llvm-6502/lib/Analysis/TargetTransformInfo.cpp
David Peixotto ea468dddfe Ignore annotation function calls in cost computation
The annotation instructions are dropped during codegen and have no
impact on size.  In some cases, the annotations were preventing the
unroller from unrolling a loop because the annotation calls were
pushing the cost over the unrolling threshold.

Differential Revision: http://reviews.llvm.org/D5335



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218525 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-26 17:48:40 +00:00

641 lines
21 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/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/Operator.h"
#include "llvm/Support/ErrorHandling.h"
using namespace llvm;
#define DEBUG_TYPE "tti"
// Setup the analysis group to manage the TargetTransformInfo passes.
INITIALIZE_ANALYSIS_GROUP(TargetTransformInfo, "Target Information", NoTTI)
char TargetTransformInfo::ID = 0;
TargetTransformInfo::~TargetTransformInfo() {
}
void TargetTransformInfo::pushTTIStack(Pass *P) {
TopTTI = this;
PrevTTI = &P->getAnalysis<TargetTransformInfo>();
// Walk up the chain and update the top TTI pointer.
for (TargetTransformInfo *PTTI = PrevTTI; PTTI; PTTI = PTTI->PrevTTI)
PTTI->TopTTI = this;
}
void TargetTransformInfo::getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<TargetTransformInfo>();
}
unsigned TargetTransformInfo::getOperationCost(unsigned Opcode, Type *Ty,
Type *OpTy) const {
return PrevTTI->getOperationCost(Opcode, Ty, OpTy);
}
unsigned TargetTransformInfo::getGEPCost(
const Value *Ptr, ArrayRef<const Value *> Operands) const {
return PrevTTI->getGEPCost(Ptr, Operands);
}
unsigned TargetTransformInfo::getCallCost(FunctionType *FTy,
int NumArgs) const {
return PrevTTI->getCallCost(FTy, NumArgs);
}
unsigned TargetTransformInfo::getCallCost(const Function *F,
int NumArgs) const {
return PrevTTI->getCallCost(F, NumArgs);
}
unsigned TargetTransformInfo::getCallCost(
const Function *F, ArrayRef<const Value *> Arguments) const {
return PrevTTI->getCallCost(F, Arguments);
}
unsigned TargetTransformInfo::getIntrinsicCost(
Intrinsic::ID IID, Type *RetTy, ArrayRef<Type *> ParamTys) const {
return PrevTTI->getIntrinsicCost(IID, RetTy, ParamTys);
}
unsigned TargetTransformInfo::getIntrinsicCost(
Intrinsic::ID IID, Type *RetTy, ArrayRef<const Value *> Arguments) const {
return PrevTTI->getIntrinsicCost(IID, RetTy, Arguments);
}
unsigned TargetTransformInfo::getUserCost(const User *U) const {
return PrevTTI->getUserCost(U);
}
bool TargetTransformInfo::hasBranchDivergence() const {
return PrevTTI->hasBranchDivergence();
}
bool TargetTransformInfo::isLoweredToCall(const Function *F) const {
return PrevTTI->isLoweredToCall(F);
}
void
TargetTransformInfo::getUnrollingPreferences(const Function *F, Loop *L,
UnrollingPreferences &UP) const {
PrevTTI->getUnrollingPreferences(F, L, UP);
}
bool TargetTransformInfo::isLegalAddImmediate(int64_t Imm) const {
return PrevTTI->isLegalAddImmediate(Imm);
}
bool TargetTransformInfo::isLegalICmpImmediate(int64_t Imm) const {
return PrevTTI->isLegalICmpImmediate(Imm);
}
bool TargetTransformInfo::isLegalAddressingMode(Type *Ty, GlobalValue *BaseGV,
int64_t BaseOffset,
bool HasBaseReg,
int64_t Scale) const {
return PrevTTI->isLegalAddressingMode(Ty, BaseGV, BaseOffset, HasBaseReg,
Scale);
}
int TargetTransformInfo::getScalingFactorCost(Type *Ty, GlobalValue *BaseGV,
int64_t BaseOffset,
bool HasBaseReg,
int64_t Scale) const {
return PrevTTI->getScalingFactorCost(Ty, BaseGV, BaseOffset, HasBaseReg,
Scale);
}
bool TargetTransformInfo::isTruncateFree(Type *Ty1, Type *Ty2) const {
return PrevTTI->isTruncateFree(Ty1, Ty2);
}
bool TargetTransformInfo::isTypeLegal(Type *Ty) const {
