1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "code/codeCache.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/dependencies.hpp"
29 #include "code/nmethod.hpp"
30 #include "code/scopeDesc.hpp"
31 #include "compiler/abstractCompiler.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/compileLog.hpp"
34 #include "compiler/compilerOracle.hpp"
35 #include "compiler/disassembler.hpp"
36 #include "interpreter/bytecode.hpp"
37 #include "oops/methodData.hpp"
38 #include "prims/jvmtiRedefineClassesTrace.hpp"
39 #include "prims/jvmtiImpl.hpp"
40 #include "runtime/sharedRuntime.hpp"
41 #include "runtime/sweeper.hpp"
42 #include "utilities/resourceHash.hpp"
43 #include "utilities/dtrace.hpp"
44 #include "utilities/events.hpp"
45 #include "utilities/xmlstream.hpp"
46 #ifdef SHARK
47 #include "shark/sharkCompiler.hpp"
48 #endif
49
50 #ifdef DTRACE_ENABLED
51
52 // Only bother with this argument setup if dtrace is available
53
54 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
55 { \
56 Method* m = (method); \
57 if (m != NULL) { \
58 Symbol* klass_name = m->klass_name(); \
59 Symbol* name = m->name(); \
60 Symbol* signature = m->signature(); \
61 HOTSPOT_COMPILED_METHOD_UNLOAD( \
62 (char *) klass_name->bytes(), klass_name->utf8_length(), \
63 (char *) name->bytes(), name->utf8_length(), \
64 (char *) signature->bytes(), signature->utf8_length()); \
65 } \
66 }
67
68 #else // ndef DTRACE_ENABLED
69
70 #define DTRACE_METHOD_UNLOAD_PROBE(method)
71
72 #endif
73
74 bool nmethod::is_compiled_by_c1() const {
75 if (compiler() == NULL) {
76 return false;
77 }
78 return compiler()->is_c1();
79 }
80 bool nmethod::is_compiled_by_c2() const {
81 if (compiler() == NULL) {
82 return false;
83 }
84 return compiler()->is_c2();
85 }
86 bool nmethod::is_compiled_by_shark() const {
87 if (compiler() == NULL) {
88 return false;
89 }
90 return compiler()->is_shark();
91 }
92
93
94
95 //---------------------------------------------------------------------------------
96 // NMethod statistics
97 // They are printed under various flags, including:
98 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
99 // (In the latter two cases, they like other stats are printed to the log only.)
100
101 #ifndef PRODUCT
102 // These variables are put into one block to reduce relocations
103 // and make it simpler to print from the debugger.
104 static
105 struct nmethod_stats_struct {
106 int nmethod_count;
107 int total_size;
108 int relocation_size;
109 int consts_size;
110 int insts_size;
111 int stub_size;
112 int scopes_data_size;
113 int scopes_pcs_size;
114 int dependencies_size;
115 int handler_table_size;
116 int nul_chk_table_size;
117 int oops_size;
118
119 void note_nmethod(nmethod* nm) {
120 nmethod_count += 1;
121 total_size += nm->size();
122 relocation_size += nm->relocation_size();
123 consts_size += nm->consts_size();
124 insts_size += nm->insts_size();
125 stub_size += nm->stub_size();
126 oops_size += nm->oops_size();
127 scopes_data_size += nm->scopes_data_size();
128 scopes_pcs_size += nm->scopes_pcs_size();
129 dependencies_size += nm->dependencies_size();
130 handler_table_size += nm->handler_table_size();
131 nul_chk_table_size += nm->nul_chk_table_size();
132 }
133 void print_nmethod_stats() {
134 if (nmethod_count == 0) return;
135 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
136 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
137 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
138 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
139 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size);
140 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
141 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
142 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
143 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
144 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
145 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
146 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
147 }
148
149 int native_nmethod_count;
150 int native_total_size;
151 int native_relocation_size;
152 int native_insts_size;
153 int native_oops_size;
154 void note_native_nmethod(nmethod* nm) {
155 native_nmethod_count += 1;
156 native_total_size += nm->size();
157 native_relocation_size += nm->relocation_size();
158 native_insts_size += nm->insts_size();
159 native_oops_size += nm->oops_size();
160 }
161 void print_native_nmethod_stats() {
162 if (native_nmethod_count == 0) return;
163 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
164 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
165 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
166 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size);
167 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
168 }
169
170 int pc_desc_resets; // number of resets (= number of caches)
171 int pc_desc_queries; // queries to nmethod::find_pc_desc
172 int pc_desc_approx; // number of those which have approximate true
173 int pc_desc_repeats; // number of _pc_descs[0] hits
174 int pc_desc_hits; // number of LRU cache hits
175 int pc_desc_tests; // total number of PcDesc examinations
176 int pc_desc_searches; // total number of quasi-binary search steps
177 int pc_desc_adds; // number of LUR cache insertions
178
179 void print_pc_stats() {
180 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
181 pc_desc_queries,
182 (double)(pc_desc_tests + pc_desc_searches)
183 / pc_desc_queries);
184 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
185 pc_desc_resets,
186 pc_desc_queries, pc_desc_approx,
187 pc_desc_repeats, pc_desc_hits,
188 pc_desc_tests, pc_desc_searches, pc_desc_adds);
189 }
190 } nmethod_stats;
191 #endif //PRODUCT
192
193
194 //---------------------------------------------------------------------------------
195
196
197 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
198 assert(pc != NULL, "Must be non null");
199 assert(exception.not_null(), "Must be non null");
200 assert(handler != NULL, "Must be non null");
201
202 _count = 0;
203 _exception_type = exception->klass();
204 _next = NULL;
205
206 add_address_and_handler(pc,handler);
207 }
208
209
210 address ExceptionCache::match(Handle exception, address pc) {
211 assert(pc != NULL,"Must be non null");
212 assert(exception.not_null(),"Must be non null");
213 if (exception->klass() == exception_type()) {
214 return (test_address(pc));
215 }
216
217 return NULL;
218 }
219
220
221 bool ExceptionCache::match_exception_with_space(Handle exception) {
222 assert(exception.not_null(),"Must be non null");
223 if (exception->klass() == exception_type() && count() < cache_size) {
224 return true;
225 }
226 return false;
227 }
228
229
230 address ExceptionCache::test_address(address addr) {
231 for (int i=0; i<count(); i++) {
232 if (pc_at(i) == addr) {
233 return handler_at(i);
234 }
235 }
236 return NULL;
237 }
238
239
240 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
241 if (test_address(addr) == handler) return true;
242 if (count() < cache_size) {
243 set_pc_at(count(),addr);
244 set_handler_at(count(), handler);
245 increment_count();
246 return true;
247 }
248 return false;
249 }
250
251
252 // private method for handling exception cache
253 // These methods are private, and used to manipulate the exception cache
254 // directly.
255 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
256 ExceptionCache* ec = exception_cache();
257 while (ec != NULL) {
258 if (ec->match_exception_with_space(exception)) {
259 return ec;
260 }
261 ec = ec->next();
262 }
263 return NULL;
264 }
265
266
267 //-----------------------------------------------------------------------------
268
269
270 // Helper used by both find_pc_desc methods.
271 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
272 NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
273 if (!approximate)
274 return pc->pc_offset() == pc_offset;
275 else
276 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
277 }
278
279 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
280 if (initial_pc_desc == NULL) {
281 _pc_descs[0] = NULL; // native method; no PcDescs at all
282 return;
283 }
284 NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
285 // reset the cache by filling it with benign (non-null) values
286 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
287 for (int i = 0; i < cache_size; i++)
288 _pc_descs[i] = initial_pc_desc;
289 }
290
291 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
292 NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
293 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
294
295 // Note: one might think that caching the most recently
296 // read value separately would be a win, but one would be
297 // wrong. When many threads are updating it, the cache
298 // line it's in would bounce between caches, negating
299 // any benefit.
300
301 // In order to prevent race conditions do not load cache elements
302 // repeatedly, but use a local copy:
303 PcDesc* res;
304
305 // Step one: Check the most recently added value.
306 res = _pc_descs[0];
307 if (res == NULL) return NULL; // native method; no PcDescs at all
308 if (match_desc(res, pc_offset, approximate)) {
309 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
310 return res;
311 }
312
313 // Step two: Check the rest of the LRU cache.
314 for (int i = 1; i < cache_size; ++i) {
315 res = _pc_descs[i];
316 if (res->pc_offset() < 0) break; // optimization: skip empty cache
317 if (match_desc(res, pc_offset, approximate)) {
318 NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
319 return res;
320 }
321 }
322
323 // Report failure.
324 return NULL;
325 }
326
327 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
328 NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
329 // Update the LRU cache by shifting pc_desc forward.
330 for (int i = 0; i < cache_size; i++) {
331 PcDesc* next = _pc_descs[i];
332 _pc_descs[i] = pc_desc;
333 pc_desc = next;
334 }
335 }
336
337 // adjust pcs_size so that it is a multiple of both oopSize and
338 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
339 // of oopSize, then 2*sizeof(PcDesc) is)
340 static int adjust_pcs_size(int pcs_size) {
341 int nsize = round_to(pcs_size, oopSize);
342 if ((nsize % sizeof(PcDesc)) != 0) {
343 nsize = pcs_size + sizeof(PcDesc);
344 }
345 assert((nsize % oopSize) == 0, "correct alignment");
346 return nsize;
347 }
348
349 //-----------------------------------------------------------------------------
350
351
352 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
353 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
354 assert(new_entry != NULL,"Must be non null");
355 assert(new_entry->next() == NULL, "Must be null");
356
357 if (exception_cache() != NULL) {
358 new_entry->set_next(exception_cache());
359 }
360 set_exception_cache(new_entry);
361 }
362
363 void nmethod::remove_from_exception_cache(ExceptionCache* ec) {
364 ExceptionCache* prev = NULL;
365 ExceptionCache* curr = exception_cache();
366 assert(curr != NULL, "nothing to remove");
367 // find the previous and next entry of ec
368 while (curr != ec) {
369 prev = curr;
370 curr = curr->next();
371 assert(curr != NULL, "ExceptionCache not found");
372 }
373 // now: curr == ec
374 ExceptionCache* next = curr->next();
375 if (prev == NULL) {
376 set_exception_cache(next);
377 } else {
378 prev->set_next(next);
379 }
380 delete curr;
381 }
382
383
384 // public method for accessing the exception cache
385 // These are the public access methods.
386 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
387 // We never grab a lock to read the exception cache, so we may
388 // have false negatives. This is okay, as it can only happen during
389 // the first few exception lookups for a given nmethod.
390 ExceptionCache* ec = exception_cache();
391 while (ec != NULL) {
392 address ret_val;
393 if ((ret_val = ec->match(exception,pc)) != NULL) {
394 return ret_val;
395 }
396 ec = ec->next();
397 }
398 return NULL;
399 }
400
401
402 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
403 // There are potential race conditions during exception cache updates, so we
404 // must own the ExceptionCache_lock before doing ANY modifications. Because
405 // we don't lock during reads, it is possible to have several threads attempt
406 // to update the cache with the same data. We need to check for already inserted
407 // copies of the current data before adding it.
