1 /*
2 * Copyright (c) 1997, 2012, 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/nmethod.hpp"
30 #include "code/scopeDesc.hpp"
31 #include "compiler/abstractCompiler.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/compileLog.hpp"
34 #include "compiler/compilerOracle.hpp"
35 #include "compiler/disassembler.hpp"
36 #include "interpreter/bytecode.hpp"
37 #include "oops/methodData.hpp"
38 #include "prims/jvmtiRedefineClassesTrace.hpp"
39 #include "prims/jvmtiImpl.hpp"
40 #include "runtime/sharedRuntime.hpp"
41 #include "runtime/sweeper.hpp"
42 #include "utilities/dtrace.hpp"
43 #include "utilities/events.hpp"
44 #include "utilities/xmlstream.hpp"
45 #ifdef SHARK
46 #include "shark/sharkCompiler.hpp"
47 #endif
48
49 #ifdef DTRACE_ENABLED
50
51 // Only bother with this argument setup if dtrace is available
52
53 #ifndef USDT2
54 HS_DTRACE_PROBE_DECL8(hotspot, compiled__method__load,
55 const char*, int, const char*, int, const char*, int, void*, size_t);
56
57 HS_DTRACE_PROBE_DECL6(hotspot, compiled__method__unload,
58 char*, int, char*, int, char*, int);
59
60 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
61 { \
62 Method* m = (method); \
63 if (m != NULL) { \
64 Symbol* klass_name = m->klass_name(); \
65 Symbol* name = m->name(); \
66 Symbol* signature = m->signature(); \
67 HS_DTRACE_PROBE6(hotspot, compiled__method__unload, \
68 klass_name->bytes(), klass_name->utf8_length(), \
69 name->bytes(), name->utf8_length(), \
70 signature->bytes(), signature->utf8_length()); \
71 } \
72 }
73 #else /* USDT2 */
74 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
75 { \
76 Method* m = (method); \
77 if (m != NULL) { \
78 Symbol* klass_name = m->klass_name(); \
79 Symbol* name = m->name(); \
80 Symbol* signature = m->signature(); \
81 HOTSPOT_COMPILED_METHOD_UNLOAD( \
82 (char *) klass_name->bytes(), klass_name->utf8_length(), \
83 (char *) name->bytes(), name->utf8_length(), \
84 (char *) signature->bytes(), signature->utf8_length()); \
85 } \
86 }
87 #endif /* USDT2 */
88
89 #else // ndef DTRACE_ENABLED
90
91 #define DTRACE_METHOD_UNLOAD_PROBE(method)
92
93 #endif
94
95 bool nmethod::is_compiled_by_c1() const {
96 if (compiler() == NULL || method() == NULL) return false; // can happen during debug printing
97 if (is_native_method()) return false;
98 return compiler()->is_c1();
99 }
100 bool nmethod::is_compiled_by_c2() const {
101 if (compiler() == NULL || method() == NULL) return false; // can happen during debug printing
102 if (is_native_method()) return false;
103 return compiler()->is_c2();
104 }
105 bool nmethod::is_compiled_by_shark() const {
106 if (is_native_method()) return false;
107 assert(compiler() != NULL, "must be");
108 return compiler()->is_shark();
109 }
110
111
112
113 //---------------------------------------------------------------------------------
114 // NMethod statistics
115 // They are printed under various flags, including:
116 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
117 // (In the latter two cases, they like other stats are printed to the log only.)
118
119 #ifndef PRODUCT
120 // These variables are put into one block to reduce relocations
121 // and make it simpler to print from the debugger.
122 static
123 struct nmethod_stats_struct {
124 int nmethod_count;
125 int total_size;
126 int relocation_size;
127 int consts_size;
128 int insts_size;
129 int stub_size;
130 int scopes_data_size;
131 int scopes_pcs_size;
132 int dependencies_size;
133 int handler_table_size;
134 int nul_chk_table_size;
135 int oops_size;
136
137 void note_nmethod(nmethod* nm) {
138 nmethod_count += 1;
139 total_size += nm->size();
140 relocation_size += nm->relocation_size();
141 consts_size += nm->consts_size();
142 insts_size += nm->insts_size();
143 stub_size += nm->stub_size();
144 oops_size += nm->oops_size();
145 scopes_data_size += nm->scopes_data_size();
146 scopes_pcs_size += nm->scopes_pcs_size();
147 dependencies_size += nm->dependencies_size();
148 handler_table_size += nm->handler_table_size();
149 nul_chk_table_size += nm->nul_chk_table_size();
150 }
151 void print_nmethod_stats() {
152 if (nmethod_count == 0) return;
153 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
154 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
155 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
156 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
157 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size);
158 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
159 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
160 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
161 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
162 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
163 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
164 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
165 }
166
167 int native_nmethod_count;
168 int native_total_size;
169 int native_relocation_size;
170 int native_insts_size;
171 int native_oops_size;
172 void note_native_nmethod(nmethod* nm) {
173 native_nmethod_count += 1;
174 native_total_size += nm->size();
175 native_relocation_size += nm->relocation_size();
176 native_insts_size += nm->insts_size();
177 native_oops_size += nm->oops_size();
178 }
179 void print_native_nmethod_stats() {
180 if (native_nmethod_count == 0) return;
181 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
182 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
183 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
184 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size);
185 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
186 }
187
188 int pc_desc_resets; // number of resets (= number of caches)
189 int pc_desc_queries; // queries to nmethod::find_pc_desc
190 int pc_desc_approx; // number of those which have approximate true
191 int pc_desc_repeats; // number of _pc_descs[0] hits
192 int pc_desc_hits; // number of LRU cache hits
193 int pc_desc_tests; // total number of PcDesc examinations
194 int pc_desc_searches; // total number of quasi-binary search steps
195 int pc_desc_adds; // number of LUR cache insertions
196
197 void print_pc_stats() {
198 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
199 pc_desc_queries,
200 (double)(pc_desc_tests + pc_desc_searches)
201 / pc_desc_queries);
202 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
203 pc_desc_resets,
204 pc_desc_queries, pc_desc_approx,
205 pc_desc_repeats, pc_desc_hits,
206 pc_desc_tests, pc_desc_searches, pc_desc_adds);
207 }
208 } nmethod_stats;
209 #endif //PRODUCT
210
211
212 //---------------------------------------------------------------------------------
213
214
215 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
216 assert(pc != NULL, "Must be non null");
217 assert(exception.not_null(), "Must be non null");
218 assert(handler != NULL, "Must be non null");
219
220 _count = 0;
221 _exception_type = exception->klass();
222 _next = NULL;
223
224 add_address_and_handler(pc,handler);
225 }
226
227
228 address ExceptionCache::match(Handle exception, address pc) {
229 assert(pc != NULL,"Must be non null");
230 assert(exception.not_null(),"Must be non null");
231 if (exception->klass() == exception_type()) {
232 return (test_address(pc));
233 }
234
235 return NULL;
236 }
237
238
239 bool ExceptionCache::match_exception_with_space(Handle exception) {
240 assert(exception.not_null(),"Must be non null");
241 if (exception->klass() == exception_type() && count() < cache_size) {
242 return true;
243 }
244 return false;
245 }
246
247
248 address ExceptionCache::test_address(address addr) {
249 for (int i=0; i<count(); i++) {
250 if (pc_at(i) == addr) {
251 return handler_at(i);
252 }
253 }
254 return NULL;
255 }
256
257
258 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
259 if (test_address(addr) == handler) return true;
260 if (count() < cache_size) {
261 set_pc_at(count(),addr);
262 set_handler_at(count(), handler);
263 increment_count();
264 return true;
265 }
266 return false;
267 }
268
269
270 // private method for handling exception cache
271 // These methods are private, and used to manipulate the exception cache
272 // directly.
273 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
274 ExceptionCache* ec = exception_cache();
275 while (ec != NULL) {
276 if (ec->match_exception_with_space(exception)) {
277 return ec;
278 }
279 ec = ec->next();
280 }
281 return NULL;
282 }
283
284
285 //-----------------------------------------------------------------------------
286
287
288 // Helper used by both find_pc_desc methods.
289 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
290 NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
291 if (!approximate)
292 return pc->pc_offset() == pc_offset;
293 else
294 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
295 }
296
297 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
298 if (initial_pc_desc == NULL) {
299 _pc_descs[0] = NULL; // native method; no PcDescs at all
300 return;
301 }
302 NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
303 // reset the cache by filling it with benign (non-null) values
304 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
305 for (int i = 0; i < cache_size; i++)
306 _pc_descs[i] = initial_pc_desc;
307 }
308
309 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
310 NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
311 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
312
313 // Note: one might think that caching the most recently
314 // read value separately would be a win, but one would be
315 // wrong. When many threads are updating it, the cache
316 // line it's in would bounce between caches, negating
317 // any benefit.
318
319 // In order to prevent race conditions do not load cache elements
320 // repeatedly, but use a local copy:
321 PcDesc* res;
322
323 // Step one: Check the most recently added value.
324 res = _pc_descs[0];
325 if (res == NULL) return NULL; // native method; no PcDescs at all
326 if (match_desc(res, pc_offset, approximate)) {
327 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
328 return res;
329 }
330
331 // Step two: Check the rest of the LRU cache.
332 for (int i = 1; i < cache_size; ++i) {
333 res = _pc_descs[i];
334 if (res->pc_offset() < 0) break; // optimization: skip empty cache
335 if (match_desc(res, pc_offset, approximate)) {
336 NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
337 return res;
338 }
339 }
340
341 // Report failure.
342 return NULL;
343 }
344
345 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
346 NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
347 // Update the LRU cache by shifting pc_desc forward.
348 for (int i = 0; i < cache_size; i++) {
349 PcDesc* next = _pc_descs[i];
350 _pc_descs[i] = pc_desc;
351 pc_desc = next;
352 }
353 }
354
355 // adjust pcs_size so that it is a multiple of both oopSize and
356 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
357 // of oopSize, then 2*sizeof(PcDesc) is)
358 static int adjust_pcs_size(int pcs_size) {
359 int nsize = round_to(pcs_size, oopSize);
360 if ((nsize % sizeof(PcDesc)) != 0) {
361 nsize = pcs_size + sizeof(PcDesc);
362 }
363 assert((nsize % oopSize) == 0, "correct alignment");
364 return nsize;
365 }
366
367 //-----------------------------------------------------------------------------
368
369
370 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
371 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
372 assert(new_entry != NULL,"Must be non null");
373 assert(new_entry->next() == NULL, "Must be null");
374
375 if (exception_cache() != NULL) {
376 new_entry->set_next(exception_cache());
377 }
378 set_exception_cache(new_entry);
379 }
380
381 void nmethod::remove_from_exception_cache(ExceptionCache* ec) {
382 ExceptionCache* prev = NULL;
383 ExceptionCache* curr = exception_cache();
384 assert(curr != NULL, "nothing to remove");
385 // find the previous and next entry of ec
386 while (curr != ec) {
387 prev = curr;
388 curr = curr->next();
389 assert(curr != NULL, "ExceptionCache not found");
390 }
391 // now: curr == ec
392 ExceptionCache* next = curr->next();
393 if (prev == NULL) {
394 set_exception_cache(next);
395 } else {
396 prev->set_next(next);
397 }
398 delete curr;
399 }
400
401
402 // public method for accessing the exception cache
403 // These are the public access methods.
404 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
405 // We never grab a lock to read the exception cache, so we may
406 // have false negatives. This is okay, as it can only happen during
407 // the first few exception lookups for a given nmethod.
