arch/.unmaintained/m68k-native/exec/userstate.s

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 /*****************************************************************************
   7
   8     NAME
   9
  10         AROS_LH1(void, UserState,
  11
  12     SYNOPSIS
  13         AROS_LHA(APTR, sysStack, D0),
  14
  15     LOCATION
  16         struct ExecBase *, SysBase, 26, Exec)
  17
  18     FUNCTION
  19         Return to user mode after a call to SuperState().
  20
  21     INPUTS
  22         sysStack - The returncode from SuperState().
  23
  24     RESULT
  25
  26     NOTES
  27
  28     EXAMPLE
  29
  30     BUGS
  31
  32     SEE ALSO
  33         SuperState(), Supervisor()
  34
  35     INTERNALS
  36
  37     HISTORY
  38
  39 ******************************************************************************/
  40
  41         #include "machine.i"
  42
  43         .text
  44         .balign 4
  45         .globl  AROS_SLIB_ENTRY(UserState,Exec)
  46         .type   AROS_SLIB_ENTRY(UserState,Exec),@function
  47 AROS_SLIB_ENTRY(UserState,Exec):
  48         /* simply return if argument is NULL */
  49         tst.l   d0
  50         bne     nonzero
  51         rts
  52 nonzero:
  53         /* Transfer sp */
  54         move.l  sp,usp
  55
  56         /* Set old supervisor sp */
  57         move.l  d0,sp
  58
  59         /* And return. This jumps directly to a rts. */
  60         rte
  61