Example usage for org.objectweb.asm.tree MethodNode MethodNode

List of usage examples for org.objectweb.asm.tree MethodNode MethodNode

Introduction

In this page you can find the example usage for org.objectweb.asm.tree MethodNode MethodNode.

Prototype

public MethodNode() 

Source Link

Document

Constructs an uninitialized MethodNode .

Usage

From source file:org.lenskit.data.entities.AbstractBeanEntityBuilder.java

License:Open Source License

private static MethodNode generateLongSetter(Class<? extends AbstractBeanEntityBuilder> type, Method smethod) {
    MethodNode setter = new MethodNode();
    setter.access = ACC_PUBLIC;//from  w  ww.j  av  a2s.c  o m
    setter.desc = getMethodDescriptor(VOID_TYPE, getType(AbstractBeanEntityBuilder.class), getType(long.class));
    setter.name = "set";
    setter.exceptions = Collections.emptyList();
    setter.maxLocals = 4;
    setter.maxStack = 3;
    // load target object
    setter.visitVarInsn(ALOAD, 1);
    // cast target object
    setter.visitTypeInsn(CHECKCAST, getInternalName(type));
    // load attribute value
    setter.visitVarInsn(LLOAD, 2);
    // call real setter
    setter.visitMethodInsn(INVOKEVIRTUAL, getInternalName(type), smethod.getName(),
            getMethodDescriptor(smethod), false);
    setter.visitInsn(RETURN);
    return setter;
}

From source file:org.lenskit.data.entities.AbstractBeanEntityBuilder.java

License:Open Source License

private static MethodNode generateDoubleSetter(Class<? extends AbstractBeanEntityBuilder> type,
        Method smethod) {//from w ww  .  ja  v a2  s  .  c om
    MethodNode setter = new MethodNode();
    setter.access = ACC_PUBLIC;
    setter.desc = getMethodDescriptor(VOID_TYPE, getType(AbstractBeanEntityBuilder.class),
            getType(double.class));
    setter.name = "set";
    setter.exceptions = Collections.emptyList();
    setter.maxLocals = 4;
    setter.maxStack = 3;
    // load target object
    setter.visitVarInsn(ALOAD, 1);
    // cast target object
    setter.visitTypeInsn(CHECKCAST, getInternalName(type));
    // load attribute value
    setter.visitVarInsn(DLOAD, 2);
    // call real setter
    setter.visitMethodInsn(INVOKEVIRTUAL, getInternalName(type), smethod.getName(),
            getMethodDescriptor(smethod), false);
    setter.visitInsn(RETURN);
    return setter;
}

From source file:org.lenskit.data.entities.AbstractBeanEntityBuilder.java

License:Open Source License

private static MethodNode generateClearer(Class<? extends AbstractBeanEntityBuilder> type, Method smethod,
        Method cmethod) {/*from w w w  .  java  2 s  .  co m*/
    MethodNode clearer = new MethodNode();
    clearer.access = ACC_PUBLIC;
    clearer.desc = getMethodDescriptor(VOID_TYPE, getType(AbstractBeanEntityBuilder.class));
    clearer.name = "clear";
    clearer.exceptions = Collections.emptyList();
    clearer.maxLocals = 2;
    clearer.maxStack = 1;
    if (cmethod != null) {
        // load target object
        clearer.visitVarInsn(ALOAD, 1);
        // cast to target object type
        clearer.visitTypeInsn(CHECKCAST, getInternalName(type));
        // call clearer method
        clearer.visitMethodInsn(INVOKEVIRTUAL, getInternalName(type), cmethod.getName(),
                getMethodDescriptor(cmethod), false);
        clearer.visitInsn(RETURN);
    } else if (!smethod.getParameterTypes()[0].isPrimitive()) {
        // load target object & cast to type
        clearer.visitVarInsn(ALOAD, 1);
        clearer.visitTypeInsn(CHECKCAST, getInternalName(type));
        // load null and call setter
        clearer.visitInsn(ACONST_NULL);
        clearer.maxStack = 2;
        clearer.visitMethodInsn(INVOKEVIRTUAL, getInternalName(type), smethod.getName(),
                getMethodDescriptor(smethod), false);
        clearer.visitInsn(RETURN);
    } else {
        // no clearer and primitive method, throw unsupported operation exception
        clearer.maxStack = 2;
        clearer.visitTypeInsn(NEW, "java/lang/UnsupportedOperationException");
        clearer.visitInsn(DUP);
        clearer.visitMethodInsn(INVOKESPECIAL, "java/lang/UnsupportedOperationException", "<init>", "()V",
                false);
        clearer.visitInsn(ATHROW);
    }
    return clearer;
}

