OpcodeUtils.java

/*
 * fb-contrib - Auxiliary detectors for Java programs
 * Copyright (C) 2005-2017 Kevin Lubick
 * Copyright (C) 2005-2017 Dave Brosius
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package com.mebigfatguy.fbcontrib.utils;

import java.util.BitSet;

import org.apache.bcel.Constants;

/**
 * a collection of static methods for categorizing opcodes into groups
 */
public final class OpcodeUtils implements Constants {

    private static final BitSet BRANCH_OPS = new BitSet();
    private static final BitSet INVOKE_OPS = new BitSet();

    static {
        BRANCH_OPS.set(GOTO);
        BRANCH_OPS.set(GOTO_W);
        BRANCH_OPS.set(IF_ACMPEQ);
        BRANCH_OPS.set(IF_ACMPNE);
        BRANCH_OPS.set(IF_ICMPEQ);
        BRANCH_OPS.set(IF_ICMPGE);
        BRANCH_OPS.set(IF_ICMPGT);
        BRANCH_OPS.set(IF_ICMPLE);
        BRANCH_OPS.set(IF_ICMPLT);
        BRANCH_OPS.set(IF_ICMPNE);
        BRANCH_OPS.set(IFEQ);
        BRANCH_OPS.set(IFGE);
        BRANCH_OPS.set(IFGT);
        BRANCH_OPS.set(IFLE);
        BRANCH_OPS.set(IFLT);
        BRANCH_OPS.set(IFNE);
        BRANCH_OPS.set(IFNONNULL);
        BRANCH_OPS.set(IFNULL);

        INVOKE_OPS.set(INVOKEVIRTUAL);
        INVOKE_OPS.set(INVOKESTATIC);
        INVOKE_OPS.set(INVOKEINTERFACE);
        INVOKE_OPS.set(INVOKESPECIAL);
        INVOKE_OPS.set(INVOKEDYNAMIC);
    }

    private OpcodeUtils() {
    }

    public static boolean isALoad(int seen) {
        return (seen == ALOAD) || ((seen >= ALOAD_0) && (seen <= ALOAD_3));
    }

    public static boolean isAStore(int seen) {
        return (seen == ASTORE) || ((seen >= ASTORE_0) && (seen <= ASTORE_3));
    }

    public static boolean isILoad(int seen) {
        return (seen == ILOAD) || ((seen >= ILOAD_0) && (seen <= ILOAD_3));
    }

    public static boolean isIStore(int seen) {
        return (seen == ISTORE) || ((seen >= ISTORE_0) && (seen <= ISTORE_3));
    }

    public static boolean isLLoad(int seen) {
        return (seen == LLOAD) || ((seen >= LLOAD_0) && (seen <= LLOAD_3));
    }

    public static boolean isLStore(int seen) {
        return (seen == LSTORE) || ((seen >= LSTORE_0) && (seen <= LSTORE_3));
    }

    public static boolean isFLoad(int seen) {
        return (seen == FLOAD) || ((seen >= FLOAD_0) && (seen <= FLOAD_3));
    }

    public static boolean isFStore(int seen) {
        return (seen == FSTORE) || ((seen >= FSTORE_0) && (seen <= FSTORE_3));
    }

    public static boolean isDLoad(int seen) {
        return (seen == DLOAD) || ((seen >= DLOAD_0) && (seen <= DLOAD_3));
    }

    public static boolean isDStore(int seen) {
        return (seen == DSTORE) || ((seen >= DSTORE_0) && (seen <= DSTORE_3));
    }

    public static boolean isLoad(int seen) {
        return isALoad(seen) || isILoad(seen) || isLLoad(seen) || isFLoad(seen) || isDLoad(seen);
    }

    public static boolean isStore(int seen) {
        return isAStore(seen) || isIStore(seen) || isLStore(seen) || isFStore(seen) || isDStore(seen);
    }

    public static boolean isInvoke(int seen) {
        return INVOKE_OPS.get(seen);
    }

    public static boolean isStandardInvoke(int seen) {
        return (seen == INVOKESPECIAL) || (seen == INVOKEINTERFACE) || (seen == INVOKEVIRTUAL) || (seen == INVOKESTATIC);
    }

    public static boolean isBranch(int seen) {
        return BRANCH_OPS.get(seen);
    }

    public static boolean isReturn(int seen) {
        return ((seen == ARETURN) || (seen == IRETURN) || (seen == LRETURN) || (seen == FRETURN) || (seen == DRETURN) || (seen == RETURN));
    }

}