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 // 'strcmp' Optimizations
140 struct StrCmpOpt : public LibCallOptimization {
141 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
142 // Verify the "strcmp" function prototype.
143 FunctionType *FT = Callee->getFunctionType();
144 if (FT->getNumParams() != 2 ||
145 !FT->getReturnType()->isIntegerTy(32) ||
146 FT->getParamType(0) != FT->getParamType(1) ||
147 FT->getParamType(0) != B.getInt8PtrTy())
150 Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
151 if (Str1P == Str2P) // strcmp(x,x) -> 0
152 return ConstantInt::get(CI->getType(), 0);
154 StringRef Str1, Str2;
155 bool HasStr1 = getConstantStringInfo(Str1P, Str1);
156 bool HasStr2 = getConstantStringInfo(Str2P, Str2);
158 // strcmp(x, y) -> cnst (if both x and y are constant strings)
159 if (HasStr1 && HasStr2)
160 return ConstantInt::get(CI->getType(), Str1.compare(Str2));
162 if (HasStr1 && Str1.empty()) // strcmp("", x) -> -*x
163 return B.CreateNeg(B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"),
166 if (HasStr2 && Str2.empty()) // strcmp(x,"") -> *x
167 return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
169 // strcmp(P, "x") -> memcmp(P, "x", 2)
170 uint64_t Len1 = GetStringLength(Str1P);
171 uint64_t Len2 = GetStringLength(Str2P);
173 // These optimizations require DataLayout.
176 return EmitMemCmp(Str1P, Str2P,
177 ConstantInt::get(TD->getIntPtrType(*Context),
178 std::min(Len1, Len2)), B, TD, TLI);
185 //===---------------------------------------===//
186 // 'strncmp' Optimizations
188 struct StrNCmpOpt : public LibCallOptimization {
189 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
190 // Verify the "strncmp" function prototype.
191 FunctionType *FT = Callee->getFunctionType();
192 if (FT->getNumParams() != 3 ||
193 !FT->getReturnType()->isIntegerTy(32) ||
194 FT->getParamType(0) != FT->getParamType(1) ||
195 FT->getParamType(0) != B.getInt8PtrTy() ||
196 !FT->getParamType(2)->isIntegerTy())
199 Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
200 if (Str1P == Str2P) // strncmp(x,x,n) -> 0
201 return ConstantInt::get(CI->getType(), 0);
203 // Get the length argument if it is constant.
205 if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
206 Length = LengthArg->getZExtValue();
210 if (Length == 0) // strncmp(x,y,0) -> 0
211 return ConstantInt::get(CI->getType(), 0);
213 if (TD && Length == 1) // strncmp(x,y,1) -> memcmp(x,y,1)
214 return EmitMemCmp(Str1P, Str2P, CI->getArgOperand(2), B, TD, TLI);
216 StringRef Str1, Str2;
217 bool HasStr1 = getConstantStringInfo(Str1P, Str1);
218 bool HasStr2 = getConstantStringInfo(Str2P, Str2);
220 // strncmp(x, y) -> cnst (if both x and y are constant strings)
221 if (HasStr1 && HasStr2) {
222 StringRef SubStr1 = Str1.substr(0, Length);
223 StringRef SubStr2 = Str2.substr(0, Length);
224 return ConstantInt::get(CI->getType(), SubStr1.compare(SubStr2));
227 if (HasStr1 && Str1.empty()) // strncmp("", x, n) -> -*x
228 return B.CreateNeg(B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"),
231 if (HasStr2 && Str2.empty()) // strncmp(x, "", n) -> *x
232 return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
239 //===---------------------------------------===//
240 // 'strcpy' Optimizations
242 struct StrCpyOpt : public LibCallOptimization {
243 bool OptChkCall; // True if it's optimizing a __strcpy_chk libcall.
245 StrCpyOpt(bool c) : OptChkCall(c) {}
247 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
248 // Verify the "strcpy" function prototype.
249 unsigned NumParams = OptChkCall ? 3 : 2;
250 FunctionType *FT = Callee->getFunctionType();
251 if (FT->getNumParams() != NumParams ||
252 FT->getReturnType() != FT->getParamType(0) ||
253 FT->getParamType(0) != FT->getParamType(1) ||
254 FT->getParamType(0) != B.getInt8PtrTy())
257 Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
258 if (Dst == Src) // strcpy(x,x) -> x
261 // These optimizations require DataLayout.
264 // See if we can get the length of the input string.
265 uint64_t Len = GetStringLength(Src);
266 if (Len == 0) return 0;
268 // We have enough information to now generate the memcpy call to do the
269 // concatenation for us. Make a memcpy to copy the nul byte with align = 1.
271 !EmitMemCpyChk(Dst, Src,
272 ConstantInt::get(TD->getIntPtrType(*Context), Len),
273 CI->getArgOperand(2), B, TD, TLI))
274 B.CreateMemCpy(Dst, Src,
275 ConstantInt::get(TD->getIntPtrType(*Context), Len), 1);
280 //===---------------------------------------===//
281 // 'stpcpy' Optimizations
283 struct StpCpyOpt: public LibCallOptimization {
284 bool OptChkCall; // True if it's optimizing a __stpcpy_chk libcall.
286 StpCpyOpt(bool c) : OptChkCall(c) {}
288 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
289 // Verify the "stpcpy" function prototype.
290 unsigned NumParams = OptChkCall ? 3 : 2;
291 FunctionType *FT = Callee->getFunctionType();
292 if (FT->getNumParams() != NumParams ||
293 FT->getReturnType() != FT->getParamType(0) ||
294 FT->getParamType(0) != FT->getParamType(1) ||
295 FT->getParamType(0) != B.getInt8PtrTy())
298 // These optimizations require DataLayout.
301 Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
302 if (Dst == Src) { // stpcpy(x,x) -> x+strlen(x)
303 Value *StrLen = EmitStrLen(Src, B, TD, TLI);
304 return StrLen ? B.CreateInBoundsGEP(Dst, StrLen) : 0;
307 // See if we can get the length of the input string.
308 uint64_t Len = GetStringLength(Src);
309 if (Len == 0) return 0;
311 Value *LenV = ConstantInt::get(TD->getIntPtrType(*Context), Len);
312 Value *DstEnd = B.CreateGEP(Dst,
313 ConstantInt::get(TD->getIntPtrType(*Context),
316 // We have enough information to now generate the memcpy call to do the
317 // copy for us. Make a memcpy to copy the nul byte with align = 1.
318 if (!OptChkCall || !EmitMemCpyChk(Dst, Src, LenV, CI->getArgOperand(2), B,
320 B.CreateMemCpy(Dst, Src, LenV, 1);
325 //===---------------------------------------===//
326 // 'strncpy' Optimizations
328 struct StrNCpyOpt : public LibCallOptimization {
329 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
330 FunctionType *FT = Callee->getFunctionType();
331 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
332 FT->getParamType(0) != FT->getParamType(1) ||
333 FT->getParamType(0) != B.getInt8PtrTy() ||
334 !FT->getParamType(2)->isIntegerTy())
337 Value *Dst = CI->getArgOperand(0);
338 Value *Src = CI->getArgOperand(1);
339 Value *LenOp = CI->getArgOperand(2);
341 // See if we can get the length of the input string.
342 uint64_t SrcLen = GetStringLength(Src);
343 if (SrcLen == 0) return 0;
347 // strncpy(x, "", y) -> memset(x, '\0', y, 1)
348 B.CreateMemSet(Dst, B.getInt8('\0'), LenOp, 1);
353 if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(LenOp))
354 Len = LengthArg->getZExtValue();
358 if (Len == 0) return Dst; // strncpy(x, y, 0) -> x
360 // These optimizations require DataLayout.
363 // Let strncpy handle the zero padding
364 if (Len > SrcLen+1) return 0;
366 // strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant]
367 B.CreateMemCpy(Dst, Src,
368 ConstantInt::get(TD->getIntPtrType(*Context), Len), 1);
374 //===---------------------------------------===//
375 // 'strlen' Optimizations
377 struct StrLenOpt : public LibCallOptimization {
378 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
379 FunctionType *FT = Callee->getFunctionType();
380 if (FT->getNumParams() != 1 ||
381 FT->getParamType(0) != B.getInt8PtrTy() ||
382 !FT->getReturnType()->isIntegerTy())
385 Value *Src = CI->getArgOperand(0);
387 // Constant folding: strlen("xyz") -> 3
388 if (uint64_t Len = GetStringLength(Src))
389 return ConstantInt::get(CI->getType(), Len-1);
391 // strlen(x) != 0 --> *x != 0
392 // strlen(x) == 0 --> *x == 0
393 if (IsOnlyUsedInZeroEqualityComparison(CI))
394 return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
400 //===---------------------------------------===//
401 // 'strpbrk' Optimizations
403 struct StrPBrkOpt : public LibCallOptimization {
404 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
405 FunctionType *FT = Callee->getFunctionType();
406 if (FT->getNumParams() != 2 ||
407 FT->getParamType(0) != B.getInt8PtrTy() ||
408 FT->getParamType(1) != FT->getParamType(0) ||
409 FT->getReturnType() != FT->getParamType(0))
413 bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
414 bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
416 // strpbrk(s, "") -> NULL
417 // strpbrk("", s) -> NULL
418 if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
419 return Constant::getNullValue(CI->getType());
422 if (HasS1 && HasS2) {
423 size_t I = S1.find_first_of(S2);
424 if (I == std::string::npos) // No match.
