1 /* lshrdi3.c extracted from gcc-2.7.2/libgcc2.c which is: */ 2 /* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc. 3 4 This file is part of GNU CC. 5 6 GNU CC is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 GNU CC 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 GNU CC; see the file COPYING. If not, write to 18 the Free Software Foundation, 59 Temple Place - Suite 330, 19 Boston, MA 02111-1307, USA. */ 20 21 #define BITS_PER_UNIT 8 22 23 typedef int SItype __attribute__ ((mode (SI))); 24 typedef unsigned int USItype __attribute__ ((mode (SI))); 25 typedef int DItype __attribute__ ((mode (DI))); 26 typedef int word_type __attribute__ ((mode (__word__))); 27 28 struct DIstruct {SItype high, low;}; 29 30 typedef union 31 { 32 struct DIstruct s; 33 DItype ll; 34 } DIunion; 35 36 DItype 37 __lshrdi3 (DItype u, word_type b) 38 { 39 DIunion w; 40 word_type bm; 41 DIunion uu; 42 43 if (b == 0) 44 return u; 45 46 uu.ll = u; 47 48 bm = (sizeof (SItype) * BITS_PER_UNIT) - b; 49 if (bm <= 0) 50 { 51 w.s.high = 0; 52 w.s.low = (USItype)uu.s.high >> -bm; 53 } 54 else 55 { 56 USItype carries = (USItype)uu.s.high << bm; 57 w.s.high = (USItype)uu.s.high >> b; 58 w.s.low = ((USItype)uu.s.low >> b) | carries; 59 } 60 61 return w.ll; 62 } 63