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) return false;
97 // method() == NULL can happen during debug printing or if the nmethod is zombie
98 assert(method() == NULL || !is_native_method(), "native methods have no compiler");
99 return compiler()->is_c1();
100 }
101 bool nmethod::is_compiled_by_c2() const {
102 if (compiler() == NULL) return false;
103 // method() == NULL can happen during debug printing or if the nmethod is zombie
104 assert(method() == NULL || !is_native_method(), "native methods have no compiler");
105 return compiler()->is_c2();
106 }
107 bool nmethod::is_compiled_by_shark() const {
108 if (compiler() == NULL) return false;
109 // method() == NULL can happen during debug printing or if the nmethod is zombie
110 assert(method() == NULL || !is_native_method(), "native methods have no compiler");
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 }
694 debug_only(verify_scavenge_root_oops());
695 CodeCache::commit(this);
696 }
697
698 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
699 ttyLocker ttyl; // keep the following output all in one block
700 // This output goes directly to the tty, not the compiler log.
701 // To enable tools to match it up with the compilation activity,
702 // be sure to tag this tty output with the compile ID.
703 if (xtty != NULL) {
704 xtty->begin_head("print_native_nmethod");
705 xtty->method(_method);
706 xtty->stamp();
707 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
708 }
709 // print the header part first
710 print();
711 // then print the requested information
712 if (PrintNativeNMethods) {
713 print_code();
714 if (oop_maps != NULL) {
715 oop_maps->print();
716 }
717 }
718 if (PrintRelocations) {
719 print_relocations();
720 }
721 if (xtty != NULL) {
722 xtty->tail("print_native_nmethod");
723 }
724 }
725 }
726
727 // For dtrace wrappers
728 #ifdef HAVE_DTRACE_H
729 nmethod::nmethod(
730 Method* method,
731 int nmethod_size,
732 CodeOffsets* offsets,
733 CodeBuffer* code_buffer,
734 int frame_size)
735 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
736 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
737 _native_receiver_sp_offset(in_ByteSize(-1)),
738 _native_basic_lock_sp_offset(in_ByteSize(-1))
739 {
740 {
741 debug_only(No_Safepoint_Verifier nsv;)
742 assert_locked_or_safepoint(CodeCache_lock);
743
744 init_defaults();
745 _method = method;
746 _entry_bci = InvocationEntryBci;
747 // We have no exception handler or deopt handler make the
748 // values something that will never match a pc like the nmethod vtable entry
749 _exception_offset = 0;
750 _deoptimize_offset = 0;
751 _deoptimize_mh_offset = 0;
752 _unwind_handler_offset = -1;
753 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
754 _orig_pc_offset = 0;
755 _consts_offset = data_offset();
756 _stub_offset = data_offset();
757 _oops_offset = data_offset();
758 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
759 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
760 _scopes_pcs_offset = _scopes_data_offset;
761 _dependencies_offset = _scopes_pcs_offset;
762 _handler_table_offset = _dependencies_offset;
763 _nul_chk_table_offset = _handler_table_offset;
764 _nmethod_end_offset = _nul_chk_table_offset;
765 _compile_id = 0; // default
766 _comp_level = CompLevel_none;
767 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
768 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
769 _osr_entry_point = NULL;
770 _exception_cache = NULL;
771 _pc_desc_cache.reset_to(NULL);
772
773 code_buffer->copy_values_to(this);
774 debug_only(verify_scavenge_root_oops());
775 CodeCache::commit(this);
776 }
777
778 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
779 ttyLocker ttyl; // keep the following output all in one block
780 // This output goes directly to the tty, not the compiler log.
781 // To enable tools to match it up with the compilation activity,
782 // be sure to tag this tty output with the compile ID.
783 if (xtty != NULL) {
784 xtty->begin_head("print_dtrace_nmethod");
785 xtty->method(_method);
786 xtty->stamp();
787 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
788 }
789 // print the header part first
790 print();
791 // then print the requested information
792 if (PrintNMethods) {
793 print_code();
794 }
795 if (PrintRelocations) {
796 print_relocations();
797 }
798 if (xtty != NULL) {
799 xtty->tail("print_dtrace_nmethod");
800 }
801 }
802 }
803 #endif // def HAVE_DTRACE_H
804
805 void* nmethod::operator new(size_t size, int nmethod_size) throw () {
806 // Not critical, may return null if there is too little continuous memory
807 return CodeCache::allocate(nmethod_size);
808 }
809
810 nmethod::nmethod(
811 Method* method,
812 int nmethod_size,
813 int compile_id,
814 int entry_bci,
815 CodeOffsets* offsets,
816 int orig_pc_offset,
817 DebugInformationRecorder* debug_info,
818 Dependencies* dependencies,
819 CodeBuffer *code_buffer,
820 int frame_size,
821 OopMapSet* oop_maps,
822 ExceptionHandlerTable* handler_table,
823 ImplicitExceptionTable* nul_chk_table,
824 AbstractCompiler* compiler,
825 int comp_level
826 )
827 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
828 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
829 _native_receiver_sp_offset(in_ByteSize(-1)),
830 _native_basic_lock_sp_offset(in_ByteSize(-1))
831 {
832 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
833 {
834 debug_only(No_Safepoint_Verifier nsv;)
835 assert_locked_or_safepoint(CodeCache_lock);
836
837 init_defaults();
838 _method = method;
839 _entry_bci = entry_bci;
840 _compile_id = compile_id;
841 _comp_level = comp_level;
842 _compiler = compiler;
843 _orig_pc_offset = orig_pc_offset;
844
845 // Section offsets
846 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
847 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
848
849 // Exception handler and deopt handler are in the stub section
850 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
851 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
852 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
853 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
854 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
855 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
856 } else {
857 _deoptimize_mh_offset = -1;
858 }
859 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
860 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
861 } else {
862 _unwind_handler_offset = -1;
863 }
864
865 _oops_offset = data_offset();
866 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
867 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
868
869 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
870 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
871 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
872 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
873 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
874
875 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
876 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
877 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
878 _exception_cache = NULL;
879 _pc_desc_cache.reset_to(scopes_pcs_begin());
880
881 // Copy contents of ScopeDescRecorder to nmethod
882 code_buffer->copy_values_to(this);
883 debug_info->copy_to(this);
884 dependencies->copy_to(this);
885 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
886 CodeCache::add_scavenge_root_nmethod(this);
887 }
888 debug_only(verify_scavenge_root_oops());
889
890 CodeCache::commit(this);
891
892 // Copy contents of ExceptionHandlerTable to nmethod
893 handler_table->copy_to(this);
894 nul_chk_table->copy_to(this);
895
896 // we use the information of entry points to find out if a method is
897 // static or non static
898 assert(compiler->is_c2() ||
899 _method->is_static() == (entry_point() == _verified_entry_point),
900 " entry points must be same for static methods and vice versa");
901 }
902
903 bool printnmethods = PrintNMethods
904 || CompilerOracle::should_print(_method)
905 || CompilerOracle::has_option_string(_method, "PrintNMethods");
906 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
907 print_nmethod(printnmethods);
908 }
909 }
910
911
912 // Print a short set of xml attributes to identify this nmethod. The
913 // output should be embedded in some other element.
914 void nmethod::log_identity(xmlStream* log) const {
915 log->print(" compile_id='%d'", compile_id());
916 const char* nm_kind = compile_kind();
917 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
918 if (compiler() != NULL) {
919 log->print(" compiler='%s'", compiler()->name());
920 }
921 if (TieredCompilation) {
922 log->print(" level='%d'", comp_level());
923 }
924 }
925
926
927 #define LOG_OFFSET(log, name) \
928 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
929 log->print(" " XSTR(name) "_offset='%d'" , \
930 (intptr_t)name##_begin() - (intptr_t)this)
931
932
933 void nmethod::log_new_nmethod() const {
934 if (LogCompilation && xtty != NULL) {
935 ttyLocker ttyl;
936 HandleMark hm;
937 xtty->begin_elem("nmethod");
938 log_identity(xtty);
939 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
940 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
941
942 LOG_OFFSET(xtty, relocation);
943 LOG_OFFSET(xtty, consts);
944 LOG_OFFSET(xtty, insts);
945 LOG_OFFSET(xtty, stub);
946 LOG_OFFSET(xtty, scopes_data);
947 LOG_OFFSET(xtty, scopes_pcs);
948 LOG_OFFSET(xtty, dependencies);
949 LOG_OFFSET(xtty, handler_table);
950 LOG_OFFSET(xtty, nul_chk_table);
951 LOG_OFFSET(xtty, oops);
952
953 xtty->method(method());
954 xtty->stamp();
955 xtty->end_elem();
956 }
957 }
958
959 #undef LOG_OFFSET
960
961
962 // Print out more verbose output usually for a newly created nmethod.
