mirror of https://github.com/bochs-emu/Bochs
762 lines
15 KiB
C++
762 lines
15 KiB
C++
// Copyright (C) 2001 MandrakeSoft S.A.
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//
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// MandrakeSoft S.A.
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// 43, rue d'Aboukir
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// 75002 Paris - France
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// http://www.linux-mandrake.com/
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// http://www.mandrakesoft.com/
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//
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// This library is free software; you can redistribute it and/or
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// modify it under the terms of the GNU Lesser General Public
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// License as published by the Free Software Foundation; either
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// version 2 of the License, or (at your option) any later version.
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//
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public
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// License along with this library; if not, write to the Free Software
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// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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#include "bochs.h"
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void
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BX_CPU_C::ADD_EbGb(BxInstruction_t *i)
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{
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Bit8u op2, op1, sum;
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/* op2 is a register, i->rm_addr is an index of a register */
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op2 = BX_READ_8BIT_REG(i->nnn);
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/* op1 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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read_RMW_virtual_byte(i->seg, i->rm_addr, &op1);
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}
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sum = op1 + op2;
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/* now write sum back to destination */
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if (i->mod == 0xc0) {
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BX_WRITE_8BIT_REG(i->rm, sum);
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}
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else {
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write_RMW_virtual_byte(sum);
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}
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SET_FLAGS_OSZAPC_8(op1, op2, sum, BX_INSTR_ADD8);
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}
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void
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BX_CPU_C::ADD_GbEb(BxInstruction_t *i)
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{
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Bit8u op1, op2, sum;
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/* op1 is a register, i->rm_addr is an index of a register */
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op1 = BX_READ_8BIT_REG(i->nnn);
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/* op2 is a register or memory reference */
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if (i->mod == 0xc0) {
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op2 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_virtual_byte(i->seg, i->rm_addr, &op2);
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}
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sum = op1 + op2;
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/* now write sum back to destination, which is a register */
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BX_WRITE_8BIT_REG(i->nnn, sum);
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SET_FLAGS_OSZAPC_8(op1, op2, sum, BX_INSTR_ADD8);
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}
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void
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BX_CPU_C::ADD_ALIb(BxInstruction_t *i)
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{
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Bit8u op1, op2, sum;
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op1 = AL;
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op2 = i->Ib;
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sum = op1 + op2;
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/* now write sum back to destination, which is a register */
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AL = sum;
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SET_FLAGS_OSZAPC_8(op1, op2, sum, BX_INSTR_ADD8);
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}
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void
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BX_CPU_C::ADC_EbGb(BxInstruction_t *i)
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{
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Bit8u op2, op1, sum;
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Boolean temp_CF;
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temp_CF = get_CF();
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/* op2 is a register, i->rm_addr is an index of a register */
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op2 = BX_READ_8BIT_REG(i->nnn);
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/* op1 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_RMW_virtual_byte(i->seg, i->rm_addr, &op1);
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}
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sum = op1 + op2 + temp_CF;
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/* now write sum back to destination */
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if (i->mod == 0xc0) {
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BX_WRITE_8BIT_REG(i->rm, sum);
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}
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else {
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write_RMW_virtual_byte(sum);
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}
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SET_FLAGS_OSZAPC_8_CF(op1, op2, sum, BX_INSTR_ADC8, temp_CF);
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}
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void
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BX_CPU_C::ADC_GbEb(BxInstruction_t *i)
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{
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Bit8u op1, op2, sum;
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Boolean temp_CF;
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temp_CF = get_CF();
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/* op1 is a register, i->rm_addr is an index of a register */
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op1 = BX_READ_8BIT_REG(i->nnn);
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/* op2 is a register or memory reference */
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if (i->mod == 0xc0) {
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op2 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_virtual_byte(i->seg, i->rm_addr, &op2);
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}
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sum = op1 + op2 + temp_CF;
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SET_FLAGS_OSZAPC_8_CF(op1, op2, sum, BX_INSTR_ADC8,
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temp_CF);
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/* now write sum back to destination, which is a register */
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BX_WRITE_8BIT_REG(i->nnn, sum);