408
409 MutexLocker ml(ExceptionCache_lock);
410 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
411
412 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
413 target_entry = new ExceptionCache(exception,pc,handler);
414 add_exception_cache_entry(target_entry);
415 }
416 }
417
418
419 //-------------end of code for ExceptionCache--------------
420
421
422 int nmethod::total_size() const {
423 return
424 consts_size() +
425 insts_size() +
426 stub_size() +
427 scopes_data_size() +
428 scopes_pcs_size() +
429 handler_table_size() +
430 nul_chk_table_size();
431 }
432
433 const char* nmethod::compile_kind() const {
434 if (is_osr_method()) return "osr";
435 if (method() != NULL && is_native_method()) return "c2n";
436 return NULL;
437 }
438
439 // Fill in default values for various flag fields
440 void nmethod::init_defaults() {
441 _state = in_use;
442 _marked_for_reclamation = 0;
443 _has_flushed_dependencies = 0;
444 _has_unsafe_access = 0;
445 _has_method_handle_invokes = 0;
446 _lazy_critical_native = 0;
447 _has_wide_vectors = 0;
448 _marked_for_deoptimization = 0;
449 _lock_count = 0;
450 _stack_traversal_mark = 0;
451 _unload_reported = false; // jvmti state
452
453 #ifdef ASSERT
454 _oops_are_stale = false;
455 #endif
456
457 _oops_do_mark_link = NULL;
458 _jmethod_id = NULL;
459 _osr_link = NULL;
460 _scavenge_root_link = NULL;
461 _scavenge_root_state = 0;
462 _compiler = NULL;
463 #if INCLUDE_RTM_OPT
464 _rtm_state = NoRTM;
465 #endif
466 #ifdef HAVE_DTRACE_H
467 _trap_offset = 0;
468 #endif // def HAVE_DTRACE_H
469 }
470
471 nmethod* nmethod::new_native_nmethod(methodHandle method,
472 int compile_id,
473 CodeBuffer *code_buffer,
474 int vep_offset,
475 int frame_complete,
476 int frame_size,
477 ByteSize basic_lock_owner_sp_offset,
478 ByteSize basic_lock_sp_offset,
479 OopMapSet* oop_maps) {
480 code_buffer->finalize_oop_references(method);
481 // create nmethod
482 nmethod* nm = NULL;
483 {
484 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
485 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
486 CodeOffsets offsets;
487 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
488 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
489 nm = new (native_nmethod_size, CompLevel_none) nmethod(method(), native_nmethod_size,
490 compile_id, &offsets,
491 code_buffer, frame_size,
492 basic_lock_owner_sp_offset,
493 basic_lock_sp_offset, oop_maps);
494 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm));
495 if (PrintAssembly && nm != NULL) {
496 Disassembler::decode(nm);
497 }
498 }
499 // verify nmethod
500 debug_only(if (nm) nm->verify();) // might block
501
502 if (nm != NULL) {
503 nm->log_new_nmethod();
504 }
505
506 return nm;
507 }
508
509 #ifdef HAVE_DTRACE_H
510 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
511 CodeBuffer *code_buffer,
512 int vep_offset,
513 int trap_offset,
514 int frame_complete,
515 int frame_size) {
516 code_buffer->finalize_oop_references(method);
517 // create nmethod
518 nmethod* nm = NULL;
519 {
520 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
521 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
522 CodeOffsets offsets;
523 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
524 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
525 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
526
527 nm = new (nmethod_size, CompLevel_none) nmethod(method(), nmethod_size,
528 &offsets, code_buffer, frame_size);
529
530 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
531 if (PrintAssembly && nm != NULL) {
532 Disassembler::decode(nm);
533 }
534 }
535 // verify nmethod
536 debug_only(if (nm) nm->verify();) // might block
537
538 if (nm != NULL) {
539 nm->log_new_nmethod();
540 }
541
542 return nm;
543 }
544
545 #endif // def HAVE_DTRACE_H
546
547 nmethod* nmethod::new_nmethod(methodHandle method,
548 int compile_id,
549 int entry_bci,
550 CodeOffsets* offsets,
551 int orig_pc_offset,
552 DebugInformationRecorder* debug_info,
553 Dependencies* dependencies,
554 CodeBuffer* code_buffer, int frame_size,
555 OopMapSet* oop_maps,
556 ExceptionHandlerTable* handler_table,
557 ImplicitExceptionTable* nul_chk_table,
558 AbstractCompiler* compiler,
559 int comp_level
560 )
561 {
562 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
563 code_buffer->finalize_oop_references(method);
564 // create nmethod
565 nmethod* nm = NULL;
566 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
567 int nmethod_size =
568 allocation_size(code_buffer, sizeof(nmethod))
569 + adjust_pcs_size(debug_info->pcs_size())
570 + round_to(dependencies->size_in_bytes() , oopSize)
571 + round_to(handler_table->size_in_bytes(), oopSize)
572 + round_to(nul_chk_table->size_in_bytes(), oopSize)
573 + round_to(debug_info->data_size() , oopSize);
574
575 nm = new (nmethod_size, comp_level)
576 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
577 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
578 oop_maps,
579 handler_table,
580 nul_chk_table,
581 compiler,
582 comp_level);
583
584 if (nm != NULL) {
585 // To make dependency checking during class loading fast, record
586 // the nmethod dependencies in the classes it is dependent on.
587 // This allows the dependency checking code to simply walk the
588 // class hierarchy above the loaded class, checking only nmethods
589 // which are dependent on those classes. The slow way is to
590 // check every nmethod for dependencies which makes it linear in
591 // the number of methods compiled. For applications with a lot
592 // classes the slow way is too slow.
593 for (Dependencies::DepStream deps(nm); deps.next(); ) {
594 Klass* klass = deps.context_type();
595 if (klass == NULL) {
596 continue; // ignore things like evol_method
597 }
598
599 // record this nmethod as dependent on this klass
600 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
601 }
602 NOT_PRODUCT(nmethod_stats.note_nmethod(nm));
603 if (PrintAssembly || CompilerOracle::has_option_string(method, "PrintAssembly")) {
604 Disassembler::decode(nm);
605 }
606 }
607 }
608 // Do verification and logging outside CodeCache_lock.
609 if (nm != NULL) {
610 // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
611 DEBUG_ONLY(nm->verify();)
612 nm->log_new_nmethod();
613 }
614 return nm;
615 }
616
617
618 // For native wrappers
619 nmethod::nmethod(
620 Method* method,
621 int nmethod_size,
622 int compile_id,
623 CodeOffsets* offsets,
624 CodeBuffer* code_buffer,
625 int frame_size,
626 ByteSize basic_lock_owner_sp_offset,
627 ByteSize basic_lock_sp_offset,
628 OopMapSet* oop_maps )
629 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
630 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
631 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
632 _native_basic_lock_sp_offset(basic_lock_sp_offset)
633 {
634 {
635 debug_only(No_Safepoint_Verifier nsv;)
636 assert_locked_or_safepoint(CodeCache_lock);
637
638 init_defaults();
639 _method = method;
640 _entry_bci = InvocationEntryBci;
641 // We have no exception handler or deopt handler make the
642 // values something that will never match a pc like the nmethod vtable entry
643 _exception_offset = 0;
644 _deoptimize_offset = 0;
645 _deoptimize_mh_offset = 0;
646 _orig_pc_offset = 0;
647
648 _consts_offset = data_offset();
649 _stub_offset = data_offset();
650 _oops_offset = data_offset();
651 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
652 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
653 _scopes_pcs_offset = _scopes_data_offset;
654 _dependencies_offset = _scopes_pcs_offset;
655 _handler_table_offset = _dependencies_offset;
656 _nul_chk_table_offset = _handler_table_offset;
657 _nmethod_end_offset = _nul_chk_table_offset;
658 _compile_id = compile_id;
659 _comp_level = CompLevel_none;
660 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
661 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
662 _osr_entry_point = NULL;
663 _exception_cache = NULL;
664 _pc_desc_cache.reset_to(NULL);
665 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
666
667 code_buffer->copy_values_to(this);
668 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
669 CodeCache::add_scavenge_root_nmethod(this);
670 Universe::heap()->register_nmethod(this);
671 }
672 debug_only(verify_scavenge_root_oops());
673 CodeCache::commit(this);
674 }
675
676 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
677 ttyLocker ttyl; // keep the following output all in one block
678 // This output goes directly to the tty, not the compiler log.
679 // To enable tools to match it up with the compilation activity,
680 // be sure to tag this tty output with the compile ID.
681 if (xtty != NULL) {
682 xtty->begin_head("print_native_nmethod");
683 xtty->method(_method);
684 xtty->stamp();
685 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
686 }
687 // print the header part first
688 print();
689 // then print the requested information
690 if (PrintNativeNMethods) {
691 print_code();
692 if (oop_maps != NULL) {
693 oop_maps->print();
694 }
695 }
696 if (PrintRelocations) {
697 print_relocations();
698 }
699 if (xtty != NULL) {
700 xtty->tail("print_native_nmethod");
701 }
702 }
703 }
704
705 // For dtrace wrappers
706 #ifdef HAVE_DTRACE_H
707 nmethod::nmethod(
708 Method* method,
709 int nmethod_size,
710 CodeOffsets* offsets,
711 CodeBuffer* code_buffer,
712 int frame_size)
713 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
714 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
715 _native_receiver_sp_offset(in_ByteSize(-1)),
716 _native_basic_lock_sp_offset(in_ByteSize(-1))
717 {
718 {
719 debug_only(No_Safepoint_Verifier nsv;)
720 assert_locked_or_safepoint(CodeCache_lock);
721
722 init_defaults();
723 _method = method;
724 _entry_bci = InvocationEntryBci;
725 // We have no exception handler or deopt handler make the
726 // values something that will never match a pc like the nmethod vtable entry
727 _exception_offset = 0;
728 _deoptimize_offset = 0;
729 _deoptimize_mh_offset = 0;
730 _unwind_handler_offset = -1;
731 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
732 _orig_pc_offset = 0;
733 _consts_offset = data_offset();
734 _stub_offset = data_offset();
735 _oops_offset = data_offset();
736 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
737 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
738 _scopes_pcs_offset = _scopes_data_offset;
739 _dependencies_offset = _scopes_pcs_offset;
740 _handler_table_offset = _dependencies_offset;
741 _nul_chk_table_offset = _handler_table_offset;
742 _nmethod_end_offset = _nul_chk_table_offset;
743 _compile_id = 0; // default
744 _comp_level = CompLevel_none;
745 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
746 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
747 _osr_entry_point = NULL;
748 _exception_cache = NULL;
749 _pc_desc_cache.reset_to(NULL);
750 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
751
752 code_buffer->copy_values_to(this);
753 debug_only(verify_scavenge_root_oops());
754 CodeCache::commit(this);
755 }
756
757 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
758 ttyLocker ttyl; // keep the following output all in one block
759 // This output goes directly to the tty, not the compiler log.
760 // To enable tools to match it up with the compilation activity,
761 // be sure to tag this tty output with the compile ID.
762 if (xtty != NULL) {
763 xtty->begin_head("print_dtrace_nmethod");
764 xtty->method(_method);
765 xtty->stamp();
766 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
767 }
768 // print the header part first
769 print();
770 // then print the requested information
771 if (PrintNMethods) {
772 print_code();
773 }
774 if (PrintRelocations) {
775 print_relocations();
776 }
777 if (xtty != NULL) {
778 xtty->tail("print_dtrace_nmethod");
779 }
780 }
781 }
782 #endif // def HAVE_DTRACE_H
783
784 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
785 // Nmethods are allocated on separate heaps and therefore do not share memory with critical CodeBlobs.
786 // We nevertheless define the allocation as critical to make sure all heap memory is used.
