1 /*
2 * Copyright (c) 1997, 2024, 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 "asm/assembler.inline.hpp"
27 #include "code/codeCache.hpp"
28 #include "code/compiledIC.hpp"
29 #include "code/dependencies.hpp"
30 #include "code/nativeInst.hpp"
31 #include "code/nmethod.inline.hpp"
32 #include "code/scopeDesc.hpp"
33 #include "code/SCCache.hpp"
34 #include "compiler/abstractCompiler.hpp"
35 #include "compiler/compilationLog.hpp"
36 #include "compiler/compileBroker.hpp"
37 #include "compiler/compileLog.hpp"
38 #include "compiler/compileTask.hpp"
39 #include "compiler/compilerDirectives.hpp"
40 #include "compiler/compilerOracle.hpp"
41 #include "compiler/directivesParser.hpp"
42 #include "compiler/disassembler.hpp"
43 #include "compiler/oopMap.inline.hpp"
44 #include "gc/shared/barrierSet.hpp"
45 #include "gc/shared/barrierSetNMethod.hpp"
46 #include "gc/shared/classUnloadingContext.hpp"
47 #include "gc/shared/collectedHeap.hpp"
48 #include "interpreter/bytecode.inline.hpp"
49 #include "jvm.h"
50 #include "logging/log.hpp"
51 #include "logging/logStream.hpp"
52 #include "memory/allocation.inline.hpp"
53 #include "memory/resourceArea.hpp"
54 #include "memory/universe.hpp"
55 #include "oops/access.inline.hpp"
56 #include "oops/klass.inline.hpp"
57 #include "oops/method.inline.hpp"
58 #include "oops/methodData.hpp"
59 #include "oops/oop.inline.hpp"
60 #include "oops/weakHandle.inline.hpp"
61 #include "prims/jvmtiImpl.hpp"
62 #include "prims/jvmtiThreadState.hpp"
63 #include "prims/methodHandles.hpp"
64 #include "runtime/continuation.hpp"
65 #include "runtime/atomic.hpp"
66 #include "runtime/deoptimization.hpp"
67 #include "runtime/flags/flagSetting.hpp"
68 #include "runtime/frame.inline.hpp"
69 #include "runtime/handles.inline.hpp"
70 #include "runtime/jniHandles.inline.hpp"
71 #include "runtime/orderAccess.hpp"
72 #include "runtime/os.hpp"
73 #include "runtime/safepointVerifiers.hpp"
74 #include "runtime/serviceThread.hpp"
75 #include "runtime/sharedRuntime.hpp"
76 #include "runtime/signature.hpp"
77 #include "runtime/threadWXSetters.inline.hpp"
78 #include "runtime/vmThread.hpp"
79 #include "utilities/align.hpp"
80 #include "utilities/copy.hpp"
81 #include "utilities/dtrace.hpp"
82 #include "utilities/events.hpp"
83 #include "utilities/globalDefinitions.hpp"
84 #include "utilities/resourceHash.hpp"
85 #include "utilities/xmlstream.hpp"
86 #if INCLUDE_JVMCI
87 #include "jvmci/jvmciRuntime.hpp"
88 #endif
89
90 #ifdef DTRACE_ENABLED
91
92 // Only bother with this argument setup if dtrace is available
93
94 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
95 { \
96 Method* m = (method); \
97 if (m != nullptr) { \
98 Symbol* klass_name = m->klass_name(); \
99 Symbol* name = m->name(); \
100 Symbol* signature = m->signature(); \
101 HOTSPOT_COMPILED_METHOD_UNLOAD( \
102 (char *) klass_name->bytes(), klass_name->utf8_length(), \
103 (char *) name->bytes(), name->utf8_length(), \
104 (char *) signature->bytes(), signature->utf8_length()); \
105 } \
106 }
107
108 #else // ndef DTRACE_ENABLED
109
110 #define DTRACE_METHOD_UNLOAD_PROBE(method)
111
112 #endif
113
114 // Cast from int value to narrow type
115 #define CHECKED_CAST(result, T, thing) \
116 result = static_cast<T>(thing); \
117 assert(static_cast<int>(result) == thing, "failed: %d != %d", static_cast<int>(result), thing);
118
119 //---------------------------------------------------------------------------------
120 // NMethod statistics
121 // They are printed under various flags, including:
122 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
123 // (In the latter two cases, they like other stats are printed to the log only.)
124
125 #ifndef PRODUCT
126 // These variables are put into one block to reduce relocations
127 // and make it simpler to print from the debugger.
128 struct java_nmethod_stats_struct {
129 uint nmethod_count;
130 uint total_nm_size;
131 uint total_immut_size;
132 uint relocation_size;
133 uint consts_size;
134 uint insts_size;
135 uint inline_insts_size;
136 uint stub_size;
137 uint oops_size;
138 uint metadata_size;
139 uint dependencies_size;
140 uint nul_chk_table_size;
141 uint handler_table_size;
142 uint scopes_pcs_size;
143 uint scopes_data_size;
144 #if INCLUDE_JVMCI
145 uint speculations_size;
146 uint jvmci_data_size;
147 #endif
148
149 void note_nmethod(nmethod* nm) {
150 nmethod_count += 1;
151 total_nm_size += nm->size();
152 total_immut_size += nm->immutable_data_size();
153 relocation_size += nm->relocation_size();
154 consts_size += nm->consts_size();
155 insts_size += nm->insts_size();
156 inline_insts_size += nm->inline_insts_size();
157 stub_size += nm->stub_size();
158 oops_size += nm->oops_size();
159 metadata_size += nm->metadata_size();
160 scopes_data_size += nm->scopes_data_size();
161 scopes_pcs_size += nm->scopes_pcs_size();
162 dependencies_size += nm->dependencies_size();
163 handler_table_size += nm->handler_table_size();
164 nul_chk_table_size += nm->nul_chk_table_size();
165 #if INCLUDE_JVMCI
166 speculations_size += nm->speculations_size();
167 jvmci_data_size += nm->jvmci_data_size();
168 #endif
169 }
170 void print_nmethod_stats(const char* name) {
171 if (nmethod_count == 0) return;
172 tty->print_cr("Statistics for %u bytecoded nmethods for %s:", nmethod_count, name);
173 uint total_size = total_nm_size + total_immut_size;
174 if (total_nm_size != 0) {
175 tty->print_cr(" total size = %u (100%%)", total_size);
176 tty->print_cr(" in CodeCache = %u (%f%%)", total_nm_size, (total_nm_size * 100.0f)/total_size);
177 }
178 uint header_size = (uint)(nmethod_count * sizeof(nmethod));
179 if (nmethod_count != 0) {
180 tty->print_cr(" header = %u (%f%%)", header_size, (header_size * 100.0f)/total_nm_size);
181 }
182 if (relocation_size != 0) {
183 tty->print_cr(" relocation = %u (%f%%)", relocation_size, (relocation_size * 100.0f)/total_nm_size);
184 }
185 if (consts_size != 0) {
186 tty->print_cr(" constants = %u (%f%%)", consts_size, (consts_size * 100.0f)/total_nm_size);
187 }
188 if (insts_size != 0) {
189 tty->print_cr(" main code = %u (%f%%)", insts_size, (insts_size * 100.0f)/total_nm_size);
190 }
191 if (inline_insts_size != 0) {
192 tty->print_cr(" inline code = %u (%f%%)", inline_insts_size, (inline_insts_size * 100.0f)/total_nm_size);
193 }
194 if (stub_size != 0) {
195 tty->print_cr(" stub code = %u (%f%%)", stub_size, (stub_size * 100.0f)/total_nm_size);
196 }
197 if (oops_size != 0) {
198 tty->print_cr(" oops = %u (%f%%)", oops_size, (oops_size * 100.0f)/total_nm_size);
199 }
200 if (metadata_size != 0) {
201 tty->print_cr(" metadata = %u (%f%%)", metadata_size, (metadata_size * 100.0f)/total_nm_size);
202 }
203 #if INCLUDE_JVMCI
204 if (jvmci_data_size != 0) {
205 tty->print_cr(" JVMCI data = %u (%f%%)", jvmci_data_size, (jvmci_data_size * 100.0f)/total_nm_size);
206 }
207 #endif
208 if (total_immut_size != 0) {
209 tty->print_cr(" immutable data = %u (%f%%)", total_immut_size, (total_immut_size * 100.0f)/total_size);
210 }
211 if (dependencies_size != 0) {
212 tty->print_cr(" dependencies = %u (%f%%)", dependencies_size, (dependencies_size * 100.0f)/total_immut_size);
213 }
214 if (nul_chk_table_size != 0) {
215 tty->print_cr(" nul chk table = %u (%f%%)", nul_chk_table_size, (nul_chk_table_size * 100.0f)/total_immut_size);
216 }
217 if (handler_table_size != 0) {
218 tty->print_cr(" handler table = %u (%f%%)", handler_table_size, (handler_table_size * 100.0f)/total_immut_size);
219 }
220 if (scopes_pcs_size != 0) {
221 tty->print_cr(" scopes pcs = %u (%f%%)", scopes_pcs_size, (scopes_pcs_size * 100.0f)/total_immut_size);
222 }
223 if (scopes_data_size != 0) {
224 tty->print_cr(" scopes data = %u (%f%%)", scopes_data_size, (scopes_data_size * 100.0f)/total_immut_size);
225 }
226 #if INCLUDE_JVMCI
227 if (speculations_size != 0) {
228 tty->print_cr(" speculations = %u (%f%%)", speculations_size, (speculations_size * 100.0f)/total_immut_size);
229 }
230 #endif
231 }
232 };
233
234 struct native_nmethod_stats_struct {
235 uint native_nmethod_count;
236 uint native_total_size;
237 uint native_relocation_size;
238 uint native_insts_size;
239 uint native_oops_size;
240 uint native_metadata_size;
241 void note_native_nmethod(nmethod* nm) {
242 native_nmethod_count += 1;
243 native_total_size += nm->size();
244 native_relocation_size += nm->relocation_size();
245 native_insts_size += nm->insts_size();
246 native_oops_size += nm->oops_size();
247 native_metadata_size += nm->metadata_size();
248 }
249 void print_native_nmethod_stats() {
250 if (native_nmethod_count == 0) return;
251 tty->print_cr("Statistics for %u native nmethods:", native_nmethod_count);
252 if (native_total_size != 0) tty->print_cr(" N. total size = %u", native_total_size);
253 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %u", native_relocation_size);
254 if (native_insts_size != 0) tty->print_cr(" N. main code = %u", native_insts_size);
255 if (native_oops_size != 0) tty->print_cr(" N. oops = %u", native_oops_size);
256 if (native_metadata_size != 0) tty->print_cr(" N. metadata = %u", native_metadata_size);
257 }
258 };
259
260 struct pc_nmethod_stats_struct {
261 uint pc_desc_init; // number of initialization of cache (= number of caches)
262 uint pc_desc_queries; // queries to nmethod::find_pc_desc
263 uint pc_desc_approx; // number of those which have approximate true
264 uint pc_desc_repeats; // number of _pc_descs[0] hits
265 uint pc_desc_hits; // number of LRU cache hits
266 uint pc_desc_tests; // total number of PcDesc examinations
267 uint pc_desc_searches; // total number of quasi-binary search steps
268 uint pc_desc_adds; // number of LUR cache insertions
269
270 void print_pc_stats() {
271 tty->print_cr("PcDesc Statistics: %u queries, %.2f comparisons per query",
272 pc_desc_queries,
273 (double)(pc_desc_tests + pc_desc_searches)
274 / pc_desc_queries);
275 tty->print_cr(" caches=%d queries=%u/%u, hits=%u+%u, tests=%u+%u, adds=%u",
276 pc_desc_init,
277 pc_desc_queries, pc_desc_approx,
278 pc_desc_repeats, pc_desc_hits,
279 pc_desc_tests, pc_desc_searches, pc_desc_adds);
280 }
281 };
282
283 #ifdef COMPILER1
284 static java_nmethod_stats_struct c1_java_nmethod_stats;
285 #endif
286 #ifdef COMPILER2
287 static java_nmethod_stats_struct c2_java_nmethod_stats;
288 #endif
289 #if INCLUDE_JVMCI
290 static java_nmethod_stats_struct jvmci_java_nmethod_stats;
291 #endif
292 static java_nmethod_stats_struct unknown_java_nmethod_stats;
293
294 static native_nmethod_stats_struct native_nmethod_stats;
295 static pc_nmethod_stats_struct pc_nmethod_stats;
296
297 static void note_java_nmethod(nmethod* nm) {
298 #ifdef COMPILER1
299 if (nm->is_compiled_by_c1()) {
300 c1_java_nmethod_stats.note_nmethod(nm);
301 } else
302 #endif
303 #ifdef COMPILER2
304 if (nm->is_compiled_by_c2()) {
305 c2_java_nmethod_stats.note_nmethod(nm);
306 } else
307 #endif
308 #if INCLUDE_JVMCI
309 if (nm->is_compiled_by_jvmci()) {
310 jvmci_java_nmethod_stats.note_nmethod(nm);
311 } else
312 #endif
313 {
314 unknown_java_nmethod_stats.note_nmethod(nm);
315 }
316 }
317 #endif // !PRODUCT
318
319 //---------------------------------------------------------------------------------
320
321
322 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
323 assert(pc != nullptr, "Must be non null");
324 assert(exception.not_null(), "Must be non null");
325 assert(handler != nullptr, "Must be non null");
326
327 _count = 0;
328 _exception_type = exception->klass();
329 _next = nullptr;
330 _purge_list_next = nullptr;
331
332 add_address_and_handler(pc,handler);
333 }
334
335
336 address ExceptionCache::match(Handle exception, address pc) {
337 assert(pc != nullptr,"Must be non null");
338 assert(exception.not_null(),"Must be non null");
339 if (exception->klass() == exception_type()) {
340 return (test_address(pc));
341 }
342
343 return nullptr;
344 }
345
346
347 bool ExceptionCache::match_exception_with_space(Handle exception) {
348 assert(exception.not_null(),"Must be non null");
349 if (exception->klass() == exception_type() && count() < cache_size) {
350 return true;
351 }
352 return false;
353 }
354
355
356 address ExceptionCache::test_address(address addr) {
357 int limit = count();
358 for (int i = 0; i < limit; i++) {
359 if (pc_at(i) == addr) {
360 return handler_at(i);
361 }
362 }
363 return nullptr;
364 }
365
366
367 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
368 if (test_address(addr) == handler) return true;
369
370 int index = count();
371 if (index < cache_size) {
372 set_pc_at(index, addr);
373 set_handler_at(index, handler);
374 increment_count();
375 return true;
376 }
377 return false;
378 }
379
380 ExceptionCache* ExceptionCache::next() {
381 return Atomic::load(&_next);
382 }
383
384 void ExceptionCache::set_next(ExceptionCache *ec) {
385 Atomic::store(&_next, ec);
386 }
387
388 //-----------------------------------------------------------------------------
389
390
391 // Helper used by both find_pc_desc methods.
392 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
393 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests);
394 if (!approximate) {
395 return pc->pc_offset() == pc_offset;
396 } else {
397 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
398 }
399 }
400
401 void PcDescCache::init_to(PcDesc* initial_pc_desc) {
402 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_init);
403 // initialize the cache by filling it with benign (non-null) values
404 assert(initial_pc_desc != nullptr && initial_pc_desc->pc_offset() == PcDesc::lower_offset_limit,
405 "must start with a sentinel");
406 for (int i = 0; i < cache_size; i++) {
407 _pc_descs[i] = initial_pc_desc;
408 }
409 }
410
411 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
412 // Note: one might think that caching the most recently
413 // read value separately would be a win, but one would be
414 // wrong. When many threads are updating it, the cache
415 // line it's in would bounce between caches, negating
416 // any benefit.
417
418 // In order to prevent race conditions do not load cache elements
419 // repeatedly, but use a local copy:
420 PcDesc* res;
421
422 // Step one: Check the most recently added value.
423 res = _pc_descs[0];
424 assert(res != nullptr, "PcDesc cache should be initialized already");
425
426 // Approximate only here since PcDescContainer::find_pc_desc() checked for exact case.
427 if (approximate && match_desc(res, pc_offset, approximate)) {
428 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats);
429 return res;
430 }
431
432 // Step two: Check the rest of the LRU cache.
433 for (int i = 1; i < cache_size; ++i) {
434 res = _pc_descs[i];
435 if (res->pc_offset() < 0) break; // optimization: skip empty cache
436 if (match_desc(res, pc_offset, approximate)) {
437 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits);
438 return res;
439 }
440 }
441
442 // Report failure.
443 return nullptr;
444 }
445
446 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
447 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds);
448 // Update the LRU cache by shifting pc_desc forward.
449 for (int i = 0; i < cache_size; i++) {
450 PcDesc* next = _pc_descs[i];
451 _pc_descs[i] = pc_desc;
452 pc_desc = next;
453 }
454 }
455
456 // adjust pcs_size so that it is a multiple of both oopSize and
457 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
458 // of oopSize, then 2*sizeof(PcDesc) is)
459 static int adjust_pcs_size(int pcs_size) {
460 int nsize = align_up(pcs_size, oopSize);
461 if ((nsize % sizeof(PcDesc)) != 0) {
462 nsize = pcs_size + sizeof(PcDesc);
463 }
464 assert((nsize % oopSize) == 0, "correct alignment");
465 return nsize;
466 }
467
468 bool nmethod::is_method_handle_return(address return_pc) {
469 if (!has_method_handle_invokes()) return false;
470 PcDesc* pd = pc_desc_at(return_pc);
471 if (pd == nullptr)
472 return false;
473 return pd->is_method_handle_invoke();
474 }
475
476 // Returns a string version of the method state.
477 const char* nmethod::state() const {
478 int state = get_state();
479 switch (state) {
480 case not_installed:
481 return "not installed";
482 case in_use:
483 return "in use";
484 case not_entrant:
485 return "not_entrant";
486 default:
487 fatal("unexpected method state: %d", state);
488 return nullptr;
489 }
490 }
491
492 void nmethod::set_deoptimized_done() {
493 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
494 if (_deoptimization_status != deoptimize_done) { // can't go backwards
495 Atomic::store(&_deoptimization_status, deoptimize_done);
496 }
497 }
498
499 ExceptionCache* nmethod::exception_cache_acquire() const {
500 return Atomic::load_acquire(&_exception_cache);
501 }
502
503 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
504 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
505 assert(new_entry != nullptr,"Must be non null");
506 assert(new_entry->next() == nullptr, "Must be null");
507
508 for (;;) {
509 ExceptionCache *ec = exception_cache();
510 if (ec != nullptr) {
511 Klass* ex_klass = ec->exception_type();
512 if (!ex_klass->is_loader_alive()) {
513 // We must guarantee that entries are not inserted with new next pointer
514 // edges to ExceptionCache entries with dead klasses, due to bad interactions
515 // with concurrent ExceptionCache cleanup. Therefore, the inserts roll
516 // the head pointer forward to the first live ExceptionCache, so that the new
517 // next pointers always point at live ExceptionCaches, that are not removed due
518 // to concurrent ExceptionCache cleanup.
