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) 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) 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)
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 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
754 CodeCache::add_scavenge_root_nmethod(this);
755 Universe::heap()->register_nmethod(this);
756 }
757 DEBUG_ONLY(verify_scavenge_root_oops();)
758 CodeCache::commit(this);
759 }
760
761 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
762 ttyLocker ttyl; // keep the following output all in one block
763 // This output goes directly to the tty, not the compiler log.
764 // To enable tools to match it up with the compilation activity,
765 // be sure to tag this tty output with the compile ID.
766 if (xtty != NULL) {
767 xtty->begin_head("print_dtrace_nmethod");
768 xtty->method(_method);
769 xtty->stamp();
770 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
771 }
772 // print the header part first
773 print();
774 // then print the requested information
775 if (PrintNMethods) {
776 print_code();
777 }
778 if (PrintRelocations) {
779 print_relocations();
780 }
781 if (xtty != NULL) {
782 xtty->tail("print_dtrace_nmethod");
783 }
784 }
785 }
786 #endif // def HAVE_DTRACE_H
787
788 void* nmethod::operator new(size_t size, int nmethod_size) throw() {
789 // Not critical, may return null if there is too little continuous memory
790 return CodeCache::allocate(nmethod_size);
791 }
792
793 nmethod::nmethod(
794 Method* method,
795 int nmethod_size,
796 int compile_id,
797 int entry_bci,
798 CodeOffsets* offsets,
799 int orig_pc_offset,
800 DebugInformationRecorder* debug_info,
801 Dependencies* dependencies,
802 CodeBuffer *code_buffer,
803 int frame_size,
804 OopMapSet* oop_maps,
805 ExceptionHandlerTable* handler_table,
806 ImplicitExceptionTable* nul_chk_table,
807 AbstractCompiler* compiler,
808 int comp_level
809 )
810 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
811 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
812 _native_receiver_sp_offset(in_ByteSize(-1)),
813 _native_basic_lock_sp_offset(in_ByteSize(-1))
814 {
815 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
816 {
817 debug_only(No_Safepoint_Verifier nsv;)
818 assert_locked_or_safepoint(CodeCache_lock);
819
820 init_defaults();
821 _method = method;
822 _entry_bci = entry_bci;
823 _compile_id = compile_id;
824 _comp_level = comp_level;
825 _compiler = compiler;
826 _orig_pc_offset = orig_pc_offset;
827 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
828
829 // Section offsets
830 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
831 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
832
833 // Exception handler and deopt handler are in the stub section
834 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
835 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
836 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
837 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
838 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
839 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
840 } else {
841 _deoptimize_mh_offset = -1;
842 }
843 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
844 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
845 } else {
846 _unwind_handler_offset = -1;
847 }
848
849 _oops_offset = data_offset();
850 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
851 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
852
853 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
854 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
855 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
856 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
857 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
858
859 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
860 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
861 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
862 _exception_cache = NULL;
863 _pc_desc_cache.reset_to(scopes_pcs_begin());
864
865 // Copy contents of ScopeDescRecorder to nmethod
866 code_buffer->copy_values_to(this);
867 debug_info->copy_to(this);
868 dependencies->copy_to(this);
869 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
870 CodeCache::add_scavenge_root_nmethod(this);
871 Universe::heap()->register_nmethod(this);
872 }
873 debug_only(verify_scavenge_root_oops());
874
875 CodeCache::commit(this);
876
877 // Copy contents of ExceptionHandlerTable to nmethod
878 handler_table->copy_to(this);
879 nul_chk_table->copy_to(this);
880
881 // we use the information of entry points to find out if a method is
882 // static or non static
883 assert(compiler->is_c2() ||
884 _method->is_static() == (entry_point() == _verified_entry_point),
885 " entry points must be same for static methods and vice versa");
886 }
887
888 bool printnmethods = PrintNMethods
889 || CompilerOracle::should_print(_method)
890 || CompilerOracle::has_option_string(_method, "PrintNMethods");
891 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
892 print_nmethod(printnmethods);
893 }
894 }
895
896
897 // Print a short set of xml attributes to identify this nmethod. The
898 // output should be embedded in some other element.
899 void nmethod::log_identity(xmlStream* log) const {
900 log->print(" compile_id='%d'", compile_id());
901 const char* nm_kind = compile_kind();
902 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
903 if (compiler() != NULL) {
904 log->print(" compiler='%s'", compiler()->name());
905 }
906 if (TieredCompilation) {
907 log->print(" level='%d'", comp_level());
908 }
909 }
910
911
912 #define LOG_OFFSET(log, name) \
913 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
914 log->print(" " XSTR(name) "_offset='%d'" , \
915 (intptr_t)name##_begin() - (intptr_t)this)
916
917
918 void nmethod::log_new_nmethod() const {
919 if (LogCompilation && xtty != NULL) {
920 ttyLocker ttyl;
921 HandleMark hm;
922 xtty->begin_elem("nmethod");
923 log_identity(xtty);
924 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
925 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
926
927 LOG_OFFSET(xtty, relocation);
928 LOG_OFFSET(xtty, consts);
929 LOG_OFFSET(xtty, insts);
930 LOG_OFFSET(xtty, stub);
931 LOG_OFFSET(xtty, scopes_data);
932 LOG_OFFSET(xtty, scopes_pcs);
933 LOG_OFFSET(xtty, dependencies);
934 LOG_OFFSET(xtty, handler_table);
935 LOG_OFFSET(xtty, nul_chk_table);
936 LOG_OFFSET(xtty, oops);
937
938 xtty->method(method());
939 xtty->stamp();
940 xtty->end_elem();
941 }
942 }
943
944 #undef LOG_OFFSET
945
946
947 // Print out more verbose output usually for a newly created nmethod.
948 void nmethod::print_on(outputStream* st, const char* msg) const {
949 if (st != NULL) {
950 ttyLocker ttyl;
951 if (WizardMode) {
952 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
953 st->print_cr(" (" INTPTR_FORMAT ")", this);
954 } else {
955 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
956 }
957 }
958 }
959
960
961 void nmethod::print_nmethod(bool printmethod) {
962 ttyLocker ttyl; // keep the following output all in one block
963 if (xtty != NULL) {
964 xtty->begin_head("print_nmethod");
965 xtty->stamp();
966 xtty->end_head();
967 }
968 // print the header part first
969 print();
970 // then print the requested information
971 if (printmethod) {
972 print_code();
973 print_pcs();
974 if (oop_maps()) {
975 oop_maps()->print();
976 }
977 }
978 if (PrintDebugInfo) {
979 print_scopes();
980 }
981 if (PrintRelocations) {
982 print_relocations();
983 }
984 if (PrintDependencies) {
985 print_dependencies();
986 }
987 if (PrintExceptionHandlers) {
988 print_handler_table();
989 print_nul_chk_table();
990 }
991 if (xtty != NULL) {
992 xtty->tail("print_nmethod");
993 }
994 }
995
996
997 // Promote one word from an assembly-time handle to a live embedded oop.
998 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
999 if (handle == NULL ||
1000 // As a special case, IC oops are initialized to 1 or -1.
1001 handle == (jobject) Universe::non_oop_word()) {
1002 (*dest) = (oop) handle;
1003 } else {
1004 (*dest) = JNIHandles::resolve_non_null(handle);
1005 }
1006 }
1007
1008
1009 // Have to have the same name because it's called by a template
1010 void nmethod::copy_values(GrowableArray<jobject>* array) {
1011 int length = array->length();
1012 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1013 oop* dest = oops_begin();
1014 for (int index = 0 ; index < length; index++) {
1015 initialize_immediate_oop(&dest[index], array->at(index));
1016 }
1017
1018 // Now we can fix up all the oops in the code. We need to do this
1019 // in the code because the assembler uses jobjects as placeholders.
1020 // The code and relocations have already been initialized by the
1021 // CodeBlob constructor, so it is valid even at this early point to
1022 // iterate over relocations and patch the code.
1023 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1024 }
1025
1026 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1027 int length = array->length();
1028 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1029 Metadata** dest = metadata_begin();
1030 for (int index = 0 ; index < length; index++) {
1031 dest[index] = array->at(index);
1032 }
1033 }
1034
1035 bool nmethod::is_at_poll_return(address pc) {
1036 RelocIterator iter(this, pc, pc+1);
1037 while (iter.next()) {
1038 if (iter.type() == relocInfo::poll_return_type)
1039 return true;
1040 }
1041 return false;
1042 }
1043
1044
1045 bool nmethod::is_at_poll_or_poll_return(address pc) {
1046 RelocIterator iter(this, pc, pc+1);
1047 while (iter.next()) {
1048 relocInfo::relocType t = iter.type();
1049 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1050 return true;
1051 }
1052 return false;
1053 }
1054
1055
1056 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1057 // re-patch all oop-bearing instructions, just in case some oops moved
1058 RelocIterator iter(this, begin, end);
1059 while (iter.next()) {
1060 if (iter.type() == relocInfo::oop_type) {
1061 oop_Relocation* reloc = iter.oop_reloc();
1062 if (initialize_immediates && reloc->oop_is_immediate()) {
1063 oop* dest = reloc->oop_addr();
1064 initialize_immediate_oop(dest, (jobject) *dest);
1065 }
1066 // Refresh the oop-related bits of this instruction.
