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 Attributes::Builder B;
352 B.addAttribute(Attributes::NoCapture);
353 CI->addAttribute(1, Attributes::get(Callee->getContext(), B));
360 //===---------------------------------------===//
361 // 'strspn' Optimizations
363 struct StrSpnOpt : public LibCallOptimization {
364 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
365 FunctionType *FT = Callee->getFunctionType();
366 if (FT->getNumParams() != 2 ||
367 FT->getParamType(0) != B.getInt8PtrTy() ||
368 FT->getParamType(1) != FT->getParamType(0) ||
369 !FT->getReturnType()->isIntegerTy())
373 bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
374 bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
376 // strspn(s, "") -> 0
377 // strspn("", s) -> 0
378 if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
379 return Constant::getNullValue(CI->getType());
382 if (HasS1 && HasS2) {
383 size_t Pos = S1.find_first_not_of(S2);
384 if (Pos == StringRef::npos) Pos = S1.size();
385 return ConstantInt::get(CI->getType(), Pos);
392 //===---------------------------------------===//
393 // 'strcspn' Optimizations
395 struct StrCSpnOpt : public LibCallOptimization {
396 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
397 FunctionType *FT = Callee->getFunctionType();
398 if (FT->getNumParams() != 2 ||
399 FT->getParamType(0) != B.getInt8PtrTy() ||
400 FT->getParamType(1) != FT->getParamType(0) ||
401 !FT->getReturnType()->isIntegerTy())
405 bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
406 bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
408 // strcspn("", s) -> 0
409 if (HasS1 && S1.empty())
410 return Constant::getNullValue(CI->getType());
413 if (HasS1 && HasS2) {
414 size_t Pos = S1.find_first_of(S2);
415 if (Pos == StringRef::npos) Pos = S1.size();
416 return ConstantInt::get(CI->getType(), Pos);
419 // strcspn(s, "") -> strlen(s)
420 if (TD && HasS2 && S2.empty())
421 return EmitStrLen(CI->getArgOperand(0), B, TD, TLI);
427 //===---------------------------------------===//
428 // 'strstr' Optimizations
430 struct StrStrOpt : public LibCallOptimization {
431 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
432 FunctionType *FT = Callee->getFunctionType();
433 if (FT->getNumParams() != 2 ||
434 !FT->getParamType(0)->isPointerTy() ||
435 !FT->getParamType(1)->isPointerTy() ||
436 !FT->getReturnType()->isPointerTy())
439 // fold strstr(x, x) -> x.
440 if (CI->getArgOperand(0) == CI->getArgOperand(1))
441 return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
443 // fold strstr(a, b) == a -> strncmp(a, b, strlen(b)) == 0
444 if (TD && IsOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) {
445 Value *StrLen = EmitStrLen(CI->getArgOperand(1), B, TD, TLI);
448 Value *StrNCmp = EmitStrNCmp(CI->getArgOperand(0), CI->getArgOperand(1),
452 for (Value::use_iterator UI = CI->use_begin(), UE = CI->use_end();
454 ICmpInst *Old = cast<ICmpInst>(*UI++);
455 Value *Cmp = B.CreateICmp(Old->getPredicate(), StrNCmp,
456 ConstantInt::getNullValue(StrNCmp->getType()),
458 Old->replaceAllUsesWith(Cmp);
459 Old->eraseFromParent();
464 // See if either input string is a constant string.
465 StringRef SearchStr, ToFindStr;
466 bool HasStr1 = getConstantStringInfo(CI->getArgOperand(0), SearchStr);
467 bool HasStr2 = getConstantStringInfo(CI->getArgOperand(1), ToFindStr);
469 // fold strstr(x, "") -> x.
470 if (HasStr2 && ToFindStr.empty())
471 return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
473 // If both strings are known, constant fold it.
474 if (HasStr1 && HasStr2) {
475 std::string::size_type Offset = SearchStr.find(ToFindStr);
477 if (Offset == StringRef::npos) // strstr("foo", "bar") -> null
478 return Constant::getNullValue(CI->getType());
480 // strstr("abcd", "bc") -> gep((char*)"abcd", 1)
481 Value *Result = CastToCStr(CI->getArgOperand(0), B);
482 Result = B.CreateConstInBoundsGEP1_64(Result, Offset, "strstr");
483 return B.CreateBitCast(Result, CI->getType());
486 // fold strstr(x, "y") -> strchr(x, 'y').
487 if (HasStr2 && ToFindStr.size() == 1) {
488 Value *StrChr= EmitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TD, TLI);
489 return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : 0;
496 //===---------------------------------------===//
497 // 'memcmp' Optimizations
499 struct MemCmpOpt : public LibCallOptimization {
500 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
501 FunctionType *FT = Callee->getFunctionType();
502 if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
503 !FT->getParamType(1)->isPointerTy() ||
504 !FT->getReturnType()->isIntegerTy(32))
507 Value *LHS = CI->getArgOperand(0), *RHS = CI->getArgOperand(1);
509 if (LHS == RHS) // memcmp(s,s,x) -> 0
510 return Constant::getNullValue(CI->getType());
512 // Make sure we have a constant length.
513 ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
515 uint64_t Len = LenC->getZExtValue();
517 if (Len == 0) // memcmp(s1,s2,0) -> 0
518 return Constant::getNullValue(CI->getType());
520 // memcmp(S1,S2,1) -> *(unsigned char*)LHS - *(unsigned char*)RHS
522 Value *LHSV = B.CreateZExt(B.CreateLoad(CastToCStr(LHS, B), "lhsc"),
523 CI->getType(), "lhsv");
524 Value *RHSV = B.CreateZExt(B.CreateLoad(CastToCStr(RHS, B), "rhsc"),
525 CI->getType(), "rhsv");
526 return B.CreateSub(LHSV, RHSV, "chardiff");
529 // Constant folding: memcmp(x, y, l) -> cnst (all arguments are constant)
530 StringRef LHSStr, RHSStr;
531 if (getConstantStringInfo(LHS, LHSStr) &&
532 getConstantStringInfo(RHS, RHSStr)) {
533 // Make sure we're not reading out-of-bounds memory.
534 if (Len > LHSStr.size() || Len > RHSStr.size())
536 uint64_t Ret = memcmp(LHSStr.data(), RHSStr.data(), Len);
537 return ConstantInt::get(CI->getType(), Ret);
544 //===---------------------------------------===//
545 // 'memcpy' Optimizations
547 struct MemCpyOpt : public LibCallOptimization {
548 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
549 // These optimizations require DataLayout.
552 FunctionType *FT = Callee->getFunctionType();
553 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
554 !FT->getParamType(0)->isPointerTy() ||
555 !FT->getParamType(1)->isPointerTy() ||
556 FT->getParamType(2) != TD->getIntPtrType(*Context))
559 // memcpy(x, y, n) -> llvm.memcpy(x, y, n, 1)
560 B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
561 CI->getArgOperand(2), 1);
562 return CI->getArgOperand(0);
566 //===---------------------------------------===//
567 // 'memmove' Optimizations
569 struct MemMoveOpt : public LibCallOptimization {
570 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
571 // These optimizations require DataLayout.
574 FunctionType *FT = Callee->getFunctionType();
575 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
576 !FT->getParamType(0)->isPointerTy() ||
577 !FT->getParamType(1)->isPointerTy() ||
578 FT->getParamType(2) != TD->getIntPtrType(*Context))
581 // memmove(x, y, n) -> llvm.memmove(x, y, n, 1)
582 B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
583 CI->getArgOperand(2), 1);
584 return CI->getArgOperand(0);
588 //===---------------------------------------===//
589 // 'memset' Optimizations
591 struct MemSetOpt : public LibCallOptimization {
592 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
593 // These optimizations require DataLayout.
