CGExprAgg.cpp revision 199990
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" 19193326Sed#include "clang/AST/StmtVisitor.h" 20193326Sed#include "llvm/Constants.h" 21193326Sed#include "llvm/Function.h" 22193326Sed#include "llvm/GlobalVariable.h" 23193326Sed#include "llvm/Intrinsics.h" 24193326Sedusing namespace clang; 25193326Sedusing namespace CodeGen; 26193326Sed 27193326Sed//===----------------------------------------------------------------------===// 28193326Sed// Aggregate Expression Emitter 29193326Sed//===----------------------------------------------------------------------===// 30193326Sed 31193326Sednamespace { 32199990Srdivackyclass AggExprEmitter : public StmtVisitor<AggExprEmitter> { 33193326Sed CodeGenFunction &CGF; 34193326Sed CGBuilderTy &Builder; 35193326Sed llvm::Value *DestPtr; 36193326Sed bool VolatileDest; 37193326Sed bool IgnoreResult; 38198092Srdivacky bool IsInitializer; 39198092Srdivacky bool RequiresGCollection; 40193326Sedpublic: 41193326Sed AggExprEmitter(CodeGenFunction &cgf, llvm::Value *destPtr, bool v, 42198092Srdivacky bool ignore, bool isinit, bool requiresGCollection) 43193326Sed : CGF(cgf), Builder(CGF.Builder), 44198092Srdivacky DestPtr(destPtr), VolatileDest(v), IgnoreResult(ignore), 45198092Srdivacky IsInitializer(isinit), RequiresGCollection(requiresGCollection) { 46193326Sed } 47193326Sed 48193326Sed //===--------------------------------------------------------------------===// 49193326Sed // Utilities 50193326Sed //===--------------------------------------------------------------------===// 51193326Sed 52193326Sed /// EmitAggLoadOfLValue - Given an expression with aggregate type that 53193326Sed /// represents a value lvalue, this method emits the address of the lvalue, 54193326Sed /// then loads the result into DestPtr. 55193326Sed void EmitAggLoadOfLValue(const Expr *E); 56193326Sed 57193326Sed /// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired. 58193326Sed void EmitFinalDestCopy(const Expr *E, LValue Src, bool Ignore = false); 59193326Sed void EmitFinalDestCopy(const Expr *E, RValue Src, bool Ignore = false); 60193326Sed 61193326Sed //===--------------------------------------------------------------------===// 62193326Sed // Visitor Methods 63193326Sed //===--------------------------------------------------------------------===// 64198092Srdivacky 65193326Sed void VisitStmt(Stmt *S) { 66193326Sed CGF.ErrorUnsupported(S, "aggregate expression"); 67193326Sed } 68193326Sed void VisitParenExpr(ParenExpr *PE) { Visit(PE->getSubExpr()); } 69193326Sed void VisitUnaryExtension(UnaryOperator *E) { Visit(E->getSubExpr()); } 70193326Sed 71193326Sed // l-values. 72193326Sed void VisitDeclRefExpr(DeclRefExpr *DRE) { EmitAggLoadOfLValue(DRE); } 73193326Sed void VisitMemberExpr(MemberExpr *ME) { EmitAggLoadOfLValue(ME); } 74193326Sed void VisitUnaryDeref(UnaryOperator *E) { EmitAggLoadOfLValue(E); } 75193326Sed void VisitStringLiteral(StringLiteral *E) { EmitAggLoadOfLValue(E); } 76193326Sed void VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 77198092Srdivacky EmitAggLoadOfLValue(E); 78193326Sed } 79193326Sed void VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 80193326Sed EmitAggLoadOfLValue(E); 81193326Sed } 82193326Sed void VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 83198092Srdivacky EmitAggLoadOfLValue(E); 84193326Sed } 85193326Sed void VisitPredefinedExpr(const PredefinedExpr *E) { 86198092Srdivacky EmitAggLoadOfLValue(E); 87193326Sed } 88198092Srdivacky 89193326Sed // Operators. 90198092Srdivacky void VisitCastExpr(CastExpr *E); 91193326Sed void VisitCallExpr(const CallExpr *E); 92193326Sed void VisitStmtExpr(const StmtExpr *E); 93193326Sed void VisitBinaryOperator(const BinaryOperator *BO); 94198398Srdivacky void VisitPointerToDataMemberBinaryOperator(const BinaryOperator *BO); 95193326Sed void VisitBinAssign(const BinaryOperator *E); 96193326Sed void VisitBinComma(const BinaryOperator *E); 97198092Srdivacky void VisitUnaryAddrOf(const UnaryOperator *E); 98193326Sed 99193326Sed void VisitObjCMessageExpr(ObjCMessageExpr *E); 100193326Sed void VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 101193326Sed EmitAggLoadOfLValue(E); 