1 /*
2 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "code/codeCache.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/dependencies.hpp"
29 #include "code/nmethod.hpp"
30 #include "code/scopeDesc.hpp"
31 #include "compiler/abstractCompiler.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/compileLog.hpp"
34 #include "compiler/compilerOracle.hpp"
35 #include "compiler/disassembler.hpp"
36 #include "interpreter/bytecode.hpp"
37 #include "oops/methodData.hpp"
38 #include "prims/jvmtiRedefineClassesTrace.hpp"
39 #include "prims/jvmtiImpl.hpp"
40 #include "runtime/sharedRuntime.hpp"
41 #include "runtime/sweeper.hpp"
42 #include "utilities/dtrace.hpp"
43 #include "utilities/events.hpp"
44 #include "utilities/xmlstream.hpp"
45 #ifdef SHARK
46 #include "shark/sharkCompiler.hpp"
47 #endif
48
49 #ifdef DTRACE_ENABLED
50
51 // Only bother with this argument setup if dtrace is available
52
53 #ifndef USDT2
54 HS_DTRACE_PROBE_DECL8(hotspot, compiled__method__load,
55 const char*, int, const char*, int, const char*, int, void*, size_t);
56
57 HS_DTRACE_PROBE_DECL6(hotspot, compiled__method__unload,
58 char*, int, char*, int, char*, int);
59
60 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
61 { \
62 Method* m = (method); \
63 if (m != NULL) { \
64 Symbol* klass_name = m->klass_name(); \
65 Symbol* name = m->name(); \
66 Symbol* signature = m->signature(); \
67 HS_DTRACE_PROBE6(hotspot, compiled__method__unload, \
68 klass_name->bytes(), klass_name->utf8_length(), \
69 name->bytes(), name->utf8_length(), \
70 signature->bytes(), signature->utf8_length()); \
71 } \
72 }
73 #else /* USDT2 */
74 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
75 { \
76 Method* m = (method); \
77 if (m != NULL) { \
78 Symbol* klass_name = m->klass_name(); \
79 Symbol* name = m->name(); \
80 Symbol* signature = m->signature(); \
81 HOTSPOT_COMPILED_METHOD_UNLOAD( \
82 (char *) klass_name->bytes(), klass_name->utf8_length(), \
83 (char *) name->bytes(), name->utf8_length(), \
84 (char *) signature->bytes(), signature->utf8_length()); \
85 } \
86 }
87 #endif /* USDT2 */
88
89 #else // ndef DTRACE_ENABLED
90
91 #define DTRACE_METHOD_UNLOAD_PROBE(method)
92
93 #endif
94
95 bool nmethod::is_compiled_by_c1() const {
96 if (compiler() == NULL) {
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 _speculatively_disconnected = 0;
466 _has_unsafe_access = 0;
467 _has_method_handle_invokes = 0;
468 _lazy_critical_native = 0;
469 _has_wide_vectors = 0;
470 _marked_for_deoptimization = 0;
471 _lock_count = 0;
472 _stack_traversal_mark = 0;
473 _unload_reported = false; // jvmti state
474
475 #ifdef ASSERT
476 _oops_are_stale = false;
477 #endif
478
479 _oops_do_mark_link = NULL;
480 _jmethod_id = NULL;
481 _osr_link = NULL;
482 _scavenge_root_link = NULL;
483 _scavenge_root_state = 0;
484 _saved_nmethod_link = NULL;
485 _compiler = NULL;
486
487 #ifdef HAVE_DTRACE_H
488 _trap_offset = 0;
489 #endif // def HAVE_DTRACE_H
490 }
491
492 nmethod* nmethod::new_native_nmethod(methodHandle method,
493 int compile_id,
494 CodeBuffer *code_buffer,
495 int vep_offset,
496 int frame_complete,
497 int frame_size,
498 ByteSize basic_lock_owner_sp_offset,
499 ByteSize basic_lock_sp_offset,
500 OopMapSet* oop_maps) {
501 code_buffer->finalize_oop_references(method);
502 // create nmethod
503 nmethod* nm = NULL;
504 {
505 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
506 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
507 CodeOffsets offsets;
508 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
509 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
510 nm = new (native_nmethod_size) nmethod(method(), native_nmethod_size,
511 compile_id, &offsets,
512 code_buffer, frame_size,
513 basic_lock_owner_sp_offset,
514 basic_lock_sp_offset, oop_maps);
515 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm));
516 if (PrintAssembly && nm != NULL) {
517 Disassembler::decode(nm);
518 }
519 }
520 // verify nmethod
521 debug_only(if (nm) nm->verify();) // might block
522
523 if (nm != NULL) {
524 nm->log_new_nmethod();
525 }
526
527 return nm;
528 }
529
530 #ifdef HAVE_DTRACE_H
531 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
532 CodeBuffer *code_buffer,
533 int vep_offset,
534 int trap_offset,
535 int frame_complete,
536 int frame_size) {
537 code_buffer->finalize_oop_references(method);
538 // create nmethod
539 nmethod* nm = NULL;
540 {
541 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
542 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
543 CodeOffsets offsets;
544 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
545 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
546 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
547
548 nm = new (nmethod_size) nmethod(method(), nmethod_size,
549 &offsets, code_buffer, frame_size);
550
551 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
552 if (PrintAssembly && nm != NULL) {
553 Disassembler::decode(nm);
554 }
555 }
556 // verify nmethod
557 debug_only(if (nm) nm->verify();) // might block
558
559 if (nm != NULL) {
560 nm->log_new_nmethod();
561 }
562
563 return nm;
564 }
565
566 #endif // def HAVE_DTRACE_H
567
568 nmethod* nmethod::new_nmethod(methodHandle method,
569 int compile_id,
570 int entry_bci,
571 CodeOffsets* offsets,
572 int orig_pc_offset,
573 DebugInformationRecorder* debug_info,
574 Dependencies* dependencies,
575 CodeBuffer* code_buffer, int frame_size,
576 OopMapSet* oop_maps,
577 ExceptionHandlerTable* handler_table,
578 ImplicitExceptionTable* nul_chk_table,
579 AbstractCompiler* compiler,
580 int comp_level
581 )
582 {
583 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
584 code_buffer->finalize_oop_references(method);
585 // create nmethod
586 nmethod* nm = NULL;
587 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
588 int nmethod_size =
589 allocation_size(code_buffer, sizeof(nmethod))
590 + adjust_pcs_size(debug_info->pcs_size())
591 + round_to(dependencies->size_in_bytes() , oopSize)
592 + round_to(handler_table->size_in_bytes(), oopSize)
593 + round_to(nul_chk_table->size_in_bytes(), oopSize)
594 + round_to(debug_info->data_size() , oopSize);
595
596 nm = new (nmethod_size)
597 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
598 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
599 oop_maps,
600 handler_table,
601 nul_chk_table,
602 compiler,
603 comp_level);
604
605 if (nm != NULL) {
606 // To make dependency checking during class loading fast, record
607 // the nmethod dependencies in the classes it is dependent on.
608 // This allows the dependency checking code to simply walk the
609 // class hierarchy above the loaded class, checking only nmethods
610 // which are dependent on those classes. The slow way is to
611 // check every nmethod for dependencies which makes it linear in
612 // the number of methods compiled. For applications with a lot
613 // classes the slow way is too slow.
614 for (Dependencies::DepStream deps(nm); deps.next(); ) {
615 Klass* klass = deps.context_type();
616 if (klass == NULL) {
617 continue; // ignore things like evol_method
618 }
619
620 // record this nmethod as dependent on this klass
621 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
622 }
623 }
624 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
625 if (PrintAssembly && nm != NULL) {
626 Disassembler::decode(nm);
627 }
628 }
629
630 // verify nmethod
631 debug_only(if (nm) nm->verify();) // might block
632
633 if (nm != NULL) {
634 nm->log_new_nmethod();
635 }
636
637 // done
638 return nm;
639 }
640
641
642 // For native wrappers
643 nmethod::nmethod(
644 Method* method,
645 int nmethod_size,
646 int compile_id,
647 CodeOffsets* offsets,
648 CodeBuffer* code_buffer,
649 int frame_size,
650 ByteSize basic_lock_owner_sp_offset,
651 ByteSize basic_lock_sp_offset,
652 OopMapSet* oop_maps )
653 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
654 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
655 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
656 _native_basic_lock_sp_offset(basic_lock_sp_offset)
657 {
658 {
659 debug_only(No_Safepoint_Verifier nsv;)
660 assert_locked_or_safepoint(CodeCache_lock);
661
662 init_defaults();
663 _method = method;
664 _entry_bci = InvocationEntryBci;
665 // We have no exception handler or deopt handler make the
666 // values something that will never match a pc like the nmethod vtable entry
667 _exception_offset = 0;
668 _deoptimize_offset = 0;
669 _deoptimize_mh_offset = 0;
670 _orig_pc_offset = 0;
671
672 _consts_offset = data_offset();
673 _stub_offset = data_offset();
674 _oops_offset = data_offset();
675 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
676 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
677 _scopes_pcs_offset = _scopes_data_offset;
678 _dependencies_offset = _scopes_pcs_offset;
679 _handler_table_offset = _dependencies_offset;
680 _nul_chk_table_offset = _handler_table_offset;
681 _nmethod_end_offset = _nul_chk_table_offset;
682 _compile_id = compile_id;
683 _comp_level = CompLevel_none;
684 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
685 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
686 _osr_entry_point = NULL;
687 _exception_cache = NULL;
688 _pc_desc_cache.reset_to(NULL);
689
690 code_buffer->copy_values_to(this);
691 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
692 CodeCache::add_scavenge_root_nmethod(this);
693 Universe::heap()->register_nmethod(this);
694 }
695 debug_only(verify_scavenge_root_oops());
696 CodeCache::commit(this);
697 }
698
699 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
700 ttyLocker ttyl; // keep the following output all in one block
701 // This output goes directly to the tty, not the compiler log.
