1 /*
2 * Copyright (c) 2015, 2018, 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.inline.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "oops/method.inline.hpp"
34 #include "runtime/mutexLocker.hpp"
35
36 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)
37 : CodeBlob(name, type, layout, frame_complete_offset, frame_size, oop_maps, caller_must_gc_arguments),
38 _method(method), _mark_for_deoptimization_status(not_marked) {
39 init_defaults();
40 }
41
42 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)
43 : CodeBlob(name, type, CodeBlobLayout((address) this, size, header_size, cb), cb, frame_complete_offset, frame_size, oop_maps, caller_must_gc_arguments),
44 _method(method), _mark_for_deoptimization_status(not_marked) {
45 init_defaults();
46 }
47
48 void CompiledMethod::init_defaults() {
49 _has_unsafe_access = 0;
50 _has_method_handle_invokes = 0;
51 _lazy_critical_native = 0;
52 _has_wide_vectors = 0;
53 _unloading_clock = 0;
54 }
55
56 bool CompiledMethod::is_method_handle_return(address return_pc) {
57 if (!has_method_handle_invokes()) return false;
58 PcDesc* pd = pc_desc_at(return_pc);
59 if (pd == NULL)
60 return false;
61 return pd->is_method_handle_invoke();
62 }
63
64 // Returns a string version of the method state.
65 const char* CompiledMethod::state() const {
66 int state = get_state();
67 switch (state) {
68 case not_installed:
69 return "not installed";
70 case in_use:
71 return "in use";
72 case not_used:
73 return "not_used";
74 case not_entrant:
75 return "not_entrant";
76 case zombie:
77 return "zombie";
78 case unloaded:
79 return "unloaded";
80 default:
81 fatal("unexpected method state: %d", state);
82 return NULL;
83 }
84 }
85
86 //-----------------------------------------------------------------------------
87
88 void CompiledMethod::add_exception_cache_entry(ExceptionCache* new_entry) {
89 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
90 assert(new_entry != NULL,"Must be non null");
91 assert(new_entry->next() == NULL, "Must be null");
92
93 ExceptionCache *ec = exception_cache();
94 if (ec != NULL) {
95 new_entry->set_next(ec);
96 }
97 release_set_exception_cache(new_entry);
98 }
99
100 void CompiledMethod::clean_exception_cache(BoolObjectClosure* is_alive) {
101 ExceptionCache* prev = NULL;
102 ExceptionCache* curr = exception_cache();
103
104 while (curr != NULL) {
105 ExceptionCache* next = curr->next();
106
107 Klass* ex_klass = curr->exception_type();
108 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
109 if (prev == NULL) {
110 set_exception_cache(next);
111 } else {
112 prev->set_next(next);
113 }
114 delete curr;
115 // prev stays the same.
116 } else {
117 prev = curr;
118 }
119
120 curr = next;
121 }
122 }
123
124 // public method for accessing the exception cache
125 // These are the public access methods.
126 address CompiledMethod::handler_for_exception_and_pc(Handle exception, address pc) {
127 // We never grab a lock to read the exception cache, so we may
128 // have false negatives. This is okay, as it can only happen during
129 // the first few exception lookups for a given nmethod.
130 ExceptionCache* ec = exception_cache();
131 while (ec != NULL) {
132 address ret_val;
133 if ((ret_val = ec->match(exception,pc)) != NULL) {
134 return ret_val;
135 }
136 ec = ec->next();
137 }
138 return NULL;
139 }
140
141 void CompiledMethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
142 // There are potential race conditions during exception cache updates, so we
143 // must own the ExceptionCache_lock before doing ANY modifications. Because
144 // we don't lock during reads, it is possible to have several threads attempt
145 // to update the cache with the same data. We need to check for already inserted
146 // copies of the current data before adding it.
147
148 MutexLocker ml(ExceptionCache_lock);
149 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
150
151 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
152 target_entry = new ExceptionCache(exception,pc,handler);
153 add_exception_cache_entry(target_entry);
154 }
155 }
156
157 //-------------end of code for ExceptionCache--------------
158
159 // private method for handling exception cache
160 // These methods are private, and used to manipulate the exception cache
161 // directly.