102193326Sed } 103193326Sed void VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E); 104198092Srdivacky void VisitObjCImplicitSetterGetterRefExpr(ObjCImplicitSetterGetterRefExpr *E); 105198092Srdivacky 106193326Sed void VisitConditionalOperator(const ConditionalOperator *CO); 107198092Srdivacky void VisitChooseExpr(const ChooseExpr *CE); 108193326Sed void VisitInitListExpr(InitListExpr *E); 109193326Sed void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 110193326Sed Visit(DAE->getExpr()); 111193326Sed } 112193326Sed void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E); 113193326Sed void VisitCXXConstructExpr(const CXXConstructExpr *E); 114193326Sed void VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E); 115198398Srdivacky void VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E); 116199482Srdivacky void VisitCXXTypeidExpr(CXXTypeidExpr *E) { EmitAggLoadOfLValue(E); } 117193326Sed 118193326Sed void VisitVAArgExpr(VAArgExpr *E); 119193326Sed 120193326Sed void EmitInitializationToLValue(Expr *E, LValue Address); 121193326Sed void EmitNullInitializationToLValue(LValue Address, QualType T); 122193326Sed // case Expr::ChooseExprClass: 123193326Sed 124193326Sed}; 125193326Sed} // end anonymous namespace. 126193326Sed 127193326Sed//===----------------------------------------------------------------------===// 128193326Sed// Utilities 129193326Sed//===----------------------------------------------------------------------===// 130193326Sed 131193326Sed/// EmitAggLoadOfLValue - Given an expression with aggregate type that 132193326Sed/// represents a value lvalue, this method emits the address of the lvalue, 133193326Sed/// then loads the result into DestPtr. 134193326Sedvoid AggExprEmitter::EmitAggLoadOfLValue(const Expr *E) { 135193326Sed LValue LV = CGF.EmitLValue(E); 136193326Sed EmitFinalDestCopy(E, LV); 137193326Sed} 138193326Sed 139193326Sed/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired. 140193326Sedvoid AggExprEmitter::EmitFinalDestCopy(const Expr *E, RValue Src, bool Ignore) { 141193326Sed assert(Src.isAggregate() && "value must be aggregate value!"); 142193326Sed 143193326Sed // If the result is ignored, don't copy from the value. 144193326Sed if (DestPtr == 0) { 145193326Sed if (!Src.isVolatileQualified() || (IgnoreResult && Ignore)) 146193326Sed return; 147193326Sed // If the source is volatile, we must read from it; to do that, we need 148193326Sed // some place to put it. 149193326Sed DestPtr = CGF.CreateTempAlloca(CGF.ConvertType(E->getType()), "agg.tmp"); 150193326Sed } 151193326Sed 152198092Srdivacky if (RequiresGCollection) { 153198092Srdivacky CGF.CGM.getObjCRuntime().EmitGCMemmoveCollectable(CGF, 154198092Srdivacky DestPtr, Src.getAggregateAddr(), 155198092Srdivacky E->getType()); 156198092Srdivacky return; 157198092Srdivacky } 158193326Sed // If the result of the assignment is used, copy the LHS there also. 159193326Sed // FIXME: Pass VolatileDest as well. I think we also need to merge volatile 160193326Sed // from the source as well, as we can't eliminate it if either operand 161193326Sed // is volatile, unless copy has volatile for both source and destination.. 162193326Sed CGF.EmitAggregateCopy(DestPtr, Src.getAggregateAddr(), E->getType(), 163193326Sed VolatileDest|Src.isVolatileQualified()); 164193326Sed} 165193326Sed 166193326Sed/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired. 167193326Sedvoid AggExprEmitter::EmitFinalDestCopy(const Expr *E, LValue Src, bool Ignore) { 168193326Sed assert(Src.isSimple() && "Can't have aggregate bitfield, vector, etc"); 169193326Sed 170193326Sed EmitFinalDestCopy(E, RValue::getAggregate(Src.getAddress(), 171193326Sed Src.isVolatileQualified()), 172193326Sed Ignore); 173193326Sed} 174193326Sed 175193326Sed//===----------------------------------------------------------------------===// 176193326Sed// Visitor Methods 177193326Sed//===----------------------------------------------------------------------===// 178193326Sed 179198092Srdivackyvoid AggExprEmitter::VisitCastExpr(CastExpr *E) { 180198092Srdivacky switch (E->getCastKind()) { 181198092Srdivacky default: assert(0 && "Unhandled cast kind!"); 