1 /*
2 * Copyright (c) 1997, 2014, 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/atomic.inline.hpp"
41 #include "runtime/orderAccess.inline.hpp"
42 #include "runtime/sharedRuntime.hpp"
43 #include "runtime/sweeper.hpp"
44 #include "utilities/resourceHash.hpp"
45 #include "utilities/dtrace.hpp"
46 #include "utilities/events.hpp"
47 #include "utilities/xmlstream.hpp"
48 #ifdef SHARK
49 #include "shark/sharkCompiler.hpp"
50 #endif
51
52 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
53
54 unsigned char nmethod::_global_unloading_clock = 0;
55
56 #ifdef DTRACE_ENABLED
57
58 // Only bother with this argument setup if dtrace is available
59
60 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
61 { \
62 Method* m = (method); \
63 if (m != NULL) { \
64 Symbol* klass_name = m->klass_name(); \
65 Symbol* name = m->name(); \
66 Symbol* signature = m->signature(); \
67 HOTSPOT_COMPILED_METHOD_UNLOAD( \
68 (char *) klass_name->bytes(), klass_name->utf8_length(), \
69 (char *) name->bytes(), name->utf8_length(), \
70 (char *) signature->bytes(), signature->utf8_length()); \
71 } \
72 }
73
74 #else // ndef DTRACE_ENABLED
75
76 #define DTRACE_METHOD_UNLOAD_PROBE(method)
77
78 #endif
79
80 bool nmethod::is_compiled_by_c1() const {
81 if (compiler() == NULL) {
82 return false;
83 }
84 return compiler()->is_c1();
85 }
86 bool nmethod::is_compiled_by_c2() const {
87 if (compiler() == NULL) {
88 return false;
89 }
90 return compiler()->is_c2();
91 }
92 bool nmethod::is_compiled_by_shark() const {
93 if (compiler() == NULL) {
94 return false;
95 }
96 return compiler()->is_shark();
97 }
98
99
100
101 //---------------------------------------------------------------------------------
102 // NMethod statistics
103 // They are printed under various flags, including:
104 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
105 // (In the latter two cases, they like other stats are printed to the log only.)
106
107 #ifndef PRODUCT
108 // These variables are put into one block to reduce relocations
109 // and make it simpler to print from the debugger.
110 static
111 struct nmethod_stats_struct {
112 int nmethod_count;
113 int total_size;
114 int relocation_size;
115 int consts_size;
116 int insts_size;
117 int stub_size;
118 int scopes_data_size;
119 int scopes_pcs_size;
120 int dependencies_size;
121 int handler_table_size;
122 int nul_chk_table_size;
123 int oops_size;
124
125 void note_nmethod(nmethod* nm) {
126 nmethod_count += 1;
127 total_size += nm->size();
128 relocation_size += nm->relocation_size();
129 consts_size += nm->consts_size();
130 insts_size += nm->insts_size();
131 stub_size += nm->stub_size();
132 oops_size += nm->oops_size();
133 scopes_data_size += nm->scopes_data_size();
134 scopes_pcs_size += nm->scopes_pcs_size();
135 dependencies_size += nm->dependencies_size();
136 handler_table_size += nm->handler_table_size();
137 nul_chk_table_size += nm->nul_chk_table_size();
138 }
139 void print_nmethod_stats() {
140 if (nmethod_count == 0) return;
141 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
142 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
143 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
144 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
145 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size);
146 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
147 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
148 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
149 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
150 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
151 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
152 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
153 }
154
155 int native_nmethod_count;
156 int native_total_size;
157 int native_relocation_size;
158 int native_insts_size;
159 int native_oops_size;
160 void note_native_nmethod(nmethod* nm) {
161 native_nmethod_count += 1;
162 native_total_size += nm->size();
163 native_relocation_size += nm->relocation_size();
164 native_insts_size += nm->insts_size();
165 native_oops_size += nm->oops_size();
166 }
167 void print_native_nmethod_stats() {
168 if (native_nmethod_count == 0) return;
169 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
170 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
171 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
172 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size);
173 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
174 }
175
176 int pc_desc_resets; // number of resets (= number of caches)
177 int pc_desc_queries; // queries to nmethod::find_pc_desc
178 int pc_desc_approx; // number of those which have approximate true
179 int pc_desc_repeats; // number of _pc_descs[0] hits
