1 /*
2 * Copyright (c) 1997, 2013, 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) {
97 return false;
98 }
99 return compiler()->is_c1();
100 }
101 bool nmethod::is_compiled_by_c2() const {
102 if (compiler() == NULL) {
103 return false;
104 }
105 return compiler()->is_c2();
106 }
107 bool nmethod::is_compiled_by_shark() const {
108 if (compiler() == NULL) {
109 return false;
110 }
111 return compiler()->is_shark();
112 }
113
114
115
116 //---------------------------------------------------------------------------------
117 // NMethod statistics
118 // They are printed under various flags, including:
119 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
120 // (In the latter two cases, they like other stats are printed to the log only.)
121
122 #ifndef PRODUCT
123 // These variables are put into one block to reduce relocations
124 // and make it simpler to print from the debugger.
125 static
126 struct nmethod_stats_struct {
127 int nmethod_count;
128 int total_size;
129 int relocation_size;
130 int consts_size;
131 int insts_size;
132 int stub_size;
133 int scopes_data_size;
134 int scopes_pcs_size;
135 int dependencies_size;
136 int handler_table_size;
137 int nul_chk_table_size;
138 int oops_size;
139
140 void note_nmethod(nmethod* nm) {
141 nmethod_count += 1;
142 total_size += nm->size();
143 relocation_size += nm->relocation_size();
144 consts_size += nm->consts_size();
145 insts_size += nm->insts_size();
146 stub_size += nm->stub_size();
147 oops_size += nm->oops_size();
148 scopes_data_size += nm->scopes_data_size();
149 scopes_pcs_size += nm->scopes_pcs_size();
150 dependencies_size += nm->dependencies_size();
151 handler_table_size += nm->handler_table_size();
152 nul_chk_table_size += nm->nul_chk_table_size();
153 }
154 void print_nmethod_stats() {
155 if (nmethod_count == 0) return;
156 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
157 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
158 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
159 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
160 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size);
161 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
162 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
163 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
164 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
165 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
166 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
167 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
168 }
169
170 int native_nmethod_count;
171 int native_total_size;
172 int native_relocation_size;
173 int native_insts_size;
174 int native_oops_size;
175 void note_native_nmethod(nmethod* nm) {
176 native_nmethod_count += 1;
177 native_total_size += nm->size();
178 native_relocation_size += nm->relocation_size();
179 native_insts_size += nm->insts_size();
180 native_oops_size += nm->oops_size();
181 }
182 void print_native_nmethod_stats() {
183 if (native_nmethod_count == 0) return;
184 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
185 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
186 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
187 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size);
188 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
189 }
190
191 int pc_desc_resets; // number of resets (= number of caches)
192 int pc_desc_queries; // queries to nmethod::find_pc_desc
193 int pc_desc_approx; // number of those which have approximate true
194 int pc_desc_repeats; // number of _pc_descs[0] hits
195 int pc_desc_hits; // number of LRU cache hits
196 int pc_desc_tests; // total number of PcDesc examinations
197 int pc_desc_searches; // total number of quasi-binary search steps
198 int pc_desc_adds; // number of LUR cache insertions
199
200 void print_pc_stats() {
201 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
202 pc_desc_queries,
203 (double)(pc_desc_tests + pc_desc_searches)
204 / pc_desc_queries);
205 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
206 pc_desc_resets,
207 pc_desc_queries, pc_desc_approx,
208 pc_desc_repeats, pc_desc_hits,
209 pc_desc_tests, pc_desc_searches, pc_desc_adds);
210 }
211 } nmethod_stats;
212 #endif //PRODUCT
213
214
215 //---------------------------------------------------------------------------------
216
217
218 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
219 assert(pc != NULL, "Must be non null");
220 assert(exception.not_null(), "Must be non null");
221 assert(handler != NULL, "Must be non null");
222
223 _count = 0;
224 _exception_type = exception->klass();
225 _next = NULL;
226
227 add_address_and_handler(pc,handler);
228 }
229
230
231 address ExceptionCache::match(Handle exception, address pc) {
232 assert(pc != NULL,"Must be non null");
233 assert(exception.not_null(),"Must be non null");
234 if (exception->klass() == exception_type()) {
235 return (test_address(pc));
236 }
237
238 return NULL;
239 }
240
241
242 bool ExceptionCache::match_exception_with_space(Handle exception) {
243 assert(exception.not_null(),"Must be non null");
244 if (exception->klass() == exception_type() && count() < cache_size) {
245 return true;
246 }
247 return false;
248 }
249
250
251 address ExceptionCache::test_address(address addr) {
252 for (int i=0; i<count(); i++) {
253 if (pc_at(i) == addr) {
254 return handler_at(i);
255 }
256 }
257 return NULL;
258 }
259
260
261 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
262 if (test_address(addr) == handler) return true;
263 if (count() < cache_size) {
264 set_pc_at(count(),addr);
265 set_handler_at(count(), handler);
266 increment_count();
267 return true;
268 }
269 return false;
270 }
271
272
273 // private method for handling exception cache
274 // These methods are private, and used to manipulate the exception cache
275 // directly.
276 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
277 ExceptionCache* ec = exception_cache();
278 while (ec != NULL) {
279 if (ec->match_exception_with_space(exception)) {
280 return ec;
281 }
282 ec = ec->next();
283 }
284 return NULL;
285 }
286
287
288 //-----------------------------------------------------------------------------
289
290
291 // Helper used by both find_pc_desc methods.
292 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
293 NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
294 if (!approximate)
295 return pc->pc_offset() == pc_offset;
296 else
297 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
298 }
299
300 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
301 if (initial_pc_desc == NULL) {
302 _pc_descs[0] = NULL; // native method; no PcDescs at all
303 return;
304 }
305 NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
306 // reset the cache by filling it with benign (non-null) values
307 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
308 for (int i = 0; i < cache_size; i++)
309 _pc_descs[i] = initial_pc_desc;
310 }
311
312 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
313 NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
314 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
315
316 // Note: one might think that caching the most recently
317 // read value separately would be a win, but one would be
318 // wrong. When many threads are updating it, the cache
319 // line it's in would bounce between caches, negating
320 // any benefit.
321
322 // In order to prevent race conditions do not load cache elements
323 // repeatedly, but use a local copy:
324 PcDesc* res;
325
326 // Step one: Check the most recently added value.
327 res = _pc_descs[0];
328 if (res == NULL) return NULL; // native method; no PcDescs at all
329 if (match_desc(res, pc_offset, approximate)) {
330 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
331 return res;
332 }
333
334 // Step two: Check the rest of the LRU cache.
335 for (int i = 1; i < cache_size; ++i) {
336 res = _pc_descs[i];
337 if (res->pc_offset() < 0) break; // optimization: skip empty cache
338 if (match_desc(res, pc_offset, approximate)) {
339 NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
340 return res;
341 }
342 }
343
344 // Report failure.
345 return NULL;
346 }
347
348 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
349 NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
350 // Update the LRU cache by shifting pc_desc forward.
351 for (int i = 0; i < cache_size; i++) {
352 PcDesc* next = _pc_descs[i];
353 _pc_descs[i] = pc_desc;
354 pc_desc = next;
355 }
356 }
357
358 // adjust pcs_size so that it is a multiple of both oopSize and
359 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
360 // of oopSize, then 2*sizeof(PcDesc) is)
361 static int adjust_pcs_size(int pcs_size) {
362 int nsize = round_to(pcs_size, oopSize);
363 if ((nsize % sizeof(PcDesc)) != 0) {
364 nsize = pcs_size + sizeof(PcDesc);
365 }
366 assert((nsize % oopSize) == 0, "correct alignment");
367 return nsize;
368 }
369
370 //-----------------------------------------------------------------------------
371
372
373 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
374 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
375 assert(new_entry != NULL,"Must be non null");
376 assert(new_entry->next() == NULL, "Must be null");
377
378 if (exception_cache() != NULL) {
379 new_entry->set_next(exception_cache());
380 }
381 set_exception_cache(new_entry);
382 }
383
384 void nmethod::remove_from_exception_cache(ExceptionCache* ec) {
385 ExceptionCache* prev = NULL;
386 ExceptionCache* curr = exception_cache();
387 assert(curr != NULL, "nothing to remove");
388 // find the previous and next entry of ec
389 while (curr != ec) {
390 prev = curr;
391 curr = curr->next();
392 assert(curr != NULL, "ExceptionCache not found");
393 }
394 // now: curr == ec
395 ExceptionCache* next = curr->next();
396 if (prev == NULL) {
397 set_exception_cache(next);
398 } else {
399 prev->set_next(next);
400 }
401 delete curr;
402 }
403
404
405 // public method for accessing the exception cache
406 // These are the public access methods.
407 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
408 // We never grab a lock to read the exception cache, so we may
409 // have false negatives. This is okay, as it can only happen during
410 // the first few exception lookups for a given nmethod.
411 ExceptionCache* ec = exception_cache();
412 while (ec != NULL) {
413 address ret_val;
414 if ((ret_val = ec->match(exception,pc)) != NULL) {
415 return ret_val;
416 }
417 ec = ec->next();
418 }
419 return NULL;
420 }
421
422
423 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
424 // There are potential race conditions during exception cache updates, so we
425 // must own the ExceptionCache_lock before doing ANY modifications. Because
426 // we don't lock during reads, it is possible to have several threads attempt
427 // to update the cache with the same data. We need to check for already inserted
428 // copies of the current data before adding it.
