[clang] [llvm] [HLSL][RootSignature] Add infastructure to parse parameters (PR #133800)

[Finn Plummer via llvm-commits]

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@@ -32,11 +39,19 @@ struct DescriptorTable {
 using ClauseType = llvm::dxil::ResourceClass;
 struct DescriptorTableClause {
   ClauseType Type;
+  Register Register;
+  uint32_t Space = 0;
 };
 
 // Models RootElement : DescriptorTable | DescriptorTableClause
 using RootElement = std::variant<DescriptorTable, DescriptorTableClause>;
 
+// ParamType is used as an 'any' type that will reference to a parameter in
+// RootElement. Each variant of ParamType is expected to have a Parse method
+// defined that will be dispatched on when we are attempting to parse a
+// parameter
+using ParamType = std::variant<uint32_t *, Register *>;
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inbelic wrote:

This is probably better moved to `ParseHLSLRootSignature.h` since it is specific to there

https://github.com/llvm/llvm-project/pull/133800