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 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 #include <linux/compiler.h> 17 #include <linux/export.h> 18 19 #define BITS_PER_UNIT 8 20 21 typedef int SItype __attribute__ ((mode (SI))); 22 typedef unsigned int USItype __attribute__ ((mode (SI))); 23 typedef int DItype __attribute__ ((mode (DI))); 24 typedef int word_type __attribute__ ((mode (__word__))); 25 26 struct DIstruct {SItype high, low;}; 27 28 typedef union 29 { 30 struct DIstruct s; 31 DItype ll; 32 } DIunion; 33 34 DItype 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 } 62 EXPORT_SYMBOL(__ashrdi3); 63