V-Gears/V-Gears-Installer/include/decompiler/field/instruction/FieldMathInstruction.h

/*
 * Copyright (C) 2022 V-Gears Team
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#pragma once

#include "decompiler/instruction.h"
#include "decompiler/field/FieldEngine.h"

namespace FF7{

    /**
     * A math instruction.
     */
    class FieldMathInstruction : public StoreInstruction{

        public:

            /**
             * Processes the instruction.
             *
             * @param func[in] Function to process.
             * @param stack[out] Function stack.
             * @param engine[in] Engine. Unused.
             * @param code_gen[in] Code generator.
             */
            virtual void ProcessInst(
              Function& func, ValueStack &stack, Engine *engine, CodeGenerator *code_gen
            ) override;

        private:

            void ProcessSaturatedPLUS(CodeGenerator* code_gen);
            void ProcessSaturatedPLUS2(CodeGenerator* code_gen);
            void ProcessSaturatedMINUS(CodeGenerator* code_gen);
            void ProcessSaturatedMINUS2(CodeGenerator* code_gen);
            void ProcessSaturatedINC(CodeGenerator* code_gen);
            void ProcessSaturatedINC2(CodeGenerator* code_gen);
            void ProcessSaturatedDEC(CodeGenerator* code_gen);
            void ProcessSaturatedDEC2(CodeGenerator* code_gen);
            void ProcessRDMSD(CodeGenerator* code_gen);
            void ProcessSETBYTE_SETWORD(CodeGenerator* code_gen);

            /**
             * Processes a BITON opcode.
             *
             * Opcode: 0x82
             * Short name: BITON
             * Long name: Set Bit
             *
             * Memory layout (4 bytes)
             * |0x82|D/S|A|B|
             *
             * Arguments
             * - const Bit[4] D: Destination bank.
             * - const Bit[4] S: Source bank.
             * - const UByte A: Destination address.
             * - const UByte Bit: The number of the bit to turn on.
             *
             * Sets the nth bit in the "A" location, where n is a number
             * between 0-7 supplied in B. A value of zero in B will set the
             * least significant bit. If the Source Bank is 0 then the bit to
             * be set is taken from "Bit". If the Source Bank is an 8 bit
             * bank, then the bit is the address in that bank where the
             * operand is.
             *
             * @param codegen[in|out] Code generator to append lines.
             */
            void ProcessBITON(CodeGenerator* code_gen);

            /**
             * Processes a BITON opcode.
             *
             * Opcode: 0x83
             * Short name: BITOFF
             * Long name: Reset Bit
             *
             * Memory layout (4 bytes)
             * |0x83|D/S|A|B|
             *
             * Arguments
             * - const Bit[4] D: Destination bank.
             * - const Bit[4] S: Source bank.
             * - const UByte A: Destination address.
             * - const UByte Bit: The number of the bit to turn off.
             *
             * Sets the nth bit in the "A" location, where n is a number
             * between 0-7 supplied in B. A value of zero in B will reset the
             * least significant bit. If the Source Bank is 0 then the bit to
             * be set is taken from "Bit". If the Source Bank is an 8 bit
             * bank, then the bit is the address in that bank where the
             * operand is.
             *
             * @param codegen[in|out] Code generator to append lines.
             */
            void ProcessBITOFF(CodeGenerator* code_gen);
            void ProcessPLUSx_MINUSx(CodeGenerator* code_gen, const std::string& op);
            void ProcessINCx_DECx(CodeGenerator* code_gen, const std::string& op);
            void ProcessRANDOM(CodeGenerator* code_gen);
    };

}