162 ExceptionCache* CompiledMethod::exception_cache_entry_for_exception(Handle exception) {
163 ExceptionCache* ec = exception_cache();
164 while (ec != NULL) {
165 if (ec->match_exception_with_space(exception)) {
166 return ec;
167 }
168 ec = ec->next();
169 }
170 return NULL;
171 }
172
173 bool CompiledMethod::is_at_poll_return(address pc) {
174 RelocIterator iter(this, pc, pc+1);
175 while (iter.next()) {
176 if (iter.type() == relocInfo::poll_return_type)
177 return true;
178 }
179 return false;
180 }
181
182
183 bool CompiledMethod::is_at_poll_or_poll_return(address pc) {
184 RelocIterator iter(this, pc, pc+1);
185 while (iter.next()) {
186 relocInfo::relocType t = iter.type();
187 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
188 return true;
189 }
190 return false;
191 }
192
193 void CompiledMethod::verify_oop_relocations() {
194 // Ensure sure that the code matches the current oop values
195 RelocIterator iter(this, NULL, NULL);
196 while (iter.next()) {
197 if (iter.type() == relocInfo::oop_type) {
198 oop_Relocation* reloc = iter.oop_reloc();
199 if (!reloc->oop_is_immediate()) {
200 reloc->verify_oop_relocation();
201 }
202 }
203 }
204 }
205
206
207 ScopeDesc* CompiledMethod::scope_desc_at(address pc) {
208 PcDesc* pd = pc_desc_at(pc);
209 guarantee(pd != NULL, "scope must be present");
210 return new ScopeDesc(this, pd->scope_decode_offset(),
211 pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(),
212 pd->return_oop());
213 }
214
215 ScopeDesc* CompiledMethod::scope_desc_near(address pc) {
216 PcDesc* pd = pc_desc_near(pc);
217 guarantee(pd != NULL, "scope must be present");
218 return new ScopeDesc(this, pd->scope_decode_offset(),
219 pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(),
220 pd->return_oop());
221 }
222
223 void CompiledMethod::cleanup_inline_caches(bool clean_all/*=false*/) {
224 assert_locked_or_safepoint(CompiledIC_lock);
225
226 // If the method is not entrant or zombie then a JMP is plastered over the
227 // first few bytes. If an oop in the old code was there, that oop
228 // should not get GC'd. Skip the first few bytes of oops on
229 // not-entrant methods.
230 address low_boundary = verified_entry_point();
231 if (!is_in_use() && is_nmethod()) {
232 low_boundary += NativeJump::instruction_size;
233 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
234 // This means that the low_boundary is going to be a little too high.
235 // This shouldn't matter, since oops of non-entrant methods are never used.
236 // In fact, why are we bothering to look at oops in a non-entrant method??
237 }
238
239 // Find all calls in an nmethod and clear the ones that point to non-entrant,
240 // zombie and unloaded nmethods.
241 ResourceMark rm;
242 RelocIterator iter(this, low_boundary);
243 while(iter.next()) {
244 switch(iter.type()) {
245 case relocInfo::virtual_call_type:
246 case relocInfo::opt_virtual_call_type: {
247 CompiledIC *ic = CompiledIC_at(&iter);
248 // Ok, to lookup references to zombies here
249 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
250 if( cb != NULL && cb->is_compiled() ) {
251 CompiledMethod* nm = cb->as_compiled_method();
252 // Clean inline caches pointing to zombie, non-entrant and unloaded methods
253 if (clean_all || !nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean(is_alive());
254 }
255 break;
256 }
257 case relocInfo::static_call_type: {
258 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
259 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
260 if( cb != NULL && cb->is_compiled() ) {
261 CompiledMethod* cm = cb->as_compiled_method();
262 // Clean inline caches pointing to zombie, non-entrant and unloaded methods
263 if (clean_all || !cm->is_in_use() || (cm->method()->code() != cm)) {
264 csc->set_to_clean();
265 }
266 }
267 break;
268 }
269 default:
270 break;
271 }
272 }
273 }
274
275 int CompiledMethod::verify_icholder_relocations() {
276 ResourceMark rm;
277 int count = 0;
278
279 RelocIterator iter(this);
280 while(iter.next()) {
281 if (iter.type() == relocInfo::virtual_call_type) {
282 if (CompiledIC::is_icholder_call_site(iter.virtual_call_reloc(), this)) {
283 CompiledIC *ic = CompiledIC_at(&iter);
284 if (TraceCompiledIC) {
285 tty->print("noticed icholder " INTPTR_FORMAT " ", p2i(ic->cached_icholder()));
286 ic->print();
287 }
288 assert(ic->cached_icholder() != NULL, "must be non-NULL");
289 count++;
290 }
291 }
292 }
293
294 return count;
295 }
296
297 // Method that knows how to preserve outgoing arguments at call. This method must be
298 // called with a frame corresponding to a Java invoke
299 void CompiledMethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
300 if (method() != NULL && !method()->is_native()) {
301 address pc = fr.pc();
302 SimpleScopeDesc ssd(this, pc);
303 Bytecode_invoke call(ssd.method(), ssd.bci());
304 bool has_receiver = call.has_receiver();
305 bool has_appendix = call.has_appendix();
306 Symbol* signature = call.signature();
307
308 // The method attached by JIT-compilers should be used, if present.
