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GitHub Repository: freebsd/freebsd-src
Path: blob/main/contrib/llvm-project/clang/lib/CodeGen/CGExpr.cpp
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//===--- CGExpr.cpp - Emit LLVM Code from 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 Expr nodes as LLVM code.
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//
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//===----------------------------------------------------------------------===//
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#include "ABIInfoImpl.h"
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#include "CGCUDARuntime.h"
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#include "CGCXXABI.h"
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#include "CGCall.h"
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#include "CGCleanup.h"
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#include "CGDebugInfo.h"
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#include "CGObjCRuntime.h"
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#include "CGOpenMPRuntime.h"
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#include "CGRecordLayout.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/DeclObjC.h"
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#include "clang/AST/NSAPI.h"
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#include "clang/AST/StmtVisitor.h"
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#include "clang/Basic/Builtins.h"
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#include "clang/Basic/CodeGenOptions.h"
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#include "clang/Basic/SourceManager.h"
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#include "llvm/ADT/Hashing.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/ADT/StringExtras.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/Intrinsics.h"
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#include "llvm/IR/IntrinsicsWebAssembly.h"
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#include "llvm/IR/LLVMContext.h"
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#include "llvm/IR/MDBuilder.h"
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#include "llvm/IR/MatrixBuilder.h"
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#include "llvm/Passes/OptimizationLevel.h"
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#include "llvm/Support/ConvertUTF.h"
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#include "llvm/Support/MathExtras.h"
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#include "llvm/Support/Path.h"
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#include "llvm/Support/SaveAndRestore.h"
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#include "llvm/Support/xxhash.h"
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#include "llvm/Transforms/Utils/SanitizerStats.h"
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#include <optional>
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#include <string>
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using namespace clang;
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using namespace CodeGen;
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// Experiment to make sanitizers easier to debug
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static llvm::cl::opt<bool> ClSanitizeDebugDeoptimization(
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"ubsan-unique-traps", llvm::cl::Optional,
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llvm::cl::desc("Deoptimize traps for UBSAN so there is 1 trap per check."));
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// TODO: Introduce frontend options to enabled per sanitizers, similar to
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// `fsanitize-trap`.
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static llvm::cl::opt<bool> ClSanitizeGuardChecks(
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"ubsan-guard-checks", llvm::cl::Optional,
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llvm::cl::desc("Guard UBSAN checks with `llvm.allow.ubsan.check()`."));
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//===--------------------------------------------------------------------===//
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// Miscellaneous Helper Methods
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//===--------------------------------------------------------------------===//
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/// CreateTempAlloca - This creates a alloca and inserts it into the entry
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/// block.
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RawAddress
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CodeGenFunction::CreateTempAllocaWithoutCast(llvm::Type *Ty, CharUnits Align,
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const Twine &Name,
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llvm::Value *ArraySize) {
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auto Alloca = CreateTempAlloca(Ty, Name, ArraySize);
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Alloca->setAlignment(Align.getAsAlign());
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return RawAddress(Alloca, Ty, Align, KnownNonNull);
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}
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/// CreateTempAlloca - This creates a alloca and inserts it into the entry
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/// block. The alloca is casted to default address space if necessary.
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RawAddress CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, CharUnits Align,
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const Twine &Name,
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llvm::Value *ArraySize,
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RawAddress *AllocaAddr) {
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auto Alloca = CreateTempAllocaWithoutCast(Ty, Align, Name, ArraySize);
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if (AllocaAddr)
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*AllocaAddr = Alloca;
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llvm::Value *V = Alloca.getPointer();
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// Alloca always returns a pointer in alloca address space, which may
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// be different from the type defined by the language. For example,
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// in C++ the auto variables are in the default address space. Therefore
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// cast alloca to the default address space when necessary.
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if (getASTAllocaAddressSpace() != LangAS::Default) {
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auto DestAddrSpace = getContext().getTargetAddressSpace(LangAS::Default);
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llvm::IRBuilderBase::InsertPointGuard IPG(Builder);
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// When ArraySize is nullptr, alloca is inserted at AllocaInsertPt,
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// otherwise alloca is inserted at the current insertion point of the
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// builder.
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if (!ArraySize)
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Builder.SetInsertPoint(getPostAllocaInsertPoint());
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V = getTargetHooks().performAddrSpaceCast(
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*this, V, getASTAllocaAddressSpace(), LangAS::Default,
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Ty->getPointerTo(DestAddrSpace), /*non-null*/ true);
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}
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return RawAddress(V, Ty, Align, KnownNonNull);
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}
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/// CreateTempAlloca - This creates an alloca and inserts it into the entry
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/// block if \p ArraySize is nullptr, otherwise inserts it at the current
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/// insertion point of the builder.
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llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty,
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const Twine &Name,
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llvm::Value *ArraySize) {
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llvm::AllocaInst *Alloca;
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if (ArraySize)
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Alloca = Builder.CreateAlloca(Ty, ArraySize, Name);
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else
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Alloca = new llvm::AllocaInst(Ty, CGM.getDataLayout().getAllocaAddrSpace(),
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ArraySize, Name, &*AllocaInsertPt);
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if (Allocas) {
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Allocas->Add(Alloca);
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}
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return Alloca;
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}
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/// CreateDefaultAlignTempAlloca - This creates an alloca with the
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/// default alignment of the corresponding LLVM type, which is *not*
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/// guaranteed to be related in any way to the expected alignment of
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/// an AST type that might have been lowered to Ty.
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RawAddress CodeGenFunction::CreateDefaultAlignTempAlloca(llvm::Type *Ty,
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const Twine &Name) {
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CharUnits Align =
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CharUnits::fromQuantity(CGM.getDataLayout().getPrefTypeAlign(Ty));
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return CreateTempAlloca(Ty, Align, Name);
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}
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RawAddress CodeGenFunction::CreateIRTemp(QualType Ty, const Twine &Name) {
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CharUnits Align = getContext().getTypeAlignInChars(Ty);
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return CreateTempAlloca(ConvertType(Ty), Align, Name);
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}
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RawAddress CodeGenFunction::CreateMemTemp(QualType Ty, const Twine &Name,
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RawAddress *Alloca) {
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// FIXME: Should we prefer the preferred type alignment here?
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return CreateMemTemp(Ty, getContext().getTypeAlignInChars(Ty), Name, Alloca);
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}
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RawAddress CodeGenFunction::CreateMemTemp(QualType Ty, CharUnits Align,
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const Twine &Name,
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RawAddress *Alloca) {
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RawAddress Result = CreateTempAlloca(ConvertTypeForMem(Ty), Align, Name,
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/*ArraySize=*/nullptr, Alloca);
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if (Ty->isConstantMatrixType()) {
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auto *ArrayTy = cast<llvm::ArrayType>(Result.getElementType());
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auto *VectorTy = llvm::FixedVectorType::get(ArrayTy->getElementType(),
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ArrayTy->getNumElements());
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Result = Address(Result.getPointer(), VectorTy, Result.getAlignment(),
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KnownNonNull);
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}
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return Result;
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}
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RawAddress CodeGenFunction::CreateMemTempWithoutCast(QualType Ty,
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CharUnits Align,
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const Twine &Name) {
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return CreateTempAllocaWithoutCast(ConvertTypeForMem(Ty), Align, Name);
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}
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RawAddress CodeGenFunction::CreateMemTempWithoutCast(QualType Ty,
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const Twine &Name) {
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return CreateMemTempWithoutCast(Ty, getContext().getTypeAlignInChars(Ty),
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Name);
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}
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/// EvaluateExprAsBool - Perform the usual unary conversions on the specified
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/// expression and compare the result against zero, returning an Int1Ty value.
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llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
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PGO.setCurrentStmt(E);
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if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) {
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llvm::Value *MemPtr = EmitScalarExpr(E);
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return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT);
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}
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QualType BoolTy = getContext().BoolTy;
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SourceLocation Loc = E->getExprLoc();
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CGFPOptionsRAII FPOptsRAII(*this, E);
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if (!E->getType()->isAnyComplexType())
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return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy, Loc);
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return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(), BoolTy,
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Loc);
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}
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/// EmitIgnoredExpr - Emit code to compute the specified expression,
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/// ignoring the result.
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void CodeGenFunction::EmitIgnoredExpr(const Expr *E) {
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if (E->isPRValue())
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return (void)EmitAnyExpr(E, AggValueSlot::ignored(), true);
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// if this is a bitfield-resulting conditional operator, we can special case
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// emit this. The normal 'EmitLValue' version of this is particularly
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// difficult to codegen for, since creating a single "LValue" for two
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// different sized arguments here is not particularly doable.
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if (const auto *CondOp = dyn_cast<AbstractConditionalOperator>(
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E->IgnoreParenNoopCasts(getContext()))) {
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if (CondOp->getObjectKind() == OK_BitField)
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return EmitIgnoredConditionalOperator(CondOp);
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}
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// Just emit it as an l-value and drop the result.
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EmitLValue(E);
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}
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/// EmitAnyExpr - Emit code to compute the specified expression which
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/// can have any type. The result is returned as an RValue struct.
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/// If this is an aggregate expression, AggSlot indicates where the
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/// result should be returned.
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RValue CodeGenFunction::EmitAnyExpr(const Expr *E,
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AggValueSlot aggSlot,
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bool ignoreResult) {
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switch (getEvaluationKind(E->getType())) {
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case TEK_Scalar:
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return RValue::get(EmitScalarExpr(E, ignoreResult));
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case TEK_Complex:
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return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult));
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case TEK_Aggregate:
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if (!ignoreResult && aggSlot.isIgnored())
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aggSlot = CreateAggTemp(E->getType(), "agg-temp");
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EmitAggExpr(E, aggSlot);
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return aggSlot.asRValue();
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}
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llvm_unreachable("bad evaluation kind");
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}
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/// EmitAnyExprToTemp - Similar to EmitAnyExpr(), however, the result will
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/// always be accessible even if no aggregate location is provided.
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RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) {
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AggValueSlot AggSlot = AggValueSlot::ignored();
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if (hasAggregateEvaluationKind(E->getType()))
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AggSlot = CreateAggTemp(E->getType(), "agg.tmp");
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return EmitAnyExpr(E, AggSlot);
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}
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/// EmitAnyExprToMem - Evaluate an expression into a given memory
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/// location.
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void CodeGenFunction::EmitAnyExprToMem(const Expr *E,
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Address Location,
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Qualifiers Quals,
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bool IsInit) {
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// FIXME: This function should take an LValue as an argument.
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switch (getEvaluationKind(E->getType())) {
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case TEK_Complex:
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EmitComplexExprIntoLValue(E, MakeAddrLValue(Location, E->getType()),
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/*isInit*/ false);
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return;
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case TEK_Aggregate: {
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EmitAggExpr(E, AggValueSlot::forAddr(Location, Quals,
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AggValueSlot::IsDestructed_t(IsInit),
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AggValueSlot::DoesNotNeedGCBarriers,
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AggValueSlot::IsAliased_t(!IsInit),
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AggValueSlot::MayOverlap));
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return;
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}
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case TEK_Scalar: {
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RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false));
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LValue LV = MakeAddrLValue(Location, E->getType());
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EmitStoreThroughLValue(RV, LV);
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return;
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}
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}
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llvm_unreachable("bad evaluation kind");
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}
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static void
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pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M,
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const Expr *E, Address ReferenceTemporary) {
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// Objective-C++ ARC:
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// If we are binding a reference to a temporary that has ownership, we
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// need to perform retain/release operations on the temporary.
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//
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// FIXME: This should be looking at E, not M.
292
if (auto Lifetime = M->getType().getObjCLifetime()) {
293
switch (Lifetime) {
294
case Qualifiers::OCL_None:
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case Qualifiers::OCL_ExplicitNone:
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// Carry on to normal cleanup handling.
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break;
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299
case Qualifiers::OCL_Autoreleasing:
300
// Nothing to do; cleaned up by an autorelease pool.
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return;
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case Qualifiers::OCL_Strong:
304
case Qualifiers::OCL_Weak:
305
switch (StorageDuration Duration = M->getStorageDuration()) {
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case SD_Static:
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// Note: we intentionally do not register a cleanup to release
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// the object on program termination.
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return;
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311
case SD_Thread:
312
// FIXME: We should probably register a cleanup in this case.
313
return;
314
315
case SD_Automatic:
316
case SD_FullExpression:
317
CodeGenFunction::Destroyer *Destroy;
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CleanupKind CleanupKind;
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if (Lifetime == Qualifiers::OCL_Strong) {
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const ValueDecl *VD = M->getExtendingDecl();
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bool Precise = isa_and_nonnull<VarDecl>(VD) &&
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VD->hasAttr<ObjCPreciseLifetimeAttr>();
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CleanupKind = CGF.getARCCleanupKind();
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Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise
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: &CodeGenFunction::destroyARCStrongImprecise;
326
} else {
327
// __weak objects always get EH cleanups; otherwise, exceptions
328
// could cause really nasty crashes instead of mere leaks.
329
CleanupKind = NormalAndEHCleanup;
330
Destroy = &CodeGenFunction::destroyARCWeak;
331
}
332
if (Duration == SD_FullExpression)
333
CGF.pushDestroy(CleanupKind, ReferenceTemporary,
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M->getType(), *Destroy,
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CleanupKind & EHCleanup);
336
else
337
CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary,
338
M->getType(),
339
*Destroy, CleanupKind & EHCleanup);
340
return;
341
342
case SD_Dynamic:
343
llvm_unreachable("temporary cannot have dynamic storage duration");
344
}
345
llvm_unreachable("unknown storage duration");
346
}
347
}
348
349
CXXDestructorDecl *ReferenceTemporaryDtor = nullptr;
350
if (const RecordType *RT =
351
E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
352
// Get the destructor for the reference temporary.
353
auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
354
if (!ClassDecl->hasTrivialDestructor())
355
ReferenceTemporaryDtor = ClassDecl->getDestructor();
356
}
357
358
if (!ReferenceTemporaryDtor)
359
return;
360
361
// Call the destructor for the temporary.
362
switch (M->getStorageDuration()) {
363
case SD_Static:
364
case SD_Thread: {
365
llvm::FunctionCallee CleanupFn;
366
llvm::Constant *CleanupArg;
367
if (E->getType()->isArrayType()) {
368
CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper(
369
ReferenceTemporary, E->getType(),
370
CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions,
371
dyn_cast_or_null<VarDecl>(M->getExtendingDecl()));
372
CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy);
373
} else {
374
CleanupFn = CGF.CGM.getAddrAndTypeOfCXXStructor(
375
GlobalDecl(ReferenceTemporaryDtor, Dtor_Complete));
376
CleanupArg = cast<llvm::Constant>(ReferenceTemporary.emitRawPointer(CGF));
377
}
378
CGF.CGM.getCXXABI().registerGlobalDtor(
379
CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg);
380
break;
381
}
382
383
case SD_FullExpression:
384
CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(),
385
CodeGenFunction::destroyCXXObject,
386
CGF.getLangOpts().Exceptions);
387
break;
388
389
case SD_Automatic:
390
CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup,
391
ReferenceTemporary, E->getType(),
392
CodeGenFunction::destroyCXXObject,
393
CGF.getLangOpts().Exceptions);
394
break;
395
396
case SD_Dynamic:
397
llvm_unreachable("temporary cannot have dynamic storage duration");
398
}
399
}
400
401
static RawAddress createReferenceTemporary(CodeGenFunction &CGF,
402
const MaterializeTemporaryExpr *M,
403
const Expr *Inner,
404
RawAddress *Alloca = nullptr) {
405
auto &TCG = CGF.getTargetHooks();
406
switch (M->getStorageDuration()) {
407
case SD_FullExpression:
408
case SD_Automatic: {
409
// If we have a constant temporary array or record try to promote it into a
410
// constant global under the same rules a normal constant would've been
411
// promoted. This is easier on the optimizer and generally emits fewer
412
// instructions.
413
QualType Ty = Inner->getType();
414
if (CGF.CGM.getCodeGenOpts().MergeAllConstants &&
415
(Ty->isArrayType() || Ty->isRecordType()) &&
416
Ty.isConstantStorage(CGF.getContext(), true, false))
417
if (auto Init = ConstantEmitter(CGF).tryEmitAbstract(Inner, Ty)) {
418
auto AS = CGF.CGM.GetGlobalConstantAddressSpace();
419
auto *GV = new llvm::GlobalVariable(
420
CGF.CGM.getModule(), Init->getType(), /*isConstant=*/true,
421
llvm::GlobalValue::PrivateLinkage, Init, ".ref.tmp", nullptr,
422
llvm::GlobalValue::NotThreadLocal,
423
CGF.getContext().getTargetAddressSpace(AS));
424
CharUnits alignment = CGF.getContext().getTypeAlignInChars(Ty);
425
GV->setAlignment(alignment.getAsAlign());
426
llvm::Constant *C = GV;
427
if (AS != LangAS::Default)
428
C = TCG.performAddrSpaceCast(
429
CGF.CGM, GV, AS, LangAS::Default,
430
GV->getValueType()->getPointerTo(
431
CGF.getContext().getTargetAddressSpace(LangAS::Default)));
432
// FIXME: Should we put the new global into a COMDAT?
433
return RawAddress(C, GV->getValueType(), alignment);
434
}
435
return CGF.CreateMemTemp(Ty, "ref.tmp", Alloca);
436
}
437
case SD_Thread:
438
case SD_Static:
439
return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner);
440
441
case SD_Dynamic:
442
llvm_unreachable("temporary can't have dynamic storage duration");
443
}
444
llvm_unreachable("unknown storage duration");
445
}
446
447
/// Helper method to check if the underlying ABI is AAPCS
448
static bool isAAPCS(const TargetInfo &TargetInfo) {
449
return TargetInfo.getABI().starts_with("aapcs");
450
}
451
452
LValue CodeGenFunction::
453
EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) {
454
const Expr *E = M->getSubExpr();
455
456
assert((!M->getExtendingDecl() || !isa<VarDecl>(M->getExtendingDecl()) ||
457
!cast<VarDecl>(M->getExtendingDecl())->isARCPseudoStrong()) &&
458
"Reference should never be pseudo-strong!");
459
460
// FIXME: ideally this would use EmitAnyExprToMem, however, we cannot do so
461
// as that will cause the lifetime adjustment to be lost for ARC
462
auto ownership = M->getType().getObjCLifetime();
463
if (ownership != Qualifiers::OCL_None &&
464
ownership != Qualifiers::OCL_ExplicitNone) {
465
RawAddress Object = createReferenceTemporary(*this, M, E);
466
if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) {
467
llvm::Type *Ty = ConvertTypeForMem(E->getType());
468
Object = Object.withElementType(Ty);
469
470
// createReferenceTemporary will promote the temporary to a global with a
471
// constant initializer if it can. It can only do this to a value of
472
// ARC-manageable type if the value is global and therefore "immune" to
473
// ref-counting operations. Therefore we have no need to emit either a
474
// dynamic initialization or a cleanup and we can just return the address
475
// of the temporary.
476
if (Var->hasInitializer())
477
return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl);
478
479
Var->setInitializer(CGM.EmitNullConstant(E->getType()));
480
}
481
LValue RefTempDst = MakeAddrLValue(Object, M->getType(),
482
AlignmentSource::Decl);
483
484
switch (getEvaluationKind(E->getType())) {
485
default: llvm_unreachable("expected scalar or aggregate expression");
486
case TEK_Scalar:
487
EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false);
488
break;
489
case TEK_Aggregate: {
490
EmitAggExpr(E, AggValueSlot::forAddr(Object,
491
E->getType().getQualifiers(),
492
AggValueSlot::IsDestructed,
493
AggValueSlot::DoesNotNeedGCBarriers,
494
AggValueSlot::IsNotAliased,
495
AggValueSlot::DoesNotOverlap));
496
break;
497
}
498
}
499
500
pushTemporaryCleanup(*this, M, E, Object);
501
return RefTempDst;
502
}
503
504
SmallVector<const Expr *, 2> CommaLHSs;
505
SmallVector<SubobjectAdjustment, 2> Adjustments;
506
E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
507
508
for (const auto &Ignored : CommaLHSs)
509
EmitIgnoredExpr(Ignored);
510
511
if (const auto *opaque = dyn_cast<OpaqueValueExpr>(E)) {
512
if (opaque->getType()->isRecordType()) {
513
assert(Adjustments.empty());
514
return EmitOpaqueValueLValue(opaque);
515
}
516
}
517
518
// Create and initialize the reference temporary.
519
RawAddress Alloca = Address::invalid();
520
RawAddress Object = createReferenceTemporary(*this, M, E, &Alloca);
521
if (auto *Var = dyn_cast<llvm::GlobalVariable>(
522
Object.getPointer()->stripPointerCasts())) {
523
llvm::Type *TemporaryType = ConvertTypeForMem(E->getType());
524
Object = Object.withElementType(TemporaryType);
525
// If the temporary is a global and has a constant initializer or is a
526
// constant temporary that we promoted to a global, we may have already
527
// initialized it.
528
if (!Var->hasInitializer()) {
529
Var->setInitializer(CGM.EmitNullConstant(E->getType()));
530
EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
531
}
532
} else {
533
switch (M->getStorageDuration()) {
534
case SD_Automatic:
535
if (auto *Size = EmitLifetimeStart(
536
CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()),
537
Alloca.getPointer())) {
538
pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker,
539
Alloca, Size);
540
}
541
break;
542
543
case SD_FullExpression: {
544
if (!ShouldEmitLifetimeMarkers)
545
break;
546
547
// Avoid creating a conditional cleanup just to hold an llvm.lifetime.end
548
// marker. Instead, start the lifetime of a conditional temporary earlier
549
// so that it's unconditional. Don't do this with sanitizers which need
550
// more precise lifetime marks. However when inside an "await.suspend"
551
// block, we should always avoid conditional cleanup because it creates
552
// boolean marker that lives across await_suspend, which can destroy coro
553
// frame.
554
ConditionalEvaluation *OldConditional = nullptr;
555
CGBuilderTy::InsertPoint OldIP;
556
if (isInConditionalBranch() && !E->getType().isDestructedType() &&
557
((!SanOpts.has(SanitizerKind::HWAddress) &&
558
!SanOpts.has(SanitizerKind::Memory) &&
559
!CGM.getCodeGenOpts().SanitizeAddressUseAfterScope) ||
560
inSuspendBlock())) {
561
OldConditional = OutermostConditional;
562
OutermostConditional = nullptr;
563
564
OldIP = Builder.saveIP();
565
llvm::BasicBlock *Block = OldConditional->getStartingBlock();
566
Builder.restoreIP(CGBuilderTy::InsertPoint(
567
Block, llvm::BasicBlock::iterator(Block->back())));
568
}
569
570
if (auto *Size = EmitLifetimeStart(
571
CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()),
572
Alloca.getPointer())) {
573
pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Alloca,
574
Size);
575
}
576
577
if (OldConditional) {
578
OutermostConditional = OldConditional;
579
Builder.restoreIP(OldIP);
580
}
581
break;
582
}
583
584
default:
585
break;
586
}
587
EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
588
}
589
pushTemporaryCleanup(*this, M, E, Object);
590
591
// Perform derived-to-base casts and/or field accesses, to get from the
592
// temporary object we created (and, potentially, for which we extended
593
// the lifetime) to the subobject we're binding the reference to.
594
for (SubobjectAdjustment &Adjustment : llvm::reverse(Adjustments)) {
595
switch (Adjustment.Kind) {
596
case SubobjectAdjustment::DerivedToBaseAdjustment:
597
Object =
598
GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass,
599
Adjustment.DerivedToBase.BasePath->path_begin(),
600
Adjustment.DerivedToBase.BasePath->path_end(),
601
/*NullCheckValue=*/ false, E->getExprLoc());
602
break;
603
604
case SubobjectAdjustment::FieldAdjustment: {
605
LValue LV = MakeAddrLValue(Object, E->getType(), AlignmentSource::Decl);
606
LV = EmitLValueForField(LV, Adjustment.Field);
607
assert(LV.isSimple() &&
608
"materialized temporary field is not a simple lvalue");
609
Object = LV.getAddress();
610
break;
611
}
612
613
case SubobjectAdjustment::MemberPointerAdjustment: {
614
llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS);
615
Object = EmitCXXMemberDataPointerAddress(E, Object, Ptr,
616
Adjustment.Ptr.MPT);
617
break;
618
}
619
}
620
}
621
622
return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl);
623
}
624
625
RValue
626
CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) {
627
// Emit the expression as an lvalue.
628
LValue LV = EmitLValue(E);
629
assert(LV.isSimple());
630
llvm::Value *Value = LV.getPointer(*this);
631
632
if (sanitizePerformTypeCheck() && !E->getType()->isFunctionType()) {
633
// C++11 [dcl.ref]p5 (as amended by core issue 453):
634
// If a glvalue to which a reference is directly bound designates neither
635
// an existing object or function of an appropriate type nor a region of
636
// storage of suitable size and alignment to contain an object of the
637
// reference's type, the behavior is undefined.
638
QualType Ty = E->getType();
639
EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty);
640
}
641
642
return RValue::get(Value);
643
}
644
645
646
/// getAccessedFieldNo - Given an encoded value and a result number, return the
647
/// input field number being accessed.
648
unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
649
const llvm::Constant *Elts) {
650
return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx))
651
->getZExtValue();
652
}
653
654
static llvm::Value *emitHashMix(CGBuilderTy &Builder, llvm::Value *Acc,
655
llvm::Value *Ptr) {
656
llvm::Value *A0 =
657
Builder.CreateMul(Ptr, Builder.getInt64(0xbf58476d1ce4e5b9u));
658
llvm::Value *A1 =
659
Builder.CreateXor(A0, Builder.CreateLShr(A0, Builder.getInt64(31)));
660
return Builder.CreateXor(Acc, A1);
661
}
662
663
bool CodeGenFunction::isNullPointerAllowed(TypeCheckKind TCK) {
664
return TCK == TCK_DowncastPointer || TCK == TCK_Upcast ||
665
TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation;
666
}
667
668
bool CodeGenFunction::isVptrCheckRequired(TypeCheckKind TCK, QualType Ty) {
669
CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
670
return (RD && RD->hasDefinition() && RD->isDynamicClass()) &&
671
(TCK == TCK_MemberAccess || TCK == TCK_MemberCall ||
672
TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference ||
673
TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation);
674
}
675
676
bool CodeGenFunction::sanitizePerformTypeCheck() const {
677
return SanOpts.has(SanitizerKind::Null) ||
678
SanOpts.has(SanitizerKind::Alignment) ||
679
SanOpts.has(SanitizerKind::ObjectSize) ||
680
SanOpts.has(SanitizerKind::Vptr);
681
}
682
683
void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc,
684
llvm::Value *Ptr, QualType Ty,
685
CharUnits Alignment,
686
SanitizerSet SkippedChecks,
687
llvm::Value *ArraySize) {
688
if (!sanitizePerformTypeCheck())
689
return;
690
691
// Don't check pointers outside the default address space. The null check
692
// isn't correct, the object-size check isn't supported by LLVM, and we can't
693
// communicate the addresses to the runtime handler for the vptr check.
694
if (Ptr->getType()->getPointerAddressSpace())
695
return;
696
697
// Don't check pointers to volatile data. The behavior here is implementation-
698
// defined.
699
if (Ty.isVolatileQualified())
700
return;
701
702
SanitizerScope SanScope(this);
703
704
SmallVector<std::pair<llvm::Value *, SanitizerMask>, 3> Checks;
705
llvm::BasicBlock *Done = nullptr;
706
707
// Quickly determine whether we have a pointer to an alloca. It's possible
708
// to skip null checks, and some alignment checks, for these pointers. This
709
// can reduce compile-time significantly.
710
auto PtrToAlloca = dyn_cast<llvm::AllocaInst>(Ptr->stripPointerCasts());
711
712
llvm::Value *True = llvm::ConstantInt::getTrue(getLLVMContext());
713
llvm::Value *IsNonNull = nullptr;
714
bool IsGuaranteedNonNull =
715
SkippedChecks.has(SanitizerKind::Null) || PtrToAlloca;
716
bool AllowNullPointers = isNullPointerAllowed(TCK);
717
if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) &&
718
!IsGuaranteedNonNull) {
719
// The glvalue must not be an empty glvalue.
720
IsNonNull = Builder.CreateIsNotNull(Ptr);
721
722
// The IR builder can constant-fold the null check if the pointer points to
723
// a constant.
724
IsGuaranteedNonNull = IsNonNull == True;
725
726
// Skip the null check if the pointer is known to be non-null.
727
if (!IsGuaranteedNonNull) {
728
if (AllowNullPointers) {
729
// When performing pointer casts, it's OK if the value is null.
730
// Skip the remaining checks in that case.
731
Done = createBasicBlock("null");
732
llvm::BasicBlock *Rest = createBasicBlock("not.null");
733
Builder.CreateCondBr(IsNonNull, Rest, Done);
734
EmitBlock(Rest);
735
} else {
736
Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null));
737
}
738
}
739
}
740
741
if (SanOpts.has(SanitizerKind::ObjectSize) &&
742
!SkippedChecks.has(SanitizerKind::ObjectSize) &&
743
!Ty->isIncompleteType()) {
744
uint64_t TySize = CGM.getMinimumObjectSize(Ty).getQuantity();
745
llvm::Value *Size = llvm::ConstantInt::get(IntPtrTy, TySize);
746
if (ArraySize)
747
Size = Builder.CreateMul(Size, ArraySize);
748
749
// Degenerate case: new X[0] does not need an objectsize check.
750
llvm::Constant *ConstantSize = dyn_cast<llvm::Constant>(Size);
751
if (!ConstantSize || !ConstantSize->isNullValue()) {
752
// The glvalue must refer to a large enough storage region.
753
// FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation
754
// to check this.
755
// FIXME: Get object address space
756
llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
757
llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
758
llvm::Value *Min = Builder.getFalse();
759
llvm::Value *NullIsUnknown = Builder.getFalse();
760
llvm::Value *Dynamic = Builder.getFalse();
761
llvm::Value *LargeEnough = Builder.CreateICmpUGE(
762
Builder.CreateCall(F, {Ptr, Min, NullIsUnknown, Dynamic}), Size);
763
Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize));
764
}
765
}
766
767
llvm::MaybeAlign AlignVal;
768
llvm::Value *PtrAsInt = nullptr;
769
770
if (SanOpts.has(SanitizerKind::Alignment) &&
771
!SkippedChecks.has(SanitizerKind::Alignment)) {
772
AlignVal = Alignment.getAsMaybeAlign();
773
if (!Ty->isIncompleteType() && !AlignVal)
774
AlignVal = CGM.getNaturalTypeAlignment(Ty, nullptr, nullptr,
775
/*ForPointeeType=*/true)
776
.getAsMaybeAlign();
777
778
// The glvalue must be suitably aligned.
779
if (AlignVal && *AlignVal > llvm::Align(1) &&
780
(!PtrToAlloca || PtrToAlloca->getAlign() < *AlignVal)) {
781
PtrAsInt = Builder.CreatePtrToInt(Ptr, IntPtrTy);
782
llvm::Value *Align = Builder.CreateAnd(
783
PtrAsInt, llvm::ConstantInt::get(IntPtrTy, AlignVal->value() - 1));
784
llvm::Value *Aligned =
785
Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0));
786
if (Aligned != True)
787
Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment));
788
}
789
}
790
791
if (Checks.size() > 0) {
792
llvm::Constant *StaticData[] = {
793
EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(Ty),
794
llvm::ConstantInt::get(Int8Ty, AlignVal ? llvm::Log2(*AlignVal) : 1),
795
llvm::ConstantInt::get(Int8Ty, TCK)};
796
EmitCheck(Checks, SanitizerHandler::TypeMismatch, StaticData,
797
PtrAsInt ? PtrAsInt : Ptr);
798
}
799
800
// If possible, check that the vptr indicates that there is a subobject of
801
// type Ty at offset zero within this object.
802
//
803
// C++11 [basic.life]p5,6:
804
// [For storage which does not refer to an object within its lifetime]
805
// The program has undefined behavior if:
806
// -- the [pointer or glvalue] is used to access a non-static data member
807
// or call a non-static member function
808
if (SanOpts.has(SanitizerKind::Vptr) &&
809
!SkippedChecks.has(SanitizerKind::Vptr) && isVptrCheckRequired(TCK, Ty)) {
810
// Ensure that the pointer is non-null before loading it. If there is no
811
// compile-time guarantee, reuse the run-time null check or emit a new one.
812
if (!IsGuaranteedNonNull) {
813
if (!IsNonNull)
814
IsNonNull = Builder.CreateIsNotNull(Ptr);
815
if (!Done)
816
Done = createBasicBlock("vptr.null");
817
llvm::BasicBlock *VptrNotNull = createBasicBlock("vptr.not.null");
818
Builder.CreateCondBr(IsNonNull, VptrNotNull, Done);
819
EmitBlock(VptrNotNull);
820
}
821
822
// Compute a deterministic hash of the mangled name of the type.
