llvm-mirror/lib/Analysis/TargetTransformInfo.cpp
Charles Davis 24439f8d33 [X86] Support the "ms-hotpatch" attribute.
Summary:
Based on two patches by Michael Mueller.

This is a target attribute that causes a function marked with it to be
emitted as "hotpatchable". This particular mechanism was originally
devised by Microsoft for patching their binaries (which they are
constantly updating to stay ahead of crackers, script kiddies, and other
ne'er-do-wells on the Internet), but is now commonly abused by Windows
programs to hook API functions.

This mechanism is target-specific. For x86, a two-byte no-op instruction
is emitted at the function's entry point; the entry point must be
immediately preceded by 64 (32-bit) or 128 (64-bit) bytes of padding.
This padding is where the patch code is written. The two byte no-op is
then overwritten with a short jump into this code. The no-op is usually
a `movl %edi, %edi` instruction; this is used as a magic value
indicating that this is a hotpatchable function.

Reviewers: majnemer, sanjoy, rnk

Subscribers: dberris, llvm-commits

Differential Revision: https://reviews.llvm.org/D19908

llvm-svn: 278048
2016-08-08 21:01:39 +00:00

476 lines
17 KiB
C++

//===- llvm/Analysis/TargetTransformInfo.cpp ------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Analysis/TargetTransformInfoImpl.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/Support/ErrorHandling.h"
#include <utility>
using namespace llvm;
#define DEBUG_TYPE "tti"
namespace {
/// \brief No-op implementation of the TTI interface using the utility base
/// classes.
///
/// This is used when no target specific information is available.
struct NoTTIImpl : TargetTransformInfoImplCRTPBase<NoTTIImpl> {
explicit NoTTIImpl(const DataLayout &DL)
: TargetTransformInfoImplCRTPBase<NoTTIImpl>(DL) {}
};
}
TargetTransformInfo::TargetTransformInfo(const DataLayout &DL)
: TTIImpl(new Model<NoTTIImpl>(NoTTIImpl(DL))) {}
TargetTransformInfo::~TargetTransformInfo() {}
TargetTransformInfo::TargetTransformInfo(TargetTransformInfo &&Arg)
: TTIImpl(std::move(Arg.TTIImpl)) {}
TargetTransformInfo &TargetTransformInfo::operator=(TargetTransformInfo &&RHS) {
TTIImpl = std::move(RHS.TTIImpl);
return *this;
}
int TargetTransformInfo::getOperationCost(unsigned Opcode, Type *Ty,
Type *OpTy) const {
int Cost = TTIImpl->getOperationCost(Opcode, Ty, OpTy);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCallCost(FunctionType *FTy, int NumArgs) const {
int Cost = TTIImpl->getCallCost(FTy, NumArgs);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCallCost(const Function *F,
ArrayRef<const Value *> Arguments) const {
int Cost = TTIImpl->getCallCost(F, Arguments);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
unsigned TargetTransformInfo::getInliningThresholdMultiplier() const {
return TTIImpl->getInliningThresholdMultiplier();
}
int TargetTransformInfo::getGEPCost(Type *PointeeType, const Value *Ptr,
ArrayRef<const Value *> Operands) const {
return TTIImpl->getGEPCost(PointeeType, Ptr, Operands);
}
int TargetTransformInfo::getIntrinsicCost(
Intrinsic::ID IID, Type *RetTy, ArrayRef<const Value *> Arguments) const {
int Cost = TTIImpl->getIntrinsicCost(IID, RetTy, Arguments);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getUserCost(const User *U) const {
int Cost = TTIImpl->getUserCost(U);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
bool TargetTransformInfo::hasBranchDivergence() const {
return TTIImpl->hasBranchDivergence();
}
bool TargetTransformInfo::isSourceOfDivergence(const Value *V) const {