596 FunctionType *FT = Callee->getFunctionType();
597 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
598 !FT->getParamType(0)->isPointerTy() ||
599 !FT->getParamType(1)->isIntegerTy() ||
600 FT->getParamType(2) != TD->getIntPtrType(*Context))
603 // memset(p, v, n) -> llvm.memset(p, v, n, 1)
604 Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
605 B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
606 return CI->getArgOperand(0);
610 //===----------------------------------------------------------------------===//
611 // Math Library Optimizations
612 //===----------------------------------------------------------------------===//
614 //===---------------------------------------===//
615 // Double -> Float Shrinking Optimizations for Unary Functions like 'floor'
617 struct UnaryDoubleFPOpt : public LibCallOptimization {
619 UnaryDoubleFPOpt(bool CheckReturnType): CheckRetType(CheckReturnType) {}
620 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
621 FunctionType *FT = Callee->getFunctionType();
622 if (FT->getNumParams() != 1 || !FT->getReturnType()->isDoubleTy() ||
623 !FT->getParamType(0)->isDoubleTy())
627 // Check if all the uses for function like 'sin' are converted to float.
628 for (Value::use_iterator UseI = CI->use_begin(); UseI != CI->use_end();
630 FPTruncInst *Cast = dyn_cast<FPTruncInst>(*UseI);
631 if (Cast == 0 || !Cast->getType()->isFloatTy())
636 // If this is something like 'floor((double)floatval)', convert to floorf.
637 FPExtInst *Cast = dyn_cast<FPExtInst>(CI->getArgOperand(0));
638 if (Cast == 0 || !Cast->getOperand(0)->getType()->isFloatTy())
641 // floor((double)floatval) -> (double)floorf(floatval)
642 Value *V = Cast->getOperand(0);
643 V = EmitUnaryFloatFnCall(V, Callee->getName(), B, Callee->getAttributes());
644 return B.CreateFPExt(V, B.getDoubleTy());
648 //===---------------------------------------===//
649 // 'cos*' Optimizations
650 struct CosOpt : public LibCallOptimization {
651 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
653 if (UnsafeFPShrink && Callee->getName() == "cos" &&
654 TLI->has(LibFunc::cosf)) {
655 UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
656 Ret = UnsafeUnaryDoubleFP.CallOptimizer(Callee, CI, B);
659 FunctionType *FT = Callee->getFunctionType();
660 // Just make sure this has 1 argument of FP type, which matches the
662 if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
663 !FT->getParamType(0)->isFloatingPointTy())
667 Value *Op1 = CI->getArgOperand(0);
668 if (BinaryOperator::isFNeg(Op1)) {
669 BinaryOperator *BinExpr = cast<BinaryOperator>(Op1);
670 return B.CreateCall(Callee, BinExpr->getOperand(1), "cos");
676 //===---------------------------------------===//
677 // 'pow*' Optimizations
679 struct PowOpt : public LibCallOptimization {
680 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
682 if (UnsafeFPShrink && Callee->getName() == "pow" &&
683 TLI->has(LibFunc::powf)) {
684 UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
685 Ret = UnsafeUnaryDoubleFP.CallOptimizer(Callee, CI, B);
688 FunctionType *FT = Callee->getFunctionType();
689 // Just make sure this has 2 arguments of the same FP type, which match the
691 if (FT->getNumParams() != 2 || FT->getReturnType() != FT->getParamType(0) ||
692 FT->getParamType(0) != FT->getParamType(1) ||
693 !FT->getParamType(0)->isFloatingPointTy())
696 Value *Op1 = CI->getArgOperand(0), *Op2 = CI->getArgOperand(1);
697 if (ConstantFP *Op1C = dyn_cast<ConstantFP>(Op1)) {
698 if (Op1C->isExactlyValue(1.0)) // pow(1.0, x) -> 1.0
700 if (Op1C->isExactlyValue(2.0)) // pow(2.0, x) -> exp2(x)
701 return EmitUnaryFloatFnCall(Op2, "exp2", B, Callee->getAttributes());
704 ConstantFP *Op2C = dyn_cast<ConstantFP>(Op2);
705 if (Op2C == 0) return Ret;
707 if (Op2C->getValueAPF().isZero()) // pow(x, 0.0) -> 1.0
708 return ConstantFP::get(CI->getType(), 1.0);
710 if (Op2C->isExactlyValue(0.5)) {
711 // Expand pow(x, 0.5) to (x == -infinity ? +infinity : fabs(sqrt(x))).
712 // This is faster than calling pow, and still handles negative zero
713 // and negative infinity correctly.
714 // TODO: In fast-math mode, this could be just sqrt(x).
715 // TODO: In finite-only mode, this could be just fabs(sqrt(x)).
716 Value *Inf = ConstantFP::getInfinity(CI->getType());
717 Value *NegInf = ConstantFP::getInfinity(CI->getType(), true);
718 Value *Sqrt = EmitUnaryFloatFnCall(Op1, "sqrt", B,
719 Callee->getAttributes());
720 Value *FAbs = EmitUnaryFloatFnCall(Sqrt, "fabs", B,
721 Callee->getAttributes());
722 Value *FCmp = B.CreateFCmpOEQ(Op1, NegInf);
723 Value *Sel = B.CreateSelect(FCmp, Inf, FAbs);
727 if (Op2C->isExactlyValue(1.0)) // pow(x, 1.0) -> x
729 if (Op2C->isExactlyValue(2.0)) // pow(x, 2.0) -> x*x
730 return B.CreateFMul(Op1, Op1, "pow2");
731 if (Op2C->isExactlyValue(-1.0)) // pow(x, -1.0) -> 1.0/x
732 return B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0),
738 //===---------------------------------------===//
739 // 'exp2' Optimizations
741 struct Exp2Opt : public LibCallOptimization {
742 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
744 if (UnsafeFPShrink && Callee->getName() == "exp2" &&
745 TLI->has(LibFunc::exp2)) {
746 UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
747 Ret = UnsafeUnaryDoubleFP.CallOptimizer(Callee, CI, B);
750 FunctionType *FT = Callee->getFunctionType();
751 // Just make sure this has 1 argument of FP type, which matches the
753 if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
754 !FT->getParamType(0)->isFloatingPointTy())
757 Value *Op = CI->getArgOperand(0);
758 // Turn exp2(sitofp(x)) -> ldexp(1.0, sext(x)) if sizeof(x) <= 32
759 // Turn exp2(uitofp(x)) -> ldexp(1.0, zext(x)) if sizeof(x) < 32
761 if (SIToFPInst *OpC = dyn_cast<SIToFPInst>(Op)) {
762 if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() <= 32)
763 LdExpArg = B.CreateSExt(OpC->getOperand(0), B.getInt32Ty());
764 } else if (UIToFPInst *OpC = dyn_cast<UIToFPInst>(Op)) {
765 if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() < 32)
766 LdExpArg = B.CreateZExt(OpC->getOperand(0), B.getInt32Ty());
771 if (Op->getType()->isFloatTy())
773 else if (Op->getType()->isDoubleTy())
778 Constant *One = ConstantFP::get(*Context, APFloat(1.0f));
779 if (!Op->getType()->isFloatTy())
780 One = ConstantExpr::getFPExtend(One, Op->getType());
782 Module *M = Caller->getParent();
783 Value *Callee = M->getOrInsertFunction(Name, Op->getType(),
785 B.getInt32Ty(), NULL);
786 CallInst *CI = B.CreateCall2(Callee, One, LdExpArg);
787 if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts()))
788 CI->setCallingConv(F->getCallingConv());
796 //===----------------------------------------------------------------------===//
797 // Integer Optimizations
798 //===----------------------------------------------------------------------===//
800 //===---------------------------------------===//
801 // 'ffs*' Optimizations
803 struct FFSOpt : public LibCallOptimization {
804 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
805 FunctionType *FT = Callee->getFunctionType();
806 // Just make sure this has 2 arguments of the same FP type, which match the
808 if (FT->getNumParams() != 1 ||
809 !FT->getReturnType()->isIntegerTy(32) ||
810 !FT->getParamType(0)->isIntegerTy())
813 Value *Op = CI->getArgOperand(0);
816 if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
817 if (CI->getValue() == 0) // ffs(0) -> 0.
