diff options
| -rw-r--r-- | lib/Transforms/Scalar/SimplifyLibCalls.cpp | 61 | ||||
| -rw-r--r-- | test/Transforms/SimplifyLibCalls/StpCpy.ll | 43 |
2 files changed, 97 insertions, 7 deletions
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp index f7b69411b1..99b05389b2 100644 --- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp +++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp @@ -459,6 +459,50 @@ 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) + return B.CreateInBoundsGEP(Dst, EmitStrLen(Src, B, TD)); + + // 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); + else + B.CreateMemCpy(Dst, Src, LenV, 1); + return DstEnd; + } +}; + +//===---------------------------------------===// // 'strncpy' Optimizations struct StrNCpyOpt : public LibCallOptimization { @@ -1474,8 +1518,11 @@ namespace { 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 @@ -1491,7 +1538,8 @@ namespace { 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 +1590,7 @@ 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 +1610,7 @@ 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; @@ -1746,6 +1796,7 @@ 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 +2457,6 @@ 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: diff --git a/test/Transforms/SimplifyLibCalls/StpCpy.ll b/test/Transforms/SimplifyLibCalls/StpCpy.ll new file mode 100644 index 0000000000..738db373a5 --- /dev/null +++ b/test/Transforms/SimplifyLibCalls/StpCpy.ll @@ -0,0 +1,43 @@ +; Test that the StpCpyOptimizer works correctly +; RUN: opt < %s -simplify-libcalls -S | FileCheck %s + +; This transformation requires the pointer size, as it assumes that size_t is +; the size of a pointer. +target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32" + +@hello = constant [6 x i8] c"hello\00" + +declare i8* @stpcpy(i8*, i8*) + +declare i8* @__stpcpy_chk(i8*, i8*, i32) nounwind + +declare i32 @llvm.objectsize.i32(i8*, i1, i32) nounwind readonly + +define i32 @t1() { +; CHECK: @t1 + %target = alloca [1024 x i8] + %arg1 = getelementptr [1024 x i8]* %target, i32 0, i32 0 + %arg2 = getelementptr [6 x i8]* @hello, i32 0, i32 0 + %rslt1 = call i8* @stpcpy( i8* %arg1, i8* %arg2 ) +; CHECK: @llvm.memcpy.p0i8.p0i8.i32 + ret i32 0 +} + +define i32 @t2() { +; CHECK: @t2 + %target = alloca [1024 x i8] + %arg1 = getelementptr [1024 x i8]* %target, i32 0, i32 0 + %arg2 = getelementptr [6 x i8]* @hello, i32 0, i32 0 + %tmp1 = call i32 @llvm.objectsize.i32(i8* %arg1, i1 false, i32 0) + %rslt1 = call i8* @__stpcpy_chk(i8* %arg1, i8* %arg2, i32 %tmp1) +; CHECK: @__memcpy_chk + ret i32 0 +} + +define i8* @t3(i8* %arg) { +; CHECK: @t3 + %stpcpy = tail call i8* @stpcpy(i8* %arg, i8* %arg) +; CHECK: [[LEN:%[a-z]+]] = call i32 @strlen(i8* %arg) +; CHECK-NEXT: getelementptr inbounds i8* %arg, i32 [[LEN]] + ret i8* %stpcpy +} |