/*

 * 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) 2000-2007 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 com.sun.xml.internal.ws.org.objectweb.asm;

/**

 * A {@link MethodVisitor} that generates methods in bytecode form. Each visit

 * method of this class appends the bytecode corresponding to the visited

 * instruction to a byte vector, in the order these methods are called.

 *

 * @author Eric Bruneton

 * @author Eugene Kuleshov

 */

class MethodWriter implements MethodVisitor {

    /**

     * Pseudo access flag used to denote constructors.

     */

    static final int ACC_CONSTRUCTOR = 262144;

    /**

     * Frame has exactly the same locals as the previous stack map frame and

     * number of stack items is zero.

     */

    static final int SAME_FRAME = 0; // to 63 (0-3f)

    /**

     * Frame has exactly the same locals as the previous stack map frame and

     * number of stack items is 1

     */

    static final int SAME_LOCALS_1_STACK_ITEM_FRAME = 64; // to 127 (40-7f)

    /**

     * Reserved for future use

     */

    static final int RESERVED = 128;

    /**

     * Frame has exactly the same locals as the previous stack map frame and

     * number of stack items is 1. Offset is bigger then 63;

     */

    static final int SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED = 247; // f7

    /**

     * Frame where current locals are the same as the locals in the previous

     * frame, except that the k last locals are absent. The value of k is given

     * by the formula 251-frame_type.

     */

    static final int CHOP_FRAME = 248; // to 250 (f8-fA)

    /**

     * Frame has exactly the same locals as the previous stack map frame and

     * number of stack items is zero. Offset is bigger then 63;

     */

    static final int SAME_FRAME_EXTENDED = 251; // fb

    /**

     * Frame where current locals are the same as the locals in the previous

     * frame, except that k additional locals are defined. The value of k is

     * given by the formula frame_type-251.

     */

    static final int APPEND_FRAME = 252; // to 254 // fc-fe

    /**

     * Full frame

     */

    static final int FULL_FRAME = 255; // ff

    /**

     * Indicates that the stack map frames must be recomputed from scratch. In

     * this case the maximum stack size and number of local variables is also

     * recomputed from scratch.

     *

     * @see #compute

     */

    private static final int FRAMES = 0;

    /**

     * Indicates that the maximum stack size and number of local variables must

     * be automatically computed.

     *

     * @see #compute

     */

    private static final int MAXS = 1;

    /**

     * Indicates that nothing must be automatically computed.

     *

     * @see #compute

     */

    private static final int NOTHING = 2;

    /**

     * Next method writer (see {@link ClassWriter#firstMethod firstMethod}).

     */

    MethodWriter next;

    /**

     * The class writer to which this method must be added.

     */

    final ClassWriter cw;

    /**

     * Access flags of this method.

     */

    private int access;

    /**

     * The index of the constant pool item that contains the name of this

     * method.

     */

    private final int name;

    /**

     * The index of the constant pool item that contains the descriptor of this

     * method.

     */

    private final int desc;

    /**

     * The descriptor of this method.

     */

    private final String descriptor;

    /**

     * The signature of this method.

     */

    String signature;

    /**

     * If not zero, indicates that the code of this method must be copied from

     * the ClassReader associated to this writer in <code>cw.cr</code>. More

     * precisely, this field gives the index of the first byte to copied from

     * <code>cw.cr.b</code>.

     */

    int classReaderOffset;

    /**

     * If not zero, indicates that the code of this method must be copied from

     * the ClassReader associated to this writer in <code>cw.cr</code>. More

     * precisely, this field gives the number of bytes to copied from

     * <code>cw.cr.b</code>.

     */

    int classReaderLength;

    /**

     * Number of exceptions that can be thrown by this method.

     */

    int exceptionCount;

    /**

     * The exceptions that can be thrown by this method. More precisely, this

     * array contains the indexes of the constant pool items that contain the

     * internal names of these exception classes.

     */

    int[] exceptions;

    /**

     * The annotation default attribute of this method. May be <tt>null</tt>.

     */

    private ByteVector annd;

    /**

     * The runtime visible annotations of this method. May be <tt>null</tt>.

