309 if (TrivialForCodegen) {
310 if (isa<CXXDestructorDecl>(Val: MD))
311 return RValue::get(V: nullptr);
312
313 if (TrivialAssignment) {
314 // We don't like to generate the trivial copy/move assignment operator
315 // when it isn't necessary; just produce the proper effect here.
316 // It's important that we use the result of EmitLValue here rather than
317 // emitting call arguments, in order to preserve TBAA information from
318 // the RHS.
319 LValue RHS = isa<CXXOperatorCallExpr>(Val: CE) ? TrivialAssignmentRHS
320 : EmitLValue(E: *CE->arg_begin());
321 EmitAggregateAssign(Dest: This, Src: RHS, EltTy: CE->getType());
322 return RValue::get(V: This.getPointer(CGF&: *this));
323 }
324
325 assert(MD->getParent()->mayInsertExtraPadding() &&
326 "unknown trivial member function");
327 }
328
329 // Compute the function type we're calling.
330 const CXXMethodDecl *CalleeDecl =
331 DevirtualizedMethod ? DevirtualizedMethod : MD;
332 const CGFunctionInfo *FInfo = nullptr;
333 if (const auto *Dtor = dyn_cast<CXXDestructorDecl>(Val: CalleeDecl))
334 FInfo = &CGM.getTypes().arrangeCXXStructorDeclaration(
335 GD: GlobalDecl(Dtor, Dtor_Complete));
336 else
337 FInfo = &CGM.getTypes().arrangeCXXMethodDeclaration(MD: CalleeDecl);
338
339 llvm::FunctionType *Ty = CGM.getTypes().GetFunctionType(Info: *FInfo);
340
341 // C++11 [class.mfct.non-static]p2:
342 // If a non-static member function of a class X is called for an object that
343 // is not of type X, or of a type derived from X, the behavior is undefined.
344 SourceLocation CallLoc;
345 ASTContext &C = getContext();
346 if (CE)
347 CallLoc = CE->getExprLoc();
348
349 SanitizerSet SkippedChecks;
350 if (const auto *CMCE = dyn_cast<CXXMemberCallExpr>(Val: CE)) {
351 auto *IOA = CMCE->getImplicitObjectArgument();
352 bool IsImplicitObjectCXXThis = IsWrappedCXXThis(E: IOA);
353 if (IsImplicitObjectCXXThis)
354 SkippedChecks.set(K: SanitizerKind::Alignment, Value: true);
355 if (IsImplicitObjectCXXThis || isa<DeclRefExpr>(Val: IOA))
356 SkippedChecks.set(K: SanitizerKind::Null, Value: true);
357 }
358
359 if (sanitizePerformTypeCheck())
360 EmitTypeCheck(TCK: CodeGenFunction::TCK_MemberCall, Loc: CallLoc,
361 V: This.emitRawPointer(CGF&: *this),
362 Type: C.getCanonicalTagType(TD: CalleeDecl->getParent()),
363 /*Alignment=*/CharUnits::Zero(), SkippedChecks);
364
365 // C++ [class.virtual]p12:
366 // Explicit qualification with the scope operator (5.1) suppresses the
367 // virtual call mechanism.
368 //
369 // We also don't emit a virtual call if the base expression has a record type
370 // because then we know what the type is.
371 bool UseVirtualCall = CanUseVirtualCall && !DevirtualizedMethod;
372
373 if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(Val: CalleeDecl)) {
374 assert(CE->arguments().empty() &&
375 "Destructor shouldn't have explicit parameters");
376 assert(ReturnValue.isNull() && "Destructor shouldn't have return value");
377 if (UseVirtualCall) {
378 CGM.getCXXABI().EmitVirtualDestructorCall(
379 CGF&: *this, Dtor, DtorType: Dtor_Complete, This: This.getAddress(),
380 E: cast<CXXMemberCallExpr>(Val: CE), CallOrInvoke);
381 } else {
382 GlobalDecl GD(Dtor, Dtor_Complete);
383 CGCallee Callee;
384 if (getLangOpts().AppleKext && Dtor->isVirtual() && HasQualifier)
385 Callee = BuildAppleKextVirtualCall(MD: Dtor, Qual: Qualifier, Ty);
386 else if (!DevirtualizedMethod)
387 Callee =
388 CGCallee::forDirect(functionPtr: CGM.getAddrOfCXXStructor(GD, FnInfo: FInfo, FnType: Ty), abstractInfo: GD);
389 else {
390 Callee = CGCallee::forDirect(functionPtr: CGM.GetAddrOfFunction(GD, Ty), abstractInfo: GD);
391 }
392
393 QualType ThisTy =
394 IsArrow ? Base->getType()->getPointeeType() : Base->getType();
395 EmitCXXDestructorCall(Dtor: GD, Callee, This: This.getPointer(CGF&: *this), ThisTy,
396 /*ImplicitParam=*/nullptr,
397 /*ImplicitParamTy=*/QualType(), CE, CallOrInvoke);
398 }
399 return RValue::get(V: nullptr);
400 }
401
402 // FIXME: Uses of 'MD' past this point need to be audited. We may need to use
403 // 'CalleeDecl' instead.
404
405 CGCallee Callee;
406 if (UseVirtualCall) {
407 Callee = CGCallee::forVirtual(CE, MD, Addr: This.getAddress(), FTy: Ty);
408 } else {
409 if (SanOpts.has(K: SanitizerKind::CFINVCall) &&
410 MD->getParent()->isDynamicClass()) {
411 llvm::Value *VTable;
412 const CXXRecordDecl *RD;
413 std::tie(args&: VTable, args&: RD) = CGM.getCXXABI().LoadVTablePtr(
414 CGF&: *this, This: This.getAddress(), RD: CalleeDecl->getParent());
415 EmitVTablePtrCheckForCall(RD, VTable, TCK: CFITCK_NVCall, Loc: CE->getBeginLoc());
416 }
417
418 if (getLangOpts().AppleKext && MD->isVirtual() && HasQualifier)
419 Callee = BuildAppleKextVirtualCall(MD, Qual: Qualifier, Ty);
420 else if (!DevirtualizedMethod)
421 Callee =
422 CGCallee::forDirect(functionPtr: CGM.GetAddrOfFunction(GD: MD, Ty), abstractInfo: GlobalDecl(MD));
423 else {
424 Callee =
425 CGCallee::forDirect(functionPtr: CGM.GetAddrOfFunction(GD: DevirtualizedMethod, Ty),
426 abstractInfo: GlobalDecl(DevirtualizedMethod));
427 }
428 }
429
430 if (MD->isVirtual()) {
431 Address NewThisAddr =
432 CGM.getCXXABI().adjustThisArgumentForVirtualFunctionCall(
433 CGF&: *this, GD: CalleeDecl, This: This.getAddress(), VirtualCall: UseVirtualCall);
434 This.setAddress(NewThisAddr);
435 }
436
437 return EmitCXXMemberOrOperatorCall(
438 MD: CalleeDecl, Callee, ReturnValue, This: This.getPointer(CGF&: *this),
439 /*ImplicitParam=*/nullptr, ImplicitParamTy: QualType(), CE, RtlArgs, CallOrInvoke);
440}
441
442RValue
443CodeGenFunction::EmitCXXMemberPointerCallExpr(const CXXMemberCallExpr *E,
444 ReturnValueSlot ReturnValue,
445 llvm::CallBase **CallOrInvoke) {
446 const BinaryOperator *BO =
447 cast<BinaryOperator>(Val: E->getCallee()->IgnoreParens());
448 const Expr *BaseExpr = BO->getLHS();
449 const Expr *MemFnExpr = BO->getRHS();
450
451 const auto *MPT = MemFnExpr->getType()->castAs<MemberPointerType>();
452 const auto *FPT = MPT->getPointeeType()->castAs<FunctionProtoType>();
453 const auto *RD = MPT->getMostRecentCXXRecordDecl();
454
455 // Emit the 'this' pointer.
456 Address This = Address::invalid();
457 if (BO->getOpcode() == BO_PtrMemI)
458 This = EmitPointerWithAlignment(Addr: BaseExpr, BaseInfo: nullptr, TBAAInfo: nullptr, IsKnownNonNull: KnownNonNull);
459 else
460 This = EmitLValue(E: BaseExpr, IsKnownNonNull: KnownNonNull).getAddress();
461
462 CanQualType ClassType = CGM.getContext().getCanonicalTagType(TD: RD);
463 EmitTypeCheck(TCK: TCK_MemberCall, Loc: E->getExprLoc(), V: This.emitRawPointer(CGF&: *this),
464 Type: ClassType);
465
466 // Get the member function pointer.
467 llvm::Value *MemFnPtr = EmitScalarExpr(E: MemFnExpr);
468
469 // Ask the ABI to load the callee. Note that This is modified.
470 llvm::Value *ThisPtrForCall = nullptr;
471 CGCallee Callee = CGM.getCXXABI().EmitLoadOfMemberFunctionPointer(
472 CGF&: *this, E: BO, This, ThisPtrForCall, MemPtr: MemFnPtr, MPT);
473
474 CallArgList Args;
475
476 QualType ThisType = getContext().getPointerType(T: ClassType);
477
478 // Push the this ptr.
479 Args.add(rvalue: RValue::get(V: ThisPtrForCall), type: ThisType);
480
481 RequiredArgs required = RequiredArgs::forPrototypePlus(prototype: FPT, additional: 1);
482
483 // And the rest of the call args
484 EmitCallArgs(Args, Prototype: FPT, ArgRange: E->arguments());
485 return EmitCall(CallInfo: CGM.getTypes().arrangeCXXMethodCall(args: Args, type: FPT, required,
486 /*PrefixSize=*/numPrefixArgs: 0),
487 Callee, ReturnValue, Args, CallOrInvoke, IsMustTail: E == MustTailCall,
488 Loc: E->getExprLoc());
489}
490
491RValue CodeGenFunction::EmitCXXOperatorMemberCallExpr(
492 const CXXOperatorCallExpr *E, const CXXMethodDecl *MD,
493 ReturnValueSlot ReturnValue, llvm::CallBase **CallOrInvoke) {
494 assert(MD->isImplicitObjectMemberFunction() &&
495 "Trying to emit a member call expr on a static method!");
496 return EmitCXXMemberOrOperatorMemberCallExpr(
497 CE: E, MD, ReturnValue, /*HasQualifier=*/false, /*Qualifier=*/std::nullopt,
498 /*IsArrow=*/false, Base: E->getArg(Arg: 0), CallOrInvoke);
499}
500
501RValue CodeGenFunction::EmitCUDAKernelCallExpr(const CUDAKernelCallExpr *E,
502 ReturnValueSlot ReturnValue,
503 llvm::CallBase **CallOrInvoke) {
504 // Emit as a device kernel call if CUDA device code is to be generated.
505 // TODO: implement for HIP
506 if (!getLangOpts().HIP && getLangOpts().CUDAIsDevice)
507 return CGM.getCUDARuntime().EmitCUDADeviceKernelCallExpr(
508 CGF&: *this, E, ReturnValue, CallOrInvoke);
509 return CGM.getCUDARuntime().EmitCUDAKernelCallExpr(CGF&: *this, E, ReturnValue,
510 CallOrInvoke);
511}
512
513static void EmitNullBaseClassInitialization(CodeGenFunction &CGF,
514 Address DestPtr,
515 const CXXRecordDecl *Base) {
516 if (Base->isEmpty())
517 return;
518
519 DestPtr = DestPtr.withElementType(ElemTy: CGF.Int8Ty);
520
521 const ASTRecordLayout &Layout = CGF.getContext().getASTRecordLayout(D: Base);
522 CharUnits NVSize = Layout.getNonVirtualSize();
523
524 // We cannot simply zero-initialize the entire base sub-object if vbptrs are
525 // present, they are initialized by the most derived class before calling the
526 // constructor.
527 SmallVector<std::pair<CharUnits, CharUnits>, 1> Stores;
528 Stores.emplace_back(Args: CharUnits::Zero(), Args&: NVSize);
529
530 // Each store is split by the existence of a vbptr.
531 CharUnits VBPtrWidth = CGF.getPointerSize();
532 std::vector<CharUnits> VBPtrOffsets =
533 CGF.CGM.getCXXABI().getVBPtrOffsets(RD: Base);
534 for (CharUnits VBPtrOffset : VBPtrOffsets) {
535 // Stop before we hit any virtual base pointers located in virtual bases.
536 if (VBPtrOffset >= NVSize)
537 break;
538 std::pair<CharUnits, CharUnits> LastStore = Stores.pop_back_val();
539 CharUnits LastStoreOffset = LastStore.first;
540 CharUnits LastStoreSize = LastStore.second;
541
542 CharUnits SplitBeforeOffset = LastStoreOffset;
543 CharUnits SplitBeforeSize = VBPtrOffset - SplitBeforeOffset;
544 assert(!SplitBeforeSize.isNegative() && "negative store size!");
545 if (!SplitBeforeSize.isZero())
546 Stores.emplace_back(Args&: SplitBeforeOffset, Args&: SplitBeforeSize);
547
548 CharUnits SplitAfterOffset = VBPtrOffset + VBPtrWidth;
549 CharUnits SplitAfterSize = LastStoreSize - SplitAfterOffset;
550 assert(!SplitAfterSize.isNegative() && "negative store size!");
551 if (!SplitAfterSize.isZero())
552 Stores.emplace_back(Args&: SplitAfterOffset, Args&: SplitAfterSize);
553 }
554
555 // If the type contains a pointer to data member we can't memset it to zero.
