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2169 lines
81 KiB
2169 lines
81 KiB
//===--- CGExprAgg.cpp - Emit LLVM Code from Aggregate Expressions --------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This contains code to emit Aggregate Expr nodes as LLVM code.
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//
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//===----------------------------------------------------------------------===//
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#include "CGCXXABI.h"
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#include "CGObjCRuntime.h"
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#include "CodeGenFunction.h"
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#include "CodeGenModule.h"
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#include "ConstantEmitter.h"
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#include "TargetInfo.h"
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#include "clang/AST/ASTContext.h"
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#include "clang/AST/Attr.h"
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#include "clang/AST/DeclCXX.h"
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#include "clang/AST/DeclTemplate.h"
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#include "clang/AST/StmtVisitor.h"
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#include "llvm/IR/Constants.h"
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#include "llvm/IR/Function.h"
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#include "llvm/IR/GlobalVariable.h"
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#include "llvm/IR/IntrinsicInst.h"
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#include "llvm/IR/Intrinsics.h"
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using namespace clang;
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using namespace CodeGen;
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//===----------------------------------------------------------------------===//
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// Aggregate Expression Emitter
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//===----------------------------------------------------------------------===//
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namespace {
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class AggExprEmitter : public StmtVisitor<AggExprEmitter> {
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CodeGenFunction &CGF;
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CGBuilderTy &Builder;
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AggValueSlot Dest;
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bool IsResultUnused;
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AggValueSlot EnsureSlot(QualType T) {
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if (!Dest.isIgnored()) return Dest;
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return CGF.CreateAggTemp(T, "agg.tmp.ensured");
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}
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void EnsureDest(QualType T) {
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if (!Dest.isIgnored()) return;
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Dest = CGF.CreateAggTemp(T, "agg.tmp.ensured");
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}
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// Calls `Fn` with a valid return value slot, potentially creating a temporary
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// to do so. If a temporary is created, an appropriate copy into `Dest` will
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// be emitted, as will lifetime markers.
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//
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// The given function should take a ReturnValueSlot, and return an RValue that
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// points to said slot.
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void withReturnValueSlot(const Expr *E,
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llvm::function_ref<RValue(ReturnValueSlot)> Fn);
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public:
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AggExprEmitter(CodeGenFunction &cgf, AggValueSlot Dest, bool IsResultUnused)
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: CGF(cgf), Builder(CGF.Builder), Dest(Dest),
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IsResultUnused(IsResultUnused) { }
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//===--------------------------------------------------------------------===//
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// Utilities
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//===--------------------------------------------------------------------===//
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/// EmitAggLoadOfLValue - Given an expression with aggregate type that
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/// represents a value lvalue, this method emits the address of the lvalue,
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/// then loads the result into DestPtr.
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void EmitAggLoadOfLValue(const Expr *E);
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enum ExprValueKind {
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EVK_RValue,
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EVK_NonRValue
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};
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/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired.
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/// SrcIsRValue is true if source comes from an RValue.
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void EmitFinalDestCopy(QualType type, const LValue &src,
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ExprValueKind SrcValueKind = EVK_NonRValue);
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void EmitFinalDestCopy(QualType type, RValue src);
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void EmitCopy(QualType type, const AggValueSlot &dest,
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const AggValueSlot &src);
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void EmitMoveFromReturnSlot(const Expr *E, RValue Src);
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void EmitArrayInit(Address DestPtr, llvm::ArrayType *AType,
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QualType ArrayQTy, InitListExpr *E);
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AggValueSlot::NeedsGCBarriers_t needsGC(QualType T) {
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if (CGF.getLangOpts().getGC() && TypeRequiresGCollection(T))
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return AggValueSlot::NeedsGCBarriers;
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return AggValueSlot::DoesNotNeedGCBarriers;
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}
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bool TypeRequiresGCollection(QualType T);
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//===--------------------------------------------------------------------===//
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// Visitor Methods
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//===--------------------------------------------------------------------===//
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void Visit(Expr *E) {
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ApplyDebugLocation DL(CGF, E);
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StmtVisitor<AggExprEmitter>::Visit(E);
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}
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void VisitStmt(Stmt *S) {
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CGF.ErrorUnsupported(S, "aggregate expression");
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}
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void VisitParenExpr(ParenExpr *PE) { Visit(PE->getSubExpr()); }
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void VisitGenericSelectionExpr(GenericSelectionExpr *GE) {
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Visit(GE->getResultExpr());
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}
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void VisitCoawaitExpr(CoawaitExpr *E) {
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CGF.EmitCoawaitExpr(*E, Dest, IsResultUnused);
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}
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void VisitCoyieldExpr(CoyieldExpr *E) {
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CGF.EmitCoyieldExpr(*E, Dest, IsResultUnused);
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}
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void VisitUnaryCoawait(UnaryOperator *E) { Visit(E->getSubExpr()); }
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void VisitUnaryExtension(UnaryOperator *E) { Visit(E->getSubExpr()); }
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void VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *E) {
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return Visit(E->getReplacement());
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}
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void VisitConstantExpr(ConstantExpr *E) {
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if (llvm::Value *Result = ConstantEmitter(CGF).tryEmitConstantExpr(E)) {
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CGF.EmitAggregateStore(Result, Dest.getAddress(),
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E->getType().isVolatileQualified());
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return;
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}
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return Visit(E->getSubExpr());
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}
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// l-values.
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void VisitDeclRefExpr(DeclRefExpr *E) { EmitAggLoadOfLValue(E); }
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void VisitMemberExpr(MemberExpr *ME) { EmitAggLoadOfLValue(ME); }
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void VisitUnaryDeref(UnaryOperator *E) { EmitAggLoadOfLValue(E); }
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void VisitStringLiteral(StringLiteral *E) { EmitAggLoadOfLValue(E); }
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void VisitCompoundLiteralExpr(CompoundLiteralExpr *E);
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void VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
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EmitAggLoadOfLValue(E);
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}
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void VisitPredefinedExpr(const PredefinedExpr *E) {
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EmitAggLoadOfLValue(E);
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}
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// Operators.
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void VisitCastExpr(CastExpr *E);
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void VisitCallExpr(const CallExpr *E);
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void VisitStmtExpr(const StmtExpr *E);
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void VisitBinaryOperator(const BinaryOperator *BO);
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void VisitPointerToDataMemberBinaryOperator(const BinaryOperator *BO);
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void VisitBinAssign(const BinaryOperator *E);
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void VisitBinComma(const BinaryOperator *E);
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void VisitBinCmp(const BinaryOperator *E);
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void VisitCXXRewrittenBinaryOperator(CXXRewrittenBinaryOperator *E) {
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Visit(E->getSemanticForm());
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}
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void VisitObjCMessageExpr(ObjCMessageExpr *E);
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void VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
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EmitAggLoadOfLValue(E);
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}
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void VisitDesignatedInitUpdateExpr(DesignatedInitUpdateExpr *E);
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void VisitAbstractConditionalOperator(const AbstractConditionalOperator *CO);
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void VisitChooseExpr(const ChooseExpr *CE);
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void VisitInitListExpr(InitListExpr *E);
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void VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E,
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llvm::Value *outerBegin = nullptr);
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void VisitImplicitValueInitExpr(ImplicitValueInitExpr *E);
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void VisitNoInitExpr(NoInitExpr *E) { } // Do nothing.
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void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
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CodeGenFunction::CXXDefaultArgExprScope Scope(CGF, DAE);
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Visit(DAE->getExpr());
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}
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void VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) {
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CodeGenFunction::CXXDefaultInitExprScope Scope(CGF, DIE);
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Visit(DIE->getExpr());
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}
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void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E);
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void VisitCXXConstructExpr(const CXXConstructExpr *E);
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void VisitCXXInheritedCtorInitExpr(const CXXInheritedCtorInitExpr *E);
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void VisitLambdaExpr(LambdaExpr *E);
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void VisitCXXStdInitializerListExpr(CXXStdInitializerListExpr *E);
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void VisitExprWithCleanups(ExprWithCleanups *E);
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void VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E);
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void VisitCXXTypeidExpr(CXXTypeidExpr *E) { EmitAggLoadOfLValue(E); }
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void VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E);
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void VisitOpaqueValueExpr(OpaqueValueExpr *E);
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void VisitPseudoObjectExpr(PseudoObjectExpr *E) {
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if (E->isGLValue()) {
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LValue LV = CGF.EmitPseudoObjectLValue(E);
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return EmitFinalDestCopy(E->getType(), LV);
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}
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CGF.EmitPseudoObjectRValue(E, EnsureSlot(E->getType()));
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}
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void VisitVAArgExpr(VAArgExpr *E);
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void EmitInitializationToLValue(Expr *E, LValue Address);
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void EmitNullInitializationToLValue(LValue Address);
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// case Expr::ChooseExprClass:
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void VisitCXXThrowExpr(const CXXThrowExpr *E) { CGF.EmitCXXThrowExpr(E); }
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void VisitAtomicExpr(AtomicExpr *E) {
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RValue Res = CGF.EmitAtomicExpr(E);
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EmitFinalDestCopy(E->getType(), Res);
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}
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};
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} // end anonymous namespace.
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//===----------------------------------------------------------------------===//
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// Utilities
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//===----------------------------------------------------------------------===//
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/// EmitAggLoadOfLValue - Given an expression with aggregate type that
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/// represents a value lvalue, this method emits the address of the lvalue,
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/// then loads the result into DestPtr.
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void AggExprEmitter::EmitAggLoadOfLValue(const Expr *E) {
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LValue LV = CGF.EmitLValue(E);
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// If the type of the l-value is atomic, then do an atomic load.
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if (LV.getType()->isAtomicType() || CGF.LValueIsSuitableForInlineAtomic(LV)) {
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CGF.EmitAtomicLoad(LV, E->getExprLoc(), Dest);
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return;
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}
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EmitFinalDestCopy(E->getType(), LV);
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}
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/// True if the given aggregate type requires special GC API calls.
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bool AggExprEmitter::TypeRequiresGCollection(QualType T) {
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// Only record types have members that might require garbage collection.
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const RecordType *RecordTy = T->getAs<RecordType>();
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if (!RecordTy) return false;
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// Don't mess with non-trivial C++ types.
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RecordDecl *Record = RecordTy->getDecl();
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if (isa<CXXRecordDecl>(Record) &&
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(cast<CXXRecordDecl>(Record)->hasNonTrivialCopyConstructor() ||
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!cast<CXXRecordDecl>(Record)->hasTrivialDestructor()))
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return false;
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// Check whether the type has an object member.
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return Record->hasObjectMember();
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}
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void AggExprEmitter::withReturnValueSlot(
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const Expr *E, llvm::function_ref<RValue(ReturnValueSlot)> EmitCall) {
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QualType RetTy = E->getType();
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bool RequiresDestruction =
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!Dest.isExternallyDestructed() &&
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RetTy.isDestructedType() == QualType::DK_nontrivial_c_struct;
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// If it makes no observable difference, save a memcpy + temporary.
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//
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// We need to always provide our own temporary if destruction is required.
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// Otherwise, EmitCall will emit its own, notice that it's "unused", and end
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// its lifetime before we have the chance to emit a proper destructor call.
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bool UseTemp = Dest.isPotentiallyAliased() || Dest.requiresGCollection() ||
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(RequiresDestruction && !Dest.getAddress().isValid());
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Address RetAddr = Address::invalid();
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Address RetAllocaAddr = Address::invalid();
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EHScopeStack::stable_iterator LifetimeEndBlock;
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llvm::Value *LifetimeSizePtr = nullptr;
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llvm::IntrinsicInst *LifetimeStartInst = nullptr;
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if (!UseTemp) {
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RetAddr = Dest.getAddress();
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} else {
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RetAddr = CGF.CreateMemTemp(RetTy, "tmp", &RetAllocaAddr);
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uint64_t Size =
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CGF.CGM.getDataLayout().getTypeAllocSize(CGF.ConvertTypeForMem(RetTy));
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LifetimeSizePtr = CGF.EmitLifetimeStart(Size, RetAllocaAddr.getPointer());
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if (LifetimeSizePtr) {
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LifetimeStartInst =
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cast<llvm::IntrinsicInst>(std::prev(Builder.GetInsertPoint()));
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assert(LifetimeStartInst->getIntrinsicID() ==
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llvm::Intrinsic::lifetime_start &&
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"Last insertion wasn't a lifetime.start?");
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CGF.pushFullExprCleanup<CodeGenFunction::CallLifetimeEnd>(
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NormalEHLifetimeMarker, RetAllocaAddr, LifetimeSizePtr);
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LifetimeEndBlock = CGF.EHStack.stable_begin();
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}
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}
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RValue Src =
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EmitCall(ReturnValueSlot(RetAddr, Dest.isVolatile(), IsResultUnused,
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Dest.isExternallyDestructed()));
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if (!UseTemp)
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return;
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assert(Dest.getPointer() != Src.getAggregatePointer());
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EmitFinalDestCopy(E->getType(), Src);
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if (!RequiresDestruction && LifetimeStartInst) {
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// If there's no dtor to run, the copy was the last use of our temporary.
