1 /*
   2  * Copyright (c) 1997, 2013, 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_UTILITIES_GROWABLEARRAY_HPP
  26 #define SHARE_VM_UTILITIES_GROWABLEARRAY_HPP
  27 
  28 #include "memory/allocation.hpp"
  29 #include "memory/allocation.inline.hpp"
  30 #include "utilities/debug.hpp"
  31 #include "utilities/globalDefinitions.hpp"
  32 #include "utilities/top.hpp"
  33 
  34 // A growable array.
  35 
  36 /*************************************************************************/
  37 /*                                                                       */
  38 /*     WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING   */
  39 /*                                                                       */
  40 /* Should you use GrowableArrays to contain handles you must be certain  */
  41 /* the the GrowableArray does not outlive the HandleMark that contains   */
  42 /* the handles. Since GrowableArrays are typically resource allocated    */
  43 /* the following is an example of INCORRECT CODE,                        */
  44 /*                                                                       */
  45 /* ResourceMark rm;                                                      */
  46 /* GrowableArray<Handle>* arr = new GrowableArray<Handle>(size);         */
  47 /* if (blah) {                                                           */
  48 /*    while (...) {                                                      */
  49 /*      HandleMark hm;                                                   */
  50 /*      ...                                                              */
  51 /*      Handle h(THREAD, some_oop);                                      */
  52 /*      arr->append(h);                                                  */
  53 /*    }                                                                  */
  54 /* }                                                                     */
  55 /* if (arr->length() != 0 ) {                                            */
  56 /*    oop bad_oop = arr->at(0)(); // Handle is BAD HERE.                 */
  57 /*    ...                                                                */
  58 /* }                                                                     */
  59 /*                                                                       */
  60 /* If the GrowableArrays you are creating is C_Heap allocated then it    */
  61 /* hould not old handles since the handles could trivially try and       */
  62 /* outlive their HandleMark. In some situations you might need to do     */
  63 /* this and it would be legal but be very careful and see if you can do  */
  64 /* the code in some other manner.                                        */
  65 /*                                                                       */
  66 /*************************************************************************/
  67 
  68 // To call default constructor the placement operator new() is used.
  69 // It should be empty (it only returns the passed void* pointer).
  70 // The definition of placement operator new(size_t, void*) in the <new>.
  71 
  72 #include <new>
  73 
  74 // Need the correct linkage to call qsort without warnings
  75 extern "C" {
  76   typedef int (*_sort_Fn)(const void *, const void *);
  77 }
  78 
  79 class GenericGrowableArray : public ResourceObj {
  80   friend class VMStructs;
  81 
  82  protected:
  83   int    _len;          // current length
  84   int    _max;          // maximum length
  85   Arena* _arena;        // Indicates where allocation occurs:
  86                         //   0 means default ResourceArea
  87                         //   1 means on C heap
  88                         //   otherwise, allocate in _arena
  89 
  90   MEMFLAGS   _memflags;   // memory type if allocation in C heap
  91 
  92 #ifdef ASSERT
  93   int    _nesting;      // resource area nesting at creation
  94   void   set_nesting();
  95   void   check_nesting();
  96 #else
  97 #define  set_nesting();
  98 #define  check_nesting();
  99 #endif
 100 
 101   // Where are we going to allocate memory?
 102   bool on_C_heap() { return _arena == (Arena*)1; }
 103   bool on_stack () { return _arena == NULL;      }
 104   bool on_arena () { return _arena >  (Arena*)1;  }
 105 
 106   // This GA will use the resource stack for storage if c_heap==false,
 107   // Else it will use the C heap.  Use clear_and_deallocate to avoid leaks.