425 return Constant::getNullValue(CI->getType());
427 return B.CreateGEP(CI->getArgOperand(0), B.getInt64(I), "strpbrk");
430 // strpbrk(s, "a") -> strchr(s, 'a')
431 if (TD && HasS2 && S2.size() == 1)
432 return EmitStrChr(CI->getArgOperand(0), S2[0], B, TD, TLI);
438 //===---------------------------------------===//
439 // 'strto*' Optimizations. This handles strtol, strtod, strtof, strtoul, etc.
441 struct StrToOpt : public LibCallOptimization {
442 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
443 FunctionType *FT = Callee->getFunctionType();
444 if ((FT->getNumParams() != 2 && FT->getNumParams() != 3) ||
445 !FT->getParamType(0)->isPointerTy() ||
446 !FT->getParamType(1)->isPointerTy())
449 Value *EndPtr = CI->getArgOperand(1);
450 if (isa<ConstantPointerNull>(EndPtr)) {
451 // With a null EndPtr, this function won't capture the main argument.
452 // It would be readonly too, except that it still may write to errno.
453 Attributes::Builder B;
454 B.addAttribute(Attributes::NoCapture);
455 CI->addAttribute(1, Attributes::get(B));
462 //===---------------------------------------===//
463 // 'strspn' Optimizations
465 struct StrSpnOpt : public LibCallOptimization {
466 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
467 FunctionType *FT = Callee->getFunctionType();
468 if (FT->getNumParams() != 2 ||
469 FT->getParamType(0) != B.getInt8PtrTy() ||
470 FT->getParamType(1) != FT->getParamType(0) ||
471 !FT->getReturnType()->isIntegerTy())
475 bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
476 bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
478 // strspn(s, "") -> 0
479 // strspn("", s) -> 0
480 if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
481 return Constant::getNullValue(CI->getType());
484 if (HasS1 && HasS2) {
485 size_t Pos = S1.find_first_not_of(S2);
486 if (Pos == StringRef::npos) Pos = S1.size();
487 return ConstantInt::get(CI->getType(), Pos);
494 //===---------------------------------------===//
495 // 'strcspn' Optimizations
497 struct StrCSpnOpt : public LibCallOptimization {
498 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
499 FunctionType *FT = Callee->getFunctionType();
500 if (FT->getNumParams() != 2 ||
501 FT->getParamType(0) != B.getInt8PtrTy() ||
502 FT->getParamType(1) != FT->getParamType(0) ||
503 !FT->getReturnType()->isIntegerTy())
507 bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
508 bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
510 // strcspn("", s) -> 0
511 if (HasS1 && S1.empty())
512 return Constant::getNullValue(CI->getType());
515 if (HasS1 && HasS2) {
516 size_t Pos = S1.find_first_of(S2);
517 if (Pos == StringRef::npos) Pos = S1.size();
518 return ConstantInt::get(CI->getType(), Pos);
521 // strcspn(s, "") -> strlen(s)
522 if (TD && HasS2 && S2.empty())
523 return EmitStrLen(CI->getArgOperand(0), B, TD, TLI);
529 //===---------------------------------------===//
530 // 'strstr' Optimizations
532 struct StrStrOpt : public LibCallOptimization {
533 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
534 FunctionType *FT = Callee->getFunctionType();
535 if (FT->getNumParams() != 2 ||
536 !FT->getParamType(0)->isPointerTy() ||
537 !FT->getParamType(1)->isPointerTy() ||
538 !FT->getReturnType()->isPointerTy())
541 // fold strstr(x, x) -> x.
542 if (CI->getArgOperand(0) == CI->getArgOperand(1))
543 return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
545 // fold strstr(a, b) == a -> strncmp(a, b, strlen(b)) == 0
546 if (TD && IsOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) {
547 Value *StrLen = EmitStrLen(CI->getArgOperand(1), B, TD, TLI);
550 Value *StrNCmp = EmitStrNCmp(CI->getArgOperand(0), CI->getArgOperand(1),
554 for (Value::use_iterator UI = CI->use_begin(), UE = CI->use_end();
556 ICmpInst *Old = cast<ICmpInst>(*UI++);
557 Value *Cmp = B.CreateICmp(Old->getPredicate(), StrNCmp,
558 ConstantInt::getNullValue(StrNCmp->getType()),
560 Old->replaceAllUsesWith(Cmp);
561 Old->eraseFromParent();
566 // See if either input string is a constant string.
567 StringRef SearchStr, ToFindStr;
568 bool HasStr1 = getConstantStringInfo(CI->getArgOperand(0), SearchStr);
569 bool HasStr2 = getConstantStringInfo(CI->getArgOperand(1), ToFindStr);
571 // fold strstr(x, "") -> x.
572 if (HasStr2 && ToFindStr.empty())
573 return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
575 // If both strings are known, constant fold it.
576 if (HasStr1 && HasStr2) {
577 std::string::size_type Offset = SearchStr.find(ToFindStr);
579 if (Offset == StringRef::npos) // strstr("foo", "bar") -> null
580 return Constant::getNullValue(CI->getType());
582 // strstr("abcd", "bc") -> gep((char*)"abcd", 1)
583 Value *Result = CastToCStr(CI->getArgOperand(0), B);
584 Result = B.CreateConstInBoundsGEP1_64(Result, Offset, "strstr");
585 return B.CreateBitCast(Result, CI->getType());
588 // fold strstr(x, "y") -> strchr(x, 'y').
589 if (HasStr2 && ToFindStr.size() == 1) {
590 Value *StrChr= EmitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TD, TLI);
591 return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : 0;
598 //===---------------------------------------===//
599 // 'memcmp' Optimizations
601 struct MemCmpOpt : public LibCallOptimization {
602 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
603 FunctionType *FT = Callee->getFunctionType();
604 if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
605 !FT->getParamType(1)->isPointerTy() ||
606 !FT->getReturnType()->isIntegerTy(32))
609 Value *LHS = CI->getArgOperand(0), *RHS = CI->getArgOperand(1);
611 if (LHS == RHS) // memcmp(s,s,x) -> 0
612 return Constant::getNullValue(CI->getType());
614 // Make sure we have a constant length.
615 ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
617 uint64_t Len = LenC->getZExtValue();
619 if (Len == 0) // memcmp(s1,s2,0) -> 0
620 return Constant::getNullValue(CI->getType());
622 // memcmp(S1,S2,1) -> *(unsigned char*)LHS - *(unsigned char*)RHS
624 Value *LHSV = B.CreateZExt(B.CreateLoad(CastToCStr(LHS, B), "lhsc"),
625 CI->getType(), "lhsv");
626 Value *RHSV = B.CreateZExt(B.CreateLoad(CastToCStr(RHS, B), "rhsc"),
627 CI->getType(), "rhsv");
628 return B.CreateSub(LHSV, RHSV, "chardiff");
631 // Constant folding: memcmp(x, y, l) -> cnst (all arguments are constant)
632 StringRef LHSStr, RHSStr;
633 if (getConstantStringInfo(LHS, LHSStr) &&
634 getConstantStringInfo(RHS, RHSStr)) {
635 // Make sure we're not reading out-of-bounds memory.
636 if (Len > LHSStr.size() || Len > RHSStr.size())
638 uint64_t Ret = memcmp(LHSStr.data(), RHSStr.data(), Len);
639 return ConstantInt::get(CI->getType(), Ret);
646 //===---------------------------------------===//
647 // 'memcpy' Optimizations
649 struct MemCpyOpt : public LibCallOptimization {
650 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
651 // These optimizations require DataLayout.
654 FunctionType *FT = Callee->getFunctionType();
655 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
656 !FT->getParamType(0)->isPointerTy() ||
657 !FT->getParamType(1)->isPointerTy() ||
658 FT->getParamType(2) != TD->getIntPtrType(*Context))
661 // memcpy(x, y, n) -> llvm.memcpy(x, y, n, 1)
662 B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
663 CI->getArgOperand(2), 1);
664 return CI->getArgOperand(0);
668 //===---------------------------------------===//
669 // 'memmove' Optimizations
671 struct MemMoveOpt : public LibCallOptimization {
672 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
673 // These optimizations require DataLayout.
676 FunctionType *FT = Callee->getFunctionType();
677 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
678 !FT->getParamType(0)->isPointerTy() ||
679 !FT->getParamType(1)->isPointerTy() ||
680 FT->getParamType(2) != TD->getIntPtrType(*Context))
683 // memmove(x, y, n) -> llvm.memmove(x, y, n, 1)
684 B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
685 CI->getArgOperand(2), 1);
686 return CI->getArgOperand(0);
690 //===---------------------------------------===//
691 // 'memset' Optimizations
693 struct MemSetOpt : public LibCallOptimization {
694 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
695 // These optimizations require DataLayout.
698 FunctionType *FT = Callee->getFunctionType();
699 if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
700 !FT->getParamType(0)->isPointerTy() ||
701 !FT->getParamType(1)->isIntegerTy() ||
702 FT->getParamType(2) != TD->getIntPtrType(*Context))
705 // memset(p, v, n) -> llvm.memset(p, v, n, 1)
706 Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
707 B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
708 return CI->getArgOperand(0);
712 //===----------------------------------------------------------------------===//
713 // Math Library Optimizations
714 //===----------------------------------------------------------------------===//
716 //===---------------------------------------===//
717 // Double -> Float Shrinking Optimizations for Unary Functions like 'floor'
719 struct UnaryDoubleFPOpt : public LibCallOptimization {
721 UnaryDoubleFPOpt(bool CheckReturnType): CheckRetType(CheckReturnType) {}
722 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
723 FunctionType *FT = Callee->getFunctionType();
724 if (FT->getNumParams() != 1 || !FT->getReturnType()->isDoubleTy() ||
725 !FT->getParamType(0)->isDoubleTy())
729 // Check if all the uses for function like 'sin' are converted to float.
