1 /*
2 * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "code/codeCache.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/dependencies.hpp"
29 #include "code/nativeInst.hpp"
30 #include "code/nmethod.hpp"
31 #include "code/scopeDesc.hpp"
32 #include "compiler/abstractCompiler.hpp"
33 #include "compiler/compileBroker.hpp"
34 #include "compiler/compileLog.hpp"
35 #include "compiler/compilerDirectives.hpp"
36 #include "compiler/directivesParser.hpp"
37 #include "compiler/disassembler.hpp"
38 #include "interpreter/bytecode.hpp"
39 #include "oops/methodData.hpp"
40 #include "oops/oop.inline.hpp"
41 #include "prims/jvmtiRedefineClassesTrace.hpp"
42 #include "prims/jvmtiImpl.hpp"
43 #include "runtime/atomic.inline.hpp"
44 #include "runtime/orderAccess.inline.hpp"
45 #include "runtime/os.hpp"
46 #include "runtime/sharedRuntime.hpp"
47 #include "runtime/sweeper.hpp"
48 #include "utilities/resourceHash.hpp"
49 #include "utilities/dtrace.hpp"
50 #include "utilities/events.hpp"
51 #include "utilities/xmlstream.hpp"
52 #include "logging/log.hpp"
53 #ifdef TARGET_ARCH_x86
54 # include "nativeInst_x86.hpp"
55 #endif
56 #ifdef TARGET_ARCH_sparc
57 # include "nativeInst_sparc.hpp"
58 #endif
59 #ifdef TARGET_ARCH_zero
60 # include "nativeInst_zero.hpp"
61 #endif
62 #ifdef TARGET_ARCH_arm
63 # include "nativeInst_arm.hpp"
64 #endif
65 #ifdef TARGET_ARCH_ppc
66 # include "nativeInst_ppc.hpp"
67 #endif
68 #ifdef SHARK
69 #include "shark/sharkCompiler.hpp"
70 #endif
71 #if INCLUDE_JVMCI
72 #include "jvmci/jvmciJavaClasses.hpp"
73 #endif
74
75 unsigned char nmethod::_global_unloading_clock = 0;
76
77 #ifdef DTRACE_ENABLED
78
79 // Only bother with this argument setup if dtrace is available
80
81 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
82 { \
83 Method* m = (method); \
84 if (m != NULL) { \
85 Symbol* klass_name = m->klass_name(); \
86 Symbol* name = m->name(); \
87 Symbol* signature = m->signature(); \
88 HOTSPOT_COMPILED_METHOD_UNLOAD( \
89 (char *) klass_name->bytes(), klass_name->utf8_length(), \
90 (char *) name->bytes(), name->utf8_length(), \
91 (char *) signature->bytes(), signature->utf8_length()); \
92 } \
93 }
94
95 #else // ndef DTRACE_ENABLED
96
97 #define DTRACE_METHOD_UNLOAD_PROBE(method)
98
99 #endif
100
101 bool nmethod::is_compiled_by_c1() const {
102 if (compiler() == NULL) {
103 return false;
104 }
105 return compiler()->is_c1();
106 }
107 bool nmethod::is_compiled_by_jvmci() const {
108 if (compiler() == NULL || method() == NULL) return false; // can happen during debug printing
109 if (is_native_method()) return false;
110 return compiler()->is_jvmci();
111 }
112 bool nmethod::is_compiled_by_c2() const {
113 if (compiler() == NULL) {
114 return false;
115 }
116 return compiler()->is_c2();
117 }
118 bool nmethod::is_compiled_by_shark() const {
119 if (compiler() == NULL) {
120 return false;
121 }
122 return compiler()->is_shark();
123 }
124
125
126
127 //---------------------------------------------------------------------------------
128 // NMethod statistics
129 // They are printed under various flags, including:
130 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
131 // (In the latter two cases, they like other stats are printed to the log only.)
132
133 #ifndef PRODUCT
134 // These variables are put into one block to reduce relocations
135 // and make it simpler to print from the debugger.
136 struct java_nmethod_stats_struct {
137 int nmethod_count;
138 int total_size;
139 int relocation_size;
140 int consts_size;
141 int insts_size;
142 int stub_size;
143 int scopes_data_size;
144 int scopes_pcs_size;
145 int dependencies_size;
146 int handler_table_size;
147 int nul_chk_table_size;
148 int oops_size;
149 int metadata_size;
150
151 void note_nmethod(nmethod* nm) {
152 nmethod_count += 1;
153 total_size += nm->size();
154 relocation_size += nm->relocation_size();
155 consts_size += nm->consts_size();
156 insts_size += nm->insts_size();
157 stub_size += nm->stub_size();
158 oops_size += nm->oops_size();
159 metadata_size += nm->metadata_size();
160 scopes_data_size += nm->scopes_data_size();
161 scopes_pcs_size += nm->scopes_pcs_size();
162 dependencies_size += nm->dependencies_size();
163 handler_table_size += nm->handler_table_size();
164 nul_chk_table_size += nm->nul_chk_table_size();
165 }
166 void print_nmethod_stats(const char* name) {
167 if (nmethod_count == 0) return;
168 tty->print_cr("Statistics for %d bytecoded nmethods for %s:", nmethod_count, name);
169 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
170 if (nmethod_count != 0) tty->print_cr(" header = " SIZE_FORMAT, nmethod_count * sizeof(nmethod));
171 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
172 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
173 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size);
174 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
175 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
176 if (metadata_size != 0) tty->print_cr(" metadata = %d", metadata_size);
177 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
178 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
179 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
180 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
181 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
182 }
183 };
184
185 struct native_nmethod_stats_struct {
186 int native_nmethod_count;
187 int native_total_size;
188 int native_relocation_size;
189 int native_insts_size;
190 int native_oops_size;
191 int native_metadata_size;
192 void note_native_nmethod(nmethod* nm) {
193 native_nmethod_count += 1;
194 native_total_size += nm->size();
195 native_relocation_size += nm->relocation_size();
196 native_insts_size += nm->insts_size();
197 native_oops_size += nm->oops_size();
198 native_metadata_size += nm->metadata_size();
199 }
200 void print_native_nmethod_stats() {
201 if (native_nmethod_count == 0) return;
202 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
203 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
204 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
205 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size);
206 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
207 if (native_metadata_size != 0) tty->print_cr(" N. metadata = %d", native_metadata_size);
208 }
209 };
210
211 struct pc_nmethod_stats_struct {
212 int pc_desc_resets; // number of resets (= number of caches)
213 int pc_desc_queries; // queries to nmethod::find_pc_desc
214 int pc_desc_approx; // number of those which have approximate true
215 int pc_desc_repeats; // number of _pc_descs[0] hits
216 int pc_desc_hits; // number of LRU cache hits
217 int pc_desc_tests; // total number of PcDesc examinations
218 int pc_desc_searches; // total number of quasi-binary search steps
219 int pc_desc_adds; // number of LUR cache insertions
220
221 void print_pc_stats() {
222 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
223 pc_desc_queries,
224 (double)(pc_desc_tests + pc_desc_searches)
225 / pc_desc_queries);
226 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
227 pc_desc_resets,
228 pc_desc_queries, pc_desc_approx,
229 pc_desc_repeats, pc_desc_hits,
230 pc_desc_tests, pc_desc_searches, pc_desc_adds);
231 }
232 };
233
234 #ifdef COMPILER1
235 static java_nmethod_stats_struct c1_java_nmethod_stats;
236 #endif
237 #ifdef COMPILER2
238 static java_nmethod_stats_struct c2_java_nmethod_stats;
239 #endif
240 #if INCLUDE_JVMCI
241 static java_nmethod_stats_struct jvmci_java_nmethod_stats;
242 #endif
243 #ifdef SHARK
244 static java_nmethod_stats_struct shark_java_nmethod_stats;
245 #endif
246 static java_nmethod_stats_struct unknown_java_nmethod_stats;
247
248 static native_nmethod_stats_struct native_nmethod_stats;
249 static pc_nmethod_stats_struct pc_nmethod_stats;
250
251 static void note_java_nmethod(nmethod* nm) {
252 #ifdef COMPILER1
253 if (nm->is_compiled_by_c1()) {
254 c1_java_nmethod_stats.note_nmethod(nm);
255 } else
256 #endif
257 #ifdef COMPILER2
258 if (nm->is_compiled_by_c2()) {
259 c2_java_nmethod_stats.note_nmethod(nm);
260 } else
261 #endif
262 #if INCLUDE_JVMCI
263 if (nm->is_compiled_by_jvmci()) {
264 jvmci_java_nmethod_stats.note_nmethod(nm);
265 } else
266 #endif
267 #ifdef SHARK
268 if (nm->is_compiled_by_shark()) {
269 shark_java_nmethod_stats.note_nmethod(nm);
270 } else
271 #endif
272 {
273 unknown_java_nmethod_stats.note_nmethod(nm);
274 }
275 }
276 #endif // !PRODUCT
277
278 //---------------------------------------------------------------------------------
279
280
281 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
282 assert(pc != NULL, "Must be non null");
283 assert(exception.not_null(), "Must be non null");
284 assert(handler != NULL, "Must be non null");
285
286 _count = 0;
287 _exception_type = exception->klass();
288 _next = NULL;
289
290 add_address_and_handler(pc,handler);
291 }
292
293
294 address ExceptionCache::match(Handle exception, address pc) {
295 assert(pc != NULL,"Must be non null");
296 assert(exception.not_null(),"Must be non null");
297 if (exception->klass() == exception_type()) {
298 return (test_address(pc));
299 }
300
301 return NULL;
302 }
303
304
305 bool ExceptionCache::match_exception_with_space(Handle exception) {
306 assert(exception.not_null(),"Must be non null");
307 if (exception->klass() == exception_type() && count() < cache_size) {
308 return true;
309 }
310 return false;
311 }
312
313
314 address ExceptionCache::test_address(address addr) {
315 for (int i=0; i<count(); i++) {
316 if (pc_at(i) == addr) {
317 return handler_at(i);
318 }
319 }
320 return NULL;
321 }
322
323
324 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
325 if (test_address(addr) == handler) return true;
326
327 int index = count();
328 if (index < cache_size) {
329 set_pc_at(index, addr);
330 set_handler_at(index, handler);
331 OrderAccess::storestore();
332 increment_count();
333 return true;
334 }
335 return false;
336 }
337
338
339 // private method for handling exception cache
340 // These methods are private, and used to manipulate the exception cache
341 // directly.
342 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
343 ExceptionCache* ec = exception_cache();
344 while (ec != NULL) {
345 if (ec->match_exception_with_space(exception)) {
346 return ec;
347 }
348 ec = ec->next();
349 }
350 return NULL;
351 }
352
353
354 //-----------------------------------------------------------------------------
355
356
357 // Helper used by both find_pc_desc methods.
358 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
359 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_tests);
360 if (!approximate)
361 return pc->pc_offset() == pc_offset;
362 else
363 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
364 }
365
366 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
367 if (initial_pc_desc == NULL) {
368 _pc_descs[0] = NULL; // native method; no PcDescs at all
369 return;
370 }
371 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_resets);
372 // reset the cache by filling it with benign (non-null) values
373 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
374 for (int i = 0; i < cache_size; i++)
375 _pc_descs[i] = initial_pc_desc;
376 }
377
378 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
379 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_queries);
380 NOT_PRODUCT(if (approximate) ++pc_nmethod_stats.pc_desc_approx);
381
382 // Note: one might think that caching the most recently
383 // read value separately would be a win, but one would be
384 // wrong. When many threads are updating it, the cache
385 // line it's in would bounce between caches, negating
386 // any benefit.
387
388 // In order to prevent race conditions do not load cache elements
389 // repeatedly, but use a local copy:
390 PcDesc* res;
391
392 // Step one: Check the most recently added value.
393 res = _pc_descs[0];
394 if (res == NULL) return NULL; // native method; no PcDescs at all
395 if (match_desc(res, pc_offset, approximate)) {
396 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_repeats);
397 return res;
398 }
399
400 // Step two: Check the rest of the LRU cache.
401 for (int i = 1; i < cache_size; ++i) {
402 res = _pc_descs[i];
403 if (res->pc_offset() < 0) break; // optimization: skip empty cache
404 if (match_desc(res, pc_offset, approximate)) {
405 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_hits);
406 return res;
407 }
408 }
409
410 // Report failure.
411 return NULL;
412 }
413
414 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
415 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_adds);
416 // Update the LRU cache by shifting pc_desc forward.
417 for (int i = 0; i < cache_size; i++) {
418 PcDesc* next = _pc_descs[i];
419 _pc_descs[i] = pc_desc;
420 pc_desc = next;
421 }
422 }
423
424 // adjust pcs_size so that it is a multiple of both oopSize and
425 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
426 // of oopSize, then 2*sizeof(PcDesc) is)
427 static int adjust_pcs_size(int pcs_size) {
428 int nsize = round_to(pcs_size, oopSize);
429 if ((nsize % sizeof(PcDesc)) != 0) {
430 nsize = pcs_size + sizeof(PcDesc);
431 }
432 assert((nsize % oopSize) == 0, "correct alignment");
433 return nsize;
434 }
435
436 //-----------------------------------------------------------------------------
437
438
439 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
440 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
441 assert(new_entry != NULL,"Must be non null");
442 assert(new_entry->next() == NULL, "Must be null");
443
444 if (exception_cache() != NULL) {
445 new_entry->set_next(exception_cache());
446 }
447 set_exception_cache(new_entry);
448 }
449
450 void nmethod::clean_exception_cache(BoolObjectClosure* is_alive) {
451 ExceptionCache* prev = NULL;
452 ExceptionCache* curr = exception_cache();
453
454 while (curr != NULL) {
455 ExceptionCache* next = curr->next();
456
457 Klass* ex_klass = curr->exception_type();
458 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
459 if (prev == NULL) {
460 set_exception_cache(next);
461 } else {
462 prev->set_next(next);
463 }
464 delete curr;
465 // prev stays the same.
466 } else {
467 prev = curr;
468 }
469
470 curr = next;
471 }
472 }
473
474 // public method for accessing the exception cache
475 // These are the public access methods.
476 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
477 // We never grab a lock to read the exception cache, so we may
478 // have false negatives. This is okay, as it can only happen during
479 // the first few exception lookups for a given nmethod.
480 ExceptionCache* ec = exception_cache();
481 while (ec != NULL) {
482 address ret_val;
483 if ((ret_val = ec->match(exception,pc)) != NULL) {
484 return ret_val;
485 }
486 ec = ec->next();
487 }
488 return NULL;
489 }
490
491
492 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
493 // There are potential race conditions during exception cache updates, so we
494 // must own the ExceptionCache_lock before doing ANY modifications. Because
495 // we don't lock during reads, it is possible to have several threads attempt
496 // to update the cache with the same data. We need to check for already inserted
497 // copies of the current data before adding it.