429
430 MutexLocker ml(ExceptionCache_lock);
431 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
432
433 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
434 target_entry = new ExceptionCache(exception,pc,handler);
435 add_exception_cache_entry(target_entry);
436 }
437 }
438
439
440 //-------------end of code for ExceptionCache--------------
441
442
443 int nmethod::total_size() const {
444 return
445 consts_size() +
446 insts_size() +
447 stub_size() +
448 scopes_data_size() +
449 scopes_pcs_size() +
450 handler_table_size() +
451 nul_chk_table_size();
452 }
453
454 const char* nmethod::compile_kind() const {
455 if (is_osr_method()) return "osr";
456 if (method() != NULL && is_native_method()) return "c2n";
457 return NULL;
458 }
459
460 // Fill in default values for various flag fields
461 void nmethod::init_defaults() {
462 _state = in_use;
463 _marked_for_reclamation = 0;
464 _has_flushed_dependencies = 0;
465 _has_unsafe_access = 0;
466 _has_method_handle_invokes = 0;
467 _lazy_critical_native = 0;
468 _has_wide_vectors = 0;
469 _marked_for_deoptimization = 0;
470 _lock_count = 0;
471 _stack_traversal_mark = 0;
472 _unload_reported = false; // jvmti state
473
474 #ifdef ASSERT
475 _oops_are_stale = false;
476 #endif
477
478 _oops_do_mark_link = NULL;
479 _jmethod_id = NULL;
480 _osr_link = NULL;
481 _scavenge_root_link = NULL;
482 _scavenge_root_state = 0;
483 _compiler = NULL;
484
485 #ifdef HAVE_DTRACE_H
486 _trap_offset = 0;
487 #endif // def HAVE_DTRACE_H
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 CodeOffsets offsets;
506 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
507 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
508 nm = new (native_nmethod_size) nmethod(method(), native_nmethod_size,
509 compile_id, &offsets,
510 code_buffer, frame_size,
511 basic_lock_owner_sp_offset,
512 basic_lock_sp_offset, oop_maps);
513 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm));
514 if (PrintAssembly && nm != NULL) {
515 Disassembler::decode(nm);
516 }
517 }
518 // verify nmethod
519 debug_only(if (nm) nm->verify();) // might block
520
521 if (nm != NULL) {
522 nm->log_new_nmethod();
523 }
524
525 return nm;
526 }
527
528 #ifdef HAVE_DTRACE_H
529 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
530 CodeBuffer *code_buffer,
531 int vep_offset,
532 int trap_offset,
533 int frame_complete,
534 int frame_size) {
535 code_buffer->finalize_oop_references(method);
536 // create nmethod
537 nmethod* nm = NULL;
538 {
539 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
540 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
541 CodeOffsets offsets;
542 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
543 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
544 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
545
546 nm = new (nmethod_size) nmethod(method(), nmethod_size,
547 &offsets, code_buffer, frame_size);
548
549 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
550 if (PrintAssembly && nm != NULL) {
551 Disassembler::decode(nm);
552 }
553 }
554 // verify nmethod
555 debug_only(if (nm) nm->verify();) // might block
556
557 if (nm != NULL) {
558 nm->log_new_nmethod();
559 }
560
561 return nm;
562 }
563
564 #endif // def HAVE_DTRACE_H
565
566 nmethod* nmethod::new_nmethod(methodHandle method,
567 int compile_id,
568 int entry_bci,
569 CodeOffsets* offsets,
570 int orig_pc_offset,
571 DebugInformationRecorder* debug_info,
572 Dependencies* dependencies,
573 CodeBuffer* code_buffer, int frame_size,
574 OopMapSet* oop_maps,
575 ExceptionHandlerTable* handler_table,
576 ImplicitExceptionTable* nul_chk_table,
577 AbstractCompiler* compiler,
578 int comp_level
579 )
580 {
581 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
582 code_buffer->finalize_oop_references(method);
583 // create nmethod
584 nmethod* nm = NULL;
585 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
586 int nmethod_size =
587 allocation_size(code_buffer, sizeof(nmethod))
588 + adjust_pcs_size(debug_info->pcs_size())
589 + round_to(dependencies->size_in_bytes() , oopSize)
590 + round_to(handler_table->size_in_bytes(), oopSize)
591 + round_to(nul_chk_table->size_in_bytes(), oopSize)
592 + round_to(debug_info->data_size() , oopSize);
593
594 nm = new (nmethod_size)
595 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
596 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
597 oop_maps,
598 handler_table,
599 nul_chk_table,
600 compiler,
601 comp_level);
602
603 if (nm != NULL) {
604 // To make dependency checking during class loading fast, record
605 // the nmethod dependencies in the classes it is dependent on.
606 // This allows the dependency checking code to simply walk the
607 // class hierarchy above the loaded class, checking only nmethods
608 // which are dependent on those classes. The slow way is to
609 // check every nmethod for dependencies which makes it linear in
610 // the number of methods compiled. For applications with a lot
611 // classes the slow way is too slow.
612 for (Dependencies::DepStream deps(nm); deps.next(); ) {
613 Klass* klass = deps.context_type();
614 if (klass == NULL) {
615 continue; // ignore things like evol_method
616 }
617
618 // record this nmethod as dependent on this klass
619 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
620 }
621 NOT_PRODUCT(nmethod_stats.note_nmethod(nm));
622 if (PrintAssembly) {
623 Disassembler::decode(nm);
624 }
625 }
626 }
627 // Do verification and logging outside CodeCache_lock.
628 if (nm != NULL) {
629 // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
630 DEBUG_ONLY(nm->verify();)
631 nm->log_new_nmethod();
632 }
633 return nm;
634 }
635
636
637 // For native wrappers
638 nmethod::nmethod(
639 Method* method,
640 int nmethod_size,
641 int compile_id,
642 CodeOffsets* offsets,
643 CodeBuffer* code_buffer,
644 int frame_size,
645 ByteSize basic_lock_owner_sp_offset,
646 ByteSize basic_lock_sp_offset,
647 OopMapSet* oop_maps )
648 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
649 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
650 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
651 _native_basic_lock_sp_offset(basic_lock_sp_offset)
652 {
653 {
654 debug_only(No_Safepoint_Verifier nsv;)
655 assert_locked_or_safepoint(CodeCache_lock);
656
657 init_defaults();
658 _method = method;
659 _entry_bci = InvocationEntryBci;
660 // We have no exception handler or deopt handler make the
661 // values something that will never match a pc like the nmethod vtable entry
662 _exception_offset = 0;
663 _deoptimize_offset = 0;
664 _deoptimize_mh_offset = 0;
665 _orig_pc_offset = 0;
666
667 _consts_offset = data_offset();
668 _stub_offset = data_offset();
669 _oops_offset = data_offset();
670 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
671 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
672 _scopes_pcs_offset = _scopes_data_offset;
673 _dependencies_offset = _scopes_pcs_offset;
674 _handler_table_offset = _dependencies_offset;
675 _nul_chk_table_offset = _handler_table_offset;
676 _nmethod_end_offset = _nul_chk_table_offset;
677 _compile_id = compile_id;
678 _comp_level = CompLevel_none;
679 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
680 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
681 _osr_entry_point = NULL;
682 _exception_cache = NULL;
683 _pc_desc_cache.reset_to(NULL);
684 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
685
686 code_buffer->copy_values_to(this);
687 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
688 CodeCache::add_scavenge_root_nmethod(this);
689 Universe::heap()->register_nmethod(this);
690 }
691 debug_only(verify_scavenge_root_oops());
692 CodeCache::commit(this);
693 }
694
695 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
696 ttyLocker ttyl; // keep the following output all in one block
697 // This output goes directly to the tty, not the compiler log.
698 // To enable tools to match it up with the compilation activity,
699 // be sure to tag this tty output with the compile ID.
700 if (xtty != NULL) {
701 xtty->begin_head("print_native_nmethod");
702 xtty->method(_method);
703 xtty->stamp();
704 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
705 }
706 // print the header part first
707 print();
708 // then print the requested information
709 if (PrintNativeNMethods) {
710 print_code();
711 if (oop_maps != NULL) {
712 oop_maps->print();
713 }
714 }
715 if (PrintRelocations) {
716 print_relocations();
717 }
718 if (xtty != NULL) {
719 xtty->tail("print_native_nmethod");
720 }
721 }
722 }
723
724 // For dtrace wrappers
725 #ifdef HAVE_DTRACE_H
726 nmethod::nmethod(
727 Method* method,
728 int nmethod_size,
729 CodeOffsets* offsets,
730 CodeBuffer* code_buffer,
731 int frame_size)
732 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
733 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
734 _native_receiver_sp_offset(in_ByteSize(-1)),
735 _native_basic_lock_sp_offset(in_ByteSize(-1))
736 {
737 {
738 debug_only(No_Safepoint_Verifier nsv;)
739 assert_locked_or_safepoint(CodeCache_lock);
740
741 init_defaults();
742 _method = method;
743 _entry_bci = InvocationEntryBci;
744 // We have no exception handler or deopt handler make the
745 // values something that will never match a pc like the nmethod vtable entry
746 _exception_offset = 0;
747 _deoptimize_offset = 0;
748 _deoptimize_mh_offset = 0;
749 _unwind_handler_offset = -1;
750 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
751 _orig_pc_offset = 0;
752 _consts_offset = data_offset();
753 _stub_offset = data_offset();
754 _oops_offset = data_offset();
755 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
756 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
757 _scopes_pcs_offset = _scopes_data_offset;
758 _dependencies_offset = _scopes_pcs_offset;
759 _handler_table_offset = _dependencies_offset;
760 _nul_chk_table_offset = _handler_table_offset;
761 _nmethod_end_offset = _nul_chk_table_offset;
762 _compile_id = 0; // default
763 _comp_level = CompLevel_none;
764 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
765 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
766 _osr_entry_point = NULL;
767 _exception_cache = NULL;
768 _pc_desc_cache.reset_to(NULL);
769 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
770
771 code_buffer->copy_values_to(this);
772 debug_only(verify_scavenge_root_oops());
773 CodeCache::commit(this);
774 }
775
776 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
777 ttyLocker ttyl; // keep the following output all in one block
778 // This output goes directly to the tty, not the compiler log.
779 // To enable tools to match it up with the compilation activity,
780 // be sure to tag this tty output with the compile ID.
781 if (xtty != NULL) {
782 xtty->begin_head("print_dtrace_nmethod");
783 xtty->method(_method);
784 xtty->stamp();
785 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
786 }
787 // print the header part first
788 print();
789 // then print the requested information
790 if (PrintNMethods) {
791 print_code();
792 }
793 if (PrintRelocations) {
794 print_relocations();
795 }
796 if (xtty != NULL) {
797 xtty->tail("print_dtrace_nmethod");
798 }
799 }
800 }
801 #endif // def HAVE_DTRACE_H
802
803 void* nmethod::operator new(size_t size, int nmethod_size) throw() {
804 // Not critical, may return null if there is too little continuous memory
805 return CodeCache::allocate(nmethod_size);
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 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
843
844 // Section offsets
845 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
846 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
847
848 // Exception handler and deopt handler are in the stub section
849 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
850 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
851 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
852 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
853 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
854 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
855 } else {
856 _deoptimize_mh_offset = -1;
857 }
858 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
859 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
860 } else {
861 _unwind_handler_offset = -1;
862 }
863
864 _oops_offset = data_offset();
865 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
866 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
867
868 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
869 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
870 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
871 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
872 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
873
874 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
875 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
876 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
877 _exception_cache = NULL;
878 _pc_desc_cache.reset_to(scopes_pcs_begin());
879
880 // Copy contents of ScopeDescRecorder to nmethod
881 code_buffer->copy_values_to(this);
882 debug_info->copy_to(this);
883 dependencies->copy_to(this);
884 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
885 CodeCache::add_scavenge_root_nmethod(this);
886 Universe::heap()->register_nmethod(this);
887 }
888 debug_only(verify_scavenge_root_oops());
889
890 CodeCache::commit(this);
891
892 // Copy contents of ExceptionHandlerTable to nmethod
893 handler_table->copy_to(this);
894 nul_chk_table->copy_to(this);
895
896 // we use the information of entry points to find out if a method is
897 // static or non static
898 assert(compiler->is_c2() ||
899 _method->is_static() == (entry_point() == _verified_entry_point),
900 " entry points must be same for static methods and vice versa");
901 }
902
903 bool printnmethods = PrintNMethods
904 || CompilerOracle::should_print(_method)
905 || CompilerOracle::has_option_string(_method, "PrintNMethods");
906 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
907 print_nmethod(printnmethods);
908 }
909 }
910
911
912 // Print a short set of xml attributes to identify this nmethod. The
913 // output should be embedded in some other element.
