forked from OSchip/llvm-project
2762 lines
106 KiB
C++
2762 lines
106 KiB
C++
//===--- CodeGenFunction.cpp - Emit LLVM Code from ASTs for a Function ----===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This coordinates the per-function state used while generating code.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "CodeGenFunction.h"
|
|
#include "CGBlocks.h"
|
|
#include "CGCUDARuntime.h"
|
|
#include "CGCXXABI.h"
|
|
#include "CGCleanup.h"
|
|
#include "CGDebugInfo.h"
|
|
#include "CGOpenMPRuntime.h"
|
|
#include "CodeGenModule.h"
|
|
#include "CodeGenPGO.h"
|
|
#include "TargetInfo.h"
|
|
#include "clang/AST/ASTContext.h"
|
|
#include "clang/AST/ASTLambda.h"
|
|
#include "clang/AST/Attr.h"
|
|
#include "clang/AST/Decl.h"
|
|
#include "clang/AST/DeclCXX.h"
|
|
#include "clang/AST/Expr.h"
|
|
#include "clang/AST/StmtCXX.h"
|
|
#include "clang/AST/StmtObjC.h"
|
|
#include "clang/Basic/Builtins.h"
|
|
#include "clang/Basic/CodeGenOptions.h"
|
|
#include "clang/Basic/TargetInfo.h"
|
|
#include "clang/CodeGen/CGFunctionInfo.h"
|
|
#include "clang/Frontend/FrontendDiagnostic.h"
|
|
#include "llvm/ADT/ArrayRef.h"
|
|
#include "llvm/Frontend/OpenMP/OMPIRBuilder.h"
|
|
#include "llvm/IR/DataLayout.h"
|
|
#include "llvm/IR/Dominators.h"
|
|
#include "llvm/IR/FPEnv.h"
|
|
#include "llvm/IR/IntrinsicInst.h"
|
|
#include "llvm/IR/Intrinsics.h"
|
|
#include "llvm/IR/MDBuilder.h"
|
|
#include "llvm/IR/Operator.h"
|
|
#include "llvm/Support/CRC.h"
|
|
#include "llvm/Transforms/Scalar/LowerExpectIntrinsic.h"
|
|
#include "llvm/Transforms/Utils/PromoteMemToReg.h"
|
|
|
|
using namespace clang;
|
|
using namespace CodeGen;
|
|
|
|
/// shouldEmitLifetimeMarkers - Decide whether we need emit the life-time
|
|
/// markers.
|
|
static bool shouldEmitLifetimeMarkers(const CodeGenOptions &CGOpts,
|
|
const LangOptions &LangOpts) {
|
|
if (CGOpts.DisableLifetimeMarkers)
|
|
return false;
|
|
|
|
// Sanitizers may use markers.
|
|
if (CGOpts.SanitizeAddressUseAfterScope ||
|
|
LangOpts.Sanitize.has(SanitizerKind::HWAddress) ||
|
|
LangOpts.Sanitize.has(SanitizerKind::Memory))
|
|
return true;
|
|
|
|
// For now, only in optimized builds.
|
|
return CGOpts.OptimizationLevel != 0;
|
|
}
|
|
|
|
CodeGenFunction::CodeGenFunction(CodeGenModule &cgm, bool suppressNewContext)
|
|
: CodeGenTypeCache(cgm), CGM(cgm), Target(cgm.getTarget()),
|
|
Builder(cgm, cgm.getModule().getContext(), llvm::ConstantFolder(),
|
|
CGBuilderInserterTy(this)),
|
|
SanOpts(CGM.getLangOpts().Sanitize), CurFPFeatures(CGM.getLangOpts()),
|
|
DebugInfo(CGM.getModuleDebugInfo()), PGO(cgm),
|
|
ShouldEmitLifetimeMarkers(
|
|
shouldEmitLifetimeMarkers(CGM.getCodeGenOpts(), CGM.getLangOpts())) {
|
|
if (!suppressNewContext)
|
|
CGM.getCXXABI().getMangleContext().startNewFunction();
|
|
EHStack.setCGF(this);
|
|
|
|
SetFastMathFlags(CurFPFeatures);
|
|
}
|
|
|
|
CodeGenFunction::~CodeGenFunction() {
|
|
assert(LifetimeExtendedCleanupStack.empty() && "failed to emit a cleanup");
|
|
|
|
if (getLangOpts().OpenMP && CurFn)
|
|
CGM.getOpenMPRuntime().functionFinished(*this);
|
|
|
|
// If we have an OpenMPIRBuilder we want to finalize functions (incl.
|
|
// outlining etc) at some point. Doing it once the function codegen is done
|
|
// seems to be a reasonable spot. We do it here, as opposed to the deletion
|
|
// time of the CodeGenModule, because we have to ensure the IR has not yet
|
|
// been "emitted" to the outside, thus, modifications are still sensible.
|
|
if (CGM.getLangOpts().OpenMPIRBuilder && CurFn)
|
|
CGM.getOpenMPRuntime().getOMPBuilder().finalize(CurFn);
|
|
}
|
|
|
|
// Map the LangOption for exception behavior into
|
|
// the corresponding enum in the IR.
|
|
llvm::fp::ExceptionBehavior
|
|
clang::ToConstrainedExceptMD(LangOptions::FPExceptionModeKind Kind) {
|
|
|
|
switch (Kind) {
|
|
case LangOptions::FPE_Ignore: return llvm::fp::ebIgnore;
|
|
case LangOptions::FPE_MayTrap: return llvm::fp::ebMayTrap;
|
|
case LangOptions::FPE_Strict: return llvm::fp::ebStrict;
|
|
}
|
|
llvm_unreachable("Unsupported FP Exception Behavior");
|
|
}
|
|
|
|
void CodeGenFunction::SetFastMathFlags(FPOptions FPFeatures) {
|
|
llvm::FastMathFlags FMF;
|
|
FMF.setAllowReassoc(FPFeatures.getAllowFPReassociate());
|
|
FMF.setNoNaNs(FPFeatures.getNoHonorNaNs());
|
|
FMF.setNoInfs(FPFeatures.getNoHonorInfs());
|
|
FMF.setNoSignedZeros(FPFeatures.getNoSignedZero());
|
|
FMF.setAllowReciprocal(FPFeatures.getAllowReciprocal());
|
|
FMF.setApproxFunc(FPFeatures.getAllowApproxFunc());
|
|
FMF.setAllowContract(FPFeatures.allowFPContractAcrossStatement());
|
|
Builder.setFastMathFlags(FMF);
|
|
}
|
|
|
|
CodeGenFunction::CGFPOptionsRAII::CGFPOptionsRAII(CodeGenFunction &CGF,
|
|
const Expr *E)
|
|
: CGF(CGF) {
|
|
ConstructorHelper(E->getFPFeaturesInEffect(CGF.getLangOpts()));
|
|
}
|
|
|
|
CodeGenFunction::CGFPOptionsRAII::CGFPOptionsRAII(CodeGenFunction &CGF,
|
|
FPOptions FPFeatures)
|
|
: CGF(CGF) {
|
|
ConstructorHelper(FPFeatures);
|
|
}
|
|
|
|
void CodeGenFunction::CGFPOptionsRAII::ConstructorHelper(FPOptions FPFeatures) {
|
|
OldFPFeatures = CGF.CurFPFeatures;
|
|
CGF.CurFPFeatures = FPFeatures;
|
|
|
|
OldExcept = CGF.Builder.getDefaultConstrainedExcept();
|
|
OldRounding = CGF.Builder.getDefaultConstrainedRounding();
|
|
|
|
if (OldFPFeatures == FPFeatures)
|
|
return;
|
|
|
|
FMFGuard.emplace(CGF.Builder);
|
|
|
|
llvm::RoundingMode NewRoundingBehavior =
|
|
static_cast<llvm::RoundingMode>(FPFeatures.getRoundingMode());
|
|
CGF.Builder.setDefaultConstrainedRounding(NewRoundingBehavior);
|
|
auto NewExceptionBehavior =
|
|
ToConstrainedExceptMD(static_cast<LangOptions::FPExceptionModeKind>(
|
|
FPFeatures.getFPExceptionMode()));
|
|
CGF.Builder.setDefaultConstrainedExcept(NewExceptionBehavior);
|
|
|
|
CGF.SetFastMathFlags(FPFeatures);
|
|
|
|
assert((CGF.CurFuncDecl == nullptr || CGF.Builder.getIsFPConstrained() ||
|
|
isa<CXXConstructorDecl>(CGF.CurFuncDecl) ||
|
|
isa<CXXDestructorDecl>(CGF.CurFuncDecl) ||
|
|
(NewExceptionBehavior == llvm::fp::ebIgnore &&
|
|
NewRoundingBehavior == llvm::RoundingMode::NearestTiesToEven)) &&
|
|
"FPConstrained should be enabled on entire function");
|
|
|
|
auto mergeFnAttrValue = [&](StringRef Name, bool Value) {
|
|
auto OldValue =
|
|
CGF.CurFn->getFnAttribute(Name).getValueAsBool();
|
|
auto NewValue = OldValue & Value;
|
|
if (OldValue != NewValue)
|
|
CGF.CurFn->addFnAttr(Name, llvm::toStringRef(NewValue));
|
|
};
|
|
mergeFnAttrValue("no-infs-fp-math", FPFeatures.getNoHonorInfs());
|
|
mergeFnAttrValue("no-nans-fp-math", FPFeatures.getNoHonorNaNs());
|
|
mergeFnAttrValue("no-signed-zeros-fp-math", FPFeatures.getNoSignedZero());
|
|
mergeFnAttrValue("unsafe-fp-math", FPFeatures.getAllowFPReassociate() &&
|
|
FPFeatures.getAllowReciprocal() &&
|
|
FPFeatures.getAllowApproxFunc() &&
|
|
FPFeatures.getNoSignedZero());
|
|
}
|
|
|
|
CodeGenFunction::CGFPOptionsRAII::~CGFPOptionsRAII() {
|
|
CGF.CurFPFeatures = OldFPFeatures;
|
|
CGF.Builder.setDefaultConstrainedExcept(OldExcept);
|
|
CGF.Builder.setDefaultConstrainedRounding(OldRounding);
|
|
}
|
|
|
|
LValue CodeGenFunction::MakeNaturalAlignAddrLValue(llvm::Value *V, QualType T) {
|
|
LValueBaseInfo BaseInfo;
|
|
TBAAAccessInfo TBAAInfo;
|
|
CharUnits Alignment = CGM.getNaturalTypeAlignment(T, &BaseInfo, &TBAAInfo);
|
|
Address Addr(V, ConvertTypeForMem(T), Alignment);
|
|
return LValue::MakeAddr(Addr, T, getContext(), BaseInfo, TBAAInfo);
|
|
}
|
|
|
|
/// Given a value of type T* that may not be to a complete object,
|
|
/// construct an l-value with the natural pointee alignment of T.
|
|
LValue
|
|
CodeGenFunction::MakeNaturalAlignPointeeAddrLValue(llvm::Value *V, QualType T) {
|
|
LValueBaseInfo BaseInfo;
|
|
TBAAAccessInfo TBAAInfo;
|
|
CharUnits Align = CGM.getNaturalTypeAlignment(T, &BaseInfo, &TBAAInfo,
|
|
/* forPointeeType= */ true);
|
|
Address Addr(V, ConvertTypeForMem(T), Align);
|
|
return MakeAddrLValue(Addr, T, BaseInfo, TBAAInfo);
|
|
}
|
|
|
|
|
|
llvm::Type *CodeGenFunction::ConvertTypeForMem(QualType T) {
|
|
return CGM.getTypes().ConvertTypeForMem(T);
|
|
}
|
|
|
|
llvm::Type *CodeGenFunction::ConvertType(QualType T) {
|
|
return CGM.getTypes().ConvertType(T);
|
|
}
|
|
|
|
TypeEvaluationKind CodeGenFunction::getEvaluationKind(QualType type) {
|
|
type = type.getCanonicalType();
|
|
while (true) {
|
|
switch (type->getTypeClass()) {
|
|
#define TYPE(name, parent)
|
|
#define ABSTRACT_TYPE(name, parent)
|
|
#define NON_CANONICAL_TYPE(name, parent) case Type::name:
|
|
#define DEPENDENT_TYPE(name, parent) case Type::name:
|
|
#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(name, parent) case Type::name:
|
|
#include "clang/AST/TypeNodes.inc"
|
|
llvm_unreachable("non-canonical or dependent type in IR-generation");
|
|
|
|
case Type::Auto:
|
|
case Type::DeducedTemplateSpecialization:
|
|
llvm_unreachable("undeduced type in IR-generation");
|
|
|
|
// Various scalar types.
|
|
case Type::Builtin:
|
|
case Type::Pointer:
|
|
case Type::BlockPointer:
|
|
case Type::LValueReference:
|
|
case Type::RValueReference:
|
|
case Type::MemberPointer:
|
|
case Type::Vector:
|
|
case Type::ExtVector:
|
|
case Type::ConstantMatrix:
|
|
case Type::FunctionProto:
|
|
case Type::FunctionNoProto:
|
|
case Type::Enum:
|
|
case Type::ObjCObjectPointer:
|
|
case Type::Pipe:
|
|
case Type::BitInt:
|
|
return TEK_Scalar;
|
|
|
|
// Complexes.
|
|
case Type::Complex:
|
|
return TEK_Complex;
|
|
|
|
// Arrays, records, and Objective-C objects.
|
|
case Type::ConstantArray:
|
|
case Type::IncompleteArray:
|
|
case Type::VariableArray:
|
|
case Type::Record:
|
|
case Type::ObjCObject:
|
|
case Type::ObjCInterface:
|
|
return TEK_Aggregate;
|
|
|
|
// We operate on atomic values according to their underlying type.
|
|
case Type::Atomic:
|
|
type = cast<AtomicType>(type)->getValueType();
|
|
continue;
|
|
}
|
|
llvm_unreachable("unknown type kind!");
|
|
}
|
|
}
|
|
|
|
llvm::DebugLoc CodeGenFunction::EmitReturnBlock() {
|
|
// For cleanliness, we try to avoid emitting the return block for
|
|
// simple cases.
|
|
llvm::BasicBlock *CurBB = Builder.GetInsertBlock();
|
|
|
|
if (CurBB) {
|
|
assert(!CurBB->getTerminator() && "Unexpected terminated block.");
|
|
|
|
// We have a valid insert point, reuse it if it is empty or there are no
|
|
// explicit jumps to the return block.
|
|
if (CurBB->empty() || ReturnBlock.getBlock()->use_empty()) {
|
|
ReturnBlock.getBlock()->replaceAllUsesWith(CurBB);
|
|
delete ReturnBlock.getBlock();
|
|
ReturnBlock = JumpDest();
|
|
} else
|
|
EmitBlock(ReturnBlock.getBlock());
|
|
return llvm::DebugLoc();
|
|
}
|
|
|
|
// Otherwise, if the return block is the target of a single direct
|
|
// branch then we can just put the code in that block instead. This
|
|
// cleans up functions which started with a unified return block.
|
|
if (ReturnBlock.getBlock()->hasOneUse()) {
|
|
llvm::BranchInst *BI =
|
|
dyn_cast<llvm::BranchInst>(*ReturnBlock.getBlock()->user_begin());
|
|
if (BI && BI->isUnconditional() &&
|
|
BI->getSuccessor(0) == ReturnBlock.getBlock()) {
|
|
// Record/return the DebugLoc of the simple 'return' expression to be used
|
|
// later by the actual 'ret' instruction.
|
|
llvm::DebugLoc Loc = BI->getDebugLoc();
|
|
Builder.SetInsertPoint(BI->getParent());
|
|
BI->eraseFromParent();
|
|
delete ReturnBlock.getBlock();
|
|
ReturnBlock = JumpDest();
|
|
return Loc;
|
|
}
|
|
}
|
|
|
|
// FIXME: We are at an unreachable point, there is no reason to emit the block
|
|
// unless it has uses. However, we still need a place to put the debug
|
|
// region.end for now.
|
|
|
|
EmitBlock(ReturnBlock.getBlock());
|
|
return llvm::DebugLoc();
|
|
}
|
|
|
|
static void EmitIfUsed(CodeGenFunction &CGF, llvm::BasicBlock *BB) {
|
|
if (!BB) return;
|
|
if (!BB->use_empty())
|
|
return CGF.CurFn->getBasicBlockList().push_back(BB);
|
|
delete BB;
|
|
}
|
|
|
|
void CodeGenFunction::FinishFunction(SourceLocation EndLoc) {
|
|
assert(BreakContinueStack.empty() &&
|
|
"mismatched push/pop in break/continue stack!");
|
|
|
|
bool OnlySimpleReturnStmts = NumSimpleReturnExprs > 0
|
|
&& NumSimpleReturnExprs == NumReturnExprs
|
|
&& ReturnBlock.getBlock()->use_empty();
|
|
// Usually the return expression is evaluated before the cleanup
|
|
// code. If the function contains only a simple return statement,
|
|
// such as a constant, the location before the cleanup code becomes
|
|
// the last useful breakpoint in the function, because the simple
|
|
// return expression will be evaluated after the cleanup code. To be
|
|
// safe, set the debug location for cleanup code to the location of
|
|
// the return statement. Otherwise the cleanup code should be at the
|
|
// end of the function's lexical scope.
|
|
//
|
|
// If there are multiple branches to the return block, the branch
|
|
// instructions will get the location of the return statements and
|
|
// all will be fine.
