001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 package org.apache.commons.nabla.forward.arithmetic; 018 019 import org.apache.commons.nabla.DifferentiationException; 020 import org.apache.commons.nabla.forward.analysis.InstructionsTransformer; 021 import org.apache.commons.nabla.forward.analysis.MethodDifferentiator; 022 import org.objectweb.asm.Opcodes; 023 import org.objectweb.asm.Type; 024 import org.objectweb.asm.tree.AbstractInsnNode; 025 import org.objectweb.asm.tree.InsnList; 026 import org.objectweb.asm.tree.InsnNode; 027 import org.objectweb.asm.tree.MethodInsnNode; 028 029 /** Differentiation transformer for DMUL instructions. 030 * @version $Id$ 031 */ 032 public class DMulTransformer implements InstructionsTransformer { 033 034 /** Name of the {@link org.apache.commons.math3.analysis.differentiation.DerivativeStructure} method corresponding to the multiplication. */ 035 private static final String MULTIPLY_METHOD = "multiply"; 036 037 /** Indicator for top stack element conversion. */ 038 private final boolean stack0Converted; 039 040 /** Indicator for next to top stack element conversion. */ 041 private final boolean stack1Converted; 042 043 /** Simple constructor. 044 * @param stack0Converted if true, the top level stack element has already been converted 045 * @param stack1Converted if true, the next to top level stack element has already been converted 046 */ 047 public DMulTransformer(final boolean stack0Converted, final boolean stack1Converted) { 048 this.stack0Converted = stack0Converted; 049 this.stack1Converted = stack1Converted; 050 } 051 052 /** {@inheritDoc} */ 053 public InsnList getReplacement(final AbstractInsnNode insn, 054 final MethodDifferentiator methodDifferentiator) 055 throws DifferentiationException { 056 057 final InsnList list = new InsnList(); 058 059 if (stack1Converted) { 060 if (stack0Converted) { 061 list.add(new MethodInsnNode(Opcodes.INVOKEVIRTUAL, DS_TYPE.getInternalName(), 062 MULTIPLY_METHOD, 063 Type.getMethodDescriptor(DS_TYPE, DS_TYPE))); 064 } else { 065 list.add(new MethodInsnNode(Opcodes.INVOKEVIRTUAL, DS_TYPE.getInternalName(), 066 MULTIPLY_METHOD, 067 Type.getMethodDescriptor(DS_TYPE, Type.DOUBLE_TYPE))); 068 } 069 } else { 070 list.add(new InsnNode(Opcodes.DUP_X2)); 071 list.add(new InsnNode(Opcodes.POP)); 072 list.add(new MethodInsnNode(Opcodes.INVOKEVIRTUAL, DS_TYPE.getInternalName(), 073 MULTIPLY_METHOD, 074 Type.getMethodDescriptor(DS_TYPE, Type.DOUBLE_TYPE))); 075 } 076 077 return list; 078 079 } 080 081 }