180 int pc_desc_hits; // number of LRU cache hits
181 int pc_desc_tests; // total number of PcDesc examinations
182 int pc_desc_searches; // total number of quasi-binary search steps
183 int pc_desc_adds; // number of LUR cache insertions
184
185 void print_pc_stats() {
186 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
187 pc_desc_queries,
188 (double)(pc_desc_tests + pc_desc_searches)
189 / pc_desc_queries);
190 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
191 pc_desc_resets,
192 pc_desc_queries, pc_desc_approx,
193 pc_desc_repeats, pc_desc_hits,
194 pc_desc_tests, pc_desc_searches, pc_desc_adds);
195 }
196 } nmethod_stats;
197 #endif //PRODUCT
198
199
200 //---------------------------------------------------------------------------------
201
202
203 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
204 assert(pc != NULL, "Must be non null");
205 assert(exception.not_null(), "Must be non null");
206 assert(handler != NULL, "Must be non null");
207
208 _count = 0;
209 _exception_type = exception->klass();
210 _next = NULL;
211
212 add_address_and_handler(pc,handler);
213 }
214
215
216 address ExceptionCache::match(Handle exception, address pc) {
217 assert(pc != NULL,"Must be non null");
218 assert(exception.not_null(),"Must be non null");
219 if (exception->klass() == exception_type()) {
220 return (test_address(pc));
221 }
222
223 return NULL;
224 }
225
226
227 bool ExceptionCache::match_exception_with_space(Handle exception) {
228 assert(exception.not_null(),"Must be non null");
229 if (exception->klass() == exception_type() && count() < cache_size) {
230 return true;
231 }
232 return false;
233 }
234
235
236 address ExceptionCache::test_address(address addr) {
237 for (int i=0; i<count(); i++) {
238 if (pc_at(i) == addr) {
239 return handler_at(i);
240 }
241 }
242 return NULL;
243 }
244
245
246 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
247 if (test_address(addr) == handler) return true;
248 if (count() < cache_size) {
249 set_pc_at(count(),addr);
250 set_handler_at(count(), handler);
251 increment_count();
252 return true;
253 }
254 return false;
255 }
256
257
258 // private method for handling exception cache
259 // These methods are private, and used to manipulate the exception cache
260 // directly.
261 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
262 ExceptionCache* ec = exception_cache();
263 while (ec != NULL) {
264 if (ec->match_exception_with_space(exception)) {
265 return ec;
266 }
267 ec = ec->next();
268 }
269 return NULL;
270 }
271
272
273 //-----------------------------------------------------------------------------
274
275
276 // Helper used by both find_pc_desc methods.
277 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
278 NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
279 if (!approximate)
280 return pc->pc_offset() == pc_offset;
281 else
282 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
283 }
284
285 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
286 if (initial_pc_desc == NULL) {
287 _pc_descs[0] = NULL; // native method; no PcDescs at all
288 return;
289 }
290 NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
291 // reset the cache by filling it with benign (non-null) values
292 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
293 for (int i = 0; i < cache_size; i++)
294 _pc_descs[i] = initial_pc_desc;
295 }
296
297 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
298 NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
299 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
300
301 // Note: one might think that caching the most recently
302 // read value separately would be a win, but one would be
303 // wrong. When many threads are updating it, the cache
304 // line it's in would bounce between caches, negating
305 // any benefit.
306
307 // In order to prevent race conditions do not load cache elements
308 // repeatedly, but use a local copy:
309 PcDesc* res;
310
311 // Step one: Check the most recently added value.
312 res = _pc_descs[0];
313 if (res == NULL) return NULL; // native method; no PcDescs at all
314 if (match_desc(res, pc_offset, approximate)) {
315 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
316 return res;
317 }
318
319 // Step two: Check the rest of the LRU cache.
320 for (int i = 1; i < cache_size; ++i) {
321 res = _pc_descs[i];
322 if (res->pc_offset() < 0) break; // optimization: skip empty cache
323 if (match_desc(res, pc_offset, approximate)) {
324 NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
325 return res;
326 }
327 }
328
329 // Report failure.
330 return NULL;
331 }
332
333 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
334 NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
335 // Update the LRU cache by shifting pc_desc forward.