|
|
if (CGDebugInfo *DI = getDebugInfo()) {
|
|
if (OnlySimpleReturnStmts)
|
|
DI->EmitLocation(Builder, LastStopPoint);
|
|
else
|
|
DI->EmitLocation(Builder, EndLoc);
|
|
}
|
|
|
|
// Pop any cleanups that might have been associated with the
|
|
// parameters. Do this in whatever block we're currently in; it's
|
|
// important to do this before we enter the return block or return
|
|
// edges will be *really* confused.
|
|
bool HasCleanups = EHStack.stable_begin() != PrologueCleanupDepth;
|
|
bool HasOnlyLifetimeMarkers =
|
|
HasCleanups && EHStack.containsOnlyLifetimeMarkers(PrologueCleanupDepth);
|
|
bool EmitRetDbgLoc = !HasCleanups || HasOnlyLifetimeMarkers;
|
|
if (HasCleanups) {
|
|
// Make sure the line table doesn't jump back into the body for
|
|
// the ret after it's been at EndLoc.
|
|
Optional<ApplyDebugLocation> AL;
|
|
if (CGDebugInfo *DI = getDebugInfo()) {
|
|
if (OnlySimpleReturnStmts)
|
|
DI->EmitLocation(Builder, EndLoc);
|
|
else
|
|
// We may not have a valid end location. Try to apply it anyway, and
|
|
// fall back to an artificial location if needed.
|
|
AL = ApplyDebugLocation::CreateDefaultArtificial(*this, EndLoc);
|
|
}
|
|
|
|
PopCleanupBlocks(PrologueCleanupDepth);
|
|
}
|
|
|
|
// Emit function epilog (to return).
|
|
llvm::DebugLoc Loc = EmitReturnBlock();
|
|
|
|
if (ShouldInstrumentFunction()) {
|
|
if (CGM.getCodeGenOpts().InstrumentFunctions)
|
|
CurFn->addFnAttr("instrument-function-exit", "__cyg_profile_func_exit");
|
|
if (CGM.getCodeGenOpts().InstrumentFunctionsAfterInlining)
|
|
CurFn->addFnAttr("instrument-function-exit-inlined",
|
|
"__cyg_profile_func_exit");
|
|
}
|
|
|
|
if (ShouldSkipSanitizerInstrumentation())
|
|
CurFn->addFnAttr(llvm::Attribute::DisableSanitizerInstrumentation);
|
|
|
|
// Emit debug descriptor for function end.
|
|
if (CGDebugInfo *DI = getDebugInfo())
|
|
DI->EmitFunctionEnd(Builder, CurFn);
|
|
|
|
// Reset the debug location to that of the simple 'return' expression, if any
|
|
// rather than that of the end of the function's scope '}'.
|
|
ApplyDebugLocation AL(*this, Loc);
|
|
EmitFunctionEpilog(*CurFnInfo, EmitRetDbgLoc, EndLoc);
|
|
EmitEndEHSpec(CurCodeDecl);
|
|
|
|
assert(EHStack.empty() &&
|
|
"did not remove all scopes from cleanup stack!");
|
|
|
|
// If someone did an indirect goto, emit the indirect goto block at the end of
|
|
// the function.
|
|
if (IndirectBranch) {
|
|
EmitBlock(IndirectBranch->getParent());
|
|
Builder.ClearInsertionPoint();
|
|
}
|
|
|
|
// If some of our locals escaped, insert a call to llvm.localescape in the
|
|
// entry block.
|
|
if (!EscapedLocals.empty()) {
|
|
// Invert the map from local to index into a simple vector. There should be
|
|
// no holes.
|
|
SmallVector<llvm::Value *, 4> EscapeArgs;
|
|
EscapeArgs.resize(EscapedLocals.size());
|
|
for (auto &Pair : EscapedLocals)
|
|
EscapeArgs[Pair.second] = Pair.first;
|
|
llvm::Function *FrameEscapeFn = llvm::Intrinsic::getDeclaration(
|
|
&CGM.getModule(), llvm::Intrinsic::localescape);
|
|
CGBuilderTy(*this, AllocaInsertPt).CreateCall(FrameEscapeFn, EscapeArgs);
|
|
}
|
|
|
|
// Remove the AllocaInsertPt instruction, which is just a convenience for us.
|
|
llvm::Instruction *Ptr = AllocaInsertPt;
|
|
AllocaInsertPt = nullptr;
|
|
Ptr->eraseFromParent();
|
|
|
|
// PostAllocaInsertPt, if created, was lazily created when it was required,
|
|
// remove it now since it was just created for our own convenience.
|
|
if (PostAllocaInsertPt) {
|
|
llvm::Instruction *PostPtr = PostAllocaInsertPt;
|
|
PostAllocaInsertPt = nullptr;
|
|
PostPtr->eraseFromParent();
|
|
}
|
|
|
|
// If someone took the address of a label but never did an indirect goto, we
|
|
// made a zero entry PHI node, which is illegal, zap it now.
|
|
if (IndirectBranch) {
|
|
llvm::PHINode *PN = cast<llvm::PHINode>(IndirectBranch->getAddress());
|
|
if (PN->getNumIncomingValues() == 0) {
|
|
PN->replaceAllUsesWith(llvm::UndefValue::get(PN->getType()));
|
|
PN->eraseFromParent();
|
|
}
|
|
}
|
|
|
|
EmitIfUsed(*this, EHResumeBlock);
|
|
EmitIfUsed(*this, TerminateLandingPad);
|
|
EmitIfUsed(*this, TerminateHandler);
|
|
EmitIfUsed(*this, UnreachableBlock);
|
|
|
|
for (const auto &FuncletAndParent : TerminateFunclets)
|
|
EmitIfUsed(*this, FuncletAndParent.second);
|
|
|
|
if (CGM.getCodeGenOpts().EmitDeclMetadata)
|
|
EmitDeclMetadata();
|
|
|
|
for (const auto &R : DeferredReplacements) {
|
|
if (llvm::Value *Old = R.first) {
|
|
Old->replaceAllUsesWith(R.second);
|
|
cast<llvm::Instruction>(Old)->eraseFromParent();
|
|
}
|
|
}
|
|
DeferredReplacements.clear();
|
|
|
|
// Eliminate CleanupDestSlot alloca by replacing it with SSA values and
|
|
// PHIs if the current function is a coroutine. We don't do it for all
|
|
// functions as it may result in slight increase in numbers of instructions
|
|
// if compiled with no optimizations. We do it for coroutine as the lifetime
|
|
// of CleanupDestSlot alloca make correct coroutine frame building very
|
|
// difficult.
|
|
if (NormalCleanupDest.isValid() && isCoroutine()) {
|
|
llvm::DominatorTree DT(*CurFn);
|
|
llvm::PromoteMemToReg(
|
|
cast<llvm::AllocaInst>(NormalCleanupDest.getPointer()), DT);
|
|
NormalCleanupDest = Address::invalid();
|
|
}
|
|
|
|
// Scan function arguments for vector width.
|
|
for (llvm::Argument &A : CurFn->args())
|
|
if (auto *VT = dyn_cast<llvm::VectorType>(A.getType()))
|
|
LargestVectorWidth =
|
|
std::max((uint64_t)LargestVectorWidth,
|
|
VT->getPrimitiveSizeInBits().getKnownMinSize());
|
|
|
|
// Update vector width based on return type.
|
|
if (auto *VT = dyn_cast<llvm::VectorType>(CurFn->getReturnType()))
|
|
LargestVectorWidth =
|
|
std::max((uint64_t)LargestVectorWidth,
|
|
VT->getPrimitiveSizeInBits().getKnownMinSize());
|
|
|
|
// Add the required-vector-width attribute. This contains the max width from:
|
|
// 1. min-vector-width attribute used in the source program.
|
|
// 2. Any builtins used that have a vector width specified.
|
|
// 3. Values passed in and out of inline assembly.
|
|
// 4. Width of vector arguments and return types for this function.
|
|
// 5. Width of vector aguments and return types for functions called by this
|
|
// function.
|
|
CurFn->addFnAttr("min-legal-vector-width", llvm::utostr(LargestVectorWidth));
|
|
|
|
// Add vscale_range attribute if appropriate.
|
|
Optional<std::pair<unsigned, unsigned>> VScaleRange =
|
|
getContext().getTargetInfo().getVScaleRange(getLangOpts());
|
|
if (VScaleRange) {
|
|
CurFn->addFnAttr(llvm::Attribute::getWithVScaleRangeArgs(
|
|
getLLVMContext(), VScaleRange.getValue().first,
|
|
VScaleRange.getValue().second));
|
|
}
|
|
|
|
// If we generated an unreachable return block, delete it now.
|
|
if (ReturnBlock.isValid() && ReturnBlock.getBlock()->use_empty()) {
|
|
Builder.ClearInsertionPoint();
|
|
ReturnBlock.getBlock()->eraseFromParent();
|
|
}
|
|
if (ReturnValue.isValid()) {
|
|
auto *RetAlloca = dyn_cast<llvm::AllocaInst>(ReturnValue.getPointer());
|
|
if (RetAlloca && RetAlloca->use_empty()) {
|
|
RetAlloca->eraseFromParent();
|
|
ReturnValue = Address::invalid();
|
|
}
|
|
}
|
|
}
|
|
|
|
/// ShouldInstrumentFunction - Return true if the current function should be
|
|
/// instrumented with __cyg_profile_func_* calls
|
|
bool CodeGenFunction::ShouldInstrumentFunction() {
|
|
if (!CGM.getCodeGenOpts().InstrumentFunctions &&
|
|
!CGM.getCodeGenOpts().InstrumentFunctionsAfterInlining &&
|
|
!CGM.getCodeGenOpts().InstrumentFunctionEntryBare)
|
|
return false;
|
|
if (!CurFuncDecl || CurFuncDecl->hasAttr<NoInstrumentFunctionAttr>())
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
bool CodeGenFunction::ShouldSkipSanitizerInstrumentation() {
|
|
if (!CurFuncDecl)
|
|
return false;
|
|
return CurFuncDecl->hasAttr<DisableSanitizerInstrumentationAttr>();
|
|
}
|
|
|
|
/// ShouldXRayInstrument - Return true if the current function should be
|
|
/// instrumented with XRay nop sleds.
|
|
bool CodeGenFunction::ShouldXRayInstrumentFunction() const {
|
|
return CGM.getCodeGenOpts().XRayInstrumentFunctions;
|
|
}
|
|
|
|
/// AlwaysEmitXRayCustomEvents - Return true if we should emit IR for calls to
|
|
/// the __xray_customevent(...) builtin calls, when doing XRay instrumentation.
|
|
bool CodeGenFunction::AlwaysEmitXRayCustomEvents() const {
|
|
return CGM.getCodeGenOpts().XRayInstrumentFunctions &&
|
|
(CGM.getCodeGenOpts().XRayAlwaysEmitCustomEvents ||
|
|
CGM.getCodeGenOpts().XRayInstrumentationBundle.Mask ==
|
|
XRayInstrKind::Custom);
|
|
}
|
|
|
|
bool CodeGenFunction::AlwaysEmitXRayTypedEvents() const {
|
|
return CGM.getCodeGenOpts().XRayInstrumentFunctions &&
|
|
(CGM.getCodeGenOpts().XRayAlwaysEmitTypedEvents ||
|
|
CGM.getCodeGenOpts().XRayInstrumentationBundle.Mask ==
|
|
XRayInstrKind::Typed);
|
|
}
|
|
|
|
llvm::Constant *
|
|
CodeGenFunction::EncodeAddrForUseInPrologue(llvm::Function *F,
|
|
llvm::Constant *Addr) {
|
|
// Addresses stored in prologue data can't require run-time fixups and must
|
|
// be PC-relative. Run-time fixups are undesirable because they necessitate
|
|
// writable text segments, which are unsafe. And absolute addresses are
|
|
// undesirable because they break PIE mode.
|
|
|
|
// Add a layer of indirection through a private global. Taking its address
|
|
// won't result in a run-time fixup, even if Addr has linkonce_odr linkage.
|
|
auto *GV = new llvm::GlobalVariable(CGM.getModule(), Addr->getType(),
|
|
/*isConstant=*/true,
|
|
llvm::GlobalValue::PrivateLinkage, Addr);
|
|
|
|
// Create a PC-relative address.
|
|
auto *GOTAsInt = llvm::ConstantExpr::getPtrToInt(GV, IntPtrTy);
|
|
auto *FuncAsInt = llvm::ConstantExpr::getPtrToInt(F, IntPtrTy);
|
|
auto *PCRelAsInt = llvm::ConstantExpr::getSub(GOTAsInt, FuncAsInt);
|
|
return (IntPtrTy == Int32Ty)
|
|
? PCRelAsInt
|
|
: llvm::ConstantExpr::getTrunc(PCRelAsInt, Int32Ty);
|
|
}
|
|
|
|
llvm::Value *
|
|
CodeGenFunction::DecodeAddrUsedInPrologue(llvm::Value *F,
|
|
llvm::Value *EncodedAddr) {
|
|
// Reconstruct the address of the global.
|
|
auto *PCRelAsInt = Builder.CreateSExt(EncodedAddr, IntPtrTy);
|
|
auto *FuncAsInt = Builder.CreatePtrToInt(F, IntPtrTy, "func_addr.int");
|
|
auto *GOTAsInt = Builder.CreateAdd(PCRelAsInt, FuncAsInt, "global_addr.int");
|
|
auto *GOTAddr = Builder.CreateIntToPtr(GOTAsInt, Int8PtrPtrTy, "global_addr");
|
|
|
|
// Load the original pointer through the global.
|
|
return Builder.CreateLoad(Address(GOTAddr, getPointerAlign()),
|
|
"decoded_addr");
|
|
}
|
|
|
|
void CodeGenFunction::EmitOpenCLKernelMetadata(const FunctionDecl *FD,
|
|
llvm::Function *Fn)
|
|
{
|
|
if (!FD->hasAttr<OpenCLKernelAttr>())
|
|
return;
|
|
|
|
llvm::LLVMContext &Context = getLLVMContext();
|
|
|
|
CGM.GenOpenCLArgMetadata(Fn, FD, this);
|
|
|
|
if (const VecTypeHintAttr *A = FD->getAttr<VecTypeHintAttr>()) {
|
|
QualType HintQTy = A->getTypeHint();
|
|
const ExtVectorType *HintEltQTy = HintQTy->getAs<ExtVectorType>();
|
|
bool IsSignedInteger =
|
|
HintQTy->isSignedIntegerType() ||
|
|
(HintEltQTy && HintEltQTy->getElementType()->isSignedIntegerType());
|
|
llvm::Metadata *AttrMDArgs[] = {
|
|
llvm::ConstantAsMetadata::get(llvm::UndefValue::get(
|
|
CGM.getTypes().ConvertType(A->getTypeHint()))),
|
|
llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
|
|
llvm::IntegerType::get(Context, 32),
|
|
llvm::APInt(32, (uint64_t)(IsSignedInteger ? 1 : 0))))};
|
|
Fn->setMetadata("vec_type_hint", llvm::MDNode::get(Context, AttrMDArgs));
|
|
}
|
|
|
|
if (const WorkGroupSizeHintAttr *A = FD->getAttr<WorkGroupSizeHintAttr>()) {
|
|
llvm::Metadata *AttrMDArgs[] = {
|
|
llvm::ConstantAsMetadata::get(Builder.getInt32(A->getXDim())),
|
|
llvm::ConstantAsMetadata::get(Builder.getInt32(A->getYDim())),
|
|
llvm::ConstantAsMetadata::get(Builder.getInt32(A->getZDim()))};
|
|
Fn->setMetadata("work_group_size_hint", llvm::MDNode::get(Context, AttrMDArgs));
|
|
}
|
|
|
|
if (const ReqdWorkGroupSizeAttr *A = FD->getAttr<ReqdWorkGroupSizeAttr>()) {
|
|
llvm::Metadata *AttrMDArgs[] = {
|
|
llvm::ConstantAsMetadata::get(Builder.getInt32(A->getXDim())),
|
|
llvm::ConstantAsMetadata::get(Builder.getInt32(A->getYDim())),
|
|
llvm::ConstantAsMetadata::get(Builder.getInt32(A->getZDim()))};
|
|
Fn->setMetadata("reqd_work_group_size", llvm::MDNode::get(Context, AttrMDArgs));
|
|
}
|
|
|
|
if (const OpenCLIntelReqdSubGroupSizeAttr *A =
|
|
FD->getAttr<OpenCLIntelReqdSubGroupSizeAttr>()) {
|
|
llvm::Metadata *AttrMDArgs[] = {
|
|
llvm::ConstantAsMetadata::get(Builder.getInt32(A->getSubGroupSize()))};
|
|
Fn->setMetadata("intel_reqd_sub_group_size",
|
|
llvm::MDNode::get(Context, AttrMDArgs));
|
|
}
|
|
}
|
|
|
|
/// Determine whether the function F ends with a return stmt.
