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
This commit is contained in:
Konstantin Belousov 2008-11-03 10:22:19 +00:00
parent 6f41f432e1
commit 4a723bd20c
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=184587
6 changed files with 124 additions and 8 deletions

View File

@ -44,8 +44,10 @@ void bzero(void *, size_t); /* LEGACY */
int ffs(int) __pure2;
#ifdef __BSD_VISIBLE
int ffsl(long) __pure2;
int ffsll(long long) __pure2;
int fls(int) __pure2;
int flsl(long) __pure2;
int flsll(long long) __pure2;
#endif
char *index(const char *, int) __pure; /* LEGACY */
char *rindex(const char *, int) __pure; /* LEGACY */

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@ -6,8 +6,8 @@
CFLAGS+= -I${.CURDIR}/locale
# machine-independent string sources
MISRCS+=bcmp.c bcopy.c bzero.c ffs.c ffsl.c fls.c flsl.c index.c memccpy.c \
memchr.c memrchr.c memcmp.c \
MISRCS+=bcmp.c bcopy.c bzero.c ffs.c ffsl.c ffsll.c fls.c flsl.c flsll.c \
index.c memccpy.c memchr.c memrchr.c memcmp.c \
memcpy.c memmem.c memmove.c memset.c rindex.c stpcpy.c strcasecmp.c \
strcat.c strchr.c strcmp.c strcoll.c strcpy.c strcspn.c strdup.c \
strerror.c strlcat.c strlcpy.c strlen.c strmode.c strncat.c strncmp.c \
@ -38,6 +38,8 @@ MAN+= bcmp.3 bcopy.3 bstring.3 bzero.3 ffs.3 index.3 memccpy.3 memchr.3 \
MLINKS+=ffs.3 ffsl.3
MLINKS+=ffs.3 fls.3
MLINKS+=ffs.3 flsl.3
MLINKS+=ffs.3 ffsll.3
MLINKS+=ffs.3 flsll.3
MLINKS+=index.3 rindex.3
MLINKS+=memchr.3 memrchr.3
MLINKS+=strcasecmp.3 strncasecmp.3

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@ -78,6 +78,8 @@ FBSD_1.0 {
};
FBSD_1.1 {
ffsll;
flsll;
memrchr;
};

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@ -30,14 +30,16 @@
.\" @(#)ffs.3 8.2 (Berkeley) 4/19/94
.\" $FreeBSD$
.\"
.Dd October 12, 2006
.Dd October 26, 2008
.Dt FFS 3
.Os
.Sh NAME
.Nm ffs ,
.Nm ffsl ,
.Nm ffsll ,
.Nm fls ,
.Nm flsl
.Nm flsl ,
.Nm flsll
.Nd find first or last bit set in a bit string
.Sh LIBRARY
.Lb libc
@ -48,14 +50,19 @@
.Ft int
.Fn ffsl "long value"
.Ft int
.Ft int
.Fn ffsll "long long value"
.Fn fls "int value"
.Ft int
.Fn flsl "long value"
.Ft int
.Fn flsll "long long value"
.Sh DESCRIPTION
The
.Fn ffs
and
.Fn ffs ,
.Fn ffsl
and
.Fn ffsll
functions find the first bit set
(beginning with the least significant bit)
in
@ -63,9 +70,10 @@ in
and return the index of that bit.
.Pp
The
.Fn fls
and
.Fn fls ,
.Fn flsl
and
.Fn flsll
functions find the last bit set in
.Fa value
and return the index of that bit.
@ -95,3 +103,9 @@ and
.Fn flsl
functions appeared in
.Fx 5.3 .
The
.Fn ffsll
and
.Fn flsll
functions appeared in
.Fx 8.0 .

48
lib/libc/string/ffsll.c Normal file
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@ -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);
}

48
lib/libc/string/flsll.c Normal file
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@ -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 Last Set bit
*/
int
flsll(long long mask)
{
int bit;
if (mask == 0)
return (0);
for (bit = 1; mask != 1; bit++)
mask = (unsigned long long)mask >> 1;
return (bit);
}