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}
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void
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BX_CPU_C::ADC_ALIb(BxInstruction_t *i)
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{
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Bit8u op1, op2, sum;
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Boolean temp_CF;
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temp_CF = get_CF();
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op1 = AL;
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op2 = i->Ib;
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sum = op1 + op2 + temp_CF;
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/* now write sum back to destination, which is a register */
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AL = sum;
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SET_FLAGS_OSZAPC_8_CF(op1, op2, sum, BX_INSTR_ADC8,
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temp_CF);
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}
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void
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BX_CPU_C::SBB_EbGb(BxInstruction_t *i)
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{
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Bit8u op2_8, op1_8, diff_8;
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Boolean temp_CF;
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temp_CF = get_CF();
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/* op2 is a register, i->rm_addr is an index of a register */
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op2_8 = BX_READ_8BIT_REG(i->nnn);
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/* op1_8 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1_8 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_RMW_virtual_byte(i->seg, i->rm_addr, &op1_8);
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}
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diff_8 = op1_8 - (op2_8 + temp_CF);
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/* now write diff back to destination */
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if (i->mod == 0xc0) {
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BX_WRITE_8BIT_REG(i->rm, diff_8);
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}
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else {
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write_RMW_virtual_byte(diff_8);
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}
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SET_FLAGS_OSZAPC_8_CF(op1_8, op2_8, diff_8, BX_INSTR_SBB8,
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temp_CF);
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}
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void
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BX_CPU_C::SBB_GbEb(BxInstruction_t *i)
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{
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Bit8u op1_8, op2_8, diff_8;
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Boolean temp_CF;
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temp_CF = get_CF();
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/* op1 is a register, i->rm_addr is an index of a register */
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op1_8 = BX_READ_8BIT_REG(i->nnn);
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/* op2 is a register or memory reference */
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if (i->mod == 0xc0) {
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op2_8 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_virtual_byte(i->seg, i->rm_addr, &op2_8);
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}
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diff_8 = op1_8 - (op2_8 + temp_CF);
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/* now write diff back to destination, which is a register */
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BX_WRITE_8BIT_REG(i->nnn, diff_8);
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SET_FLAGS_OSZAPC_8_CF(op1_8, op2_8, diff_8, BX_INSTR_SBB8,
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temp_CF);
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}
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void
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BX_CPU_C::SBB_ALIb(BxInstruction_t *i)
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{
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Bit8u op1_8, op2_8, diff_8;
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Boolean temp_CF;
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temp_CF = get_CF();
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op1_8 = AL;
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op2_8 = i->Ib;
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diff_8 = op1_8 - (op2_8 + temp_CF);
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/* now write diff back to destination, which is a register */
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AL = diff_8;
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SET_FLAGS_OSZAPC_8_CF(op1_8, op2_8, diff_8, BX_INSTR_SBB8,
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temp_CF);
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}
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void
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BX_CPU_C::SBB_EbIb(BxInstruction_t *i)
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{
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Bit8u op2_8, op1_8, diff_8;
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Boolean temp_CF;
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temp_CF = get_CF();
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op2_8 = i->Ib;
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/* op1_8 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1_8 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_RMW_virtual_byte(i->seg, i->rm_addr, &op1_8);
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}
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diff_8 = op1_8 - (op2_8 + temp_CF);
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/* now write diff back to destination */
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if (i->mod == 0xc0) {
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BX_WRITE_8BIT_REG(i->rm, diff_8);
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}
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else {
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write_RMW_virtual_byte(diff_8);
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}
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SET_FLAGS_OSZAPC_8_CF(op1_8, op2_8, diff_8, BX_INSTR_SBB8,
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temp_CF);
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}
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void
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BX_CPU_C::SUB_EbGb(BxInstruction_t *i)
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{
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Bit8u op2_8, op1_8, diff_8;
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/* op2 is a register, i->rm_addr is an index of a register */
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op2_8 = BX_READ_8BIT_REG(i->nnn);
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/* op1_8 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1_8 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_RMW_virtual_byte(i->seg, i->rm_addr, &op1_8);
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}
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diff_8 = op1_8 - op2_8;
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/* now write diff back to destination */
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if (i->mod == 0xc0) {
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BX_WRITE_8BIT_REG(i->rm, diff_8);
