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