1 /*
2 * Copyright (c) 2001, 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 #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 "oops/oop.inline.hpp"
36 #include "oops/instanceMirrorKlass.hpp"
37 #include "runtime/init.hpp"
38 #include "services/heapDumper.hpp"
39 #ifdef TARGET_OS_FAMILY_linux
40 # include "thread_linux.inline.hpp"
41 #endif
42 #ifdef TARGET_OS_FAMILY_solaris
43 # include "thread_solaris.inline.hpp"
44 #endif
45 #ifdef TARGET_OS_FAMILY_windows
46 # include "thread_windows.inline.hpp"
47 #endif
48 #ifdef TARGET_OS_FAMILY_bsd
49 # include "thread_bsd.inline.hpp"
50 #endif
51
52
53 #ifdef ASSERT
54 int CollectedHeap::_fire_out_of_memory_count = 0;
55 #endif
56
57 size_t CollectedHeap::_filler_array_max_size = 0;
58
59 template <>
60 void EventLogBase<GCMessage>::print(outputStream* st, GCMessage& m) {
61 st->print_cr("GC heap %s", m.is_before ? "before" : "after");
62 st->print_raw(m);
63 }
64
65 void GCHeapLog::log_heap(bool before) {
66 if (!should_log()) {
67 return;
68 }
69
70 double timestamp = fetch_timestamp();
71 MutexLockerEx ml(&_mutex, Mutex::_no_safepoint_check_flag);
72 int index = compute_log_index();
73 _records[index].thread = NULL; // Its the GC thread so it's not that interesting.
74 _records[index].timestamp = timestamp;
75 _records[index].data.is_before = before;
76 stringStream st(_records[index].data.buffer(), _records[index].data.size());
77 if (before) {
78 Universe::print_heap_before_gc(&st, true);
79 } else {
80 Universe::print_heap_after_gc(&st, true);
81 }
82 }
83
84 VirtualSpaceSummary CollectedHeap::create_heap_space_summary() {
85 size_t capacity_in_words = capacity() / HeapWordSize;
86
87 return VirtualSpaceSummary(
88 reserved_region().start(), reserved_region().start() + capacity_in_words, reserved_region().end());
89 }
90
91 GCHeapSummary CollectedHeap::create_heap_summary() {
92 VirtualSpaceSummary heap_space = create_heap_space_summary();
93 return GCHeapSummary(heap_space, used());
94 }
95
96 PermGenSummary CollectedHeap::create_perm_gen_summary() {
97 VirtualSpaceSummary perm_space = create_perm_gen_space_summary();
98 SpaceSummary object_space(perm_space.start(), perm_space.committed_end(), permanent_used());
99
100 return PermGenSummary(perm_space, object_space);
101 }
102
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 }
111
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 }
120
121 void CollectedHeap::trace_heap(GCWhen::Type when, GCTracer* gc_tracer) {
122 const GCHeapSummary& heap_summary = create_heap_summary();
123 const PermGenSummary& perm_summary = create_perm_gen_summary();
124 gc_tracer->report_gc_heap_summary(when, heap_summary, perm_summary);
125 }
126
127 void CollectedHeap::trace_heap_before_gc(GCTracer* gc_tracer) {
128 trace_heap(GCWhen::BeforeGC, gc_tracer);
129 }
130
131 void CollectedHeap::trace_heap_after_gc(GCTracer* gc_tracer) {
132 trace_heap(GCWhen::AfterGC, gc_tracer);
133 }
134
135 // Memory state functions.
