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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
*/
#include "lint.h"
#include <string.h>
#include <strings.h>
#include <sys/types.h>
static int
ffs_impl(uint64_t bits)
{
int i = 1;
uint32_t bits32;
if (bits == 0)
return (0);
if ((bits32 = (uint32_t)bits) == 0) {
bits32 = (uint32_t)(bits >> 32);
i += 32;
}
if ((bits32 & 0xffff) == 0) {
bits32 >>= 16;
i += 16;
}
if ((bits32 & 0xff) == 0) {
bits32 >>= 8;
i += 8;
}
if ((bits32 & 0xf) == 0) {
bits32 >>= 4;
i += 4;
}
if ((bits32 & 0x3) == 0) {
bits32 >>= 2;
i += 2;
}
if ((bits32 & 0x1) == 0)
i += 1;
return (i);
}
int
ffs(int bits)
{
return (ffs_impl((uint64_t)(uint_t)bits));
}
int
ffsl(long bits)
{
return (ffs_impl((uint64_t)(ulong_t)bits));
}
int
ffsll(long long bits)
{
return (ffs_impl((uint64_t)(u_longlong_t)bits));
}
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