 108   GenericGrowableArray(int initial_size, int initial_len, bool c_heap, MEMFLAGS flags = mtNone) {
 109     _len = initial_len;
 110     _max = initial_size;
 111     _memflags = flags;
 112 
 113     // memory type has to be specified for C heap allocation
 114     assert(!(c_heap && flags == mtNone), "memory type not specified for C heap object");
 115 
 116     assert(_len >= 0 && _len <= _max, "initial_len too big");
 117     _arena = (c_heap ? (Arena*)1 : NULL);
 118     set_nesting();
 119     assert(!on_C_heap() || allocated_on_C_heap(), "growable array must be on C heap if elements are");
 120     assert(!on_stack() ||
 121            (allocated_on_res_area() || allocated_on_stack()),
 122            "growable array must be on stack if elements are not on arena and not on C heap");
 123   }
 124 
 125   // This GA will use the given arena for storage.
 126   // Consider using new(arena) GrowableArray<T> to allocate the header.
 127   GenericGrowableArray(Arena* arena, int initial_size, int initial_len) {
 128     _len = initial_len;
 129     _max = initial_size;
 130     assert(_len >= 0 && _len <= _max, "initial_len too big");
 131     _arena = arena;
 132     _memflags = mtNone;
 133 
 134     assert(on_arena(), "arena has taken on reserved value 0 or 1");
 135     // Relax next assert to allow object allocation on resource area,
 136     // on stack or embedded into an other object.
 137     assert(allocated_on_arena() || allocated_on_stack(),
 138            "growable array must be on arena or on stack if elements are on arena");
 139   }
 140 
 141   void* raw_allocate(int elementSize);
 142 
 143   // some uses pass the Thread explicitly for speed (4990299 tuning)
 144   void* raw_allocate(Thread* thread, int elementSize) {
 145     assert(on_stack(), "fast ResourceObj path only");
 146     return (void*)resource_allocate_bytes(thread, elementSize * _max);
 147   }
 148 };
 149 
 150 template<class E> class GrowableArrayIterator;
 151 template<class E, class UnaryPredicate> class GrowableArrayFilterIterator;
 152 
 153 template<class E> class GrowableArray : public GenericGrowableArray {
 154   friend class VMStructs;
 155 
 156  private:
 157   E*     _data;         // data array
 158 
 159   void grow(int j);
 160   void raw_at_put_grow(int i, const E& p, const E& fill);
 161   void  clear_and_deallocate();
 162  public:
 163   GrowableArray(Thread* thread, int initial_size) : GenericGrowableArray(initial_size, 0, false) {
 164     _data = (E*)raw_allocate(thread, sizeof(E));
 165     for (int i = 0; i < _max; i++) ::new ((void*)&_data[i]) E();
 166   }
 167 
 168   GrowableArray(int initial_size, bool C_heap = false, MEMFLAGS F = mtInternal)
 169     : GenericGrowableArray(initial_size, 0, C_heap, F) {
 170     _data = (E*)raw_allocate(sizeof(E));




 171     for (int i = 0; i < _max; i++) ::new ((void*)&_data[i]) E();
 172   }
 173 
 174   GrowableArray(int initial_size, int initial_len, const E& filler, bool C_heap = false, MEMFLAGS memflags = mtInternal)
 175     : GenericGrowableArray(initial_size, initial_len, C_heap, memflags) {
 176     _data = (E*)raw_allocate(sizeof(E));
 177     int i = 0;
 178     for (; i < _len; i++) ::new ((void*)&_data[i]) E(filler);
 179     for (; i < _max; i++) ::new ((void*)&_data[i]) E();
 180   }
 181 
 182   GrowableArray(Arena* arena, int initial_size, int initial_len, const E& filler) : GenericGrowableArray(arena, initial_size, initial_len) {
 183     _data = (E*)raw_allocate(sizeof(E));
 184     int i = 0;
 185     for (; i < _len; i++) ::new ((void*)&_data[i]) E(filler);
 186     for (; i < _max; i++) ::new ((void*)&_data[i]) E();
 187   }
 188 
 189   GrowableArray() : GenericGrowableArray(2, 0, false) {
 190     _data = (E*)raw_allocate(sizeof(E));
 191     ::new ((void*)&_data[0]) E();
 192     ::new ((void*)&_data[1]) E();
 193   }
 194 
 195                                 // Does nothing for resource and arena objects
 196   ~GrowableArray()              { if (on_C_heap()) clear_and_deallocate(); }
 197 
 198   void  clear()                 { _len = 0; }
 199   int   length() const          { return _len; }
 200   int   max_length() const      { return _max; }
 201   void  trunc_to(int l)         { assert(l <= _len,"cannot increase length"); _len = l; }
 202   bool  is_empty() const        { return _len == 0; }
 203   bool  is_nonempty() const     { return _len != 0; }
 204   bool  is_full() const         { return _len == _max; }
 205   DEBUG_ONLY(E* data_addr() const      { return _data; })
 206 
 207   void print();
 208 
 209   int append(const E& elem) {
 210     check_nesting();
 211     if (_len == _max) grow(_len);
 212     int idx = _len++;
 213     _data[idx] = elem;
 214     return idx;
 215   }
 216 
 217   bool append_if_missing(const E& elem) {
 218     // Returns TRUE if elem is added.
 219     bool missed = !contains(elem);
 220     if (missed) append(elem);
 221     return missed;
 222   }
 223 
 224   E& at(int i) {
 225     assert(0 <= i && i < _len, "illegal index");
 226     return _data[i];
 227   }
 228 
 229   E const& at(int i) const {
 230     assert(0 <= i && i < _len, "illegal index");
 231     return _data[i];
 232   }
 233 
 234   E* adr_at(int i) const {
 235     assert(0 <= i && i < _len, "illegal index");
 236     return &_data[i];
 237   }
 238 
 239   E first() const {
 240     assert(_len > 0, "empty list");
 241     return _data[0];
 242   }
 243 
 244   E top() const {
 245     assert(_len > 0, "empty list");
 246     return _data[_len-1];
 247   }
 248 
 249   GrowableArrayIterator<E> begin() const {
 250     return GrowableArrayIterator<E>(this, 0);
 251   }
 252 
 253   GrowableArrayIterator<E> end() const {
 254     return GrowableArrayIterator<E>(this, length());
 255   }
 256 
 257   void push(const E& elem) { append(elem); }
 258 
 259   E pop() {
 260     assert(_len > 0, "empty list");
 261     return _data[--_len];
 262   }
 263 
 264   void at_put(int i, const E& elem) {
 265     assert(0 <= i && i < _len, "illegal index");
 266     _data[i] = elem;
 267   }
 268 
 269   E at_grow(int i, const E& fill = E()) {
 270     assert(0 <= i, "negative index");
 271     check_nesting();
 272     if (i >= _len) {
 273       if (i >= _max) grow(i);
 274       for (int j = _len; j <= i; j++)
 275         _data[j] = fill;
 276       _len = i+1;
 277     }
 278     return _data[i];
 279   }
 280 
 281   void at_put_grow(int i, const E& elem, const E& fill = E()) {
 282     assert(0 <= i, "negative index");
 283     check_nesting();
 284     raw_at_put_grow(i, elem, fill);
 285   }
 286 
 287   bool contains(const E& elem) const {
 288     for (int i = 0; i < _len; i++) {
 289       if (_data[i] == elem) return true;
 290     }
 291     return false;
 292   }
 293 
 294   int  find(const E& elem) const {
 295     for (int i = 0; i < _len; i++) {
 296       if (_data[i] == elem) return i;
 297     }
 298     return -1;
 299   }
 300 
 301   int  find_from_end(const E& elem) const {
 302     for (int i = _len-1; i >= 0; i--) {
 303       if (_data[i] == elem) return i;
 304     }
 305     return -1;
 306   }
 307 
 308   int  find(void* token, bool f(void*, E)) const {
 309     for (int i = 0; i < _len; i++) {
 310       if (f(token, _data[i])) return i;
 311     }
 312     return -1;
 313   }
 314 
 315   int  find_from_end(void* token, bool f(void*, E)) const {
 316     // start at the end of the array
 317     for (int i = _len-1; i >= 0; i--) {
 318       if (f(token, _data[i])) return i;
 319     }
 320     return -1;
 321   }
 322 
 323   void remove(const E& elem) {
 324     for (int i = 0; i < _len; i++) {
 325       if (_data[i] == elem) {
 326         for (int j = i + 1; j < _len; j++) _data[j-1] = _data[j];
 327         _len--;
 328         return;
 329       }
 330     }
 331     ShouldNotReachHere();
 332   }
 333 
 334   // The order is preserved.
 335   void remove_at(int index) {
 336     assert(0 <= index && index < _len, "illegal index");
 337     for (int j = index + 1; j < _len; j++) _data[j-1] = _data[j];
 338     _len--;
 339   }
 340 
 341   // The order is changed.
 342   void delete_at(int index) {
 343     assert(0 <= index && index < _len, "illegal index");
 344     if (index < --_len) {
 345       // Replace removed element with last one.
 346       _data[index] = _data[_len];
 347     }
 348   }
 349 
 350   // inserts the given element before the element at index i
 351   void insert_before(const int idx, const E& elem) {
 352     assert(0 <= idx && idx <= _len, "illegal index");
 353     check_nesting();
 354     if (_len == _max) grow(_len);
 355     for (int j = _len - 1; j >= idx; j--) {
 356       _data[j + 1] = _data[j];
 357     }
 358     _len++;
 359     _data[idx] = elem;
 360   }
 361 
 362   void appendAll(const GrowableArray<E>* l) {
 363     for (int i = 0; i < l->_len; i++) {
 364       raw_at_put_grow(_len, l->_data[i], E());
 365     }
 366   }
 367 
 368   void sort(int f(E*,E*)) {
 369     qsort(_data, length(), sizeof(E), (_sort_Fn)f);
 370   }
 371   // sort by fixed-stride sub arrays:
 372   void sort(int f(E*,E*), int stride) {
 373     qsort(_data, length() / stride, sizeof(E) * stride, (_sort_Fn)f);
 374   }


































 375 };
 376 
 377 // Global GrowableArray methods (one instance in the library per each 'E' type).
 378 
 379 template<class E> void GrowableArray<E>::grow(int j) {
 380     // grow the array by doubling its size (amortized growth)
 381     int old_max = _max;
 382     if (_max == 0) _max = 1; // prevent endless loop
 383     while (j >= _max) _max = _max*2;
 384     // j < _max
 385     E* newData = (E*)raw_allocate(sizeof(E));
 386     int i = 0;
 387     for (     ; i < _len; i++) ::new ((void*)&newData[i]) E(_data[i]);




 388     for (     ; i < _max; i++) ::new ((void*)&newData[i]) E();
 389     for (i = 0; i < old_max; i++) _data[i].~E();
 390     if (on_C_heap() && _data != NULL) {
 391       FreeHeap(_data);
 392     }
 393     _data = newData;
 394 }
 395 
 396 template<class E> void GrowableArray<E>::raw_at_put_grow(int i, const E& p, const E& fill) {
 397     if (i >= _len) {
 398       if (i >= _max) grow(i);
 399       for (int j = _len; j < i; j++)
 400         _data[j] = fill;
 401       _len = i+1;
 402     }
 403     _data[i] = p;
 404 }
 405 
 406 // This function clears and deallocate the data in the growable array that
 407 // has been allocated on the C heap.  It's not public - called by the
 408 // destructor.