498
499 MutexLocker ml(ExceptionCache_lock);
500 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
501
502 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
503 target_entry = new ExceptionCache(exception,pc,handler);
504 add_exception_cache_entry(target_entry);
505 }
506 }
507
508
509 //-------------end of code for ExceptionCache--------------
510
511
512 int nmethod::total_size() const {
513 return
514 consts_size() +
515 insts_size() +
516 stub_size() +
517 scopes_data_size() +
518 scopes_pcs_size() +
519 handler_table_size() +
520 nul_chk_table_size();
521 }
522
523 const char* nmethod::compile_kind() const {
524 if (is_osr_method()) return "osr";
525 if (method() != NULL && is_native_method()) return "c2n";
526 return NULL;
527 }
528
529 // Fill in default values for various flag fields
530 void nmethod::init_defaults() {
531 _state = in_use;
532 _unloading_clock = 0;
533 _marked_for_reclamation = 0;
534 _has_flushed_dependencies = 0;
535 _has_unsafe_access = 0;
536 _has_method_handle_invokes = 0;
537 _lazy_critical_native = 0;
538 _has_wide_vectors = 0;
539 _mark_for_deoptimization_status = not_marked;
540 _lock_count = 0;
541 _stack_traversal_mark = 0;
542 _unload_reported = false; // jvmti state
543
544 #ifdef ASSERT
545 _oops_are_stale = false;
546 #endif
547
548 _oops_do_mark_link = NULL;
549 _jmethod_id = NULL;
550 _osr_link = NULL;
551 if (UseG1GC) {
552 _unloading_next = NULL;
553 } else {
554 _scavenge_root_link = NULL;
555 }
556 _scavenge_root_state = 0;
557 _compiler = NULL;
558 #if INCLUDE_RTM_OPT
559 _rtm_state = NoRTM;
560 #endif
561 #if INCLUDE_JVMCI
562 _jvmci_installed_code = NULL;
563 _speculation_log = NULL;
564 #endif
565 }
566
567 nmethod* nmethod::new_native_nmethod(const methodHandle& method,
568 int compile_id,
569 CodeBuffer *code_buffer,
570 int vep_offset,
571 int frame_complete,
572 int frame_size,
573 ByteSize basic_lock_owner_sp_offset,
574 ByteSize basic_lock_sp_offset,
575 OopMapSet* oop_maps) {
576 code_buffer->finalize_oop_references(method);
577 // create nmethod
578 nmethod* nm = NULL;
579 {
580 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
581 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
582 CodeOffsets offsets;
583 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
584 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
585 nm = new (native_nmethod_size, CompLevel_none) nmethod(method(), native_nmethod_size,
586 compile_id, &offsets,
587 code_buffer, frame_size,
588 basic_lock_owner_sp_offset,
589 basic_lock_sp_offset, oop_maps);
590 NOT_PRODUCT(if (nm != NULL) native_nmethod_stats.note_native_nmethod(nm));
591 }
592 // verify nmethod
593 debug_only(if (nm) nm->verify();) // might block
594
595 if (nm != NULL) {
596 nm->log_new_nmethod();
597 }
598
599 return nm;
600 }
601
602 nmethod* nmethod::new_nmethod(const methodHandle& method,
603 int compile_id,
604 int entry_bci,
605 CodeOffsets* offsets,
606 int orig_pc_offset,
607 DebugInformationRecorder* debug_info,
608 Dependencies* dependencies,
609 CodeBuffer* code_buffer, int frame_size,
610 OopMapSet* oop_maps,
611 ExceptionHandlerTable* handler_table,
612 ImplicitExceptionTable* nul_chk_table,
613 AbstractCompiler* compiler,
614 int comp_level
615 #if INCLUDE_JVMCI
616 , Handle installed_code,
617 Handle speculationLog
618 #endif
619 )
620 {
621 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
622 code_buffer->finalize_oop_references(method);
623 // create nmethod
624 nmethod* nm = NULL;
625 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
626 int nmethod_size =
627 allocation_size(code_buffer, sizeof(nmethod))
628 + adjust_pcs_size(debug_info->pcs_size())
629 + round_to(dependencies->size_in_bytes() , oopSize)
630 + round_to(handler_table->size_in_bytes(), oopSize)
631 + round_to(nul_chk_table->size_in_bytes(), oopSize)
632 + round_to(debug_info->data_size() , oopSize);
633
634 nm = new (nmethod_size, comp_level)
635 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
636 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
637 oop_maps,
638 handler_table,
639 nul_chk_table,
640 compiler,
641 comp_level
642 #if INCLUDE_JVMCI
643 , installed_code,
644 speculationLog
645 #endif
646 );
647
648 if (nm != NULL) {
649 // To make dependency checking during class loading fast, record
650 // the nmethod dependencies in the classes it is dependent on.
651 // This allows the dependency checking code to simply walk the
652 // class hierarchy above the loaded class, checking only nmethods
653 // which are dependent on those classes. The slow way is to
654 // check every nmethod for dependencies which makes it linear in
655 // the number of methods compiled. For applications with a lot
656 // classes the slow way is too slow.
657 for (Dependencies::DepStream deps(nm); deps.next(); ) {
658 if (deps.type() == Dependencies::call_site_target_value) {
659 // CallSite dependencies are managed on per-CallSite instance basis.
660 oop call_site = deps.argument_oop(0);
661 MethodHandles::add_dependent_nmethod(call_site, nm);
662 } else {
663 Klass* klass = deps.context_type();
664 if (klass == NULL) {
665 continue; // ignore things like evol_method
666 }
667 // record this nmethod as dependent on this klass
668 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
669 }
670 }
671 NOT_PRODUCT(if (nm != NULL) note_java_nmethod(nm));
672 }
673 }
674 // Do verification and logging outside CodeCache_lock.
675 if (nm != NULL) {
676 // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
677 DEBUG_ONLY(nm->verify();)
678 nm->log_new_nmethod();
679 }
680 return nm;
681 }
682
683 // For native wrappers
684 nmethod::nmethod(
685 Method* method,
686 int nmethod_size,
687 int compile_id,
688 CodeOffsets* offsets,
689 CodeBuffer* code_buffer,
690 int frame_size,
691 ByteSize basic_lock_owner_sp_offset,
692 ByteSize basic_lock_sp_offset,
693 OopMapSet* oop_maps )
694 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
695 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
696 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
697 _native_basic_lock_sp_offset(basic_lock_sp_offset)
698 {
699 {
700 debug_only(NoSafepointVerifier nsv;)
701 assert_locked_or_safepoint(CodeCache_lock);
702
703 init_defaults();
704 _method = method;
705 _entry_bci = InvocationEntryBci;
706 // We have no exception handler or deopt handler make the
707 // values something that will never match a pc like the nmethod vtable entry
708 _exception_offset = 0;
709 _deoptimize_offset = 0;
710 _deoptimize_mh_offset = 0;
711 _orig_pc_offset = 0;
712
713 _consts_offset = data_offset();
714 _stub_offset = data_offset();
715 _oops_offset = data_offset();
716 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
717 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
718 _scopes_pcs_offset = _scopes_data_offset;
719 _dependencies_offset = _scopes_pcs_offset;
720 _handler_table_offset = _dependencies_offset;
721 _nul_chk_table_offset = _handler_table_offset;
722 _nmethod_end_offset = _nul_chk_table_offset;
723 _compile_id = compile_id;
724 _comp_level = CompLevel_none;
725 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
726 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
727 _osr_entry_point = NULL;
728 _exception_cache = NULL;
729 _pc_desc_cache.reset_to(NULL);
730 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
731
732 code_buffer->copy_values_to(this);
733 if (ScavengeRootsInCode) {
734 if (detect_scavenge_root_oops()) {
735 CodeCache::add_scavenge_root_nmethod(this);
736 }
737 Universe::heap()->register_nmethod(this);
738 }
739 debug_only(verify_scavenge_root_oops());
740 CodeCache::commit(this);
741 }
742
743 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
744 ttyLocker ttyl; // keep the following output all in one block
745 // This output goes directly to the tty, not the compiler log.
746 // To enable tools to match it up with the compilation activity,
747 // be sure to tag this tty output with the compile ID.
748 if (xtty != NULL) {
749 xtty->begin_head("print_native_nmethod");
750 xtty->method(_method);
751 xtty->stamp();
752 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
753 }
754 // print the header part first
755 print();
756 // then print the requested information
757 if (PrintNativeNMethods) {
758 print_code();
759 if (oop_maps != NULL) {
760 oop_maps->print();
761 }
762 }
763 if (PrintRelocations) {
764 print_relocations();
765 }
766 if (xtty != NULL) {
767 xtty->tail("print_native_nmethod");
768 }
769 }
770 }
771
772 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
773 return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
774 }
775
776 nmethod::nmethod(
777 Method* method,
778 int nmethod_size,
779 int compile_id,
780 int entry_bci,
781 CodeOffsets* offsets,
782 int orig_pc_offset,
783 DebugInformationRecorder* debug_info,
784 Dependencies* dependencies,
785 CodeBuffer *code_buffer,
786 int frame_size,
787 OopMapSet* oop_maps,
788 ExceptionHandlerTable* handler_table,
789 ImplicitExceptionTable* nul_chk_table,
790 AbstractCompiler* compiler,
791 int comp_level
792 #if INCLUDE_JVMCI
793 , Handle installed_code,
794 Handle speculation_log
795 #endif
796 )
797 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
798 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
799 _native_receiver_sp_offset(in_ByteSize(-1)),
800 _native_basic_lock_sp_offset(in_ByteSize(-1))
801 {
802 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
803 {
804 debug_only(NoSafepointVerifier nsv;)
805 assert_locked_or_safepoint(CodeCache_lock);
806
807 init_defaults();
808 _method = method;
809 _entry_bci = entry_bci;
810 _compile_id = compile_id;
811 _comp_level = comp_level;
812 _compiler = compiler;
813 _orig_pc_offset = orig_pc_offset;
814 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
815
816 // Section offsets
817 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
818 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
819
820 #if INCLUDE_JVMCI
821 _jvmci_installed_code = installed_code();
822 _speculation_log = (instanceOop)speculation_log();
823
824 if (compiler->is_jvmci()) {
825 // JVMCI might not produce any stub sections
826 if (offsets->value(CodeOffsets::Exceptions) != -1) {
827 _exception_offset = code_offset() + offsets->value(CodeOffsets::Exceptions);
828 } else {
829 _exception_offset = -1;
830 }
831 if (offsets->value(CodeOffsets::Deopt) != -1) {
832 _deoptimize_offset = code_offset() + offsets->value(CodeOffsets::Deopt);
833 } else {
834 _deoptimize_offset = -1;
835 }
836 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
837 _deoptimize_mh_offset = code_offset() + offsets->value(CodeOffsets::DeoptMH);
838 } else {
839 _deoptimize_mh_offset = -1;
840 }
841 } else {
842 #endif
843 // Exception handler and deopt handler are in the stub section
844 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
845 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
846
847 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
848 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
849 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
850 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
851 } else {
852 _deoptimize_mh_offset = -1;
853 #if INCLUDE_JVMCI
854 }
855 #endif
856 }
857 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
858 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
859 } else {
860 _unwind_handler_offset = -1;
861 }
862
863 _oops_offset = data_offset();
864 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
865 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
866
867 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
868 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
869 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
870 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
871 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
872
873 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
874 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
875 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
876 _exception_cache = NULL;
877 _pc_desc_cache.reset_to(scopes_pcs_begin());
878
879 // Copy contents of ScopeDescRecorder to nmethod
880 code_buffer->copy_values_to(this);
881 debug_info->copy_to(this);
882 dependencies->copy_to(this);
883 if (ScavengeRootsInCode) {
884 if (detect_scavenge_root_oops()) {
885 CodeCache::add_scavenge_root_nmethod(this);
886 }
887 Universe::heap()->register_nmethod(this);
888 }
889 debug_only(verify_scavenge_root_oops());
890
891 CodeCache::commit(this);
892
893 // Copy contents of ExceptionHandlerTable to nmethod
894 handler_table->copy_to(this);
895 nul_chk_table->copy_to(this);
896
897 // we use the information of entry points to find out if a method is
898 // static or non static
899 assert(compiler->is_c2() || compiler->is_jvmci() ||
900 _method->is_static() == (entry_point() == _verified_entry_point),
901 " entry points must be same for static methods and vice versa");
902 }
903 }
904
905 // Print a short set of xml attributes to identify this nmethod. The
906 // output should be embedded in some other element.
907 void nmethod::log_identity(xmlStream* log) const {
908 log->print(" compile_id='%d'", compile_id());
909 const char* nm_kind = compile_kind();
910 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
911 if (compiler() != NULL) {
912 log->print(" compiler='%s'", compiler()->name());
913 }
914 if (TieredCompilation) {
915 log->print(" level='%d'", comp_level());
916 }
917 }
918
919
920 #define LOG_OFFSET(log, name) \
921 if (p2i(name##_end()) - p2i(name##_begin())) \
922 log->print(" " XSTR(name) "_offset='" INTX_FORMAT "'" , \
923 p2i(name##_begin()) - p2i(this))
924
925
926 void nmethod::log_new_nmethod() const {
927 if (LogCompilation && xtty != NULL) {
928 ttyLocker ttyl;
929 HandleMark hm;
930 xtty->begin_elem("nmethod");
931 log_identity(xtty);
932 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", p2i(code_begin()), size());
933 xtty->print(" address='" INTPTR_FORMAT "'", p2i(this));
934
935 LOG_OFFSET(xtty, relocation);
936 LOG_OFFSET(xtty, consts);
937 LOG_OFFSET(xtty, insts);
938 LOG_OFFSET(xtty, stub);
939 LOG_OFFSET(xtty, scopes_data);
940 LOG_OFFSET(xtty, scopes_pcs);
941 LOG_OFFSET(xtty, dependencies);
942 LOG_OFFSET(xtty, handler_table);
943 LOG_OFFSET(xtty, nul_chk_table);
944 LOG_OFFSET(xtty, oops);
945 LOG_OFFSET(xtty, metadata);
946
947 xtty->method(method());
948 xtty->stamp();
949 xtty->end_elem();
950 }
951 }
952
953 #undef LOG_OFFSET
954
955
956 // Print out more verbose output usually for a newly created nmethod.
957 void nmethod::print_on(outputStream* st, const char* msg) const {
958 if (st != NULL) {
959 ttyLocker ttyl;
960 if (WizardMode) {
961 CompileTask::print(st, this, msg, /*short_form:*/ true);
962 st->print_cr(" (" INTPTR_FORMAT ")", p2i(this));
963 } else {
964 CompileTask::print(st, this, msg, /*short_form:*/ false);
965 }
966 }
967 }
968
969 void nmethod::maybe_print_nmethod(DirectiveSet* directive) {
970 bool printnmethods = directive->PrintAssemblyOption || directive->PrintNMethodsOption;
971 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
972 print_nmethod(printnmethods);
973 }
974 }
975
976 void nmethod::print_nmethod(bool printmethod) {
977 ttyLocker ttyl; // keep the following output all in one block
978 if (xtty != NULL) {
979 xtty->begin_head("print_nmethod");
980 xtty->stamp();
981 xtty->end_head();
982 }
983 // print the header part first
984 print();
985 // then print the requested information
986 if (printmethod) {
987 print_code();
988 print_pcs();
989 if (oop_maps()) {
990 oop_maps()->print();
991 }
992 }
993 if (printmethod || PrintDebugInfo || CompilerOracle::has_option_string(_method, "PrintDebugInfo")) {
994 print_scopes();
995 }
996 if (printmethod || PrintRelocations || CompilerOracle::has_option_string(_method, "PrintRelocations")) {
997 print_relocations();
998 }
999 if (printmethod || PrintDependencies || CompilerOracle::has_option_string(_method, "PrintDependencies")) {
1000 print_dependencies();
1001 }
1002 if (printmethod || PrintExceptionHandlers) {
1003 print_handler_table();
1004 print_nul_chk_table();
1005 }
1006 if (printmethod) {
1007 print_recorded_oops();
1008 print_recorded_metadata();
1009 }
1010 if (xtty != NULL) {
1011 xtty->tail("print_nmethod");
1012 }
1013 }
1014
1015
1016 // Promote one word from an assembly-time handle to a live embedded oop.