|
|
static bool endsWithReturn(const Decl* F) {
|
|
const Stmt *Body = nullptr;
|
|
if (auto *FD = dyn_cast_or_null<FunctionDecl>(F))
|
|
Body = FD->getBody();
|
|
else if (auto *OMD = dyn_cast_or_null<ObjCMethodDecl>(F))
|
|
Body = OMD->getBody();
|
|
|
|
if (auto *CS = dyn_cast_or_null<CompoundStmt>(Body)) {
|
|
auto LastStmt = CS->body_rbegin();
|
|
if (LastStmt != CS->body_rend())
|
|
return isa<ReturnStmt>(*LastStmt);
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void CodeGenFunction::markAsIgnoreThreadCheckingAtRuntime(llvm::Function *Fn) {
|
|
if (SanOpts.has(SanitizerKind::Thread)) {
|
|
Fn->addFnAttr("sanitize_thread_no_checking_at_run_time");
|
|
Fn->removeFnAttr(llvm::Attribute::SanitizeThread);
|
|
}
|
|
}
|
|
|
|
/// Check if the return value of this function requires sanitization.
|
|
bool CodeGenFunction::requiresReturnValueCheck() const {
|
|
return requiresReturnValueNullabilityCheck() ||
|
|
(SanOpts.has(SanitizerKind::ReturnsNonnullAttribute) && CurCodeDecl &&
|
|
CurCodeDecl->getAttr<ReturnsNonNullAttr>());
|
|
}
|
|
|
|
static bool matchesStlAllocatorFn(const Decl *D, const ASTContext &Ctx) {
|
|
auto *MD = dyn_cast_or_null<CXXMethodDecl>(D);
|
|
if (!MD || !MD->getDeclName().getAsIdentifierInfo() ||
|
|
!MD->getDeclName().getAsIdentifierInfo()->isStr("allocate") ||
|
|
(MD->getNumParams() != 1 && MD->getNumParams() != 2))
|
|
return false;
|
|
|
|
if (MD->parameters()[0]->getType().getCanonicalType() != Ctx.getSizeType())
|
|
return false;
|
|
|
|
if (MD->getNumParams() == 2) {
|
|
auto *PT = MD->parameters()[1]->getType()->getAs<PointerType>();
|
|
if (!PT || !PT->isVoidPointerType() ||
|
|
!PT->getPointeeType().isConstQualified())
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/// Return the UBSan prologue signature for \p FD if one is available.
|
|
static llvm::Constant *getPrologueSignature(CodeGenModule &CGM,
|
|
const FunctionDecl *FD) {
|
|
if (const auto *MD = dyn_cast<CXXMethodDecl>(FD))
|
|
if (!MD->isStatic())
|
|
return nullptr;
|
|
return CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM);
|
|
}
|
|
|
|
void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
|
|
llvm::Function *Fn,
|
|
const CGFunctionInfo &FnInfo,
|
|
const FunctionArgList &Args,
|
|
SourceLocation Loc,
|
|
SourceLocation StartLoc) {
|
|
assert(!CurFn &&
|
|
"Do not use a CodeGenFunction object for more than one function");
|
|
|
|
const Decl *D = GD.getDecl();
|
|
|
|
DidCallStackSave = false;
|
|
CurCodeDecl = D;
|
|
const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(D);
|
|
if (FD && FD->usesSEHTry())
|
|
CurSEHParent = FD;
|
|
CurFuncDecl = (D ? D->getNonClosureContext() : nullptr);
|
|
FnRetTy = RetTy;
|
|
CurFn = Fn;
|
|
CurFnInfo = &FnInfo;
|
|
assert(CurFn->isDeclaration() && "Function already has body?");
|
|
|
|
// If this function is ignored for any of the enabled sanitizers,
|
|
// disable the sanitizer for the function.
|
|
do {
|
|
#define SANITIZER(NAME, ID) \
|
|
if (SanOpts.empty()) \
|
|
break; \
|
|
if (SanOpts.has(SanitizerKind::ID)) \
|
|
if (CGM.isInNoSanitizeList(SanitizerKind::ID, Fn, Loc)) \
|
|
SanOpts.set(SanitizerKind::ID, false);
|
|
|
|
#include "clang/Basic/Sanitizers.def"
|
|
#undef SANITIZER
|
|
} while (false);
|
|
|
|
if (D) {
|
|
bool NoSanitizeCoverage = false;
|
|
|
|
for (auto Attr : D->specific_attrs<NoSanitizeAttr>()) {
|
|
// Apply the no_sanitize* attributes to SanOpts.
|
|
SanitizerMask mask = Attr->getMask();
|
|
SanOpts.Mask &= ~mask;
|
|
if (mask & SanitizerKind::Address)
|
|
SanOpts.set(SanitizerKind::KernelAddress, false);
|
|
if (mask & SanitizerKind::KernelAddress)
|
|
SanOpts.set(SanitizerKind::Address, false);
|
|
if (mask & SanitizerKind::HWAddress)
|
|
SanOpts.set(SanitizerKind::KernelHWAddress, false);
|
|
if (mask & SanitizerKind::KernelHWAddress)
|
|
SanOpts.set(SanitizerKind::HWAddress, false);
|
|
|
|
// SanitizeCoverage is not handled by SanOpts.
|
|
if (Attr->hasCoverage())
|
|
NoSanitizeCoverage = true;
|
|
}
|
|
|
|
if (NoSanitizeCoverage && CGM.getCodeGenOpts().hasSanitizeCoverage())
|
|
Fn->addFnAttr(llvm::Attribute::NoSanitizeCoverage);
|
|
}
|
|
|
|
// Apply sanitizer attributes to the function.
|
|
if (SanOpts.hasOneOf(SanitizerKind::Address | SanitizerKind::KernelAddress))
|
|
Fn->addFnAttr(llvm::Attribute::SanitizeAddress);
|
|
if (SanOpts.hasOneOf(SanitizerKind::HWAddress |
|
|
SanitizerKind::KernelHWAddress))
|
|
Fn->addFnAttr(llvm::Attribute::SanitizeHWAddress);
|
|
if (SanOpts.has(SanitizerKind::MemTag))
|
|
Fn->addFnAttr(llvm::Attribute::SanitizeMemTag);
|
|
if (SanOpts.has(SanitizerKind::Thread))
|
|
Fn->addFnAttr(llvm::Attribute::SanitizeThread);
|
|
if (SanOpts.hasOneOf(SanitizerKind::Memory | SanitizerKind::KernelMemory))
|
|
Fn->addFnAttr(llvm::Attribute::SanitizeMemory);
|
|
if (SanOpts.has(SanitizerKind::SafeStack))
|
|
Fn->addFnAttr(llvm::Attribute::SafeStack);
|
|
if (SanOpts.has(SanitizerKind::ShadowCallStack))
|
|
Fn->addFnAttr(llvm::Attribute::ShadowCallStack);
|
|
|
|
// Apply fuzzing attribute to the function.
|
|
if (SanOpts.hasOneOf(SanitizerKind::Fuzzer | SanitizerKind::FuzzerNoLink))
|
|
Fn->addFnAttr(llvm::Attribute::OptForFuzzing);
|
|
|
|
// Ignore TSan memory acesses from within ObjC/ObjC++ dealloc, initialize,
|
|
// .cxx_destruct, __destroy_helper_block_ and all of their calees at run time.
|
|
if (SanOpts.has(SanitizerKind::Thread)) {
|
|
if (const auto *OMD = dyn_cast_or_null<ObjCMethodDecl>(D)) {
|
|
IdentifierInfo *II = OMD->getSelector().getIdentifierInfoForSlot(0);
|
|
if (OMD->getMethodFamily() == OMF_dealloc ||
|
|
OMD->getMethodFamily() == OMF_initialize ||
|
|
(OMD->getSelector().isUnarySelector() && II->isStr(".cxx_destruct"))) {
|
|
markAsIgnoreThreadCheckingAtRuntime(Fn);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Ignore unrelated casts in STL allocate() since the allocator must cast
|
|
// from void* to T* before object initialization completes. Don't match on the
|
|
// namespace because not all allocators are in std::
|
|
if (D && SanOpts.has(SanitizerKind::CFIUnrelatedCast)) {
|
|
if (matchesStlAllocatorFn(D, getContext()))
|
|
SanOpts.Mask &= ~SanitizerKind::CFIUnrelatedCast;
|
|
}
|
|
|
|
// Ignore null checks in coroutine functions since the coroutines passes
|
|
// are not aware of how to move the extra UBSan instructions across the split
|
|
// coroutine boundaries.
|
|
if (D && SanOpts.has(SanitizerKind::Null))
|
|
if (FD && FD->getBody() &&
|
|
FD->getBody()->getStmtClass() == Stmt::CoroutineBodyStmtClass)
|
|
SanOpts.Mask &= ~SanitizerKind::Null;
|
|
|
|
// Apply xray attributes to the function (as a string, for now)
|
|
bool AlwaysXRayAttr = false;
|
|
if (const auto *XRayAttr = D ? D->getAttr<XRayInstrumentAttr>() : nullptr) {
|
|
if (CGM.getCodeGenOpts().XRayInstrumentationBundle.has(
|
|
XRayInstrKind::FunctionEntry) ||
|
|
CGM.getCodeGenOpts().XRayInstrumentationBundle.has(
|
|
XRayInstrKind::FunctionExit)) {
|
|
if (XRayAttr->alwaysXRayInstrument() && ShouldXRayInstrumentFunction()) {
|
|
Fn->addFnAttr("function-instrument", "xray-always");
|
|
AlwaysXRayAttr = true;
|
|
}
|
|
if (XRayAttr->neverXRayInstrument())
|
|
Fn->addFnAttr("function-instrument", "xray-never");
|
|
if (const auto *LogArgs = D->getAttr<XRayLogArgsAttr>())
|
|
if (ShouldXRayInstrumentFunction())
|
|
Fn->addFnAttr("xray-log-args",
|
|
llvm::utostr(LogArgs->getArgumentCount()));
|
|
}
|
|
} else {
|
|
if (ShouldXRayInstrumentFunction() && !CGM.imbueXRayAttrs(Fn, Loc))
|
|
Fn->addFnAttr(
|
|
"xray-instruction-threshold",
|
|
llvm::itostr(CGM.getCodeGenOpts().XRayInstructionThreshold));
|
|
}
|
|
|
|
if (ShouldXRayInstrumentFunction()) {
|
|
if (CGM.getCodeGenOpts().XRayIgnoreLoops)
|
|
Fn->addFnAttr("xray-ignore-loops");
|
|
|
|
if (!CGM.getCodeGenOpts().XRayInstrumentationBundle.has(
|
|
XRayInstrKind::FunctionExit))
|
|
Fn->addFnAttr("xray-skip-exit");
|
|
|
|
if (!CGM.getCodeGenOpts().XRayInstrumentationBundle.has(
|
|
XRayInstrKind::FunctionEntry))
|
|
Fn->addFnAttr("xray-skip-entry");
|
|
|
|
auto FuncGroups = CGM.getCodeGenOpts().XRayTotalFunctionGroups;
|
|
if (FuncGroups > 1) {
|
|
auto FuncName = llvm::makeArrayRef<uint8_t>(
|
|
CurFn->getName().bytes_begin(), CurFn->getName().bytes_end());
|
|
auto Group = crc32(FuncName) % FuncGroups;
|
|
if (Group != CGM.getCodeGenOpts().XRaySelectedFunctionGroup &&
|
|
!AlwaysXRayAttr)
|
|
Fn->addFnAttr("function-instrument", "xray-never");
|
|
}
|
|
}
|
|
|
|
if (CGM.getCodeGenOpts().getProfileInstr() != CodeGenOptions::ProfileNone)
|
|
if (CGM.isProfileInstrExcluded(Fn, Loc))
|
|
Fn->addFnAttr(llvm::Attribute::NoProfile);
|
|
|
|
unsigned Count, Offset;
|
|
if (const auto *Attr =
|
|
D ? D->getAttr<PatchableFunctionEntryAttr>() : nullptr) {
|
|
Count = Attr->getCount();
|
|
Offset = Attr->getOffset();
|
|
} else {
|
|
Count = CGM.getCodeGenOpts().PatchableFunctionEntryCount;
|
|
Offset = CGM.getCodeGenOpts().PatchableFunctionEntryOffset;
|
|
}
|
|
if (Count && Offset <= Count) {
|
|
Fn->addFnAttr("patchable-function-entry", std::to_string(Count - Offset));
|
|
if (Offset)
|
|
Fn->addFnAttr("patchable-function-prefix", std::to_string(Offset));
|
|
}
|
|
// Instruct that functions for COFF/CodeView targets should start with a
|
|
// patchable instruction, but only on x86/x64. Don't forward this to ARM/ARM64
|
|
// backends as they don't need it -- instructions on these architectures are
|
|
// always atomically patchable at runtime.
|
|
if (CGM.getCodeGenOpts().HotPatch &&
|
|
getContext().getTargetInfo().getTriple().isX86())
|
|
Fn->addFnAttr("patchable-function", "prologue-short-redirect");
|
|
|
|
// Add no-jump-tables value.
|
|
if (CGM.getCodeGenOpts().NoUseJumpTables)
|
|
Fn->addFnAttr("no-jump-tables", "true");
|
|
|
|
// Add no-inline-line-tables value.
|
|
if (CGM.getCodeGenOpts().NoInlineLineTables)
|
|
Fn->addFnAttr("no-inline-line-tables");
|
|
|
|
// Add profile-sample-accurate value.
|
|
if (CGM.getCodeGenOpts().ProfileSampleAccurate)
|
|
Fn->addFnAttr("profile-sample-accurate");
|
|
|
|
if (!CGM.getCodeGenOpts().SampleProfileFile.empty())
|
|
Fn->addFnAttr("use-sample-profile");
|
|
|
|
if (D && D->hasAttr<CFICanonicalJumpTableAttr>())
|
|
Fn->addFnAttr("cfi-canonical-jump-table");
|
|
|
|
if (D && D->hasAttr<NoProfileFunctionAttr>())
|
|
Fn->addFnAttr(llvm::Attribute::NoProfile);
|
|
|
|
if (FD && getLangOpts().OpenCL) {
|
|
// Add metadata for a kernel function.
|
|
EmitOpenCLKernelMetadata(FD, Fn);
|
|
}
|
|
|
|
// If we are checking function types, emit a function type signature as
|
|
// prologue data.
|
|
if (FD && getLangOpts().CPlusPlus && SanOpts.has(SanitizerKind::Function)) {
|
|
if (llvm::Constant *PrologueSig = getPrologueSignature(CGM, FD)) {
|
|
// Remove any (C++17) exception specifications, to allow calling e.g. a
|
|
// noexcept function through a non-noexcept pointer.
|
|
auto ProtoTy = getContext().getFunctionTypeWithExceptionSpec(
|
|
FD->getType(), EST_None);
|
|
llvm::Constant *FTRTTIConst =
|
|
CGM.GetAddrOfRTTIDescriptor(ProtoTy, /*ForEH=*/true);
|
|
llvm::Constant *FTRTTIConstEncoded =
|
|
EncodeAddrForUseInPrologue(Fn, FTRTTIConst);
|
|
llvm::Constant *PrologueStructElems[] = {PrologueSig, FTRTTIConstEncoded};
|
|
llvm::Constant *PrologueStructConst =
|
|
llvm::ConstantStruct::getAnon(PrologueStructElems, /*Packed=*/true);
|
|
Fn->setPrologueData(PrologueStructConst);
|
|
}
|
|
}
|
|
|
|
// If we're checking nullability, we need to know whether we can check the
|
|
// return value. Initialize the flag to 'true' and refine it in EmitParmDecl.
|
|
if (SanOpts.has(SanitizerKind::NullabilityReturn)) {
|
|
auto Nullability = FnRetTy->getNullability(getContext());
|
|
if (Nullability && *Nullability == NullabilityKind::NonNull) {
|
|
if (!(SanOpts.has(SanitizerKind::ReturnsNonnullAttribute) &&
|
|
CurCodeDecl && CurCodeDecl->getAttr<ReturnsNonNullAttr>()))
|
|
RetValNullabilityPrecondition =
|
|
llvm::ConstantInt::getTrue(getLLVMContext());
|
|
}
|
|
}
|
|
|
|
// If we're in C++ mode and the function name is "main", it is guaranteed
|
|
// to be norecurse by the standard (3.6.1.3 "The function main shall not be
|
|
// used within a program").
|
|
//
|
|
// OpenCL C 2.0 v2.2-11 s6.9.i:
|
|
// Recursion is not supported.
|
|
//
|
|
// SYCL v1.2.1 s3.10:
|
|
// kernels cannot include RTTI information, exception classes,
|
|
// recursive code, virtual functions or make use of C++ libraries that
|
|
// are not compiled for the device.
|
|
if (FD && ((getLangOpts().CPlusPlus && FD->isMain()) ||
|
|
getLangOpts().OpenCL || getLangOpts().SYCLIsDevice ||
|
|
(getLangOpts().CUDA && FD->hasAttr<CUDAGlobalAttr>())))
|
|
Fn->addFnAttr(llvm::Attribute::NoRecurse);
|
|
|
|
llvm::RoundingMode RM = getLangOpts().getFPRoundingMode();
|
|
llvm::fp::ExceptionBehavior FPExceptionBehavior =
|
|
ToConstrainedExceptMD(getLangOpts().getFPExceptionMode());
|
|
Builder.setDefaultConstrainedRounding(RM);
|
|
Builder.setDefaultConstrainedExcept(FPExceptionBehavior);
|
|
if ((FD && (FD->UsesFPIntrin() || FD->hasAttr<StrictFPAttr>())) ||
|
|
(!FD && (FPExceptionBehavior != llvm::fp::ebIgnore ||
|
|
RM != llvm::RoundingMode::NearestTiesToEven))) {
|
|
Builder.setIsFPConstrained(true);
|
|
Fn->addFnAttr(llvm::Attribute::StrictFP);
|
|
}
|
|
|
|
// If a custom alignment is used, force realigning to this alignment on
|
|
// any main function which certainly will need it.