556 // Instead, create a null constant and copy it to the destination.
557 // TODO: there are other patterns besides zero that we can usefully memset,
558 // like -1, which happens to be the pattern used by member-pointers.
559 // TODO: isZeroInitializable can be over-conservative in the case where a
560 // virtual base contains a member pointer.
561 llvm::Constant *NullConstantForBase = CGF.CGM.EmitNullConstantForBase(Record: Base);
562 if (!NullConstantForBase->isNullValue()) {
563 llvm::GlobalVariable *NullVariable = new llvm::GlobalVariable(
564 CGF.CGM.getModule(), NullConstantForBase->getType(),
565 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage,
566 NullConstantForBase, Twine());
567
568 CharUnits Align =
569 std::max(a: Layout.getNonVirtualAlignment(), b: DestPtr.getAlignment());
570 NullVariable->setAlignment(Align.getAsAlign());
571
572 Address SrcPtr(NullVariable, CGF.Int8Ty, Align);
573
574 // Get and call the appropriate llvm.memcpy overload.
575 for (std::pair<CharUnits, CharUnits> Store : Stores) {
576 CharUnits StoreOffset = Store.first;
577 CharUnits StoreSize = Store.second;
578 llvm::Value *StoreSizeVal = CGF.CGM.getSize(numChars: StoreSize);
579 CGF.Builder.CreateMemCpy(
580 Dest: CGF.Builder.CreateConstInBoundsByteGEP(Addr: DestPtr, Offset: StoreOffset),
581 Src: CGF.Builder.CreateConstInBoundsByteGEP(Addr: SrcPtr, Offset: StoreOffset),
582 Size: StoreSizeVal);
583 }
584
585 // Otherwise, just memset the whole thing to zero. This is legal
586 // because in LLVM, all default initializers (other than the ones we just
587 // handled above) are guaranteed to have a bit pattern of all zeros.
588 } else {
589 for (std::pair<CharUnits, CharUnits> Store : Stores) {
590 CharUnits StoreOffset = Store.first;
591 CharUnits StoreSize = Store.second;
592 llvm::Value *StoreSizeVal = CGF.CGM.getSize(numChars: StoreSize);
593 CGF.Builder.CreateMemSet(
594 Dest: CGF.Builder.CreateConstInBoundsByteGEP(Addr: DestPtr, Offset: StoreOffset),
595 Value: CGF.Builder.getInt8(C: 0), Size: StoreSizeVal);
596 }
597 }
598}
599
600void CodeGenFunction::EmitCXXConstructExpr(const CXXConstructExpr *E,
601 AggValueSlot Dest) {
602 assert(!Dest.isIgnored() && "Must have a destination!");
603 const CXXConstructorDecl *CD = E->getConstructor();
604
605 // If we require zero initialization before (or instead of) calling the
606 // constructor, as can be the case with a non-user-provided default
607 // constructor, emit the zero initialization now, unless destination is
608 // already zeroed.
609 if (E->requiresZeroInitialization() && !Dest.isZeroed()) {
610 switch (E->getConstructionKind()) {
611 case CXXConstructionKind::Delegating:
612 case CXXConstructionKind::Complete:
613 EmitNullInitialization(DestPtr: Dest.getAddress(), Ty: E->getType());
614 break;
615 case CXXConstructionKind::VirtualBase:
616 case CXXConstructionKind::NonVirtualBase:
617 EmitNullBaseClassInitialization(CGF&: *this, DestPtr: Dest.getAddress(),
618 Base: CD->getParent());
619 break;
620 }
621 }
622
623 // If this is a call to a trivial default constructor, do nothing.
624 if (CD->isTrivial() && CD->isDefaultConstructor())
625 return;
626
627 // Elide the constructor if we're constructing from a temporary.
628 if (getLangOpts().ElideConstructors && E->isElidable()) {
629 // FIXME: This only handles the simplest case, where the source object
630 // is passed directly as the first argument to the constructor.
631 // This should also handle stepping though implicit casts and
632 // conversion sequences which involve two steps, with a
633 // conversion operator followed by a converting constructor.
634 const Expr *SrcObj = E->getArg(Arg: 0);
635 assert(SrcObj->isTemporaryObject(getContext(), CD->getParent()));
636 assert(
637 getContext().hasSameUnqualifiedType(E->getType(), SrcObj->getType()));
638 EmitAggExpr(E: SrcObj, AS: Dest);
639 return;
640 }
641
642 if (const ArrayType *arrayType = getContext().getAsArrayType(T: E->getType())) {
643 EmitCXXAggrConstructorCall(D: CD, ArrayTy: arrayType, ArrayPtr: Dest.getAddress(), E,
644 NewPointerIsChecked: Dest.isSanitizerChecked());
645 } else {
646 CXXCtorType Type = Ctor_Complete;
647 bool ForVirtualBase = false;
648 bool Delegating = false;
649
650 switch (E->getConstructionKind()) {
651 case CXXConstructionKind::Delegating:
652 // We should be emitting a constructor; GlobalDecl will assert this
653 Type = CurGD.getCtorType();
654 Delegating = true;
655 break;
656
657 case CXXConstructionKind::Complete:
658 Type = Ctor_Complete;
659 break;
660
661 case CXXConstructionKind::VirtualBase:
662 ForVirtualBase = true;
663 [[fallthrough]];
664
665 case CXXConstructionKind::NonVirtualBase:
666 Type = Ctor_Base;
667 }
668
669 // Call the constructor.
670 EmitCXXConstructorCall(D: CD, Type, ForVirtualBase, Delegating, ThisAVS: Dest, E);
671 }
672}
673
674void CodeGenFunction::EmitSynthesizedCXXCopyCtor(Address Dest, Address Src,
675 const Expr *Exp) {
676 if (const ExprWithCleanups *E = dyn_cast<ExprWithCleanups>(Val: Exp))
677 Exp = E->getSubExpr();
678 assert(isa<CXXConstructExpr>(Exp) &&
679 "EmitSynthesizedCXXCopyCtor - unknown copy ctor expr");
680 const CXXConstructExpr *E = cast<CXXConstructExpr>(Val: Exp);
681 const CXXConstructorDecl *CD = E->getConstructor();
682 RunCleanupsScope Scope(*this);
683
684 // If we require zero initialization before (or instead of) calling the
685 // constructor, as can be the case with a non-user-provided default
686 // constructor, emit the zero initialization now.
687 // FIXME. Do I still need this for a copy ctor synthesis?
688 if (E->requiresZeroInitialization())
689 EmitNullInitialization(DestPtr: Dest, Ty: E->getType());
690
691 assert(!getContext().getAsConstantArrayType(E->getType()) &&
692 "EmitSynthesizedCXXCopyCtor - Copied-in Array");
693 EmitSynthesizedCXXCopyCtorCall(D: CD, This: Dest, Src, E);
694}
695
696static CharUnits CalculateCookiePadding(CodeGenFunction &CGF,
697 const CXXNewExpr *E) {
698 if (!E->isArray())
699 return CharUnits::Zero();
700
701 // No cookie is required if the operator new[] being used is the
702 // reserved placement operator new[].
703 if (E->getOperatorNew()->isReservedGlobalPlacementOperator())
704 return CharUnits::Zero();
705
706 return CGF.CGM.getCXXABI().GetArrayCookieSize(expr: E);
707}
708
709static llvm::Value *EmitCXXNewAllocSize(CodeGenFunction &CGF,
710 const CXXNewExpr *e,
711 unsigned minElements,
712 llvm::Value *&numElements,
713 llvm::Value *&sizeWithoutCookie) {
714 QualType type = e->getAllocatedType();
715
716 if (!e->isArray()) {
717 CharUnits typeSize = CGF.getContext().getTypeSizeInChars(T: type);
718 sizeWithoutCookie =
719 llvm::ConstantInt::get(Ty: CGF.SizeTy, V: typeSize.getQuantity());
720 return sizeWithoutCookie;
721 }
722
723 // The width of size_t.
724 unsigned sizeWidth = CGF.SizeTy->getBitWidth();
725
726 // Figure out the cookie size.
727 llvm::APInt cookieSize(sizeWidth,
728 CalculateCookiePadding(CGF, E: e).getQuantity());
729
730 // Emit the array size expression.
731 // We multiply the size of all dimensions for NumElements.
732 // e.g for 'int[2][3]', ElemType is 'int' and NumElements is 6.
733 numElements = ConstantEmitter(CGF).tryEmitAbstract(
734 E: *e->getArraySize(), T: (*e->getArraySize())->getType());
735 if (!numElements)
736 numElements = CGF.EmitScalarExpr(E: *e->getArraySize());
737 assert(isa<llvm::IntegerType>(numElements->getType()));
738
739 // The number of elements can be have an arbitrary integer type;
740 // essentially, we need to multiply it by a constant factor, add a
741 // cookie size, and verify that the result is representable as a
742 // size_t. That's just a gloss, though, and it's wrong in one
743 // important way: if the count is negative, it's an error even if
744 // the cookie size would bring the total size >= 0.
745 bool isSigned =
746 (*e->getArraySize())->getType()->isSignedIntegerOrEnumerationType();
747 llvm::IntegerType *numElementsType =
748 cast<llvm::IntegerType>(Val: numElements->getType());
749 unsigned numElementsWidth = numElementsType->getBitWidth();
750
751 // Compute the constant factor.
752 llvm::APInt arraySizeMultiplier(sizeWidth, 1);
753 while (const ConstantArrayType *CAT =
754 CGF.getContext().getAsConstantArrayType(T: type)) {
755 type = CAT->getElementType();
756 arraySizeMultiplier *= CAT->getSize();
757 }
758
759 CharUnits typeSize = CGF.getContext().getTypeSizeInChars(T: type);
760 llvm::APInt typeSizeMultiplier(sizeWidth, typeSize.getQuantity());
761 typeSizeMultiplier *= arraySizeMultiplier;
762
763 // This will be a size_t.
764 llvm::Value *size;
765
766 // If someone is doing 'new int[42]' there is no need to do a dynamic check.
767 // Don't bloat the -O0 code.
768 if (llvm::ConstantInt *numElementsC =
769 dyn_cast<llvm::ConstantInt>(Val: numElements)) {
770 const llvm::APInt &count = numElementsC->getValue();
771
772 bool hasAnyOverflow = false;
773
774 // If 'count' was a negative number, it's an overflow.
775 if (isSigned && count.isNegative())
776 hasAnyOverflow = true;
777
778 // We want to do all this arithmetic in size_t. If numElements is
779 // wider than that, check whether it's already too big, and if so,
780 // overflow.
781 else if (numElementsWidth > sizeWidth &&
782 numElementsWidth - sizeWidth > count.countl_zero())
783 hasAnyOverflow = true;
784
785 // Okay, compute a count at the right width.
786 llvm::APInt adjustedCount = count.zextOrTrunc(width: sizeWidth);
787
788 // If there is a brace-initializer, we cannot allocate fewer elements than
789 // there are initializers. If we do, that's treated like an overflow.
790 if (adjustedCount.ult(RHS: minElements))
791 hasAnyOverflow = true;
792
793 // Scale numElements by that. This might overflow, but we don't
794 // care because it only overflows if allocationSize does, too, and
795 // if that overflows then we shouldn't use this.
796 numElements =
797 llvm::ConstantInt::get(Ty: CGF.SizeTy, V: adjustedCount * arraySizeMultiplier);
798
799 // Compute the size before cookie, and track whether it overflowed.
800 bool overflow;
801 llvm::APInt allocationSize =
802 adjustedCount.umul_ov(RHS: typeSizeMultiplier, Overflow&: overflow);
803 hasAnyOverflow |= overflow;
804
805 // Add in the cookie, and check whether it's overflowed.
806 if (cookieSize != 0) {
807 // Save the current size without a cookie. This shouldn't be
808 // used if there was overflow.
809 sizeWithoutCookie = llvm::ConstantInt::get(Ty: CGF.SizeTy, V: allocationSize);
810
811 allocationSize = allocationSize.uadd_ov(RHS: cookieSize, Overflow&: overflow);
812 hasAnyOverflow |= overflow;
813 }
814
815 // On overflow, produce a -1 so operator new will fail.
816 if (hasAnyOverflow) {
817 size = llvm::Constant::getAllOnesValue(Ty: CGF.SizeTy);
818 } else {
819 size = llvm::ConstantInt::get(Ty: CGF.SizeTy, V: allocationSize);
820 }
821
822 // Otherwise, we might need to use the overflow intrinsics.
823 } else {
824 // There are up to five conditions we need to test for:
825 // 1) if isSigned, we need to check whether numElements is negative;
826 // 2) if numElementsWidth > sizeWidth, we need to check whether
827 // numElements is larger than something representable in size_t;
828 // 3) if minElements > 0, we need to check whether numElements is smaller
829 // than that.
830 // 4) we need to compute
831 // sizeWithoutCookie := numElements * typeSizeMultiplier
832 // and check whether it overflows; and
833 // 5) if we need a cookie, we need to compute
834 // size := sizeWithoutCookie + cookieSize
835 // and check whether it overflows.
836
837 llvm::Value *hasOverflow = nullptr;
838
839 // If numElementsWidth > sizeWidth, then one way or another, we're
840 // going to have to do a comparison for (2), and this happens to
841 // take care of (1), too.
