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-rw-r--r--lib/Transforms/Scalar/SimplifyLibCalls.cpp49
1 files changed, 42 insertions, 7 deletions
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index 75754a5585..c4787c82f5 100644
--- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -522,6 +522,46 @@ struct StrLenOpt : public LibCallOptimization {
}
};
+
+//===---------------------------------------===//
+// 'strpbrk' Optimizations
+
+struct StrPBrkOpt : public LibCallOptimization {
+ virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ const FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 ||
+ FT->getParamType(0) != Type::getInt8PtrTy(*Context) ||
+ FT->getParamType(1) != FT->getParamType(0) ||
+ FT->getReturnType() != FT->getParamType(0))
+ return 0;
+
+ std::string S1, S2;
+ bool HasS1 = GetConstantStringInfo(CI->getArgOperand(0), S1);
+ bool HasS2 = GetConstantStringInfo(CI->getArgOperand(1), S2);
+
+ // strpbrk(s, "") -> NULL
+ // strpbrk("", s) -> NULL
+ if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
+ return Constant::getNullValue(CI->getType());
+
+ // Constant folding.
+ if (HasS1 && HasS2) {
+ size_t I = S1.find_first_of(S2);
+ if (I == std::string::npos) // No match.
+ return Constant::getNullValue(CI->getType());
+
+ Value *Idx = ConstantInt::get(Type::getInt64Ty(*Context), I);
+ return B.CreateGEP(CI->getArgOperand(0), Idx, "strpbrk");
+ }
+
+ // strpbrk(s, "a") -> strchr(s, 'a')
+ if (TD && HasS2 && S2.size() == 1)
+ return EmitStrChr(CI->getArgOperand(0), S2[0], B, TD);
+
+ return 0;
+ }
+};
+
//===---------------------------------------===//
// 'strto*' Optimizations. This handles strtol, strtod, strtof, strtoul, etc.
@@ -1256,7 +1296,7 @@ namespace {
// 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;
+ StrNCpyOpt StrNCpy; StrLenOpt StrLen; StrPBrkOpt StrPBrk;
StrToOpt StrTo; StrStrOpt StrStr;
MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
// Math Library Optimizations
@@ -1309,6 +1349,7 @@ void SimplifyLibCalls::InitOptimizations() {
Optimizations["strcpy"] = &StrCpy;
Optimizations["strncpy"] = &StrNCpy;
Optimizations["strlen"] = &StrLen;
+ Optimizations["strpbrk"] = &StrPBrk;
Optimizations["strtol"] = &StrTo;
Optimizations["strtod"] = &StrTo;
Optimizations["strtof"] = &StrTo;
@@ -2209,12 +2250,6 @@ bool SimplifyLibCalls::doInitialization(Module &M) {
// * stpcpy(str, "literal") ->
// llvm.memcpy(str,"literal",strlen("literal")+1,1)
//
-// strpbrk:
-// * strpbrk(s,a) -> offset_in_for(s,a)
-// (if s and a are both constant strings)
-// * strpbrk(s,"") -> 0
-// * strpbrk(s,a) -> strchr(s,a[0]) (if a is constant string of length 1)
-//
// strspn, strcspn:
// * strspn(s,a) -> const_int (if both args are constant)
// * strspn("",a) -> 0