823
SmallString<64> MangledName;
824
llvm::raw_svector_ostream Out(MangledName);
825
CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(),
826
Out);
827
828
// Contained in NoSanitizeList based on the mangled type.
829
if (!CGM.getContext().getNoSanitizeList().containsType(SanitizerKind::Vptr,
830
Out.str())) {
831
// Load the vptr, and mix it with TypeHash.
832
llvm::Value *TypeHash =
833
llvm::ConstantInt::get(Int64Ty, xxh3_64bits(Out.str()));
834
835
llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0);
836
Address VPtrAddr(Ptr, IntPtrTy, getPointerAlign());
837
llvm::Value *VPtrVal = GetVTablePtr(VPtrAddr, VPtrTy,
838
Ty->getAsCXXRecordDecl(),
839
VTableAuthMode::UnsafeUbsanStrip);
840
VPtrVal = Builder.CreateBitOrPointerCast(VPtrVal, IntPtrTy);
841
842
llvm::Value *Hash =
843
emitHashMix(Builder, TypeHash, Builder.CreateZExt(VPtrVal, Int64Ty));
844
Hash = Builder.CreateTrunc(Hash, IntPtrTy);
845
846
// Look the hash up in our cache.
847
const int CacheSize = 128;
848
llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize);
849
llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable,
850
"__ubsan_vptr_type_cache");
851
llvm::Value *Slot = Builder.CreateAnd(Hash,
852
llvm::ConstantInt::get(IntPtrTy,
853
CacheSize-1));
854
llvm::Value *Indices[] = { Builder.getInt32(0), Slot };
855
llvm::Value *CacheVal = Builder.CreateAlignedLoad(
856
IntPtrTy, Builder.CreateInBoundsGEP(HashTable, Cache, Indices),
857
getPointerAlign());
858
859
// If the hash isn't in the cache, call a runtime handler to perform the
860
// hard work of checking whether the vptr is for an object of the right
861
// type. This will either fill in the cache and return, or produce a
862
// diagnostic.
863
llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash);
864
llvm::Constant *StaticData[] = {
865
EmitCheckSourceLocation(Loc),
866
EmitCheckTypeDescriptor(Ty),
867
CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()),
868
llvm::ConstantInt::get(Int8Ty, TCK)
869
};
870
llvm::Value *DynamicData[] = { Ptr, Hash };
871
EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr),
872
SanitizerHandler::DynamicTypeCacheMiss, StaticData,
873
DynamicData);
874
}
875
}
876
877
if (Done) {
878
Builder.CreateBr(Done);
879
EmitBlock(Done);
880
}
881
}
882
883
llvm::Value *CodeGenFunction::LoadPassedObjectSize(const Expr *E,
884
QualType EltTy) {
885
ASTContext &C = getContext();
886
uint64_t EltSize = C.getTypeSizeInChars(EltTy).getQuantity();
887
if (!EltSize)
888
return nullptr;
889
890
auto *ArrayDeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts());
891
if (!ArrayDeclRef)
892
return nullptr;
893
894
auto *ParamDecl = dyn_cast<ParmVarDecl>(ArrayDeclRef->getDecl());
895
if (!ParamDecl)
896
return nullptr;
897
898
auto *POSAttr = ParamDecl->getAttr<PassObjectSizeAttr>();
899
if (!POSAttr)
900
return nullptr;
901
902
// Don't load the size if it's a lower bound.
903
int POSType = POSAttr->getType();
904
if (POSType != 0 && POSType != 1)
905
return nullptr;
906
907
// Find the implicit size parameter.
908
auto PassedSizeIt = SizeArguments.find(ParamDecl);
909
if (PassedSizeIt == SizeArguments.end())
910
return nullptr;
911
912
const ImplicitParamDecl *PassedSizeDecl = PassedSizeIt->second;
913
assert(LocalDeclMap.count(PassedSizeDecl) && "Passed size not loadable");
914
Address AddrOfSize = LocalDeclMap.find(PassedSizeDecl)->second;
915
llvm::Value *SizeInBytes = EmitLoadOfScalar(AddrOfSize, /*Volatile=*/false,
916
C.getSizeType(), E->getExprLoc());
917
llvm::Value *SizeOfElement =
918
llvm::ConstantInt::get(SizeInBytes->getType(), EltSize);
919
return Builder.CreateUDiv(SizeInBytes, SizeOfElement);
920
}
921
922
/// If Base is known to point to the start of an array, return the length of
923
/// that array. Return 0 if the length cannot be determined.
924
static llvm::Value *getArrayIndexingBound(CodeGenFunction &CGF,
925
const Expr *Base,
926
QualType &IndexedType,
927
LangOptions::StrictFlexArraysLevelKind
928
StrictFlexArraysLevel) {
929
// For the vector indexing extension, the bound is the number of elements.
930
if (const VectorType *VT = Base->getType()->getAs<VectorType>()) {
931
IndexedType = Base->getType();
932
return CGF.Builder.getInt32(VT->getNumElements());
933
}
934
935
Base = Base->IgnoreParens();
936
937
if (const auto *CE = dyn_cast<CastExpr>(Base)) {
938
if (CE->getCastKind() == CK_ArrayToPointerDecay &&
939
!CE->getSubExpr()->isFlexibleArrayMemberLike(CGF.getContext(),
940
StrictFlexArraysLevel)) {
941
CodeGenFunction::SanitizerScope SanScope(&CGF);
942
943
IndexedType = CE->getSubExpr()->getType();
944
const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe();
945
if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
946
return CGF.Builder.getInt(CAT->getSize());
947
948
if (const auto *VAT = dyn_cast<VariableArrayType>(AT))
949
return CGF.getVLASize(VAT).NumElts;
950
// Ignore pass_object_size here. It's not applicable on decayed pointers.
951
}
952
}
953
954
CodeGenFunction::SanitizerScope SanScope(&CGF);
955
956
QualType EltTy{Base->getType()->getPointeeOrArrayElementType(), 0};
957
if (llvm::Value *POS = CGF.LoadPassedObjectSize(Base, EltTy)) {
958
IndexedType = Base->getType();
959
return POS;
960
}
961
962
return nullptr;
963
}
964
965
namespace {
966
967
/// \p StructAccessBase returns the base \p Expr of a field access. It returns
968
/// either a \p DeclRefExpr, representing the base pointer to the struct, i.e.:
969
///
970
/// p in p-> a.b.c
971
///
972
/// or a \p MemberExpr, if the \p MemberExpr has the \p RecordDecl we're
973
/// looking for:
974
///
975
/// struct s {
976
/// struct s *ptr;
977
/// int count;
978
/// char array[] __attribute__((counted_by(count)));
979
/// };
980
///
981
/// If we have an expression like \p p->ptr->array[index], we want the
982
/// \p MemberExpr for \p p->ptr instead of \p p.
983
class StructAccessBase
984
: public ConstStmtVisitor<StructAccessBase, const Expr *> {
985
const RecordDecl *ExpectedRD;
986
987
bool IsExpectedRecordDecl(const Expr *E) const {
988
QualType Ty = E->getType();
989
if (Ty->isPointerType())
990
Ty = Ty->getPointeeType();
991
return ExpectedRD == Ty->getAsRecordDecl();
992
}
993
994
public:
995
StructAccessBase(const RecordDecl *ExpectedRD) : ExpectedRD(ExpectedRD) {}
996
997
//===--------------------------------------------------------------------===//
998
// Visitor Methods
999
//===--------------------------------------------------------------------===//
1000
1001
// NOTE: If we build C++ support for counted_by, then we'll have to handle
1002
// horrors like this:
1003
//
1004
// struct S {
1005
// int x, y;
1006
// int blah[] __attribute__((counted_by(x)));
1007
// } s;
1008
//
1009
// int foo(int index, int val) {
1010
// int (S::*IHatePMDs)[] = &S::blah;
1011
// (s.*IHatePMDs)[index] = val;
1012
// }
1013
1014
const Expr *Visit(const Expr *E) {
1015
return ConstStmtVisitor<StructAccessBase, const Expr *>::Visit(E);
1016
}
1017
1018
const Expr *VisitStmt(const Stmt *S) { return nullptr; }
1019
1020
// These are the types we expect to return (in order of most to least
1021
// likely):
1022
//
1023
// 1. DeclRefExpr - This is the expression for the base of the structure.
1024
// It's exactly what we want to build an access to the \p counted_by
1025
// field.
1026
// 2. MemberExpr - This is the expression that has the same \p RecordDecl
1027
// as the flexble array member's lexical enclosing \p RecordDecl. This
1028
// allows us to catch things like: "p->p->array"
1029
// 3. CompoundLiteralExpr - This is for people who create something
1030
// heretical like (struct foo has a flexible array member):
1031
//
1032
// (struct foo){ 1, 2 }.blah[idx];
1033
const Expr *VisitDeclRefExpr(const DeclRefExpr *E) {
1034
return IsExpectedRecordDecl(E) ? E : nullptr;
1035
}
1036
const Expr *VisitMemberExpr(const MemberExpr *E) {
1037
if (IsExpectedRecordDecl(E) && E->isArrow())
1038
return E;
1039
const Expr *Res = Visit(E->getBase());
1040
return !Res && IsExpectedRecordDecl(E) ? E : Res;
1041
}
1042
const Expr *VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) {
1043
return IsExpectedRecordDecl(E) ? E : nullptr;
1044
}
1045
const Expr *VisitCallExpr(const CallExpr *E) {
1046
return IsExpectedRecordDecl(E) ? E : nullptr;
1047
}
1048
1049
const Expr *VisitArraySubscriptExpr(const ArraySubscriptExpr *E) {
1050
if (IsExpectedRecordDecl(E))
1051
return E;
1052
return Visit(E->getBase());
1053
}
1054
const Expr *VisitCastExpr(const CastExpr *E) {
1055
if (E->getCastKind() == CK_LValueToRValue)
1056
return IsExpectedRecordDecl(E) ? E : nullptr;
1057
return Visit(E->getSubExpr());
1058
}
1059
const Expr *VisitParenExpr(const ParenExpr *E) {
1060
return Visit(E->getSubExpr());
1061
}
1062
const Expr *VisitUnaryAddrOf(const UnaryOperator *E) {
1063
return Visit(E->getSubExpr());
1064
}
1065
const Expr *VisitUnaryDeref(const UnaryOperator *E) {
1066
return Visit(E->getSubExpr());
1067
}
1068
};
1069
1070
} // end anonymous namespace
1071
1072
using RecIndicesTy =
1073
SmallVector<std::pair<const RecordDecl *, llvm::Value *>, 8>;
1074
1075
static bool getGEPIndicesToField(CodeGenFunction &CGF, const RecordDecl *RD,
1076
const FieldDecl *Field,
1077
RecIndicesTy &Indices) {
1078
const CGRecordLayout &Layout = CGF.CGM.getTypes().getCGRecordLayout(RD);
1079
int64_t FieldNo = -1;
1080
for (const FieldDecl *FD : RD->fields()) {
1081
if (!Layout.containsFieldDecl(FD))
1082
// This could happen if the field has a struct type that's empty. I don't
1083
// know why either.
1084
continue;
1085
1086
FieldNo = Layout.getLLVMFieldNo(FD);
1087
if (FD == Field) {
1088
Indices.emplace_back(std::make_pair(RD, CGF.Builder.getInt32(FieldNo)));
1089
return true;
1090
}
1091
1092
QualType Ty = FD->getType();
1093
if (Ty->isRecordType()) {
1094
if (getGEPIndicesToField(CGF, Ty->getAsRecordDecl(), Field, Indices)) {
1095
if (RD->isUnion())
1096
FieldNo = 0;
1097
Indices.emplace_back(std::make_pair(RD, CGF.Builder.getInt32(FieldNo)));
1098
return true;
1099
}
1100
}
1101
}
1102
1103
return false;
1104
}
1105
1106
/// This method is typically called in contexts where we can't generate
1107
/// side-effects, like in __builtin_dynamic_object_size. When finding
1108
/// expressions, only choose those that have either already been emitted or can
1109
/// be loaded without side-effects.
1110
///
1111
/// - \p FAMDecl: the \p Decl for the flexible array member. It may not be
1112
/// within the top-level struct.
1113
/// - \p CountDecl: must be within the same non-anonymous struct as \p FAMDecl.
1114
llvm::Value *CodeGenFunction::EmitCountedByFieldExpr(
1115
const Expr *Base, const FieldDecl *FAMDecl, const FieldDecl *CountDecl) {
1116
const RecordDecl *RD = CountDecl->getParent()->getOuterLexicalRecordContext();
1117
1118
// Find the base struct expr (i.e. p in p->a.b.c.d).
1119
const Expr *StructBase = StructAccessBase(RD).Visit(Base);
1120
if (!StructBase || StructBase->HasSideEffects(getContext()))
1121
return nullptr;
1122
1123
llvm::Value *Res = nullptr;
1124
if (StructBase->getType()->isPointerType()) {
1125
LValueBaseInfo BaseInfo;
1126
TBAAAccessInfo TBAAInfo;
1127
Address Addr = EmitPointerWithAlignment(StructBase, &BaseInfo, &TBAAInfo);
1128
Res = Addr.emitRawPointer(*this);
1129
} else if (StructBase->isLValue()) {
1130
LValue LV = EmitLValue(StructBase);
1131
Address Addr = LV.getAddress();
1132
Res = Addr.emitRawPointer(*this);
1133
} else {
1134
return nullptr;
1135
}
1136
1137
llvm::Value *Zero = Builder.getInt32(0);
1138
RecIndicesTy Indices;
1139
1140
getGEPIndicesToField(*this, RD, CountDecl, Indices);
1141
1142
for (auto I = Indices.rbegin(), E = Indices.rend(); I != E; ++I)
1143
Res = Builder.CreateInBoundsGEP(
1144
ConvertType(QualType(I->first->getTypeForDecl(), 0)), Res,
1145
{Zero, I->second}, "..counted_by.gep");
1146
1147
return Builder.CreateAlignedLoad(ConvertType(CountDecl->getType()), Res,
1148
getIntAlign(), "..counted_by.load");
1149
}
1150
1151
const FieldDecl *CodeGenFunction::FindCountedByField(const FieldDecl *FD) {
1152
if (!FD)
1153
return nullptr;
1154
1155
const auto *CAT = FD->getType()->getAs<CountAttributedType>();
1156
if (!CAT)
1157
return nullptr;
1158
1159
const auto *CountDRE = cast<DeclRefExpr>(CAT->getCountExpr());
1160
const auto *CountDecl = CountDRE->getDecl();
1161
if (const auto *IFD = dyn_cast<IndirectFieldDecl>(CountDecl))
1162
CountDecl = IFD->getAnonField();
1163
1164
return dyn_cast<FieldDecl>(CountDecl);
1165
}
1166
1167
void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
1168
llvm::Value *Index, QualType IndexType,
1169
bool Accessed) {
1170
assert(SanOpts.has(SanitizerKind::ArrayBounds) &&
1171
"should not be called unless adding bounds checks");
1172
const LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel =
1173
getLangOpts().getStrictFlexArraysLevel();
1174
QualType IndexedType;
1175
llvm::Value *Bound =
1176
getArrayIndexingBound(*this, Base, IndexedType, StrictFlexArraysLevel);
1177
1178
EmitBoundsCheckImpl(E, Bound, Index, IndexType, IndexedType, Accessed);
1179
}
1180
1181
void CodeGenFunction::EmitBoundsCheckImpl(const Expr *E, llvm::Value *Bound,
1182
llvm::Value *Index,
1183
QualType IndexType,
1184
QualType IndexedType, bool Accessed) {
1185
if (!Bound)
1186
return;
1187
1188
SanitizerScope SanScope(this);
1189
1190
bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType();
1191
llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned);
1192
llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false);
1193
1194
llvm::Constant *StaticData[] = {
1195
EmitCheckSourceLocation(E->getExprLoc()),
1196
EmitCheckTypeDescriptor(IndexedType),
1197
EmitCheckTypeDescriptor(IndexType)
1198
};
1199
llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal)
1200
: Builder.CreateICmpULE(IndexVal, BoundVal);
1201
EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds),
1202
SanitizerHandler::OutOfBounds, StaticData, Index);
1203
}
1204
1205
CodeGenFunction::ComplexPairTy CodeGenFunction::
1206
EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
1207
bool isInc, bool isPre) {
1208
ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc());
1209
1210
llvm::Value *NextVal;
1211
if (isa<llvm::IntegerType>(InVal.first->getType())) {
1212
uint64_t AmountVal = isInc ? 1 : -1;
1213
NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
1214
1215
// Add the inc/dec to the real part.
1216
NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
1217
} else {
1218
QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType();
1219
llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
1220
if (!isInc)
1221
FVal.changeSign();
1222
NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
1223
1224
// Add the inc/dec to the real part.
1225
NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
1226
}
1227
1228
ComplexPairTy IncVal(NextVal, InVal.second);
1229
1230
// Store the updated result through the lvalue.
1231
EmitStoreOfComplex(IncVal, LV, /*init*/ false);
1232
if (getLangOpts().OpenMP)
1233
CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this,
1234
E->getSubExpr());
1235
1236
// If this is a postinc, return the value read from memory, otherwise use the
1237
// updated value.
1238
return isPre ? IncVal : InVal;
1239
}
1240
1241
void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E,
1242
CodeGenFunction *CGF) {
1243
// Bind VLAs in the cast type.
1244
if (CGF && E->getType()->isVariablyModifiedType())
1245
CGF->EmitVariablyModifiedType(E->getType());
1246
1247
if (CGDebugInfo *DI = getModuleDebugInfo())
1248
DI->EmitExplicitCastType(E->getType());
1249
}
1250
1251
//===----------------------------------------------------------------------===//
1252
// LValue Expression Emission
1253
//===----------------------------------------------------------------------===//
1254
1255
static Address EmitPointerWithAlignment(const Expr *E, LValueBaseInfo *BaseInfo,
1256
TBAAAccessInfo *TBAAInfo,
1257
KnownNonNull_t IsKnownNonNull,
1258
CodeGenFunction &CGF) {
1259
// We allow this with ObjC object pointers because of fragile ABIs.
1260
assert(E->getType()->isPointerType() ||
1261
E->getType()->isObjCObjectPointerType());
1262
E = E->IgnoreParens();
1263
1264
// Casts:
1265
if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
1266
if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE))
1267
CGF.CGM.EmitExplicitCastExprType(ECE, &CGF);
1268
1269
switch (CE->getCastKind()) {
1270
// Non-converting casts (but not C's implicit conversion from void*).
1271
case CK_BitCast:
1272
case CK_NoOp:
1273
case CK_AddressSpaceConversion:
1274
if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) {
1275
if (PtrTy->getPointeeType()->isVoidType())
1276
break;
1277
1278
LValueBaseInfo InnerBaseInfo;
1279
TBAAAccessInfo InnerTBAAInfo;
1280
Address Addr = CGF.EmitPointerWithAlignment(
1281
CE->getSubExpr(), &InnerBaseInfo, &InnerTBAAInfo, IsKnownNonNull);
1282
if (BaseInfo) *BaseInfo = InnerBaseInfo;
1283
if (TBAAInfo) *TBAAInfo = InnerTBAAInfo;
1284
1285
if (isa<ExplicitCastExpr>(CE)) {
1286
LValueBaseInfo TargetTypeBaseInfo;
1287
TBAAAccessInfo TargetTypeTBAAInfo;
1288
CharUnits Align = CGF.CGM.getNaturalPointeeTypeAlignment(
1289
E->getType(), &TargetTypeBaseInfo, &TargetTypeTBAAInfo);
1290
if (TBAAInfo)
1291
*TBAAInfo =
1292
CGF.CGM.mergeTBAAInfoForCast(*TBAAInfo, TargetTypeTBAAInfo);
1293
// If the source l-value is opaque, honor the alignment of the
1294
// casted-to type.
1295
if (InnerBaseInfo.getAlignmentSource() != AlignmentSource::Decl) {
1296
if (BaseInfo)
1297
BaseInfo->mergeForCast(TargetTypeBaseInfo);
1298
Addr.setAlignment(Align);
1299
}
1300
}
1301
1302
if (CGF.SanOpts.has(SanitizerKind::CFIUnrelatedCast) &&
1303
CE->getCastKind() == CK_BitCast) {
1304
if (auto PT = E->getType()->getAs<PointerType>())
1305
CGF.EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr,
1306
/*MayBeNull=*/true,
1307
CodeGenFunction::CFITCK_UnrelatedCast,
1308
CE->getBeginLoc());
1309
}
1310
1311
llvm::Type *ElemTy =
1312
CGF.ConvertTypeForMem(E->getType()->getPointeeType());
1313
Addr = Addr.withElementType(ElemTy);
1314
if (CE->getCastKind() == CK_AddressSpaceConversion)
1315
Addr = CGF.Builder.CreateAddrSpaceCast(
1316
Addr, CGF.ConvertType(E->getType()), ElemTy);
1317
return CGF.authPointerToPointerCast(Addr, CE->getSubExpr()->getType(),
1318
CE->getType());
1319
}
1320
break;
1321
1322
// Array-to-pointer decay.
1323
case CK_ArrayToPointerDecay:
1324
return CGF.EmitArrayToPointerDecay(CE->getSubExpr(), BaseInfo, TBAAInfo);
1325
1326
// Derived-to-base conversions.
1327
case CK_UncheckedDerivedToBase:
1328
case CK_DerivedToBase: {
1329
// TODO: Support accesses to members of base classes in TBAA. For now, we
1330
// conservatively pretend that the complete object is of the base class
1331
// type.
1332
if (TBAAInfo)
1333
*TBAAInfo = CGF.CGM.getTBAAAccessInfo(E->getType());
1334
Address Addr = CGF.EmitPointerWithAlignment(
1335
CE->getSubExpr(), BaseInfo, nullptr,
1336
(KnownNonNull_t)(IsKnownNonNull ||
1337
CE->getCastKind() == CK_UncheckedDerivedToBase));
1338
auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl();
1339
return CGF.GetAddressOfBaseClass(
1340
Addr, Derived, CE->path_begin(), CE->path_end(),
1341
CGF.ShouldNullCheckClassCastValue(CE), CE->getExprLoc());
1342
}
1343
1344
// TODO: Is there any reason to treat base-to-derived conversions
1345
// specially?
1346
default:
1347
break;
1348
}
1349
}
1350
1351
// Unary &.
1352
if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
1353
if (UO->getOpcode() == UO_AddrOf) {
1354
LValue LV = CGF.EmitLValue(UO->getSubExpr(), IsKnownNonNull);
1355
if (BaseInfo) *BaseInfo = LV.getBaseInfo();
1356
if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo();
1357
return LV.getAddress();
1358
}
1359
}
1360
1361
// std::addressof and variants.
1362
if (auto *Call = dyn_cast<CallExpr>(E)) {
1363
switch (Call->getBuiltinCallee()) {
1364
default:
1365
break;
1366
case Builtin::BIaddressof:
1367
case Builtin::BI__addressof:
1368
case Builtin::BI__builtin_addressof: {
1369
LValue LV = CGF.EmitLValue(Call->getArg(0), IsKnownNonNull);
1370
if (BaseInfo) *BaseInfo = LV.getBaseInfo();
1371
if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo();
1372
return LV.getAddress();
1373
}
1374
}
1375
}
1376
1377
// TODO: conditional operators, comma.
1378
1379
// Otherwise, use the alignment of the type.
1380
return CGF.makeNaturalAddressForPointer(
1381
CGF.EmitScalarExpr(E), E->getType()->getPointeeType(), CharUnits(),
1382
/*ForPointeeType=*/true, BaseInfo, TBAAInfo, IsKnownNonNull);
1383
}
1384
1385
/// EmitPointerWithAlignment - Given an expression of pointer type, try to
1386
/// derive a more accurate bound on the alignment of the pointer.
1387
Address CodeGenFunction::EmitPointerWithAlignment(
1388
const Expr *E, LValueBaseInfo *BaseInfo, TBAAAccessInfo *TBAAInfo,
1389
KnownNonNull_t IsKnownNonNull) {
1390
Address Addr =
1391
::EmitPointerWithAlignment(E, BaseInfo, TBAAInfo, IsKnownNonNull, *this);
1392
if (IsKnownNonNull && !Addr.isKnownNonNull())
1393
Addr.setKnownNonNull();
1394
return Addr;
1395
}
1396
1397
llvm::Value *CodeGenFunction::EmitNonNullRValueCheck(RValue RV, QualType T) {
1398
llvm::Value *V = RV.getScalarVal();
1399
if (auto MPT = T->getAs<MemberPointerType>())
1400
return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, V, MPT);
1401
return Builder.CreateICmpNE(V, llvm::Constant::getNullValue(V->getType()));
1402
}
1403
1404
RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
1405
if (Ty->isVoidType())
1406
return RValue::get(nullptr);
1407
1408
switch (getEvaluationKind(Ty)) {
1409
case TEK_Complex: {
1410
llvm::Type *EltTy =
1411
ConvertType(Ty->castAs<ComplexType>()->getElementType());
1412
llvm::Value *U = llvm::UndefValue::get(EltTy);
1413
return RValue::getComplex(std::make_pair(U, U));
1414
}
1415
1416
// If this is a use of an undefined aggregate type, the aggregate must have an
1417
// identifiable address. Just because the contents of the value are undefined
1418
// doesn't mean that the address can't be taken and compared.
1419
case TEK_Aggregate: {
1420
Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
1421
return RValue::getAggregate(DestPtr);
1422
}
1423
1424
case TEK_Scalar:
1425
return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
1426
}
1427
llvm_unreachable("bad evaluation kind");
1428
}
1429
1430
RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
1431
const char *Name) {
1432
ErrorUnsupported(E, Name);
1433
return GetUndefRValue(E->getType());
1434
}
1435
1436
LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
1437
const char *Name) {
1438
ErrorUnsupported(E, Name);
1439
llvm::Type *ElTy = ConvertType(E->getType());
1440
llvm::Type *Ty = UnqualPtrTy;
1441
return MakeAddrLValue(
1442
Address(llvm::UndefValue::get(Ty), ElTy, CharUnits::One()), E->getType());
1443
}
1444
1445
bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) {
1446
const Expr *Base = Obj;
1447
while (!isa<CXXThisExpr>(Base)) {
1448
// The result of a dynamic_cast can be null.
1449
if (isa<CXXDynamicCastExpr>(Base))
1450
return false;
1451
1452
if (const auto *CE = dyn_cast<CastExpr>(Base)) {
1453
Base = CE->getSubExpr();
1454
} else if (const auto *PE = dyn_cast<ParenExpr>(Base)) {
1455
Base = PE->getSubExpr();
1456
} else if (const auto *UO = dyn_cast<UnaryOperator>(Base)) {
1457
if (UO->getOpcode() == UO_Extension)
1458
Base = UO->getSubExpr();
1459
else
1460
return false;
1461
} else {
1462
return false;
1463
}
1464
}
1465
return true;
1466
}
1467
1468
LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
1469
LValue LV;
1470
if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E))
1471
LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true);
1472
else
1473
LV = EmitLValue(E);
1474
if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) {
1475
SanitizerSet SkippedChecks;
1476
if (const auto *ME = dyn_cast<MemberExpr>(E)) {
1477
bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase());
1478
if (IsBaseCXXThis)
1479
SkippedChecks.set(SanitizerKind::Alignment, true);
1480
if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase()))
1481
SkippedChecks.set(SanitizerKind::Null, true);
1482
}
1483
EmitTypeCheck(TCK, E->getExprLoc(), LV, E->getType(), SkippedChecks);
1484
}
1485
return LV;
1486
}
1487
1488
/// EmitLValue - Emit code to compute a designator that specifies the location
1489
/// of the expression.
1490
///
1491
/// This can return one of two things: a simple address or a bitfield reference.
1492
/// In either case, the LLVM Value* in the LValue structure is guaranteed to be
1493
/// an LLVM pointer type.
1494
///
1495
/// If this returns a bitfield reference, nothing about the pointee type of the
1496
/// LLVM value is known: For example, it may not be a pointer to an integer.
1497
///
1498
/// If this returns a normal address, and if the lvalue's C type is fixed size,
1499
/// this method guarantees that the returned pointer type will point to an LLVM
1500
/// type of the same size of the lvalue's type. If the lvalue has a variable
1501
/// length type, this is not possible.
1502
///
1503
LValue CodeGenFunction::EmitLValue(const Expr *E,
1504
KnownNonNull_t IsKnownNonNull) {
1505
LValue LV = EmitLValueHelper(E, IsKnownNonNull);
1506
if (IsKnownNonNull && !LV.isKnownNonNull())
1507
LV.setKnownNonNull();
1508
return LV;
1509
}
1510
1511
static QualType getConstantExprReferredType(const FullExpr *E,
1512
const ASTContext &Ctx) {
1513
const Expr *SE = E->getSubExpr()->IgnoreImplicit();
1514
if (isa<OpaqueValueExpr>(SE))
1515
return SE->getType();
1516
return cast<CallExpr>(SE)->getCallReturnType(Ctx)->getPointeeType();
1517
}
1518
1519
LValue CodeGenFunction::EmitLValueHelper(const Expr *E,
1520
KnownNonNull_t IsKnownNonNull) {
1521
ApplyDebugLocation DL(*this, E);
1522
switch (E->getStmtClass()) {
1523
default: return EmitUnsupportedLValue(E, "l-value expression");
1524
1525
case Expr::ObjCPropertyRefExprClass:
1526
llvm_unreachable("cannot emit a property reference directly");
1527
1528
case Expr::ObjCSelectorExprClass:
1529
return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
1530
case Expr::ObjCIsaExprClass:
1531
return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
1532
case Expr::BinaryOperatorClass:
1533
return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
1534
case Expr::CompoundAssignOperatorClass: {
1535
QualType Ty = E->getType();
1536
if (const AtomicType *AT = Ty->getAs<AtomicType>())
1537
Ty = AT->getValueType();
1538
if (!Ty->isAnyComplexType())
1539
return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1540
return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1541
}
1542
case Expr::CallExprClass:
1543
case Expr::CXXMemberCallExprClass:
1544
case Expr::CXXOperatorCallExprClass:
1545
case Expr::UserDefinedLiteralClass:
1546
return EmitCallExprLValue(cast<CallExpr>(E));
1547
case Expr::CXXRewrittenBinaryOperatorClass:
1548
return EmitLValue(cast<CXXRewrittenBinaryOperator>(E)->getSemanticForm(),
1549
IsKnownNonNull);
1550
case Expr::VAArgExprClass:
1551
return EmitVAArgExprLValue(cast<VAArgExpr>(E));
1552
case Expr::DeclRefExprClass:
1553
return EmitDeclRefLValue(cast<DeclRefExpr>(E));
1554
case Expr::ConstantExprClass: {
1555
const ConstantExpr *CE = cast<ConstantExpr>(E);
1556
if (llvm::Value *Result = ConstantEmitter(*this).tryEmitConstantExpr(CE)) {
1557
QualType RetType = getConstantExprReferredType(CE, getContext());
1558
return MakeNaturalAlignAddrLValue(Result, RetType);
1559
}
1560
return EmitLValue(cast<ConstantExpr>(E)->getSubExpr(), IsKnownNonNull);
1561
}
1562
case Expr::ParenExprClass:
1563
return EmitLValue(cast<ParenExpr>(E)->getSubExpr(), IsKnownNonNull);
1564
case Expr::GenericSelectionExprClass:
1565
return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr(),
1566
IsKnownNonNull);
1567
case Expr::PredefinedExprClass:
1568
return EmitPredefinedLValue(cast<PredefinedExpr>(E));
1569
case Expr::StringLiteralClass:
1570
return EmitStringLiteralLValue(cast<StringLiteral>(E));
1571
case Expr::ObjCEncodeExprClass:
1572
return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
1573
case Expr::PseudoObjectExprClass:
1574
return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E));
1575
case Expr::InitListExprClass:
1576
return EmitInitListLValue(cast<InitListExpr>(E));
1577
case Expr::CXXTemporaryObjectExprClass:
1578
case Expr::CXXConstructExprClass:
1579
return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
1580
case Expr::CXXBindTemporaryExprClass:
1581
return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
1582
case Expr::CXXUuidofExprClass:
1583
return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E));
1584
case Expr::LambdaExprClass:
1585
return EmitAggExprToLValue(E);
1586
1587
case Expr::ExprWithCleanupsClass: {
1588
const auto *cleanups = cast<ExprWithCleanups>(E);
1589
RunCleanupsScope Scope(*this);
1590
LValue LV = EmitLValue(cleanups->getSubExpr(), IsKnownNonNull);
1591
if (LV.isSimple()) {
1592
// Defend against branches out of gnu statement expressions surrounded by
1593
// cleanups.
1594
Address Addr = LV.getAddress();
1595
llvm::Value *V = Addr.getBasePointer();
1596
Scope.ForceCleanup({&V});
1597
Addr.replaceBasePointer(V);
1598
return LValue::MakeAddr(Addr, LV.getType(), getContext(),
1599
LV.getBaseInfo(), LV.getTBAAInfo());
1600
}
1601
// FIXME: Is it possible to create an ExprWithCleanups that produces a
1602
// bitfield lvalue or some other non-simple lvalue?