408 ExceptionCache* ec = exception_cache();
409 while (ec != NULL) {
410 address ret_val;
411 if ((ret_val = ec->match(exception,pc)) != NULL) {
412 return ret_val;
413 }
414 ec = ec->next();
415 }
416 return NULL;
417 }
418
419
420 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
421 // There are potential race conditions during exception cache updates, so we
422 // must own the ExceptionCache_lock before doing ANY modifications. Because
423 // we don't lock during reads, it is possible to have several threads attempt
424 // to update the cache with the same data. We need to check for already inserted
425 // copies of the current data before adding it.
426
427 MutexLocker ml(ExceptionCache_lock);
428 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
429
430 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
431 target_entry = new ExceptionCache(exception,pc,handler);
432 add_exception_cache_entry(target_entry);
433 }
434 }
435
436
437 //-------------end of code for ExceptionCache--------------
438
439
440 int nmethod::total_size() const {
441 return
442 consts_size() +
443 insts_size() +
444 stub_size() +
445 scopes_data_size() +
446 scopes_pcs_size() +
447 handler_table_size() +
448 nul_chk_table_size();
449 }
450
451 const char* nmethod::compile_kind() const {
452 if (is_osr_method()) return "osr";
453 if (method() != NULL && is_native_method()) return "c2n";
454 return NULL;
455 }
456
457 // Fill in default values for various flag fields
458 void nmethod::init_defaults() {
459 _state = alive;
460 _marked_for_reclamation = 0;
461 _has_flushed_dependencies = 0;
462 _speculatively_disconnected = 0;
463 _has_unsafe_access = 0;
464 _has_method_handle_invokes = 0;
465 _lazy_critical_native = 0;
466 _has_wide_vectors = 0;
467 _marked_for_deoptimization = 0;
468 _lock_count = 0;
469 _stack_traversal_mark = 0;
470 _unload_reported = false; // jvmti state
471
472 #ifdef ASSERT
473 _oops_are_stale = false;
474 #endif
475
476 _oops_do_mark_link = NULL;
477 _jmethod_id = NULL;
478 _osr_link = NULL;
479 _scavenge_root_link = NULL;
480 _scavenge_root_state = 0;
481 _saved_nmethod_link = NULL;
482 _compiler = NULL;
483
484 #ifdef HAVE_DTRACE_H
485 _trap_offset = 0;
486 #endif // def HAVE_DTRACE_H
487 }
488
489
490 nmethod* nmethod::new_native_nmethod(methodHandle method,
491 int compile_id,
492 CodeBuffer *code_buffer,
493 int vep_offset,
494 int frame_complete,
495 int frame_size,
496 ByteSize basic_lock_owner_sp_offset,
497 ByteSize basic_lock_sp_offset,
498 OopMapSet* oop_maps) {
499 code_buffer->finalize_oop_references(method);
500 // create nmethod
501 nmethod* nm = NULL;
502 {
503 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
504 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
505 guarantee(CodeCache::largest_free_block() > (CodeCacheMinimumFreeSpace + native_nmethod_size),
506 "insufficient space for native method");
507 CodeOffsets offsets;
508 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
509 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
510 nm = new (native_nmethod_size)
511 nmethod(method(), native_nmethod_size, compile_id, &offsets,
512 code_buffer, frame_size,
513 basic_lock_owner_sp_offset, basic_lock_sp_offset,
514 oop_maps);
515 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm));
516 if (PrintAssembly && nm != NULL)
517 Disassembler::decode(nm);
518 }
519 // verify nmethod
520 debug_only(if (nm) nm->verify();) // might block
521
522 if (nm != NULL) {
523 nm->log_new_nmethod();
524 }
525
526 return nm;
527 }
528
529 #ifdef HAVE_DTRACE_H
530 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
531 CodeBuffer *code_buffer,
532 int vep_offset,
533 int trap_offset,
534 int frame_complete,
535 int frame_size) {
536 code_buffer->finalize_oop_references(method);
537 // create nmethod
538 nmethod* nm = NULL;
539 {
540 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
541 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
542 guarantee(CodeCache::largest_free_block() > (CodeCacheMinimumFreeSpace + nmethod_size),
543 "insufficient space for dtrace method");
544 CodeOffsets offsets;
545 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
546 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
547 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
548
549 nm = new (nmethod_size) nmethod(method(), nmethod_size, &offsets, code_buffer, frame_size);
550
551 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
552 if (PrintAssembly && nm != NULL)
553 Disassembler::decode(nm);
554 }
555 // verify nmethod
556 debug_only(if (nm) nm->verify();) // might block
557
558 if (nm != NULL) {
559 nm->log_new_nmethod();
560 }
561
562 return nm;
563 }
564
565 #endif // def HAVE_DTRACE_H
566
567 nmethod* nmethod::new_nmethod(methodHandle method,
568 int compile_id,
569 int entry_bci,
570 CodeOffsets* offsets,
571 int orig_pc_offset,
572 DebugInformationRecorder* debug_info,
573 Dependencies* dependencies,
574 CodeBuffer* code_buffer, int frame_size,
575 OopMapSet* oop_maps,
576 ExceptionHandlerTable* handler_table,
577 ImplicitExceptionTable* nul_chk_table,
578 AbstractCompiler* compiler,
579 int comp_level
580 )
581 {
582 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
583 code_buffer->finalize_oop_references(method);
584 // create nmethod
585 nmethod* nm = NULL;
586 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
587 int nmethod_size =
588 allocation_size(code_buffer, sizeof(nmethod))
589 + adjust_pcs_size(debug_info->pcs_size())
590 + round_to(dependencies->size_in_bytes() , oopSize)
591 + round_to(handler_table->size_in_bytes(), oopSize)
592 + round_to(nul_chk_table->size_in_bytes(), oopSize)
593 + round_to(debug_info->data_size() , oopSize);
594 guarantee(CodeCache::largest_free_block() > (CodeCacheMinimumFreeSpace + nmethod_size),
595 "insufficient space for nmethod");
596 nm = new (nmethod_size)
597 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
598 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
599 oop_maps,
600 handler_table,
601 nul_chk_table,
602 compiler,
603 comp_level);
604 if (nm != NULL) {
605 // To make dependency checking during class loading fast, record
606 // the nmethod dependencies in the classes it is dependent on.
607 // This allows the dependency checking code to simply walk the
608 // class hierarchy above the loaded class, checking only nmethods
609 // which are dependent on those classes. The slow way is to
610 // check every nmethod for dependencies which makes it linear in
611 // the number of methods compiled. For applications with a lot
612 // classes the slow way is too slow.
613 for (Dependencies::DepStream deps(nm); deps.next(); ) {
614 Klass* klass = deps.context_type();
615 if (klass == NULL) continue; // ignore things like evol_method
616
617 // record this nmethod as dependent on this klass
618 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
619 }
620 }
621 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
622 if (PrintAssembly && nm != NULL)
623 Disassembler::decode(nm);
624 }
625
626 // verify nmethod
627 debug_only(if (nm) nm->verify();) // might block
628
629 if (nm != NULL) {
630 nm->log_new_nmethod();
631 }
632
633 // done
634 return nm;
635 }
636
637
638 // For native wrappers
639 nmethod::nmethod(
640 Method* method,
641 int nmethod_size,
642 int compile_id,
643 CodeOffsets* offsets,
644 CodeBuffer* code_buffer,
645 int frame_size,
646 ByteSize basic_lock_owner_sp_offset,
647 ByteSize basic_lock_sp_offset,
648 OopMapSet* oop_maps )
649 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
650 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
651 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
652 _native_basic_lock_sp_offset(basic_lock_sp_offset)
653 {
654 {
655 debug_only(No_Safepoint_Verifier nsv;)
656 assert_locked_or_safepoint(CodeCache_lock);
657
658 init_defaults();
659 _method = method;
660 _entry_bci = InvocationEntryBci;
661 // We have no exception handler or deopt handler make the
662 // values something that will never match a pc like the nmethod vtable entry
663 _exception_offset = 0;
664 _deoptimize_offset = 0;
665 _deoptimize_mh_offset = 0;
666 _orig_pc_offset = 0;
667
668 _consts_offset = data_offset();
669 _stub_offset = data_offset();
670 _oops_offset = data_offset();
671 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
672 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
673 _scopes_pcs_offset = _scopes_data_offset;
674 _dependencies_offset = _scopes_pcs_offset;
675 _handler_table_offset = _dependencies_offset;
676 _nul_chk_table_offset = _handler_table_offset;
677 _nmethod_end_offset = _nul_chk_table_offset;
678 _compile_id = compile_id;
679 _comp_level = CompLevel_none;
680 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
681 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
682 _osr_entry_point = NULL;
683 _exception_cache = NULL;
684 _pc_desc_cache.reset_to(NULL);
685
686 code_buffer->copy_values_to(this);
687 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
688 CodeCache::add_scavenge_root_nmethod(this);
689 }
690 debug_only(verify_scavenge_root_oops());
691 CodeCache::commit(this);
692 }
693
694 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
695 ttyLocker ttyl; // keep the following output all in one block
696 // This output goes directly to the tty, not the compiler log.
697 // To enable tools to match it up with the compilation activity,
698 // be sure to tag this tty output with the compile ID.
699 if (xtty != NULL) {
700 xtty->begin_head("print_native_nmethod");
701 xtty->method(_method);
702 xtty->stamp();
703 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
704 }
705 // print the header part first
706 print();
707 // then print the requested information
708 if (PrintNativeNMethods) {
709 print_code();
710 if (oop_maps != NULL) {
711 oop_maps->print();
712 }
713 }
714 if (PrintRelocations) {
715 print_relocations();
716 }
717 if (xtty != NULL) {
718 xtty->tail("print_native_nmethod");
719 }
720 }
721 }
722
723 // For dtrace wrappers
724 #ifdef HAVE_DTRACE_H
725 nmethod::nmethod(
726 Method* method,
727 int nmethod_size,
728 CodeOffsets* offsets,
729 CodeBuffer* code_buffer,
730 int frame_size)
731 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
732 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
733 _native_receiver_sp_offset(in_ByteSize(-1)),
734 _native_basic_lock_sp_offset(in_ByteSize(-1))
735 {
736 {
737 debug_only(No_Safepoint_Verifier nsv;)
738 assert_locked_or_safepoint(CodeCache_lock);
739
740 init_defaults();
741 _method = method;
742 _entry_bci = InvocationEntryBci;
743 // We have no exception handler or deopt handler make the
744 // values something that will never match a pc like the nmethod vtable entry
745 _exception_offset = 0;
746 _deoptimize_offset = 0;
747 _deoptimize_mh_offset = 0;
748 _unwind_handler_offset = -1;
749 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
750 _orig_pc_offset = 0;
751 _consts_offset = data_offset();
752 _stub_offset = data_offset();
753 _oops_offset = data_offset();
754 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
755 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
756 _scopes_pcs_offset = _scopes_data_offset;
757 _dependencies_offset = _scopes_pcs_offset;
758 _handler_table_offset = _dependencies_offset;
759 _nul_chk_table_offset = _handler_table_offset;
760 _nmethod_end_offset = _nul_chk_table_offset;
761 _compile_id = 0; // default
762 _comp_level = CompLevel_none;
763 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
764 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
765 _osr_entry_point = NULL;
766 _exception_cache = NULL;
767 _pc_desc_cache.reset_to(NULL);
768
769 code_buffer->copy_values_to(this);
770 debug_only(verify_scavenge_root_oops());
771 CodeCache::commit(this);
772 }
773
774 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
775 ttyLocker ttyl; // keep the following output all in one block
776 // This output goes directly to the tty, not the compiler log.