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}
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else {
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write_RMW_virtual_byte(diff_8);
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}
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SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_SUB8);
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}
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void
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BX_CPU_C::SUB_GbEb(BxInstruction_t *i)
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{
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Bit8u op1_8, op2_8, diff_8;
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/* op1 is a register, i->rm_addr is an index of a register */
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op1_8 = BX_READ_8BIT_REG(i->nnn);
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/* op2 is a register or memory reference */
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if (i->mod == 0xc0) {
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op2_8 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_virtual_byte(i->seg, i->rm_addr, &op2_8);
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}
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diff_8 = op1_8 - op2_8;
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/* now write diff back to destination, which is a register */
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BX_WRITE_8BIT_REG(i->nnn, diff_8);
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SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_SUB8);
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}
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void
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BX_CPU_C::SUB_ALIb(BxInstruction_t *i)
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{
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Bit8u op1_8, op2_8, diff_8;
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op1_8 = AL;
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op2_8 = i->Ib;
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diff_8 = op1_8 - op2_8;
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/* now write diff back to destination, which is a register */
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AL = diff_8;
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SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_SUB8);
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}
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void
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BX_CPU_C::CMP_EbGb(BxInstruction_t *i)
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{
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Bit8u op2_8, op1_8, diff_8;
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/* op2 is a register, i->rm_addr is an index of a register */
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op2_8 = BX_READ_8BIT_REG(i->nnn);
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/* op1_8 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1_8 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_virtual_byte(i->seg, i->rm_addr, &op1_8);
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}
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diff_8 = op1_8 - op2_8;
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SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_CMP8);
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}
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void
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BX_CPU_C::CMP_GbEb(BxInstruction_t *i)
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{
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Bit8u op1_8, op2_8, diff_8;
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/* op1 is a register, i->rm_addr is an index of a register */
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op1_8 = BX_READ_8BIT_REG(i->nnn);
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/* op2 is a register or memory reference */
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if (i->mod == 0xc0) {
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op2_8 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_virtual_byte(i->seg, i->rm_addr, &op2_8);
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}
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diff_8 = op1_8 - op2_8;
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SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_CMP8);
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}
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void
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BX_CPU_C::CMP_ALIb(BxInstruction_t *i)
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{
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Bit8u op1_8, op2_8, diff_8;
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op1_8 = AL;
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op2_8 = i->Ib;
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diff_8 = op1_8 - op2_8;
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SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_CMP8);
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}
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void
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BX_CPU_C::XADD_EbGb(BxInstruction_t *i)
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{
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#if (BX_CPU_LEVEL >= 4) || (BX_CPU_LEVEL_HACKED >= 4)
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Bit8u op2, op1, sum;
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/* XADD dst(r/m8), src(r8)
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* temp <-- src + dst | sum = op2 + op1
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* src <-- dst | op2 = op1
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* dst <-- tmp | op1 = sum
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*/
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/* op2 is a register, i->rm_addr is an index of a register */
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op2 = BX_READ_8BIT_REG(i->nnn);
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/* op1 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_RMW_virtual_byte(i->seg, i->rm_addr, &op1);
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}
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sum = op1 + op2;
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/* now write sum back to destination */
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if (i->mod == 0xc0) {
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// and write destination into source
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// Note: if both op1 & op2 are registers, the last one written
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// should be the sum, as op1 & op2 may be the same register.
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// For example: XADD AL, AL
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BX_WRITE_8BIT_REG(i->nnn, op1);
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BX_WRITE_8BIT_REG(i->rm, sum);
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}
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else {
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write_RMW_virtual_byte(sum);
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/* and write destination into source */
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BX_WRITE_8BIT_REG(i->nnn, op1);
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}
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SET_FLAGS_OSZAPC_8(op1, op2, sum, BX_INSTR_XADD8);
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#else
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bx_panic("XADD_EbGb: not supported on < 80486\n");