787 return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level), true);
788 }
789
790 nmethod::nmethod(
791 Method* method,
792 int nmethod_size,
793 int compile_id,
794 int entry_bci,
795 CodeOffsets* offsets,
796 int orig_pc_offset,
797 DebugInformationRecorder* debug_info,
798 Dependencies* dependencies,
799 CodeBuffer *code_buffer,
800 int frame_size,
801 OopMapSet* oop_maps,
802 ExceptionHandlerTable* handler_table,
803 ImplicitExceptionTable* nul_chk_table,
804 AbstractCompiler* compiler,
805 int comp_level
806 )
807 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
808 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
809 _native_receiver_sp_offset(in_ByteSize(-1)),
810 _native_basic_lock_sp_offset(in_ByteSize(-1))
811 {
812 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
813 {
814 debug_only(No_Safepoint_Verifier nsv;)
815 assert_locked_or_safepoint(CodeCache_lock);
816
817 init_defaults();
818 _method = method;
819 _entry_bci = entry_bci;
820 _compile_id = compile_id;
821 _comp_level = comp_level;
822 _compiler = compiler;
823 _orig_pc_offset = orig_pc_offset;
824 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
825
826 // Section offsets
827 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
828 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
829
830 // Exception handler and deopt handler are in the stub section
831 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
832 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
833 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
834 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
835 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
836 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
837 } else {
838 _deoptimize_mh_offset = -1;
839 }
840 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
841 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
842 } else {
843 _unwind_handler_offset = -1;
844 }
845
846 _oops_offset = data_offset();
847 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
848 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
849
850 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
851 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
852 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
853 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
854 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
855
856 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
857 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
858 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
859 _exception_cache = NULL;
860 _pc_desc_cache.reset_to(scopes_pcs_begin());
861
862 // Copy contents of ScopeDescRecorder to nmethod
863 code_buffer->copy_values_to(this);
864 debug_info->copy_to(this);
865 dependencies->copy_to(this);
866 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
867 CodeCache::add_scavenge_root_nmethod(this);
868 Universe::heap()->register_nmethod(this);
869 }
870 debug_only(verify_scavenge_root_oops());
871
872 CodeCache::commit(this);
873
874 // Copy contents of ExceptionHandlerTable to nmethod
875 handler_table->copy_to(this);
876 nul_chk_table->copy_to(this);
877
878 // we use the information of entry points to find out if a method is
879 // static or non static
880 assert(compiler->is_c2() ||
881 _method->is_static() == (entry_point() == _verified_entry_point),
882 " entry points must be same for static methods and vice versa");
883 }
884
885 bool printnmethods = PrintNMethods
886 || CompilerOracle::should_print(_method)
887 || CompilerOracle::has_option_string(_method, "PrintNMethods");
888 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
889 print_nmethod(printnmethods);
890 }
891 }
892
893
894 // Print a short set of xml attributes to identify this nmethod. The
895 // output should be embedded in some other element.
896 void nmethod::log_identity(xmlStream* log) const {
897 log->print(" compile_id='%d'", compile_id());
898 const char* nm_kind = compile_kind();
899 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
900 if (compiler() != NULL) {
901 log->print(" compiler='%s'", compiler()->name());
902 }
903 if (TieredCompilation) {
904 log->print(" level='%d'", comp_level());
905 }
906 }
907
908
909 #define LOG_OFFSET(log, name) \
910 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
911 log->print(" " XSTR(name) "_offset='%d'" , \
912 (intptr_t)name##_begin() - (intptr_t)this)
913
914
915 void nmethod::log_new_nmethod() const {
916 if (LogCompilation && xtty != NULL) {
917 ttyLocker ttyl;
918 HandleMark hm;
919 xtty->begin_elem("nmethod");
920 log_identity(xtty);
921 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
922 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
923
924 LOG_OFFSET(xtty, relocation);
925 LOG_OFFSET(xtty, consts);
926 LOG_OFFSET(xtty, insts);
927 LOG_OFFSET(xtty, stub);
928 LOG_OFFSET(xtty, scopes_data);
929 LOG_OFFSET(xtty, scopes_pcs);
930 LOG_OFFSET(xtty, dependencies);
931 LOG_OFFSET(xtty, handler_table);
932 LOG_OFFSET(xtty, nul_chk_table);
933 LOG_OFFSET(xtty, oops);
934
935 xtty->method(method());
936 xtty->stamp();
937 xtty->end_elem();
938 }
939 }
940
941 #undef LOG_OFFSET
942
943
944 // Print out more verbose output usually for a newly created nmethod.
945 void nmethod::print_on(outputStream* st, const char* msg) const {
946 if (st != NULL) {
947 ttyLocker ttyl;
948 if (WizardMode) {
949 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
950 st->print_cr(" (" INTPTR_FORMAT ")", this);
951 } else {
952 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
953 }
954 }
955 }
956
957
958 void nmethod::print_nmethod(bool printmethod) {
959 ttyLocker ttyl; // keep the following output all in one block
960 if (xtty != NULL) {
961 xtty->begin_head("print_nmethod");
962 xtty->stamp();
963 xtty->end_head();
964 }
965 // print the header part first
966 print();
967 // then print the requested information
968 if (printmethod) {
969 print_code();
970 print_pcs();
971 if (oop_maps()) {
972 oop_maps()->print();
973 }
974 }
975 if (PrintDebugInfo) {
976 print_scopes();
977 }
978 if (PrintRelocations) {
979 print_relocations();
980 }
981 if (PrintDependencies) {
982 print_dependencies();
983 }
984 if (PrintExceptionHandlers) {
985 print_handler_table();
986 print_nul_chk_table();
987 }
988 if (xtty != NULL) {
989 xtty->tail("print_nmethod");
990 }
991 }
992
993
994 // Promote one word from an assembly-time handle to a live embedded oop.
995 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
996 if (handle == NULL ||
997 // As a special case, IC oops are initialized to 1 or -1.
998 handle == (jobject) Universe::non_oop_word()) {
999 (*dest) = (oop) handle;
1000 } else {
1001 (*dest) = JNIHandles::resolve_non_null(handle);
1002 }
1003 }
1004
1005
1006 // Have to have the same name because it's called by a template
1007 void nmethod::copy_values(GrowableArray<jobject>* array) {
1008 int length = array->length();
1009 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1010 oop* dest = oops_begin();
1011 for (int index = 0 ; index < length; index++) {
1012 initialize_immediate_oop(&dest[index], array->at(index));
1013 }
1014
1015 // Now we can fix up all the oops in the code. We need to do this
1016 // in the code because the assembler uses jobjects as placeholders.
1017 // The code and relocations have already been initialized by the
1018 // CodeBlob constructor, so it is valid even at this early point to
1019 // iterate over relocations and patch the code.
1020 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1021 }
1022
1023 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1024 int length = array->length();
1025 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1026 Metadata** dest = metadata_begin();
1027 for (int index = 0 ; index < length; index++) {
1028 dest[index] = array->at(index);
1029 }
1030 }
1031
1032 bool nmethod::is_at_poll_return(address pc) {
1033 RelocIterator iter(this, pc, pc+1);
1034 while (iter.next()) {
1035 if (iter.type() == relocInfo::poll_return_type)
1036 return true;
1037 }
1038 return false;
1039 }
1040
1041
1042 bool nmethod::is_at_poll_or_poll_return(address pc) {
1043 RelocIterator iter(this, pc, pc+1);
1044 while (iter.next()) {
1045 relocInfo::relocType t = iter.type();
1046 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1047 return true;
1048 }
1049 return false;
1050 }
1051
1052
1053 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1054 // re-patch all oop-bearing instructions, just in case some oops moved
1055 RelocIterator iter(this, begin, end);
1056 while (iter.next()) {
1057 if (iter.type() == relocInfo::oop_type) {
1058 oop_Relocation* reloc = iter.oop_reloc();
1059 if (initialize_immediates && reloc->oop_is_immediate()) {
1060 oop* dest = reloc->oop_addr();
1061 initialize_immediate_oop(dest, (jobject) *dest);
1062 }
1063 // Refresh the oop-related bits of this instruction.
1064 reloc->fix_oop_relocation();
1065 } else if (iter.type() == relocInfo::metadata_type) {
1066 metadata_Relocation* reloc = iter.metadata_reloc();
1067 reloc->fix_metadata_relocation();
1068 }
1069 }
1070 }
1071
1072
1073 void nmethod::verify_oop_relocations() {
1074 // Ensure sure that the code matches the current oop values
1075 RelocIterator iter(this, NULL, NULL);
1076 while (iter.next()) {
1077 if (iter.type() == relocInfo::oop_type) {
1078 oop_Relocation* reloc = iter.oop_reloc();
1079 if (!reloc->oop_is_immediate()) {
1080 reloc->verify_oop_relocation();
1081 }
1082 }
1083 }
1084 }
1085
1086
1087 ScopeDesc* nmethod::scope_desc_at(address pc) {
1088 PcDesc* pd = pc_desc_at(pc);
1089 guarantee(pd != NULL, "scope must be present");
1090 return new ScopeDesc(this, pd->scope_decode_offset(),
1091 pd->obj_decode_offset(), pd->should_reexecute(),
1092 pd->return_oop());
1093 }
1094
1095
1096 void nmethod::clear_inline_caches() {
1097 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1098 if (is_zombie()) {
1099 return;
1100 }
1101
1102 RelocIterator iter(this);
1103 while (iter.next()) {
1104 iter.reloc()->clear_inline_cache();
1105 }
1106 }
1107
1108
1109 void nmethod::cleanup_inline_caches() {
1110
1111 assert_locked_or_safepoint(CompiledIC_lock);
1112
1113 // If the method is not entrant or zombie then a JMP is plastered over the
1114 // first few bytes. If an oop in the old code was there, that oop
1115 // should not get GC'd. Skip the first few bytes of oops on
1116 // not-entrant methods.
1117 address low_boundary = verified_entry_point();
1118 if (!is_in_use()) {
1119 low_boundary += NativeJump::instruction_size;
1120 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1121 // This means that the low_boundary is going to be a little too high.
1122 // This shouldn't matter, since oops of non-entrant methods are never used.
1123 // In fact, why are we bothering to look at oops in a non-entrant method??
1124 }
1125
1126 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1127 ResourceMark rm;
1128 RelocIterator iter(this, low_boundary);
1129 while(iter.next()) {
1130 switch(iter.type()) {
1131 case relocInfo::virtual_call_type:
1132 case relocInfo::opt_virtual_call_type: {
1133 CompiledIC *ic = CompiledIC_at(iter.reloc());
1134 // Ok, to lookup references to zombies here
1135 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1136 if( cb != NULL && cb->is_nmethod() ) {
1137 nmethod* nm = (nmethod*)cb;
1138 // Clean inline caches pointing to both zombie and not_entrant methods
1139 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1140 }
1141 break;
1142 }
1143 case relocInfo::static_call_type: {
1144 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1145 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1146 if( cb != NULL && cb->is_nmethod() ) {
1147 nmethod* nm = (nmethod*)cb;
1148 // Clean inline caches pointing to both zombie and not_entrant methods
1149 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1150 }
1151 break;
1152 }
1153 }
1154 }
1155 }
1156
1157 // This is a private interface with the sweeper.
1158 void nmethod::mark_as_seen_on_stack() {
1159 assert(is_alive(), "Must be an alive method");
1160 // Set the traversal mark to ensure that the sweeper does 2
1161 // cleaning passes before moving to zombie.
1162 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1163 }
1164
1165 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1166 // there are no activations on the stack, not in use by the VM,
1167 // and not in use by the ServiceThread)
1168 bool nmethod::can_not_entrant_be_converted() {
1169 assert(is_not_entrant(), "must be a non-entrant method");
1170
1171 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1172 // count can be greater than the stack traversal count before it hits the
1173 // nmethod for the second time.
1174 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1175 !is_locked_by_vm();
1176 }
1177
1178 void nmethod::inc_decompile_count() {
1179 if (!is_compiled_by_c2()) return;
1180 // Could be gated by ProfileTraps, but do not bother...