914 void nmethod::log_identity(xmlStream* log) const {
915 log->print(" compile_id='%d'", compile_id());
916 const char* nm_kind = compile_kind();
917 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
918 if (compiler() != NULL) {
919 log->print(" compiler='%s'", compiler()->name());
920 }
921 if (TieredCompilation) {
922 log->print(" level='%d'", comp_level());
923 }
924 }
925
926
927 #define LOG_OFFSET(log, name) \
928 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
929 log->print(" " XSTR(name) "_offset='%d'" , \
930 (intptr_t)name##_begin() - (intptr_t)this)
931
932
933 void nmethod::log_new_nmethod() const {
934 if (LogCompilation && xtty != NULL) {
935 ttyLocker ttyl;
936 HandleMark hm;
937 xtty->begin_elem("nmethod");
938 log_identity(xtty);
939 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
940 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
941
942 LOG_OFFSET(xtty, relocation);
943 LOG_OFFSET(xtty, consts);
944 LOG_OFFSET(xtty, insts);
945 LOG_OFFSET(xtty, stub);
946 LOG_OFFSET(xtty, scopes_data);
947 LOG_OFFSET(xtty, scopes_pcs);
948 LOG_OFFSET(xtty, dependencies);
949 LOG_OFFSET(xtty, handler_table);
950 LOG_OFFSET(xtty, nul_chk_table);
951 LOG_OFFSET(xtty, oops);
952
953 xtty->method(method());
954 xtty->stamp();
955 xtty->end_elem();
956 }
957 }
958
959 #undef LOG_OFFSET
960
961
962 // Print out more verbose output usually for a newly created nmethod.
963 void nmethod::print_on(outputStream* st, const char* msg) const {
964 if (st != NULL) {
965 ttyLocker ttyl;
966 if (WizardMode) {
967 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
968 st->print_cr(" (" INTPTR_FORMAT ")", this);
969 } else {
970 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
971 }
972 }
973 }
974
975
976 void nmethod::print_nmethod(bool printmethod) {
977 ttyLocker ttyl; // keep the following output all in one block
978 if (xtty != NULL) {
979 xtty->begin_head("print_nmethod");
980 xtty->stamp();
981 xtty->end_head();
982 }
983 // print the header part first
984 print();
985 // then print the requested information
986 if (printmethod) {
987 print_code();
988 print_pcs();
989 if (oop_maps()) {
990 oop_maps()->print();
991 }
992 }
993 if (PrintDebugInfo) {
994 print_scopes();
995 }
996 if (PrintRelocations) {
997 print_relocations();
998 }
999 if (PrintDependencies) {
1000 print_dependencies();
1001 }
1002 if (PrintExceptionHandlers) {
1003 print_handler_table();
1004 print_nul_chk_table();
1005 }
1006 if (xtty != NULL) {
1007 xtty->tail("print_nmethod");
1008 }
1009 }
1010
1011
1012 // Promote one word from an assembly-time handle to a live embedded oop.
1013 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1014 if (handle == NULL ||
1015 // As a special case, IC oops are initialized to 1 or -1.
1016 handle == (jobject) Universe::non_oop_word()) {
1017 (*dest) = (oop) handle;
1018 } else {
1019 (*dest) = JNIHandles::resolve_non_null(handle);
1020 }
1021 }
1022
1023
1024 // Have to have the same name because it's called by a template
1025 void nmethod::copy_values(GrowableArray<jobject>* array) {
1026 int length = array->length();
1027 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1028 oop* dest = oops_begin();
1029 for (int index = 0 ; index < length; index++) {
1030 initialize_immediate_oop(&dest[index], array->at(index));
1031 }
1032
1033 // Now we can fix up all the oops in the code. We need to do this
1034 // in the code because the assembler uses jobjects as placeholders.
1035 // The code and relocations have already been initialized by the
1036 // CodeBlob constructor, so it is valid even at this early point to
1037 // iterate over relocations and patch the code.
1038 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1039 }
1040
1041 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1042 int length = array->length();
1043 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1044 Metadata** dest = metadata_begin();
1045 for (int index = 0 ; index < length; index++) {
1046 dest[index] = array->at(index);
1047 }
1048 }
1049
1050 bool nmethod::is_at_poll_return(address pc) {
1051 RelocIterator iter(this, pc, pc+1);
1052 while (iter.next()) {
1053 if (iter.type() == relocInfo::poll_return_type)
1054 return true;
1055 }
1056 return false;
1057 }
1058
1059
1060 bool nmethod::is_at_poll_or_poll_return(address pc) {
1061 RelocIterator iter(this, pc, pc+1);
1062 while (iter.next()) {
1063 relocInfo::relocType t = iter.type();
1064 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1065 return true;
1066 }
1067 return false;
1068 }
1069
1070
1071 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1072 // re-patch all oop-bearing instructions, just in case some oops moved
1073 RelocIterator iter(this, begin, end);
1074 while (iter.next()) {
1075 if (iter.type() == relocInfo::oop_type) {
1076 oop_Relocation* reloc = iter.oop_reloc();
1077 if (initialize_immediates && reloc->oop_is_immediate()) {
1078 oop* dest = reloc->oop_addr();
1079 initialize_immediate_oop(dest, (jobject) *dest);
1080 }
1081 // Refresh the oop-related bits of this instruction.
1082 reloc->fix_oop_relocation();
1083 } else if (iter.type() == relocInfo::metadata_type) {
1084 metadata_Relocation* reloc = iter.metadata_reloc();
1085 reloc->fix_metadata_relocation();
1086 }
1087 }
1088 }
1089
1090
1091 void nmethod::verify_oop_relocations() {
1092 // Ensure sure that the code matches the current oop values
1093 RelocIterator iter(this, NULL, NULL);
1094 while (iter.next()) {
1095 if (iter.type() == relocInfo::oop_type) {
1096 oop_Relocation* reloc = iter.oop_reloc();
1097 if (!reloc->oop_is_immediate()) {
1098 reloc->verify_oop_relocation();
1099 }
1100 }
1101 }
1102 }
1103
1104
1105 ScopeDesc* nmethod::scope_desc_at(address pc) {
1106 PcDesc* pd = pc_desc_at(pc);
1107 guarantee(pd != NULL, "scope must be present");
1108 return new ScopeDesc(this, pd->scope_decode_offset(),
1109 pd->obj_decode_offset(), pd->should_reexecute(),
1110 pd->return_oop());
1111 }
1112
1113
1114 void nmethod::clear_inline_caches() {
1115 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1116 if (is_zombie()) {
1117 return;
1118 }
1119
1120 RelocIterator iter(this);
1121 while (iter.next()) {
1122 iter.reloc()->clear_inline_cache();
1123 }
1124 }
1125
1126
1127 void nmethod::cleanup_inline_caches() {
1128
1129 assert_locked_or_safepoint(CompiledIC_lock);
1130
1131 // If the method is not entrant or zombie then a JMP is plastered over the
1132 // first few bytes. If an oop in the old code was there, that oop
1133 // should not get GC'd. Skip the first few bytes of oops on
1134 // not-entrant methods.
1135 address low_boundary = verified_entry_point();
1136 if (!is_in_use()) {
1137 low_boundary += NativeJump::instruction_size;
1138 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1139 // This means that the low_boundary is going to be a little too high.
1140 // This shouldn't matter, since oops of non-entrant methods are never used.
1141 // In fact, why are we bothering to look at oops in a non-entrant method??
1142 }
1143
1144 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1145 ResourceMark rm;
1146 RelocIterator iter(this, low_boundary);
1147 while(iter.next()) {
1148 switch(iter.type()) {
1149 case relocInfo::virtual_call_type:
1150 case relocInfo::opt_virtual_call_type: {
1151 CompiledIC *ic = CompiledIC_at(iter.reloc());
1152 // Ok, to lookup references to zombies here
1153 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1154 if( cb != NULL && cb->is_nmethod() ) {
1155 nmethod* nm = (nmethod*)cb;
1156 // Clean inline caches pointing to both zombie and not_entrant methods
1157 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1158 }
1159 break;
1160 }
1161 case relocInfo::static_call_type: {
1162 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1163 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1164 if( cb != NULL && cb->is_nmethod() ) {
1165 nmethod* nm = (nmethod*)cb;
1166 // Clean inline caches pointing to both zombie and not_entrant methods
1167 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1168 }
1169 break;
1170 }
1171 }
1172 }
1173 }
1174
1175 // This is a private interface with the sweeper.
1176 void nmethod::mark_as_seen_on_stack() {
1177 assert(is_alive(), "Must be an alive method");
1178 // Set the traversal mark to ensure that the sweeper does 2
1179 // cleaning passes before moving to zombie.
1180 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1181 }
1182
1183 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1184 // there are no activations on the stack, not in use by the VM,
1185 // and not in use by the ServiceThread)
1186 bool nmethod::can_not_entrant_be_converted() {
1187 assert(is_not_entrant(), "must be a non-entrant method");
1188
1189 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1190 // count can be greater than the stack traversal count before it hits the
1191 // nmethod for the second time.
1192 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1193 !is_locked_by_vm();
1194 }
1195
1196 void nmethod::inc_decompile_count() {
1197 if (!is_compiled_by_c2()) return;
1198 // Could be gated by ProfileTraps, but do not bother...
1199 Method* m = method();
1200 if (m == NULL) return;
1201 MethodData* mdo = m->method_data();
1202 if (mdo == NULL) return;
1203 // There is a benign race here. See comments in methodData.hpp.
1204 mdo->inc_decompile_count();
1205 }
1206
1207 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1208
1209 post_compiled_method_unload();
1210
1211 // Since this nmethod is being unloaded, make sure that dependencies
1212 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1213 // indicate that this work is being done during a GC.
1214 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1215 assert(is_alive != NULL, "Should be non-NULL");
1216 // A non-NULL is_alive closure indicates that this is being called during GC.
1217 flush_dependencies(is_alive);
1218
1219 // Break cycle between nmethod & method
1220 if (TraceClassUnloading && WizardMode) {
1221 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1222 " unloadable], Method*(" INTPTR_FORMAT
1223 "), cause(" INTPTR_FORMAT ")",
1224 this, (address)_method, (address)cause);
1225 if (!Universe::heap()->is_gc_active())
1226 cause->klass()->print();
1227 }
1228 // Unlink the osr method, so we do not look this up again
1229 if (is_osr_method()) {
1230 invalidate_osr_method();
1231 }
1232 // If _method is already NULL the Method* is about to be unloaded,
1233 // so we don't have to break the cycle. Note that it is possible to
1234 // have the Method* live here, in case we unload the nmethod because
1235 // it is pointing to some oop (other than the Method*) being unloaded.
1236 if (_method != NULL) {
1237 // OSR methods point to the Method*, but the Method* does not
1238 // point back!
1239 if (_method->code() == this) {
1240 _method->clear_code(); // Break a cycle
1241 }
1242 _method = NULL; // Clear the method of this dead nmethod
1243 }
1244 // Make the class unloaded - i.e., change state and notify sweeper
1245 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1246 if (is_in_use()) {
1247 // Transitioning directly from live to unloaded -- so
1248 // we need to force a cache clean-up; remember this
1249 // for later on.
1250 CodeCache::set_needs_cache_clean(true);
1251 }
1252 _state = unloaded;
1253
1254 // Log the unloading.