730 for (Value::use_iterator UseI = CI->use_begin(); UseI != CI->use_end();
732 FPTruncInst *Cast = dyn_cast<FPTruncInst>(*UseI);
733 if (Cast == 0 || !Cast->getType()->isFloatTy())
738 // If this is something like 'floor((double)floatval)', convert to floorf.
739 FPExtInst *Cast = dyn_cast<FPExtInst>(CI->getArgOperand(0));
740 if (Cast == 0 || !Cast->getOperand(0)->getType()->isFloatTy())
743 // floor((double)floatval) -> (double)floorf(floatval)
744 Value *V = Cast->getOperand(0);
745 V = EmitUnaryFloatFnCall(V, Callee->getName(), B, Callee->getAttributes());
746 return B.CreateFPExt(V, B.getDoubleTy());
750 //===---------------------------------------===//
751 // 'cos*' Optimizations
752 struct CosOpt : public LibCallOptimization {
753 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
755 if (UnsafeFPShrink && Callee->getName() == "cos" &&
756 TLI->has(LibFunc::cosf)) {
757 UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
758 Ret = UnsafeUnaryDoubleFP.CallOptimizer(Callee, CI, B);
761 FunctionType *FT = Callee->getFunctionType();
762 // Just make sure this has 1 argument of FP type, which matches the
764 if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
765 !FT->getParamType(0)->isFloatingPointTy())
769 Value *Op1 = CI->getArgOperand(0);
770 if (BinaryOperator::isFNeg(Op1)) {
771 BinaryOperator *BinExpr = cast<BinaryOperator>(Op1);
772 return B.CreateCall(Callee, BinExpr->getOperand(1), "cos");
778 //===---------------------------------------===//
779 // 'pow*' Optimizations
781 struct PowOpt : public LibCallOptimization {
782 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
784 if (UnsafeFPShrink && Callee->getName() == "pow" &&
785 TLI->has(LibFunc::powf)) {
786 UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
787 Ret = UnsafeUnaryDoubleFP.CallOptimizer(Callee, CI, B);
790 FunctionType *FT = Callee->getFunctionType();
791 // Just make sure this has 2 arguments of the same FP type, which match the
793 if (FT->getNumParams() != 2 || FT->getReturnType() != FT->getParamType(0) ||
794 FT->getParamType(0) != FT->getParamType(1) ||
795 !FT->getParamType(0)->isFloatingPointTy())
798 Value *Op1 = CI->getArgOperand(0), *Op2 = CI->getArgOperand(1);
799 if (ConstantFP *Op1C = dyn_cast<ConstantFP>(Op1)) {
800 if (Op1C->isExactlyValue(1.0)) // pow(1.0, x) -> 1.0
802 if (Op1C->isExactlyValue(2.0)) // pow(2.0, x) -> exp2(x)
803 return EmitUnaryFloatFnCall(Op2, "exp2", B, Callee->getAttributes());
806 ConstantFP *Op2C = dyn_cast<ConstantFP>(Op2);
807 if (Op2C == 0) return Ret;
809 if (Op2C->getValueAPF().isZero()) // pow(x, 0.0) -> 1.0
810 return ConstantFP::get(CI->getType(), 1.0);
812 if (Op2C->isExactlyValue(0.5)) {
813 // Expand pow(x, 0.5) to (x == -infinity ? +infinity : fabs(sqrt(x))).
814 // This is faster than calling pow, and still handles negative zero
815 // and negative infinity correctly.
816 // TODO: In fast-math mode, this could be just sqrt(x).
817 // TODO: In finite-only mode, this could be just fabs(sqrt(x)).
818 Value *Inf = ConstantFP::getInfinity(CI->getType());
819 Value *NegInf = ConstantFP::getInfinity(CI->getType(), true);
820 Value *Sqrt = EmitUnaryFloatFnCall(Op1, "sqrt", B,
821 Callee->getAttributes());
822 Value *FAbs = EmitUnaryFloatFnCall(Sqrt, "fabs", B,
823 Callee->getAttributes());
824 Value *FCmp = B.CreateFCmpOEQ(Op1, NegInf);
825 Value *Sel = B.CreateSelect(FCmp, Inf, FAbs);
829 if (Op2C->isExactlyValue(1.0)) // pow(x, 1.0) -> x
831 if (Op2C->isExactlyValue(2.0)) // pow(x, 2.0) -> x*x
832 return B.CreateFMul(Op1, Op1, "pow2");
833 if (Op2C->isExactlyValue(-1.0)) // pow(x, -1.0) -> 1.0/x
834 return B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0),
840 //===---------------------------------------===//
841 // 'exp2' Optimizations
843 struct Exp2Opt : public LibCallOptimization {
844 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
846 if (UnsafeFPShrink && Callee->getName() == "exp2" &&
847 TLI->has(LibFunc::exp2)) {
848 UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
849 Ret = UnsafeUnaryDoubleFP.CallOptimizer(Callee, CI, B);
852 FunctionType *FT = Callee->getFunctionType();
853 // Just make sure this has 1 argument of FP type, which matches the
855 if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
856 !FT->getParamType(0)->isFloatingPointTy())
859 Value *Op = CI->getArgOperand(0);
860 // Turn exp2(sitofp(x)) -> ldexp(1.0, sext(x)) if sizeof(x) <= 32
861 // Turn exp2(uitofp(x)) -> ldexp(1.0, zext(x)) if sizeof(x) < 32
863 if (SIToFPInst *OpC = dyn_cast<SIToFPInst>(Op)) {
864 if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() <= 32)
865 LdExpArg = B.CreateSExt(OpC->getOperand(0), B.getInt32Ty());
866 } else if (UIToFPInst *OpC = dyn_cast<UIToFPInst>(Op)) {
867 if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() < 32)
868 LdExpArg = B.CreateZExt(OpC->getOperand(0), B.getInt32Ty());
873 if (Op->getType()->isFloatTy())
875 else if (Op->getType()->isDoubleTy())
880 Constant *One = ConstantFP::get(*Context, APFloat(1.0f));
881 if (!Op->getType()->isFloatTy())
882 One = ConstantExpr::getFPExtend(One, Op->getType());
884 Module *M = Caller->getParent();
885 Value *Callee = M->getOrInsertFunction(Name, Op->getType(),
887 B.getInt32Ty(), NULL);
888 CallInst *CI = B.CreateCall2(Callee, One, LdExpArg);
889 if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts()))
890 CI->setCallingConv(F->getCallingConv());
898 //===----------------------------------------------------------------------===//
899 // Integer Optimizations
900 //===----------------------------------------------------------------------===//
902 //===---------------------------------------===//
903 // 'ffs*' Optimizations
905 struct FFSOpt : public LibCallOptimization {
906 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
907 FunctionType *FT = Callee->getFunctionType();
908 // Just make sure this has 2 arguments of the same FP type, which match the
910 if (FT->getNumParams() != 1 ||
911 !FT->getReturnType()->isIntegerTy(32) ||
912 !FT->getParamType(0)->isIntegerTy())
915 Value *Op = CI->getArgOperand(0);
918 if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
919 if (CI->getValue() == 0) // ffs(0) -> 0.
920 return Constant::getNullValue(CI->getType());
921 // ffs(c) -> cttz(c)+1
922 return B.getInt32(CI->getValue().countTrailingZeros() + 1);
925 // ffs(x) -> x != 0 ? (i32)llvm.cttz(x)+1 : 0
926 Type *ArgType = Op->getType();
927 Value *F = Intrinsic::getDeclaration(Callee->getParent(),
928 Intrinsic::cttz, ArgType);
929 Value *V = B.CreateCall2(F, Op, B.getFalse(), "cttz");
930 V = B.CreateAdd(V, ConstantInt::get(V->getType(), 1));
931 V = B.CreateIntCast(V, B.getInt32Ty(), false);
933 Value *Cond = B.CreateICmpNE(Op, Constant::getNullValue(ArgType));
934 return B.CreateSelect(Cond, V, B.getInt32(0));
938 //===---------------------------------------===//
939 // 'isdigit' Optimizations
941 struct IsDigitOpt : public LibCallOptimization {
942 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
943 FunctionType *FT = Callee->getFunctionType();
944 // We require integer(i32)
945 if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
946 !FT->getParamType(0)->isIntegerTy(32))
949 // isdigit(c) -> (c-'0') <u 10
950 Value *Op = CI->getArgOperand(0);
951 Op = B.CreateSub(Op, B.getInt32('0'), "isdigittmp");
952 Op = B.CreateICmpULT(Op, B.getInt32(10), "isdigit");
953 return B.CreateZExt(Op, CI->getType());
957 //===---------------------------------------===//
958 // 'isascii' Optimizations
960 struct IsAsciiOpt : public LibCallOptimization {
961 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
962 FunctionType *FT = Callee->getFunctionType();
963 // We require integer(i32)
964 if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
965 !FT->getParamType(0)->isIntegerTy(32))
968 // isascii(c) -> c <u 128
969 Value *Op = CI->getArgOperand(0);
970 Op = B.CreateICmpULT(Op, B.getInt32(128), "isascii");
971 return B.CreateZExt(Op, CI->getType());
975 //===---------------------------------------===//
976 // 'abs', 'labs', 'llabs' Optimizations
978 struct AbsOpt : public LibCallOptimization {
979 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
980 FunctionType *FT = Callee->getFunctionType();
981 // We require integer(integer) where the types agree.