963 void nmethod::print_on(outputStream* st, const char* msg) const {
964 if (st != NULL) {
965 ttyLocker ttyl;
966 if (WizardMode) {
967 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
968 st->print_cr(" (" INTPTR_FORMAT ")", this);
969 } else {
970 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
971 }
972 }
973 }
974
975
976 void nmethod::print_nmethod(bool printmethod) {
977 ttyLocker ttyl; // keep the following output all in one block
978 if (xtty != NULL) {
979 xtty->begin_head("print_nmethod");
980 xtty->stamp();
981 xtty->end_head();
982 }
983 // print the header part first
984 print();
985 // then print the requested information
986 if (printmethod) {
987 print_code();
988 print_pcs();
989 if (oop_maps()) {
990 oop_maps()->print();
991 }
992 }
993 if (PrintDebugInfo) {
994 print_scopes();
995 }
996 if (PrintRelocations) {
997 print_relocations();
998 }
999 if (PrintDependencies) {
1000 print_dependencies();
1001 }
1002 if (PrintExceptionHandlers) {
1003 print_handler_table();
1004 print_nul_chk_table();
1005 }
1006 if (xtty != NULL) {
1007 xtty->tail("print_nmethod");
1008 }
1009 }
1010
1011
1012 // Promote one word from an assembly-time handle to a live embedded oop.
1013 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1014 if (handle == NULL ||
1015 // As a special case, IC oops are initialized to 1 or -1.
1016 handle == (jobject) Universe::non_oop_word()) {
1017 (*dest) = (oop) handle;
1018 } else {
1019 (*dest) = JNIHandles::resolve_non_null(handle);
1020 }
1021 }
1022
1023
1024 // Have to have the same name because it's called by a template
1025 void nmethod::copy_values(GrowableArray<jobject>* array) {
1026 int length = array->length();
1027 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1028 oop* dest = oops_begin();
1029 for (int index = 0 ; index < length; index++) {
1030 initialize_immediate_oop(&dest[index], array->at(index));
1031 }
1032
1033 // Now we can fix up all the oops in the code. We need to do this
1034 // in the code because the assembler uses jobjects as placeholders.
1035 // The code and relocations have already been initialized by the
1036 // CodeBlob constructor, so it is valid even at this early point to
1037 // iterate over relocations and patch the code.
1038 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1039 }
1040
1041 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1042 int length = array->length();
1043 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1044 Metadata** dest = metadata_begin();
1045 for (int index = 0 ; index < length; index++) {
1046 dest[index] = array->at(index);
1047 }
1048 }
1049
1050 bool nmethod::is_at_poll_return(address pc) {
1051 RelocIterator iter(this, pc, pc+1);
1052 while (iter.next()) {
1053 if (iter.type() == relocInfo::poll_return_type)
1054 return true;
1055 }
1056 return false;
1057 }
1058
1059
1060 bool nmethod::is_at_poll_or_poll_return(address pc) {
1061 RelocIterator iter(this, pc, pc+1);
1062 while (iter.next()) {
1063 relocInfo::relocType t = iter.type();
1064 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1065 return true;
1066 }
1067 return false;
1068 }
1069
1070
1071 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1072 // re-patch all oop-bearing instructions, just in case some oops moved
1073 RelocIterator iter(this, begin, end);
1074 while (iter.next()) {
1075 if (iter.type() == relocInfo::oop_type) {
1076 oop_Relocation* reloc = iter.oop_reloc();
1077 if (initialize_immediates && reloc->oop_is_immediate()) {
1078 oop* dest = reloc->oop_addr();
1079 initialize_immediate_oop(dest, (jobject) *dest);
1080 }
1081 // Refresh the oop-related bits of this instruction.
1082 reloc->fix_oop_relocation();
1083 } else if (iter.type() == relocInfo::metadata_type) {
1084 metadata_Relocation* reloc = iter.metadata_reloc();
1085 reloc->fix_metadata_relocation();
1086 }
1087 }
1088 }
1089
1090
1091 void nmethod::verify_oop_relocations() {
1092 // Ensure sure that the code matches the current oop values
1093 RelocIterator iter(this, NULL, NULL);
1094 while (iter.next()) {
1095 if (iter.type() == relocInfo::oop_type) {
1096 oop_Relocation* reloc = iter.oop_reloc();
1097 if (!reloc->oop_is_immediate()) {
1098 reloc->verify_oop_relocation();
1099 }
1100 }
1101 }
1102 }
1103
1104
1105 ScopeDesc* nmethod::scope_desc_at(address pc) {
1106 PcDesc* pd = pc_desc_at(pc);
1107 guarantee(pd != NULL, "scope must be present");
1108 return new ScopeDesc(this, pd->scope_decode_offset(),
1109 pd->obj_decode_offset(), pd->should_reexecute(),
1110 pd->return_oop());
1111 }
1112
1113
1114 void nmethod::clear_inline_caches() {
1115 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1116 if (is_zombie()) {
1117 return;
1118 }
1119
1120 RelocIterator iter(this);
1121 while (iter.next()) {
1122 iter.reloc()->clear_inline_cache();
1123 }
1124 }
1125
1126
1127 void nmethod::cleanup_inline_caches() {
1128
1129 assert_locked_or_safepoint(CompiledIC_lock);
1130
1131 // If the method is not entrant or zombie then a JMP is plastered over the
1132 // first few bytes. If an oop in the old code was there, that oop
1133 // should not get GC'd. Skip the first few bytes of oops on
1134 // not-entrant methods.
1135 address low_boundary = verified_entry_point();
1136 if (!is_in_use()) {
1137 low_boundary += NativeJump::instruction_size;
1138 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1139 // This means that the low_boundary is going to be a little too high.
1140 // This shouldn't matter, since oops of non-entrant methods are never used.
1141 // In fact, why are we bothering to look at oops in a non-entrant method??
1142 }
1143
1144 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1145 ResourceMark rm;
1146 RelocIterator iter(this, low_boundary);
1147 while(iter.next()) {
1148 switch(iter.type()) {
1149 case relocInfo::virtual_call_type:
1150 case relocInfo::opt_virtual_call_type: {
1151 CompiledIC *ic = CompiledIC_at(iter.reloc());
1152 // Ok, to lookup references to zombies here
1153 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1154 if( cb != NULL && cb->is_nmethod() ) {
1155 nmethod* nm = (nmethod*)cb;
1156 // Clean inline caches pointing to both zombie and not_entrant methods
1157 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1158 }
1159 break;
1160 }
1161 case relocInfo::static_call_type: {
1162 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1163 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1164 if( cb != NULL && cb->is_nmethod() ) {
1165 nmethod* nm = (nmethod*)cb;
1166 // Clean inline caches pointing to both zombie and not_entrant methods
1167 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1168 }
1169 break;
1170 }
1171 }
1172 }
1173 }
1174
1175 // This is a private interface with the sweeper.
1176 void nmethod::mark_as_seen_on_stack() {
1177 assert(is_not_entrant(), "must be a non-entrant method");
1178 // Set the traversal mark to ensure that the sweeper does 2
1179 // cleaning passes before moving to zombie.
1180 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1181 }
1182
1183 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1184 // there are no activations on the stack, not in use by the VM,
1185 // and not in use by the ServiceThread)
1186 bool nmethod::can_not_entrant_be_converted() {
1187 assert(is_not_entrant(), "must be a non-entrant method");
1188
1189 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1190 // count can be greater than the stack traversal count before it hits the
1191 // nmethod for the second time.
1192 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1193 !is_locked_by_vm();
1194 }
1195
1196 void nmethod::inc_decompile_count() {
1197 if (!is_compiled_by_c2()) return;
1198 // Could be gated by ProfileTraps, but do not bother...
1199 Method* m = method();
1200 if (m == NULL) return;
1201 MethodData* mdo = m->method_data();
1202 if (mdo == NULL) return;
1203 // There is a benign race here. See comments in methodData.hpp.
1204 mdo->inc_decompile_count();
1205 }
1206
1207 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1208
1209 post_compiled_method_unload();
1210
1211 // Since this nmethod is being unloaded, make sure that dependencies
1212 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1213 // indicate that this work is being done during a GC.
1214 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1215 assert(is_alive != NULL, "Should be non-NULL");
1216 // A non-NULL is_alive closure indicates that this is being called during GC.
1217 flush_dependencies(is_alive);
1218
1219 // Break cycle between nmethod & method
1220 if (TraceClassUnloading && WizardMode) {
1221 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1222 " unloadable], Method*(" INTPTR_FORMAT
1223 "), cause(" INTPTR_FORMAT ")",
1224 this, (address)_method, (address)cause);
1225 if (!Universe::heap()->is_gc_active())
1226 cause->klass()->print();
1227 }
1228 // Unlink the osr method, so we do not look this up again
1229 if (is_osr_method()) {
1230 invalidate_osr_method();
1231 }
1232 // If _method is already NULL the Method* is about to be unloaded,
1233 // so we don't have to break the cycle. Note that it is possible to
1234 // have the Method* live here, in case we unload the nmethod because
1235 // it is pointing to some oop (other than the Method*) being unloaded.
1236 if (_method != NULL) {
1237 // OSR methods point to the Method*, but the Method* does not
1238 // point back!
1239 if (_method->code() == this) {
1240 _method->clear_code(); // Break a cycle
1241 }
1242 _method = NULL; // Clear the method of this dead nmethod
1243 }
1244 // Make the class unloaded - i.e., change state and notify sweeper
1245 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1246 if (is_in_use()) {
1247 // Transitioning directly from live to unloaded -- so
1248 // we need to force a cache clean-up; remember this
1249 // for later on.
