Thu, 21 Nov 2013 12:30:35 -0800
Merge
1 /*
2 * Copyright (c) 2001, 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 */
25 #include "precompiled.hpp"
26 #include "classfile/systemDictionary.hpp"
27 #include "gc_implementation/shared/gcHeapSummary.hpp"
28 #include "gc_implementation/shared/gcTrace.hpp"
29 #include "gc_implementation/shared/gcTraceTime.hpp"
30 #include "gc_implementation/shared/gcWhen.hpp"
31 #include "gc_implementation/shared/vmGCOperations.hpp"
32 #include "gc_interface/allocTracer.hpp"
33 #include "gc_interface/collectedHeap.hpp"
34 #include "gc_interface/collectedHeap.inline.hpp"
35 #include "memory/metaspace.hpp"
36 #include "oops/oop.inline.hpp"
37 #include "oops/instanceMirrorKlass.hpp"
38 #include "runtime/init.hpp"
39 #include "runtime/thread.inline.hpp"
40 #include "services/heapDumper.hpp"
43 #ifdef ASSERT
44 int CollectedHeap::_fire_out_of_memory_count = 0;
45 #endif
47 size_t CollectedHeap::_filler_array_max_size = 0;
49 template <>
50 void EventLogBase<GCMessage>::print(outputStream* st, GCMessage& m) {
51 st->print_cr("GC heap %s", m.is_before ? "before" : "after");
52 st->print_raw(m);
53 }
55 void GCHeapLog::log_heap(bool before) {
56 if (!should_log()) {
57 return;
58 }
60 double timestamp = fetch_timestamp();
61 MutexLockerEx ml(&_mutex, Mutex::_no_safepoint_check_flag);
62 int index = compute_log_index();
63 _records[index].thread = NULL; // Its the GC thread so it's not that interesting.
64 _records[index].timestamp = timestamp;
65 _records[index].data.is_before = before;
66 stringStream st(_records[index].data.buffer(), _records[index].data.size());
67 if (before) {
68 Universe::print_heap_before_gc(&st, true);
69 } else {
70 Universe::print_heap_after_gc(&st, true);
71 }
72 }
74 VirtualSpaceSummary CollectedHeap::create_heap_space_summary() {
75 size_t capacity_in_words = capacity() / HeapWordSize;
77 return VirtualSpaceSummary(
78 reserved_region().start(), reserved_region().start() + capacity_in_words, reserved_region().end());
79 }
81 GCHeapSummary CollectedHeap::create_heap_summary() {
82 VirtualSpaceSummary heap_space = create_heap_space_summary();
83 return GCHeapSummary(heap_space, used());
84 }
86 MetaspaceSummary CollectedHeap::create_metaspace_summary() {
87 const MetaspaceSizes meta_space(
88 MetaspaceAux::allocated_capacity_bytes(),
89 MetaspaceAux::allocated_used_bytes(),
90 MetaspaceAux::reserved_bytes());
91 const MetaspaceSizes data_space(
92 MetaspaceAux::allocated_capacity_bytes(Metaspace::NonClassType),
93 MetaspaceAux::allocated_used_bytes(Metaspace::NonClassType),
94 MetaspaceAux::reserved_bytes(Metaspace::NonClassType));
95 const MetaspaceSizes class_space(
96 MetaspaceAux::allocated_capacity_bytes(Metaspace::ClassType),
97 MetaspaceAux::allocated_used_bytes(Metaspace::ClassType),
98 MetaspaceAux::reserved_bytes(Metaspace::ClassType));
100 return MetaspaceSummary(meta_space, data_space, class_space);
101 }
103 void CollectedHeap::print_heap_before_gc() {
104 if (PrintHeapAtGC) {
105 Universe::print_heap_before_gc();
106 }
107 if (_gc_heap_log != NULL) {
108 _gc_heap_log->log_heap_before();
109 }
110 }
112 void CollectedHeap::print_heap_after_gc() {
113 if (PrintHeapAtGC) {
114 Universe::print_heap_after_gc();
115 }
116 if (_gc_heap_log != NULL) {
117 _gc_heap_log->log_heap_after();
118 }
119 }
121 void CollectedHeap::register_nmethod(nmethod* nm) {
122 assert_locked_or_safepoint(CodeCache_lock);
123 }
125 void CollectedHeap::unregister_nmethod(nmethod* nm) {
126 assert_locked_or_safepoint(CodeCache_lock);
127 }
129 void CollectedHeap::trace_heap(GCWhen::Type when, GCTracer* gc_tracer) {
130 const GCHeapSummary& heap_summary = create_heap_summary();
131 const MetaspaceSummary& metaspace_summary = create_metaspace_summary();
132 gc_tracer->report_gc_heap_summary(when, heap_summary, metaspace_summary);
133 }
135 void CollectedHeap::trace_heap_before_gc(GCTracer* gc_tracer) {
136 trace_heap(GCWhen::BeforeGC, gc_tracer);
137 }
139 void CollectedHeap::trace_heap_after_gc(GCTracer* gc_tracer) {
140 trace_heap(GCWhen::AfterGC, gc_tracer);
141 }
143 // Memory state functions.