1017 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1018 if (handle == NULL ||
1019 // As a special case, IC oops are initialized to 1 or -1.
1020 handle == (jobject) Universe::non_oop_word()) {
1021 (*dest) = (oop) handle;
1022 } else {
1023 (*dest) = JNIHandles::resolve_non_null(handle);
1024 }
1025 }
1026
1027
1028 // Have to have the same name because it's called by a template
1029 void nmethod::copy_values(GrowableArray<jobject>* array) {
1030 int length = array->length();
1031 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1032 oop* dest = oops_begin();
1033 for (int index = 0 ; index < length; index++) {
1034 initialize_immediate_oop(&dest[index], array->at(index));
1035 }
1036
1037 // Now we can fix up all the oops in the code. We need to do this
1038 // in the code because the assembler uses jobjects as placeholders.
1039 // The code and relocations have already been initialized by the
1040 // CodeBlob constructor, so it is valid even at this early point to
1041 // iterate over relocations and patch the code.
1042 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1043 }
1044
1045 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1046 int length = array->length();
1047 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1048 Metadata** dest = metadata_begin();
1049 for (int index = 0 ; index < length; index++) {
1050 dest[index] = array->at(index);
1051 }
1052 }
1053
1054 bool nmethod::is_at_poll_return(address pc) {
1055 RelocIterator iter(this, pc, pc+1);
1056 while (iter.next()) {
1057 if (iter.type() == relocInfo::poll_return_type)
1058 return true;
1059 }
1060 return false;
1061 }
1062
1063
1064 bool nmethod::is_at_poll_or_poll_return(address pc) {
1065 RelocIterator iter(this, pc, pc+1);
1066 while (iter.next()) {
1067 relocInfo::relocType t = iter.type();
1068 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1069 return true;
1070 }
1071 return false;
1072 }
1073
1074
1075 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1076 // re-patch all oop-bearing instructions, just in case some oops moved
1077 RelocIterator iter(this, begin, end);
1078 while (iter.next()) {
1079 if (iter.type() == relocInfo::oop_type) {
1080 oop_Relocation* reloc = iter.oop_reloc();
1081 if (initialize_immediates && reloc->oop_is_immediate()) {
1082 oop* dest = reloc->oop_addr();
1083 initialize_immediate_oop(dest, (jobject) *dest);
1084 }
1085 // Refresh the oop-related bits of this instruction.
1086 reloc->fix_oop_relocation();
1087 } else if (iter.type() == relocInfo::metadata_type) {
1088 metadata_Relocation* reloc = iter.metadata_reloc();
1089 reloc->fix_metadata_relocation();
1090 }
1091 }
1092 }
1093
1094
1095 void nmethod::verify_oop_relocations() {
1096 // Ensure sure that the code matches the current oop values
1097 RelocIterator iter(this, NULL, NULL);
1098 while (iter.next()) {
1099 if (iter.type() == relocInfo::oop_type) {
1100 oop_Relocation* reloc = iter.oop_reloc();
1101 if (!reloc->oop_is_immediate()) {
1102 reloc->verify_oop_relocation();
1103 }
1104 }
1105 }
1106 }
1107
1108
1109 ScopeDesc* nmethod::scope_desc_at(address pc) {
1110 PcDesc* pd = pc_desc_at(pc);
1111 guarantee(pd != NULL, "scope must be present");
1112 return new ScopeDesc(this, pd->scope_decode_offset(),
1113 pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(),
1114 pd->return_oop());
1115 }
1116
1117
1118 void nmethod::clear_inline_caches() {
1119 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1120 if (is_zombie()) {
1121 return;
1122 }
1123
1124 RelocIterator iter(this);
1125 while (iter.next()) {
1126 iter.reloc()->clear_inline_cache();
1127 }
1128 }
1129
1130 // Clear ICStubs of all compiled ICs
1131 void nmethod::clear_ic_stubs() {
1132 assert_locked_or_safepoint(CompiledIC_lock);
1133 RelocIterator iter(this);
1134 while(iter.next()) {
1135 if (iter.type() == relocInfo::virtual_call_type) {
1136 CompiledIC* ic = CompiledIC_at(&iter);
1137 ic->clear_ic_stub();
1138 }
1139 }
1140 }
1141
1142
1143 void nmethod::cleanup_inline_caches() {
1144 assert_locked_or_safepoint(CompiledIC_lock);
1145
1146 // If the method is not entrant or zombie then a JMP is plastered over the
1147 // first few bytes. If an oop in the old code was there, that oop
1148 // should not get GC'd. Skip the first few bytes of oops on
1149 // not-entrant methods.
1150 address low_boundary = verified_entry_point();
1151 if (!is_in_use()) {
1152 low_boundary += NativeJump::instruction_size;
1153 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1154 // This means that the low_boundary is going to be a little too high.
1155 // This shouldn't matter, since oops of non-entrant methods are never used.
1156 // In fact, why are we bothering to look at oops in a non-entrant method??
1157 }
1158
1159 // Find all calls in an nmethod and clear the ones that point to non-entrant,
1160 // zombie and unloaded nmethods.
1161 ResourceMark rm;
1162 RelocIterator iter(this, low_boundary);
1163 while(iter.next()) {
1164 switch(iter.type()) {
1165 case relocInfo::virtual_call_type:
1166 case relocInfo::opt_virtual_call_type: {
1167 CompiledIC *ic = CompiledIC_at(&iter);
1168 // Ok, to lookup references to zombies here
1169 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1170 if( cb != NULL && cb->is_nmethod() ) {
1171 nmethod* nm = (nmethod*)cb;
1172 // Clean inline caches pointing to zombie, non-entrant and unloaded methods
1173 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean(is_alive());
1174 }
1175 break;
1176 }
1177 case relocInfo::static_call_type: {
1178 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1179 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1180 if( cb != NULL && cb->is_nmethod() ) {
1181 nmethod* nm = (nmethod*)cb;
1182 // Clean inline caches pointing to zombie, non-entrant and unloaded methods
1183 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1184 }
1185 break;
1186 }
1187 }
1188 }
1189 }
1190
1191 void nmethod::verify_clean_inline_caches() {
1192 assert_locked_or_safepoint(CompiledIC_lock);
1193
1194 // If the method is not entrant or zombie then a JMP is plastered over the
1195 // first few bytes. If an oop in the old code was there, that oop
1196 // should not get GC'd. Skip the first few bytes of oops on
1197 // not-entrant methods.
1198 address low_boundary = verified_entry_point();
1199 if (!is_in_use()) {
1200 low_boundary += NativeJump::instruction_size;
1201 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1202 // This means that the low_boundary is going to be a little too high.
1203 // This shouldn't matter, since oops of non-entrant methods are never used.
1204 // In fact, why are we bothering to look at oops in a non-entrant method??
1205 }
1206
1207 ResourceMark rm;
1208 RelocIterator iter(this, low_boundary);
1209 while(iter.next()) {
1210 switch(iter.type()) {
1211 case relocInfo::virtual_call_type:
1212 case relocInfo::opt_virtual_call_type: {
1213 CompiledIC *ic = CompiledIC_at(&iter);
1214 // Ok, to lookup references to zombies here
1215 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1216 if( cb != NULL && cb->is_nmethod() ) {
1217 nmethod* nm = (nmethod*)cb;
1218 // Verify that inline caches pointing to both zombie and not_entrant methods are clean
1219 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1220 assert(ic->is_clean(), "IC should be clean");
1221 }
1222 }
1223 break;
1224 }
1225 case relocInfo::static_call_type: {
1226 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1227 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1228 if( cb != NULL && cb->is_nmethod() ) {
1229 nmethod* nm = (nmethod*)cb;
1230 // Verify that inline caches pointing to both zombie and not_entrant methods are clean
1231 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1232 assert(csc->is_clean(), "IC should be clean");
1233 }
1234 }
1235 break;
1236 }
1237 }
1238 }
1239 }
1240
1241 int nmethod::verify_icholder_relocations() {
1242 int count = 0;
1243
1244 RelocIterator iter(this);
1245 while(iter.next()) {
1246 if (iter.type() == relocInfo::virtual_call_type) {
1247 if (CompiledIC::is_icholder_call_site(iter.virtual_call_reloc())) {
1248 CompiledIC *ic = CompiledIC_at(&iter);
1249 if (TraceCompiledIC) {
1250 tty->print("noticed icholder " INTPTR_FORMAT " ", p2i(ic->cached_icholder()));
1251 ic->print();
1252 }
1253 assert(ic->cached_icholder() != NULL, "must be non-NULL");
1254 count++;
1255 }
1256 }
1257 }
1258
1259 return count;
1260 }
1261
1262 // This is a private interface with the sweeper.
1263 void nmethod::mark_as_seen_on_stack() {
1264 assert(is_alive(), "Must be an alive method");
1265 // Set the traversal mark to ensure that the sweeper does 2
1266 // cleaning passes before moving to zombie.
1267 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1268 }
1269
1270 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1271 // there are no activations on the stack, not in use by the VM,
1272 // and not in use by the ServiceThread)
1273 bool nmethod::can_convert_to_zombie() {
1274 assert(is_not_entrant(), "must be a non-entrant method");
1275
1276 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1277 // count can be greater than the stack traversal count before it hits the
1278 // nmethod for the second time.
1279 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1280 !is_locked_by_vm();
1281 }
1282
1283 void nmethod::inc_decompile_count() {
1284 if (!is_compiled_by_c2() && !is_compiled_by_jvmci()) return;
1285 // Could be gated by ProfileTraps, but do not bother...
1286 Method* m = method();
1287 if (m == NULL) return;
1288 MethodData* mdo = m->method_data();
1289 if (mdo == NULL) return;
1290 // There is a benign race here. See comments in methodData.hpp.
1291 mdo->inc_decompile_count();
1292 }
1293
1294 void nmethod::increase_unloading_clock() {
1295 _global_unloading_clock++;
1296 if (_global_unloading_clock == 0) {
1297 // _nmethods are allocated with _unloading_clock == 0,
1298 // so 0 is never used as a clock value.
1299 _global_unloading_clock = 1;
1300 }
1301 }
1302
1303 void nmethod::set_unloading_clock(unsigned char unloading_clock) {
1304 OrderAccess::release_store((volatile jubyte*)&_unloading_clock, unloading_clock);
1305 }
1306
1307 unsigned char nmethod::unloading_clock() {
1308 return (unsigned char)OrderAccess::load_acquire((volatile jubyte*)&_unloading_clock);
1309 }
1310
1311 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1312
1313 post_compiled_method_unload();
1314
1315 // Since this nmethod is being unloaded, make sure that dependencies
1316 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1317 // indicate that this work is being done during a GC.
1318 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1319 assert(is_alive != NULL, "Should be non-NULL");
1320 // A non-NULL is_alive closure indicates that this is being called during GC.
1321 flush_dependencies(is_alive);
1322
1323 // Break cycle between nmethod & method
1324 if (log_is_enabled(Trace, classunload)) {
1325 outputStream* log = LogHandle(classunload)::trace_stream();
1326 log->print_cr("making nmethod " INTPTR_FORMAT
1327 " unloadable, Method*(" INTPTR_FORMAT
1328 "), cause(" INTPTR_FORMAT ")",
1329 p2i(this), p2i(_method), p2i(cause));
1330 if (!Universe::heap()->is_gc_active())
1331 cause->klass()->print_on(log);
1332 }
1333 // Unlink the osr method, so we do not look this up again
1334 if (is_osr_method()) {
1335 invalidate_osr_method();
1336 }
1337 // If _method is already NULL the Method* is about to be unloaded,
1338 // so we don't have to break the cycle. Note that it is possible to
1339 // have the Method* live here, in case we unload the nmethod because
1340 // it is pointing to some oop (other than the Method*) being unloaded.
1341 if (_method != NULL) {
1342 // OSR methods point to the Method*, but the Method* does not
1343 // point back!
1344 if (_method->code() == this) {
1345 _method->clear_code(); // Break a cycle
1346 }
1347 _method = NULL; // Clear the method of this dead nmethod
1348 }
1349
1350 // Make the class unloaded - i.e., change state and notify sweeper
1351 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1352 if (is_in_use()) {
1353 // Transitioning directly from live to unloaded -- so
1354 // we need to force a cache clean-up; remember this
1355 // for later on.
1356 CodeCache::set_needs_cache_clean(true);
1357 }
1358
1359 // Unregister must be done before the state change
1360 Universe::heap()->unregister_nmethod(this);
1361
1362 _state = unloaded;
1363
1364 // Log the unloading.
1365 log_state_change();
1366
1367 #if INCLUDE_JVMCI
1368 // The method can only be unloaded after the pointer to the installed code
1369 // Java wrapper is no longer alive. Here we need to clear out this weak
1370 // reference to the dead object. Nulling out the reference has to happen
1371 // after the method is unregistered since the original value may be still
1372 // tracked by the rset.
1373 maybe_invalidate_installed_code();
1374 // Clear these out after the nmethod has been unregistered and any
1375 // updates to the InstalledCode instance have been performed.
1376 _jvmci_installed_code = NULL;
1377 _speculation_log = NULL;
1378 #endif
1379
1380 // The Method* is gone at this point
1381 assert(_method == NULL, "Tautology");
1382
1383 set_osr_link(NULL);
1384 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1385 NMethodSweeper::report_state_change(this);
1386 }
1387
1388 void nmethod::invalidate_osr_method() {
1389 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1390 #ifndef ASSERT
1391 // Make sure osr nmethod is invalidated only once
1392 if (!is_in_use()) {
1393 return;
1394 }
1395 #endif
1396 // Remove from list of active nmethods
1397 if (method() != NULL) {
1398 bool removed = method()->method_holder()->remove_osr_nmethod(this);
1399 assert(!removed || is_in_use(), "unused osr nmethod should be invalidated");
1400 }
1401 }
1402
1403 void nmethod::log_state_change() const {
1404 if (LogCompilation) {
1405 if (xtty != NULL) {
1406 ttyLocker ttyl; // keep the following output all in one block
1407 if (_state == unloaded) {
1408 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1409 os::current_thread_id());
1410 } else {
1411 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1412 os::current_thread_id(),
1413 (_state == zombie ? " zombie='1'" : ""));
1414 }
1415 log_identity(xtty);
1416 xtty->stamp();
1417 xtty->end_elem();
1418 }
1419 }
1420 if (PrintCompilation && _state != unloaded) {
1421 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1422 }
1423 }
1424
1425 /**
1426 * Common functionality for both make_not_entrant and make_zombie
1427 */
1428 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1429 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1430 assert(!is_zombie(), "should not already be a zombie");
1431
1432 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1433 nmethodLocker nml(this);
1434 methodHandle the_method(method());
1435 NoSafepointVerifier nsv;
1436
1437 // during patching, depending on the nmethod state we must notify the GC that
1438 // code has been unloaded, unregistering it. We cannot do this right while
1439 // holding the Patching_lock because we need to use the CodeCache_lock. This
1440 // would be prone to deadlocks.
