CGExprAgg.cpp revision 239462
1193326Sed//===--- CGExprAgg.cpp - Emit LLVM Code from Aggregate Expressions --------===// 2193326Sed// 3193326Sed// The LLVM Compiler Infrastructure 4193326Sed// 5193326Sed// This file is distributed under the University of Illinois Open Source 6193326Sed// License. See LICENSE.TXT for details. 7193326Sed// 8193326Sed//===----------------------------------------------------------------------===// 9193326Sed// 10193326Sed// This contains code to emit Aggregate Expr nodes as LLVM code. 11193326Sed// 12193326Sed//===----------------------------------------------------------------------===// 13193326Sed 14193326Sed#include "CodeGenFunction.h" 15193326Sed#include "CodeGenModule.h" 16198092Srdivacky#include "CGObjCRuntime.h" 17193326Sed#include "clang/AST/ASTContext.h" 18193326Sed#include "clang/AST/DeclCXX.h" 19234353Sdim#include "clang/AST/DeclTemplate.h" 20193326Sed#include "clang/AST/StmtVisitor.h" 21193326Sed#include "llvm/Constants.h" 22193326Sed#include "llvm/Function.h" 23193326Sed#include "llvm/GlobalVariable.h" 24193326Sed#include "llvm/Intrinsics.h" 25193326Sedusing namespace clang; 26193326Sedusing namespace CodeGen; 27193326Sed 28193326Sed//===----------------------------------------------------------------------===// 29193326Sed// Aggregate Expression Emitter 30193326Sed//===----------------------------------------------------------------------===// 31193326Sed 32193326Sednamespace { 33199990Srdivackyclass AggExprEmitter : public StmtVisitor<AggExprEmitter> { 34193326Sed CodeGenFunction &CGF; 35193326Sed CGBuilderTy &Builder; 36218893Sdim AggValueSlot Dest; 37208600Srdivacky 38226633Sdim /// We want to use 'dest' as the return slot except under two 39226633Sdim /// conditions: 40226633Sdim /// - The destination slot requires garbage collection, so we 41226633Sdim /// need to use the GC API. 42226633Sdim /// - The destination slot is potentially aliased. 43226633Sdim bool shouldUseDestForReturnSlot() const { 44226633Sdim return !(Dest.requiresGCollection() || Dest.isPotentiallyAliased()); 45226633Sdim } 46226633Sdim 47208600Srdivacky ReturnValueSlot getReturnValueSlot() const { 48226633Sdim if (!shouldUseDestForReturnSlot()) 49226633Sdim return ReturnValueSlot(); 50208600Srdivacky 51218893Sdim return ReturnValueSlot(Dest.getAddr(), Dest.isVolatile()); 52208600Srdivacky } 53208600Srdivacky 54218893Sdim AggValueSlot EnsureSlot(QualType T) { 55218893Sdim if (!Dest.isIgnored()) return Dest; 56218893Sdim return CGF.CreateAggTemp(T, "agg.tmp.ensured"); 57218893Sdim } 58239462Sdim void EnsureDest(QualType T) { 59239462Sdim if (!Dest.isIgnored()) return; 60239462Sdim Dest = CGF.CreateAggTemp(T, "agg.tmp.ensured"); 61239462Sdim } 62218893Sdim 63193326Sedpublic: 64239462Sdim AggExprEmitter(CodeGenFunction &cgf, AggValueSlot Dest) 65239462Sdim : CGF(cgf), Builder(CGF.Builder), Dest(Dest) { 66193326Sed } 67193326Sed 68193326Sed //===--------------------------------------------------------------------===// 69193326Sed // Utilities 70193326Sed //===--------------------------------------------------------------------===// 71193326Sed 72193326Sed /// EmitAggLoadOfLValue - Given an expression with aggregate type that 73193326Sed /// represents a value lvalue, this method emits the address of the lvalue, 74193326Sed /// then loads the result into DestPtr. 75193326Sed void EmitAggLoadOfLValue(const Expr *E); 76193326Sed 77193326Sed /// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired. 78239462Sdim void EmitFinalDestCopy(QualType type, const LValue &src); 79239462Sdim void EmitFinalDestCopy(QualType type, RValue src, 80239462Sdim CharUnits srcAlignment = CharUnits::Zero()); 81239462Sdim void EmitCopy(QualType type, const AggValueSlot &dest, 82239462Sdim const AggValueSlot &src); 83193326Sed 84226633Sdim void EmitMoveFromReturnSlot(const Expr *E, RValue Src); 85208600Srdivacky 86234353Sdim void EmitStdInitializerList(llvm::Value *DestPtr, InitListExpr *InitList); 87234353Sdim void EmitArrayInit(llvm::Value *DestPtr, llvm::ArrayType *AType, 88234353Sdim QualType elementType, InitListExpr *E); 89234353Sdim 90226633Sdim AggValueSlot::NeedsGCBarriers_t needsGC(QualType T) { 91234353Sdim if (CGF.getLangOpts().getGC() && TypeRequiresGCollection(T)) 92226633Sdim return AggValueSlot::NeedsGCBarriers; 93226633Sdim return AggValueSlot::DoesNotNeedGCBarriers; 94226633Sdim } 95226633Sdim 96208600Srdivacky bool TypeRequiresGCollection(QualType T); 97208600Srdivacky 98193326Sed //===--------------------------------------------------------------------===// 99193326Sed // Visitor Methods 100193326Sed //===--------------------------------------------------------------------===// 101198092Srdivacky 102193326Sed void VisitStmt(Stmt *S) { 103193326Sed CGF.ErrorUnsupported(S, "aggregate expression"); 104193326Sed } 105193326Sed void VisitParenExpr(ParenExpr *PE) { Visit(PE->getSubExpr()); } 106221345Sdim void VisitGenericSelectionExpr(GenericSelectionExpr *GE) { 107221345Sdim Visit(GE->getResultExpr()); 108221345Sdim } 109193326Sed void VisitUnaryExtension(UnaryOperator *E) { Visit(E->getSubExpr()); } 110224145Sdim void VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *E) { 111224145Sdim return Visit(E->getReplacement()); 112224145Sdim } 113193326Sed 114193326Sed // l-values. 115234353Sdim void VisitDeclRefExpr(DeclRefExpr *E) { 116234353Sdim // For aggregates, we should always be able to emit the variable 117234353Sdim // as an l-value unless it's a reference. This is due to the fact 118234353Sdim // that we can't actually ever see a normal l2r conversion on an 119234353Sdim // aggregate in C++, and in C there's no language standard 120234353Sdim // actively preventing us from listing variables in the captures 121234353Sdim // list of a block. 122234353Sdim if (E->getDecl()->getType()->isReferenceType()) { 123234353Sdim if (CodeGenFunction::ConstantEmission result 124234353Sdim = CGF.tryEmitAsConstant(E)) { 125239462Sdim EmitFinalDestCopy(E->getType(), result.getReferenceLValue(CGF, E)); 126234353Sdim return; 127234353Sdim } 128234353Sdim } 129234353Sdim 130234353Sdim EmitAggLoadOfLValue(E); 131234353Sdim } 132234353Sdim 133193326Sed void VisitMemberExpr(MemberExpr *ME) { EmitAggLoadOfLValue(ME); } 134193326Sed void VisitUnaryDeref(UnaryOperator *E) { EmitAggLoadOfLValue(E); } 135193326Sed void VisitStringLiteral(StringLiteral *E) { EmitAggLoadOfLValue(E); } 136224145Sdim void VisitCompoundLiteralExpr(CompoundLiteralExpr *E); 137193326Sed void VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 138193326Sed EmitAggLoadOfLValue(E); 139193326Sed } 140193326Sed void VisitPredefinedExpr(const PredefinedExpr *E) { 141198092Srdivacky EmitAggLoadOfLValue(E); 142193326Sed } 143198092Srdivacky 144193326Sed // Operators. 145198092Srdivacky void VisitCastExpr(CastExpr *E); 146193326Sed void VisitCallExpr(const CallExpr *E); 147193326Sed void VisitStmtExpr(const StmtExpr *E); 148193326Sed void VisitBinaryOperator(const BinaryOperator *BO); 149198398Srdivacky void VisitPointerToDataMemberBinaryOperator(const BinaryOperator *BO); 150193326Sed void VisitBinAssign(const BinaryOperator *E); 151193326Sed void VisitBinComma(const BinaryOperator *E); 152193326Sed 153193326Sed void VisitObjCMessageExpr(ObjCMessageExpr *E); 154193326Sed void VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 155193326Sed EmitAggLoadOfLValue(E); 156193326Sed } 157198092Srdivacky 158218893Sdim void VisitAbstractConditionalOperator(const AbstractConditionalOperator *CO); 159198092Srdivacky void VisitChooseExpr(const ChooseExpr *CE); 160193326Sed void VisitInitListExpr(InitListExpr *E); 161201361Srdivacky void VisitImplicitValueInitExpr(ImplicitValueInitExpr *E); 162193326Sed void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 163193326Sed Visit(DAE->getExpr()); 164193326Sed } 165193326Sed void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E); 166193326Sed void VisitCXXConstructExpr(const CXXConstructExpr *E); 167234353Sdim void VisitLambdaExpr(LambdaExpr *E); 168218893Sdim void VisitExprWithCleanups(ExprWithCleanups *E); 169210299Sed void VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E); 170199482Srdivacky void VisitCXXTypeidExpr(CXXTypeidExpr *E) { EmitAggLoadOfLValue(E); } 171224145Sdim void VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E); 172218893Sdim void VisitOpaqueValueExpr(OpaqueValueExpr *E); 173218893Sdim 174234353Sdim void VisitPseudoObjectExpr(PseudoObjectExpr *E) { 175234353Sdim if (E->isGLValue()) { 176234353Sdim LValue LV = CGF.EmitPseudoObjectLValue(E); 177239462Sdim return EmitFinalDestCopy(E->getType(), LV); 178234353Sdim } 179234353Sdim 180234353Sdim CGF.EmitPseudoObjectRValue(E, EnsureSlot(E->getType())); 181234353Sdim } 182234353Sdim 183193326Sed void VisitVAArgExpr(VAArgExpr *E); 184193326Sed 185224145Sdim void EmitInitializationToLValue(Expr *E, LValue Address); 186224145Sdim void EmitNullInitializationToLValue(LValue Address); 187193326Sed // case Expr::ChooseExprClass: 188200583Srdivacky void VisitCXXThrowExpr(const CXXThrowExpr *E) { CGF.EmitCXXThrowExpr(E); } 189226633Sdim void VisitAtomicExpr(AtomicExpr *E) { 190226633Sdim CGF.EmitAtomicExpr(E, EnsureSlot(E->getType()).getAddr()); 191226633Sdim } 192193326Sed}; 193193326Sed} // end anonymous namespace. 