1250 CodeCache::set_needs_cache_clean(true);
1251 }
1252 _state = unloaded;
1253
1254 // Log the unloading.
1255 log_state_change();
1256
1257 // The Method* is gone at this point
1258 assert(_method == NULL, "Tautology");
1259
1260 set_osr_link(NULL);
1261 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1262 NMethodSweeper::notify(this);
1263 }
1264
1265 void nmethod::invalidate_osr_method() {
1266 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1267 // Remove from list of active nmethods
1268 if (method() != NULL)
1269 method()->method_holder()->remove_osr_nmethod(this);
1270 // Set entry as invalid
1271 _entry_bci = InvalidOSREntryBci;
1272 }
1273
1274 void nmethod::log_state_change() const {
1275 if (LogCompilation) {
1276 if (xtty != NULL) {
1277 ttyLocker ttyl; // keep the following output all in one block
1278 if (_state == unloaded) {
1279 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1280 os::current_thread_id());
1281 } else {
1282 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1283 os::current_thread_id(),
1284 (_state == zombie ? " zombie='1'" : ""));
1285 }
1286 log_identity(xtty);
1287 xtty->stamp();
1288 xtty->end_elem();
1289 }
1290 }
1291 if (PrintCompilation && _state != unloaded) {
1292 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1293 }
1294 }
1295
1296 // Common functionality for both make_not_entrant and make_zombie
1297 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1298 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1299 assert(!is_zombie(), "should not already be a zombie");
1300
1301 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1302 nmethodLocker nml(this);
1303 methodHandle the_method(method());
1304 No_Safepoint_Verifier nsv;
1305
1306 {
1307 // invalidate osr nmethod before acquiring the patching lock since
1308 // they both acquire leaf locks and we don't want a deadlock.
1309 // This logic is equivalent to the logic below for patching the
1310 // verified entry point of regular methods.
1311 if (is_osr_method()) {
1312 // this effectively makes the osr nmethod not entrant
1313 invalidate_osr_method();
1314 }
1315
1316 // Enter critical section. Does not block for safepoint.
1317 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1318
1319 if (_state == state) {
1320 // another thread already performed this transition so nothing
1321 // to do, but return false to indicate this.
1322 return false;
1323 }
1324
1325 // The caller can be calling the method statically or through an inline
1326 // cache call.
1327 if (!is_osr_method() && !is_not_entrant()) {
1328 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1329 SharedRuntime::get_handle_wrong_method_stub());
1330 }
1331
1332 if (is_in_use()) {
1333 // It's a true state change, so mark the method as decompiled.
1334 // Do it only for transition from alive.
1335 inc_decompile_count();
1336 }
1337
1338 // Change state
1339 _state = state;
1340
1341 // Log the transition once
1342 log_state_change();
1343
1344 // Remove nmethod from method.
1345 // We need to check if both the _code and _from_compiled_code_entry_point
1346 // refer to this nmethod because there is a race in setting these two fields
1347 // in Method* as seen in bugid 4947125.
1348 // If the vep() points to the zombie nmethod, the memory for the nmethod
1349 // could be flushed and the compiler and vtable stubs could still call
1350 // through it.
1351 if (method() != NULL && (method()->code() == this ||
1352 method()->from_compiled_entry() == verified_entry_point())) {
1353 HandleMark hm;
1354 method()->clear_code();
1355 }
1356
1357 if (state == not_entrant) {
1358 mark_as_seen_on_stack();
1359 }
1360
1361 } // leave critical region under Patching_lock
1362
1363 // When the nmethod becomes zombie it is no longer alive so the
1364 // dependencies must be flushed. nmethods in the not_entrant
1365 // state will be flushed later when the transition to zombie
1366 // happens or they get unloaded.
1367 if (state == zombie) {
1368 {
1369 // Flushing dependecies must be done before any possible
1370 // safepoint can sneak in, otherwise the oops used by the
1371 // dependency logic could have become stale.
1372 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1373 flush_dependencies(NULL);
1374 }
1375
1376 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1377 // event and it hasn't already been reported for this nmethod then
1378 // report it now. The event may have been reported earilier if the GC
1379 // marked it for unloading). JvmtiDeferredEventQueue support means
1380 // we no longer go to a safepoint here.
1381 post_compiled_method_unload();
1382
1383 #ifdef ASSERT
1384 // It's no longer safe to access the oops section since zombie
1385 // nmethods aren't scanned for GC.
1386 _oops_are_stale = true;
1387 #endif
1388 _method = NULL; // the Method may be reclaimed by class unloading
1389 // now that the nmethod is in zombie state
1390 } else {
1391 assert(state == not_entrant, "other cases may need to be handled differently");
1392 }
1393
1394 if (TraceCreateZombies) {
1395 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1396 }
1397
1398 // Make sweeper aware that there is a zombie method that needs to be removed
1399 NMethodSweeper::notify(this);
1400
1401 return true;
1402 }
1403
1404 void nmethod::flush() {
1405 // Note that there are no valid oops in the nmethod anymore.
1406 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1407 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1408
1409 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1410 assert_locked_or_safepoint(CodeCache_lock);
1411
1412 // completely deallocate this method
1413 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1414 if (PrintMethodFlushing) {
1415 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1416 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
1417 }
1418
1419 // We need to deallocate any ExceptionCache data.
1420 // Note that we do not need to grab the nmethod lock for this, it
1421 // better be thread safe if we're disposing of it!
1422 ExceptionCache* ec = exception_cache();
1423 set_exception_cache(NULL);
1424 while(ec != NULL) {
1425 ExceptionCache* next = ec->next();
1426 delete ec;
1427 ec = next;
1428 }
1429
1430 if (on_scavenge_root_list()) {
1431 CodeCache::drop_scavenge_root_nmethod(this);
1432 }
1433
1434 if (is_speculatively_disconnected()) {
1435 CodeCache::remove_saved_code(this);
1436 }
1437
1438 #ifdef SHARK
1439 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1440 #endif // SHARK
1441
1442 ((CodeBlob*)(this))->flush();
1443
1444 CodeCache::free(this);
1445 }
1446
1447
1448 //
1449 // Notify all classes this nmethod is dependent on that it is no
1450 // longer dependent. This should only be called in two situations.
1451 // First, when a nmethod transitions to a zombie all dependents need
1452 // to be clear. Since zombification happens at a safepoint there's no
1453 // synchronization issues. The second place is a little more tricky.
1454 // During phase 1 of mark sweep class unloading may happen and as a
1455 // result some nmethods may get unloaded. In this case the flushing
1456 // of dependencies must happen during phase 1 since after GC any
1457 // dependencies in the unloaded nmethod won't be updated, so
1458 // traversing the dependency information in unsafe. In that case this
1459 // function is called with a non-NULL argument and this function only
1460 // notifies instanceKlasses that are reachable
1461
1462 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1463 assert_locked_or_safepoint(CodeCache_lock);
1464 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1465 "is_alive is non-NULL if and only if we are called during GC");
1466 if (!has_flushed_dependencies()) {
1467 set_has_flushed_dependencies();
1468 for (Dependencies::DepStream deps(this); deps.next(); ) {
1469 Klass* klass = deps.context_type();
1470 if (klass == NULL) continue; // ignore things like evol_method
1471
1472 // During GC the is_alive closure is non-NULL, and is used to
1473 // determine liveness of dependees that need to be updated.
1474 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1475 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1476 }
1477 }
1478 }
1479 }
1480
1481
1482 // If this oop is not live, the nmethod can be unloaded.
1483 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1484 assert(root != NULL, "just checking");
1485 oop obj = *root;
1486 if (obj == NULL || is_alive->do_object_b(obj)) {
1487 return false;
1488 }
1489
1490 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1491 // simply because one of its constant oops has gone dead.
1492 // No actual classes need to be unloaded in order for this to occur.
1493 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1494 make_unloaded(is_alive, obj);
1495 return true;
1496 }
1497
1498 // ------------------------------------------------------------------
1499 // post_compiled_method_load_event
1500 // new method for install_code() path
1501 // Transfer information from compilation to jvmti
1502 void nmethod::post_compiled_method_load_event() {
1503
1504 Method* moop = method();
1505 #ifndef USDT2
1506 HS_DTRACE_PROBE8(hotspot, compiled__method__load,
1507 moop->klass_name()->bytes(),
1508 moop->klass_name()->utf8_length(),
1509 moop->name()->bytes(),
1510 moop->name()->utf8_length(),
1511 moop->signature()->bytes(),
1512 moop->signature()->utf8_length(),
1513 insts_begin(), insts_size());
1514 #else /* USDT2 */
1515 HOTSPOT_COMPILED_METHOD_LOAD(
1516 (char *) moop->klass_name()->bytes(),
1517 moop->klass_name()->utf8_length(),
1518 (char *) moop->name()->bytes(),
1519 moop->name()->utf8_length(),
1520 (char *) moop->signature()->bytes(),
1521 moop->signature()->utf8_length(),
1522 insts_begin(), insts_size());
1523 #endif /* USDT2 */
1524
1525 if (JvmtiExport::should_post_compiled_method_load() ||
1526 JvmtiExport::should_post_compiled_method_unload()) {
1527 get_and_cache_jmethod_id();
1528 }
1529
1530 if (JvmtiExport::should_post_compiled_method_load()) {
1531 // Let the Service thread (which is a real Java thread) post the event
1532 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1533 JvmtiDeferredEventQueue::enqueue(
1534 JvmtiDeferredEvent::compiled_method_load_event(this));
1535 }
1536 }
1537
1538 jmethodID nmethod::get_and_cache_jmethod_id() {
1539 if (_jmethod_id == NULL) {
1540 // Cache the jmethod_id since it can no longer be looked up once the
1541 // method itself has been marked for unloading.
