1 /*
2 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "code/codeCache.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/dependencies.hpp"
29 #include "code/nmethod.hpp"
30 #include "code/scopeDesc.hpp"
31 #include "compiler/abstractCompiler.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/compileLog.hpp"
34 #include "compiler/compilerOracle.hpp"
35 #include "compiler/disassembler.hpp"
36 #include "interpreter/bytecode.hpp"
37 #include "oops/methodData.hpp"
38 #include "prims/jvmtiRedefineClassesTrace.hpp"
39 #include "prims/jvmtiImpl.hpp"
40 #include "runtime/sharedRuntime.hpp"
41 #include "runtime/sweeper.hpp"
42 #include "utilities/dtrace.hpp"
43 #include "utilities/events.hpp"
44 #include "utilities/xmlstream.hpp"
45 #ifdef SHARK
46 #include "shark/sharkCompiler.hpp"
47 #endif
48
49 #ifdef DTRACE_ENABLED
50
51 // Only bother with this argument setup if dtrace is available
52
53 #ifndef USDT2
54 HS_DTRACE_PROBE_DECL8(hotspot, compiled__method__load,
55 const char*, int, const char*, int, const char*, int, void*, size_t);
56
57 HS_DTRACE_PROBE_DECL6(hotspot, compiled__method__unload,
58 char*, int, char*, int, char*, int);
59
60 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
61 { \
62 Method* m = (method); \
63 if (m != NULL) { \
64 Symbol* klass_name = m->klass_name(); \
65 Symbol* name = m->name(); \
66 Symbol* signature = m->signature(); \
67 HS_DTRACE_PROBE6(hotspot, compiled__method__unload, \
68 klass_name->bytes(), klass_name->utf8_length(), \
69 name->bytes(), name->utf8_length(), \
70 signature->bytes(), signature->utf8_length()); \
71 } \
72 }
73 #else /* USDT2 */
74 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
75 { \
76 Method* m = (method); \
77 if (m != NULL) { \
78 Symbol* klass_name = m->klass_name(); \
79 Symbol* name = m->name(); \
80 Symbol* signature = m->signature(); \
81 HOTSPOT_COMPILED_METHOD_UNLOAD( \
82 (char *) klass_name->bytes(), klass_name->utf8_length(), \
83 (char *) name->bytes(), name->utf8_length(), \
84 (char *) signature->bytes(), signature->utf8_length()); \
85 } \
86 }
87 #endif /* USDT2 */
88
89 #else // ndef DTRACE_ENABLED
90
91 #define DTRACE_METHOD_UNLOAD_PROBE(method)
92
93 #endif
94
95 bool nmethod::is_compiled_by_c1() const {
96 if (compiler() == NULL || method() == NULL) return false; // can happen during debug printing
97 if (is_native_method()) return false;
98 return compiler()->is_c1();
99 }
100 bool nmethod::is_compiled_by_c2() const {
101 if (compiler() == NULL || method() == NULL) return false; // can happen during debug printing
102 if (is_native_method()) return false;
103 return compiler()->is_c2();
104 }
105 bool nmethod::is_compiled_by_shark() const {
106 if (is_native_method()) return false;
107 assert(compiler() != NULL, "must be");
108 return compiler()->is_shark();
109 }
110
111
112
113 //---------------------------------------------------------------------------------
114 // NMethod statistics
115 // They are printed under various flags, including:
116 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
117 // (In the latter two cases, they like other stats are printed to the log only.)
118
119 #ifndef PRODUCT
120 // These variables are put into one block to reduce relocations
121 // and make it simpler to print from the debugger.
122 static
123 struct nmethod_stats_struct {
124 int nmethod_count;
125 int total_size;
126 int relocation_size;
127 int consts_size;
128 int insts_size;
129 int stub_size;
130 int scopes_data_size;
131 int scopes_pcs_size;
132 int dependencies_size;
133 int handler_table_size;
134 int nul_chk_table_size;
135 int oops_size;
136
137 void note_nmethod(nmethod* nm) {
138 nmethod_count += 1;
139 total_size += nm->size();
140 relocation_size += nm->relocation_size();
141 consts_size += nm->consts_size();
142 insts_size += nm->insts_size();
143 stub_size += nm->stub_size();
144 oops_size += nm->oops_size();
145 scopes_data_size += nm->scopes_data_size();
146 scopes_pcs_size += nm->scopes_pcs_size();
147 dependencies_size += nm->dependencies_size();
148 handler_table_size += nm->handler_table_size();
149 nul_chk_table_size += nm->nul_chk_table_size();
150 }
151 void print_nmethod_stats() {
152 if (nmethod_count == 0) return;
153 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
154 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
155 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
156 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
157 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size);
158 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
159 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
160 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
161 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
162 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
163 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
164 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
165 }
166
167 int native_nmethod_count;
168 int native_total_size;
169 int native_relocation_size;
170 int native_insts_size;
171 int native_oops_size;
172 void note_native_nmethod(nmethod* nm) {
173 native_nmethod_count += 1;
174 native_total_size += nm->size();
175 native_relocation_size += nm->relocation_size();
176 native_insts_size += nm->insts_size();
177 native_oops_size += nm->oops_size();
178 }
179 void print_native_nmethod_stats() {
180 if (native_nmethod_count == 0) return;
181 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
182 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
183 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
184 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size);
185 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
186 }
187
188 int pc_desc_resets; // number of resets (= number of caches)
189 int pc_desc_queries; // queries to nmethod::find_pc_desc
190 int pc_desc_approx; // number of those which have approximate true
191 int pc_desc_repeats; // number of _pc_descs[0] hits
192 int pc_desc_hits; // number of LRU cache hits
193 int pc_desc_tests; // total number of PcDesc examinations
194 int pc_desc_searches; // total number of quasi-binary search steps
195 int pc_desc_adds; // number of LUR cache insertions
196
197 void print_pc_stats() {
198 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
199 pc_desc_queries,
200 (double)(pc_desc_tests + pc_desc_searches)
201 / pc_desc_queries);
202 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
203 pc_desc_resets,
204 pc_desc_queries, pc_desc_approx,
205 pc_desc_repeats, pc_desc_hits,
206 pc_desc_tests, pc_desc_searches, pc_desc_adds);
207 }
208 } nmethod_stats;
209 #endif //PRODUCT
210
211
212 //---------------------------------------------------------------------------------
213
214
215 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
216 assert(pc != NULL, "Must be non null");
217 assert(exception.not_null(), "Must be non null");
218 assert(handler != NULL, "Must be non null");
219
220 _count = 0;
221 _exception_type = exception->klass();
222 _next = NULL;
223
224 add_address_and_handler(pc,handler);
225 }
226
227
228 address ExceptionCache::match(Handle exception, address pc) {
229 assert(pc != NULL,"Must be non null");
230 assert(exception.not_null(),"Must be non null");
231 if (exception->klass() == exception_type()) {
232 return (test_address(pc));
233 }
234
235 return NULL;
236 }
237
238
239 bool ExceptionCache::match_exception_with_space(Handle exception) {
240 assert(exception.not_null(),"Must be non null");
241 if (exception->klass() == exception_type() && count() < cache_size) {
242 return true;
243 }
244 return false;
245 }
246
247
248 address ExceptionCache::test_address(address addr) {
249 for (int i=0; i<count(); i++) {
250 if (pc_at(i) == addr) {
251 return handler_at(i);
252 }
253 }
254 return NULL;
255 }
256
257
258 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
259 if (test_address(addr) == handler) return true;
260 if (count() < cache_size) {
261 set_pc_at(count(),addr);
262 set_handler_at(count(), handler);
263 increment_count();
264 return true;
265 }
266 return false;
267 }
268
269
270 // private method for handling exception cache
271 // These methods are private, and used to manipulate the exception cache
272 // directly.
273 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
274 ExceptionCache* ec = exception_cache();
275 while (ec != NULL) {
276 if (ec->match_exception_with_space(exception)) {
277 return ec;
278 }
279 ec = ec->next();
280 }
281 return NULL;
282 }
283
284
285 //-----------------------------------------------------------------------------
286
287
288 // Helper used by both find_pc_desc methods.
289 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
290 NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
291 if (!approximate)
292 return pc->pc_offset() == pc_offset;
293 else
294 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
295 }
296
297 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
298 if (initial_pc_desc == NULL) {
299 _pc_descs[0] = NULL; // native method; no PcDescs at all
300 return;
301 }
302 NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
303 // reset the cache by filling it with benign (non-null) values
304 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
305 for (int i = 0; i < cache_size; i++)
306 _pc_descs[i] = initial_pc_desc;
307 }
308
309 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
310 NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
311 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
312
313 // Note: one might think that caching the most recently
314 // read value separately would be a win, but one would be
315 // wrong. When many threads are updating it, the cache
316 // line it's in would bounce between caches, negating
317 // any benefit.
318
319 // In order to prevent race conditions do not load cache elements
320 // repeatedly, but use a local copy:
321 PcDesc* res;
322
323 // Step one: Check the most recently added value.
324 res = _pc_descs[0];
325 if (res == NULL) return NULL; // native method; no PcDescs at all
326 if (match_desc(res, pc_offset, approximate)) {
327 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
328 return res;
329 }
330
331 // Step two: Check the rest of the LRU cache.
332 for (int i = 1; i < cache_size; ++i) {
333 res = _pc_descs[i];
334 if (res->pc_offset() < 0) break; // optimization: skip empty cache
335 if (match_desc(res, pc_offset, approximate)) {
336 NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
337 return res;
338 }
339 }
340
341 // Report failure.
342 return NULL;
343 }
344
345 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
346 NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
347 // Update the LRU cache by shifting pc_desc forward.
348 for (int i = 0; i < cache_size; i++) {
349 PcDesc* next = _pc_descs[i];
350 _pc_descs[i] = pc_desc;
351 pc_desc = next;
352 }
353 }
354
355 // adjust pcs_size so that it is a multiple of both oopSize and
356 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
357 // of oopSize, then 2*sizeof(PcDesc) is)
358 static int adjust_pcs_size(int pcs_size) {
359 int nsize = round_to(pcs_size, oopSize);
360 if ((nsize % sizeof(PcDesc)) != 0) {
361 nsize = pcs_size + sizeof(PcDesc);
362 }
363 assert((nsize % oopSize) == 0, "correct alignment");
364 return nsize;
365 }
366
367 //-----------------------------------------------------------------------------
368
369
370 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
371 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
372 assert(new_entry != NULL,"Must be non null");
373 assert(new_entry->next() == NULL, "Must be null");
374
375 if (exception_cache() != NULL) {
376 new_entry->set_next(exception_cache());
377 }
378 set_exception_cache(new_entry);
379 }
380
381 void nmethod::remove_from_exception_cache(ExceptionCache* ec) {
382 ExceptionCache* prev = NULL;
383 ExceptionCache* curr = exception_cache();
384 assert(curr != NULL, "nothing to remove");
385 // find the previous and next entry of ec
386 while (curr != ec) {
387 prev = curr;
388 curr = curr->next();
389 assert(curr != NULL, "ExceptionCache not found");
390 }
391 // now: curr == ec
392 ExceptionCache* next = curr->next();
393 if (prev == NULL) {
394 set_exception_cache(next);
395 } else {
396 prev->set_next(next);
397 }
398 delete curr;
399 }
400
401
402 // public method for accessing the exception cache
403 // These are the public access methods.
404 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
405 // We never grab a lock to read the exception cache, so we may
406 // have false negatives. This is okay, as it can only happen during
407 // the first few exception lookups for a given nmethod.