182198092Srdivacky 183198092Srdivacky case CastExpr::CK_ToUnion: { 184198092Srdivacky // GCC union extension 185193401Sed QualType PtrTy = 186198092Srdivacky CGF.getContext().getPointerType(E->getSubExpr()->getType()); 187193401Sed llvm::Value *CastPtr = Builder.CreateBitCast(DestPtr, 188193401Sed CGF.ConvertType(PtrTy)); 189198092Srdivacky EmitInitializationToLValue(E->getSubExpr(), 190198092Srdivacky LValue::MakeAddr(CastPtr, Qualifiers())); 191198092Srdivacky break; 192193326Sed } 193193326Sed 194198092Srdivacky // FIXME: Remove the CK_Unknown check here. 195198092Srdivacky case CastExpr::CK_Unknown: 196198092Srdivacky case CastExpr::CK_NoOp: 197198092Srdivacky case CastExpr::CK_UserDefinedConversion: 198198092Srdivacky case CastExpr::CK_ConstructorConversion: 199198092Srdivacky assert(CGF.getContext().hasSameUnqualifiedType(E->getSubExpr()->getType(), 200198092Srdivacky E->getType()) && 201198092Srdivacky "Implicit cast types must be compatible"); 202198092Srdivacky Visit(E->getSubExpr()); 203198092Srdivacky break; 204193326Sed 205198092Srdivacky case CastExpr::CK_NullToMemberPointer: { 206198092Srdivacky const llvm::Type *PtrDiffTy = 207198092Srdivacky CGF.ConvertType(CGF.getContext().getPointerDiffType()); 208198092Srdivacky 209198092Srdivacky llvm::Value *NullValue = llvm::Constant::getNullValue(PtrDiffTy); 210198092Srdivacky llvm::Value *Ptr = Builder.CreateStructGEP(DestPtr, 0, "ptr"); 211198092Srdivacky Builder.CreateStore(NullValue, Ptr, VolatileDest); 212198092Srdivacky 213198092Srdivacky llvm::Value *Adj = Builder.CreateStructGEP(DestPtr, 1, "adj"); 214198092Srdivacky Builder.CreateStore(NullValue, Adj, VolatileDest); 215198092Srdivacky 216198092Srdivacky break; 217198092Srdivacky } 218198092Srdivacky 219198398Srdivacky case CastExpr::CK_BitCast: { 220198398Srdivacky // This must be a member function pointer cast. 221198398Srdivacky Visit(E->getSubExpr()); 222198398Srdivacky break; 223198398Srdivacky } 224198398Srdivacky 225199990Srdivacky case CastExpr::CK_DerivedToBaseMemberPointer: 226198092Srdivacky case CastExpr::CK_BaseToDerivedMemberPointer: { 227198092Srdivacky QualType SrcType = E->getSubExpr()->getType(); 228198092Srdivacky 229198092Srdivacky llvm::Value *Src = CGF.CreateTempAlloca(CGF.ConvertTypeForMem(SrcType), 230198092Srdivacky "tmp"); 231198092Srdivacky CGF.EmitAggExpr(E->getSubExpr(), Src, SrcType.isVolatileQualified()); 232198092Srdivacky 233198092Srdivacky llvm::Value *SrcPtr = Builder.CreateStructGEP(Src, 0, "src.ptr"); 234198092Srdivacky SrcPtr = Builder.CreateLoad(SrcPtr); 235198092Srdivacky 236198092Srdivacky llvm::Value *SrcAdj = Builder.CreateStructGEP(Src, 1, "src.adj"); 237198092Srdivacky SrcAdj = Builder.CreateLoad(SrcAdj); 238198092Srdivacky 239198092Srdivacky llvm::Value *DstPtr = Builder.CreateStructGEP(DestPtr, 0, "dst.ptr"); 240198092Srdivacky Builder.CreateStore(SrcPtr, DstPtr, VolatileDest); 241198092Srdivacky 242198092Srdivacky llvm::Value *DstAdj = Builder.CreateStructGEP(DestPtr, 1, "dst.adj"); 243198092Srdivacky 244198092Srdivacky // Now See if we need to update the adjustment. 245199990Srdivacky const CXXRecordDecl *BaseDecl = 246198092Srdivacky cast<CXXRecordDecl>(SrcType->getAs<MemberPointerType>()-> 247198092Srdivacky getClass()->getAs<RecordType>()->getDecl()); 248199990Srdivacky const CXXRecordDecl *DerivedDecl = 249198092Srdivacky cast<CXXRecordDecl>(E->getType()->getAs<MemberPointerType>()-> 250198092Srdivacky getClass()->getAs<RecordType>()->getDecl()); 251199990Srdivacky if (E->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer) 252199990Srdivacky std::swap(DerivedDecl, BaseDecl); 253199990Srdivacky 254199990Srdivacky llvm::Constant *Adj = CGF.CGM.GetCXXBaseClassOffset(DerivedDecl, BaseDecl); 255199990Srdivacky if (Adj) { 256199990Srdivacky if (E->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer) 257199990Srdivacky SrcAdj = Builder.CreateSub(SrcAdj, Adj, "adj"); 258199990Srdivacky else 259199990Srdivacky SrcAdj = Builder.CreateAdd(SrcAdj, Adj, "adj"); 260199990Srdivacky } 261198092Srdivacky 262198092Srdivacky Builder.CreateStore(SrcAdj, DstAdj, VolatileDest); 263198092Srdivacky break; 264198092Srdivacky } 265198092Srdivacky } 266193326Sed} 