Bochs/bochs/cpu/arith8.cc
Kevin Lawton 91fd4b3745 Added new configure option --enable-host-specific-asms, so the
user can turn on/off use of native host specific inline asm
  statements.  By default, this option is enabled, so you only
  need it to disable inline asms in your compile for now.

Currently only on x86+GCC environments, will inline asm()
  statements be used.  Eventually, other platforms could specify
  some asm()s; probably for endian issues such as byte-swapping
  and unaligned memory accesses.  On x86, there are some inline
  asm()s which do the arithmetic EFLAGS processing so that the
  lazy flags handling is somewhat bypassed.  Eventually, I'll
  add more, at least for the more common instructions.  This
  adds a little extra performance.
2002-09-23 17:59:18 +00:00

822 lines
17 KiB
C++

/////////////////////////////////////////////////////////////////////////
// $Id: arith8.cc,v 1.16 2002-09-23 17:59:17 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 is a register, RMAddr(i) is an index of a register */
op2 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
/* op1 is a register or memory reference */
if (i->modC0()) {
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
}
sum = op1 + op2;
/* now write sum back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
}
else {
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 is a register, RMAddr(i) is an index of a register */
op1 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
/* op2 is a register or memory reference */
if (i->modC0()) {
op2 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_virtual_byte(i->seg(), RMAddr(i), &op2);
}
sum = op1 + op2;
/* now write sum back to destination, which is a register */
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;
/* now write sum back to destination, which is a register */
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 = !!get_CF();
/* op2 is a register, RMAddr(i) is an index of a register */
op2 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
/* op1 is a register or memory reference */
if (i->modC0()) {
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
}
sum = op1 + op2 + temp_CF;
/* now write sum back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
}
else {
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 = !!get_CF();
/* op1 is a register, RMAddr(i) is an index of a register */
op1 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
/* op2 is a register or memory reference */
if (i->modC0()) {
op2 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
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);
/* now write sum back to destination, which is a register */
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 = !!get_CF();
op1 = AL;
op2 = i->Ib();
sum = op1 + op2 + temp_CF;
/* now write sum back to destination, which is a register */
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 = !!get_CF();
/* op2 is a register, RMAddr(i) is an index of a register */
op2_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
/* op1_8 is a register or memory reference */
if (i->modC0()) {
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
}
diff_8 = op1_8 - (op2_8 + temp_CF);
/* now write diff back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
}
else {
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 = !!get_CF();
/* op1 is a register, RMAddr(i) is an index of a register */
op1_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
/* op2 is a register or memory reference */
if (i->modC0()) {
op2_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_virtual_byte(i->seg(), RMAddr(i), &op2_8);
}
diff_8 = op1_8 - (op2_8 + temp_CF);
/* now write diff back to destination, which is a register */
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 = !!get_CF();
op1_8 = AL;
op2_8 = i->Ib();
diff_8 = op1_8 - (op2_8 + temp_CF);
/* now write diff back to destination, which is a register */
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 = !!get_CF();
op2_8 = i->Ib();
/* op1_8 is a register or memory reference */
if (i->modC0()) {
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
}
diff_8 = op1_8 - (op2_8 + temp_CF);
/* now write diff back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
}
else {
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 is a register, RMAddr(i) is an index of a register */
op2_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
/* op1_8 is a register or memory reference */
if (i->modC0()) {
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
}
diff_8 = op1_8 - op2_8;
/* now write diff back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
}
else {
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 is a register, RMAddr(i) is an index of a register */
op1_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
/* op2 is a register or memory reference */
if (i->modC0()) {
op2_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_virtual_byte(i->seg(), RMAddr(i), &op2_8);
}
diff_8 = op1_8 - op2_8;
/* now write diff back to destination, which is a register */
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;
/* now write diff back to destination, which is a register */
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 & ~0x000008d5) | (flags32 & 0x000008d5);
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 & ~0x000008d5) | (flags32 & 0x000008d5);
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 & ~0x000008d5) | (flags32 & 0x000008d5);
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 is a register, RMAddr(i) is an index of a register */
op2 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
/* op1 is a register or memory reference */
if (i->modC0()) {
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
}
sum = op1 + op2;
/* now write sum back to destination */
if (i->modC0()) {
// 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 {
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();
/* op1 is a register or memory reference */
if (i->modC0()) {
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
}
sum = op1 + op2;
/* now write sum back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
}
else {
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 = !!get_CF();
op2 = i->Ib();
/* op1 is a register or memory reference */
if (i->modC0()) {
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
}
sum = op1 + op2 + temp_CF;
/* now write sum back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), sum);
}
else {
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();
/* op1_8 is a register or memory reference */
if (i->modC0()) {
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
}
diff_8 = op1_8 - op2_8;
/* now write diff back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), diff_8);
}
else {
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 & ~0x000008d5) | (flags32 & 0x000008d5);
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;
/* op1_8 is a register or memory reference */
if (i->modC0()) {
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
}
diff_8 = 0 - op1_8;
/* now write diff back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), 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_c *i)
{
Bit8u op1;
/* op1 is a register or memory reference */
if (i->modC0()) {
op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1);
}
op1++;
/* now write sum back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), op1);
}
else {
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;
/* op1_8 is a register or memory reference */
if (i->modC0()) {
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
read_RMW_virtual_byte(i->seg(), RMAddr(i), &op1_8);
}
op1_8--;
/* now write sum back to destination */
if (i->modC0()) {
BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), 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_c *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->modC0()) {
op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
}
else {
/* pointer, segment address pair */
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
}