842 if (numElementsWidth > sizeWidth) {
843 llvm::APInt threshold =
844 llvm::APInt::getOneBitSet(numBits: numElementsWidth, BitNo: sizeWidth);
845
846 llvm::Value *thresholdV =
847 llvm::ConstantInt::get(Ty: numElementsType, V: threshold);
848
849 hasOverflow = CGF.Builder.CreateICmpUGE(LHS: numElements, RHS: thresholdV);
850 numElements = CGF.Builder.CreateTrunc(V: numElements, DestTy: CGF.SizeTy);
851
852 // Otherwise, if we're signed, we want to sext up to size_t.
853 } else if (isSigned) {
854 if (numElementsWidth < sizeWidth)
855 numElements = CGF.Builder.CreateSExt(V: numElements, DestTy: CGF.SizeTy);
856
857 // If there's a non-1 type size multiplier, then we can do the
858 // signedness check at the same time as we do the multiply
859 // because a negative number times anything will cause an
860 // unsigned overflow. Otherwise, we have to do it here. But at least
861 // in this case, we can subsume the >= minElements check.
862 if (typeSizeMultiplier == 1)
863 hasOverflow = CGF.Builder.CreateICmpSLT(
864 LHS: numElements, RHS: llvm::ConstantInt::get(Ty: CGF.SizeTy, V: minElements));
865
866 // Otherwise, zext up to size_t if necessary.
867 } else if (numElementsWidth < sizeWidth) {
868 numElements = CGF.Builder.CreateZExt(V: numElements, DestTy: CGF.SizeTy);
869 }
870
871 assert(numElements->getType() == CGF.SizeTy);
872
873 if (minElements) {
874 // Don't allow allocation of fewer elements than we have initializers.
875 if (!hasOverflow) {
876 hasOverflow = CGF.Builder.CreateICmpULT(
877 LHS: numElements, RHS: llvm::ConstantInt::get(Ty: CGF.SizeTy, V: minElements));
878 } else if (numElementsWidth > sizeWidth) {
879 // The other existing overflow subsumes this check.
880 // We do an unsigned comparison, since any signed value < -1 is
881 // taken care of either above or below.
882 hasOverflow = CGF.Builder.CreateOr(
883 LHS: hasOverflow,
884 RHS: CGF.Builder.CreateICmpULT(
885 LHS: numElements, RHS: llvm::ConstantInt::get(Ty: CGF.SizeTy, V: minElements)));
886 }
887 }
888
889 size = numElements;
890
891 // Multiply by the type size if necessary. This multiplier
892 // includes all the factors for nested arrays.
893 //
894 // This step also causes numElements to be scaled up by the
895 // nested-array factor if necessary. Overflow on this computation
896 // can be ignored because the result shouldn't be used if
897 // allocation fails.
898 if (typeSizeMultiplier != 1) {
899 llvm::Function *umul_with_overflow =
900 CGF.CGM.getIntrinsic(IID: llvm::Intrinsic::umul_with_overflow, Tys: CGF.SizeTy);
901
902 llvm::Value *tsmV =
903 llvm::ConstantInt::get(Ty: CGF.SizeTy, V: typeSizeMultiplier);
904 llvm::Value *result =
905 CGF.Builder.CreateCall(Callee: umul_with_overflow, Args: {size, tsmV});
906
907 llvm::Value *overflowed = CGF.Builder.CreateExtractValue(Agg: result, Idxs: 1);
908 if (hasOverflow)
909 hasOverflow = CGF.Builder.CreateOr(LHS: hasOverflow, RHS: overflowed);
910 else
911 hasOverflow = overflowed;
912
913 size = CGF.Builder.CreateExtractValue(Agg: result, Idxs: 0);
914
915 // Also scale up numElements by the array size multiplier.
916 if (arraySizeMultiplier != 1) {
917 // If the base element type size is 1, then we can re-use the
918 // multiply we just did.
919 if (typeSize.isOne()) {
920 assert(arraySizeMultiplier == typeSizeMultiplier);
921 numElements = size;
922
923 // Otherwise we need a separate multiply.
924 } else {
925 llvm::Value *asmV =
926 llvm::ConstantInt::get(Ty: CGF.SizeTy, V: arraySizeMultiplier);
927 numElements = CGF.Builder.CreateMul(LHS: numElements, RHS: asmV);
928 }
929 }
930 } else {
931 // numElements doesn't need to be scaled.
932 assert(arraySizeMultiplier == 1);
933 }
934
935 // Add in the cookie size if necessary.
936 if (cookieSize != 0) {
937 sizeWithoutCookie = size;
938
939 llvm::Function *uadd_with_overflow =
940 CGF.CGM.getIntrinsic(IID: llvm::Intrinsic::uadd_with_overflow, Tys: CGF.SizeTy);
941
942 llvm::Value *cookieSizeV = llvm::ConstantInt::get(Ty: CGF.SizeTy, V: cookieSize);
943 llvm::Value *result =
944 CGF.Builder.CreateCall(Callee: uadd_with_overflow, Args: {size, cookieSizeV});
945
946 llvm::Value *overflowed = CGF.Builder.CreateExtractValue(Agg: result, Idxs: 1);
947 if (hasOverflow)
948 hasOverflow = CGF.Builder.CreateOr(LHS: hasOverflow, RHS: overflowed);
949 else
950 hasOverflow = overflowed;
951
952 size = CGF.Builder.CreateExtractValue(Agg: result, Idxs: 0);
953 }
954
955 // If we had any possibility of dynamic overflow, make a select to
956 // overwrite 'size' with an all-ones value, which should cause
957 // operator new to throw.
958 if (hasOverflow)
959 size = CGF.Builder.CreateSelect(
960 C: hasOverflow, True: llvm::Constant::getAllOnesValue(Ty: CGF.SizeTy), False: size);
961 }
962
963 if (cookieSize == 0)
964 sizeWithoutCookie = size;
965 else
966 assert(sizeWithoutCookie && "didn't set sizeWithoutCookie?");
967
968 return size;
969}
970
971static void StoreAnyExprIntoOneUnit(CodeGenFunction &CGF, const Expr *Init,
972 QualType AllocType, Address NewPtr,
973 AggValueSlot::Overlap_t MayOverlap) {
974 // FIXME: Refactor with EmitExprAsInit.
975 switch (CGF.getEvaluationKind(T: AllocType)) {
976 case TEK_Scalar:
977 CGF.EmitScalarInit(init: Init, D: nullptr, lvalue: CGF.MakeAddrLValue(Addr: NewPtr, T: AllocType),
978 capturedByInit: false);
979 return;
980 case TEK_Complex:
981 CGF.EmitComplexExprIntoLValue(E: Init, dest: CGF.MakeAddrLValue(Addr: NewPtr, T: AllocType),
982 /*isInit*/ true);
983 return;
984 case TEK_Aggregate: {
985 AggValueSlot Slot = AggValueSlot::forAddr(
986 addr: NewPtr, quals: AllocType.getQualifiers(), isDestructed: AggValueSlot::IsDestructed,
987 needsGC: AggValueSlot::DoesNotNeedGCBarriers, isAliased: AggValueSlot::IsNotAliased,
988 mayOverlap: MayOverlap, isZeroed: AggValueSlot::IsNotZeroed,
989 isChecked: AggValueSlot::IsSanitizerChecked);
990 CGF.EmitAggExpr(E: Init, AS: Slot);
991 return;
992 }
993 }
994 llvm_unreachable("bad evaluation kind");
995}
996
997void CodeGenFunction::EmitNewArrayInitializer(
998 const CXXNewExpr *E, QualType ElementType, llvm::Type *ElementTy,
999 Address BeginPtr, llvm::Value *NumElements,
1000 llvm::Value *AllocSizeWithoutCookie) {
1001 // If we have a type with trivial initialization and no initializer,
1002 // there's nothing to do.
1003 if (!E->hasInitializer())
1004 return;
1005
1006 Address CurPtr = BeginPtr;
1007
1008 unsigned InitListElements = 0;
1009
1010 const Expr *Init = E->getInitializer();
1011 Address EndOfInit = Address::invalid();
1012 QualType::DestructionKind DtorKind = ElementType.isDestructedType();
1013 CleanupDeactivationScope deactivation(*this);
1014 bool pushedCleanup = false;
1015
1016 CharUnits ElementSize = getContext().getTypeSizeInChars(T: ElementType);
1017 CharUnits ElementAlign =
1018 BeginPtr.getAlignment().alignmentOfArrayElement(elementSize: ElementSize);
1019
1020 // Attempt to perform zero-initialization using memset.
1021 auto TryMemsetInitialization = [&]() -> bool {
1022 // FIXME: If the type is a pointer-to-data-member under the Itanium ABI,
1023 // we can initialize with a memset to -1.
1024 if (!CGM.getTypes().isZeroInitializable(T: ElementType))
1025 return false;
1026
1027 // Optimization: since zero initialization will just set the memory
1028 // to all zeroes, generate a single memset to do it in one shot.
1029
1030 // Subtract out the size of any elements we've already initialized.
1031 auto *RemainingSize = AllocSizeWithoutCookie;
1032 if (InitListElements) {
1033 // We know this can't overflow; we check this when doing the allocation.
1034 auto *InitializedSize = llvm::ConstantInt::get(
1035 Ty: RemainingSize->getType(),
1036 V: getContext().getTypeSizeInChars(T: ElementType).getQuantity() *
1037 InitListElements);
1038 RemainingSize = Builder.CreateSub(LHS: RemainingSize, RHS: InitializedSize);
1039 }
1040
1041 // Create the memset.
1042 Builder.CreateMemSet(Dest: CurPtr, Value: Builder.getInt8(C: 0), Size: RemainingSize, IsVolatile: false);
1043 return true;
1044 };
1045
1046 const InitListExpr *ILE = dyn_cast<InitListExpr>(Val: Init);
1047 const CXXParenListInitExpr *CPLIE = nullptr;
1048 const StringLiteral *SL = nullptr;
1049 const ObjCEncodeExpr *OCEE = nullptr;
1050 const Expr *IgnoreParen = nullptr;
1051 if (!ILE) {
1052 IgnoreParen = Init->IgnoreParenImpCasts();
1053 CPLIE = dyn_cast<CXXParenListInitExpr>(Val: IgnoreParen);
1054 SL = dyn_cast<StringLiteral>(Val: IgnoreParen);
1055 OCEE = dyn_cast<ObjCEncodeExpr>(Val: IgnoreParen);
1056 }
1057
1058 // If the initializer is an initializer list, first do the explicit elements.
1059 if (ILE || CPLIE || SL || OCEE) {
1060 // Initializing from a (braced) string literal is a special case; the init
1061 // list element does not initialize a (single) array element.
1062 if ((ILE && ILE->isStringLiteralInit()) || SL || OCEE) {
1063 if (!ILE)
1064 Init = IgnoreParen;
1065 // Initialize the initial portion of length equal to that of the string
1066 // literal. The allocation must be for at least this much; we emitted a
1067 // check for that earlier.
1068 AggValueSlot Slot = AggValueSlot::forAddr(
1069 addr: CurPtr, quals: ElementType.getQualifiers(), isDestructed: AggValueSlot::IsDestructed,
1070 needsGC: AggValueSlot::DoesNotNeedGCBarriers, isAliased: AggValueSlot::IsNotAliased,
1071 mayOverlap: AggValueSlot::DoesNotOverlap, isZeroed: AggValueSlot::IsNotZeroed,
1072 isChecked: AggValueSlot::IsSanitizerChecked);
1073 EmitAggExpr(E: ILE ? ILE->getInit(Init: 0) : Init, AS: Slot);
1074
1075 // Move past these elements.
1076 InitListElements =
1077 cast<ConstantArrayType>(Val: Init->getType()->getAsArrayTypeUnsafe())
1078 ->getZExtSize();
1079 CurPtr = Builder.CreateConstInBoundsGEP(Addr: CurPtr, Index: InitListElements,
1080 Name: "string.init.end");
1081
1082 // Zero out the rest, if any remain.
1083 llvm::ConstantInt *ConstNum = dyn_cast<llvm::ConstantInt>(Val: NumElements);
1084 if (!ConstNum || !ConstNum->equalsInt(V: InitListElements)) {
1085 bool OK = TryMemsetInitialization();
1086 (void)OK;
1087 assert(OK && "couldn't memset character type?");
1088 }
1089 return;
1090 }
1091
1092 ArrayRef<const Expr *> InitExprs =
1093 ILE ? ILE->inits() : CPLIE->getInitExprs();
1094 InitListElements = InitExprs.size();
1095
1096 // If this is a multi-dimensional array new, we will initialize multiple
1097 // elements with each init list element.
1098 QualType AllocType = E->getAllocatedType();
1099 if (const ConstantArrayType *CAT = dyn_cast_or_null<ConstantArrayType>(
1100 Val: AllocType->getAsArrayTypeUnsafe())) {
1101 ElementTy = ConvertTypeForMem(T: AllocType);
1102 CurPtr = CurPtr.withElementType(ElemTy: ElementTy);
1103 InitListElements *= getContext().getConstantArrayElementCount(CA: CAT);
1104 }
1105
1106 // Enter a partial-destruction Cleanup if necessary.