267193326Sed 268193326Sedvoid AggExprEmitter::VisitCallExpr(const CallExpr *E) { 269193326Sed if (E->getCallReturnType()->isReferenceType()) { 270193326Sed EmitAggLoadOfLValue(E); 271193326Sed return; 272193326Sed } 273198092Srdivacky 274193326Sed RValue RV = CGF.EmitCallExpr(E); 275193326Sed EmitFinalDestCopy(E, RV); 276193326Sed} 277193326Sed 278193326Sedvoid AggExprEmitter::VisitObjCMessageExpr(ObjCMessageExpr *E) { 279193326Sed RValue RV = CGF.EmitObjCMessageExpr(E); 280193326Sed EmitFinalDestCopy(E, RV); 281193326Sed} 282193326Sed 283193326Sedvoid AggExprEmitter::VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 284193326Sed RValue RV = CGF.EmitObjCPropertyGet(E); 285193326Sed EmitFinalDestCopy(E, RV); 286193326Sed} 287193326Sed 288198092Srdivackyvoid AggExprEmitter::VisitObjCImplicitSetterGetterRefExpr( 289198092Srdivacky ObjCImplicitSetterGetterRefExpr *E) { 290193326Sed RValue RV = CGF.EmitObjCPropertyGet(E); 291193326Sed EmitFinalDestCopy(E, RV); 292193326Sed} 293193326Sed 294193326Sedvoid AggExprEmitter::VisitBinComma(const BinaryOperator *E) { 295193326Sed CGF.EmitAnyExpr(E->getLHS(), 0, false, true); 296198092Srdivacky CGF.EmitAggExpr(E->getRHS(), DestPtr, VolatileDest, 297198092Srdivacky /*IgnoreResult=*/false, IsInitializer); 298193326Sed} 299193326Sed 300198092Srdivackyvoid AggExprEmitter::VisitUnaryAddrOf(const UnaryOperator *E) { 301198092Srdivacky // We have a member function pointer. 302198092Srdivacky const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>(); 303198398Srdivacky (void) MPT; 304198092Srdivacky assert(MPT->getPointeeType()->isFunctionProtoType() && 305198092Srdivacky "Unexpected member pointer type!"); 306198092Srdivacky 307198893Srdivacky const DeclRefExpr *DRE = cast<DeclRefExpr>(E->getSubExpr()); 308198092Srdivacky const CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl()); 309198092Srdivacky 310198092Srdivacky const llvm::Type *PtrDiffTy = 311198092Srdivacky CGF.ConvertType(CGF.getContext().getPointerDiffType()); 312198092Srdivacky 313198092Srdivacky llvm::Value *DstPtr = Builder.CreateStructGEP(DestPtr, 0, "dst.ptr"); 314198092Srdivacky llvm::Value *FuncPtr; 315198092Srdivacky 316198092Srdivacky if (MD->isVirtual()) { 317198092Srdivacky int64_t Index = 318198092Srdivacky CGF.CGM.getVtableInfo().getMethodVtableIndex(MD); 319198092Srdivacky 320198092Srdivacky FuncPtr = llvm::ConstantInt::get(PtrDiffTy, Index + 1); 321198092Srdivacky } else { 322198092Srdivacky FuncPtr = llvm::ConstantExpr::getPtrToInt(CGF.CGM.GetAddrOfFunction(MD), 323198092Srdivacky PtrDiffTy); 324198092Srdivacky } 325198092Srdivacky Builder.CreateStore(FuncPtr, DstPtr, VolatileDest); 326198092Srdivacky 327198092Srdivacky llvm::Value *AdjPtr = Builder.CreateStructGEP(DestPtr, 1, "dst.adj"); 328198092Srdivacky 329198092Srdivacky // The adjustment will always be 0. 330198092Srdivacky Builder.CreateStore(llvm::ConstantInt::get(PtrDiffTy, 0), AdjPtr, 331198092Srdivacky VolatileDest); 332198092Srdivacky} 333198092Srdivacky 334193326Sedvoid AggExprEmitter::VisitStmtExpr(const StmtExpr *E) { 335193326Sed CGF.EmitCompoundStmt(*E->getSubStmt(), true, DestPtr, VolatileDest); 336193326Sed} 337193326Sed 338193326Sedvoid AggExprEmitter::VisitBinaryOperator(const BinaryOperator *E) { 339198893Srdivacky if (E->getOpcode() == BinaryOperator::PtrMemD || 340198893Srdivacky E->getOpcode() == BinaryOperator::PtrMemI) 341198398Srdivacky VisitPointerToDataMemberBinaryOperator(E); 342198398Srdivacky else 343198398Srdivacky CGF.ErrorUnsupported(E, "aggregate binary expression"); 344193326Sed} 345193326Sed 346198398Srdivackyvoid AggExprEmitter::VisitPointerToDataMemberBinaryOperator( 347198398Srdivacky const BinaryOperator *E) { 348198398Srdivacky LValue LV = CGF.EmitPointerToDataMemberBinaryExpr(E); 349198398Srdivacky EmitFinalDestCopy(E, LV); 350198398Srdivacky} 351198398Srdivacky 352193326Sedvoid AggExprEmitter::VisitBinAssign(const BinaryOperator *E) { 353193326Sed // For an assignment to work, the value on the right has 354193326Sed // to be compatible with the value on the left. 355193326Sed assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(), 356193326Sed E->getRHS()->getType()) 357193326Sed && "Invalid assignment"); 358193326Sed LValue LHS = CGF.EmitLValue(E->getLHS()); 359193326Sed 360193326Sed // We have to special case property setters, otherwise we must have 361193326Sed // a simple lvalue (no aggregates inside vectors, bitfields). 