// Copyright Jamie Iles, 2017
//
// This file is part of s80x86.
//
// s80x86 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.
//
// s80x86 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 s80x86.  If not, see <http://www.gnu.org/licenses/>.

// MOV 0x88     r/m := r (8-bit)
.at 0x88;
    mar_write, mar_wr_sel EA, width W8, jmp_rm_reg_mem mov88_reg;
// MOV 0x89     r/m := r (16-bit)
.at 0x89;
    mar_write, mar_wr_sel EA, jmp_rm_reg_mem mov88_reg;
.auto_address;
mov88_reg:
    b_sel RB, alu_op SELB, rd_sel_source MODRM_RM_REG,
        width WAUTO, next_instruction;
mov88_mem:
    b_sel RB, alu_op SELB, mdr_write, segment DS, jmp write_complete;

// MOV 0x8a     r := r/m (8-bit)
.at 0x8a;
    mar_write, mar_wr_sel EA, ra_modrm_rm_reg, width W8,
        jmp_rm_reg_mem mov8a_reg, segment DS, a_sel RA;
// MOV 0x8b     r := r/m (16-bit)
.at 0x8b;
    mar_write, mar_wr_sel EA, ra_modrm_rm_reg,
        jmp_rm_reg_mem mov8a_reg, a_sel RA, segment DS;
.auto_address;
mov8a_reg:
    a_sel RA, ra_modrm_rm_reg, alu_op SELA,
        rd_sel_source MODRM_REG, width WAUTO,
        next_instruction;
mov8a_mem:
    mem_read, width WAUTO, segment DS;
    rd_sel_source MODRM_REG, a_sel MDR, alu_op SELA, width WAUTO,
        next_instruction;

// MOV 0xc6     r/m := immed8
.at 0xc6;
    mar_write, mar_wr_sel EA, jmp_dispatch_reg c6_dispatch;
// MOV 0xc7     r/m := immed16
.at 0xc7;
    mar_write, mar_wr_sel EA, jmp_dispatch_reg c6_dispatch;
.auto_address;
c6_dispatch:
    jmp_rm_reg_mem movc6_reg; // reg == 0
    next_instruction; // reg == 1
    next_instruction; // reg == 2
    next_instruction; // reg == 3
    next_instruction; // reg == 4
    next_instruction; // reg == 5
    next_instruction; // reg == 6
    next_instruction; // reg == 7
movc6_reg:
    b_sel IMMEDIATE, alu_op SELB,
        rd_sel_source MODRM_RM_REG, width WAUTO,
        next_instruction;
movc6_mem:
    b_sel IMMEDIATE, alu_op SELB, mdr_write, segment DS, jmp write_complete;

#define MOV_REG_IMMED8(opcode, reg) \
    .at opcode; \
        rd_sel_source MICROCODE_RD_SEL, rd_sel reg, \
            alu_op SELB, b_sel IMMEDIATE, width W8, next_instruction;

MOV_REG_IMMED8(0xb0, AL)
MOV_REG_IMMED8(0xb1, CL)
MOV_REG_IMMED8(0xb2, DL)
MOV_REG_IMMED8(0xb3, BL)
MOV_REG_IMMED8(0xb4, AH)
MOV_REG_IMMED8(0xb5, CH)
MOV_REG_IMMED8(0xb6, DH)
MOV_REG_IMMED8(0xb7, BH)

#define MOV_REG_IMMED16(opcode, reg) \
    .at opcode; \
        rd_sel_source MICROCODE_RD_SEL, rd_sel reg, \
            alu_op SELB, b_sel IMMEDIATE, next_instruction;

MOV_REG_IMMED16(0xb8, AX)
MOV_REG_IMMED16(0xb9, CX)
MOV_REG_IMMED16(0xba, DX)
MOV_REG_IMMED16(0xbb, BX)
MOV_REG_IMMED16(0xbc, SP)
MOV_REG_IMMED16(0xbd, BP)
MOV_REG_IMMED16(0xbe, SI)
MOV_REG_IMMED16(0xbf, DI)

// MOV 0xa0     al := m[immed16]
.at 0xa0;
    mar_write, mar_wr_sel Q, b_sel IMMEDIATE, alu_op SELB, jmp mova0, segment DS;
// MOV 0xa1     ax := m[immed16]
.at 0xa1;
    mar_write, mar_wr_sel Q, b_sel IMMEDIATE, alu_op SELB, jmp mova0, segment DS;
.auto_address;
mova0:
    segment DS, width WAUTO, mem_read;
    rd_sel_source MICROCODE_RD_SEL, rd_sel AL, width WAUTO,
        a_sel MDR, alu_op SELA, next_instruction;

// MOV 0xa2     m[immed16] := al
.at 0xa2;
    mar_write, mar_wr_sel Q, b_sel IMMEDIATE, alu_op SELB, jmp mova2, ra_sel AL;
.at 0xa3;
    mar_write, mar_wr_sel Q, b_sel IMMEDIATE, alu_op SELB, jmp mova2, ra_sel AL;
.auto_address;
mova2:
    a_sel RA, alu_op SELA, mdr_write, segment DS, jmp write_complete;

// MOV 0x8e     sr := reg/mem
.at 0x8e;
    mar_write, mar_wr_sel EA, ra_modrm_rm_reg,
        segment DS, jmp_rm_reg_mem mov8e_reg;
.auto_address;
mov8e_reg:
    segment_wr_en, rd_sel_source MODRM_REG, a_sel RA, alu_op SELA,
        ext_int_inhibit, next_instruction;
mov8e_mem:
    segment DS, mem_read;
    rd_sel_source MODRM_REG, segment_wr_en, a_sel MDR, alu_op SELA,
        ext_int_inhibit, next_instruction;

// MOV 0x8c     reg/mem := sr
.at 0x8c;
    mar_write, mar_wr_sel EA, jmp_dispatch_reg dispatch_8c;
.auto_address;
dispatch_8c:
    segment_force, segment ES, jmp_rm_reg_mem mov8c_reg;
    segment_force, segment CS, jmp_rm_reg_mem mov8c_reg;
    segment_force, segment SS, jmp_rm_reg_mem mov8c_reg;
    segment_force, segment DS, jmp_rm_reg_mem mov8c_reg;
    segment_force, segment ES, jmp_rm_reg_mem mov8c_reg;
    segment_force, segment CS, jmp_rm_reg_mem mov8c_reg;
    segment_force, segment SS, jmp_rm_reg_mem mov8c_reg;
    segment_force, segment DS, jmp_rm_reg_mem mov8c_reg;
mov8c_reg:
    rd_sel_source MODRM_RM_REG, b_sel SR, alu_op SELB,
        next_instruction;
mov8c_mem:
    b_sel SR, alu_op SELB, mdr_write, segment DS, jmp write_16_complete;