702 // To enable tools to match it up with the compilation activity,
703 // be sure to tag this tty output with the compile ID.
704 if (xtty != NULL) {
705 xtty->begin_head("print_native_nmethod");
706 xtty->method(_method);
707 xtty->stamp();
708 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
709 }
710 // print the header part first
711 print();
712 // then print the requested information
713 if (PrintNativeNMethods) {
714 print_code();
715 if (oop_maps != NULL) {
716 oop_maps->print();
717 }
718 }
719 if (PrintRelocations) {
720 print_relocations();
721 }
722 if (xtty != NULL) {
723 xtty->tail("print_native_nmethod");
724 }
725 }
726 }
727
728 // For dtrace wrappers
729 #ifdef HAVE_DTRACE_H
730 nmethod::nmethod(
731 Method* method,
732 int nmethod_size,
733 CodeOffsets* offsets,
734 CodeBuffer* code_buffer,
735 int frame_size)
736 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
737 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
738 _native_receiver_sp_offset(in_ByteSize(-1)),
739 _native_basic_lock_sp_offset(in_ByteSize(-1))
740 {
741 {
742 debug_only(No_Safepoint_Verifier nsv;)
743 assert_locked_or_safepoint(CodeCache_lock);
744
745 init_defaults();
746 _method = method;
747 _entry_bci = InvocationEntryBci;
748 // We have no exception handler or deopt handler make the
749 // values something that will never match a pc like the nmethod vtable entry
750 _exception_offset = 0;
751 _deoptimize_offset = 0;
752 _deoptimize_mh_offset = 0;
753 _unwind_handler_offset = -1;
754 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
755 _orig_pc_offset = 0;
756 _consts_offset = data_offset();
757 _stub_offset = data_offset();
758 _oops_offset = data_offset();
759 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
760 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
761 _scopes_pcs_offset = _scopes_data_offset;
762 _dependencies_offset = _scopes_pcs_offset;
763 _handler_table_offset = _dependencies_offset;
764 _nul_chk_table_offset = _handler_table_offset;
765 _nmethod_end_offset = _nul_chk_table_offset;
766 _compile_id = 0; // default
767 _comp_level = CompLevel_none;
768 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
769 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
770 _osr_entry_point = NULL;
771 _exception_cache = NULL;
772 _pc_desc_cache.reset_to(NULL);
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
846 // Section offsets
847 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
848 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
849
850 // Exception handler and deopt handler are in the stub section
851 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
852 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
853 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
854 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
855 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
856 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
857 } else {
858 _deoptimize_mh_offset = -1;
859 }
860 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
861 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
862 } else {
863 _unwind_handler_offset = -1;
864 }
865
866 _oops_offset = data_offset();
867 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
868 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
869
870 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
871 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
872 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
873 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
874 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
875
876 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
877 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
878 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
879 _exception_cache = NULL;
880 _pc_desc_cache.reset_to(scopes_pcs_begin());
881
882 // Copy contents of ScopeDescRecorder to nmethod
883 code_buffer->copy_values_to(this);
884 debug_info->copy_to(this);
885 dependencies->copy_to(this);
886 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
887 CodeCache::add_scavenge_root_nmethod(this);
888 Universe::heap()->register_nmethod(this);
889 }
890 debug_only(verify_scavenge_root_oops());
891
892 CodeCache::commit(this);
893
894 // Copy contents of ExceptionHandlerTable to nmethod
895 handler_table->copy_to(this);
896 nul_chk_table->copy_to(this);
897
898 // we use the information of entry points to find out if a method is
899 // static or non static
900 assert(compiler->is_c2() ||
901 _method->is_static() == (entry_point() == _verified_entry_point),
902 " entry points must be same for static methods and vice versa");
903 }
904
905 bool printnmethods = PrintNMethods
906 || CompilerOracle::should_print(_method)
907 || CompilerOracle::has_option_string(_method, "PrintNMethods");
908 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
909 print_nmethod(printnmethods);
910 }
911 }
912
913
914 // Print a short set of xml attributes to identify this nmethod. The
915 // output should be embedded in some other element.
916 void nmethod::log_identity(xmlStream* log) const {
917 log->print(" compile_id='%d'", compile_id());
918 const char* nm_kind = compile_kind();
919 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
920 if (compiler() != NULL) {
921 log->print(" compiler='%s'", compiler()->name());
922 }
923 if (TieredCompilation) {
924 log->print(" level='%d'", comp_level());
925 }
926 }
927
928
929 #define LOG_OFFSET(log, name) \
930 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
931 log->print(" " XSTR(name) "_offset='%d'" , \
932 (intptr_t)name##_begin() - (intptr_t)this)
933
934
935 void nmethod::log_new_nmethod() const {
936 if (LogCompilation && xtty != NULL) {
937 ttyLocker ttyl;
938 HandleMark hm;
939 xtty->begin_elem("nmethod");
940 log_identity(xtty);
941 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
942 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
943
944 LOG_OFFSET(xtty, relocation);
945 LOG_OFFSET(xtty, consts);
946 LOG_OFFSET(xtty, insts);
947 LOG_OFFSET(xtty, stub);
948 LOG_OFFSET(xtty, scopes_data);
949 LOG_OFFSET(xtty, scopes_pcs);
950 LOG_OFFSET(xtty, dependencies);
951 LOG_OFFSET(xtty, handler_table);
952 LOG_OFFSET(xtty, nul_chk_table);
953 LOG_OFFSET(xtty, oops);
954
955 xtty->method(method());
956 xtty->stamp();
957 xtty->end_elem();
958 }
959 }
960
961 #undef LOG_OFFSET
962
963
964 // Print out more verbose output usually for a newly created nmethod.
965 void nmethod::print_on(outputStream* st, const char* msg) const {
966 if (st != NULL) {
967 ttyLocker ttyl;
968 if (WizardMode) {
969 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
970 st->print_cr(" (" INTPTR_FORMAT ")", this);
971 } else {
972 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
973 }
974 }
975 }
976
977
978 void nmethod::print_nmethod(bool printmethod) {
979 ttyLocker ttyl; // keep the following output all in one block
980 if (xtty != NULL) {
981 xtty->begin_head("print_nmethod");
982 xtty->stamp();
983 xtty->end_head();
984 }
985 // print the header part first
986 print();
987 // then print the requested information
988 if (printmethod) {
989 print_code();
990 print_pcs();
991 if (oop_maps()) {
992 oop_maps()->print();
993 }
994 }
995 if (PrintDebugInfo) {
996 print_scopes();
997 }
998 if (PrintRelocations) {
999 print_relocations();
1000 }
1001 if (PrintDependencies) {
1002 print_dependencies();
1003 }
1004 if (PrintExceptionHandlers) {
1005 print_handler_table();
1006 print_nul_chk_table();
1007 }
1008 if (xtty != NULL) {
1009 xtty->tail("print_nmethod");
1010 }
1011 }
1012
1013
1014 // Promote one word from an assembly-time handle to a live embedded oop.
1015 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1016 if (handle == NULL ||
1017 // As a special case, IC oops are initialized to 1 or -1.
1018 handle == (jobject) Universe::non_oop_word()) {
1019 (*dest) = (oop) handle;
1020 } else {
1021 (*dest) = JNIHandles::resolve_non_null(handle);
1022 }
1023 }
1024
1025
1026 // Have to have the same name because it's called by a template
1027 void nmethod::copy_values(GrowableArray<jobject>* array) {
1028 int length = array->length();
1029 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1030 oop* dest = oops_begin();
1031 for (int index = 0 ; index < length; index++) {
1032 initialize_immediate_oop(&dest[index], array->at(index));
1033 }
1034
1035 // Now we can fix up all the oops in the code. We need to do this
1036 // in the code because the assembler uses jobjects as placeholders.
1037 // The code and relocations have already been initialized by the
1038 // CodeBlob constructor, so it is valid even at this early point to
1039 // iterate over relocations and patch the code.
1040 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1041 }
1042
1043 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1044 int length = array->length();
1045 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1046 Metadata** dest = metadata_begin();
1047 for (int index = 0 ; index < length; index++) {
1048 dest[index] = array->at(index);
1049 }
1050 }
1051
1052 bool nmethod::is_at_poll_return(address pc) {
1053 RelocIterator iter(this, pc, pc+1);
1054 while (iter.next()) {
1055 if (iter.type() == relocInfo::poll_return_type)
1056 return true;
1057 }
1058 return false;
1059 }
1060
1061
1062 bool nmethod::is_at_poll_or_poll_return(address pc) {
1063 RelocIterator iter(this, pc, pc+1);
1064 while (iter.next()) {
1065 relocInfo::relocType t = iter.type();
1066 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1067 return true;
1068 }
1069 return false;
1070 }
1071
1072
1073 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1074 // re-patch all oop-bearing instructions, just in case some oops moved
1075 RelocIterator iter(this, begin, end);
1076 while (iter.next()) {
1077 if (iter.type() == relocInfo::oop_type) {
1078 oop_Relocation* reloc = iter.oop_reloc();
1079 if (initialize_immediates && reloc->oop_is_immediate()) {
1080 oop* dest = reloc->oop_addr();
1081 initialize_immediate_oop(dest, (jobject) *dest);
1082 }
1083 // Refresh the oop-related bits of this instruction.