1067 reloc->fix_oop_relocation();
1068 } else if (iter.type() == relocInfo::metadata_type) {
1069 metadata_Relocation* reloc = iter.metadata_reloc();
1070 reloc->fix_metadata_relocation();
1071 }
1072 }
1073 }
1074
1075
1076 void nmethod::verify_oop_relocations() {
1077 // Ensure sure that the code matches the current oop values
1078 RelocIterator iter(this, NULL, NULL);
1079 while (iter.next()) {
1080 if (iter.type() == relocInfo::oop_type) {
1081 oop_Relocation* reloc = iter.oop_reloc();
1082 if (!reloc->oop_is_immediate()) {
1083 reloc->verify_oop_relocation();
1084 }
1085 }
1086 }
1087 }
1088
1089
1090 ScopeDesc* nmethod::scope_desc_at(address pc) {
1091 PcDesc* pd = pc_desc_at(pc);
1092 guarantee(pd != NULL, "scope must be present");
1093 return new ScopeDesc(this, pd->scope_decode_offset(),
1094 pd->obj_decode_offset(), pd->should_reexecute(),
1095 pd->return_oop());
1096 }
1097
1098
1099 void nmethod::clear_inline_caches() {
1100 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1101 if (is_zombie()) {
1102 return;
1103 }
1104
1105 RelocIterator iter(this);
1106 while (iter.next()) {
1107 iter.reloc()->clear_inline_cache();
1108 }
1109 }
1110
1111
1112 void nmethod::cleanup_inline_caches() {
1113
1114 assert_locked_or_safepoint(CompiledIC_lock);
1115
1116 // If the method is not entrant or zombie then a JMP is plastered over the
1117 // first few bytes. If an oop in the old code was there, that oop
1118 // should not get GC'd. Skip the first few bytes of oops on
1119 // not-entrant methods.
1120 address low_boundary = verified_entry_point();
1121 if (!is_in_use()) {
1122 low_boundary += NativeJump::instruction_size;
1123 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1124 // This means that the low_boundary is going to be a little too high.
1125 // This shouldn't matter, since oops of non-entrant methods are never used.
1126 // In fact, why are we bothering to look at oops in a non-entrant method??
1127 }
1128
1129 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1130 ResourceMark rm;
1131 RelocIterator iter(this, low_boundary);
1132 while(iter.next()) {
1133 switch(iter.type()) {
1134 case relocInfo::virtual_call_type:
1135 case relocInfo::opt_virtual_call_type: {
1136 CompiledIC *ic = CompiledIC_at(iter.reloc());
1137 // Ok, to lookup references to zombies here
1138 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1139 if( cb != NULL && cb->is_nmethod() ) {
1140 nmethod* nm = (nmethod*)cb;
1141 // Clean inline caches pointing to both zombie and not_entrant methods
1142 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1143 }
1144 break;
1145 }
1146 case relocInfo::static_call_type: {
1147 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1148 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1149 if( cb != NULL && cb->is_nmethod() ) {
1150 nmethod* nm = (nmethod*)cb;
1151 // Clean inline caches pointing to both zombie and not_entrant methods
1152 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1153 }
1154 break;
1155 }
1156 }
1157 }
1158 }
1159
1160 // This is a private interface with the sweeper.
1161 void nmethod::mark_as_seen_on_stack() {
1162 assert(is_alive(), "Must be an alive method");
1163 // Set the traversal mark to ensure that the sweeper does 2
1164 // cleaning passes before moving to zombie.
1165 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1166 }
1167
1168 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1169 // there are no activations on the stack, not in use by the VM,
1170 // and not in use by the ServiceThread)
1171 bool nmethod::can_not_entrant_be_converted() {
1172 assert(is_not_entrant(), "must be a non-entrant method");
1173
1174 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1175 // count can be greater than the stack traversal count before it hits the
1176 // nmethod for the second time.
1177 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1178 !is_locked_by_vm();
1179 }
1180
1181 void nmethod::inc_decompile_count() {
1182 if (!is_compiled_by_c2()) return;
1183 // Could be gated by ProfileTraps, but do not bother...
1184 Method* m = method();
1185 if (m == NULL) return;
1186 MethodData* mdo = m->method_data();
1187 if (mdo == NULL) return;
1188 // There is a benign race here. See comments in methodData.hpp.
1189 mdo->inc_decompile_count();
1190 }
1191
1192 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1193
1194 post_compiled_method_unload();
1195
1196 // Since this nmethod is being unloaded, make sure that dependencies
1197 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1198 // indicate that this work is being done during a GC.
1199 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1200 assert(is_alive != NULL, "Should be non-NULL");
1201 // A non-NULL is_alive closure indicates that this is being called during GC.
1202 flush_dependencies(is_alive);
1203
1204 // Break cycle between nmethod & method
1205 if (TraceClassUnloading && WizardMode) {
1206 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1207 " unloadable], Method*(" INTPTR_FORMAT
1208 "), cause(" INTPTR_FORMAT ")",
1209 this, (address)_method, (address)cause);
1210 if (!Universe::heap()->is_gc_active())
1211 cause->klass()->print();
1212 }
1213 // Unlink the osr method, so we do not look this up again
1214 if (is_osr_method()) {
1215 invalidate_osr_method();
1216 }
1217 // If _method is already NULL the Method* is about to be unloaded,
1218 // so we don't have to break the cycle. Note that it is possible to
1219 // have the Method* live here, in case we unload the nmethod because
1220 // it is pointing to some oop (other than the Method*) being unloaded.
1221 if (_method != NULL) {
1222 // OSR methods point to the Method*, but the Method* does not
1223 // point back!
1224 if (_method->code() == this) {
1225 _method->clear_code(); // Break a cycle
1226 }
1227 _method = NULL; // Clear the method of this dead nmethod
1228 }
1229 // Make the class unloaded - i.e., change state and notify sweeper
1230 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1231 if (is_in_use()) {
1232 // Transitioning directly from live to unloaded -- so
1233 // we need to force a cache clean-up; remember this
1234 // for later on.
1235 CodeCache::set_needs_cache_clean(true);
1236 }
1237 _state = unloaded;
1238
1239 // Log the unloading.
1240 log_state_change();
1241
1242 // The Method* is gone at this point
1243 assert(_method == NULL, "Tautology");
1244
1245 set_osr_link(NULL);
1246 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1247 NMethodSweeper::report_state_change(this);
1248 }
1249
1250 void nmethod::invalidate_osr_method() {
1251 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1252 // Remove from list of active nmethods
1253 if (method() != NULL)
1254 method()->method_holder()->remove_osr_nmethod(this);
1255 // Set entry as invalid
1256 _entry_bci = InvalidOSREntryBci;
1257 }
1258
1259 void nmethod::log_state_change() const {
1260 if (LogCompilation) {
1261 if (xtty != NULL) {
1262 ttyLocker ttyl; // keep the following output all in one block
1263 if (_state == unloaded) {
1264 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1265 os::current_thread_id());
1266 } else {
1267 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1268 os::current_thread_id(),
1269 (_state == zombie ? " zombie='1'" : ""));
1270 }
1271 log_identity(xtty);
1272 xtty->stamp();
1273 xtty->end_elem();
1274 }
1275 }
1276 if (PrintCompilation && _state != unloaded) {
1277 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1278 }
1279 }
1280
1281 /**
1282 * Common functionality for both make_not_entrant and make_zombie
1283 */
1284 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1285 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1286 assert(!is_zombie(), "should not already be a zombie");
1287
1288 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1289 nmethodLocker nml(this);
1290 methodHandle the_method(method());
1291 No_Safepoint_Verifier nsv;
1292
1293 // during patching, depending on the nmethod state we must notify the GC that
1294 // code has been unloaded, unregistering it. We cannot do this right while
1295 // holding the Patching_lock because we need to use the CodeCache_lock. This
1296 // would be prone to deadlocks.
1297 // This flag is used to remember whether we need to later lock and unregister.
1298 bool nmethod_needs_unregister = false;
1299
1300 {
1301 // invalidate osr nmethod before acquiring the patching lock since
1302 // they both acquire leaf locks and we don't want a deadlock.
1303 // This logic is equivalent to the logic below for patching the
1304 // verified entry point of regular methods.
1305 if (is_osr_method()) {
1306 // this effectively makes the osr nmethod not entrant
1307 invalidate_osr_method();
1308 }
1309
1310 // Enter critical section. Does not block for safepoint.
1311 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1312
1313 if (_state == state) {
1314 // another thread already performed this transition so nothing
1315 // to do, but return false to indicate this.