519 ExceptionCache* next = ec->next();
520 if (Atomic::cmpxchg(&_exception_cache, ec, next) == ec) {
521 CodeCache::release_exception_cache(ec);
522 }
523 continue;
524 }
525 ec = exception_cache();
526 if (ec != nullptr) {
527 new_entry->set_next(ec);
528 }
529 }
530 if (Atomic::cmpxchg(&_exception_cache, ec, new_entry) == ec) {
531 return;
532 }
533 }
534 }
535
536 void nmethod::clean_exception_cache() {
537 // For each nmethod, only a single thread may call this cleanup function
538 // at the same time, whether called in STW cleanup or concurrent cleanup.
539 // Note that if the GC is processing exception cache cleaning in a concurrent phase,
540 // then a single writer may contend with cleaning up the head pointer to the
541 // first ExceptionCache node that has a Klass* that is alive. That is fine,
542 // as long as there is no concurrent cleanup of next pointers from concurrent writers.
543 // And the concurrent writers do not clean up next pointers, only the head.
544 // Also note that concurrent readers will walk through Klass* pointers that are not
545 // alive. That does not cause ABA problems, because Klass* is deleted after
546 // a handshake with all threads, after all stale ExceptionCaches have been
547 // unlinked. That is also when the CodeCache::exception_cache_purge_list()
548 // is deleted, with all ExceptionCache entries that were cleaned concurrently.
549 // That similarly implies that CAS operations on ExceptionCache entries do not
550 // suffer from ABA problems as unlinking and deletion is separated by a global
551 // handshake operation.
552 ExceptionCache* prev = nullptr;
553 ExceptionCache* curr = exception_cache_acquire();
554
555 while (curr != nullptr) {
556 ExceptionCache* next = curr->next();
557
558 if (!curr->exception_type()->is_loader_alive()) {
559 if (prev == nullptr) {
560 // Try to clean head; this is contended by concurrent inserts, that
561 // both lazily clean the head, and insert entries at the head. If
562 // the CAS fails, the operation is restarted.
563 if (Atomic::cmpxchg(&_exception_cache, curr, next) != curr) {
564 prev = nullptr;
565 curr = exception_cache_acquire();
566 continue;
567 }
568 } else {
569 // It is impossible to during cleanup connect the next pointer to
570 // an ExceptionCache that has not been published before a safepoint
571 // prior to the cleanup. Therefore, release is not required.
572 prev->set_next(next);
573 }
574 // prev stays the same.
575
576 CodeCache::release_exception_cache(curr);
577 } else {
578 prev = curr;
579 }
580
581 curr = next;
582 }
583 }
584
585 // public method for accessing the exception cache
586 // These are the public access methods.
587 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
588 // We never grab a lock to read the exception cache, so we may
589 // have false negatives. This is okay, as it can only happen during
590 // the first few exception lookups for a given nmethod.
591 ExceptionCache* ec = exception_cache_acquire();
592 while (ec != nullptr) {
593 address ret_val;
594 if ((ret_val = ec->match(exception,pc)) != nullptr) {
595 return ret_val;
596 }
597 ec = ec->next();
598 }
599 return nullptr;
600 }
601
602 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
603 // There are potential race conditions during exception cache updates, so we
604 // must own the ExceptionCache_lock before doing ANY modifications. Because
605 // we don't lock during reads, it is possible to have several threads attempt
606 // to update the cache with the same data. We need to check for already inserted
607 // copies of the current data before adding it.
608
609 MutexLocker ml(ExceptionCache_lock);
610 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
611
612 if (target_entry == nullptr || !target_entry->add_address_and_handler(pc,handler)) {
613 target_entry = new ExceptionCache(exception,pc,handler);
614 add_exception_cache_entry(target_entry);
615 }
616 }
617
618 // private method for handling exception cache
619 // These methods are private, and used to manipulate the exception cache
620 // directly.
621 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
622 ExceptionCache* ec = exception_cache_acquire();
623 while (ec != nullptr) {
624 if (ec->match_exception_with_space(exception)) {
625 return ec;
626 }
627 ec = ec->next();
628 }
629 return nullptr;
630 }
631
632 bool nmethod::is_at_poll_return(address pc) {
633 RelocIterator iter(this, pc, pc+1);
634 while (iter.next()) {
635 if (iter.type() == relocInfo::poll_return_type)
636 return true;
637 }
638 return false;
639 }
640
641
642 bool nmethod::is_at_poll_or_poll_return(address pc) {
643 RelocIterator iter(this, pc, pc+1);
644 while (iter.next()) {
645 relocInfo::relocType t = iter.type();
646 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
647 return true;
648 }
649 return false;
650 }
651
652 void nmethod::verify_oop_relocations() {
653 // Ensure sure that the code matches the current oop values
654 RelocIterator iter(this, nullptr, nullptr);
655 while (iter.next()) {
656 if (iter.type() == relocInfo::oop_type) {
657 oop_Relocation* reloc = iter.oop_reloc();
658 if (!reloc->oop_is_immediate()) {
659 reloc->verify_oop_relocation();
660 }
661 }
662 }
663 }
664
665
666 ScopeDesc* nmethod::scope_desc_at(address pc) {
667 PcDesc* pd = pc_desc_at(pc);
668 guarantee(pd != nullptr, "scope must be present");
669 return new ScopeDesc(this, pd);
670 }
671
672 ScopeDesc* nmethod::scope_desc_near(address pc) {
673 PcDesc* pd = pc_desc_near(pc);
674 guarantee(pd != nullptr, "scope must be present");
675 return new ScopeDesc(this, pd);
676 }
677
678 address nmethod::oops_reloc_begin() const {
679 // If the method is not entrant then a JMP is plastered over the
680 // first few bytes. If an oop in the old code was there, that oop
681 // should not get GC'd. Skip the first few bytes of oops on
682 // not-entrant methods.
683 if (frame_complete_offset() != CodeOffsets::frame_never_safe &&
684 code_begin() + frame_complete_offset() >
685 verified_entry_point() + NativeJump::instruction_size)
686 {
687 // If we have a frame_complete_offset after the native jump, then there
688 // is no point trying to look for oops before that. This is a requirement
689 // for being allowed to scan oops concurrently.
690 return code_begin() + frame_complete_offset();
691 }
692
693 // It is not safe to read oops concurrently using entry barriers, if their
694 // location depend on whether the nmethod is entrant or not.
695 // assert(BarrierSet::barrier_set()->barrier_set_nmethod() == nullptr, "Not safe oop scan");
696
697 address low_boundary = verified_entry_point();
698 if (!is_in_use()) {
699 low_boundary += NativeJump::instruction_size;
700 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
701 // This means that the low_boundary is going to be a little too high.
702 // This shouldn't matter, since oops of non-entrant methods are never used.
703 // In fact, why are we bothering to look at oops in a non-entrant method??
704 }
705 return low_boundary;
706 }
707
708 // Method that knows how to preserve outgoing arguments at call. This method must be
709 // called with a frame corresponding to a Java invoke
710 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
711 if (method() == nullptr) {
712 return;
713 }
714
715 // handle the case of an anchor explicitly set in continuation code that doesn't have a callee
716 JavaThread* thread = reg_map->thread();
717 if (thread->has_last_Java_frame() && fr.sp() == thread->last_Java_sp()) {
718 return;
719 }
720
721 if (!method()->is_native()) {
722 address pc = fr.pc();
723 bool has_receiver, has_appendix;
724 Symbol* signature;
725
726 // The method attached by JIT-compilers should be used, if present.
727 // Bytecode can be inaccurate in such case.
728 Method* callee = attached_method_before_pc(pc);
729 if (callee != nullptr) {
730 has_receiver = !(callee->access_flags().is_static());
731 has_appendix = false;
732 signature = callee->signature();
733 } else {
734 SimpleScopeDesc ssd(this, pc);
735
736 Bytecode_invoke call(methodHandle(Thread::current(), ssd.method()), ssd.bci());
737 has_receiver = call.has_receiver();
738 has_appendix = call.has_appendix();
739 signature = call.signature();
740 }
741
742 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
743 } else if (method()->is_continuation_enter_intrinsic()) {
744 // This method only calls Continuation.enter()
745 Symbol* signature = vmSymbols::continuationEnter_signature();
746 fr.oops_compiled_arguments_do(signature, false, false, reg_map, f);
747 }
748 }
749
750 Method* nmethod::attached_method(address call_instr) {
751 assert(code_contains(call_instr), "not part of the nmethod");
752 RelocIterator iter(this, call_instr, call_instr + 1);
753 while (iter.next()) {
754 if (iter.addr() == call_instr) {
755 switch(iter.type()) {
756 case relocInfo::static_call_type: return iter.static_call_reloc()->method_value();
757 case relocInfo::opt_virtual_call_type: return iter.opt_virtual_call_reloc()->method_value();
758 case relocInfo::virtual_call_type: return iter.virtual_call_reloc()->method_value();
759 default: break;
760 }
761 }
762 }
763 return nullptr; // not found
764 }
765
766 Method* nmethod::attached_method_before_pc(address pc) {
767 if (NativeCall::is_call_before(pc)) {
768 NativeCall* ncall = nativeCall_before(pc);
769 return attached_method(ncall->instruction_address());
770 }
771 return nullptr; // not a call
772 }
773
774 void nmethod::clear_inline_caches() {
775 assert(SafepointSynchronize::is_at_safepoint(), "clearing of IC's only allowed at safepoint");
776 RelocIterator iter(this);
777 while (iter.next()) {
778 iter.reloc()->clear_inline_cache();
779 }
780 }
781
782 #ifdef ASSERT
783 // Check class_loader is alive for this bit of metadata.
784 class CheckClass : public MetadataClosure {
785 void do_metadata(Metadata* md) {
786 Klass* klass = nullptr;
787 if (md->is_klass()) {
788 klass = ((Klass*)md);
789 } else if (md->is_method()) {
790 klass = ((Method*)md)->method_holder();
791 } else if (md->is_methodData()) {
792 klass = ((MethodData*)md)->method()->method_holder();
793 } else if (md->is_methodCounters()) {
794 klass = ((MethodCounters*)md)->method()->method_holder();
795 } else {
796 md->print();
797 ShouldNotReachHere();
798 }
799 assert(klass->is_loader_alive(), "must be alive");
800 }
801 };
802 #endif // ASSERT
803
804
805 static void clean_ic_if_metadata_is_dead(CompiledIC *ic) {
806 ic->clean_metadata();
807 }
808
809 // Clean references to unloaded nmethods at addr from this one, which is not unloaded.
810 template <typename CallsiteT>
811 static void clean_if_nmethod_is_unloaded(CallsiteT* callsite, nmethod* from,
812 bool clean_all) {
813 CodeBlob* cb = CodeCache::find_blob(callsite->destination());
814 if (!cb->is_nmethod()) {
815 return;
816 }
817 nmethod* nm = cb->as_nmethod();
818 if (clean_all || !nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
819 callsite->set_to_clean();
820 }
821 }
822
823 // Cleans caches in nmethods that point to either classes that are unloaded
824 // or nmethods that are unloaded.
825 //
826 // Can be called either in parallel by G1 currently or after all
827 // nmethods are unloaded. Return postponed=true in the parallel case for
828 // inline caches found that point to nmethods that are not yet visited during
829 // the do_unloading walk.
830 void nmethod::unload_nmethod_caches(bool unloading_occurred) {
831 ResourceMark rm;
832
833 // Exception cache only needs to be called if unloading occurred
834 if (unloading_occurred) {
835 clean_exception_cache();
836 }
837
838 cleanup_inline_caches_impl(unloading_occurred, false);
839
840 #ifdef ASSERT
841 // Check that the metadata embedded in the nmethod is alive
842 CheckClass check_class;
843 metadata_do(&check_class);
844 #endif
845 }
846
847 void nmethod::run_nmethod_entry_barrier() {
848 BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
849 if (bs_nm != nullptr) {
850 // We want to keep an invariant that nmethods found through iterations of a Thread's
851 // nmethods found in safepoints have gone through an entry barrier and are not armed.
852 // By calling this nmethod entry barrier, it plays along and acts
853 // like any other nmethod found on the stack of a thread (fewer surprises).
854 nmethod* nm = this;
855 if (bs_nm->is_armed(nm)) {
856 bool alive = bs_nm->nmethod_entry_barrier(nm);
857 assert(alive, "should be alive");
858 }
859 }
860 }
861
862 // Only called by whitebox test
863 void nmethod::cleanup_inline_caches_whitebox() {
864 assert_locked_or_safepoint(CodeCache_lock);
865 CompiledICLocker ic_locker(this);
866 cleanup_inline_caches_impl(false /* unloading_occurred */, true /* clean_all */);
867 }
868
869 address* nmethod::orig_pc_addr(const frame* fr) {
870 return (address*) ((address)fr->unextended_sp() + orig_pc_offset());
871 }
872
873 // Called to clean up after class unloading for live nmethods
874 void nmethod::cleanup_inline_caches_impl(bool unloading_occurred, bool clean_all) {
875 assert(CompiledICLocker::is_safe(this), "mt unsafe call");
876 ResourceMark rm;
877
878 // Find all calls in an nmethod and clear the ones that point to bad nmethods.
879 RelocIterator iter(this, oops_reloc_begin());
880 bool is_in_static_stub = false;
881 while(iter.next()) {
882
883 switch (iter.type()) {
884
885 case relocInfo::virtual_call_type:
886 if (unloading_occurred) {
887 // If class unloading occurred we first clear ICs where the cached metadata
888 // is referring to an unloaded klass or method.
889 clean_ic_if_metadata_is_dead(CompiledIC_at(&iter));
890 }
891
892 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), this, clean_all);
893 break;
894
895 case relocInfo::opt_virtual_call_type:
896 case relocInfo::static_call_type:
897 clean_if_nmethod_is_unloaded(CompiledDirectCall::at(iter.reloc()), this, clean_all);
898 break;
899
900 case relocInfo::static_stub_type: {
901 is_in_static_stub = true;
902 break;
903 }
904
905 case relocInfo::metadata_type: {
906 // Only the metadata relocations contained in static/opt virtual call stubs
907 // contains the Method* passed to c2i adapters. It is the only metadata
908 // relocation that needs to be walked, as it is the one metadata relocation
909 // that violates the invariant that all metadata relocations have an oop
910 // in the compiled method (due to deferred resolution and code patching).
911
912 // This causes dead metadata to remain in compiled methods that are not
913 // unloading. Unless these slippery metadata relocations of the static
914 // stubs are at least cleared, subsequent class redefinition operations
915 // will access potentially free memory, and JavaThread execution
916 // concurrent to class unloading may call c2i adapters with dead methods.
917 if (!is_in_static_stub) {
918 // The first metadata relocation after a static stub relocation is the
919 // metadata relocation of the static stub used to pass the Method* to
920 // c2i adapters.
921 continue;
922 }
923 is_in_static_stub = false;
924 if (is_unloading()) {
925 // If the nmethod itself is dying, then it may point at dead metadata.
926 // Nobody should follow that metadata; it is strictly unsafe.
927 continue;
928 }
929 metadata_Relocation* r = iter.metadata_reloc();
930 Metadata* md = r->metadata_value();
931 if (md != nullptr && md->is_method()) {
932 Method* method = static_cast<Method*>(md);
933 if (!method->method_holder()->is_loader_alive()) {
934 Atomic::store(r->metadata_addr(), (Method*)nullptr);
935
936 if (!r->metadata_is_immediate()) {
937 r->fix_metadata_relocation();
938 }
939 }
940 }
941 break;
942 }
943
944 default:
945 break;
946 }
947 }
948 }
949
950 address nmethod::continuation_for_implicit_exception(address pc, bool for_div0_check) {
951 // Exception happened outside inline-cache check code => we are inside
952 // an active nmethod => use cpc to determine a return address
953 int exception_offset = int(pc - code_begin());
954 int cont_offset = ImplicitExceptionTable(this).continuation_offset( exception_offset );
955 #ifdef ASSERT
956 if (cont_offset == 0) {
957 Thread* thread = Thread::current();
958 ResourceMark rm(thread);
959 CodeBlob* cb = CodeCache::find_blob(pc);
960 assert(cb != nullptr && cb == this, "");
961
962 // Keep tty output consistent. To avoid ttyLocker, we buffer in stream, and print all at once.
963 stringStream ss;
964 ss.print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
965 print_on(&ss);
966 method()->print_codes_on(&ss);
967 print_code_on(&ss);
968 print_pcs_on(&ss);
969 tty->print("%s", ss.as_string()); // print all at once
970 }
971 #endif
972 if (cont_offset == 0) {
973 // Let the normal error handling report the exception
974 return nullptr;
975 }
976 if (cont_offset == exception_offset) {
977 #if INCLUDE_JVMCI
978 Deoptimization::DeoptReason deopt_reason = for_div0_check ? Deoptimization::Reason_div0_check : Deoptimization::Reason_null_check;
979 JavaThread *thread = JavaThread::current();
980 thread->set_jvmci_implicit_exception_pc(pc);
981 thread->set_pending_deoptimization(Deoptimization::make_trap_request(deopt_reason,
982 Deoptimization::Action_reinterpret));
983 return (SharedRuntime::deopt_blob()->implicit_exception_uncommon_trap());
984 #else
985 ShouldNotReachHere();
986 #endif
987 }
988 return code_begin() + cont_offset;
989 }
990
991 class HasEvolDependency : public MetadataClosure {
992 bool _has_evol_dependency;
993 public:
994 HasEvolDependency() : _has_evol_dependency(false) {}
995 void do_metadata(Metadata* md) {
996 if (md->is_method()) {
997 Method* method = (Method*)md;
998 if (method->is_old()) {
999 _has_evol_dependency = true;
1000 }
1001 }
1002 }
1003 bool has_evol_dependency() const { return _has_evol_dependency; }
1004 };
1005
1006 bool nmethod::has_evol_metadata() {
1007 // Check the metadata in relocIter and CompiledIC and also deoptimize
1008 // any nmethod that has reference to old methods.
1009 HasEvolDependency check_evol;
1010 metadata_do(&check_evol);
1011 if (check_evol.has_evol_dependency() && log_is_enabled(Debug, redefine, class, nmethod)) {
1012 ResourceMark rm;
1013 log_debug(redefine, class, nmethod)
1014 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on in nmethod metadata",
1015 _method->method_holder()->external_name(),
1016 _method->name()->as_C_string(),
1017 _method->signature()->as_C_string(),
1018 compile_id());
1019 }
1020 return check_evol.has_evol_dependency();
1021 }
1022
1023 int nmethod::total_size() const {
1024 return
1025 consts_size() +
1026 insts_size() +
1027 stub_size() +
1028 scopes_data_size() +
1029 scopes_pcs_size() +
1030 handler_table_size() +
1031 nul_chk_table_size();
1032 }
1033
1034 const char* nmethod::compile_kind() const {
1035 if (is_osr_method()) return "osr";
1036 if (method() != nullptr && is_native_method()) {
1037 if (method()->is_continuation_native_intrinsic()) {
1038 return "cnt";
1039 }
1040 return "c2n";
1041 }
1042 return nullptr;
1043 }
1044
1045 const char* nmethod::compiler_name() const {
1046 return compilertype2name(_compiler_type);
1047 }
1048
1049 #ifdef ASSERT
1050 class CheckForOopsClosure : public OopClosure {
1051 bool _found_oop = false;
1052 public:
1053 virtual void do_oop(oop* o) { _found_oop = true; }
1054 virtual void do_oop(narrowOop* o) { _found_oop = true; }
1055 bool found_oop() { return _found_oop; }
1056 };
1057 class CheckForMetadataClosure : public MetadataClosure {
1058 bool _found_metadata = false;
1059 Metadata* _ignore = nullptr;
1060 public:
1061 CheckForMetadataClosure(Metadata* ignore) : _ignore(ignore) {}
1062 virtual void do_metadata(Metadata* md) { if (md != _ignore) _found_metadata = true; }
1063 bool found_metadata() { return _found_metadata; }
1064 };
1065
1066 static void assert_no_oops_or_metadata(nmethod* nm) {
1067 if (nm == nullptr) return;
1068 assert(nm->oop_maps() == nullptr, "expectation");
1069
1070 CheckForOopsClosure cfo;
1071 nm->oops_do(&cfo);
1072 assert(!cfo.found_oop(), "no oops allowed");
1073
1074 // We allow an exception for the own Method, but require its class to be permanent.
