[llvm] [VectorCombine] foldShuffleOfCastops - handle unary shuffles (PR #160009)

[Chaitanya Koparkar via llvm-commits]

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@@ -922,10 +922,9 @@ define <4 x i8> @singleop(<4 x i8> %a, <4 x i8> %b) {
 
 define <4 x i64> @cast_mismatched_types(<4 x i32> %x) {
 ; CHECK-LABEL: @cast_mismatched_types(
-; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <4 x i32> [[X:%.*]], <4 x i32> poison, <2 x i32> <i32 0, i32 2>
-; CHECK-NEXT:    [[ZEXT:%.*]] = zext <2 x i32> [[SHUF]] to <2 x i64>
-; CHECK-NEXT:    [[EXTSHUF:%.*]] = shufflevector <2 x i64> [[ZEXT]], <2 x i64> poison, <4 x i32> <i32 0, i32 2, i32 1, i32 3>
-; CHECK-NEXT:    ret <4 x i64> [[EXTSHUF]]
+; CHECK-SAME: <4 x i32> [[X:%.*]]) {
+; CHECK-NEXT:    [[ZEXT:%.*]] = zext <4 x i32> [[X]] to <4 x i64>
+; CHECK-NEXT:    ret <4 x i64> [[ZEXT]]
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ckoparkar wrote:

Very cool, it didn't occur to me to check this with Alive. I'll keep it in mind for future. Thanks for checking :-)

https://github.com/llvm/llvm-project/pull/160009