[PATCH] D19659: [X86] Enable RRL part of the LEA optimization pass for -O2

[Andrey Turetskiy via llvm-commits]

aturetsk added a comment.

Hi Quentin,

Yes. When I was implementing the pass my primary target was code size, so I didn't check performance impact extensively (I checked only that there was no significant degradation on a couple of benchmarks). The obvious concern was that the RRL part of the pass may increase register pressure and that would hurt performance. The code size impact was really small so it was easier and safer to just enable it only for -Oz.


http://reviews.llvm.org/D19659