777 // To enable tools to match it up with the compilation activity,
778 // be sure to tag this tty output with the compile ID.
779 if (xtty != NULL) {
780 xtty->begin_head("print_dtrace_nmethod");
781 xtty->method(_method);
782 xtty->stamp();
783 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
784 }
785 // print the header part first
786 print();
787 // then print the requested information
788 if (PrintNMethods) {
789 print_code();
790 }
791 if (PrintRelocations) {
792 print_relocations();
793 }
794 if (xtty != NULL) {
795 xtty->tail("print_dtrace_nmethod");
796 }
797 }
798 }
799 #endif // def HAVE_DTRACE_H
800
801 void* nmethod::operator new(size_t size, int nmethod_size) {
802 void* alloc = CodeCache::allocate(nmethod_size);
803 guarantee(alloc != NULL, "CodeCache should have enough space");
804 return alloc;
805 }
806
807
808 nmethod::nmethod(
809 Method* method,
810 int nmethod_size,
811 int compile_id,
812 int entry_bci,
813 CodeOffsets* offsets,
814 int orig_pc_offset,
815 DebugInformationRecorder* debug_info,
816 Dependencies* dependencies,
817 CodeBuffer *code_buffer,
818 int frame_size,
819 OopMapSet* oop_maps,
820 ExceptionHandlerTable* handler_table,
821 ImplicitExceptionTable* nul_chk_table,
822 AbstractCompiler* compiler,
823 int comp_level
824 )
825 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
826 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
827 _native_receiver_sp_offset(in_ByteSize(-1)),
828 _native_basic_lock_sp_offset(in_ByteSize(-1))
829 {
830 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
831 {
832 debug_only(No_Safepoint_Verifier nsv;)
833 assert_locked_or_safepoint(CodeCache_lock);
834
835 init_defaults();
836 _method = method;
837 _entry_bci = entry_bci;
838 _compile_id = compile_id;
839 _comp_level = comp_level;
840 _compiler = compiler;
841 _orig_pc_offset = orig_pc_offset;
842
843 // Section offsets
844 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
845 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
846
847 // Exception handler and deopt handler are in the stub section
848 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
849 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
850 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
851 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
852 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
853 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
854 } else {
855 _deoptimize_mh_offset = -1;
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 && detect_scavenge_root_oops()) {
884 CodeCache::add_scavenge_root_nmethod(this);
885 }
886 debug_only(verify_scavenge_root_oops());
887
888 CodeCache::commit(this);
889
890 // Copy contents of ExceptionHandlerTable to nmethod
891 handler_table->copy_to(this);
892 nul_chk_table->copy_to(this);
893
894 // we use the information of entry points to find out if a method is
895 // static or non static
896 assert(compiler->is_c2() ||
897 _method->is_static() == (entry_point() == _verified_entry_point),
898 " entry points must be same for static methods and vice versa");
899 }
900
901 bool printnmethods = PrintNMethods
902 || CompilerOracle::should_print(_method)
903 || CompilerOracle::has_option_string(_method, "PrintNMethods");
904 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
905 print_nmethod(printnmethods);
906 }
907 }
908
909
910 // Print a short set of xml attributes to identify this nmethod. The
911 // output should be embedded in some other element.
912 void nmethod::log_identity(xmlStream* log) const {
913 log->print(" compile_id='%d'", compile_id());
914 const char* nm_kind = compile_kind();
915 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
916 if (compiler() != NULL) {
917 log->print(" compiler='%s'", compiler()->name());
918 }
919 if (TieredCompilation) {
920 log->print(" level='%d'", comp_level());
921 }
922 }
923
924
925 #define LOG_OFFSET(log, name) \
926 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
927 log->print(" " XSTR(name) "_offset='%d'" , \
928 (intptr_t)name##_begin() - (intptr_t)this)
929
930
931 void nmethod::log_new_nmethod() const {
932 if (LogCompilation && xtty != NULL) {
933 ttyLocker ttyl;
934 HandleMark hm;
935 xtty->begin_elem("nmethod");
936 log_identity(xtty);
937 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
938 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
939
940 LOG_OFFSET(xtty, relocation);
941 LOG_OFFSET(xtty, consts);
942 LOG_OFFSET(xtty, insts);
943 LOG_OFFSET(xtty, stub);
944 LOG_OFFSET(xtty, scopes_data);
945 LOG_OFFSET(xtty, scopes_pcs);
946 LOG_OFFSET(xtty, dependencies);
947 LOG_OFFSET(xtty, handler_table);
948 LOG_OFFSET(xtty, nul_chk_table);
949 LOG_OFFSET(xtty, oops);
950
951 xtty->method(method());
952 xtty->stamp();
953 xtty->end_elem();
954 }
955 }
956
957 #undef LOG_OFFSET
958
959
960 // Print out more verbose output usually for a newly created nmethod.
961 void nmethod::print_on(outputStream* st, const char* msg) const {
962 if (st != NULL) {
963 ttyLocker ttyl;
964 if (WizardMode) {
965 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
966 st->print_cr(" (" INTPTR_FORMAT ")", this);
967 } else {
968 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
969 }
970 }
971 }
972
973
974 void nmethod::print_nmethod(bool printmethod) {
975 ttyLocker ttyl; // keep the following output all in one block
976 if (xtty != NULL) {
977 xtty->begin_head("print_nmethod");
978 xtty->stamp();
979 xtty->end_head();
980 }
981 // print the header part first
982 print();
983 // then print the requested information
984 if (printmethod) {
985 print_code();
986 print_pcs();
987 if (oop_maps()) {
988 oop_maps()->print();
989 }
990 }
991 if (PrintDebugInfo) {
992 print_scopes();
993 }
994 if (PrintRelocations) {
995 print_relocations();
996 }
997 if (PrintDependencies) {
998 print_dependencies();
999 }
1000 if (PrintExceptionHandlers) {
1001 print_handler_table();
1002 print_nul_chk_table();
1003 }
1004 if (xtty != NULL) {
1005 xtty->tail("print_nmethod");
1006 }
1007 }
1008
1009
1010 // Promote one word from an assembly-time handle to a live embedded oop.
1011 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1012 if (handle == NULL ||
1013 // As a special case, IC oops are initialized to 1 or -1.
1014 handle == (jobject) Universe::non_oop_word()) {
1015 (*dest) = (oop) handle;
1016 } else {
1017 (*dest) = JNIHandles::resolve_non_null(handle);
1018 }
1019 }
1020
1021
1022 // Have to have the same name because it's called by a template
1023 void nmethod::copy_values(GrowableArray<jobject>* array) {
1024 int length = array->length();
1025 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1026 oop* dest = oops_begin();
1027 for (int index = 0 ; index < length; index++) {
1028 initialize_immediate_oop(&dest[index], array->at(index));
1029 }
1030
1031 // Now we can fix up all the oops in the code. We need to do this
1032 // in the code because the assembler uses jobjects as placeholders.
1033 // The code and relocations have already been initialized by the
1034 // CodeBlob constructor, so it is valid even at this early point to
1035 // iterate over relocations and patch the code.
1036 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1037 }
1038
1039 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1040 int length = array->length();
1041 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1042 Metadata** dest = metadata_begin();
1043 for (int index = 0 ; index < length; index++) {
1044 dest[index] = array->at(index);
1045 }
1046 }
1047
1048 bool nmethod::is_at_poll_return(address pc) {
1049 RelocIterator iter(this, pc, pc+1);
1050 while (iter.next()) {
1051 if (iter.type() == relocInfo::poll_return_type)
1052 return true;
1053 }
1054 return false;
1055 }
1056
1057
1058 bool nmethod::is_at_poll_or_poll_return(address pc) {
1059 RelocIterator iter(this, pc, pc+1);
1060 while (iter.next()) {
1061 relocInfo::relocType t = iter.type();
1062 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1063 return true;
1064 }
1065 return false;
1066 }
1067
1068
1069 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1070 // re-patch all oop-bearing instructions, just in case some oops moved
1071 RelocIterator iter(this, begin, end);
1072 while (iter.next()) {
1073 if (iter.type() == relocInfo::oop_type) {
1074 oop_Relocation* reloc = iter.oop_reloc();
1075 if (initialize_immediates && reloc->oop_is_immediate()) {
1076 oop* dest = reloc->oop_addr();
1077 initialize_immediate_oop(dest, (jobject) *dest);
1078 }
1079 // Refresh the oop-related bits of this instruction.
1080 reloc->fix_oop_relocation();
1081 } else if (iter.type() == relocInfo::metadata_type) {
1082 metadata_Relocation* reloc = iter.metadata_reloc();
1083 reloc->fix_metadata_relocation();
1084 }
1085
1086 // There must not be any interfering patches or breakpoints.
1087 assert(!(iter.type() == relocInfo::breakpoint_type
1088 && iter.breakpoint_reloc()->active()),
1089 "no active breakpoint");
1090 }
1091 }
1092
1093
1094 void nmethod::verify_oop_relocations() {
1095 // Ensure sure that the code matches the current oop values
1096 RelocIterator iter(this, NULL, NULL);
1097 while (iter.next()) {
1098 if (iter.type() == relocInfo::oop_type) {
1099 oop_Relocation* reloc = iter.oop_reloc();
1100 if (!reloc->oop_is_immediate()) {
1101 reloc->verify_oop_relocation();
1102 }
1103 }
1104 }
1105 }
1106
1107
1108 ScopeDesc* nmethod::scope_desc_at(address pc) {
1109 PcDesc* pd = pc_desc_at(pc);
1110 guarantee(pd != NULL, "scope must be present");
1111 return new ScopeDesc(this, pd->scope_decode_offset(),
1112 pd->obj_decode_offset(), pd->should_reexecute(),
1113 pd->return_oop());
1114 }
1115
1116
1117 void nmethod::clear_inline_caches() {
1118 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1119 if (is_zombie()) {
1120 return;
1121 }
1122
1123 RelocIterator iter(this);
1124 while (iter.next()) {
1125 iter.reloc()->clear_inline_cache();
1126 }
1127 }
1128
1129
1130 void nmethod::cleanup_inline_caches() {
1131
1132 assert_locked_or_safepoint(CompiledIC_lock);
1133
1134 // If the method is not entrant or zombie then a JMP is plastered over the
1135 // first few bytes. If an oop in the old code was there, that oop
1136 // should not get GC'd. Skip the first few bytes of oops on
1137 // not-entrant methods.
1138 address low_boundary = verified_entry_point();
1139 if (!is_in_use()) {
1140 low_boundary += NativeJump::instruction_size;
1141 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1142 // This means that the low_boundary is going to be a little too high.
1143 // This shouldn't matter, since oops of non-entrant methods are never used.
1144 // In fact, why are we bothering to look at oops in a non-entrant method??
1145 }
1146
1147 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1148 ResourceMark rm;
1149 RelocIterator iter(this, low_boundary);
1150 while(iter.next()) {
1151 switch(iter.type()) {
1152 case relocInfo::virtual_call_type:
1153 case relocInfo::opt_virtual_call_type: {
1154 CompiledIC *ic = CompiledIC_at(iter.reloc());
1155 // Ok, to lookup references to zombies here
1156 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1157 if( cb != NULL && cb->is_nmethod() ) {
1158 nmethod* nm = (nmethod*)cb;
1159 // Clean inline caches pointing to both zombie and not_entrant methods
1160 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1161 }
1162 break;
1163 }
1164 case relocInfo::static_call_type: {
1165 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1166 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1167 if( cb != NULL && cb->is_nmethod() ) {
1168 nmethod* nm = (nmethod*)cb;
1169 // Clean inline caches pointing to both zombie and not_entrant methods
1170 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1171 }
1172 break;
1173 }
1174 }
1175 }
1176 }
1177
1178 // This is a private interface with the sweeper.