From source file:pl.clareo.coroutines.core.ClassTransformer.java

License:Apache License

@SuppressWarnings("unchecked")
void transform() {
    for (MethodNode coroutine : coroutines) {
        if (log.isLoggable(Level.FINEST)) {
            log.finest("Generating method for coroutine " + coroutine.name + coroutine.desc);
        }/*  w  ww .  j  a va 2 s . c  om*/
        String coroutineName = getCoroutineName(coroutine);
        MethodTransformer methodTransformer = new MethodTransformer(coroutine, thisType);
        MethodNode coroutineImpl = methodTransformer.transform(coroutineName, generateDebugCode);
        thisNode.methods.add(coroutineImpl);
        /*
         * generate co iterators and method stubs
         */
        log.finest("Generating CoIterator implementation and method stubs");
        String baseCoIteratorName;
        Map<String, Object> annotation = getCoroutineAnnotationValues(coroutine);
        if (getBoolean(annotation, "threadLocal")) {
            baseCoIteratorName = Type.getInternalName(ThreadLocalCoIterator.class);
        } else {
            baseCoIteratorName = Type.getInternalName(SingleThreadedCoIterator.class);
        }
        String coIteratorClassName = "pl/clareo/coroutines/core/CoIterator" + num;
        ClassNode coIteratorClass = new ClassNode();
        coIteratorClass.version = Opcodes.V1_6;
        coIteratorClass.access = Opcodes.ACC_PUBLIC | Opcodes.ACC_FINAL | Opcodes.ACC_SUPER;
        coIteratorClass.name = coIteratorClassName;
        coIteratorClass.superName = baseCoIteratorName;
        if (generateDebugCode) {
            /*
             * If debugging code is emitted create field keeping JDK logger
             */
            FieldNode loggerField = new FieldNode(Opcodes.ACC_PRIVATE | Opcodes.ACC_FINAL | Opcodes.ACC_STATIC,
                    "logger", "Ljava/util/logging/Logger;", null, null);
            coIteratorClass.fields.add(loggerField);
            MethodNode clinit = new MethodNode();
            clinit.access = Opcodes.ACC_STATIC;
            clinit.name = "<clinit>";
            clinit.desc = "()V";
            clinit.exceptions = Collections.EMPTY_LIST;
            String loggerName = thisType.getClassName();
            InsnList clinitCode = clinit.instructions;
            clinitCode.add(new LdcInsnNode(loggerName));
            clinitCode.add(new MethodInsnNode(Opcodes.INVOKESTATIC, "java/util/logging/Logger", "getLogger",
                    "(Ljava/lang/String;)Ljava/util/logging/Logger;"));
            clinitCode.add(new FieldInsnNode(Opcodes.PUTSTATIC, coIteratorClassName, "logger",
                    "Ljava/util/logging/Logger;"));
            clinitCode.add(new InsnNode(Opcodes.RETURN));
            clinit.maxStack = 1;
            clinit.maxLocals = 0;
            coIteratorClass.methods.add(clinit);
        }
        /*
         * Generate constructor
         */
        MethodNode init = new MethodNode();
        init.access = Opcodes.ACC_PUBLIC;
        init.name = "<init>";
        init.desc = CO_ITERATOR_CONSTRUCTOR_DESCRIPTOR;
        init.exceptions = Collections.EMPTY_LIST;
        InsnList initCode = init.instructions;
        initCode.add(new VarInsnNode(Opcodes.ALOAD, 0));
        initCode.add(new VarInsnNode(Opcodes.ALOAD, 1));
        initCode.add(new MethodInsnNode(Opcodes.INVOKESPECIAL, baseCoIteratorName, "<init>",
                CO_ITERATOR_CONSTRUCTOR_DESCRIPTOR));
        initCode.add(new InsnNode(Opcodes.RETURN));
        init.maxStack = 2;
        init.maxLocals = 2;
        coIteratorClass.methods.add(init);
        /*
         * Generate overriden call to coroutine
         */
        MethodNode call = new MethodNode();
