/* syscall defines for MMIXware.

   Copyright (C) 2001 Hans-Peter Nilsson.

   Permission to use, copy, modify, and distribute this software is freely
   granted, provided that this notice is preserved with no changes.
   THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
   IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   PURPOSE.  */

/* These are the mmixware simulator calls that are of use in newlib.  */

#define SYS_halt      0
#define       SYS_Fopen       1
#define       SYS_Fclose      2
#define       SYS_Fread       3
#define       SYS_Fwrite      6
#define       SYS_Fseek       9
#define       SYS_Ftell       10


enum MMIX_filemode
 {
   TextRead = 0,
   TextWrite = 1,
   BinaryRead = 2,
   BinaryWrite = 3,
   BinaryReadWrite = 4
 };

#define N_MMIX_FILEHANDLES 32

/* We store a bitmap of allocated filehandles
   _MMIX_allocated_filehandle[fileno] in an array.  There are 32 of them.
   Indexes 0, 1 and 2 are allocated from start.  The reason we keep track
   of them is that *we* have to allocate a filehandle when opening a file.
   Had we got a filehandle from the simulator, we wouldn't have to keep
   track of it.  A value of 0 denotes a free handle.  */
extern unsigned char _MMIX_allocated_filehandle[N_MMIX_FILEHANDLES];

/* We use this file-handle number as a temporary; not used by usual file
   I/O.  */
#define TMPFNO 127

/* Simulator call with one argument.  Also used for zero-argument calls;
   pass a zero as ARG1.  */
#define TRAP1i(FUN, ARG1)                             \
 ({ long ret_;                                                \
    __asm__ ("TRAP 0,%1,%2\n\tSET %0,$255"            \
           : "=r" (ret_) : "i" (FUN), "i" (ARG1)      \
           : "memory");                               \
    ret_;                                             \
 })

/* Helper macros to cope with the file-handle parameter to the simulator
   being *constant*.  We support up to 32 simultaneously open files.  */
#define I3f(FUN, ARG1, N, ARGS)                                       \
 if (ARG1 == N)                                                       \
   __asm__ ("SET $255,%3\n\tTRAP 0,%1,%2\n\tSET %0,$255"      \
          : "=r" (ret_) : "i" (FUN), "i" (N), "r" (ARGS)      \
          : "memory")

/* Using if:s rather than switches to help GCC optimize the rest away.  */
#define DO32(FUN, ARG1, ARGS)                 \
    I3f (FUN, ARG1, 0, ARGS);                 \
    else I3f (FUN, ARG1, 1, ARGS);            \
    else I3f (FUN, ARG1, 2, ARGS);            \
    else I3f (FUN, ARG1, 3, ARGS);            \
    else I3f (FUN, ARG1, 4, ARGS);            \
    else I3f (FUN, ARG1, 5, ARGS);            \
    else I3f (FUN, ARG1, 6, ARGS);            \
    else I3f (FUN, ARG1, 7, ARGS);            \
    else I3f (FUN, ARG1, 8, ARGS);            \
    else I3f (FUN, ARG1, 9, ARGS);            \
    else I3f (FUN, ARG1, 10, ARGS);           \
    else I3f (FUN, ARG1, 11, ARGS);           \
    else I3f (FUN, ARG1, 12, ARGS);           \
    else I3f (FUN, ARG1, 13, ARGS);           \
    else I3f (FUN, ARG1, 14, ARGS);           \
    else I3f (FUN, ARG1, 15, ARGS);           \
    else I3f (FUN, ARG1, 16, ARGS);           \
    else I3f (FUN, ARG1, 17, ARGS);           \
    else I3f (FUN, ARG1, 18, ARGS);           \
    else I3f (FUN, ARG1, 19, ARGS);           \
    else I3f (FUN, ARG1, 20, ARGS);           \
    else I3f (FUN, ARG1, 21, ARGS);           \
    else I3f (FUN, ARG1, 22, ARGS);           \
    else I3f (FUN, ARG1, 23, ARGS);           \
    else I3f (FUN, ARG1, 24, ARGS);           \
    else I3f (FUN, ARG1, 25, ARGS);           \
    else I3f (FUN, ARG1, 26, ARGS);           \
    else I3f (FUN, ARG1, 27, ARGS);           \
    else I3f (FUN, ARG1, 28, ARGS);           \
    else I3f (FUN, ARG1, 29, ARGS);           \
    else I3f (FUN, ARG1, 30, ARGS);           \
    else I3f (FUN, ARG1, 31, ARGS);           \
    else                                      \
      {                                               \
        errno = EBADF;                                \
      return -1;                              \
      }

#define TRAP1f(FUN, ARG1)                     \
 ({ long ret_;                                        \
    DO32 (FUN, ARG1, 0);                      \
    ret_;                                     \
 })

#define TRAP2f(FUN, ARG1, ARG2)                       \
 ({ long ret_;                                        \
    DO32 (FUN, ARG1, ARG2);                   \
    ret_;                                     \
 })

#define TRAP3f(FUN, ARG1, ARG2, ARG3)                         \
 ({ long ret_;                                                        \
    unsigned long args_[]                                     \
      = { (unsigned long) (ARG2), (unsigned long) (ARG3) };   \
    DO32 (FUN, ARG1, args_);                                  \
    ret_;                                                     \
 })

#ifndef __GNUC__
/* Probably will not happen.  Nevertheless...  */
# define UNIMPLEMENTED(MSG)
#else
# define UNIMPLEMENTED(MSG) UNIMPLEMENTEDi MSG
# define UNIMPLEMENTEDi(MSG, ARGS...)                                 \
 do {                                                                 \
     char buf[2000];                                                  \
     sprintf (buf, "UNIMPLEMENTED %s in %s\n", __FUNCTION__, __FILE__);       \
     write (2, buf, strlen (buf));                                    \
     sprintf (buf, MSG , ##ARGS);                                     \
     write (2, buf, strlen (buf));                                    \
     write (2, "\n", 1);                                              \
 } while (0)
#endif