1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "code/codeCache.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/dependencies.hpp"
29 #include "code/nmethod.hpp"
30 #include "code/scopeDesc.hpp"
31 #include "compiler/abstractCompiler.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/compileLog.hpp"
34 #include "compiler/compilerOracle.hpp"
35 #include "compiler/disassembler.hpp"
36 #include "interpreter/bytecode.hpp"
37 #include "oops/methodData.hpp"
38 #include "prims/jvmtiRedefineClassesTrace.hpp"
39 #include "prims/jvmtiImpl.hpp"
40 #include "runtime/sharedRuntime.hpp"
41 #include "runtime/sweeper.hpp"
42 #include "utilities/dtrace.hpp"
43 #include "utilities/events.hpp"
44 #include "utilities/xmlstream.hpp"
45 #ifdef SHARK
46 #include "shark/sharkCompiler.hpp"
47 #endif
48
49 #ifdef DTRACE_ENABLED
50
51 // Only bother with this argument setup if dtrace is available
52
53 #ifndef USDT2
54 HS_DTRACE_PROBE_DECL8(hotspot, compiled__method__load,
55 const char*, int, const char*, int, const char*, int, void*, size_t);
56
57 HS_DTRACE_PROBE_DECL6(hotspot, compiled__method__unload,
58 char*, int, char*, int, char*, int);
59
60 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
61 { \
62 Method* m = (method); \
63 if (m != NULL) { \
64 Symbol* klass_name = m->klass_name(); \
65 Symbol* name = m->name(); \
66 Symbol* signature = m->signature(); \
67 HS_DTRACE_PROBE6(hotspot, compiled__method__unload, \
68 klass_name->bytes(), klass_name->utf8_length(), \
69 name->bytes(), name->utf8_length(), \
70 signature->bytes(), signature->utf8_length()); \
71 } \
72 }
73 #else /* USDT2 */
74 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
75 { \
76 Method* m = (method); \
77 if (m != NULL) { \
78 Symbol* klass_name = m->klass_name(); \
79 Symbol* name = m->name(); \
80 Symbol* signature = m->signature(); \
81 HOTSPOT_COMPILED_METHOD_UNLOAD( \
82 (char *) klass_name->bytes(), klass_name->utf8_length(), \
83 (char *) name->bytes(), name->utf8_length(), \
84 (char *) signature->bytes(), signature->utf8_length()); \
85 } \
86 }
87 #endif /* USDT2 */
88
89 #else // ndef DTRACE_ENABLED
90
91 #define DTRACE_METHOD_UNLOAD_PROBE(method)
92
93 #endif
94
95 bool nmethod::is_compiled_by_c1() const {
96 if (compiler() == NULL) {
97 return false;
98 }
99 return compiler()->is_c1();
100 }
101 bool nmethod::is_compiled_by_c2() const {
102 if (compiler() == NULL) {
103 return false;
104 }
105 return compiler()->is_c2();
106 }
107 bool nmethod::is_compiled_by_shark() const {
108 if (compiler() == NULL) {
109 return false;
110 }
111 return compiler()->is_shark();
112 }
113
114
115
116 //---------------------------------------------------------------------------------
117 // NMethod statistics
118 // They are printed under various flags, including:
119 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
120 // (In the latter two cases, they like other stats are printed to the log only.)
121
122 #ifndef PRODUCT
123 // These variables are put into one block to reduce relocations
124 // and make it simpler to print from the debugger.
125 static
126 struct nmethod_stats_struct {
127 int nmethod_count;
128 int total_size;
129 int relocation_size;
130 int consts_size;
131 int insts_size;
132 int stub_size;
133 int scopes_data_size;
134 int scopes_pcs_size;
135 int dependencies_size;
136 int handler_table_size;
137 int nul_chk_table_size;
138 int oops_size;
139
140 void note_nmethod(nmethod* nm) {
141 nmethod_count += 1;
142 total_size += nm->size();
143 relocation_size += nm->relocation_size();
144 consts_size += nm->consts_size();
145 insts_size += nm->insts_size();
146 stub_size += nm->stub_size();
147 oops_size += nm->oops_size();
148 scopes_data_size += nm->scopes_data_size();
149 scopes_pcs_size += nm->scopes_pcs_size();
150 dependencies_size += nm->dependencies_size();
151 handler_table_size += nm->handler_table_size();
152 nul_chk_table_size += nm->nul_chk_table_size();
153 }
154 void print_nmethod_stats() {
155 if (nmethod_count == 0) return;
156 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
157 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
158 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
159 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
160 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size);
161 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
162 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
163 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
164 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
165 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
166 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
167 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
168 }
169
170 int native_nmethod_count;
171 int native_total_size;
172 int native_relocation_size;
173 int native_insts_size;
174 int native_oops_size;
175 void note_native_nmethod(nmethod* nm) {
176 native_nmethod_count += 1;
177 native_total_size += nm->size();
178 native_relocation_size += nm->relocation_size();
179 native_insts_size += nm->insts_size();
180 native_oops_size += nm->oops_size();
181 }
182 void print_native_nmethod_stats() {
183 if (native_nmethod_count == 0) return;
184 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
185 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
186 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
187 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size);
188 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
189 }
190
191 int pc_desc_resets; // number of resets (= number of caches)
192 int pc_desc_queries; // queries to nmethod::find_pc_desc
193 int pc_desc_approx; // number of those which have approximate true
194 int pc_desc_repeats; // number of _pc_descs[0] hits
195 int pc_desc_hits; // number of LRU cache hits
196 int pc_desc_tests; // total number of PcDesc examinations
197 int pc_desc_searches; // total number of quasi-binary search steps
198 int pc_desc_adds; // number of LUR cache insertions
199
200 void print_pc_stats() {
201 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
202 pc_desc_queries,
203 (double)(pc_desc_tests + pc_desc_searches)
204 / pc_desc_queries);
205 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
206 pc_desc_resets,
207 pc_desc_queries, pc_desc_approx,
208 pc_desc_repeats, pc_desc_hits,
209 pc_desc_tests, pc_desc_searches, pc_desc_adds);
210 }
211 } nmethod_stats;
212 #endif //PRODUCT
213
214
215 //---------------------------------------------------------------------------------
216
217
218 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
219 assert(pc != NULL, "Must be non null");
220 assert(exception.not_null(), "Must be non null");
221 assert(handler != NULL, "Must be non null");
222
223 _count = 0;
224 _exception_type = exception->klass();
225 _next = NULL;
226
227 add_address_and_handler(pc,handler);
228 }
229
230
231 address ExceptionCache::match(Handle exception, address pc) {
232 assert(pc != NULL,"Must be non null");
233 assert(exception.not_null(),"Must be non null");
234 if (exception->klass() == exception_type()) {
235 return (test_address(pc));
236 }
237
238 return NULL;
239 }
240
241
242 bool ExceptionCache::match_exception_with_space(Handle exception) {
243 assert(exception.not_null(),"Must be non null");
244 if (exception->klass() == exception_type() && count() < cache_size) {
245 return true;
246 }
247 return false;
248 }
249
250
251 address ExceptionCache::test_address(address addr) {
252 for (int i=0; i<count(); i++) {
253 if (pc_at(i) == addr) {
254 return handler_at(i);
255 }
256 }
257 return NULL;
258 }
259
260
261 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
262 if (test_address(addr) == handler) return true;
263 if (count() < cache_size) {
264 set_pc_at(count(),addr);
265 set_handler_at(count(), handler);
266 increment_count();
267 return true;
268 }
269 return false;
270 }
271
272
273 // private method for handling exception cache
274 // These methods are private, and used to manipulate the exception cache
275 // directly.
276 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
277 ExceptionCache* ec = exception_cache();
278 while (ec != NULL) {
279 if (ec->match_exception_with_space(exception)) {
280 return ec;
281 }
282 ec = ec->next();
283 }
284 return NULL;
285 }
286
287
288 //-----------------------------------------------------------------------------
289
290
291 // Helper used by both find_pc_desc methods.
292 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
293 NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
294 if (!approximate)
295 return pc->pc_offset() == pc_offset;
296 else
297 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
298 }
299
300 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
301 if (initial_pc_desc == NULL) {
302 _pc_descs[0] = NULL; // native method; no PcDescs at all
303 return;
304 }
305 NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
306 // reset the cache by filling it with benign (non-null) values
307 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
308 for (int i = 0; i < cache_size; i++)
309 _pc_descs[i] = initial_pc_desc;
310 }
311
312 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
313 NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
314 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
315
316 // Note: one might think that caching the most recently
317 // read value separately would be a win, but one would be
318 // wrong. When many threads are updating it, the cache
319 // line it's in would bounce between caches, negating
320 // any benefit.
321
322 // In order to prevent race conditions do not load cache elements
323 // repeatedly, but use a local copy:
324 PcDesc* res;
325
326 // Step one: Check the most recently added value.
327 res = _pc_descs[0];
328 if (res == NULL) return NULL; // native method; no PcDescs at all
329 if (match_desc(res, pc_offset, approximate)) {
330 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
331 return res;
332 }
333
334 // Step two: Check the rest of the LRU cache.
335 for (int i = 1; i < cache_size; ++i) {
336 res = _pc_descs[i];
337 if (res->pc_offset() < 0) break; // optimization: skip empty cache
338 if (match_desc(res, pc_offset, approximate)) {
339 NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
340 return res;
341 }
342 }
343
344 // Report failure.
345 return NULL;
346 }
347
348 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
349 NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
350 // Update the LRU cache by shifting pc_desc forward.
351 for (int i = 0; i < cache_size; i++) {
352 PcDesc* next = _pc_descs[i];
353 _pc_descs[i] = pc_desc;
354 pc_desc = next;
355 }
356 }
357
358 // adjust pcs_size so that it is a multiple of both oopSize and
359 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
360 // of oopSize, then 2*sizeof(PcDesc) is)
361 static int adjust_pcs_size(int pcs_size) {
362 int nsize = round_to(pcs_size, oopSize);
363 if ((nsize % sizeof(PcDesc)) != 0) {
364 nsize = pcs_size + sizeof(PcDesc);
365 }
366 assert((nsize % oopSize) == 0, "correct alignment");
367 return nsize;
368 }
369
370 //-----------------------------------------------------------------------------
371
372
373 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
374 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
375 assert(new_entry != NULL,"Must be non null");
376 assert(new_entry->next() == NULL, "Must be null");
377
378 if (exception_cache() != NULL) {
379 new_entry->set_next(exception_cache());
380 }
381 set_exception_cache(new_entry);
382 }
383
384 void nmethod::remove_from_exception_cache(ExceptionCache* ec) {
385 ExceptionCache* prev = NULL;
386 ExceptionCache* curr = exception_cache();
387 assert(curr != NULL, "nothing to remove");
388 // find the previous and next entry of ec
389 while (curr != ec) {
390 prev = curr;
391 curr = curr->next();
392 assert(curr != NULL, "ExceptionCache not found");
393 }
394 // now: curr == ec
395 ExceptionCache* next = curr->next();
396 if (prev == NULL) {
397 set_exception_cache(next);
398 } else {
399 prev->set_next(next);
400 }
401 delete curr;
402 }
403
404
405 // public method for accessing the exception cache
406 // These are the public access methods.
407 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
408 // We never grab a lock to read the exception cache, so we may
409 // have false negatives. This is okay, as it can only happen during
410 // the first few exception lookups for a given nmethod.