818 return Constant::getNullValue(CI->getType());
819 // ffs(c) -> cttz(c)+1
820 return B.getInt32(CI->getValue().countTrailingZeros() + 1);
823 // ffs(x) -> x != 0 ? (i32)llvm.cttz(x)+1 : 0
824 Type *ArgType = Op->getType();
825 Value *F = Intrinsic::getDeclaration(Callee->getParent(),
826 Intrinsic::cttz, ArgType);
827 Value *V = B.CreateCall2(F, Op, B.getFalse(), "cttz");
828 V = B.CreateAdd(V, ConstantInt::get(V->getType(), 1));
829 V = B.CreateIntCast(V, B.getInt32Ty(), false);
831 Value *Cond = B.CreateICmpNE(Op, Constant::getNullValue(ArgType));
832 return B.CreateSelect(Cond, V, B.getInt32(0));
836 //===---------------------------------------===//
837 // 'isdigit' Optimizations
839 struct IsDigitOpt : public LibCallOptimization {
840 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
841 FunctionType *FT = Callee->getFunctionType();
842 // We require integer(i32)
843 if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
844 !FT->getParamType(0)->isIntegerTy(32))
847 // isdigit(c) -> (c-'0') <u 10
848 Value *Op = CI->getArgOperand(0);
849 Op = B.CreateSub(Op, B.getInt32('0'), "isdigittmp");
850 Op = B.CreateICmpULT(Op, B.getInt32(10), "isdigit");
851 return B.CreateZExt(Op, CI->getType());
855 //===---------------------------------------===//
856 // 'isascii' Optimizations
858 struct IsAsciiOpt : public LibCallOptimization {
859 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
860 FunctionType *FT = Callee->getFunctionType();
861 // We require integer(i32)
862 if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
863 !FT->getParamType(0)->isIntegerTy(32))
866 // isascii(c) -> c <u 128
867 Value *Op = CI->getArgOperand(0);
868 Op = B.CreateICmpULT(Op, B.getInt32(128), "isascii");
869 return B.CreateZExt(Op, CI->getType());
873 //===---------------------------------------===//
874 // 'abs', 'labs', 'llabs' Optimizations
876 struct AbsOpt : public LibCallOptimization {
877 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
878 FunctionType *FT = Callee->getFunctionType();
879 // We require integer(integer) where the types agree.
880 if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
881 FT->getParamType(0) != FT->getReturnType())
884 // abs(x) -> x >s -1 ? x : -x
885 Value *Op = CI->getArgOperand(0);
886 Value *Pos = B.CreateICmpSGT(Op, Constant::getAllOnesValue(Op->getType()),
888 Value *Neg = B.CreateNeg(Op, "neg");
889 return B.CreateSelect(Pos, Op, Neg);
894 //===---------------------------------------===//
895 // 'toascii' Optimizations
897 struct ToAsciiOpt : public LibCallOptimization {
898 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
899 FunctionType *FT = Callee->getFunctionType();
900 // We require i32(i32)
901 if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
902 !FT->getParamType(0)->isIntegerTy(32))
905 // isascii(c) -> c & 0x7f
906 return B.CreateAnd(CI->getArgOperand(0),
907 ConstantInt::get(CI->getType(),0x7F));
911 //===----------------------------------------------------------------------===//
912 // Formatting and IO Optimizations
913 //===----------------------------------------------------------------------===//
915 //===---------------------------------------===//
916 // 'printf' Optimizations
918 struct PrintFOpt : public LibCallOptimization {
919 Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
921 // Check for a fixed format string.
923 if (!getConstantStringInfo(CI->getArgOperand(0), FormatStr))
926 // Empty format string -> noop.
927 if (FormatStr.empty()) // Tolerate printf's declared void.
928 return CI->use_empty() ? (Value*)CI :
929 ConstantInt::get(CI->getType(), 0);
931 // Do not do any of the following transformations if the printf return value
932 // is used, in general the printf return value is not compatible with either
933 // putchar() or puts().
934 if (!CI->use_empty())
937 // printf("x") -> putchar('x'), even for '%'.
938 if (FormatStr.size() == 1) {
939 Value *Res = EmitPutChar(B.getInt32(FormatStr[0]), B, TD, TLI);
940 if (CI->use_empty() || !Res) return Res;
941 return B.CreateIntCast(Res, CI->getType(), true);
944 // printf("foo\n") --> puts("foo")
945 if (FormatStr[FormatStr.size()-1] == '\n' &&
946 FormatStr.find('%') == std::string::npos) { // no format characters.
947 // Create a string literal with no \n on it. We expect the constant merge
948 // pass to be run after this pass, to merge duplicate strings.
949 FormatStr = FormatStr.drop_back();
950 Value *GV = B.CreateGlobalString(FormatStr, "str");
951 Value *NewCI = EmitPutS(GV, B, TD, TLI);
952 return (CI->use_empty() || !NewCI) ?
954 ConstantInt::get(CI->getType(), FormatStr.size()+1);
957 // Optimize specific format strings.
958 // printf("%c", chr) --> putchar(chr)
959 if (FormatStr == "%c" && CI->getNumArgOperands() > 1 &&
960 CI->getArgOperand(1)->getType()->isIntegerTy()) {
961 Value *Res = EmitPutChar(CI->getArgOperand(1), B, TD, TLI);
963 if (CI->use_empty() || !Res) return Res;
964 return B.CreateIntCast(Res, CI->getType(), true);
967 // printf("%s\n", str) --> puts(str)
968 if (FormatStr == "%s\n" && CI->getNumArgOperands() > 1 &&
969 CI->getArgOperand(1)->getType()->isPointerTy()) {
970 return EmitPutS(CI->getArgOperand(1), B, TD, TLI);
975 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
976 // Require one fixed pointer argument and an integer/void result.
977 FunctionType *FT = Callee->getFunctionType();
978 if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
979 !(FT->getReturnType()->isIntegerTy() ||
980 FT->getReturnType()->isVoidTy()))
983 if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
987 // printf(format, ...) -> iprintf(format, ...) if no floating point
989 if (TLI->has(LibFunc::iprintf) && !CallHasFloatingPointArgument(CI)) {
990 Module *M = B.GetInsertBlock()->getParent()->getParent();
991 Constant *IPrintFFn =
992 M->getOrInsertFunction("iprintf", FT, Callee->getAttributes());
993 CallInst *New = cast<CallInst>(CI->clone());
994 New->setCalledFunction(IPrintFFn);
1002 //===---------------------------------------===//
1003 // 'sprintf' Optimizations
1005 struct SPrintFOpt : public LibCallOptimization {
1006 Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
1008 // Check for a fixed format string.
1009 StringRef FormatStr;
1010 if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
1013 // If we just have a format string (nothing else crazy) transform it.
1014 if (CI->getNumArgOperands() == 2) {
1015 // Make sure there's no % in the constant array. We could try to handle
1016 // %% -> % in the future if we cared.
1017 for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
1018 if (FormatStr[i] == '%')
1019 return 0; // we found a format specifier, bail out.
1021 // These optimizations require DataLayout.
1024 // sprintf(str, fmt) -> llvm.memcpy(str, fmt, strlen(fmt)+1, 1)
1025 B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
1026 ConstantInt::get(TD->getIntPtrType(*Context), // Copy the
1027 FormatStr.size() + 1), 1); // nul byte.
1028 return ConstantInt::get(CI->getType(), FormatStr.size());
1031 // The remaining optimizations require the format string to be "%s" or "%c"
1032 // and have an extra operand.
1033 if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
1034 CI->getNumArgOperands() < 3)
1037 // Decode the second character of the format string.
1038 if (FormatStr[1] == 'c') {
1039 // sprintf(dst, "%c", chr) --> *(i8*)dst = chr; *((i8*)dst+1) = 0
1040 if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
1041 Value *V = B.CreateTrunc(CI->getArgOperand(2), B.getInt8Ty(), "char");
1042 Value *Ptr = CastToCStr(CI->getArgOperand(0), B);
1043 B.CreateStore(V, Ptr);
1044 Ptr = B.CreateGEP(Ptr, B.getInt32(1), "nul");
1045 B.CreateStore(B.getInt8(0), Ptr);
1047 return ConstantInt::get(CI->getType(), 1);
1050 if (FormatStr[1] == 's') {
1051 // These optimizations require DataLayout.
