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

[Simon Pilgrim via llvm-commits]

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@@ -643,3 +618,6 @@ define void @min_v2f64(ptr %c, ptr %a, ptr %b) nounwind {
   store <2 x double> %3, ptr %c
   ret void
 }
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; MIPS: {{.*}}
+; MIPSEL: {{.*}}
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RKSimon wrote:

you can remove the check-prefixes= lines from the RUNs at the top of the file now (default is CHECK) and this will disappear

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