411 ExceptionCache* ec = exception_cache();
412 while (ec != NULL) {
413 address ret_val;
414 if ((ret_val = ec->match(exception,pc)) != NULL) {
415 return ret_val;
416 }
417 ec = ec->next();
418 }
419 return NULL;
420 }
421
422
423 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
424 // There are potential race conditions during exception cache updates, so we
425 // must own the ExceptionCache_lock before doing ANY modifications. Because
426 // we don't lock during reads, it is possible to have several threads attempt
427 // to update the cache with the same data. We need to check for already inserted
428 // copies of the current data before adding it.
429
430 MutexLocker ml(ExceptionCache_lock);
431 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
432
433 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
434 target_entry = new ExceptionCache(exception,pc,handler);
435 add_exception_cache_entry(target_entry);
436 }
437 }
438
439
440 //-------------end of code for ExceptionCache--------------
441
442
443 int nmethod::total_size() const {
444 return
445 consts_size() +
446 insts_size() +
447 stub_size() +
448 scopes_data_size() +
449 scopes_pcs_size() +
450 handler_table_size() +
451 nul_chk_table_size();
452 }
453
454 const char* nmethod::compile_kind() const {
455 if (is_osr_method()) return "osr";
456 if (method() != NULL && is_native_method()) return "c2n";
457 return NULL;
458 }
459
460 // Fill in default values for various flag fields
461 void nmethod::init_defaults() {
462 _state = alive;
463 _marked_for_reclamation = 0;
464 _has_flushed_dependencies = 0;
465 _has_unsafe_access = 0;
466 _has_method_handle_invokes = 0;
467 _lazy_critical_native = 0;
468 _has_wide_vectors = 0;
469 _marked_for_deoptimization = 0;
470 _lock_count = 0;
471 _stack_traversal_mark = 0;
472 _unload_reported = false; // jvmti state
473
474 #ifdef ASSERT
475 _oops_are_stale = false;
476 #endif
477
478 _oops_do_mark_link = NULL;
479 _jmethod_id = NULL;
480 _osr_link = NULL;
481 _scavenge_root_link = NULL;
482 _scavenge_root_state = 0;
483 _compiler = NULL;
484
485 #ifdef HAVE_DTRACE_H
486 _trap_offset = 0;
487 #endif // def HAVE_DTRACE_H
488 }
489
490 nmethod* nmethod::new_native_nmethod(methodHandle method,
491 int compile_id,
492 CodeBuffer *code_buffer,
493 int vep_offset,
494 int frame_complete,
495 int frame_size,
496 ByteSize basic_lock_owner_sp_offset,
497 ByteSize basic_lock_sp_offset,
498 OopMapSet* oop_maps) {
499 code_buffer->finalize_oop_references(method);
500 // create nmethod
501 nmethod* nm = NULL;
502 {
503 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
504 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
505 CodeOffsets offsets;
506 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
507 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
508 nm = new (native_nmethod_size) nmethod(method(), native_nmethod_size,
509 compile_id, &offsets,
510 code_buffer, frame_size,
511 basic_lock_owner_sp_offset,
512 basic_lock_sp_offset, oop_maps);
513 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm));
514 if (PrintAssembly && nm != NULL) {
515 Disassembler::decode(nm);
516 }
517 }
518 // verify nmethod
519 debug_only(if (nm) nm->verify();) // might block
520
521 if (nm != NULL) {
522 nm->log_new_nmethod();
523 }
524
525 return nm;
526 }
527
528 #ifdef HAVE_DTRACE_H
529 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
530 CodeBuffer *code_buffer,
531 int vep_offset,
532 int trap_offset,
533 int frame_complete,
534 int frame_size) {
535 code_buffer->finalize_oop_references(method);
536 // create nmethod
537 nmethod* nm = NULL;
538 {
539 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
540 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
541 CodeOffsets offsets;
542 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
543 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
544 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
545
546 nm = new (nmethod_size) nmethod(method(), nmethod_size,
547 &offsets, code_buffer, frame_size);
548
549 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
550 if (PrintAssembly && nm != NULL) {
551 Disassembler::decode(nm);
552 }
553 }
554 // verify nmethod
555 debug_only(if (nm) nm->verify();) // might block
556
557 if (nm != NULL) {
558 nm->log_new_nmethod();
559 }
560
561 return nm;
562 }
563
564 #endif // def HAVE_DTRACE_H
565
566 nmethod* nmethod::new_nmethod(methodHandle method,
567 int compile_id,
568 int entry_bci,
569 CodeOffsets* offsets,
570 int orig_pc_offset,
571 DebugInformationRecorder* debug_info,
572 Dependencies* dependencies,
573 CodeBuffer* code_buffer, int frame_size,
574 OopMapSet* oop_maps,
575 ExceptionHandlerTable* handler_table,
576 ImplicitExceptionTable* nul_chk_table,
577 AbstractCompiler* compiler,
578 int comp_level
579 )
580 {
581 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
582 code_buffer->finalize_oop_references(method);
583 // create nmethod
584 nmethod* nm = NULL;
585 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
586 int nmethod_size =
587 allocation_size(code_buffer, sizeof(nmethod))
588 + adjust_pcs_size(debug_info->pcs_size())
589 + round_to(dependencies->size_in_bytes() , oopSize)
590 + round_to(handler_table->size_in_bytes(), oopSize)
591 + round_to(nul_chk_table->size_in_bytes(), oopSize)
592 + round_to(debug_info->data_size() , oopSize);
593
594 nm = new (nmethod_size)
595 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
596 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
597 oop_maps,
598 handler_table,
599 nul_chk_table,
600 compiler,
601 comp_level);
602
603 if (nm != NULL) {
604 // To make dependency checking during class loading fast, record
605 // the nmethod dependencies in the classes it is dependent on.
606 // This allows the dependency checking code to simply walk the
607 // class hierarchy above the loaded class, checking only nmethods
608 // which are dependent on those classes. The slow way is to
609 // check every nmethod for dependencies which makes it linear in
610 // the number of methods compiled. For applications with a lot
611 // classes the slow way is too slow.
612 for (Dependencies::DepStream deps(nm); deps.next(); ) {
613 Klass* klass = deps.context_type();
614 if (klass == NULL) {
615 continue; // ignore things like evol_method
616 }
617
618 // record this nmethod as dependent on this klass
619 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
620 }
621 }
622 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
623 if (PrintAssembly && nm != NULL) {
624 Disassembler::decode(nm);
625 }
626 }
627
628 // verify nmethod
629 debug_only(if (nm) nm->verify();) // might block
630
631 if (nm != NULL) {
632 nm->log_new_nmethod();
633 }
634
635 // done
636 return nm;
637 }
638
639
640 // For native wrappers
641 nmethod::nmethod(
642 Method* method,
643 int nmethod_size,
644 int compile_id,
645 CodeOffsets* offsets,
646 CodeBuffer* code_buffer,
647 int frame_size,
648 ByteSize basic_lock_owner_sp_offset,
649 ByteSize basic_lock_sp_offset,
650 OopMapSet* oop_maps )
651 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
652 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
653 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
654 _native_basic_lock_sp_offset(basic_lock_sp_offset)
655 {
656 {
657 debug_only(No_Safepoint_Verifier nsv;)
658 assert_locked_or_safepoint(CodeCache_lock);
659
660 init_defaults();
661 _method = method;
662 _entry_bci = InvocationEntryBci;
663 // We have no exception handler or deopt handler make the
664 // values something that will never match a pc like the nmethod vtable entry
665 _exception_offset = 0;
666 _deoptimize_offset = 0;
667 _deoptimize_mh_offset = 0;
668 _orig_pc_offset = 0;
669
670 _consts_offset = data_offset();
671 _stub_offset = data_offset();
672 _oops_offset = data_offset();
673 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
674 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
675 _scopes_pcs_offset = _scopes_data_offset;
676 _dependencies_offset = _scopes_pcs_offset;
677 _handler_table_offset = _dependencies_offset;
678 _nul_chk_table_offset = _handler_table_offset;
679 _nmethod_end_offset = _nul_chk_table_offset;
680 _compile_id = compile_id;
681 _comp_level = CompLevel_none;
682 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
683 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
684 _osr_entry_point = NULL;
685 _exception_cache = NULL;
686 _pc_desc_cache.reset_to(NULL);
687 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
688
689 code_buffer->copy_values_to(this);
690 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
691 CodeCache::add_scavenge_root_nmethod(this);
692 Universe::heap()->register_nmethod(this);
693 }
694 debug_only(verify_scavenge_root_oops());
695 CodeCache::commit(this);
696 }
697
698 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
699 ttyLocker ttyl; // keep the following output all in one block
700 // This output goes directly to the tty, not the compiler log.
701 // To enable tools to match it up with the compilation activity,
702 // be sure to tag this tty output with the compile ID.
703 if (xtty != NULL) {
704 xtty->begin_head("print_native_nmethod");
705 xtty->method(_method);
706 xtty->stamp();
707 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
708 }
709 // print the header part first
710 print();
711 // then print the requested information
712 if (PrintNativeNMethods) {
713 print_code();
714 if (oop_maps != NULL) {
715 oop_maps->print();
716 }
717 }
718 if (PrintRelocations) {
719 print_relocations();
720 }
721 if (xtty != NULL) {
722 xtty->tail("print_native_nmethod");
723 }
724 }
725 }
726
727 // For dtrace wrappers
728 #ifdef HAVE_DTRACE_H
729 nmethod::nmethod(
730 Method* method,
731 int nmethod_size,
732 CodeOffsets* offsets,
733 CodeBuffer* code_buffer,
734 int frame_size)
735 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
736 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
737 _native_receiver_sp_offset(in_ByteSize(-1)),
738 _native_basic_lock_sp_offset(in_ByteSize(-1))
739 {
740 {
741 debug_only(No_Safepoint_Verifier nsv;)
742 assert_locked_or_safepoint(CodeCache_lock);
743
744 init_defaults();
745 _method = method;
746 _entry_bci = InvocationEntryBci;
747 // We have no exception handler or deopt handler make the
748 // values something that will never match a pc like the nmethod vtable entry
749 _exception_offset = 0;
750 _deoptimize_offset = 0;
751 _deoptimize_mh_offset = 0;
752 _unwind_handler_offset = -1;
753 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
754 _orig_pc_offset = 0;
755 _consts_offset = data_offset();
756 _stub_offset = data_offset();
757 _oops_offset = data_offset();
758 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
759 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
760 _scopes_pcs_offset = _scopes_data_offset;
761 _dependencies_offset = _scopes_pcs_offset;
762 _handler_table_offset = _dependencies_offset;
763 _nul_chk_table_offset = _handler_table_offset;
764 _nmethod_end_offset = _nul_chk_table_offset;
765 _compile_id = 0; // default
766 _comp_level = CompLevel_none;
767 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
768 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
769 _osr_entry_point = NULL;
770 _exception_cache = NULL;
771 _pc_desc_cache.reset_to(NULL);
772 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
773
774 code_buffer->copy_values_to(this);
775 debug_only(verify_scavenge_root_oops());
776 CodeCache::commit(this);
777 }
778
779 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
780 ttyLocker ttyl; // keep the following output all in one block
781 // This output goes directly to the tty, not the compiler log.
782 // To enable tools to match it up with the compilation activity,
783 // be sure to tag this tty output with the compile ID.