        call.access = Opcodes.ACC_PROTECTED;
        call.name = "call";
        call.desc = CALL_METHOD_DESCRIPTOR;
        call.exceptions = Collections.EMPTY_LIST;
        InsnList callCode = call.instructions;
        /*
         * if debug needed generate call details
         */
        if (generateDebugCode) {
            String coroutineId = "Coroutine " + coroutine.name;
            callCode.add(loggingInstructions(coIteratorClassName, "logger", Level.FINER,
                    coroutineId + " call. Caller sent: ", 2));
            callCode.add(new FrameNode(Opcodes.F_SAME, 0, EMPTY_LOCALS, 0, EMPTY_STACK));
            callCode.add(loggingInstructions(coIteratorClassName, "logger", Level.FINEST,
                    coroutineId + " state ", 1));
            callCode.add(new FrameNode(Opcodes.F_SAME, 0, EMPTY_LOCALS, 0, EMPTY_STACK));
        }
        /*
         * push call arguments: this (if not static), frame, input, output
         */
        boolean isStatic = (coroutine.access & Opcodes.ACC_STATIC) != 0;
        if (!isStatic) {
            callCode.add(new VarInsnNode(Opcodes.ALOAD, 1));
            callCode.add(
                    new MethodInsnNode(Opcodes.INVOKEVIRTUAL, FRAME_NAME, "getThis", "()Ljava/lang/Object;"));
            callCode.add(new TypeInsnNode(Opcodes.CHECKCAST, thisType.getInternalName()));
        }
        callCode.add(new VarInsnNode(Opcodes.ALOAD, 1));
        callCode.add(new InsnNode(Opcodes.ACONST_NULL));
        callCode.add(new VarInsnNode(Opcodes.ALOAD, 2));
        callCode.add(new MethodInsnNode(isStatic ? Opcodes.INVOKESTATIC : Opcodes.INVOKEVIRTUAL,
                thisType.getInternalName(), coroutineName, COROUTINE_METHOD_DESCRIPTOR));
        // stack: *
        if (!generateDebugCode) {
            callCode.add(new InsnNode(Opcodes.ARETURN));
        } else {
            // save result display suspension point (two more locals
            // needed)
            callCode.add(new VarInsnNode(Opcodes.ASTORE, 3));
            callCode.add(new VarInsnNode(Opcodes.ALOAD, 1));
            callCode.add(new MethodInsnNode(Opcodes.INVOKEVIRTUAL, FRAME_NAME, "getLineOfCode", "()I"));
            callCode.add(box_int(Type.INT));
            callCode.add(new VarInsnNode(Opcodes.ASTORE, 4));
            callCode.add(loggingInstructions(coIteratorClassName, "logger", Level.FINER,
                    "Coroutine suspended at line ", 4, ". Yielded:", 3));
            callCode.add(new FrameNode(Opcodes.F_APPEND, 2,
                    new Object[] { "java/lang/Object", "java/lang/Integer" }, 0, EMPTY_STACK));
            callCode.add(new VarInsnNode(Opcodes.ALOAD, 3));
            callCode.add(new InsnNode(Opcodes.ARETURN));
        }
        coIteratorClass.methods.add(call);
        // if debugging code is emitted it needs space for two
        // additional locals and 5 stack operand
        if (generateDebugCode) {
            call.maxStack = 5;
            call.maxLocals = 5;
        } else {
            if (isStatic) {
                call.maxStack = 3;
            } else {
                call.maxStack = 4;
            }
            call.maxLocals = 3;
        }
        /*
         * CoIterator created - define it in the runtime and verify if
         * needed
         */
        if (log.isLoggable(Level.FINEST)) {
            log.finest("Generated class " + coIteratorClassName);
        }
        ClassWriter cw = new ClassWriter(0);
        coIteratorClass.accept(cw);
        byte[] classBytes = cw.toByteArray();
        try {
            CoroutineInstrumentator.dumpClass(coIteratorClassName, classBytes);
        } catch (IOException e) {
