alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (icBuffer.hpp)

This example Java source code file (icBuffer.hpp) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

allstatic, assert, codeentryalignment, codestrings, compiledicholder, icstub, icstub_from_destination_address, icstubinterface, inlinecachebuffer, null, product_return, share_vm_code_icbuffer_hpp, stubqueue

The icBuffer.hpp Java example source code

/*
 * Copyright (c) 1997, 2013, 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.
 *
 */

#ifndef SHARE_VM_CODE_ICBUFFER_HPP
#define SHARE_VM_CODE_ICBUFFER_HPP

#include "asm/codeBuffer.hpp"
#include "code/stubs.hpp"
#include "interpreter/bytecodes.hpp"
#include "memory/allocation.hpp"

//
// For CompiledIC's:
//
// In cases where we do not have MT-safe state transformation,
// we go to a transition state, using ICStubs. At a safepoint,
// the inline caches are transferred from the transitional code:
//
//    instruction_address --> 01 set xxx_oop, Ginline_cache_klass
//                            23 jump_to Gtemp, yyyy
//                            4  nop

class ICStub: public Stub {
 private:
  int                 _size;       // total size of the stub incl. code
  address             _ic_site;    // points at call instruction of owning ic-buffer
  /* stub code follows here */
 protected:
  friend class ICStubInterface;
  // This will be called only by ICStubInterface
  void    initialize(int size,
                     CodeStrings strings)        { _size = size; _ic_site = NULL; }
  void    finalize(); // called when a method is removed

  // General info
  int     size() const                           { return _size; }
  static  int code_size_to_size(int code_size)   { return round_to(sizeof(ICStub), CodeEntryAlignment) + code_size; }

 public:
  // Creation
  void set_stub(CompiledIC *ic, void* cached_value, address dest_addr);

  // Code info
  address code_begin() const                     { return (address)this + round_to(sizeof(ICStub), CodeEntryAlignment); }
  address code_end() const                       { return (address)this + size(); }

  // Call site info
  address ic_site() const                        { return _ic_site; }
  void    clear();
  bool    is_empty() const                       { return _ic_site == NULL; }

  // stub info
  address destination() const;  // destination of jump instruction
  void* cached_value() const;   // cached_value for stub

  // Debugging
  void    verify()            PRODUCT_RETURN;
  void    print()             PRODUCT_RETURN;

  // Creation
  friend ICStub* ICStub_from_destination_address(address destination_address);
};

// ICStub Creation
inline ICStub* ICStub_from_destination_address(address destination_address) {
  ICStub* stub = (ICStub*) (destination_address - round_to(sizeof(ICStub), CodeEntryAlignment));
  #ifdef ASSERT
  stub->verify();
  #endif
  return stub;
}

class InlineCacheBuffer: public AllStatic {
 private:
  // friends
  friend class ICStub;

  static int ic_stub_code_size();

  static StubQueue* _buffer;
  static ICStub*    _next_stub;

  static CompiledICHolder* _pending_released;
  static int _pending_count;

  static StubQueue* buffer()                         { return _buffer;         }
  static void       set_next_stub(ICStub* next_stub) { _next_stub = next_stub; }
  static ICStub*    get_next_stub()                  { return _next_stub;      }

  static void       init_next_stub();

  static ICStub* new_ic_stub();


  // Machine-dependent implementation of ICBuffer
  static void    assemble_ic_buffer_code(address code_begin, void* cached_value, address entry_point);
  static address ic_buffer_entry_point  (address code_begin);
  static void*   ic_buffer_cached_value (address code_begin);

 public:

    // Initialization; must be called before first usage
  static void initialize();

  // Access
  static bool contains(address instruction_address);

    // removes the ICStubs after backpatching
  static void update_inline_caches();

  // for debugging
  static bool is_empty();

  static void release_pending_icholders();
  static void queue_for_release(CompiledICHolder* icholder);
  static int pending_icholder_count() { return _pending_count; }

  // New interface
  static void    create_transition_stub(CompiledIC *ic, void* cached_value, address entry);
  static address ic_destination_for(CompiledIC *ic);
  static void*   cached_value_for(CompiledIC *ic);
};

#endif // SHARE_VM_CODE_ICBUFFER_HPP

Other Java examples (source code examples)

Here is a short list of links related to this Java icBuffer.hpp source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2024 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.