1181 Method* m = method();
1182 if (m == NULL) return;
1183 MethodData* mdo = m->method_data();
1184 if (mdo == NULL) return;
1185 // There is a benign race here. See comments in methodData.hpp.
1186 mdo->inc_decompile_count();
1187 }
1188
1189 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1190
1191 post_compiled_method_unload();
1192
1193 // Since this nmethod is being unloaded, make sure that dependencies
1194 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1195 // indicate that this work is being done during a GC.
1196 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1197 assert(is_alive != NULL, "Should be non-NULL");
1198 // A non-NULL is_alive closure indicates that this is being called during GC.
1199 flush_dependencies(is_alive);
1200
1201 // Break cycle between nmethod & method
1202 if (TraceClassUnloading && WizardMode) {
1203 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1204 " unloadable], Method*(" INTPTR_FORMAT
1205 "), cause(" INTPTR_FORMAT ")",
1206 this, (address)_method, (address)cause);
1207 if (!Universe::heap()->is_gc_active())
1208 cause->klass()->print();
1209 }
1210 // Unlink the osr method, so we do not look this up again
1211 if (is_osr_method()) {
1212 invalidate_osr_method();
1213 }
1214 // If _method is already NULL the Method* is about to be unloaded,
1215 // so we don't have to break the cycle. Note that it is possible to
1216 // have the Method* live here, in case we unload the nmethod because
1217 // it is pointing to some oop (other than the Method*) being unloaded.
1218 if (_method != NULL) {
1219 // OSR methods point to the Method*, but the Method* does not
1220 // point back!
1221 if (_method->code() == this) {
1222 _method->clear_code(); // Break a cycle
1223 }
1224 _method = NULL; // Clear the method of this dead nmethod
1225 }
1226 // Make the class unloaded - i.e., change state and notify sweeper
1227 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1228 if (is_in_use()) {
1229 // Transitioning directly from live to unloaded -- so
1230 // we need to force a cache clean-up; remember this
1231 // for later on.
1232 CodeCache::set_needs_cache_clean(true);
1233 }
1234 _state = unloaded;
1235
1236 // Log the unloading.
1237 log_state_change();
1238
1239 // The Method* is gone at this point
1240 assert(_method == NULL, "Tautology");
1241
1242 set_osr_link(NULL);
1243 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1244 NMethodSweeper::report_state_change(this);
1245 }
1246
1247 void nmethod::invalidate_osr_method() {
1248 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1249 // Remove from list of active nmethods
1250 if (method() != NULL)
1251 method()->method_holder()->remove_osr_nmethod(this);
1252 // Set entry as invalid
1253 _entry_bci = InvalidOSREntryBci;
1254 }
1255
1256 void nmethod::log_state_change() const {
1257 if (LogCompilation) {
1258 if (xtty != NULL) {
1259 ttyLocker ttyl; // keep the following output all in one block
1260 if (_state == unloaded) {
1261 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1262 os::current_thread_id());
1263 } else {
1264 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1265 os::current_thread_id(),
1266 (_state == zombie ? " zombie='1'" : ""));
1267 }
1268 log_identity(xtty);
1269 xtty->stamp();
1270 xtty->end_elem();
1271 }
1272 }
1273 if (PrintCompilation && _state != unloaded) {
1274 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1275 }
1276 }
1277
1278 /**
1279 * Common functionality for both make_not_entrant and make_zombie
1280 */
1281 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1282 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1283 assert(!is_zombie(), "should not already be a zombie");
1284
1285 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1286 nmethodLocker nml(this);
1287 methodHandle the_method(method());
1288 No_Safepoint_Verifier nsv;
1289
1290 // during patching, depending on the nmethod state we must notify the GC that
1291 // code has been unloaded, unregistering it. We cannot do this right while
1292 // holding the Patching_lock because we need to use the CodeCache_lock. This
1293 // would be prone to deadlocks.
1294 // This flag is used to remember whether we need to later lock and unregister.
1295 bool nmethod_needs_unregister = false;
1296
1297 {
1298 // invalidate osr nmethod before acquiring the patching lock since
1299 // they both acquire leaf locks and we don't want a deadlock.
1300 // This logic is equivalent to the logic below for patching the
1301 // verified entry point of regular methods.
1302 if (is_osr_method()) {
1303 // this effectively makes the osr nmethod not entrant
1304 invalidate_osr_method();
1305 }
1306
1307 // Enter critical section. Does not block for safepoint.
1308 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1309
1310 if (_state == state) {
1311 // another thread already performed this transition so nothing
1312 // to do, but return false to indicate this.
1313 return false;
1314 }
1315
1316 // The caller can be calling the method statically or through an inline
1317 // cache call.
1318 if (!is_osr_method() && !is_not_entrant()) {
1319 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1320 SharedRuntime::get_handle_wrong_method_stub());
1321 }
1322
1323 if (is_in_use()) {
1324 // It's a true state change, so mark the method as decompiled.
1325 // Do it only for transition from alive.
1326 inc_decompile_count();
1327 }
1328
1329 // If the state is becoming a zombie, signal to unregister the nmethod with
1330 // the heap.
1331 // This nmethod may have already been unloaded during a full GC.
1332 if ((state == zombie) && !is_unloaded()) {
1333 nmethod_needs_unregister = true;
1334 }
1335
1336 // Must happen before state change. Otherwise we have a race condition in
1337 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1338 // transition its state from 'not_entrant' to 'zombie' without having to wait
1339 // for stack scanning.
1340 if (state == not_entrant) {
1341 mark_as_seen_on_stack();
1342 OrderAccess::storestore();
1343 }
1344
1345 // Change state
1346 _state = state;
1347
1348 // Log the transition once
1349 log_state_change();
1350
1351 // Remove nmethod from method.
1352 // We need to check if both the _code and _from_compiled_code_entry_point
1353 // refer to this nmethod because there is a race in setting these two fields
1354 // in Method* as seen in bugid 4947125.
1355 // If the vep() points to the zombie nmethod, the memory for the nmethod
1356 // could be flushed and the compiler and vtable stubs could still call
1357 // through it.
1358 if (method() != NULL && (method()->code() == this ||
1359 method()->from_compiled_entry() == verified_entry_point())) {
1360 HandleMark hm;
1361 method()->clear_code();
1362 }
1363 } // leave critical region under Patching_lock
1364
1365 // When the nmethod becomes zombie it is no longer alive so the
1366 // dependencies must be flushed. nmethods in the not_entrant
1367 // state will be flushed later when the transition to zombie
1368 // happens or they get unloaded.
1369 if (state == zombie) {
1370 {
1371 // Flushing dependecies must be done before any possible
1372 // safepoint can sneak in, otherwise the oops used by the
1373 // dependency logic could have become stale.
1374 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1375 if (nmethod_needs_unregister) {
1376 Universe::heap()->unregister_nmethod(this);
1377 }
1378 flush_dependencies(NULL);
1379 }
1380
1381 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1382 // event and it hasn't already been reported for this nmethod then
1383 // report it now. The event may have been reported earilier if the GC
1384 // marked it for unloading). JvmtiDeferredEventQueue support means
1385 // we no longer go to a safepoint here.
1386 post_compiled_method_unload();
1387
1388 #ifdef ASSERT
1389 // It's no longer safe to access the oops section since zombie
1390 // nmethods aren't scanned for GC.
1391 _oops_are_stale = true;
1392 #endif
1393 // the Method may be reclaimed by class unloading now that the
1394 // nmethod is in zombie state
1395 set_method(NULL);
1396 } else {
1397 assert(state == not_entrant, "other cases may need to be handled differently");
1398 }
1399
1400 if (TraceCreateZombies) {
1401 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1402 }
1403
1404 NMethodSweeper::report_state_change(this);
1405 return true;
1406 }
1407
1408 void nmethod::flush() {
1409 // Note that there are no valid oops in the nmethod anymore.
1410 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1411 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1412
1413 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1414 assert_locked_or_safepoint(CodeCache_lock);
1415
1416 // completely deallocate this method
1417 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1418 if (PrintMethodFlushing) {
1419 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1420 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(_comp_level))/1024);
1421 }
1422
1423 // We need to deallocate any ExceptionCache data.
1424 // Note that we do not need to grab the nmethod lock for this, it
1425 // better be thread safe if we're disposing of it!
1426 ExceptionCache* ec = exception_cache();
1427 set_exception_cache(NULL);
1428 while(ec != NULL) {
1429 ExceptionCache* next = ec->next();
1430 delete ec;
1431 ec = next;
1432 }
1433
1434 if (on_scavenge_root_list()) {
1435 CodeCache::drop_scavenge_root_nmethod(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, CodeCache::get_code_blob_type(_comp_level));
1445 }
1446
1447 //
1448 // Notify all classes this nmethod is dependent on that it is no
1449 // longer dependent. This should only be called in two situations.
1450 // First, when a nmethod transitions to a zombie all dependents need
1451 // to be clear. Since zombification happens at a safepoint there's no
1452 // synchronization issues. The second place is a little more tricky.
1453 // During phase 1 of mark sweep class unloading may happen and as a
1454 // result some nmethods may get unloaded. In this case the flushing
1455 // of dependencies must happen during phase 1 since after GC any
1456 // dependencies in the unloaded nmethod won't be updated, so
1457 // traversing the dependency information in unsafe. In that case this
1458 // function is called with a non-NULL argument and this function only
1459 // notifies instanceKlasses that are reachable
1460
1461 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1462 assert_locked_or_safepoint(CodeCache_lock);
1463 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1464 "is_alive is non-NULL if and only if we are called during GC");
1465 if (!has_flushed_dependencies()) {
1466 set_has_flushed_dependencies();
1467 for (Dependencies::DepStream deps(this); deps.next(); ) {
1468 Klass* klass = deps.context_type();
1469 if (klass == NULL) continue; // ignore things like evol_method
1470
1471 // During GC the is_alive closure is non-NULL, and is used to
1472 // determine liveness of dependees that need to be updated.
1473 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1474 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1475 }
1476 }
1477 }
1478 }
1479
1480
1481 // If this oop is not live, the nmethod can be unloaded.
1482 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1483 assert(root != NULL, "just checking");
1484 oop obj = *root;
1485 if (obj == NULL || is_alive->do_object_b(obj)) {
1486 return false;
1487 }
1488
1489 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1490 // simply because one of its constant oops has gone dead.
1491 // No actual classes need to be unloaded in order for this to occur.
1492 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1493 make_unloaded(is_alive, obj);
1494 return true;
1495 }
1496
1497 // ------------------------------------------------------------------
1498 // post_compiled_method_load_event
1499 // new method for install_code() path
1500 // Transfer information from compilation to jvmti
1501 void nmethod::post_compiled_method_load_event() {
1502
1503 Method* moop = method();
1504 HOTSPOT_COMPILED_METHOD_LOAD(
1505 (char *) moop->klass_name()->bytes(),
1506 moop->klass_name()->utf8_length(),
1507 (char *) moop->name()->bytes(),
1508 moop->name()->utf8_length(),
1509 (char *) moop->signature()->bytes(),
1510 moop->signature()->utf8_length(),
1511 insts_begin(), insts_size());
1512
1513 if (JvmtiExport::should_post_compiled_method_load() ||
1514 JvmtiExport::should_post_compiled_method_unload()) {
1515 get_and_cache_jmethod_id();
1516 }
1517
1518 if (JvmtiExport::should_post_compiled_method_load()) {
1519 // Let the Service thread (which is a real Java thread) post the event
1520 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1521 JvmtiDeferredEventQueue::enqueue(
1522 JvmtiDeferredEvent::compiled_method_load_event(this));
1523 }
1524 }
1525
1526 jmethodID nmethod::get_and_cache_jmethod_id() {
1527 if (_jmethod_id == NULL) {
1528 // Cache the jmethod_id since it can no longer be looked up once the
1529 // method itself has been marked for unloading.