1542 _jmethod_id = method()->jmethod_id();
1543 }
1544 return _jmethod_id;
1545 }
1546
1547 void nmethod::post_compiled_method_unload() {
1548 if (unload_reported()) {
1549 // During unloading we transition to unloaded and then to zombie
1550 // and the unloading is reported during the first transition.
1551 return;
1552 }
1553
1554 assert(_method != NULL && !is_unloaded(), "just checking");
1555 DTRACE_METHOD_UNLOAD_PROBE(method());
1556
1557 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1558 // post the event. Sometime later this nmethod will be made a zombie
1559 // by the sweeper but the Method* will not be valid at that point.
1560 // If the _jmethod_id is null then no load event was ever requested
1561 // so don't bother posting the unload. The main reason for this is
1562 // that the jmethodID is a weak reference to the Method* so if
1563 // it's being unloaded there's no way to look it up since the weak
1564 // ref will have been cleared.
1565 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1566 assert(!unload_reported(), "already unloaded");
1567 JvmtiDeferredEvent event =
1568 JvmtiDeferredEvent::compiled_method_unload_event(this,
1569 _jmethod_id, insts_begin());
1570 if (SafepointSynchronize::is_at_safepoint()) {
1571 // Don't want to take the queueing lock. Add it as pending and
1572 // it will get enqueued later.
1573 JvmtiDeferredEventQueue::add_pending_event(event);
1574 } else {
1575 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1576 JvmtiDeferredEventQueue::enqueue(event);
1577 }
1578 }
1579
1580 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1581 // any time. As the nmethod is being unloaded now we mark it has
1582 // having the unload event reported - this will ensure that we don't
1583 // attempt to report the event in the unlikely scenario where the
1584 // event is enabled at the time the nmethod is made a zombie.
1585 set_unload_reported();
1586 }
1587
1588 // This is called at the end of the strong tracing/marking phase of a
1589 // GC to unload an nmethod if it contains otherwise unreachable
1590 // oops.
1591
1592 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1593 // Make sure the oop's ready to receive visitors
1594 assert(!is_zombie() && !is_unloaded(),
1595 "should not call follow on zombie or unloaded nmethod");
1596
1597 // If the method is not entrant then a JMP is plastered over the
1598 // first few bytes. If an oop in the old code was there, that oop
1599 // should not get GC'd. Skip the first few bytes of oops on
1600 // not-entrant methods.
1601 address low_boundary = verified_entry_point();
1602 if (is_not_entrant()) {
1603 low_boundary += NativeJump::instruction_size;
1604 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1605 // (See comment above.)
1606 }
1607
1608 // The RedefineClasses() API can cause the class unloading invariant
1609 // to no longer be true. See jvmtiExport.hpp for details.
1610 // Also, leave a debugging breadcrumb in local flag.
1611 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1612 if (a_class_was_redefined) {
1613 // This set of the unloading_occurred flag is done before the
1614 // call to post_compiled_method_unload() so that the unloading
1615 // of this nmethod is reported.
1616 unloading_occurred = true;
1617 }
1618
1619 // Exception cache
1620 ExceptionCache* ec = exception_cache();
1621 while (ec != NULL) {
1622 Klass* ex_klass = ec->exception_type();
1623 ExceptionCache* next_ec = ec->next();
1624 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
1625 remove_from_exception_cache(ec);
1626 }
1627 ec = next_ec;
1628 }
1629
1630 // If class unloading occurred we first iterate over all inline caches and
1631 // clear ICs where the cached oop is referring to an unloaded klass or method.
1632 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1633 // iteration below.
1634 if (unloading_occurred) {
1635 RelocIterator iter(this, low_boundary);
1636 while(iter.next()) {
1637 if (iter.type() == relocInfo::virtual_call_type) {
1638 CompiledIC *ic = CompiledIC_at(iter.reloc());
1639 if (ic->is_icholder_call()) {
1640 // The only exception is compiledICHolder oops which may
1641 // yet be marked below. (We check this further below).
1642 CompiledICHolder* cichk_oop = ic->cached_icholder();
1643 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1644 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1645 continue;
1646 }
1647 } else {
1648 Metadata* ic_oop = ic->cached_metadata();
1649 if (ic_oop != NULL) {
1650 if (ic_oop->is_klass()) {
1651 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1652 continue;
1653 }
1654 } else if (ic_oop->is_method()) {
1655 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1656 continue;
1657 }
1658 } else {
1659 ShouldNotReachHere();
1660 }
1661 }
1662 }
1663 ic->set_to_clean();
1664 }
1665 }
1666 }
1667
1668 // Compiled code
1669 {
1670 RelocIterator iter(this, low_boundary);
1671 while (iter.next()) {
1672 if (iter.type() == relocInfo::oop_type) {
1673 oop_Relocation* r = iter.oop_reloc();
1674 // In this loop, we must only traverse those oops directly embedded in
1675 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1676 assert(1 == (r->oop_is_immediate()) +
1677 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1678 "oop must be found in exactly one place");
1679 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1680 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1681 return;
1682 }
1683 }
1684 }
1685 }
1686 }
1687
1688
1689 // Scopes
1690 for (oop* p = oops_begin(); p < oops_end(); p++) {
1691 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1692 if (can_unload(is_alive, p, unloading_occurred)) {
1693 return;
1694 }
1695 }
1696
1697 // Ensure that all metadata is still alive
1698 verify_metadata_loaders(low_boundary, is_alive);
1699 }
1700
1701 #ifdef ASSERT
1702
1703 class CheckClass : AllStatic {
1704 static BoolObjectClosure* _is_alive;
1705
1706 // Check class_loader is alive for this bit of metadata.
1707 static void check_class(Metadata* md) {
1708 Klass* klass = NULL;
1709 if (md->is_klass()) {
1710 klass = ((Klass*)md);
1711 } else if (md->is_method()) {
1712 klass = ((Method*)md)->method_holder();
1713 } else if (md->is_methodData()) {
1714 klass = ((MethodData*)md)->method()->method_holder();
1715 } else {
1716 md->print();
1717 ShouldNotReachHere();
1718 }
1719 assert(klass->is_loader_alive(_is_alive), "must be alive");
1720 }
1721 public:
1722 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
1723 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
1724 _is_alive = is_alive;
1725 nm->metadata_do(check_class);
1726 }
1727 };
1728
1729 // This is called during a safepoint so can use static data
1730 BoolObjectClosure* CheckClass::_is_alive = NULL;
1731 #endif // ASSERT
1732
1733
1734 // Processing of oop references should have been sufficient to keep
1735 // all strong references alive. Any weak references should have been
1736 // cleared as well. Visit all the metadata and ensure that it's
1737 // really alive.
1738 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
1739 #ifdef ASSERT
1740 RelocIterator iter(this, low_boundary);
1741 while (iter.next()) {
1742 // static_stub_Relocations may have dangling references to
1743 // Method*s so trim them out here. Otherwise it looks like
1744 // compiled code is maintaining a link to dead metadata.
1745 address static_call_addr = NULL;
1746 if (iter.type() == relocInfo::opt_virtual_call_type) {
1747 CompiledIC* cic = CompiledIC_at(iter.reloc());
1748 if (!cic->is_call_to_interpreted()) {
1749 static_call_addr = iter.addr();
1750 }
1751 } else if (iter.type() == relocInfo::static_call_type) {
1752 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
1753 if (!csc->is_call_to_interpreted()) {
1754 static_call_addr = iter.addr();
1755 }
1756 }
1757 if (static_call_addr != NULL) {
1758 RelocIterator sciter(this, low_boundary);
1759 while (sciter.next()) {
1760 if (sciter.type() == relocInfo::static_stub_type &&
1761 sciter.static_stub_reloc()->static_call() == static_call_addr) {
1762 sciter.static_stub_reloc()->clear_inline_cache();
1763 }
1764 }
1765 }
1766 }
1767 // Check that the metadata embedded in the nmethod is alive
1768 CheckClass::do_check_class(is_alive, this);
1769 #endif
1770 }
1771
1772
1773 // Iterate over metadata calling this function. Used by RedefineClasses
1774 void nmethod::metadata_do(void f(Metadata*)) {
1775 address low_boundary = verified_entry_point();
1776 if (is_not_entrant()) {
1777 low_boundary += NativeJump::instruction_size;
1778 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1779 // (See comment above.)
1780 }
1781 {
1782 // Visit all immediate references that are embedded in the instruction stream.
1783 RelocIterator iter(this, low_boundary);
1784 while (iter.next()) {
1785 if (iter.type() == relocInfo::metadata_type ) {
1786 metadata_Relocation* r = iter.metadata_reloc();
1787 // In this lmetadata, we must only follow those metadatas directly embedded in
1788 // the code. Other metadatas (oop_index>0) are seen as part of
1789 // the metadata section below.
