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

/**
 * 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 ($starkChange != null) {
 *   $starkChange.access$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.
 */
void redirect(GeneratorAdapter mv, int change) {
    // 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);

    doRedirect(mv, change);

    // Return
    if (type == Type.VOID_TYPE) {
        mv.pop();
    } else {
        ByteCodeUtils.unbox(mv, type);
    }
    mv.returnValue();

    // jump label for classes without any new implementation, just invoke the original
    // method implementation.
    mv.visitLabel(l0);
}
 

/**
 * Adds the instructions to do a generic redirection.
 */
protected void redirect(GeneratorAdapter mv, int change) {
    // 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);
    doRedirect(mv, change);

    // Return
    if (type == Type.VOID_TYPE) {
        mv.pop();
    } else {
        ByteCodeUtils.unbox(mv, type);
    }
    mv.returnValue();

    // jump label for classes without any new implementation, just invoke the original
    // method implementation.
    mv.visitLabel(l0);
}
 

@Override
protected void doRedirect(@NonNull GeneratorAdapter mv, int change) {
    // Push the three arguments
    mv.loadLocal(change);
    mv.push(name);
    ByteCodeUtils.newVariableArray(mv, ByteCodeUtils.toLocalVariables(types));

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

@Override
protected void doRedirect(GeneratorAdapter mv, int change) {
    // Push the three arguments
    mv.loadLocal(change);
    mv.push(name);
    ByteCodeUtils.newVariableArray(mv, ByteCodeUtils.toLocalVariables(types));

    // now invoke the generic dispatch method.
    mv.invokeInterface(TBIncrementalSupportVisitor.ALI_CHANGE_TYPE, Method.getMethod("Object ipc$dispatch(String, Object[])"));
}
 

@Override
protected void doRedirect( GeneratorAdapter mv, int change) {
    mv.loadLocal(change);
    mv.push(AcesoProguardMap.instance().getMtdIndex(visitedClassName, IncrementalTool.getMtdSig(mtdName,mtdDesc)));
    ByteCodeUtils.newVariableArray(mv, ByteCodeUtils.toLocalVariables(types));

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

/**
 * 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);
}
 

@Override
protected void redirectLocal(GeneratorAdapter mv, int stackIndex, Type arg) {
    // If the stack index is 0, we do not send the local variable 0 (this) as it
    // cannot escape the constructor. Instead, we use this argument position to send
    // a reference to the locals array where the redirected method will return their
    // values.
    if (stackIndex == 0) {
        mv.loadLocal(locals);
    } else {
        super.redirectLocal(mv, stackIndex, arg);
    }
}
 

private static void storeExceptionResultFromThrowable(GeneratorAdapter mv, int resLocal, int iLocal) {
    int eLocal = mv.newLocal(THROWABLE_TYPE);
    mv.storeLocal(eLocal);
    mv.loadLocal(resLocal);
    mv.loadLocal(iLocal);
    mv.loadLocal(eLocal);
    mv.invokeVirtual(OBJECT_TYPE, OBJECT_GET_CLASS);
    mv.invokeStatic(RESULT_TYPE, RESULT_CREATE_EXCEPTION_RESULT);
    mv.arrayStore(RESULT_TYPE);
}
 

@Override
public Type load(Context ctx) {
	GeneratorAdapter g = ctx.getGeneratorAdapter();
	Type leftType = left.load(ctx);
	if (isWrapperType(leftType)) {
		leftType = unwrap(leftType);
		g.unbox(leftType);
	}
	Type rightType = right.load(ctx);
	if (isWrapperType(rightType)) {
		rightType = unwrap(rightType);
		g.unbox(rightType);
	}
	if (op != SHL && op != SHR && op != USHR) {
		Type resultType = getType(unifyArithmeticTypes(ctx.toJavaType(leftType), ctx.toJavaType(rightType)));
		if (leftType != resultType) {
			int rightLocal = g.newLocal(rightType);
			g.storeLocal(rightLocal);
			g.cast(leftType, resultType);
			g.loadLocal(rightLocal);
		}
		if (rightType != resultType) {
			g.cast(rightType, resultType);
		}
		g.visitInsn(resultType.getOpcode(op.opCode));
		return resultType;
	} else {
		if (rightType != Type.getType(int.class)) {
			g.cast(rightType, Type.getType(int.class));
		}
		g.visitInsn(leftType.getOpcode(op.opCode));
		return leftType;
	}
}
 