784 if (xtty != NULL) {
785 xtty->begin_head("print_dtrace_nmethod");
786 xtty->method(_method);
787 xtty->stamp();
788 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
789 }
790 // print the header part first
791 print();
792 // then print the requested information
793 if (PrintNMethods) {
794 print_code();
795 }
796 if (PrintRelocations) {
797 print_relocations();
798 }
799 if (xtty != NULL) {
800 xtty->tail("print_dtrace_nmethod");
801 }
802 }
803 }
804 #endif // def HAVE_DTRACE_H
805
806 void* nmethod::operator new(size_t size, int nmethod_size) throw() {
807 // Not critical, may return null if there is too little continuous memory
808 return CodeCache::allocate(nmethod_size);
809 }
810
811 nmethod::nmethod(
812 Method* method,
813 int nmethod_size,
814 int compile_id,
815 int entry_bci,
816 CodeOffsets* offsets,
817 int orig_pc_offset,
818 DebugInformationRecorder* debug_info,
819 Dependencies* dependencies,
820 CodeBuffer *code_buffer,
821 int frame_size,
822 OopMapSet* oop_maps,
823 ExceptionHandlerTable* handler_table,
824 ImplicitExceptionTable* nul_chk_table,
825 AbstractCompiler* compiler,
826 int comp_level
827 )
828 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
829 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
830 _native_receiver_sp_offset(in_ByteSize(-1)),
831 _native_basic_lock_sp_offset(in_ByteSize(-1))
832 {
833 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
834 {
835 debug_only(No_Safepoint_Verifier nsv;)
836 assert_locked_or_safepoint(CodeCache_lock);
837
838 init_defaults();
839 _method = method;
840 _entry_bci = entry_bci;
841 _compile_id = compile_id;
842 _comp_level = comp_level;
843 _compiler = compiler;
844 _orig_pc_offset = orig_pc_offset;
845 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
846
847 // Section offsets
848 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
849 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
850
851 // Exception handler and deopt handler are in the stub section
852 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
853 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
854 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
855 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
856 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
857 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
858 } else {
859 _deoptimize_mh_offset = -1;
860 }
861 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
862 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
863 } else {
864 _unwind_handler_offset = -1;
865 }
866
867 _oops_offset = data_offset();
868 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
869 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
870
871 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
872 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
873 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
874 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
875 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
876
877 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
878 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
879 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
880 _exception_cache = NULL;
881 _pc_desc_cache.reset_to(scopes_pcs_begin());
882
883 // Copy contents of ScopeDescRecorder to nmethod
884 code_buffer->copy_values_to(this);
885 debug_info->copy_to(this);
886 dependencies->copy_to(this);
887 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
888 CodeCache::add_scavenge_root_nmethod(this);
889 Universe::heap()->register_nmethod(this);
890 }
891 debug_only(verify_scavenge_root_oops());
892
893 CodeCache::commit(this);
894
895 // Copy contents of ExceptionHandlerTable to nmethod
896 handler_table->copy_to(this);
897 nul_chk_table->copy_to(this);
898
899 // we use the information of entry points to find out if a method is
900 // static or non static
901 assert(compiler->is_c2() ||
902 _method->is_static() == (entry_point() == _verified_entry_point),
903 " entry points must be same for static methods and vice versa");
904 }
905
906 bool printnmethods = PrintNMethods
907 || CompilerOracle::should_print(_method)
908 || CompilerOracle::has_option_string(_method, "PrintNMethods");
909 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
910 print_nmethod(printnmethods);
911 }
912 }
913
914
915 // Print a short set of xml attributes to identify this nmethod. The
916 // output should be embedded in some other element.
917 void nmethod::log_identity(xmlStream* log) const {
918 log->print(" compile_id='%d'", compile_id());
919 const char* nm_kind = compile_kind();
920 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
921 if (compiler() != NULL) {
922 log->print(" compiler='%s'", compiler()->name());
923 }
924 if (TieredCompilation) {
925 log->print(" level='%d'", comp_level());
926 }
927 }
928
929
930 #define LOG_OFFSET(log, name) \
931 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
932 log->print(" " XSTR(name) "_offset='%d'" , \
933 (intptr_t)name##_begin() - (intptr_t)this)
934
935
936 void nmethod::log_new_nmethod() const {
937 if (LogCompilation && xtty != NULL) {
938 ttyLocker ttyl;
939 HandleMark hm;
940 xtty->begin_elem("nmethod");
941 log_identity(xtty);
942 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
943 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
944
945 LOG_OFFSET(xtty, relocation);
946 LOG_OFFSET(xtty, consts);
947 LOG_OFFSET(xtty, insts);
948 LOG_OFFSET(xtty, stub);
949 LOG_OFFSET(xtty, scopes_data);
950 LOG_OFFSET(xtty, scopes_pcs);
951 LOG_OFFSET(xtty, dependencies);
952 LOG_OFFSET(xtty, handler_table);
953 LOG_OFFSET(xtty, nul_chk_table);
954 LOG_OFFSET(xtty, oops);
955
956 xtty->method(method());
957 xtty->stamp();
958 xtty->end_elem();
959 }
960 }
961
962 #undef LOG_OFFSET
963
964
965 // Print out more verbose output usually for a newly created nmethod.
966 void nmethod::print_on(outputStream* st, const char* msg) const {
967 if (st != NULL) {
968 ttyLocker ttyl;
969 if (WizardMode) {
970 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
971 st->print_cr(" (" INTPTR_FORMAT ")", this);
972 } else {
973 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
974 }
975 }
976 }
977
978
979 void nmethod::print_nmethod(bool printmethod) {
980 ttyLocker ttyl; // keep the following output all in one block
981 if (xtty != NULL) {
982 xtty->begin_head("print_nmethod");
983 xtty->stamp();
984 xtty->end_head();
985 }
986 // print the header part first
987 print();
988 // then print the requested information
989 if (printmethod) {
990 print_code();
991 print_pcs();
992 if (oop_maps()) {
993 oop_maps()->print();
994 }
995 }
996 if (PrintDebugInfo) {
997 print_scopes();
998 }
999 if (PrintRelocations) {
1000 print_relocations();
1001 }
1002 if (PrintDependencies) {
1003 print_dependencies();
1004 }
1005 if (PrintExceptionHandlers) {
1006 print_handler_table();
1007 print_nul_chk_table();
1008 }
1009 if (xtty != NULL) {
1010 xtty->tail("print_nmethod");
1011 }
1012 }
1013
1014
1015 // Promote one word from an assembly-time handle to a live embedded oop.
1016 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1017 if (handle == NULL ||
1018 // As a special case, IC oops are initialized to 1 or -1.
1019 handle == (jobject) Universe::non_oop_word()) {
1020 (*dest) = (oop) handle;
1021 } else {
1022 (*dest) = JNIHandles::resolve_non_null(handle);
1023 }
1024 }
1025
1026
1027 // Have to have the same name because it's called by a template
1028 void nmethod::copy_values(GrowableArray<jobject>* array) {
1029 int length = array->length();
1030 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1031 oop* dest = oops_begin();
1032 for (int index = 0 ; index < length; index++) {
1033 initialize_immediate_oop(&dest[index], array->at(index));
1034 }
1035
1036 // Now we can fix up all the oops in the code. We need to do this
1037 // in the code because the assembler uses jobjects as placeholders.
1038 // The code and relocations have already been initialized by the
1039 // CodeBlob constructor, so it is valid even at this early point to
1040 // iterate over relocations and patch the code.
1041 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1042 }
1043
1044 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1045 int length = array->length();
1046 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1047 Metadata** dest = metadata_begin();
1048 for (int index = 0 ; index < length; index++) {
1049 dest[index] = array->at(index);
1050 }
1051 }
1052
1053 bool nmethod::is_at_poll_return(address pc) {
1054 RelocIterator iter(this, pc, pc+1);
1055 while (iter.next()) {
1056 if (iter.type() == relocInfo::poll_return_type)
1057 return true;
1058 }
1059 return false;
1060 }
1061
1062
1063 bool nmethod::is_at_poll_or_poll_return(address pc) {
1064 RelocIterator iter(this, pc, pc+1);
1065 while (iter.next()) {
1066 relocInfo::relocType t = iter.type();
1067 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1068 return true;
1069 }
1070 return false;
1071 }
1072
1073
1074 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1075 // re-patch all oop-bearing instructions, just in case some oops moved
1076 RelocIterator iter(this, begin, end);
1077 while (iter.next()) {
1078 if (iter.type() == relocInfo::oop_type) {
1079 oop_Relocation* reloc = iter.oop_reloc();
1080 if (initialize_immediates && reloc->oop_is_immediate()) {
1081 oop* dest = reloc->oop_addr();
1082 initialize_immediate_oop(dest, (jobject) *dest);
1083 }
1084 // Refresh the oop-related bits of this instruction.
1085 reloc->fix_oop_relocation();
1086 } else if (iter.type() == relocInfo::metadata_type) {
1087 metadata_Relocation* reloc = iter.metadata_reloc();
1088 reloc->fix_metadata_relocation();
1089 }
1090 }
1091 }
1092
1093
1094 void nmethod::verify_oop_relocations() {
1095 // Ensure sure that the code matches the current oop values
1096 RelocIterator iter(this, NULL, NULL);
1097 while (iter.next()) {
1098 if (iter.type() == relocInfo::oop_type) {
1099 oop_Relocation* reloc = iter.oop_reloc();
1100 if (!reloc->oop_is_immediate()) {
1101 reloc->verify_oop_relocation();
1102 }
1103 }
1104 }
1105 }
1106
1107
1108 ScopeDesc* nmethod::scope_desc_at(address pc) {
1109 PcDesc* pd = pc_desc_at(pc);
1110 guarantee(pd != NULL, "scope must be present");
1111 return new ScopeDesc(this, pd->scope_decode_offset(),
1112 pd->obj_decode_offset(), pd->should_reexecute(),
1113 pd->return_oop());
1114 }
1115
1116
1117 void nmethod::clear_inline_caches() {
1118 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1119 if (is_zombie()) {
1120 return;
1121 }
1122
1123 RelocIterator iter(this);
1124 while (iter.next()) {
1125 iter.reloc()->clear_inline_cache();
1126 }
1127 }
1128
1129
1130 void nmethod::cleanup_inline_caches() {
1131
1132 assert_locked_or_safepoint(CompiledIC_lock);
1133
1134 // If the method is not entrant or zombie then a JMP is plastered over the
1135 // first few bytes. If an oop in the old code was there, that oop
1136 // should not get GC'd. Skip the first few bytes of oops on
1137 // not-entrant methods.
1138 address low_boundary = verified_entry_point();
1139 if (!is_in_use()) {
1140 low_boundary += NativeJump::instruction_size;
1141 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1142 // This means that the low_boundary is going to be a little too high.
1143 // This shouldn't matter, since oops of non-entrant methods are never used.
1144 // In fact, why are we bothering to look at oops in a non-entrant method??
1145 }
1146
1147 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1148 ResourceMark rm;
1149 RelocIterator iter(this, low_boundary);
1150 while(iter.next()) {
1151 switch(iter.type()) {
1152 case relocInfo::virtual_call_type:
1153 case relocInfo::opt_virtual_call_type: {
1154 CompiledIC *ic = CompiledIC_at(iter.reloc());
1155 // Ok, to lookup references to zombies here
1156 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1157 if( cb != NULL && cb->is_nmethod() ) {
1158 nmethod* nm = (nmethod*)cb;
1159 // Clean inline caches pointing to both zombie and not_entrant methods
1160 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1161 }
1162 break;
1163 }
1164 case relocInfo::static_call_type: {
1165 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1166 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1167 if( cb != NULL && cb->is_nmethod() ) {
1168 nmethod* nm = (nmethod*)cb;
1169 // Clean inline caches pointing to both zombie and not_entrant methods
1170 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1171 }
1172 break;
1173 }
1174 }
1175 }
1176 }
1177
1178 // This is a private interface with the sweeper.