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#endif
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}
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void
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BX_CPU_C::ADD_EbIb(BxInstruction_t *i)
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{
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Bit8u op2, op1, sum;
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op2 = i->Ib;
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/* op1 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_RMW_virtual_byte(i->seg, i->rm_addr, &op1);
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}
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sum = op1 + op2;
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/* now write sum back to destination */
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if (i->mod == 0xc0) {
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BX_WRITE_8BIT_REG(i->rm, sum);
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}
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else {
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write_RMW_virtual_byte(sum);
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}
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SET_FLAGS_OSZAPC_8(op1, op2, sum, BX_INSTR_ADD8);
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}
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void
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BX_CPU_C::ADC_EbIb(BxInstruction_t *i)
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{
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Bit8u op2, op1, sum;
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Boolean temp_CF;
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temp_CF = get_CF();
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op2 = i->Ib;
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|
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/* op1 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1 = BX_READ_8BIT_REG(i->rm);
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}
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else {
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/* pointer, segment address pair */
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read_RMW_virtual_byte(i->seg, i->rm_addr, &op1);
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}
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sum = op1 + op2 + temp_CF;
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|
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/* now write sum back to destination */
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if (i->mod == 0xc0) {
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BX_WRITE_8BIT_REG(i->rm, sum);
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}
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else {
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write_RMW_virtual_byte(sum);
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}
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SET_FLAGS_OSZAPC_8_CF(op1, op2, sum, BX_INSTR_ADC8,
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temp_CF);
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}
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|
|
|
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void
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BX_CPU_C::SUB_EbIb(BxInstruction_t *i)
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{
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Bit8u op2_8, op1_8, diff_8;
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|
|
|
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op2_8 = i->Ib;
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|
|
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/* op1_8 is a register or memory reference */
|
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if (i->mod == 0xc0) {
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op1_8 = BX_READ_8BIT_REG(i->rm);
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}
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else {
|
|
/* pointer, segment address pair */
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read_RMW_virtual_byte(i->seg, i->rm_addr, &op1_8);
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}
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|
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diff_8 = op1_8 - op2_8;
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|
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|
/* now write diff back to destination */
|
|
if (i->mod == 0xc0) {
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BX_WRITE_8BIT_REG(i->rm, diff_8);
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|
}
|
|
else {
|
|
write_RMW_virtual_byte(diff_8);
|
|
}
|
|
|
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SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_SUB8);
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}
|
|
|
|
void
|
|
BX_CPU_C::CMP_EbIb(BxInstruction_t *i)
|
|
{
|
|
Bit8u op2_8, op1_8, diff_8;
|
|
|
|
op2_8 = i->Ib;
|
|
|
|
/* op1_8 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_8 = BX_READ_8BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_virtual_byte(i->seg, i->rm_addr, &op1_8);
|
|
}
|
|
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|
diff_8 = op1_8 - op2_8;
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_CMP8);
|
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}
|
|
|
|
|
|
void
|
|
BX_CPU_C::NEG_Eb(BxInstruction_t *i)
|
|
{
|
|
Bit8u op1_8, diff_8;
|
|
|
|
/* op1_8 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_8 = BX_READ_8BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_byte(i->seg, i->rm_addr, &op1_8);
|
|
}
|
|
|
|
diff_8 = 0 - op1_8;
|
|
|
|
/* now write diff back to destination */
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_8BIT_REG(i->rm, diff_8);
|
|
}
|
|
else {
|
|
write_RMW_virtual_byte(diff_8);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, 0, diff_8, BX_INSTR_NEG8);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::INC_Eb(BxInstruction_t *i)
|
|
{
|
|
Bit8u op1;
|
|
|
|
/* op1 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1 = BX_READ_8BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_byte(i->seg, i->rm_addr, &op1);
|
|
}
|
|
|
|
|
|
op1++;
|
|
|
|
/* now write sum back to destination */
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_8BIT_REG(i->rm, op1);
|
|
}
|
|
else {
|
|
write_RMW_virtual_byte(op1);
|
|
}
|
|
|
|
SET_FLAGS_OSZAP_8(0, 0, op1, BX_INSTR_INC8);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::DEC_Eb(BxInstruction_t *i)
|
|
{
|
|
Bit8u op1_8;
|
|
|
|
/* op1_8 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_8 = BX_READ_8BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_byte(i->seg, i->rm_addr, &op1_8);
|
|
}
|
|
|
|
op1_8--;
|
|
|
|
/* now write sum back to destination */
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_8BIT_REG(i->rm, op1_8);
|
|
}
|
|
else {
|
|
write_RMW_virtual_byte(op1_8);
|
|
}
|
|
|
|
SET_FLAGS_OSZAP_8(0, 0, op1_8, BX_INSTR_DEC8);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::CMPXCHG_EbGb(BxInstruction_t *i)
|
|
{
|
|
#if (BX_CPU_LEVEL >= 4) || (BX_CPU_LEVEL_HACKED >= 4)
|
|
Bit8u op2_8, op1_8, diff_8;
|
|
|
|
|
|
/* op1_8 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_8 = BX_READ_8BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_byte(i->seg, i->rm_addr, &op1_8);
|
|
}
|
|
|
|
diff_8 = AL - op1_8;
|
|
|
|
SET_FLAGS_OSZAPC_8(AL, op1_8, diff_8, BX_INSTR_CMP8);
|
|
|
|
if (diff_8 == 0) { // if accumulator == dest
|
|
// ZF = 1
|
|
set_ZF(1);
|
|
// dest <-- src
|
|
op2_8 = BX_READ_8BIT_REG(i->nnn);
|
|
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_8BIT_REG(i->rm, op2_8);
|
|
}
|
|
else {
|
|
write_RMW_virtual_byte(op2_8);
|
|
}
|
|
}
|
|
else {
|
|
// ZF = 0
|
|
set_ZF(0);
|
|
// accumulator <-- dest
|
|
AL = op1_8;
|
|
}
|
|
|
|
#else
|
|
bx_panic("CMPXCHG_EbGb:\n");
|
|
#endif
|
|
}
|