/***
 * ASM: a very small and fast Java bytecode manipulation framework
 * Copyright (c) 2000-2007 INRIA, France Telecom
 * 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.
 * 3. Neither the name of the copyright holders 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
 */
package alterrs.asm.tree.analysis;

import java.util.Set;

import alterrs.asm.tree.AbstractInsnNode;

/**
 * A {@link Value} that is represented by its type in a two types type system.
 * This type system distinguishes the ONEWORD and TWOWORDS types.
 * 
 * @author Eric Bruneton
 */
public class SourceValue implements Value {

	/**
	 * The size of this value.
	 */
	public final int size;

	/**
	 * The instructions that can produce this value. For example, for the Java
	 * code below, the instructions that can produce the value of <tt>i</tt> at
	 * line 5 are the txo ISTORE instructions at line 1 and 3:
	 * <p/>
	 * 
	 * <pre>
	 * 1: i = 0;
	 * 2: if (...) {
	 * 3:   i = 1;
	 * 4: }
	 * 5: return i;
	 * </pre>
	 * <p/>
	 * This field is a set of {@link alterrs.asm.tree.AbstractInsnNode} objects.
	 */
	public final Set insns;

	public SourceValue(final int size) {
		this(size, SmallSet.EMPTY_SET);
	}

	public SourceValue(final int size, final AbstractInsnNode insn) {
		this.size = size;
		this.insns = new SmallSet(insn, null);
	}

	public SourceValue(final int size, final Set insns) {
		this.size = size;
		this.insns = insns;
	}

	public int getSize() {
		return size;
	}

	public boolean equals(final Object value) {
		if (!(value instanceof SourceValue)) {
			return false;
		}
		SourceValue v = (SourceValue) value;
		return size == v.size && insns.equals(v.insns);
	}

	public int hashCode() {
		return insns.hashCode();
	}
}