1179 void nmethod::mark_as_seen_on_stack() {
1180 assert(is_alive(), "Must be an alive method");
1181 // Set the traversal mark to ensure that the sweeper does 2
1182 // cleaning passes before moving to zombie.
1183 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1184 }
1185
1186 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1187 // there are no activations on the stack, not in use by the VM,
1188 // and not in use by the ServiceThread)
1189 bool nmethod::can_not_entrant_be_converted() {
1190 assert(is_not_entrant(), "must be a non-entrant method");
1191
1192 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1193 // count can be greater than the stack traversal count before it hits the
1194 // nmethod for the second time.
1195 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1196 !is_locked_by_vm();
1197 }
1198
1199 void nmethod::inc_decompile_count() {
1200 if (!is_compiled_by_c2()) return;
1201 // Could be gated by ProfileTraps, but do not bother...
1202 Method* m = method();
1203 if (m == NULL) return;
1204 MethodData* mdo = m->method_data();
1205 if (mdo == NULL) return;
1206 // There is a benign race here. See comments in methodData.hpp.
1207 mdo->inc_decompile_count();
1208 }
1209
1210 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1211
1212 post_compiled_method_unload();
1213
1214 // Since this nmethod is being unloaded, make sure that dependencies
1215 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1216 // indicate that this work is being done during a GC.
1217 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1218 assert(is_alive != NULL, "Should be non-NULL");
1219 // A non-NULL is_alive closure indicates that this is being called during GC.
1220 flush_dependencies(is_alive);
1221
1222 // Break cycle between nmethod & method
1223 if (TraceClassUnloading && WizardMode) {
1224 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1225 " unloadable], Method*(" INTPTR_FORMAT
1226 "), cause(" INTPTR_FORMAT ")",
1227 this, (address)_method, (address)cause);
1228 if (!Universe::heap()->is_gc_active())
1229 cause->klass()->print();
1230 }
1231 // Unlink the osr method, so we do not look this up again
1232 if (is_osr_method()) {
1233 invalidate_osr_method();
1234 }
1235 // If _method is already NULL the Method* is about to be unloaded,
1236 // so we don't have to break the cycle. Note that it is possible to
1237 // have the Method* live here, in case we unload the nmethod because
1238 // it is pointing to some oop (other than the Method*) being unloaded.
1239 if (_method != NULL) {
1240 // OSR methods point to the Method*, but the Method* does not
1241 // point back!
1242 if (_method->code() == this) {
1243 _method->clear_code(); // Break a cycle
1244 }
1245 _method = NULL; // Clear the method of this dead nmethod
1246 }
1247 // Make the class unloaded - i.e., change state and notify sweeper
1248 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1249 if (is_in_use()) {
1250 // Transitioning directly from live to unloaded -- so
1251 // we need to force a cache clean-up; remember this
1252 // for later on.
1253 CodeCache::set_needs_cache_clean(true);
1254 }
1255 _state = unloaded;
1256
1257 // Log the unloading.
1258 log_state_change();
1259
1260 // The Method* is gone at this point
1261 assert(_method == NULL, "Tautology");
1262
1263 set_osr_link(NULL);
1264 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1265 }
1266
1267 void nmethod::invalidate_osr_method() {
1268 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1269 // Remove from list of active nmethods
1270 if (method() != NULL)
1271 method()->method_holder()->remove_osr_nmethod(this);
1272 // Set entry as invalid
1273 _entry_bci = InvalidOSREntryBci;
1274 }
1275
1276 void nmethod::log_state_change() const {
1277 if (LogCompilation) {
1278 if (xtty != NULL) {
1279 ttyLocker ttyl; // keep the following output all in one block
1280 if (_state == unloaded) {
1281 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1282 os::current_thread_id());
1283 } else {
1284 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1285 os::current_thread_id(),
1286 (_state == zombie ? " zombie='1'" : ""));
1287 }
1288 log_identity(xtty);
1289 xtty->stamp();
1290 xtty->end_elem();
1291 }
1292 }
1293 if (PrintCompilation && _state != unloaded) {
1294 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1295 }
1296 }
1297
1298 // Common functionality for both make_not_entrant and make_zombie
1299 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1300 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1301 assert(!is_zombie(), "should not already be a zombie");
1302
1303 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1304 nmethodLocker nml(this);
1305 methodHandle the_method(method());
1306 No_Safepoint_Verifier nsv;
1307
1308 // during patching, depending on the nmethod state we must notify the GC that
1309 // code has been unloaded, unregistering it. We cannot do this right while
1310 // holding the Patching_lock because we need to use the CodeCache_lock. This
1311 // would be prone to deadlocks.
1312 // This flag is used to remember whether we need to later lock and unregister.
1313 bool nmethod_needs_unregister = false;
1314
1315 {
1316 // invalidate osr nmethod before acquiring the patching lock since
1317 // they both acquire leaf locks and we don't want a deadlock.
1318 // This logic is equivalent to the logic below for patching the
1319 // verified entry point of regular methods.
1320 if (is_osr_method()) {
1321 // this effectively makes the osr nmethod not entrant
1322 invalidate_osr_method();
1323 }
1324
1325 // Enter critical section. Does not block for safepoint.
1326 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1327
1328 if (_state == state) {
1329 // another thread already performed this transition so nothing
1330 // to do, but return false to indicate this.
1331 return false;
1332 }
1333
1334 // The caller can be calling the method statically or through an inline
1335 // cache call.
1336 if (!is_osr_method() && !is_not_entrant()) {
1337 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1338 SharedRuntime::get_handle_wrong_method_stub());
1339 }
1340
1341 if (is_in_use()) {
1342 // It's a true state change, so mark the method as decompiled.
1343 // Do it only for transition from alive.
1344 inc_decompile_count();
1345 }
1346
1347 // If the state is becoming a zombie, signal to unregister the nmethod with
1348 // the heap.
1349 // This nmethod may have already been unloaded during a full GC.
1350 if ((state == zombie) && !is_unloaded()) {
1351 nmethod_needs_unregister = true;
1352 }
1353
1354 // Must happen before state change. Otherwise we have a race condition in
1355 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1356 // transition its state from 'not_entrant' to 'zombie' without having to wait
1357 // for stack scanning.
1358 if (state == not_entrant) {
1359 mark_as_seen_on_stack();
1360 OrderAccess::storestore();
1361 }
1362
1363 // Change state
1364 _state = state;
1365
1366 // Log the transition once
1367 log_state_change();
1368
1369 // Remove nmethod from method.
1370 // We need to check if both the _code and _from_compiled_code_entry_point
1371 // refer to this nmethod because there is a race in setting these two fields
1372 // in Method* as seen in bugid 4947125.
1373 // If the vep() points to the zombie nmethod, the memory for the nmethod
1374 // could be flushed and the compiler and vtable stubs could still call
1375 // through it.
1376 if (method() != NULL && (method()->code() == this ||
1377 method()->from_compiled_entry() == verified_entry_point())) {
1378 HandleMark hm;
1379 method()->clear_code();
1380 }
1381 } // leave critical region under Patching_lock
1382
1383 // When the nmethod becomes zombie it is no longer alive so the
1384 // dependencies must be flushed. nmethods in the not_entrant
1385 // state will be flushed later when the transition to zombie
1386 // happens or they get unloaded.
1387 if (state == zombie) {
1388 {
1389 // Flushing dependecies must be done before any possible
1390 // safepoint can sneak in, otherwise the oops used by the
1391 // dependency logic could have become stale.
1392 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1393 if (nmethod_needs_unregister) {
1394 Universe::heap()->unregister_nmethod(this);
1395 }
1396 flush_dependencies(NULL);
1397 }
1398
1399 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1400 // event and it hasn't already been reported for this nmethod then
1401 // report it now. The event may have been reported earilier if the GC
1402 // marked it for unloading). JvmtiDeferredEventQueue support means
1403 // we no longer go to a safepoint here.
1404 post_compiled_method_unload();
1405
1406 #ifdef ASSERT
1407 // It's no longer safe to access the oops section since zombie
1408 // nmethods aren't scanned for GC.
1409 _oops_are_stale = true;
1410 #endif
1411 // the Method may be reclaimed by class unloading now that the
1412 // nmethod is in zombie state
1413 set_method(NULL);
1414 } else {
1415 assert(state == not_entrant, "other cases may need to be handled differently");
1416 }
1417
1418 if (TraceCreateZombies) {
1419 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1420 }
1421
1422 return true;
1423 }
1424
1425 void nmethod::flush() {
1426 // Note that there are no valid oops in the nmethod anymore.
1427 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1428 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1429
1430 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1431 assert_locked_or_safepoint(CodeCache_lock);
1432
1433 // completely deallocate this method
1434 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1435 if (PrintMethodFlushing) {
1436 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1437 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
1438 }
1439
1440 // We need to deallocate any ExceptionCache data.
1441 // Note that we do not need to grab the nmethod lock for this, it
1442 // better be thread safe if we're disposing of it!
1443 ExceptionCache* ec = exception_cache();
1444 set_exception_cache(NULL);
1445 while(ec != NULL) {
1446 ExceptionCache* next = ec->next();
1447 delete ec;
1448 ec = next;
1449 }
1450
1451 if (on_scavenge_root_list()) {
1452 CodeCache::drop_scavenge_root_nmethod(this);
1453 }
1454
1455 #ifdef SHARK
1456 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1457 #endif // SHARK
1458
1459 ((CodeBlob*)(this))->flush();
1460
1461 CodeCache::free(this);
1462 }
1463
1464
1465 //
1466 // Notify all classes this nmethod is dependent on that it is no
1467 // longer dependent. This should only be called in two situations.
1468 // First, when a nmethod transitions to a zombie all dependents need
1469 // to be clear. Since zombification happens at a safepoint there's no
1470 // synchronization issues. The second place is a little more tricky.
1471 // During phase 1 of mark sweep class unloading may happen and as a
1472 // result some nmethods may get unloaded. In this case the flushing
1473 // of dependencies must happen during phase 1 since after GC any
1474 // dependencies in the unloaded nmethod won't be updated, so
1475 // traversing the dependency information in unsafe. In that case this
1476 // function is called with a non-NULL argument and this function only
1477 // notifies instanceKlasses that are reachable
1478
1479 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1480 assert_locked_or_safepoint(CodeCache_lock);
1481 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1482 "is_alive is non-NULL if and only if we are called during GC");
1483 if (!has_flushed_dependencies()) {
1484 set_has_flushed_dependencies();
1485 for (Dependencies::DepStream deps(this); deps.next(); ) {
1486 Klass* klass = deps.context_type();
1487 if (klass == NULL) continue; // ignore things like evol_method
1488
1489 // During GC the is_alive closure is non-NULL, and is used to
1490 // determine liveness of dependees that need to be updated.
1491 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1492 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1493 }
1494 }
1495 }
1496 }
1497
1498
1499 // If this oop is not live, the nmethod can be unloaded.
1500 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1501 assert(root != NULL, "just checking");
1502 oop obj = *root;
1503 if (obj == NULL || is_alive->do_object_b(obj)) {
1504 return false;
1505 }
1506
1507 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1508 // simply because one of its constant oops has gone dead.
1509 // No actual classes need to be unloaded in order for this to occur.
