Java Code Examples for org.objectweb.asm.commons.GeneratorAdapter#box()

/**
 * Given an array on the stack, it loads it with the values of the given variables stating at
 * offset.
 */
static void loadVariableArray(
        @NonNull GeneratorAdapter mv,
        @NonNull List<LocalVariable> variables, int offset) {
    // we need to maintain the stack index when loading parameters from, as for long and double
    // values, it uses 2 stack elements, all others use only 1 stack element.
    for (int i = offset; i < variables.size(); i++) {
        LocalVariable variable = variables.get(i);
        // duplicate the array of objects reference, it will be used to store the value in.
        mv.dup();
        // index in the array of objects to store the boxed parameter.
        mv.push(i);
        // Pushes the appropriate local variable on the stack
        mv.visitVarInsn(variable.type.getOpcode(Opcodes.ILOAD), variable.var);
        // potentially box up intrinsic types.
        mv.box(variable.type);
        // store it in the array
        mv.arrayStore(Type.getType(Object.class));
    }
}
 

/**
 * Given an array on the stack, it loads it with the values of the given variables stating at
 * offset.
 */
static void loadVariableArray(
         GeneratorAdapter mv,
         List<LocalVariable> variables, int offset) {
    // we need to maintain the stack index when loading parameters from, as for long and double
    // values, it uses 2 stack elements, all others use only 1 stack element.
    for (int i = offset; i < variables.size(); i++) {
        LocalVariable variable = variables.get(i);
        // duplicate the array of objects reference, it will be used to store the value in.
        mv.dup();
        // index in the array of objects to store the boxed parameter.
        mv.push(i);
        // Pushes the appropriate local variable on the stack
        mv.visitVarInsn(variable.type.getOpcode(Opcodes.ILOAD), variable.var);
        // potentially box up intrinsic types.
        mv.box(variable.type);
        // store it in the array
        mv.arrayStore(Type.getType(Object.class));
    }
}
 

/**
 * Adds the instructions to do a generic redirection.
 * <p/>
 * Note that the generated bytecode does not have a direct translation to code, but as an
 * example, the following code block gets inserted.
 * <code>
 * if ($change != null) {
 * $change.access$dispatch($name, new object[] { arg0, ... argsN })
 * $anyCodeInsertedbyRestore
 * }
 * $originalMethodBody
 * </code>
 *
 * @param mv     the method visitor to add the instructions to.
 * @param change the local variable containing the alternate implementation.
 * @param args   the type of the local variable that need to be forwarded.
 */
void redirect(GeneratorAdapter mv, int change, List<Type> args) {
    // code to check if a new implementation of the current class is available.
    Label l0 = new Label();
    mv.loadLocal(change);
    mv.visitJumpInsn(Opcodes.IFNULL, l0);
    mv.loadLocal(change);
    mv.push(name);

    // create an array of objects capable of containing all the parameters and optionally the "this"
    createLocals(mv, args);

    // we need to maintain the stack index when loading parameters from, as for long and double
    // values, it uses 2 stack elements, all others use only 1 stack element.
    int stackIndex = 0;
    for (int arrayIndex = 0; arrayIndex < args.size(); arrayIndex++) {
        Type arg = args.get(arrayIndex);
        // duplicate the array of objects reference, it will be used to store the value in.
        mv.dup();
        // index in the array of objects to store the boxed parameter.
        mv.push(arrayIndex);
        // Pushes the appropriate local variable on the stack
        redirectLocal(mv, stackIndex, arg);
        // potentially box up intrinsic types.
        mv.box(arg);
        mv.arrayStore(Type.getType(Object.class));
        // stack index must progress according to the parameter type we just processed.
        stackIndex += arg.getSize();
    }

    // now invoke the generic dispatch method.
    mv.invokeInterface(IncrementalVisitor.CHANGE_TYPE, Method.getMethod("Object access$dispatch(String, Object[])"));