1075 Method* own_method = nm->method();
1076 CheckForMetadataClosure cfm(/* ignore reference to own Method */ own_method);
1077 nm->metadata_do(&cfm);
1078 assert(!cfm.found_metadata(), "no metadata allowed");
1079
1080 assert(own_method->method_holder()->class_loader_data()->is_permanent_class_loader_data(),
1081 "Method's class needs to be permanent");
1082 }
1083 #endif
1084
1085 nmethod* nmethod::new_native_nmethod(const methodHandle& method,
1086 int compile_id,
1087 CodeBuffer *code_buffer,
1088 int vep_offset,
1089 int frame_complete,
1090 int frame_size,
1091 ByteSize basic_lock_owner_sp_offset,
1092 ByteSize basic_lock_sp_offset,
1093 OopMapSet* oop_maps,
1094 int exception_handler) {
1095 code_buffer->finalize_oop_references(method);
1096 // create nmethod
1097 nmethod* nm = nullptr;
1098 int native_nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
1099 {
1100 MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1101
1102 CodeOffsets offsets;
1103 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
1104 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
1105 if (exception_handler != -1) {
1106 offsets.set_value(CodeOffsets::Exceptions, exception_handler);
1107 }
1108
1109 // MH intrinsics are dispatch stubs which are compatible with NonNMethod space.
1110 // IsUnloadingBehaviour::is_unloading needs to handle them separately.
1111 bool allow_NonNMethod_space = method->can_be_allocated_in_NonNMethod_space();
1112 nm = new (native_nmethod_size, allow_NonNMethod_space)
1113 nmethod(method(), compiler_none, native_nmethod_size,
1114 compile_id, &offsets,
1115 code_buffer, frame_size,
1116 basic_lock_owner_sp_offset,
1117 basic_lock_sp_offset,
1118 oop_maps);
1119 DEBUG_ONLY( if (allow_NonNMethod_space) assert_no_oops_or_metadata(nm); )
1120 NOT_PRODUCT(if (nm != nullptr) native_nmethod_stats.note_native_nmethod(nm));
1121 }
1122
1123 if (nm != nullptr) {
1124 // verify nmethod
1125 debug_only(nm->verify();) // might block
1126
1127 nm->log_new_nmethod();
1128 }
1129 return nm;
1130 }
1131
1132 nmethod* nmethod::new_nmethod(const methodHandle& method,
1133 int compile_id,
1134 int entry_bci,
1135 CodeOffsets* offsets,
1136 int orig_pc_offset,
1137 DebugInformationRecorder* debug_info,
1138 Dependencies* dependencies,
1139 CodeBuffer* code_buffer, int frame_size,
1140 OopMapSet* oop_maps,
1141 ExceptionHandlerTable* handler_table,
1142 ImplicitExceptionTable* nul_chk_table,
1143 AbstractCompiler* compiler,
1144 CompLevel comp_level
1145 , SCCEntry* scc_entry
1146 #if INCLUDE_JVMCI
1147 , char* speculations,
1148 int speculations_len,
1149 JVMCINMethodData* jvmci_data
1150 #endif
1151 )
1152 {
1153 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
1154 code_buffer->finalize_oop_references(method);
1155 // create nmethod
1156 nmethod* nm = nullptr;
1157 int nmethod_size = CodeBlob::allocation_size(code_buffer, sizeof(nmethod));
1158 #if INCLUDE_JVMCI
1159 if (compiler->is_jvmci()) {
1160 nmethod_size += align_up(jvmci_data->size(), oopSize);
1161 }
1162 #endif
1163
1164 int immutable_data_size =
1165 adjust_pcs_size(debug_info->pcs_size())
1166 + align_up((int)dependencies->size_in_bytes(), oopSize)
1167 + align_up(handler_table->size_in_bytes() , oopSize)
1168 + align_up(nul_chk_table->size_in_bytes() , oopSize)
1169 #if INCLUDE_JVMCI
1170 + align_up(speculations_len , oopSize)
1171 #endif
1172 + align_up(debug_info->data_size() , oopSize);
1173
1174 // First, allocate space for immutable data in C heap.
1175 address immutable_data = nullptr;
1176 if (immutable_data_size > 0) {
1177 immutable_data = (address)os::malloc(immutable_data_size, mtCode);
1178 if (immutable_data == nullptr) {
1179 vm_exit_out_of_memory(immutable_data_size, OOM_MALLOC_ERROR, "nmethod: no space for immutable data");
1180 return nullptr;
1181 }
1182 }
1183 {
1184 MutexLocker mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1185
1186 nm = new (nmethod_size, comp_level)
1187 nmethod(method(), compiler->type(), nmethod_size, immutable_data_size,
1188 compile_id, entry_bci, immutable_data, offsets, orig_pc_offset,
1189 debug_info, dependencies, code_buffer, frame_size, oop_maps,
1190 handler_table, nul_chk_table, compiler, comp_level, scc_entry
1191 #if INCLUDE_JVMCI
1192 , speculations,
1193 speculations_len,
1194 jvmci_data
1195 #endif
1196 );
1197
1198 if (nm != nullptr) {
1199 // To make dependency checking during class loading fast, record
1200 // the nmethod dependencies in the classes it is dependent on.
1201 // This allows the dependency checking code to simply walk the
1202 // class hierarchy above the loaded class, checking only nmethods
1203 // which are dependent on those classes. The slow way is to
1204 // check every nmethod for dependencies which makes it linear in
1205 // the number of methods compiled. For applications with a lot
1206 // classes the slow way is too slow.
1207 for (Dependencies::DepStream deps(nm); deps.next(); ) {
1208 if (deps.type() == Dependencies::call_site_target_value) {
1209 // CallSite dependencies are managed on per-CallSite instance basis.
1210 oop call_site = deps.argument_oop(0);
1211 MethodHandles::add_dependent_nmethod(call_site, nm);
1212 } else {
1213 InstanceKlass* ik = deps.context_type();
1214 if (ik == nullptr) {
1215 continue; // ignore things like evol_method
1216 }
1217 // record this nmethod as dependent on this klass
1218 ik->add_dependent_nmethod(nm);
1219 }
1220 }
1221 NOT_PRODUCT(if (nm != nullptr) note_java_nmethod(nm));
1222 }
1223 }
1224 // Do verification and logging outside CodeCache_lock.
1225 if (nm != nullptr) {
1226
1227 #ifdef ASSERT
1228 LogTarget(Debug, scc, nmethod) log;
1229 if (log.is_enabled()) {
1230 LogStream out(log);
1231 out.print_cr("== new_nmethod 2");
1232 FlagSetting fs(PrintRelocations, true);
1233 nm->print(&out);
1234 nm->decode(&out);
1235 }
1236 #endif
1237
1238 // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
1239 DEBUG_ONLY(nm->verify();)
1240 nm->log_new_nmethod();
1241 }
1242 return nm;
1243 }
1244
1245 // Fill in default values for various fields
1246 void nmethod::init_defaults(CodeBuffer *code_buffer, CodeOffsets* offsets) {
1247 // avoid uninitialized fields, even for short time periods
1248 _exception_cache = nullptr;
1249 _gc_data = nullptr;
1250 _oops_do_mark_link = nullptr;
1251 _compiled_ic_data = nullptr;
1252
1253 #if INCLUDE_RTM_OPT
1254 _rtm_state = NoRTM;
1255 #endif
1256 _is_unloading_state = 0;
1257 _state = not_installed;
1258
1259 _has_unsafe_access = 0;
1260 _has_method_handle_invokes = 0;
1261 _has_wide_vectors = 0;
1262 _has_monitors = 0;
1263 _has_flushed_dependencies = 0;
1264 _is_unlinked = 0;
1265 _load_reported = 0; // jvmti state
1266 _preloaded = 0;
1267 _has_clinit_barriers = 0;
1268
1269 _used = false;
1270 _deoptimization_status = not_marked;
1271
1272 // SECT_CONSTS is first in code buffer so the offset should be 0.
1273 int consts_offset = code_buffer->total_offset_of(code_buffer->consts());
1274 assert(consts_offset == 0, "const_offset: %d", consts_offset);
1275
1276 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
1277
1278 CHECKED_CAST(_entry_offset, uint16_t, (offsets->value(CodeOffsets::Entry)));
1279 CHECKED_CAST(_verified_entry_offset, uint16_t, (offsets->value(CodeOffsets::Verified_Entry)));
1280
1281 int size = code_buffer->main_code_size();
1282 assert(size >= 0, "should be initialized");
1283 // Use instructions section size if it is 0 (e.g. native wrapper)
1284 if (size == 0) size = code_size(); // requires _stub_offset to be set
1285 assert(size <= code_size(), "incorrect size: %d > %d", size, code_size());
1286 _inline_insts_size = size - _verified_entry_offset
1287 - code_buffer->total_skipped_instructions_size();
1288 assert(_inline_insts_size >= 0, "sanity");
1289 }
1290
1291 // Post initialization
1292 void nmethod::post_init() {
1293 clear_unloading_state();
1294
1295 finalize_relocations();
1296
1297 Universe::heap()->register_nmethod(this);
1298 debug_only(Universe::heap()->verify_nmethod(this));
1299
1300 CodeCache::commit(this);
1301 }
1302
1303 // For native wrappers
1304 nmethod::nmethod(
1305 Method* method,
1306 CompilerType type,
1307 int nmethod_size,
1308 int compile_id,
1309 CodeOffsets* offsets,
1310 CodeBuffer* code_buffer,
1311 int frame_size,
1312 ByteSize basic_lock_owner_sp_offset,
1313 ByteSize basic_lock_sp_offset,
1314 OopMapSet* oop_maps )
1315 : CodeBlob("native nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
1316 offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
1317 _deoptimization_generation(0),
1318 _gc_epoch(CodeCache::gc_epoch()),
1319 _method(method),
1320 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
1321 _native_basic_lock_sp_offset(basic_lock_sp_offset)
1322 {
1323 {
1324 debug_only(NoSafepointVerifier nsv;)
1325 assert_locked_or_safepoint(CodeCache_lock);
1326
1327 init_defaults(code_buffer, offsets);
1328
1329 _osr_entry_point = nullptr;
1330 _pc_desc_container = nullptr;
1331 _entry_bci = InvocationEntryBci;
1332 _compile_id = compile_id;
1333 _comp_level = CompLevel_none;
1334 _compiler_type = type;
1335 _orig_pc_offset = 0;
1336 _num_stack_arg_slots = _method->constMethod()->num_stack_arg_slots();
1337
1338 if (offsets->value(CodeOffsets::Exceptions) != -1) {
1339 // Continuation enter intrinsic
1340 _exception_offset = code_offset() + offsets->value(CodeOffsets::Exceptions);
1341 } else {
1342 _exception_offset = 0;
1343 }
1344 // Native wrappers do not have deopt handlers. Make the values
1345 // something that will never match a pc like the nmethod vtable entry
1346 _deopt_handler_offset = 0;
1347 _deopt_mh_handler_offset = 0;
1348 _scc_entry = nullptr;
1349 _method_profiling_count = 0;
1350 _unwind_handler_offset = 0;
1351
1352 CHECKED_CAST(_metadata_offset, uint16_t, (align_up(code_buffer->total_oop_size(), oopSize)));
1353 int data_end_offset = _metadata_offset + align_up(code_buffer->total_metadata_size(), wordSize);
1354 #if INCLUDE_JVMCI
1355 // jvmci_data_size is 0 in native wrapper but we need to set offset
1356 // to correctly calculate metadata_end address
1357 CHECKED_CAST(_jvmci_data_offset, uint16_t, data_end_offset);
1358 #endif
1359 assert((data_offset() + data_end_offset) <= nmethod_size, "wrong nmethod's size: %d < %d", nmethod_size, (data_offset() + data_end_offset));
1360
1361 // native wrapper does not have read-only data but we need unique not null address
1362 _immutable_data = data_end();
1363 _immutable_data_size = 0;
1364 _nul_chk_table_offset = 0;
1365 _handler_table_offset = 0;
1366 _scopes_pcs_offset = 0;
1367 _scopes_data_offset = 0;
1368 #if INCLUDE_JVMCI
1369 _speculations_offset = 0;
1370 #endif
1371
1372 code_buffer->copy_code_and_locs_to(this);
1373 code_buffer->copy_values_to(this);
1374
1375 post_init();
1376 }
1377
1378 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
1379 ttyLocker ttyl; // keep the following output all in one block
1380 // This output goes directly to the tty, not the compiler log.
1381 // To enable tools to match it up with the compilation activity,
1382 // be sure to tag this tty output with the compile ID.
1383 if (xtty != nullptr) {
1384 xtty->begin_head("print_native_nmethod");
1385 xtty->method(_method);
1386 xtty->stamp();
1387 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
1388 }
1389 // Print the header part, then print the requested information.
1390 // This is both handled in decode2(), called via print_code() -> decode()
1391 if (PrintNativeNMethods) {
1392 tty->print_cr("-------------------------- Assembly (native nmethod) ---------------------------");
1393 print_code();
1394 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1395 #if defined(SUPPORT_DATA_STRUCTS)
1396 if (AbstractDisassembler::show_structs()) {
1397 if (oop_maps != nullptr) {
1398 tty->print("oop maps:"); // oop_maps->print_on(tty) outputs a cr() at the beginning
1399 oop_maps->print_on(tty);
1400 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1401 }
1402 }
1403 #endif
1404 } else {
1405 print(); // print the header part only.
1406 }
1407 #if defined(SUPPORT_DATA_STRUCTS)
1408 if (AbstractDisassembler::show_structs()) {
1409 if (PrintRelocations) {
1410 print_relocations_on(tty);
1411 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1412 }
1413 }
1414 #endif
1415 if (xtty != nullptr) {
1416 xtty->tail("print_native_nmethod");
1417 }
1418 }
1419 }
1420
1421 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
1422 return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
1423 }
1424
1425 void* nmethod::operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw () {
1426 // Try MethodNonProfiled and MethodProfiled.
1427 void* return_value = CodeCache::allocate(nmethod_size, CodeBlobType::MethodNonProfiled);
1428 if (return_value != nullptr || !allow_NonNMethod_space) return return_value;
1429 // Try NonNMethod or give up.
1430 return CodeCache::allocate(nmethod_size, CodeBlobType::NonNMethod);
1431 }
1432
1433 // For normal JIT compiled code
1434 nmethod::nmethod(
1435 Method* method,
1436 CompilerType type,
1437 int nmethod_size,
1438 int immutable_data_size,
1439 int compile_id,
1440 int entry_bci,
1441 address immutable_data,
1442 CodeOffsets* offsets,
1443 int orig_pc_offset,
1444 DebugInformationRecorder* debug_info,
1445 Dependencies* dependencies,
1446 CodeBuffer *code_buffer,
1447 int frame_size,
1448 OopMapSet* oop_maps,
1449 ExceptionHandlerTable* handler_table,
1450 ImplicitExceptionTable* nul_chk_table,
1451 AbstractCompiler* compiler,
1452 CompLevel comp_level
1453 , SCCEntry* scc_entry
1454 #if INCLUDE_JVMCI
1455 , char* speculations,
1456 int speculations_len,
1457 JVMCINMethodData* jvmci_data
1458 #endif
1459 )
1460 : CodeBlob("nmethod", CodeBlobKind::Nmethod, code_buffer, nmethod_size, sizeof(nmethod),
1461 offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps, false),
1462 _deoptimization_generation(0),
1463 _gc_epoch(CodeCache::gc_epoch()),
1464 _method(method),
1465 _osr_link(nullptr)
1466 {
1467 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
1468 {
1469 debug_only(NoSafepointVerifier nsv;)
1470 assert_locked_or_safepoint(CodeCache_lock);
1471
1472 init_defaults(code_buffer, offsets);
1473 _scc_entry = scc_entry;
1474 _method_profiling_count = 0;
1475
1476 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
1477 _entry_bci = entry_bci;
1478 _compile_id = compile_id;
1479 _comp_level = comp_level;
1480 _compiler_type = type;
1481 _orig_pc_offset = orig_pc_offset;
1482
1483 _num_stack_arg_slots = entry_bci != InvocationEntryBci ? 0 : _method->constMethod()->num_stack_arg_slots();
1484
1485 set_ctable_begin(header_begin() + content_offset());
1486
1487 #if INCLUDE_JVMCI
1488 if (compiler->is_jvmci()) {
1489 // JVMCI might not produce any stub sections
1490 if (offsets->value(CodeOffsets::Exceptions) != -1) {
1491 _exception_offset = code_offset() + offsets->value(CodeOffsets::Exceptions);
1492 } else {
1493 _exception_offset = -1;
1494 }
1495 if (offsets->value(CodeOffsets::Deopt) != -1) {
1496 _deopt_handler_offset = code_offset() + offsets->value(CodeOffsets::Deopt);
1497 } else {
1498 _deopt_handler_offset = -1;
1499 }
1500 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
1501 _deopt_mh_handler_offset = code_offset() + offsets->value(CodeOffsets::DeoptMH);
1502 } else {
1503 _deopt_mh_handler_offset = -1;
1504 }
1505 } else
1506 #endif
1507 {
1508 // Exception handler and deopt handler are in the stub section
1509 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
1510 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
1511
1512 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
1513 _deopt_handler_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
1514 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
1515 _deopt_mh_handler_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
1516 } else {
1517 _deopt_mh_handler_offset = -1;
1518 }
1519 }
1520 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
1521 // C1 generates UnwindHandler at the end of instructions section.
1522 // Calculate positive offset as distance between the start of stubs section
1523 // (which is also the end of instructions section) and the start of the handler.