1510 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1511 make_unloaded(is_alive, obj);
1512 return true;
1513 }
1514
1515 // ------------------------------------------------------------------
1516 // post_compiled_method_load_event
1517 // new method for install_code() path
1518 // Transfer information from compilation to jvmti
1519 void nmethod::post_compiled_method_load_event() {
1520
1521 Method* moop = method();
1522 #ifndef USDT2
1523 HS_DTRACE_PROBE8(hotspot, compiled__method__load,
1524 moop->klass_name()->bytes(),
1525 moop->klass_name()->utf8_length(),
1526 moop->name()->bytes(),
1527 moop->name()->utf8_length(),
1528 moop->signature()->bytes(),
1529 moop->signature()->utf8_length(),
1530 insts_begin(), insts_size());
1531 #else /* USDT2 */
1532 HOTSPOT_COMPILED_METHOD_LOAD(
1533 (char *) moop->klass_name()->bytes(),
1534 moop->klass_name()->utf8_length(),
1535 (char *) moop->name()->bytes(),
1536 moop->name()->utf8_length(),
1537 (char *) moop->signature()->bytes(),
1538 moop->signature()->utf8_length(),
1539 insts_begin(), insts_size());
1540 #endif /* USDT2 */
1541
1542 if (JvmtiExport::should_post_compiled_method_load() ||
1543 JvmtiExport::should_post_compiled_method_unload()) {
1544 get_and_cache_jmethod_id();
1545 }
1546
1547 if (JvmtiExport::should_post_compiled_method_load()) {
1548 // Let the Service thread (which is a real Java thread) post the event
1549 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1550 JvmtiDeferredEventQueue::enqueue(
1551 JvmtiDeferredEvent::compiled_method_load_event(this));
1552 }
1553 }
1554
1555 jmethodID nmethod::get_and_cache_jmethod_id() {
1556 if (_jmethod_id == NULL) {
1557 // Cache the jmethod_id since it can no longer be looked up once the
1558 // method itself has been marked for unloading.
1559 _jmethod_id = method()->jmethod_id();
1560 }
1561 return _jmethod_id;
1562 }
1563
1564 void nmethod::post_compiled_method_unload() {
1565 if (unload_reported()) {
1566 // During unloading we transition to unloaded and then to zombie
1567 // and the unloading is reported during the first transition.
1568 return;
1569 }
1570
1571 assert(_method != NULL && !is_unloaded(), "just checking");
1572 DTRACE_METHOD_UNLOAD_PROBE(method());
1573
1574 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1575 // post the event. Sometime later this nmethod will be made a zombie
1576 // by the sweeper but the Method* will not be valid at that point.
1577 // If the _jmethod_id is null then no load event was ever requested
1578 // so don't bother posting the unload. The main reason for this is
1579 // that the jmethodID is a weak reference to the Method* so if
1580 // it's being unloaded there's no way to look it up since the weak
1581 // ref will have been cleared.
1582 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1583 assert(!unload_reported(), "already unloaded");
1584 JvmtiDeferredEvent event =
1585 JvmtiDeferredEvent::compiled_method_unload_event(this,
1586 _jmethod_id, insts_begin());
1587 if (SafepointSynchronize::is_at_safepoint()) {
1588 // Don't want to take the queueing lock. Add it as pending and
1589 // it will get enqueued later.
1590 JvmtiDeferredEventQueue::add_pending_event(event);
1591 } else {
1592 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1593 JvmtiDeferredEventQueue::enqueue(event);
1594 }
1595 }
1596
1597 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1598 // any time. As the nmethod is being unloaded now we mark it has
1599 // having the unload event reported - this will ensure that we don't
1600 // attempt to report the event in the unlikely scenario where the
1601 // event is enabled at the time the nmethod is made a zombie.
1602 set_unload_reported();
1603 }
1604
1605 // This is called at the end of the strong tracing/marking phase of a
1606 // GC to unload an nmethod if it contains otherwise unreachable
1607 // oops.
1608
1609 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1610 // Make sure the oop's ready to receive visitors
1611 assert(!is_zombie() && !is_unloaded(),
1612 "should not call follow on zombie or unloaded nmethod");
1613
1614 // If the method is not entrant then a JMP is plastered over the
1615 // first few bytes. If an oop in the old code was there, that oop
1616 // should not get GC'd. Skip the first few bytes of oops on
1617 // not-entrant methods.
1618 address low_boundary = verified_entry_point();
1619 if (is_not_entrant()) {
1620 low_boundary += NativeJump::instruction_size;
1621 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1622 // (See comment above.)
1623 }
1624
1625 // The RedefineClasses() API can cause the class unloading invariant
1626 // to no longer be true. See jvmtiExport.hpp for details.
1627 // Also, leave a debugging breadcrumb in local flag.
1628 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1629 if (a_class_was_redefined) {
1630 // This set of the unloading_occurred flag is done before the
1631 // call to post_compiled_method_unload() so that the unloading
1632 // of this nmethod is reported.
1633 unloading_occurred = true;
1634 }
1635
1636 // Exception cache
1637 ExceptionCache* ec = exception_cache();
1638 while (ec != NULL) {
1639 Klass* ex_klass = ec->exception_type();
1640 ExceptionCache* next_ec = ec->next();
1641 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
1642 remove_from_exception_cache(ec);
1643 }
1644 ec = next_ec;
1645 }
1646
1647 // If class unloading occurred we first iterate over all inline caches and
1648 // clear ICs where the cached oop is referring to an unloaded klass or method.
1649 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1650 // iteration below.
1651 if (unloading_occurred) {
1652 RelocIterator iter(this, low_boundary);
1653 while(iter.next()) {
1654 if (iter.type() == relocInfo::virtual_call_type) {
1655 CompiledIC *ic = CompiledIC_at(iter.reloc());
1656 if (ic->is_icholder_call()) {
1657 // The only exception is compiledICHolder oops which may
1658 // yet be marked below. (We check this further below).
1659 CompiledICHolder* cichk_oop = ic->cached_icholder();
1660 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1661 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1662 continue;
1663 }
1664 } else {
1665 Metadata* ic_oop = ic->cached_metadata();
1666 if (ic_oop != NULL) {
1667 if (ic_oop->is_klass()) {
1668 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1669 continue;
1670 }
1671 } else if (ic_oop->is_method()) {
1672 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1673 continue;
1674 }
1675 } else {
1676 ShouldNotReachHere();
1677 }
1678 }
1679 }
1680 ic->set_to_clean();
1681 }
1682 }
1683 }
1684
1685 // Compiled code
1686 {
1687 RelocIterator iter(this, low_boundary);
1688 while (iter.next()) {
1689 if (iter.type() == relocInfo::oop_type) {
1690 oop_Relocation* r = iter.oop_reloc();
1691 // In this loop, we must only traverse those oops directly embedded in
1692 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1693 assert(1 == (r->oop_is_immediate()) +
1694 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1695 "oop must be found in exactly one place");
1696 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1697 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1698 return;
1699 }
1700 }
1701 }
1702 }
1703 }
1704
1705
1706 // Scopes
1707 for (oop* p = oops_begin(); p < oops_end(); p++) {
1708 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1709 if (can_unload(is_alive, p, unloading_occurred)) {
1710 return;
1711 }
1712 }
1713
1714 // Ensure that all metadata is still alive
1715 verify_metadata_loaders(low_boundary, is_alive);
1716 }
1717
1718 #ifdef ASSERT
1719
1720 class CheckClass : AllStatic {
1721 static BoolObjectClosure* _is_alive;
1722
1723 // Check class_loader is alive for this bit of metadata.
1724 static void check_class(Metadata* md) {
1725 Klass* klass = NULL;
1726 if (md->is_klass()) {
1727 klass = ((Klass*)md);
1728 } else if (md->is_method()) {
1729 klass = ((Method*)md)->method_holder();
1730 } else if (md->is_methodData()) {
1731 klass = ((MethodData*)md)->method()->method_holder();
1732 } else {
1733 md->print();
1734 ShouldNotReachHere();
1735 }
1736 assert(klass->is_loader_alive(_is_alive), "must be alive");
1737 }
1738 public:
1739 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
1740 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
1741 _is_alive = is_alive;
1742 nm->metadata_do(check_class);
1743 }
1744 };
1745
1746 // This is called during a safepoint so can use static data
1747 BoolObjectClosure* CheckClass::_is_alive = NULL;
1748 #endif // ASSERT
1749
1750
1751 // Processing of oop references should have been sufficient to keep
1752 // all strong references alive. Any weak references should have been
1753 // cleared as well. Visit all the metadata and ensure that it's
1754 // really alive.
1755 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
1756 #ifdef ASSERT
1757 RelocIterator iter(this, low_boundary);
1758 while (iter.next()) {
1759 // static_stub_Relocations may have dangling references to
1760 // Method*s so trim them out here. Otherwise it looks like
1761 // compiled code is maintaining a link to dead metadata.
1762 address static_call_addr = NULL;
1763 if (iter.type() == relocInfo::opt_virtual_call_type) {
1764 CompiledIC* cic = CompiledIC_at(iter.reloc());
1765 if (!cic->is_call_to_interpreted()) {
1766 static_call_addr = iter.addr();
1767 }
1768 } else if (iter.type() == relocInfo::static_call_type) {
1769 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
1770 if (!csc->is_call_to_interpreted()) {
1771 static_call_addr = iter.addr();
1772 }
1773 }
1774 if (static_call_addr != NULL) {
1775 RelocIterator sciter(this, low_boundary);
1776 while (sciter.next()) {
1777 if (sciter.type() == relocInfo::static_stub_type &&
1778 sciter.static_stub_reloc()->static_call() == static_call_addr) {
1779 sciter.static_stub_reloc()->clear_inline_cache();
1780 }
1781 }
1782 }
1783 }
1784 // Check that the metadata embedded in the nmethod is alive
1785 CheckClass::do_check_class(is_alive, this);
1786 #endif
1787 }
1788
1789
1790 // Iterate over metadata calling this function. Used by RedefineClasses
1791 void nmethod::metadata_do(void f(Metadata*)) {
1792 address low_boundary = verified_entry_point();
1793 if (is_not_entrant()) {
1794 low_boundary += NativeJump::instruction_size;
1795 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1796 // (See comment above.)
1797 }
1798 {
1799 // Visit all immediate references that are embedded in the instruction stream.
1800 RelocIterator iter(this, low_boundary);
1801 while (iter.next()) {
1802 if (iter.type() == relocInfo::metadata_type ) {
1803 metadata_Relocation* r = iter.metadata_reloc();
1804 // In this lmetadata, we must only follow those metadatas directly embedded in
1805 // the code. Other metadatas (oop_index>0) are seen as part of
1806 // the metadata section below.
1807 assert(1 == (r->metadata_is_immediate()) +
1808 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1809 "metadata must be found in exactly one place");
1810 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1811 Metadata* md = r->metadata_value();
1812 f(md);
1813 }
1814 } else if (iter.type() == relocInfo::virtual_call_type) {
1815 // Check compiledIC holders associated with this nmethod
1816 CompiledIC *ic = CompiledIC_at(iter.reloc());
1817 if (ic->is_icholder_call()) {
1818 CompiledICHolder* cichk = ic->cached_icholder();
1819 f(cichk->holder_method());
1820 f(cichk->holder_klass());
1821 } else {
1822 Metadata* ic_oop = ic->cached_metadata();
1823 if (ic_oop != NULL) {
1824 f(ic_oop);
1825 }
1826 }
1827 }
1828 }
1829 }
1830
1831 // Visit the metadata section
1832 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1833 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
1834 Metadata* md = *p;
1835 f(md);
1836 }
1837
1838 // Call function Method*, not embedded in these other places.
1839 if (_method != NULL) f(_method);
1840 }
1841
1842 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1843 // make sure the oops ready to receive visitors
1844 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1845 assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1846
1847 // If the method is not entrant or zombie then a JMP is plastered over the
1848 // first few bytes. If an oop in the old code was there, that oop
1849 // should not get GC'd. Skip the first few bytes of oops on
1850 // not-entrant methods.
