diff options
Diffstat (limited to 'lib/Transforms/Scalar/SimplifyLibCalls.cpp')
| -rw-r--r-- | lib/Transforms/Scalar/SimplifyLibCalls.cpp | 189 |
1 files changed, 122 insertions, 67 deletions
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp index f7b69411b1d3..f110320c1bf9 100644 --- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp +++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp @@ -18,20 +18,20 @@ #define DEBUG_TYPE "simplify-libcalls" #include "llvm/Transforms/Scalar.h" #include "llvm/Transforms/Utils/BuildLibCalls.h" +#include "llvm/IRBuilder.h" #include "llvm/Intrinsics.h" #include "llvm/LLVMContext.h" #include "llvm/Module.h" #include "llvm/Pass.h" -#include "llvm/Support/IRBuilder.h" -#include "llvm/Analysis/ValueTracking.h" -#include "llvm/Target/TargetData.h" -#include "llvm/Target/TargetLibraryInfo.h" +#include "llvm/ADT/STLExtras.h" #include "llvm/ADT/SmallPtrSet.h" -#include "llvm/ADT/StringMap.h" #include "llvm/ADT/Statistic.h" -#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/StringMap.h" +#include "llvm/Analysis/ValueTracking.h" #include "llvm/Support/Debug.h" #include "llvm/Support/raw_ostream.h" +#include "llvm/Target/TargetData.h" +#include "llvm/Target/TargetLibraryInfo.h" #include "llvm/Config/config.h" // FIXME: Shouldn't depend on host! using namespace llvm; @@ -100,7 +100,7 @@ static bool IsOnlyUsedInZeroEqualityComparison(Value *V) { } return true; } - + static bool CallHasFloatingPointArgument(const CallInst *CI) { for (CallInst::const_op_iterator it = CI->op_begin(), e = CI->op_end(); it != e; ++it) { @@ -157,14 +157,15 @@ struct StrCatOpt : public LibCallOptimization { // These optimizations require TargetData. if (!TD) return 0; - EmitStrLenMemCpy(Src, Dst, Len, B); - return Dst; + return EmitStrLenMemCpy(Src, Dst, Len, B); } - void EmitStrLenMemCpy(Value *Src, Value *Dst, uint64_t Len, IRBuilder<> &B) { + Value *EmitStrLenMemCpy(Value *Src, Value *Dst, uint64_t Len, IRBuilder<> &B) { // We need to find the end of the destination string. That's where the // memory is to be moved to. We just generate a call to strlen. - Value *DstLen = EmitStrLen(Dst, B, TD); + Value *DstLen = EmitStrLen(Dst, B, TD, TLI); + if (!DstLen) + return 0; // Now that we have the destination's length, we must index into the // destination's pointer to get the actual memcpy destination (end of @@ -175,6 +176,7 @@ struct StrCatOpt : public LibCallOptimization { // concatenation for us. Make a memcpy to copy the nul byte with align = 1. B.CreateMemCpy(CpyDst, Src, ConstantInt::get(TD->getIntPtrType(*Context), Len + 1), 1); + return Dst; } }; @@ -221,8 +223,7 @@ struct StrNCatOpt : public StrCatOpt { // strncat(x, s, c) -> strcat(x, s) // s is constant so the strcat can be optimized further - EmitStrLenMemCpy(Src, Dst, SrcLen, B); - return Dst; + return EmitStrLenMemCpy(Src, Dst, SrcLen, B); } }; @@ -254,9 +255,9 @@ struct StrChrOpt : public LibCallOptimization { return EmitMemChr(SrcStr, CI->getArgOperand(1), // include nul. ConstantInt::get(TD->getIntPtrType(*Context), Len), - B, TD); + B, TD, TLI); } - + // Otherwise, the character is