136
137
138 CollectedHeap::CollectedHeap() : _n_par_threads(0)
139 {
140 const size_t max_len = size_t(arrayOopDesc::max_array_length(T_INT));
141 const size_t elements_per_word = HeapWordSize / sizeof(jint);
142 _filler_array_max_size = align_object_size(filler_array_hdr_size() +
143 max_len / elements_per_word);
144
145 _barrier_set = NULL;
146 _is_gc_active = false;
147 _total_collections = _total_full_collections = 0;
148 _gc_cause = _gc_lastcause = GCCause::_no_gc;
149 NOT_PRODUCT(_promotion_failure_alot_count = 0;)
150 NOT_PRODUCT(_promotion_failure_alot_gc_number = 0;)
151
152 if (UsePerfData) {
153 EXCEPTION_MARK;
154
155 // create the gc cause jvmstat counters
156 _perf_gc_cause = PerfDataManager::create_string_variable(SUN_GC, "cause",
157 80, GCCause::to_string(_gc_cause), CHECK);
158
159 _perf_gc_lastcause =
160 PerfDataManager::create_string_variable(SUN_GC, "lastCause",
161 80, GCCause::to_string(_gc_lastcause), CHECK);
162 }
163 _defer_initial_card_mark = false; // strengthened by subclass in pre_initialize() below.
164 // Create the ring log
165 if (LogEvents) {
166 _gc_heap_log = new GCHeapLog();
167 } else {
168 _gc_heap_log = NULL;
169 }
170 }
171
172 void CollectedHeap::pre_initialize() {
173 // Used for ReduceInitialCardMarks (when COMPILER2 is used);
174 // otherwise remains unused.
175 #ifdef COMPILER2
176 _defer_initial_card_mark = ReduceInitialCardMarks && can_elide_tlab_store_barriers()
177 && (DeferInitialCardMark || card_mark_must_follow_store());
178 #else
179 assert(_defer_initial_card_mark == false, "Who would set it?");
180 #endif
181 }
182
183 #ifndef PRODUCT
184 void CollectedHeap::check_for_bad_heap_word_value(HeapWord* addr, size_t size) {
185 if (CheckMemoryInitialization && ZapUnusedHeapArea) {
186 for (size_t slot = 0; slot < size; slot += 1) {
187 assert((*(intptr_t*) (addr + slot)) != ((intptr_t) badHeapWordVal),
188 "Found badHeapWordValue in post-allocation check");
189 }
190 }
191 }
192
193 void CollectedHeap::check_for_non_bad_heap_word_value(HeapWord* addr, size_t size) {
194 if (CheckMemoryInitialization && ZapUnusedHeapArea) {
195 for (size_t slot = 0; slot < size; slot += 1) {
196 assert((*(intptr_t*) (addr + slot)) == ((intptr_t) badHeapWordVal),
197 "Found non badHeapWordValue in pre-allocation check");
198 }
199 }
200 }
201 #endif // PRODUCT
202
203 #ifdef ASSERT
204 void CollectedHeap::check_for_valid_allocation_state() {
205 Thread *thread = Thread::current();
206 // How to choose between a pending exception and a potential
207 // OutOfMemoryError? Don't allow pending exceptions.
208 // This is a VM policy failure, so how do we exhaustively test it?
209 assert(!thread->has_pending_exception(),
210 "shouldn't be allocating with pending exception");
211 if (StrictSafepointChecks) {
212 assert(thread->allow_allocation(),
213 "Allocation done by thread for which allocation is blocked "
214 "by No_Allocation_Verifier!");
215 // Allocation of an oop can always invoke a safepoint,
216 // hence, the true argument
217 thread->check_for_valid_safepoint_state(true);
218 }
219 }
220 #endif
221
222 HeapWord* CollectedHeap::allocate_from_tlab_slow(KlassHandle klass, Thread* thread, size_t size) {
223
224 // Retain tlab and allocate object in shared space if
225 // the amount free in the tlab is too large to discard.
226 if (thread->tlab().free() > thread->tlab().refill_waste_limit()) {
227 thread->tlab().record_slow_allocation(size);
228 return NULL;
229 }
230
231 // Discard tlab and allocate a new one.
232 // To minimize fragmentation, the last TLAB may be smaller than the rest.
