1 //===- llvm/Analysis/TargetTransformInfo.cpp ------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #define DEBUG_TYPE "tti"
11 #include "llvm/Analysis/TargetTransformInfo.h"
12 #include "llvm/IR/DataLayout.h"
13 #include "llvm/IR/Operator.h"
14 #include "llvm/IR/Instruction.h"
15 #include "llvm/IR/IntrinsicInst.h"
16 #include "llvm/IR/Instructions.h"
17 #include "llvm/Support/CallSite.h"
18 #include "llvm/Support/ErrorHandling.h"
22 // Setup the analysis group to manage the TargetTransformInfo passes.
23 INITIALIZE_ANALYSIS_GROUP(TargetTransformInfo, "Target Information", NoTTI)
24 char TargetTransformInfo::ID = 0;
26 TargetTransformInfo::~TargetTransformInfo() {
29 void TargetTransformInfo::pushTTIStack(Pass *P) {
31 PrevTTI = &P->getAnalysis<TargetTransformInfo>();
33 // Walk up the chain and update the top TTI pointer.
34 for (TargetTransformInfo *PTTI = PrevTTI; PTTI; PTTI = PTTI->PrevTTI)
38 void TargetTransformInfo::popTTIStack() {
41 // Walk up the chain and update the top TTI pointer.
42 for (TargetTransformInfo *PTTI = PrevTTI; PTTI; PTTI = PTTI->PrevTTI)
43 PTTI->TopTTI = PrevTTI;
48 void TargetTransformInfo::getAnalysisUsage(AnalysisUsage &AU) const {
49 AU.addRequired<TargetTransformInfo>();
52 unsigned TargetTransformInfo::getOperationCost(unsigned Opcode, Type *Ty,
54 return PrevTTI->getOperationCost(Opcode, Ty, OpTy);
57 unsigned TargetTransformInfo::getGEPCost(
58 const Value *Ptr, ArrayRef<const Value *> Operands) const {
59 return PrevTTI->getGEPCost(Ptr, Operands);
62 unsigned TargetTransformInfo::getCallCost(FunctionType *FTy,
64 return PrevTTI->getCallCost(FTy, NumArgs);
67 unsigned TargetTransformInfo::getCallCost(const Function *F,
69 return PrevTTI->getCallCost(F, NumArgs);
72 unsigned TargetTransformInfo::getCallCost(
73 const Function *F, ArrayRef<const Value *> Arguments) const {
74 return PrevTTI->getCallCost(F, Arguments);
77 unsigned TargetTransformInfo::getIntrinsicCost(
78 Intrinsic::ID IID, Type *RetTy, ArrayRef<Type *> ParamTys) const {
79 return PrevTTI->getIntrinsicCost(IID, RetTy, ParamTys);
82 unsigned TargetTransformInfo::getIntrinsicCost(
83 Intrinsic::ID IID, Type *RetTy, ArrayRef<const Value *> Arguments) const {
84 return PrevTTI->getIntrinsicCost(IID, RetTy, Arguments);
87 unsigned TargetTransformInfo::getUserCost(const User *U) const {
88 return PrevTTI->getUserCost(U);
91 bool TargetTransformInfo::isLoweredToCall(const Function *F) const {
92 return PrevTTI->isLoweredToCall(F);
95 bool TargetTransformInfo::isLegalAddImmediate(int64_t Imm) const {
96 return PrevTTI->isLegalAddImmediate(Imm);
99 bool TargetTransformInfo::isLegalICmpImmediate(int64_t Imm) const {
100 return PrevTTI->isLegalICmpImmediate(Imm);
103 bool TargetTransformInfo::isLegalAddressingMode(Type *Ty, GlobalValue *BaseGV,
106 int64_t Scale) const {
107 return PrevTTI->isLegalAddressingMode(Ty, BaseGV, BaseOffset, HasBaseReg,
111 bool TargetTransformInfo::isTruncateFree(Type *Ty1, Type *Ty2) const {
112 return PrevTTI->isTruncateFree(Ty1, Ty2);
115 bool TargetTransformInfo::isTypeLegal(Type *Ty) const {
116 return PrevTTI->isTypeLegal(Ty);
119 unsigned TargetTransformInfo::getJumpBufAlignment() const {
120 return PrevTTI->getJumpBufAlignment();
123 unsigned TargetTransformInfo::getJumpBufSize() const {
124 return PrevTTI->getJumpBufSize();
127 bool TargetTransformInfo::shouldBuildLookupTables() const {
128 return PrevTTI->shouldBuildLookupTables();
131 TargetTransformInfo::PopcntSupportKind
132 TargetTransformInfo::getPopcntSupport(unsigned IntTyWidthInBit) const {
