Check in LLVM r95781.
diff --git a/lib/CodeGen/CGExprAgg.cpp b/lib/CodeGen/CGExprAgg.cpp
new file mode 100644
index 0000000..97455c7
--- /dev/null
+++ b/lib/CodeGen/CGExprAgg.cpp
@@ -0,0 +1,767 @@
+//===--- CGExprAgg.cpp - Emit LLVM Code from Aggregate Expressions --------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This contains code to emit Aggregate Expr nodes as LLVM code.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CodeGenFunction.h"
+#include "CodeGenModule.h"
+#include "CGObjCRuntime.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/StmtVisitor.h"
+#include "llvm/Constants.h"
+#include "llvm/Function.h"
+#include "llvm/GlobalVariable.h"
+#include "llvm/Intrinsics.h"
+using namespace clang;
+using namespace CodeGen;
+
+//===----------------------------------------------------------------------===//
+// Aggregate Expression Emitter
+//===----------------------------------------------------------------------===//
+
+namespace {
+class AggExprEmitter : public StmtVisitor<AggExprEmitter> {
+ CodeGenFunction &CGF;
+ CGBuilderTy &Builder;
+ llvm::Value *DestPtr;
+ bool VolatileDest;
+ bool IgnoreResult;
+ bool IsInitializer;
+ bool RequiresGCollection;
+public:
+ AggExprEmitter(CodeGenFunction &cgf, llvm::Value *destPtr, bool v,
+ bool ignore, bool isinit, bool requiresGCollection)
+ : CGF(cgf), Builder(CGF.Builder),
+ DestPtr(destPtr), VolatileDest(v), IgnoreResult(ignore),
+ IsInitializer(isinit), RequiresGCollection(requiresGCollection) {
+ }
+
+ //===--------------------------------------------------------------------===//
+ // Utilities
+ //===--------------------------------------------------------------------===//
+
+ /// EmitAggLoadOfLValue - Given an expression with aggregate type that
+ /// represents a value lvalue, this method emits the address of the lvalue,
+ /// then loads the result into DestPtr.
+ void EmitAggLoadOfLValue(const Expr *E);
+
+ /// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired.
+ void EmitFinalDestCopy(const Expr *E, LValue Src, bool Ignore = false);
+ void EmitFinalDestCopy(const Expr *E, RValue Src, bool Ignore = false);
+
+ //===--------------------------------------------------------------------===//
+ // Visitor Methods
+ //===--------------------------------------------------------------------===//
+
+ void VisitStmt(Stmt *S) {
+ CGF.ErrorUnsupported(S, "aggregate expression");
+ }
+ void VisitParenExpr(ParenExpr *PE) { Visit(PE->getSubExpr()); }
+ void VisitUnaryExtension(UnaryOperator *E) { Visit(E->getSubExpr()); }
+
+ // l-values.
+ void VisitDeclRefExpr(DeclRefExpr *DRE) { EmitAggLoadOfLValue(DRE); }
+ void VisitMemberExpr(MemberExpr *ME) { EmitAggLoadOfLValue(ME); }
+ void VisitUnaryDeref(UnaryOperator *E) { EmitAggLoadOfLValue(E); }
+ void VisitStringLiteral(StringLiteral *E) { EmitAggLoadOfLValue(E); }
+ void VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
+ EmitAggLoadOfLValue(E);
+ }
+ void VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
+ EmitAggLoadOfLValue(E);
+ }
+ void VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) {
+ EmitAggLoadOfLValue(E);
+ }
+ void VisitPredefinedExpr(const PredefinedExpr *E) {
+ EmitAggLoadOfLValue(E);
+ }
+
+ // Operators.