1179 void nmethod::mark_as_seen_on_stack() {
1180 assert(is_not_entrant(), "must be a non-entrant method");
1181 // Set the traversal mark to ensure that the sweeper does 2
1182 // cleaning passes before moving to zombie.
1183 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1184 }
1185
1186 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1187 // there are no activations on the stack, not in use by the VM,
1188 // and not in use by the ServiceThread)
1189 bool nmethod::can_not_entrant_be_converted() {
1190 assert(is_not_entrant(), "must be a non-entrant method");
1191
1192 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1193 // count can be greater than the stack traversal count before it hits the
1194 // nmethod for the second time.
1195 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1196 !is_locked_by_vm();
1197 }
1198
1199 void nmethod::inc_decompile_count() {
1200 if (!is_compiled_by_c2()) return;
1201 // Could be gated by ProfileTraps, but do not bother...
1202 Method* m = method();
1203 if (m == NULL) return;
1204 MethodData* mdo = m->method_data();
1205 if (mdo == NULL) return;
1206 // There is a benign race here. See comments in methodData.hpp.
1207 mdo->inc_decompile_count();
1208 }
1209
1210 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1211
1212 post_compiled_method_unload();
1213
1214 // Since this nmethod is being unloaded, make sure that dependencies
1215 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1216 // indicate that this work is being done during a GC.
1217 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1218 assert(is_alive != NULL, "Should be non-NULL");
1219 // A non-NULL is_alive closure indicates that this is being called during GC.
1220 flush_dependencies(is_alive);
1221
1222 // Break cycle between nmethod & method
1223 if (TraceClassUnloading && WizardMode) {
1224 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1225 " unloadable], Method*(" INTPTR_FORMAT
1226 "), cause(" INTPTR_FORMAT ")",
1227 this, (address)_method, (address)cause);
1228 if (!Universe::heap()->is_gc_active())
1229 cause->klass()->print();
1230 }
1231 // Unlink the osr method, so we do not look this up again
1232 if (is_osr_method()) {
1233 invalidate_osr_method();
1234 }
1235 // If _method is already NULL the Method* is about to be unloaded,
1236 // so we don't have to break the cycle. Note that it is possible to
1237 // have the Method* live here, in case we unload the nmethod because
1238 // it is pointing to some oop (other than the Method*) being unloaded.
1239 if (_method != NULL) {
1240 // OSR methods point to the Method*, but the Method* does not
1241 // point back!
1242 if (_method->code() == this) {
1243 _method->clear_code(); // Break a cycle
1244 }
1245 _method = NULL; // Clear the method of this dead nmethod
1246 }
1247 // Make the class unloaded - i.e., change state and notify sweeper
1248 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1249 if (is_in_use()) {
1250 // Transitioning directly from live to unloaded -- so
1251 // we need to force a cache clean-up; remember this
1252 // for later on.
1253 CodeCache::set_needs_cache_clean(true);
1254 }
1255 _state = unloaded;
1256
1257 // Log the unloading.
1258 log_state_change();
1259
1260 // The Method* is gone at this point
1261 assert(_method == NULL, "Tautology");
1262
1263 set_osr_link(NULL);
1264 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1265 NMethodSweeper::notify(this);
1266 }
1267
1268 void nmethod::invalidate_osr_method() {
1269 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1270 // Remove from list of active nmethods
1271 if (method() != NULL)
1272 method()->method_holder()->remove_osr_nmethod(this);
1273 // Set entry as invalid
1274 _entry_bci = InvalidOSREntryBci;
1275 }
1276
1277 void nmethod::log_state_change() const {
1278 if (LogCompilation) {
1279 if (xtty != NULL) {
1280 ttyLocker ttyl; // keep the following output all in one block
1281 if (_state == unloaded) {
1282 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1283 os::current_thread_id());
1284 } else {
1285 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1286 os::current_thread_id(),
1287 (_state == zombie ? " zombie='1'" : ""));
1288 }
1289 log_identity(xtty);
1290 xtty->stamp();
1291 xtty->end_elem();
1292 }
1293 }
1294 if (PrintCompilation && _state != unloaded) {
1295 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1296 }
1297 }
1298
1299 // Common functionality for both make_not_entrant and make_zombie
1300 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1301 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1302 assert(!is_zombie(), "should not already be a zombie");
1303
1304 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1305 nmethodLocker nml(this);
1306 methodHandle the_method(method());
1307 No_Safepoint_Verifier nsv;
1308
1309 {
1310 // invalidate osr nmethod before acquiring the patching lock since
1311 // they both acquire leaf locks and we don't want a deadlock.
1312 // This logic is equivalent to the logic below for patching the
1313 // verified entry point of regular methods.
1314 if (is_osr_method()) {
1315 // this effectively makes the osr nmethod not entrant
1316 invalidate_osr_method();
1317 }
1318
1319 // Enter critical section. Does not block for safepoint.
1320 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1321
1322 if (_state == state) {
1323 // another thread already performed this transition so nothing
1324 // to do, but return false to indicate this.
1325 return false;
1326 }
1327
1328 // The caller can be calling the method statically or through an inline
1329 // cache call.
1330 if (!is_osr_method() && !is_not_entrant()) {
1331 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1332 SharedRuntime::get_handle_wrong_method_stub());
1333 }
1334
1335 if (is_in_use()) {
1336 // It's a true state change, so mark the method as decompiled.
1337 // Do it only for transition from alive.
1338 inc_decompile_count();
1339 }
1340
1341 // Change state
1342 _state = state;
1343
1344 // Log the transition once
1345 log_state_change();
1346
1347 // Remove nmethod from method.
1348 // We need to check if both the _code and _from_compiled_code_entry_point
1349 // refer to this nmethod because there is a race in setting these two fields
1350 // in Method* as seen in bugid 4947125.
1351 // If the vep() points to the zombie nmethod, the memory for the nmethod
1352 // could be flushed and the compiler and vtable stubs could still call
1353 // through it.
1354 if (method() != NULL && (method()->code() == this ||
1355 method()->from_compiled_entry() == verified_entry_point())) {
1356 HandleMark hm;
1357 method()->clear_code();
1358 }
1359
1360 if (state == not_entrant) {
1361 mark_as_seen_on_stack();
1362 }
1363
1364 } // leave critical region under Patching_lock
1365
1366 // When the nmethod becomes zombie it is no longer alive so the
1367 // dependencies must be flushed. nmethods in the not_entrant
1368 // state will be flushed later when the transition to zombie
1369 // happens or they get unloaded.
1370 if (state == zombie) {
1371 {
1372 // Flushing dependecies must be done before any possible
1373 // safepoint can sneak in, otherwise the oops used by the
1374 // dependency logic could have become stale.
1375 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1376 flush_dependencies(NULL);
1377 }
1378
1379 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1380 // event and it hasn't already been reported for this nmethod then
1381 // report it now. The event may have been reported earilier if the GC
1382 // marked it for unloading). JvmtiDeferredEventQueue support means
1383 // we no longer go to a safepoint here.
1384 post_compiled_method_unload();
1385
1386 #ifdef ASSERT
1387 // It's no longer safe to access the oops section since zombie
1388 // nmethods aren't scanned for GC.
1389 _oops_are_stale = true;
1390 #endif
1391 } else {
1392 assert(state == not_entrant, "other cases may need to be handled differently");
1393 }
1394
1395 if (TraceCreateZombies) {
1396 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1397 }
1398
1399 // Make sweeper aware that there is a zombie method that needs to be removed
1400 NMethodSweeper::notify(this);
1401
1402 return true;
1403 }
1404
1405 void nmethod::flush() {
1406 // Note that there are no valid oops in the nmethod anymore.
1407 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1408 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1409
1410 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1411 assert_locked_or_safepoint(CodeCache_lock);
1412
1413 // completely deallocate this method
1414 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1415 if (PrintMethodFlushing) {
1416 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1417 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
1418 }
1419
1420 // We need to deallocate any ExceptionCache data.
1421 // Note that we do not need to grab the nmethod lock for this, it
1422 // better be thread safe if we're disposing of it!
1423 ExceptionCache* ec = exception_cache();
1424 set_exception_cache(NULL);
1425 while(ec != NULL) {
1426 ExceptionCache* next = ec->next();
1427 delete ec;
1428 ec = next;
1429 }
1430
1431 if (on_scavenge_root_list()) {
1432 CodeCache::drop_scavenge_root_nmethod(this);
1433 }
1434
1435 if (is_speculatively_disconnected()) {
1436 CodeCache::remove_saved_code(this);
1437 }
1438
1439 #ifdef SHARK
1440 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1441 #endif // SHARK
1442
1443 ((CodeBlob*)(this))->flush();
1444
1445 CodeCache::free(this);
1446 }
1447
1448
1449 //
1450 // Notify all classes this nmethod is dependent on that it is no
1451 // longer dependent. This should only be called in two situations.
1452 // First, when a nmethod transitions to a zombie all dependents need
1453 // to be clear. Since zombification happens at a safepoint there's no
1454 // synchronization issues. The second place is a little more tricky.
1455 // During phase 1 of mark sweep class unloading may happen and as a
1456 // result some nmethods may get unloaded. In this case the flushing
1457 // of dependencies must happen during phase 1 since after GC any
1458 // dependencies in the unloaded nmethod won't be updated, so
1459 // traversing the dependency information in unsafe. In that case this
1460 // function is called with a non-NULL argument and this function only
1461 // notifies instanceKlasses that are reachable
1462
1463 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1464 assert_locked_or_safepoint(CodeCache_lock);
1465 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1466 "is_alive is non-NULL if and only if we are called during GC");
1467 if (!has_flushed_dependencies()) {
1468 set_has_flushed_dependencies();
1469 for (Dependencies::DepStream deps(this); deps.next(); ) {
1470 Klass* klass = deps.context_type();
1471 if (klass == NULL) continue; // ignore things like evol_method
1472
1473 // During GC the is_alive closure is non-NULL, and is used to
1474 // determine liveness of dependees that need to be updated.
1475 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1476 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1477 }
1478 }
1479 }
1480 }
1481
1482
1483 // If this oop is not live, the nmethod can be unloaded.
1484 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1485 assert(root != NULL, "just checking");
1486 oop obj = *root;
1487 if (obj == NULL || is_alive->do_object_b(obj)) {
1488 return false;
1489 }
1490
1491 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1492 // simply because one of its constant oops has gone dead.
1493 // No actual classes need to be unloaded in order for this to occur.
