1 /*
   2  * Copyright (c) 1997, 2011, 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
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_LIBADT_VECTSET_HPP
  26 #define SHARE_VM_LIBADT_VECTSET_HPP
  27 
  28 #include "libadt/set.hpp"
  29 
  30 // Vector Sets - An Abstract Data Type
  31 //INTERFACE
  32 
  33 // These sets can grow or shrink, based on the initial size and the largest
  34 // element currently in them.  Slow and bulky for sparse sets, these sets
  35 // are super for dense sets.  They are fast and compact when dense.
  36 
  37 // TIME:
  38 // O(1) - Insert, Delete, Member, Sort
  39 // O(max_element) - Create, Clear, Size, Copy, Union, Intersect, Difference,
  40 //                  Equal, ChooseMember, Forall
  41 
  42 // SPACE: (max_element)/(8*sizeof(int))
  43 
  44 
  45 //------------------------------VectorSet--------------------------------------
  46 class VectorSet : public Set {
  47 friend class VectorSetI;        // Friendly iterator class
  48 protected:
  49   uint size;                    // Size of data IN LONGWORDS (32bits)
  50   uint32 *data;                 // The data, bit packed
  51 
  52   void slamin( const VectorSet& s );     // Initialize one set with another
  53   int compare(const VectorSet &s) const; // Compare set contents
  54   void grow(uint newsize);               // Grow vector to required bitsize
  55 
  56 public:
  57   VectorSet(Arena *arena);                      // Creates a new, empty set.
  58   VectorSet(const VectorSet &s) : Set(s._set_arena) {slamin(s);} // Set clone; deep-copy guts
  59   Set &operator =(const Set &s);                // Set clone; deep-copy guts
  60   VectorSet &operator =(const VectorSet &s)     // Set clone; deep-copy guts
  61   { if( &s != this ) { slamin(s); } return *this; }
  62   ~VectorSet() {}
  63   Set &clone(void) const { return *(new VectorSet(*this)); }
  64 
  65   Set &operator <<=(uint elem);          // Add member to set
  66   VectorSet operator << (uint elem)      // Add member to new set
  67   { VectorSet foo(*this); foo <<= elem; return foo; }
  68   Set &operator >>=(uint elem);          // Delete member from set
  69   VectorSet operator >> (uint elem)      // Delete member from new set
  70   { VectorSet foo(*this); foo >>= elem; return foo; }
  71 
  72   VectorSet &operator &=(const VectorSet &s); // Intersect sets into first set
  73   Set       &operator &=(const Set       &s); // Intersect sets into first set
  74   VectorSet operator & (const VectorSet &s) const
  75   { VectorSet foo(*this); foo &= s; return foo; }
  76 
  77   VectorSet &operator |=(const VectorSet &s); // Intersect sets into first set
  78   Set       &operator |=(const Set       &s); // Intersect sets into first set
  79   VectorSet operator | (const VectorSet &s) const
  80   { VectorSet foo(*this); foo |= s; return foo; }
  81 
  82   VectorSet &operator -=(const VectorSet &s); // Intersect sets into first set
  83   Set       &operator -=(const Set       &s); // Intersect sets into first set
  84   VectorSet operator - (const VectorSet &s) const
  85   { VectorSet foo(*this); foo -= s; return foo; }
  86 
  87   int operator ==(const VectorSet &s) const;  // True if sets are equal
  88   int operator ==(const Set       &s) const;  // True if sets are equal
  89   int operator < (const VectorSet &s) const;  // True if strict subset
  90   int operator < (const Set       &s) const;  // True if strict subset
  91   int operator <=(const VectorSet &s) const;  // True if subset relation holds.
  92   int operator <=(const Set       &s) const;  // True if subset relation holds.
  93   int disjoint   (const Set       &s) const;  // True if sets are disjoint
  94 
  95   int operator [](uint elem) const; // Test for membership
  96   uint getelem(void) const;         // Return a random element
  97   void Clear(void);                 // Clear a set
  98   uint Size(void) const;            // Number of elements in the Set.
  99   void Sort(void);                  // Sort before iterating
 100   int hash() const;                 // Hash function
 101   void Reset(void) {                // Reset a set
 102     memset( data, 0, size*sizeof(uint32) );
 103   }
 104 
 105   /* Removed for MCC BUG
 106      operator const VectorSet* (void) const { return this; } */
 107   const VectorSet *asVectorSet() const { return this; }
 108 
 109   // Expose internals for speed-critical fast iterators
 110   uint word_size() const { return size; }
 111   uint32 *EXPOSE() const { return data; }
 112 
 113   // Fast inlined "test and set".  Replaces the idiom:
 114   //     if( visited[idx] ) return;
 115   //     visited <<= idx;
 116   // With:
 117   //     if( visited.test_set(idx) ) return;
 118   //
 119   int test_set( uint elem ) {
 120     uint word = elem >> 5;           // Get the longword offset
 121     if( word >= size )               // Beyond the last?
 122       return test_set_grow(elem);    // Then grow; set; return 0;
 123     uint32 mask = 1L << (elem & 31); // Get bit mask
 124     uint32 datum = data[word] & mask;// Get bit
 125     data[word] |= mask;              // Set bit
 126     return datum;                    // Return bit
 127   }
 128   int test_set_grow( uint elem ) {    // Insert & return 0;
 129     (*this) <<= elem;                 // Insert into set
 130     return 0;                         // Return 0!
 131   }
 132 
 133   // Fast inlined test
 134   int test( uint elem ) const {
 135     uint word = elem >> 5;      // Get the longword offset
 136     if( word >= size ) return 0; // Beyond the last?
 137     uint32 mask = 1L << (elem & 31); // Get bit mask
 138     return data[word] & mask;   // Get bit
 139   }
 140 
 141   // Fast inlined set
 142   void set( uint elem ) {
 143     uint word = elem >> 5;      // Get the longword offset
 144     if( word >= size ) {        // Beyond the last?
 145       test_set_grow(elem);      // Then grow and set
 146     } else {
 147       uint32 mask = 1L << (elem & 31); // Get bit mask
 148       data[word] |= mask;       // Set bit
 149     }
 150   }
 151 








 152 
 153 private:
 154   SetI_ *iterate(uint&) const;
 155 };
 156 
 157 //------------------------------Iteration--------------------------------------
 158 // Loop thru all elements of the set, setting "elem" to the element numbers
 159 // in random order.  Inserted or deleted elements during this operation may
 160 // or may not be iterated over; untouched elements will be affected once.
 161 // Usage:  for( VectorSetI i(s); i.test(); i++ ) { body = i.elem; }
 162 
 163 class VectorSetI : public StackObj {
 164   friend class VectorSet;
 165   const VectorSet *s;
 166   uint i, j;
 167   uint32 mask;
 168   uint next(void);
 169 
 170 public:
 171   uint elem;                    // The publically accessible element
 172 
 173   VectorSetI( const VectorSet *vset ) :
 174     s(vset),
 175     i((uint)-1L),
 176     j((uint)-1L),
 177     mask((unsigned)(1L<<31)) {
 178     elem = next();
 179   }
 180 
 181   void operator ++(void) { elem = next(); }
 182   int test(void) { return i < s->size; }
 183 };
 184 
 185 #endif // SHARE_VM_LIBADT_VECTSET_HPP
--- EOF ---