1603
return LV;
1604
}
1605
1606
case Expr::CXXDefaultArgExprClass: {
1607
auto *DAE = cast<CXXDefaultArgExpr>(E);
1608
CXXDefaultArgExprScope Scope(*this, DAE);
1609
return EmitLValue(DAE->getExpr(), IsKnownNonNull);
1610
}
1611
case Expr::CXXDefaultInitExprClass: {
1612
auto *DIE = cast<CXXDefaultInitExpr>(E);
1613
CXXDefaultInitExprScope Scope(*this, DIE);
1614
return EmitLValue(DIE->getExpr(), IsKnownNonNull);
1615
}
1616
case Expr::CXXTypeidExprClass:
1617
return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
1618
1619
case Expr::ObjCMessageExprClass:
1620
return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
1621
case Expr::ObjCIvarRefExprClass:
1622
return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
1623
case Expr::StmtExprClass:
1624
return EmitStmtExprLValue(cast<StmtExpr>(E));
1625
case Expr::UnaryOperatorClass:
1626
return EmitUnaryOpLValue(cast<UnaryOperator>(E));
1627
case Expr::ArraySubscriptExprClass:
1628
return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
1629
case Expr::MatrixSubscriptExprClass:
1630
return EmitMatrixSubscriptExpr(cast<MatrixSubscriptExpr>(E));
1631
case Expr::ArraySectionExprClass:
1632
return EmitArraySectionExpr(cast<ArraySectionExpr>(E));
1633
case Expr::ExtVectorElementExprClass:
1634
return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
1635
case Expr::CXXThisExprClass:
1636
return MakeAddrLValue(LoadCXXThisAddress(), E->getType());
1637
case Expr::MemberExprClass:
1638
return EmitMemberExpr(cast<MemberExpr>(E));
1639
case Expr::CompoundLiteralExprClass:
1640
return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
1641
case Expr::ConditionalOperatorClass:
1642
return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
1643
case Expr::BinaryConditionalOperatorClass:
1644
return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
1645
case Expr::ChooseExprClass:
1646
return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(), IsKnownNonNull);
1647
case Expr::OpaqueValueExprClass:
1648
return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
1649
case Expr::SubstNonTypeTemplateParmExprClass:
1650
return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement(),
1651
IsKnownNonNull);
1652
case Expr::ImplicitCastExprClass:
1653
case Expr::CStyleCastExprClass:
1654
case Expr::CXXFunctionalCastExprClass:
1655
case Expr::CXXStaticCastExprClass:
1656
case Expr::CXXDynamicCastExprClass:
1657
case Expr::CXXReinterpretCastExprClass:
1658
case Expr::CXXConstCastExprClass:
1659
case Expr::CXXAddrspaceCastExprClass:
1660
case Expr::ObjCBridgedCastExprClass:
1661
return EmitCastLValue(cast<CastExpr>(E));
1662
1663
case Expr::MaterializeTemporaryExprClass:
1664
return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E));
1665
1666
case Expr::CoawaitExprClass:
1667
return EmitCoawaitLValue(cast<CoawaitExpr>(E));
1668
case Expr::CoyieldExprClass:
1669
return EmitCoyieldLValue(cast<CoyieldExpr>(E));
1670
case Expr::PackIndexingExprClass:
1671
return EmitLValue(cast<PackIndexingExpr>(E)->getSelectedExpr());
1672
}
1673
}
1674
1675
/// Given an object of the given canonical type, can we safely copy a
1676
/// value out of it based on its initializer?
1677
static bool isConstantEmittableObjectType(QualType type) {
1678
assert(type.isCanonical());
1679
assert(!type->isReferenceType());
1680
1681
// Must be const-qualified but non-volatile.
1682
Qualifiers qs = type.getLocalQualifiers();
1683
if (!qs.hasConst() || qs.hasVolatile()) return false;
1684
1685
// Otherwise, all object types satisfy this except C++ classes with
1686
// mutable subobjects or non-trivial copy/destroy behavior.
1687
if (const auto *RT = dyn_cast<RecordType>(type))
1688
if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
1689
if (RD->hasMutableFields() || !RD->isTrivial())
1690
return false;
1691
1692
return true;
1693
}
1694
1695
/// Can we constant-emit a load of a reference to a variable of the
1696
/// given type? This is different from predicates like
1697
/// Decl::mightBeUsableInConstantExpressions because we do want it to apply
1698
/// in situations that don't necessarily satisfy the language's rules
1699
/// for this (e.g. C++'s ODR-use rules). For example, we want to able
1700
/// to do this with const float variables even if those variables
1701
/// aren't marked 'constexpr'.
1702
enum ConstantEmissionKind {
1703
CEK_None,
1704
CEK_AsReferenceOnly,
1705
CEK_AsValueOrReference,
1706
CEK_AsValueOnly
1707
};
1708
static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) {
1709
type = type.getCanonicalType();
1710
if (const auto *ref = dyn_cast<ReferenceType>(type)) {
1711
if (isConstantEmittableObjectType(ref->getPointeeType()))
1712
return CEK_AsValueOrReference;
1713
return CEK_AsReferenceOnly;
1714
}
1715
if (isConstantEmittableObjectType(type))
1716
return CEK_AsValueOnly;
1717
return CEK_None;
1718
}
1719
1720
/// Try to emit a reference to the given value without producing it as
1721
/// an l-value. This is just an optimization, but it avoids us needing
1722
/// to emit global copies of variables if they're named without triggering
1723
/// a formal use in a context where we can't emit a direct reference to them,
1724
/// for instance if a block or lambda or a member of a local class uses a
1725
/// const int variable or constexpr variable from an enclosing function.
1726
CodeGenFunction::ConstantEmission
1727
CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) {
1728
ValueDecl *value = refExpr->getDecl();
1729
1730
// The value needs to be an enum constant or a constant variable.
1731
ConstantEmissionKind CEK;
1732
if (isa<ParmVarDecl>(value)) {
1733
CEK = CEK_None;
1734
} else if (auto *var = dyn_cast<VarDecl>(value)) {
1735
CEK = checkVarTypeForConstantEmission(var->getType());
1736
} else if (isa<EnumConstantDecl>(value)) {
1737
CEK = CEK_AsValueOnly;
1738
} else {
1739
CEK = CEK_None;
1740
}
1741
if (CEK == CEK_None) return ConstantEmission();
1742
1743
Expr::EvalResult result;
1744
bool resultIsReference;
1745
QualType resultType;
1746
1747
// It's best to evaluate all the way as an r-value if that's permitted.
1748
if (CEK != CEK_AsReferenceOnly &&
1749
refExpr->EvaluateAsRValue(result, getContext())) {
1750
resultIsReference = false;
1751
resultType = refExpr->getType();
1752
1753
// Otherwise, try to evaluate as an l-value.
1754
} else if (CEK != CEK_AsValueOnly &&
1755
refExpr->EvaluateAsLValue(result, getContext())) {
1756
resultIsReference = true;
1757
resultType = value->getType();
1758
1759
// Failure.
1760
} else {
1761
return ConstantEmission();
1762
}
1763
1764
// In any case, if the initializer has side-effects, abandon ship.
1765
if (result.HasSideEffects)
1766
return ConstantEmission();
1767
1768
// In CUDA/HIP device compilation, a lambda may capture a reference variable
1769
// referencing a global host variable by copy. In this case the lambda should
1770
// make a copy of the value of the global host variable. The DRE of the
1771
// captured reference variable cannot be emitted as load from the host
1772
// global variable as compile time constant, since the host variable is not
1773
// accessible on device. The DRE of the captured reference variable has to be
1774
// loaded from captures.
1775
if (CGM.getLangOpts().CUDAIsDevice && result.Val.isLValue() &&
1776
refExpr->refersToEnclosingVariableOrCapture()) {
1777
auto *MD = dyn_cast_or_null<CXXMethodDecl>(CurCodeDecl);
1778
if (MD && MD->getParent()->isLambda() &&
1779
MD->getOverloadedOperator() == OO_Call) {
1780
const APValue::LValueBase &base = result.Val.getLValueBase();
1781
if (const ValueDecl *D = base.dyn_cast<const ValueDecl *>()) {
1782
if (const VarDecl *VD = dyn_cast<const VarDecl>(D)) {
1783
if (!VD->hasAttr<CUDADeviceAttr>()) {
1784
return ConstantEmission();
1785
}
1786
}
1787
}
1788
}
1789
}
1790
1791
// Emit as a constant.
1792
auto C = ConstantEmitter(*this).emitAbstract(refExpr->getLocation(),
1793
result.Val, resultType);
1794
1795
// Make sure we emit a debug reference to the global variable.
1796
// This should probably fire even for
1797
if (isa<VarDecl>(value)) {
1798
if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value)))
1799
EmitDeclRefExprDbgValue(refExpr, result.Val);
1800
} else {
1801
assert(isa<EnumConstantDecl>(value));
1802
EmitDeclRefExprDbgValue(refExpr, result.Val);
1803
}
1804
1805
// If we emitted a reference constant, we need to dereference that.
1806
if (resultIsReference)
1807
return ConstantEmission::forReference(C);
1808
1809
return ConstantEmission::forValue(C);
1810
}
1811
1812
static DeclRefExpr *tryToConvertMemberExprToDeclRefExpr(CodeGenFunction &CGF,
1813
const MemberExpr *ME) {
1814
if (auto *VD = dyn_cast<VarDecl>(ME->getMemberDecl())) {
1815
// Try to emit static variable member expressions as DREs.
1816
return DeclRefExpr::Create(
1817
CGF.getContext(), NestedNameSpecifierLoc(), SourceLocation(), VD,
1818
/*RefersToEnclosingVariableOrCapture=*/false, ME->getExprLoc(),
1819
ME->getType(), ME->getValueKind(), nullptr, nullptr, ME->isNonOdrUse());
1820
}
1821
return nullptr;
1822
}
1823
1824
CodeGenFunction::ConstantEmission
1825
CodeGenFunction::tryEmitAsConstant(const MemberExpr *ME) {
1826
if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, ME))
1827
return tryEmitAsConstant(DRE);
1828
return ConstantEmission();
1829
}
1830
1831
llvm::Value *CodeGenFunction::emitScalarConstant(
1832
const CodeGenFunction::ConstantEmission &Constant, Expr *E) {
1833
assert(Constant && "not a constant");
1834
if (Constant.isReference())
1835
return EmitLoadOfLValue(Constant.getReferenceLValue(*this, E),
1836
E->getExprLoc())
1837
.getScalarVal();
1838
return Constant.getValue();
1839
}
1840
1841
llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue,
1842
SourceLocation Loc) {
1843
return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(),
1844
lvalue.getType(), Loc, lvalue.getBaseInfo(),
1845
lvalue.getTBAAInfo(), lvalue.isNontemporal());
1846
}
1847
1848
static bool hasBooleanRepresentation(QualType Ty) {
1849
if (Ty->isBooleanType())
1850
return true;
1851
1852
if (const EnumType *ET = Ty->getAs<EnumType>())
1853
return ET->getDecl()->getIntegerType()->isBooleanType();
1854
1855
if (const AtomicType *AT = Ty->getAs<AtomicType>())
1856
return hasBooleanRepresentation(AT->getValueType());
1857
1858
return false;
1859
}
1860
1861
static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
1862
llvm::APInt &Min, llvm::APInt &End,
1863
bool StrictEnums, bool IsBool) {
1864
const EnumType *ET = Ty->getAs<EnumType>();
1865
bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
1866
ET && !ET->getDecl()->isFixed();
1867
if (!IsBool && !IsRegularCPlusPlusEnum)
1868
return false;
1869
1870
if (IsBool) {
1871
Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0);
1872
End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2);
1873
} else {
1874
const EnumDecl *ED = ET->getDecl();
1875
ED->getValueRange(End, Min);
1876
}
1877
return true;
1878
}
1879
1880
llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
1881
llvm::APInt Min, End;
1882
if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums,
1883
hasBooleanRepresentation(Ty)))
1884
return nullptr;
1885
1886
llvm::MDBuilder MDHelper(getLLVMContext());
1887
return MDHelper.createRange(Min, End);
1888
}
1889
1890
bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
1891
SourceLocation Loc) {
1892
bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool);
1893
bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum);
1894
if (!HasBoolCheck && !HasEnumCheck)
1895
return false;
1896
1897
bool IsBool = hasBooleanRepresentation(Ty) ||
1898
NSAPI(CGM.getContext()).isObjCBOOLType(Ty);
1899
bool NeedsBoolCheck = HasBoolCheck && IsBool;
1900
bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>();
1901
if (!NeedsBoolCheck && !NeedsEnumCheck)
1902
return false;
1903
1904
// Single-bit booleans don't need to be checked. Special-case this to avoid
1905
// a bit width mismatch when handling bitfield values. This is handled by
1906
// EmitFromMemory for the non-bitfield case.
1907
if (IsBool &&
1908
cast<llvm::IntegerType>(Value->getType())->getBitWidth() == 1)
1909
return false;
1910
1911
llvm::APInt Min, End;
1912
if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool))
1913
return true;
1914
1915
auto &Ctx = getLLVMContext();
1916
SanitizerScope SanScope(this);
1917
llvm::Value *Check;
1918
--End;
1919
if (!Min) {
1920
Check = Builder.CreateICmpULE(Value, llvm::ConstantInt::get(Ctx, End));
1921
} else {
1922
llvm::Value *Upper =
1923
Builder.CreateICmpSLE(Value, llvm::ConstantInt::get(Ctx, End));
1924
llvm::Value *Lower =
1925
Builder.CreateICmpSGE(Value, llvm::ConstantInt::get(Ctx, Min));
1926
Check = Builder.CreateAnd(Upper, Lower);
1927
}
1928
llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc),
1929
EmitCheckTypeDescriptor(Ty)};
1930
SanitizerMask Kind =
1931
NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool;
1932
EmitCheck(std::make_pair(Check, Kind), SanitizerHandler::LoadInvalidValue,
1933
StaticArgs, EmitCheckValue(Value));
1934
return true;
1935
}
1936
1937
llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile,
1938
QualType Ty,
1939
SourceLocation Loc,
1940
LValueBaseInfo BaseInfo,
1941
TBAAAccessInfo TBAAInfo,
1942
bool isNontemporal) {
1943
if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr.getBasePointer()))
1944
if (GV->isThreadLocal())
1945
Addr = Addr.withPointer(Builder.CreateThreadLocalAddress(GV),
1946
NotKnownNonNull);
1947
1948
if (const auto *ClangVecTy = Ty->getAs<VectorType>()) {
1949
// Boolean vectors use `iN` as storage type.
1950
if (ClangVecTy->isExtVectorBoolType()) {
1951
llvm::Type *ValTy = ConvertType(Ty);
1952
unsigned ValNumElems =
1953
cast<llvm::FixedVectorType>(ValTy)->getNumElements();
1954
// Load the `iP` storage object (P is the padded vector size).
1955
auto *RawIntV = Builder.CreateLoad(Addr, Volatile, "load_bits");
1956
const auto *RawIntTy = RawIntV->getType();
1957
assert(RawIntTy->isIntegerTy() && "compressed iN storage for bitvectors");
1958
// Bitcast iP --> <P x i1>.
1959
auto *PaddedVecTy = llvm::FixedVectorType::get(
1960
Builder.getInt1Ty(), RawIntTy->getPrimitiveSizeInBits());
1961
llvm::Value *V = Builder.CreateBitCast(RawIntV, PaddedVecTy);
1962
// Shuffle <P x i1> --> <N x i1> (N is the actual bit size).
1963
V = emitBoolVecConversion(V, ValNumElems, "extractvec");
1964
1965
return EmitFromMemory(V, Ty);
1966
}
1967
1968
// Handle vectors of size 3 like size 4 for better performance.
1969
const llvm::Type *EltTy = Addr.getElementType();
1970
const auto *VTy = cast<llvm::FixedVectorType>(EltTy);
1971
1972
if (!CGM.getCodeGenOpts().PreserveVec3Type && VTy->getNumElements() == 3) {
1973
1974
llvm::VectorType *vec4Ty =
1975
llvm::FixedVectorType::get(VTy->getElementType(), 4);
1976
Address Cast = Addr.withElementType(vec4Ty);
1977
// Now load value.
1978
llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4");
1979
1980
// Shuffle vector to get vec3.
1981
V = Builder.CreateShuffleVector(V, ArrayRef<int>{0, 1, 2}, "extractVec");
1982
return EmitFromMemory(V, Ty);
1983
}
1984
}
1985
1986
// Atomic operations have to be done on integral types.
1987
LValue AtomicLValue =
1988
LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1989
if (Ty->isAtomicType() || LValueIsSuitableForInlineAtomic(AtomicLValue)) {
1990
return EmitAtomicLoad(AtomicLValue, Loc).getScalarVal();
1991
}
1992
1993
Addr =
1994
Addr.withElementType(convertTypeForLoadStore(Ty, Addr.getElementType()));
1995
1996
llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile);
1997
if (isNontemporal) {
1998
llvm::MDNode *Node = llvm::MDNode::get(
1999
Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
2000
Load->setMetadata(llvm::LLVMContext::MD_nontemporal, Node);
2001
}
2002
2003
CGM.DecorateInstructionWithTBAA(Load, TBAAInfo);
2004
2005
if (EmitScalarRangeCheck(Load, Ty, Loc)) {
2006
// In order to prevent the optimizer from throwing away the check, don't
2007
// attach range metadata to the load.
2008
} else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
2009
if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty)) {
2010
Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
2011
Load->setMetadata(llvm::LLVMContext::MD_noundef,
2012
llvm::MDNode::get(getLLVMContext(), std::nullopt));
2013
}
2014
2015
return EmitFromMemory(Load, Ty);
2016
}
2017
2018
/// Converts a scalar value from its primary IR type (as returned
2019
/// by ConvertType) to its load/store type (as returned by
2020
/// convertTypeForLoadStore).
2021
llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
2022
if (hasBooleanRepresentation(Ty) || Ty->isBitIntType()) {
2023
llvm::Type *StoreTy = convertTypeForLoadStore(Ty, Value->getType());
2024
bool Signed = Ty->isSignedIntegerOrEnumerationType();
2025
return Builder.CreateIntCast(Value, StoreTy, Signed, "storedv");
2026
}
2027
2028
if (Ty->isExtVectorBoolType()) {
2029
llvm::Type *StoreTy = convertTypeForLoadStore(Ty, Value->getType());
2030
// Expand to the memory bit width.
2031
unsigned MemNumElems = StoreTy->getPrimitiveSizeInBits();
2032
// <N x i1> --> <P x i1>.
2033
Value = emitBoolVecConversion(Value, MemNumElems, "insertvec");
2034
// <P x i1> --> iP.
2035
Value = Builder.CreateBitCast(Value, StoreTy);
2036
}
2037
2038
return Value;
2039
}
2040
2041
/// Converts a scalar value from its load/store type (as returned
2042
/// by convertTypeForLoadStore) to its primary IR type (as returned
2043
/// by ConvertType).
2044
llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
2045
if (Ty->isExtVectorBoolType()) {
2046
const auto *RawIntTy = Value->getType();
2047
// Bitcast iP --> <P x i1>.
2048
auto *PaddedVecTy = llvm::FixedVectorType::get(
2049
Builder.getInt1Ty(), RawIntTy->getPrimitiveSizeInBits());
2050
auto *V = Builder.CreateBitCast(Value, PaddedVecTy);
2051
// Shuffle <P x i1> --> <N x i1> (N is the actual bit size).
2052
llvm::Type *ValTy = ConvertType(Ty);
2053
unsigned ValNumElems = cast<llvm::FixedVectorType>(ValTy)->getNumElements();
2054
return emitBoolVecConversion(V, ValNumElems, "extractvec");
2055
}
2056
2057
if (hasBooleanRepresentation(Ty) || Ty->isBitIntType()) {
2058
llvm::Type *ResTy = ConvertType(Ty);
2059
return Builder.CreateTrunc(Value, ResTy, "loadedv");
2060
}
2061
2062
return Value;
2063
}
2064
2065
// Convert the pointer of \p Addr to a pointer to a vector (the value type of
2066
// MatrixType), if it points to a array (the memory type of MatrixType).
2067
static RawAddress MaybeConvertMatrixAddress(RawAddress Addr,
2068
CodeGenFunction &CGF,
2069
bool IsVector = true) {
2070
auto *ArrayTy = dyn_cast<llvm::ArrayType>(Addr.getElementType());
2071
if (ArrayTy && IsVector) {
2072
auto *VectorTy = llvm::FixedVectorType::get(ArrayTy->getElementType(),
2073
ArrayTy->getNumElements());
2074
2075
return Addr.withElementType(VectorTy);
2076
}
2077
auto *VectorTy = dyn_cast<llvm::VectorType>(Addr.getElementType());
2078
if (VectorTy && !IsVector) {
2079
auto *ArrayTy = llvm::ArrayType::get(
2080
VectorTy->getElementType(),
2081
cast<llvm::FixedVectorType>(VectorTy)->getNumElements());
2082
2083
return Addr.withElementType(ArrayTy);
2084
}
2085
2086
return Addr;
2087
}
2088
2089
// Emit a store of a matrix LValue. This may require casting the original
2090
// pointer to memory address (ArrayType) to a pointer to the value type
2091
// (VectorType).
2092
static void EmitStoreOfMatrixScalar(llvm::Value *value, LValue lvalue,
2093
bool isInit, CodeGenFunction &CGF) {
2094
Address Addr = MaybeConvertMatrixAddress(lvalue.getAddress(), CGF,
2095
value->getType()->isVectorTy());
2096
CGF.EmitStoreOfScalar(value, Addr, lvalue.isVolatile(), lvalue.getType(),
2097
lvalue.getBaseInfo(), lvalue.getTBAAInfo(), isInit,
2098
lvalue.isNontemporal());
2099
}
2100
2101
void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr,
2102
bool Volatile, QualType Ty,
2103
LValueBaseInfo BaseInfo,
2104
TBAAAccessInfo TBAAInfo,
2105
bool isInit, bool isNontemporal) {
2106
if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr.getBasePointer()))
2107
if (GV->isThreadLocal())
2108
Addr = Addr.withPointer(Builder.CreateThreadLocalAddress(GV),
2109
NotKnownNonNull);
2110
2111
llvm::Type *SrcTy = Value->getType();
2112
if (const auto *ClangVecTy = Ty->getAs<VectorType>()) {
2113
auto *VecTy = dyn_cast<llvm::FixedVectorType>(SrcTy);
2114
if (!CGM.getCodeGenOpts().PreserveVec3Type) {
2115
// Handle vec3 special.
2116
if (VecTy && !ClangVecTy->isExtVectorBoolType() &&
2117
cast<llvm::FixedVectorType>(VecTy)->getNumElements() == 3) {
2118
// Our source is a vec3, do a shuffle vector to make it a vec4.
2119
Value = Builder.CreateShuffleVector(Value, ArrayRef<int>{0, 1, 2, -1},
2120
"extractVec");
2121
SrcTy = llvm::FixedVectorType::get(VecTy->getElementType(), 4);
2122
}
2123
if (Addr.getElementType() != SrcTy) {
2124
Addr = Addr.withElementType(SrcTy);
2125
}
2126
}
2127
}
2128
2129
Value = EmitToMemory(Value, Ty);
2130
2131
LValue AtomicLValue =
2132
LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
2133
if (Ty->isAtomicType() ||
2134
(!isInit && LValueIsSuitableForInlineAtomic(AtomicLValue))) {
2135
EmitAtomicStore(RValue::get(Value), AtomicLValue, isInit);
2136
return;
2137
}
2138
2139
llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
2140
if (isNontemporal) {
2141
llvm::MDNode *Node =
2142
llvm::MDNode::get(Store->getContext(),
2143
llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
2144
Store->setMetadata(llvm::LLVMContext::MD_nontemporal, Node);
2145
}
2146
2147
CGM.DecorateInstructionWithTBAA(Store, TBAAInfo);
2148
}
2149
2150
void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue,
2151
bool isInit) {
2152
if (lvalue.getType()->isConstantMatrixType()) {
2153
EmitStoreOfMatrixScalar(value, lvalue, isInit, *this);
2154
return;
2155
}
2156
2157
EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(),
2158
lvalue.getType(), lvalue.getBaseInfo(),
2159
lvalue.getTBAAInfo(), isInit, lvalue.isNontemporal());
2160
}
2161
2162
// Emit a load of a LValue of matrix type. This may require casting the pointer
2163
// to memory address (ArrayType) to a pointer to the value type (VectorType).
2164
static RValue EmitLoadOfMatrixLValue(LValue LV, SourceLocation Loc,
2165
CodeGenFunction &CGF) {
2166
assert(LV.getType()->isConstantMatrixType());
2167
Address Addr = MaybeConvertMatrixAddress(LV.getAddress(), CGF);
2168
LV.setAddress(Addr);
2169
return RValue::get(CGF.EmitLoadOfScalar(LV, Loc));
2170
}
2171
2172
RValue CodeGenFunction::EmitLoadOfAnyValue(LValue LV, AggValueSlot Slot,
2173
SourceLocation Loc) {
2174
QualType Ty = LV.getType();
2175
switch (getEvaluationKind(Ty)) {
2176
case TEK_Scalar:
2177
return EmitLoadOfLValue(LV, Loc);
2178
case TEK_Complex:
2179
return RValue::getComplex(EmitLoadOfComplex(LV, Loc));
2180
case TEK_Aggregate:
2181
EmitAggFinalDestCopy(Ty, Slot, LV, EVK_NonRValue);
2182
return Slot.asRValue();
2183
}
2184
llvm_unreachable("bad evaluation kind");
2185
}
2186
2187
/// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
2188
/// method emits the address of the lvalue, then loads the result as an rvalue,
2189
/// returning the rvalue.
2190
RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
2191
if (LV.isObjCWeak()) {
2192
// load of a __weak object.
2193
Address AddrWeakObj = LV.getAddress();
2194
return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
2195
AddrWeakObj));
2196
}
2197
if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
2198
// In MRC mode, we do a load+autorelease.
2199
if (!getLangOpts().ObjCAutoRefCount) {
2200
return RValue::get(EmitARCLoadWeak(LV.getAddress()));
2201
}
2202
2203
// In ARC mode, we load retained and then consume the value.
2204
llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress());
2205
Object = EmitObjCConsumeObject(LV.getType(), Object);
2206
return RValue::get(Object);
2207
}
2208
2209
if (LV.isSimple()) {
2210
assert(!LV.getType()->isFunctionType());
2211
2212
if (LV.getType()->isConstantMatrixType())
2213
return EmitLoadOfMatrixLValue(LV, Loc, *this);
2214
2215
// Everything needs a load.
2216
return RValue::get(EmitLoadOfScalar(LV, Loc));
2217
}
2218
2219
if (LV.isVectorElt()) {
2220
llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(),
2221
LV.isVolatileQualified());
2222
return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(),
2223
"vecext"));
2224
}
2225
2226
// If this is a reference to a subset of the elements of a vector, either
2227
// shuffle the input or extract/insert them as appropriate.
2228
if (LV.isExtVectorElt()) {
2229
return EmitLoadOfExtVectorElementLValue(LV);
2230
}
2231
2232
// Global Register variables always invoke intrinsics
2233
if (LV.isGlobalReg())
2234
return EmitLoadOfGlobalRegLValue(LV);
2235
2236
if (LV.isMatrixElt()) {
2237
llvm::Value *Idx = LV.getMatrixIdx();
2238
if (CGM.getCodeGenOpts().OptimizationLevel > 0) {
2239
const auto *const MatTy = LV.getType()->castAs<ConstantMatrixType>();
2240
llvm::MatrixBuilder MB(Builder);
2241
MB.CreateIndexAssumption(Idx, MatTy->getNumElementsFlattened());
2242
}
2243
llvm::LoadInst *Load =
2244
Builder.CreateLoad(LV.getMatrixAddress(), LV.isVolatileQualified());
2245
return RValue::get(Builder.CreateExtractElement(Load, Idx, "matrixext"));
2246
}
2247
2248
assert(LV.isBitField() && "Unknown LValue type!");
2249
return EmitLoadOfBitfieldLValue(LV, Loc);
2250
}
2251
2252
RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
2253
SourceLocation Loc) {
2254
const CGBitFieldInfo &Info = LV.getBitFieldInfo();
2255
2256
// Get the output type.
2257
llvm::Type *ResLTy = ConvertType(LV.getType());
2258
2259
Address Ptr = LV.getBitFieldAddress();
2260
llvm::Value *Val =
2261
Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load");
2262
2263
bool UseVolatile = LV.isVolatileQualified() &&
2264
Info.VolatileStorageSize != 0 && isAAPCS(CGM.getTarget());
2265
const unsigned Offset = UseVolatile ? Info.VolatileOffset : Info.Offset;
2266
const unsigned StorageSize =
2267
UseVolatile ? Info.VolatileStorageSize : Info.StorageSize;
2268
if (Info.IsSigned) {
2269
assert(static_cast<unsigned>(Offset + Info.Size) <= StorageSize);
2270
unsigned HighBits = StorageSize - Offset - Info.Size;
2271
if (HighBits)
2272
Val = Builder.CreateShl(Val, HighBits, "bf.shl");
2273
if (Offset + HighBits)
2274
Val = Builder.CreateAShr(Val, Offset + HighBits, "bf.ashr");
2275
} else {
2276
if (Offset)
2277
Val = Builder.CreateLShr(Val, Offset, "bf.lshr");
2278
if (static_cast<unsigned>(Offset) + Info.Size < StorageSize)
2279
Val = Builder.CreateAnd(
2280
Val, llvm::APInt::getLowBitsSet(StorageSize, Info.Size), "bf.clear");
2281
}
2282
Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast");
2283
EmitScalarRangeCheck(Val, LV.getType(), Loc);
2284
return RValue::get(Val);
2285
}
2286
2287
// If this is a reference to a subset of the elements of a vector, create an
2288
// appropriate shufflevector.
2289
RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) {
2290
llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(),
2291
LV.isVolatileQualified());
2292
2293
// HLSL allows treating scalars as one-element vectors. Converting the scalar
2294
// IR value to a vector here allows the rest of codegen to behave as normal.
2295
if (getLangOpts().HLSL && !Vec->getType()->isVectorTy()) {
2296
llvm::Type *DstTy = llvm::FixedVectorType::get(Vec->getType(), 1);
2297
llvm::Value *Zero = llvm::Constant::getNullValue(CGM.Int64Ty);
2298
Vec = Builder.CreateInsertElement(DstTy, Vec, Zero, "cast.splat");
2299
}
2300
2301
const llvm::Constant *Elts = LV.getExtVectorElts();
2302
2303
// If the result of the expression is a non-vector type, we must be extracting
2304
// a single element. Just codegen as an extractelement.
2305
const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
2306
if (!ExprVT) {
2307
unsigned InIdx = getAccessedFieldNo(0, Elts);
2308
llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
2309
return RValue::get(Builder.CreateExtractElement(Vec, Elt));
2310
}
2311
2312
// Always use shuffle vector to try to retain the original program structure
2313
unsigned NumResultElts = ExprVT->getNumElements();
2314
2315
SmallVector<int, 4> Mask;
2316
for (unsigned i = 0; i != NumResultElts; ++i)
2317
Mask.push_back(getAccessedFieldNo(i, Elts));
2318
2319
Vec = Builder.CreateShuffleVector(Vec, Mask);
2320
return RValue::get(Vec);
2321
}
2322
2323
/// Generates lvalue for partial ext_vector access.
2324
Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) {
2325
Address VectorAddress = LV.getExtVectorAddress();
2326
QualType EQT = LV.getType()->castAs<VectorType>()->getElementType();
2327
llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT);
2328
2329
Address CastToPointerElement = VectorAddress.withElementType(VectorElementTy);
2330
2331
const llvm::Constant *Elts = LV.getExtVectorElts();
2332
unsigned ix = getAccessedFieldNo(0, Elts);
2333
2334
Address VectorBasePtrPlusIx =
2335
Builder.CreateConstInBoundsGEP(CastToPointerElement, ix,
2336
"vector.elt");
2337
2338
return VectorBasePtrPlusIx;
2339
}
2340
2341
/// Load of global gamed gegisters are always calls to intrinsics.
2342
RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) {
2343
assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) &&
2344
"Bad type for register variable");
2345
llvm::MDNode *RegName = cast<llvm::MDNode>(
2346
cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata());
2347
2348
// We accept integer and pointer types only
2349
llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType());
2350
llvm::Type *Ty = OrigTy;
2351
if (OrigTy->isPointerTy())
2352
Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
2353
llvm::Type *Types[] = { Ty };
2354
2355
llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types);
2356
llvm::Value *Call = Builder.CreateCall(
2357
F, llvm::MetadataAsValue::get(Ty->getContext(), RegName));
2358
if (OrigTy->isPointerTy())
2359
Call = Builder.CreateIntToPtr(Call, OrigTy);
2360
return RValue::get(Call);
2361
}
2362
2363
/// EmitStoreThroughLValue - Store the specified rvalue into the specified
2364
/// lvalue, where both are guaranteed to the have the same type, and that type
2365
/// is 'Ty'.
