[PATCH] D65132: [X86] In lowerVectorShuffle, instead of creating a new node to canonicalize the shuffle mask by commuting, just commute the mask and swap V1/V2.

[Craig Topper via Phabricator via llvm-commits]

craig.topper marked an inline comment as done.
craig.topper added inline comments.


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Comment at: llvm/test/CodeGen/X86/vector-shuffle-128-v2.ll:721
 ; SSE2:       # %bb.0:
-; SSE2-NEXT:    xorpd %xmm1, %xmm1
-; SSE2-NEXT:    movsd {{.*#+}} xmm0 = xmm1[0],xmm0[1]
+; SSE2-NEXT:    xorps %xmm1, %xmm1
+; SSE2-NEXT:    unpckhpd {{.*#+}} xmm1 = xmm1[1],xmm0[1]
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Not sure if this should be considered a regression or not. The types are integers here so we're really matching an integer unpckh during shuffle lowering. We don't have an equivalent of movsd in the integer domain. Only later does the execution domain fixing pass move it to FP.


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  https://reviews.llvm.org/D65132/new/

https://reviews.llvm.org/D65132