/*- * Copyright (c) 1990, 1993 * The Regents of the University of California. 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. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. */ #include <TargetConditionals.h> #include <sys/cdefs.h> __FBSDID("$FreeBSD: src/lib/libc/string/ffsll.c,v 1.1 2008/11/03 10:22:19 kib Exp $"); #include <strings.h> /* * Find First Set bit */ int ffsll(long long mask) { #if __has_builtin(__builtin_ffsll) return __builtin_ffsll(mask); #elif __has_builtin(__builtin_ctzll) if (mask == 0) return (0); return __builtin_ctzll(mask) + 1; #else int bit; if (mask == 0) return (0); for (bit = 1; !(mask & 1); bit++) mask = (unsigned long long)mask >> 1; return (bit); #endif } #if VARIANT_DYLD && TARGET_IPHONE_SIMULATOR int ffsl(long mask) { #if __has_builtin(__builtin_ffsl) return __builtin_ffsl(mask); #elif __has_builtin(__builtin_ctzl) if (mask == 0) return (0); return __builtin_ctzl(mask) + 1; #else int bit; if (mask == 0) return (0); for (bit = 1; !(mask & 1); bit++) mask = (unsigned long)mask >> 1; return (bit); #endif } int ffs(int mask) { #if __has_builtin(__builtin_ffs) return __builtin_ffs(mask); #elif __has_builtin(__builtin_ctz) if (mask == 0) return (0); return __builtin_ctz(mask) + 1; #else int bit; if (mask == 0) return (0); for (bit = 1; !(mask & 1); bit++) mask = (unsigned)mask >> 1; return (bit); #endif } #endif