146 CollectedHeap::CollectedHeap() : _n_par_threads(0)
147 {
148 const size_t max_len = size_t(arrayOopDesc::max_array_length(T_INT));
149 const size_t elements_per_word = HeapWordSize / sizeof(jint);
150 _filler_array_max_size = align_object_size(filler_array_hdr_size() +
151 max_len / elements_per_word);
153 _barrier_set = NULL;
154 _is_gc_active = false;
155 _total_collections = _total_full_collections = 0;
156 _gc_cause = _gc_lastcause = GCCause::_no_gc;
157 NOT_PRODUCT(_promotion_failure_alot_count = 0;)
158 NOT_PRODUCT(_promotion_failure_alot_gc_number = 0;)
160 if (UsePerfData) {
161 EXCEPTION_MARK;
163 // create the gc cause jvmstat counters
164 _perf_gc_cause = PerfDataManager::create_string_variable(SUN_GC, "cause",
165 80, GCCause::to_string(_gc_cause), CHECK);
167 _perf_gc_lastcause =
168 PerfDataManager::create_string_variable(SUN_GC, "lastCause",
169 80, GCCause::to_string(_gc_lastcause), CHECK);
170 }
171 _defer_initial_card_mark = false; // strengthened by subclass in pre_initialize() below.
172 // Create the ring log
173 if (LogEvents) {
174 _gc_heap_log = new GCHeapLog();
175 } else {
176 _gc_heap_log = NULL;
177 }
178 }
180 // This interface assumes that it's being called by the
181 // vm thread. It collects the heap assuming that the
182 // heap lock is already held and that we are executing in
183 // the context of the vm thread.
184 void CollectedHeap::collect_as_vm_thread(GCCause::Cause cause) {
185 assert(Thread::current()->is_VM_thread(), "Precondition#1");
186 assert(Heap_lock->is_locked(), "Precondition#2");
187 GCCauseSetter gcs(this, cause);
188 switch (cause) {
189 case GCCause::_heap_inspection:
190 case GCCause::_heap_dump:
191 case GCCause::_metadata_GC_threshold : {
192 HandleMark hm;
193 do_full_collection(false); // don't clear all soft refs
194 break;
195 }
196 case GCCause::_last_ditch_collection: {
197 HandleMark hm;
198 do_full_collection(true); // do clear all soft refs
199 break;
200 }
201 default:
202 ShouldNotReachHere(); // Unexpected use of this function
203 }
204 }
206 void CollectedHeap::pre_initialize() {
207 // Used for ReduceInitialCardMarks (when COMPILER2 is used);
208 // otherwise remains unused.
209 #ifdef COMPILER2
210 _defer_initial_card_mark = ReduceInitialCardMarks && can_elide_tlab_store_barriers()
211 && (DeferInitialCardMark || card_mark_must_follow_store());
212 #else
213 assert(_defer_initial_card_mark == false, "Who would set it?");
214 #endif
215 }
217 #ifndef PRODUCT
218 void CollectedHeap::check_for_bad_heap_word_value(HeapWord* addr, size_t size) {
219 if (CheckMemoryInitialization && ZapUnusedHeapArea) {
220 for (size_t slot = 0; slot < size; slot += 1) {
221 assert((*(intptr_t*) (addr + slot)) != ((intptr_t) badHeapWordVal),
222 "Found badHeapWordValue in post-allocation check");
223 }
224 }
225 }
227 void CollectedHeap::check_for_non_bad_heap_word_value(HeapWord* addr, size_t size) {
228 if (CheckMemoryInitialization && ZapUnusedHeapArea) {
229 for (size_t slot = 0; slot < size; slot += 1) {
230 assert((*(intptr_t*) (addr + slot)) == ((intptr_t) badHeapWordVal),
231 "Found non badHeapWordValue in pre-allocation check");
232 }
233 }
234 }
235 #endif // PRODUCT
237 #ifdef ASSERT
238 void CollectedHeap::check_for_valid_allocation_state() {
239 Thread *thread = Thread::current();
240 // How to choose between a pending exception and a potential
241 // OutOfMemoryError? Don't allow pending exceptions.
