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comparison src/share/vm/compiler/oopMap.cpp @ 0:a61af66fc99e jdk7-b24

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author duke
date Sat, 01 Dec 2007 00:00:00 +0000
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1 /*
2 * Copyright 1998-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 # include "incls/_precompiled.incl"
26 # include "incls/_oopMap.cpp.incl"
27
28 // OopMapStream
29
30 OopMapStream::OopMapStream(OopMap* oop_map) {
31 if(oop_map->omv_data() == NULL) {
32 _stream = new CompressedReadStream(oop_map->write_stream()->buffer());
33 } else {
34 _stream = new CompressedReadStream(oop_map->omv_data());
35 }
36 _mask = OopMapValue::type_mask_in_place;
37 _size = oop_map->omv_count();
38 _position = 0;
39 _valid_omv = false;
40 }
41
42
43 OopMapStream::OopMapStream(OopMap* oop_map, int oop_types_mask) {
44 if(oop_map->omv_data() == NULL) {
45 _stream = new CompressedReadStream(oop_map->write_stream()->buffer());
46 } else {
47 _stream = new CompressedReadStream(oop_map->omv_data());
48 }
49 _mask = oop_types_mask;
50 _size = oop_map->omv_count();
51 _position = 0;
52 _valid_omv = false;
53 }
54
55
56 void OopMapStream::find_next() {
57 while(_position++ < _size) {
58 _omv.read_from(_stream);
59 if(((int)_omv.type() & _mask) > 0) {
60 _valid_omv = true;
61 return;
62 }
63 }
64 _valid_omv = false;
65 }
66
67
68 // OopMap
69
70 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
71 // slots to hold 4-byte values like ints and floats in the LP64 build.
72 OopMap::OopMap(int frame_size, int arg_count) {
73 // OopMaps are usually quite so small, so pick a small initial size
74 set_write_stream(new CompressedWriteStream(32));
75 set_omv_data(NULL);
76 set_omv_count(0);
77
78 #ifdef ASSERT
79 _locs_length = VMRegImpl::stack2reg(0)->value() + frame_size + arg_count;
80 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
81 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
82 #endif
83 }
84
85
86 OopMap::OopMap(OopMap::DeepCopyToken, OopMap* source) {
87 // This constructor does a deep copy
88 // of the source OopMap.
89 set_write_stream(new CompressedWriteStream(source->omv_count() * 2));
90 set_omv_data(NULL);
91 set_omv_count(0);
92 set_offset(source->offset());
93
94 #ifdef ASSERT
95 _locs_length = source->_locs_length;
96 _locs_used = NEW_RESOURCE_ARRAY(OopMapValue::oop_types, _locs_length);
97 for(int i = 0; i < _locs_length; i++) _locs_used[i] = OopMapValue::unused_value;
98 #endif
99
100 // We need to copy the entries too.
101 for (OopMapStream oms(source); !oms.is_done(); oms.next()) {
102 OopMapValue omv = oms.current();
103 omv.write_on(write_stream());
104 increment_count();
105 }
106 }
107
108
109 OopMap* OopMap::deep_copy() {
110 return new OopMap(_deep_copy_token, this);
111 }
112
113
114 void OopMap::copy_to(address addr) {
115 memcpy(addr,this,sizeof(OopMap));
116 memcpy(addr + sizeof(OopMap),write_stream()->buffer(),write_stream()->position());
117 OopMap* new_oop = (OopMap*)addr;
118 new_oop->set_omv_data_size(write_stream()->position());
119 new_oop->set_omv_data((unsigned char *)(addr + sizeof(OopMap)));
120 new_oop->set_write_stream(NULL);
121 }
122
123
124 int OopMap::heap_size() const {
125 int size = sizeof(OopMap);
126 int align = sizeof(void *) - 1;
127 if(write_stream() != NULL) {
128 size += write_stream()->position();
129 } else {
130 size += omv_data_size();
131 }
132 // Align to a reasonable ending point
133 size = ((size+align) & ~align);
134 return size;
135 }
136
137 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd
138 // slots to hold 4-byte values like ints and floats in the LP64 build.
