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

[Sanjay Patel via Phabricator via llvm-commits]

spatel added a comment.

In https://reviews.llvm.org/D52570#1248819, @lebedev.ri wrote:

> In https://reviews.llvm.org/D52570#1248811, @RKSimon wrote:
>
> > In the short term I think a fast feature flag (for bdver/btver/znver amd targets) is the way to go
>
>
> Hm, but those *are* all the AMD targets that support BMI.
>  Perhaps this can be simplified down to `isAMD()` ?


No - it is never a good idea to map a uarch feature/bug onto a model/vendor predicate. It usually becomes an inaccurate description at some point because companies and chips change. We've experienced this problem in x86 already with "isAtom()".


https://reviews.llvm.org/D52570