1851 address low_boundary = verified_entry_point();
1852 if (is_not_entrant()) {
1853 low_boundary += NativeJump::instruction_size;
1854 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1855 // (See comment above.)
1856 }
1857
1858 RelocIterator iter(this, low_boundary);
1859
1860 while (iter.next()) {
1861 if (iter.type() == relocInfo::oop_type ) {
1862 oop_Relocation* r = iter.oop_reloc();
1863 // In this loop, we must only follow those oops directly embedded in
1864 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1865 assert(1 == (r->oop_is_immediate()) +
1866 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1867 "oop must be found in exactly one place");
1868 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1869 f->do_oop(r->oop_addr());
1870 }
1871 }
1872 }
1873
1874 // Scopes
1875 // This includes oop constants not inlined in the code stream.
1876 for (oop* p = oops_begin(); p < oops_end(); p++) {
1877 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1878 f->do_oop(p);
1879 }
1880 }
1881
1882 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1883
1884 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1885
1886 // An nmethod is "marked" if its _mark_link is set non-null.
1887 // Even if it is the end of the linked list, it will have a non-null link value,
1888 // as long as it is on the list.
1889 // This code must be MP safe, because it is used from parallel GC passes.
1890 bool nmethod::test_set_oops_do_mark() {
1891 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1892 nmethod* observed_mark_link = _oops_do_mark_link;
1893 if (observed_mark_link == NULL) {
1894 // Claim this nmethod for this thread to mark.
1895 observed_mark_link = (nmethod*)
1896 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1897 if (observed_mark_link == NULL) {
1898
1899 // Atomically append this nmethod (now claimed) to the head of the list:
1900 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1901 for (;;) {
1902 nmethod* required_mark_nmethods = observed_mark_nmethods;
1903 _oops_do_mark_link = required_mark_nmethods;
1904 observed_mark_nmethods = (nmethod*)
1905 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1906 if (observed_mark_nmethods == required_mark_nmethods)
1907 break;
1908 }
1909 // Mark was clear when we first saw this guy.
1910 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
1911 return false;
1912 }
1913 }
1914 // On fall through, another racing thread marked this nmethod before we did.
1915 return true;
1916 }
1917
1918 void nmethod::oops_do_marking_prologue() {
1919 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
1920 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1921 // We use cmpxchg_ptr instead of regular assignment here because the user
1922 // may fork a bunch of threads, and we need them all to see the same state.
1923 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1924 guarantee(observed == NULL, "no races in this sequential code");
1925 }
1926
1927 void nmethod::oops_do_marking_epilogue() {
1928 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1929 nmethod* cur = _oops_do_mark_nmethods;
1930 while (cur != NMETHOD_SENTINEL) {
1931 assert(cur != NULL, "not NULL-terminated");
1932 nmethod* next = cur->_oops_do_mark_link;
1933 cur->_oops_do_mark_link = NULL;
1934 cur->fix_oop_relocations();
1935 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
1936 cur = next;
1937 }
1938 void* required = _oops_do_mark_nmethods;
1939 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1940 guarantee(observed == required, "no races in this sequential code");
1941 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
1942 }
1943
1944 class DetectScavengeRoot: public OopClosure {
1945 bool _detected_scavenge_root;
1946 public:
1947 DetectScavengeRoot() : _detected_scavenge_root(false)
1948 { NOT_PRODUCT(_print_nm = NULL); }
1949 bool detected_scavenge_root() { return _detected_scavenge_root; }
1950 virtual void do_oop(oop* p) {
1951 if ((*p) != NULL && (*p)->is_scavengable()) {
1952 NOT_PRODUCT(maybe_print(p));
1953 _detected_scavenge_root = true;
1954 }
1955 }
1956 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1957
1958 #ifndef PRODUCT
1959 nmethod* _print_nm;
1960 void maybe_print(oop* p) {
1961 if (_print_nm == NULL) return;
1962 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
1963 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
1964 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
1965 (void *)(*p), (intptr_t)p);
1966 (*p)->print();
1967 }
1968 #endif //PRODUCT
1969 };
1970
1971 bool nmethod::detect_scavenge_root_oops() {
1972 DetectScavengeRoot detect_scavenge_root;
1973 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
1974 oops_do(&detect_scavenge_root);
1975 return detect_scavenge_root.detected_scavenge_root();
1976 }
1977
1978 // Method that knows how to preserve outgoing arguments at call. This method must be
1979 // called with a frame corresponding to a Java invoke
1980 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1981 #ifndef SHARK
1982 if (!method()->is_native()) {
1983 SimpleScopeDesc ssd(this, fr.pc());
1984 Bytecode_invoke call(ssd.method(), ssd.bci());
1985 bool has_receiver = call.has_receiver();
1986 bool has_appendix = call.has_appendix();
1987 Symbol* signature = call.signature();
1988 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
1989 }
1990 #endif // !SHARK
1991 }
1992
1993
1994 oop nmethod::embeddedOop_at(u_char* p) {
1995 RelocIterator iter(this, p, p + 1);
1996 while (iter.next())
1997 if (iter.type() == relocInfo::oop_type) {
1998 return iter.oop_reloc()->oop_value();
1999 }
2000 return NULL;
2001 }
2002
2003
2004 inline bool includes(void* p, void* from, void* to) {
2005 return from <= p && p < to;
2006 }
2007
2008
2009 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2010 assert(count >= 2, "must be sentinel values, at least");
2011
2012 #ifdef ASSERT
2013 // must be sorted and unique; we do a binary search in find_pc_desc()
2014 int prev_offset = pcs[0].pc_offset();
2015 assert(prev_offset == PcDesc::lower_offset_limit,
2016 "must start with a sentinel");
2017 for (int i = 1; i < count; i++) {
2018 int this_offset = pcs[i].pc_offset();
2019 assert(this_offset > prev_offset, "offsets must be sorted");
2020 prev_offset = this_offset;
2021 }
2022 assert(prev_offset == PcDesc::upper_offset_limit,
2023 "must end with a sentinel");
2024 #endif //ASSERT
2025
2026 // Search for MethodHandle invokes and tag the nmethod.
2027 for (int i = 0; i < count; i++) {
2028 if (pcs[i].is_method_handle_invoke()) {
2029 set_has_method_handle_invokes(true);
2030 break;
2031 }
2032 }
2033 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2034
2035 int size = count * sizeof(PcDesc);
2036 assert(scopes_pcs_size() >= size, "oob");
2037 memcpy(scopes_pcs_begin(), pcs, size);
2038
2039 // Adjust the final sentinel downward.
2040 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2041 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2042 last_pc->set_pc_offset(content_size() + 1);
2043 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2044 // Fill any rounding gaps with copies of the last record.
2045 last_pc[1] = last_pc[0];
2046 }
2047 // The following assert could fail if sizeof(PcDesc) is not
2048 // an integral multiple of oopSize (the rounding term).
2049 // If it fails, change the logic to always allocate a multiple
2050 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2051 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2052 }
2053
2054 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2055 assert(scopes_data_size() >= size, "oob");
2056 memcpy(scopes_data_begin(), buffer, size);
2057 }
2058
2059
2060 #ifdef ASSERT
2061 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2062 PcDesc* lower = nm->scopes_pcs_begin();
2063 PcDesc* upper = nm->scopes_pcs_end();
2064 lower += 1; // exclude initial sentinel
2065 PcDesc* res = NULL;
2066 for (PcDesc* p = lower; p < upper; p++) {
2067 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2068 if (match_desc(p, pc_offset, approximate)) {
2069 if (res == NULL)
2070 res = p;
2071 else
2072 res = (PcDesc*) badAddress;
2073 }
2074 }
2075 return res;
2076 }
2077 #endif
2078
2079
2080 // Finds a PcDesc with real-pc equal to "pc"
2081 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2082 address base_address = code_begin();
2083 if ((pc < base_address) ||
2084 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2085 return NULL; // PC is wildly out of range
2086 }
2087 int pc_offset = (int) (pc - base_address);
2088
2089 // Check the PcDesc cache if it contains the desired PcDesc
2090 // (This as an almost 100% hit rate.)
2091 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2092 if (res != NULL) {
2093 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2094 return res;
2095 }
2096
2097 // Fallback algorithm: quasi-linear search for the PcDesc
2098 // Find the last pc_offset less than the given offset.
2099 // The successor must be the required match, if there is a match at all.
2100 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2101 PcDesc* lower = scopes_pcs_begin();
2102 PcDesc* upper = scopes_pcs_end();
2103 upper -= 1; // exclude final sentinel
2104 if (lower >= upper) return NULL; // native method; no PcDescs at all
2105
2106 #define assert_LU_OK \
2107 /* invariant on lower..upper during the following search: */ \
2108 assert(lower->pc_offset() < pc_offset, "sanity"); \
2109 assert(upper->pc_offset() >= pc_offset, "sanity")
2110 assert_LU_OK;
2111
2112 // Use the last successful return as a split point.
2113 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2114 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2115 if (mid->pc_offset() < pc_offset) {
2116 lower = mid;
2117 } else {
2118 upper = mid;
2119 }
2120
2121 // Take giant steps at first (4096, then 256, then 16, then 1)
2122 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2123 const int RADIX = (1 << LOG2_RADIX);
2124 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2125 while ((mid = lower + step) < upper) {
2126 assert_LU_OK;
2127 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2128 if (mid->pc_offset() < pc_offset) {
2129 lower = mid;
2130 } else {
2131 upper = mid;
2132 break;
2133 }
2134 }
2135 assert_LU_OK;
2136 }
2137
2138 // Sneak up on the value with a linear search of length ~16.
2139 while (true) {
2140 assert_LU_OK;
2141 mid = lower + 1;
2142 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2143 if (mid->pc_offset() < pc_offset) {
2144 lower = mid;
2145 } else {
2146 upper = mid;
2147 break;
2148 }
2149 }
2150 #undef assert_LU_OK
2151
2152 if (match_desc(upper, pc_offset, approximate)) {
2153 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2154 _pc_desc_cache.add_pc_desc(upper);
2155 return upper;
2156 } else {
2157 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2158 return NULL;
2159 }
2160 }
2161
2162
2163 bool nmethod::check_all_dependencies() {
2164 bool found_check = false;
2165 // wholesale check of all dependencies
2166 for (Dependencies::DepStream deps(this); deps.next(); ) {
2167 if (deps.check_dependency() != NULL) {
2168 found_check = true;
2169 NOT_DEBUG(break);
2170 }
2171 }
2172 return found_check; // tell caller if we found anything
2173 }
2174
2175 bool nmethod::check_dependency_on(DepChange& changes) {
2176 // What has happened:
2177 // 1) a new class dependee has been added
2178 // 2) dependee and all its super classes have been marked
2179 bool found_check = false; // set true if we are upset
2180 for (Dependencies::DepStream deps(this); deps.next(); ) {
2181 // Evaluate only relevant dependencies.