return PrevTTI->isTypeLegal(Ty);
}
unsigned TargetTransformInfo::getJumpBufAlignment() const {
return PrevTTI->getJumpBufAlignment();
}
unsigned TargetTransformInfo::getJumpBufSize() const {
return PrevTTI->getJumpBufSize();
}
bool TargetTransformInfo::shouldBuildLookupTables() const {
return PrevTTI->shouldBuildLookupTables();
}
TargetTransformInfo::PopcntSupportKind
TargetTransformInfo::getPopcntSupport(unsigned IntTyWidthInBit) const {
return PrevTTI->getPopcntSupport(IntTyWidthInBit);
}
bool TargetTransformInfo::haveFastSqrt(Type *Ty) const {
return PrevTTI->haveFastSqrt(Ty);
}
unsigned TargetTransformInfo::getIntImmCost(const APInt &Imm, Type *Ty) const {
return PrevTTI->getIntImmCost(Imm, Ty);
}
unsigned TargetTransformInfo::getIntImmCost(unsigned Opc, unsigned Idx,
const APInt &Imm, Type *Ty) const {
return PrevTTI->getIntImmCost(Opc, Idx, Imm, Ty);
}
unsigned TargetTransformInfo::getIntImmCost(Intrinsic::ID IID, unsigned Idx,
const APInt &Imm, Type *Ty) const {
return PrevTTI->getIntImmCost(IID, Idx, Imm, Ty);
}
unsigned TargetTransformInfo::getNumberOfRegisters(bool Vector) const {
return PrevTTI->getNumberOfRegisters(Vector);
}
unsigned TargetTransformInfo::getRegisterBitWidth(bool Vector) const {
return PrevTTI->getRegisterBitWidth(Vector);
}
unsigned TargetTransformInfo::getMaxInterleaveFactor() const {
return PrevTTI->getMaxInterleaveFactor();
}
unsigned TargetTransformInfo::getArithmeticInstrCost(
unsigned Opcode, Type *Ty, OperandValueKind Op1Info,
OperandValueKind Op2Info, OperandValueProperties Opd1PropInfo,
OperandValueProperties Opd2PropInfo) const {
return PrevTTI->getArithmeticInstrCost(Opcode, Ty, Op1Info, Op2Info,
Opd1PropInfo, Opd2PropInfo);
}
unsigned TargetTransformInfo::getShuffleCost(ShuffleKind Kind, Type *Tp,
int Index, Type *SubTp) const {
return PrevTTI->getShuffleCost(Kind, Tp, Index, SubTp);
}
unsigned TargetTransformInfo::getCastInstrCost(unsigned Opcode, Type *Dst,
Type *Src) const {
return PrevTTI->getCastInstrCost(Opcode, Dst, Src);
}
unsigned TargetTransformInfo::getCFInstrCost(unsigned Opcode) const {
return PrevTTI->getCFInstrCost(Opcode);
}
unsigned TargetTransformInfo::getCmpSelInstrCost(unsigned Opcode, Type *ValTy,
Type *CondTy) const {
return PrevTTI->getCmpSelInstrCost(Opcode, ValTy, CondTy);
}
unsigned TargetTransformInfo::getVectorInstrCost(unsigned Opcode, Type *Val,
unsigned Index) const {
return PrevTTI->getVectorInstrCost(Opcode, Val, Index);
}
unsigned TargetTransformInfo::getMemoryOpCost(unsigned Opcode, Type *Src,
unsigned Alignment,
unsigned AddressSpace) const {
return PrevTTI->getMemoryOpCost(Opcode, Src, Alignment, AddressSpace);
;
}
unsigned
TargetTransformInfo::getIntrinsicInstrCost(Intrinsic::ID ID,
Type *RetTy,
ArrayRef<Type *> Tys) const {
return PrevTTI->getIntrinsicInstrCost(ID, RetTy, Tys);
}
unsigned TargetTransformInfo::getNumberOfParts(Type *Tp) const {
return PrevTTI->getNumberOfParts(Tp);
}
unsigned TargetTransformInfo::getAddressComputationCost(Type *Tp,
bool IsComplex) const {
return PrevTTI->getAddressComputationCost(Tp, IsComplex);
}
unsigned TargetTransformInfo::getReductionCost(unsigned Opcode, Type *Ty,
bool IsPairwise) const {
return PrevTTI->getReductionCost(Opcode, Ty, IsPairwise);
}
unsigned TargetTransformInfo::getCostOfKeepingLiveOverCall(ArrayRef<Type*> Tys)
const {
return PrevTTI->getCostOfKeepingLiveOverCall(Tys);
}
namespace {
struct NoTTI final : ImmutablePass, TargetTransformInfo {
const DataLayout *DL;
NoTTI() : ImmutablePass(ID), DL(nullptr) {
initializeNoTTIPass(*PassRegistry::getPassRegistry());
}
void initializePass() override {
// Note that this subclass is special, and must *not* call initializeTTI as
// it does not chain.