309 // Bytecode can be inaccurate in such case.
310 Method* callee = attached_method_before_pc(pc);
311 if (callee != NULL) {
312 has_receiver = !(callee->access_flags().is_static());
313 has_appendix = false;
314 signature = callee->signature();
315 }
316
317 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
318 }
319 }
320
321 Method* CompiledMethod::attached_method(address call_instr) {
322 assert(code_contains(call_instr), "not part of the nmethod");
323 RelocIterator iter(this, call_instr, call_instr + 1);
324 while (iter.next()) {
325 if (iter.addr() == call_instr) {
326 switch(iter.type()) {
327 case relocInfo::static_call_type: return iter.static_call_reloc()->method_value();
328 case relocInfo::opt_virtual_call_type: return iter.opt_virtual_call_reloc()->method_value();
329 case relocInfo::virtual_call_type: return iter.virtual_call_reloc()->method_value();
330 default: break;
331 }
332 }
333 }
334 return NULL; // not found
335 }
336
337 Method* CompiledMethod::attached_method_before_pc(address pc) {
338 if (NativeCall::is_call_before(pc)) {
339 NativeCall* ncall = nativeCall_before(pc);
340 return attached_method(ncall->instruction_address());
341 }
342 return NULL; // not a call
343 }
344
345 void CompiledMethod::clear_inline_caches() {
346 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
347 if (is_zombie()) {
348 return;
349 }
350
351 RelocIterator iter(this);
352 while (iter.next()) {
353 iter.reloc()->clear_inline_cache();
354 }
355 }
356
357 // Clear ICStubs of all compiled ICs
358 void CompiledMethod::clear_ic_stubs() {
359 assert_locked_or_safepoint(CompiledIC_lock);
360 RelocIterator iter(this);
361 while(iter.next()) {
362 if (iter.type() == relocInfo::virtual_call_type) {
363 CompiledIC* ic = CompiledIC_at(&iter);
364 ic->clear_ic_stub();
365 }
366 }
367 }
368
369 #ifdef ASSERT
370
371 class CheckClass : AllStatic {
372 static BoolObjectClosure* _is_alive;
373
374 // Check class_loader is alive for this bit of metadata.
375 static void check_class(Metadata* md) {
376 Klass* klass = NULL;
377 if (md->is_klass()) {
378 klass = ((Klass*)md);
379 } else if (md->is_method()) {
380 klass = ((Method*)md)->method_holder();
381 } else if (md->is_methodData()) {
382 klass = ((MethodData*)md)->method()->method_holder();
383 } else {
384 md->print();
385 ShouldNotReachHere();
386 }
387 assert(klass->is_loader_alive(_is_alive), "must be alive");
388 }
389 public:
390 static void do_check_class(BoolObjectClosure* is_alive, CompiledMethod* nm) {
391 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
392 _is_alive = is_alive;
393 nm->metadata_do(check_class);
394 }
395 };
396
397 // This is called during a safepoint so can use static data
398 BoolObjectClosure* CheckClass::_is_alive = NULL;
399 #endif // ASSERT
400
401
402 void CompiledMethod::clean_ic_if_metadata_is_dead(CompiledIC *ic, BoolObjectClosure *is_alive) {
403 if (ic->is_icholder_call()) {
404 // The only exception is compiledICHolder oops which may
405 // yet be marked below. (We check this further below).
406 CompiledICHolder* cichk_oop = ic->cached_icholder();
407
408 if (cichk_oop->is_loader_alive(is_alive)) {
409 return;
410 }
411 } else {
412 Metadata* ic_oop = ic->cached_metadata();
413 if (ic_oop != NULL) {
414 if (ic_oop->is_klass()) {
415 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
416 return;
417 }
418 } else if (ic_oop->is_method()) {
419 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
420 return;
421 }
422 } else {
423 ShouldNotReachHere();
424 }
425 }
426 }
427
428 ic->set_to_clean();
429 }
430
431 unsigned char CompiledMethod::_global_unloading_clock = 0;
432
433 void CompiledMethod::increase_unloading_clock() {
434 _global_unloading_clock++;
435 if (_global_unloading_clock == 0) {
436 // _nmethods are allocated with _unloading_clock == 0,
437 // so 0 is never used as a clock value.
