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Bochs/bochs/cpu/lazy_flags.cc
Stanislav Shwartsman 2aaafa76a2 Reorganize fetchdecode tables with another level of redirection - a leap toward future improvements 
Currently no speedup and no slowdown - about the same results on my Bochs benchmarking
A lot of code reorganization in fetchdecode
2008-04-04 22:39:45 +00:00

353 lines
11 KiB
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/////////////////////////////////////////////////////////////////////////
// $Id: lazy_flags.cc,v 1.46 2008-04-04 22:39:45 sshwarts 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"
#include "cpu.h"
#define LOG_THIS BX_CPU_THIS_PTR
// This array defines a look-up table for the even parity-ness
// of an 8bit quantity, for optimal assignment of the parity bit
// in the EFLAGS register
const bx_bool bx_parity_lookup[256] = {
1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1
};
#define result_8 ((Bit8u) (BX_CPU_THIS_PTR oszapc.result))
#define result_16 ((Bit16u)(BX_CPU_THIS_PTR oszapc.result))
#define result_32 ((Bit32u)(BX_CPU_THIS_PTR oszapc.result))
#define result_64 (BX_CPU_THIS_PTR oszapc.result)
bx_bool BX_CPU_C::get_CFLazy(void)
{
unsigned cf;
switch (BX_CPU_THIS_PTR oszapc.instr) {
case BX_LF_INSTR_ADD8:
cf = (result_8 < BX_CPU_THIS_PTR oszapc.op1_8);
break;
case BX_LF_INSTR_ADD16:
cf = (result_16 < BX_CPU_THIS_PTR oszapc.op1_16);
break;
case BX_LF_INSTR_ADD32:
cf = (result_32 < BX_CPU_THIS_PTR oszapc.op1_32);
break;
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_ADD64:
cf = (result_64 < BX_CPU_THIS_PTR oszapc.op1_64);
break;
#endif
// used only if CF = 1 when executing ADC instruction
case BX_LF_INSTR_ADC8:
cf = (result_8 <= BX_CPU_THIS_PTR oszapc.op1_8);
break;
// used only if CF = 1 when executing ADC instruction
case BX_LF_INSTR_ADC16:
cf = (result_16 <= BX_CPU_THIS_PTR oszapc.op1_16);
break;
// used only if CF = 1 when executing ADC instruction
case BX_LF_INSTR_ADC32:
cf = (result_32 <= BX_CPU_THIS_PTR oszapc.op1_32);
break;
#if BX_SUPPORT_X86_64
// used only if CF = 1 when executing ADC instruction
case BX_LF_INSTR_ADC64:
cf = (result_64 <= BX_CPU_THIS_PTR oszapc.op1_64);
break;
#endif
case BX_LF_INSTR_SUB8:
cf = (BX_CPU_THIS_PTR oszapc.op1_8 <
BX_CPU_THIS_PTR oszapc.op2_8);
break;
case BX_LF_INSTR_SUB16:
cf = (BX_CPU_THIS_PTR oszapc.op1_16 <
BX_CPU_THIS_PTR oszapc.op2_16);
break;
case BX_LF_INSTR_SUB32:
cf = (BX_CPU_THIS_PTR oszapc.op1_32 <
BX_CPU_THIS_PTR oszapc.op2_32);
break;
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_SUB64:
cf = (BX_CPU_THIS_PTR oszapc.op1_64 <
BX_CPU_THIS_PTR oszapc.op2_64);
break;
#endif
// used only if CF = 1 when executing SBB instruction
case BX_LF_INSTR_SBB8:
cf = (BX_CPU_THIS_PTR oszapc.op1_8 < result_8) ||
(BX_CPU_THIS_PTR oszapc.op2_8==0xff);
break;
// used only if CF = 1 when executing SBB instruction
case BX_LF_INSTR_SBB16:
cf = (BX_CPU_THIS_PTR oszapc.op1_16 < result_16) ||
(BX_CPU_THIS_PTR oszapc.op2_16==0xffff);
break;
// used only if CF = 1 when executing SBB instruction
case BX_LF_INSTR_SBB32:
cf = (BX_CPU_THIS_PTR oszapc.op1_32 < result_32) ||
(BX_CPU_THIS_PTR oszapc.op2_32==0xffffffff);
break;
#if BX_SUPPORT_X86_64
// used only if CF = 1 when executing SBB instruction
case BX_LF_INSTR_SBB64:
cf = (BX_CPU_THIS_PTR oszapc.op1_64 < result_64) ||
(BX_CPU_THIS_PTR oszapc.op2_64==BX_CONST64(0xffffffffffffffff));
break;
#endif
case BX_LF_INSTR_NEG8:
cf = (result_8 != 0);
break;
case BX_LF_INSTR_NEG16:
cf = (result_16 != 0);
break;
case BX_LF_INSTR_NEG32:
cf = (result_32 != 0);
break;
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_NEG64:
cf = (result_64 != 0);
break;
#endif
case BX_LF_INSTR_LOGIC8:
case BX_LF_INSTR_LOGIC16:
case BX_LF_INSTR_LOGIC32:
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_LOGIC64:
#endif
cf = 0;
break;
default:
cf = 0; // Keep compiler quiet.