242 // This is a VM policy failure, so how do we exhaustively test it?
243 assert(!thread->has_pending_exception(),
244 "shouldn't be allocating with pending exception");
245 if (StrictSafepointChecks) {
246 assert(thread->allow_allocation(),
247 "Allocation done by thread for which allocation is blocked "
248 "by No_Allocation_Verifier!");
249 // Allocation of an oop can always invoke a safepoint,
250 // hence, the true argument
251 thread->check_for_valid_safepoint_state(true);
252 }
253 }
254 #endif
256 HeapWord* CollectedHeap::allocate_from_tlab_slow(KlassHandle klass, Thread* thread, size_t size) {
258 // Retain tlab and allocate object in shared space if
259 // the amount free in the tlab is too large to discard.
260 if (thread->tlab().free() > thread->tlab().refill_waste_limit()) {
261 thread->tlab().record_slow_allocation(size);
262 return NULL;
263 }
265 // Discard tlab and allocate a new one.
266 // To minimize fragmentation, the last TLAB may be smaller than the rest.
267 size_t new_tlab_size = thread->tlab().compute_size(size);
269 thread->tlab().clear_before_allocation();
271 if (new_tlab_size == 0) {
272 return NULL;
273 }
275 // Allocate a new TLAB...
276 HeapWord* obj = Universe::heap()->allocate_new_tlab(new_tlab_size);
277 if (obj == NULL) {
278 return NULL;
279 }
281 AllocTracer::send_allocation_in_new_tlab_event(klass, new_tlab_size * HeapWordSize, size * HeapWordSize);
283 if (ZeroTLAB) {
284 // ..and clear it.
285 Copy::zero_to_words(obj, new_tlab_size);
286 } else {
287 // ...and zap just allocated object.
288 #ifdef ASSERT
289 // Skip mangling the space corresponding to the object header to
290 // ensure that the returned space is not considered parsable by
291 // any concurrent GC thread.
292 size_t hdr_size = oopDesc::header_size();
293 Copy::fill_to_words(obj + hdr_size, new_tlab_size - hdr_size, badHeapWordVal);
294 #endif // ASSERT
295 }
296 thread->tlab().fill(obj, obj + size, new_tlab_size);
297 return obj;
298 }
300 void CollectedHeap::flush_deferred_store_barrier(JavaThread* thread) {
301 MemRegion deferred = thread->deferred_card_mark();
302 if (!deferred.is_empty()) {
303 assert(_defer_initial_card_mark, "Otherwise should be empty");
304 {
305 // Verify that the storage points to a parsable object in heap
306 DEBUG_ONLY(oop old_obj = oop(deferred.start());)
307 assert(is_in(old_obj), "Not in allocated heap");
308 assert(!can_elide_initializing_store_barrier(old_obj),
309 "Else should have been filtered in new_store_pre_barrier()");
310 assert(old_obj->is_oop(true), "Not an oop");
311 assert(deferred.word_size() == (size_t)(old_obj->size()),
312 "Mismatch: multiple objects?");
313 }
314 BarrierSet* bs = barrier_set();
315 assert(bs->has_write_region_opt(), "No write_region() on BarrierSet");
316 bs->write_region(deferred);
317 // "Clear" the deferred_card_mark field
318 thread->set_deferred_card_mark(MemRegion());
319 }
320 assert(thread->deferred_card_mark().is_empty(), "invariant");
321 }
323 // Helper for ReduceInitialCardMarks. For performance,
324 // compiled code may elide card-marks for initializing stores
325 // to a newly allocated object along the fast-path. We
326 // compensate for such elided card-marks as follows:
327 // (a) Generational, non-concurrent collectors, such as
328 // GenCollectedHeap(ParNew,DefNew,Tenured) and
329 // ParallelScavengeHeap(ParallelGC, ParallelOldGC)
330 // need the card-mark if and only if the region is
331 // in the old gen, and do not care if the card-mark
332 // succeeds or precedes the initializing stores themselves,
333 // so long as the card-mark is completed before the next
334 // scavenge. For all these cases, we can do a card mark
335 // at the point at which we do a slow path allocation
336 // in the old gen, i.e. in this call.