233 size_t new_tlab_size = thread->tlab().compute_size(size);
234
235 thread->tlab().clear_before_allocation();
236
237 if (new_tlab_size == 0) {
238 return NULL;
239 }
240
241 // Allocate a new TLAB...
242 HeapWord* obj = Universe::heap()->allocate_new_tlab(new_tlab_size);
243 if (obj == NULL) {
244 return NULL;
245 }
246
247 AllocTracer::send_allocation_in_new_tlab_event(klass, new_tlab_size * HeapWordSize, size * HeapWordSize);
248
249 if (ZeroTLAB) {
250 // ..and clear it.
251 Copy::zero_to_words(obj, new_tlab_size);
252 } else {
253 // ...and zap just allocated object.
254 #ifdef ASSERT
255 // Skip mangling the space corresponding to the object header to
256 // ensure that the returned space is not considered parsable by
257 // any concurrent GC thread.
258 size_t hdr_size = oopDesc::header_size();
259 Copy::fill_to_words(obj + hdr_size, new_tlab_size - hdr_size, badHeapWordVal);
260 #endif // ASSERT
261 }
262 thread->tlab().fill(obj, obj + size, new_tlab_size);
263 return obj;
264 }
265
266 void CollectedHeap::flush_deferred_store_barrier(JavaThread* thread) {
267 MemRegion deferred = thread->deferred_card_mark();
268 if (!deferred.is_empty()) {
269 assert(_defer_initial_card_mark, "Otherwise should be empty");
270 {
271 // Verify that the storage points to a parsable object in heap
272 DEBUG_ONLY(oop old_obj = oop(deferred.start());)
273 assert(is_in(old_obj), "Not in allocated heap");
274 assert(!can_elide_initializing_store_barrier(old_obj),
275 "Else should have been filtered in new_store_pre_barrier()");
276 assert(!is_in_permanent(old_obj), "Sanity: not expected");
277 assert(old_obj->is_oop(true), "Not an oop");
278 assert(old_obj->is_parsable(), "Will not be concurrently parsable");
279 assert(deferred.word_size() == (size_t)(old_obj->size()),
280 "Mismatch: multiple objects?");
281 }
282 BarrierSet* bs = barrier_set();
283 assert(bs->has_write_region_opt(), "No write_region() on BarrierSet");
284 bs->write_region(deferred);
285 // "Clear" the deferred_card_mark field
286 thread->set_deferred_card_mark(MemRegion());
287 }
288 assert(thread->deferred_card_mark().is_empty(), "invariant");
289 }
290
291 // Helper for ReduceInitialCardMarks. For performance,
292 // compiled code may elide card-marks for initializing stores
293 // to a newly allocated object along the fast-path. We
294 // compensate for such elided card-marks as follows:
295 // (a) Generational, non-concurrent collectors, such as
296 // GenCollectedHeap(ParNew,DefNew,Tenured) and
297 // ParallelScavengeHeap(ParallelGC, ParallelOldGC)
298 // need the card-mark if and only if the region is
299 // in the old gen, and do not care if the card-mark
300 // succeeds or precedes the initializing stores themselves,
301 // so long as the card-mark is completed before the next
302 // scavenge. For all these cases, we can do a card mark
303 // at the point at which we do a slow path allocation
304 // in the old gen, i.e. in this call.
305 // (b) GenCollectedHeap(ConcurrentMarkSweepGeneration) requires
306 // in addition that the card-mark for an old gen allocated
307 // object strictly follow any associated initializing stores.
308 // In these cases, the memRegion remembered below is
309 // used to card-mark the entire region either just before the next
310 // slow-path allocation by this thread or just before the next scavenge or
311 // CMS-associated safepoint, whichever of these events happens first.
312 // (The implicit assumption is that the object has been fully
313 // initialized by this point, a fact that we assert when doing the
314 // card-mark.)
