libgcc/config/rl78/adddi3.S

   1 ;   Copyright (C) 2017-2020 Free Software Foundation, Inc.
   2 ;   Contributed by Sebastian Perta.
   3 ;
   4 ; This file is free software; you can redistribute it and/or modify it
   5 ; under the terms of the GNU General Public License as published by the
   6 ; Free Software Foundation; either version 3, or (at your option) any
   7 ; later version.
   8 ;
   9 ; This file is distributed in the hope that it will be useful, but
  10 ; WITHOUT ANY WARRANTY; without even the implied warranty of
  11 ; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12 ; General Public License for more details.
  13 ;
  14 ; Under Section 7 of GPL version 3, you are granted additional
  15 ; permissions described in the GCC Runtime Library Exception, version
  16 ; 3.1, as published by the Free Software Foundation.
  17 ;
  18 ; You should have received a copy of the GNU General Public License and
  19 ; a copy of the GCC Runtime Library Exception along with this program;
  20 ; see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  21 ; <http://www.gnu.org/licenses/>.
  22
  23
  24 #include "vregs.h"
  25
  26     .text
  27
  28 START_FUNC ___adddi3
  29
  30     movw  hl, sp       ; use HL-based addressing (allows for direct addw)
  31
  32     movw  ax, [hl+4]
  33     addw  ax, [hl+12]
  34     movw  r8, ax
  35
  36     mov   a, [hl+6]    ; middle bytes of the result are determined using 8-bit
  37     addc  a, [hl+14]   ; ADDC insns which both account for and update the carry bit
  38     mov   r10, a       ; (no ADDWC instruction is available)
  39     mov   a, [hl+7]
  40     addc  a, [hl+15]
  41     mov   r11, a
  42
  43     mov   a, [hl+8]
  44     addc  a, [hl+16]
  45     mov   r12, a
  46     mov   a, [hl+9]
  47     addc  a, [hl+17]
  48     mov   r13, a
  49
  50     movw  ax, [hl+10]
  51     sknc               ; account for the possible carry from the
  52     incw  ax           ; latest 8-bit operation
  53     addw  ax, [hl+18]
  54     movw  r14, ax
  55
  56     ret
  57
  58 END_FUNC ___adddi3