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

[via llvm-commits]

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

This test is just a reverse of the test above to ensure GVNSink doesn't depend on the order of branches.

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