982 if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
983 FT->getParamType(0) != FT->getReturnType())
986 // abs(x) -> x >s -1 ? x : -x
987 Value *Op = CI->getArgOperand(0);
988 Value *Pos = B.CreateICmpSGT(Op, Constant::getAllOnesValue(Op->getType()),
990 Value *Neg = B.CreateNeg(Op, "neg");
991 return B.CreateSelect(Pos, Op, Neg);
996 //===---------------------------------------===//
997 // 'toascii' Optimizations
999 struct ToAsciiOpt : public LibCallOptimization {
1000 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1001 FunctionType *FT = Callee->getFunctionType();
1002 // We require i32(i32)
1003 if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
1004 !FT->getParamType(0)->isIntegerTy(32))
1007 // isascii(c) -> c & 0x7f
1008 return B.CreateAnd(CI->getArgOperand(0),
1009 ConstantInt::get(CI->getType(),0x7F));
1013 //===----------------------------------------------------------------------===//
1014 // Formatting and IO Optimizations
1015 //===----------------------------------------------------------------------===//
1017 //===---------------------------------------===//
1018 // 'printf' Optimizations
1020 struct PrintFOpt : public LibCallOptimization {
1021 Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
1023 // Check for a fixed format string.
1024 StringRef FormatStr;
1025 if (!getConstantStringInfo(CI->getArgOperand(0), FormatStr))
1028 // Empty format string -> noop.
1029 if (FormatStr.empty()) // Tolerate printf's declared void.
1030 return CI->use_empty() ? (Value*)CI :
1031 ConstantInt::get(CI->getType(), 0);
1033 // Do not do any of the following transformations if the printf return value
1034 // is used, in general the printf return value is not compatible with either
1035 // putchar() or puts().
1036 if (!CI->use_empty())
1039 // printf("x") -> putchar('x'), even for '%'.
1040 if (FormatStr.size() == 1) {
1041 Value *Res = EmitPutChar(B.getInt32(FormatStr[0]), B, TD, TLI);
1042 if (CI->use_empty() || !Res) return Res;
1043 return B.CreateIntCast(Res, CI->getType(), true);
1046 // printf("foo\n") --> puts("foo")
1047 if (FormatStr[FormatStr.size()-1] == '\n' &&
1048 FormatStr.find('%') == std::string::npos) { // no format characters.
1049 // Create a string literal with no \n on it. We expect the constant merge
1050 // pass to be run after this pass, to merge duplicate strings.
1051 FormatStr = FormatStr.drop_back();
1052 Value *GV = B.CreateGlobalString(FormatStr, "str");
1053 Value *NewCI = EmitPutS(GV, B, TD, TLI);
1054 return (CI->use_empty() || !NewCI) ?
1056 ConstantInt::get(CI->getType(), FormatStr.size()+1);
1059 // Optimize specific format strings.
1060 // printf("%c", chr) --> putchar(chr)
1061 if (FormatStr == "%c" && CI->getNumArgOperands() > 1 &&
1062 CI->getArgOperand(1)->getType()->isIntegerTy()) {
1063 Value *Res = EmitPutChar(CI->getArgOperand(1), B, TD, TLI);
1065 if (CI->use_empty() || !Res) return Res;
1066 return B.CreateIntCast(Res, CI->getType(), true);
1069 // printf("%s\n", str) --> puts(str)
1070 if (FormatStr == "%s\n" && CI->getNumArgOperands() > 1 &&
1071 CI->getArgOperand(1)->getType()->isPointerTy()) {
1072 return EmitPutS(CI->getArgOperand(1), B, TD, TLI);
1077 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1078 // Require one fixed pointer argument and an integer/void result.
1079 FunctionType *FT = Callee->getFunctionType();
1080 if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
1081 !(FT->getReturnType()->isIntegerTy() ||
1082 FT->getReturnType()->isVoidTy()))
1085 if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
1089 // printf(format, ...) -> iprintf(format, ...) if no floating point
1091 if (TLI->has(LibFunc::iprintf) && !CallHasFloatingPointArgument(CI)) {
1092 Module *M = B.GetInsertBlock()->getParent()->getParent();
1093 Constant *IPrintFFn =
1094 M->getOrInsertFunction("iprintf", FT, Callee->getAttributes());
1095 CallInst *New = cast<CallInst>(CI->clone());
1096 New->setCalledFunction(IPrintFFn);
1104 //===---------------------------------------===//
1105 // 'sprintf' Optimizations
1107 struct SPrintFOpt : public LibCallOptimization {
1108 Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
1110 // Check for a fixed format string.
1111 StringRef FormatStr;
1112 if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
1115 // If we just have a format string (nothing else crazy) transform it.
1116 if (CI->getNumArgOperands() == 2) {
1117 // Make sure there's no % in the constant array. We could try to handle
1118 // %% -> % in the future if we cared.
1119 for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
1120 if (FormatStr[i] == '%')
1121 return 0; // we found a format specifier, bail out.
1123 // These optimizations require DataLayout.
1126 // sprintf(str, fmt) -> llvm.memcpy(str, fmt, strlen(fmt)+1, 1)
1127 B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
1128 ConstantInt::get(TD->getIntPtrType(*Context), // Copy the
1129 FormatStr.size() + 1), 1); // nul byte.
1130 return ConstantInt::get(CI->getType(), FormatStr.size());
1133 // The remaining optimizations require the format string to be "%s" or "%c"
1134 // and have an extra operand.
1135 if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
1136 CI->getNumArgOperands() < 3)
1139 // Decode the second character of the format string.
1140 if (FormatStr[1] == 'c') {
1141 // sprintf(dst, "%c", chr) --> *(i8*)dst = chr; *((i8*)dst+1) = 0
1142 if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
1143 Value *V = B.CreateTrunc(CI->getArgOperand(2), B.getInt8Ty(), "char");
1144 Value *Ptr = CastToCStr(CI->getArgOperand(0), B);
1145 B.CreateStore(V, Ptr);
1146 Ptr = B.CreateGEP(Ptr, B.getInt32(1), "nul");
1147 B.CreateStore(B.getInt8(0), Ptr);
1149 return ConstantInt::get(CI->getType(), 1);
1152 if (FormatStr[1] == 's') {
1153 // These optimizations require DataLayout.
1156 // sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1)
1157 if (!CI->getArgOperand(2)->getType()->isPointerTy()) return 0;
1159 Value *Len = EmitStrLen(CI->getArgOperand(2), B, TD, TLI);
1162 Value *IncLen = B.CreateAdd(Len,
1163 ConstantInt::get(Len->getType(), 1),
1165 B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(2), IncLen, 1);
1167 // The sprintf result is the unincremented number of bytes in the string.
1168 return B.CreateIntCast(Len, CI->getType(), false);
1173 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1174 // Require two fixed pointer arguments and an integer result.
1175 FunctionType *FT = Callee->getFunctionType();
1176 if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
1177 !FT->getParamType(1)->isPointerTy() ||
1178 !FT->getReturnType()->isIntegerTy())
1181 if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
1185 // sprintf(str, format, ...) -> siprintf(str, format, ...) if no floating
1187 if (TLI->has(LibFunc::siprintf) && !CallHasFloatingPointArgument(CI)) {
1188 Module *M = B.GetInsertBlock()->getParent()->getParent();
1189 Constant *SIPrintFFn =
1190 M->getOrInsertFunction("siprintf", FT, Callee->getAttributes());
1191 CallInst *New = cast<CallInst>(CI->clone());
1192 New->setCalledFunction(SIPrintFFn);
1200 //===---------------------------------------===//
1201 // 'fwrite' Optimizations
1203 struct FWriteOpt : public LibCallOptimization {
1204 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1205 // Require a pointer, an integer, an integer, a pointer, returning integer.
1206 FunctionType *FT = Callee->getFunctionType();
1207 if (FT->getNumParams() != 4 || !FT->getParamType(0)->isPointerTy() ||
1208 !FT->getParamType(1)->isIntegerTy() ||
1209 !FT->getParamType(2)->isIntegerTy() ||
1210 !FT->getParamType(3)->isPointerTy() ||
1211 !FT->getReturnType()->isIntegerTy())
1214 // Get the element size and count.
1215 ConstantInt *SizeC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
1216 ConstantInt *CountC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
1217 if (!SizeC || !CountC) return 0;
1218 uint64_t Bytes = SizeC->getZExtValue()*CountC->getZExtValue();
1220 // If this is writing zero records, remove the call (it's a noop).
1222 return ConstantInt::get(CI->getType(), 0);
1224 // If this is writing one byte, turn it into fputc.
1225 // This optimisation is only valid, if the return value is unused.
