arch/.unmaintained/m68k-emul/enable.s

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Exec function Enable
   6     Lang: english
   7 */
   8
   9 /******************************************************************************
  10
  11     NAME
  12         AROS_LH0(void, Enable,
  13
  14     LOCATION
  15         struct ExecBase *, SysBase, 21, Exec)
  16
  17     FUNCTION
  18
  19     INPUTS
  20
  21     RESULT
  22
  23     NOTES
  24
  25     EXAMPLE
  26
  27     BUGS
  28
  29     SEE ALSO
  30
  31     INTERNALS
  32
  33     HISTORY
  34
  35 ******************************************************************************/
  36
  37         #include "machine.i"
  38
  39         .text
  40         .balign 16
  41         .globl  AROS_SLIB_ENTRY(Enable,Exec)
  42         .type   AROS_SLIB_ENTRY(Enable,Exec),@function
  43 AROS_SLIB_ENTRY(Enable,Exec):
  44 #if !UseRegisterArgs
  45         /* Preserve all registers */
  46         move.l  %a6,-(%sp)
  47
  48         /* Get SysBase */
  49         move.l  8(%sp),%a6
  50 #endif
  51
  52         /* Decrement and test IDNestCnt */
  53         subq.b  #1,IDNestCnt(%a6)
  54         jbpl    .noswch
  55         jbsr    AROS_CSYMNAME(os_enable)
  56
  57         /* return if there are no delayed switches pending. */
  58         btst    #7,AttnResched+1(%a6)
  59         jbeq    .noswch
  60
  61         /* if TDNestCnt is not -1 taskswitches are still forbidden */
  62         tst.b   TDNestCnt(%a6)
  63         jbpl    .noswch
  64
  65         /* Unset delayed switch bit and do the delayed switch */
  66         bclr    #7,AttnResched+1(%a6)
  67 #if !UseRegisterArgs
  68         move.l  %a6,-(%sp)
  69 #endif
  70         jsr     Switch(%a6)
  71 #if !UseRegisterArgs
  72         addq.w  #4,%sp
  73 #endif
  74
  75         /* all done. */
  76 .noswch:
  77 #if !UseRegisterArgs
  78         move.l  (%sp)+,%a6
  79 #endif
  80         rts