[llvm] [DXIL] Consume Metadata Analysis information in passes (PR #108034)

[Justin Bogner via llvm-commits]

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@@ -247,9 +247,10 @@ class DXILPrepareModule : public ModulePass {
 
   DXILPrepareModule() : ModulePass(ID) {}
   void getAnalysisUsage(AnalysisUsage &AU) const override {
+    AU.setPreservesAll();
     AU.addPreserved<ShaderFlagsAnalysisWrapper>();
     AU.addPreserved<DXILResourceMDWrapper>();
-    AU.addPreserved<DXILMetadataAnalysisWrapperPass>();
+    AU.addRequired<DXILMetadataAnalysisWrapperPass>();
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bogner wrote:

I still don't understand why we would change this to `setPreservesAll`. If you just need to preserve `DXILMetadataAnalysis` then the existing `AU.addPreserved<DXILMetadataAnalysisWrapperPass>()` call should do that, no?

https://github.com/llvm/llvm-project/pull/108034