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From hyun...@apache.org
Subject [16/25] TAJO-906: Runtime code generation for evaluating expression trees.
Date Sat, 23 Aug 2014 17:38:05 GMT
http://git-wip-us.apache.org/repos/asf/tajo/blob/7603a3d4/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodWriter.java
----------------------------------------------------------------------
diff --git a/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodWriter.java b/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodWriter.java
new file mode 100644
index 0000000..290cf97
--- /dev/null
+++ b/tajo-thirdparty/asm/src/main/java/org/apache/tajo/org/objectweb/asm/MethodWriter.java
@@ -0,0 +1,2685 @@
+/***
+ * 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 org.apache.tajo.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 extends MethodVisitor {
+
+    /**
+     * Pseudo access flag used to denote constructors.
+     */
+    static final int ACC_CONSTRUCTOR = 0x80000;
+    
+    /**
+     * 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;
+
+    /**
+     * 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 local variables in the current stack map frame.
+     */
+    private int currentLocals;
+
+    /**
+     * 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;
+
+    /**
+     * 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) {
+        super(Opcodes.ASM4);
+        if (cw.firstMethod == null) {
+            cw.firstMethod = this;
+        } else {
+            cw.lastMethod.mv = this;
+        }
+        cw.lastMethod = this;
+        this.cw = cw;
+        this.access = access;
+        if ("<init>".equals(name)) {
+            this.access |= ACC_CONSTRUCTOR;
+        }
+        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) {
+            // updates maxLocals
+            int size = Type.getArgumentsAndReturnSizes(descriptor) >> 2;
+            if ((access & Opcodes.ACC_STATIC) != 0) {
+                --size;
+            }
+            maxLocals = size;
+            currentLocals = size;
+            // creates and visits the label for the first basic block
+            labels = new Label();
+            labels.status |= Label.PUSHED;
+            visitLabel(labels);
+        }
+    }
+
+    // ------------------------------------------------------------------------
+    // Implementation of the MethodVisitor abstract class
+    // ------------------------------------------------------------------------
+
+    @Override
+    public AnnotationVisitor visitAnnotationDefault() {
+        if (!ClassReader.ANNOTATIONS) {
+            return null;
+        }
+        annd = new ByteVector();
+        return new AnnotationWriter(cw, false, annd, null, 0);
+    }
+
+    @Override
+    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;
+    }
+
+    @Override
+    public AnnotationVisitor visitParameterAnnotation(final int parameter,
+            final String desc, final boolean visible) {
+        if (!ClassReader.ANNOTATIONS) {
+            return null;
+        }
+        ByteVector bv = new ByteVector();
+        if ("Ljava/lang/Synthetic;".equals(desc)) {
+            // workaround for a bug in javac with synthetic parameters
+            // see ClassReader.readParameterAnnotations
+            synthetics = Math.max(synthetics, parameter + 1);
+            return new AnnotationWriter(cw, false, bv, null, 0);
+        }
+        // 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) {
+            if (panns == null) {
+                panns = new AnnotationWriter[Type.getArgumentTypes(descriptor).length];
+            }
+            aw.next = panns[parameter];
+            panns[parameter] = aw;
+        } else {
+            if (ipanns == null) {
+                ipanns = new AnnotationWriter[Type.getArgumentTypes(descriptor).length];
+            }
+            aw.next = ipanns[parameter];
+            ipanns[parameter] = aw;
+        }
+        return aw;
+    }
+
+    @Override
+    public void visitAttribute(final Attribute attr) {
+        if (attr.isCodeAttribute()) {
+            attr.next = cattrs;
+            cattrs = attr;
+        } else {
+            attr.next = attrs;
+            attrs = attr;
+        }
+    }
+
+    @Override
+    public void visitCode() {
+    }
+
+    @Override
+    public void visitFrame(final int type, final int nLocal,
+            final Object[] local, final int nStack, final Object[] stack) {
+        if (!ClassReader.FRAMES || compute == FRAMES) {
+            return;
+        }
+
+        if (type == Opcodes.F_NEW) {
+            if (previousFrame == null) {
+                visitImplicitFirstFrame();
+            }
+            currentLocals = nLocal;
+            int frameIndex = startFrame(code.length, nLocal, nStack);
+            for (int i = 0; i < nLocal; ++i) {
+                if (local[i] instanceof String) {
+                    frame[frameIndex++] = Frame.OBJECT
+                            | cw.addType((String) local[i]);
+                } else if (local[i] instanceof Integer) {
+                    frame[frameIndex++] = ((Integer) local[i]).intValue();
+                } else {
+                    frame[frameIndex++] = Frame.UNINITIALIZED
+                            | cw.addUninitializedType("",
+                                    ((Label) local[i]).position);
+                }
+            }
+            for (int i = 0; i < nStack; ++i) {
+                if (stack[i] instanceof String) {
+                    frame[frameIndex++] = Frame.OBJECT
+                            | cw.addType((String) stack[i]);
+                } else if (stack[i] instanceof Integer) {
+                    frame[frameIndex++] = ((Integer) stack[i]).intValue();
+                } else {
+                    frame[frameIndex++] = Frame.UNINITIALIZED
+                            | cw.addUninitializedType("",
+                                    ((Label) stack[i]).position);
+                }
+            }
+            endFrame();
+        } else {
+            int delta;
+            if (stackMap == null) {
+                stackMap = new ByteVector();
+                delta = code.length;
+            } else {
+                delta = code.length - previousFrameOffset - 1;
+                if (delta < 0) {
+                    if (type == Opcodes.F_SAME) {
+                        return;
+                    } else {
+                        throw new IllegalStateException();
+                    }
+                }
+            }
+
+            switch (type) {
+            case Opcodes.F_FULL:
+                currentLocals = nLocal;
+                stackMap.putByte(FULL_FRAME).putShort(delta).putShort(nLocal);
+                for (int i = 0; i < nLocal; ++i) {
+                    writeFrameType(local[i]);
+                }
+                stackMap.putShort(nStack);
+                for (int i = 0; i < nStack; ++i) {
+                    writeFrameType(stack[i]);
+                }
+                break;
+            case Opcodes.F_APPEND:
+                currentLocals += nLocal;
+                stackMap.putByte(SAME_FRAME_EXTENDED + nLocal).putShort(delta);
+                for (int i = 0; i < nLocal; ++i) {
+                    writeFrameType(local[i]);
+                }
+                break;
+            case Opcodes.F_CHOP:
+                currentLocals -= nLocal;
+                stackMap.putByte(SAME_FRAME_EXTENDED - nLocal).putShort(delta);
+                break;
+            case Opcodes.F_SAME:
+                if (delta < 64) {
+                    stackMap.putByte(delta);
+                } else {
+                    stackMap.putByte(SAME_FRAME_EXTENDED).putShort(delta);
+                }
+                break;
+            case Opcodes.F_SAME1:
+                if (delta < 64) {
+                    stackMap.putByte(SAME_LOCALS_1_STACK_ITEM_FRAME + delta);
+                } else {
+                    stackMap.putByte(SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED)
+                            .putShort(delta);
+                }
+                writeFrameType(stack[0]);
+                break;
+            }
+
+            previousFrameOffset = code.length;
+            ++frameCount;
+        }
+
+        maxStack = Math.max(maxStack, nStack);
+        maxLocals = Math.max(maxLocals, currentLocals);
+    }
+
+    @Override
+    public void visitInsn(final int opcode) {
+        // adds the instruction to the bytecode of the method
+        code.putByte(opcode);
+        // update currentBlock
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(opcode, 0, null, null);
+            } else {
+                // updates current and max stack sizes
+                int size = stackSize + Frame.SIZE[opcode];
+                if (size > maxStackSize) {
+                    maxStackSize = size;
+                }
+                stackSize = size;
+            }
+            // if opcode == ATHROW or xRETURN, ends current block (no successor)
+            if ((opcode >= Opcodes.IRETURN && opcode <= Opcodes.RETURN)
+                    || opcode == Opcodes.ATHROW) {
+                noSuccessor();
+            }
+        }
+    }
+
+    @Override
+    public void visitIntInsn(final int opcode, final int operand) {
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(opcode, operand, null, null);
+            } else if (opcode != Opcodes.NEWARRAY) {
+                // updates current and max stack sizes only for NEWARRAY
+                // (stack size variation = 0 for BIPUSH or SIPUSH)
+                int size = stackSize + 1;
+                if (size > maxStackSize) {
+                    maxStackSize = size;
+                }
+                stackSize = size;