return TTIImpl->isSourceOfDivergence(V);
}
bool TargetTransformInfo::isLoweredToCall(const Function *F) const {
return TTIImpl->isLoweredToCall(F);
}
void TargetTransformInfo::getUnrollingPreferences(
Loop *L, UnrollingPreferences &UP) const {
return TTIImpl->getUnrollingPreferences(L, UP);
}
void TargetTransformInfo::emitPatchableOp(
StringRef PatchType, MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MBBI) const {
return TTIImpl->emitPatchableOp(PatchType, MBB, MBBI);
}
bool TargetTransformInfo::isLegalAddImmediate(int64_t Imm) const {
return TTIImpl->isLegalAddImmediate(Imm);
}
bool TargetTransformInfo::isLegalICmpImmediate(int64_t Imm) const {
return TTIImpl->isLegalICmpImmediate(Imm);
}
bool TargetTransformInfo::isLegalAddressingMode(Type *Ty, GlobalValue *BaseGV,
int64_t BaseOffset,
bool HasBaseReg,
int64_t Scale,
unsigned AddrSpace) const {
return TTIImpl->isLegalAddressingMode(Ty, BaseGV, BaseOffset, HasBaseReg,
Scale, AddrSpace);
}
bool TargetTransformInfo::isLegalMaskedStore(Type *DataType) const {
return TTIImpl->isLegalMaskedStore(DataType);
}
bool TargetTransformInfo::isLegalMaskedLoad(Type *DataType) const {
return TTIImpl->isLegalMaskedLoad(DataType);
}
bool TargetTransformInfo::isLegalMaskedGather(Type *DataType) const {
return TTIImpl->isLegalMaskedGather(DataType);
}
bool TargetTransformInfo::isLegalMaskedScatter(Type *DataType) const {
return TTIImpl->isLegalMaskedGather(DataType);
}
int TargetTransformInfo::getScalingFactorCost(Type *Ty, GlobalValue *BaseGV,
int64_t BaseOffset,
bool HasBaseReg,
int64_t Scale,
unsigned AddrSpace) const {
int Cost = TTIImpl->getScalingFactorCost(Ty, BaseGV, BaseOffset, HasBaseReg,
Scale, AddrSpace);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
bool TargetTransformInfo::isTruncateFree(Type *Ty1, Type *Ty2) const {
return TTIImpl->isTruncateFree(Ty1, Ty2);
}
bool TargetTransformInfo::isProfitableToHoist(Instruction *I) const {
return TTIImpl->isProfitableToHoist(I);
}
bool TargetTransformInfo::isTypeLegal(Type *Ty) const {
return TTIImpl->isTypeLegal(Ty);
}
unsigned TargetTransformInfo::getJumpBufAlignment() const {
return TTIImpl->getJumpBufAlignment();
}
unsigned TargetTransformInfo::getJumpBufSize() const {
return TTIImpl->getJumpBufSize();
}
bool TargetTransformInfo::shouldBuildLookupTables() const {
return TTIImpl->shouldBuildLookupTables();
}
bool TargetTransformInfo::enableAggressiveInterleaving(bool LoopHasReductions) const {
return TTIImpl->enableAggressiveInterleaving(LoopHasReductions);
}
bool TargetTransformInfo::enableInterleavedAccessVectorization() const {
return TTIImpl->enableInterleavedAccessVectorization();
}
bool TargetTransformInfo::isFPVectorizationPotentiallyUnsafe() const {
return TTIImpl->isFPVectorizationPotentiallyUnsafe();
}
bool TargetTransformInfo::allowsMisalignedMemoryAccesses(LLVMContext &Context,
unsigned BitWidth,
unsigned AddressSpace,
unsigned Alignment,
bool *Fast) const {
return TTIImpl->allowsMisalignedMemoryAccesses(Context, BitWidth, AddressSpace,
Alignment, Fast);
}
TargetTransformInfo::PopcntSupportKind
TargetTransformInfo::getPopcntSupport(unsigned IntTyWidthInBit) const {
return TTIImpl->getPopcntSupport(IntTyWidthInBit);
}
bool TargetTransformInfo::haveFastSqrt(Type *Ty) const {
return TTIImpl->haveFastSqrt(Ty);
}
int TargetTransformInfo::getFPOpCost(Type *Ty) const {
int Cost = TTIImpl->getFPOpCost(Ty);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntImmCodeSizeCost(unsigned Opcode, unsigned Idx,
const APInt &Imm,
Type *Ty) const {
