/*
* Copyright (c) 2001, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.sun.tools.javac.jvm;
import java.util.*;
import com.sun.tools.javac.tree.*;
import com.sun.tools.javac.util.*;
import com.sun.tools.javac.util.List;
import com.sun.tools.javac.tree.JCTree.*;
/** This class contains the CharacterRangeTable for some method
* and the hashtable for mapping trees or lists of trees to their
* ending positions.
*
* <p><b>This is NOT part of any supported API.
* If you write code that depends on this, you do so at your own risk.
* This code and its internal interfaces are subject to change or
* deletion without notice.</b>
*/
public class CRTable
implements CRTFlags {
private final boolean crtDebug = false;
/** The list of CRTable entries.
*/
private ListBuffer<CRTEntry> entries = new ListBuffer<CRTEntry>();
/** The hashtable for source positions.
*/
private Map<Object,SourceRange> positions = new HashMap<Object,SourceRange>();
/** The hashtable for ending positions stored in the parser.
*/
private Map<JCTree, Integer> endPositions;
/** The tree of the method this table is intended for.
* We should traverse this tree to get source ranges.
*/
JCTree.JCMethodDecl methodTree;
/** Constructor
*/
public CRTable(JCTree.JCMethodDecl tree, Map<JCTree, Integer> endPositions) {
this.methodTree = tree;
this.endPositions = endPositions;
}
/** Create a new CRTEntry and add it to the entries.
* @param tree The tree or the list of trees for which
* we are storing the code pointers.
* @param flags The set of flags designating type of the entry.
* @param startPc The starting code position.
* @param endPc The ending code position.
*/
public void put(Object tree, int flags, int startPc, int endPc) {
entries.append(new CRTEntry(tree, flags, startPc, endPc));
}
/** Compute source positions and write CRT to the databuf.
* @param databuf The buffer to write bytecodes to.
*/
public int writeCRT(ByteBuffer databuf, Position.LineMap lineMap, Log log) {
int crtEntries = 0;
// compute source positions for the method
new SourceComputer().csp(methodTree);
for (List<CRTEntry> l = entries.toList(); l.nonEmpty(); l = l.tail) {
CRTEntry entry = l.head;
// eliminate entries that do not produce bytecodes:
// for example, empty blocks and statements
if (entry.startPc == entry.endPc)
continue;
SourceRange pos = positions.get(entry.tree);
Assert.checkNonNull(pos, "CRT: tree source positions are undefined");
if ((pos.startPos == Position.NOPOS) || (pos.endPos == Position.NOPOS))
continue;
if (crtDebug) {
System.out.println("Tree: " + entry.tree + ", type:" + getTypes(entry.flags));
System.out.print("Start: pos = " + pos.startPos + ", pc = " + entry.startPc);
}
// encode startPos into line/column representation
int startPos = encodePosition(pos.startPos, lineMap, log);
if (startPos == Position.NOPOS)
continue;
if (crtDebug) {
System.out.print("End: pos = " + pos.endPos + ", pc = " + (entry.endPc - 1));
}
// encode endPos into line/column representation
int endPos = encodePosition(pos.endPos, lineMap, log);
if (endPos == Position.NOPOS)
continue;
// write attribute
databuf.appendChar(entry.startPc);
// 'endPc - 1' because endPc actually points to start of the next command
databuf.appendChar(entry.endPc - 1);
databuf.appendInt(startPos);
databuf.appendInt(endPos);
databuf.appendChar(entry.flags);
crtEntries++;
}
return crtEntries;
}
/** Return the number of the entries.
*/
public int length() {
return entries.length();
}
/** Return string describing flags enabled.
*/
private String getTypes(int flags) {
String types = "";
if ((flags & CRT_STATEMENT) != 0) types += " CRT_STATEMENT";
if ((flags & CRT_BLOCK) != 0) types += " CRT_BLOCK";
if ((flags & CRT_ASSIGNMENT) != 0) types += " CRT_ASSIGNMENT";
if ((flags & CRT_FLOW_CONTROLLER) != 0) types += " CRT_FLOW_CONTROLLER";
if ((flags & CRT_FLOW_TARGET) != 0) types += " CRT_FLOW_TARGET";
if ((flags & CRT_INVOKE) != 0) types += " CRT_INVOKE";
if ((flags & CRT_CREATE) != 0) types += " CRT_CREATE";
if ((flags & CRT_BRANCH_TRUE) != 0) types += " CRT_BRANCH_TRUE";
if ((flags & CRT_BRANCH_FALSE) != 0) types += " CRT_BRANCH_FALSE";
return types;
}
/** Source file positions in CRT are integers in the format:
* line-number << LINESHIFT + column-number
*/
private int encodePosition(int pos, Position.LineMap lineMap, Log log) {
int line = lineMap.getLineNumber(pos);
int col = lineMap.getColumnNumber(pos);
int new_pos = Position.encodePosition(line, col);
if (crtDebug) {
System.out.println(", line = " + line + ", column = " + col +
", new_pos = " + new_pos);
}
if (new_pos == Position.NOPOS)
log.warning(pos, "position.overflow", line);
return new_pos;
}
/* ************************************************************************
* Traversal methods
*************************************************************************/
/**
* This class contains methods to compute source positions for trees.