139 void OopMap::set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional) {
140
141 assert(reg->value() < _locs_length, "too big reg value for stack size");
142 assert( _locs_used[reg->value()] == OopMapValue::unused_value, "cannot insert twice" );
143 debug_only( _locs_used[reg->value()] = x; )
144
145 OopMapValue o(reg, x);
146
147 if(x == OopMapValue::callee_saved_value) {
148 // This can never be a stack location, so we don't need to transform it.
149 assert(optional->is_reg(), "Trying to callee save a stack location");
150 o.set_content_reg(optional);
151 } else if(x == OopMapValue::derived_oop_value) {
152 o.set_content_reg(optional);
153 }
154
155 o.write_on(write_stream());
156 increment_count();
157 }
158
159
160 void OopMap::set_oop(VMReg reg) {
161 set_xxx(reg, OopMapValue::oop_value, VMRegImpl::Bad());
162 }
163
164
165 void OopMap::set_value(VMReg reg) {
166 // At this time, we only need value entries in our OopMap when ZapDeadCompiledLocals is active.
167 if (ZapDeadCompiledLocals)
168 set_xxx(reg, OopMapValue::value_value, VMRegImpl::Bad());
169 }
170
171
172 void OopMap::set_dead(VMReg reg) {
173 // At this time, we only need dead entries in our OopMap when ZapDeadCompiledLocals is active.
174 if (ZapDeadCompiledLocals) {
175 set_xxx(reg, OopMapValue::dead_value, VMRegImpl::Bad());
176 }
177 }
178
179
180 void OopMap::set_callee_saved(VMReg reg, VMReg caller_machine_register ) {
181 set_xxx(reg, OopMapValue::callee_saved_value, caller_machine_register);
182 }
183
184
185 void OopMap::set_derived_oop(VMReg reg, VMReg derived_from_local_register ) {
186 if( reg == derived_from_local_register ) {
187 // Actually an oop, derived shares storage with base,
188 set_oop(reg);
189 } else {
190 set_xxx(reg, OopMapValue::derived_oop_value, derived_from_local_register);
191 }
192 }
193
194 void OopMap::set_stack_obj(VMReg reg) {
195 set_xxx(reg, OopMapValue::stack_obj, VMRegImpl::Bad());
196 }
197
198 // OopMapSet
199
200 OopMapSet::OopMapSet() {
201 set_om_size(MinOopMapAllocation);
202 set_om_count(0);
203 OopMap** temp = NEW_RESOURCE_ARRAY(OopMap*, om_size());
204 set_om_data(temp);
205 }
206
207
208 void OopMapSet::grow_om_data() {
209 int new_size = om_size() * 2;
210 OopMap** new_data = NEW_RESOURCE_ARRAY(OopMap*, new_size);
211 memcpy(new_data,om_data(),om_size() * sizeof(OopMap*));
212 set_om_size(new_size);
213 set_om_data(new_data);
214 }
215
216
217 void OopMapSet::copy_to(address addr) {
218 address temp = addr;
219 int align = sizeof(void *) - 1;
220 // Copy this
221 memcpy(addr,this,sizeof(OopMapSet));
222 temp += sizeof(OopMapSet);
223 temp = (address)((intptr_t)(temp + align) & ~align);
224 // Do the needed fixups to the new OopMapSet
225 OopMapSet* new_set = (OopMapSet*)addr;
226 new_set->set_om_data((OopMap**)temp);
227 // Allow enough space for the OopMap pointers
228 temp += (om_count() * sizeof(OopMap*));
229
230 for(int i=0; i < om_count(); i++) {
231 OopMap* map = at(i);
232 map->copy_to((address)temp);
233 new_set->set(i,(OopMap*)temp);
234 temp += map->heap_size();
235 }
236 // This "locks" the OopMapSet
237 new_set->set_om_size(-1);
238 }
239
240
241 void OopMapSet::add_gc_map(int pc_offset, OopMap *map ) {
242 assert(om_size() != -1,"Cannot grow a fixed OopMapSet");
243
244 if(om_count() >= om_size()) {
245 grow_om_data();
246 }
247 map->set_offset(pc_offset);
248
249 #ifdef ASSERT
250 if(om_count() > 0) {
251 OopMap* last = at(om_count()-1);
252 if (last->offset() == map->offset() ) {
253 fatal("OopMap inserted twice");
254 }
255 if(last->offset() > map->offset()) {
256 tty->print_cr( "WARNING, maps not sorted: pc[%d]=%d, pc[%d]=%d",
