Mercurial > hg > truffle
view src/share/vm/interpreter/interpreter.hpp @ 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 | 98cb887364d3 |
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/* * Copyright 1997-2007 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. * */ // This file contains the platform-independant parts // of the interpreter and the interpreter generator. //------------------------------------------------------------------------------------------------------------------------ // An InterpreterCodelet is a piece of interpreter code. All // interpreter code is generated into little codelets which // contain extra information for debugging and printing purposes. class InterpreterCodelet: public Stub { friend class VMStructs; private: int _size; // the size in bytes const char* _description; // a description of the codelet, for debugging & printing Bytecodes::Code _bytecode; // associated bytecode if any public: // Initialization/finalization void initialize(int size) { _size = size; } void finalize() { ShouldNotCallThis(); } // General info/converters int size() const { return _size; } static int code_size_to_size(int code_size) { return round_to(sizeof(InterpreterCodelet), CodeEntryAlignment) + code_size; } // Code info address code_begin() const { return (address)this + round_to(sizeof(InterpreterCodelet), CodeEntryAlignment); } address code_end() const { return (address)this + size(); } // Debugging void verify(); void print(); // Interpreter-specific initialization void initialize(const char* description, Bytecodes::Code bytecode); // Interpreter-specific attributes int code_size() const { return code_end() - code_begin(); } const char* description() const { return _description; } Bytecodes::Code bytecode() const { return _bytecode; } }; // Define a prototype interface DEF_STUB_INTERFACE(InterpreterCodelet); //------------------------------------------------------------------------------------------------------------------------ // A CodeletMark serves as an automatic creator/initializer for Codelets // (As a subclass of ResourceMark it automatically GC's the allocated // code buffer and assemblers). class CodeletMark: ResourceMark { private: InterpreterCodelet* _clet; InterpreterMacroAssembler** _masm; CodeBuffer _cb; int codelet_size() { // Request the whole code buffer (minus a little for alignment). // The commit call below trims it back for each codelet. int codelet_size = AbstractInterpreter::code()->available_space() - 2*K; // Guarantee there's a little bit of code space left. guarantee (codelet_size > 0 && (size_t)codelet_size > 2*K, "not enough space for interpreter generation"); return codelet_size; } public: CodeletMark( InterpreterMacroAssembler*& masm, const char* description, Bytecodes::Code bytecode = Bytecodes::_illegal): _clet((InterpreterCodelet*)AbstractInterpreter::code()->request(codelet_size())), _cb(_clet->code_begin(), _clet->code_size()) { // request all space (add some slack for Codelet data) assert (_clet != NULL, "we checked not enough space already"); // initialize Codelet attributes _clet->initialize(description, bytecode); // create assembler for code generation masm = new InterpreterMacroAssembler(&_cb); _masm = &masm; } ~CodeletMark() { // align so printing shows nop's instead of random code at the end (Codelets are aligned) (*_masm)->align(wordSize); // make sure all code is in code buffer (*_masm)->flush(); // commit Codelet AbstractInterpreter::code()->commit((*_masm)->code()->pure_code_size()); // make sure nobody can use _masm outside a CodeletMark lifespan *_masm = NULL; } }; // Wrapper classes to produce Interpreter/InterpreterGenerator from either // the c++ interpreter or the template interpreter. class Interpreter: public CC_INTERP_ONLY(CppInterpreter) NOT_CC_INTERP(TemplateInterpreter) { public: // Debugging/printing static InterpreterCodelet* codelet_containing(address pc) { return (InterpreterCodelet*)_code->stub_containing(pc); } #include "incls/_interpreter_pd.hpp.incl" };