+            }
+        }
+        // adds the instruction to the bytecode of the method
+        if (opcode == Opcodes.SIPUSH) {
+            code.put12(opcode, operand);
+        } else { // BIPUSH or NEWARRAY
+            code.put11(opcode, operand);
+        }
+    }
+
+    @Override
+    public void visitVarInsn(final int opcode, final int var) {
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(opcode, var, null, null);
+            } else {
+                // updates current and max stack sizes
+                if (opcode == Opcodes.RET) {
+                    // no stack change, but end of current block (no successor)
+                    currentBlock.status |= Label.RET;
+                    // save 'stackSize' here for future use
+                    // (see {@link #findSubroutineSuccessors})
+                    currentBlock.inputStackTop = stackSize;
+                    noSuccessor();
+                } else { // xLOAD or xSTORE
+                    int size = stackSize + Frame.SIZE[opcode];
+                    if (size > maxStackSize) {
+                        maxStackSize = size;
+                    }
+                    stackSize = size;
+                }
+            }
+        }
+        if (compute != NOTHING) {
+            // updates max locals
+            int n;
+            if (opcode == Opcodes.LLOAD || opcode == Opcodes.DLOAD
+                    || opcode == Opcodes.LSTORE || opcode == Opcodes.DSTORE) {
+                n = var + 2;
+            } else {
+                n = var + 1;
+            }
+            if (n > maxLocals) {
+                maxLocals = n;
+            }
+        }
+        // adds the instruction to the bytecode of the method
+        if (var < 4 && opcode != Opcodes.RET) {
+            int opt;
+            if (opcode < Opcodes.ISTORE) {
+                /* ILOAD_0 */
+                opt = 26 + ((opcode - Opcodes.ILOAD) << 2) + var;
+            } else {
+                /* ISTORE_0 */
+                opt = 59 + ((opcode - Opcodes.ISTORE) << 2) + var;
+            }
+            code.putByte(opt);
+        } else if (var >= 256) {
+            code.putByte(196 /* WIDE */).put12(opcode, var);
+        } else {
+            code.put11(opcode, var);
+        }
+        if (opcode >= Opcodes.ISTORE && compute == FRAMES && handlerCount > 0) {
+            visitLabel(new Label());
+        }
+    }
+
+    @Override
+    public void visitTypeInsn(final int opcode, final String type) {
+        Item i = cw.newClassItem(type);
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(opcode, code.length, cw, i);
+            } else if (opcode == Opcodes.NEW) {
+                // updates current and max stack sizes only if opcode == NEW
+                // (no stack change for ANEWARRAY, CHECKCAST, INSTANCEOF)
+                int size = stackSize + 1;
+                if (size > maxStackSize) {
+                    maxStackSize = size;
+                }
+                stackSize = size;
+            }
+        }
+        // adds the instruction to the bytecode of the method
+        code.put12(opcode, i.index);
+    }
+
+    @Override
+    public void visitFieldInsn(final int opcode, final String owner,
+            final String name, final String desc) {
+        Item i = cw.newFieldItem(owner, name, desc);
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(opcode, 0, cw, i);
+            } else {
+                int size;
+                // computes the stack size variation
+                char c = desc.charAt(0);
+                switch (opcode) {
+                case Opcodes.GETSTATIC:
+                    size = stackSize + (c == 'D' || c == 'J' ? 2 : 1);
+                    break;
+                case Opcodes.PUTSTATIC:
+                    size = stackSize + (c == 'D' || c == 'J' ? -2 : -1);
+                    break;
+                case Opcodes.GETFIELD:
+                    size = stackSize + (c == 'D' || c == 'J' ? 1 : 0);
+                    break;
+                // case Constants.PUTFIELD:
+                default:
+                    size = stackSize + (c == 'D' || c == 'J' ? -3 : -2);
+                    break;
+                }
+                // updates current and max stack sizes
+                if (size > maxStackSize) {
+                    maxStackSize = size;
+                }
+                stackSize = size;
+            }
+        }
+        // adds the instruction to the bytecode of the method
+        code.put12(opcode, i.index);
+    }
+
+    @Override
+    public void visitMethodInsn(final int opcode, final String owner,
+            final String name, final String desc) {
+        boolean itf = opcode == Opcodes.INVOKEINTERFACE;
+        Item i = cw.newMethodItem(owner, name, desc, itf);
+        int argSize = i.intVal;
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(opcode, 0, cw, i);
+            } else {
+                /*
+                 * computes the stack size variation. In order not to recompute
+                 * several times this variation for the same Item, we use the
+                 * intVal field of this item to store this variation, once it
+                 * has been computed. More precisely this intVal field stores
+                 * the sizes of the arguments and of the return value
+                 * corresponding to desc.
+                 */
+                if (argSize == 0) {
+                    // the above sizes have not been computed yet,
+                    // so we compute them...
+                    argSize = Type.getArgumentsAndReturnSizes(desc);
+                    // ... and we save them in order
+                    // not to recompute them in the future
+                    i.intVal = argSize;
+                }
+                int size;
+                if (opcode == Opcodes.INVOKESTATIC) {
+                    size = stackSize - (argSize >> 2) + (argSize & 0x03) + 1;
+                } else {
+                    size = stackSize - (argSize >> 2) + (argSize & 0x03);
+                }
+                // updates current and max stack sizes
+                if (size > maxStackSize) {
+                    maxStackSize = size;
+                }
+                stackSize = size;
+            }
+        }
+        // adds the instruction to the bytecode of the method
+        if (itf) {
+            if (argSize == 0) {
+                argSize = Type.getArgumentsAndReturnSizes(desc);
+                i.intVal = argSize;
+            }
+            code.put12(Opcodes.INVOKEINTERFACE, i.index).put11(argSize >> 2, 0);
+        } else {
+            code.put12(opcode, i.index);
+        }
+    }
+
+    @Override
+    public void visitInvokeDynamicInsn(final String name, final String desc,
+            final Handle bsm, final Object... bsmArgs) {
+        Item i = cw.newInvokeDynamicItem(name, desc, bsm, bsmArgs);
+        int argSize = i.intVal;
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(Opcodes.INVOKEDYNAMIC, 0, cw, i);
+            } else {
+                /*
+                 * computes the stack size variation. In order not to recompute
+                 * several times this variation for the same Item, we use the
+                 * intVal field of this item to store this variation, once it
+                 * has been computed. More precisely this intVal field stores
+                 * the sizes of the arguments and of the return value
+                 * corresponding to desc.
+                 */
+                if (argSize == 0) {
+                    // the above sizes have not been computed yet,
+                    // so we compute them...
+                    argSize = Type.getArgumentsAndReturnSizes(desc);
+                    // ... and we save them in order
+                    // not to recompute them in the future
+                    i.intVal = argSize;
+                }
+                int size = stackSize - (argSize >> 2) + (argSize & 0x03) + 1;
+
+                // updates current and max stack sizes
+                if (size > maxStackSize) {
+                    maxStackSize = size;
+                }
+                stackSize = size;
+            }
+        }
+        // adds the instruction to the bytecode of the method
+        code.put12(Opcodes.INVOKEDYNAMIC, i.index);
+        code.putShort(0);
+    }
+
+    @Override
+    public void visitJumpInsn(final int opcode, final Label label) {
+        Label nextInsn = null;
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(opcode, 0, null, null);
+                // 'label' is the target of a jump instruction
+                label.getFirst().status |= Label.TARGET;
+                // adds 'label' as a successor of this basic block
+                addSuccessor(Edge.NORMAL, label);
+                if (opcode != Opcodes.GOTO) {
+                    // creates a Label for the next basic block
+                    nextInsn = new Label();
+                }
+            } else {
+                if (opcode == Opcodes.JSR) {
+                    if ((label.status & Label.SUBROUTINE) == 0) {
+                        label.status |= Label.SUBROUTINE;
+                        ++subroutines;
+                    }
+                    currentBlock.status |= Label.JSR;
+                    addSuccessor(stackSize + 1, label);
+                    // creates a Label for the next basic block
+                    nextInsn = new Label();
+                    /*
+                     * note that, by construction in this method, a JSR block
+                     * has at least two successors in the control flow graph:
+                     * the first one leads the next instruction after the JSR,
+                     * while the second one leads to the JSR target.
