[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;
+#include "llvm/BinaryFormat/DXContainerConstants.def"
+    return ModuleFlags;
+  }
+
+  void merge(const uint64_t IVal) {
+#define SHADER_FEATURE_FLAG(FeatureBit, DxilModuleBit, FlagName, Str)          \
+  FlagName |= (IVal & getMask(DxilModuleBit));
+#define DXIL_MODULE_FLAG(DxilModuleBit, FlagName, Str)                         \
+  FlagName |= (IVal & getMask(DxilModuleBit));
+#include "llvm/BinaryFormat/DXContainerConstants.def"
+    return;
+  }
+
   void print(raw_ostream &OS = dbgs()) const;
   LLVM_DUMP_METHOD void dump() const { print(); }
 };
 
+struct DXILModuleShaderFlagsInfo {
+  DXILModuleShaderFlagsInfo(const Module &);
+  Expected<const ComputedShaderFlags &>
+  getShaderFlagsMask(const Function *) const;
+  const ComputedShaderFlags getCombinedFlags() const;
+
+private:
+  /// Vector of Function-Shader Flag mask pairs representing properties of each
+  /// of the functions in the module. Shader Flags of each function represent
+  /// both module-level and function-level flags
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bharadwajy wrote:

> Worth noting that this is a sorted vector.

Updated comment accordingly.

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