[llvm] [DAG] isSplatValue - node is a splat if all demanded elts have the same whole constant value (PR #74443)

[Phoebe Wang via llvm-commits]

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@@ -25,18 +25,20 @@ define <4 x i64> @var_shuffle_v4i64(<4 x i64> %v, <4 x i64> %indices) nounwind {
 ;
 ; AVX1-LABEL: var_shuffle_v4i64:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    vperm2f128 {{.*#+}} ymm2 = ymm0[2,3,2,3]
-; AVX1-NEXT:    vpaddq %xmm1, %xmm1, %xmm3
-; AVX1-NEXT:    vextractf128 $1, %ymm1, %xmm1
+; AVX1-NEXT:    vextractf128 $1, %ymm1, %xmm2
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phoebewang wrote:

Didn't look into details, but the RHS has more instructions. Is it intended?

https://github.com/llvm/llvm-project/pull/74443