2366
void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
2367
bool isInit) {
2368
if (!Dst.isSimple()) {
2369
if (Dst.isVectorElt()) {
2370
// Read/modify/write the vector, inserting the new element.
2371
llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(),
2372
Dst.isVolatileQualified());
2373
auto *IRStoreTy = dyn_cast<llvm::IntegerType>(Vec->getType());
2374
if (IRStoreTy) {
2375
auto *IRVecTy = llvm::FixedVectorType::get(
2376
Builder.getInt1Ty(), IRStoreTy->getPrimitiveSizeInBits());
2377
Vec = Builder.CreateBitCast(Vec, IRVecTy);
2378
// iN --> <N x i1>.
2379
}
2380
Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
2381
Dst.getVectorIdx(), "vecins");
2382
if (IRStoreTy) {
2383
// <N x i1> --> <iN>.
2384
Vec = Builder.CreateBitCast(Vec, IRStoreTy);
2385
}
2386
Builder.CreateStore(Vec, Dst.getVectorAddress(),
2387
Dst.isVolatileQualified());
2388
return;
2389
}
2390
2391
// If this is an update of extended vector elements, insert them as
2392
// appropriate.
2393
if (Dst.isExtVectorElt())
2394
return EmitStoreThroughExtVectorComponentLValue(Src, Dst);
2395
2396
if (Dst.isGlobalReg())
2397
return EmitStoreThroughGlobalRegLValue(Src, Dst);
2398
2399
if (Dst.isMatrixElt()) {
2400
llvm::Value *Idx = Dst.getMatrixIdx();
2401
if (CGM.getCodeGenOpts().OptimizationLevel > 0) {
2402
const auto *const MatTy = Dst.getType()->castAs<ConstantMatrixType>();
2403
llvm::MatrixBuilder MB(Builder);
2404
MB.CreateIndexAssumption(Idx, MatTy->getNumElementsFlattened());
2405
}
2406
llvm::Instruction *Load = Builder.CreateLoad(Dst.getMatrixAddress());
2407
llvm::Value *Vec =
2408
Builder.CreateInsertElement(Load, Src.getScalarVal(), Idx, "matins");
2409
Builder.CreateStore(Vec, Dst.getMatrixAddress(),
2410
Dst.isVolatileQualified());
2411
return;
2412
}
2413
2414
assert(Dst.isBitField() && "Unknown LValue type");
2415
return EmitStoreThroughBitfieldLValue(Src, Dst);
2416
}
2417
2418
// There's special magic for assigning into an ARC-qualified l-value.
2419
if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) {
2420
switch (Lifetime) {
2421
case Qualifiers::OCL_None:
2422
llvm_unreachable("present but none");
2423
2424
case Qualifiers::OCL_ExplicitNone:
2425
// nothing special
2426
break;
2427
2428
case Qualifiers::OCL_Strong:
2429
if (isInit) {
2430
Src = RValue::get(EmitARCRetain(Dst.getType(), Src.getScalarVal()));
2431
break;
2432
}
2433
EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true);
2434
return;
2435
2436
case Qualifiers::OCL_Weak:
2437
if (isInit)
2438
// Initialize and then skip the primitive store.
2439
EmitARCInitWeak(Dst.getAddress(), Src.getScalarVal());
2440
else
2441
EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(),
2442
/*ignore*/ true);
2443
return;
2444
2445
case Qualifiers::OCL_Autoreleasing:
2446
Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(),
2447
Src.getScalarVal()));
2448
// fall into the normal path
2449
break;
2450
}
2451
}
2452
2453
if (Dst.isObjCWeak() && !Dst.isNonGC()) {
2454
// load of a __weak object.
2455
Address LvalueDst = Dst.getAddress();
2456
llvm::Value *src = Src.getScalarVal();
2457
CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
2458
return;
2459
}
2460
2461
if (Dst.isObjCStrong() && !Dst.isNonGC()) {
2462
// load of a __strong object.
2463
Address LvalueDst = Dst.getAddress();
2464
llvm::Value *src = Src.getScalarVal();
2465
if (Dst.isObjCIvar()) {
2466
assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
2467
llvm::Type *ResultType = IntPtrTy;
2468
Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp());
2469
llvm::Value *RHS = dst.emitRawPointer(*this);
2470
RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
2471
llvm::Value *LHS = Builder.CreatePtrToInt(LvalueDst.emitRawPointer(*this),
2472
ResultType, "sub.ptr.lhs.cast");
2473
llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
2474
CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst, BytesBetween);
2475
} else if (Dst.isGlobalObjCRef()) {
2476
CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
2477
Dst.isThreadLocalRef());
2478
}
2479
else
2480
CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
2481
return;
2482
}
2483
2484
assert(Src.isScalar() && "Can't emit an agg store with this method");
2485
EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit);
2486
}
2487
2488
void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
2489
llvm::Value **Result) {
2490
const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
2491
llvm::Type *ResLTy = convertTypeForLoadStore(Dst.getType());
2492
Address Ptr = Dst.getBitFieldAddress();
2493
2494
// Get the source value, truncated to the width of the bit-field.
2495
llvm::Value *SrcVal = Src.getScalarVal();
2496
2497
// Cast the source to the storage type and shift it into place.
2498
SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(),
2499
/*isSigned=*/false);
2500
llvm::Value *MaskedVal = SrcVal;
2501
2502
const bool UseVolatile =
2503
CGM.getCodeGenOpts().AAPCSBitfieldWidth && Dst.isVolatileQualified() &&
2504
Info.VolatileStorageSize != 0 && isAAPCS(CGM.getTarget());
2505
const unsigned StorageSize =
2506
UseVolatile ? Info.VolatileStorageSize : Info.StorageSize;
2507
const unsigned Offset = UseVolatile ? Info.VolatileOffset : Info.Offset;
2508
// See if there are other bits in the bitfield's storage we'll need to load
2509
// and mask together with source before storing.
2510
if (StorageSize != Info.Size) {
2511
assert(StorageSize > Info.Size && "Invalid bitfield size.");
2512
llvm::Value *Val =
2513
Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load");
2514
2515
// Mask the source value as needed.
2516
if (!hasBooleanRepresentation(Dst.getType()))
2517
SrcVal = Builder.CreateAnd(
2518
SrcVal, llvm::APInt::getLowBitsSet(StorageSize, Info.Size),
2519
"bf.value");
2520
MaskedVal = SrcVal;
2521
if (Offset)
2522
SrcVal = Builder.CreateShl(SrcVal, Offset, "bf.shl");
2523
2524
// Mask out the original value.
2525
Val = Builder.CreateAnd(
2526
Val, ~llvm::APInt::getBitsSet(StorageSize, Offset, Offset + Info.Size),
2527
"bf.clear");
2528
2529
// Or together the unchanged values and the source value.
2530
SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set");
2531
} else {
2532
assert(Offset == 0);
2533
// According to the AACPS:
2534
// When a volatile bit-field is written, and its container does not overlap
2535
// with any non-bit-field member, its container must be read exactly once
2536
// and written exactly once using the access width appropriate to the type
2537
// of the container. The two accesses are not atomic.
2538
if (Dst.isVolatileQualified() && isAAPCS(CGM.getTarget()) &&
2539
CGM.getCodeGenOpts().ForceAAPCSBitfieldLoad)
2540
Builder.CreateLoad(Ptr, true, "bf.load");
2541
}
2542
2543
// Write the new value back out.
2544
Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified());
2545
2546
// Return the new value of the bit-field, if requested.
2547
if (Result) {
2548
llvm::Value *ResultVal = MaskedVal;
2549
2550
// Sign extend the value if needed.
2551
if (Info.IsSigned) {
2552
assert(Info.Size <= StorageSize);
2553
unsigned HighBits = StorageSize - Info.Size;
2554
if (HighBits) {
2555
ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl");
2556
ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr");
2557
}
2558
}
2559
2560
ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned,
2561
"bf.result.cast");
2562
*Result = EmitFromMemory(ResultVal, Dst.getType());
2563
}
2564
}
2565
2566
void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
2567
LValue Dst) {
2568
// HLSL allows storing to scalar values through ExtVector component LValues.
2569
// To support this we need to handle the case where the destination address is
2570
// a scalar.
2571
Address DstAddr = Dst.getExtVectorAddress();
2572
if (!DstAddr.getElementType()->isVectorTy()) {
2573
assert(!Dst.getType()->isVectorType() &&
2574
"this should only occur for non-vector l-values");
2575
Builder.CreateStore(Src.getScalarVal(), DstAddr, Dst.isVolatileQualified());
2576
return;
2577
}
2578
2579
// This access turns into a read/modify/write of the vector. Load the input
2580
// value now.
2581
llvm::Value *Vec = Builder.CreateLoad(DstAddr, Dst.isVolatileQualified());
2582
const llvm::Constant *Elts = Dst.getExtVectorElts();
2583
2584
llvm::Value *SrcVal = Src.getScalarVal();
2585
2586
if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) {
2587
unsigned NumSrcElts = VTy->getNumElements();
2588
unsigned NumDstElts =
2589
cast<llvm::FixedVectorType>(Vec->getType())->getNumElements();
2590
if (NumDstElts == NumSrcElts) {
2591
// Use shuffle vector is the src and destination are the same number of
2592
// elements and restore the vector mask since it is on the side it will be
2593
// stored.
2594
SmallVector<int, 4> Mask(NumDstElts);
2595
for (unsigned i = 0; i != NumSrcElts; ++i)
2596
Mask[getAccessedFieldNo(i, Elts)] = i;
2597
2598
Vec = Builder.CreateShuffleVector(SrcVal, Mask);
2599
} else if (NumDstElts > NumSrcElts) {
2600
// Extended the source vector to the same length and then shuffle it
2601
// into the destination.
2602
// FIXME: since we're shuffling with undef, can we just use the indices
2603
// into that? This could be simpler.
2604
SmallVector<int, 4> ExtMask;
2605
for (unsigned i = 0; i != NumSrcElts; ++i)
2606
ExtMask.push_back(i);
2607
ExtMask.resize(NumDstElts, -1);
2608
llvm::Value *ExtSrcVal = Builder.CreateShuffleVector(SrcVal, ExtMask);
2609
// build identity
2610
SmallVector<int, 4> Mask;
2611
for (unsigned i = 0; i != NumDstElts; ++i)
2612
Mask.push_back(i);
2613
2614
// When the vector size is odd and .odd or .hi is used, the last element
2615
// of the Elts constant array will be one past the size of the vector.
2616
// Ignore the last element here, if it is greater than the mask size.
2617
if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size())
2618
NumSrcElts--;
2619
2620
// modify when what gets shuffled in
2621
for (unsigned i = 0; i != NumSrcElts; ++i)
2622
Mask[getAccessedFieldNo(i, Elts)] = i + NumDstElts;
2623
Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, Mask);
2624
} else {
2625
// We should never shorten the vector
2626
llvm_unreachable("unexpected shorten vector length");
2627
}
2628
} else {
2629
// If the Src is a scalar (not a vector), and the target is a vector it must
2630
// be updating one element.
2631
unsigned InIdx = getAccessedFieldNo(0, Elts);
2632
llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
2633
Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt);
2634
}
2635
2636
Builder.CreateStore(Vec, Dst.getExtVectorAddress(),
2637
Dst.isVolatileQualified());
2638
}
2639
2640
/// Store of global named registers are always calls to intrinsics.
2641
void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) {
2642
assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) &&
2643
"Bad type for register variable");
2644
llvm::MDNode *RegName = cast<llvm::MDNode>(
2645
cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata());
2646
assert(RegName && "Register LValue is not metadata");
2647
2648
// We accept integer and pointer types only
2649
llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType());
2650
llvm::Type *Ty = OrigTy;
2651
if (OrigTy->isPointerTy())
2652
Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
2653
llvm::Type *Types[] = { Ty };
2654
2655
llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types);
2656
llvm::Value *Value = Src.getScalarVal();
2657
if (OrigTy->isPointerTy())
2658
Value = Builder.CreatePtrToInt(Value, Ty);
2659
Builder.CreateCall(
2660
F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value});
2661
}
2662
2663
// setObjCGCLValueClass - sets class of the lvalue for the purpose of
2664
// generating write-barries API. It is currently a global, ivar,
2665
// or neither.
2666
static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
2667
LValue &LV,
2668
bool IsMemberAccess=false) {
2669
if (Ctx.getLangOpts().getGC() == LangOptions::NonGC)
2670
return;
2671
2672
if (isa<ObjCIvarRefExpr>(E)) {
2673
QualType ExpTy = E->getType();
2674
if (IsMemberAccess && ExpTy->isPointerType()) {
2675
// If ivar is a structure pointer, assigning to field of
2676
// this struct follows gcc's behavior and makes it a non-ivar
2677
// writer-barrier conservatively.
2678
ExpTy = ExpTy->castAs<PointerType>()->getPointeeType();
2679
if (ExpTy->isRecordType()) {
2680
LV.setObjCIvar(false);
2681
return;
2682
}
2683
}
2684
LV.setObjCIvar(true);
2685
auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E));
2686
LV.setBaseIvarExp(Exp->getBase());
2687
LV.setObjCArray(E->getType()->isArrayType());
2688
return;
2689
}
2690
2691
if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) {
2692
if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
2693
if (VD->hasGlobalStorage()) {
2694
LV.setGlobalObjCRef(true);
2695
LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None);
2696
}
2697
}
2698
LV.setObjCArray(E->getType()->isArrayType());
2699
return;
2700
}
2701
2702
if (const auto *Exp = dyn_cast<UnaryOperator>(E)) {
2703
setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2704
return;
2705
}
2706
2707
if (const auto *Exp = dyn_cast<ParenExpr>(E)) {
2708
setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2709
if (LV.isObjCIvar()) {
2710
// If cast is to a structure pointer, follow gcc's behavior and make it
2711
// a non-ivar write-barrier.
2712
QualType ExpTy = E->getType();
2713
if (ExpTy->isPointerType())
2714
ExpTy = ExpTy->castAs<PointerType>()->getPointeeType();
2715
if (ExpTy->isRecordType())
2716
LV.setObjCIvar(false);
2717
}
2718
return;
2719
}
2720
2721
if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) {
2722
setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV);
2723
return;
2724
}
2725
2726
if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) {
2727
setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2728
return;
2729
}
2730
2731
if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) {
2732
setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2733
return;
2734
}
2735
2736
if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) {
2737
setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2738
return;
2739
}
2740
2741
if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
2742
setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
2743
if (LV.isObjCIvar() && !LV.isObjCArray())
2744
// Using array syntax to assigning to what an ivar points to is not
2745
// same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
2746
LV.setObjCIvar(false);
2747
else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
2748
// Using array syntax to assigning to what global points to is not
2749
// same as assigning to the global itself. {id *G;} G[i] = 0;
2750
LV.setGlobalObjCRef(false);
2751
return;
2752
}
2753
2754
if (const auto *Exp = dyn_cast<MemberExpr>(E)) {
2755
setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true);
2756
// We don't know if member is an 'ivar', but this flag is looked at
2757
// only in the context of LV.isObjCIvar().
2758
LV.setObjCArray(E->getType()->isArrayType());
2759
return;
2760
}
2761
}
2762
2763
static LValue EmitThreadPrivateVarDeclLValue(
2764
CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr,
2765
llvm::Type *RealVarTy, SourceLocation Loc) {
2766
if (CGF.CGM.getLangOpts().OpenMPIRBuilder)
2767
Addr = CodeGenFunction::OMPBuilderCBHelpers::getAddrOfThreadPrivate(
2768
CGF, VD, Addr, Loc);
2769
else
2770
Addr =
2771
CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc);
2772
2773
Addr = Addr.withElementType(RealVarTy);
2774
return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2775
}
2776
2777
static Address emitDeclTargetVarDeclLValue(CodeGenFunction &CGF,
2778
const VarDecl *VD, QualType T) {
2779
std::optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res =
2780
OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD);
2781
// Return an invalid address if variable is MT_To (or MT_Enter starting with
2782
// OpenMP 5.2) and unified memory is not enabled. For all other cases: MT_Link
2783
// and MT_To (or MT_Enter) with unified memory, return a valid address.
2784
if (!Res || ((*Res == OMPDeclareTargetDeclAttr::MT_To ||
2785
*Res == OMPDeclareTargetDeclAttr::MT_Enter) &&
2786
!CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory()))
2787
return Address::invalid();
2788
assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) ||
2789
((*Res == OMPDeclareTargetDeclAttr::MT_To ||
2790
*Res == OMPDeclareTargetDeclAttr::MT_Enter) &&
2791
CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory())) &&
2792
"Expected link clause OR to clause with unified memory enabled.");
2793
QualType PtrTy = CGF.getContext().getPointerType(VD->getType());
2794
Address Addr = CGF.CGM.getOpenMPRuntime().getAddrOfDeclareTargetVar(VD);
2795
return CGF.EmitLoadOfPointer(Addr, PtrTy->castAs<PointerType>());
2796
}
2797
2798
Address
2799
CodeGenFunction::EmitLoadOfReference(LValue RefLVal,
2800
LValueBaseInfo *PointeeBaseInfo,
2801
TBAAAccessInfo *PointeeTBAAInfo) {
2802
llvm::LoadInst *Load =
2803
Builder.CreateLoad(RefLVal.getAddress(), RefLVal.isVolatile());
2804
CGM.DecorateInstructionWithTBAA(Load, RefLVal.getTBAAInfo());
2805
return makeNaturalAddressForPointer(Load, RefLVal.getType()->getPointeeType(),
2806
CharUnits(), /*ForPointeeType=*/true,
2807
PointeeBaseInfo, PointeeTBAAInfo);
2808
}
2809
2810
LValue CodeGenFunction::EmitLoadOfReferenceLValue(LValue RefLVal) {
2811
LValueBaseInfo PointeeBaseInfo;
2812
TBAAAccessInfo PointeeTBAAInfo;
2813
Address PointeeAddr = EmitLoadOfReference(RefLVal, &PointeeBaseInfo,
2814
&PointeeTBAAInfo);
2815
return MakeAddrLValue(PointeeAddr, RefLVal.getType()->getPointeeType(),
2816
PointeeBaseInfo, PointeeTBAAInfo);
2817
}
2818
2819
Address CodeGenFunction::EmitLoadOfPointer(Address Ptr,
2820
const PointerType *PtrTy,
2821
LValueBaseInfo *BaseInfo,
2822
TBAAAccessInfo *TBAAInfo) {
2823
llvm::Value *Addr = Builder.CreateLoad(Ptr);
2824
return makeNaturalAddressForPointer(Addr, PtrTy->getPointeeType(),
2825
CharUnits(), /*ForPointeeType=*/true,
2826
BaseInfo, TBAAInfo);
2827
}
2828
2829
LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr,
2830
const PointerType *PtrTy) {
2831
LValueBaseInfo BaseInfo;
2832
TBAAAccessInfo TBAAInfo;
2833
Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &BaseInfo, &TBAAInfo);
2834
return MakeAddrLValue(Addr, PtrTy->getPointeeType(), BaseInfo, TBAAInfo);
2835
}
2836
2837
static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
2838
const Expr *E, const VarDecl *VD) {
2839
QualType T = E->getType();
2840
2841
// If it's thread_local, emit a call to its wrapper function instead.
2842
if (VD->getTLSKind() == VarDecl::TLS_Dynamic &&
2843
CGF.CGM.getCXXABI().usesThreadWrapperFunction(VD))
2844
return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T);
2845
// Check if the variable is marked as declare target with link clause in
2846
// device codegen.
2847
if (CGF.getLangOpts().OpenMPIsTargetDevice) {
2848
Address Addr = emitDeclTargetVarDeclLValue(CGF, VD, T);
2849
if (Addr.isValid())
2850
return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2851
}
2852
2853
llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
2854
2855
if (VD->getTLSKind() != VarDecl::TLS_None)
2856
V = CGF.Builder.CreateThreadLocalAddress(V);
2857
2858
llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType());
2859
CharUnits Alignment = CGF.getContext().getDeclAlign(VD);
2860
Address Addr(V, RealVarTy, Alignment);
2861
// Emit reference to the private copy of the variable if it is an OpenMP
2862
// threadprivate variable.
2863
if (CGF.getLangOpts().OpenMP && !CGF.getLangOpts().OpenMPSimd &&
2864
VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2865
return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy,
2866
E->getExprLoc());
2867
}
2868
LValue LV = VD->getType()->isReferenceType() ?
2869
CGF.EmitLoadOfReferenceLValue(Addr, VD->getType(),
2870
AlignmentSource::Decl) :
2871
CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2872
setObjCGCLValueClass(CGF.getContext(), E, LV);
2873
return LV;
2874
}
2875
2876
llvm::Constant *CodeGenModule::getRawFunctionPointer(GlobalDecl GD,
2877
llvm::Type *Ty) {
2878
const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
2879
if (FD->hasAttr<WeakRefAttr>()) {
2880
ConstantAddress aliasee = GetWeakRefReference(FD);
2881
return aliasee.getPointer();
2882
}
2883
2884
llvm::Constant *V = GetAddrOfFunction(GD, Ty);
2885
return V;
2886
}
2887
2888
static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF, const Expr *E,
2889
GlobalDecl GD) {
2890
const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
2891
llvm::Constant *V = CGF.CGM.getFunctionPointer(GD);
2892
CharUnits Alignment = CGF.getContext().getDeclAlign(FD);
2893
return CGF.MakeAddrLValue(V, E->getType(), Alignment,
2894
AlignmentSource::Decl);
2895
}
2896
2897
static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD,
2898
llvm::Value *ThisValue) {
2899
2900
return CGF.EmitLValueForLambdaField(FD, ThisValue);
2901
}
2902
2903
/// Named Registers are named metadata pointing to the register name
2904
/// which will be read from/written to as an argument to the intrinsic
2905
/// @llvm.read/write_register.
2906
/// So far, only the name is being passed down, but other options such as
2907
/// register type, allocation type or even optimization options could be
2908
/// passed down via the metadata node.
2909
static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) {
2910
SmallString<64> Name("llvm.named.register.");
2911
AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>();
2912
assert(Asm->getLabel().size() < 64-Name.size() &&
2913
"Register name too big");
2914
Name.append(Asm->getLabel());
2915
llvm::NamedMDNode *M =
2916
CGM.getModule().getOrInsertNamedMetadata(Name);
2917
if (M->getNumOperands() == 0) {
2918
llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(),
2919
Asm->getLabel());
2920
llvm::Metadata *Ops[] = {Str};
2921
M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
2922
}
2923
2924
CharUnits Alignment = CGM.getContext().getDeclAlign(VD);
2925
2926
llvm::Value *Ptr =
2927
llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0));
2928
return LValue::MakeGlobalReg(Ptr, Alignment, VD->getType());
2929
}
2930
2931
/// Determine whether we can emit a reference to \p VD from the current
2932
/// context, despite not necessarily having seen an odr-use of the variable in
2933
/// this context.
2934
static bool canEmitSpuriousReferenceToVariable(CodeGenFunction &CGF,
2935
const DeclRefExpr *E,
2936
const VarDecl *VD) {
2937
// For a variable declared in an enclosing scope, do not emit a spurious
2938
// reference even if we have a capture, as that will emit an unwarranted
2939
// reference to our capture state, and will likely generate worse code than
2940
// emitting a local copy.
2941
if (E->refersToEnclosingVariableOrCapture())
2942
return false;
2943
2944
// For a local declaration declared in this function, we can always reference
2945
// it even if we don't have an odr-use.
2946
if (VD->hasLocalStorage()) {
2947
return VD->getDeclContext() ==
2948
dyn_cast_or_null<DeclContext>(CGF.CurCodeDecl);
2949
}
2950
2951
// For a global declaration, we can emit a reference to it if we know
2952
// for sure that we are able to emit a definition of it.
2953
VD = VD->getDefinition(CGF.getContext());
2954
if (!VD)
2955
return false;
2956
2957
// Don't emit a spurious reference if it might be to a variable that only
2958
// exists on a different device / target.
2959
// FIXME: This is unnecessarily broad. Check whether this would actually be a
2960
// cross-target reference.
2961
if (CGF.getLangOpts().OpenMP || CGF.getLangOpts().CUDA ||
2962
CGF.getLangOpts().OpenCL) {
2963
return false;
2964
}
2965
2966
// We can emit a spurious reference only if the linkage implies that we'll
2967
// be emitting a non-interposable symbol that will be retained until link
2968
// time.
2969
switch (CGF.CGM.getLLVMLinkageVarDefinition(VD)) {
2970
case llvm::GlobalValue::ExternalLinkage:
2971
case llvm::GlobalValue::LinkOnceODRLinkage:
2972
case llvm::GlobalValue::WeakODRLinkage:
2973
case llvm::GlobalValue::InternalLinkage:
2974
case llvm::GlobalValue::PrivateLinkage:
2975
return true;
2976
default:
2977
return false;
2978
}
2979
}
2980
2981
LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
2982
const NamedDecl *ND = E->getDecl();
2983
QualType T = E->getType();
2984
2985
assert(E->isNonOdrUse() != NOUR_Unevaluated &&
2986
"should not emit an unevaluated operand");
2987
2988
if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2989
// Global Named registers access via intrinsics only
2990
if (VD->getStorageClass() == SC_Register &&
2991
VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl())
2992
return EmitGlobalNamedRegister(VD, CGM);
2993
2994
// If this DeclRefExpr does not constitute an odr-use of the variable,
2995
// we're not permitted to emit a reference to it in general, and it might
2996
// not be captured if capture would be necessary for a use. Emit the
2997
// constant value directly instead.
2998
if (E->isNonOdrUse() == NOUR_Constant &&
2999
(VD->getType()->isReferenceType() ||
3000
!canEmitSpuriousReferenceToVariable(*this, E, VD))) {
3001
VD->getAnyInitializer(VD);
3002
llvm::Constant *Val = ConstantEmitter(*this).emitAbstract(
3003
E->getLocation(), *VD->evaluateValue(), VD->getType());
3004
assert(Val && "failed to emit constant expression");
3005
3006
Address Addr = Address::invalid();
3007
if (!VD->getType()->isReferenceType()) {
3008
// Spill the constant value to a global.
3009
Addr = CGM.createUnnamedGlobalFrom(*VD, Val,
3010
getContext().getDeclAlign(VD));
3011
llvm::Type *VarTy = getTypes().ConvertTypeForMem(VD->getType());
3012
auto *PTy = llvm::PointerType::get(
3013
VarTy, getTypes().getTargetAddressSpace(VD->getType()));
3014
Addr = Builder.CreatePointerBitCastOrAddrSpaceCast(Addr, PTy, VarTy);
3015
} else {
3016
// Should we be using the alignment of the constant pointer we emitted?
3017
CharUnits Alignment =
3018
CGM.getNaturalTypeAlignment(E->getType(),
3019
/* BaseInfo= */ nullptr,
3020
/* TBAAInfo= */ nullptr,
3021
/* forPointeeType= */ true);
3022
Addr = makeNaturalAddressForPointer(Val, T, Alignment);
3023
}
3024
return MakeAddrLValue(Addr, T, AlignmentSource::Decl);
3025
}
3026
3027
// FIXME: Handle other kinds of non-odr-use DeclRefExprs.
3028
3029
// Check for captured variables.
3030
if (E->refersToEnclosingVariableOrCapture()) {
3031
VD = VD->getCanonicalDecl();
3032
if (auto *FD = LambdaCaptureFields.lookup(VD))
3033
return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
3034
if (CapturedStmtInfo) {
3035
auto I = LocalDeclMap.find(VD);
3036
if (I != LocalDeclMap.end()) {
3037
LValue CapLVal;
3038
if (VD->getType()->isReferenceType())
3039
CapLVal = EmitLoadOfReferenceLValue(I->second, VD->getType(),
3040
AlignmentSource::Decl);
3041
else
3042
CapLVal = MakeAddrLValue(I->second, T);
3043
// Mark lvalue as nontemporal if the variable is marked as nontemporal
3044
// in simd context.
3045
if (getLangOpts().OpenMP &&
3046
CGM.getOpenMPRuntime().isNontemporalDecl(VD))
3047
CapLVal.setNontemporal(/*Value=*/true);
3048
return CapLVal;
3049
}
3050
LValue CapLVal =
3051
EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD),
3052
CapturedStmtInfo->getContextValue());
3053
Address LValueAddress = CapLVal.getAddress();
3054
CapLVal = MakeAddrLValue(Address(LValueAddress.emitRawPointer(*this),
3055
LValueAddress.getElementType(),
3056
getContext().getDeclAlign(VD)),
3057
CapLVal.getType(),
3058
LValueBaseInfo(AlignmentSource::Decl),
3059
CapLVal.getTBAAInfo());
3060
// Mark lvalue as nontemporal if the variable is marked as nontemporal
3061
// in simd context.
3062
if (getLangOpts().OpenMP &&
3063
CGM.getOpenMPRuntime().isNontemporalDecl(VD))
3064
CapLVal.setNontemporal(/*Value=*/true);
3065
return CapLVal;
3066
}
3067
3068
assert(isa<BlockDecl>(CurCodeDecl));
3069
Address addr = GetAddrOfBlockDecl(VD);
3070
return MakeAddrLValue(addr, T, AlignmentSource::Decl);
3071
}
3072
}
3073
3074
// FIXME: We should be able to assert this for FunctionDecls as well!
3075
// FIXME: We should be able to assert this for all DeclRefExprs, not just
3076
// those with a valid source location.
3077
assert((ND->isUsed(false) || !isa<VarDecl>(ND) || E->isNonOdrUse() ||
3078
!E->getLocation().isValid()) &&
3079
"Should not use decl without marking it used!");
3080
3081
if (ND->hasAttr<WeakRefAttr>()) {
3082
const auto *VD = cast<ValueDecl>(ND);
3083
ConstantAddress Aliasee = CGM.GetWeakRefReference(VD);
3084
return MakeAddrLValue(Aliasee, T, AlignmentSource::Decl);
3085
}
3086
3087
if (const auto *VD = dyn_cast<VarDecl>(ND)) {
3088
// Check if this is a global variable.
3089
if (VD->hasLinkage() || VD->isStaticDataMember())
3090
return EmitGlobalVarDeclLValue(*this, E, VD);
3091
3092
Address addr = Address::invalid();
3093
3094
// The variable should generally be present in the local decl map.
3095
auto iter = LocalDeclMap.find(VD);
3096
if (iter != LocalDeclMap.end()) {
3097
addr = iter->second;
3098
3099
// Otherwise, it might be static local we haven't emitted yet for
3100
// some reason; most likely, because it's in an outer function.
3101
} else if (VD->isStaticLocal()) {
3102
llvm::Constant *var = CGM.getOrCreateStaticVarDecl(
3103
*VD, CGM.getLLVMLinkageVarDefinition(VD));
3104
addr = Address(
3105
var, ConvertTypeForMem(VD->getType()), getContext().getDeclAlign(VD));
3106
3107
// No other cases for now.
3108
} else {
3109
llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?");
3110
}
3111
3112
// Handle threadlocal function locals.
3113
if (VD->getTLSKind() != VarDecl::TLS_None)
3114
addr = addr.withPointer(
3115
Builder.CreateThreadLocalAddress(addr.getBasePointer()),
3116
NotKnownNonNull);
3117
3118
// Check for OpenMP threadprivate variables.
3119
if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd &&
3120
VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
3121
return EmitThreadPrivateVarDeclLValue(
3122
*this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()),
3123
E->getExprLoc());
3124
}
3125
3126
// Drill into block byref variables.
3127
bool isBlockByref = VD->isEscapingByref();
3128
if (isBlockByref) {
3129
addr = emitBlockByrefAddress(addr, VD);
3130
}
3131
3132
// Drill into reference types.
3133
LValue LV = VD->getType()->isReferenceType() ?
3134
EmitLoadOfReferenceLValue(addr, VD->getType(), AlignmentSource::Decl) :
3135
MakeAddrLValue(addr, T, AlignmentSource::Decl);
3136
3137
bool isLocalStorage = VD->hasLocalStorage();
3138
3139
bool NonGCable = isLocalStorage &&
3140
!VD->getType()->isReferenceType() &&
3141
!isBlockByref;
3142
if (NonGCable) {
3143
LV.getQuals().removeObjCGCAttr();
3144
LV.setNonGC(true);
3145
}
3146
3147
bool isImpreciseLifetime =
3148
(isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>());
3149
if (isImpreciseLifetime)
3150
LV.setARCPreciseLifetime(ARCImpreciseLifetime);
3151
setObjCGCLValueClass(getContext(), E, LV);
3152
return LV;
3153
}
3154
3155
if (const auto *FD = dyn_cast<FunctionDecl>(ND))
3156
return EmitFunctionDeclLValue(*this, E, FD);
3157
3158
// FIXME: While we're emitting a binding from an enclosing scope, all other
3159
// DeclRefExprs we see should be implicitly treated as if they also refer to
3160
// an enclosing scope.
