1 //===- SimplifyLibCalls.cpp - Optimize specific well-known library calls --===//
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 // This file implements a simple pass that applies a variety of small
11 // optimizations for calls to specific well-known function calls (e.g. runtime
12 // library functions). Any optimization that takes the very simple form
13 // "replace call to library function with simpler code that provides the same
14 // result" belongs in this file.
16 //===----------------------------------------------------------------------===//
18 #define DEBUG_TYPE "simplify-libcalls"
19 #include "llvm/Transforms/Scalar.h"
20 #include "llvm/Transforms/Utils/BuildLibCalls.h"
21 #include "llvm/IRBuilder.h"
22 #include "llvm/Intrinsics.h"
23 #include "llvm/LLVMContext.h"
24 #include "llvm/Module.h"
25 #include "llvm/Pass.h"
26 #include "llvm/ADT/STLExtras.h"
27 #include "llvm/ADT/SmallPtrSet.h"
28 #include "llvm/ADT/Statistic.h"
29 #include "llvm/ADT/StringMap.h"
30 #include "llvm/Analysis/ValueTracking.h"
31 #include "llvm/Support/CommandLine.h"
32 #include "llvm/Support/Debug.h"
33 #include "llvm/Support/raw_ostream.h"
34 #include "llvm/DataLayout.h"
35 #include "llvm/Target/TargetLibraryInfo.h"
36 #include "llvm/Config/config.h" // FIXME: Shouldn't depend on host!
39 STATISTIC(NumSimplified, "Number of library calls simplified");
40 STATISTIC(NumAnnotated, "Number of attributes added to library functions");
42 static cl::opt<bool> UnsafeFPShrink("enable-double-float-shrink", cl::Hidden,
44 cl::desc("Enable unsafe double to float "
45 "shrinking for math lib calls"));
46 //===----------------------------------------------------------------------===//
47 // Optimizer Base Class
48 //===----------------------------------------------------------------------===//
50 /// This class is the abstract base class for the set of optimizations that
51 /// corresponds to one library call.
53 class LibCallOptimization {
57 const TargetLibraryInfo *TLI;
60 LibCallOptimization() { }
61 virtual ~LibCallOptimization() {}
63 /// CallOptimizer - This pure virtual method is implemented by base classes to
64 /// do various optimizations. If this returns null then no transformation was
65 /// performed. If it returns CI, then it transformed the call and CI is to be
66 /// deleted. If it returns something else, replace CI with the new value and
68 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B)
71 Value *OptimizeCall(CallInst *CI, const DataLayout *TD,
72 const TargetLibraryInfo *TLI, IRBuilder<> &B) {
73 Caller = CI->getParent()->getParent();
76 if (CI->getCalledFunction())
77 Context = &CI->getCalledFunction()->getContext();
79 // We never change the calling convention.
80 if (CI->getCallingConv() != llvm::CallingConv::C)
83 return CallOptimizer(CI->getCalledFunction(), CI, B);
86 } // End anonymous namespace.
89 //===----------------------------------------------------------------------===//
91 //===----------------------------------------------------------------------===//
93 /// IsOnlyUsedInZeroEqualityComparison - Return true if it only matters that the
94 /// value is equal or not-equal to zero.
95 static bool IsOnlyUsedInZeroEqualityComparison(Value *V) {
96 for (Value::use_iterator UI = V->use_begin(), E = V->use_end();
98 if (ICmpInst *IC = dyn_cast<ICmpInst>(*UI))
100 if (Constant *C = dyn_cast<Constant>(IC->getOperand(1)))
101 if (C->isNullValue())
103 // Unknown instruction.
109 static bool CallHasFloatingPointArgument(const CallInst *CI) {
110 for (CallInst::const_op_iterator it = CI->op_begin(), e = CI->op_end();
112 if ((*it)->getType()->isFloatingPointTy())
118 /// IsOnlyUsedInEqualityComparison - Return true if it is only used in equality
119 /// comparisons with With.
120 static bool IsOnlyUsedInEqualityComparison(Value *V, Value *With) {
121 for (Value::use_iterator UI = V->use_begin(), E = V->use_end();
123 if (ICmpInst *IC = dyn_cast<ICmpInst>(*UI))
124 if (IC->isEquality() && IC->getOperand(1) == With)
126 // Unknown instruction.
132 //===----------------------------------------------------------------------===//
133 // String and Memory LibCall Optimizations
134 //===----------------------------------------------------------------------===//
137 //===---------------------------------------===//
138 // 'strcpy' Optimizations
140 struct StrCpyOpt : public LibCallOptimization {
141 bool OptChkCall; // True if it's optimizing a __strcpy_chk libcall.
143 StrCpyOpt(bool c) : OptChkCall(c) {}
145 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
146 // Verify the "strcpy" function prototype.
147 unsigned NumParams = OptChkCall ? 3 : 2;
148 FunctionType *FT = Callee->getFunctionType();
149 if (FT->getNumParams() != NumParams ||
150 FT->getReturnType() != FT->getParamType(0) ||
151 FT->getParamType(0) != FT->getParamType(1) ||
152 FT->getParamType(0) != B.getInt8PtrTy())
155 Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
156 if (Dst == Src) // strcpy(x,x) -> x
159 // These optimizations require DataLayout.
162 // See if we can get the length of the input string.
163 uint64_t Len = GetStringLength(Src);
164 if (Len == 0) return 0;
166 // We have enough information to now generate the memcpy call to do the
167 // concatenation for us. Make a memcpy to copy the nul byte with align = 1.
169 !EmitMemCpyChk(Dst, Src,
170 ConstantInt::get(TD->getIntPtrType(*Context), Len),
171 CI->getArgOperand(2), B, TD, TLI))
172 B.CreateMemCpy(Dst, Src,
173 ConstantInt::get(TD->getIntPtrType(*Context), Len), 1);
178 //===---------------------------------------===//
179 // 'stpcpy' Optimizations
181 struct StpCpyOpt: public LibCallOptimization {
182 bool OptChkCall; // True if it's optimizing a __stpcpy_chk libcall.
184 StpCpyOpt(bool c) : OptChkCall(c) {}
186 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
187 // Verify the "stpcpy" function prototype.
188 unsigned NumParams = OptChkCall ? 3 : 2;
189 FunctionType *FT = Callee->getFunctionType();
190 if (FT->getNumParams() != NumParams ||
191 FT->getReturnType() != FT->getParamType(0) ||
192 FT->getParamType(0) != FT->getParamType(1) ||
193 FT->getParamType(0) != B.getInt8PtrTy())
196 // These optimizations require DataLayout.
199 Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
200 if (Dst == Src) { // stpcpy(x,x) -> x+strlen(x)
201 Value *StrLen = EmitStrLen(Src, B, TD, TLI);
202 return StrLen ? B.CreateInBoundsGEP(Dst, StrLen) : 0;
205 // See if we can get the length of the input string.
206 uint64_t Len = GetStringLength(Src);
207 if (Len == 0) return 0;
209 Value *LenV = ConstantInt::get(TD->getIntPtrType(*Context), Len);
210 Value *DstEnd = B.CreateGEP(Dst,
211 ConstantInt::get(TD->getIntPtrType(*Context),
214 // We have enough information to now generate the memcpy call to do the
215 // copy for us. Make a memcpy to copy the nul byte with align = 1.
216 if (!OptChkCall || !EmitMemCpyChk(Dst, Src, LenV, CI->getArgOperand(2), B,
218 B.CreateMemCpy(Dst, Src, LenV, 1);
223 //===---------------------------------------===//
224 // 'strncpy' Optimizations
226 struct StrNCpyOpt : public LibCallOptimization {
227 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
228 FunctionType *FT = Callee->getFunctionType();
229 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
230 FT->getParamType(0) != FT->getParamType(1) ||
231 FT->getParamType(0) != B.getInt8PtrTy() ||
232 !FT->getParamType(2)->isIntegerTy())
235 Value *Dst = CI->getArgOperand(0);
236 Value *Src = CI->getArgOperand(1);
237 Value *LenOp = CI->getArgOperand(2);
239 // See if we can get the length of the input string.
240 uint64_t SrcLen = GetStringLength(Src);
241 if (SrcLen == 0) return 0;
245 // strncpy(x, "", y) -> memset(x, '\0', y, 1)
246 B.CreateMemSet(Dst, B.getInt8('\0'), LenOp, 1);
251 if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(LenOp))
252 Len = LengthArg->getZExtValue();
256 if (Len == 0) return Dst; // strncpy(x, y, 0) -> x
258 // These optimizations require DataLayout.
261 // Let strncpy handle the zero padding
262 if (Len > SrcLen+1) return 0;
264 // strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant]
265 B.CreateMemCpy(Dst, Src,
266 ConstantInt::get(TD->getIntPtrType(*Context), Len), 1);
272 //===---------------------------------------===//
273 // 'strlen' Optimizations
275 struct StrLenOpt : public LibCallOptimization {
276 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
277 FunctionType *FT = Callee->getFunctionType();
278 if (FT->getNumParams() != 1 ||
279 FT->getParamType(0) != B.getInt8PtrTy() ||
280 !FT->getReturnType()->isIntegerTy())
283 Value *Src = CI->getArgOperand(0);
285 // Constant folding: strlen("xyz") -> 3
286 if (uint64_t Len = GetStringLength(Src))
287 return ConstantInt::get(CI->getType(), Len-1);
289 // strlen(x) != 0 --> *x != 0
290 // strlen(x) == 0 --> *x == 0
291 if (IsOnlyUsedInZeroEqualityComparison(CI))
292 return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
298 //===---------------------------------------===//
299 // 'strpbrk' Optimizations
301 struct StrPBrkOpt : public LibCallOptimization {
302 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
303 FunctionType *FT = Callee->getFunctionType();
304 if (FT->getNumParams() != 2 ||
305 FT->getParamType(0) != B.getInt8PtrTy() ||
306 FT->getParamType(1) != FT->getParamType(0) ||
307 FT->getReturnType() != FT->getParamType(0))
311 bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
312 bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
314 // strpbrk(s, "") -> NULL
315 // strpbrk("", s) -> NULL
316 if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
317 return Constant::getNullValue(CI->getType());
320 if (HasS1 && HasS2) {
321 size_t I = S1.find_first_of(S2);
322 if (I == std::string::npos) // No match.