1084 reloc->fix_oop_relocation();
1085 } else if (iter.type() == relocInfo::metadata_type) {
1086 metadata_Relocation* reloc = iter.metadata_reloc();
1087 reloc->fix_metadata_relocation();
1088 }
1089 }
1090 }
1091
1092
1093 void nmethod::verify_oop_relocations() {
1094 // Ensure sure that the code matches the current oop values
1095 RelocIterator iter(this, NULL, NULL);
1096 while (iter.next()) {
1097 if (iter.type() == relocInfo::oop_type) {
1098 oop_Relocation* reloc = iter.oop_reloc();
1099 if (!reloc->oop_is_immediate()) {
1100 reloc->verify_oop_relocation();
1101 }
1102 }
1103 }
1104 }
1105
1106
1107 ScopeDesc* nmethod::scope_desc_at(address pc) {
1108 PcDesc* pd = pc_desc_at(pc);
1109 guarantee(pd != NULL, "scope must be present");
1110 return new ScopeDesc(this, pd->scope_decode_offset(),
1111 pd->obj_decode_offset(), pd->should_reexecute(),
1112 pd->return_oop());
1113 }
1114
1115
1116 void nmethod::clear_inline_caches() {
1117 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1118 if (is_zombie()) {
1119 return;
1120 }
1121
1122 RelocIterator iter(this);
1123 while (iter.next()) {
1124 iter.reloc()->clear_inline_cache();
1125 }
1126 }
1127
1128
1129 void nmethod::cleanup_inline_caches() {
1130
1131 assert_locked_or_safepoint(CompiledIC_lock);
1132
1133 // If the method is not entrant or zombie then a JMP is plastered over the
1134 // first few bytes. If an oop in the old code was there, that oop
1135 // should not get GC'd. Skip the first few bytes of oops on
1136 // not-entrant methods.
1137 address low_boundary = verified_entry_point();
1138 if (!is_in_use()) {
1139 low_boundary += NativeJump::instruction_size;
1140 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1141 // This means that the low_boundary is going to be a little too high.
1142 // This shouldn't matter, since oops of non-entrant methods are never used.
1143 // In fact, why are we bothering to look at oops in a non-entrant method??
1144 }
1145
1146 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1147 ResourceMark rm;
1148 RelocIterator iter(this, low_boundary);
1149 while(iter.next()) {
1150 switch(iter.type()) {
1151 case relocInfo::virtual_call_type:
1152 case relocInfo::opt_virtual_call_type: {
1153 CompiledIC *ic = CompiledIC_at(iter.reloc());
1154 // Ok, to lookup references to zombies here
1155 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1156 if( cb != NULL && cb->is_nmethod() ) {
1157 nmethod* nm = (nmethod*)cb;
1158 // Clean inline caches pointing to both zombie and not_entrant methods
1159 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1160 }
1161 break;
1162 }
1163 case relocInfo::static_call_type: {
1164 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1165 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1166 if( cb != NULL && cb->is_nmethod() ) {
1167 nmethod* nm = (nmethod*)cb;
1168 // Clean inline caches pointing to both zombie and not_entrant methods
1169 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1170 }
1171 break;
1172 }
1173 }
1174 }
1175 }
1176
1177 // This is a private interface with the sweeper.
1178 void nmethod::mark_as_seen_on_stack() {
1179 assert(is_not_entrant(), "must be a non-entrant method");
1180 // Set the traversal mark to ensure that the sweeper does 2
1181 // cleaning passes before moving to zombie.
1182 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1183 }
1184
1185 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1186 // there are no activations on the stack, not in use by the VM,
1187 // and not in use by the ServiceThread)
1188 bool nmethod::can_not_entrant_be_converted() {
1189 assert(is_not_entrant(), "must be a non-entrant method");
1190
1191 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1192 // count can be greater than the stack traversal count before it hits the
1193 // nmethod for the second time.
1194 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1195 !is_locked_by_vm();
1196 }
1197
1198 void nmethod::inc_decompile_count() {
1199 if (!is_compiled_by_c2()) return;
1200 // Could be gated by ProfileTraps, but do not bother...
1201 Method* m = method();
1202 if (m == NULL) return;
1203 MethodData* mdo = m->method_data();
1204 if (mdo == NULL) return;
1205 // There is a benign race here. See comments in methodData.hpp.
1206 mdo->inc_decompile_count();
1207 }
1208
1209 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1210
1211 post_compiled_method_unload();
1212
1213 // Since this nmethod is being unloaded, make sure that dependencies
1214 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1215 // indicate that this work is being done during a GC.
1216 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1217 assert(is_alive != NULL, "Should be non-NULL");
1218 // A non-NULL is_alive closure indicates that this is being called during GC.
1219 flush_dependencies(is_alive);
1220
1221 // Break cycle between nmethod & method
1222 if (TraceClassUnloading && WizardMode) {
1223 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1224 " unloadable], Method*(" INTPTR_FORMAT
1225 "), cause(" INTPTR_FORMAT ")",
1226 this, (address)_method, (address)cause);
1227 if (!Universe::heap()->is_gc_active())
1228 cause->klass()->print();
1229 }
1230 // Unlink the osr method, so we do not look this up again
1231 if (is_osr_method()) {
1232 invalidate_osr_method();
1233 }
1234 // If _method is already NULL the Method* is about to be unloaded,
1235 // so we don't have to break the cycle. Note that it is possible to
1236 // have the Method* live here, in case we unload the nmethod because
1237 // it is pointing to some oop (other than the Method*) being unloaded.
1238 if (_method != NULL) {
1239 // OSR methods point to the Method*, but the Method* does not
1240 // point back!
1241 if (_method->code() == this) {
1242 _method->clear_code(); // Break a cycle
1243 }
1244 _method = NULL; // Clear the method of this dead nmethod
1245 }
1246 // Make the class unloaded - i.e., change state and notify sweeper
1247 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1248 if (is_in_use()) {
1249 // Transitioning directly from live to unloaded -- so
1250 // we need to force a cache clean-up; remember this
1251 // for later on.
1252 CodeCache::set_needs_cache_clean(true);
1253 }
1254 _state = unloaded;
1255
1256 // Log the unloading.
1257 log_state_change();
1258
1259 // The Method* is gone at this point
1260 assert(_method == NULL, "Tautology");
1261
1262 set_osr_link(NULL);
1263 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1264 NMethodSweeper::notify(this);
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 // The state of nmethods that are currently locked by the VM must not change.
1304 // Some operations such as setting ICs (e.g., SharedRuntime::resolve_sub_helper())
1305 // rely on this fact.
1306 if (is_locked_by_vm()) {
1307 return false;
1308 }
1309
1310 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1311 nmethodLocker nml(this);
1312 methodHandle the_method(method());
1313 No_Safepoint_Verifier nsv;
1314
1315 // during patching, depending on the nmethod state we must notify the GC that
1316 // code has been unloaded, unregistering it. We cannot do this right while
1317 // holding the Patching_lock because we need to use the CodeCache_lock. This
1318 // would be prone to deadlocks.
1319 // This flag is used to remember whether we need to later lock and unregister.
1320 bool nmethod_needs_unregister = false;
1321
1322 {
1323 // invalidate osr nmethod before acquiring the patching lock since
1324 // they both acquire leaf locks and we don't want a deadlock.
1325 // This logic is equivalent to the logic below for patching the
1326 // verified entry point of regular methods.
1327 if (is_osr_method()) {
1328 // this effectively makes the osr nmethod not entrant
1329 invalidate_osr_method();
1330 }
1331
1332 // Enter critical section. Does not block for safepoint.
1333 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1334
1335 if (_state == state) {
1336 // another thread already performed this transition so nothing
1337 // to do, but return false to indicate this.
1338 return false;
1339 }
1340
1341 // The caller can be calling the method statically or through an inline
1342 // cache call.
1343 if (!is_osr_method() && !is_not_entrant()) {
1344 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1345 SharedRuntime::get_handle_wrong_method_stub());
1346 }
1347
1348 if (is_in_use()) {
1349 // It's a true state change, so mark the method as decompiled.
1350 // Do it only for transition from alive.
1351 inc_decompile_count();
1352 }
1353
1354 // If the state is becoming a zombie, signal to unregister the nmethod with
1355 // the heap.
1356 // This nmethod may have already been unloaded during a full GC.
1357 if ((state == zombie) && !is_unloaded()) {
1358 nmethod_needs_unregister = true;
1359 }
1360
1361 // Change state
1362 _state = state;
1363
1364 // Log the transition once
1365 log_state_change();
1366
1367 // Remove nmethod from method.
1368 // We need to check if both the _code and _from_compiled_code_entry_point
1369 // refer to this nmethod because there is a race in setting these two fields
1370 // in Method* as seen in bugid 4947125.
1371 // If the vep() points to the zombie nmethod, the memory for the nmethod
1372 // could be flushed and the compiler and vtable stubs could still call
1373 // through it.
1374 if (method() != NULL && (method()->code() == this ||
1375 method()->from_compiled_entry() == verified_entry_point())) {
1376 HandleMark hm;
1377 method()->clear_code();
1378 }
1379
1380 if (state == not_entrant) {
1381 mark_as_seen_on_stack();
1382 }
1383
1384 } // leave critical region under Patching_lock
1385
1386 // When the nmethod becomes zombie it is no longer alive so the
1387 // dependencies must be flushed. nmethods in the not_entrant
1388 // state will be flushed later when the transition to zombie
1389 // happens or they get unloaded.
1390 if (state == zombie) {
1391 {
1392 // Flushing dependecies must be done before any possible
1393 // safepoint can sneak in, otherwise the oops used by the
1394 // dependency logic could have become stale.
1395 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1396 if (nmethod_needs_unregister) {
1397 Universe::heap()->unregister_nmethod(this);
1398 }
1399 flush_dependencies(NULL);
1400 }
1401
1402 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1403 // event and it hasn't already been reported for this nmethod then
1404 // report it now. The event may have been reported earilier if the GC
1405 // marked it for unloading). JvmtiDeferredEventQueue support means
1406 // we no longer go to a safepoint here.
1407 post_compiled_method_unload();
1408
1409 #ifdef ASSERT
1410 // It's no longer safe to access the oops section since zombie
1411 // nmethods aren't scanned for GC.
1412 _oops_are_stale = true;
1413 #endif
1414 // the Method may be reclaimed by class unloading now that the
1415 // nmethod is in zombie state
1416 set_method(NULL);
1417 } else {
1418 assert(state == not_entrant, "other cases may need to be handled differently");
1419 }
1420
1421 if (TraceCreateZombies) {
1422 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1423 }
1424
1425 // Make sweeper aware that there is a zombie method that needs to be removed
1426 NMethodSweeper::notify(this);
1427 return true;
1428 }
1429
1430 void nmethod::flush() {
1431 // Note that there are no valid oops in the nmethod anymore.