336 for (int i = 0; i < cache_size; i++) {
337 PcDesc* next = _pc_descs[i];
338 _pc_descs[i] = pc_desc;
339 pc_desc = next;
340 }
341 }
342
343 // adjust pcs_size so that it is a multiple of both oopSize and
344 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
345 // of oopSize, then 2*sizeof(PcDesc) is)
346 static int adjust_pcs_size(int pcs_size) {
347 int nsize = round_to(pcs_size, oopSize);
348 if ((nsize % sizeof(PcDesc)) != 0) {
349 nsize = pcs_size + sizeof(PcDesc);
350 }
351 assert((nsize % oopSize) == 0, "correct alignment");
352 return nsize;
353 }
354
355 //-----------------------------------------------------------------------------
356
357
358 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
359 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
360 assert(new_entry != NULL,"Must be non null");
361 assert(new_entry->next() == NULL, "Must be null");
362
363 if (exception_cache() != NULL) {
364 new_entry->set_next(exception_cache());
365 }
366 set_exception_cache(new_entry);
367 }
368
369 void nmethod::clean_exception_cache(BoolObjectClosure* is_alive) {
370 ExceptionCache* prev = NULL;
371 ExceptionCache* curr = exception_cache();
372
373 while (curr != NULL) {
374 ExceptionCache* next = curr->next();
375
376 Klass* ex_klass = curr->exception_type();
377 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
378 if (prev == NULL) {
379 set_exception_cache(next);
380 } else {
381 prev->set_next(next);
382 }
383 delete curr;
384 // prev stays the same.
385 } else {
386 prev = curr;
387 }
388
389 curr = next;
390 }
391 }
392
393 // public method for accessing the exception cache
394 // These are the public access methods.
395 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
396 // We never grab a lock to read the exception cache, so we may
397 // have false negatives. This is okay, as it can only happen during
398 // the first few exception lookups for a given nmethod.
399 ExceptionCache* ec = exception_cache();
400 while (ec != NULL) {
401 address ret_val;
402 if ((ret_val = ec->match(exception,pc)) != NULL) {
403 return ret_val;
404 }
405 ec = ec->next();
406 }
407 return NULL;
408 }
409
410
411 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
412 // There are potential race conditions during exception cache updates, so we
413 // must own the ExceptionCache_lock before doing ANY modifications. Because
414 // we don't lock during reads, it is possible to have several threads attempt
415 // to update the cache with the same data. We need to check for already inserted
416 // copies of the current data before adding it.
417
418 MutexLocker ml(ExceptionCache_lock);
419 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
420
421 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
422 target_entry = new ExceptionCache(exception,pc,handler);
423 add_exception_cache_entry(target_entry);
424 }
425 }
426
427
428 //-------------end of code for ExceptionCache--------------
429
430
431 int nmethod::total_size() const {
432 return
433 consts_size() +
434 insts_size() +
435 stub_size() +
436 scopes_data_size() +
437 scopes_pcs_size() +
438 handler_table_size() +
439 nul_chk_table_size();
440 }
441
442 const char* nmethod::compile_kind() const {
443 if (is_osr_method()) return "osr";
444 if (method() != NULL && is_native_method()) return "c2n";
445 return NULL;
446 }
447
448 // Fill in default values for various flag fields
449 void nmethod::init_defaults() {
450 _state = in_use;
451 _unloading_clock = 0;
452 _marked_for_reclamation = 0;
453 _has_flushed_dependencies = 0;
454 _has_unsafe_access = 0;
455 _has_method_handle_invokes = 0;
456 _lazy_critical_native = 0;
457 _has_wide_vectors = 0;
458 _marked_for_deoptimization = 0;
459 _lock_count = 0;
460 _stack_traversal_mark = 0;
461 _unload_reported = false; // jvmti state
462
463 #ifdef ASSERT
464 _oops_are_stale = false;
465 #endif
466
467 _oops_do_mark_link = NULL;
468 _jmethod_id = NULL;
469 _osr_link = NULL;
470 if (UseG1GC) {
471 _unloading_next = NULL;
472 } else {
473 _scavenge_root_link = NULL;
474 }
475 _scavenge_root_state = 0;
476 _compiler = NULL;
477 #if INCLUDE_RTM_OPT
478 _rtm_state = NoRTM;
479 #endif
480 #ifdef HAVE_DTRACE_H
481 _trap_offset = 0;
482 #endif // def HAVE_DTRACE_H
483 }
484
485 nmethod* nmethod::new_native_nmethod(methodHandle method,
486 int compile_id,
487 CodeBuffer *code_buffer,
488 int vep_offset,