TopTTI = this;
PrevTTI = nullptr;
DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
DL = DLP ? &DLP->getDataLayout() : nullptr;
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
// Note that this subclass is special, and must *not* call
// TTI::getAnalysisUsage as it breaks the recursion.
}
/// Pass identification.
static char ID;
/// Provide necessary pointer adjustments for the two base classes.
void *getAdjustedAnalysisPointer(const void *ID) override {
if (ID == &TargetTransformInfo::ID)
return (TargetTransformInfo*)this;
return this;
}
unsigned getOperationCost(unsigned Opcode, Type *Ty,
Type *OpTy) const override {
switch (Opcode) {
default:
// By default, just classify everything as 'basic'.
return TCC_Basic;
case Instruction::GetElementPtr:
llvm_unreachable("Use getGEPCost for GEP operations!");
case Instruction::BitCast:
assert(OpTy && "Cast instructions must provide the operand type");
if (Ty == OpTy || (Ty->isPointerTy() && OpTy->isPointerTy()))
// Identity and pointer-to-pointer casts are free.
return TCC_Free;
// Otherwise, the default basic cost is used.
return TCC_Basic;
case Instruction::IntToPtr: {
if (!DL)
return TCC_Basic;
// An inttoptr cast is free so long as the input is a legal integer type
// which doesn't contain values outside the range of a pointer.
unsigned OpSize = OpTy->getScalarSizeInBits();
if (DL->isLegalInteger(OpSize) &&
OpSize <= DL->getPointerTypeSizeInBits(Ty))
return TCC_Free;
// Otherwise it's not a no-op.
return TCC_Basic;
}
case Instruction::PtrToInt: {
if (!DL)
return TCC_Basic;
// A ptrtoint cast is free so long as the result is large enough to store
// the pointer, and a legal integer type.
unsigned DestSize = Ty->getScalarSizeInBits();
if (DL->isLegalInteger(DestSize) &&
DestSize >= DL->getPointerTypeSizeInBits(OpTy))
return TCC_Free;
// Otherwise it's not a no-op.
return TCC_Basic;
}
case Instruction::Trunc:
// trunc to a native type is free (assuming the target has compare and
// shift-right of the same width).
if (DL && DL->isLegalInteger(DL->getTypeSizeInBits(Ty)))
return TCC_Free;
return TCC_Basic;
}
}
unsigned getGEPCost(const Value *Ptr,
ArrayRef<const Value *> Operands) const override {
// In the basic model, we just assume that all-constant GEPs will be folded
// into their uses via addressing modes.
for (unsigned Idx = 0, Size = Operands.size(); Idx != Size; ++Idx)
if (!isa<Constant>(Operands[Idx]))
return TCC_Basic;
return TCC_Free;
}
unsigned getCallCost(FunctionType *FTy, int NumArgs = -1) const override
{
assert(FTy && "FunctionType must be provided to this routine.");
// The target-independent implementation just measures the size of the
// function by approximating that each argument will take on average one
// instruction to prepare.
if (NumArgs < 0)
// Set the argument number to the number of explicit arguments in the
// function.
NumArgs = FTy->getNumParams();
return TCC_Basic * (NumArgs + 1);
}
unsigned getCallCost(const Function *F, int NumArgs = -1) const override
{
assert(F && "A concrete function must be provided to this routine.");
if (NumArgs < 0)
// Set the argument number to the number of explicit arguments in the
// function.
