reactos/lib/fast486/fpu.h

   1 /*
   2  * Fast486 386/486 CPU Emulation Library
   3  * fpu.h
   4  *
   5  * Copyright (C) 2014 Aleksandar Andrejevic <theflash AT sdf DOT lonestar DOT org>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2
  10  * of the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  20  */
  21
  22 #ifndef _FPU_H_
  23 #define _FPU_H_
  24
  25 #pragma once
  26
  27 #include "opcodes.h"
  28
  29 /* DEFINES ********************************************************************/
  30
  31 #define FPU_CHECK() if (State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_EM) \
  32                     { \
  33                         Fast486Exception(State, FAST486_EXCEPTION_NM); \
  34                         return FALSE; \
  35                     }
  36 #define FPU_ST(i) State->FpuRegisters[(State->FpuStatus.Top + (i)) % FAST486_NUM_FPU_REGS]
  37 #define FPU_GET_TAG(i)  ((State->FpuTag >> ((i) * 2)) & 3)
  38 #define FPU_SET_TAG(i, t)   { \
  39                                 State->FpuTag &= ~((1 << ((i) * 2)) | (1 << (((i) * 2) + 1))); \
  40                                 State->FpuTag |= ((t) & 3) << ((i) * 2); \
  41                             }
  42
  43 #define FPU_REAL4_BIAS 0x7F
  44 #define FPU_REAL8_BIAS 0x3FF
  45 #define FPU_REAL10_BIAS 0x3FFF
  46 #define FPU_MAX_EXPONENT 0x7FFE
  47 #define FPU_MANTISSA_HIGH_BIT 0x8000000000000000ULL
  48
  49 #define FPU_IS_NORMALIZED(x) (!FPU_IS_ZERO(x) && (((x)->Mantissa & FPU_MANTISSA_HIGH_BIT) != 0ULL))
  50 #define FPU_IS_ZERO(x) ((x)->Mantissa == 0ULL)
  51 #define FPU_IS_NAN(x) ((x)->Exponent == (FPU_MAX_EXPONENT + 1))
  52 #define FPU_IS_INFINITY(x) (FPU_IS_NAN(x) && (x)->Mantissa & FPU_MANTISSA_HIGH_BIT)
  53 #define FPU_IS_POS_INF(x) (FPU_IS_INFINITY(x) && !(x)->Sign)
  54 #define FPU_IS_NEG_INF(x) (FPU_IS_INFINITY(x) && (x)->Sign)
  55
  56 enum
  57 {
  58     FPU_SINGLE_PRECISION = 0,
  59     FPU_DOUBLE_PRECISION = 2,
  60     FPU_DOUBLE_EXT_PRECISION = 3
  61 };
  62
  63 enum
  64 {
  65     FPU_TAG_VALID = 0,
  66     FPU_TAG_ZERO = 1,
  67     FPU_TAG_SPECIAL = 2,
  68     FPU_TAG_EMPTY = 3
  69 };
  70
  71 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeD8DC);
  72 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeD9);
  73 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDA);
  74 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDB);
  75 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDD);
  76 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDE);
  77 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDF);
  78
  79 #endif // _FPU_H_
  80
  81 /* EOF */