1316 return false;
1317 }
1318
1319 // The caller can be calling the method statically or through an inline
1320 // cache call.
1321 if (!is_osr_method() && !is_not_entrant()) {
1322 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1323 SharedRuntime::get_handle_wrong_method_stub());
1324 }
1325
1326 if (is_in_use()) {
1327 // It's a true state change, so mark the method as decompiled.
1328 // Do it only for transition from alive.
1329 inc_decompile_count();
1330 }
1331
1332 // If the state is becoming a zombie, signal to unregister the nmethod with
1333 // the heap.
1334 // This nmethod may have already been unloaded during a full GC.
1335 if ((state == zombie) && !is_unloaded()) {
1336 nmethod_needs_unregister = true;
1337 }
1338
1339 // Must happen before state change. Otherwise we have a race condition in
1340 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1341 // transition its state from 'not_entrant' to 'zombie' without having to wait
1342 // for stack scanning.
1343 if (state == not_entrant) {
1344 mark_as_seen_on_stack();
1345 OrderAccess::storestore();
1346 }
1347
1348 // Change state
1349 _state = state;
1350
1351 // Log the transition once
1352 log_state_change();
1353
1354 // Remove nmethod from method.
1355 // We need to check if both the _code and _from_compiled_code_entry_point
1356 // refer to this nmethod because there is a race in setting these two fields
1357 // in Method* as seen in bugid 4947125.
1358 // If the vep() points to the zombie nmethod, the memory for the nmethod
1359 // could be flushed and the compiler and vtable stubs could still call
1360 // through it.
1361 if (method() != NULL && (method()->code() == this ||
1362 method()->from_compiled_entry() == verified_entry_point())) {
1363 HandleMark hm;
1364 method()->clear_code();
1365 }
1366 } // leave critical region under Patching_lock
1367
1368 // When the nmethod becomes zombie it is no longer alive so the
1369 // dependencies must be flushed. nmethods in the not_entrant
1370 // state will be flushed later when the transition to zombie
1371 // happens or they get unloaded.
1372 if (state == zombie) {
1373 {
1374 // Flushing dependecies must be done before any possible
1375 // safepoint can sneak in, otherwise the oops used by the
1376 // dependency logic could have become stale.
1377 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1378 if (nmethod_needs_unregister) {
1379 Universe::heap()->unregister_nmethod(this);
1380 }
1381 flush_dependencies(NULL);
1382 }
1383
1384 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1385 // event and it hasn't already been reported for this nmethod then
1386 // report it now. The event may have been reported earilier if the GC
1387 // marked it for unloading). JvmtiDeferredEventQueue support means
1388 // we no longer go to a safepoint here.
1389 post_compiled_method_unload();
1390
1391 #ifdef ASSERT
1392 // It's no longer safe to access the oops section since zombie
1393 // nmethods aren't scanned for GC.
1394 _oops_are_stale = true;
1395 #endif
1396 // the Method may be reclaimed by class unloading now that the
1397 // nmethod is in zombie state
1398 set_method(NULL);
1399 } else {
1400 assert(state == not_entrant, "other cases may need to be handled differently");
1401 }
1402
1403 if (TraceCreateZombies) {
1404 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1405 }
1406
1407 NMethodSweeper::report_state_change(this);
1408 return true;
1409 }
1410
1411 void nmethod::flush() {
1412 // Note that there are no valid oops in the nmethod anymore.
1413 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1414 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1415
1416 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1417 assert_locked_or_safepoint(CodeCache_lock);
1418
1419 // completely deallocate this method
1420 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1421 if (PrintMethodFlushing) {
1422 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1423 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
1424 }
1425
1426 // We need to deallocate any ExceptionCache data.
1427 // Note that we do not need to grab the nmethod lock for this, it
1428 // better be thread safe if we're disposing of it!
1429 ExceptionCache* ec = exception_cache();
1430 set_exception_cache(NULL);
1431 while(ec != NULL) {
1432 ExceptionCache* next = ec->next();
1433 delete ec;
1434 ec = next;
1435 }
1436
1437 if (on_scavenge_root_list()) {
1438 CodeCache::drop_scavenge_root_nmethod(this);
1439 }
1440
1441 #ifdef SHARK
1442 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1443 #endif // SHARK
1444
1445 ((CodeBlob*)(this))->flush();
1446
1447 CodeCache::free(this);
1448 }
1449
1450
1451 //
1452 // Notify all classes this nmethod is dependent on that it is no
1453 // longer dependent. This should only be called in two situations.
1454 // First, when a nmethod transitions to a zombie all dependents need
1455 // to be clear. Since zombification happens at a safepoint there's no
1456 // synchronization issues. The second place is a little more tricky.
1457 // During phase 1 of mark sweep class unloading may happen and as a
1458 // result some nmethods may get unloaded. In this case the flushing
1459 // of dependencies must happen during phase 1 since after GC any
1460 // dependencies in the unloaded nmethod won't be updated, so
1461 // traversing the dependency information in unsafe. In that case this
1462 // function is called with a non-NULL argument and this function only
1463 // notifies instanceKlasses that are reachable
1464
1465 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1466 assert_locked_or_safepoint(CodeCache_lock);
1467 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1468 "is_alive is non-NULL if and only if we are called during GC");
1469 if (!has_flushed_dependencies()) {
1470 set_has_flushed_dependencies();
1471 for (Dependencies::DepStream deps(this); deps.next(); ) {
1472 Klass* klass = deps.context_type();
1473 if (klass == NULL) continue; // ignore things like evol_method
1474
1475 // During GC the is_alive closure is non-NULL, and is used to
1476 // determine liveness of dependees that need to be updated.
1477 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1478 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1479 }
1480 }
1481 }
1482 }
1483
1484
1485 // If this oop is not live, the nmethod can be unloaded.
1486 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1487 assert(root != NULL, "just checking");
1488 oop obj = *root;
1489 if (obj == NULL || is_alive->do_object_b(obj)) {
1490 return false;
1491 }
1492
1493 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1494 // simply because one of its constant oops has gone dead.
1495 // No actual classes need to be unloaded in order for this to occur.
1496 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1497 make_unloaded(is_alive, obj);
1498 return true;
1499 }
1500
1501 // ------------------------------------------------------------------
1502 // post_compiled_method_load_event
1503 // new method for install_code() path
1504 // Transfer information from compilation to jvmti
1505 void nmethod::post_compiled_method_load_event() {
1506
1507 Method* moop = method();
1508 HOTSPOT_COMPILED_METHOD_LOAD(
1509 (char *) moop->klass_name()->bytes(),
1510 moop->klass_name()->utf8_length(),
1511 (char *) moop->name()->bytes(),
1512 moop->name()->utf8_length(),
1513 (char *) moop->signature()->bytes(),
1514 moop->signature()->utf8_length(),
1515 insts_begin(), insts_size());
1516
1517 if (JvmtiExport::should_post_compiled_method_load() ||
1518 JvmtiExport::should_post_compiled_method_unload()) {
1519 get_and_cache_jmethod_id();
1520 }
1521
1522 if (JvmtiExport::should_post_compiled_method_load()) {
1523 // Let the Service thread (which is a real Java thread) post the event
1524 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1525 JvmtiDeferredEventQueue::enqueue(
1526 JvmtiDeferredEvent::compiled_method_load_event(this));
1527 }
1528 }
1529
1530 jmethodID nmethod::get_and_cache_jmethod_id() {
1531 if (_jmethod_id == NULL) {
1532 // Cache the jmethod_id since it can no longer be looked up once the
1533 // method itself has been marked for unloading.
1534 _jmethod_id = method()->jmethod_id();
1535 }
1536 return _jmethod_id;
1537 }
1538
1539 void nmethod::post_compiled_method_unload() {
1540 if (unload_reported()) {
1541 // During unloading we transition to unloaded and then to zombie
1542 // and the unloading is reported during the first transition.
1543 return;
1544 }
1545
1546 assert(_method != NULL && !is_unloaded(), "just checking");
1547 DTRACE_METHOD_UNLOAD_PROBE(method());
1548
1549 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1550 // post the event. Sometime later this nmethod will be made a zombie
1551 // by the sweeper but the Method* will not be valid at that point.
1552 // If the _jmethod_id is null then no load event was ever requested
1553 // so don't bother posting the unload. The main reason for this is
1554 // that the jmethodID is a weak reference to the Method* so if
1555 // it's being unloaded there's no way to look it up since the weak
1556 // ref will have been cleared.
1557 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1558 assert(!unload_reported(), "already unloaded");
1559 JvmtiDeferredEvent event =
1560 JvmtiDeferredEvent::compiled_method_unload_event(this,
1561 _jmethod_id, insts_begin());
1562 if (SafepointSynchronize::is_at_safepoint()) {
1563 // Don't want to take the queueing lock. Add it as pending and
1564 // it will get enqueued later.
