WALA/com.ibm.wala.core/src/com/ibm/wala/ssa/SSAArrayLengthInstruction.java

123 lines
2.9 KiB
Java

/*******************************************************************************
* 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.ssa;
/**
* SSA instruction representing v_x := arraylength v_y
*/
public abstract class SSAArrayLengthInstruction extends SSAInstruction {
private final int result;
private final int arrayref;
protected SSAArrayLengthInstruction(int index, int result, int arrayref) {
super(index);
this.result = result;
this.arrayref = arrayref;
}
@Override
public SSAInstruction copyForSSA(SSAInstructionFactory insts, int[] defs, int[] uses) throws IllegalArgumentException {
if (defs != null && defs.length != 1) {
throw new IllegalArgumentException();
}
if (uses != null && uses.length != 1) {
throw new IllegalArgumentException();
}
return insts.ArrayLengthInstruction(iindex, defs == null ? result : defs[0], uses == null ? arrayref : uses[0]);
}
@Override
public String toString(SymbolTable symbolTable) {
return getValueString(symbolTable, result) + " = arraylength " + getValueString(symbolTable, arrayref);
}
/**
* @see com.ibm.wala.ssa.SSAInstruction#visit(IVisitor)
*/
@Override
public void visit(IVisitor v) throws NullPointerException {
v.visitArrayLength(this);
}
/**
* @see com.ibm.wala.ssa.SSAInstruction#getDef()
*/
@Override
public int getDef() {
return result;
}
@Override
public boolean hasDef() {
return true;
}
@Override
public int getDef(int i) {
if (i != 0) {
throw new IllegalArgumentException("invalid i " + i);
}
return result;
}
@Override
public int getNumberOfDefs() {
return 1;
}
public int getArrayRef() {
return arrayref;
}
/**
* @see com.ibm.wala.ssa.SSAInstruction#getNumberOfUses()
*/
@Override
public int getNumberOfUses() {
return 1;
}
/**
* @see com.ibm.wala.ssa.SSAInstruction#getUse(int)
*/
@Override
public int getUse(int j) {
if (j != 0) {
throw new IllegalArgumentException("invalid j: " + j);
}
return arrayref;
}
@Override
public int hashCode() {
return arrayref * 7573 + result * 563;
}
/*
* @see com.ibm.wala.ssa.Instruction#isPEI()
*/
@Override
public boolean isPEI() {
return true;
}
/*
* @see com.ibm.wala.ssa.Instruction#isFallThrough()
*/
@Override
public boolean isFallThrough() {
return true;
}
}