1 //===--- CGExpr.cpp - Emit LLVM Code from Expressions ---------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This contains code to emit Expr nodes as LLVM code.
12 //===----------------------------------------------------------------------===//
14 #include "CodeGenFunction.h"
17 #include "CGDebugInfo.h"
18 #include "CGObjCRuntime.h"
19 #include "CGRecordLayout.h"
20 #include "CodeGenModule.h"
21 #include "TargetInfo.h"
22 #include "clang/AST/ASTContext.h"
23 #include "clang/AST/DeclObjC.h"
24 #include "clang/Frontend/CodeGenOptions.h"
25 #include "llvm/ADT/Hashing.h"
26 #include "llvm/IR/DataLayout.h"
27 #include "llvm/IR/Intrinsics.h"
28 #include "llvm/IR/LLVMContext.h"
29 #include "llvm/IR/MDBuilder.h"
30 #include "llvm/Support/ConvertUTF.h"
32 using namespace clang;
33 using namespace CodeGen;
35 //===--------------------------------------------------------------------===//
36 // Miscellaneous Helper Methods
37 //===--------------------------------------------------------------------===//
39 llvm::Value *CodeGenFunction::EmitCastToVoidPtr(llvm::Value *value) {
40 unsigned addressSpace =
41 cast<llvm::PointerType>(value->getType())->getAddressSpace();
43 llvm::PointerType *destType = Int8PtrTy;
45 destType = llvm::Type::getInt8PtrTy(getLLVMContext(), addressSpace);
47 if (value->getType() == destType) return value;
48 return Builder.CreateBitCast(value, destType);
51 /// CreateTempAlloca - This creates a alloca and inserts it into the entry
53 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty,
55 if (!Builder.isNamePreserving())
56 return new llvm::AllocaInst(Ty, 0, "", AllocaInsertPt);
57 return new llvm::AllocaInst(Ty, 0, Name, AllocaInsertPt);
60 void CodeGenFunction::InitTempAlloca(llvm::AllocaInst *Var,
62 llvm::StoreInst *Store = new llvm::StoreInst(Init, Var);
63 llvm::BasicBlock *Block = AllocaInsertPt->getParent();
64 Block->getInstList().insertAfter(&*AllocaInsertPt, Store);
67 llvm::AllocaInst *CodeGenFunction::CreateIRTemp(QualType Ty,
69 llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertType(Ty), Name);
70 // FIXME: Should we prefer the preferred type alignment here?
71 CharUnits Align = getContext().getTypeAlignInChars(Ty);
72 Alloc->setAlignment(Align.getQuantity());
76 llvm::AllocaInst *CodeGenFunction::CreateMemTemp(QualType Ty,
78 llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty), Name);
79 // FIXME: Should we prefer the preferred type alignment here?
80 CharUnits Align = getContext().getTypeAlignInChars(Ty);
81 Alloc->setAlignment(Align.getQuantity());
85 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
86 /// expression and compare the result against zero, returning an Int1Ty value.
87 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
88 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) {
89 llvm::Value *MemPtr = EmitScalarExpr(E);
90 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT);
93 QualType BoolTy = getContext().BoolTy;
94 if (!E->getType()->isAnyComplexType())
95 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy);
97 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(),BoolTy);
100 /// EmitIgnoredExpr - Emit code to compute the specified expression,
101 /// ignoring the result.
102 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) {
104 return (void) EmitAnyExpr(E, AggValueSlot::ignored(), true);
106 // Just emit it as an l-value and drop the result.
110 /// EmitAnyExpr - Emit code to compute the specified expression which
111 /// can have any type. The result is returned as an RValue struct.
112 /// If this is an aggregate expression, AggSlot indicates where the
113 /// result should be returned.
114 RValue CodeGenFunction::EmitAnyExpr(const Expr *E,
115 AggValueSlot aggSlot,
117 switch (getEvaluationKind(E->getType())) {
119 return RValue::get(EmitScalarExpr(E, ignoreResult));
121 return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult));
123 if (!ignoreResult && aggSlot.isIgnored())
124 aggSlot = CreateAggTemp(E->getType(), "agg-temp");
125 EmitAggExpr(E, aggSlot);
126 return aggSlot.asRValue();
128 llvm_unreachable("bad evaluation kind");
131 /// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will
132 /// always be accessible even if no aggregate location is provided.
133 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) {
134 AggValueSlot AggSlot = AggValueSlot::ignored();
136 if (hasAggregateEvaluationKind(E->getType()))
137 AggSlot = CreateAggTemp(E->getType(), "agg.tmp");
138 return EmitAnyExpr(E, AggSlot);
141 /// EmitAnyExprToMem - Evaluate an expression into a given memory
143 void CodeGenFunction::EmitAnyExprToMem(const Expr *E,
144 llvm::Value *Location,
147 // FIXME: This function should take an LValue as an argument.
148 switch (getEvaluationKind(E->getType())) {
150 EmitComplexExprIntoLValue(E,
151 MakeNaturalAlignAddrLValue(Location, E->getType()),
155 case TEK_Aggregate: {
156 CharUnits Alignment = getContext().getTypeAlignInChars(E->getType());
157 EmitAggExpr(E, AggValueSlot::forAddr(Location, Alignment, Quals,
158 AggValueSlot::IsDestructed_t(IsInit),
159 AggValueSlot::DoesNotNeedGCBarriers,
160 AggValueSlot::IsAliased_t(!IsInit)));
165 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false));
166 LValue LV = MakeAddrLValue(Location, E->getType());
167 EmitStoreThroughLValue(RV, LV);
171 llvm_unreachable("bad evaluation kind");
175 pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M,
176 const Expr *E, llvm::Value *ReferenceTemporary) {
177 // Objective-C++ ARC:
178 // If we are binding a reference to a temporary that has ownership, we
179 // need to perform retain/release operations on the temporary.
181 // FIXME: This should be looking at E, not M.
182 if (CGF.getLangOpts().ObjCAutoRefCount &&
183 M->getType()->isObjCLifetimeType()) {
184 QualType ObjCARCReferenceLifetimeType = M->getType();
185 switch (Qualifiers::ObjCLifetime Lifetime =
186 ObjCARCReferenceLifetimeType.getObjCLifetime()) {
187 case Qualifiers::OCL_None:
188 case Qualifiers::OCL_ExplicitNone:
189 // Carry on to normal cleanup handling.
192 case Qualifiers::OCL_Autoreleasing:
193 // Nothing to do; cleaned up by an autorelease pool.
196 case Qualifiers::OCL_Strong:
197 case Qualifiers::OCL_Weak:
198 switch (StorageDuration Duration = M->getStorageDuration()) {
200 // Note: we intentionally do not register a cleanup to release
201 // the object on program termination.
205 // FIXME: We should probably register a cleanup in this case.
209 case SD_FullExpression:
210 assert(!ObjCARCReferenceLifetimeType->isArrayType());
211 CodeGenFunction::Destroyer *Destroy;
212 CleanupKind CleanupKind;
213 if (Lifetime == Qualifiers::OCL_Strong) {
214 const ValueDecl *VD = M->getExtendingDecl();
216 VD && isa<VarDecl>(VD) && VD->hasAttr<ObjCPreciseLifetimeAttr>();
217 CleanupKind = CGF.getARCCleanupKind();
218 Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise
219 : &CodeGenFunction::destroyARCStrongImprecise;
221 // __weak objects always get EH cleanups; otherwise, exceptions
222 // could cause really nasty crashes instead of mere leaks.
223 CleanupKind = NormalAndEHCleanup;
224 Destroy = &CodeGenFunction::destroyARCWeak;
226 if (Duration == SD_FullExpression)
227 CGF.pushDestroy(CleanupKind, ReferenceTemporary,
228 ObjCARCReferenceLifetimeType, *Destroy,
229 CleanupKind & EHCleanup);
231 CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary,
232 ObjCARCReferenceLifetimeType,
233 *Destroy, CleanupKind & EHCleanup);
237 llvm_unreachable("temporary cannot have dynamic storage duration");
239 llvm_unreachable("unknown storage duration");
243 CXXDestructorDecl *ReferenceTemporaryDtor = 0;
244 if (const RecordType *RT =
245 E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
246 // Get the destructor for the reference temporary.
247 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
248 if (!ClassDecl->hasTrivialDestructor())
249 ReferenceTemporaryDtor = ClassDecl->getDestructor();
252 if (!ReferenceTemporaryDtor)
255 // Call the destructor for the temporary.
256 switch (M->getStorageDuration()) {
259 llvm::Constant *CleanupFn;
260 llvm::Constant *CleanupArg;
261 if (E->getType()->isArrayType()) {
262 CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper(
263 cast<llvm::Constant>(ReferenceTemporary), E->getType(),
264 CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions,
265 dyn_cast_or_null<VarDecl>(M->getExtendingDecl()));
266 CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy);
269 CGF.CGM.GetAddrOfCXXDestructor(ReferenceTemporaryDtor, Dtor_Complete);
270 CleanupArg = cast<llvm::Constant>(ReferenceTemporary);
272 CGF.CGM.getCXXABI().registerGlobalDtor(
273 CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg);
277 case SD_FullExpression:
278 CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(),
279 CodeGenFunction::destroyCXXObject,
280 CGF.getLangOpts().Exceptions);
284 CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup,
285 ReferenceTemporary, E->getType(),
286 CodeGenFunction::destroyCXXObject,
287 CGF.getLangOpts().Exceptions);
291 llvm_unreachable("temporary cannot have dynamic storage duration");
296 createReferenceTemporary(CodeGenFunction &CGF,
297 const MaterializeTemporaryExpr *M, const Expr *Inner) {
298 switch (M->getStorageDuration()) {
299 case SD_FullExpression:
301 return CGF.CreateMemTemp(Inner->getType(), "ref.tmp");
305 return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner);
308 llvm_unreachable("temporary can't have dynamic storage duration");
310 llvm_unreachable("unknown storage duration");
313 LValue CodeGenFunction::EmitMaterializeTemporaryExpr(
314 const MaterializeTemporaryExpr *M) {
315 const Expr *E = M->GetTemporaryExpr();
317 if (getLangOpts().ObjCAutoRefCount &&
318 M->getType()->isObjCLifetimeType() &&
319 M->getType().getObjCLifetime() != Qualifiers::OCL_None &&
320 M->getType().getObjCLifetime() != Qualifiers::OCL_ExplicitNone) {
321 // FIXME: Fold this into the general case below.
322 llvm::Value *Object = createReferenceTemporary(*this, M, E);
323 LValue RefTempDst = MakeAddrLValue(Object, M->getType());
325 if (llvm::GlobalVariable *Var = dyn_cast<llvm::GlobalVariable>(Object)) {
326 // We should not have emitted the initializer for this temporary as a
328 assert(!Var->hasInitializer());
329 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
332 EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false);
334 pushTemporaryCleanup(*this, M, E, Object);
338 SmallVector<const Expr *, 2> CommaLHSs;
339 SmallVector<SubobjectAdjustment, 2> Adjustments;
340 E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
342 for (unsigned I = 0, N = CommaLHSs.size(); I != N; ++I)
343 EmitIgnoredExpr(CommaLHSs[I]);
345 if (const OpaqueValueExpr *opaque = dyn_cast<OpaqueValueExpr>(E)) {
346 if (opaque->getType()->isRecordType()) {
347 assert(Adjustments.empty());
348 return EmitOpaqueValueLValue(opaque);
352 // Create and initialize the reference temporary.
353 llvm::Value *Object = createReferenceTemporary(*this, M, E);
354 if (llvm::GlobalVariable *Var = dyn_cast<llvm::GlobalVariable>(Object)) {
355 // If the temporary is a global and has a constant initializer, we may
356 // have already initialized it.
357 if (!Var->hasInitializer()) {
358 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
359 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
362 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
364 pushTemporaryCleanup(*this, M, E, Object);
366 // Perform derived-to-base casts and/or field accesses, to get from the
367 // temporary object we created (and, potentially, for which we extended
368 // the lifetime) to the subobject we're binding the reference to.
369 for (unsigned I = Adjustments.size(); I != 0; --I) {
370 SubobjectAdjustment &Adjustment = Adjustments[I-1];
371 switch (Adjustment.Kind) {
372 case SubobjectAdjustment::DerivedToBaseAdjustment:
374 GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass,
375 Adjustment.DerivedToBase.BasePath->path_begin(),
376 Adjustment.DerivedToBase.BasePath->path_end(),
377 /*NullCheckValue=*/ false);
380 case SubobjectAdjustment::FieldAdjustment: {
381 LValue LV = MakeAddrLValue(Object, E->getType());
382 LV = EmitLValueForField(LV, Adjustment.Field);
383 assert(LV.isSimple() &&
384 "materialized temporary field is not a simple lvalue");
385 Object = LV.getAddress();
389 case SubobjectAdjustment::MemberPointerAdjustment: {
390 llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS);
391 Object = CGM.getCXXABI().EmitMemberDataPointerAddress(
392 *this, Object, Ptr, Adjustment.Ptr.MPT);
398 return MakeAddrLValue(Object, M->getType());
402 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) {
403 // Emit the expression as an lvalue.
404 LValue LV = EmitLValue(E);
405 assert(LV.isSimple());
406 llvm::Value *Value = LV.getAddress();
408 if (SanitizePerformTypeCheck && !E->getType()->isFunctionType()) {
409 // C++11 [dcl.ref]p5 (as amended by core issue 453):
410 // If a glvalue to which a reference is directly bound designates neither
411 // an existing object or function of an appropriate type nor a region of
412 // storage of suitable size and alignment to contain an object of the
413 // reference's type, the behavior is undefined.
414 QualType Ty = E->getType();
415 EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty);
418 return RValue::get(Value);
422 /// getAccessedFieldNo - Given an encoded value and a result number, return the
423 /// input field number being accessed.
424 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
425 const llvm::Constant *Elts) {
426 return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx))
430 /// Emit the hash_16_bytes function from include/llvm/ADT/Hashing.h.
