Merging r182387:

------------------------------------------------------------------------
r182387 | jholewinski | 2013-05-21 07:37:16 -0700 (Tue, 21 May 2013) | 7 lines

Drop @llvm.annotation and @llvm.ptr.annotation intrinsics during codegen.

The intrinsic calls are dropped, but the annotated value is propagated.

Fixes PR 15253

Original patch by Zeng Bin!
------------------------------------------------------------------------

llvm-svn: 182417