00c14e4efe
all available optimizations in one shot.
Finished one last case of an instruction which could but didn't use
the Read-Modify-Write variants of access.cc functions.
Started going through the integer instructions, merging obvious cases
where there are two "if (modrm==11b) {" clauses and very little
action in between, and cleaning up the aweful indentation leftover
from many years ago when those instructions were implemented using
cut-and-paste. We may get a little extra performance out of these
mods, but they'll also be easier after I'm finished to enhance
with asm() statements to knock out the lazy flags processing on x86.
684 lines
14 KiB
C++
684 lines
14 KiB
C++
/////////////////////////////////////////////////////////////////////////
|
|
// $Id: arith8.cc,v 1.19 2002-09-30 02:02:06 kevinlawton Exp $
|
|
/////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// Copyright (C) 2001 MandrakeSoft S.A.
|
|
//
|
|
// MandrakeSoft S.A.
|
|
// 43, rue d'Aboukir
|
|
// 75002 Paris - France
|
|
// http://www.linux-mandrake.com/
|
|
// http://www.mandrakesoft.com/
|
|
//
|
|
// This library is free software; you can redistribute it and/or
|
|
// modify it under the terms of the GNU Lesser General Public
|
|
// License as published by the Free Software Foundation; either
|
|
// version 2 of the License, or (at your option) any later version.
|
|
//
|
|
// This library 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
|
|
// Lesser General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Lesser General Public
|
|
// License along with this library; if not, write to the Free Software
|
|
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
|
|
|
|
|
|
|
|
|
|
#define NEED_CPU_REG_SHORTCUTS 1
|
|
#include "bochs.h"
|
|
#define LOG_THIS BX_CPU_THIS_PTR
|
|
|
|
|
|
|
|
|
|
|
|
void
|
|
BX_CPU_C::ADD_EbGb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op2, op1, sum;
|
|
|
|
op2 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
sum = op1 + op2;
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
|
|
sum = op1 + op2;
|
|
Write_RMW_virtual_byte(sum);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_8(op1, op2, sum, BX_INSTR_ADD8);
|
|
}
|
|
|
|
|
|
|
|
void
|
|
BX_CPU_C::ADD_GbEb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1, op2, sum;
|
|
|
|
op1 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op2 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
sum = op1 + op2;
|
|
}
|
|
else {
|
|
read_virtual_byte(i->seg(), RMAddr(i), &op2);
|
|
sum = op1 + op2;
|
|
}
|
|
|
|
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), sum);
|
|
|
|
SET_FLAGS_OSZAPC_8(op1, op2, sum, BX_INSTR_ADD8);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::ADD_ALIb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1, op2, sum;
|
|
|
|
|
|
op1 = AL;
|
|
op2 = i->Ib();
|
|
|
|
sum = op1 + op2;
|
|
|
|
AL = sum;
|
|
|
|
SET_FLAGS_OSZAPC_8(op1, op2, sum, BX_INSTR_ADD8);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::ADC_EbGb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op2, op1, sum;
|
|
Boolean temp_CF;
|
|
|
|
temp_CF = getB_CF();
|
|
|
|
op2 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
sum = op1 + op2 + temp_CF;
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
|
|
sum = op1 + op2 + temp_CF;
|
|
Write_RMW_virtual_byte(sum);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_8_CF(op1, op2, sum, BX_INSTR_ADC8, temp_CF);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::ADC_GbEb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1, op2, sum;
|
|
Boolean temp_CF;
|
|
|
|
temp_CF = getB_CF();
|
|
|
|
op1 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op2 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