     */

    private AnnotationWriter anns;

    /**

     * The runtime invisible annotations of this method. May be <tt>null</tt>.

     */

    private AnnotationWriter ianns;

    /**

     * The runtime visible parameter annotations of this method. May be

     * <tt>null</tt>.

     */

    private AnnotationWriter[] panns;

    /**

     * The runtime invisible parameter annotations of this method. May be

     * <tt>null</tt>.

     */

    private AnnotationWriter[] ipanns;

    /**

     * The number of synthetic parameters of this method.

     */

    private int synthetics;

    /**

     * The non standard attributes of the method.

     */

    private Attribute attrs;

    /**

     * The bytecode of this method.

     */

    private ByteVector code = new ByteVector();

    /**

     * Maximum stack size of this method.

     */

    private int maxStack;

    /**

     * Maximum number of local variables for this method.

     */

    private int maxLocals;

    /**

     * Number of stack map frames in the StackMapTable attribute.

     */

    private int frameCount;

    /**

     * The StackMapTable attribute.

     */

    private ByteVector stackMap;

    /**

     * The offset of the last frame that was written in the StackMapTable

     * attribute.

     */

    private int previousFrameOffset;

    /**

     * The last frame that was written in the StackMapTable attribute.

     *

     * @see #frame

     */

    private int[] previousFrame;

    /**

     * Index of the next element to be added in {@link #frame}.

     */

    private int frameIndex;

    /**

     * The current stack map frame. The first element contains the offset of the

     * instruction to which the frame corresponds, the second element is the

     * number of locals and the third one is the number of stack elements. The

     * local variables start at index 3 and are followed by the operand stack

     * values. In summary frame[0] = offset, frame[1] = nLocal, frame[2] =

     * nStack, frame[3] = nLocal. All types are encoded as integers, with the

     * same format as the one used in {@link Label}, but limited to BASE types.

     */

    private int[] frame;

    /**

     * Number of elements in the exception handler list.

     */

    private int handlerCount;

    /**

     * The first element in the exception handler list.

     */

    private Handler firstHandler;

    /**

     * The last element in the exception handler list.

     */

    private Handler lastHandler;

    /**

     * Number of entries in the LocalVariableTable attribute.

     */

    private int localVarCount;

    /**

     * The LocalVariableTable attribute.

     */

    private ByteVector localVar;

    /**

     * Number of entries in the LocalVariableTypeTable attribute.

     */

    private int localVarTypeCount;

    /**

     * The LocalVariableTypeTable attribute.

     */

    private ByteVector localVarType;

    /**

     * Number of entries in the LineNumberTable attribute.

     */

    private int lineNumberCount;

    /**

     * The LineNumberTable attribute.

     */

    private ByteVector lineNumber;

    /**

     * The non standard attributes of the method's code.

     */

    private Attribute cattrs;

    /**

     * Indicates if some jump instructions are too small and need to be resized.

     */

    private boolean resize;

    /**

     * The number of subroutines in this method.

     */

    private int subroutines;

    // ------------------------------------------------------------------------

    /*

     * Fields for the control flow graph analysis algorithm (used to compute the

     * maximum stack size). A control flow graph contains one node per "basic

     * block", and one edge per "jump" from one basic block to another. Each

     * node (i.e., each basic block) is represented by the Label object that

     * corresponds to the first instruction of this basic block. Each node also

     * stores the list of its successors in the graph, as a linked list of Edge

     * objects.

     */

    /**

     * Indicates what must be automatically computed.

     *

     * @see #FRAMES

     * @see #MAXS

     * @see #NOTHING

     */

    private final int compute;

    /**

     * A list of labels. This list is the list of basic blocks in the method,

     * i.e. a list of Label objects linked to each other by their

     * {@link Label#successor} field, in the order they are visited by

     * {@link MethodVisitor#visitLabel}, and starting with the first basic block.

     */

    private Label labels;

    /**

     * The previous basic block.

     */

    private Label previousBlock;

    /**

     * The current basic block.

