--- /dev/null 2017-01-22 10:16:57.869617664 -0800 +++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.common/src/org/graalvm/compiler/core/common/util/IntList.java 2017-02-15 16:57:15.844103891 -0800 @@ -0,0 +1,163 @@ +/* + * Copyright (c) 2010, 2011, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ +package org.graalvm.compiler.core.common.util; + +import java.util.Arrays; + +/** + * An expandable and indexable list of {@code int}s. + * + * This class avoids the boxing/unboxing incurred by {@code ArrayList}. + */ +public final class IntList { + + private int[] array; + private int size; + + /** + * Creates an int list with a specified initial capacity. + * + * @param initialCapacity + */ + public IntList(int initialCapacity) { + array = new int[initialCapacity]; + } + + /** + * Creates an int list with a specified initial array. + * + * @param array the initial array used for the list (no copy is made) + * @param initialSize the initial {@linkplain #size() size} of the list (must be less than or + * equal to {@code array.length} + */ + public IntList(int[] array, int initialSize) { + assert initialSize <= array.length; + this.array = array; + this.size = initialSize; + } + + /** + * Makes a new int list by copying a range from a given int list. + * + * @param other the list from which a range of values is to be copied into the new list + * @param startIndex the index in {@code other} at which to start copying + * @param length the number of values to copy from {@code other} + * @return a new int list whose {@linkplain #size() size} and capacity is {@code length} + */ + public static IntList copy(IntList other, int startIndex, int length) { + return copy(other, startIndex, length, length); + } + + /** + * Makes a new int list by copying a range from a given int list. + * + * @param other the list from which a range of values is to be copied into the new list + * @param startIndex the index in {@code other} at which to start copying + * @param length the number of values to copy from {@code other} + * @param initialCapacity the initial capacity of the new int list (must be greater or equal to + * {@code length}) + * @return a new int list whose {@linkplain #size() size} is {@code length} + */ + public static IntList copy(IntList other, int startIndex, int length, int initialCapacity) { + assert initialCapacity >= length : "initialCapacity < length"; + int[] array = new int[initialCapacity]; + System.arraycopy(other.array, startIndex, array, 0, length); + return new IntList(array, length); + } + + public int size() { + return size; + } + + /** + * Appends a value to the end of this list, increasing its {@linkplain #size() size} by 1. + * + * @param value the value to append + */ + public void add(int value) { + if (size == array.length) { + int newSize = (size * 3) / 2 + 1; + array = Arrays.copyOf(array, newSize); + } + array[size++] = value; + } + + /** + * Gets the value in this list at a given index. + * + * @param index the index of the element to return + * @throws IndexOutOfBoundsException if {@code index < 0 || index >= size()} + */ + public int get(int index) { + if (index >= size) { + throw new IndexOutOfBoundsException("Index: " + index + ", Size: " + size); + } + return array[index]; + } + + /** + * Sets the size of this list to 0. + */ + public void clear() { + size = 0; + } + + /** + * Sets a value at a given index in this list. + * + * @param index the index of the element to update + * @param value the new value of the element + * @throws IndexOutOfBoundsException if {@code index < 0 || index >= size()} + */ + public void set(int index, int value) { + if (index >= size) { + throw new IndexOutOfBoundsException("Index: " + index + ", Size: " + size); + } + array[index] = value; + } + + /** + * Adjusts the {@linkplain #size() size} of this int list. + * + * If {@code newSize < size()}, the size is changed to {@code newSize}. If + * {@code newSize > size()}, sufficient 0 elements are {@linkplain #add(int) added} until + * {@code size() == newSize}. + * + * @param newSize the new size of this int list + */ + public void setSize(int newSize) { + if (newSize < size) { + size = newSize; + } else if (newSize > size) { + array = Arrays.copyOf(array, newSize); + } + } + + @Override + public String toString() { + if (array.length == size) { + return Arrays.toString(array); + } + return Arrays.toString(Arrays.copyOf(array, size)); + } +}