1107 if (DtorKind) {
1108 AllocaTrackerRAII AllocaTracker(*this);
1109 // In principle we could tell the Cleanup where we are more
1110 // directly, but the control flow can get so varied here that it
1111 // would actually be quite complex. Therefore we go through an
1112 // alloca.
1113 llvm::Instruction *DominatingIP =
1114 Builder.CreateFlagLoad(Addr: llvm::ConstantInt::getNullValue(Ty: Int8PtrTy));
1115 EndOfInit = CreateTempAlloca(Ty: BeginPtr.getType(), align: getPointerAlign(),
1116 Name: "array.init.end");
1117 pushIrregularPartialArrayCleanup(arrayBegin: BeginPtr.emitRawPointer(CGF&: *this),
1118 arrayEndPointer: EndOfInit, elementType: ElementType, elementAlignment: ElementAlign,
1119 destroyer: getDestroyer(destructionKind: DtorKind));
1120 cast<EHCleanupScope>(Val&: *EHStack.find(sp: EHStack.stable_begin()))
1121 .AddAuxAllocas(Allocas: AllocaTracker.Take());
1122 DeferredDeactivationCleanupStack.push_back(
1123 Elt: {.Cleanup: EHStack.stable_begin(), .DominatingIP: DominatingIP});
1124 pushedCleanup = true;
1125 }
1126
1127 CharUnits StartAlign = CurPtr.getAlignment();
1128 unsigned i = 0;
1129 for (const Expr *IE : InitExprs) {
1130 // Tell the cleanup that it needs to destroy up to this
1131 // element. TODO: some of these stores can be trivially
1132 // observed to be unnecessary.
1133 if (EndOfInit.isValid()) {
1134 Builder.CreateStore(Val: CurPtr.emitRawPointer(CGF&: *this), Addr: EndOfInit);
1135 }
1136 // FIXME: If the last initializer is an incomplete initializer list for
1137 // an array, and we have an array filler, we can fold together the two
1138 // initialization loops.
1139 StoreAnyExprIntoOneUnit(CGF&: *this, Init: IE, AllocType: IE->getType(), NewPtr: CurPtr,
1140 MayOverlap: AggValueSlot::DoesNotOverlap);
1141 CurPtr = Address(Builder.CreateInBoundsGEP(Ty: CurPtr.getElementType(),
1142 Ptr: CurPtr.emitRawPointer(CGF&: *this),
1143 IdxList: Builder.getSize(N: 1),
1144 Name: "array.exp.next"),
1145 CurPtr.getElementType(),
1146 StartAlign.alignmentAtOffset(offset: (++i) * ElementSize));
1147 }
1148
1149 // The remaining elements are filled with the array filler expression.
1150 Init = ILE ? ILE->getArrayFiller() : CPLIE->getArrayFiller();
1151
1152 // Extract the initializer for the individual array elements by pulling
1153 // out the array filler from all the nested initializer lists. This avoids
1154 // generating a nested loop for the initialization.
1155 while (Init && Init->getType()->isConstantArrayType()) {
1156 auto *SubILE = dyn_cast<InitListExpr>(Val: Init);
1157 if (!SubILE)
1158 break;
1159 assert(SubILE->getNumInits() == 0 && "explicit inits in array filler?");
1160 Init = SubILE->getArrayFiller();
1161 }
1162
1163 // Switch back to initializing one base element at a time.
1164 CurPtr = CurPtr.withElementType(ElemTy: BeginPtr.getElementType());
1165 }
1166
1167 // If all elements have already been initialized, skip any further
1168 // initialization.
1169 llvm::ConstantInt *ConstNum = dyn_cast<llvm::ConstantInt>(Val: NumElements);
1170 if (ConstNum && ConstNum->getZExtValue() <= InitListElements) {
1171 return;
1172 }
1173
1174 assert(Init && "have trailing elements to initialize but no initializer");
1175
1176 // If this is a constructor call, try to optimize it out, and failing that
1177 // emit a single loop to initialize all remaining elements.
1178 if (const CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Val: Init)) {
1179 CXXConstructorDecl *Ctor = CCE->getConstructor();
1180 if (Ctor->isTrivial()) {
1181 // If new expression did not specify value-initialization, then there
1182 // is no initialization.
1183 if (!CCE->requiresZeroInitialization() || Ctor->getParent()->isEmpty())
1184 return;
1185
1186 if (TryMemsetInitialization())
1187 return;
1188 }
1189
1190 // Store the new Cleanup position for irregular Cleanups.
1191 //
1192 // FIXME: Share this cleanup with the constructor call emission rather than
1193 // having it create a cleanup of its own.
1194 if (EndOfInit.isValid())
1195 Builder.CreateStore(Val: CurPtr.emitRawPointer(CGF&: *this), Addr: EndOfInit);
1196
1197 // Emit a constructor call loop to initialize the remaining elements.
1198 if (InitListElements)
1199 NumElements = Builder.CreateSub(
1200 LHS: NumElements,
1201 RHS: llvm::ConstantInt::get(Ty: NumElements->getType(), V: InitListElements));
1202 EmitCXXAggrConstructorCall(D: Ctor, NumElements, ArrayPtr: CurPtr, E: CCE,
1203 /*NewPointerIsChecked*/ true,
1204 ZeroInitialization: CCE->requiresZeroInitialization());
1205 return;
1206 }
1207
1208 // If this is value-initialization, we can usually use memset.
1209 ImplicitValueInitExpr IVIE(ElementType);
1210 if (isa<ImplicitValueInitExpr>(Val: Init)) {
1211 if (TryMemsetInitialization())
1212 return;
1213
1214 // Switch to an ImplicitValueInitExpr for the element type. This handles
1215 // only one case: multidimensional array new of pointers to members. In
1216 // all other cases, we already have an initializer for the array element.
1217 Init = &IVIE;
1218 }
1219
1220 // At this point we should have found an initializer for the individual
1221 // elements of the array.
1222 assert(getContext().hasSameUnqualifiedType(ElementType, Init->getType()) &&
1223 "got wrong type of element to initialize");
1224
1225 // If we have an empty initializer list, we can usually use memset.
1226 if (auto *ILE = dyn_cast<InitListExpr>(Val: Init))
1227 if (ILE->getNumInits() == 0 && TryMemsetInitialization())
1228 return;
1229
1230 // If we have a struct whose every field is value-initialized, we can
1231 // usually use memset.
1232 if (auto *ILE = dyn_cast<InitListExpr>(Val: Init)) {
1233 if (const RecordType *RType =
1234 ILE->getType()->getAsCanonical<RecordType>()) {
1235 if (RType->getDecl()->isStruct()) {
1236 const RecordDecl *RD = RType->getDecl()->getDefinitionOrSelf();
1237 unsigned NumElements = 0;
1238 if (auto *CXXRD = dyn_cast<CXXRecordDecl>(Val: RD))
1239 NumElements = CXXRD->getNumBases();
1240 for (auto *Field : RD->fields())
1241 if (!Field->isUnnamedBitField())
1242 ++NumElements;
1243 // FIXME: Recurse into nested InitListExprs.
1244 if (ILE->getNumInits() == NumElements)
1245 for (unsigned i = 0, e = ILE->getNumInits(); i != e; ++i)
1246 if (!isa<ImplicitValueInitExpr>(Val: ILE->getInit(Init: i)))
1247 --NumElements;
1248 if (ILE->getNumInits() == NumElements && TryMemsetInitialization())
1249 return;
1250 }
1251 }
1252 }
1253
1254 // Create the loop blocks.
1255 llvm::BasicBlock *EntryBB = Builder.GetInsertBlock();
1256 llvm::BasicBlock *LoopBB = createBasicBlock(name: "new.loop");
1257 llvm::BasicBlock *ContBB = createBasicBlock(name: "new.loop.end");
1258
1259 // Find the end of the array, hoisted out of the loop.
1260 llvm::Value *EndPtr = Builder.CreateInBoundsGEP(
1261 Ty: BeginPtr.getElementType(), Ptr: BeginPtr.emitRawPointer(CGF&: *this), IdxList: NumElements,
1262 Name: "array.end");
1263
1264 // If the number of elements isn't constant, we have to now check if there is
1265 // anything left to initialize.
1266 if (!ConstNum) {
1267 llvm::Value *IsEmpty = Builder.CreateICmpEQ(LHS: CurPtr.emitRawPointer(CGF&: *this),
1268 RHS: EndPtr, Name: "array.isempty");
1269 Builder.CreateCondBr(Cond: IsEmpty, True: ContBB, False: LoopBB);
1270 }
1271
1272 // Enter the loop.
1273 EmitBlock(BB: LoopBB);
1274
1275 // Set up the current-element phi.
1276 llvm::PHINode *CurPtrPhi =
1277 Builder.CreatePHI(Ty: CurPtr.getType(), NumReservedValues: 2, Name: "array.cur");
1278 CurPtrPhi->addIncoming(V: CurPtr.emitRawPointer(CGF&: *this), BB: EntryBB);
1279
1280 CurPtr = Address(CurPtrPhi, CurPtr.getElementType(), ElementAlign);
1281
1282 // Store the new Cleanup position for irregular Cleanups.
1283 if (EndOfInit.isValid())
1284 Builder.CreateStore(Val: CurPtr.emitRawPointer(CGF&: *this), Addr: EndOfInit);
1285
1286 // Enter a partial-destruction Cleanup if necessary.
1287 if (!pushedCleanup && needsEHCleanup(kind: DtorKind)) {
1288 llvm::Instruction *DominatingIP =
1289 Builder.CreateFlagLoad(Addr: llvm::ConstantInt::getNullValue(Ty: Int8PtrTy));
1290 pushRegularPartialArrayCleanup(arrayBegin: BeginPtr.emitRawPointer(CGF&: *this),
1291 arrayEnd: CurPtr.emitRawPointer(CGF&: *this), elementType: ElementType,
1292 elementAlignment: ElementAlign, destroyer: getDestroyer(destructionKind: DtorKind));
1293 DeferredDeactivationCleanupStack.push_back(
1294 Elt: {.Cleanup: EHStack.stable_begin(), .DominatingIP: DominatingIP});
1295 }
1296
1297 // Emit the initializer into this element.
1298 StoreAnyExprIntoOneUnit(CGF&: *this, Init, AllocType: Init->getType(), NewPtr: CurPtr,
1299 MayOverlap: AggValueSlot::DoesNotOverlap);
1300
1301 // Leave the Cleanup if we entered one.
1302 deactivation.ForceDeactivate();
1303
1304 // Advance to the next element by adjusting the pointer type as necessary.
1305 llvm::Value *NextPtr = Builder.CreateConstInBoundsGEP1_32(
1306 Ty: ElementTy, Ptr: CurPtr.emitRawPointer(CGF&: *this), Idx0: 1, Name: "array.next");
1307
1308 // Check whether we've gotten to the end of the array and, if so,
1309 // exit the loop.
1310 llvm::Value *IsEnd = Builder.CreateICmpEQ(LHS: NextPtr, RHS: EndPtr, Name: "array.atend");
1311 Builder.CreateCondBr(Cond: IsEnd, True: ContBB, False: LoopBB);
1312 CurPtrPhi->addIncoming(V: NextPtr, BB: Builder.GetInsertBlock());
1313
1314 EmitBlock(BB: ContBB);
1315}
1316
1317static void EmitNewInitializer(CodeGenFunction &CGF, const CXXNewExpr *E,
1318 QualType ElementType, llvm::Type *ElementTy,
1319 Address NewPtr, llvm::Value *NumElements,
1320 llvm::Value *AllocSizeWithoutCookie) {
1321 ApplyDebugLocation DL(CGF, E);
1322 if (E->isArray())
1323 CGF.EmitNewArrayInitializer(E, ElementType, ElementTy, BeginPtr: NewPtr, NumElements,
1324 AllocSizeWithoutCookie);
1325 else if (const Expr *Init = E->getInitializer())
1326 StoreAnyExprIntoOneUnit(CGF, Init, AllocType: E->getAllocatedType(), NewPtr,
1327 MayOverlap: AggValueSlot::DoesNotOverlap);
1328}
1329
1330/// Emit a call to an operator new or operator delete function, as implicitly
1331/// created by new-expressions and delete-expressions.
1332static RValue EmitNewDeleteCall(CodeGenFunction &CGF,
1333 const FunctionDecl *CalleeDecl,
1334 const FunctionProtoType *CalleeType,
1335 const CallArgList &Args) {
1336 llvm::CallBase *CallOrInvoke;
1337 llvm::Constant *CalleePtr = CGF.CGM.GetAddrOfFunction(GD: CalleeDecl);
1338 CGCallee Callee = CGCallee::forDirect(functionPtr: CalleePtr, abstractInfo: GlobalDecl(CalleeDecl));
1339 RValue RV = CGF.EmitCall(CallInfo: CGF.CGM.getTypes().arrangeFreeFunctionCall(
1340 Args, Ty: CalleeType, /*ChainCall=*/false),
1341 Callee, ReturnValue: ReturnValueSlot(), Args, CallOrInvoke: &CallOrInvoke);
1342
1343 /// C++1y [expr.new]p10:
1344 /// [In a new-expression,] an implementation is allowed to omit a call
1345 /// to a replaceable global allocation function.
1346 ///
1347 /// We model such elidable calls with the 'builtin' attribute.
