[llvm] [DirectX] Infrastructure to collect shader flags for each function (PR #112967)

[S. Bharadwaj Yadavalli via llvm-commits]

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@@ -120,16 +127,17 @@ class ShaderFlagsAnalysisPrinter
 /// This is required because the passes that will depend on this are codegen
 /// passes which run through the legacy pass manager.
 class ShaderFlagsAnalysisWrapper : public ModulePass {
-  DXILModuleShaderFlagsInfo MSFI;
+  std::unique_ptr<DXILModuleShaderFlagsInfo> MSFI;
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bharadwajy wrote:

> +1
> 
> I also question if we need the optional. Why was the old pattern of the uninitialized flag structure a problem?

Reverted to old pattern; changed to use `initialize()` instead of a constructor to avoid dynamic memory allocation about which concerns were expressed. 

https://github.com/llvm/llvm-project/pull/112967