1441 // This flag is used to remember whether we need to later lock and unregister.
1442 bool nmethod_needs_unregister = false;
1443
1444 {
1445 // invalidate osr nmethod before acquiring the patching lock since
1446 // they both acquire leaf locks and we don't want a deadlock.
1447 // This logic is equivalent to the logic below for patching the
1448 // verified entry point of regular methods.
1449 if (is_osr_method()) {
1450 // this effectively makes the osr nmethod not entrant
1451 invalidate_osr_method();
1452 }
1453
1454 // Enter critical section. Does not block for safepoint.
1455 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1456
1457 if (_state == state) {
1458 // another thread already performed this transition so nothing
1459 // to do, but return false to indicate this.
1460 return false;
1461 }
1462
1463 // The caller can be calling the method statically or through an inline
1464 // cache call.
1465 if (!is_osr_method() && !is_not_entrant()) {
1466 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1467 SharedRuntime::get_handle_wrong_method_stub());
1468 }
1469
1470 if (is_in_use() && update_recompile_counts()) {
1471 // It's a true state change, so mark the method as decompiled.
1472 // Do it only for transition from alive.
1473 inc_decompile_count();
1474 }
1475
1476 // If the state is becoming a zombie, signal to unregister the nmethod with
1477 // the heap.
1478 // This nmethod may have already been unloaded during a full GC.
1479 if ((state == zombie) && !is_unloaded()) {
1480 nmethod_needs_unregister = true;
1481 }
1482
1483 // Must happen before state change. Otherwise we have a race condition in
1484 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1485 // transition its state from 'not_entrant' to 'zombie' without having to wait
1486 // for stack scanning.
1487 if (state == not_entrant) {
1488 mark_as_seen_on_stack();
1489 OrderAccess::storestore();
1490 }
1491
1492 // Change state
1493 _state = state;
1494
1495 // Log the transition once
1496 log_state_change();
1497
1498 // Invalidate while holding the patching lock
1499 JVMCI_ONLY(maybe_invalidate_installed_code());
1500
1501 // Remove nmethod from method.
1502 // We need to check if both the _code and _from_compiled_code_entry_point
1503 // refer to this nmethod because there is a race in setting these two fields
1504 // in Method* as seen in bugid 4947125.
1505 // If the vep() points to the zombie nmethod, the memory for the nmethod
1506 // could be flushed and the compiler and vtable stubs could still call
1507 // through it.
1508 if (method() != NULL && (method()->code() == this ||
1509 method()->from_compiled_entry() == verified_entry_point())) {
1510 HandleMark hm;
1511 method()->clear_code();
1512 }
1513 } // leave critical region under Patching_lock
1514
1515 // When the nmethod becomes zombie it is no longer alive so the
1516 // dependencies must be flushed. nmethods in the not_entrant
1517 // state will be flushed later when the transition to zombie
1518 // happens or they get unloaded.
1519 if (state == zombie) {
1520 {
1521 // Flushing dependencies must be done before any possible
1522 // safepoint can sneak in, otherwise the oops used by the
1523 // dependency logic could have become stale.
1524 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1525 if (nmethod_needs_unregister) {
1526 Universe::heap()->unregister_nmethod(this);
1527 #ifdef JVMCI
1528 _jvmci_installed_code = NULL;
1529 _speculation_log = NULL;
1530 #endif
1531 }
1532 flush_dependencies(NULL);
1533 }
1534
1535 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1536 // event and it hasn't already been reported for this nmethod then
1537 // report it now. The event may have been reported earlier if the GC
1538 // marked it for unloading). JvmtiDeferredEventQueue support means
1539 // we no longer go to a safepoint here.
1540 post_compiled_method_unload();
1541
1542 #ifdef ASSERT
1543 // It's no longer safe to access the oops section since zombie
1544 // nmethods aren't scanned for GC.
1545 _oops_are_stale = true;
1546 #endif
1547 // the Method may be reclaimed by class unloading now that the
1548 // nmethod is in zombie state
1549 set_method(NULL);
1550 } else {
1551 assert(state == not_entrant, "other cases may need to be handled differently");
1552 }
1553
1554 if (TraceCreateZombies) {
1555 ResourceMark m;
1556 tty->print_cr("nmethod <" INTPTR_FORMAT "> %s code made %s", p2i(this), this->method() ? this->method()->name_and_sig_as_C_string() : "null", (state == not_entrant) ? "not entrant" : "zombie");
1557 }
1558
1559 NMethodSweeper::report_state_change(this);
1560 return true;
1561 }
1562
1563 void nmethod::flush() {
1564 // Note that there are no valid oops in the nmethod anymore.
1565 assert(!is_osr_method() || is_unloaded() || is_zombie(),
1566 "osr nmethod must be unloaded or zombie before flushing");
1567 assert(is_zombie() || is_osr_method(), "must be a zombie method");
1568 assert(is_marked_for_reclamation() || is_osr_method(), "must be marked for reclamation");
1569
1570 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1571 assert_locked_or_safepoint(CodeCache_lock);
1572
1573 // completely deallocate this method
1574 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, p2i(this));
1575 if (PrintMethodFlushing) {
1576 tty->print_cr("*flushing %s nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT
1577 "/Free CodeCache:" SIZE_FORMAT "Kb",
1578 is_osr_method() ? "osr" : "",_compile_id, p2i(this), CodeCache::blob_count(),
1579 CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(this))/1024);
1580 }
1581
1582 // We need to deallocate any ExceptionCache data.
1583 // Note that we do not need to grab the nmethod lock for this, it
1584 // better be thread safe if we're disposing of it!
1585 ExceptionCache* ec = exception_cache();
1586 set_exception_cache(NULL);
1587 while(ec != NULL) {
1588 ExceptionCache* next = ec->next();
1589 delete ec;
1590 ec = next;
1591 }
1592
1593 if (on_scavenge_root_list()) {
1594 CodeCache::drop_scavenge_root_nmethod(this);
1595 }
1596
1597 #ifdef SHARK
1598 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1599 #endif // SHARK
1600
1601 ((CodeBlob*)(this))->flush();
1602
1603 CodeCache::free(this);
1604 }
1605
1606 //
1607 // Notify all classes this nmethod is dependent on that it is no
1608 // longer dependent. This should only be called in two situations.
1609 // First, when a nmethod transitions to a zombie all dependents need
1610 // to be clear. Since zombification happens at a safepoint there's no
1611 // synchronization issues. The second place is a little more tricky.
1612 // During phase 1 of mark sweep class unloading may happen and as a
1613 // result some nmethods may get unloaded. In this case the flushing
1614 // of dependencies must happen during phase 1 since after GC any
1615 // dependencies in the unloaded nmethod won't be updated, so
1616 // traversing the dependency information in unsafe. In that case this
1617 // function is called with a non-NULL argument and this function only
1618 // notifies instanceKlasses that are reachable
1619
1620 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1621 assert_locked_or_safepoint(CodeCache_lock);
1622 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1623 "is_alive is non-NULL if and only if we are called during GC");
1624 if (!has_flushed_dependencies()) {
1625 set_has_flushed_dependencies();
1626 for (Dependencies::DepStream deps(this); deps.next(); ) {
1627 if (deps.type() == Dependencies::call_site_target_value) {
1628 // CallSite dependencies are managed on per-CallSite instance basis.
1629 oop call_site = deps.argument_oop(0);
1630 MethodHandles::remove_dependent_nmethod(call_site, this);
1631 } else {
1632 Klass* klass = deps.context_type();
1633 if (klass == NULL) {
1634 continue; // ignore things like evol_method
1635 }
1636 // During GC the is_alive closure is non-NULL, and is used to
1637 // determine liveness of dependees that need to be updated.
1638 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1639 // The GC defers deletion of this entry, since there might be multiple threads
1640 // iterating over the _dependencies graph. Other call paths are single-threaded
1641 // and may delete it immediately.
1642 bool delete_immediately = is_alive == NULL;
1643 InstanceKlass::cast(klass)->remove_dependent_nmethod(this, delete_immediately);
1644 }
1645 }
1646 }
1647 }
1648 }
1649
1650
1651 // If this oop is not live, the nmethod can be unloaded.
1652 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1653 assert(root != NULL, "just checking");
1654 oop obj = *root;
1655 if (obj == NULL || is_alive->do_object_b(obj)) {
1656 return false;
1657 }
1658
1659 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1660 // simply because one of its constant oops has gone dead.
1661 // No actual classes need to be unloaded in order for this to occur.
1662 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1663 make_unloaded(is_alive, obj);
1664 return true;
1665 }
1666
1667 // ------------------------------------------------------------------
1668 // post_compiled_method_load_event
1669 // new method for install_code() path
1670 // Transfer information from compilation to jvmti
1671 void nmethod::post_compiled_method_load_event() {
1672
1673 Method* moop = method();
1674 HOTSPOT_COMPILED_METHOD_LOAD(
1675 (char *) moop->klass_name()->bytes(),
1676 moop->klass_name()->utf8_length(),
1677 (char *) moop->name()->bytes(),
1678 moop->name()->utf8_length(),
1679 (char *) moop->signature()->bytes(),
1680 moop->signature()->utf8_length(),
1681 insts_begin(), insts_size());
1682
1683 if (JvmtiExport::should_post_compiled_method_load() ||
1684 JvmtiExport::should_post_compiled_method_unload()) {
1685 get_and_cache_jmethod_id();
1686 }
1687
1688 if (JvmtiExport::should_post_compiled_method_load()) {
1689 // Let the Service thread (which is a real Java thread) post the event
1690 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1691 JvmtiDeferredEventQueue::enqueue(
1692 JvmtiDeferredEvent::compiled_method_load_event(this));
1693 }
1694 }
1695
1696 jmethodID nmethod::get_and_cache_jmethod_id() {
1697 if (_jmethod_id == NULL) {
1698 // Cache the jmethod_id since it can no longer be looked up once the
1699 // method itself has been marked for unloading.
1700 _jmethod_id = method()->jmethod_id();
1701 }
1702 return _jmethod_id;
1703 }
1704
1705 void nmethod::post_compiled_method_unload() {
1706 if (unload_reported()) {
1707 // During unloading we transition to unloaded and then to zombie
1708 // and the unloading is reported during the first transition.
1709 return;
1710 }
1711
1712 assert(_method != NULL && !is_unloaded(), "just checking");
1713 DTRACE_METHOD_UNLOAD_PROBE(method());
1714
1715 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1716 // post the event. Sometime later this nmethod will be made a zombie
1717 // by the sweeper but the Method* will not be valid at that point.
1718 // If the _jmethod_id is null then no load event was ever requested
1719 // so don't bother posting the unload. The main reason for this is
1720 // that the jmethodID is a weak reference to the Method* so if
1721 // it's being unloaded there's no way to look it up since the weak
1722 // ref will have been cleared.
1723 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1724 assert(!unload_reported(), "already unloaded");
1725 JvmtiDeferredEvent event =
1726 JvmtiDeferredEvent::compiled_method_unload_event(this,
1727 _jmethod_id, insts_begin());
1728 if (SafepointSynchronize::is_at_safepoint()) {
1729 // Don't want to take the queueing lock. Add it as pending and
1730 // it will get enqueued later.
1731 JvmtiDeferredEventQueue::add_pending_event(event);
1732 } else {
1733 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1734 JvmtiDeferredEventQueue::enqueue(event);
1735 }
1736 }
1737
1738 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1739 // any time. As the nmethod is being unloaded now we mark it has
1740 // having the unload event reported - this will ensure that we don't
1741 // attempt to report the event in the unlikely scenario where the
1742 // event is enabled at the time the nmethod is made a zombie.
1743 set_unload_reported();
1744 }
1745
1746 void static clean_ic_if_metadata_is_dead(CompiledIC *ic, BoolObjectClosure *is_alive) {
1747 if (ic->is_icholder_call()) {
1748 // The only exception is compiledICHolder oops which may
1749 // yet be marked below. (We check this further below).
1750 CompiledICHolder* cichk_oop = ic->cached_icholder();
1751
1752 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1753 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1754 return;
1755 }
1756 } else {
1757 Metadata* ic_oop = ic->cached_metadata();
1758 if (ic_oop != NULL) {
1759 if (ic_oop->is_klass()) {
1760 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1761 return;
1762 }
1763 } else if (ic_oop->is_method()) {
1764 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1765 return;
1766 }
1767 } else {
1768 ShouldNotReachHere();
1769 }
1770 }
1771 }
1772
1773 ic->set_to_clean();
1774 }
1775
1776 // This is called at the end of the strong tracing/marking phase of a
1777 // GC to unload an nmethod if it contains otherwise unreachable
1778 // oops.
1779
1780 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1781 // Make sure the oop's ready to receive visitors
1782 assert(!is_zombie() && !is_unloaded(),
1783 "should not call follow on zombie or unloaded nmethod");
1784
1785 // If the method is not entrant then a JMP is plastered over the
1786 // first few bytes. If an oop in the old code was there, that oop
1787 // should not get GC'd. Skip the first few bytes of oops on
1788 // not-entrant methods.
1789 address low_boundary = verified_entry_point();
1790 if (is_not_entrant()) {
1791 low_boundary += NativeJump::instruction_size;
1792 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1793 // (See comment above.)
1794 }
1795
1796 // The RedefineClasses() API can cause the class unloading invariant
1797 // to no longer be true. See jvmtiExport.hpp for details.
1798 // Also, leave a debugging breadcrumb in local flag.
1799 if (JvmtiExport::has_redefined_a_class()) {
1800 // This set of the unloading_occurred flag is done before the
1801 // call to post_compiled_method_unload() so that the unloading
1802 // of this nmethod is reported.
1803 unloading_occurred = true;
1804 }
1805
1806 // Exception cache
1807 clean_exception_cache(is_alive);
1808
1809 // If class unloading occurred we first iterate over all inline caches and
1810 // clear ICs where the cached oop is referring to an unloaded klass or method.
1811 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1812 // iteration below.
