[llvm] [InstCombine] Fold shuffles through all trivially vectorizable intrinsics (PR #141979)

[Yingwei Zheng via llvm-commits]

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@@ -264,23 +264,17 @@ define <3 x i16> @uadd_sat_v3i16(<3 x i16> %arg0, <3 x i16> %arg1) {
 ; GFX8-NEXT:  bb:
 ; GFX8-NEXT:    [[ARG0_2:%.*]] = extractelement <3 x i16> [[ARG0:%.*]], i64 2
 ; GFX8-NEXT:    [[ARG1_2:%.*]] = extractelement <3 x i16> [[ARG1:%.*]], i64 2
-; GFX8-NEXT:    [[TMP0:%.*]] = shufflevector <3 x i16> [[ARG0]], <3 x i16> poison, <2 x i32> <i32 0, i32 1>
-; GFX8-NEXT:    [[TMP1:%.*]] = shufflevector <3 x i16> [[ARG1]], <3 x i16> poison, <2 x i32> <i32 0, i32 1>
-; GFX8-NEXT:    [[TMP2:%.*]] = call <2 x i16> @llvm.uadd.sat.v2i16(<2 x i16> [[TMP0]], <2 x i16> [[TMP1]])
+; GFX8-NEXT:    [[TMP3:%.*]] = call <3 x i16> @llvm.uadd.sat.v3i16(<3 x i16> [[ARG0]], <3 x i16> [[ARG1]])
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dtcxzyw wrote:

This fold changes the vector length of intrinsics.


https://github.com/llvm/llvm-project/pull/141979