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/*
* plex86: run multiple x86 operating systems concurrently
* Copyright (C) 1999-2001 Kevin P. Lawton
*
* mult16.c: emulation of 16-bit multiplication instructions
*
* 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
*/
#include "plex86.h"
#include "monitor.h"
void
IMUL_GwEwIw(vm_t *vm)
{
Bit16s op2, op3, product;
Bit32u eflags, arithmetic_eflags;
op3 = vm->i.Iw;
if (vm->i.mod == 0xc0) {
op2 = ReadReg16(vm, vm->i.rm);
}
else {
read_virtual_word(vm, vm->i.seg, vm->i.rm_addr, &op2);
}
arithmetic_eflags = read_eflags(vm) & 0x000008d5;
eflags = 0; /* keep compiler quiet */
asm volatile (
/* First copy guest arithmetic flags to monitor flags */
"pushfl \n\t" /* Get mon flags */
"popl %0 \n\t"
"andl $0xfffff700, %0 \n\t" /* Erase mon arithmetic flags */
"orl %5, %0 \n\t" /* Or in guest arithmetic flags */
"pushl %0 \n\t" /* Set flags in mon */
"popfl \n\t"
"imulw %4, %3 \n\t"
"pushfl \n\t"
"popl %0"
: "=r" (eflags), "=r" (product)
: "0" (eflags), "1" (op2), "g" (op3), "g" (arithmetic_eflags)
: "memory", "cc"
);
/* now write product back to destination */
WriteReg16(vm, vm->i.nnn, product);
SetOSZAPC(vm, eflags);
}
void
IMUL_GwEw(vm_t *vm)
{
Bit16s op1, op2, product;
Bit32u eflags, arithmetic_eflags;
op1 = ReadReg16(vm, vm->i.nnn);
if (vm->i.mod == 0xc0) {
op2 = ReadReg16(vm, vm->i.rm);
}
else {
read_virtual_word(vm, vm->i.seg, vm->i.rm_addr, &op2);
}
arithmetic_eflags = read_eflags(vm) & 0x000008d5;
eflags = 0; /* keep compiler quiet */
asm volatile (
/* First copy guest arithmetic flags to monitor flags */
"pushfl \n\t" /* Get mon flags */
"popl %0 \n\t"
"andl $0xfffff700, %0 \n\t" /* Erase mon arithmetic flags */
"orl %5, %0 \n\t" /* Or in guest arithmetic flags */
"pushl %0 \n\t" /* Set flags in mon */
"popfl \n\t"
"imulw %4, %3 \n\t"
"pushfl \n\t"
"popl %0"
: "=r" (eflags), "=r" (product)
: "0" (eflags), "1" (op1), "g" (op2), "g" (arithmetic_eflags)
: "memory", "cc"
);
/* now write product back to destination */
WriteReg16(vm, vm->i.nnn, product);
SetOSZAPC(vm, eflags);
}
void
MUL_AXEw(vm_t *vm)
{
Bit16s op2, ax, dx;
Bit32u eflags, arithmetic_eflags;
ax = G_AX(vm);
if (vm->i.mod == 0xc0) {
op2 = ReadReg16(vm, vm->i.rm);
}
else {
read_virtual_word(vm, vm->i.seg, vm->i.rm_addr, &op2);
}
arithmetic_eflags = read_eflags(vm) & 0x000008d5;
eflags = 0; /* keep compiler quiet */
asm volatile (
/* First copy guest arithmetic flags to monitor flags */
"pushfl \n\t" /* Get mon flags */
"popl %0 \n\t"
"andl $0xfffff700, %0 \n\t" /* Erase mon arithmetic flags */
"orl %6, %0 \n\t" /* Or in guest arithmetic flags */
"pushl %0 \n\t" /* Set flags in mon */
"popfl \n\t"
"mulw %5 \n\t"
"pushfl \n\t"
"popl %0"
: "=r" (eflags), "=a" (ax), "=d" (dx)