408 ExceptionCache* ec = exception_cache();
409 while (ec != NULL) {
410 address ret_val;
411 if ((ret_val = ec->match(exception,pc)) != NULL) {
412 return ret_val;
413 }
414 ec = ec->next();
415 }
416 return NULL;
417 }
418
419
420 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
421 // There are potential race conditions during exception cache updates, so we
422 // must own the ExceptionCache_lock before doing ANY modifications. Because
423 // we don't lock during reads, it is possible to have several threads attempt
424 // to update the cache with the same data. We need to check for already inserted
425 // copies of the current data before adding it.
426
427 MutexLocker ml(ExceptionCache_lock);
428 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
429
430 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
431 target_entry = new ExceptionCache(exception,pc,handler);
432 add_exception_cache_entry(target_entry);
433 }
434 }
435
436
437 //-------------end of code for ExceptionCache--------------
438
439
440 int nmethod::total_size() const {
441 return
442 consts_size() +
443 insts_size() +
444 stub_size() +
445 scopes_data_size() +
446 scopes_pcs_size() +
447 handler_table_size() +
448 nul_chk_table_size();
449 }
450
451 const char* nmethod::compile_kind() const {
452 if (is_osr_method()) return "osr";
453 if (method() != NULL && is_native_method()) return "c2n";
454 return NULL;
455 }
456
457 // Fill in default values for various flag fields
458 void nmethod::init_defaults() {
459 _state = alive;
460 _marked_for_reclamation = 0;
461 _has_flushed_dependencies = 0;
462 _speculatively_disconnected = 0;
463 _has_unsafe_access = 0;
464 _has_method_handle_invokes = 0;
465 _lazy_critical_native = 0;
466 _has_wide_vectors = 0;
467 _marked_for_deoptimization = 0;
468 _lock_count = 0;
469 _stack_traversal_mark = 0;
470 _unload_reported = false; // jvmti state
471
472 #ifdef ASSERT
473 _oops_are_stale = false;
474 #endif
475
476 _oops_do_mark_link = NULL;
477 _jmethod_id = NULL;
478 _osr_link = NULL;
479 _scavenge_root_link = NULL;
480 _scavenge_root_state = 0;
481 _saved_nmethod_link = NULL;
482 _compiler = NULL;
483
484 #ifdef HAVE_DTRACE_H
485 _trap_offset = 0;
486 #endif // def HAVE_DTRACE_H
487 }
488
489
490 nmethod* nmethod::new_native_nmethod(methodHandle method,
491 int compile_id,
492 CodeBuffer *code_buffer,
493 int vep_offset,
494 int frame_complete,
495 int frame_size,
496 ByteSize basic_lock_owner_sp_offset,
497 ByteSize basic_lock_sp_offset,
498 OopMapSet* oop_maps) {
499 code_buffer->finalize_oop_references(method);
500 // create nmethod
501 nmethod* nm = NULL;
502 {
503 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
504 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
505 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)
509 nmethod(method(), native_nmethod_size, compile_id, &offsets,
510 code_buffer, frame_size,
511 basic_lock_owner_sp_offset, basic_lock_sp_offset,
512 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 // verify nmethod
518 debug_only(if (nm) nm->verify();) // might block
519
520 if (nm != NULL) {
521 nm->log_new_nmethod();
522 }
523
524 return nm;
525 }
526
527 #ifdef HAVE_DTRACE_H
528 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
529 CodeBuffer *code_buffer,
530 int vep_offset,
531 int trap_offset,
532 int frame_complete,
533 int frame_size) {
534 code_buffer->finalize_oop_references(method);
535 // create nmethod
536 nmethod* nm = NULL;
537 {
538 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
539 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
540 CodeOffsets offsets;
541 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
542 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
543 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
544
545 nm = new (nmethod_size) nmethod(method(), nmethod_size, &offsets, code_buffer, frame_size);
546
547 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
548 if (PrintAssembly && nm != NULL)
549 Disassembler::decode(nm);
550 }
551 // verify nmethod
552 debug_only(if (nm) nm->verify();) // might block
553
554 if (nm != NULL) {
555 nm->log_new_nmethod();
556 }
557
558 return nm;
559 }
560
561 #endif // def HAVE_DTRACE_H
562
563 nmethod* nmethod::new_nmethod(methodHandle method,
564 int compile_id,
565 int entry_bci,
566 CodeOffsets* offsets,
567 int orig_pc_offset,
568 DebugInformationRecorder* debug_info,
569 Dependencies* dependencies,
570 CodeBuffer* code_buffer, int frame_size,
571 OopMapSet* oop_maps,
572 ExceptionHandlerTable* handler_table,
573 ImplicitExceptionTable* nul_chk_table,
574 AbstractCompiler* compiler,
575 int comp_level
576 )
577 {
578 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
579 code_buffer->finalize_oop_references(method);
580 // create nmethod
581 nmethod* nm = NULL;
582 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
583 int nmethod_size =
584 allocation_size(code_buffer, sizeof(nmethod))
585 + adjust_pcs_size(debug_info->pcs_size())
586 + round_to(dependencies->size_in_bytes() , oopSize)
587 + round_to(handler_table->size_in_bytes(), oopSize)
588 + round_to(nul_chk_table->size_in_bytes(), oopSize)
589 + round_to(debug_info->data_size() , oopSize);
590 nm = new (nmethod_size)
591 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
592 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
593 oop_maps,
594 handler_table,
595 nul_chk_table,
596 compiler,
597 comp_level);
598 if (nm != NULL) {
599 // To make dependency checking during class loading fast, record
600 // the nmethod dependencies in the classes it is dependent on.
601 // This allows the dependency checking code to simply walk the
602 // class hierarchy above the loaded class, checking only nmethods
603 // which are dependent on those classes. The slow way is to
604 // check every nmethod for dependencies which makes it linear in
605 // the number of methods compiled. For applications with a lot
606 // classes the slow way is too slow.
607 for (Dependencies::DepStream deps(nm); deps.next(); ) {
608 Klass* klass = deps.context_type();
609 if (klass == NULL) continue; // ignore things like evol_method
610
611 // record this nmethod as dependent on this klass
612 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
613 }
614 }
615 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
616 if (PrintAssembly && nm != NULL)
617 Disassembler::decode(nm);
618 }
619
620 // verify nmethod
621 debug_only(if (nm) nm->verify();) // might block
622
623 if (nm != NULL) {
624 nm->log_new_nmethod();
625 }
626
627 // done
628 return nm;
629 }
630
631
632 // For native wrappers
633 nmethod::nmethod(
634 Method* method,
635 int nmethod_size,
636 int compile_id,
637 CodeOffsets* offsets,
638 CodeBuffer* code_buffer,
639 int frame_size,
640 ByteSize basic_lock_owner_sp_offset,
641 ByteSize basic_lock_sp_offset,
642 OopMapSet* oop_maps )
643 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
644 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
645 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
646 _native_basic_lock_sp_offset(basic_lock_sp_offset)
647 {
648 {
649 debug_only(No_Safepoint_Verifier nsv;)
650 assert_locked_or_safepoint(CodeCache_lock);
651
652 init_defaults();
653 _method = method;
654 _entry_bci = InvocationEntryBci;
655 // We have no exception handler or deopt handler make the
656 // values something that will never match a pc like the nmethod vtable entry
657 _exception_offset = 0;
658 _deoptimize_offset = 0;
659 _deoptimize_mh_offset = 0;
660 _orig_pc_offset = 0;
661
662 _consts_offset = data_offset();
663 _stub_offset = data_offset();
664 _oops_offset = data_offset();
665 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
666 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
667 _scopes_pcs_offset = _scopes_data_offset;
668 _dependencies_offset = _scopes_pcs_offset;
669 _handler_table_offset = _dependencies_offset;
670 _nul_chk_table_offset = _handler_table_offset;
671 _nmethod_end_offset = _nul_chk_table_offset;
672 _compile_id = compile_id;
673 _comp_level = CompLevel_none;
674 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
675 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
676 _osr_entry_point = NULL;
677 _exception_cache = NULL;
678 _pc_desc_cache.reset_to(NULL);
679
680 code_buffer->copy_values_to(this);
681 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
682 CodeCache::add_scavenge_root_nmethod(this);
683 }
684 debug_only(verify_scavenge_root_oops());
685 CodeCache::commit(this);
686 }
687
688 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
689 ttyLocker ttyl; // keep the following output all in one block
690 // This output goes directly to the tty, not the compiler log.
691 // To enable tools to match it up with the compilation activity,
692 // be sure to tag this tty output with the compile ID.
693 if (xtty != NULL) {
694 xtty->begin_head("print_native_nmethod");
695 xtty->method(_method);
696 xtty->stamp();
697 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
698 }
699 // print the header part first
700 print();
701 // then print the requested information
702 if (PrintNativeNMethods) {
703 print_code();
704 if (oop_maps != NULL) {
705 oop_maps->print();
706 }
707 }
708 if (PrintRelocations) {
709 print_relocations();
710 }
711 if (xtty != NULL) {
712 xtty->tail("print_native_nmethod");
713 }
714 }
715 }
716
717 // For dtrace wrappers
718 #ifdef HAVE_DTRACE_H
719 nmethod::nmethod(
720 Method* method,
721 int nmethod_size,
722 CodeOffsets* offsets,
723 CodeBuffer* code_buffer,
724 int frame_size)
725 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
726 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
727 _native_receiver_sp_offset(in_ByteSize(-1)),
728 _native_basic_lock_sp_offset(in_ByteSize(-1))
729 {
730 {
731 debug_only(No_Safepoint_Verifier nsv;)
732 assert_locked_or_safepoint(CodeCache_lock);
733
734 init_defaults();
735 _method = method;
736 _entry_bci = InvocationEntryBci;
737 // We have no exception handler or deopt handler make the
738 // values something that will never match a pc like the nmethod vtable entry
739 _exception_offset = 0;
740 _deoptimize_offset = 0;
741 _deoptimize_mh_offset = 0;
742 _unwind_handler_offset = -1;
743 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
744 _orig_pc_offset = 0;
745 _consts_offset = data_offset();
746 _stub_offset = data_offset();
747 _oops_offset = data_offset();
748 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
749 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
750 _scopes_pcs_offset = _scopes_data_offset;
751 _dependencies_offset = _scopes_pcs_offset;
752 _handler_table_offset = _dependencies_offset;
753 _nul_chk_table_offset = _handler_table_offset;
754 _nmethod_end_offset = _nul_chk_table_offset;
755 _compile_id = 0; // default
756 _comp_level = CompLevel_none;
757 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
758 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
759 _osr_entry_point = NULL;
760 _exception_cache = NULL;
761 _pc_desc_cache.reset_to(NULL);
762
763 code_buffer->copy_values_to(this);
764 debug_only(verify_scavenge_root_oops());
765 CodeCache::commit(this);
766 }
767
768 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
769 ttyLocker ttyl; // keep the following output all in one block
770 // This output goes directly to the tty, not the compiler log.
771 // To enable tools to match it up with the compilation activity,
772 // be sure to tag this tty output with the compile ID.