337 // (b) GenCollectedHeap(ConcurrentMarkSweepGeneration) requires
338 // in addition that the card-mark for an old gen allocated
339 // object strictly follow any associated initializing stores.
340 // In these cases, the memRegion remembered below is
341 // used to card-mark the entire region either just before the next
342 // slow-path allocation by this thread or just before the next scavenge or
343 // CMS-associated safepoint, whichever of these events happens first.
344 // (The implicit assumption is that the object has been fully
345 // initialized by this point, a fact that we assert when doing the
346 // card-mark.)
347 // (c) G1CollectedHeap(G1) uses two kinds of write barriers. When a
348 // G1 concurrent marking is in progress an SATB (pre-write-)barrier is
349 // is used to remember the pre-value of any store. Initializing
350 // stores will not need this barrier, so we need not worry about
351 // compensating for the missing pre-barrier here. Turning now
352 // to the post-barrier, we note that G1 needs a RS update barrier
353 // which simply enqueues a (sequence of) dirty cards which may
354 // optionally be refined by the concurrent update threads. Note
355 // that this barrier need only be applied to a non-young write,
356 // but, like in CMS, because of the presence of concurrent refinement
357 // (much like CMS' precleaning), must strictly follow the oop-store.
358 // Thus, using the same protocol for maintaining the intended
359 // invariants turns out, serendepitously, to be the same for both
360 // G1 and CMS.
361 //
362 // For any future collector, this code should be reexamined with
363 // that specific collector in mind, and the documentation above suitably
364 // extended and updated.
365 oop CollectedHeap::new_store_pre_barrier(JavaThread* thread, oop new_obj) {
366 // If a previous card-mark was deferred, flush it now.
367 flush_deferred_store_barrier(thread);
368 if (can_elide_initializing_store_barrier(new_obj)) {
369 // The deferred_card_mark region should be empty
370 // following the flush above.
371 assert(thread->deferred_card_mark().is_empty(), "Error");
372 } else {
373 MemRegion mr((HeapWord*)new_obj, new_obj->size());
374 assert(!mr.is_empty(), "Error");
375 if (_defer_initial_card_mark) {
376 // Defer the card mark
377 thread->set_deferred_card_mark(mr);
378 } else {
379 // Do the card mark
380 BarrierSet* bs = barrier_set();
381 assert(bs->has_write_region_opt(), "No write_region() on BarrierSet");
382 bs->write_region(mr);
383 }
384 }
385 return new_obj;
386 }
388 size_t CollectedHeap::filler_array_hdr_size() {
389 return size_t(align_object_offset(arrayOopDesc::header_size(T_INT))); // align to Long
390 }
392 size_t CollectedHeap::filler_array_min_size() {
393 return align_object_size(filler_array_hdr_size()); // align to MinObjAlignment
394 }
396 #ifdef ASSERT
397 void CollectedHeap::fill_args_check(HeapWord* start, size_t words)
398 {
399 assert(words >= min_fill_size(), "too small to fill");
400 assert(words % MinObjAlignment == 0, "unaligned size");
401 assert(Universe::heap()->is_in_reserved(start), "not in heap");
402 assert(Universe::heap()->is_in_reserved(start + words - 1), "not in heap");
403 }
405 void CollectedHeap::zap_filler_array(HeapWord* start, size_t words, bool zap)
406 {
407 if (ZapFillerObjects && zap) {
408 Copy::fill_to_words(start + filler_array_hdr_size(),
409 words - filler_array_hdr_size(), 0XDEAFBABE);
410 }
411 }
412 #endif // ASSERT
414 void
415 CollectedHeap::fill_with_array(HeapWord* start, size_t words, bool zap)
416 {
417 assert(words >= filler_array_min_size(), "too small for an array");
418 assert(words <= filler_array_max_size(), "too big for a single object");
420 const size_t payload_size = words - filler_array_hdr_size();
421 const size_t len = payload_size * HeapWordSize / sizeof(jint);
422 assert((int)len >= 0, err_msg("size too large " SIZE_FORMAT " becomes %d", words, (int)len));
424 // Set the length first for concurrent GC.