1054 // sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1)
1055 if (!CI->getArgOperand(2)->getType()->isPointerTy()) return 0;
1057 Value *Len = EmitStrLen(CI->getArgOperand(2), B, TD, TLI);
1060 Value *IncLen = B.CreateAdd(Len,
1061 ConstantInt::get(Len->getType(), 1),
1063 B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(2), IncLen, 1);
1065 // The sprintf result is the unincremented number of bytes in the string.
1066 return B.CreateIntCast(Len, CI->getType(), false);
1071 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1072 // Require two fixed pointer arguments and an integer result.
1073 FunctionType *FT = Callee->getFunctionType();
1074 if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
1075 !FT->getParamType(1)->isPointerTy() ||
1076 !FT->getReturnType()->isIntegerTy())
1079 if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
1083 // sprintf(str, format, ...) -> siprintf(str, format, ...) if no floating
1085 if (TLI->has(LibFunc::siprintf) && !CallHasFloatingPointArgument(CI)) {
1086 Module *M = B.GetInsertBlock()->getParent()->getParent();
1087 Constant *SIPrintFFn =
1088 M->getOrInsertFunction("siprintf", FT, Callee->getAttributes());
1089 CallInst *New = cast<CallInst>(CI->clone());
1090 New->setCalledFunction(SIPrintFFn);
1098 //===---------------------------------------===//
1099 // 'fwrite' Optimizations
1101 struct FWriteOpt : public LibCallOptimization {
1102 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1103 // Require a pointer, an integer, an integer, a pointer, returning integer.
1104 FunctionType *FT = Callee->getFunctionType();
1105 if (FT->getNumParams() != 4 || !FT->getParamType(0)->isPointerTy() ||
1106 !FT->getParamType(1)->isIntegerTy() ||
1107 !FT->getParamType(2)->isIntegerTy() ||
1108 !FT->getParamType(3)->isPointerTy() ||
1109 !FT->getReturnType()->isIntegerTy())
1112 // Get the element size and count.
1113 ConstantInt *SizeC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
1114 ConstantInt *CountC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
1115 if (!SizeC || !CountC) return 0;
1116 uint64_t Bytes = SizeC->getZExtValue()*CountC->getZExtValue();
1118 // If this is writing zero records, remove the call (it's a noop).
1120 return ConstantInt::get(CI->getType(), 0);
1122 // If this is writing one byte, turn it into fputc.
1123 // This optimisation is only valid, if the return value is unused.
1124 if (Bytes == 1 && CI->use_empty()) { // fwrite(S,1,1,F) -> fputc(S[0],F)
1125 Value *Char = B.CreateLoad(CastToCStr(CI->getArgOperand(0), B), "char");
1126 Value *NewCI = EmitFPutC(Char, CI->getArgOperand(3), B, TD, TLI);
1127 return NewCI ? ConstantInt::get(CI->getType(), 1) : 0;
1134 //===---------------------------------------===//
1135 // 'fputs' Optimizations
1137 struct FPutsOpt : public LibCallOptimization {
1138 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1139 // These optimizations require DataLayout.
1142 // Require two pointers. Also, we can't optimize if return value is used.
1143 FunctionType *FT = Callee->getFunctionType();
1144 if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
1145 !FT->getParamType(1)->isPointerTy() ||
1149 // fputs(s,F) --> fwrite(s,1,strlen(s),F)
1150 uint64_t Len = GetStringLength(CI->getArgOperand(0));
1152 // Known to have no uses (see above).
1153 return EmitFWrite(CI->getArgOperand(0),
1154 ConstantInt::get(TD->getIntPtrType(*Context), Len-1),
1155 CI->getArgOperand(1), B, TD, TLI);
1159 //===---------------------------------------===//
1160 // 'fprintf' Optimizations
1162 struct FPrintFOpt : public LibCallOptimization {
1163 Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
1165 // All the optimizations depend on the format string.
1166 StringRef FormatStr;
1167 if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
1170 // fprintf(F, "foo") --> fwrite("foo", 3, 1, F)
1171 if (CI->getNumArgOperands() == 2) {
1172 for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
1173 if (FormatStr[i] == '%') // Could handle %% -> % if we cared.
1174 return 0; // We found a format specifier.
1176 // These optimizations require DataLayout.
1179 Value *NewCI = EmitFWrite(CI->getArgOperand(1),
1180 ConstantInt::get(TD->getIntPtrType(*Context),
1182 CI->getArgOperand(0), B, TD, TLI);
1183 return NewCI ? ConstantInt::get(CI->getType(), FormatStr.size()) : 0;
1186 // The remaining optimizations require the format string to be "%s" or "%c"
1187 // and have an extra operand.
1188 if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
1189 CI->getNumArgOperands() < 3)
1192 // Decode the second character of the format string.
1193 if (FormatStr[1] == 'c') {
1194 // fprintf(F, "%c", chr) --> fputc(chr, F)
1195 if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
1196 Value *NewCI = EmitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B,
1198 return NewCI ? ConstantInt::get(CI->getType(), 1) : 0;
1201 if (FormatStr[1] == 's') {
1202 // fprintf(F, "%s", str) --> fputs(str, F)
1203 if (!CI->getArgOperand(2)->getType()->isPointerTy() || !CI->use_empty())
1205 return EmitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TD, TLI);
1210 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1211 // Require two fixed paramters as pointers and integer result.
1212 FunctionType *FT = Callee->getFunctionType();
1213 if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
1214 !FT->getParamType(1)->isPointerTy() ||
1215 !FT->getReturnType()->isIntegerTy())
1218 if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
1222 // fprintf(stream, format, ...) -> fiprintf(stream, format, ...) if no
1223 // floating point arguments.
1224 if (TLI->has(LibFunc::fiprintf) && !CallHasFloatingPointArgument(CI)) {
1225 Module *M = B.GetInsertBlock()->getParent()->getParent();
1226 Constant *FIPrintFFn =
1227 M->getOrInsertFunction("fiprintf", FT, Callee->getAttributes());
1228 CallInst *New = cast<CallInst>(CI->clone());
1229 New->setCalledFunction(FIPrintFFn);
1237 //===---------------------------------------===//
1238 // 'puts' Optimizations
1240 struct PutsOpt : public LibCallOptimization {
1241 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1242 // Require one fixed pointer argument and an integer/void result.
1243 FunctionType *FT = Callee->getFunctionType();
1244 if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
1245 !(FT->getReturnType()->isIntegerTy() ||
1246 FT->getReturnType()->isVoidTy()))
1249 // Check for a constant string.
1251 if (!getConstantStringInfo(CI->getArgOperand(0), Str))
1254 if (Str.empty() && CI->use_empty()) {
1255 // puts("") -> putchar('\n')
1256 Value *Res = EmitPutChar(B.getInt32('\n'), B, TD, TLI);
1257 if (CI->use_empty() || !Res) return Res;
1258 return B.CreateIntCast(Res, CI->getType(), true);
1265 } // end anonymous namespace.
1267 //===----------------------------------------------------------------------===//
1268 // SimplifyLibCalls Pass Implementation
1269 //===----------------------------------------------------------------------===//
1272 /// This pass optimizes well known library functions from libc and libm.
1274 class SimplifyLibCalls : public FunctionPass {
1275 TargetLibraryInfo *TLI;
1277 StringMap<LibCallOptimization*> Optimizations;
1278 // String and Memory LibCall Optimizations
1279 StrCpyOpt StrCpy; StrCpyOpt StrCpyChk;
1280 StpCpyOpt StpCpy; StpCpyOpt StpCpyChk;
1282 StrLenOpt StrLen; StrPBrkOpt StrPBrk;
1283 StrToOpt StrTo; StrSpnOpt StrSpn; StrCSpnOpt StrCSpn; StrStrOpt StrStr;
1284 MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
1285 // Math Library Optimizations
1286 CosOpt Cos; PowOpt Pow; Exp2Opt Exp2;
1287 UnaryDoubleFPOpt UnaryDoubleFP, UnsafeUnaryDoubleFP;
1288 // Integer Optimizations
1289 FFSOpt FFS; AbsOpt Abs; IsDigitOpt IsDigit; IsAsciiOpt IsAscii;
1291 // Formatting and IO Optimizations
1292 SPrintFOpt SPrintF; PrintFOpt PrintF;
1293 FWriteOpt FWrite; FPutsOpt FPuts; FPrintFOpt FPrintF;
1296 bool Modified; // This is only used by doInitialization.
