diff options
Diffstat (limited to 'kernel/arch/m68k/lib/ashrdi3.c')
-rw-r--r-- | kernel/arch/m68k/lib/ashrdi3.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/kernel/arch/m68k/lib/ashrdi3.c b/kernel/arch/m68k/lib/ashrdi3.c new file mode 100644 index 000000000..1d59345f3 --- /dev/null +++ b/kernel/arch/m68k/lib/ashrdi3.c @@ -0,0 +1,58 @@ +/* ashrdi3.c extracted from gcc-2.7.2/libgcc2.c which is: */ +/* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc. + +This file is part of GNU CC. + +GNU CC is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU CC is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. */ + +#define BITS_PER_UNIT 8 + +typedef int SItype __attribute__ ((mode (SI))); +typedef unsigned int USItype __attribute__ ((mode (SI))); +typedef int DItype __attribute__ ((mode (DI))); +typedef int word_type __attribute__ ((mode (__word__))); + +struct DIstruct {SItype high, low;}; + +typedef union +{ + struct DIstruct s; + DItype ll; +} DIunion; + +DItype +__ashrdi3 (DItype u, word_type b) +{ + DIunion w; + word_type bm; + DIunion uu; + + if (b == 0) + return u; + + uu.ll = u; + + bm = (sizeof (SItype) * BITS_PER_UNIT) - b; + if (bm <= 0) + { + /* w.s.high = 1..1 or 0..0 */ + w.s.high = uu.s.high >> (sizeof (SItype) * BITS_PER_UNIT - 1); + w.s.low = uu.s.high >> -bm; + } + else + { + USItype carries = (USItype)uu.s.high << bm; + w.s.high = uu.s.high >> b; + w.s.low = ((USItype)uu.s.low >> b) | carries; + } + + return w.ll; +} |