1494 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1495 make_unloaded(is_alive, obj);
1496 return true;
1497 }
1498
1499 // ------------------------------------------------------------------
1500 // post_compiled_method_load_event
1501 // new method for install_code() path
1502 // Transfer information from compilation to jvmti
1503 void nmethod::post_compiled_method_load_event() {
1504
1505 Method* moop = method();
1506 #ifndef USDT2
1507 HS_DTRACE_PROBE8(hotspot, compiled__method__load,
1508 moop->klass_name()->bytes(),
1509 moop->klass_name()->utf8_length(),
1510 moop->name()->bytes(),
1511 moop->name()->utf8_length(),
1512 moop->signature()->bytes(),
1513 moop->signature()->utf8_length(),
1514 insts_begin(), insts_size());
1515 #else /* USDT2 */
1516 HOTSPOT_COMPILED_METHOD_LOAD(
1517 (char *) moop->klass_name()->bytes(),
1518 moop->klass_name()->utf8_length(),
1519 (char *) moop->name()->bytes(),
1520 moop->name()->utf8_length(),
1521 (char *) moop->signature()->bytes(),
1522 moop->signature()->utf8_length(),
1523 insts_begin(), insts_size());
1524 #endif /* USDT2 */
1525
1526 if (JvmtiExport::should_post_compiled_method_load() ||
1527 JvmtiExport::should_post_compiled_method_unload()) {
1528 get_and_cache_jmethod_id();
1529 }
1530
1531 if (JvmtiExport::should_post_compiled_method_load()) {
1532 // Let the Service thread (which is a real Java thread) post the event
1533 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1534 JvmtiDeferredEventQueue::enqueue(
1535 JvmtiDeferredEvent::compiled_method_load_event(this));
1536 }
1537 }
1538
1539 jmethodID nmethod::get_and_cache_jmethod_id() {
1540 if (_jmethod_id == NULL) {
1541 // Cache the jmethod_id since it can no longer be looked up once the
1542 // method itself has been marked for unloading.
1543 _jmethod_id = method()->jmethod_id();
1544 }
1545 return _jmethod_id;
1546 }
1547
1548 void nmethod::post_compiled_method_unload() {
1549 if (unload_reported()) {
1550 // During unloading we transition to unloaded and then to zombie
1551 // and the unloading is reported during the first transition.
1552 return;
1553 }
1554
1555 assert(_method != NULL && !is_unloaded(), "just checking");
1556 DTRACE_METHOD_UNLOAD_PROBE(method());
1557
1558 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1559 // post the event. Sometime later this nmethod will be made a zombie
1560 // by the sweeper but the Method* will not be valid at that point.
1561 // If the _jmethod_id is null then no load event was ever requested
1562 // so don't bother posting the unload. The main reason for this is
1563 // that the jmethodID is a weak reference to the Method* so if
1564 // it's being unloaded there's no way to look it up since the weak
1565 // ref will have been cleared.
1566 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1567 assert(!unload_reported(), "already unloaded");
1568 JvmtiDeferredEvent event =
1569 JvmtiDeferredEvent::compiled_method_unload_event(this,
1570 _jmethod_id, insts_begin());
1571 if (SafepointSynchronize::is_at_safepoint()) {
1572 // Don't want to take the queueing lock. Add it as pending and
1573 // it will get enqueued later.
1574 JvmtiDeferredEventQueue::add_pending_event(event);
1575 } else {
1576 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1577 JvmtiDeferredEventQueue::enqueue(event);
1578 }
1579 }
1580
1581 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1582 // any time. As the nmethod is being unloaded now we mark it has
1583 // having the unload event reported - this will ensure that we don't
1584 // attempt to report the event in the unlikely scenario where the
1585 // event is enabled at the time the nmethod is made a zombie.
1586 set_unload_reported();
1587 }
1588
1589 // This is called at the end of the strong tracing/marking phase of a
1590 // GC to unload an nmethod if it contains otherwise unreachable
1591 // oops.
1592
1593 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1594 // Make sure the oop's ready to receive visitors
1595 assert(!is_zombie() && !is_unloaded(),
1596 "should not call follow on zombie or unloaded nmethod");
1597
1598 // If the method is not entrant then a JMP is plastered over the
1599 // first few bytes. If an oop in the old code was there, that oop
1600 // should not get GC'd. Skip the first few bytes of oops on
1601 // not-entrant methods.
1602 address low_boundary = verified_entry_point();
1603 if (is_not_entrant()) {
1604 low_boundary += NativeJump::instruction_size;
1605 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1606 // (See comment above.)
1607 }
1608
1609 // The RedefineClasses() API can cause the class unloading invariant
1610 // to no longer be true. See jvmtiExport.hpp for details.
1611 // Also, leave a debugging breadcrumb in local flag.
1612 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1613 if (a_class_was_redefined) {
1614 // This set of the unloading_occurred flag is done before the
1615 // call to post_compiled_method_unload() so that the unloading
1616 // of this nmethod is reported.
1617 unloading_occurred = true;
1618 }
1619
1620 // Exception cache
1621 ExceptionCache* ec = exception_cache();
1622 while (ec != NULL) {
1623 Klass* ex_klass = ec->exception_type();
1624 ExceptionCache* next_ec = ec->next();
1625 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
1626 remove_from_exception_cache(ec);
1627 }
1628 ec = next_ec;
1629 }
1630
1631 // If class unloading occurred we first iterate over all inline caches and
1632 // clear ICs where the cached oop is referring to an unloaded klass or method.
1633 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1634 // iteration below.
1635 if (unloading_occurred) {
1636 RelocIterator iter(this, low_boundary);
1637 while(iter.next()) {
1638 if (iter.type() == relocInfo::virtual_call_type) {
1639 CompiledIC *ic = CompiledIC_at(iter.reloc());
1640 if (ic->is_icholder_call()) {
1641 // The only exception is compiledICHolder oops which may
1642 // yet be marked below. (We check this further below).
1643 CompiledICHolder* cichk_oop = ic->cached_icholder();
1644 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1645 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1646 continue;
1647 }
1648 } else {
1649 Metadata* ic_oop = ic->cached_metadata();
1650 if (ic_oop != NULL) {
1651 if (ic_oop->is_klass()) {
1652 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1653 continue;
1654 }
1655 } else if (ic_oop->is_method()) {
1656 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1657 continue;
1658 }
1659 } else {
1660 ShouldNotReachHere();
1661 }
1662 }
1663 }
1664 ic->set_to_clean();
1665 }
1666 }
1667 }
1668
1669 // Compiled code
1670 {
1671 RelocIterator iter(this, low_boundary);
1672 while (iter.next()) {
1673 if (iter.type() == relocInfo::oop_type) {
1674 oop_Relocation* r = iter.oop_reloc();
1675 // In this loop, we must only traverse those oops directly embedded in
1676 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1677 assert(1 == (r->oop_is_immediate()) +
1678 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1679 "oop must be found in exactly one place");
1680 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1681 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1682 return;
1683 }
1684 }
1685 }
1686 }
1687 }
1688
1689
1690 // Scopes
1691 for (oop* p = oops_begin(); p < oops_end(); p++) {
1692 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1693 if (can_unload(is_alive, p, unloading_occurred)) {
1694 return;
1695 }
1696 }
1697
1698 // Ensure that all metadata is still alive
1699 verify_metadata_loaders(low_boundary, is_alive);
1700 }
1701
1702 #ifdef ASSERT
1703
1704 class CheckClass : AllStatic {
1705 static BoolObjectClosure* _is_alive;
1706
1707 // Check class_loader is alive for this bit of metadata.
1708 static void check_class(Metadata* md) {
1709 Klass* klass = NULL;
1710 if (md->is_klass()) {
1711 klass = ((Klass*)md);
1712 } else if (md->is_method()) {
1713 klass = ((Method*)md)->method_holder();
1714 } else if (md->is_methodData()) {
1715 klass = ((MethodData*)md)->method()->method_holder();
1716 } else {
1717 md->print();
1718 ShouldNotReachHere();
1719 }
1720 assert(klass->is_loader_alive(_is_alive), "must be alive");
1721 }
1722 public:
1723 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
1724 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
1725 _is_alive = is_alive;
1726 nm->metadata_do(check_class);
1727 }
1728 };
1729
1730 // This is called during a safepoint so can use static data
1731 BoolObjectClosure* CheckClass::_is_alive = NULL;
1732 #endif // ASSERT
1733
1734
1735 // Processing of oop references should have been sufficient to keep
1736 // all strong references alive. Any weak references should have been
1737 // cleared as well. Visit all the metadata and ensure that it's
1738 // really alive.
1739 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
1740 #ifdef ASSERT
1741 RelocIterator iter(this, low_boundary);
1742 while (iter.next()) {
1743 // static_stub_Relocations may have dangling references to
1744 // Method*s so trim them out here. Otherwise it looks like
1745 // compiled code is maintaining a link to dead metadata.
1746 address static_call_addr = NULL;
1747 if (iter.type() == relocInfo::opt_virtual_call_type) {
1748 CompiledIC* cic = CompiledIC_at(iter.reloc());
1749 if (!cic->is_call_to_interpreted()) {
1750 static_call_addr = iter.addr();
1751 }
1752 } else if (iter.type() == relocInfo::static_call_type) {
1753 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
1754 if (!csc->is_call_to_interpreted()) {
1755 static_call_addr = iter.addr();
1756 }
1757 }
1758 if (static_call_addr != NULL) {
1759 RelocIterator sciter(this, low_boundary);
1760 while (sciter.next()) {
1761 if (sciter.type() == relocInfo::static_stub_type &&
1762 sciter.static_stub_reloc()->static_call() == static_call_addr) {
1763 sciter.static_stub_reloc()->clear_inline_cache();
1764 }
1765 }
1766 }
1767 }
1768 // Check that the metadata embedded in the nmethod is alive
1769 CheckClass::do_check_class(is_alive, this);
1770 #endif
1771 }
1772
1773
1774 // Iterate over metadata calling this function. Used by RedefineClasses
1775 void nmethod::metadata_do(void f(Metadata*)) {
1776 address low_boundary = verified_entry_point();
1777 if (is_not_entrant()) {
1778 low_boundary += NativeJump::instruction_size;
1779 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1780 // (See comment above.)
1781 }
1782 {
1783 // Visit all immediate references that are embedded in the instruction stream.
1784 RelocIterator iter(this, low_boundary);
1785 while (iter.next()) {
1786 if (iter.type() == relocInfo::metadata_type ) {
1787 metadata_Relocation* r = iter.metadata_reloc();
1788 // In this lmetadata, we must only follow those metadatas directly embedded in
1789 // the code. Other metadatas (oop_index>0) are seen as part of
1790 // the metadata section below.
1791 assert(1 == (r->metadata_is_immediate()) +
1792 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1793 "metadata must be found in exactly one place");
1794 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1795 Metadata* md = r->metadata_value();
1796 f(md);
1797 }
1798 }
1799 }
1800 }
1801
1802 // Visit the metadata section
1803 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1804 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
1805 Metadata* md = *p;
1806 f(md);
1807 }
1808 // Call function Method*, not embedded in these other places.
1809 if (_method != NULL) f(_method);
1810 }
1811
1812
1813 // This method is called twice during GC -- once while
1814 // tracing the "active" nmethods on thread stacks during
1815 // the (strong) marking phase, and then again when walking
1816 // the code cache contents during the weak roots processing
1817 // phase. The two uses are distinguished by means of the
1818 // 'do_strong_roots_only' flag, which is true in the first
1819 // case. We want to walk the weak roots in the nmethod
1820 // only in the second case. The weak roots in the nmethod
1821 // are the oops in the ExceptionCache and the InlineCache
1822 // oops.
1823 void nmethod::oops_do(OopClosure* f, bool do_strong_roots_only) {
1824 // make sure the oops ready to receive visitors
1825 assert(!is_zombie() && !is_unloaded(),
1826 "should not call follow on zombie or unloaded nmethod");
1827
1828 // If the method is not entrant or zombie then a JMP is plastered over the
1829 // first few bytes. If an oop in the old code was there, that oop
1830 // should not get GC'd. Skip the first few bytes of oops on
1831 // not-entrant methods.
1832 address low_boundary = verified_entry_point();
1833 if (is_not_entrant()) {
1834 low_boundary += NativeJump::instruction_size;
1835 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1836 // (See comment above.)