133 return PrevTTI->getPopcntSupport(IntTyWidthInBit);
136 unsigned TargetTransformInfo::getIntImmCost(const APInt &Imm, Type *Ty) const {
137 return PrevTTI->getIntImmCost(Imm, Ty);
140 unsigned TargetTransformInfo::getNumberOfRegisters(bool Vector) const {
141 return PrevTTI->getNumberOfRegisters(Vector);
144 unsigned TargetTransformInfo::getRegisterBitWidth(bool Vector) const {
145 return PrevTTI->getRegisterBitWidth(Vector);
148 unsigned TargetTransformInfo::getMaximumUnrollFactor() const {
149 return PrevTTI->getMaximumUnrollFactor();
152 unsigned TargetTransformInfo::getArithmeticInstrCost(unsigned Opcode,
154 return PrevTTI->getArithmeticInstrCost(Opcode, Ty);
157 unsigned TargetTransformInfo::getShuffleCost(ShuffleKind Kind, Type *Tp,
158 int Index, Type *SubTp) const {
159 return PrevTTI->getShuffleCost(Kind, Tp, Index, SubTp);
162 unsigned TargetTransformInfo::getCastInstrCost(unsigned Opcode, Type *Dst,
164 return PrevTTI->getCastInstrCost(Opcode, Dst, Src);
167 unsigned TargetTransformInfo::getCFInstrCost(unsigned Opcode) const {
168 return PrevTTI->getCFInstrCost(Opcode);
171 unsigned TargetTransformInfo::getCmpSelInstrCost(unsigned Opcode, Type *ValTy,
172 Type *CondTy) const {
173 return PrevTTI->getCmpSelInstrCost(Opcode, ValTy, CondTy);
176 unsigned TargetTransformInfo::getVectorInstrCost(unsigned Opcode, Type *Val,
177 unsigned Index) const {
178 return PrevTTI->getVectorInstrCost(Opcode, Val, Index);
181 unsigned TargetTransformInfo::getMemoryOpCost(unsigned Opcode, Type *Src,
183 unsigned AddressSpace) const {
184 return PrevTTI->getMemoryOpCost(Opcode, Src, Alignment, AddressSpace);
189 TargetTransformInfo::getIntrinsicInstrCost(Intrinsic::ID ID,
191 ArrayRef<Type *> Tys) const {
192 return PrevTTI->getIntrinsicInstrCost(ID, RetTy, Tys);
195 unsigned TargetTransformInfo::getNumberOfParts(Type *Tp) const {
196 return PrevTTI->getNumberOfParts(Tp);
202 struct NoTTI : ImmutablePass, TargetTransformInfo {
203 const DataLayout *DL;
205 NoTTI() : ImmutablePass(ID), DL(0) {
206 initializeNoTTIPass(*PassRegistry::getPassRegistry());
209 virtual void initializePass() {
210 // Note that this subclass is special, and must *not* call initializeTTI as
211 // it does not chain.
214 DL = getAnalysisIfAvailable<DataLayout>();
217 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
218 // Note that this subclass is special, and must *not* call
219 // TTI::getAnalysisUsage as it breaks the recursion.
222 /// Pass identification.
225 /// Provide necessary pointer adjustments for the two base classes.
226 virtual void *getAdjustedAnalysisPointer(const void *ID) {
227 if (ID == &TargetTransformInfo::ID)
228 return (TargetTransformInfo*)this;
232 unsigned getOperationCost(unsigned Opcode, Type *Ty, Type *OpTy) const {
235 // By default, just classify everything as 'basic'.
238 case Instruction::GetElementPtr:
239 llvm_unreachable("Use getGEPCost for GEP operations!");
241 case Instruction::BitCast:
242 assert(OpTy && "Cast instructions must provide the operand type");
243 if (Ty == OpTy || (Ty->isPointerTy() && OpTy->isPointerTy()))
244 // Identity and pointer-to-pointer casts are free.
247 // Otherwise, the default basic cost is used.
250 case Instruction::IntToPtr:
251 // An inttoptr cast is free so long as the input is a legal integer type
252 // which doesn't contain values outside the range of a pointer.
253 if (DL && DL->isLegalInteger(OpTy->getScalarSizeInBits()) &&
254 OpTy->getScalarSizeInBits() <= DL->getPointerSizeInBits())
257 // Otherwise it's not a no-op.
