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#ifndef SRC_TINT_LANG_CORE_IR_OVERRIDE_H_
#define SRC_TINT_LANG_CORE_IR_OVERRIDE_H_

#include <string>

#include "src/tint/api/common/override_id.h"
#include "src/tint/lang/core/ir/operand_instruction.h"
#include "src/tint/utils/rtti/castable.h"

namespace tint::core::ir {

/// A var instruction in the IR.
class Override final : public Castable<Override, OperandInstruction<1, 1>> {
  public:
    /// The offset in Operands() for the initializer
    static constexpr size_t kInitializerOperandOffset = 0;

    /// The fixed number of results returned by this instruction
    static constexpr size_t kNumResults = 1;

    /// Constructor (no results, no operands)
    /// @param id the instruction id
    explicit Override(Id id);

    /// Constructor
    /// @param id the instruction id
    /// @param result the result value
    Override(Id id, InstructionResult* result);

    ~Override() override;

    /// @copydoc Instruction::Clone()
    Override* Clone(CloneContext& ctx) override;

    /// Sets the var initializer
    /// @param initializer the initializer
    void SetInitializer(Value* initializer);
    /// @returns the initializer
    Value* Initializer() { return Operand(kInitializerOperandOffset); }
    /// @returns the initializer
    const Value* Initializer() const { return Operand(kInitializerOperandOffset); }

    /// Sets the override Id attribute
    /// @param id the override id
    void SetOverrideId(OverrideId id) { override_id_ = id; }
    /// @returns the override ID
    std::optional<tint::OverrideId> OverrideId() const { return override_id_; }

    /// @returns the friendly name for the instruction
    std::string FriendlyName() const override { return "override"; }

  private:
    std::optional<tint::OverrideId> override_id_{};
};

}  // namespace tint::core::ir

#endif  // SRC_TINT_LANG_CORE_IR_OVERRIDE_H_