+ void VisitCastExpr(CastExpr *E);
+ void VisitCallExpr(const CallExpr *E);
+ void VisitStmtExpr(const StmtExpr *E);
+ void VisitBinaryOperator(const BinaryOperator *BO);
+ void VisitPointerToDataMemberBinaryOperator(const BinaryOperator *BO);
+ void VisitBinAssign(const BinaryOperator *E);
+ void VisitBinComma(const BinaryOperator *E);
+ void VisitUnaryAddrOf(const UnaryOperator *E);
+
+ void VisitObjCMessageExpr(ObjCMessageExpr *E);
+ void VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
+ EmitAggLoadOfLValue(E);
+ }
+ void VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E);
+ void VisitObjCImplicitSetterGetterRefExpr(ObjCImplicitSetterGetterRefExpr *E);
+
+ void VisitConditionalOperator(const ConditionalOperator *CO);
+ void VisitChooseExpr(const ChooseExpr *CE);
+ void VisitInitListExpr(InitListExpr *E);
+ void VisitImplicitValueInitExpr(ImplicitValueInitExpr *E);
+ void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
+ Visit(DAE->getExpr());
+ }
+ void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E);
+ void VisitCXXConstructExpr(const CXXConstructExpr *E);
+ void VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E);
+ void VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E);
+ void VisitCXXTypeidExpr(CXXTypeidExpr *E) { EmitAggLoadOfLValue(E); }
+
+ void VisitVAArgExpr(VAArgExpr *E);
+
+ void EmitInitializationToLValue(Expr *E, LValue Address, QualType T);
+ void EmitNullInitializationToLValue(LValue Address, QualType T);
+ // case Expr::ChooseExprClass:
+ void VisitCXXThrowExpr(const CXXThrowExpr *E) { CGF.EmitCXXThrowExpr(E); }
+};
+} // end anonymous namespace.
+
+//===----------------------------------------------------------------------===//
+// Utilities
+//===----------------------------------------------------------------------===//
+
+/// EmitAggLoadOfLValue - Given an expression with aggregate type that
+/// represents a value lvalue, this method emits the address of the lvalue,
+/// then loads the result into DestPtr.
+void AggExprEmitter::EmitAggLoadOfLValue(const Expr *E) {
+ LValue LV = CGF.EmitLValue(E);
+ EmitFinalDestCopy(E, LV);
+}
+
+/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired.
+void AggExprEmitter::EmitFinalDestCopy(const Expr *E, RValue Src, bool Ignore) {
+ assert(Src.isAggregate() && "value must be aggregate value!");
+
+ // If the result is ignored, don't copy from the value.
+ if (DestPtr == 0) {
+ if (!Src.isVolatileQualified() || (IgnoreResult && Ignore))
+ return;
+ // If the source is volatile, we must read from it; to do that, we need
+ // some place to put it.
+ DestPtr = CGF.CreateMemTemp(E->getType(), "agg.tmp");
+ }
+
+ if (RequiresGCollection) {
+ CGF.CGM.getObjCRuntime().EmitGCMemmoveCollectable(CGF,
+ DestPtr, Src.getAggregateAddr(),
+ E->getType());
+ return;
+ }
+ // If the result of the assignment is used, copy the LHS there also.
+ // FIXME: Pass VolatileDest as well. I think we also need to merge volatile
+ // from the source as well, as we can't eliminate it if either operand
+ // is volatile, unless copy has volatile for both source and destination..
+ CGF.EmitAggregateCopy(DestPtr, Src.getAggregateAddr(), E->getType(),
+ VolatileDest|Src.isVolatileQualified());
+}
+
+/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired.
+void AggExprEmitter::EmitFinalDestCopy(const Expr *E, LValue Src, bool Ignore) {
+ assert(Src.isSimple() && "Can't have aggregate bitfield, vector, etc");
+
+ EmitFinalDestCopy(E, RValue::getAggregate(Src.getAddress(),
+ Src.isVolatileQualified()),
+ Ignore);
+}
+
+//===----------------------------------------------------------------------===//
+// Visitor Methods
+//===----------------------------------------------------------------------===//
+
+void AggExprEmitter::VisitCastExpr(CastExpr *E) {
+ switch (E->getCastKind()) {
+ default: assert(0 && "Unhandled cast kind!");
+
+ case CastExpr::CK_ToUnion: {
+ // GCC union extension
+ QualType PtrTy =
+ CGF.getContext().getPointerType(E->getSubExpr()->getType());
+ llvm::Value *CastPtr = Builder.CreateBitCast(DestPtr,
+ CGF.ConvertType(PtrTy));
+ EmitInitializationToLValue(E->getSubExpr(),
+ LValue::MakeAddr(CastPtr, Qualifiers()),
+ E->getType());
+ break;
+ }
+
+ // FIXME: Remove the CK_Unknown check here.