+                     */
+                } else {
+                    // updates current stack size (max stack size unchanged
+                    // because stack size variation always negative in this
+                    // case)
+                    stackSize += Frame.SIZE[opcode];
+                    addSuccessor(stackSize, label);
+                }
+            }
+        }
+        // adds the instruction to the bytecode of the method
+        if ((label.status & Label.RESOLVED) != 0
+                && label.position - code.length < Short.MIN_VALUE) {
+            /*
+             * case of a backward jump with an offset < -32768. In this case we
+             * automatically replace GOTO with GOTO_W, JSR with JSR_W and IFxxx
+             * <l> with IFNOTxxx <l'> GOTO_W <l>, where IFNOTxxx is the
+             * "opposite" opcode of IFxxx (i.e., IFNE for IFEQ) and where <l'>
+             * designates the instruction just after the GOTO_W.
+             */
+            if (opcode == Opcodes.GOTO) {
+                code.putByte(200); // GOTO_W
+            } else if (opcode == Opcodes.JSR) {
+                code.putByte(201); // JSR_W
+            } else {
+                // if the IF instruction is transformed into IFNOT GOTO_W the
+                // next instruction becomes the target of the IFNOT instruction
+                if (nextInsn != null) {
+                    nextInsn.status |= Label.TARGET;
+                }
+                code.putByte(opcode <= 166 ? ((opcode + 1) ^ 1) - 1
+                        : opcode ^ 1);
+                code.putShort(8); // jump offset
+                code.putByte(200); // GOTO_W
+            }
+            label.put(this, code, code.length - 1, true);
+        } else {
+            /*
+             * case of a backward jump with an offset >= -32768, or of a forward
+             * jump with, of course, an unknown offset. In these cases we store
+             * the offset in 2 bytes (which will be increased in
+             * resizeInstructions, if needed).
+             */
+            code.putByte(opcode);
+            label.put(this, code, code.length - 1, false);
+        }
+        if (currentBlock != null) {
+            if (nextInsn != null) {
+                // if the jump instruction is not a GOTO, the next instruction
+                // is also a successor of this instruction. Calling visitLabel
+                // adds the label of this next instruction as a successor of the
+                // current block, and starts a new basic block
+                visitLabel(nextInsn);
+            }
+            if (opcode == Opcodes.GOTO) {
+                noSuccessor();
+            }
+        }
+    }
+
+    @Override
+    public void visitLabel(final Label label) {
+        // resolves previous forward references to label, if any
+        resize |= label.resolve(this, code.length, code.data);
+        // updates currentBlock
+        if ((label.status & Label.DEBUG) != 0) {
+            return;
+        }
+        if (compute == FRAMES) {
+            if (currentBlock != null) {
+                if (label.position == currentBlock.position) {
+                    // successive labels, do not start a new basic block
+                    currentBlock.status |= (label.status & Label.TARGET);
+                    label.frame = currentBlock.frame;
+                    return;
+                }
+                // ends current block (with one new successor)
+                addSuccessor(Edge.NORMAL, label);
+            }
+            // begins a new current block
+            currentBlock = label;
+            if (label.frame == null) {
+                label.frame = new Frame();
+                label.frame.owner = label;
+            }
+            // updates the basic block list
+            if (previousBlock != null) {
+                if (label.position == previousBlock.position) {
+                    previousBlock.status |= (label.status & Label.TARGET);
+                    label.frame = previousBlock.frame;
+                    currentBlock = previousBlock;
+                    return;
+                }
+                previousBlock.successor = label;
+            }
+            previousBlock = label;
+        } else if (compute == MAXS) {
+            if (currentBlock != null) {
+                // ends current block (with one new successor)
+                currentBlock.outputStackMax = maxStackSize;
+                addSuccessor(stackSize, label);
+            }
+            // begins a new current block
+            currentBlock = label;
+            // resets the relative current and max stack sizes
+            stackSize = 0;
+            maxStackSize = 0;
+            // updates the basic block list
+            if (previousBlock != null) {
+                previousBlock.successor = label;
+            }
+            previousBlock = label;
+        }
+    }
+
+    @Override
+    public void visitLdcInsn(final Object cst) {
+        Item i = cw.newConstItem(cst);
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(Opcodes.LDC, 0, cw, i);
+            } else {
+                int size;
+                // computes the stack size variation
+                if (i.type == ClassWriter.LONG || i.type == ClassWriter.DOUBLE) {
+                    size = stackSize + 2;
+                } else {
+                    size = stackSize + 1;
+                }
+                // updates current and max stack sizes
+                if (size > maxStackSize) {
+                    maxStackSize = size;
+                }
+                stackSize = size;
+            }
+        }
+        // adds the instruction to the bytecode of the method
+        int index = i.index;
+        if (i.type == ClassWriter.LONG || i.type == ClassWriter.DOUBLE) {
+            code.put12(20 /* LDC2_W */, index);
+        } else if (index >= 256) {
+            code.put12(19 /* LDC_W */, index);
+        } else {
+            code.put11(Opcodes.LDC, index);
+        }
+    }
+
+    @Override
+    public void visitIincInsn(final int var, final int increment) {
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(Opcodes.IINC, var, null, null);
+            }
+        }
+        if (compute != NOTHING) {
+            // updates max locals
+            int n = var + 1;
+            if (n > maxLocals) {
+                maxLocals = n;
+            }
+        }
+        // adds the instruction to the bytecode of the method
+        if ((var > 255) || (increment > 127) || (increment < -128)) {
+            code.putByte(196 /* WIDE */).put12(Opcodes.IINC, var)
+                    .putShort(increment);
+        } else {
+            code.putByte(Opcodes.IINC).put11(var, increment);
+        }
+    }
+
+    @Override
+    public void visitTableSwitchInsn(final int min, final int max,
+            final Label dflt, final Label... labels) {
+        // adds the instruction to the bytecode of the method
+        int source = code.length;
+        code.putByte(Opcodes.TABLESWITCH);
+        code.putByteArray(null, 0, (4 - code.length % 4) % 4);
+        dflt.put(this, code, source, true);
+        code.putInt(min).putInt(max);
+        for (int i = 0; i < labels.length; ++i) {
+            labels[i].put(this, code, source, true);
+        }
+        // updates currentBlock
+        visitSwitchInsn(dflt, labels);
+    }
+
+    @Override
+    public void visitLookupSwitchInsn(final Label dflt, final int[] keys,
+            final Label[] labels) {
+        // adds the instruction to the bytecode of the method
+        int source = code.length;
+        code.putByte(Opcodes.LOOKUPSWITCH);
+        code.putByteArray(null, 0, (4 - code.length % 4) % 4);
+        dflt.put(this, code, source, true);
+        code.putInt(labels.length);
+        for (int i = 0; i < labels.length; ++i) {
+            code.putInt(keys[i]);
+            labels[i].put(this, code, source, true);
+        }
+        // updates currentBlock
+        visitSwitchInsn(dflt, labels);
+    }
+
+    private void visitSwitchInsn(final Label dflt, final Label[] labels) {
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(Opcodes.LOOKUPSWITCH, 0, null, null);
+                // adds current block successors
+                addSuccessor(Edge.NORMAL, dflt);
+                dflt.getFirst().status |= Label.TARGET;
+                for (int i = 0; i < labels.length; ++i) {
+                    addSuccessor(Edge.NORMAL, labels[i]);
+                    labels[i].getFirst().status |= Label.TARGET;
+                }
+            } else {
+                // updates current stack size (max stack size unchanged)
+                --stackSize;
+                // adds current block successors
+                addSuccessor(stackSize, dflt);
+                for (int i = 0; i < labels.length; ++i) {
+                    addSuccessor(stackSize, labels[i]);
+                }
+            }
+            // ends current block
+            noSuccessor();
+        }
+    }
+
+    @Override
+    public void visitMultiANewArrayInsn(final String desc, final int dims) {
+        Item i = cw.newClassItem(desc);
+        // Label currentBlock = this.currentBlock;
+        if (currentBlock != null) {
+            if (compute == FRAMES) {
+                currentBlock.frame.execute(Opcodes.MULTIANEWARRAY, dims, cw, i);
