mirrors/Bochs
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
0dc4badfbb
Bochs/bochs/cpu/flag_ctrl.cc

348 lines
8.2 KiB
C++
Raw Blame History

/////////////////////////////////////////////////////////////////////////
// $Id: flag_ctrl.cc,v 1.26 2006-06-09 22:29:07 sshwarts Exp $
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2002 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"
#include "cpu.h"
#define LOG_THIS BX_CPU_THIS_PTR
void BX_CPU_C::SAHF(bxInstruction_c *i)
{
set_SF((AH & 0x80) >> 7);
set_ZF((AH & 0x40) >> 6);
set_AF((AH & 0x10) >> 4);
set_CF(AH & 0x01);
set_PF((AH & 0x04) >> 2);
}
void BX_CPU_C::LAHF(bxInstruction_c *i)
{
AH = (get_SF() ? 0x80 : 0) |
(get_ZF() ? 0x40 : 0) |
(get_AF() ? 0x10 : 0) |
(get_PF() ? 0x04 : 0) |
(0x02) |
(get_CF() ? 0x01 : 0);
}
void BX_CPU_C::CLC(bxInstruction_c *i)
{
clear_CF();
}
void BX_CPU_C::STC(bxInstruction_c *i)
{
assert_CF();
}
void BX_CPU_C::CLI(bxInstruction_c *i)
{
Bit32u IOPL = BX_CPU_THIS_PTR get_IOPL();
Bit32u cpl = CPL;
#if BX_CPU_LEVEL >= 2
if (protected_mode())
{
#if BX_SUPPORT_VME
if (BX_CPU_THIS_PTR cr4.get_PVI() && (cpl == 3))
{
if (IOPL < 3) {
BX_CPU_THIS_PTR clear_VIF();
return;
}
}
else
#endif
{
if (IOPL < cpl) {
BX_DEBUG(("CLI: IOPL < CPL in protected mode"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
}
#if BX_CPU_LEVEL >= 3
else if (v8086_mode())
{
if (IOPL != 3) {
#if BX_SUPPORT_VME
if (CR4_VME_ENABLED) {
BX_CPU_THIS_PTR clear_VIF();
return;
}
#endif
BX_DEBUG(("CLI: IOPL != 3 in v8086 mode"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
#endif
#endif
BX_CPU_THIS_PTR clear_IF();
}
void BX_CPU_C::STI(bxInstruction_c *i)
{
Bit32u IOPL = BX_CPU_THIS_PTR get_IOPL();
Bit32u cpl = CPL;
#if BX_CPU_LEVEL >= 2
if (protected_mode())
{
#if BX_SUPPORT_VME
if (BX_CPU_THIS_PTR cr4.get_PVI())
{
if (cpl == 3 && IOPL < 3) {
if (! BX_CPU_THIS_PTR get_VIP())
{
BX_CPU_THIS_PTR assert_VIF();
return;
}
BX_DEBUG(("STI: #GP(0) in VME mode"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
#endif
if (cpl > IOPL) {
BX_DEBUG(("STI: CPL > IOPL in protected mode"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
#if BX_CPU_LEVEL >= 3
else if (v8086_mode())
{
if (IOPL != 3) {
#if BX_SUPPORT_VME
if (CR4_VME_ENABLED && BX_CPU_THIS_PTR get_VIP() == 0)
{
BX_CPU_THIS_PTR assert_VIF();
return;
}
#endif
BX_DEBUG(("STI: IOPL != 3 in v8086 mode"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
#endif
#endif
if (!BX_CPU_THIS_PTR get_IF()) {
BX_CPU_THIS_PTR assert_IF();
BX_CPU_THIS_PTR inhibit_mask |= BX_INHIBIT_INTERRUPTS;
BX_CPU_THIS_PTR async_event = 1;
}
}
void BX_CPU_C::CLD(bxInstruction_c *i)
{
BX_CPU_THIS_PTR clear_DF();
}
void BX_CPU_C::STD(bxInstruction_c *i)
{
BX_CPU_THIS_PTR assert_DF();
}
void BX_CPU_C::CMC(bxInstruction_c *i)
{
set_CF(! get_CF());
}
void BX_CPU_C::PUSHF_Fw(bxInstruction_c *i)
{
Bit16u flags = read_flags();
if (v8086_mode()) {
if ((BX_CPU_THIS_PTR get_IOPL() < 3) && (CR4_VME_ENABLED == 0)) {
BX_DEBUG(("PUSHFW: #GP(0) in v8086 (no VME) mode"));
exception(BX_GP_EXCEPTION, 0, 0);
return;
}
#if BX_SUPPORT_VME
if (CR4_VME_ENABLED && BX_CPU_THIS_PTR get_IOPL() < 3) {
flags |= EFlagsIOPLMask;
if (BX_CPU_THIS_PTR get_VIF())
flags |= EFlagsIFMask;
else
flags &= ~EFlagsIFMask;
}
#endif
}
push_16(flags);
}
void BX_CPU_C::POPF_Fw(bxInstruction_c *i)
{
// Build a mask of the following bits:
// x,NT,IOPL,OF,DF,IF,TF,SF,ZF,x,AF,x,PF,x,CF