1565 JvmtiDeferredEventQueue::add_pending_event(event);
1566 } else {
1567 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1568 JvmtiDeferredEventQueue::enqueue(event);
1569 }
1570 }
1571
1572 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1573 // any time. As the nmethod is being unloaded now we mark it has
1574 // having the unload event reported - this will ensure that we don't
1575 // attempt to report the event in the unlikely scenario where the
1576 // event is enabled at the time the nmethod is made a zombie.
1577 set_unload_reported();
1578 }
1579
1580 // This is called at the end of the strong tracing/marking phase of a
1581 // GC to unload an nmethod if it contains otherwise unreachable
1582 // oops.
1583
1584 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1585 // Make sure the oop's ready to receive visitors
1586 assert(!is_zombie() && !is_unloaded(),
1587 "should not call follow on zombie or unloaded nmethod");
1588
1589 // If the method is not entrant then a JMP is plastered over the
1590 // first few bytes. If an oop in the old code was there, that oop
1591 // should not get GC'd. Skip the first few bytes of oops on
1592 // not-entrant methods.
1593 address low_boundary = verified_entry_point();
1594 if (is_not_entrant()) {
1595 low_boundary += NativeJump::instruction_size;
1596 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1597 // (See comment above.)
1598 }
1599
1600 // The RedefineClasses() API can cause the class unloading invariant
1601 // to no longer be true. See jvmtiExport.hpp for details.
1602 // Also, leave a debugging breadcrumb in local flag.
1603 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1604 if (a_class_was_redefined) {
1605 // This set of the unloading_occurred flag is done before the
1606 // call to post_compiled_method_unload() so that the unloading
1607 // of this nmethod is reported.
1608 unloading_occurred = true;
1609 }
1610
1611 // Exception cache
1612 ExceptionCache* ec = exception_cache();
1613 while (ec != NULL) {
1614 Klass* ex_klass = ec->exception_type();
1615 ExceptionCache* next_ec = ec->next();
1616 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
1617 remove_from_exception_cache(ec);
1618 }
1619 ec = next_ec;
1620 }
1621
1622 // If class unloading occurred we first iterate over all inline caches and
1623 // clear ICs where the cached oop is referring to an unloaded klass or method.
1624 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1625 // iteration below.
1626 if (unloading_occurred) {
1627 RelocIterator iter(this, low_boundary);
1628 while(iter.next()) {
1629 if (iter.type() == relocInfo::virtual_call_type) {
1630 CompiledIC *ic = CompiledIC_at(iter.reloc());
1631 if (ic->is_icholder_call()) {
1632 // The only exception is compiledICHolder oops which may
1633 // yet be marked below. (We check this further below).
1634 CompiledICHolder* cichk_oop = ic->cached_icholder();
1635 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1636 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1637 continue;
1638 }
1639 } else {
1640 Metadata* ic_oop = ic->cached_metadata();
1641 if (ic_oop != NULL) {
1642 if (ic_oop->is_klass()) {
1643 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1644 continue;
1645 }
1646 } else if (ic_oop->is_method()) {
1647 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1648 continue;
1649 }
1650 } else {
1651 ShouldNotReachHere();
1652 }
1653 }
1654 }
1655 ic->set_to_clean();
1656 }
1657 }
1658 }
1659
1660 // Compiled code
1661 {
1662 RelocIterator iter(this, low_boundary);
1663 while (iter.next()) {
1664 if (iter.type() == relocInfo::oop_type) {
1665 oop_Relocation* r = iter.oop_reloc();
1666 // In this loop, we must only traverse those oops directly embedded in
1667 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1668 assert(1 == (r->oop_is_immediate()) +
1669 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1670 "oop must be found in exactly one place");
1671 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1672 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1673 return;
1674 }
1675 }
1676 }
1677 }
1678 }
1679
1680
1681 // Scopes
1682 for (oop* p = oops_begin(); p < oops_end(); p++) {
1683 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1684 if (can_unload(is_alive, p, unloading_occurred)) {
1685 return;
1686 }
1687 }
1688
1689 // Ensure that all metadata is still alive
1690 verify_metadata_loaders(low_boundary, is_alive);
1691 }
1692
1693 #ifdef ASSERT
1694
1695 class CheckClass : AllStatic {
1696 static BoolObjectClosure* _is_alive;
1697
1698 // Check class_loader is alive for this bit of metadata.
1699 static void check_class(Metadata* md) {
1700 Klass* klass = NULL;
1701 if (md->is_klass()) {
1702 klass = ((Klass*)md);
1703 } else if (md->is_method()) {
1704 klass = ((Method*)md)->method_holder();
1705 } else if (md->is_methodData()) {
1706 klass = ((MethodData*)md)->method()->method_holder();
1707 } else {
1708 md->print();
1709 ShouldNotReachHere();
1710 }
1711 assert(klass->is_loader_alive(_is_alive), "must be alive");
1712 }
1713 public:
1714 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
1715 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
1716 _is_alive = is_alive;
1717 nm->metadata_do(check_class);
1718 }
1719 };
1720
1721 // This is called during a safepoint so can use static data
1722 BoolObjectClosure* CheckClass::_is_alive = NULL;
1723 #endif // ASSERT
1724
1725
1726 // Processing of oop references should have been sufficient to keep
1727 // all strong references alive. Any weak references should have been
1728 // cleared as well. Visit all the metadata and ensure that it's
1729 // really alive.
1730 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
1731 #ifdef ASSERT
1732 RelocIterator iter(this, low_boundary);
1733 while (iter.next()) {
1734 // static_stub_Relocations may have dangling references to
1735 // Method*s so trim them out here. Otherwise it looks like
1736 // compiled code is maintaining a link to dead metadata.
1737 address static_call_addr = NULL;
1738 if (iter.type() == relocInfo::opt_virtual_call_type) {
1739 CompiledIC* cic = CompiledIC_at(iter.reloc());
1740 if (!cic->is_call_to_interpreted()) {
1741 static_call_addr = iter.addr();
1742 }
1743 } else if (iter.type() == relocInfo::static_call_type) {
1744 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
1745 if (!csc->is_call_to_interpreted()) {
1746 static_call_addr = iter.addr();
1747 }
1748 }
1749 if (static_call_addr != NULL) {
1750 RelocIterator sciter(this, low_boundary);
1751 while (sciter.next()) {
1752 if (sciter.type() == relocInfo::static_stub_type &&
1753 sciter.static_stub_reloc()->static_call() == static_call_addr) {
1754 sciter.static_stub_reloc()->clear_inline_cache();
1755 }
1756 }
1757 }
1758 }
1759 // Check that the metadata embedded in the nmethod is alive
1760 CheckClass::do_check_class(is_alive, this);
1761 #endif
1762 }
1763
1764
1765 // Iterate over metadata calling this function. Used by RedefineClasses
1766 void nmethod::metadata_do(void f(Metadata*)) {
1767 address low_boundary = verified_entry_point();
1768 if (is_not_entrant()) {
1769 low_boundary += NativeJump::instruction_size;
1770 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1771 // (See comment above.)
1772 }
1773 {
1774 // Visit all immediate references that are embedded in the instruction stream.
1775 RelocIterator iter(this, low_boundary);
1776 while (iter.next()) {
1777 if (iter.type() == relocInfo::metadata_type ) {
1778 metadata_Relocation* r = iter.metadata_reloc();
1779 // In this lmetadata, we must only follow those metadatas directly embedded in
1780 // the code. Other metadatas (oop_index>0) are seen as part of
1781 // the metadata section below.
1782 assert(1 == (r->metadata_is_immediate()) +
1783 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1784 "metadata must be found in exactly one place");
1785 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1786 Metadata* md = r->metadata_value();
1787 f(md);
1788 }
1789 } else if (iter.type() == relocInfo::virtual_call_type) {
1790 // Check compiledIC holders associated with this nmethod
1791 CompiledIC *ic = CompiledIC_at(iter.reloc());
1792 if (ic->is_icholder_call()) {
1793 CompiledICHolder* cichk = ic->cached_icholder();
1794 f(cichk->holder_method());
1795 f(cichk->holder_klass());
1796 } else {
1797 Metadata* ic_oop = ic->cached_metadata();
1798 if (ic_oop != NULL) {
1799 f(ic_oop);
1800 }
1801 }
1802 }
1803 }
1804 }
1805
1806 // Visit the metadata section
1807 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1808 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
1809 Metadata* md = *p;
1810 f(md);
1811 }
1812
1813 // Call function Method*, not embedded in these other places.
1814 if (_method != NULL) f(_method);
1815 }
1816
1817 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1818 // make sure the oops ready to receive visitors
1819 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1820 assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1821
1822 // If the method is not entrant or zombie then a JMP is plastered over the
1823 // first few bytes. If an oop in the old code was there, that oop
1824 // should not get GC'd. Skip the first few bytes of oops on
1825 // not-entrant methods.
1826 address low_boundary = verified_entry_point();
1827 if (is_not_entrant()) {
1828 low_boundary += NativeJump::instruction_size;
1829 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1830 // (See comment above.)