+            } else {
+                // updates current stack size (max stack size unchanged because
+                // stack size variation always negative or null)
+                stackSize += 1 - dims;
+            }
+        }
+        // adds the instruction to the bytecode of the method
+        code.put12(Opcodes.MULTIANEWARRAY, i.index).putByte(dims);
+    }
+
+    @Override
+    public void visitTryCatchBlock(final Label start, final Label end,
+            final Label handler, final String type) {
+        ++handlerCount;
+        Handler h = new Handler();
+        h.start = start;
+        h.end = end;
+        h.handler = handler;
+        h.desc = type;
+        h.type = type != null ? cw.newClass(type) : 0;
+        if (lastHandler == null) {
+            firstHandler = h;
+        } else {
+            lastHandler.next = h;
+        }
+        lastHandler = h;
+    }
+
+    @Override
+    public void visitLocalVariable(final String name, final String desc,
+            final String signature, final Label start, final Label end,
+            final int index) {
+        if (signature != null) {
+            if (localVarType == null) {
+                localVarType = new ByteVector();
+            }
+            ++localVarTypeCount;
+            localVarType.putShort(start.position)
+                    .putShort(end.position - start.position)
+                    .putShort(cw.newUTF8(name)).putShort(cw.newUTF8(signature))
+                    .putShort(index);
+        }
+        if (localVar == null) {
+            localVar = new ByteVector();
+        }
+        ++localVarCount;
+        localVar.putShort(start.position)
+                .putShort(end.position - start.position)
+                .putShort(cw.newUTF8(name)).putShort(cw.newUTF8(desc))
+                .putShort(index);
+        if (compute != NOTHING) {
+            // updates max locals
+            char c = desc.charAt(0);
+            int n = index + (c == 'J' || c == 'D' ? 2 : 1);
+            if (n > maxLocals) {
+                maxLocals = n;
+            }
+        }
+    }
+
+    @Override
+    public void visitLineNumber(final int line, final Label start) {
+        if (lineNumber == null) {
+            lineNumber = new ByteVector();
+        }
+        ++lineNumberCount;
+        lineNumber.putShort(start.position);
+        lineNumber.putShort(line);
+    }
+
+    @Override
+    public void visitMaxs(final int maxStack, final int maxLocals) {
+        if (ClassReader.FRAMES && compute == FRAMES) {
+            // completes the control flow graph with exception handler blocks
+            Handler handler = firstHandler;
+            while (handler != null) {
+                Label l = handler.start.getFirst();
+                Label h = handler.handler.getFirst();
+                Label e = handler.end.getFirst();
+                // computes the kind of the edges to 'h'
+                String t = handler.desc == null ? "java/lang/Throwable"
+                        : handler.desc;
+                int kind = Frame.OBJECT | cw.addType(t);
+                // h is an exception handler
+                h.status |= Label.TARGET;
+                // adds 'h' as a successor of labels between 'start' and 'end'
+                while (l != e) {
+                    // creates an edge to 'h'
+                    Edge b = new Edge();
+                    b.info = kind;
+                    b.successor = h;
+                    // adds it to the successors of 'l'
+                    b.next = l.successors;
+                    l.successors = b;
+                    // goes to the next label
+                    l = l.successor;
+                }
+                handler = handler.next;
+            }
+
+            // creates and visits the first (implicit) frame
+            Frame f = labels.frame;
+            Type[] args = Type.getArgumentTypes(descriptor);
+            f.initInputFrame(cw, access, args, this.maxLocals);
+            visitFrame(f);
+
+            /*
+             * fix point algorithm: mark the first basic block as 'changed'
+             * (i.e. put it in the 'changed' list) and, while there are changed
+             * basic blocks, choose one, mark it as unchanged, and update its
+             * successors (which can be changed in the process).
+             */
+            int max = 0;
+            Label changed = labels;
+            while (changed != null) {
+                // removes a basic block from the list of changed basic blocks
+                Label l = changed;
+                changed = changed.next;
+                l.next = null;
+                f = l.frame;
+                // a reachable jump target must be stored in the stack map
+                if ((l.status & Label.TARGET) != 0) {
+                    l.status |= Label.STORE;
+                }
+                // all visited labels are reachable, by definition
+                l.status |= Label.REACHABLE;
+                // updates the (absolute) maximum stack size
+                int blockMax = f.inputStack.length + l.outputStackMax;
+                if (blockMax > max) {
+                    max = blockMax;
+                }
+                // updates the successors of the current basic block
+                Edge e = l.successors;
+                while (e != null) {
+                    Label n = e.successor.getFirst();
+                    boolean change = f.merge(cw, n.frame, e.info);
+                    if (change && n.next == null) {
+                        // if n has changed and is not already in the 'changed'
+                        // list, adds it to this list
+                        n.next = changed;
+                        changed = n;
+                    }
+                    e = e.next;
+                }
+            }
+
+            // visits all the frames that must be stored in the stack map
+            Label l = labels;
+            while (l != null) {
+                f = l.frame;
+                if ((l.status & Label.STORE) != 0) {
+                    visitFrame(f);
+                }
+                if ((l.status & Label.REACHABLE) == 0) {
+                    // finds start and end of dead basic block
+                    Label k = l.successor;
+                    int start = l.position;
+                    int end = (k == null ? code.length : k.position) - 1;
+                    // if non empty basic block
+                    if (end >= start) {
+                        max = Math.max(max, 1);
+                        // replaces instructions with NOP ... NOP ATHROW
+                        for (int i = start; i < end; ++i) {
+                            code.data[i] = Opcodes.NOP;
+                        }
+                        code.data[end] = (byte) Opcodes.ATHROW;
+                        // emits a frame for this unreachable block
+                        int frameIndex = startFrame(start, 0, 1);
+                        frame[frameIndex] = Frame.OBJECT
+                                | cw.addType("java/lang/Throwable");
+                        endFrame();
+                        // removes the start-end range from the exception
+                        // handlers
+                        firstHandler = Handler.remove(firstHandler, l, k);
+                    }
+                }
+                l = l.successor;
+            }
+
+            handler = firstHandler;
+            handlerCount = 0;
+            while (handler != null) {
+                handlerCount += 1;
+                handler = handler.next;
+            }
+
+            this.maxStack = max;
+        } else if (compute == MAXS) {
+            // completes the control flow graph with exception handler blocks
+            Handler handler = firstHandler;
+            while (handler != null) {
+                Label l = handler.start;
+                Label h = handler.handler;
+                Label e = handler.end;
+                // adds 'h' as a successor of labels between 'start' and 'end'
+                while (l != e) {
+                    // creates an edge to 'h'
+                    Edge b = new Edge();
+                    b.info = Edge.EXCEPTION;
+                    b.successor = h;
+                    // adds it to the successors of 'l'
+                    if ((l.status & Label.JSR) == 0) {
+                        b.next = l.successors;
+                        l.successors = b;
+                    } else {
+                        // if l is a JSR block, adds b after the first two edges
+                        // to preserve the hypothesis about JSR block successors
+                        // order (see {@link #visitJumpInsn})
+                        b.next = l.successors.next.next;
+                        l.successors.next.next = b;
+                    }
+                    // goes to the next label
+                    l = l.successor;
+                }
+                handler = handler.next;
+            }
+
+            if (subroutines > 0) {
+                // completes the control flow graph with the RET successors
+                /*
+                 * first step: finds the subroutines. This step determines, for
+                 * each basic block, to which subroutine(s) it belongs.
