Add implementations of the MSVC barrier intrinsics
Summary:
These are deprecated in VS 2012 according to MSDN. They don't actually
compile down to any code. They prevent the compiler from reordering
memory accesses across the barrier, which is what a memory-clobbering
volatile asm does.
Reviewers: echristo
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1954
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@192860 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed