1 /*
2 * Copyright (c) 2015, 2016, 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 "code/compiledIC.hpp"
27 #include "code/compiledMethod.inline.hpp"
28 #include "code/scopeDesc.hpp"
29 #include "code/codeCache.hpp"
30 #include "prims/methodHandles.hpp"
31 #include "interpreter/bytecode.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "runtime/mutexLocker.hpp"
34
35 CompiledMethod::CompiledMethod(Method* method, const char* name, CompilerType type, const CodeBlobLayout& layout, int frame_complete_offset, int frame_size, ImmutableOopMapSet* oop_maps, bool caller_must_gc_arguments)
36 : CodeBlob(name, type, layout, frame_complete_offset, frame_size, oop_maps, caller_must_gc_arguments),
37 _method(method), _mark_for_deoptimization_status(not_marked) {
38 init_defaults();
39 }
40
41 CompiledMethod::CompiledMethod(Method* method, const char* name, CompilerType type, int size, int header_size, CodeBuffer* cb, int frame_complete_offset, int frame_size, OopMapSet* oop_maps, bool caller_must_gc_arguments)
42 : CodeBlob(name, type, CodeBlobLayout((address) this, size, header_size, cb), cb, frame_complete_offset, frame_size, oop_maps, caller_must_gc_arguments),
43 _method(method), _mark_for_deoptimization_status(not_marked) {
44 init_defaults();
45 }
46
47 void CompiledMethod::init_defaults() {
48 _has_unsafe_access = 0;
49 _has_method_handle_invokes = 0;
50 _lazy_critical_native = 0;
51 _has_wide_vectors = 0;
52 _unloading_clock = 0;
53 }
54
55 bool CompiledMethod::is_method_handle_return(address return_pc) {
56 if (!has_method_handle_invokes()) return false;
57 PcDesc* pd = pc_desc_at(return_pc);
58 if (pd == NULL)
59 return false;
60 return pd->is_method_handle_invoke();
61 }
62
63 // Returns a string version of the method state.
64 const char* CompiledMethod::state() const {
65 int state = get_state();
66 switch (state) {
67 case in_use:
68 return "in use";
69 case not_used:
70 return "not_used";
71 case not_entrant:
72 return "not_entrant";
73 case zombie:
74 return "zombie";
75 case unloaded:
76 return "unloaded";
77 default:
78 fatal("unexpected method state: %d", state);
79 return NULL;
80 }
81 }
82
83 //-----------------------------------------------------------------------------
84
85 void CompiledMethod::add_exception_cache_entry(ExceptionCache* new_entry) {
86 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
87 assert(new_entry != NULL,"Must be non null");
88 assert(new_entry->next() == NULL, "Must be null");
89
90 ExceptionCache *ec = exception_cache();
91 if (ec != NULL) {
92 new_entry->set_next(ec);
93 }
94 release_set_exception_cache(new_entry);
95 }
96
97 void CompiledMethod::clean_exception_cache(BoolObjectClosure* is_alive) {
98 ExceptionCache* prev = NULL;
99 ExceptionCache* curr = exception_cache();
100
101 while (curr != NULL) {
102 ExceptionCache* next = curr->next();
103
104 Klass* ex_klass = curr->exception_type();
105 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
106 if (prev == NULL) {
107 set_exception_cache(next);
108 } else {
109 prev->set_next(next);
110 }
111 delete curr;
112 // prev stays the same.
113 } else {
114 prev = curr;
115 }
116
117 curr = next;
118 }
119 }
120
121 // public method for accessing the exception cache
122 // These are the public access methods.
123 address CompiledMethod::handler_for_exception_and_pc(Handle exception, address pc) {
124 // We never grab a lock to read the exception cache, so we may
125 // have false negatives. This is okay, as it can only happen during
126 // the first few exception lookups for a given nmethod.
127 ExceptionCache* ec = exception_cache();
128 while (ec != NULL) {
129 address ret_val;
130 if ((ret_val = ec->match(exception,pc)) != NULL) {
131 return ret_val;
132 }
133 ec = ec->next();
134 }
135 return NULL;
136 }
137
138 void CompiledMethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
139 // There are potential race conditions during exception cache updates, so we
140 // must own the ExceptionCache_lock before doing ANY modifications. Because
141 // we don't lock during reads, it is possible to have several threads attempt
142 // to update the cache with the same data. We need to check for already inserted
143 // copies of the current data before adding it.
144
145 MutexLocker ml(ExceptionCache_lock);
146 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
147
148 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
149 target_entry = new ExceptionCache(exception,pc,handler);
150 add_exception_cache_entry(target_entry);
151 }
152 }
153
154 //-------------end of code for ExceptionCache--------------
155
156 // private method for handling exception cache
157 // These methods are private, and used to manipulate the exception cache
158 // directly.
159 ExceptionCache* CompiledMethod::exception_cache_entry_for_exception(Handle exception) {
160 ExceptionCache* ec = exception_cache();
161 while (ec != NULL) {
162 if (ec->match_exception_with_space(exception)) {
163 return ec;
164 }
165 ec = ec->next();
166 }
167 return NULL;
168 }
169
170 bool CompiledMethod::is_at_poll_return(address pc) {
171 RelocIterator iter(this, pc, pc+1);
172 while (iter.next()) {
173 if (iter.type() == relocInfo::poll_return_type)
174 return true;
175 }
176 return false;
177 }
178
179
180 bool CompiledMethod::is_at_poll_or_poll_return(address pc) {
181 RelocIterator iter(this, pc, pc+1);
182 while (iter.next()) {
183 relocInfo::relocType t = iter.type();
184 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
185 return true;
186 }
187 return false;
188 }
189
190 void CompiledMethod::verify_oop_relocations() {
191 // Ensure sure that the code matches the current oop values
192 RelocIterator iter(this, NULL, NULL);
193 while (iter.next()) {
194 if (iter.type() == relocInfo::oop_type) {
195 oop_Relocation* reloc = iter.oop_reloc();
196 if (!reloc->oop_is_immediate()) {
197 reloc->verify_oop_relocation();
198 }
199 }
200 }
201 }
202
203
204 ScopeDesc* CompiledMethod::scope_desc_at(address pc) {
205 PcDesc* pd = pc_desc_at(pc);
206 guarantee(pd != NULL, "scope must be present");
207 return new ScopeDesc(this, pd->scope_decode_offset(),
208 pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(),
209 pd->return_oop());
210 }
211
212 void CompiledMethod::cleanup_inline_caches(bool clean_all/*=false*/) {
213 assert_locked_or_safepoint(CompiledIC_lock);
214
215 // If the method is not entrant or zombie then a JMP is plastered over the
216 // first few bytes. If an oop in the old code was there, that oop
217 // should not get GC'd. Skip the first few bytes of oops on
218 // not-entrant methods.
219 address low_boundary = verified_entry_point();
220 if (!is_in_use() && is_nmethod()) {
221 low_boundary += NativeJump::instruction_size;
222 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
223 // This means that the low_boundary is going to be a little too high.
224 // This shouldn't matter, since oops of non-entrant methods are never used.
225 // In fact, why are we bothering to look at oops in a non-entrant method??
226 }
227
228 // Find all calls in an nmethod and clear the ones that point to non-entrant,
229 // zombie and unloaded nmethods.
230 ResourceMark rm;
231 RelocIterator iter(this, low_boundary);
232 while(iter.next()) {
233 switch(iter.type()) {
234 case relocInfo::virtual_call_type:
235 case relocInfo::opt_virtual_call_type: {
236 CompiledIC *ic = CompiledIC_at(&iter);
237 // Ok, to lookup references to zombies here
238 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
239 if( cb != NULL && cb->is_compiled() ) {
240 CompiledMethod* nm = cb->as_compiled_method();
241 // Clean inline caches pointing to zombie, non-entrant and unloaded methods
242 if (clean_all || !nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean(is_alive());
243 }
244 break;
245 }
246 case relocInfo::static_call_type: {
247 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
248 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
249 if( cb != NULL && cb->is_compiled() ) {
250 CompiledMethod* cm = cb->as_compiled_method();
251 // Clean inline caches pointing to zombie, non-entrant and unloaded methods
252 if (clean_all || !cm->is_in_use() || (cm->method()->code() != cm)) {
253 csc->set_to_clean();
254 }
255 }
256 break;
257 }
258 }
259 }
260 }
261
262 int CompiledMethod::verify_icholder_relocations() {
263 ResourceMark rm;
264 int count = 0;
265
266 RelocIterator iter(this);
267 while(iter.next()) {
268 if (iter.type() == relocInfo::virtual_call_type) {
269 if (CompiledIC::is_icholder_call_site(iter.virtual_call_reloc(), this)) {
270 CompiledIC *ic = CompiledIC_at(&iter);
271 if (TraceCompiledIC) {
272 tty->print("noticed icholder " INTPTR_FORMAT " ", p2i(ic->cached_icholder()));
273 ic->print();
274 }
275 assert(ic->cached_icholder() != NULL, "must be non-NULL");
276 count++;
277 }
278 }
279 }
280
281 return count;
282 }
283
284 // Method that knows how to preserve outgoing arguments at call. This method must be
285 // called with a frame corresponding to a Java invoke
286 void CompiledMethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
287 #ifndef SHARK
288 if (method() != NULL && !method()->is_native()) {
289 address pc = fr.pc();
290 SimpleScopeDesc ssd(this, pc);
291 Bytecode_invoke call(ssd.method(), ssd.bci());
292 bool has_receiver = call.has_receiver();
293 bool has_appendix = call.has_appendix();
294 Symbol* signature = call.signature();
295
296 // The method attached by JIT-compilers should be used, if present.
297 // Bytecode can be inaccurate in such case.
298 Method* callee = attached_method_before_pc(pc);
299 if (callee != NULL) {
300 has_receiver = !(callee->access_flags().is_static());
301 has_appendix = false;
302 signature = callee->signature();
303 }
304
305 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
306 }
307 #endif // !SHARK
308 }
309
310 // -----------------------------------------------------------------------------
311 // CompiledMethod::get_deopt_original_pc
312 //
313 // Return the original PC for the given PC if:
314 // (a) the given PC belongs to a nmethod and
315 // (b) it is a deopt PC
316
317
318 Method* CompiledMethod::attached_method(address call_instr) {
319 assert(code_contains(call_instr), "not part of the nmethod");
320 RelocIterator iter(this, call_instr, call_instr + 1);
321 while (iter.next()) {
322 if (iter.addr() == call_instr) {
323 switch(iter.type()) {
324 case relocInfo::static_call_type: return iter.static_call_reloc()->method_value();
325 case relocInfo::opt_virtual_call_type: return iter.opt_virtual_call_reloc()->method_value();
326 case relocInfo::virtual_call_type: return iter.virtual_call_reloc()->method_value();
327 }
328 }
329 }
330 return NULL; // not found
331 }
332
333 Method* CompiledMethod::attached_method_before_pc(address pc) {
334 if (NativeCall::is_call_before(pc)) {
335 NativeCall* ncall = nativeCall_before(pc);
336 return attached_method(ncall->instruction_address());
337 }
338 return NULL; // not a call
339 }
340
341 void CompiledMethod::clear_inline_caches() {
342 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
343 if (is_zombie()) {
344 return;
345 }
346
347 RelocIterator iter(this);
348 while (iter.next()) {
349 iter.reloc()->clear_inline_cache();
350 }
351 }
352
353 // Clear ICStubs of all compiled ICs
354 void CompiledMethod::clear_ic_stubs() {
355 assert_locked_or_safepoint(CompiledIC_lock);
356 RelocIterator iter(this);
357 while(iter.next()) {
358 if (iter.type() == relocInfo::virtual_call_type) {
359 CompiledIC* ic = CompiledIC_at(&iter);
360 ic->clear_ic_stub();
361 }
362 }
363 }
364
365 #ifdef ASSERT
366
367 class CheckClass : AllStatic {
368 static BoolObjectClosure* _is_alive;
369
370 // Check class_loader is alive for this bit of metadata.
