1 /* 2 * Copyright (c) 2012, 2014, 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 package org.graalvm.compiler.replacements; 24 25 import org.graalvm.compiler.api.replacements.ClassSubstitution; 26 import org.graalvm.compiler.api.replacements.MethodSubstitution; 27 import org.graalvm.compiler.replacements.nodes.BitScanForwardNode; 28 import org.graalvm.compiler.replacements.nodes.BitScanReverseNode; 29 30 @ClassSubstitution(Integer.class) 31 public class IntegerSubstitutions { 32 33 @MethodSubstitution 34 public static int numberOfLeadingZeros(int i) { 35 if (i == 0) { 36 return 32; 37 } 38 return 31 - BitScanReverseNode.unsafeScan(i); 39 } 40 41 @MethodSubstitution 42 public static int numberOfTrailingZeros(int i) { 43 if (i == 0) { 44 return 32; 45 } 46 return BitScanForwardNode.unsafeScan(i); 47 } 48 }