1348 llvm::Function *Fn = dyn_cast<llvm::Function>(Val: CalleePtr);
1349 if (CalleeDecl->isReplaceableGlobalAllocationFunction() && Fn &&
1350 Fn->hasFnAttribute(Kind: llvm::Attribute::NoBuiltin)) {
1351 CallOrInvoke->addFnAttr(Kind: llvm::Attribute::Builtin);
1352 }
1353
1354 return RV;
1355}
1356
1357RValue CodeGenFunction::EmitBuiltinNewDeleteCall(const FunctionProtoType *Type,
1358 const CallExpr *TheCall,
1359 bool IsDelete) {
1360 CallArgList Args;
1361 EmitCallArgs(Args, Prototype: Type, ArgRange: TheCall->arguments());
1362 // Find the allocation or deallocation function that we're calling.
1363 ASTContext &Ctx = getContext();
1364 DeclarationName Name =
1365 Ctx.DeclarationNames.getCXXOperatorName(Op: IsDelete ? OO_Delete : OO_New);
1366
1367 for (auto *Decl : Ctx.getTranslationUnitDecl()->lookup(Name))
1368 if (auto *FD = dyn_cast<FunctionDecl>(Val: Decl))
1369 if (Ctx.hasSameType(T1: FD->getType(), T2: QualType(Type, 0))) {
1370 RValue RV = EmitNewDeleteCall(CGF&: *this, CalleeDecl: FD, CalleeType: Type, Args);
1371 if (auto *CB = dyn_cast_if_present<llvm::CallBase>(Val: RV.getScalarVal())) {
1372 if (SanOpts.has(K: SanitizerKind::AllocToken)) {
1373 // Set !alloc_token metadata.
1374 EmitAllocToken(CB, E: TheCall);
1375 }
1376 }
1377 return RV;
1378 }
1379 llvm_unreachable("predeclared global operator new/delete is missing");
1380}
1381
1382namespace {
1383/// A cleanup to call the given 'operator delete' function upon abnormal
1384/// exit from a new expression. Templated on a traits type that deals with
1385/// ensuring that the arguments dominate the cleanup if necessary.
1386template <typename Traits>
1387class CallDeleteDuringNew final : public EHScopeStack::Cleanup {
1388 /// Type used to hold llvm::Value*s.
1389 typedef typename Traits::ValueTy ValueTy;
1390 /// Type used to hold RValues.
1391 typedef typename Traits::RValueTy RValueTy;
1392 struct PlacementArg {
1393 RValueTy ArgValue;
1394 QualType ArgType;
1395 };
1396
1397 unsigned NumPlacementArgs : 30;
1398 LLVM_PREFERRED_TYPE(AlignedAllocationMode)
1399 unsigned PassAlignmentToPlacementDelete : 1;
1400 const FunctionDecl *OperatorDelete;
1401 RValueTy TypeIdentity;
1402 ValueTy Ptr;
1403 ValueTy AllocSize;
1404 CharUnits AllocAlign;
1405
1406 PlacementArg *getPlacementArgs() {
1407 return reinterpret_cast<PlacementArg *>(this + 1);
1408 }
1409
1410public:
1411 static size_t getExtraSize(size_t NumPlacementArgs) {
1412 return NumPlacementArgs * sizeof(PlacementArg);
1413 }
1414
1415 CallDeleteDuringNew(size_t NumPlacementArgs,
1416 const FunctionDecl *OperatorDelete, RValueTy TypeIdentity,
1417 ValueTy Ptr, ValueTy AllocSize,
1418 const ImplicitAllocationParameters &IAP,
1419 CharUnits AllocAlign)
1420 : NumPlacementArgs(NumPlacementArgs),
1421 PassAlignmentToPlacementDelete(isAlignedAllocation(Mode: IAP.PassAlignment)),
1422 OperatorDelete(OperatorDelete), TypeIdentity(TypeIdentity), Ptr(Ptr),
1423 AllocSize(AllocSize), AllocAlign(AllocAlign) {}
1424
1425 void setPlacementArg(unsigned I, RValueTy Arg, QualType Type) {
1426 assert(I < NumPlacementArgs && "index out of range");
1427 getPlacementArgs()[I] = {Arg, Type};
1428 }
1429
1430 void Emit(CodeGenFunction &CGF, Flags flags) override {
1431 const auto *FPT = OperatorDelete->getType()->castAs<FunctionProtoType>();
1432 CallArgList DeleteArgs;
1433 unsigned FirstNonTypeArg = 0;
1434 TypeAwareAllocationMode TypeAwareDeallocation = TypeAwareAllocationMode::No;
1435 if (OperatorDelete->isTypeAwareOperatorNewOrDelete()) {
1436 TypeAwareDeallocation = TypeAwareAllocationMode::Yes;
1437 QualType SpecializedTypeIdentity = FPT->getParamType(i: 0);
1438 ++FirstNonTypeArg;
1439 DeleteArgs.add(rvalue: Traits::get(CGF, TypeIdentity), type: SpecializedTypeIdentity);
1440 }
1441 // The first argument after type-identity parameter (if any) is always
1442 // a void* (or C* for a destroying operator delete for class type C).
1443 DeleteArgs.add(rvalue: Traits::get(CGF, Ptr), type: FPT->getParamType(i: FirstNonTypeArg));
1444
1445 // Figure out what other parameters we should be implicitly passing.
1446 UsualDeleteParams Params;
1447 if (NumPlacementArgs) {
1448 // A placement deallocation function is implicitly passed an alignment
1449 // if the placement allocation function was, but is never passed a size.
1450 Params.Alignment =
1451 alignedAllocationModeFromBool(IsAligned: PassAlignmentToPlacementDelete);
1452 Params.TypeAwareDelete = TypeAwareDeallocation;
1453 Params.Size = isTypeAwareAllocation(Mode: Params.TypeAwareDelete);
1454 } else {
1455 // For a non-placement new-expression, 'operator delete' can take a
1456 // size and/or an alignment if it has the right parameters.
1457 Params = OperatorDelete->getUsualDeleteParams();
1458 }
1459
1460 assert(!Params.DestroyingDelete &&
1461 "should not call destroying delete in a new-expression");
1462
1463 // The second argument can be a std::size_t (for non-placement delete).
1464 if (Params.Size)
1465 DeleteArgs.add(rvalue: Traits::get(CGF, AllocSize),
1466 type: CGF.getContext().getSizeType());
1467
1468 // The next (second or third) argument can be a std::align_val_t, which
1469 // is an enum whose underlying type is std::size_t.
1470 // FIXME: Use the right type as the parameter type. Note that in a call
1471 // to operator delete(size_t, ...), we may not have it available.
1472 if (isAlignedAllocation(Mode: Params.Alignment))
1473 DeleteArgs.add(rvalue: RValue::get(V: llvm::ConstantInt::get(
1474 Ty: CGF.SizeTy, V: AllocAlign.getQuantity())),
1475 type: CGF.getContext().getSizeType());
1476
1477 // Pass the rest of the arguments, which must match exactly.
1478 for (unsigned I = 0; I != NumPlacementArgs; ++I) {
1479 auto Arg = getPlacementArgs()[I];
1480 DeleteArgs.add(rvalue: Traits::get(CGF, Arg.ArgValue), type: Arg.ArgType);
1481 }
1482
1483 // Call 'operator delete'.
1484 EmitNewDeleteCall(CGF, CalleeDecl: OperatorDelete, CalleeType: FPT, Args: DeleteArgs);
1485 }
1486};
1487} // namespace
1488
1489/// Enter a cleanup to call 'operator delete' if the initializer in a
1490/// new-expression throws.
1491static void EnterNewDeleteCleanup(CodeGenFunction &CGF, const CXXNewExpr *E,
1492 RValue TypeIdentity, Address NewPtr,
1493 llvm::Value *AllocSize, CharUnits AllocAlign,
1494 const CallArgList &NewArgs) {
1495 unsigned NumNonPlacementArgs = E->getNumImplicitArgs();
1496
1497 // If we're not inside a conditional branch, then the cleanup will
1498 // dominate and we can do the easier (and more efficient) thing.
1499 if (!CGF.isInConditionalBranch()) {
1500 struct DirectCleanupTraits {
1501 typedef llvm::Value *ValueTy;
1502 typedef RValue RValueTy;
1503 static RValue get(CodeGenFunction &, ValueTy V) { return RValue::get(V); }
1504 static RValue get(CodeGenFunction &, RValueTy V) { return V; }
1505 };
1506
1507 typedef CallDeleteDuringNew<DirectCleanupTraits> DirectCleanup;
1508
1509 DirectCleanup *Cleanup = CGF.EHStack.pushCleanupWithExtra<DirectCleanup>(
1510 Kind: EHCleanup, N: E->getNumPlacementArgs(), A: E->getOperatorDelete(),
1511 A: TypeIdentity, A: NewPtr.emitRawPointer(CGF), A: AllocSize,
1512 A: E->implicitAllocationParameters(), A: AllocAlign);
1513 for (unsigned I = 0, N = E->getNumPlacementArgs(); I != N; ++I) {
1514 auto &Arg = NewArgs[I + NumNonPlacementArgs];
1515 Cleanup->setPlacementArg(I, Arg: Arg.getRValue(CGF), Type: Arg.Ty);
1516 }
1517
1518 return;
1519 }
1520
1521 // Otherwise, we need to save all this stuff.
1522 DominatingValue<RValue>::saved_type SavedNewPtr =
1523 DominatingValue<RValue>::save(CGF, value: RValue::get(Addr: NewPtr, CGF));
1524 DominatingValue<RValue>::saved_type SavedAllocSize =
1525 DominatingValue<RValue>::save(CGF, value: RValue::get(V: AllocSize));
1526 DominatingValue<RValue>::saved_type SavedTypeIdentity =
1527 DominatingValue<RValue>::save(CGF, value: TypeIdentity);
1528 struct ConditionalCleanupTraits {
1529 typedef DominatingValue<RValue>::saved_type ValueTy;
1530 typedef DominatingValue<RValue>::saved_type RValueTy;
1531 static RValue get(CodeGenFunction &CGF, ValueTy V) {
1532 return V.restore(CGF);
1533 }
1534 };
1535 typedef CallDeleteDuringNew<ConditionalCleanupTraits> ConditionalCleanup;
1536
1537 ConditionalCleanup *Cleanup =
1538 CGF.EHStack.pushCleanupWithExtra<ConditionalCleanup>(
1539 Kind: EHCleanup, N: E->getNumPlacementArgs(), A: E->getOperatorDelete(),
1540 A: SavedTypeIdentity, A: SavedNewPtr, A: SavedAllocSize,
1541 A: E->implicitAllocationParameters(), A: AllocAlign);
1542 for (unsigned I = 0, N = E->getNumPlacementArgs(); I != N; ++I) {
1543 auto &Arg = NewArgs[I + NumNonPlacementArgs];
1544 Cleanup->setPlacementArg(
1545 I, Arg: DominatingValue<RValue>::save(CGF, value: Arg.getRValue(CGF)), Type: Arg.Ty);
1546 }
1547
1548 CGF.initFullExprCleanup();
1549}
1550
1551llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
1552 // The element type being allocated.
1553 QualType allocType = getContext().getBaseElementType(QT: E->getAllocatedType());
1554
1555 // 1. Build a call to the allocation function.
1556 FunctionDecl *allocator = E->getOperatorNew();
1557
1558 // If there is a brace-initializer or C++20 parenthesized initializer, cannot
1559 // allocate fewer elements than inits.
1560 unsigned minElements = 0;
1561 unsigned IndexOfAlignArg = 1;
1562 if (E->isArray() && E->hasInitializer()) {
1563 const Expr *Init = E->getInitializer();
1564 const InitListExpr *ILE = dyn_cast<InitListExpr>(Val: Init);
1565 const CXXParenListInitExpr *CPLIE = dyn_cast<CXXParenListInitExpr>(Val: Init);
1566 const Expr *IgnoreParen = Init->IgnoreParenImpCasts();
1567 if ((ILE && ILE->isStringLiteralInit()) ||
1568 isa<StringLiteral>(Val: IgnoreParen) || isa<ObjCEncodeExpr>(Val: IgnoreParen)) {
1569 minElements =
1570 cast<ConstantArrayType>(Val: Init->getType()->getAsArrayTypeUnsafe())
1571 ->getZExtSize();
1572 } else if (ILE || CPLIE) {
1573 minElements = ILE ? ILE->getNumInits() : CPLIE->getInitExprs().size();
1574 }
1575 }
1576
1577 llvm::Value *numElements = nullptr;
1578 llvm::Value *allocSizeWithoutCookie = nullptr;
1579 llvm::Value *allocSize = EmitCXXNewAllocSize(
1580 CGF&: *this, e: E, minElements, numElements, sizeWithoutCookie&: allocSizeWithoutCookie);
1581 CharUnits allocAlign = getContext().getTypeAlignInChars(T: allocType);
1582
1583 // Emit the allocation call. If the allocator is a global placement
1584 // operator, just "inline" it directly.
1585 Address allocation = Address::invalid();
1586 CallArgList allocatorArgs;
1587 RValue TypeIdentityArg;
1588 if (allocator->isReservedGlobalPlacementOperator()) {
1589 assert(E->getNumPlacementArgs() == 1);
1590 const Expr *arg = *E->placement_arguments().begin();
1591
1592 LValueBaseInfo BaseInfo;
1593 allocation = EmitPointerWithAlignment(Addr: arg, BaseInfo: &BaseInfo);
1594
1595 // The pointer expression will, in many cases, be an opaque void*.
