[llvm] [DirectX] Add Range Overlap validation (PR #152229)

[Finn Plummer via llvm-commits]

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@@ -125,10 +291,13 @@ class DXILPostOptimizationValidationLegacy : public ModulePass {
   void getAnalysisUsage(llvm::AnalysisUsage &AU) const override {
     AU.addRequired<DXILResourceWrapperPass>();
     AU.addRequired<DXILResourceBindingWrapperPass>();
+    AU.addRequired<DXILMetadataAnalysisWrapperPass>();
+    AU.addRequired<RootSignatureAnalysisWrapper>();
     AU.addPreserved<DXILResourceWrapperPass>();
     AU.addPreserved<DXILResourceBindingWrapperPass>();
     AU.addPreserved<DXILMetadataAnalysisWrapperPass>();
     AU.addPreserved<ShaderFlagsAnalysisWrapper>();
+    AU.addPreserved<RootSignatureAnalysisWrapper>();
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inbelic wrote:

What do `addRequired` and `addPreserved` do? Not saying anything is wrong, I just don't understand.

https://github.com/llvm/llvm-project/pull/152229