: "0" (eflags), "1" (ax), "g" (op2), "g" (arithmetic_eflags)
: "memory", "cc"
);
G_AX(vm) = ax;
G_DX(vm) = dx;
SetOSZAPC(vm, eflags);
}
void
IMUL_AXEw(vm_t *vm)
{
Bit16s op2, ax, dx;
Bit32u eflags, arithmetic_eflags;
ax = G_AX(vm);
if (vm->i.mod == 0xc0) {
op2 = ReadReg16(vm, vm->i.rm);
}
else {
read_virtual_word(vm, vm->i.seg, vm->i.rm_addr, &op2);
}
arithmetic_eflags = read_eflags(vm) & 0x000008d5;
eflags = 0; /* keep compiler quiet */
asm volatile (
/* First copy guest arithmetic flags to monitor flags */
"pushfl \n\t" /* Get mon flags */
"popl %0 \n\t"
"andl $0xfffff700, %0 \n\t" /* Erase mon arithmetic flags */
"orl %6, %0 \n\t" /* Or in guest arithmetic flags */
"pushl %0 \n\t" /* Set flags in mon */
"popfl \n\t"
"imulw %5 \n\t"
"pushfl \n\t"
"popl %0"
: "=r" (eflags), "=a" (ax), "=d" (dx)
: "0" (eflags), "1" (ax), "g" (op2), "g" (arithmetic_eflags)
: "memory", "cc"
);
G_AX(vm) = ax;
G_DX(vm) = dx;
SetOSZAPC(vm, eflags);
}
void
DIV_AXEw(vm_t *vm)
{
Bit16u op2, ax, dx;
Bit32u eflags, arithmetic_eflags;
dx = G_DX(vm);
ax = G_AX(vm);
if (vm->i.mod == 0xc0) {
op2 = ReadReg16(vm, vm->i.rm);
}
else {
read_virtual_word(vm, vm->i.seg, vm->i.rm_addr, &op2);
}
if (op2 == 0) {
exception(vm, ExceptionDE, 0);
}
arithmetic_eflags = read_eflags(vm) & 0x000008d5;
eflags = 0; /* keep compiler quiet */
asm volatile (
/* First copy guest arithmetic flags to monitor flags */
"pushfl \n\t" /* Get mon flags */
"popl %0 \n\t"
"andl $0xfffff700, %0 \n\t" /* Erase mon arithmetic flags */
"orl %7, %0 \n\t" /* Or in guest arithmetic flags */
"pushl %0 \n\t" /* Set flags in mon */
"popfl \n\t"
"divw %6 \n\t"
"pushfl \n\t"
"popl %0"
: "=r" (eflags), "=a" (ax), "=d" (dx)
: "0" (eflags), "1" (ax), "2" (dx), "g" (op2), "g" (arithmetic_eflags)
: "memory", "cc"
);
G_AX(vm) = ax;
G_DX(vm) = dx;
SetOSZAPC(vm, eflags);
}
void
IDIV_AXEw(vm_t *vm)
{
Bit16u op2, ax, dx;
Bit32u eflags, arithmetic_eflags;
dx = G_DX(vm);
ax = G_AX(vm);
if (vm->i.mod == 0xc0) {
op2 = ReadReg16(vm, vm->i.rm);
}
else {
read_virtual_word(vm, vm->i.seg, vm->i.rm_addr, &op2);
}
if (op2 == 0) {
exception(vm, ExceptionDE, 0);
}
arithmetic_eflags = read_eflags(vm) & 0x000008d5;
eflags = 0; /* keep compiler quiet */
asm volatile (
/* First copy guest arithmetic flags to monitor flags */
"pushfl \n\t" /* Get mon flags */
"popl %0 \n\t"
"andl $0xfffff700, %0 \n\t" /* Erase mon arithmetic flags */
"orl %7, %0 \n\t" /* Or in guest arithmetic flags */
"pushl %0 \n\t" /* Set flags in mon */
"popfl \n\t"
"idivw %6 \n\t"
"pushfl \n\t"
"popl %0"
: "=r" (eflags), "=a" (ax), "=d" (dx)
: "0" (eflags), "1" (ax), "2" (dx), "g" (op2), "g" (arithmetic_eflags)
: "memory", "cc"
);
G_AX(vm) = ax;
G_DX(vm) = dx;
SetOSZAPC(vm, eflags);
}
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