1596 // In these cases, discard the computed alignment and use the
1597 // formal alignment of the allocated type.
1598 if (BaseInfo.getAlignmentSource() != AlignmentSource::Decl)
1599 allocation.setAlignment(allocAlign);
1600
1601 // Set up allocatorArgs for the call to operator delete if it's not
1602 // the reserved global operator.
1603 if (E->getOperatorDelete() &&
1604 !E->getOperatorDelete()->isReservedGlobalPlacementOperator()) {
1605 allocatorArgs.add(rvalue: RValue::get(V: allocSize), type: getContext().getSizeType());
1606 allocatorArgs.add(rvalue: RValue::get(Addr: allocation, CGF&: *this), type: arg->getType());
1607 }
1608
1609 } else {
1610 const FunctionProtoType *allocatorType =
1611 allocator->getType()->castAs<FunctionProtoType>();
1612 ImplicitAllocationParameters IAP = E->implicitAllocationParameters();
1613 unsigned ParamsToSkip = 0;
1614 if (isTypeAwareAllocation(Mode: IAP.PassTypeIdentity)) {
1615 QualType SpecializedTypeIdentity = allocatorType->getParamType(i: 0);
1616 CXXScalarValueInitExpr TypeIdentityParam(SpecializedTypeIdentity, nullptr,
1617 SourceLocation());
1618 TypeIdentityArg = EmitAnyExprToTemp(E: &TypeIdentityParam);
1619 allocatorArgs.add(rvalue: TypeIdentityArg, type: SpecializedTypeIdentity);
1620 ++ParamsToSkip;
1621 ++IndexOfAlignArg;
1622 }
1623 // The allocation size is the first argument.
1624 QualType sizeType = getContext().getSizeType();
1625 allocatorArgs.add(rvalue: RValue::get(V: allocSize), type: sizeType);
1626 ++ParamsToSkip;
1627
1628 if (allocSize != allocSizeWithoutCookie) {
1629 CharUnits cookieAlign = getSizeAlign(); // FIXME: Ask the ABI.
1630 allocAlign = std::max(a: allocAlign, b: cookieAlign);
1631 }
1632
1633 // The allocation alignment may be passed as the second argument.
1634 if (isAlignedAllocation(Mode: IAP.PassAlignment)) {
1635 QualType AlignValT = sizeType;
1636 if (allocatorType->getNumParams() > IndexOfAlignArg) {
1637 AlignValT = allocatorType->getParamType(i: IndexOfAlignArg);
1638 assert(getContext().hasSameUnqualifiedType(
1639 AlignValT->castAsEnumDecl()->getIntegerType(), sizeType) &&
1640 "wrong type for alignment parameter");
1641 ++ParamsToSkip;
1642 } else {
1643 // Corner case, passing alignment to 'operator new(size_t, ...)'.
1644 assert(allocator->isVariadic() && "can't pass alignment to allocator");
1645 }
1646 allocatorArgs.add(
1647 rvalue: RValue::get(V: llvm::ConstantInt::get(Ty: SizeTy, V: allocAlign.getQuantity())),
1648 type: AlignValT);
1649 }
1650
1651 // FIXME: Why do we not pass a CalleeDecl here?
1652 EmitCallArgs(Args&: allocatorArgs, Prototype: allocatorType, ArgRange: E->placement_arguments(),
1653 /*AC*/ AbstractCallee(), /*ParamsToSkip*/ ParamsToSkip);
1654
1655 RValue RV =
1656 EmitNewDeleteCall(CGF&: *this, CalleeDecl: allocator, CalleeType: allocatorType, Args: allocatorArgs);
1657
1658 if (auto *newCall = dyn_cast<llvm::CallBase>(Val: RV.getScalarVal())) {
1659 if (auto *CGDI = getDebugInfo()) {
1660 // Set !heapallocsite metadata on the call to operator new.
1661 CGDI->addHeapAllocSiteMetadata(CallSite: newCall, AllocatedTy: allocType, Loc: E->getExprLoc());
1662 }
1663 if (SanOpts.has(K: SanitizerKind::AllocToken)) {
1664 // Set !alloc_token metadata.
1665 EmitAllocToken(CB: newCall, AllocType: allocType);
1666 }
1667 }
1668
1669 // If this was a call to a global replaceable allocation function that does
1670 // not take an alignment argument, the allocator is known to produce
1671 // storage that's suitably aligned for any object that fits, up to a known
1672 // threshold. Otherwise assume it's suitably aligned for the allocated type.
1673 CharUnits allocationAlign = allocAlign;
1674 if (!E->passAlignment() &&
1675 allocator->isReplaceableGlobalAllocationFunction()) {
1676 unsigned AllocatorAlign = llvm::bit_floor(Value: std::min<uint64_t>(
1677 a: Target.getNewAlign(), b: getContext().getTypeSize(T: allocType)));
1678 allocationAlign = std::max(
1679 a: allocationAlign, b: getContext().toCharUnitsFromBits(BitSize: AllocatorAlign));
1680 }
1681
1682 allocation = Address(RV.getScalarVal(), Int8Ty, allocationAlign);
1683 }
1684
1685 // Emit a null check on the allocation result if the allocation
1686 // function is allowed to return null (because it has a non-throwing
1687 // exception spec or is the reserved placement new) and we have an
1688 // interesting initializer will be running sanitizers on the initialization.
1689 bool nullCheck = E->shouldNullCheckAllocation() &&
1690 (!allocType.isPODType(Context: getContext()) || E->hasInitializer() ||
1691 sanitizePerformTypeCheck());
1692
1693 llvm::BasicBlock *nullCheckBB = nullptr;
1694 llvm::BasicBlock *contBB = nullptr;
1695
1696 // The null-check means that the initializer is conditionally
1697 // evaluated.
1698 ConditionalEvaluation conditional(*this);
1699
1700 if (nullCheck) {
1701 conditional.begin(CGF&: *this);
1702
1703 nullCheckBB = Builder.GetInsertBlock();
1704 llvm::BasicBlock *notNullBB = createBasicBlock(name: "new.notnull");
1705 contBB = createBasicBlock(name: "new.cont");
1706
1707 llvm::Value *isNull = Builder.CreateIsNull(Addr: allocation, Name: "new.isnull");
1708 Builder.CreateCondBr(Cond: isNull, True: contBB, False: notNullBB);
1709 EmitBlock(BB: notNullBB);
1710 }
1711
1712 // If there's an operator delete, enter a cleanup to call it if an
1713 // exception is thrown.
1714 EHScopeStack::stable_iterator operatorDeleteCleanup;
1715 llvm::Instruction *cleanupDominator = nullptr;
1716 if (E->getOperatorDelete() &&
1717 !E->getOperatorDelete()->isReservedGlobalPlacementOperator()) {
1718 EnterNewDeleteCleanup(CGF&: *this, E, TypeIdentity: TypeIdentityArg, NewPtr: allocation, AllocSize: allocSize,
1719 AllocAlign: allocAlign, NewArgs: allocatorArgs);
1720 operatorDeleteCleanup = EHStack.stable_begin();
1721 cleanupDominator = Builder.CreateUnreachable();
1722 }
1723
1724 assert((allocSize == allocSizeWithoutCookie) ==
1725 CalculateCookiePadding(*this, E).isZero());
1726 if (allocSize != allocSizeWithoutCookie) {
1727 assert(E->isArray());
1728 allocation = CGM.getCXXABI().InitializeArrayCookie(
1729 CGF&: *this, NewPtr: allocation, NumElements: numElements, expr: E, ElementType: allocType);
1730 }
1731
1732 llvm::Type *elementTy = ConvertTypeForMem(T: allocType);
1733 Address result = allocation.withElementType(ElemTy: elementTy);
1734
1735 // Passing pointer through launder.invariant.group to avoid propagation of
1736 // vptrs information which may be included in previous type.
1737 // To not break LTO with different optimizations levels, we do it regardless
1738 // of optimization level.
1739 if (CGM.getCodeGenOpts().StrictVTablePointers &&
1740 allocator->isReservedGlobalPlacementOperator())
1741 result = Builder.CreateLaunderInvariantGroup(Addr: result);
1742
1743 // Emit sanitizer checks for pointer value now, so that in the case of an
1744 // array it was checked only once and not at each constructor call. We may
1745 // have already checked that the pointer is non-null.
1746 // FIXME: If we have an array cookie and a potentially-throwing allocator,
1747 // we'll null check the wrong pointer here.
1748 SanitizerSet SkippedChecks;
1749 SkippedChecks.set(K: SanitizerKind::Null, Value: nullCheck);
1750 EmitTypeCheck(TCK: CodeGenFunction::TCK_ConstructorCall,
1751 Loc: E->getAllocatedTypeSourceInfo()->getTypeLoc().getBeginLoc(),
1752 Addr: result, Type: allocType, Alignment: result.getAlignment(), SkippedChecks,
1753 ArraySize: numElements);
1754
1755 EmitNewInitializer(CGF&: *this, E, ElementType: allocType, ElementTy: elementTy, NewPtr: result, NumElements: numElements,
1756 AllocSizeWithoutCookie: allocSizeWithoutCookie);
1757 llvm::Value *resultPtr = result.emitRawPointer(CGF&: *this);
1758
1759 // Deactivate the 'operator delete' cleanup if we finished
1760 // initialization.
1761 if (operatorDeleteCleanup.isValid()) {
1762 DeactivateCleanupBlock(Cleanup: operatorDeleteCleanup, DominatingIP: cleanupDominator);
1763 cleanupDominator->eraseFromParent();
1764 }
1765
1766 if (nullCheck) {
1767 conditional.end(CGF&: *this);
1768
1769 llvm::BasicBlock *notNullBB = Builder.GetInsertBlock();
1770 EmitBlock(BB: contBB);
1771
1772 llvm::PHINode *PHI = Builder.CreatePHI(Ty: resultPtr->getType(), NumReservedValues: 2);
1773 PHI->addIncoming(V: resultPtr, BB: notNullBB);
1774 PHI->addIncoming(V: llvm::Constant::getNullValue(Ty: resultPtr->getType()),
1775 BB: nullCheckBB);
1776
1777 resultPtr = PHI;
1778 }
1779
1780 return resultPtr;
1781}
1782
1783void CodeGenFunction::EmitDeleteCall(const FunctionDecl *DeleteFD,
1784 llvm::Value *DeletePtr, QualType DeleteTy,
1785 llvm::Value *NumElements,
1786 CharUnits CookieSize) {
1787 assert((!NumElements && CookieSize.isZero()) ||
1788 DeleteFD->getOverloadedOperator() == OO_Array_Delete);
1789
1790 const auto *DeleteFTy = DeleteFD->getType()->castAs<FunctionProtoType>();
1791 CallArgList DeleteArgs;
1792
1793 auto Params = DeleteFD->getUsualDeleteParams();
1794 auto ParamTypeIt = DeleteFTy->param_type_begin();
1795
1796 std::optional<llvm::AllocaInst *> TagAlloca;
1797 auto EmitTag = [&](QualType TagType, const char *TagName) {
1798 assert(!TagAlloca);
1799 llvm::Type *Ty = getTypes().ConvertType(T: TagType);
1800 CharUnits Align = CGM.getNaturalTypeAlignment(T: TagType);
1801 llvm::AllocaInst *TagAllocation = CreateTempAlloca(Ty, Name: TagName);
1802 TagAllocation->setAlignment(Align.getAsAlign());
1803 DeleteArgs.add(rvalue: RValue::getAggregate(addr: Address(TagAllocation, Ty, Align)),
1804 type: TagType);
1805 TagAlloca = TagAllocation;
1806 };
1807
1808 // Pass std::type_identity tag if present
1809 if (isTypeAwareAllocation(Mode: Params.TypeAwareDelete))
1810 EmitTag(*ParamTypeIt++, "typeaware.delete.tag");
1811
1812 // Pass the pointer itself.
1813 QualType ArgTy = *ParamTypeIt++;
1814 DeleteArgs.add(rvalue: RValue::get(V: DeletePtr), type: ArgTy);
1815
1816 // Pass the std::destroying_delete tag if present.
1817 if (Params.DestroyingDelete)
1818 EmitTag(*ParamTypeIt++, "destroying.delete.tag");
1819
1820 // Pass the size if the delete function has a size_t parameter.
1821 if (Params.Size) {
1822 QualType SizeType = *ParamTypeIt++;
1823 CharUnits DeleteTypeSize = getContext().getTypeSizeInChars(T: DeleteTy);
1824 llvm::Value *Size = llvm::ConstantInt::get(Ty: ConvertType(T: SizeType),
1825 V: DeleteTypeSize.getQuantity());
1826
1827 // For array new, multiply by the number of elements.
1828 if (NumElements)
1829 Size = Builder.CreateMul(LHS: Size, RHS: NumElements);
1830
1831 // If there is a cookie, add the cookie size.
1832 if (!CookieSize.isZero())
1833 Size = Builder.CreateAdd(
1834 LHS: Size, RHS: llvm::ConstantInt::get(Ty: SizeTy, V: CookieSize.getQuantity()));
1835
1836 DeleteArgs.add(rvalue: RValue::get(V: Size), type: SizeType);
1837 }
1838
1839 // Pass the alignment if the delete function has an align_val_t parameter.