431 static llvm::Value *emitHash16Bytes(CGBuilderTy &Builder, llvm::Value *Low,
433 llvm::Value *KMul = Builder.getInt64(0x9ddfea08eb382d69ULL);
434 llvm::Value *K47 = Builder.getInt64(47);
435 llvm::Value *A0 = Builder.CreateMul(Builder.CreateXor(Low, High), KMul);
436 llvm::Value *A1 = Builder.CreateXor(Builder.CreateLShr(A0, K47), A0);
437 llvm::Value *B0 = Builder.CreateMul(Builder.CreateXor(High, A1), KMul);
438 llvm::Value *B1 = Builder.CreateXor(Builder.CreateLShr(B0, K47), B0);
439 return Builder.CreateMul(B1, KMul);
442 void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc,
443 llvm::Value *Address,
444 QualType Ty, CharUnits Alignment) {
445 if (!SanitizePerformTypeCheck)
448 // Don't check pointers outside the default address space. The null check
449 // isn't correct, the object-size check isn't supported by LLVM, and we can't
450 // communicate the addresses to the runtime handler for the vptr check.
451 if (Address->getType()->getPointerAddressSpace())
454 llvm::Value *Cond = 0;
455 llvm::BasicBlock *Done = 0;
458 // The glvalue must not be an empty glvalue.
459 Cond = Builder.CreateICmpNE(
460 Address, llvm::Constant::getNullValue(Address->getType()));
462 if (TCK == TCK_DowncastPointer) {
463 // When performing a pointer downcast, it's OK if the value is null.
464 // Skip the remaining checks in that case.
465 Done = createBasicBlock("null");
466 llvm::BasicBlock *Rest = createBasicBlock("not.null");
467 Builder.CreateCondBr(Cond, Rest, Done);
473 if (SanOpts->ObjectSize && !Ty->isIncompleteType()) {
474 uint64_t Size = getContext().getTypeSizeInChars(Ty).getQuantity();
476 // The glvalue must refer to a large enough storage region.
477 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation
479 // FIXME: Get object address space
480 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
481 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
482 llvm::Value *Min = Builder.getFalse();
483 llvm::Value *CastAddr = Builder.CreateBitCast(Address, Int8PtrTy);
484 llvm::Value *LargeEnough =
485 Builder.CreateICmpUGE(Builder.CreateCall2(F, CastAddr, Min),
486 llvm::ConstantInt::get(IntPtrTy, Size));
487 Cond = Cond ? Builder.CreateAnd(Cond, LargeEnough) : LargeEnough;
490 uint64_t AlignVal = 0;
492 if (SanOpts->Alignment) {
493 AlignVal = Alignment.getQuantity();
494 if (!Ty->isIncompleteType() && !AlignVal)
495 AlignVal = getContext().getTypeAlignInChars(Ty).getQuantity();
497 // The glvalue must be suitably aligned.
500 Builder.CreateAnd(Builder.CreatePtrToInt(Address, IntPtrTy),
501 llvm::ConstantInt::get(IntPtrTy, AlignVal - 1));
502 llvm::Value *Aligned =
503 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0));
504 Cond = Cond ? Builder.CreateAnd(Cond, Aligned) : Aligned;
509 llvm::Constant *StaticData[] = {
510 EmitCheckSourceLocation(Loc),
511 EmitCheckTypeDescriptor(Ty),
512 llvm::ConstantInt::get(SizeTy, AlignVal),
513 llvm::ConstantInt::get(Int8Ty, TCK)
515 EmitCheck(Cond, "type_mismatch", StaticData, Address, CRK_Recoverable);
518 // If possible, check that the vptr indicates that there is a subobject of
519 // type Ty at offset zero within this object.
521 // C++11 [basic.life]p5,6:
522 // [For storage which does not refer to an object within its lifetime]
523 // The program has undefined behavior if:
524 // -- the [pointer or glvalue] is used to access a non-static data member
525 // or call a non-static member function
526 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
528 (TCK == TCK_MemberAccess || TCK == TCK_MemberCall ||
529 TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference) &&
530 RD && RD->hasDefinition() && RD->isDynamicClass()) {
531 // Compute a hash of the mangled name of the type.
533 // FIXME: This is not guaranteed to be deterministic! Move to a
534 // fingerprinting mechanism once LLVM provides one. For the time
535 // being the implementation happens to be deterministic.
536 SmallString<64> MangledName;
537 llvm::raw_svector_ostream Out(MangledName);
538 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(),
540 llvm::hash_code TypeHash = hash_value(Out.str());
542 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr).
543 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash);
544 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0);
545 llvm::Value *VPtrAddr = Builder.CreateBitCast(Address, VPtrTy);
546 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr);
547 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty);
549 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High);
550 Hash = Builder.CreateTrunc(Hash, IntPtrTy);
552 // Look the hash up in our cache.
553 const int CacheSize = 128;
554 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize);
555 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable,
556 "__ubsan_vptr_type_cache");
557 llvm::Value *Slot = Builder.CreateAnd(Hash,
558 llvm::ConstantInt::get(IntPtrTy,
560 llvm::Value *Indices[] = { Builder.getInt32(0), Slot };
561 llvm::Value *CacheVal =
562 Builder.CreateLoad(Builder.CreateInBoundsGEP(Cache, Indices));
564 // If the hash isn't in the cache, call a runtime handler to perform the
565 // hard work of checking whether the vptr is for an object of the right
566 // type. This will either fill in the cache and return, or produce a
568 llvm::Constant *StaticData[] = {
569 EmitCheckSourceLocation(Loc),
570 EmitCheckTypeDescriptor(Ty),
571 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()),
572 llvm::ConstantInt::get(Int8Ty, TCK)
574 llvm::Value *DynamicData[] = { Address, Hash };
575 EmitCheck(Builder.CreateICmpEQ(CacheVal, Hash),
576 "dynamic_type_cache_miss", StaticData, DynamicData,
577 CRK_AlwaysRecoverable);
581 Builder.CreateBr(Done);
586 /// Determine whether this expression refers to a flexible array member in a
587 /// struct. We disable array bounds checks for such members.
588 static bool isFlexibleArrayMemberExpr(const Expr *E) {
589 // For compatibility with existing code, we treat arrays of length 0 or
590 // 1 as flexible array members.
591 const ArrayType *AT = E->getType()->castAsArrayTypeUnsafe();
592 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT)) {
593 if (CAT->getSize().ugt(1))
595 } else if (!isa<IncompleteArrayType>(AT))
598 E = E->IgnoreParens();
600 // A flexible array member must be the last member in the class.
601 if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
602 // FIXME: If the base type of the member expr is not FD->getParent(),
603 // this should not be treated as a flexible array member access.
604 if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
605 RecordDecl::field_iterator FI(
606 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
607 return ++FI == FD->getParent()->field_end();
614 /// If Base is known to point to the start of an array, return the length of
615 /// that array. Return 0 if the length cannot be determined.
616 static llvm::Value *getArrayIndexingBound(
617 CodeGenFunction &CGF, const Expr *Base, QualType &IndexedType) {
618 // For the vector indexing extension, the bound is the number of elements.
619 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) {
620 IndexedType = Base->getType();
621 return CGF.Builder.getInt32(VT->getNumElements());
624 Base = Base->IgnoreParens();
626 if (const CastExpr *CE = dyn_cast<CastExpr>(Base)) {
627 if (CE->getCastKind() == CK_ArrayToPointerDecay &&
628 !isFlexibleArrayMemberExpr(CE->getSubExpr())) {
629 IndexedType = CE->getSubExpr()->getType();
630 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe();
631 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
632 return CGF.Builder.getInt(CAT->getSize());
633 else if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(AT))
634 return CGF.getVLASize(VAT).first;
641 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
642 llvm::Value *Index, QualType IndexType,
644 assert(SanOpts->ArrayBounds &&
645 "should not be called unless adding bounds checks");
647 QualType IndexedType;
648 llvm::Value *Bound = getArrayIndexingBound(*this, Base, IndexedType);
652 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType();
653 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned);
654 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false);
656 llvm::Constant *StaticData[] = {
657 EmitCheckSourceLocation(E->getExprLoc()),
658 EmitCheckTypeDescriptor(IndexedType),
659 EmitCheckTypeDescriptor(IndexType)
661 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal)
662 : Builder.CreateICmpULE(IndexVal, BoundVal);
663 EmitCheck(Check, "out_of_bounds", StaticData, Index, CRK_Recoverable);
667 CodeGenFunction::ComplexPairTy CodeGenFunction::
668 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
669 bool isInc, bool isPre) {
670 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc());
672 llvm::Value *NextVal;
673 if (isa<llvm::IntegerType>(InVal.first->getType())) {
674 uint64_t AmountVal = isInc ? 1 : -1;
675 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
677 // Add the inc/dec to the real part.
678 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
680 QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
681 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
684 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
686 // Add the inc/dec to the real part.
687 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
690 ComplexPairTy IncVal(NextVal, InVal.second);
692 // Store the updated result through the lvalue.
693 EmitStoreOfComplex(IncVal, LV, /*init*/ false);
695 // If this is a postinc, return the value read from memory, otherwise use the
697 return isPre ? IncVal : InVal;
701 //===----------------------------------------------------------------------===//
702 // LValue Expression Emission
703 //===----------------------------------------------------------------------===//
705 RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
706 if (Ty->isVoidType())
707 return RValue::get(0);
709 switch (getEvaluationKind(Ty)) {
712 ConvertType(Ty->castAs<ComplexType>()->getElementType());
713 llvm::Value *U = llvm::UndefValue::get(EltTy);
714 return RValue::getComplex(std::make_pair(U, U));
717 // If this is a use of an undefined aggregate type, the aggregate must have an
718 // identifiable address. Just because the contents of the value are undefined
719 // doesn't mean that the address can't be taken and compared.
720 case TEK_Aggregate: {
721 llvm::Value *DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
722 return RValue::getAggregate(DestPtr);
726 return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
728 llvm_unreachable("bad evaluation kind");
731 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
733 ErrorUnsupported(E, Name);
734 return GetUndefRValue(E->getType());
737 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
739 ErrorUnsupported(E, Name);
740 llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
741 return MakeAddrLValue(llvm::UndefValue::get(Ty), E->getType());
744 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
746 if (SanOpts->ArrayBounds && isa<ArraySubscriptExpr>(E))
747 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true);
750 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple())
751 EmitTypeCheck(TCK, E->getExprLoc(), LV.getAddress(),
752 E->getType(), LV.getAlignment());
756 /// EmitLValue - Emit code to compute a designator that specifies the location
757 /// of the expression.
759 /// This can return one of two things: a simple address or a bitfield reference.
760 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be
761 /// an LLVM pointer type.
763 /// If this returns a bitfield reference, nothing about the pointee type of the
764 /// LLVM value is known: For example, it may not be a pointer to an integer.
766 /// If this returns a normal address, and if the lvalue's C type is fixed size,
767 /// this method guarantees that the returned pointer type will point to an LLVM
768 /// type of the same size of the lvalue's type. If the lvalue has a variable
769 /// length type, this is not possible.
771 LValue CodeGenFunction::EmitLValue(const Expr *E) {
772 switch (E->getStmtClass()) {
773 default: return EmitUnsupportedLValue(E, "l-value expression");
775 case Expr::ObjCPropertyRefExprClass:
776 llvm_unreachable("cannot emit a property reference directly");
778 case Expr::ObjCSelectorExprClass:
779 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
780 case Expr::ObjCIsaExprClass:
781 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
782 case Expr::BinaryOperatorClass:
783 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
784 case Expr::CompoundAssignOperatorClass:
785 if (!E->getType()->isAnyComplexType())
786 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
787 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
788 case Expr::CallExprClass:
789 case Expr::CXXMemberCallExprClass:
790 case Expr::CXXOperatorCallExprClass:
791 case Expr::UserDefinedLiteralClass:
792 return EmitCallExprLValue(cast<CallExpr>(E));
793 case Expr::VAArgExprClass:
794 return EmitVAArgExprLValue(cast<VAArgExpr>(E));
795 case Expr::DeclRefExprClass:
796 return EmitDeclRefLValue(cast<DeclRefExpr>(E));
797 case Expr::ParenExprClass:
798 return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
799 case Expr::GenericSelectionExprClass:
800 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr());
801 case Expr::PredefinedExprClass:
802 return EmitPredefinedLValue(cast<PredefinedExpr>(E));
803 case Expr::StringLiteralClass:
804 return EmitStringLiteralLValue(cast<StringLiteral>(E));
805 case Expr::ObjCEncodeExprClass:
806 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
807 case Expr::PseudoObjectExprClass:
808 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E));
809 case Expr::InitListExprClass:
810 return EmitInitListLValue(cast<InitListExpr>(E));
811 case Expr::CXXTemporaryObjectExprClass:
812 case Expr::CXXConstructExprClass:
813 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
814 case Expr::CXXBindTemporaryExprClass:
815 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
816 case Expr::CXXUuidofExprClass:
817 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E));
818 case Expr::LambdaExprClass:
819 return EmitLambdaLValue(cast<LambdaExpr>(E));
821 case Expr::ExprWithCleanupsClass: {
822 const ExprWithCleanups *cleanups = cast<ExprWithCleanups>(E);
823 enterFullExpression(cleanups);
824 RunCleanupsScope Scope(*this);
825 return EmitLValue(cleanups->getSubExpr());
828 case Expr::CXXDefaultArgExprClass:
829 return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
830 case Expr::CXXDefaultInitExprClass: {
831 CXXDefaultInitExprScope Scope(*this);
832 return EmitLValue(cast<CXXDefaultInitExpr>(E)->getExpr());
834 case Expr::CXXTypeidExprClass:
835 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
837 case Expr::ObjCMessageExprClass:
838 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
839 case Expr::ObjCIvarRefExprClass:
840 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
841 case Expr::StmtExprClass:
842 return EmitStmtExprLValue(cast<StmtExpr>(E));
843 case Expr::UnaryOperatorClass:
844 return EmitUnaryOpLValue(cast<UnaryOperator>(E));
845 case Expr::ArraySubscriptExprClass:
846 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
847 case Expr::ExtVectorElementExprClass:
848 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
849 case Expr::MemberExprClass:
850 return EmitMemberExpr(cast<MemberExpr>(E));
851 case Expr::CompoundLiteralExprClass:
852 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
853 case Expr::ConditionalOperatorClass:
854 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
855 case Expr::BinaryConditionalOperatorClass:
856 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
857 case Expr::ChooseExprClass:
858 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr());
859 case Expr::OpaqueValueExprClass:
860 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
861 case Expr::SubstNonTypeTemplateParmExprClass:
862 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement());
863 case Expr::ImplicitCastExprClass:
864 case Expr::CStyleCastExprClass:
865 case Expr::CXXFunctionalCastExprClass:
866 case Expr::CXXStaticCastExprClass:
867 case Expr::CXXDynamicCastExprClass:
868 case Expr::CXXReinterpretCastExprClass:
869 case Expr::CXXConstCastExprClass:
870 case Expr::ObjCBridgedCastExprClass:
871 return EmitCastLValue(cast<CastExpr>(E));
873 case Expr::MaterializeTemporaryExprClass:
874 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E));
878 /// Given an object of the given canonical type, can we safely copy a
879 /// value out of it based on its initializer?