int Cost = TTIImpl->getIntImmCodeSizeCost(Opcode, Idx, Imm, Ty);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntImmCost(const APInt &Imm, Type *Ty) const {
int Cost = TTIImpl->getIntImmCost(Imm, Ty);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntImmCost(unsigned Opcode, unsigned Idx,
const APInt &Imm, Type *Ty) const {
int Cost = TTIImpl->getIntImmCost(Opcode, Idx, Imm, Ty);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntImmCost(Intrinsic::ID IID, unsigned Idx,
const APInt &Imm, Type *Ty) const {
int Cost = TTIImpl->getIntImmCost(IID, Idx, Imm, Ty);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
unsigned TargetTransformInfo::getNumberOfRegisters(bool Vector) const {
return TTIImpl->getNumberOfRegisters(Vector);
}
unsigned TargetTransformInfo::getRegisterBitWidth(bool Vector) const {
return TTIImpl->getRegisterBitWidth(Vector);
}
unsigned TargetTransformInfo::getLoadStoreVecRegBitWidth(unsigned AS) const {
return TTIImpl->getLoadStoreVecRegBitWidth(AS);
}
unsigned TargetTransformInfo::getCacheLineSize() const {
return TTIImpl->getCacheLineSize();
}
unsigned TargetTransformInfo::getPrefetchDistance() const {
return TTIImpl->getPrefetchDistance();
}
unsigned TargetTransformInfo::getMinPrefetchStride() const {
return TTIImpl->getMinPrefetchStride();
}
unsigned TargetTransformInfo::getMaxPrefetchIterationsAhead() const {
return TTIImpl->getMaxPrefetchIterationsAhead();
}
unsigned TargetTransformInfo::getMaxInterleaveFactor(unsigned VF) const {
return TTIImpl->getMaxInterleaveFactor(VF);
}
int TargetTransformInfo::getArithmeticInstrCost(
unsigned Opcode, Type *Ty, OperandValueKind Opd1Info,
OperandValueKind Opd2Info, OperandValueProperties Opd1PropInfo,
OperandValueProperties Opd2PropInfo) const {
int Cost = TTIImpl->getArithmeticInstrCost(Opcode, Ty, Opd1Info, Opd2Info,
Opd1PropInfo, Opd2PropInfo);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getShuffleCost(ShuffleKind Kind, Type *Ty, int Index,
Type *SubTp) const {
int Cost = TTIImpl->getShuffleCost(Kind, Ty, Index, SubTp);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCastInstrCost(unsigned Opcode, Type *Dst,
Type *Src) const {
int Cost = TTIImpl->getCastInstrCost(Opcode, Dst, Src);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getExtractWithExtendCost(unsigned Opcode, Type *Dst,
VectorType *VecTy,
unsigned Index) const {
int Cost = TTIImpl->getExtractWithExtendCost(Opcode, Dst, VecTy, Index);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCFInstrCost(unsigned Opcode) const {
int Cost = TTIImpl->getCFInstrCost(Opcode);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCmpSelInstrCost(unsigned Opcode, Type *ValTy,
Type *CondTy) const {
int Cost = TTIImpl->getCmpSelInstrCost(Opcode, ValTy, CondTy);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getVectorInstrCost(unsigned Opcode, Type *Val,
unsigned Index) const {
int Cost = TTIImpl->getVectorInstrCost(Opcode, Val, Index);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getMemoryOpCost(unsigned Opcode, Type *Src,
unsigned Alignment,
unsigned AddressSpace) const {
int Cost = TTIImpl->getMemoryOpCost(Opcode, Src, Alignment, AddressSpace);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getMaskedMemoryOpCost(unsigned Opcode, Type *Src,
unsigned Alignment,
unsigned AddressSpace) const {
int Cost =
TTIImpl->getMaskedMemoryOpCost(Opcode, Src, Alignment, AddressSpace);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getGatherScatterOpCost(unsigned Opcode, Type *DataTy,
Value *Ptr, bool VariableMask,
unsigned Alignment) const {
