sdcc/device/lib/mcs51/crtxpopr0.asm

   1 ;--------------------------------------------------------------------------
   2 ;  crtxpopbits.asm - C run-time: pop bits and other registers from xstack
   3 ;
   4 ;  Copyright (C) 2009, Maarten Brock
   5 ;
   6 ;  This library is free software; you can redistribute it and/or modify it
   7 ;  under the terms of the GNU General Public License as published by the
   8 ;  Free Software Foundation; either version 2, or (at your option) any
   9 ;  later version.
  10 ;
  11 ;  This library is distributed in the hope that it will be useful,
  12 ;  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 ;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14 ;  GNU General Public License for more details.
  15 ;
  16 ;  You should have received a copy of the GNU General Public License
  17 ;  along with this library; see the file COPYING. If not, write to the
  18 ;  Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
  19 ;   MA 02110-1301, USA.
  20 ;
  21 ;  As a special exception, if you link this library with other files,
  22 ;  some of which are compiled with SDCC, to produce an executable,
  23 ;  this library does not by itself cause the resulting executable to
  24 ;  be covered by the GNU General Public License. This exception does
  25 ;  not however invalidate any other reasons why the executable file
  26 ;  might be covered by the GNU General Public License.
  27 ;--------------------------------------------------------------------------
  28
  29 ;--------------------------------------------------------
  30 ; overlayable bit register bank
  31 ;--------------------------------------------------------
  32         .area BIT_BANK  (REL,OVR,DATA)
  33 bits:
  34         .ds 1
  35
  36         ar0 = 0x00
  37         ar1 = 0x01
  38
  39         .area HOME    (CODE)
  40
  41 ; Pop registers r0..r7 & bits from xstack (r0 always)
  42 ; Expect mask in B
  43 ___sdcc_xpop_regs_r0::
  44         mov     r0,_spx
  45         dec     r0
  46         movx    a,@r0           ;pop R0
  47         ljmp    ___sdcc_xpop