+ case CastExpr::CK_Unknown:
+ case CastExpr::CK_NoOp:
+ case CastExpr::CK_UserDefinedConversion:
+ case CastExpr::CK_ConstructorConversion:
+ assert(CGF.getContext().hasSameUnqualifiedType(E->getSubExpr()->getType(),
+ E->getType()) &&
+ "Implicit cast types must be compatible");
+ Visit(E->getSubExpr());
+ break;
+
+ case CastExpr::CK_NullToMemberPointer: {
+ const llvm::Type *PtrDiffTy =
+ CGF.ConvertType(CGF.getContext().getPointerDiffType());
+
+ llvm::Value *NullValue = llvm::Constant::getNullValue(PtrDiffTy);
+ llvm::Value *Ptr = Builder.CreateStructGEP(DestPtr, 0, "ptr");
+ Builder.CreateStore(NullValue, Ptr, VolatileDest);
+
+ llvm::Value *Adj = Builder.CreateStructGEP(DestPtr, 1, "adj");
+ Builder.CreateStore(NullValue, Adj, VolatileDest);
+
+ break;
+ }
+
+ case CastExpr::CK_BitCast: {
+ // This must be a member function pointer cast.
+ Visit(E->getSubExpr());
+ break;
+ }
+
+ case CastExpr::CK_DerivedToBaseMemberPointer:
+ case CastExpr::CK_BaseToDerivedMemberPointer: {
+ QualType SrcType = E->getSubExpr()->getType();
+
+ llvm::Value *Src = CGF.CreateMemTemp(SrcType, "tmp");
+ CGF.EmitAggExpr(E->getSubExpr(), Src, SrcType.isVolatileQualified());
+
+ llvm::Value *SrcPtr = Builder.CreateStructGEP(Src, 0, "src.ptr");
+ SrcPtr = Builder.CreateLoad(SrcPtr);
+
+ llvm::Value *SrcAdj = Builder.CreateStructGEP(Src, 1, "src.adj");
+ SrcAdj = Builder.CreateLoad(SrcAdj);
+
+ llvm::Value *DstPtr = Builder.CreateStructGEP(DestPtr, 0, "dst.ptr");
+ Builder.CreateStore(SrcPtr, DstPtr, VolatileDest);
+
+ llvm::Value *DstAdj = Builder.CreateStructGEP(DestPtr, 1, "dst.adj");
+
+ // Now See if we need to update the adjustment.
+ const CXXRecordDecl *BaseDecl =
+ cast<CXXRecordDecl>(SrcType->getAs<MemberPointerType>()->
+ getClass()->getAs<RecordType>()->getDecl());
+ const CXXRecordDecl *DerivedDecl =
+ cast<CXXRecordDecl>(E->getType()->getAs<MemberPointerType>()->
+ getClass()->getAs<RecordType>()->getDecl());
+ if (E->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer)
+ std::swap(DerivedDecl, BaseDecl);
+
+ if (llvm::Constant *Adj =
+ CGF.CGM.GetNonVirtualBaseClassOffset(DerivedDecl, BaseDecl)) {
+ if (E->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer)
+ SrcAdj = Builder.CreateSub(SrcAdj, Adj, "adj");
+ else
+ SrcAdj = Builder.CreateAdd(SrcAdj, Adj, "adj");
+ }
+
+ Builder.CreateStore(SrcAdj, DstAdj, VolatileDest);
+ break;
+ }
+ }
+}
+
+void AggExprEmitter::VisitCallExpr(const CallExpr *E) {
+ if (E->getCallReturnType()->isReferenceType()) {
+ EmitAggLoadOfLValue(E);
+ return;
+ }
+
+ // If the struct doesn't require GC, we can just pass the destination
+ // directly to EmitCall.
