402d02974d
in cpu.cc out of the main loop, and into the asynchronous
events handling. I went through all the code paths, and
there doesn't seem to be any reason for that code to be
in the hot loop.
Added another accessor for getting instruction data, called
modC0(). A lot of instructions test whether the mod field
of mod-nnn-rm is 0xc0 or not, ie., it's a register operation
and not memory. So I flag this in fetchdecode{,64}.cc.
This added on the order of 1% performance improvement for
a Win95 boot.
Macroized a few leftover calls to Write_RMV_virtual_xyz()
that didn't get modified in the x86-64 merge. Really, they
just call the real function for now, but I want to have them
available to do direct writes with the guest2host TLB pointers.
768 lines
16 KiB
C++
768 lines
16 KiB
C++
/////////////////////////////////////////////////////////////////////////
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// $Id: arith8.cc,v 1.11 2002-09-20 03:52:58 kevinlawton Exp $
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/////////////////////////////////////////////////////////////////////////
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//
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// 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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#define NEED_CPU_REG_SHORTCUTS 1
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#include "bochs.h"
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#define LOG_THIS BX_CPU_THIS_PTR
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void
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BX_CPU_C::ADD_EbGb(bxInstruction_c *i)
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{
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Bit8u op2, op1, sum;
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/* op2 is a register, RMAddr(i) is an index of a register */
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op2 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op1 is a register or memory reference */
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if (i->modC0()) {
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op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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}
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else {
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read_RMW_virtual_byte(i->seg(), RMAddr(i), &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->modC0()) {
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BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), 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_c *i)
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{
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Bit8u op1, op2, sum;
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/* op1 is a register, RMAddr(i) is an index of a register */
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op1 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op2 is a register or memory reference */
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if (i->modC0()) {
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op2 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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_REGx(i->nnn(), i->extend8bitL(), 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_c *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_c *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, RMAddr(i) is an index of a register */
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op2 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op1 is a register or memory reference */
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if (i->modC0()) {
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op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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->modC0()) {
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BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), 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_c *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, RMAddr(i) is an index of a register */
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op1 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op2 is a register or memory reference */
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if (i->modC0()) {
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op2 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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_REGx(i->nnn(), i->extend8bitL(), sum);
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}
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void
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BX_CPU_C::ADC_ALIb(bxInstruction_c *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_c *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, RMAddr(i) is an index of a register */
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op2_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op1_8 is a register or memory reference */
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if (i->modC0()) {
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op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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->modC0()) {
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BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), 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_c *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, RMAddr(i) is an index of a register */
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op1_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op2 is a register or memory reference */
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if (i->modC0()) {
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op2_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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_REGx(i->nnn(), i->extend8bitL(), 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_c *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_c *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->modC0()) {
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op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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->modC0()) {
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BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), 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_c *i)
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{
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Bit8u op2_8, op1_8, diff_8;
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/* op2 is a register, RMAddr(i) is an index of a register */
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op2_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op1_8 is a register or memory reference */
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if (i->modC0()) {
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op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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->modC0()) {
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BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), 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_c *i)
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{
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Bit8u op1_8, op2_8, diff_8;
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/* op1 is a register, RMAddr(i) is an index of a register */
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op1_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op2 is a register or memory reference */
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if (i->modC0()) {
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op2_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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_REGx(i->nnn(), i->extend8bitL(), 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_c *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_c *i)
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{
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Bit8u op2_8, op1_8, diff_8;
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/* op2 is a register, RMAddr(i) is an index of a register */
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op2_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op1_8 is a register or memory reference */
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if (i->modC0()) {
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op1_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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_c *i)
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{
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Bit8u op1_8, op2_8, diff_8;
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/* op1 is a register, RMAddr(i) is an index of a register */
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op1_8 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op2 is a register or memory reference */
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if (i->modC0()) {
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op2_8 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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_c *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_c *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, RMAddr(i) is an index of a register */
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op2 = BX_READ_8BIT_REGx(i->nnn(),i->extend8bitL());
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/* op1 is a register or memory reference */
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if (i->modC0()) {
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op1 = BX_READ_8BIT_REGx(i->rm(),i->extend8bitL());
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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(), RMAddr(i), &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->modC0()) {
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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_REGx(i->nnn(), i->extend8bitL(), op1);
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BX_WRITE_8BIT_REGx(i->rm(), i->extend8bitL(), 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_REGx(i->nnn(), i->extend8bitL(), op1);
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}
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|
|
|
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, 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_virtual_byte(i->seg(), RMAddr(i), &op1_8);
|
|
}
|
|
|
|
diff_8 = op1_8 - op2_8;
|
|
|
|
SET_FLAGS_OSZAPC_8(op1_8, op2_8, diff_8, BX_INSTR_CMP8);
|
|
}
|
|
|
|
|
|
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
|
|
}
|