257 om_count(),last->offset(),om_count()+1,map->offset());
258 }
259 }
260 #endif // ASSERT
261
262 set(om_count(),map);
263 increment_count();
264 }
265
266
267 int OopMapSet::heap_size() const {
268 // The space we use
269 int size = sizeof(OopMap);
270 int align = sizeof(void *) - 1;
271 size = ((size+align) & ~align);
272 size += om_count() * sizeof(OopMap*);
273
274 // Now add in the space needed for the indivdiual OopMaps
275 for(int i=0; i < om_count(); i++) {
276 size += at(i)->heap_size();
277 }
278 // We don't need to align this, it will be naturally pointer aligned
279 return size;
280 }
281
282
283 OopMap* OopMapSet::singular_oop_map() {
284 guarantee(om_count() == 1, "Make sure we only have a single gc point");
285 return at(0);
286 }
287
288
289 OopMap* OopMapSet::find_map_at_offset(int pc_offset) const {
290 int i, len = om_count();
291 assert( len > 0, "must have pointer maps" );
292
293 // Scan through oopmaps. Stop when current offset is either equal or greater
294 // than the one we are looking for.
295 for( i = 0; i < len; i++) {
296 if( at(i)->offset() >= pc_offset )
297 break;
298 }
299
300 assert( i < len, "oopmap not found" );
301
302 OopMap* m = at(i);
303 assert( m->offset() == pc_offset, "oopmap not found" );
304 return m;
305 }
306
307 class DoNothingClosure: public OopClosure {
308 public: void do_oop(oop* p) {}
309 };
310 static DoNothingClosure do_nothing;
311
312 static void add_derived_oop(oop* base, oop* derived) {
313 #ifndef TIERED
314 COMPILER1_PRESENT(ShouldNotReachHere();)
315 #endif // TIERED
316 #ifdef COMPILER2
317 DerivedPointerTable::add(derived, base);
318 #endif // COMPILER2
319 }
320
321
322 #ifndef PRODUCT
323 static void trace_codeblob_maps(const frame *fr, const RegisterMap *reg_map) {
324 // Print oopmap and regmap
325 tty->print_cr("------ ");
326 CodeBlob* cb = fr->cb();
327 OopMapSet* maps = cb->oop_maps();
328 OopMap* map = cb->oop_map_for_return_address(fr->pc());
329 map->print();
330 if( cb->is_nmethod() ) {
331 nmethod* nm = (nmethod*)cb;
332 // native wrappers have no scope data, it is implied
333 if (nm->is_native_method()) {
334 tty->print("bci: 0 (native)");
335 } else {
336 ScopeDesc* scope = nm->scope_desc_at(fr->pc());
337 tty->print("bci: %d ",scope->bci());
338 }
339 }
340 tty->cr();
341 fr->print_on(tty);
342 tty->print(" ");
343 cb->print_value_on(tty); tty->cr();
344 reg_map->print();
345 tty->print_cr("------ ");
346
347 }
348 #endif // PRODUCT
349
350 void OopMapSet::oops_do(const frame *fr, const RegisterMap* reg_map, OopClosure* f) {
351 // add derived oops to a table
352 all_do(fr, reg_map, f, add_derived_oop, &do_nothing, &do_nothing);
353 }
354
355
356 void OopMapSet::all_do(const frame *fr, const RegisterMap *reg_map,
357 OopClosure* oop_fn, void derived_oop_fn(oop*, oop*),
358 OopClosure* value_fn, OopClosure* dead_fn) {
359 CodeBlob* cb = fr->cb();
360 {
361 assert(cb != NULL, "no codeblob");
362 }
363
364 NOT_PRODUCT(if (TraceCodeBlobStacks) trace_codeblob_maps(fr, reg_map);)
365
366 OopMapSet* maps = cb->oop_maps();
367 OopMap* map = cb->oop_map_for_return_address(fr->pc());
368 assert(map != NULL, " no ptr map found");
369
370 // handle derived pointers first (otherwise base pointer may be
371 // changed before derived pointer offset has been collected)
372 OopMapValue omv;
373 {
374 OopMapStream oms(map,OopMapValue::derived_oop_value);
375 if (!oms.is_done()) {
376 #ifndef TIERED
377 COMPILER1_PRESENT(ShouldNotReachHere();)
378 #endif // !TIERED
379 // Protect the operation on the derived pointers. This
380 // protects the addition of derived pointers to the shared
381 // derived pointer table in DerivedPointerTable::add().