|
|
if (FD && ((FD->isMain() || FD->isMSVCRTEntryPoint()) &&
|
|
CGM.getCodeGenOpts().StackAlignment))
|
|
Fn->addFnAttr("stackrealign");
|
|
|
|
// "main" doesn't need to zero out call-used registers.
|
|
if (FD && FD->isMain())
|
|
Fn->removeFnAttr("zero-call-used-regs");
|
|
|
|
llvm::BasicBlock *EntryBB = createBasicBlock("entry", CurFn);
|
|
|
|
// Create a marker to make it easy to insert allocas into the entryblock
|
|
// later. Don't create this with the builder, because we don't want it
|
|
// folded.
|
|
llvm::Value *Undef = llvm::UndefValue::get(Int32Ty);
|
|
AllocaInsertPt = new llvm::BitCastInst(Undef, Int32Ty, "allocapt", EntryBB);
|
|
|
|
ReturnBlock = getJumpDestInCurrentScope("return");
|
|
|
|
Builder.SetInsertPoint(EntryBB);
|
|
|
|
// If we're checking the return value, allocate space for a pointer to a
|
|
// precise source location of the checked return statement.
|
|
if (requiresReturnValueCheck()) {
|
|
ReturnLocation = CreateDefaultAlignTempAlloca(Int8PtrTy, "return.sloc.ptr");
|
|
Builder.CreateStore(llvm::ConstantPointerNull::get(Int8PtrTy),
|
|
ReturnLocation);
|
|
}
|
|
|
|
// Emit subprogram debug descriptor.
|
|
if (CGDebugInfo *DI = getDebugInfo()) {
|
|
// Reconstruct the type from the argument list so that implicit parameters,
|
|
// such as 'this' and 'vtt', show up in the debug info. Preserve the calling
|
|
// convention.
|
|
DI->emitFunctionStart(GD, Loc, StartLoc,
|
|
DI->getFunctionType(FD, RetTy, Args), CurFn,
|
|
CurFuncIsThunk);
|
|
}
|
|
|
|
if (ShouldInstrumentFunction()) {
|
|
if (CGM.getCodeGenOpts().InstrumentFunctions)
|
|
CurFn->addFnAttr("instrument-function-entry", "__cyg_profile_func_enter");
|
|
if (CGM.getCodeGenOpts().InstrumentFunctionsAfterInlining)
|
|
CurFn->addFnAttr("instrument-function-entry-inlined",
|
|
"__cyg_profile_func_enter");
|
|
if (CGM.getCodeGenOpts().InstrumentFunctionEntryBare)
|
|
CurFn->addFnAttr("instrument-function-entry-inlined",
|
|
"__cyg_profile_func_enter_bare");
|
|
}
|
|
|
|
// Since emitting the mcount call here impacts optimizations such as function
|
|
// inlining, we just add an attribute to insert a mcount call in backend.
|
|
// The attribute "counting-function" is set to mcount function name which is
|
|
// architecture dependent.
|
|
if (CGM.getCodeGenOpts().InstrumentForProfiling) {
|
|
// Calls to fentry/mcount should not be generated if function has
|
|
// the no_instrument_function attribute.
|
|
if (!CurFuncDecl || !CurFuncDecl->hasAttr<NoInstrumentFunctionAttr>()) {
|
|
if (CGM.getCodeGenOpts().CallFEntry)
|
|
Fn->addFnAttr("fentry-call", "true");
|
|
else {
|
|
Fn->addFnAttr("instrument-function-entry-inlined",
|
|
getTarget().getMCountName());
|
|
}
|
|
if (CGM.getCodeGenOpts().MNopMCount) {
|
|
if (!CGM.getCodeGenOpts().CallFEntry)
|
|
CGM.getDiags().Report(diag::err_opt_not_valid_without_opt)
|
|
<< "-mnop-mcount" << "-mfentry";
|
|
Fn->addFnAttr("mnop-mcount");
|
|
}
|
|
|
|
if (CGM.getCodeGenOpts().RecordMCount) {
|
|
if (!CGM.getCodeGenOpts().CallFEntry)
|
|
CGM.getDiags().Report(diag::err_opt_not_valid_without_opt)
|
|
<< "-mrecord-mcount" << "-mfentry";
|
|
Fn->addFnAttr("mrecord-mcount");
|
|
}
|
|
}
|
|
}
|
|
|
|
if (CGM.getCodeGenOpts().PackedStack) {
|
|
if (getContext().getTargetInfo().getTriple().getArch() !=
|
|
llvm::Triple::systemz)
|
|
CGM.getDiags().Report(diag::err_opt_not_valid_on_target)
|
|
<< "-mpacked-stack";
|
|
Fn->addFnAttr("packed-stack");
|
|
}
|
|
|
|
if (CGM.getCodeGenOpts().WarnStackSize != UINT_MAX &&
|
|
!CGM.getDiags().isIgnored(diag::warn_fe_backend_frame_larger_than, Loc))
|
|
Fn->addFnAttr("warn-stack-size",
|
|
std::to_string(CGM.getCodeGenOpts().WarnStackSize));
|
|
|
|
if (RetTy->isVoidType()) {
|
|
// Void type; nothing to return.
|
|
ReturnValue = Address::invalid();
|
|
|
|
// Count the implicit return.
|
|
if (!endsWithReturn(D))
|
|
++NumReturnExprs;
|
|
} else if (CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::Indirect) {
|
|
// Indirect return; emit returned value directly into sret slot.
|
|
// This reduces code size, and affects correctness in C++.
|
|
auto AI = CurFn->arg_begin();
|
|
if (CurFnInfo->getReturnInfo().isSRetAfterThis())
|
|
++AI;
|
|
ReturnValue = Address(&*AI, ConvertType(RetTy),
|
|
CurFnInfo->getReturnInfo().getIndirectAlign());
|
|
if (!CurFnInfo->getReturnInfo().getIndirectByVal()) {
|
|
ReturnValuePointer =
|
|
CreateDefaultAlignTempAlloca(Int8PtrTy, "result.ptr");
|
|
Builder.CreateStore(Builder.CreatePointerBitCastOrAddrSpaceCast(
|
|
ReturnValue.getPointer(), Int8PtrTy),
|
|
ReturnValuePointer);
|
|
}
|
|
} else if (CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::InAlloca &&
|
|
!hasScalarEvaluationKind(CurFnInfo->getReturnType())) {
|
|
// Load the sret pointer from the argument struct and return into that.
|
|
unsigned Idx = CurFnInfo->getReturnInfo().getInAllocaFieldIndex();
|
|
llvm::Function::arg_iterator EI = CurFn->arg_end();
|
|
--EI;
|
|
llvm::Value *Addr = Builder.CreateStructGEP(
|
|
EI->getType()->getPointerElementType(), &*EI, Idx);
|
|
llvm::Type *Ty =
|
|
cast<llvm::GetElementPtrInst>(Addr)->getResultElementType();
|
|
ReturnValuePointer = Address(Addr, getPointerAlign());
|
|
Addr = Builder.CreateAlignedLoad(Ty, Addr, getPointerAlign(), "agg.result");
|
|
ReturnValue = Address(Addr, CGM.getNaturalTypeAlignment(RetTy));
|
|
} else {
|
|
ReturnValue = CreateIRTemp(RetTy, "retval");
|
|
|
|
// Tell the epilog emitter to autorelease the result. We do this
|
|
// now so that various specialized functions can suppress it
|
|
// during their IR-generation.
|
|
if (getLangOpts().ObjCAutoRefCount &&
|
|
!CurFnInfo->isReturnsRetained() &&
|
|
RetTy->isObjCRetainableType())
|
|
AutoreleaseResult = true;
|
|
}
|
|
|
|
EmitStartEHSpec(CurCodeDecl);
|
|
|
|
PrologueCleanupDepth = EHStack.stable_begin();
|
|
|
|
// Emit OpenMP specific initialization of the device functions.
|
|
if (getLangOpts().OpenMP && CurCodeDecl)
|
|
CGM.getOpenMPRuntime().emitFunctionProlog(*this, CurCodeDecl);
|
|
|
|
EmitFunctionProlog(*CurFnInfo, CurFn, Args);
|
|
|
|
if (D && isa<CXXMethodDecl>(D) && cast<CXXMethodDecl>(D)->isInstance()) {
|
|
CGM.getCXXABI().EmitInstanceFunctionProlog(*this);
|
|
const CXXMethodDecl *MD = cast<CXXMethodDecl>(D);
|
|
if (MD->getParent()->isLambda() &&
|
|
MD->getOverloadedOperator() == OO_Call) {
|
|
// We're in a lambda; figure out the captures.
|
|
MD->getParent()->getCaptureFields(LambdaCaptureFields,
|
|
LambdaThisCaptureField);
|
|
if (LambdaThisCaptureField) {
|
|
// If the lambda captures the object referred to by '*this' - either by
|
|
// value or by reference, make sure CXXThisValue points to the correct
|
|
// object.
|
|
|
|
// Get the lvalue for the field (which is a copy of the enclosing object
|
|
// or contains the address of the enclosing object).
|
|
LValue ThisFieldLValue = EmitLValueForLambdaField(LambdaThisCaptureField);
|
|
if (!LambdaThisCaptureField->getType()->isPointerType()) {
|
|
// If the enclosing object was captured by value, just use its address.
|
|
CXXThisValue = ThisFieldLValue.getAddress(*this).getPointer();
|
|
} else {
|
|
// Load the lvalue pointed to by the field, since '*this' was captured
|
|
// by reference.
|
|
CXXThisValue =
|
|
EmitLoadOfLValue(ThisFieldLValue, SourceLocation()).getScalarVal();
|
|
}
|
|
}
|
|
for (auto *FD : MD->getParent()->fields()) {
|
|
if (FD->hasCapturedVLAType()) {
|
|
auto *ExprArg = EmitLoadOfLValue(EmitLValueForLambdaField(FD),
|
|
SourceLocation()).getScalarVal();
|
|
auto VAT = FD->getCapturedVLAType();
|
|
VLASizeMap[VAT->getSizeExpr()] = ExprArg;
|
|
}
|
|
}
|
|
} else {
|
|
// Not in a lambda; just use 'this' from the method.
|
|
// FIXME: Should we generate a new load for each use of 'this'? The
|
|
// fast register allocator would be happier...
|
|
CXXThisValue = CXXABIThisValue;
|
|
}
|
|
|
|
// Check the 'this' pointer once per function, if it's available.
|
|
if (CXXABIThisValue) {
|
|
SanitizerSet SkippedChecks;
|
|
SkippedChecks.set(SanitizerKind::ObjectSize, true);
|
|
QualType ThisTy = MD->getThisType();
|
|
|
|
// If this is the call operator of a lambda with no capture-default, it
|
|
// may have a static invoker function, which may call this operator with
|
|
// a null 'this' pointer.
|
|
if (isLambdaCallOperator(MD) &&
|
|
MD->getParent()->getLambdaCaptureDefault() == LCD_None)
|
|
SkippedChecks.set(SanitizerKind::Null, true);
|
|
|
|
EmitTypeCheck(
|
|
isa<CXXConstructorDecl>(MD) ? TCK_ConstructorCall : TCK_MemberCall,
|
|
Loc, CXXABIThisValue, ThisTy, CXXABIThisAlignment, SkippedChecks);
|
|
}
|
|
}
|
|
|
|
// If any of the arguments have a variably modified type, make sure to
|
|
// emit the type size.
|
|
for (FunctionArgList::const_iterator i = Args.begin(), e = Args.end();
|
|
i != e; ++i) {
|
|
const VarDecl *VD = *i;
|
|
|
|
// Dig out the type as written from ParmVarDecls; it's unclear whether
|
|
// the standard (C99 6.9.1p10) requires this, but we're following the
|
|
// precedent set by gcc.
|
|
QualType Ty;
|
|
if (const ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(VD))
|
|
Ty = PVD->getOriginalType();
|
|
else
|
|
Ty = VD->getType();
|
|
|
|
if (Ty->isVariablyModifiedType())
|
|
EmitVariablyModifiedType(Ty);
|
|
}
|
|
// Emit a location at the end of the prologue.
|
|
if (CGDebugInfo *DI = getDebugInfo())
|
|
DI->EmitLocation(Builder, StartLoc);
|
|
|
|
// TODO: Do we need to handle this in two places like we do with
|
|
// target-features/target-cpu?
|
|
if (CurFuncDecl)
|
|
if (const auto *VecWidth = CurFuncDecl->getAttr<MinVectorWidthAttr>())
|
|
LargestVectorWidth = VecWidth->getVectorWidth();
|
|
}
|
|
|
|
void CodeGenFunction::EmitFunctionBody(const Stmt *Body) {
|
|
incrementProfileCounter(Body);
|
|
if (const CompoundStmt *S = dyn_cast<CompoundStmt>(Body))
|
|
EmitCompoundStmtWithoutScope(*S);
|
|
else
|
|
EmitStmt(Body);
|
|
|
|
// This is checked after emitting the function body so we know if there
|
|
// are any permitted infinite loops.
|
|
if (checkIfFunctionMustProgress())
|
|
CurFn->addFnAttr(llvm::Attribute::MustProgress);
|
|
}
|
|
|
|
/// When instrumenting to collect profile data, the counts for some blocks
|
|
/// such as switch cases need to not include the fall-through counts, so
|
|
/// emit a branch around the instrumentation code. When not instrumenting,
|
|
/// this just calls EmitBlock().
|
|
void CodeGenFunction::EmitBlockWithFallThrough(llvm::BasicBlock *BB,
|
|
const Stmt *S) {
|
|
llvm::BasicBlock *SkipCountBB = nullptr;
|
|
if (HaveInsertPoint() && CGM.getCodeGenOpts().hasProfileClangInstr()) {
|
|
// When instrumenting for profiling, the fallthrough to certain
|
|
// statements needs to skip over the instrumentation code so that we
|
|
// get an accurate count.
|
|
SkipCountBB = createBasicBlock("skipcount");
|
|
EmitBranch(SkipCountBB);
|
|
}
|
|
EmitBlock(BB);
|
|
uint64_t CurrentCount = getCurrentProfileCount();
|
|
incrementProfileCounter(S);
|
|
setCurrentProfileCount(getCurrentProfileCount() + CurrentCount);
|
|
if (SkipCountBB)
|
|
EmitBlock(SkipCountBB);
|
|
}
|
|
|
|
/// Tries to mark the given function nounwind based on the
|
|
/// non-existence of any throwing calls within it. We believe this is
|
|
/// lightweight enough to do at -O0.
|
|
static void TryMarkNoThrow(llvm::Function *F) {
|
|
// LLVM treats 'nounwind' on a function as part of the type, so we
|
|
// can't do this on functions that can be overwritten.
|
|
if (F->isInterposable()) return;
|
|
|
|
for (llvm::BasicBlock &BB : *F)
|
|
for (llvm::Instruction &I : BB)
|
|
if (I.mayThrow())
|
|
return;
|
|
|
|
F->setDoesNotThrow();
|
|
}
|
|
|
|
QualType CodeGenFunction::BuildFunctionArgList(GlobalDecl GD,
|
|
FunctionArgList &Args) {
|
|
const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
|
|
QualType ResTy = FD->getReturnType();
|
|
|
|
const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD);
|
|
if (MD && MD->isInstance()) {
|
|
if (CGM.getCXXABI().HasThisReturn(GD))
|
|
ResTy = MD->getThisType();
|
|
else if (CGM.getCXXABI().hasMostDerivedReturn(GD))
|
|
ResTy = CGM.getContext().VoidPtrTy;
|
|
CGM.getCXXABI().buildThisParam(*this, Args);
|
|
}
|
|
|
|
// The base version of an inheriting constructor whose constructed base is a
|
|
// virtual base is not passed any arguments (because it doesn't actually call
|
|
// the inherited constructor).
|
|
bool PassedParams = true;
|
|
if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD))
|
|
if (auto Inherited = CD->getInheritedConstructor())
|
|
PassedParams =
|
|
getTypes().inheritingCtorHasParams(Inherited, GD.getCtorType());
|
|
|
|
if (PassedParams) {
|
|
for (auto *Param : FD->parameters()) {
|
|
Args.push_back(Param);
|
|
if (!Param->hasAttr<PassObjectSizeAttr>())
|
|
continue;
|
|
|
|
auto *Implicit = ImplicitParamDecl::Create(
|
|
getContext(), Param->getDeclContext(), Param->getLocation(),
|
|
/*Id=*/nullptr, getContext().getSizeType(), ImplicitParamDecl::Other);
|
|
SizeArguments[Param] = Implicit;
|
|
Args.push_back(Implicit);
|
|
}
|
|
}
|
|
|
|
if (MD && (isa<CXXConstructorDecl>(MD) || isa<CXXDestructorDecl>(MD)))
|
|
CGM.getCXXABI().addImplicitStructorParams(*this, ResTy, Args);
|
|
|
|
return ResTy;
|
|
}
|
|
|
|
void CodeGenFunction::GenerateCode(GlobalDecl GD, llvm::Function *Fn,
|
|
const CGFunctionInfo &FnInfo) {
|
|
assert(Fn && "generating code for null Function");
|
|
const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
|
|
CurGD = GD;
|
|
|
|
FunctionArgList Args;
|
|
QualType ResTy = BuildFunctionArgList(GD, Args);
|
|
|
|
if (FD->isInlineBuiltinDeclaration()) {
|
|
// When generating code for a builtin with an inline declaration, use a
|
|
// mangled name to hold the actual body, while keeping an external
|
|
// definition in case the function pointer is referenced somewhere.