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// Since we're not guaranteed to be in an ExprWithCleanups, clean up
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// eagerly.
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CGF.DeactivateCleanupBlock(LifetimeEndBlock, LifetimeStartInst);
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CGF.EmitLifetimeEnd(LifetimeSizePtr, RetAllocaAddr.getPointer());
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}
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}
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/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired.
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void AggExprEmitter::EmitFinalDestCopy(QualType type, RValue src) {
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assert(src.isAggregate() && "value must be aggregate value!");
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LValue srcLV = CGF.MakeAddrLValue(src.getAggregateAddress(), type);
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EmitFinalDestCopy(type, srcLV, EVK_RValue);
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}
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/// EmitFinalDestCopy - Perform the final copy to DestPtr, if desired.
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void AggExprEmitter::EmitFinalDestCopy(QualType type, const LValue &src,
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ExprValueKind SrcValueKind) {
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// If Dest is ignored, then we're evaluating an aggregate expression
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// in a context that doesn't care about the result. Note that loads
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// from volatile l-values force the existence of a non-ignored
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// destination.
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if (Dest.isIgnored())
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return;
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// Copy non-trivial C structs here.
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LValue DstLV = CGF.MakeAddrLValue(
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Dest.getAddress(), Dest.isVolatile() ? type.withVolatile() : type);
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if (SrcValueKind == EVK_RValue) {
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if (type.isNonTrivialToPrimitiveDestructiveMove() == QualType::PCK_Struct) {
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if (Dest.isPotentiallyAliased())
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CGF.callCStructMoveAssignmentOperator(DstLV, src);
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else
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CGF.callCStructMoveConstructor(DstLV, src);
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return;
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}
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} else {
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if (type.isNonTrivialToPrimitiveCopy() == QualType::PCK_Struct) {
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if (Dest.isPotentiallyAliased())
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CGF.callCStructCopyAssignmentOperator(DstLV, src);
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else
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CGF.callCStructCopyConstructor(DstLV, src);
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return;
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}
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}
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AggValueSlot srcAgg = AggValueSlot::forLValue(
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src, CGF, AggValueSlot::IsDestructed, needsGC(type),
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AggValueSlot::IsAliased, AggValueSlot::MayOverlap);
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EmitCopy(type, Dest, srcAgg);
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}
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/// Perform a copy from the source into the destination.
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///
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/// \param type - the type of the aggregate being copied; qualifiers are
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/// ignored
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void AggExprEmitter::EmitCopy(QualType type, const AggValueSlot &dest,
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const AggValueSlot &src) {
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if (dest.requiresGCollection()) {
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CharUnits sz = dest.getPreferredSize(CGF.getContext(), type);
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llvm::Value *size = llvm::ConstantInt::get(CGF.SizeTy, sz.getQuantity());
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CGF.CGM.getObjCRuntime().EmitGCMemmoveCollectable(CGF,
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dest.getAddress(),
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src.getAddress(),
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size);
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return;
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}
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// If the result of the assignment is used, copy the LHS there also.
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// It's volatile if either side is. Use the minimum alignment of
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// the two sides.
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LValue DestLV = CGF.MakeAddrLValue(dest.getAddress(), type);
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LValue SrcLV = CGF.MakeAddrLValue(src.getAddress(), type);
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CGF.EmitAggregateCopy(DestLV, SrcLV, type, dest.mayOverlap(),
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dest.isVolatile() || src.isVolatile());
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}
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/// Emit the initializer for a std::initializer_list initialized with a
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/// real initializer list.
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void
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AggExprEmitter::VisitCXXStdInitializerListExpr(CXXStdInitializerListExpr *E) {
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// Emit an array containing the elements. The array is externally destructed
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// if the std::initializer_list object is.
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ASTContext &Ctx = CGF.getContext();
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LValue Array = CGF.EmitLValue(E->getSubExpr());
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assert(Array.isSimple() && "initializer_list array not a simple lvalue");
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Address ArrayPtr = Array.getAddress(CGF);
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const ConstantArrayType *ArrayType =
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Ctx.getAsConstantArrayType(E->getSubExpr()->getType());
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assert(ArrayType && "std::initializer_list constructed from non-array");
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// FIXME: Perform the checks on the field types in SemaInit.
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RecordDecl *Record = E->getType()->castAs<RecordType>()->getDecl();
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RecordDecl::field_iterator Field = Record->field_begin();
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if (Field == Record->field_end()) {
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CGF.ErrorUnsupported(E, "weird std::initializer_list");
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return;
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}
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// Start pointer.
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if (!Field->getType()->isPointerType() ||
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!Ctx.hasSameType(Field->getType()->getPointeeType(),
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ArrayType->getElementType())) {
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CGF.ErrorUnsupported(E, "weird std::initializer_list");
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return;
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}
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AggValueSlot Dest = EnsureSlot(E->getType());
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LValue DestLV = CGF.MakeAddrLValue(Dest.getAddress(), E->getType());
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LValue Start = CGF.EmitLValueForFieldInitialization(DestLV, *Field);
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llvm::Value *Zero = llvm::ConstantInt::get(CGF.PtrDiffTy, 0);
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llvm::Value *IdxStart[] = { Zero, Zero };
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llvm::Value *ArrayStart =
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Builder.CreateInBoundsGEP(ArrayPtr.getPointer(), IdxStart, "arraystart");
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CGF.EmitStoreThroughLValue(RValue::get(ArrayStart), Start);
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++Field;
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if (Field == Record->field_end()) {
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CGF.ErrorUnsupported(E, "weird std::initializer_list");
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return;
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}
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llvm::Value *Size = Builder.getInt(ArrayType->getSize());
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LValue EndOrLength = CGF.EmitLValueForFieldInitialization(DestLV, *Field);
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if (Field->getType()->isPointerType() &&
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Ctx.hasSameType(Field->getType()->getPointeeType(),
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ArrayType->getElementType())) {
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// End pointer.
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llvm::Value *IdxEnd[] = { Zero, Size };
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llvm::Value *ArrayEnd =
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Builder.CreateInBoundsGEP(ArrayPtr.getPointer(), IdxEnd, "arrayend");
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CGF.EmitStoreThroughLValue(RValue::get(ArrayEnd), EndOrLength);
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} else if (Ctx.hasSameType(Field->getType(), Ctx.getSizeType())) {
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// Length.
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CGF.EmitStoreThroughLValue(RValue::get(Size), EndOrLength);
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} else {
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CGF.ErrorUnsupported(E, "weird std::initializer_list");
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return;
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}
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}
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/// Determine if E is a trivial array filler, that is, one that is
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/// equivalent to zero-initialization.
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static bool isTrivialFiller(Expr *E) {
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|
if (!E)
|
|
return true;
|
|
|
|
if (isa<ImplicitValueInitExpr>(E))
|
|
return true;
|
|
|
|
if (auto *ILE = dyn_cast<InitListExpr>(E)) {
|
|
if (ILE->getNumInits())
|
|
return false;
|
|
return isTrivialFiller(ILE->getArrayFiller());
|
|
}
|
|
|
|
if (auto *Cons = dyn_cast_or_null<CXXConstructExpr>(E))
|
|
return Cons->getConstructor()->isDefaultConstructor() &&
|
|
Cons->getConstructor()->isTrivial();
|
|
|
|
// FIXME: Are there other cases where we can avoid emitting an initializer?
|
|
return false;
|
|
}
|
|
|
|
/// Emit initialization of an array from an initializer list.
|
|
void AggExprEmitter::EmitArrayInit(Address DestPtr, llvm::ArrayType *AType,
|
|
QualType ArrayQTy, InitListExpr *E) {
|
|
uint64_t NumInitElements = E->getNumInits();
|
|
|
|
uint64_t NumArrayElements = AType->getNumElements();
|
|
assert(NumInitElements <= NumArrayElements);
|
|
|
|
QualType elementType =
|
|
CGF.getContext().getAsArrayType(ArrayQTy)->getElementType();
|
|
|
|
// DestPtr is an array*. Construct an elementType* by drilling
|
|
// down a level.
|
|
llvm::Value *zero = llvm::ConstantInt::get(CGF.SizeTy, 0);
|
|
llvm::Value *indices[] = { zero, zero };
|
|
llvm::Value *begin =
|
|
Builder.CreateInBoundsGEP(DestPtr.getPointer(), indices, "arrayinit.begin");
|
|
|
|
CharUnits elementSize = CGF.getContext().getTypeSizeInChars(elementType);
|
|
CharUnits elementAlign =
|
|
DestPtr.getAlignment().alignmentOfArrayElement(elementSize);
|
|
|
|
// Consider initializing the array by copying from a global. For this to be
|
|
// more efficient than per-element initialization, the size of the elements
|
|
// with explicit initializers should be large enough.
|
|
if (NumInitElements * elementSize.getQuantity() > 16 &&
|
|
elementType.isTriviallyCopyableType(CGF.getContext())) {
|
|
CodeGen::CodeGenModule &CGM = CGF.CGM;
|
|
ConstantEmitter Emitter(CGF);
|
|
LangAS AS = ArrayQTy.getAddressSpace();
|
|
if (llvm::Constant *C = Emitter.tryEmitForInitializer(E, AS, ArrayQTy)) {
|
|
auto GV = new llvm::GlobalVariable(
|
|
CGM.getModule(), C->getType(),
|
|
CGM.isTypeConstant(ArrayQTy, /* ExcludeCtorDtor= */ true),
|
|
llvm::GlobalValue::PrivateLinkage, C, "constinit",
|
|
/* InsertBefore= */ nullptr, llvm::GlobalVariable::NotThreadLocal,
|
|
CGM.getContext().getTargetAddressSpace(AS));
|
|
Emitter.finalize(GV);
|
|
CharUnits Align = CGM.getContext().getTypeAlignInChars(ArrayQTy);
|
|
GV->setAlignment(Align.getAsAlign());
|
|
EmitFinalDestCopy(ArrayQTy, CGF.MakeAddrLValue(GV, ArrayQTy, Align));
|
|
return;
|
|
}
|
|
}
|
|
|
|
// Exception safety requires us to destroy all the
|
|
// already-constructed members if an initializer throws.
|
|
// For that, we'll need an EH cleanup.
|
|
QualType::DestructionKind dtorKind = elementType.isDestructedType();
|
|
Address endOfInit = Address::invalid();
|
|
EHScopeStack::stable_iterator cleanup;
|
|
llvm::Instruction *cleanupDominator = nullptr;
|
|
if (CGF.needsEHCleanup(dtorKind)) {
|
|
// In principle we could tell the cleanup where we are more
|
|
// directly, but the control flow can get so varied here that it
|
|
// would actually be quite complex. Therefore we go through an
|
|
// alloca.
|
|
endOfInit = CGF.CreateTempAlloca(begin->getType(), CGF.getPointerAlign(),
|
|
"arrayinit.endOfInit");
|
|
cleanupDominator = Builder.CreateStore(begin, endOfInit);
|
|
CGF.pushIrregularPartialArrayCleanup(begin, endOfInit, elementType,
|
|
elementAlign,
|
|
CGF.getDestroyer(dtorKind));
|
|
cleanup = CGF.EHStack.stable_begin();
|
|
|
|
// Otherwise, remember that we didn't need a cleanup.
|
|
} else {
|
|
dtorKind = QualType::DK_none;
|
|
}
|
|
|
|
llvm::Value *one = llvm::ConstantInt::get(CGF.SizeTy, 1);
|
|
|
|
// The 'current element to initialize'. The invariants on this
|
|
// variable are complicated. Essentially, after each iteration of
|
|
// the loop, it points to the last initialized element, except
|
|
// that it points to the beginning of the array before any
|
|
// elements have been initialized.
|
|
llvm::Value *element = begin;
|
|
|
|
// Emit the explicit initializers.
|
|
for (uint64_t i = 0; i != NumInitElements; ++i) {
|
|
// Advance to the next element.
|
|
if (i > 0) {
|
|
element = Builder.CreateInBoundsGEP(element, one, "arrayinit.element");
|
|
|
|
// Tell the cleanup that it needs to destroy up to this
|
|
// element. TODO: some of these stores can be trivially
|
|
// observed to be unnecessary.
