105 lines
3.4 KiB
Java
105 lines
3.4 KiB
Java
/*******************************************************************************
|
|
* Copyright (c) 2002,2006 IBM Corporation.
|
|
* All rights reserved. This program and the accompanying materials
|
|
* are made available under the terms of the Eclipse Public License v1.0
|
|
* which accompanies this distribution, and is available at
|
|
* http://www.eclipse.org/legal/epl-v10.html
|
|
*
|
|
* Contributors:
|
|
* IBM Corporation - initial API and implementation
|
|
*******************************************************************************/
|
|
package com.ibm.wala.shrikeCT;
|
|
|
|
/**
|
|
* This class reads LineNumberTable attributes.
|
|
*
|
|
* Instead of constructing a LineNumberTableReader directly, consider just calling LineNumberTableReader.makeBytecodeToSourceMap for
|
|
* convenient access to aggregate line number data from all the LineNumberTable attributes for a given Code.
|
|
*/
|
|
public final class LineNumberTableReader extends AttributeReader {
|
|
/**
|
|
* Build a reader for a LineNumberTable attribute.
|
|
*/
|
|
public LineNumberTableReader(ClassReader.AttrIterator iter) throws InvalidClassFileException {
|
|
super(iter, "LineNumberTable");
|
|
|
|
int offset = attr + 6;
|
|
checkSize(offset, 2);
|
|
int count = cr.getUShort(offset);
|
|
offset += 2;
|
|
checkSize(offset, count * 4);
|
|
}
|
|
|
|
/**
|
|
* @return the raw line number table data, a flattened sequence of (startPC, lineNumber) pairs
|
|
*/
|
|
public int[] getRawTable() {
|
|
int count = cr.getUShort(attr + 6);
|
|
int[] r = new int[count * 2];
|
|
int offset = attr + 8;
|
|
for (int i = 0; i < r.length; i++) {
|
|
r[i] = cr.getUShort(offset);
|
|
offset += 2;
|
|
}
|
|
return r;
|
|
}
|
|
|
|
/**
|
|
* Construct a "bytecode to source" map for the given code. This method aggregates all the LineNumberTable attributes for the code
|
|
* into one handy data structure.
|
|
*
|
|
* @return an array mapping each byte of the bytecode bytes to the line number that that byte belongs to, or null if there is no
|
|
* line number data in the Code
|
|
*/
|
|
public static int[] makeBytecodeToSourceMap(CodeReader code) throws InvalidClassFileException, IllegalArgumentException {
|
|
|
|
if (code == null) {
|
|
throw new IllegalArgumentException();
|
|
}
|
|
int[] r = null;
|
|
ClassReader cr = code.getClassReader();
|
|
|
|
ClassReader.AttrIterator iter = new ClassReader.AttrIterator();
|
|
code.initAttributeIterator(iter);
|
|
for (; iter.isValid(); iter.advance()) {
|
|
if (iter.getName().equals("LineNumberTable")) {
|
|
if (r == null) {
|
|
r = new int[code.getBytecodeLength()];
|
|
}
|
|
|
|
// check length
|
|
@SuppressWarnings("unused")
|
|
LineNumberTableReader lineNumberTableReader = new LineNumberTableReader(iter);
|
|
int attr = iter.getRawOffset();
|
|
int count = cr.getUShort(attr + 6);
|
|
int offset = attr + 8;
|
|
for (int j = 0; j < count; j++) {
|
|
int startPC = cr.getUShort(offset);
|
|
int lineNum = cr.getUShort(offset + 2);
|
|
offset += 4;
|
|
|
|
if (startPC < 0 || startPC >= r.length) {
|
|
throw new InvalidClassFileException(offset, "Invalid bytecode offset " + startPC + " in LineNumberTable");
|
|
}
|
|
r[startPC] = lineNum;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (r != null) {
|
|
// fill in gaps in the old line number map
|
|
int last = 0;
|
|
for (int i = 0; i < r.length; i++) {
|
|
int cur = r[i];
|
|
if (cur == 0) {
|
|
r[i] = last;
|
|
} else {
|
|
last = cur;
|
|
}
|
|
}
|
|
}
|
|
|
|
return r;
|
|
}
|
|
}
|