1432 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1433 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1434
1435 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1436 assert_locked_or_safepoint(CodeCache_lock);
1437
1438 // completely deallocate this method
1439 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1440 if (PrintMethodFlushing) {
1441 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1442 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
1443 }
1444
1445 // We need to deallocate any ExceptionCache data.
1446 // Note that we do not need to grab the nmethod lock for this, it
1447 // better be thread safe if we're disposing of it!
1448 ExceptionCache* ec = exception_cache();
1449 set_exception_cache(NULL);
1450 while(ec != NULL) {
1451 ExceptionCache* next = ec->next();
1452 delete ec;
1453 ec = next;
1454 }
1455
1456 if (on_scavenge_root_list()) {
1457 CodeCache::drop_scavenge_root_nmethod(this);
1458 }
1459
1460 if (is_speculatively_disconnected()) {
1461 CodeCache::remove_saved_code(this);
1462 }
1463
1464 #ifdef SHARK
1465 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1466 #endif // SHARK
1467
1468 ((CodeBlob*)(this))->flush();
1469
1470 CodeCache::free(this);
1471 }
1472
1473
1474 //
1475 // Notify all classes this nmethod is dependent on that it is no
1476 // longer dependent. This should only be called in two situations.
1477 // First, when a nmethod transitions to a zombie all dependents need
1478 // to be clear. Since zombification happens at a safepoint there's no
1479 // synchronization issues. The second place is a little more tricky.
1480 // During phase 1 of mark sweep class unloading may happen and as a
1481 // result some nmethods may get unloaded. In this case the flushing
1482 // of dependencies must happen during phase 1 since after GC any
1483 // dependencies in the unloaded nmethod won't be updated, so
1484 // traversing the dependency information in unsafe. In that case this
1485 // function is called with a non-NULL argument and this function only
1486 // notifies instanceKlasses that are reachable
1487
1488 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1489 assert_locked_or_safepoint(CodeCache_lock);
1490 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1491 "is_alive is non-NULL if and only if we are called during GC");
1492 if (!has_flushed_dependencies()) {
1493 set_has_flushed_dependencies();
1494 for (Dependencies::DepStream deps(this); deps.next(); ) {
1495 Klass* klass = deps.context_type();
1496 if (klass == NULL) continue; // ignore things like evol_method
1497
1498 // During GC the is_alive closure is non-NULL, and is used to
1499 // determine liveness of dependees that need to be updated.
1500 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1501 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1502 }
1503 }
1504 }
1505 }
1506
1507
1508 // If this oop is not live, the nmethod can be unloaded.
1509 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1510 assert(root != NULL, "just checking");
1511 oop obj = *root;
1512 if (obj == NULL || is_alive->do_object_b(obj)) {
1513 return false;
1514 }
1515
1516 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1517 // simply because one of its constant oops has gone dead.
1518 // No actual classes need to be unloaded in order for this to occur.
1519 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1520 make_unloaded(is_alive, obj);
1521 return true;
1522 }
1523
1524 // ------------------------------------------------------------------
1525 // post_compiled_method_load_event
1526 // new method for install_code() path
1527 // Transfer information from compilation to jvmti
1528 void nmethod::post_compiled_method_load_event() {
1529
1530 Method* moop = method();
1531 #ifndef USDT2
1532 HS_DTRACE_PROBE8(hotspot, compiled__method__load,
1533 moop->klass_name()->bytes(),
1534 moop->klass_name()->utf8_length(),
1535 moop->name()->bytes(),
1536 moop->name()->utf8_length(),
1537 moop->signature()->bytes(),
1538 moop->signature()->utf8_length(),
1539 insts_begin(), insts_size());
1540 #else /* USDT2 */
1541 HOTSPOT_COMPILED_METHOD_LOAD(
1542 (char *) moop->klass_name()->bytes(),
1543 moop->klass_name()->utf8_length(),
1544 (char *) moop->name()->bytes(),
1545 moop->name()->utf8_length(),
1546 (char *) moop->signature()->bytes(),
1547 moop->signature()->utf8_length(),
1548 insts_begin(), insts_size());
1549 #endif /* USDT2 */
1550
1551 if (JvmtiExport::should_post_compiled_method_load() ||
1552 JvmtiExport::should_post_compiled_method_unload()) {
1553 get_and_cache_jmethod_id();
1554 }
1555
1556 if (JvmtiExport::should_post_compiled_method_load()) {
1557 // Let the Service thread (which is a real Java thread) post the event
1558 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1559 JvmtiDeferredEventQueue::enqueue(
1560 JvmtiDeferredEvent::compiled_method_load_event(this));
1561 }
1562 }
1563
1564 jmethodID nmethod::get_and_cache_jmethod_id() {
1565 if (_jmethod_id == NULL) {
1566 // Cache the jmethod_id since it can no longer be looked up once the
1567 // method itself has been marked for unloading.
1568 _jmethod_id = method()->jmethod_id();
1569 }
1570 return _jmethod_id;
1571 }
1572
1573 void nmethod::post_compiled_method_unload() {
1574 if (unload_reported()) {
1575 // During unloading we transition to unloaded and then to zombie
1576 // and the unloading is reported during the first transition.
1577 return;
1578 }
1579
1580 assert(_method != NULL && !is_unloaded(), "just checking");
1581 DTRACE_METHOD_UNLOAD_PROBE(method());
1582
1583 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1584 // post the event. Sometime later this nmethod will be made a zombie
1585 // by the sweeper but the Method* will not be valid at that point.
1586 // If the _jmethod_id is null then no load event was ever requested
1587 // so don't bother posting the unload. The main reason for this is
1588 // that the jmethodID is a weak reference to the Method* so if
1589 // it's being unloaded there's no way to look it up since the weak
1590 // ref will have been cleared.
1591 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1592 assert(!unload_reported(), "already unloaded");
1593 JvmtiDeferredEvent event =
1594 JvmtiDeferredEvent::compiled_method_unload_event(this,
1595 _jmethod_id, insts_begin());
1596 if (SafepointSynchronize::is_at_safepoint()) {
1597 // Don't want to take the queueing lock. Add it as pending and
1598 // it will get enqueued later.
1599 JvmtiDeferredEventQueue::add_pending_event(event);
1600 } else {
1601 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1602 JvmtiDeferredEventQueue::enqueue(event);
1603 }
1604 }
1605
1606 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1607 // any time. As the nmethod is being unloaded now we mark it has
1608 // having the unload event reported - this will ensure that we don't
1609 // attempt to report the event in the unlikely scenario where the
1610 // event is enabled at the time the nmethod is made a zombie.
1611 set_unload_reported();
1612 }
1613
1614 // This is called at the end of the strong tracing/marking phase of a
1615 // GC to unload an nmethod if it contains otherwise unreachable
1616 // oops.
1617
1618 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1619 // Make sure the oop's ready to receive visitors
1620 assert(!is_zombie() && !is_unloaded(),
1621 "should not call follow on zombie or unloaded nmethod");
1622
1623 // If the method is not entrant then a JMP is plastered over the
1624 // first few bytes. If an oop in the old code was there, that oop
1625 // should not get GC'd. Skip the first few bytes of oops on
1626 // not-entrant methods.
1627 address low_boundary = verified_entry_point();
1628 if (is_not_entrant()) {
1629 low_boundary += NativeJump::instruction_size;
1630 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1631 // (See comment above.)
1632 }
1633
1634 // The RedefineClasses() API can cause the class unloading invariant
1635 // to no longer be true. See jvmtiExport.hpp for details.
1636 // Also, leave a debugging breadcrumb in local flag.
1637 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1638 if (a_class_was_redefined) {
1639 // This set of the unloading_occurred flag is done before the
1640 // call to post_compiled_method_unload() so that the unloading
1641 // of this nmethod is reported.
1642 unloading_occurred = true;
1643 }
1644
1645 // Exception cache
1646 ExceptionCache* ec = exception_cache();
1647 while (ec != NULL) {
1648 Klass* ex_klass = ec->exception_type();
1649 ExceptionCache* next_ec = ec->next();
1650 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
1651 remove_from_exception_cache(ec);
1652 }
1653 ec = next_ec;
1654 }
1655
1656 // If class unloading occurred we first iterate over all inline caches and
1657 // clear ICs where the cached oop is referring to an unloaded klass or method.
1658 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1659 // iteration below.
1660 if (unloading_occurred) {
1661 RelocIterator iter(this, low_boundary);
1662 while(iter.next()) {
1663 if (iter.type() == relocInfo::virtual_call_type) {
1664 CompiledIC *ic = CompiledIC_at(iter.reloc());
1665 if (ic->is_icholder_call()) {
1666 // The only exception is compiledICHolder oops which may
1667 // yet be marked below. (We check this further below).
1668 CompiledICHolder* cichk_oop = ic->cached_icholder();
1669 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1670 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1671 continue;
1672 }
1673 } else {
1674 Metadata* ic_oop = ic->cached_metadata();
1675 if (ic_oop != NULL) {
1676 if (ic_oop->is_klass()) {
1677 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1678 continue;
1679 }
1680 } else if (ic_oop->is_method()) {
1681 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1682 continue;
1683 }
1684 } else {
1685 ShouldNotReachHere();
1686 }
1687 }
1688 }
1689 ic->set_to_clean();
1690 }
1691 }
1692 }
1693
1694 // Compiled code
1695 {
1696 RelocIterator iter(this, low_boundary);
1697 while (iter.next()) {
1698 if (iter.type() == relocInfo::oop_type) {
1699 oop_Relocation* r = iter.oop_reloc();
1700 // In this loop, we must only traverse those oops directly embedded in
1701 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1702 assert(1 == (r->oop_is_immediate()) +
1703 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1704 "oop must be found in exactly one place");
1705 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1706 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1707 return;
1708 }
1709 }
1710 }
1711 }
1712 }
1713
1714
1715 // Scopes
1716 for (oop* p = oops_begin(); p < oops_end(); p++) {
1717 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1718 if (can_unload(is_alive, p, unloading_occurred)) {
1719 return;
1720 }
1721 }
1722
1723 // Ensure that all metadata is still alive
1724 verify_metadata_loaders(low_boundary, is_alive);
1725 }
1726
1727 #ifdef ASSERT
1728
1729 class CheckClass : AllStatic {
1730 static BoolObjectClosure* _is_alive;
1731
1732 // Check class_loader is alive for this bit of metadata.