1524 int unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
1525 CHECKED_CAST(_unwind_handler_offset, int16_t, (_stub_offset - unwind_handler_offset));
1526 } else {
1527 _unwind_handler_offset = -1;
1528 }
1529 CHECKED_CAST(_metadata_offset, uint16_t, (align_up(code_buffer->total_oop_size(), oopSize)));
1530 int metadata_end_offset = _metadata_offset + align_up(code_buffer->total_metadata_size(), wordSize);
1531
1532 #if INCLUDE_JVMCI
1533 CHECKED_CAST(_jvmci_data_offset, uint16_t, metadata_end_offset);
1534 int jvmci_data_size = compiler->is_jvmci() ? jvmci_data->size() : 0;
1535 DEBUG_ONLY( int data_end_offset = _jvmci_data_offset + align_up(jvmci_data_size, oopSize); )
1536 #else
1537 DEBUG_ONLY( int data_end_offset = metadata_end_offset; )
1538 #endif
1539 assert((data_offset() + data_end_offset) <= nmethod_size, "wrong nmethod's size: %d > %d",
1540 (data_offset() + data_end_offset), nmethod_size);
1541
1542 _immutable_data_size = immutable_data_size;
1543 if (immutable_data_size > 0) {
1544 assert(immutable_data != nullptr, "required");
1545 _immutable_data = immutable_data;
1546 } else {
1547 // We need unique not null address
1548 _immutable_data = data_end();
1549 }
1550 CHECKED_CAST(_nul_chk_table_offset, uint16_t, (align_up((int)dependencies->size_in_bytes(), oopSize)));
1551 CHECKED_CAST(_handler_table_offset, uint16_t, (_nul_chk_table_offset + align_up(nul_chk_table->size_in_bytes(), oopSize)));
1552 _scopes_pcs_offset = _handler_table_offset + align_up(handler_table->size_in_bytes(), oopSize);
1553 _scopes_data_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
1554
1555 #if INCLUDE_JVMCI
1556 _speculations_offset = _scopes_data_offset + align_up(debug_info->data_size(), oopSize);
1557 DEBUG_ONLY( int immutable_data_end_offset = _speculations_offset + align_up(speculations_len, oopSize); )
1558 #else
1559 DEBUG_ONLY( int immutable_data_end_offset = _scopes_data_offset + align_up(debug_info->data_size(), oopSize); )
1560 #endif
1561 assert(immutable_data_end_offset <= immutable_data_size, "wrong read-only data size: %d > %d",
1562 immutable_data_end_offset, immutable_data_size);
1563
1564 // Copy code and relocation info
1565 code_buffer->copy_code_and_locs_to(this);
1566 // Copy oops and metadata
1567 code_buffer->copy_values_to(this);
1568 dependencies->copy_to(this);
1569 // Copy PcDesc and ScopeDesc data
1570 debug_info->copy_to(this);
1571
1572 // Create cache after PcDesc data is copied - it will be used to initialize cache
1573 _pc_desc_container = new PcDescContainer(scopes_pcs_begin());
1574
1575 #if INCLUDE_JVMCI
1576 if (compiler->is_jvmci()) {
1577 // Initialize the JVMCINMethodData object inlined into nm
1578 jvmci_nmethod_data()->copy(jvmci_data);
1579 }
1580 #endif
1581
1582 // Copy contents of ExceptionHandlerTable to nmethod
1583 handler_table->copy_to(this);
1584 nul_chk_table->copy_to(this);
1585
1586 #if INCLUDE_JVMCI
1587 // Copy speculations to nmethod
1588 if (speculations_size() != 0) {
1589 memcpy(speculations_begin(), speculations, speculations_len);
1590 }
1591 #endif
1592
1593 post_init();
1594
1595 // we use the information of entry points to find out if a method is
1596 // static or non static
1597 assert(compiler->is_c2() || compiler->is_jvmci() ||
1598 _method->is_static() == (entry_point() == verified_entry_point()),
1599 " entry points must be same for static methods and vice versa");
1600 }
1601 }
1602
1603 // Print a short set of xml attributes to identify this nmethod. The
1604 // output should be embedded in some other element.
1605 void nmethod::log_identity(xmlStream* log) const {
1606 assert(log->inside_attrs_or_error(), "printing attributes");
1607 log->print(" code_compile_id='%d'", compile_id());
1608 const char* nm_kind = compile_kind();
1609 if (nm_kind != nullptr) log->print(" code_compile_kind='%s'", nm_kind);
1610 log->print(" code_compiler='%s'", compiler_name());
1611 if (TieredCompilation) {
1612 log->print(" code_compile_level='%d'", comp_level());
1613 }
1614 #if INCLUDE_JVMCI
1615 if (jvmci_nmethod_data() != nullptr) {
1616 const char* jvmci_name = jvmci_nmethod_data()->name();
1617 if (jvmci_name != nullptr) {
1618 log->print(" jvmci_mirror_name='");
1619 log->text("%s", jvmci_name);
1620 log->print("'");
1621 }
1622 }
1623 #endif
1624 }
1625
1626
1627 #define LOG_OFFSET(log, name) \
1628 if (p2i(name##_end()) - p2i(name##_begin())) \
1629 log->print(" " XSTR(name) "_offset='" INTX_FORMAT "'" , \
1630 p2i(name##_begin()) - p2i(this))
1631
1632
1633 void nmethod::log_new_nmethod() const {
1634 if (LogCompilation && xtty != nullptr) {
1635 ttyLocker ttyl;
1636 xtty->begin_elem("nmethod");
1637 log_identity(xtty);
1638 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
1639 xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
1640
1641 LOG_OFFSET(xtty, relocation);
1642 LOG_OFFSET(xtty, consts);
1643 LOG_OFFSET(xtty, insts);
1644 LOG_OFFSET(xtty, stub);
1645 LOG_OFFSET(xtty, scopes_data);
1646 LOG_OFFSET(xtty, scopes_pcs);
1647 LOG_OFFSET(xtty, dependencies);
1648 LOG_OFFSET(xtty, handler_table);
1649 LOG_OFFSET(xtty, nul_chk_table);
1650 LOG_OFFSET(xtty, oops);
1651 LOG_OFFSET(xtty, metadata);
1652
1653 xtty->method(method());
1654 xtty->stamp();
1655 xtty->end_elem();
1656 }
1657 }
1658
1659 #undef LOG_OFFSET
1660
1661
1662 // Print out more verbose output usually for a newly created nmethod.
1663 void nmethod::print_on(outputStream* st, const char* msg) const {
1664 if (st != nullptr) {
1665 ttyLocker ttyl;
1666 if (WizardMode) {
1667 CompileTask::print(st, this, msg, /*short_form:*/ true);
1668 st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
1669 } else {
1670 CompileTask::print(st, this, msg, /*short_form:*/ false);
1671 }
1672 }
1673 }
1674
1675 void nmethod::maybe_print_nmethod(const DirectiveSet* directive) {
1676 bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
1677 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
1678 print_nmethod(printnmethods);
1679 }
1680 }
1681
1682 void nmethod::print_nmethod(bool printmethod) {
1683 ttyLocker ttyl; // keep the following output all in one block
1684 if (xtty != nullptr) {
1685 xtty->begin_head("print_nmethod");
1686 log_identity(xtty);
1687 xtty->stamp();
1688 xtty->end_head();
1689 }
1690 // Print the header part, then print the requested information.
1691 // This is both handled in decode2().
1692 if (printmethod) {
1693 ResourceMark m;
1694 if (is_compiled_by_c1()) {
1695 tty->cr();
1696 tty->print_cr("============================= C1-compiled nmethod ==============================");
1697 }
1698 if (is_compiled_by_jvmci()) {
1699 tty->cr();
1700 tty->print_cr("=========================== JVMCI-compiled nmethod =============================");
1701 }
1702 tty->print_cr("----------------------------------- Assembly -----------------------------------");
1703 decode2(tty);
1704 #if defined(SUPPORT_DATA_STRUCTS)
1705 if (AbstractDisassembler::show_structs()) {
1706 // Print the oops from the underlying CodeBlob as well.
1707 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1708 print_oops(tty);
1709 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1710 print_metadata(tty);
1711 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1712 print_pcs_on(tty);
1713 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1714 if (oop_maps() != nullptr) {
1715 tty->print("oop maps:"); // oop_maps()->print_on(tty) outputs a cr() at the beginning
1716 oop_maps()->print_on(tty);
1717 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1718 }
1719 }
1720 #endif
1721 } else {
1722 print(); // print the header part only.
1723 }
1724
1725 #if defined(SUPPORT_DATA_STRUCTS)
1726 if (AbstractDisassembler::show_structs()) {
1727 methodHandle mh(Thread::current(), _method);
1728 if (printmethod || PrintDebugInfo || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDebugInfo)) {
1729 print_scopes();
1730 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1731 }
1732 if (printmethod || PrintRelocations || CompilerOracle::has_option(mh, CompileCommandEnum::PrintRelocations)) {
1733 print_relocations_on(tty);
1734 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1735 }
1736 if (printmethod || PrintDependencies || CompilerOracle::has_option(mh, CompileCommandEnum::PrintDependencies)) {
1737 print_dependencies_on(tty);
1738 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1739 }
1740 if (printmethod || PrintExceptionHandlers) {
1741 print_handler_table();
1742 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1743 print_nul_chk_table();
1744 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1745 }
1746
1747 if (printmethod) {
1748 print_recorded_oops();
1749 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1750 print_recorded_metadata();
1751 tty->print_cr("- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ");
1752 }
1753 }
1754 #endif
1755
1756 if (xtty != nullptr) {
1757 xtty->tail("print_nmethod");
1758 }
1759 }
1760
1761
1762 // Promote one word from an assembly-time handle to a live embedded oop.
1763 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1764 if (handle == nullptr ||
1765 // As a special case, IC oops are initialized to 1 or -1.
1766 handle == (jobject) Universe::non_oop_word()) {
1767 *(void**)dest = handle;
1768 } else {
1769 *dest = JNIHandles::resolve_non_null(handle);
1770 }
1771 }
1772
1773
1774 // Have to have the same name because it's called by a template
1775 void nmethod::copy_values(GrowableArray<jobject>* array) {
1776 int length = array->length();
1777 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1778 oop* dest = oops_begin();
1779 for (int index = 0 ; index < length; index++) {
1780 initialize_immediate_oop(&dest[index], array->at(index));
1781 }
1782
1783 // Now we can fix up all the oops in the code. We need to do this
1784 // in the code because the assembler uses jobjects as placeholders.
1785 // The code and relocations have already been initialized by the
1786 // CodeBlob constructor, so it is valid even at this early point to
1787 // iterate over relocations and patch the code.
1788 fix_oop_relocations(nullptr, nullptr, /*initialize_immediates=*/ true);
1789 }
1790
1791 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1792 int length = array->length();
1793 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1794 Metadata** dest = metadata_begin();
1795 for (int index = 0 ; index < length; index++) {
1796 dest[index] = array->at(index);
1797 }
1798 }
1799
1800 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1801 // re-patch all oop-bearing instructions, just in case some oops moved
1802 RelocIterator iter(this, begin, end);
1803 while (iter.next()) {
1804 if (iter.type() == relocInfo::oop_type) {
1805 oop_Relocation* reloc = iter.oop_reloc();
1806 if (initialize_immediates && reloc->oop_is_immediate()) {
1807 oop* dest = reloc->oop_addr();
1808 jobject obj = *reinterpret_cast<jobject*>(dest);
1809 initialize_immediate_oop(dest, obj);
1810 }
1811 // Refresh the oop-related bits of this instruction.
1812 reloc->fix_oop_relocation();
1813 } else if (iter.type() == relocInfo::metadata_type) {
1814 metadata_Relocation* reloc = iter.metadata_reloc();
1815 reloc->fix_metadata_relocation();
1816 }
1817 }
1818 }
1819
1820 static void install_post_call_nop_displacement(nmethod* nm, address pc) {
1821 NativePostCallNop* nop = nativePostCallNop_at((address) pc);
1822 intptr_t cbaddr = (intptr_t) nm;
1823 intptr_t offset = ((intptr_t) pc) - cbaddr;
1824
1825 int oopmap_slot = nm->oop_maps()->find_slot_for_offset(int((intptr_t) pc - (intptr_t) nm->code_begin()));
1826 if (oopmap_slot < 0) { // this can happen at asynchronous (non-safepoint) stackwalks
1827 log_debug(codecache)("failed to find oopmap for cb: " INTPTR_FORMAT " offset: %d", cbaddr, (int) offset);
1828 } else if (!nop->patch(oopmap_slot, offset)) {
1829 log_debug(codecache)("failed to encode %d %d", oopmap_slot, (int) offset);
1830 }
1831 }
1832
1833 void nmethod::finalize_relocations() {
1834 NoSafepointVerifier nsv;
1835
1836 GrowableArray<NativeMovConstReg*> virtual_call_data;
1837
1838 // Make sure that post call nops fill in nmethod offsets eagerly so
1839 // we don't have to race with deoptimization
1840 RelocIterator iter(this);
1841 while (iter.next()) {
1842 if (iter.type() == relocInfo::virtual_call_type) {
1843 virtual_call_Relocation* r = iter.virtual_call_reloc();
1844 NativeMovConstReg* value = nativeMovConstReg_at(r->cached_value());
1845 virtual_call_data.append(value);
1846 } else if (iter.type() == relocInfo::post_call_nop_type) {
1847 post_call_nop_Relocation* const reloc = iter.post_call_nop_reloc();
1848 address pc = reloc->addr();
1849 install_post_call_nop_displacement(this, pc);
1850 }
1851 }
1852
1853 if (virtual_call_data.length() > 0) {
1854 // We allocate a block of CompiledICData per nmethod so the GC can purge this faster.
1855 _compiled_ic_data = new CompiledICData[virtual_call_data.length()];
1856 CompiledICData* next_data = _compiled_ic_data;
1857
1858 for (NativeMovConstReg* value : virtual_call_data) {
1859 value->set_data((intptr_t)next_data);
1860 next_data++;
1861 }
1862 }
1863 }
1864
1865 void nmethod::make_deoptimized() {
1866 if (!Continuations::enabled()) {
1867 // Don't deopt this again.
1868 set_deoptimized_done();
1869 return;
1870 }
1871
1872 assert(method() == nullptr || can_be_deoptimized(), "");
1873
1874 CompiledICLocker ml(this);
1875 assert(CompiledICLocker::is_safe(this), "mt unsafe call");
1876
1877 // If post call nops have been already patched, we can just bail-out.
1878 if (has_been_deoptimized()) {
1879 return;
1880 }
1881
1882 ResourceMark rm;
1883 RelocIterator iter(this, oops_reloc_begin());
1884
1885 while (iter.next()) {
1886
1887 switch (iter.type()) {
1888 case relocInfo::virtual_call_type: {
1889 CompiledIC *ic = CompiledIC_at(&iter);
1890 address pc = ic->end_of_call();
1891 NativePostCallNop* nop = nativePostCallNop_at(pc);
1892 if (nop != nullptr) {
1893 nop->make_deopt();
1894 }
1895 assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
1896 break;
1897 }
1898 case relocInfo::static_call_type:
1899 case relocInfo::opt_virtual_call_type: {
1900 CompiledDirectCall *csc = CompiledDirectCall::at(iter.reloc());
1901 address pc = csc->end_of_call();
1902 NativePostCallNop* nop = nativePostCallNop_at(pc);
1903 //tty->print_cr(" - static pc %p", pc);
1904 if (nop != nullptr) {
1905 nop->make_deopt();
1906 }
1907 // We can't assert here, there are some calls to stubs / runtime
1908 // that have reloc data and doesn't have a post call NOP.
1909 //assert(NativeDeoptInstruction::is_deopt_at(pc), "check");
1910 break;
1911 }
1912 default:
1913 break;
1914 }
1915 }
1916 // Don't deopt this again.
1917 set_deoptimized_done();
1918 }
1919
1920 void nmethod::verify_clean_inline_caches() {
1921 assert(CompiledICLocker::is_safe(this), "mt unsafe call");
1922
1923 ResourceMark rm;
1924 RelocIterator iter(this, oops_reloc_begin());
1925 while(iter.next()) {
1926 switch(iter.type()) {
1927 case relocInfo::virtual_call_type: {
1928 CompiledIC *ic = CompiledIC_at(&iter);
1929 CodeBlob *cb = CodeCache::find_blob(ic->destination());
1930 assert(cb != nullptr, "destination not in CodeBlob?");
1931 nmethod* nm = cb->as_nmethod_or_null();
1932 if (nm != nullptr) {
1933 // Verify that inline caches pointing to bad nmethods are clean
1934 if (!nm->is_in_use() || nm->is_unloading()) {
1935 assert(ic->is_clean(), "IC should be clean");
1936 }
1937 }
1938 break;
1939 }
1940 case relocInfo::static_call_type:
1941 case relocInfo::opt_virtual_call_type: {
1942 CompiledDirectCall *cdc = CompiledDirectCall::at(iter.reloc());
1943 CodeBlob *cb = CodeCache::find_blob(cdc->destination());
1944 assert(cb != nullptr, "destination not in CodeBlob?");
1945 nmethod* nm = cb->as_nmethod_or_null();
1946 if (nm != nullptr) {
1947 // Verify that inline caches pointing to bad nmethods are clean
1948 if (!nm->is_in_use() || nm->is_unloading() || nm->method()->code() != nm) {
1949 assert(cdc->is_clean(), "IC should be clean");
1950 }
1951 }
1952 break;
1953 }
1954 default:
1955 break;
1956 }
1957 }
1958 }
1959
1960 void nmethod::mark_as_maybe_on_stack() {
1961 Atomic::store(&_gc_epoch, CodeCache::gc_epoch());
1962 }
1963
1964 bool nmethod::is_maybe_on_stack() {
1965 // If the condition below is true, it means that the nmethod was found to
1966 // be alive the previous completed marking cycle.
1967 return Atomic::load(&_gc_epoch) >= CodeCache::previous_completed_gc_marking_cycle();
1968 }
1969
1970 void nmethod::inc_decompile_count() {
1971 if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
1972 // Could be gated by ProfileTraps, but do not bother...
1973 Method* m = method();
1974 if (m == nullptr) return;
1975 MethodData* mdo = m->method_data();
1976 if (mdo == nullptr) return;
1977 // There is a benign race here. See comments in methodData.hpp.
1978 mdo->inc_decompile_count();
1979 }
1980
1981 void nmethod::inc_method_profiling_count() {
1982 Atomic::inc(&_method_profiling_count);
1983 }
1984
1985 uint64_t nmethod::method_profiling_count() {
1986 return _method_profiling_count;
1987 }
1988
1989 bool nmethod::try_transition(signed char new_state_int) {
1990 signed char new_state = new_state_int;
1991 assert_lock_strong(NMethodState_lock);
1992 signed char old_state = _state;
1993 if (old_state >= new_state) {
1994 // Ensure monotonicity of transitions.
1995 return false;
1996 }
1997 Atomic::store(&_state, new_state);
1998 return true;
1999 }
2000
2001 void nmethod::invalidate_osr_method() {
2002 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
2003 // Remove from list of active nmethods
2004 if (method() != nullptr) {
2005 method()->method_holder()->remove_osr_nmethod(this);
2006 }
2007 }
2008
2009 void nmethod::log_state_change() const {
2010 if (LogCompilation) {
2011 if (xtty != nullptr) {
2012 ttyLocker ttyl; // keep the following output all in one block
2013 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'",
2014 os::current_thread_id());
2015 log_identity(xtty);
2016 xtty->stamp();
2017 xtty->end_elem();
2018 }
2019 }
2020
2021 CompileTask::print_ul(this, "made not entrant");
2022 if (PrintCompilation) {
2023 print_on(tty, "made not entrant");
2024 }
2025 }
2026
2027 void nmethod::unlink_from_method() {
2028 if (method() != nullptr) {
2029 method()->unlink_code(this);
2030 }
2031 }
2032
2033 // Invalidate code
2034 bool nmethod::make_not_entrant(bool make_not_entrant) {
2035 // This can be called while the system is already at a safepoint which is ok
2036 NoSafepointVerifier nsv;
2037
2038 if (is_unloading()) {
2039 // If the nmethod is unloading, then it is already not entrant through
2040 // the nmethod entry barriers. No need to do anything; GC will unload it.