438 _global_unloading_clock = 1;
439 }
440 }
441
442 void CompiledMethod::set_unloading_clock(unsigned char unloading_clock) {
443 OrderAccess::release_store(&_unloading_clock, unloading_clock);
444 }
445
446 unsigned char CompiledMethod::unloading_clock() {
447 return OrderAccess::load_acquire(&_unloading_clock);
448 }
449
450 // Processing of oop references should have been sufficient to keep
451 // all strong references alive. Any weak references should have been
452 // cleared as well. Visit all the metadata and ensure that it's
453 // really alive.
454 void CompiledMethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
455 #ifdef ASSERT
456 RelocIterator iter(this, low_boundary);
457 while (iter.next()) {
458 // static_stub_Relocations may have dangling references to
459 // Method*s so trim them out here. Otherwise it looks like
460 // compiled code is maintaining a link to dead metadata.
461 address static_call_addr = NULL;
462 if (iter.type() == relocInfo::opt_virtual_call_type) {
463 CompiledIC* cic = CompiledIC_at(&iter);
464 if (!cic->is_call_to_interpreted()) {
465 static_call_addr = iter.addr();
466 }
467 } else if (iter.type() == relocInfo::static_call_type) {
468 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
469 if (!csc->is_call_to_interpreted()) {
470 static_call_addr = iter.addr();
471 }
472 }
473 if (static_call_addr != NULL) {
474 RelocIterator sciter(this, low_boundary);
475 while (sciter.next()) {
476 if (sciter.type() == relocInfo::static_stub_type &&
477 sciter.static_stub_reloc()->static_call() == static_call_addr) {
478 sciter.static_stub_reloc()->clear_inline_cache();
479 }
480 }
481 }
482 }
483 // Check that the metadata embedded in the nmethod is alive
484 CheckClass::do_check_class(is_alive, this);
485 #endif
486 }
487
488 // This is called at the end of the strong tracing/marking phase of a
489 // GC to unload an nmethod if it contains otherwise unreachable
490 // oops.
491
492 void CompiledMethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
493 // Make sure the oop's ready to receive visitors
494 assert(!is_zombie() && !is_unloaded(),
495 "should not call follow on zombie or unloaded nmethod");
496
497 // If the method is not entrant then a JMP is plastered over the
498 // first few bytes. If an oop in the old code was there, that oop
499 // should not get GC'd. Skip the first few bytes of oops on
500 // not-entrant methods.
501 address low_boundary = verified_entry_point();
502 if (is_not_entrant()) {
503 low_boundary += NativeJump::instruction_size;
504 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
505 // (See comment above.)
506 }
507
508 // The RedefineClasses() API can cause the class unloading invariant
509 // to no longer be true. See jvmtiExport.hpp for details.
510 // Also, leave a debugging breadcrumb in local flag.
511 if (JvmtiExport::has_redefined_a_class()) {
512 // This set of the unloading_occurred flag is done before the
513 // call to post_compiled_method_unload() so that the unloading
514 // of this nmethod is reported.
515 unloading_occurred = true;
516 }
517
518 // Exception cache
519 clean_exception_cache(is_alive);
520
521 // If class unloading occurred we first iterate over all inline caches and
522 // clear ICs where the cached oop is referring to an unloaded klass or method.
523 // The remaining live cached oops will be traversed in the relocInfo::oop_type
524 // iteration below.
525 if (unloading_occurred) {
526 RelocIterator iter(this, low_boundary);
527 while(iter.next()) {
528 if (iter.type() == relocInfo::virtual_call_type) {
529 CompiledIC *ic = CompiledIC_at(&iter);
530 clean_ic_if_metadata_is_dead(ic, is_alive);
531 }
532 }
533 }
534
535 if (do_unloading_oops(low_boundary, is_alive, unloading_occurred)) {
536 return;
537 }
538
539 #if INCLUDE_JVMCI
540 if (do_unloading_jvmci(is_alive, unloading_occurred)) {
541 return;
542 }
543 #endif
544
545 // Ensure that all metadata is still alive
546 verify_metadata_loaders(low_boundary, is_alive);
547 }
548
549 template <class CompiledICorStaticCall>
550 static bool clean_if_nmethod_is_unloaded(CompiledICorStaticCall *ic, address addr, BoolObjectClosure *is_alive, CompiledMethod* from) {
551 // Ok, to lookup references to zombies here
552 CodeBlob *cb = CodeCache::find_blob_unsafe(addr);
553 CompiledMethod* nm = (cb != NULL) ? cb->as_compiled_method_or_null() : NULL;
554 if (nm != NULL) {
555 if (nm->unloading_clock() != CompiledMethod::global_unloading_clock()) {
556 // The nmethod has not been processed yet.
