Fix isEliminableCastPair to work correctly in the presence of pointers
with different sizes.

llvm-svn: 167018
diff --git a/llvm/lib/VMCore/Instructions.cpp b/llvm/lib/VMCore/Instructions.cpp
index e9b96d6..39ba4df 100644
--- a/llvm/lib/VMCore/Instructions.cpp
+++ b/llvm/lib/VMCore/Instructions.cpp
@@ -2141,7 +2141,8 @@
 /// If no such cast is permited, the function returns 0.
 unsigned CastInst::isEliminableCastPair(
   Instruction::CastOps firstOp, Instruction::CastOps secondOp,
-  Type *SrcTy, Type *MidTy, Type *DstTy, Type *IntPtrTy) {
+  Type *SrcTy, Type *MidTy, Type *DstTy, Type *SrcIntPtrTy, Type *MidIntPtrTy,
+  Type *DstIntPtrTy) {
   // Define the 144 possibilities for these two cast instructions. The values
   // in this matrix determine what to do in a given situation and select the
   // case in the switch below.  The rows correspond to firstOp, the columns 
@@ -2244,9 +2245,9 @@
       return 0;
     case 7: { 
       // ptrtoint, inttoptr -> bitcast (ptr -> ptr) if int size is >= ptr size
-      if (!IntPtrTy)
+      if (!SrcIntPtrTy || DstIntPtrTy != SrcIntPtrTy)
         return 0;
-      unsigned PtrSize = IntPtrTy->getScalarSizeInBits();
+      unsigned PtrSize = SrcIntPtrTy->getScalarSizeInBits();
       unsigned MidSize = MidTy->getScalarSizeInBits();
       if (MidSize >= PtrSize)
         return Instruction::BitCast;
@@ -2285,9 +2286,9 @@
       return 0;
     case 13: {
       // inttoptr, ptrtoint -> bitcast if SrcSize<=PtrSize and SrcSize==DstSize
-      if (!IntPtrTy)
+      if (!MidIntPtrTy)
         return 0;
-      unsigned PtrSize = IntPtrTy->getScalarSizeInBits();
+      unsigned PtrSize = MidIntPtrTy->getScalarSizeInBits();
       unsigned SrcSize = SrcTy->getScalarSizeInBits();
       unsigned DstSize = DstTy->getScalarSizeInBits();
       if (SrcSize <= PtrSize && SrcSize == DstSize)