instcombine: Migrate stpcpy optimizations
This patch migrates the stpcpy optimizations from the simplify-libcalls
pass into the instcombine library call simplifier. Note that the
__stpcpy_chk simplifications were migrated in a previous commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167083 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index f3448bc..f7593e7 100644
--- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -135,52 +135,6 @@
namespace {
//===---------------------------------------===//
-// '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 DataLayout.
- 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;
-
- Type *PT = FT->getParamType(0);
- Value *LenV = ConstantInt::get(TD->getIntPtrType(PT), Len);
- Value *DstEnd = B.CreateGEP(Dst,
- ConstantInt::get(TD->getIntPtrType(PT),
- 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 {
@@ -1242,7 +1196,6 @@
StringMap<LibCallOptimization*> Optimizations;
// String and Memory LibCall Optimizations
- StpCpyOpt StpCpy; StpCpyOpt StpCpyChk;
StrNCpyOpt StrNCpy;
StrLenOpt StrLen; StrPBrkOpt StrPBrk;
StrToOpt StrTo; StrSpnOpt StrSpn; StrCSpnOpt StrCSpn; StrStrOpt StrStr;
@@ -1261,8 +1214,8 @@
bool Modified; // This is only used by doInitialization.
public:
static char ID; // Pass identification
- SimplifyLibCalls() : FunctionPass(ID), StpCpy(false), StpCpyChk(true),
- UnaryDoubleFP(false), UnsafeUnaryDoubleFP(true) {
+ SimplifyLibCalls() : FunctionPass(ID), UnaryDoubleFP(false),
+ UnsafeUnaryDoubleFP(true) {
initializeSimplifyLibCallsPass(*PassRegistry::getPassRegistry());
}
void AddOpt(LibFunc::Func F, LibCallOptimization* Opt);
@@ -1314,7 +1267,6 @@
void SimplifyLibCalls::InitOptimizations() {
// String and Memory LibCall Optimizations
Optimizations["strncpy"] = &StrNCpy;
- Optimizations["stpcpy"] = &StpCpy;
Optimizations["strlen"] = &StrLen;
Optimizations["strpbrk"] = &StrPBrk;
Optimizations["strtol"] = &StrTo;
@@ -1332,9 +1284,6 @@
Optimizations["memmove"] = &MemMove;
AddOpt(LibFunc::memset, &MemSet);
- // _chk variants of String and Memory LibCall Optimizations.
- Optimizations["__stpcpy_chk"] = &StpCpyChk;
-
// Math Library Optimizations
Optimizations["cosf"] = &Cos;
Optimizations["cos"] = &Cos;
diff --git a/lib/Transforms/Utils/SimplifyLibCalls.cpp b/lib/Transforms/Utils/SimplifyLibCalls.cpp
index 5984a96..bc36001 100644
--- a/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -592,6 +592,42 @@
}
};
+struct StpCpyOpt: public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Verify the "stpcpy" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 ||
+ FT->getReturnType() != FT->getParamType(0) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != B.getInt8PtrTy())
+ return 0;
+
+ // These optimizations require DataLayout.
+ 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;
+
+ Type *PT = FT->getParamType(0);
+ Value *LenV = ConstantInt::get(TD->getIntPtrType(PT), Len);
+ Value *DstEnd = B.CreateGEP(Dst,
+ ConstantInt::get(TD->getIntPtrType(PT),
+ 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.
+ B.CreateMemCpy(Dst, Src, LenV, 1);
+ return DstEnd;
+ }
+};
+
} // End anonymous namespace.
namespace llvm {
@@ -617,6 +653,7 @@
StrCmpOpt StrCmp;
StrNCmpOpt StrNCmp;
StrCpyOpt StrCpy;
+ StpCpyOpt StpCpy;
void initOptimizations();
public:
@@ -646,6 +683,7 @@
Optimizations["strcmp"] = &StrCmp;
Optimizations["strncmp"] = &StrNCmp;
Optimizations["strcpy"] = &StrCpy;
+ Optimizations["stpcpy"] = &StpCpy;
}
Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {