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 "memory/allocation.hpp" 29 30 // Sets - An Abstract Data Type 31 32 class SparseSet; 33 class VectorSet; 34 class ListSet; 35 class CoSet; 36 37 class ostream; 38 class SetI_; 39 40 // These sets can grow or shrink, based on the initial size and the largest 41 // element currently in them. Basically, they allow a bunch of bits to be 42 // grouped together, tested, set & cleared, intersected, etc. The basic 43 // Set class is an abstract class, and cannot be constructed. Instead, 44 // one of VectorSet, SparseSet, or ListSet is created. Each variation has 45 // different asymptotic running times for different operations, and different 46 // constants of proportionality as well. 47 // {n = number of elements, N = largest element} 48 49 // VectorSet SparseSet ListSet 50 // Create O(N) O(1) O(1) 51 // Clear O(N) O(1) O(1) 52 // Insert O(1) O(1) O(log n) 53 // Delete O(1) O(1) O(log n) 54 // Member O(1) O(1) O(log n) 55 // Size O(N) O(1) O(1) 56 // Copy O(N) O(n) O(n) 57 // Union O(N) O(n) O(n log n) 58 // Intersect O(N) O(n) O(n log n) 59 // Difference O(N) O(n) O(n log n) 60 // Equal O(N) O(n) O(n log n) 61 // ChooseMember O(N) O(1) O(1) 62 // Sort O(1) O(n log n) O(1) 63 // Forall O(N) O(n) O(n) 64 // Complement O(1) O(1) O(1) 65 66 // TIME: N/32 n 8*n Accesses 67 // SPACE: N/8 4*N+4*n 8*n Bytes 68 69 // Create: Make an empty set 70 // Clear: Remove all the elements of a Set 71 // Insert: Insert an element into a Set; duplicates are ignored 72 // Delete: Removes an element from a Set 73 // Member: Tests for membership in a Set 74 // Size: Returns the number of members of a Set 75 // Copy: Copy or assign one Set to another 76 // Union: Union 2 sets together 77 // Intersect: Intersect 2 sets together 78 // Difference: Compute A & !B; remove from set A those elements in set B 79 // Equal: Test for equality between 2 sets 80 // ChooseMember Pick a random member 81 // Sort: If no other operation changes the set membership, a following 82 // Forall will iterate the members in ascending order. 83 // Forall: Iterate over the elements of a Set. Operations that modify 84 // the set membership during iteration work, but the iterator may 85 // skip any member or duplicate any member. 86 // Complement: Only supported in the Co-Set variations. It adds a small 87 // constant-time test to every Set operation. 88 // 89 // PERFORMANCE ISSUES: 90 // If you "cast away" the specific set variation you are using, and then do 91 // operations on the basic "Set" object you will pay a virtual function call 92 // to get back the specific set variation. On the other hand, using the 93 // generic Set means you can change underlying implementations by just 94 // changing the initial declaration. Examples: 95 // void foo(VectorSet vs1, VectorSet vs2) { vs1 |= vs2; } 96 // "foo" must be called with a VectorSet. The vector set union operation 97 // is called directly. 98 // void foo(Set vs1, Set vs2) { vs1 |= vs2; } 99 // "foo" may be called with *any* kind of sets; suppose it is called with 100 // VectorSets. Two virtual function calls are used to figure out the that vs1 101 // and vs2 are VectorSets. In addition, if vs2 is not a VectorSet then a 102 // temporary VectorSet copy of vs2 will be made before the union proceeds. 103 // 104 // VectorSets have a small constant. Time and space are proportional to the 105 // largest element. Fine for dense sets and largest element < 10,000. 106 // SparseSets have a medium constant. Time is proportional to the number of 107 // elements, space is proportional to the largest element. 108 // Fine (but big) with the largest element < 100,000. 109 // ListSets have a big constant. Time *and space* are proportional to the 110 // number of elements. They work well for a few elements of *any* size 111 // (i.e. sets of pointers)! 