|
|
if (endOfInit.isValid()) Builder.CreateStore(element, endOfInit);
|
|
}
|
|
|
|
LValue elementLV =
|
|
CGF.MakeAddrLValue(Address(element, elementAlign), elementType);
|
|
EmitInitializationToLValue(E->getInit(i), elementLV);
|
|
}
|
|
|
|
// Check whether there's a non-trivial array-fill expression.
|
|
Expr *filler = E->getArrayFiller();
|
|
bool hasTrivialFiller = isTrivialFiller(filler);
|
|
|
|
// Any remaining elements need to be zero-initialized, possibly
|
|
// using the filler expression. We can skip this if the we're
|
|
// emitting to zeroed memory.
|
|
if (NumInitElements != NumArrayElements &&
|
|
!(Dest.isZeroed() && hasTrivialFiller &&
|
|
CGF.getTypes().isZeroInitializable(elementType))) {
|
|
|
|
// Use an actual loop. This is basically
|
|
// do { *array++ = filler; } while (array != end);
|
|
|
|
// Advance to the start of the rest of the array.
|
|
if (NumInitElements) {
|
|
element = Builder.CreateInBoundsGEP(element, one, "arrayinit.start");
|
|
if (endOfInit.isValid()) Builder.CreateStore(element, endOfInit);
|
|
}
|
|
|
|
// Compute the end of the array.
|
|
llvm::Value *end = Builder.CreateInBoundsGEP(begin,
|
|
llvm::ConstantInt::get(CGF.SizeTy, NumArrayElements),
|
|
"arrayinit.end");
|
|
|
|
llvm::BasicBlock *entryBB = Builder.GetInsertBlock();
|
|
llvm::BasicBlock *bodyBB = CGF.createBasicBlock("arrayinit.body");
|
|
|
|
// Jump into the body.
|
|
CGF.EmitBlock(bodyBB);
|
|
llvm::PHINode *currentElement =
|
|
Builder.CreatePHI(element->getType(), 2, "arrayinit.cur");
|
|
currentElement->addIncoming(element, entryBB);
|
|
|
|
// Emit the actual filler expression.
|
|
{
|
|
// C++1z [class.temporary]p5:
|
|
// when a default constructor is called to initialize an element of
|
|
// an array with no corresponding initializer [...] the destruction of
|
|
// every temporary created in a default argument is sequenced before
|
|
// the construction of the next array element, if any
|
|
CodeGenFunction::RunCleanupsScope CleanupsScope(CGF);
|
|
LValue elementLV =
|
|
CGF.MakeAddrLValue(Address(currentElement, elementAlign), elementType);
|
|
if (filler)
|
|
EmitInitializationToLValue(filler, elementLV);
|
|
else
|
|
EmitNullInitializationToLValue(elementLV);
|
|
}
|
|
|
|
// Move on to the next element.
|
|
llvm::Value *nextElement =
|
|
Builder.CreateInBoundsGEP(currentElement, one, "arrayinit.next");
|
|
|
|
// Tell the EH cleanup that we finished with the last element.
|
|
if (endOfInit.isValid()) Builder.CreateStore(nextElement, endOfInit);
|
|
|
|
// Leave the loop if we're done.
|
|
llvm::Value *done = Builder.CreateICmpEQ(nextElement, end,
|
|
"arrayinit.done");
|
|
llvm::BasicBlock *endBB = CGF.createBasicBlock("arrayinit.end");
|
|
Builder.CreateCondBr(done, endBB, bodyBB);
|
|
currentElement->addIncoming(nextElement, Builder.GetInsertBlock());
|
|
|
|
CGF.EmitBlock(endBB);
|
|
}
|
|
|
|
// Leave the partial-array cleanup if we entered one.
|
|
if (dtorKind) CGF.DeactivateCleanupBlock(cleanup, cleanupDominator);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Visitor Methods
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
void AggExprEmitter::VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E){
|
|
Visit(E->getSubExpr());
|
|
}
|
|
|
|
void AggExprEmitter::VisitOpaqueValueExpr(OpaqueValueExpr *e) {
|
|
// If this is a unique OVE, just visit its source expression.
|
|
if (e->isUnique())
|
|
Visit(e->getSourceExpr());
|
|
else
|
|
EmitFinalDestCopy(e->getType(), CGF.getOrCreateOpaqueLValueMapping(e));
|
|
}
|
|
|
|
void
|
|
AggExprEmitter::VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
|
|
if (Dest.isPotentiallyAliased() &&
|
|
E->getType().isPODType(CGF.getContext())) {
|
|
// For a POD type, just emit a load of the lvalue + a copy, because our
|
|
// compound literal might alias the destination.
|
|
EmitAggLoadOfLValue(E);
|
|
return;
|
|
}
|
|
|
|
AggValueSlot Slot = EnsureSlot(E->getType());
|
|
|
|
// Block-scope compound literals are destroyed at the end of the enclosing
|
|
// scope in C.
|
|
bool Destruct =
|
|
!CGF.getLangOpts().CPlusPlus && !Slot.isExternallyDestructed();
|
|
if (Destruct)
|
|
Slot.setExternallyDestructed();
|
|
|
|
CGF.EmitAggExpr(E->getInitializer(), Slot);
|
|
|
|
if (Destruct)
|
|
if (QualType::DestructionKind DtorKind = E->getType().isDestructedType())
|
|
CGF.pushLifetimeExtendedDestroy(
|
|
CGF.getCleanupKind(DtorKind), Slot.getAddress(), E->getType(),
|
|
CGF.getDestroyer(DtorKind), DtorKind & EHCleanup);
|
|
}
|
|
|
|
/// Attempt to look through various unimportant expressions to find a
|
|
/// cast of the given kind.
|
|
static Expr *findPeephole(Expr *op, CastKind kind, const ASTContext &ctx) {
|
|
op = op->IgnoreParenNoopCasts(ctx);
|
|
if (auto castE = dyn_cast<CastExpr>(op)) {
|
|
if (castE->getCastKind() == kind)
|
|
return castE->getSubExpr();
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
void AggExprEmitter::VisitCastExpr(CastExpr *E) {
|
|
if (const auto *ECE = dyn_cast<ExplicitCastExpr>(E))
|
|
CGF.CGM.EmitExplicitCastExprType(ECE, &CGF);
|
|
switch (E->getCastKind()) {
|
|
case CK_Dynamic: {
|
|
// FIXME: Can this actually happen? We have no test coverage for it.
|
|
assert(isa<CXXDynamicCastExpr>(E) && "CK_Dynamic without a dynamic_cast?");
|
|
LValue LV = CGF.EmitCheckedLValue(E->getSubExpr(),
|
|
CodeGenFunction::TCK_Load);
|
|
// FIXME: Do we also need to handle property references here?
|
|
if (LV.isSimple())
|
|
CGF.EmitDynamicCast(LV.getAddress(CGF), cast<CXXDynamicCastExpr>(E));
|
|
else
|
|
CGF.CGM.ErrorUnsupported(E, "non-simple lvalue dynamic_cast");
|
|
|
|
if (!Dest.isIgnored())
|
|
CGF.CGM.ErrorUnsupported(E, "lvalue dynamic_cast with a destination");
|
|
break;
|
|
}
|
|
|
|
case CK_ToUnion: {
|
|
// Evaluate even if the destination is ignored.
|
|
if (Dest.isIgnored()) {
|
|
CGF.EmitAnyExpr(E->getSubExpr(), AggValueSlot::ignored(),
|
|
/*ignoreResult=*/true);
|
|
break;
|
|
}
|
|
|
|
// GCC union extension
|
|
QualType Ty = E->getSubExpr()->getType();
|
|
Address CastPtr =
|
|
Builder.CreateElementBitCast(Dest.getAddress(), CGF.ConvertType(Ty));
|
|
EmitInitializationToLValue(E->getSubExpr(),
|
|
CGF.MakeAddrLValue(CastPtr, Ty));
|
|
break;
|
|
}
|
|
|
|
case CK_LValueToRValueBitCast: {
|
|
if (Dest.isIgnored()) {
|
|
CGF.EmitAnyExpr(E->getSubExpr(), AggValueSlot::ignored(),
|
|
/*ignoreResult=*/true);
|
|
break;
|
|
}
|
|
|
|
LValue SourceLV = CGF.EmitLValue(E->getSubExpr());
|
|
Address SourceAddress =
|
|
Builder.CreateElementBitCast(SourceLV.getAddress(CGF), CGF.Int8Ty);
|
|
Address DestAddress =
|
|
Builder.CreateElementBitCast(Dest.getAddress(), CGF.Int8Ty);
|
|
llvm::Value *SizeVal = llvm::ConstantInt::get(
|
|
CGF.SizeTy,
|
|
CGF.getContext().getTypeSizeInChars(E->getType()).getQuantity());
|
|
Builder.CreateMemCpy(DestAddress, SourceAddress, SizeVal);
|
|
break;
|
|
}
|
|
|
|
case CK_DerivedToBase:
|
|
case CK_BaseToDerived:
|
|
case CK_UncheckedDerivedToBase: {
|
|
llvm_unreachable("cannot perform hierarchy conversion in EmitAggExpr: "
|
|
"should have been unpacked before we got here");
|
|
}
|
|
|
|
case CK_NonAtomicToAtomic:
|
|
case CK_AtomicToNonAtomic: {
|
|
bool isToAtomic = (E->getCastKind() == CK_NonAtomicToAtomic);
|
|
|
|
// Determine the atomic and value types.
|
|
QualType atomicType = E->getSubExpr()->getType();
|
|
QualType valueType = E->getType();
|
|
if (isToAtomic) std::swap(atomicType, valueType);
|
|
|
|
assert(atomicType->isAtomicType());
|
|
assert(CGF.getContext().hasSameUnqualifiedType(valueType,
|
|
atomicType->castAs<AtomicType>()->getValueType()));
|
|
|
|
// Just recurse normally if we're ignoring the result or the
|
|
// atomic type doesn't change representation.
|
|
if (Dest.isIgnored() || !CGF.CGM.isPaddedAtomicType(atomicType)) {
|
|
return Visit(E->getSubExpr());
|
|
}
|
|
|
|
CastKind peepholeTarget =
|
|
(isToAtomic ? CK_AtomicToNonAtomic : CK_NonAtomicToAtomic);
|
|
|
|
// These two cases are reverses of each other; try to peephole them.
|
|
if (Expr *op =
|
|
findPeephole(E->getSubExpr(), peepholeTarget, CGF.getContext())) {
|
|
assert(CGF.getContext().hasSameUnqualifiedType(op->getType(),
|
|
E->getType()) &&
|
|
"peephole significantly changed types?");
|
|
return Visit(op);
|
|
}
|
|
|
|
// If we're converting an r-value of non-atomic type to an r-value
|
|
// of atomic type, just emit directly into the relevant sub-object.
|
|
if (isToAtomic) {
|
|
AggValueSlot valueDest = Dest;
|
|
if (!valueDest.isIgnored() && CGF.CGM.isPaddedAtomicType(atomicType)) {
|
|
// Zero-initialize. (Strictly speaking, we only need to initialize
|
|
// the padding at the end, but this is simpler.)
|
|
if (!Dest.isZeroed())
|
|
CGF.EmitNullInitialization(Dest.getAddress(), atomicType);
|
|
|
|
// Build a GEP to refer to the subobject.
|
|
Address valueAddr =
|
|
CGF.Builder.CreateStructGEP(valueDest.getAddress(), 0);
|
|
valueDest = AggValueSlot::forAddr(valueAddr,
|
|
valueDest.getQualifiers(),
|
|
valueDest.isExternallyDestructed(),
|
|
valueDest.requiresGCollection(),
|
|
valueDest.isPotentiallyAliased(),
|
|
AggValueSlot::DoesNotOverlap,
|
|
AggValueSlot::IsZeroed);
|
|
}
|
|
|
|
CGF.EmitAggExpr(E->getSubExpr(), valueDest);
|
|
return;
|
|
}
|
|
|
|
// Otherwise, we're converting an atomic type to a non-atomic type.
|
|
// Make an atomic temporary, emit into that, and then copy the value out.
|
|
AggValueSlot atomicSlot =
|
|
CGF.CreateAggTemp(atomicType, "atomic-to-nonatomic.temp");
|
|
CGF.EmitAggExpr(E->getSubExpr(), atomicSlot);
|
|
|
|
Address valueAddr = Builder.CreateStructGEP(atomicSlot.getAddress(), 0);
|
|
RValue rvalue = RValue::getAggregate(valueAddr, atomicSlot.isVolatile());
|
|
return EmitFinalDestCopy(valueType, rvalue);
|
|
}
|
|
case CK_AddressSpaceConversion:
|
|
return Visit(E->getSubExpr());
|
|
|
|
case CK_LValueToRValue:
|
|
// If we're loading from a volatile type, force the destination
|
|
// into existence.
