[PATCH] D52570: [X86] Don't generate BMI BEXTR from X86DAGToDAGISel::matchBEXTRFromAnd

[Craig Topper via Phabricator via llvm-commits]

craig.topper added a comment.

Forgot to mention that BEXTR breaks the two addressness of the shift+and pattern to avoid a copy which can also be beneficial. Unfortunately isel can't generally determine that a copy will be needed.

I agree, I don't really want to add a new fast/slow flag either.


https://reviews.llvm.org/D52570