[PATCH] D47202: [CodeGen] use nsw negation for abs

[Roman Lebedev via Phabricator via cfe-commits]

lebedev.ri added a comment.

That is what happens for "hand-rolled" `abs`, https://godbolt.org/g/6dbgXD
I *think* this makes sense, since **IIRC** LLVM only supports twos-complement platforms.
But all these attributes are currently beyond me, so i won't click the accept button :)


https://reviews.llvm.org/D47202