|
|
if (E->getSubExpr()->getType().isVolatileQualified()) {
|
|
bool Destruct =
|
|
!Dest.isExternallyDestructed() &&
|
|
E->getType().isDestructedType() == QualType::DK_nontrivial_c_struct;
|
|
if (Destruct)
|
|
Dest.setExternallyDestructed();
|
|
EnsureDest(E->getType());
|
|
Visit(E->getSubExpr());
|
|
|
|
if (Destruct)
|
|
CGF.pushDestroy(QualType::DK_nontrivial_c_struct, Dest.getAddress(),
|
|
E->getType());
|
|
|
|
return;
|
|
}
|
|
|
|
LLVM_FALLTHROUGH;
|
|
|
|
|
|
case CK_NoOp:
|
|
case CK_UserDefinedConversion:
|
|
case CK_ConstructorConversion:
|
|
assert(CGF.getContext().hasSameUnqualifiedType(E->getSubExpr()->getType(),
|
|
E->getType()) &&
|
|
"Implicit cast types must be compatible");
|
|
Visit(E->getSubExpr());
|
|
break;
|
|
|
|
case CK_LValueBitCast:
|
|
llvm_unreachable("should not be emitting lvalue bitcast as rvalue");
|
|
|
|
case CK_Dependent:
|
|
case CK_BitCast:
|
|
case CK_ArrayToPointerDecay:
|
|
case CK_FunctionToPointerDecay:
|
|
case CK_NullToPointer:
|
|
case CK_NullToMemberPointer:
|
|
case CK_BaseToDerivedMemberPointer:
|
|
case CK_DerivedToBaseMemberPointer:
|
|
case CK_MemberPointerToBoolean:
|
|
case CK_ReinterpretMemberPointer:
|
|
case CK_IntegralToPointer:
|
|
case CK_PointerToIntegral:
|
|
case CK_PointerToBoolean:
|
|
case CK_ToVoid:
|
|
case CK_VectorSplat:
|
|
case CK_IntegralCast:
|
|
case CK_BooleanToSignedIntegral:
|
|
case CK_IntegralToBoolean:
|
|
case CK_IntegralToFloating:
|
|
case CK_FloatingToIntegral:
|
|
case CK_FloatingToBoolean:
|
|
case CK_FloatingCast:
|
|
case CK_CPointerToObjCPointerCast:
|
|
case CK_BlockPointerToObjCPointerCast:
|
|
case CK_AnyPointerToBlockPointerCast:
|
|
case CK_ObjCObjectLValueCast:
|
|
case CK_FloatingRealToComplex:
|
|
case CK_FloatingComplexToReal:
|
|
case CK_FloatingComplexToBoolean:
|
|
case CK_FloatingComplexCast:
|
|
case CK_FloatingComplexToIntegralComplex:
|
|
case CK_IntegralRealToComplex:
|
|
case CK_IntegralComplexToReal:
|
|
case CK_IntegralComplexToBoolean:
|
|
case CK_IntegralComplexCast:
|
|
case CK_IntegralComplexToFloatingComplex:
|
|
case CK_ARCProduceObject:
|
|
case CK_ARCConsumeObject:
|
|
case CK_ARCReclaimReturnedObject:
|
|
case CK_ARCExtendBlockObject:
|
|
case CK_CopyAndAutoreleaseBlockObject:
|
|
case CK_BuiltinFnToFnPtr:
|
|
case CK_ZeroToOCLOpaqueType:
|
|
|
|
case CK_IntToOCLSampler:
|
|
case CK_FloatingToFixedPoint:
|
|
case CK_FixedPointToFloating:
|
|
case CK_FixedPointCast:
|
|
case CK_FixedPointToBoolean:
|
|
case CK_FixedPointToIntegral:
|
|
case CK_IntegralToFixedPoint:
|
|
llvm_unreachable("cast kind invalid for aggregate types");
|
|
}
|
|
}
|
|
|
|
void AggExprEmitter::VisitCallExpr(const CallExpr *E) {
|
|
if (E->getCallReturnType(CGF.getContext())->isReferenceType()) {
|
|
EmitAggLoadOfLValue(E);
|
|
return;
|
|
}
|
|
|
|
withReturnValueSlot(E, [&](ReturnValueSlot Slot) {
|
|
return CGF.EmitCallExpr(E, Slot);
|
|
});
|
|
}
|
|
|
|
void AggExprEmitter::VisitObjCMessageExpr(ObjCMessageExpr *E) {
|
|
withReturnValueSlot(E, [&](ReturnValueSlot Slot) {
|
|
return CGF.EmitObjCMessageExpr(E, Slot);
|
|
});
|
|
}
|
|
|
|
void AggExprEmitter::VisitBinComma(const BinaryOperator *E) {
|
|
CGF.EmitIgnoredExpr(E->getLHS());
|
|
Visit(E->getRHS());
|
|
}
|
|
|
|
void AggExprEmitter::VisitStmtExpr(const StmtExpr *E) {
|
|
CodeGenFunction::StmtExprEvaluation eval(CGF);
|
|
CGF.EmitCompoundStmt(*E->getSubStmt(), true, Dest);
|
|
}
|
|
|
|
enum CompareKind {
|
|
CK_Less,
|
|
CK_Greater,
|
|
CK_Equal,
|
|
};
|
|
|
|
static llvm::Value *EmitCompare(CGBuilderTy &Builder, CodeGenFunction &CGF,
|
|
const BinaryOperator *E, llvm::Value *LHS,
|
|
llvm::Value *RHS, CompareKind Kind,
|
|
const char *NameSuffix = "") {
|
|
QualType ArgTy = E->getLHS()->getType();
|
|
if (const ComplexType *CT = ArgTy->getAs<ComplexType>())
|
|
ArgTy = CT->getElementType();
|
|
|
|
if (const auto *MPT = ArgTy->getAs<MemberPointerType>()) {
|
|
assert(Kind == CK_Equal &&
|
|
"member pointers may only be compared for equality");
|
|
return CGF.CGM.getCXXABI().EmitMemberPointerComparison(
|
|
CGF, LHS, RHS, MPT, /*IsInequality*/ false);
|
|
}
|
|
|
|
// Compute the comparison instructions for the specified comparison kind.
|
|
struct CmpInstInfo {
|
|
const char *Name;
|
|
llvm::CmpInst::Predicate FCmp;
|
|
llvm::CmpInst::Predicate SCmp;
|
|
llvm::CmpInst::Predicate UCmp;
|
|
};
|
|
CmpInstInfo InstInfo = [&]() -> CmpInstInfo {
|
|
using FI = llvm::FCmpInst;
|
|
using II = llvm::ICmpInst;
|
|
switch (Kind) {
|
|
case CK_Less:
|
|
return {"cmp.lt", FI::FCMP_OLT, II::ICMP_SLT, II::ICMP_ULT};
|
|
case CK_Greater:
|
|
return {"cmp.gt", FI::FCMP_OGT, II::ICMP_SGT, II::ICMP_UGT};
|
|
case CK_Equal:
|
|
return {"cmp.eq", FI::FCMP_OEQ, II::ICMP_EQ, II::ICMP_EQ};
|
|
}
|
|
llvm_unreachable("Unrecognised CompareKind enum");
|
|
}();
|
|
|
|
if (ArgTy->hasFloatingRepresentation())
|
|
return Builder.CreateFCmp(InstInfo.FCmp, LHS, RHS,
|
|
llvm::Twine(InstInfo.Name) + NameSuffix);
|
|
if (ArgTy->isIntegralOrEnumerationType() || ArgTy->isPointerType()) {
|
|
auto Inst =
|
|
ArgTy->hasSignedIntegerRepresentation() ? InstInfo.SCmp : InstInfo.UCmp;
|
|
return Builder.CreateICmp(Inst, LHS, RHS,
|
|
llvm::Twine(InstInfo.Name) + NameSuffix);
|
|
}
|
|
|
|
llvm_unreachable("unsupported aggregate binary expression should have "
|
|
"already been handled");
|
|
}
|
|
|
|
void AggExprEmitter::VisitBinCmp(const BinaryOperator *E) {
|
|
using llvm::BasicBlock;
|
|
using llvm::PHINode;
|
|
using llvm::Value;
|
|
assert(CGF.getContext().hasSameType(E->getLHS()->getType(),
|
|
E->getRHS()->getType()));
|
|
const ComparisonCategoryInfo &CmpInfo =
|
|
CGF.getContext().CompCategories.getInfoForType(E->getType());
|
|
assert(CmpInfo.Record->isTriviallyCopyable() &&
|
|
"cannot copy non-trivially copyable aggregate");
|
|
|
|
QualType ArgTy = E->getLHS()->getType();
|
|
|
|
if (!ArgTy->isIntegralOrEnumerationType() && !ArgTy->isRealFloatingType() &&
|
|
!ArgTy->isNullPtrType() && !ArgTy->isPointerType() &&
|
|
!ArgTy->isMemberPointerType() && !ArgTy->isAnyComplexType()) {
|
|
return CGF.ErrorUnsupported(E, "aggregate three-way comparison");
|
|
}
|
|
bool IsComplex = ArgTy->isAnyComplexType();
|
|
|
|
// Evaluate the operands to the expression and extract their values.
|
|
auto EmitOperand = [&](Expr *E) -> std::pair<Value *, Value *> {
|
|
RValue RV = CGF.EmitAnyExpr(E);
|
|
if (RV.isScalar())
|
|
return {RV.getScalarVal(), nullptr};
|
|
if (RV.isAggregate())
|
|
return {RV.getAggregatePointer(), nullptr};
|
|
assert(RV.isComplex());
|
|
return RV.getComplexVal();
|
|
};
|
|
auto LHSValues = EmitOperand(E->getLHS()),
|
|
RHSValues = EmitOperand(E->getRHS());
|
|
|
|
auto EmitCmp = [&](CompareKind K) {
|
|
Value *Cmp = EmitCompare(Builder, CGF, E, LHSValues.first, RHSValues.first,
|
|
K, IsComplex ? ".r" : "");
|
|
if (!IsComplex)
|
|
return Cmp;
|
|
assert(K == CompareKind::CK_Equal);
|
|
Value *CmpImag = EmitCompare(Builder, CGF, E, LHSValues.second,
|
|
RHSValues.second, K, ".i");
|
|
return Builder.CreateAnd(Cmp, CmpImag, "and.eq");
|
|
};
|
|
auto EmitCmpRes = [&](const ComparisonCategoryInfo::ValueInfo *VInfo) {
|
|
return Builder.getInt(VInfo->getIntValue());
|
|
};
|
|
|
|
Value *Select;
|
|
if (ArgTy->isNullPtrType()) {
|
|
Select = EmitCmpRes(CmpInfo.getEqualOrEquiv());
|
|
} else if (!CmpInfo.isPartial()) {
|
|
Value *SelectOne =
|
|
Builder.CreateSelect(EmitCmp(CK_Less), EmitCmpRes(CmpInfo.getLess()),
|
|
EmitCmpRes(CmpInfo.getGreater()), "sel.lt");
|
|
Select = Builder.CreateSelect(EmitCmp(CK_Equal),
|
|
EmitCmpRes(CmpInfo.getEqualOrEquiv()),
|
|
SelectOne, "sel.eq");
|
|
} else {
|
|
Value *SelectEq = Builder.CreateSelect(
|
|
EmitCmp(CK_Equal), EmitCmpRes(CmpInfo.getEqualOrEquiv()),
|
|
EmitCmpRes(CmpInfo.getUnordered()), "sel.eq");
|
|
Value *SelectGT = Builder.CreateSelect(EmitCmp(CK_Greater),
|
|
EmitCmpRes(CmpInfo.getGreater()),
|
|
SelectEq, "sel.gt");
|
|
Select = Builder.CreateSelect(
|
|
EmitCmp(CK_Less), EmitCmpRes(CmpInfo.getLess()), SelectGT, "sel.lt");
|
|
}
|
|
// Create the return value in the destination slot.
|
|
EnsureDest(E->getType());
|
|
LValue DestLV = CGF.MakeAddrLValue(Dest.getAddress(), E->getType());
|
|
|
|
// Emit the address of the first (and only) field in the comparison category
|
|
// type, and initialize it from the constant integer value selected above.