880 static bool isConstantEmittableObjectType(QualType type) {
881 assert(type.isCanonical());
882 assert(!type->isReferenceType());
884 // Must be const-qualified but non-volatile.
885 Qualifiers qs = type.getLocalQualifiers();
886 if (!qs.hasConst() || qs.hasVolatile()) return false;
888 // Otherwise, all object types satisfy this except C++ classes with
889 // mutable subobjects or non-trivial copy/destroy behavior.
890 if (const RecordType *RT = dyn_cast<RecordType>(type))
891 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
892 if (RD->hasMutableFields() || !RD->isTrivial())
898 /// Can we constant-emit a load of a reference to a variable of the
899 /// given type? This is different from predicates like
900 /// Decl::isUsableInConstantExpressions because we do want it to apply
901 /// in situations that don't necessarily satisfy the language's rules
902 /// for this (e.g. C++'s ODR-use rules). For example, we want to able
903 /// to do this with const float variables even if those variables
904 /// aren't marked 'constexpr'.
905 enum ConstantEmissionKind {
908 CEK_AsValueOrReference,
911 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) {
912 type = type.getCanonicalType();
913 if (const ReferenceType *ref = dyn_cast<ReferenceType>(type)) {
914 if (isConstantEmittableObjectType(ref->getPointeeType()))
915 return CEK_AsValueOrReference;
916 return CEK_AsReferenceOnly;
918 if (isConstantEmittableObjectType(type))
919 return CEK_AsValueOnly;
923 /// Try to emit a reference to the given value without producing it as
924 /// an l-value. This is actually more than an optimization: we can't
925 /// produce an l-value for variables that we never actually captured
926 /// in a block or lambda, which means const int variables or constexpr
927 /// literals or similar.
928 CodeGenFunction::ConstantEmission
929 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) {
930 ValueDecl *value = refExpr->getDecl();
932 // The value needs to be an enum constant or a constant variable.
933 ConstantEmissionKind CEK;
934 if (isa<ParmVarDecl>(value)) {
936 } else if (VarDecl *var = dyn_cast<VarDecl>(value)) {
937 CEK = checkVarTypeForConstantEmission(var->getType());
938 } else if (isa<EnumConstantDecl>(value)) {
939 CEK = CEK_AsValueOnly;
943 if (CEK == CEK_None) return ConstantEmission();
945 Expr::EvalResult result;
946 bool resultIsReference;
949 // It's best to evaluate all the way as an r-value if that's permitted.
950 if (CEK != CEK_AsReferenceOnly &&
951 refExpr->EvaluateAsRValue(result, getContext())) {
952 resultIsReference = false;
953 resultType = refExpr->getType();
955 // Otherwise, try to evaluate as an l-value.
956 } else if (CEK != CEK_AsValueOnly &&
957 refExpr->EvaluateAsLValue(result, getContext())) {
958 resultIsReference = true;
959 resultType = value->getType();
963 return ConstantEmission();
966 // In any case, if the initializer has side-effects, abandon ship.
967 if (result.HasSideEffects)
968 return ConstantEmission();
970 // Emit as a constant.
971 llvm::Constant *C = CGM.EmitConstantValue(result.Val, resultType, this);
973 // Make sure we emit a debug reference to the global variable.
974 // This should probably fire even for
975 if (isa<VarDecl>(value)) {
976 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value)))
977 EmitDeclRefExprDbgValue(refExpr, C);
979 assert(isa<EnumConstantDecl>(value));
980 EmitDeclRefExprDbgValue(refExpr, C);
983 // If we emitted a reference constant, we need to dereference that.
984 if (resultIsReference)
985 return ConstantEmission::forReference(C);
987 return ConstantEmission::forValue(C);
990 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue,
991 SourceLocation Loc) {
992 return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(),
993 lvalue.getAlignment().getQuantity(),
994 lvalue.getType(), Loc, lvalue.getTBAAInfo(),
995 lvalue.getTBAABaseType(), lvalue.getTBAAOffset());
998 static bool hasBooleanRepresentation(QualType Ty) {
999 if (Ty->isBooleanType())
1002 if (const EnumType *ET = Ty->getAs<EnumType>())
1003 return ET->getDecl()->getIntegerType()->isBooleanType();
1005 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1006 return hasBooleanRepresentation(AT->getValueType());
1011 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
1012 llvm::APInt &Min, llvm::APInt &End,
1014 const EnumType *ET = Ty->getAs<EnumType>();
1015 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
1016 ET && !ET->getDecl()->isFixed();
1017 bool IsBool = hasBooleanRepresentation(Ty);
1018 if (!IsBool && !IsRegularCPlusPlusEnum)
1022 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0);
1023 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2);
1025 const EnumDecl *ED = ET->getDecl();
1026 llvm::Type *LTy = CGF.ConvertTypeForMem(ED->getIntegerType());
1027 unsigned Bitwidth = LTy->getScalarSizeInBits();
1028 unsigned NumNegativeBits = ED->getNumNegativeBits();
1029 unsigned NumPositiveBits = ED->getNumPositiveBits();
1031 if (NumNegativeBits) {
1032 unsigned NumBits = std::max(NumNegativeBits, NumPositiveBits + 1);
1033 assert(NumBits <= Bitwidth);
1034 End = llvm::APInt(Bitwidth, 1) << (NumBits - 1);
1037 assert(NumPositiveBits <= Bitwidth);
1038 End = llvm::APInt(Bitwidth, 1) << NumPositiveBits;
1039 Min = llvm::APInt(Bitwidth, 0);
1045 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
1046 llvm::APInt Min, End;
1047 if (!getRangeForType(*this, Ty, Min, End,
1048 CGM.getCodeGenOpts().StrictEnums))
1051 llvm::MDBuilder MDHelper(getLLVMContext());
1052 return MDHelper.createRange(Min, End);
1055 llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
1056 unsigned Alignment, QualType Ty,
1058 llvm::MDNode *TBAAInfo,
1059 QualType TBAABaseType,
1060 uint64_t TBAAOffset) {
1061 // For better performance, handle vector loads differently.
1062 if (Ty->isVectorType()) {
1064 const llvm::Type *EltTy =
1065 cast<llvm::PointerType>(Addr->getType())->getElementType();
1067 const llvm::VectorType *VTy = cast<llvm::VectorType>(EltTy);
1069 // Handle vectors of size 3, like size 4 for better performance.
1070 if (VTy->getNumElements() == 3) {
1072 // Bitcast to vec4 type.
1073 llvm::VectorType *vec4Ty = llvm::VectorType::get(VTy->getElementType(),
1075 llvm::PointerType *ptVec4Ty =
1076 llvm::PointerType::get(vec4Ty,
1077 (cast<llvm::PointerType>(
1078 Addr->getType()))->getAddressSpace());
1079 llvm::Value *Cast = Builder.CreateBitCast(Addr, ptVec4Ty,
1082 llvm::Value *LoadVal = Builder.CreateLoad(Cast, Volatile, "loadVec4");
1084 // Shuffle vector to get vec3.
1085 llvm::Constant *Mask[] = {
1086 llvm::ConstantInt::get(llvm::Type::getInt32Ty(getLLVMContext()), 0),
1087 llvm::ConstantInt::get(llvm::Type::getInt32Ty(getLLVMContext()), 1),
1088 llvm::ConstantInt::get(llvm::Type::getInt32Ty(getLLVMContext()), 2)
1091 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1092 V = Builder.CreateShuffleVector(LoadVal,
1093 llvm::UndefValue::get(vec4Ty),
1094 MaskV, "extractVec");
1095 return EmitFromMemory(V, Ty);
1099 // Atomic operations have to be done on integral types.
1100 if (Ty->isAtomicType()) {
1101 LValue lvalue = LValue::MakeAddr(Addr, Ty,
1102 CharUnits::fromQuantity(Alignment),
1103 getContext(), TBAAInfo);
1104 return EmitAtomicLoad(lvalue, Loc).getScalarVal();
1107 llvm::LoadInst *Load = Builder.CreateLoad(Addr);
1109 Load->setVolatile(true);
1111 Load->setAlignment(Alignment);
1113 llvm::MDNode *TBAAPath = CGM.getTBAAStructTagInfo(TBAABaseType, TBAAInfo,
1116 CGM.DecorateInstruction(Load, TBAAPath, false/*ConvertTypeToTag*/);
1119 if ((SanOpts->Bool && hasBooleanRepresentation(Ty)) ||
1120 (SanOpts->Enum && Ty->getAs<EnumType>())) {
1121 llvm::APInt Min, End;
1122 if (getRangeForType(*this, Ty, Min, End, true)) {
1126 Check = Builder.CreateICmpULE(
1127 Load, llvm::ConstantInt::get(getLLVMContext(), End));
1129 llvm::Value *Upper = Builder.CreateICmpSLE(
1130 Load, llvm::ConstantInt::get(getLLVMContext(), End));
1131 llvm::Value *Lower = Builder.CreateICmpSGE(
1132 Load, llvm::ConstantInt::get(getLLVMContext(), Min));
1133 Check = Builder.CreateAnd(Upper, Lower);
1135 llvm::Constant *StaticArgs[] = {
1136 EmitCheckSourceLocation(Loc),
1137 EmitCheckTypeDescriptor(Ty)
1139 EmitCheck(Check, "load_invalid_value", StaticArgs, EmitCheckValue(Load),
1142 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
1143 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty))
1144 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
1146 return EmitFromMemory(Load, Ty);
1149 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
1150 // Bool has a different representation in memory than in registers.
1151 if (hasBooleanRepresentation(Ty)) {
1152 // This should really always be an i1, but sometimes it's already
1153 // an i8, and it's awkward to track those cases down.
1154 if (Value->getType()->isIntegerTy(1))
1155 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool");
1156 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1157 "wrong value rep of bool");
1163 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
1164 // Bool has a different representation in memory than in registers.
1165 if (hasBooleanRepresentation(Ty)) {
1166 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1167 "wrong value rep of bool");
1168 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
1174 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr,
1175 bool Volatile, unsigned Alignment,
1176 QualType Ty, llvm::MDNode *TBAAInfo,
1177 bool isInit, QualType TBAABaseType,
1178 uint64_t TBAAOffset) {
1180 // Handle vectors differently to get better performance.
1181 if (Ty->isVectorType()) {
1182 llvm::Type *SrcTy = Value->getType();
1183 llvm::VectorType *VecTy = cast<llvm::VectorType>(SrcTy);
1184 // Handle vec3 special.
1185 if (VecTy->getNumElements() == 3) {
1186 llvm::LLVMContext &VMContext = getLLVMContext();
1188 // Our source is a vec3, do a shuffle vector to make it a vec4.
1189 SmallVector<llvm::Constant*, 4> Mask;
1190 Mask.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
1192 Mask.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
1194 Mask.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
1196 Mask.push_back(llvm::UndefValue::get(llvm::Type::getInt32Ty(VMContext)));
1198 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1199 Value = Builder.CreateShuffleVector(Value,
1200 llvm::UndefValue::get(VecTy),
1201 MaskV, "extractVec");
1202 SrcTy = llvm::VectorType::get(VecTy->getElementType(), 4);
1204 llvm::PointerType *DstPtr = cast<llvm::PointerType>(Addr->getType());
1205 if (DstPtr->getElementType() != SrcTy) {
1207 llvm::PointerType::get(SrcTy, DstPtr->getAddressSpace());
1208 Addr = Builder.CreateBitCast(Addr, MemTy, "storetmp");
1212 Value = EmitToMemory(Value, Ty);
1214 if (Ty->isAtomicType()) {
1215 EmitAtomicStore(RValue::get(Value),
1216 LValue::MakeAddr(Addr, Ty,
1217 CharUnits::fromQuantity(Alignment),
1218 getContext(), TBAAInfo),
1223 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
1225 Store->setAlignment(Alignment);
1227 llvm::MDNode *TBAAPath = CGM.getTBAAStructTagInfo(TBAABaseType, TBAAInfo,
1230 CGM.DecorateInstruction(Store, TBAAPath, false/*ConvertTypeToTag*/);
1234 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue,
1236 EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(),
1237 lvalue.getAlignment().getQuantity(), lvalue.getType(),
1238 lvalue.getTBAAInfo(), isInit, lvalue.getTBAABaseType(),
1239 lvalue.getTBAAOffset());
1242 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
1243 /// method emits the address of the lvalue, then loads the result as an rvalue,
1244 /// returning the rvalue.
1245 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
1246 if (LV.isObjCWeak()) {
1247 // load of a __weak object.
1248 llvm::Value *AddrWeakObj = LV.getAddress();
1249 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
1252 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1253 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress());
1254 Object = EmitObjCConsumeObject(LV.getType(), Object);
1255 return RValue::get(Object);
1258 if (LV.isSimple()) {
1259 assert(!LV.getType()->isFunctionType());
1261 // Everything needs a load.
1262 return RValue::get(EmitLoadOfScalar(LV, Loc));
1265 if (LV.isVectorElt()) {
1266 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddr(),
1267 LV.isVolatileQualified());
1268 Load->setAlignment(LV.getAlignment().getQuantity());
1269 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(),
1273 // If this is a reference to a subset of the elements of a vector, either
1274 // shuffle the input or extract/insert them as appropriate.
1275 if (LV.isExtVectorElt())
1276 return EmitLoadOfExtVectorElementLValue(LV);
1278 assert(LV.isBitField() && "Unknown LValue type!");
1279 return EmitLoadOfBitfieldLValue(LV);
1282 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV) {
1283 const CGBitFieldInfo &Info = LV.getBitFieldInfo();
1285 // Get the output type.
