newlib-cygwin/newlib/libc/sys/mmixware/_exit.c

32 lines
1.0 KiB
C

/* _exit for MMIXware.
Copyright (C) 2001, 2023 Hans-Peter Nilsson
Permission to use, copy, modify, and distribute this software is
freely granted, provided that the above copyright notice, this notice
and the following disclaimer are 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. */
#include <_ansi.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "sys/syscall.h"
void _exit (int n)
{
/* The return status is passed on at exit from the simulator by all
but the oldest versions of Knuth's mmixware simulator. Beware,
"TRAP 0,0,0" is the instruction corresponding to (int32_t) 0 and
the value 0 in $255 is common enough that a program crash jumping
to e.g. uninitialized memory will look like "exit (0)". */
__asm__ ("SET $255,%0\n\tTRAP 0,0,0"
: /* No outputs. */
: "r" (n)
: "memory");
__unreachable ();
}