+ if (!RequiresGCollection) {
+ CGF.EmitCallExpr(E, ReturnValueSlot(DestPtr, VolatileDest));
+ return;
+ }
+
+ RValue RV = CGF.EmitCallExpr(E);
+ EmitFinalDestCopy(E, RV);
+}
+
+void AggExprEmitter::VisitObjCMessageExpr(ObjCMessageExpr *E) {
+ RValue RV = CGF.EmitObjCMessageExpr(E);
+ EmitFinalDestCopy(E, RV);
+}
+
+void AggExprEmitter::VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) {
+ RValue RV = CGF.EmitObjCPropertyGet(E);
+ EmitFinalDestCopy(E, RV);
+}
+
+void AggExprEmitter::VisitObjCImplicitSetterGetterRefExpr(
+ ObjCImplicitSetterGetterRefExpr *E) {
+ RValue RV = CGF.EmitObjCPropertyGet(E);
+ EmitFinalDestCopy(E, RV);
+}
+
+void AggExprEmitter::VisitBinComma(const BinaryOperator *E) {
+ CGF.EmitAnyExpr(E->getLHS(), 0, false, true);
+ CGF.EmitAggExpr(E->getRHS(), DestPtr, VolatileDest,
+ /*IgnoreResult=*/false, IsInitializer);
+}
+
+void AggExprEmitter::VisitUnaryAddrOf(const UnaryOperator *E) {
+ // We have a member function pointer.
+ const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>();
+ (void) MPT;
+ assert(MPT->getPointeeType()->isFunctionProtoType() &&
+ "Unexpected member pointer type!");
+
+ const DeclRefExpr *DRE = cast<DeclRefExpr>(E->getSubExpr());
+ const CXXMethodDecl *MD =
+ cast<CXXMethodDecl>(DRE->getDecl())->getCanonicalDecl();
+
+ const llvm::Type *PtrDiffTy =
+ CGF.ConvertType(CGF.getContext().getPointerDiffType());
+
+ llvm::Value *DstPtr = Builder.CreateStructGEP(DestPtr, 0, "dst.ptr");
+ llvm::Value *FuncPtr;
+
+ if (MD->isVirtual()) {
+ int64_t Index =
+ CGF.CGM.getVtableInfo().getMethodVtableIndex(MD);
+
+ // Itanium C++ ABI 2.3:
+ // For a non-virtual function, this field is a simple function pointer.
+ // For a virtual function, it is 1 plus the virtual table offset
+ // (in bytes) of the function, represented as a ptrdiff_t.
+ FuncPtr = llvm::ConstantInt::get(PtrDiffTy, (Index * 8) + 1);
+ } else {
+ const FunctionProtoType *FPT = MD->getType()->getAs<FunctionProtoType>();
+ const llvm::Type *Ty =
+ CGF.CGM.getTypes().GetFunctionType(CGF.CGM.getTypes().getFunctionInfo(MD),
+ FPT->isVariadic());
+ llvm::Constant *Fn = CGF.CGM.GetAddrOfFunction(MD, Ty);
+ FuncPtr = llvm::ConstantExpr::getPtrToInt(Fn, PtrDiffTy);
+ }
+ Builder.CreateStore(FuncPtr, DstPtr, VolatileDest);
+
+ llvm::Value *AdjPtr = Builder.CreateStructGEP(DestPtr, 1, "dst.adj");
+
+ // The adjustment will always be 0.
+ Builder.CreateStore(llvm::ConstantInt::get(PtrDiffTy, 0), AdjPtr,
+ VolatileDest);
+}
+
+void AggExprEmitter::VisitStmtExpr(const StmtExpr *E) {
+ CGF.EmitCompoundStmt(*E->getSubStmt(), true, DestPtr, VolatileDest);
+}
+
+void AggExprEmitter::VisitBinaryOperator(const BinaryOperator *E) {
+ if (E->getOpcode() == BinaryOperator::PtrMemD ||
+ E->getOpcode() == BinaryOperator::PtrMemI)
+ VisitPointerToDataMemberBinaryOperator(E);
+ else
+ CGF.ErrorUnsupported(E, "aggregate binary expression");
+}
+
+void AggExprEmitter::VisitPointerToDataMemberBinaryOperator(
+ const BinaryOperator *E) {
+ LValue LV = CGF.EmitPointerToDataMemberBinaryExpr(E);
+ EmitFinalDestCopy(E, LV);
+}
+
+void AggExprEmitter::VisitBinAssign(const BinaryOperator *E) {
+ // For an assignment to work, the value on the right has
+ // to be compatible with the value on the left.
+ assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(),
+ E->getRHS()->getType())
+ && "Invalid assignment");
+ LValue LHS = CGF.EmitLValue(E->getLHS());
+
+ // We have to special case property setters, otherwise we must have
+ // a simple lvalue (no aggregates inside vectors, bitfields).
+ if (LHS.isPropertyRef()) {
+ llvm::Value *AggLoc = DestPtr;
+ if (!AggLoc)
+ AggLoc = CGF.CreateMemTemp(E->getRHS()->getType());
+ CGF.EmitAggExpr(E->getRHS(), AggLoc, VolatileDest);
+ CGF.EmitObjCPropertySet(LHS.getPropertyRefExpr(),
+ RValue::getAggregate(AggLoc, VolatileDest));
+ } else if (LHS.isKVCRef()) {
+ llvm::Value *AggLoc = DestPtr;
+ if (!AggLoc)
+ AggLoc = CGF.CreateMemTemp(E->getRHS()->getType());
+ CGF.EmitAggExpr(E->getRHS(), AggLoc, VolatileDest);
+ CGF.EmitObjCPropertySet(LHS.getKVCRefExpr(),
+ RValue::getAggregate(AggLoc, VolatileDest));
+ } else {
+ bool RequiresGCollection = false;
+ if (CGF.getContext().getLangOptions().NeXTRuntime) {
+ QualType LHSTy = E->getLHS()->getType();
+ if (const RecordType *FDTTy = LHSTy.getTypePtr()->getAs<RecordType>())
+ RequiresGCollection = FDTTy->getDecl()->hasObjectMember();
+ }
+ // Codegen the RHS so that it stores directly into the LHS.
+ CGF.EmitAggExpr(E->getRHS(), LHS.getAddress(), LHS.isVolatileQualified(),
+ false, false, RequiresGCollection);
+ EmitFinalDestCopy(E, LHS, true);
+ }
+}
+
+void AggExprEmitter::VisitConditionalOperator(const ConditionalOperator *E) {
+ if (!E->getLHS()) {
+ CGF.ErrorUnsupported(E, "conditional operator with missing LHS");
+ return;
+ }
+
+ llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
+ llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
+ llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
+
+ CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);
+
+ CGF.BeginConditionalBranch();
+ CGF.EmitBlock(LHSBlock);
+
+ // Handle the GNU extension for missing LHS.
+ assert(E->getLHS() && "Must have LHS for aggregate value");
+
+ Visit(E->getLHS());
+ CGF.EndConditionalBranch();
+ CGF.EmitBranch(ContBlock);
+
+ CGF.BeginConditionalBranch();
+ CGF.EmitBlock(RHSBlock);
+
+ Visit(E->getRHS());
+ CGF.EndConditionalBranch();
+ CGF.EmitBranch(ContBlock);
+
+ CGF.EmitBlock(ContBlock);
+}
+
+void AggExprEmitter::VisitChooseExpr(const ChooseExpr *CE) {
+ Visit(CE->getChosenSubExpr(CGF.getContext()));
+}
+
+void AggExprEmitter::VisitVAArgExpr(VAArgExpr *VE) {
+ llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr());
+ llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType());
+
+ if (!ArgPtr) {
+ CGF.ErrorUnsupported(VE, "aggregate va_arg expression");
+ return;
+ }
+
+ EmitFinalDestCopy(VE, LValue::MakeAddr(ArgPtr, Qualifiers()));
+}
+
+void AggExprEmitter::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
+ llvm::Value *Val = DestPtr;
+
+ if (!Val) {
+ // Create a temporary variable.
+ Val = CGF.CreateMemTemp(E->getType(), "tmp");
+
+ // FIXME: volatile
+ CGF.EmitAggExpr(E->getSubExpr(), Val, false);
+ } else
+ Visit(E->getSubExpr());
+
+ // Don't make this a live temporary if we're emitting an initializer expr.
+ if (!IsInitializer)
+ CGF.PushCXXTemporary(E->getTemporary(), Val);
+}
+
+void
+AggExprEmitter::VisitCXXConstructExpr(const CXXConstructExpr *E) {
+ llvm::Value *Val = DestPtr;
+
+ if (!Val) {
+ // Create a temporary variable.