+                 */
+                // finds the basic blocks that belong to the "main" subroutine
+                int id = 0;
+                labels.visitSubroutine(null, 1, subroutines);
+                // finds the basic blocks that belong to the real subroutines
+                Label l = labels;
+                while (l != null) {
+                    if ((l.status & Label.JSR) != 0) {
+                        // the subroutine is defined by l's TARGET, not by l
+                        Label subroutine = l.successors.next.successor;
+                        // if this subroutine has not been visited yet...
+                        if ((subroutine.status & Label.VISITED) == 0) {
+                            // ...assigns it a new id and finds its basic blocks
+                            id += 1;
+                            subroutine.visitSubroutine(null, (id / 32L) << 32
+                                    | (1L << (id % 32)), subroutines);
+                        }
+                    }
+                    l = l.successor;
+                }
+                // second step: finds the successors of RET blocks
+                l = labels;
+                while (l != null) {
+                    if ((l.status & Label.JSR) != 0) {
+                        Label L = labels;
+                        while (L != null) {
+                            L.status &= ~Label.VISITED2;
+                            L = L.successor;
+                        }
+                        // the subroutine is defined by l's TARGET, not by l
+                        Label subroutine = l.successors.next.successor;
+                        subroutine.visitSubroutine(l, 0, subroutines);
+                    }
+                    l = l.successor;
+                }
+            }
+
+            /*
+             * control flow analysis algorithm: while the block stack is not
+             * empty, pop a block from this stack, update the max stack size,
+             * compute the true (non relative) begin stack size of the
+             * successors of this block, and push these successors onto the
+             * stack (unless they have already been pushed onto the stack).
+             * Note: by hypothesis, the {@link Label#inputStackTop} of the
+             * blocks in the block stack are the true (non relative) beginning
+             * stack sizes of these blocks.
+             */
+            int max = 0;
+            Label stack = labels;
+            while (stack != null) {
+                // pops a block from the stack
+                Label l = stack;
+                stack = stack.next;
+                // computes the true (non relative) max stack size of this block
+                int start = l.inputStackTop;
+                int blockMax = start + l.outputStackMax;
+                // updates the global max stack size
+                if (blockMax > max) {
+                    max = blockMax;
+                }
+                // analyzes the successors of the block
+                Edge b = l.successors;
+                if ((l.status & Label.JSR) != 0) {
+                    // ignores the first edge of JSR blocks (virtual successor)
+                    b = b.next;
+                }
+                while (b != null) {
+                    l = b.successor;
+                    // if this successor has not already been pushed...
+                    if ((l.status & Label.PUSHED) == 0) {
+                        // computes its true beginning stack size...
+                        l.inputStackTop = b.info == Edge.EXCEPTION ? 1 : start
+                                + b.info;
+                        // ...and pushes it onto the stack
+                        l.status |= Label.PUSHED;
+                        l.next = stack;
+                        stack = l;
+                    }
+                    b = b.next;
+                }
+            }
+            this.maxStack = Math.max(maxStack, max);
+        } else {
+            this.maxStack = maxStack;
+            this.maxLocals = maxLocals;
+        }
+    }
+
+    @Override
+    public void visitEnd() {
+    }
+
+    // ------------------------------------------------------------------------
+    // Utility methods: control flow analysis algorithm
+    // ------------------------------------------------------------------------
+
+    /**
+     * Adds a successor to the {@link #currentBlock currentBlock} block.
+     * 
+     * @param info
+     *            information about the control flow edge to be added.
+     * @param successor
+     *            the successor block to be added to the current block.
+     */
+    private void addSuccessor(final int info, final Label successor) {
+        // creates and initializes an Edge object...
+        Edge b = new Edge();
+        b.info = info;
+        b.successor = successor;
+        // ...and adds it to the successor list of the currentBlock block
+        b.next = currentBlock.successors;
+        currentBlock.successors = b;
+    }
+
+    /**
+     * Ends the current basic block. This method must be used in the case where
+     * the current basic block does not have any successor.
+     */
+    private void noSuccessor() {
+        if (compute == FRAMES) {
+            Label l = new Label();
+            l.frame = new Frame();
+            l.frame.owner = l;
+            l.resolve(this, code.length, code.data);
+            previousBlock.successor = l;
+            previousBlock = l;
+        } else {
+            currentBlock.outputStackMax = maxStackSize;
+        }
+        currentBlock = null;
+    }
+
+    // ------------------------------------------------------------------------
+    // Utility methods: stack map frames
+    // ------------------------------------------------------------------------
+
+    /**
+     * Visits a frame that has been computed from scratch.
+     * 
+     * @param f
+     *            the frame that must be visited.
+     */
+    private void visitFrame(final Frame f) {
+        int i, t;
+        int nTop = 0;
+        int nLocal = 0;
+        int nStack = 0;
+        int[] locals = f.inputLocals;
+        int[] stacks = f.inputStack;
+        // computes the number of locals (ignores TOP types that are just after
+        // a LONG or a DOUBLE, and all trailing TOP types)
+        for (i = 0; i < locals.length; ++i) {
+            t = locals[i];
+            if (t == Frame.TOP) {
+                ++nTop;
+            } else {
+                nLocal += nTop + 1;
+                nTop = 0;
+            }
+            if (t == Frame.LONG || t == Frame.DOUBLE) {
+                ++i;
+            }
+        }
+        // computes the stack size (ignores TOP types that are just after
+        // a LONG or a DOUBLE)
+        for (i = 0; i < stacks.length; ++i) {
+            t = stacks[i];
+            ++nStack;
+            if (t == Frame.LONG || t == Frame.DOUBLE) {
+                ++i;
+            }
+        }
+        // visits the frame and its content
+        int frameIndex = startFrame(f.owner.position, nLocal, nStack);
+        for (i = 0; nLocal > 0; ++i, --nLocal) {
+            t = locals[i];
+            frame[frameIndex++] = t;
+            if (t == Frame.LONG || t == Frame.DOUBLE) {
+                ++i;
+            }
+        }
+        for (i = 0; i < stacks.length; ++i) {
+            t = stacks[i];
+            frame[frameIndex++] = t;
+            if (t == Frame.LONG || t == Frame.DOUBLE) {
+                ++i;
+            }
+        }
+        endFrame();
+    }
+
+    /**
+     * Visit the implicit first frame of this method.
+     */
+    private void visitImplicitFirstFrame() {
+        // There can be at most descriptor.length() + 1 locals
+        int frameIndex = startFrame(0, descriptor.length() + 1, 0);
+        if ((access & Opcodes.ACC_STATIC) == 0) {
+            if ((access & ACC_CONSTRUCTOR) == 0) {
+                frame[frameIndex++] = Frame.OBJECT | cw.addType(cw.thisName);
+            } else {
+                frame[frameIndex++] = 6; // Opcodes.UNINITIALIZED_THIS;
+            }
+        }
+        int i = 1;
+        loop: while (true) {
+            int j = i;
+            switch (descriptor.charAt(i++)) {
+            case 'Z':
+            case 'C':
+            case 'B':
+            case 'S':
+            case 'I':
+                frame[frameIndex++] = 1; // Opcodes.INTEGER;
+                break;
+            case 'F':
+                frame[frameIndex++] = 2; // Opcodes.FLOAT;
+                break;
+            case 'J':
+                frame[frameIndex++] = 4; // Opcodes.LONG;
+                break;
+            case 'D':
+                frame[frameIndex++] = 3; // Opcodes.DOUBLE;
+                break;
+            case '[':
+                while (descriptor.charAt(i) == '[') {
+                    ++i;
+                }
+                if (descriptor.charAt(i) == 'L') {
+                    ++i;
+                    while (descriptor.charAt(i) != ';') {
+                        ++i;
+                    }
+                }
+                frame[frameIndex++] = Frame.OBJECT
+                        | cw.addType(descriptor.substring(j, ++i));
+                break;
+            case 'L':
+                while (descriptor.charAt(i) != ';') {
+                    ++i;
+                }
+                frame[frameIndex++] = Frame.OBJECT
+                        | cw.addType(descriptor.substring(j + 1, i++));
+                break;
+            default:
+                break loop;
+            }
+        }
+        frame[1] = frameIndex - 3;
+        endFrame();
+    }
+
+    /**
+     * Starts the visit of a stack map frame.
