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-rw-r--r--lib/Transforms/Scalar/SimplifyLibCalls.cpp61
-rw-r--r--test/Transforms/SimplifyLibCalls/StpCpy.ll43
2 files changed, 97 insertions, 7 deletions
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index f7b6941..99b0538 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 0000000..738db37
--- /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
+}