1298 static char ID; // Pass identification
1299 SimplifyLibCalls() : FunctionPass(ID), StrCpy(false), StrCpyChk(true),
1300 StpCpy(false), StpCpyChk(true),
1301 UnaryDoubleFP(false), UnsafeUnaryDoubleFP(true) {
1302 initializeSimplifyLibCallsPass(*PassRegistry::getPassRegistry());
1304 void AddOpt(LibFunc::Func F, LibCallOptimization* Opt);
1305 void AddOpt(LibFunc::Func F1, LibFunc::Func F2, LibCallOptimization* Opt);
1307 void InitOptimizations();
1308 bool runOnFunction(Function &F);
1310 void setDoesNotAccessMemory(Function &F);
1311 void setOnlyReadsMemory(Function &F);
1312 void setDoesNotThrow(Function &F);
1313 void setDoesNotCapture(Function &F, unsigned n);
1314 void setDoesNotAlias(Function &F, unsigned n);
1315 bool doInitialization(Module &M);
1317 void inferPrototypeAttributes(Function &F);
1318 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
1319 AU.addRequired<TargetLibraryInfo>();
1322 } // end anonymous namespace.
1324 char SimplifyLibCalls::ID = 0;
1326 INITIALIZE_PASS_BEGIN(SimplifyLibCalls, "simplify-libcalls",
1327 "Simplify well-known library calls", false, false)
1328 INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfo)
1329 INITIALIZE_PASS_END(SimplifyLibCalls, "simplify-libcalls",
1330 "Simplify well-known library calls", false, false)
1332 // Public interface to the Simplify LibCalls pass.
1333 FunctionPass *llvm::createSimplifyLibCallsPass() {
1334 return new SimplifyLibCalls();
1337 void SimplifyLibCalls::AddOpt(LibFunc::Func F, LibCallOptimization* Opt) {
1339 Optimizations[TLI->getName(F)] = Opt;
1342 void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2,
1343 LibCallOptimization* Opt) {
1344 if (TLI->has(F1) && TLI->has(F2))
1345 Optimizations[TLI->getName(F1)] = Opt;
1348 /// Optimizations - Populate the Optimizations map with all the optimizations
1350 void SimplifyLibCalls::InitOptimizations() {
1351 // String and Memory LibCall Optimizations
1352 Optimizations["strcpy"] = &StrCpy;
1353 Optimizations["strncpy"] = &StrNCpy;
1354 Optimizations["stpcpy"] = &StpCpy;
1355 Optimizations["strlen"] = &StrLen;
1356 Optimizations["strpbrk"] = &StrPBrk;
1357 Optimizations["strtol"] = &StrTo;
1358 Optimizations["strtod"] = &StrTo;
1359 Optimizations["strtof"] = &StrTo;
1360 Optimizations["strtoul"] = &StrTo;
1361 Optimizations["strtoll"] = &StrTo;
1362 Optimizations["strtold"] = &StrTo;
1363 Optimizations["strtoull"] = &StrTo;
1364 Optimizations["strspn"] = &StrSpn;
1365 Optimizations["strcspn"] = &StrCSpn;
1366 Optimizations["strstr"] = &StrStr;
1367 Optimizations["memcmp"] = &MemCmp;
1368 AddOpt(LibFunc::memcpy, &MemCpy);
1369 Optimizations["memmove"] = &MemMove;
1370 AddOpt(LibFunc::memset, &MemSet);
1372 // _chk variants of String and Memory LibCall Optimizations.
1373 Optimizations["__strcpy_chk"] = &StrCpyChk;
1374 Optimizations["__stpcpy_chk"] = &StpCpyChk;
1376 // Math Library Optimizations
1377 Optimizations["cosf"] = &Cos;
1378 Optimizations["cos"] = &Cos;
1379 Optimizations["cosl"] = &Cos;
1380 Optimizations["powf"] = &Pow;
1381 Optimizations["pow"] = &Pow;
1382 Optimizations["powl"] = &Pow;
1383 Optimizations["llvm.pow.f32"] = &Pow;
1384 Optimizations["llvm.pow.f64"] = &Pow;
1385 Optimizations["llvm.pow.f80"] = &Pow;
1386 Optimizations["llvm.pow.f128"] = &Pow;
1387 Optimizations["llvm.pow.ppcf128"] = &Pow;
1388 Optimizations["exp2l"] = &Exp2;
1389 Optimizations["exp2"] = &Exp2;
1390 Optimizations["exp2f"] = &Exp2;
1391 Optimizations["llvm.exp2.ppcf128"] = &Exp2;
1392 Optimizations["llvm.exp2.f128"] = &Exp2;
1393 Optimizations["llvm.exp2.f80"] = &Exp2;
1394 Optimizations["llvm.exp2.f64"] = &Exp2;
1395 Optimizations["llvm.exp2.f32"] = &Exp2;
1397 AddOpt(LibFunc::ceil, LibFunc::ceilf, &UnaryDoubleFP);
1398 AddOpt(LibFunc::fabs, LibFunc::fabsf, &UnaryDoubleFP);
1399 AddOpt(LibFunc::floor, LibFunc::floorf, &UnaryDoubleFP);
1400 AddOpt(LibFunc::rint, LibFunc::rintf, &UnaryDoubleFP);
1401 AddOpt(LibFunc::round, LibFunc::roundf, &UnaryDoubleFP);
1402 AddOpt(LibFunc::nearbyint, LibFunc::nearbyintf, &UnaryDoubleFP);
1403 AddOpt(LibFunc::trunc, LibFunc::truncf, &UnaryDoubleFP);
1405 if(UnsafeFPShrink) {
1406 AddOpt(LibFunc::acos, LibFunc::acosf, &UnsafeUnaryDoubleFP);
1407 AddOpt(LibFunc::acosh, LibFunc::acoshf, &UnsafeUnaryDoubleFP);
1408 AddOpt(LibFunc::asin, LibFunc::asinf, &UnsafeUnaryDoubleFP);
1409 AddOpt(LibFunc::asinh, LibFunc::asinhf, &UnsafeUnaryDoubleFP);
1410 AddOpt(LibFunc::atan, LibFunc::atanf, &UnsafeUnaryDoubleFP);
1411 AddOpt(LibFunc::atanh, LibFunc::atanhf, &UnsafeUnaryDoubleFP);
1412 AddOpt(LibFunc::cbrt, LibFunc::cbrtf, &UnsafeUnaryDoubleFP);
1413 AddOpt(LibFunc::cosh, LibFunc::coshf, &UnsafeUnaryDoubleFP);
1414 AddOpt(LibFunc::exp, LibFunc::expf, &UnsafeUnaryDoubleFP);
1415 AddOpt(LibFunc::exp10, LibFunc::exp10f, &UnsafeUnaryDoubleFP);
1416 AddOpt(LibFunc::expm1, LibFunc::expm1f, &UnsafeUnaryDoubleFP);
1417 AddOpt(LibFunc::log, LibFunc::logf, &UnsafeUnaryDoubleFP);
1418 AddOpt(LibFunc::log10, LibFunc::log10f, &UnsafeUnaryDoubleFP);
1419 AddOpt(LibFunc::log1p, LibFunc::log1pf, &UnsafeUnaryDoubleFP);
1420 AddOpt(LibFunc::log2, LibFunc::log2f, &UnsafeUnaryDoubleFP);
1421 AddOpt(LibFunc::logb, LibFunc::logbf, &UnsafeUnaryDoubleFP);
1422 AddOpt(LibFunc::sin, LibFunc::sinf, &UnsafeUnaryDoubleFP);
1423 AddOpt(LibFunc::sinh, LibFunc::sinhf, &UnsafeUnaryDoubleFP);
1424 AddOpt(LibFunc::sqrt, LibFunc::sqrtf, &UnsafeUnaryDoubleFP);
1425 AddOpt(LibFunc::tan, LibFunc::tanf, &UnsafeUnaryDoubleFP);
1426 AddOpt(LibFunc::tanh, LibFunc::tanhf, &UnsafeUnaryDoubleFP);
1429 // Integer Optimizations
1430 Optimizations["ffs"] = &FFS;
1431 Optimizations["ffsl"] = &FFS;
1432 Optimizations["ffsll"] = &FFS;
1433 Optimizations["abs"] = &Abs;
1434 Optimizations["labs"] = &Abs;
1435 Optimizations["llabs"] = &Abs;
1436 Optimizations["isdigit"] = &IsDigit;
1437 Optimizations["isascii"] = &IsAscii;
1438 Optimizations["toascii"] = &ToAscii;
1440 // Formatting and IO Optimizations
1441 Optimizations["sprintf"] = &SPrintF;
1442 Optimizations["printf"] = &PrintF;
1443 AddOpt(LibFunc::fwrite, &FWrite);
1444 AddOpt(LibFunc::fputs, &FPuts);
1445 Optimizations["fprintf"] = &FPrintF;
1446 Optimizations["puts"] = &Puts;
1450 /// runOnFunction - Top level algorithm.
1452 bool SimplifyLibCalls::runOnFunction(Function &F) {
1453 TLI = &getAnalysis<TargetLibraryInfo>();
1455 if (Optimizations.empty())
1456 InitOptimizations();
1458 const DataLayout *TD = getAnalysisIfAvailable<DataLayout>();
1460 IRBuilder<> Builder(F.getContext());
1462 bool Changed = false;
1463 for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
1464 for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ) {
1465 // Ignore non-calls.
1466 CallInst *CI = dyn_cast<CallInst>(I++);
1469 // Ignore indirect calls and calls to non-external functions.
1470 Function *Callee = CI->getCalledFunction();
1471 if (Callee == 0 || !Callee->isDeclaration() ||
1472 !(Callee->hasExternalLinkage() || Callee->hasDLLImportLinkage()))
1475 // Ignore unknown calls.
1476 LibCallOptimization *LCO = Optimizations.lookup(Callee->getName());
1479 // Set the builder to the instruction after the call.
1480 Builder.SetInsertPoint(BB, I);
1482 // Use debug location of CI for all new instructions.
1483 Builder.SetCurrentDebugLocation(CI->getDebugLoc());
1485 // Try to optimize this call.
1486 Value *Result = LCO->OptimizeCall(CI, TD, TLI, Builder);
1487 if (Result == 0) continue;
1489 DEBUG(dbgs() << "SimplifyLibCalls simplified: " << *CI;
1490 dbgs() << " into: " << *Result << "\n");
1492 // Something changed!
1496 // Inspect the instruction after the call (which was potentially just
1500 if (CI != Result && !CI->use_empty()) {
1501 CI->replaceAllUsesWith(Result);
1502 if (!Result->hasName())
1503 Result->takeName(CI);
1505 CI->eraseFromParent();
1511 // Utility methods for doInitialization.
1513 void SimplifyLibCalls::setDoesNotAccessMemory(Function &F) {
1514 if (!F.doesNotAccessMemory()) {
1515 F.setDoesNotAccessMemory();
1520 void SimplifyLibCalls::setOnlyReadsMemory(Function &F) {
1521 if (!F.onlyReadsMemory()) {
1522 F.setOnlyReadsMemory();
1527 void SimplifyLibCalls::setDoesNotThrow(Function &F) {
1528 if (!F.doesNotThrow()) {
1529 F.setDoesNotThrow();
1534 void SimplifyLibCalls::setDoesNotCapture(Function &F, unsigned n) {
1535 if (!F.doesNotCapture(n)) {
1536 F.setDoesNotCapture(n);
1541 void SimplifyLibCalls::setDoesNotAlias(Function &F, unsigned n) {
1542 if (!F.doesNotAlias(n)) {
1543 F.setDoesNotAlias(n);
1550 void SimplifyLibCalls::inferPrototypeAttributes(Function &F) {
1551 FunctionType *FTy = F.getFunctionType();
1553 StringRef Name = F.getName();
1556 if (Name == "strlen") {
1557 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1559 setOnlyReadsMemory(F);
1561 setDoesNotCapture(F, 1);
1562 } else if (Name == "strchr" ||
1563 Name == "strrchr") {
1564 if (FTy->getNumParams() != 2 ||
1565 !FTy->getParamType(0)->isPointerTy() ||
1566 !FTy->getParamType(1)->isIntegerTy())
1568 setOnlyReadsMemory(F);
1570 } else if (Name == "strcpy" ||
1576 Name == "strtoul" ||
1577 Name == "strtoll" ||
1578 Name == "strtold" ||
1579 Name == "strncat" ||
1580 Name == "strncpy" ||
1581 Name == "stpncpy" ||
1582 Name == "strtoull") {
1583 if (FTy->getNumParams() < 2 ||
1584 !FTy->getParamType(1)->isPointerTy())
1587 setDoesNotCapture(F, 2);
1588 } else if (Name == "strxfrm") {
1589 if (FTy->getNumParams() != 3 ||
1590 !FTy->getParamType(0)->isPointerTy() ||
1591 !FTy->getParamType(1)->isPointerTy())
1594 setDoesNotCapture(F, 1);
1595 setDoesNotCapture(F, 2);
1596 } else if (Name == "strcmp" ||
1598 Name == "strncmp" ||
1599 Name == "strcspn" ||
1600 Name == "strcoll" ||
1601 Name == "strcasecmp" ||
1602 Name == "strncasecmp") {
1603 if (FTy->getNumParams() < 2 ||
1604 !FTy->getParamType(0)->isPointerTy() ||
1605 !FTy->getParamType(1)->isPointerTy())
1607 setOnlyReadsMemory(F);
1609 setDoesNotCapture(F, 1);
1610 setDoesNotCapture(F, 2);
1611 } else if (Name == "strstr" ||
1612 Name == "strpbrk") {
1613 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1615 setOnlyReadsMemory(F);
1617 setDoesNotCapture(F, 2);
1618 } else if (Name == "strtok" ||
1619 Name == "strtok_r") {
1620 if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy())
1623 setDoesNotCapture(F, 2);
1624 } else if (Name == "scanf" ||
1626 Name == "setvbuf") {
1627 if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy())
1630 setDoesNotCapture(F, 1);
1631 } else if (Name == "strdup" ||
1632 Name == "strndup") {
1633 if (FTy->getNumParams() < 1 || !FTy->getReturnType()->isPointerTy() ||
1634 !FTy->getParamType(0)->isPointerTy())
1637 setDoesNotAlias(F, 0);
1638 setDoesNotCapture(F, 1);
1639 } else if (Name == "stat" ||
1641 Name == "sprintf" ||
1642 Name == "statvfs") {
1643 if (FTy->getNumParams() < 2 ||
1644 !FTy->getParamType(0)->isPointerTy() ||
1645 !FTy->getParamType(1)->isPointerTy())
1648 setDoesNotCapture(F, 1);
1649 setDoesNotCapture(F, 2);
1650 } else if (Name == "snprintf") {
1651 if (FTy->getNumParams() != 3 ||
1652 !FTy->getParamType(0)->isPointerTy() ||
1653 !FTy->getParamType(2)->isPointerTy())
1656 setDoesNotCapture(F, 1);
1657 setDoesNotCapture(F, 3);
1658 } else if (Name == "setitimer") {
1659 if (FTy->getNumParams() != 3 ||
1660 !FTy->getParamType(1)->isPointerTy() ||
1661 !FTy->getParamType(2)->isPointerTy())
1664 setDoesNotCapture(F, 2);
1665 setDoesNotCapture(F, 3);
1666 } else if (Name == "system") {
1667 if (FTy->getNumParams() != 1 ||
1668 !FTy->getParamType(0)->isPointerTy())
1670 // May throw; "system" is a valid pthread cancellation point.