|
|
LValue FieldLV = CGF.EmitLValueForFieldInitialization(
|
|
DestLV, *CmpInfo.Record->field_begin());
|
|
CGF.EmitStoreThroughLValue(RValue::get(Select), FieldLV, /*IsInit*/ true);
|
|
|
|
// All done! The result is in the Dest slot.
|
|
}
|
|
|
|
void AggExprEmitter::VisitBinaryOperator(const BinaryOperator *E) {
|
|
if (E->getOpcode() == BO_PtrMemD || E->getOpcode() == BO_PtrMemI)
|
|
VisitPointerToDataMemberBinaryOperator(E);
|
|
else
|
|
CGF.ErrorUnsupported(E, "aggregate binary expression");
|
|
}
|
|
|
|
void AggExprEmitter::VisitPointerToDataMemberBinaryOperator(
|
|
const BinaryOperator *E) {
|
|
LValue LV = CGF.EmitPointerToDataMemberBinaryExpr(E);
|
|
EmitFinalDestCopy(E->getType(), LV);
|
|
}
|
|
|
|
/// Is the value of the given expression possibly a reference to or
|
|
/// into a __block variable?
|
|
static bool isBlockVarRef(const Expr *E) {
|
|
// Make sure we look through parens.
|
|
E = E->IgnoreParens();
|
|
|
|
// Check for a direct reference to a __block variable.
|
|
if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
|
|
const VarDecl *var = dyn_cast<VarDecl>(DRE->getDecl());
|
|
return (var && var->hasAttr<BlocksAttr>());
|
|
}
|
|
|
|
// More complicated stuff.
|
|
|
|
// Binary operators.
|
|
if (const BinaryOperator *op = dyn_cast<BinaryOperator>(E)) {
|
|
// For an assignment or pointer-to-member operation, just care
|
|
// about the LHS.
|
|
if (op->isAssignmentOp() || op->isPtrMemOp())
|
|
return isBlockVarRef(op->getLHS());
|
|
|
|
// For a comma, just care about the RHS.
|
|
if (op->getOpcode() == BO_Comma)
|
|
return isBlockVarRef(op->getRHS());
|
|
|
|
// FIXME: pointer arithmetic?
|
|
return false;
|
|
|
|
// Check both sides of a conditional operator.
|
|
} else if (const AbstractConditionalOperator *op
|
|
= dyn_cast<AbstractConditionalOperator>(E)) {
|
|
return isBlockVarRef(op->getTrueExpr())
|
|
|| isBlockVarRef(op->getFalseExpr());
|
|
|
|
// OVEs are required to support BinaryConditionalOperators.
|
|
} else if (const OpaqueValueExpr *op
|
|
= dyn_cast<OpaqueValueExpr>(E)) {
|
|
if (const Expr *src = op->getSourceExpr())
|
|
return isBlockVarRef(src);
|
|
|
|
// Casts are necessary to get things like (*(int*)&var) = foo().
|
|
// We don't really care about the kind of cast here, except
|
|
// we don't want to look through l2r casts, because it's okay
|
|
// to get the *value* in a __block variable.
|
|
} else if (const CastExpr *cast = dyn_cast<CastExpr>(E)) {
|
|
if (cast->getCastKind() == CK_LValueToRValue)
|
|
return false;
|
|
return isBlockVarRef(cast->getSubExpr());
|
|
|
|
// Handle unary operators. Again, just aggressively look through
|
|
// it, ignoring the operation.
|
|
} else if (const UnaryOperator *uop = dyn_cast<UnaryOperator>(E)) {
|
|
return isBlockVarRef(uop->getSubExpr());
|
|
|
|
// Look into the base of a field access.
|
|
} else if (const MemberExpr *mem = dyn_cast<MemberExpr>(E)) {
|
|
return isBlockVarRef(mem->getBase());
|
|
|
|
// Look into the base of a subscript.
|
|
} else if (const ArraySubscriptExpr *sub = dyn_cast<ArraySubscriptExpr>(E)) {
|
|
return isBlockVarRef(sub->getBase());
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
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");
|
|
|
|
// If the LHS might be a __block variable, and the RHS can
|
|
// potentially cause a block copy, we need to evaluate the RHS first
|
|
// so that the assignment goes the right place.
|
|
// This is pretty semantically fragile.
|
|
if (isBlockVarRef(E->getLHS()) &&
|
|
E->getRHS()->HasSideEffects(CGF.getContext())) {
|
|
// Ensure that we have a destination, and evaluate the RHS into that.
|
|
EnsureDest(E->getRHS()->getType());
|
|
Visit(E->getRHS());
|
|
|
|
// Now emit the LHS and copy into it.
|
|
LValue LHS = CGF.EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store);
|
|
|
|
// That copy is an atomic copy if the LHS is atomic.
|
|
if (LHS.getType()->isAtomicType() ||
|
|
CGF.LValueIsSuitableForInlineAtomic(LHS)) {
|
|
CGF.EmitAtomicStore(Dest.asRValue(), LHS, /*isInit*/ false);
|
|
return;
|
|
}
|
|
|
|
EmitCopy(E->getLHS()->getType(),
|
|
AggValueSlot::forLValue(LHS, CGF, AggValueSlot::IsDestructed,
|
|
needsGC(E->getLHS()->getType()),
|
|
AggValueSlot::IsAliased,
|
|
AggValueSlot::MayOverlap),
|
|
Dest);
|
|
return;
|
|
}
|
|
|
|
LValue LHS = CGF.EmitLValue(E->getLHS());
|
|
|
|
// If we have an atomic type, evaluate into the destination and then
|
|
// do an atomic copy.
|
|
if (LHS.getType()->isAtomicType() ||
|
|
CGF.LValueIsSuitableForInlineAtomic(LHS)) {
|
|
EnsureDest(E->getRHS()->getType());
|
|
Visit(E->getRHS());
|
|
CGF.EmitAtomicStore(Dest.asRValue(), LHS, /*isInit*/ false);
|
|
return;
|
|
}
|
|
|
|
// Codegen the RHS so that it stores directly into the LHS.
|
|
AggValueSlot LHSSlot = AggValueSlot::forLValue(
|
|
LHS, CGF, AggValueSlot::IsDestructed, needsGC(E->getLHS()->getType()),
|
|
AggValueSlot::IsAliased, AggValueSlot::MayOverlap);
|
|
// A non-volatile aggregate destination might have volatile member.
|
|
if (!LHSSlot.isVolatile() &&
|
|
CGF.hasVolatileMember(E->getLHS()->getType()))
|
|
LHSSlot.setVolatile(true);
|
|
|
|
CGF.EmitAggExpr(E->getRHS(), LHSSlot);
|
|
|
|
// Copy into the destination if the assignment isn't ignored.
|
|
EmitFinalDestCopy(E->getType(), LHS);
|
|
|
|
if (!Dest.isIgnored() && !Dest.isExternallyDestructed() &&
|
|
E->getType().isDestructedType() == QualType::DK_nontrivial_c_struct)
|
|
CGF.pushDestroy(QualType::DK_nontrivial_c_struct, Dest.getAddress(),
|
|
E->getType());
|
|
}
|
|
|
|
void AggExprEmitter::
|
|
VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) {
|
|
llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
|
|
llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
|
|
llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
|
|
|
|
// Bind the common expression if necessary.
|
|
CodeGenFunction::OpaqueValueMapping binding(CGF, E);
|
|
|
|
CodeGenFunction::ConditionalEvaluation eval(CGF);
|
|
CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock,
|
|
CGF.getProfileCount(E));
|
|
|
|
// Save whether the destination's lifetime is externally managed.
|
|
bool isExternallyDestructed = Dest.isExternallyDestructed();
|
|
bool destructNonTrivialCStruct =
|
|
!isExternallyDestructed &&
|
|
E->getType().isDestructedType() == QualType::DK_nontrivial_c_struct;
|
|
isExternallyDestructed |= destructNonTrivialCStruct;
|
|
Dest.setExternallyDestructed(isExternallyDestructed);
|
|
|
|
eval.begin(CGF);
|
|
CGF.EmitBlock(LHSBlock);
|
|
CGF.incrementProfileCounter(E);
|
|
Visit(E->getTrueExpr());
|
|
eval.end(CGF);
|
|
|
|
assert(CGF.HaveInsertPoint() && "expression evaluation ended with no IP!");
|
|
CGF.Builder.CreateBr(ContBlock);
|
|
|
|
// If the result of an agg expression is unused, then the emission
|
|
// of the LHS might need to create a destination slot. That's fine
|
|
// with us, and we can safely emit the RHS into the same slot, but
|
|
// we shouldn't claim that it's already being destructed.
|
|
Dest.setExternallyDestructed(isExternallyDestructed);
|
|
|
|
eval.begin(CGF);
|
|
CGF.EmitBlock(RHSBlock);
|
|
Visit(E->getFalseExpr());
|
|
eval.end(CGF);
|
|
|
|
if (destructNonTrivialCStruct)
|
|
CGF.pushDestroy(QualType::DK_nontrivial_c_struct, Dest.getAddress(),
|
|
E->getType());
|
|
|
|
CGF.EmitBlock(ContBlock);
|
|
}
|
|
|
|
void AggExprEmitter::VisitChooseExpr(const ChooseExpr *CE) {
|
|
Visit(CE->getChosenSubExpr());
|
|
}
|
|
|
|
void AggExprEmitter::VisitVAArgExpr(VAArgExpr *VE) {
|
|
Address ArgValue = Address::invalid();
|
|
Address ArgPtr = CGF.EmitVAArg(VE, ArgValue);
|
|
|
|
// If EmitVAArg fails, emit an error.
|
|
if (!ArgPtr.isValid()) {
|
|
CGF.ErrorUnsupported(VE, "aggregate va_arg expression");
|
|
return;
|
|
}
|
|
|
|
EmitFinalDestCopy(VE->getType(), CGF.MakeAddrLValue(ArgPtr, VE->getType()));
|
|
}
|
|
|
|
void AggExprEmitter::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
|
|
// Ensure that we have a slot, but if we already do, remember
|
|
// whether it was externally destructed.
|
|
bool wasExternallyDestructed = Dest.isExternallyDestructed();
|
|
EnsureDest(E->getType());
|
|
|
|
// We're going to push a destructor if there isn't already one.
|
|
Dest.setExternallyDestructed();
|
|
|
|
Visit(E->getSubExpr());
|
|
|
|
// Push that destructor we promised.
|
|
if (!wasExternallyDestructed)
|
|
CGF.EmitCXXTemporary(E->getTemporary(), E->getType(), Dest.getAddress());
|
|
}
|
|
|
|
void
|
|
AggExprEmitter::VisitCXXConstructExpr(const CXXConstructExpr *E) {
|
|
AggValueSlot Slot = EnsureSlot(E->getType());
|
|
CGF.EmitCXXConstructExpr(E, Slot);
|
|
}
|
|
|
|
void AggExprEmitter::VisitCXXInheritedCtorInitExpr(
|
|
const CXXInheritedCtorInitExpr *E) {
|
|
AggValueSlot Slot = EnsureSlot(E->getType());
|
|
CGF.EmitInheritedCXXConstructorCall(
|
|
E->getConstructor(), E->constructsVBase(), Slot.getAddress(),
|
|
E->inheritedFromVBase(), E);
|
|
}
|
|
|
|
void
|
|
AggExprEmitter::VisitLambdaExpr(LambdaExpr *E) {
|
|
AggValueSlot Slot = EnsureSlot(E->getType());
|
|
LValue SlotLV = CGF.MakeAddrLValue(Slot.getAddress(), E->getType());
|
|
|
|
// We'll need to enter cleanup scopes in case any of the element
|
|
// initializers throws an exception.
|
|
SmallVector<EHScopeStack::stable_iterator, 16> Cleanups;
|
|
llvm::Instruction *CleanupDominator = nullptr;
|
|
|
|
CXXRecordDecl::field_iterator CurField = E->getLambdaClass()->field_begin();
|
|
for (LambdaExpr::const_capture_init_iterator i = E->capture_init_begin(),
|
|
e = E->capture_init_end();
|
|
i != e; ++i, ++CurField) {
|
|
// Emit initialization
|
|
LValue LV = CGF.EmitLValueForFieldInitialization(SlotLV, *CurField);
|
|
if (CurField->hasCapturedVLAType()) {
|
|
CGF.EmitLambdaVLACapture(CurField->getCapturedVLAType(), LV);
|
|
continue;
|
|
}
|
|
|
|
EmitInitializationToLValue(*i, LV);
|
|
|
|
// Push a destructor if necessary.