1255 log_state_change();
1256
1257 // The Method* is gone at this point
1258 assert(_method == NULL, "Tautology");
1259
1260 set_osr_link(NULL);
1261 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1262 NMethodSweeper::report_state_change(this);
1263 }
1264
1265 void nmethod::invalidate_osr_method() {
1266 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1267 // Remove from list of active nmethods
1268 if (method() != NULL)
1269 method()->method_holder()->remove_osr_nmethod(this);
1270 // Set entry as invalid
1271 _entry_bci = InvalidOSREntryBci;
1272 }
1273
1274 void nmethod::log_state_change() const {
1275 if (LogCompilation) {
1276 if (xtty != NULL) {
1277 ttyLocker ttyl; // keep the following output all in one block
1278 if (_state == unloaded) {
1279 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1280 os::current_thread_id());
1281 } else {
1282 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1283 os::current_thread_id(),
1284 (_state == zombie ? " zombie='1'" : ""));
1285 }
1286 log_identity(xtty);
1287 xtty->stamp();
1288 xtty->end_elem();
1289 }
1290 }
1291 if (PrintCompilation && _state != unloaded) {
1292 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1293 }
1294 }
1295
1296 /**
1297 * Common functionality for both make_not_entrant and make_zombie
1298 */
1299 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1300 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1301 assert(!is_zombie(), "should not already be a zombie");
1302
1303 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1304 nmethodLocker nml(this);
1305 methodHandle the_method(method());
1306 No_Safepoint_Verifier nsv;
1307
1308 // during patching, depending on the nmethod state we must notify the GC that
1309 // code has been unloaded, unregistering it. We cannot do this right while
1310 // holding the Patching_lock because we need to use the CodeCache_lock. This
1311 // would be prone to deadlocks.
1312 // This flag is used to remember whether we need to later lock and unregister.
1313 bool nmethod_needs_unregister = false;
1314
1315 {
1316 // invalidate osr nmethod before acquiring the patching lock since
1317 // they both acquire leaf locks and we don't want a deadlock.
1318 // This logic is equivalent to the logic below for patching the
1319 // verified entry point of regular methods.
1320 if (is_osr_method()) {
1321 // this effectively makes the osr nmethod not entrant
1322 invalidate_osr_method();
1323 }
1324
1325 // Enter critical section. Does not block for safepoint.
1326 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1327
1328 if (_state == state) {
1329 // another thread already performed this transition so nothing
1330 // to do, but return false to indicate this.
1331 return false;
1332 }
1333
1334 // The caller can be calling the method statically or through an inline
1335 // cache call.
1336 if (!is_osr_method() && !is_not_entrant()) {
1337 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1338 SharedRuntime::get_handle_wrong_method_stub());
1339 }
1340
1341 if (is_in_use()) {
1342 // It's a true state change, so mark the method as decompiled.
1343 // Do it only for transition from alive.
1344 inc_decompile_count();
1345 }
1346
1347 // If the state is becoming a zombie, signal to unregister the nmethod with
1348 // the heap.
1349 // This nmethod may have already been unloaded during a full GC.
1350 if ((state == zombie) && !is_unloaded()) {
1351 nmethod_needs_unregister = true;
1352 }
1353
1354 // Must happen before state change. Otherwise we have a race condition in
1355 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1356 // transition its state from 'not_entrant' to 'zombie' without having to wait
1357 // for stack scanning.
1358 if (state == not_entrant) {
1359 mark_as_seen_on_stack();
1360 OrderAccess::storestore();
1361 }
1362
1363 // Change state
1364 _state = state;
1365
1366 // Log the transition once
1367 log_state_change();
1368
1369 // Remove nmethod from method.
1370 // We need to check if both the _code and _from_compiled_code_entry_point
1371 // refer to this nmethod because there is a race in setting these two fields
1372 // in Method* as seen in bugid 4947125.
1373 // If the vep() points to the zombie nmethod, the memory for the nmethod
1374 // could be flushed and the compiler and vtable stubs could still call
1375 // through it.
1376 if (method() != NULL && (method()->code() == this ||
1377 method()->from_compiled_entry() == verified_entry_point())) {
1378 HandleMark hm;
1379 method()->clear_code();
1380 }
1381 } // leave critical region under Patching_lock
1382
1383 // When the nmethod becomes zombie it is no longer alive so the
1384 // dependencies must be flushed. nmethods in the not_entrant
1385 // state will be flushed later when the transition to zombie
1386 // happens or they get unloaded.
1387 if (state == zombie) {
1388 {
1389 // Flushing dependecies must be done before any possible
1390 // safepoint can sneak in, otherwise the oops used by the
1391 // dependency logic could have become stale.
1392 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1393 if (nmethod_needs_unregister) {
1394 Universe::heap()->unregister_nmethod(this);
1395 }
1396 flush_dependencies(NULL);
1397 }
1398
1399 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1400 // event and it hasn't already been reported for this nmethod then
1401 // report it now. The event may have been reported earilier if the GC
1402 // marked it for unloading). JvmtiDeferredEventQueue support means
1403 // we no longer go to a safepoint here.
1404 post_compiled_method_unload();
1405
1406 #ifdef ASSERT
1407 // It's no longer safe to access the oops section since zombie
1408 // nmethods aren't scanned for GC.
1409 _oops_are_stale = true;
1410 #endif
1411 // the Method may be reclaimed by class unloading now that the
1412 // nmethod is in zombie state
1413 set_method(NULL);
1414 } else {
1415 assert(state == not_entrant, "other cases may need to be handled differently");
1416 }
1417
1418 if (TraceCreateZombies) {
1419 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1420 }
1421
1422 NMethodSweeper::report_state_change(this);
1423 return true;
1424 }
1425
1426 void nmethod::flush() {
1427 // Note that there are no valid oops in the nmethod anymore.
1428 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1429 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1430
1431 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1432 assert_locked_or_safepoint(CodeCache_lock);
1433
1434 // completely deallocate this method
1435 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1436 if (PrintMethodFlushing) {
1437 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1438 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
1439 }
1440
1441 // We need to deallocate any ExceptionCache data.
1442 // Note that we do not need to grab the nmethod lock for this, it
1443 // better be thread safe if we're disposing of it!
1444 ExceptionCache* ec = exception_cache();
1445 set_exception_cache(NULL);
1446 while(ec != NULL) {
1447 ExceptionCache* next = ec->next();
1448 delete ec;
1449 ec = next;
1450 }
1451
1452 if (on_scavenge_root_list()) {
1453 CodeCache::drop_scavenge_root_nmethod(this);
1454 }
1455
1456 #ifdef SHARK
1457 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1458 #endif // SHARK
1459
1460 ((CodeBlob*)(this))->flush();
1461
1462 CodeCache::free(this);
1463 }
1464
1465
1466 //
1467 // Notify all classes this nmethod is dependent on that it is no
1468 // longer dependent. This should only be called in two situations.
1469 // First, when a nmethod transitions to a zombie all dependents need
1470 // to be clear. Since zombification happens at a safepoint there's no
1471 // synchronization issues. The second place is a little more tricky.
1472 // During phase 1 of mark sweep class unloading may happen and as a
1473 // result some nmethods may get unloaded. In this case the flushing
1474 // of dependencies must happen during phase 1 since after GC any
1475 // dependencies in the unloaded nmethod won't be updated, so
1476 // traversing the dependency information in unsafe. In that case this
1477 // function is called with a non-NULL argument and this function only
1478 // notifies instanceKlasses that are reachable
1479
1480 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1481 assert_locked_or_safepoint(CodeCache_lock);
1482 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1483 "is_alive is non-NULL if and only if we are called during GC");
1484 if (!has_flushed_dependencies()) {
1485 set_has_flushed_dependencies();
1486 for (Dependencies::DepStream deps(this); deps.next(); ) {
1487 Klass* klass = deps.context_type();
1488 if (klass == NULL) continue; // ignore things like evol_method
1489
1490 // During GC the is_alive closure is non-NULL, and is used to
1491 // determine liveness of dependees that need to be updated.
1492 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1493 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1494 }
1495 }
1496 }
1497 }
1498
1499
1500 // If this oop is not live, the nmethod can be unloaded.
1501 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1502 assert(root != NULL, "just checking");
1503 oop obj = *root;
1504 if (obj == NULL || is_alive->do_object_b(obj)) {
1505 return false;
1506 }
1507
1508 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1509 // simply because one of its constant oops has gone dead.
1510 // No actual classes need to be unloaded in order for this to occur.
1511 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1512 make_unloaded(is_alive, obj);
1513 return true;
1514 }
1515
1516 // ------------------------------------------------------------------
1517 // post_compiled_method_load_event
1518 // new method for install_code() path
1519 // Transfer information from compilation to jvmti
1520 void nmethod::post_compiled_method_load_event() {
1521
1522 Method* moop = method();
1523 #ifndef USDT2
1524 HS_DTRACE_PROBE8(hotspot, compiled__method__load,
1525 moop->klass_name()->bytes(),
1526 moop->klass_name()->utf8_length(),
1527 moop->name()->bytes(),
1528 moop->name()->utf8_length(),
1529 moop->signature()->bytes(),
1530 moop->signature()->utf8_length(),
1531 insts_begin(), insts_size());
1532 #else /* USDT2 */
1533 HOTSPOT_COMPILED_METHOD_LOAD(
1534 (char *) moop->klass_name()->bytes(),
1535 moop->klass_name()->utf8_length(),
1536 (char *) moop->name()->bytes(),
1537 moop->name()->utf8_length(),
1538 (char *) moop->signature()->bytes(),
1539 moop->signature()->utf8_length(),
1540 insts_begin(), insts_size());
1541 #endif /* USDT2 */
1542
1543 if (JvmtiExport::should_post_compiled_method_load() ||
1544 JvmtiExport::should_post_compiled_method_unload()) {
1545 get_and_cache_jmethod_id();
1546 }
1547
1548 if (JvmtiExport::should_post_compiled_method_load()) {
1549 // Let the Service thread (which is a real Java thread) post the event
1550 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1551 JvmtiDeferredEventQueue::enqueue(
1552 JvmtiDeferredEvent::compiled_method_load_event(this));
1553 }
1554 }
1555
1556 jmethodID nmethod::get_and_cache_jmethod_id() {
1557 if (_jmethod_id == NULL) {
1558 // Cache the jmethod_id since it can no longer be looked up once the
1559 // method itself has been marked for unloading.
1560 _jmethod_id = method()->jmethod_id();
1561 }
1562 return _jmethod_id;
1563 }
1564
1565 void nmethod::post_compiled_method_unload() {
1566 if (unload_reported()) {
1567 // During unloading we transition to unloaded and then to zombie
1568 // and the unloading is reported during the first transition.
1569 return;
1570 }
1571
1572 assert(_method != NULL && !is_unloaded(), "just checking");
1573 DTRACE_METHOD_UNLOAD_PROBE(method());
1574
1575 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1576 // post the event. Sometime later this nmethod will be made a zombie
1577 // by the sweeper but the Method* will not be valid at that point.
1578 // If the _jmethod_id is null then no load event was ever requested
1579 // so don't bother posting the unload. The main reason for this is
1580 // that the jmethodID is a weak reference to the Method* so if
1581 // it's being unloaded there's no way to look it up since the weak
1582 // ref will have been cleared.