1286 llvm::Type *ResLTy = ConvertType(LV.getType());
1288 llvm::Value *Ptr = LV.getBitFieldAddr();
1289 llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(),
1291 cast<llvm::LoadInst>(Val)->setAlignment(Info.StorageAlignment);
1293 if (Info.IsSigned) {
1294 assert(static_cast<unsigned>(Info.Offset + Info.Size) <= Info.StorageSize);
1295 unsigned HighBits = Info.StorageSize - Info.Offset - Info.Size;
1297 Val = Builder.CreateShl(Val, HighBits, "bf.shl");
1298 if (Info.Offset + HighBits)
1299 Val = Builder.CreateAShr(Val, Info.Offset + HighBits, "bf.ashr");
1302 Val = Builder.CreateLShr(Val, Info.Offset, "bf.lshr");
1303 if (static_cast<unsigned>(Info.Offset) + Info.Size < Info.StorageSize)
1304 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(Info.StorageSize,
1308 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast");
1310 return RValue::get(Val);
1313 // If this is a reference to a subset of the elements of a vector, create an
1314 // appropriate shufflevector.
1315 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) {
1316 llvm::LoadInst *Load = Builder.CreateLoad(LV.getExtVectorAddr(),
1317 LV.isVolatileQualified());
1318 Load->setAlignment(LV.getAlignment().getQuantity());
1319 llvm::Value *Vec = Load;
1321 const llvm::Constant *Elts = LV.getExtVectorElts();
1323 // If the result of the expression is a non-vector type, we must be extracting
1324 // a single element. Just codegen as an extractelement.
1325 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1327 unsigned InIdx = getAccessedFieldNo(0, Elts);
1328 llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx);
1329 return RValue::get(Builder.CreateExtractElement(Vec, Elt));
1332 // Always use shuffle vector to try to retain the original program structure
1333 unsigned NumResultElts = ExprVT->getNumElements();
1335 SmallVector<llvm::Constant*, 4> Mask;
1336 for (unsigned i = 0; i != NumResultElts; ++i)
1337 Mask.push_back(Builder.getInt32(getAccessedFieldNo(i, Elts)));
1339 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1340 Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
1342 return RValue::get(Vec);
1347 /// EmitStoreThroughLValue - Store the specified rvalue into the specified
1348 /// lvalue, where both are guaranteed to the have the same type, and that type
1350 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
1352 if (!Dst.isSimple()) {
1353 if (Dst.isVectorElt()) {
1354 // Read/modify/write the vector, inserting the new element.
1355 llvm::LoadInst *Load = Builder.CreateLoad(Dst.getVectorAddr(),
1356 Dst.isVolatileQualified());
1357 Load->setAlignment(Dst.getAlignment().getQuantity());
1358 llvm::Value *Vec = Load;
1359 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
1360 Dst.getVectorIdx(), "vecins");
1361 llvm::StoreInst *Store = Builder.CreateStore(Vec, Dst.getVectorAddr(),
1362 Dst.isVolatileQualified());
1363 Store->setAlignment(Dst.getAlignment().getQuantity());
1367 // If this is an update of extended vector elements, insert them as
1369 if (Dst.isExtVectorElt())
1370 return EmitStoreThroughExtVectorComponentLValue(Src, Dst);
1372 assert(Dst.isBitField() && "Unknown LValue type");
1373 return EmitStoreThroughBitfieldLValue(Src, Dst);
1376 // There's special magic for assigning into an ARC-qualified l-value.
1377 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) {
1379 case Qualifiers::OCL_None:
1380 llvm_unreachable("present but none");
1382 case Qualifiers::OCL_ExplicitNone:
1386 case Qualifiers::OCL_Strong:
1387 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true);
1390 case Qualifiers::OCL_Weak:
1391 EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(), /*ignore*/ true);
1394 case Qualifiers::OCL_Autoreleasing:
1395 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(),
1396 Src.getScalarVal()));
1397 // fall into the normal path
1402 if (Dst.isObjCWeak() && !Dst.isNonGC()) {
1403 // load of a __weak object.
1404 llvm::Value *LvalueDst = Dst.getAddress();
1405 llvm::Value *src = Src.getScalarVal();
1406 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
1410 if (Dst.isObjCStrong() && !Dst.isNonGC()) {
1411 // load of a __strong object.
1412 llvm::Value *LvalueDst = Dst.getAddress();
1413 llvm::Value *src = Src.getScalarVal();
1414 if (Dst.isObjCIvar()) {
1415 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
1416 llvm::Type *ResultType = ConvertType(getContext().LongTy);
1417 llvm::Value *RHS = EmitScalarExpr(Dst.getBaseIvarExp());
1418 llvm::Value *dst = RHS;
1419 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
1421 Builder.CreatePtrToInt(LvalueDst, ResultType, "sub.ptr.lhs.cast");
1422 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
1423 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
1425 } else if (Dst.isGlobalObjCRef()) {
1426 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
1427 Dst.isThreadLocalRef());
1430 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
1434 assert(Src.isScalar() && "Can't emit an agg store with this method");
1435 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit);
1438 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
1439 llvm::Value **Result) {
1440 const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
1441 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType());
1442 llvm::Value *Ptr = Dst.getBitFieldAddr();
1444 // Get the source value, truncated to the width of the bit-field.
1445 llvm::Value *SrcVal = Src.getScalarVal();
1447 // Cast the source to the storage type and shift it into place.
1448 SrcVal = Builder.CreateIntCast(SrcVal,
1449 Ptr->getType()->getPointerElementType(),
1450 /*IsSigned=*/false);
1451 llvm::Value *MaskedVal = SrcVal;
1453 // See if there are other bits in the bitfield's storage we'll need to load
1454 // and mask together with source before storing.
1455 if (Info.StorageSize != Info.Size) {
1456 assert(Info.StorageSize > Info.Size && "Invalid bitfield size.");
1457 llvm::Value *Val = Builder.CreateLoad(Ptr, Dst.isVolatileQualified(),
1459 cast<llvm::LoadInst>(Val)->setAlignment(Info.StorageAlignment);
1461 // Mask the source value as needed.
1462 if (!hasBooleanRepresentation(Dst.getType()))
1463 SrcVal = Builder.CreateAnd(SrcVal,
1464 llvm::APInt::getLowBitsSet(Info.StorageSize,
1469 SrcVal = Builder.CreateShl(SrcVal, Info.Offset, "bf.shl");
1471 // Mask out the original value.
1472 Val = Builder.CreateAnd(Val,
1473 ~llvm::APInt::getBitsSet(Info.StorageSize,
1475 Info.Offset + Info.Size),
1478 // Or together the unchanged values and the source value.
1479 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set");
1481 assert(Info.Offset == 0);
1484 // Write the new value back out.
1485 llvm::StoreInst *Store = Builder.CreateStore(SrcVal, Ptr,
1486 Dst.isVolatileQualified());
1487 Store->setAlignment(Info.StorageAlignment);
1489 // Return the new value of the bit-field, if requested.
1491 llvm::Value *ResultVal = MaskedVal;
1493 // Sign extend the value if needed.
1494 if (Info.IsSigned) {
1495 assert(Info.Size <= Info.StorageSize);
1496 unsigned HighBits = Info.StorageSize - Info.Size;
1498 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl");
1499 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr");
1503 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned,
1505 *Result = EmitFromMemory(ResultVal, Dst.getType());
1509 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
1511 // This access turns into a read/modify/write of the vector. Load the input
1513 llvm::LoadInst *Load = Builder.CreateLoad(Dst.getExtVectorAddr(),
1514 Dst.isVolatileQualified());
1515 Load->setAlignment(Dst.getAlignment().getQuantity());
1516 llvm::Value *Vec = Load;
1517 const llvm::Constant *Elts = Dst.getExtVectorElts();
1519 llvm::Value *SrcVal = Src.getScalarVal();
1521 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) {
1522 unsigned NumSrcElts = VTy->getNumElements();
1523 unsigned NumDstElts =
1524 cast<llvm::VectorType>(Vec->getType())->getNumElements();
1525 if (NumDstElts == NumSrcElts) {
1526 // Use shuffle vector is the src and destination are the same number of
1527 // elements and restore the vector mask since it is on the side it will be
1529 SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
1530 for (unsigned i = 0; i != NumSrcElts; ++i)
1531 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i);
1533 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1534 Vec = Builder.CreateShuffleVector(SrcVal,
1535 llvm::UndefValue::get(Vec->getType()),
1537 } else if (NumDstElts > NumSrcElts) {
1538 // Extended the source vector to the same length and then shuffle it
1539 // into the destination.
1540 // FIXME: since we're shuffling with undef, can we just use the indices
1541 // into that? This could be simpler.
1542 SmallVector<llvm::Constant*, 4> ExtMask;
1543 for (unsigned i = 0; i != NumSrcElts; ++i)
1544 ExtMask.push_back(Builder.getInt32(i));
1545 ExtMask.resize(NumDstElts, llvm::UndefValue::get(Int32Ty));
1546 llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask);
1547 llvm::Value *ExtSrcVal =
1548 Builder.CreateShuffleVector(SrcVal,
1549 llvm::UndefValue::get(SrcVal->getType()),
1552 SmallVector<llvm::Constant*, 4> Mask;
1553 for (unsigned i = 0; i != NumDstElts; ++i)
1554 Mask.push_back(Builder.getInt32(i));
1556 // When the vector size is odd and .odd or .hi is used, the last element
1557 // of the Elts constant array will be one past the size of the vector.
1558 // Ignore the last element here, if it is greater than the mask size.
1559 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size())
1562 // modify when what gets shuffled in
1563 for (unsigned i = 0; i != NumSrcElts; ++i)
1564 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i+NumDstElts);
1565 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1566 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV);
1568 // We should never shorten the vector
1569 llvm_unreachable("unexpected shorten vector length");
1572 // If the Src is a scalar (not a vector) it must be updating one element.
1573 unsigned InIdx = getAccessedFieldNo(0, Elts);
1574 llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx);
1575 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt);
1578 llvm::StoreInst *Store = Builder.CreateStore(Vec, Dst.getExtVectorAddr(),
1579 Dst.isVolatileQualified());
1580 Store->setAlignment(Dst.getAlignment().getQuantity());
1583 // setObjCGCLValueClass - sets class of he lvalue for the purpose of
1584 // generating write-barries API. It is currently a global, ivar,
1586 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
1588 bool IsMemberAccess=false) {
1589 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC)
1592 if (isa<ObjCIvarRefExpr>(E)) {
1593 QualType ExpTy = E->getType();
1594 if (IsMemberAccess && ExpTy->isPointerType()) {
1595 // If ivar is a structure pointer, assigning to field of
1596 // this struct follows gcc's behavior and makes it a non-ivar
1597 // writer-barrier conservatively.
1598 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1599 if (ExpTy->isRecordType()) {
1600 LV.setObjCIvar(false);
1604 LV.setObjCIvar(true);
1605 ObjCIvarRefExpr *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr*>(E));
1606 LV.setBaseIvarExp(Exp->getBase());
1607 LV.setObjCArray(E->getType()->isArrayType());
1611 if (const DeclRefExpr *Exp = dyn_cast<DeclRefExpr>(E)) {
1612 if (const VarDecl *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
1613 if (VD->hasGlobalStorage()) {
1614 LV.setGlobalObjCRef(true);
1615 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None);
1618 LV.setObjCArray(E->getType()->isArrayType());
1622 if (const UnaryOperator *Exp = dyn_cast<UnaryOperator>(E)) {
1623 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1627 if (const ParenExpr *Exp = dyn_cast<ParenExpr>(E)) {
1628 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1629 if (LV.isObjCIvar()) {
1630 // If cast is to a structure pointer, follow gcc's behavior and make it
1631 // a non-ivar write-barrier.
1632 QualType ExpTy = E->getType();
1633 if (ExpTy->isPointerType())
1634 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1635 if (ExpTy->isRecordType())
1636 LV.setObjCIvar(false);
1641 if (const GenericSelectionExpr *Exp = dyn_cast<GenericSelectionExpr>(E)) {
1642 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV);
1646 if (const ImplicitCastExpr *Exp = dyn_cast<ImplicitCastExpr>(E)) {
1647 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1651 if (const CStyleCastExpr *Exp = dyn_cast<CStyleCastExpr>(E)) {
1652 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1656 if (const ObjCBridgedCastExpr *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) {
1657 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1661 if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
1662 setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1663 if (LV.isObjCIvar() && !LV.isObjCArray())
1664 // Using array syntax to assigning to what an ivar points to is not
1665 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
1666 LV.setObjCIvar(false);
1667 else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
1668 // Using array syntax to assigning to what global points to is not
1669 // same as assigning to the global itself. {id *G;} G[i] = 0;
1670 LV.setGlobalObjCRef(false);
1674 if (const MemberExpr *Exp = dyn_cast<MemberExpr>(E)) {
1675 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true);
1676 // We don't know if member is an 'ivar', but this flag is looked at
1677 // only in the context of LV.isObjCIvar().
1678 LV.setObjCArray(E->getType()->isArrayType());
1683 static llvm::Value *
1684 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF,
1685 llvm::Value *V, llvm::Type *IRType,
1686 StringRef Name = StringRef()) {
1687 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace();
1688 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name);
1691 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
1692 const Expr *E, const VarDecl *VD) {
1693 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
1694 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType());
1695 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy);
1696 CharUnits Alignment = CGF.getContext().getDeclAlign(VD);
1697 QualType T = E->getType();
1699 if (VD->getType()->isReferenceType()) {
1700 llvm::LoadInst *LI = CGF.Builder.CreateLoad(V);
1701 LI->setAlignment(Alignment.getQuantity());
1703 LV = CGF.MakeNaturalAlignAddrLValue(V, T);
1705 LV = CGF.MakeAddrLValue(V, E->getType(), Alignment);
1707 setObjCGCLValueClass(CGF.getContext(), E, LV);
1711 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
1712 const Expr *E, const FunctionDecl *FD) {
1713 llvm::Value *V = CGF.CGM.GetAddrOfFunction(FD);
1714 if (!FD->hasPrototype()) {
1715 if (const FunctionProtoType *Proto =
1716 FD->getType()->getAs<FunctionProtoType>()) {
1717 // Ugly case: for a K&R-style definition, the type of the definition
1718 // isn't the same as the type of a use. Correct for this with a
1720 QualType NoProtoType =
1721 CGF.getContext().getFunctionNoProtoType(Proto->getResultType());
1722 NoProtoType = CGF.getContext().getPointerType(NoProtoType);
1723 V = CGF.Builder.CreateBitCast(V, CGF.ConvertType(NoProtoType));
1726 CharUnits Alignment = CGF.getContext().getDeclAlign(FD);
1727 return CGF.MakeAddrLValue(V, E->getType(), Alignment);
1730 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD,
1731 llvm::Value *ThisValue) {
1732 QualType TagType = CGF.getContext().getTagDeclType(FD->getParent());
1733 LValue LV = CGF.MakeNaturalAlignAddrLValue(ThisValue, TagType);
1734 return CGF.EmitLValueForField(LV, FD);
1737 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
1738 const NamedDecl *ND = E->getDecl();
1739 CharUnits Alignment = getContext().getDeclAlign(ND);
1740 QualType T = E->getType();
1742 // A DeclRefExpr for a reference initialized by a constant expression can
1743 // appear without being odr-used. Directly emit the constant initializer.