194193326Sed 195193326Sed//===----------------------------------------------------------------------===// 196193326Sed// Utilities 197193326Sed//===----------------------------------------------------------------------===// 198193326Sed 199193326Sed/// EmitAggLoadOfLValue - Given an expression with aggregate type that 200193326Sed/// represents a value lvalue, this method emits the address of the lvalue, 201193326Sed/// then loads the result into DestPtr. 202193326Sedvoid AggExprEmitter::EmitAggLoadOfLValue(const Expr *E) { 203193326Sed LValue LV = CGF.EmitLValue(E); 204239462Sdim EmitFinalDestCopy(E->getType(), LV); 205193326Sed} 206193326Sed 207208600Srdivacky/// \brief True if the given aggregate type requires special GC API calls. 208208600Srdivackybool AggExprEmitter::TypeRequiresGCollection(QualType T) { 209208600Srdivacky // Only record types have members that might require garbage collection. 210208600Srdivacky const RecordType *RecordTy = T->getAs<RecordType>(); 211208600Srdivacky if (!RecordTy) return false; 212208600Srdivacky 213208600Srdivacky // Don't mess with non-trivial C++ types. 214208600Srdivacky RecordDecl *Record = RecordTy->getDecl(); 215208600Srdivacky if (isa<CXXRecordDecl>(Record) && 216208600Srdivacky (!cast<CXXRecordDecl>(Record)->hasTrivialCopyConstructor() || 217208600Srdivacky !cast<CXXRecordDecl>(Record)->hasTrivialDestructor())) 218208600Srdivacky return false; 219208600Srdivacky 220208600Srdivacky // Check whether the type has an object member. 221208600Srdivacky return Record->hasObjectMember(); 222208600Srdivacky} 223208600Srdivacky 224226633Sdim/// \brief Perform the final move to DestPtr if for some reason 225226633Sdim/// getReturnValueSlot() didn't use it directly. 226208600Srdivacky/// 227208600Srdivacky/// The idea is that you do something like this: 228208600Srdivacky/// RValue Result = EmitSomething(..., getReturnValueSlot()); 229226633Sdim/// EmitMoveFromReturnSlot(E, Result); 230226633Sdim/// 231226633Sdim/// If nothing interferes, this will cause the result to be emitted 232226633Sdim/// directly into the return value slot. Otherwise, a final move 233226633Sdim/// will be performed. 234239462Sdimvoid AggExprEmitter::EmitMoveFromReturnSlot(const Expr *E, RValue src) { 235226633Sdim if (shouldUseDestForReturnSlot()) { 236226633Sdim // Logically, Dest.getAddr() should equal Src.getAggregateAddr(). 237226633Sdim // The possibility of undef rvalues complicates that a lot, 238226633Sdim // though, so we can't really assert. 239226633Sdim return; 240210299Sed } 241226633Sdim 242239462Sdim // Otherwise, copy from there to the destination. 243239462Sdim assert(Dest.getAddr() != src.getAggregateAddr()); 244239462Sdim std::pair<CharUnits, CharUnits> typeInfo = 245234982Sdim CGF.getContext().getTypeInfoInChars(E->getType()); 246239462Sdim EmitFinalDestCopy(E->getType(), src, typeInfo.second); 247208600Srdivacky} 248208600Srdivacky 249193326Sed/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired. 250239462Sdimvoid AggExprEmitter::EmitFinalDestCopy(QualType type, RValue src, 251239462Sdim CharUnits srcAlign) { 252239462Sdim assert(src.isAggregate() && "value must be aggregate value!"); 253239462Sdim LValue srcLV = CGF.MakeAddrLValue(src.getAggregateAddr(), type, srcAlign); 254239462Sdim EmitFinalDestCopy(type, srcLV); 255239462Sdim} 256193326Sed 257239462Sdim/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired. 258239462Sdimvoid AggExprEmitter::EmitFinalDestCopy(QualType type, const LValue &src) { 259218893Sdim // If Dest is ignored, then we're evaluating an aggregate expression 260239462Sdim // in a context that doesn't care about the result. Note that loads 261239462Sdim // from volatile l-values force the existence of a non-ignored 262239462Sdim // destination. 263239462Sdim if (Dest.isIgnored()) 264239462Sdim return; 265212904Sdim 266239462Sdim AggValueSlot srcAgg = 267239462Sdim AggValueSlot::forLValue(src, AggValueSlot::IsDestructed, 268239462Sdim needsGC(type), AggValueSlot::IsAliased); 269239462Sdim EmitCopy(type, Dest, srcAgg); 270239462Sdim} 271193326Sed 272239462Sdim/// Perform a copy from the source into the destination. 273239462Sdim/// 274239462Sdim/// \param type - the type of the aggregate being copied; qualifiers are 275239462Sdim/// ignored 276239462Sdimvoid AggExprEmitter::EmitCopy(QualType type, const AggValueSlot &dest, 277239462Sdim const AggValueSlot &src) { 278239462Sdim if (dest.requiresGCollection()) { 279239462Sdim CharUnits sz = CGF.getContext().getTypeSizeInChars(type); 280239462Sdim llvm::Value *size = llvm::ConstantInt::get(CGF.SizeTy, sz.getQuantity()); 281198092Srdivacky CGF.CGM.getObjCRuntime().EmitGCMemmoveCollectable(CGF, 282239462Sdim dest.getAddr(), 283239462Sdim src.getAddr(), 284239462Sdim size); 285198092Srdivacky return; 286198092Srdivacky } 287239462Sdim 288193326Sed // If the result of the assignment is used, copy the LHS there also. 289239462Sdim // It's volatile if either side is. Use the minimum alignment of 290239462Sdim // the two sides. 291239462Sdim CGF.EmitAggregateCopy(dest.getAddr(), src.getAddr(), type, 292239462Sdim dest.isVolatile() || src.isVolatile(), 293239462Sdim std::min(dest.getAlignment(), src.getAlignment())); 294193326Sed} 295193326Sed 296234353Sdimstatic QualType GetStdInitializerListElementType(QualType T) { 297234353Sdim // Just assume that this is really std::initializer_list. 298234353Sdim ClassTemplateSpecializationDecl *specialization = 299234353Sdim cast<ClassTemplateSpecializationDecl>(T->castAs<RecordType>()->getDecl()); 300234353Sdim return specialization->getTemplateArgs()[0].getAsType(); 301234353Sdim} 302234353Sdim 303234353Sdim/// \brief Prepare cleanup for the temporary array. 304234353Sdimstatic void EmitStdInitializerListCleanup(CodeGenFunction &CGF, 305234353Sdim QualType arrayType, 306234353Sdim llvm::Value *addr, 307234353Sdim const InitListExpr *initList) { 308234353Sdim QualType::DestructionKind dtorKind = arrayType.isDestructedType(); 309234353Sdim if (!dtorKind) 310234353Sdim return; // Type doesn't need destroying. 311234353Sdim if (dtorKind != QualType::DK_cxx_destructor) { 312234353Sdim CGF.ErrorUnsupported(initList, "ObjC ARC type in initializer_list"); 313234353Sdim return; 314234353Sdim } 315234353Sdim 316234353Sdim CodeGenFunction::Destroyer *destroyer = CGF.getDestroyer(dtorKind); 317234353Sdim CGF.pushDestroy(NormalAndEHCleanup, addr, arrayType, destroyer, 318234353Sdim /*EHCleanup=*/true); 319234353Sdim} 320234353Sdim 321234353Sdim/// \brief Emit the initializer for a std::initializer_list initialized with a 322234353Sdim/// real initializer list. 323234353Sdimvoid AggExprEmitter::EmitStdInitializerList(llvm::Value *destPtr, 324234353Sdim InitListExpr *initList) { 325234353Sdim // We emit an array containing the elements, then have the init list point 326234353Sdim // at the array. 327234353Sdim ASTContext &ctx = CGF.getContext(); 328234353Sdim unsigned numInits = initList->getNumInits(); 329234353Sdim QualType element = GetStdInitializerListElementType(initList->getType()); 330234353Sdim llvm::APInt size(ctx.getTypeSize(ctx.getSizeType()), numInits); 331234353Sdim QualType array = ctx.getConstantArrayType(element, size, ArrayType::Normal,0); 332234353Sdim llvm::Type *LTy = CGF.ConvertTypeForMem(array); 333234353Sdim llvm::AllocaInst *alloc = CGF.CreateTempAlloca(LTy); 334234353Sdim alloc->setAlignment(ctx.getTypeAlignInChars(array).getQuantity()); 335234353Sdim alloc->setName(".initlist."); 336234353Sdim 337234353Sdim EmitArrayInit(alloc, cast<llvm::ArrayType>(LTy), element, initList); 338234353Sdim 339234353Sdim // FIXME: The diagnostics are somewhat out of place here. 340234353Sdim RecordDecl *record = initList->getType()->castAs<RecordType>()->getDecl(); 341234353Sdim RecordDecl::field_iterator field = record->field_begin(); 342234353Sdim if (field == record->field_end()) { 343234353Sdim CGF.ErrorUnsupported(initList, "weird std::initializer_list"); 344234353Sdim return; 345234353Sdim } 346234353Sdim 347234353Sdim QualType elementPtr = ctx.getPointerType(element.withConst()); 348234353Sdim 349234353Sdim // Start pointer. 