1583 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1584 assert(!unload_reported(), "already unloaded");
1585 JvmtiDeferredEvent event =
1586 JvmtiDeferredEvent::compiled_method_unload_event(this,
1587 _jmethod_id, insts_begin());
1588 if (SafepointSynchronize::is_at_safepoint()) {
1589 // Don't want to take the queueing lock. Add it as pending and
1590 // it will get enqueued later.
1591 JvmtiDeferredEventQueue::add_pending_event(event);
1592 } else {
1593 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1594 JvmtiDeferredEventQueue::enqueue(event);
1595 }
1596 }
1597
1598 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1599 // any time. As the nmethod is being unloaded now we mark it has
1600 // having the unload event reported - this will ensure that we don't
1601 // attempt to report the event in the unlikely scenario where the
1602 // event is enabled at the time the nmethod is made a zombie.
1603 set_unload_reported();
1604 }
1605
1606 // This is called at the end of the strong tracing/marking phase of a
1607 // GC to unload an nmethod if it contains otherwise unreachable
1608 // oops.
1609
1610 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1611 // Make sure the oop's ready to receive visitors
1612 assert(!is_zombie() && !is_unloaded(),
1613 "should not call follow on zombie or unloaded nmethod");
1614
1615 // If the method is not entrant then a JMP is plastered over the
1616 // first few bytes. If an oop in the old code was there, that oop
1617 // should not get GC'd. Skip the first few bytes of oops on
1618 // not-entrant methods.
1619 address low_boundary = verified_entry_point();
1620 if (is_not_entrant()) {
1621 low_boundary += NativeJump::instruction_size;
1622 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1623 // (See comment above.)
1624 }
1625
1626 // The RedefineClasses() API can cause the class unloading invariant
1627 // to no longer be true. See jvmtiExport.hpp for details.
1628 // Also, leave a debugging breadcrumb in local flag.
1629 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1630 if (a_class_was_redefined) {
1631 // This set of the unloading_occurred flag is done before the
1632 // call to post_compiled_method_unload() so that the unloading
1633 // of this nmethod is reported.
1634 unloading_occurred = true;
1635 }
1636
1637 // Exception cache
1638 ExceptionCache* ec = exception_cache();
1639 while (ec != NULL) {
1640 Klass* ex_klass = ec->exception_type();
1641 ExceptionCache* next_ec = ec->next();
1642 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
1643 remove_from_exception_cache(ec);
1644 }
1645 ec = next_ec;
1646 }
1647
1648 // If class unloading occurred we first iterate over all inline caches and
1649 // clear ICs where the cached oop is referring to an unloaded klass or method.
1650 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1651 // iteration below.
1652 if (unloading_occurred) {
1653 RelocIterator iter(this, low_boundary);
1654 while(iter.next()) {
1655 if (iter.type() == relocInfo::virtual_call_type) {
1656 CompiledIC *ic = CompiledIC_at(iter.reloc());
1657 if (ic->is_icholder_call()) {
1658 // The only exception is compiledICHolder oops which may
1659 // yet be marked below. (We check this further below).
1660 CompiledICHolder* cichk_oop = ic->cached_icholder();
1661 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1662 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1663 continue;
1664 }
1665 } else {
1666 Metadata* ic_oop = ic->cached_metadata();
1667 if (ic_oop != NULL) {
1668 if (ic_oop->is_klass()) {
1669 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1670 continue;
1671 }
1672 } else if (ic_oop->is_method()) {
1673 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1674 continue;
1675 }
1676 } else {
1677 ShouldNotReachHere();
1678 }
1679 }
1680 }
1681 ic->set_to_clean();
1682 }
1683 }
1684 }
1685
1686 // Compiled code
1687 {
1688 RelocIterator iter(this, low_boundary);
1689 while (iter.next()) {
1690 if (iter.type() == relocInfo::oop_type) {
1691 oop_Relocation* r = iter.oop_reloc();
1692 // In this loop, we must only traverse those oops directly embedded in
1693 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1694 assert(1 == (r->oop_is_immediate()) +
1695 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1696 "oop must be found in exactly one place");
1697 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1698 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1699 return;
1700 }
1701 }
1702 }
1703 }
1704 }
1705
1706
1707 // Scopes
1708 for (oop* p = oops_begin(); p < oops_end(); p++) {
1709 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1710 if (can_unload(is_alive, p, unloading_occurred)) {
1711 return;
1712 }
1713 }
1714
1715 // Ensure that all metadata is still alive
1716 verify_metadata_loaders(low_boundary, is_alive);
1717 }
1718
1719 #ifdef ASSERT
1720
1721 class CheckClass : AllStatic {
1722 static BoolObjectClosure* _is_alive;
1723
1724 // Check class_loader is alive for this bit of metadata.
1725 static void check_class(Metadata* md) {
1726 Klass* klass = NULL;
1727 if (md->is_klass()) {
1728 klass = ((Klass*)md);
1729 } else if (md->is_method()) {
1730 klass = ((Method*)md)->method_holder();
1731 } else if (md->is_methodData()) {
1732 klass = ((MethodData*)md)->method()->method_holder();
1733 } else {
1734 md->print();
1735 ShouldNotReachHere();
1736 }
1737 assert(klass->is_loader_alive(_is_alive), "must be alive");
1738 }
1739 public:
1740 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
1741 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
1742 _is_alive = is_alive;
1743 nm->metadata_do(check_class);
1744 }
1745 };
1746
1747 // This is called during a safepoint so can use static data
1748 BoolObjectClosure* CheckClass::_is_alive = NULL;
1749 #endif // ASSERT
1750
1751
1752 // Processing of oop references should have been sufficient to keep
1753 // all strong references alive. Any weak references should have been
1754 // cleared as well. Visit all the metadata and ensure that it's
1755 // really alive.
1756 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
1757 #ifdef ASSERT
1758 RelocIterator iter(this, low_boundary);
1759 while (iter.next()) {
1760 // static_stub_Relocations may have dangling references to
1761 // Method*s so trim them out here. Otherwise it looks like
1762 // compiled code is maintaining a link to dead metadata.
1763 address static_call_addr = NULL;
1764 if (iter.type() == relocInfo::opt_virtual_call_type) {
1765 CompiledIC* cic = CompiledIC_at(iter.reloc());
1766 if (!cic->is_call_to_interpreted()) {
1767 static_call_addr = iter.addr();
1768 }
1769 } else if (iter.type() == relocInfo::static_call_type) {
1770 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
1771 if (!csc->is_call_to_interpreted()) {
1772 static_call_addr = iter.addr();
1773 }
1774 }
1775 if (static_call_addr != NULL) {
1776 RelocIterator sciter(this, low_boundary);
1777 while (sciter.next()) {
1778 if (sciter.type() == relocInfo::static_stub_type &&
1779 sciter.static_stub_reloc()->static_call() == static_call_addr) {
1780 sciter.static_stub_reloc()->clear_inline_cache();
1781 }
1782 }
1783 }
1784 }
1785 // Check that the metadata embedded in the nmethod is alive
1786 CheckClass::do_check_class(is_alive, this);
1787 #endif
1788 }
1789
1790
1791 // Iterate over metadata calling this function. Used by RedefineClasses
1792 void nmethod::metadata_do(void f(Metadata*)) {
1793 address low_boundary = verified_entry_point();
1794 if (is_not_entrant()) {
1795 low_boundary += NativeJump::instruction_size;
1796 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1797 // (See comment above.)
1798 }
1799 {
1800 // Visit all immediate references that are embedded in the instruction stream.
1801 RelocIterator iter(this, low_boundary);
1802 while (iter.next()) {
1803 if (iter.type() == relocInfo::metadata_type ) {
1804 metadata_Relocation* r = iter.metadata_reloc();
1805 // In this lmetadata, we must only follow those metadatas directly embedded in
1806 // the code. Other metadatas (oop_index>0) are seen as part of
1807 // the metadata section below.
1808 assert(1 == (r->metadata_is_immediate()) +
1809 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1810 "metadata must be found in exactly one place");
1811 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1812 Metadata* md = r->metadata_value();
1813 f(md);
1814 }
1815 } else if (iter.type() == relocInfo::virtual_call_type) {
1816 // Check compiledIC holders associated with this nmethod
1817 CompiledIC *ic = CompiledIC_at(iter.reloc());
1818 if (ic->is_icholder_call()) {
1819 CompiledICHolder* cichk = ic->cached_icholder();
1820 f(cichk->holder_method());
1821 f(cichk->holder_klass());
1822 } else {
1823 Metadata* ic_oop = ic->cached_metadata();
1824 if (ic_oop != NULL) {
1825 f(ic_oop);
1826 }
1827 }
1828 }
1829 }
1830 }
1831
1832 // Visit the metadata section
1833 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1834 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
1835 Metadata* md = *p;
1836 f(md);
1837 }
1838
1839 // Call function Method*, not embedded in these other places.
1840 if (_method != NULL) f(_method);
1841 }
1842
1843 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1844 // make sure the oops ready to receive visitors
1845 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1846 assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1847
1848 // If the method is not entrant or zombie then a JMP is plastered over the
1849 // first few bytes. If an oop in the old code was there, that oop
1850 // should not get GC'd. Skip the first few bytes of oops on
1851 // not-entrant methods.
1852 address low_boundary = verified_entry_point();
1853 if (is_not_entrant()) {
1854 low_boundary += NativeJump::instruction_size;
1855 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1856 // (See comment above.)
1857 }
1858
1859 RelocIterator iter(this, low_boundary);
1860
1861 while (iter.next()) {
1862 if (iter.type() == relocInfo::oop_type ) {
1863 oop_Relocation* r = iter.oop_reloc();
1864 // In this loop, we must only follow those oops directly embedded in
1865 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1866 assert(1 == (r->oop_is_immediate()) +
1867 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1868 "oop must be found in exactly one place");
1869 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1870 f->do_oop(r->oop_addr());
1871 }
1872 }
1873 }
1874
1875 // Scopes
1876 // This includes oop constants not inlined in the code stream.
1877 for (oop* p = oops_begin(); p < oops_end(); p++) {
1878 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1879 f->do_oop(p);
1880 }
1881 }
1882
1883 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1884
1885 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1886
1887 // An nmethod is "marked" if its _mark_link is set non-null.
1888 // Even if it is the end of the linked list, it will have a non-null link value,
1889 // as long as it is on the list.
1890 // This code must be MP safe, because it is used from parallel GC passes.
1891 bool nmethod::test_set_oops_do_mark() {
1892 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1893 nmethod* observed_mark_link = _oops_do_mark_link;
1894 if (observed_mark_link == NULL) {
1895 // Claim this nmethod for this thread to mark.
1896 observed_mark_link = (nmethod*)
1897 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1898 if (observed_mark_link == NULL) {
1899
1900 // Atomically append this nmethod (now claimed) to the head of the list:
1901 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1902 for (;;) {
1903 nmethod* required_mark_nmethods = observed_mark_nmethods;
1904 _oops_do_mark_link = required_mark_nmethods;
1905 observed_mark_nmethods = (nmethod*)
1906 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1907 if (observed_mark_nmethods == required_mark_nmethods)
1908 break;
1909 }
1910 // Mark was clear when we first saw this guy.
1911 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
1912 return false;
1913 }
1914 }
1915 // On fall through, another racing thread marked this nmethod before we did.
