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/*
* SPDX-FileCopyrightText: 2015 Wind River Systems, Inc.
* SPDX-FileCopyrightText: 2017 Oticon A/S
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef _BLE_MESH_FFS_H_
#define _BLE_MESH_FFS_H_
#include "mesh/types.h"
#include "mesh/compiler.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
*
* @brief find most significant bit set in a 32-bit word
*
* This routine finds the first bit set starting from the most significant bit
* in the argument passed in and returns the index of that bit. Bits are
* numbered starting at 1 from the least significant bit. A return value of
* zero indicates that the value passed is zero.
*
* @return most significant bit set, 0 if @a op is 0
*/
static ALWAYS_INLINE unsigned int find_msb_set(uint32_t op)
{
if (op == 0) {
return 0;
}
return 32 - __builtin_clz(op);
}
/**
*
* @brief find least significant bit set in a 32-bit word
*
* This routine finds the first bit set starting from the least significant bit
* in the argument passed in and returns the index of that bit. Bits are
* numbered starting at 1 from the least significant bit. A return value of
* zero indicates that the value passed is zero.
*
* @return least significant bit set, 0 if @a op is 0
*/
static ALWAYS_INLINE unsigned int find_lsb_set(uint32_t op)
{
return __builtin_ffs(op);
}
#ifdef __cplusplus
}
#endif
#endif /* _BLE_MESH_FFS_H_ */
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