1840 if (isAlignedAllocation(Mode: Params.Alignment)) {
1841 QualType AlignValType = *ParamTypeIt++;
1842 CharUnits DeleteTypeAlign =
1843 getContext().toCharUnitsFromBits(BitSize: getContext().getTypeAlignIfKnown(
1844 T: DeleteTy, NeedsPreferredAlignment: true /* NeedsPreferredAlignment */));
1845 llvm::Value *Align = llvm::ConstantInt::get(Ty: ConvertType(T: AlignValType),
1846 V: DeleteTypeAlign.getQuantity());
1847 DeleteArgs.add(rvalue: RValue::get(V: Align), type: AlignValType);
1848 }
1849
1850 assert(ParamTypeIt == DeleteFTy->param_type_end() &&
1851 "unknown parameter to usual delete function");
1852
1853 // Emit the call to delete.
1854 EmitNewDeleteCall(CGF&: *this, CalleeDecl: DeleteFD, CalleeType: DeleteFTy, Args: DeleteArgs);
1855
1856 // If call argument lowering didn't use a generated tag argument alloca we
1857 // remove them
1858 if (TagAlloca && (*TagAlloca)->use_empty())
1859 (*TagAlloca)->eraseFromParent();
1860}
1861namespace {
1862/// Calls the given 'operator delete' on a single object.
1863struct CallObjectDelete final : EHScopeStack::Cleanup {
1864 llvm::Value *Ptr;
1865 const FunctionDecl *OperatorDelete;
1866 QualType ElementType;
1867
1868 CallObjectDelete(llvm::Value *Ptr, const FunctionDecl *OperatorDelete,
1869 QualType ElementType)
1870 : Ptr(Ptr), OperatorDelete(OperatorDelete), ElementType(ElementType) {}
1871
1872 void Emit(CodeGenFunction &CGF, Flags flags) override {
1873 CGF.EmitDeleteCall(DeleteFD: OperatorDelete, DeletePtr: Ptr, DeleteTy: ElementType);
1874 }
1875};
1876} // namespace
1877
1878void CodeGenFunction::pushCallObjectDeleteCleanup(
1879 const FunctionDecl *OperatorDelete, llvm::Value *CompletePtr,
1880 QualType ElementType) {
1881 EHStack.pushCleanup<CallObjectDelete>(Kind: NormalAndEHCleanup, A: CompletePtr,
1882 A: OperatorDelete, A: ElementType);
1883}
1884
1885/// Emit the code for deleting a single object with a destroying operator
1886/// delete. If the element type has a non-virtual destructor, Ptr has already
1887/// been converted to the type of the parameter of 'operator delete'. Otherwise
1888/// Ptr points to an object of the static type.
1889static void EmitDestroyingObjectDelete(CodeGenFunction &CGF,
1890 const CXXDeleteExpr *DE, Address Ptr,
1891 QualType ElementType) {
1892 auto *Dtor = ElementType->getAsCXXRecordDecl()->getDestructor();
1893 if (Dtor && Dtor->isVirtual())
1894 CGF.CGM.getCXXABI().emitVirtualObjectDelete(CGF, DE, Ptr, ElementType,
1895 Dtor);
1896 else
1897 CGF.EmitDeleteCall(DeleteFD: DE->getOperatorDelete(), DeletePtr: Ptr.emitRawPointer(CGF),
1898 DeleteTy: ElementType);
1899}
1900
1901/// Emit the code for deleting a single object.
1902/// \return \c true if we started emitting UnconditionalDeleteBlock, \c false
1903/// if not.
1904static bool EmitObjectDelete(CodeGenFunction &CGF, const CXXDeleteExpr *DE,
1905 Address Ptr, QualType ElementType,
1906 llvm::BasicBlock *UnconditionalDeleteBlock) {
1907 // C++11 [expr.delete]p3:
1908 // If the static type of the object to be deleted is different from its
1909 // dynamic type, the static type shall be a base class of the dynamic type
1910 // of the object to be deleted and the static type shall have a virtual
1911 // destructor or the behavior is undefined.
1912 CGF.EmitTypeCheck(TCK: CodeGenFunction::TCK_MemberCall, Loc: DE->getExprLoc(), Addr: Ptr,
1913 Type: ElementType);
1914
1915 const FunctionDecl *OperatorDelete = DE->getOperatorDelete();
1916 assert(!OperatorDelete->isDestroyingOperatorDelete());
1917
1918 // Find the destructor for the type, if applicable. If the
1919 // destructor is virtual, we'll just emit the vcall and return.
1920 const CXXDestructorDecl *Dtor = nullptr;
1921 if (const auto *RD = ElementType->getAsCXXRecordDecl()) {
1922 if (RD->hasDefinition() && !RD->hasTrivialDestructor()) {
1923 Dtor = RD->getDestructor();
1924
1925 if (Dtor->isVirtual()) {
1926 bool UseVirtualCall = true;
1927 const Expr *Base = DE->getArgument();
1928 if (auto *DevirtualizedDtor = dyn_cast_or_null<const CXXDestructorDecl>(
1929 Val: Dtor->getDevirtualizedMethod(
1930 Base, IsAppleKext: CGF.CGM.getLangOpts().AppleKext))) {
1931 UseVirtualCall = false;
1932 const CXXRecordDecl *DevirtualizedClass =
1933 DevirtualizedDtor->getParent();
1934 if (declaresSameEntity(D1: getCXXRecord(E: Base), D2: DevirtualizedClass)) {
1935 // Devirtualized to the class of the base type (the type of the
1936 // whole expression).
1937 Dtor = DevirtualizedDtor;
1938 } else {
1939 // Devirtualized to some other type. Would need to cast the this
1940 // pointer to that type but we don't have support for that yet, so
1941 // do a virtual call. FIXME: handle the case where it is
1942 // devirtualized to the derived type (the type of the inner
1943 // expression) as in EmitCXXMemberOrOperatorMemberCallExpr.
1944 UseVirtualCall = true;
1945 }
1946 }
1947 if (UseVirtualCall) {
1948 CGF.CGM.getCXXABI().emitVirtualObjectDelete(CGF, DE, Ptr, ElementType,
1949 Dtor);
1950 return false;
1951 }
1952 }
1953 }
1954 }
1955
1956 // Make sure that we call delete even if the dtor throws.
1957 // This doesn't have to a conditional cleanup because we're going
1958 // to pop it off in a second.
1959 CGF.EHStack.pushCleanup<CallObjectDelete>(
1960 Kind: NormalAndEHCleanup, A: Ptr.emitRawPointer(CGF), A: OperatorDelete, A: ElementType);
1961
1962 if (Dtor)
1963 CGF.EmitCXXDestructorCall(D: Dtor, Type: Dtor_Complete,
1964 /*ForVirtualBase=*/false,
1965 /*Delegating=*/false, This: Ptr, ThisTy: ElementType);
1966 else if (auto Lifetime = ElementType.getObjCLifetime()) {
1967 switch (Lifetime) {
1968 case Qualifiers::OCL_None:
1969 case Qualifiers::OCL_ExplicitNone:
1970 case Qualifiers::OCL_Autoreleasing:
1971 break;
1972
1973 case Qualifiers::OCL_Strong:
1974 CGF.EmitARCDestroyStrong(addr: Ptr, precise: ARCPreciseLifetime);
1975 break;
1976
1977 case Qualifiers::OCL_Weak:
1978 CGF.EmitARCDestroyWeak(addr: Ptr);
1979 break;
1980 }
1981 }
1982
1983 // When optimizing for size, call 'operator delete' unconditionally.
1984 if (CGF.CGM.getCodeGenOpts().OptimizeSize > 1) {
1985 CGF.EmitBlock(BB: UnconditionalDeleteBlock);
1986 CGF.PopCleanupBlock();
1987 return true;
1988 }
1989
1990 CGF.PopCleanupBlock();
1991 return false;
1992}
1993
1994namespace {
1995/// Calls the given 'operator delete' on an array of objects.
1996struct CallArrayDelete final : EHScopeStack::Cleanup {
1997 llvm::Value *Ptr;
1998 const FunctionDecl *OperatorDelete;
1999 llvm::Value *NumElements;
2000 QualType ElementType;
2001 CharUnits CookieSize;
2002
2003 CallArrayDelete(llvm::Value *Ptr, const FunctionDecl *OperatorDelete,
2004 llvm::Value *NumElements, QualType ElementType,
2005 CharUnits CookieSize)
2006 : Ptr(Ptr), OperatorDelete(OperatorDelete), NumElements(NumElements),
2007 ElementType(ElementType), CookieSize(CookieSize) {}
2008
2009 void Emit(CodeGenFunction &CGF, Flags flags) override {
2010 CGF.EmitDeleteCall(DeleteFD: OperatorDelete, DeletePtr: Ptr, DeleteTy: ElementType, NumElements,
2011 CookieSize);
2012 }
2013};
2014} // namespace
2015
2016/// Emit the code for deleting an array of objects.
2017static void EmitArrayDelete(CodeGenFunction &CGF, const CXXDeleteExpr *E,
2018 Address deletedPtr, QualType elementType) {
2019 llvm::Value *numElements = nullptr;
2020 llvm::Value *allocatedPtr = nullptr;
2021 CharUnits cookieSize;
2022 CGF.CGM.getCXXABI().ReadArrayCookie(CGF, Ptr: deletedPtr, expr: E, ElementType: elementType,
2023 NumElements&: numElements, AllocPtr&: allocatedPtr, CookieSize&: cookieSize);
2024
2025 assert(allocatedPtr && "ReadArrayCookie didn't set allocated pointer");
2026
2027 // Make sure that we call delete even if one of the dtors throws.
2028 const FunctionDecl *operatorDelete = E->getOperatorDelete();
2029 CGF.EHStack.pushCleanup<CallArrayDelete>(Kind: NormalAndEHCleanup, A: allocatedPtr,
2030 A: operatorDelete, A: numElements,
2031 A: elementType, A: cookieSize);
2032
2033 // Destroy the elements.
2034 if (QualType::DestructionKind dtorKind = elementType.isDestructedType()) {
2035 assert(numElements && "no element count for a type with a destructor!");
2036
2037 CharUnits elementSize = CGF.getContext().getTypeSizeInChars(T: elementType);
2038 CharUnits elementAlign =
2039 deletedPtr.getAlignment().alignmentOfArrayElement(elementSize);
2040
2041 llvm::Value *arrayBegin = deletedPtr.emitRawPointer(CGF);
2042 llvm::Value *arrayEnd = CGF.Builder.CreateInBoundsGEP(
2043 Ty: deletedPtr.getElementType(), Ptr: arrayBegin, IdxList: numElements, Name: "delete.end");
2044
2045 // Note that it is legal to allocate a zero-length array, and we
2046 // can never fold the check away because the length should always
2047 // come from a cookie.
2048 CGF.emitArrayDestroy(begin: arrayBegin, end: arrayEnd, elementType, elementAlign,
2049 destroyer: CGF.getDestroyer(destructionKind: dtorKind),
2050 /*checkZeroLength*/ true,
2051 useEHCleanup: CGF.needsEHCleanup(kind: dtorKind));
2052 }
2053
2054 // Pop the cleanup block.
2055 CGF.PopCleanupBlock();
2056}
2057
2058void CodeGenFunction::EmitCXXDeleteExpr(const CXXDeleteExpr *E) {
2059 const Expr *Arg = E->getArgument();
2060 Address Ptr = EmitPointerWithAlignment(Addr: Arg);
2061
2062 // Null check the pointer.
2063 //
2064 // We could avoid this null check if we can determine that the object
2065 // destruction is trivial and doesn't require an array cookie; we can
2066 // unconditionally perform the operator delete call in that case. For now, we
2067 // assume that deleted pointers are null rarely enough that it's better to
2068 // keep the branch. This might be worth revisiting for a -O0 code size win.
2069 llvm::BasicBlock *DeleteNotNull = createBasicBlock(name: "delete.notnull");
2070 llvm::BasicBlock *DeleteEnd = createBasicBlock(name: "delete.end");
2071
2072 llvm::Value *IsNull = Builder.CreateIsNull(Addr: Ptr, Name: "isnull");
2073
2074 Builder.CreateCondBr(Cond: IsNull, True: DeleteEnd, False: DeleteNotNull);
2075 EmitBlock(BB: DeleteNotNull);
2076 Ptr.setKnownNonNull();
2077
2078 QualType DeleteTy = E->getDestroyedType();
2079
2080 // A destroying operator delete overrides the entire operation of the
2081 // delete expression.
2082 if (E->getOperatorDelete()->isDestroyingOperatorDelete()) {
2083 EmitDestroyingObjectDelete(CGF&: *this, DE: E, Ptr, ElementType: DeleteTy);
2084 EmitBlock(BB: DeleteEnd);
2085 return;
2086 }
2087
2088 // We might be deleting a pointer to array.
2089 DeleteTy = getContext().getBaseElementType(QT: DeleteTy);
2090 Ptr = Ptr.withElementType(ElemTy: ConvertTypeForMem(T: DeleteTy));
2091
2092 if (E->isArrayForm() &&
2093 CGM.getContext().getTargetInfo().emitVectorDeletingDtors(
2094 CGM.getContext().getLangOpts())) {
2095 if (auto *RD = DeleteTy->getAsCXXRecordDecl()) {
2096 auto *Dtor = RD->getDestructor();
2097 if (Dtor && Dtor->isVirtual()) {
2098 llvm::Value *NumElements = nullptr;
2099 llvm::Value *AllocatedPtr = nullptr;
2100 CharUnits CookieSize;
2101 llvm::BasicBlock *BodyBB = createBasicBlock(name: "vdtor.call");
2102 llvm::BasicBlock *DoneBB = createBasicBlock(name: "vdtor.nocall");
2103 // Check array cookie to see if the array has length 0. Don't call
2104 // the destructor in that case.
