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

[S. Bharadwaj Yadavalli via llvm-commits]

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@@ -60,21 +62,54 @@ struct ComputedShaderFlags {
     return FeatureFlags;
   }
 
-  static ComputedShaderFlags computeFlags(Module &M);
+  uint64_t getModuleFlags() const {
+    uint64_t ModuleFlags = 0;
+#define DXIL_MODULE_FLAG(DxilModuleBit, FlagName, Str)                         \
+  ModuleFlags |= FlagName ? getMask(DxilModuleBit) : 0ull;
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bharadwajy wrote:

> We have this exact expansion inside the `operator uint64_t` definition above. Should we maybe refactor this so that one uses the other instead of duplicating the expansion?

Refactored.

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