1 /* 2 * Copyright (c) 1997, 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 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_LIBADT_SET_HPP 26 #define SHARE_VM_LIBADT_SET_HPP 27 28 #include "libadt/port.hpp" 29 #include "memory/allocation.hpp" 30 31 // Sets - An Abstract Data Type 32 33 //INTERFACE 34 35 class SparseSet; 36 class VectorSet; 37 class ListSet; 38 class CoSet; 39 40 class ostream; 41 class SetI_; 42 43 // These sets can grow or shrink, based on the initial size and the largest 44 // element currently in them. Basically, they allow a bunch of bits to be 45 // grouped together, tested, set & cleared, intersected, etc. The basic 46 // Set class is an abstract class, and cannot be constructed. Instead, 47 // one of VectorSet, SparseSet, or ListSet is created. Each variation has 48 // different asymptotic running times for different operations, and different 49 // constants of proportionality as well. 50 // {n = number of elements, N = largest element} 51 52 // VectorSet SparseSet ListSet 53 // Create O(N) O(1) O(1) 54 // Clear O(N) O(1) O(1) 55 // Insert O(1) O(1) O(log n) 56 // Delete O(1) O(1) O(log n) 57 // Member O(1) O(1) O(log n) 58 // Size O(N) O(1) O(1) 59 // Copy O(N) O(n) O(n) 60 // Union O(N) O(n) O(n log n) 61 // Intersect O(N) O(n) O(n log n) 62 // Difference O(N) O(n) O(n log n) 63 // Equal O(N) O(n) O(n log n) 64 // ChooseMember O(N) O(1) O(1) 65 // Sort O(1) O(n log n) O(1) 66 // Forall O(N) O(n) O(n) 67 // Complement O(1) O(1) O(1) 68 69 // TIME: N/32 n 8*n Accesses 70 // SPACE: N/8 4*N+4*n 8*n Bytes 71 72 // Create: Make an empty set 73 // Clear: Remove all the elements of a Set 74 // Insert: Insert an element into a Set; duplicates are ignored 75 // Delete: Removes an element from a Set 76 // Member: Tests for membership in a Set 77 // Size: Returns the number of members of a Set 78 // Copy: Copy or assign one Set to another 79 // Union: Union 2 sets together 80 // Intersect: Intersect 2 sets together 81 // Difference: Compute A & !B; remove from set A those elements in set B 82 // Equal: Test for equality between 2 sets 83 // ChooseMember Pick a random member 84 // Sort: If no other operation changes the set membership, a following 85 // Forall will iterate the members in ascending order. 86 // Forall: Iterate over the elements of a Set. Operations that modify 87 // the set membership during iteration work, but the iterator may 88 // skip any member or duplicate any member. 89 // Complement: Only supported in the Co-Set variations. It adds a small 90 // constant-time test to every Set operation. 91 // 92 // PERFORMANCE ISSUES: 93 // If you "cast away" the specific set variation you are using, and then do 94 // operations on the basic "Set" object you will pay a virtual function call 95 // to get back the specific set variation. On the other hand, using the 96 // generic Set means you can change underlying implementations by just 97 // changing the initial declaration. Examples: 98 // void foo(VectorSet vs1, VectorSet vs2) { vs1 |= vs2; } 99 // "foo" must be called with a VectorSet. The vector set union operation 100 // is called directly. 101 // void foo(Set vs1, Set vs2) { vs1 |= vs2; } 102 // "foo" may be called with *any* kind of sets; suppose it is called with 103 // VectorSets. Two virtual function calls are used to figure out the that vs1 104 // and vs2 are VectorSets. In addition, if vs2 is not a VectorSet then a 105 // temporary VectorSet copy of vs2 will be made before the union proceeds. 106 // 107 // VectorSets have a small constant. Time and space are proportional to the 108 // largest element. Fine for dense sets and largest element < 10,000. 109 // SparseSets have a medium constant. Time is proportional to the number of 110 // elements, space is proportional to the largest element. 111 // Fine (but big) with the largest element < 100,000. 112 // ListSets have a big constant. Time *and space* are proportional to the 113 // number of elements. They work well for a few elements of *any* size 114 // (i.e. sets of pointers)! 