3161
if (const auto *BD = dyn_cast<BindingDecl>(ND)) {
3162
if (E->refersToEnclosingVariableOrCapture()) {
3163
auto *FD = LambdaCaptureFields.lookup(BD);
3164
return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
3165
}
3166
return EmitLValue(BD->getBinding());
3167
}
3168
3169
// We can form DeclRefExprs naming GUID declarations when reconstituting
3170
// non-type template parameters into expressions.
3171
if (const auto *GD = dyn_cast<MSGuidDecl>(ND))
3172
return MakeAddrLValue(CGM.GetAddrOfMSGuidDecl(GD), T,
3173
AlignmentSource::Decl);
3174
3175
if (const auto *TPO = dyn_cast<TemplateParamObjectDecl>(ND)) {
3176
auto ATPO = CGM.GetAddrOfTemplateParamObject(TPO);
3177
auto AS = getLangASFromTargetAS(ATPO.getAddressSpace());
3178
3179
if (AS != T.getAddressSpace()) {
3180
auto TargetAS = getContext().getTargetAddressSpace(T.getAddressSpace());
3181
auto PtrTy = ATPO.getElementType()->getPointerTo(TargetAS);
3182
auto ASC = getTargetHooks().performAddrSpaceCast(
3183
CGM, ATPO.getPointer(), AS, T.getAddressSpace(), PtrTy);
3184
ATPO = ConstantAddress(ASC, ATPO.getElementType(), ATPO.getAlignment());
3185
}
3186
3187
return MakeAddrLValue(ATPO, T, AlignmentSource::Decl);
3188
}
3189
3190
llvm_unreachable("Unhandled DeclRefExpr");
3191
}
3192
3193
LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
3194
// __extension__ doesn't affect lvalue-ness.
3195
if (E->getOpcode() == UO_Extension)
3196
return EmitLValue(E->getSubExpr());
3197
3198
QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
3199
switch (E->getOpcode()) {
3200
default: llvm_unreachable("Unknown unary operator lvalue!");
3201
case UO_Deref: {
3202
QualType T = E->getSubExpr()->getType()->getPointeeType();
3203
assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
3204
3205
LValueBaseInfo BaseInfo;
3206
TBAAAccessInfo TBAAInfo;
3207
Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &BaseInfo,
3208
&TBAAInfo);
3209
LValue LV = MakeAddrLValue(Addr, T, BaseInfo, TBAAInfo);
3210
LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
3211
3212
// We should not generate __weak write barrier on indirect reference
3213
// of a pointer to object; as in void foo (__weak id *param); *param = 0;
3214
// But, we continue to generate __strong write barrier on indirect write
3215
// into a pointer to object.
3216
if (getLangOpts().ObjC &&
3217
getLangOpts().getGC() != LangOptions::NonGC &&
3218
LV.isObjCWeak())
3219
LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
3220
return LV;
3221
}
3222
case UO_Real:
3223
case UO_Imag: {
3224
LValue LV = EmitLValue(E->getSubExpr());
3225
assert(LV.isSimple() && "real/imag on non-ordinary l-value");
3226
3227
// __real is valid on scalars. This is a faster way of testing that.
3228
// __imag can only produce an rvalue on scalars.
3229
if (E->getOpcode() == UO_Real &&
3230
!LV.getAddress().getElementType()->isStructTy()) {
3231
assert(E->getSubExpr()->getType()->isArithmeticType());
3232
return LV;
3233
}
3234
3235
QualType T = ExprTy->castAs<ComplexType>()->getElementType();
3236
3237
Address Component =
3238
(E->getOpcode() == UO_Real
3239
? emitAddrOfRealComponent(LV.getAddress(), LV.getType())
3240
: emitAddrOfImagComponent(LV.getAddress(), LV.getType()));
3241
LValue ElemLV = MakeAddrLValue(Component, T, LV.getBaseInfo(),
3242
CGM.getTBAAInfoForSubobject(LV, T));
3243
ElemLV.getQuals().addQualifiers(LV.getQuals());
3244
return ElemLV;
3245
}
3246
case UO_PreInc:
3247
case UO_PreDec: {
3248
LValue LV = EmitLValue(E->getSubExpr());
3249
bool isInc = E->getOpcode() == UO_PreInc;
3250
3251
if (E->getType()->isAnyComplexType())
3252
EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
3253
else
3254
EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
3255
return LV;
3256
}
3257
}
3258
}
3259
3260
LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
3261
return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
3262
E->getType(), AlignmentSource::Decl);
3263
}
3264
3265
LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
3266
return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
3267
E->getType(), AlignmentSource::Decl);
3268
}
3269
3270
LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
3271
auto SL = E->getFunctionName();
3272
assert(SL != nullptr && "No StringLiteral name in PredefinedExpr");
3273
StringRef FnName = CurFn->getName();
3274
if (FnName.starts_with("\01"))
3275
FnName = FnName.substr(1);
3276
StringRef NameItems[] = {
3277
PredefinedExpr::getIdentKindName(E->getIdentKind()), FnName};
3278
std::string GVName = llvm::join(NameItems, NameItems + 2, ".");
3279
if (auto *BD = dyn_cast_or_null<BlockDecl>(CurCodeDecl)) {
3280
std::string Name = std::string(SL->getString());
3281
if (!Name.empty()) {
3282
unsigned Discriminator =
3283
CGM.getCXXABI().getMangleContext().getBlockId(BD, true);
3284
if (Discriminator)
3285
Name += "_" + Twine(Discriminator + 1).str();
3286
auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str());
3287
return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
3288
} else {
3289
auto C =
3290
CGM.GetAddrOfConstantCString(std::string(FnName), GVName.c_str());
3291
return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
3292
}
3293
}
3294
auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName);
3295
return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
3296
}
3297
3298
/// Emit a type description suitable for use by a runtime sanitizer library. The
3299
/// format of a type descriptor is
3300
///
3301
/// \code
3302
/// { i16 TypeKind, i16 TypeInfo }
3303
/// \endcode
3304
///
3305
/// followed by an array of i8 containing the type name. TypeKind is 0 for an
3306
/// integer, 1 for a floating point value, and -1 for anything else.
3307
llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) {
3308
// Only emit each type's descriptor once.
3309
if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T))
3310
return C;
3311
3312
uint16_t TypeKind = -1;
3313
uint16_t TypeInfo = 0;
3314
3315
if (T->isIntegerType()) {
3316
TypeKind = 0;
3317
TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) |
3318
(T->isSignedIntegerType() ? 1 : 0);
3319
} else if (T->isFloatingType()) {
3320
TypeKind = 1;
3321
TypeInfo = getContext().getTypeSize(T);
3322
}
3323
3324
// Format the type name as if for a diagnostic, including quotes and
3325
// optionally an 'aka'.
3326
SmallString<32> Buffer;
3327
CGM.getDiags().ConvertArgToString(
3328
DiagnosticsEngine::ak_qualtype, (intptr_t)T.getAsOpaquePtr(), StringRef(),
3329
StringRef(), std::nullopt, Buffer, std::nullopt);
3330
3331
llvm::Constant *Components[] = {
3332
Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo),
3333
llvm::ConstantDataArray::getString(getLLVMContext(), Buffer)
3334
};
3335
llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components);
3336
3337
auto *GV = new llvm::GlobalVariable(
3338
CGM.getModule(), Descriptor->getType(),
3339
/*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor);
3340
GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3341
CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV);
3342
3343
// Remember the descriptor for this type.
3344
CGM.setTypeDescriptorInMap(T, GV);
3345
3346
return GV;
3347
}
3348
3349
llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) {
3350
llvm::Type *TargetTy = IntPtrTy;
3351
3352
if (V->getType() == TargetTy)
3353
return V;
3354
3355
// Floating-point types which fit into intptr_t are bitcast to integers
3356
// and then passed directly (after zero-extension, if necessary).
3357
if (V->getType()->isFloatingPointTy()) {
3358
unsigned Bits = V->getType()->getPrimitiveSizeInBits().getFixedValue();
3359
if (Bits <= TargetTy->getIntegerBitWidth())
3360
V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(),
3361
Bits));
3362
}
3363
3364
// Integers which fit in intptr_t are zero-extended and passed directly.
3365
if (V->getType()->isIntegerTy() &&
3366
V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth())
3367
return Builder.CreateZExt(V, TargetTy);
3368
3369
// Pointers are passed directly, everything else is passed by address.
3370
if (!V->getType()->isPointerTy()) {
3371
RawAddress Ptr = CreateDefaultAlignTempAlloca(V->getType());
3372
Builder.CreateStore(V, Ptr);
3373
V = Ptr.getPointer();
3374
}
3375
return Builder.CreatePtrToInt(V, TargetTy);
3376
}
3377
3378
/// Emit a representation of a SourceLocation for passing to a handler
3379
/// in a sanitizer runtime library. The format for this data is:
3380
/// \code
3381
/// struct SourceLocation {
3382
/// const char *Filename;
3383
/// int32_t Line, Column;
3384
/// };
3385
/// \endcode
3386
/// For an invalid SourceLocation, the Filename pointer is null.
3387
llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
3388
llvm::Constant *Filename;
3389
int Line, Column;
3390
3391
PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
3392
if (PLoc.isValid()) {
3393
StringRef FilenameString = PLoc.getFilename();
3394
3395
int PathComponentsToStrip =
3396
CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip;
3397
if (PathComponentsToStrip < 0) {
3398
assert(PathComponentsToStrip != INT_MIN);
3399
int PathComponentsToKeep = -PathComponentsToStrip;
3400
auto I = llvm::sys::path::rbegin(FilenameString);
3401
auto E = llvm::sys::path::rend(FilenameString);
3402
while (I != E && --PathComponentsToKeep)
3403
++I;
3404
3405
FilenameString = FilenameString.substr(I - E);
3406
} else if (PathComponentsToStrip > 0) {
3407
auto I = llvm::sys::path::begin(FilenameString);
3408
auto E = llvm::sys::path::end(FilenameString);
3409
while (I != E && PathComponentsToStrip--)
3410
++I;
3411
3412
if (I != E)
3413
FilenameString =
3414
FilenameString.substr(I - llvm::sys::path::begin(FilenameString));
3415
else
3416
FilenameString = llvm::sys::path::filename(FilenameString);
3417
}
3418
3419
auto FilenameGV =
3420
CGM.GetAddrOfConstantCString(std::string(FilenameString), ".src");
3421
CGM.getSanitizerMetadata()->disableSanitizerForGlobal(
3422
cast<llvm::GlobalVariable>(
3423
FilenameGV.getPointer()->stripPointerCasts()));
3424
Filename = FilenameGV.getPointer();
3425
Line = PLoc.getLine();
3426
Column = PLoc.getColumn();
3427
} else {
3428
Filename = llvm::Constant::getNullValue(Int8PtrTy);
3429
Line = Column = 0;
3430
}
3431
3432
llvm::Constant *Data[] = {Filename, Builder.getInt32(Line),
3433
Builder.getInt32(Column)};
3434
3435
return llvm::ConstantStruct::getAnon(Data);
3436
}
3437
3438
namespace {
3439
/// Specify under what conditions this check can be recovered
3440
enum class CheckRecoverableKind {
3441
/// Always terminate program execution if this check fails.
3442
Unrecoverable,
3443
/// Check supports recovering, runtime has both fatal (noreturn) and
3444
/// non-fatal handlers for this check.
3445
Recoverable,
3446
/// Runtime conditionally aborts, always need to support recovery.
3447
AlwaysRecoverable
3448
};
3449
}
3450
3451
static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) {
3452
assert(Kind.countPopulation() == 1);
3453
if (Kind == SanitizerKind::Vptr)
3454
return CheckRecoverableKind::AlwaysRecoverable;
3455
else if (Kind == SanitizerKind::Return || Kind == SanitizerKind::Unreachable)
3456
return CheckRecoverableKind::Unrecoverable;
3457
else
3458
return CheckRecoverableKind::Recoverable;
3459
}
3460
3461
namespace {
3462
struct SanitizerHandlerInfo {
3463
char const *const Name;
3464
unsigned Version;
3465
};
3466
}
3467
3468
const SanitizerHandlerInfo SanitizerHandlers[] = {
3469
#define SANITIZER_CHECK(Enum, Name, Version) {#Name, Version},
3470
LIST_SANITIZER_CHECKS
3471
#undef SANITIZER_CHECK
3472
};
3473
3474
static void emitCheckHandlerCall(CodeGenFunction &CGF,
3475
llvm::FunctionType *FnType,
3476
ArrayRef<llvm::Value *> FnArgs,
3477
SanitizerHandler CheckHandler,
3478
CheckRecoverableKind RecoverKind, bool IsFatal,
3479
llvm::BasicBlock *ContBB) {
3480
assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable);
3481
std::optional<ApplyDebugLocation> DL;
3482
if (!CGF.Builder.getCurrentDebugLocation()) {
3483
// Ensure that the call has at least an artificial debug location.
3484
DL.emplace(CGF, SourceLocation());
3485
}
3486
bool NeedsAbortSuffix =
3487
IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable;
3488
bool MinimalRuntime = CGF.CGM.getCodeGenOpts().SanitizeMinimalRuntime;
3489
const SanitizerHandlerInfo &CheckInfo = SanitizerHandlers[CheckHandler];
3490
const StringRef CheckName = CheckInfo.Name;
3491
std::string FnName = "__ubsan_handle_" + CheckName.str();
3492
if (CheckInfo.Version && !MinimalRuntime)
3493
FnName += "_v" + llvm::utostr(CheckInfo.Version);
3494
if (MinimalRuntime)
3495
FnName += "_minimal";
3496
if (NeedsAbortSuffix)
3497
FnName += "_abort";
3498
bool MayReturn =
3499
!IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable;
3500
3501
llvm::AttrBuilder B(CGF.getLLVMContext());
3502
if (!MayReturn) {
3503
B.addAttribute(llvm::Attribute::NoReturn)
3504
.addAttribute(llvm::Attribute::NoUnwind);
3505
}
3506
B.addUWTableAttr(llvm::UWTableKind::Default);
3507
3508
llvm::FunctionCallee Fn = CGF.CGM.CreateRuntimeFunction(
3509
FnType, FnName,
3510
llvm::AttributeList::get(CGF.getLLVMContext(),
3511
llvm::AttributeList::FunctionIndex, B),
3512
/*Local=*/true);
3513
llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs);
3514
if (!MayReturn) {
3515
HandlerCall->setDoesNotReturn();
3516
CGF.Builder.CreateUnreachable();
3517
} else {
3518
CGF.Builder.CreateBr(ContBB);
3519
}
3520
}
3521
3522
void CodeGenFunction::EmitCheck(
3523
ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
3524
SanitizerHandler CheckHandler, ArrayRef<llvm::Constant *> StaticArgs,
3525
ArrayRef<llvm::Value *> DynamicArgs) {
3526
assert(IsSanitizerScope);
3527
assert(Checked.size() > 0);
3528
assert(CheckHandler >= 0 &&
3529
size_t(CheckHandler) < std::size(SanitizerHandlers));
3530
const StringRef CheckName = SanitizerHandlers[CheckHandler].Name;
3531
3532
llvm::Value *FatalCond = nullptr;
3533
llvm::Value *RecoverableCond = nullptr;
3534
llvm::Value *TrapCond = nullptr;
3535
for (int i = 0, n = Checked.size(); i < n; ++i) {
3536
llvm::Value *Check = Checked[i].first;
3537
// -fsanitize-trap= overrides -fsanitize-recover=.
3538
llvm::Value *&Cond =
3539
CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second)
3540
? TrapCond
3541
: CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second)
3542
? RecoverableCond
3543
: FatalCond;
3544
Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check;
3545
}
3546
3547
if (ClSanitizeGuardChecks) {
3548
llvm::Value *Allow =
3549
Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::allow_ubsan_check),
3550
llvm::ConstantInt::get(CGM.Int8Ty, CheckHandler));
3551
3552
for (llvm::Value **Cond : {&FatalCond, &RecoverableCond, &TrapCond}) {
3553
if (*Cond)
3554
*Cond = Builder.CreateOr(*Cond, Builder.CreateNot(Allow));
3555
}
3556
}
3557
3558
if (TrapCond)
3559
EmitTrapCheck(TrapCond, CheckHandler);
3560
if (!FatalCond && !RecoverableCond)
3561
return;
3562
3563
llvm::Value *JointCond;
3564
if (FatalCond && RecoverableCond)
3565
JointCond = Builder.CreateAnd(FatalCond, RecoverableCond);
3566
else
3567
JointCond = FatalCond ? FatalCond : RecoverableCond;
3568
assert(JointCond);
3569
3570
CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second);
3571
assert(SanOpts.has(Checked[0].second));
3572
#ifndef NDEBUG
3573
for (int i = 1, n = Checked.size(); i < n; ++i) {
3574
assert(RecoverKind == getRecoverableKind(Checked[i].second) &&
3575
"All recoverable kinds in a single check must be same!");
3576
assert(SanOpts.has(Checked[i].second));
3577
}
3578
#endif
3579
3580
llvm::BasicBlock *Cont = createBasicBlock("cont");
3581
llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName);
3582
llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers);
3583
// Give hint that we very much don't expect to execute the handler
3584
llvm::MDBuilder MDHelper(getLLVMContext());
3585
llvm::MDNode *Node = MDHelper.createLikelyBranchWeights();
3586
Branch->setMetadata(llvm::LLVMContext::MD_prof, Node);
3587
EmitBlock(Handlers);
3588
3589
// Handler functions take an i8* pointing to the (handler-specific) static
3590
// information block, followed by a sequence of intptr_t arguments
3591
// representing operand values.
3592
SmallVector<llvm::Value *, 4> Args;
3593
SmallVector<llvm::Type *, 4> ArgTypes;
3594
if (!CGM.getCodeGenOpts().SanitizeMinimalRuntime) {
3595
Args.reserve(DynamicArgs.size() + 1);
3596
ArgTypes.reserve(DynamicArgs.size() + 1);
3597
3598
// Emit handler arguments and create handler function type.
3599
if (!StaticArgs.empty()) {
3600
llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
3601
auto *InfoPtr = new llvm::GlobalVariable(
3602
CGM.getModule(), Info->getType(), false,
3603
llvm::GlobalVariable::PrivateLinkage, Info, "", nullptr,
3604
llvm::GlobalVariable::NotThreadLocal,
3605
CGM.getDataLayout().getDefaultGlobalsAddressSpace());
3606
InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3607
CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
3608
Args.push_back(InfoPtr);
3609
ArgTypes.push_back(Args.back()->getType());
3610
}
3611
3612
for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) {
3613
Args.push_back(EmitCheckValue(DynamicArgs[i]));
3614
ArgTypes.push_back(IntPtrTy);
3615
}
3616
}
3617
3618
llvm::FunctionType *FnType =
3619
llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false);
3620
3621
if (!FatalCond || !RecoverableCond) {
3622
// Simple case: we need to generate a single handler call, either
3623
// fatal, or non-fatal.
3624
emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind,
3625
(FatalCond != nullptr), Cont);
3626
} else {
3627
// Emit two handler calls: first one for set of unrecoverable checks,
3628
// another one for recoverable.
3629
llvm::BasicBlock *NonFatalHandlerBB =
3630
createBasicBlock("non_fatal." + CheckName);
3631
llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName);
3632
Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB);
3633
EmitBlock(FatalHandlerBB);
3634
emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, true,
3635
NonFatalHandlerBB);
3636
EmitBlock(NonFatalHandlerBB);
3637
emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, false,
3638
Cont);
3639
}
3640
3641
EmitBlock(Cont);
3642
}
3643
3644
void CodeGenFunction::EmitCfiSlowPathCheck(
3645
SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId,
3646
llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) {
3647
llvm::BasicBlock *Cont = createBasicBlock("cfi.cont");
3648
3649
llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath");
3650
llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB);
3651
3652
llvm::MDBuilder MDHelper(getLLVMContext());
3653
llvm::MDNode *Node = MDHelper.createLikelyBranchWeights();
3654
BI->setMetadata(llvm::LLVMContext::MD_prof, Node);
3655
3656
EmitBlock(CheckBB);
3657
3658
bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind);
3659
3660
llvm::CallInst *CheckCall;
3661
llvm::FunctionCallee SlowPathFn;
3662
if (WithDiag) {
3663
llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
3664
auto *InfoPtr =
3665
new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
3666
llvm::GlobalVariable::PrivateLinkage, Info);
3667
InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3668
CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
3669
3670
SlowPathFn = CGM.getModule().getOrInsertFunction(
3671
"__cfi_slowpath_diag",
3672
llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy},
3673
false));
3674
CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr, InfoPtr});
3675
} else {
3676
SlowPathFn = CGM.getModule().getOrInsertFunction(
3677
"__cfi_slowpath",
3678
llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false));
3679
CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr});
3680
}
3681
3682
CGM.setDSOLocal(
3683
cast<llvm::GlobalValue>(SlowPathFn.getCallee()->stripPointerCasts()));
3684
CheckCall->setDoesNotThrow();
3685
3686
EmitBlock(Cont);
3687
}
3688
3689
// Emit a stub for __cfi_check function so that the linker knows about this
3690
// symbol in LTO mode.
3691
void CodeGenFunction::EmitCfiCheckStub() {
3692
llvm::Module *M = &CGM.getModule();
3693
ASTContext &C = getContext();
3694
QualType QInt64Ty = C.getIntTypeForBitwidth(64, false);
3695
3696
FunctionArgList FnArgs;
3697
ImplicitParamDecl ArgCallsiteTypeId(C, QInt64Ty, ImplicitParamKind::Other);
3698
ImplicitParamDecl ArgAddr(C, C.VoidPtrTy, ImplicitParamKind::Other);
3699
ImplicitParamDecl ArgCFICheckFailData(C, C.VoidPtrTy,
3700
ImplicitParamKind::Other);
3701
FnArgs.push_back(&ArgCallsiteTypeId);
3702
FnArgs.push_back(&ArgAddr);
3703
FnArgs.push_back(&ArgCFICheckFailData);
3704
const CGFunctionInfo &FI =
3705
CGM.getTypes().arrangeBuiltinFunctionDeclaration(C.VoidTy, FnArgs);
3706
3707
llvm::Function *F = llvm::Function::Create(
3708
llvm::FunctionType::get(VoidTy, {Int64Ty, VoidPtrTy, VoidPtrTy}, false),
3709
llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M);
3710
CGM.SetLLVMFunctionAttributes(GlobalDecl(), FI, F, /*IsThunk=*/false);
3711
CGM.SetLLVMFunctionAttributesForDefinition(nullptr, F);
3712
F->setAlignment(llvm::Align(4096));
3713
CGM.setDSOLocal(F);
3714
3715
llvm::LLVMContext &Ctx = M->getContext();
3716
llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F);
3717
// CrossDSOCFI pass is not executed if there is no executable code.
3718
SmallVector<llvm::Value*> Args{F->getArg(2), F->getArg(1)};
3719
llvm::CallInst::Create(M->getFunction("__cfi_check_fail"), Args, "", BB);
3720
llvm::ReturnInst::Create(Ctx, nullptr, BB);
3721
}
3722
3723
// This function is basically a switch over the CFI failure kind, which is
3724
// extracted from CFICheckFailData (1st function argument). Each case is either
3725
// llvm.trap or a call to one of the two runtime handlers, based on
3726
// -fsanitize-trap and -fsanitize-recover settings. Default case (invalid
3727
// failure kind) traps, but this should really never happen. CFICheckFailData
3728
// can be nullptr if the calling module has -fsanitize-trap behavior for this
3729
// check kind; in this case __cfi_check_fail traps as well.
3730
void CodeGenFunction::EmitCfiCheckFail() {
3731
SanitizerScope SanScope(this);
3732
FunctionArgList Args;
3733
ImplicitParamDecl ArgData(getContext(), getContext().VoidPtrTy,
3734
ImplicitParamKind::Other);
3735
ImplicitParamDecl ArgAddr(getContext(), getContext().VoidPtrTy,
3736
ImplicitParamKind::Other);
3737
Args.push_back(&ArgData);
3738
Args.push_back(&ArgAddr);
3739
3740
const CGFunctionInfo &FI =
3741
CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args);
3742
3743
llvm::Function *F = llvm::Function::Create(
3744
llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false),
3745
llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule());
3746
3747
CGM.SetLLVMFunctionAttributes(GlobalDecl(), FI, F, /*IsThunk=*/false);
3748
CGM.SetLLVMFunctionAttributesForDefinition(nullptr, F);
3749
F->setVisibility(llvm::GlobalValue::HiddenVisibility);
3750
3751
StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args,
3752
SourceLocation());
3753
3754
// This function is not affected by NoSanitizeList. This function does
3755
// not have a source location, but "src:*" would still apply. Revert any
3756
// changes to SanOpts made in StartFunction.
3757
SanOpts = CGM.getLangOpts().Sanitize;
3758
3759
llvm::Value *Data =
3760
EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false,
3761
CGM.getContext().VoidPtrTy, ArgData.getLocation());
3762
llvm::Value *Addr =
3763
EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false,
3764
CGM.getContext().VoidPtrTy, ArgAddr.getLocation());
3765
3766
// Data == nullptr means the calling module has trap behaviour for this check.
3767
llvm::Value *DataIsNotNullPtr =
3768
Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy));
3769
EmitTrapCheck(DataIsNotNullPtr, SanitizerHandler::CFICheckFail);
3770
3771
llvm::StructType *SourceLocationTy =
3772
llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty);
3773
llvm::StructType *CfiCheckFailDataTy =
3774
llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy);
3775
3776
llvm::Value *V = Builder.CreateConstGEP2_32(
3777
CfiCheckFailDataTy,
3778
Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0,
3779
0);
3780
3781
Address CheckKindAddr(V, Int8Ty, getIntAlign());
3782
llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr);
3783
3784
llvm::Value *AllVtables = llvm::MetadataAsValue::get(
3785
CGM.getLLVMContext(),
3786
llvm::MDString::get(CGM.getLLVMContext(), "all-vtables"));
3787
llvm::Value *ValidVtable = Builder.CreateZExt(
3788
Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::type_test),
3789
{Addr, AllVtables}),
3790
IntPtrTy);
3791
3792
const std::pair<int, SanitizerMask> CheckKinds[] = {
3793
{CFITCK_VCall, SanitizerKind::CFIVCall},
3794
{CFITCK_NVCall, SanitizerKind::CFINVCall},
3795
{CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast},
3796
{CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast},
3797
{CFITCK_ICall, SanitizerKind::CFIICall}};
3798
3799
SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks;
3800
for (auto CheckKindMaskPair : CheckKinds) {
3801
int Kind = CheckKindMaskPair.first;
3802
SanitizerMask Mask = CheckKindMaskPair.second;
3803
llvm::Value *Cond =
3804
Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind));
3805
if (CGM.getLangOpts().Sanitize.has(Mask))
3806
EmitCheck(std::make_pair(Cond, Mask), SanitizerHandler::CFICheckFail, {},
3807
{Data, Addr, ValidVtable});
3808
else
3809
EmitTrapCheck(Cond, SanitizerHandler::CFICheckFail);
3810
}
3811
3812
FinishFunction();
3813
// The only reference to this function will be created during LTO link.
3814
// Make sure it survives until then.
3815
CGM.addUsedGlobal(F);
3816
}
3817
3818
void CodeGenFunction::EmitUnreachable(SourceLocation Loc) {
3819
if (SanOpts.has(SanitizerKind::Unreachable)) {
3820
SanitizerScope SanScope(this);
3821
EmitCheck(std::make_pair(static_cast<llvm::Value *>(Builder.getFalse()),
3822
SanitizerKind::Unreachable),
3823
SanitizerHandler::BuiltinUnreachable,
3824
EmitCheckSourceLocation(Loc), std::nullopt);
3825
}
3826
Builder.CreateUnreachable();
3827
}
3828
3829
void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked,
3830
SanitizerHandler CheckHandlerID) {
3831
llvm::BasicBlock *Cont = createBasicBlock("cont");
3832
3833
// If we're optimizing, collapse all calls to trap down to just one per
3834
// check-type per function to save on code size.
3835
if ((int)TrapBBs.size() <= CheckHandlerID)
3836
TrapBBs.resize(CheckHandlerID + 1);
3837
3838
llvm::BasicBlock *&TrapBB = TrapBBs[CheckHandlerID];
3839
3840
if (!ClSanitizeDebugDeoptimization &&
3841
CGM.getCodeGenOpts().OptimizationLevel && TrapBB &&
3842
(!CurCodeDecl || !CurCodeDecl->hasAttr<OptimizeNoneAttr>())) {
3843
auto Call = TrapBB->begin();
3844
assert(isa<llvm::CallInst>(Call) && "Expected call in trap BB");
3845
3846
Call->applyMergedLocation(Call->getDebugLoc(),
3847
Builder.getCurrentDebugLocation());
3848
Builder.CreateCondBr(Checked, Cont, TrapBB);
3849
} else {
3850
TrapBB = createBasicBlock("trap");
3851
Builder.CreateCondBr(Checked, Cont, TrapBB);
3852
EmitBlock(TrapBB);
3853
3854
llvm::CallInst *TrapCall = Builder.CreateCall(
3855
CGM.getIntrinsic(llvm::Intrinsic::ubsantrap),
3856
llvm::ConstantInt::get(CGM.Int8Ty,
3857
ClSanitizeDebugDeoptimization
3858
? TrapBB->getParent()->size()
3859
: static_cast<uint64_t>(CheckHandlerID)));
3860
3861
if (!CGM.getCodeGenOpts().TrapFuncName.empty()) {
3862
auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name",
3863
CGM.getCodeGenOpts().TrapFuncName);
3864
TrapCall->addFnAttr(A);
3865
}
3866
TrapCall->setDoesNotReturn();
3867
TrapCall->setDoesNotThrow();
3868
Builder.CreateUnreachable();
3869
}
3870
3871
EmitBlock(Cont);
3872
}
3873
3874
llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) {
3875
llvm::CallInst *TrapCall =
3876
Builder.CreateCall(CGM.getIntrinsic(IntrID));
3877
3878
if (!CGM.getCodeGenOpts().TrapFuncName.empty()) {
3879
auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name",
3880
CGM.getCodeGenOpts().TrapFuncName);
3881
TrapCall->addFnAttr(A);
3882
}
3883
3884
return TrapCall;
3885
}
3886
3887
Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E,
3888
LValueBaseInfo *BaseInfo,
3889
TBAAAccessInfo *TBAAInfo) {
3890
assert(E->getType()->isArrayType() &&
3891
"Array to pointer decay must have array source type!");
3892
3893
// Expressions of array type can't be bitfields or vector elements.
3894
LValue LV = EmitLValue(E);
3895
Address Addr = LV.getAddress();
3896
3897
// If the array type was an incomplete type, we need to make sure
3898
// the decay ends up being the right type.
3899
llvm::Type *NewTy = ConvertType(E->getType());
3900
Addr = Addr.withElementType(NewTy);
3901
3902
// Note that VLA pointers are always decayed, so we don't need to do
3903
// anything here.
3904
if (!E->getType()->isVariableArrayType()) {
3905
assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3906
"Expected pointer to array");
3907
Addr = Builder.CreateConstArrayGEP(Addr, 0, "arraydecay");
3908
}
3909
3910
// The result of this decay conversion points to an array element within the
3911
// base lvalue. However, since TBAA currently does not support representing
3912
// accesses to elements of member arrays, we conservatively represent accesses
3913
// to the pointee object as if it had no any base lvalue specified.
3914
// TODO: Support TBAA for member arrays.
3915
QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType();
3916
if (BaseInfo) *BaseInfo = LV.getBaseInfo();
3917
if (TBAAInfo) *TBAAInfo = CGM.getTBAAAccessInfo(EltType);
3918
3919
return Addr.withElementType(ConvertTypeForMem(EltType));
3920
}
3921
3922
/// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
3923
/// array to pointer, return the array subexpression.
3924
static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
3925
// If this isn't just an array->pointer decay, bail out.
3926
const auto *CE = dyn_cast<CastExpr>(E);
3927
if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay)
3928
return nullptr;
3929
3930
// If this is a decay from variable width array, bail out.