1831 }
1832
1833 RelocIterator iter(this, low_boundary);
1834
1835 while (iter.next()) {
1836 if (iter.type() == relocInfo::oop_type ) {
1837 oop_Relocation* r = iter.oop_reloc();
1838 // In this loop, we must only follow those oops directly embedded in
1839 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1840 assert(1 == (r->oop_is_immediate()) +
1841 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1842 "oop must be found in exactly one place");
1843 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1844 f->do_oop(r->oop_addr());
1845 }
1846 }
1847 }
1848
1849 // Scopes
1850 // This includes oop constants not inlined in the code stream.
1851 for (oop* p = oops_begin(); p < oops_end(); p++) {
1852 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1853 f->do_oop(p);
1854 }
1855 }
1856
1857 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1858
1859 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1860
1861 // An nmethod is "marked" if its _mark_link is set non-null.
1862 // Even if it is the end of the linked list, it will have a non-null link value,
1863 // as long as it is on the list.
1864 // This code must be MP safe, because it is used from parallel GC passes.
1865 bool nmethod::test_set_oops_do_mark() {
1866 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1867 nmethod* observed_mark_link = _oops_do_mark_link;
1868 if (observed_mark_link == NULL) {
1869 // Claim this nmethod for this thread to mark.
1870 observed_mark_link = (nmethod*)
1871 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1872 if (observed_mark_link == NULL) {
1873
1874 // Atomically append this nmethod (now claimed) to the head of the list:
1875 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1876 for (;;) {
1877 nmethod* required_mark_nmethods = observed_mark_nmethods;
1878 _oops_do_mark_link = required_mark_nmethods;
1879 observed_mark_nmethods = (nmethod*)
1880 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1881 if (observed_mark_nmethods == required_mark_nmethods)
1882 break;
1883 }
1884 // Mark was clear when we first saw this guy.
1885 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
1886 return false;
1887 }
1888 }
1889 // On fall through, another racing thread marked this nmethod before we did.
1890 return true;
1891 }
1892
1893 void nmethod::oops_do_marking_prologue() {
1894 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
1895 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1896 // We use cmpxchg_ptr instead of regular assignment here because the user
1897 // may fork a bunch of threads, and we need them all to see the same state.
1898 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1899 guarantee(observed == NULL, "no races in this sequential code");
1900 }
1901
1902 void nmethod::oops_do_marking_epilogue() {
1903 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1904 nmethod* cur = _oops_do_mark_nmethods;
1905 while (cur != NMETHOD_SENTINEL) {
1906 assert(cur != NULL, "not NULL-terminated");
1907 nmethod* next = cur->_oops_do_mark_link;
1908 cur->_oops_do_mark_link = NULL;
1909 cur->fix_oop_relocations();
1910 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
1911 cur = next;
1912 }
1913 void* required = _oops_do_mark_nmethods;
1914 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1915 guarantee(observed == required, "no races in this sequential code");
1916 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
1917 }
1918
1919 class DetectScavengeRoot: public OopClosure {
1920 bool _detected_scavenge_root;
1921 public:
1922 DetectScavengeRoot() : _detected_scavenge_root(false)
1923 { NOT_PRODUCT(_print_nm = NULL); }
1924 bool detected_scavenge_root() { return _detected_scavenge_root; }
1925 virtual void do_oop(oop* p) {
1926 if ((*p) != NULL && (*p)->is_scavengable()) {
1927 NOT_PRODUCT(maybe_print(p));
1928 _detected_scavenge_root = true;
1929 }
1930 }
1931 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1932
1933 #ifndef PRODUCT
1934 nmethod* _print_nm;
1935 void maybe_print(oop* p) {
1936 if (_print_nm == NULL) return;
1937 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
1938 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
1939 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
1940 (void *)(*p), (intptr_t)p);
1941 (*p)->print();
1942 }
1943 #endif //PRODUCT
1944 };
1945
1946 bool nmethod::detect_scavenge_root_oops() {
1947 DetectScavengeRoot detect_scavenge_root;
1948 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
1949 oops_do(&detect_scavenge_root);
1950 return detect_scavenge_root.detected_scavenge_root();
1951 }
1952
1953 // Method that knows how to preserve outgoing arguments at call. This method must be
1954 // called with a frame corresponding to a Java invoke
1955 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1956 #ifndef SHARK
1957 if (!method()->is_native()) {
1958 SimpleScopeDesc ssd(this, fr.pc());
1959 Bytecode_invoke call(ssd.method(), ssd.bci());
1960 bool has_receiver = call.has_receiver();
1961 bool has_appendix = call.has_appendix();
1962 Symbol* signature = call.signature();
1963 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
1964 }
1965 #endif // !SHARK
1966 }
1967
1968
1969 oop nmethod::embeddedOop_at(u_char* p) {
1970 RelocIterator iter(this, p, p + 1);
1971 while (iter.next())
1972 if (iter.type() == relocInfo::oop_type) {
1973 return iter.oop_reloc()->oop_value();
1974 }
1975 return NULL;
1976 }
1977
1978
1979 inline bool includes(void* p, void* from, void* to) {
1980 return from <= p && p < to;
1981 }
1982
1983
1984 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1985 assert(count >= 2, "must be sentinel values, at least");
1986
1987 #ifdef ASSERT
1988 // must be sorted and unique; we do a binary search in find_pc_desc()
1989 int prev_offset = pcs[0].pc_offset();
1990 assert(prev_offset == PcDesc::lower_offset_limit,
1991 "must start with a sentinel");
1992 for (int i = 1; i < count; i++) {
1993 int this_offset = pcs[i].pc_offset();
1994 assert(this_offset > prev_offset, "offsets must be sorted");
1995 prev_offset = this_offset;
1996 }
1997 assert(prev_offset == PcDesc::upper_offset_limit,
1998 "must end with a sentinel");
1999 #endif //ASSERT
2000
2001 // Search for MethodHandle invokes and tag the nmethod.
2002 for (int i = 0; i < count; i++) {
2003 if (pcs[i].is_method_handle_invoke()) {
2004 set_has_method_handle_invokes(true);
2005 break;
2006 }
2007 }
2008 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2009
2010 int size = count * sizeof(PcDesc);
2011 assert(scopes_pcs_size() >= size, "oob");
2012 memcpy(scopes_pcs_begin(), pcs, size);
2013
2014 // Adjust the final sentinel downward.
2015 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2016 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2017 last_pc->set_pc_offset(content_size() + 1);
2018 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2019 // Fill any rounding gaps with copies of the last record.
2020 last_pc[1] = last_pc[0];
2021 }
2022 // The following assert could fail if sizeof(PcDesc) is not
2023 // an integral multiple of oopSize (the rounding term).
2024 // If it fails, change the logic to always allocate a multiple
2025 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2026 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2027 }
2028
2029 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2030 assert(scopes_data_size() >= size, "oob");
2031 memcpy(scopes_data_begin(), buffer, size);
2032 }
2033
2034
2035 #ifdef ASSERT
2036 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2037 PcDesc* lower = nm->scopes_pcs_begin();
2038 PcDesc* upper = nm->scopes_pcs_end();
2039 lower += 1; // exclude initial sentinel
2040 PcDesc* res = NULL;
2041 for (PcDesc* p = lower; p < upper; p++) {
2042 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2043 if (match_desc(p, pc_offset, approximate)) {
2044 if (res == NULL)
2045 res = p;
2046 else
2047 res = (PcDesc*) badAddress;
2048 }
2049 }
2050 return res;
2051 }
2052 #endif
2053
2054
2055 // Finds a PcDesc with real-pc equal to "pc"
2056 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2057 address base_address = code_begin();
2058 if ((pc < base_address) ||
2059 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2060 return NULL; // PC is wildly out of range
2061 }
2062 int pc_offset = (int) (pc - base_address);
2063
2064 // Check the PcDesc cache if it contains the desired PcDesc
2065 // (This as an almost 100% hit rate.)
2066 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2067 if (res != NULL) {
2068 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2069 return res;
2070 }
2071
2072 // Fallback algorithm: quasi-linear search for the PcDesc
2073 // Find the last pc_offset less than the given offset.
2074 // The successor must be the required match, if there is a match at all.
2075 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2076 PcDesc* lower = scopes_pcs_begin();
2077 PcDesc* upper = scopes_pcs_end();
2078 upper -= 1; // exclude final sentinel
2079 if (lower >= upper) return NULL; // native method; no PcDescs at all
2080
2081 #define assert_LU_OK \
2082 /* invariant on lower..upper during the following search: */ \
2083 assert(lower->pc_offset() < pc_offset, "sanity"); \
2084 assert(upper->pc_offset() >= pc_offset, "sanity")
2085 assert_LU_OK;
2086
2087 // Use the last successful return as a split point.