1226 if (Bytes == 1 && CI->use_empty()) { // fwrite(S,1,1,F) -> fputc(S[0],F)
1227 Value *Char = B.CreateLoad(CastToCStr(CI->getArgOperand(0), B), "char");
1228 Value *NewCI = EmitFPutC(Char, CI->getArgOperand(3), B, TD, TLI);
1229 return NewCI ? ConstantInt::get(CI->getType(), 1) : 0;
1236 //===---------------------------------------===//
1237 // 'fputs' Optimizations
1239 struct FPutsOpt : public LibCallOptimization {
1240 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1241 // These optimizations require DataLayout.
1244 // Require two pointers. Also, we can't optimize if return value is used.
1245 FunctionType *FT = Callee->getFunctionType();
1246 if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
1247 !FT->getParamType(1)->isPointerTy() ||
1251 // fputs(s,F) --> fwrite(s,1,strlen(s),F)
1252 uint64_t Len = GetStringLength(CI->getArgOperand(0));
1254 // Known to have no uses (see above).
1255 return EmitFWrite(CI->getArgOperand(0),
1256 ConstantInt::get(TD->getIntPtrType(*Context), Len-1),
1257 CI->getArgOperand(1), B, TD, TLI);
1261 //===---------------------------------------===//
1262 // 'fprintf' Optimizations
1264 struct FPrintFOpt : public LibCallOptimization {
1265 Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
1267 // All the optimizations depend on the format string.
1268 StringRef FormatStr;
1269 if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
1272 // fprintf(F, "foo") --> fwrite("foo", 3, 1, F)
1273 if (CI->getNumArgOperands() == 2) {
1274 for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
1275 if (FormatStr[i] == '%') // Could handle %% -> % if we cared.
1276 return 0; // We found a format specifier.
1278 // These optimizations require DataLayout.
1281 Value *NewCI = EmitFWrite(CI->getArgOperand(1),
1282 ConstantInt::get(TD->getIntPtrType(*Context),
1284 CI->getArgOperand(0), B, TD, TLI);
1285 return NewCI ? ConstantInt::get(CI->getType(), FormatStr.size()) : 0;
1288 // The remaining optimizations require the format string to be "%s" or "%c"
1289 // and have an extra operand.
1290 if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
1291 CI->getNumArgOperands() < 3)
1294 // Decode the second character of the format string.
1295 if (FormatStr[1] == 'c') {
1296 // fprintf(F, "%c", chr) --> fputc(chr, F)
1297 if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
1298 Value *NewCI = EmitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B,
1300 return NewCI ? ConstantInt::get(CI->getType(), 1) : 0;
1303 if (FormatStr[1] == 's') {
1304 // fprintf(F, "%s", str) --> fputs(str, F)
1305 if (!CI->getArgOperand(2)->getType()->isPointerTy() || !CI->use_empty())
1307 return EmitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TD, TLI);
1312 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1313 // Require two fixed paramters as pointers and integer result.
1314 FunctionType *FT = Callee->getFunctionType();
1315 if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
1316 !FT->getParamType(1)->isPointerTy() ||
1317 !FT->getReturnType()->isIntegerTy())
1320 if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
1324 // fprintf(stream, format, ...) -> fiprintf(stream, format, ...) if no
1325 // floating point arguments.
1326 if (TLI->has(LibFunc::fiprintf) && !CallHasFloatingPointArgument(CI)) {
1327 Module *M = B.GetInsertBlock()->getParent()->getParent();
1328 Constant *FIPrintFFn =
1329 M->getOrInsertFunction("fiprintf", FT, Callee->getAttributes());
1330 CallInst *New = cast<CallInst>(CI->clone());
1331 New->setCalledFunction(FIPrintFFn);
1339 //===---------------------------------------===//
1340 // 'puts' Optimizations
1342 struct PutsOpt : public LibCallOptimization {
1343 virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
1344 // Require one fixed pointer argument and an integer/void result.
1345 FunctionType *FT = Callee->getFunctionType();
1346 if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
1347 !(FT->getReturnType()->isIntegerTy() ||
1348 FT->getReturnType()->isVoidTy()))
1351 // Check for a constant string.
1353 if (!getConstantStringInfo(CI->getArgOperand(0), Str))
1356 if (Str.empty() && CI->use_empty()) {
1357 // puts("") -> putchar('\n')
1358 Value *Res = EmitPutChar(B.getInt32('\n'), B, TD, TLI);
1359 if (CI->use_empty() || !Res) return Res;
1360 return B.CreateIntCast(Res, CI->getType(), true);
1367 } // end anonymous namespace.
1369 //===----------------------------------------------------------------------===//
1370 // SimplifyLibCalls Pass Implementation
1371 //===----------------------------------------------------------------------===//
1374 /// This pass optimizes well known library functions from libc and libm.
1376 class SimplifyLibCalls : public FunctionPass {
1377 TargetLibraryInfo *TLI;
1379 StringMap<LibCallOptimization*> Optimizations;
1380 // String and Memory LibCall Optimizations
1381 StrCmpOpt StrCmp; StrNCmpOpt StrNCmp;
1382 StrCpyOpt StrCpy; StrCpyOpt StrCpyChk;
1383 StpCpyOpt StpCpy; StpCpyOpt StpCpyChk;
1385 StrLenOpt StrLen; StrPBrkOpt StrPBrk;
1386 StrToOpt StrTo; StrSpnOpt StrSpn; StrCSpnOpt StrCSpn; StrStrOpt StrStr;
1387 MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
1388 // Math Library Optimizations
1389 CosOpt Cos; PowOpt Pow; Exp2Opt Exp2;
1390 UnaryDoubleFPOpt UnaryDoubleFP, UnsafeUnaryDoubleFP;
1391 // Integer Optimizations
1392 FFSOpt FFS; AbsOpt Abs; IsDigitOpt IsDigit; IsAsciiOpt IsAscii;
1394 // Formatting and IO Optimizations
1395 SPrintFOpt SPrintF; PrintFOpt PrintF;
1396 FWriteOpt FWrite; FPutsOpt FPuts; FPrintFOpt FPrintF;
1399 bool Modified; // This is only used by doInitialization.
1401 static char ID; // Pass identification
1402 SimplifyLibCalls() : FunctionPass(ID), StrCpy(false), StrCpyChk(true),
1403 StpCpy(false), StpCpyChk(true),
1404 UnaryDoubleFP(false), UnsafeUnaryDoubleFP(true) {
1405 initializeSimplifyLibCallsPass(*PassRegistry::getPassRegistry());
1407 void AddOpt(LibFunc::Func F, LibCallOptimization* Opt);
1408 void AddOpt(LibFunc::Func F1, LibFunc::Func F2, LibCallOptimization* Opt);
1410 void InitOptimizations();
1411 bool runOnFunction(Function &F);
1413 void setDoesNotAccessMemory(Function &F);
1414 void setOnlyReadsMemory(Function &F);
1415 void setDoesNotThrow(Function &F);
1416 void setDoesNotCapture(Function &F, unsigned n);
1417 void setDoesNotAlias(Function &F, unsigned n);
1418 bool doInitialization(Module &M);
1420 void inferPrototypeAttributes(Function &F);
1421 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
1422 AU.addRequired<TargetLibraryInfo>();
1425 } // end anonymous namespace.
1427 char SimplifyLibCalls::ID = 0;
1429 INITIALIZE_PASS_BEGIN(SimplifyLibCalls, "simplify-libcalls",
1430 "Simplify well-known library calls", false, false)
1431 INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfo)
1432 INITIALIZE_PASS_END(SimplifyLibCalls, "simplify-libcalls",
1433 "Simplify well-known library calls", false, false)
1435 // Public interface to the Simplify LibCalls pass.
1436 FunctionPass *llvm::createSimplifyLibCallsPass() {
1437 return new SimplifyLibCalls();
1440 void SimplifyLibCalls::AddOpt(LibFunc::Func F, LibCallOptimization* Opt) {
1442 Optimizations[TLI->getName(F)] = Opt;
1445 void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2,
1446 LibCallOptimization* Opt) {
1447 if (TLI->has(F1) && TLI->has(F2))
1448 Optimizations[TLI->getName(F1)] = Opt;
1451 /// Optimizations - Populate the Optimizations map with all the optimizations
1453 void SimplifyLibCalls::InitOptimizations() {
1454 // String and Memory LibCall Optimizations
1455 Optimizations["strcmp"] = &StrCmp;
1456 Optimizations["strncmp"] = &StrNCmp;
1457 Optimizations["strcpy"] = &StrCpy;
1458 Optimizations["strncpy"] = &StrNCpy;
1459 Optimizations["stpcpy"] = &StpCpy;
1460 Optimizations["strlen"] = &StrLen;
1461 Optimizations["strpbrk"] = &StrPBrk;
1462 Optimizations["strtol"] = &StrTo;
1463 Optimizations["strtod"] = &StrTo;
1464 Optimizations["strtof"] = &StrTo;
1465 Optimizations["strtoul"] = &StrTo;
1466 Optimizations["strtoll"] = &StrTo;
1467 Optimizations["strtold"] = &StrTo;
1468 Optimizations["strtoull"] = &StrTo;
1469 Optimizations["strspn"] = &StrSpn;
1470 Optimizations["strcspn"] = &StrCSpn;
1471 Optimizations["strstr"] = &StrStr;
1472 Optimizations["memcmp"] = &MemCmp;
1473 AddOpt(LibFunc::memcpy, &MemCpy);
1474 Optimizations["memmove"] = &MemMove;
1475 AddOpt(LibFunc::memset, &MemSet);
1477 // _chk variants of String and Memory LibCall Optimizations.