 409 template<class E> void GrowableArray<E>::clear_and_deallocate() {
 410     assert(on_C_heap(),
 411            "clear_and_deallocate should only be called when on C heap");
 412     clear();
 413     if (_data != NULL) {
 414       for (int i = 0; i < _max; i++) _data[i].~E();
 415       FreeHeap(_data);
 416       _data = NULL;
 417     }
 418 }
 419 
 420 template<class E> void GrowableArray<E>::print() {
 421     tty->print("Growable Array " INTPTR_FORMAT, this);
 422     tty->print(": length %ld (_max %ld) { ", _len, _max);
 423     for (int i = 0; i < _len; i++) tty->print(INTPTR_FORMAT " ", *(intptr_t*)&(_data[i]));
 424     tty->print("}\n");
 425 }
 426 
 427 // Custom STL-style iterator to iterate over GrowableArrays
 428 // It is constructed by invoking GrowableArray::begin() and GrowableArray::end()
 429 template<class E> class GrowableArrayIterator : public StackObj {
 430   friend class GrowableArray<E>;
 431   template<class F, class UnaryPredicate> friend class GrowableArrayFilterIterator;
 432 
 433  private:
 434   const GrowableArray<E>* _array; // GrowableArray we iterate over
 435   int _position;                  // The current position in the GrowableArray
 436 
 437   // Private constructor used in GrowableArray::begin() and GrowableArray::end()
 438   GrowableArrayIterator(const GrowableArray<E>* array, int position) : _array(array), _position(position) {
 439     assert(0 <= position && position <= _array->length(), "illegal position");
 440   }
 441 
 442  public:
 443   GrowableArrayIterator<E>& operator++()  { ++_position; return *this; }
 444   E operator*()                           { return _array->at(_position); }
 445 
 446   bool operator==(const GrowableArrayIterator<E>& rhs)  {
 447     assert(_array == rhs._array, "iterator belongs to different array");
 448     return _position == rhs._position;
 449   }
 450 
 451   bool operator!=(const GrowableArrayIterator<E>& rhs)  {
 452     assert(_array == rhs._array, "iterator belongs to different array");
 453     return _position != rhs._position;
 454   }
 455 };
 456 
 457 // Custom STL-style iterator to iterate over elements of a GrowableArray that satisfy a given predicate
 458 template<class E, class UnaryPredicate> class GrowableArrayFilterIterator : public StackObj {
 459   friend class GrowableArray<E>;
 460 
 461  private:
 462   const GrowableArray<E>* _array;   // GrowableArray we iterate over
 463   int _position;                    // Current position in the GrowableArray
 464   UnaryPredicate _predicate;        // Unary predicate the elements of the GrowableArray should satisfy
 465 
 466  public:
 467   GrowableArrayFilterIterator(const GrowableArrayIterator<E>& begin, UnaryPredicate filter_predicate)
 468    : _array(begin._array), _position(begin._position), _predicate(filter_predicate) {
 469     // Advance to first element satisfying the predicate
 470     while(_position != _array->length() && !_predicate(_array->at(_position))) {
 471       ++_position;
 472     }
 473   }
 474 
 475   GrowableArrayFilterIterator<E, UnaryPredicate>& operator++() {
 476     do {
 477       // Advance to next element satisfying the predicate
 478       ++_position;
 479     } while(_position != _array->length() && !_predicate(_array->at(_position)));
 480     return *this;
 481   }
 482 
 483   E operator*()   { return _array->at(_position); }
 484 
 485   bool operator==(const GrowableArrayIterator<E>& rhs)  {
 486     assert(_array == rhs._array, "iterator belongs to different array");
 487     return _position == rhs._position;
 488   }
 489 
 490   bool operator!=(const GrowableArrayIterator<E>& rhs)  {
 491     assert(_array == rhs._array, "iterator belongs to different array");
 492     return _position != rhs._position;
 493   }
 494 
 495   bool operator==(const GrowableArrayFilterIterator<E, UnaryPredicate>& rhs)  {
 496     assert(_array == rhs._array, "iterator belongs to different array");
 497     return _position == rhs._position;
 498   }
 499 
 500   bool operator!=(const GrowableArrayFilterIterator<E, UnaryPredicate>& rhs)  {
 501     assert(_array == rhs._array, "iterator belongs to different array");
 502     return _position != rhs._position;
 503   }
 504 };
 505 
 506 #endif // SHARE_VM_UTILITIES_GROWABLEARRAY_HPP
--- EOF ---