a constant, see if the first argument is // a string literal. If so, we can constant fold. StringRef Str; @@ -299,7 +300,7 @@ struct StrRChrOpt : public LibCallOptimization { if (!getConstantStringInfo(SrcStr, Str)) { // strrchr(s, 0) -> strchr(s, 0) if (TD && CharC->isZero()) - return EmitStrChr(SrcStr, '\0', B, TD); + return EmitStrChr(SrcStr, '\0', B, TD, TLI); return 0; } @@ -355,7 +356,7 @@ struct StrCmpOpt : public LibCallOptimization { return EmitMemCmp(Str1P, Str2P, ConstantInt::get(TD->getIntPtrType(*Context), - std::min(Len1, Len2)), B, TD); + std::min(Len1, Len2)), B, TD, TLI); } return 0; @@ -391,7 +392,7 @@ struct StrNCmpOpt : public LibCallOptimization { return ConstantInt::get(CI->getType(), 0); if (TD && Length == 1) // strncmp(x,y,1) -> memcmp(x,y,1) - return EmitMemCmp(Str1P, Str2P, CI->getArgOperand(2), B, TD); + return EmitMemCmp(Str1P, Str2P, CI->getArgOperand(2), B, TD, TLI); StringRef Str1, Str2; bool HasStr1 = getConstantStringInfo(Str1P, Str1); @@ -447,11 +448,10 @@ struct StrCpyOpt : public LibCallOptimization { // We have enough information to now generate the memcpy call to do the // concatenation for us. Make a memcpy to copy the nul byte with align = 1. - if (OptChkCall) - EmitMemCpyChk(Dst, Src, - ConstantInt::get(TD->getIntPtrType(*Context), Len), - CI->getArgOperand(2), B, TD); - else + if (!OptChkCall || + !EmitMemCpyChk(Dst, Src, + ConstantInt::get(TD->getIntPtrType(*Context), Len), + CI->getArgOperand(2), B, TD, TLI)) B.CreateMemCpy(Dst, Src, ConstantInt::get(TD->getIntPtrType(*Context), Len), 1); return Dst; @@ -459,6 +459,51 @@ struct StrCpyOpt : public LibCallOptimization { }; //===---------------------------------------===// +// 'stpcpy' Optimizations + +struct StpCpyOpt: public LibCallOptimization { + bool OptChkCall; // True if it's optimizing a __stpcpy_chk libcall. + + StpCpyOpt(bool c) : OptChkCall(c) {} + + virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) { + // Verify the "stpcpy" function prototype. + unsigned NumParams = OptChkCall ? 3 : 2; + FunctionType *FT = Callee->getFunctionType(); + if (FT->getNumParams() != NumParams || + FT->getReturnType() != FT->getParamType(0) || + FT->getParamType(0) != FT->getParamType(1) || + FT->getParamType(0) != B.getInt8PtrTy()) + return 0; + + // These optimizations require TargetData. + if (!TD) return 0; + + Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1); + if (Dst == Src) { // stpcpy(x,x) -> x+strlen(x) + Value *StrLen = EmitStrLen(Src, B, TD, TLI); + return StrLen ? B.CreateInBoundsGEP(Dst, StrLen) : 0; + } + + // See if we can get the length of the input string. + uint64_t Len = GetStringLength(Src); + if (Len == 0) return 0; + + Value *LenV = ConstantInt::get(TD->getIntPtrType(*Context), Len); + Value *DstEnd = B.CreateGEP(Dst, + ConstantInt::get(TD->getIntPtrType(*Context), + Len - 1)); + + // We have enough information to now generate the memcpy call to do the + // copy for us. Make a memcpy to copy the nul byte with align = 1. + if (!OptChkCall || !EmitMemCpyChk(Dst, Src, LenV, CI->getArgOperand(2), B, + TD, TLI)) + B.CreateMemCpy(Dst, Src, LenV, 1); + return DstEnd; + } +}; + +//===---------------------------------------===// // 'strncpy' Optimizations struct StrNCpyOpt : public LibCallOptimization { @@ -565,7 +610,7 @@ struct StrPBrkOpt : public LibCallOptimization { // strpbrk(s, "a") -> strchr(s, 'a') if (TD && HasS2 && S2.size() == 1) - return EmitStrChr(CI->getArgOperand(0), S2[0], B, TD); + return EmitStrChr(CI->getArgOperand(0), S2[0], B, TD, TLI); return 0; } @@ -654,7 +699,7 @@ struct StrCSpnOpt : public LibCallOptimization { // strcspn(s, "") -> strlen(s) if (TD && HasS2 && S2.empty()) - return EmitStrLen(CI->getArgOperand(0), B, TD); + return EmitStrLen(CI->getArgOperand(0), B, TD, TLI); return 0; } @@ -678,9 +723,13 @@ struct StrStrOpt : public LibCallOptimization { // fold strstr(a, b) == a -> strncmp(a, b, strlen(b)) == 0 if (TD && IsOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) { - Value *StrLen = EmitStrLen(CI->getArgOperand(1), B, TD); + Value *StrLen = EmitStrLen(CI->getArgOperand(1), B, TD, TLI); + if (!StrLen) + return 0; Value *StrNCmp = EmitStrNCmp(CI->getArgOperand(0), CI->getArgOperand(1), - StrLen, B, TD); + StrLen, B, TD, TLI); + if (!StrNCmp) + return 0; for (Value::use_iterator UI = CI->use_begin(), UE = CI->use_end(); UI != UE; ) { ICmpInst *Old = cast<ICmpInst>(*UI++); @@ -716,9 +765,10 @@ struct StrStrOpt : public LibCallOptimization { } // fold strstr(x, "y") -> strchr(x, 'y'). - if (HasStr2 && ToFindStr.size() == 1) - return B.CreateBitCast(EmitStrChr(CI->getArgOperand(0), - ToFindStr[0], B, TD), CI->getType()); + if (HasStr2 && ToFindStr.size() == 1) { + Value *StrChr= EmitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TD, TLI); + return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : 0; + } return 0; } }; @@ -1135,8 +1185,8 @@ struct PrintFOpt : public LibCallOptimization { // printf("x") -> putchar('x'), even for '%'. if (FormatStr.size() == 1) { - Value *Res = EmitPutChar(B.getInt32(FormatStr[0]), B, TD); - if (CI->use_empty()) return CI; + Value *Res = EmitPutChar(B.getInt32(FormatStr[0]), B, TD, TLI); + if (CI->use_empty() || !Res) return Res; return B.CreateIntCast(Res, CI->getType(), true); } @@ -1147,26 +1197,26 @@ struct PrintFOpt : public LibCallOptimization { // pass to be run after this pass, to merge duplicate strings. FormatStr = FormatStr.drop_back(); Value *GV = B.CreateGlobalString(FormatStr, "str"); - EmitPutS(GV, B, TD); - return CI->use_empty() ? (Value*)CI : - ConstantInt::get(CI->getType(), FormatStr.size()+1); + Value *NewCI = EmitPutS(GV, B, TD, TLI); + return (CI->use_empty() || !NewCI) ? + NewCI : + ConstantInt::get(CI->getType(), FormatStr.size()+1); } // Optimize specific format strings. // printf("%c", chr) --> putchar(chr) if (FormatStr == "%c" && CI->getNumArgOperands() > 1 && CI->getArgOperand(1)->getType()->isIntegerTy()) { - Value *Res = EmitPutChar(CI->getArgOperand(1), B, TD); + Value *Res = EmitPutChar(CI->getArgOperand(1), B, TD, TLI); - if (CI->use_empty()) return CI; + if (CI->use_empty() || !Res) return Res; return B.CreateIntCast(Res, CI->getType(), true); } // printf("%s\n", str) --> puts(str) if (FormatStr == "%s\n" && CI->getNumArgOperands() > 1 && CI->getArgOperand(1)->getType()->isPointerTy()) { - EmitPutS(CI->getArgOperand(1), B, TD); - return CI; + return EmitPutS(CI->getArgOperand(1), B, TD, TLI); } return 0; } @@ -1253,7 +1303,9 @@ struct SPrintFOpt : public LibCallOptimization { // sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1) if (!CI->getArgOperand(2)->getType()->isPointerTy()) return 0; - Value *Len = EmitStrLen(CI->getArgOperand(2), B, TD); + Value *Len = EmitStrLen(CI->getArgOperand(2), B, TD, TLI); + if (!Len) + return 0; Value *IncLen = B.CreateAdd(Len, ConstantInt::get(Len->getType(), 1), "leninc"); @@ -1320,8 +1372,8 @@ struct FWriteOpt : public LibCallOptimization { // This optimisation is only valid, if the return value is unused. if (Bytes == 1 && CI->use_empty()) { // fwrite(S,1,1,F) -> fputc(S[0],F) Value *Char = B.CreateLoad(CastToCStr(CI->getArgOperand(0), B), "char"); - EmitFPutC(Char, CI->getArgOperand(3), B, TD); - return ConstantInt::get(CI->getType(), 1); + Value *NewCI = EmitFPutC(Char, CI->getArgOperand(3), B, TD, TLI); + return NewCI ? ConstantInt::get(CI->getType(), 1) : 0; } return 0; @@ -1346,10 +1398,10 @@ struct FPutsOpt : public LibCallOptimization { // fputs(s,F) --> fwrite(s,1,strlen(s),F) uint64_t Len = GetStringLength(CI->getArgOperand(0)); if (!Len) return 0; - EmitFWrite(CI->getArgOperand(0), - ConstantInt::get(TD->getIntPtrType(*Context), Len-1), - CI->getArgOperand(1), B, TD, TLI); - return CI; // Known to have no uses (see above). + // Known to have no uses (see above). + return EmitFWrite(CI->getArgOperand(0), + ConstantInt::get(TD->getIntPtrType(*Context), Len-1), + CI->getArgOperand(1), B, TD, TLI); } }; @@ -1373,11 +1425,11 @@ struct FPrintFOpt : public LibCallOptimization { // These optimizations require TargetData. if (!TD) return 0; - EmitFWrite(CI->getArgOperand(1), - ConstantInt::get(TD->getIntPtrType(*Context), - FormatStr.size()), - CI->getArgOperand(0), B, TD, TLI); - return ConstantInt::get(CI->getType(), FormatStr.size()); + Value *NewCI = EmitFWrite(CI->getArgOperand(1), + ConstantInt::get(TD->getIntPtrType(*Context), + FormatStr.size()), + CI->getArgOperand(0), B, TD, TLI); + return NewCI ? ConstantInt::get(CI->getType(), FormatStr.size()) : 0; } // The remaining optimizations require the format string to be "%s" or "%c" @@ -1390,16 +1442,16 @@ struct FPrintFOpt : public LibCallOptimization { if (FormatStr[1] == 'c') { // fprintf(F, "%c", chr) --> fputc(chr, F) if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0; - EmitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B, TD); - return ConstantInt::get(CI->getType(), 1); + Value *NewCI = EmitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B, + TD, TLI); + return NewCI ? ConstantInt::get(CI->getType(), 1) : 0; } if (FormatStr[1] == 's') { // fprintf(F, "%s", str) --> fputs(str, F) if (!CI->getArgOperand(2)->getType()->isPointerTy() || !CI->use_empty()) return 0; - EmitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TD, TLI); - return CI; + return EmitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TD, TLI); } return 0; } @@ -1450,8 +1502,8 @@ struct PutsOpt : public LibCallOptimization { if (Str.empty() && CI->use_empty()) { // puts("") -> putchar('\n') - Value *Res = EmitPutChar(B.getInt32('\n'), B, TD); - if (CI->use_empty()) return CI; + Value *Res = EmitPutChar(B.getInt32('\n'), B, TD, TLI); + if (CI->use_empty() || !Res) return Res; return B.CreateIntCast(Res, CI->getType(), true); } @@ -1470,12 +1522,15 @@ namespace { /// class SimplifyLibCalls : public FunctionPass { TargetLibraryInfo *TLI; - + StringMap<LibCallOptimization*> Optimizations; // String and Memory LibCall Optimizations StrCatOpt StrCat; StrNCatOpt StrNCat; StrChrOpt StrChr; StrRChrOpt StrRChr; - StrCmpOpt StrCmp; StrNCmpOpt StrNCmp; StrCpyOpt StrCpy; StrCpyOpt StrCpyChk; - StrNCpyOpt StrNCpy; StrLenOpt StrLen; StrPBrkOpt StrPBrk; + StrCmpOpt StrCmp; StrNCmpOpt StrNCmp; + StrCpyOpt StrCpy; StrCpyOpt StrCpyChk; + StpCpyOpt StpCpy; StpCpyOpt StpCpyChk; + StrNCpyOpt StrNCpy; + StrLenOpt StrLen; StrPBrkOpt StrPBrk; StrToOpt StrTo; StrSpnOpt StrSpn; StrCSpnOpt StrCSpn; StrStrOpt StrStr; MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet; // Math Library Optimizations @@ -1487,11 +1542,12 @@ namespace { SPrintFOpt SPrintF; PrintFOpt PrintF; FWriteOpt FWrite; FPutsOpt FPuts; FPrintFOpt FPrintF; PutsOpt Puts; - + bool Modified; // This is only used by doInitialization. public: static char ID; // Pass identification - SimplifyLibCalls() : FunctionPass(ID), StrCpy(false), StrCpyChk(true) { + SimplifyLibCalls() : FunctionPass(ID), StrCpy(false), StrCpyChk(true), + StpCpy(false), StpCpyChk(true) { initializeSimplifyLibCallsPass(*PassRegistry::getPassRegistry()); } void AddOpt(LibFunc::Func F, LibCallOptimization* Opt); @@ -1542,6 +1598,7 @@ void SimplifyLibCalls::InitOptimizations() { Optimizations["strncmp"] = &StrNCmp; Optimizations["strcpy"] = &StrCpy; Optimizations["strncpy"] = &StrNCpy; + Optimizations["stpcpy"] = &StpCpy; Optimizations["strlen"] = &StrLen; Optimizations["strpbrk"] = &StrPBrk; Optimizations["strtol"] = &StrTo; @@ -1561,6 +1618,7 @@ void SimplifyLibCalls::InitOptimizations() { // _chk variants of String and Memory LibCall Optimizations. Optimizations["__strcpy_chk"] = &StrCpyChk; + Optimizations["__stpcpy_chk"] = &StpCpyChk; // Math Library Optimizations Optimizations["cosf"] = &Cos; @@ -1717,7 +1775,7 @@ void SimplifyLibCalls::setDoesNotAlias(Function &F, unsigned n) { void SimplifyLibCalls::inferPrototypeAttributes(Function &F) { FunctionType *FTy = F.getFunctionType(); - + StringRef Name = F.getName(); switch (Name[0]) { case 's': @@ -1746,6 +1804,7 @@ void SimplifyLibCalls::inferPrototypeAttributes(Function &F) { Name == "strtold" || Name == "strncat" || Name == "strncpy" || + Name == "stpncpy" || Name == "strtoull") { if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy()) @@ -2406,10 +2465,6 @@ bool SimplifyLibCalls::doInitialization(Module &M) { // * sqrt(Nroot(x)) -> pow(x,1/(2*N)) // * sqrt(pow(x,y)) -> pow(|x|,y*0.5) // -// stpcpy: -// * stpcpy(str, "literal") -> -// llvm.memcpy(str,"literal",strlen("literal")+1,1) -// // strchr: // * strchr(p, 0) -> strlen(p) // tan, tanf, tanl: |