1916 return true;
1917 }
1918
1919 void nmethod::oops_do_marking_prologue() {
1920 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
1921 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1922 // We use cmpxchg_ptr instead of regular assignment here because the user
1923 // may fork a bunch of threads, and we need them all to see the same state.
1924 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1925 guarantee(observed == NULL, "no races in this sequential code");
1926 }
1927
1928 void nmethod::oops_do_marking_epilogue() {
1929 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1930 nmethod* cur = _oops_do_mark_nmethods;
1931 while (cur != NMETHOD_SENTINEL) {
1932 assert(cur != NULL, "not NULL-terminated");
1933 nmethod* next = cur->_oops_do_mark_link;
1934 cur->_oops_do_mark_link = NULL;
1935 cur->fix_oop_relocations();
1936 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
1937 cur = next;
1938 }
1939 void* required = _oops_do_mark_nmethods;
1940 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1941 guarantee(observed == required, "no races in this sequential code");
1942 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
1943 }
1944
1945 class DetectScavengeRoot: public OopClosure {
1946 bool _detected_scavenge_root;
1947 public:
1948 DetectScavengeRoot() : _detected_scavenge_root(false)
1949 { NOT_PRODUCT(_print_nm = NULL); }
1950 bool detected_scavenge_root() { return _detected_scavenge_root; }
1951 virtual void do_oop(oop* p) {
1952 if ((*p) != NULL && (*p)->is_scavengable()) {
1953 NOT_PRODUCT(maybe_print(p));
1954 _detected_scavenge_root = true;
1955 }
1956 }
1957 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1958
1959 #ifndef PRODUCT
1960 nmethod* _print_nm;
1961 void maybe_print(oop* p) {
1962 if (_print_nm == NULL) return;
1963 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
1964 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
1965 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
1966 (void *)(*p), (intptr_t)p);
1967 (*p)->print();
1968 }
1969 #endif //PRODUCT
1970 };
1971
1972 bool nmethod::detect_scavenge_root_oops() {
1973 DetectScavengeRoot detect_scavenge_root;
1974 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
1975 oops_do(&detect_scavenge_root);
1976 return detect_scavenge_root.detected_scavenge_root();
1977 }
1978
1979 // Method that knows how to preserve outgoing arguments at call. This method must be
1980 // called with a frame corresponding to a Java invoke
1981 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1982 #ifndef SHARK
1983 if (!method()->is_native()) {
1984 SimpleScopeDesc ssd(this, fr.pc());
1985 Bytecode_invoke call(ssd.method(), ssd.bci());
1986 bool has_receiver = call.has_receiver();
1987 bool has_appendix = call.has_appendix();
1988 Symbol* signature = call.signature();
1989 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
1990 }
1991 #endif // !SHARK
1992 }
1993
1994
1995 oop nmethod::embeddedOop_at(u_char* p) {
1996 RelocIterator iter(this, p, p + 1);
1997 while (iter.next())
1998 if (iter.type() == relocInfo::oop_type) {
1999 return iter.oop_reloc()->oop_value();
2000 }
2001 return NULL;
2002 }
2003
2004
2005 inline bool includes(void* p, void* from, void* to) {
2006 return from <= p && p < to;
2007 }
2008
2009
2010 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2011 assert(count >= 2, "must be sentinel values, at least");
2012
2013 #ifdef ASSERT
2014 // must be sorted and unique; we do a binary search in find_pc_desc()
2015 int prev_offset = pcs[0].pc_offset();
2016 assert(prev_offset == PcDesc::lower_offset_limit,
2017 "must start with a sentinel");
2018 for (int i = 1; i < count; i++) {
2019 int this_offset = pcs[i].pc_offset();
2020 assert(this_offset > prev_offset, "offsets must be sorted");
2021 prev_offset = this_offset;
2022 }
2023 assert(prev_offset == PcDesc::upper_offset_limit,
2024 "must end with a sentinel");
2025 #endif //ASSERT
2026
2027 // Search for MethodHandle invokes and tag the nmethod.
2028 for (int i = 0; i < count; i++) {
2029 if (pcs[i].is_method_handle_invoke()) {
2030 set_has_method_handle_invokes(true);
2031 break;
2032 }
2033 }
2034 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2035
2036 int size = count * sizeof(PcDesc);
2037 assert(scopes_pcs_size() >= size, "oob");
2038 memcpy(scopes_pcs_begin(), pcs, size);
2039
2040 // Adjust the final sentinel downward.
2041 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2042 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2043 last_pc->set_pc_offset(content_size() + 1);
2044 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2045 // Fill any rounding gaps with copies of the last record.
2046 last_pc[1] = last_pc[0];
2047 }
2048 // The following assert could fail if sizeof(PcDesc) is not
2049 // an integral multiple of oopSize (the rounding term).
2050 // If it fails, change the logic to always allocate a multiple
2051 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2052 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2053 }
2054
2055 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2056 assert(scopes_data_size() >= size, "oob");
2057 memcpy(scopes_data_begin(), buffer, size);
2058 }
2059
2060
2061 #ifdef ASSERT
2062 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2063 PcDesc* lower = nm->scopes_pcs_begin();
2064 PcDesc* upper = nm->scopes_pcs_end();
2065 lower += 1; // exclude initial sentinel
2066 PcDesc* res = NULL;
2067 for (PcDesc* p = lower; p < upper; p++) {
2068 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2069 if (match_desc(p, pc_offset, approximate)) {
2070 if (res == NULL)
2071 res = p;
2072 else
2073 res = (PcDesc*) badAddress;
2074 }
2075 }
2076 return res;
2077 }
2078 #endif
2079
2080
2081 // Finds a PcDesc with real-pc equal to "pc"
2082 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2083 address base_address = code_begin();
2084 if ((pc < base_address) ||
2085 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2086 return NULL; // PC is wildly out of range
2087 }
2088 int pc_offset = (int) (pc - base_address);
2089
2090 // Check the PcDesc cache if it contains the desired PcDesc
2091 // (This as an almost 100% hit rate.)
2092 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2093 if (res != NULL) {
2094 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2095 return res;
2096 }
2097
2098 // Fallback algorithm: quasi-linear search for the PcDesc
2099 // Find the last pc_offset less than the given offset.
2100 // The successor must be the required match, if there is a match at all.
2101 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2102 PcDesc* lower = scopes_pcs_begin();
2103 PcDesc* upper = scopes_pcs_end();
2104 upper -= 1; // exclude final sentinel
2105 if (lower >= upper) return NULL; // native method; no PcDescs at all
2106
2107 #define assert_LU_OK \
2108 /* invariant on lower..upper during the following search: */ \
2109 assert(lower->pc_offset() < pc_offset, "sanity"); \
2110 assert(upper->pc_offset() >= pc_offset, "sanity")
2111 assert_LU_OK;
2112
2113 // Use the last successful return as a split point.
2114 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2115 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2116 if (mid->pc_offset() < pc_offset) {
2117 lower = mid;
2118 } else {
2119 upper = mid;
2120 }
2121
2122 // Take giant steps at first (4096, then 256, then 16, then 1)
2123 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2124 const int RADIX = (1 << LOG2_RADIX);
2125 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2126 while ((mid = lower + step) < upper) {
2127 assert_LU_OK;
2128 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2129 if (mid->pc_offset() < pc_offset) {
2130 lower = mid;
2131 } else {
2132 upper = mid;
2133 break;
2134 }
2135 }
2136 assert_LU_OK;
2137 }
2138
2139 // Sneak up on the value with a linear search of length ~16.
2140 while (true) {
2141 assert_LU_OK;
2142 mid = lower + 1;
2143 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2144 if (mid->pc_offset() < pc_offset) {
2145 lower = mid;
2146 } else {
2147 upper = mid;
2148 break;
2149 }
2150 }
2151 #undef assert_LU_OK
2152
2153 if (match_desc(upper, pc_offset, approximate)) {
2154 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2155 _pc_desc_cache.add_pc_desc(upper);
2156 return upper;
2157 } else {
2158 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2159 return NULL;
2160 }
2161 }
2162
2163
2164 void nmethod::check_all_dependencies(DepChange& changes) {
2165 // Checked dependencies are allocated into this ResourceMark
2166 ResourceMark rm;
2167
2168 // Turn off dependency tracing while actually testing dependencies.
2169 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
2170
2171 // 'dep_signature_buffers' caches already checked dependencies.
2172 DependencySignatureBuffer dep_signature_buffers;
2173
2174 // Iterate over live nmethods and check dependencies of all nmethods that are not
2175 // marked for deoptimization. A particular dependency is only checked once.
2176 for(nmethod* nm = CodeCache::alive_nmethod(CodeCache::first()); nm != NULL; nm = CodeCache::alive_nmethod(CodeCache::next(nm))) {
2177 if (!nm->is_marked_for_deoptimization()) {
2178 for (Dependencies::DepStream deps(nm); deps.next(); ) {
2179 // Construct abstraction of a dependency.
2180 const DependencySignature* current_sig = new DependencySignature(deps);
2181 // Determine if 'deps' is already checked. If it is not checked,
2182 // 'add_if_missing()' adds the dependency signature and returns
2183 // false.
2184 if (!dep_signature_buffers.add_if_missing(*current_sig)) {
2185 if (deps.check_dependency() != NULL) {
2186 // Dependency checking failed. Print out information about the failed
2187 // dependency and finally fail with an assert. We can fail here, since
2188 // dependency checking is never done in a product build.
2189 ResourceMark rm;
2190 changes.print();
2191 nm->print();
2192 nm->print_dependencies();
2193 assert(false, "Should have been marked for deoptimization");
2194 }
2195 }
2196 }
2197 }
2198 }
2199 }
2200
2201 bool nmethod::check_dependency_on(DepChange& changes) {
2202 // What has happened:
2203 // 1) a new class dependee has been added
2204 // 2) dependee and all its super classes have been marked
2205 bool found_check = false; // set true if we are upset
2206 for (Dependencies::DepStream deps(this); deps.next(); ) {
2207 // Evaluate only relevant dependencies.
2208 if (deps.spot_check_dependency_at(changes) != NULL) {
2209 found_check = true;
2210 NOT_DEBUG(break);
2211 }
2212 }
2213 return found_check;
2214 }
2215
2216 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2217 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2218 Array<Method*>* dependee_methods = dependee_ik->methods();
2219 for (Dependencies::DepStream deps(this); deps.next(); ) {
2220 if (deps.type() == Dependencies::evol_method) {
2221 Method* method = deps.method_argument(0);
2222 for (int j = 0; j < dependee_methods->length(); j++) {
2223 if (dependee_methods->at(j) == method) {
2224 // RC_TRACE macro has an embedded ResourceMark
2225 RC_TRACE(0x01000000,
2226 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2227 _method->method_holder()->external_name(),
2228 _method->name()->as_C_string(),
2229 _method->signature()->as_C_string(), compile_id(),
2230 method->method_holder()->external_name(),
2231 method->name()->as_C_string(),
2232 method->signature()->as_C_string()));
2233 if (TraceDependencies || LogCompilation)
2234 deps.log_dependency(dependee);
2235 return true;
2236 }
2237 }
2238 }
2239 }
2240 return false;
2241 }
2242
2243 // Called from mark_for_deoptimization, when dependee is invalidated.