260 case Instruction::PtrToInt:
261 // A ptrtoint cast is free so long as the result is large enough to store
262 // the pointer, and a legal integer type.
263 if (DL && DL->isLegalInteger(OpTy->getScalarSizeInBits()) &&
264 OpTy->getScalarSizeInBits() >= DL->getPointerSizeInBits())
267 // Otherwise it's not a no-op.
270 case Instruction::Trunc:
271 // trunc to a native type is free (assuming the target has compare and
272 // shift-right of the same width).
273 if (DL && DL->isLegalInteger(DL->getTypeSizeInBits(Ty)))
280 unsigned getGEPCost(const Value *Ptr,
281 ArrayRef<const Value *> Operands) const {
282 // In the basic model, we just assume that all-constant GEPs will be folded
283 // into their uses via addressing modes.
284 for (unsigned Idx = 0, Size = Operands.size(); Idx != Size; ++Idx)
285 if (!isa<Constant>(Operands[Idx]))
291 unsigned getCallCost(FunctionType *FTy, int NumArgs = -1) const {
292 assert(FTy && "FunctionType must be provided to this routine.");
294 // The target-independent implementation just measures the size of the
295 // function by approximating that each argument will take on average one
296 // instruction to prepare.
299 // Set the argument number to the number of explicit arguments in the
301 NumArgs = FTy->getNumParams();
303 return TCC_Basic * (NumArgs + 1);
306 unsigned getCallCost(const Function *F, int NumArgs = -1) const {
307 assert(F && "A concrete function must be provided to this routine.");
310 // Set the argument number to the number of explicit arguments in the
312 NumArgs = F->arg_size();
314 if (Intrinsic::ID IID = (Intrinsic::ID)F->getIntrinsicID()) {
315 FunctionType *FTy = F->getFunctionType();
316 SmallVector<Type *, 8> ParamTys(FTy->param_begin(), FTy->param_end());
317 return TopTTI->getIntrinsicCost(IID, FTy->getReturnType(), ParamTys);
320 if (!TopTTI->isLoweredToCall(F))
321 return TCC_Basic; // Give a basic cost if it will be lowered directly.
323 return TopTTI->getCallCost(F->getFunctionType(), NumArgs);
326 unsigned getCallCost(const Function *F,
327 ArrayRef<const Value *> Arguments) const {
328 // Simply delegate to generic handling of the call.
329 // FIXME: We should use instsimplify or something else to catch calls which
330 // will constant fold with these arguments.
331 return TopTTI->getCallCost(F, Arguments.size());
334 unsigned getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
335 ArrayRef<Type *> ParamTys) const {
338 // Intrinsics rarely (if ever) have normal argument setup constraints.
339 // Model them as having a basic instruction cost.
340 // FIXME: This is wrong for libc intrinsics.
343 case Intrinsic::dbg_declare:
344 case Intrinsic::dbg_value:
345 case Intrinsic::invariant_start:
346 case Intrinsic::invariant_end:
347 case Intrinsic::lifetime_start:
348 case Intrinsic::lifetime_end:
349 case Intrinsic::objectsize:
350 case Intrinsic::ptr_annotation:
351 case Intrinsic::var_annotation:
352 // These intrinsics don't actually represent code after lowering.
357 unsigned getIntrinsicCost(Intrinsic::ID IID, Type *RetTy,
358 ArrayRef<const Value *> Arguments) const {
359 // Delegate to the generic intrinsic handling code. This mostly provides an
360 // opportunity for targets to (for example) special case the cost of
361 // certain intrinsics based on constants used as arguments.
362 SmallVector<Type *, 8> ParamTys;
363 ParamTys.reserve(Arguments.size());
364 for (unsigned Idx = 0, Size = Arguments.size(); Idx != Size; ++Idx)
365 ParamTys.push_back(Arguments[Idx]->getType());
366 return TopTTI->getIntrinsicCost(IID, RetTy, ParamTys);
369 unsigned getUserCost(const User *U) const {
371 return TCC_Free; // Model all PHI nodes as free.
373 if (const GEPOperator *GEP = dyn_cast<GEPOperator>(U))
374 // In the basic model we just assume that all-constant GEPs will be
375 // folded into their uses via addressing modes.
376 return GEP->hasAllConstantIndices() ? TCC_Free : TCC_Basic;
378 if (ImmutableCallSite CS = U) {
379 const Function *F = CS.getCalledFunction();
381 // Just use the called value type.