|
|
std::string FDInlineName = (Fn->getName() + ".inline").str();
|
|
llvm::Module *M = Fn->getParent();
|
|
llvm::Function *Clone = M->getFunction(FDInlineName);
|
|
if (!Clone) {
|
|
Clone = llvm::Function::Create(Fn->getFunctionType(),
|
|
llvm::GlobalValue::InternalLinkage,
|
|
Fn->getAddressSpace(), FDInlineName, M);
|
|
Clone->addFnAttr(llvm::Attribute::AlwaysInline);
|
|
}
|
|
Fn->setLinkage(llvm::GlobalValue::ExternalLinkage);
|
|
Fn = Clone;
|
|
} else {
|
|
// Detect the unusual situation where an inline version is shadowed by a
|
|
// non-inline version. In that case we should pick the external one
|
|
// everywhere. That's GCC behavior too. Unfortunately, I cannot find a way
|
|
// to detect that situation before we reach codegen, so do some late
|
|
// replacement.
|
|
for (const FunctionDecl *PD = FD->getPreviousDecl(); PD;
|
|
PD = PD->getPreviousDecl()) {
|
|
if (LLVM_UNLIKELY(PD->isInlineBuiltinDeclaration())) {
|
|
std::string FDInlineName = (Fn->getName() + ".inline").str();
|
|
llvm::Module *M = Fn->getParent();
|
|
if (llvm::Function *Clone = M->getFunction(FDInlineName)) {
|
|
Clone->replaceAllUsesWith(Fn);
|
|
Clone->eraseFromParent();
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Check if we should generate debug info for this function.
|
|
if (FD->hasAttr<NoDebugAttr>()) {
|
|
// Clear non-distinct debug info that was possibly attached to the function
|
|
// due to an earlier declaration without the nodebug attribute
|
|
Fn->setSubprogram(nullptr);
|
|
// Disable debug info indefinitely for this function
|
|
DebugInfo = nullptr;
|
|
}
|
|
|
|
// The function might not have a body if we're generating thunks for a
|
|
// function declaration.
|
|
SourceRange BodyRange;
|
|
if (Stmt *Body = FD->getBody())
|
|
BodyRange = Body->getSourceRange();
|
|
else
|
|
BodyRange = FD->getLocation();
|
|
CurEHLocation = BodyRange.getEnd();
|
|
|
|
// Use the location of the start of the function to determine where
|
|
// the function definition is located. By default use the location
|
|
// of the declaration as the location for the subprogram. A function
|
|
// may lack a declaration in the source code if it is created by code
|
|
// gen. (examples: _GLOBAL__I_a, __cxx_global_array_dtor, thunk).
|
|
SourceLocation Loc = FD->getLocation();
|
|
|
|
// If this is a function specialization then use the pattern body
|
|
// as the location for the function.
|
|
if (const FunctionDecl *SpecDecl = FD->getTemplateInstantiationPattern())
|
|
if (SpecDecl->hasBody(SpecDecl))
|
|
Loc = SpecDecl->getLocation();
|
|
|
|
Stmt *Body = FD->getBody();
|
|
|
|
if (Body) {
|
|
// Coroutines always emit lifetime markers.
|
|
if (isa<CoroutineBodyStmt>(Body))
|
|
ShouldEmitLifetimeMarkers = true;
|
|
|
|
// Initialize helper which will detect jumps which can cause invalid
|
|
// lifetime markers.
|
|
if (ShouldEmitLifetimeMarkers)
|
|
Bypasses.Init(Body);
|
|
}
|
|
|
|
// Emit the standard function prologue.
|
|
StartFunction(GD, ResTy, Fn, FnInfo, Args, Loc, BodyRange.getBegin());
|
|
|
|
// Save parameters for coroutine function.
|
|
if (Body && isa_and_nonnull<CoroutineBodyStmt>(Body))
|
|
for (const auto *ParamDecl : FD->parameters())
|
|
FnArgs.push_back(ParamDecl);
|
|
|
|
// Generate the body of the function.
|
|
PGO.assignRegionCounters(GD, CurFn);
|
|
if (isa<CXXDestructorDecl>(FD))
|
|
EmitDestructorBody(Args);
|
|
else if (isa<CXXConstructorDecl>(FD))
|
|
EmitConstructorBody(Args);
|
|
else if (getLangOpts().CUDA &&
|
|
!getLangOpts().CUDAIsDevice &&
|
|
FD->hasAttr<CUDAGlobalAttr>())
|
|
CGM.getCUDARuntime().emitDeviceStub(*this, Args);
|
|
else if (isa<CXXMethodDecl>(FD) &&
|
|
cast<CXXMethodDecl>(FD)->isLambdaStaticInvoker()) {
|
|
// The lambda static invoker function is special, because it forwards or
|
|
// clones the body of the function call operator (but is actually static).
|
|
EmitLambdaStaticInvokeBody(cast<CXXMethodDecl>(FD));
|
|
} else if (FD->isDefaulted() && isa<CXXMethodDecl>(FD) &&
|
|
(cast<CXXMethodDecl>(FD)->isCopyAssignmentOperator() ||
|
|
cast<CXXMethodDecl>(FD)->isMoveAssignmentOperator())) {
|
|
// Implicit copy-assignment gets the same special treatment as implicit
|
|
// copy-constructors.
|
|
emitImplicitAssignmentOperatorBody(Args);
|
|
} else if (Body) {
|
|
EmitFunctionBody(Body);
|
|
} else
|
|
llvm_unreachable("no definition for emitted function");
|
|
|
|
// C++11 [stmt.return]p2:
|
|
// Flowing off the end of a function [...] results in undefined behavior in
|
|
// a value-returning function.
|
|
// C11 6.9.1p12:
|
|
// If the '}' that terminates a function is reached, and the value of the
|
|
// function call is used by the caller, the behavior is undefined.
|
|
if (getLangOpts().CPlusPlus && !FD->hasImplicitReturnZero() && !SawAsmBlock &&
|
|
!FD->getReturnType()->isVoidType() && Builder.GetInsertBlock()) {
|
|
bool ShouldEmitUnreachable =
|
|
CGM.getCodeGenOpts().StrictReturn ||
|
|
!CGM.MayDropFunctionReturn(FD->getASTContext(), FD->getReturnType());
|
|
if (SanOpts.has(SanitizerKind::Return)) {
|
|
SanitizerScope SanScope(this);
|
|
llvm::Value *IsFalse = Builder.getFalse();
|
|
EmitCheck(std::make_pair(IsFalse, SanitizerKind::Return),
|
|
SanitizerHandler::MissingReturn,
|
|
EmitCheckSourceLocation(FD->getLocation()), None);
|
|
} else if (ShouldEmitUnreachable) {
|
|
if (CGM.getCodeGenOpts().OptimizationLevel == 0)
|
|
EmitTrapCall(llvm::Intrinsic::trap);
|
|
}
|
|
if (SanOpts.has(SanitizerKind::Return) || ShouldEmitUnreachable) {
|
|
Builder.CreateUnreachable();
|
|
Builder.ClearInsertionPoint();
|
|
}
|
|
}
|
|
|
|
// Emit the standard function epilogue.
|
|
FinishFunction(BodyRange.getEnd());
|
|
|
|
// If we haven't marked the function nothrow through other means, do
|
|
// a quick pass now to see if we can.
|
|
if (!CurFn->doesNotThrow())
|
|
TryMarkNoThrow(CurFn);
|
|
}
|
|
|
|
/// ContainsLabel - Return true if the statement contains a label in it. If
|
|
/// this statement is not executed normally, it not containing a label means
|
|
/// that we can just remove the code.
|
|
bool CodeGenFunction::ContainsLabel(const Stmt *S, bool IgnoreCaseStmts) {
|
|
// Null statement, not a label!
|
|
if (!S) return false;
|
|
|
|
// If this is a label, we have to emit the code, consider something like:
|
|
// if (0) { ... foo: bar(); } goto foo;
|
|
//
|
|
// TODO: If anyone cared, we could track __label__'s, since we know that you
|
|
// can't jump to one from outside their declared region.
|
|
if (isa<LabelStmt>(S))
|
|
return true;
|
|
|
|
// If this is a case/default statement, and we haven't seen a switch, we have
|
|
// to emit the code.
|
|
if (isa<SwitchCase>(S) && !IgnoreCaseStmts)
|
|
return true;
|
|
|
|
// If this is a switch statement, we want to ignore cases below it.
|
|
if (isa<SwitchStmt>(S))
|
|
IgnoreCaseStmts = true;
|
|
|
|
// Scan subexpressions for verboten labels.
|
|
for (const Stmt *SubStmt : S->children())
|
|
if (ContainsLabel(SubStmt, IgnoreCaseStmts))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
/// containsBreak - Return true if the statement contains a break out of it.
|
|
/// If the statement (recursively) contains a switch or loop with a break
|
|
/// inside of it, this is fine.
|
|
bool CodeGenFunction::containsBreak(const Stmt *S) {
|
|
// Null statement, not a label!
|
|
if (!S) return false;
|
|
|
|
// If this is a switch or loop that defines its own break scope, then we can
|
|
// include it and anything inside of it.
|
|
if (isa<SwitchStmt>(S) || isa<WhileStmt>(S) || isa<DoStmt>(S) ||
|
|
isa<ForStmt>(S))
|
|
return false;
|
|
|
|
if (isa<BreakStmt>(S))
|
|
return true;
|
|
|
|
// Scan subexpressions for verboten breaks.
|
|
for (const Stmt *SubStmt : S->children())
|
|
if (containsBreak(SubStmt))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
bool CodeGenFunction::mightAddDeclToScope(const Stmt *S) {
|
|
if (!S) return false;
|
|
|
|
// Some statement kinds add a scope and thus never add a decl to the current
|
|
// scope. Note, this list is longer than the list of statements that might
|
|
// have an unscoped decl nested within them, but this way is conservatively
|
|
// correct even if more statement kinds are added.
|
|
if (isa<IfStmt>(S) || isa<SwitchStmt>(S) || isa<WhileStmt>(S) ||
|
|
isa<DoStmt>(S) || isa<ForStmt>(S) || isa<CompoundStmt>(S) ||
|
|
isa<CXXForRangeStmt>(S) || isa<CXXTryStmt>(S) ||
|
|
isa<ObjCForCollectionStmt>(S) || isa<ObjCAtTryStmt>(S))
|
|
return false;
|
|
|
|
if (isa<DeclStmt>(S))
|
|
return true;
|
|
|
|
for (const Stmt *SubStmt : S->children())
|
|
if (mightAddDeclToScope(SubStmt))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
/// ConstantFoldsToSimpleInteger - If the specified expression does not fold
|
|
/// to a constant, or if it does but contains a label, return false. If it
|
|
/// constant folds return true and set the boolean result in Result.
|
|
bool CodeGenFunction::ConstantFoldsToSimpleInteger(const Expr *Cond,
|
|
bool &ResultBool,
|
|
bool AllowLabels) {
|
|
llvm::APSInt ResultInt;
|
|
if (!ConstantFoldsToSimpleInteger(Cond, ResultInt, AllowLabels))
|
|
return false;
|
|
|
|
ResultBool = ResultInt.getBoolValue();
|
|
return true;
|
|
}
|
|
|
|
/// ConstantFoldsToSimpleInteger - If the specified expression does not fold
|
|
/// to a constant, or if it does but contains a label, return false. If it
|
|
/// constant folds return true and set the folded value.
|
|
bool CodeGenFunction::ConstantFoldsToSimpleInteger(const Expr *Cond,
|
|
llvm::APSInt &ResultInt,
|
|
bool AllowLabels) {
|
|
// FIXME: Rename and handle conversion of other evaluatable things
|
|
// to bool.
|
|
Expr::EvalResult Result;
|
|
if (!Cond->EvaluateAsInt(Result, getContext()))
|
|
return false; // Not foldable, not integer or not fully evaluatable.
|
|
|
|
llvm::APSInt Int = Result.Val.getInt();
|
|
if (!AllowLabels && CodeGenFunction::ContainsLabel(Cond))
|
|
return false; // Contains a label.
|
|
|
|
ResultInt = Int;
|
|
return true;
|
|
}
|
|
|
|
/// Determine whether the given condition is an instrumentable condition
|
|
/// (i.e. no "&&" or "||").
|
|
bool CodeGenFunction::isInstrumentedCondition(const Expr *C) {
|
|
// Bypass simplistic logical-NOT operator before determining whether the
|
|
// condition contains any other logical operator.
|
|
if (const UnaryOperator *UnOp = dyn_cast<UnaryOperator>(C->IgnoreParens()))
|
|
if (UnOp->getOpcode() == UO_LNot)
|
|
C = UnOp->getSubExpr();
|
|
|
|
const BinaryOperator *BOp = dyn_cast<BinaryOperator>(C->IgnoreParens());
|
|
return (!BOp || !BOp->isLogicalOp());
|
|
}
|
|
|
|
/// EmitBranchToCounterBlock - Emit a conditional branch to a new block that
|
|
/// increments a profile counter based on the semantics of the given logical
|
|
/// operator opcode. This is used to instrument branch condition coverage for
|
|
/// logical operators.
|
|
void CodeGenFunction::EmitBranchToCounterBlock(
|
|
const Expr *Cond, BinaryOperator::Opcode LOp, llvm::BasicBlock *TrueBlock,
|
|
llvm::BasicBlock *FalseBlock, uint64_t TrueCount /* = 0 */,
|
|
Stmt::Likelihood LH /* =None */, const Expr *CntrIdx /* = nullptr */) {
|
|
// If not instrumenting, just emit a branch.
|
|
bool InstrumentRegions = CGM.getCodeGenOpts().hasProfileClangInstr();
|
|
if (!InstrumentRegions || !isInstrumentedCondition(Cond))
|
|
return EmitBranchOnBoolExpr(Cond, TrueBlock, FalseBlock, TrueCount, LH);
|
|
|
|
llvm::BasicBlock *ThenBlock = nullptr;
|
|
llvm::BasicBlock *ElseBlock = nullptr;
|
|
llvm::BasicBlock *NextBlock = nullptr;
|
|
|
|
// Create the block we'll use to increment the appropriate counter.
|
|
llvm::BasicBlock *CounterIncrBlock = createBasicBlock("lop.rhscnt");
|
|
|
|
// Set block pointers according to Logical-AND (BO_LAnd) semantics. This
|
|
// means we need to evaluate the condition and increment the counter on TRUE:
|
|
//
|
|
// if (Cond)
|
|
// goto CounterIncrBlock;
|
|
// else
|
|
// goto FalseBlock;
|
|
//
|
|
// CounterIncrBlock:
|
|
// Counter++;
|
|
// goto TrueBlock;
|
|
|
|
if (LOp == BO_LAnd) {
|
|
ThenBlock = CounterIncrBlock;
|
|
ElseBlock = FalseBlock;
|
|
NextBlock = TrueBlock;
|
|
}
|
|
|
|
// Set block pointers according to Logical-OR (BO_LOr) semantics. This means
|
|
// we need to evaluate the condition and increment the counter on FALSE:
|
|
//
|
|
// if (Cond)
|
|
// goto TrueBlock;
|
|
// else
|
|
// goto CounterIncrBlock;
|
|
//
|
|
// CounterIncrBlock:
|
|
// Counter++;
|
|
// goto FalseBlock;
|
|
|
|
else if (LOp == BO_LOr) {
|
|
ThenBlock = TrueBlock;
|
|
ElseBlock = CounterIncrBlock;
|
|
NextBlock = FalseBlock;
|
|
} else {
|
|
llvm_unreachable("Expected Opcode must be that of a Logical Operator");
|
|
}
|
|
|
|
// Emit Branch based on condition.
|
|
EmitBranchOnBoolExpr(Cond, ThenBlock, ElseBlock, TrueCount, LH);
|
|
|
|
// Emit the block containing the counter increment(s).
|
|
EmitBlock(CounterIncrBlock);
|
|
|
|
// Increment corresponding counter; if index not provided, use Cond as index.
|
|
incrementProfileCounter(CntrIdx ? CntrIdx : Cond);
|
|
|
|
// Go to the next block.
|
|
EmitBranch(NextBlock);
|
|
}
|
|
|
|
/// EmitBranchOnBoolExpr - Emit a branch on a boolean condition (e.g. for an if
|
|
/// statement) to the specified blocks. Based on the condition, this might try
|
|
/// to simplify the codegen of the conditional based on the branch.
|
|
/// \param LH The value of the likelihood attribute on the True branch.
|
|
void CodeGenFunction::EmitBranchOnBoolExpr(const Expr *Cond,
|
|
llvm::BasicBlock *TrueBlock,
|
|
llvm::BasicBlock *FalseBlock,
|
|
uint64_t TrueCount,
|
|
Stmt::Likelihood LH) {
|
|
Cond = Cond->IgnoreParens();
|
|
|
|
if (const BinaryOperator *CondBOp = dyn_cast<BinaryOperator>(Cond)) {
|
|
|
|
// Handle X && Y in a condition.
|
|
if (CondBOp->getOpcode() == BO_LAnd) {
|
|
// If we have "1 && X", simplify the code. "0 && X" would have constant
|
|
// folded if the case was simple enough.
