ashrdi3.c (1499B)
1/* ashrdi3.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 License 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 License for more details. */ 15 16#include <linux/compiler.h> 17#include <linux/export.h> 18 19#define BITS_PER_UNIT 8 20 21typedef int SItype __mode(SI); 22typedef unsigned int USItype __mode(SI); 23typedef int DItype __mode(DI); 24typedef int word_type __mode(__word__); 25 26struct DIstruct {SItype high, low;}; 27 28typedef union 29{ 30 struct DIstruct s; 31 DItype ll; 32} DIunion; 33 34DItype 35__ashrdi3 (DItype u, word_type b) 36{ 37 DIunion w; 38 word_type bm; 39 DIunion uu; 40 41 if (b == 0) 42 return u; 43 44 uu.ll = u; 45 46 bm = (sizeof (SItype) * BITS_PER_UNIT) - b; 47 if (bm <= 0) 48 { 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 } 53 else 54 { 55 USItype carries = (USItype)uu.s.high << bm; 56 w.s.high = uu.s.high >> b; 57 w.s.low = ((USItype)uu.s.low >> b) | carries; 58 } 59 60 return w.ll; 61} 62EXPORT_SYMBOL(__ashrdi3);