1837 }
1838
1839 RelocIterator iter(this, low_boundary);
1840
1841 while (iter.next()) {
1842 if (iter.type() == relocInfo::oop_type ) {
1843 oop_Relocation* r = iter.oop_reloc();
1844 // In this loop, we must only follow those oops directly embedded in
1845 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1846 assert(1 == (r->oop_is_immediate()) +
1847 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1848 "oop must be found in exactly one place");
1849 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1850 f->do_oop(r->oop_addr());
1851 }
1852 }
1853 }
1854
1855 // Scopes
1856 // This includes oop constants not inlined in the code stream.
1857 for (oop* p = oops_begin(); p < oops_end(); p++) {
1858 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1859 f->do_oop(p);
1860 }
1861 }
1862
1863 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1864
1865 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1866
1867 // An nmethod is "marked" if its _mark_link is set non-null.
1868 // Even if it is the end of the linked list, it will have a non-null link value,
1869 // as long as it is on the list.
1870 // This code must be MP safe, because it is used from parallel GC passes.
1871 bool nmethod::test_set_oops_do_mark() {
1872 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1873 nmethod* observed_mark_link = _oops_do_mark_link;
1874 if (observed_mark_link == NULL) {
1875 // Claim this nmethod for this thread to mark.
1876 observed_mark_link = (nmethod*)
1877 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1878 if (observed_mark_link == NULL) {
1879
1880 // Atomically append this nmethod (now claimed) to the head of the list:
1881 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1882 for (;;) {
1883 nmethod* required_mark_nmethods = observed_mark_nmethods;
1884 _oops_do_mark_link = required_mark_nmethods;
1885 observed_mark_nmethods = (nmethod*)
1886 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1887 if (observed_mark_nmethods == required_mark_nmethods)
1888 break;
1889 }
1890 // Mark was clear when we first saw this guy.
1891 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
1892 return false;
1893 }
1894 }
1895 // On fall through, another racing thread marked this nmethod before we did.
1896 return true;
1897 }
1898
1899 void nmethod::oops_do_marking_prologue() {
1900 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
1901 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1902 // We use cmpxchg_ptr instead of regular assignment here because the user
1903 // may fork a bunch of threads, and we need them all to see the same state.
1904 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1905 guarantee(observed == NULL, "no races in this sequential code");
1906 }
1907
1908 void nmethod::oops_do_marking_epilogue() {
1909 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1910 nmethod* cur = _oops_do_mark_nmethods;
1911 while (cur != NMETHOD_SENTINEL) {
1912 assert(cur != NULL, "not NULL-terminated");
1913 nmethod* next = cur->_oops_do_mark_link;
1914 cur->_oops_do_mark_link = NULL;
1915 cur->fix_oop_relocations();
1916 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
1917 cur = next;
1918 }
1919 void* required = _oops_do_mark_nmethods;
1920 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1921 guarantee(observed == required, "no races in this sequential code");
1922 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
1923 }
1924
1925 class DetectScavengeRoot: public OopClosure {
1926 bool _detected_scavenge_root;
1927 public:
1928 DetectScavengeRoot() : _detected_scavenge_root(false)
1929 { NOT_PRODUCT(_print_nm = NULL); }
1930 bool detected_scavenge_root() { return _detected_scavenge_root; }
1931 virtual void do_oop(oop* p) {
1932 if ((*p) != NULL && (*p)->is_scavengable()) {
1933 NOT_PRODUCT(maybe_print(p));
1934 _detected_scavenge_root = true;
1935 }
1936 }
1937 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1938
1939 #ifndef PRODUCT
1940 nmethod* _print_nm;
1941 void maybe_print(oop* p) {
1942 if (_print_nm == NULL) return;
1943 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
1944 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
1945 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
1946 (intptr_t)(*p), (intptr_t)p);
1947 (*p)->print();
1948 }
1949 #endif //PRODUCT
1950 };
1951
1952 bool nmethod::detect_scavenge_root_oops() {
1953 DetectScavengeRoot detect_scavenge_root;
1954 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
1955 oops_do(&detect_scavenge_root);
1956 return detect_scavenge_root.detected_scavenge_root();
1957 }
1958
1959 // Method that knows how to preserve outgoing arguments at call. This method must be
1960 // called with a frame corresponding to a Java invoke
1961 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1962 #ifndef SHARK
1963 if (!method()->is_native()) {
1964 SimpleScopeDesc ssd(this, fr.pc());
1965 Bytecode_invoke call(ssd.method(), ssd.bci());
1966 // compiled invokedynamic call sites have an implicit receiver at
1967 // resolution time, so make sure it gets GC'ed.
1968 bool has_receiver = !call.is_invokestatic();
1969 Symbol* signature = call.signature();
1970 fr.oops_compiled_arguments_do(signature, has_receiver, reg_map, f);
1971 }
1972 #endif // !SHARK
1973 }
1974
1975
1976 oop nmethod::embeddedOop_at(u_char* p) {
1977 RelocIterator iter(this, p, p + 1);
1978 while (iter.next())
1979 if (iter.type() == relocInfo::oop_type) {
1980 return iter.oop_reloc()->oop_value();
1981 }
1982 return NULL;
1983 }
1984
1985
1986 inline bool includes(void* p, void* from, void* to) {
1987 return from <= p && p < to;
1988 }
1989
1990
1991 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1992 assert(count >= 2, "must be sentinel values, at least");
1993
1994 #ifdef ASSERT
1995 // must be sorted and unique; we do a binary search in find_pc_desc()
1996 int prev_offset = pcs[0].pc_offset();
1997 assert(prev_offset == PcDesc::lower_offset_limit,
1998 "must start with a sentinel");
1999 for (int i = 1; i < count; i++) {
2000 int this_offset = pcs[i].pc_offset();
2001 assert(this_offset > prev_offset, "offsets must be sorted");
2002 prev_offset = this_offset;
2003 }
2004 assert(prev_offset == PcDesc::upper_offset_limit,
2005 "must end with a sentinel");
2006 #endif //ASSERT
2007
2008 // Search for MethodHandle invokes and tag the nmethod.
2009 for (int i = 0; i < count; i++) {
2010 if (pcs[i].is_method_handle_invoke()) {
2011 set_has_method_handle_invokes(true);
2012 break;
2013 }
2014 }
2015 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2016
2017 int size = count * sizeof(PcDesc);
2018 assert(scopes_pcs_size() >= size, "oob");
2019 memcpy(scopes_pcs_begin(), pcs, size);
2020
2021 // Adjust the final sentinel downward.
2022 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2023 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2024 last_pc->set_pc_offset(content_size() + 1);
2025 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2026 // Fill any rounding gaps with copies of the last record.
2027 last_pc[1] = last_pc[0];
2028 }
2029 // The following assert could fail if sizeof(PcDesc) is not
2030 // an integral multiple of oopSize (the rounding term).
2031 // If it fails, change the logic to always allocate a multiple
2032 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2033 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2034 }
2035
2036 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2037 assert(scopes_data_size() >= size, "oob");
2038 memcpy(scopes_data_begin(), buffer, size);
2039 }
2040
2041
2042 #ifdef ASSERT
2043 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2044 PcDesc* lower = nm->scopes_pcs_begin();
2045 PcDesc* upper = nm->scopes_pcs_end();
2046 lower += 1; // exclude initial sentinel
2047 PcDesc* res = NULL;
2048 for (PcDesc* p = lower; p < upper; p++) {
2049 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2050 if (match_desc(p, pc_offset, approximate)) {
2051 if (res == NULL)
2052 res = p;
2053 else
2054 res = (PcDesc*) badAddress;
2055 }
2056 }
2057 return res;
2058 }
2059 #endif
2060
2061
2062 // Finds a PcDesc with real-pc equal to "pc"
2063 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2064 address base_address = code_begin();
2065 if ((pc < base_address) ||
2066 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2067 return NULL; // PC is wildly out of range
2068 }
2069 int pc_offset = (int) (pc - base_address);
2070
2071 // Check the PcDesc cache if it contains the desired PcDesc
2072 // (This as an almost 100% hit rate.)
2073 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2074 if (res != NULL) {
2075 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2076 return res;
2077 }
2078
2079 // Fallback algorithm: quasi-linear search for the PcDesc
2080 // Find the last pc_offset less than the given offset.
2081 // The successor must be the required match, if there is a match at all.
2082 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2083 PcDesc* lower = scopes_pcs_begin();
2084 PcDesc* upper = scopes_pcs_end();
2085 upper -= 1; // exclude final sentinel
2086 if (lower >= upper) return NULL; // native method; no PcDescs at all
2087
2088 #define assert_LU_OK \
2089 /* invariant on lower..upper during the following search: */ \
2090 assert(lower->pc_offset() < pc_offset, "sanity"); \
2091 assert(upper->pc_offset() >= pc_offset, "sanity")
2092 assert_LU_OK;
2093
2094 // Use the last successful return as a split point.
2095 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2096 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2097 if (mid->pc_offset() < pc_offset) {
2098 lower = mid;
2099 } else {
2100 upper = mid;
2101 }
2102
2103 // Take giant steps at first (4096, then 256, then 16, then 1)
2104 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2105 const int RADIX = (1 << LOG2_RADIX);
2106 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2107 while ((mid = lower + step) < upper) {
2108 assert_LU_OK;
2109 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2110 if (mid->pc_offset() < pc_offset) {
2111 lower = mid;
2112 } else {
2113 upper = mid;
2114 break;
2115 }
2116 }
2117 assert_LU_OK;
2118 }
2119
2120 // Sneak up on the value with a linear search of length ~16.
2121 while (true) {
2122 assert_LU_OK;
2123 mid = lower + 1;
2124 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2125 if (mid->pc_offset() < pc_offset) {
2126 lower = mid;
2127 } else {
2128 upper = mid;
2129 break;
2130 }
2131 }
2132 #undef assert_LU_OK
2133
2134 if (match_desc(upper, pc_offset, approximate)) {
2135 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2136 _pc_desc_cache.add_pc_desc(upper);
2137 return upper;
2138 } else {
2139 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2140 return NULL;
2141 }
2142 }
2143
2144
2145 bool nmethod::check_all_dependencies() {
2146 bool found_check = false;
2147 // wholesale check of all dependencies
2148 for (Dependencies::DepStream deps(this); deps.next(); ) {
2149 if (deps.check_dependency() != NULL) {
2150 found_check = true;
2151 NOT_DEBUG(break);
2152 }
2153 }
2154 return found_check; // tell caller if we found anything
2155 }
2156
2157 bool nmethod::check_dependency_on(DepChange& changes) {
2158 // What has happened:
2159 // 1) a new class dependee has been added
2160 // 2) dependee and all its super classes have been marked
2161 bool found_check = false; // set true if we are upset
2162 for (Dependencies::DepStream deps(this); deps.next(); ) {
2163 // Evaluate only relevant dependencies.