1790 assert(1 == (r->metadata_is_immediate()) +
1791 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1792 "metadata must be found in exactly one place");
1793 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1794 Metadata* md = r->metadata_value();
1795 f(md);
1796 }
1797 } else if (iter.type() == relocInfo::virtual_call_type) {
1798 // Check compiledIC holders associated with this nmethod
1799 CompiledIC *ic = CompiledIC_at(iter.reloc());
1800 if (ic->is_icholder_call()) {
1801 CompiledICHolder* cichk = ic->cached_icholder();
1802 f(cichk->holder_method());
1803 f(cichk->holder_klass());
1804 } else {
1805 Metadata* ic_oop = ic->cached_metadata();
1806 if (ic_oop != NULL) {
1807 f(ic_oop);
1808 }
1809 }
1810 }
1811 }
1812 }
1813
1814 // Visit the metadata section
1815 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1816 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
1817 Metadata* md = *p;
1818 f(md);
1819 }
1820
1821 // Call function Method*, not embedded in these other places.
1822 if (_method != NULL) f(_method);
1823 }
1824
1825
1826 // This method is called twice during GC -- once while
1827 // tracing the "active" nmethods on thread stacks during
1828 // the (strong) marking phase, and then again when walking
1829 // the code cache contents during the weak roots processing
1830 // phase. The two uses are distinguished by means of the
1831 // 'do_strong_roots_only' flag, which is true in the first
1832 // case. We want to walk the weak roots in the nmethod
1833 // only in the second case. The weak roots in the nmethod
1834 // are the oops in the ExceptionCache and the InlineCache
1835 // oops.
1836 void nmethod::oops_do(OopClosure* f, bool do_strong_roots_only) {
1837 // make sure the oops ready to receive visitors
1838 assert(!is_zombie() && !is_unloaded(),
1839 "should not call follow on zombie or unloaded nmethod");
1840
1841 // If the method is not entrant or zombie then a JMP is plastered over the
1842 // first few bytes. If an oop in the old code was there, that oop
1843 // should not get GC'd. Skip the first few bytes of oops on
1844 // not-entrant methods.
1845 address low_boundary = verified_entry_point();
1846 if (is_not_entrant()) {
1847 low_boundary += NativeJump::instruction_size;
1848 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1849 // (See comment above.)
1850 }
1851
1852 RelocIterator iter(this, low_boundary);
1853
1854 while (iter.next()) {
1855 if (iter.type() == relocInfo::oop_type ) {
1856 oop_Relocation* r = iter.oop_reloc();
1857 // In this loop, we must only follow those oops directly embedded in
1858 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1859 assert(1 == (r->oop_is_immediate()) +
1860 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1861 "oop must be found in exactly one place");
1862 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1863 f->do_oop(r->oop_addr());
1864 }
1865 }
1866 }
1867
1868 // Scopes
1869 // This includes oop constants not inlined in the code stream.
1870 for (oop* p = oops_begin(); p < oops_end(); p++) {
1871 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1872 f->do_oop(p);
1873 }
1874 }
1875
1876 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1877
1878 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1879
1880 // An nmethod is "marked" if its _mark_link is set non-null.
1881 // Even if it is the end of the linked list, it will have a non-null link value,
1882 // as long as it is on the list.
1883 // This code must be MP safe, because it is used from parallel GC passes.
1884 bool nmethod::test_set_oops_do_mark() {
1885 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1886 nmethod* observed_mark_link = _oops_do_mark_link;
1887 if (observed_mark_link == NULL) {
1888 // Claim this nmethod for this thread to mark.
1889 observed_mark_link = (nmethod*)
1890 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1891 if (observed_mark_link == NULL) {
1892
1893 // Atomically append this nmethod (now claimed) to the head of the list:
1894 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1895 for (;;) {
1896 nmethod* required_mark_nmethods = observed_mark_nmethods;
1897 _oops_do_mark_link = required_mark_nmethods;
1898 observed_mark_nmethods = (nmethod*)
1899 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1900 if (observed_mark_nmethods == required_mark_nmethods)
1901 break;
1902 }
1903 // Mark was clear when we first saw this guy.
1904 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
1905 return false;
1906 }
1907 }
1908 // On fall through, another racing thread marked this nmethod before we did.
1909 return true;
1910 }
1911
1912 void nmethod::oops_do_marking_prologue() {
1913 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
1914 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1915 // We use cmpxchg_ptr instead of regular assignment here because the user
1916 // may fork a bunch of threads, and we need them all to see the same state.
1917 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1918 guarantee(observed == NULL, "no races in this sequential code");
1919 }
1920
1921 void nmethod::oops_do_marking_epilogue() {
1922 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1923 nmethod* cur = _oops_do_mark_nmethods;
1924 while (cur != NMETHOD_SENTINEL) {
1925 assert(cur != NULL, "not NULL-terminated");
1926 nmethod* next = cur->_oops_do_mark_link;
1927 cur->_oops_do_mark_link = NULL;
1928 cur->fix_oop_relocations();
1929 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
1930 cur = next;
1931 }
1932 void* required = _oops_do_mark_nmethods;
1933 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1934 guarantee(observed == required, "no races in this sequential code");
1935 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
1936 }
1937
1938 class DetectScavengeRoot: public OopClosure {
1939 bool _detected_scavenge_root;
1940 public:
1941 DetectScavengeRoot() : _detected_scavenge_root(false)
1942 { NOT_PRODUCT(_print_nm = NULL); }
1943 bool detected_scavenge_root() { return _detected_scavenge_root; }
1944 virtual void do_oop(oop* p) {
1945 if ((*p) != NULL && (*p)->is_scavengable()) {
1946 NOT_PRODUCT(maybe_print(p));
1947 _detected_scavenge_root = true;
1948 }
1949 }
1950 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1951
1952 #ifndef PRODUCT
1953 nmethod* _print_nm;
1954 void maybe_print(oop* p) {
1955 if (_print_nm == NULL) return;
1956 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
1957 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
1958 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
1959 (intptr_t)(*p), (intptr_t)p);
1960 (*p)->print();
1961 }
1962 #endif //PRODUCT
1963 };
1964
1965 bool nmethod::detect_scavenge_root_oops() {
1966 DetectScavengeRoot detect_scavenge_root;
1967 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
1968 oops_do(&detect_scavenge_root);
1969 return detect_scavenge_root.detected_scavenge_root();
1970 }
1971
1972 // Method that knows how to preserve outgoing arguments at call. This method must be
1973 // called with a frame corresponding to a Java invoke
1974 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1975 #ifndef SHARK
1976 if (!method()->is_native()) {
1977 SimpleScopeDesc ssd(this, fr.pc());
1978 Bytecode_invoke call(ssd.method(), ssd.bci());
1979 bool has_receiver = call.has_receiver();
1980 bool has_appendix = call.has_appendix();
1981 Symbol* signature = call.signature();
1982 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
1983 }
1984 #endif // !SHARK
1985 }
1986
1987
1988 oop nmethod::embeddedOop_at(u_char* p) {
1989 RelocIterator iter(this, p, p + 1);
1990 while (iter.next())
1991 if (iter.type() == relocInfo::oop_type) {
1992 return iter.oop_reloc()->oop_value();
1993 }
1994 return NULL;
1995 }
1996
1997
1998 inline bool includes(void* p, void* from, void* to) {
1999 return from <= p && p < to;
2000 }
2001
2002
2003 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2004 assert(count >= 2, "must be sentinel values, at least");
2005
2006 #ifdef ASSERT
2007 // must be sorted and unique; we do a binary search in find_pc_desc()
2008 int prev_offset = pcs[0].pc_offset();
2009 assert(prev_offset == PcDesc::lower_offset_limit,
2010 "must start with a sentinel");
2011 for (int i = 1; i < count; i++) {
2012 int this_offset = pcs[i].pc_offset();
2013 assert(this_offset > prev_offset, "offsets must be sorted");
2014 prev_offset = this_offset;
2015 }
2016 assert(prev_offset == PcDesc::upper_offset_limit,
2017 "must end with a sentinel");
2018 #endif //ASSERT
2019
2020 // Search for MethodHandle invokes and tag the nmethod.
2021 for (int i = 0; i < count; i++) {
2022 if (pcs[i].is_method_handle_invoke()) {
2023 set_has_method_handle_invokes(true);
2024 break;
2025 }
2026 }
2027 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2028
2029 int size = count * sizeof(PcDesc);
2030 assert(scopes_pcs_size() >= size, "oob");
2031 memcpy(scopes_pcs_begin(), pcs, size);
2032
2033 // Adjust the final sentinel downward.
2034 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2035 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2036 last_pc->set_pc_offset(content_size() + 1);
2037 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2038 // Fill any rounding gaps with copies of the last record.
2039 last_pc[1] = last_pc[0];
2040 }
2041 // The following assert could fail if sizeof(PcDesc) is not
2042 // an integral multiple of oopSize (the rounding term).