323 return Constant::getNullValue(CI->getType());
325 return B.CreateGEP(CI->getArgOperand(0), B.getInt64(I), "strpbrk");
328 // strpbrk(s, "a") -> strchr(s, 'a')
329 if (TD && HasS2 && S2.size() == 1)
330 return EmitStrChr(CI->getArgOperand(0), S2[0], B, TD, TLI);
336 //===---------------------------------------===//
337 // 'strto*' Optimizations. This handles strtol, strtod, strtof, strtoul, etc.
339 struct StrToOpt : public LibCallOptimization {
340 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
341 FunctionType *FT = Callee->getFunctionType();
342 if ((FT->getNumParams() != 2 && FT->getNumParams() != 3) ||
343 !FT->getParamType(0)->isPointerTy() ||
344 !FT->getParamType(1)->isPointerTy())
347 Value *EndPtr = CI->getArgOperand(1);
348 if (isa<ConstantPointerNull>(EndPtr)) {
349 // With a null EndPtr, this function won't capture the main argument.
350 // It would be readonly too, except that it still may write to errno.
351 CI->addAttribute(1, Attributes::get(Callee->getContext(),
352 Attributes::NoCapture));
359 //===---------------------------------------===//
360 // 'strspn' Optimizations
362 struct StrSpnOpt : public LibCallOptimization {
363 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
364 FunctionType *FT = Callee->getFunctionType();
365 if (FT->getNumParams() != 2 ||
366 FT->getParamType(0) != B.getInt8PtrTy() ||
367 FT->getParamType(1) != FT->getParamType(0) ||
368 !FT->getReturnType()->isIntegerTy())
372 bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
373 bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
375 // strspn(s, "") -> 0
376 // strspn("", s) -> 0
377 if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
378 return Constant::getNullValue(CI->getType());
381 if (HasS1 && HasS2) {
382 size_t Pos = S1.find_first_not_of(S2);
383 if (Pos == StringRef::npos) Pos = S1.size();
384 return ConstantInt::get(CI->getType(), Pos);
391 //===---------------------------------------===//
392 // 'strcspn' Optimizations
394 struct StrCSpnOpt : public LibCallOptimization {
395 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
396 FunctionType *FT = Callee->getFunctionType();
397 if (FT->getNumParams() != 2 ||
398 FT->getParamType(0) != B.getInt8PtrTy() ||
399 FT->getParamType(1) != FT->getParamType(0) ||
400 !FT->getReturnType()->isIntegerTy())
404 bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
405 bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
407 // strcspn("", s) -> 0
408 if (HasS1 && S1.empty())
409 return Constant::getNullValue(CI->getType());
412 if (HasS1 && HasS2) {
413 size_t Pos = S1.find_first_of(S2);
414 if (Pos == StringRef::npos) Pos = S1.size();
415 return ConstantInt::get(CI->getType(), Pos);
418 // strcspn(s, "") -> strlen(s)
419 if (TD && HasS2 && S2.empty())
420 return EmitStrLen(CI->getArgOperand(0), B, TD, TLI);
426 //===---------------------------------------===//
427 // 'strstr' Optimizations
429 struct StrStrOpt : public LibCallOptimization {
430 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
431 FunctionType *FT = Callee->getFunctionType();
432 if (FT->getNumParams() != 2 ||
433 !FT->getParamType(0)->isPointerTy() ||
434 !FT->getParamType(1)->isPointerTy() ||
435 !FT->getReturnType()->isPointerTy())
438 // fold strstr(x, x) -> x.
439 if (CI->getArgOperand(0) == CI->getArgOperand(1))
440 return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
442 // fold strstr(a, b) == a -> strncmp(a, b, strlen(b)) == 0
443 if (TD && IsOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) {
444 Value *StrLen = EmitStrLen(CI->getArgOperand(1), B, TD, TLI);
447 Value *StrNCmp = EmitStrNCmp(CI->getArgOperand(0), CI->getArgOperand(1),
451 for (Value::use_iterator UI = CI->use_begin(), UE = CI->use_end();
453 ICmpInst *Old = cast<ICmpInst>(*UI++);
454 Value *Cmp = B.CreateICmp(Old->getPredicate(), StrNCmp,
455 ConstantInt::getNullValue(StrNCmp->getType()),
457 Old->replaceAllUsesWith(Cmp);
458 Old->eraseFromParent();
463 // See if either input string is a constant string.
464 StringRef SearchStr, ToFindStr;
465 bool HasStr1 = getConstantStringInfo(CI->getArgOperand(0), SearchStr);
466 bool HasStr2 = getConstantStringInfo(CI->getArgOperand(1), ToFindStr);
468 // fold strstr(x, "") -> x.
469 if (HasStr2 && ToFindStr.empty())
470 return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
472 // If both strings are known, constant fold it.
473 if (HasStr1 && HasStr2) {
474 std::string::size_type Offset = SearchStr.find(ToFindStr);
476 if (Offset == StringRef::npos) // strstr("foo", "bar") -> null
477 return Constant::getNullValue(CI->getType());
479 // strstr("abcd", "bc") -> gep((char*)"abcd", 1)
480 Value *Result = CastToCStr(CI->getArgOperand(0), B);
481 Result = B.CreateConstInBoundsGEP1_64(Result, Offset, "strstr");
482 return B.CreateBitCast(Result, CI->getType());
485 // fold strstr(x, "y") -> strchr(x, 'y').
486 if (HasStr2 && ToFindStr.size() == 1) {
487 Value *StrChr= EmitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TD, TLI);
488 return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : 0;
495 //===---------------------------------------===//
496 // 'memcmp' Optimizations
498 struct MemCmpOpt : public LibCallOptimization {
499 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
500 FunctionType *FT = Callee->getFunctionType();
501 if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
502 !FT->getParamType(1)->isPointerTy() ||
503 !FT->getReturnType()->isIntegerTy(32))
506 Value *LHS = CI->getArgOperand(0), *RHS = CI->getArgOperand(1);
508 if (LHS == RHS) // memcmp(s,s,x) -> 0
509 return Constant::getNullValue(CI->getType());
511 // Make sure we have a constant length.
512 ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
514 uint64_t Len = LenC->getZExtValue();
516 if (Len == 0) // memcmp(s1,s2,0) -> 0
517 return Constant::getNullValue(CI->getType());
519 // memcmp(S1,S2,1) -> *(unsigned char*)LHS - *(unsigned char*)RHS
521 Value *LHSV = B.CreateZExt(B.CreateLoad(CastToCStr(LHS, B), "lhsc"),
522 CI->getType(), "lhsv");
523 Value *RHSV = B.CreateZExt(B.CreateLoad(CastToCStr(RHS, B), "rhsc"),
524 CI->getType(), "rhsv");
525 return B.CreateSub(LHSV, RHSV, "chardiff");
528 // Constant folding: memcmp(x, y, l) -> cnst (all arguments are constant)
529 StringRef LHSStr, RHSStr;
530 if (getConstantStringInfo(LHS, LHSStr) &&
531 getConstantStringInfo(RHS, RHSStr)) {
532 // Make sure we're not reading out-of-bounds memory.
533 if (Len > LHSStr.size() || Len > RHSStr.size())
535 uint64_t Ret = memcmp(LHSStr.data(), RHSStr.data(), Len);
536 return ConstantInt::get(CI->getType(), Ret);
543 //===---------------------------------------===//
544 // 'memcpy' Optimizations
546 struct MemCpyOpt : public LibCallOptimization {
547 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
548 // These optimizations require DataLayout.
551 FunctionType *FT = Callee->getFunctionType();
552 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
553 !FT->getParamType(0)->isPointerTy() ||
554 !FT->getParamType(1)->isPointerTy() ||
555 FT->getParamType(2) != TD->getIntPtrType(*Context))
558 // memcpy(x, y, n) -> llvm.memcpy(x, y, n, 1)
559 B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
560 CI->getArgOperand(2), 1);
561 return CI->getArgOperand(0);
565 //===---------------------------------------===//
566 // 'memmove' Optimizations
568 struct MemMoveOpt : public LibCallOptimization {
569 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
570 // These optimizations require DataLayout.
573 FunctionType *FT = Callee->getFunctionType();
574 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
575 !FT->getParamType(0)->isPointerTy() ||
576 !FT->getParamType(1)->isPointerTy() ||
577 FT->getParamType(2) != TD->getIntPtrType(*Context))
580 // memmove(x, y, n) -> llvm.memmove(x, y, n, 1)
581 B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
582 CI->getArgOperand(2), 1);
583 return CI->getArgOperand(0);
587 //===---------------------------------------===//
588 // 'memset' Optimizations
590 struct MemSetOpt : public LibCallOptimization {
591 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
592 // These optimizations require DataLayout.