@Override
protected void doRedirect(GeneratorAdapter mv, int change) {
    mv.loadLocal(change);
    mv.push("init$args." + constructor.args.desc);

    Type arrayType = Type.getType("[Ljava/lang/Object;");
    // init$args args (including this) + locals
    mv.push(types.size() + 1);
    mv.newArray(Type.getType(Object.class));

    int array = mv.newLocal(arrayType);
    mv.dup();
    mv.storeLocal(array);

    // "this" is not ready yet, use null instead.
    mv.dup();
    mv.push(0);
    mv.visitInsn(Opcodes.ACONST_NULL);
    mv.arrayStore(Type.getType(Object.class));

    // Set the arguments in positions 1..(n-1);
    ByteCodeUtils.loadVariableArray(mv, ByteCodeUtils.toLocalVariables(types), 1); // Skip the this value

    // Add the locals array at the last position.
    mv.dup();
    // The index of the last position of the array.
    mv.push(types.size());
    // Create the array with all the local variables declared up to this point.
    ByteCodeUtils.newVariableArray(mv, constructor.variables.subList(0, constructor.localsAtLoadThis));
    mv.arrayStore(Type.getType(Object.class));

    mv.invokeInterface(MonitorVisitor.CHANGE_TYPE, Method.getMethod("Object access$dispatch(String, Object[])"));
    mv.visitTypeInsn(Opcodes.CHECKCAST, "[Ljava/lang/Object;");
    //// At this point, init$args has been called and the result Object is on the stack.
    //// The value of that Object is Object[] with exactly n + 2 elements.
    //// The first element is the resulting local variables
    //// The second element is a string with the qualified name of the constructor to call.
    //// The remaining elements are the constructor arguments.

    // Keep a reference to the new locals array
    mv.dup();
    mv.push(0);
    mv.arrayLoad(Type.getType("[Ljava/lang/Object;"));
    mv.visitTypeInsn(Opcodes.CHECKCAST, "[Ljava/lang/Object;");
    mv.storeLocal(array);

    // Call super constructor
    // Put this behind the returned array
    mv.visitVarInsn(Opcodes.ALOAD, 0);
    mv.swap();
    // Push a null for the marker parameter.
    mv.visitInsn(Opcodes.ACONST_NULL);
    // Invoke the constructor
    mv.visitMethodInsn(Opcodes.INVOKESPECIAL, constructor.owner, "<init>", DISPATCHING_THIS_SIGNATURE, false);

    // Dispatch to init$body
    mv.loadLocal(change);
    mv.push("init$body." + constructor.body.desc);
    mv.loadLocal(array);

    // Now "this" can be set
    mv.dup();
    mv.push(0);
    mv.visitVarInsn(Opcodes.ALOAD, 0);
    mv.arrayStore(Type.getType(Object.class));

    mv.invokeInterface(MonitorVisitor.CHANGE_TYPE, Method.getMethod("Object access$dispatch(String, Object[])"));
    mv.pop();
}
 

@Override
protected void doRedirect(GeneratorAdapter mv, int change) {
    mv.loadLocal(change);
    mv.push("init$args." + constructor.args.desc);

    Type arrayType = Type.getType("[Ljava/lang/Object;");
    // init$args args (including this) + locals
    mv.push(types.size() + 1);
    mv.newArray(Type.getType(Object.class));

    int array = mv.newLocal(arrayType);
    mv.dup();
    mv.storeLocal(array);

    // "this" is not ready yet, use null instead.
    mv.dup();
    mv.push(0);
    mv.visitInsn(Opcodes.ACONST_NULL);
    mv.arrayStore(Type.getType(Object.class));

    // Set the arguments in positions 1..(n-1);
    ByteCodeUtils.loadVariableArray(mv, ByteCodeUtils.toLocalVariables(types), 1); // Skip the this value