2043 // If it fails, change the logic to always allocate a multiple
2044 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2045 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2046 }
2047
2048 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2049 assert(scopes_data_size() >= size, "oob");
2050 memcpy(scopes_data_begin(), buffer, size);
2051 }
2052
2053
2054 #ifdef ASSERT
2055 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2056 PcDesc* lower = nm->scopes_pcs_begin();
2057 PcDesc* upper = nm->scopes_pcs_end();
2058 lower += 1; // exclude initial sentinel
2059 PcDesc* res = NULL;
2060 for (PcDesc* p = lower; p < upper; p++) {
2061 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2062 if (match_desc(p, pc_offset, approximate)) {
2063 if (res == NULL)
2064 res = p;
2065 else
2066 res = (PcDesc*) badAddress;
2067 }
2068 }
2069 return res;
2070 }
2071 #endif
2072
2073
2074 // Finds a PcDesc with real-pc equal to "pc"
2075 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2076 address base_address = code_begin();
2077 if ((pc < base_address) ||
2078 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2079 return NULL; // PC is wildly out of range
2080 }
2081 int pc_offset = (int) (pc - base_address);
2082
2083 // Check the PcDesc cache if it contains the desired PcDesc
2084 // (This as an almost 100% hit rate.)
2085 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2086 if (res != NULL) {
2087 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2088 return res;
2089 }
2090
2091 // Fallback algorithm: quasi-linear search for the PcDesc
2092 // Find the last pc_offset less than the given offset.
2093 // The successor must be the required match, if there is a match at all.
2094 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2095 PcDesc* lower = scopes_pcs_begin();
2096 PcDesc* upper = scopes_pcs_end();
2097 upper -= 1; // exclude final sentinel
2098 if (lower >= upper) return NULL; // native method; no PcDescs at all
2099
2100 #define assert_LU_OK \
2101 /* invariant on lower..upper during the following search: */ \
2102 assert(lower->pc_offset() < pc_offset, "sanity"); \
2103 assert(upper->pc_offset() >= pc_offset, "sanity")
2104 assert_LU_OK;
2105
2106 // Use the last successful return as a split point.
2107 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2108 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2109 if (mid->pc_offset() < pc_offset) {
2110 lower = mid;
2111 } else {
2112 upper = mid;
2113 }
2114
2115 // Take giant steps at first (4096, then 256, then 16, then 1)
2116 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2117 const int RADIX = (1 << LOG2_RADIX);
2118 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2119 while ((mid = lower + step) < upper) {
2120 assert_LU_OK;
2121 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2122 if (mid->pc_offset() < pc_offset) {
2123 lower = mid;
2124 } else {
2125 upper = mid;
2126 break;
2127 }
2128 }
2129 assert_LU_OK;
2130 }
2131
2132 // Sneak up on the value with a linear search of length ~16.
2133 while (true) {
2134 assert_LU_OK;
2135 mid = lower + 1;
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 #undef assert_LU_OK
2145
2146 if (match_desc(upper, pc_offset, approximate)) {
2147 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2148 _pc_desc_cache.add_pc_desc(upper);
2149 return upper;
2150 } else {
2151 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2152 return NULL;
2153 }
2154 }
2155
2156
2157 bool nmethod::check_all_dependencies() {
2158 bool found_check = false;
2159 // wholesale check of all dependencies
2160 for (Dependencies::DepStream deps(this); deps.next(); ) {
2161 if (deps.check_dependency() != NULL) {
2162 found_check = true;
2163 NOT_DEBUG(break);
2164 }
2165 }
2166 return found_check; // tell caller if we found anything
2167 }
2168
2169 bool nmethod::check_dependency_on(DepChange& changes) {
2170 // What has happened:
2171 // 1) a new class dependee has been added
2172 // 2) dependee and all its super classes have been marked
2173 bool found_check = false; // set true if we are upset
2174 for (Dependencies::DepStream deps(this); deps.next(); ) {
2175 // Evaluate only relevant dependencies.
2176 if (deps.spot_check_dependency_at(changes) != NULL) {
2177 found_check = true;
2178 NOT_DEBUG(break);
2179 }
2180 }
2181 return found_check;
2182 }
2183
2184 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2185 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2186 Array<Method*>* dependee_methods = dependee_ik->methods();
2187 for (Dependencies::DepStream deps(this); deps.next(); ) {
2188 if (deps.type() == Dependencies::evol_method) {
2189 Method* method = deps.method_argument(0);
2190 for (int j = 0; j < dependee_methods->length(); j++) {
2191 if (dependee_methods->at(j) == method) {
2192 // RC_TRACE macro has an embedded ResourceMark
2193 RC_TRACE(0x01000000,
2194 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2195 _method->method_holder()->external_name(),
2196 _method->name()->as_C_string(),
2197 _method->signature()->as_C_string(), compile_id(),
2198 method->method_holder()->external_name(),
2199 method->name()->as_C_string(),
2200 method->signature()->as_C_string()));
2201 if (TraceDependencies || LogCompilation)
2202 deps.log_dependency(dependee);
2203 return true;
2204 }
2205 }
2206 }
2207 }
2208 return false;
2209 }
2210
2211 // Called from mark_for_deoptimization, when dependee is invalidated.
2212 bool nmethod::is_dependent_on_method(Method* dependee) {
2213 for (Dependencies::DepStream deps(this); deps.next(); ) {
2214 if (deps.type() != Dependencies::evol_method)
2215 continue;
2216 Method* method = deps.method_argument(0);
2217 if (method == dependee) return true;
2218 }
2219 return false;
2220 }
2221
2222
2223 bool nmethod::is_patchable_at(address instr_addr) {
2224 assert(insts_contains(instr_addr), "wrong nmethod used");
2225 if (is_zombie()) {
2226 // a zombie may never be patched
2227 return false;
2228 }
2229 return true;
2230 }
2231
2232
2233 address nmethod::continuation_for_implicit_exception(address pc) {
2234 // Exception happened outside inline-cache check code => we are inside
2235 // an active nmethod => use cpc to determine a return address
2236 int exception_offset = pc - code_begin();
2237 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2238 #ifdef ASSERT
2239 if (cont_offset == 0) {
2240 Thread* thread = ThreadLocalStorage::get_thread_slow();
2241 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2242 HandleMark hm(thread);
2243 ResourceMark rm(thread);
2244 CodeBlob* cb = CodeCache::find_blob(pc);
2245 assert(cb != NULL && cb == this, "");
2246 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2247 print();
2248 method()->print_codes();
2249 print_code();
2250 print_pcs();
2251 }
2252 #endif
2253 if (cont_offset == 0) {
2254 // Let the normal error handling report the exception
2255 return NULL;
2256 }
2257 return code_begin() + cont_offset;
2258 }
2259
2260
2261
2262 void nmethod_init() {
2263 // make sure you didn't forget to adjust the filler fields
2264 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2265 }
2266
2267
2268 //-------------------------------------------------------------------------------------------
2269
2270
2271 // QQQ might we make this work from a frame??
2272 nmethodLocker::nmethodLocker(address pc) {
2273 CodeBlob* cb = CodeCache::find_blob(pc);
2274 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2275 _nm = (nmethod*)cb;
2276 lock_nmethod(_nm);
2277 }
2278
2279 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2280 // should pass zombie_ok == true.
2281 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2282 if (nm == NULL) return;
2283 Atomic::inc(&nm->_lock_count);
2284 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2285 }
2286
2287 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2288 if (nm == NULL) return;
2289 Atomic::dec(&nm->_lock_count);
2290 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2291 }
2292
2293
2294 // -----------------------------------------------------------------------------
2295 // nmethod::get_deopt_original_pc
2296 //
2297 // Return the original PC for the given PC if:
2298 // (a) the given PC belongs to a nmethod and
2299 // (b) it is a deopt PC
2300 address nmethod::get_deopt_original_pc(const frame* fr) {
2301 if (fr->cb() == NULL) return NULL;
2302
2303 nmethod* nm = fr->cb()->as_nmethod_or_null();
2304 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2305 return nm->get_original_pc(fr);
2306
2307 return NULL;
2308 }
2309
2310
2311 // -----------------------------------------------------------------------------
2312 // MethodHandle
2313
2314 bool nmethod::is_method_handle_return(address return_pc) {
2315 if (!has_method_handle_invokes()) return false;
2316 PcDesc* pd = pc_desc_at(return_pc);
2317 if (pd == NULL)
2318 return false;
2319 return pd->is_method_handle_invoke();
2320 }
2321
2322
2323 // -----------------------------------------------------------------------------
2324 // Verification
2325
2326 class VerifyOopsClosure: public OopClosure {
2327 nmethod* _nm;
2328 bool _ok;
2329 public:
2330 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2331 bool ok() { return _ok; }
2332 virtual void do_oop(oop* p) {
2333 if ((*p) == NULL || (*p)->is_oop()) return;
2334 if (_ok) {
2335 _nm->print_nmethod(true);
2336 _ok = false;
2337 }
2338 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2339 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2340 }
2341 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2342 };
2343
2344 void nmethod::verify() {
2345
2346 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2347 // seems odd.
2348
2349 if( is_zombie() || is_not_entrant() )
2350 return;
2351
2352 // Make sure all the entry points are correctly aligned for patching.