int Cost = TTIImpl->getGatherScatterOpCost(Opcode, DataTy, Ptr, VariableMask,
Alignment);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getInterleavedMemoryOpCost(
unsigned Opcode, Type *VecTy, unsigned Factor, ArrayRef<unsigned> Indices,
unsigned Alignment, unsigned AddressSpace) const {
int Cost = TTIImpl->getInterleavedMemoryOpCost(Opcode, VecTy, Factor, Indices,
Alignment, AddressSpace);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy,
ArrayRef<Type *> Tys,
FastMathFlags FMF) const {
int Cost = TTIImpl->getIntrinsicInstrCost(ID, RetTy, Tys, FMF);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy,
ArrayRef<Value *> Args,
FastMathFlags FMF) const {
int Cost = TTIImpl->getIntrinsicInstrCost(ID, RetTy, Args, FMF);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getCallInstrCost(Function *F, Type *RetTy,
ArrayRef<Type *> Tys) const {
int Cost = TTIImpl->getCallInstrCost(F, RetTy, Tys);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
unsigned TargetTransformInfo::getNumberOfParts(Type *Tp) const {
return TTIImpl->getNumberOfParts(Tp);
}
int TargetTransformInfo::getAddressComputationCost(Type *Tp,
bool IsComplex) const {
int Cost = TTIImpl->getAddressComputationCost(Tp, IsComplex);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
int TargetTransformInfo::getReductionCost(unsigned Opcode, Type *Ty,
bool IsPairwiseForm) const {
int Cost = TTIImpl->getReductionCost(Opcode, Ty, IsPairwiseForm);
assert(Cost >= 0 && "TTI should not produce negative costs!");
return Cost;
}
unsigned
TargetTransformInfo::getCostOfKeepingLiveOverCall(ArrayRef<Type *> Tys) const {
return TTIImpl->getCostOfKeepingLiveOverCall(Tys);
}
bool TargetTransformInfo::getTgtMemIntrinsic(IntrinsicInst *Inst,
MemIntrinsicInfo &Info) const {
return TTIImpl->getTgtMemIntrinsic(Inst, Info);
}
Value *TargetTransformInfo::getOrCreateResultFromMemIntrinsic(
IntrinsicInst *Inst, Type *ExpectedType) const {
return TTIImpl->getOrCreateResultFromMemIntrinsic(Inst, ExpectedType);
}
bool TargetTransformInfo::areInlineCompatible(const Function *Caller,
const Function *Callee) const {
return TTIImpl->areInlineCompatible(Caller, Callee);
}
TargetTransformInfo::Concept::~Concept() {}
TargetIRAnalysis::TargetIRAnalysis() : TTICallback(&getDefaultTTI) {}
TargetIRAnalysis::TargetIRAnalysis(
std::function<Result(const Function &)> TTICallback)
: TTICallback(std::move(TTICallback)) {}
TargetIRAnalysis::Result TargetIRAnalysis::run(const Function &F,
AnalysisManager<Function> &) {
return TTICallback(F);
}
char TargetIRAnalysis::PassID;
TargetIRAnalysis::Result TargetIRAnalysis::getDefaultTTI(const Function &F) {
return Result(F.getParent()->getDataLayout());
}
// Register the basic pass.
INITIALIZE_PASS(TargetTransformInfoWrapperPass, "tti",
"Target Transform Information", false, true)
char TargetTransformInfoWrapperPass::ID = 0;
void TargetTransformInfoWrapperPass::anchor() {}
TargetTransformInfoWrapperPass::TargetTransformInfoWrapperPass()
: ImmutablePass(ID) {
initializeTargetTransformInfoWrapperPassPass(
*PassRegistry::getPassRegistry());
}
TargetTransformInfoWrapperPass::TargetTransformInfoWrapperPass(
TargetIRAnalysis TIRA)
: ImmutablePass(ID), TIRA(std::move(TIRA)) {
initializeTargetTransformInfoWrapperPassPass(
*PassRegistry::getPassRegistry());
}
TargetTransformInfo &TargetTransformInfoWrapperPass::getTTI(const Function &F) {
AnalysisManager<Function> DummyFAM;
TTI = TIRA.run(F, DummyFAM);
return *TTI;
}
ImmutablePass *
llvm::createTargetTransformInfoWrapperPass(TargetIRAnalysis TIRA) {
return new TargetTransformInfoWrapperPass(std::move(TIRA));
}