1813 if (unloading_occurred) {
1814 RelocIterator iter(this, low_boundary);
1815 while(iter.next()) {
1816 if (iter.type() == relocInfo::virtual_call_type) {
1817 CompiledIC *ic = CompiledIC_at(&iter);
1818 clean_ic_if_metadata_is_dead(ic, is_alive);
1819 }
1820 }
1821 }
1822
1823 // Compiled code
1824 {
1825 RelocIterator iter(this, low_boundary);
1826 while (iter.next()) {
1827 if (iter.type() == relocInfo::oop_type) {
1828 oop_Relocation* r = iter.oop_reloc();
1829 // In this loop, we must only traverse those oops directly embedded in
1830 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1831 assert(1 == (r->oop_is_immediate()) +
1832 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1833 "oop must be found in exactly one place");
1834 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1835 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1836 return;
1837 }
1838 }
1839 }
1840 }
1841 }
1842
1843
1844 // Scopes
1845 for (oop* p = oops_begin(); p < oops_end(); p++) {
1846 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1847 if (can_unload(is_alive, p, unloading_occurred)) {
1848 return;
1849 }
1850 }
1851
1852 #if INCLUDE_JVMCI
1853 // Follow JVMCI method
1854 BarrierSet* bs = Universe::heap()->barrier_set();
1855 if (_jvmci_installed_code != NULL) {
1856 if (_jvmci_installed_code->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(_jvmci_installed_code)) {
1857 if (!is_alive->do_object_b(_jvmci_installed_code)) {
1858 clear_jvmci_installed_code();
1859 }
1860 } else {
1861 if (can_unload(is_alive, (oop*)&_jvmci_installed_code, unloading_occurred)) {
1862 return;
1863 }
1864 }
1865 }
1866
1867 if (_speculation_log != NULL) {
1868 if (!is_alive->do_object_b(_speculation_log)) {
1869 bs->write_ref_nmethod_pre(&_speculation_log, this);
1870 _speculation_log = NULL;
1871 bs->write_ref_nmethod_post(&_speculation_log, this);
1872 }
1873 }
1874 #endif
1875
1876
1877 // Ensure that all metadata is still alive
1878 verify_metadata_loaders(low_boundary, is_alive);
1879 }
1880
1881 template <class CompiledICorStaticCall>
1882 static bool clean_if_nmethod_is_unloaded(CompiledICorStaticCall *ic, address addr, BoolObjectClosure *is_alive, nmethod* from) {
1883 // Ok, to lookup references to zombies here
1884 CodeBlob *cb = CodeCache::find_blob_unsafe(addr);
1885 if (cb != NULL && cb->is_nmethod()) {
1886 nmethod* nm = (nmethod*)cb;
1887
1888 if (nm->unloading_clock() != nmethod::global_unloading_clock()) {
1889 // The nmethod has not been processed yet.
1890 return true;
1891 }
1892
1893 // Clean inline caches pointing to both zombie and not_entrant methods
1894 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1895 ic->set_to_clean();
1896 assert(ic->is_clean(), "nmethod " PTR_FORMAT "not clean %s", p2i(from), from->method()->name_and_sig_as_C_string());
1897 }
1898 }
1899
1900 return false;
1901 }
1902
1903 static bool clean_if_nmethod_is_unloaded(CompiledIC *ic, BoolObjectClosure *is_alive, nmethod* from) {
1904 return clean_if_nmethod_is_unloaded(ic, ic->ic_destination(), is_alive, from);
1905 }
1906
1907 static bool clean_if_nmethod_is_unloaded(CompiledStaticCall *csc, BoolObjectClosure *is_alive, nmethod* from) {
1908 return clean_if_nmethod_is_unloaded(csc, csc->destination(), is_alive, from);
1909 }
1910
1911 bool nmethod::unload_if_dead_at(RelocIterator* iter_at_oop, BoolObjectClosure *is_alive, bool unloading_occurred) {
1912 assert(iter_at_oop->type() == relocInfo::oop_type, "Wrong relocation type");
1913
1914 oop_Relocation* r = iter_at_oop->oop_reloc();
1915 // Traverse those oops directly embedded in the code.
1916 // Other oops (oop_index>0) are seen as part of scopes_oops.
1917 assert(1 == (r->oop_is_immediate()) +
1918 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1919 "oop must be found in exactly one place");
1920 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1921 // Unload this nmethod if the oop is dead.
1922 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1923 return true;;
1924 }
1925 }
1926
1927 return false;
1928 }
1929
1930
1931 bool nmethod::do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred) {
1932 ResourceMark rm;
1933
1934 // Make sure the oop's ready to receive visitors
1935 assert(!is_zombie() && !is_unloaded(),
1936 "should not call follow on zombie or unloaded nmethod");
1937
1938 // If the method is not entrant then a JMP is plastered over the
1939 // first few bytes. If an oop in the old code was there, that oop
1940 // should not get GC'd. Skip the first few bytes of oops on
1941 // not-entrant methods.
1942 address low_boundary = verified_entry_point();
1943 if (is_not_entrant()) {
1944 low_boundary += NativeJump::instruction_size;
1945 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1946 // (See comment above.)
1947 }
1948
1949 // The RedefineClasses() API can cause the class unloading invariant
1950 // to no longer be true. See jvmtiExport.hpp for details.
1951 // Also, leave a debugging breadcrumb in local flag.
1952 if (JvmtiExport::has_redefined_a_class()) {
1953 // This set of the unloading_occurred flag is done before the
1954 // call to post_compiled_method_unload() so that the unloading
1955 // of this nmethod is reported.
1956 unloading_occurred = true;
1957 }
1958
1959 // Exception cache
1960 clean_exception_cache(is_alive);
1961
1962 bool is_unloaded = false;
1963 bool postponed = false;
1964
1965 RelocIterator iter(this, low_boundary);
1966 while(iter.next()) {
1967
1968 switch (iter.type()) {
1969
1970 case relocInfo::virtual_call_type:
1971 if (unloading_occurred) {
1972 // If class unloading occurred we first iterate over all inline caches and
1973 // clear ICs where the cached oop is referring to an unloaded klass or method.
1974 clean_ic_if_metadata_is_dead(CompiledIC_at(&iter), is_alive);
1975 }
1976
1977 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1978 break;
1979
1980 case relocInfo::opt_virtual_call_type:
1981 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1982 break;
1983
1984 case relocInfo::static_call_type:
1985 postponed |= clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
1986 break;
1987
1988 case relocInfo::oop_type:
1989 if (!is_unloaded) {
1990 is_unloaded = unload_if_dead_at(&iter, is_alive, unloading_occurred);
1991 }
1992 break;
1993
1994 case relocInfo::metadata_type:
1995 break; // nothing to do.
1996 }
1997 }
1998
1999 if (is_unloaded) {
2000 return postponed;
2001 }
2002
2003 // Scopes
2004 for (oop* p = oops_begin(); p < oops_end(); p++) {
2005 if (*p == Universe::non_oop_word()) continue; // skip non-oops
2006 if (can_unload(is_alive, p, unloading_occurred)) {
2007 is_unloaded = true;
2008 break;
2009 }
2010 }
2011
2012 if (is_unloaded) {
2013 return postponed;
2014 }
2015
2016 #if INCLUDE_JVMCI
2017 // Follow JVMCI method
2018 BarrierSet* bs = Universe::heap()->barrier_set();
2019 if (_jvmci_installed_code != NULL) {
2020 if (_jvmci_installed_code->is_a(HotSpotNmethod::klass()) && HotSpotNmethod::isDefault(_jvmci_installed_code)) {
2021 if (!is_alive->do_object_b(_jvmci_installed_code)) {
2022 clear_jvmci_installed_code();
2023 }
2024 } else {
2025 if (can_unload(is_alive, (oop*)&_jvmci_installed_code, unloading_occurred)) {
2026 is_unloaded = true;
2027 }
2028 }
2029 }
2030
2031 if (_speculation_log != NULL) {
2032 if (!is_alive->do_object_b(_speculation_log)) {
2033 bs->write_ref_nmethod_pre(&_speculation_log, this);
2034 _speculation_log = NULL;
2035 bs->write_ref_nmethod_post(&_speculation_log, this);
2036 }
2037 }
2038 #endif
2039
2040 // Ensure that all metadata is still alive
2041 verify_metadata_loaders(low_boundary, is_alive);
2042
2043 return postponed;
2044 }
2045
2046 void nmethod::do_unloading_parallel_postponed(BoolObjectClosure* is_alive, bool unloading_occurred) {
2047 ResourceMark rm;
2048
2049 // Make sure the oop's ready to receive visitors
2050 assert(!is_zombie(),
2051 "should not call follow on zombie nmethod");
2052
2053 // If the method is not entrant then a JMP is plastered over the
2054 // first few bytes. If an oop in the old code was there, that oop
2055 // should not get GC'd. Skip the first few bytes of oops on
2056 // not-entrant methods.
2057 address low_boundary = verified_entry_point();
2058 if (is_not_entrant()) {
2059 low_boundary += NativeJump::instruction_size;
2060 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
2061 // (See comment above.)
2062 }
2063
2064 RelocIterator iter(this, low_boundary);
2065 while(iter.next()) {
2066
2067 switch (iter.type()) {
2068
2069 case relocInfo::virtual_call_type:
2070 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
2071 break;
2072
2073 case relocInfo::opt_virtual_call_type:
2074 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
2075 break;
2076
2077 case relocInfo::static_call_type:
2078 clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
2079 break;
2080 }
2081 }
2082 }
2083
2084 #ifdef ASSERT
2085
2086 class CheckClass : AllStatic {
2087 static BoolObjectClosure* _is_alive;
2088
2089 // Check class_loader is alive for this bit of metadata.
2090 static void check_class(Metadata* md) {
2091 Klass* klass = NULL;
2092 if (md->is_klass()) {
2093 klass = ((Klass*)md);
2094 } else if (md->is_method()) {
2095 klass = ((Method*)md)->method_holder();
2096 } else if (md->is_methodData()) {
2097 klass = ((MethodData*)md)->method()->method_holder();
2098 } else {
2099 md->print();
2100 ShouldNotReachHere();
2101 }
2102 assert(klass->is_loader_alive(_is_alive), "must be alive");
2103 }
2104 public:
2105 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
2106 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
2107 _is_alive = is_alive;
2108 nm->metadata_do(check_class);
2109 }
2110 };
2111
2112 // This is called during a safepoint so can use static data
2113 BoolObjectClosure* CheckClass::_is_alive = NULL;
2114 #endif // ASSERT
2115
2116
2117 // Processing of oop references should have been sufficient to keep
2118 // all strong references alive. Any weak references should have been
2119 // cleared as well. Visit all the metadata and ensure that it's
2120 // really alive.
2121 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
2122 #ifdef ASSERT
2123 RelocIterator iter(this, low_boundary);
2124 while (iter.next()) {
2125 // static_stub_Relocations may have dangling references to
2126 // Method*s so trim them out here. Otherwise it looks like
2127 // compiled code is maintaining a link to dead metadata.
2128 address static_call_addr = NULL;
2129 if (iter.type() == relocInfo::opt_virtual_call_type) {
2130 CompiledIC* cic = CompiledIC_at(&iter);
2131 if (!cic->is_call_to_interpreted()) {
2132 static_call_addr = iter.addr();
2133 }
2134 } else if (iter.type() == relocInfo::static_call_type) {
2135 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
2136 if (!csc->is_call_to_interpreted()) {
2137 static_call_addr = iter.addr();
2138 }
2139 }
2140 if (static_call_addr != NULL) {
2141 RelocIterator sciter(this, low_boundary);
2142 while (sciter.next()) {
2143 if (sciter.type() == relocInfo::static_stub_type &&
2144 sciter.static_stub_reloc()->static_call() == static_call_addr) {
2145 sciter.static_stub_reloc()->clear_inline_cache();
2146 }
2147 }
2148 }
2149 }
2150 // Check that the metadata embedded in the nmethod is alive
2151 CheckClass::do_check_class(is_alive, this);
2152 #endif
2153 }
2154
2155
2156 // Iterate over metadata calling this function. Used by RedefineClasses
2157 void nmethod::metadata_do(void f(Metadata*)) {
2158 address low_boundary = verified_entry_point();
2159 if (is_not_entrant()) {
2160 low_boundary += NativeJump::instruction_size;
2161 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
2162 // (See comment above.)
2163 }
2164 {
2165 // Visit all immediate references that are embedded in the instruction stream.
2166 RelocIterator iter(this, low_boundary);
2167 while (iter.next()) {
2168 if (iter.type() == relocInfo::metadata_type ) {
2169 metadata_Relocation* r = iter.metadata_reloc();
2170 // In this metadata, we must only follow those metadatas directly embedded in
2171 // the code. Other metadatas (oop_index>0) are seen as part of
2172 // the metadata section below.
2173 assert(1 == (r->metadata_is_immediate()) +
2174 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
2175 "metadata must be found in exactly one place");
2176 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
2177 Metadata* md = r->metadata_value();
2178 if (md != _method) f(md);
2179 }
2180 } else if (iter.type() == relocInfo::virtual_call_type) {
2181 // Check compiledIC holders associated with this nmethod
2182 CompiledIC *ic = CompiledIC_at(&iter);
2183 if (ic->is_icholder_call()) {
2184 CompiledICHolder* cichk = ic->cached_icholder();
2185 f(cichk->holder_method());
2186 f(cichk->holder_klass());
2187 } else {
2188 Metadata* ic_oop = ic->cached_metadata();
2189 if (ic_oop != NULL) {
2190 f(ic_oop);
2191 }
2192 }
2193 }
2194 }
2195 }
2196
2197 // Visit the metadata section
2198 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
2199 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
2200 Metadata* md = *p;
2201 f(md);
2202 }
2203
2204 // Visit metadata not embedded in the other places.
2205 if (_method != NULL) f(_method);
2206 }
2207
2208 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
2209 // make sure the oops ready to receive visitors
2210 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
2211 assert(!is_unloaded(), "should not call follow on unloaded nmethod");
2212
2213 // If the method is not entrant or zombie then a JMP is plastered over the
2214 // first few bytes. If an oop in the old code was there, that oop
2215 // should not get GC'd. Skip the first few bytes of oops on
2216 // not-entrant methods.
2217 address low_boundary = verified_entry_point();
2218 if (is_not_entrant()) {
2219 low_boundary += NativeJump::instruction_size;
2220 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
2221 // (See comment above.)
2222 }
2223
2224 #if INCLUDE_JVMCI
2225 if (_jvmci_installed_code != NULL) {
2226 f->do_oop((oop*) &_jvmci_installed_code);
2227 }
2228 if (_speculation_log != NULL) {
2229 f->do_oop((oop*) &_speculation_log);
2230 }
2231 #endif
2232
2233 RelocIterator iter(this, low_boundary);
2234
2235 while (iter.next()) {
2236 if (iter.type() == relocInfo::oop_type ) {
2237 oop_Relocation* r = iter.oop_reloc();
2238 // In this loop, we must only follow those oops directly embedded in
2239 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
2240 assert(1 == (r->oop_is_immediate()) +
2241 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
2242 "oop must be found in exactly one place");
2243 if (r->oop_is_immediate() && r->oop_value() != NULL) {
2244 f->do_oop(r->oop_addr());
2245 }
2246 }
2247 }
2248
2249 // Scopes
2250 // This includes oop constants not inlined in the code stream.
2251 for (oop* p = oops_begin(); p < oops_end(); p++) {
2252 if (*p == Universe::non_oop_word()) continue; // skip non-oops
2253 f->do_oop(p);
2254 }
2255 }
2256
2257 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
2258
2259 nmethod* volatile nmethod::_oops_do_mark_nmethods;
2260
2261 // An nmethod is "marked" if its _mark_link is set non-null.