595 FunctionType *FT = Callee->getFunctionType();
596 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
597 !FT->getParamType(0)->isPointerTy() ||
598 !FT->getParamType(1)->isIntegerTy() ||
599 FT->getParamType(2) != TD->getIntPtrType(*Context))
602 // memset(p, v, n) -> llvm.memset(p, v, n, 1)
603 Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
604 B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
605 return CI->getArgOperand(0);
609 //===----------------------------------------------------------------------===//
610 // Math Library Optimizations
611 //===----------------------------------------------------------------------===//
613 //===---------------------------------------===//
614 // Double -> Float Shrinking Optimizations for Unary Functions like 'floor'
616 struct UnaryDoubleFPOpt : public LibCallOptimization {
618 UnaryDoubleFPOpt(bool CheckReturnType): CheckRetType(CheckReturnType) {}
619 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
620 FunctionType *FT = Callee->getFunctionType();
621 if (FT->getNumParams() != 1 || !FT->getReturnType()->isDoubleTy() ||
622 !FT->getParamType(0)->isDoubleTy())
626 // Check if all the uses for function like 'sin' are converted to float.
627 for (Value::use_iterator UseI = CI->use_begin(); UseI != CI->use_end();
629 FPTruncInst *Cast = dyn_cast<FPTruncInst>(*UseI);
630 if (Cast == 0 || !Cast->getType()->isFloatTy())
635 // If this is something like 'floor((double)floatval)', convert to floorf.
636 FPExtInst *Cast = dyn_cast<FPExtInst>(CI->getArgOperand(0));
637 if (Cast == 0 || !Cast->getOperand(0)->getType()->isFloatTy())
640 // floor((double)floatval) -> (double)floorf(floatval)
641 Value *V = Cast->getOperand(0);
642 V = EmitUnaryFloatFnCall(V, Callee->getName(), B, Callee->getAttributes());
643 return B.CreateFPExt(V, B.getDoubleTy());
647 //===---------------------------------------===//
648 // 'cos*' Optimizations
649 struct CosOpt : public LibCallOptimization {
650 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
652 if (UnsafeFPShrink && Callee->getName() == "cos" &&
653 TLI->has(LibFunc::cosf)) {
654 UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
655 Ret = UnsafeUnaryDoubleFP.CallOptimizer(Callee, CI, B);
658 FunctionType *FT = Callee->getFunctionType();
659 // Just make sure this has 1 argument of FP type, which matches the
661 if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
662 !FT->getParamType(0)->isFloatingPointTy())
666 Value *Op1 = CI->getArgOperand(0);
667 if (BinaryOperator::isFNeg(Op1)) {
668 BinaryOperator *BinExpr = cast<BinaryOperator>(Op1);
669 return B.CreateCall(Callee, BinExpr->getOperand(1), "cos");
675 //===---------------------------------------===//
676 // 'pow*' Optimizations
678 struct PowOpt : public LibCallOptimization {
679 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
681 if (UnsafeFPShrink && Callee->getName() == "pow" &&
682 TLI->has(LibFunc::powf)) {
683 UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
684 Ret = UnsafeUnaryDoubleFP.CallOptimizer(Callee, CI, B);
687 FunctionType *FT = Callee->getFunctionType();
688 // Just make sure this has 2 arguments of the same FP type, which match the
690 if (FT->getNumParams() != 2 || FT->getReturnType() != FT->getParamType(0) ||
691 FT->getParamType(0) != FT->getParamType(1) ||
692 !FT->getParamType(0)->isFloatingPointTy())
695 Value *Op1 = CI->getArgOperand(0), *Op2 = CI->getArgOperand(1);
696 if (ConstantFP *Op1C = dyn_cast<ConstantFP>(Op1)) {
697 if (Op1C->isExactlyValue(1.0)) // pow(1.0, x) -> 1.0
699 if (Op1C->isExactlyValue(2.0)) // pow(2.0, x) -> exp2(x)
700 return EmitUnaryFloatFnCall(Op2, "exp2", B, Callee->getAttributes());
703 ConstantFP *Op2C = dyn_cast<ConstantFP>(Op2);
704 if (Op2C == 0) return Ret;
706 if (Op2C->getValueAPF().isZero()) // pow(x, 0.0) -> 1.0
707 return ConstantFP::get(CI->getType(), 1.0);
709 if (Op2C->isExactlyValue(0.5)) {
710 // Expand pow(x, 0.5) to (x == -infinity ? +infinity : fabs(sqrt(x))).
711 // This is faster than calling pow, and still handles negative zero
712 // and negative infinity correctly.
713 // TODO: In fast-math mode, this could be just sqrt(x).
714 // TODO: In finite-only mode, this could be just fabs(sqrt(x)).
715 Value *Inf = ConstantFP::getInfinity(CI->getType());
716 Value *NegInf = ConstantFP::getInfinity(CI->getType(), true);
717 Value *Sqrt = EmitUnaryFloatFnCall(Op1, "sqrt", B,
718 Callee->getAttributes());
719 Value *FAbs = EmitUnaryFloatFnCall(Sqrt, "fabs", B,
720 Callee->getAttributes());
721 Value *FCmp = B.CreateFCmpOEQ(Op1, NegInf);
722 Value *Sel = B.CreateSelect(FCmp, Inf, FAbs);
726 if (Op2C->isExactlyValue(1.0)) // pow(x, 1.0) -> x
728 if (Op2C->isExactlyValue(2.0)) // pow(x, 2.0) -> x*x
729 return B.CreateFMul(Op1, Op1, "pow2");
730 if (Op2C->isExactlyValue(-1.0)) // pow(x, -1.0) -> 1.0/x
731 return B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0),
737 //===---------------------------------------===//
738 // 'exp2' Optimizations
740 struct Exp2Opt : public LibCallOptimization {
741 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
743 if (UnsafeFPShrink && Callee->getName() == "exp2" &&
744 TLI->has(LibFunc::exp2)) {
745 UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
746 Ret = UnsafeUnaryDoubleFP.CallOptimizer(Callee, CI, B);
749 FunctionType *FT = Callee->getFunctionType();
750 // Just make sure this has 1 argument of FP type, which matches the
752 if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
753 !FT->getParamType(0)->isFloatingPointTy())
756 Value *Op = CI->getArgOperand(0);
757 // Turn exp2(sitofp(x)) -> ldexp(1.0, sext(x)) if sizeof(x) <= 32
758 // Turn exp2(uitofp(x)) -> ldexp(1.0, zext(x)) if sizeof(x) < 32
760 if (SIToFPInst *OpC = dyn_cast<SIToFPInst>(Op)) {
761 if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() <= 32)
762 LdExpArg = B.CreateSExt(OpC->getOperand(0), B.getInt32Ty());
763 } else if (UIToFPInst *OpC = dyn_cast<UIToFPInst>(Op)) {
764 if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() < 32)
765 LdExpArg = B.CreateZExt(OpC->getOperand(0), B.getInt32Ty());
770 if (Op->getType()->isFloatTy())
772 else if (Op->getType()->isDoubleTy())
777 Constant *One = ConstantFP::get(*Context, APFloat(1.0f));
778 if (!Op->getType()->isFloatTy())
779 One = ConstantExpr::getFPExtend(One, Op->getType());
781 Module *M = Caller->getParent();
782 Value *Callee = M->getOrInsertFunction(Name, Op->getType(),
784 B.getInt32Ty(), NULL);
785 CallInst *CI = B.CreateCall2(Callee, One, LdExpArg);
786 if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts()))
787 CI->setCallingConv(F->getCallingConv());
795 //===----------------------------------------------------------------------===//
796 // Integer Optimizations
797 //===----------------------------------------------------------------------===//
799 //===---------------------------------------===//
800 // 'ffs*' Optimizations
802 struct FFSOpt : public LibCallOptimization {
803 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
804 FunctionType *FT = Callee->getFunctionType();
805 // Just make sure this has 2 arguments of the same FP type, which match the
807 if (FT->getNumParams() != 1 ||
808 !FT->getReturnType()->isIntegerTy(32) ||
809 !FT->getParamType(0)->isIntegerTy())
812 Value *Op = CI->getArgOperand(0);
815 if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
816 if (CI->getValue() == 0) // ffs(0) -> 0.