    // Add the locals array at the last position.
    mv.dup();
    // The index of the last position of the array.
    mv.push(types.size());
    // Create the array with all the local variables declared up to this point.
    ByteCodeUtils.newVariableArray(mv, constructor.variables.subList(0, constructor.localsAtLoadThis));
    mv.arrayStore(Type.getType(Object.class));

    mv.invokeInterface(TBIncrementalVisitor.ALI_CHANGE_TYPE, Method.getMethod("Object ipc$dispatch(String, Object[])"));
    mv.visitTypeInsn(Opcodes.CHECKCAST, "[Ljava/lang/Object;");
    //// At this point, init$args has been called and the result Object is on the stack.
    //// The value of that Object is Object[] with exactly n + 2 elements.
    //// The first element is the resulting local variables
    //// The second element is a string with the qualified name of the constructor to call.
    //// The remaining elements are the constructor arguments.

    // Keep a reference to the new locals array
    mv.dup();
    mv.push(0);
    mv.arrayLoad(Type.getType("[Ljava/lang/Object;"));
    mv.visitTypeInsn(Opcodes.CHECKCAST, "[Ljava/lang/Object;");
    mv.storeLocal(array);

    // Call super constructor
    // Put this behind the returned array
    mv.visitVarInsn(Opcodes.ALOAD, 0);
    mv.swap();
    // Push a null for the marker parameter.
    mv.visitInsn(Opcodes.ACONST_NULL);
    // Invoke the constructor
    mv.visitMethodInsn(Opcodes.INVOKESPECIAL, constructor.owner, "<init>", DISPATCHING_THIS_SIGNATURE, false);

    // Dispatch to init$body
    mv.loadLocal(change);
    mv.push("init$body." + constructor.body.desc);
    mv.loadLocal(array);

    // Now "this" can be set
    mv.dup();
    mv.push(0);
    mv.visitVarInsn(Opcodes.ALOAD, 0);
    mv.arrayStore(Type.getType(Object.class));

    mv.invokeInterface(TBIncrementalVisitor.ALI_CHANGE_TYPE, Method.getMethod("Object ipc$dispatch(String, Object[])"));
    mv.pop();
}
 

/**
 * 插入代码
 *
 * @param mv
 * @param className
 * @param args
 * @param returnType
 * @param isStatic
 */
public static void createInsertCode(GeneratorAdapter mv, String className, List<Type> args, Type returnType, boolean isStatic, int methodId) {
    prepareMethodParameters(mv, className, args, returnType, isStatic, methodId);
    //开始调用
    mv.visitMethodInsn(Opcodes.INVOKESTATIC,
            PROXYCLASSNAME,
            "proxy",
            "([Ljava/lang/Object;Ljava/lang/Object;" + REDIRECTCLASSNAME + "ZI[Ljava/lang/Class;Ljava/lang/Class;)Lcom/meituan/robust/PatchProxyResult;",
            false);

    int local = mv.newLocal(Type.getType("Lcom/meituan/robust/PatchProxyResult;"));
    mv.storeLocal(local);
    mv.loadLocal(local);

    mv.visitFieldInsn(Opcodes.GETFIELD, "com/meituan/robust/PatchProxyResult", "isSupported", "Z");

    // if isSupported
    Label l1 = new Label();
    mv.visitJumpInsn(Opcodes.IFEQ, l1);

    //判断是否有返回值，代码不同
    if ("V".equals(returnType.getDescriptor())) {
        mv.visitInsn(Opcodes.RETURN);
    } else {
        mv.loadLocal(local);
        mv.visitFieldInsn(Opcodes.GETFIELD, "com/meituan/robust/PatchProxyResult", "result", "Ljava/lang/Object;");
        //强制转化类型
        if (!castPrimateToObj(mv, returnType.getDescriptor())) {
            //这里需要注意，如果是数组类型的直接使用即可，如果非数组类型，就得去除前缀了,还有最终是没有结束符;
            //比如：Ljava/lang/String; ==》 java/lang/String
            String newTypeStr = null;
            int len = returnType.getDescriptor().length();
            if (returnType.getDescriptor().startsWith("[")) {
                newTypeStr = returnType.getDescriptor().substring(0, len);
            } else {
                newTypeStr = returnType.getDescriptor().substring(1, len - 1);
            }
            mv.visitTypeInsn(Opcodes.CHECKCAST, newTypeStr);
        }

        //这里还需要做返回类型不同返回指令也不同
        mv.visitInsn(getReturnTypeCode(returnType.getDescriptor()));
    }

    mv.visitLabel(l1);
}
 

@Override
protected void restore(GeneratorAdapter mv, List<Type> args) {
    // At this point, init$args has been called and the result Object is on the stack.
    // The value of that Object is Object[] with exactly n + 1 elements.
    // The first element is a string with the qualified name of the constructor to call.
    // The remaining elements are the constructtor arguments.

