[llvm] [DXIL] Add constraint specification and backend implementation of DXIL Ops (PR #97593)

[S. Bharadwaj Yadavalli via llvm-commits]

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@@ -30,13 +31,21 @@ class DXILOpBuilder {
 public:
   DXILOpBuilder(Module &M, IRBuilderBase &B) : M(M), B(B) {}
   /// Create an instruction that calls DXIL Op with return type, specified
-  /// opcode, and call arguments. \param OpCode Opcode of the DXIL Op call
-  /// constructed \param ReturnTy Return type of the DXIL Op call constructed
+  /// opcode, and call arguments.
+  ///
+  /// \param OpCode Opcode of the DXIL Op call constructed
+  /// \param SMVer Shader Model Version of DXIL Module being constructed.
+  /// \param StageKind Shader Stage for DXIL Module being constructed.
+  /// \param ReturnTy Return type of the DXIL Op call constructed
   /// \param OverloadTy Overload type of the DXIL Op call constructed
+  /// \param Args Arguments for the DXIL Op call constructed
   /// \return DXIL Op call constructed
-  CallInst *createDXILOpCall(dxil::OpCode OpCode, Type *ReturnTy,
+  CallInst *createDXILOpCall(dxil::OpCode OpCode, VersionTuple SMVer,
+                             StringRef StageKind, Type *ReturnTy,
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bharadwajy wrote:

> Why StageKind is a StringRef instead of enum for shader stages?

Do you think it is safer and/or more beneficial to pass the enum obtained by calling `getShaderkKindEnum(...)` at the call site `DXILOpLowering.cpp::lowerIntrinsic(...)`, instead of doing so this function?


https://github.com/llvm/llvm-project/pull/97593