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

[Alexey Bataev via llvm-commits]

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@@ -801,10 +801,10 @@ define <2 x double> @sub_v2f64_01(<2 x double> %a, <2 x double> %b) {
 
 define <2 x double> @sub_v2f64_u1(<2 x double> %a, <2 x double> %b) {
 ; CHECK-LABEL: @sub_v2f64_u1(
-; CHECK-NEXT:    [[SHIFT:%.*]] = shufflevector <2 x double> [[B:%.*]], <2 x double> poison, <2 x i32> <i32 1, i32 poison>
-; CHECK-NEXT:    [[TMP1:%.*]] = fsub <2 x double> [[B]], [[SHIFT]]
-; CHECK-NEXT:    [[RESULT:%.*]] = shufflevector <2 x double> [[TMP1]], <2 x double> poison, <2 x i32> <i32 poison, i32 0>
-; CHECK-NEXT:    ret <2 x double> [[RESULT]]
+; CHECK-NEXT:    [[RESULT:%.*]] = shufflevector <2 x double> [[TMP1:%.*]], <2 x double> poison, <2 x i32> <i32 poison, i32 0>
+; CHECK-NEXT:    [[TMP2:%.*]] = shufflevector <2 x double> [[TMP1]], <2 x double> poison, <2 x i32> <i32 poison, i32 1>
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alexey-bataev wrote:

Just `TMP1`?

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