371 static void check_class(Metadata* md) {
372 Klass* klass = NULL;
373 if (md->is_klass()) {
374 klass = ((Klass*)md);
375 } else if (md->is_method()) {
376 klass = ((Method*)md)->method_holder();
377 } else if (md->is_methodData()) {
378 klass = ((MethodData*)md)->method()->method_holder();
379 } else {
380 md->print();
381 ShouldNotReachHere();
382 }
383 assert(klass->is_loader_alive(_is_alive), "must be alive");
384 }
385 public:
386 static void do_check_class(BoolObjectClosure* is_alive, CompiledMethod* nm) {
387 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
388 _is_alive = is_alive;
389 nm->metadata_do(check_class);
390 }
391 };
392
393 // This is called during a safepoint so can use static data
394 BoolObjectClosure* CheckClass::_is_alive = NULL;
395 #endif // ASSERT
396
397
398 void CompiledMethod::clean_ic_if_metadata_is_dead(CompiledIC *ic, BoolObjectClosure *is_alive) {
399 if (ic->is_icholder_call()) {
400 // The only exception is compiledICHolder oops which may
401 // yet be marked below. (We check this further below).
402 CompiledICHolder* cichk_oop = ic->cached_icholder();
403
404 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
405 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
406 return;
407 }
408 } else {
409 Metadata* ic_oop = ic->cached_metadata();
410 if (ic_oop != NULL) {
411 if (ic_oop->is_klass()) {
412 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
413 return;
414 }
415 } else if (ic_oop->is_method()) {
416 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
417 return;
418 }
419 } else {
420 ShouldNotReachHere();
421 }
422 }
423 }
424
425 ic->set_to_clean();
426 }
427
428 unsigned char CompiledMethod::_global_unloading_clock = 0;
429
430 void CompiledMethod::increase_unloading_clock() {
431 _global_unloading_clock++;
432 if (_global_unloading_clock == 0) {
433 // _nmethods are allocated with _unloading_clock == 0,
434 // so 0 is never used as a clock value.
435 _global_unloading_clock = 1;
436 }
437 }
438
439 void CompiledMethod::set_unloading_clock(unsigned char unloading_clock) {
440 OrderAccess::release_store((volatile jubyte*)&_unloading_clock, unloading_clock);
441 }
442
443 unsigned char CompiledMethod::unloading_clock() {
444 return (unsigned char)OrderAccess::load_acquire((volatile jubyte*)&_unloading_clock);
445 }
446
447 // Processing of oop references should have been sufficient to keep
448 // all strong references alive. Any weak references should have been
449 // cleared as well. Visit all the metadata and ensure that it's
450 // really alive.
451 void CompiledMethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
452 #ifdef ASSERT
453 RelocIterator iter(this, low_boundary);
454 while (iter.next()) {
455 // static_stub_Relocations may have dangling references to
456 // Method*s so trim them out here. Otherwise it looks like
457 // compiled code is maintaining a link to dead metadata.