2244 bool nmethod::is_dependent_on_method(Method* dependee) {
2245 for (Dependencies::DepStream deps(this); deps.next(); ) {
2246 if (deps.type() != Dependencies::evol_method)
2247 continue;
2248 Method* method = deps.method_argument(0);
2249 if (method == dependee) return true;
2250 }
2251 return false;
2252 }
2253
2254
2255 bool nmethod::is_patchable_at(address instr_addr) {
2256 assert(insts_contains(instr_addr), "wrong nmethod used");
2257 if (is_zombie()) {
2258 // a zombie may never be patched
2259 return false;
2260 }
2261 return true;
2262 }
2263
2264
2265 address nmethod::continuation_for_implicit_exception(address pc) {
2266 // Exception happened outside inline-cache check code => we are inside
2267 // an active nmethod => use cpc to determine a return address
2268 int exception_offset = pc - code_begin();
2269 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2270 #ifdef ASSERT
2271 if (cont_offset == 0) {
2272 Thread* thread = ThreadLocalStorage::get_thread_slow();
2273 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2274 HandleMark hm(thread);
2275 ResourceMark rm(thread);
2276 CodeBlob* cb = CodeCache::find_blob(pc);
2277 assert(cb != NULL && cb == this, "");
2278 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2279 print();
2280 method()->print_codes();
2281 print_code();
2282 print_pcs();
2283 }
2284 #endif
2285 if (cont_offset == 0) {
2286 // Let the normal error handling report the exception
2287 return NULL;
2288 }
2289 return code_begin() + cont_offset;
2290 }
2291
2292
2293
2294 void nmethod_init() {
2295 // make sure you didn't forget to adjust the filler fields
2296 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2297 }
2298
2299
2300 //-------------------------------------------------------------------------------------------
2301
2302
2303 // QQQ might we make this work from a frame??
2304 nmethodLocker::nmethodLocker(address pc) {
2305 CodeBlob* cb = CodeCache::find_blob(pc);
2306 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2307 _nm = (nmethod*)cb;
2308 lock_nmethod(_nm);
2309 }
2310
2311 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2312 // should pass zombie_ok == true.
2313 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2314 if (nm == NULL) return;
2315 Atomic::inc(&nm->_lock_count);
2316 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2317 }
2318
2319 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2320 if (nm == NULL) return;
2321 Atomic::dec(&nm->_lock_count);
2322 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2323 }
2324
2325
2326 // -----------------------------------------------------------------------------
2327 // nmethod::get_deopt_original_pc
2328 //
2329 // Return the original PC for the given PC if:
2330 // (a) the given PC belongs to a nmethod and
2331 // (b) it is a deopt PC
2332 address nmethod::get_deopt_original_pc(const frame* fr) {
2333 if (fr->cb() == NULL) return NULL;
2334
2335 nmethod* nm = fr->cb()->as_nmethod_or_null();
2336 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2337 return nm->get_original_pc(fr);
2338
2339 return NULL;
2340 }
2341
2342
2343 // -----------------------------------------------------------------------------
2344 // MethodHandle
2345
2346 bool nmethod::is_method_handle_return(address return_pc) {
2347 if (!has_method_handle_invokes()) return false;
2348 PcDesc* pd = pc_desc_at(return_pc);
2349 if (pd == NULL)
2350 return false;
2351 return pd->is_method_handle_invoke();
2352 }
2353
2354
2355 // -----------------------------------------------------------------------------
2356 // Verification
2357
2358 class VerifyOopsClosure: public OopClosure {
2359 nmethod* _nm;
2360 bool _ok;
2361 public:
2362 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2363 bool ok() { return _ok; }
2364 virtual void do_oop(oop* p) {
2365 if ((*p) == NULL || (*p)->is_oop()) return;
2366 if (_ok) {
2367 _nm->print_nmethod(true);
2368 _ok = false;
2369 }
2370 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2371 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2372 }
2373 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2374 };
2375
2376 void nmethod::verify() {
2377
2378 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2379 // seems odd.
2380
2381 if( is_zombie() || is_not_entrant() )
2382 return;
2383
2384 // Make sure all the entry points are correctly aligned for patching.
2385 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2386
2387 // assert(method()->is_oop(), "must be valid");
2388
2389 ResourceMark rm;
2390
2391 if (!CodeCache::contains(this)) {
2392 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2393 }
2394
2395 if(is_native_method() )
2396 return;
2397
2398 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2399 if (nm != this) {
2400 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2401 this));
2402 }
2403
2404 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2405 if (! p->verify(this)) {
2406 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2407 }
2408 }
2409
2410 VerifyOopsClosure voc(this);
2411 oops_do(&voc);
2412 assert(voc.ok(), "embedded oops must be OK");
2413 verify_scavenge_root_oops();
2414
2415 verify_scopes();
2416 }
2417
2418
2419 void nmethod::verify_interrupt_point(address call_site) {
2420 // Verify IC only when nmethod installation is finished.
2421 bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed
2422 || !this->is_in_use(); // nmethod is installed, but not in 'in_use' state
2423 if (is_installed) {
2424 Thread *cur = Thread::current();
2425 if (CompiledIC_lock->owner() == cur ||
2426 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2427 SafepointSynchronize::is_at_safepoint())) {
2428 CompiledIC_at(this, call_site);
2429 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2430 } else {
2431 MutexLocker ml_verify (CompiledIC_lock);
2432 CompiledIC_at(this, call_site);
2433 }
2434 }
2435
2436 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2437 assert(pd != NULL, "PcDesc must exist");
2438 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2439 pd->obj_decode_offset(), pd->should_reexecute(),
2440 pd->return_oop());
2441 !sd->is_top(); sd = sd->sender()) {
2442 sd->verify();
2443 }
2444 }
2445
2446 void nmethod::verify_scopes() {
2447 if( !method() ) return; // Runtime stubs have no scope
2448 if (method()->is_native()) return; // Ignore stub methods.
2449 // iterate through all interrupt point
2450 // and verify the debug information is valid.
2451 RelocIterator iter((nmethod*)this);
2452 while (iter.next()) {
2453 address stub = NULL;
2454 switch (iter.type()) {
2455 case relocInfo::virtual_call_type:
2456 verify_interrupt_point(iter.addr());
2457 break;
2458 case relocInfo::opt_virtual_call_type:
2459 stub = iter.opt_virtual_call_reloc()->static_stub();
2460 verify_interrupt_point(iter.addr());
2461 break;
2462 case relocInfo::static_call_type:
2463 stub = iter.static_call_reloc()->static_stub();
2464 //verify_interrupt_point(iter.addr());
2465 break;
2466 case relocInfo::runtime_call_type:
2467 address destination = iter.reloc()->value();
2468 // Right now there is no way to find out which entries support
2469 // an interrupt point. It would be nice if we had this
2470 // information in a table.
2471 break;
2472 }
2473 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2474 }
2475 }
2476
2477
2478 // -----------------------------------------------------------------------------
2479 // Non-product code
2480 #ifndef PRODUCT
2481
2482 class DebugScavengeRoot: public OopClosure {
2483 nmethod* _nm;
2484 bool _ok;
2485 public:
2486 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2487 bool ok() { return _ok; }
2488 virtual void do_oop(oop* p) {
2489 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2490 if (_ok) {
2491 _nm->print_nmethod(true);
2492 _ok = false;
2493 }
2494 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2495 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2496 (*p)->print();
2497 }
2498 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2499 };
2500
2501 void nmethod::verify_scavenge_root_oops() {
2502 if (!on_scavenge_root_list()) {
2503 // Actually look inside, to verify the claim that it's clean.
2504 DebugScavengeRoot debug_scavenge_root(this);
2505 oops_do(&debug_scavenge_root);
2506 if (!debug_scavenge_root.ok())
2507 fatal("found an unadvertised bad scavengable oop in the code cache");
2508 }
2509 assert(scavenge_root_not_marked(), "");
2510 }
2511
2512 #endif // PRODUCT
2513
2514 // Printing operations
2515
2516 void nmethod::print() const {
2517 ResourceMark rm;
2518 ttyLocker ttyl; // keep the following output all in one block
2519
2520 tty->print("Compiled method ");
2521
2522 if (is_compiled_by_c1()) {
2523 tty->print("(c1) ");
2524 } else if (is_compiled_by_c2()) {
2525 tty->print("(c2) ");
2526 } else if (is_compiled_by_shark()) {
2527 tty->print("(shark) ");
2528 } else {
2529 tty->print("(nm) ");
2530 }
2531
2532 print_on(tty, NULL);
2533
2534 if (WizardMode) {
2535 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2536 tty->print(" for method " INTPTR_FORMAT , (address)method());
2537 tty->print(" { ");
2538 if (is_in_use()) tty->print("in_use ");
2539 if (is_not_entrant()) tty->print("not_entrant ");
2540 if (is_zombie()) tty->print("zombie ");
2541 if (is_unloaded()) tty->print("unloaded ");
2542 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2543 tty->print_cr("}:");
2544 }
2545 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2546 (address)this,
2547 (address)this + size(),
2548 size());
2549 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2550 relocation_begin(),
2551 relocation_end(),
2552 relocation_size());
2553 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2554 consts_begin(),
2555 consts_end(),
2556 consts_size());
2557 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2558 insts_begin(),
2559 insts_end(),
2560 insts_size());
2561 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2562 stub_begin(),
2563 stub_end(),
2564 stub_size());
2565 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2566 oops_begin(),
2567 oops_end(),
2568 oops_size());
2569 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2570 metadata_begin(),
2571 metadata_end(),
2572 metadata_size());
2573 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2574 scopes_data_begin(),
2575 scopes_data_end(),
2576 scopes_data_size());
2577 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2578 scopes_pcs_begin(),
2579 scopes_pcs_end(),
2580 scopes_pcs_size());
2581 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2582 dependencies_begin(),
2583 dependencies_end(),
2584 dependencies_size());
2585 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2586 handler_table_begin(),
2587 handler_table_end(),
2588 handler_table_size());
2589 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2590 nul_chk_table_begin(),
2591 nul_chk_table_end(),
2592 nul_chk_table_size());
2593 }
2594
2595 void nmethod::print_code() {
2596 HandleMark hm;
2597 ResourceMark m;
2598 Disassembler::decode(this);
2599 }
2600
2601
2602 #ifndef PRODUCT
2603
2604 void nmethod::print_scopes() {
2605 // Find the first pc desc for all scopes in the code and print it.
