[PATCH] D36890: [X86] Emit testl instead of testb for select condition where possible

[Alexander Ivchenko via Phabricator via llvm-commits]

aivchenk added a comment.

yeah, now I also think that I covered only a narrow case for the issue: we need more general approach.

My 2 cents on your points:

1. If the result of AssertZext is truncated with no other uses, can we just delete that AssertZext? What value does it bring if all bits that are supposed to be zeroed just being thrown away? Or the case here would be that zero extend was e.g. to 32 bits but we truncate e.g. to 16? Could you please share the x86 test changes after your patch?
2. I think this is the right thing to do :)


https://reviews.llvm.org/D36890