1 /* 2 * Copyright (c) 1997, 2012, 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_MEMORY_ALLOCATION_HPP 26 #define SHARE_VM_MEMORY_ALLOCATION_HPP 27 28 #include "runtime/globals.hpp" 29 #include "utilities/globalDefinitions.hpp" 30 #include "utilities/macros.hpp" 31 #ifdef COMPILER1 32 #include "c1/c1_globals.hpp" 33 #endif 34 #ifdef COMPILER2 35 #include "opto/c2_globals.hpp" 36 #endif 37 38 #include <new> 39 40 #define ARENA_ALIGN_M1 (((size_t)(ARENA_AMALLOC_ALIGNMENT)) - 1) 41 #define ARENA_ALIGN_MASK (~((size_t)ARENA_ALIGN_M1)) 42 #define ARENA_ALIGN(x) ((((size_t)(x)) + ARENA_ALIGN_M1) & ARENA_ALIGN_MASK) 43 44 45 // noinline attribute 46 #ifdef _WINDOWS 47 #define _NOINLINE_ __declspec(noinline) 48 #else 49 #if __GNUC__ < 3 // gcc 2.x does not support noinline attribute 50 #define _NOINLINE_ 51 #else 52 #define _NOINLINE_ __attribute__ ((noinline)) 53 #endif 54 #endif 55 56 class AllocFailStrategy { 57 public: 58 enum AllocFailEnum { EXIT_OOM, RETURN_NULL }; 59 }; 60 typedef AllocFailStrategy::AllocFailEnum AllocFailType; 61 62 // All classes in the virtual machine must be subclassed 63 // by one of the following allocation classes: 64 // 65 // For objects allocated in the resource area (see resourceArea.hpp). 66 // - ResourceObj 67 // 68 // For objects allocated in the C-heap (managed by: free & malloc). 69 // - CHeapObj 70 // 71 // For objects allocated on the stack. 72 // - StackObj 73 // 74 // For embedded objects. 75 // - ValueObj 76 // 77 // For classes used as name spaces. 78 // - AllStatic 79 // 80 // For classes in Metaspace (class data) 81 // - MetaspaceObj 82 // 83 // The printable subclasses are used for debugging and define virtual 84 // member functions for printing. Classes that avoid allocating the 85 // vtbl entries in the objects should therefore not be the printable 86 // subclasses. 87 // 88 // The following macros and function should be used to allocate memory 89 // directly in the resource area or in the C-heap: 90 // 91 // NEW_RESOURCE_ARRAY(type,size) 92 // NEW_RESOURCE_OBJ(type) 93 // NEW_C_HEAP_ARRAY(type,size) 94 // NEW_C_HEAP_OBJ(type) 95 // char* AllocateHeap(size_t size, const char* name); 96 // void FreeHeap(void* p); 97 // 98 // C-heap allocation can be traced using +PrintHeapAllocation. 99 // malloc and free should therefore never called directly. 100 101 // Base class for objects allocated in the C-heap. 102 103 // In non product mode we introduce a super class for all allocation classes 104 // that supports printing. 105 // We avoid the superclass in product mode since some C++ compilers add 106 // a word overhead for empty super classes. 107 108 #ifdef PRODUCT 109 #define ALLOCATION_SUPER_CLASS_SPEC 110 #else 111 #define ALLOCATION_SUPER_CLASS_SPEC : public AllocatedObj 112 class AllocatedObj { 113 public: 114 // Printing support 115 void print() const; 116 void print_value() const; 117 118 virtual void print_on(outputStream* st) const; 119 virtual void print_value_on(outputStream* st) const; 120 }; 121 #endif 122 123 124 /* 125 * MemoryType bitmap layout: 126 * | 16 15 14 13 12 11 10 09 | 08 07 06 05 | 04 03 02 01 | 127 * | memory type | object | reserved | 128 * | | type | | 129 */ 130 enum MemoryType { 131 // Memory type by sub systems. It occupies lower byte. 132 mtNone = 0x0000, // undefined 133 mtClass = 0x0100, // memory class for Java classes 134 mtThread = 0x0200, // memory for thread objects 135 mtThreadStack = 0x0300, 136 mtCode = 0x0400, // memory for generated code 137 mtGC = 0x0500, // memory for GC 138 