557 return true;
558 }
559
560 // Clean inline caches pointing to both zombie and not_entrant methods
561 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
562 ic->set_to_clean();
563 assert(ic->is_clean(), "nmethod " PTR_FORMAT "not clean %s", p2i(from), from->method()->name_and_sig_as_C_string());
564 }
565 }
566
567 return false;
568 }
569
570 static bool clean_if_nmethod_is_unloaded(CompiledIC *ic, BoolObjectClosure *is_alive, CompiledMethod* from) {
571 return clean_if_nmethod_is_unloaded(ic, ic->ic_destination(), is_alive, from);
572 }
573
574 static bool clean_if_nmethod_is_unloaded(CompiledStaticCall *csc, BoolObjectClosure *is_alive, CompiledMethod* from) {
575 return clean_if_nmethod_is_unloaded(csc, csc->destination(), is_alive, from);
576 }
577
578 bool CompiledMethod::do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred) {
579 ResourceMark rm;
580
581 // Make sure the oop's ready to receive visitors
582 assert(!is_zombie() && !is_unloaded(),
583 "should not call follow on zombie or unloaded nmethod");
584
585 // If the method is not entrant then a JMP is plastered over the
586 // first few bytes. If an oop in the old code was there, that oop
587 // should not get GC'd. Skip the first few bytes of oops on
588 // not-entrant methods.
589 address low_boundary = verified_entry_point();
590 if (is_not_entrant()) {
591 low_boundary += NativeJump::instruction_size;
592 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
593 // (See comment above.)
594 }
595
596 // The RedefineClasses() API can cause the class unloading invariant
597 // to no longer be true. See jvmtiExport.hpp for details.
598 // Also, leave a debugging breadcrumb in local flag.
599 if (JvmtiExport::has_redefined_a_class()) {
600 // This set of the unloading_occurred flag is done before the
601 // call to post_compiled_method_unload() so that the unloading
602 // of this nmethod is reported.
603 unloading_occurred = true;
604 }
605
606 // Exception cache
607 clean_exception_cache(is_alive);
608
609 bool postponed = false;
610
611 RelocIterator iter(this, low_boundary);
612 while(iter.next()) {
613
614 switch (iter.type()) {
615
616 case relocInfo::virtual_call_type:
617 if (unloading_occurred) {
618 // If class unloading occurred we first iterate over all inline caches and
619 // clear ICs where the cached oop is referring to an unloaded klass or method.
620 clean_ic_if_metadata_is_dead(CompiledIC_at(&iter), is_alive);
621 }
622
623 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
624 break;
625
626 case relocInfo::opt_virtual_call_type:
627 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
628 break;
629
630 case relocInfo::static_call_type:
631 postponed |= clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
632 break;
633
634 case relocInfo::oop_type:
635 // handled by do_unloading_oops below
636 break;
637
638 case relocInfo::metadata_type:
639 break; // nothing to do.
640
641 default:
642 break;
643 }
644 }
645
646 if (do_unloading_oops(low_boundary, is_alive, unloading_occurred)) {
647 return postponed;
648 }
649
650 #if INCLUDE_JVMCI
651 if (do_unloading_jvmci(is_alive, unloading_occurred)) {
652 return postponed;
653 }
654 #endif
655
656 // Ensure that all metadata is still alive
657 verify_metadata_loaders(low_boundary, is_alive);
658
659 return postponed;
660 }
661
662 void CompiledMethod::do_unloading_parallel_postponed(BoolObjectClosure* is_alive, bool unloading_occurred) {
663 ResourceMark rm;
664
665 // Make sure the oop's ready to receive visitors
666 assert(!is_zombie(),
667 "should not call follow on zombie nmethod");
668
669 // If the method is not entrant then a JMP is plastered over the
670 // first few bytes. If an oop in the old code was there, that oop
671 // should not get GC'd. Skip the first few bytes of oops on
672 // not-entrant methods.
673 address low_boundary = verified_entry_point();
674 if (is_not_entrant()) {
675 low_boundary += NativeJump::instruction_size;
676 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
677 // (See comment above.)
678 }
679
680 RelocIterator iter(this, low_boundary);
681 while(iter.next()) {
682
683 switch (iter.type()) {
684
685 case relocInfo::virtual_call_type:
686 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
687 break;
688
689 case relocInfo::opt_virtual_call_type:
690 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
691 break;
692
693 case relocInfo::static_call_type:
694 clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
695 break;
696
697 default:
698 break;
699 }
700 }
701 }