489 int frame_complete,
490 int frame_size,
491 ByteSize basic_lock_owner_sp_offset,
492 ByteSize basic_lock_sp_offset,
493 OopMapSet* oop_maps) {
494 code_buffer->finalize_oop_references(method);
495 // create nmethod
496 nmethod* nm = NULL;
497 {
498 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
499 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
500 CodeOffsets offsets;
501 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
502 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
503 nm = new (native_nmethod_size) nmethod(method(), native_nmethod_size,
504 compile_id, &offsets,
505 code_buffer, frame_size,
506 basic_lock_owner_sp_offset,
507 basic_lock_sp_offset, oop_maps);
508 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm));
509 if (PrintAssembly && nm != NULL) {
510 Disassembler::decode(nm);
511 }
512 }
513 // verify nmethod
514 debug_only(if (nm) nm->verify();) // might block
515
516 if (nm != NULL) {
517 nm->log_new_nmethod();
518 }
519
520 return nm;
521 }
522
523 #ifdef HAVE_DTRACE_H
524 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
525 CodeBuffer *code_buffer,
526 int vep_offset,
527 int trap_offset,
528 int frame_complete,
529 int frame_size) {
530 code_buffer->finalize_oop_references(method);
531 // create nmethod
532 nmethod* nm = NULL;
533 {
534 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
535 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
536 CodeOffsets offsets;
537 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
538 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
539 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
540
541 nm = new (nmethod_size) nmethod(method(), nmethod_size,
542 &offsets, code_buffer, frame_size);
543
544 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
545 if (PrintAssembly && nm != NULL) {
546 Disassembler::decode(nm);
547 }
548 }
549 // verify nmethod
550 debug_only(if (nm) nm->verify();) // might block
551
552 if (nm != NULL) {
553 nm->log_new_nmethod();
554 }
555
556 return nm;
557 }
558
559 #endif // def HAVE_DTRACE_H
560
561 nmethod* nmethod::new_nmethod(methodHandle method,
562 int compile_id,
563 int entry_bci,
564 CodeOffsets* offsets,
565 int orig_pc_offset,
566 DebugInformationRecorder* debug_info,
567 Dependencies* dependencies,
568 CodeBuffer* code_buffer, int frame_size,
569 OopMapSet* oop_maps,
570 ExceptionHandlerTable* handler_table,
571 ImplicitExceptionTable* nul_chk_table,
572 AbstractCompiler* compiler,
573 int comp_level
574 )
575 {
576 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
577 code_buffer->finalize_oop_references(method);
578 // create nmethod
579 nmethod* nm = NULL;
580 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
581 int nmethod_size =
582 allocation_size(code_buffer, sizeof(nmethod))
583 + adjust_pcs_size(debug_info->pcs_size())
584 + round_to(dependencies->size_in_bytes() , oopSize)
585 + round_to(handler_table->size_in_bytes(), oopSize)
586 + round_to(nul_chk_table->size_in_bytes(), oopSize)
587 + round_to(debug_info->data_size() , oopSize);
588
589 nm = new (nmethod_size)
590 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
591 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
592 oop_maps,
593 handler_table,
594 nul_chk_table,
595 compiler,
596 comp_level);
597
598 if (nm != NULL) {
599 // To make dependency checking during class loading fast, record
600 // the nmethod dependencies in the classes it is dependent on.
601 // This allows the dependency checking code to simply walk the
602 // class hierarchy above the loaded class, checking only nmethods
603 // which are dependent on those classes. The slow way is to
604 // check every nmethod for dependencies which makes it linear in
605 // the number of methods compiled. For applications with a lot
606 // classes the slow way is too slow.
607 for (Dependencies::DepStream deps(nm); deps.next(); ) {
608 Klass* klass = deps.context_type();
609 if (klass == NULL) {
610 continue; // ignore things like evol_method
611 }
612
613 // record this nmethod as dependent on this klass
614 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
615 }
616 NOT_PRODUCT(nmethod_stats.note_nmethod(nm));
617 if (PrintAssembly || CompilerOracle::has_option_string(method, "PrintAssembly")) {
618 Disassembler::decode(nm);
619 }
620 }
621 }
622 // Do verification and logging outside CodeCache_lock.