458 address static_call_addr = NULL;
459 if (iter.type() == relocInfo::opt_virtual_call_type) {
460 CompiledIC* cic = CompiledIC_at(&iter);
461 if (!cic->is_call_to_interpreted()) {
462 static_call_addr = iter.addr();
463 }
464 } else if (iter.type() == relocInfo::static_call_type) {
465 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
466 if (!csc->is_call_to_interpreted()) {
467 static_call_addr = iter.addr();
468 }
469 }
470 if (static_call_addr != NULL) {
471 RelocIterator sciter(this, low_boundary);
472 while (sciter.next()) {
473 if (sciter.type() == relocInfo::static_stub_type &&
474 sciter.static_stub_reloc()->static_call() == static_call_addr) {
475 sciter.static_stub_reloc()->clear_inline_cache();
476 }
477 }
478 }
479 }
480 // Check that the metadata embedded in the nmethod is alive
481 CheckClass::do_check_class(is_alive, this);
482 #endif
483 }
484
485 // This is called at the end of the strong tracing/marking phase of a
486 // GC to unload an nmethod if it contains otherwise unreachable
487 // oops.
488
489 void CompiledMethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
490 // Make sure the oop's ready to receive visitors
491 assert(!is_zombie() && !is_unloaded(),
492 "should not call follow on zombie or unloaded nmethod");
493
494 // If the method is not entrant then a JMP is plastered over the
495 // first few bytes. If an oop in the old code was there, that oop
496 // should not get GC'd. Skip the first few bytes of oops on
497 // not-entrant methods.
498 address low_boundary = verified_entry_point();
499 if (is_not_entrant()) {
500 low_boundary += NativeJump::instruction_size;
501 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
502 // (See comment above.)
503 }
504
505 // The RedefineClasses() API can cause the class unloading invariant
506 // to no longer be true. See jvmtiExport.hpp for details.
507 // Also, leave a debugging breadcrumb in local flag.
508 if (JvmtiExport::has_redefined_a_class()) {
509 // This set of the unloading_occurred flag is done before the
510 // call to post_compiled_method_unload() so that the unloading
511 // of this nmethod is reported.
512 unloading_occurred = true;
513 }
514
515 // Exception cache
516 clean_exception_cache(is_alive);
517
518 // If class unloading occurred we first iterate over all inline caches and
519 // clear ICs where the cached oop is referring to an unloaded klass or method.
520 // The remaining live cached oops will be traversed in the relocInfo::oop_type
521 // iteration below.
522 if (unloading_occurred) {
523 RelocIterator iter(this, low_boundary);
524 while(iter.next()) {
525 if (iter.type() == relocInfo::virtual_call_type) {
526 CompiledIC *ic = CompiledIC_at(&iter);
527 clean_ic_if_metadata_is_dead(ic, is_alive);
528 }
529 }
530 }
531
532 if (do_unloading_oops(low_boundary, is_alive, unloading_occurred)) {
533 return;
534 }
535
536 #if INCLUDE_JVMCI
537 if (do_unloading_jvmci(is_alive, unloading_occurred)) {
538 return;
539 }
540 #endif
541
542 // Ensure that all metadata is still alive
543 verify_metadata_loaders(low_boundary, is_alive);
544 }
545
546 template <class CompiledICorStaticCall>
547 static bool clean_if_nmethod_is_unloaded(CompiledICorStaticCall *ic, address addr, BoolObjectClosure *is_alive, CompiledMethod* from) {
548 // Ok, to lookup references to zombies here
549 CodeBlob *cb = CodeCache::find_blob_unsafe(addr);
550 CompiledMethod* nm = (cb != NULL) ? cb->as_compiled_method_or_null() : NULL;
551 if (nm != NULL) {
552 if (nm->unloading_clock() != CompiledMethod::global_unloading_clock()) {
553 // The nmethod has not been processed yet.