Bit32u changeMask = EFlagsOSZAPCMask | EFlagsTFMask | EFlagsDFMask;
#if BX_CPU_LEVEL >= 3
changeMask |= EFlagsNTMask; // NT could be modified
#endif
Bit16u flags16;
if (protected_mode()) {
pop_16(&flags16);
if (CPL==0)
changeMask |= EFlagsIOPLMask;
if (CPL <= BX_CPU_THIS_PTR get_IOPL())
changeMask |= EFlagsIFMask;
}
else if (v8086_mode()) {
if ((BX_CPU_THIS_PTR get_IOPL() < 3) && (CR4_VME_ENABLED == 0)) {
BX_DEBUG(("POPFW: #GP(0) in v8086 (no VME) mode"));
exception(BX_GP_EXCEPTION, 0, 0);
return;
}
pop_16(&flags16);
#if BX_SUPPORT_VME
if (CR4_VME_ENABLED && BX_CPU_THIS_PTR get_IOPL() < 3) {
if (((flags16 & EFlagsIFMask) && BX_CPU_THIS_PTR get_VIP()) ||
(flags16 & EFlagsTFMask))
{
BX_DEBUG(("POPFW: #GP(0) in VME mode"));
exception(BX_GP_EXCEPTION, 0, 0);
}
// IF, IOPL unchanged, EFLAGS.VIF = TMP_FLAGS.IF
changeMask |= EFlagsVIFMask;
Bit32u flags32 = (Bit32u) flags16;
if (BX_CPU_THIS_PTR get_IF()) flags32 |= EFlagsVIFMask;
writeEFlags(flags32, changeMask);
return;
}
#endif
changeMask |= EFlagsIFMask;
}
else {
pop_16(&flags16);
// All non-reserved flags can be modified
changeMask |= (EFlagsIOPLMask | EFlagsIFMask);
}
writeEFlags((Bit32u) flags16, changeMask);
}
#if BX_CPU_LEVEL >= 3
void BX_CPU_C::PUSHF_Fd(bxInstruction_c *i)
{
if (v8086_mode() && (BX_CPU_THIS_PTR get_IOPL()<3)) {
BX_DEBUG(("PUSHFD: #GP(0) in v8086 mode"));
exception(BX_GP_EXCEPTION, 0, 0);
return;
}
// VM & RF flags cleared in image stored on the stack
push_32(read_eflags() & 0x00fcffff);
}
void BX_CPU_C::POPF_Fd(bxInstruction_c *i)
{
// Build a mask of the following bits:
// ID,VIP,VIF,AC,VM,RF,x,NT,IOPL,OF,DF,IF,TF,SF,ZF,x,AF,x,PF,x,CF
Bit32u changeMask = EFlagsOSZAPCMask | EFlagsTFMask |
EFlagsDFMask | EFlagsNTMask | EFlagsRFMask;
#if BX_CPU_LEVEL >= 4
changeMask |= (EFlagsIDMask | EFlagsACMask); // ID/AC
#endif
Bit32u flags32;
if (protected_mode()) {
pop_32(&flags32);
// IOPL changed only if (CPL == 0),
// IF changed only if (CPL <= EFLAGS.IOPL),
// VIF, VIP, VM are unaffected
if (CPL==0)
changeMask |= EFlagsIOPLMask;
if (CPL <= BX_CPU_THIS_PTR get_IOPL())
changeMask |= EFlagsIFMask;
}
else if (v8086_mode()) {
if (BX_CPU_THIS_PTR get_IOPL() < 3) {
BX_DEBUG(("POPFD: #GP(0) in v8086 mode"));
exception(BX_GP_EXCEPTION, 0, 0);
return;
}
pop_32(&flags32);
// v8086-mode: VM, IOPL, VIP, VIF are unaffected
changeMask |= EFlagsIFMask;
}
else { // Real-mode
pop_32(&flags32);
// VIF, VIP, VM are unaffected
changeMask |= (EFlagsIOPLMask | EFlagsIFMask);
}
writeEFlags(flags32, changeMask);
}
#if BX_SUPPORT_X86_64
void BX_CPU_C::PUSHF_Fq(bxInstruction_c *i)
{
// VM & RF flags cleared in image stored on the stack
push_64(read_eflags() & 0x00fcffff);
}
void BX_CPU_C::POPF_Fq(bxInstruction_c *i)
{
// Build a mask of the following bits:
// ID,VIP,VIF,AC,VM,RF,x,NT,IOPL,OF,DF,IF,TF,SF,ZF,x,AF,x,PF,x,CF
Bit32u changeMask = EFlagsOSZAPCMask | EFlagsTFMask | EFlagsDFMask
| EFlagsNTMask | EFlagsRFMask | EFlagsACMask
| EFlagsIDMask;
Bit64u flags64;
BX_ASSERT (protected_mode());
pop_64(&flags64);
Bit32u flags32 = (Bit32u) flags64;
if (CPL==0)
changeMask |= EFlagsIOPLMask;
if (CPL <= BX_CPU_THIS_PTR get_IOPL())
changeMask |= EFlagsIFMask;
// VIF, VIP, VM are unaffected
writeEFlags(flags32, changeMask);
}
#endif
#endif // BX_CPU_LEVEL >= 3
void BX_CPU_C::SALC(bxInstruction_c *i)
{
if (get_CF()) {
AL = 0xff;
}
else {
AL = 0x00;
}
}
Reference in New Issue View Git Blame Copy Permalink