+     * 
+     * @param offset
+     *            the offset of the instruction to which the frame corresponds.
+     * @param nLocal
+     *            the number of local variables in the frame.
+     * @param nStack
+     *            the number of stack elements in the frame.
+     * @return the index of the next element to be written in this frame.
+     */
+    private int startFrame(final int offset, final int nLocal, final int nStack) {
+        int n = 3 + nLocal + nStack;
+        if (frame == null || frame.length < n) {
+            frame = new int[n];
+        }
+        frame[0] = offset;
+        frame[1] = nLocal;
+        frame[2] = nStack;
+        return 3;
+    }
+
+    /**
+     * Checks if the visit of the current frame {@link #frame} is finished, and
+     * if yes, write it in the StackMapTable attribute.
+     */
+    private void endFrame() {
+        if (previousFrame != null) { // do not write the first frame
+            if (stackMap == null) {
+                stackMap = new ByteVector();
+            }
+            writeFrame();
+            ++frameCount;
+        }
+        previousFrame = frame;
+        frame = null;
+    }
+
+    /**
+     * Compress and writes the current frame {@link #frame} in the StackMapTable
+     * attribute.
+     */
+    private void writeFrame() {
+        int clocalsSize = frame[1];
+        int cstackSize = frame[2];
+        if ((cw.version & 0xFFFF) < Opcodes.V1_6) {
+            stackMap.putShort(frame[0]).putShort(clocalsSize);
+            writeFrameTypes(3, 3 + clocalsSize);
+            stackMap.putShort(cstackSize);
+            writeFrameTypes(3 + clocalsSize, 3 + clocalsSize + cstackSize);
+            return;
+        }
+        int localsSize = previousFrame[1];
+        int type = FULL_FRAME;
+        int k = 0;
+        int delta;
+        if (frameCount == 0) {
+            delta = frame[0];
+        } else {
+            delta = frame[0] - previousFrame[0] - 1;
+        }
+        if (cstackSize == 0) {
+            k = clocalsSize - localsSize;
+            switch (k) {
+            case -3:
+            case -2:
+            case -1:
+                type = CHOP_FRAME;
+                localsSize = clocalsSize;
+                break;
+            case 0:
+                type = delta < 64 ? SAME_FRAME : SAME_FRAME_EXTENDED;
+                break;
+            case 1:
+            case 2:
+            case 3:
+                type = APPEND_FRAME;
+                break;
+            }
+        } else if (clocalsSize == localsSize && cstackSize == 1) {
+            type = delta < 63 ? SAME_LOCALS_1_STACK_ITEM_FRAME
+                    : SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED;
+        }
+        if (type != FULL_FRAME) {
+            // verify if locals are the same
+            int l = 3;
+            for (int j = 0; j < localsSize; j++) {
+                if (frame[l] != previousFrame[l]) {
+                    type = FULL_FRAME;
+                    break;
+                }
+                l++;
+            }
+        }
+        switch (type) {
+        case SAME_FRAME:
+            stackMap.putByte(delta);
+            break;
+        case SAME_LOCALS_1_STACK_ITEM_FRAME:
+            stackMap.putByte(SAME_LOCALS_1_STACK_ITEM_FRAME + delta);
+            writeFrameTypes(3 + clocalsSize, 4 + clocalsSize);
+            break;
+        case SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED:
+            stackMap.putByte(SAME_LOCALS_1_STACK_ITEM_FRAME_EXTENDED).putShort(
+                    delta);
+            writeFrameTypes(3 + clocalsSize, 4 + clocalsSize);
+            break;
+        case SAME_FRAME_EXTENDED:
+            stackMap.putByte(SAME_FRAME_EXTENDED).putShort(delta);
+            break;
+        case CHOP_FRAME:
+            stackMap.putByte(SAME_FRAME_EXTENDED + k).putShort(delta);
+            break;
+        case APPEND_FRAME:
+            stackMap.putByte(SAME_FRAME_EXTENDED + k).putShort(delta);
+            writeFrameTypes(3 + localsSize, 3 + clocalsSize);
+            break;
+        // case FULL_FRAME:
+        default:
+            stackMap.putByte(FULL_FRAME).putShort(delta).putShort(clocalsSize);
+            writeFrameTypes(3, 3 + clocalsSize);
+            stackMap.putShort(cstackSize);
+            writeFrameTypes(3 + clocalsSize, 3 + clocalsSize + cstackSize);
+        }
+    }
+
+    /**
+     * Writes some types of the current frame {@link #frame} into the
+     * StackMapTableAttribute. This method converts types from the format used
+     * in {@link Label} to the format used in StackMapTable attributes. In
+     * particular, it converts type table indexes to constant pool indexes.
+     * 
+     * @param start
+     *            index of the first type in {@link #frame} to write.
+     * @param end
+     *            index of last type in {@link #frame} to write (exclusive).
+     */
+    private void writeFrameTypes(final int start, final int end) {
+        for (int i = start; i < end; ++i) {
+            int t = frame[i];
+            int d = t & Frame.DIM;
+            if (d == 0) {
+                int v = t & Frame.BASE_VALUE;
+                switch (t & Frame.BASE_KIND) {
+                case Frame.OBJECT:
+                    stackMap.putByte(7).putShort(
+                            cw.newClass(cw.typeTable[v].strVal1));
+                    break;
+                case Frame.UNINITIALIZED:
+                    stackMap.putByte(8).putShort(cw.typeTable[v].intVal);
+                    break;
+                default:
+                    stackMap.putByte(v);
+                }
+            } else {
+                StringBuffer buf = new StringBuffer();
+                d >>= 28;
+                while (d-- > 0) {
+                    buf.append('[');
+                }
+                if ((t & Frame.BASE_KIND) == Frame.OBJECT) {
+                    buf.append('L');
+                    buf.append(cw.typeTable[t & Frame.BASE_VALUE].strVal1);
+                    buf.append(';');
+                } else {
+                    switch (t & 0xF) {
+                    case 1:
+                        buf.append('I');
+                        break;
+                    case 2:
+                        buf.append('F');
+                        break;
+                    case 3:
+                        buf.append('D');
+                        break;
+                    case 9:
+                        buf.append('Z');
+                        break;
+                    case 10:
+                        buf.append('B');
+                        break;
+                    case 11:
+                        buf.append('C');
+                        break;
+                    case 12:
+                        buf.append('S');
+                        break;
+                    default:
+                        buf.append('J');
+                    }
+                }
+                stackMap.putByte(7).putShort(cw.newClass(buf.toString()));
+            }
+        }
+    }
+
+    private void writeFrameType(final Object type) {
+        if (type instanceof String) {
+            stackMap.putByte(7).putShort(cw.newClass((String) type));
+        } else if (type instanceof Integer) {
+            stackMap.putByte(((Integer) type).intValue());
+        } else {
+            stackMap.putByte(8).putShort(((Label) type).position);
+        }
+    }
+
+    // ------------------------------------------------------------------------
+    // Utility methods: dump bytecode array
+    // ------------------------------------------------------------------------
+
+    /**
+     * Returns the size of the bytecode of this method.
+     * 
+     * @return the size of the bytecode of this method.
+     */
+    final int getSize() {
+        if (classReaderOffset != 0) {
+            return 6 + classReaderLength;
+        }
+        if (resize) {
+            // replaces the temporary jump opcodes introduced by Label.resolve.