817 return Constant::getNullValue(CI->getType());
818 // ffs(c) -> cttz(c)+1
819 return B.getInt32(CI->getValue().countTrailingZeros() + 1);
822 // ffs(x) -> x != 0 ? (i32)llvm.cttz(x)+1 : 0
823 Type *ArgType = Op->getType();
824 Value *F = Intrinsic::getDeclaration(Callee->getParent(),
825 Intrinsic::cttz, ArgType);
826 Value *V = B.CreateCall2(F, Op, B.getFalse(), "cttz");
827 V = B.CreateAdd(V, ConstantInt::get(V->getType(), 1));
828 V = B.CreateIntCast(V, B.getInt32Ty(), false);
830 Value *Cond = B.CreateICmpNE(Op, Constant::getNullValue(ArgType));
831 return B.CreateSelect(Cond, V, B.getInt32(0));
835 //===---------------------------------------===//
836 // 'isdigit' Optimizations
838 struct IsDigitOpt : public LibCallOptimization {
839 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
840 FunctionType *FT = Callee->getFunctionType();
841 // We require integer(i32)
842 if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
843 !FT->getParamType(0)->isIntegerTy(32))
846 // isdigit(c) -> (c-'0') <u 10
847 Value *Op = CI->getArgOperand(0);
848 Op = B.CreateSub(Op, B.getInt32('0'), "isdigittmp");
849 Op = B.CreateICmpULT(Op, B.getInt32(10), "isdigit");
850 return B.CreateZExt(Op, CI->getType());
854 //===---------------------------------------===//
855 // 'isascii' Optimizations
857 struct IsAsciiOpt : public LibCallOptimization {
858 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
859 FunctionType *FT = Callee->getFunctionType();
860 // We require integer(i32)
861 if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
862 !FT->getParamType(0)->isIntegerTy(32))
865 // isascii(c) -> c <u 128
866 Value *Op = CI->getArgOperand(0);
867 Op = B.CreateICmpULT(Op, B.getInt32(128), "isascii");
868 return B.CreateZExt(Op, CI->getType());
872 //===---------------------------------------===//
873 // 'abs', 'labs', 'llabs' Optimizations
875 struct AbsOpt : public LibCallOptimization {
876 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
877 FunctionType *FT = Callee->getFunctionType();
878 // We require integer(integer) where the types agree.
879 if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
880 FT->getParamType(0) != FT->getReturnType())
883 // abs(x) -> x >s -1 ? x : -x
884 Value *Op = CI->getArgOperand(0);
885 Value *Pos = B.CreateICmpSGT(Op, Constant::getAllOnesValue(Op->getType()),
887 Value *Neg = B.CreateNeg(Op, "neg");
888 return B.CreateSelect(Pos, Op, Neg);
893 //===---------------------------------------===//
894 // 'toascii' Optimizations
896 struct ToAsciiOpt : public LibCallOptimization {
897 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
898 FunctionType *FT = Callee->getFunctionType();
899 // We require i32(i32)
900 if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
901 !FT->getParamType(0)->isIntegerTy(32))
904 // isascii(c) -> c & 0x7f
905 return B.CreateAnd(CI->getArgOperand(0),
906 ConstantInt::get(CI->getType(),0x7F));
910 //===----------------------------------------------------------------------===//
911 // Formatting and IO Optimizations
912 //===----------------------------------------------------------------------===//
914 //===---------------------------------------===//
915 // 'printf' Optimizations
917 struct PrintFOpt : public LibCallOptimization {
918 Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
920 // Check for a fixed format string.
922 if (!getConstantStringInfo(CI->getArgOperand(0), FormatStr))
925 // Empty format string -> noop.
926 if (FormatStr.empty()) // Tolerate printf's declared void.
927 return CI->use_empty() ? (Value*)CI :
928 ConstantInt::get(CI->getType(), 0);
930 // Do not do any of the following transformations if the printf return value
931 // is used, in general the printf return value is not compatible with either
932 // putchar() or puts().
933 if (!CI->use_empty())
936 // printf("x") -> putchar('x'), even for '%'.
937 if (FormatStr.size() == 1) {
938 Value *Res = EmitPutChar(B.getInt32(FormatStr[0]), B, TD, TLI);
939 if (CI->use_empty() || !Res) return Res;
940 return B.CreateIntCast(Res, CI->getType(), true);
943 // printf("foo\n") --> puts("foo")
944 if (FormatStr[FormatStr.size()-1] == '\n' &&
945 FormatStr.find('%') == std::string::npos) { // no format characters.
946 // Create a string literal with no \n on it. We expect the constant merge
947 // pass to be run after this pass, to merge duplicate strings.
948 FormatStr = FormatStr.drop_back();
949 Value *GV = B.CreateGlobalString(FormatStr, "str");
950 Value *NewCI = EmitPutS(GV, B, TD, TLI);
951 return (CI->use_empty() || !NewCI) ?
953 ConstantInt::get(CI->getType(), FormatStr.size()+1);
956 // Optimize specific format strings.
957 // printf("%c", chr) --> putchar(chr)
958 if (FormatStr == "%c" && CI->getNumArgOperands() > 1 &&
959 CI->getArgOperand(1)->getType()->isIntegerTy()) {
960 Value *Res = EmitPutChar(CI->getArgOperand(1), B, TD, TLI);
962 if (CI->use_empty() || !Res) return Res;
963 return B.CreateIntCast(Res, CI->getType(), true);
966 // printf("%s\n", str) --> puts(str)
967 if (FormatStr == "%s\n" && CI->getNumArgOperands() > 1 &&
968 CI->getArgOperand(1)->getType()->isPointerTy()) {
969 return EmitPutS(CI->getArgOperand(1), B, TD, TLI);
974 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
975 // Require one fixed pointer argument and an integer/void result.
976 FunctionType *FT = Callee->getFunctionType();
977 if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
978 !(FT->getReturnType()->isIntegerTy() ||
979 FT->getReturnType()->isVoidTy()))
982 if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
986 // printf(format, ...) -> iprintf(format, ...) if no floating point
988 if (TLI->has(LibFunc::iprintf) && !CallHasFloatingPointArgument(CI)) {
989 Module *M = B.GetInsertBlock()->getParent()->getParent();
990 Constant *IPrintFFn =
991 M->getOrInsertFunction("iprintf", FT, Callee->getAttributes());
992 CallInst *New = cast<CallInst>(CI->clone());
993 New->setCalledFunction(IPrintFFn);
1001 //===---------------------------------------===//
1002 // 'sprintf' Optimizations
1004 struct SPrintFOpt : public LibCallOptimization {
1005 Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
1007 // Check for a fixed format string.
1008 StringRef FormatStr;
1009 if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
1012 // If we just have a format string (nothing else crazy) transform it.
1013 if (CI->getNumArgOperands() == 2) {
1014 // Make sure there's no % in the constant array. We could try to handle
1015 // %% -> % in the future if we cared.
1016 for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
1017 if (FormatStr[i] == '%')
1018 return 0; // we found a format specifier, bail out.
1020 // These optimizations require DataLayout.
1023 // sprintf(str, fmt) -> llvm.memcpy(str, fmt, strlen(fmt)+1, 1)
1024 B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
1025 ConstantInt::get(TD->getIntPtrType(*Context), // Copy the
1026 FormatStr.size() + 1), 1); // nul byte.
1027 return ConstantInt::get(CI->getType(), FormatStr.size());
1030 // The remaining optimizations require the format string to be "%s" or "%c"
1031 // and have an extra operand.
1032 if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
1033 CI->getNumArgOperands() < 3)
1036 // Decode the second character of the format string.
1037 if (FormatStr[1] == 'c') {
1038 // sprintf(dst, "%c", chr) --> *(i8*)dst = chr; *((i8*)dst+1) = 0
1039 if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
1040 Value *V = B.CreateTrunc(CI->getArgOperand(2), B.getInt8Ty(), "char");
1041 Value *Ptr = CastToCStr(CI->getArgOperand(0), B);
1042 B.CreateStore(V, Ptr);
1043 Ptr = B.CreateGEP(Ptr, B.getInt32(1), "nul");
1044 B.CreateStore(B.getInt8(0), Ptr);
1046 return ConstantInt::get(CI->getType(), 1);
1049 if (FormatStr[1] == 's') {
1050 // These optimizations require DataLayout.
1053 // sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1)
1054 if (!CI->getArgOperand(2)->getType()->isPointerTy()) return 0;
1056 Value *Len = EmitStrLen(CI->getArgOperand(2), B, TD, TLI);
1059 Value *IncLen = B.CreateAdd(Len,
1060 ConstantInt::get(Len->getType(), 1),
1062 B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(2), IncLen, 1);
1064 // The sprintf result is the unincremented number of bytes in the string.
1065 return B.CreateIntCast(Len, CI->getType(), false);
1070 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1071 // Require two fixed pointer arguments and an integer result.
1072 FunctionType *FT = Callee->getFunctionType();
1073 if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
1074 !FT->getParamType(1)->isPointerTy() ||
1075 !FT->getReturnType()->isIntegerTy())
1078 if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
1082 // sprintf(str, format, ...) -> siprintf(str, format, ...) if no floating
1084 if (TLI->has(LibFunc::siprintf) && !CallHasFloatingPointArgument(CI)) {
1085 Module *M = B.GetInsertBlock()->getParent()->getParent();
1086 Constant *SIPrintFFn =
1087 M->getOrInsertFunction("siprintf", FT, Callee->getAttributes());
1088 CallInst *New = cast<CallInst>(CI->clone());
1089 New->setCalledFunction(SIPrintFFn);
1097 //===---------------------------------------===//
1098 // 'fwrite' Optimizations
1100 struct FWriteOpt : public LibCallOptimization {
1101 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1102 // Require a pointer, an integer, an integer, a pointer, returning integer.
1103 FunctionType *FT = Callee->getFunctionType();
1104 if (FT->getNumParams() != 4 || !FT->getParamType(0)->isPointerTy() ||
1105 !FT->getParamType(1)->isIntegerTy() ||
1106 !FT->getParamType(2)->isIntegerTy() ||
1107 !FT->getParamType(3)->isPointerTy() ||
1108 !FT->getReturnType()->isIntegerTy())
1111 // Get the element size and count.
1112 ConstantInt *SizeC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
1113 ConstantInt *CountC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
1114 if (!SizeC || !CountC) return 0;
1115 uint64_t Bytes = SizeC->getZExtValue()*CountC->getZExtValue();
1117 // If this is writing zero records, remove the call (it's a noop).