}
|
|
else {
|
|
read_virtual_byte(i->seg(), RMAddr(i), &op2);
|
|
}
|
|
|
|
sum = op1 + op2 + temp_CF;
|
|
|
|
SET_FLAGS_OSZAPC_8_CF(op1, op2, sum, BX_INSTR_ADC8,
|
|
temp_CF);
|
|
|
|
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), sum);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::ADC_ALIb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1, op2, sum;
|
|
Boolean temp_CF;
|
|
|
|
temp_CF = getB_CF();
|
|
|
|
|
|
op1 = AL;
|
|
op2 = i->Ib();
|
|
|
|
sum = op1 + op2 + temp_CF;
|
|
|
|
AL = sum;
|
|
|
|
SET_FLAGS_OSZAPC_8_CF(op1, op2, sum, BX_INSTR_ADC8,
|
|
temp_CF);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::SBB_EbGb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op2_8, op1_8, diff_8;
|
|
Boolean temp_CF;
|
|
|
|
temp_CF = getB_CF();
|
|
|
|
|
|
op2_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
diff_8 = op1_8 - (op2_8 + temp_CF);
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
|
|
diff_8 = op1_8 - (op2_8 + temp_CF);
|
|
Write_RMW_virtual_byte(diff_8);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_8_CF(op1_8, op2_8, diff_8, BX_INSTR_SBB8,
|
|
temp_CF);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::SBB_GbEb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1_8, op2_8, diff_8;
|
|
Boolean temp_CF;
|
|
|
|
temp_CF = getB_CF();
|
|
|
|
op1_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op2_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
}
|
|
else {
|
|
read_virtual_byte(i->seg(), RMAddr(i), &op2_8);
|
|
}
|
|
|
|
diff_8 = op1_8 - (op2_8 + temp_CF);
|
|
|
|
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), diff_8);
|
|
|
|
SET_FLAGS_OSZAPC_8_CF(op1_8, op2_8, diff_8, BX_INSTR_SBB8,
|
|
temp_CF);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::SBB_ALIb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1_8, op2_8, diff_8;
|
|
Boolean temp_CF;
|
|
|
|
temp_CF = getB_CF();
|
|
|
|
op1_8 = AL;
|
|
op2_8 = i->Ib();
|
|
|
|
diff_8 = op1_8 - (op2_8 + temp_CF);
|
|
|
|
AL = diff_8;
|
|
|
|
SET_FLAGS_OSZAPC_8_CF(op1_8, op2_8, diff_8, BX_INSTR_SBB8,
|
|
temp_CF);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::SBB_EbIb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op2_8, op1_8, diff_8;
|
|
Boolean temp_CF;
|
|
|
|
temp_CF = getB_CF();
|
|
|
|
op2_8 = i->Ib();
|
|
|
|
if (i->modC0()) {
|
|
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
diff_8 = op1_8 - (op2_8 + temp_CF);
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
|
|
diff_8 = op1_8 - (op2_8 + temp_CF);
|
|
Write_RMW_virtual_byte(diff_8);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_8_CF(op1_8, op2_8, diff_8, BX_INSTR_SBB8,
|
|
temp_CF);
|
|
}
|
|
|
|
|
|
|
|
void
|
|
BX_CPU_C::SUB_EbGb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op2_8, op1_8, diff_8;
|
|
|
|
op2_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
diff_8 = op1_8 - op2_8;
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
|
|
diff_8 = op1_8 - op2_8;
|
|
Write_RMW_virtual_byte(diff_8);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_SUB8);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::SUB_GbEb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1_8, op2_8, diff_8;
|
|
|
|
op1_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op2_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
}
|
|
else {
|
|
read_virtual_byte(i->seg(), RMAddr(i), &op2_8);
|
|
}
|
|
|
|
diff_8 = op1_8 - op2_8;
|
|
|
|
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), diff_8);
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_SUB8);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::SUB_ALIb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1_8, op2_8, diff_8;
