sdcc/device/lib/mos6502/_modsint.s

   1 ;-------------------------------------------------------------------------
   2 ;   _modsint.s - routine for division of 16 bit signed int
   3 ;
   4 ;   Copyright (C) 1998, Ullrich von Bassewitz
   5 ;   Copyright (C) 2022, Gabriele Gorla
   6 ;
   7 ;   This library is free software; you can redistribute it and/or modify it
   8 ;   under the terms of the GNU General Public License as published by the
   9 ;   Free Software Foundation; either version 2, or (at your option) any
  10 ;   later version.
  11 ;
  12 ;   This library is distributed in the hope that it will be useful,
  13 ;   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 ;   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 ;   GNU General Public License for more details.
  16 ;
  17 ;   You should have received a copy of the GNU General Public License
  18 ;   along with this library; see the file COPYING. If not, write to the
  19 ;   Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
  20 ;   MA 02110-1301, USA.
  21 ;
  22 ;   As a special exception, if you link this library with other files,
  23 ;   some of which are compiled with SDCC, to produce an executable,
  24 ;   this library does not by itself cause the resulting executable to
  25 ;   be covered by the GNU General Public License. This exception does
  26 ;   not however invalidate any other reasons why the executable file
  27 ;   might be covered by the GNU General Public License.
  28 ;-------------------------------------------------------------------------
  29
  30         .module _modsint
  31
  32 ;--------------------------------------------------------
  33 ; exported symbols
  34 ;--------------------------------------------------------
  35         .globl __modsint
  36
  37 ;--------------------------------------------------------
  38 ; local aliases
  39 ;--------------------------------------------------------
  40         .define res "___SDCC_m6502_ret0"
  41         .define den "__divsint_PARM_2"
  42         .define rem "___SDCC_m6502_ret2"
  43         .define s1  "___SDCC_m6502_ret4"
  44         .define s2  "___SDCC_m6502_ret5"
  45
  46 ;--------------------------------------------------------
  47 ; code
  48 ;--------------------------------------------------------
  49         .area CODE
  50
  51 __modsint:
  52         jsr     ___sdivmod16
  53         lda     *rem+0
  54         ldx     *rem+1
  55         ldy     *s1
  56         bpl     pos
  57         jmp     ___negax
  58 pos:
  59         rts