3931
const Expr *SubExpr = CE->getSubExpr();
3932
if (SubExpr->getType()->isVariableArrayType())
3933
return nullptr;
3934
3935
return SubExpr;
3936
}
3937
3938
static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF,
3939
llvm::Type *elemType,
3940
llvm::Value *ptr,
3941
ArrayRef<llvm::Value*> indices,
3942
bool inbounds,
3943
bool signedIndices,
3944
SourceLocation loc,
3945
const llvm::Twine &name = "arrayidx") {
3946
if (inbounds) {
3947
return CGF.EmitCheckedInBoundsGEP(elemType, ptr, indices, signedIndices,
3948
CodeGenFunction::NotSubtraction, loc,
3949
name);
3950
} else {
3951
return CGF.Builder.CreateGEP(elemType, ptr, indices, name);
3952
}
3953
}
3954
3955
static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
3956
ArrayRef<llvm::Value *> indices,
3957
llvm::Type *elementType, bool inbounds,
3958
bool signedIndices, SourceLocation loc,
3959
CharUnits align,
3960
const llvm::Twine &name = "arrayidx") {
3961
if (inbounds) {
3962
return CGF.EmitCheckedInBoundsGEP(addr, indices, elementType, signedIndices,
3963
CodeGenFunction::NotSubtraction, loc,
3964
align, name);
3965
} else {
3966
return CGF.Builder.CreateGEP(addr, indices, elementType, align, name);
3967
}
3968
}
3969
3970
static CharUnits getArrayElementAlign(CharUnits arrayAlign,
3971
llvm::Value *idx,
3972
CharUnits eltSize) {
3973
// If we have a constant index, we can use the exact offset of the
3974
// element we're accessing.
3975
if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) {
3976
CharUnits offset = constantIdx->getZExtValue() * eltSize;
3977
return arrayAlign.alignmentAtOffset(offset);
3978
3979
// Otherwise, use the worst-case alignment for any element.
3980
} else {
3981
return arrayAlign.alignmentOfArrayElement(eltSize);
3982
}
3983
}
3984
3985
static QualType getFixedSizeElementType(const ASTContext &ctx,
3986
const VariableArrayType *vla) {
3987
QualType eltType;
3988
do {
3989
eltType = vla->getElementType();
3990
} while ((vla = ctx.getAsVariableArrayType(eltType)));
3991
return eltType;
3992
}
3993
3994
static bool hasBPFPreserveStaticOffset(const RecordDecl *D) {
3995
return D && D->hasAttr<BPFPreserveStaticOffsetAttr>();
3996
}
3997
3998
static bool hasBPFPreserveStaticOffset(const Expr *E) {
3999
if (!E)
4000
return false;
4001
QualType PointeeType = E->getType()->getPointeeType();
4002
if (PointeeType.isNull())
4003
return false;
4004
if (const auto *BaseDecl = PointeeType->getAsRecordDecl())
4005
return hasBPFPreserveStaticOffset(BaseDecl);
4006
return false;
4007
}
4008
4009
// Wraps Addr with a call to llvm.preserve.static.offset intrinsic.
4010
static Address wrapWithBPFPreserveStaticOffset(CodeGenFunction &CGF,
4011
Address &Addr) {
4012
if (!CGF.getTarget().getTriple().isBPF())
4013
return Addr;
4014
4015
llvm::Function *Fn =
4016
CGF.CGM.getIntrinsic(llvm::Intrinsic::preserve_static_offset);
4017
llvm::CallInst *Call = CGF.Builder.CreateCall(Fn, {Addr.emitRawPointer(CGF)});
4018
return Address(Call, Addr.getElementType(), Addr.getAlignment());
4019
}
4020
4021
/// Given an array base, check whether its member access belongs to a record
4022
/// with preserve_access_index attribute or not.
4023
static bool IsPreserveAIArrayBase(CodeGenFunction &CGF, const Expr *ArrayBase) {
4024
if (!ArrayBase || !CGF.getDebugInfo())
4025
return false;
4026
4027
// Only support base as either a MemberExpr or DeclRefExpr.
4028
// DeclRefExpr to cover cases like:
4029
// struct s { int a; int b[10]; };
4030
// struct s *p;
4031
// p[1].a
4032
// p[1] will generate a DeclRefExpr and p[1].a is a MemberExpr.
4033
// p->b[5] is a MemberExpr example.
4034
const Expr *E = ArrayBase->IgnoreImpCasts();
4035
if (const auto *ME = dyn_cast<MemberExpr>(E))
4036
return ME->getMemberDecl()->hasAttr<BPFPreserveAccessIndexAttr>();
4037
4038
if (const auto *DRE = dyn_cast<DeclRefExpr>(E)) {
4039
const auto *VarDef = dyn_cast<VarDecl>(DRE->getDecl());
4040
if (!VarDef)
4041
return false;
4042
4043
const auto *PtrT = VarDef->getType()->getAs<PointerType>();
4044
if (!PtrT)
4045
return false;
4046
4047
const auto *PointeeT = PtrT->getPointeeType()
4048
->getUnqualifiedDesugaredType();
4049
if (const auto *RecT = dyn_cast<RecordType>(PointeeT))
4050
return RecT->getDecl()->hasAttr<BPFPreserveAccessIndexAttr>();
4051
return false;
4052
}
4053
4054
return false;
4055
}
4056
4057
static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
4058
ArrayRef<llvm::Value *> indices,
4059
QualType eltType, bool inbounds,
4060
bool signedIndices, SourceLocation loc,
4061
QualType *arrayType = nullptr,
4062
const Expr *Base = nullptr,
4063
const llvm::Twine &name = "arrayidx") {
4064
// All the indices except that last must be zero.
4065
#ifndef NDEBUG
4066
for (auto *idx : indices.drop_back())
4067
assert(isa<llvm::ConstantInt>(idx) &&
4068
cast<llvm::ConstantInt>(idx)->isZero());
4069
#endif
4070
4071
// Determine the element size of the statically-sized base. This is
4072
// the thing that the indices are expressed in terms of.
4073
if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) {
4074
eltType = getFixedSizeElementType(CGF.getContext(), vla);
4075
}
4076
4077
// We can use that to compute the best alignment of the element.
4078
CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType);
4079
CharUnits eltAlign =
4080
getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize);
4081
4082
if (hasBPFPreserveStaticOffset(Base))
4083
addr = wrapWithBPFPreserveStaticOffset(CGF, addr);
4084
4085
llvm::Value *eltPtr;
4086
auto LastIndex = dyn_cast<llvm::ConstantInt>(indices.back());
4087
if (!LastIndex ||
4088
(!CGF.IsInPreservedAIRegion && !IsPreserveAIArrayBase(CGF, Base))) {
4089
addr = emitArraySubscriptGEP(CGF, addr, indices,
4090
CGF.ConvertTypeForMem(eltType), inbounds,
4091
signedIndices, loc, eltAlign, name);
4092
return addr;
4093
} else {
4094
// Remember the original array subscript for bpf target
4095
unsigned idx = LastIndex->getZExtValue();
4096
llvm::DIType *DbgInfo = nullptr;
4097
if (arrayType)
4098
DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType(*arrayType, loc);
4099
eltPtr = CGF.Builder.CreatePreserveArrayAccessIndex(
4100
addr.getElementType(), addr.emitRawPointer(CGF), indices.size() - 1,
4101
idx, DbgInfo);
4102
}
4103
4104
return Address(eltPtr, CGF.ConvertTypeForMem(eltType), eltAlign);
4105
}
4106
4107
/// The offset of a field from the beginning of the record.
4108
static bool getFieldOffsetInBits(CodeGenFunction &CGF, const RecordDecl *RD,
4109
const FieldDecl *FD, int64_t &Offset) {
4110
ASTContext &Ctx = CGF.getContext();
4111
const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD);
4112
unsigned FieldNo = 0;
4113
4114
for (const Decl *D : RD->decls()) {
4115
if (const auto *Record = dyn_cast<RecordDecl>(D))
4116
if (getFieldOffsetInBits(CGF, Record, FD, Offset)) {
4117
Offset += Layout.getFieldOffset(FieldNo);
4118
return true;
4119
}
4120
4121
if (const auto *Field = dyn_cast<FieldDecl>(D))
4122
if (FD == Field) {
4123
Offset += Layout.getFieldOffset(FieldNo);
4124
return true;
4125
}
4126
4127
if (isa<FieldDecl>(D))
4128
++FieldNo;
4129
}
4130
4131
return false;
4132
}
4133
4134
/// Returns the relative offset difference between \p FD1 and \p FD2.
4135
/// \code
4136
/// offsetof(struct foo, FD1) - offsetof(struct foo, FD2)
4137
/// \endcode
4138
/// Both fields must be within the same struct.
4139
static std::optional<int64_t> getOffsetDifferenceInBits(CodeGenFunction &CGF,
4140
const FieldDecl *FD1,
4141
const FieldDecl *FD2) {
4142
const RecordDecl *FD1OuterRec =
4143
FD1->getParent()->getOuterLexicalRecordContext();
4144
const RecordDecl *FD2OuterRec =
4145
FD2->getParent()->getOuterLexicalRecordContext();
4146
4147
if (FD1OuterRec != FD2OuterRec)
4148
// Fields must be within the same RecordDecl.
4149
return std::optional<int64_t>();
4150
4151
int64_t FD1Offset = 0;
4152
if (!getFieldOffsetInBits(CGF, FD1OuterRec, FD1, FD1Offset))
4153
return std::optional<int64_t>();
4154
4155
int64_t FD2Offset = 0;
4156
if (!getFieldOffsetInBits(CGF, FD2OuterRec, FD2, FD2Offset))
4157
return std::optional<int64_t>();
4158
4159
return std::make_optional<int64_t>(FD1Offset - FD2Offset);
4160
}
4161
4162
LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
4163
bool Accessed) {
4164
// The index must always be an integer, which is not an aggregate. Emit it
4165
// in lexical order (this complexity is, sadly, required by C++17).
4166
llvm::Value *IdxPre =
4167
(E->getLHS() == E->getIdx()) ? EmitScalarExpr(E->getIdx()) : nullptr;
4168
bool SignedIndices = false;
4169
auto EmitIdxAfterBase = [&, IdxPre](bool Promote) -> llvm::Value * {
4170
auto *Idx = IdxPre;
4171
if (E->getLHS() != E->getIdx()) {
4172
assert(E->getRHS() == E->getIdx() && "index was neither LHS nor RHS");
4173
Idx = EmitScalarExpr(E->getIdx());
4174
}
4175
4176
QualType IdxTy = E->getIdx()->getType();
4177
bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType();
4178
SignedIndices |= IdxSigned;
4179
4180
if (SanOpts.has(SanitizerKind::ArrayBounds))
4181
EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed);
4182
4183
// Extend or truncate the index type to 32 or 64-bits.
4184
if (Promote && Idx->getType() != IntPtrTy)
4185
Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
4186
4187
return Idx;
4188
};
4189
IdxPre = nullptr;
4190
4191
// If the base is a vector type, then we are forming a vector element lvalue
4192
// with this subscript.
4193
if (E->getBase()->getType()->isSubscriptableVectorType() &&
4194
!isa<ExtVectorElementExpr>(E->getBase())) {
4195
// Emit the vector as an lvalue to get its address.
4196
LValue LHS = EmitLValue(E->getBase());
4197
auto *Idx = EmitIdxAfterBase(/*Promote*/false);
4198
assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
4199
return LValue::MakeVectorElt(LHS.getAddress(), Idx, E->getBase()->getType(),
4200
LHS.getBaseInfo(), TBAAAccessInfo());
4201
}
4202
4203
// All the other cases basically behave like simple offsetting.
4204
4205
// Handle the extvector case we ignored above.
4206
if (isa<ExtVectorElementExpr>(E->getBase())) {
4207
LValue LV = EmitLValue(E->getBase());
4208
auto *Idx = EmitIdxAfterBase(/*Promote*/true);
4209
Address Addr = EmitExtVectorElementLValue(LV);
4210
4211
QualType EltType = LV.getType()->castAs<VectorType>()->getElementType();
4212
Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true,
4213
SignedIndices, E->getExprLoc());
4214
return MakeAddrLValue(Addr, EltType, LV.getBaseInfo(),
4215
CGM.getTBAAInfoForSubobject(LV, EltType));
4216
}
4217
4218
LValueBaseInfo EltBaseInfo;
4219
TBAAAccessInfo EltTBAAInfo;
4220
Address Addr = Address::invalid();
4221
if (const VariableArrayType *vla =
4222
getContext().getAsVariableArrayType(E->getType())) {
4223
// The base must be a pointer, which is not an aggregate. Emit
4224
// it. It needs to be emitted first in case it's what captures
4225
// the VLA bounds.
4226
Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
4227
auto *Idx = EmitIdxAfterBase(/*Promote*/true);
4228
4229
// The element count here is the total number of non-VLA elements.
4230
llvm::Value *numElements = getVLASize(vla).NumElts;
4231
4232
// Effectively, the multiply by the VLA size is part of the GEP.
4233
// GEP indexes are signed, and scaling an index isn't permitted to
4234
// signed-overflow, so we use the same semantics for our explicit
4235
// multiply. We suppress this if overflow is not undefined behavior.
4236
if (getLangOpts().isSignedOverflowDefined()) {
4237
Idx = Builder.CreateMul(Idx, numElements);
4238
} else {
4239
Idx = Builder.CreateNSWMul(Idx, numElements);
4240
}
4241
4242
Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(),
4243
!getLangOpts().isSignedOverflowDefined(),
4244
SignedIndices, E->getExprLoc());
4245
4246
} else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
4247
// Indexing over an interface, as in "NSString *P; P[4];"
4248
4249
// Emit the base pointer.
4250
Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
4251
auto *Idx = EmitIdxAfterBase(/*Promote*/true);
4252
4253
CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT);
4254
llvm::Value *InterfaceSizeVal =
4255
llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity());
4256
4257
llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal);
4258
4259
// We don't necessarily build correct LLVM struct types for ObjC
4260
// interfaces, so we can't rely on GEP to do this scaling
4261
// correctly, so we need to cast to i8*. FIXME: is this actually
4262
// true? A lot of other things in the fragile ABI would break...
4263
llvm::Type *OrigBaseElemTy = Addr.getElementType();
4264
4265
// Do the GEP.
4266
CharUnits EltAlign =
4267
getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize);
4268
llvm::Value *EltPtr =
4269
emitArraySubscriptGEP(*this, Int8Ty, Addr.emitRawPointer(*this),
4270
ScaledIdx, false, SignedIndices, E->getExprLoc());
4271
Addr = Address(EltPtr, OrigBaseElemTy, EltAlign);
4272
} else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
4273
// If this is A[i] where A is an array, the frontend will have decayed the
4274
// base to be a ArrayToPointerDecay implicit cast. While correct, it is
4275
// inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
4276
// "gep x, i" here. Emit one "gep A, 0, i".
4277
assert(Array->getType()->isArrayType() &&
4278
"Array to pointer decay must have array source type!");
4279
LValue ArrayLV;
4280
// For simple multidimensional array indexing, set the 'accessed' flag for
4281
// better bounds-checking of the base expression.
4282
if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
4283
ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
4284
else
4285
ArrayLV = EmitLValue(Array);
4286
auto *Idx = EmitIdxAfterBase(/*Promote*/true);
4287
4288
if (SanOpts.has(SanitizerKind::ArrayBounds)) {
4289
// If the array being accessed has a "counted_by" attribute, generate
4290
// bounds checking code. The "count" field is at the top level of the
4291
// struct or in an anonymous struct, that's also at the top level. Future
4292
// expansions may allow the "count" to reside at any place in the struct,
4293
// but the value of "counted_by" will be a "simple" path to the count,
4294
// i.e. "a.b.count", so we shouldn't need the full force of EmitLValue or
4295
// similar to emit the correct GEP.
4296
const LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel =
4297
getLangOpts().getStrictFlexArraysLevel();
4298
4299
if (const auto *ME = dyn_cast<MemberExpr>(Array);
4300
ME &&
4301
ME->isFlexibleArrayMemberLike(getContext(), StrictFlexArraysLevel) &&
4302
ME->getMemberDecl()->getType()->isCountAttributedType()) {
4303
const FieldDecl *FAMDecl = dyn_cast<FieldDecl>(ME->getMemberDecl());
4304
if (const FieldDecl *CountFD = FindCountedByField(FAMDecl)) {
4305
if (std::optional<int64_t> Diff =
4306
getOffsetDifferenceInBits(*this, CountFD, FAMDecl)) {
4307
CharUnits OffsetDiff = CGM.getContext().toCharUnitsFromBits(*Diff);
4308
4309
// Create a GEP with a byte offset between the FAM and count and
4310
// use that to load the count value.
4311
Addr = Builder.CreatePointerBitCastOrAddrSpaceCast(
4312
ArrayLV.getAddress(), Int8PtrTy, Int8Ty);
4313
4314
llvm::Type *CountTy = ConvertType(CountFD->getType());
4315
llvm::Value *Res = Builder.CreateInBoundsGEP(
4316
Int8Ty, Addr.emitRawPointer(*this),
4317
Builder.getInt32(OffsetDiff.getQuantity()), ".counted_by.gep");
4318
Res = Builder.CreateAlignedLoad(CountTy, Res, getIntAlign(),
4319
".counted_by.load");
4320
4321
// Now emit the bounds checking.
4322
EmitBoundsCheckImpl(E, Res, Idx, E->getIdx()->getType(),
4323
Array->getType(), Accessed);
4324
}
4325
}
4326
}
4327
}
4328
4329
// Propagate the alignment from the array itself to the result.
4330
QualType arrayType = Array->getType();
4331
Addr = emitArraySubscriptGEP(
4332
*this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
4333
E->getType(), !getLangOpts().isSignedOverflowDefined(), SignedIndices,
4334
E->getExprLoc(), &arrayType, E->getBase());
4335
EltBaseInfo = ArrayLV.getBaseInfo();
4336
EltTBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, E->getType());
4337
} else {
4338
// The base must be a pointer; emit it with an estimate of its alignment.
4339
Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
4340
auto *Idx = EmitIdxAfterBase(/*Promote*/true);
4341
QualType ptrType = E->getBase()->getType();
4342
Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(),
4343
!getLangOpts().isSignedOverflowDefined(),
4344
SignedIndices, E->getExprLoc(), &ptrType,
4345
E->getBase());
4346
}
4347
4348
LValue LV = MakeAddrLValue(Addr, E->getType(), EltBaseInfo, EltTBAAInfo);
4349
4350
if (getLangOpts().ObjC &&
4351
getLangOpts().getGC() != LangOptions::NonGC) {
4352
LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
4353
setObjCGCLValueClass(getContext(), E, LV);
4354
}
4355
return LV;
4356
}
4357
4358
LValue CodeGenFunction::EmitMatrixSubscriptExpr(const MatrixSubscriptExpr *E) {
4359
assert(
4360
!E->isIncomplete() &&
4361
"incomplete matrix subscript expressions should be rejected during Sema");
4362
LValue Base = EmitLValue(E->getBase());
4363
llvm::Value *RowIdx = EmitScalarExpr(E->getRowIdx());
4364
llvm::Value *ColIdx = EmitScalarExpr(E->getColumnIdx());
4365
llvm::Value *NumRows = Builder.getIntN(
4366
RowIdx->getType()->getScalarSizeInBits(),
4367
E->getBase()->getType()->castAs<ConstantMatrixType>()->getNumRows());
4368
llvm::Value *FinalIdx =
4369
Builder.CreateAdd(Builder.CreateMul(ColIdx, NumRows), RowIdx);
4370
return LValue::MakeMatrixElt(
4371
MaybeConvertMatrixAddress(Base.getAddress(), *this), FinalIdx,
4372
E->getBase()->getType(), Base.getBaseInfo(), TBAAAccessInfo());
4373
}
4374
4375
static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base,
4376
LValueBaseInfo &BaseInfo,
4377
TBAAAccessInfo &TBAAInfo,
4378
QualType BaseTy, QualType ElTy,
4379
bool IsLowerBound) {
4380
LValue BaseLVal;
4381
if (auto *ASE = dyn_cast<ArraySectionExpr>(Base->IgnoreParenImpCasts())) {
4382
BaseLVal = CGF.EmitArraySectionExpr(ASE, IsLowerBound);
4383
if (BaseTy->isArrayType()) {
4384
Address Addr = BaseLVal.getAddress();
4385
BaseInfo = BaseLVal.getBaseInfo();
4386
4387
// If the array type was an incomplete type, we need to make sure
4388
// the decay ends up being the right type.
4389
llvm::Type *NewTy = CGF.ConvertType(BaseTy);
4390
Addr = Addr.withElementType(NewTy);
4391
4392
// Note that VLA pointers are always decayed, so we don't need to do
4393
// anything here.
4394
if (!BaseTy->isVariableArrayType()) {
4395
assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
4396
"Expected pointer to array");
4397
Addr = CGF.Builder.CreateConstArrayGEP(Addr, 0, "arraydecay");
4398
}
4399
4400
return Addr.withElementType(CGF.ConvertTypeForMem(ElTy));
4401
}
4402
LValueBaseInfo TypeBaseInfo;
4403
TBAAAccessInfo TypeTBAAInfo;
4404
CharUnits Align =
4405
CGF.CGM.getNaturalTypeAlignment(ElTy, &TypeBaseInfo, &TypeTBAAInfo);
4406
BaseInfo.mergeForCast(TypeBaseInfo);
4407
TBAAInfo = CGF.CGM.mergeTBAAInfoForCast(TBAAInfo, TypeTBAAInfo);
4408
return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress()),
4409
CGF.ConvertTypeForMem(ElTy), Align);
4410
}
4411
return CGF.EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo);
4412
}
4413
4414
LValue CodeGenFunction::EmitArraySectionExpr(const ArraySectionExpr *E,
4415
bool IsLowerBound) {
4416
4417
assert(!E->isOpenACCArraySection() &&
4418
"OpenACC Array section codegen not implemented");
4419
4420
QualType BaseTy = ArraySectionExpr::getBaseOriginalType(E->getBase());
4421
QualType ResultExprTy;
4422
if (auto *AT = getContext().getAsArrayType(BaseTy))
4423
ResultExprTy = AT->getElementType();
4424
else
4425
ResultExprTy = BaseTy->getPointeeType();
4426
llvm::Value *Idx = nullptr;
4427
if (IsLowerBound || E->getColonLocFirst().isInvalid()) {
4428
// Requesting lower bound or upper bound, but without provided length and
4429
// without ':' symbol for the default length -> length = 1.
4430
// Idx = LowerBound ?: 0;
4431
if (auto *LowerBound = E->getLowerBound()) {
4432
Idx = Builder.CreateIntCast(
4433
EmitScalarExpr(LowerBound), IntPtrTy,
4434
LowerBound->getType()->hasSignedIntegerRepresentation());
4435
} else
4436
Idx = llvm::ConstantInt::getNullValue(IntPtrTy);
4437
} else {
4438
// Try to emit length or lower bound as constant. If this is possible, 1
4439
// is subtracted from constant length or lower bound. Otherwise, emit LLVM
4440
// IR (LB + Len) - 1.
4441
auto &C = CGM.getContext();
4442
auto *Length = E->getLength();
4443
llvm::APSInt ConstLength;
4444
if (Length) {
4445
// Idx = LowerBound + Length - 1;
4446
if (std::optional<llvm::APSInt> CL = Length->getIntegerConstantExpr(C)) {
4447
ConstLength = CL->zextOrTrunc(PointerWidthInBits);
4448
Length = nullptr;
4449
}
4450
auto *LowerBound = E->getLowerBound();
4451
llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false);
4452
if (LowerBound) {
4453
if (std::optional<llvm::APSInt> LB =
4454
LowerBound->getIntegerConstantExpr(C)) {
4455
ConstLowerBound = LB->zextOrTrunc(PointerWidthInBits);
4456
LowerBound = nullptr;
4457
}
4458
}
4459
if (!Length)
4460
--ConstLength;
4461
else if (!LowerBound)
4462
--ConstLowerBound;
4463
4464
if (Length || LowerBound) {
4465
auto *LowerBoundVal =
4466
LowerBound
4467
? Builder.CreateIntCast(
4468
EmitScalarExpr(LowerBound), IntPtrTy,
4469
LowerBound->getType()->hasSignedIntegerRepresentation())
4470
: llvm::ConstantInt::get(IntPtrTy, ConstLowerBound);
4471
auto *LengthVal =
4472
Length
4473
? Builder.CreateIntCast(
4474
EmitScalarExpr(Length), IntPtrTy,
4475
Length->getType()->hasSignedIntegerRepresentation())
4476
: llvm::ConstantInt::get(IntPtrTy, ConstLength);
4477
Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len",
4478
/*HasNUW=*/false,
4479
!getLangOpts().isSignedOverflowDefined());
4480
if (Length && LowerBound) {
4481
Idx = Builder.CreateSub(
4482
Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1",
4483
/*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
4484
}
4485
} else
4486
Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound);
4487
} else {
4488
// Idx = ArraySize - 1;
4489
QualType ArrayTy = BaseTy->isPointerType()
4490
? E->getBase()->IgnoreParenImpCasts()->getType()
4491
: BaseTy;
4492
if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) {
4493
Length = VAT->getSizeExpr();
4494
if (std::optional<llvm::APSInt> L = Length->getIntegerConstantExpr(C)) {
4495
ConstLength = *L;
4496
Length = nullptr;
4497
}
4498
} else {
4499
auto *CAT = C.getAsConstantArrayType(ArrayTy);
4500
assert(CAT && "unexpected type for array initializer");
4501
ConstLength = CAT->getSize();
4502
}
4503
if (Length) {
4504
auto *LengthVal = Builder.CreateIntCast(
4505
EmitScalarExpr(Length), IntPtrTy,
4506
Length->getType()->hasSignedIntegerRepresentation());
4507
Idx = Builder.CreateSub(
4508
LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1",
4509
/*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
4510
} else {
4511
ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
4512
--ConstLength;
4513
Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength);
4514
}
4515
}
4516
}
4517
assert(Idx);
4518
4519
Address EltPtr = Address::invalid();
4520
LValueBaseInfo BaseInfo;
4521
TBAAAccessInfo TBAAInfo;
4522
if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) {
4523
// The base must be a pointer, which is not an aggregate. Emit
4524
// it. It needs to be emitted first in case it's what captures
4525
// the VLA bounds.
4526
Address Base =
4527
emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, TBAAInfo,
4528
BaseTy, VLA->getElementType(), IsLowerBound);
4529
// The element count here is the total number of non-VLA elements.
4530
llvm::Value *NumElements = getVLASize(VLA).NumElts;
4531
4532
// Effectively, the multiply by the VLA size is part of the GEP.
4533
// GEP indexes are signed, and scaling an index isn't permitted to
4534
// signed-overflow, so we use the same semantics for our explicit
4535
// multiply. We suppress this if overflow is not undefined behavior.
4536
if (getLangOpts().isSignedOverflowDefined())
4537
Idx = Builder.CreateMul(Idx, NumElements);
4538
else
4539
Idx = Builder.CreateNSWMul(Idx, NumElements);
4540
EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(),
4541
!getLangOpts().isSignedOverflowDefined(),
4542
/*signedIndices=*/false, E->getExprLoc());
4543
} else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
4544
// If this is A[i] where A is an array, the frontend will have decayed the
4545
// base to be a ArrayToPointerDecay implicit cast. While correct, it is
4546
// inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
4547
// "gep x, i" here. Emit one "gep A, 0, i".
4548
assert(Array->getType()->isArrayType() &&
4549
"Array to pointer decay must have array source type!");
4550
LValue ArrayLV;
4551
// For simple multidimensional array indexing, set the 'accessed' flag for
4552
// better bounds-checking of the base expression.
4553
if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
4554
ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
4555
else
4556
ArrayLV = EmitLValue(Array);
4557
4558
// Propagate the alignment from the array itself to the result.
4559
EltPtr = emitArraySubscriptGEP(
4560
*this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
4561
ResultExprTy, !getLangOpts().isSignedOverflowDefined(),
4562
/*signedIndices=*/false, E->getExprLoc());
4563
BaseInfo = ArrayLV.getBaseInfo();
4564
TBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, ResultExprTy);
4565
} else {
4566
Address Base =
4567
emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, TBAAInfo, BaseTy,
4568
ResultExprTy, IsLowerBound);
4569
EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy,
4570
!getLangOpts().isSignedOverflowDefined(),
4571
/*signedIndices=*/false, E->getExprLoc());
4572
}
4573
4574
return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo, TBAAInfo);
4575
}
4576
4577
LValue CodeGenFunction::
4578
EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
4579
// Emit the base vector as an l-value.
4580
LValue Base;
4581
4582
// ExtVectorElementExpr's base can either be a vector or pointer to vector.
4583
if (E->isArrow()) {
4584
// If it is a pointer to a vector, emit the address and form an lvalue with
4585
// it.
4586
LValueBaseInfo BaseInfo;
4587
TBAAAccessInfo TBAAInfo;
4588
Address Ptr = EmitPointerWithAlignment(E->getBase(), &BaseInfo, &TBAAInfo);
4589
const auto *PT = E->getBase()->getType()->castAs<PointerType>();
4590
Base = MakeAddrLValue(Ptr, PT->getPointeeType(), BaseInfo, TBAAInfo);
4591
Base.getQuals().removeObjCGCAttr();
4592
} else if (E->getBase()->isGLValue()) {
4593
// Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
4594
// emit the base as an lvalue.
4595
assert(E->getBase()->getType()->isVectorType());
4596
Base = EmitLValue(E->getBase());
4597
} else {
4598
// Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
4599
assert(E->getBase()->getType()->isVectorType() &&
4600
"Result must be a vector");
4601
llvm::Value *Vec = EmitScalarExpr(E->getBase());
4602
4603
// Store the vector to memory (because LValue wants an address).
4604
Address VecMem = CreateMemTemp(E->getBase()->getType());
4605
Builder.CreateStore(Vec, VecMem);
4606
Base = MakeAddrLValue(VecMem, E->getBase()->getType(),
4607
AlignmentSource::Decl);
4608
}
4609
4610
QualType type =
4611
E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers());
4612
4613
// Encode the element access list into a vector of unsigned indices.
4614
SmallVector<uint32_t, 4> Indices;
4615
E->getEncodedElementAccess(Indices);
4616
4617
if (Base.isSimple()) {
4618
llvm::Constant *CV =
4619
llvm::ConstantDataVector::get(getLLVMContext(), Indices);
4620
return LValue::MakeExtVectorElt(Base.getAddress(), CV, type,
4621
Base.getBaseInfo(), TBAAAccessInfo());
4622
}
4623
assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
4624
4625
llvm::Constant *BaseElts = Base.getExtVectorElts();
4626
SmallVector<llvm::Constant *, 4> CElts;
4627
4628
for (unsigned i = 0, e = Indices.size(); i != e; ++i)
4629
CElts.push_back(BaseElts->getAggregateElement(Indices[i]));
4630
llvm::Constant *CV = llvm::ConstantVector::get(CElts);
4631
return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type,
4632
Base.getBaseInfo(), TBAAAccessInfo());
4633
}
4634
4635
LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
4636
if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, E)) {
4637
EmitIgnoredExpr(E->getBase());
4638
return EmitDeclRefLValue(DRE);
4639
}
4640
4641
Expr *BaseExpr = E->getBase();
4642
// If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
4643
LValue BaseLV;
4644
if (E->isArrow()) {
4645
LValueBaseInfo BaseInfo;
4646
TBAAAccessInfo TBAAInfo;
4647
Address Addr = EmitPointerWithAlignment(BaseExpr, &BaseInfo, &TBAAInfo);
4648
QualType PtrTy = BaseExpr->getType()->getPointeeType();
4649
SanitizerSet SkippedChecks;
4650
bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr);
4651
if (IsBaseCXXThis)
4652
SkippedChecks.set(SanitizerKind::Alignment, true);
4653
if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr))
4654
SkippedChecks.set(SanitizerKind::Null, true);
4655
EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr, PtrTy,
4656
/*Alignment=*/CharUnits::Zero(), SkippedChecks);
4657
BaseLV = MakeAddrLValue(Addr, PtrTy, BaseInfo, TBAAInfo);
4658
} else
4659
BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess);
4660
4661
NamedDecl *ND = E->getMemberDecl();
4662
if (auto *Field = dyn_cast<FieldDecl>(ND)) {
4663
LValue LV = EmitLValueForField(BaseLV, Field);
4664
setObjCGCLValueClass(getContext(), E, LV);
4665
if (getLangOpts().OpenMP) {
4666
// If the member was explicitly marked as nontemporal, mark it as
4667
// nontemporal. If the base lvalue is marked as nontemporal, mark access
4668
// to children as nontemporal too.
4669
if ((IsWrappedCXXThis(BaseExpr) &&
4670
CGM.getOpenMPRuntime().isNontemporalDecl(Field)) ||
4671
BaseLV.isNontemporal())
4672
LV.setNontemporal(/*Value=*/true);
4673
}
4674
return LV;
4675
}
4676
4677
if (const auto *FD = dyn_cast<FunctionDecl>(ND))
4678
return EmitFunctionDeclLValue(*this, E, FD);
4679
4680
llvm_unreachable("Unhandled member declaration!");
4681
}
4682
4683
/// Given that we are currently emitting a lambda, emit an l-value for
4684
/// one of its members.