2182 if (deps.spot_check_dependency_at(changes) != NULL) {
2183 found_check = true;
2184 NOT_DEBUG(break);
2185 }
2186 }
2187 return found_check;
2188 }
2189
2190 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2191 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2192 Array<Method*>* dependee_methods = dependee_ik->methods();
2193 for (Dependencies::DepStream deps(this); deps.next(); ) {
2194 if (deps.type() == Dependencies::evol_method) {
2195 Method* method = deps.method_argument(0);
2196 for (int j = 0; j < dependee_methods->length(); j++) {
2197 if (dependee_methods->at(j) == method) {
2198 // RC_TRACE macro has an embedded ResourceMark
2199 RC_TRACE(0x01000000,
2200 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2201 _method->method_holder()->external_name(),
2202 _method->name()->as_C_string(),
2203 _method->signature()->as_C_string(), compile_id(),
2204 method->method_holder()->external_name(),
2205 method->name()->as_C_string(),
2206 method->signature()->as_C_string()));
2207 if (TraceDependencies || LogCompilation)
2208 deps.log_dependency(dependee);
2209 return true;
2210 }
2211 }
2212 }
2213 }
2214 return false;
2215 }
2216
2217 // Called from mark_for_deoptimization, when dependee is invalidated.
2218 bool nmethod::is_dependent_on_method(Method* dependee) {
2219 for (Dependencies::DepStream deps(this); deps.next(); ) {
2220 if (deps.type() != Dependencies::evol_method)
2221 continue;
2222 Method* method = deps.method_argument(0);
2223 if (method == dependee) return true;
2224 }
2225 return false;
2226 }
2227
2228
2229 bool nmethod::is_patchable_at(address instr_addr) {
2230 assert(insts_contains(instr_addr), "wrong nmethod used");
2231 if (is_zombie()) {
2232 // a zombie may never be patched
2233 return false;
2234 }
2235 return true;
2236 }
2237
2238
2239 address nmethod::continuation_for_implicit_exception(address pc) {
2240 // Exception happened outside inline-cache check code => we are inside
2241 // an active nmethod => use cpc to determine a return address
2242 int exception_offset = pc - code_begin();
2243 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2244 #ifdef ASSERT
2245 if (cont_offset == 0) {
2246 Thread* thread = ThreadLocalStorage::get_thread_slow();
2247 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2248 HandleMark hm(thread);
2249 ResourceMark rm(thread);
2250 CodeBlob* cb = CodeCache::find_blob(pc);
2251 assert(cb != NULL && cb == this, "");
2252 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2253 print();
2254 method()->print_codes();
2255 print_code();
2256 print_pcs();
2257 }
2258 #endif
2259 if (cont_offset == 0) {
2260 // Let the normal error handling report the exception
2261 return NULL;
2262 }
2263 return code_begin() + cont_offset;
2264 }
2265
2266
2267
2268 void nmethod_init() {
2269 // make sure you didn't forget to adjust the filler fields
2270 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2271 }
2272
2273
2274 //-------------------------------------------------------------------------------------------
2275
2276
2277 // QQQ might we make this work from a frame??
2278 nmethodLocker::nmethodLocker(address pc) {
2279 CodeBlob* cb = CodeCache::find_blob(pc);
2280 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2281 _nm = (nmethod*)cb;
2282 lock_nmethod(_nm);
2283 }
2284
2285 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2286 // should pass zombie_ok == true.
2287 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2288 if (nm == NULL) return;
2289 Atomic::inc(&nm->_lock_count);
2290 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2291 }
2292
2293 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2294 if (nm == NULL) return;
2295 Atomic::dec(&nm->_lock_count);
2296 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2297 }
2298
2299
2300 // -----------------------------------------------------------------------------
2301 // nmethod::get_deopt_original_pc
2302 //
2303 // Return the original PC for the given PC if:
2304 // (a) the given PC belongs to a nmethod and
2305 // (b) it is a deopt PC
2306 address nmethod::get_deopt_original_pc(const frame* fr) {
2307 if (fr->cb() == NULL) return NULL;
2308
2309 nmethod* nm = fr->cb()->as_nmethod_or_null();
2310 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2311 return nm->get_original_pc(fr);
2312
2313 return NULL;
2314 }
2315
2316
2317 // -----------------------------------------------------------------------------
2318 // MethodHandle
2319
2320 bool nmethod::is_method_handle_return(address return_pc) {
2321 if (!has_method_handle_invokes()) return false;
2322 PcDesc* pd = pc_desc_at(return_pc);
2323 if (pd == NULL)
2324 return false;
2325 return pd->is_method_handle_invoke();
2326 }
2327
2328
2329 // -----------------------------------------------------------------------------
2330 // Verification
2331
2332 class VerifyOopsClosure: public OopClosure {
2333 nmethod* _nm;
2334 bool _ok;
2335 public:
2336 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2337 bool ok() { return _ok; }
2338 virtual void do_oop(oop* p) {
2339 if ((*p) == NULL || (*p)->is_oop()) return;
2340 if (_ok) {
2341 _nm->print_nmethod(true);
2342 _ok = false;
2343 }
2344 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2345 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2346 }
2347 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2348 };
2349
2350 void nmethod::verify() {
2351
2352 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2353 // seems odd.
2354
2355 if( is_zombie() || is_not_entrant() )
2356 return;
2357
2358 // Make sure all the entry points are correctly aligned for patching.
2359 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2360
2361 // assert(method()->is_oop(), "must be valid");
2362
2363 ResourceMark rm;
2364
2365 if (!CodeCache::contains(this)) {
2366 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2367 }
2368
2369 if(is_native_method() )
2370 return;
2371
2372 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2373 if (nm != this) {
2374 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2375 this));
2376 }
2377
2378 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2379 if (! p->verify(this)) {
2380 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2381 }
2382 }
2383
2384 VerifyOopsClosure voc(this);
2385 oops_do(&voc);
2386 assert(voc.ok(), "embedded oops must be OK");
2387 verify_scavenge_root_oops();
2388
2389 verify_scopes();
2390 }
2391
2392
2393 void nmethod::verify_interrupt_point(address call_site) {
2394 // This code does not work in release mode since
2395 // owns_lock only is available in debug mode.
2396 CompiledIC* ic = NULL;
2397 Thread *cur = Thread::current();
2398 if (CompiledIC_lock->owner() == cur ||
2399 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2400 SafepointSynchronize::is_at_safepoint())) {
2401 ic = CompiledIC_at(this, call_site);
2402 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2403 } else {
2404 MutexLocker ml_verify (CompiledIC_lock);
2405 ic = CompiledIC_at(this, call_site);
2406 }
2407 PcDesc* pd = pc_desc_at(ic->end_of_call());
2408 assert(pd != NULL, "PcDesc must exist");
2409 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2410 pd->obj_decode_offset(), pd->should_reexecute(),
2411 pd->return_oop());
2412 !sd->is_top(); sd = sd->sender()) {
2413 sd->verify();
2414 }
2415 }
2416
2417 void nmethod::verify_scopes() {
2418 if( !method() ) return; // Runtime stubs have no scope
2419 if (method()->is_native()) return; // Ignore stub methods.
2420 // iterate through all interrupt point
2421 // and verify the debug information is valid.
2422 RelocIterator iter((nmethod*)this);
2423 while (iter.next()) {
2424 address stub = NULL;
2425 switch (iter.type()) {
2426 case relocInfo::virtual_call_type:
2427 verify_interrupt_point(iter.addr());
2428 break;
2429 case relocInfo::opt_virtual_call_type:
2430 stub = iter.opt_virtual_call_reloc()->static_stub();
2431 verify_interrupt_point(iter.addr());
2432 break;
2433 case relocInfo::static_call_type:
2434 stub = iter.static_call_reloc()->static_stub();
2435 //verify_interrupt_point(iter.addr());
2436 break;
2437 case relocInfo::runtime_call_type:
2438 address destination = iter.reloc()->value();
2439 // Right now there is no way to find out which entries support
2440 // an interrupt point. It would be nice if we had this
2441 // information in a table.
2442 break;
2443 }
2444 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2445 }
2446 }
2447
2448
2449 // -----------------------------------------------------------------------------
2450 // Non-product code
2451 #ifndef PRODUCT
2452
2453 class DebugScavengeRoot: public OopClosure {
2454 nmethod* _nm;
2455 bool _ok;
2456 public:
2457 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2458 bool ok() { return _ok; }
2459 virtual void do_oop(oop* p) {
2460 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2461 if (_ok) {
2462 _nm->print_nmethod(true);
2463 _ok = false;
2464 }
2465 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2466 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2467 (*p)->print();
2468 }
2469 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2470 };
2471
2472 void nmethod::verify_scavenge_root_oops() {
2473 if (!on_scavenge_root_list()) {
2474 // Actually look inside, to verify the claim that it's clean.
2475 DebugScavengeRoot debug_scavenge_root(this);
2476 oops_do(&debug_scavenge_root);
2477 if (!debug_scavenge_root.ok())
2478 fatal("found an unadvertised bad scavengable oop in the code cache");
2479 }
2480 assert(scavenge_root_not_marked(), "");
2481 }
2482
2483 #endif // PRODUCT
2484
2485 // Printing operations
2486
2487 void nmethod::print() const {
2488 ResourceMark rm;
2489 ttyLocker ttyl; // keep the following output all in one block
2490
2491 tty->print("Compiled method ");
2492
2493 if (is_compiled_by_c1()) {
2494 tty->print("(c1) ");
2495 } else if (is_compiled_by_c2()) {
2496 tty->print("(c2) ");
2497 } else if (is_compiled_by_shark()) {
2498 tty->print("(shark) ");
2499 } else {
2500 tty->print("(nm) ");
2501 }
2502
2503 print_on(tty, NULL);
2504
2505 if (WizardMode) {
2506 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2507 tty->print(" for method " INTPTR_FORMAT , (address)method());
2508 tty->print(" { ");
2509 if (is_in_use()) tty->print("in_use ");
2510 if (is_not_entrant()) tty->print("not_entrant ");
2511 if (is_zombie()) tty->print("zombie ");
2512 if (is_unloaded()) tty->print("unloaded ");
2513 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2514 tty->print_cr("}:");
2515 }
2516 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2517 (address)this,
2518 (address)this + size(),
2519 size());
2520 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2521 relocation_begin(),
2522 relocation_end(),
2523 relocation_size());
2524 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2525 consts_begin(),
2526 consts_end(),
2527 consts_size());
2528 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2529 insts_begin(),
2530 insts_end(),
2531 insts_size());
2532 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2533 stub_begin(),
2534 stub_end(),
2535 stub_size());
2536 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2537 oops_begin(),
2538 oops_end(),
2539 oops_size());
2540 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2541 metadata_begin(),
2542 metadata_end(),
2543 metadata_size());
2544 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2545 scopes_data_begin(),
2546 scopes_data_end(),
2547 scopes_data_size());
2548 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2549 scopes_pcs_begin(),
2550 scopes_pcs_end(),
2551 scopes_pcs_size());
2552 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2553 dependencies_begin(),
2554 dependencies_end(),
2555 dependencies_size());
2556 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2557 handler_table_begin(),
2558 handler_table_end(),
2559 handler_table_size());
2560 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2561 nul_chk_table_begin(),
2562 nul_chk_table_end(),
2563 nul_chk_table_size());
2564 }
2565
2566 void nmethod::print_code() {
2567 HandleMark hm;
2568 ResourceMark m;
2569 Disassembler::decode(this);
2570 }
2571
2572
2573 #ifndef PRODUCT
2574
2575 void nmethod::print_scopes() {
2576 // Find the first pc desc for all scopes in the code and print it.