mtCompiler = 0x0600, // memory for compiler 139 mtInternal = 0x0700, // memory used by VM, but does not belong to 140 // any of above categories, and not used for 141 // native memory tracking 142 mtOther = 0x0800, // memory not used by VM 143 mtSymbol = 0x0900, // symbol 144 mtNMT = 0x0A00, // memory used by native memory tracking 145 mtChunk = 0x0B00, // chunk that holds content of arenas 146 mtJavaHeap = 0x0C00, // Java heap 147 mtClassShared = 0x0D00, // class data sharing 148 mtTest = 0x0E00, // Test type for verifying NMT 149 mt_number_of_types = 0x000E, // number of memory types (mtDontTrack 150 // is not included as validate type) 151 mtDontTrack = 0x0F00, // memory we do not or cannot track 152 mt_masks = 0x7F00, 153 154 // object type mask 155 otArena = 0x0010, // an arena object 156 otNMTRecorder = 0x0020, // memory recorder object 157 ot_masks = 0x00F0 158 }; 159 160 #define IS_MEMORY_TYPE(flags, type) ((flags & mt_masks) == type) 161 #define HAS_VALID_MEMORY_TYPE(flags)((flags & mt_masks) != mtNone) 162 #define FLAGS_TO_MEMORY_TYPE(flags) (flags & mt_masks) 163 164 #define IS_ARENA_OBJ(flags) ((flags & ot_masks) == otArena) 165 #define IS_NMT_RECORDER(flags) ((flags & ot_masks) == otNMTRecorder) 166 #define NMT_CAN_TRACK(flags) (!IS_NMT_RECORDER(flags) && !(IS_MEMORY_TYPE(flags, mtDontTrack))) 167 168 typedef unsigned short MEMFLAGS; 169 170 #if INCLUDE_NMT 171 172 extern bool NMT_track_callsite; 173 174 #else 175 176 const bool NMT_track_callsite = false; 177 178 #endif // INCLUDE_NMT 179 180 // debug build does not inline 181 #if defined(_DEBUG_) 182 #define CURRENT_PC (NMT_track_callsite ? os::get_caller_pc(1) : 0) 183 #define CALLER_PC (NMT_track_callsite ? os::get_caller_pc(2) : 0) 184 #define CALLER_CALLER_PC (NMT_track_callsite ? os::get_caller_pc(3) : 0) 185 #else 186 #define CURRENT_PC (NMT_track_callsite? os::get_caller_pc(0) : 0) 187 #define CALLER_PC (NMT_track_callsite ? os::get_caller_pc(1) : 0) 188 #define CALLER_CALLER_PC (NMT_track_callsite ? os::get_caller_pc(2) : 0) 189 #endif 190 191 192 193 template <MEMFLAGS F> class CHeapObj ALLOCATION_SUPER_CLASS_SPEC { 194 public: 195 _NOINLINE_ void* operator new(size_t size, address caller_pc = 0); 196 _NOINLINE_ void* operator new (size_t size, const std::nothrow_t& nothrow_constant, 197 address caller_pc = 0); 198 199 void operator delete(void* p); 200 }; 201 202 // Base class for objects allocated on the stack only. 203 // Calling new or delete will result in fatal error. 204 205 class StackObj ALLOCATION_SUPER_CLASS_SPEC { 206 private: 207 void* operator new(size_t size); 208 void operator delete(void* p); 209 }; 210 211 // Base class for objects used as value objects. 212 // Calling new or delete will result in fatal error. 213 // 214 // Portability note: Certain compilers (e.g. gcc) will 215 // always make classes bigger if it has a superclass, even 216 // if the superclass does not have any virtual methods or 217 // instance fields. The HotSpot implementation relies on this 218 // not to happen. So never make a ValueObj class a direct subclass 219 // of this object, but use the VALUE_OBJ_CLASS_SPEC class instead, e.g., 220 // like this: 221 // 222 // class A VALUE_OBJ_CLASS_SPEC { 223 // ... 224 // } 225 // 226 // With gcc and possible other compilers the VALUE_OBJ_CLASS_SPEC can 227 // be defined as a an empty string "". 228 // 229 class _ValueObj { 230 private: 231 void* operator new(size_t size); 232 void operator delete(void* p); 233 }; 234 235 236 // Base class for objects stored in Metaspace. 