|
|
bool ConstantBool = false;
|
|
if (ConstantFoldsToSimpleInteger(CondBOp->getLHS(), ConstantBool) &&
|
|
ConstantBool) {
|
|
// br(1 && X) -> br(X).
|
|
incrementProfileCounter(CondBOp);
|
|
return EmitBranchToCounterBlock(CondBOp->getRHS(), BO_LAnd, TrueBlock,
|
|
FalseBlock, TrueCount, LH);
|
|
}
|
|
|
|
// If we have "X && 1", simplify the code to use an uncond branch.
|
|
// "X && 0" would have been constant folded to 0.
|
|
if (ConstantFoldsToSimpleInteger(CondBOp->getRHS(), ConstantBool) &&
|
|
ConstantBool) {
|
|
// br(X && 1) -> br(X).
|
|
return EmitBranchToCounterBlock(CondBOp->getLHS(), BO_LAnd, TrueBlock,
|
|
FalseBlock, TrueCount, LH, CondBOp);
|
|
}
|
|
|
|
// Emit the LHS as a conditional. If the LHS conditional is false, we
|
|
// want to jump to the FalseBlock.
|
|
llvm::BasicBlock *LHSTrue = createBasicBlock("land.lhs.true");
|
|
// The counter tells us how often we evaluate RHS, and all of TrueCount
|
|
// can be propagated to that branch.
|
|
uint64_t RHSCount = getProfileCount(CondBOp->getRHS());
|
|
|
|
ConditionalEvaluation eval(*this);
|
|
{
|
|
ApplyDebugLocation DL(*this, Cond);
|
|
// Propagate the likelihood attribute like __builtin_expect
|
|
// __builtin_expect(X && Y, 1) -> X and Y are likely
|
|
// __builtin_expect(X && Y, 0) -> only Y is unlikely
|
|
EmitBranchOnBoolExpr(CondBOp->getLHS(), LHSTrue, FalseBlock, RHSCount,
|
|
LH == Stmt::LH_Unlikely ? Stmt::LH_None : LH);
|
|
EmitBlock(LHSTrue);
|
|
}
|
|
|
|
incrementProfileCounter(CondBOp);
|
|
setCurrentProfileCount(getProfileCount(CondBOp->getRHS()));
|
|
|
|
// Any temporaries created here are conditional.
|
|
eval.begin(*this);
|
|
EmitBranchToCounterBlock(CondBOp->getRHS(), BO_LAnd, TrueBlock,
|
|
FalseBlock, TrueCount, LH);
|
|
eval.end(*this);
|
|
|
|
return;
|
|
}
|
|
|
|
if (CondBOp->getOpcode() == BO_LOr) {
|
|
// If we have "0 || X", simplify the code. "1 || X" would have constant
|
|
// folded if the case was simple enough.
|
|
bool ConstantBool = false;
|
|
if (ConstantFoldsToSimpleInteger(CondBOp->getLHS(), ConstantBool) &&
|
|
!ConstantBool) {
|
|
// br(0 || X) -> br(X).
|
|
incrementProfileCounter(CondBOp);
|
|
return EmitBranchToCounterBlock(CondBOp->getRHS(), BO_LOr, TrueBlock,
|
|
FalseBlock, TrueCount, LH);
|
|
}
|
|
|
|
// If we have "X || 0", simplify the code to use an uncond branch.
|
|
// "X || 1" would have been constant folded to 1.
|
|
if (ConstantFoldsToSimpleInteger(CondBOp->getRHS(), ConstantBool) &&
|
|
!ConstantBool) {
|
|
// br(X || 0) -> br(X).
|
|
return EmitBranchToCounterBlock(CondBOp->getLHS(), BO_LOr, TrueBlock,
|
|
FalseBlock, TrueCount, LH, CondBOp);
|
|
}
|
|
|
|
// Emit the LHS as a conditional. If the LHS conditional is true, we
|
|
// want to jump to the TrueBlock.
|
|
llvm::BasicBlock *LHSFalse = createBasicBlock("lor.lhs.false");
|
|
// We have the count for entry to the RHS and for the whole expression
|
|
// being true, so we can divy up True count between the short circuit and
|
|
// the RHS.
|
|
uint64_t LHSCount =
|
|
getCurrentProfileCount() - getProfileCount(CondBOp->getRHS());
|
|
uint64_t RHSCount = TrueCount - LHSCount;
|
|
|
|
ConditionalEvaluation eval(*this);
|
|
{
|
|
// Propagate the likelihood attribute like __builtin_expect
|
|
// __builtin_expect(X || Y, 1) -> only Y is likely
|
|
// __builtin_expect(X || Y, 0) -> both X and Y are unlikely
|
|
ApplyDebugLocation DL(*this, Cond);
|
|
EmitBranchOnBoolExpr(CondBOp->getLHS(), TrueBlock, LHSFalse, LHSCount,
|
|
LH == Stmt::LH_Likely ? Stmt::LH_None : LH);
|
|
EmitBlock(LHSFalse);
|
|
}
|
|
|
|
incrementProfileCounter(CondBOp);
|
|
setCurrentProfileCount(getProfileCount(CondBOp->getRHS()));
|
|
|
|
// Any temporaries created here are conditional.
|
|
eval.begin(*this);
|
|
EmitBranchToCounterBlock(CondBOp->getRHS(), BO_LOr, TrueBlock, FalseBlock,
|
|
RHSCount, LH);
|
|
|
|
eval.end(*this);
|
|
|
|
return;
|
|
}
|
|
}
|
|
|
|
if (const UnaryOperator *CondUOp = dyn_cast<UnaryOperator>(Cond)) {
|
|
// br(!x, t, f) -> br(x, f, t)
|
|
if (CondUOp->getOpcode() == UO_LNot) {
|
|
// Negate the count.
|
|
uint64_t FalseCount = getCurrentProfileCount() - TrueCount;
|
|
// The values of the enum are chosen to make this negation possible.
|
|
LH = static_cast<Stmt::Likelihood>(-LH);
|
|
// Negate the condition and swap the destination blocks.
|
|
return EmitBranchOnBoolExpr(CondUOp->getSubExpr(), FalseBlock, TrueBlock,
|
|
FalseCount, LH);
|
|
}
|
|
}
|
|
|
|
if (const ConditionalOperator *CondOp = dyn_cast<ConditionalOperator>(Cond)) {
|
|
// br(c ? x : y, t, f) -> br(c, br(x, t, f), br(y, t, f))
|
|
llvm::BasicBlock *LHSBlock = createBasicBlock("cond.true");
|
|
llvm::BasicBlock *RHSBlock = createBasicBlock("cond.false");
|
|
|
|
// The ConditionalOperator itself has no likelihood information for its
|
|
// true and false branches. This matches the behavior of __builtin_expect.
|
|
ConditionalEvaluation cond(*this);
|
|
EmitBranchOnBoolExpr(CondOp->getCond(), LHSBlock, RHSBlock,
|
|
getProfileCount(CondOp), Stmt::LH_None);
|
|
|
|
// When computing PGO branch weights, we only know the overall count for
|
|
// the true block. This code is essentially doing tail duplication of the
|
|
// naive code-gen, introducing new edges for which counts are not
|
|
// available. Divide the counts proportionally between the LHS and RHS of
|
|
// the conditional operator.
|
|
uint64_t LHSScaledTrueCount = 0;
|
|
if (TrueCount) {
|
|
double LHSRatio =
|
|
getProfileCount(CondOp) / (double)getCurrentProfileCount();
|
|
LHSScaledTrueCount = TrueCount * LHSRatio;
|
|
}
|
|
|
|
cond.begin(*this);
|
|
EmitBlock(LHSBlock);
|
|
incrementProfileCounter(CondOp);
|
|
{
|
|
ApplyDebugLocation DL(*this, Cond);
|
|
EmitBranchOnBoolExpr(CondOp->getLHS(), TrueBlock, FalseBlock,
|
|
LHSScaledTrueCount, LH);
|
|
}
|
|
cond.end(*this);
|
|
|
|
cond.begin(*this);
|
|
EmitBlock(RHSBlock);
|
|
EmitBranchOnBoolExpr(CondOp->getRHS(), TrueBlock, FalseBlock,
|
|
TrueCount - LHSScaledTrueCount, LH);
|
|
cond.end(*this);
|
|
|
|
return;
|
|
}
|
|
|
|
if (const CXXThrowExpr *Throw = dyn_cast<CXXThrowExpr>(Cond)) {
|
|
// Conditional operator handling can give us a throw expression as a
|
|
// condition for a case like:
|
|
// br(c ? throw x : y, t, f) -> br(c, br(throw x, t, f), br(y, t, f)
|
|
// Fold this to:
|
|
// br(c, throw x, br(y, t, f))
|
|
EmitCXXThrowExpr(Throw, /*KeepInsertionPoint*/false);
|
|
return;
|
|
}
|
|
|
|
// Emit the code with the fully general case.
|
|
llvm::Value *CondV;
|
|
{
|
|
ApplyDebugLocation DL(*this, Cond);
|
|
CondV = EvaluateExprAsBool(Cond);
|
|
}
|
|
|
|
llvm::MDNode *Weights = nullptr;
|
|
llvm::MDNode *Unpredictable = nullptr;
|
|
|
|
// If the branch has a condition wrapped by __builtin_unpredictable,
|
|
// create metadata that specifies that the branch is unpredictable.
|
|
// Don't bother if not optimizing because that metadata would not be used.
|
|
auto *Call = dyn_cast<CallExpr>(Cond->IgnoreImpCasts());
|
|
if (Call && CGM.getCodeGenOpts().OptimizationLevel != 0) {
|
|
auto *FD = dyn_cast_or_null<FunctionDecl>(Call->getCalleeDecl());
|
|
if (FD && FD->getBuiltinID() == Builtin::BI__builtin_unpredictable) {
|
|
llvm::MDBuilder MDHelper(getLLVMContext());
|
|
Unpredictable = MDHelper.createUnpredictable();
|
|
}
|
|
}
|
|
|
|
// If there is a Likelihood knowledge for the cond, lower it.
|
|
// Note that if not optimizing this won't emit anything.
|
|
llvm::Value *NewCondV = emitCondLikelihoodViaExpectIntrinsic(CondV, LH);
|
|
if (CondV != NewCondV)
|
|
CondV = NewCondV;
|
|
else {
|
|
// Otherwise, lower profile counts. Note that we do this even at -O0.
|
|
uint64_t CurrentCount = std::max(getCurrentProfileCount(), TrueCount);
|
|
Weights = createProfileWeights(TrueCount, CurrentCount - TrueCount);
|
|
}
|
|
|
|
Builder.CreateCondBr(CondV, TrueBlock, FalseBlock, Weights, Unpredictable);
|
|
}
|
|
|
|
/// ErrorUnsupported - Print out an error that codegen doesn't support the
|
|
/// specified stmt yet.
|
|
void CodeGenFunction::ErrorUnsupported(const Stmt *S, const char *Type) {
|
|
CGM.ErrorUnsupported(S, Type);
|
|
}
|
|
|
|
/// emitNonZeroVLAInit - Emit the "zero" initialization of a
|
|
/// variable-length array whose elements have a non-zero bit-pattern.
|
|
///
|
|
/// \param baseType the inner-most element type of the array
|
|
/// \param src - a char* pointing to the bit-pattern for a single
|
|
/// base element of the array
|
|
/// \param sizeInChars - the total size of the VLA, in chars
|
|
static void emitNonZeroVLAInit(CodeGenFunction &CGF, QualType baseType,
|
|
Address dest, Address src,
|
|
llvm::Value *sizeInChars) {
|
|
CGBuilderTy &Builder = CGF.Builder;
|
|
|
|
CharUnits baseSize = CGF.getContext().getTypeSizeInChars(baseType);
|
|
llvm::Value *baseSizeInChars
|
|
= llvm::ConstantInt::get(CGF.IntPtrTy, baseSize.getQuantity());
|
|
|
|
Address begin =
|
|
Builder.CreateElementBitCast(dest, CGF.Int8Ty, "vla.begin");
|
|
llvm::Value *end = Builder.CreateInBoundsGEP(
|
|
begin.getElementType(), begin.getPointer(), sizeInChars, "vla.end");
|
|
|
|
llvm::BasicBlock *originBB = CGF.Builder.GetInsertBlock();
|
|
llvm::BasicBlock *loopBB = CGF.createBasicBlock("vla-init.loop");
|
|
llvm::BasicBlock *contBB = CGF.createBasicBlock("vla-init.cont");
|
|
|
|
// Make a loop over the VLA. C99 guarantees that the VLA element
|
|
// count must be nonzero.
|
|
CGF.EmitBlock(loopBB);
|
|
|
|
llvm::PHINode *cur = Builder.CreatePHI(begin.getType(), 2, "vla.cur");
|
|
cur->addIncoming(begin.getPointer(), originBB);
|
|
|
|
CharUnits curAlign =
|
|
dest.getAlignment().alignmentOfArrayElement(baseSize);
|
|
|
|
// memcpy the individual element bit-pattern.
|
|
Builder.CreateMemCpy(Address(cur, curAlign), src, baseSizeInChars,
|
|
/*volatile*/ false);
|
|
|
|
// Go to the next element.
|
|
llvm::Value *next =
|
|
Builder.CreateInBoundsGEP(CGF.Int8Ty, cur, baseSizeInChars, "vla.next");
|
|
|
|
// Leave if that's the end of the VLA.
|
|
llvm::Value *done = Builder.CreateICmpEQ(next, end, "vla-init.isdone");
|
|
Builder.CreateCondBr(done, contBB, loopBB);
|
|
cur->addIncoming(next, loopBB);
|
|
|
|
CGF.EmitBlock(contBB);
|
|
}
|
|
|
|
void
|
|
CodeGenFunction::EmitNullInitialization(Address DestPtr, QualType Ty) {
|
|
// Ignore empty classes in C++.
|
|
if (getLangOpts().CPlusPlus) {
|
|
if (const RecordType *RT = Ty->getAs<RecordType>()) {
|
|
if (cast<CXXRecordDecl>(RT->getDecl())->isEmpty())
|
|
return;
|
|
}
|
|
}
|
|
|
|
// Cast the dest ptr to the appropriate i8 pointer type.
|
|
if (DestPtr.getElementType() != Int8Ty)
|
|
DestPtr = Builder.CreateElementBitCast(DestPtr, Int8Ty);
|
|
|
|
// Get size and alignment info for this aggregate.
|
|
CharUnits size = getContext().getTypeSizeInChars(Ty);
|
|
|
|
llvm::Value *SizeVal;
|
|
const VariableArrayType *vla;
|
|
|
|
// Don't bother emitting a zero-byte memset.
|
|
if (size.isZero()) {
|
|
// But note that getTypeInfo returns 0 for a VLA.
|
|
if (const VariableArrayType *vlaType =
|
|
dyn_cast_or_null<VariableArrayType>(
|
|
getContext().getAsArrayType(Ty))) {
|
|
auto VlaSize = getVLASize(vlaType);
|
|
SizeVal = VlaSize.NumElts;
|
|
CharUnits eltSize = getContext().getTypeSizeInChars(VlaSize.Type);
|
|
if (!eltSize.isOne())
|
|
SizeVal = Builder.CreateNUWMul(SizeVal, CGM.getSize(eltSize));
|
|
vla = vlaType;
|
|
} else {
|
|
return;
|
|
}
|
|
} else {
|
|
SizeVal = CGM.getSize(size);
|
|
vla = nullptr;
|
|
}
|
|
|
|
// If the type contains a pointer to data member we can't memset it to zero.
|
|
// Instead, create a null constant and copy it to the destination.
|
|
// TODO: there are other patterns besides zero that we can usefully memset,
|
|
// like -1, which happens to be the pattern used by member-pointers.
|
|
if (!CGM.getTypes().isZeroInitializable(Ty)) {
|
|
// For a VLA, emit a single element, then splat that over the VLA.
|
|
if (vla) Ty = getContext().getBaseElementType(vla);
|
|
|
|
llvm::Constant *NullConstant = CGM.EmitNullConstant(Ty);
|
|
|
|
llvm::GlobalVariable *NullVariable =
|
|
new llvm::GlobalVariable(CGM.getModule(), NullConstant->getType(),
|
|
/*isConstant=*/true,
|
|
llvm::GlobalVariable::PrivateLinkage,
|
|
NullConstant, Twine());
|
|
CharUnits NullAlign = DestPtr.getAlignment();
|
|
NullVariable->setAlignment(NullAlign.getAsAlign());
|
|
Address SrcPtr(Builder.CreateBitCast(NullVariable, Builder.getInt8PtrTy()),
|
|
NullAlign);
|
|
|
|
if (vla) return emitNonZeroVLAInit(*this, Ty, DestPtr, SrcPtr, SizeVal);
|
|
|
|
// Get and call the appropriate llvm.memcpy overload.
|
|
Builder.CreateMemCpy(DestPtr, SrcPtr, SizeVal, false);
|
|
return;
|
|
}
|
|
|
|
// Otherwise, just memset the whole thing to zero. This is legal
|
|
// because in LLVM, all default initializers (other than the ones we just
|
|
// handled above) are guaranteed to have a bit pattern of all zeros.
|
|
Builder.CreateMemSet(DestPtr, Builder.getInt8(0), SizeVal, false);
|
|
}
|
|
|
|
llvm::BlockAddress *CodeGenFunction::GetAddrOfLabel(const LabelDecl *L) {
|
|
// Make sure that there is a block for the indirect goto.