* Extends Tree.Visitor to traverse the abstract syntax tree.
*/
class SourceComputer extends JCTree.Visitor {
/** The result of the tree traversal methods.
*/
SourceRange result;
/** Visitor method: compute source positions for a single node.
*/
public SourceRange csp(JCTree tree) {
if (tree == null) return null;
tree.accept(this);
if (result != null) {
positions.put(tree, result);
}
return result;
}
/** Visitor method: compute source positions for a list of nodes.
*/
public SourceRange csp(List<? extends JCTree> trees) {
if ((trees == null) || !(trees.nonEmpty())) return null;
SourceRange list_sr = new SourceRange();
for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) {
list_sr.mergeWith(csp(l.head));
}
positions.put(trees, list_sr);
return list_sr;
}
/** Visitor method: compute source positions for
* a list of case blocks of switch statements.
*/
public SourceRange cspCases(List<JCCase> trees) {
if ((trees == null) || !(trees.nonEmpty())) return null;
SourceRange list_sr = new SourceRange();
for (List<JCCase> l = trees; l.nonEmpty(); l = l.tail) {
list_sr.mergeWith(csp(l.head));
}
positions.put(trees, list_sr);
return list_sr;
}
/** Visitor method: compute source positions for
* a list of catch clauses in try statements.
*/
public SourceRange cspCatchers(List<JCCatch> trees) {
if ((trees == null) || !(trees.nonEmpty())) return null;
SourceRange list_sr = new SourceRange();
for (List<JCCatch> l = trees; l.nonEmpty(); l = l.tail) {
list_sr.mergeWith(csp(l.head));
}
positions.put(trees, list_sr);
return list_sr;
}
public void visitMethodDef(JCMethodDecl tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.body));
result = sr;
}
public void visitVarDef(JCVariableDecl tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
csp(tree.vartype);
sr.mergeWith(csp(tree.init));
result = sr;
}
public void visitSkip(JCSkip tree) {
// endPos is the same as startPos for the empty statement
SourceRange sr = new SourceRange(startPos(tree), startPos(tree));
result = sr;
}
public void visitBlock(JCBlock tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
csp(tree.stats); // doesn't compare because block's ending position is defined
result = sr;
}
public void visitDoLoop(JCDoWhileLoop tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.body));
sr.mergeWith(csp(tree.cond));
result = sr;
}
public void visitWhileLoop(JCWhileLoop tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.cond));
sr.mergeWith(csp(tree.body));
result = sr;
}
public void visitForLoop(JCForLoop tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.init));
sr.mergeWith(csp(tree.cond));
sr.mergeWith(csp(tree.step));
sr.mergeWith(csp(tree.body));
result = sr;
}
public void visitForeachLoop(JCEnhancedForLoop tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.var));
sr.mergeWith(csp(tree.expr));
sr.mergeWith(csp(tree.body));
result = sr;
}
public void visitLabelled(JCLabeledStatement tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.body));
result = sr;
}
public void visitSwitch(JCSwitch tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.selector));
sr.mergeWith(cspCases(tree.cases));
result = sr;
}
public void visitCase(JCCase tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.pat));
sr.mergeWith(csp(tree.stats));
result = sr;
}
public void visitSynchronized(JCSynchronized tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.lock));
sr.mergeWith(csp(tree.body));
result = sr;
}
public void visitTry(JCTry tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.resources));
sr.mergeWith(csp(tree.body));
sr.mergeWith(cspCatchers(tree.catchers));
sr.mergeWith(csp(tree.finalizer));
result = sr;
}
public void visitCatch(JCCatch tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.param));
sr.mergeWith(csp(tree.body));
result = sr;
}
public void visitConditional(JCConditional tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.cond));
sr.mergeWith(csp(tree.truepart));
sr.mergeWith(csp(tree.falsepart));
result = sr;
}
public void visitIf(JCIf tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.cond));
sr.mergeWith(csp(tree.thenpart));
sr.mergeWith(csp(tree.elsepart));
result = sr;
}
public void visitExec(JCExpressionStatement tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.expr));
result = sr;
}
public void visitBreak(JCBreak tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
result = sr;
}
public void visitContinue(JCContinue tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
result = sr;
}
public void visitReturn(JCReturn tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.expr));
result = sr;
}
public void visitThrow(JCThrow tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.expr));
result = sr;
}