1478 Optimizations["__strcpy_chk"] = &StrCpyChk;
1479 Optimizations["__stpcpy_chk"] = &StpCpyChk;
1481 // Math Library Optimizations
1482 Optimizations["cosf"] = &Cos;
1483 Optimizations["cos"] = &Cos;
1484 Optimizations["cosl"] = &Cos;
1485 Optimizations["powf"] = &Pow;
1486 Optimizations["pow"] = &Pow;
1487 Optimizations["powl"] = &Pow;
1488 Optimizations["llvm.pow.f32"] = &Pow;
1489 Optimizations["llvm.pow.f64"] = &Pow;
1490 Optimizations["llvm.pow.f80"] = &Pow;
1491 Optimizations["llvm.pow.f128"] = &Pow;
1492 Optimizations["llvm.pow.ppcf128"] = &Pow;
1493 Optimizations["exp2l"] = &Exp2;
1494 Optimizations["exp2"] = &Exp2;
1495 Optimizations["exp2f"] = &Exp2;
1496 Optimizations["llvm.exp2.ppcf128"] = &Exp2;
1497 Optimizations["llvm.exp2.f128"] = &Exp2;
1498 Optimizations["llvm.exp2.f80"] = &Exp2;
1499 Optimizations["llvm.exp2.f64"] = &Exp2;
1500 Optimizations["llvm.exp2.f32"] = &Exp2;
1502 AddOpt(LibFunc::ceil, LibFunc::ceilf, &UnaryDoubleFP);
1503 AddOpt(LibFunc::fabs, LibFunc::fabsf, &UnaryDoubleFP);
1504 AddOpt(LibFunc::floor, LibFunc::floorf, &UnaryDoubleFP);
1505 AddOpt(LibFunc::rint, LibFunc::rintf, &UnaryDoubleFP);
1506 AddOpt(LibFunc::round, LibFunc::roundf, &UnaryDoubleFP);
1507 AddOpt(LibFunc::nearbyint, LibFunc::nearbyintf, &UnaryDoubleFP);
1508 AddOpt(LibFunc::trunc, LibFunc::truncf, &UnaryDoubleFP);
1510 if(UnsafeFPShrink) {
1511 AddOpt(LibFunc::acos, LibFunc::acosf, &UnsafeUnaryDoubleFP);
1512 AddOpt(LibFunc::acosh, LibFunc::acoshf, &UnsafeUnaryDoubleFP);
1513 AddOpt(LibFunc::asin, LibFunc::asinf, &UnsafeUnaryDoubleFP);
1514 AddOpt(LibFunc::asinh, LibFunc::asinhf, &UnsafeUnaryDoubleFP);
1515 AddOpt(LibFunc::atan, LibFunc::atanf, &UnsafeUnaryDoubleFP);
1516 AddOpt(LibFunc::atanh, LibFunc::atanhf, &UnsafeUnaryDoubleFP);
1517 AddOpt(LibFunc::cbrt, LibFunc::cbrtf, &UnsafeUnaryDoubleFP);
1518 AddOpt(LibFunc::cosh, LibFunc::coshf, &UnsafeUnaryDoubleFP);
1519 AddOpt(LibFunc::exp, LibFunc::expf, &UnsafeUnaryDoubleFP);
1520 AddOpt(LibFunc::exp10, LibFunc::exp10f, &UnsafeUnaryDoubleFP);
1521 AddOpt(LibFunc::expm1, LibFunc::expm1f, &UnsafeUnaryDoubleFP);
1522 AddOpt(LibFunc::log, LibFunc::logf, &UnsafeUnaryDoubleFP);
1523 AddOpt(LibFunc::log10, LibFunc::log10f, &UnsafeUnaryDoubleFP);
1524 AddOpt(LibFunc::log1p, LibFunc::log1pf, &UnsafeUnaryDoubleFP);
1525 AddOpt(LibFunc::log2, LibFunc::log2f, &UnsafeUnaryDoubleFP);
1526 AddOpt(LibFunc::logb, LibFunc::logbf, &UnsafeUnaryDoubleFP);
1527 AddOpt(LibFunc::sin, LibFunc::sinf, &UnsafeUnaryDoubleFP);
1528 AddOpt(LibFunc::sinh, LibFunc::sinhf, &UnsafeUnaryDoubleFP);
1529 AddOpt(LibFunc::sqrt, LibFunc::sqrtf, &UnsafeUnaryDoubleFP);
1530 AddOpt(LibFunc::tan, LibFunc::tanf, &UnsafeUnaryDoubleFP);
1531 AddOpt(LibFunc::tanh, LibFunc::tanhf, &UnsafeUnaryDoubleFP);
1534 // Integer Optimizations
1535 Optimizations["ffs"] = &FFS;
1536 Optimizations["ffsl"] = &FFS;
1537 Optimizations["ffsll"] = &FFS;
1538 Optimizations["abs"] = &Abs;
1539 Optimizations["labs"] = &Abs;
1540 Optimizations["llabs"] = &Abs;
1541 Optimizations["isdigit"] = &IsDigit;
1542 Optimizations["isascii"] = &IsAscii;
1543 Optimizations["toascii"] = &ToAscii;
1545 // Formatting and IO Optimizations
1546 Optimizations["sprintf"] = &SPrintF;
1547 Optimizations["printf"] = &PrintF;
1548 AddOpt(LibFunc::fwrite, &FWrite);
1549 AddOpt(LibFunc::fputs, &FPuts);
1550 Optimizations["fprintf"] = &FPrintF;
1551 Optimizations["puts"] = &Puts;
1555 /// runOnFunction - Top level algorithm.
1557 bool SimplifyLibCalls::runOnFunction(Function &F) {
1558 TLI = &getAnalysis<TargetLibraryInfo>();
1560 if (Optimizations.empty())
1561 InitOptimizations();
1563 const DataLayout *TD = getAnalysisIfAvailable<DataLayout>();
1565 IRBuilder<> Builder(F.getContext());
1567 bool Changed = false;
1568 for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
1569 for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ) {
1570 // Ignore non-calls.
1571 CallInst *CI = dyn_cast<CallInst>(I++);
1574 // Ignore indirect calls and calls to non-external functions.
1575 Function *Callee = CI->getCalledFunction();
1576 if (Callee == 0 || !Callee->isDeclaration() ||
1577 !(Callee->hasExternalLinkage() || Callee->hasDLLImportLinkage()))
1580 // Ignore unknown calls.
1581 LibCallOptimization *LCO = Optimizations.lookup(Callee->getName());
1584 // Set the builder to the instruction after the call.
1585 Builder.SetInsertPoint(BB, I);
1587 // Use debug location of CI for all new instructions.
1588 Builder.SetCurrentDebugLocation(CI->getDebugLoc());
1590 // Try to optimize this call.
1591 Value *Result = LCO->OptimizeCall(CI, TD, TLI, Builder);
1592 if (Result == 0) continue;
1594 DEBUG(dbgs() << "SimplifyLibCalls simplified: " << *CI;
1595 dbgs() << " into: " << *Result << "\n");
1597 // Something changed!
1601 // Inspect the instruction after the call (which was potentially just
1605 if (CI != Result && !CI->use_empty()) {
1606 CI->replaceAllUsesWith(Result);
1607 if (!Result->hasName())
1608 Result->takeName(CI);
1610 CI->eraseFromParent();
1616 // Utility methods for doInitialization.
