org.apache.flink.api.java.sca.ModifiedASMFrame Maven / Gradle / Ivy
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* 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 org.apache.flink.api.java.sca;
import org.apache.flink.annotation.Internal;
import org.objectweb.asm.tree.AbstractInsnNode;
import org.objectweb.asm.tree.analysis.AnalyzerException;
import org.objectweb.asm.tree.analysis.Frame;
import org.objectweb.asm.tree.analysis.Interpreter;
import org.objectweb.asm.tree.analysis.Value;
import java.lang.reflect.Field;
import java.util.Arrays;
/**
* Modified version of ASMs Frame. It allows to perform different merge
* priorities and passes frame information to the Interpreter.
*/
@Internal
public class ModifiedASMFrame extends Frame {
public boolean mergePriority;
public ModifiedASMFrame(int nLocals, int nStack) {
super(nLocals, nStack);
}
public ModifiedASMFrame(Frame src) {
super(src);
}
@Override
public Frame init(Frame src) {
mergePriority = ((ModifiedASMFrame)src).mergePriority;
return super.init(src);
}
@Override
public void execute(AbstractInsnNode insn, Interpreter interpreter)
throws AnalyzerException {
NestedMethodAnalyzer nma = ((NestedMethodAnalyzer) interpreter);
nma.currentFrame = (ModifiedASMFrame) this;
super.execute(insn, interpreter);
}
@Override
public boolean merge(Frame frame, Interpreter interpreter) throws AnalyzerException {
if (((ModifiedASMFrame)frame).mergePriority) {
((NestedMethodAnalyzer)interpreter).rightMergePriority = true;
}
final boolean result = super.merge(frame, interpreter);
((NestedMethodAnalyzer)interpreter).rightMergePriority = false;
((ModifiedASMFrame)frame).mergePriority = false;
return result;
}
@Override
public String toString() {
// FOR DEBUGGING
try {
Class frame = Frame.class;
Field valuesField = frame.getDeclaredField("values");
valuesField.setAccessible(true);
Value[] newValues = (Value[]) valuesField.get(this);
return Arrays.toString(newValues);
}
catch (Exception e) {
throw new RuntimeException(e);
}
}
}