350234353Sdim if (!ctx.hasSameType(field->getType(), elementPtr)) { 351234353Sdim CGF.ErrorUnsupported(initList, "weird std::initializer_list"); 352234353Sdim return; 353234353Sdim } 354234982Sdim LValue DestLV = CGF.MakeNaturalAlignAddrLValue(destPtr, initList->getType()); 355234982Sdim LValue start = CGF.EmitLValueForFieldInitialization(DestLV, *field); 356234353Sdim llvm::Value *arrayStart = Builder.CreateStructGEP(alloc, 0, "arraystart"); 357234353Sdim CGF.EmitStoreThroughLValue(RValue::get(arrayStart), start); 358234353Sdim ++field; 359234353Sdim 360234353Sdim if (field == record->field_end()) { 361234353Sdim CGF.ErrorUnsupported(initList, "weird std::initializer_list"); 362234353Sdim return; 363234353Sdim } 364234982Sdim LValue endOrLength = CGF.EmitLValueForFieldInitialization(DestLV, *field); 365234353Sdim if (ctx.hasSameType(field->getType(), elementPtr)) { 366234353Sdim // End pointer. 367234353Sdim llvm::Value *arrayEnd = Builder.CreateStructGEP(alloc,numInits, "arrayend"); 368234353Sdim CGF.EmitStoreThroughLValue(RValue::get(arrayEnd), endOrLength); 369234353Sdim } else if(ctx.hasSameType(field->getType(), ctx.getSizeType())) { 370234353Sdim // Length. 371234353Sdim CGF.EmitStoreThroughLValue(RValue::get(Builder.getInt(size)), endOrLength); 372234353Sdim } else { 373234353Sdim CGF.ErrorUnsupported(initList, "weird std::initializer_list"); 374234353Sdim return; 375234353Sdim } 376234353Sdim 377234353Sdim if (!Dest.isExternallyDestructed()) 378234353Sdim EmitStdInitializerListCleanup(CGF, array, alloc, initList); 379234353Sdim} 380234353Sdim 381234353Sdim/// \brief Emit initialization of an array from an initializer list. 382234353Sdimvoid AggExprEmitter::EmitArrayInit(llvm::Value *DestPtr, llvm::ArrayType *AType, 383234353Sdim QualType elementType, InitListExpr *E) { 384234353Sdim uint64_t NumInitElements = E->getNumInits(); 385234353Sdim 386234353Sdim uint64_t NumArrayElements = AType->getNumElements(); 387234353Sdim assert(NumInitElements <= NumArrayElements); 388234353Sdim 389234353Sdim // DestPtr is an array*. Construct an elementType* by drilling 390234353Sdim // down a level. 391234353Sdim llvm::Value *zero = llvm::ConstantInt::get(CGF.SizeTy, 0); 392234353Sdim llvm::Value *indices[] = { zero, zero }; 393234353Sdim llvm::Value *begin = 394234353Sdim Builder.CreateInBoundsGEP(DestPtr, indices, "arrayinit.begin"); 395234353Sdim 396234353Sdim // Exception safety requires us to destroy all the 397234353Sdim // already-constructed members if an initializer throws. 398234353Sdim // For that, we'll need an EH cleanup. 399234353Sdim QualType::DestructionKind dtorKind = elementType.isDestructedType(); 400234353Sdim llvm::AllocaInst *endOfInit = 0; 401234353Sdim EHScopeStack::stable_iterator cleanup; 402234353Sdim llvm::Instruction *cleanupDominator = 0; 403234353Sdim if (CGF.needsEHCleanup(dtorKind)) { 404234353Sdim // In principle we could tell the cleanup where we are more 405234353Sdim // directly, but the control flow can get so varied here that it 406234353Sdim // would actually be quite complex. Therefore we go through an 407234353Sdim // alloca. 408234353Sdim endOfInit = CGF.CreateTempAlloca(begin->getType(), 409234353Sdim "arrayinit.endOfInit"); 410234353Sdim cleanupDominator = Builder.CreateStore(begin, endOfInit); 411234353Sdim CGF.pushIrregularPartialArrayCleanup(begin, endOfInit, elementType, 412234353Sdim CGF.getDestroyer(dtorKind)); 413234353Sdim cleanup = CGF.EHStack.stable_begin(); 414234353Sdim 415234353Sdim // Otherwise, remember that we didn't need a cleanup. 416234353Sdim } else { 417234353Sdim dtorKind = QualType::DK_none; 418234353Sdim } 419234353Sdim 420234353Sdim llvm::Value *one = llvm::ConstantInt::get(CGF.SizeTy, 1); 421234353Sdim 422234353Sdim // The 'current element to initialize'. The invariants on this 423234353Sdim // variable are complicated. Essentially, after each iteration of 424234353Sdim // the loop, it points to the last initialized element, except 425234353Sdim // that it points to the beginning of the array before any 426234353Sdim // elements have been initialized. 427234353Sdim llvm::Value *element = begin; 428234353Sdim 429234353Sdim // Emit the explicit initializers. 430234353Sdim for (uint64_t i = 0; i != NumInitElements; ++i) { 431234353Sdim // Advance to the next element. 432234353Sdim if (i > 0) { 433234353Sdim element = Builder.CreateInBoundsGEP(element, one, "arrayinit.element"); 434234353Sdim 435234353Sdim // Tell the cleanup that it needs to destroy up to this 436234353Sdim // element. TODO: some of these stores can be trivially 437234353Sdim // observed to be unnecessary. 438234353Sdim if (endOfInit) Builder.CreateStore(element, endOfInit); 439234353Sdim } 440234353Sdim 441234353Sdim // If these are nested std::initializer_list inits, do them directly, 442234353Sdim // because they are conceptually the same "location". 443234353Sdim InitListExpr *initList = dyn_cast<InitListExpr>(E->getInit(i)); 444234353Sdim if (initList && initList->initializesStdInitializerList()) { 445234353Sdim EmitStdInitializerList(element, initList); 446234353Sdim } else { 447234353Sdim LValue elementLV = CGF.MakeAddrLValue(element, elementType); 448234353Sdim EmitInitializationToLValue(E->getInit(i), elementLV); 449234353Sdim } 450234353Sdim } 451234353Sdim 452234353Sdim // Check whether there's a non-trivial array-fill expression. 453234353Sdim // Note that this will be a CXXConstructExpr even if the element 454234353Sdim // type is an array (or array of array, etc.) of class type. 455234353Sdim Expr *filler = E->getArrayFiller(); 456234353Sdim bool hasTrivialFiller = true; 457234353Sdim if (CXXConstructExpr *cons = dyn_cast_or_null<CXXConstructExpr>(filler)) { 458234353Sdim assert(cons->getConstructor()->isDefaultConstructor()); 459234353Sdim hasTrivialFiller = cons->getConstructor()->isTrivial(); 460234353Sdim } 461234353Sdim 462234353Sdim // Any remaining elements need to be zero-initialized, possibly 463234353Sdim // using the filler expression. We can skip this if the we're 464234353Sdim // emitting to zeroed memory. 465234353Sdim if (NumInitElements != NumArrayElements && 466234353Sdim !(Dest.isZeroed() && hasTrivialFiller && 467234353Sdim CGF.getTypes().isZeroInitializable(elementType))) { 468234353Sdim 469234353Sdim // Use an actual loop. This is basically 470234353Sdim // do { *array++ = filler; } while (array != end); 471234353Sdim 472234353Sdim // Advance to the start of the rest of the array. 473234353Sdim if (NumInitElements) { 474234353Sdim element = Builder.CreateInBoundsGEP(element, one, "arrayinit.start"); 475234353Sdim if (endOfInit) Builder.CreateStore(element, endOfInit); 476234353Sdim } 477234353Sdim 478234353Sdim // Compute the end of the array. 479234353Sdim llvm::Value *end = Builder.CreateInBoundsGEP(begin, 480234353Sdim llvm::ConstantInt::get(CGF.SizeTy, NumArrayElements), 481234353Sdim "arrayinit.end"); 482234353Sdim 483234353Sdim llvm::BasicBlock *entryBB = Builder.GetInsertBlock(); 484234353Sdim llvm::BasicBlock *bodyBB = CGF.createBasicBlock("arrayinit.body"); 485234353Sdim 486234353Sdim // Jump into the body. 487234353Sdim CGF.EmitBlock(bodyBB); 488234353Sdim llvm::PHINode *currentElement = 489234353Sdim Builder.CreatePHI(element->getType(), 2, "arrayinit.cur"); 490234353Sdim currentElement->addIncoming(element, entryBB); 491234353Sdim 492234353Sdim // Emit the actual filler expression. 493234353Sdim LValue elementLV = CGF.MakeAddrLValue(currentElement, elementType); 494234353Sdim if (filler) 495234353Sdim EmitInitializationToLValue(filler, elementLV); 496234353Sdim else 497234353Sdim EmitNullInitializationToLValue(elementLV); 498234353Sdim 499234353Sdim // Move on to the next element. 500234353Sdim llvm::Value *nextElement = 501234353Sdim Builder.CreateInBoundsGEP(currentElement, one, "arrayinit.next"); 502234353Sdim 503234353Sdim // Tell the EH cleanup that we finished with the last element. 