[llvm-commits] CVS: llvm/lib/Transforms/IPO/SimplifyLibCalls.cpp

[Reid Spencer]

Changes in directory llvm/lib/Transforms/IPO:

SimplifyLibCalls.cpp updated: 1.42 -> 1.43
---
Log message:

Fix a problem with the strcmp optimization checking the wrong string and
not casting to the correct type. 


---
Diffs of the changes:  (+16 -13)

 SimplifyLibCalls.cpp |   29 ++++++++++++++++-------------
 1 files changed, 16 insertions(+), 13 deletions(-)


Index: llvm/lib/Transforms/IPO/SimplifyLibCalls.cpp
diff -u llvm/lib/Transforms/IPO/SimplifyLibCalls.cpp:1.42 llvm/lib/Transforms/IPO/SimplifyLibCalls.cpp:1.43
--- llvm/lib/Transforms/IPO/SimplifyLibCalls.cpp:1.42	Fri May 20 20:27:04 2005
+++ llvm/lib/Transforms/IPO/SimplifyLibCalls.cpp	Sat Jun 18 12:46:28 2005
@@ -367,8 +367,9 @@
 // auto registers it into the "optlist" global above. 
 namespace {
 
-// Forward declare a utility function.
+// Forward declare utility functions.
 bool getConstantStringLength(Value* V, uint64_t& len, ConstantArray** A = 0 );
+Value *CastToCStr(Value *V, Instruction &IP);
 
 /// This LibCallOptimization will find instances of a call to "exit" that occurs
 /// within the "main" function and change it to a simple "ret" instruction with
@@ -663,7 +664,8 @@
       if (len_1 == 0)
       {
         // strcmp("",x) -> *x
-        LoadInst* load = new LoadInst(s1,ci->getName()+".load",ci);
+        LoadInst* load = 
+          new LoadInst(CastToCStr(s2,*ci), ci->getName()+".load",ci);
         CastInst* cast = 
           new CastInst(load,Type::IntTy,ci->getName()+".int",ci);
         ci->replaceAllUsesWith(cast);
@@ -681,7 +683,8 @@
       if (len_2 == 0)
       {
         // strcmp(x,"") -> *x
-        LoadInst* load = new LoadInst(s2,ci->getName()+".val",ci);
+        LoadInst* load = 
+          new LoadInst(CastToCStr(s1,*ci),ci->getName()+".val",ci);
         CastInst* cast = 
           new CastInst(load,Type::IntTy,ci->getName()+".int",ci);
         ci->replaceAllUsesWith(cast);
@@ -1242,16 +1245,6 @@
   }
 } PowOptimizer;
 
-/// CastToCStr - Return V if it is an sbyte*, otherwise cast it to sbyte*,
-/// inserting the cast before IP, and return the cast.
-/// @brief Cast a value to a "C" string.
-static Value *CastToCStr(Value *V, Instruction &IP) {
-  const Type *SBPTy = PointerType::get(Type::SByteTy);
-  if (V->getType() != SBPTy)
-    return new CastInst(V, SBPTy, V->getName(), &IP);
-  return V;
-}
-
 /// This LibCallOptimization will simplify calls to the "fprintf" library 
 /// function. It looks for cases where the result of fprintf is not used and the
 /// operation can be reduced to something simpler.
@@ -1889,6 +1882,16 @@
   return true; // success!
 }
 
+/// CastToCStr - Return V if it is an sbyte*, otherwise cast it to sbyte*,
+/// inserting the cast before IP, and return the cast.
+/// @brief Cast a value to a "C" string.
+Value *CastToCStr(Value *V, Instruction &IP) {
+  const Type *SBPTy = PointerType::get(Type::SByteTy);
+  if (V->getType() != SBPTy)
+    return new CastInst(V, SBPTy, V->getName(), &IP);
+  return V;
+}
+
 // TODO: 
 //   Additional cases that we need to add to this file:
 //