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author | kib <kib@FreeBSD.org> | 2008-11-03 10:22:19 +0000 |
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committer | kib <kib@FreeBSD.org> | 2008-11-03 10:22:19 +0000 |
commit | 8b86595849b35ac7c26977f1b8206c1678c9b5bb (patch) | |
tree | 1736b8d9ed54635f5f6a78cea9b9e57e008ff489 /lib/libc/string/ffsll.c | |
parent | 2f0fec26d1f00542c759ebd153e7c91686217bc4 (diff) | |
download | FreeBSD-src-8b86595849b35ac7c26977f1b8206c1678c9b5bb.zip FreeBSD-src-8b86595849b35ac7c26977f1b8206c1678c9b5bb.tar.gz |
Add the ffsll and flsll functions. These are ffs and fls operating
on long long arguments.
Reviewed by: bde (previous version, that included asm implementation
for all ffs and fls functions on i386 and amd64)
MFC after: 2 weeks
Diffstat (limited to 'lib/libc/string/ffsll.c')
-rw-r--r-- | lib/libc/string/ffsll.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/lib/libc/string/ffsll.c b/lib/libc/string/ffsll.c new file mode 100644 index 0000000..59e03bc --- /dev/null +++ b/lib/libc/string/ffsll.c @@ -0,0 +1,48 @@ +/*- + * Copyright (c) 1990, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <strings.h> + +/* + * Find First Set bit + */ +int +ffsll(long long mask) +{ + int bit; + + if (mask == 0) + return (0); + for (bit = 1; !(mask & 1); bit++) + mask = (unsigned long long)mask >> 1; + return (bit); +} |