NumArgs = F->arg_size();
if (Intrinsic::ID IID = (Intrinsic::ID)F->getIntrinsicID()) {
FunctionType *FTy = F->getFunctionType();
SmallVector<Type *, 8> ParamTys(FTy->param_begin(), FTy->param_end());
return TopTTI->getIntrinsicCost(IID, FTy->getReturnType(), ParamTys);
}
if (!TopTTI->isLoweredToCall(F))
return TCC_Basic; // Give a basic cost if it will be lowered directly.
return TopTTI->getCallCost(F->getFunctionType(), NumArgs);
}
unsigned getCallCost(const Function *F,
ArrayRef<const Value *> Arguments) const override {
// Simply delegate to generic handling of the call.
// FIXME: We should use instsimplify or something else to catch calls which
// will constant fold with these arguments.
return TopTTI->getCallCost(F, Arguments.size());
}
unsigned getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
ArrayRef<Type *> ParamTys) const override {
switch (IID) {
default:
// Intrinsics rarely (if ever) have normal argument setup constraints.
// Model them as having a basic instruction cost.
// FIXME: This is wrong for libc intrinsics.
return TCC_Basic;
case Intrinsic::annotation:
case Intrinsic::assume:
case Intrinsic::dbg_declare:
case Intrinsic::dbg_value:
case Intrinsic::invariant_start:
case Intrinsic::invariant_end:
case Intrinsic::lifetime_start:
case Intrinsic::lifetime_end:
case Intrinsic::objectsize:
case Intrinsic::ptr_annotation:
case Intrinsic::var_annotation:
// These intrinsics don't actually represent code after lowering.
return TCC_Free;
}
}
unsigned
getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
ArrayRef<const Value *> Arguments) const override {
// Delegate to the generic intrinsic handling code. This mostly provides an
// opportunity for targets to (for example) special case the cost of
// certain intrinsics based on constants used as arguments.
SmallVector<Type *, 8> ParamTys;
ParamTys.reserve(Arguments.size());
for (unsigned Idx = 0, Size = Arguments.size(); Idx != Size; ++Idx)
ParamTys.push_back(Arguments[Idx]->getType());
return TopTTI->getIntrinsicCost(IID, RetTy, ParamTys);
}
unsigned getUserCost(const User *U) const override {
if (isa<PHINode>(U))
return TCC_Free; // Model all PHI nodes as free.
if (const GEPOperator *GEP = dyn_cast<GEPOperator>(U)) {
SmallVector<const Value *, 4> Indices(GEP->idx_begin(), GEP->idx_end());
return TopTTI->getGEPCost(GEP->getPointerOperand(), Indices);
}
if (ImmutableCallSite CS = U) {
const Function *F = CS.getCalledFunction();
if (!F) {
// Just use the called value type.
Type *FTy = CS.getCalledValue()->getType()->getPointerElementType();
return TopTTI->getCallCost(cast<FunctionType>(FTy), CS.arg_size());
}
SmallVector<const Value *, 8> Arguments(CS.arg_begin(), CS.arg_end());
return TopTTI->getCallCost(F, Arguments);
}
if (const CastInst *CI = dyn_cast<CastInst>(U)) {
// Result of a cmp instruction is often extended (to be used by other
// cmp instructions, logical or return instructions). These are usually
// nop on most sane targets.
if (isa<CmpInst>(CI->getOperand(0)))
return TCC_Free;
}
// Otherwise delegate to the fully generic implementations.
return getOperationCost(Operator::getOpcode(U), U->getType(),
U->getNumOperands() == 1 ?
U->getOperand(0)->getType() : nullptr);
}
bool hasBranchDivergence() const override { return false; }
bool isLoweredToCall(const Function *F) const override {
// FIXME: These should almost certainly not be handled here, and instead
// handled with the help of TLI or the target itself. This was largely
// ported from existing analysis heuristics here so that such refactorings
// can take place in the future.
if (F->isIntrinsic())
return false;
if (F->hasLocalLinkage() || !F->hasName())
return true;
StringRef Name = F->getName();
// These will all likely lower to a single selection DAG node.
if (Name == "copysign" || Name == "copysignf" || Name == "copysignl" ||
Name == "fabs" || Name == "fabsf" || Name == "fabsl" || Name == "sin" ||
Name == "sinf" || Name == "sinl" || Name == "cos" || Name == "cosf" ||
Name == "cosl" || Name == "sqrt" || Name == "sqrtf" || Name == "sqrtl")
return false;
// These are all likely to be optimized into something smaller.