1733 static void check_class(Metadata* md) {
1734 Klass* klass = NULL;
1735 if (md->is_klass()) {
1736 klass = ((Klass*)md);
1737 } else if (md->is_method()) {
1738 klass = ((Method*)md)->method_holder();
1739 } else if (md->is_methodData()) {
1740 klass = ((MethodData*)md)->method()->method_holder();
1741 } else {
1742 md->print();
1743 ShouldNotReachHere();
1744 }
1745 assert(klass->is_loader_alive(_is_alive), "must be alive");
1746 }
1747 public:
1748 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
1749 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
1750 _is_alive = is_alive;
1751 nm->metadata_do(check_class);
1752 }
1753 };
1754
1755 // This is called during a safepoint so can use static data
1756 BoolObjectClosure* CheckClass::_is_alive = NULL;
1757 #endif // ASSERT
1758
1759
1760 // Processing of oop references should have been sufficient to keep
1761 // all strong references alive. Any weak references should have been
1762 // cleared as well. Visit all the metadata and ensure that it's
1763 // really alive.
1764 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
1765 #ifdef ASSERT
1766 RelocIterator iter(this, low_boundary);
1767 while (iter.next()) {
1768 // static_stub_Relocations may have dangling references to
1769 // Method*s so trim them out here. Otherwise it looks like
1770 // compiled code is maintaining a link to dead metadata.
1771 address static_call_addr = NULL;
1772 if (iter.type() == relocInfo::opt_virtual_call_type) {
1773 CompiledIC* cic = CompiledIC_at(iter.reloc());
1774 if (!cic->is_call_to_interpreted()) {
1775 static_call_addr = iter.addr();
1776 }
1777 } else if (iter.type() == relocInfo::static_call_type) {
1778 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
1779 if (!csc->is_call_to_interpreted()) {
1780 static_call_addr = iter.addr();
1781 }
1782 }
1783 if (static_call_addr != NULL) {
1784 RelocIterator sciter(this, low_boundary);
1785 while (sciter.next()) {
1786 if (sciter.type() == relocInfo::static_stub_type &&
1787 sciter.static_stub_reloc()->static_call() == static_call_addr) {
1788 sciter.static_stub_reloc()->clear_inline_cache();
1789 }
1790 }
1791 }
1792 }
1793 // Check that the metadata embedded in the nmethod is alive
1794 CheckClass::do_check_class(is_alive, this);
1795 #endif
1796 }
1797
1798
1799 // Iterate over metadata calling this function. Used by RedefineClasses
1800 void nmethod::metadata_do(void f(Metadata*)) {
1801 address low_boundary = verified_entry_point();
1802 if (is_not_entrant()) {
1803 low_boundary += NativeJump::instruction_size;
1804 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1805 // (See comment above.)
1806 }
1807 {
1808 // Visit all immediate references that are embedded in the instruction stream.
1809 RelocIterator iter(this, low_boundary);
1810 while (iter.next()) {
1811 if (iter.type() == relocInfo::metadata_type ) {
1812 metadata_Relocation* r = iter.metadata_reloc();
1813 // In this lmetadata, we must only follow those metadatas directly embedded in
1814 // the code. Other metadatas (oop_index>0) are seen as part of
1815 // the metadata section below.
1816 assert(1 == (r->metadata_is_immediate()) +
1817 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1818 "metadata must be found in exactly one place");
1819 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1820 Metadata* md = r->metadata_value();
1821 f(md);
1822 }
1823 } else if (iter.type() == relocInfo::virtual_call_type) {
1824 // Check compiledIC holders associated with this nmethod
1825 CompiledIC *ic = CompiledIC_at(iter.reloc());
1826 if (ic->is_icholder_call()) {
1827 CompiledICHolder* cichk = ic->cached_icholder();
1828 f(cichk->holder_method());
1829 f(cichk->holder_klass());
1830 } else {
1831 Metadata* ic_oop = ic->cached_metadata();
1832 if (ic_oop != NULL) {
1833 f(ic_oop);
1834 }
1835 }
1836 }
1837 }
1838 }
1839
1840 // Visit the metadata section
1841 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1842 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
1843 Metadata* md = *p;
1844 f(md);
1845 }
1846
1847 // Call function Method*, not embedded in these other places.
1848 if (_method != NULL) f(_method);
1849 }
1850
1851 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1852 // make sure the oops ready to receive visitors
1853 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1854 assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1855
1856 // If the method is not entrant or zombie then a JMP is plastered over the
1857 // first few bytes. If an oop in the old code was there, that oop
1858 // should not get GC'd. Skip the first few bytes of oops on
1859 // not-entrant methods.
1860 address low_boundary = verified_entry_point();
1861 if (is_not_entrant()) {
1862 low_boundary += NativeJump::instruction_size;
1863 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1864 // (See comment above.)
1865 }
1866
1867 RelocIterator iter(this, low_boundary);
1868
1869 while (iter.next()) {
1870 if (iter.type() == relocInfo::oop_type ) {
1871 oop_Relocation* r = iter.oop_reloc();
1872 // In this loop, we must only follow those oops directly embedded in
1873 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1874 assert(1 == (r->oop_is_immediate()) +
1875 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1876 "oop must be found in exactly one place");
1877 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1878 f->do_oop(r->oop_addr());
1879 }
1880 }
1881 }
1882
1883 // Scopes
1884 // This includes oop constants not inlined in the code stream.
1885 for (oop* p = oops_begin(); p < oops_end(); p++) {
1886 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1887 f->do_oop(p);
1888 }
1889 }
1890
1891 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1892
1893 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1894
1895 // An nmethod is "marked" if its _mark_link is set non-null.
1896 // Even if it is the end of the linked list, it will have a non-null link value,
1897 // as long as it is on the list.
1898 // This code must be MP safe, because it is used from parallel GC passes.
1899 bool nmethod::test_set_oops_do_mark() {
1900 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1901 nmethod* observed_mark_link = _oops_do_mark_link;
1902 if (observed_mark_link == NULL) {
1903 // Claim this nmethod for this thread to mark.
1904 observed_mark_link = (nmethod*)
1905 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1906 if (observed_mark_link == NULL) {
1907
1908 // Atomically append this nmethod (now claimed) to the head of the list:
1909 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1910 for (;;) {
1911 nmethod* required_mark_nmethods = observed_mark_nmethods;
1912 _oops_do_mark_link = required_mark_nmethods;
1913 observed_mark_nmethods = (nmethod*)
1914 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1915 if (observed_mark_nmethods == required_mark_nmethods)
1916 break;
1917 }
1918 // Mark was clear when we first saw this guy.
1919 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
1920 return false;
1921 }
1922 }
1923 // On fall through, another racing thread marked this nmethod before we did.
1924 return true;
1925 }
1926
1927 void nmethod::oops_do_marking_prologue() {
1928 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
1929 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1930 // We use cmpxchg_ptr instead of regular assignment here because the user
1931 // may fork a bunch of threads, and we need them all to see the same state.
1932 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1933 guarantee(observed == NULL, "no races in this sequential code");
1934 }
1935
1936 void nmethod::oops_do_marking_epilogue() {
1937 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1938 nmethod* cur = _oops_do_mark_nmethods;
1939 while (cur != NMETHOD_SENTINEL) {
1940 assert(cur != NULL, "not NULL-terminated");
1941 nmethod* next = cur->_oops_do_mark_link;
1942 cur->_oops_do_mark_link = NULL;
1943 cur->fix_oop_relocations();
1944 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
1945 cur = next;
1946 }
1947 void* required = _oops_do_mark_nmethods;
1948 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1949 guarantee(observed == required, "no races in this sequential code");
1950 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
1951 }
1952
1953 class DetectScavengeRoot: public OopClosure {
1954 bool _detected_scavenge_root;
1955 public:
1956 DetectScavengeRoot() : _detected_scavenge_root(false)
1957 { NOT_PRODUCT(_print_nm = NULL); }
1958 bool detected_scavenge_root() { return _detected_scavenge_root; }
1959 virtual void do_oop(oop* p) {
1960 if ((*p) != NULL && (*p)->is_scavengable()) {
1961 NOT_PRODUCT(maybe_print(p));
1962 _detected_scavenge_root = true;
1963 }
1964 }
1965 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1966
1967 #ifndef PRODUCT
1968 nmethod* _print_nm;
1969 void maybe_print(oop* p) {
1970 if (_print_nm == NULL) return;
1971 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
1972 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
1973 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
1974 (intptr_t)(*p), (intptr_t)p);
1975 (*p)->print();
1976 }
1977 #endif //PRODUCT
1978 };
1979
1980 bool nmethod::detect_scavenge_root_oops() {
1981 DetectScavengeRoot detect_scavenge_root;
1982 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
1983 oops_do(&detect_scavenge_root);
1984 return detect_scavenge_root.detected_scavenge_root();
1985 }
1986
1987 // Method that knows how to preserve outgoing arguments at call. This method must be
1988 // called with a frame corresponding to a Java invoke
1989 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1990 #ifndef SHARK
1991 if (!method()->is_native()) {
1992 SimpleScopeDesc ssd(this, fr.pc());
1993 Bytecode_invoke call(ssd.method(), ssd.bci());
1994 bool has_receiver = call.has_receiver();
1995 bool has_appendix = call.has_appendix();
1996 Symbol* signature = call.signature();
1997 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
1998 }
1999 #endif // !SHARK
2000 }
2001
2002
2003 oop nmethod::embeddedOop_at(u_char* p) {
2004 RelocIterator iter(this, p, p + 1);
2005 while (iter.next())
2006 if (iter.type() == relocInfo::oop_type) {
2007 return iter.oop_reloc()->oop_value();
2008 }
2009 return NULL;
2010 }
2011
2012
2013 inline bool includes(void* p, void* from, void* to) {
2014 return from <= p && p < to;
2015 }
2016
2017
2018 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2019 assert(count >= 2, "must be sentinel values, at least");
2020
2021 #ifdef ASSERT
2022 // must be sorted and unique; we do a binary search in find_pc_desc()
2023 int prev_offset = pcs[0].pc_offset();
2024 assert(prev_offset == PcDesc::lower_offset_limit,
2025 "must start with a sentinel");
2026 for (int i = 1; i < count; i++) {
2027 int this_offset = pcs[i].pc_offset();
2028 assert(this_offset > prev_offset, "offsets must be sorted");
2029 prev_offset = this_offset;
2030 }
2031 assert(prev_offset == PcDesc::upper_offset_limit,
2032 "must end with a sentinel");
2033 #endif //ASSERT
2034
2035 // Search for MethodHandle invokes and tag the nmethod.