1530 _jmethod_id = method()->jmethod_id();
1531 }
1532 return _jmethod_id;
1533 }
1534
1535 void nmethod::post_compiled_method_unload() {
1536 if (unload_reported()) {
1537 // During unloading we transition to unloaded and then to zombie
1538 // and the unloading is reported during the first transition.
1539 return;
1540 }
1541
1542 assert(_method != NULL && !is_unloaded(), "just checking");
1543 DTRACE_METHOD_UNLOAD_PROBE(method());
1544
1545 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1546 // post the event. Sometime later this nmethod will be made a zombie
1547 // by the sweeper but the Method* will not be valid at that point.
1548 // If the _jmethod_id is null then no load event was ever requested
1549 // so don't bother posting the unload. The main reason for this is
1550 // that the jmethodID is a weak reference to the Method* so if
1551 // it's being unloaded there's no way to look it up since the weak
1552 // ref will have been cleared.
1553 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1554 assert(!unload_reported(), "already unloaded");
1555 JvmtiDeferredEvent event =
1556 JvmtiDeferredEvent::compiled_method_unload_event(this,
1557 _jmethod_id, insts_begin());
1558 if (SafepointSynchronize::is_at_safepoint()) {
1559 // Don't want to take the queueing lock. Add it as pending and
1560 // it will get enqueued later.
1561 JvmtiDeferredEventQueue::add_pending_event(event);
1562 } else {
1563 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1564 JvmtiDeferredEventQueue::enqueue(event);
1565 }
1566 }
1567
1568 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1569 // any time. As the nmethod is being unloaded now we mark it has
1570 // having the unload event reported - this will ensure that we don't
1571 // attempt to report the event in the unlikely scenario where the
1572 // event is enabled at the time the nmethod is made a zombie.
1573 set_unload_reported();
1574 }
1575
1576 // This is called at the end of the strong tracing/marking phase of a
1577 // GC to unload an nmethod if it contains otherwise unreachable
1578 // oops.
1579
1580 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1581 // Make sure the oop's ready to receive visitors
1582 assert(!is_zombie() && !is_unloaded(),
1583 "should not call follow on zombie or unloaded nmethod");
1584
1585 // If the method is not entrant then a JMP is plastered over the
1586 // first few bytes. If an oop in the old code was there, that oop
1587 // should not get GC'd. Skip the first few bytes of oops on
1588 // not-entrant methods.
1589 address low_boundary = verified_entry_point();
1590 if (is_not_entrant()) {
1591 low_boundary += NativeJump::instruction_size;
1592 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1593 // (See comment above.)
1594 }
1595
1596 // The RedefineClasses() API can cause the class unloading invariant
1597 // to no longer be true. See jvmtiExport.hpp for details.
1598 // Also, leave a debugging breadcrumb in local flag.
1599 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1600 if (a_class_was_redefined) {
1601 // This set of the unloading_occurred flag is done before the
1602 // call to post_compiled_method_unload() so that the unloading
1603 // of this nmethod is reported.
1604 unloading_occurred = true;
1605 }
1606
1607 // Exception cache
1608 ExceptionCache* ec = exception_cache();
1609 while (ec != NULL) {
1610 Klass* ex_klass = ec->exception_type();
1611 ExceptionCache* next_ec = ec->next();
1612 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
1613 remove_from_exception_cache(ec);
1614 }
1615 ec = next_ec;
1616 }
1617
1618 // If class unloading occurred we first iterate over all inline caches and
1619 // clear ICs where the cached oop is referring to an unloaded klass or method.
1620 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1621 // iteration below.
1622 if (unloading_occurred) {
1623 RelocIterator iter(this, low_boundary);
1624 while(iter.next()) {
1625 if (iter.type() == relocInfo::virtual_call_type) {
1626 CompiledIC *ic = CompiledIC_at(iter.reloc());
1627 if (ic->is_icholder_call()) {
1628 // The only exception is compiledICHolder oops which may
1629 // yet be marked below. (We check this further below).
1630 CompiledICHolder* cichk_oop = ic->cached_icholder();
1631 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1632 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1633 continue;
1634 }
1635 } else {
1636 Metadata* ic_oop = ic->cached_metadata();
1637 if (ic_oop != NULL) {
1638 if (ic_oop->is_klass()) {
1639 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1640 continue;
1641 }
1642 } else if (ic_oop->is_method()) {
1643 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1644 continue;
1645 }
1646 } else {
1647 ShouldNotReachHere();
1648 }
1649 }
1650 }
1651 ic->set_to_clean();
1652 }
1653 }
1654 }
1655
1656 // Compiled code
1657 {
1658 RelocIterator iter(this, low_boundary);
1659 while (iter.next()) {
1660 if (iter.type() == relocInfo::oop_type) {
1661 oop_Relocation* r = iter.oop_reloc();
1662 // In this loop, we must only traverse those oops directly embedded in
1663 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1664 assert(1 == (r->oop_is_immediate()) +
1665 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1666 "oop must be found in exactly one place");
1667 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1668 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1669 return;
1670 }
1671 }
1672 }
1673 }
1674 }
1675
1676
1677 // Scopes
1678 for (oop* p = oops_begin(); p < oops_end(); p++) {
1679 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1680 if (can_unload(is_alive, p, unloading_occurred)) {
1681 return;
1682 }
1683 }
1684
1685 // Ensure that all metadata is still alive
1686 verify_metadata_loaders(low_boundary, is_alive);
1687 }
1688
1689 #ifdef ASSERT
1690
1691 class CheckClass : AllStatic {
1692 static BoolObjectClosure* _is_alive;
1693
1694 // Check class_loader is alive for this bit of metadata.
1695 static void check_class(Metadata* md) {
1696 Klass* klass = NULL;
1697 if (md->is_klass()) {
1698 klass = ((Klass*)md);
1699 } else if (md->is_method()) {
1700 klass = ((Method*)md)->method_holder();
1701 } else if (md->is_methodData()) {
1702 klass = ((MethodData*)md)->method()->method_holder();
1703 } else {
1704 md->print();
1705 ShouldNotReachHere();
1706 }
1707 assert(klass->is_loader_alive(_is_alive), "must be alive");
1708 }
1709 public:
1710 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
1711 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
1712 _is_alive = is_alive;
1713 nm->metadata_do(check_class);
1714 }
1715 };
1716
1717 // This is called during a safepoint so can use static data
1718 BoolObjectClosure* CheckClass::_is_alive = NULL;
1719 #endif // ASSERT
1720
1721
1722 // Processing of oop references should have been sufficient to keep
1723 // all strong references alive. Any weak references should have been
1724 // cleared as well. Visit all the metadata and ensure that it's
1725 // really alive.
1726 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
1727 #ifdef ASSERT
1728 RelocIterator iter(this, low_boundary);
1729 while (iter.next()) {
1730 // static_stub_Relocations may have dangling references to
1731 // Method*s so trim them out here. Otherwise it looks like
1732 // compiled code is maintaining a link to dead metadata.
1733 address static_call_addr = NULL;
1734 if (iter.type() == relocInfo::opt_virtual_call_type) {
1735 CompiledIC* cic = CompiledIC_at(iter.reloc());
1736 if (!cic->is_call_to_interpreted()) {
1737 static_call_addr = iter.addr();
1738 }
1739 } else if (iter.type() == relocInfo::static_call_type) {
1740 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
1741 if (!csc->is_call_to_interpreted()) {
1742 static_call_addr = iter.addr();
1743 }
1744 }
1745 if (static_call_addr != NULL) {
1746 RelocIterator sciter(this, low_boundary);
1747 while (sciter.next()) {
1748 if (sciter.type() == relocInfo::static_stub_type &&
1749 sciter.static_stub_reloc()->static_call() == static_call_addr) {
1750 sciter.static_stub_reloc()->clear_inline_cache();
1751 }
1752 }
1753 }
1754 }
1755 // Check that the metadata embedded in the nmethod is alive
1756 CheckClass::do_check_class(is_alive, this);
1757 #endif
1758 }
1759
1760
1761 // Iterate over metadata calling this function. Used by RedefineClasses
1762 void nmethod::metadata_do(void f(Metadata*)) {
1763 address low_boundary = verified_entry_point();
1764 if (is_not_entrant()) {
1765 low_boundary += NativeJump::instruction_size;
1766 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1767 // (See comment above.)
1768 }
1769 {
1770 // Visit all immediate references that are embedded in the instruction stream.
1771 RelocIterator iter(this, low_boundary);
1772 while (iter.next()) {
1773 if (iter.type() == relocInfo::metadata_type ) {
1774 metadata_Relocation* r = iter.metadata_reloc();
1775 // In this lmetadata, we must only follow those metadatas directly embedded in
1776 // the code. Other metadatas (oop_index>0) are seen as part of
1777 // the metadata section below.
1778 assert(1 == (r->metadata_is_immediate()) +
1779 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1780 "metadata must be found in exactly one place");
1781 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1782 Metadata* md = r->metadata_value();
1783 f(md);
1784 }
1785 } else if (iter.type() == relocInfo::virtual_call_type) {
1786 // Check compiledIC holders associated with this nmethod
1787 CompiledIC *ic = CompiledIC_at(iter.reloc());
1788 if (ic->is_icholder_call()) {
1789 CompiledICHolder* cichk = ic->cached_icholder();
1790 f(cichk->holder_method());
1791 f(cichk->holder_klass());
1792 } else {
1793 Metadata* ic_oop = ic->cached_metadata();
1794 if (ic_oop != NULL) {
1795 f(ic_oop);
1796 }
1797 }
1798 }
1799 }
1800 }
1801
1802 // Visit the metadata section
1803 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1804 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
1805 Metadata* md = *p;
1806 f(md);
1807 }
1808
1809 // Call function Method*, not embedded in these other places.
1810 if (_method != NULL) f(_method);
1811 }
1812
1813 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1814 // make sure the oops ready to receive visitors
1815 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1816 assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1817
1818 // If the method is not entrant or zombie then a JMP is plastered over the
1819 // first few bytes. If an oop in the old code was there, that oop
1820 // should not get GC'd. Skip the first few bytes of oops on
1821 // not-entrant methods.
1822 address low_boundary = verified_entry_point();
1823 if (is_not_entrant()) {
1824 low_boundary += NativeJump::instruction_size;
1825 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1826 // (See comment above.)
1827 }
1828
1829 RelocIterator iter(this, low_boundary);
1830
1831 while (iter.next()) {
1832 if (iter.type() == relocInfo::oop_type ) {
1833 oop_Relocation* r = iter.oop_reloc();
1834 // In this loop, we must only follow those oops directly embedded in
1835 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1836 assert(1 == (r->oop_is_immediate()) +
1837 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1838 "oop must be found in exactly one place");
1839 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1840 f->do_oop(r->oop_addr());
1841 }
1842 }
1843 }
1844
1845 // Scopes
1846 // This includes oop constants not inlined in the code stream.
1847 for (oop* p = oops_begin(); p < oops_end(); p++) {
1848 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1849 f->do_oop(p);
1850 }
1851 }
1852
1853 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1854
1855 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1856
1857 // An nmethod is "marked" if its _mark_link is set non-null.
1858 // Even if it is the end of the linked list, it will have a non-null link value,
1859 // as long as it is on the list.
