[llvm] [DirectX] Add DXIL validation of `llvm.loop` metadata (PR #164292)

[Finn Plummer via llvm-commits]

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@@ -24,9 +24,10 @@ _Z4mainDv3_j.exit:                                ; preds = %for.body.i, %entry
 ; These next check lines check that only the range metadata remains
 ; No more metadata should be necessary, the rest (the current 0 and 1)
 ; should be removed.
-; CHECK-NOT: !{!"llvm.loop.mustprogress"}
-; CHECK: [[RANGEMD]] = !{i32 1, i32 5}
-; CHECK-NOT: !{!"llvm.loop.mustprogress"}
+; CHECK-NOT: {!"llvm.loop.mustprogress"}
+; CHECK-DAG: [[RANGEMD]] = !{i32 1, i32 5}
+; CHECK-DAG: [[LOOPMD]] = distinct !{[[LOOPMD]]}
+; CHECK-NOT: {!"llvm.loop.mustprogress"}
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inbelic wrote:

```suggestion
; CHECK-NOT: !{!"llvm.loop.mustprogress"}
```

https://github.com/llvm/llvm-project/pull/164292