362193326Sed if (LHS.isPropertyRef()) { 363193326Sed llvm::Value *AggLoc = DestPtr; 364193326Sed if (!AggLoc) 365193326Sed AggLoc = CGF.CreateTempAlloca(CGF.ConvertType(E->getRHS()->getType())); 366193326Sed CGF.EmitAggExpr(E->getRHS(), AggLoc, VolatileDest); 367198092Srdivacky CGF.EmitObjCPropertySet(LHS.getPropertyRefExpr(), 368193326Sed RValue::getAggregate(AggLoc, VolatileDest)); 369198092Srdivacky } else if (LHS.isKVCRef()) { 370193326Sed llvm::Value *AggLoc = DestPtr; 371193326Sed if (!AggLoc) 372193326Sed AggLoc = CGF.CreateTempAlloca(CGF.ConvertType(E->getRHS()->getType())); 373193326Sed CGF.EmitAggExpr(E->getRHS(), AggLoc, VolatileDest); 374198092Srdivacky CGF.EmitObjCPropertySet(LHS.getKVCRefExpr(), 375193326Sed RValue::getAggregate(AggLoc, VolatileDest)); 376193326Sed } else { 377198092Srdivacky bool RequiresGCollection = false; 378198092Srdivacky if (CGF.getContext().getLangOptions().NeXTRuntime) { 379198092Srdivacky QualType LHSTy = E->getLHS()->getType(); 380198092Srdivacky if (const RecordType *FDTTy = LHSTy.getTypePtr()->getAs<RecordType>()) 381198092Srdivacky RequiresGCollection = FDTTy->getDecl()->hasObjectMember(); 382198092Srdivacky } 383193326Sed // Codegen the RHS so that it stores directly into the LHS. 384198092Srdivacky CGF.EmitAggExpr(E->getRHS(), LHS.getAddress(), LHS.isVolatileQualified(), 385198092Srdivacky false, false, RequiresGCollection); 386193326Sed EmitFinalDestCopy(E, LHS, true); 387193326Sed } 388193326Sed} 389193326Sed 390193326Sedvoid AggExprEmitter::VisitConditionalOperator(const ConditionalOperator *E) { 391193326Sed llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 392193326Sed llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 393193326Sed llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 394198092Srdivacky 395193326Sed llvm::Value *Cond = CGF.EvaluateExprAsBool(E->getCond()); 396193326Sed Builder.CreateCondBr(Cond, LHSBlock, RHSBlock); 397198092Srdivacky 398199990Srdivacky CGF.StartConditionalBranch(); 399193326Sed CGF.EmitBlock(LHSBlock); 400198092Srdivacky 401193326Sed // Handle the GNU extension for missing LHS. 402193326Sed assert(E->getLHS() && "Must have LHS for aggregate value"); 403193326Sed 404193326Sed Visit(E->getLHS()); 405199990Srdivacky CGF.FinishConditionalBranch(); 406193326Sed CGF.EmitBranch(ContBlock); 407198092Srdivacky 408199990Srdivacky CGF.StartConditionalBranch(); 409193326Sed CGF.EmitBlock(RHSBlock); 410198092Srdivacky 411193326Sed Visit(E->getRHS()); 412199990Srdivacky CGF.FinishConditionalBranch(); 413193326Sed CGF.EmitBranch(ContBlock); 414198092Srdivacky 415193326Sed CGF.EmitBlock(ContBlock); 416193326Sed} 417193326Sed 418198092Srdivackyvoid AggExprEmitter::VisitChooseExpr(const ChooseExpr *CE) { 419198092Srdivacky Visit(CE->getChosenSubExpr(CGF.getContext())); 420198092Srdivacky} 421198092Srdivacky 422193326Sedvoid AggExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 423193326Sed llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 424193326Sed llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 425193326Sed 426193326Sed if (!ArgPtr) { 427193326Sed CGF.ErrorUnsupported(VE, "aggregate va_arg expression"); 428193326Sed return; 429193326Sed } 430193326Sed 431198092Srdivacky EmitFinalDestCopy(VE, LValue::MakeAddr(ArgPtr, Qualifiers())); 432193326Sed} 433193326Sed 434193326Sedvoid AggExprEmitter::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) { 435193326Sed llvm::Value *Val = DestPtr; 436198092Srdivacky 437193326Sed if (!Val) { 438193326Sed // Create a temporary variable. 439193326Sed Val = CGF.CreateTempAlloca(CGF.ConvertTypeForMem(E->getType()), "tmp"); 440193326Sed 441193326Sed // FIXME: volatile 442193326Sed CGF.EmitAggExpr(E->getSubExpr(), Val, false); 443198092Srdivacky } else 444193326Sed Visit(E->getSubExpr()); 445198092Srdivacky 446198092Srdivacky // Don't make this a live temporary if we're emitting an initializer expr. 447198092Srdivacky if (!IsInitializer) 448198092Srdivacky CGF.PushCXXTemporary(E->getTemporary(), Val); 449193326Sed} 450193326Sed 451193326Sedvoid 452193326SedAggExprEmitter::VisitCXXConstructExpr(const CXXConstructExpr *E) { 453193326Sed llvm::Value *Val = DestPtr; 454198092Srdivacky 455193326Sed if (!Val) { 456193326Sed // Create a temporary variable. 