|
|
|
|
op1_8 = AL;
|
|
op2_8 = i->Ib();
|
|
|
|
diff_8 = op1_8 - op2_8;
|
|
|
|
AL = diff_8;
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_SUB8);
|
|
}
|
|
|
|
|
|
|
|
void
|
|
BX_CPU_C::CMP_EbGb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op2_8, op1_8;
|
|
|
|
op2_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
}
|
|
else {
|
|
read_virtual_byte(i->seg(), RMAddr(i), &op1_8);
|
|
}
|
|
|
|
#if (defined(__i386__) && defined(__GNUC__) && BX_SupportHostAsms)
|
|
Bit32u flags32;
|
|
asm (
|
|
"cmpb %2, %1\n\t"
|
|
"pushfl \n\t"
|
|
"popl %0"
|
|
: "=g" (flags32)
|
|
: "q" (op1_8), "mq" (op2_8)
|
|
: "cc"
|
|
);
|
|
BX_CPU_THIS_PTR eflags.val32 =
|
|
(BX_CPU_THIS_PTR eflags.val32 & ~EFlagsOSZAPCMask) | (flags32 & EFlagsOSZAPCMask);
|
|
BX_CPU_THIS_PTR lf_flags_status = 0;
|
|
#else
|
|
Bit8u diff_8;
|
|
diff_8 = op1_8 - op2_8;
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_CMP8);
|
|
#endif
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::CMP_GbEb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1_8, op2_8;
|
|
|
|
op1_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op2_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
}
|
|
else {
|
|
read_virtual_byte(i->seg(), RMAddr(i), &op2_8);
|
|
}
|
|
|
|
#if (defined(__i386__) && defined(__GNUC__) && BX_SupportHostAsms)
|
|
Bit32u flags32;
|
|
asm (
|
|
"cmpb %2, %1\n\t"
|
|
"pushfl \n\t"
|
|
"popl %0"
|
|
: "=g" (flags32)
|
|
: "q" (op1_8), "mq" (op2_8)
|
|
: "cc"
|
|
);
|
|
BX_CPU_THIS_PTR eflags.val32 =
|
|
(BX_CPU_THIS_PTR eflags.val32 & ~EFlagsOSZAPCMask) | (flags32 & EFlagsOSZAPCMask);
|
|
BX_CPU_THIS_PTR lf_flags_status = 0;
|
|
#else
|
|
Bit8u diff_8;
|
|
diff_8 = op1_8 - op2_8;
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_CMP8);
|
|
#endif
|
|
}
|
|
|
|
|
|
|
|
void
|
|
BX_CPU_C::CMP_ALIb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1_8, op2_8;
|
|
|
|
op1_8 = AL;
|
|
|
|
op2_8 = i->Ib();
|
|
|
|
#if (defined(__i386__) && defined(__GNUC__) && BX_SupportHostAsms)
|
|
Bit32u flags32;
|
|
asm (
|
|
"cmpb %2, %1\n\t"
|
|
"pushfl \n\t"
|
|
"popl %0"
|
|
: "=g" (flags32)
|
|
: "q" (op1_8), "mq" (op2_8)
|
|
: "cc"
|
|
);
|
|
BX_CPU_THIS_PTR eflags.val32 =
|
|
(BX_CPU_THIS_PTR eflags.val32 & ~EFlagsOSZAPCMask) | (flags32 & EFlagsOSZAPCMask);
|
|
BX_CPU_THIS_PTR lf_flags_status = 0;
|
|
#else
|
|
Bit8u diff_8;
|
|
diff_8 = op1_8 - op2_8;
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_CMP8);
|
|
#endif
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::XADD_EbGb(bxInstruction_c *i)
|
|
{
|
|
#if (BX_CPU_LEVEL >= 4) || (BX_CPU_LEVEL_HACKED >= 4)
|
|
|
|
Bit8u op2, op1, sum;
|
|
|
|
/* XADD dst(r/m8), src(r8)
|
|
* temp <-- src + dst | sum = op2 + op1
|
|
* src <-- dst | op2 = op1
|
|
* dst <-- tmp | op1 = sum
|
|
*/
|
|
|
|
op2 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
sum = op1 + op2;
|
|
// and write destination into source
|
|
// 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_8BIT_REGx(i->nnn(), i->extend8bitL(), op1);
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
|
|
sum = op1 + op2;
|
|
Write_RMW_virtual_byte(sum);
|
|
/* and write destination into source */
|
|
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), op1);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_8(op1, op2, sum, BX_INSTR_XADD8);
|
|
#else
|
|
BX_PANIC(("XADD_EbGb: not supported on < 80486"));
|
|
#endif
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::ADD_EbIb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op2, op1, sum;
|
|
|
|
op2 = i->Ib();
|
|
|
|
if (i->modC0()) {
|
|
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