1744 if (const VarDecl *VD = dyn_cast<VarDecl>(ND)) {
1745 const Expr *Init = VD->getAnyInitializer(VD);
1746 if (Init && !isa<ParmVarDecl>(VD) && VD->getType()->isReferenceType() &&
1747 VD->isUsableInConstantExpressions(getContext()) &&
1748 VD->checkInitIsICE()) {
1749 llvm::Constant *Val =
1750 CGM.EmitConstantValue(*VD->evaluateValue(), VD->getType(), this);
1751 assert(Val && "failed to emit reference constant expression");
1752 // FIXME: Eventually we will want to emit vector element references.
1753 return MakeAddrLValue(Val, T, Alignment);
1757 // FIXME: We should be able to assert this for FunctionDecls as well!
1758 // FIXME: We should be able to assert this for all DeclRefExprs, not just
1759 // those with a valid source location.
1760 assert((ND->isUsed(false) || !isa<VarDecl>(ND) ||
1761 !E->getLocation().isValid()) &&
1762 "Should not use decl without marking it used!");
1764 if (ND->hasAttr<WeakRefAttr>()) {
1765 const ValueDecl *VD = cast<ValueDecl>(ND);
1766 llvm::Constant *Aliasee = CGM.GetWeakRefReference(VD);
1767 return MakeAddrLValue(Aliasee, T, Alignment);
1770 if (const VarDecl *VD = dyn_cast<VarDecl>(ND)) {
1771 // Check if this is a global variable.
1772 if (VD->hasLinkage() || VD->isStaticDataMember()) {
1773 // If it's thread_local, emit a call to its wrapper function instead.
1774 if (VD->getTLSKind() == VarDecl::TLS_Dynamic)
1775 return CGM.getCXXABI().EmitThreadLocalDeclRefExpr(*this, E);
1776 return EmitGlobalVarDeclLValue(*this, E, VD);
1779 bool isBlockVariable = VD->hasAttr<BlocksAttr>();
1781 llvm::Value *V = LocalDeclMap.lookup(VD);
1782 if (!V && VD->isStaticLocal())
1783 V = CGM.getStaticLocalDeclAddress(VD);
1785 // Use special handling for lambdas.
1787 if (FieldDecl *FD = LambdaCaptureFields.lookup(VD)) {
1788 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
1789 } else if (CapturedStmtInfo) {
1790 if (const FieldDecl *FD = CapturedStmtInfo->lookup(VD))
1791 return EmitCapturedFieldLValue(*this, FD,
1792 CapturedStmtInfo->getContextValue());
1795 assert(isa<BlockDecl>(CurCodeDecl) && E->refersToEnclosingLocal());
1796 return MakeAddrLValue(GetAddrOfBlockDecl(VD, isBlockVariable),
1800 assert(V && "DeclRefExpr not entered in LocalDeclMap?");
1802 if (isBlockVariable)
1803 V = BuildBlockByrefAddress(V, VD);
1806 if (VD->getType()->isReferenceType()) {
1807 llvm::LoadInst *LI = Builder.CreateLoad(V);
1808 LI->setAlignment(Alignment.getQuantity());
1810 LV = MakeNaturalAlignAddrLValue(V, T);
1812 LV = MakeAddrLValue(V, T, Alignment);
1815 bool isLocalStorage = VD->hasLocalStorage();
1817 bool NonGCable = isLocalStorage &&
1818 !VD->getType()->isReferenceType() &&
1821 LV.getQuals().removeObjCGCAttr();
1825 bool isImpreciseLifetime =
1826 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>());
1827 if (isImpreciseLifetime)
1828 LV.setARCPreciseLifetime(ARCImpreciseLifetime);
1829 setObjCGCLValueClass(getContext(), E, LV);
1833 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
1834 return EmitFunctionDeclLValue(*this, E, FD);
1836 llvm_unreachable("Unhandled DeclRefExpr");
1839 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
1840 // __extension__ doesn't affect lvalue-ness.
1841 if (E->getOpcode() == UO_Extension)
1842 return EmitLValue(E->getSubExpr());
1844 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
1845 switch (E->getOpcode()) {
1846 default: llvm_unreachable("Unknown unary operator lvalue!");
1848 QualType T = E->getSubExpr()->getType()->getPointeeType();
1849 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
1851 LValue LV = MakeNaturalAlignAddrLValue(EmitScalarExpr(E->getSubExpr()), T);
1852 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
1854 // We should not generate __weak write barrier on indirect reference
1855 // of a pointer to object; as in void foo (__weak id *param); *param = 0;
1856 // But, we continue to generate __strong write barrier on indirect write
1857 // into a pointer to object.
1858 if (getLangOpts().ObjC1 &&
1859 getLangOpts().getGC() != LangOptions::NonGC &&
1861 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
1866 LValue LV = EmitLValue(E->getSubExpr());
1867 assert(LV.isSimple() && "real/imag on non-ordinary l-value");
1868 llvm::Value *Addr = LV.getAddress();
1870 // __real is valid on scalars. This is a faster way of testing that.
1871 // __imag can only produce an rvalue on scalars.
1872 if (E->getOpcode() == UO_Real &&
1873 !cast<llvm::PointerType>(Addr->getType())
1874 ->getElementType()->isStructTy()) {
1875 assert(E->getSubExpr()->getType()->isArithmeticType());
1879 assert(E->getSubExpr()->getType()->isAnyComplexType());
1881 unsigned Idx = E->getOpcode() == UO_Imag;
1882 return MakeAddrLValue(Builder.CreateStructGEP(LV.getAddress(),
1888 LValue LV = EmitLValue(E->getSubExpr());
1889 bool isInc = E->getOpcode() == UO_PreInc;
1891 if (E->getType()->isAnyComplexType())
1892 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
1894 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
1900 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
1901 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
1905 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
1906 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
1910 static llvm::Constant*
1911 GetAddrOfConstantWideString(StringRef Str,
1912 const char *GlobalName,
1913 ASTContext &Context,
1914 QualType Ty, SourceLocation Loc,
1915 CodeGenModule &CGM) {
1917 StringLiteral *SL = StringLiteral::Create(Context,
1919 StringLiteral::Wide,
1922 llvm::Constant *C = CGM.GetConstantArrayFromStringLiteral(SL);
1923 llvm::GlobalVariable *GV =
1924 new llvm::GlobalVariable(CGM.getModule(), C->getType(),
1925 !CGM.getLangOpts().WritableStrings,
1926 llvm::GlobalValue::PrivateLinkage,
1928 const unsigned WideAlignment =
1929 Context.getTypeAlignInChars(Ty).getQuantity();
1930 GV->setAlignment(WideAlignment);
1934 static void ConvertUTF8ToWideString(unsigned CharByteWidth, StringRef Source,
1935 SmallString<32>& Target) {
1936 Target.resize(CharByteWidth * (Source.size() + 1));
1937 char *ResultPtr = &Target[0];
1938 const UTF8 *ErrorPtr;
1939 bool success = ConvertUTF8toWide(CharByteWidth, Source, ResultPtr, ErrorPtr);
1942 Target.resize(ResultPtr - &Target[0]);
1945 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
1946 switch (E->getIdentType()) {
1948 return EmitUnsupportedLValue(E, "predefined expression");
1950 case PredefinedExpr::Func:
1951 case PredefinedExpr::Function:
1952 case PredefinedExpr::LFunction:
1953 case PredefinedExpr::FuncDName:
1954 case PredefinedExpr::PrettyFunction: {
1955 PredefinedExpr::IdentType IdentType = E->getIdentType();
1956 std::string GlobalVarName;
1958 switch (IdentType) {
1959 default: llvm_unreachable("Invalid type");
1960 case PredefinedExpr::Func:
1961 GlobalVarName = "__func__.";
1963 case PredefinedExpr::Function:
1964 GlobalVarName = "__FUNCTION__.";
1966 case PredefinedExpr::FuncDName:
1967 GlobalVarName = "__FUNCDNAME__.";
1969 case PredefinedExpr::LFunction:
1970 GlobalVarName = "L__FUNCTION__.";
1972 case PredefinedExpr::PrettyFunction:
1973 GlobalVarName = "__PRETTY_FUNCTION__.";
1977 StringRef FnName = CurFn->getName();
1978 if (FnName.startswith("\01"))
1979 FnName = FnName.substr(1);
1980 GlobalVarName += FnName;
1982 // If this is outside of a function use the top level decl.
1983 const Decl *CurDecl = CurCodeDecl;
1984 if (CurDecl == 0 || isa<VarDecl>(CurDecl))
1985 CurDecl = getContext().getTranslationUnitDecl();
1987 const Type *ElemType = E->getType()->getArrayElementTypeNoTypeQual();
1988 std::string FunctionName;
1989 if (isa<BlockDecl>(CurDecl)) {
1990 // Blocks use the mangled function name.
1991 // FIXME: ComputeName should handle blocks.
1992 FunctionName = FnName.str();
1993 } else if (isa<CapturedDecl>(CurDecl)) {
1994 // For a captured statement, the function name is its enclosing
1995 // function name not the one compiler generated.
1996 FunctionName = PredefinedExpr::ComputeName(IdentType, CurDecl);
1998 FunctionName = PredefinedExpr::ComputeName(IdentType, CurDecl);
1999 assert(cast<ConstantArrayType>(E->getType())->getSize() - 1 ==
2000 FunctionName.size() &&
2001 "Computed __func__ length differs from type!");
2005 if (ElemType->isWideCharType()) {
2006 SmallString<32> RawChars;
2007 ConvertUTF8ToWideString(
2008 getContext().getTypeSizeInChars(ElemType).getQuantity(),
2009 FunctionName, RawChars);
2010 C = GetAddrOfConstantWideString(RawChars,
2011 GlobalVarName.c_str(),
2017 C = CGM.GetAddrOfConstantCString(FunctionName,
2018 GlobalVarName.c_str(),
2021 return MakeAddrLValue(C, E->getType());
2026 /// Emit a type description suitable for use by a runtime sanitizer library. The
2027 /// format of a type descriptor is
2030 /// { i16 TypeKind, i16 TypeInfo }
2033 /// followed by an array of i8 containing the type name. TypeKind is 0 for an
2034 /// integer, 1 for a floating point value, and -1 for anything else.
2035 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) {
2036 // Only emit each type's descriptor once.
2037 if (llvm::Constant *C = CGM.getTypeDescriptor(T))
2040 uint16_t TypeKind = -1;
2041 uint16_t TypeInfo = 0;
2043 if (T->isIntegerType()) {
2045 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) |
2046 (T->isSignedIntegerType() ? 1 : 0);
2047 } else if (T->isFloatingType()) {
2049 TypeInfo = getContext().getTypeSize(T);
2052 // Format the type name as if for a diagnostic, including quotes and
2053 // optionally an 'aka'.
2054 SmallString<32> Buffer;
2055 CGM.getDiags().ConvertArgToString(DiagnosticsEngine::ak_qualtype,
2056 (intptr_t)T.getAsOpaquePtr(),
2057 0, 0, 0, 0, 0, 0, Buffer,
2058 ArrayRef<intptr_t>());
2060 llvm::Constant *Components[] = {
2061 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo),
2062 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer)
2064 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components);
2066 llvm::GlobalVariable *GV =
2067 new llvm::GlobalVariable(CGM.getModule(), Descriptor->getType(),
2068 /*isConstant=*/true,
2069 llvm::GlobalVariable::PrivateLinkage,
2071 GV->setUnnamedAddr(true);
2073 // Remember the descriptor for this type.
2074 CGM.setTypeDescriptor(T, GV);
2079 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) {
2080 llvm::Type *TargetTy = IntPtrTy;
2082 // Floating-point types which fit into intptr_t are bitcast to integers
2083 // and then passed directly (after zero-extension, if necessary).
2084 if (V->getType()->isFloatingPointTy()) {
2085 unsigned Bits = V->getType()->getPrimitiveSizeInBits();
2086 if (Bits <= TargetTy->getIntegerBitWidth())
2087 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(),
2091 // Integers which fit in intptr_t are zero-extended and passed directly.
2092 if (V->getType()->isIntegerTy() &&
2093 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth())
2094 return Builder.CreateZExt(V, TargetTy);
2096 // Pointers are passed directly, everything else is passed by address.
2097 if (!V->getType()->isPointerTy()) {
2098 llvm::Value *Ptr = CreateTempAlloca(V->getType());
2099 Builder.CreateStore(V, Ptr);
2102 return Builder.CreatePtrToInt(V, TargetTy);
2105 /// \brief Emit a representation of a SourceLocation for passing to a handler
2106 /// in a sanitizer runtime library. The format for this data is:
2108 /// struct SourceLocation {
2109 /// const char *Filename;
2110 /// int32_t Line, Column;
2113 /// For an invalid SourceLocation, the Filename pointer is null.
2114 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
2115 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
2117 llvm::Constant *Data[] = {
2118 PLoc.isValid() ? CGM.GetAddrOfConstantCString(PLoc.getFilename(), ".src")
2119 : llvm::Constant::getNullValue(Int8PtrTy),
2120 Builder.getInt32(PLoc.isValid() ? PLoc.getLine() : 0),
2121 Builder.getInt32(PLoc.isValid() ? PLoc.getColumn() : 0)
2124 return llvm::ConstantStruct::getAnon(Data);
2127 void CodeGenFunction::EmitCheck(llvm::Value *Checked, StringRef CheckName,
2128 ArrayRef<llvm::Constant *> StaticArgs,
2129 ArrayRef<llvm::Value *> DynamicArgs,
2130 CheckRecoverableKind RecoverKind) {
2131 assert(SanOpts != &SanitizerOptions::Disabled);
2133 if (CGM.getCodeGenOpts().SanitizeUndefinedTrapOnError) {
2134 assert (RecoverKind != CRK_AlwaysRecoverable &&
2135 "Runtime call required for AlwaysRecoverable kind!");
2136 return EmitTrapCheck(Checked);
2139 llvm::BasicBlock *Cont = createBasicBlock("cont");
2141 llvm::BasicBlock *Handler = createBasicBlock("handler." + CheckName);
2143 llvm::Instruction *Branch = Builder.CreateCondBr(Checked, Cont, Handler);
2145 // Give hint that we very much don't expect to execute the handler
2146 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
2147 llvm::MDBuilder MDHelper(getLLVMContext());
2148 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
2149 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node);
2153 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
2154 llvm::GlobalValue *InfoPtr =
2155 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
2156 llvm::GlobalVariable::PrivateLinkage, Info);
2157 InfoPtr->setUnnamedAddr(true);
2159 SmallVector<llvm::Value *, 4> Args;
2160 SmallVector<llvm::Type *, 4> ArgTypes;
2161 Args.reserve(DynamicArgs.size() + 1);
2162 ArgTypes.reserve(DynamicArgs.size() + 1);
2164 // Handler functions take an i8* pointing to the (handler-specific) static
2165 // information block, followed by a sequence of intptr_t arguments
2166 // representing operand values.