+ Val = CGF.CreateMemTemp(E->getType(), "tmp");
+ }
+
+ if (E->requiresZeroInitialization())
+ EmitNullInitializationToLValue(LValue::MakeAddr(Val,
+ // FIXME: Qualifiers()?
+ E->getType().getQualifiers()),
+ E->getType());
+
+ CGF.EmitCXXConstructExpr(Val, E);
+}
+
+void AggExprEmitter::VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) {
+ llvm::Value *Val = DestPtr;
+
+ if (!Val) {
+ // Create a temporary variable.
+ Val = CGF.CreateMemTemp(E->getType(), "tmp");
+ }
+ CGF.EmitCXXExprWithTemporaries(E, Val, VolatileDest, IsInitializer);
+}
+
+void AggExprEmitter::VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E) {
+ llvm::Value *Val = DestPtr;
+
+ if (!Val) {
+ // Create a temporary variable.
+ Val = CGF.CreateMemTemp(E->getType(), "tmp");
+ }
+ LValue LV = LValue::MakeAddr(Val, Qualifiers());
+ EmitNullInitializationToLValue(LV, E->getType());
+}
+
+void AggExprEmitter::VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
+ llvm::Value *Val = DestPtr;
+
+ if (!Val) {
+ // Create a temporary variable.
+ Val = CGF.CreateMemTemp(E->getType(), "tmp");
+ }
+ LValue LV = LValue::MakeAddr(Val, Qualifiers());
+ EmitNullInitializationToLValue(LV, E->getType());
+}
+
+void
+AggExprEmitter::EmitInitializationToLValue(Expr* E, LValue LV, QualType T) {
+ // FIXME: Ignore result?
+ // FIXME: Are initializers affected by volatile?
+ if (isa<ImplicitValueInitExpr>(E)) {
+ EmitNullInitializationToLValue(LV, T);
+ } else if (T->isReferenceType()) {
+ RValue RV = CGF.EmitReferenceBindingToExpr(E, /*IsInitializer=*/false);
+ CGF.EmitStoreThroughLValue(RV, LV, T);
+ } else if (T->isAnyComplexType()) {
+ CGF.EmitComplexExprIntoAddr(E, LV.getAddress(), false);
+ } else if (CGF.hasAggregateLLVMType(T)) {
+ CGF.EmitAnyExpr(E, LV.getAddress(), false);
+ } else {
+ CGF.EmitStoreThroughLValue(CGF.EmitAnyExpr(E), LV, T);
+ }
+}
+
+void AggExprEmitter::EmitNullInitializationToLValue(LValue LV, QualType T) {
+ if (!CGF.hasAggregateLLVMType(T)) {
+ // For non-aggregates, we can store zero
+ llvm::Value *Null = llvm::Constant::getNullValue(CGF.ConvertType(T));
+ CGF.EmitStoreThroughLValue(RValue::get(Null), LV, T);
+ } else {
+ // Otherwise, just memset the whole thing to zero. This is legal
+ // because in LLVM, all default initializers are guaranteed to have a
+ // bit pattern of all zeros.
+ // FIXME: That isn't true for member pointers!
+ // There's a potential optimization opportunity in combining
+ // memsets; that would be easy for arrays, but relatively
+ // difficult for structures with the current code.
+ CGF.EmitMemSetToZero(LV.getAddress(), T);
+ }
+}
+
+void AggExprEmitter::VisitInitListExpr(InitListExpr *E) {
+#if 0
+ // FIXME: Assess perf here? Figure out what cases are worth optimizing here
+ // (Length of globals? Chunks of zeroed-out space?).
+ //
+ // If we can, prefer a copy from a global; this is a lot less code for long
+ // globals, and it's easier for the current optimizers to analyze.
+ if (llvm::Constant* C = CGF.CGM.EmitConstantExpr(E, E->getType(), &CGF)) {
+ llvm::GlobalVariable* GV =
+ new llvm::GlobalVariable(CGF.CGM.getModule(), C->getType(), true,
+ llvm::GlobalValue::InternalLinkage, C, "");
+ EmitFinalDestCopy(E, LValue::MakeAddr(GV, Qualifiers()));
+ return;
+ }
+#endif
+ if (E->hadArrayRangeDesignator()) {
+ CGF.ErrorUnsupported(E, "GNU array range designator extension");
+ }
+
+ // Handle initialization of an array.