554 return true;
555 }
556
557 // Clean inline caches pointing to both zombie and not_entrant methods
558 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
559 ic->set_to_clean();
560 assert(ic->is_clean(), "nmethod " PTR_FORMAT "not clean %s", p2i(from), from->method()->name_and_sig_as_C_string());
561 }
562 }
563
564 return false;
565 }
566
567 static bool clean_if_nmethod_is_unloaded(CompiledIC *ic, BoolObjectClosure *is_alive, CompiledMethod* from) {
568 return clean_if_nmethod_is_unloaded(ic, ic->ic_destination(), is_alive, from);
569 }
570
571 static bool clean_if_nmethod_is_unloaded(CompiledStaticCall *csc, BoolObjectClosure *is_alive, CompiledMethod* from) {
572 return clean_if_nmethod_is_unloaded(csc, csc->destination(), is_alive, from);
573 }
574
575 bool CompiledMethod::do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred) {
576 ResourceMark rm;
577
578 // Make sure the oop's ready to receive visitors
579 assert(!is_zombie() && !is_unloaded(),
580 "should not call follow on zombie or unloaded nmethod");
581
582 // If the method is not entrant then a JMP is plastered over the
583 // first few bytes. If an oop in the old code was there, that oop
584 // should not get GC'd. Skip the first few bytes of oops on
585 // not-entrant methods.
586 address low_boundary = verified_entry_point();
587 if (is_not_entrant()) {
588 low_boundary += NativeJump::instruction_size;
589 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
590 // (See comment above.)
591 }
592
593 // The RedefineClasses() API can cause the class unloading invariant
594 // to no longer be true. See jvmtiExport.hpp for details.
595 // Also, leave a debugging breadcrumb in local flag.
596 if (JvmtiExport::has_redefined_a_class()) {
597 // This set of the unloading_occurred flag is done before the
598 // call to post_compiled_method_unload() so that the unloading
599 // of this nmethod is reported.
600 unloading_occurred = true;
601 }
602
603 // Exception cache
604 clean_exception_cache(is_alive);
605
606 bool postponed = false;
607
608 RelocIterator iter(this, low_boundary);
609 while(iter.next()) {
610
611 switch (iter.type()) {
612
613 case relocInfo::virtual_call_type:
614 if (unloading_occurred) {
615 // If class unloading occurred we first iterate over all inline caches and
616 // clear ICs where the cached oop is referring to an unloaded klass or method.
617 clean_ic_if_metadata_is_dead(CompiledIC_at(&iter), is_alive);
618 }
619
620 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
621 break;
622
623 case relocInfo::opt_virtual_call_type:
624 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
625 break;
626
627 case relocInfo::static_call_type:
628 postponed |= clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
629 break;
630
631 case relocInfo::oop_type:
632 // handled by do_unloading_oops below
633 break;
634
635 case relocInfo::metadata_type:
636 break; // nothing to do.
637 }
638 }
639
640 if (do_unloading_oops(low_boundary, is_alive, unloading_occurred)) {
641 return postponed;
642 }
643
644 #if INCLUDE_JVMCI
645 if (do_unloading_jvmci(is_alive, unloading_occurred)) {
646 return postponed;
647 }
648 #endif
649
650 // Ensure that all metadata is still alive
651 verify_metadata_loaders(low_boundary, is_alive);
652
653 return postponed;
654 }
655
656 void CompiledMethod::do_unloading_parallel_postponed(BoolObjectClosure* is_alive, bool unloading_occurred) {
657 ResourceMark rm;
658
659 // Make sure the oop's ready to receive visitors
660 assert(!is_zombie(),
661 "should not call follow on zombie nmethod");
662
663 // If the method is not entrant then a JMP is plastered over the
664 // first few bytes. If an oop in the old code was there, that oop
665 // should not get GC'd. Skip the first few bytes of oops on
666 // not-entrant methods.
667 address low_boundary = verified_entry_point();
668 if (is_not_entrant()) {
669 low_boundary += NativeJump::instruction_size;
670 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
671 // (See comment above.)
672 }
673
674 RelocIterator iter(this, low_boundary);
675 while(iter.next()) {
676
677 switch (iter.type()) {
678
679 case relocInfo::virtual_call_type:
680 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
681 break;
682
683 case relocInfo::opt_virtual_call_type:
684 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
685 break;
686
687 case relocInfo::static_call_type:
688 clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
689 break;
690 }
691 }
692 }