            throw new CoroutineGenerationException("Unable to write class " + coIteratorClassName, e);
        }
        /*
         * start generating method - new method is named as the method in
         * user code, it: returns instance of appropriate CoIterator (see
         * above), saves arguments of call
         */
        if (log.isLoggable(Level.FINEST)) {
            log.finest("Instrumenting method " + coroutine.name);
        }
        InsnList code = coroutine.instructions;
        code.clear();
        /*
         * create new Frame
         */
        boolean isDebugFramePossible = generateDebugCode && coroutine.localVariables != null;
        if (isDebugFramePossible) {
            code.add(createDebugFrame(coroutine));
        } else {
            code.add(createFrame(coroutine));
        }
        /*
         * save frame in the first, and locals array in the second local
         * variable
         */
        int argsSize = Type.getArgumentsAndReturnSizes(coroutine.desc) >> 2;
        if (isStatic) {
            argsSize -= 1;
        }
        code.add(new VarInsnNode(Opcodes.ASTORE, argsSize));
        code.add(new VarInsnNode(Opcodes.ALOAD, argsSize));
        code.add(new MethodInsnNode(Opcodes.INVOKEVIRTUAL, FRAME_NAME, "getLocals", "()[Ljava/lang/Object;"));
        int localsArrayIndex = argsSize + 1;
        code.add(new VarInsnNode(Opcodes.ASTORE, localsArrayIndex));
        /*
         * save all call arguments (along with this if this method is not
         * static) into locals array
         */
        Type[] argsTypes = Type.getArgumentTypes(coroutine.desc);
        if (!isStatic) {
            code.add(saveloc(localsArrayIndex, 0, 0, JAVA_LANG_OBJECT));
            code.add(savelocs(localsArrayIndex, 1, 1, argsTypes));
        } else {
            code.add(savelocs(localsArrayIndex, 0, 0, argsTypes));
        }
        /*
         * create CoIterator instance with saved frame, make initial call to
         * next if needed and return to caller
         */
        code.add(new TypeInsnNode(Opcodes.NEW, coIteratorClassName));
        code.add(new InsnNode(Opcodes.DUP));
        code.add(new VarInsnNode(Opcodes.ALOAD, argsSize));
        code.add(new MethodInsnNode(Opcodes.INVOKESPECIAL, coIteratorClassName, "<init>",
                CO_ITERATOR_CONSTRUCTOR_DESCRIPTOR));
        if (!getBoolean(annotation, "generator", true)) {
            code.add(new InsnNode(Opcodes.DUP));
            code.add(new MethodInsnNode(Opcodes.INVOKEVIRTUAL, coIteratorClassName, "next",
                    "()Ljava/lang/Object;"));
            code.add(new InsnNode(Opcodes.POP));
        }
        code.add(new InsnNode(Opcodes.ARETURN));
        /*
         * end method generation; maxs can be statically determined 3
         * operands on stack (call to frame setLocals and CoIterator
         * constructor) + 1 if any argument is long or double (debug frame
         * needs 7 operands for variable names creation); locals = argsSize
         * + 1 reference to frame + 1 array of locals
         */
        if (isDebugFramePossible) {
            coroutine.maxStack = 7;
        } else {
            boolean isCategory2ArgumentPresent = false;
            for (Type argType : argsTypes) {
                int sort = argType.getSort();
                if (sort == Type.LONG || sort == Type.DOUBLE) {
                    isCategory2ArgumentPresent = true;
                    break;
                }
            }
            coroutine.maxStack = isCategory2ArgumentPresent ? 4 : 3;
        }
        coroutine.maxLocals = localsArrayIndex + 1;
        coroutine.localVariables.clear();
        coroutine.tryCatchBlocks.clear();
        num++;
    }
}