237 // Calling delete will result in fatal error. 238 // 239 // Do not inherit from something with a vptr because this class does 240 // not introduce one. This class is used to allocate both shared read-only 241 // and shared read-write classes. 242 // 243 244 class ClassLoaderData; 245 246 class MetaspaceObj { 247 public: 248 bool is_metadata() const; 249 bool is_metaspace_object() const; // more specific test but slower 250 bool is_shared() const; 251 void print_address_on(outputStream* st) const; // nonvirtual address printing 252 253 void* operator new(size_t size, ClassLoaderData* loader_data, 254 size_t word_size, bool read_only, Thread* thread); 255 // can't use TRAPS from this header file. 256 void operator delete(void* p) { ShouldNotCallThis(); } 257 }; 258 259 // Base class for classes that constitute name spaces. 260 261 class AllStatic { 262 public: 263 AllStatic() { ShouldNotCallThis(); } 264 ~AllStatic() { ShouldNotCallThis(); } 265 }; 266 267 268 //------------------------------Chunk------------------------------------------ 269 // Linked list of raw memory chunks 270 class Chunk: CHeapObj<mtChunk> { 271 friend class VMStructs; 272 273 protected: 274 Chunk* _next; // Next Chunk in list 275 const size_t _len; // Size of this Chunk 276 public: 277 void* operator new(size_t size, size_t length); 278 void operator delete(void* p); 279 Chunk(size_t length); 280 281 enum { 282 // default sizes; make them slightly smaller than 2**k to guard against 283 // buddy-system style malloc implementations 284 #ifdef _LP64 285 slack = 40, // [RGV] Not sure if this is right, but make it 286 // a multiple of 8. 287 #else 288 slack = 20, // suspected sizeof(Chunk) + internal malloc headers 289 #endif 290 291 init_size = 1*K - slack, // Size of first chunk 292 medium_size= 10*K - slack, // Size of medium-sized chunk 293 size = 32*K - slack, // Default size of an Arena chunk (following the first) 294 non_pool_size = init_size + 32 // An initial size which is not one of above 295 }; 296 297 void chop(); // Chop this chunk 298 void next_chop(); // Chop next chunk 299 static size_t aligned_overhead_size(void) { return ARENA_ALIGN(sizeof(Chunk)); } 300 static size_t aligned_overhead_size(size_t byte_size) { return ARENA_ALIGN(byte_size); } 301 302 size_t length() const { return _len; } 303 Chunk* next() const { return _next; } 304 void set_next(Chunk* n) { _next = n; } 305 // Boundaries of data area (possibly unused) 306 char* bottom() const { return ((char*) this) + aligned_overhead_size(); } 307 char* top() const { return bottom() + _len; } 308 bool contains(char* p) const { return bottom() <= p && p <= top(); } 309 310 // Start the chunk_pool cleaner task 311 static void start_chunk_pool_cleaner_task(); 312 313 static void clean_chunk_pool(); 314 }; 315 316 //------------------------------Arena------------------------------------------ 317 // Fast allocation of memory 318 class Arena : public CHeapObj<mtNone|otArena> { 319 protected: 320 friend class ResourceMark; 321 friend class HandleMark; 322 friend class NoHandleMark; 323 friend class VMStructs; 324 325 Chunk *_first; // First chunk 326 Chunk *_chunk; // current chunk 327 char *_hwm, *_max; // High water mark and max in current chunk 328 // Get a new Chunk of at least size x 329 void* grow(size_t x, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM); 330 size_t _size_in_bytes; // Size of arena (used for native memory tracking) 331 332 NOT_PRODUCT(static julong _bytes_allocated;) // total #bytes