BX_PANIC(("get_CF: OSZAPC: unknown instr %u",
(unsigned) BX_CPU_THIS_PTR oszapc.instr));
}
return(cf);
}
bx_bool BX_CPU_C::get_AFLazy(void)
{
unsigned af;
switch (BX_CPU_THIS_PTR oszapc.instr) {
case BX_LF_INSTR_ADD8:
case BX_LF_INSTR_ADC8:
case BX_LF_INSTR_SUB8:
case BX_LF_INSTR_SBB8:
af = ((BX_CPU_THIS_PTR oszapc.op1_8 ^
BX_CPU_THIS_PTR oszapc.op2_8) ^ result_8) & 0x10;
break;
case BX_LF_INSTR_ADD16:
case BX_LF_INSTR_ADC16:
case BX_LF_INSTR_SUB16:
case BX_LF_INSTR_SBB16:
af = ((BX_CPU_THIS_PTR oszapc.op1_16 ^
BX_CPU_THIS_PTR oszapc.op2_16) ^ result_16) & 0x10;
break;
case BX_LF_INSTR_ADD32:
case BX_LF_INSTR_ADC32:
case BX_LF_INSTR_SUB32:
case BX_LF_INSTR_SBB32:
af = ((BX_CPU_THIS_PTR oszapc.op1_32 ^
BX_CPU_THIS_PTR oszapc.op2_32) ^ result_32) & 0x10;
break;
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_ADD64:
case BX_LF_INSTR_ADC64:
case BX_LF_INSTR_SUB64:
case BX_LF_INSTR_SBB64:
af = ((BX_CPU_THIS_PTR oszapc.op1_64 ^
BX_CPU_THIS_PTR oszapc.op2_64) ^ result_64) & 0x10;
break;
#endif
case BX_LF_INSTR_NEG8:
case BX_LF_INSTR_NEG16:
case BX_LF_INSTR_NEG32:
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_NEG64:
#endif
af = (result_8 & 0xf) != 0;
break;
case BX_LF_INSTR_INC8:
case BX_LF_INSTR_INC16:
case BX_LF_INSTR_INC32:
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_INC64:
#endif
af = (result_8 & 0xf) == 0;
break;
case BX_LF_INSTR_DEC8:
case BX_LF_INSTR_DEC16:
case BX_LF_INSTR_DEC32:
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_DEC64:
#endif
af = (result_8 & 0xf) == 0xf;
break;
case BX_LF_INSTR_LOGIC8:
case BX_LF_INSTR_LOGIC16:
case BX_LF_INSTR_LOGIC32:
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_LOGIC64:
#endif
af = 0;
break;
default:
af = 0; // Keep compiler quiet.
