| /* |
| * reserved comment block |
| * DO NOT REMOVE OR ALTER! |
| */ |
| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.sun.org.apache.bcel.internal.generic; |
| |
| /** |
| * Super class for JSR - Jump to subroutine |
| * |
| */ |
| public abstract class JsrInstruction extends BranchInstruction implements UnconditionalBranch, |
| TypedInstruction, StackProducer { |
| |
| JsrInstruction(final short opcode, final InstructionHandle target) { |
| super(opcode, target); |
| } |
| |
| |
| /** |
| * Empty constructor needed for Instruction.readInstruction. |
| * Not to be used otherwise. |
| */ |
| JsrInstruction() { |
| } |
| |
| |
| /** @return return address type |
| */ |
| @Override |
| public Type getType( final ConstantPoolGen cp ) { |
| return new ReturnaddressType(physicalSuccessor()); |
| } |
| |
| |
| /** |
| * Returns an InstructionHandle to the physical successor |
| * of this JsrInstruction. <B>For this method to work, |
| * this JsrInstruction object must not be shared between |
| * multiple InstructionHandle objects!</B> |
| * Formally, there must not be InstructionHandle objects |
| * i, j where i != j and i.getInstruction() == this == |
| * j.getInstruction(). |
| * @return an InstructionHandle to the "next" instruction that |
| * will be executed when RETurned from a subroutine. |
| */ |
| public InstructionHandle physicalSuccessor() { |
| InstructionHandle ih = super.getTarget(); |
| // Rewind! |
| while (ih.getPrev() != null) { |
| ih = ih.getPrev(); |
| } |
| // Find the handle for "this" JsrInstruction object. |
| while (ih.getInstruction() != this) { |
| ih = ih.getNext(); |
| } |
| final InstructionHandle toThis = ih; |
| while (ih != null) { |
| ih = ih.getNext(); |
| if ((ih != null) && (ih.getInstruction() == this)) { |
| throw new RuntimeException("physicalSuccessor() called on a shared JsrInstruction."); |
| } |
| } |
| // Return the physical successor |
| return toThis.getNext(); |
| } |
| } |