2041 return false;
2042 }
2043
2044 if (Atomic::load(&_state) == not_entrant) {
2045 // Avoid taking the lock if already in required state.
2046 // This is safe from races because the state is an end-state,
2047 // which the nmethod cannot back out of once entered.
2048 // No need for fencing either.
2049 return false;
2050 }
2051
2052 {
2053 // Enter critical section. Does not block for safepoint.
2054 ConditionalMutexLocker ml(NMethodState_lock, !NMethodState_lock->owned_by_self(), Mutex::_no_safepoint_check_flag);
2055
2056 if (Atomic::load(&_state) == not_entrant) {
2057 // another thread already performed this transition so nothing
2058 // to do, but return false to indicate this.
2059 return false;
2060 }
2061
2062 if (is_osr_method()) {
2063 // This logic is equivalent to the logic below for patching the
2064 // verified entry point of regular methods.
2065 // this effectively makes the osr nmethod not entrant
2066 invalidate_osr_method();
2067 } else {
2068 // The caller can be calling the method statically or through an inline
2069 // cache call.
2070 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
2071 SharedRuntime::get_handle_wrong_method_stub());
2072 }
2073
2074 if (update_recompile_counts()) {
2075 // Mark the method as decompiled.
2076 inc_decompile_count();
2077 }
2078
2079 BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2080 if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
2081 // If nmethod entry barriers are not supported, we won't mark
2082 // nmethods as on-stack when they become on-stack. So we
2083 // degrade to a less accurate flushing strategy, for now.
2084 mark_as_maybe_on_stack();
2085 }
2086
2087 // Change state
2088 bool success = try_transition(not_entrant);
2089 assert(success, "Transition can't fail");
2090
2091 // Log the transition once
2092 log_state_change();
2093
2094 // Remove nmethod from method.
2095 unlink_from_method();
2096
2097 if (make_not_entrant) {
2098 // Keep cached code if it was simply replaced
2099 // otherwise make it not entrant too.
2100 SCCache::invalidate(_scc_entry);
2101 }
2102
2103 CompileBroker::log_not_entrant(this);
2104 } // leave critical region under NMethodState_lock
2105
2106 #if INCLUDE_JVMCI
2107 // Invalidate can't occur while holding the Patching lock
2108 JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
2109 if (nmethod_data != nullptr) {
2110 nmethod_data->invalidate_nmethod_mirror(this);
2111 }
2112 #endif
2113
2114 #ifdef ASSERT
2115 if (is_osr_method() && method() != nullptr) {
2116 // Make sure osr nmethod is invalidated, i.e. not on the list
2117 bool found = method()->method_holder()->remove_osr_nmethod(this);
2118 assert(!found, "osr nmethod should have been invalidated");
2119 }
2120 #endif
2121
2122 return true;
2123 }
2124
2125 // For concurrent GCs, there must be a handshake between unlink and flush
2126 void nmethod::unlink() {
2127 if (is_unlinked()) {
2128 // Already unlinked.
2129 return;
2130 }
2131
2132 flush_dependencies();
2133
2134 // unlink_from_method will take the NMethodState_lock.
2135 // In this case we don't strictly need it when unlinking nmethods from
2136 // the Method, because it is only concurrently unlinked by
2137 // the entry barrier, which acquires the per nmethod lock.
2138 unlink_from_method();
2139
2140 if (is_osr_method()) {
2141 invalidate_osr_method();
2142 }
2143
2144 #if INCLUDE_JVMCI
2145 // Clear the link between this nmethod and a HotSpotNmethod mirror
2146 JVMCINMethodData* nmethod_data = jvmci_nmethod_data();
2147 if (nmethod_data != nullptr) {
2148 nmethod_data->invalidate_nmethod_mirror(this);
2149 }
2150 #endif
2151
2152 // Post before flushing as jmethodID is being used
2153 post_compiled_method_unload();
2154
2155 // Register for flushing when it is safe. For concurrent class unloading,
2156 // that would be after the unloading handshake, and for STW class unloading
2157 // that would be when getting back to the VM thread.
2158 ClassUnloadingContext::context()->register_unlinked_nmethod(this);
2159 }
2160
2161 void nmethod::purge(bool unregister_nmethod) {
2162
2163 MutexLocker ml(CodeCache_lock, Mutex::_no_safepoint_check_flag);
2164
2165 // completely deallocate this method
2166 Events::log_nmethod_flush(Thread::current(), "flushing %s nmethod " INTPTR_FORMAT, is_osr_method() ? "osr" : "", p2i(this));
2167 log_debug(codecache)("*flushing %s nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT
2168 "/Free CodeCache:" SIZE_FORMAT "Kb",
2169 is_osr_method() ? "osr" : "",_compile_id, p2i(this), CodeCache::blob_count(),
2170 CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024);
2171
2172 // We need to deallocate any ExceptionCache data.
2173 // Note that we do not need to grab the nmethod lock for this, it
2174 // better be thread safe if we're disposing of it!
2175 ExceptionCache* ec = exception_cache();
2176 while(ec != nullptr) {
2177 ExceptionCache* next = ec->next();
2178 delete ec;
2179 ec = next;
2180 }
2181 if (_pc_desc_container != nullptr) {
2182 delete _pc_desc_container;
2183 }
2184 delete[] _compiled_ic_data;
2185
2186 if (_immutable_data != data_end()) {
2187 os::free(_immutable_data);
2188 _immutable_data = data_end(); // Valid not null address
2189 }
2190 if (unregister_nmethod) {
2191 Universe::heap()->unregister_nmethod(this);
2192 }
2193 CodeCache::unregister_old_nmethod(this);
2194
2195 CodeBlob::purge();
2196 }
2197
2198 oop nmethod::oop_at(int index) const {
2199 if (index == 0) {
2200 return nullptr;
2201 }
2202 return NMethodAccess<AS_NO_KEEPALIVE>::oop_load(oop_addr_at(index));
2203 }
2204
2205 oop nmethod::oop_at_phantom(int index) const {
2206 if (index == 0) {
2207 return nullptr;
2208 }
2209 return NMethodAccess<ON_PHANTOM_OOP_REF>::oop_load(oop_addr_at(index));
2210 }
2211
2212 //
2213 // Notify all classes this nmethod is dependent on that it is no
2214 // longer dependent.
2215
2216 void nmethod::flush_dependencies() {
2217 if (!has_flushed_dependencies()) {
2218 set_has_flushed_dependencies(true);
2219 for (Dependencies::DepStream deps(this); deps.next(); ) {
2220 if (deps.type() == Dependencies::call_site_target_value) {
2221 // CallSite dependencies are managed on per-CallSite instance basis.
2222 oop call_site = deps.argument_oop(0);
2223 MethodHandles::clean_dependency_context(call_site);
2224 } else {
2225 InstanceKlass* ik = deps.context_type();
2226 if (ik == nullptr) {
2227 continue; // ignore things like evol_method
2228 }
2229 // During GC liveness of dependee determines class that needs to be updated.
2230 // The GC may clean dependency contexts concurrently and in parallel.
2231 ik->clean_dependency_context();
2232 }
2233 }
2234 }
2235 }
2236
2237 void nmethod::post_compiled_method(CompileTask* task) {
2238 task->mark_success();
2239 task->set_nm_content_size(content_size());
2240 task->set_nm_insts_size(insts_size());
2241 task->set_nm_total_size(total_size());
2242
2243 // task->is_scc() is true only for loaded cached code.
2244 // nmethod::_scc_entry is set for loaded and stored cached code
2245 // to invalidate the entry when nmethod is deoptimized.
2246 // There is option to not store in archive cached code.
2247 guarantee((_scc_entry != nullptr) || !task->is_scc() || VerifyCachedCode, "sanity");
2248
2249 // JVMTI -- compiled method notification (must be done outside lock)
2250 post_compiled_method_load_event();
2251
2252 if (CompilationLog::log() != nullptr) {
2253 CompilationLog::log()->log_nmethod(JavaThread::current(), this);
2254 }
2255
2256 const DirectiveSet* directive = task->directive();
2257 maybe_print_nmethod(directive);
2258 }
2259
2260 // ------------------------------------------------------------------
2261 // post_compiled_method_load_event
2262 // new method for install_code() path
2263 // Transfer information from compilation to jvmti
2264 void nmethod::post_compiled_method_load_event(JvmtiThreadState* state) {
2265 // This is a bad time for a safepoint. We don't want
2266 // this nmethod to get unloaded while we're queueing the event.
2267 NoSafepointVerifier nsv;
2268
2269 Method* m = method();
2270 HOTSPOT_COMPILED_METHOD_LOAD(
2271 (char *) m->klass_name()->bytes(),
2272 m->klass_name()->utf8_length(),
2273 (char *) m->name()->bytes(),
2274 m->name()->utf8_length(),
2275 (char *) m->signature()->bytes(),
2276 m->signature()->utf8_length(),
2277 insts_begin(), insts_size());
2278
2279
2280 if (JvmtiExport::should_post_compiled_method_load()) {
2281 // Only post unload events if load events are found.
2282 set_load_reported();
2283 // If a JavaThread hasn't been passed in, let the Service thread
2284 // (which is a real Java thread) post the event
2285 JvmtiDeferredEvent event = JvmtiDeferredEvent::compiled_method_load_event(this);
2286 if (state == nullptr) {
2287 // Execute any barrier code for this nmethod as if it's called, since
2288 // keeping it alive looks like stack walking.
2289 run_nmethod_entry_barrier();
2290 ServiceThread::enqueue_deferred_event(&event);
2291 } else {
2292 // This enters the nmethod barrier outside in the caller.
2293 state->enqueue_event(&event);
2294 }
2295 }
2296 }
2297
2298 void nmethod::post_compiled_method_unload() {
2299 assert(_method != nullptr, "just checking");
2300 DTRACE_METHOD_UNLOAD_PROBE(method());
2301
2302 // If a JVMTI agent has enabled the CompiledMethodUnload event then
2303 // post the event. The Method* will not be valid when this is freed.
2304
2305 // Don't bother posting the unload if the load event wasn't posted.
2306 if (load_reported() && JvmtiExport::should_post_compiled_method_unload()) {
2307 JvmtiDeferredEvent event =
2308 JvmtiDeferredEvent::compiled_method_unload_event(
2309 method()->jmethod_id(), insts_begin());
2310 ServiceThread::enqueue_deferred_event(&event);
2311 }
2312 }
2313
2314 // Iterate over metadata calling this function. Used by RedefineClasses
2315 void nmethod::metadata_do(MetadataClosure* f) {
2316 {
2317 // Visit all immediate references that are embedded in the instruction stream.
2318 RelocIterator iter(this, oops_reloc_begin());
2319 while (iter.next()) {
2320 if (iter.type() == relocInfo::metadata_type) {
2321 metadata_Relocation* r = iter.metadata_reloc();
2322 // In this metadata, we must only follow those metadatas directly embedded in
2323 // the code. Other metadatas (oop_index>0) are seen as part of
2324 // the metadata section below.
2325 assert(1 == (r->metadata_is_immediate()) +
2326 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
2327 "metadata must be found in exactly one place");
2328 if (r->metadata_is_immediate() && r->metadata_value() != nullptr) {
2329 Metadata* md = r->metadata_value();
2330 if (md != _method) f->do_metadata(md);
2331 }
2332 } else if (iter.type() == relocInfo::virtual_call_type) {
2333 // Check compiledIC holders associated with this nmethod
2334 ResourceMark rm;
2335 CompiledIC *ic = CompiledIC_at(&iter);
2336 ic->metadata_do(f);
2337 }
2338 }
2339 }
2340
2341 // Visit the metadata section
2342 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
2343 if (*p == Universe::non_oop_word() || *p == nullptr) continue; // skip non-oops
2344 Metadata* md = *p;
2345 f->do_metadata(md);
2346 }
2347
2348 // Visit metadata not embedded in the other places.
2349 if (_method != nullptr) f->do_metadata(_method);
2350 }
2351
2352 // Heuristic for nuking nmethods even though their oops are live.
2353 // Main purpose is to reduce code cache pressure and get rid of
2354 // nmethods that don't seem to be all that relevant any longer.
2355 bool nmethod::is_cold() {
2356 if (!MethodFlushing || is_native_method() || is_not_installed()) {
2357 // No heuristic unloading at all
2358 return false;
2359 }
2360
2361 if (!is_maybe_on_stack() && is_not_entrant()) {
2362 // Not entrant nmethods that are not on any stack can just
2363 // be removed
2364 return true;
2365 }
2366
2367 BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2368 if (bs_nm == nullptr || !bs_nm->supports_entry_barrier(this)) {
2369 // On platforms that don't support nmethod entry barriers, we can't
2370 // trust the temporal aspect of the gc epochs. So we can't detect
2371 // cold nmethods on such platforms.
2372 return false;
2373 }
2374
2375 if (!UseCodeCacheFlushing) {
2376 // Bail out if we don't heuristically remove nmethods
2377 return false;
2378 }
2379
2380 // Other code can be phased out more gradually after N GCs
2381 return CodeCache::previous_completed_gc_marking_cycle() > _gc_epoch + 2 * CodeCache::cold_gc_count();
2382 }
2383
2384 // The _is_unloading_state encodes a tuple comprising the unloading cycle
2385 // and the result of IsUnloadingBehaviour::is_unloading() for that cycle.
2386 // This is the bit layout of the _is_unloading_state byte: 00000CCU
2387 // CC refers to the cycle, which has 2 bits, and U refers to the result of
2388 // IsUnloadingBehaviour::is_unloading() for that unloading cycle.
2389
2390 class IsUnloadingState: public AllStatic {
2391 static const uint8_t _is_unloading_mask = 1;
2392 static const uint8_t _is_unloading_shift = 0;
2393 static const uint8_t _unloading_cycle_mask = 6;
2394 static const uint8_t _unloading_cycle_shift = 1;
2395
2396 static uint8_t set_is_unloading(uint8_t state, bool value) {
2397 state &= (uint8_t)~_is_unloading_mask;
2398 if (value) {
2399 state |= 1 << _is_unloading_shift;
2400 }
2401 assert(is_unloading(state) == value, "unexpected unloading cycle overflow");
2402 return state;
2403 }
2404
2405 static uint8_t set_unloading_cycle(uint8_t state, uint8_t value) {
2406 state &= (uint8_t)~_unloading_cycle_mask;
2407 state |= (uint8_t)(value << _unloading_cycle_shift);
2408 assert(unloading_cycle(state) == value, "unexpected unloading cycle overflow");
2409 return state;
2410 }
2411
2412 public:
2413 static bool is_unloading(uint8_t state) { return (state & _is_unloading_mask) >> _is_unloading_shift == 1; }
2414 static uint8_t unloading_cycle(uint8_t state) { return (state & _unloading_cycle_mask) >> _unloading_cycle_shift; }
2415
2416 static uint8_t create(bool is_unloading, uint8_t unloading_cycle) {
2417 uint8_t state = 0;
2418 state = set_is_unloading(state, is_unloading);
2419 state = set_unloading_cycle(state, unloading_cycle);
2420 return state;
2421 }
2422 };
2423
2424 bool nmethod::is_unloading() {
2425 uint8_t state = Atomic::load(&_is_unloading_state);
2426 bool state_is_unloading = IsUnloadingState::is_unloading(state);
2427 if (state_is_unloading) {
2428 return true;
2429 }
2430 uint8_t state_unloading_cycle = IsUnloadingState::unloading_cycle(state);
2431 uint8_t current_cycle = CodeCache::unloading_cycle();
2432 if (state_unloading_cycle == current_cycle) {
2433 return false;
2434 }
2435
2436 // The IsUnloadingBehaviour is responsible for calculating if the nmethod
2437 // should be unloaded. This can be either because there is a dead oop,
2438 // or because is_cold() heuristically determines it is time to unload.
2439 state_unloading_cycle = current_cycle;
2440 state_is_unloading = IsUnloadingBehaviour::is_unloading(this);
2441 uint8_t new_state = IsUnloadingState::create(state_is_unloading, state_unloading_cycle);
2442
2443 // Note that if an nmethod has dead oops, everyone will agree that the
2444 // nmethod is_unloading. However, the is_cold heuristics can yield
2445 // different outcomes, so we guard the computed result with a CAS
2446 // to ensure all threads have a shared view of whether an nmethod
2447 // is_unloading or not.
2448 uint8_t found_state = Atomic::cmpxchg(&_is_unloading_state, state, new_state, memory_order_relaxed);
2449
2450 if (found_state == state) {
2451 // First to change state, we win
2452 return state_is_unloading;
2453 } else {
2454 // State already set, so use it
2455 return IsUnloadingState::is_unloading(found_state);
2456 }
2457 }
2458
2459 void nmethod::clear_unloading_state() {
2460 uint8_t state = IsUnloadingState::create(false, CodeCache::unloading_cycle());
2461 Atomic::store(&_is_unloading_state, state);
2462 }
2463
2464
2465 // This is called at the end of the strong tracing/marking phase of a
2466 // GC to unload an nmethod if it contains otherwise unreachable
2467 // oops or is heuristically found to be not important.
2468 void nmethod::do_unloading(bool unloading_occurred) {
2469 // Make sure the oop's ready to receive visitors
2470 if (is_unloading()) {
2471 unlink();
2472 } else {
2473 unload_nmethod_caches(unloading_occurred);
2474 BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2475 if (bs_nm != nullptr) {
2476 bs_nm->disarm(this);
2477 }
2478 }
2479 }
2480
2481 void nmethod::oops_do(OopClosure* f, bool allow_dead) {
2482 // Prevent extra code cache walk for platforms that don't have immediate oops.
2483 if (relocInfo::mustIterateImmediateOopsInCode()) {
2484 RelocIterator iter(this, oops_reloc_begin());
2485
2486 while (iter.next()) {
2487 if (iter.type() == relocInfo::oop_type ) {
2488 oop_Relocation* r = iter.oop_reloc();
2489 // In this loop, we must only follow those oops directly embedded in
2490 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
2491 assert(1 == (r->oop_is_immediate()) +
2492 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
2493 "oop must be found in exactly one place");
2494 if (r->oop_is_immediate() && r->oop_value() != nullptr) {
2495 f->do_oop(r->oop_addr());
2496 }
2497 }
2498 }
2499 }
2500
2501 // Scopes
2502 // This includes oop constants not inlined in the code stream.