2353 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2354
2355 // assert(method()->is_oop(), "must be valid");
2356
2357 ResourceMark rm;
2358
2359 if (!CodeCache::contains(this)) {
2360 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2361 }
2362
2363 if(is_native_method() )
2364 return;
2365
2366 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2367 if (nm != this) {
2368 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2369 this));
2370 }
2371
2372 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2373 if (! p->verify(this)) {
2374 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2375 }
2376 }
2377
2378 VerifyOopsClosure voc(this);
2379 oops_do(&voc);
2380 assert(voc.ok(), "embedded oops must be OK");
2381 verify_scavenge_root_oops();
2382
2383 verify_scopes();
2384 }
2385
2386
2387 void nmethod::verify_interrupt_point(address call_site) {
2388 // This code does not work in release mode since
2389 // owns_lock only is available in debug mode.
2390 CompiledIC* ic = NULL;
2391 Thread *cur = Thread::current();
2392 if (CompiledIC_lock->owner() == cur ||
2393 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2394 SafepointSynchronize::is_at_safepoint())) {
2395 ic = CompiledIC_at(this, call_site);
2396 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2397 } else {
2398 MutexLocker ml_verify (CompiledIC_lock);
2399 ic = CompiledIC_at(this, call_site);
2400 }
2401 PcDesc* pd = pc_desc_at(ic->end_of_call());
2402 assert(pd != NULL, "PcDesc must exist");
2403 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2404 pd->obj_decode_offset(), pd->should_reexecute(),
2405 pd->return_oop());
2406 !sd->is_top(); sd = sd->sender()) {
2407 sd->verify();
2408 }
2409 }
2410
2411 void nmethod::verify_scopes() {
2412 if( !method() ) return; // Runtime stubs have no scope
2413 if (method()->is_native()) return; // Ignore stub methods.
2414 // iterate through all interrupt point
2415 // and verify the debug information is valid.
2416 RelocIterator iter((nmethod*)this);
2417 while (iter.next()) {
2418 address stub = NULL;
2419 switch (iter.type()) {
2420 case relocInfo::virtual_call_type:
2421 verify_interrupt_point(iter.addr());
2422 break;
2423 case relocInfo::opt_virtual_call_type:
2424 stub = iter.opt_virtual_call_reloc()->static_stub();
2425 verify_interrupt_point(iter.addr());
2426 break;
2427 case relocInfo::static_call_type:
2428 stub = iter.static_call_reloc()->static_stub();
2429 //verify_interrupt_point(iter.addr());
2430 break;
2431 case relocInfo::runtime_call_type:
2432 address destination = iter.reloc()->value();
2433 // Right now there is no way to find out which entries support
2434 // an interrupt point. It would be nice if we had this
2435 // information in a table.
2436 break;
2437 }
2438 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2439 }
2440 }
2441
2442
2443 // -----------------------------------------------------------------------------
2444 // Non-product code
2445 #ifndef PRODUCT
2446
2447 class DebugScavengeRoot: public OopClosure {
2448 nmethod* _nm;
2449 bool _ok;
2450 public:
2451 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2452 bool ok() { return _ok; }
2453 virtual void do_oop(oop* p) {
2454 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2455 if (_ok) {
2456 _nm->print_nmethod(true);
2457 _ok = false;
2458 }
2459 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2460 (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2461 (*p)->print();
2462 }
2463 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2464 };
2465
2466 void nmethod::verify_scavenge_root_oops() {
2467 if (!on_scavenge_root_list()) {
2468 // Actually look inside, to verify the claim that it's clean.
2469 DebugScavengeRoot debug_scavenge_root(this);
2470 oops_do(&debug_scavenge_root);
2471 if (!debug_scavenge_root.ok())
2472 fatal("found an unadvertised bad scavengable oop in the code cache");
2473 }
2474 assert(scavenge_root_not_marked(), "");
2475 }
2476
2477 #endif // PRODUCT
2478
2479 // Printing operations
2480
2481 void nmethod::print() const {
2482 ResourceMark rm;
2483 ttyLocker ttyl; // keep the following output all in one block
2484
2485 tty->print("Compiled method ");
2486
2487 if (is_compiled_by_c1()) {
2488 tty->print("(c1) ");
2489 } else if (is_compiled_by_c2()) {
2490 tty->print("(c2) ");
2491 } else if (is_compiled_by_shark()) {
2492 tty->print("(shark) ");
2493 } else {
2494 tty->print("(nm) ");
2495 }
2496
2497 print_on(tty, NULL);
2498
2499 if (WizardMode) {
2500 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2501 tty->print(" for method " INTPTR_FORMAT , (address)method());
2502 tty->print(" { ");
2503 if (is_in_use()) tty->print("in_use ");
2504 if (is_not_entrant()) tty->print("not_entrant ");
2505 if (is_zombie()) tty->print("zombie ");
2506 if (is_unloaded()) tty->print("unloaded ");
2507 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2508 tty->print_cr("}:");
2509 }
2510 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2511 (address)this,
2512 (address)this + size(),
2513 size());
2514 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2515 relocation_begin(),
2516 relocation_end(),
2517 relocation_size());
2518 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2519 consts_begin(),
2520 consts_end(),
2521 consts_size());
2522 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2523 insts_begin(),
2524 insts_end(),
2525 insts_size());
2526 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2527 stub_begin(),
2528 stub_end(),
2529 stub_size());
2530 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2531 oops_begin(),
2532 oops_end(),
2533 oops_size());
2534 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2535 metadata_begin(),
2536 metadata_end(),
2537 metadata_size());
2538 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2539 scopes_data_begin(),
2540 scopes_data_end(),
2541 scopes_data_size());
2542 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2543 scopes_pcs_begin(),
2544 scopes_pcs_end(),
2545 scopes_pcs_size());
2546 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2547 dependencies_begin(),
2548 dependencies_end(),
2549 dependencies_size());
2550 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2551 handler_table_begin(),
2552 handler_table_end(),
2553 handler_table_size());
2554 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2555 nul_chk_table_begin(),
2556 nul_chk_table_end(),
2557 nul_chk_table_size());
2558 }
2559
2560 void nmethod::print_code() {
2561 HandleMark hm;
2562 ResourceMark m;
2563 Disassembler::decode(this);
2564 }
2565
2566
2567 #ifndef PRODUCT
2568
2569 void nmethod::print_scopes() {
2570 // Find the first pc desc for all scopes in the code and print it.
2571 ResourceMark rm;
2572 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2573 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2574 continue;
2575
2576 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2577 sd->print_on(tty, p);
2578 }
2579 }
2580
2581 void nmethod::print_dependencies() {
2582 ResourceMark rm;
2583 ttyLocker ttyl; // keep the following output all in one block
2584 tty->print_cr("Dependencies:");
2585 for (Dependencies::DepStream deps(this); deps.next(); ) {
2586 deps.print_dependency();
2587 Klass* ctxk = deps.context_type();
2588 if (ctxk != NULL) {
2589 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2590 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2591 }
2592 }
2593 deps.log_dependency(); // put it into the xml log also
2594 }
2595 }
2596
2597
2598 void nmethod::print_relocations() {
2599 ResourceMark m; // in case methods get printed via the debugger
2600 tty->print_cr("relocations:");
2601 RelocIterator iter(this);
2602 iter.print();
2603 if (UseRelocIndex) {
2604 jint* index_end = (jint*)relocation_end() - 1;
2605 jint index_size = *index_end;
2606 jint* index_start = (jint*)( (address)index_end - index_size );
2607 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2608 if (index_size > 0) {
2609 jint* ip;
2610 for (ip = index_start; ip+2 <= index_end; ip += 2)
2611 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2612 ip[0],
2613 ip[1],
2614 header_end()+ip[0],
2615 relocation_begin()-1+ip[1]);
2616 for (; ip < index_end; ip++)
2617 tty->print_cr(" (%d ?)", ip[0]);
2618 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip);
2619 ip++;
2620 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2621 }
2622 }
2623 }
2624
2625
2626 void nmethod::print_pcs() {
2627 ResourceMark m; // in case methods get printed via debugger
2628 tty->print_cr("pc-bytecode offsets:");
2629 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2630 p->print(this);
2631 }
2632 }
2633
2634 #endif // PRODUCT
2635
2636 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2637 RelocIterator iter(this, begin, end);
2638 bool have_one = false;
2639 while (iter.next()) {
2640 have_one = true;
2641 switch (iter.type()) {
2642 case relocInfo::none: return "no_reloc";
2643 case relocInfo::oop_type: {
2644 stringStream st;
2645 oop_Relocation* r = iter.oop_reloc();
2646 oop obj = r->oop_value();
2647 st.print("oop(");
2648 if (obj == NULL) st.print("NULL");
2649 else obj->print_value_on(&st);
2650 st.print(")");
2651 return st.as_string();
2652 }
2653 case relocInfo::metadata_type: {
2654 stringStream st;
2655 metadata_Relocation* r = iter.metadata_reloc();
2656 Metadata* obj = r->metadata_value();
2657 st.print("metadata(");
2658 if (obj == NULL) st.print("NULL");
2659 else obj->print_value_on(&st);
2660 st.print(")");
2661 return st.as_string();
2662 }
2663 case relocInfo::virtual_call_type: return "virtual_call";
2664 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2665 case relocInfo::static_call_type: return "static_call";
2666 case relocInfo::static_stub_type: return "static_stub";
2667 case relocInfo::runtime_call_type: return "runtime_call";
2668 case relocInfo::external_word_type: return "external_word";
2669 case relocInfo::internal_word_type: return "internal_word";
2670 case relocInfo::section_word_type: return "section_word";
2671 case relocInfo::poll_type: return "poll";
2672 case relocInfo::poll_return_type: return "poll_return";
2673 case relocInfo::type_mask: return "type_bit_mask";
2674 }
2675 }
2676 return have_one ? "other" : NULL;
2677 }
2678
2679 // Return a the last scope in (begin..end]
2680 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2681 PcDesc* p = pc_desc_near(begin+1);
2682 if (p != NULL && p->real_pc(this) <= end) {
2683 return new ScopeDesc(this, p->scope_decode_offset(),
2684 p->obj_decode_offset(), p->should_reexecute(),
2685 p->return_oop());
2686 }
2687 return NULL;
2688 }
2689
2690 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2691 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2692 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2693 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2694 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2695 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2696
2697 if (has_method_handle_invokes())
2698 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
2699
2700 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
2701
2702 if (block_begin == entry_point()) {
2703 methodHandle m = method();
2704 if (m.not_null()) {
2705 stream->print(" # ");
2706 m->print_value_on(stream);
2707 stream->cr();
2708 }
2709 if (m.not_null() && !is_osr_method()) {
2710 ResourceMark rm;
2711 int sizeargs = m->size_of_parameters();
2712 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2713 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2714 {
2715 int sig_index = 0;
2716 if (!m->is_static())
2717 sig_bt[sig_index++] = T_OBJECT; // 'this'
2718 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2719 BasicType t = ss.type();
2720 sig_bt[sig_index++] = t;
2721 if (type2size[t] == 2) {
2722 sig_bt[sig_index++] = T_VOID;
2723 } else {
2724 assert(type2size[t] == 1, "size is 1 or 2");
2725 }
2726 }
2727 assert(sig_index == sizeargs, "");
2728 }
2729 const char* spname = "sp"; // make arch-specific?