+ if (E->getType()->isArrayType()) {
+ const llvm::PointerType *APType =
+ cast<llvm::PointerType>(DestPtr->getType());
+ const llvm::ArrayType *AType =
+ cast<llvm::ArrayType>(APType->getElementType());
+
+ uint64_t NumInitElements = E->getNumInits();
+
+ if (E->getNumInits() > 0) {
+ QualType T1 = E->getType();
+ QualType T2 = E->getInit(0)->getType();
+ if (CGF.getContext().hasSameUnqualifiedType(T1, T2)) {
+ EmitAggLoadOfLValue(E->getInit(0));
+ return;
+ }
+ }
+
+ uint64_t NumArrayElements = AType->getNumElements();
+ QualType ElementType = CGF.getContext().getCanonicalType(E->getType());
+ ElementType = CGF.getContext().getAsArrayType(ElementType)->getElementType();
+
+ // FIXME: were we intentionally ignoring address spaces and GC attributes?
+ Qualifiers Quals = CGF.MakeQualifiers(ElementType);
+
+ for (uint64_t i = 0; i != NumArrayElements; ++i) {
+ llvm::Value *NextVal = Builder.CreateStructGEP(DestPtr, i, ".array");
+ if (i < NumInitElements)
+ EmitInitializationToLValue(E->getInit(i),
+ LValue::MakeAddr(NextVal, Quals),
+ ElementType);
+ else
+ EmitNullInitializationToLValue(LValue::MakeAddr(NextVal, Quals),
+ ElementType);
+ }
+ return;
+ }
+
+ assert(E->getType()->isRecordType() && "Only support structs/unions here!");
+
+ // Do struct initialization; this code just sets each individual member
+ // to the approprate value. This makes bitfield support automatic;
+ // the disadvantage is that the generated code is more difficult for
+ // the optimizer, especially with bitfields.
+ unsigned NumInitElements = E->getNumInits();
+ RecordDecl *SD = E->getType()->getAs<RecordType>()->getDecl();
+ unsigned CurInitVal = 0;
+
+ if (E->getType()->isUnionType()) {
+ // Only initialize one field of a union. The field itself is
+ // specified by the initializer list.
+ if (!E->getInitializedFieldInUnion()) {
+ // Empty union; we have nothing to do.
+
+#ifndef NDEBUG
+ // Make sure that it's really an empty and not a failure of
+ // semantic analysis.
+ for (RecordDecl::field_iterator Field = SD->field_begin(),
+ FieldEnd = SD->field_end();
+ Field != FieldEnd; ++Field)
+ assert(Field->isUnnamedBitfield() && "Only unnamed bitfields allowed");
+#endif
+ return;
+ }
+
+ // FIXME: volatility
+ FieldDecl *Field = E->getInitializedFieldInUnion();
+ LValue FieldLoc = CGF.EmitLValueForFieldInitialization(DestPtr, Field, 0);
+
+ if (NumInitElements) {
+ // Store the initializer into the field
+ EmitInitializationToLValue(E->getInit(0), FieldLoc, Field->getType());
+ } else {
+ // Default-initialize to null
+ EmitNullInitializationToLValue(FieldLoc, Field->getType());
+ }
+
+ return;
+ }
+
+ // Here we iterate over the fields; this makes it simpler to both
+ // default-initialize fields and skip over unnamed fields.
+ for (RecordDecl::field_iterator Field = SD->field_begin(),
+ FieldEnd = SD->field_end();
+ Field != FieldEnd; ++Field) {
+ // We're done once we hit the flexible array member
+ if (Field->getType()->isIncompleteArrayType())
+ break;
+
+ if (Field->isUnnamedBitfield())
+ continue;
+
+ // FIXME: volatility
+ LValue FieldLoc = CGF.EmitLValueForFieldInitialization(DestPtr, *Field, 0);
+ // We never generate write-barries for initialized fields.