504234353Sdim if (endOfInit) Builder.CreateStore(nextElement, endOfInit); 505234353Sdim 506234353Sdim // Leave the loop if we're done. 507234353Sdim llvm::Value *done = Builder.CreateICmpEQ(nextElement, end, 508234353Sdim "arrayinit.done"); 509234353Sdim llvm::BasicBlock *endBB = CGF.createBasicBlock("arrayinit.end"); 510234353Sdim Builder.CreateCondBr(done, endBB, bodyBB); 511234353Sdim currentElement->addIncoming(nextElement, Builder.GetInsertBlock()); 512234353Sdim 513234353Sdim CGF.EmitBlock(endBB); 514234353Sdim } 515234353Sdim 516234353Sdim // Leave the partial-array cleanup if we entered one. 517234353Sdim if (dtorKind) CGF.DeactivateCleanupBlock(cleanup, cleanupDominator); 518234353Sdim} 519234353Sdim 520193326Sed//===----------------------------------------------------------------------===// 521193326Sed// Visitor Methods 522193326Sed//===----------------------------------------------------------------------===// 523193326Sed 524224145Sdimvoid AggExprEmitter::VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E){ 525224145Sdim Visit(E->GetTemporaryExpr()); 526224145Sdim} 527224145Sdim 528218893Sdimvoid AggExprEmitter::VisitOpaqueValueExpr(OpaqueValueExpr *e) { 529239462Sdim EmitFinalDestCopy(e->getType(), CGF.getOpaqueLValueMapping(e)); 530218893Sdim} 531218893Sdim 532224145Sdimvoid 533224145SdimAggExprEmitter::VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 534224145Sdim if (E->getType().isPODType(CGF.getContext())) { 535224145Sdim // For a POD type, just emit a load of the lvalue + a copy, because our 536224145Sdim // compound literal might alias the destination. 537224145Sdim // FIXME: This is a band-aid; the real problem appears to be in our handling 538224145Sdim // of assignments, where we store directly into the LHS without checking 539224145Sdim // whether anything in the RHS aliases. 540224145Sdim EmitAggLoadOfLValue(E); 541224145Sdim return; 542224145Sdim } 543224145Sdim 544224145Sdim AggValueSlot Slot = EnsureSlot(E->getType()); 545224145Sdim CGF.EmitAggExpr(E->getInitializer(), Slot); 546224145Sdim} 547224145Sdim 548224145Sdim 549198092Srdivackyvoid AggExprEmitter::VisitCastExpr(CastExpr *E) { 550198092Srdivacky switch (E->getCastKind()) { 551212904Sdim case CK_Dynamic: { 552208600Srdivacky assert(isa<CXXDynamicCastExpr>(E) && "CK_Dynamic without a dynamic_cast?"); 553208600Srdivacky LValue LV = CGF.EmitCheckedLValue(E->getSubExpr()); 554208600Srdivacky // FIXME: Do we also need to handle property references here? 555208600Srdivacky if (LV.isSimple()) 556208600Srdivacky CGF.EmitDynamicCast(LV.getAddress(), cast<CXXDynamicCastExpr>(E)); 557208600Srdivacky else 558208600Srdivacky CGF.CGM.ErrorUnsupported(E, "non-simple lvalue dynamic_cast"); 559208600Srdivacky 560218893Sdim if (!Dest.isIgnored()) 561218893Sdim CGF.CGM.ErrorUnsupported(E, "lvalue dynamic_cast with a destination"); 562208600Srdivacky break; 563208600Srdivacky } 564208600Srdivacky 565212904Sdim case CK_ToUnion: { 566221345Sdim if (Dest.isIgnored()) break; 567221345Sdim 568198092Srdivacky // GCC union extension 569212904Sdim QualType Ty = E->getSubExpr()->getType(); 570212904Sdim QualType PtrTy = CGF.getContext().getPointerType(Ty); 571218893Sdim llvm::Value *CastPtr = Builder.CreateBitCast(Dest.getAddr(), 572193401Sed CGF.ConvertType(PtrTy)); 573224145Sdim EmitInitializationToLValue(E->getSubExpr(), 574224145Sdim CGF.MakeAddrLValue(CastPtr, Ty)); 575198092Srdivacky break; 576193326Sed } 577193326Sed 578212904Sdim case CK_DerivedToBase: 579212904Sdim case CK_BaseToDerived: 580212904Sdim case CK_UncheckedDerivedToBase: { 581226633Sdim llvm_unreachable("cannot perform hierarchy conversion in EmitAggExpr: " 582208600Srdivacky "should have been unpacked before we got here"); 583208600Srdivacky } 584208600Srdivacky 585239462Sdim case CK_LValueToRValue: 586239462Sdim // If we're loading from a volatile type, force the destination 587239462Sdim // into existence. 588239462Sdim if (E->getSubExpr()->getType().isVolatileQualified()) { 589239462Sdim EnsureDest(E->getType()); 590239462Sdim return Visit(E->getSubExpr()); 591239462Sdim } 592239462Sdim // fallthrough 593239462Sdim 594212904Sdim case CK_NoOp: 595234353Sdim case CK_AtomicToNonAtomic: 596234353Sdim case CK_NonAtomicToAtomic: 597212904Sdim case CK_UserDefinedConversion: 598212904Sdim case CK_ConstructorConversion: 599198092Srdivacky assert(CGF.getContext().hasSameUnqualifiedType(E->getSubExpr()->getType(), 600198092Srdivacky E->getType()) && 601198092Srdivacky "Implicit cast types must be compatible"); 602198092Srdivacky Visit(E->getSubExpr()); 603198092Srdivacky break; 604218893Sdim 605212904Sdim case CK_LValueBitCast: 606218893Sdim llvm_unreachable("should not be emitting lvalue bitcast as rvalue"); 607221345Sdim 608218893Sdim case CK_Dependent: 609218893Sdim case CK_BitCast: 610218893Sdim case CK_ArrayToPointerDecay: 611218893Sdim case CK_FunctionToPointerDecay: 612218893Sdim case CK_NullToPointer: 613218893Sdim case CK_NullToMemberPointer: 614218893Sdim case CK_BaseToDerivedMemberPointer: 615218893Sdim case CK_DerivedToBaseMemberPointer: 616218893Sdim case CK_MemberPointerToBoolean: 617234353Sdim case CK_ReinterpretMemberPointer: 618218893Sdim case CK_IntegralToPointer: 619218893Sdim case CK_PointerToIntegral: 620218893Sdim case CK_PointerToBoolean: 621218893Sdim case CK_ToVoid: 622218893Sdim case CK_VectorSplat: 623218893Sdim case CK_IntegralCast: 624218893Sdim case CK_IntegralToBoolean: 625218893Sdim case CK_IntegralToFloating: 626218893Sdim case CK_FloatingToIntegral: 627218893Sdim case CK_FloatingToBoolean: 628218893Sdim case CK_FloatingCast: 629226633Sdim case CK_CPointerToObjCPointerCast: 630226633Sdim case CK_BlockPointerToObjCPointerCast: 631218893Sdim case CK_AnyPointerToBlockPointerCast: 632218893Sdim case CK_ObjCObjectLValueCast: 633218893Sdim case CK_FloatingRealToComplex: 634218893Sdim case CK_FloatingComplexToReal: 635218893Sdim case CK_FloatingComplexToBoolean: 636218893Sdim case CK_FloatingComplexCast: 637218893Sdim case CK_FloatingComplexToIntegralComplex: 638218893Sdim case CK_IntegralRealToComplex: 639218893Sdim case CK_IntegralComplexToReal: 640218893Sdim case CK_IntegralComplexToBoolean: 641218893Sdim case CK_IntegralComplexCast: 642218893Sdim case CK_IntegralComplexToFloatingComplex: 643226633Sdim case CK_ARCProduceObject: 644226633Sdim case CK_ARCConsumeObject: 645226633Sdim case CK_ARCReclaimReturnedObject: 646226633Sdim case CK_ARCExtendBlockObject: 647234353Sdim case CK_CopyAndAutoreleaseBlockObject: 648218893Sdim llvm_unreachable("cast kind invalid for aggregate types"); 649198398Srdivacky } 650193326Sed} 651193326Sed 652193326Sedvoid AggExprEmitter::VisitCallExpr(const CallExpr *E) { 653193326Sed if (E->getCallReturnType()->isReferenceType()) { 654193326Sed EmitAggLoadOfLValue(E); 655193326Sed return; 656193326Sed } 657198092Srdivacky 658208600Srdivacky RValue RV = CGF.EmitCallExpr(E, getReturnValueSlot()); 659226633Sdim EmitMoveFromReturnSlot(E, RV); 660193326Sed} 661193326Sed 662193326Sedvoid AggExprEmitter::VisitObjCMessageExpr(ObjCMessageExpr *E) { 663208600Srdivacky RValue RV = CGF.EmitObjCMessageExpr(E, getReturnValueSlot()); 664226633Sdim EmitMoveFromReturnSlot(E, RV); 665193326Sed} 666193326Sed 667193326Sedvoid AggExprEmitter::VisitBinComma(const BinaryOperator *E) { 668218893Sdim CGF.EmitIgnoredExpr(E->getLHS()); 669218893Sdim Visit(E->getRHS()); 670193326Sed} 671193326Sed 672193326Sedvoid AggExprEmitter::VisitStmtExpr(const StmtExpr *E) { 673218893Sdim CodeGenFunction::StmtExprEvaluation eval(CGF); 674218893Sdim CGF.EmitCompoundStmt(*E->getSubStmt(), true, Dest); 675193326Sed} 676193326Sed 677193326Sedvoid AggExprEmitter::VisitBinaryOperator(const BinaryOperator *E) { 678212904Sdim if (E->getOpcode() == BO_PtrMemD || E->getOpcode() == BO_PtrMemI) 679198398Srdivacky VisitPointerToDataMemberBinaryOperator(E); 680198398Srdivacky else 681198398Srdivacky CGF.ErrorUnsupported(E, "aggregate binary expression"); 682193326Sed} 683193326Sed 684198398Srdivackyvoid AggExprEmitter::VisitPointerToDataMemberBinaryOperator( 685198398Srdivacky const BinaryOperator *E) { 686198398Srdivacky LValue LV = CGF.EmitPointerToDataMemberBinaryExpr(E); 687239462Sdim EmitFinalDestCopy(E->getType(), LV); 688198398Srdivacky} 689198398Srdivacky 690239462Sdim/// Is the value of the given expression possibly a reference to or 691239462Sdim/// into a __block variable? 692239462Sdimstatic bool isBlockVarRef(const Expr *E) { 693239462Sdim // Make sure we look through parens. 694239462Sdim E = E->IgnoreParens(); 695239462Sdim 696239462Sdim // Check for a direct reference to a __block variable. 697239462Sdim if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) { 698239462Sdim const VarDecl *var = dyn_cast<VarDecl>(DRE->getDecl()); 699239462Sdim return (var && var->hasAttr<BlocksAttr>()); 700239462Sdim } 701239462Sdim 702239462Sdim // More complicated stuff. 703239462Sdim 704239462Sdim // Binary operators. 705239462Sdim if (const BinaryOperator *op = dyn_cast<BinaryOperator>(E)) { 706239462Sdim // For an assignment or pointer-to-member operation, just care 707239462Sdim // about the LHS. 708239462Sdim if (op->isAssignmentOp() || op->isPtrMemOp()) 709239462Sdim return isBlockVarRef(op->getLHS()); 710239462Sdim 711239462Sdim // For a comma, just care about the RHS. 712239462Sdim if (op->getOpcode() == BO_Comma) 713239462Sdim return isBlockVarRef(op->getRHS()); 714239462Sdim 715239462Sdim // FIXME: pointer arithmetic? 716239462Sdim return false; 717239462Sdim 718239462Sdim // Check both sides of a conditional operator. 