2164 if (deps.spot_check_dependency_at(changes) != NULL) {
2165 found_check = true;
2166 NOT_DEBUG(break);
2167 }
2168 }
2169 return found_check;
2170 }
2171
2172 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2173 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2174 Array<Method*>* dependee_methods = dependee_ik->methods();
2175 for (Dependencies::DepStream deps(this); deps.next(); ) {
2176 if (deps.type() == Dependencies::evol_method) {
2177 Method* method = deps.method_argument(0);
2178 for (int j = 0; j < dependee_methods->length(); j++) {
2179 if (dependee_methods->at(j) == method) {
2180 // RC_TRACE macro has an embedded ResourceMark
2181 RC_TRACE(0x01000000,
2182 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2183 _method->method_holder()->external_name(),
2184 _method->name()->as_C_string(),
2185 _method->signature()->as_C_string(), compile_id(),
2186 method->method_holder()->external_name(),
2187 method->name()->as_C_string(),
2188 method->signature()->as_C_string()));
2189 if (TraceDependencies || LogCompilation)
2190 deps.log_dependency(dependee);
2191 return true;
2192 }
2193 }
2194 }
2195 }
2196 return false;
2197 }
2198
2199 // Called from mark_for_deoptimization, when dependee is invalidated.
2200 bool nmethod::is_dependent_on_method(Method* dependee) {
2201 for (Dependencies::DepStream deps(this); deps.next(); ) {
2202 if (deps.type() != Dependencies::evol_method)
2203 continue;
2204 Method* method = deps.method_argument(0);
2205 if (method == dependee) return true;
2206 }
2207 return false;
2208 }
2209
2210
2211 bool nmethod::is_patchable_at(address instr_addr) {
2212 assert(insts_contains(instr_addr), "wrong nmethod used");
2213 if (is_zombie()) {
2214 // a zombie may never be patched
2215 return false;
2216 }
2217 return true;
2218 }
2219
2220
2221 address nmethod::continuation_for_implicit_exception(address pc) {
2222 // Exception happened outside inline-cache check code => we are inside
2223 // an active nmethod => use cpc to determine a return address
2224 int exception_offset = pc - code_begin();
2225 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2226 #ifdef ASSERT
2227 if (cont_offset == 0) {
2228 Thread* thread = ThreadLocalStorage::get_thread_slow();
2229 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2230 HandleMark hm(thread);
2231 ResourceMark rm(thread);
2232 CodeBlob* cb = CodeCache::find_blob(pc);
2233 assert(cb != NULL && cb == this, "");
2234 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2235 print();
2236 method()->print_codes();
2237 print_code();
2238 print_pcs();
2239 }
2240 #endif
2241 if (cont_offset == 0) {
2242 // Let the normal error handling report the exception
2243 return NULL;
2244 }
2245 return code_begin() + cont_offset;
2246 }
2247
2248
2249
2250 void nmethod_init() {
2251 // make sure you didn't forget to adjust the filler fields
2252 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2253 }
2254
2255
2256 //-------------------------------------------------------------------------------------------
2257
2258
2259 // QQQ might we make this work from a frame??
2260 nmethodLocker::nmethodLocker(address pc) {
2261 CodeBlob* cb = CodeCache::find_blob(pc);
2262 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2263 _nm = (nmethod*)cb;
2264 lock_nmethod(_nm);
2265 }
2266
2267 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2268 // should pass zombie_ok == true.
2269 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2270 if (nm == NULL) return;
2271 Atomic::inc(&nm->_lock_count);
2272 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2273 }
2274
2275 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2276 if (nm == NULL) return;
2277 Atomic::dec(&nm->_lock_count);
2278 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2279 }
2280
2281
2282 // -----------------------------------------------------------------------------
2283 // nmethod::get_deopt_original_pc
2284 //
2285 // Return the original PC for the given PC if:
2286 // (a) the given PC belongs to a nmethod and
2287 // (b) it is a deopt PC
2288 address nmethod::get_deopt_original_pc(const frame* fr) {
2289 if (fr->cb() == NULL) return NULL;
2290
2291 nmethod* nm = fr->cb()->as_nmethod_or_null();
2292 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2293 return nm->get_original_pc(fr);
2294
2295 return NULL;
2296 }
2297
2298
2299 // -----------------------------------------------------------------------------
2300 // MethodHandle
2301
2302 bool nmethod::is_method_handle_return(address return_pc) {
2303 if (!has_method_handle_invokes()) return false;
2304 PcDesc* pd = pc_desc_at(return_pc);
2305 if (pd == NULL)
2306 return false;
2307 return pd->is_method_handle_invoke();
2308 }
2309
2310
2311 // -----------------------------------------------------------------------------
2312 // Verification
2313
2314 class VerifyOopsClosure: public OopClosure {
2315 nmethod* _nm;
2316 bool _ok;
2317 public:
2318 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2319 bool ok() { return _ok; }
2320 virtual void do_oop(oop* p) {
2321 if ((*p) == NULL || (*p)->is_oop()) return;
2322 if (_ok) {
2323 _nm->print_nmethod(true);
2324 _ok = false;
2325 }
2326 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2327 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2328 }
2329 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2330 };
2331
2332 void nmethod::verify() {
2333
2334 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2335 // seems odd.
2336
2337 if( is_zombie() || is_not_entrant() )
2338 return;
2339
2340 // Make sure all the entry points are correctly aligned for patching.
2341 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2342
2343 // assert(method()->is_oop(), "must be valid");
2344
2345 ResourceMark rm;
2346
2347 if (!CodeCache::contains(this)) {
2348 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2349 }
2350
2351 if(is_native_method() )
2352 return;
2353
2354 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2355 if (nm != this) {
2356 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2357 this));
2358 }
2359
2360 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2361 if (! p->verify(this)) {
2362 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2363 }
2364 }
2365
2366 VerifyOopsClosure voc(this);
2367 oops_do(&voc);
2368 assert(voc.ok(), "embedded oops must be OK");
2369 verify_scavenge_root_oops();
2370
2371 verify_scopes();
2372 }
2373
2374
2375 void nmethod::verify_interrupt_point(address call_site) {
2376 // This code does not work in release mode since
2377 // owns_lock only is available in debug mode.
2378 CompiledIC* ic = NULL;
2379 Thread *cur = Thread::current();
2380 if (CompiledIC_lock->owner() == cur ||
2381 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2382 SafepointSynchronize::is_at_safepoint())) {
2383 ic = CompiledIC_at(this, call_site);
2384 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2385 } else {
2386 MutexLocker ml_verify (CompiledIC_lock);
2387 ic = CompiledIC_at(this, call_site);
2388 }
2389 PcDesc* pd = pc_desc_at(ic->end_of_call());
2390 assert(pd != NULL, "PcDesc must exist");
2391 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2392 pd->obj_decode_offset(), pd->should_reexecute(),
2393 pd->return_oop());
2394 !sd->is_top(); sd = sd->sender()) {
2395 sd->verify();
2396 }
2397 }
2398
2399 void nmethod::verify_scopes() {
2400 if( !method() ) return; // Runtime stubs have no scope
2401 if (method()->is_native()) return; // Ignore stub methods.
2402 // iterate through all interrupt point
2403 // and verify the debug information is valid.
2404 RelocIterator iter((nmethod*)this);
2405 while (iter.next()) {
2406 address stub = NULL;
2407 switch (iter.type()) {
2408 case relocInfo::virtual_call_type:
2409 verify_interrupt_point(iter.addr());
2410 break;
2411 case relocInfo::opt_virtual_call_type:
2412 stub = iter.opt_virtual_call_reloc()->static_stub();
2413 verify_interrupt_point(iter.addr());
2414 break;
2415 case relocInfo::static_call_type:
2416 stub = iter.static_call_reloc()->static_stub();
2417 //verify_interrupt_point(iter.addr());
2418 break;
2419 case relocInfo::runtime_call_type:
2420 address destination = iter.reloc()->value();
2421 // Right now there is no way to find out which entries support
2422 // an interrupt point. It would be nice if we had this
2423 // information in a table.
2424 break;
2425 }
2426 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2427 }
2428 }
2429
2430
2431 // -----------------------------------------------------------------------------
2432 // Non-product code
2433 #ifndef PRODUCT
2434
2435 class DebugScavengeRoot: public OopClosure {
2436 nmethod* _nm;
2437 bool _ok;
2438 public:
2439 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2440 bool ok() { return _ok; }
2441 virtual void do_oop(oop* p) {
2442 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2443 if (_ok) {
2444 _nm->print_nmethod(true);
2445 _ok = false;
2446 }
2447 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2448 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2449 (*p)->print();
2450 }
2451 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2452 };
2453
2454 void nmethod::verify_scavenge_root_oops() {
2455 if (!on_scavenge_root_list()) {
2456 // Actually look inside, to verify the claim that it's clean.
2457 DebugScavengeRoot debug_scavenge_root(this);
2458 oops_do(&debug_scavenge_root);
2459 if (!debug_scavenge_root.ok())
2460 fatal("found an unadvertised bad scavengable oop in the code cache");
2461 }
2462 assert(scavenge_root_not_marked(), "");
2463 }
2464
2465 #endif // PRODUCT
2466
2467 // Printing operations
2468
2469 void nmethod::print() const {
2470 ResourceMark rm;
2471 ttyLocker ttyl; // keep the following output all in one block
2472
2473 tty->print("Compiled method ");
2474
2475 if (is_compiled_by_c1()) {
2476 tty->print("(c1) ");
2477 } else if (is_compiled_by_c2()) {
2478 tty->print("(c2) ");
2479 } else if (is_compiled_by_shark()) {
2480 tty->print("(shark) ");
2481 } else {
2482 tty->print("(nm) ");
2483 }
2484
2485 print_on(tty, NULL);
2486
2487 if (WizardMode) {
2488 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2489 tty->print(" for method " INTPTR_FORMAT , (address)method());
2490 tty->print(" { ");
2491 if (is_in_use()) tty->print("in_use ");
2492 if (is_not_entrant()) tty->print("not_entrant ");
2493 if (is_zombie()) tty->print("zombie ");
2494 if (is_unloaded()) tty->print("unloaded ");
2495 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2496 tty->print_cr("}:");
2497 }
2498 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2499 (address)this,
2500 (address)this + size(),
2501 size());
2502 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2503 relocation_begin(),
2504 relocation_end(),
2505 relocation_size());
2506 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2507 consts_begin(),
2508 consts_end(),
2509 consts_size());
2510 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2511 insts_begin(),
2512 insts_end(),
2513 insts_size());
2514 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2515 stub_begin(),
2516 stub_end(),
2517 stub_size());
2518 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2519 oops_begin(),
2520 oops_end(),
2521 oops_size());
2522 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2523 metadata_begin(),
2524 metadata_end(),
2525 metadata_size());
2526 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2527 scopes_data_begin(),
2528 scopes_data_end(),
2529 scopes_data_size());
2530 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2531 scopes_pcs_begin(),
2532 scopes_pcs_end(),
2533 scopes_pcs_size());
2534 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2535 dependencies_begin(),
2536 dependencies_end(),
2537 dependencies_size());
2538 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2539 handler_table_begin(),
2540 handler_table_end(),
2541 handler_table_size());
2542 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2543 nul_chk_table_begin(),
2544 nul_chk_table_end(),
2545 nul_chk_table_size());
2546 }
2547
2548 void nmethod::print_code() {
2549 HandleMark hm;
2550 ResourceMark m;
2551 Disassembler::decode(this);
2552 }
2553
2554
2555 #ifndef PRODUCT
2556
2557 void nmethod::print_scopes() {
2558 // Find the first pc desc for all scopes in the code and print it.
