/*

 * 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

fls_impl(uint64_t bits)

{

	int i = 1;

	uint32_t bits32;

	if (bits == 0)

		return (0);

	if ((bits32 = (uint32_t)(bits >> 32)) != 0)

		i += 32;

	else

		bits32 = (uint32_t)bits;

	if ((bits32 & 0xffff0000) != 0) {

		bits32 >>= 16;

		i += 16;

	}

	if ((bits32 & 0xff00) != 0) {

		bits32 >>= 8;

		i += 8;

	}

	if ((bits32 & 0xf0) != 0) {

		bits32 >>= 4;

		i += 4;

	}

	if ((bits32 & 0xc) != 0) {

		bits32 >>= 2;

		i += 2;

	}

	if ((bits32 & 0x2) != 0)

		i += 1;

	return (i);

}

int

fls(int bits)

{

	return (fls_impl((uint64_t)(uint_t)bits));

}

int

flsl(long bits)

{

	return (fls_impl((uint64_t)(ulong_t)bits));

}

int

flsll(long long bits)

{

	return (fls_impl((uint64_t)(u_longlong_t)bits));

}