    // Create a new local that holds the result of init$args call.
    mv.visitTypeInsn(Opcodes.CHECKCAST, "[Ljava/lang/Object;");
    int constructorArgs = mv.newLocal(Type.getType("[Ljava/lang/Object;"));
    mv.storeLocal(constructorArgs);

    // Reinstate local values
    mv.loadLocal(locals);
    int stackIndex = 0;
    for (int arrayIndex = 0; arrayIndex < args.size(); arrayIndex++) {
        Type arg = args.get(arrayIndex);
        // Do not restore "this"
        if (arrayIndex > 0) {
            // duplicates the array
            mv.dup();
            // index in the array of objects to restore the boxed parameter.
            mv.push(arrayIndex);
            // get it from the array
            mv.arrayLoad(Type.getType(Object.class));
            // unbox the argument
            ByteCodeUtils.unbox(mv, arg);
            // restore the argument
            mv.visitVarInsn(arg.getOpcode(Opcodes.ISTORE), stackIndex);
        }
        // stack index must progress according to the parameter type we just processed.
        stackIndex += arg.getSize();
    }
    // pops the array
    mv.pop();

    // Push a null for the marker parameter.
    mv.loadLocal(constructorArgs);
    mv.visitInsn(Opcodes.ACONST_NULL);

    // Invoke the constructor
    mv.visitMethodInsn(Opcodes.INVOKESPECIAL, thisClassName, "<init>", DISPATCHING_THIS_SIGNATURE, false);

    mv.goTo(end.getLabel());
}
 

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();
}
 

@Override
public Type load(Context ctx) {
	GeneratorAdapter g = ctx.getGeneratorAdapter();

	int resultVar = g.newLocal(INT_TYPE);

	boolean firstIteration = true;

	for (Expression argument : arguments) {
		if (firstIteration) {
			g.push(0);
			firstIteration = false;
		} else {
			g.push(31);
			g.loadLocal(resultVar);
			g.math(IMUL, INT_TYPE);
		}

		Type fieldType = argument.load(ctx);

		if (isPrimitiveType(fieldType)) {
			if (fieldType.getSort() == Type.LONG) {
				g.dup2();
				g.push(32);
				g.visitInsn(LUSHR);
				g.visitInsn(LXOR);
				g.visitInsn(L2I);
			}
			if (fieldType.getSort() == Type.FLOAT) {
				g.invokeStatic(getType(Float.class), getMethod("int floatToRawIntBits (float)"));
			}
			if (fieldType.getSort() == Type.DOUBLE) {
				g.invokeStatic(getType(Double.class), getMethod("long doubleToRawLongBits (double)"));
				g.dup2();
				g.push(32);
				g.visitInsn(LUSHR);
				g.visitInsn(LXOR);
				g.visitInsn(L2I);
			}
			g.visitInsn(IADD);
		} else {
			int tmpVar = g.newLocal(fieldType);
			g.storeLocal(tmpVar);
			g.loadLocal(tmpVar);
			Label ifNullLabel = g.newLabel();
			g.ifNull(ifNullLabel);
			g.loadLocal(tmpVar);
			g.invokeVirtual(fieldType, getMethod("int hashCode()"));
			g.visitInsn(IADD);
			g.mark(ifNullLabel);
		}

		g.storeLocal(resultVar);
	}

	if (firstIteration) {
		g.push(0);
	} else {
		g.loadLocal(resultVar);
	}

	return INT_TYPE;
}
 

@Override
public Type load(Context ctx) {
	GeneratorAdapter g = ctx.getGeneratorAdapter();
	g.loadLocal(local);
	return g.getLocalType(local);
}