+            if (ClassReader.RESIZE) {
+                resizeInstructions();
+            } else {
+                throw new RuntimeException("Method code too large!");
+            }
+        }
+        int size = 8;
+        if (code.length > 0) {
+            if (code.length > 65536) {
+                throw new RuntimeException("Method code too large!");
+            }
+            cw.newUTF8("Code");
+            size += 18 + code.length + 8 * handlerCount;
+            if (localVar != null) {
+                cw.newUTF8("LocalVariableTable");
+                size += 8 + localVar.length;
+            }
+            if (localVarType != null) {
+                cw.newUTF8("LocalVariableTypeTable");
+                size += 8 + localVarType.length;
+            }
+            if (lineNumber != null) {
+                cw.newUTF8("LineNumberTable");
+                size += 8 + lineNumber.length;
+            }
+            if (stackMap != null) {
+                boolean zip = (cw.version & 0xFFFF) >= Opcodes.V1_6;
+                cw.newUTF8(zip ? "StackMapTable" : "StackMap");
+                size += 8 + stackMap.length;
+            }
+            if (cattrs != null) {
+                size += cattrs.getSize(cw, code.data, code.length, maxStack,
+                        maxLocals);
+            }
+        }
+        if (exceptionCount > 0) {
+            cw.newUTF8("Exceptions");
+            size += 8 + 2 * exceptionCount;
+        }
+        if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
+            if ((cw.version & 0xFFFF) < Opcodes.V1_5
+                    || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0) {
+                cw.newUTF8("Synthetic");
+                size += 6;
+            }
+        }
+        if ((access & Opcodes.ACC_DEPRECATED) != 0) {
+            cw.newUTF8("Deprecated");
+            size += 6;
+        }
+        if (ClassReader.SIGNATURES && signature != null) {
+            cw.newUTF8("Signature");
+            cw.newUTF8(signature);
+            size += 8;
+        }
+        if (ClassReader.ANNOTATIONS && annd != null) {
+            cw.newUTF8("AnnotationDefault");
+            size += 6 + annd.length;
+        }
+        if (ClassReader.ANNOTATIONS && anns != null) {
+            cw.newUTF8("RuntimeVisibleAnnotations");
+            size += 8 + anns.getSize();
+        }
+        if (ClassReader.ANNOTATIONS && ianns != null) {
+            cw.newUTF8("RuntimeInvisibleAnnotations");
+            size += 8 + ianns.getSize();
+        }
+        if (ClassReader.ANNOTATIONS && panns != null) {
+            cw.newUTF8("RuntimeVisibleParameterAnnotations");
+            size += 7 + 2 * (panns.length - synthetics);
+            for (int i = panns.length - 1; i >= synthetics; --i) {
+                size += panns[i] == null ? 0 : panns[i].getSize();
+            }
+        }
+        if (ClassReader.ANNOTATIONS && ipanns != null) {
+            cw.newUTF8("RuntimeInvisibleParameterAnnotations");
+            size += 7 + 2 * (ipanns.length - synthetics);
+            for (int i = ipanns.length - 1; i >= synthetics; --i) {
+                size += ipanns[i] == null ? 0 : ipanns[i].getSize();
+            }
+        }
+        if (attrs != null) {
+            size += attrs.getSize(cw, null, 0, -1, -1);
+        }
+        return size;
+    }
+
+    /**
+     * Puts the bytecode of this method in the given byte vector.
+     * 
+     * @param out
+     *            the byte vector into which the bytecode of this method must be
+     *            copied.
+     */
+    final void put(final ByteVector out) {
+        final int FACTOR = ClassWriter.TO_ACC_SYNTHETIC;
+        int mask = ACC_CONSTRUCTOR | Opcodes.ACC_DEPRECATED
+                | ClassWriter.ACC_SYNTHETIC_ATTRIBUTE
+                | ((access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) / FACTOR);
+        out.putShort(access & ~mask).putShort(name).putShort(desc);
+        if (classReaderOffset != 0) {
+            out.putByteArray(cw.cr.b, classReaderOffset, classReaderLength);
+            return;
+        }
+        int attributeCount = 0;
+        if (code.length > 0) {
+            ++attributeCount;
+        }
+        if (exceptionCount > 0) {
+            ++attributeCount;
+        }
+        if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
+            if ((cw.version & 0xFFFF) < Opcodes.V1_5
+                    || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0) {
+                ++attributeCount;
+            }
+        }
+        if ((access & Opcodes.ACC_DEPRECATED) != 0) {
+            ++attributeCount;
+        }
+        if (ClassReader.SIGNATURES && signature != null) {
+            ++attributeCount;
+        }
+        if (ClassReader.ANNOTATIONS && annd != null) {
+            ++attributeCount;
+        }
+        if (ClassReader.ANNOTATIONS && anns != null) {
+            ++attributeCount;
+        }
+        if (ClassReader.ANNOTATIONS && ianns != null) {
+            ++attributeCount;
+        }
+        if (ClassReader.ANNOTATIONS && panns != null) {
+            ++attributeCount;
+        }
+        if (ClassReader.ANNOTATIONS && ipanns != null) {
+            ++attributeCount;
+        }
+        if (attrs != null) {
+            attributeCount += attrs.getCount();
+        }
+        out.putShort(attributeCount);
+        if (code.length > 0) {
+            int size = 12 + code.length + 8 * handlerCount;
+            if (localVar != null) {
+                size += 8 + localVar.length;
+            }
+            if (localVarType != null) {
+                size += 8 + localVarType.length;
+            }
+            if (lineNumber != null) {
+                size += 8 + lineNumber.length;
+            }
+            if (stackMap != null) {
+                size += 8 + stackMap.length;
+            }
+            if (cattrs != null) {
+                size += cattrs.getSize(cw, code.data, code.length, maxStack,
+                        maxLocals);
+            }
+            out.putShort(cw.newUTF8("Code")).putInt(size);
+            out.putShort(maxStack).putShort(maxLocals);
+            out.putInt(code.length).putByteArray(code.data, 0, code.length);
+            out.putShort(handlerCount);
+            if (handlerCount > 0) {
+                Handler h = firstHandler;
+                while (h != null) {
+                    out.putShort(h.start.position).putShort(h.end.position)
+                            .putShort(h.handler.position).putShort(h.type);
+                    h = h.next;
+                }
+            }
+            attributeCount = 0;
+            if (localVar != null) {
+                ++attributeCount;
+            }
+            if (localVarType != null) {
+                ++attributeCount;
+            }
+            if (lineNumber != null) {
+                ++attributeCount;
+            }
+            if (stackMap != null) {
+                ++attributeCount;
+            }
+            if (cattrs != null) {
+                attributeCount += cattrs.getCount();
+            }
+            out.putShort(attributeCount);
+            if (localVar != null) {
+                out.putShort(cw.newUTF8("LocalVariableTable"));
+                out.putInt(localVar.length + 2).putShort(localVarCount);
+                out.putByteArray(localVar.data, 0, localVar.length);
+            }
+            if (localVarType != null) {
+                out.putShort(cw.newUTF8("LocalVariableTypeTable"));
+                out.putInt(localVarType.length + 2).putShort(localVarTypeCount);
+                out.putByteArray(localVarType.data, 0, localVarType.length);
+            }
+            if (lineNumber != null) {
+                out.putShort(cw.newUTF8("LineNumberTable"));
+                out.putInt(lineNumber.length + 2).putShort(lineNumberCount);
+                out.putByteArray(lineNumber.data, 0, lineNumber.length);
+            }
+            if (stackMap != null) {
+                boolean zip = (cw.version & 0xFFFF) >= Opcodes.V1_6;
+                out.putShort(cw.newUTF8(zip ? "StackMapTable" : "StackMap"));
+                out.putInt(stackMap.length + 2).putShort(frameCount);
+                out.putByteArray(stackMap.data, 0, stackMap.length);
+            }
+            if (cattrs != null) {
+                cattrs.put(cw, code.data, code.length, maxLocals, maxStack, out);
+            }
+        }
+        if (exceptionCount > 0) {
+            out.putShort(cw.newUTF8("Exceptions")).putInt(
+                    2 * exceptionCount + 2);
+            out.putShort(exceptionCount);
+            for (int i = 0; i < exceptionCount; ++i) {
+                out.putShort(exceptions[i]);
+            }
+        }
+        if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
+            if ((cw.version & 0xFFFF) < Opcodes.V1_5
+                    || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0) {
+                out.putShort(cw.newUTF8("Synthetic")).putInt(0);
+            }
+        }
+        if ((access & Opcodes.ACC_DEPRECATED) != 0) {
+            out.putShort(cw.newUTF8("Deprecated")).putInt(0);
+        }
+        if (ClassReader.SIGNATURES && signature != null) {
+            out.putShort(cw.newUTF8("Signature")).putInt(2)
+                    .putShort(cw.newUTF8(signature));
+        }
+        if (ClassReader.ANNOTATIONS && annd != null) {
+            out.putShort(cw.newUTF8("AnnotationDefault"));
+            out.putInt(annd.length);
+            out.putByteArray(annd.data, 0, annd.length);
+        }
+        if (ClassReader.ANNOTATIONS && anns != null) {
+            out.putShort(cw.newUTF8("RuntimeVisibleAnnotations"));
+            anns.put(out);
+        }
+        if (ClassReader.ANNOTATIONS && ianns != null) {
+            out.putShort(cw.newUTF8("RuntimeInvisibleAnnotations"));
+            ianns.put(out);
+        }
+        if (ClassReader.ANNOTATIONS && panns != null) {
+            out.putShort(cw.newUTF8("RuntimeVisibleParameterAnnotations"));
+            AnnotationWriter.put(panns, synthetics, out);
+        }
+        if (ClassReader.ANNOTATIONS && ipanns != null) {
+            out.putShort(cw.newUTF8("RuntimeInvisibleParameterAnnotations"));
+            AnnotationWriter.put(ipanns, synthetics, out);
+        }
+        if (attrs != null) {
+            attrs.put(cw, null, 0, -1, -1, out);
+        }
+    }
+
+    // ------------------------------------------------------------------------
+    // Utility methods: instruction resizing (used to handle GOTO_W and JSR_W)
+    // ------------------------------------------------------------------------
+
+    /**
+     * Resizes and replaces the temporary instructions inserted by
+     * {@link Label#resolve} for wide forward jumps, while keeping jump offsets
+     * and instruction addresses consistent. This may require to resize other
+     * existing instructions, or even to introduce new instructions: for
+     * example, increasing the size of an instruction by 2 at the middle of a
+     * method can increases the offset of an IFEQ instruction from 32766 to
+     * 32768, in which case IFEQ 32766 must be replaced with IFNEQ 8 GOTO_W
+     * 32765. This, in turn, may require to increase the size of another jump
+     * instruction, and so on... All these operations are handled automatically
+     * by this method.