1119 return ConstantInt::get(CI->getType(), 0);
1121 // If this is writing one byte, turn it into fputc.
1122 // This optimisation is only valid, if the return value is unused.
1123 if (Bytes == 1 && CI->use_empty()) { // fwrite(S,1,1,F) -> fputc(S[0],F)
1124 Value *Char = B.CreateLoad(CastToCStr(CI->getArgOperand(0), B), "char");
1125 Value *NewCI = EmitFPutC(Char, CI->getArgOperand(3), B, TD, TLI);
1126 return NewCI ? ConstantInt::get(CI->getType(), 1) : 0;
1133 //===---------------------------------------===//
1134 // 'fputs' Optimizations
1136 struct FPutsOpt : public LibCallOptimization {
1137 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1138 // These optimizations require DataLayout.
1141 // Require two pointers. Also, we can't optimize if return value is used.
1142 FunctionType *FT = Callee->getFunctionType();
1143 if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
1144 !FT->getParamType(1)->isPointerTy() ||
1148 // fputs(s,F) --> fwrite(s,1,strlen(s),F)
1149 uint64_t Len = GetStringLength(CI->getArgOperand(0));
1151 // Known to have no uses (see above).
1152 return EmitFWrite(CI->getArgOperand(0),
1153 ConstantInt::get(TD->getIntPtrType(*Context), Len-1),
1154 CI->getArgOperand(1), B, TD, TLI);
1158 //===---------------------------------------===//
1159 // 'fprintf' Optimizations
1161 struct FPrintFOpt : public LibCallOptimization {
1162 Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
1164 // All the optimizations depend on the format string.
1165 StringRef FormatStr;
1166 if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
1169 // fprintf(F, "foo") --> fwrite("foo", 3, 1, F)
1170 if (CI->getNumArgOperands() == 2) {
1171 for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
1172 if (FormatStr[i] == '%') // Could handle %% -> % if we cared.
1173 return 0; // We found a format specifier.
1175 // These optimizations require DataLayout.
1178 Value *NewCI = EmitFWrite(CI->getArgOperand(1),
1179 ConstantInt::get(TD->getIntPtrType(*Context),
1181 CI->getArgOperand(0), B, TD, TLI);
1182 return NewCI ? ConstantInt::get(CI->getType(), FormatStr.size()) : 0;
1185 // The remaining optimizations require the format string to be "%s" or "%c"
1186 // and have an extra operand.
1187 if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
1188 CI->getNumArgOperands() < 3)
1191 // Decode the second character of the format string.
1192 if (FormatStr[1] == 'c') {
1193 // fprintf(F, "%c", chr) --> fputc(chr, F)
1194 if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
1195 Value *NewCI = EmitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B,
1197 return NewCI ? ConstantInt::get(CI->getType(), 1) : 0;
1200 if (FormatStr[1] == 's') {
1201 // fprintf(F, "%s", str) --> fputs(str, F)
1202 if (!CI->getArgOperand(2)->getType()->isPointerTy() || !CI->use_empty())
1204 return EmitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TD, TLI);
1209 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1210 // Require two fixed paramters as pointers and integer result.
1211 FunctionType *FT = Callee->getFunctionType();
1212 if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
1213 !FT->getParamType(1)->isPointerTy() ||
1214 !FT->getReturnType()->isIntegerTy())
1217 if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
1221 // fprintf(stream, format, ...) -> fiprintf(stream, format, ...) if no
1222 // floating point arguments.
1223 if (TLI->has(LibFunc::fiprintf) && !CallHasFloatingPointArgument(CI)) {
1224 Module *M = B.GetInsertBlock()->getParent()->getParent();
1225 Constant *FIPrintFFn =
1226 M->getOrInsertFunction("fiprintf", FT, Callee->getAttributes());
1227 CallInst *New = cast<CallInst>(CI->clone());
1228 New->setCalledFunction(FIPrintFFn);
1236 //===---------------------------------------===//
1237 // 'puts' Optimizations
1239 struct PutsOpt : public LibCallOptimization {
1240 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1241 // Require one fixed pointer argument and an integer/void result.
1242 FunctionType *FT = Callee->getFunctionType();
1243 if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
1244 !(FT->getReturnType()->isIntegerTy() ||
1245 FT->getReturnType()->isVoidTy()))
1248 // Check for a constant string.
1250 if (!getConstantStringInfo(CI->getArgOperand(0), Str))
1253 if (Str.empty() && CI->use_empty()) {
1254 // puts("") -> putchar('\n')
1255 Value *Res = EmitPutChar(B.getInt32('\n'), B, TD, TLI);
1256 if (CI->use_empty() || !Res) return Res;
1257 return B.CreateIntCast(Res, CI->getType(), true);
1264 } // end anonymous namespace.
1266 //===----------------------------------------------------------------------===//
1267 // SimplifyLibCalls Pass Implementation
1268 //===----------------------------------------------------------------------===//
1271 /// This pass optimizes well known library functions from libc and libm.
1273 class SimplifyLibCalls : public FunctionPass {
1274 TargetLibraryInfo *TLI;
1276 StringMap<LibCallOptimization*> Optimizations;
1277 // String and Memory LibCall Optimizations
1278 StrCpyOpt StrCpy; StrCpyOpt StrCpyChk;
1279 StpCpyOpt StpCpy; StpCpyOpt StpCpyChk;
1281 StrLenOpt StrLen; StrPBrkOpt StrPBrk;
1282 StrToOpt StrTo; StrSpnOpt StrSpn; StrCSpnOpt StrCSpn; StrStrOpt StrStr;
1283 MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
1284 // Math Library Optimizations
1285 CosOpt Cos; PowOpt Pow; Exp2Opt Exp2;
1286 UnaryDoubleFPOpt UnaryDoubleFP, UnsafeUnaryDoubleFP;
1287 // Integer Optimizations
1288 FFSOpt FFS; AbsOpt Abs; IsDigitOpt IsDigit; IsAsciiOpt IsAscii;
1290 // Formatting and IO Optimizations
1291 SPrintFOpt SPrintF; PrintFOpt PrintF;
1292 FWriteOpt FWrite; FPutsOpt FPuts; FPrintFOpt FPrintF;
1295 bool Modified; // This is only used by doInitialization.
1297 static char ID; // Pass identification
1298 SimplifyLibCalls() : FunctionPass(ID), StrCpy(false), StrCpyChk(true),
1299 StpCpy(false), StpCpyChk(true),
1300 UnaryDoubleFP(false), UnsafeUnaryDoubleFP(true) {
1301 initializeSimplifyLibCallsPass(*PassRegistry::getPassRegistry());
1303 void AddOpt(LibFunc::Func F, LibCallOptimization* Opt);
1304 void AddOpt(LibFunc::Func F1, LibFunc::Func F2, LibCallOptimization* Opt);
1306 void InitOptimizations();
1307 bool runOnFunction(Function &F);
1309 void setDoesNotAccessMemory(Function &F);
1310 void setOnlyReadsMemory(Function &F);
1311 void setDoesNotThrow(Function &F);
1312 void setDoesNotCapture(Function &F, unsigned n);
1313 void setDoesNotAlias(Function &F, unsigned n);
1314 bool doInitialization(Module &M);
1316 void inferPrototypeAttributes(Function &F);
1317 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
1318 AU.addRequired<TargetLibraryInfo>();
1321 } // end anonymous namespace.
1323 char SimplifyLibCalls::ID = 0;
1325 INITIALIZE_PASS_BEGIN(SimplifyLibCalls, "simplify-libcalls",
1326 "Simplify well-known library calls", false, false)
1327 INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfo)
1328 INITIALIZE_PASS_END(SimplifyLibCalls, "simplify-libcalls",
1329 "Simplify well-known library calls", false, false)
1331 // Public interface to the Simplify LibCalls pass.
1332 FunctionPass *llvm::createSimplifyLibCallsPass() {
1333 return new SimplifyLibCalls();
1336 void SimplifyLibCalls::AddOpt(LibFunc::Func F, LibCallOptimization* Opt) {
1338 Optimizations[TLI->getName(F)] = Opt;
1341 void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2,
1342 LibCallOptimization* Opt) {
1343 if (TLI->has(F1) && TLI->has(F2))
1344 Optimizations[TLI->getName(F1)] = Opt;
1347 /// Optimizations - Populate the Optimizations map with all the optimizations
1349 void SimplifyLibCalls::InitOptimizations() {
1350 // String and Memory LibCall Optimizations
1351 Optimizations["strcpy"] = &StrCpy;
1352 Optimizations["strncpy"] = &StrNCpy;
1353 Optimizations["stpcpy"] = &StpCpy;
1354 Optimizations["strlen"] = &StrLen;
1355 Optimizations["strpbrk"] = &StrPBrk;
1356 Optimizations["strtol"] = &StrTo;
1357 Optimizations["strtod"] = &StrTo;
1358 Optimizations["strtof"] = &StrTo;
1359 Optimizations["strtoul"] = &StrTo;
1360 Optimizations["strtoll"] = &StrTo;
1361 Optimizations["strtold"] = &StrTo;
1362 Optimizations["strtoull"] = &StrTo;
1363 Optimizations["strspn"] = &StrSpn;
1364 Optimizations["strcspn"] = &StrCSpn;
1365 Optimizations["strstr"] = &StrStr;
1366 Optimizations["memcmp"] = &MemCmp;
1367 AddOpt(LibFunc::memcpy, &MemCpy);
1368 Optimizations["memmove"] = &MemMove;
1369 AddOpt(LibFunc::memset, &MemSet);
1371 // _chk variants of String and Memory LibCall Optimizations.