2167 Args.push_back(Builder.CreateBitCast(InfoPtr, Int8PtrTy));
2168 ArgTypes.push_back(Int8PtrTy);
2169 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) {
2170 Args.push_back(EmitCheckValue(DynamicArgs[i]));
2171 ArgTypes.push_back(IntPtrTy);
2174 bool Recover = (RecoverKind == CRK_AlwaysRecoverable) ||
2175 ((RecoverKind == CRK_Recoverable) &&
2176 CGM.getCodeGenOpts().SanitizeRecover);
2178 llvm::FunctionType *FnType =
2179 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false);
2180 llvm::AttrBuilder B;
2182 B.addAttribute(llvm::Attribute::NoReturn)
2183 .addAttribute(llvm::Attribute::NoUnwind);
2185 B.addAttribute(llvm::Attribute::UWTable);
2187 // Checks that have two variants use a suffix to differentiate them
2188 bool NeedsAbortSuffix = (RecoverKind != CRK_Unrecoverable) &&
2189 !CGM.getCodeGenOpts().SanitizeRecover;
2190 std::string FunctionName = ("__ubsan_handle_" + CheckName +
2191 (NeedsAbortSuffix? "_abort" : "")).str();
2193 CGM.CreateRuntimeFunction(FnType, FunctionName,
2194 llvm::AttributeSet::get(getLLVMContext(),
2195 llvm::AttributeSet::FunctionIndex,
2197 llvm::CallInst *HandlerCall = EmitNounwindRuntimeCall(Fn, Args);
2199 Builder.CreateBr(Cont);
2201 HandlerCall->setDoesNotReturn();
2202 Builder.CreateUnreachable();
2208 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked) {
2209 llvm::BasicBlock *Cont = createBasicBlock("cont");
2211 // If we're optimizing, collapse all calls to trap down to just one per
2212 // function to save on code size.
2213 if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
2214 TrapBB = createBasicBlock("trap");
2215 Builder.CreateCondBr(Checked, Cont, TrapBB);
2217 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::trap);
2218 llvm::CallInst *TrapCall = Builder.CreateCall(F);
2219 TrapCall->setDoesNotReturn();
2220 TrapCall->setDoesNotThrow();
2221 Builder.CreateUnreachable();
2223 Builder.CreateCondBr(Checked, Cont, TrapBB);
2229 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
2230 /// array to pointer, return the array subexpression.
2231 static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
2232 // If this isn't just an array->pointer decay, bail out.
2233 const CastExpr *CE = dyn_cast<CastExpr>(E);
2234 if (CE == 0 || CE->getCastKind() != CK_ArrayToPointerDecay)
2237 // If this is a decay from variable width array, bail out.
2238 const Expr *SubExpr = CE->getSubExpr();
2239 if (SubExpr->getType()->isVariableArrayType())
2245 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
2247 // The index must always be an integer, which is not an aggregate. Emit it.
2248 llvm::Value *Idx = EmitScalarExpr(E->getIdx());
2249 QualType IdxTy = E->getIdx()->getType();
2250 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType();
2252 if (SanOpts->ArrayBounds)
2253 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed);
2255 // If the base is a vector type, then we are forming a vector element lvalue
2256 // with this subscript.
2257 if (E->getBase()->getType()->isVectorType()) {
2258 // Emit the vector as an lvalue to get its address.
2259 LValue LHS = EmitLValue(E->getBase());
2260 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
2261 Idx = Builder.CreateIntCast(Idx, Int32Ty, IdxSigned, "vidx");
2262 return LValue::MakeVectorElt(LHS.getAddress(), Idx,
2263 E->getBase()->getType(), LHS.getAlignment());
2266 // Extend or truncate the index type to 32 or 64-bits.
2267 if (Idx->getType() != IntPtrTy)
2268 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
2270 // We know that the pointer points to a type of the correct size, unless the
2271 // size is a VLA or Objective-C interface.
2272 llvm::Value *Address = 0;
2273 CharUnits ArrayAlignment;
2274 if (const VariableArrayType *vla =
2275 getContext().getAsVariableArrayType(E->getType())) {
2276 // The base must be a pointer, which is not an aggregate. Emit
2277 // it. It needs to be emitted first in case it's what captures
2279 Address = EmitScalarExpr(E->getBase());
2281 // The element count here is the total number of non-VLA elements.
2282 llvm::Value *numElements = getVLASize(vla).first;
2284 // Effectively, the multiply by the VLA size is part of the GEP.
2285 // GEP indexes are signed, and scaling an index isn't permitted to
2286 // signed-overflow, so we use the same semantics for our explicit
2287 // multiply. We suppress this if overflow is not undefined behavior.
2288 if (getLangOpts().isSignedOverflowDefined()) {
2289 Idx = Builder.CreateMul(Idx, numElements);
2290 Address = Builder.CreateGEP(Address, Idx, "arrayidx");
2292 Idx = Builder.CreateNSWMul(Idx, numElements);
2293 Address = Builder.CreateInBoundsGEP(Address, Idx, "arrayidx");
2295 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
2296 // Indexing over an interface, as in "NSString *P; P[4];"
2297 llvm::Value *InterfaceSize =
2298 llvm::ConstantInt::get(Idx->getType(),
2299 getContext().getTypeSizeInChars(OIT).getQuantity());
2301 Idx = Builder.CreateMul(Idx, InterfaceSize);
2303 // The base must be a pointer, which is not an aggregate. Emit it.
2304 llvm::Value *Base = EmitScalarExpr(E->getBase());
2305 Address = EmitCastToVoidPtr(Base);
2306 Address = Builder.CreateGEP(Address, Idx, "arrayidx");
2307 Address = Builder.CreateBitCast(Address, Base->getType());
2308 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
2309 // If this is A[i] where A is an array, the frontend will have decayed the
2310 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
2311 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
2312 // "gep x, i" here. Emit one "gep A, 0, i".
2313 assert(Array->getType()->isArrayType() &&
2314 "Array to pointer decay must have array source type!");
2316 // For simple multidimensional array indexing, set the 'accessed' flag for
2317 // better bounds-checking of the base expression.
2318 if (const ArraySubscriptExpr *ASE = dyn_cast<ArraySubscriptExpr>(Array))
2319 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
2321 ArrayLV = EmitLValue(Array);
2322 llvm::Value *ArrayPtr = ArrayLV.getAddress();
2323 llvm::Value *Zero = llvm::ConstantInt::get(Int32Ty, 0);
2324 llvm::Value *Args[] = { Zero, Idx };
2326 // Propagate the alignment from the array itself to the result.
2327 ArrayAlignment = ArrayLV.getAlignment();
2329 if (getLangOpts().isSignedOverflowDefined())
2330 Address = Builder.CreateGEP(ArrayPtr, Args, "arrayidx");
2332 Address = Builder.CreateInBoundsGEP(ArrayPtr, Args, "arrayidx");
2334 // The base must be a pointer, which is not an aggregate. Emit it.
2335 llvm::Value *Base = EmitScalarExpr(E->getBase());
2336 if (getLangOpts().isSignedOverflowDefined())
2337 Address = Builder.CreateGEP(Base, Idx, "arrayidx");
2339 Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
2342 QualType T = E->getBase()->getType()->getPointeeType();
2343 assert(!T.isNull() &&
2344 "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type");
2347 // Limit the alignment to that of the result type.
2349 if (!ArrayAlignment.isZero()) {
2350 CharUnits Align = getContext().getTypeAlignInChars(T);
2351 ArrayAlignment = std::min(Align, ArrayAlignment);
2352 LV = MakeAddrLValue(Address, T, ArrayAlignment);
2354 LV = MakeNaturalAlignAddrLValue(Address, T);
2357 LV.getQuals().setAddressSpace(E->getBase()->getType().getAddressSpace());
2359 if (getLangOpts().ObjC1 &&
2360 getLangOpts().getGC() != LangOptions::NonGC) {
2361 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
2362 setObjCGCLValueClass(getContext(), E, LV);
2368 llvm::Constant *GenerateConstantVector(CGBuilderTy &Builder,
2369 SmallVectorImpl<unsigned> &Elts) {
2370 SmallVector<llvm::Constant*, 4> CElts;
2371 for (unsigned i = 0, e = Elts.size(); i != e; ++i)
2372 CElts.push_back(Builder.getInt32(Elts[i]));
2374 return llvm::ConstantVector::get(CElts);
2377 LValue CodeGenFunction::
2378 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
2379 // Emit the base vector as an l-value.
2382 // ExtVectorElementExpr's base can either be a vector or pointer to vector.
2384 // If it is a pointer to a vector, emit the address and form an lvalue with
2386 llvm::Value *Ptr = EmitScalarExpr(E->getBase());
2387 const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
2388 Base = MakeAddrLValue(Ptr, PT->getPointeeType());
2389 Base.getQuals().removeObjCGCAttr();
2390 } else if (E->getBase()->isGLValue()) {
2391 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
2392 // emit the base as an lvalue.
2393 assert(E->getBase()->getType()->isVectorType());
2394 Base = EmitLValue(E->getBase());
2396 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
2397 assert(E->getBase()->getType()->isVectorType() &&
2398 "Result must be a vector");
2399 llvm::Value *Vec = EmitScalarExpr(E->getBase());
2401 // Store the vector to memory (because LValue wants an address).
2402 llvm::Value *VecMem = CreateMemTemp(E->getBase()->getType());
2403 Builder.CreateStore(Vec, VecMem);
2404 Base = MakeAddrLValue(VecMem, E->getBase()->getType());
2408 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers());
2410 // Encode the element access list into a vector of unsigned indices.
2411 SmallVector<unsigned, 4> Indices;
2412 E->getEncodedElementAccess(Indices);
2414 if (Base.isSimple()) {
2415 llvm::Constant *CV = GenerateConstantVector(Builder, Indices);
2416 return LValue::MakeExtVectorElt(Base.getAddress(), CV, type,
2417 Base.getAlignment());
2419 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
2421 llvm::Constant *BaseElts = Base.getExtVectorElts();
2422 SmallVector<llvm::Constant *, 4> CElts;
2424 for (unsigned i = 0, e = Indices.size(); i != e; ++i)
2425 CElts.push_back(BaseElts->getAggregateElement(Indices[i]));
2426 llvm::Constant *CV = llvm::ConstantVector::get(CElts);
2427 return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV, type,
2428 Base.getAlignment());
2431 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
2432 Expr *BaseExpr = E->getBase();
2434 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
2437 llvm::Value *Ptr = EmitScalarExpr(BaseExpr);
2438 QualType PtrTy = BaseExpr->getType()->getPointeeType();
2439 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Ptr, PtrTy);
2440 BaseLV = MakeNaturalAlignAddrLValue(Ptr, PtrTy);
2442 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess);
2444 NamedDecl *ND = E->getMemberDecl();
2445 if (FieldDecl *Field = dyn_cast<FieldDecl>(ND)) {
2446 LValue LV = EmitLValueForField(BaseLV, Field);
2447 setObjCGCLValueClass(getContext(), E, LV);
2451 if (VarDecl *VD = dyn_cast<VarDecl>(ND))
2452 return EmitGlobalVarDeclLValue(*this, E, VD);
2454 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
2455 return EmitFunctionDeclLValue(*this, E, FD);
2457 llvm_unreachable("Unhandled member declaration!");
2460 /// Given that we are currently emitting a lambda, emit an l-value for
2461 /// one of its members.
2462 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) {
2463 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent()->isLambda());
2464 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent() == Field->getParent());
2465 QualType LambdaTagType =
2466 getContext().getTagDeclType(Field->getParent());
2467 LValue LambdaLV = MakeNaturalAlignAddrLValue(CXXABIThisValue, LambdaTagType);
2468 return EmitLValueForField(LambdaLV, Field);
2471 LValue CodeGenFunction::EmitLValueForField(LValue base,
2472 const FieldDecl *field) {
2473 if (field->isBitField()) {
2474 const CGRecordLayout &RL =
2475 CGM.getTypes().getCGRecordLayout(field->getParent());
2476 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field);
2477 llvm::Value *Addr = base.getAddress();
2478 unsigned Idx = RL.getLLVMFieldNo(field);
2480 // For structs, we GEP to the field that the record layout suggests.
2481 Addr = Builder.CreateStructGEP(Addr, Idx, field->getName());
2482 // Get the access type.
2483 llvm::Type *PtrTy = llvm::Type::getIntNPtrTy(
2484 getLLVMContext(), Info.StorageSize,
2485 CGM.getContext().getTargetAddressSpace(base.getType()));
2486 if (Addr->getType() != PtrTy)
2487 Addr = Builder.CreateBitCast(Addr, PtrTy);
2489 QualType fieldType =
2490 field->getType().withCVRQualifiers(base.getVRQualifiers());
2491 return LValue::MakeBitfield(Addr, Info, fieldType, base.getAlignment());
2494 const RecordDecl *rec = field->getParent();
2495 QualType type = field->getType();
2496 CharUnits alignment = getContext().getDeclAlign(field);
2498 // FIXME: It should be impossible to have an LValue without alignment for a
2500 if (!base.getAlignment().isZero())
2501 alignment = std::min(alignment, base.getAlignment());
2503 bool mayAlias = rec->hasAttr<MayAliasAttr>();
2505 llvm::Value *addr = base.getAddress();
2506 unsigned cvr = base.getVRQualifiers();
2507 bool TBAAPath = CGM.getCodeGenOpts().StructPathTBAA;
2508 if (rec->isUnion()) {
2509 // For unions, there is no pointer adjustment.