2088 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2089 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2090 if (mid->pc_offset() < pc_offset) {
2091 lower = mid;
2092 } else {
2093 upper = mid;
2094 }
2095
2096 // Take giant steps at first (4096, then 256, then 16, then 1)
2097 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2098 const int RADIX = (1 << LOG2_RADIX);
2099 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2100 while ((mid = lower + step) < upper) {
2101 assert_LU_OK;
2102 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2103 if (mid->pc_offset() < pc_offset) {
2104 lower = mid;
2105 } else {
2106 upper = mid;
2107 break;
2108 }
2109 }
2110 assert_LU_OK;
2111 }
2112
2113 // Sneak up on the value with a linear search of length ~16.
2114 while (true) {
2115 assert_LU_OK;
2116 mid = lower + 1;
2117 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2118 if (mid->pc_offset() < pc_offset) {
2119 lower = mid;
2120 } else {
2121 upper = mid;
2122 break;
2123 }
2124 }
2125 #undef assert_LU_OK
2126
2127 if (match_desc(upper, pc_offset, approximate)) {
2128 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2129 _pc_desc_cache.add_pc_desc(upper);
2130 return upper;
2131 } else {
2132 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2133 return NULL;
2134 }
2135 }
2136
2137
2138 void nmethod::check_all_dependencies(DepChange& changes) {
2139 // Checked dependencies are allocated into this ResourceMark
2140 ResourceMark rm;
2141
2142 // Turn off dependency tracing while actually testing dependencies.
2143 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
2144
2145 typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
2146 &DependencySignature::equals, 11027> DepTable;
2147
2148 DepTable* table = new DepTable();
2149
2150 // Iterate over live nmethods and check dependencies of all nmethods that are not
2151 // marked for deoptimization. A particular dependency is only checked once.
2152 for(nmethod* nm = CodeCache::alive_nmethod(CodeCache::first()); nm != NULL; nm = CodeCache::alive_nmethod(CodeCache::next(nm))) {
2153 if (!nm->is_marked_for_deoptimization()) {
2154 for (Dependencies::DepStream deps(nm); deps.next(); ) {
2155 // Construct abstraction of a dependency.
2156 DependencySignature* current_sig = new DependencySignature(deps);
2157
2158 // Determine if dependency is already checked. table->put(...) returns
2159 // 'true' if the dependency is added (i.e., was not in the hashtable).
2160 if (table->put(*current_sig, 1)) {
2161 if (deps.check_dependency() != NULL) {
2162 // Dependency checking failed. Print out information about the failed
2163 // dependency and finally fail with an assert. We can fail here, since
2164 // dependency checking is never done in a product build.
2165 changes.print();
2166 nm->print();
2167 nm->print_dependencies();
2168 assert(false, "Should have been marked for deoptimization");
2169 }
2170 }
2171 }
2172 }
2173 }
2174 }
2175
2176 bool nmethod::check_dependency_on(DepChange& changes) {
2177 // What has happened:
2178 // 1) a new class dependee has been added
2179 // 2) dependee and all its super classes have been marked
2180 bool found_check = false; // set true if we are upset
2181 for (Dependencies::DepStream deps(this); deps.next(); ) {
2182 // Evaluate only relevant dependencies.
2183 if (deps.spot_check_dependency_at(changes) != NULL) {
2184 found_check = true;
2185 NOT_DEBUG(break);
2186 }
2187 }
2188 return found_check;
2189 }
2190
2191 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2192 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2193 Array<Method*>* dependee_methods = dependee_ik->methods();
2194 for (Dependencies::DepStream deps(this); deps.next(); ) {
2195 if (deps.type() == Dependencies::evol_method) {
2196 Method* method = deps.method_argument(0);
2197 for (int j = 0; j < dependee_methods->length(); j++) {
2198 if (dependee_methods->at(j) == method) {
2199 // RC_TRACE macro has an embedded ResourceMark
2200 RC_TRACE(0x01000000,
2201 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2202 _method->method_holder()->external_name(),
2203 _method->name()->as_C_string(),
2204 _method->signature()->as_C_string(), compile_id(),
2205 method->method_holder()->external_name(),
2206 method->name()->as_C_string(),
2207 method->signature()->as_C_string()));
2208 if (TraceDependencies || LogCompilation)
2209 deps.log_dependency(dependee);
2210 return true;
2211 }
2212 }
2213 }
2214 }
2215 return false;
2216 }
2217
2218 // Called from mark_for_deoptimization, when dependee is invalidated.
2219 bool nmethod::is_dependent_on_method(Method* dependee) {
2220 for (Dependencies::DepStream deps(this); deps.next(); ) {
2221 if (deps.type() != Dependencies::evol_method)
2222 continue;
2223 Method* method = deps.method_argument(0);
2224 if (method == dependee) return true;
2225 }
2226 return false;
2227 }
2228
2229
2230 bool nmethod::is_patchable_at(address instr_addr) {
2231 assert(insts_contains(instr_addr), "wrong nmethod used");
2232 if (is_zombie()) {
2233 // a zombie may never be patched
2234 return false;
2235 }
2236 return true;
2237 }
2238
2239
2240 address nmethod::continuation_for_implicit_exception(address pc) {
2241 // Exception happened outside inline-cache check code => we are inside
2242 // an active nmethod => use cpc to determine a return address
2243 int exception_offset = pc - code_begin();
2244 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2245 #ifdef ASSERT
2246 if (cont_offset == 0) {
2247 Thread* thread = ThreadLocalStorage::get_thread_slow();
2248 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2249 HandleMark hm(thread);
2250 ResourceMark rm(thread);
2251 CodeBlob* cb = CodeCache::find_blob(pc);
2252 assert(cb != NULL && cb == this, "");
2253 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2254 print();
2255 method()->print_codes();
2256 print_code();
2257 print_pcs();
2258 }
2259 #endif
2260 if (cont_offset == 0) {
2261 // Let the normal error handling report the exception
2262 return NULL;
2263 }
2264 return code_begin() + cont_offset;
2265 }
2266
2267
2268
2269 void nmethod_init() {
2270 // make sure you didn't forget to adjust the filler fields
2271 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2272 }
2273
2274
2275 //-------------------------------------------------------------------------------------------
2276
2277
2278 // QQQ might we make this work from a frame??
2279 nmethodLocker::nmethodLocker(address pc) {
2280 CodeBlob* cb = CodeCache::find_blob(pc);
2281 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2282 _nm = (nmethod*)cb;
2283 lock_nmethod(_nm);
2284 }
2285
2286 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2287 // should pass zombie_ok == true.
2288 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2289 if (nm == NULL) return;
2290 Atomic::inc(&nm->_lock_count);
2291 assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2292 }
2293
2294 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2295 if (nm == NULL) return;
2296 Atomic::dec(&nm->_lock_count);
2297 assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2298 }
2299
2300
2301 // -----------------------------------------------------------------------------
2302 // nmethod::get_deopt_original_pc
2303 //
2304 // Return the original PC for the given PC if:
2305 // (a) the given PC belongs to a nmethod and
2306 // (b) it is a deopt PC
2307 address nmethod::get_deopt_original_pc(const frame* fr) {
2308 if (fr->cb() == NULL) return NULL;
2309
2310 nmethod* nm = fr->cb()->as_nmethod_or_null();
2311 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2312 return nm->get_original_pc(fr);
2313
2314 return NULL;
2315 }
2316
2317
2318 // -----------------------------------------------------------------------------
2319 // MethodHandle
2320
2321 bool nmethod::is_method_handle_return(address return_pc) {
2322 if (!has_method_handle_invokes()) return false;
2323 PcDesc* pd = pc_desc_at(return_pc);
2324 if (pd == NULL)
2325 return false;
2326 return pd->is_method_handle_invoke();
2327 }
2328
2329
2330 // -----------------------------------------------------------------------------
2331 // Verification
2332
2333 class VerifyOopsClosure: public OopClosure {
2334 nmethod* _nm;
2335 bool _ok;
2336 public:
2337 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2338 bool ok() { return _ok; }
2339 virtual void do_oop(oop* p) {
2340 if ((*p) == NULL || (*p)->is_oop()) return;
2341 if (_ok) {
2342 _nm->print_nmethod(true);
2343 _ok = false;
2344 }
2345 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2346 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2347 }
2348 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2349 };
2350
2351 void nmethod::verify() {
2352
2353 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2354 // seems odd.
2355
2356 if( is_zombie() || is_not_entrant() )
2357 return;
2358
2359 // Make sure all the entry points are correctly aligned for patching.
2360 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2361
2362 // assert(method()->is_oop(), "must be valid");
2363
2364 ResourceMark rm;
2365
2366 if (!CodeCache::contains(this)) {
2367 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2368 }
2369
2370 if(is_native_method() )
2371 return;
2372
2373 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2374 if (nm != this) {
2375 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2376 this));
2377 }
2378
2379 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2380 if (! p->verify(this)) {
2381 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2382 }
2383 }
2384
2385 VerifyOopsClosure voc(this);
2386 oops_do(&voc);
2387 assert(voc.ok(), "embedded oops must be OK");
2388 verify_scavenge_root_oops();
2389
2390 verify_scopes();
2391 }
2392
2393
2394 void nmethod::verify_interrupt_point(address call_site) {
2395 // Verify IC only when nmethod installation is finished.