773 if (xtty != NULL) {
774 xtty->begin_head("print_dtrace_nmethod");
775 xtty->method(_method);
776 xtty->stamp();
777 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
778 }
779 // print the header part first
780 print();
781 // then print the requested information
782 if (PrintNMethods) {
783 print_code();
784 }
785 if (PrintRelocations) {
786 print_relocations();
787 }
788 if (xtty != NULL) {
789 xtty->tail("print_dtrace_nmethod");
790 }
791 }
792 }
793 #endif // def HAVE_DTRACE_H
794
795 void* nmethod::operator new(size_t size, int nmethod_size) {
796 // Always leave some room in the CodeCache for I2C/C2I adapters
797 if (CodeCache::largest_free_block() < CodeCacheMinimumFreeSpace) return NULL;
798 return CodeCache::allocate(nmethod_size);
799 }
800
801
802 nmethod::nmethod(
803 Method* method,
804 int nmethod_size,
805 int compile_id,
806 int entry_bci,
807 CodeOffsets* offsets,
808 int orig_pc_offset,
809 DebugInformationRecorder* debug_info,
810 Dependencies* dependencies,
811 CodeBuffer *code_buffer,
812 int frame_size,
813 OopMapSet* oop_maps,
814 ExceptionHandlerTable* handler_table,
815 ImplicitExceptionTable* nul_chk_table,
816 AbstractCompiler* compiler,
817 int comp_level
818 )
819 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
820 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
821 _native_receiver_sp_offset(in_ByteSize(-1)),
822 _native_basic_lock_sp_offset(in_ByteSize(-1))
823 {
824 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
825 {
826 debug_only(No_Safepoint_Verifier nsv;)
827 assert_locked_or_safepoint(CodeCache_lock);
828
829 init_defaults();
830 _method = method;
831 _entry_bci = entry_bci;
832 _compile_id = compile_id;
833 _comp_level = comp_level;
834 _compiler = compiler;
835 _orig_pc_offset = orig_pc_offset;
836
837 // Section offsets
838 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
839 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
840
841 // Exception handler and deopt handler are in the stub section
842 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
843 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
844 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
845 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
846 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
847 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
848 } else {
849 _deoptimize_mh_offset = -1;
850 }
851 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
852 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
853 } else {
854 _unwind_handler_offset = -1;
855 }
856
857 _oops_offset = data_offset();
858 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
859 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
860
861 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
862 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
863 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
864 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
865 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
866
867 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
868 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
869 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
870 _exception_cache = NULL;
871 _pc_desc_cache.reset_to(scopes_pcs_begin());
872
873 // Copy contents of ScopeDescRecorder to nmethod
874 code_buffer->copy_values_to(this);
875 debug_info->copy_to(this);
876 dependencies->copy_to(this);
877 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
878 CodeCache::add_scavenge_root_nmethod(this);
879 }
880 debug_only(verify_scavenge_root_oops());
881
882 CodeCache::commit(this);
883
884 // Copy contents of ExceptionHandlerTable to nmethod
885 handler_table->copy_to(this);
886 nul_chk_table->copy_to(this);
887
888 // we use the information of entry points to find out if a method is
889 // static or non static
890 assert(compiler->is_c2() ||
891 _method->is_static() == (entry_point() == _verified_entry_point),
892 " entry points must be same for static methods and vice versa");
893 }
894
895 bool printnmethods = PrintNMethods
896 || CompilerOracle::should_print(_method)
897 || CompilerOracle::has_option_string(_method, "PrintNMethods");
898 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
899 print_nmethod(printnmethods);
900 }
901 }
902
903
904 // Print a short set of xml attributes to identify this nmethod. The
905 // output should be embedded in some other element.
906 void nmethod::log_identity(xmlStream* log) const {
907 log->print(" compile_id='%d'", compile_id());
908 const char* nm_kind = compile_kind();
909 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
910 if (compiler() != NULL) {
911 log->print(" compiler='%s'", compiler()->name());
912 }
913 if (TieredCompilation) {
914 log->print(" level='%d'", comp_level());
915 }
916 }
917
918
919 #define LOG_OFFSET(log, name) \
920 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
921 log->print(" " XSTR(name) "_offset='%d'" , \
922 (intptr_t)name##_begin() - (intptr_t)this)
923
924
925 void nmethod::log_new_nmethod() const {
926 if (LogCompilation && xtty != NULL) {
927 ttyLocker ttyl;
928 HandleMark hm;
929 xtty->begin_elem("nmethod");
930 log_identity(xtty);
931 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
932 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
933
934 LOG_OFFSET(xtty, relocation);
935 LOG_OFFSET(xtty, consts);
936 LOG_OFFSET(xtty, insts);
937 LOG_OFFSET(xtty, stub);
938 LOG_OFFSET(xtty, scopes_data);
939 LOG_OFFSET(xtty, scopes_pcs);
940 LOG_OFFSET(xtty, dependencies);
941 LOG_OFFSET(xtty, handler_table);
942 LOG_OFFSET(xtty, nul_chk_table);
943 LOG_OFFSET(xtty, oops);
944
945 xtty->method(method());
946 xtty->stamp();
947 xtty->end_elem();
948 }
949 }
950
951 #undef LOG_OFFSET
952
953
954 // Print out more verbose output usually for a newly created nmethod.
955 void nmethod::print_on(outputStream* st, const char* msg) const {
956 if (st != NULL) {
957 ttyLocker ttyl;
958 if (WizardMode) {
959 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
960 st->print_cr(" (" INTPTR_FORMAT ")", this);
961 } else {
962 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
963 }
964 }
965 }
966
967
968 void nmethod::print_nmethod(bool printmethod) {
969 ttyLocker ttyl; // keep the following output all in one block
970 if (xtty != NULL) {
971 xtty->begin_head("print_nmethod");
972 xtty->stamp();
973 xtty->end_head();
974 }
975 // print the header part first
976 print();
977 // then print the requested information
978 if (printmethod) {
979 print_code();
980 print_pcs();
981 if (oop_maps()) {
982 oop_maps()->print();
983 }
984 }
985 if (PrintDebugInfo) {
986 print_scopes();
987 }
988 if (PrintRelocations) {
989 print_relocations();
990 }
991 if (PrintDependencies) {
992 print_dependencies();
993 }
994 if (PrintExceptionHandlers) {
995 print_handler_table();
996 print_nul_chk_table();
997 }
998 if (xtty != NULL) {
999 xtty->tail("print_nmethod");
1000 }
1001 }
1002
1003
1004 // Promote one word from an assembly-time handle to a live embedded oop.
1005 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1006 if (handle == NULL ||
1007 // As a special case, IC oops are initialized to 1 or -1.
1008 handle == (jobject) Universe::non_oop_word()) {
1009 (*dest) = (oop) handle;
1010 } else {
1011 (*dest) = JNIHandles::resolve_non_null(handle);
1012 }
1013 }
1014
1015
1016 // Have to have the same name because it's called by a template
1017 void nmethod::copy_values(GrowableArray<jobject>* array) {
1018 int length = array->length();
1019 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1020 oop* dest = oops_begin();
1021 for (int index = 0 ; index < length; index++) {
1022 initialize_immediate_oop(&dest[index], array->at(index));
1023 }
1024
1025 // Now we can fix up all the oops in the code. We need to do this
1026 // in the code because the assembler uses jobjects as placeholders.
1027 // The code and relocations have already been initialized by the
1028 // CodeBlob constructor, so it is valid even at this early point to
1029 // iterate over relocations and patch the code.
1030 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1031 }
1032
1033 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1034 int length = array->length();
1035 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1036 Metadata** dest = metadata_begin();
1037 for (int index = 0 ; index < length; index++) {
1038 dest[index] = array->at(index);
1039 }
1040 }
1041
1042 bool nmethod::is_at_poll_return(address pc) {
1043 RelocIterator iter(this, pc, pc+1);
1044 while (iter.next()) {
1045 if (iter.type() == relocInfo::poll_return_type)
1046 return true;
1047 }
1048 return false;
1049 }
1050
1051
1052 bool nmethod::is_at_poll_or_poll_return(address pc) {
1053 RelocIterator iter(this, pc, pc+1);
1054 while (iter.next()) {
1055 relocInfo::relocType t = iter.type();
1056 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1057 return true;
1058 }
1059 return false;
1060 }
1061
1062
1063 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1064 // re-patch all oop-bearing instructions, just in case some oops moved
1065 RelocIterator iter(this, begin, end);
1066 while (iter.next()) {
1067 if (iter.type() == relocInfo::oop_type) {
1068 oop_Relocation* reloc = iter.oop_reloc();
1069 if (initialize_immediates && reloc->oop_is_immediate()) {
1070 oop* dest = reloc->oop_addr();
1071 initialize_immediate_oop(dest, (jobject) *dest);
1072 }
1073 // Refresh the oop-related bits of this instruction.
1074 reloc->fix_oop_relocation();
1075 } else if (iter.type() == relocInfo::metadata_type) {
1076 metadata_Relocation* reloc = iter.metadata_reloc();
1077 reloc->fix_metadata_relocation();
1078 }
1079
1080 // There must not be any interfering patches or breakpoints.
1081 assert(!(iter.type() == relocInfo::breakpoint_type
1082 && iter.breakpoint_reloc()->active()),
1083 "no active breakpoint");
1084 }
1085 }
1086
1087
1088 void nmethod::verify_oop_relocations() {
1089 // Ensure sure that the code matches the current oop values
1090 RelocIterator iter(this, NULL, NULL);
1091 while (iter.next()) {
1092 if (iter.type() == relocInfo::oop_type) {
1093 oop_Relocation* reloc = iter.oop_reloc();
1094 if (!reloc->oop_is_immediate()) {
1095 reloc->verify_oop_relocation();
1096 }
1097 }
1098 }
1099 }
1100
1101
1102 ScopeDesc* nmethod::scope_desc_at(address pc) {
1103 PcDesc* pd = pc_desc_at(pc);
1104 guarantee(pd != NULL, "scope must be present");
1105 return new ScopeDesc(this, pd->scope_decode_offset(),
1106 pd->obj_decode_offset(), pd->should_reexecute(),
1107 pd->return_oop());
1108 }
1109
1110
1111 void nmethod::clear_inline_caches() {
1112 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1113 if (is_zombie()) {
1114 return;
1115 }
1116
1117 RelocIterator iter(this);
1118 while (iter.next()) {
1119 iter.reloc()->clear_inline_cache();
1120 }
1121 }
1122
1123
1124 void nmethod::cleanup_inline_caches() {
1125
1126 assert_locked_or_safepoint(CompiledIC_lock);
1127
1128 // If the method is not entrant or zombie then a JMP is plastered over the
1129 // first few bytes. If an oop in the old code was there, that oop
1130 // should not get GC'd. Skip the first few bytes of oops on
1131 // not-entrant methods.
1132 address low_boundary = verified_entry_point();
1133 if (!is_in_use()) {
1134 low_boundary += NativeJump::instruction_size;
1135 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1136 // This means that the low_boundary is going to be a little too high.
1137 // This shouldn't matter, since oops of non-entrant methods are never used.
1138 // In fact, why are we bothering to look at oops in a non-entrant method??
1139 }
1140
1141 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1142 ResourceMark rm;
1143 RelocIterator iter(this, low_boundary);
1144 while(iter.next()) {
1145 switch(iter.type()) {
1146 case relocInfo::virtual_call_type:
1147 case relocInfo::opt_virtual_call_type: {
1148 CompiledIC *ic = CompiledIC_at(iter.reloc());
1149 // Ok, to lookup references to zombies here
1150 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1151 if( cb != NULL && cb->is_nmethod() ) {
1152 nmethod* nm = (nmethod*)cb;
1153 // Clean inline caches pointing to both zombie and not_entrant methods
1154 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1155 }
1156 break;
1157 }
1158 case relocInfo::static_call_type: {
1159 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1160 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1161 if( cb != NULL && cb->is_nmethod() ) {
1162 nmethod* nm = (nmethod*)cb;
1163 // Clean inline caches pointing to both zombie and not_entrant methods
1164 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1165 }
1166 break;
1167 }
1168 }
1169 }
1170 }
1171
1172 // This is a private interface with the sweeper.