|
|
if (QualType::DestructionKind DtorKind =
|
|
CurField->getType().isDestructedType()) {
|
|
assert(LV.isSimple());
|
|
if (CGF.needsEHCleanup(DtorKind)) {
|
|
if (!CleanupDominator)
|
|
CleanupDominator = CGF.Builder.CreateAlignedLoad(
|
|
CGF.Int8Ty,
|
|
llvm::Constant::getNullValue(CGF.Int8PtrTy),
|
|
CharUnits::One()); // placeholder
|
|
|
|
CGF.pushDestroy(EHCleanup, LV.getAddress(CGF), CurField->getType(),
|
|
CGF.getDestroyer(DtorKind), false);
|
|
Cleanups.push_back(CGF.EHStack.stable_begin());
|
|
}
|
|
}
|
|
}
|
|
|
|
// Deactivate all the partial cleanups in reverse order, which
|
|
// generally means popping them.
|
|
for (unsigned i = Cleanups.size(); i != 0; --i)
|
|
CGF.DeactivateCleanupBlock(Cleanups[i-1], CleanupDominator);
|
|
|
|
// Destroy the placeholder if we made one.
|
|
if (CleanupDominator)
|
|
CleanupDominator->eraseFromParent();
|
|
}
|
|
|
|
void AggExprEmitter::VisitExprWithCleanups(ExprWithCleanups *E) {
|
|
CodeGenFunction::RunCleanupsScope cleanups(CGF);
|
|
Visit(E->getSubExpr());
|
|
}
|
|
|
|
void AggExprEmitter::VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) {
|
|
QualType T = E->getType();
|
|
AggValueSlot Slot = EnsureSlot(T);
|
|
EmitNullInitializationToLValue(CGF.MakeAddrLValue(Slot.getAddress(), T));
|
|
}
|
|
|
|
void AggExprEmitter::VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
|
|
QualType T = E->getType();
|
|
AggValueSlot Slot = EnsureSlot(T);
|
|
EmitNullInitializationToLValue(CGF.MakeAddrLValue(Slot.getAddress(), T));
|
|
}
|
|
|
|
/// Determine whether the given cast kind is known to always convert values
|
|
/// with all zero bits in their value representation to values with all zero
|
|
/// bits in their value representation.
|
|
static bool castPreservesZero(const CastExpr *CE) {
|
|
switch (CE->getCastKind()) {
|
|
// No-ops.
|
|
case CK_NoOp:
|
|
case CK_UserDefinedConversion:
|
|
case CK_ConstructorConversion:
|
|
case CK_BitCast:
|
|
case CK_ToUnion:
|
|
case CK_ToVoid:
|
|
// Conversions between (possibly-complex) integral, (possibly-complex)
|
|
// floating-point, and bool.
|
|
case CK_BooleanToSignedIntegral:
|
|
case CK_FloatingCast:
|
|
case CK_FloatingComplexCast:
|
|
case CK_FloatingComplexToBoolean:
|
|
case CK_FloatingComplexToIntegralComplex:
|
|
case CK_FloatingComplexToReal:
|
|
case CK_FloatingRealToComplex:
|
|
case CK_FloatingToBoolean:
|
|
case CK_FloatingToIntegral:
|
|
case CK_IntegralCast:
|
|
case CK_IntegralComplexCast:
|
|
case CK_IntegralComplexToBoolean:
|
|
case CK_IntegralComplexToFloatingComplex:
|
|
case CK_IntegralComplexToReal:
|
|
case CK_IntegralRealToComplex:
|
|
case CK_IntegralToBoolean:
|
|
case CK_IntegralToFloating:
|
|
// Reinterpreting integers as pointers and vice versa.
|
|
case CK_IntegralToPointer:
|
|
case CK_PointerToIntegral:
|
|
// Language extensions.
|
|
case CK_VectorSplat:
|
|
case CK_NonAtomicToAtomic:
|
|
case CK_AtomicToNonAtomic:
|
|
return true;
|
|
|
|
case CK_BaseToDerivedMemberPointer:
|
|
case CK_DerivedToBaseMemberPointer:
|
|
case CK_MemberPointerToBoolean:
|
|
case CK_NullToMemberPointer:
|
|
case CK_ReinterpretMemberPointer:
|
|
// FIXME: ABI-dependent.
|
|
return false;
|
|
|
|
case CK_AnyPointerToBlockPointerCast:
|
|
case CK_BlockPointerToObjCPointerCast:
|
|
case CK_CPointerToObjCPointerCast:
|
|
case CK_ObjCObjectLValueCast:
|
|
case CK_IntToOCLSampler:
|
|
case CK_ZeroToOCLOpaqueType:
|
|
// FIXME: Check these.
|
|
return false;
|
|
|
|
case CK_FixedPointCast:
|
|
case CK_FixedPointToBoolean:
|
|
case CK_FixedPointToFloating:
|
|
case CK_FixedPointToIntegral:
|
|
case CK_FloatingToFixedPoint:
|
|
case CK_IntegralToFixedPoint:
|
|
// FIXME: Do all fixed-point types represent zero as all 0 bits?
|
|
return false;
|
|
|
|
case CK_AddressSpaceConversion:
|
|
case CK_BaseToDerived:
|
|
case CK_DerivedToBase:
|
|
case CK_Dynamic:
|
|
case CK_NullToPointer:
|
|
case CK_PointerToBoolean:
|
|
// FIXME: Preserves zeroes only if zero pointers and null pointers have the
|
|
// same representation in all involved address spaces.
|
|
return false;
|
|
|
|
case CK_ARCConsumeObject:
|
|
case CK_ARCExtendBlockObject:
|
|
case CK_ARCProduceObject:
|
|
case CK_ARCReclaimReturnedObject:
|
|
case CK_CopyAndAutoreleaseBlockObject:
|
|
case CK_ArrayToPointerDecay:
|
|
case CK_FunctionToPointerDecay:
|
|
case CK_BuiltinFnToFnPtr:
|
|
case CK_Dependent:
|
|
case CK_LValueBitCast:
|
|
case CK_LValueToRValue:
|
|
case CK_LValueToRValueBitCast:
|
|
case CK_UncheckedDerivedToBase:
|
|
return false;
|
|
}
|
|
llvm_unreachable("Unhandled clang::CastKind enum");
|
|
}
|
|
|
|
/// isSimpleZero - If emitting this value will obviously just cause a store of
|
|
/// zero to memory, return true. This can return false if uncertain, so it just
|
|
/// handles simple cases.
|
|
static bool isSimpleZero(const Expr *E, CodeGenFunction &CGF) {
|
|
E = E->IgnoreParens();
|
|
while (auto *CE = dyn_cast<CastExpr>(E)) {
|
|
if (!castPreservesZero(CE))
|
|
break;
|
|
E = CE->getSubExpr()->IgnoreParens();
|
|
}
|
|
|
|
// 0
|
|
if (const IntegerLiteral *IL = dyn_cast<IntegerLiteral>(E))
|
|
return IL->getValue() == 0;
|
|
// +0.0
|
|
if (const FloatingLiteral *FL = dyn_cast<FloatingLiteral>(E))
|
|
return FL->getValue().isPosZero();
|
|
// int()
|
|
if ((isa<ImplicitValueInitExpr>(E) || isa<CXXScalarValueInitExpr>(E)) &&
|
|
CGF.getTypes().isZeroInitializable(E->getType()))
|
|
return true;
|
|
// (int*)0 - Null pointer expressions.
|
|
if (const CastExpr *ICE = dyn_cast<CastExpr>(E))
|
|
return ICE->getCastKind() == CK_NullToPointer &&
|
|
CGF.getTypes().isPointerZeroInitializable(E->getType()) &&
|
|
!E->HasSideEffects(CGF.getContext());
|
|
// '\0'
|
|
if (const CharacterLiteral *CL = dyn_cast<CharacterLiteral>(E))
|
|
return CL->getValue() == 0;
|
|
|
|
// Otherwise, hard case: conservatively return false.
|
|
return false;
|
|
}
|
|
|
|
|
|
void
|
|
AggExprEmitter::EmitInitializationToLValue(Expr *E, LValue LV) {
|
|
QualType type = LV.getType();
|
|
// FIXME: Ignore result?
|
|
// FIXME: Are initializers affected by volatile?
|
|
if (Dest.isZeroed() && isSimpleZero(E, CGF)) {
|
|
// Storing "i32 0" to a zero'd memory location is a noop.
|
|
return;
|
|
} else if (isa<ImplicitValueInitExpr>(E) || isa<CXXScalarValueInitExpr>(E)) {
|
|
return EmitNullInitializationToLValue(LV);
|
|
} else if (isa<NoInitExpr>(E)) {
|
|
// Do nothing.
|
|
return;
|
|
} else if (type->isReferenceType()) {
|
|
RValue RV = CGF.EmitReferenceBindingToExpr(E);
|
|
return CGF.EmitStoreThroughLValue(RV, LV);
|
|
}
|
|
|
|
switch (CGF.getEvaluationKind(type)) {
|
|
case TEK_Complex:
|
|
CGF.EmitComplexExprIntoLValue(E, LV, /*isInit*/ true);
|
|
return;
|
|
case TEK_Aggregate:
|
|
CGF.EmitAggExpr(
|
|
E, AggValueSlot::forLValue(LV, CGF, AggValueSlot::IsDestructed,
|
|
AggValueSlot::DoesNotNeedGCBarriers,
|
|
AggValueSlot::IsNotAliased,
|
|
AggValueSlot::MayOverlap, Dest.isZeroed()));
|
|
return;
|
|
case TEK_Scalar:
|
|
if (LV.isSimple()) {
|
|
CGF.EmitScalarInit(E, /*D=*/nullptr, LV, /*Captured=*/false);
|
|
} else {
|
|
CGF.EmitStoreThroughLValue(RValue::get(CGF.EmitScalarExpr(E)), LV);
|
|
}
|
|
return;
|
|
}
|
|
llvm_unreachable("bad evaluation kind");
|
|
}
|
|
|
|
void AggExprEmitter::EmitNullInitializationToLValue(LValue lv) {
|
|
QualType type = lv.getType();
|
|
|
|
// If the destination slot is already zeroed out before the aggregate is
|
|
// copied into it, we don't have to emit any zeros here.
|
|
if (Dest.isZeroed() && CGF.getTypes().isZeroInitializable(type))
|
|
return;
|
|
|
|
if (CGF.hasScalarEvaluationKind(type)) {
|
|
// For non-aggregates, we can store the appropriate null constant.
|
|
llvm::Value *null = CGF.CGM.EmitNullConstant(type);
|
|
// Note that the following is not equivalent to
|
|
// EmitStoreThroughBitfieldLValue for ARC types.
|
|
if (lv.isBitField()) {
|
|
CGF.EmitStoreThroughBitfieldLValue(RValue::get(null), lv);
|
|
} else {
|
|
assert(lv.isSimple());
|
|
CGF.EmitStoreOfScalar(null, lv, /* isInitialization */ true);
|
|
}
|
|
} else {
|
|
// 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.EmitNullInitialization(lv.getAddress(CGF), lv.getType());
|
|
}
|
|
}
|
|
|
|
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->getType(), CGF.MakeAddrLValue(GV, E->getType()));
|
|
return;
|
|
}
|
|
#endif
|
|
if (E->hadArrayRangeDesignator())
|
|
CGF.ErrorUnsupported(E, "GNU array range designator extension");
|
|
|
|
if (E->isTransparent())
|
|
return Visit(E->getInit(0));
|
|
|
|
AggValueSlot Dest = EnsureSlot(E->getType());
|
|
|
|
LValue DestLV = CGF.MakeAddrLValue(Dest.getAddress(), E->getType());
|
|
|
|
// Handle initialization of an array.
|
|
if (E->getType()->isArrayType()) {
|
|
auto AType = cast<llvm::ArrayType>(Dest.getAddress().getElementType());
|
|
EmitArrayInit(Dest.getAddress(), AType, E->getType(), E);
|
|
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 *record = E->getType()->castAs<RecordType>()->getDecl();
|
|
|
|
// We'll need to enter cleanup scopes in case any of the element
|
|
// initializers throws an exception.
|
|
SmallVector<EHScopeStack::stable_iterator, 16> cleanups;
|
|
llvm::Instruction *cleanupDominator = nullptr;
|
|
auto addCleanup = [&](const EHScopeStack::stable_iterator &cleanup) {
|
|
cleanups.push_back(cleanup);
|
|
if (!cleanupDominator) // create placeholder once needed
|
|
cleanupDominator = CGF.Builder.CreateAlignedLoad(
|
|
CGF.Int8Ty, llvm::Constant::getNullValue(CGF.Int8PtrTy),
|
|
CharUnits::One());
|
|
};
|
|
|
|
unsigned curInitIndex = 0;
|
|
|
|
// Emit initialization of base classes.
