1 /*
   2  * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
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  24 
  25 #ifndef SHARE_VM_CI_CICALLPROFILE_HPP
  26 #define SHARE_VM_CI_CICALLPROFILE_HPP
  27 
  28 #include "ci/ciClassList.hpp"
  29 #include "memory/allocation.hpp"
  30 
  31 // ciCallProfile
  32 //
  33 // This class is used to determine the frequently called method
  34 // at some call site
  35 class ciCallProfile : StackObj {
  36 private:
  37   // Fields are initialized directly by ciMethod::call_profile_at_bci.
  38   friend class ciMethod;
  39 
  40   enum { MorphismLimit = 2 }; // Max call site's morphism we care about
  41   int  _limit;                // number of receivers have been determined
  42   int  _morphism;             // determined call site's morphism
  43   int  _count;                // # times has this call been executed
  44   int  _receiver_count[MorphismLimit + 1]; // # times receivers have been seen
  45   ciMethod* _method[MorphismLimit + 1];    // receivers methods
  46   ciKlass*  _receiver[MorphismLimit + 1];  // receivers (exact)
  47 
  48   ciCallProfile() {
  49     _limit = 0;
  50     _morphism    = 0;
  51     _count = -1;
  52     _receiver_count[0] = -1;
  53     _method[0]   = NULL;
  54     _receiver[0] = NULL;
  55   }
  56 
  57   void add_receiver(ciKlass* receiver, int receiver_count);
  58 
  59 public:
  60   // Note:  The following predicates return false for invalid profiles:
  61   bool      has_receiver(int i) { return _limit > i; }
  62   int       morphism()          { return _morphism; }
  63 
  64   int       count()             { return _count; }
  65   int       receiver_count(int i)  {
  66     assert(i < _limit, "out of Call Profile MorphismLimit");
  67     return _receiver_count[i];
  68   }
  69   float     receiver_prob(int i)  {
  70     assert(i < _limit, "out of Call Profile MorphismLimit");
  71     return (float)_receiver_count[i]/(float)_count;
  72   }
  73   ciMethod* method(int i)          {
  74     assert(i < _limit, "out of Call Profile MorphismLimit");
  75     return _method[i];
  76   }
  77   ciKlass*  receiver(int i)        {
  78     assert(i < _limit, "out of Call Profile MorphismLimit");
  79     return _receiver[i];
  80   }
  81 };
  82 
  83 #endif // SHARE_VM_CI_CICALLPROFILE_HPP