/*******************************************************************************
* Copyright (c) 2002,2006 IBM Corporation.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package com.ibm.wala.shrikeBT;
/**
* This class represents the ?aload instructions.
*/
final public class ArrayLoadInstruction extends Instruction implements IArrayLoadInstruction {
protected ArrayLoadInstruction(short opcode) {
super(opcode);
}
private final static ArrayLoadInstruction[] preallocated = preallocate();
private static ArrayLoadInstruction[] preallocate() {
ArrayLoadInstruction[] r = new ArrayLoadInstruction[OP_saload - OP_iaload + 2];
for (short i = OP_iaload; i <= OP_saload; i++) {
r[i - OP_iaload] = new ArrayLoadInstruction(i);
}
r[OP_saload - OP_iaload + 1] = r[OP_baload - OP_iaload];
return r;
}
public static ArrayLoadInstruction make(String type) throws IllegalArgumentException {
int i = Util.getTypeIndex(type);
if (i < 0 || i > TYPE_boolean_index) {
throw new IllegalArgumentException("Invalid type " + type + " for ArrayLoadInstruction");
}
return preallocated[i];
}
@Override
public boolean equals(Object o) {
if (o instanceof ArrayLoadInstruction) {
ArrayLoadInstruction i = (ArrayLoadInstruction) o;
return i.opcode == opcode;
} else {
return false;
}
}
@Override
public int hashCode() {
return opcode + 9109101;
}
@Override
public int getPoppedCount() {
return 2;
}
@Override
public String toString() {
return "ArrayLoad(" + getType() + ")";
}
@Override
public String getPushedType(String[] types) throws IllegalArgumentException {
if (types == null) {
return getType();
} else {
if (types.length <= 1) {
throw new IllegalArgumentException("types.length <= 1");
}
String t = types[1];
if (t == null) {
throw new IllegalArgumentException("types[1] cannot be null");
}
if (t.startsWith("[")) {
return t.substring(1);
} else if (t.equals(TYPE_null)) {
return TYPE_null;
} else {
return TYPE_unknown;
}
}
}
@Override
public byte getPushedWordSize() {
return Util.getWordSize(getType());
}
@Override
public String getType() {
return Constants.indexedTypes[opcode - OP_iaload];
}
@Override
public void visit(IInstruction.Visitor v) throws NullPointerException {
v.visitArrayLoad(this);
}
@Override
public boolean isPEI() {
return true;
}
/**
* Java bytecode does not permit this.
* @see com.ibm.wala.shrikeBT.IMemoryOperation#isAddressOf()
*/
@Override
public boolean isAddressOf() {
return false;
}
}