From source file:pl.clareo.coroutines.core.MethodTransformer.java

License:Apache License

@SuppressWarnings("unchecked")
MethodNode transform(String coroutineName, boolean generateDebugCode) {
    MethodNode transformedMethod = new MethodNode();
    transformedMethod.access = ACC_PUBLIC | ACC_FINAL | (method.access & ACC_STATIC);
    transformedMethod.name = coroutineName;
    transformedMethod.desc = COROUTINE_METHOD_DESCRIPTOR;
    transformedMethod.exceptions = method.exceptions;
    final InsnList newCode = transformedMethod.instructions;
    Analyzer analyzer = new Analyzer(new BasicInterpreter() {

        @Override//from w  w  w  .  jav a  2 s.  c o m
        public Value binaryOperation(AbstractInsnNode insn, Value value1, Value value2)
                throws AnalyzerException {
            if (insn.getOpcode() == AALOAD) {
                return new BasicValue(((BasicValue) value1).getType().getElementType());
            }
            return super.binaryOperation(insn, value1, value2);
        };

        @Override
        public Value merge(Value v, Value w) {
            if (v == NULL_VALUE) {
                BasicValue w1 = (BasicValue) w;
                if (w1.isReference()) {
                    return w1;
                }
            }
            if (w == NULL_VALUE) {
                BasicValue v1 = (BasicValue) v;
                if (v1.isReference())
                    return v1;
            }
            if (!v.equals(w)) {
                BasicValue v1 = (BasicValue) v;
                BasicValue w1 = (BasicValue) w;
                if (v1.isReference() & w1.isReference()) {
                    Class<?> c1;
                    Class<?> c2;
                    try {
                        c1 = MethodTransformer.getClass(v1);
                        c2 = MethodTransformer.getClass(w1);
                    } catch (ClassNotFoundException e) {
                        throw new CoroutineGenerationException(
                                "It was needed to load a class during transformation process but loading unexpectedly failed",
                                e);
                    }
                    if (c1.isAssignableFrom(c2)) {
                        return v;
                    }
                    if (c2.isAssignableFrom(c1)) {
                        return w;
                    }
                }
            } else {
                return v;
            }
            return BasicValue.UNINITIALIZED_VALUE;
        }

        @Override
        public Value newValue(Type type) {
            if (type != null) {
                int typeSort = type.getSort();
                switch (typeSort) {
                case Type.VOID:
                    return NULL_VALUE;
                case Type.BOOLEAN:
                case Type.CHAR:
                case Type.BYTE:
                case Type.SHORT:
                case Type.INT:
                    return BasicValue.INT_VALUE;
                case Type.FLOAT:
                    return BasicValue.FLOAT_VALUE;
                case Type.LONG:
                    return BasicValue.LONG_VALUE;
                case Type.DOUBLE:
                    return BasicValue.DOUBLE_VALUE;
                case Type.ARRAY:
                case Type.OBJECT:
                    if (type.getInternalName().equals("null")) {
                        return NULL_VALUE;
                    }
                    return new BasicValue(type);
                default:
                    throw new Error("Internal error");
                }
            }
            return BasicValue.UNINITIALIZED_VALUE;
        }
    });
    Frame[] frames;
    try {
        frames = analyzer.analyze(methodOwner, method);
    } catch (AnalyzerException e) {
        throw new CoroutineGenerationException(e);
    }
    InsnList code = method.instructions;
    final List<Integer> yields = new ArrayList<Integer>(8);
    /*
     * Copy instructions patching variable indexes and frames, remember
     * yield indexes
     */
    int ic = 0;
    Iterator<AbstractInsnNode> i = code.iterator();
    while (i.hasNext()) {
        AbstractInsnNode insn = i.next();
        switch (insn.getType()) {
        case AbstractInsnNode.FRAME:
            FrameNode frame = (FrameNode) insn.clone(labelsMap);
            // update values
            if (frame.type == F_FULL) {
                if (isStatic) {
                    frame.local.addAll(0, argsStackMapList);
                } else {
                    frame.local.addAll(1, argsStackMapList);
                }
            }
            newCode.add(frame);
            break;
        case AbstractInsnNode.IINC_INSN:
            IincInsnNode iinc = (IincInsnNode) insn.clone(labelsMap);
            iinc.var += variableIndexOffset;
            newCode.add(iinc);
            break;
        case AbstractInsnNode.INSN:
            switch (insn.getOpcode()) {
            case DRETURN:
            case FRETURN:
            case IRETURN:
            case LRETURN:
            case ARETURN:
            case RETURN:
                newCode.add(new InsnNode(POP));
                newCode.add(throwex("java/util/NoSuchElementException"));
                break;
            default:
                newCode.add(insn.clone(labelsMap));
            }
            break;
        case AbstractInsnNode.JUMP_INSN:
            if (insn.getOpcode() == JSR) {
                throw new CoroutineGenerationException("<jsr> not allowed");
            }
            JumpInsnNode jump = (JumpInsnNode) insn;
            LabelNode target = jump.label;
            if (!labelsMap.containsKey(target)) {
                labelsMap.put(target, new LabelNode());
            }
            newCode.add(jump.clone(labelsMap));
            break;
        case AbstractInsnNode.LABEL:
            if (!labelsMap.containsKey(insn)) {
                labelsMap.put((LabelNode) insn, new LabelNode());
            }
            newCode.add(insn.clone(labelsMap));
            break;
        case AbstractInsnNode.METHOD_INSN:
            if (insn.getOpcode() == INVOKESTATIC) {
                MethodInsnNode method = (MethodInsnNode) insn;
                if (method.owner.equals(COROUTINES_NAME)) {
                    String methodName = method.name;
                    if (methodName.equals("_")) {
                        /*
                         * a call to artificial CoIterator, since it is
                         * not needed after instrumentation we replace
                         * it with null. This null will be popped by
                         * corresponding ARETURN. Stack is not changed
                         */
                        newCode.add(new InsnNode(ACONST_NULL));
                        break;
                    }
                    if (methodName.equals("yield")) {
                        /*
                         * a call to yield - core of coroutine
                         * processing
