/* * Copyright 2011-2015 Samy Al Bahra. * Copyright 2011 David Joseph. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Several of these are from: http://graphics.stanford.edu/~seander/bithacks.html */ #define CK_INTERNAL_LOG_0 (0xAAAAAAAA) #define CK_INTERNAL_LOG_1 (0xCCCCCCCC) #define CK_INTERNAL_LOG_2 (0xF0F0F0F0) #define CK_INTERNAL_LOG_3 (0xFF00FF00) #define CK_INTERNAL_LOG_4 (0xFFFF0000) CK_CC_INLINE static uint32_t ck_internal_log(uint32_t v) { uint32_t r = (v & CK_INTERNAL_LOG_0) != 0; r |= ((v & CK_INTERNAL_LOG_4) != 0) << 4; r |= ((v & CK_INTERNAL_LOG_3) != 0) << 3; r |= ((v & CK_INTERNAL_LOG_2) != 0) << 2; r |= ((v & CK_INTERNAL_LOG_1) != 0) << 1; return (r); } CK_CC_INLINE static uint32_t ck_internal_power_2(uint32_t v) { --v; v |= v >> 1; v |= v >> 2; v |= v >> 4; v |= v >> 8; v |= v >> 16; return (++v); } CK_CC_INLINE static unsigned long ck_internal_max(unsigned long x, unsigned long y) { return x ^ ((x ^ y) & -(x < y)); } CK_CC_INLINE static uint64_t ck_internal_max_64(uint64_t x, uint64_t y) { return x ^ ((x ^ y) & -(x < y)); } CK_CC_INLINE static uint32_t ck_internal_max_32(uint32_t x, uint32_t y) { return x ^ ((x ^ y) & -(x < y)); }