1618 void SimplifyLibCalls::setDoesNotAccessMemory(Function &F) {
1619 if (!F.doesNotAccessMemory()) {
1620 F.setDoesNotAccessMemory();
1625 void SimplifyLibCalls::setOnlyReadsMemory(Function &F) {
1626 if (!F.onlyReadsMemory()) {
1627 F.setOnlyReadsMemory();
1632 void SimplifyLibCalls::setDoesNotThrow(Function &F) {
1633 if (!F.doesNotThrow()) {
1634 F.setDoesNotThrow();
1639 void SimplifyLibCalls::setDoesNotCapture(Function &F, unsigned n) {
1640 if (!F.doesNotCapture(n)) {
1641 F.setDoesNotCapture(n);
1646 void SimplifyLibCalls::setDoesNotAlias(Function &F, unsigned n) {
1647 if (!F.doesNotAlias(n)) {
1648 F.setDoesNotAlias(n);
1655 void SimplifyLibCalls::inferPrototypeAttributes(Function &F) {
1656 FunctionType *FTy = F.getFunctionType();
1658 StringRef Name = F.getName();
1661 if (Name == "strlen") {
1662 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1664 setOnlyReadsMemory(F);
1666 setDoesNotCapture(F, 1);
1667 } else if (Name == "strchr" ||
1668 Name == "strrchr") {
1669 if (FTy->getNumParams() != 2 ||
1670 !FTy->getParamType(0)->isPointerTy() ||
1671 !FTy->getParamType(1)->isIntegerTy())
1673 setOnlyReadsMemory(F);
1675 } else if (Name == "strcpy" ||
1681 Name == "strtoul" ||
1682 Name == "strtoll" ||
1683 Name == "strtold" ||
1684 Name == "strncat" ||
1685 Name == "strncpy" ||
1686 Name == "stpncpy" ||
1687 Name == "strtoull") {
1688 if (FTy->getNumParams() < 2 ||
1689 !FTy->getParamType(1)->isPointerTy())
1692 setDoesNotCapture(F, 2);
1693 } else if (Name == "strxfrm") {
1694 if (FTy->getNumParams() != 3 ||
1695 !FTy->getParamType(0)->isPointerTy() ||
1696 !FTy->getParamType(1)->isPointerTy())
1699 setDoesNotCapture(F, 1);
1700 setDoesNotCapture(F, 2);
1701 } else if (Name == "strcmp" ||
1703 Name == "strncmp" ||
1704 Name == "strcspn" ||
1705 Name == "strcoll" ||
1706 Name == "strcasecmp" ||
1707 Name == "strncasecmp") {
1708 if (FTy->getNumParams() < 2 ||
1709 !FTy->getParamType(0)->isPointerTy() ||
1710 !FTy->getParamType(1)->isPointerTy())
1712 setOnlyReadsMemory(F);
1714 setDoesNotCapture(F, 1);
1715 setDoesNotCapture(F, 2);
1716 } else if (Name == "strstr" ||
1717 Name == "strpbrk") {
1718 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1720 setOnlyReadsMemory(F);
1722 setDoesNotCapture(F, 2);
1723 } else if (Name == "strtok" ||
1724 Name == "strtok_r") {
1725 if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy())
1728 setDoesNotCapture(F, 2);
1729 } else if (Name == "scanf" ||
1731 Name == "setvbuf") {
1732 if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy())
1735 setDoesNotCapture(F, 1);
1736 } else if (Name == "strdup" ||
1737 Name == "strndup") {
1738 if (FTy->getNumParams() < 1 || !FTy->getReturnType()->isPointerTy() ||
1739 !FTy->getParamType(0)->isPointerTy())
1742 setDoesNotAlias(F, 0);
1743 setDoesNotCapture(F, 1);
1744 } else if (Name == "stat" ||
1746 Name == "sprintf" ||
1747 Name == "statvfs") {
1748 if (FTy->getNumParams() < 2 ||
1749 !FTy->getParamType(0)->isPointerTy() ||
1750 !FTy->getParamType(1)->isPointerTy())
1753 setDoesNotCapture(F, 1);
1754 setDoesNotCapture(F, 2);
1755 } else if (Name == "snprintf") {
1756 if (FTy->getNumParams() != 3 ||
1757 !FTy->getParamType(0)->isPointerTy() ||
1758 !FTy->getParamType(2)->isPointerTy())
1761 setDoesNotCapture(F, 1);
1762 setDoesNotCapture(F, 3);
1763 } else if (Name == "setitimer") {
1764 if (FTy->getNumParams() != 3 ||
1765 !FTy->getParamType(1)->isPointerTy() ||
1766 !FTy->getParamType(2)->isPointerTy())
1769 setDoesNotCapture(F, 2);
1770 setDoesNotCapture(F, 3);
1771 } else if (Name == "system") {
1772 if (FTy->getNumParams() != 1 ||
1773 !FTy->getParamType(0)->isPointerTy())
1775 // May throw; "system" is a valid pthread cancellation point.
1776 setDoesNotCapture(F, 1);
1780 if (Name == "malloc") {
1781 if (FTy->getNumParams() != 1 ||
1782 !FTy->getReturnType()->isPointerTy())
1785 setDoesNotAlias(F, 0);
1786 } else if (Name == "memcmp") {
1787 if (FTy->getNumParams() != 3 ||
1788 !FTy->getParamType(0)->isPointerTy() ||
1789 !FTy->getParamType(1)->isPointerTy())
1791 setOnlyReadsMemory(F);
1793 setDoesNotCapture(F, 1);
1794 setDoesNotCapture(F, 2);
1795 } else if (Name == "memchr" ||
1796 Name == "memrchr") {
1797 if (FTy->getNumParams() != 3)
1799 setOnlyReadsMemory(F);
1801 } else if (Name == "modf" ||
1805 Name == "memccpy" ||
1806 Name == "memmove") {
1807 if (FTy->getNumParams() < 2 ||
1808 !FTy->getParamType(1)->isPointerTy())
1811 setDoesNotCapture(F, 2);
1812 } else if (Name == "memalign") {
1813 if (!FTy->getReturnType()->isPointerTy())
1815 setDoesNotAlias(F, 0);
1816 } else if (Name == "mkdir" ||
1818 if (FTy->getNumParams() == 0 ||
1819 !FTy->getParamType(0)->isPointerTy())
1822 setDoesNotCapture(F, 1);
1826 if (Name == "realloc") {
1827 if (FTy->getNumParams() != 2 ||
1828 !FTy->getParamType(0)->isPointerTy() ||
1829 !FTy->getReturnType()->isPointerTy())
1832 setDoesNotAlias(F, 0);
1833 setDoesNotCapture(F, 1);
1834 } else if (Name == "read") {
1835 if (FTy->getNumParams() != 3 ||
1836 !FTy->getParamType(1)->isPointerTy())
1838 // May throw; "read" is a valid pthread cancellation point.
1839 setDoesNotCapture(F, 2);
1840 } else if (Name == "rmdir" ||
1843 Name == "realpath") {
1844 if (FTy->getNumParams() < 1 ||
1845 !FTy->getParamType(0)->isPointerTy())
1848 setDoesNotCapture(F, 1);
1849 } else if (Name == "rename" ||
1850 Name == "readlink") {
1851 if (FTy->getNumParams() < 2 ||
1852 !FTy->getParamType(0)->isPointerTy() ||
1853 !FTy->getParamType(1)->isPointerTy())
1856 setDoesNotCapture(F, 1);
1857 setDoesNotCapture(F, 2);
1861 if (Name == "write") {
1862 if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy())
1864 // May throw; "write" is a valid pthread cancellation point.
1865 setDoesNotCapture(F, 2);
1869 if (Name == "bcopy") {
1870 if (FTy->getNumParams() != 3 ||
1871 !FTy->getParamType(0)->isPointerTy() ||
1872 !FTy->getParamType(1)->isPointerTy())
1875 setDoesNotCapture(F, 1);
1876 setDoesNotCapture(F, 2);
1877 } else if (Name == "bcmp") {
1878 if (FTy->getNumParams() != 3 ||
1879 !FTy->getParamType(0)->isPointerTy() ||
1880 !FTy->getParamType(1)->isPointerTy())
1883 setOnlyReadsMemory(F);
1884 setDoesNotCapture(F, 1);
1885 setDoesNotCapture(F, 2);
1886 } else if (Name == "bzero") {
1887 if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
1890 setDoesNotCapture(F, 1);
1894 if (Name == "calloc") {
1895 if (FTy->getNumParams() != 2 ||
1896 !FTy->getReturnType()->isPointerTy())
1899 setDoesNotAlias(F, 0);
1900 } else if (Name == "chmod" ||
1902 Name == "ctermid" ||
1903 Name == "clearerr" ||
1904 Name == "closedir") {
1905 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
1908 setDoesNotCapture(F, 1);
1912 if (Name == "atoi" ||
1916 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1919 setOnlyReadsMemory(F);
1920 setDoesNotCapture(F, 1);
1921 } else if (Name == "access") {
1922 if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
1925 setDoesNotCapture(F, 1);
1929 if (Name == "fopen") {
1930 if (FTy->getNumParams() != 2 ||
1931 !FTy->getReturnType()->isPointerTy() ||
1932 !FTy->getParamType(0)->isPointerTy() ||
1933 !FTy->getParamType(1)->isPointerTy())
1936 setDoesNotAlias(F, 0);
1937 setDoesNotCapture(F, 1);
1938 setDoesNotCapture(F, 2);
1939 } else if (Name == "fdopen") {
1940 if (FTy->getNumParams() != 2 ||
1941 !FTy->getReturnType()->isPointerTy() ||
1942 !FTy->getParamType(1)->isPointerTy())
1945 setDoesNotAlias(F, 0);
1946 setDoesNotCapture(F, 2);
1947 } else if (Name == "feof" ||
1957 Name == "fsetpos" ||
1958 Name == "flockfile" ||
1959 Name == "funlockfile" ||
1960 Name == "ftrylockfile") {
1961 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
1964 setDoesNotCapture(F, 1);
1965 } else if (Name == "ferror") {
1966 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
1969 setDoesNotCapture(F, 1);
1970 setOnlyReadsMemory(F);
1971 } else if (Name == "fputc" ||
1976 Name == "fstatvfs") {
1977 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
1980 setDoesNotCapture(F, 2);
1981 } else if (Name == "fgets") {
1982 if (FTy->getNumParams() != 3 ||
1983 !FTy->getParamType(0)->isPointerTy() ||
1984 !FTy->getParamType(2)->isPointerTy())
1987 setDoesNotCapture(F, 3);
1988 } else if (Name == "fread" ||
1990 if (FTy->getNumParams() != 4 ||
1991 !FTy->getParamType(0)->isPointerTy() ||
1992 !FTy->getParamType(3)->isPointerTy())
1995 setDoesNotCapture(F, 1);
1996 setDoesNotCapture(F, 4);
1997 } else if (Name == "fputs" ||
1999 Name == "fprintf" ||
2000 Name == "fgetpos") {
2001 if (FTy->getNumParams() < 2 ||
2002 !FTy->getParamType(0)->isPointerTy() ||
2003 !FTy->getParamType(1)->isPointerTy())
2006 setDoesNotCapture(F, 1);
2007 setDoesNotCapture(F, 2);
2011 if (Name == "getc" ||
2012 Name == "getlogin_r" ||
2013 Name == "getc_unlocked") {
2014 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
2017 setDoesNotCapture(F, 1);
2018 } else if (Name == "getenv") {
2019 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2022 setOnlyReadsMemory(F);
2023 setDoesNotCapture(F, 1);
2024 } else if (Name == "gets" ||
2025 Name == "getchar") {
2027 } else if (Name == "getitimer") {
2028 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2031 setDoesNotCapture(F, 2);
2032 } else if (Name == "getpwnam") {
2033 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2036 setDoesNotCapture(F, 1);
2040 if (Name == "ungetc") {
2041 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2044 setDoesNotCapture(F, 2);
2045 } else if (Name == "uname" ||
2047 Name == "unsetenv") {
2048 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2051 setDoesNotCapture(F, 1);
2052 } else if (Name == "utime" ||
2054 if (FTy->getNumParams() != 2 ||
2055 !FTy->getParamType(0)->isPointerTy() ||
2056 !FTy->getParamType(1)->isPointerTy())
2059 setDoesNotCapture(F, 1);
2060 setDoesNotCapture(F, 2);
2064 if (Name == "putc") {
2065 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2068 setDoesNotCapture(F, 2);
2069 } else if (Name == "puts" ||
2072 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2075 setDoesNotCapture(F, 1);
2076 } else if (Name == "pread" ||
2078 if (FTy->getNumParams() != 4 || !FTy->getParamType(1)->isPointerTy())
2080 // May throw; these are valid pthread cancellation points.