allocated since start 333 friend class AllocStats; 334 debug_only(void* malloc(size_t size);) 335 debug_only(void* internal_malloc_4(size_t x);) 336 NOT_PRODUCT(void inc_bytes_allocated(size_t x);) 337 338 void signal_out_of_memory(size_t request, const char* whence) const; 339 340 void check_for_overflow(size_t request, const char* whence) const { 341 if (UINTPTR_MAX - request < (uintptr_t)_hwm) { 342 signal_out_of_memory(request, whence); 343 } 344 } 345 346 public: 347 Arena(); 348 Arena(size_t init_size); 349 ~Arena(); 350 void destruct_contents(); 351 char* hwm() const { return _hwm; } 352 353 // new operators 354 void* operator new (size_t size); 355 void* operator new (size_t size, const std::nothrow_t& nothrow_constant); 356 357 // dynamic memory type tagging 358 void* operator new(size_t size, MEMFLAGS flags); 359 void* operator new(size_t size, const std::nothrow_t& nothrow_constant, MEMFLAGS flags); 360 void operator delete(void* p); 361 362 // Fast allocate in the arena. Common case is: pointer test + increment. 363 void* Amalloc(size_t x, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM) { 364 assert(is_power_of_2(ARENA_AMALLOC_ALIGNMENT) , "should be a power of 2"); 365 x = ARENA_ALIGN(x); 366 debug_only(if (UseMallocOnly) return malloc(x);) 367 check_for_overflow(x, "Arena::Amalloc"); 368 NOT_PRODUCT(inc_bytes_allocated(x);) 369 if (_hwm + x > _max) { 370 return grow(x, alloc_failmode); 371 } else { 372 char *old = _hwm; 373 _hwm += x; 374 return old; 375 } 376 } 377 // Further assume size is padded out to words 378 void *Amalloc_4(size_t x, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM) { 379 assert( (x&(sizeof(char*)-1)) == 0, "misaligned size" ); 380 debug_only(if (UseMallocOnly) return malloc(x);) 381 check_for_overflow(x, "Arena::Amalloc_4"); 382 NOT_PRODUCT(inc_bytes_allocated(x);) 383 if (_hwm + x > _max) { 384 return grow(x, alloc_failmode); 385 } else { 386 char *old = _hwm; 387 _hwm += x; 388 return old; 389 } 390 } 391 392 // Allocate with 'double' alignment. It is 8 bytes on sparc. 393 // In other cases Amalloc_D() should be the same as Amalloc_4(). 394 void* Amalloc_D(size_t x, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM) { 395 assert( (x&(sizeof(char*)-1)) == 0, "misaligned size" ); 396 debug_only(if (UseMallocOnly) return malloc(x);) 397 #if defined(SPARC) && !defined(_LP64) 398 #define DALIGN_M1 7 399 size_t delta = (((size_t)_hwm + DALIGN_M1) & ~DALIGN_M1) - (size_t)_hwm; 400 x += delta; 401 #endif 402 check_for_overflow(x, "Arena::Amalloc_D"); 403 NOT_PRODUCT(inc_bytes_allocated(x);) 404 if (_hwm + x > _max) { 405 return grow(x, alloc_failmode); // grow() returns a result aligned >= 8 bytes. 406 } else { 407 char *old = _hwm; 408 _hwm += x; 409 #if defined(SPARC) && !defined(_LP64) 410 old += delta; // align to 8-bytes 411 #endif 412 return old; 413 } 414 } 415 416 // Fast delete in area. Common case is: NOP (except for storage reclaimed) 417 void Afree(void *ptr, size_t size) { 418 #ifdef ASSERT 419 if (ZapResourceArea) memset(ptr, badResourceValue, size); // zap freed memory 420 if (UseMallocOnly) return; 421 #endif 422 if (((char*)ptr) + size == _hwm) _hwm = (char*)ptr; 423 } 424 425 void *Arealloc( void *old_ptr, size_t old_size, size_t new_size, 426 AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM); 427 428 // Move contents of this arena into an empty arena 429 Arena *move_contents(Arena *empty_arena); 430 431 // Determine if pointer belongs to this Arena or not. 432 bool contains( const void *ptr ) const; 433 434 // Total of all chunks in use (not thread-safe) 435 size_t used() const; 436 437 // Total # of bytes used 438 size_t size_in_bytes() const { return _size_in_bytes; }; 439 void set_size_in_bytes(size_t size); 440 441 static void free_malloced_objects(Chunk* chunk, char* hwm, char* max, char* hwm2) PRODUCT_RETURN; 442 static void free_all(char** start, char** end) PRODUCT_RETURN; 443 444 // how many arena instances 445 NOT_PRODUCT(static volatile jint _instance_count;) 446 private: 447 // Reset this Arena to empty, access will trigger grow if necessary 448 void reset(void) { 449 _first = _chunk = NULL; 450 _hwm = _max = NULL; 451 set_size_in_bytes(0); 452 } 453 }; 454 455 // One of the following macros must be used when allocating 456 // an array or object from an arena 457 #define NEW_ARENA_ARRAY(arena, type, size) \ 458 (type*) (arena)->Amalloc((size) * sizeof(type)) 459 460 #define REALLOC_ARENA_ARRAY(arena, type, old, old_size, new_size) \ 461 (type*) (arena)->Arealloc((char*)(old), (old_size) * sizeof(type), \ 462 (new_size) * sizeof(type) ) 463 464 #define FREE_ARENA_ARRAY(arena, type, old, size) \ 465 (arena)->Afree((char*)(old), (size) * sizeof(type)) 466 467 #define NEW_ARENA_OBJ(arena, type) \ 468 NEW_ARENA_ARRAY(arena, type, 1) 469 470 471 //%note allocation_1 472 extern char* resource_allocate_bytes(size_t size, 473 AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM); 474 extern char* resource_allocate_bytes(Thread* thread, size_t size, 475 AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM); 476 extern char* resource_reallocate_bytes( char *old, size_t old_size, size_t new_size, 477 AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM); 478 extern void resource_free_bytes( char *old, size_t size ); 479 480 //---------------------------------------------------------------------- 481 // Base class for objects allocated in the resource area per default. 482 // Optionally, objects may be allocated on the C heap with 483 // new(ResourceObj::C_HEAP) Foo(...) or in an Arena with new (&arena) 484 // ResourceObj's can be allocated within other objects, but don't use 485 // new or delete (allocation_type is unknown). If new is used to allocate, 486 // use delete to deallocate. 487 class ResourceObj ALLOCATION_SUPER_CLASS_SPEC { 488 public: 489 enum allocation_type { STACK_OR_EMBEDDED = 0, RESOURCE_AREA, C_HEAP, ARENA, allocation_mask = 0x3 }; 490 static void set_allocation_type(address res, allocation_type type) NOT_DEBUG_RETURN; 491 #ifdef ASSERT 492 private: 493 // When this object is allocated on stack the new() operator is not 494 // called but garbage on stack may look like a valid allocation_type. 495 // Store negated 'this' pointer when new() is called to distinguish cases. 496 // Use second array's element for verification value to distinguish garbage. 497 uintptr_t _allocation_t[2]; 498 bool is_type_set() const; 499 public: 500 allocation_type get_allocation_type() const; 501 bool allocated_on_stack() const { return get_allocation_type() == STACK_OR_EMBEDDED; } 502 bool allocated_on_res_area() const { return get_allocation_type() == RESOURCE_AREA; } 503 bool allocated_on_C_heap() const { return get_allocation_type() == C_HEAP; } 504 bool allocated_on_arena() const { return get_allocation_type() == ARENA; } 505 ResourceObj(); // default construtor 506 ResourceObj(const ResourceObj& r); // default copy construtor 507 ResourceObj& operator=(const ResourceObj& r); // default copy assignment 508 ~ResourceObj(); 509 #endif // ASSERT 