public void visitAssert(JCAssert tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.cond));
sr.mergeWith(csp(tree.detail));
result = sr;
}
public void visitApply(JCMethodInvocation tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.meth));
sr.mergeWith(csp(tree.args));
result = sr;
}
public void visitNewClass(JCNewClass tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.encl));
sr.mergeWith(csp(tree.clazz));
sr.mergeWith(csp(tree.args));
sr.mergeWith(csp(tree.def));
result = sr;
}
public void visitNewArray(JCNewArray tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.elemtype));
sr.mergeWith(csp(tree.dims));
sr.mergeWith(csp(tree.elems));
result = sr;
}
public void visitParens(JCParens tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.expr));
result = sr;
}
public void visitAssign(JCAssign tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.lhs));
sr.mergeWith(csp(tree.rhs));
result = sr;
}
public void visitAssignop(JCAssignOp tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.lhs));
sr.mergeWith(csp(tree.rhs));
result = sr;
}
public void visitUnary(JCUnary tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.arg));
result = sr;
}
public void visitBinary(JCBinary tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.lhs));
sr.mergeWith(csp(tree.rhs));
result = sr;
}
public void visitTypeCast(JCTypeCast tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.clazz));
sr.mergeWith(csp(tree.expr));
result = sr;
}
public void visitTypeTest(JCInstanceOf tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.expr));
sr.mergeWith(csp(tree.clazz));
result = sr;
}
public void visitIndexed(JCArrayAccess tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.indexed));
sr.mergeWith(csp(tree.index));
result = sr;
}
public void visitSelect(JCFieldAccess tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.selected));
result = sr;
}
public void visitIdent(JCIdent tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
result = sr;
}
public void visitLiteral(JCLiteral tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
result = sr;
}
public void visitTypeIdent(JCPrimitiveTypeTree tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
result = sr;
}
public void visitTypeArray(JCArrayTypeTree tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.elemtype));
result = sr;
}
public void visitTypeApply(JCTypeApply tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.clazz));
sr.mergeWith(csp(tree.arguments));
result = sr;
}
public void visitTypeParameter(JCTypeParameter tree) {
SourceRange sr = new SourceRange(startPos(tree), endPos(tree));
sr.mergeWith(csp(tree.bounds));
result = sr;
}
public void visitWildcard(JCWildcard tree) {
result = null;
}
public void visitErroneous(JCErroneous tree) {
result = null;
}
public void visitTree(JCTree tree) {
Assert.error();
}
/** The start position of given tree.
*/
public int startPos(JCTree tree) {
if (tree == null) return Position.NOPOS;
return tree.pos;
}
/** The end position of given tree, if it has
* defined endpos, NOPOS otherwise.
*/
public int endPos(JCTree tree) {
if (tree == null) return Position.NOPOS;
if (tree.getTag() == JCTree.BLOCK)
return ((JCBlock) tree).endpos;
Integer endpos = endPositions.get(tree);
if (endpos != null)
return endpos.intValue();
return Position.NOPOS;
}
}
/** This class contains a CharacterRangeTableEntry.
*/
static class CRTEntry {
/** A tree or a list of trees to obtain source positions.
*/
Object tree;
/** The flags described in the CharacterRangeTable spec.
*/
int flags;
/** The starting code position of this entry.
*/
int startPc;
/** The ending code position of this entry.
*/
int endPc;
/** Constructor */
CRTEntry(Object tree, int flags, int startPc, int endPc) {
this.tree = tree;
this.flags = flags;
this.startPc = startPc;
this.endPc = endPc;
}
}
/** This class contains source positions
* for some tree or list of trees.
*/
static class SourceRange {
/** The starting source position.
*/
int startPos;
/** The ending source position.
*/
int endPos;
/** Constructor */
SourceRange() {
startPos = Position.NOPOS;
endPos = Position.NOPOS;
}
/** Constructor */
SourceRange(int startPos, int endPos) {
this.startPos = startPos;
this.endPos = endPos;
}
/** Compare the starting and the ending positions
* of the source range and combines them assigning
* the widest range to this.
*/
SourceRange mergeWith(SourceRange sr) {
if (sr == null) return this;
if (startPos == Position.NOPOS)
startPos = sr.startPos;
else if (sr.startPos != Position.NOPOS)
startPos = (startPos < sr.startPos ? startPos : sr.startPos);
if (endPos == Position.NOPOS)
endPos = sr.endPos;
else if (sr.endPos != Position.NOPOS)
endPos = (endPos > sr.endPos ? endPos : sr.endPos);
return this;
}
}
}