719239462Sdim } else if (const AbstractConditionalOperator *op 720239462Sdim = dyn_cast<AbstractConditionalOperator>(E)) { 721239462Sdim return isBlockVarRef(op->getTrueExpr()) 722239462Sdim || isBlockVarRef(op->getFalseExpr()); 723239462Sdim 724239462Sdim // OVEs are required to support BinaryConditionalOperators. 725239462Sdim } else if (const OpaqueValueExpr *op 726239462Sdim = dyn_cast<OpaqueValueExpr>(E)) { 727239462Sdim if (const Expr *src = op->getSourceExpr()) 728239462Sdim return isBlockVarRef(src); 729239462Sdim 730239462Sdim // Casts are necessary to get things like (*(int*)&var) = foo(). 731239462Sdim // We don't really care about the kind of cast here, except 732239462Sdim // we don't want to look through l2r casts, because it's okay 733239462Sdim // to get the *value* in a __block variable. 734239462Sdim } else if (const CastExpr *cast = dyn_cast<CastExpr>(E)) { 735239462Sdim if (cast->getCastKind() == CK_LValueToRValue) 736239462Sdim return false; 737239462Sdim return isBlockVarRef(cast->getSubExpr()); 738239462Sdim 739239462Sdim // Handle unary operators. Again, just aggressively look through 740239462Sdim // it, ignoring the operation. 741239462Sdim } else if (const UnaryOperator *uop = dyn_cast<UnaryOperator>(E)) { 742239462Sdim return isBlockVarRef(uop->getSubExpr()); 743239462Sdim 744239462Sdim // Look into the base of a field access. 745239462Sdim } else if (const MemberExpr *mem = dyn_cast<MemberExpr>(E)) { 746239462Sdim return isBlockVarRef(mem->getBase()); 747239462Sdim 748239462Sdim // Look into the base of a subscript. 749239462Sdim } else if (const ArraySubscriptExpr *sub = dyn_cast<ArraySubscriptExpr>(E)) { 750239462Sdim return isBlockVarRef(sub->getBase()); 751239462Sdim } 752239462Sdim 753239462Sdim return false; 754239462Sdim} 755239462Sdim 756193326Sedvoid AggExprEmitter::VisitBinAssign(const BinaryOperator *E) { 757193326Sed // For an assignment to work, the value on the right has 758193326Sed // to be compatible with the value on the left. 759193326Sed assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(), 760193326Sed E->getRHS()->getType()) 761193326Sed && "Invalid assignment"); 762218893Sdim 763239462Sdim // If the LHS might be a __block variable, and the RHS can 764239462Sdim // potentially cause a block copy, we need to evaluate the RHS first 765239462Sdim // so that the assignment goes the right place. 766239462Sdim // This is pretty semantically fragile. 767239462Sdim if (isBlockVarRef(E->getLHS()) && 768239462Sdim E->getRHS()->HasSideEffects(CGF.getContext())) { 769239462Sdim // Ensure that we have a destination, and evaluate the RHS into that. 770239462Sdim EnsureDest(E->getRHS()->getType()); 771239462Sdim Visit(E->getRHS()); 772239462Sdim 773239462Sdim // Now emit the LHS and copy into it. 774239462Sdim LValue LHS = CGF.EmitLValue(E->getLHS()); 775239462Sdim 776239462Sdim EmitCopy(E->getLHS()->getType(), 777239462Sdim AggValueSlot::forLValue(LHS, AggValueSlot::IsDestructed, 778239462Sdim needsGC(E->getLHS()->getType()), 779239462Sdim AggValueSlot::IsAliased), 780239462Sdim Dest); 781239462Sdim return; 782239462Sdim } 783221345Sdim 784193326Sed LValue LHS = CGF.EmitLValue(E->getLHS()); 785193326Sed 786234353Sdim // Codegen the RHS so that it stores directly into the LHS. 787234353Sdim AggValueSlot LHSSlot = 788234353Sdim AggValueSlot::forLValue(LHS, AggValueSlot::IsDestructed, 789234353Sdim needsGC(E->getLHS()->getType()), 790234353Sdim AggValueSlot::IsAliased); 791239462Sdim CGF.EmitAggExpr(E->getRHS(), LHSSlot); 792239462Sdim 793239462Sdim // Copy into the destination if the assignment isn't ignored. 794239462Sdim EmitFinalDestCopy(E->getType(), LHS); 795193326Sed} 796193326Sed 797218893Sdimvoid AggExprEmitter:: 798218893SdimVisitAbstractConditionalOperator(const AbstractConditionalOperator *E) { 799193326Sed llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 800193326Sed llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 801193326Sed llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 802198092Srdivacky 803218893Sdim // Bind the common expression if necessary. 804218893Sdim CodeGenFunction::OpaqueValueMapping binding(CGF, E); 805218893Sdim 806218893Sdim CodeGenFunction::ConditionalEvaluation eval(CGF); 807201361Srdivacky CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); 808198092Srdivacky 809218893Sdim // Save whether the destination's lifetime is externally managed. 810226633Sdim bool isExternallyDestructed = Dest.isExternallyDestructed(); 811218893Sdim 812218893Sdim eval.begin(CGF); 813193326Sed CGF.EmitBlock(LHSBlock); 814218893Sdim Visit(E->getTrueExpr()); 815218893Sdim eval.end(CGF); 816198092Srdivacky 817218893Sdim assert(CGF.HaveInsertPoint() && "expression evaluation ended with no IP!"); 818218893Sdim CGF.Builder.CreateBr(ContBlock); 819193326Sed 820218893Sdim // If the result of an agg expression is unused, then the emission 821218893Sdim // of the LHS might need to create a destination slot. That's fine 822218893Sdim // with us, and we can safely emit the RHS into the same slot, but 823226633Sdim // we shouldn't claim that it's already being destructed. 824226633Sdim Dest.setExternallyDestructed(isExternallyDestructed); 825198092Srdivacky 826218893Sdim eval.begin(CGF); 827193326Sed CGF.EmitBlock(RHSBlock); 828218893Sdim Visit(E->getFalseExpr()); 829218893Sdim eval.end(CGF); 830198092Srdivacky 831193326Sed CGF.EmitBlock(ContBlock); 832193326Sed} 833193326Sed 834198092Srdivackyvoid AggExprEmitter::VisitChooseExpr(const ChooseExpr *CE) { 835198092Srdivacky Visit(CE->getChosenSubExpr(CGF.getContext())); 836198092Srdivacky} 837198092Srdivacky 838193326Sedvoid AggExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 839193326Sed llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 840193326Sed llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 841193326Sed 842193326Sed if (!ArgPtr) { 843193326Sed CGF.ErrorUnsupported(VE, "aggregate va_arg expression"); 844193326Sed return; 845193326Sed } 846193326Sed 847239462Sdim EmitFinalDestCopy(VE->getType(), CGF.MakeAddrLValue(ArgPtr, VE->getType())); 848193326Sed} 849193326Sed 850193326Sedvoid AggExprEmitter::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) { 851218893Sdim // Ensure that we have a slot, but if we already do, remember 852226633Sdim // whether it was externally destructed. 853226633Sdim bool wasExternallyDestructed = Dest.isExternallyDestructed(); 854239462Sdim EnsureDest(E->getType()); 855198092Srdivacky 856226633Sdim // We're going to push a destructor if there isn't already one. 857226633Sdim Dest.setExternallyDestructed(); 858226633Sdim 859218893Sdim Visit(E->getSubExpr()); 860193326Sed 861226633Sdim // Push that destructor we promised. 862226633Sdim if (!wasExternallyDestructed) 863234353Sdim CGF.EmitCXXTemporary(E->getTemporary(), E->getType(), Dest.getAddr()); 864193326Sed} 865193326Sed 866193326Sedvoid 867193326SedAggExprEmitter::VisitCXXConstructExpr(const CXXConstructExpr *E) { 868218893Sdim AggValueSlot Slot = EnsureSlot(E->getType()); 869218893Sdim CGF.EmitCXXConstructExpr(E, Slot); 870193326Sed} 871193326Sed 872234353Sdimvoid 873234353SdimAggExprEmitter::VisitLambdaExpr(LambdaExpr *E) { 874234353Sdim AggValueSlot Slot = EnsureSlot(E->getType()); 875234353Sdim CGF.EmitLambdaExpr(E, Slot); 876234353Sdim} 877234353Sdim 878218893Sdimvoid AggExprEmitter::VisitExprWithCleanups(ExprWithCleanups *E) { 879234353Sdim CGF.enterFullExpression(E); 880234353Sdim CodeGenFunction::RunCleanupsScope cleanups(CGF); 881234353Sdim Visit(E->getSubExpr()); 882193326Sed} 883193326Sed 884210299Sedvoid AggExprEmitter::VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) { 885218893Sdim QualType T = E->getType(); 886218893Sdim AggValueSlot Slot = EnsureSlot(T); 887224145Sdim EmitNullInitializationToLValue(CGF.MakeAddrLValue(Slot.getAddr(), T)); 888198398Srdivacky} 889198398Srdivacky 890201361Srdivackyvoid AggExprEmitter::VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) { 891218893Sdim QualType T = E->getType(); 892218893Sdim AggValueSlot Slot = EnsureSlot(T); 893224145Sdim EmitNullInitializationToLValue(CGF.MakeAddrLValue(Slot.getAddr(), T)); 894218893Sdim} 895201361Srdivacky 896218893Sdim/// isSimpleZero - If emitting this value will obviously just cause a store of 897218893Sdim/// zero to memory, return true. This can return false if uncertain, so it just 898218893Sdim/// handles simple cases. 