623 if (nm != NULL) {
624 // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
625 DEBUG_ONLY(nm->verify();)
626 nm->log_new_nmethod();
627 }
628 return nm;
629 }
630
631
632 // For native wrappers
633 nmethod::nmethod(
634 Method* method,
635 int nmethod_size,
636 int compile_id,
637 CodeOffsets* offsets,
638 CodeBuffer* code_buffer,
639 int frame_size,
640 ByteSize basic_lock_owner_sp_offset,
641 ByteSize basic_lock_sp_offset,
642 OopMapSet* oop_maps )
643 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
644 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
645 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
646 _native_basic_lock_sp_offset(basic_lock_sp_offset)
647 {
648 {
649 debug_only(No_Safepoint_Verifier nsv;)
650 assert_locked_or_safepoint(CodeCache_lock);
651
652 init_defaults();
653 _method = method;
654 _entry_bci = InvocationEntryBci;
655 // We have no exception handler or deopt handler make the
656 // values something that will never match a pc like the nmethod vtable entry
657 _exception_offset = 0;
658 _deoptimize_offset = 0;
659 _deoptimize_mh_offset = 0;
660 _orig_pc_offset = 0;
661
662 _consts_offset = data_offset();
663 _stub_offset = data_offset();
664 _oops_offset = data_offset();
665 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
666 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
667 _scopes_pcs_offset = _scopes_data_offset;
668 _dependencies_offset = _scopes_pcs_offset;
669 _handler_table_offset = _dependencies_offset;
670 _nul_chk_table_offset = _handler_table_offset;
671 _nmethod_end_offset = _nul_chk_table_offset;
672 _compile_id = compile_id;
673 _comp_level = CompLevel_none;
674 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
675 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
676 _osr_entry_point = NULL;
677 _exception_cache = NULL;
678 _pc_desc_cache.reset_to(NULL);
679 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
680
681 code_buffer->copy_values_to(this);
682 if (ScavengeRootsInCode) {
683 if (detect_scavenge_root_oops()) {
684 CodeCache::add_scavenge_root_nmethod(this);
685 }
686 Universe::heap()->register_nmethod(this);
687 }
688 debug_only(verify_scavenge_root_oops());
689 CodeCache::commit(this);
690 }
691
692 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
693 ttyLocker ttyl; // keep the following output all in one block
694 // This output goes directly to the tty, not the compiler log.
695 // To enable tools to match it up with the compilation activity,
696 // be sure to tag this tty output with the compile ID.
697 if (xtty != NULL) {
698 xtty->begin_head("print_native_nmethod");
699 xtty->method(_method);
700 xtty->stamp();
701 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
702 }
703 // print the header part first
704 print();
705 // then print the requested information
706 if (PrintNativeNMethods) {
707 print_code();
708 if (oop_maps != NULL) {
709 oop_maps->print();
710 }
711 }
712 if (PrintRelocations) {
713 print_relocations();
714 }
715 if (xtty != NULL) {
716 xtty->tail("print_native_nmethod");
717 }
718 }
719 }
720
721 // For dtrace wrappers
722 #ifdef HAVE_DTRACE_H
723 nmethod::nmethod(
724 Method* method,
725 int nmethod_size,
726 CodeOffsets* offsets,
727 CodeBuffer* code_buffer,
728 int frame_size)
729 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
730 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
731 _native_receiver_sp_offset(in_ByteSize(-1)),
732 _native_basic_lock_sp_offset(in_ByteSize(-1))
733 {
734 {
735 debug_only(No_Safepoint_Verifier nsv;)
736 assert_locked_or_safepoint(CodeCache_lock);
737
738 init_defaults();
739 _method = method;
740 _entry_bci = InvocationEntryBci;
741 // We have no exception handler or deopt handler make the
742 // values something that will never match a pc like the nmethod vtable entry
743 _exception_offset = 0;
744 _deoptimize_offset = 0;
745 _deoptimize_mh_offset = 0;
746 _unwind_handler_offset = -1;
747 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
748 _orig_pc_offset = 0;
749 _consts_offset = data_offset();
750 _stub_offset = data_offset();
751 _oops_offset = data_offset();
752 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
753 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
754 _scopes_pcs_offset = _scopes_data_offset;
755 _dependencies_offset = _scopes_pcs_offset;
756 _handler_table_offset = _dependencies_offset;
757 _nul_chk_table_offset = _handler_table_offset;
758 _nmethod_end_offset = _nul_chk_table_offset;
759 _compile_id = 0; // default
760 _comp_level = CompLevel_none;
761 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
762 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
763 _osr_entry_point = NULL;
764 _exception_cache = NULL;
765 _pc_desc_cache.reset_to(NULL);
766 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
767
768 code_buffer->copy_values_to(this);
769 if (ScavengeRootsInCode) {
770 if (detect_scavenge_root_oops()) {
771 CodeCache::add_scavenge_root_nmethod(this);
772 }
773 Universe::heap()->register_nmethod(this);
774 }
775 DEBUG_ONLY(verify_scavenge_root_oops();)
776 CodeCache::commit(this);
777 }
778
779 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
780 ttyLocker ttyl; // keep the following output all in one block
781 // This output goes directly to the tty, not the compiler log.