2503 for (oop* p = oops_begin(); p < oops_end(); p++) {
2504 if (*p == Universe::non_oop_word()) continue; // skip non-oops
2505 f->do_oop(p);
2506 }
2507 }
2508
2509 void nmethod::follow_nmethod(OopIterateClosure* cl) {
2510 // Process oops in the nmethod
2511 oops_do(cl);
2512
2513 // CodeCache unloading support
2514 mark_as_maybe_on_stack();
2515
2516 BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
2517 bs_nm->disarm(this);
2518
2519 // There's an assumption made that this function is not used by GCs that
2520 // relocate objects, and therefore we don't call fix_oop_relocations.
2521 }
2522
2523 nmethod* volatile nmethod::_oops_do_mark_nmethods;
2524
2525 void nmethod::oops_do_log_change(const char* state) {
2526 LogTarget(Trace, gc, nmethod) lt;
2527 if (lt.is_enabled()) {
2528 LogStream ls(lt);
2529 CompileTask::print(&ls, this, state, true /* short_form */);
2530 }
2531 }
2532
2533 bool nmethod::oops_do_try_claim() {
2534 if (oops_do_try_claim_weak_request()) {
2535 nmethod* result = oops_do_try_add_to_list_as_weak_done();
2536 assert(result == nullptr, "adding to global list as weak done must always succeed.");
2537 return true;
2538 }
2539 return false;
2540 }
2541
2542 bool nmethod::oops_do_try_claim_weak_request() {
2543 assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2544
2545 if ((_oops_do_mark_link == nullptr) &&
2546 (Atomic::replace_if_null(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag)))) {
2547 oops_do_log_change("oops_do, mark weak request");
2548 return true;
2549 }
2550 return false;
2551 }
2552
2553 void nmethod::oops_do_set_strong_done(nmethod* old_head) {
2554 _oops_do_mark_link = mark_link(old_head, claim_strong_done_tag);
2555 }
2556
2557 nmethod::oops_do_mark_link* nmethod::oops_do_try_claim_strong_done() {
2558 assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2559
2560 oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, mark_link(nullptr, claim_weak_request_tag), mark_link(this, claim_strong_done_tag));
2561 if (old_next == nullptr) {
2562 oops_do_log_change("oops_do, mark strong done");
2563 }
2564 return old_next;
2565 }
2566
2567 nmethod::oops_do_mark_link* nmethod::oops_do_try_add_strong_request(nmethod::oops_do_mark_link* next) {
2568 assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2569 assert(next == mark_link(this, claim_weak_request_tag), "Should be claimed as weak");
2570
2571 oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, next, mark_link(this, claim_strong_request_tag));
2572 if (old_next == next) {
2573 oops_do_log_change("oops_do, mark strong request");
2574 }
2575 return old_next;
2576 }
2577
2578 bool nmethod::oops_do_try_claim_weak_done_as_strong_done(nmethod::oops_do_mark_link* next) {
2579 assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2580 assert(extract_state(next) == claim_weak_done_tag, "Should be claimed as weak done");
2581
2582 oops_do_mark_link* old_next = Atomic::cmpxchg(&_oops_do_mark_link, next, mark_link(extract_nmethod(next), claim_strong_done_tag));
2583 if (old_next == next) {
2584 oops_do_log_change("oops_do, mark weak done -> mark strong done");
2585 return true;
2586 }
2587 return false;
2588 }
2589
2590 nmethod* nmethod::oops_do_try_add_to_list_as_weak_done() {
2591 assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2592
2593 assert(extract_state(_oops_do_mark_link) == claim_weak_request_tag ||
2594 extract_state(_oops_do_mark_link) == claim_strong_request_tag,
2595 "must be but is nmethod " PTR_FORMAT " %u", p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
2596
2597 nmethod* old_head = Atomic::xchg(&_oops_do_mark_nmethods, this);
2598 // Self-loop if needed.
2599 if (old_head == nullptr) {
2600 old_head = this;
2601 }
2602 // Try to install end of list and weak done tag.
2603 if (Atomic::cmpxchg(&_oops_do_mark_link, mark_link(this, claim_weak_request_tag), mark_link(old_head, claim_weak_done_tag)) == mark_link(this, claim_weak_request_tag)) {
2604 oops_do_log_change("oops_do, mark weak done");
2605 return nullptr;
2606 } else {
2607 return old_head;
2608 }
2609 }
2610
2611 void nmethod::oops_do_add_to_list_as_strong_done() {
2612 assert(SafepointSynchronize::is_at_safepoint(), "only at safepoint");
2613
2614 nmethod* old_head = Atomic::xchg(&_oops_do_mark_nmethods, this);
2615 // Self-loop if needed.
2616 if (old_head == nullptr) {
2617 old_head = this;
2618 }
2619 assert(_oops_do_mark_link == mark_link(this, claim_strong_done_tag), "must be but is nmethod " PTR_FORMAT " state %u",
2620 p2i(extract_nmethod(_oops_do_mark_link)), extract_state(_oops_do_mark_link));
2621
2622 oops_do_set_strong_done(old_head);
2623 }
2624
2625 void nmethod::oops_do_process_weak(OopsDoProcessor* p) {
2626 if (!oops_do_try_claim_weak_request()) {
2627 // Failed to claim for weak processing.
2628 oops_do_log_change("oops_do, mark weak request fail");
2629 return;
2630 }
2631
2632 p->do_regular_processing(this);
2633
2634 nmethod* old_head = oops_do_try_add_to_list_as_weak_done();
2635 if (old_head == nullptr) {
2636 return;
2637 }
2638 oops_do_log_change("oops_do, mark weak done fail");
2639 // Adding to global list failed, another thread added a strong request.
2640 assert(extract_state(_oops_do_mark_link) == claim_strong_request_tag,
2641 "must be but is %u", extract_state(_oops_do_mark_link));
2642
2643 oops_do_log_change("oops_do, mark weak request -> mark strong done");
2644
2645 oops_do_set_strong_done(old_head);
2646 // Do missing strong processing.
2647 p->do_remaining_strong_processing(this);
2648 }
2649
2650 void nmethod::oops_do_process_strong(OopsDoProcessor* p) {
2651 oops_do_mark_link* next_raw = oops_do_try_claim_strong_done();
2652 if (next_raw == nullptr) {
2653 p->do_regular_processing(this);
2654 oops_do_add_to_list_as_strong_done();
2655 return;
2656 }
2657 // Claim failed. Figure out why and handle it.
2658 if (oops_do_has_weak_request(next_raw)) {
2659 oops_do_mark_link* old = next_raw;
2660 // Claim failed because being weak processed (state == "weak request").
2661 // Try to request deferred strong processing.
2662 next_raw = oops_do_try_add_strong_request(old);
2663 if (next_raw == old) {
2664 // Successfully requested deferred strong processing.
2665 return;
2666 }
2667 // Failed because of a concurrent transition. No longer in "weak request" state.
2668 }
2669 if (oops_do_has_any_strong_state(next_raw)) {
2670 // Already claimed for strong processing or requested for such.
2671 return;
2672 }
2673 if (oops_do_try_claim_weak_done_as_strong_done(next_raw)) {
2674 // Successfully claimed "weak done" as "strong done". Do the missing marking.
2675 p->do_remaining_strong_processing(this);
2676 return;
2677 }
2678 // Claim failed, some other thread got it.
2679 }
2680
2681 void nmethod::oops_do_marking_prologue() {
2682 assert_at_safepoint();
2683
2684 log_trace(gc, nmethod)("oops_do_marking_prologue");
2685 assert(_oops_do_mark_nmethods == nullptr, "must be empty");
2686 }
2687
2688 void nmethod::oops_do_marking_epilogue() {
2689 assert_at_safepoint();
2690
2691 nmethod* next = _oops_do_mark_nmethods;
2692 _oops_do_mark_nmethods = nullptr;
2693 if (next != nullptr) {
2694 nmethod* cur;
2695 do {
2696 cur = next;
2697 next = extract_nmethod(cur->_oops_do_mark_link);
2698 cur->_oops_do_mark_link = nullptr;
2699 DEBUG_ONLY(cur->verify_oop_relocations());
2700
2701 LogTarget(Trace, gc, nmethod) lt;
2702 if (lt.is_enabled()) {
2703 LogStream ls(lt);
2704 CompileTask::print(&ls, cur, "oops_do, unmark", /*short_form:*/ true);
2705 }
2706 // End if self-loop has been detected.
2707 } while (cur != next);
2708 }
2709 log_trace(gc, nmethod)("oops_do_marking_epilogue");
2710 }
2711
2712 inline bool includes(void* p, void* from, void* to) {
2713 return from <= p && p < to;
2714 }
2715
2716
2717 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2718 assert(count >= 2, "must be sentinel values, at least");
2719
2720 #ifdef ASSERT
2721 // must be sorted and unique; we do a binary search in find_pc_desc()
2722 int prev_offset = pcs[0].pc_offset();
2723 assert(prev_offset == PcDesc::lower_offset_limit,
2724 "must start with a sentinel");
2725 for (int i = 1; i < count; i++) {
2726 int this_offset = pcs[i].pc_offset();
2727 assert(this_offset > prev_offset, "offsets must be sorted");
2728 prev_offset = this_offset;
2729 }
2730 assert(prev_offset == PcDesc::upper_offset_limit,
2731 "must end with a sentinel");
2732 #endif //ASSERT
2733
2734 // Search for MethodHandle invokes and tag the nmethod.
2735 for (int i = 0; i < count; i++) {
2736 if (pcs[i].is_method_handle_invoke()) {
2737 set_has_method_handle_invokes(true);
2738 break;
2739 }
2740 }
2741 assert(has_method_handle_invokes() == (_deopt_mh_handler_offset != -1), "must have deopt mh handler");
2742
2743 int size = count * sizeof(PcDesc);
2744 assert(scopes_pcs_size() >= size, "oob");
2745 memcpy(scopes_pcs_begin(), pcs, size);
2746
2747 // Adjust the final sentinel downward.
2748 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2749 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2750 last_pc->set_pc_offset(content_size() + 1);
2751 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2752 // Fill any rounding gaps with copies of the last record.
2753 last_pc[1] = last_pc[0];
2754 }
2755 // The following assert could fail if sizeof(PcDesc) is not
2756 // an integral multiple of oopSize (the rounding term).
2757 // If it fails, change the logic to always allocate a multiple
2758 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2759 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2760 }
2761
2762 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2763 assert(scopes_data_size() >= size, "oob");
2764 memcpy(scopes_data_begin(), buffer, size);
2765 }
2766
2767 #ifdef ASSERT
2768 static PcDesc* linear_search(int pc_offset, bool approximate, PcDesc* lower, PcDesc* upper) {
2769 PcDesc* res = nullptr;
2770 assert(lower != nullptr && lower->pc_offset() == PcDesc::lower_offset_limit,
2771 "must start with a sentinel");
2772 // lower + 1 to exclude initial sentinel
2773 for (PcDesc* p = lower + 1; p < upper; p++) {
2774 NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2775 if (match_desc(p, pc_offset, approximate)) {
2776 if (res == nullptr) {
2777 res = p;
2778 } else {
2779 res = (PcDesc*) badAddress;
2780 }
2781 }
2782 }
2783 return res;
2784 }
2785 #endif
2786
2787
2788 #ifndef PRODUCT
2789 // Version of method to collect statistic
2790 PcDesc* PcDescContainer::find_pc_desc(address pc, bool approximate, address code_begin,
2791 PcDesc* lower, PcDesc* upper) {
2792 ++pc_nmethod_stats.pc_desc_queries;
2793 if (approximate) ++pc_nmethod_stats.pc_desc_approx;
2794
2795 PcDesc* desc = _pc_desc_cache.last_pc_desc();
2796 assert(desc != nullptr, "PcDesc cache should be initialized already");
2797 if (desc->pc_offset() == (pc - code_begin)) {
2798 // Cached value matched
2799 ++pc_nmethod_stats.pc_desc_tests;
2800 ++pc_nmethod_stats.pc_desc_repeats;
2801 return desc;
2802 }
2803 return find_pc_desc_internal(pc, approximate, code_begin, lower, upper);
2804 }
2805 #endif
2806
2807 // Finds a PcDesc with real-pc equal to "pc"
2808 PcDesc* PcDescContainer::find_pc_desc_internal(address pc, bool approximate, address code_begin,
2809 PcDesc* lower_incl, PcDesc* upper_incl) {
2810 if ((pc < code_begin) ||
2811 (pc - code_begin) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2812 return nullptr; // PC is wildly out of range
2813 }
2814 int pc_offset = (int) (pc - code_begin);
2815
2816 // Check the PcDesc cache if it contains the desired PcDesc
2817 // (This as an almost 100% hit rate.)
2818 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2819 if (res != nullptr) {
2820 assert(res == linear_search(pc_offset, approximate, lower_incl, upper_incl), "cache ok");
2821 return res;
2822 }
2823
2824 // Fallback algorithm: quasi-linear search for the PcDesc
2825 // Find the last pc_offset less than the given offset.
2826 // The successor must be the required match, if there is a match at all.
2827 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2828 PcDesc* lower = lower_incl; // this is initial sentinel
2829 PcDesc* upper = upper_incl - 1; // exclude final sentinel
2830 if (lower >= upper) return nullptr; // no PcDescs at all
2831
2832 #define assert_LU_OK \
2833 /* invariant on lower..upper during the following search: */ \
2834 assert(lower->pc_offset() < pc_offset, "sanity"); \
2835 assert(upper->pc_offset() >= pc_offset, "sanity")
2836 assert_LU_OK;
2837
2838 // Use the last successful return as a split point.
2839 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2840 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2841 if (mid->pc_offset() < pc_offset) {
2842 lower = mid;
2843 } else {
2844 upper = mid;
2845 }
2846
2847 // Take giant steps at first (4096, then 256, then 16, then 1)
2848 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2849 const int RADIX = (1 << LOG2_RADIX);
2850 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2851 while ((mid = lower + step) < upper) {
2852 assert_LU_OK;
2853 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2854 if (mid->pc_offset() < pc_offset) {
2855 lower = mid;
2856 } else {
2857 upper = mid;
2858 break;
2859 }
2860 }
2861 assert_LU_OK;
2862 }
2863
2864 // Sneak up on the value with a linear search of length ~16.
2865 while (true) {
2866 assert_LU_OK;
2867 mid = lower + 1;
2868 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2869 if (mid->pc_offset() < pc_offset) {
2870 lower = mid;
2871 } else {
2872 upper = mid;
2873 break;
2874 }
2875 }
2876 #undef assert_LU_OK
2877
2878 if (match_desc(upper, pc_offset, approximate)) {
2879 assert(upper == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
2880 if (!Thread::current_in_asgct()) {
2881 // we don't want to modify the cache if we're in ASGCT
2882 // which is typically called in a signal handler
2883 _pc_desc_cache.add_pc_desc(upper);
2884 }
2885 return upper;
2886 } else {
2887 assert(nullptr == linear_search(pc_offset, approximate, lower_incl, upper_incl), "search mismatch");
2888 return nullptr;
2889 }
2890 }
2891
2892 bool nmethod::check_dependency_on(DepChange& changes) {
2893 // What has happened:
2894 // 1) a new class dependee has been added
2895 // 2) dependee and all its super classes have been marked
2896 bool found_check = false; // set true if we are upset
2897 for (Dependencies::DepStream deps(this); deps.next(); ) {
2898 // Evaluate only relevant dependencies.
2899 if (deps.spot_check_dependency_at(changes) != nullptr) {
2900 found_check = true;
2901 NOT_DEBUG(break);
2902 }
2903 }
2904 return found_check;
2905 }
2906
2907 // Called from mark_for_deoptimization, when dependee is invalidated.
2908 bool nmethod::is_dependent_on_method(Method* dependee) {
2909 for (Dependencies::DepStream deps(this); deps.next(); ) {
2910 if (deps.type() != Dependencies::evol_method)
2911 continue;
2912 Method* method = deps.method_argument(0);
2913 if (method == dependee) return true;
2914 }
2915 return false;
2916 }
2917
2918 void nmethod_init() {
2919 // make sure you didn't forget to adjust the filler fields
2920 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2921 }
2922
2923 // -----------------------------------------------------------------------------
2924 // Verification
2925
2926 class VerifyOopsClosure: public OopClosure {
2927 nmethod* _nm;
2928 bool _ok;
2929 public:
2930 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2931 bool ok() { return _ok; }
2932 virtual void do_oop(oop* p) {
2933 if (oopDesc::is_oop_or_null(*p)) return;
2934 // Print diagnostic information before calling print_nmethod().
2935 // Assertions therein might prevent call from returning.
2936 tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2937 p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2938 if (_ok) {
2939 _nm->print_nmethod(true);
2940 _ok = false;
2941 }
2942 }
2943 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2944 };
2945
2946 class VerifyMetadataClosure: public MetadataClosure {
2947 public:
2948 void do_metadata(Metadata* md) {
2949 if (md->is_method()) {
2950 Method* method = (Method*)md;
2951 assert(!method->is_old(), "Should not be installing old methods");
2952 }
2953 }
2954 };
2955
2956
2957 void nmethod::verify() {
2958 if (is_not_entrant())
2959 return;
2960
2961 // Make sure all the entry points are correctly aligned for patching.
2962 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2963
2964 // assert(oopDesc::is_oop(method()), "must be valid");
2965
2966 ResourceMark rm;
2967
2968 if (!CodeCache::contains(this)) {
2969 fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
2970 }
2971
2972 if(is_native_method() )
2973 return;
2974
2975 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2976 if (nm != this) {
2977 fatal("find_nmethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
2978 }
2979
2980 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2981 if (! p->verify(this)) {
2982 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
2983 }
2984 }
2985
2986 #ifdef ASSERT
2987 #if INCLUDE_JVMCI
2988 {
2989 // Verify that implicit exceptions that deoptimize have a PcDesc and OopMap
2990 ImmutableOopMapSet* oms = oop_maps();
2991 ImplicitExceptionTable implicit_table(this);
2992 for (uint i = 0; i < implicit_table.len(); i++) {
2993 int exec_offset = (int) implicit_table.get_exec_offset(i);
2994 if (implicit_table.get_exec_offset(i) == implicit_table.get_cont_offset(i)) {
2995 assert(pc_desc_at(code_begin() + exec_offset) != nullptr, "missing PcDesc");
2996 bool found = false;
2997 for (int i = 0, imax = oms->count(); i < imax; i++) {
2998 if (oms->pair_at(i)->pc_offset() == exec_offset) {
2999 found = true;
3000 break;
3001 }
3002 }
3003 assert(found, "missing oopmap");
3004 }
3005 }
3006 }
3007 #endif
3008 #endif
3009
3010 VerifyOopsClosure voc(this);
3011 oops_do(&voc);
3012 assert(voc.ok(), "embedded oops must be OK");
3013 Universe::heap()->verify_nmethod(this);
3014
3015 assert(_oops_do_mark_link == nullptr, "_oops_do_mark_link for %s should be nullptr but is " PTR_FORMAT,
3016 nm->method()->external_name(), p2i(_oops_do_mark_link));
3017 verify_scopes();
3018
3019 CompiledICLocker nm_verify(this);
3020 VerifyMetadataClosure vmc;
3021 metadata_do(&vmc);
3022 }
3023
3024
3025 void nmethod::verify_interrupt_point(address call_site, bool is_inline_cache) {
3026
3027 // Verify IC only when nmethod installation is finished.