1372 Optimizations["__strcpy_chk"] = &StrCpyChk;
1373 Optimizations["__stpcpy_chk"] = &StpCpyChk;
1375 // Math Library Optimizations
1376 Optimizations["cosf"] = &Cos;
1377 Optimizations["cos"] = &Cos;
1378 Optimizations["cosl"] = &Cos;
1379 Optimizations["powf"] = &Pow;
1380 Optimizations["pow"] = &Pow;
1381 Optimizations["powl"] = &Pow;
1382 Optimizations["llvm.pow.f32"] = &Pow;
1383 Optimizations["llvm.pow.f64"] = &Pow;
1384 Optimizations["llvm.pow.f80"] = &Pow;
1385 Optimizations["llvm.pow.f128"] = &Pow;
1386 Optimizations["llvm.pow.ppcf128"] = &Pow;
1387 Optimizations["exp2l"] = &Exp2;
1388 Optimizations["exp2"] = &Exp2;
1389 Optimizations["exp2f"] = &Exp2;
1390 Optimizations["llvm.exp2.ppcf128"] = &Exp2;
1391 Optimizations["llvm.exp2.f128"] = &Exp2;
1392 Optimizations["llvm.exp2.f80"] = &Exp2;
1393 Optimizations["llvm.exp2.f64"] = &Exp2;
1394 Optimizations["llvm.exp2.f32"] = &Exp2;
1396 AddOpt(LibFunc::ceil, LibFunc::ceilf, &UnaryDoubleFP);
1397 AddOpt(LibFunc::fabs, LibFunc::fabsf, &UnaryDoubleFP);
1398 AddOpt(LibFunc::floor, LibFunc::floorf, &UnaryDoubleFP);
1399 AddOpt(LibFunc::rint, LibFunc::rintf, &UnaryDoubleFP);
1400 AddOpt(LibFunc::round, LibFunc::roundf, &UnaryDoubleFP);
1401 AddOpt(LibFunc::nearbyint, LibFunc::nearbyintf, &UnaryDoubleFP);
1402 AddOpt(LibFunc::trunc, LibFunc::truncf, &UnaryDoubleFP);
1404 if(UnsafeFPShrink) {
1405 AddOpt(LibFunc::acos, LibFunc::acosf, &UnsafeUnaryDoubleFP);
1406 AddOpt(LibFunc::acosh, LibFunc::acoshf, &UnsafeUnaryDoubleFP);
1407 AddOpt(LibFunc::asin, LibFunc::asinf, &UnsafeUnaryDoubleFP);
1408 AddOpt(LibFunc::asinh, LibFunc::asinhf, &UnsafeUnaryDoubleFP);
1409 AddOpt(LibFunc::atan, LibFunc::atanf, &UnsafeUnaryDoubleFP);
1410 AddOpt(LibFunc::atanh, LibFunc::atanhf, &UnsafeUnaryDoubleFP);
1411 AddOpt(LibFunc::cbrt, LibFunc::cbrtf, &UnsafeUnaryDoubleFP);
1412 AddOpt(LibFunc::cosh, LibFunc::coshf, &UnsafeUnaryDoubleFP);
1413 AddOpt(LibFunc::exp, LibFunc::expf, &UnsafeUnaryDoubleFP);
1414 AddOpt(LibFunc::exp10, LibFunc::exp10f, &UnsafeUnaryDoubleFP);
1415 AddOpt(LibFunc::expm1, LibFunc::expm1f, &UnsafeUnaryDoubleFP);
1416 AddOpt(LibFunc::log, LibFunc::logf, &UnsafeUnaryDoubleFP);
1417 AddOpt(LibFunc::log10, LibFunc::log10f, &UnsafeUnaryDoubleFP);
1418 AddOpt(LibFunc::log1p, LibFunc::log1pf, &UnsafeUnaryDoubleFP);
1419 AddOpt(LibFunc::log2, LibFunc::log2f, &UnsafeUnaryDoubleFP);
1420 AddOpt(LibFunc::logb, LibFunc::logbf, &UnsafeUnaryDoubleFP);
1421 AddOpt(LibFunc::sin, LibFunc::sinf, &UnsafeUnaryDoubleFP);
1422 AddOpt(LibFunc::sinh, LibFunc::sinhf, &UnsafeUnaryDoubleFP);
1423 AddOpt(LibFunc::sqrt, LibFunc::sqrtf, &UnsafeUnaryDoubleFP);
1424 AddOpt(LibFunc::tan, LibFunc::tanf, &UnsafeUnaryDoubleFP);
1425 AddOpt(LibFunc::tanh, LibFunc::tanhf, &UnsafeUnaryDoubleFP);
1428 // Integer Optimizations
1429 Optimizations["ffs"] = &FFS;
1430 Optimizations["ffsl"] = &FFS;
1431 Optimizations["ffsll"] = &FFS;
1432 Optimizations["abs"] = &Abs;
1433 Optimizations["labs"] = &Abs;
1434 Optimizations["llabs"] = &Abs;
1435 Optimizations["isdigit"] = &IsDigit;
1436 Optimizations["isascii"] = &IsAscii;
1437 Optimizations["toascii"] = &ToAscii;
1439 // Formatting and IO Optimizations
1440 Optimizations["sprintf"] = &SPrintF;
1441 Optimizations["printf"] = &PrintF;
1442 AddOpt(LibFunc::fwrite, &FWrite);
1443 AddOpt(LibFunc::fputs, &FPuts);
1444 Optimizations["fprintf"] = &FPrintF;
1445 Optimizations["puts"] = &Puts;
1449 /// runOnFunction - Top level algorithm.
1451 bool SimplifyLibCalls::runOnFunction(Function &F) {
1452 TLI = &getAnalysis<TargetLibraryInfo>();
1454 if (Optimizations.empty())
1455 InitOptimizations();
1457 const DataLayout *TD = getAnalysisIfAvailable<DataLayout>();
1459 IRBuilder<> Builder(F.getContext());
1461 bool Changed = false;
1462 for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
1463 for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ) {
1464 // Ignore non-calls.
1465 CallInst *CI = dyn_cast<CallInst>(I++);
1468 // Ignore indirect calls and calls to non-external functions.
1469 Function *Callee = CI->getCalledFunction();
1470 if (Callee == 0 || !Callee->isDeclaration() ||
1471 !(Callee->hasExternalLinkage() || Callee->hasDLLImportLinkage()))
1474 // Ignore unknown calls.
1475 LibCallOptimization *LCO = Optimizations.lookup(Callee->getName());
1478 // Set the builder to the instruction after the call.
1479 Builder.SetInsertPoint(BB, I);
1481 // Use debug location of CI for all new instructions.
1482 Builder.SetCurrentDebugLocation(CI->getDebugLoc());
1484 // Try to optimize this call.
1485 Value *Result = LCO->OptimizeCall(CI, TD, TLI, Builder);
1486 if (Result == 0) continue;
1488 DEBUG(dbgs() << "SimplifyLibCalls simplified: " << *CI;
1489 dbgs() << " into: " << *Result << "\n");
1491 // Something changed!
1495 // Inspect the instruction after the call (which was potentially just
1499 if (CI != Result && !CI->use_empty()) {
1500 CI->replaceAllUsesWith(Result);
1501 if (!Result->hasName())
1502 Result->takeName(CI);
1504 CI->eraseFromParent();
1510 // Utility methods for doInitialization.
