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 4This file is part of GNU CC. 5 6GNU CC is free software; you can redistribute it and/or modify 7it under the terms of the GNU General Public Licence as published by 8the Free Software Foundation; either version 2, or (at your option) 9any later version. 10 11GNU CC is distributed in the hope that it will be useful, 12but WITHOUT ANY WARRANTY; without even the implied warranty of 13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14GNU General Public Licence for more details. 15 16You should have received a copy of the GNU General Public Licence 17along with GNU CC; see the file COPYING. If not, write to 18the Free Software Foundation, 59 Temple Place - Suite 330, 19Boston, MA 02111-1307, USA. */ 20 21#define BITS_PER_UNIT 8 22 23typedef int SItype __attribute__((mode(SI))); 24typedef unsigned int USItype __attribute__((mode(SI))); 25typedef int DItype __attribute__((mode(DI))); 26typedef int word_type __attribute__((mode(__word__))); 27 28struct DIstruct { 29 SItype low; 30 SItype high; 31}; 32 33union DIunion { 34 struct DIstruct s; 35 DItype ll; 36}; 37 38DItype __lshrdi3(DItype u, word_type b) 39{ 40 union DIunion w; 41 word_type bm; 42 union DIunion uu; 43 44 if (b == 0) 45 return u; 46 47 uu.ll = u; 48 49 bm = (sizeof(SItype) * BITS_PER_UNIT) - b; 50 if (bm <= 0) { 51 w.s.high = 0; 52 w.s.low = (USItype) uu.s.high >> -bm; 53 } else { 54 USItype carries = (USItype) uu.s.high << bm; 55 w.s.high = (USItype) uu.s.high >> b; 56 w.s.low = ((USItype) uu.s.low >> b) | carries; 57 } 58 59 return w.ll; 60} 61