2262 // Even if it is the end of the linked list, it will have a non-null link value,
2263 // as long as it is on the list.
2264 // This code must be MP safe, because it is used from parallel GC passes.
2265 bool nmethod::test_set_oops_do_mark() {
2266 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
2267 nmethod* observed_mark_link = _oops_do_mark_link;
2268 if (observed_mark_link == NULL) {
2269 // Claim this nmethod for this thread to mark.
2270 observed_mark_link = (nmethod*)
2271 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
2272 if (observed_mark_link == NULL) {
2273
2274 // Atomically append this nmethod (now claimed) to the head of the list:
2275 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
2276 for (;;) {
2277 nmethod* required_mark_nmethods = observed_mark_nmethods;
2278 _oops_do_mark_link = required_mark_nmethods;
2279 observed_mark_nmethods = (nmethod*)
2280 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
2281 if (observed_mark_nmethods == required_mark_nmethods)
2282 break;
2283 }
2284 // Mark was clear when we first saw this guy.
2285 if (TraceScavenge) { print_on(tty, "oops_do, mark"); }
2286 return false;
2287 }
2288 }
2289 // On fall through, another racing thread marked this nmethod before we did.
2290 return true;
2291 }
2292
2293 void nmethod::oops_do_marking_prologue() {
2294 if (TraceScavenge) { tty->print_cr("[oops_do_marking_prologue"); }
2295 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
2296 // We use cmpxchg_ptr instead of regular assignment here because the user
2297 // may fork a bunch of threads, and we need them all to see the same state.
2298 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
2299 guarantee(observed == NULL, "no races in this sequential code");
2300 }
2301
2302 void nmethod::oops_do_marking_epilogue() {
2303 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
2304 nmethod* cur = _oops_do_mark_nmethods;
2305 while (cur != NMETHOD_SENTINEL) {
2306 assert(cur != NULL, "not NULL-terminated");
2307 nmethod* next = cur->_oops_do_mark_link;
2308 cur->_oops_do_mark_link = NULL;
2309 DEBUG_ONLY(cur->verify_oop_relocations());
2310 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
2311 cur = next;
2312 }
2313 void* required = _oops_do_mark_nmethods;
2314 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
2315 guarantee(observed == required, "no races in this sequential code");
2316 if (TraceScavenge) { tty->print_cr("oops_do_marking_epilogue]"); }
2317 }
2318
2319 class DetectScavengeRoot: public OopClosure {
2320 bool _detected_scavenge_root;
2321 public:
2322 DetectScavengeRoot() : _detected_scavenge_root(false)
2323 { NOT_PRODUCT(_print_nm = NULL); }
2324 bool detected_scavenge_root() { return _detected_scavenge_root; }
2325 virtual void do_oop(oop* p) {
2326 if ((*p) != NULL && (*p)->is_scavengable()) {
2327 NOT_PRODUCT(maybe_print(p));
2328 _detected_scavenge_root = true;
2329 }
2330 }
2331 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2332
2333 #ifndef PRODUCT
2334 nmethod* _print_nm;
2335 void maybe_print(oop* p) {
2336 if (_print_nm == NULL) return;
2337 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
2338 tty->print_cr("" PTR_FORMAT "[offset=%d] detected scavengable oop " PTR_FORMAT " (found at " PTR_FORMAT ")",
2339 p2i(_print_nm), (int)((intptr_t)p - (intptr_t)_print_nm),
2340 p2i(*p), p2i(p));
2341 (*p)->print();
2342 }
2343 #endif //PRODUCT
2344 };
2345
2346 bool nmethod::detect_scavenge_root_oops() {
2347 DetectScavengeRoot detect_scavenge_root;
2348 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
2349 oops_do(&detect_scavenge_root);
2350 return detect_scavenge_root.detected_scavenge_root();
2351 }
2352
2353 // Method that knows how to preserve outgoing arguments at call. This method must be
2354 // called with a frame corresponding to a Java invoke
2355 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
2356 #ifndef SHARK
2357 if (method() != NULL && !method()->is_native()) {
2358 address pc = fr.pc();
2359 SimpleScopeDesc ssd(this, pc);
2360 Bytecode_invoke call(ssd.method(), ssd.bci());
2361 bool has_receiver = call.has_receiver();
2362 bool has_appendix = call.has_appendix();
2363 Symbol* signature = call.signature();
2364
2365 // The method attached by JIT-compilers should be used, if present.
2366 // Bytecode can be inaccurate in such case.
2367 Method* callee = attached_method_before_pc(pc);
2368 if (callee != NULL) {
2369 has_receiver = !(callee->access_flags().is_static());
2370 has_appendix = false;
2371 signature = callee->signature();
2372 }
2373
2374 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
2375 }
2376 #endif // !SHARK
2377 }
2378
2379 inline bool includes(void* p, void* from, void* to) {
2380 return from <= p && p < to;
2381 }
2382
2383
2384 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2385 assert(count >= 2, "must be sentinel values, at least");
2386
2387 #ifdef ASSERT
2388 // must be sorted and unique; we do a binary search in find_pc_desc()
2389 int prev_offset = pcs[0].pc_offset();
2390 assert(prev_offset == PcDesc::lower_offset_limit,
2391 "must start with a sentinel");
2392 for (int i = 1; i < count; i++) {
2393 int this_offset = pcs[i].pc_offset();
2394 assert(this_offset > prev_offset, "offsets must be sorted");
2395 prev_offset = this_offset;
2396 }
2397 assert(prev_offset == PcDesc::upper_offset_limit,
2398 "must end with a sentinel");
2399 #endif //ASSERT
2400
2401 // Search for MethodHandle invokes and tag the nmethod.
2402 for (int i = 0; i < count; i++) {
2403 if (pcs[i].is_method_handle_invoke()) {
2404 set_has_method_handle_invokes(true);
2405 break;
2406 }
2407 }
2408 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2409
2410 int size = count * sizeof(PcDesc);
2411 assert(scopes_pcs_size() >= size, "oob");
2412 memcpy(scopes_pcs_begin(), pcs, size);
2413
2414 // Adjust the final sentinel downward.
2415 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2416 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2417 last_pc->set_pc_offset(content_size() + 1);
2418 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2419 // Fill any rounding gaps with copies of the last record.
2420 last_pc[1] = last_pc[0];
2421 }
2422 // The following assert could fail if sizeof(PcDesc) is not
2423 // an integral multiple of oopSize (the rounding term).
2424 // If it fails, change the logic to always allocate a multiple
2425 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2426 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2427 }
2428
2429 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2430 assert(scopes_data_size() >= size, "oob");
2431 memcpy(scopes_data_begin(), buffer, size);
2432 }
2433
2434 // When using JVMCI the address might be off by the size of a call instruction.
2435 bool nmethod::is_deopt_entry(address pc) {
2436 return pc == deopt_handler_begin()
2437 #if INCLUDE_JVMCI
2438 || pc == (deopt_handler_begin() + NativeCall::instruction_size)
2439 #endif
2440 ;
2441 }
2442
2443 #ifdef ASSERT
2444 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2445 PcDesc* lower = nm->scopes_pcs_begin();
2446 PcDesc* upper = nm->scopes_pcs_end();
2447 lower += 1; // exclude initial sentinel
2448 PcDesc* res = NULL;
2449 for (PcDesc* p = lower; p < upper; p++) {
2450 NOT_PRODUCT(--pc_nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2451 if (match_desc(p, pc_offset, approximate)) {
2452 if (res == NULL)
2453 res = p;
2454 else
2455 res = (PcDesc*) badAddress;
2456 }
2457 }
2458 return res;
2459 }
2460 #endif
2461
2462
2463 // Finds a PcDesc with real-pc equal to "pc"
2464 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2465 address base_address = code_begin();
2466 if ((pc < base_address) ||
2467 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2468 return NULL; // PC is wildly out of range
2469 }
2470 int pc_offset = (int) (pc - base_address);
2471
2472 // Check the PcDesc cache if it contains the desired PcDesc
2473 // (This as an almost 100% hit rate.)
2474 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2475 if (res != NULL) {
2476 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2477 return res;
2478 }
2479
2480 // Fallback algorithm: quasi-linear search for the PcDesc
2481 // Find the last pc_offset less than the given offset.
2482 // The successor must be the required match, if there is a match at all.
2483 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2484 PcDesc* lower = scopes_pcs_begin();
2485 PcDesc* upper = scopes_pcs_end();
2486 upper -= 1; // exclude final sentinel
2487 if (lower >= upper) return NULL; // native method; no PcDescs at all
2488
2489 #define assert_LU_OK \
2490 /* invariant on lower..upper during the following search: */ \
2491 assert(lower->pc_offset() < pc_offset, "sanity"); \
2492 assert(upper->pc_offset() >= pc_offset, "sanity")
2493 assert_LU_OK;
2494
2495 // Use the last successful return as a split point.
2496 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2497 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2498 if (mid->pc_offset() < pc_offset) {
2499 lower = mid;
2500 } else {
2501 upper = mid;
2502 }
2503
2504 // Take giant steps at first (4096, then 256, then 16, then 1)
2505 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2506 const int RADIX = (1 << LOG2_RADIX);
2507 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2508 while ((mid = lower + step) < upper) {
2509 assert_LU_OK;
2510 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2511 if (mid->pc_offset() < pc_offset) {
2512 lower = mid;
2513 } else {
2514 upper = mid;
2515 break;
2516 }
2517 }
2518 assert_LU_OK;
2519 }
2520
2521 // Sneak up on the value with a linear search of length ~16.
2522 while (true) {
2523 assert_LU_OK;
2524 mid = lower + 1;
2525 NOT_PRODUCT(++pc_nmethod_stats.pc_desc_searches);
2526 if (mid->pc_offset() < pc_offset) {
2527 lower = mid;
2528 } else {
2529 upper = mid;
2530 break;
2531 }
2532 }
2533 #undef assert_LU_OK
2534
2535 if (match_desc(upper, pc_offset, approximate)) {
2536 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2537 _pc_desc_cache.add_pc_desc(upper);
2538 return upper;
2539 } else {
2540 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2541 return NULL;
2542 }
2543 }
2544
2545
2546 void nmethod::check_all_dependencies(DepChange& changes) {
2547 // Checked dependencies are allocated into this ResourceMark
2548 ResourceMark rm;
2549
2550 // Turn off dependency tracing while actually testing dependencies.
2551 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
2552
2553 typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
2554 &DependencySignature::equals, 11027> DepTable;
2555
2556 DepTable* table = new DepTable();
2557
2558 // Iterate over live nmethods and check dependencies of all nmethods that are not
2559 // marked for deoptimization. A particular dependency is only checked once.
2560 NMethodIterator iter;
2561 while(iter.next()) {
2562 nmethod* nm = iter.method();
2563 // Only notify for live nmethods
2564 if (nm->is_alive() && !nm->is_marked_for_deoptimization()) {
2565 for (Dependencies::DepStream deps(nm); deps.next(); ) {
2566 // Construct abstraction of a dependency.
2567 DependencySignature* current_sig = new DependencySignature(deps);
2568
2569 // Determine if dependency is already checked. table->put(...) returns
2570 // 'true' if the dependency is added (i.e., was not in the hashtable).
2571 if (table->put(*current_sig, 1)) {
2572 if (deps.check_dependency() != NULL) {
2573 // Dependency checking failed. Print out information about the failed
2574 // dependency and finally fail with an assert. We can fail here, since
2575 // dependency checking is never done in a product build.
2576 tty->print_cr("Failed dependency:");
2577 changes.print();
2578 nm->print();
2579 nm->print_dependencies();
2580 assert(false, "Should have been marked for deoptimization");
2581 }
2582 }
2583 }
2584 }
2585 }
2586 }
2587
2588 bool nmethod::check_dependency_on(DepChange& changes) {
2589 // What has happened:
2590 // 1) a new class dependee has been added
2591 // 2) dependee and all its super classes have been marked
2592 bool found_check = false; // set true if we are upset
2593 for (Dependencies::DepStream deps(this); deps.next(); ) {
2594 // Evaluate only relevant dependencies.
2595 if (deps.spot_check_dependency_at(changes) != NULL) {
2596 found_check = true;
2597 NOT_DEBUG(break);
2598 }
2599 }
2600 return found_check;
2601 }
2602
2603 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2604 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2605 Array<Method*>* dependee_methods = dependee_ik->methods();
2606 for (Dependencies::DepStream deps(this); deps.next(); ) {
2607 if (deps.type() == Dependencies::evol_method) {
2608 Method* method = deps.method_argument(0);
2609 for (int j = 0; j < dependee_methods->length(); j++) {
2610 if (dependee_methods->at(j) == method) {
2611 // RC_TRACE macro has an embedded ResourceMark
2612 RC_TRACE(0x01000000,
2613 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2614 _method->method_holder()->external_name(),
2615 _method->name()->as_C_string(),
2616 _method->signature()->as_C_string(), compile_id(),
2617 method->method_holder()->external_name(),
2618 method->name()->as_C_string(),
2619 method->signature()->as_C_string()));
2620 if (TraceDependencies || LogCompilation)
2621 deps.log_dependency(dependee);
2622 return true;
2623 }
2624 }
2625 }
2626 }
2627 return false;
2628 }
2629
2630 // Called from mark_for_deoptimization, when dependee is invalidated.
2631 bool nmethod::is_dependent_on_method(Method* dependee) {
2632 for (Dependencies::DepStream deps(this); deps.next(); ) {
2633 if (deps.type() != Dependencies::evol_method)
2634 continue;
2635 Method* method = deps.method_argument(0);
2636 if (method == dependee) return true;
2637 }
2638 return false;
2639 }
2640
2641
2642 bool nmethod::is_patchable_at(address instr_addr) {
2643 assert(insts_contains(instr_addr), "wrong nmethod used");
2644 if (is_zombie()) {
2645 // a zombie may never be patched
2646 return false;
2647 }
2648 return true;
2649 }
2650
2651
2652 address nmethod::continuation_for_implicit_exception(address pc) {
2653 // Exception happened outside inline-cache check code => we are inside
2654 // an active nmethod => use cpc to determine a return address
2655 int exception_offset = pc - code_begin();
2656 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2657 #ifdef ASSERT
2658 if (cont_offset == 0) {
2659 Thread* thread = Thread::current();
2660 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2661 HandleMark hm(thread);
2662 ResourceMark rm(thread);
2663 CodeBlob* cb = CodeCache::find_blob(pc);
2664 assert(cb != NULL && cb == this, "");
2665 ttyLocker ttyl;
2666 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, p2i(pc));
2667 print();
2668 method()->print_codes();
2669 print_code();
2670 print_pcs();
2671 }
2672 #endif
2673 if (cont_offset == 0) {
2674 // Let the normal error handling report the exception
2675 return NULL;
2676 }
2677 return code_begin() + cont_offset;
2678 }
2679
2680
2681
2682 void nmethod_init() {
2683 // make sure you didn't forget to adjust the filler fields
2684 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2685 }
2686
2687
2688 //-------------------------------------------------------------------------------------------
2689
2690
2691 // QQQ might we make this work from a frame??