1512 void SimplifyLibCalls::setDoesNotAccessMemory(Function &F) {
1513 if (!F.doesNotAccessMemory()) {
1514 F.setDoesNotAccessMemory();
1519 void SimplifyLibCalls::setOnlyReadsMemory(Function &F) {
1520 if (!F.onlyReadsMemory()) {
1521 F.setOnlyReadsMemory();
1526 void SimplifyLibCalls::setDoesNotThrow(Function &F) {
1527 if (!F.doesNotThrow()) {
1528 F.setDoesNotThrow();
1533 void SimplifyLibCalls::setDoesNotCapture(Function &F, unsigned n) {
1534 if (!F.doesNotCapture(n)) {
1535 F.setDoesNotCapture(n);
1540 void SimplifyLibCalls::setDoesNotAlias(Function &F, unsigned n) {
1541 if (!F.doesNotAlias(n)) {
1542 F.setDoesNotAlias(n);
1549 void SimplifyLibCalls::inferPrototypeAttributes(Function &F) {
1550 FunctionType *FTy = F.getFunctionType();
1552 StringRef Name = F.getName();
1555 if (Name == "strlen") {
1556 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1558 setOnlyReadsMemory(F);
1560 setDoesNotCapture(F, 1);
1561 } else if (Name == "strchr" ||
1562 Name == "strrchr") {
1563 if (FTy->getNumParams() != 2 ||
1564 !FTy->getParamType(0)->isPointerTy() ||
1565 !FTy->getParamType(1)->isIntegerTy())
1567 setOnlyReadsMemory(F);
1569 } else if (Name == "strcpy" ||
1575 Name == "strtoul" ||
1576 Name == "strtoll" ||
1577 Name == "strtold" ||
1578 Name == "strncat" ||
1579 Name == "strncpy" ||
1580 Name == "stpncpy" ||
1581 Name == "strtoull") {
1582 if (FTy->getNumParams() < 2 ||
1583 !FTy->getParamType(1)->isPointerTy())
1586 setDoesNotCapture(F, 2);
1587 } else if (Name == "strxfrm") {
1588 if (FTy->getNumParams() != 3 ||
1589 !FTy->getParamType(0)->isPointerTy() ||
1590 !FTy->getParamType(1)->isPointerTy())
1593 setDoesNotCapture(F, 1);
1594 setDoesNotCapture(F, 2);
1595 } else if (Name == "strcmp" ||
1597 Name == "strncmp" ||
1598 Name == "strcspn" ||
1599 Name == "strcoll" ||
1600 Name == "strcasecmp" ||
1601 Name == "strncasecmp") {
1602 if (FTy->getNumParams() < 2 ||
1603 !FTy->getParamType(0)->isPointerTy() ||
1604 !FTy->getParamType(1)->isPointerTy())
1606 setOnlyReadsMemory(F);
1608 setDoesNotCapture(F, 1);
1609 setDoesNotCapture(F, 2);
1610 } else if (Name == "strstr" ||
1611 Name == "strpbrk") {
1612 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1614 setOnlyReadsMemory(F);
1616 setDoesNotCapture(F, 2);
1617 } else if (Name == "strtok" ||
1618 Name == "strtok_r") {
1619 if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy())
1622 setDoesNotCapture(F, 2);
1623 } else if (Name == "scanf" ||
1625 Name == "setvbuf") {
1626 if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy())
1629 setDoesNotCapture(F, 1);
1630 } else if (Name == "strdup" ||
1631 Name == "strndup") {
1632 if (FTy->getNumParams() < 1 || !FTy->getReturnType()->isPointerTy() ||
1633 !FTy->getParamType(0)->isPointerTy())
1636 setDoesNotAlias(F, 0);
1637 setDoesNotCapture(F, 1);
1638 } else if (Name == "stat" ||
1640 Name == "sprintf" ||
1641 Name == "statvfs") {
1642 if (FTy->getNumParams() < 2 ||
1643 !FTy->getParamType(0)->isPointerTy() ||
1644 !FTy->getParamType(1)->isPointerTy())
1647 setDoesNotCapture(F, 1);
1648 setDoesNotCapture(F, 2);
1649 } else if (Name == "snprintf") {
1650 if (FTy->getNumParams() != 3 ||
1651 !FTy->getParamType(0)->isPointerTy() ||
1652 !FTy->getParamType(2)->isPointerTy())
1655 setDoesNotCapture(F, 1);
1656 setDoesNotCapture(F, 3);
1657 } else if (Name == "setitimer") {
1658 if (FTy->getNumParams() != 3 ||
1659 !FTy->getParamType(1)->isPointerTy() ||
1660 !FTy->getParamType(2)->isPointerTy())
1663 setDoesNotCapture(F, 2);
1664 setDoesNotCapture(F, 3);
1665 } else if (Name == "system") {
1666 if (FTy->getNumParams() != 1 ||
1667 !FTy->getParamType(0)->isPointerTy())
1669 // May throw; "system" is a valid pthread cancellation point.
1670 setDoesNotCapture(F, 1);
1674 if (Name == "malloc") {
1675 if (FTy->getNumParams() != 1 ||
1676 !FTy->getReturnType()->isPointerTy())
1679 setDoesNotAlias(F, 0);
1680 } else if (Name == "memcmp") {
1681 if (FTy->getNumParams() != 3 ||
1682 !FTy->getParamType(0)->isPointerTy() ||
1683 !FTy->getParamType(1)->isPointerTy())
1685 setOnlyReadsMemory(F);
1687 setDoesNotCapture(F, 1);
1688 setDoesNotCapture(F, 2);
1689 } else if (Name == "memchr" ||
1690 Name == "memrchr") {
1691 if (FTy->getNumParams() != 3)
1693 setOnlyReadsMemory(F);
1695 } else if (Name == "modf" ||
1699 Name == "memccpy" ||
1700 Name == "memmove") {
1701 if (FTy->getNumParams() < 2 ||
1702 !FTy->getParamType(1)->isPointerTy())
1705 setDoesNotCapture(F, 2);
1706 } else if (Name == "memalign") {
1707 if (!FTy->getReturnType()->isPointerTy())
1709 setDoesNotAlias(F, 0);
1710 } else if (Name == "mkdir" ||
1712 if (FTy->getNumParams() == 0 ||
1713 !FTy->getParamType(0)->isPointerTy())
1716 setDoesNotCapture(F, 1);
1720 if (Name == "realloc") {
1721 if (FTy->getNumParams() != 2 ||
1722 !FTy->getParamType(0)->isPointerTy() ||
1723 !FTy->getReturnType()->isPointerTy())
1726 setDoesNotAlias(F, 0);
1727 setDoesNotCapture(F, 1);
1728 } else if (Name == "read") {
1729 if (FTy->getNumParams() != 3 ||
1730 !FTy->getParamType(1)->isPointerTy())
1732 // May throw; "read" is a valid pthread cancellation point.
1733 setDoesNotCapture(F, 2);
1734 } else if (Name == "rmdir" ||
1737 Name == "realpath") {
1738 if (FTy->getNumParams() < 1 ||
1739 !FTy->getParamType(0)->isPointerTy())
1742 setDoesNotCapture(F, 1);
1743 } else if (Name == "rename" ||
1744 Name == "readlink") {
1745 if (FTy->getNumParams() < 2 ||
1746 !FTy->getParamType(0)->isPointerTy() ||
1747 !FTy->getParamType(1)->isPointerTy())
1750 setDoesNotCapture(F, 1);
1751 setDoesNotCapture(F, 2);
1755 if (Name == "write") {
1756 if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy())
1758 // May throw; "write" is a valid pthread cancellation point.
1759 setDoesNotCapture(F, 2);
1763 if (Name == "bcopy") {
1764 if (FTy->getNumParams() != 3 ||
1765 !FTy->getParamType(0)->isPointerTy() ||
1766 !FTy->getParamType(1)->isPointerTy())
1769 setDoesNotCapture(F, 1);
1770 setDoesNotCapture(F, 2);
1771 } else if (Name == "bcmp") {
1772 if (FTy->getNumParams() != 3 ||
1773 !FTy->getParamType(0)->isPointerTy() ||
1774 !FTy->getParamType(1)->isPointerTy())
1777 setOnlyReadsMemory(F);
1778 setDoesNotCapture(F, 1);
1779 setDoesNotCapture(F, 2);
1780 } else if (Name == "bzero") {
1781 if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
1784 setDoesNotCapture(F, 1);
1788 if (Name == "calloc") {
1789 if (FTy->getNumParams() != 2 ||
1790 !FTy->getReturnType()->isPointerTy())
1793 setDoesNotAlias(F, 0);
1794 } else if (Name == "chmod" ||
1796 Name == "ctermid" ||
1797 Name == "clearerr" ||
1798 Name == "closedir") {
1799 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
1802 setDoesNotCapture(F, 1);
1806 if (Name == "atoi" ||
1810 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1813 setOnlyReadsMemory(F);
1814 setDoesNotCapture(F, 1);
1815 } else if (Name == "access") {
1816 if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
1819 setDoesNotCapture(F, 1);
1823 if (Name == "fopen") {
1824 if (FTy->getNumParams() != 2 ||
1825 !FTy->getReturnType()->isPointerTy() ||
1826 !FTy->getParamType(0)->isPointerTy() ||
1827 !FTy->getParamType(1)->isPointerTy())
1830 setDoesNotAlias(F, 0);
1831 setDoesNotCapture(F, 1);
1832 setDoesNotCapture(F, 2);
1833 } else if (Name == "fdopen") {
1834 if (FTy->getNumParams() != 2 ||
1835 !FTy->getReturnType()->isPointerTy() ||
1836 !FTy->getParamType(1)->isPointerTy())
1839 setDoesNotAlias(F, 0);
1840 setDoesNotCapture(F, 2);
1841 } else if (Name == "feof" ||
1851 Name == "fsetpos" ||
1852 Name == "flockfile" ||
1853 Name == "funlockfile" ||
1854 Name == "ftrylockfile") {
1855 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
1858 setDoesNotCapture(F, 1);
1859 } else if (Name == "ferror") {
1860 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1863 setDoesNotCapture(F, 1);
1864 setOnlyReadsMemory(F);
1865 } else if (Name == "fputc" ||
1870 Name == "fstatvfs") {
1871 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1874 setDoesNotCapture(F, 2);
1875 } else if (Name == "fgets") {
1876 if (FTy->getNumParams() != 3 ||
1877 !FTy->getParamType(0)->isPointerTy() ||
1878 !FTy->getParamType(2)->isPointerTy())
1881 setDoesNotCapture(F, 3);
1882 } else if (Name == "fread" ||
1884 if (FTy->getNumParams() != 4 ||
1885 !FTy->getParamType(0)->isPointerTy() ||
1886 !FTy->getParamType(3)->isPointerTy())
1889 setDoesNotCapture(F, 1);
1890 setDoesNotCapture(F, 4);
1891 } else if (Name == "fputs" ||
1893 Name == "fprintf" ||
1894 Name == "fgetpos") {
1895 if (FTy->getNumParams() < 2 ||
1896 !FTy->getParamType(0)->isPointerTy() ||
1897 !FTy->getParamType(1)->isPointerTy())
1900 setDoesNotCapture(F, 1);
1901 setDoesNotCapture(F, 2);
1905 if (Name == "getc" ||
1906 Name == "getlogin_r" ||
1907 Name == "getc_unlocked") {
1908 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
1911 setDoesNotCapture(F, 1);
1912 } else if (Name == "getenv") {
1913 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1916 setOnlyReadsMemory(F);
1917 setDoesNotCapture(F, 1);
1918 } else if (Name == "gets" ||
1919 Name == "getchar") {
1921 } else if (Name == "getitimer") {
1922 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1925 setDoesNotCapture(F, 2);
1926 } else if (Name == "getpwnam") {
1927 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1930 setDoesNotCapture(F, 1);
1934 if (Name == "ungetc") {
1935 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1938 setDoesNotCapture(F, 2);
1939 } else if (Name == "uname" ||
1941 Name == "unsetenv") {
1942 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1945 setDoesNotCapture(F, 1);
1946 } else if (Name == "utime" ||
1948 if (FTy->getNumParams() != 2 ||
1949 !FTy->getParamType(0)->isPointerTy() ||
1950 !FTy->getParamType(1)->isPointerTy())
1953 setDoesNotCapture(F, 1);
1954 setDoesNotCapture(F, 2);
1958 if (Name == "putc") {
1959 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1962 setDoesNotCapture(F, 2);
1963 } else if (Name == "puts" ||
1966 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1969 setDoesNotCapture(F, 1);
1970 } else if (Name == "pread" ||
1972 if (FTy->getNumParams() != 4 || !FTy->getParamType(1)->isPointerTy())
1974 // May throw; these are valid pthread cancellation points.
