abs.s (1704B)
1;-------------------------------------------------------------------------- 2; abs.s 3; 4; Copyright (C) 2010, Philipp Klaus Krause 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 .area _CODE 30 31 .globl _abs 32 33; 12B; 86T for nonnegative arguments, 78T for negative. 34_abs: 35 pop hl 36 pop de 37 push de 38 push hl 39 xor a, a 40 ld l, a 41 ld h, a 42 sbc hl, de 43 ret P 44 ex de, hl 45 ret 46 47; 14B; 59T for nonegative arguments, 94T for negative: 48;_abs: 49; pop de 50; pop hl 51; push hl 52; push de 53; bit 7, h 54; ret Z 55; xor a, a 56; ld e, a 57; ld d, a 58; ex de, hl 59; sbc hl, de 60; ret 61