#region License Information /* HeuristicLab * Copyright (C) Heuristic and Evolutionary Algorithms Laboratory (HEAL) * * This file is part of HeuristicLab. * * HeuristicLab is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * HeuristicLab is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with HeuristicLab. If not, see . */ #endregion using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding; namespace HeuristicLab.Problems.DataAnalysis.Symbolic { public class InterpreterState { private readonly double[] argumentStack; private int argumentStackPointer; private readonly Instruction[] code; public int ProgramCounter { get; set; } public bool InLaggedContext { get; set; } public InterpreterState(Instruction[] code, int argumentStackSize) { this.code = code; this.ProgramCounter = 0; this.InLaggedContext = false; if (argumentStackSize > 0) { this.argumentStack = new double[argumentStackSize]; } this.argumentStackPointer = 0; } public void Reset() { this.ProgramCounter = 0; this.argumentStackPointer = 0; this.InLaggedContext = false; } public Instruction NextInstruction() { return code[ProgramCounter++]; } // skips a whole branch public void SkipInstructions() { int i = 1; while (i > 0) { i += NextInstruction().nArguments; i--; } } private void Push(double val) { argumentStack[argumentStackPointer++] = val; } private double Pop() { return argumentStack[--argumentStackPointer]; } public void CreateStackFrame(double[] argValues) { // push in reverse order to make indexing easier for (int i = argValues.Length - 1; i >= 0; i--) { argumentStack[argumentStackPointer++] = argValues[i]; } Push(argValues.Length); } public void RemoveStackFrame() { int size = (int)Pop(); argumentStackPointer -= size; } public double GetStackFrameValue(ushort index) { // layout of stack: // [0] <- argumentStackPointer // [StackFrameSize = N + 1] // [Arg0] <- argumentStackPointer - 2 - 0 // [Arg1] <- argumentStackPointer - 2 - 1 // [...] // [ArgN] <- argumentStackPointer - 2 - N // return argumentStack[argumentStackPointer - index - 2]; } } }