315 // (c) G1CollectedHeap(G1) uses two kinds of write barriers. When a
316 // G1 concurrent marking is in progress an SATB (pre-write-)barrier is
317 // is used to remember the pre-value of any store. Initializing
318 // stores will not need this barrier, so we need not worry about
319 // compensating for the missing pre-barrier here. Turning now
320 // to the post-barrier, we note that G1 needs a RS update barrier
321 // which simply enqueues a (sequence of) dirty cards which may
322 // optionally be refined by the concurrent update threads. Note
323 // that this barrier need only be applied to a non-young write,
324 // but, like in CMS, because of the presence of concurrent refinement
325 // (much like CMS' precleaning), must strictly follow the oop-store.
326 // Thus, using the same protocol for maintaining the intended
327 // invariants turns out, serendepitously, to be the same for both
328 // G1 and CMS.
329 //
330 // For any future collector, this code should be reexamined with
331 // that specific collector in mind, and the documentation above suitably
332 // extended and updated.
333 oop CollectedHeap::new_store_pre_barrier(JavaThread* thread, oop new_obj) {
334 // If a previous card-mark was deferred, flush it now.
335 flush_deferred_store_barrier(thread);
336 if (can_elide_initializing_store_barrier(new_obj)) {
337 // The deferred_card_mark region should be empty
338 // following the flush above.
339 assert(thread->deferred_card_mark().is_empty(), "Error");
340 } else {
341 MemRegion mr((HeapWord*)new_obj, new_obj->size());
342 assert(!mr.is_empty(), "Error");
343 if (_defer_initial_card_mark) {
344 // Defer the card mark
345 thread->set_deferred_card_mark(mr);
346 } else {
347 // Do the card mark
348 BarrierSet* bs = barrier_set();
349 assert(bs->has_write_region_opt(), "No write_region() on BarrierSet");
350 bs->write_region(mr);
351 }
352 }
353 return new_obj;
354 }
355
356 size_t CollectedHeap::filler_array_hdr_size() {
357 return size_t(align_object_offset(arrayOopDesc::header_size(T_INT))); // align to Long
358 }
359
360 size_t CollectedHeap::filler_array_min_size() {
361 return align_object_size(filler_array_hdr_size()); // align to MinObjAlignment
362 }
363
364 #ifdef ASSERT
365 void CollectedHeap::fill_args_check(HeapWord* start, size_t words)
366 {
367 assert(words >= min_fill_size(), "too small to fill");
368 assert(words % MinObjAlignment == 0, "unaligned size");
369 assert(Universe::heap()->is_in_reserved(start), "not in heap");
370 assert(Universe::heap()->is_in_reserved(start + words - 1), "not in heap");
371 }
372
373 void CollectedHeap::zap_filler_array(HeapWord* start, size_t words, bool zap)
374 {
375 if (ZapFillerObjects && zap) {
376 Copy::fill_to_words(start + filler_array_hdr_size(),
377 words - filler_array_hdr_size(), 0XDEAFBABE);
378 }
379 }
380 #endif // ASSERT
381
382 void
383 CollectedHeap::fill_with_array(HeapWord* start, size_t words, bool zap)
384 {
385 assert(words >= filler_array_min_size(), "too small for an array");
386 assert(words <= filler_array_max_size(), "too big for a single object");
387
388 const size_t payload_size = words - filler_array_hdr_size();
389 const size_t len = payload_size * HeapWordSize / sizeof(jint);
390 assert((int)len >= 0, err_msg("size too large " SIZE_FORMAT " becomes %d", words, (int)len));
391
392 // Set the length first for concurrent GC.