2081 setDoesNotCapture(F, 2);
2082 } else if (Name == "putchar") {
2084 } else if (Name == "popen") {
2085 if (FTy->getNumParams() != 2 ||
2086 !FTy->getReturnType()->isPointerTy() ||
2087 !FTy->getParamType(0)->isPointerTy() ||
2088 !FTy->getParamType(1)->isPointerTy())
2091 setDoesNotAlias(F, 0);
2092 setDoesNotCapture(F, 1);
2093 setDoesNotCapture(F, 2);
2094 } else if (Name == "pclose") {
2095 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2098 setDoesNotCapture(F, 1);
2102 if (Name == "vscanf") {
2103 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2106 setDoesNotCapture(F, 1);
2107 } else if (Name == "vsscanf" ||
2108 Name == "vfscanf") {
2109 if (FTy->getNumParams() != 3 ||
2110 !FTy->getParamType(1)->isPointerTy() ||
2111 !FTy->getParamType(2)->isPointerTy())
2114 setDoesNotCapture(F, 1);
2115 setDoesNotCapture(F, 2);
2116 } else if (Name == "valloc") {
2117 if (!FTy->getReturnType()->isPointerTy())
2120 setDoesNotAlias(F, 0);
2121 } else if (Name == "vprintf") {
2122 if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
2125 setDoesNotCapture(F, 1);
2126 } else if (Name == "vfprintf" ||
2127 Name == "vsprintf") {
2128 if (FTy->getNumParams() != 3 ||
2129 !FTy->getParamType(0)->isPointerTy() ||
2130 !FTy->getParamType(1)->isPointerTy())
2133 setDoesNotCapture(F, 1);
2134 setDoesNotCapture(F, 2);
2135 } else if (Name == "vsnprintf") {
2136 if (FTy->getNumParams() != 4 ||
2137 !FTy->getParamType(0)->isPointerTy() ||
2138 !FTy->getParamType(2)->isPointerTy())
2141 setDoesNotCapture(F, 1);
2142 setDoesNotCapture(F, 3);
2146 if (Name == "open") {
2147 if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
2149 // May throw; "open" is a valid pthread cancellation point.
2150 setDoesNotCapture(F, 1);
2151 } else if (Name == "opendir") {
2152 if (FTy->getNumParams() != 1 ||
2153 !FTy->getReturnType()->isPointerTy() ||
2154 !FTy->getParamType(0)->isPointerTy())
2157 setDoesNotAlias(F, 0);
2158 setDoesNotCapture(F, 1);
2162 if (Name == "tmpfile") {
2163 if (!FTy->getReturnType()->isPointerTy())
2166 setDoesNotAlias(F, 0);
2167 } else if (Name == "times") {
2168 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2171 setDoesNotCapture(F, 1);
2175 if (Name == "htonl" ||
2178 setDoesNotAccessMemory(F);
2182 if (Name == "ntohl" ||
2185 setDoesNotAccessMemory(F);
2189 if (Name == "lstat") {
2190 if (FTy->getNumParams() != 2 ||
2191 !FTy->getParamType(0)->isPointerTy() ||
2192 !FTy->getParamType(1)->isPointerTy())
2195 setDoesNotCapture(F, 1);
2196 setDoesNotCapture(F, 2);
2197 } else if (Name == "lchown") {
2198 if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy())
2201 setDoesNotCapture(F, 1);
2205 if (Name == "qsort") {
2206 if (FTy->getNumParams() != 4 || !FTy->getParamType(3)->isPointerTy())
2208 // May throw; places call through function pointer.
2209 setDoesNotCapture(F, 4);
2213 if (Name == "__strdup" ||
2214 Name == "__strndup") {
2215 if (FTy->getNumParams() < 1 ||
2216 !FTy->getReturnType()->isPointerTy() ||
2217 !FTy->getParamType(0)->isPointerTy())
2220 setDoesNotAlias(F, 0);
2221 setDoesNotCapture(F, 1);
2222 } else if (Name == "__strtok_r") {
2223 if (FTy->getNumParams() != 3 ||
2224 !FTy->getParamType(1)->isPointerTy())
2227 setDoesNotCapture(F, 2);
2228 } else if (Name == "_IO_getc") {
2229 if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
2232 setDoesNotCapture(F, 1);
2233 } else if (Name == "_IO_putc") {
2234 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2237 setDoesNotCapture(F, 2);
2241 if (Name == "\1__isoc99_scanf") {
2242 if (FTy->getNumParams() < 1 ||
2243 !FTy->getParamType(0)->isPointerTy())
2246 setDoesNotCapture(F, 1);
2247 } else if (Name == "\1stat64" ||
2248 Name == "\1lstat64" ||
2249 Name == "\1statvfs64" ||
2250 Name == "\1__isoc99_sscanf") {
2251 if (FTy->getNumParams() < 1 ||
2252 !FTy->getParamType(0)->isPointerTy() ||
2253 !FTy->getParamType(1)->isPointerTy())
2256 setDoesNotCapture(F, 1);
2257 setDoesNotCapture(F, 2);
2258 } else if (Name == "\1fopen64") {
2259 if (FTy->getNumParams() != 2 ||
2260 !FTy->getReturnType()->isPointerTy() ||
2261 !FTy->getParamType(0)->isPointerTy() ||
2262 !FTy->getParamType(1)->isPointerTy())
2265 setDoesNotAlias(F, 0);
2266 setDoesNotCapture(F, 1);
2267 setDoesNotCapture(F, 2);
2268 } else if (Name == "\1fseeko64" ||
2269 Name == "\1ftello64") {
2270 if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
2273 setDoesNotCapture(F, 1);
2274 } else if (Name == "\1tmpfile64") {
2275 if (!FTy->getReturnType()->isPointerTy())
2278 setDoesNotAlias(F, 0);
2279 } else if (Name == "\1fstat64" ||
2280 Name == "\1fstatvfs64") {
2281 if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
2284 setDoesNotCapture(F, 2);
2285 } else if (Name == "\1open64") {
2286 if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
2288 // May throw; "open" is a valid pthread cancellation point.
2289 setDoesNotCapture(F, 1);
2295 /// doInitialization - Add attributes to well-known functions.
2297 bool SimplifyLibCalls::doInitialization(Module &M) {
2299 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
2301 if (F.isDeclaration() && F.hasName())
2302 inferPrototypeAttributes(F);
2308 // Additional cases that we need to add to this file:
2311 // * cbrt(expN(X)) -> expN(x/3)
2312 // * cbrt(sqrt(x)) -> pow(x,1/6)
2313 // * cbrt(sqrt(x)) -> pow(x,1/9)
2316 // * exp(log(x)) -> x
2319 // * log(exp(x)) -> x
2320 // * log(x**y) -> y*log(x)
2321 // * log(exp(y)) -> y*log(e)
2322 // * log(exp2(y)) -> y*log(2)
2323 // * log(exp10(y)) -> y*log(10)
2324 // * log(sqrt(x)) -> 0.5*log(x)
2325 // * log(pow(x,y)) -> y*log(x)
2327 // lround, lroundf, lroundl:
2328 // * lround(cnst) -> cnst'
2331 // * pow(exp(x),y) -> exp(x*y)
2332 // * pow(sqrt(x),y) -> pow(x,y*0.5)
2333 // * pow(pow(x,y),z)-> pow(x,y*z)
2335 // round, roundf, roundl:
2336 // * round(cnst) -> cnst'
2339 // * signbit(cnst) -> cnst'
2340 // * signbit(nncst) -> 0 (if pstv is a non-negative constant)
2342 // sqrt, sqrtf, sqrtl:
2343 // * sqrt(expN(x)) -> expN(x*0.5)
2344 // * sqrt(Nroot(x)) -> pow(x,1/(2*N))
2345 // * sqrt(pow(x,y)) -> pow(|x|,y*0.5)
2348 // * strchr(p, 0) -> strlen(p)
2350 // * tan(atan(x)) -> x
2352 // trunc, truncf, truncl:
2353 // * trunc(cnst) -> cnst'