[llvm] [LoopVectorize][X86] Improve libmvec SSE/AVX/AVX-512 test coverage (PR #211863)

[Simon Pilgrim via llvm-commits]

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@@ -795,13 +1127,10 @@ for.body:
   store double %call, ptr %arrayidx, align 8
   %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
   %exitcond = icmp eq i64 %indvars.iv.next, 1000
-  br i1 %exitcond, label %for.end, label %for.body, !llvm.loop !179
+  br i1 %exitcond, label %for.end, label %for.body
 
 for.end:
   ret void
 }
-
-!179 = distinct !{!179, !180, !181}
-!180 = !{!"llvm.loop.vectorize.width", i32 2}
-!181 = !{!"llvm.loop.vectorize.enable", i1 true}
-
+;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
+; CHECK: {{.*}}
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RKSimon wrote:

drop CHECK

https://github.com/llvm/llvm-project/pull/211863