[PATCH] D110995: [X86] combineMulToPMADDWD - handle any pow2 vector type and split to legal types

[Phoebe Wang via Phabricator via llvm-commits]

pengfei added inline comments.


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Comment at: llvm/test/CodeGen/X86/shrink_vmul.ll:992
 ; X86-SSE-NEXT:    punpcklbw {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3],xmm1[4],xmm2[4],xmm1[5],xmm2[5],xmm1[6],xmm2[6],xmm1[7],xmm2[7]
-; X86-SSE-NEXT:    punpcklwd {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3]
-; X86-SSE-NEXT:    pmaddwd %xmm0, %xmm1
-; X86-SSE-NEXT:    movq %xmm1, (%ecx,%eax,4)
+; X86-SSE-NEXT:    pshuflw {{.*#+}} xmm1 = xmm1[0,1,1,3,4,5,6,7]
+; X86-SSE-NEXT:    punpcklbw {{.*#+}} xmm0 = xmm0[0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7]
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The shuffle looks odd. What's its equivalent in the left?


Repository:
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  https://reviews.llvm.org/D110995/new/

https://reviews.llvm.org/D110995