1860 // This code must be MP safe, because it is used from parallel GC passes.
1861 bool nmethod::test_set_oops_do_mark() {
1862 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1863 nmethod* observed_mark_link = _oops_do_mark_link;
1864 if (observed_mark_link == NULL) {
1865 // Claim this nmethod for this thread to mark.
1866 observed_mark_link = (nmethod*)
1867 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1868 if (observed_mark_link == NULL) {
1869
1870 // Atomically append this nmethod (now claimed) to the head of the list:
1871 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1872 for (;;) {
1873 nmethod* required_mark_nmethods = observed_mark_nmethods;
1874 _oops_do_mark_link = required_mark_nmethods;
1875 observed_mark_nmethods = (nmethod*)
1876 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1877 if (observed_mark_nmethods == required_mark_nmethods)
1878 break;
1879 }
1880 // Mark was clear when we first saw this guy.
1881 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
1882 return false;
1883 }
1884 }
1885 // On fall through, another racing thread marked this nmethod before we did.
1886 return true;
1887 }
1888
1889 void nmethod::oops_do_marking_prologue() {
1890 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
1891 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1892 // We use cmpxchg_ptr instead of regular assignment here because the user
1893 // may fork a bunch of threads, and we need them all to see the same state.
1894 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1895 guarantee(observed == NULL, "no races in this sequential code");
1896 }
1897
1898 void nmethod::oops_do_marking_epilogue() {
1899 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1900 nmethod* cur = _oops_do_mark_nmethods;
1901 while (cur != NMETHOD_SENTINEL) {
1902 assert(cur != NULL, "not NULL-terminated");
1903 nmethod* next = cur->_oops_do_mark_link;
1904 cur->_oops_do_mark_link = NULL;
1905 cur->fix_oop_relocations();
1906 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
1907 cur = next;
1908 }
1909 void* required = _oops_do_mark_nmethods;
1910 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1911 guarantee(observed == required, "no races in this sequential code");
1912 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
1913 }
1914
1915 class DetectScavengeRoot: public OopClosure {
1916 bool _detected_scavenge_root;
1917 public:
1918 DetectScavengeRoot() : _detected_scavenge_root(false)
1919 { NOT_PRODUCT(_print_nm = NULL); }
1920 bool detected_scavenge_root() { return _detected_scavenge_root; }
1921 virtual void do_oop(oop* p) {
1922 if ((*p) != NULL && (*p)->is_scavengable()) {
1923 NOT_PRODUCT(maybe_print(p));
1924 _detected_scavenge_root = true;
1925 }
1926 }
1927 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1928
1929 #ifndef PRODUCT
1930 nmethod* _print_nm;
1931 void maybe_print(oop* p) {
1932 if (_print_nm == NULL) return;
1933 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
1934 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
1935 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
1936 (void *)(*p), (intptr_t)p);
1937 (*p)->print();
1938 }
1939 #endif //PRODUCT
1940 };
1941
1942 bool nmethod::detect_scavenge_root_oops() {
1943 DetectScavengeRoot detect_scavenge_root;
1944 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
1945 oops_do(&detect_scavenge_root);
1946 return detect_scavenge_root.detected_scavenge_root();
1947 }
1948
1949 // Method that knows how to preserve outgoing arguments at call. This method must be
1950 // called with a frame corresponding to a Java invoke
1951 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1952 #ifndef SHARK
1953 if (!method()->is_native()) {
1954 SimpleScopeDesc ssd(this, fr.pc());
1955 Bytecode_invoke call(ssd.method(), ssd.bci());
1956 bool has_receiver = call.has_receiver();
1957 bool has_appendix = call.has_appendix();
1958 Symbol* signature = call.signature();
1959 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
1960 }
1961 #endif // !SHARK
1962 }
1963
1964
1965 oop nmethod::embeddedOop_at(u_char* p) {
1966 RelocIterator iter(this, p, p + 1);
1967 while (iter.next())
1968 if (iter.type() == relocInfo::oop_type) {
1969 return iter.oop_reloc()->oop_value();
1970 }
1971 return NULL;
1972 }
1973
1974
1975 inline bool includes(void* p, void* from, void* to) {
1976 return from <= p && p < to;
1977 }
1978
1979
1980 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1981 assert(count >= 2, "must be sentinel values, at least");
1982
1983 #ifdef ASSERT
1984 // must be sorted and unique; we do a binary search in find_pc_desc()
1985 int prev_offset = pcs[0].pc_offset();
1986 assert(prev_offset == PcDesc::lower_offset_limit,
1987 "must start with a sentinel");
1988 for (int i = 1; i < count; i++) {
1989 int this_offset = pcs[i].pc_offset();
1990 assert(this_offset > prev_offset, "offsets must be sorted");
1991 prev_offset = this_offset;
1992 }
1993 assert(prev_offset == PcDesc::upper_offset_limit,
1994 "must end with a sentinel");
1995 #endif //ASSERT
1996
1997 // Search for MethodHandle invokes and tag the nmethod.
1998 for (int i = 0; i < count; i++) {
1999 if (pcs[i].is_method_handle_invoke()) {
2000 set_has_method_handle_invokes(true);
2001 break;
2002 }
2003 }
2004 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2005
2006 int size = count * sizeof(PcDesc);
2007 assert(scopes_pcs_size() >= size, "oob");
2008 memcpy(scopes_pcs_begin(), pcs, size);
2009
2010 // Adjust the final sentinel downward.
2011 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2012 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2013 last_pc->set_pc_offset(content_size() + 1);
2014 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2015 // Fill any rounding gaps with copies of the last record.
2016 last_pc[1] = last_pc[0];
2017 }
2018 // The following assert could fail if sizeof(PcDesc) is not
2019 // an integral multiple of oopSize (the rounding term).
2020 // If it fails, change the logic to always allocate a multiple
2021 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2022 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2023 }
2024
2025 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2026 assert(scopes_data_size() >= size, "oob");
2027 memcpy(scopes_data_begin(), buffer, size);
2028 }
2029
2030
2031 #ifdef ASSERT
2032 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2033 PcDesc* lower = nm->scopes_pcs_begin();
2034 PcDesc* upper = nm->scopes_pcs_end();
2035 lower += 1; // exclude initial sentinel
2036 PcDesc* res = NULL;
2037 for (PcDesc* p = lower; p < upper; p++) {
2038 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2039 if (match_desc(p, pc_offset, approximate)) {
2040 if (res == NULL)
2041 res = p;
2042 else
2043 res = (PcDesc*) badAddress;
2044 }
2045 }
2046 return res;
2047 }
2048 #endif
2049
2050
2051 // Finds a PcDesc with real-pc equal to "pc"
2052 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2053 address base_address = code_begin();
2054 if ((pc < base_address) ||
2055 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2056 return NULL; // PC is wildly out of range
2057 }
2058 int pc_offset = (int) (pc - base_address);
2059
2060 // Check the PcDesc cache if it contains the desired PcDesc
2061 // (This as an almost 100% hit rate.)
2062 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2063 if (res != NULL) {
2064 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2065 return res;
2066 }
2067
2068 // Fallback algorithm: quasi-linear search for the PcDesc
2069 // Find the last pc_offset less than the given offset.
2070 // The successor must be the required match, if there is a match at all.
2071 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2072 PcDesc* lower = scopes_pcs_begin();
2073 PcDesc* upper = scopes_pcs_end();
2074 upper -= 1; // exclude final sentinel
2075 if (lower >= upper) return NULL; // native method; no PcDescs at all
2076
2077 #define assert_LU_OK \
2078 /* invariant on lower..upper during the following search: */ \
2079 assert(lower->pc_offset() < pc_offset, "sanity"); \
2080 assert(upper->pc_offset() >= pc_offset, "sanity")
2081 assert_LU_OK;
2082
2083 // Use the last successful return as a split point.
2084 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2085 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2086 if (mid->pc_offset() < pc_offset) {
2087 lower = mid;
2088 } else {
2089 upper = mid;
2090 }
2091
2092 // Take giant steps at first (4096, then 256, then 16, then 1)
2093 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2094 const int RADIX = (1 << LOG2_RADIX);
2095 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2096 while ((mid = lower + step) < upper) {
2097 assert_LU_OK;
2098 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2099 if (mid->pc_offset() < pc_offset) {
2100 lower = mid;
2101 } else {
2102 upper = mid;
2103 break;
2104 }
2105 }
2106 assert_LU_OK;
2107 }
2108
2109 // Sneak up on the value with a linear search of length ~16.
2110 while (true) {
2111 assert_LU_OK;
2112 mid = lower + 1;
2113 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2114 if (mid->pc_offset() < pc_offset) {
2115 lower = mid;
2116 } else {
2117 upper = mid;
2118 break;
2119 }
2120 }
2121 #undef assert_LU_OK
2122
2123 if (match_desc(upper, pc_offset, approximate)) {
2124 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2125 _pc_desc_cache.add_pc_desc(upper);
2126 return upper;
2127 } else {
2128 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2129 return NULL;
2130 }
2131 }
2132
2133
2134 void nmethod::check_all_dependencies(DepChange& changes) {
2135 // Checked dependencies are allocated into this ResourceMark
2136 ResourceMark rm;
2137
2138 // Turn off dependency tracing while actually testing dependencies.
2139 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
2140
2141 typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
2142 &DependencySignature::equals, 11027> DepTable;
2143
2144 DepTable* table = new DepTable();
2145
2146 // Iterate over live nmethods and check dependencies of all nmethods that are not
2147 // marked for deoptimization. A particular dependency is only checked once.
2148 for (int code_blob_type = CodeBlobType::MethodNonProfiled; code_blob_type <= CodeBlobType::MethodProfiled; ++code_blob_type) {
2149 // Only notify for live nmethods
2150 nmethod* nm = (nmethod*) CodeCache::first_alive_blob(code_blob_type);
2151 while (nm != NULL) {
2152 if (!nm->is_marked_for_deoptimization()) {
2153 for (Dependencies::DepStream deps(nm); deps.next(); ) {
2154 // Construct abstraction of a dependency.
2155 DependencySignature* current_sig = new DependencySignature(deps);
2156
2157 // Determine if dependency is already checked. table->put(...) returns
2158 // 'true' if the dependency is added (i.e., was not in the hashtable).
2159 if (table->put(*current_sig, 1)) {
2160 if (deps.check_dependency() != NULL) {
2161 // Dependency checking failed. Print out information about the failed
2162 // dependency and finally fail with an assert. We can fail here, since
2163 // dependency checking is never done in a product build.
2164 changes.print();
2165 nm->print();
2166 nm->print_dependencies();
2167 assert(false, "Should have been marked for deoptimization");
2168 }
2169 }
2170 }
2171 }
2172 nm = (nmethod*) CodeCache::next_alive_blob(nm, code_blob_type);
2173 }
2174 }
2175 }
2176
2177 bool nmethod::check_dependency_on(DepChange& changes) {
2178 // What has happened:
2179 // 1) a new class dependee has been added
2180 // 2) dependee and all its super classes have been marked
2181 bool found_check = false; // set true if we are upset
2182 for (Dependencies::DepStream deps(this); deps.next(); ) {
2183 // Evaluate only relevant dependencies.
