d6b50a1d3f
nxstyle fixes to pass the CI checks Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
83 lines
2.6 KiB
C
83 lines
2.6 KiB
C
/****************************************************************************
|
|
* libs/libc/string/lib_ffsll.c
|
|
*
|
|
* Licensed to the Apache Software Foundation (ASF) under one or more
|
|
* contributor license agreements. See the NOTICE file distributed with
|
|
* this work for additional information regarding copyright ownership. The
|
|
* ASF licenses this file to you under the Apache License, Version 2.0 (the
|
|
* "License"); you may not use this file except in compliance with the
|
|
* License. You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
* License for the specific language governing permissions and limitations
|
|
* under the License.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <nuttx/compiler.h>
|
|
#include <strings.h>
|
|
|
|
/****************************************************************************
|
|
* Pre-processor Definitions
|
|
****************************************************************************/
|
|
|
|
#define NBITS (8 * sizeof(unsigned long long))
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
#ifdef CONFIG_HAVE_LONG_LONG
|
|
|
|
/****************************************************************************
|
|
* Name: ffsll
|
|
*
|
|
* Description:
|
|
* The ffsll() function will find the first bit set (beginning with the
|
|
* least significant bit) in i, and return the index of that bit. Bits are
|
|
* numbered starting at one (the least significant bit).
|
|
*
|
|
* Returned Value:
|
|
* The ffsll() function will return the index of the first bit set. If j is
|
|
* 0, then ffsll() will return 0.
|
|
*
|
|
****************************************************************************/
|
|
|
|
int ffsll(long long j)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (j != 0)
|
|
{
|
|
#ifdef CONFIG_HAVE_BUILTIN_CTZ
|
|
/* Count trailing zeros function can be used to implement ffs. */
|
|
|
|
ret = __builtin_ctzll(j) + 1;
|
|
#else
|
|
unsigned long long value = (unsigned long long)j;
|
|
int bitno;
|
|
|
|
for (bitno = 1; bitno <= NBITS; bitno++, value >>= 1)
|
|
{
|
|
if ((value & 1) != 0)
|
|
{
|
|
ret = bitno;
|
|
break;
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
#endif
|