com.friz.instruction.visitor.impl.SubtractionVisitor.java Source code

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Here is the source code for com.friz.instruction.visitor.impl.SubtractionVisitor.java

Source

/**
 * Copyright (c) 2015 Kyle Friz
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package com.friz.instruction.visitor.impl;

import org.objectweb.asm.Opcodes;
import org.objectweb.asm.tree.InsnNode;

import com.friz.instruction.tree.arith.ArithmeticInstruction;
import com.friz.instruction.utility.InstructionUtil;
import com.friz.instruction.visitor.InstructionVisitor;

/**
 * @author Kyle Friz
 * @since  Mar 12, 2016
 */
public class SubtractionVisitor extends InstructionVisitor {

    @Override
    public void visitArithmetic(ArithmeticInstruction arithmetic) {
        if (arithmetic.isSubtraction()) {
            if (InstructionUtil.isStaticPush(arithmetic.second())) {
                // var - #
                // switch var - -# to var + #
                if (arithmetic.isInt()) {
                    int val = InstructionUtil.getNumericPush(arithmetic.second()).intValue();
                    int valv = Math.abs(val);
                    if (val != valv) {
                        arithmetic.set(new InsnNode(Opcodes.IADD));
                        arithmetic.replace(InstructionUtil.createNumericPush(valv), false);
                        count++;
                    }
                } else if (arithmetic.isLong()) {
                    long val = InstructionUtil.getNumericPush(arithmetic.second()).longValue();
                    long valv = Math.abs(val);
                    if (val != valv) {
                        arithmetic.set(new InsnNode(Opcodes.LADD));
                        arithmetic.replace(InstructionUtil.createNumericPush(valv), false);
                        count++;
                    }
                } else if (arithmetic.isFloat()) {
                    float val = InstructionUtil.getNumericPush(arithmetic.second()).floatValue();
                    float valv = Math.abs(val);
                    if (val != valv) {
                        arithmetic.set(new InsnNode(Opcodes.FADD));
                        arithmetic.replace(InstructionUtil.createNumericPush(valv), false);
                        count++;
                    }
                } else if (arithmetic.isDouble()) {
                    double val = InstructionUtil.getNumericPush(arithmetic.second()).doubleValue();
                    double valv = Math.abs(val);
                    if (val != valv) {
                        arithmetic.set(new InsnNode(Opcodes.DADD));
                        arithmetic.replace(InstructionUtil.createNumericPush(valv), false);
                        count++;
                    }
                }
            }
        }
    }

    @Override
    public void results() {
        System.out.println("Adjusted " + count + " subtraction logic instructions.");
    }

    @Override
    public void reset() {
        count = 0;
    }

}