2559 ResourceMark rm;
2560 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2561 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2562 continue;
2563
2564 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2565 sd->print_on(tty, p);
2566 }
2567 }
2568
2569 void nmethod::print_dependencies() {
2570 ResourceMark rm;
2571 ttyLocker ttyl; // keep the following output all in one block
2572 tty->print_cr("Dependencies:");
2573 for (Dependencies::DepStream deps(this); deps.next(); ) {
2574 deps.print_dependency();
2575 Klass* ctxk = deps.context_type();
2576 if (ctxk != NULL) {
2577 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2578 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2579 }
2580 }
2581 deps.log_dependency(); // put it into the xml log also
2582 }
2583 }
2584
2585
2586 void nmethod::print_relocations() {
2587 ResourceMark m; // in case methods get printed via the debugger
2588 tty->print_cr("relocations:");
2589 RelocIterator iter(this);
2590 iter.print();
2591 if (UseRelocIndex) {
2592 jint* index_end = (jint*)relocation_end() - 1;
2593 jint index_size = *index_end;
2594 jint* index_start = (jint*)( (address)index_end - index_size );
2595 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2596 if (index_size > 0) {
2597 jint* ip;
2598 for (ip = index_start; ip+2 <= index_end; ip += 2)
2599 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2600 ip[0],
2601 ip[1],
2602 header_end()+ip[0],
2603 relocation_begin()-1+ip[1]);
2604 for (; ip < index_end; ip++)
2605 tty->print_cr(" (%d ?)", ip[0]);
2606 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip++);
2607 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2608 }
2609 }
2610 }
2611
2612
2613 void nmethod::print_pcs() {
2614 ResourceMark m; // in case methods get printed via debugger
2615 tty->print_cr("pc-bytecode offsets:");
2616 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2617 p->print(this);
2618 }
2619 }
2620
2621 #endif // PRODUCT
2622
2623 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2624 RelocIterator iter(this, begin, end);
2625 bool have_one = false;
2626 while (iter.next()) {
2627 have_one = true;
2628 switch (iter.type()) {
2629 case relocInfo::none: return "no_reloc";
2630 case relocInfo::oop_type: {
2631 stringStream st;
2632 oop_Relocation* r = iter.oop_reloc();
2633 oop obj = r->oop_value();
2634 st.print("oop(");
2635 if (obj == NULL) st.print("NULL");
2636 else obj->print_value_on(&st);
2637 st.print(")");
2638 return st.as_string();
2639 }
2640 case relocInfo::metadata_type: {
2641 stringStream st;
2642 metadata_Relocation* r = iter.metadata_reloc();
2643 Metadata* obj = r->metadata_value();
2644 st.print("metadata(");
2645 if (obj == NULL) st.print("NULL");
2646 else obj->print_value_on(&st);
2647 st.print(")");
2648 return st.as_string();
2649 }
2650 case relocInfo::virtual_call_type: return "virtual_call";
2651 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2652 case relocInfo::static_call_type: return "static_call";
2653 case relocInfo::static_stub_type: return "static_stub";
2654 case relocInfo::runtime_call_type: return "runtime_call";
2655 case relocInfo::external_word_type: return "external_word";
2656 case relocInfo::internal_word_type: return "internal_word";
2657 case relocInfo::section_word_type: return "section_word";
2658 case relocInfo::poll_type: return "poll";
2659 case relocInfo::poll_return_type: return "poll_return";
2660 case relocInfo::type_mask: return "type_bit_mask";
2661 }
2662 }
2663 return have_one ? "other" : NULL;
2664 }
2665
2666 // Return a the last scope in (begin..end]
2667 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2668 PcDesc* p = pc_desc_near(begin+1);
2669 if (p != NULL && p->real_pc(this) <= end) {
2670 return new ScopeDesc(this, p->scope_decode_offset(),
2671 p->obj_decode_offset(), p->should_reexecute(),
2672 p->return_oop());
2673 }
2674 return NULL;
2675 }
2676
2677 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2678 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2679 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2680 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2681 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2682 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2683
2684 if (has_method_handle_invokes())
2685 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
2686
2687 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
2688
2689 if (block_begin == entry_point()) {
2690 methodHandle m = method();
2691 if (m.not_null()) {
2692 stream->print(" # ");
2693 m->print_value_on(stream);
2694 stream->cr();
2695 }
2696 if (m.not_null() && !is_osr_method()) {
2697 ResourceMark rm;
2698 int sizeargs = m->size_of_parameters();
2699 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2700 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2701 {
2702 int sig_index = 0;
2703 if (!m->is_static())
2704 sig_bt[sig_index++] = T_OBJECT; // 'this'
2705 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2706 BasicType t = ss.type();
2707 sig_bt[sig_index++] = t;
2708 if (type2size[t] == 2) {
2709 sig_bt[sig_index++] = T_VOID;
2710 } else {
2711 assert(type2size[t] == 1, "size is 1 or 2");
2712 }
2713 }
2714 assert(sig_index == sizeargs, "");
2715 }
2716 const char* spname = "sp"; // make arch-specific?
2717 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2718 int stack_slot_offset = this->frame_size() * wordSize;
2719 int tab1 = 14, tab2 = 24;
2720 int sig_index = 0;
2721 int arg_index = (m->is_static() ? 0 : -1);
2722 bool did_old_sp = false;
2723 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2724 bool at_this = (arg_index == -1);
2725 bool at_old_sp = false;
2726 BasicType t = (at_this ? T_OBJECT : ss.type());
2727 assert(t == sig_bt[sig_index], "sigs in sync");
2728 if (at_this)
2729 stream->print(" # this: ");
2730 else
2731 stream->print(" # parm%d: ", arg_index);
2732 stream->move_to(tab1);
2733 VMReg fst = regs[sig_index].first();
2734 VMReg snd = regs[sig_index].second();
2735 if (fst->is_reg()) {
2736 stream->print("%s", fst->name());
2737 if (snd->is_valid()) {
2738 stream->print(":%s", snd->name());
2739 }
2740 } else if (fst->is_stack()) {
2741 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2742 if (offset == stack_slot_offset) at_old_sp = true;
2743 stream->print("[%s+0x%x]", spname, offset);
2744 } else {
2745 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2746 }
2747 stream->print(" ");
2748 stream->move_to(tab2);
2749 stream->print("= ");
2750 if (at_this) {
2751 m->method_holder()->print_value_on(stream);
2752 } else {
2753 bool did_name = false;
2754 if (!at_this && ss.is_object()) {
2755 Symbol* name = ss.as_symbol_or_null();
2756 if (name != NULL) {
2757 name->print_value_on(stream);
2758 did_name = true;
2759 }
2760 }
2761 if (!did_name)
2762 stream->print("%s", type2name(t));
2763 }
2764 if (at_old_sp) {
2765 stream->print(" (%s of caller)", spname);
2766 did_old_sp = true;
2767 }
2768 stream->cr();
2769 sig_index += type2size[t];
2770 arg_index += 1;
2771 if (!at_this) ss.next();
2772 }
2773 if (!did_old_sp) {
2774 stream->print(" # ");
2775 stream->move_to(tab1);
2776 stream->print("[%s+0x%x]", spname, stack_slot_offset);
2777 stream->print(" (%s of caller)", spname);
2778 stream->cr();
2779 }
2780 }
2781 }
2782 }
2783
2784 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2785 // First, find an oopmap in (begin, end].
2786 // We use the odd half-closed interval so that oop maps and scope descs
2787 // which are tied to the byte after a call are printed with the call itself.
2788 address base = code_begin();
2789 OopMapSet* oms = oop_maps();
2790 if (oms != NULL) {
2791 for (int i = 0, imax = oms->size(); i < imax; i++) {
2792 OopMap* om = oms->at(i);
2793 address pc = base + om->offset();
2794 if (pc > begin) {
2795 if (pc <= end) {
2796 st->move_to(column);
2797 st->print("; ");
2798 om->print_on(st);
2799 }
2800 break;
2801 }
2802 }
2803 }
2804
2805 // Print any debug info present at this pc.
2806 ScopeDesc* sd = scope_desc_in(begin, end);
2807 if (sd != NULL) {
2808 st->move_to(column);
2809 if (sd->bci() == SynchronizationEntryBCI) {
2810 st->print(";*synchronization entry");
2811 } else {
2812 if (sd->method() == NULL) {
2813 st->print("method is NULL");
2814 } else if (sd->method()->is_native()) {
2815 st->print("method is native");
2816 } else {
2817 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2818 st->print(";*%s", Bytecodes::name(bc));
2819 switch (bc) {
2820 case Bytecodes::_invokevirtual:
2821 case Bytecodes::_invokespecial:
2822 case Bytecodes::_invokestatic:
2823 case Bytecodes::_invokeinterface:
2824 {
2825 Bytecode_invoke invoke(sd->method(), sd->bci());
2826 st->print(" ");
2827 if (invoke.name() != NULL)
2828 invoke.name()->print_symbol_on(st);
2829 else
2830 st->print("<UNKNOWN>");
2831 break;
2832 }
2833 case Bytecodes::_getfield:
2834 case Bytecodes::_putfield:
2835 case Bytecodes::_getstatic:
2836 case Bytecodes::_putstatic:
2837 {
2838 Bytecode_field field(sd->method(), sd->bci());
2839 st->print(" ");
2840 if (field.name() != NULL)
2841 field.name()->print_symbol_on(st);
2842 else
2843 st->print("<UNKNOWN>");
2844 }
2845 }
2846 }
2847 }
2848
2849 // Print all scopes
2850 for (;sd != NULL; sd = sd->sender()) {
2851 st->move_to(column);
2852 st->print("; -");
2853 if (sd->method() == NULL) {
2854 st->print("method is NULL");
2855 } else {
2856 sd->method()->print_short_name(st);
2857 }
2858 int lineno = sd->method()->line_number_from_bci(sd->bci());
2859 if (lineno != -1) {
2860 st->print("@%d (line %d)", sd->bci(), lineno);
2861 } else {
2862 st->print("@%d", sd->bci());
2863 }
2864 st->cr();
2865 }
2866 }
2867
2868 // Print relocation information
2869 const char* str = reloc_string_for(begin, end);
2870 if (str != NULL) {
2871 if (sd != NULL) st->cr();
2872 st->move_to(column);
2873 st->print("; {%s}", str);
2874 }
2875 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2876 if (cont_offset != 0) {
2877 st->move_to(column);
2878 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
2879 }
2880
2881 }
2882
2883 #ifndef PRODUCT
2884
2885 void nmethod::print_value_on(outputStream* st) const {
2886 st->print("nmethod");
2887 print_on(st, NULL);
2888 }
2889
2890 void nmethod::print_calls(outputStream* st) {
2891 RelocIterator iter(this);
2892 while (iter.next()) {
2893 switch (iter.type()) {
2894 case relocInfo::virtual_call_type:
2895 case relocInfo::opt_virtual_call_type: {
2896 VerifyMutexLocker mc(CompiledIC_lock);
2897 CompiledIC_at(iter.reloc())->print();
2898 break;
2899 }
2900 case relocInfo::static_call_type:
2901 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2902 compiledStaticCall_at(iter.reloc())->print();
2903 break;
2904 }
2905 }
2906 }
2907
2908 void nmethod::print_handler_table() {
2909 ExceptionHandlerTable(this).print();
2910 }
2911
2912 void nmethod::print_nul_chk_table() {
2913 ImplicitExceptionTable(this).print(code_begin());
2914 }
2915
2916 void nmethod::print_statistics() {
2917 ttyLocker ttyl;
2918 if (xtty != NULL) xtty->head("statistics type='nmethod'");
2919 nmethod_stats.print_native_nmethod_stats();
2920 nmethod_stats.print_nmethod_stats();
2921 DebugInformationRecorder::print_statistics();
2922 nmethod_stats.print_pc_stats();
2923 Dependencies::print_statistics();
2924 if (xtty != NULL) xtty->tail("statistics");
2925 }
2926
2927 #endif // PRODUCT