|
|
if (!IndirectBranch)
|
|
GetIndirectGotoBlock();
|
|
|
|
llvm::BasicBlock *BB = getJumpDestForLabel(L).getBlock();
|
|
|
|
// Make sure the indirect branch includes all of the address-taken blocks.
|
|
IndirectBranch->addDestination(BB);
|
|
return llvm::BlockAddress::get(CurFn, BB);
|
|
}
|
|
|
|
llvm::BasicBlock *CodeGenFunction::GetIndirectGotoBlock() {
|
|
// If we already made the indirect branch for indirect goto, return its block.
|
|
if (IndirectBranch) return IndirectBranch->getParent();
|
|
|
|
CGBuilderTy TmpBuilder(*this, createBasicBlock("indirectgoto"));
|
|
|
|
// Create the PHI node that indirect gotos will add entries to.
|
|
llvm::Value *DestVal = TmpBuilder.CreatePHI(Int8PtrTy, 0,
|
|
"indirect.goto.dest");
|
|
|
|
// Create the indirect branch instruction.
|
|
IndirectBranch = TmpBuilder.CreateIndirectBr(DestVal);
|
|
return IndirectBranch->getParent();
|
|
}
|
|
|
|
/// Computes the length of an array in elements, as well as the base
|
|
/// element type and a properly-typed first element pointer.
|
|
llvm::Value *CodeGenFunction::emitArrayLength(const ArrayType *origArrayType,
|
|
QualType &baseType,
|
|
Address &addr) {
|
|
const ArrayType *arrayType = origArrayType;
|
|
|
|
// If it's a VLA, we have to load the stored size. Note that
|
|
// this is the size of the VLA in bytes, not its size in elements.
|
|
llvm::Value *numVLAElements = nullptr;
|
|
if (isa<VariableArrayType>(arrayType)) {
|
|
numVLAElements = getVLASize(cast<VariableArrayType>(arrayType)).NumElts;
|
|
|
|
// Walk into all VLAs. This doesn't require changes to addr,
|
|
// which has type T* where T is the first non-VLA element type.
|
|
do {
|
|
QualType elementType = arrayType->getElementType();
|
|
arrayType = getContext().getAsArrayType(elementType);
|
|
|
|
// If we only have VLA components, 'addr' requires no adjustment.
|
|
if (!arrayType) {
|
|
baseType = elementType;
|
|
return numVLAElements;
|
|
}
|
|
} while (isa<VariableArrayType>(arrayType));
|
|
|
|
// We get out here only if we find a constant array type
|
|
// inside the VLA.
|
|
}
|
|
|
|
// We have some number of constant-length arrays, so addr should
|
|
// have LLVM type [M x [N x [...]]]*. Build a GEP that walks
|
|
// down to the first element of addr.
|
|
SmallVector<llvm::Value*, 8> gepIndices;
|
|
|
|
// GEP down to the array type.
|
|
llvm::ConstantInt *zero = Builder.getInt32(0);
|
|
gepIndices.push_back(zero);
|
|
|
|
uint64_t countFromCLAs = 1;
|
|
QualType eltType;
|
|
|
|
llvm::ArrayType *llvmArrayType =
|
|
dyn_cast<llvm::ArrayType>(addr.getElementType());
|
|
while (llvmArrayType) {
|
|
assert(isa<ConstantArrayType>(arrayType));
|
|
assert(cast<ConstantArrayType>(arrayType)->getSize().getZExtValue()
|
|
== llvmArrayType->getNumElements());
|
|
|
|
gepIndices.push_back(zero);
|
|
countFromCLAs *= llvmArrayType->getNumElements();
|
|
eltType = arrayType->getElementType();
|
|
|
|
llvmArrayType =
|
|
dyn_cast<llvm::ArrayType>(llvmArrayType->getElementType());
|
|
arrayType = getContext().getAsArrayType(arrayType->getElementType());
|
|
assert((!llvmArrayType || arrayType) &&
|
|
"LLVM and Clang types are out-of-synch");
|
|
}
|
|
|
|
if (arrayType) {
|
|
// From this point onwards, the Clang array type has been emitted
|
|
// as some other type (probably a packed struct). Compute the array
|
|
// size, and just emit the 'begin' expression as a bitcast.
|
|
while (arrayType) {
|
|
countFromCLAs *=
|
|
cast<ConstantArrayType>(arrayType)->getSize().getZExtValue();
|
|
eltType = arrayType->getElementType();
|
|
arrayType = getContext().getAsArrayType(eltType);
|
|
}
|
|
|
|
llvm::Type *baseType = ConvertType(eltType);
|
|
addr = Builder.CreateElementBitCast(addr, baseType, "array.begin");
|
|
} else {
|
|
// Create the actual GEP.
|
|
addr = Address(Builder.CreateInBoundsGEP(
|
|
addr.getElementType(), addr.getPointer(), gepIndices, "array.begin"),
|
|
ConvertTypeForMem(eltType),
|
|
addr.getAlignment());
|
|
}
|
|
|
|
baseType = eltType;
|
|
|
|
llvm::Value *numElements
|
|
= llvm::ConstantInt::get(SizeTy, countFromCLAs);
|
|
|
|
// If we had any VLA dimensions, factor them in.
|
|
if (numVLAElements)
|
|
numElements = Builder.CreateNUWMul(numVLAElements, numElements);
|
|
|
|
return numElements;
|
|
}
|
|
|
|
CodeGenFunction::VlaSizePair CodeGenFunction::getVLASize(QualType type) {
|
|
const VariableArrayType *vla = getContext().getAsVariableArrayType(type);
|
|
assert(vla && "type was not a variable array type!");
|
|
return getVLASize(vla);
|
|
}
|
|
|
|
CodeGenFunction::VlaSizePair
|
|
CodeGenFunction::getVLASize(const VariableArrayType *type) {
|
|
// The number of elements so far; always size_t.
|
|
llvm::Value *numElements = nullptr;
|
|
|
|
QualType elementType;
|
|
do {
|
|
elementType = type->getElementType();
|
|
llvm::Value *vlaSize = VLASizeMap[type->getSizeExpr()];
|
|
assert(vlaSize && "no size for VLA!");
|
|
assert(vlaSize->getType() == SizeTy);
|
|
|
|
if (!numElements) {
|
|
numElements = vlaSize;
|
|
} else {
|
|
// It's undefined behavior if this wraps around, so mark it that way.
|
|
// FIXME: Teach -fsanitize=undefined to trap this.
|
|
numElements = Builder.CreateNUWMul(numElements, vlaSize);
|
|
}
|
|
} while ((type = getContext().getAsVariableArrayType(elementType)));
|
|
|
|
return { numElements, elementType };
|
|
}
|
|
|
|
CodeGenFunction::VlaSizePair
|
|
CodeGenFunction::getVLAElements1D(QualType type) {
|
|
const VariableArrayType *vla = getContext().getAsVariableArrayType(type);
|
|
assert(vla && "type was not a variable array type!");
|
|
return getVLAElements1D(vla);
|
|
}
|
|
|
|
CodeGenFunction::VlaSizePair
|
|
CodeGenFunction::getVLAElements1D(const VariableArrayType *Vla) {
|
|
llvm::Value *VlaSize = VLASizeMap[Vla->getSizeExpr()];
|
|
assert(VlaSize && "no size for VLA!");
|
|
assert(VlaSize->getType() == SizeTy);
|
|
return { VlaSize, Vla->getElementType() };
|
|
}
|
|
|
|
void CodeGenFunction::EmitVariablyModifiedType(QualType type) {
|
|
assert(type->isVariablyModifiedType() &&
|
|
"Must pass variably modified type to EmitVLASizes!");
|
|
|
|
EnsureInsertPoint();
|
|
|
|
// We're going to walk down into the type and look for VLA
|
|
// expressions.
|
|
do {
|
|
assert(type->isVariablyModifiedType());
|
|
|
|
const Type *ty = type.getTypePtr();
|
|
switch (ty->getTypeClass()) {
|
|
|
|
#define TYPE(Class, Base)
|
|
#define ABSTRACT_TYPE(Class, Base)
|
|
#define NON_CANONICAL_TYPE(Class, Base)
|
|
#define DEPENDENT_TYPE(Class, Base) case Type::Class:
|
|
#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)
|
|
#include "clang/AST/TypeNodes.inc"
|
|
llvm_unreachable("unexpected dependent type!");
|
|
|
|
// These types are never variably-modified.
|
|
case Type::Builtin:
|
|
case Type::Complex:
|
|
case Type::Vector:
|
|
case Type::ExtVector:
|
|
case Type::ConstantMatrix:
|
|
case Type::Record:
|
|
case Type::Enum:
|
|
case Type::Elaborated:
|
|
case Type::Using:
|
|
case Type::TemplateSpecialization:
|
|
case Type::ObjCTypeParam:
|
|
case Type::ObjCObject:
|
|
case Type::ObjCInterface:
|
|
case Type::ObjCObjectPointer:
|
|
case Type::BitInt:
|
|
llvm_unreachable("type class is never variably-modified!");
|
|
|
|
case Type::Adjusted:
|
|
type = cast<AdjustedType>(ty)->getAdjustedType();
|
|
break;
|
|
|
|
case Type::Decayed:
|
|
type = cast<DecayedType>(ty)->getPointeeType();
|
|
break;
|
|
|
|
case Type::Pointer:
|
|
type = cast<PointerType>(ty)->getPointeeType();
|
|
break;
|
|
|
|
case Type::BlockPointer:
|
|
type = cast<BlockPointerType>(ty)->getPointeeType();
|
|
break;
|
|
|
|
case Type::LValueReference:
|
|
case Type::RValueReference:
|
|
type = cast<ReferenceType>(ty)->getPointeeType();
|
|
break;
|
|
|
|
case Type::MemberPointer:
|
|
type = cast<MemberPointerType>(ty)->getPointeeType();
|
|
break;
|
|
|
|
case Type::ConstantArray:
|
|
case Type::IncompleteArray:
|
|
// Losing element qualification here is fine.
|
|
type = cast<ArrayType>(ty)->getElementType();
|
|
break;
|
|
|
|
case Type::VariableArray: {
|
|
// Losing element qualification here is fine.
|
|
const VariableArrayType *vat = cast<VariableArrayType>(ty);
|
|
|
|
// Unknown size indication requires no size computation.
|
|
// Otherwise, evaluate and record it.
|
|
if (const Expr *sizeExpr = vat->getSizeExpr()) {
|
|
// It's possible that we might have emitted this already,
|
|
// e.g. with a typedef and a pointer to it.
|
|
llvm::Value *&entry = VLASizeMap[sizeExpr];
|
|
if (!entry) {
|
|
llvm::Value *size = EmitScalarExpr(sizeExpr);
|
|
|
|
// C11 6.7.6.2p5:
|
|
// If the size is an expression that is not an integer constant
|
|
// expression [...] each time it is evaluated it shall have a value
|
|
// greater than zero.
|
|
if (SanOpts.has(SanitizerKind::VLABound)) {
|
|
SanitizerScope SanScope(this);
|
|
llvm::Value *Zero = llvm::Constant::getNullValue(size->getType());
|
|
clang::QualType SEType = sizeExpr->getType();
|
|
llvm::Value *CheckCondition =
|
|
SEType->isSignedIntegerType()
|
|
? Builder.CreateICmpSGT(size, Zero)
|
|
: Builder.CreateICmpUGT(size, Zero);
|
|
llvm::Constant *StaticArgs[] = {
|
|
EmitCheckSourceLocation(sizeExpr->getBeginLoc()),
|
|
EmitCheckTypeDescriptor(SEType)};
|
|
EmitCheck(std::make_pair(CheckCondition, SanitizerKind::VLABound),
|
|
SanitizerHandler::VLABoundNotPositive, StaticArgs, size);
|
|
}
|
|
|
|
// Always zexting here would be wrong if it weren't
|
|
// undefined behavior to have a negative bound.
|
|
// FIXME: What about when size's type is larger than size_t?
|
|
entry = Builder.CreateIntCast(size, SizeTy, /*signed*/ false);
|
|
}
|
|
}
|
|
type = vat->getElementType();
|
|
break;
|
|
}
|
|
|
|
case Type::FunctionProto:
|
|
case Type::FunctionNoProto:
|
|
type = cast<FunctionType>(ty)->getReturnType();
|
|
break;
|
|
|
|
case Type::Paren:
|
|
case Type::TypeOf:
|
|
case Type::UnaryTransform:
|
|
case Type::Attributed:
|
|
case Type::SubstTemplateTypeParm:
|
|
case Type::MacroQualified:
|
|
// Keep walking after single level desugaring.
|
|
type = type.getSingleStepDesugaredType(getContext());
|
|
break;
|
|
|
|
case Type::Typedef:
|
|
case Type::Decltype:
|
|
case Type::Auto:
|
|
case Type::DeducedTemplateSpecialization:
|
|
// Stop walking: nothing to do.
|
|
return;
|
|
|
|
case Type::TypeOfExpr:
|
|
// Stop walking: emit typeof expression.
|
|
EmitIgnoredExpr(cast<TypeOfExprType>(ty)->getUnderlyingExpr());
|
|
return;
|
|
|
|
case Type::Atomic:
|
|
type = cast<AtomicType>(ty)->getValueType();
|
|
break;
|
|
|
|
case Type::Pipe:
|
|
type = cast<PipeType>(ty)->getElementType();
|
|
break;
|
|
}
|
|
} while (type->isVariablyModifiedType());
|
|
}
|
|
|
|
Address CodeGenFunction::EmitVAListRef(const Expr* E) {
|
|
if (getContext().getBuiltinVaListType()->isArrayType())
|
|
return EmitPointerWithAlignment(E);
|
|
return EmitLValue(E).getAddress(*this);
|
|
}
|
|
|
|
Address CodeGenFunction::EmitMSVAListRef(const Expr *E) {
|
|
return EmitLValue(E).getAddress(*this);
|
|
}
|
|
|
|
void CodeGenFunction::EmitDeclRefExprDbgValue(const DeclRefExpr *E,
|
|
const APValue &Init) {
|
|
assert(Init.hasValue() && "Invalid DeclRefExpr initializer!");
|
|
if (CGDebugInfo *Dbg = getDebugInfo())
|
|
if (CGM.getCodeGenOpts().hasReducedDebugInfo())
|
|
Dbg->EmitGlobalVariable(E->getDecl(), Init);
|
|
}
|
|
|
|
CodeGenFunction::PeepholeProtection
|
|
CodeGenFunction::protectFromPeepholes(RValue rvalue) {
|
|
// At the moment, the only aggressive peephole we do in IR gen
|
|
// is trunc(zext) folding, but if we add more, we can easily
|
|
// extend this protection.
|
|
|
|
if (!rvalue.isScalar()) return PeepholeProtection();
|
|
llvm::Value *value = rvalue.getScalarVal();
|
|
if (!isa<llvm::ZExtInst>(value)) return PeepholeProtection();
|
|
|
|
// Just make an extra bitcast.
|
|
assert(HaveInsertPoint());
|
|
llvm::Instruction *inst = new llvm::BitCastInst(value, value->getType(), "",
|
|
Builder.GetInsertBlock());
|
|
|
|
PeepholeProtection protection;
|
|
protection.Inst = inst;
|
|
return protection;
|
|
}
|
|
|
|
void CodeGenFunction::unprotectFromPeepholes(PeepholeProtection protection) {
|
|
if (!protection.Inst) return;
|
|
|
|
// In theory, we could try to duplicate the peepholes now, but whatever.
