Bochs/bochs/cpu/flag_ctrl_pro.cc
Bryce Denney 450070850b - the debugger was broken by recent changes in the cpu flags. To provide
a consistent way of accessing these flags that works both inside and
  outside the BX_CPU class, I added inline accessor methods for each
  flag: assert_FLAG(), clear_FLAG(), set_FLAG(value), and get_FLAG ()
  that returns its value.  I use assert to mean "set the value to one"
  to avoid confusion, since there's also a set method that takes a value.
- the eflags access macros (e.g. GetEFlagsDFLogical, ClearEFlagsTF) are
  now defined in terms of the inline accessors.  In most cases it will
  result in the same code anyway.  The major advantage of the accesors
  is that they can be used from inside or outside the BX_CPU object, while
  the macros can only be used from inside.
- since almost all eflags were stored in val32 now, I went ahead and
  removed the if_, rf, and vm fields.  Now the val32 bit is the
  "official" value for these flags, and they have accessors just like
  everything else.
- init.cc: move the registration of registers until after they have been
  initialized so that the initial value of each parameter is correct.

Modified files:
  debug/dbg_main.cc cpu/cpu.h cpu/debugstuff.cc cpu/flag_ctrl.cc
  cpu/flag_ctrl_pro.cc cpu/init.cc
2002-09-11 03:55:22 +00:00

189 lines
4.7 KiB
C++

/////////////////////////////////////////////////////////////////////////
// $Id: flag_ctrl_pro.cc,v 1.8 2002-09-11 03:55:22 bdenney 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::write_flags(Bit16u flags, Boolean change_IOPL, Boolean change_IF)
{
Bit32u changeMask; // Really should be passed in.
changeMask = 0x0dd5;
#if BX_CPU_LEVEL <= 2
// NT = 0
#else
changeMask |= (1<<14); // NT is modified as requested.
#endif
#if BX_CPU_LEVEL >= 3
if (change_IOPL)
changeMask |= (3<<12); // IOPL is modified as requested.
#else
// IOPL = 0
#endif
if (change_IF) {
changeMask |= (1<<9);
BX_CPU_THIS_PTR eflags.set_IF ((flags >> 9) & 0x01);
}
BX_CPU_THIS_PTR eflags.val32 =
(BX_CPU_THIS_PTR eflags.val32 & ~changeMask) | (flags & changeMask);
BX_CPU_THIS_PTR lf_flags_status = 0; // OSZAPC flags are known.
#if 0
// +++
if (GetEFlagsTFLogical()==0 && (flags&0x0100))
BX_DEBUG(( "TF 0->1" ));
else if (GetEFlagsTFLogical() && !(flags&0x0100))
BX_DEBUG(( "TF 1->0" ));
else if (GetEFlagsTFLogical() && (flags&0x0100))
BX_DEBUG(( "TF 1->1" ));
#endif
if ( flags & (1 << 8) ) {
BX_CPU_THIS_PTR async_event = 1; // TF = 1
}
}
#if BX_CPU_LEVEL >= 3
void
BX_CPU_C::write_eflags(Bit32u eflags_raw, Boolean change_IOPL, Boolean change_IF,
Boolean change_VM, Boolean change_RF)
{
Bit32u changeMask; // Really should be passed in.
changeMask = 0x4dd5;
#if BX_CPU_LEVEL >= 4
changeMask |= ((1<<21) | (1<<18)); // ID/AC
#endif
if (change_IOPL)
changeMask |= (3<<12);
if (change_IF)
changeMask |= (1<<9);
if (change_VM) {
changeMask |= (1<<17);
#if BX_SUPPORT_V8086_MODE == 0
if ( eflags_raw & (1<<17) )
BX_PANIC(("write_eflags: VM bit set: BX_SUPPORT_V8086_MODE==0"));
#endif
}
if (change_RF)
changeMask |= (1<<16);
BX_CPU_THIS_PTR eflags.val32 =
(BX_CPU_THIS_PTR eflags.val32 & ~changeMask) | (eflags_raw & changeMask);
BX_CPU_THIS_PTR lf_flags_status = 0; // OSZAPC flags are known.
#if 0
// +++
if (GetEFlagsTFLogical()==0 && (eflags_raw&0x0100))
BX_DEBUG(( "TF 0->1" ));
else if (GetEFlagsTFLogical() && !(eflags_raw&0x0100))
BX_DEBUG(( "TF 1->0" ));
else if (GetEFlagsTFLogical() && (eflags_raw&0x0100))
BX_DEBUG(( "TF 1->1" ));
#endif
if (eflags_raw & (1 << 8)) {
BX_CPU_THIS_PTR async_event = 1; // TF = 1
}
}
#endif /* BX_CPU_LEVEL >= 3 */
Bit16u
BX_CPU_C::read_flags(void)
{
Bit16u flags16;
// Cause arithmetic flags to be in known state and cached in val32.
if (BX_CPU_THIS_PTR lf_flags_status) {
(void) get_CF();
(void) get_PF();
(void) get_AF();
(void) get_ZF();
(void) get_SF();
(void) get_OF();
}
flags16 = (Bit16u) BX_CPU_THIS_PTR eflags.val32;
/* 8086: bits 12-15 always set to 1.
* 286: in real mode, bits 12-15 always cleared.
* 386+: real-mode: bit15 cleared, bits 14..12 are last loaded value
* protected-mode: bit 15 clear, bit 14 = last loaded, IOPL?
*/
#if BX_CPU_LEVEL < 2
flags16 |= 0xF000; /* 8086 nature */
#elif BX_CPU_LEVEL == 2
if (real_mode()) {
flags16 &= 0x0FFF; /* 80286 in real mode nature */
}
#else /* 386+ */
#endif
return(flags16);
}
#if BX_CPU_LEVEL >= 3
Bit32u
BX_CPU_C::read_eflags(void)
{
Bit32u flags32;
// Cause arithmetic flags to be in known state and cached in val32.
if (BX_CPU_THIS_PTR lf_flags_status) {
(void) get_CF();
(void) get_PF();
(void) get_AF();
(void) get_ZF();
(void) get_SF();
(void) get_OF();
}
flags32 = BX_CPU_THIS_PTR eflags.val32;
#if 0
/*
* 386+: real-mode: bit15 cleared, bits 14..12 are last loaded value
* protected-mode: bit 15 clear, bit 14 = last loaded, IOPL?
*/
#endif
return(flags32);
}
#endif /* BX_CPU_LEVEL >= 3 */