org.apache.xalan.xsltc.compiler.util.OutlineableChunkStart Maven / Gradle / Ivy
/*
* 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.
*/
/*
* $Id$
*/
package org.apache.xalan.xsltc.compiler.util;
import org.apache.bcel.generic.Instruction;
/**
* This pseudo-instruction marks the beginning of a region of byte code that
* can be copied into a new method, termed an "outlineable" chunk. The size of
* the Java stack must be the same at the start of the region as it is at the
* end of the region, any value on the stack at the start of the region must not
* be consumed by an instruction in the region of code, the region must not
* contain a return instruction, no branch instruction in the region is
* permitted to have a target that is outside the region, and no branch
* instruction outside the region is permitted to have a target that is inside
* the region.
* The end of the region is marked by an {@link OutlineableChunkEnd}
* pseudo-instruction.
* Such a region of code may contain other outlineable regions.
*/
class OutlineableChunkStart extends MarkerInstruction {
/**
* A constant instance of {@link OutlineableChunkStart}. As it has no fields,
* there should be no need to create an instance of this class.
*/
public static final Instruction OUTLINEABLECHUNKSTART =
new OutlineableChunkStart();
/**
* Private default constructor. As it has no fields,
* there should be no need to create an instance of this class. See
* {@link OutlineableChunkStart#OUTLINEABLECHUNKSTART}.
*/
private OutlineableChunkStart() {
}
/**
* Get the name of this instruction. Used for debugging.
* @return the instruction name
*/
public String getName() {
return OutlineableChunkStart.class.getName();
}
/**
* Get the name of this instruction. Used for debugging.
* @return the instruction name
*/
public String toString() {
return getName();
}
/**
* Get the name of this instruction. Used for debugging.
* @return the instruction name
*/
public String toString(boolean verbose) {
return getName();
}
}