[PATCH] D20555: [MemCpyOpt] Be conservative in the face of returns_twice calls

[Reid Kleckner via llvm-commits]

rnk added a comment.

I think the right fix is declare that volatile loads and stores "capture" their pointer operands, or to tease out some other function attribute like that. Your reduced test case from IRC shows how we incorrectly redirect volatile stores from y to x: https://ghostbin.com/paste/v5n3f


http://reviews.llvm.org/D20555