    // Restore the state after the redirection
    restore(mv, args);
    // jump label for classes without any new implementation, just invoke the original
    // method implementation.
    mv.visitLabel(l0);
}
 

private static void generateRun(ClassVisitor cv, Type testType, int iThread, List<Actor> actors, List<Object> objArgs, boolean waitsEnabled) {
    int access = ACC_PUBLIC;
    Method m = new Method("call", RESULT_ARRAY_TYPE, NO_ARGS);
    GeneratorAdapter mv = new GeneratorAdapter(access, m,
        // Try-catch blocks sorting is required
        new TryCatchBlockSorter(cv.visitMethod(access, m.getName(), m.getDescriptor(), null, null),
            access, m.getName(), m.getDescriptor(), null, null)
    );
    mv.visitCode();
    // Create Result[] array and store it to a local variable
    int resLocal = createResultArray(mv, actors.size());
    // Call runner's onStart(iThread) method
    mv.loadThis();
    mv.getField(TEST_THREAD_EXECUTION_TYPE, "runner", RUNNER_TYPE);
    mv.push(iThread);
    mv.invokeVirtual(RUNNER_TYPE, RUNNER_ON_START_METHOD);
    // Number of current operation (starts with 0)
    int iLocal = mv.newLocal(Type.INT_TYPE);
    mv.push(0);
    mv.storeLocal(iLocal);
    // Invoke actors
    for (int i = 0; i < actors.size(); i++) {
        Actor actor = actors.get(i);
        // Add busy-wait before operation execution (for non-first operations only)
        if (waitsEnabled && i > 0) {
            mv.loadThis();
            mv.getField(TEST_THREAD_EXECUTION_TYPE, "waits", INT_ARRAY_TYPE);
            mv.push(i - 1);
            mv.arrayLoad(Type.INT_TYPE);
            mv.invokeStatic(UTILS_TYPE, UTILS_CONSUME_CPU);
        }
        // Start of try-catch block for exceptions which this actor should handle
        Label start, end = null, handler = null, handlerEnd = null;
        if (actor.handlesExceptions()) {
            start = mv.newLabel();
            end = mv.newLabel();
            handler = mv.newLabel();
            handlerEnd = mv.newLabel();
            for (Class<? extends Throwable> ec : actor.handledExceptions)
                mv.visitTryCatchBlock(start, end, handler, Type.getType(ec).getInternalName());
            mv.visitLabel(start);
        }
        // Load result array and index to store the current result
        mv.loadLocal(resLocal);
        mv.push(i);
        // Load test instance
        mv.loadThis();
        mv.getField(TEST_THREAD_EXECUTION_TYPE, "testInstance", OBJECT_TYPE);
        mv.checkCast(testType);
        // Load arguments for operation
        for (int j = 0; j < actor.arguments.length; j++) {
            pushArgumentOnStack(mv, objArgs, actor.arguments[j], actor.method.getParameterTypes()[j]);
        }
        // Invoke operation
        Method actorMethod = Method.getMethod(actor.method);
        mv.invokeVirtual(testType, actorMethod);
        // Create result
        mv.box(actorMethod.getReturnType()); // box if needed
        if (actor.method.getReturnType() == void.class) {
            mv.pop();
            mv.invokeStatic(RESULT_TYPE, RESULT_CREATE_VOID_RESULT);
        } else {
            mv.invokeStatic(RESULT_TYPE, RESULT_CREATE_VALUE_RESULT);
        }
        // Store result to array
        mv.arrayStore(RESULT_TYPE);
        // End of try-catch block
        if (actor.handlesExceptions()) {
            mv.visitLabel(end);
            mv.goTo(handlerEnd);
            mv.visitLabel(handler);
            storeExceptionResultFromThrowable(mv, resLocal, iLocal);
            mv.visitLabel(handlerEnd);
        }
        // Increment number of current operation
        mv.iinc(iLocal, 1);
    }
    // Call runner's onFinish(iThread) method
    mv.loadThis();
    mv.getField(TEST_THREAD_EXECUTION_TYPE, "runner", RUNNER_TYPE);
    mv.push(iThread);
    mv.invokeVirtual(RUNNER_TYPE, RUNNER_ON_FINISH_METHOD);
    // Return results
    mv.loadThis();
    mv.loadLocal(resLocal);
    mv.returnValue();
    mv.visitMaxs(1, 1);
    mv.visitEnd();
}