457193326Sed Val = CGF.CreateTempAlloca(CGF.ConvertTypeForMem(E->getType()), "tmp"); 458193326Sed } 459193326Sed 460193326Sed CGF.EmitCXXConstructExpr(Val, E); 461193326Sed} 462193326Sed 463193326Sedvoid AggExprEmitter::VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) { 464198092Srdivacky CGF.EmitCXXExprWithTemporaries(E, DestPtr, VolatileDest, IsInitializer); 465193326Sed} 466193326Sed 467198398Srdivackyvoid AggExprEmitter::VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E) { 468198398Srdivacky LValue lvalue = LValue::MakeAddr(DestPtr, Qualifiers()); 469198398Srdivacky EmitNullInitializationToLValue(lvalue, E->getType()); 470198398Srdivacky} 471198398Srdivacky 472193326Sedvoid AggExprEmitter::EmitInitializationToLValue(Expr* E, LValue LV) { 473193326Sed // FIXME: Ignore result? 474193326Sed // FIXME: Are initializers affected by volatile? 475193326Sed if (isa<ImplicitValueInitExpr>(E)) { 476193326Sed EmitNullInitializationToLValue(LV, E->getType()); 477193326Sed } else if (E->getType()->isComplexType()) { 478193326Sed CGF.EmitComplexExprIntoAddr(E, LV.getAddress(), false); 479193326Sed } else if (CGF.hasAggregateLLVMType(E->getType())) { 480193326Sed CGF.EmitAnyExpr(E, LV.getAddress(), false); 481193326Sed } else { 482193326Sed CGF.EmitStoreThroughLValue(CGF.EmitAnyExpr(E), LV, E->getType()); 483193326Sed } 484193326Sed} 485193326Sed 486193326Sedvoid AggExprEmitter::EmitNullInitializationToLValue(LValue LV, QualType T) { 487193326Sed if (!CGF.hasAggregateLLVMType(T)) { 488193326Sed // For non-aggregates, we can store zero 489193326Sed llvm::Value *Null = llvm::Constant::getNullValue(CGF.ConvertType(T)); 490193326Sed CGF.EmitStoreThroughLValue(RValue::get(Null), LV, T); 491193326Sed } else { 492193326Sed // Otherwise, just memset the whole thing to zero. This is legal 493193326Sed // because in LLVM, all default initializers are guaranteed to have a 494193326Sed // bit pattern of all zeros. 495193326Sed // FIXME: That isn't true for member pointers! 496193326Sed // There's a potential optimization opportunity in combining 497193326Sed // memsets; that would be easy for arrays, but relatively 498193326Sed // difficult for structures with the current code. 499193326Sed CGF.EmitMemSetToZero(LV.getAddress(), T); 500193326Sed } 501193326Sed} 502193326Sed 503193326Sedvoid AggExprEmitter::VisitInitListExpr(InitListExpr *E) { 504193326Sed#if 0 505198092Srdivacky // FIXME: Disabled while we figure out what to do about 506193326Sed // test/CodeGen/bitfield.c 507193326Sed // 508193326Sed // If we can, prefer a copy from a global; this is a lot less code for long 509193326Sed // globals, and it's easier for the current optimizers to analyze. 510193326Sed // FIXME: Should we really be doing this? Should we try to avoid cases where 511193326Sed // we emit a global with a lot of zeros? Should we try to avoid short 512193326Sed // globals? 513193326Sed if (E->isConstantInitializer(CGF.getContext(), 0)) { 514193326Sed llvm::Constant* C = CGF.CGM.EmitConstantExpr(E, &CGF); 515193326Sed llvm::GlobalVariable* GV = 516193326Sed new llvm::GlobalVariable(C->getType(), true, 517193326Sed llvm::GlobalValue::InternalLinkage, 518193326Sed C, "", &CGF.CGM.getModule(), 0); 519193326Sed EmitFinalDestCopy(E, LValue::MakeAddr(GV, 0)); 520193326Sed return; 521193326Sed } 522193326Sed#endif 523193326Sed if (E->hadArrayRangeDesignator()) { 524193326Sed CGF.ErrorUnsupported(E, "GNU array range designator extension"); 525193326Sed } 526193326Sed 527193326Sed // Handle initialization of an array. 