[llvm] [SLP] Make getSameOpcode support interchangeable instructions. (PR #127450)

[Han-Kuan Chen via llvm-commits]

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@@ -5,11 +5,19 @@ define i64 @test() {
 ; CHECK-LABEL: define i64 @test() {
 ; CHECK-NEXT:  [[ENTRY:.*:]]
 ; CHECK-NEXT:    [[OR54_I_I_6:%.*]] = or i32 0, 0
-; CHECK-NEXT:    [[TMP0:%.*]] = insertelement <16 x i32> poison, i32 [[OR54_I_I_6]], i32 8
-; CHECK-NEXT:    [[TMP1:%.*]] = call <16 x i32> @llvm.vector.insert.v16i32.v8i32(<16 x i32> [[TMP0]], <8 x i32> zeroinitializer, i64 0)
-; CHECK-NEXT:    [[TMP2:%.*]] = shufflevector <16 x i32> [[TMP1]], <16 x i32> poison, <16 x i32> <i32 0, i32 0, i32 1, i32 1, i32 2, i32 2, i32 3, i32 3, i32 4, i32 4, i32 5, i32 5, i32 6, i32 7, i32 7, i32 8>
-; CHECK-NEXT:    [[TMP3:%.*]] = zext <16 x i32> [[TMP2]] to <16 x i64>
-; CHECK-NEXT:    [[TMP4:%.*]] = call i64 @llvm.vector.reduce.or.v16i64(<16 x i64> [[TMP3]])
+; CHECK-NEXT:    [[CONV193_1_I_6:%.*]] = zext i32 [[OR54_I_I_6]] to i64
+; CHECK-NEXT:    [[CONV193_I_7:%.*]] = zext i32 0 to i64
+; CHECK-NEXT:    [[TMP0:%.*]] = call <4 x i64> @llvm.vector.extract.v4i64.v8i64(<8 x i64> zeroinitializer, i64 0)
+; CHECK-NEXT:    [[RDX_OP:%.*]] = or <4 x i64> [[TMP0]], zeroinitializer
+; CHECK-NEXT:    [[TMP1:%.*]] = call <8 x i64> @llvm.vector.insert.v8i64.v4i64(<8 x i64> zeroinitializer, <4 x i64> [[RDX_OP]], i64 0)
+; CHECK-NEXT:    [[OP_RDX:%.*]] = call i64 @llvm.vector.reduce.or.v8i64(<8 x i64> [[TMP1]])
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HanKuanChen wrote:

Yes. We can get this without 4a08497fcc1ec161ee2bb0686364405faecdef37 if we make `%or54.i.i.6 = or i32 %xor148.2.i.6, 0` to `%or54.i.i.6 = xor i32 %xor148.2.i.6, 0`.

https://github.com/llvm/llvm-project/pull/127450