1 /* 2 * Copyright (c) 2017, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef OS_CPU_SOLARIS_SPARC_COUNT_TRAILING_ZEROS_SOLARIS_SPARC_HPP 26 #define OS_CPU_SOLARIS_SPARC_COUNT_TRAILING_ZEROS_SOLARIS_SPARC_HPP 27 28 #include "utilities/globalDefinitions.hpp" 29 30 inline unsigned count_trailing_zeros(uintx x) { 31 assert(x != 0, "precondition"); 32 // Reduce to mask with ones in all positions below the least 33 // significant set bit of x, and zeros otherwise. 34 uintx rx = (x - 1) & ~x; // sub x, 1, rx; andn rx, x, rx; 35 // Then count the set bits in the reduction. 36 uintx result; 37 __asm__(" popc %1, %0\n\t" : "=r" (result) : "r" (rx)); 38 return result; 39 } 40 41 #endif // OS_CPU_SOLARIS_SPARC_COUNT_TRAILING_ZEROS_SOLARIS_SPARC_HPP