2396 bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed
2397 || !this->is_in_use(); // nmethod is installed, but not in 'in_use' state
2398 if (is_installed) {
2399 Thread *cur = Thread::current();
2400 if (CompiledIC_lock->owner() == cur ||
2401 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2402 SafepointSynchronize::is_at_safepoint())) {
2403 CompiledIC_at(this, call_site);
2404 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2405 } else {
2406 MutexLocker ml_verify (CompiledIC_lock);
2407 CompiledIC_at(this, call_site);
2408 }
2409 }
2410
2411 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2412 assert(pd != NULL, "PcDesc must exist");
2413 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2414 pd->obj_decode_offset(), pd->should_reexecute(),
2415 pd->return_oop());
2416 !sd->is_top(); sd = sd->sender()) {
2417 sd->verify();
2418 }
2419 }
2420
2421 void nmethod::verify_scopes() {
2422 if( !method() ) return; // Runtime stubs have no scope
2423 if (method()->is_native()) return; // Ignore stub methods.
2424 // iterate through all interrupt point
2425 // and verify the debug information is valid.
2426 RelocIterator iter((nmethod*)this);
2427 while (iter.next()) {
2428 address stub = NULL;
2429 switch (iter.type()) {
2430 case relocInfo::virtual_call_type:
2431 verify_interrupt_point(iter.addr());
2432 break;
2433 case relocInfo::opt_virtual_call_type:
2434 stub = iter.opt_virtual_call_reloc()->static_stub();
2435 verify_interrupt_point(iter.addr());
2436 break;
2437 case relocInfo::static_call_type:
2438 stub = iter.static_call_reloc()->static_stub();
2439 //verify_interrupt_point(iter.addr());
2440 break;
2441 case relocInfo::runtime_call_type:
2442 address destination = iter.reloc()->value();
2443 // Right now there is no way to find out which entries support
2444 // an interrupt point. It would be nice if we had this
2445 // information in a table.
2446 break;
2447 }
2448 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2449 }
2450 }
2451
2452
2453 // -----------------------------------------------------------------------------
2454 // Non-product code
2455 #ifndef PRODUCT
2456
2457 class DebugScavengeRoot: public OopClosure {
2458 nmethod* _nm;
2459 bool _ok;
2460 public:
2461 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2462 bool ok() { return _ok; }
2463 virtual void do_oop(oop* p) {
2464 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2465 if (_ok) {
2466 _nm->print_nmethod(true);
2467 _ok = false;
2468 }
2469 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2470 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2471 (*p)->print();
2472 }
2473 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2474 };
2475
2476 void nmethod::verify_scavenge_root_oops() {
2477 if (!on_scavenge_root_list()) {
2478 // Actually look inside, to verify the claim that it's clean.
2479 DebugScavengeRoot debug_scavenge_root(this);
2480 oops_do(&debug_scavenge_root);
2481 if (!debug_scavenge_root.ok())
2482 fatal("found an unadvertised bad scavengable oop in the code cache");
2483 }
2484 assert(scavenge_root_not_marked(), "");
2485 }
2486
2487 #endif // PRODUCT
2488
2489 // Printing operations
2490
2491 void nmethod::print() const {
2492 ResourceMark rm;
2493 ttyLocker ttyl; // keep the following output all in one block
2494
2495 tty->print("Compiled method ");
2496
2497 if (is_compiled_by_c1()) {
2498 tty->print("(c1) ");
2499 } else if (is_compiled_by_c2()) {
2500 tty->print("(c2) ");
2501 } else if (is_compiled_by_shark()) {
2502 tty->print("(shark) ");
2503 } else {
2504 tty->print("(nm) ");
2505 }
2506
2507 print_on(tty, NULL);
2508
2509 if (WizardMode) {
2510 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2511 tty->print(" for method " INTPTR_FORMAT , (address)method());
2512 tty->print(" { ");
2513 if (is_in_use()) tty->print("in_use ");
2514 if (is_not_entrant()) tty->print("not_entrant ");
2515 if (is_zombie()) tty->print("zombie ");
2516 if (is_unloaded()) tty->print("unloaded ");
2517 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2518 tty->print_cr("}:");
2519 }
2520 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2521 (address)this,
2522 (address)this + size(),
2523 size());
2524 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2525 relocation_begin(),
2526 relocation_end(),
2527 relocation_size());
2528 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2529 consts_begin(),
2530 consts_end(),
2531 consts_size());
2532 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2533 insts_begin(),
2534 insts_end(),
2535 insts_size());
2536 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2537 stub_begin(),
2538 stub_end(),
2539 stub_size());
2540 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2541 oops_begin(),
2542 oops_end(),
2543 oops_size());
2544 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2545 metadata_begin(),
2546 metadata_end(),
2547 metadata_size());
2548 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2549 scopes_data_begin(),
2550 scopes_data_end(),
2551 scopes_data_size());
2552 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2553 scopes_pcs_begin(),
2554 scopes_pcs_end(),
2555 scopes_pcs_size());
2556 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2557 dependencies_begin(),
2558 dependencies_end(),
2559 dependencies_size());
2560 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2561 handler_table_begin(),
2562 handler_table_end(),
2563 handler_table_size());
2564 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2565 nul_chk_table_begin(),
2566 nul_chk_table_end(),
2567 nul_chk_table_size());
2568 }
2569
2570 void nmethod::print_code() {
2571 HandleMark hm;
2572 ResourceMark m;
2573 Disassembler::decode(this);
2574 }
2575
2576
2577 #ifndef PRODUCT
2578
2579 void nmethod::print_scopes() {
2580 // Find the first pc desc for all scopes in the code and print it.
2581 ResourceMark rm;
2582 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2583 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2584 continue;
2585
2586 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2587 sd->print_on(tty, p);
2588 }
2589 }
2590
2591 void nmethod::print_dependencies() {
2592 ResourceMark rm;
2593 ttyLocker ttyl; // keep the following output all in one block
2594 tty->print_cr("Dependencies:");
2595 for (Dependencies::DepStream deps(this); deps.next(); ) {
2596 deps.print_dependency();
2597 Klass* ctxk = deps.context_type();
2598 if (ctxk != NULL) {
2599 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2600 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2601 }
2602 }
2603 deps.log_dependency(); // put it into the xml log also
2604 }
2605 }
2606
2607
2608 void nmethod::print_relocations() {
2609 ResourceMark m; // in case methods get printed via the debugger
2610 tty->print_cr("relocations:");
2611 RelocIterator iter(this);
2612 iter.print();
2613 if (UseRelocIndex) {
2614 jint* index_end = (jint*)relocation_end() - 1;
2615 jint index_size = *index_end;
2616 jint* index_start = (jint*)( (address)index_end - index_size );
2617 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2618 if (index_size > 0) {
2619 jint* ip;
2620 for (ip = index_start; ip+2 <= index_end; ip += 2)
2621 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2622 ip[0],
2623 ip[1],
2624 header_end()+ip[0],
2625 relocation_begin()-1+ip[1]);
2626 for (; ip < index_end; ip++)
2627 tty->print_cr(" (%d ?)", ip[0]);
2628 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip);
2629 ip++;
2630 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2631 }
2632 }
2633 }
2634
2635
2636 void nmethod::print_pcs() {
2637 ResourceMark m; // in case methods get printed via debugger
2638 tty->print_cr("pc-bytecode offsets:");
2639 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2640 p->print(this);
2641 }
2642 }
2643
2644 #endif // PRODUCT
2645
2646 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2647 RelocIterator iter(this, begin, end);
2648 bool have_one = false;
2649 while (iter.next()) {
2650 have_one = true;
2651 switch (iter.type()) {
2652 case relocInfo::none: return "no_reloc";
2653 case relocInfo::oop_type: {
2654 stringStream st;
2655 oop_Relocation* r = iter.oop_reloc();
2656 oop obj = r->oop_value();
2657 st.print("oop(");
2658 if (obj == NULL) st.print("NULL");
2659 else obj->print_value_on(&st);
2660 st.print(")");
2661 return st.as_string();
2662 }
2663 case relocInfo::metadata_type: {
2664 stringStream st;
2665 metadata_Relocation* r = iter.metadata_reloc();
2666 Metadata* obj = r->metadata_value();
2667 st.print("metadata(");
2668 if (obj == NULL) st.print("NULL");
2669 else obj->print_value_on(&st);
2670 st.print(")");
2671 return st.as_string();
2672 }
2673 case relocInfo::virtual_call_type: return "virtual_call";
2674 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2675 case relocInfo::static_call_type: return "static_call";
2676 case relocInfo::static_stub_type: return "static_stub";
2677 case relocInfo::runtime_call_type: return "runtime_call";
2678 case relocInfo::external_word_type: return "external_word";
2679 case relocInfo::internal_word_type: return "internal_word";
2680 case relocInfo::section_word_type: return "section_word";
2681 case relocInfo::poll_type: return "poll";
2682 case relocInfo::poll_return_type: return "poll_return";
2683 case relocInfo::type_mask: return "type_bit_mask";
2684 }
2685 }
2686 return have_one ? "other" : NULL;
2687 }
2688
2689 // Return a the last scope in (begin..end]
2690 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2691 PcDesc* p = pc_desc_near(begin+1);
2692 if (p != NULL && p->real_pc(this) <= end) {
2693 return new ScopeDesc(this, p->scope_decode_offset(),
2694 p->obj_decode_offset(), p->should_reexecute(),
2695 p->return_oop());
2696 }
2697 return NULL;
2698 }
2699
2700 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2701 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2702 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2703 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2704 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2705 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2706
2707 if (has_method_handle_invokes())
2708 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
2709
2710 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
2711
2712 if (block_begin == entry_point()) {
2713 methodHandle m = method();
2714 if (m.not_null()) {
2715 stream->print(" # ");
2716 m->print_value_on(stream);
2717 stream->cr();
2718 }
2719 if (m.not_null() && !is_osr_method()) {
2720 ResourceMark rm;
2721 int sizeargs = m->size_of_parameters();
2722 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2723 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2724 {
2725 int sig_index = 0;
2726 if (!m->is_static())
2727 sig_bt[sig_index++] = T_OBJECT; // 'this'
2728 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2729 BasicType t = ss.type();
2730 sig_bt[sig_index++] = t;
2731 if (type2size[t] == 2) {
2732 sig_bt[sig_index++] = T_VOID;
2733 } else {
2734 assert(type2size[t] == 1, "size is 1 or 2");
2735 }
2736 }
2737 assert(sig_index == sizeargs, "");
2738 }
2739 const char* spname = "sp"; // make arch-specific?
