[PATCH] D132978: [CodeGen] Using ZExt for extractelement indices.

[Peter Rong via Phabricator via llvm-commits]

Peter added inline comments.


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Comment at: llvm/test/CodeGen/X86/var-permute-128.ll:132
 ; SSE3:       # %bb.0:
-; SSE3-NEXT:    movd %xmm1, %r8d
+; SSE3-NEXT:    pextrw $0, %xmm1, %r8d
 ; SSE3-NEXT:    pextrw $1, %xmm1, %r9d
----------------
RKSimon wrote:
> These are mildly annoying, on some targets movd is notably quicker than pextr* - I think we're just missing a SimplifyDemandedBits handler though.
I just checked the documentation of both instructions. It seems you are right. 
Is there anything you hoped we could've done differently, or it is another issue? 


Repository:
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  https://reviews.llvm.org/D132978/new/

https://reviews.llvm.org/D132978