528193326Sed if (E->getType()->isArrayType()) { 529193326Sed const llvm::PointerType *APType = 530193326Sed cast<llvm::PointerType>(DestPtr->getType()); 531193326Sed const llvm::ArrayType *AType = 532193326Sed cast<llvm::ArrayType>(APType->getElementType()); 533198092Srdivacky 534193326Sed uint64_t NumInitElements = E->getNumInits(); 535193326Sed 536193326Sed if (E->getNumInits() > 0) { 537193326Sed QualType T1 = E->getType(); 538193326Sed QualType T2 = E->getInit(0)->getType(); 539193326Sed if (CGF.getContext().hasSameUnqualifiedType(T1, T2)) { 540193326Sed EmitAggLoadOfLValue(E->getInit(0)); 541193326Sed return; 542193326Sed } 543193326Sed } 544193326Sed 545193326Sed uint64_t NumArrayElements = AType->getNumElements(); 546193326Sed QualType ElementType = CGF.getContext().getCanonicalType(E->getType()); 547193326Sed ElementType = CGF.getContext().getAsArrayType(ElementType)->getElementType(); 548193326Sed 549198092Srdivacky // FIXME: were we intentionally ignoring address spaces and GC attributes? 550198092Srdivacky Qualifiers Quals = CGF.MakeQualifiers(ElementType); 551198092Srdivacky 552193326Sed for (uint64_t i = 0; i != NumArrayElements; ++i) { 553193326Sed llvm::Value *NextVal = Builder.CreateStructGEP(DestPtr, i, ".array"); 554193326Sed if (i < NumInitElements) 555193326Sed EmitInitializationToLValue(E->getInit(i), 556198092Srdivacky LValue::MakeAddr(NextVal, Quals)); 557193326Sed else 558198092Srdivacky EmitNullInitializationToLValue(LValue::MakeAddr(NextVal, Quals), 559193326Sed ElementType); 560193326Sed } 561193326Sed return; 562193326Sed } 563198092Srdivacky 564193326Sed assert(E->getType()->isRecordType() && "Only support structs/unions here!"); 565198092Srdivacky 566193326Sed // Do struct initialization; this code just sets each individual member 567193326Sed // to the approprate value. This makes bitfield support automatic; 568193326Sed // the disadvantage is that the generated code is more difficult for 569193326Sed // the optimizer, especially with bitfields. 570193326Sed unsigned NumInitElements = E->getNumInits(); 571198092Srdivacky RecordDecl *SD = E->getType()->getAs<RecordType>()->getDecl(); 572193326Sed unsigned CurInitVal = 0; 573193326Sed 574193326Sed if (E->getType()->isUnionType()) { 575193326Sed // Only initialize one field of a union. The field itself is 576193326Sed // specified by the initializer list. 577193326Sed if (!E->getInitializedFieldInUnion()) { 578193326Sed // Empty union; we have nothing to do. 579198092Srdivacky 580193326Sed#ifndef NDEBUG 581193326Sed // Make sure that it's really an empty and not a failure of 582193326Sed // semantic analysis. 583195341Sed for (RecordDecl::field_iterator Field = SD->field_begin(), 584195341Sed FieldEnd = SD->field_end(); 585193326Sed Field != FieldEnd; ++Field) 586193326Sed assert(Field->isUnnamedBitfield() && "Only unnamed bitfields allowed"); 587193326Sed#endif 588193326Sed return; 589193326Sed } 590193326Sed 591193326Sed // FIXME: volatility 592193326Sed FieldDecl *Field = E->getInitializedFieldInUnion(); 593193326Sed LValue FieldLoc = CGF.EmitLValueForField(DestPtr, Field, true, 0); 594193326Sed 595193326Sed if (NumInitElements) { 596193326Sed // Store the initializer into the field 597193326Sed EmitInitializationToLValue(E->getInit(0), FieldLoc); 598193326Sed } else { 599193326Sed // Default-initialize to null 600193326Sed EmitNullInitializationToLValue(FieldLoc, Field->getType()); 601193326Sed } 602193326Sed 603193326Sed return; 604193326Sed } 605198092Srdivacky 606193326Sed // Here we iterate over the fields; this makes it simpler to both 607193326Sed // default-initialize fields and skip over unnamed fields. 608195341Sed for (RecordDecl::field_iterator Field = SD->field_begin(), 609195341Sed FieldEnd = SD->field_end(); 610193326Sed Field != FieldEnd; ++Field) { 611193326Sed // We're done once we hit the flexible array member 612193326Sed if (Field->getType()->isIncompleteArrayType()) 613193326Sed break; 614193326Sed 615193326Sed if (Field->isUnnamedBitfield()) 616193326Sed continue; 617193326Sed 618193326Sed // FIXME: volatility 619193326Sed LValue FieldLoc = CGF.EmitLValueForField(DestPtr, *Field, false, 0); 620193326Sed // We never generate write-barries for initialized fields. 