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/////////////////////////////////////////////////////////////////////////
// $Id$
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2001-2018 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
void BX_CPP_AttrRegparmN(1) BX_CPU_C::MUL_ALEbR(bxInstruction_c *i)
{
Bit8u op1 = AL;
Bit8u op2 = BX_READ_8BIT_REGx(i->src(), i->extend8bitL());
Bit32u product_16 = ((Bit16u) op1) * ((Bit16u) op2);
Bit8u product_8l = (product_16 & 0xFF);
Bit8u product_8h = product_16 >> 8;
/* now write product back to destination */
AX = product_16;
/* set EFLAGS */
SET_FLAGS_OSZAPC_LOGIC_8(product_8l);
if(product_8h != 0)
{
BX_CPU_THIS_PTR oszapc.assert_flags_OxxxxC();
}
BX_NEXT_INSTR(i);
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::IMUL_ALEbR(bxInstruction_c *i)
{
Bit8s op1 = AL;
Bit8s op2 = BX_READ_8BIT_REGx(i->src(), i->extend8bitL());
Bit16s product_16 = op1 * op2;
Bit8u product_8 = (product_16 & 0xFF);
/* now write product back to destination */
AX = product_16;
/* set EFLAGS:
* IMUL r/m8: condition for clearing CF & OF:
* AX = sign-extend of AL to 16 bits
*/
SET_FLAGS_OSZAPC_LOGIC_8(product_8);
if(product_16 != (Bit8s) product_16)
{
BX_CPU_THIS_PTR oszapc.assert_flags_OxxxxC();
}
BX_NEXT_INSTR(i);
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::DIV_ALEbR(bxInstruction_c *i)
{
Bit8u op2 = BX_READ_8BIT_REGx(i->src(), i->extend8bitL());
if (op2 == 0) {
exception(BX_DE_EXCEPTION, 0);
}
Bit16u op1 = AX;
Bit16u quotient_16 = op1 / op2;
Bit8u remainder_8 = op1 % op2;
Bit8u quotient_8l = quotient_16 & 0xFF;
if (quotient_16 != quotient_8l)
{
exception(BX_DE_EXCEPTION, 0);
}
/* now write quotient back to destination */
AL = quotient_8l;
AH = remainder_8;
BX_NEXT_INSTR(i);
}
void BX_CPP_AttrRegparmN(1) BX_CPU_C::IDIV_ALEbR(bxInstruction_c *i)
{
Bit16s op1 = AX;
/* check MIN_INT case */
if (op1 == ((Bit16s)0x8000))
exception(BX_DE_EXCEPTION, 0);
Bit8s op2 = BX_READ_8BIT_REGx(i->src(), i->extend8bitL());
if (op2 == 0)
exception(BX_DE_EXCEPTION, 0);
Bit16s quotient_16 = op1 / op2;
Bit8s remainder_8 = op1 % op2;
Bit8s quotient_8l = quotient_16 & 0xFF;
if (quotient_16 != quotient_8l)
exception(BX_DE_EXCEPTION, 0);
/* now write quotient back to destination */
AL = quotient_8l;
AH = remainder_8;
BX_NEXT_INSTR(i);
}
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