899218893Sdimstatic bool isSimpleZero(const Expr *E, CodeGenFunction &CGF) { 900221345Sdim E = E->IgnoreParens(); 901221345Sdim 902218893Sdim // 0 903218893Sdim if (const IntegerLiteral *IL = dyn_cast<IntegerLiteral>(E)) 904218893Sdim return IL->getValue() == 0; 905218893Sdim // +0.0 906218893Sdim if (const FloatingLiteral *FL = dyn_cast<FloatingLiteral>(E)) 907218893Sdim return FL->getValue().isPosZero(); 908218893Sdim // int() 909218893Sdim if ((isa<ImplicitValueInitExpr>(E) || isa<CXXScalarValueInitExpr>(E)) && 910218893Sdim CGF.getTypes().isZeroInitializable(E->getType())) 911218893Sdim return true; 912218893Sdim // (int*)0 - Null pointer expressions. 913218893Sdim if (const CastExpr *ICE = dyn_cast<CastExpr>(E)) 914218893Sdim return ICE->getCastKind() == CK_NullToPointer; 915218893Sdim // '\0' 916218893Sdim if (const CharacterLiteral *CL = dyn_cast<CharacterLiteral>(E)) 917218893Sdim return CL->getValue() == 0; 918218893Sdim 919218893Sdim // Otherwise, hard case: conservatively return false. 920218893Sdim return false; 921201361Srdivacky} 922201361Srdivacky 923218893Sdim 924203955Srdivackyvoid 925224145SdimAggExprEmitter::EmitInitializationToLValue(Expr* E, LValue LV) { 926224145Sdim QualType type = LV.getType(); 927193326Sed // FIXME: Ignore result? 928193326Sed // FIXME: Are initializers affected by volatile? 929218893Sdim if (Dest.isZeroed() && isSimpleZero(E, CGF)) { 930218893Sdim // Storing "i32 0" to a zero'd memory location is a noop. 931218893Sdim } else if (isa<ImplicitValueInitExpr>(E)) { 932224145Sdim EmitNullInitializationToLValue(LV); 933224145Sdim } else if (type->isReferenceType()) { 934210299Sed RValue RV = CGF.EmitReferenceBindingToExpr(E, /*InitializedDecl=*/0); 935224145Sdim CGF.EmitStoreThroughLValue(RV, LV); 936224145Sdim } else if (type->isAnyComplexType()) { 937193326Sed CGF.EmitComplexExprIntoAddr(E, LV.getAddress(), false); 938224145Sdim } else if (CGF.hasAggregateLLVMType(type)) { 939226633Sdim CGF.EmitAggExpr(E, AggValueSlot::forLValue(LV, 940226633Sdim AggValueSlot::IsDestructed, 941226633Sdim AggValueSlot::DoesNotNeedGCBarriers, 942226633Sdim AggValueSlot::IsNotAliased, 943224145Sdim Dest.isZeroed())); 944224145Sdim } else if (LV.isSimple()) { 945224145Sdim CGF.EmitScalarInit(E, /*D=*/0, LV, /*Captured=*/false); 946193326Sed } else { 947224145Sdim CGF.EmitStoreThroughLValue(RValue::get(CGF.EmitScalarExpr(E)), LV); 948193326Sed } 949193326Sed} 950193326Sed 951224145Sdimvoid AggExprEmitter::EmitNullInitializationToLValue(LValue lv) { 952224145Sdim QualType type = lv.getType(); 953224145Sdim 954218893Sdim // If the destination slot is already zeroed out before the aggregate is 955218893Sdim // copied into it, we don't have to emit any zeros here. 956224145Sdim if (Dest.isZeroed() && CGF.getTypes().isZeroInitializable(type)) 957218893Sdim return; 958218893Sdim 959224145Sdim if (!CGF.hasAggregateLLVMType(type)) { 960234353Sdim // For non-aggregates, we can store zero. 961224145Sdim llvm::Value *null = llvm::Constant::getNullValue(CGF.ConvertType(type)); 962234353Sdim // Note that the following is not equivalent to 963234353Sdim // EmitStoreThroughBitfieldLValue for ARC types. 964234353Sdim if (lv.isBitField()) { 965234353Sdim CGF.EmitStoreThroughBitfieldLValue(RValue::get(null), lv); 966234353Sdim } else { 967234353Sdim assert(lv.isSimple()); 968234353Sdim CGF.EmitStoreOfScalar(null, lv, /* isInitialization */ true); 969234353Sdim } 970193326Sed } else { 971193326Sed // There's a potential optimization opportunity in combining 972193326Sed // memsets; that would be easy for arrays, but relatively 973193326Sed // difficult for structures with the current code. 974224145Sdim CGF.EmitNullInitialization(lv.getAddress(), lv.getType()); 975193326Sed } 976193326Sed} 977193326Sed 978193326Sedvoid AggExprEmitter::VisitInitListExpr(InitListExpr *E) { 979193326Sed#if 0 980200583Srdivacky // FIXME: Assess perf here? Figure out what cases are worth optimizing here 981200583Srdivacky // (Length of globals? Chunks of zeroed-out space?). 982193326Sed // 983193326Sed // If we can, prefer a copy from a global; this is a lot less code for long 984193326Sed // globals, and it's easier for the current optimizers to analyze. 985200583Srdivacky if (llvm::Constant* C = CGF.CGM.EmitConstantExpr(E, E->getType(), &CGF)) { 986193326Sed llvm::GlobalVariable* GV = 987200583Srdivacky new llvm::GlobalVariable(CGF.CGM.getModule(), C->getType(), true, 988200583Srdivacky llvm::GlobalValue::InternalLinkage, C, ""); 989239462Sdim EmitFinalDestCopy(E->getType(), CGF.MakeAddrLValue(GV, E->getType())); 990193326Sed return; 991193326Sed } 992193326Sed#endif 993218893Sdim if (E->hadArrayRangeDesignator()) 994193326Sed CGF.ErrorUnsupported(E, "GNU array range designator extension"); 995193326Sed 996234353Sdim if (E->initializesStdInitializerList()) { 997234353Sdim EmitStdInitializerList(Dest.getAddr(), E); 998234353Sdim return; 999234353Sdim } 1000218893Sdim 1001234982Sdim AggValueSlot Dest = EnsureSlot(E->getType()); 1002234982Sdim LValue DestLV = CGF.MakeAddrLValue(Dest.getAddr(), E->getType(), 1003234982Sdim Dest.getAlignment()); 1004234353Sdim 1005193326Sed // Handle initialization of an array. 1006193326Sed if (E->getType()->isArrayType()) { 1007234982Sdim if (E->isStringLiteralInit()) 1008234982Sdim return Visit(E->getInit(0)); 1009193326Sed 1010234353Sdim QualType elementType = 1011234353Sdim CGF.getContext().getAsArrayType(E->getType())->getElementType(); 1012193326Sed 1013234353Sdim llvm::PointerType *APType = 1014234982Sdim cast<llvm::PointerType>(Dest.getAddr()->getType()); 1015234353Sdim llvm::ArrayType *AType = 1016234353Sdim cast<llvm::ArrayType>(APType->getElementType()); 1017224145Sdim 1018234982Sdim EmitArrayInit(Dest.getAddr(), AType, elementType, E); 1019193326Sed return; 1020193326Sed } 1021198092Srdivacky 1022193326Sed assert(E->getType()->isRecordType() && "Only support structs/unions here!"); 1023198092Srdivacky 1024193326Sed // Do struct initialization; this code just sets each individual member 1025193326Sed // to the approprate value. This makes bitfield support automatic; 1026193326Sed // the disadvantage is that the generated code is more difficult for 1027193326Sed // the optimizer, especially with bitfields. 1028193326Sed unsigned NumInitElements = E->getNumInits(); 1029224145Sdim RecordDecl *record = E->getType()->castAs<RecordType>()->getDecl(); 1030212904Sdim 1031224145Sdim if (record->isUnion()) { 1032193326Sed // Only initialize one field of a union. The field itself is 1033193326Sed // specified by the initializer list. 1034193326Sed if (!E->getInitializedFieldInUnion()) { 1035193326Sed // Empty union; we have nothing to do. 1036198092Srdivacky 1037193326Sed#ifndef NDEBUG 1038193326Sed // Make sure that it's really an empty and not a failure of 1039193326Sed // semantic analysis. 1040224145Sdim for (RecordDecl::field_iterator Field = record->field_begin(), 1041224145Sdim FieldEnd = record->field_end(); 1042193326Sed Field != FieldEnd; ++Field) 1043193326Sed assert(Field->isUnnamedBitfield() && "Only unnamed bitfields allowed"); 1044193326Sed#endif 1045193326Sed return; 1046193326Sed } 1047193326Sed 1048193326Sed // FIXME: volatility 1049193326Sed FieldDecl *Field = E->getInitializedFieldInUnion(); 1050218893Sdim 1051234982Sdim LValue FieldLoc = CGF.EmitLValueForFieldInitialization(DestLV, Field); 1052193326Sed if (NumInitElements) { 1053193326Sed // Store the initializer into the field 1054224145Sdim EmitInitializationToLValue(E->getInit(0), FieldLoc); 1055193326Sed } else { 1056218893Sdim // Default-initialize to null. 1057224145Sdim EmitNullInitializationToLValue(FieldLoc); 1058193326Sed } 1059193326Sed 1060193326Sed return; 1061193326Sed } 1062198092Srdivacky 1063224145Sdim // We'll need to enter cleanup scopes in case any of the member 1064224145Sdim // initializers throw an exception. 1065226633Sdim SmallVector<EHScopeStack::stable_iterator, 16> cleanups; 1066234353Sdim llvm::Instruction *cleanupDominator = 0; 1067224145Sdim 1068193326Sed // Here we iterate over the fields; this makes it simpler to both 1069193326Sed // default-initialize fields and skip over unnamed fields. 1070224145Sdim unsigned curInitIndex = 0; 1071224145Sdim for (RecordDecl::field_iterator field = record->field_begin(), 1072224145Sdim fieldEnd = record->field_end(); 1073224145Sdim field != fieldEnd; ++field) { 1074224145Sdim // We're done once we hit the flexible array member. 1075224145Sdim if (field->getType()->isIncompleteArrayType()) 1076193326Sed break; 1077193326Sed 1078224145Sdim // Always skip anonymous bitfields. 1079224145Sdim if (field->isUnnamedBitfield()) 1080193326Sed continue; 1081193326Sed 1082224145Sdim // We're done if we reach the end of the explicit initializers, we 1083224145Sdim // have a zeroed object, and the rest of the fields are 1084224145Sdim // zero-initializable. 