2577 ResourceMark rm;
2578 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2579 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2580 continue;
2581
2582 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2583 sd->print_on(tty, p);
2584 }
2585 }
2586
2587 void nmethod::print_dependencies() {
2588 ResourceMark rm;
2589 ttyLocker ttyl; // keep the following output all in one block
2590 tty->print_cr("Dependencies:");
2591 for (Dependencies::DepStream deps(this); deps.next(); ) {
2592 deps.print_dependency();
2593 Klass* ctxk = deps.context_type();
2594 if (ctxk != NULL) {
2595 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2596 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2597 }
2598 }
2599 deps.log_dependency(); // put it into the xml log also
2600 }
2601 }
2602
2603
2604 void nmethod::print_relocations() {
2605 ResourceMark m; // in case methods get printed via the debugger
2606 tty->print_cr("relocations:");
2607 RelocIterator iter(this);
2608 iter.print();
2609 if (UseRelocIndex) {
2610 jint* index_end = (jint*)relocation_end() - 1;
2611 jint index_size = *index_end;
2612 jint* index_start = (jint*)( (address)index_end - index_size );
2613 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2614 if (index_size > 0) {
2615 jint* ip;
2616 for (ip = index_start; ip+2 <= index_end; ip += 2)
2617 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2618 ip[0],
2619 ip[1],
2620 header_end()+ip[0],
2621 relocation_begin()-1+ip[1]);
2622 for (; ip < index_end; ip++)
2623 tty->print_cr(" (%d ?)", ip[0]);
2624 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip);
2625 ip++;
2626 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2627 }
2628 }
2629 }
2630
2631
2632 void nmethod::print_pcs() {
2633 ResourceMark m; // in case methods get printed via debugger
2634 tty->print_cr("pc-bytecode offsets:");
2635 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2636 p->print(this);
2637 }
2638 }
2639
2640 #endif // PRODUCT
2641
2642 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2643 RelocIterator iter(this, begin, end);
2644 bool have_one = false;
2645 while (iter.next()) {
2646 have_one = true;
2647 switch (iter.type()) {
2648 case relocInfo::none: return "no_reloc";
2649 case relocInfo::oop_type: {
2650 stringStream st;
2651 oop_Relocation* r = iter.oop_reloc();
2652 oop obj = r->oop_value();
2653 st.print("oop(");
2654 if (obj == NULL) st.print("NULL");
2655 else obj->print_value_on(&st);
2656 st.print(")");
2657 return st.as_string();
2658 }
2659 case relocInfo::metadata_type: {
2660 stringStream st;
2661 metadata_Relocation* r = iter.metadata_reloc();
2662 Metadata* obj = r->metadata_value();
2663 st.print("metadata(");
2664 if (obj == NULL) st.print("NULL");
2665 else obj->print_value_on(&st);
2666 st.print(")");
2667 return st.as_string();
2668 }
2669 case relocInfo::virtual_call_type: return "virtual_call";
2670 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2671 case relocInfo::static_call_type: return "static_call";
2672 case relocInfo::static_stub_type: return "static_stub";
2673 case relocInfo::runtime_call_type: return "runtime_call";
2674 case relocInfo::external_word_type: return "external_word";
2675 case relocInfo::internal_word_type: return "internal_word";
2676 case relocInfo::section_word_type: return "section_word";
2677 case relocInfo::poll_type: return "poll";
2678 case relocInfo::poll_return_type: return "poll_return";
2679 case relocInfo::type_mask: return "type_bit_mask";
2680 }
2681 }
2682 return have_one ? "other" : NULL;
2683 }
2684
2685 // Return a the last scope in (begin..end]
2686 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2687 PcDesc* p = pc_desc_near(begin+1);
2688 if (p != NULL && p->real_pc(this) <= end) {
2689 return new ScopeDesc(this, p->scope_decode_offset(),
2690 p->obj_decode_offset(), p->should_reexecute(),
2691 p->return_oop());
2692 }
2693 return NULL;
2694 }
2695
2696 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2697 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2698 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2699 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2700 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2701 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2702
2703 if (has_method_handle_invokes())
2704 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
2705
2706 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
2707
2708 if (block_begin == entry_point()) {
2709 methodHandle m = method();
2710 if (m.not_null()) {
2711 stream->print(" # ");
2712 m->print_value_on(stream);
2713 stream->cr();
2714 }
2715 if (m.not_null() && !is_osr_method()) {
2716 ResourceMark rm;
2717 int sizeargs = m->size_of_parameters();
2718 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2719 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2720 {
2721 int sig_index = 0;
2722 if (!m->is_static())
2723 sig_bt[sig_index++] = T_OBJECT; // 'this'
2724 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2725 BasicType t = ss.type();
2726 sig_bt[sig_index++] = t;
2727 if (type2size[t] == 2) {
2728 sig_bt[sig_index++] = T_VOID;
2729 } else {
2730 assert(type2size[t] == 1, "size is 1 or 2");
2731 }
2732 }
2733 assert(sig_index == sizeargs, "");
2734 }
2735 const char* spname = "sp"; // make arch-specific?
2736 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2737 int stack_slot_offset = this->frame_size() * wordSize;
2738 int tab1 = 14, tab2 = 24;
2739 int sig_index = 0;
2740 int arg_index = (m->is_static() ? 0 : -1);
2741 bool did_old_sp = false;
2742 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2743 bool at_this = (arg_index == -1);
2744 bool at_old_sp = false;
2745 BasicType t = (at_this ? T_OBJECT : ss.type());
2746 assert(t == sig_bt[sig_index], "sigs in sync");
2747 if (at_this)
2748 stream->print(" # this: ");
2749 else
2750 stream->print(" # parm%d: ", arg_index);
2751 stream->move_to(tab1);
2752 VMReg fst = regs[sig_index].first();
2753 VMReg snd = regs[sig_index].second();
2754 if (fst->is_reg()) {
2755 stream->print("%s", fst->name());
2756 if (snd->is_valid()) {
2757 stream->print(":%s", snd->name());
2758 }
2759 } else if (fst->is_stack()) {
2760 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2761 if (offset == stack_slot_offset) at_old_sp = true;
2762 stream->print("[%s+0x%x]", spname, offset);
2763 } else {
2764 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2765 }
2766 stream->print(" ");
2767 stream->move_to(tab2);
2768 stream->print("= ");
2769 if (at_this) {
2770 m->method_holder()->print_value_on(stream);
2771 } else {
2772 bool did_name = false;
2773 if (!at_this && ss.is_object()) {
2774 Symbol* name = ss.as_symbol_or_null();
2775 if (name != NULL) {
2776 name->print_value_on(stream);
2777 did_name = true;
2778 }
2779 }
2780 if (!did_name)
2781 stream->print("%s", type2name(t));
2782 }
2783 if (at_old_sp) {
2784 stream->print(" (%s of caller)", spname);
2785 did_old_sp = true;
2786 }
2787 stream->cr();
2788 sig_index += type2size[t];
2789 arg_index += 1;
2790 if (!at_this) ss.next();
2791 }
2792 if (!did_old_sp) {
2793 stream->print(" # ");
2794 stream->move_to(tab1);
2795 stream->print("[%s+0x%x]", spname, stack_slot_offset);
2796 stream->print(" (%s of caller)", spname);
2797 stream->cr();
2798 }
2799 }
2800 }
2801 }
2802
2803 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2804 // First, find an oopmap in (begin, end].
2805 // We use the odd half-closed interval so that oop maps and scope descs
2806 // which are tied to the byte after a call are printed with the call itself.
2807 address base = code_begin();
2808 OopMapSet* oms = oop_maps();
2809 if (oms != NULL) {
2810 for (int i = 0, imax = oms->size(); i < imax; i++) {
2811 OopMap* om = oms->at(i);
2812 address pc = base + om->offset();
2813 if (pc > begin) {
2814 if (pc <= end) {
2815 st->move_to(column);
2816 st->print("; ");
2817 om->print_on(st);
2818 }
2819 break;
2820 }
2821 }
2822 }
2823
2824 // Print any debug info present at this pc.
2825 ScopeDesc* sd = scope_desc_in(begin, end);
2826 if (sd != NULL) {
2827 st->move_to(column);
2828 if (sd->bci() == SynchronizationEntryBCI) {
2829 st->print(";*synchronization entry");
2830 } else {
2831 if (sd->method() == NULL) {
2832 st->print("method is NULL");
2833 } else if (sd->method()->is_native()) {
2834 st->print("method is native");
2835 } else {
2836 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2837 st->print(";*%s", Bytecodes::name(bc));
2838 switch (bc) {
2839 case Bytecodes::_invokevirtual:
2840 case Bytecodes::_invokespecial:
2841 case Bytecodes::_invokestatic:
2842 case Bytecodes::_invokeinterface:
2843 {
2844 Bytecode_invoke invoke(sd->method(), sd->bci());
2845 st->print(" ");
2846 if (invoke.name() != NULL)
2847 invoke.name()->print_symbol_on(st);
2848 else
2849 st->print("<UNKNOWN>");
2850 break;
2851 }
2852 case Bytecodes::_getfield:
2853 case Bytecodes::_putfield:
2854 case Bytecodes::_getstatic:
2855 case Bytecodes::_putstatic:
2856 {
2857 Bytecode_field field(sd->method(), sd->bci());
2858 st->print(" ");
2859 if (field.name() != NULL)
2860 field.name()->print_symbol_on(st);
2861 else
2862 st->print("<UNKNOWN>");
2863 }
2864 }
2865 }
2866 }
2867
2868 // Print all scopes
2869 for (;sd != NULL; sd = sd->sender()) {
2870 st->move_to(column);
2871 st->print("; -");
2872 if (sd->method() == NULL) {
2873 st->print("method is NULL");
2874 } else {
2875 sd->method()->print_short_name(st);
2876 }
2877 int lineno = sd->method()->line_number_from_bci(sd->bci());
2878 if (lineno != -1) {
2879 st->print("@%d (line %d)", sd->bci(), lineno);
2880 } else {
2881 st->print("@%d", sd->bci());
2882 }
2883 st->cr();
2884 }
2885 }
2886
2887 // Print relocation information
2888 const char* str = reloc_string_for(begin, end);
2889 if (str != NULL) {
2890 if (sd != NULL) st->cr();
2891 st->move_to(column);
2892 st->print("; {%s}", str);
2893 }
2894 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2895 if (cont_offset != 0) {
2896 st->move_to(column);
2897 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
2898 }
2899
2900 }
2901
2902 #ifndef PRODUCT
2903
2904 void nmethod::print_value_on(outputStream* st) const {
2905 st->print("nmethod");
2906 print_on(st, NULL);
2907 }
2908
2909 void nmethod::print_calls(outputStream* st) {
2910 RelocIterator iter(this);
2911 while (iter.next()) {
2912 switch (iter.type()) {
2913 case relocInfo::virtual_call_type:
2914 case relocInfo::opt_virtual_call_type: {
2915 VerifyMutexLocker mc(CompiledIC_lock);
2916 CompiledIC_at(iter.reloc())->print();
2917 break;
2918 }
2919 case relocInfo::static_call_type:
2920 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2921 compiledStaticCall_at(iter.reloc())->print();
2922 break;
2923 }
2924 }
2925 }
2926
2927 void nmethod::print_handler_table() {
2928 ExceptionHandlerTable(this).print();
2929 }
2930
2931 void nmethod::print_nul_chk_table() {
2932 ImplicitExceptionTable(this).print(code_begin());
2933 }
2934
2935 void nmethod::print_statistics() {
2936 ttyLocker ttyl;
2937 if (xtty != NULL) xtty->head("statistics type='nmethod'");
2938 nmethod_stats.print_native_nmethod_stats();
2939 nmethod_stats.print_nmethod_stats();
2940 DebugInformationRecorder::print_statistics();
2941 nmethod_stats.print_pc_stats();
2942 Dependencies::print_statistics();
2943 if (xtty != NULL) xtty->tail("statistics");
2944 }
2945
2946 #endif // PRODUCT