4685
///
4686
LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field,
4687
llvm::Value *ThisValue) {
4688
bool HasExplicitObjectParameter = false;
4689
const auto *MD = dyn_cast_if_present<CXXMethodDecl>(CurCodeDecl);
4690
if (MD) {
4691
HasExplicitObjectParameter = MD->isExplicitObjectMemberFunction();
4692
assert(MD->getParent()->isLambda());
4693
assert(MD->getParent() == Field->getParent());
4694
}
4695
LValue LambdaLV;
4696
if (HasExplicitObjectParameter) {
4697
const VarDecl *D = cast<CXXMethodDecl>(CurCodeDecl)->getParamDecl(0);
4698
auto It = LocalDeclMap.find(D);
4699
assert(It != LocalDeclMap.end() && "explicit parameter not loaded?");
4700
Address AddrOfExplicitObject = It->getSecond();
4701
if (D->getType()->isReferenceType())
4702
LambdaLV = EmitLoadOfReferenceLValue(AddrOfExplicitObject, D->getType(),
4703
AlignmentSource::Decl);
4704
else
4705
LambdaLV = MakeAddrLValue(AddrOfExplicitObject,
4706
D->getType().getNonReferenceType());
4707
4708
// Make sure we have an lvalue to the lambda itself and not a derived class.
4709
auto *ThisTy = D->getType().getNonReferenceType()->getAsCXXRecordDecl();
4710
auto *LambdaTy = cast<CXXRecordDecl>(Field->getParent());
4711
if (ThisTy != LambdaTy) {
4712
const CXXCastPath &BasePathArray = getContext().LambdaCastPaths.at(MD);
4713
Address Base = GetAddressOfBaseClass(
4714
LambdaLV.getAddress(), ThisTy, BasePathArray.begin(),
4715
BasePathArray.end(), /*NullCheckValue=*/false, SourceLocation());
4716
LambdaLV = MakeAddrLValue(Base, QualType{LambdaTy->getTypeForDecl(), 0});
4717
}
4718
} else {
4719
QualType LambdaTagType = getContext().getTagDeclType(Field->getParent());
4720
LambdaLV = MakeNaturalAlignAddrLValue(ThisValue, LambdaTagType);
4721
}
4722
return EmitLValueForField(LambdaLV, Field);
4723
}
4724
4725
LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) {
4726
return EmitLValueForLambdaField(Field, CXXABIThisValue);
4727
}
4728
4729
/// Get the field index in the debug info. The debug info structure/union
4730
/// will ignore the unnamed bitfields.
4731
unsigned CodeGenFunction::getDebugInfoFIndex(const RecordDecl *Rec,
4732
unsigned FieldIndex) {
4733
unsigned I = 0, Skipped = 0;
4734
4735
for (auto *F : Rec->getDefinition()->fields()) {
4736
if (I == FieldIndex)
4737
break;
4738
if (F->isUnnamedBitField())
4739
Skipped++;
4740
I++;
4741
}
4742
4743
return FieldIndex - Skipped;
4744
}
4745
4746
/// Get the address of a zero-sized field within a record. The resulting
4747
/// address doesn't necessarily have the right type.
4748
static Address emitAddrOfZeroSizeField(CodeGenFunction &CGF, Address Base,
4749
const FieldDecl *Field) {
4750
CharUnits Offset = CGF.getContext().toCharUnitsFromBits(
4751
CGF.getContext().getFieldOffset(Field));
4752
if (Offset.isZero())
4753
return Base;
4754
Base = Base.withElementType(CGF.Int8Ty);
4755
return CGF.Builder.CreateConstInBoundsByteGEP(Base, Offset);
4756
}
4757
4758
/// Drill down to the storage of a field without walking into
4759
/// reference types.
4760
///
4761
/// The resulting address doesn't necessarily have the right type.
4762
static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base,
4763
const FieldDecl *field) {
4764
if (isEmptyFieldForLayout(CGF.getContext(), field))
4765
return emitAddrOfZeroSizeField(CGF, base, field);
4766
4767
const RecordDecl *rec = field->getParent();
4768
4769
unsigned idx =
4770
CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
4771
4772
return CGF.Builder.CreateStructGEP(base, idx, field->getName());
4773
}
4774
4775
static Address emitPreserveStructAccess(CodeGenFunction &CGF, LValue base,
4776
Address addr, const FieldDecl *field) {
4777
const RecordDecl *rec = field->getParent();
4778
llvm::DIType *DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType(
4779
base.getType(), rec->getLocation());
4780
4781
unsigned idx =
4782
CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
4783
4784
return CGF.Builder.CreatePreserveStructAccessIndex(
4785
addr, idx, CGF.getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo);
4786
}
4787
4788
static bool hasAnyVptr(const QualType Type, const ASTContext &Context) {
4789
const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl();
4790
if (!RD)
4791
return false;
4792
4793
if (RD->isDynamicClass())
4794
return true;
4795
4796
for (const auto &Base : RD->bases())
4797
if (hasAnyVptr(Base.getType(), Context))
4798
return true;
4799
4800
for (const FieldDecl *Field : RD->fields())
4801
if (hasAnyVptr(Field->getType(), Context))
4802
return true;
4803
4804
return false;
4805
}
4806
4807
LValue CodeGenFunction::EmitLValueForField(LValue base,
4808
const FieldDecl *field) {
4809
LValueBaseInfo BaseInfo = base.getBaseInfo();
4810
4811
if (field->isBitField()) {
4812
const CGRecordLayout &RL =
4813
CGM.getTypes().getCGRecordLayout(field->getParent());
4814
const CGBitFieldInfo &Info = RL.getBitFieldInfo(field);
4815
const bool UseVolatile = isAAPCS(CGM.getTarget()) &&
4816
CGM.getCodeGenOpts().AAPCSBitfieldWidth &&
4817
Info.VolatileStorageSize != 0 &&
4818
field->getType()
4819
.withCVRQualifiers(base.getVRQualifiers())
4820
.isVolatileQualified();
4821
Address Addr = base.getAddress();
4822
unsigned Idx = RL.getLLVMFieldNo(field);
4823
const RecordDecl *rec = field->getParent();
4824
if (hasBPFPreserveStaticOffset(rec))
4825
Addr = wrapWithBPFPreserveStaticOffset(*this, Addr);
4826
if (!UseVolatile) {
4827
if (!IsInPreservedAIRegion &&
4828
(!getDebugInfo() || !rec->hasAttr<BPFPreserveAccessIndexAttr>())) {
4829
if (Idx != 0)
4830
// For structs, we GEP to the field that the record layout suggests.
4831
Addr = Builder.CreateStructGEP(Addr, Idx, field->getName());
4832
} else {
4833
llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateRecordType(
4834
getContext().getRecordType(rec), rec->getLocation());
4835
Addr = Builder.CreatePreserveStructAccessIndex(
4836
Addr, Idx, getDebugInfoFIndex(rec, field->getFieldIndex()),
4837
DbgInfo);
4838
}
4839
}
4840
const unsigned SS =
4841
UseVolatile ? Info.VolatileStorageSize : Info.StorageSize;
4842
// Get the access type.
4843
llvm::Type *FieldIntTy = llvm::Type::getIntNTy(getLLVMContext(), SS);
4844
Addr = Addr.withElementType(FieldIntTy);
4845
if (UseVolatile) {
4846
const unsigned VolatileOffset = Info.VolatileStorageOffset.getQuantity();
4847
if (VolatileOffset)
4848
Addr = Builder.CreateConstInBoundsGEP(Addr, VolatileOffset);
4849
}
4850
4851
QualType fieldType =
4852
field->getType().withCVRQualifiers(base.getVRQualifiers());
4853
// TODO: Support TBAA for bit fields.
4854
LValueBaseInfo FieldBaseInfo(BaseInfo.getAlignmentSource());
4855
return LValue::MakeBitfield(Addr, Info, fieldType, FieldBaseInfo,
4856
TBAAAccessInfo());
4857
}
4858
4859
// Fields of may-alias structures are may-alias themselves.
4860
// FIXME: this should get propagated down through anonymous structs
4861
// and unions.
4862
QualType FieldType = field->getType();
4863
const RecordDecl *rec = field->getParent();
4864
AlignmentSource BaseAlignSource = BaseInfo.getAlignmentSource();
4865
LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(BaseAlignSource));
4866
TBAAAccessInfo FieldTBAAInfo;
4867
if (base.getTBAAInfo().isMayAlias() ||
4868
rec->hasAttr<MayAliasAttr>() || FieldType->isVectorType()) {
4869
FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo();
4870
} else if (rec->isUnion()) {
4871
// TODO: Support TBAA for unions.
4872
FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo();
4873
} else {
4874
// If no base type been assigned for the base access, then try to generate
4875
// one for this base lvalue.
4876
FieldTBAAInfo = base.getTBAAInfo();
4877
if (!FieldTBAAInfo.BaseType) {
4878
FieldTBAAInfo.BaseType = CGM.getTBAABaseTypeInfo(base.getType());
4879
assert(!FieldTBAAInfo.Offset &&
4880
"Nonzero offset for an access with no base type!");
4881
}
4882
4883
// Adjust offset to be relative to the base type.
4884
const ASTRecordLayout &Layout =
4885
getContext().getASTRecordLayout(field->getParent());
4886
unsigned CharWidth = getContext().getCharWidth();
4887
if (FieldTBAAInfo.BaseType)
4888
FieldTBAAInfo.Offset +=
4889
Layout.getFieldOffset(field->getFieldIndex()) / CharWidth;
4890
4891
// Update the final access type and size.
4892
FieldTBAAInfo.AccessType = CGM.getTBAATypeInfo(FieldType);
4893
FieldTBAAInfo.Size =
4894
getContext().getTypeSizeInChars(FieldType).getQuantity();
4895
}
4896
4897
Address addr = base.getAddress();
4898
if (hasBPFPreserveStaticOffset(rec))
4899
addr = wrapWithBPFPreserveStaticOffset(*this, addr);
4900
if (auto *ClassDef = dyn_cast<CXXRecordDecl>(rec)) {
4901
if (CGM.getCodeGenOpts().StrictVTablePointers &&
4902
ClassDef->isDynamicClass()) {
4903
// Getting to any field of dynamic object requires stripping dynamic
4904
// information provided by invariant.group. This is because accessing
4905
// fields may leak the real address of dynamic object, which could result
4906
// in miscompilation when leaked pointer would be compared.
4907
auto *stripped =
4908
Builder.CreateStripInvariantGroup(addr.emitRawPointer(*this));
4909
addr = Address(stripped, addr.getElementType(), addr.getAlignment());
4910
}
4911
}
4912
4913
unsigned RecordCVR = base.getVRQualifiers();
4914
if (rec->isUnion()) {
4915
// For unions, there is no pointer adjustment.
4916
if (CGM.getCodeGenOpts().StrictVTablePointers &&
4917
hasAnyVptr(FieldType, getContext()))
4918
// Because unions can easily skip invariant.barriers, we need to add
4919
// a barrier every time CXXRecord field with vptr is referenced.
4920
addr = Builder.CreateLaunderInvariantGroup(addr);
4921
4922
if (IsInPreservedAIRegion ||
4923
(getDebugInfo() && rec->hasAttr<BPFPreserveAccessIndexAttr>())) {
4924
// Remember the original union field index
4925
llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateStandaloneType(base.getType(),
4926
rec->getLocation());
4927
addr =
4928
Address(Builder.CreatePreserveUnionAccessIndex(
4929
addr.emitRawPointer(*this),
4930
getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo),
4931
addr.getElementType(), addr.getAlignment());
4932
}
4933
4934
if (FieldType->isReferenceType())
4935
addr = addr.withElementType(CGM.getTypes().ConvertTypeForMem(FieldType));
4936
} else {
4937
if (!IsInPreservedAIRegion &&
4938
(!getDebugInfo() || !rec->hasAttr<BPFPreserveAccessIndexAttr>()))
4939
// For structs, we GEP to the field that the record layout suggests.
4940
addr = emitAddrOfFieldStorage(*this, addr, field);
4941
else
4942
// Remember the original struct field index
4943
addr = emitPreserveStructAccess(*this, base, addr, field);
4944
}
4945
4946
// If this is a reference field, load the reference right now.
4947
if (FieldType->isReferenceType()) {
4948
LValue RefLVal =
4949
MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo);
4950
if (RecordCVR & Qualifiers::Volatile)
4951
RefLVal.getQuals().addVolatile();
4952
addr = EmitLoadOfReference(RefLVal, &FieldBaseInfo, &FieldTBAAInfo);
4953
4954
// Qualifiers on the struct don't apply to the referencee.
4955
RecordCVR = 0;
4956
FieldType = FieldType->getPointeeType();
4957
}
4958
4959
// Make sure that the address is pointing to the right type. This is critical
4960
// for both unions and structs.
4961
addr = addr.withElementType(CGM.getTypes().ConvertTypeForMem(FieldType));
4962
4963
if (field->hasAttr<AnnotateAttr>())
4964
addr = EmitFieldAnnotations(field, addr);
4965
4966
LValue LV = MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo);
4967
LV.getQuals().addCVRQualifiers(RecordCVR);
4968
4969
// __weak attribute on a field is ignored.
4970
if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
4971
LV.getQuals().removeObjCGCAttr();
4972
4973
return LV;
4974
}
4975
4976
LValue
4977
CodeGenFunction::EmitLValueForFieldInitialization(LValue Base,
4978
const FieldDecl *Field) {
4979
QualType FieldType = Field->getType();
4980
4981
if (!FieldType->isReferenceType())
4982
return EmitLValueForField(Base, Field);
4983
4984
Address V = emitAddrOfFieldStorage(*this, Base.getAddress(), Field);
4985
4986
// Make sure that the address is pointing to the right type.
4987
llvm::Type *llvmType = ConvertTypeForMem(FieldType);
4988
V = V.withElementType(llvmType);
4989
4990
// TODO: Generate TBAA information that describes this access as a structure
4991
// member access and not just an access to an object of the field's type. This
4992
// should be similar to what we do in EmitLValueForField().
4993
LValueBaseInfo BaseInfo = Base.getBaseInfo();
4994
AlignmentSource FieldAlignSource = BaseInfo.getAlignmentSource();
4995
LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(FieldAlignSource));
4996
return MakeAddrLValue(V, FieldType, FieldBaseInfo,
4997
CGM.getTBAAInfoForSubobject(Base, FieldType));
4998
}
4999
5000
LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
5001
if (E->isFileScope()) {
5002
ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E);
5003
return MakeAddrLValue(GlobalPtr, E->getType(), AlignmentSource::Decl);
5004
}
5005
if (E->getType()->isVariablyModifiedType())
5006
// make sure to emit the VLA size.
5007
EmitVariablyModifiedType(E->getType());
5008
5009
Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
5010
const Expr *InitExpr = E->getInitializer();
5011
LValue Result = MakeAddrLValue(DeclPtr, E->getType(), AlignmentSource::Decl);
5012
5013
EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(),
5014
/*Init*/ true);
5015
5016
// Block-scope compound literals are destroyed at the end of the enclosing
5017
// scope in C.
5018
if (!getLangOpts().CPlusPlus)
5019
if (QualType::DestructionKind DtorKind = E->getType().isDestructedType())
5020
pushLifetimeExtendedDestroy(getCleanupKind(DtorKind), DeclPtr,
5021
E->getType(), getDestroyer(DtorKind),
5022
DtorKind & EHCleanup);
5023
5024
return Result;
5025
}
5026
5027
LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) {
5028
if (!E->isGLValue())
5029
// Initializing an aggregate temporary in C++11: T{...}.
5030
return EmitAggExprToLValue(E);
5031
5032
// An lvalue initializer list must be initializing a reference.
5033
assert(E->isTransparent() && "non-transparent glvalue init list");
5034
return EmitLValue(E->getInit(0));
5035
}
5036
5037
/// Emit the operand of a glvalue conditional operator. This is either a glvalue
5038
/// or a (possibly-parenthesized) throw-expression. If this is a throw, no
5039
/// LValue is returned and the current block has been terminated.
5040
static std::optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF,
5041
const Expr *Operand) {
5042
if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) {
5043
CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false);
5044
return std::nullopt;
5045
}
5046
5047
return CGF.EmitLValue(Operand);
5048
}
5049
5050
namespace {
5051
// Handle the case where the condition is a constant evaluatable simple integer,
5052
// which means we don't have to separately handle the true/false blocks.
5053
std::optional<LValue> HandleConditionalOperatorLValueSimpleCase(
5054
CodeGenFunction &CGF, const AbstractConditionalOperator *E) {
5055
const Expr *condExpr = E->getCond();
5056
bool CondExprBool;
5057
if (CGF.ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
5058
const Expr *Live = E->getTrueExpr(), *Dead = E->getFalseExpr();
5059
if (!CondExprBool)
5060
std::swap(Live, Dead);
5061
5062
if (!CGF.ContainsLabel(Dead)) {
5063
// If the true case is live, we need to track its region.
5064
if (CondExprBool)
5065
CGF.incrementProfileCounter(E);
5066
// If a throw expression we emit it and return an undefined lvalue
5067
// because it can't be used.
5068
if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Live->IgnoreParens())) {
5069
CGF.EmitCXXThrowExpr(ThrowExpr);
5070
llvm::Type *ElemTy = CGF.ConvertType(Dead->getType());
5071
llvm::Type *Ty = CGF.UnqualPtrTy;
5072
return CGF.MakeAddrLValue(
5073
Address(llvm::UndefValue::get(Ty), ElemTy, CharUnits::One()),
5074
Dead->getType());
5075
}
5076
return CGF.EmitLValue(Live);
5077
}
5078
}
5079
return std::nullopt;
5080
}
5081
struct ConditionalInfo {
5082
llvm::BasicBlock *lhsBlock, *rhsBlock;
5083
std::optional<LValue> LHS, RHS;
5084
};
5085
5086
// Create and generate the 3 blocks for a conditional operator.
5087
// Leaves the 'current block' in the continuation basic block.
5088
template<typename FuncTy>
5089
ConditionalInfo EmitConditionalBlocks(CodeGenFunction &CGF,
5090
const AbstractConditionalOperator *E,
5091
const FuncTy &BranchGenFunc) {
5092
ConditionalInfo Info{CGF.createBasicBlock("cond.true"),
5093
CGF.createBasicBlock("cond.false"), std::nullopt,
5094
std::nullopt};
5095
llvm::BasicBlock *endBlock = CGF.createBasicBlock("cond.end");
5096
5097
CodeGenFunction::ConditionalEvaluation eval(CGF);
5098
CGF.EmitBranchOnBoolExpr(E->getCond(), Info.lhsBlock, Info.rhsBlock,
5099
CGF.getProfileCount(E));
5100
5101
// Any temporaries created here are conditional.
5102
CGF.EmitBlock(Info.lhsBlock);
5103
CGF.incrementProfileCounter(E);
5104
eval.begin(CGF);
5105
Info.LHS = BranchGenFunc(CGF, E->getTrueExpr());
5106
eval.end(CGF);
5107
Info.lhsBlock = CGF.Builder.GetInsertBlock();
5108
5109
if (Info.LHS)
5110
CGF.Builder.CreateBr(endBlock);
5111
5112
// Any temporaries created here are conditional.
5113
CGF.EmitBlock(Info.rhsBlock);
5114
eval.begin(CGF);
5115
Info.RHS = BranchGenFunc(CGF, E->getFalseExpr());
5116
eval.end(CGF);
5117
Info.rhsBlock = CGF.Builder.GetInsertBlock();
5118
CGF.EmitBlock(endBlock);
5119
5120
return Info;
5121
}
5122
} // namespace
5123
5124
void CodeGenFunction::EmitIgnoredConditionalOperator(
5125
const AbstractConditionalOperator *E) {
5126
if (!E->isGLValue()) {
5127
// ?: here should be an aggregate.
5128
assert(hasAggregateEvaluationKind(E->getType()) &&
5129
"Unexpected conditional operator!");
5130
return (void)EmitAggExprToLValue(E);
5131
}
5132
5133
OpaqueValueMapping binding(*this, E);
5134
if (HandleConditionalOperatorLValueSimpleCase(*this, E))
5135
return;
5136
5137
EmitConditionalBlocks(*this, E, [](CodeGenFunction &CGF, const Expr *E) {
5138
CGF.EmitIgnoredExpr(E);
5139
return LValue{};
5140
});
5141
}
5142
LValue CodeGenFunction::EmitConditionalOperatorLValue(
5143
const AbstractConditionalOperator *expr) {
5144
if (!expr->isGLValue()) {
5145
// ?: here should be an aggregate.
5146
assert(hasAggregateEvaluationKind(expr->getType()) &&
5147
"Unexpected conditional operator!");
5148
return EmitAggExprToLValue(expr);
5149
}
5150
5151
OpaqueValueMapping binding(*this, expr);
5152
if (std::optional<LValue> Res =
5153
HandleConditionalOperatorLValueSimpleCase(*this, expr))
5154
return *Res;
5155
5156
ConditionalInfo Info = EmitConditionalBlocks(
5157
*this, expr, [](CodeGenFunction &CGF, const Expr *E) {
5158
return EmitLValueOrThrowExpression(CGF, E);
5159
});
5160
5161
if ((Info.LHS && !Info.LHS->isSimple()) ||
5162
(Info.RHS && !Info.RHS->isSimple()))
5163
return EmitUnsupportedLValue(expr, "conditional operator");
5164
5165
if (Info.LHS && Info.RHS) {
5166
Address lhsAddr = Info.LHS->getAddress();
5167
Address rhsAddr = Info.RHS->getAddress();
5168
Address result = mergeAddressesInConditionalExpr(
5169
lhsAddr, rhsAddr, Info.lhsBlock, Info.rhsBlock,
5170
Builder.GetInsertBlock(), expr->getType());
5171
AlignmentSource alignSource =
5172
std::max(Info.LHS->getBaseInfo().getAlignmentSource(),
5173
Info.RHS->getBaseInfo().getAlignmentSource());
5174
TBAAAccessInfo TBAAInfo = CGM.mergeTBAAInfoForConditionalOperator(
5175
Info.LHS->getTBAAInfo(), Info.RHS->getTBAAInfo());
5176
return MakeAddrLValue(result, expr->getType(), LValueBaseInfo(alignSource),
5177
TBAAInfo);
5178
} else {
5179
assert((Info.LHS || Info.RHS) &&
5180
"both operands of glvalue conditional are throw-expressions?");
5181
return Info.LHS ? *Info.LHS : *Info.RHS;
5182
}
5183
}
5184
5185
/// EmitCastLValue - Casts are never lvalues unless that cast is to a reference
5186
/// type. If the cast is to a reference, we can have the usual lvalue result,
5187
/// otherwise if a cast is needed by the code generator in an lvalue context,
5188
/// then it must mean that we need the address of an aggregate in order to
5189
/// access one of its members. This can happen for all the reasons that casts
5190
/// are permitted with aggregate result, including noop aggregate casts, and
5191
/// cast from scalar to union.
5192
LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
5193
switch (E->getCastKind()) {
5194
case CK_ToVoid:
5195
case CK_BitCast:
5196
case CK_LValueToRValueBitCast:
5197
case CK_ArrayToPointerDecay:
5198
case CK_FunctionToPointerDecay:
5199
case CK_NullToMemberPointer:
5200
case CK_NullToPointer:
5201
case CK_IntegralToPointer:
5202
case CK_PointerToIntegral:
5203
case CK_PointerToBoolean:
5204
case CK_IntegralCast:
5205
case CK_BooleanToSignedIntegral:
5206
case CK_IntegralToBoolean:
5207
case CK_IntegralToFloating:
5208
case CK_FloatingToIntegral:
5209
case CK_FloatingToBoolean:
5210
case CK_FloatingCast:
5211
case CK_FloatingRealToComplex:
5212
case CK_FloatingComplexToReal:
5213
case CK_FloatingComplexToBoolean:
5214
case CK_FloatingComplexCast:
5215
case CK_FloatingComplexToIntegralComplex:
5216
case CK_IntegralRealToComplex:
5217
case CK_IntegralComplexToReal:
5218
case CK_IntegralComplexToBoolean:
5219
case CK_IntegralComplexCast:
5220
case CK_IntegralComplexToFloatingComplex:
5221
case CK_DerivedToBaseMemberPointer:
5222
case CK_BaseToDerivedMemberPointer:
5223
case CK_MemberPointerToBoolean:
5224
case CK_ReinterpretMemberPointer:
5225
case CK_AnyPointerToBlockPointerCast:
5226
case CK_ARCProduceObject:
5227
case CK_ARCConsumeObject:
5228
case CK_ARCReclaimReturnedObject:
5229
case CK_ARCExtendBlockObject:
5230
case CK_CopyAndAutoreleaseBlockObject:
5231
case CK_IntToOCLSampler:
5232
case CK_FloatingToFixedPoint:
5233
case CK_FixedPointToFloating:
5234
case CK_FixedPointCast:
5235
case CK_FixedPointToBoolean:
5236
case CK_FixedPointToIntegral:
5237
case CK_IntegralToFixedPoint:
5238
case CK_MatrixCast:
5239
case CK_HLSLVectorTruncation:
5240
case CK_HLSLArrayRValue:
5241
return EmitUnsupportedLValue(E, "unexpected cast lvalue");
5242
5243
case CK_Dependent:
5244
llvm_unreachable("dependent cast kind in IR gen!");
5245
5246
case CK_BuiltinFnToFnPtr:
5247
llvm_unreachable("builtin functions are handled elsewhere");
5248
5249
// These are never l-values; just use the aggregate emission code.
5250
case CK_NonAtomicToAtomic:
5251
case CK_AtomicToNonAtomic:
5252
return EmitAggExprToLValue(E);
5253
5254
case CK_Dynamic: {
5255
LValue LV = EmitLValue(E->getSubExpr());
5256
Address V = LV.getAddress();
5257
const auto *DCE = cast<CXXDynamicCastExpr>(E);
5258
return MakeNaturalAlignRawAddrLValue(EmitDynamicCast(V, DCE), E->getType());
5259
}
5260
5261
case CK_ConstructorConversion:
5262
case CK_UserDefinedConversion:
5263
case CK_CPointerToObjCPointerCast:
5264
case CK_BlockPointerToObjCPointerCast:
5265
case CK_LValueToRValue:
5266
return EmitLValue(E->getSubExpr());
5267
5268
case CK_NoOp: {
5269
// CK_NoOp can model a qualification conversion, which can remove an array
5270
// bound and change the IR type.
5271
// FIXME: Once pointee types are removed from IR, remove this.
5272
LValue LV = EmitLValue(E->getSubExpr());
5273
// Propagate the volatile qualifer to LValue, if exist in E.
5274
if (E->changesVolatileQualification())
5275
LV.getQuals() = E->getType().getQualifiers();
5276
if (LV.isSimple()) {
5277
Address V = LV.getAddress();
5278
if (V.isValid()) {
5279
llvm::Type *T = ConvertTypeForMem(E->getType());
5280
if (V.getElementType() != T)
5281
LV.setAddress(V.withElementType(T));
5282
}
5283
}
5284
return LV;
5285
}
5286
5287
case CK_UncheckedDerivedToBase:
5288
case CK_DerivedToBase: {
5289
const auto *DerivedClassTy =
5290
E->getSubExpr()->getType()->castAs<RecordType>();
5291
auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
5292
5293
LValue LV = EmitLValue(E->getSubExpr());
5294
Address This = LV.getAddress();
5295
5296
// Perform the derived-to-base conversion
5297
Address Base = GetAddressOfBaseClass(
5298
This, DerivedClassDecl, E->path_begin(), E->path_end(),
5299
/*NullCheckValue=*/false, E->getExprLoc());
5300
5301
// TODO: Support accesses to members of base classes in TBAA. For now, we
5302
// conservatively pretend that the complete object is of the base class
5303
// type.
5304
return MakeAddrLValue(Base, E->getType(), LV.getBaseInfo(),
5305
CGM.getTBAAInfoForSubobject(LV, E->getType()));
5306
}
5307
case CK_ToUnion:
5308
return EmitAggExprToLValue(E);
5309
case CK_BaseToDerived: {
5310
const auto *DerivedClassTy = E->getType()->castAs<RecordType>();
5311
auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
5312
5313
LValue LV = EmitLValue(E->getSubExpr());
5314
5315
// Perform the base-to-derived conversion
5316
Address Derived = GetAddressOfDerivedClass(
5317
LV.getAddress(), DerivedClassDecl, E->path_begin(), E->path_end(),
5318
/*NullCheckValue=*/false);
5319
5320
// C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is
5321
// performed and the object is not of the derived type.
5322
if (sanitizePerformTypeCheck())
5323
EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(), Derived,
5324
E->getType());
5325
5326
if (SanOpts.has(SanitizerKind::CFIDerivedCast))
5327
EmitVTablePtrCheckForCast(E->getType(), Derived,
5328
/*MayBeNull=*/false, CFITCK_DerivedCast,
5329
E->getBeginLoc());
5330
5331
return MakeAddrLValue(Derived, E->getType(), LV.getBaseInfo(),
5332
CGM.getTBAAInfoForSubobject(LV, E->getType()));
5333
}
5334
case CK_LValueBitCast: {
5335
// This must be a reinterpret_cast (or c-style equivalent).
5336
const auto *CE = cast<ExplicitCastExpr>(E);
5337
5338
CGM.EmitExplicitCastExprType(CE, this);
5339
LValue LV = EmitLValue(E->getSubExpr());
5340
Address V = LV.getAddress().withElementType(
5341
ConvertTypeForMem(CE->getTypeAsWritten()->getPointeeType()));
5342
5343
if (SanOpts.has(SanitizerKind::CFIUnrelatedCast))
5344
EmitVTablePtrCheckForCast(E->getType(), V,
5345
/*MayBeNull=*/false, CFITCK_UnrelatedCast,
5346
E->getBeginLoc());
5347
5348
return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(),
5349
CGM.getTBAAInfoForSubobject(LV, E->getType()));
5350
}
5351
case CK_AddressSpaceConversion: {
5352
LValue LV = EmitLValue(E->getSubExpr());
5353
QualType DestTy = getContext().getPointerType(E->getType());
5354
llvm::Value *V = getTargetHooks().performAddrSpaceCast(
5355
*this, LV.getPointer(*this),
5356
E->getSubExpr()->getType().getAddressSpace(),
5357
E->getType().getAddressSpace(), ConvertType(DestTy));
5358
return MakeAddrLValue(Address(V, ConvertTypeForMem(E->getType()),
5359
LV.getAddress().getAlignment()),
5360
E->getType(), LV.getBaseInfo(), LV.getTBAAInfo());
5361
}
5362
case CK_ObjCObjectLValueCast: {
5363
LValue LV = EmitLValue(E->getSubExpr());
5364
Address V = LV.getAddress().withElementType(ConvertType(E->getType()));
5365
return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(),
5366
CGM.getTBAAInfoForSubobject(LV, E->getType()));
5367
}
5368
case CK_ZeroToOCLOpaqueType:
5369
llvm_unreachable("NULL to OpenCL opaque type lvalue cast is not valid");
5370
5371
case CK_VectorSplat: {
5372
// LValue results of vector splats are only supported in HLSL.
5373
if (!getLangOpts().HLSL)
5374
return EmitUnsupportedLValue(E, "unexpected cast lvalue");
5375
return EmitLValue(E->getSubExpr());
5376
}
5377
}
5378
5379
llvm_unreachable("Unhandled lvalue cast kind?");
5380
}
5381
5382
LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
5383
assert(OpaqueValueMappingData::shouldBindAsLValue(e));
5384
return getOrCreateOpaqueLValueMapping(e);
5385
}
5386
5387
LValue
5388
CodeGenFunction::getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e) {
5389
assert(OpaqueValueMapping::shouldBindAsLValue(e));
5390
5391
llvm::DenseMap<const OpaqueValueExpr*,LValue>::iterator
5392
it = OpaqueLValues.find(e);
5393
5394
if (it != OpaqueLValues.end())
5395
return it->second;
5396
5397
assert(e->isUnique() && "LValue for a nonunique OVE hasn't been emitted");
5398
return EmitLValue(e->getSourceExpr());
5399
}
5400
5401
RValue
5402
CodeGenFunction::getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e) {
5403
assert(!OpaqueValueMapping::shouldBindAsLValue(e));
5404
5405
llvm::DenseMap<const OpaqueValueExpr*,RValue>::iterator
5406
it = OpaqueRValues.find(e);
5407
5408
if (it != OpaqueRValues.end())
5409
return it->second;
5410
5411
assert(e->isUnique() && "RValue for a nonunique OVE hasn't been emitted");
5412
return EmitAnyExpr(e->getSourceExpr());
5413
}
5414
5415
RValue CodeGenFunction::EmitRValueForField(LValue LV,
5416
const FieldDecl *FD,
5417
SourceLocation Loc) {
5418
QualType FT = FD->getType();
5419
LValue FieldLV = EmitLValueForField(LV, FD);
5420
switch (getEvaluationKind(FT)) {
5421
case TEK_Complex:
5422
return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc));
5423
case TEK_Aggregate:
5424
return FieldLV.asAggregateRValue();
5425
case TEK_Scalar:
5426
// This routine is used to load fields one-by-one to perform a copy, so
5427
// don't load reference fields.
5428
if (FD->getType()->isReferenceType())
5429
return RValue::get(FieldLV.getPointer(*this));
5430
// Call EmitLoadOfScalar except when the lvalue is a bitfield to emit a
5431
// primitive load.
