mirror of https://github.com/bochs-emu/Bochs
810 lines
17 KiB
C++
810 lines
17 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::INC_RX(BxInstruction_t *i)
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{
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Bit16u rx;
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rx = ++ BX_CPU_THIS_PTR gen_reg[i->b1 & 0x07].word.rx;
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SET_FLAGS_OSZAP_16(0, 0, rx, BX_INSTR_INC16);
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}
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void
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BX_CPU_C::DEC_RX(BxInstruction_t *i)
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{
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Bit16u rx;
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rx = -- BX_CPU_THIS_PTR gen_reg[i->b1 & 0x07].word.rx;
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SET_FLAGS_OSZAP_16(0, 0, rx, BX_INSTR_DEC16);
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}
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void
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BX_CPU_C::ADD_EwGw(BxInstruction_t *i)
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{
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Bit16u op2_16, op1_16, sum_16;
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/* op2_16 is a register, i->rm_addr is an index of a register */
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op2_16 = BX_READ_16BIT_REG(i->nnn);
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/* op1_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op1_16);
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}
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sum_16 = op1_16 + op2_16;
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/* now write sum back to destination */
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if (i->mod == 0xc0) {
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BX_WRITE_16BIT_REG(i->rm, sum_16);
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}
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else {
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write_virtual_word(i->seg, i->rm_addr, &sum_16);
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}
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SET_FLAGS_OSZAPC_16(op1_16, op2_16, sum_16, BX_INSTR_ADD16);
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}
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void
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BX_CPU_C::ADD_GwEw(BxInstruction_t *i)
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{
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Bit16u op1_16, op2_16, sum_16;
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/* op1_16 is a register, i->rm_addr is an index of a register */
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op1_16 = BX_READ_16BIT_REG(i->nnn);
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/* op2_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op2_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op2_16);
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}
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sum_16 = op1_16 + op2_16;
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/* now write sum back to destination */
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BX_WRITE_16BIT_REG(i->nnn, sum_16);
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SET_FLAGS_OSZAPC_16(op1_16, op2_16, sum_16, BX_INSTR_ADD16);
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}
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void
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BX_CPU_C::ADD_AXIw(BxInstruction_t *i)
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{
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Bit16u op1_16, op2_16, sum_16;
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op1_16 = AX;
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op2_16 = i->Iw;
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sum_16 = op1_16 + op2_16;
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/* now write sum back to destination */
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AX = sum_16;
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SET_FLAGS_OSZAPC_16(op1_16, op2_16, sum_16, BX_INSTR_ADD16);
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}
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void
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BX_CPU_C::ADC_EwGw(BxInstruction_t *i)
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{
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Boolean temp_CF;
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Bit16u op2_16, op1_16, sum_16;
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temp_CF = get_CF();
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/* op2_16 is a register, i->rm_addr is an index of a register */
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op2_16 = BX_READ_16BIT_REG(i->nnn);
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/* op1_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op1_16);
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}
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sum_16 = op1_16 + op2_16 + 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_16BIT_REG(i->rm, sum_16);
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}
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else {
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write_RMW_virtual_word(sum_16);
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}
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SET_FLAGS_OSZAPC_16_CF(op1_16, op2_16, sum_16, BX_INSTR_ADC16,
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temp_CF);
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}
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void
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BX_CPU_C::ADC_GwEw(BxInstruction_t *i)
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{
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Boolean temp_CF;
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Bit16u op1_16, op2_16, sum_16;
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temp_CF = get_CF();
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/* op1_16 is a register, i->rm_addr is an index of a register */
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op1_16 = BX_READ_16BIT_REG(i->nnn);
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/* op2_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op2_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op2_16);
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}
