fpu_regs.h

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/****************************************************************************
*
*               Realmode X86 Emulator Library
*
*                       Copyright (C) 1996-1999 SciTech Software, Inc.
*                                    Copyright (C) David Mosberger-Tang
*                                          Copyright (C) 1999 Egbert Eich
*
*  ========================================================================
*
*  Permission to use, copy, modify, distribute, and sell this software and
*  its documentation for any purpose is hereby granted without fee,
*  provided that the above copyright notice appear in all copies and that
*  both that copyright notice and this permission notice appear in
*  supporting documentation, and that the name of the authors not be used
*  in advertising or publicity pertaining to distribution of the software
*  without specific, written prior permission.  The authors makes no
*  representations about the suitability of this software for any purpose.
*  It is provided "as is" without express or implied warranty.
*
*  THE AUTHORS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
*  INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
*  EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
*  CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
*  USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
*  OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
*  PERFORMANCE OF THIS SOFTWARE.
*
*  ========================================================================
*
* Language:             ANSI C
* Environment:  Any
* Developer:    Kendall Bennett
*
* Description:  Header file for FPU register definitions.
*
****************************************************************************/
 
#ifndef __X86EMU_FPU_REGS_H
#define __X86EMU_FPU_REGS_H
 
#ifdef X86_FPU_SUPPORT
 
#pragma pack(1)
 
/* Basic 8087 register can hold any of the following values: */
 
union x86_fpu_reg_u {
        s8                  tenbytes[10];
        double              dval;
        float               fval;
        s16                 sval;
        s32                 lval;
        };
 
struct x86_fpu_reg {
        union x86_fpu_reg_u reg;
        char                tag;
        };
 
/*
 * Since we are not going to worry about the problems of aliasing
 * registers, every time a register is modified, its result type is
 * set in the tag fields for that register.  If some operation
 * attempts to access the type in a way inconsistent with its current
 * storage format, then we flag the operation.  If common, we'll
 * attempt the conversion.
 */
 
#define  X86_FPU_VALID          0x80
#define  X86_FPU_REGTYP(r)      ((r) & 0x7F)
 
#define  X86_FPU_WORD           0x0
#define  X86_FPU_SHORT          0x1
#define  X86_FPU_LONG           0x2
#define  X86_FPU_FLOAT          0x3
#define  X86_FPU_DOUBLE         0x4
#define  X86_FPU_LDBL           0x5
#define  X86_FPU_BSD            0x6
 
#define  X86_FPU_STKTOP  0
 
struct x86_fpu_registers {
        struct x86_fpu_reg  x86_fpu_stack[8];
        int                 x86_fpu_flags;
        int                 x86_fpu_config;         /* rounding modes, etc. */
        short               x86_fpu_tos, x86_fpu_bos;
        };
 
#pragma pack()
 
/*
 * There are two versions of the following macro.
 *
 * One version is for opcode D9, for which there are more than 32
 * instructions encoded in the second byte of the opcode.
 *
 * The other version, deals with all the other 7 i87 opcodes, for
 * which there are only 32 strings needed to describe the
 * instructions.
 */
 
#endif /* X86_FPU_SUPPORT */
 
#if CONFIG(X86EMU_DEBUG)
# define DECODE_PRINTINSTR32(t, mod, rh, rl)    \
        DECODE_PRINTF(t[(mod<<3)+(rh)])
# define DECODE_PRINTINSTR256(t, mod, rh, rl)   \
        DECODE_PRINTF(t[(mod<<6)+(rh<<3)+(rl)])
#else
# define DECODE_PRINTINSTR32(t, mod, rh, rl)
# define DECODE_PRINTINSTR256(t, mod, rh, rl)
#endif
 
#endif /* __X86EMU_FPU_REGS_H */