Bochs/bochs/cpu/arith8.cc
Stanislav Shwartsman f5d55f5eb6 - Implemented Task Switch intercept in SVM, cleanup in task switch handling code
- Changed (c) year in several cpu files
- Cleanup and indent fixes in VMX code
2012-01-11 20:21:29 +00:00

592 lines
15 KiB
C++

/////////////////////////////////////////////////////////////////////////
// $Id$
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2001-2012 The Bochs Project
//
// 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., 51 Franklin St, Fifth Floor, Boston, MA B 02110-1301 USA
/////////////////////////////////////////////////////////////////////////
#define NEED_CPU_REG_SHORTCUTS 1
#include "bochs.h"
#include "cpu.h"
#define LOG_THIS BX_CPU_THIS_PTR
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADD_EbGbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u op2 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u sum = op1 + op2;
write_RMW_virtual_byte(sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADD_GbEbR(bxInstruction_c *i)
{
Bit32u op1 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u sum = op1 + op2;
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADD_GbEbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2 = read_virtual_byte(i->seg(), eaddr);
Bit32u sum = op1 + op2;
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADD_ALIb(bxInstruction_c *i)
{
Bit32u op1 = AL;
Bit32u op2 = i->Ib();
Bit32u sum = op1 + op2;
AL = sum;
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADC_EbGbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u op2 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u sum = op1 + op2 + getB_CF();
write_RMW_virtual_byte(sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADC_GbEbR(bxInstruction_c *i)
{
Bit32u op1 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u sum = op1 + op2 + getB_CF();
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADC_GbEbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2 = read_virtual_byte(i->seg(), eaddr);
Bit32u sum = op1 + op2 + getB_CF();
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADC_ALIb(bxInstruction_c *i)
{
Bit32u op1 = AL;
Bit32u op2 = i->Ib();
Bit32u sum = op1 + op2 + getB_CF();
AL = sum;
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SBB_EbGbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u op2_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u diff_8 = op1_8 - (op2_8 + getB_CF());
write_RMW_virtual_byte(diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SBB_GbEbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u diff_8 = op1_8 - (op2_8 + getB_CF());
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SBB_GbEbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2_8 = read_virtual_byte(i->seg(), eaddr);
Bit32u diff_8 = op1_8 - (op2_8 + getB_CF());
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SBB_ALIb(bxInstruction_c *i)
{
Bit32u op1_8 = AL;
Bit32u op2_8 = i->Ib();
Bit32u diff_8 = op1_8 - (op2_8 + getB_CF());
AL = diff_8;
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SBB_EbIbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u op2_8 = i->Ib();
Bit32u diff_8 = op1_8 - (op2_8 + getB_CF());
write_RMW_virtual_byte(diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SBB_EbIbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u op2_8 = i->Ib();
Bit32u diff_8 = op1_8 - (op2_8 + getB_CF());
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SUB_EbGbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u op2_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u diff_8 = op1_8 - op2_8;
write_RMW_virtual_byte(diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SUB_GbEbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u diff_8 = op1_8 - op2_8;
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SUB_GbEbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2_8 = read_virtual_byte(i->seg(), eaddr);
Bit32u diff_8 = op1_8 - op2_8;
BX_WRITE_8BIT_REGx(i->nnn(), i->extend8bitL(), diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SUB_ALIb(bxInstruction_c *i)
{
Bit32u op1_8 = AL;
Bit32u op2_8 = i->Ib();
Bit32u diff_8 = op1_8 - op2_8;
AL = diff_8;
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::CMP_EbGbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = read_virtual_byte(i->seg(), eaddr);
Bit32u op2_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u diff_8 = op1_8 - op2_8;
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::CMP_GbEbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u diff_8 = op1_8 - op2_8;
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::CMP_GbEbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u op2_8 = read_virtual_byte(i->seg(), eaddr);
Bit32u diff_8 = op1_8 - op2_8;
