src/tint/lang/core/ir/let.h

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#ifndef SRC_TINT_LANG_CORE_IR_LET_H_
#define SRC_TINT_LANG_CORE_IR_LET_H_

#include <string>

#include "src/tint/lang/core/ir/operand_instruction.h"

namespace tint::core::ir {

/// A no-op instruction in the IR, used to position and name a value
class Let final : public Castable<Let, OperandInstruction<1, 1>> {
  public:
    /// The offset in Operands() for the value
    static constexpr size_t kValueOperandOffset = 0;

    /// The fixed number of results returned by let instructions
    static constexpr size_t kNumResults = 1;

    /// The fixed number of operands accepted by let instructions
    static constexpr size_t kNumOperands = 1;

    /// Constructor (no result, no operands)
    /// @param id the instruction id
    explicit Let(Id id);

    /// Constructor
    /// @param id the instruction id
    /// @param result the result value
    /// @param value the let's value
    Let(Id id, InstructionResult* result, Value* value);

    ~Let() override;

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

    /// @param value the new let value
    void SetValue(ir::Value* value) { SetOperand(kValueOperandOffset, value); }

    /// @returns the value
    ir::Value* Value() { return Operand(kValueOperandOffset); }

    /// @returns the value
    const ir::Value* Value() const { return Operand(kValueOperandOffset); }

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

}  // namespace tint::core::ir

#endif  // SRC_TINT_LANG_CORE_IR_LET_H_