1173 void nmethod::mark_as_seen_on_stack() {
1174 assert(is_not_entrant(), "must be a non-entrant method");
1175 // Set the traversal mark to ensure that the sweeper does 2
1176 // cleaning passes before moving to zombie.
1177 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1178 }
1179
1180 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1181 // there are no activations on the stack, not in use by the VM,
1182 // and not in use by the ServiceThread)
1183 bool nmethod::can_not_entrant_be_converted() {
1184 assert(is_not_entrant(), "must be a non-entrant method");
1185
1186 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1187 // count can be greater than the stack traversal count before it hits the
1188 // nmethod for the second time.
1189 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1190 !is_locked_by_vm();
1191 }
1192
1193 void nmethod::inc_decompile_count() {
1194 if (!is_compiled_by_c2()) return;
1195 // Could be gated by ProfileTraps, but do not bother...
1196 Method* m = method();
1197 if (m == NULL) return;
1198 MethodData* mdo = m->method_data();
1199 if (mdo == NULL) return;
1200 // There is a benign race here. See comments in methodData.hpp.
1201 mdo->inc_decompile_count();
1202 }
1203
1204 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1205
1206 post_compiled_method_unload();
1207
1208 // Since this nmethod is being unloaded, make sure that dependencies
1209 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1210 // indicate that this work is being done during a GC.
1211 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1212 assert(is_alive != NULL, "Should be non-NULL");
1213 // A non-NULL is_alive closure indicates that this is being called during GC.
1214 flush_dependencies(is_alive);
1215
1216 // Break cycle between nmethod & method
1217 if (TraceClassUnloading && WizardMode) {
1218 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1219 " unloadable], Method*(" INTPTR_FORMAT
1220 "), cause(" INTPTR_FORMAT ")",
1221 this, (address)_method, (address)cause);
1222 if (!Universe::heap()->is_gc_active())
1223 cause->klass()->print();
1224 }
1225 // Unlink the osr method, so we do not look this up again
1226 if (is_osr_method()) {
1227 invalidate_osr_method();
1228 }
1229 // If _method is already NULL the Method* is about to be unloaded,
1230 // so we don't have to break the cycle. Note that it is possible to
1231 // have the Method* live here, in case we unload the nmethod because
1232 // it is pointing to some oop (other than the Method*) being unloaded.
1233 if (_method != NULL) {
1234 // OSR methods point to the Method*, but the Method* does not
1235 // point back!
1236 if (_method->code() == this) {
1237 _method->clear_code(); // Break a cycle
1238 }
1239 _method = NULL; // Clear the method of this dead nmethod
1240 }
1241 // Make the class unloaded - i.e., change state and notify sweeper
1242 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1243 if (is_in_use()) {
1244 // Transitioning directly from live to unloaded -- so
1245 // we need to force a cache clean-up; remember this
1246 // for later on.
1247 CodeCache::set_needs_cache_clean(true);
1248 }
1249 _state = unloaded;
1250
1251 // Log the unloading.
1252 log_state_change();
1253
1254 // The Method* is gone at this point
1255 assert(_method == NULL, "Tautology");
1256
1257 set_osr_link(NULL);
1258 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1259 NMethodSweeper::notify(this);
1260 }
1261
1262 void nmethod::invalidate_osr_method() {
1263 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1264 // Remove from list of active nmethods
1265 if (method() != NULL)
1266 method()->method_holder()->remove_osr_nmethod(this);
1267 // Set entry as invalid
1268 _entry_bci = InvalidOSREntryBci;
1269 }
1270
1271 void nmethod::log_state_change() const {
1272 if (LogCompilation) {
1273 if (xtty != NULL) {
1274 ttyLocker ttyl; // keep the following output all in one block
1275 if (_state == unloaded) {
1276 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1277 os::current_thread_id());
1278 } else {
1279 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1280 os::current_thread_id(),
1281 (_state == zombie ? " zombie='1'" : ""));
1282 }
1283 log_identity(xtty);
1284 xtty->stamp();
1285 xtty->end_elem();
1286 }
1287 }
1288 if (PrintCompilation && _state != unloaded) {
1289 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1290 }
1291 }
1292
1293 // Common functionality for both make_not_entrant and make_zombie
1294 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1295 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1296 assert(!is_zombie(), "should not already be a zombie");
1297
1298 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1299 nmethodLocker nml(this);
1300 methodHandle the_method(method());
1301 No_Safepoint_Verifier nsv;
1302
1303 {
1304 // invalidate osr nmethod before acquiring the patching lock since
1305 // they both acquire leaf locks and we don't want a deadlock.
1306 // This logic is equivalent to the logic below for patching the
1307 // verified entry point of regular methods.
1308 if (is_osr_method()) {
1309 // this effectively makes the osr nmethod not entrant
1310 invalidate_osr_method();
1311 }
1312
1313 // Enter critical section. Does not block for safepoint.
1314 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1315
1316 if (_state == state) {
1317 // another thread already performed this transition so nothing
1318 // to do, but return false to indicate this.
1319 return false;
1320 }
1321
1322 // The caller can be calling the method statically or through an inline
1323 // cache call.
1324 if (!is_osr_method() && !is_not_entrant()) {
1325 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1326 SharedRuntime::get_handle_wrong_method_stub());
1327 }
1328
1329 if (is_in_use()) {
1330 // It's a true state change, so mark the method as decompiled.
1331 // Do it only for transition from alive.
1332 inc_decompile_count();
1333 }
1334
1335 // Change state
1336 _state = state;
1337
1338 // Log the transition once
1339 log_state_change();
1340
1341 // Remove nmethod from method.
1342 // We need to check if both the _code and _from_compiled_code_entry_point
1343 // refer to this nmethod because there is a race in setting these two fields
1344 // in Method* as seen in bugid 4947125.
1345 // If the vep() points to the zombie nmethod, the memory for the nmethod
1346 // could be flushed and the compiler and vtable stubs could still call
1347 // through it.
1348 if (method() != NULL && (method()->code() == this ||
1349 method()->from_compiled_entry() == verified_entry_point())) {
1350 HandleMark hm;
1351 method()->clear_code();
1352 }
1353
1354 if (state == not_entrant) {
1355 mark_as_seen_on_stack();
1356 }
1357
1358 } // leave critical region under Patching_lock
1359
1360 // When the nmethod becomes zombie it is no longer alive so the
1361 // dependencies must be flushed. nmethods in the not_entrant
1362 // state will be flushed later when the transition to zombie
1363 // happens or they get unloaded.
1364 if (state == zombie) {
1365 {
1366 // Flushing dependecies must be done before any possible
1367 // safepoint can sneak in, otherwise the oops used by the
1368 // dependency logic could have become stale.
1369 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1370 flush_dependencies(NULL);
1371 }
1372
1373 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1374 // event and it hasn't already been reported for this nmethod then
1375 // report it now. The event may have been reported earilier if the GC
1376 // marked it for unloading). JvmtiDeferredEventQueue support means
1377 // we no longer go to a safepoint here.
1378 post_compiled_method_unload();
1379
1380 #ifdef ASSERT
1381 // It's no longer safe to access the oops section since zombie
1382 // nmethods aren't scanned for GC.
1383 _oops_are_stale = true;
1384 #endif
1385 } else {
1386 assert(state == not_entrant, "other cases may need to be handled differently");
1387 }
1388
1389 if (TraceCreateZombies) {
1390 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1391 }
1392
1393 // Make sweeper aware that there is a zombie method that needs to be removed
1394 NMethodSweeper::notify(this);
1395
1396 return true;
1397 }
1398
1399 void nmethod::flush() {
1400 // Note that there are no valid oops in the nmethod anymore.
1401 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1402 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1403
1404 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1405 assert_locked_or_safepoint(CodeCache_lock);
1406
1407 // completely deallocate this method
1408 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1409 if (PrintMethodFlushing) {
1410 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1411 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
1412 }
1413
1414 // We need to deallocate any ExceptionCache data.
1415 // Note that we do not need to grab the nmethod lock for this, it
1416 // better be thread safe if we're disposing of it!
1417 ExceptionCache* ec = exception_cache();
1418 set_exception_cache(NULL);
1419 while(ec != NULL) {
1420 ExceptionCache* next = ec->next();
1421 delete ec;
1422 ec = next;
1423 }
1424
1425 if (on_scavenge_root_list()) {
1426 CodeCache::drop_scavenge_root_nmethod(this);
1427 }
1428
1429 if (is_speculatively_disconnected()) {
1430 CodeCache::remove_saved_code(this);
1431 }
1432
1433 #ifdef SHARK
1434 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1435 #endif // SHARK
1436
1437 ((CodeBlob*)(this))->flush();
1438
1439 CodeCache::free(this);
1440 }
1441
1442
1443 //
1444 // Notify all classes this nmethod is dependent on that it is no
1445 // longer dependent. This should only be called in two situations.
1446 // First, when a nmethod transitions to a zombie all dependents need
1447 // to be clear. Since zombification happens at a safepoint there's no
1448 // synchronization issues. The second place is a little more tricky.
1449 // During phase 1 of mark sweep class unloading may happen and as a
1450 // result some nmethods may get unloaded. In this case the flushing
1451 // of dependencies must happen during phase 1 since after GC any
1452 // dependencies in the unloaded nmethod won't be updated, so
1453 // traversing the dependency information in unsafe. In that case this
1454 // function is called with a non-NULL argument and this function only
1455 // notifies instanceKlasses that are reachable
1456
1457 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1458 assert_locked_or_safepoint(CodeCache_lock);
1459 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1460 "is_alive is non-NULL if and only if we are called during GC");
1461 if (!has_flushed_dependencies()) {
1462 set_has_flushed_dependencies();
1463 for (Dependencies::DepStream deps(this); deps.next(); ) {
1464 Klass* klass = deps.context_type();
1465 if (klass == NULL) continue; // ignore things like evol_method
1466
1467 // During GC the is_alive closure is non-NULL, and is used to
1468 // determine liveness of dependees that need to be updated.
1469 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1470 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1471 }
1472 }
1473 }
1474 }
1475
1476
1477 // If this oop is not live, the nmethod can be unloaded.
1478 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1479 assert(root != NULL, "just checking");
1480 oop obj = *root;
1481 if (obj == NULL || is_alive->do_object_b(obj)) {
1482 return false;
1483 }
1484
1485 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1486 // simply because one of its constant oops has gone dead.
1487 // No actual classes need to be unloaded in order for this to occur.
