/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * This file is available under and governed by the GNU General Public

 * License version 2 only, as published by the Free Software Foundation.

 * However, the following notice accompanied the original version of this

 * file:

 *

 * ASM: a very small and fast Java bytecode manipulation framework

 * Copyright (c) 2000-2011 INRIA, France Telecom

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. Neither the name of the copyright holders nor the names of its

 *    contributors may be used to endorse or promote products derived from

 *    this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF

 * THE POSSIBILITY OF SUCH DAMAGE.

 */

package jdk.internal.org.objectweb.asm.tree.analysis;

import java.util.HashSet;

import java.util.List;

import java.util.Set;

import jdk.internal.org.objectweb.asm.Opcodes;

import jdk.internal.org.objectweb.asm.Type;

import jdk.internal.org.objectweb.asm.tree.AbstractInsnNode;

import jdk.internal.org.objectweb.asm.tree.FieldInsnNode;

import jdk.internal.org.objectweb.asm.tree.InvokeDynamicInsnNode;

import jdk.internal.org.objectweb.asm.tree.LdcInsnNode;

import jdk.internal.org.objectweb.asm.tree.MethodInsnNode;

/**

 * An {@link Interpreter} for {@link SourceValue} values.

 *

 * @author Eric Bruneton

 */

public class SourceInterpreter extends Interpreter<SourceValue> implements

        Opcodes {

    public SourceInterpreter() {

        super(ASM5);

    }

    protected SourceInterpreter(final int api) {

        super(api);

    }

    @Override

    public SourceValue newValue(final Type type) {

        if (type == Type.VOID_TYPE) {

            return null;

        }

        return new SourceValue(type == null ? 1 : type.getSize());

    }

    @Override

    public SourceValue newOperation(final AbstractInsnNode insn) {

        int size;

        switch (insn.getOpcode()) {

        case LCONST_0:

        case LCONST_1:

        case DCONST_0:

        case DCONST_1:

            size = 2;

            break;

        case LDC:

            Object cst = ((LdcInsnNode) insn).cst;

            size = cst instanceof Long || cst instanceof Double ? 2 : 1;

            break;

        case GETSTATIC:

            size = Type.getType(((FieldInsnNode) insn).desc).getSize();

            break;

        default:

            size = 1;

        }

        return new SourceValue(size, insn);

    }

    @Override

    public SourceValue copyOperation(final AbstractInsnNode insn,

            final SourceValue value) {

        return new SourceValue(value.getSize(), insn);

    }

    @Override

    public SourceValue unaryOperation(final AbstractInsnNode insn,

            final SourceValue value) {

        int size;

        switch (insn.getOpcode()) {

        case LNEG:

        case DNEG:

        case I2L:

        case I2D:

        case L2D:

        case F2L:

        case F2D:

        case D2L:

            size = 2;

            break;

        case GETFIELD:

            size = Type.getType(((FieldInsnNode) insn).desc).getSize();

            break;

        default:

            size = 1;

        }

        return new SourceValue(size, insn);

    }

    @Override

    public SourceValue binaryOperation(final AbstractInsnNode insn,

            final SourceValue value1, final SourceValue value2) {

        int size;

        switch (insn.getOpcode()) {

        case LALOAD:

        case DALOAD:

        case LADD:

        case DADD:

        case LSUB:

        case DSUB:

        case LMUL:

        case DMUL:

        case LDIV:

        case DDIV:

        case LREM:

        case DREM:

        case LSHL:

        case LSHR:

        case LUSHR:

        case LAND:

        case LOR:

        case LXOR:

            size = 2;

            break;

        default:

            size = 1;

        }

        return new SourceValue(size, insn);

    }

    @Override

    public SourceValue ternaryOperation(final AbstractInsnNode insn,

            final SourceValue value1, final SourceValue value2,

            final SourceValue value3) {

        return new SourceValue(1, insn);

    }

    @Override

    public SourceValue naryOperation(final AbstractInsnNode insn,

            final List<? extends SourceValue> values) {

        int size;

        int opcode = insn.getOpcode();

        if (opcode == MULTIANEWARRAY) {

            size = 1;

        } else {

            String desc = (opcode == INVOKEDYNAMIC) ? ((InvokeDynamicInsnNode) insn).desc

                    : ((MethodInsnNode) insn).desc;

            size = Type.getReturnType(desc).getSize();

        }

        return new SourceValue(size, insn);

    }

    @Override

    public void returnOperation(final AbstractInsnNode insn,

            final SourceValue value, final SourceValue expected) {

    }

    @Override

    public SourceValue merge(final SourceValue d, final SourceValue w) {

        if (d.insns instanceof SmallSet && w.insns instanceof SmallSet) {

            Set<AbstractInsnNode> s = ((SmallSet<AbstractInsnNode>) d.insns)

                    .union((SmallSet<AbstractInsnNode>) w.insns);

            if (s == d.insns && d.size == w.size) {

                return d;

            } else {

                return new SourceValue(Math.min(d.size, w.size), s);

            }

        }

        if (d.size != w.size || !d.insns.containsAll(w.insns)) {

            HashSet<AbstractInsnNode> s = new HashSet<AbstractInsnNode>();

            s.addAll(d.insns);

            s.addAll(w.insns);

            return new SourceValue(Math.min(d.size, w.size), s);

        }

        return d;

    }

}