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sum_16 = op1_16 + op2_16 + temp_CF;
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/* now write sum back to destination */
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BX_WRITE_16BIT_REG(i->nnn, sum_16);
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SET_FLAGS_OSZAPC_16_CF(op1_16, op2_16, sum_16, BX_INSTR_ADC16,
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temp_CF);
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}
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void
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BX_CPU_C::ADC_AXIw(BxInstruction_t *i)
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{
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Boolean temp_CF;
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Bit16u op1_16, op2_16, sum_16;
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temp_CF = get_CF();
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op1_16 = AX;
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op2_16 = i->Iw;
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sum_16 = op1_16 + op2_16 + temp_CF;
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/* now write sum back to destination */
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AX = sum_16;
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SET_FLAGS_OSZAPC_16_CF(op1_16, op2_16, sum_16, BX_INSTR_ADC16,
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temp_CF);
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}
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void
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BX_CPU_C::SBB_EwGw(BxInstruction_t *i)
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{
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Boolean temp_CF;
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Bit16u op2_16, op1_16, diff_16;
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temp_CF = get_CF();
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/* op2_16 is a register, i->rm_addr is an index of a register */
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op2_16 = BX_READ_16BIT_REG(i->nnn);
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/* op1_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op1_16);
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}
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diff_16 = op1_16 - (op2_16 + 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_16BIT_REG(i->rm, diff_16);
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}
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else {
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write_RMW_virtual_word(diff_16);
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}
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SET_FLAGS_OSZAPC_16_CF(op1_16, op2_16, diff_16, BX_INSTR_SBB16,
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temp_CF);
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}
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void
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BX_CPU_C::SBB_GwEw(BxInstruction_t *i)
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{
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Boolean temp_CF;
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temp_CF = get_CF();
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Bit16u op1_16, op2_16, diff_16;
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/* op1_16 is a register, i->rm_addr is an index of a register */
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op1_16 = BX_READ_16BIT_REG(i->nnn);
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/* op2_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op2_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op2_16);
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}
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diff_16 = op1_16 - (op2_16 + temp_CF);
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/* now write diff back to destination */
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BX_WRITE_16BIT_REG(i->nnn, diff_16);
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SET_FLAGS_OSZAPC_16_CF(op1_16, op2_16, diff_16, BX_INSTR_SBB16,
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temp_CF);
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}
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void
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BX_CPU_C::SBB_AXIw(BxInstruction_t *i)
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{
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Boolean temp_CF;
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Bit16u op1_16, op2_16, diff_16;
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temp_CF = get_CF();
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op1_16 = AX;
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op2_16 = i->Iw;
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diff_16 = op1_16 - (op2_16 + temp_CF);
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/* now write diff back to destination */
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AX = diff_16;
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SET_FLAGS_OSZAPC_16_CF(op1_16, op2_16, diff_16, BX_INSTR_SBB16,
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temp_CF);
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}
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void
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BX_CPU_C::SBB_EwIw(BxInstruction_t *i)
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{
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Boolean temp_CF;
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Bit16u op2_16, op1_16, diff_16;
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temp_CF = get_CF();
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op2_16 = i->Iw;
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/* op1_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op1_16);
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}
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diff_16 = op1_16 - (op2_16 + 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_16BIT_REG(i->rm, diff_16);
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}
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else {
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write_RMW_virtual_word(diff_16);
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}
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SET_FLAGS_OSZAPC_16_CF(op1_16, op2_16, diff_16, BX_INSTR_SBB16,
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temp_CF);
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}
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void