1488 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1489 make_unloaded(is_alive, obj);
1490 return true;
1491 }
1492
1493 // ------------------------------------------------------------------
1494 // post_compiled_method_load_event
1495 // new method for install_code() path
1496 // Transfer information from compilation to jvmti
1497 void nmethod::post_compiled_method_load_event() {
1498
1499 Method* moop = method();
1500 #ifndef USDT2
1501 HS_DTRACE_PROBE8(hotspot, compiled__method__load,
1502 moop->klass_name()->bytes(),
1503 moop->klass_name()->utf8_length(),
1504 moop->name()->bytes(),
1505 moop->name()->utf8_length(),
1506 moop->signature()->bytes(),
1507 moop->signature()->utf8_length(),
1508 insts_begin(), insts_size());
1509 #else /* USDT2 */
1510 HOTSPOT_COMPILED_METHOD_LOAD(
1511 (char *) moop->klass_name()->bytes(),
1512 moop->klass_name()->utf8_length(),
1513 (char *) moop->name()->bytes(),
1514 moop->name()->utf8_length(),
1515 (char *) moop->signature()->bytes(),
1516 moop->signature()->utf8_length(),
1517 insts_begin(), insts_size());
1518 #endif /* USDT2 */
1519
1520 if (JvmtiExport::should_post_compiled_method_load() ||
1521 JvmtiExport::should_post_compiled_method_unload()) {
1522 get_and_cache_jmethod_id();
1523 }
1524
1525 if (JvmtiExport::should_post_compiled_method_load()) {
1526 // Let the Service thread (which is a real Java thread) post the event
1527 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1528 JvmtiDeferredEventQueue::enqueue(
1529 JvmtiDeferredEvent::compiled_method_load_event(this));
1530 }
1531 }
1532
1533 jmethodID nmethod::get_and_cache_jmethod_id() {
1534 if (_jmethod_id == NULL) {
1535 // Cache the jmethod_id since it can no longer be looked up once the
1536 // method itself has been marked for unloading.
1537 _jmethod_id = method()->jmethod_id();
1538 }
1539 return _jmethod_id;
1540 }
1541
1542 void nmethod::post_compiled_method_unload() {
1543 if (unload_reported()) {
1544 // During unloading we transition to unloaded and then to zombie
1545 // and the unloading is reported during the first transition.
1546 return;
1547 }
1548
1549 assert(_method != NULL && !is_unloaded(), "just checking");
1550 DTRACE_METHOD_UNLOAD_PROBE(method());
1551
1552 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1553 // post the event. Sometime later this nmethod will be made a zombie
1554 // by the sweeper but the Method* will not be valid at that point.
1555 // If the _jmethod_id is null then no load event was ever requested
1556 // so don't bother posting the unload. The main reason for this is
1557 // that the jmethodID is a weak reference to the Method* so if
1558 // it's being unloaded there's no way to look it up since the weak
1559 // ref will have been cleared.
1560 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1561 assert(!unload_reported(), "already unloaded");
1562 JvmtiDeferredEvent event =
1563 JvmtiDeferredEvent::compiled_method_unload_event(this,
1564 _jmethod_id, insts_begin());
1565 if (SafepointSynchronize::is_at_safepoint()) {
1566 // Don't want to take the queueing lock. Add it as pending and
1567 // it will get enqueued later.
1568 JvmtiDeferredEventQueue::add_pending_event(event);
1569 } else {
1570 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1571 JvmtiDeferredEventQueue::enqueue(event);
1572 }
1573 }
1574
1575 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1576 // any time. As the nmethod is being unloaded now we mark it has
1577 // having the unload event reported - this will ensure that we don't
1578 // attempt to report the event in the unlikely scenario where the
1579 // event is enabled at the time the nmethod is made a zombie.
1580 set_unload_reported();
1581 }
1582
1583 // This is called at the end of the strong tracing/marking phase of a
1584 // GC to unload an nmethod if it contains otherwise unreachable
1585 // oops.
1586
1587 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1588 // Make sure the oop's ready to receive visitors
1589 assert(!is_zombie() && !is_unloaded(),
1590 "should not call follow on zombie or unloaded nmethod");
1591
1592 // If the method is not entrant then a JMP is plastered over the
1593 // first few bytes. If an oop in the old code was there, that oop
1594 // should not get GC'd. Skip the first few bytes of oops on
1595 // not-entrant methods.
1596 address low_boundary = verified_entry_point();
1597 if (is_not_entrant()) {
1598 low_boundary += NativeJump::instruction_size;
1599 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1600 // (See comment above.)
1601 }
1602
1603 // The RedefineClasses() API can cause the class unloading invariant
1604 // to no longer be true. See jvmtiExport.hpp for details.
1605 // Also, leave a debugging breadcrumb in local flag.
1606 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1607 if (a_class_was_redefined) {
1608 // This set of the unloading_occurred flag is done before the
1609 // call to post_compiled_method_unload() so that the unloading
1610 // of this nmethod is reported.
1611 unloading_occurred = true;
1612 }
1613
1614 // Exception cache
1615 ExceptionCache* ec = exception_cache();
1616 while (ec != NULL) {
1617 Klass* ex_klass = ec->exception_type();
1618 ExceptionCache* next_ec = ec->next();
1619 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
1620 remove_from_exception_cache(ec);
1621 }
1622 ec = next_ec;
1623 }
1624
1625 // If class unloading occurred we first iterate over all inline caches and
1626 // clear ICs where the cached oop is referring to an unloaded klass or method.
1627 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1628 // iteration below.
1629 if (unloading_occurred) {
1630 RelocIterator iter(this, low_boundary);
1631 while(iter.next()) {
1632 if (iter.type() == relocInfo::virtual_call_type) {
1633 CompiledIC *ic = CompiledIC_at(iter.reloc());
1634 if (ic->is_icholder_call()) {
1635 // The only exception is compiledICHolder oops which may
1636 // yet be marked below. (We check this further below).
1637 CompiledICHolder* cichk_oop = ic->cached_icholder();
1638 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1639 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1640 continue;
1641 }
1642 } else {
1643 Metadata* ic_oop = ic->cached_metadata();
1644 if (ic_oop != NULL) {
1645 if (ic_oop->is_klass()) {
1646 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1647 continue;
1648 }
1649 } else if (ic_oop->is_method()) {
1650 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1651 continue;
1652 }
1653 } else {
1654 ShouldNotReachHere();
1655 }
1656 }
1657 }
1658 ic->set_to_clean();
1659 }
1660 }
1661 }
1662
1663 // Compiled code
1664 {
1665 RelocIterator iter(this, low_boundary);
1666 while (iter.next()) {
1667 if (iter.type() == relocInfo::oop_type) {
1668 oop_Relocation* r = iter.oop_reloc();
1669 // In this loop, we must only traverse those oops directly embedded in
1670 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1671 assert(1 == (r->oop_is_immediate()) +
1672 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1673 "oop must be found in exactly one place");
1674 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1675 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1676 return;
1677 }
1678 }
1679 }
1680 }
1681 }
1682
1683
1684 // Scopes
1685 for (oop* p = oops_begin(); p < oops_end(); p++) {
1686 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1687 if (can_unload(is_alive, p, unloading_occurred)) {
1688 return;
1689 }
1690 }
1691
1692 // Ensure that all metadata is still alive
1693 verify_metadata_loaders(low_boundary, is_alive);
1694 }
1695
1696 #ifdef ASSERT
1697
1698 class CheckClass : AllStatic {
1699 static BoolObjectClosure* _is_alive;
1700
1701 // Check class_loader is alive for this bit of metadata.
1702 static void check_class(Metadata* md) {
1703 Klass* klass = NULL;
1704 if (md->is_klass()) {
1705 klass = ((Klass*)md);
1706 } else if (md->is_method()) {
1707 klass = ((Method*)md)->method_holder();
1708 } else if (md->is_methodData()) {
1709 klass = ((MethodData*)md)->method()->method_holder();
1710 } else {
1711 md->print();
1712 ShouldNotReachHere();
1713 }
1714 assert(klass->is_loader_alive(_is_alive), "must be alive");
1715 }
1716 public:
1717 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
1718 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
1719 _is_alive = is_alive;
1720 nm->metadata_do(check_class);
1721 }
1722 };
1723
1724 // This is called during a safepoint so can use static data
1725 BoolObjectClosure* CheckClass::_is_alive = NULL;
1726 #endif // ASSERT
1727
1728
1729 // Processing of oop references should have been sufficient to keep
1730 // all strong references alive. Any weak references should have been
1731 // cleared as well. Visit all the metadata and ensure that it's
1732 // really alive.
1733 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
1734 #ifdef ASSERT
1735 RelocIterator iter(this, low_boundary);
1736 while (iter.next()) {
1737 // static_stub_Relocations may have dangling references to
1738 // Method*s so trim them out here. Otherwise it looks like
1739 // compiled code is maintaining a link to dead metadata.
1740 address static_call_addr = NULL;
1741 if (iter.type() == relocInfo::opt_virtual_call_type) {
1742 CompiledIC* cic = CompiledIC_at(iter.reloc());
1743 if (!cic->is_call_to_interpreted()) {
1744 static_call_addr = iter.addr();
1745 }
1746 } else if (iter.type() == relocInfo::static_call_type) {
1747 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
1748 if (!csc->is_call_to_interpreted()) {
1749 static_call_addr = iter.addr();
1750 }
1751 }
1752 if (static_call_addr != NULL) {
1753 RelocIterator sciter(this, low_boundary);
1754 while (sciter.next()) {
1755 if (sciter.type() == relocInfo::static_stub_type &&
1756 sciter.static_stub_reloc()->static_call() == static_call_addr) {
1757 sciter.static_stub_reloc()->clear_inline_cache();
1758 }
1759 }
1760 }
1761 }
1762 // Check that the metadata embedded in the nmethod is alive
1763 CheckClass::do_check_class(is_alive, this);
1764 #endif
1765 }
1766
1767
1768 // Iterate over metadata calling this function. Used by RedefineClasses
1769 void nmethod::metadata_do(void f(Metadata*)) {
1770 address low_boundary = verified_entry_point();
1771 if (is_not_entrant()) {
1772 low_boundary += NativeJump::instruction_size;
1773 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1774 // (See comment above.)
1775 }
1776 {
1777 // Visit all immediate references that are embedded in the instruction stream.
1778 RelocIterator iter(this, low_boundary);
1779 while (iter.next()) {
1780 if (iter.type() == relocInfo::metadata_type ) {
1781 metadata_Relocation* r = iter.metadata_reloc();
1782 // In this lmetadata, we must only follow those metadatas directly embedded in
1783 // the code. Other metadatas (oop_index>0) are seen as part of
1784 // the metadata section below.
1785 assert(1 == (r->metadata_is_immediate()) +
1786 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1787 "metadata must be found in exactly one place");
1788 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1789 Metadata* md = r->metadata_value();
1790 f(md);
1791 }
1792 }
1793 }
1794 }
1795
1796 // Visit the metadata section
1797 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1798 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
1799 Metadata* md = *p;
1800 f(md);
1801 }
1802 // Call function Method*, not embedded in these other places.
1803 if (_method != NULL) f(_method);
1804 }
1805
1806
1807 // This method is called twice during GC -- once while
1808 // tracing the "active" nmethods on thread stacks during
1809 // the (strong) marking phase, and then again when walking
1810 // the code cache contents during the weak roots processing
1811 // phase. The two uses are distinguished by means of the
1812 // 'do_strong_roots_only' flag, which is true in the first
1813 // case. We want to walk the weak roots in the nmethod
1814 // only in the second case. The weak roots in the nmethod
1815 // are the oops in the ExceptionCache and the InlineCache
1816 // oops.
1817 void nmethod::oops_do(OopClosure* f, bool do_strong_roots_only) {
1818 // make sure the oops ready to receive visitors
1819 assert(!is_zombie() && !is_unloaded(),
1820 "should not call follow on zombie or unloaded nmethod");
1821
1822 // If the method is not entrant or zombie then a JMP is plastered over the
1823 // first few bytes. If an oop in the old code was there, that oop
1824 // should not get GC'd. Skip the first few bytes of oops on
1825 // not-entrant methods.
