/* * Copyright (c) 2015, Wind River Systems, Inc. * Copyright (c) 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(u32_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(u32_t op) { return __builtin_ffs(op); } #ifdef __cplusplus } #endif #endif /* _BLE_MESH_FFS_H_ */