|
|
protection.Inst->eraseFromParent();
|
|
}
|
|
|
|
void CodeGenFunction::emitAlignmentAssumption(llvm::Value *PtrValue,
|
|
QualType Ty, SourceLocation Loc,
|
|
SourceLocation AssumptionLoc,
|
|
llvm::Value *Alignment,
|
|
llvm::Value *OffsetValue) {
|
|
if (Alignment->getType() != IntPtrTy)
|
|
Alignment =
|
|
Builder.CreateIntCast(Alignment, IntPtrTy, false, "casted.align");
|
|
if (OffsetValue && OffsetValue->getType() != IntPtrTy)
|
|
OffsetValue =
|
|
Builder.CreateIntCast(OffsetValue, IntPtrTy, true, "casted.offset");
|
|
llvm::Value *TheCheck = nullptr;
|
|
if (SanOpts.has(SanitizerKind::Alignment)) {
|
|
llvm::Value *PtrIntValue =
|
|
Builder.CreatePtrToInt(PtrValue, IntPtrTy, "ptrint");
|
|
|
|
if (OffsetValue) {
|
|
bool IsOffsetZero = false;
|
|
if (const auto *CI = dyn_cast<llvm::ConstantInt>(OffsetValue))
|
|
IsOffsetZero = CI->isZero();
|
|
|
|
if (!IsOffsetZero)
|
|
PtrIntValue = Builder.CreateSub(PtrIntValue, OffsetValue, "offsetptr");
|
|
}
|
|
|
|
llvm::Value *Zero = llvm::ConstantInt::get(IntPtrTy, 0);
|
|
llvm::Value *Mask =
|
|
Builder.CreateSub(Alignment, llvm::ConstantInt::get(IntPtrTy, 1));
|
|
llvm::Value *MaskedPtr = Builder.CreateAnd(PtrIntValue, Mask, "maskedptr");
|
|
TheCheck = Builder.CreateICmpEQ(MaskedPtr, Zero, "maskcond");
|
|
}
|
|
llvm::Instruction *Assumption = Builder.CreateAlignmentAssumption(
|
|
CGM.getDataLayout(), PtrValue, Alignment, OffsetValue);
|
|
|
|
if (!SanOpts.has(SanitizerKind::Alignment))
|
|
return;
|
|
emitAlignmentAssumptionCheck(PtrValue, Ty, Loc, AssumptionLoc, Alignment,
|
|
OffsetValue, TheCheck, Assumption);
|
|
}
|
|
|
|
void CodeGenFunction::emitAlignmentAssumption(llvm::Value *PtrValue,
|
|
const Expr *E,
|
|
SourceLocation AssumptionLoc,
|
|
llvm::Value *Alignment,
|
|
llvm::Value *OffsetValue) {
|
|
if (auto *CE = dyn_cast<CastExpr>(E))
|
|
E = CE->getSubExprAsWritten();
|
|
QualType Ty = E->getType();
|
|
SourceLocation Loc = E->getExprLoc();
|
|
|
|
emitAlignmentAssumption(PtrValue, Ty, Loc, AssumptionLoc, Alignment,
|
|
OffsetValue);
|
|
}
|
|
|
|
llvm::Value *CodeGenFunction::EmitAnnotationCall(llvm::Function *AnnotationFn,
|
|
llvm::Value *AnnotatedVal,
|
|
StringRef AnnotationStr,
|
|
SourceLocation Location,
|
|
const AnnotateAttr *Attr) {
|
|
SmallVector<llvm::Value *, 5> Args = {
|
|
AnnotatedVal,
|
|
Builder.CreateBitCast(CGM.EmitAnnotationString(AnnotationStr), Int8PtrTy),
|
|
Builder.CreateBitCast(CGM.EmitAnnotationUnit(Location), Int8PtrTy),
|
|
CGM.EmitAnnotationLineNo(Location),
|
|
};
|
|
if (Attr)
|
|
Args.push_back(CGM.EmitAnnotationArgs(Attr));
|
|
return Builder.CreateCall(AnnotationFn, Args);
|
|
}
|
|
|
|
void CodeGenFunction::EmitVarAnnotations(const VarDecl *D, llvm::Value *V) {
|
|
assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute");
|
|
// FIXME We create a new bitcast for every annotation because that's what
|
|
// llvm-gcc was doing.
|
|
for (const auto *I : D->specific_attrs<AnnotateAttr>())
|
|
EmitAnnotationCall(CGM.getIntrinsic(llvm::Intrinsic::var_annotation),
|
|
Builder.CreateBitCast(V, CGM.Int8PtrTy, V->getName()),
|
|
I->getAnnotation(), D->getLocation(), I);
|
|
}
|
|
|
|
Address CodeGenFunction::EmitFieldAnnotations(const FieldDecl *D,
|
|
Address Addr) {
|
|
assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute");
|
|
llvm::Value *V = Addr.getPointer();
|
|
llvm::Type *VTy = V->getType();
|
|
auto *PTy = dyn_cast<llvm::PointerType>(VTy);
|
|
unsigned AS = PTy ? PTy->getAddressSpace() : 0;
|
|
llvm::PointerType *IntrinTy =
|
|
llvm::PointerType::getWithSamePointeeType(CGM.Int8PtrTy, AS);
|
|
llvm::Function *F =
|
|
CGM.getIntrinsic(llvm::Intrinsic::ptr_annotation, IntrinTy);
|
|
|
|
for (const auto *I : D->specific_attrs<AnnotateAttr>()) {
|
|
// FIXME Always emit the cast inst so we can differentiate between
|
|
// annotation on the first field of a struct and annotation on the struct
|
|
// itself.
|
|
if (VTy != IntrinTy)
|
|
V = Builder.CreateBitCast(V, IntrinTy);
|
|
V = EmitAnnotationCall(F, V, I->getAnnotation(), D->getLocation(), I);
|
|
V = Builder.CreateBitCast(V, VTy);
|
|
}
|
|
|
|
return Address(V, Addr.getAlignment());
|
|
}
|
|
|
|
CodeGenFunction::CGCapturedStmtInfo::~CGCapturedStmtInfo() { }
|
|
|
|
CodeGenFunction::SanitizerScope::SanitizerScope(CodeGenFunction *CGF)
|
|
: CGF(CGF) {
|
|
assert(!CGF->IsSanitizerScope);
|
|
CGF->IsSanitizerScope = true;
|
|
}
|
|
|
|
CodeGenFunction::SanitizerScope::~SanitizerScope() {
|
|
CGF->IsSanitizerScope = false;
|
|
}
|
|
|
|
void CodeGenFunction::InsertHelper(llvm::Instruction *I,
|
|
const llvm::Twine &Name,
|
|
llvm::BasicBlock *BB,
|
|
llvm::BasicBlock::iterator InsertPt) const {
|
|
LoopStack.InsertHelper(I);
|
|
if (IsSanitizerScope)
|
|
CGM.getSanitizerMetadata()->disableSanitizerForInstruction(I);
|
|
}
|
|
|
|
void CGBuilderInserter::InsertHelper(
|
|
llvm::Instruction *I, const llvm::Twine &Name, llvm::BasicBlock *BB,
|
|
llvm::BasicBlock::iterator InsertPt) const {
|
|
llvm::IRBuilderDefaultInserter::InsertHelper(I, Name, BB, InsertPt);
|
|
if (CGF)
|
|
CGF->InsertHelper(I, Name, BB, InsertPt);
|
|
}
|
|
|
|
// Emits an error if we don't have a valid set of target features for the
|
|
// called function.
|
|
void CodeGenFunction::checkTargetFeatures(const CallExpr *E,
|
|
const FunctionDecl *TargetDecl) {
|
|
return checkTargetFeatures(E->getBeginLoc(), TargetDecl);
|
|
}
|
|
|
|
// Emits an error if we don't have a valid set of target features for the
|
|
// called function.
|
|
void CodeGenFunction::checkTargetFeatures(SourceLocation Loc,
|
|
const FunctionDecl *TargetDecl) {
|
|
// Early exit if this is an indirect call.
|
|
if (!TargetDecl)
|
|
return;
|
|
|
|
// Get the current enclosing function if it exists. If it doesn't
|
|
// we can't check the target features anyhow.
|
|
const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(CurCodeDecl);
|
|
if (!FD)
|
|
return;
|
|
|
|
// Grab the required features for the call. For a builtin this is listed in
|
|
// the td file with the default cpu, for an always_inline function this is any
|
|
// listed cpu and any listed features.
|
|
unsigned BuiltinID = TargetDecl->getBuiltinID();
|
|
std::string MissingFeature;
|
|
llvm::StringMap<bool> CallerFeatureMap;
|
|
CGM.getContext().getFunctionFeatureMap(CallerFeatureMap, FD);
|
|
if (BuiltinID) {
|
|
StringRef FeatureList(
|
|
CGM.getContext().BuiltinInfo.getRequiredFeatures(BuiltinID));
|
|
// Return if the builtin doesn't have any required features.
|
|
if (FeatureList.empty())
|
|
return;
|
|
assert(!FeatureList.contains(' ') && "Space in feature list");
|
|
TargetFeatures TF(CallerFeatureMap);
|
|
if (!TF.hasRequiredFeatures(FeatureList))
|
|
CGM.getDiags().Report(Loc, diag::err_builtin_needs_feature)
|
|
<< TargetDecl->getDeclName() << FeatureList;
|
|
} else if (!TargetDecl->isMultiVersion() &&
|
|
TargetDecl->hasAttr<TargetAttr>()) {
|
|
// Get the required features for the callee.
|
|
|
|
const TargetAttr *TD = TargetDecl->getAttr<TargetAttr>();
|
|
ParsedTargetAttr ParsedAttr =
|
|
CGM.getContext().filterFunctionTargetAttrs(TD);
|
|
|
|
SmallVector<StringRef, 1> ReqFeatures;
|
|
llvm::StringMap<bool> CalleeFeatureMap;
|
|
CGM.getContext().getFunctionFeatureMap(CalleeFeatureMap, TargetDecl);
|
|
|
|
for (const auto &F : ParsedAttr.Features) {
|
|
if (F[0] == '+' && CalleeFeatureMap.lookup(F.substr(1)))
|
|
ReqFeatures.push_back(StringRef(F).substr(1));
|
|
}
|
|
|
|
for (const auto &F : CalleeFeatureMap) {
|
|
// Only positive features are "required".
|
|
if (F.getValue())
|
|
ReqFeatures.push_back(F.getKey());
|
|
}
|
|
if (!llvm::all_of(ReqFeatures, [&](StringRef Feature) {
|
|
if (!CallerFeatureMap.lookup(Feature)) {
|
|
MissingFeature = Feature.str();
|
|
return false;
|
|
}
|
|
return true;
|
|
}))
|
|
CGM.getDiags().Report(Loc, diag::err_function_needs_feature)
|
|
<< FD->getDeclName() << TargetDecl->getDeclName() << MissingFeature;
|
|
}
|
|
}
|
|
|
|
void CodeGenFunction::EmitSanitizerStatReport(llvm::SanitizerStatKind SSK) {
|
|
if (!CGM.getCodeGenOpts().SanitizeStats)
|
|
return;
|
|
|
|
llvm::IRBuilder<> IRB(Builder.GetInsertBlock(), Builder.GetInsertPoint());
|
|
IRB.SetCurrentDebugLocation(Builder.getCurrentDebugLocation());
|
|
CGM.getSanStats().create(IRB, SSK);
|
|
}
|
|
|
|
llvm::Value *
|
|
CodeGenFunction::FormResolverCondition(const MultiVersionResolverOption &RO) {
|
|
llvm::Value *Condition = nullptr;
|
|
|
|
if (!RO.Conditions.Architecture.empty())
|
|
Condition = EmitX86CpuIs(RO.Conditions.Architecture);
|
|
|
|
if (!RO.Conditions.Features.empty()) {
|
|
llvm::Value *FeatureCond = EmitX86CpuSupports(RO.Conditions.Features);
|
|
Condition =
|
|
Condition ? Builder.CreateAnd(Condition, FeatureCond) : FeatureCond;
|
|
}
|
|
return Condition;
|
|
}
|
|
|
|
static void CreateMultiVersionResolverReturn(CodeGenModule &CGM,
|
|
llvm::Function *Resolver,
|
|
CGBuilderTy &Builder,
|
|
llvm::Function *FuncToReturn,
|
|
bool SupportsIFunc) {
|
|
if (SupportsIFunc) {
|
|
Builder.CreateRet(FuncToReturn);
|
|
return;
|
|
}
|
|
|
|
llvm::SmallVector<llvm::Value *, 10> Args;
|
|
llvm::for_each(Resolver->args(),
|
|
[&](llvm::Argument &Arg) { Args.push_back(&Arg); });
|
|
|
|
llvm::CallInst *Result = Builder.CreateCall(FuncToReturn, Args);
|
|
Result->setTailCallKind(llvm::CallInst::TCK_MustTail);
|
|
|
|
if (Resolver->getReturnType()->isVoidTy())
|
|
Builder.CreateRetVoid();
|
|
else
|
|
Builder.CreateRet(Result);
|
|
}
|
|
|
|
void CodeGenFunction::EmitMultiVersionResolver(
|
|
llvm::Function *Resolver, ArrayRef<MultiVersionResolverOption> Options) {
|
|
assert(getContext().getTargetInfo().getTriple().isX86() &&
|
|
"Only implemented for x86 targets");
|
|
|
|
bool SupportsIFunc = getContext().getTargetInfo().supportsIFunc();
|
|
|
|
// Main function's basic block.
|
|
llvm::BasicBlock *CurBlock = createBasicBlock("resolver_entry", Resolver);
|
|
Builder.SetInsertPoint(CurBlock);
|
|
EmitX86CpuInit();
|
|
|
|
for (const MultiVersionResolverOption &RO : Options) {
|
|
Builder.SetInsertPoint(CurBlock);
|
|
llvm::Value *Condition = FormResolverCondition(RO);
|
|
|
|
// The 'default' or 'generic' case.
|
|
if (!Condition) {
|
|
assert(&RO == Options.end() - 1 &&
|
|
"Default or Generic case must be last");
|
|
CreateMultiVersionResolverReturn(CGM, Resolver, Builder, RO.Function,
|
|
SupportsIFunc);
|
|
return;
|
|
}
|
|
|
|
llvm::BasicBlock *RetBlock = createBasicBlock("resolver_return", Resolver);
|
|
CGBuilderTy RetBuilder(*this, RetBlock);
|
|
CreateMultiVersionResolverReturn(CGM, Resolver, RetBuilder, RO.Function,
|
|
SupportsIFunc);
|
|
CurBlock = createBasicBlock("resolver_else", Resolver);
|
|
Builder.CreateCondBr(Condition, RetBlock, CurBlock);
|
|
}
|
|
|
|
// If no generic/default, emit an unreachable.
|
|
Builder.SetInsertPoint(CurBlock);
|
|
llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
|
|
TrapCall->setDoesNotReturn();
|
|
TrapCall->setDoesNotThrow();
|
|
Builder.CreateUnreachable();
|
|
Builder.ClearInsertionPoint();
|
|
}
|
|
|
|
// Loc - where the diagnostic will point, where in the source code this
|
|
// alignment has failed.
|
|
// SecondaryLoc - if present (will be present if sufficiently different from
|
|
// Loc), the diagnostic will additionally point a "Note:" to this location.
|
|
// It should be the location where the __attribute__((assume_aligned))
|
|
// was written e.g.
|
|
void CodeGenFunction::emitAlignmentAssumptionCheck(
|
|
llvm::Value *Ptr, QualType Ty, SourceLocation Loc,
|
|
SourceLocation SecondaryLoc, llvm::Value *Alignment,
|
|
llvm::Value *OffsetValue, llvm::Value *TheCheck,
|
|
llvm::Instruction *Assumption) {
|
|
assert(Assumption && isa<llvm::CallInst>(Assumption) &&
|
|
cast<llvm::CallInst>(Assumption)->getCalledOperand() ==
|
|
llvm::Intrinsic::getDeclaration(
|
|
Builder.GetInsertBlock()->getParent()->getParent(),
|
|
llvm::Intrinsic::assume) &&
|
|
"Assumption should be a call to llvm.assume().");
|
|
assert(&(Builder.GetInsertBlock()->back()) == Assumption &&
|
|
"Assumption should be the last instruction of the basic block, "
|
|
"since the basic block is still being generated.");
|
|
|
|
if (!SanOpts.has(SanitizerKind::Alignment))
|
|
return;
|
|
|
|
// Don't check pointers to volatile data. The behavior here is implementation-
|
|
// defined.
|
|
if (Ty->getPointeeType().isVolatileQualified())
|
|
return;
|
|
|
|
// We need to temorairly remove the assumption so we can insert the
|
|
// sanitizer check before it, else the check will be dropped by optimizations.
|
|
Assumption->removeFromParent();
|
|
|
|
{
|
|
SanitizerScope SanScope(this);
|
|
|
|
if (!OffsetValue)
|
|
OffsetValue = Builder.getInt1(false); // no offset.
|
|
|
|
llvm::Constant *StaticData[] = {EmitCheckSourceLocation(Loc),
|
|
EmitCheckSourceLocation(SecondaryLoc),
|
|
EmitCheckTypeDescriptor(Ty)};
|
|
llvm::Value *DynamicData[] = {EmitCheckValue(Ptr),
|
|
EmitCheckValue(Alignment),
|
|
EmitCheckValue(OffsetValue)};
|
|
EmitCheck({std::make_pair(TheCheck, SanitizerKind::Alignment)},
|
|
SanitizerHandler::AlignmentAssumption, StaticData, DynamicData);
|
|
}
|
|
|
|
// We are now in the (new, empty) "cont" basic block.
|
|
// Reintroduce the assumption.
|
|
Builder.Insert(Assumption);
|
|
// FIXME: Assumption still has it's original basic block as it's Parent.
|
|
}
|
|
|
|
llvm::DebugLoc CodeGenFunction::SourceLocToDebugLoc(SourceLocation Location) {
|
|
if (CGDebugInfo *DI = getDebugInfo())
|
|
return DI->SourceLocToDebugLoc(Location);
|
|
|
|
return llvm::DebugLoc();
|
|
}
|
|
|
|
llvm::Value *
|
|
CodeGenFunction::emitCondLikelihoodViaExpectIntrinsic(llvm::Value *Cond,
|
|
Stmt::Likelihood LH) {
|
|
switch (LH) {
|
|
case Stmt::LH_None:
|
|
return Cond;
|
|
case Stmt::LH_Likely:
|
|
case Stmt::LH_Unlikely:
|
|
// Don't generate llvm.expect on -O0 as the backend won't use it for
|
|
// anything.
|
|
if (CGM.getCodeGenOpts().OptimizationLevel == 0)
|
|
return Cond;
|
|
llvm::Type *CondTy = Cond->getType();
|
|
assert(CondTy->isIntegerTy(1) && "expecting condition to be a boolean");
|
|
llvm::Function *FnExpect =
|
|
CGM.getIntrinsic(llvm::Intrinsic::expect, CondTy);
|
|
llvm::Value *ExpectedValueOfCond =
|
|
llvm::ConstantInt::getBool(CondTy, LH == Stmt::LH_Likely);
|
|
return Builder.CreateCall(FnExpect, {Cond, ExpectedValueOfCond},
|
|
Cond->getName() + ".expval");
|
|
}
|
|
llvm_unreachable("Unknown Likelihood");
|
|
}
|