[llvm] [AMDGPU] Do not preserve UniformityInfo (PR #76696)

[Matt Arsenault via llvm-commits]

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@@ -85,7 +85,6 @@ class AMDGPURewriteUndefForPHILegacy : public FunctionPass {
     AU.addRequired<DominatorTreeWrapperPass>();
 
     AU.addPreserved<DominatorTreeWrapperPass>();
-    AU.addPreserved<UniformityInfoWrapperPass>();
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arsenm wrote:

Probably should add an explanatory comment 

https://github.com/llvm/llvm-project/pull/76696