Preserve 'nonnull' when changing type of the load.

When changing the type of a load in Chandler's recent InstCombine changes, we can preserve the new 'nonnull' metadata.  

I considered adding an assert since 'nonnull' is only valid on pointer types, but casting a pointer to a non-pointer would involve more than a bitcast anyways.  If someone extends this transform to handle more than bitcasts, the verifier will report the malformed IR, so a separate assertion isn't needed.  Also, the fpmath flags would have the same problem.

llvm-svn: 220324

1 files changed, 1 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
index 95ca1a6ff7a..c0df914cb66 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -331,6 +331,7 @@ static LoadInst *combineLoadToNewType(InstCombiner &IC, LoadInst &LI, Type *NewT
     case LLVMContext::MD_noalias:
     case LLVMContext::MD_nontemporal:
     case LLVMContext::MD_mem_parallel_loop_access:
+    case LLVMContext::MD_nonnull:
       // All of these directly apply.
       NewLoad->setMetadata(ID, N);
       break;