/*
* This file is part of the Jikes RVM project (http://jikesrvm.org).
*
* This file is licensed to You under the Eclipse Public License (EPL);
* You may not use this file except in compliance with the License. You
* may obtain a copy of the License at
*
* http://www.opensource.org/licenses/eclipse-1.0.php
*
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership.
*/
package org.jikesrvm.compilers.opt.ir.operand;
import org.jikesrvm.runtime.RuntimeEntrypoints;
/**
* Encode the semantic reason for a trap instruction.
*
* @see Operand
*/
public final class TrapCodeOperand extends Operand {
/**
* The trap code.
*/
private final byte trapCode;
/**
* Create a trap code operand
* @param why the trap code
*/
private TrapCodeOperand(byte why) {
trapCode = why;
}
/**
* Create a trap code operand for a null pointer check
* @return the newly created trap code operand
*/
public static TrapCodeOperand NullPtr() {
return new TrapCodeOperand((byte) RuntimeEntrypoints.TRAP_NULL_POINTER);
}
/**
* Create a trap code operand for an array bounds check
* @return the newly created trap code operand
*/
public static TrapCodeOperand ArrayBounds() {
return new TrapCodeOperand((byte) RuntimeEntrypoints.TRAP_ARRAY_BOUNDS);
}
/**
* Create a trap code operand for a divide by zero check
* @return the newly created trap code operand
*/
public static TrapCodeOperand DivByZero() {
return new TrapCodeOperand((byte) RuntimeEntrypoints.TRAP_DIVIDE_BY_ZERO);
}
/**
* Create a trap code operand for a stack overflow
* @return the newly created trap code operand
*/
public static TrapCodeOperand StackOverflow() {
return new TrapCodeOperand((byte) RuntimeEntrypoints.TRAP_STACK_OVERFLOW);
}
/**
* Create a trap code operand for a check cast
* @return the newly created trap code operand
*/
public static TrapCodeOperand CheckCast() {
return new TrapCodeOperand((byte) RuntimeEntrypoints.TRAP_CHECKCAST);
}
/**
* Create a trap code operand for a must implement
* @return the newly created trap code operand
*/
public static TrapCodeOperand MustImplement() {
return new TrapCodeOperand((byte) RuntimeEntrypoints.TRAP_MUST_IMPLEMENT);
}
/**
* Create a trap code operand for a must implement
* @return the newly created trap code operand
*/
public static TrapCodeOperand StoreCheck() {
return new TrapCodeOperand((byte) RuntimeEntrypoints.TRAP_STORE_CHECK);
}
/**
* Create a trap code operand for a regeneration trap
* @return the newly created trap code operand
*/
public static TrapCodeOperand Regenerate() {
return new TrapCodeOperand((byte) RuntimeEntrypoints.TRAP_REGENERATE);
}
/**
* Does the operand represent a null pointer check?
* @return <code>true</code> if it does and <code>false</code>
* if it does not
*/
public boolean isNullPtr() {
return trapCode == RuntimeEntrypoints.TRAP_NULL_POINTER;
}
/**
* Does the operand represent an array bounds check ?
* @return <code>true</code> if it does and <code>false</code>
* if it does not
*/
public boolean isArrayBounds() {
return trapCode == RuntimeEntrypoints.TRAP_ARRAY_BOUNDS;
}
/**
* Does the operand represent a divide by zero check?
* @return <code>true</code> if it does and <code>false</code>
* if it does not
*/
public boolean isDivByZero() {
return trapCode == RuntimeEntrypoints.TRAP_DIVIDE_BY_ZERO;
}
/**
* Does the operand represent a stack overflow check?
* @return <code>true</code> if it does and <code>false</code>
* if it does not
*/
public boolean isStackOverflow() {
return trapCode == RuntimeEntrypoints.TRAP_STACK_OVERFLOW;
}
/**
* Does the operand represent a check cast?
* @return <code>true</code> if it does and <code>false</code>
* if it does not
*/
public boolean isCheckCast() {
return trapCode == RuntimeEntrypoints.TRAP_CHECKCAST;
}
/**
* Does the operand represent a must implement trap?
* @return <code>true</code> if it does and <code>false</code>
* if it does not
*/
public boolean isDoesImplement() {
return trapCode == RuntimeEntrypoints.TRAP_MUST_IMPLEMENT;
}
/**
* Does the operand represent an array store check?
* @return <code>true</code> if it does and <code>false</code>
* if it does not
*/
public boolean isStoreCheck() {
return trapCode == RuntimeEntrypoints.TRAP_STORE_CHECK;
}
/**
* Does the operand represent a regeneration trap?
* @return <code>true</code> if it does and <code>false</code>
* if it does not
*/
public boolean isRegenerate() {
return trapCode == RuntimeEntrypoints.TRAP_REGENERATE;
}
/**
* Return a new operand that is semantically equivalent to <code>this</code>.
*
* @return a copy of <code>this</code>
*/
public Operand copy() {
return new TrapCodeOperand(trapCode);
}
/**
* Are two operands semantically equivalent?
*
* @param op other operand
* @return <code>true</code> if <code>this</code> and <code>op</code>
* are semantically equivalent or <code>false</code>
* if they are not.
*/
public boolean similar(Operand op) {
return op instanceof TrapCodeOperand && ((TrapCodeOperand) op).trapCode == trapCode;
}
/**
* Returns the string representation of this operand.
*
* @return a string representation of this operand.
*/
public String toString() {
switch (trapCode) {
case RuntimeEntrypoints.TRAP_NULL_POINTER:
return "<NULL PTR>";
case RuntimeEntrypoints.TRAP_ARRAY_BOUNDS:
return "<ARRAY BOUNDS>";
case RuntimeEntrypoints.TRAP_DIVIDE_BY_ZERO:
return "<DIV BY ZERO>";
case RuntimeEntrypoints.TRAP_STACK_OVERFLOW:
return "<STACK OVERFLOW>";
case RuntimeEntrypoints.TRAP_CHECKCAST:
return "<CLASSCAST>";
case RuntimeEntrypoints.TRAP_MUST_IMPLEMENT:
return "<MUST IMPLEMENT>";
case RuntimeEntrypoints.TRAP_STORE_CHECK:
return "<OBJARRAY STORE CHECK>";
case RuntimeEntrypoints.TRAP_REGENERATE:
return "<REGENERATE>";
default:
return "<UNKNOWN TRAP>";
}
}
/**
* Return the numeric value representing the trap code; this is
* used by the assembler (on Intel) when generating code.
*
* @return Numeric value representing this trap code
*/
public int getTrapCode() {
return trapCode;
}
}