2036 for (int i = 0; i < count; i++) {
2037 if (pcs[i].is_method_handle_invoke()) {
2038 set_has_method_handle_invokes(true);
2039 break;
2040 }
2041 }
2042 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2043
2044 int size = count * sizeof(PcDesc);
2045 assert(scopes_pcs_size() >= size, "oob");
2046 memcpy(scopes_pcs_begin(), pcs, size);
2047
2048 // Adjust the final sentinel downward.
2049 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2050 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2051 last_pc->set_pc_offset(content_size() + 1);
2052 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2053 // Fill any rounding gaps with copies of the last record.
2054 last_pc[1] = last_pc[0];
2055 }
2056 // The following assert could fail if sizeof(PcDesc) is not
2057 // an integral multiple of oopSize (the rounding term).
2058 // If it fails, change the logic to always allocate a multiple
2059 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2060 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2061 }
2062
2063 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2064 assert(scopes_data_size() >= size, "oob");
2065 memcpy(scopes_data_begin(), buffer, size);
2066 }
2067
2068
2069 #ifdef ASSERT
2070 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2071 PcDesc* lower = nm->scopes_pcs_begin();
2072 PcDesc* upper = nm->scopes_pcs_end();
2073 lower += 1; // exclude initial sentinel
2074 PcDesc* res = NULL;
2075 for (PcDesc* p = lower; p < upper; p++) {
2076 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2077 if (match_desc(p, pc_offset, approximate)) {
2078 if (res == NULL)
2079 res = p;
2080 else
2081 res = (PcDesc*) badAddress;
2082 }
2083 }
2084 return res;
2085 }
2086 #endif
2087
2088
2089 // Finds a PcDesc with real-pc equal to "pc"
2090 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2091 address base_address = code_begin();
2092 if ((pc < base_address) ||
2093 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2094 return NULL; // PC is wildly out of range
2095 }
2096 int pc_offset = (int) (pc - base_address);
2097
2098 // Check the PcDesc cache if it contains the desired PcDesc
2099 // (This as an almost 100% hit rate.)
2100 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2101 if (res != NULL) {
2102 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2103 return res;
2104 }
2105
2106 // Fallback algorithm: quasi-linear search for the PcDesc
2107 // Find the last pc_offset less than the given offset.
2108 // The successor must be the required match, if there is a match at all.
2109 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2110 PcDesc* lower = scopes_pcs_begin();
2111 PcDesc* upper = scopes_pcs_end();
2112 upper -= 1; // exclude final sentinel
2113 if (lower >= upper) return NULL; // native method; no PcDescs at all
2114
2115 #define assert_LU_OK \
2116 /* invariant on lower..upper during the following search: */ \
2117 assert(lower->pc_offset() < pc_offset, "sanity"); \
2118 assert(upper->pc_offset() >= pc_offset, "sanity")
2119 assert_LU_OK;
2120
2121 // Use the last successful return as a split point.
2122 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2123 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2124 if (mid->pc_offset() < pc_offset) {
2125 lower = mid;
2126 } else {
2127 upper = mid;
2128 }
2129
2130 // Take giant steps at first (4096, then 256, then 16, then 1)
2131 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2132 const int RADIX = (1 << LOG2_RADIX);
2133 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2134 while ((mid = lower + step) < upper) {
2135 assert_LU_OK;
2136 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2137 if (mid->pc_offset() < pc_offset) {
2138 lower = mid;
2139 } else {
2140 upper = mid;
2141 break;
2142 }
2143 }
2144 assert_LU_OK;
2145 }
2146
2147 // Sneak up on the value with a linear search of length ~16.
2148 while (true) {
2149 assert_LU_OK;
2150 mid = lower + 1;
2151 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2152 if (mid->pc_offset() < pc_offset) {
2153 lower = mid;
2154 } else {
2155 upper = mid;
2156 break;
2157 }
2158 }
2159 #undef assert_LU_OK
2160
2161 if (match_desc(upper, pc_offset, approximate)) {
2162 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2163 _pc_desc_cache.add_pc_desc(upper);
2164 return upper;
2165 } else {
2166 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2167 return NULL;
2168 }
2169 }
2170
2171
2172 bool nmethod::check_all_dependencies() {
2173 bool found_check = false;
2174 // wholesale check of all dependencies
2175 for (Dependencies::DepStream deps(this); deps.next(); ) {
2176 if (deps.check_dependency() != NULL) {
2177 found_check = true;
2178 NOT_DEBUG(break);
2179 }
2180 }
2181 return found_check; // tell caller if we found anything
2182 }
2183
2184 bool nmethod::check_dependency_on(DepChange& changes) {
2185 // What has happened:
2186 // 1) a new class dependee has been added
2187 // 2) dependee and all its super classes have been marked
2188 bool found_check = false; // set true if we are upset
2189 for (Dependencies::DepStream deps(this); deps.next(); ) {
2190 // Evaluate only relevant dependencies.
2191 if (deps.spot_check_dependency_at(changes) != NULL) {
2192 found_check = true;
2193 NOT_DEBUG(break);
2194 }
2195 }
2196 return found_check;
2197 }
2198
2199 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2200 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2201 Array<Method*>* dependee_methods = dependee_ik->methods();
2202 for (Dependencies::DepStream deps(this); deps.next(); ) {
2203 if (deps.type() == Dependencies::evol_method) {
2204 Method* method = deps.method_argument(0);
2205 for (int j = 0; j < dependee_methods->length(); j++) {
2206 if (dependee_methods->at(j) == method) {
2207 // RC_TRACE macro has an embedded ResourceMark
2208 RC_TRACE(0x01000000,
2209 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2210 _method->method_holder()->external_name(),
2211 _method->name()->as_C_string(),
2212 _method->signature()->as_C_string(), compile_id(),
2213 method->method_holder()->external_name(),
2214 method->name()->as_C_string(),
2215 method->signature()->as_C_string()));
2216 if (TraceDependencies || LogCompilation)
2217 deps.log_dependency(dependee);
2218 return true;
2219 }
2220 }
2221 }
2222 }
2223 return false;
2224 }
2225
2226 // Called from mark_for_deoptimization, when dependee is invalidated.
2227 bool nmethod::is_dependent_on_method(Method* dependee) {
2228 for (Dependencies::DepStream deps(this); deps.next(); ) {
2229 if (deps.type() != Dependencies::evol_method)
2230 continue;
2231 Method* method = deps.method_argument(0);
2232 if (method == dependee) return true;
2233 }
2234 return false;
2235 }
2236
2237
2238 bool nmethod::is_patchable_at(address instr_addr) {
2239 assert(insts_contains(instr_addr), "wrong nmethod used");
2240 if (is_zombie()) {
2241 // a zombie may never be patched
2242 return false;
2243 }
2244 return true;
2245 }
2246
2247
2248 address nmethod::continuation_for_implicit_exception(address pc) {
2249 // Exception happened outside inline-cache check code => we are inside
2250 // an active nmethod => use cpc to determine a return address
2251 int exception_offset = pc - code_begin();
2252 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2253 #ifdef ASSERT
2254 if (cont_offset == 0) {
2255 Thread* thread = ThreadLocalStorage::get_thread_slow();
2256 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2257 HandleMark hm(thread);
2258 ResourceMark rm(thread);
2259 CodeBlob* cb = CodeCache::find_blob(pc);
2260 assert(cb != NULL && cb == this, "");
2261 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2262 print();
2263 method()->print_codes();
2264 print_code();
2265 print_pcs();
2266 }
2267 #endif
2268 if (cont_offset == 0) {
2269 // Let the normal error handling report the exception
2270 return NULL;
2271 }
2272 return code_begin() + cont_offset;
2273 }
2274
2275
2276
2277 void nmethod_init() {
2278 // make sure you didn't forget to adjust the filler fields
2279 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2280 }
2281
2282
2283 //-------------------------------------------------------------------------------------------
2284
2285
2286 // QQQ might we make this work from a frame??
2287 nmethodLocker::nmethodLocker(address pc) {
2288 CodeBlob* cb = CodeCache::find_blob(pc);
2289 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2290 _nm = (nmethod*)cb;
2291 lock_nmethod(_nm);
2292 }
2293
2294 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2295 // should pass zombie_ok == true.