BX_PANIC(("get_AF: OSZAPC: unknown instr %u", (unsigned) BX_CPU_THIS_PTR oszapc.instr));
}
return(af);
}
#define GET_ADD_OVERFLOW(op1, op2, result, mask) \
(((~((op1) ^ (op2)) & ((op2) ^ (result))) & (mask)) != 0)
#define GET_SUB_OVERFLOW(op1, op2, result, mask) \
(((((op1) ^ (op2)) & ((op1) ^ (result))) & (mask)) != 0)
bx_bool BX_CPU_C::get_OFLazy(void)
{
unsigned of;
switch (BX_CPU_THIS_PTR oszapc.instr) {
case BX_LF_INSTR_ADD8:
case BX_LF_INSTR_ADC8:
of = GET_ADD_OVERFLOW(BX_CPU_THIS_PTR oszapc.op1_8,
BX_CPU_THIS_PTR oszapc.op2_8,
result_8, 0x80);
break;
case BX_LF_INSTR_ADD16:
case BX_LF_INSTR_ADC16:
of = GET_ADD_OVERFLOW(BX_CPU_THIS_PTR oszapc.op1_16,
BX_CPU_THIS_PTR oszapc.op2_16,
result_16, 0x8000);
break;
case BX_LF_INSTR_ADD32:
case BX_LF_INSTR_ADC32:
of = GET_ADD_OVERFLOW(BX_CPU_THIS_PTR oszapc.op1_32,
BX_CPU_THIS_PTR oszapc.op2_32,
result_32, 0x80000000);
break;
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_ADD64:
case BX_LF_INSTR_ADC64:
of = GET_ADD_OVERFLOW(BX_CPU_THIS_PTR oszapc.op1_64,
BX_CPU_THIS_PTR oszapc.op2_64,
result_64, BX_CONST64(0x8000000000000000));
break;
#endif
case BX_LF_INSTR_SUB8:
case BX_LF_INSTR_SBB8:
of = GET_SUB_OVERFLOW(BX_CPU_THIS_PTR oszapc.op1_8,
BX_CPU_THIS_PTR oszapc.op2_8,
result_8, 0x80);
break;
case BX_LF_INSTR_SUB16:
case BX_LF_INSTR_SBB16:
of = GET_SUB_OVERFLOW(BX_CPU_THIS_PTR oszapc.op1_16,
BX_CPU_THIS_PTR oszapc.op2_16,
result_16, 0x8000);
break;
case BX_LF_INSTR_SUB32:
case BX_LF_INSTR_SBB32:
of = GET_SUB_OVERFLOW(BX_CPU_THIS_PTR oszapc.op1_32,
BX_CPU_THIS_PTR oszapc.op2_32,
result_32, 0x80000000);
break;
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_SUB64:
case BX_LF_INSTR_SBB64:
of = GET_SUB_OVERFLOW(BX_CPU_THIS_PTR oszapc.op1_64,
BX_CPU_THIS_PTR oszapc.op2_64,
result_64, BX_CONST64(0x8000000000000000));
break;
#endif
case BX_LF_INSTR_LOGIC8:
case BX_LF_INSTR_LOGIC16:
case BX_LF_INSTR_LOGIC32:
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_LOGIC64:
#endif
of = 0;
break;
case BX_LF_INSTR_NEG8:
case BX_LF_INSTR_INC8:
of = (result_8 == 0x80);
break;
case BX_LF_INSTR_NEG16:
case BX_LF_INSTR_INC16:
of = (result_16 == 0x8000);
break;
case BX_LF_INSTR_NEG32:
case BX_LF_INSTR_INC32:
of = (result_32 == 0x80000000);
break;
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_NEG64:
case BX_LF_INSTR_INC64:
of = (result_64 == BX_CONST64(0x8000000000000000));
break;
#endif
case BX_LF_INSTR_DEC8:
of = (result_8 == 0x7F);
break;
case BX_LF_INSTR_DEC16:
of = (result_16 == 0x7FFF);
break;
case BX_LF_INSTR_DEC32:
of = (result_32 == 0x7FFFFFFF);
break;
#if BX_SUPPORT_X86_64
case BX_LF_INSTR_DEC64:
of = (result_64 == BX_CONST64(0x7FFFFFFFFFFFFFFF));
break;
#endif
default:
of = 0; // Keep compiler happy.
BX_PANIC(("get_OF: OSZAPC: unknown instr"));
}
return(of);
}
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