5432
if (FieldLV.isBitField())
5433
return EmitLoadOfLValue(FieldLV, Loc);
5434
return RValue::get(EmitLoadOfScalar(FieldLV, Loc));
5435
}
5436
llvm_unreachable("bad evaluation kind");
5437
}
5438
5439
//===--------------------------------------------------------------------===//
5440
// Expression Emission
5441
//===--------------------------------------------------------------------===//
5442
5443
RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
5444
ReturnValueSlot ReturnValue) {
5445
// Builtins never have block type.
5446
if (E->getCallee()->getType()->isBlockPointerType())
5447
return EmitBlockCallExpr(E, ReturnValue);
5448
5449
if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E))
5450
return EmitCXXMemberCallExpr(CE, ReturnValue);
5451
5452
if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E))
5453
return EmitCUDAKernelCallExpr(CE, ReturnValue);
5454
5455
// A CXXOperatorCallExpr is created even for explicit object methods, but
5456
// these should be treated like static function call.
5457
if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E))
5458
if (const auto *MD =
5459
dyn_cast_if_present<CXXMethodDecl>(CE->getCalleeDecl());
5460
MD && MD->isImplicitObjectMemberFunction())
5461
return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
5462
5463
CGCallee callee = EmitCallee(E->getCallee());
5464
5465
if (callee.isBuiltin()) {
5466
return EmitBuiltinExpr(callee.getBuiltinDecl(), callee.getBuiltinID(),
5467
E, ReturnValue);
5468
}
5469
5470
if (callee.isPseudoDestructor()) {
5471
return EmitCXXPseudoDestructorExpr(callee.getPseudoDestructorExpr());
5472
}
5473
5474
return EmitCall(E->getCallee()->getType(), callee, E, ReturnValue);
5475
}
5476
5477
/// Emit a CallExpr without considering whether it might be a subclass.
5478
RValue CodeGenFunction::EmitSimpleCallExpr(const CallExpr *E,
5479
ReturnValueSlot ReturnValue) {
5480
CGCallee Callee = EmitCallee(E->getCallee());
5481
return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue);
5482
}
5483
5484
// Detect the unusual situation where an inline version is shadowed by a
5485
// non-inline version. In that case we should pick the external one
5486
// everywhere. That's GCC behavior too.
5487
static bool OnlyHasInlineBuiltinDeclaration(const FunctionDecl *FD) {
5488
for (const FunctionDecl *PD = FD; PD; PD = PD->getPreviousDecl())
5489
if (!PD->isInlineBuiltinDeclaration())
5490
return false;
5491
return true;
5492
}
5493
5494
static CGCallee EmitDirectCallee(CodeGenFunction &CGF, GlobalDecl GD) {
5495
const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
5496
5497
if (auto builtinID = FD->getBuiltinID()) {
5498
std::string NoBuiltinFD = ("no-builtin-" + FD->getName()).str();
5499
std::string NoBuiltins = "no-builtins";
5500
5501
StringRef Ident = CGF.CGM.getMangledName(GD);
5502
std::string FDInlineName = (Ident + ".inline").str();
5503
5504
bool IsPredefinedLibFunction =
5505
CGF.getContext().BuiltinInfo.isPredefinedLibFunction(builtinID);
5506
bool HasAttributeNoBuiltin =
5507
CGF.CurFn->getAttributes().hasFnAttr(NoBuiltinFD) ||
5508
CGF.CurFn->getAttributes().hasFnAttr(NoBuiltins);
5509
5510
// When directing calling an inline builtin, call it through it's mangled
5511
// name to make it clear it's not the actual builtin.
5512
if (CGF.CurFn->getName() != FDInlineName &&
5513
OnlyHasInlineBuiltinDeclaration(FD)) {
5514
llvm::Constant *CalleePtr = CGF.CGM.getRawFunctionPointer(GD);
5515
llvm::Function *Fn = llvm::cast<llvm::Function>(CalleePtr);
5516
llvm::Module *M = Fn->getParent();
5517
llvm::Function *Clone = M->getFunction(FDInlineName);
5518
if (!Clone) {
5519
Clone = llvm::Function::Create(Fn->getFunctionType(),
5520
llvm::GlobalValue::InternalLinkage,
5521
Fn->getAddressSpace(), FDInlineName, M);
5522
Clone->addFnAttr(llvm::Attribute::AlwaysInline);
5523
}
5524
return CGCallee::forDirect(Clone, GD);
5525
}
5526
5527
// Replaceable builtins provide their own implementation of a builtin. If we
5528
// are in an inline builtin implementation, avoid trivial infinite
5529
// recursion. Honor __attribute__((no_builtin("foo"))) or
5530
// __attribute__((no_builtin)) on the current function unless foo is
5531
// not a predefined library function which means we must generate the
5532
// builtin no matter what.
5533
else if (!IsPredefinedLibFunction || !HasAttributeNoBuiltin)
5534
return CGCallee::forBuiltin(builtinID, FD);
5535
}
5536
5537
llvm::Constant *CalleePtr = CGF.CGM.getRawFunctionPointer(GD);
5538
if (CGF.CGM.getLangOpts().CUDA && !CGF.CGM.getLangOpts().CUDAIsDevice &&
5539
FD->hasAttr<CUDAGlobalAttr>())
5540
CalleePtr = CGF.CGM.getCUDARuntime().getKernelStub(
5541
cast<llvm::GlobalValue>(CalleePtr->stripPointerCasts()));
5542
5543
return CGCallee::forDirect(CalleePtr, GD);
5544
}
5545
5546
CGCallee CodeGenFunction::EmitCallee(const Expr *E) {
5547
E = E->IgnoreParens();
5548
5549
// Look through function-to-pointer decay.
5550
if (auto ICE = dyn_cast<ImplicitCastExpr>(E)) {
5551
if (ICE->getCastKind() == CK_FunctionToPointerDecay ||
5552
ICE->getCastKind() == CK_BuiltinFnToFnPtr) {
5553
return EmitCallee(ICE->getSubExpr());
5554
}
5555
5556
// Resolve direct calls.
5557
} else if (auto DRE = dyn_cast<DeclRefExpr>(E)) {
5558
if (auto FD = dyn_cast<FunctionDecl>(DRE->getDecl())) {
5559
return EmitDirectCallee(*this, FD);
5560
}
5561
} else if (auto ME = dyn_cast<MemberExpr>(E)) {
5562
if (auto FD = dyn_cast<FunctionDecl>(ME->getMemberDecl())) {
5563
EmitIgnoredExpr(ME->getBase());
5564
return EmitDirectCallee(*this, FD);
5565
}
5566
5567
// Look through template substitutions.
5568
} else if (auto NTTP = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
5569
return EmitCallee(NTTP->getReplacement());
5570
5571
// Treat pseudo-destructor calls differently.
5572
} else if (auto PDE = dyn_cast<CXXPseudoDestructorExpr>(E)) {
5573
return CGCallee::forPseudoDestructor(PDE);
5574
}
5575
5576
// Otherwise, we have an indirect reference.
5577
llvm::Value *calleePtr;
5578
QualType functionType;
5579
if (auto ptrType = E->getType()->getAs<PointerType>()) {
5580
calleePtr = EmitScalarExpr(E);
5581
functionType = ptrType->getPointeeType();
5582
} else {
5583
functionType = E->getType();
5584
calleePtr = EmitLValue(E, KnownNonNull).getPointer(*this);
5585
}
5586
assert(functionType->isFunctionType());
5587
5588
GlobalDecl GD;
5589
if (const auto *VD =
5590
dyn_cast_or_null<VarDecl>(E->getReferencedDeclOfCallee()))
5591
GD = GlobalDecl(VD);
5592
5593
CGCalleeInfo calleeInfo(functionType->getAs<FunctionProtoType>(), GD);
5594
CGPointerAuthInfo pointerAuth = CGM.getFunctionPointerAuthInfo(functionType);
5595
CGCallee callee(calleeInfo, calleePtr, pointerAuth);
5596
return callee;
5597
}
5598
5599
LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
5600
// Comma expressions just emit their LHS then their RHS as an l-value.
5601
if (E->getOpcode() == BO_Comma) {
5602
EmitIgnoredExpr(E->getLHS());
5603
EnsureInsertPoint();
5604
return EmitLValue(E->getRHS());
5605
}
5606
5607
if (E->getOpcode() == BO_PtrMemD ||
5608
E->getOpcode() == BO_PtrMemI)
5609
return EmitPointerToDataMemberBinaryExpr(E);
5610
5611
assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
5612
5613
// Note that in all of these cases, __block variables need the RHS
5614
// evaluated first just in case the variable gets moved by the RHS.
5615
5616
switch (getEvaluationKind(E->getType())) {
5617
case TEK_Scalar: {
5618
switch (E->getLHS()->getType().getObjCLifetime()) {
5619
case Qualifiers::OCL_Strong:
5620
return EmitARCStoreStrong(E, /*ignored*/ false).first;
5621
5622
case Qualifiers::OCL_Autoreleasing:
5623
return EmitARCStoreAutoreleasing(E).first;
5624
5625
// No reason to do any of these differently.
5626
case Qualifiers::OCL_None:
5627
case Qualifiers::OCL_ExplicitNone:
5628
case Qualifiers::OCL_Weak:
5629
break;
5630
}
5631
5632
// TODO: Can we de-duplicate this code with the corresponding code in
5633
// CGExprScalar, similar to the way EmitCompoundAssignmentLValue works?
5634
RValue RV;
5635
llvm::Value *Previous = nullptr;
5636
QualType SrcType = E->getRHS()->getType();
5637
// Check if LHS is a bitfield, if RHS contains an implicit cast expression
5638
// we want to extract that value and potentially (if the bitfield sanitizer
5639
// is enabled) use it to check for an implicit conversion.
5640
if (E->getLHS()->refersToBitField()) {
5641
llvm::Value *RHS =
5642
EmitWithOriginalRHSBitfieldAssignment(E, &Previous, &SrcType);
5643
RV = RValue::get(RHS);
5644
} else
5645
RV = EmitAnyExpr(E->getRHS());
5646
5647
LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
5648
5649
if (RV.isScalar())
5650
EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc());
5651
5652
if (LV.isBitField()) {
5653
llvm::Value *Result = nullptr;
5654
// If bitfield sanitizers are enabled we want to use the result
5655
// to check whether a truncation or sign change has occurred.
5656
if (SanOpts.has(SanitizerKind::ImplicitBitfieldConversion))
5657
EmitStoreThroughBitfieldLValue(RV, LV, &Result);
5658
else
5659
EmitStoreThroughBitfieldLValue(RV, LV);
5660
5661
// If the expression contained an implicit conversion, make sure
5662
// to use the value before the scalar conversion.
5663
llvm::Value *Src = Previous ? Previous : RV.getScalarVal();
5664
QualType DstType = E->getLHS()->getType();
5665
EmitBitfieldConversionCheck(Src, SrcType, Result, DstType,
5666
LV.getBitFieldInfo(), E->getExprLoc());
5667
} else
5668
EmitStoreThroughLValue(RV, LV);
5669
5670
if (getLangOpts().OpenMP)
5671
CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this,
5672
E->getLHS());
5673
return LV;
5674
}
5675
5676
case TEK_Complex:
5677
return EmitComplexAssignmentLValue(E);
5678
5679
case TEK_Aggregate:
5680
return EmitAggExprToLValue(E);
5681
}
5682
llvm_unreachable("bad evaluation kind");
5683
}
5684
5685
LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
5686
RValue RV = EmitCallExpr(E);
5687
5688
if (!RV.isScalar())
5689
return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
5690
AlignmentSource::Decl);
5691
5692
assert(E->getCallReturnType(getContext())->isReferenceType() &&
5693
"Can't have a scalar return unless the return type is a "
5694
"reference type!");
5695
5696
return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
5697
}
5698
5699
LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
5700
// FIXME: This shouldn't require another copy.
5701
return EmitAggExprToLValue(E);
5702
}
5703
5704
LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
5705
assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
5706
&& "binding l-value to type which needs a temporary");
5707
AggValueSlot Slot = CreateAggTemp(E->getType());
5708
EmitCXXConstructExpr(E, Slot);
5709
return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
5710
}
5711
5712
LValue
5713
CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
5714
return MakeNaturalAlignRawAddrLValue(EmitCXXTypeidExpr(E), E->getType());
5715
}
5716
5717
Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) {
5718
return CGM.GetAddrOfMSGuidDecl(E->getGuidDecl())
5719
.withElementType(ConvertType(E->getType()));
5720
}
5721
5722
LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) {
5723
return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(),
5724
AlignmentSource::Decl);
5725
}
5726
5727
LValue
5728
CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
5729
AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
5730
Slot.setExternallyDestructed();
5731
EmitAggExpr(E->getSubExpr(), Slot);
5732
EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress());
5733
return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
5734
}
5735
5736
LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
5737
RValue RV = EmitObjCMessageExpr(E);
5738
5739
if (!RV.isScalar())
5740
return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
5741
AlignmentSource::Decl);
5742
5743
assert(E->getMethodDecl()->getReturnType()->isReferenceType() &&
5744
"Can't have a scalar return unless the return type is a "
5745
"reference type!");
5746
5747
return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
5748
}
5749
5750
LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
5751
Address V =
5752
CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector());
5753
return MakeAddrLValue(V, E->getType(), AlignmentSource::Decl);
5754
}
5755
5756
llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
5757
const ObjCIvarDecl *Ivar) {
5758
return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
5759
}
5760
5761
llvm::Value *
5762
CodeGenFunction::EmitIvarOffsetAsPointerDiff(const ObjCInterfaceDecl *Interface,
5763
const ObjCIvarDecl *Ivar) {
5764
llvm::Value *OffsetValue = EmitIvarOffset(Interface, Ivar);
5765
QualType PointerDiffType = getContext().getPointerDiffType();
5766
return Builder.CreateZExtOrTrunc(OffsetValue,
5767
getTypes().ConvertType(PointerDiffType));
5768
}
5769
5770
LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
5771
llvm::Value *BaseValue,
5772
const ObjCIvarDecl *Ivar,
5773
unsigned CVRQualifiers) {
5774
return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
5775
Ivar, CVRQualifiers);
5776
}
5777
5778
LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
5779
// FIXME: A lot of the code below could be shared with EmitMemberExpr.
5780
llvm::Value *BaseValue = nullptr;
5781
const Expr *BaseExpr = E->getBase();
5782
Qualifiers BaseQuals;
5783
QualType ObjectTy;
5784
if (E->isArrow()) {
5785
BaseValue = EmitScalarExpr(BaseExpr);
5786
ObjectTy = BaseExpr->getType()->getPointeeType();
5787
BaseQuals = ObjectTy.getQualifiers();
5788
} else {
5789
LValue BaseLV = EmitLValue(BaseExpr);
5790
BaseValue = BaseLV.getPointer(*this);
5791
ObjectTy = BaseExpr->getType();
5792
BaseQuals = ObjectTy.getQualifiers();
5793
}
5794
5795
LValue LV =
5796
EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
5797
BaseQuals.getCVRQualifiers());
5798
setObjCGCLValueClass(getContext(), E, LV);
5799
return LV;
5800
}
5801
5802
LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
5803
// Can only get l-value for message expression returning aggregate type
5804
RValue RV = EmitAnyExprToTemp(E);
5805
return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
5806
AlignmentSource::Decl);
5807
}
5808
5809
RValue CodeGenFunction::EmitCall(QualType CalleeType, const CGCallee &OrigCallee,
5810
const CallExpr *E, ReturnValueSlot ReturnValue,
5811
llvm::Value *Chain) {
5812
// Get the actual function type. The callee type will always be a pointer to
5813
// function type or a block pointer type.
5814
assert(CalleeType->isFunctionPointerType() &&
5815
"Call must have function pointer type!");
5816
5817
const Decl *TargetDecl =
5818
OrigCallee.getAbstractInfo().getCalleeDecl().getDecl();
5819
5820
assert((!isa_and_present<FunctionDecl>(TargetDecl) ||
5821
!cast<FunctionDecl>(TargetDecl)->isImmediateFunction()) &&
5822
"trying to emit a call to an immediate function");
5823
5824
CalleeType = getContext().getCanonicalType(CalleeType);
5825
5826
auto PointeeType = cast<PointerType>(CalleeType)->getPointeeType();
5827
5828
CGCallee Callee = OrigCallee;
5829
5830
if (SanOpts.has(SanitizerKind::Function) &&
5831
(!TargetDecl || !isa<FunctionDecl>(TargetDecl)) &&
5832
!isa<FunctionNoProtoType>(PointeeType)) {
5833
if (llvm::Constant *PrefixSig =
5834
CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
5835
SanitizerScope SanScope(this);
5836
auto *TypeHash = getUBSanFunctionTypeHash(PointeeType);
5837
5838
llvm::Type *PrefixSigType = PrefixSig->getType();
5839
llvm::StructType *PrefixStructTy = llvm::StructType::get(
5840
CGM.getLLVMContext(), {PrefixSigType, Int32Ty}, /*isPacked=*/true);
5841
5842
llvm::Value *CalleePtr = Callee.getFunctionPointer();
5843
if (CGM.getCodeGenOpts().PointerAuth.FunctionPointers) {
5844
// Use raw pointer since we are using the callee pointer as data here.
5845
Address Addr =
5846
Address(CalleePtr, CalleePtr->getType(),
5847
CharUnits::fromQuantity(
5848
CalleePtr->getPointerAlignment(CGM.getDataLayout())),
5849
Callee.getPointerAuthInfo(), nullptr);
5850
CalleePtr = Addr.emitRawPointer(*this);
5851
}
5852
5853
// On 32-bit Arm, the low bit of a function pointer indicates whether
5854
// it's using the Arm or Thumb instruction set. The actual first
5855
// instruction lives at the same address either way, so we must clear
5856
// that low bit before using the function address to find the prefix
5857
// structure.
5858
//
5859
// This applies to both Arm and Thumb target triples, because
5860
// either one could be used in an interworking context where it
5861
// might be passed function pointers of both types.
5862
llvm::Value *AlignedCalleePtr;
5863
if (CGM.getTriple().isARM() || CGM.getTriple().isThumb()) {
5864
llvm::Value *CalleeAddress =
5865
Builder.CreatePtrToInt(CalleePtr, IntPtrTy);
5866
llvm::Value *Mask = llvm::ConstantInt::get(IntPtrTy, ~1);
5867
llvm::Value *AlignedCalleeAddress =
5868
Builder.CreateAnd(CalleeAddress, Mask);
5869
AlignedCalleePtr =
5870
Builder.CreateIntToPtr(AlignedCalleeAddress, CalleePtr->getType());
5871
} else {
5872
AlignedCalleePtr = CalleePtr;
5873
}
5874
5875
llvm::Value *CalleePrefixStruct = AlignedCalleePtr;
5876
llvm::Value *CalleeSigPtr =
5877
Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, -1, 0);
5878
llvm::Value *CalleeSig =
5879
Builder.CreateAlignedLoad(PrefixSigType, CalleeSigPtr, getIntAlign());
5880
llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig);
5881
5882
llvm::BasicBlock *Cont = createBasicBlock("cont");
5883
llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck");
5884
Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont);
5885
5886
EmitBlock(TypeCheck);
5887
llvm::Value *CalleeTypeHash = Builder.CreateAlignedLoad(
5888
Int32Ty,
5889
Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, -1, 1),
5890
getPointerAlign());
5891
llvm::Value *CalleeTypeHashMatch =
5892
Builder.CreateICmpEQ(CalleeTypeHash, TypeHash);
5893
llvm::Constant *StaticData[] = {EmitCheckSourceLocation(E->getBeginLoc()),
5894
EmitCheckTypeDescriptor(CalleeType)};
5895
EmitCheck(std::make_pair(CalleeTypeHashMatch, SanitizerKind::Function),
5896
SanitizerHandler::FunctionTypeMismatch, StaticData,
5897
{CalleePtr});
5898
5899
Builder.CreateBr(Cont);
5900
EmitBlock(Cont);
5901
}
5902
}
5903
5904
const auto *FnType = cast<FunctionType>(PointeeType);
5905
5906
// If we are checking indirect calls and this call is indirect, check that the
5907
// function pointer is a member of the bit set for the function type.
5908
if (SanOpts.has(SanitizerKind::CFIICall) &&
5909
(!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
5910
SanitizerScope SanScope(this);
5911
EmitSanitizerStatReport(llvm::SanStat_CFI_ICall);
5912
5913
llvm::Metadata *MD;
5914
if (CGM.getCodeGenOpts().SanitizeCfiICallGeneralizePointers)
5915
MD = CGM.CreateMetadataIdentifierGeneralized(QualType(FnType, 0));
5916
else
5917
MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0));
5918
5919
llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD);
5920
5921
llvm::Value *CalleePtr = Callee.getFunctionPointer();
5922
llvm::Value *TypeTest = Builder.CreateCall(
5923
CGM.getIntrinsic(llvm::Intrinsic::type_test), {CalleePtr, TypeId});
5924
5925
auto CrossDsoTypeId = CGM.CreateCrossDsoCfiTypeId(MD);
5926
llvm::Constant *StaticData[] = {
5927
llvm::ConstantInt::get(Int8Ty, CFITCK_ICall),
5928
EmitCheckSourceLocation(E->getBeginLoc()),
5929
EmitCheckTypeDescriptor(QualType(FnType, 0)),
5930
};
5931
if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && CrossDsoTypeId) {
5932
EmitCfiSlowPathCheck(SanitizerKind::CFIICall, TypeTest, CrossDsoTypeId,
5933
CalleePtr, StaticData);
5934
} else {
5935
EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIICall),
5936
SanitizerHandler::CFICheckFail, StaticData,
5937
{CalleePtr, llvm::UndefValue::get(IntPtrTy)});
5938
}
5939
}
5940
5941
CallArgList Args;
5942
if (Chain)
5943
Args.add(RValue::get(Chain), CGM.getContext().VoidPtrTy);
5944
5945
// C++17 requires that we evaluate arguments to a call using assignment syntax
5946
// right-to-left, and that we evaluate arguments to certain other operators
5947
// left-to-right. Note that we allow this to override the order dictated by
5948
// the calling convention on the MS ABI, which means that parameter
5949
// destruction order is not necessarily reverse construction order.
5950
// FIXME: Revisit this based on C++ committee response to unimplementability.
5951
EvaluationOrder Order = EvaluationOrder::Default;
5952
bool StaticOperator = false;
5953
if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(E)) {
5954
if (OCE->isAssignmentOp())
5955
Order = EvaluationOrder::ForceRightToLeft;
5956
else {
5957
switch (OCE->getOperator()) {
5958
case OO_LessLess:
5959
case OO_GreaterGreater:
5960
case OO_AmpAmp:
5961
case OO_PipePipe:
5962
case OO_Comma:
5963
case OO_ArrowStar:
5964
Order = EvaluationOrder::ForceLeftToRight;
5965
break;
5966
default:
5967
break;
5968
}
5969
}
5970
5971
if (const auto *MD =
5972
dyn_cast_if_present<CXXMethodDecl>(OCE->getCalleeDecl());
5973
MD && MD->isStatic())
5974
StaticOperator = true;
5975
}
5976
5977
auto Arguments = E->arguments();
5978
if (StaticOperator) {
5979
// If we're calling a static operator, we need to emit the object argument
5980
// and ignore it.
5981
EmitIgnoredExpr(E->getArg(0));
5982
Arguments = drop_begin(Arguments, 1);
5983
}
5984
EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), Arguments,
5985
E->getDirectCallee(), /*ParamsToSkip=*/0, Order);
5986
5987
const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall(
5988
Args, FnType, /*ChainCall=*/Chain);
5989
5990
// C99 6.5.2.2p6:
5991
// If the expression that denotes the called function has a type
5992
// that does not include a prototype, [the default argument
5993
// promotions are performed]. If the number of arguments does not
5994
// equal the number of parameters, the behavior is undefined. If
5995
// the function is defined with a type that includes a prototype,
5996
// and either the prototype ends with an ellipsis (, ...) or the
5997
// types of the arguments after promotion are not compatible with
5998
// the types of the parameters, the behavior is undefined. If the
5999
// function is defined with a type that does not include a
6000
// prototype, and the types of the arguments after promotion are
6001
// not compatible with those of the parameters after promotion,
6002
// the behavior is undefined [except in some trivial cases].
6003
// That is, in the general case, we should assume that a call
6004
// through an unprototyped function type works like a *non-variadic*
6005
// call. The way we make this work is to cast to the exact type
6006
// of the promoted arguments.
6007
//
6008
// Chain calls use this same code path to add the invisible chain parameter
6009
// to the function type.
6010
if (isa<FunctionNoProtoType>(FnType) || Chain) {
6011
llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo);
6012
int AS = Callee.getFunctionPointer()->getType()->getPointerAddressSpace();
6013
CalleeTy = CalleeTy->getPointerTo(AS);
6014
6015
llvm::Value *CalleePtr = Callee.getFunctionPointer();
6016
CalleePtr = Builder.CreateBitCast(CalleePtr, CalleeTy, "callee.knr.cast");
6017
Callee.setFunctionPointer(CalleePtr);
6018
}
6019
6020
// HIP function pointer contains kernel handle when it is used in triple
6021
// chevron. The kernel stub needs to be loaded from kernel handle and used
6022
// as callee.
6023
if (CGM.getLangOpts().HIP && !CGM.getLangOpts().CUDAIsDevice &&
6024
isa<CUDAKernelCallExpr>(E) &&
6025
(!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
6026
llvm::Value *Handle = Callee.getFunctionPointer();
6027
auto *Stub = Builder.CreateLoad(
6028
Address(Handle, Handle->getType(), CGM.getPointerAlign()));
6029
Callee.setFunctionPointer(Stub);
6030
}
6031
llvm::CallBase *CallOrInvoke = nullptr;
6032
RValue Call = EmitCall(FnInfo, Callee, ReturnValue, Args, &CallOrInvoke,
6033
E == MustTailCall, E->getExprLoc());
6034
6035
// Generate function declaration DISuprogram in order to be used
6036
// in debug info about call sites.
6037
if (CGDebugInfo *DI = getDebugInfo()) {
6038
if (auto *CalleeDecl = dyn_cast_or_null<FunctionDecl>(TargetDecl)) {
6039
FunctionArgList Args;
6040
QualType ResTy = BuildFunctionArgList(CalleeDecl, Args);
6041
DI->EmitFuncDeclForCallSite(CallOrInvoke,
6042
DI->getFunctionType(CalleeDecl, ResTy, Args),
6043
CalleeDecl);
6044
}
6045
}
6046
6047
return Call;
6048
}
6049
6050
LValue CodeGenFunction::
6051
EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
6052
Address BaseAddr = Address::invalid();
6053
if (E->getOpcode() == BO_PtrMemI) {
6054
BaseAddr = EmitPointerWithAlignment(E->getLHS());
6055
} else {
6056
BaseAddr = EmitLValue(E->getLHS()).getAddress();
6057
}
6058
6059
llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
6060
const auto *MPT = E->getRHS()->getType()->castAs<MemberPointerType>();
6061
6062
LValueBaseInfo BaseInfo;
6063
TBAAAccessInfo TBAAInfo;
6064
Address MemberAddr =
6065
EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT, &BaseInfo,
6066
&TBAAInfo);
6067
6068
return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), BaseInfo, TBAAInfo);
6069
}
6070
6071
/// Given the address of a temporary variable, produce an r-value of
6072
/// its type.
6073
RValue CodeGenFunction::convertTempToRValue(Address addr,
6074
QualType type,
6075
SourceLocation loc) {
6076
LValue lvalue = MakeAddrLValue(addr, type, AlignmentSource::Decl);
6077
switch (getEvaluationKind(type)) {
6078
case TEK_Complex:
6079
return RValue::getComplex(EmitLoadOfComplex(lvalue, loc));
6080
case TEK_Aggregate:
6081
return lvalue.asAggregateRValue();
6082
case TEK_Scalar:
6083
return RValue::get(EmitLoadOfScalar(lvalue, loc));
6084
}
6085
llvm_unreachable("bad evaluation kind");
6086
}
6087
6088
void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) {
6089
assert(Val->getType()->isFPOrFPVectorTy());
6090
if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val))
6091
return;
6092
6093
llvm::MDBuilder MDHelper(getLLVMContext());
6094
llvm::MDNode *Node = MDHelper.createFPMath(Accuracy);
6095
6096
cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node);
6097
}
6098
6099
void CodeGenFunction::SetSqrtFPAccuracy(llvm::Value *Val) {
6100
llvm::Type *EltTy = Val->getType()->getScalarType();
6101
if (!EltTy->isFloatTy())
6102
return;
6103
6104
if ((getLangOpts().OpenCL &&
6105
!CGM.getCodeGenOpts().OpenCLCorrectlyRoundedDivSqrt) ||
6106
(getLangOpts().HIP && getLangOpts().CUDAIsDevice &&
6107
!CGM.getCodeGenOpts().HIPCorrectlyRoundedDivSqrt)) {
6108
// OpenCL v1.1 s7.4: minimum accuracy of single precision / is 3ulp
6109
//
6110
// OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt
6111
// build option allows an application to specify that single precision
6112
// floating-point divide (x/y and 1/x) and sqrt used in the program
6113
// source are correctly rounded.
6114
//
6115
// TODO: CUDA has a prec-sqrt flag
6116
SetFPAccuracy(Val, 3.0f);
6117
}
6118
}
6119
6120
void CodeGenFunction::SetDivFPAccuracy(llvm::Value *Val) {
6121
llvm::Type *EltTy = Val->getType()->getScalarType();
6122
if (!EltTy->isFloatTy())
6123
return;
6124
6125
if ((getLangOpts().OpenCL &&
6126
!CGM.getCodeGenOpts().OpenCLCorrectlyRoundedDivSqrt) ||
6127
(getLangOpts().HIP && getLangOpts().CUDAIsDevice &&
6128
!CGM.getCodeGenOpts().HIPCorrectlyRoundedDivSqrt)) {
6129
// OpenCL v1.1 s7.4: minimum accuracy of single precision / is 2.5ulp
6130
//
6131
// OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt
6132
// build option allows an application to specify that single precision
6133
// floating-point divide (x/y and 1/x) and sqrt used in the program
6134
// source are correctly rounded.
6135
//
6136
// TODO: CUDA has a prec-div flag
6137
SetFPAccuracy(Val, 2.5f);
6138
}
6139
}
6140
6141
namespace {
6142
struct LValueOrRValue {
6143
LValue LV;
6144
RValue RV;
6145
};
6146
}
6147
6148
static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF,
6149
const PseudoObjectExpr *E,
6150
bool forLValue,
6151
AggValueSlot slot) {
6152
SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
6153
6154
// Find the result expression, if any.
6155
const Expr *resultExpr = E->getResultExpr();
6156
LValueOrRValue result;
6157
6158
for (PseudoObjectExpr::const_semantics_iterator
6159
i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
6160
const Expr *semantic = *i;
6161
6162
// If this semantic expression is an opaque value, bind it
6163
// to the result of its source expression.
6164
if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
6165
// Skip unique OVEs.
6166
if (ov->isUnique()) {
6167
assert(ov != resultExpr &&
6168
"A unique OVE cannot be used as the result expression");
6169
continue;
6170
}
6171
6172
// If this is the result expression, we may need to evaluate
6173
// directly into the slot.
6174
typedef CodeGenFunction::OpaqueValueMappingData OVMA;
6175
OVMA opaqueData;
6176
if (ov == resultExpr && ov->isPRValue() && !forLValue &&
6177
CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) {
6178
CGF.EmitAggExpr(ov->getSourceExpr(), slot);
6179
LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(),
6180
AlignmentSource::Decl);
6181
opaqueData = OVMA::bind(CGF, ov, LV);
6182
result.RV = slot.asRValue();
6183
6184
// Otherwise, emit as normal.
6185
} else {
6186
opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
6187
6188
// If this is the result, also evaluate the result now.
6189
if (ov == resultExpr) {
6190
if (forLValue)
6191
result.LV = CGF.EmitLValue(ov);
6192
else
6193
result.RV = CGF.EmitAnyExpr(ov, slot);
6194
}
6195
}
6196
6197
opaques.push_back(opaqueData);
6198
6199
// Otherwise, if the expression is the result, evaluate it
6200
// and remember the result.
6201
} else if (semantic == resultExpr) {
6202
if (forLValue)
6203
result.LV = CGF.EmitLValue(semantic);
6204
else
6205
result.RV = CGF.EmitAnyExpr(semantic, slot);
6206
6207
// Otherwise, evaluate the expression in an ignored context.
6208
} else {
6209
CGF.EmitIgnoredExpr(semantic);
6210
}
6211
}
6212
6213
// Unbind all the opaques now.
6214
for (unsigned i = 0, e = opaques.size(); i != e; ++i)
6215
opaques[i].unbind(CGF);
6216
6217
return result;
6218
}
6219
6220
RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E,
6221
AggValueSlot slot) {
6222
return emitPseudoObjectExpr(*this, E, false, slot).RV;
6223
}
6224
6225
LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) {
6226
return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV;
6227
}
6228
6229