sum = op1 + op2;
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
|
|
sum = op1 + op2;
|
|
Write_RMW_virtual_byte(sum);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_8(op1, op2, sum, BX_INSTR_ADD8);
|
|
}
|
|
|
|
void
|
|
BX_CPU_C::ADC_EbIb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op2, op1, sum;
|
|
Boolean temp_CF;
|
|
|
|
temp_CF = getB_CF();
|
|
|
|
op2 = i->Ib();
|
|
|
|
if (i->modC0()) {
|
|
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
sum = op1 + op2 + temp_CF;
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
|
|
sum = op1 + op2 + temp_CF;
|
|
Write_RMW_virtual_byte(sum);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_8_CF(op1, op2, sum, BX_INSTR_ADC8,
|
|
temp_CF);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::SUB_EbIb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op2_8, op1_8, diff_8;
|
|
|
|
op2_8 = i->Ib();
|
|
|
|
if (i->modC0()) {
|
|
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
diff_8 = op1_8 - op2_8;
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
|
|
diff_8 = op1_8 - op2_8;
|
|
Write_RMW_virtual_byte(diff_8);
|
|
}
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_SUB8);
|
|
}
|
|
|
|
void
|
|
BX_CPU_C::CMP_EbIb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op2_8, op1_8;
|
|
|
|
op2_8 = i->Ib();
|
|
|
|
if (i->modC0()) {
|
|
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
}
|
|
else {
|
|
read_virtual_byte(i->seg(), RMAddr(i), &op1_8);
|
|
}
|
|
|
|
#if (defined(__i386__) && defined(__GNUC__) && BX_SupportHostAsms)
|
|
Bit32u flags32;
|
|
asm (
|
|
"cmpb %2, %1\n\t"
|
|
"pushfl \n\t"
|
|
"popl %0"
|
|
: "=g" (flags32)
|
|
: "q" (op1_8), "mq" (op2_8)
|
|
: "cc"
|
|
);
|
|
BX_CPU_THIS_PTR eflags.val32 =
|
|
(BX_CPU_THIS_PTR eflags.val32 & ~EFlagsOSZAPCMask) | (flags32 & EFlagsOSZAPCMask);
|
|
BX_CPU_THIS_PTR lf_flags_status = 0;
|
|
#else
|
|
Bit8u diff_8;
|
|
diff_8 = op1_8 - op2_8;
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_CMP8);
|
|
#endif
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::NEG_Eb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1_8, diff_8;
|
|
|
|
if (i->modC0()) {
|
|
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
diff_8 = 0 - op1_8;
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
|
|
diff_8 = 0 - op1_8;
|
|
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_c *i)
|
|
{
|
|
Bit8u op1;
|
|
|
|
if (i->modC0()) {
|
|
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
op1++;
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op1);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
|
|
op1++;
|
|
Write_RMW_virtual_byte(op1);
|
|
}
|
|
|
|
SET_FLAGS_OSZAP_8(0, 0, op1, BX_INSTR_INC8);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::DEC_Eb(bxInstruction_c *i)
|
|
{
|
|
Bit8u op1_8;
|
|
|
|
if (i->modC0()) {
|
|
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
op1_8--;
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op1_8);
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
|
|
op1_8--;
|
|
Write_RMW_virtual_byte(op1_8);
|
|
}
|
|
|
|
SET_FLAGS_OSZAP_8(0, 0, op1_8, BX_INSTR_DEC8);
|
|
}
|
|
|
|
|
|
void
|
|
BX_CPU_C::CMPXCHG_EbGb(bxInstruction_c *i)
|
|
{
|
|
#if (BX_CPU_LEVEL >= 4) || (BX_CPU_LEVEL_HACKED >= 4)
|
|
Bit8u op2_8, op1_8, diff_8;
|
|
|
|
|
|
if (i->modC0()) {
|
|
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
|
|
}
|
|
else {
|
|
read_RMW_virtual_byte(i->seg(), RMAddr(i), &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_REGx(i->nnn(),i->extend8bitL());
|
|
|
|
if (i->modC0()) {
|
|
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), 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:"));
|
|
#endif
|
|
}
|