382 MutexLockerEx x(DerivedPointerTableGC_lock, Mutex::_no_safepoint_check_flag);
383 do {
384 omv = oms.current();
385 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
386 if ( loc != NULL ) {
387 oop *base_loc = fr->oopmapreg_to_location(omv.content_reg(), reg_map);
388 oop *derived_loc = loc;
389 derived_oop_fn(base_loc, derived_loc);
390 }
391 oms.next();
392 } while (!oms.is_done());
393 }
394 }
395
396 // We want dead, value and oop oop_types
397 int mask = OopMapValue::oop_value | OopMapValue::value_value | OopMapValue::dead_value;
398 {
399 for (OopMapStream oms(map,mask); !oms.is_done(); oms.next()) {
400 omv = oms.current();
401 oop* loc = fr->oopmapreg_to_location(omv.reg(),reg_map);
402 if ( loc != NULL ) {
403 if ( omv.type() == OopMapValue::oop_value ) {
404 #ifdef ASSERT
405 if (COMPILER2_PRESENT(!DoEscapeAnalysis &&) !Universe::heap()->is_in_or_null(*loc)) {
406 tty->print_cr("# Found non oop pointer. Dumping state at failure");
407 // try to dump out some helpful debugging information
408 trace_codeblob_maps(fr, reg_map);
409 omv.print();
410 tty->print_cr("loc = %p *loc = %p\n", loc, (address)*loc);
411 // do the real assert.
412 assert(Universe::heap()->is_in_or_null(*loc), "found non oop pointer");
413 }
414 #endif // ASSERT
415 oop_fn->do_oop(loc);
416 } else if ( omv.type() == OopMapValue::value_value ) {
417 value_fn->do_oop(loc);
418 } else if ( omv.type() == OopMapValue::dead_value ) {
419 dead_fn->do_oop(loc);
420 }
421 }
422 }
423 }
424
425 #ifdef COMPILER2
426 if (DoEscapeAnalysis) {
427 for (OopMapStream oms(map, OopMapValue::stack_obj); !oms.is_done(); oms.next()) {
428 omv = oms.current();
429 assert(omv.is_stack_loc(), "should refer to stack location");
430 oop loc = (oop) fr->oopmapreg_to_location(omv.reg(),reg_map);
431 oop_fn->do_oop(&loc);
432 }
433 }
434 #endif // COMPILER2
435 }
436
437
438 // Update callee-saved register info for the following frame
439 void OopMapSet::update_register_map(const frame *fr, RegisterMap *reg_map) {
440 ResourceMark rm;
441 CodeBlob* cb = fr->cb();
442 assert(cb != NULL, "no codeblob");
443
444 // Any reg might be saved by a safepoint handler (see generate_handler_blob).