2606 ResourceMark rm;
2607 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2608 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2609 continue;
2610
2611 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2612 sd->print_on(tty, p);
2613 }
2614 }
2615
2616 void nmethod::print_dependencies() {
2617 ResourceMark rm;
2618 ttyLocker ttyl; // keep the following output all in one block
2619 tty->print_cr("Dependencies:");
2620 for (Dependencies::DepStream deps(this); deps.next(); ) {
2621 deps.print_dependency();
2622 Klass* ctxk = deps.context_type();
2623 if (ctxk != NULL) {
2624 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2625 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2626 }
2627 }
2628 deps.log_dependency(); // put it into the xml log also
2629 }
2630 }
2631
2632
2633 void nmethod::print_relocations() {
2634 ResourceMark m; // in case methods get printed via the debugger
2635 tty->print_cr("relocations:");
2636 RelocIterator iter(this);
2637 iter.print();
2638 if (UseRelocIndex) {
2639 jint* index_end = (jint*)relocation_end() - 1;
2640 jint index_size = *index_end;
2641 jint* index_start = (jint*)( (address)index_end - index_size );
2642 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2643 if (index_size > 0) {
2644 jint* ip;
2645 for (ip = index_start; ip+2 <= index_end; ip += 2)
2646 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2647 ip[0],
2648 ip[1],
2649 header_end()+ip[0],
2650 relocation_begin()-1+ip[1]);
2651 for (; ip < index_end; ip++)
2652 tty->print_cr(" (%d ?)", ip[0]);
2653 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip);
2654 ip++;
2655 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2656 }
2657 }
2658 }
2659
2660
2661 void nmethod::print_pcs() {
2662 ResourceMark m; // in case methods get printed via debugger
2663 tty->print_cr("pc-bytecode offsets:");
2664 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2665 p->print(this);
2666 }
2667 }
2668
2669 #endif // PRODUCT
2670
2671 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2672 RelocIterator iter(this, begin, end);
2673 bool have_one = false;
2674 while (iter.next()) {
2675 have_one = true;
2676 switch (iter.type()) {
2677 case relocInfo::none: return "no_reloc";
2678 case relocInfo::oop_type: {
2679 stringStream st;
2680 oop_Relocation* r = iter.oop_reloc();
2681 oop obj = r->oop_value();
2682 st.print("oop(");
2683 if (obj == NULL) st.print("NULL");
2684 else obj->print_value_on(&st);
2685 st.print(")");
2686 return st.as_string();
2687 }
2688 case relocInfo::metadata_type: {
2689 stringStream st;
2690 metadata_Relocation* r = iter.metadata_reloc();
2691 Metadata* obj = r->metadata_value();
2692 st.print("metadata(");
2693 if (obj == NULL) st.print("NULL");
2694 else obj->print_value_on(&st);
2695 st.print(")");
2696 return st.as_string();
2697 }
2698 case relocInfo::virtual_call_type: return "virtual_call";
2699 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2700 case relocInfo::static_call_type: return "static_call";
2701 case relocInfo::static_stub_type: return "static_stub";
2702 case relocInfo::runtime_call_type: return "runtime_call";
2703 case relocInfo::external_word_type: return "external_word";
2704 case relocInfo::internal_word_type: return "internal_word";
2705 case relocInfo::section_word_type: return "section_word";
2706 case relocInfo::poll_type: return "poll";
2707 case relocInfo::poll_return_type: return "poll_return";
2708 case relocInfo::type_mask: return "type_bit_mask";
2709 }
2710 }
2711 return have_one ? "other" : NULL;
2712 }
2713
2714 // Return a the last scope in (begin..end]
2715 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2716 PcDesc* p = pc_desc_near(begin+1);
2717 if (p != NULL && p->real_pc(this) <= end) {
2718 return new ScopeDesc(this, p->scope_decode_offset(),
2719 p->obj_decode_offset(), p->should_reexecute(),
2720 p->return_oop());
2721 }
2722 return NULL;
2723 }
2724
2725 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2726 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2727 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2728 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2729 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2730 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2731
2732 if (has_method_handle_invokes())
2733 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
2734
2735 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
2736
2737 if (block_begin == entry_point()) {
2738 methodHandle m = method();
2739 if (m.not_null()) {
2740 stream->print(" # ");
2741 m->print_value_on(stream);
2742 stream->cr();
2743 }
2744 if (m.not_null() && !is_osr_method()) {
2745 ResourceMark rm;
2746 int sizeargs = m->size_of_parameters();
2747 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2748 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2749 {
2750 int sig_index = 0;
2751 if (!m->is_static())
2752 sig_bt[sig_index++] = T_OBJECT; // 'this'
2753 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2754 BasicType t = ss.type();
2755 sig_bt[sig_index++] = t;
2756 if (type2size[t] == 2) {
2757 sig_bt[sig_index++] = T_VOID;
2758 } else {
2759 assert(type2size[t] == 1, "size is 1 or 2");
2760 }
2761 }
2762 assert(sig_index == sizeargs, "");
2763 }
2764 const char* spname = "sp"; // make arch-specific?
2765 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2766 int stack_slot_offset = this->frame_size() * wordSize;
2767 int tab1 = 14, tab2 = 24;
2768 int sig_index = 0;
2769 int arg_index = (m->is_static() ? 0 : -1);
2770 bool did_old_sp = false;
2771 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2772 bool at_this = (arg_index == -1);
2773 bool at_old_sp = false;
2774 BasicType t = (at_this ? T_OBJECT : ss.type());
2775 assert(t == sig_bt[sig_index], "sigs in sync");
2776 if (at_this)
2777 stream->print(" # this: ");
2778 else
2779 stream->print(" # parm%d: ", arg_index);
2780 stream->move_to(tab1);
2781 VMReg fst = regs[sig_index].first();
2782 VMReg snd = regs[sig_index].second();
2783 if (fst->is_reg()) {
2784 stream->print("%s", fst->name());
2785 if (snd->is_valid()) {
2786 stream->print(":%s", snd->name());
2787 }
2788 } else if (fst->is_stack()) {
2789 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2790 if (offset == stack_slot_offset) at_old_sp = true;
2791 stream->print("[%s+0x%x]", spname, offset);
2792 } else {
2793 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2794 }
2795 stream->print(" ");
2796 stream->move_to(tab2);
2797 stream->print("= ");
2798 if (at_this) {
2799 m->method_holder()->print_value_on(stream);
2800 } else {
2801 bool did_name = false;
2802 if (!at_this && ss.is_object()) {
2803 Symbol* name = ss.as_symbol_or_null();
2804 if (name != NULL) {
2805 name->print_value_on(stream);
2806 did_name = true;
2807 }
2808 }
2809 if (!did_name)
2810 stream->print("%s", type2name(t));
2811 }
2812 if (at_old_sp) {
2813 stream->print(" (%s of caller)", spname);
2814 did_old_sp = true;
2815 }
2816 stream->cr();
2817 sig_index += type2size[t];
2818 arg_index += 1;
2819 if (!at_this) ss.next();
2820 }
2821 if (!did_old_sp) {
2822 stream->print(" # ");
2823 stream->move_to(tab1);
2824 stream->print("[%s+0x%x]", spname, stack_slot_offset);
2825 stream->print(" (%s of caller)", spname);
2826 stream->cr();
2827 }
2828 }
2829 }
2830 }
2831
2832 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2833 // First, find an oopmap in (begin, end].
2834 // We use the odd half-closed interval so that oop maps and scope descs
2835 // which are tied to the byte after a call are printed with the call itself.
2836 address base = code_begin();
2837 OopMapSet* oms = oop_maps();
2838 if (oms != NULL) {
2839 for (int i = 0, imax = oms->size(); i < imax; i++) {
2840 OopMap* om = oms->at(i);
2841 address pc = base + om->offset();
2842 if (pc > begin) {
2843 if (pc <= end) {
2844 st->move_to(column);
2845 st->print("; ");
2846 om->print_on(st);
2847 }
2848 break;
2849 }
2850 }
2851 }
2852
2853 // Print any debug info present at this pc.
2854 ScopeDesc* sd = scope_desc_in(begin, end);
2855 if (sd != NULL) {
2856 st->move_to(column);
2857 if (sd->bci() == SynchronizationEntryBCI) {
2858 st->print(";*synchronization entry");
2859 } else {
2860 if (sd->method() == NULL) {
2861 st->print("method is NULL");
2862 } else if (sd->method()->is_native()) {
2863 st->print("method is native");
2864 } else {
2865 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2866 st->print(";*%s", Bytecodes::name(bc));
2867 switch (bc) {
2868 case Bytecodes::_invokevirtual:
2869 case Bytecodes::_invokespecial:
2870 case Bytecodes::_invokestatic:
2871 case Bytecodes::_invokeinterface:
2872 {
2873 Bytecode_invoke invoke(sd->method(), sd->bci());
2874 st->print(" ");
2875 if (invoke.name() != NULL)
2876 invoke.name()->print_symbol_on(st);
2877 else
2878 st->print("<UNKNOWN>");
2879 break;
2880 }
2881 case Bytecodes::_getfield:
2882 case Bytecodes::_putfield:
2883 case Bytecodes::_getstatic:
2884 case Bytecodes::_putstatic:
2885 {
2886 Bytecode_field field(sd->method(), sd->bci());
2887 st->print(" ");
2888 if (field.name() != NULL)
2889 field.name()->print_symbol_on(st);
2890 else
2891 st->print("<UNKNOWN>");
2892 }
2893 }
2894 }
2895 }
2896
2897 // Print all scopes
2898 for (;sd != NULL; sd = sd->sender()) {
2899 st->move_to(column);
2900 st->print("; -");
2901 if (sd->method() == NULL) {
2902 st->print("method is NULL");
2903 } else {
2904 sd->method()->print_short_name(st);
2905 }
2906 int lineno = sd->method()->line_number_from_bci(sd->bci());
2907 if (lineno != -1) {
2908 st->print("@%d (line %d)", sd->bci(), lineno);
2909 } else {
2910 st->print("@%d", sd->bci());
2911 }
2912 st->cr();
2913 }
2914 }
2915
2916 // Print relocation information
2917 const char* str = reloc_string_for(begin, end);
2918 if (str != NULL) {
2919 if (sd != NULL) st->cr();
2920 st->move_to(column);
2921 st->print("; {%s}", str);
2922 }
2923 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2924 if (cont_offset != 0) {
2925 st->move_to(column);
2926 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
2927 }
2928
2929 }
2930
2931 #ifndef PRODUCT
2932
2933 void nmethod::print_value_on(outputStream* st) const {
2934 st->print("nmethod");
2935 print_on(st, NULL);
2936 }
2937
2938 void nmethod::print_calls(outputStream* st) {
2939 RelocIterator iter(this);
2940 while (iter.next()) {
2941 switch (iter.type()) {
2942 case relocInfo::virtual_call_type:
2943 case relocInfo::opt_virtual_call_type: {
2944 VerifyMutexLocker mc(CompiledIC_lock);
2945 CompiledIC_at(iter.reloc())->print();
2946 break;
2947 }
2948 case relocInfo::static_call_type:
2949 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2950 compiledStaticCall_at(iter.reloc())->print();
2951 break;
2952 }
2953 }
2954 }
2955
2956 void nmethod::print_handler_table() {
2957 ExceptionHandlerTable(this).print();
2958 }
2959
2960 void nmethod::print_nul_chk_table() {
2961 ImplicitExceptionTable(this).print(code_begin());
2962 }
2963
2964 void nmethod::print_statistics() {
2965 ttyLocker ttyl;
2966 if (xtty != NULL) xtty->head("statistics type='nmethod'");
2967 nmethod_stats.print_native_nmethod_stats();
2968 nmethod_stats.print_nmethod_stats();
2969 DebugInformationRecorder::print_statistics();
2970 nmethod_stats.print_pc_stats();
2971 Dependencies::print_statistics();
2972 if (xtty != NULL) xtty->tail("statistics");
2973 }
2974
2975 #endif // PRODUCT