     */

    private Label currentBlock;

    /**

     * The (relative) stack size after the last visited instruction. This size

     * is relative to the beginning of the current basic block, i.e., the true

     * stack size after the last visited instruction is equal to the

     * {@link Label#inputStackTop beginStackSize} of the current basic block

     * plus <tt>stackSize</tt>.

     */

    private int stackSize;

    /**

     * The (relative) maximum stack size after the last visited instruction.

     * This size is relative to the beginning of the current basic block, i.e.,

     * the true maximum stack size after the last visited instruction is equal

     * to the {@link Label#inputStackTop beginStackSize} of the current basic

     * block plus <tt>stackSize</tt>.

     */

    private int maxStackSize;

    // ------------------------------------------------------------------------

    // Constructor

    // ------------------------------------------------------------------------

    /**

     * Constructs a new {@link MethodWriter}.

     *

     * @param cw the class writer in which the method must be added.

     * @param access the method's access flags (see {@link Opcodes}).

     * @param name the method's name.

     * @param desc the method's descriptor (see {@link Type}).

     * @param signature the method's signature. May be <tt>null</tt>.

     * @param exceptions the internal names of the method's exceptions. May be

     *        <tt>null</tt>.

     * @param computeMaxs <tt>true</tt> if the maximum stack size and number

     *        of local variables must be automatically computed.

     * @param computeFrames <tt>true</tt> if the stack map tables must be

     *        recomputed from scratch.

     */

    MethodWriter(

        final ClassWriter cw,

        final int access,

        final String name,

        final String desc,

        final String signature,

        final String[] exceptions,

        final boolean computeMaxs,

        final boolean computeFrames)

    {

        if (cw.firstMethod == null) {

            cw.firstMethod = this;

        } else {

            cw.lastMethod.next = this;

        }

        cw.lastMethod = this;

        this.cw = cw;

        this.access = access;

        this.name = cw.newUTF8(name);

        this.desc = cw.newUTF8(desc);

        this.descriptor = desc;

        if (ClassReader.SIGNATURES) {

            this.signature = signature;

        }

        if (exceptions != null && exceptions.length > 0) {

            exceptionCount = exceptions.length;

            this.exceptions = new int[exceptionCount];

            for (int i = 0; i < exceptionCount; ++i) {

                this.exceptions[i] = cw.newClass(exceptions[i]);

            }

        }

        this.compute = computeFrames ? FRAMES : (computeMaxs ? MAXS : NOTHING);

        if (computeMaxs || computeFrames) {

            if (computeFrames && "<init>".equals(name)) {

                this.access |= ACC_CONSTRUCTOR;

            }

            // updates maxLocals

            int size = getArgumentsAndReturnSizes(descriptor) >> 2;

            if ((access & Opcodes.ACC_STATIC) != 0) {

                --size;

            }

            maxLocals = size;

            // creates and visits the label for the first basic block

            labels = new Label();

            labels.status |= Label.PUSHED;

            visitLabel(labels);

        }

    }

    // ------------------------------------------------------------------------

    // Implementation of the MethodVisitor interface

    // ------------------------------------------------------------------------

    public AnnotationVisitor visitAnnotationDefault() {

        if (!ClassReader.ANNOTATIONS) {

            return null;

        }

        annd = new ByteVector();

        return new AnnotationWriter(cw, false, annd, null, 0);

    }

    public AnnotationVisitor visitAnnotation(

        final String desc,

        final boolean visible)

    {

        if (!ClassReader.ANNOTATIONS) {

            return null;

        }

        ByteVector bv = new ByteVector();

        // write type, and reserve space for values count

        bv.putShort(cw.newUTF8(desc)).putShort(0);

        AnnotationWriter aw = new AnnotationWriter(cw, true, bv, bv, 2);

        if (visible) {

            aw.next = anns;

            anns = aw;

        } else {

            aw.next = ianns;

            ianns = aw;

        }

        return aw;

    }

    public AnnotationVisitor visitParameterAnnotation(

        final int parameter,

        final String desc,

        final boolean visible)

    {

        if (!ClassReader.ANNOTATIONS) {

            return null;