445 const int max_saved_on_entry_reg_count = ConcreteRegisterImpl::number_of_registers;
446 assert( reg_map->_update_for_id == NULL || fr->is_older(reg_map->_update_for_id),
447 "already updated this map; do not 'update' it twice!" );
448 debug_only(reg_map->_update_for_id = fr->id());
449
450 // Check if caller must update oop argument
451 assert((reg_map->include_argument_oops() ||
452 !cb->caller_must_gc_arguments(reg_map->thread())),
453 "include_argument_oops should already be set");
454
455 int nof_callee = 0;
456 oop* locs[2*max_saved_on_entry_reg_count+1];
457 VMReg regs[2*max_saved_on_entry_reg_count+1];
458 // ("+1" because max_saved_on_entry_reg_count might be zero)
459
460 // Scan through oopmap and find location of all callee-saved registers
461 // (we do not do update in place, since info could be overwritten)
462
463 address pc = fr->pc();
464
465 OopMap* map = cb->oop_map_for_return_address(pc);
466
467 assert(map != NULL, " no ptr map found");
468
469 OopMapValue omv;
470 for(OopMapStream oms(map,OopMapValue::callee_saved_value); !oms.is_done(); oms.next()) {
471 omv = oms.current();
472 assert(nof_callee < 2*max_saved_on_entry_reg_count, "overflow");
473 regs[nof_callee] = omv.content_reg();
474 locs[nof_callee] = fr->oopmapreg_to_location(omv.reg(),reg_map);
475 nof_callee++;
476 }
477
478 // Check that runtime stubs save all callee-saved registers
479 #ifdef COMPILER2
480 assert(cb->is_compiled_by_c1() || !cb->is_runtime_stub() ||
481 (nof_callee >= SAVED_ON_ENTRY_REG_COUNT || nof_callee >= C_SAVED_ON_ENTRY_REG_COUNT),
482 "must save all");
483 #endif // COMPILER2
484
485 // Copy found callee-saved register to reg_map
486 for(int i = 0; i < nof_callee; i++) {
487 reg_map->set_location(regs[i], (address)locs[i]);
488 }
489 }
490
491 //=============================================================================
492 // Non-Product code
493
494 #ifndef PRODUCT
495
496 bool OopMap::has_derived_pointer() const {
497 #ifndef TIERED
498 COMPILER1_PRESENT(return false);
499 #endif // !TIERED
500 #ifdef COMPILER2
501 OopMapStream oms((OopMap*)this,OopMapValue::derived_oop_value);
502 return oms.is_done();
503 #else
504 return false;
505 #endif // COMPILER2
506 }
507
508
509 void print_register_type(OopMapValue::oop_types x, VMReg optional) {
510 switch( x ) {
511 case OopMapValue::oop_value:
512 tty->print("Oop");
513 break;
514 case OopMapValue::value_value:
515 tty->print("Value" );
516 break;
517 case OopMapValue::dead_value:
518 tty->print("Dead" );
519 break;
520 case OopMapValue::callee_saved_value:
521 tty->print("Callers_" );
522 optional->print();
523 break;
524 case OopMapValue::derived_oop_value:
525 tty->print("Derived_oop_" );
526 optional->print();
527 break;
528 case OopMapValue::stack_obj:
529 tty->print("Stack");
530 break;
531 default:
532 ShouldNotReachHere();
533 }
534 }
535
536
537 void OopMapValue::print() const {
538 reg()->print();
539 tty->print("=");
540 print_register_type(type(),content_reg());
541 tty->print(" ");
542 }
543
544
545 void OopMap::print_on(outputStream* st) const {
546 OopMapValue omv;
547 for(OopMapStream oms((OopMap*)this); !oms.is_done(); oms.next()) {
548 omv = oms.current();
549 omv.print_on(st);
550 }
551 }
552
553
554 void OopMapSet::print_on(outputStream* st) const {
555 int i, len = om_count();
556
557 st->print_cr("OopMapSet contains %d OopMaps\n",len);
558
559 for( i = 0; i < len; i++) {
560 OopMap* m = at(i);
561 st->print_cr("OopMap #%d offset:%p",i,m->offset());
562 m->print_on(st);
563 st->print_cr("\n");
564 }
565 }
566 #endif // !PRODUCT
567
568
569 //------------------------------DerivedPointerTable---------------------------
570
571 #ifdef COMPILER2
572
573 class DerivedPointerEntry : public CHeapObj {
574 private:
575 oop* _location; // Location of derived pointer (also pointing to the base)
576 intptr_t _offset; // Offset from base pointer
577 public:
578 DerivedPointerEntry(oop* location, intptr_t offset) { _location = location; _offset = offset; }
579 oop* location() { return _location; }
580 intptr_t offset() { return _offset; }
581 };
582
583
584 GrowableArray<DerivedPointerEntry*>* DerivedPointerTable::_list = NULL;
585 bool DerivedPointerTable::_active = false;
586
587
588 void DerivedPointerTable::clear() {
589 // The first time, we create the list. Otherwise it should be
590 // empty. If not, then we have probably forgotton to call
591 // update_pointers after last GC/Scavenge.