393 ((arrayOop)start)->set_length((int)len);
394 post_allocation_setup_common(Universe::intArrayKlassObj(), start);
395 DEBUG_ONLY(zap_filler_array(start, words, zap);)
396 }
397
398 void
399 CollectedHeap::fill_with_object_impl(HeapWord* start, size_t words, bool zap)
400 {
401 assert(words <= filler_array_max_size(), "too big for a single object");
402
403 if (words >= filler_array_min_size()) {
404 fill_with_array(start, words, zap);
405 } else if (words > 0) {
406 assert(words == min_fill_size(), "unaligned size");
407 post_allocation_setup_common(SystemDictionary::Object_klass(), start);
408 }
409 }
410
411 void CollectedHeap::fill_with_object(HeapWord* start, size_t words, bool zap)
412 {
413 DEBUG_ONLY(fill_args_check(start, words);)
414 HandleMark hm; // Free handles before leaving.
415 fill_with_object_impl(start, words, zap);
416 }
417
418 void CollectedHeap::fill_with_objects(HeapWord* start, size_t words, bool zap)
419 {
420 DEBUG_ONLY(fill_args_check(start, words);)
421 HandleMark hm; // Free handles before leaving.
422
423 #ifdef _LP64
424 // A single array can fill ~8G, so multiple objects are needed only in 64-bit.
425 // First fill with arrays, ensuring that any remaining space is big enough to
426 // fill. The remainder is filled with a single object.
427 const size_t min = min_fill_size();
428 const size_t max = filler_array_max_size();
429 while (words > max) {
430 const size_t cur = words - max >= min ? max : max - min;
431 fill_with_array(start, cur, zap);
432 start += cur;
433 words -= cur;
434 }
435 #endif
436
437 fill_with_object_impl(start, words, zap);
438 }
439
440 HeapWord* CollectedHeap::allocate_new_tlab(size_t size) {
441 guarantee(false, "thread-local allocation buffers not supported");
442 return NULL;
443 }
444
445 void CollectedHeap::ensure_parsability(bool retire_tlabs) {
446 // The second disjunct in the assertion below makes a concession
447 // for the start-up verification done while the VM is being
448 // created. Callers be careful that you know that mutators
449 // aren't going to interfere -- for instance, this is permissible
450 // if we are still single-threaded and have either not yet
451 // started allocating (nothing much to verify) or we have
452 // started allocating but are now a full-fledged JavaThread
453 // (and have thus made our TLAB's) available for filling.
454 assert(SafepointSynchronize::is_at_safepoint() ||
455 !is_init_completed(),
456 "Should only be called at a safepoint or at start-up"
457 " otherwise concurrent mutator activity may make heap "
458 " unparsable again");
459 const bool use_tlab = UseTLAB;
460 const bool deferred = _defer_initial_card_mark;
461 // The main thread starts allocating via a TLAB even before it
462 // has added itself to the threads list at vm boot-up.
463 assert(!use_tlab || Threads::first() != NULL,
464 "Attempt to fill tlabs before main thread has been added"
465 " to threads list is doomed to failure!");
466 for (JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
467 if (use_tlab) thread->tlab().make_parsable(retire_tlabs);
468 #ifdef COMPILER2
469 // The deferred store barriers must all have been flushed to the
470 // card-table (or other remembered set structure) before GC starts
471 // processing the card-table (or other remembered set).
472 if (deferred) flush_deferred_store_barrier(thread);
473 #else
474 assert(!deferred, "Should be false");
475 assert(thread->deferred_card_mark().is_empty(), "Should be empty");
476 #endif
477 }
478 }
479
480 void CollectedHeap::accumulate_statistics_all_tlabs() {
481 if (UseTLAB) {
482 assert(SafepointSynchronize::is_at_safepoint() ||
483 !is_init_completed(),
484 "should only accumulate statistics on tlabs at safepoint");
485
486 ThreadLocalAllocBuffer::accumulate_statistics_before_gc();
487 }
488 }
489
490 void CollectedHeap::resize_all_tlabs() {
491 if (UseTLAB) {
492 assert(SafepointSynchronize::is_at_safepoint() ||
493 !is_init_completed(),
494 "should only resize tlabs at safepoint");
495
496 ThreadLocalAllocBuffer::resize_all_tlabs();
497 }
498 }
499
500 void CollectedHeap::pre_full_gc_dump(GCTimer* timer) {
501 if (HeapDumpBeforeFullGC) {
502 GCTraceTime tt("Heap Dump (before full gc): ", PrintGCDetails, false, timer);
503 // We are doing a "major" collection and a heap dump before
504 // major collection has been requested.
