OpenCloudOS-Kernel/lib/ashrdi3.c

47 lines
1.2 KiB
C

/*
* 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.
*/
#include <linux/export.h>
#include <linux/libgcc.h>
long long notrace __ashrdi3(long long u, word_type b)
{
DWunion uu, w;
word_type bm;
if (b == 0)
return u;
uu.ll = u;
bm = 32 - b;
if (bm <= 0) {
/* w.s.high = 1..1 or 0..0 */
w.s.high =
uu.s.high >> 31;
w.s.low = uu.s.high >> -bm;
} else {
const unsigned int carries = (unsigned int) uu.s.high << bm;
w.s.high = uu.s.high >> b;
w.s.low = ((unsigned int) uu.s.low >> b) | carries;
}
return w.ll;
}
EXPORT_SYMBOL(__ashrdi3);