[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:

Is it correct to say that this preserves all? I'm not sure if any analyses cache information about function attributes, so maybe it's okay there, but we do modify the IR so I doubt it's safe to really say we preserve all analyses...

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