ageTable.hpp

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/* Copyright 1994, 1995 LongView Technologies L.L.C. $Revision: 1.5 $ */
/* Copyright (c) 2006, Sun Microsystems, Inc.
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// Age table for feedback-mediated tenuring (generation scavenging).
// Note: all sizes are in oopSize
class ageTable: public CHeapObj {
 public:
  // instance variables
  enum { table_size = markOopDesc::max_age + 1 };
  int sizes[table_size];
  
  // constructor
  ageTable();
  
  // operations
  void clear() { set_words(&sizes[0], table_size, 0); }
  void add(memOop p, int oop_size) {
    int age = p->mark()->age();
    assert(age >= 0 && age < table_size, "invalid age of object");
    sizes[age] += oop_size; }
  
  int tenure_size(int age);
  int tenuring_threshold(int oop_size);
};

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