592 assert (!_active, "should not be active");
593 assert(_list == NULL || _list->length() == 0, "table not empty");
594 if (_list == NULL) {
595 _list = new (ResourceObj::C_HEAP) GrowableArray<DerivedPointerEntry*>(10, true); // Allocated on C heap
596 }
597 _active = true;
598 }
599
600
601 // Returns value of location as an int
602 intptr_t value_of_loc(oop *pointer) { return (intptr_t)(*pointer); }
603
604
605 void DerivedPointerTable::add(oop *derived_loc, oop *base_loc) {
606 assert(Universe::heap()->is_in_or_null(*base_loc), "not an oop");
607 assert(derived_loc != base_loc, "Base and derived in same location");
608 if (_active) {
609 assert(*derived_loc != (oop)base_loc, "location already added");
610 assert(_list != NULL, "list must exist");
611 intptr_t offset = value_of_loc(derived_loc) - value_of_loc(base_loc);
612 assert(offset >= -1000000, "wrong derived pointer info");
613
614 if (TraceDerivedPointers) {
615 tty->print_cr(
616 "Add derived pointer@" INTPTR_FORMAT
617 " - Derived: " INTPTR_FORMAT
618 " Base: " INTPTR_FORMAT " (@" INTPTR_FORMAT ") (Offset: %d)",
619 derived_loc, (address)*derived_loc, (address)*base_loc, base_loc, offset
620 );
621 }
622 // Set derived oop location to point to base.
623 *derived_loc = (oop)base_loc;
624 assert_lock_strong(DerivedPointerTableGC_lock);
625 DerivedPointerEntry *entry = new DerivedPointerEntry(derived_loc, offset);
626 _list->append(entry);
627 }
628 }
629
630
631 void DerivedPointerTable::update_pointers() {
632 assert(_list != NULL, "list must exist");
633 for(int i = 0; i < _list->length(); i++) {
634 DerivedPointerEntry* entry = _list->at(i);
635 oop* derived_loc = entry->location();
636 intptr_t offset = entry->offset();
637 // The derived oop was setup to point to location of base
638 oop base = **(oop**)derived_loc;
639 assert(Universe::heap()->is_in_or_null(base), "must be an oop");
640
641 *derived_loc = (oop)(((address)base) + offset);
642 assert(value_of_loc(derived_loc) - value_of_loc(&base) == offset, "sanity check");
643
644 if (TraceDerivedPointers) {
645 tty->print_cr("Updating derived pointer@" INTPTR_FORMAT
646 " - Derived: " INTPTR_FORMAT " Base: " INTPTR_FORMAT " (Offset: %d)",
647 derived_loc, (address)*derived_loc, (address)base, offset);
648 }
649
650 // Delete entry
651 delete entry;
652 _list->at_put(i, NULL);
653 }
654 // Clear list, so it is ready for next traversal (this is an invariant)
655 if (TraceDerivedPointers && !_list->is_empty()) {
656 tty->print_cr("--------------------------");
657 }
658 _list->clear();
659 _active = false;
660 }
661
662 #endif // COMPILER2