Don't eliminate bitcast instructions that change the type of a pointer

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48971 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 0 deletions

diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 35715fb8ca..9e069fd05b 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -7575,6 +7575,11 @@ Instruction *InstCombiner::visitBitCast(BitCastInst &CI) {
     const Type *DstElTy = DstPTy->getElementType();
     const Type *SrcElTy = SrcPTy->getElementType();
     
+    // If the address spaces don't match, don't eliminate the bitcast, which is
+    // required for changing types.
+    if (SrcPTy->getAddressSpace() != DstPTy->getAddressSpace())
+      return 0;
+    
     // If we are casting a malloc or alloca to a pointer to a type of the same
     // size, rewrite the allocation instruction to allocate the "right" type.
     if (AllocationInst *AI = dyn_cast<AllocationInst>(Src))