621193326Sed LValue::SetObjCNonGC(FieldLoc, true); 622193326Sed if (CurInitVal < NumInitElements) { 623193326Sed // Store the initializer into the field 624193326Sed EmitInitializationToLValue(E->getInit(CurInitVal++), FieldLoc); 625193326Sed } else { 626193326Sed // We're out of initalizers; default-initialize to null 627193326Sed EmitNullInitializationToLValue(FieldLoc, Field->getType()); 628193326Sed } 629193326Sed } 630193326Sed} 631193326Sed 632193326Sed//===----------------------------------------------------------------------===// 633193326Sed// Entry Points into this File 634193326Sed//===----------------------------------------------------------------------===// 635193326Sed 636193326Sed/// EmitAggExpr - Emit the computation of the specified expression of aggregate 637193326Sed/// type. The result is computed into DestPtr. Note that if DestPtr is null, 638193326Sed/// the value of the aggregate expression is not needed. If VolatileDest is 639193326Sed/// true, DestPtr cannot be 0. 640193326Sedvoid CodeGenFunction::EmitAggExpr(const Expr *E, llvm::Value *DestPtr, 641198092Srdivacky bool VolatileDest, bool IgnoreResult, 642198092Srdivacky bool IsInitializer, 643198092Srdivacky bool RequiresGCollection) { 644193326Sed assert(E && hasAggregateLLVMType(E->getType()) && 645193326Sed "Invalid aggregate expression to emit"); 646193326Sed assert ((DestPtr != 0 || VolatileDest == false) 647193326Sed && "volatile aggregate can't be 0"); 648198092Srdivacky 649198092Srdivacky AggExprEmitter(*this, DestPtr, VolatileDest, IgnoreResult, IsInitializer, 650198092Srdivacky RequiresGCollection) 651193326Sed .Visit(const_cast<Expr*>(E)); 652193326Sed} 653193326Sed 654193326Sedvoid CodeGenFunction::EmitAggregateClear(llvm::Value *DestPtr, QualType Ty) { 655193326Sed assert(!Ty->isAnyComplexType() && "Shouldn't happen for complex"); 656193326Sed 657193326Sed EmitMemSetToZero(DestPtr, Ty); 658193326Sed} 659193326Sed 660193326Sedvoid CodeGenFunction::EmitAggregateCopy(llvm::Value *DestPtr, 661193326Sed llvm::Value *SrcPtr, QualType Ty, 662193326Sed bool isVolatile) { 663193326Sed assert(!Ty->isAnyComplexType() && "Shouldn't happen for complex"); 664198092Srdivacky 665193326Sed // Aggregate assignment turns into llvm.memcpy. This is almost valid per 666193326Sed // C99 6.5.16.1p3, which states "If the value being stored in an object is 667193326Sed // read from another object that overlaps in anyway the storage of the first 668193326Sed // object, then the overlap shall be exact and the two objects shall have 669193326Sed // qualified or unqualified versions of a compatible type." 670193326Sed // 671193326Sed // memcpy is not defined if the source and destination pointers are exactly 672193326Sed // equal, but other compilers do this optimization, and almost every memcpy 673193326Sed // implementation handles this case safely. If there is a libc that does not 674193326Sed // safely handle this, we can add a target hook. 675198092Srdivacky const llvm::Type *BP = llvm::Type::getInt8PtrTy(VMContext); 676193326Sed if (DestPtr->getType() != BP) 677193326Sed DestPtr = Builder.CreateBitCast(DestPtr, BP, "tmp"); 678193326Sed if (SrcPtr->getType() != BP) 679193326Sed SrcPtr = Builder.CreateBitCast(SrcPtr, BP, "tmp"); 680198092Srdivacky 681193326Sed // Get size and alignment info for this aggregate. 682193326Sed std::pair<uint64_t, unsigned> TypeInfo = getContext().getTypeInfo(Ty); 683198092Srdivacky 684193326Sed // FIXME: Handle variable sized types. 685198092Srdivacky const llvm::Type *IntPtr = 686198092Srdivacky llvm::IntegerType::get(VMContext, LLVMPointerWidth); 687198092Srdivacky 688193326Sed // FIXME: If we have a volatile struct, the optimizer can remove what might 689193326Sed // appear to be `extra' memory ops: 690193326Sed // 691193326Sed // volatile struct { int i; } a, b; 692193326Sed // 693193326Sed // int main() { 694193326Sed // a = b; 695193326Sed // a = b; 696193326Sed // } 697193326Sed // 698193326Sed // we need to use a differnt call here. We use isVolatile to indicate when 699193326Sed // either the source or the destination is volatile. 700193326Sed Builder.CreateCall4(CGM.getMemCpyFn(), 701193326Sed DestPtr, SrcPtr, 702193326Sed // TypeInfo.first describes size in bits. 703193326Sed llvm::ConstantInt::get(IntPtr, TypeInfo.first/8), 704198092Srdivacky llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 705193326Sed TypeInfo.second/8)); 706193326Sed} 707