2692 nmethodLocker::nmethodLocker(address pc) {
2693 CodeBlob* cb = CodeCache::find_blob(pc);
2694 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2695 _nm = (nmethod*)cb;
2696 lock_nmethod(_nm);
2697 }
2698
2699 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2700 // should pass zombie_ok == true.
2701 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2702 if (nm == NULL) return;
2703 Atomic::inc(&nm->_lock_count);
2704 assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2705 }
2706
2707 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2708 if (nm == NULL) return;
2709 Atomic::dec(&nm->_lock_count);
2710 assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2711 }
2712
2713 // -----------------------------------------------------------------------------
2714 // nmethod::get_deopt_original_pc
2715 //
2716 // Return the original PC for the given PC if:
2717 // (a) the given PC belongs to a nmethod and
2718 // (b) it is a deopt PC
2719 address nmethod::get_deopt_original_pc(const frame* fr) {
2720 if (fr->cb() == NULL) return NULL;
2721
2722 nmethod* nm = fr->cb()->as_nmethod_or_null();
2723 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2724 return nm->get_original_pc(fr);
2725
2726 return NULL;
2727 }
2728
2729
2730 // -----------------------------------------------------------------------------
2731 // MethodHandle
2732
2733 bool nmethod::is_method_handle_return(address return_pc) {
2734 if (!has_method_handle_invokes()) return false;
2735 PcDesc* pd = pc_desc_at(return_pc);
2736 if (pd == NULL)
2737 return false;
2738 return pd->is_method_handle_invoke();
2739 }
2740
2741
2742 // -----------------------------------------------------------------------------
2743 // Verification
2744
2745 class VerifyOopsClosure: public OopClosure {
2746 nmethod* _nm;
2747 bool _ok;
2748 public:
2749 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2750 bool ok() { return _ok; }
2751 virtual void do_oop(oop* p) {
2752 if ((*p) == NULL || (*p)->is_oop()) return;
2753 if (_ok) {
2754 _nm->print_nmethod(true);
2755 _ok = false;
2756 }
2757 tty->print_cr("*** non-oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2758 p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2759 }
2760 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2761 };
2762
2763 void nmethod::verify() {
2764
2765 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2766 // seems odd.
2767
2768 if (is_zombie() || is_not_entrant() || is_unloaded())
2769 return;
2770
2771 // Make sure all the entry points are correctly aligned for patching.
2772 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2773
2774 // assert(method()->is_oop(), "must be valid");
2775
2776 ResourceMark rm;
2777
2778 if (!CodeCache::contains(this)) {
2779 fatal("nmethod at " INTPTR_FORMAT " not in zone", p2i(this));
2780 }
2781
2782 if(is_native_method() )
2783 return;
2784
2785 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2786 if (nm != this) {
2787 fatal("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", p2i(this));
2788 }
2789
2790 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2791 if (! p->verify(this)) {
2792 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", p2i(this));
2793 }
2794 }
2795
2796 VerifyOopsClosure voc(this);
2797 oops_do(&voc);
2798 assert(voc.ok(), "embedded oops must be OK");
2799 verify_scavenge_root_oops();
2800
2801 verify_scopes();
2802 }
2803
2804
2805 void nmethod::verify_interrupt_point(address call_site) {
2806 // Verify IC only when nmethod installation is finished.
2807 bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed
2808 || !this->is_in_use(); // nmethod is installed, but not in 'in_use' state
2809 if (is_installed) {
2810 Thread *cur = Thread::current();
2811 if (CompiledIC_lock->owner() == cur ||
2812 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2813 SafepointSynchronize::is_at_safepoint())) {
2814 CompiledIC_at(this, call_site);
2815 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2816 } else {
2817 MutexLocker ml_verify (CompiledIC_lock);
2818 CompiledIC_at(this, call_site);
2819 }
2820 }
2821
2822 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2823 assert(pd != NULL, "PcDesc must exist");
2824 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2825 pd->obj_decode_offset(), pd->should_reexecute(), pd->rethrow_exception(),
2826 pd->return_oop());
2827 !sd->is_top(); sd = sd->sender()) {
2828 sd->verify();
2829 }
2830 }
2831
2832 void nmethod::verify_scopes() {
2833 if( !method() ) return; // Runtime stubs have no scope
2834 if (method()->is_native()) return; // Ignore stub methods.
2835 // iterate through all interrupt point
2836 // and verify the debug information is valid.
2837 RelocIterator iter((nmethod*)this);
2838 while (iter.next()) {
2839 address stub = NULL;
2840 switch (iter.type()) {
2841 case relocInfo::virtual_call_type:
2842 verify_interrupt_point(iter.addr());
2843 break;
2844 case relocInfo::opt_virtual_call_type:
2845 stub = iter.opt_virtual_call_reloc()->static_stub();
2846 verify_interrupt_point(iter.addr());
2847 break;
2848 case relocInfo::static_call_type:
2849 stub = iter.static_call_reloc()->static_stub();
2850 //verify_interrupt_point(iter.addr());
2851 break;
2852 case relocInfo::runtime_call_type:
2853 address destination = iter.reloc()->value();
2854 // Right now there is no way to find out which entries support
2855 // an interrupt point. It would be nice if we had this
2856 // information in a table.
2857 break;
2858 }
2859 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2860 }
2861 }
2862
2863
2864 // -----------------------------------------------------------------------------
2865 // Non-product code
2866 #ifndef PRODUCT
2867
2868 class DebugScavengeRoot: public OopClosure {
2869 nmethod* _nm;
2870 bool _ok;
2871 public:
2872 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2873 bool ok() { return _ok; }
2874 virtual void do_oop(oop* p) {
2875 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2876 if (_ok) {
2877 _nm->print_nmethod(true);
2878 _ok = false;
2879 }
2880 tty->print_cr("*** scavengable oop " PTR_FORMAT " found at " PTR_FORMAT " (offset %d)",
2881 p2i(*p), p2i(p), (int)((intptr_t)p - (intptr_t)_nm));
2882 (*p)->print();
2883 }
2884 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2885 };
2886
2887 void nmethod::verify_scavenge_root_oops() {
2888 if (UseG1GC) {
2889 return;
2890 }
2891
2892 if (!on_scavenge_root_list()) {
2893 // Actually look inside, to verify the claim that it's clean.
2894 DebugScavengeRoot debug_scavenge_root(this);
2895 oops_do(&debug_scavenge_root);
2896 if (!debug_scavenge_root.ok())
2897 fatal("found an unadvertised bad scavengable oop in the code cache");
2898 }
2899 assert(scavenge_root_not_marked(), "");
2900 }
2901
2902 #endif // PRODUCT
2903
2904 // Printing operations
2905
2906 void nmethod::print() const {
2907 ResourceMark rm;
2908 ttyLocker ttyl; // keep the following output all in one block
2909
2910 tty->print("Compiled method ");
2911
2912 if (is_compiled_by_c1()) {
2913 tty->print("(c1) ");
2914 } else if (is_compiled_by_c2()) {
2915 tty->print("(c2) ");
2916 } else if (is_compiled_by_shark()) {
2917 tty->print("(shark) ");
2918 } else if (is_compiled_by_jvmci()) {
2919 tty->print("(JVMCI) ");
2920 } else {
2921 tty->print("(nm) ");
2922 }
2923
2924 print_on(tty, NULL);
2925
2926 if (WizardMode) {
2927 tty->print("((nmethod*) " INTPTR_FORMAT ") ", p2i(this));
2928 tty->print(" for method " INTPTR_FORMAT , p2i(method()));
2929 tty->print(" { ");
2930 tty->print_cr("%s ", state());
2931 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2932 tty->print_cr("}:");
2933 }
2934 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2935 p2i(this),
2936 p2i(this) + size(),
2937 size());
2938 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2939 p2i(relocation_begin()),
2940 p2i(relocation_end()),
2941 relocation_size());
2942 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2943 p2i(consts_begin()),
2944 p2i(consts_end()),
2945 consts_size());
2946 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2947 p2i(insts_begin()),
2948 p2i(insts_end()),
2949 insts_size());
2950 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2951 p2i(stub_begin()),
2952 p2i(stub_end()),
2953 stub_size());
2954 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2955 p2i(oops_begin()),
2956 p2i(oops_end()),
2957 oops_size());
2958 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2959 p2i(metadata_begin()),
2960 p2i(metadata_end()),
2961 metadata_size());
2962 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2963 p2i(scopes_data_begin()),
2964 p2i(scopes_data_end()),
2965 scopes_data_size());
2966 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2967 p2i(scopes_pcs_begin()),
2968 p2i(scopes_pcs_end()),
2969 scopes_pcs_size());
2970 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2971 p2i(dependencies_begin()),
2972 p2i(dependencies_end()),
2973 dependencies_size());
2974 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2975 p2i(handler_table_begin()),
2976 p2i(handler_table_end()),
2977 handler_table_size());
2978 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2979 p2i(nul_chk_table_begin()),
2980 p2i(nul_chk_table_end()),
2981 nul_chk_table_size());
2982 }
2983
2984 #ifndef PRODUCT
2985
2986 void nmethod::print_scopes() {
2987 // Find the first pc desc for all scopes in the code and print it.
2988 ResourceMark rm;
2989 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2990 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2991 continue;
2992
2993 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2994 while (sd != NULL) {
2995 sd->print_on(tty, p);
2996 sd = sd->sender();
2997 }
2998 }
2999 }
3000
3001 void nmethod::print_dependencies() {
3002 ResourceMark rm;
3003 ttyLocker ttyl; // keep the following output all in one block
3004 tty->print_cr("Dependencies:");
3005 for (Dependencies::DepStream deps(this); deps.next(); ) {
3006 deps.print_dependency();
3007 Klass* ctxk = deps.context_type();
3008 if (ctxk != NULL) {
3009 if (ctxk->is_instance_klass() && InstanceKlass::cast(ctxk)->is_dependent_nmethod(this)) {
3010 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
3011 }
3012 }
3013 deps.log_dependency(); // put it into the xml log also
3014 }
3015 }
3016
3017
3018 void nmethod::print_relocations() {
3019 ResourceMark m; // in case methods get printed via the debugger
3020 tty->print_cr("relocations:");
3021 RelocIterator iter(this);
3022 iter.print();
3023 if (UseRelocIndex) {
3024 jint* index_end = (jint*)relocation_end() - 1;
3025 jint index_size = *index_end;
3026 jint* index_start = (jint*)( (address)index_end - index_size );
3027 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", p2i(index_start), index_size);
3028 if (index_size > 0) {
3029 jint* ip;
3030 for (ip = index_start; ip+2 <= index_end; ip += 2)
3031 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
3032 ip[0],
3033 ip[1],
3034 p2i(header_end()+ip[0]),
3035 p2i(relocation_begin()-1+ip[1]));
3036 for (; ip < index_end; ip++)
3037 tty->print_cr(" (%d ?)", ip[0]);
3038 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", p2i(ip), *ip);
3039 ip++;
3040 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", p2i(ip));
3041 }
3042 }
3043 }
3044
3045
3046 void nmethod::print_pcs() {
3047 ResourceMark m; // in case methods get printed via debugger
3048 tty->print_cr("pc-bytecode offsets:");
3049 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
3050 p->print(this);
3051 }
3052 }
3053
3054 void nmethod::print_recorded_oops() {
3055 tty->print_cr("Recorded oops:");
3056 for (int i = 0; i < oops_count(); i++) {
3057 oop o = oop_at(i);
3058 tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(o));
3059 if (o == (oop)Universe::non_oop_word()) {
3060 tty->print("non-oop word");
3061 } else {
3062 o->print_value();
3063 }
3064 tty->cr();
3065 }
3066 }
3067
3068 void nmethod::print_recorded_metadata() {
3069 tty->print_cr("Recorded metadata:");
3070 for (int i = 0; i < metadata_count(); i++) {
3071 Metadata* m = metadata_at(i);
3072 tty->print("#%3d: " INTPTR_FORMAT " ", i, p2i(m));
3073 if (m == (Metadata*)Universe::non_oop_word()) {
3074 tty->print("non-metadata word");
3075 } else {
3076 m->print_value_on_maybe_null(tty);
3077 }
3078 tty->cr();
3079 }
3080 }
3081
3082 #endif // PRODUCT
3083
3084 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
3085 RelocIterator iter(this, begin, end);
3086 bool have_one = false;
3087 while (iter.next()) {
3088 have_one = true;
3089 switch (iter.type()) {
3090 case relocInfo::none: return "no_reloc";
3091 case relocInfo::oop_type: {
3092 stringStream st;
3093 oop_Relocation* r = iter.oop_reloc();
3094 oop obj = r->oop_value();
3095 st.print("oop(");
3096 if (obj == NULL) st.print("NULL");
3097 else obj->print_value_on(&st);
3098 st.print(")");
3099 return st.as_string();
3100 }
3101 case relocInfo::metadata_type: {
3102 stringStream st;
3103 metadata_Relocation* r = iter.metadata_reloc();
3104 Metadata* obj = r->metadata_value();
3105 st.print("metadata(");
3106 if (obj == NULL) st.print("NULL");
3107 else obj->print_value_on(&st);
3108 st.print(")");
3109 return st.as_string();
3110 }
3111 case relocInfo::runtime_call_type: {
3112 stringStream st;
3113 st.print("runtime_call");
3114 runtime_call_Relocation* r = iter.runtime_call_reloc();
3115 address dest = r->destination();
3116 CodeBlob* cb = CodeCache::find_blob(dest);
3117 if (cb != NULL) {
3118 st.print(" %s", cb->name());
3119 } else {
3120 ResourceMark rm;
3121 const int buflen = 1024;
3122 char* buf = NEW_RESOURCE_ARRAY(char, buflen);
3123 int offset;
3124 if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
3125 st.print(" %s", buf);
3126 if (offset != 0) {
3127 st.print("+%d", offset);
3128 }
3129 }
3130 }
3131 return st.as_string();
3132 }
3133 case relocInfo::virtual_call_type: {
3134 stringStream st;
3135 st.print_raw("virtual_call");
3136 virtual_call_Relocation* r = iter.virtual_call_reloc();
3137 Method* m = r->method_value();
3138 if (m != NULL) {
3139 assert(m->is_method(), "");
3140 m->print_short_name(&st);
3141 }
3142 return st.as_string();
3143 }
3144 case relocInfo::opt_virtual_call_type: {
3145 stringStream st;
3146 st.print_raw("optimized virtual_call");
3147 opt_virtual_call_Relocation* r = iter.opt_virtual_call_reloc();
3148 Method* m = r->method_value();
3149 if (m != NULL) {
3150 assert(m->is_method(), "");
3151 m->print_short_name(&st);
3152 }
3153 return st.as_string();
3154 }
3155 case relocInfo::static_call_type: {
3156 stringStream st;
3157 st.print_raw("static_call");
3158 static_call_Relocation* r = iter.static_call_reloc();
3159 Method* m = r->method_value();
3160 if (m != NULL) {
3161 assert(m->is_method(), "");
3162 m->print_short_name(&st);
3163 }
3164 return st.as_string();
3165 }
3166 case relocInfo::static_stub_type: return "static_stub";
3167 case relocInfo::external_word_type: return "external_word";
3168 case relocInfo::internal_word_type: return "internal_word";
3169 case relocInfo::section_word_type: return "section_word";
3170 case relocInfo::poll_type: return "poll";
3171 case relocInfo::poll_return_type: return "poll_return";
3172 case relocInfo::type_mask: return "type_bit_mask";
3173 }
3174 }
3175 return have_one ? "other" : NULL;
3176 }
3177
3178 // Return a the last scope in (begin..end]
3179 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
3180 PcDesc* p = pc_desc_near(begin+1);
3181 if (p != NULL && p->real_pc(this) <= end) {
3182 return new ScopeDesc(this, p->scope_decode_offset(),
3183 p->obj_decode_offset(), p->should_reexecute(), p->rethrow_exception(),
3184 p->return_oop());
3185 }
3186 return NULL;
3187 }
3188
3189 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
3190 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
3191 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
3192 if (JVMCI_ONLY(_exception_offset >= 0 &&) block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
3193 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
3194 if (JVMCI_ONLY(_deoptimize_offset >= 0 &&) block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
3195
3196 if (has_method_handle_invokes())
3197 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
3198
3199 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
3200
3201 if (block_begin == entry_point()) {
3202 methodHandle m = method();
3203 if (m.not_null()) {
3204 stream->print(" # ");
3205 m->print_value_on(stream);
3206 stream->cr();
3207 }
3208 if (m.not_null() && !is_osr_method()) {
3209 ResourceMark rm;
3210 int sizeargs = m->size_of_parameters();
3211 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
3212 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
3213 {
3214 int sig_index = 0;
3215 if (!m->is_static())
3216 sig_bt[sig_index++] = T_OBJECT; // 'this'
3217 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
3218 BasicType t = ss.type();
3219 sig_bt[sig_index++] = t;
3220 if (type2size[t] == 2) {
3221 sig_bt[sig_index++] = T_VOID;
3222 } else {
3223 assert(type2size[t] == 1, "size is 1 or 2");
3224 }
3225 }
3226 assert(sig_index == sizeargs, "");
3227 }
3228 const char* spname = "sp"; // make arch-specific?