                         */
                        yields.add(ic);
                    }
                }
            }
            newCode.add(insn.clone(labelsMap));
            break;
        case AbstractInsnNode.VAR_INSN:
            if (insn.getOpcode() == RET) {
                throw new CoroutineGenerationException("<ret> not allowed");
            }
            VarInsnNode var = (VarInsnNode) insn.clone(labelsMap);
            if (var.var != 0 || isStatic) {
                var.var += variableIndexOffset;
            }
            newCode.add(var);
            break;
        default:
            newCode.add(insn.clone(labelsMap));
            break;
        }
        ic += 1;
    }
    /*
     * patch yields in transformed code
     */
    final List<LabelNode> gotos = new ArrayList<LabelNode>(9);
    final Set<TryCatchBlockNode> patchedTryCatchBlocks = new HashSet<TryCatchBlockNode>();
    int yieldIndex = 0;
    i = newCode.iterator();
    while (i.hasNext()) {
        AbstractInsnNode insn = i.next();
        /*
         * track locals
         */
        int insnType = insn.getType();
        if (insnType == AbstractInsnNode.VAR_INSN) {
            int opcode = insn.getOpcode();
            if (opcode == ASTORE || opcode == DSTORE || opcode == LSTORE || opcode == ISTORE
                    || opcode == FSTORE) {
                int varIndex = ((VarInsnNode) insn).var - variableIndexOffset;
                finals[varIndex] = false;
            }
            continue;
        }
        /*
         * track line numbers
         */
        if (insnType == AbstractInsnNode.LINE) {
            lineNumber = ((LineNumberNode) insn).line;
            continue;
        }
        if (insnType != AbstractInsnNode.METHOD_INSN) {
            continue;
        }
        MethodInsnNode method = (MethodInsnNode) insn;
        if (!method.owner.equals(COROUTINES_NAME) || !method.name.equals("yield")) {
            continue;
        }
        InsnList yieldCode = new InsnList();
        int index = yields.get(yieldIndex);
        Frame f = frames[index];
        /*
         * a) operand on the top of stack is passed to the caller, we will
         * save it in 'in' parameter OR there is nothing to be passed to the
         * caller in case of yield() overload
         */
        boolean yieldWithArgument = Type.getArgumentTypes(method.desc).length != 0;
        boolean nonemptyStack;
        Type[] stackContents = null;
        int stackTop = 0;
        if (yieldWithArgument) {
            yieldCode.add(input(getStackTop(f)));
            nonemptyStack = f.getStackSize() > 1;
            stackTop = 1;
        } else {
            nonemptyStack = f.getStackSize() > 0;
        }
        /*
         * b) save remaining stack
         */
        if (nonemptyStack) {
            stackContents = getStackContents(f);
            // sanitize stack
            for (Type t : stackContents) {
                if (t == null) {
                    throw new CoroutineGenerationException(
                            "It is not possible to yield with uninitialized memory on the stack. Probably you use construct such as: new A(..,yield,..). Please move this yield call out of constructor");
                }
            }
            yieldCode.add(savestack(frame, stackContents, stackTop));
        }
        /*
         * c) save locals and state
         */
        Type[] locals = getLocals(f);
        yieldCode.add(saveLocals(locals));
        yieldCode.add(new VarInsnNode(ALOAD, frame));
        yieldCode.add(makeInt(++yieldIndex));
        yieldCode.add(new MethodInsnNode(INVOKEVIRTUAL, FRAME_NAME, "setState", "(I)V"));
        /*
         * d) jump to exit - in debug mode save line number
         */
        if (generateDebugCode) {
            yieldCode.add(new VarInsnNode(ALOAD, frame));
            yieldCode.add(makeInt(lineNumber));
            yieldCode.add(new MethodInsnNode(INVOKEVIRTUAL, FRAME_NAME, "setLineOfCode", "(I)V"));
        }
        yieldCode.add(new JumpInsnNode(GOTO, yieldLabel));
        /*
         * e) fix jump from switch statement
         */
        LabelNode jump = new LabelNode();
        gotos.add(jump);
        yieldCode.add(jump);
        yieldCode.add(emitCleanFrame());
        /*
         * f) check if exit condition occurs, load locals, restore stack and
         * stack map
         */
        yieldCode.add(new VarInsnNode(ALOAD, frame));
