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-rw-r--r--lib/Transforms/Scalar/SimplifyLibCalls.cpp83
1 files changed, 65 insertions, 18 deletions
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index f7b6941..a1a8a41 100644
--- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -18,20 +18,20 @@
#define DEBUG_TYPE "simplify-libcalls"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
+#include "llvm/IRBuilder.h"
#include "llvm/Intrinsics.h"
#include "llvm/LLVMContext.h"
#include "llvm/Module.h"
#include "llvm/Pass.h"
-#include "llvm/Support/IRBuilder.h"
-#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/Target/TargetData.h"
-#include "llvm/Target/TargetLibraryInfo.h"
+#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/Config/config.h" // FIXME: Shouldn't depend on host!
using namespace llvm;
@@ -100,7 +100,7 @@ static bool IsOnlyUsedInZeroEqualityComparison(Value *V) {
}
return true;
}
-
+
static bool CallHasFloatingPointArgument(const CallInst *CI) {
for (CallInst::const_op_iterator it = CI->op_begin(), e = CI->op_end();
it != e; ++it) {
@@ -256,7 +256,7 @@ struct StrChrOpt : public LibCallOptimization {
ConstantInt::get(TD->getIntPtrType(*Context), Len),
B, TD);
}
-
+
// Otherwise, the character is a constant, see if the first argument is
// a string literal. If so, we can constant fold.
StringRef Str;
@@ -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 {
@@ -1470,12 +1514,15 @@ namespace {
///
class SimplifyLibCalls : public FunctionPass {
TargetLibraryInfo *TLI;
-
+
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
@@ -1487,11 +1534,12 @@ namespace {
SPrintFOpt SPrintF; PrintFOpt PrintF;
FWriteOpt FWrite; FPutsOpt FPuts; FPrintFOpt FPrintF;
PutsOpt Puts;
-
+
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;
@@ -1717,7 +1767,7 @@ void SimplifyLibCalls::setDoesNotAlias(Function &F, unsigned n) {
void SimplifyLibCalls::inferPrototypeAttributes(Function &F) {
FunctionType *FTy = F.getFunctionType();
-
+
StringRef Name = F.getName();
switch (Name[0]) {
case 's':
@@ -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:
generated by cgit v1.1 at 2025-08-15 14:50:47 +0000