782 // To enable tools to match it up with the compilation activity,
783 // be sure to tag this tty output with the compile ID.
784 if (xtty != NULL) {
785 xtty->begin_head("print_dtrace_nmethod");
786 xtty->method(_method);
787 xtty->stamp();
788 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
789 }
790 // print the header part first
791 print();
792 // then print the requested information
793 if (PrintNMethods) {
794 print_code();
795 }
796 if (PrintRelocations) {
797 print_relocations();
798 }
799 if (xtty != NULL) {
800 xtty->tail("print_dtrace_nmethod");
801 }
802 }
803 }
804 #endif // def HAVE_DTRACE_H
805
806 void* nmethod::operator new(size_t size, int nmethod_size) throw() {
807 // Not critical, may return null if there is too little continuous memory
808 return CodeCache::allocate(nmethod_size);
809 }
810
811 nmethod::nmethod(
812 Method* method,
813 int nmethod_size,
814 int compile_id,
815 int entry_bci,
816 CodeOffsets* offsets,
817 int orig_pc_offset,
818 DebugInformationRecorder* debug_info,
819 Dependencies* dependencies,
820 CodeBuffer *code_buffer,
821 int frame_size,
822 OopMapSet* oop_maps,
823 ExceptionHandlerTable* handler_table,
824 ImplicitExceptionTable* nul_chk_table,
825 AbstractCompiler* compiler,
826 int comp_level
827 )
828 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
829 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
830 _native_receiver_sp_offset(in_ByteSize(-1)),
831 _native_basic_lock_sp_offset(in_ByteSize(-1))
832 {
833 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
834 {
835 debug_only(No_Safepoint_Verifier nsv;)
836 assert_locked_or_safepoint(CodeCache_lock);
837
838 init_defaults();
839 _method = method;
840 _entry_bci = entry_bci;
841 _compile_id = compile_id;
842 _comp_level = comp_level;
843 _compiler = compiler;
844 _orig_pc_offset = orig_pc_offset;
845 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
846
847 // Section offsets
848 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
849 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
850
851 // Exception handler and deopt handler are in the stub section
852 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
853 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
854 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
855 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
856 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
857 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
858 } else {
859 _deoptimize_mh_offset = -1;
860 }
861 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
862 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
863 } else {
864 _unwind_handler_offset = -1;
865 }
866
867 _oops_offset = data_offset();
868 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
869 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
870
871 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
872 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
873 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
874 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
875 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
876
877 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
878 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
879 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
880 _exception_cache = NULL;
881 _pc_desc_cache.reset_to(scopes_pcs_begin());
882
883 // Copy contents of ScopeDescRecorder to nmethod
884 code_buffer->copy_values_to(this);
885 debug_info->copy_to(this);
886 dependencies->copy_to(this);
887 if (ScavengeRootsInCode) {
888 if (detect_scavenge_root_oops()) {
889 CodeCache::add_scavenge_root_nmethod(this);
890 }
891 Universe::heap()->register_nmethod(this);
892 }
893 debug_only(verify_scavenge_root_oops());
894
895 CodeCache::commit(this);
896
897 // Copy contents of ExceptionHandlerTable to nmethod
898 handler_table->copy_to(this);
899 nul_chk_table->copy_to(this);
900
901 // we use the information of entry points to find out if a method is
902 // static or non static
903 assert(compiler->is_c2() ||
904 _method->is_static() == (entry_point() == _verified_entry_point),
905 " entry points must be same for static methods and vice versa");
906 }
907
908 bool printnmethods = PrintNMethods
909 || CompilerOracle::should_print(_method)
910 || CompilerOracle::has_option_string(_method, "PrintNMethods");
911 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
912 print_nmethod(printnmethods);
913 }
914 }
915
916
917 // Print a short set of xml attributes to identify this nmethod. The
918 // output should be embedded in some other element.