2296 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2297 if (nm == NULL) return;
2298 Atomic::inc(&nm->_lock_count);
2299 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2300 }
2301
2302 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2303 if (nm == NULL) return;
2304 Atomic::dec(&nm->_lock_count);
2305 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2306 }
2307
2308
2309 // -----------------------------------------------------------------------------
2310 // nmethod::get_deopt_original_pc
2311 //
2312 // Return the original PC for the given PC if:
2313 // (a) the given PC belongs to a nmethod and
2314 // (b) it is a deopt PC
2315 address nmethod::get_deopt_original_pc(const frame* fr) {
2316 if (fr->cb() == NULL) return NULL;
2317
2318 nmethod* nm = fr->cb()->as_nmethod_or_null();
2319 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2320 return nm->get_original_pc(fr);
2321
2322 return NULL;
2323 }
2324
2325
2326 // -----------------------------------------------------------------------------
2327 // MethodHandle
2328
2329 bool nmethod::is_method_handle_return(address return_pc) {
2330 if (!has_method_handle_invokes()) return false;
2331 PcDesc* pd = pc_desc_at(return_pc);
2332 if (pd == NULL)
2333 return false;
2334 return pd->is_method_handle_invoke();
2335 }
2336
2337
2338 // -----------------------------------------------------------------------------
2339 // Verification
2340
2341 class VerifyOopsClosure: public OopClosure {
2342 nmethod* _nm;
2343 bool _ok;
2344 public:
2345 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2346 bool ok() { return _ok; }
2347 virtual void do_oop(oop* p) {
2348 if ((*p) == NULL || (*p)->is_oop()) return;
2349 if (_ok) {
2350 _nm->print_nmethod(true);
2351 _ok = false;
2352 }
2353 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2354 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2355 }
2356 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2357 };
2358
2359 void nmethod::verify() {
2360
2361 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2362 // seems odd.
2363
2364 if( is_zombie() || is_not_entrant() )
2365 return;
2366
2367 // Make sure all the entry points are correctly aligned for patching.
2368 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2369
2370 // assert(method()->is_oop(), "must be valid");
2371
2372 ResourceMark rm;
2373
2374 if (!CodeCache::contains(this)) {
2375 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2376 }
2377
2378 if(is_native_method() )
2379 return;
2380
2381 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2382 if (nm != this) {
2383 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2384 this));
2385 }
2386
2387 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2388 if (! p->verify(this)) {
2389 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2390 }
2391 }
2392
2393 VerifyOopsClosure voc(this);
2394 oops_do(&voc);
2395 assert(voc.ok(), "embedded oops must be OK");
2396 verify_scavenge_root_oops();
2397
2398 verify_scopes();
2399 }
2400
2401
2402 void nmethod::verify_interrupt_point(address call_site) {
2403 // This code does not work in release mode since
2404 // owns_lock only is available in debug mode.
2405 CompiledIC* ic = NULL;
2406 Thread *cur = Thread::current();
2407 if (CompiledIC_lock->owner() == cur ||
2408 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2409 SafepointSynchronize::is_at_safepoint())) {
2410 ic = CompiledIC_at(this, call_site);
2411 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2412 } else {
2413 MutexLocker ml_verify (CompiledIC_lock);
2414 ic = CompiledIC_at(this, call_site);
2415 }
2416 PcDesc* pd = pc_desc_at(ic->end_of_call());
2417 assert(pd != NULL, "PcDesc must exist");
2418 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2419 pd->obj_decode_offset(), pd->should_reexecute(),
2420 pd->return_oop());
2421 !sd->is_top(); sd = sd->sender()) {
2422 sd->verify();
2423 }
2424 }
2425
2426 void nmethod::verify_scopes() {
2427 if( !method() ) return; // Runtime stubs have no scope
2428 if (method()->is_native()) return; // Ignore stub methods.
2429 // iterate through all interrupt point
2430 // and verify the debug information is valid.
2431 RelocIterator iter((nmethod*)this);
2432 while (iter.next()) {
2433 address stub = NULL;
2434 switch (iter.type()) {
2435 case relocInfo::virtual_call_type:
2436 verify_interrupt_point(iter.addr());
2437 break;
2438 case relocInfo::opt_virtual_call_type:
2439 stub = iter.opt_virtual_call_reloc()->static_stub();
2440 verify_interrupt_point(iter.addr());
2441 break;
2442 case relocInfo::static_call_type:
2443 stub = iter.static_call_reloc()->static_stub();
2444 //verify_interrupt_point(iter.addr());
2445 break;
2446 case relocInfo::runtime_call_type:
2447 address destination = iter.reloc()->value();
2448 // Right now there is no way to find out which entries support
2449 // an interrupt point. It would be nice if we had this
2450 // information in a table.
2451 break;
2452 }
2453 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2454 }
2455 }
2456
2457
2458 // -----------------------------------------------------------------------------
2459 // Non-product code
2460 #ifndef PRODUCT
2461
2462 class DebugScavengeRoot: public OopClosure {
2463 nmethod* _nm;
2464 bool _ok;
2465 public:
2466 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2467 bool ok() { return _ok; }
2468 virtual void do_oop(oop* p) {
2469 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2470 if (_ok) {
2471 _nm->print_nmethod(true);
2472 _ok = false;
2473 }
2474 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2475 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2476 (*p)->print();
2477 }
2478 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2479 };
2480
2481 void nmethod::verify_scavenge_root_oops() {
2482 if (!on_scavenge_root_list()) {
2483 // Actually look inside, to verify the claim that it's clean.
2484 DebugScavengeRoot debug_scavenge_root(this);
2485 oops_do(&debug_scavenge_root);
2486 if (!debug_scavenge_root.ok())
2487 fatal("found an unadvertised bad scavengable oop in the code cache");
2488 }
2489 assert(scavenge_root_not_marked(), "");
2490 }
2491
2492 #endif // PRODUCT
2493
2494 // Printing operations
2495
2496 void nmethod::print() const {
2497 ResourceMark rm;
2498 ttyLocker ttyl; // keep the following output all in one block
2499
2500 tty->print("Compiled method ");
2501
2502 if (is_compiled_by_c1()) {
2503 tty->print("(c1) ");
2504 } else if (is_compiled_by_c2()) {
2505 tty->print("(c2) ");
2506 } else if (is_compiled_by_shark()) {
2507 tty->print("(shark) ");
2508 } else {
2509 tty->print("(nm) ");
2510 }
2511
2512 print_on(tty, NULL);
2513
2514 if (WizardMode) {
2515 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2516 tty->print(" for method " INTPTR_FORMAT , (address)method());
2517 tty->print(" { ");
2518 if (is_in_use()) tty->print("in_use ");
2519 if (is_not_entrant()) tty->print("not_entrant ");
2520 if (is_zombie()) tty->print("zombie ");
2521 if (is_unloaded()) tty->print("unloaded ");
2522 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2523 tty->print_cr("}:");
2524 }
2525 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2526 (address)this,
2527 (address)this + size(),
2528 size());
2529 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2530 relocation_begin(),
2531 relocation_end(),
2532 relocation_size());
2533 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2534 consts_begin(),
2535 consts_end(),
2536 consts_size());
2537 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2538 insts_begin(),
2539 insts_end(),
2540 insts_size());
2541 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2542 stub_begin(),
2543 stub_end(),
2544 stub_size());
2545 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2546 oops_begin(),
2547 oops_end(),
2548 oops_size());
2549 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2550 metadata_begin(),
2551 metadata_end(),
2552 metadata_size());
2553 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2554 scopes_data_begin(),
2555 scopes_data_end(),
2556 scopes_data_size());
2557 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2558 scopes_pcs_begin(),
2559 scopes_pcs_end(),
2560 scopes_pcs_size());
2561 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2562 dependencies_begin(),
2563 dependencies_end(),
2564 dependencies_size());
2565 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2566 handler_table_begin(),
2567 handler_table_end(),
2568 handler_table_size());
2569 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2570 nul_chk_table_begin(),
2571 nul_chk_table_end(),
2572 nul_chk_table_size());
2573 }
2574
2575 void nmethod::print_code() {
2576 HandleMark hm;
2577 ResourceMark m;
2578 Disassembler::decode(this);
2579 }
2580
2581
2582 #ifndef PRODUCT
2583
2584 void nmethod::print_scopes() {
2585 // Find the first pc desc for all scopes in the code and print it.