1826 address low_boundary = verified_entry_point();
1827 if (is_not_entrant()) {
1828 low_boundary += NativeJump::instruction_size;
1829 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1830 // (See comment above.)
1831 }
1832
1833 RelocIterator iter(this, low_boundary);
1834
1835 while (iter.next()) {
1836 if (iter.type() == relocInfo::oop_type ) {
1837 oop_Relocation* r = iter.oop_reloc();
1838 // In this loop, we must only follow those oops directly embedded in
1839 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1840 assert(1 == (r->oop_is_immediate()) +
1841 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1842 "oop must be found in exactly one place");
1843 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1844 f->do_oop(r->oop_addr());
1845 }
1846 }
1847 }
1848
1849 // Scopes
1850 // This includes oop constants not inlined in the code stream.
1851 for (oop* p = oops_begin(); p < oops_end(); p++) {
1852 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1853 f->do_oop(p);
1854 }
1855 }
1856
1857 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1858
1859 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1860
1861 // An nmethod is "marked" if its _mark_link is set non-null.
1862 // Even if it is the end of the linked list, it will have a non-null link value,
1863 // as long as it is on the list.
1864 // This code must be MP safe, because it is used from parallel GC passes.
1865 bool nmethod::test_set_oops_do_mark() {
1866 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1867 nmethod* observed_mark_link = _oops_do_mark_link;
1868 if (observed_mark_link == NULL) {
1869 // Claim this nmethod for this thread to mark.
1870 observed_mark_link = (nmethod*)
1871 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1872 if (observed_mark_link == NULL) {
1873
1874 // Atomically append this nmethod (now claimed) to the head of the list:
1875 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1876 for (;;) {
1877 nmethod* required_mark_nmethods = observed_mark_nmethods;
1878 _oops_do_mark_link = required_mark_nmethods;
1879 observed_mark_nmethods = (nmethod*)
1880 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1881 if (observed_mark_nmethods == required_mark_nmethods)
1882 break;
1883 }
1884 // Mark was clear when we first saw this guy.
1885 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
1886 return false;
1887 }
1888 }
1889 // On fall through, another racing thread marked this nmethod before we did.
1890 return true;
1891 }
1892
1893 void nmethod::oops_do_marking_prologue() {
1894 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
1895 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1896 // We use cmpxchg_ptr instead of regular assignment here because the user
1897 // may fork a bunch of threads, and we need them all to see the same state.
1898 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1899 guarantee(observed == NULL, "no races in this sequential code");
1900 }
1901
1902 void nmethod::oops_do_marking_epilogue() {
1903 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1904 nmethod* cur = _oops_do_mark_nmethods;
1905 while (cur != NMETHOD_SENTINEL) {
1906 assert(cur != NULL, "not NULL-terminated");
1907 nmethod* next = cur->_oops_do_mark_link;
1908 cur->_oops_do_mark_link = NULL;
1909 cur->fix_oop_relocations();
1910 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
1911 cur = next;
1912 }
1913 void* required = _oops_do_mark_nmethods;
1914 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1915 guarantee(observed == required, "no races in this sequential code");
1916 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
1917 }
1918
1919 class DetectScavengeRoot: public OopClosure {
1920 bool _detected_scavenge_root;
1921 public:
1922 DetectScavengeRoot() : _detected_scavenge_root(false)
1923 { NOT_PRODUCT(_print_nm = NULL); }
1924 bool detected_scavenge_root() { return _detected_scavenge_root; }
1925 virtual void do_oop(oop* p) {
1926 if ((*p) != NULL && (*p)->is_scavengable()) {
1927 NOT_PRODUCT(maybe_print(p));
1928 _detected_scavenge_root = true;
1929 }
1930 }
1931 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1932
1933 #ifndef PRODUCT
1934 nmethod* _print_nm;
1935 void maybe_print(oop* p) {
1936 if (_print_nm == NULL) return;
1937 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
1938 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
1939 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
1940 (intptr_t)(*p), (intptr_t)p);
1941 (*p)->print();
1942 }
1943 #endif //PRODUCT
1944 };
1945
1946 bool nmethod::detect_scavenge_root_oops() {
1947 DetectScavengeRoot detect_scavenge_root;
1948 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
1949 oops_do(&detect_scavenge_root);
1950 return detect_scavenge_root.detected_scavenge_root();
1951 }
1952
1953 // Method that knows how to preserve outgoing arguments at call. This method must be
1954 // called with a frame corresponding to a Java invoke
1955 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1956 #ifndef SHARK
1957 if (!method()->is_native()) {
1958 SimpleScopeDesc ssd(this, fr.pc());
1959 Bytecode_invoke call(ssd.method(), ssd.bci());
1960 bool has_receiver = call.has_receiver();
1961 bool has_appendix = call.has_appendix();
1962 Symbol* signature = call.signature();
1963 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
1964 }
1965 #endif // !SHARK
1966 }
1967
1968
1969 oop nmethod::embeddedOop_at(u_char* p) {
1970 RelocIterator iter(this, p, p + 1);
1971 while (iter.next())
1972 if (iter.type() == relocInfo::oop_type) {
1973 return iter.oop_reloc()->oop_value();
1974 }
1975 return NULL;
1976 }
1977
1978
1979 inline bool includes(void* p, void* from, void* to) {
1980 return from <= p && p < to;
1981 }
1982
1983
1984 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1985 assert(count >= 2, "must be sentinel values, at least");
1986
1987 #ifdef ASSERT
1988 // must be sorted and unique; we do a binary search in find_pc_desc()
1989 int prev_offset = pcs[0].pc_offset();
1990 assert(prev_offset == PcDesc::lower_offset_limit,
1991 "must start with a sentinel");
1992 for (int i = 1; i < count; i++) {
1993 int this_offset = pcs[i].pc_offset();
1994 assert(this_offset > prev_offset, "offsets must be sorted");
1995 prev_offset = this_offset;
1996 }
1997 assert(prev_offset == PcDesc::upper_offset_limit,
1998 "must end with a sentinel");
1999 #endif //ASSERT
2000
2001 // Search for MethodHandle invokes and tag the nmethod.
2002 for (int i = 0; i < count; i++) {
2003 if (pcs[i].is_method_handle_invoke()) {
2004 set_has_method_handle_invokes(true);
2005 break;
2006 }
2007 }
2008 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2009
2010 int size = count * sizeof(PcDesc);
2011 assert(scopes_pcs_size() >= size, "oob");
2012 memcpy(scopes_pcs_begin(), pcs, size);
2013
2014 // Adjust the final sentinel downward.
2015 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2016 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2017 last_pc->set_pc_offset(content_size() + 1);
2018 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2019 // Fill any rounding gaps with copies of the last record.
2020 last_pc[1] = last_pc[0];
2021 }
2022 // The following assert could fail if sizeof(PcDesc) is not
2023 // an integral multiple of oopSize (the rounding term).
2024 // If it fails, change the logic to always allocate a multiple
2025 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2026 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2027 }
2028
2029 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2030 assert(scopes_data_size() >= size, "oob");
2031 memcpy(scopes_data_begin(), buffer, size);
2032 }
2033
2034
2035 #ifdef ASSERT
2036 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2037 PcDesc* lower = nm->scopes_pcs_begin();
2038 PcDesc* upper = nm->scopes_pcs_end();
2039 lower += 1; // exclude initial sentinel
2040 PcDesc* res = NULL;
2041 for (PcDesc* p = lower; p < upper; p++) {
2042 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2043 if (match_desc(p, pc_offset, approximate)) {
2044 if (res == NULL)
2045 res = p;
2046 else
2047 res = (PcDesc*) badAddress;
2048 }
2049 }
2050 return res;
2051 }
2052 #endif
2053
2054
2055 // Finds a PcDesc with real-pc equal to "pc"
2056 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2057 address base_address = code_begin();
2058 if ((pc < base_address) ||
2059 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2060 return NULL; // PC is wildly out of range
2061 }
2062 int pc_offset = (int) (pc - base_address);
2063
2064 // Check the PcDesc cache if it contains the desired PcDesc
2065 // (This as an almost 100% hit rate.)
2066 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2067 if (res != NULL) {
2068 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2069 return res;
2070 }
2071
2072 // Fallback algorithm: quasi-linear search for the PcDesc
2073 // Find the last pc_offset less than the given offset.
2074 // The successor must be the required match, if there is a match at all.
2075 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2076 PcDesc* lower = scopes_pcs_begin();
2077 PcDesc* upper = scopes_pcs_end();
2078 upper -= 1; // exclude final sentinel
2079 if (lower >= upper) return NULL; // native method; no PcDescs at all
2080
2081 #define assert_LU_OK \
2082 /* invariant on lower..upper during the following search: */ \
2083 assert(lower->pc_offset() < pc_offset, "sanity"); \
2084 assert(upper->pc_offset() >= pc_offset, "sanity")
2085 assert_LU_OK;
2086
2087 // Use the last successful return as a split point.
2088 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2089 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2090 if (mid->pc_offset() < pc_offset) {
2091 lower = mid;
2092 } else {
2093 upper = mid;
2094 }
2095
2096 // Take giant steps at first (4096, then 256, then 16, then 1)
2097 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2098 const int RADIX = (1 << LOG2_RADIX);
2099 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2100 while ((mid = lower + step) < upper) {
2101 assert_LU_OK;
2102 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2103 if (mid->pc_offset() < pc_offset) {
2104 lower = mid;
2105 } else {
2106 upper = mid;
2107 break;
2108 }
2109 }
2110 assert_LU_OK;
2111 }
2112
2113 // Sneak up on the value with a linear search of length ~16.
2114 while (true) {
2115 assert_LU_OK;
2116 mid = lower + 1;
2117 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2118 if (mid->pc_offset() < pc_offset) {
2119 lower = mid;
2120 } else {
2121 upper = mid;
2122 break;
2123 }
2124 }
2125 #undef assert_LU_OK
2126
2127 if (match_desc(upper, pc_offset, approximate)) {
2128 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2129 _pc_desc_cache.add_pc_desc(upper);
2130 return upper;
2131 } else {
2132 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2133 return NULL;
2134 }
2135 }
2136
2137
2138 bool nmethod::check_all_dependencies() {
2139 bool found_check = false;
2140 // wholesale check of all dependencies
2141 for (Dependencies::DepStream deps(this); deps.next(); ) {
2142 if (deps.check_dependency() != NULL) {
2143 found_check = true;
2144 NOT_DEBUG(break);
2145 }
2146 }
2147 return found_check; // tell caller if we found anything
2148 }
2149
2150 bool nmethod::check_dependency_on(DepChange& changes) {
2151 // What has happened:
2152 // 1) a new class dependee has been added
2153 // 2) dependee and all its super classes have been marked
2154 bool found_check = false; // set true if we are upset
2155 for (Dependencies::DepStream deps(this); deps.next(); ) {
2156 // Evaluate only relevant dependencies.
2157 if (deps.spot_check_dependency_at(changes) != NULL) {
2158 found_check = true;
2159 NOT_DEBUG(break);
2160 }
2161 }
2162 return found_check;
2163 }
2164
2165 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2166 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2167 Array<Method*>* dependee_methods = dependee_ik->methods();
2168 for (Dependencies::DepStream deps(this); deps.next(); ) {
2169 if (deps.type() == Dependencies::evol_method) {
2170 Method* method = deps.method_argument(0);
2171 for (int j = 0; j < dependee_methods->length(); j++) {
2172 if (dependee_methods->at(j) == method) {
2173 // RC_TRACE macro has an embedded ResourceMark
2174 RC_TRACE(0x01000000,
2175 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2176 _method->method_holder()->external_name(),
2177 _method->name()->as_C_string(),
2178 _method->signature()->as_C_string(), compile_id(),
2179 method->method_holder()->external_name(),
2180 method->name()->as_C_string(),
2181 method->signature()->as_C_string()));
2182 if (TraceDependencies || LogCompilation)
2183 deps.log_dependency(dependee);
2184 return true;
2185 }
2186 }
2187 }
2188 }
2189 return false;
2190 }
2191
2192 // Called from mark_for_deoptimization, when dependee is invalidated.
