contrib/FAQ/programs/fp-emu/fpemul/math_emu.h

#ifndef _MATH_EMU_H
#define _MATH_EMU_H

struct fpu_reg {
        char    sign;
        char    tag;
        long    exp;
        u_long  sigl;
        u_long  sigh;
};

union i387_union {
        struct i387_hard_struct {
                long    cwd;
                long    swd;
                long    twd;
                long    fip;
                long    fcs;
                long    foo;
                long    fos;
                long    st_space[20];   /* 8*10 bytes for each FP-reg = 80
                                         * bytes */
        }       hard;
        struct i387_soft_struct {
                long    cwd;
                long    swd;
                long    twd;
                long    fip;
                long    fcs;
                long    foo;
                long    fos;
                long    top;
                struct fpu_reg regs[8]; /* 8*16 bytes for each FP-reg = 128
                                         * bytes */
                unsigned char lookahead;
                struct trapframe *frame;
                unsigned long entry_eip;
                int     orig_eip;
        }       soft;
};
#endif