[llvm] [GVNSink] Fix non-determinisms by using Depth-First ordering (PR #90995)

[Paul Kirth via llvm-commits]

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@@ -28,3 +28,27 @@ if.end:
   ret float %phi
 }
 
+; CHECK-LABEL: scalarsSinkingReverse
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ilovepi wrote:

can you add that detail as a comment in the test. This seems like something that could get lost and cause the test to be removed.

https://github.com/llvm/llvm-project/pull/90995