1085224145Sdim if (curInitIndex == NumInitElements && Dest.isZeroed() && 1086218893Sdim CGF.getTypes().isZeroInitializable(E->getType())) 1087218893Sdim break; 1088218893Sdim 1089234982Sdim 1090234982Sdim LValue LV = CGF.EmitLValueForFieldInitialization(DestLV, *field); 1091193326Sed // We never generate write-barries for initialized fields. 1092224145Sdim LV.setNonGC(true); 1093218893Sdim 1094224145Sdim if (curInitIndex < NumInitElements) { 1095204962Srdivacky // Store the initializer into the field. 1096224145Sdim EmitInitializationToLValue(E->getInit(curInitIndex++), LV); 1097193326Sed } else { 1098193326Sed // We're out of initalizers; default-initialize to null 1099224145Sdim EmitNullInitializationToLValue(LV); 1100193326Sed } 1101224145Sdim 1102224145Sdim // Push a destructor if necessary. 1103224145Sdim // FIXME: if we have an array of structures, all explicitly 1104224145Sdim // initialized, we can end up pushing a linear number of cleanups. 1105224145Sdim bool pushedCleanup = false; 1106224145Sdim if (QualType::DestructionKind dtorKind 1107224145Sdim = field->getType().isDestructedType()) { 1108224145Sdim assert(LV.isSimple()); 1109224145Sdim if (CGF.needsEHCleanup(dtorKind)) { 1110234353Sdim if (!cleanupDominator) 1111234353Sdim cleanupDominator = CGF.Builder.CreateUnreachable(); // placeholder 1112234353Sdim 1113224145Sdim CGF.pushDestroy(EHCleanup, LV.getAddress(), field->getType(), 1114224145Sdim CGF.getDestroyer(dtorKind), false); 1115224145Sdim cleanups.push_back(CGF.EHStack.stable_begin()); 1116224145Sdim pushedCleanup = true; 1117224145Sdim } 1118224145Sdim } 1119218893Sdim 1120218893Sdim // If the GEP didn't get used because of a dead zero init or something 1121218893Sdim // else, clean it up for -O0 builds and general tidiness. 1122224145Sdim if (!pushedCleanup && LV.isSimple()) 1123218893Sdim if (llvm::GetElementPtrInst *GEP = 1124224145Sdim dyn_cast<llvm::GetElementPtrInst>(LV.getAddress())) 1125218893Sdim if (GEP->use_empty()) 1126218893Sdim GEP->eraseFromParent(); 1127193326Sed } 1128224145Sdim 1129224145Sdim // Deactivate all the partial cleanups in reverse order, which 1130224145Sdim // generally means popping them. 1131224145Sdim for (unsigned i = cleanups.size(); i != 0; --i) 1132234353Sdim CGF.DeactivateCleanupBlock(cleanups[i-1], cleanupDominator); 1133234353Sdim 1134234353Sdim // Destroy the placeholder if we made one. 1135234353Sdim if (cleanupDominator) 1136234353Sdim cleanupDominator->eraseFromParent(); 1137193326Sed} 1138193326Sed 1139193326Sed//===----------------------------------------------------------------------===// 1140193326Sed// Entry Points into this File 1141193326Sed//===----------------------------------------------------------------------===// 1142193326Sed 1143218893Sdim/// GetNumNonZeroBytesInInit - Get an approximate count of the number of 1144218893Sdim/// non-zero bytes that will be stored when outputting the initializer for the 1145218893Sdim/// specified initializer expression. 1146221345Sdimstatic CharUnits GetNumNonZeroBytesInInit(const Expr *E, CodeGenFunction &CGF) { 1147221345Sdim E = E->IgnoreParens(); 1148218893Sdim 1149218893Sdim // 0 and 0.0 won't require any non-zero stores! 1150221345Sdim if (isSimpleZero(E, CGF)) return CharUnits::Zero(); 1151218893Sdim 1152218893Sdim // If this is an initlist expr, sum up the size of sizes of the (present) 1153218893Sdim // elements. If this is something weird, assume the whole thing is non-zero. 1154218893Sdim const InitListExpr *ILE = dyn_cast<InitListExpr>(E); 1155218893Sdim if (ILE == 0 || !CGF.getTypes().isZeroInitializable(ILE->getType())) 1156221345Sdim return CGF.getContext().getTypeSizeInChars(E->getType()); 1157218893Sdim 1158218893Sdim // InitListExprs for structs have to be handled carefully. If there are 1159218893Sdim // reference members, we need to consider the size of the reference, not the 1160218893Sdim // referencee. InitListExprs for unions and arrays can't have references. 1161218893Sdim if (const RecordType *RT = E->getType()->getAs<RecordType>()) { 1162218893Sdim if (!RT->isUnionType()) { 1163218893Sdim RecordDecl *SD = E->getType()->getAs<RecordType>()->getDecl(); 1164221345Sdim CharUnits NumNonZeroBytes = CharUnits::Zero(); 1165218893Sdim 1166218893Sdim unsigned ILEElement = 0; 1167218893Sdim for (RecordDecl::field_iterator Field = SD->field_begin(), 1168218893Sdim FieldEnd = SD->field_end(); Field != FieldEnd; ++Field) { 1169218893Sdim // We're done once we hit the flexible array member or run out of 1170218893Sdim // InitListExpr elements. 1171218893Sdim if (Field->getType()->isIncompleteArrayType() || 1172218893Sdim ILEElement == ILE->getNumInits()) 1173218893Sdim break; 1174218893Sdim if (Field->isUnnamedBitfield()) 1175218893Sdim continue; 1176218893Sdim 1177218893Sdim const Expr *E = ILE->getInit(ILEElement++); 1178218893Sdim 1179218893Sdim // Reference values are always non-null and have the width of a pointer. 1180218893Sdim if (Field->getType()->isReferenceType()) 1181221345Sdim NumNonZeroBytes += CGF.getContext().toCharUnitsFromBits( 1182226633Sdim CGF.getContext().getTargetInfo().getPointerWidth(0)); 1183218893Sdim else 1184218893Sdim NumNonZeroBytes += GetNumNonZeroBytesInInit(E, CGF); 1185218893Sdim } 1186218893Sdim 1187218893Sdim return NumNonZeroBytes; 1188218893Sdim } 1189218893Sdim } 1190218893Sdim 1191218893Sdim 1192221345Sdim CharUnits NumNonZeroBytes = CharUnits::Zero(); 1193218893Sdim for (unsigned i = 0, e = ILE->getNumInits(); i != e; ++i) 1194218893Sdim NumNonZeroBytes += GetNumNonZeroBytesInInit(ILE->getInit(i), CGF); 1195218893Sdim return NumNonZeroBytes; 1196218893Sdim} 1197218893Sdim 1198218893Sdim/// CheckAggExprForMemSetUse - If the initializer is large and has a lot of 1199218893Sdim/// zeros in it, emit a memset and avoid storing the individual zeros. 1200218893Sdim/// 1201218893Sdimstatic void CheckAggExprForMemSetUse(AggValueSlot &Slot, const Expr *E, 1202218893Sdim CodeGenFunction &CGF) { 1203218893Sdim // If the slot is already known to be zeroed, nothing to do. Don't mess with 1204218893Sdim // volatile stores. 1205218893Sdim if (Slot.isZeroed() || Slot.isVolatile() || Slot.getAddr() == 0) return; 1206221345Sdim 1207221345Sdim // C++ objects with a user-declared constructor don't need zero'ing. 1208234353Sdim if (CGF.getContext().getLangOpts().CPlusPlus) 1209221345Sdim if (const RecordType *RT = CGF.getContext() 1210221345Sdim .getBaseElementType(E->getType())->getAs<RecordType>()) { 1211221345Sdim const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl()); 1212221345Sdim if (RD->hasUserDeclaredConstructor()) 1213221345Sdim return; 1214221345Sdim } 1215221345Sdim 1216218893Sdim // If the type is 16-bytes or smaller, prefer individual stores over memset. 1217221345Sdim std::pair<CharUnits, CharUnits> TypeInfo = 1218221345Sdim CGF.getContext().getTypeInfoInChars(E->getType()); 1219221345Sdim if (TypeInfo.first <= CharUnits::fromQuantity(16)) 1220218893Sdim return; 1221218893Sdim 1222218893Sdim // Check to see if over 3/4 of the initializer are known to be zero. If so, 1223218893Sdim // we prefer to emit memset + individual stores for the rest. 1224221345Sdim CharUnits NumNonZeroBytes = GetNumNonZeroBytesInInit(E, CGF); 1225221345Sdim if (NumNonZeroBytes*4 > TypeInfo.first) 1226218893Sdim return; 1227218893Sdim 1228218893Sdim // Okay, it seems like a good idea to use an initial memset, emit the call. 1229221345Sdim llvm::Constant *SizeVal = CGF.Builder.getInt64(TypeInfo.first.getQuantity()); 1230221345Sdim CharUnits Align = TypeInfo.second; 1231218893Sdim 1232218893Sdim llvm::Value *Loc = Slot.getAddr(); 1233218893Sdim 1234234353Sdim Loc = CGF.Builder.CreateBitCast(Loc, CGF.Int8PtrTy); 1235221345Sdim CGF.Builder.CreateMemSet(Loc, CGF.Builder.getInt8(0), SizeVal, 1236221345Sdim Align.getQuantity(), false); 1237218893Sdim 1238218893Sdim // Tell the AggExprEmitter that the slot is known zero. 1239218893Sdim Slot.setZeroed(); 1240218893Sdim} 1241218893Sdim 1242218893Sdim 1243218893Sdim 1244218893Sdim 1245193326Sed/// EmitAggExpr - Emit the computation of the specified expression of aggregate 1246193326Sed/// type. The result is computed into DestPtr. Note that if DestPtr is null, 1247193326Sed/// the value of the aggregate expression is not needed. If VolatileDest is 1248193326Sed/// true, DestPtr cannot be 0. 1249239462Sdimvoid CodeGenFunction::EmitAggExpr(const Expr *E, AggValueSlot Slot) { 1250193326Sed assert(E && hasAggregateLLVMType(E->getType()) && 1251193326Sed "Invalid aggregate expression to emit"); 1252218893Sdim assert((Slot.getAddr() != 0 || Slot.isIgnored()) && 1253218893Sdim "slot has bits but no address"); 1254198092Srdivacky 1255218893Sdim // Optimize the slot if possible. 