[llvm] [DAG] Refactor X86 combineVSelectWithAllOnesOrZeros fold into a generic DAG Combine (PR #145298)

[Simon Pilgrim via llvm-commits]

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@@ -150,7 +151,8 @@ define <16 x i8> @sign_16xi8(<16 x i8> %a) {
 define <3 x i32> @sign_3xi32(<3 x i32> %a) {
 ; CHECK-LABEL: sign_3xi32:
 ; CHECK:       // %bb.0:
-; CHECK-NEXT:    cmlt v0.4s, v0.4s, #0
+; CHECK-NEXT:    movi v1.2d, #0xffffffffffffffff
+; CHECK-NEXT:    cmge v0.4s, v1.4s, v0.4s
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RKSimon wrote:

regression?

https://github.com/llvm/llvm-project/pull/145298