view src/share/vm/prims/jvmtiEnvFill.java @ 452:00b023ae2d78

6722113: CMS: Incorrect overflow handling during precleaning of Reference lists Summary: When we encounter marking stack overflow during precleaning of Reference lists, we were using the overflow list mechanism, which can cause problems on account of mutating the mark word of the header because of conflicts with mutator accesses and updates of that field. Instead we should use the usual mechanism for overflow handling in concurrent phases, namely dirtying of the card on which the overflowed object lies. Since precleaning effectively does a form of discovered list processing, albeit with discovery enabled, we needed to adjust some code to be correct in the face of interleaved processing and discovery. Reviewed-by: apetrusenko, jcoomes
author ysr
date Thu, 20 Nov 2008 12:27:41 -0800
parents a61af66fc99e
children c18cbe5936b8
line wrap: on
line source

/*
 * Copyright 2003-2005 Sun Microsystems, Inc.  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.
 *
 * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

import java.io.*;
import java.util.*;

class jvmtiEnvFill {

    public static void main(String[] args) throws IOException {
        if (args.length != 3) {
            System.err.println("usage: <filledFile> <stubFile> <resultFile>");
            System.exit(1);
        }
        String filledFN = args[0];
        String stubFN = args[1];
        String resultFN = args[2];

        SourceFile filledSF = new SourceFile(filledFN);
        SourceFile stubSF = new SourceFile(stubFN);


        stubSF.fill(filledSF);

        PrintWriter out = new PrintWriter(new FileWriter(resultFN));
        stubSF.output(out);
        out.close();
    }
}

class SourceFile {

    static final String endFilePrefix = "// end file prefix";
    static final String functionPrefix = "JvmtiEnv::";

    final String fn;
    LineNumberReader in;
    String line;
    List<String> top = new ArrayList<String>();
    List<String> before = new ArrayList<String>();
    boolean inFilePrefix = true;
    List<Function> functions = new ArrayList<Function>();
    Map<String, Function> functionMap = new HashMap<String, Function>();

    class Function {
      String name;
      String args;
      String compareArgs;
      List comment;
      List<String> body = new ArrayList<String>();

      Function() throws IOException {
        line = in.readLine();
        String trimmed = line.trim();
        if (!trimmed.startsWith(functionPrefix)) {
            error("expected '" + functionPrefix + "'");
        }
        int index = trimmed.indexOf('(', functionPrefix.length());
        if (index == -1) {
            error("missing open paren");
        }
        name = trimmed.substring(functionPrefix.length(), index);
        int index2 = trimmed.indexOf(')', index);
        if (index2 == -1) {
            error("missing close paren - must be on same line");
        }
        args = trimmed.substring(index+1, index2);
        compareArgs = args.replaceAll("\\s", "");
        String tail = trimmed.substring(index2+1).trim();
        if (!tail.equals("{")) {
            error("function declaration first line must end with open bracket '{', instead got '" +
                   tail + "'");
        }
        while(true) {
            line = in.readLine();
            if (line == null) {
                line = ""; // so error does not look wierd
                error("unexpected end of file");
            }
            if (line.startsWith("}")) {
                break;
            }
            body.add(line);
        }
        String expected = "} /* end " + name + " */";
        trimmed = line.replaceAll("\\s","");
        if (!trimmed.equals(expected.replaceAll("\\s",""))) {
            error("function end is malformed - should be: " + expected);
        }
        // copy over the comment prefix
        comment = before;
        before = new ArrayList<String>();
      }