2193 bool nmethod::is_dependent_on_method(Method* dependee) {
2194 for (Dependencies::DepStream deps(this); deps.next(); ) {
2195 if (deps.type() != Dependencies::evol_method)
2196 continue;
2197 Method* method = deps.method_argument(0);
2198 if (method == dependee) return true;
2199 }
2200 return false;
2201 }
2202
2203
2204 bool nmethod::is_patchable_at(address instr_addr) {
2205 assert(insts_contains(instr_addr), "wrong nmethod used");
2206 if (is_zombie()) {
2207 // a zombie may never be patched
2208 return false;
2209 }
2210 return true;
2211 }
2212
2213
2214 address nmethod::continuation_for_implicit_exception(address pc) {
2215 // Exception happened outside inline-cache check code => we are inside
2216 // an active nmethod => use cpc to determine a return address
2217 int exception_offset = pc - code_begin();
2218 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2219 #ifdef ASSERT
2220 if (cont_offset == 0) {
2221 Thread* thread = ThreadLocalStorage::get_thread_slow();
2222 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2223 HandleMark hm(thread);
2224 ResourceMark rm(thread);
2225 CodeBlob* cb = CodeCache::find_blob(pc);
2226 assert(cb != NULL && cb == this, "");
2227 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2228 print();
2229 method()->print_codes();
2230 print_code();
2231 print_pcs();
2232 }
2233 #endif
2234 if (cont_offset == 0) {
2235 // Let the normal error handling report the exception
2236 return NULL;
2237 }
2238 return code_begin() + cont_offset;
2239 }
2240
2241
2242
2243 void nmethod_init() {
2244 // make sure you didn't forget to adjust the filler fields
2245 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2246 }
2247
2248
2249 //-------------------------------------------------------------------------------------------
2250
2251
2252 // QQQ might we make this work from a frame??
2253 nmethodLocker::nmethodLocker(address pc) {
2254 CodeBlob* cb = CodeCache::find_blob(pc);
2255 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2256 _nm = (nmethod*)cb;
2257 lock_nmethod(_nm);
2258 }
2259
2260 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2261 // should pass zombie_ok == true.
2262 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2263 if (nm == NULL) return;
2264 Atomic::inc(&nm->_lock_count);
2265 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2266 }
2267
2268 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2269 if (nm == NULL) return;
2270 Atomic::dec(&nm->_lock_count);
2271 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2272 }
2273
2274
2275 // -----------------------------------------------------------------------------
2276 // nmethod::get_deopt_original_pc
2277 //
2278 // Return the original PC for the given PC if:
2279 // (a) the given PC belongs to a nmethod and
2280 // (b) it is a deopt PC
2281 address nmethod::get_deopt_original_pc(const frame* fr) {
2282 if (fr->cb() == NULL) return NULL;
2283
2284 nmethod* nm = fr->cb()->as_nmethod_or_null();
2285 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2286 return nm->get_original_pc(fr);
2287
2288 return NULL;
2289 }
2290
2291
2292 // -----------------------------------------------------------------------------
2293 // MethodHandle
2294
2295 bool nmethod::is_method_handle_return(address return_pc) {
2296 if (!has_method_handle_invokes()) return false;
2297 PcDesc* pd = pc_desc_at(return_pc);
2298 if (pd == NULL)
2299 return false;
2300 return pd->is_method_handle_invoke();
2301 }
2302
2303
2304 // -----------------------------------------------------------------------------
2305 // Verification
2306
2307 class VerifyOopsClosure: public OopClosure {
2308 nmethod* _nm;
2309 bool _ok;
2310 public:
2311 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2312 bool ok() { return _ok; }
2313 virtual void do_oop(oop* p) {
2314 if ((*p) == NULL || (*p)->is_oop()) return;
2315 if (_ok) {
2316 _nm->print_nmethod(true);
2317 _ok = false;
2318 }
2319 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2320 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2321 }
2322 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2323 };
2324
2325 void nmethod::verify() {
2326
2327 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2328 // seems odd.
2329
2330 if( is_zombie() || is_not_entrant() )
2331 return;
2332
2333 // Make sure all the entry points are correctly aligned for patching.
2334 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2335
2336 // assert(method()->is_oop(), "must be valid");
2337
2338 ResourceMark rm;
2339
2340 if (!CodeCache::contains(this)) {
2341 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2342 }
2343
2344 if(is_native_method() )
2345 return;
2346
2347 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2348 if (nm != this) {
2349 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2350 this));
2351 }
2352
2353 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2354 if (! p->verify(this)) {
2355 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2356 }
2357 }
2358
2359 VerifyOopsClosure voc(this);
2360 oops_do(&voc);
2361 assert(voc.ok(), "embedded oops must be OK");
2362 verify_scavenge_root_oops();
2363
2364 verify_scopes();
2365 }
2366
2367
2368 void nmethod::verify_interrupt_point(address call_site) {
2369 // This code does not work in release mode since
2370 // owns_lock only is available in debug mode.
2371 CompiledIC* ic = NULL;
2372 Thread *cur = Thread::current();
2373 if (CompiledIC_lock->owner() == cur ||
2374 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2375 SafepointSynchronize::is_at_safepoint())) {
2376 ic = CompiledIC_at(this, call_site);
2377 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2378 } else {
2379 MutexLocker ml_verify (CompiledIC_lock);
2380 ic = CompiledIC_at(this, call_site);
2381 }
2382 PcDesc* pd = pc_desc_at(ic->end_of_call());
2383 assert(pd != NULL, "PcDesc must exist");
2384 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2385 pd->obj_decode_offset(), pd->should_reexecute(),
2386 pd->return_oop());
2387 !sd->is_top(); sd = sd->sender()) {
2388 sd->verify();
2389 }
2390 }
2391
2392 void nmethod::verify_scopes() {
2393 if( !method() ) return; // Runtime stubs have no scope
2394 if (method()->is_native()) return; // Ignore stub methods.
2395 // iterate through all interrupt point
2396 // and verify the debug information is valid.
2397 RelocIterator iter((nmethod*)this);
2398 while (iter.next()) {
2399 address stub = NULL;
2400 switch (iter.type()) {
2401 case relocInfo::virtual_call_type:
2402 verify_interrupt_point(iter.addr());
2403 break;
2404 case relocInfo::opt_virtual_call_type:
2405 stub = iter.opt_virtual_call_reloc()->static_stub();
2406 verify_interrupt_point(iter.addr());
2407 break;
2408 case relocInfo::static_call_type:
2409 stub = iter.static_call_reloc()->static_stub();
2410 //verify_interrupt_point(iter.addr());
2411 break;
2412 case relocInfo::runtime_call_type:
2413 address destination = iter.reloc()->value();
2414 // Right now there is no way to find out which entries support
2415 // an interrupt point. It would be nice if we had this
2416 // information in a table.
2417 break;
2418 }
2419 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2420 }
2421 }
2422
2423
2424 // -----------------------------------------------------------------------------
2425 // Non-product code
2426 #ifndef PRODUCT
2427
2428 class DebugScavengeRoot: public OopClosure {
2429 nmethod* _nm;
2430 bool _ok;
2431 public:
2432 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2433 bool ok() { return _ok; }
2434 virtual void do_oop(oop* p) {
2435 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2436 if (_ok) {
2437 _nm->print_nmethod(true);
2438 _ok = false;
2439 }
2440 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2441 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2442 (*p)->print();
2443 }
2444 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2445 };
2446
2447 void nmethod::verify_scavenge_root_oops() {
2448 if (!on_scavenge_root_list()) {
2449 // Actually look inside, to verify the claim that it's clean.
2450 DebugScavengeRoot debug_scavenge_root(this);
2451 oops_do(&debug_scavenge_root);
2452 if (!debug_scavenge_root.ok())
2453 fatal("found an unadvertised bad scavengable oop in the code cache");
2454 }
2455 assert(scavenge_root_not_marked(), "");
2456 }
2457
2458 #endif // PRODUCT
2459
2460 // Printing operations
2461
2462 void nmethod::print() const {
2463 ResourceMark rm;
2464 ttyLocker ttyl; // keep the following output all in one block
2465
2466 tty->print("Compiled method ");
2467
2468 if (is_compiled_by_c1()) {
2469 tty->print("(c1) ");
2470 } else if (is_compiled_by_c2()) {
2471 tty->print("(c2) ");
2472 } else if (is_compiled_by_shark()) {
2473 tty->print("(shark) ");
2474 } else {
2475 tty->print("(nm) ");
2476 }
2477
2478 print_on(tty, NULL);
2479
2480 if (WizardMode) {
2481 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2482 tty->print(" for method " INTPTR_FORMAT , (address)method());
2483 tty->print(" { ");
2484 if (is_in_use()) tty->print("in_use ");
2485 if (is_not_entrant()) tty->print("not_entrant ");
2486 if (is_zombie()) tty->print("zombie ");
2487 if (is_unloaded()) tty->print("unloaded ");
2488 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2489 tty->print_cr("}:");
2490 }
2491 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2492 (address)this,
2493 (address)this + size(),
2494 size());
2495 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2496 relocation_begin(),
2497 relocation_end(),
2498 relocation_size());
2499 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2500 consts_begin(),
2501 consts_end(),
2502 consts_size());
2503 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2504 insts_begin(),
2505 insts_end(),
2506 insts_size());
2507 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2508 stub_begin(),
2509 stub_end(),
2510 stub_size());
2511 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2512 oops_begin(),
2513 oops_end(),
2514 oops_size());
2515 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2516 metadata_begin(),
2517 metadata_end(),
2518 metadata_size());
2519 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2520 scopes_data_begin(),
2521 scopes_data_end(),
2522 scopes_data_size());
2523 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2524 scopes_pcs_begin(),
2525 scopes_pcs_end(),
2526 scopes_pcs_size());
2527 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2528 dependencies_begin(),
2529 dependencies_end(),
2530 dependencies_size());
2531 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2532 handler_table_begin(),
2533 handler_table_end(),
2534 handler_table_size());
2535 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2536 nul_chk_table_begin(),
2537 nul_chk_table_end(),
2538 nul_chk_table_size());
2539 }
2540
2541 void nmethod::print_code() {
2542 HandleMark hm;
2543 ResourceMark m;
2544 Disassembler::decode(this);
2545 }
2546
2547
2548 #ifndef PRODUCT
2549
2550 void nmethod::print_scopes() {
2551 // Find the first pc desc for all scopes in the code and print it.