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BX_CPU_C::SUB_EwGw(BxInstruction_t *i)
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{
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Bit16u op2_16, op1_16, diff_16;
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/* op2_16 is a register, i->rm_addr is an index of a register */
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op2_16 = BX_READ_16BIT_REG(i->nnn);
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/* op1_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op1_16);
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}
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diff_16 = op1_16 - op2_16;
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/* now write diff back to destination */
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if (i->mod == 0xc0) {
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BX_WRITE_16BIT_REG(i->rm, diff_16);
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}
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else {
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write_RMW_virtual_word(diff_16);
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}
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SET_FLAGS_OSZAPC_16(op1_16, op2_16, diff_16, BX_INSTR_SUB16);
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}
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void
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BX_CPU_C::SUB_GwEw(BxInstruction_t *i)
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{
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Bit16u op1_16, op2_16, diff_16;
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/* op1_16 is a register, i->rm_addr is an index of a register */
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op1_16 = BX_READ_16BIT_REG(i->nnn);
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/* op2_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op2_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op2_16);
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}
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diff_16 = op1_16 - op2_16;
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/* now write diff back to destination */
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BX_WRITE_16BIT_REG(i->nnn, diff_16);
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SET_FLAGS_OSZAPC_16(op1_16, op2_16, diff_16, BX_INSTR_SUB16);
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}
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void
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BX_CPU_C::SUB_AXIw(BxInstruction_t *i)
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{
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Bit16u op1_16, op2_16, diff_16;
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op1_16 = AX;
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op2_16 = i->Iw;
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diff_16 = op1_16 - op2_16;
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/* now write diff back to destination */
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AX = diff_16;
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SET_FLAGS_OSZAPC_16(op1_16, op2_16, diff_16, BX_INSTR_SUB16);
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}
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void
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BX_CPU_C::CMP_EwGw(BxInstruction_t *i)
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{
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Bit16u op2_16, op1_16, diff_16;
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/* op2_16 is a register, i->rm_addr is an index of a register */
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op2_16 = BX_READ_16BIT_REG(i->nnn);
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/* op1_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op1_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op1_16);
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}
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diff_16 = op1_16 - op2_16;
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SET_FLAGS_OSZAPC_16(op1_16, op2_16, diff_16, BX_INSTR_CMP16);
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}
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void
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BX_CPU_C::CMP_GwEw(BxInstruction_t *i)
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{
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Bit16u op1_16, op2_16, diff_16;
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/* op1_16 is a register, i->rm_addr is an index of a register */
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op1_16 = BX_READ_16BIT_REG(i->nnn);
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/* op2_16 is a register or memory reference */
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if (i->mod == 0xc0) {
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op2_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op2_16);
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}
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diff_16 = op1_16 - op2_16;
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SET_FLAGS_OSZAPC_16(op1_16, op2_16, diff_16, BX_INSTR_CMP16);
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}
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void
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BX_CPU_C::CMP_AXIw(BxInstruction_t *i)
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{
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Bit16u op1_16, op2_16, diff_16;
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op1_16 = AX;
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op2_16 = i->Iw;
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diff_16 = op1_16 - op2_16;
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SET_FLAGS_OSZAPC_16(op1_16, op2_16, diff_16, BX_INSTR_CMP16);
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}
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void
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BX_CPU_C::CBW(BxInstruction_t *i)
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{
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/* CBW: no flags are effected */
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AX = (Bit8s) AL;
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}
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void
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BX_CPU_C::CWD(BxInstruction_t *i)
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{
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/* CWD: no flags are affected */