2740 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2741 int stack_slot_offset = this->frame_size() * wordSize;
2742 int tab1 = 14, tab2 = 24;
2743 int sig_index = 0;
2744 int arg_index = (m->is_static() ? 0 : -1);
2745 bool did_old_sp = false;
2746 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2747 bool at_this = (arg_index == -1);
2748 bool at_old_sp = false;
2749 BasicType t = (at_this ? T_OBJECT : ss.type());
2750 assert(t == sig_bt[sig_index], "sigs in sync");
2751 if (at_this)
2752 stream->print(" # this: ");
2753 else
2754 stream->print(" # parm%d: ", arg_index);
2755 stream->move_to(tab1);
2756 VMReg fst = regs[sig_index].first();
2757 VMReg snd = regs[sig_index].second();
2758 if (fst->is_reg()) {
2759 stream->print("%s", fst->name());
2760 if (snd->is_valid()) {
2761 stream->print(":%s", snd->name());
2762 }
2763 } else if (fst->is_stack()) {
2764 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2765 if (offset == stack_slot_offset) at_old_sp = true;
2766 stream->print("[%s+0x%x]", spname, offset);
2767 } else {
2768 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2769 }
2770 stream->print(" ");
2771 stream->move_to(tab2);
2772 stream->print("= ");
2773 if (at_this) {
2774 m->method_holder()->print_value_on(stream);
2775 } else {
2776 bool did_name = false;
2777 if (!at_this && ss.is_object()) {
2778 Symbol* name = ss.as_symbol_or_null();
2779 if (name != NULL) {
2780 name->print_value_on(stream);
2781 did_name = true;
2782 }
2783 }
2784 if (!did_name)
2785 stream->print("%s", type2name(t));
2786 }
2787 if (at_old_sp) {
2788 stream->print(" (%s of caller)", spname);
2789 did_old_sp = true;
2790 }
2791 stream->cr();
2792 sig_index += type2size[t];
2793 arg_index += 1;
2794 if (!at_this) ss.next();
2795 }
2796 if (!did_old_sp) {
2797 stream->print(" # ");
2798 stream->move_to(tab1);
2799 stream->print("[%s+0x%x]", spname, stack_slot_offset);
2800 stream->print(" (%s of caller)", spname);
2801 stream->cr();
2802 }
2803 }
2804 }
2805 }
2806
2807 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2808 // First, find an oopmap in (begin, end].
2809 // We use the odd half-closed interval so that oop maps and scope descs
2810 // which are tied to the byte after a call are printed with the call itself.
2811 address base = code_begin();
2812 OopMapSet* oms = oop_maps();
2813 if (oms != NULL) {
2814 for (int i = 0, imax = oms->size(); i < imax; i++) {
2815 OopMap* om = oms->at(i);
2816 address pc = base + om->offset();
2817 if (pc > begin) {
2818 if (pc <= end) {
2819 st->move_to(column);
2820 st->print("; ");
2821 om->print_on(st);
2822 }
2823 break;
2824 }
2825 }
2826 }
2827
2828 // Print any debug info present at this pc.
2829 ScopeDesc* sd = scope_desc_in(begin, end);
2830 if (sd != NULL) {
2831 st->move_to(column);
2832 if (sd->bci() == SynchronizationEntryBCI) {
2833 st->print(";*synchronization entry");
2834 } else {
2835 if (sd->method() == NULL) {
2836 st->print("method is NULL");
2837 } else if (sd->method()->is_native()) {
2838 st->print("method is native");
2839 } else {
2840 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2841 st->print(";*%s", Bytecodes::name(bc));
2842 switch (bc) {
2843 case Bytecodes::_invokevirtual:
2844 case Bytecodes::_invokespecial:
2845 case Bytecodes::_invokestatic:
2846 case Bytecodes::_invokeinterface:
2847 {
2848 Bytecode_invoke invoke(sd->method(), sd->bci());
2849 st->print(" ");
2850 if (invoke.name() != NULL)
2851 invoke.name()->print_symbol_on(st);
2852 else
2853 st->print("<UNKNOWN>");
2854 break;
2855 }
2856 case Bytecodes::_getfield:
2857 case Bytecodes::_putfield:
2858 case Bytecodes::_getstatic:
2859 case Bytecodes::_putstatic:
2860 {
2861 Bytecode_field field(sd->method(), sd->bci());
2862 st->print(" ");
2863 if (field.name() != NULL)
2864 field.name()->print_symbol_on(st);
2865 else
2866 st->print("<UNKNOWN>");
2867 }
2868 }
2869 }
2870 }
2871
2872 // Print all scopes
2873 for (;sd != NULL; sd = sd->sender()) {
2874 st->move_to(column);
2875 st->print("; -");
2876 if (sd->method() == NULL) {
2877 st->print("method is NULL");
2878 } else {
2879 sd->method()->print_short_name(st);
2880 }
2881 int lineno = sd->method()->line_number_from_bci(sd->bci());
2882 if (lineno != -1) {
2883 st->print("@%d (line %d)", sd->bci(), lineno);
2884 } else {
2885 st->print("@%d", sd->bci());
2886 }
2887 st->cr();
2888 }
2889 }
2890
2891 // Print relocation information
2892 const char* str = reloc_string_for(begin, end);
2893 if (str != NULL) {
2894 if (sd != NULL) st->cr();
2895 st->move_to(column);
2896 st->print("; {%s}", str);
2897 }
2898 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2899 if (cont_offset != 0) {
2900 st->move_to(column);
2901 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
2902 }
2903
2904 }
2905
2906 #ifndef PRODUCT
2907
2908 void nmethod::print_value_on(outputStream* st) const {
2909 st->print("nmethod");
2910 print_on(st, NULL);
2911 }
2912
2913 void nmethod::print_calls(outputStream* st) {
2914 RelocIterator iter(this);
2915 while (iter.next()) {
2916 switch (iter.type()) {
2917 case relocInfo::virtual_call_type:
2918 case relocInfo::opt_virtual_call_type: {
2919 VerifyMutexLocker mc(CompiledIC_lock);
2920 CompiledIC_at(iter.reloc())->print();
2921 break;
2922 }
2923 case relocInfo::static_call_type:
2924 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2925 compiledStaticCall_at(iter.reloc())->print();
2926 break;
2927 }
2928 }
2929 }
2930
2931 void nmethod::print_handler_table() {
2932 ExceptionHandlerTable(this).print();
2933 }
2934
2935 void nmethod::print_nul_chk_table() {
2936 ImplicitExceptionTable(this).print(code_begin());
2937 }
2938
2939 void nmethod::print_statistics() {
2940 ttyLocker ttyl;
2941 if (xtty != NULL) xtty->head("statistics type='nmethod'");
2942 nmethod_stats.print_native_nmethod_stats();
2943 nmethod_stats.print_nmethod_stats();
2944 DebugInformationRecorder::print_statistics();
2945 nmethod_stats.print_pc_stats();
2946 Dependencies::print_statistics();
2947 if (xtty != NULL) xtty->tail("statistics");
2948 }
2949
2950 #endif // PRODUCT