3028 if (!is_not_installed()) {
3029 if (CompiledICLocker::is_safe(this)) {
3030 if (is_inline_cache) {
3031 CompiledIC_at(this, call_site);
3032 } else {
3033 CompiledDirectCall::at(call_site);
3034 }
3035 } else {
3036 CompiledICLocker ml_verify(this);
3037 if (is_inline_cache) {
3038 CompiledIC_at(this, call_site);
3039 } else {
3040 CompiledDirectCall::at(call_site);
3041 }
3042 }
3043 }
3044
3045 HandleMark hm(Thread::current());
3046
3047 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
3048 assert(pd != nullptr, "PcDesc must exist");
3049 for (ScopeDesc* sd = new ScopeDesc(this, pd);
3050 !sd->is_top(); sd = sd->sender()) {
3051 sd->verify();
3052 }
3053 }
3054
3055 void nmethod::verify_scopes() {
3056 if( !method() ) return; // Runtime stubs have no scope
3057 if (method()->is_native()) return; // Ignore stub methods.
3058 // iterate through all interrupt point
3059 // and verify the debug information is valid.
3060 RelocIterator iter(this);
3061 while (iter.next()) {
3062 address stub = nullptr;
3063 switch (iter.type()) {
3064 case relocInfo::virtual_call_type:
3065 verify_interrupt_point(iter.addr(), true /* is_inline_cache */);
3066 break;
3067 case relocInfo::opt_virtual_call_type:
3068 stub = iter.opt_virtual_call_reloc()->static_stub();
3069 verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
3070 break;
3071 case relocInfo::static_call_type:
3072 stub = iter.static_call_reloc()->static_stub();
3073 verify_interrupt_point(iter.addr(), false /* is_inline_cache */);
3074 break;
3075 case relocInfo::runtime_call_type:
3076 case relocInfo::runtime_call_w_cp_type: {
3077 address destination = iter.reloc()->value();
3078 // Right now there is no way to find out which entries support
3079 // an interrupt point. It would be nice if we had this
3080 // information in a table.
3081 break;
3082 }
3083 default:
3084 break;
3085 }
3086 assert(stub == nullptr || stub_contains(stub), "static call stub outside stub section");
3087 }
3088 }
3089
3090
3091 // -----------------------------------------------------------------------------
3092 // Printing operations
3093
3094 void nmethod::print() const {
3095 ttyLocker ttyl; // keep the following output all in one block
3096 print(tty);
3097 }
3098
3099 void nmethod::print(outputStream* st) const {
3100 ResourceMark rm;
3101
3102 st->print("Compiled method ");
3103
3104 if (is_compiled_by_c1()) {
3105 st->print("(c1) ");
3106 } else if (is_compiled_by_c2()) {
3107 st->print("(c2) ");
3108 } else if (is_compiled_by_jvmci()) {
3109 st->print("(JVMCI) ");
3110 } else {
3111 st->print("(n/a) ");
3112 }
3113
3114 print_on(st, nullptr);
3115
3116 if (WizardMode) {
3117 st->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
3118 st->print(" for method " INTPTR_FORMAT , p2i(method()));
3119 st->print(" { ");
3120 st->print_cr("%s ", state());
3121 st->print_cr("}:");
3122 }
3123 if (size () > 0) st->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3124 p2i(this),
3125 p2i(this) + size(),
3126 size());
3127 if (relocation_size () > 0) st->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3128 p2i(relocation_begin()),
3129 p2i(relocation_end()),
3130 relocation_size());
3131 if (consts_size () > 0) st->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3132 p2i(consts_begin()),
3133 p2i(consts_end()),
3134 consts_size());
3135 if (insts_size () > 0) st->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3136 p2i(insts_begin()),
3137 p2i(insts_end()),
3138 insts_size());
3139 if (stub_size () > 0) st->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3140 p2i(stub_begin()),
3141 p2i(stub_end()),
3142 stub_size());
3143 if (oops_size () > 0) st->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3144 p2i(oops_begin()),
3145 p2i(oops_end()),
3146 oops_size());
3147 if (metadata_size () > 0) st->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3148 p2i(metadata_begin()),
3149 p2i(metadata_end()),
3150 metadata_size());
3151 #if INCLUDE_JVMCI
3152 if (jvmci_data_size () > 0) st->print_cr(" JVMCI data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3153 p2i(jvmci_data_begin()),
3154 p2i(jvmci_data_end()),
3155 jvmci_data_size());
3156 #endif
3157 if (immutable_data_size() > 0) st->print_cr(" immutable data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3158 p2i(immutable_data_begin()),
3159 p2i(immutable_data_end()),
3160 immutable_data_size());
3161 if (dependencies_size () > 0) st->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3162 p2i(dependencies_begin()),
3163 p2i(dependencies_end()),
3164 dependencies_size());
3165 if (nul_chk_table_size() > 0) st->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3166 p2i(nul_chk_table_begin()),
3167 p2i(nul_chk_table_end()),
3168 nul_chk_table_size());
3169 if (handler_table_size() > 0) st->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3170 p2i(handler_table_begin()),
3171 p2i(handler_table_end()),
3172 handler_table_size());
3173 if (scopes_pcs_size () > 0) st->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3174 p2i(scopes_pcs_begin()),
3175 p2i(scopes_pcs_end()),
3176 scopes_pcs_size());
3177 if (scopes_data_size () > 0) st->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3178 p2i(scopes_data_begin()),
3179 p2i(scopes_data_end()),
3180 scopes_data_size());
3181 #if INCLUDE_JVMCI
3182 if (speculations_size () > 0) st->print_cr(" speculations [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
3183 p2i(speculations_begin()),
3184 p2i(speculations_end()),
3185 speculations_size());
3186 #endif
3187 if (SCCache::is_on() && _scc_entry != nullptr) {
3188 _scc_entry->print(st);
3189 }
3190 }
3191
3192 void nmethod::print_code() {
3193 ResourceMark m;
3194 ttyLocker ttyl;
3195 // Call the specialized decode method of this class.
3196 decode(tty);
3197 }
3198
3199 #ifndef PRODUCT // called InstanceKlass methods are available only then. Declared as PRODUCT_RETURN
3200
3201 void nmethod::print_dependencies_on(outputStream* out) {
3202 ResourceMark rm;
3203 stringStream st;
3204 st.print_cr("Dependencies:");
3205 for (Dependencies::DepStream deps(this); deps.next(); ) {
3206 deps.print_dependency(&st);
3207 InstanceKlass* ctxk = deps.context_type();
3208 if (ctxk != nullptr) {
3209 if (ctxk->is_dependent_nmethod(this)) {
3210 st.print_cr(" [nmethod<=klass]%s", ctxk->external_name());
3211 }
3212 }
3213 deps.log_dependency(); // put it into the xml log also
3214 }
3215 out->print_raw(st.as_string());
3216 }
3217 #endif
3218
3219 #if defined(SUPPORT_DATA_STRUCTS)
3220
3221 // Print the oops from the underlying CodeBlob.
3222 void nmethod::print_oops(outputStream* st) {
3223 ResourceMark m;
3224 st->print("Oops:");
3225 if (oops_begin() < oops_end()) {
3226 st->cr();
3227 for (oop* p = oops_begin(); p < oops_end(); p++) {
3228 Disassembler::print_location((unsigned char*)p, (unsigned char*)oops_begin(), (unsigned char*)oops_end(), st, true, false);
3229 st->print(PTR_FORMAT " ", *((uintptr_t*)p));
3230 if (Universe::contains_non_oop_word(p)) {
3231 st->print_cr("NON_OOP");
3232 continue; // skip non-oops
3233 }
3234 if (*p == nullptr) {
3235 st->print_cr("nullptr-oop");
3236 continue; // skip non-oops
3237 }
3238 (*p)->print_value_on(st);
3239 st->cr();
3240 }
3241 } else {
3242 st->print_cr(" <list empty>");
3243 }
3244 }
3245
3246 // Print metadata pool.
3247 void nmethod::print_metadata(outputStream* st) {
3248 ResourceMark m;
3249 st->print("Metadata:");
3250 if (metadata_begin() < metadata_end()) {
3251 st->cr();
3252 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
3253 Disassembler::print_location((unsigned char*)p, (unsigned char*)metadata_begin(), (unsigned char*)metadata_end(), st, true, false);
3254 st->print(PTR_FORMAT " ", *((uintptr_t*)p));
3255 if (*p && *p != Universe::non_oop_word()) {
3256 (*p)->print_value_on(st);
3257 }
3258 st->cr();
3259 }
3260 } else {
3261 st->print_cr(" <list empty>");
3262 }
3263 }
3264
3265 #ifndef PRODUCT // ScopeDesc::print_on() is available only then. Declared as PRODUCT_RETURN
3266 void nmethod::print_scopes_on(outputStream* st) {
3267 // Find the first pc desc for all scopes in the code and print it.
3268 ResourceMark rm;
3269 st->print("scopes:");
3270 if (scopes_pcs_begin() < scopes_pcs_end()) {
3271 st->cr();
3272 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3273 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
3274 continue;
3275
3276 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
3277 while (sd != nullptr) {
3278 sd->print_on(st, p); // print output ends with a newline
3279 sd = sd->sender();
3280 }
3281 }
3282 } else {
3283 st->print_cr(" <list empty>");
3284 }
3285 }
3286 #endif
3287
3288 #ifndef PRODUCT // RelocIterator does support printing only then.
3289 void nmethod::print_relocations_on(outputStream* st) {
3290 ResourceMark m; // in case methods get printed via the debugger
3291 st->print_cr("relocations:");
3292 RelocIterator iter(this);
3293 iter.print_on(st);
3294 }
3295 #endif
3296
3297 void nmethod::print_pcs_on(outputStream* st) {
3298 ResourceMark m; // in case methods get printed via debugger
3299 st->print("pc-bytecode offsets:");
3300 if (scopes_pcs_begin() < scopes_pcs_end()) {
3301 st->cr();
3302 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3303 p->print_on(st, this); // print output ends with a newline
3304 }
3305 } else {
3306 st->print_cr(" <list empty>");
3307 }
3308 }
3309
3310 void nmethod::print_handler_table() {
3311 ExceptionHandlerTable(this).print(code_begin());
3312 }
3313
3314 void nmethod::print_nul_chk_table() {
3315 ImplicitExceptionTable(this).print(code_begin());
3316 }
3317
3318 void nmethod::print_recorded_oop(int log_n, int i) {
3319 void* value;
3320
3321 if (i == 0) {
3322 value = nullptr;
3323 } else {
3324 // Be careful around non-oop words. Don't create an oop
3325 // with that value, or it will assert in verification code.
3326 if (Universe::contains_non_oop_word(oop_addr_at(i))) {
3327 value = Universe::non_oop_word();
3328 } else {
3329 value = oop_at(i);
3330 }
3331 }
3332
3333 tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(value));
3334
3335 if (value == Universe::non_oop_word()) {
3336 tty->print("non-oop word");
3337 } else {
3338 if (value == 0) {
3339 tty->print("nullptr-oop");
3340 } else {
3341 oop_at(i)->print_value_on(tty);
3342 }
3343 }
3344
3345 tty->cr();
3346 }
3347
3348 void nmethod::print_recorded_oops() {
3349 const int n = oops_count();
3350 const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
3351 tty->print("Recorded oops:");
3352 if (n > 0) {
3353 tty->cr();
3354 for (int i = 0; i < n; i++) {
3355 print_recorded_oop(log_n, i);
3356 }
3357 } else {
3358 tty->print_cr(" <list empty>");
3359 }
3360 }
3361
3362 void nmethod::print_recorded_metadata() {
3363 const int n = metadata_count();
3364 const int log_n = (n<10) ? 1 : (n<100) ? 2 : (n<1000) ? 3 : (n<10000) ? 4 : 6;
3365 tty->print("Recorded metadata:");
3366 if (n > 0) {
3367 tty->cr();
3368 for (int i = 0; i < n; i++) {
3369 Metadata* m = metadata_at(i);
3370 tty->print("#%*d: " INTPTR_FORMAT " ", log_n, i, p2i(m));
3371 if (m == (Metadata*)Universe::non_oop_word()) {
3372 tty->print("non-metadata word");
3373 } else if (m == nullptr) {
3374 tty->print("nullptr-oop");
3375 } else {
3376 Metadata::print_value_on_maybe_null(tty, m);
3377 }
3378 tty->cr();
3379 }
3380 } else {
3381 tty->print_cr(" <list empty>");
3382 }
3383 }
3384 #endif
3385
3386 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
3387
3388 void nmethod::print_constant_pool(outputStream* st) {
3389 //-----------------------------------
3390 //---< Print the constant pool >---
3391 //-----------------------------------
3392 int consts_size = this->consts_size();
3393 if ( consts_size > 0 ) {
3394 unsigned char* cstart = this->consts_begin();
3395 unsigned char* cp = cstart;
3396 unsigned char* cend = cp + consts_size;
3397 unsigned int bytes_per_line = 4;
3398 unsigned int CP_alignment = 8;
3399 unsigned int n;
3400
3401 st->cr();
3402
3403 //---< print CP header to make clear what's printed >---
3404 if( ((uintptr_t)cp&(CP_alignment-1)) == 0 ) {
3405 n = bytes_per_line;
3406 st->print_cr("[Constant Pool]");
3407 Disassembler::print_location(cp, cstart, cend, st, true, true);
3408 Disassembler::print_hexdata(cp, n, st, true);
3409 st->cr();
3410 } else {
3411 n = (int)((uintptr_t)cp & (bytes_per_line-1));
3412 st->print_cr("[Constant Pool (unaligned)]");
3413 }
3414
3415 //---< print CP contents, bytes_per_line at a time >---
3416 while (cp < cend) {
3417 Disassembler::print_location(cp, cstart, cend, st, true, false);
3418 Disassembler::print_hexdata(cp, n, st, false);
3419 cp += n;
3420 n = bytes_per_line;
3421 st->cr();
3422 }
3423
3424 //---< Show potential alignment gap between constant pool and code >---
3425 cend = code_begin();
3426 if( cp < cend ) {
3427 n = 4;
3428 st->print_cr("[Code entry alignment]");
3429 while (cp < cend) {
3430 Disassembler::print_location(cp, cstart, cend, st, false, false);
3431 cp += n;
3432 st->cr();
3433 }
3434 }
3435 } else {
3436 st->print_cr("[Constant Pool (empty)]");
3437 }
3438 st->cr();
3439 }
3440
3441 #endif
3442
3443 // Disassemble this nmethod.
3444 // Print additional debug information, if requested. This could be code
3445 // comments, block comments, profiling counters, etc.
3446 // The undisassembled format is useful no disassembler library is available.
3447 // The resulting hex dump (with markers) can be disassembled later, or on
3448 // another system, when/where a disassembler library is available.
3449 void nmethod::decode2(outputStream* ost) const {
3450
3451 // Called from frame::back_trace_with_decode without ResourceMark.
3452 ResourceMark rm;
3453
3454 // Make sure we have a valid stream to print on.
3455 outputStream* st = ost ? ost : tty;
3456
3457 #if defined(SUPPORT_ABSTRACT_ASSEMBLY) && ! defined(SUPPORT_ASSEMBLY)
3458 const bool use_compressed_format = true;
3459 const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
3460 AbstractDisassembler::show_block_comment());
3461 #else
3462 const bool use_compressed_format = Disassembler::is_abstract();
3463 const bool compressed_with_comments = use_compressed_format && (AbstractDisassembler::show_comment() ||
3464 AbstractDisassembler::show_block_comment());
3465 #endif
3466
3467 st->cr();
3468 this->print(st);
3469 st->cr();
3470
3471 #if defined(SUPPORT_ASSEMBLY)
3472 //----------------------------------
3473 //---< Print real disassembly >---
3474 //----------------------------------
3475 if (! use_compressed_format) {
3476 st->print_cr("[Disassembly]");
3477 Disassembler::decode(const_cast<nmethod*>(this), st);
3478 st->bol();
3479 st->print_cr("[/Disassembly]");
3480 return;
3481 }
3482 #endif
3483
3484 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3485
3486 // Compressed undisassembled disassembly format.
3487 // The following status values are defined/supported:
3488 // = 0 - currently at bol() position, nothing printed yet on current line.
3489 // = 1 - currently at position after print_location().
3490 // > 1 - in the midst of printing instruction stream bytes.
3491 int compressed_format_idx = 0;
3492 int code_comment_column = 0;
3493 const int instr_maxlen = Assembler::instr_maxlen();
3494 const uint tabspacing = 8;
3495 unsigned char* start = this->code_begin();
3496 unsigned char* p = this->code_begin();
3497 unsigned char* end = this->code_end();
3498 unsigned char* pss = p; // start of a code section (used for offsets)
3499
3500 if ((start == nullptr) || (end == nullptr)) {
3501 st->print_cr("PrintAssembly not possible due to uninitialized section pointers");
3502 return;
3503 }
3504 #endif
3505
3506 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3507 //---< plain abstract disassembly, no comments or anything, just section headers >---
3508 if (use_compressed_format && ! compressed_with_comments) {
3509 const_cast<nmethod*>(this)->print_constant_pool(st);
3510
3511 //---< Open the output (Marker for post-mortem disassembler) >---
3512 st->print_cr("[MachCode]");
3513 const char* header = nullptr;
3514 address p0 = p;
3515 while (p < end) {
3516 address pp = p;
3517 while ((p < end) && (header == nullptr)) {
3518 header = nmethod_section_label(p);
3519 pp = p;
3520 p += Assembler::instr_len(p);
3521 }
3522 if (pp > p0) {
3523 AbstractDisassembler::decode_range_abstract(p0, pp, start, end, st, Assembler::instr_maxlen());
3524 p0 = pp;
3525 p = pp;
3526 header = nullptr;
3527 } else if (header != nullptr) {
3528 st->bol();
3529 st->print_cr("%s", header);
3530 header = nullptr;
3531 }
3532 }
3533 //---< Close the output (Marker for post-mortem disassembler) >---
3534 st->bol();
3535 st->print_cr("[/MachCode]");
3536 return;
3537 }
3538 #endif
3539
3540 #if defined(SUPPORT_ABSTRACT_ASSEMBLY)
3541 //---< abstract disassembly with comments and section headers merged in >---
3542 if (compressed_with_comments) {
3543 const_cast<nmethod*>(this)->print_constant_pool(st);
3544
3545 //---< Open the output (Marker for post-mortem disassembler) >---
3546 st->print_cr("[MachCode]");
3547 while ((p < end) && (p != nullptr)) {
3548 const int instruction_size_in_bytes = Assembler::instr_len(p);
3549
3550 //---< Block comments for nmethod. Interrupts instruction stream, if any. >---
3551 // Outputs a bol() before and a cr() after, but only if a comment is printed.
3552 // Prints nmethod_section_label as well.
