glibc/sysdeps/x86_64/ffsll.c
Paul Eggert 2b778ceb40 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
2021-01-02 12:17:34 -08:00

43 lines
1.3 KiB
C

/* ffsll -- find first set bit in a word, counted from least significant end.
For AMD x86-64.
This file is part of the GNU C Library.
Copyright (C) 1991-2021 Free Software Foundation, Inc.
Contributed by Ulrich Drepper <drepper@cygnus.com>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#define ffsl __something_else
#include <string.h>
#undef ffsll
int
ffsll (long long int x)
{
long long int cnt;
long long int tmp;
asm ("bsfq %2,%0\n" /* Count low bits in X and store in %1. */
"cmoveq %1,%0\n" /* If number was zero, use -1 as result. */
: "=&r" (cnt), "=r" (tmp) : "rm" (x), "1" (-1));
return cnt + 1;
}
#ifndef __ILP32__
#undef ffsl
weak_alias (ffsll, ffsl)
#endif