425 ((arrayOop)start)->set_length((int)len);
426 post_allocation_setup_common(Universe::intArrayKlassObj(), start);
427 DEBUG_ONLY(zap_filler_array(start, words, zap);)
428 }
430 void
431 CollectedHeap::fill_with_object_impl(HeapWord* start, size_t words, bool zap)
432 {
433 assert(words <= filler_array_max_size(), "too big for a single object");
435 if (words >= filler_array_min_size()) {
436 fill_with_array(start, words, zap);
437 } else if (words > 0) {
438 assert(words == min_fill_size(), "unaligned size");
439 post_allocation_setup_common(SystemDictionary::Object_klass(), start);
440 }
441 }
443 void CollectedHeap::fill_with_object(HeapWord* start, size_t words, bool zap)
444 {
445 DEBUG_ONLY(fill_args_check(start, words);)
446 HandleMark hm; // Free handles before leaving.
447 fill_with_object_impl(start, words, zap);
448 }
450 void CollectedHeap::fill_with_objects(HeapWord* start, size_t words, bool zap)
451 {
452 DEBUG_ONLY(fill_args_check(start, words);)
453 HandleMark hm; // Free handles before leaving.
455 #ifdef _LP64
456 // A single array can fill ~8G, so multiple objects are needed only in 64-bit.
457 // First fill with arrays, ensuring that any remaining space is big enough to
458 // fill. The remainder is filled with a single object.
459 const size_t min = min_fill_size();
460 const size_t max = filler_array_max_size();
461 while (words > max) {
462 const size_t cur = words - max >= min ? max : max - min;
463 fill_with_array(start, cur, zap);
464 start += cur;
465 words -= cur;
466 }
467 #endif
469 fill_with_object_impl(start, words, zap);
470 }
472 void CollectedHeap::post_initialize() {
473 collector_policy()->post_heap_initialize();
474 }
476 HeapWord* CollectedHeap::allocate_new_tlab(size_t size) {
477 guarantee(false, "thread-local allocation buffers not supported");
478 return NULL;
479 }
481 void CollectedHeap::ensure_parsability(bool retire_tlabs) {
482 // The second disjunct in the assertion below makes a concession
483 // for the start-up verification done while the VM is being
484 // created. Callers be careful that you know that mutators
485 // aren't going to interfere -- for instance, this is permissible
486 // if we are still single-threaded and have either not yet
487 // started allocating (nothing much to verify) or we have
488 // started allocating but are now a full-fledged JavaThread
489 // (and have thus made our TLAB's) available for filling.
490 assert(SafepointSynchronize::is_at_safepoint() ||
491 !is_init_completed(),
492 "Should only be called at a safepoint or at start-up"
493 " otherwise concurrent mutator activity may make heap "
494 " unparsable again");
495 const bool use_tlab = UseTLAB;
496 const bool deferred = _defer_initial_card_mark;
497 // The main thread starts allocating via a TLAB even before it
498 // has added itself to the threads list at vm boot-up.
499 assert(!use_tlab || Threads::first() != NULL,
500 "Attempt to fill tlabs before main thread has been added"
501 " to threads list is doomed to failure!");
502 for (JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
503 if (use_tlab) thread->tlab().make_parsable(retire_tlabs);
504 #ifdef COMPILER2
505 // The deferred store barriers must all have been flushed to the
506 // card-table (or other remembered set structure) before GC starts
507 // processing the card-table (or other remembered set).