2105 CGM.getCXXABI().ReadArrayCookie(CGF&: *this, Ptr, expr: E, ElementType: DeleteTy, NumElements,
2106 AllocPtr&: AllocatedPtr, CookieSize);
2107
2108 auto *CondTy = cast<llvm::IntegerType>(Val: NumElements->getType());
2109 llvm::Value *IsEmpty = Builder.CreateICmpEQ(
2110 LHS: NumElements, RHS: llvm::ConstantInt::get(Ty: CondTy, V: 0));
2111 Builder.CreateCondBr(Cond: IsEmpty, True: DoneBB, False: BodyBB);
2112
2113 // Delete cookie for empty array.
2114 const FunctionDecl *OperatorDelete = E->getOperatorDelete();
2115 EmitBlock(BB: DoneBB);
2116 EmitDeleteCall(DeleteFD: OperatorDelete, DeletePtr: AllocatedPtr, DeleteTy, NumElements,
2117 CookieSize);
2118 EmitBranch(Block: DeleteEnd);
2119
2120 EmitBlock(BB: BodyBB);
2121 if (!EmitObjectDelete(CGF&: *this, DE: E, Ptr, ElementType: DeleteTy, UnconditionalDeleteBlock: DeleteEnd))
2122 EmitBlock(BB: DeleteEnd);
2123 return;
2124 }
2125 }
2126 }
2127
2128 if (E->isArrayForm()) {
2129 EmitArrayDelete(CGF&: *this, E, deletedPtr: Ptr, elementType: DeleteTy);
2130 EmitBlock(BB: DeleteEnd);
2131 } else {
2132 if (!EmitObjectDelete(CGF&: *this, DE: E, Ptr, ElementType: DeleteTy, UnconditionalDeleteBlock: DeleteEnd))
2133 EmitBlock(BB: DeleteEnd);
2134 }
2135}
2136
2137static llvm::Value *EmitTypeidFromVTable(CodeGenFunction &CGF, const Expr *E,
2138 llvm::Type *StdTypeInfoPtrTy,
2139 bool HasNullCheck) {
2140 // Get the vtable pointer.
2141 Address ThisPtr = CGF.EmitLValue(E).getAddress();
2142
2143 QualType SrcRecordTy = E->getType();
2144
2145 // C++ [class.cdtor]p4:
2146 // If the operand of typeid refers to the object under construction or
2147 // destruction and the static type of the operand is neither the constructor
2148 // or destructor’s class nor one of its bases, the behavior is undefined.
2149 CGF.EmitTypeCheck(TCK: CodeGenFunction::TCK_DynamicOperation, Loc: E->getExprLoc(),
2150 Addr: ThisPtr, Type: SrcRecordTy);
2151
2152 // Whether we need an explicit null pointer check. For example, with the
2153 // Microsoft ABI, if this is a call to __RTtypeid, the null pointer check and
2154 // exception throw is inside the __RTtypeid(nullptr) call
2155 if (HasNullCheck &&
2156 CGF.CGM.getCXXABI().shouldTypeidBeNullChecked(SrcRecordTy)) {
2157 llvm::BasicBlock *BadTypeidBlock =
2158 CGF.createBasicBlock(name: "typeid.bad_typeid");
2159 llvm::BasicBlock *EndBlock = CGF.createBasicBlock(name: "typeid.end");
2160
2161 llvm::Value *IsNull = CGF.Builder.CreateIsNull(Addr: ThisPtr);
2162 CGF.Builder.CreateCondBr(Cond: IsNull, True: BadTypeidBlock, False: EndBlock);
2163
2164 CGF.EmitBlock(BB: BadTypeidBlock);
2165 CGF.CGM.getCXXABI().EmitBadTypeidCall(CGF);
2166 CGF.EmitBlock(BB: EndBlock);
2167 }
2168
2169 return CGF.CGM.getCXXABI().EmitTypeid(CGF, SrcRecordTy, ThisPtr,
2170 StdTypeInfoPtrTy);
2171}
2172
2173llvm::Value *CodeGenFunction::EmitCXXTypeidExpr(const CXXTypeidExpr *E) {
2174 // Ideally, we would like to use GlobalsInt8PtrTy here, however, we cannot,
2175 // primarily because the result of applying typeid is a value of type
2176 // type_info, which is declared & defined by the standard library
2177 // implementation and expects to operate on the generic (default) AS.
2178 // https://reviews.llvm.org/D157452 has more context, and a possible solution.
2179 llvm::Type *PtrTy = Int8PtrTy;
2180 LangAS GlobAS = CGM.GetGlobalVarAddressSpace(D: nullptr);
2181
2182 auto MaybeASCast = [=](auto &&TypeInfo) {
2183 if (GlobAS == LangAS::Default)
2184 return TypeInfo;
2185 return getTargetHooks().performAddrSpaceCast(CGM, TypeInfo, GlobAS, PtrTy);
2186 };
2187
2188 if (E->isTypeOperand()) {
2189 llvm::Constant *TypeInfo =
2190 CGM.GetAddrOfRTTIDescriptor(Ty: E->getTypeOperand(Context: getContext()));
2191 return MaybeASCast(TypeInfo);
2192 }
2193
2194 // C++ [expr.typeid]p2:
2195 // When typeid is applied to a glvalue expression whose type is a
2196 // polymorphic class type, the result refers to a std::type_info object
2197 // representing the type of the most derived object (that is, the dynamic
2198 // type) to which the glvalue refers.
2199 // If the operand is already most derived object, no need to look up vtable.
2200 if (E->isPotentiallyEvaluated() && !E->isMostDerived(Context: getContext()))
2201 return EmitTypeidFromVTable(CGF&: *this, E: E->getExprOperand(), StdTypeInfoPtrTy: PtrTy,
2202 HasNullCheck: E->hasNullCheck());
2203
2204 QualType OperandTy = E->getExprOperand()->getType();
2205 return MaybeASCast(CGM.GetAddrOfRTTIDescriptor(Ty: OperandTy));
2206}
2207
2208static llvm::Value *EmitDynamicCastToNull(CodeGenFunction &CGF,
2209 QualType DestTy) {
2210 llvm::Type *DestLTy = CGF.ConvertType(T: DestTy);
2211 if (DestTy->isPointerType())
2212 return llvm::Constant::getNullValue(Ty: DestLTy);
2213
2214 /// C++ [expr.dynamic.cast]p9:
2215 /// A failed cast to reference type throws std::bad_cast
2216 if (!CGF.CGM.getCXXABI().EmitBadCastCall(CGF))
2217 return nullptr;
2218
2219 CGF.Builder.ClearInsertionPoint();
2220 return llvm::PoisonValue::get(T: DestLTy);
2221}
2222
2223llvm::Value *CodeGenFunction::EmitDynamicCast(Address ThisAddr,
2224 const CXXDynamicCastExpr *DCE) {
2225 CGM.EmitExplicitCastExprType(E: DCE, CGF: this);
2226 QualType DestTy = DCE->getTypeAsWritten();
2227
2228 QualType SrcTy = DCE->getSubExpr()->getType();
2229
2230 // C++ [expr.dynamic.cast]p7:
2231 // If T is "pointer to cv void," then the result is a pointer to the most
2232 // derived object pointed to by v.
2233 bool IsDynamicCastToVoid = DestTy->isVoidPointerType();
2234 QualType SrcRecordTy;
2235 QualType DestRecordTy;
2236 if (IsDynamicCastToVoid) {
2237 SrcRecordTy = SrcTy->getPointeeType();
2238 // No DestRecordTy.
2239 } else if (const PointerType *DestPTy = DestTy->getAs<PointerType>()) {
2240 SrcRecordTy = SrcTy->castAs<PointerType>()->getPointeeType();
2241 DestRecordTy = DestPTy->getPointeeType();
2242 } else {
2243 SrcRecordTy = SrcTy;
2244 DestRecordTy = DestTy->castAs<ReferenceType>()->getPointeeType();
2245 }
2246
2247 // C++ [class.cdtor]p5:
2248 // If the operand of the dynamic_cast refers to the object under
2249 // construction or destruction and the static type of the operand is not a
2250 // pointer to or object of the constructor or destructor’s own class or one
2251 // of its bases, the dynamic_cast results in undefined behavior.
2252 EmitTypeCheck(TCK: TCK_DynamicOperation, Loc: DCE->getExprLoc(), Addr: ThisAddr, Type: SrcRecordTy);
2253
2254 if (DCE->isAlwaysNull()) {
2255 if (llvm::Value *T = EmitDynamicCastToNull(CGF&: *this, DestTy)) {
2256 // Expression emission is expected to retain a valid insertion point.
2257 if (!Builder.GetInsertBlock())
2258 EmitBlock(BB: createBasicBlock(name: "dynamic_cast.unreachable"));
2259 return T;
2260 }
2261 }
2262
2263 assert(SrcRecordTy->isRecordType() && "source type must be a record type!");
2264
2265 // If the destination is effectively final, the cast succeeds if and only
2266 // if the dynamic type of the pointer is exactly the destination type.
2267 bool IsExact = !IsDynamicCastToVoid &&
2268 CGM.getCodeGenOpts().OptimizationLevel > 0 &&
2269 DestRecordTy->getAsCXXRecordDecl()->isEffectivelyFinal() &&
2270 CGM.getCXXABI().shouldEmitExactDynamicCast(DestRecordTy);
2271
2272 std::optional<CGCXXABI::ExactDynamicCastInfo> ExactCastInfo;
2273 if (IsExact) {
2274 ExactCastInfo = CGM.getCXXABI().getExactDynamicCastInfo(SrcRecordTy, DestTy,
2275 DestRecordTy);
2276 if (!ExactCastInfo) {
2277 llvm::Value *NullValue = EmitDynamicCastToNull(CGF&: *this, DestTy);
2278 if (!Builder.GetInsertBlock())
2279 EmitBlock(BB: createBasicBlock(name: "dynamic_cast.unreachable"));
2280 return NullValue;
2281 }
2282 }
2283
2284 // C++ [expr.dynamic.cast]p4:
2285 // If the value of v is a null pointer value in the pointer case, the result
2286 // is the null pointer value of type T.
2287 bool ShouldNullCheckSrcValue =
2288 IsExact || CGM.getCXXABI().shouldDynamicCastCallBeNullChecked(
2289 SrcIsPtr: SrcTy->isPointerType(), SrcRecordTy);
2290
2291 llvm::BasicBlock *CastNull = nullptr;
2292 llvm::BasicBlock *CastNotNull = nullptr;
2293 llvm::BasicBlock *CastEnd = createBasicBlock(name: "dynamic_cast.end");
2294
2295 if (ShouldNullCheckSrcValue) {
2296 CastNull = createBasicBlock(name: "dynamic_cast.null");
2297 CastNotNull = createBasicBlock(name: "dynamic_cast.notnull");
2298
2299 llvm::Value *IsNull = Builder.CreateIsNull(Addr: ThisAddr);
2300 Builder.CreateCondBr(Cond: IsNull, True: CastNull, False: CastNotNull);
2301 EmitBlock(BB: CastNotNull);
2302 }
2303
2304 llvm::Value *Value;
2305 if (IsDynamicCastToVoid) {
2306 Value = CGM.getCXXABI().emitDynamicCastToVoid(CGF&: *this, Value: ThisAddr, SrcRecordTy);
2307 } else if (IsExact) {
2308 // If the destination type is effectively final, this pointer points to the
2309 // right type if and only if its vptr has the right value.
2310 Value = CGM.getCXXABI().emitExactDynamicCast(
2311 CGF&: *this, Value: ThisAddr, SrcRecordTy, DestTy, DestRecordTy, CastInfo: *ExactCastInfo,
2312 CastSuccess: CastEnd, CastFail: CastNull);
2313 } else {
2314 assert(DestRecordTy->isRecordType() &&
2315 "destination type must be a record type!");
2316 Value = CGM.getCXXABI().emitDynamicCastCall(CGF&: *this, Value: ThisAddr, SrcRecordTy,
2317 DestTy, DestRecordTy, CastEnd);
2318 }
2319 CastNotNull = Builder.GetInsertBlock();
2320
2321 llvm::Value *NullValue = nullptr;
2322 if (ShouldNullCheckSrcValue) {
2323 EmitBranch(Block: CastEnd);
2324
2325 EmitBlock(BB: CastNull);
2326 NullValue = EmitDynamicCastToNull(CGF&: *this, DestTy);
2327 CastNull = Builder.GetInsertBlock();
2328
2329 EmitBranch(Block: CastEnd);
2330 }
2331
2332 EmitBlock(BB: CastEnd);
2333
2334 if (CastNull) {
2335 llvm::PHINode *PHI = Builder.CreatePHI(Ty: Value->getType(), NumReservedValues: 2);
2336 PHI->addIncoming(V: Value, BB: CastNotNull);
2337 PHI->addIncoming(V: NullValue, BB: CastNull);
2338
2339 Value = PHI;
2340 }
2341
2342 return Value;
2343}
2344