112 113 //------------------------------Set-------------------------------------------- 114 class Set : public ResourceObj { 115 public: 116 117 // Creates a new, empty set. 118 // DO NOT CONSTRUCT A Set. THIS IS AN ABSTRACT CLASS, FOR INHERITENCE ONLY Set(Arena * arena)119 Set(Arena *arena) : _set_arena(arena) {}; 120 121 // Creates a new set from an existing set 122 // DO NOT CONSTRUCT A Set. THIS IS AN ABSTRACT CLASS, FOR INHERITENCE ONLY Set(const Set &)123 Set(const Set &) {}; 124 125 // Set assignment; deep-copy guts 126 virtual Set &operator =(const Set &s)=0; 127 virtual Set &clone(void) const=0; 128 129 // Virtual destructor ~Set()130 virtual ~Set() {}; 131 132 // Add member to set 133 virtual Set &operator <<=(uint elem)=0; 134 // virtual Set operator << (uint elem); 135 136 // Delete member from set 137 virtual Set &operator >>=(uint elem)=0; 138 // virtual Set operator >> (uint elem); 139 140 // Membership test. Result is Zero (absent)/ Non-Zero (present) 141 virtual int operator [](uint elem) const=0; 142 143 // Intersect sets 144 virtual Set &operator &=(const Set &s)=0; 145 // virtual Set operator & (const Set &s) const; 146 147 // Union sets 148 virtual Set &operator |=(const Set &s)=0; 149 // virtual Set operator | (const Set &s) const; 150 151 // Difference sets 152 virtual Set &operator -=(const Set &s)=0; 153 // virtual Set operator - (const Set &s) const; 154 155 // Tests for equality. Result is Zero (false)/ Non-Zero (true) 156 virtual int operator ==(const Set &s) const=0; operator !=(const Set & s) const157 int operator !=(const Set &s) const { return !(*this == s); } 158 virtual int disjoint(const Set &s) const=0; 159 160 // Tests for strict subset. Result is Zero (false)/ Non-Zero (true) 161 virtual int operator < (const Set &s) const=0; operator >(const Set & s) const162 int operator > (const Set &s) const { return s < *this; } 163 164 // Tests for subset. Result is Zero (false)/ Non-Zero (true) 165 virtual int operator <=(const Set &s) const=0; operator >=(const Set & s) const166 int operator >=(const Set &s) const { return s <= *this; } 167 168 // Return any member of the Set. Undefined if the Set is empty. 169 virtual uint getelem(void) const=0; 170 171 // Clear all the elements in the Set 172 virtual void Clear(void)=0; 173 174 // Return the number of members in the Set 175 virtual uint Size(void) const=0; 176 177 // If an iterator follows a "Sort()" without any Set-modifying operations 178 // inbetween then the iterator will visit the elements in ascending order. 179 virtual void Sort(void)=0; 180 181 // Convert a set to printable string in an allocated buffer. 182 // The caller must deallocate the string. 183 virtual char *setstr(void) const; 184 185 // Print the Set on "stdout". Can be conveniently called in the debugger 186 void print() const; 187 188 // Parse text from the string into the Set. Return length parsed. 189 virtual int parse(const char *s); 190 191 // Convert a generic Set to a specific Set 192 /* Removed for MCC BUG 193 virtual operator const SparseSet* (void) const; 194 virtual operator const VectorSet* (void) const; 195 virtual operator const ListSet * (void) const; 196 virtual operator const CoSet * (void) const; */ 197 virtual const SparseSet *asSparseSet(void) const; 198 virtual const VectorSet *asVectorSet(void) const; 199 virtual const ListSet *asListSet (void) const; 200 virtual const CoSet *asCoSet (void) const; 201 202 // Hash the set. Sets of different types but identical elements will NOT 203 // hash the same. Same set type, same elements WILL hash the same. 204 virtual int hash() const = 0; 205 206 protected: 207 friend class SetI; 208 friend class CoSet; 209 virtual class SetI_ *iterate(uint&) const=0; 210 211 // Need storeage for the set 212 Arena *_set_arena; 213 }; 214 typedef Set&((*Set_Constructor)(Arena *arena)); 215 extern Set &ListSet_Construct(Arena *arena); 216 extern Set &VectorSet_Construct(Arena *arena); 217 extern Set &SparseSet_Construct(Arena *arena); 218 219 //------------------------------Iteration-------------------------------------- 220 // Loop thru all elements of the set, setting "elem" to the element numbers 221 // in random order. Inserted or deleted elements during this operation may 222 // or may not be iterated over; untouched elements will be affected once. 223 224 // Usage: for( SetI i(s); i.test(); i++ ) { body = i.elem; } ...OR... 225 // for( i.reset(s); i.test(); i++ ) { body = i.elem; } 226 227 class SetI_ : public ResourceObj { 228 protected: 229 friend class SetI; 230 virtual ~SetI_(); 231 virtual uint next(void)=0; 232 virtual int test(void)=0; 233 }; 234 235 class SetI { 236 protected: 237 SetI_ *impl; 238 public: 239 uint elem; // The publically accessible element 240 SetI(const Set * s)241 SetI( const Set *s ) { impl = s->iterate(elem); } ~SetI()242 ~SetI() { delete impl; } reset(const Set * s)243 void reset( const Set *s ) { delete impl; impl = s->iterate(elem); } operator ++(void)244 void operator ++(void) { elem = impl->next(); } test(void)245 int test(void) { return impl->test(); } 246 }; 247 248 #endif // SHARE_VM_LIBADT_SET_HPP 249