view src/share/vm/ci/ciCallProfile.hpp @ 3762:5c0a3c1858b1

7048782: CMS: assert(last_chunk_index_to_check<= last_chunk_index) failed: parCardTableModRefBS.cpp:359 Summary: The LNC array is sized before the start of a scavenge, while the heap may expand during a scavenge. With CMS, the last block of an arbitrary suffice of the LNC array may expand due to coalition with the expansion delta. We now take care not to attempt access past the end of the LNC array. LNC array code will be cleaned up and suitably encapsulated as part of the forthcoming performance RFE 7043675. Reviewed-by: brutisso
author ysr
date Thu, 02 Jun 2011 10:23:36 -0700
parents c760f78e0a53
children 66ecfc755c86 f56542cb325a
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/*
 * Copyright (c) 1999, 2010, 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_CICALLPROFILE_HPP
#define SHARE_VM_CI_CICALLPROFILE_HPP

#include "ci/ciClassList.hpp"
#include "memory/allocation.hpp"

// ciCallProfile
//
// This class is used to determine the frequently called method
// at some call site
class ciCallProfile : StackObj {
private:
  // Fields are initialized directly by ciMethod::call_profile_at_bci.
  friend class ciMethod;

  enum { MorphismLimit = 2 }; // Max call site's morphism we care about
  int  _limit;                // number of receivers have been determined
  int  _morphism;             // determined call site's morphism
  int  _count;                // # times has this call been executed
  int  _receiver_count[MorphismLimit + 1]; // # times receivers have been seen
  ciMethod* _method[MorphismLimit + 1];    // receivers methods
  ciKlass*  _receiver[MorphismLimit + 1];  // receivers (exact)

  ciCallProfile() {
    _limit = 0;
    _morphism    = 0;
    _count = -1;
    _receiver_count[0] = -1;
    _method[0]   = NULL;
    _receiver[0] = NULL;
  }

  void add_receiver(ciKlass* receiver, int receiver_count);

public:
  // Note:  The following predicates return false for invalid profiles:
  bool      has_receiver(int i) { return _limit > i; }
  int       morphism()          { return _morphism; }

  int       count()             { return _count; }
  int       receiver_count(int i)  {
    assert(i < _limit, "out of Call Profile MorphismLimit");
    return _receiver_count[i];
  }
  float     receiver_prob(int i)  {
    assert(i < _limit, "out of Call Profile MorphismLimit");
    return (float)_receiver_count[i]/(float)_count;
  }
  ciMethod* method(int i)          {
    assert(i < _limit, "out of Call Profile MorphismLimit");
    return _method[i];
  }
  ciKlass*  receiver(int i)        {
    assert(i < _limit, "out of Call Profile MorphismLimit");
    return _receiver[i];
  }
};

#endif // SHARE_VM_CI_CICALLPROFILE_HPP