2552 ResourceMark rm;
2553 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2554 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2555 continue;
2556
2557 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2558 sd->print_on(tty, p);
2559 }
2560 }
2561
2562 void nmethod::print_dependencies() {
2563 ResourceMark rm;
2564 ttyLocker ttyl; // keep the following output all in one block
2565 tty->print_cr("Dependencies:");
2566 for (Dependencies::DepStream deps(this); deps.next(); ) {
2567 deps.print_dependency();
2568 Klass* ctxk = deps.context_type();
2569 if (ctxk != NULL) {
2570 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2571 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2572 }
2573 }
2574 deps.log_dependency(); // put it into the xml log also
2575 }
2576 }
2577
2578
2579 void nmethod::print_relocations() {
2580 ResourceMark m; // in case methods get printed via the debugger
2581 tty->print_cr("relocations:");
2582 RelocIterator iter(this);
2583 iter.print();
2584 if (UseRelocIndex) {
2585 jint* index_end = (jint*)relocation_end() - 1;
2586 jint index_size = *index_end;
2587 jint* index_start = (jint*)( (address)index_end - index_size );
2588 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2589 if (index_size > 0) {
2590 jint* ip;
2591 for (ip = index_start; ip+2 <= index_end; ip += 2)
2592 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2593 ip[0],
2594 ip[1],
2595 header_end()+ip[0],
2596 relocation_begin()-1+ip[1]);
2597 for (; ip < index_end; ip++)
2598 tty->print_cr(" (%d ?)", ip[0]);
2599 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip++);
2600 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2601 }
2602 }
2603 }
2604
2605
2606 void nmethod::print_pcs() {
2607 ResourceMark m; // in case methods get printed via debugger
2608 tty->print_cr("pc-bytecode offsets:");
2609 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2610 p->print(this);
2611 }
2612 }
2613
2614 #endif // PRODUCT
2615
2616 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2617 RelocIterator iter(this, begin, end);
2618 bool have_one = false;
2619 while (iter.next()) {
2620 have_one = true;
2621 switch (iter.type()) {
2622 case relocInfo::none: return "no_reloc";
2623 case relocInfo::oop_type: {
2624 stringStream st;
2625 oop_Relocation* r = iter.oop_reloc();
2626 oop obj = r->oop_value();
2627 st.print("oop(");
2628 if (obj == NULL) st.print("NULL");
2629 else obj->print_value_on(&st);
2630 st.print(")");
2631 return st.as_string();
2632 }
2633 case relocInfo::metadata_type: {
2634 stringStream st;
2635 metadata_Relocation* r = iter.metadata_reloc();
2636 Metadata* obj = r->metadata_value();
2637 st.print("metadata(");
2638 if (obj == NULL) st.print("NULL");
2639 else obj->print_value_on(&st);
2640 st.print(")");
2641 return st.as_string();
2642 }
2643 case relocInfo::virtual_call_type: return "virtual_call";
2644 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2645 case relocInfo::static_call_type: return "static_call";
2646 case relocInfo::static_stub_type: return "static_stub";
2647 case relocInfo::runtime_call_type: return "runtime_call";
2648 case relocInfo::external_word_type: return "external_word";
2649 case relocInfo::internal_word_type: return "internal_word";
2650 case relocInfo::section_word_type: return "section_word";
2651 case relocInfo::poll_type: return "poll";
2652 case relocInfo::poll_return_type: return "poll_return";
2653 case relocInfo::type_mask: return "type_bit_mask";
2654 }
2655 }
2656 return have_one ? "other" : NULL;
2657 }
2658
2659 // Return a the last scope in (begin..end]
2660 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2661 PcDesc* p = pc_desc_near(begin+1);
2662 if (p != NULL && p->real_pc(this) <= end) {
2663 return new ScopeDesc(this, p->scope_decode_offset(),
2664 p->obj_decode_offset(), p->should_reexecute(),
2665 p->return_oop());
2666 }
2667 return NULL;
2668 }
2669
2670 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2671 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2672 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2673 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2674 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2675 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2676
2677 if (has_method_handle_invokes())
2678 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
2679
2680 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
2681
2682 if (block_begin == entry_point()) {
2683 methodHandle m = method();
2684 if (m.not_null()) {
2685 stream->print(" # ");
2686 m->print_value_on(stream);
2687 stream->cr();
2688 }
2689 if (m.not_null() && !is_osr_method()) {
2690 ResourceMark rm;
2691 int sizeargs = m->size_of_parameters();
2692 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2693 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2694 {
2695 int sig_index = 0;
2696 if (!m->is_static())
2697 sig_bt[sig_index++] = T_OBJECT; // 'this'
2698 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2699 BasicType t = ss.type();
2700 sig_bt[sig_index++] = t;
2701 if (type2size[t] == 2) {
2702 sig_bt[sig_index++] = T_VOID;
2703 } else {
2704 assert(type2size[t] == 1, "size is 1 or 2");
2705 }
2706 }
2707 assert(sig_index == sizeargs, "");
2708 }
2709 const char* spname = "sp"; // make arch-specific?
2710 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2711 int stack_slot_offset = this->frame_size() * wordSize;
2712 int tab1 = 14, tab2 = 24;
2713 int sig_index = 0;
2714 int arg_index = (m->is_static() ? 0 : -1);
2715 bool did_old_sp = false;
2716 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2717 bool at_this = (arg_index == -1);
2718 bool at_old_sp = false;
2719 BasicType t = (at_this ? T_OBJECT : ss.type());
2720 assert(t == sig_bt[sig_index], "sigs in sync");
2721 if (at_this)
2722 stream->print(" # this: ");
2723 else
2724 stream->print(" # parm%d: ", arg_index);
2725 stream->move_to(tab1);
2726 VMReg fst = regs[sig_index].first();
2727 VMReg snd = regs[sig_index].second();
2728 if (fst->is_reg()) {
2729 stream->print("%s", fst->name());
2730 if (snd->is_valid()) {
2731 stream->print(":%s", snd->name());
2732 }
2733 } else if (fst->is_stack()) {
2734 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2735 if (offset == stack_slot_offset) at_old_sp = true;
2736 stream->print("[%s+0x%x]", spname, offset);
2737 } else {
2738 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2739 }
2740 stream->print(" ");
2741 stream->move_to(tab2);
2742 stream->print("= ");
2743 if (at_this) {
2744 m->method_holder()->print_value_on(stream);
2745 } else {
2746 bool did_name = false;
2747 if (!at_this && ss.is_object()) {
2748 Symbol* name = ss.as_symbol_or_null();
2749 if (name != NULL) {
2750 name->print_value_on(stream);
2751 did_name = true;
2752 }
2753 }
2754 if (!did_name)
2755 stream->print("%s", type2name(t));
2756 }
2757 if (at_old_sp) {
2758 stream->print(" (%s of caller)", spname);
2759 did_old_sp = true;
2760 }
2761 stream->cr();
2762 sig_index += type2size[t];
2763 arg_index += 1;
2764 if (!at_this) ss.next();
2765 }
2766 if (!did_old_sp) {
2767 stream->print(" # ");
2768 stream->move_to(tab1);
2769 stream->print("[%s+0x%x]", spname, stack_slot_offset);
2770 stream->print(" (%s of caller)", spname);
2771 stream->cr();
2772 }
2773 }
2774 }
2775 }
2776
2777 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2778 // First, find an oopmap in (begin, end].
2779 // We use the odd half-closed interval so that oop maps and scope descs
2780 // which are tied to the byte after a call are printed with the call itself.
2781 address base = code_begin();
2782 OopMapSet* oms = oop_maps();
2783 if (oms != NULL) {
2784 for (int i = 0, imax = oms->size(); i < imax; i++) {
2785 OopMap* om = oms->at(i);
2786 address pc = base + om->offset();
2787 if (pc > begin) {
2788 if (pc <= end) {
2789 st->move_to(column);
2790 st->print("; ");
2791 om->print_on(st);
2792 }
2793 break;
2794 }
2795 }
2796 }
2797
2798 // Print any debug info present at this pc.
2799 ScopeDesc* sd = scope_desc_in(begin, end);
2800 if (sd != NULL) {
2801 st->move_to(column);
2802 if (sd->bci() == SynchronizationEntryBCI) {
2803 st->print(";*synchronization entry");
2804 } else {
2805 if (sd->method() == NULL) {
2806 st->print("method is NULL");
2807 } else if (sd->method()->is_native()) {
2808 st->print("method is native");
2809 } else {
2810 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2811 st->print(";*%s", Bytecodes::name(bc));
2812 switch (bc) {
2813 case Bytecodes::_invokevirtual:
2814 case Bytecodes::_invokespecial:
2815 case Bytecodes::_invokestatic:
2816 case Bytecodes::_invokeinterface:
2817 {
2818 Bytecode_invoke invoke(sd->method(), sd->bci());
2819 st->print(" ");
2820 if (invoke.name() != NULL)
2821 invoke.name()->print_symbol_on(st);
2822 else
2823 st->print("<UNKNOWN>");
2824 break;
2825 }
2826 case Bytecodes::_getfield:
2827 case Bytecodes::_putfield:
2828 case Bytecodes::_getstatic:
2829 case Bytecodes::_putstatic:
2830 {
2831 Bytecode_field field(sd->method(), sd->bci());
2832 st->print(" ");
2833 if (field.name() != NULL)
2834 field.name()->print_symbol_on(st);
2835 else
2836 st->print("<UNKNOWN>");
2837 }
2838 }
2839 }
2840 }
2841
2842 // Print all scopes
2843 for (;sd != NULL; sd = sd->sender()) {
2844 st->move_to(column);
2845 st->print("; -");
2846 if (sd->method() == NULL) {
2847 st->print("method is NULL");
2848 } else {
2849 sd->method()->print_short_name(st);
2850 }
2851 int lineno = sd->method()->line_number_from_bci(sd->bci());
2852 if (lineno != -1) {
2853 st->print("@%d (line %d)", sd->bci(), lineno);
2854 } else {
2855 st->print("@%d", sd->bci());
2856 }
2857 st->cr();
2858 }
2859 }
2860
2861 // Print relocation information
2862 const char* str = reloc_string_for(begin, end);
2863 if (str != NULL) {
2864 if (sd != NULL) st->cr();
2865 st->move_to(column);
2866 st->print("; {%s}", str);
2867 }
2868 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2869 if (cont_offset != 0) {
2870 st->move_to(column);
2871 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
2872 }
2873
2874 }
2875
2876 #ifndef PRODUCT
2877
2878 void nmethod::print_value_on(outputStream* st) const {
2879 st->print("nmethod");
2880 print_on(st, NULL);
2881 }
2882
2883 void nmethod::print_calls(outputStream* st) {
2884 RelocIterator iter(this);
2885 while (iter.next()) {
2886 switch (iter.type()) {
2887 case relocInfo::virtual_call_type:
2888 case relocInfo::opt_virtual_call_type: {
2889 VerifyMutexLocker mc(CompiledIC_lock);
2890 CompiledIC_at(iter.reloc())->print();
2891 break;
2892 }
2893 case relocInfo::static_call_type:
2894 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2895 compiledStaticCall_at(iter.reloc())->print();
2896 break;
2897 }
2898 }
2899 }
2900
2901 void nmethod::print_handler_table() {
2902 ExceptionHandlerTable(this).print();
2903 }
2904
2905 void nmethod::print_nul_chk_table() {
2906 ImplicitExceptionTable(this).print(code_begin());
2907 }
2908
2909 void nmethod::print_statistics() {
2910 ttyLocker ttyl;
2911 if (xtty != NULL) xtty->head("statistics type='nmethod'");
2912 nmethod_stats.print_native_nmethod_stats();
2913 nmethod_stats.print_nmethod_stats();
2914 DebugInformationRecorder::print_statistics();
2915 nmethod_stats.print_pc_stats();
2916 Dependencies::print_statistics();
2917 if (xtty != NULL) xtty->tail("statistics");
2918 }
2919
2920 #endif // PRODUCT