2730 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2731 int stack_slot_offset = this->frame_size() * wordSize;
2732 int tab1 = 14, tab2 = 24;
2733 int sig_index = 0;
2734 int arg_index = (m->is_static() ? 0 : -1);
2735 bool did_old_sp = false;
2736 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2737 bool at_this = (arg_index == -1);
2738 bool at_old_sp = false;
2739 BasicType t = (at_this ? T_OBJECT : ss.type());
2740 assert(t == sig_bt[sig_index], "sigs in sync");
2741 if (at_this)
2742 stream->print(" # this: ");
2743 else
2744 stream->print(" # parm%d: ", arg_index);
2745 stream->move_to(tab1);
2746 VMReg fst = regs[sig_index].first();
2747 VMReg snd = regs[sig_index].second();
2748 if (fst->is_reg()) {
2749 stream->print("%s", fst->name());
2750 if (snd->is_valid()) {
2751 stream->print(":%s", snd->name());
2752 }
2753 } else if (fst->is_stack()) {
2754 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2755 if (offset == stack_slot_offset) at_old_sp = true;
2756 stream->print("[%s+0x%x]", spname, offset);
2757 } else {
2758 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2759 }
2760 stream->print(" ");
2761 stream->move_to(tab2);
2762 stream->print("= ");
2763 if (at_this) {
2764 m->method_holder()->print_value_on(stream);
2765 } else {
2766 bool did_name = false;
2767 if (!at_this && ss.is_object()) {
2768 Symbol* name = ss.as_symbol_or_null();
2769 if (name != NULL) {
2770 name->print_value_on(stream);
2771 did_name = true;
2772 }
2773 }
2774 if (!did_name)
2775 stream->print("%s", type2name(t));
2776 }
2777 if (at_old_sp) {
2778 stream->print(" (%s of caller)", spname);
2779 did_old_sp = true;
2780 }
2781 stream->cr();
2782 sig_index += type2size[t];
2783 arg_index += 1;
2784 if (!at_this) ss.next();
2785 }
2786 if (!did_old_sp) {
2787 stream->print(" # ");
2788 stream->move_to(tab1);
2789 stream->print("[%s+0x%x]", spname, stack_slot_offset);
2790 stream->print(" (%s of caller)", spname);
2791 stream->cr();
2792 }
2793 }
2794 }
2795 }
2796
2797 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2798 // First, find an oopmap in (begin, end].
2799 // We use the odd half-closed interval so that oop maps and scope descs
2800 // which are tied to the byte after a call are printed with the call itself.
2801 address base = code_begin();
2802 OopMapSet* oms = oop_maps();
2803 if (oms != NULL) {
2804 for (int i = 0, imax = oms->size(); i < imax; i++) {
2805 OopMap* om = oms->at(i);
2806 address pc = base + om->offset();
2807 if (pc > begin) {
2808 if (pc <= end) {
2809 st->move_to(column);
2810 st->print("; ");
2811 om->print_on(st);
2812 }
2813 break;
2814 }
2815 }
2816 }
2817
2818 // Print any debug info present at this pc.
2819 ScopeDesc* sd = scope_desc_in(begin, end);
2820 if (sd != NULL) {
2821 st->move_to(column);
2822 if (sd->bci() == SynchronizationEntryBCI) {
2823 st->print(";*synchronization entry");
2824 } else {
2825 if (sd->method() == NULL) {
2826 st->print("method is NULL");
2827 } else if (sd->method()->is_native()) {
2828 st->print("method is native");
2829 } else {
2830 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2831 st->print(";*%s", Bytecodes::name(bc));
2832 switch (bc) {
2833 case Bytecodes::_invokevirtual:
2834 case Bytecodes::_invokespecial:
2835 case Bytecodes::_invokestatic:
2836 case Bytecodes::_invokeinterface:
2837 {
2838 Bytecode_invoke invoke(sd->method(), sd->bci());
2839 st->print(" ");
2840 if (invoke.name() != NULL)
2841 invoke.name()->print_symbol_on(st);
2842 else
2843 st->print("<UNKNOWN>");
2844 break;
2845 }
2846 case Bytecodes::_getfield:
2847 case Bytecodes::_putfield:
2848 case Bytecodes::_getstatic:
2849 case Bytecodes::_putstatic:
2850 {
2851 Bytecode_field field(sd->method(), sd->bci());
2852 st->print(" ");
2853 if (field.name() != NULL)
2854 field.name()->print_symbol_on(st);
2855 else
2856 st->print("<UNKNOWN>");
2857 }
2858 }
2859 }
2860 }
2861
2862 // Print all scopes
2863 for (;sd != NULL; sd = sd->sender()) {
2864 st->move_to(column);
2865 st->print("; -");
2866 if (sd->method() == NULL) {
2867 st->print("method is NULL");
2868 } else {
2869 sd->method()->print_short_name(st);
2870 }
2871 int lineno = sd->method()->line_number_from_bci(sd->bci());
2872 if (lineno != -1) {
2873 st->print("@%d (line %d)", sd->bci(), lineno);
2874 } else {
2875 st->print("@%d", sd->bci());
2876 }
2877 st->cr();
2878 }
2879 }
2880
2881 // Print relocation information
2882 const char* str = reloc_string_for(begin, end);
2883 if (str != NULL) {
2884 if (sd != NULL) st->cr();
2885 st->move_to(column);
2886 st->print("; {%s}", str);
2887 }
2888 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2889 if (cont_offset != 0) {
2890 st->move_to(column);
2891 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
2892 }
2893
2894 }
2895
2896 #ifndef PRODUCT
2897
2898 void nmethod::print_value_on(outputStream* st) const {
2899 st->print("nmethod");
2900 print_on(st, NULL);
2901 }
2902
2903 void nmethod::print_calls(outputStream* st) {
2904 RelocIterator iter(this);
2905 while (iter.next()) {
2906 switch (iter.type()) {
2907 case relocInfo::virtual_call_type:
2908 case relocInfo::opt_virtual_call_type: {
2909 VerifyMutexLocker mc(CompiledIC_lock);
2910 CompiledIC_at(iter.reloc())->print();
2911 break;
2912 }
2913 case relocInfo::static_call_type:
2914 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2915 compiledStaticCall_at(iter.reloc())->print();
2916 break;
2917 }
2918 }
2919 }
2920
2921 void nmethod::print_handler_table() {
2922 ExceptionHandlerTable(this).print();
2923 }
2924
2925 void nmethod::print_nul_chk_table() {
2926 ImplicitExceptionTable(this).print(code_begin());
2927 }
2928
2929 void nmethod::print_statistics() {
2930 ttyLocker ttyl;
2931 if (xtty != NULL) xtty->head("statistics type='nmethod'");
2932 nmethod_stats.print_native_nmethod_stats();
2933 nmethod_stats.print_nmethod_stats();
2934 DebugInformationRecorder::print_statistics();
2935 nmethod_stats.print_pc_stats();
2936 Dependencies::print_statistics();
2937 if (xtty != NULL) xtty->tail("statistics");
2938 }
2939
2940 #endif // PRODUCT