1256218893Sdim CheckAggExprForMemSetUse(Slot, E, *this); 1257218893Sdim 1258239462Sdim AggExprEmitter(*this, Slot).Visit(const_cast<Expr*>(E)); 1259193326Sed} 1260193326Sed 1261203955SrdivackyLValue CodeGenFunction::EmitAggExprToLValue(const Expr *E) { 1262203955Srdivacky assert(hasAggregateLLVMType(E->getType()) && "Invalid argument!"); 1263203955Srdivacky llvm::Value *Temp = CreateMemTemp(E->getType()); 1264212904Sdim LValue LV = MakeAddrLValue(Temp, E->getType()); 1265226633Sdim EmitAggExpr(E, AggValueSlot::forLValue(LV, AggValueSlot::IsNotDestructed, 1266226633Sdim AggValueSlot::DoesNotNeedGCBarriers, 1267226633Sdim AggValueSlot::IsNotAliased)); 1268212904Sdim return LV; 1269203955Srdivacky} 1270203955Srdivacky 1271193326Sedvoid CodeGenFunction::EmitAggregateCopy(llvm::Value *DestPtr, 1272193326Sed llvm::Value *SrcPtr, QualType Ty, 1273239462Sdim bool isVolatile, 1274239462Sdim CharUnits alignment) { 1275193326Sed assert(!Ty->isAnyComplexType() && "Shouldn't happen for complex"); 1276198092Srdivacky 1277234353Sdim if (getContext().getLangOpts().CPlusPlus) { 1278207619Srdivacky if (const RecordType *RT = Ty->getAs<RecordType>()) { 1279208600Srdivacky CXXRecordDecl *Record = cast<CXXRecordDecl>(RT->getDecl()); 1280208600Srdivacky assert((Record->hasTrivialCopyConstructor() || 1281226633Sdim Record->hasTrivialCopyAssignment() || 1282226633Sdim Record->hasTrivialMoveConstructor() || 1283226633Sdim Record->hasTrivialMoveAssignment()) && 1284208600Srdivacky "Trying to aggregate-copy a type without a trivial copy " 1285208600Srdivacky "constructor or assignment operator"); 1286208600Srdivacky // Ignore empty classes in C++. 1287208600Srdivacky if (Record->isEmpty()) 1288207619Srdivacky return; 1289207619Srdivacky } 1290207619Srdivacky } 1291207619Srdivacky 1292193326Sed // Aggregate assignment turns into llvm.memcpy. This is almost valid per 1293193326Sed // C99 6.5.16.1p3, which states "If the value being stored in an object is 1294193326Sed // read from another object that overlaps in anyway the storage of the first 1295193326Sed // object, then the overlap shall be exact and the two objects shall have 1296193326Sed // qualified or unqualified versions of a compatible type." 1297193326Sed // 1298193326Sed // memcpy is not defined if the source and destination pointers are exactly 1299193326Sed // equal, but other compilers do this optimization, and almost every memcpy 1300193326Sed // implementation handles this case safely. If there is a libc that does not 1301193326Sed // safely handle this, we can add a target hook. 1302198092Srdivacky 1303193326Sed // Get size and alignment info for this aggregate. 1304221345Sdim std::pair<CharUnits, CharUnits> TypeInfo = 1305221345Sdim getContext().getTypeInfoInChars(Ty); 1306198092Srdivacky 1307239462Sdim if (alignment.isZero()) 1308239462Sdim alignment = TypeInfo.second; 1309234353Sdim 1310193326Sed // FIXME: Handle variable sized types. 1311198092Srdivacky 1312193326Sed // FIXME: If we have a volatile struct, the optimizer can remove what might 1313193326Sed // appear to be `extra' memory ops: 1314193326Sed // 1315193326Sed // volatile struct { int i; } a, b; 1316193326Sed // 1317193326Sed // int main() { 1318193326Sed // a = b; 1319193326Sed // a = b; 1320193326Sed // } 1321193326Sed // 1322206275Srdivacky // we need to use a different call here. We use isVolatile to indicate when 1323193326Sed // either the source or the destination is volatile. 1324206275Srdivacky 1325226633Sdim llvm::PointerType *DPT = cast<llvm::PointerType>(DestPtr->getType()); 1326226633Sdim llvm::Type *DBP = 1327218893Sdim llvm::Type::getInt8PtrTy(getLLVMContext(), DPT->getAddressSpace()); 1328226633Sdim DestPtr = Builder.CreateBitCast(DestPtr, DBP); 1329206275Srdivacky 1330226633Sdim llvm::PointerType *SPT = cast<llvm::PointerType>(SrcPtr->getType()); 1331226633Sdim llvm::Type *SBP = 1332218893Sdim llvm::Type::getInt8PtrTy(getLLVMContext(), SPT->getAddressSpace()); 1333226633Sdim SrcPtr = Builder.CreateBitCast(SrcPtr, SBP); 1334206275Srdivacky 1335224145Sdim // Don't do any of the memmove_collectable tests if GC isn't set. 1336234353Sdim if (CGM.getLangOpts().getGC() == LangOptions::NonGC) { 1337224145Sdim // fall through 1338224145Sdim } else if (const RecordType *RecordTy = Ty->getAs<RecordType>()) { 1339210299Sed RecordDecl *Record = RecordTy->getDecl(); 1340210299Sed if (Record->hasObjectMember()) { 1341221345Sdim CharUnits size = TypeInfo.first; 1342226633Sdim llvm::Type *SizeTy = ConvertType(getContext().getSizeType()); 1343221345Sdim llvm::Value *SizeVal = llvm::ConstantInt::get(SizeTy, size.getQuantity()); 1344210299Sed CGM.getObjCRuntime().EmitGCMemmoveCollectable(*this, DestPtr, SrcPtr, 1345210299Sed SizeVal); 1346210299Sed return; 1347210299Sed } 1348224145Sdim } else if (Ty->isArrayType()) { 1349210299Sed QualType BaseType = getContext().getBaseElementType(Ty); 1350210299Sed if (const RecordType *RecordTy = BaseType->getAs<RecordType>()) { 1351210299Sed if (RecordTy->getDecl()->hasObjectMember()) { 1352221345Sdim CharUnits size = TypeInfo.first; 1353226633Sdim llvm::Type *SizeTy = ConvertType(getContext().getSizeType()); 1354221345Sdim llvm::Value *SizeVal = 1355221345Sdim llvm::ConstantInt::get(SizeTy, size.getQuantity()); 1356210299Sed CGM.getObjCRuntime().EmitGCMemmoveCollectable(*this, DestPtr, SrcPtr, 1357210299Sed SizeVal); 1358210299Sed return; 1359210299Sed } 1360210299Sed } 1361210299Sed } 1362210299Sed 1363218893Sdim Builder.CreateMemCpy(DestPtr, SrcPtr, 1364221345Sdim llvm::ConstantInt::get(IntPtrTy, 1365221345Sdim TypeInfo.first.getQuantity()), 1366239462Sdim alignment.getQuantity(), isVolatile); 1367193326Sed} 1368234353Sdim 1369234353Sdimvoid CodeGenFunction::MaybeEmitStdInitializerListCleanup(llvm::Value *loc, 1370234353Sdim const Expr *init) { 1371234353Sdim const ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(init); 1372234353Sdim if (cleanups) 1373234353Sdim init = cleanups->getSubExpr(); 1374234353Sdim 1375234353Sdim if (isa<InitListExpr>(init) && 1376234353Sdim cast<InitListExpr>(init)->initializesStdInitializerList()) { 1377234353Sdim // We initialized this std::initializer_list with an initializer list. 1378234353Sdim // A backing array was created. Push a cleanup for it. 1379234353Sdim EmitStdInitializerListCleanup(loc, cast<InitListExpr>(init)); 1380234353Sdim } 1381234353Sdim} 1382234353Sdim 1383234353Sdimstatic void EmitRecursiveStdInitializerListCleanup(CodeGenFunction &CGF, 1384234353Sdim llvm::Value *arrayStart, 1385234353Sdim const InitListExpr *init) { 1386234353Sdim // Check if there are any recursive cleanups to do, i.e. if we have 1387234353Sdim // std::initializer_list<std::initializer_list<obj>> list = {{obj()}}; 1388234353Sdim // then we need to destroy the inner array as well. 1389234353Sdim for (unsigned i = 0, e = init->getNumInits(); i != e; ++i) { 1390234353Sdim const InitListExpr *subInit = dyn_cast<InitListExpr>(init->getInit(i)); 1391234353Sdim if (!subInit || !subInit->initializesStdInitializerList()) 1392234353Sdim continue; 1393234353Sdim 1394234353Sdim // This one needs to be destroyed. Get the address of the std::init_list. 1395234353Sdim llvm::Value *offset = llvm::ConstantInt::get(CGF.SizeTy, i); 1396234353Sdim llvm::Value *loc = CGF.Builder.CreateInBoundsGEP(arrayStart, offset, 1397234353Sdim "std.initlist"); 1398234353Sdim CGF.EmitStdInitializerListCleanup(loc, subInit); 1399234353Sdim } 1400234353Sdim} 1401234353Sdim 1402234353Sdimvoid CodeGenFunction::EmitStdInitializerListCleanup(llvm::Value *loc, 1403234353Sdim const InitListExpr *init) { 1404234353Sdim ASTContext &ctx = getContext(); 1405234353Sdim QualType element = GetStdInitializerListElementType(init->getType()); 1406234353Sdim unsigned numInits = init->getNumInits(); 1407234353Sdim llvm::APInt size(ctx.getTypeSize(ctx.getSizeType()), numInits); 1408234353Sdim QualType array =ctx.getConstantArrayType(element, size, ArrayType::Normal, 0); 1409234353Sdim QualType arrayPtr = ctx.getPointerType(array); 1410234353Sdim llvm::Type *arrayPtrType = ConvertType(arrayPtr); 1411234353Sdim 1412234353Sdim // lvalue is the location of a std::initializer_list, which as its first 1413234353Sdim // element has a pointer to the array we want to destroy. 1414234353Sdim llvm::Value *startPointer = Builder.CreateStructGEP(loc, 0, "startPointer"); 1415234353Sdim llvm::Value *startAddress = Builder.CreateLoad(startPointer, "startAddress"); 1416234353Sdim 1417234353Sdim ::EmitRecursiveStdInitializerListCleanup(*this, startAddress, init); 1418234353Sdim 1419234353Sdim llvm::Value *arrayAddress = 1420234353Sdim Builder.CreateBitCast(startAddress, arrayPtrType, "arrayAddress"); 1421234353Sdim ::EmitStdInitializerListCleanup(*this, array, arrayAddress, init); 1422234353Sdim} 1423