2184 if (deps.spot_check_dependency_at(changes) != NULL) {
2185 found_check = true;
2186 NOT_DEBUG(break);
2187 }
2188 }
2189 return found_check;
2190 }
2191
2192 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2193 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2194 Array<Method*>* dependee_methods = dependee_ik->methods();
2195 for (Dependencies::DepStream deps(this); deps.next(); ) {
2196 if (deps.type() == Dependencies::evol_method) {
2197 Method* method = deps.method_argument(0);
2198 for (int j = 0; j < dependee_methods->length(); j++) {
2199 if (dependee_methods->at(j) == method) {
2200 // RC_TRACE macro has an embedded ResourceMark
2201 RC_TRACE(0x01000000,
2202 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2203 _method->method_holder()->external_name(),
2204 _method->name()->as_C_string(),
2205 _method->signature()->as_C_string(), compile_id(),
2206 method->method_holder()->external_name(),
2207 method->name()->as_C_string(),
2208 method->signature()->as_C_string()));
2209 if (TraceDependencies || LogCompilation)
2210 deps.log_dependency(dependee);
2211 return true;
2212 }
2213 }
2214 }
2215 }
2216 return false;
2217 }
2218
2219 // Called from mark_for_deoptimization, when dependee is invalidated.
2220 bool nmethod::is_dependent_on_method(Method* dependee) {
2221 for (Dependencies::DepStream deps(this); deps.next(); ) {
2222 if (deps.type() != Dependencies::evol_method)
2223 continue;
2224 Method* method = deps.method_argument(0);
2225 if (method == dependee) return true;
2226 }
2227 return false;
2228 }
2229
2230
2231 bool nmethod::is_patchable_at(address instr_addr) {
2232 assert(insts_contains(instr_addr), "wrong nmethod used");
2233 if (is_zombie()) {
2234 // a zombie may never be patched
2235 return false;
2236 }
2237 return true;
2238 }
2239
2240
2241 address nmethod::continuation_for_implicit_exception(address pc) {
2242 // Exception happened outside inline-cache check code => we are inside
2243 // an active nmethod => use cpc to determine a return address
2244 int exception_offset = pc - code_begin();
2245 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2246 #ifdef ASSERT
2247 if (cont_offset == 0) {
2248 Thread* thread = ThreadLocalStorage::get_thread_slow();
2249 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2250 HandleMark hm(thread);
2251 ResourceMark rm(thread);
2252 CodeBlob* cb = CodeCache::find_blob(pc);
2253 assert(cb != NULL && cb == this, "");
2254 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2255 print();
2256 method()->print_codes();
2257 print_code();
2258 print_pcs();
2259 }
2260 #endif
2261 if (cont_offset == 0) {
2262 // Let the normal error handling report the exception
2263 return NULL;
2264 }
2265 return code_begin() + cont_offset;
2266 }
2267
2268
2269
2270 void nmethod_init() {
2271 // make sure you didn't forget to adjust the filler fields
2272 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2273 }
2274
2275
2276 //-------------------------------------------------------------------------------------------
2277
2278
2279 // QQQ might we make this work from a frame??
2280 nmethodLocker::nmethodLocker(address pc) {
2281 CodeBlob* cb = CodeCache::find_blob(pc);
2282 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2283 _nm = (nmethod*)cb;
2284 lock_nmethod(_nm);
2285 }
2286
2287 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2288 // should pass zombie_ok == true.
2289 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2290 if (nm == NULL) return;
2291 Atomic::inc(&nm->_lock_count);
2292 guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2293 }
2294
2295 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2296 if (nm == NULL) return;
2297 Atomic::dec(&nm->_lock_count);
2298 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2299 }
2300
2301
2302 // -----------------------------------------------------------------------------
2303 // nmethod::get_deopt_original_pc
2304 //
2305 // Return the original PC for the given PC if:
2306 // (a) the given PC belongs to a nmethod and
2307 // (b) it is a deopt PC
2308 address nmethod::get_deopt_original_pc(const frame* fr) {
2309 if (fr->cb() == NULL) return NULL;
2310
2311 nmethod* nm = fr->cb()->as_nmethod_or_null();
2312 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2313 return nm->get_original_pc(fr);
2314
2315 return NULL;
2316 }
2317
2318
2319 // -----------------------------------------------------------------------------
2320 // MethodHandle
2321
2322 bool nmethod::is_method_handle_return(address return_pc) {
2323 if (!has_method_handle_invokes()) return false;
2324 PcDesc* pd = pc_desc_at(return_pc);
2325 if (pd == NULL)
2326 return false;
2327 return pd->is_method_handle_invoke();
2328 }
2329
2330
2331 // -----------------------------------------------------------------------------
2332 // Verification
2333
2334 class VerifyOopsClosure: public OopClosure {
2335 nmethod* _nm;
2336 bool _ok;
2337 public:
2338 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2339 bool ok() { return _ok; }
2340 virtual void do_oop(oop* p) {
2341 if ((*p) == NULL || (*p)->is_oop()) return;
2342 if (_ok) {
2343 _nm->print_nmethod(true);
2344 _ok = false;
2345 }
2346 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2347 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2348 }
2349 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2350 };
2351
2352 void nmethod::verify() {
2353
2354 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2355 // seems odd.
2356
2357 if( is_zombie() || is_not_entrant() )
2358 return;
2359
2360 // Make sure all the entry points are correctly aligned for patching.
2361 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2362
2363 // assert(method()->is_oop(), "must be valid");
2364
2365 ResourceMark rm;
2366
2367 if (!CodeCache::contains_nmethod(this)) {
2368 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2369 }
2370
2371 if(is_native_method() )
2372 return;
2373
2374 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2375 if (nm != this) {
2376 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2377 this));
2378 }
2379
2380 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2381 if (! p->verify(this)) {
2382 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2383 }
2384 }
2385
2386 VerifyOopsClosure voc(this);
2387 oops_do(&voc);
2388 assert(voc.ok(), "embedded oops must be OK");
2389 verify_scavenge_root_oops();
2390
2391 verify_scopes();
2392 }
2393
2394
2395 void nmethod::verify_interrupt_point(address call_site) {
2396 // Verify IC only when nmethod installation is finished.
2397 bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed
2398 || !this->is_in_use(); // nmethod is installed, but not in 'in_use' state
2399 if (is_installed) {
2400 Thread *cur = Thread::current();
2401 if (CompiledIC_lock->owner() == cur ||
2402 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2403 SafepointSynchronize::is_at_safepoint())) {
2404 CompiledIC_at(this, call_site);
2405 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2406 } else {
2407 MutexLocker ml_verify (CompiledIC_lock);
2408 CompiledIC_at(this, call_site);
2409 }
2410 }
2411
2412 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2413 assert(pd != NULL, "PcDesc must exist");
2414 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2415 pd->obj_decode_offset(), pd->should_reexecute(),
2416 pd->return_oop());
2417 !sd->is_top(); sd = sd->sender()) {
2418 sd->verify();
2419 }
2420 }
2421
2422 void nmethod::verify_scopes() {
2423 if( !method() ) return; // Runtime stubs have no scope
2424 if (method()->is_native()) return; // Ignore stub methods.
2425 // iterate through all interrupt point
2426 // and verify the debug information is valid.
2427 RelocIterator iter((nmethod*)this);
2428 while (iter.next()) {
2429 address stub = NULL;
2430 switch (iter.type()) {
2431 case relocInfo::virtual_call_type:
2432 verify_interrupt_point(iter.addr());
2433 break;
2434 case relocInfo::opt_virtual_call_type:
2435 stub = iter.opt_virtual_call_reloc()->static_stub();
2436 verify_interrupt_point(iter.addr());
2437 break;
2438 case relocInfo::static_call_type:
2439 stub = iter.static_call_reloc()->static_stub();
2440 //verify_interrupt_point(iter.addr());
2441 break;
2442 case relocInfo::runtime_call_type:
2443 address destination = iter.reloc()->value();
2444 // Right now there is no way to find out which entries support
2445 // an interrupt point. It would be nice if we had this
2446 // information in a table.
2447 break;
2448 }
2449 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2450 }
2451 }
2452
2453
2454 // -----------------------------------------------------------------------------
2455 // Non-product code
2456 #ifndef PRODUCT
2457
2458 class DebugScavengeRoot: public OopClosure {
2459 nmethod* _nm;
2460 bool _ok;
2461 public:
2462 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2463 bool ok() { return _ok; }
2464 virtual void do_oop(oop* p) {
2465 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2466 if (_ok) {
2467 _nm->print_nmethod(true);
2468 _ok = false;
2469 }
2470 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2471 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2472 (*p)->print();
2473 }
2474 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2475 };
2476
2477 void nmethod::verify_scavenge_root_oops() {
2478 if (!on_scavenge_root_list()) {
2479 // Actually look inside, to verify the claim that it's clean.
2480 DebugScavengeRoot debug_scavenge_root(this);
2481 oops_do(&debug_scavenge_root);
2482 if (!debug_scavenge_root.ok())
2483 fatal("found an unadvertised bad scavengable oop in the code cache");
2484 }
2485 assert(scavenge_root_not_marked(), "");
2486 }
2487
2488 #endif // PRODUCT
2489
2490 // Printing operations
2491
2492 void nmethod::print() const {
2493 ResourceMark rm;
2494 ttyLocker ttyl; // keep the following output all in one block
2495
2496 tty->print("Compiled method ");
2497
2498 if (is_compiled_by_c1()) {
2499 tty->print("(c1) ");
2500 } else if (is_compiled_by_c2()) {
2501 tty->print("(c2) ");
2502 } else if (is_compiled_by_shark()) {
2503 tty->print("(shark) ");
2504 } else {
2505 tty->print("(nm) ");
2506 }
2507
2508 print_on(tty, NULL);
2509
2510 if (WizardMode) {
2511 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2512 tty->print(" for method " INTPTR_FORMAT , (address)method());
2513 tty->print(" { ");
2514 if (is_in_use()) tty->print("in_use ");
2515 if (is_not_entrant()) tty->print("not_entrant ");
2516 if (is_zombie()) tty->print("zombie ");
2517 if (is_unloaded()) tty->print("unloaded ");
2518 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2519 tty->print_cr("}:");
2520 }
2521 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2522 (address)this,
2523 (address)this + size(),
2524 size());
2525 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2526 relocation_begin(),
2527 relocation_end(),
2528 relocation_size());
2529 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2530 consts_begin(),
2531 consts_end(),
2532 consts_size());
2533 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2534 insts_begin(),
2535 insts_end(),
2536 insts_size());
2537 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2538 stub_begin(),
2539 stub_end(),
2540 stub_size());
2541 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2542 oops_begin(),
2543 oops_end(),
2544 oops_size());
2545 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2546 metadata_begin(),
2547 metadata_end(),
2548 metadata_size());
2549 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2550 scopes_data_begin(),
2551 scopes_data_end(),
2552 scopes_data_size());
2553 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2554 scopes_pcs_begin(),
2555 scopes_pcs_end(),
2556 scopes_pcs_size());
2557 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2558 dependencies_begin(),
2559 dependencies_end(),
2560 dependencies_size());
2561 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2562 handler_table_begin(),
2563 handler_table_end(),
2564 handler_table_size());
2565 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2566 nul_chk_table_begin(),
2567 nul_chk_table_end(),
2568 nul_chk_table_size());
2569 }
2570
2571 void nmethod::print_code() {
2572 HandleMark hm;
2573 ResourceMark m;
2574 Disassembler::decode(this);
2575 }
2576
2577
2578 #ifndef PRODUCT
2579
2580 void nmethod::print_scopes() {
2581 // Find the first pc desc for all scopes in the code and print it.