382 Type *FTy = CS.getCalledValue()->getType()->getPointerElementType();
383 return TopTTI->getCallCost(cast<FunctionType>(FTy), CS.arg_size());
386 SmallVector<const Value *, 8> Arguments;
387 for (ImmutableCallSite::arg_iterator AI = CS.arg_begin(),
390 Arguments.push_back(*AI);
392 return TopTTI->getCallCost(F, Arguments);
395 if (const CastInst *CI = dyn_cast<CastInst>(U)) {
396 // Result of a cmp instruction is often extended (to be used by other
397 // cmp instructions, logical or return instructions). These are usually
398 // nop on most sane targets.
399 if (isa<CmpInst>(CI->getOperand(0)))
403 // Otherwise delegate to the fully generic implementations.
404 return getOperationCost(Operator::getOpcode(U), U->getType(),
405 U->getNumOperands() == 1 ?
406 U->getOperand(0)->getType() : 0);
409 bool isLoweredToCall(const Function *F) const {
410 // FIXME: These should almost certainly not be handled here, and instead
411 // handled with the help of TLI or the target itself. This was largely
412 // ported from existing analysis heuristics here so that such refactorings
413 // can take place in the future.
415 if (F->isIntrinsic())
418 if (F->hasLocalLinkage() || !F->hasName())
421 StringRef Name = F->getName();
423 // These will all likely lower to a single selection DAG node.
424 if (Name == "copysign" || Name == "copysignf" || Name == "copysignl" ||
425 Name == "fabs" || Name == "fabsf" || Name == "fabsl" || Name == "sin" ||
426 Name == "sinf" || Name == "sinl" || Name == "cos" || Name == "cosf" ||
427 Name == "cosl" || Name == "sqrt" || Name == "sqrtf" || Name == "sqrtl")
430 // These are all likely to be optimized into something smaller.
431 if (Name == "pow" || Name == "powf" || Name == "powl" || Name == "exp2" ||
432 Name == "exp2l" || Name == "exp2f" || Name == "floor" || Name ==
433 "floorf" || Name == "ceil" || Name == "round" || Name == "ffs" ||
434 Name == "ffsl" || Name == "abs" || Name == "labs" || Name == "llabs")
440 bool isLegalAddImmediate(int64_t Imm) const {
444 bool isLegalICmpImmediate(int64_t Imm) const {
448 bool isLegalAddressingMode(Type *Ty, GlobalValue *BaseGV, int64_t BaseOffset,
449 bool HasBaseReg, int64_t Scale) const {
450 // Guess that reg+reg addressing is allowed. This heuristic is taken from
451 // the implementation of LSR.
452 return !BaseGV && BaseOffset == 0 && Scale <= 1;
455 bool isTruncateFree(Type *Ty1, Type *Ty2) const {
459 bool isTypeLegal(Type *Ty) const {
463 unsigned getJumpBufAlignment() const {
467 unsigned getJumpBufSize() const {
471 bool shouldBuildLookupTables() const {
475 PopcntSupportKind getPopcntSupport(unsigned IntTyWidthInBit) const {
479 unsigned getIntImmCost(const APInt &Imm, Type *Ty) const {
483 unsigned getNumberOfRegisters(bool Vector) const {
487 unsigned getRegisterBitWidth(bool Vector) const {
491 unsigned getMaximumUnrollFactor() const {
495 unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty) const {
499 unsigned getShuffleCost(ShuffleKind Kind, Type *Tp,
500 int Index = 0, Type *SubTp = 0) const {
504 unsigned getCastInstrCost(unsigned Opcode, Type *Dst,
509 unsigned getCFInstrCost(unsigned Opcode) const {
513 unsigned getCmpSelInstrCost(unsigned Opcode, Type *ValTy,
514 Type *CondTy = 0) const {
518 unsigned getVectorInstrCost(unsigned Opcode, Type *Val,
519 unsigned Index = -1) const {
523 unsigned getMemoryOpCost(unsigned Opcode, Type *Src,
525 unsigned AddressSpace) const {
529 unsigned getIntrinsicInstrCost(Intrinsic::ID ID,
531 ArrayRef<Type*> Tys) const {
535 unsigned getNumberOfParts(Type *Tp) const {
540 } // end anonymous namespace
542 INITIALIZE_AG_PASS(NoTTI, TargetTransformInfo, "notti",
543 "No target information", true, true, true)
546 ImmutablePass *llvm::createNoTargetTransformInfoPass() {