919 void nmethod::log_identity(xmlStream* log) const {
920 log->print(" compile_id='%d'", compile_id());
921 const char* nm_kind = compile_kind();
922 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
923 if (compiler() != NULL) {
924 log->print(" compiler='%s'", compiler()->name());
925 }
926 if (TieredCompilation) {
927 log->print(" level='%d'", comp_level());
928 }
929 }
930
931
932 #define LOG_OFFSET(log, name) \
933 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
934 log->print(" " XSTR(name) "_offset='%d'" , \
935 (intptr_t)name##_begin() - (intptr_t)this)
936
937
938 void nmethod::log_new_nmethod() const {
939 if (LogCompilation && xtty != NULL) {
940 ttyLocker ttyl;
941 HandleMark hm;
942 xtty->begin_elem("nmethod");
943 log_identity(xtty);
944 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
945 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
946
947 LOG_OFFSET(xtty, relocation);
948 LOG_OFFSET(xtty, consts);
949 LOG_OFFSET(xtty, insts);
950 LOG_OFFSET(xtty, stub);
951 LOG_OFFSET(xtty, scopes_data);
952 LOG_OFFSET(xtty, scopes_pcs);
953 LOG_OFFSET(xtty, dependencies);
954 LOG_OFFSET(xtty, handler_table);
955 LOG_OFFSET(xtty, nul_chk_table);
956 LOG_OFFSET(xtty, oops);
957
958 xtty->method(method());
959 xtty->stamp();
960 xtty->end_elem();
961 }
962 }
963
964 #undef LOG_OFFSET
965
966
967 // Print out more verbose output usually for a newly created nmethod.
968 void nmethod::print_on(outputStream* st, const char* msg) const {
969 if (st != NULL) {
970 ttyLocker ttyl;
971 if (WizardMode) {
972 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
973 st->print_cr(" (" INTPTR_FORMAT ")", this);
974 } else {
975 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
976 }
977 }
978 }
979
980
981 void nmethod::print_nmethod(bool printmethod) {
982 ttyLocker ttyl; // keep the following output all in one block
983 if (xtty != NULL) {
984 xtty->begin_head("print_nmethod");
985 xtty->stamp();
986 xtty->end_head();
987 }
988 // print the header part first
989 print();
990 // then print the requested information
991 if (printmethod) {
992 print_code();
993 print_pcs();
994 if (oop_maps()) {
995 oop_maps()->print();
996 }
997 }
998 if (PrintDebugInfo) {
999 print_scopes();
1000 }
1001 if (PrintRelocations) {
1002 print_relocations();
1003 }
1004 if (PrintDependencies) {
1005 print_dependencies();
1006 }
1007 if (PrintExceptionHandlers) {
1008 print_handler_table();
1009 print_nul_chk_table();
1010 }
1011 if (xtty != NULL) {
1012 xtty->tail("print_nmethod");
1013 }
1014 }
1015
1016
1017 // Promote one word from an assembly-time handle to a live embedded oop.
1018 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1019 if (handle == NULL ||
1020 // As a special case, IC oops are initialized to 1 or -1.
1021 handle == (jobject) Universe::non_oop_word()) {
1022 (*dest) = (oop) handle;
1023 } else {
1024 (*dest) = JNIHandles::resolve_non_null(handle);
1025 }
1026 }
1027
1028
1029 // Have to have the same name because it's called by a template
1030 void nmethod::copy_values(GrowableArray<jobject>* array) {
1031 int length = array->length();
1032 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1033 oop* dest = oops_begin();
1034 for (int index = 0 ; index < length; index++) {
1035 initialize_immediate_oop(&dest[index], array->at(index));
1036 }
1037
1038 // Now we can fix up all the oops in the code. We need to do this
1039 // in the code because the assembler uses jobjects as placeholders.
1040 // The code and relocations have already been initialized by the
1041 // CodeBlob constructor, so it is valid even at this early point to
1042 // iterate over relocations and patch the code.
