Embedded Matters: GCC ARM porting


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/* vi: set sw=4 ts=4: */
/* syscall for arm/uClibc
 *
 * Copyright (C) 2002 by Erik Andersen 
 *
 * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
 */

#include 
#include 
#include 
#include 


long syscall(long sysnum, long a, long b, long c, long d, long e, long f)
{
#if !defined(__thumb__)
 register long _r0 __asm__("r0")=(long)(sysnum);
 register long _r6 __asm__("r6")=(long)(f);
 register long _r5 __asm__("r5")=(long)(e);
 register long _r4 __asm__("r4")=(long)(d);
 register long _r3 __asm__("r3")=(long)(c);
 register long _r2 __asm__("r2")=(long)(b);
 register long _r1 __asm__("r1")=(long)(a);
 __asm__ __volatile__(
   "swi %1"
   : "=r"(_r0)
   : "i"(__NR_syscall), "r"(_r0), "r"(_r1),
   "r"(_r2), "r"(_r3), "r"(_r4), "r"(_r5),
   "r"(_r6)
   : "memory");
#else
 register long _r7 __asm__("r7")=(long)(sysnum);
 register long _r5 __asm__("r5")=(long)(f);
 register long _r4 __asm__("r4")=(long)(e);
 register long _r3 __asm__("r3")=(long)(d);
 register long _r2 __asm__("r2")=(long)(c);
 register long _r1 __asm__("r1")=(long)(b);
 register long _r0 __asm__("r0")=(long)(a);
 __asm__ __volatile__(
   "swi 0"
   : "=r"(_r0)
   : "r"(_r0), "r"(_r1), "r"(_r2), "r"(_r3),
   "r"(_r4), "r"(_r5), "r"(_r7)
   : "memory");
#endif
 if(_r0 >=(unsigned long) -4095) {
  long err = _r0;
  (*__errno_location())=(-err);
  _r0=(unsigned long) -1;
 }
 return (long) _r0;
}