115 116 //------------------------------Set-------------------------------------------- 117 class Set : public ResourceObj { 118 public: 119 120 // Creates a new, empty set. 121 // DO NOT CONSTRUCT A Set. THIS IS AN ABSTRACT CLASS, FOR INHERITENCE ONLY 122 Set(Arena *arena) : _set_arena(arena) {}; 123 124 // Creates a new set from an existing set 125 // DO NOT CONSTRUCT A Set. THIS IS AN ABSTRACT CLASS, FOR INHERITENCE ONLY 126 Set(const Set &) {}; 127 128 // Set assignment; deep-copy guts 129 virtual Set &operator =(const Set &s)=0; 130 virtual Set &clone(void) const=0; 131 132 // Virtual destructor 133 virtual ~Set() {}; 134 135 // Add member to set 136 virtual Set &operator <<=(uint elem)=0; 137 // virtual Set operator << (uint elem); 138 139 // Delete member from set 140 virtual Set &operator >>=(uint elem)=0; 141 // virtual Set operator >> (uint elem); 142 143 // Membership test. Result is Zero (absent)/ Non-Zero (present) 144 virtual int operator [](uint elem) const=0; 145 146 // Intersect sets 147 virtual Set &operator &=(const Set &s)=0; 148 // virtual Set operator & (const Set &s) const; 149 150 // Union sets 151 virtual Set &operator |=(const Set &s)=0; 152 // virtual Set operator | (const Set &s) const; 153 154 // Difference sets 155 virtual Set &operator -=(const Set &s)=0; 156 // virtual Set operator - (const Set &s) const; 157 158 // Tests for equality. Result is Zero (false)/ Non-Zero (true) 159 virtual int operator ==(const Set &s) const=0; 160 int operator !=(const Set &s) const { return !(*this == s); } 161 virtual int disjoint(const Set &s) const=0; 162 163 // Tests for strict subset. Result is Zero (false)/ Non-Zero (true) 164 virtual int operator < (const Set &s) const=0; 165 int operator > (const Set &s) const { return s < *this; } 166 167 // Tests for subset. Result is Zero (false)/ Non-Zero (true) 168 virtual int operator <=(const Set &s) const=0; 169 int operator >=(const Set &s) const { return s <= *this; } 170 171 // Return any member of the Set. Undefined if the Set is empty. 172 virtual uint getelem(void) const=0; 173 174 // Clear all the elements in the Set 175 virtual void Clear(void)=0; 176 177 // Return the number of members in the Set 178 virtual uint Size(void) const=0; 179 180 // If an iterator follows a "Sort()" without any Set-modifying operations 181 // inbetween then the iterator will visit the elements in ascending order. 182 virtual void Sort(void)=0; 183 184 // Convert a set to printable string in an allocated buffer. 185 // The caller must deallocate the string. 186 virtual char *setstr(void) const; 187 188 // Print the Set on "stdout". Can be conveniently called in the debugger 189 void print() const; 190 191 // Parse text from the string into the Set. Return length parsed. 192 virtual int parse(const char *s); 193 194 // Convert a generic Set to a specific Set 195 /* Removed for MCC BUG 196 virtual operator const SparseSet* (void) const; 197 virtual operator const VectorSet* (void) const; 198 virtual operator const ListSet * (void) const; 199 virtual operator const CoSet * (void) const; */ 200 virtual const SparseSet *asSparseSet(void) const; 201 virtual const VectorSet *asVectorSet(void) const; 202 virtual const ListSet *asListSet (void) const; 203 virtual const CoSet *asCoSet (void) const; 204 205 // Hash the set. Sets of different types but identical elements will NOT 206 // hash the same. Same set type, same elements WILL hash the same. 207 virtual int hash() const = 0; 208 209 protected: 210 friend class SetI; 211 friend class CoSet; 212 virtual class SetI_ *iterate(uint&) const=0; 213 214 // Need storeage for the set 215 Arena *_set_arena; 216 }; 217 typedef Set&((*Set_Constructor)(Arena *arena)); 218 extern Set &ListSet_Construct(Arena *arena); 219 extern Set &VectorSet_Construct(Arena *arena); 220 extern Set &SparseSet_Construct(Arena *arena); 221 222 //------------------------------Iteration-------------------------------------- 223 // Loop thru all elements of the set, setting "elem" to the element numbers 224 // in random order. Inserted or deleted elements during this operation may 225 // or may not be iterated over; untouched elements will be affected once. 226 227 // Usage: for( SetI i(s); i.test(); i++ ) { body = i.elem; } ...OR... 228 // for( i.reset(s); i.test(); i++ ) { body = i.elem; } 229 230 class SetI_ : public ResourceObj { 231 protected: 232 friend class SetI; 233 virtual ~SetI_(); 234 virtual uint next(void)=0; 235 virtual int test(void)=0; 236 }; 237 238 class SetI { 239 protected: 240 SetI_ *impl; 241 public: 242 uint elem; // The publically accessible element 243 244 SetI( const Set *s ) { impl = s->iterate(elem); } 245 ~SetI() { delete impl; } 246 void reset( const Set *s ) { delete impl; impl = s->iterate(elem); } 247 void operator ++(void) { elem = impl->next(); } 248 int test(void) { return impl->test(); } 249 }; 250 251 #endif // SHARE_VM_LIBADT_SET_HPP