2582 ResourceMark rm;
2583 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2584 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2585 continue;
2586
2587 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2588 sd->print_on(tty, p);
2589 }
2590 }
2591
2592 void nmethod::print_dependencies() {
2593 ResourceMark rm;
2594 ttyLocker ttyl; // keep the following output all in one block
2595 tty->print_cr("Dependencies:");
2596 for (Dependencies::DepStream deps(this); deps.next(); ) {
2597 deps.print_dependency();
2598 Klass* ctxk = deps.context_type();
2599 if (ctxk != NULL) {
2600 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2601 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2602 }
2603 }
2604 deps.log_dependency(); // put it into the xml log also
2605 }
2606 }
2607
2608
2609 void nmethod::print_relocations() {
2610 ResourceMark m; // in case methods get printed via the debugger
2611 tty->print_cr("relocations:");
2612 RelocIterator iter(this);
2613 iter.print();
2614 if (UseRelocIndex) {
2615 jint* index_end = (jint*)relocation_end() - 1;
2616 jint index_size = *index_end;
2617 jint* index_start = (jint*)( (address)index_end - index_size );
2618 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2619 if (index_size > 0) {
2620 jint* ip;
2621 for (ip = index_start; ip+2 <= index_end; ip += 2)
2622 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2623 ip[0],
2624 ip[1],
2625 header_end()+ip[0],
2626 relocation_begin()-1+ip[1]);
2627 for (; ip < index_end; ip++)
2628 tty->print_cr(" (%d ?)", ip[0]);
2629 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip);
2630 ip++;
2631 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2632 }
2633 }
2634 }
2635
2636
2637 void nmethod::print_pcs() {
2638 ResourceMark m; // in case methods get printed via debugger
2639 tty->print_cr("pc-bytecode offsets:");
2640 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2641 p->print(this);
2642 }
2643 }
2644
2645 #endif // PRODUCT
2646
2647 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2648 RelocIterator iter(this, begin, end);
2649 bool have_one = false;
2650 while (iter.next()) {
2651 have_one = true;
2652 switch (iter.type()) {
2653 case relocInfo::none: return "no_reloc";
2654 case relocInfo::oop_type: {
2655 stringStream st;
2656 oop_Relocation* r = iter.oop_reloc();
2657 oop obj = r->oop_value();
2658 st.print("oop(");
2659 if (obj == NULL) st.print("NULL");
2660 else obj->print_value_on(&st);
2661 st.print(")");
2662 return st.as_string();
2663 }
2664 case relocInfo::metadata_type: {
2665 stringStream st;
2666 metadata_Relocation* r = iter.metadata_reloc();
2667 Metadata* obj = r->metadata_value();
2668 st.print("metadata(");
2669 if (obj == NULL) st.print("NULL");
2670 else obj->print_value_on(&st);
2671 st.print(")");
2672 return st.as_string();
2673 }
2674 case relocInfo::virtual_call_type: return "virtual_call";
2675 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2676 case relocInfo::static_call_type: return "static_call";
2677 case relocInfo::static_stub_type: return "static_stub";
2678 case relocInfo::runtime_call_type: return "runtime_call";
2679 case relocInfo::external_word_type: return "external_word";
2680 case relocInfo::internal_word_type: return "internal_word";
2681 case relocInfo::section_word_type: return "section_word";
2682 case relocInfo::poll_type: return "poll";
2683 case relocInfo::poll_return_type: return "poll_return";
2684 case relocInfo::type_mask: return "type_bit_mask";
2685 }
2686 }
2687 return have_one ? "other" : NULL;
2688 }
2689
2690 // Return a the last scope in (begin..end]
2691 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2692 PcDesc* p = pc_desc_near(begin+1);
2693 if (p != NULL && p->real_pc(this) <= end) {
2694 return new ScopeDesc(this, p->scope_decode_offset(),
2695 p->obj_decode_offset(), p->should_reexecute(),
2696 p->return_oop());
2697 }
2698 return NULL;
2699 }
2700
2701 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2702 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2703 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2704 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2705 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2706 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2707
2708 if (has_method_handle_invokes())
2709 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
2710
2711 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
2712
2713 if (block_begin == entry_point()) {
2714 methodHandle m = method();
2715 if (m.not_null()) {
2716 stream->print(" # ");
2717 m->print_value_on(stream);
2718 stream->cr();
2719 }
2720 if (m.not_null() && !is_osr_method()) {
2721 ResourceMark rm;
2722 int sizeargs = m->size_of_parameters();
2723 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2724 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2725 {
2726 int sig_index = 0;
2727 if (!m->is_static())
2728 sig_bt[sig_index++] = T_OBJECT; // 'this'
2729 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2730 BasicType t = ss.type();
2731 sig_bt[sig_index++] = t;
2732 if (type2size[t] == 2) {
2733 sig_bt[sig_index++] = T_VOID;
2734 } else {
2735 assert(type2size[t] == 1, "size is 1 or 2");
2736 }
2737 }
2738 assert(sig_index == sizeargs, "");
2739 }
2740 const char* spname = "sp"; // make arch-specific?
2741 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2742 int stack_slot_offset = this->frame_size() * wordSize;
2743 int tab1 = 14, tab2 = 24;
2744 int sig_index = 0;
2745 int arg_index = (m->is_static() ? 0 : -1);
2746 bool did_old_sp = false;
2747 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2748 bool at_this = (arg_index == -1);
2749 bool at_old_sp = false;
2750 BasicType t = (at_this ? T_OBJECT : ss.type());
2751 assert(t == sig_bt[sig_index], "sigs in sync");
2752 if (at_this)
2753 stream->print(" # this: ");
2754 else
2755 stream->print(" # parm%d: ", arg_index);
2756 stream->move_to(tab1);
2757 VMReg fst = regs[sig_index].first();
2758 VMReg snd = regs[sig_index].second();
2759 if (fst->is_reg()) {
2760 stream->print("%s", fst->name());
2761 if (snd->is_valid()) {
2762 stream->print(":%s", snd->name());
2763 }
2764 } else if (fst->is_stack()) {
2765 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2766 if (offset == stack_slot_offset) at_old_sp = true;
2767 stream->print("[%s+0x%x]", spname, offset);
2768 } else {
2769 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2770 }
2771 stream->print(" ");
2772 stream->move_to(tab2);
2773 stream->print("= ");
2774 if (at_this) {
2775 m->method_holder()->print_value_on(stream);
2776 } else {
2777 bool did_name = false;
2778 if (!at_this && ss.is_object()) {
2779 Symbol* name = ss.as_symbol_or_null();
2780 if (name != NULL) {
2781 name->print_value_on(stream);
2782 did_name = true;
2783 }
2784 }
2785 if (!did_name)
2786 stream->print("%s", type2name(t));
2787 }
2788 if (at_old_sp) {
2789 stream->print(" (%s of caller)", spname);
2790 did_old_sp = true;
2791 }
2792 stream->cr();
2793 sig_index += type2size[t];
2794 arg_index += 1;
2795 if (!at_this) ss.next();
2796 }
2797 if (!did_old_sp) {
2798 stream->print(" # ");
2799 stream->move_to(tab1);
2800 stream->print("[%s+0x%x]", spname, stack_slot_offset);
2801 stream->print(" (%s of caller)", spname);
2802 stream->cr();
2803 }
2804 }
2805 }
2806 }
2807
2808 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2809 // First, find an oopmap in (begin, end].
2810 // We use the odd half-closed interval so that oop maps and scope descs
2811 // which are tied to the byte after a call are printed with the call itself.
2812 address base = code_begin();
2813 OopMapSet* oms = oop_maps();
2814 if (oms != NULL) {
2815 for (int i = 0, imax = oms->size(); i < imax; i++) {
2816 OopMap* om = oms->at(i);
2817 address pc = base + om->offset();
2818 if (pc > begin) {
2819 if (pc <= end) {
2820 st->move_to(column);
2821 st->print("; ");
2822 om->print_on(st);
2823 }
2824 break;
2825 }
2826 }
2827 }
2828
2829 // Print any debug info present at this pc.
2830 ScopeDesc* sd = scope_desc_in(begin, end);
2831 if (sd != NULL) {
2832 st->move_to(column);
2833 if (sd->bci() == SynchronizationEntryBCI) {
2834 st->print(";*synchronization entry");
2835 } else {
2836 if (sd->method() == NULL) {
2837 st->print("method is NULL");
2838 } else if (sd->method()->is_native()) {
2839 st->print("method is native");
2840 } else {
2841 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2842 st->print(";*%s", Bytecodes::name(bc));
2843 switch (bc) {
2844 case Bytecodes::_invokevirtual:
2845 case Bytecodes::_invokespecial:
2846 case Bytecodes::_invokestatic:
2847 case Bytecodes::_invokeinterface:
2848 {
2849 Bytecode_invoke invoke(sd->method(), sd->bci());
2850 st->print(" ");
2851 if (invoke.name() != NULL)
2852 invoke.name()->print_symbol_on(st);
2853 else
2854 st->print("<UNKNOWN>");
2855 break;
2856 }
2857 case Bytecodes::_getfield:
2858 case Bytecodes::_putfield:
2859 case Bytecodes::_getstatic:
2860 case Bytecodes::_putstatic:
2861 {
2862 Bytecode_field field(sd->method(), sd->bci());
2863 st->print(" ");
2864 if (field.name() != NULL)
2865 field.name()->print_symbol_on(st);
2866 else
2867 st->print("<UNKNOWN>");
2868 }
2869 }
2870 }
2871 }
2872
2873 // Print all scopes
2874 for (;sd != NULL; sd = sd->sender()) {
2875 st->move_to(column);
2876 st->print("; -");
2877 if (sd->method() == NULL) {
2878 st->print("method is NULL");
2879 } else {
2880 sd->method()->print_short_name(st);
2881 }
2882 int lineno = sd->method()->line_number_from_bci(sd->bci());
2883 if (lineno != -1) {
2884 st->print("@%d (line %d)", sd->bci(), lineno);
2885 } else {
2886 st->print("@%d", sd->bci());
2887 }
2888 st->cr();
2889 }
2890 }
2891
2892 // Print relocation information
2893 const char* str = reloc_string_for(begin, end);
2894 if (str != NULL) {
2895 if (sd != NULL) st->cr();
2896 st->move_to(column);
2897 st->print("; {%s}", str);
2898 }
2899 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2900 if (cont_offset != 0) {
2901 st->move_to(column);
2902 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
2903 }
2904
2905 }
2906
2907 #ifndef PRODUCT
2908
2909 void nmethod::print_value_on(outputStream* st) const {
2910 st->print("nmethod");
2911 print_on(st, NULL);
2912 }
2913
2914 void nmethod::print_calls(outputStream* st) {
2915 RelocIterator iter(this);
2916 while (iter.next()) {
2917 switch (iter.type()) {
2918 case relocInfo::virtual_call_type:
2919 case relocInfo::opt_virtual_call_type: {
2920 VerifyMutexLocker mc(CompiledIC_lock);
2921 CompiledIC_at(iter.reloc())->print();
2922 break;
2923 }
2924 case relocInfo::static_call_type:
2925 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2926 compiledStaticCall_at(iter.reloc())->print();
2927 break;
2928 }
2929 }
2930 }
2931
2932 void nmethod::print_handler_table() {
2933 ExceptionHandlerTable(this).print();
2934 }
2935
2936 void nmethod::print_nul_chk_table() {
2937 ImplicitExceptionTable(this).print(code_begin());
2938 }
2939
2940 void nmethod::print_statistics() {
2941 ttyLocker ttyl;
2942 if (xtty != NULL) xtty->head("statistics type='nmethod'");
2943 nmethod_stats.print_native_nmethod_stats();
2944 nmethod_stats.print_nmethod_stats();
2945 DebugInformationRecorder::print_statistics();
2946 nmethod_stats.print_pc_stats();
2947 Dependencies::print_statistics();
2948 if (xtty != NULL) xtty->tail("statistics");
2949 }
2950
2951 #endif // PRODUCT