/*
* 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.adaptive.controller;
import org.jikesrvm.classloader.NormalMethod;
import org.jikesrvm.compilers.common.CompiledMethod;
/**
* A recompilation choice represents an action (or a set of actions)
* that can be considered by the controller's analytic model.
*/
abstract class RecompilationChoice {
//--- Interface ---
/**
* What is the cost of selecting this recompilation choice?
*
* @param meth The method being considered for recompilation.
* @return The expected cost of executing this recompilation choice
*/
abstract double getCost(NormalMethod meth);
/**
* What is the benefit of executing this recompilation choice, given
* the estimated future time for the method if nothing changes?
*
* @param prevCompiler The previous compiler
* @param futureExecutionTime The expected future execution time of
* the method if left running with the previous compiler.
* @return The expected future execution time if this choice were selected
*/
abstract double getFutureExecutionTime(int prevCompiler, double futureExecutionTime);
/**
* Return a controller plan that will start this recompilation choice
* in action.
*
* @param cmpMethod The method in question
* @param prevCompiler The previous compiler
* @param prevTimeFormethod The estimated future time had nothing been done
* @param bestActionTime The estimated total time implementing this choice
* @param bestCost The estimated compilation cost implementing this choice
* @return The controller plan implementing this recompilation choice
*/
abstract ControllerPlan makeControllerPlan(CompiledMethod cmpMethod, int prevCompiler, double prevTimeFormethod,
double bestActionTime, double bestCost);
}