instcombine: Migrate strcspn optimizations
This patch migrates the strcspn optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167675 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index 7d652de..370b818 100644
--- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -119,41 +119,6 @@
namespace {
//===---------------------------------------===//
-// 'strcspn' Optimizations
-
-struct StrCSpnOpt : public LibCallOptimization {
- virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- FT->getParamType(0) != B.getInt8PtrTy() ||
- FT->getParamType(1) != FT->getParamType(0) ||
- !FT->getReturnType()->isIntegerTy())
- return 0;
-
- StringRef S1, S2;
- bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
- bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
-
- // strcspn("", s) -> 0
- if (HasS1 && S1.empty())
- return Constant::getNullValue(CI->getType());
-
- // Constant folding.
- if (HasS1 && HasS2) {
- size_t Pos = S1.find_first_of(S2);
- if (Pos == StringRef::npos) Pos = S1.size();
- return ConstantInt::get(CI->getType(), Pos);
- }
-
- // strcspn(s, "") -> strlen(s)
- if (TD && HasS2 && S2.empty())
- return EmitStrLen(CI->getArgOperand(0), B, TD, TLI);
-
- return 0;
- }
-};
-
-//===---------------------------------------===//
// 'strstr' Optimizations
struct StrStrOpt : public LibCallOptimization {
@@ -1005,7 +970,7 @@
StringMap<LibCallOptimization*> Optimizations;
// String and Memory LibCall Optimizations
- StrCSpnOpt StrCSpn; StrStrOpt StrStr;
+ StrStrOpt StrStr;
MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
// Math Library Optimizations
CosOpt Cos; PowOpt Pow; Exp2Opt Exp2;
@@ -1073,7 +1038,6 @@
/// we know.
void SimplifyLibCalls::InitOptimizations() {
// String and Memory LibCall Optimizations
- Optimizations["strcspn"] = &StrCSpn;
Optimizations["strstr"] = &StrStr;
Optimizations["memcmp"] = &MemCmp;
AddOpt(LibFunc::memcpy, &MemCpy);