2586 ResourceMark rm;
2587 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2588 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2589 continue;
2590
2591 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2592 sd->print_on(tty, p);
2593 }
2594 }
2595
2596 void nmethod::print_dependencies() {
2597 ResourceMark rm;
2598 ttyLocker ttyl; // keep the following output all in one block
2599 tty->print_cr("Dependencies:");
2600 for (Dependencies::DepStream deps(this); deps.next(); ) {
2601 deps.print_dependency();
2602 Klass* ctxk = deps.context_type();
2603 if (ctxk != NULL) {
2604 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2605 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2606 }
2607 }
2608 deps.log_dependency(); // put it into the xml log also
2609 }
2610 }
2611
2612
2613 void nmethod::print_relocations() {
2614 ResourceMark m; // in case methods get printed via the debugger
2615 tty->print_cr("relocations:");
2616 RelocIterator iter(this);
2617 iter.print();
2618 if (UseRelocIndex) {
2619 jint* index_end = (jint*)relocation_end() - 1;
2620 jint index_size = *index_end;
2621 jint* index_start = (jint*)( (address)index_end - index_size );
2622 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2623 if (index_size > 0) {
2624 jint* ip;
2625 for (ip = index_start; ip+2 <= index_end; ip += 2)
2626 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2627 ip[0],
2628 ip[1],
2629 header_end()+ip[0],
2630 relocation_begin()-1+ip[1]);
2631 for (; ip < index_end; ip++)
2632 tty->print_cr(" (%d ?)", ip[0]);
2633 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip);
2634 ip++;
2635 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2636 }
2637 }
2638 }
2639
2640
2641 void nmethod::print_pcs() {
2642 ResourceMark m; // in case methods get printed via debugger
2643 tty->print_cr("pc-bytecode offsets:");
2644 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2645 p->print(this);
2646 }
2647 }
2648
2649 #endif // PRODUCT
2650
2651 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2652 RelocIterator iter(this, begin, end);
2653 bool have_one = false;
2654 while (iter.next()) {
2655 have_one = true;
2656 switch (iter.type()) {
2657 case relocInfo::none: return "no_reloc";
2658 case relocInfo::oop_type: {
2659 stringStream st;
2660 oop_Relocation* r = iter.oop_reloc();
2661 oop obj = r->oop_value();
2662 st.print("oop(");
2663 if (obj == NULL) st.print("NULL");
2664 else obj->print_value_on(&st);
2665 st.print(")");
2666 return st.as_string();
2667 }
2668 case relocInfo::metadata_type: {
2669 stringStream st;
2670 metadata_Relocation* r = iter.metadata_reloc();
2671 Metadata* obj = r->metadata_value();
2672 st.print("metadata(");
2673 if (obj == NULL) st.print("NULL");
2674 else obj->print_value_on(&st);
2675 st.print(")");
2676 return st.as_string();
2677 }
2678 case relocInfo::virtual_call_type: return "virtual_call";
2679 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2680 case relocInfo::static_call_type: return "static_call";
2681 case relocInfo::static_stub_type: return "static_stub";
2682 case relocInfo::runtime_call_type: return "runtime_call";
2683 case relocInfo::external_word_type: return "external_word";
2684 case relocInfo::internal_word_type: return "internal_word";
2685 case relocInfo::section_word_type: return "section_word";
2686 case relocInfo::poll_type: return "poll";
2687 case relocInfo::poll_return_type: return "poll_return";
2688 case relocInfo::type_mask: return "type_bit_mask";
2689 }
2690 }
2691 return have_one ? "other" : NULL;
2692 }
2693
2694 // Return a the last scope in (begin..end]
2695 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2696 PcDesc* p = pc_desc_near(begin+1);
2697 if (p != NULL && p->real_pc(this) <= end) {
2698 return new ScopeDesc(this, p->scope_decode_offset(),
2699 p->obj_decode_offset(), p->should_reexecute(),
2700 p->return_oop());
2701 }
2702 return NULL;
2703 }
2704
2705 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2706 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2707 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2708 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2709 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2710 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2711
2712 if (has_method_handle_invokes())
2713 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
2714
2715 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
2716
2717 if (block_begin == entry_point()) {
2718 methodHandle m = method();
2719 if (m.not_null()) {
2720 stream->print(" # ");
2721 m->print_value_on(stream);
2722 stream->cr();
2723 }
2724 if (m.not_null() && !is_osr_method()) {
2725 ResourceMark rm;
2726 int sizeargs = m->size_of_parameters();
2727 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2728 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2729 {
2730 int sig_index = 0;
2731 if (!m->is_static())
2732 sig_bt[sig_index++] = T_OBJECT; // 'this'
2733 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2734 BasicType t = ss.type();
2735 sig_bt[sig_index++] = t;
2736 if (type2size[t] == 2) {
2737 sig_bt[sig_index++] = T_VOID;
2738 } else {
2739 assert(type2size[t] == 1, "size is 1 or 2");
2740 }
2741 }
2742 assert(sig_index == sizeargs, "");
2743 }
2744 const char* spname = "sp"; // make arch-specific?
2745 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2746 int stack_slot_offset = this->frame_size() * wordSize;
2747 int tab1 = 14, tab2 = 24;
2748 int sig_index = 0;
2749 int arg_index = (m->is_static() ? 0 : -1);
2750 bool did_old_sp = false;
2751 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2752 bool at_this = (arg_index == -1);
2753 bool at_old_sp = false;
2754 BasicType t = (at_this ? T_OBJECT : ss.type());
2755 assert(t == sig_bt[sig_index], "sigs in sync");
2756 if (at_this)
2757 stream->print(" # this: ");
2758 else
2759 stream->print(" # parm%d: ", arg_index);
2760 stream->move_to(tab1);
2761 VMReg fst = regs[sig_index].first();
2762 VMReg snd = regs[sig_index].second();
2763 if (fst->is_reg()) {
2764 stream->print("%s", fst->name());
2765 if (snd->is_valid()) {
2766 stream->print(":%s", snd->name());
2767 }
2768 } else if (fst->is_stack()) {
2769 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2770 if (offset == stack_slot_offset) at_old_sp = true;
2771 stream->print("[%s+0x%x]", spname, offset);
2772 } else {
2773 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2774 }
2775 stream->print(" ");
2776 stream->move_to(tab2);
2777 stream->print("= ");
2778 if (at_this) {
2779 m->method_holder()->print_value_on(stream);
2780 } else {
2781 bool did_name = false;
2782 if (!at_this && ss.is_object()) {
2783 Symbol* name = ss.as_symbol_or_null();
2784 if (name != NULL) {
2785 name->print_value_on(stream);
2786 did_name = true;
2787 }
2788 }
2789 if (!did_name)
2790 stream->print("%s", type2name(t));
2791 }
2792 if (at_old_sp) {
2793 stream->print(" (%s of caller)", spname);
2794 did_old_sp = true;
2795 }
2796 stream->cr();
2797 sig_index += type2size[t];
2798 arg_index += 1;
2799 if (!at_this) ss.next();
2800 }
2801 if (!did_old_sp) {
2802 stream->print(" # ");
2803 stream->move_to(tab1);
2804 stream->print("[%s+0x%x]", spname, stack_slot_offset);
2805 stream->print(" (%s of caller)", spname);
2806 stream->cr();
2807 }
2808 }
2809 }
2810 }
2811
2812 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2813 // First, find an oopmap in (begin, end].
2814 // We use the odd half-closed interval so that oop maps and scope descs
2815 // which are tied to the byte after a call are printed with the call itself.
2816 address base = code_begin();
2817 OopMapSet* oms = oop_maps();
2818 if (oms != NULL) {
2819 for (int i = 0, imax = oms->size(); i < imax; i++) {
2820 OopMap* om = oms->at(i);
2821 address pc = base + om->offset();
2822 if (pc > begin) {
2823 if (pc <= end) {
2824 st->move_to(column);
2825 st->print("; ");
2826 om->print_on(st);
2827 }
2828 break;
2829 }
2830 }
2831 }
2832
2833 // Print any debug info present at this pc.
2834 ScopeDesc* sd = scope_desc_in(begin, end);
2835 if (sd != NULL) {
2836 st->move_to(column);
2837 if (sd->bci() == SynchronizationEntryBCI) {
2838 st->print(";*synchronization entry");
2839 } else {
2840 if (sd->method() == NULL) {
2841 st->print("method is NULL");
2842 } else if (sd->method()->is_native()) {
2843 st->print("method is native");
2844 } else {
2845 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2846 st->print(";*%s", Bytecodes::name(bc));
2847 switch (bc) {
2848 case Bytecodes::_invokevirtual:
2849 case Bytecodes::_invokespecial:
2850 case Bytecodes::_invokestatic:
2851 case Bytecodes::_invokeinterface:
2852 {
2853 Bytecode_invoke invoke(sd->method(), sd->bci());
2854 st->print(" ");
2855 if (invoke.name() != NULL)
2856 invoke.name()->print_symbol_on(st);
2857 else
2858 st->print("<UNKNOWN>");
2859 break;
2860 }
2861 case Bytecodes::_getfield:
2862 case Bytecodes::_putfield:
2863 case Bytecodes::_getstatic:
2864 case Bytecodes::_putstatic:
2865 {
2866 Bytecode_field field(sd->method(), sd->bci());
2867 st->print(" ");
2868 if (field.name() != NULL)
2869 field.name()->print_symbol_on(st);
2870 else
2871 st->print("<UNKNOWN>");
2872 }
2873 }
2874 }
2875 }
2876
2877 // Print all scopes
2878 for (;sd != NULL; sd = sd->sender()) {
2879 st->move_to(column);
2880 st->print("; -");
2881 if (sd->method() == NULL) {
2882 st->print("method is NULL");
2883 } else {
2884 sd->method()->print_short_name(st);
2885 }
2886 int lineno = sd->method()->line_number_from_bci(sd->bci());
2887 if (lineno != -1) {
2888 st->print("@%d (line %d)", sd->bci(), lineno);
2889 } else {
2890 st->print("@%d", sd->bci());
2891 }
2892 st->cr();
2893 }
2894 }
2895
2896 // Print relocation information
2897 const char* str = reloc_string_for(begin, end);
2898 if (str != NULL) {
2899 if (sd != NULL) st->cr();
2900 st->move_to(column);
2901 st->print("; {%s}", str);
2902 }
2903 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2904 if (cont_offset != 0) {
2905 st->move_to(column);
2906 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
2907 }
2908
2909 }
2910
2911 #ifndef PRODUCT
2912
2913 void nmethod::print_value_on(outputStream* st) const {
2914 st->print("nmethod");
2915 print_on(st, NULL);
2916 }
2917
2918 void nmethod::print_calls(outputStream* st) {
2919 RelocIterator iter(this);
2920 while (iter.next()) {
2921 switch (iter.type()) {
2922 case relocInfo::virtual_call_type:
2923 case relocInfo::opt_virtual_call_type: {
2924 VerifyMutexLocker mc(CompiledIC_lock);
2925 CompiledIC_at(iter.reloc())->print();
2926 break;
2927 }
2928 case relocInfo::static_call_type:
2929 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2930 compiledStaticCall_at(iter.reloc())->print();
2931 break;
2932 }
2933 }
2934 }
2935
2936 void nmethod::print_handler_table() {
2937 ExceptionHandlerTable(this).print();
2938 }
2939
2940 void nmethod::print_nul_chk_table() {
2941 ImplicitExceptionTable(this).print(code_begin());
2942 }
2943
2944 void nmethod::print_statistics() {
2945 ttyLocker ttyl;
2946 if (xtty != NULL) xtty->head("statistics type='nmethod'");
2947 nmethod_stats.print_native_nmethod_stats();
2948 nmethod_stats.print_nmethod_stats();
2949 DebugInformationRecorder::print_statistics();
2950 nmethod_stats.print_pc_stats();
2951 Dependencies::print_statistics();
2952 if (xtty != NULL) xtty->tail("statistics");
2953 }
2954
2955 #endif // PRODUCT