1975 setDoesNotCapture(F, 2);
1976 } else if (Name == "putchar") {
1978 } else if (Name == "popen") {
1979 if (FTy->getNumParams() != 2 ||
1980 !FTy->getReturnType()->isPointerTy() ||
1981 !FTy->getParamType(0)->isPointerTy() ||
1982 !FTy->getParamType(1)->isPointerTy())
1985 setDoesNotAlias(F, 0);
1986 setDoesNotCapture(F, 1);
1987 setDoesNotCapture(F, 2);
1988 } else if (Name == "pclose") {
1989 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1992 setDoesNotCapture(F, 1);
1996 if (Name == "vscanf") {
1997 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2000 setDoesNotCapture(F, 1);
2001 } else if (Name == "vsscanf" ||
2002 Name == "vfscanf") {
2003 if (FTy->getNumParams() != 3 ||
2004 !FTy->getParamType(1)->isPointerTy() ||
2005 !FTy->getParamType(2)->isPointerTy())
2008 setDoesNotCapture(F, 1);
2009 setDoesNotCapture(F, 2);
2010 } else if (Name == "valloc") {
2011 if (!FTy->getReturnType()->isPointerTy())
2014 setDoesNotAlias(F, 0);
2015 } else if (Name == "vprintf") {
2016 if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
2019 setDoesNotCapture(F, 1);
2020 } else if (Name == "vfprintf" ||
2021 Name == "vsprintf") {
2022 if (FTy->getNumParams() != 3 ||
2023 !FTy->getParamType(0)->isPointerTy() ||
2024 !FTy->getParamType(1)->isPointerTy())
2027 setDoesNotCapture(F, 1);
2028 setDoesNotCapture(F, 2);
2029 } else if (Name == "vsnprintf") {
2030 if (FTy->getNumParams() != 4 ||
2031 !FTy->getParamType(0)->isPointerTy() ||
2032 !FTy->getParamType(2)->isPointerTy())
2035 setDoesNotCapture(F, 1);
2036 setDoesNotCapture(F, 3);
2040 if (Name == "open") {
2041 if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
2043 // May throw; "open" is a valid pthread cancellation point.
2044 setDoesNotCapture(F, 1);
2045 } else if (Name == "opendir") {
2046 if (FTy->getNumParams() != 1 ||
2047 !FTy->getReturnType()->isPointerTy() ||
2048 !FTy->getParamType(0)->isPointerTy())
2051 setDoesNotAlias(F, 0);
2052 setDoesNotCapture(F, 1);
2056 if (Name == "tmpfile") {
2057 if (!FTy->getReturnType()->isPointerTy())
2060 setDoesNotAlias(F, 0);
2061 } else if (Name == "times") {
2062 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2065 setDoesNotCapture(F, 1);
2069 if (Name == "htonl" ||
2072 setDoesNotAccessMemory(F);
2076 if (Name == "ntohl" ||
2079 setDoesNotAccessMemory(F);
2083 if (Name == "lstat") {
2084 if (FTy->getNumParams() != 2 ||
2085 !FTy->getParamType(0)->isPointerTy() ||
2086 !FTy->getParamType(1)->isPointerTy())
2089 setDoesNotCapture(F, 1);
2090 setDoesNotCapture(F, 2);
2091 } else if (Name == "lchown") {
2092 if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy())
2095 setDoesNotCapture(F, 1);
2099 if (Name == "qsort") {
2100 if (FTy->getNumParams() != 4 || !FTy->getParamType(3)->isPointerTy())
2102 // May throw; places call through function pointer.
2103 setDoesNotCapture(F, 4);
2107 if (Name == "__strdup" ||
2108 Name == "__strndup") {
2109 if (FTy->getNumParams() < 1 ||
2110 !FTy->getReturnType()->isPointerTy() ||
2111 !FTy->getParamType(0)->isPointerTy())
2114 setDoesNotAlias(F, 0);
2115 setDoesNotCapture(F, 1);
2116 } else if (Name == "__strtok_r") {
2117 if (FTy->getNumParams() != 3 ||
2118 !FTy->getParamType(1)->isPointerTy())
2121 setDoesNotCapture(F, 2);
2122 } else if (Name == "_IO_getc") {
2123 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2126 setDoesNotCapture(F, 1);
2127 } else if (Name == "_IO_putc") {
2128 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2131 setDoesNotCapture(F, 2);
2135 if (Name == "\1__isoc99_scanf") {
2136 if (FTy->getNumParams() < 1 ||
2137 !FTy->getParamType(0)->isPointerTy())
2140 setDoesNotCapture(F, 1);
2141 } else if (Name == "\1stat64" ||
2142 Name == "\1lstat64" ||
2143 Name == "\1statvfs64" ||
2144 Name == "\1__isoc99_sscanf") {
2145 if (FTy->getNumParams() < 1 ||
2146 !FTy->getParamType(0)->isPointerTy() ||
2147 !FTy->getParamType(1)->isPointerTy())
2150 setDoesNotCapture(F, 1);
2151 setDoesNotCapture(F, 2);
2152 } else if (Name == "\1fopen64") {
2153 if (FTy->getNumParams() != 2 ||
2154 !FTy->getReturnType()->isPointerTy() ||
2155 !FTy->getParamType(0)->isPointerTy() ||
2156 !FTy->getParamType(1)->isPointerTy())
2159 setDoesNotAlias(F, 0);
2160 setDoesNotCapture(F, 1);
2161 setDoesNotCapture(F, 2);
2162 } else if (Name == "\1fseeko64" ||
2163 Name == "\1ftello64") {
2164 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
2167 setDoesNotCapture(F, 1);
2168 } else if (Name == "\1tmpfile64") {
2169 if (!FTy->getReturnType()->isPointerTy())
2172 setDoesNotAlias(F, 0);
2173 } else if (Name == "\1fstat64" ||
2174 Name == "\1fstatvfs64") {
2175 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2178 setDoesNotCapture(F, 2);
2179 } else if (Name == "\1open64") {
2180 if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
2182 // May throw; "open" is a valid pthread cancellation point.
2183 setDoesNotCapture(F, 1);
2189 /// doInitialization - Add attributes to well-known functions.
2191 bool SimplifyLibCalls::doInitialization(Module &M) {
2193 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
2195 if (F.isDeclaration() && F.hasName())
2196 inferPrototypeAttributes(F);
2202 // Additional cases that we need to add to this file:
2205 // * cbrt(expN(X)) -> expN(x/3)
2206 // * cbrt(sqrt(x)) -> pow(x,1/6)
2207 // * cbrt(sqrt(x)) -> pow(x,1/9)
2210 // * exp(log(x)) -> x
2213 // * log(exp(x)) -> x
2214 // * log(x**y) -> y*log(x)
2215 // * log(exp(y)) -> y*log(e)
2216 // * log(exp2(y)) -> y*log(2)
2217 // * log(exp10(y)) -> y*log(10)
2218 // * log(sqrt(x)) -> 0.5*log(x)
2219 // * log(pow(x,y)) -> y*log(x)
2221 // lround, lroundf, lroundl:
2222 // * lround(cnst) -> cnst'
2225 // * pow(exp(x),y) -> exp(x*y)
2226 // * pow(sqrt(x),y) -> pow(x,y*0.5)
2227 // * pow(pow(x,y),z)-> pow(x,y*z)
2229 // round, roundf, roundl:
2230 // * round(cnst) -> cnst'
2233 // * signbit(cnst) -> cnst'
2234 // * signbit(nncst) -> 0 (if pstv is a non-negative constant)
2236 // sqrt, sqrtf, sqrtl:
2237 // * sqrt(expN(x)) -> expN(x*0.5)
2238 // * sqrt(Nroot(x)) -> pow(x,1/(2*N))
2239 // * sqrt(pow(x,y)) -> pow(|x|,y*0.5)
2242 // * strchr(p, 0) -> strlen(p)
2244 // * tan(atan(x)) -> x
2246 // trunc, truncf, truncl:
2247 // * trunc(cnst) -> cnst'