2510 assert(!type->isReferenceType() && "union has reference member");
2511 // TODO: handle path-aware TBAA for union.
2514 // For structs, we GEP to the field that the record layout suggests.
2515 unsigned idx = CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
2516 addr = Builder.CreateStructGEP(addr, idx, field->getName());
2518 // If this is a reference field, load the reference right now.
2519 if (const ReferenceType *refType = type->getAs<ReferenceType>()) {
2520 llvm::LoadInst *load = Builder.CreateLoad(addr, "ref");
2521 if (cvr & Qualifiers::Volatile) load->setVolatile(true);
2522 load->setAlignment(alignment.getQuantity());
2524 // Loading the reference will disable path-aware TBAA.
2526 if (CGM.shouldUseTBAA()) {
2529 tbaa = CGM.getTBAAInfo(getContext().CharTy);
2531 tbaa = CGM.getTBAAInfo(type);
2533 CGM.DecorateInstruction(load, tbaa);
2538 type = refType->getPointeeType();
2539 if (type->isIncompleteType())
2540 alignment = CharUnits();
2542 alignment = getContext().getTypeAlignInChars(type);
2543 cvr = 0; // qualifiers don't recursively apply to referencee
2547 // Make sure that the address is pointing to the right type. This is critical
2548 // for both unions and structs. A union needs a bitcast, a struct element
2549 // will need a bitcast if the LLVM type laid out doesn't match the desired
2551 addr = EmitBitCastOfLValueToProperType(*this, addr,
2552 CGM.getTypes().ConvertTypeForMem(type),
2555 if (field->hasAttr<AnnotateAttr>())
2556 addr = EmitFieldAnnotations(field, addr);
2558 LValue LV = MakeAddrLValue(addr, type, alignment);
2559 LV.getQuals().addCVRQualifiers(cvr);
2561 const ASTRecordLayout &Layout =
2562 getContext().getASTRecordLayout(field->getParent());
2563 // Set the base type to be the base type of the base LValue and
2564 // update offset to be relative to the base type.
2565 LV.setTBAABaseType(mayAlias ? getContext().CharTy : base.getTBAABaseType());
2566 LV.setTBAAOffset(mayAlias ? 0 : base.getTBAAOffset() +
2567 Layout.getFieldOffset(field->getFieldIndex()) /
2568 getContext().getCharWidth());
2571 // __weak attribute on a field is ignored.
2572 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
2573 LV.getQuals().removeObjCGCAttr();
2575 // Fields of may_alias structs act like 'char' for TBAA purposes.
2576 // FIXME: this should get propagated down through anonymous structs
2578 if (mayAlias && LV.getTBAAInfo())
2579 LV.setTBAAInfo(CGM.getTBAAInfo(getContext().CharTy));
2585 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base,
2586 const FieldDecl *Field) {
2587 QualType FieldType = Field->getType();
2589 if (!FieldType->isReferenceType())
2590 return EmitLValueForField(Base, Field);
2592 const CGRecordLayout &RL =
2593 CGM.getTypes().getCGRecordLayout(Field->getParent());
2594 unsigned idx = RL.getLLVMFieldNo(Field);
2595 llvm::Value *V = Builder.CreateStructGEP(Base.getAddress(), idx);
2596 assert(!FieldType.getObjCGCAttr() && "fields cannot have GC attrs");
2598 // Make sure that the address is pointing to the right type. This is critical
2599 // for both unions and structs. A union needs a bitcast, a struct element
2600 // will need a bitcast if the LLVM type laid out doesn't match the desired
2602 llvm::Type *llvmType = ConvertTypeForMem(FieldType);
2603 V = EmitBitCastOfLValueToProperType(*this, V, llvmType, Field->getName());
2605 CharUnits Alignment = getContext().getDeclAlign(Field);
2607 // FIXME: It should be impossible to have an LValue without alignment for a
2609 if (!Base.getAlignment().isZero())
2610 Alignment = std::min(Alignment, Base.getAlignment());
2612 return MakeAddrLValue(V, FieldType, Alignment);
2615 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
2616 if (E->isFileScope()) {
2617 llvm::Value *GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E);
2618 return MakeAddrLValue(GlobalPtr, E->getType());
2620 if (E->getType()->isVariablyModifiedType())
2621 // make sure to emit the VLA size.
2622 EmitVariablyModifiedType(E->getType());
2624 llvm::Value *DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
2625 const Expr *InitExpr = E->getInitializer();
2626 LValue Result = MakeAddrLValue(DeclPtr, E->getType());
2628 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(),
2634 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) {
2635 if (!E->isGLValue())
2636 // Initializing an aggregate temporary in C++11: T{...}.
2637 return EmitAggExprToLValue(E);
2639 // An lvalue initializer list must be initializing a reference.
2640 assert(E->getNumInits() == 1 && "reference init with multiple values");
2641 return EmitLValue(E->getInit(0));
2644 LValue CodeGenFunction::
2645 EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
2646 if (!expr->isGLValue()) {
2647 // ?: here should be an aggregate.
2648 assert(hasAggregateEvaluationKind(expr->getType()) &&
2649 "Unexpected conditional operator!");
2650 return EmitAggExprToLValue(expr);
2653 OpaqueValueMapping binding(*this, expr);
2655 const Expr *condExpr = expr->getCond();
2657 if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
2658 const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
2659 if (!CondExprBool) std::swap(live, dead);
2661 if (!ContainsLabel(dead))
2662 return EmitLValue(live);
2665 llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
2666 llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
2667 llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
2669 ConditionalEvaluation eval(*this);
2670 EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock);
2672 // Any temporaries created here are conditional.
2673 EmitBlock(lhsBlock);
2675 LValue lhs = EmitLValue(expr->getTrueExpr());
2678 if (!lhs.isSimple())
2679 return EmitUnsupportedLValue(expr, "conditional operator");
2681 lhsBlock = Builder.GetInsertBlock();
2682 Builder.CreateBr(contBlock);
2684 // Any temporaries created here are conditional.
2685 EmitBlock(rhsBlock);
2687 LValue rhs = EmitLValue(expr->getFalseExpr());
2689 if (!rhs.isSimple())
2690 return EmitUnsupportedLValue(expr, "conditional operator");
2691 rhsBlock = Builder.GetInsertBlock();
2693 EmitBlock(contBlock);
2695 llvm::PHINode *phi = Builder.CreatePHI(lhs.getAddress()->getType(), 2,
2697 phi->addIncoming(lhs.getAddress(), lhsBlock);
2698 phi->addIncoming(rhs.getAddress(), rhsBlock);
2699 return MakeAddrLValue(phi, expr->getType());
2702 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference
2703 /// type. If the cast is to a reference, we can have the usual lvalue result,
2704 /// otherwise if a cast is needed by the code generator in an lvalue context,
2705 /// then it must mean that we need the address of an aggregate in order to
2706 /// access one of its members. This can happen for all the reasons that casts
2707 /// are permitted with aggregate result, including noop aggregate casts, and
2708 /// cast from scalar to union.
2709 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
2710 switch (E->getCastKind()) {
2713 case CK_ArrayToPointerDecay:
2714 case CK_FunctionToPointerDecay:
2715 case CK_NullToMemberPointer:
2716 case CK_NullToPointer:
2717 case CK_IntegralToPointer:
2718 case CK_PointerToIntegral:
2719 case CK_PointerToBoolean:
2720 case CK_VectorSplat:
2721 case CK_IntegralCast:
2722 case CK_IntegralToBoolean:
2723 case CK_IntegralToFloating:
2724 case CK_FloatingToIntegral:
2725 case CK_FloatingToBoolean:
2726 case CK_FloatingCast:
2727 case CK_FloatingRealToComplex:
2728 case CK_FloatingComplexToReal:
2729 case CK_FloatingComplexToBoolean:
2730 case CK_FloatingComplexCast:
2731 case CK_FloatingComplexToIntegralComplex:
2732 case CK_IntegralRealToComplex:
2733 case CK_IntegralComplexToReal:
2734 case CK_IntegralComplexToBoolean:
2735 case CK_IntegralComplexCast:
2736 case CK_IntegralComplexToFloatingComplex:
2737 case CK_DerivedToBaseMemberPointer:
2738 case CK_BaseToDerivedMemberPointer:
2739 case CK_MemberPointerToBoolean:
2740 case CK_ReinterpretMemberPointer:
2741 case CK_AnyPointerToBlockPointerCast:
2742 case CK_ARCProduceObject:
2743 case CK_ARCConsumeObject:
2744 case CK_ARCReclaimReturnedObject:
2745 case CK_ARCExtendBlockObject:
2746 case CK_CopyAndAutoreleaseBlockObject:
2747 return EmitUnsupportedLValue(E, "unexpected cast lvalue");
2750 llvm_unreachable("dependent cast kind in IR gen!");
2752 case CK_BuiltinFnToFnPtr:
2753 llvm_unreachable("builtin functions are handled elsewhere");
2755 // These are never l-values; just use the aggregate emission code.
2756 case CK_NonAtomicToAtomic:
2757 case CK_AtomicToNonAtomic:
2758 return EmitAggExprToLValue(E);
2761 LValue LV = EmitLValue(E->getSubExpr());
2762 llvm::Value *V = LV.getAddress();
2763 const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(E);
2764 return MakeAddrLValue(EmitDynamicCast(V, DCE), E->getType());
2767 case CK_ConstructorConversion:
2768 case CK_UserDefinedConversion:
2769 case CK_CPointerToObjCPointerCast:
2770 case CK_BlockPointerToObjCPointerCast:
2772 case CK_LValueToRValue:
2773 return EmitLValue(E->getSubExpr());
2775 case CK_UncheckedDerivedToBase:
2776 case CK_DerivedToBase: {
2777 const RecordType *DerivedClassTy =
2778 E->getSubExpr()->getType()->getAs<RecordType>();
2779 CXXRecordDecl *DerivedClassDecl =
2780 cast<CXXRecordDecl>(DerivedClassTy->getDecl());
2782 LValue LV = EmitLValue(E->getSubExpr());
2783 llvm::Value *This = LV.getAddress();
2785 // Perform the derived-to-base conversion
2787 GetAddressOfBaseClass(This, DerivedClassDecl,
2788 E->path_begin(), E->path_end(),
2789 /*NullCheckValue=*/false);
2791 return MakeAddrLValue(Base, E->getType());
2794 return EmitAggExprToLValue(E);
2795 case CK_BaseToDerived: {
2796 const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
2797 CXXRecordDecl *DerivedClassDecl =
2798 cast<CXXRecordDecl>(DerivedClassTy->getDecl());
2800 LValue LV = EmitLValue(E->getSubExpr());
2802 // Perform the base-to-derived conversion
2803 llvm::Value *Derived =
2804 GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
2805 E->path_begin(), E->path_end(),
2806 /*NullCheckValue=*/false);
2808 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is
2809 // performed and the object is not of the derived type.
2810 if (SanitizePerformTypeCheck)
2811 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(),
2812 Derived, E->getType());
2814 return MakeAddrLValue(Derived, E->getType());
2816 case CK_LValueBitCast: {
2817 // This must be a reinterpret_cast (or c-style equivalent).
2818 const ExplicitCastExpr *CE = cast<ExplicitCastExpr>(E);
2820 LValue LV = EmitLValue(E->getSubExpr());
2821 llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
2822 ConvertType(CE->getTypeAsWritten()));
2823 return MakeAddrLValue(V, E->getType());
2825 case CK_ObjCObjectLValueCast: {
2826 LValue LV = EmitLValue(E->getSubExpr());
2827 QualType ToType = getContext().getLValueReferenceType(E->getType());
2828 llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
2829 ConvertType(ToType));
2830 return MakeAddrLValue(V, E->getType());
2832 case CK_ZeroToOCLEvent:
2833 llvm_unreachable("NULL to OpenCL event lvalue cast is not valid");
2836 llvm_unreachable("Unhandled lvalue cast kind?");
2839 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
2840 assert(OpaqueValueMappingData::shouldBindAsLValue(e));
2841 return getOpaqueLValueMapping(e);
2844 RValue CodeGenFunction::EmitRValueForField(LValue LV,
2845 const FieldDecl *FD,
2846 SourceLocation Loc) {
2847 QualType FT = FD->getType();
2848 LValue FieldLV = EmitLValueForField(LV, FD);
2849 switch (getEvaluationKind(FT)) {
2851 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc));
2853 return FieldLV.asAggregateRValue();
2855 return EmitLoadOfLValue(FieldLV, Loc);
2857 llvm_unreachable("bad evaluation kind");
2860 //===--------------------------------------------------------------------===//
2861 // Expression Emission
2862 //===--------------------------------------------------------------------===//
2864 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
2865 ReturnValueSlot ReturnValue) {
2866 if (CGDebugInfo *DI = getDebugInfo()) {
2867 SourceLocation Loc = E->getLocStart();
2868 // Force column info to be generated so we can differentiate
2869 // multiple call sites on the same line in the debug info.
2870 const FunctionDecl* Callee = E->getDirectCallee();
2871 bool ForceColumnInfo = Callee && Callee->isInlineSpecified();
2872 DI->EmitLocation(Builder, Loc, ForceColumnInfo);
2875 // Builtins never have block type.
2876 if (E->getCallee()->getType()->isBlockPointerType())
2877 return EmitBlockCallExpr(E, ReturnValue);
2879 if (const CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(E))
2880 return EmitCXXMemberCallExpr(CE, ReturnValue);
2882 if (const CUDAKernelCallExpr *CE = dyn_cast<CUDAKernelCallExpr>(E))
2883 return EmitCUDAKernelCallExpr(CE, ReturnValue);
2885 const Decl *TargetDecl = E->getCalleeDecl();
2886 if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl)) {
2887 if (unsigned builtinID = FD->getBuiltinID())
2888 return EmitBuiltinExpr(FD, builtinID, E);
2891 if (const CXXOperatorCallExpr *CE = dyn_cast<CXXOperatorCallExpr>(E))
2892 if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl))
2893 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
2895 if (const CXXPseudoDestructorExpr *PseudoDtor
2896 = dyn_cast<CXXPseudoDestructorExpr>(E->getCallee()->IgnoreParens())) {
2897 QualType DestroyedType = PseudoDtor->getDestroyedType();
2898 if (getLangOpts().ObjCAutoRefCount &&
2899 DestroyedType->isObjCLifetimeType() &&
2900 (DestroyedType.getObjCLifetime() == Qualifiers::OCL_Strong ||
2901 DestroyedType.getObjCLifetime() == Qualifiers::OCL_Weak)) {
2902 // Automatic Reference Counting:
2903 // If the pseudo-expression names a retainable object with weak or
2904 // strong lifetime, the object shall be released.
