[llvm] [VectorCombine] foldPermuteOfBinops - fold "shuffle (binop (shuffle, other)), undef" --> "binop (shuffle), (shuffle)". (PR #122118)

[Alexey Bataev via llvm-commits]

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@@ -820,9 +820,9 @@ define <2 x double> @add_v2f64_u1(<2 x double> %a, <2 x double> %b) {
 
 define <2 x double> @add_v2f64_0u(<2 x double> %a, <2 x double> %b) {
 ; CHECK-LABEL: @add_v2f64_0u(
-; CHECK-NEXT:    [[SHIFT:%.*]] = shufflevector <2 x double> [[A:%.*]], <2 x double> poison, <2 x i32> <i32 1, i32 poison>
-; CHECK-NEXT:    [[TMP1:%.*]] = fadd <2 x double> [[A]], [[SHIFT]]
-; CHECK-NEXT:    [[RESULT:%.*]] = shufflevector <2 x double> [[TMP1]], <2 x double> poison, <2 x i32> <i32 0, i32 poison>
+; CHECK-NEXT:    [[TMP1:%.*]] = shufflevector <2 x double> [[A:%.*]], <2 x double> poison, <2 x i32> <i32 0, i32 poison>
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alexey-bataev wrote:

Should this be just `A`?

https://github.com/llvm/llvm-project/pull/122118