+     * <p>
+     * <i>This method must be called after all the method that is being built
+     * has been visited</i>. In particular, the {@link Label Label} objects used
+     * to construct the method are no longer valid after this method has been
+     * called.
+     */
+    private void resizeInstructions() {
+        byte[] b = code.data; // bytecode of the method
+        int u, v, label; // indexes in b
+        int i, j; // loop indexes
+        /*
+         * 1st step: As explained above, resizing an instruction may require to
+         * resize another one, which may require to resize yet another one, and
+         * so on. The first step of the algorithm consists in finding all the
+         * instructions that need to be resized, without modifying the code.
+         * This is done by the following "fix point" algorithm:
+         * 
+         * Parse the code to find the jump instructions whose offset will need
+         * more than 2 bytes to be stored (the future offset is computed from
+         * the current offset and from the number of bytes that will be inserted
+         * or removed between the source and target instructions). For each such
+         * instruction, adds an entry in (a copy of) the indexes and sizes
+         * arrays (if this has not already been done in a previous iteration!).
+         * 
+         * If at least one entry has been added during the previous step, go
+         * back to the beginning, otherwise stop.
+         * 
+         * In fact the real algorithm is complicated by the fact that the size
+         * of TABLESWITCH and LOOKUPSWITCH instructions depends on their
+         * position in the bytecode (because of padding). In order to ensure the
+         * convergence of the algorithm, the number of bytes to be added or
+         * removed from these instructions is over estimated during the previous
+         * loop, and computed exactly only after the loop is finished (this
+         * requires another pass to parse the bytecode of the method).
+         */
+        int[] allIndexes = new int[0]; // copy of indexes
+        int[] allSizes = new int[0]; // copy of sizes
+        boolean[] resize; // instructions to be resized
+        int newOffset; // future offset of a jump instruction
+
+        resize = new boolean[code.length];
+
+        // 3 = loop again, 2 = loop ended, 1 = last pass, 0 = done
+        int state = 3;
+        do {
+            if (state == 3) {
+                state = 2;
+            }
+            u = 0;
+            while (u < b.length) {
+                int opcode = b[u] & 0xFF; // opcode of current instruction
+                int insert = 0; // bytes to be added after this instruction
+
+                switch (ClassWriter.TYPE[opcode]) {
+                case ClassWriter.NOARG_INSN:
+                case ClassWriter.IMPLVAR_INSN:
+                    u += 1;
+                    break;
+                case ClassWriter.LABEL_INSN:
+                    if (opcode > 201) {
+                        // converts temporary opcodes 202 to 217, 218 and
+                        // 219 to IFEQ ... JSR (inclusive), IFNULL and
+                        // IFNONNULL
+                        opcode = opcode < 218 ? opcode - 49 : opcode - 20;
+                        label = u + readUnsignedShort(b, u + 1);
+                    } else {
+                        label = u + readShort(b, u + 1);
+                    }
+                    newOffset = getNewOffset(allIndexes, allSizes, u, label);
+                    if (newOffset < Short.MIN_VALUE
+                            || newOffset > Short.MAX_VALUE) {
+                        if (!resize[u]) {
+                            if (opcode == Opcodes.GOTO || opcode == Opcodes.JSR) {
+                                // two additional bytes will be required to
+                                // replace this GOTO or JSR instruction with
+                                // a GOTO_W or a JSR_W
+                                insert = 2;
+                            } else {
+                                // five additional bytes will be required to
+                                // replace this IFxxx <l> instruction with
+                                // IFNOTxxx <l'> GOTO_W <l>, where IFNOTxxx
+                                // is the "opposite" opcode of IFxxx (i.e.,
+                                // IFNE for IFEQ) and where <l'> designates
+                                // the instruction just after the GOTO_W.
+                                insert = 5;
+                            }
+                            resize[u] = true;
+                        }
+                    }
+                    u += 3;
+                    break;
+                case ClassWriter.LABELW_INSN:
+                    u += 5;
+                    break;
+                case ClassWriter.TABL_INSN:
+                    if (state == 1) {
+                        // true number of bytes to be added (or removed)
+                        // from this instruction = (future number of padding
+                        // bytes - current number of padding byte) -
+                        // previously over estimated variation =
+                        // = ((3 - newOffset%4) - (3 - u%4)) - u%4
+                        // = (-newOffset%4 + u%4) - u%4
+                        // = -(newOffset & 3)
+                        newOffset = getNewOffset(allIndexes, allSizes, 0, u);
+                        insert = -(newOffset & 3);
+                    } else if (!resize[u]) {
+                        // over estimation of the number of bytes to be
+                        // added to this instruction = 3 - current number
+                        // of padding bytes = 3 - (3 - u%4) = u%4 = u & 3
+                        insert = u & 3;
+                        resize[u] = true;
+                    }
+                    // skips instruction
+                    u = u + 4 - (u & 3);
+                    u += 4 * (readInt(b, u + 8) - readInt(b, u + 4) + 1) + 12;
+                    break;
+                case ClassWriter.LOOK_INSN:
+                    if (state == 1) {
+                        // like TABL_INSN
+                        newOffset = getNewOffset(allIndexes, allSizes, 0, u);
+                        insert = -(newOffset & 3);
+                    } else if (!resize[u]) {
+                        // like TABL_INSN
+                        insert = u & 3;
+                        resize[u] = true;
+                    }
+                    // skips instruction
+                    u = u + 4 - (u & 3);
+                    u += 8 * readInt(b, u + 4) + 8;
+                    break;
+                case ClassWriter.WIDE_INSN:
+                    opcode = b[u + 1] & 0xFF;
+                    if (opcode == Opcodes.IINC) {
+                        u += 6;
+                    } else {
+                        u += 4;
+                    }
+                    break;
+                case ClassWriter.VAR_INSN:
+                case ClassWriter.SBYTE_INSN:
+                case ClassWriter.LDC_INSN:
+                    u += 2;
+                    break;
+        

<TRUNCATED>

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