1 /* 2 * Copyright (c) 2016, 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 jdk.vm.ci.code; 24 25 import java.util.Arrays; 26 import java.util.Collection; 27 import java.util.Collections; 28 import java.util.Iterator; 29 import java.util.List; 30 31 /** 32 * An immutable ordered list of registers. Only required because Java lacks immutable arrays. 33 */ 34 public final class RegisterArray implements Iterable<Register> { 35 36 private final Register[] registers; 37 private int hash; 38 RegisterArray(Register... registers)39 public RegisterArray(Register... registers) { 40 this.registers = registers; 41 } 42 RegisterArray(Collection<Register> registers)43 public RegisterArray(Collection<Register> registers) { 44 this.registers = registers.toArray(new Register[registers.size()]); 45 } 46 47 /** 48 * Gets the number of registers. 49 */ size()50 public int size() { 51 return registers.length; 52 } 53 54 /** 55 * Gets the register at a given index. 56 * 57 * @param index the index of the register to retrieve 58 */ get(int index)59 public Register get(int index) { 60 return registers[index]; 61 } 62 addTo(Collection<Register> collection)63 public void addTo(Collection<Register> collection) { 64 collection.addAll(Arrays.asList(registers)); 65 } 66 67 /** 68 * Gets an immutable view of the registers as a list. 69 */ asList()70 public List<Register> asList() { 71 return Collections.unmodifiableList(Arrays.asList(registers)); 72 } 73 74 /** 75 * Gets a copy of the registers as an array. 76 */ toArray()77 public Register[] toArray() { 78 return registers.clone(); 79 } 80 81 @Override iterator()82 public Iterator<Register> iterator() { 83 return Arrays.asList(registers).iterator(); 84 } 85 86 @Override hashCode()87 public int hashCode() { 88 if (hash == 0 && registers.length > 0) { 89 hash = Arrays.hashCode(registers); 90 } 91 return hash; 92 } 93 94 @Override equals(Object obj)95 public boolean equals(Object obj) { 96 if (obj instanceof RegisterArray) { 97 return Arrays.equals(registers, ((RegisterArray) obj).registers); 98 } 99 return false; 100 } 101 102 @Override toString()103 public String toString() { 104 return Arrays.toString(registers); 105 } 106 } 107