|
|
if (auto *CXXRD = dyn_cast<CXXRecordDecl>(record)) {
|
|
assert(E->getNumInits() >= CXXRD->getNumBases() &&
|
|
"missing initializer for base class");
|
|
for (auto &Base : CXXRD->bases()) {
|
|
assert(!Base.isVirtual() && "should not see vbases here");
|
|
auto *BaseRD = Base.getType()->getAsCXXRecordDecl();
|
|
Address V = CGF.GetAddressOfDirectBaseInCompleteClass(
|
|
Dest.getAddress(), CXXRD, BaseRD,
|
|
/*isBaseVirtual*/ false);
|
|
AggValueSlot AggSlot = AggValueSlot::forAddr(
|
|
V, Qualifiers(),
|
|
AggValueSlot::IsDestructed,
|
|
AggValueSlot::DoesNotNeedGCBarriers,
|
|
AggValueSlot::IsNotAliased,
|
|
CGF.getOverlapForBaseInit(CXXRD, BaseRD, Base.isVirtual()));
|
|
CGF.EmitAggExpr(E->getInit(curInitIndex++), AggSlot);
|
|
|
|
if (QualType::DestructionKind dtorKind =
|
|
Base.getType().isDestructedType()) {
|
|
CGF.pushDestroy(dtorKind, V, Base.getType());
|
|
addCleanup(CGF.EHStack.stable_begin());
|
|
}
|
|
}
|
|
}
|
|
|
|
// Prepare a 'this' for CXXDefaultInitExprs.
|
|
CodeGenFunction::FieldConstructionScope FCS(CGF, Dest.getAddress());
|
|
|
|
if (record->isUnion()) {
|
|
// 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 (const auto *Field : record->fields())
|
|
assert(Field->isUnnamedBitfield() && "Only unnamed bitfields allowed");
|
|
#endif
|
|
return;
|
|
}
|
|
|
|
// FIXME: volatility
|
|
FieldDecl *Field = E->getInitializedFieldInUnion();
|
|
|
|
LValue FieldLoc = CGF.EmitLValueForFieldInitialization(DestLV, Field);
|
|
if (NumInitElements) {
|
|
// Store the initializer into the field
|
|
EmitInitializationToLValue(E->getInit(0), FieldLoc);
|
|
} else {
|
|
// Default-initialize to null.
|
|
EmitNullInitializationToLValue(FieldLoc);
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
// Here we iterate over the fields; this makes it simpler to both
|
|
// default-initialize fields and skip over unnamed fields.
|
|
for (const auto *field : record->fields()) {
|
|
// We're done once we hit the flexible array member.
|
|
if (field->getType()->isIncompleteArrayType())
|
|
break;
|
|
|
|
// Always skip anonymous bitfields.
|
|
if (field->isUnnamedBitfield())
|
|
continue;
|
|
|
|
// We're done if we reach the end of the explicit initializers, we
|
|
// have a zeroed object, and the rest of the fields are
|
|
// zero-initializable.
|
|
if (curInitIndex == NumInitElements && Dest.isZeroed() &&
|
|
CGF.getTypes().isZeroInitializable(E->getType()))
|
|
break;
|
|
|
|
|
|
LValue LV = CGF.EmitLValueForFieldInitialization(DestLV, field);
|
|
// We never generate write-barries for initialized fields.
|
|
LV.setNonGC(true);
|
|
|
|
if (curInitIndex < NumInitElements) {
|
|
// Store the initializer into the field.
|
|
EmitInitializationToLValue(E->getInit(curInitIndex++), LV);
|
|
} else {
|
|
// We're out of initializers; default-initialize to null
|
|
EmitNullInitializationToLValue(LV);
|
|
}
|
|
|
|
// Push a destructor if necessary.
|
|
// FIXME: if we have an array of structures, all explicitly
|
|
// initialized, we can end up pushing a linear number of cleanups.
|
|
bool pushedCleanup = false;
|
|
if (QualType::DestructionKind dtorKind
|
|
= field->getType().isDestructedType()) {
|
|
assert(LV.isSimple());
|
|
if (CGF.needsEHCleanup(dtorKind)) {
|
|
CGF.pushDestroy(EHCleanup, LV.getAddress(CGF), field->getType(),
|
|
CGF.getDestroyer(dtorKind), false);
|
|
addCleanup(CGF.EHStack.stable_begin());
|
|
pushedCleanup = true;
|
|
}
|
|
}
|
|
|
|
// If the GEP didn't get used because of a dead zero init or something
|
|
// else, clean it up for -O0 builds and general tidiness.
|
|
if (!pushedCleanup && LV.isSimple())
|
|
if (llvm::GetElementPtrInst *GEP =
|
|
dyn_cast<llvm::GetElementPtrInst>(LV.getPointer(CGF)))
|
|
if (GEP->use_empty())
|
|
GEP->eraseFromParent();
|
|
}
|
|
|
|
// Deactivate all the partial cleanups in reverse order, which
|
|
// generally means popping them.
|
|
assert((cleanupDominator || cleanups.empty()) &&
|
|
"Missing cleanupDominator before deactivating cleanup blocks");
|
|
for (unsigned i = cleanups.size(); i != 0; --i)
|
|
CGF.DeactivateCleanupBlock(cleanups[i-1], cleanupDominator);
|
|
|
|
// Destroy the placeholder if we made one.
|
|
if (cleanupDominator)
|
|
cleanupDominator->eraseFromParent();
|
|
}
|
|
|
|
void AggExprEmitter::VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E,
|
|
llvm::Value *outerBegin) {
|
|
// Emit the common subexpression.
|
|
CodeGenFunction::OpaqueValueMapping binding(CGF, E->getCommonExpr());
|
|
|
|
Address destPtr = EnsureSlot(E->getType()).getAddress();
|
|
uint64_t numElements = E->getArraySize().getZExtValue();
|
|
|
|
if (!numElements)
|
|
return;
|
|
|
|
// destPtr is an array*. Construct an elementType* by drilling down a level.
|
|
llvm::Value *zero = llvm::ConstantInt::get(CGF.SizeTy, 0);
|
|
llvm::Value *indices[] = {zero, zero};
|
|
llvm::Value *begin = Builder.CreateInBoundsGEP(destPtr.getPointer(), indices,
|
|
"arrayinit.begin");
|
|
|
|
// Prepare to special-case multidimensional array initialization: we avoid
|
|
// emitting multiple destructor loops in that case.
|
|
if (!outerBegin)
|
|
outerBegin = begin;
|
|
ArrayInitLoopExpr *InnerLoop = dyn_cast<ArrayInitLoopExpr>(E->getSubExpr());
|
|
|
|
QualType elementType =
|
|
CGF.getContext().getAsArrayType(E->getType())->getElementType();
|
|
CharUnits elementSize = CGF.getContext().getTypeSizeInChars(elementType);
|
|
CharUnits elementAlign =
|
|
destPtr.getAlignment().alignmentOfArrayElement(elementSize);
|
|
|
|
llvm::BasicBlock *entryBB = Builder.GetInsertBlock();
|
|
llvm::BasicBlock *bodyBB = CGF.createBasicBlock("arrayinit.body");
|
|
|
|
// Jump into the body.
|
|
CGF.EmitBlock(bodyBB);
|
|
llvm::PHINode *index =
|
|
Builder.CreatePHI(zero->getType(), 2, "arrayinit.index");
|
|
index->addIncoming(zero, entryBB);
|
|
llvm::Value *element = Builder.CreateInBoundsGEP(begin, index);
|
|
|
|
// Prepare for a cleanup.
|
|
QualType::DestructionKind dtorKind = elementType.isDestructedType();
|
|
EHScopeStack::stable_iterator cleanup;
|
|
if (CGF.needsEHCleanup(dtorKind) && !InnerLoop) {
|
|
if (outerBegin->getType() != element->getType())
|
|
outerBegin = Builder.CreateBitCast(outerBegin, element->getType());
|
|
CGF.pushRegularPartialArrayCleanup(outerBegin, element, elementType,
|
|
elementAlign,
|
|
CGF.getDestroyer(dtorKind));
|
|
cleanup = CGF.EHStack.stable_begin();
|
|
} else {
|
|
dtorKind = QualType::DK_none;
|
|
}
|
|
|
|
// Emit the actual filler expression.
|
|
{
|
|
// Temporaries created in an array initialization loop are destroyed
|
|
// at the end of each iteration.
|
|
CodeGenFunction::RunCleanupsScope CleanupsScope(CGF);
|
|
CodeGenFunction::ArrayInitLoopExprScope Scope(CGF, index);
|
|
LValue elementLV =
|
|
CGF.MakeAddrLValue(Address(element, elementAlign), elementType);
|
|
|
|
if (InnerLoop) {
|
|
// If the subexpression is an ArrayInitLoopExpr, share its cleanup.
|
|
auto elementSlot = AggValueSlot::forLValue(
|
|
elementLV, CGF, AggValueSlot::IsDestructed,
|
|
AggValueSlot::DoesNotNeedGCBarriers, AggValueSlot::IsNotAliased,
|
|
AggValueSlot::DoesNotOverlap);
|
|
AggExprEmitter(CGF, elementSlot, false)
|
|
.VisitArrayInitLoopExpr(InnerLoop, outerBegin);
|
|
} else
|
|
EmitInitializationToLValue(E->getSubExpr(), elementLV);
|
|
}
|
|
|
|
// Move on to the next element.
|
|
llvm::Value *nextIndex = Builder.CreateNUWAdd(
|
|
index, llvm::ConstantInt::get(CGF.SizeTy, 1), "arrayinit.next");
|
|
index->addIncoming(nextIndex, Builder.GetInsertBlock());
|
|
|
|
// Leave the loop if we're done.
|
|
llvm::Value *done = Builder.CreateICmpEQ(
|
|
nextIndex, llvm::ConstantInt::get(CGF.SizeTy, numElements),
|
|
"arrayinit.done");
|
|
llvm::BasicBlock *endBB = CGF.createBasicBlock("arrayinit.end");
|
|
Builder.CreateCondBr(done, endBB, bodyBB);
|
|
|
|
CGF.EmitBlock(endBB);
|
|
|
|
// Leave the partial-array cleanup if we entered one.
|
|
if (dtorKind)
|
|
CGF.DeactivateCleanupBlock(cleanup, index);
|
|
}
|
|
|
|
void AggExprEmitter::VisitDesignatedInitUpdateExpr(DesignatedInitUpdateExpr *E) {
|
|
AggValueSlot Dest = EnsureSlot(E->getType());
|
|
|
|
LValue DestLV = CGF.MakeAddrLValue(Dest.getAddress(), E->getType());
|
|
EmitInitializationToLValue(E->getBase(), DestLV);
|
|
VisitInitListExpr(E->getUpdater());
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Entry Points into this File
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
/// GetNumNonZeroBytesInInit - Get an approximate count of the number of
|
|
/// non-zero bytes that will be stored when outputting the initializer for the
|
|
/// specified initializer expression.
|
|
static CharUnits GetNumNonZeroBytesInInit(const Expr *E, CodeGenFunction &CGF) {
|
|
if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(E))
|
|
E = MTE->getSubExpr();
|
|
E = E->IgnoreParenNoopCasts(CGF.getContext());
|
|
|
|
// 0 and 0.0 won't require any non-zero stores!
|
|
if (isSimpleZero(E, CGF)) return CharUnits::Zero();
|
|
|
|
// If this is an initlist expr, sum up the size of sizes of the (present)
|
|
// elements. If this is something weird, assume the whole thing is non-zero.
|
|
const InitListExpr *ILE = dyn_cast<InitListExpr>(E);
|
|
while (ILE && ILE->isTransparent())
|
|
ILE = dyn_cast<InitListExpr>(ILE->getInit(0));
|
|
if (!ILE || !CGF.getTypes().isZeroInitializable(ILE->getType()))
|
|
return CGF.getContext().getTypeSizeInChars(E->getType());
|
|
|
|
// InitListExprs for structs have to be handled carefully. If there are
|
|
// reference members, we need to consider the size of the reference, not the
|
|
// referencee. InitListExprs for unions and arrays can't have references.
|
|
if (const RecordType *RT = E->getType()->getAs<RecordType>()) {
|
|
if (!RT->isUnionType()) {
|
|
RecordDecl *SD = RT->getDecl();
|
|
CharUnits NumNonZeroBytes = CharUnits::Zero();
|
|
|
|
unsigned ILEElement = 0;
|
|
if (auto *CXXRD = dyn_cast<CXXRecordDecl>(SD))
|
|
while (ILEElement != CXXRD->getNumBases())
|
|
NumNonZeroBytes +=
|
|
GetNumNonZeroBytesInInit(ILE->getInit(ILEElement++), CGF);
|
|
for (const auto *Field : SD->fields()) {
|
|
// We're done once we hit the flexible array member or run out of
|
|
// InitListExpr elements.
