stpcpy is so similar to strcpy, it doesn't deserve a complete copy of the __strcpy_chk -> strcpy code.

llvm-svn: 98284

3 files changed, 11 insertions, 58 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 43ff58d8ff1..4b933f08b13 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -819,36 +819,19 @@ Instruction *InstCombiner::tryOptimizeCall(CallInst *CI, const TargetData *TD) {
     return 0;
   }
 
-  if (Name == "__strcpy_chk") {
+  if (Name == "__strcpy_chk" || Name == "__stpcpy_chk") {
     ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(3));
     if (!SizeCI)
       return 0;
     // If a) we don't have any length information, or b) we know this will
-    // fit then just lower to a plain strcpy. Otherwise we'll keep our
-    // strcpy_chk call which may fail at runtime if the size is too long.
+    // fit then just lower to a plain st[rp]cpy. Otherwise we'll keep our
+    // st[rp]cpy_chk call which may fail at runtime if the size is too long.
     // TODO: It might be nice to get a maximum length out of the possible
     // string lengths for varying.
     if (SizeCI->isAllOnesValue() ||
       SizeCI->getZExtValue() >= GetStringLength(CI->getOperand(2))) {
-      Value *Ret = EmitStrCpy(CI->getOperand(1), CI->getOperand(2), B, TD);
-      return ReplaceInstUsesWith(*CI, Ret);
-    }
-    return 0;
-  }
-
-  // Should be similar to strcpy.
-  if (Name == "__stpcpy_chk") {
-    ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(3));
-    if (!SizeCI)
-      return 0;
-    // If a) we don't have any length information, or b) we know this will
-    // fit then just lower to a plain stpcpy. Otherwise we'll keep our
-    // stpcpy_chk call which may fail at runtime if the size is too long.
-    // TODO: It might be nice to get a maximum length out of the possible
-    // string lengths for varying.
-    if (SizeCI->isAllOnesValue() ||
-        SizeCI->getZExtValue() >= GetStringLength(CI->getOperand(2))) {
-      Value *Ret = EmitStpCpy(CI->getOperand(1), CI->getOperand(2), B, TD);
+      Value *Ret = EmitStrCpy(CI->getOperand(1), CI->getOperand(2), B, TD,
+                              Name.substr(2, 6));
       return ReplaceInstUsesWith(*CI, Ret);
     }
     return 0;
diff --git a/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp b/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp
index c428d2b0b0c..c26d74d0857 100644
--- a/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp
+++ b/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp
@@ -620,25 +620,13 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
     return 0;
   }
 
-  if (Name == "__strcpy_chk") {
+  if (Name == "__strcpy_chk" || Name == "__stpcpy_chk") {
     ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(3));
     if (!SizeCI)
       return 0;
     if (SizeCI->isAllOnesValue()) {
-      Value *Ret = EmitStrCpy(CI->getOperand(1), CI->getOperand(2), B, TD);
-      CI->replaceAllUsesWith(Ret);
-      CI->eraseFromParent();
-      return true;
-    }
-    return 0;
-  }
-
-  if (Name == "__stpcpy_chk") {
-    ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(3));
-    if (!SizeCI)
-      return 0;
-    if (SizeCI->isAllOnesValue()) {
-      Value *Ret = EmitStpCpy(CI->getOperand(1), CI->getOperand(2), B, TD);
+      Value *Ret = EmitStrCpy(CI->getOperand(1), CI->getOperand(2), B, TD,
+                              Name.substr(2, 6));
       CI->replaceAllUsesWith(Ret);
       CI->eraseFromParent();
       return true;
diff --git a/llvm/lib/Transforms/Utils/BuildLibCalls.cpp b/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
index 7f62166f2e2..a4776343606 100644
--- a/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
+++ b/llvm/lib/Transforms/Utils/BuildLibCalls.cpp
@@ -72,39 +72,21 @@ Value *llvm::EmitStrChr(Value *Ptr, char C, IRBuilder<> &B,
 /// EmitStrCpy - Emit a call to the strcpy function to the builder, for the
 /// specified pointer arguments.
 Value *llvm::EmitStrCpy(Value *Dst, Value *Src, IRBuilder<> &B,
-                        const TargetData *TD) {
+                        const TargetData *TD, StringRef Name) {
   Module *M = B.GetInsertBlock()->getParent()->getParent();
   AttributeWithIndex AWI[2];
   AWI[0] = AttributeWithIndex::get(2, Attribute::NoCapture);
   AWI[1] = AttributeWithIndex::get(~0u, Attribute::NoUnwind);
   const Type *I8Ptr = B.getInt8PtrTy();
-  Value *StrCpy = M->getOrInsertFunction("strcpy", AttrListPtr::get(AWI, 2),
+  Value *StrCpy = M->getOrInsertFunction(Name, AttrListPtr::get(AWI, 2),
                                          I8Ptr, I8Ptr, I8Ptr, NULL);
   CallInst *CI = B.CreateCall2(StrCpy, CastToCStr(Dst, B), CastToCStr(Src, B),
-                               "strcpy");
+                               Name);
   if (const Function *F = dyn_cast<Function>(StrCpy->stripPointerCasts()))
     CI->setCallingConv(F->getCallingConv());
   return CI;
 }
 
-/// EmitStpCpy - Emit a call to the stpcpy function to the builder, for the
-/// specified pointer arguments.
-Value *llvm::EmitStpCpy(Value *Dst, Value *Src, IRBuilder<> &B,
-                        const TargetData *TD) {
-  Module *M = B.GetInsertBlock()->getParent()->getParent();
-  AttributeWithIndex AWI[2];
-  AWI[0] = AttributeWithIndex::get(2, Attribute::NoCapture);
-  AWI[1] = AttributeWithIndex::get(~0u, Attribute::NoUnwind);
-  const Type *I8Ptr = B.getInt8PtrTy();
-  Value *StpCpy = M->getOrInsertFunction("stpcpy", AttrListPtr::get(AWI, 2),
-                                         I8Ptr, I8Ptr, I8Ptr, NULL);
-  CallInst *CI = B.CreateCall2(StpCpy, CastToCStr(Dst, B), CastToCStr(Src, B),
-                               "stpcpy");
-  if (const Function *F = dyn_cast<Function>(StpCpy->stripPointerCasts()))
-    CI->setCallingConv(F->getCallingConv());
-  return CI;
-}
-
 /// EmitStrNCpy - Emit a call to the strncpy function to the builder, for the
 /// specified pointer arguments.
 Value *llvm::EmitStrNCpy(Value *Dst, Value *Src, Value *Len,