3229 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
3230 int stack_slot_offset = this->frame_size() * wordSize;
3231 int tab1 = 14, tab2 = 24;
3232 int sig_index = 0;
3233 int arg_index = (m->is_static() ? 0 : -1);
3234 bool did_old_sp = false;
3235 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
3236 bool at_this = (arg_index == -1);
3237 bool at_old_sp = false;
3238 BasicType t = (at_this ? T_OBJECT : ss.type());
3239 assert(t == sig_bt[sig_index], "sigs in sync");
3240 if (at_this)
3241 stream->print(" # this: ");
3242 else
3243 stream->print(" # parm%d: ", arg_index);
3244 stream->move_to(tab1);
3245 VMReg fst = regs[sig_index].first();
3246 VMReg snd = regs[sig_index].second();
3247 if (fst->is_reg()) {
3248 stream->print("%s", fst->name());
3249 if (snd->is_valid()) {
3250 stream->print(":%s", snd->name());
3251 }
3252 } else if (fst->is_stack()) {
3253 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
3254 if (offset == stack_slot_offset) at_old_sp = true;
3255 stream->print("[%s+0x%x]", spname, offset);
3256 } else {
3257 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
3258 }
3259 stream->print(" ");
3260 stream->move_to(tab2);
3261 stream->print("= ");
3262 if (at_this) {
3263 m->method_holder()->print_value_on(stream);
3264 } else {
3265 bool did_name = false;
3266 if (!at_this && ss.is_object()) {
3267 Symbol* name = ss.as_symbol_or_null();
3268 if (name != NULL) {
3269 name->print_value_on(stream);
3270 did_name = true;
3271 }
3272 }
3273 if (!did_name)
3274 stream->print("%s", type2name(t));
3275 }
3276 if (at_old_sp) {
3277 stream->print(" (%s of caller)", spname);
3278 did_old_sp = true;
3279 }
3280 stream->cr();
3281 sig_index += type2size[t];
3282 arg_index += 1;
3283 if (!at_this) ss.next();
3284 }
3285 if (!did_old_sp) {
3286 stream->print(" # ");
3287 stream->move_to(tab1);
3288 stream->print("[%s+0x%x]", spname, stack_slot_offset);
3289 stream->print(" (%s of caller)", spname);
3290 stream->cr();
3291 }
3292 }
3293 }
3294 }
3295
3296 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
3297 // First, find an oopmap in (begin, end].
3298 // We use the odd half-closed interval so that oop maps and scope descs
3299 // which are tied to the byte after a call are printed with the call itself.
3300 address base = code_begin();
3301 ImmutableOopMapSet* oms = oop_maps();
3302 if (oms != NULL) {
3303 for (int i = 0, imax = oms->count(); i < imax; i++) {
3304 const ImmutableOopMapPair* pair = oms->pair_at(i);
3305 const ImmutableOopMap* om = pair->get_from(oms);
3306 address pc = base + pair->pc_offset();
3307 if (pc > begin) {
3308 if (pc <= end) {
3309 st->move_to(column);
3310 st->print("; ");
3311 om->print_on(st);
3312 }
3313 break;
3314 }
3315 }
3316 }
3317
3318 // Print any debug info present at this pc.
3319 ScopeDesc* sd = scope_desc_in(begin, end);
3320 if (sd != NULL) {
3321 st->move_to(column);
3322 if (sd->bci() == SynchronizationEntryBCI) {
3323 st->print(";*synchronization entry");
3324 } else {
3325 if (sd->method() == NULL) {
3326 st->print("method is NULL");
3327 } else if (sd->method()->is_native()) {
3328 st->print("method is native");
3329 } else {
3330 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
3331 st->print(";*%s", Bytecodes::name(bc));
3332 switch (bc) {
3333 case Bytecodes::_invokevirtual:
3334 case Bytecodes::_invokespecial:
3335 case Bytecodes::_invokestatic:
3336 case Bytecodes::_invokeinterface:
3337 {
3338 Bytecode_invoke invoke(sd->method(), sd->bci());
3339 st->print(" ");
3340 if (invoke.name() != NULL)
3341 invoke.name()->print_symbol_on(st);
3342 else
3343 st->print("<UNKNOWN>");
3344 break;
3345 }
3346 case Bytecodes::_getfield:
3347 case Bytecodes::_putfield:
3348 case Bytecodes::_getstatic:
3349 case Bytecodes::_putstatic:
3350 {
3351 Bytecode_field field(sd->method(), sd->bci());
3352 st->print(" ");
3353 if (field.name() != NULL)
3354 field.name()->print_symbol_on(st);
3355 else
3356 st->print("<UNKNOWN>");
3357 }
3358 }
3359 }
3360 st->print(" {reexecute=%d rethrow=%d return_oop=%d}", sd->should_reexecute(), sd->rethrow_exception(), sd->return_oop());
3361 }
3362
3363 // Print all scopes
3364 for (;sd != NULL; sd = sd->sender()) {
3365 st->move_to(column);
3366 st->print("; -");
3367 if (sd->method() == NULL) {
3368 st->print("method is NULL");
3369 } else {
3370 sd->method()->print_short_name(st);
3371 }
3372 int lineno = sd->method()->line_number_from_bci(sd->bci());
3373 if (lineno != -1) {
3374 st->print("@%d (line %d)", sd->bci(), lineno);
3375 } else {
3376 st->print("@%d", sd->bci());
3377 }
3378 st->cr();
3379 }
3380 }
3381
3382 // Print relocation information
3383 const char* str = reloc_string_for(begin, end);
3384 if (str != NULL) {
3385 if (sd != NULL) st->cr();
3386 st->move_to(column);
3387 st->print("; {%s}", str);
3388 }
3389 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
3390 if (cont_offset != 0) {
3391 st->move_to(column);
3392 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, p2i(code_begin() + cont_offset));
3393 }
3394
3395 }
3396
3397 #ifndef PRODUCT
3398
3399 void nmethod::print_value_on(outputStream* st) const {
3400 st->print("nmethod");
3401 print_on(st, NULL);
3402 }
3403
3404 void nmethod::print_calls(outputStream* st) {
3405 RelocIterator iter(this);
3406 while (iter.next()) {
3407 switch (iter.type()) {
3408 case relocInfo::virtual_call_type:
3409 case relocInfo::opt_virtual_call_type: {
3410 VerifyMutexLocker mc(CompiledIC_lock);
3411 CompiledIC_at(&iter)->print();
3412 break;
3413 }
3414 case relocInfo::static_call_type:
3415 st->print_cr("Static call at " INTPTR_FORMAT, p2i(iter.reloc()->addr()));
3416 compiledStaticCall_at(iter.reloc())->print();
3417 break;
3418 }
3419 }
3420 }
3421
3422 void nmethod::print_handler_table() {
3423 ExceptionHandlerTable(this).print();
3424 }
3425
3426 void nmethod::print_nul_chk_table() {
3427 ImplicitExceptionTable(this).print(code_begin());
3428 }
3429
3430 void nmethod::print_statistics() {
3431 ttyLocker ttyl;
3432 if (xtty != NULL) xtty->head("statistics type='nmethod'");
3433 native_nmethod_stats.print_native_nmethod_stats();
3434 #ifdef COMPILER1
3435 c1_java_nmethod_stats.print_nmethod_stats("C1");
3436 #endif
3437 #ifdef COMPILER2
3438 c2_java_nmethod_stats.print_nmethod_stats("C2");
3439 #endif
3440 #if INCLUDE_JVMCI
3441 jvmci_java_nmethod_stats.print_nmethod_stats("JVMCI");
3442 #endif
3443 #ifdef SHARK
3444 shark_java_nmethod_stats.print_nmethod_stats("Shark");
3445 #endif
3446 unknown_java_nmethod_stats.print_nmethod_stats("Unknown");
3447 DebugInformationRecorder::print_statistics();
3448 #ifndef PRODUCT
3449 pc_nmethod_stats.print_pc_stats();
3450 #endif
3451 Dependencies::print_statistics();
3452 if (xtty != NULL) xtty->tail("statistics");
3453 }
3454
3455 #endif // !PRODUCT
3456
3457 #if INCLUDE_JVMCI
3458 void nmethod::clear_jvmci_installed_code() {
3459 // write_ref_method_pre/post can only be safely called at a
3460 // safepoint or while holding the CodeCache_lock
3461 assert(CodeCache_lock->is_locked() ||
3462 SafepointSynchronize::is_at_safepoint(), "should be performed under a lock for consistency");
3463 if (_jvmci_installed_code != NULL) {
3464 // This must be done carefully to maintain nmethod remembered sets properly
3465 BarrierSet* bs = Universe::heap()->barrier_set();
3466 bs->write_ref_nmethod_pre(&_jvmci_installed_code, this);
3467 _jvmci_installed_code = NULL;
3468 bs->write_ref_nmethod_post(&_jvmci_installed_code, this);
3469 }
3470 }
3471
3472 void nmethod::maybe_invalidate_installed_code() {
3473 assert(Patching_lock->is_locked() ||
3474 SafepointSynchronize::is_at_safepoint(), "should be performed under a lock for consistency");
3475 oop installed_code = jvmci_installed_code();
3476 if (installed_code != NULL) {
3477 nmethod* nm = (nmethod*)InstalledCode::address(installed_code);
3478 if (nm == NULL || nm != this) {
3479 // The link has been broken or the InstalledCode instance is
3480 // associated with another nmethod so do nothing.
3481 return;
3482 }
3483 if (!is_alive()) {
3484 // Break the link between nmethod and InstalledCode such that the nmethod
3485 // can subsequently be flushed safely. The link must be maintained while
3486 // the method could have live activations since invalidateInstalledCode
3487 // might want to invalidate all existing activations.
3488 InstalledCode::set_address(installed_code, 0);
3489 InstalledCode::set_entryPoint(installed_code, 0);
3490 } else if (is_not_entrant()) {
3491 // Remove the entry point so any invocation will fail but keep
3492 // the address link around that so that existing activations can
3493 // be invalidated.
3494 InstalledCode::set_entryPoint(installed_code, 0);
3495 }
3496 }
3497 }
3498
3499 void nmethod::invalidate_installed_code(Handle installedCode, TRAPS) {
3500 if (installedCode() == NULL) {
3501 THROW(vmSymbols::java_lang_NullPointerException());
3502 }
3503 jlong nativeMethod = InstalledCode::address(installedCode);
3504 nmethod* nm = (nmethod*)nativeMethod;
3505 if (nm == NULL) {
3506 // Nothing to do
3507 return;
3508 }
3509
3510 nmethodLocker nml(nm);
3511 #ifdef ASSERT
3512 {
3513 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
3514 // This relationship can only be checked safely under a lock
3515 assert(nm == NULL || !nm->is_alive() || nm->jvmci_installed_code() == installedCode(), "sanity check");
3516 }
3517 #endif
3518
3519 if (nm->is_alive()) {
3520 // The nmethod state machinery maintains the link between the
3521 // HotSpotInstalledCode and nmethod* so as long as the nmethod appears to be
3522 // alive assume there is work to do and deoptimize the nmethod.
3523 nm->mark_for_deoptimization();
3524 VM_Deoptimize op;
3525 VMThread::execute(&op);
3526 }
3527
3528 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
3529 // Check that it's still associated with the same nmethod and break
3530 // the link if it is.
3531 if (InstalledCode::address(installedCode) == nativeMethod) {
3532 InstalledCode::set_address(installedCode, 0);
3533 }
3534 }
3535
3536 char* nmethod::jvmci_installed_code_name(char* buf, size_t buflen) {
3537 if (!this->is_compiled_by_jvmci()) {
3538 return NULL;
3539 }
3540 oop installedCode = this->jvmci_installed_code();
3541 if (installedCode != NULL) {
3542 oop installedCodeName = NULL;
3543 if (installedCode->is_a(InstalledCode::klass())) {
3544 installedCodeName = InstalledCode::name(installedCode);
3545 }
3546 if (installedCodeName != NULL) {
3547 return java_lang_String::as_utf8_string(installedCodeName, buf, (int)buflen);
3548 } else {
3549 jio_snprintf(buf, buflen, "null");
3550 return buf;
3551 }
3552 }
3553 jio_snprintf(buf, buflen, "noInstalledCode");
3554 return buf;
3555 }
3556 #endif
3557
3558 Method* nmethod::attached_method(address call_instr) {
3559 assert(code_contains(call_instr), "not part of the nmethod");
3560 RelocIterator iter(this, call_instr, call_instr + 1);
3561 while (iter.next()) {
3562 if (iter.addr() == call_instr) {
3563 switch(iter.type()) {
3564 case relocInfo::static_call_type: return iter.static_call_reloc()->method_value();
3565 case relocInfo::opt_virtual_call_type: return iter.opt_virtual_call_reloc()->method_value();
3566 case relocInfo::virtual_call_type: return iter.virtual_call_reloc()->method_value();
3567 }
3568 }
3569 }
3570 return NULL; // not found
3571 }
3572
3573 Method* nmethod::attached_method_before_pc(address pc) {
3574 if (NativeCall::is_call_before(pc)) {
3575 NativeCall* ncall = nativeCall_before(pc);
3576 return attached_method(ncall->instruction_address());
3577 }
3578 return NULL; // not a call
3579 }
3580