view src/share/vm/ci/ciSymbol.hpp @ 3979:4dfb2df418f2

6484982: G1: process references during evacuation pauses Summary: G1 now uses two reference processors - one is used by concurrent marking and the other is used by STW GCs (both full and incremental evacuation pauses). In an evacuation pause, the reference processor is embedded into the closures used to scan objects. Doing so causes causes reference objects to be 'discovered' by the reference processor. At the end of the evacuation pause, these discovered reference objects are processed - preserving (and copying) referent objects (and their reachable graphs) as appropriate. Reviewed-by: ysr, jwilhelm, brutisso, stefank, tonyp
author johnc
date Thu, 22 Sep 2011 10:57:37 -0700
parents 1d1603768966
children 0654ee04b214 1d7922586cf6
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/*
 * Copyright (c) 1999, 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.
 *
 * 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.
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 */

#ifndef SHARE_VM_CI_CISYMBOL_HPP
#define SHARE_VM_CI_CISYMBOL_HPP

#include "ci/ciObject.hpp"
#include "ci/ciObjectFactory.hpp"
#include "classfile/vmSymbols.hpp"
#include "oops/symbol.hpp"

// ciSymbol
//
// This class represents a Symbol* in the HotSpot virtual
// machine.
class ciSymbol : public ResourceObj {
  Symbol* _symbol;
  uint _ident;

  CI_PACKAGE_ACCESS
  // These friends all make direct use of get_symbol:
  friend class ciEnv;
  friend class ciInstanceKlass;
  friend class ciSignature;
  friend class ciMethod;
  friend class ciObjArrayKlass;

private:
  const vmSymbols::SID _sid;
  DEBUG_ONLY( bool sid_ok() { return vmSymbols::find_sid(get_symbol()) == _sid; } )

  ciSymbol(Symbol* s);  // normal case, for symbols not mentioned in vmSymbols
  ciSymbol(Symbol* s, vmSymbols::SID sid);   // for use with vmSymbols

  Symbol* get_symbol() const { return _symbol; }

  const char* type_string() { return "ciSymbol"; }

  void print_impl(outputStream* st);

  // This is public in Symbol* but private here, because the base can move:
  const jbyte* base();

  // Make a ciSymbol from a C string (implementation).
  static ciSymbol* make_impl(const char* s);

  void set_ident(uint id) { _ident = id; }
public:
  // A number unique to this object.
  uint ident() { return _ident; }

  // The enumeration ID from vmSymbols, or vmSymbols::NO_SID if none.
  vmSymbols::SID sid() const { return _sid; }

  // The text of the symbol as a null-terminated utf8 string.
  const char* as_utf8();
  int         utf8_length();

  // Return the i-th utf8 byte, where i < utf8_length
  int         byte_at(int i);

  // Tests if the symbol starts with the given prefix.
  bool starts_with(const char* prefix, int len) const;

  // Determines where the symbol contains the given substring.
  int index_of_at(int i, const char* str, int len) const;

  void print_symbol_on(outputStream* st);
  void print_symbol() {
    print_symbol_on(tty);
  }

  // Make a ciSymbol from a C string.
  // Consider adding to vmSymbols.hpp instead of using this constructor.
  // (Your code will be less subject to typographical bugs.)
  static ciSymbol* make(const char* s);

#define CI_SYMBOL_DECLARE(name, ignore_def) \
  static ciSymbol* name() { return ciObjectFactory::vm_symbol_at(vmSymbols::VM_SYMBOL_ENUM_NAME(name)); }
  VM_SYMBOLS_DO(CI_SYMBOL_DECLARE, CI_SYMBOL_DECLARE)
#undef CI_SYMBOL_DECLARE

  void print() {
    _symbol->print();
  }

  // Are two ciSymbols equal?
  bool equals(ciSymbol* obj) { return this->_symbol == obj->get_symbol(); }
};

#endif // SHARE_VM_CI_CISYMBOL_HPP