if (Name == "pow" || Name == "powf" || Name == "powl" || Name == "exp2" ||
Name == "exp2l" || Name == "exp2f" || Name == "floor" || Name ==
"floorf" || Name == "ceil" || Name == "round" || Name == "ffs" ||
Name == "ffsl" || Name == "abs" || Name == "labs" || Name == "llabs")
return false;
return true;
}
void getUnrollingPreferences(const Function *, Loop *,
UnrollingPreferences &) const override {}
bool isLegalAddImmediate(int64_t Imm) const override {
return false;
}
bool isLegalICmpImmediate(int64_t Imm) const override {
return false;
}
bool isLegalAddressingMode(Type *Ty, GlobalValue *BaseGV, int64_t BaseOffset,
bool HasBaseReg, int64_t Scale) const override
{
// Guess that reg+reg addressing is allowed. This heuristic is taken from
// the implementation of LSR.
return !BaseGV && BaseOffset == 0 && Scale <= 1;
}
int getScalingFactorCost(Type *Ty, GlobalValue *BaseGV, int64_t BaseOffset,
bool HasBaseReg, int64_t Scale) const override {
// Guess that all legal addressing mode are free.
if(isLegalAddressingMode(Ty, BaseGV, BaseOffset, HasBaseReg, Scale))
return 0;
return -1;
}
bool isTruncateFree(Type *Ty1, Type *Ty2) const override {
return false;
}
bool isTypeLegal(Type *Ty) const override {
return false;
}
unsigned getJumpBufAlignment() const override {
return 0;
}
unsigned getJumpBufSize() const override {
return 0;
}
bool shouldBuildLookupTables() const override {
return true;
}
PopcntSupportKind
getPopcntSupport(unsigned IntTyWidthInBit) const override {
return PSK_Software;
}
bool haveFastSqrt(Type *Ty) const override {
return false;
}
unsigned getIntImmCost(const APInt &Imm, Type *Ty) const override {
return TCC_Basic;
}
unsigned getIntImmCost(unsigned Opcode, unsigned Idx, const APInt &Imm,
Type *Ty) const override {
return TCC_Free;
}
unsigned getIntImmCost(Intrinsic::ID IID, unsigned Idx, const APInt &Imm,
Type *Ty) const override {
return TCC_Free;
}
unsigned getNumberOfRegisters(bool Vector) const override {
return 8;
}
unsigned getRegisterBitWidth(bool Vector) const override {
return 32;
}
unsigned getMaxInterleaveFactor() const override {
return 1;
}
unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty, OperandValueKind,
OperandValueKind, OperandValueProperties,
OperandValueProperties) const override {
return 1;
}
unsigned getShuffleCost(ShuffleKind Kind, Type *Ty,
int Index = 0, Type *SubTp = nullptr) const override {
return 1;
}
unsigned getCastInstrCost(unsigned Opcode, Type *Dst,
Type *Src) const override {
return 1;
}
unsigned getCFInstrCost(unsigned Opcode) const override {
return 1;
}
unsigned getCmpSelInstrCost(unsigned Opcode, Type *ValTy,
Type *CondTy = nullptr) const override {
return 1;
}
unsigned getVectorInstrCost(unsigned Opcode, Type *Val,
unsigned Index = -1) const override {
return 1;
}
unsigned getMemoryOpCost(unsigned Opcode, Type *Src, unsigned Alignment,
unsigned AddressSpace) const override {
return 1;
}
unsigned getIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy,
ArrayRef<Type*> Tys) const override {
return 1;
}
unsigned getNumberOfParts(Type *Tp) const override {
return 0;
}
unsigned getAddressComputationCost(Type *Tp, bool) const override {
return 0;
}
unsigned getReductionCost(unsigned, Type *, bool) const override {
return 1;
}
unsigned getCostOfKeepingLiveOverCall(ArrayRef<Type*> Tys) const override {
return 0;
}
};
} // end anonymous namespace
INITIALIZE_AG_PASS(NoTTI, TargetTransformInfo, "notti",
"No target information", true, true, true)
char NoTTI::ID = 0;
ImmutablePass *llvm::createNoTargetTransformInfoPass() {
return new NoTTI();
}