|
|
if (Field->getType()->isIncompleteArrayType() ||
|
|
ILEElement == ILE->getNumInits())
|
|
break;
|
|
if (Field->isUnnamedBitfield())
|
|
continue;
|
|
|
|
const Expr *E = ILE->getInit(ILEElement++);
|
|
|
|
// Reference values are always non-null and have the width of a pointer.
|
|
if (Field->getType()->isReferenceType())
|
|
NumNonZeroBytes += CGF.getContext().toCharUnitsFromBits(
|
|
CGF.getTarget().getPointerWidth(0));
|
|
else
|
|
NumNonZeroBytes += GetNumNonZeroBytesInInit(E, CGF);
|
|
}
|
|
|
|
return NumNonZeroBytes;
|
|
}
|
|
}
|
|
|
|
// FIXME: This overestimates the number of non-zero bytes for bit-fields.
|
|
CharUnits NumNonZeroBytes = CharUnits::Zero();
|
|
for (unsigned i = 0, e = ILE->getNumInits(); i != e; ++i)
|
|
NumNonZeroBytes += GetNumNonZeroBytesInInit(ILE->getInit(i), CGF);
|
|
return NumNonZeroBytes;
|
|
}
|
|
|
|
/// CheckAggExprForMemSetUse - If the initializer is large and has a lot of
|
|
/// zeros in it, emit a memset and avoid storing the individual zeros.
|
|
///
|
|
static void CheckAggExprForMemSetUse(AggValueSlot &Slot, const Expr *E,
|
|
CodeGenFunction &CGF) {
|
|
// If the slot is already known to be zeroed, nothing to do. Don't mess with
|
|
// volatile stores.
|
|
if (Slot.isZeroed() || Slot.isVolatile() || !Slot.getAddress().isValid())
|
|
return;
|
|
|
|
// C++ objects with a user-declared constructor don't need zero'ing.
|
|
if (CGF.getLangOpts().CPlusPlus)
|
|
if (const RecordType *RT = CGF.getContext()
|
|
.getBaseElementType(E->getType())->getAs<RecordType>()) {
|
|
const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
|
|
if (RD->hasUserDeclaredConstructor())
|
|
return;
|
|
}
|
|
|
|
// If the type is 16-bytes or smaller, prefer individual stores over memset.
|
|
CharUnits Size = Slot.getPreferredSize(CGF.getContext(), E->getType());
|
|
if (Size <= CharUnits::fromQuantity(16))
|
|
return;
|
|
|
|
// Check to see if over 3/4 of the initializer are known to be zero. If so,
|
|
// we prefer to emit memset + individual stores for the rest.
|
|
CharUnits NumNonZeroBytes = GetNumNonZeroBytesInInit(E, CGF);
|
|
if (NumNonZeroBytes*4 > Size)
|
|
return;
|
|
|
|
// Okay, it seems like a good idea to use an initial memset, emit the call.
|
|
llvm::Constant *SizeVal = CGF.Builder.getInt64(Size.getQuantity());
|
|
|
|
Address Loc = Slot.getAddress();
|
|
Loc = CGF.Builder.CreateElementBitCast(Loc, CGF.Int8Ty);
|
|
CGF.Builder.CreateMemSet(Loc, CGF.Builder.getInt8(0), SizeVal, false);
|
|
|
|
// Tell the AggExprEmitter that the slot is known zero.
|
|
Slot.setZeroed();
|
|
}
|
|
|
|
|
|
|
|
|
|
/// 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.
|
|
void CodeGenFunction::EmitAggExpr(const Expr *E, AggValueSlot Slot) {
|
|
assert(E && hasAggregateEvaluationKind(E->getType()) &&
|
|
"Invalid aggregate expression to emit");
|
|
assert((Slot.getAddress().isValid() || Slot.isIgnored()) &&
|
|
"slot has bits but no address");
|
|
|
|
// Optimize the slot if possible.
|
|
CheckAggExprForMemSetUse(Slot, E, *this);
|
|
|
|
AggExprEmitter(*this, Slot, Slot.isIgnored()).Visit(const_cast<Expr*>(E));
|
|
}
|
|
|
|
LValue CodeGenFunction::EmitAggExprToLValue(const Expr *E) {
|
|
assert(hasAggregateEvaluationKind(E->getType()) && "Invalid argument!");
|
|
Address Temp = CreateMemTemp(E->getType());
|
|
LValue LV = MakeAddrLValue(Temp, E->getType());
|
|
EmitAggExpr(E, AggValueSlot::forLValue(
|
|
LV, *this, AggValueSlot::IsNotDestructed,
|
|
AggValueSlot::DoesNotNeedGCBarriers,
|
|
AggValueSlot::IsNotAliased, AggValueSlot::DoesNotOverlap));
|
|
return LV;
|
|
}
|
|
|
|
AggValueSlot::Overlap_t
|
|
CodeGenFunction::getOverlapForFieldInit(const FieldDecl *FD) {
|
|
if (!FD->hasAttr<NoUniqueAddressAttr>() || !FD->getType()->isRecordType())
|
|
return AggValueSlot::DoesNotOverlap;
|
|
|
|
// If the field lies entirely within the enclosing class's nvsize, its tail
|
|
// padding cannot overlap any already-initialized object. (The only subobjects
|
|
// with greater addresses that might already be initialized are vbases.)
|
|
const RecordDecl *ClassRD = FD->getParent();
|
|
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(ClassRD);
|
|
if (Layout.getFieldOffset(FD->getFieldIndex()) +
|
|
getContext().getTypeSize(FD->getType()) <=
|
|
(uint64_t)getContext().toBits(Layout.getNonVirtualSize()))
|
|
return AggValueSlot::DoesNotOverlap;
|
|
|
|
// The tail padding may contain values we need to preserve.
|
|
return AggValueSlot::MayOverlap;
|
|
}
|
|
|
|
AggValueSlot::Overlap_t CodeGenFunction::getOverlapForBaseInit(
|
|
const CXXRecordDecl *RD, const CXXRecordDecl *BaseRD, bool IsVirtual) {
|
|
// If the most-derived object is a field declared with [[no_unique_address]],
|
|
// the tail padding of any virtual base could be reused for other subobjects
|
|
// of that field's class.
|
|
if (IsVirtual)
|
|
return AggValueSlot::MayOverlap;
|
|
|
|
// If the base class is laid out entirely within the nvsize of the derived
|
|
// class, its tail padding cannot yet be initialized, so we can issue
|
|
// stores at the full width of the base class.
|
|
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
|
|
if (Layout.getBaseClassOffset(BaseRD) +
|
|
getContext().getASTRecordLayout(BaseRD).getSize() <=
|
|
Layout.getNonVirtualSize())
|
|
return AggValueSlot::DoesNotOverlap;
|
|
|
|
// The tail padding may contain values we need to preserve.
|
|
return AggValueSlot::MayOverlap;
|
|
}
|
|
|
|
void CodeGenFunction::EmitAggregateCopy(LValue Dest, LValue Src, QualType Ty,
|
|
AggValueSlot::Overlap_t MayOverlap,
|
|
bool isVolatile) {
|
|
assert(!Ty->isAnyComplexType() && "Shouldn't happen for complex");
|
|
|
|
Address DestPtr = Dest.getAddress(*this);
|
|
Address SrcPtr = Src.getAddress(*this);
|
|
|
|
if (getLangOpts().CPlusPlus) {
|
|
if (const RecordType *RT = Ty->getAs<RecordType>()) {
|
|
CXXRecordDecl *Record = cast<CXXRecordDecl>(RT->getDecl());
|
|
assert((Record->hasTrivialCopyConstructor() ||
|
|
Record->hasTrivialCopyAssignment() ||
|
|
Record->hasTrivialMoveConstructor() ||
|
|
Record->hasTrivialMoveAssignment() ||
|
|
Record->isUnion()) &&
|
|
"Trying to aggregate-copy a type without a trivial copy/move "
|
|
"constructor or assignment operator");
|
|
// Ignore empty classes in C++.
|
|
if (Record->isEmpty())
|
|
return;
|
|
}
|
|
}
|
|
|
|
if (getLangOpts().CUDAIsDevice) {
|
|
if (Ty->isCUDADeviceBuiltinSurfaceType()) {
|
|
if (getTargetHooks().emitCUDADeviceBuiltinSurfaceDeviceCopy(*this, Dest,
|
|
Src))
|
|
return;
|
|
} else if (Ty->isCUDADeviceBuiltinTextureType()) {
|
|
if (getTargetHooks().emitCUDADeviceBuiltinTextureDeviceCopy(*this, Dest,
|
|
Src))
|
|
return;
|
|
}
|
|
}
|
|
|
|
// 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.
|
|
|
|
// Get data size info for this aggregate. Don't copy the tail padding if this
|
|
// might be a potentially-overlapping subobject, since the tail padding might
|
|
// be occupied by a different object. Otherwise, copying it is fine.
|
|
TypeInfoChars TypeInfo;
|
|
if (MayOverlap)
|
|
TypeInfo = getContext().getTypeInfoDataSizeInChars(Ty);
|
|
else
|
|
TypeInfo = getContext().getTypeInfoInChars(Ty);
|
|
|
|
llvm::Value *SizeVal = nullptr;
|
|
if (TypeInfo.Width.isZero()) {
|
|
// But note that getTypeInfo returns 0 for a VLA.
|
|
if (auto *VAT = dyn_cast_or_null<VariableArrayType>(
|
|
getContext().getAsArrayType(Ty))) {
|
|
QualType BaseEltTy;
|
|
SizeVal = emitArrayLength(VAT, BaseEltTy, DestPtr);
|
|
TypeInfo = getContext().getTypeInfoInChars(BaseEltTy);
|
|
assert(!TypeInfo.Width.isZero());
|
|
SizeVal = Builder.CreateNUWMul(
|
|
SizeVal,
|
|
llvm::ConstantInt::get(SizeTy, TypeInfo.Width.getQuantity()));
|
|
}
|
|
}
|
|
if (!SizeVal) {
|
|
SizeVal = llvm::ConstantInt::get(SizeTy, TypeInfo.Width.getQuantity());
|
|
}
|
|
|
|
// 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 different call here. We use isVolatile to indicate when
|
|
// either the source or the destination is volatile.
|
|
|
|
DestPtr = Builder.CreateElementBitCast(DestPtr, Int8Ty);
|
|
SrcPtr = Builder.CreateElementBitCast(SrcPtr, Int8Ty);
|
|
|
|
// Don't do any of the memmove_collectable tests if GC isn't set.
|
|
if (CGM.getLangOpts().getGC() == LangOptions::NonGC) {
|
|
// fall through
|
|
} else if (const RecordType *RecordTy = Ty->getAs<RecordType>()) {
|
|
RecordDecl *Record = RecordTy->getDecl();
|
|
if (Record->hasObjectMember()) {
|
|
CGM.getObjCRuntime().EmitGCMemmoveCollectable(*this, DestPtr, SrcPtr,
|
|
SizeVal);
|
|
return;
|
|
}
|
|
} else if (Ty->isArrayType()) {
|
|
QualType BaseType = getContext().getBaseElementType(Ty);
|
|
if (const RecordType *RecordTy = BaseType->getAs<RecordType>()) {
|
|
if (RecordTy->getDecl()->hasObjectMember()) {
|
|
CGM.getObjCRuntime().EmitGCMemmoveCollectable(*this, DestPtr, SrcPtr,
|
|
SizeVal);
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
auto Inst = Builder.CreateMemCpy(DestPtr, SrcPtr, SizeVal, isVolatile);
|
|
|
|
// Determine the metadata to describe the position of any padding in this
|
|
// memcpy, as well as the TBAA tags for the members of the struct, in case
|
|
// the optimizer wishes to expand it in to scalar memory operations.
|
|
if (llvm::MDNode *TBAAStructTag = CGM.getTBAAStructInfo(Ty))
|
|
Inst->setMetadata(llvm::LLVMContext::MD_tbaa_struct, TBAAStructTag);
|
|
|
|
if (CGM.getCodeGenOpts().NewStructPathTBAA) {
|
|
TBAAAccessInfo TBAAInfo = CGM.mergeTBAAInfoForMemoryTransfer(
|
|
Dest.getTBAAInfo(), Src.getTBAAInfo());
|
|
CGM.DecorateInstructionWithTBAA(Inst, TBAAInfo);
|
|
}
|
|
}
|