        yieldCode.add(new MethodInsnNode(INVOKEVIRTUAL, FRAME_NAME, "isCoroutineClosed", "()Z"));
        LabelNode continueHere = new LabelNode();
        yieldCode.add(new JumpInsnNode(IFEQ, continueHere));
        yieldCode.add(throwex(COROUTINE_EXIT_EXCEPTION));
        yieldCode.add(continueHere);
        yieldCode.add(new FrameNode(F_SAME, 0, EMPTY_LOCALS, 0, EMPTY_STACK));
        /*
         * find previous frame node, load locals then emit new frame node
         * and load rest
         */
        FrameNode prevFrame = findPreviousFrame(code.get(index));
        Type[] prevLocals;
        if (prevFrame != null) {
            Frame oldFrame = frames[code.indexOf(prevFrame)];
            prevLocals = getLocals(oldFrame);
        } else {
            prevLocals = getLocals(frames[0]);
        }
        yieldCode.add(restoreLocals(prevLocals));
        FrameNode frameNode = mergeFrames(getFrameTypes(prevLocals), null);
        if (frameNode.type != F_SAME) {
            // bug fix - when no locals are restored and the stack is empty
            // two frames are collapsed
            yieldCode.add(frameNode);
        }
        if (nonemptyStack) {
            yieldCode.add(loadstack(frame, stackContents, stackTop));
        }
        // restore temp locals in scope
        yieldCode.add(restoreLocals(diff(locals, prevLocals)));
        /*
         * push "sent" value
         */
        yieldCode.add(new VarInsnNode(ALOAD, out));
        newCode.insertBefore(method, yieldCode);
        /*
         * patch try catch blocks
         */
        List<TryCatchBlockNode> tryCatchBlocks = analyzer.getHandlers(index);
        if (tryCatchBlocks != null) {
            for (TryCatchBlockNode tryCatchBlock : tryCatchBlocks) {
                if (!patchedTryCatchBlocks.contains(tryCatchBlock)) {
                    LabelNode handler = tryCatchBlock.handler;
                    InsnList handlerPatch = new InsnList();
                    String exceptionType = tryCatchBlock.type == null ? "java/lang/Throwable"
                            : tryCatchBlock.type;
                    FrameNode catchFrame = emitCatchFrame(exceptionType);
                    handlerPatch.add(catchFrame);
                    Type[] ls = getLocals(frames[code.indexOf(handler)]);
                    handlerPatch.add(restoreLocals(ls));
                    handlerPatch.add(
                            mergeFrames(getFrameTypes(ls), new Type[] { Type.getObjectType(exceptionType) }));
                    patchedTryCatchBlocks.add(tryCatchBlock);
                    AbstractInsnNode newHandler = labelsMap.get(handler);
                    // remove "real" frame since it is not needed now
                    newCode.remove(findNextFrame(newHandler));
                    newCode.insert(newHandler, handlerPatch);
                }
            }
        }
        newCode.remove(method);
    }
    /*
     * copy local variables (wath out for indices change) and try catch
     * blocks to new method (clone)
     */
    List<TryCatchBlockNode> tryCatchBlocks = method.tryCatchBlocks;
    if (!tryCatchBlocks.isEmpty()) {
        transformedMethod.tryCatchBlocks = new ArrayList<TryCatchBlockNode>(tryCatchBlocks.size());
        for (TryCatchBlockNode tryCatchBlock : tryCatchBlocks) {
            transformedMethod.tryCatchBlocks.add(
                    new TryCatchBlockNode(labelsMap.get(tryCatchBlock.start), labelsMap.get(tryCatchBlock.end),
                            labelsMap.get(tryCatchBlock.handler), tryCatchBlock.type));
        }
    }
    if (method.localVariables != null) {
        List<LocalVariableNode> localVariables = method.localVariables;
        List<LocalVariableNode> newLocalVariables = new ArrayList<LocalVariableNode>(localVariables.size());
        for (LocalVariableNode localVariable : localVariables) {
            int newIndex = localVariable.index;
            if (newIndex != 0 || isStatic) {
                newIndex += variableIndexOffset;
            }
            newLocalVariables
                    .add(new LocalVariableNode(localVariable.name, localVariable.desc, localVariable.signature,
                            labelsMap.get(localVariable.start), labelsMap.get(localVariable.end), newIndex));
        }
        transformedMethod.localVariables = newLocalVariables;
    }
    newCode.insert(codeBefore(gotos));
    newCode.add(codeAfter());
    return transformedMethod;
}