508 if (deferred) flush_deferred_store_barrier(thread);
509 #else
510 assert(!deferred, "Should be false");
511 assert(thread->deferred_card_mark().is_empty(), "Should be empty");
512 #endif
513 }
514 }
516 void CollectedHeap::accumulate_statistics_all_tlabs() {
517 if (UseTLAB) {
518 assert(SafepointSynchronize::is_at_safepoint() ||
519 !is_init_completed(),
520 "should only accumulate statistics on tlabs at safepoint");
522 ThreadLocalAllocBuffer::accumulate_statistics_before_gc();
523 }
524 }
526 void CollectedHeap::resize_all_tlabs() {
527 if (UseTLAB) {
528 assert(SafepointSynchronize::is_at_safepoint() ||
529 !is_init_completed(),
530 "should only resize tlabs at safepoint");
532 ThreadLocalAllocBuffer::resize_all_tlabs();
533 }
534 }
536 void CollectedHeap::pre_full_gc_dump(GCTimer* timer) {
537 if (HeapDumpBeforeFullGC) {
538 GCTraceTime tt("Heap Dump (before full gc): ", PrintGCDetails, false, timer);
539 // We are doing a "major" collection and a heap dump before
540 // major collection has been requested.
541 HeapDumper::dump_heap();
542 }
543 if (PrintClassHistogramBeforeFullGC) {
544 GCTraceTime tt("Class Histogram (before full gc): ", PrintGCDetails, true, timer);
545 VM_GC_HeapInspection inspector(gclog_or_tty, false /* ! full gc */);
546 inspector.doit();
547 }
548 }
550 void CollectedHeap::post_full_gc_dump(GCTimer* timer) {
551 if (HeapDumpAfterFullGC) {
552 GCTraceTime tt("Heap Dump (after full gc): ", PrintGCDetails, false, timer);
553 HeapDumper::dump_heap();
554 }
555 if (PrintClassHistogramAfterFullGC) {
556 GCTraceTime tt("Class Histogram (after full gc): ", PrintGCDetails, true, timer);
557 VM_GC_HeapInspection inspector(gclog_or_tty, false /* ! full gc */);
558 inspector.doit();
559 }
560 }
562 oop CollectedHeap::Class_obj_allocate(KlassHandle klass, int size, KlassHandle real_klass, TRAPS) {
563 debug_only(check_for_valid_allocation_state());
564 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
565 assert(size >= 0, "int won't convert to size_t");
566 HeapWord* obj;
567 assert(ScavengeRootsInCode > 0, "must be");
568 obj = common_mem_allocate_init(real_klass, size, CHECK_NULL);
569 post_allocation_setup_common(klass, obj);
570 assert(Universe::is_bootstrapping() ||
571 !((oop)obj)->is_array(), "must not be an array");
572 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
573 oop mirror = (oop)obj;
575 java_lang_Class::set_oop_size(mirror, size);
577 // Setup indirections
578 if (!real_klass.is_null()) {
579 java_lang_Class::set_klass(mirror, real_klass());
580 real_klass->set_java_mirror(mirror);
581 }
583 InstanceMirrorKlass* mk = InstanceMirrorKlass::cast(mirror->klass());
584 assert(size == mk->instance_size(real_klass), "should have been set");
586 // notify jvmti and dtrace
587 post_allocation_notify(klass, (oop)obj);
589 return mirror;
590 }
592 /////////////// Unit tests ///////////////
594 #ifndef PRODUCT
595 void CollectedHeap::test_is_in() {
596 CollectedHeap* heap = Universe::heap();
598 uintptr_t epsilon = (uintptr_t) MinObjAlignment;
599 uintptr_t heap_start = (uintptr_t) heap->_reserved.start();
600 uintptr_t heap_end = (uintptr_t) heap->_reserved.end();
602 // Test that NULL is not in the heap.
603 assert(!heap->is_in(NULL), "NULL is unexpectedly in the heap");
605 // Test that a pointer to before the heap start is reported as outside the heap.
606 assert(heap_start >= ((uintptr_t)NULL + epsilon), "sanity");
607 void* before_heap = (void*)(heap_start - epsilon);
608 assert(!heap->is_in(before_heap),
609 err_msg("before_heap: " PTR_FORMAT " is unexpectedly in the heap", before_heap));
611 // Test that a pointer to after the heap end is reported as outside the heap.
612 assert(heap_end <= ((uintptr_t)-1 - epsilon), "sanity");
613 void* after_heap = (void*)(heap_end + epsilon);
614 assert(!heap->is_in(after_heap),
615 err_msg("after_heap: " PTR_FORMAT " is unexpectedly in the heap", after_heap));
616 }
617 #endif