3553 if (AbstractDisassembler::show_block_comment()) {
3554 print_block_comment(st, p);
3555 if (st->position() == 0) {
3556 compressed_format_idx = 0;
3557 }
3558 }
3559
3560 //---< New location information after line break >---
3561 if (compressed_format_idx == 0) {
3562 code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
3563 compressed_format_idx = 1;
3564 }
3565
3566 //---< Code comment for current instruction. Address range [p..(p+len)) >---
3567 unsigned char* p_end = p + (ssize_t)instruction_size_in_bytes;
3568 S390_ONLY(if (p_end > end) p_end = end;) // avoid getting past the end
3569
3570 if (AbstractDisassembler::show_comment() && const_cast<nmethod*>(this)->has_code_comment(p, p_end)) {
3571 //---< interrupt instruction byte stream for code comment >---
3572 if (compressed_format_idx > 1) {
3573 st->cr(); // interrupt byte stream
3574 st->cr(); // add an empty line
3575 code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
3576 }
3577 const_cast<nmethod*>(this)->print_code_comment_on(st, code_comment_column, p, p_end );
3578 st->bol();
3579 compressed_format_idx = 0;
3580 }
3581
3582 //---< New location information after line break >---
3583 if (compressed_format_idx == 0) {
3584 code_comment_column = Disassembler::print_location(p, pss, end, st, false, false);
3585 compressed_format_idx = 1;
3586 }
3587
3588 //---< Nicely align instructions for readability >---
3589 if (compressed_format_idx > 1) {
3590 Disassembler::print_delimiter(st);
3591 }
3592
3593 //---< Now, finally, print the actual instruction bytes >---
3594 unsigned char* p0 = p;
3595 p = Disassembler::decode_instruction_abstract(p, st, instruction_size_in_bytes, instr_maxlen);
3596 compressed_format_idx += (int)(p - p0);
3597
3598 if (Disassembler::start_newline(compressed_format_idx-1)) {
3599 st->cr();
3600 compressed_format_idx = 0;
3601 }
3602 }
3603 //---< Close the output (Marker for post-mortem disassembler) >---
3604 st->bol();
3605 st->print_cr("[/MachCode]");
3606 return;
3607 }
3608 #endif
3609 }
3610
3611 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
3612
3613 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
3614 RelocIterator iter(this, begin, end);
3615 bool have_one = false;
3616 while (iter.next()) {
3617 have_one = true;
3618 switch (iter.type()) {
3619 case relocInfo::none: return "no_reloc";
3620 case relocInfo::oop_type: {
3621 // Get a non-resizable resource-allocated stringStream.
3622 // Our callees make use of (nested) ResourceMarks.
3623 stringStream st(NEW_RESOURCE_ARRAY(char, 1024), 1024);
3624 oop_Relocation* r = iter.oop_reloc();
3625 oop obj = r->oop_value();
3626 st.print("oop(");
3627 if (obj == nullptr) st.print("nullptr");
3628 else obj->print_value_on(&st);
3629 st.print(")");
3630 return st.as_string();
3631 }
3632 case relocInfo::metadata_type: {
3633 stringStream st;
3634 metadata_Relocation* r = iter.metadata_reloc();
3635 Metadata* obj = r->metadata_value();
3636 st.print("metadata(");
3637 if (obj == nullptr) st.print("nullptr");
3638 else obj->print_value_on(&st);
3639 st.print(")");
3640 return st.as_string();
3641 }
3642 case relocInfo::runtime_call_type:
3643 case relocInfo::runtime_call_w_cp_type: {
3644 stringStream st;
3645 st.print("runtime_call");
3646 CallRelocation* r = (CallRelocation*)iter.reloc();
3647 address dest = r->destination();
3648 if (StubRoutines::contains(dest)) {
3649 StubCodeDesc* desc = StubCodeDesc::desc_for(dest);
3650 if (desc == nullptr) {
3651 desc = StubCodeDesc::desc_for(dest + frame::pc_return_offset);
3652 }
3653 if (desc != nullptr) {
3654 st.print(" Stub::%s", desc->name());
3655 return st.as_string();
3656 }
3657 }
3658 CodeBlob* cb = CodeCache::find_blob(dest);
3659 if (cb != nullptr) {
3660 st.print(" %s", cb->name());
3661 } else {
3662 ResourceMark rm;
3663 const int buflen = 1024;
3664 char* buf = NEW_RESOURCE_ARRAY(char, buflen);
3665 int offset;
3666 if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
3667 st.print(" %s", buf);
3668 if (offset != 0) {
3669 st.print("+%d", offset);
3670 }
3671 }
3672 }
3673 return st.as_string();
3674 }
3675 case relocInfo::virtual_call_type: {
3676 stringStream st;
3677 st.print_raw("virtual_call");
3678 virtual_call_Relocation* r = iter.virtual_call_reloc();
3679 Method* m = r->method_value();
3680 if (m != nullptr) {
3681 assert(m->is_method(), "");
3682 m->print_short_name(&st);
3683 }
3684 return st.as_string();
3685 }
3686 case relocInfo::opt_virtual_call_type: {
3687 stringStream st;
3688 st.print_raw("optimized virtual_call");
3689 opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
3690 Method* m = r->method_value();
3691 if (m != nullptr) {
3692 assert(m->is_method(), "");
3693 m->print_short_name(&st);
3694 }
3695 return st.as_string();
3696 }
3697 case relocInfo::static_call_type: {
3698 stringStream st;
3699 st.print_raw("static_call");
3700 static_call_Relocation* r = iter.static_call_reloc();
3701 Method* m = r->method_value();
3702 if (m != nullptr) {
3703 assert(m->is_method(), "");
3704 m->print_short_name(&st);
3705 }
3706 return st.as_string();
3707 }
3708 case relocInfo::static_stub_type: return "static_stub";
3709 case relocInfo::external_word_type: return "external_word";
3710 case relocInfo::internal_word_type: return "internal_word";
3711 case relocInfo::section_word_type: return "section_word";
3712 case relocInfo::poll_type: return "poll";
3713 case relocInfo::poll_return_type: return "poll_return";
3714 case relocInfo::trampoline_stub_type: return "trampoline_stub";
3715 case relocInfo::type_mask: return "type_bit_mask";
3716
3717 default:
3718 break;
3719 }
3720 }
3721 return have_one ? "other" : nullptr;
3722 }
3723
3724 // Return the last scope in (begin..end]
3725 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
3726 PcDesc* p = pc_desc_near(begin+1);
3727 if (p != nullptr && p->real_pc(this) <= end) {
3728 return new ScopeDesc(this, p);
3729 }
3730 return nullptr;
3731 }
3732
3733 const char* nmethod::nmethod_section_label(address pos) const {
3734 const char* label = nullptr;
3735 if (pos == code_begin()) label = "[Instructions begin]";
3736 if (pos == entry_point()) label = "[Entry Point]";
3737 if (pos == verified_entry_point()) label = "[Verified Entry Point]";
3738 if (has_method_handle_invokes() && (pos == deopt_mh_handler_begin())) label = "[Deopt MH Handler Code]";
3739 if (pos == consts_begin() && pos != insts_begin()) label = "[Constants]";
3740 // Check stub_code before checking exception_handler or deopt_handler.
3741 if (pos == this->stub_begin()) label = "[Stub Code]";
3742 if (JVMCI_ONLY(_exception_offset >= 0 &&) pos == exception_begin()) label = "[Exception Handler]";
3743 if (JVMCI_ONLY(_deopt_handler_offset != -1 &&) pos == deopt_handler_begin()) label = "[Deopt Handler Code]";
3744 return label;
3745 }
3746
3747 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels) const {
3748 if (print_section_labels) {
3749 const char* label = nmethod_section_label(block_begin);
3750 if (label != nullptr) {
3751 stream->bol();
3752 stream->print_cr("%s", label);
3753 }
3754 }
3755
3756 if (block_begin == entry_point()) {
3757 Method* m = method();
3758 if (m != nullptr) {
3759 stream->print(" # ");
3760 m->print_value_on(stream);
3761 stream->cr();
3762 }
3763 if (m != nullptr && !is_osr_method()) {
3764 ResourceMark rm;
3765 int sizeargs = m->size_of_parameters();
3766 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
3767 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
3768 {
3769 int sig_index = 0;
3770 if (!m->is_static())
3771 sig_bt[sig_index++] = T_OBJECT; // 'this'
3772 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
3773 BasicType t = ss.type();
3774 sig_bt[sig_index++] = t;
3775 if (type2size[t] == 2) {
3776 sig_bt[sig_index++] = T_VOID;
3777 } else {
3778 assert(type2size[t] == 1, "size is 1 or 2");
3779 }
3780 }
3781 assert(sig_index == sizeargs, "");
3782 }
3783 const char* spname = "sp"; // make arch-specific?
3784 SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs);
3785 int stack_slot_offset = this->frame_size() * wordSize;
3786 int tab1 = 14, tab2 = 24;
3787 int sig_index = 0;
3788 int arg_index = (m->is_static() ? 0 : -1);
3789 bool did_old_sp = false;
3790 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
3791 bool at_this = (arg_index == -1);
3792 bool at_old_sp = false;
3793 BasicType t = (at_this ? T_OBJECT : ss.type());
3794 assert(t == sig_bt[sig_index], "sigs in sync");
3795 if (at_this)
3796 stream->print(" # this: ");
3797 else
3798 stream->print(" # parm%d: ", arg_index);
3799 stream->move_to(tab1);
3800 VMReg fst = regs[sig_index].first();
3801 VMReg snd = regs[sig_index].second();
3802 if (fst->is_reg()) {
3803 stream->print("%s", fst->name());
3804 if (snd->is_valid()) {
3805 stream->print(":%s", snd->name());
3806 }
3807 } else if (fst->is_stack()) {
3808 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
3809 if (offset == stack_slot_offset) at_old_sp = true;
3810 stream->print("[%s+0x%x]", spname, offset);
3811 } else {
3812 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
3813 }
3814 stream->print(" ");
3815 stream->move_to(tab2);
3816 stream->print("= ");
3817 if (at_this) {
3818 m->method_holder()->print_value_on(stream);
3819 } else {
3820 bool did_name = false;
3821 if (!at_this && ss.is_reference()) {
3822 Symbol* name = ss.as_symbol();
3823 name->print_value_on(stream);
3824 did_name = true;
3825 }
3826 if (!did_name)
3827 stream->print("%s", type2name(t));
3828 }
3829 if (at_old_sp) {
3830 stream->print(" (%s of caller)", spname);
3831 did_old_sp = true;
3832 }
3833 stream->cr();
3834 sig_index += type2size[t];
3835 arg_index += 1;
3836 if (!at_this) ss.next();
3837 }
3838 if (!did_old_sp) {
3839 stream->print(" # ");
3840 stream->move_to(tab1);
3841 stream->print("[%s+0x%x]", spname, stack_slot_offset);
3842 stream->print(" (%s of caller)", spname);
3843 stream->cr();
3844 }
3845 }
3846 }
3847 }
3848
3849 // Returns whether this nmethod has code comments.
3850 bool nmethod::has_code_comment(address begin, address end) {
3851 // scopes?
3852 ScopeDesc* sd = scope_desc_in(begin, end);
3853 if (sd != nullptr) return true;
3854
3855 // relocations?
3856 const char* str = reloc_string_for(begin, end);
3857 if (str != nullptr) return true;
3858
3859 // implicit exceptions?
3860 int cont_offset = ImplicitExceptionTable(this).continuation_offset((uint)(begin - code_begin()));
3861 if (cont_offset != 0) return true;
3862
3863 return false;
3864 }
3865
3866 void nmethod::print_code_comment_on(outputStream* st, int column, address begin, address end) {
3867 ImplicitExceptionTable implicit_table(this);
3868 int pc_offset = (int)(begin - code_begin());
3869 int cont_offset = implicit_table.continuation_offset(pc_offset);
3870 bool oop_map_required = false;
3871 if (cont_offset != 0) {
3872 st->move_to(column, 6, 0);
3873 if (pc_offset == cont_offset) {
3874 st->print("; implicit exception: deoptimizes");
3875 oop_map_required = true;
3876 } else {
3877 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
3878 }
3879 }
3880
3881 // Find an oopmap in (begin, end]. We use the odd half-closed
3882 // interval so that oop maps and scope descs which are tied to the
3883 // byte after a call are printed with the call itself. OopMaps
3884 // associated with implicit exceptions are printed with the implicit
3885 // instruction.
3886 address base = code_begin();
3887 ImmutableOopMapSet* oms = oop_maps();
3888 if (oms != nullptr) {
3889 for (int i = 0, imax = oms->count(); i < imax; i++) {
3890 const ImmutableOopMapPair* pair = oms->pair_at(i);
3891 const ImmutableOopMap* om = pair->get_from(oms);
3892 address pc = base + pair->pc_offset();
3893 if (pc >= begin) {
3894 #if INCLUDE_JVMCI
3895 bool is_implicit_deopt = implicit_table.continuation_offset(pair->pc_offset()) == (uint) pair->pc_offset();
3896 #else
3897 bool is_implicit_deopt = false;
3898 #endif
3899 if (is_implicit_deopt ? pc == begin : pc > begin && pc <= end) {
3900 st->move_to(column, 6, 0);
3901 st->print("; ");
3902 om->print_on(st);
3903 oop_map_required = false;
3904 }
3905 }
3906 if (pc > end) {
3907 break;
3908 }
3909 }
3910 }
3911 assert(!oop_map_required, "missed oopmap");
3912
3913 Thread* thread = Thread::current();
3914
3915 // Print any debug info present at this pc.
3916 ScopeDesc* sd = scope_desc_in(begin, end);
3917 if (sd != nullptr) {
3918 st->move_to(column, 6, 0);
3919 if (sd->bci() == SynchronizationEntryBCI) {
3920 st->print(";*synchronization entry");
3921 } else if (sd->bci() == AfterBci) {
3922 st->print(";* method exit (unlocked if synchronized)");
3923 } else if (sd->bci() == UnwindBci) {
3924 st->print(";* unwind (locked if synchronized)");
3925 } else if (sd->bci() == AfterExceptionBci) {
3926 st->print(";* unwind (unlocked if synchronized)");
3927 } else if (sd->bci() == UnknownBci) {
3928 st->print(";* unknown");
3929 } else if (sd->bci() == InvalidFrameStateBci) {
3930 st->print(";* invalid frame state");
3931 } else {
3932 if (sd->method() == nullptr) {
3933 st->print("method is nullptr");
3934 } else if (sd->method()->is_native()) {
3935 st->print("method is native");
3936 } else {
3937 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
3938 st->print(";*%s", Bytecodes::name(bc));
3939 switch (bc) {
3940 case Bytecodes::_invokevirtual:
3941 case Bytecodes::_invokespecial:
3942 case Bytecodes::_invokestatic:
3943 case Bytecodes::_invokeinterface:
3944 {
3945 Bytecode_invoke invoke(methodHandle(thread, sd->method()), sd->bci());
3946 st->print(" ");
3947 if (invoke.name() != nullptr)
3948 invoke.name()->print_symbol_on(st);
3949 else
3950 st->print("<UNKNOWN>");
3951 break;
3952 }
3953 case Bytecodes::_getfield:
3954 case Bytecodes::_putfield:
3955 case Bytecodes::_getstatic:
3956 case Bytecodes::_putstatic:
3957 {
3958 Bytecode_field field(methodHandle(thread, sd->method()), sd->bci());
3959 st->print(" ");
3960 if (field.name() != nullptr)
3961 field.name()->print_symbol_on(st);
3962 else
3963 st->print("<UNKNOWN>");
3964 }
3965 default:
3966 break;
3967 }
3968 }
3969 st->print(" {reexecute=%d rethrow=%d return_oop=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop());
3970 }
3971
3972 // Print all scopes
3973 for (;sd != nullptr; sd = sd->sender()) {
3974 st->move_to(column, 6, 0);
3975 st->print("; -");
3976 if (sd->should_reexecute()) {
3977 st->print(" (reexecute)");
3978 }
3979 if (sd->method() == nullptr) {
3980 st->print("method is nullptr");
3981 } else {
3982 sd->method()->print_short_name(st);
3983 }
3984 int lineno = sd->method()->line_number_from_bci(sd->bci());
3985 if (lineno != -1) {
3986 st->print("@%d (line %d)", sd->bci(), lineno);
3987 } else {
3988 st->print("@%d", sd->bci());
3989 }
3990 st->cr();
3991 }
3992 }
3993
3994 // Print relocation information
3995 // Prevent memory leak: allocating without ResourceMark.
3996 ResourceMark rm;
3997 const char* str = reloc_string_for(begin, end);
3998 if (str != nullptr) {
3999 if (sd != nullptr) st->cr();
4000 st->move_to(column, 6, 0);
4001 st->print("; {%s}", str);
4002 }
4003 }
4004
4005 #endif
4006
4007 address nmethod::call_instruction_address(address pc) const {
4008 if (NativeCall::is_call_before(pc)) {
4009 NativeCall *ncall = nativeCall_before(pc);
4010 return ncall->instruction_address();
4011 }
4012 return nullptr;
4013 }
4014
4015 #if defined(SUPPORT_DATA_STRUCTS)
4016 void nmethod::print_value_on(outputStream* st) const {
4017 st->print("nmethod");
4018 print_on(st, nullptr);
4019 }
4020 #endif
4021
4022 #ifndef PRODUCT
4023
4024 void nmethod::print_calls(outputStream* st) {
4025 RelocIterator iter(this);
4026 while (iter.next()) {
4027 switch (iter.type()) {
4028 case relocInfo::virtual_call_type: {
4029 CompiledICLocker ml_verify(this);
4030 CompiledIC_at(&iter)->print();
4031 break;
4032 }
4033 case relocInfo::static_call_type:
4034 case relocInfo::opt_virtual_call_type:
4035 st->print_cr("Direct call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
4036 CompiledDirectCall::at(iter.reloc())->print();
4037 break;
4038 default:
4039 break;
4040 }
4041 }
4042 }
4043
4044 void nmethod::print_statistics() {
4045 ttyLocker ttyl;
4046 if (xtty != nullptr) xtty->head("statistics type='nmethod'");
4047 native_nmethod_stats.print_native_nmethod_stats();
4048 #ifdef COMPILER1
4049 c1_java_nmethod_stats.print_nmethod_stats("C1");
4050 #endif
4051 #ifdef COMPILER2
4052 c2_java_nmethod_stats.print_nmethod_stats("C2");
4053 #endif
4054 #if INCLUDE_JVMCI
4055 jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
4056 #endif
4057 unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
4058 DebugInformationRecorder::print_statistics();
4059 #ifndef PRODUCT
4060 pc_nmethod_stats.print_pc_stats();
4061 #endif
4062 Dependencies::print_statistics();
4063 if (xtty != nullptr) xtty->tail("statistics");
4064 }
4065
4066 #endif // !PRODUCT
4067
4068 #if INCLUDE_JVMCI
4069 void nmethod::update_speculation(JavaThread* thread) {
4070 jlong speculation = thread->pending_failed_speculation();
4071 if (speculation != 0) {
4072 guarantee(jvmci_nmethod_data() != nullptr, "failed speculation in nmethod without failed speculation list");
4073 jvmci_nmethod_data()->add_failed_speculation(this, speculation);
4074 thread->set_pending_failed_speculation(0);
4075 }
4076 }
4077
4078 const char* nmethod::jvmci_name() {
4079 if (jvmci_nmethod_data() != nullptr) {
4080 return jvmci_nmethod_data()->name();
4081 }
4082 return nullptr;
4083 }
4084 #endif