Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
at v2.6.29 59 lines 1.6 kB view raw
1/* 2 * File: arch/blackfin/lib/ashrdi3.c 3 * Based on: 4 * Author: 5 * 6 * Created: 7 * Description: 8 * 9 * Modified: 10 * Copyright 2004-2006 Analog Devices Inc. 11 * 12 * Bugs: Enter bugs at http://blackfin.uclinux.org/ 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License as published by 16 * the Free Software Foundation; either version 2 of the License, or 17 * (at your option) any later version. 18 * 19 * This program is distributed in the hope that it will be useful, 20 * but WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22 * GNU General Public License for more details. 23 * 24 * You should have received a copy of the GNU General Public License 25 * along with this program; if not, see the file COPYING, or write 26 * to the Free Software Foundation, Inc., 27 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 28 */ 29 30#include "gcclib.h" 31 32#ifdef CONFIG_ARITHMETIC_OPS_L1 33DItype __ashrdi3(DItype u, word_type b)__attribute__((l1_text)); 34#endif 35 36DItype __ashrdi3(DItype u, word_type b) 37{ 38 DIunion w; 39 word_type bm; 40 DIunion uu; 41 42 if (b == 0) 43 return u; 44 45 uu.ll = u; 46 47 bm = (sizeof(SItype) * BITS_PER_UNIT) - b; 48 if (bm <= 0) { 49 /* w.s.high = 1..1 or 0..0 */ 50 w.s.high = uu.s.high >> (sizeof(SItype) * BITS_PER_UNIT - 1); 51 w.s.low = uu.s.high >> -bm; 52 } else { 53 USItype carries = (USItype) uu.s.high << bm; 54 w.s.high = uu.s.high >> b; 55 w.s.low = ((USItype) uu.s.low >> b) | carries; 56 } 57 58 return w.ll; 59}