[PATCH] D119654: [SDAG] enable binop identity constant folds for add/sub

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: llvm/test/CodeGen/X86/srem-seteq-vec-splat.ll:695
+; CHECK-AVX512VL-NEXT:    vpcmpeqd %xmm1, %xmm0, %xmm0
+; CHECK-AVX512VL-NEXT:    vpsrld $31, %xmm0, %xmm0
 ; CHECK-AVX512VL-NEXT:    retq
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RKSimon wrote:
> Any chance you can track down the missing combine please?
> 
> The ISD::SUB should definitely fold away, not sure if the ISD::XOR is a zeroinitializer or not - but X86ISD::PCMPEQ will fold to all ones if the inputs are equal. And we should have constant folding for X86ISD::VSRLI
Sorry - missed your reply above!


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  https://reviews.llvm.org/D119654/new/

https://reviews.llvm.org/D119654