      void remove() {
        functionMap.remove(name);
      }

      String fileName() {
        return fn;
      }

      void fill(Function filledFunc) {
        if (filledFunc == null) {
            System.err.println("Warning: function " + name + " missing from filled file");
            body.add(0, "    /*** warning: function added and not filled in ***/");
        } else {
            int fbsize = filledFunc.body.size();
            int bsize = body.size();
            if (fbsize > bsize  || !body.subList(bsize-fbsize,bsize).equals(filledFunc.body)) {
                // it has actually been filled in
                body = filledFunc.body;
                if (!compareArgs.equals(filledFunc.compareArgs)) {
                    System.err.println("Warning: function " + name +
                                       ": filled and stub arguments differ");
                    System.err.println("  old (filled): " + filledFunc.args);
                    System.err.println("  new (stub): " + args);
                    body.add(0, "    /*** warning: arguments changed, were: " +
                             filledFunc.args + " ***/");
                }
            }
            filledFunc.remove();  // mark used
        }
      }

      void output(PrintWriter out) {
            Iterator it = comment.iterator();
            while (it.hasNext()) {
                out.println(it.next());
            }
            out.println("jvmtiError");
            out.print(functionPrefix);
            out.print(name);
            out.print('(');
            out.print(args);
            out.println(") {");
            it = body.iterator();
            while (it.hasNext()) {
                out.println(it.next());
            }
            out.print("} /* end ");
            out.print(name);
            out.println(" */");
      }
    }

    SourceFile(String fn) throws IOException {
        this.fn = fn;
        Reader reader = new FileReader(fn);
        in = new LineNumberReader(reader);

        while (readGaps()) {
            Function func = new Function();
            functionMap.put(func.name, func);
            functions.add(func);
        }

        in.close();
    }

    void error(String msg) {
        System.err.println("Fatal error parsing file: " + fn);
        System.err.println("Line number: " + in.getLineNumber());
        System.err.println("Error message: " + msg);
        System.err.println("Source line: " + line);
        System.exit(1);
    }

    boolean readGaps() throws IOException {
        while(true) {
            line = in.readLine();
            if (line == null) {
                return false; // end of file
            }
            if (!inFilePrefix && line.startsWith("}")) {
                error("unexpected close bracket in first column, outside of function.\n");
            }
            String trimmed = line.trim();
            if (line.startsWith("jvmtiError")) {
                if (trimmed.equals("jvmtiError")) {
                    if (inFilePrefix) {
                        error("unexpected 'jvmtiError' line in file prefix.\n" +
                              "is '" + endFilePrefix + "'... line missing?");
                    }
                    return true; // beginning of a function
                } else {
                    error("extra characters at end of 'jvmtiError'");
                }
            }
            if (inFilePrefix) {
                top.add(line);
            } else {
                trimmed = line.trim();
                if (!trimmed.equals("") && !trimmed.startsWith("//") && !trimmed.startsWith("#")) {
                    error("only comments and blank lines allowed between functions");
                }
                before.add(line);
            }
            if (line.replaceAll("\\s","").toLowerCase().startsWith(endFilePrefix.replaceAll("\\s",""))) {
                if (!inFilePrefix) {
                    error("excess '" + endFilePrefix + "'");
                }
                inFilePrefix = false;
            }
        }
    }

    void fill(SourceFile filledSF) {
        // copy beginning of file straight from filled file
        top = filledSF.top;

        // file in functions
        Iterator it = functions.iterator();
        while (it.hasNext()) {
            Function stubFunc = (Function)(it.next());
            Function filledFunc = (Function)filledSF.functionMap.get(stubFunc.name);
            stubFunc.fill(filledFunc);
        }
        if (filledSF.functionMap.size() > 0) {
            System.err.println("Warning: the following functions were present in the " +
                                "filled file but missing in the stub file and thus not copied:");
            it  = filledSF.functionMap.values().iterator();
            while (it.hasNext()) {
                System.err.println("        " + ((Function)(it.next())).name);
            }
        }
    }

    void output(PrintWriter out) {
        Iterator it = top.iterator();
        while (it.hasNext()) {
            out.println(it.next());
        }
        it = functions.iterator();
        while (it.hasNext()) {
            Function stubFunc = (Function)(it.next());
            stubFunc.output(out);
        }
    }
}