1/*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1991, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37#ifndef _SYS_BITCOUNT_H_ 38#define _SYS_BITCOUNT_H_ 39 40#include <sys/_types.h> 41 42#ifdef __POPCNT__ 43#define __bitcount64(x) __builtin_popcountll((__uint64_t)(x)) 44#define __bitcount32(x) __builtin_popcount((__uint32_t)(x)) 45#define __bitcount16(x) __builtin_popcount((__uint16_t)(x)) 46#define __bitcountl(x) __builtin_popcountl((unsigned long)(x)) 47#define __bitcount(x) __builtin_popcount((unsigned int)(x)) 48#else 49/* 50 * Population count algorithm using SWAR approach 51 * - "SIMD Within A Register". 52 */ 53static __inline __uint16_t 54__bitcount16(__uint16_t _x) 55{ 56 57 _x = (_x & 0x5555) + ((_x & 0xaaaa) >> 1); 58 _x = (_x & 0x3333) + ((_x & 0xcccc) >> 2); 59 _x = (_x + (_x >> 4)) & 0x0f0f; 60 _x = (_x + (_x >> 8)) & 0x00ff; 61 return (_x); 62} 63 64static __inline __uint32_t 65__bitcount32(__uint32_t _x) 66{ 67 68 _x = (_x & 0x55555555) + ((_x & 0xaaaaaaaa) >> 1); 69 _x = (_x & 0x33333333) + ((_x & 0xcccccccc) >> 2); 70 _x = (_x + (_x >> 4)) & 0x0f0f0f0f; 71 _x = (_x + (_x >> 8)); 72 _x = (_x + (_x >> 16)) & 0x000000ff; 73 return (_x); 74} 75 76#ifdef __LP64__ 77static __inline __uint64_t 78__bitcount64(__uint64_t _x) 79{ 80 81 _x = (_x & 0x5555555555555555) + ((_x & 0xaaaaaaaaaaaaaaaa) >> 1); 82 _x = (_x & 0x3333333333333333) + ((_x & 0xcccccccccccccccc) >> 2); 83 _x = (_x + (_x >> 4)) & 0x0f0f0f0f0f0f0f0f; 84 _x = (_x + (_x >> 8)); 85 _x = (_x + (_x >> 16)); 86 _x = (_x + (_x >> 32)) & 0x000000ff; 87 return (_x); 88} 89 90#define __bitcountl(x) __bitcount64((unsigned long)(x)) 91#else 92static __inline __uint64_t 93__bitcount64(__uint64_t _x) 94{ 95 96 return (__bitcount32(_x >> 32) + __bitcount32(_x)); 97} 98 99#define __bitcountl(x) __bitcount32((unsigned long)(x)) 100#endif 101#define __bitcount(x) __bitcount32((unsigned int)(x)) 102#endif 103 104#endif /* !_SYS_BITCOUNT_H_ */ 105