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

[Simon Pilgrim via llvm-commits]

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@@ -114,9 +114,10 @@ define i64 @not_sign_i64_4(i64 %a) {
 define <7 x i8> @sign_7xi8(<7 x i8> %a) {
 ; CHECK-LABEL: sign_7xi8:
 ; CHECK:       // %bb.0:
-; CHECK-NEXT:    movi v1.8b, #1
-; CHECK-NEXT:    cmlt v0.8b, v0.8b, #0
-; CHECK-NEXT:    orr v0.8b, v0.8b, v1.8b
+; CHECK-NEXT:    movi v1.2d, #0xffffffffffffffff
+; CHECK-NEXT:    movi v2.8b, #1
+; CHECK-NEXT:    cmge v0.8b, v1.8b, v0.8b
+; CHECK-NEXT:    orr v0.8b, v0.8b, v2.8b
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RKSimon wrote:

regression?

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