1671 setDoesNotCapture(F, 1);
1675 if (Name == "malloc") {
1676 if (FTy->getNumParams() != 1 ||
1677 !FTy->getReturnType()->isPointerTy())
1680 setDoesNotAlias(F, 0);
1681 } else if (Name == "memcmp") {
1682 if (FTy->getNumParams() != 3 ||
1683 !FTy->getParamType(0)->isPointerTy() ||
1684 !FTy->getParamType(1)->isPointerTy())
1686 setOnlyReadsMemory(F);
1688 setDoesNotCapture(F, 1);
1689 setDoesNotCapture(F, 2);
1690 } else if (Name == "memchr" ||
1691 Name == "memrchr") {
1692 if (FTy->getNumParams() != 3)
1694 setOnlyReadsMemory(F);
1696 } else if (Name == "modf" ||
1700 Name == "memccpy" ||
1701 Name == "memmove") {
1702 if (FTy->getNumParams() < 2 ||
1703 !FTy->getParamType(1)->isPointerTy())
1706 setDoesNotCapture(F, 2);
1707 } else if (Name == "memalign") {
1708 if (!FTy->getReturnType()->isPointerTy())
1710 setDoesNotAlias(F, 0);
1711 } else if (Name == "mkdir" ||
1713 if (FTy->getNumParams() == 0 ||
1714 !FTy->getParamType(0)->isPointerTy())
1717 setDoesNotCapture(F, 1);
1721 if (Name == "realloc") {
1722 if (FTy->getNumParams() != 2 ||
1723 !FTy->getParamType(0)->isPointerTy() ||
1724 !FTy->getReturnType()->isPointerTy())
1727 setDoesNotAlias(F, 0);
1728 setDoesNotCapture(F, 1);
1729 } else if (Name == "read") {
1730 if (FTy->getNumParams() != 3 ||
1731 !FTy->getParamType(1)->isPointerTy())
1733 // May throw; "read" is a valid pthread cancellation point.
1734 setDoesNotCapture(F, 2);
1735 } else if (Name == "rmdir" ||
1738 Name == "realpath") {
1739 if (FTy->getNumParams() < 1 ||
1740 !FTy->getParamType(0)->isPointerTy())
1743 setDoesNotCapture(F, 1);
1744 } else if (Name == "rename" ||
1745 Name == "readlink") {
1746 if (FTy->getNumParams() < 2 ||
1747 !FTy->getParamType(0)->isPointerTy() ||
1748 !FTy->getParamType(1)->isPointerTy())
1751 setDoesNotCapture(F, 1);
1752 setDoesNotCapture(F, 2);
1756 if (Name == "write") {
1757 if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy())
1759 // May throw; "write" is a valid pthread cancellation point.
1760 setDoesNotCapture(F, 2);
1764 if (Name == "bcopy") {
1765 if (FTy->getNumParams() != 3 ||
1766 !FTy->getParamType(0)->isPointerTy() ||
1767 !FTy->getParamType(1)->isPointerTy())
1770 setDoesNotCapture(F, 1);
1771 setDoesNotCapture(F, 2);
1772 } else if (Name == "bcmp") {
1773 if (FTy->getNumParams() != 3 ||
1774 !FTy->getParamType(0)->isPointerTy() ||
1775 !FTy->getParamType(1)->isPointerTy())
1778 setOnlyReadsMemory(F);
1779 setDoesNotCapture(F, 1);
1780 setDoesNotCapture(F, 2);
1781 } else if (Name == "bzero") {
1782 if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
1785 setDoesNotCapture(F, 1);
1789 if (Name == "calloc") {
1790 if (FTy->getNumParams() != 2 ||
1791 !FTy->getReturnType()->isPointerTy())
1794 setDoesNotAlias(F, 0);
1795 } else if (Name == "chmod" ||
1797 Name == "ctermid" ||
1798 Name == "clearerr" ||
1799 Name == "closedir") {
1800 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
1803 setDoesNotCapture(F, 1);
1807 if (Name == "atoi" ||
1811 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1814 setOnlyReadsMemory(F);
1815 setDoesNotCapture(F, 1);
1816 } else if (Name == "access") {
1817 if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
1820 setDoesNotCapture(F, 1);
1824 if (Name == "fopen") {
1825 if (FTy->getNumParams() != 2 ||
1826 !FTy->getReturnType()->isPointerTy() ||
1827 !FTy->getParamType(0)->isPointerTy() ||
1828 !FTy->getParamType(1)->isPointerTy())
1831 setDoesNotAlias(F, 0);
1832 setDoesNotCapture(F, 1);
1833 setDoesNotCapture(F, 2);
1834 } else if (Name == "fdopen") {
1835 if (FTy->getNumParams() != 2 ||
1836 !FTy->getReturnType()->isPointerTy() ||
1837 !FTy->getParamType(1)->isPointerTy())
1840 setDoesNotAlias(F, 0);
1841 setDoesNotCapture(F, 2);
1842 } else if (Name == "feof" ||
1852 Name == "fsetpos" ||
1853 Name == "flockfile" ||
1854 Name == "funlockfile" ||
1855 Name == "ftrylockfile") {
1856 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
1859 setDoesNotCapture(F, 1);
1860 } else if (Name == "ferror") {
1861 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1864 setDoesNotCapture(F, 1);
1865 setOnlyReadsMemory(F);
1866 } else if (Name == "fputc" ||
1871 Name == "fstatvfs") {
1872 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1875 setDoesNotCapture(F, 2);
1876 } else if (Name == "fgets") {
1877 if (FTy->getNumParams() != 3 ||
1878 !FTy->getParamType(0)->isPointerTy() ||
1879 !FTy->getParamType(2)->isPointerTy())
1882 setDoesNotCapture(F, 3);
1883 } else if (Name == "fread" ||
1885 if (FTy->getNumParams() != 4 ||
1886 !FTy->getParamType(0)->isPointerTy() ||
1887 !FTy->getParamType(3)->isPointerTy())
1890 setDoesNotCapture(F, 1);
1891 setDoesNotCapture(F, 4);
1892 } else if (Name == "fputs" ||
1894 Name == "fprintf" ||
1895 Name == "fgetpos") {
1896 if (FTy->getNumParams() < 2 ||
1897 !FTy->getParamType(0)->isPointerTy() ||
1898 !FTy->getParamType(1)->isPointerTy())
1901 setDoesNotCapture(F, 1);
1902 setDoesNotCapture(F, 2);
1906 if (Name == "getc" ||
1907 Name == "getlogin_r" ||
1908 Name == "getc_unlocked") {
1909 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
1912 setDoesNotCapture(F, 1);
1913 } else if (Name == "getenv") {
1914 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1917 setOnlyReadsMemory(F);
1918 setDoesNotCapture(F, 1);
1919 } else if (Name == "gets" ||
1920 Name == "getchar") {
1922 } else if (Name == "getitimer") {
1923 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1926 setDoesNotCapture(F, 2);
1927 } else if (Name == "getpwnam") {
1928 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1931 setDoesNotCapture(F, 1);
1935 if (Name == "ungetc") {
1936 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1939 setDoesNotCapture(F, 2);
1940 } else if (Name == "uname" ||
1942 Name == "unsetenv") {
1943 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1946 setDoesNotCapture(F, 1);
1947 } else if (Name == "utime" ||
1949 if (FTy->getNumParams() != 2 ||
1950 !FTy->getParamType(0)->isPointerTy() ||
1951 !FTy->getParamType(1)->isPointerTy())
1954 setDoesNotCapture(F, 1);
1955 setDoesNotCapture(F, 2);
1959 if (Name == "putc") {
1960 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1963 setDoesNotCapture(F, 2);
1964 } else if (Name == "puts" ||
1967 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1970 setDoesNotCapture(F, 1);
1971 } else if (Name == "pread" ||
1973 if (FTy->getNumParams() != 4 || !FTy->getParamType(1)->isPointerTy())
1975 // May throw; these are valid pthread cancellation points.