510 511 public: 512 void* operator new(size_t size, allocation_type type, MEMFLAGS flags); 513 void* operator new(size_t size, const std::nothrow_t& nothrow_constant, 514 allocation_type type, MEMFLAGS flags); 515 void* operator new(size_t size, Arena *arena) { 516 address res = (address)arena->Amalloc(size); 517 DEBUG_ONLY(set_allocation_type(res, ARENA);) 518 return res; 519 } 520 void* operator new(size_t size) { 521 address res = (address)resource_allocate_bytes(size); 522 DEBUG_ONLY(set_allocation_type(res, RESOURCE_AREA);) 523 return res; 524 } 525 526 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) { 527 address res = (address)resource_allocate_bytes(size, AllocFailStrategy::RETURN_NULL); 528 DEBUG_ONLY(if (res != NULL) set_allocation_type(res, RESOURCE_AREA);) 529 return res; 530 } 531 532 void operator delete(void* p); 533 }; 534 535 // One of the following macros must be used when allocating an array 536 // or object to determine whether it should reside in the C heap on in 537 // the resource area. 538 539 #define NEW_RESOURCE_ARRAY(type, size)\ 540 (type*) resource_allocate_bytes((size) * sizeof(type)) 541 542 #define NEW_RESOURCE_ARRAY_IN_THREAD(thread, type, size)\ 543 (type*) resource_allocate_bytes(thread, (size) * sizeof(type)) 544 545 #define REALLOC_RESOURCE_ARRAY(type, old, old_size, new_size)\ 546 (type*) resource_reallocate_bytes((char*)(old), (old_size) * sizeof(type), (new_size) * sizeof(type) ) 547 548 #define FREE_RESOURCE_ARRAY(type, old, size)\ 549 resource_free_bytes((char*)(old), (size) * sizeof(type)) 550 551 #define FREE_FAST(old)\ 552 /* nop */ 553 554 #define NEW_RESOURCE_OBJ(type)\ 555 NEW_RESOURCE_ARRAY(type, 1) 556 557 #define NEW_C_HEAP_ARRAY(type, size, memflags)\ 558 (type*) (AllocateHeap((size) * sizeof(type), memflags)) 559 560 #define REALLOC_C_HEAP_ARRAY(type, old, size, memflags)\ 561 (type*) (ReallocateHeap((char*)old, (size) * sizeof(type), memflags)) 562 563 #define FREE_C_HEAP_ARRAY(type,old,memflags) \ 564 FreeHeap((char*)(old), memflags) 565 566 #define NEW_C_HEAP_OBJ(type, memflags)\ 567 NEW_C_HEAP_ARRAY(type, 1, memflags) 568 569 570 #define NEW_C_HEAP_ARRAY2(type, size, memflags, pc)\ 571 (type*) (AllocateHeap((size) * sizeof(type), memflags, pc)) 572 573 #define REALLOC_C_HEAP_ARRAY2(type, old, size, memflags, pc)\ 574 (type*) (ReallocateHeap((char*)old, (size) * sizeof(type), memflags, pc)) 575 576 #define NEW_C_HEAP_OBJ2(type, memflags, pc)\ 577 NEW_C_HEAP_ARRAY2(type, 1, memflags, pc) 578 579 580 extern bool warn_new_operator; 581 582 // for statistics 583 #ifndef PRODUCT 584 class AllocStats : StackObj { 585 julong start_mallocs, start_frees; 586 julong start_malloc_bytes, start_mfree_bytes, start_res_bytes; 587 public: 588 AllocStats(); 589 590 julong num_mallocs(); // since creation of receiver 591 julong alloc_bytes(); 592 julong num_frees(); 593 julong free_bytes(); 594 julong resource_bytes(); 595 void print(); 596 }; 597 #endif 598 599 600 //------------------------------ReallocMark--------------------------------- 601 // Code which uses REALLOC_RESOURCE_ARRAY should check an associated 602 // ReallocMark, which is declared in the same scope as the reallocated 603 // pointer. Any operation that could __potentially__ cause a reallocation 604 // should check the ReallocMark. 605 class ReallocMark: public StackObj { 606 protected: 607 NOT_PRODUCT(int _nesting;) 608 609 public: 610 ReallocMark() PRODUCT_RETURN; 611 void check() PRODUCT_RETURN; 612 }; 613 614 #endif // SHARE_VM_MEMORY_ALLOCATION_HPP