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::CMP_ALIb(bxInstruction_c *i)
{
Bit32u op1_8 = AL;
Bit32u op2_8 = i->Ib();
Bit32u diff_8 = op1_8 - op2_8;
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::XADD_EbGbM(bxInstruction_c *i)
{
/* XADD dst(r/m8), src(r8)
* temp <-- src + dst | sum = op2 + op1
* src <-- dst | op2 = op1
* dst <-- tmp | op1 = sum
*/
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u op2 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u 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_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::XADD_EbGbR(bxInstruction_c *i)
{
/* XADD dst(r/m8), src(r8)
* temp <-- src + dst | sum = op2 + op1
* src <-- dst | op2 = op1
* dst <-- tmp | op1 = sum
*/
Bit32u op1 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u op2 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
Bit32u 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);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADD_EbIbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u op2 = i->Ib();
Bit32u sum = op1 + op2;
write_RMW_virtual_byte(sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADD_EbIbR(bxInstruction_c *i)
{
Bit32u op1 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u op2 = i->Ib();
Bit32u sum = op1 + op2;
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADC_EbIbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u op2 = i->Ib();
Bit32u sum = op1 + op2 + getB_CF();
write_RMW_virtual_byte(sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ADC_EbIbR(bxInstruction_c *i)
{
Bit32u op1 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u op2 = i->Ib();
Bit32u sum = op1 + op2 + getB_CF();
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
SET_FLAGS_OSZAPC_ADD_8(op1, op2, sum);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SUB_EbIbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u op2_8 = i->Ib();
Bit32u diff_8 = op1_8 - op2_8;
write_RMW_virtual_byte(diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SUB_EbIbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u op2_8 = i->Ib();
Bit32u diff_8 = op1_8 - op2_8;
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::CMP_EbIbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = read_virtual_byte(i->seg(), eaddr);
Bit32u op2_8 = i->Ib();
Bit32u diff_8 = op1_8 - op2_8;
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::CMP_EbIbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u op2_8 = i->Ib();
Bit32u diff_8 = op1_8 - op2_8;
SET_FLAGS_OSZAPC_SUB_8(op1_8, op2_8, diff_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr);
op1_8 = - (Bit8s)(op1_8);
write_RMW_virtual_byte(op1_8);
SET_FLAGS_OSZAPC_SUB_8(0, 0 - op1_8, op1_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::NEG_EbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
op1_8 = - (Bit8s)(op1_8);
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op1_8);
SET_FLAGS_OSZAPC_SUB_8(0, 0 - op1_8, op1_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::INC_EbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr);
op1_8++;
write_RMW_virtual_byte(op1_8);
SET_FLAGS_OSZAP_ADD_8(op1_8 - 1, 0, op1_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::INC_EbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
op1_8++;
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op1_8);
SET_FLAGS_OSZAP_ADD_8(op1_8 - 1, 0, op1_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::DEC_EbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr);
op1_8--;
write_RMW_virtual_byte(op1_8);
SET_FLAGS_OSZAP_SUB_8(op1_8 + 1, 0, op1_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::DEC_EbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
op1_8--;
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op1_8);
SET_FLAGS_OSZAP_SUB_8(op1_8 + 1, 0, op1_8);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::CMPXCHG_EbGbM(bxInstruction_c *i)
{
bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i));
Bit32u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr);
Bit32u diff_8 = AL - op1_8;
SET_FLAGS_OSZAPC_SUB_8(AL, op1_8, diff_8);
if (diff_8 == 0) { // if accumulator == dest
// dest <-- src
Bit32u op2_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
write_RMW_virtual_byte(op2_8);
}
else {
// accumulator <-- dest
AL = op1_8;
}
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::CMPXCHG_EbGbR(bxInstruction_c *i)
{
Bit32u op1_8 = BX_READ_8BIT_REGx(i->rm(), i->extend8bitL());
Bit32u diff_8 = AL - op1_8;
SET_FLAGS_OSZAPC_SUB_8(AL, op1_8, diff_8);
if (diff_8 == 0) { // if accumulator == dest
// dest <-- src
Bit32u op2_8 = BX_READ_8BIT_REGx(i->nnn(), i->extend8bitL());
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op2_8);
}
else {
// accumulator <-- dest
AL = op1_8;
}
BX_NEXT_INSTR(i);
}