+ LValue::SetObjCNonGC(FieldLoc, true);
+ if (CurInitVal < NumInitElements) {
+ // Store the initializer into the field
+ EmitInitializationToLValue(E->getInit(CurInitVal++), FieldLoc,
+ Field->getType());
+ } else {
+ // We're out of initalizers; default-initialize to null
+ EmitNullInitializationToLValue(FieldLoc, Field->getType());
+ }
+ }
+}
+
+//===----------------------------------------------------------------------===//
+// Entry Points into this File
+//===----------------------------------------------------------------------===//
+
+/// EmitAggExpr - Emit the computation of the specified expression of aggregate
+/// type. The result is computed into DestPtr. Note that if DestPtr is null,
+/// the value of the aggregate expression is not needed. If VolatileDest is
+/// true, DestPtr cannot be 0.
+//
+// FIXME: Take Qualifiers object.
+void CodeGenFunction::EmitAggExpr(const Expr *E, llvm::Value *DestPtr,
+ bool VolatileDest, bool IgnoreResult,
+ bool IsInitializer,
+ bool RequiresGCollection) {
+ assert(E && hasAggregateLLVMType(E->getType()) &&
+ "Invalid aggregate expression to emit");
+ assert ((DestPtr != 0 || VolatileDest == false)
+ && "volatile aggregate can't be 0");
+
+ AggExprEmitter(*this, DestPtr, VolatileDest, IgnoreResult, IsInitializer,
+ RequiresGCollection)
+ .Visit(const_cast<Expr*>(E));
+}
+
+LValue CodeGenFunction::EmitAggExprToLValue(const Expr *E) {
+ assert(hasAggregateLLVMType(E->getType()) && "Invalid argument!");
+ Qualifiers Q = MakeQualifiers(E->getType());
+ llvm::Value *Temp = CreateMemTemp(E->getType());
+ EmitAggExpr(E, Temp, Q.hasVolatile());
+ return LValue::MakeAddr(Temp, Q);
+}
+
+void CodeGenFunction::EmitAggregateClear(llvm::Value *DestPtr, QualType Ty) {
+ assert(!Ty->isAnyComplexType() && "Shouldn't happen for complex");
+
+ EmitMemSetToZero(DestPtr, Ty);
+}
+
+void CodeGenFunction::EmitAggregateCopy(llvm::Value *DestPtr,
+ llvm::Value *SrcPtr, QualType Ty,
+ bool isVolatile) {
+ assert(!Ty->isAnyComplexType() && "Shouldn't happen for complex");
+
+ // Aggregate assignment turns into llvm.memcpy. This is almost valid per
+ // C99 6.5.16.1p3, which states "If the value being stored in an object is
+ // read from another object that overlaps in anyway the storage of the first
+ // object, then the overlap shall be exact and the two objects shall have
+ // qualified or unqualified versions of a compatible type."
+ //
+ // memcpy is not defined if the source and destination pointers are exactly
+ // equal, but other compilers do this optimization, and almost every memcpy
+ // implementation handles this case safely. If there is a libc that does not
+ // safely handle this, we can add a target hook.
+ const llvm::Type *BP = llvm::Type::getInt8PtrTy(VMContext);
+ if (DestPtr->getType() != BP)
+ DestPtr = Builder.CreateBitCast(DestPtr, BP, "tmp");
+ if (SrcPtr->getType() != BP)
+ SrcPtr = Builder.CreateBitCast(SrcPtr, BP, "tmp");
+
+ // Get size and alignment info for this aggregate.
+ std::pair<uint64_t, unsigned> TypeInfo = getContext().getTypeInfo(Ty);
+
+ // FIXME: Handle variable sized types.
+ const llvm::Type *IntPtr =
+ llvm::IntegerType::get(VMContext, LLVMPointerWidth);
+
+ // FIXME: If we have a volatile struct, the optimizer can remove what might
+ // appear to be `extra' memory ops:
+ //
+ // volatile struct { int i; } a, b;
+ //
+ // int main() {
+ // a = b;
+ // a = b;
+ // }
+ //
+ // we need to use a differnt call here. We use isVolatile to indicate when
+ // either the source or the destination is volatile.
+ Builder.CreateCall4(CGM.getMemCpyFn(),
+ DestPtr, SrcPtr,
+ // TypeInfo.first describes size in bits.
+ llvm::ConstantInt::get(IntPtr, TypeInfo.first/8),
+ llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
+ TypeInfo.second/8));
+}