505 HeapDumper::dump_heap();
506 }
507 if (PrintClassHistogramBeforeFullGC) {
508 GCTraceTime tt("Class Histogram (before full gc): ", PrintGCDetails, true, timer);
509 VM_GC_HeapInspection inspector(gclog_or_tty, false /* ! full gc */, false /* ! prologue */);
510 inspector.doit();
511 }
512 }
513
514 void CollectedHeap::post_full_gc_dump(GCTimer* timer) {
515 if (HeapDumpAfterFullGC) {
516 GCTraceTime tt("Heap Dump (after full gc): ", PrintGCDetails, false, timer);
517 HeapDumper::dump_heap();
518 }
519 if (PrintClassHistogramAfterFullGC) {
520 GCTraceTime tt("Class Histogram (after full gc): ", PrintGCDetails, true, timer);
521 VM_GC_HeapInspection inspector(gclog_or_tty, false /* ! full gc */, false /* ! prologue */);
522 inspector.doit();
523 }
524 }
525
526 oop CollectedHeap::Class_obj_allocate(KlassHandle klass, int size, KlassHandle real_klass, TRAPS) {
527 debug_only(check_for_valid_allocation_state());
528 assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
529 assert(size >= 0, "int won't convert to size_t");
530 HeapWord* obj;
531 if (JavaObjectsInPerm) {
532 obj = common_permanent_mem_allocate_init(size, CHECK_NULL);
533 } else {
534 assert(ScavengeRootsInCode > 0, "must be");
535 obj = common_mem_allocate_init(real_klass, size, CHECK_NULL);
536 }
537 post_allocation_setup_common(klass, obj);
538 assert(Universe::is_bootstrapping() ||
539 !((oop)obj)->blueprint()->oop_is_array(), "must not be an array");
540 NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
541 oop mirror = (oop)obj;
542
543 java_lang_Class::set_oop_size(mirror, size);
544
545 // Setup indirections
546 if (!real_klass.is_null()) {
547 java_lang_Class::set_klass(mirror, real_klass());
548 real_klass->set_java_mirror(mirror);
549 }
550
551 instanceMirrorKlass* mk = instanceMirrorKlass::cast(mirror->klass());
552 assert(size == mk->instance_size(real_klass), "should have been set");
553
554 // notify jvmti and dtrace
555 post_allocation_notify(klass, (oop)obj);
556
557 return mirror;
558 }
559
560 /////////////// Unit tests ///////////////
561
562 #ifndef PRODUCT
563 void CollectedHeap::test_is_in() {
564 CollectedHeap* heap = Universe::heap();
565
566 uintptr_t epsilon = (uintptr_t) MinObjAlignment;
567 uintptr_t heap_start = (uintptr_t) heap->_reserved.start();
568 uintptr_t heap_end = (uintptr_t) heap->_reserved.end();
569
570 // Test that NULL is not in the heap.
571 assert(!heap->is_in(NULL), "NULL is unexpectedly in the heap");
572
573 // Test that a pointer to before the heap start is reported as outside the heap.
574 assert(heap_start >= ((uintptr_t)NULL + epsilon), "sanity");
575 void* before_heap = (void*)(heap_start - epsilon);
576 assert(!heap->is_in(before_heap),
577 err_msg("before_heap: " PTR_FORMAT " is unexpectedly in the heap", before_heap));
578
579 // Test that a pointer to after the heap end is reported as outside the heap.
580 assert(heap_end <= ((uintptr_t)-1 - epsilon), "sanity");
581 void* after_heap = (void*)(heap_end + epsilon);
582 assert(!heap->is_in(after_heap),
583 err_msg("after_heap: " PTR_FORMAT " is unexpectedly in the heap", after_heap));
584 }
585 #endif