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if (AX & 0x8000) {
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DX = 0xFFFF;
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}
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else {
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DX = 0x0000;
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}
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}
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void
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BX_CPU_C::XADD_EwGw(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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Bit16u op2_16, op1_16, sum_16;
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/* XADD dst(r/m), src(r)
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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_16 = BX_READ_16BIT_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_16 = BX_READ_16BIT_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_word(i->seg, i->rm_addr, &op1_16);
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}
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sum_16 = op1_16 + op2_16;
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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
|
|
// should be the sum, as op1 & op2 may be the same register.
|
|
// For example: XADD AL, AL
|
|
BX_WRITE_16BIT_REG(i->nnn, op1_16);
|
|
BX_WRITE_16BIT_REG(i->rm, sum_16);
|
|
}
|
|
else {
|
|
write_RMW_virtual_word(sum_16);
|
|
/* and write destination into source */
|
|
BX_WRITE_16BIT_REG(i->nnn, op1_16);
|
|
}
|
|
|
|
|
|
SET_FLAGS_OSZAPC_16(op1_16, op2_16, sum_16, BX_INSTR_XADD16);
|
|
#else
|
|
bx_panic("XADD_EvGv: not supported on < 80486\n");
|
|
#endif
|
|
}
|
|
|
|
|
|
|
|
void
|
|
BX_CPU_C::ADD_EwIw(BxInstruction_t *i)
|
|
{
|
|
Bit16u op2_16, op1_16, sum_16;
|
|
|
|
|
|
op2_16 = i->Iw;
|
|
|
|
/* op1_16 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_16 = BX_READ_16BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_word(i->seg, i->rm_addr, &op1_16);
|
|
}
|
|
|
|
sum_16 = op1_16 + op2_16;
|
|
|
|
/* now write sum back to destination */
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_16BIT_REG(i->rm, sum_16);
|
|
}
|
|
else {
|
|
write_RMW_virtual_word(sum_16);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_16(op1_16, op2_16, sum_16, BX_INSTR_ADD16);
|
|
}
|
|
|
|
void
|
|
BX_CPU_C::ADC_EwIw(BxInstruction_t *i)
|
|
{
|
|
Boolean temp_CF;
|
|
Bit16u op2_16, op1_16, sum_16;
|
|
|
|
temp_CF = get_CF();
|
|
|
|
|
|
op2_16 = i->Iw;
|
|
|
|
/* op1_16 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_16 = BX_READ_16BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_word(i->seg, i->rm_addr, &op1_16);
|
|
}
|
|
|
|
sum_16 = op1_16 + op2_16 + temp_CF;
|
|
|
|
/* now write sum back to destination */
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_16BIT_REG(i->rm, sum_16);
|
|
}
|
|
else {
|
|
write_RMW_virtual_word(sum_16);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_16_CF(op1_16, op2_16, sum_16, BX_INSTR_ADC16,
|
|
temp_CF);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::SUB_EwIw(BxInstruction_t *i)
|
|
{
|
|
Bit16u op2_16, op1_16, diff_16;
|
|
|
|
|
|
op2_16 = i->Iw;
|
|
|
|
/* op1_16 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_16 = BX_READ_16BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_word(i->seg, i->rm_addr, &op1_16);
|
|
}
|
|
|
|
diff_16 = op1_16 - op2_16;
|
|
|
|
/* now write diff back to destination */
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_16BIT_REG(i->rm, diff_16);
|
|
}
|
|
else {
|
|
write_RMW_virtual_word(diff_16);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_16(op1_16, op2_16, diff_16, BX_INSTR_SUB16);
|
|
}
|
|
|
|
void
|
|
BX_CPU_C::CMP_EwIw(BxInstruction_t *i)
|
|
{
|
|
Bit16u op2_16, op1_16, diff_16;
|
|
|
|
|
|
op2_16 = i->Iw;
|
|
|
|
/* op1_16 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_16 = BX_READ_16BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_virtual_word(i->seg, i->rm_addr, &op1_16);
|
|
}
|
|
|
|
diff_16 = op1_16 - op2_16;
|
|
|
|
SET_FLAGS_OSZAPC_16(op1_16, op2_16, diff_16, BX_INSTR_CMP16);
|
|
}
|
|
|
|
|
|
|
|
void
|
|
BX_CPU_C::NEG_Ew(BxInstruction_t *i)
|
|
{
|
|
Bit16u op1_16, diff_16;
|
|
|
|
|
|
/* op1_16 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_16 = BX_READ_16BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_word(i->seg, i->rm_addr, &op1_16);
|
|
}
|
|
|
|
diff_16 = 0 - op1_16;
|
|
|
|
/* now write diff back to destination */
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_16BIT_REG(i->rm, diff_16);
|
|
}
|
|
else {
|
|
write_RMW_virtual_word(diff_16);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_16(op1_16, 0, diff_16, BX_INSTR_NEG16);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::INC_Ew(BxInstruction_t *i)
|
|
{
|
|
Bit16u op1_16;
|
|
|
|
/* op1_16 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_16 = BX_READ_16BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_word(i->seg, i->rm_addr, &op1_16);
|
|
}
|
|
|
|
op1_16++;
|
|
|
|
/* now write sum back to destination */
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_16BIT_REG(i->rm, op1_16);
|
|
}
|
|
else {
|
|
write_RMW_virtual_word(op1_16);
|
|
}
|
|
|
|
SET_FLAGS_OSZAP_16(0, 0, op1_16, BX_INSTR_INC16);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::DEC_Ew(BxInstruction_t *i)
|
|
{
|
|
Bit16u op1_16;
|
|
|
|
/* op1_16 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_16 = BX_READ_16BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_word(i->seg, i->rm_addr, &op1_16);
|
|
}
|
|
|
|
op1_16--;
|
|
|
|
/* now write sum back to destination */
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_16BIT_REG(i->rm, op1_16);
|
|
}
|
|
else {
|
|
write_RMW_virtual_word(op1_16);
|
|
}
|
|
|
|
SET_FLAGS_OSZAP_16(0, 0, op1_16, BX_INSTR_DEC16);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::CMPXCHG_EwGw(BxInstruction_t *i)
|
|
{
|
|
#if (BX_CPU_LEVEL >= 4) || (BX_CPU_LEVEL_HACKED >= 4)
|
|
|
|
Bit16u op2_16, op1_16, diff_16;
|
|
|
|
/* op1_16 is a register or memory reference */
|
|
if (i->mod == 0xc0) {
|
|
op1_16 = BX_READ_16BIT_REG(i->rm);
|
|
}
|
|
else {
|
|
/* pointer, segment address pair */
|
|
read_RMW_virtual_word(i->seg, i->rm_addr, &op1_16);
|
|
}
|
|
|
|
diff_16 = AX - op1_16;
|
|
|
|
SET_FLAGS_OSZAPC_16(AX, op1_16, diff_16, BX_INSTR_CMP16);
|
|
|
|
if (diff_16 == 0) { // if accumulator == dest
|
|
// ZF = 1
|
|
set_ZF(1);
|
|
// dest <-- src
|
|
op2_16 = BX_READ_16BIT_REG(i->nnn);
|
|
|
|
if (i->mod == 0xc0) {
|
|
BX_WRITE_16BIT_REG(i->rm, op2_16);
|
|
}
|
|
else {
|
|
write_RMW_virtual_word(op2_16);
|
|
}
|
|
}
|
|
else {
|
|
// ZF = 0
|
|
set_ZF(0);
|
|
// accumulator <-- dest
|
|
AX = op1_16;
|
|
}
|
|
|
|
#else
|
|
bx_panic("CMPXCHG_EwGw:\n");
|
|
#endif
|
|
}
|