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Diffstat (limited to 'arch/blackfin/lib/lshrdi3.c')
-rw-r--r-- | arch/blackfin/lib/lshrdi3.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/arch/blackfin/lib/lshrdi3.c b/arch/blackfin/lib/lshrdi3.c new file mode 100644 index 000000000000..84b9c5592220 --- /dev/null +++ b/arch/blackfin/lib/lshrdi3.c @@ -0,0 +1,72 @@ +/* + * File: arch/blackfin/lib/lshrdi3.c + * Based on: + * Author: + * + * Created: + * Description: + * + * Modified: + * Copyright 2004-2006 Analog Devices Inc. + * + * Bugs: Enter bugs at http://blackfin.uclinux.org/ + * + * This program 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 of the License, or + * (at your option) any later version. + * + * This program 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see the file COPYING, or write + * to the Free Software Foundation, Inc., + * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#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; + +#ifdef CONFIG_ARITHMETIC_OPS_L1 +DItype __lshrdi3(DItype u, word_type b)__attribute__((l1_text)); +#endif + +DItype __lshrdi3(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 = 0; + w.s.low = (USItype) uu.s.high >> -bm; + } else { + USItype carries = (USItype) uu.s.high << bm; + w.s.high = (USItype) uu.s.high >> b; + w.s.low = ((USItype) uu.s.low >> b) | carries; + } + + return w.ll; +} |