2905 Expr *BaseExpr = PseudoDtor->getBase();
2906 llvm::Value *BaseValue = NULL;
2907 Qualifiers BaseQuals;
2909 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
2910 if (PseudoDtor->isArrow()) {
2911 BaseValue = EmitScalarExpr(BaseExpr);
2912 const PointerType *PTy = BaseExpr->getType()->getAs<PointerType>();
2913 BaseQuals = PTy->getPointeeType().getQualifiers();
2915 LValue BaseLV = EmitLValue(BaseExpr);
2916 BaseValue = BaseLV.getAddress();
2917 QualType BaseTy = BaseExpr->getType();
2918 BaseQuals = BaseTy.getQualifiers();
2921 switch (PseudoDtor->getDestroyedType().getObjCLifetime()) {
2922 case Qualifiers::OCL_None:
2923 case Qualifiers::OCL_ExplicitNone:
2924 case Qualifiers::OCL_Autoreleasing:
2927 case Qualifiers::OCL_Strong:
2928 EmitARCRelease(Builder.CreateLoad(BaseValue,
2929 PseudoDtor->getDestroyedType().isVolatileQualified()),
2930 ARCPreciseLifetime);
2933 case Qualifiers::OCL_Weak:
2934 EmitARCDestroyWeak(BaseValue);
2938 // C++ [expr.pseudo]p1:
2939 // The result shall only be used as the operand for the function call
2940 // operator (), and the result of such a call has type void. The only
2941 // effect is the evaluation of the postfix-expression before the dot or
2943 EmitScalarExpr(E->getCallee());
2946 return RValue::get(0);
2949 llvm::Value *Callee = EmitScalarExpr(E->getCallee());
2950 return EmitCall(E->getCallee()->getType(), Callee, E->getLocStart(),
2951 ReturnValue, E->arg_begin(), E->arg_end(), TargetDecl);
2954 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
2955 // Comma expressions just emit their LHS then their RHS as an l-value.
2956 if (E->getOpcode() == BO_Comma) {
2957 EmitIgnoredExpr(E->getLHS());
2958 EnsureInsertPoint();
2959 return EmitLValue(E->getRHS());
2962 if (E->getOpcode() == BO_PtrMemD ||
2963 E->getOpcode() == BO_PtrMemI)
2964 return EmitPointerToDataMemberBinaryExpr(E);
2966 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
2968 // Note that in all of these cases, __block variables need the RHS
2969 // evaluated first just in case the variable gets moved by the RHS.
2971 switch (getEvaluationKind(E->getType())) {
2973 switch (E->getLHS()->getType().getObjCLifetime()) {
2974 case Qualifiers::OCL_Strong:
2975 return EmitARCStoreStrong(E, /*ignored*/ false).first;
2977 case Qualifiers::OCL_Autoreleasing:
2978 return EmitARCStoreAutoreleasing(E).first;
2980 // No reason to do any of these differently.
2981 case Qualifiers::OCL_None:
2982 case Qualifiers::OCL_ExplicitNone:
2983 case Qualifiers::OCL_Weak:
2987 RValue RV = EmitAnyExpr(E->getRHS());
2988 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
2989 EmitStoreThroughLValue(RV, LV);
2994 return EmitComplexAssignmentLValue(E);
2997 return EmitAggExprToLValue(E);
2999 llvm_unreachable("bad evaluation kind");
3002 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
3003 RValue RV = EmitCallExpr(E);
3006 return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
3008 assert(E->getCallReturnType()->isReferenceType() &&
3009 "Can't have a scalar return unless the return type is a "
3012 return MakeAddrLValue(RV.getScalarVal(), E->getType());
3015 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
3016 // FIXME: This shouldn't require another copy.
3017 return EmitAggExprToLValue(E);
3020 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
3021 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
3022 && "binding l-value to type which needs a temporary");
3023 AggValueSlot Slot = CreateAggTemp(E->getType());
3024 EmitCXXConstructExpr(E, Slot);
3025 return MakeAddrLValue(Slot.getAddr(), E->getType());
3029 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
3030 return MakeAddrLValue(EmitCXXTypeidExpr(E), E->getType());
3033 llvm::Value *CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) {
3034 return Builder.CreateBitCast(CGM.GetAddrOfUuidDescriptor(E),
3035 ConvertType(E->getType())->getPointerTo());
3038 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) {
3039 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType());
3043 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
3044 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
3045 Slot.setExternallyDestructed();
3046 EmitAggExpr(E->getSubExpr(), Slot);
3047 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddr());
3048 return MakeAddrLValue(Slot.getAddr(), E->getType());
3052 CodeGenFunction::EmitLambdaLValue(const LambdaExpr *E) {
3053 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
3054 EmitLambdaExpr(E, Slot);
3055 return MakeAddrLValue(Slot.getAddr(), E->getType());
3058 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
3059 RValue RV = EmitObjCMessageExpr(E);
3062 return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
3064 assert(E->getMethodDecl()->getResultType()->isReferenceType() &&
3065 "Can't have a scalar return unless the return type is a "
3068 return MakeAddrLValue(RV.getScalarVal(), E->getType());
3071 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
3073 CGM.getObjCRuntime().GetSelector(*this, E->getSelector(), true);
3074 return MakeAddrLValue(V, E->getType());
3077 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
3078 const ObjCIvarDecl *Ivar) {
3079 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
3082 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
3083 llvm::Value *BaseValue,
3084 const ObjCIvarDecl *Ivar,
3085 unsigned CVRQualifiers) {
3086 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
3087 Ivar, CVRQualifiers);
3090 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
3091 // FIXME: A lot of the code below could be shared with EmitMemberExpr.
3092 llvm::Value *BaseValue = 0;
3093 const Expr *BaseExpr = E->getBase();
3094 Qualifiers BaseQuals;
3097 BaseValue = EmitScalarExpr(BaseExpr);
3098 ObjectTy = BaseExpr->getType()->getPointeeType();
3099 BaseQuals = ObjectTy.getQualifiers();
3101 LValue BaseLV = EmitLValue(BaseExpr);
3102 // FIXME: this isn't right for bitfields.
3103 BaseValue = BaseLV.getAddress();
3104 ObjectTy = BaseExpr->getType();
3105 BaseQuals = ObjectTy.getQualifiers();
3109 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
3110 BaseQuals.getCVRQualifiers());
3111 setObjCGCLValueClass(getContext(), E, LV);
3115 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
3116 // Can only get l-value for message expression returning aggregate type
3117 RValue RV = EmitAnyExprToTemp(E);
3118 return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
3121 RValue CodeGenFunction::EmitCall(QualType CalleeType, llvm::Value *Callee,
3122 SourceLocation CallLoc,
3123 ReturnValueSlot ReturnValue,
3124 CallExpr::const_arg_iterator ArgBeg,
3125 CallExpr::const_arg_iterator ArgEnd,
3126 const Decl *TargetDecl) {
3127 // Get the actual function type. The callee type will always be a pointer to
3128 // function type or a block pointer type.
3129 assert(CalleeType->isFunctionPointerType() &&
3130 "Call must have function pointer type!");
3132 CalleeType = getContext().getCanonicalType(CalleeType);
3134 const FunctionType *FnType
3135 = cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType());
3137 // Force column info to differentiate multiple inlined call sites on
3138 // the same line, analoguous to EmitCallExpr.
3139 bool ForceColumnInfo = false;
3140 if (const FunctionDecl* FD = dyn_cast_or_null<const FunctionDecl>(TargetDecl))
3141 ForceColumnInfo = FD->isInlineSpecified();
3143 if (getLangOpts().CPlusPlus && SanOpts->Function &&
3144 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
3145 if (llvm::Constant *PrefixSig =
3146 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
3147 llvm::Constant *FTRTTIConst =
3148 CGM.GetAddrOfRTTIDescriptor(QualType(FnType, 0), /*ForEH=*/true);
3149 llvm::Type *PrefixStructTyElems[] = {
3150 PrefixSig->getType(),
3151 FTRTTIConst->getType()
3153 llvm::StructType *PrefixStructTy = llvm::StructType::get(
3154 CGM.getLLVMContext(), PrefixStructTyElems, /*isPacked=*/true);
3156 llvm::Value *CalleePrefixStruct = Builder.CreateBitCast(
3157 Callee, llvm::PointerType::getUnqual(PrefixStructTy));
3158 llvm::Value *CalleeSigPtr =
3159 Builder.CreateConstGEP2_32(CalleePrefixStruct, 0, 0);
3160 llvm::Value *CalleeSig = Builder.CreateLoad(CalleeSigPtr);
3161 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig);
3163 llvm::BasicBlock *Cont = createBasicBlock("cont");
3164 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck");
3165 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont);
3167 EmitBlock(TypeCheck);
3168 llvm::Value *CalleeRTTIPtr =
3169 Builder.CreateConstGEP2_32(CalleePrefixStruct, 0, 1);
3170 llvm::Value *CalleeRTTI = Builder.CreateLoad(CalleeRTTIPtr);
3171 llvm::Value *CalleeRTTIMatch =
3172 Builder.CreateICmpEQ(CalleeRTTI, FTRTTIConst);
3173 llvm::Constant *StaticData[] = {
3174 EmitCheckSourceLocation(CallLoc),
3175 EmitCheckTypeDescriptor(CalleeType)
3177 EmitCheck(CalleeRTTIMatch,
3178 "function_type_mismatch",
3183 Builder.CreateBr(Cont);
3189 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), ArgBeg, ArgEnd,
3192 const CGFunctionInfo &FnInfo =
3193 CGM.getTypes().arrangeFreeFunctionCall(Args, FnType);
3196 // If the expression that denotes the called function has a type
3197 // that does not include a prototype, [the default argument
3198 // promotions are performed]. If the number of arguments does not
3199 // equal the number of parameters, the behavior is undefined. If
3200 // the function is defined with a type that includes a prototype,
3201 // and either the prototype ends with an ellipsis (, ...) or the
3202 // types of the arguments after promotion are not compatible with
3203 // the types of the parameters, the behavior is undefined. If the
3204 // function is defined with a type that does not include a
3205 // prototype, and the types of the arguments after promotion are
3206 // not compatible with those of the parameters after promotion,
3207 // the behavior is undefined [except in some trivial cases].
3208 // That is, in the general case, we should assume that a call
3209 // through an unprototyped function type works like a *non-variadic*
3210 // call. The way we make this work is to cast to the exact type
3211 // of the promoted arguments.
3212 if (isa<FunctionNoProtoType>(FnType)) {
3213 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo);
3214 CalleeTy = CalleeTy->getPointerTo();
3215 Callee = Builder.CreateBitCast(Callee, CalleeTy, "callee.knr.cast");
3218 return EmitCall(FnInfo, Callee, ReturnValue, Args, TargetDecl);
3221 LValue CodeGenFunction::
3222 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
3224 if (E->getOpcode() == BO_PtrMemI)
3225 BaseV = EmitScalarExpr(E->getLHS());
3227 BaseV = EmitLValue(E->getLHS()).getAddress();
3229 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
3231 const MemberPointerType *MPT
3232 = E->getRHS()->getType()->getAs<MemberPointerType>();
3235 CGM.getCXXABI().EmitMemberDataPointerAddress(*this, BaseV, OffsetV, MPT);
3237 return MakeAddrLValue(AddV, MPT->getPointeeType());
3240 /// Given the address of a temporary variable, produce an r-value of
3242 RValue CodeGenFunction::convertTempToRValue(llvm::Value *addr,
3244 SourceLocation loc) {
3245 LValue lvalue = MakeNaturalAlignAddrLValue(addr, type);
3246 switch (getEvaluationKind(type)) {
3248 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc));
3250 return lvalue.asAggregateRValue();
3252 return RValue::get(EmitLoadOfScalar(lvalue, loc));
3254 llvm_unreachable("bad evaluation kind");
3257 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) {
3258 assert(Val->getType()->isFPOrFPVectorTy());
3259 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val))
3262 llvm::MDBuilder MDHelper(getLLVMContext());
3263 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy);
3265 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node);
3269 struct LValueOrRValue {
3275 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF,
3276 const PseudoObjectExpr *E,
3278 AggValueSlot slot) {
3279 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
3281 // Find the result expression, if any.
3282 const Expr *resultExpr = E->getResultExpr();
3283 LValueOrRValue result;
3285 for (PseudoObjectExpr::const_semantics_iterator
3286 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
3287 const Expr *semantic = *i;
3289 // If this semantic expression is an opaque value, bind it
3290 // to the result of its source expression.
3291 if (const OpaqueValueExpr *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
3293 // If this is the result expression, we may need to evaluate
3294 // directly into the slot.
3295 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
3297 if (ov == resultExpr && ov->isRValue() && !forLValue &&
3298 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) {
3299 CGF.EmitAggExpr(ov->getSourceExpr(), slot);
3301 LValue LV = CGF.MakeAddrLValue(slot.getAddr(), ov->getType());
3302 opaqueData = OVMA::bind(CGF, ov, LV);
3303 result.RV = slot.asRValue();
3305 // Otherwise, emit as normal.
3307 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
3309 // If this is the result, also evaluate the result now.
3310 if (ov == resultExpr) {
3312 result.LV = CGF.EmitLValue(ov);
3314 result.RV = CGF.EmitAnyExpr(ov, slot);
3318 opaques.push_back(opaqueData);
3320 // Otherwise, if the expression is the result, evaluate it
3321 // and remember the result.
3322 } else if (semantic == resultExpr) {
3324 result.LV = CGF.EmitLValue(semantic);
3326 result.RV = CGF.EmitAnyExpr(semantic, slot);
3328 // Otherwise, evaluate the expression in an ignored context.
3330 CGF.EmitIgnoredExpr(semantic);
3334 // Unbind all the opaques now.
3335 for (unsigned i = 0, e = opaques.size(); i != e; ++i)
3336 opaques[i].unbind(CGF);
3341 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E,
3342 AggValueSlot slot) {
3343 return emitPseudoObjectExpr(*this, E, false, slot).RV;
3346 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) {
3347 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV;