ARM SWI

[Vijay Deep]

hi all

	Can anyone tell what does %1, %2, %a3 mean in the following line
"mov r0, %1; mov r1, %2; swi %a3; mov %0, r0". It occurs in the function
below :

do_AngelSWI (int reason, void * arg)
{
  int value;
  //It enters here
  asm volatile ("mov r0, %1; mov r1, %2; swi %a3; mov %0, r0"
       : "=r" (value) /* Outputs */
       : "r" (reason), "r" (arg), "i" (AngelSWI) /* Inputs */
       : "r0", "r1", "r2", "r3", "ip", "lr", "memory", "cc"
                /* Clobbers r0 and r1, and lr if in supervisor mode */);
                /* Accordingly to page 13-77 of ARM DUI 0040D other
registers
                   can also be clobbered.  Some memory positions may also
be
                   changed by a system call, so they should not be kept in
                   registers. Note: we are assuming the manual is right
and
                   Angel is respecting the APCS.  */
  return value;
}

Thanks in advance
Regards
Vijay Deep