Mercurial > hg > truffle
view agent/src/share/classes/sun/jvm/hotspot/interpreter/BytecodeStream.java @ 271:818a18cd69a8
6730514: assertion failure in mangling code when expanding by 0 bytes
Summary: An expansion by 0 bytes was not anticipated when the assertion was composed.
Reviewed-by: jjh, jcoomes, apetrusenko
author | jmasa |
---|---|
date | Wed, 30 Jul 2008 11:54:00 -0700 |
parents | a61af66fc99e |
children | c18cbe5936b8 |
line wrap: on
line source
/* * Copyright 2001-2002 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. * */ package sun.jvm.hotspot.interpreter; import sun.jvm.hotspot.oops.*; import sun.jvm.hotspot.runtime.*; import sun.jvm.hotspot.utilities.*; public class BytecodeStream { private Method _method; // reading position private int _bci; // bci if current bytecode private int _next_bci; // bci of next bytecode private int _end_bci; // bci after the current iteration interval // last bytecode read private int _code; private boolean _is_wide; // Construction public BytecodeStream(Method method) { _method = method; setInterval(0, (int) method.getCodeSize()); } // Iteration control public void setInterval(int beg_bci, int end_bci) { if (Assert.ASSERTS_ENABLED) { Assert.that(0 <= beg_bci && beg_bci <= _method.getCodeSize(), "illegal beg_bci"); Assert.that(0 <= end_bci && end_bci <= _method.getCodeSize(), "illegal end_bci"); } // setup of iteration pointers _bci = beg_bci; _next_bci = beg_bci; _end_bci = end_bci; } public void setStart(int beg_bci) { setInterval(beg_bci, (int) _method.getCodeSize()); } // Iteration public int next() { int code; // set reading position _bci = _next_bci; if (isLastBytecode()) { // indicate end of bytecode stream code = Bytecodes._illegal; } else { // get bytecode int rawCode = Bytecodes.codeAt(_method, _bci); code = 0; // Make javac happy try { code = Bytecodes.javaCode(rawCode); } catch (AssertionFailure e) { e.printStackTrace(); Assert.that(false, "Failure occurred at bci " + _bci + " in method " + _method.externalNameAndSignature()); } // set next bytecode position // int l = Bytecodes.lengthFor(code); if (l == 0) l = Bytecodes.lengthAt(_method, _bci); _next_bci += l; if (Assert.ASSERTS_ENABLED) { Assert.that(_bci < _next_bci, "length must be > 0"); } // set attributes _is_wide = false; // check for special (uncommon) cases if (code == Bytecodes._wide) { code = _method.getBytecodeOrBPAt(_bci + 1); _is_wide = true; } if (Assert.ASSERTS_ENABLED) { Assert.that(Bytecodes.isJavaCode(code), "sanity check"); } } _code = code; return _code; } // Stream attributes public Method method() { return _method; } public int bci() { return _bci; } public int nextBCI() { return _next_bci; } public int endBCI() { return _end_bci; } public int code() { return _code; } public boolean isWide() { return _is_wide; } public boolean isActiveBreakpoint() { return Bytecodes.isActiveBreakpointAt(_method, _bci); } public boolean isLastBytecode() { return _next_bci >= _end_bci; } // State changes public void setNextBCI(int bci) { if (Assert.ASSERTS_ENABLED) { Assert.that(0 <= bci && bci <= _method.getCodeSize(), "illegal bci"); } _next_bci = bci; } // Bytecode-specific attributes public int dest() { return bci() + _method.getBytecodeShortArg(bci() + 1); } public int dest_w() { return bci() + _method.getBytecodeIntArg(bci() + 1); } // Unsigned indices, widening public int getIndex() { return (isWide()) ? (_method.getBytecodeShortArg(bci() + 2) & 0xFFFF) : (_method.getBytecodeOrBPAt(bci() + 1) & 0xFF); } public int getIndexBig() { return _method.getBytecodeShortArg(bci() + 1); } // Fetch at absolute BCI (for manual parsing of certain bytecodes) public int codeAt(int bci) { return _method.getBytecodeOrBPAt(bci); } }