[PATCH] D38616: [RegisterCoalescer] Don't set read-undef if there is a previous def

[Mikael Holmén via Phabricator via llvm-commits]

uabelho added a comment.

We ran into this problem on our out-of-tree target, but I've tried to make a reasonable test case
for X86.

Does this change make sense to you? We've run with it locally for quite some time now and it
solves our problem and hasn't introduced new ones that we are aware of. I don't know this code
though so maybe there is a better fix?


https://reviews.llvm.org/D38616