1976 setDoesNotCapture(F, 2);
1977 } else if (Name == "putchar") {
1979 } else if (Name == "popen") {
1980 if (FTy->getNumParams() != 2 ||
1981 !FTy->getReturnType()->isPointerTy() ||
1982 !FTy->getParamType(0)->isPointerTy() ||
1983 !FTy->getParamType(1)->isPointerTy())
1986 setDoesNotAlias(F, 0);
1987 setDoesNotCapture(F, 1);
1988 setDoesNotCapture(F, 2);
1989 } else if (Name == "pclose") {
1990 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1993 setDoesNotCapture(F, 1);
1997 if (Name == "vscanf") {
1998 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2001 setDoesNotCapture(F, 1);
2002 } else if (Name == "vsscanf" ||
2003 Name == "vfscanf") {
2004 if (FTy->getNumParams() != 3 ||
2005 !FTy->getParamType(1)->isPointerTy() ||
2006 !FTy->getParamType(2)->isPointerTy())
2009 setDoesNotCapture(F, 1);
2010 setDoesNotCapture(F, 2);
2011 } else if (Name == "valloc") {
2012 if (!FTy->getReturnType()->isPointerTy())
2015 setDoesNotAlias(F, 0);
2016 } else if (Name == "vprintf") {
2017 if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
2020 setDoesNotCapture(F, 1);
2021 } else if (Name == "vfprintf" ||
2022 Name == "vsprintf") {
2023 if (FTy->getNumParams() != 3 ||
2024 !FTy->getParamType(0)->isPointerTy() ||
2025 !FTy->getParamType(1)->isPointerTy())
2028 setDoesNotCapture(F, 1);
2029 setDoesNotCapture(F, 2);
2030 } else if (Name == "vsnprintf") {
2031 if (FTy->getNumParams() != 4 ||
2032 !FTy->getParamType(0)->isPointerTy() ||
2033 !FTy->getParamType(2)->isPointerTy())
2036 setDoesNotCapture(F, 1);
2037 setDoesNotCapture(F, 3);
2041 if (Name == "open") {
2042 if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
2044 // May throw; "open" is a valid pthread cancellation point.
2045 setDoesNotCapture(F, 1);
2046 } else if (Name == "opendir") {
2047 if (FTy->getNumParams() != 1 ||
2048 !FTy->getReturnType()->isPointerTy() ||
2049 !FTy->getParamType(0)->isPointerTy())
2052 setDoesNotAlias(F, 0);
2053 setDoesNotCapture(F, 1);
2057 if (Name == "tmpfile") {
2058 if (!FTy->getReturnType()->isPointerTy())
2061 setDoesNotAlias(F, 0);
2062 } else if (Name == "times") {
2063 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2066 setDoesNotCapture(F, 1);
2070 if (Name == "htonl" ||
2073 setDoesNotAccessMemory(F);
2077 if (Name == "ntohl" ||
2080 setDoesNotAccessMemory(F);
2084 if (Name == "lstat") {
2085 if (FTy->getNumParams() != 2 ||
2086 !FTy->getParamType(0)->isPointerTy() ||
2087 !FTy->getParamType(1)->isPointerTy())
2090 setDoesNotCapture(F, 1);
2091 setDoesNotCapture(F, 2);
2092 } else if (Name == "lchown") {
2093 if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy())
2096 setDoesNotCapture(F, 1);
2100 if (Name == "qsort") {
2101 if (FTy->getNumParams() != 4 || !FTy->getParamType(3)->isPointerTy())
2103 // May throw; places call through function pointer.
2104 setDoesNotCapture(F, 4);
2108 if (Name == "__strdup" ||
2109 Name == "__strndup") {
2110 if (FTy->getNumParams() < 1 ||
2111 !FTy->getReturnType()->isPointerTy() ||
2112 !FTy->getParamType(0)->isPointerTy())
2115 setDoesNotAlias(F, 0);
2116 setDoesNotCapture(F, 1);
2117 } else if (Name == "__strtok_r") {
2118 if (FTy->getNumParams() != 3 ||
2119 !FTy->getParamType(1)->isPointerTy())
2122 setDoesNotCapture(F, 2);
2123 } else if (Name == "_IO_getc") {
2124 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2127 setDoesNotCapture(F, 1);
2128 } else if (Name == "_IO_putc") {
2129 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2132 setDoesNotCapture(F, 2);
2136 if (Name == "\1__isoc99_scanf") {
2137 if (FTy->getNumParams() < 1 ||
2138 !FTy->getParamType(0)->isPointerTy())
2141 setDoesNotCapture(F, 1);
2142 } else if (Name == "\1stat64" ||
2143 Name == "\1lstat64" ||
2144 Name == "\1statvfs64" ||
2145 Name == "\1__isoc99_sscanf") {
2146 if (FTy->getNumParams() < 1 ||
2147 !FTy->getParamType(0)->isPointerTy() ||
2148 !FTy->getParamType(1)->isPointerTy())
2151 setDoesNotCapture(F, 1);
2152 setDoesNotCapture(F, 2);
2153 } else if (Name == "\1fopen64") {
2154 if (FTy->getNumParams() != 2 ||
2155 !FTy->getReturnType()->isPointerTy() ||
2156 !FTy->getParamType(0)->isPointerTy() ||
2157 !FTy->getParamType(1)->isPointerTy())
2160 setDoesNotAlias(F, 0);
2161 setDoesNotCapture(F, 1);
2162 setDoesNotCapture(F, 2);
2163 } else if (Name == "\1fseeko64" ||
2164 Name == "\1ftello64") {
2165 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
2168 setDoesNotCapture(F, 1);
2169 } else if (Name == "\1tmpfile64") {
2170 if (!FTy->getReturnType()->isPointerTy())
2173 setDoesNotAlias(F, 0);
2174 } else if (Name == "\1fstat64" ||
2175 Name == "\1fstatvfs64") {
2176 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2179 setDoesNotCapture(F, 2);
2180 } else if (Name == "\1open64") {
2181 if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
2183 // May throw; "open" is a valid pthread cancellation point.
2184 setDoesNotCapture(F, 1);
2190 /// doInitialization - Add attributes to well-known functions.
2192 bool SimplifyLibCalls::doInitialization(Module &M) {
2194 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
2196 if (F.isDeclaration() && F.hasName())
2197 inferPrototypeAttributes(F);
2203 // Additional cases that we need to add to this file:
2206 // * cbrt(expN(X)) -> expN(x/3)
2207 // * cbrt(sqrt(x)) -> pow(x,1/6)
2208 // * cbrt(sqrt(x)) -> pow(x,1/9)
2211 // * exp(log(x)) -> x
2214 // * log(exp(x)) -> x
2215 // * log(x**y) -> y*log(x)
2216 // * log(exp(y)) -> y*log(e)
2217 // * log(exp2(y)) -> y*log(2)
2218 // * log(exp10(y)) -> y*log(10)
2219 // * log(sqrt(x)) -> 0.5*log(x)
2220 // * log(pow(x,y)) -> y*log(x)
2222 // lround, lroundf, lroundl:
2223 // * lround(cnst) -> cnst'
2226 // * pow(exp(x),y) -> exp(x*y)
2227 // * pow(sqrt(x),y) -> pow(x,y*0.5)
2228 // * pow(pow(x,y),z)-> pow(x,y*z)
2230 // round, roundf, roundl:
2231 // * round(cnst) -> cnst'
2234 // * signbit(cnst) -> cnst'
2235 // * signbit(nncst) -> 0 (if pstv is a non-negative constant)
2237 // sqrt, sqrtf, sqrtl:
2238 // * sqrt(expN(x)) -> expN(x*0.5)
2239 // * sqrt(Nroot(x)) -> pow(x,1/(2*N))
2240 // * sqrt(pow(x,y)) -> pow(|x|,y*0.5)
2243 // * strchr(p, 0) -> strlen(p)
2245 // * tan(atan(x)) -> x
2247 // trunc, truncf, truncl:
2248 // * trunc(cnst) -> cnst'