1 /* 2 * Fast486 386/486 CPU Emulation Library 3 * fpu.h 4 * 5 * Copyright (C) 2015 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 | FAST486_CR0_TS)) \ 32 { \ 33 Fast486Exception(State, FAST486_EXCEPTION_NM); \ 34 return; \ 35 } 36 #define FPU_INDEX(i) ((State->FpuStatus.Top + (i)) % FAST486_NUM_FPU_REGS) 37 #define FPU_ST(i) State->FpuRegisters[FPU_INDEX(i)] 38 39 #define FPU_GET_TAG(i) ((State->FpuTag >> (FPU_INDEX(i) * 2)) & 3) 40 #define FPU_SET_TAG(i, t) { \ 41 State->FpuTag &= ~((1 << (FPU_INDEX(i) * 2)) | (1 << ((FPU_INDEX(i) * 2) + 1))); \ 42 State->FpuTag |= ((t) & 3) << (FPU_INDEX(i) * 2); \ 43 } 44 #define FPU_UPDATE_TAG(i) FPU_SET_TAG((i), Fast486FpuGetValueTag(&FPU_ST(i))) 45 #define FPU_SAVE_LAST_INST() { \ 46 State->FpuLastInstPtr = State->SavedInstPtr; \ 47 State->FpuLastCodeSel = State->SegmentRegs[FAST486_REG_CS].Selector; \ 48 } 49 #define FPU_SAVE_LAST_OPERAND() { \ 50 State->FpuLastOpPtr.Long = ModRegRm.MemoryAddress; \ 51 State->FpuLastDataSel = (State->PrefixFlags & FAST486_PREFIX_SEG) \ 52 ? State->SegmentOverride : FAST486_REG_DS; \ 53 } 54 55 #define FPU_REAL4_BIAS 0x7F 56 #define FPU_REAL8_BIAS 0x3FF 57 #define FPU_REAL10_BIAS 0x3FFF 58 #define FPU_MAX_EXPONENT 0x7FFE 59 #define FPU_MANTISSA_HIGH_BIT 0x8000000000000000ULL 60 #define FPU_INDEFINITE_MANTISSA 0xC000000000000000ULL 61 #define FPU_REAL4_INFINITY 0x7F800000 62 #define FPU_REAL4_INDEFINITE 0xFFC00000 63 #define FPU_REAL8_INFINITY 0x7FF0000000000000ULL 64 #define FPU_REAL8_INDEFINITE 0xFFF8000000000000ULL 65 66 #define FPU_IS_NORMALIZED(x) (FPU_IS_ZERO(x) || (((x)->Mantissa & FPU_MANTISSA_HIGH_BIT) != 0ULL)) 67 #define FPU_IS_ZERO(x) ((x)->Mantissa == 0ULL) 68 #define FPU_IS_NAN(x) ((x)->Exponent == (FPU_MAX_EXPONENT + 1)) 69 #define FPU_IS_INFINITY(x) (FPU_IS_NAN(x) && ((x)->Mantissa == FPU_MANTISSA_HIGH_BIT)) 70 #define FPU_IS_POS_INF(x) (FPU_IS_INFINITY(x) && !(x)->Sign) 71 #define FPU_IS_NEG_INF(x) (FPU_IS_INFINITY(x) && (x)->Sign) 72 #define FPU_IS_INDEFINITE(x) (FPU_IS_NAN(x) && !FPU_IS_INFINITY(x)) 73 74 #define INVERSE_NUMBERS_COUNT 50 75 76 enum 77 { 78 FPU_SINGLE_PRECISION = 0, 79 FPU_DOUBLE_PRECISION = 2, 80 FPU_DOUBLE_EXT_PRECISION = 3 81 }; 82 83 enum 84 { 85 FPU_TAG_VALID = 0, 86 FPU_TAG_ZERO = 1, 87 FPU_TAG_SPECIAL = 2, 88 FPU_TAG_EMPTY = 3 89 }; 90 91 enum 92 { 93 FPU_ROUND_NEAREST = 0, 94 FPU_ROUND_DOWN = 1, 95 FPU_ROUND_UP = 2, 96 FPU_ROUND_TRUNCATE = 3 97 }; 98 99 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeD8); 100 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeD9); 101 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDA); 102 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDB); 103 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDC); 104 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDD); 105 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDE); 106 FAST486_OPCODE_HANDLER(Fast486FpuOpcodeDF); 107 108 #endif // _FPU_H_ 109 110 /* EOF */ 111