1043 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1044 }
1045
1046 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1047 int length = array->length();
1048 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1049 Metadata** dest = metadata_begin();
1050 for (int index = 0 ; index < length; index++) {
1051 dest[index] = array->at(index);
1052 }
1053 }
1054
1055 bool nmethod::is_at_poll_return(address pc) {
1056 RelocIterator iter(this, pc, pc+1);
1057 while (iter.next()) {
1058 if (iter.type() == relocInfo::poll_return_type)
1059 return true;
1060 }
1061 return false;
1062 }
1063
1064
1065 bool nmethod::is_at_poll_or_poll_return(address pc) {
1066 RelocIterator iter(this, pc, pc+1);
1067 while (iter.next()) {
1068 relocInfo::relocType t = iter.type();
1069 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1070 return true;
1071 }
1072 return false;
1073 }
1074
1075
1076 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1077 // re-patch all oop-bearing instructions, just in case some oops moved
1078 RelocIterator iter(this, begin, end);
1079 while (iter.next()) {
1080 if (iter.type() == relocInfo::oop_type) {
1081 oop_Relocation* reloc = iter.oop_reloc();
1082 if (initialize_immediates && reloc->oop_is_immediate()) {
1083 oop* dest = reloc->oop_addr();
1084 initialize_immediate_oop(dest, (jobject) *dest);
1085 }
1086 // Refresh the oop-related bits of this instruction.
1087 reloc->fix_oop_relocation();
1088 } else if (iter.type() == relocInfo::metadata_type) {
1089 metadata_Relocation* reloc = iter.metadata_reloc();
1090 reloc->fix_metadata_relocation();
1091 }
1092 }
1093 }
1094
1095
1096 void nmethod::verify_oop_relocations() {
1097 // Ensure sure that the code matches the current oop values
1098 RelocIterator iter(this, NULL, NULL);
1099 while (iter.next()) {
1100 if (iter.type() == relocInfo::oop_type) {
1101 oop_Relocation* reloc = iter.oop_reloc();
1102 if (!reloc->oop_is_immediate()) {
1103 reloc->verify_oop_relocation();
1104 }
1105 }
1106 }
1107 }
1108
1109
1110 ScopeDesc* nmethod::scope_desc_at(address pc) {
1111 PcDesc* pd = pc_desc_at(pc);
1112 guarantee(pd != NULL, "scope must be present");
1113 return new ScopeDesc(this, pd->scope_decode_offset(),
1114 pd->obj_decode_offset(), pd->should_reexecute(),
1115 pd->return_oop());
1116 }
1117
1118
1119 void nmethod::clear_inline_caches() {
1120 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1121 if (is_zombie()) {
1122 return;
1123 }
1124
1125 RelocIterator iter(this);
1126 while (iter.next()) {
1127 iter.reloc()->clear_inline_cache();
1128 }
1129 }
1130
1131
1132 void nmethod::cleanup_inline_caches() {
1133
1134 assert_locked_or_safepoint(CompiledIC_lock);
1135
1136 // If the method is not entrant or zombie then a JMP is plastered over the
1137 // first few bytes. If an oop in the old code was there, that oop
1138 // should not get GC'd. Skip the first few bytes of oops on
1139 // not-entrant methods.
1140 address low_boundary = verified_entry_point();
1141 if (!is_in_use()) {
1142 low_boundary += NativeJump::instruction_size;
1143 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1144 // This means that the low_boundary is going to be a little too high.
1145 // This shouldn't matter, since oops of non-entrant methods are never used.
1146 // In fact, why are we bothering to look at oops in a non-entrant method??
1147 }
1148
1149 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1150 ResourceMark rm;
1151 RelocIterator iter(this, low_boundary);
1152 while(iter.next()) {
1153 switch(iter.type()) {
1154 case relocInfo::virtual_call_type:
1155 case relocInfo::opt_virtual_call_type: {
1156 CompiledIC *ic = CompiledIC_at(&iter);
1157 // Ok, to lookup references to zombies here
1158 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1159 if( cb != NULL && cb->is_nmethod() ) {
1160 nmethod* nm = (nmethod*)cb;
1161 // Clean inline caches pointing to both zombie and not_entrant methods
1162 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1163 }
1164 break;
1165 }
1166 case relocInfo::static_call_type: {
1167 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1168 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1169 if( cb != NULL && cb->is_nmethod() ) {
1170 nmethod* nm = (nmethod*)cb;
1171 // Clean inline caches pointing to both zombie and not_entrant methods
1172 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1173 }
1174 break;
1175 }
1176 }
1177 }
1178 }
1179
1180 void nmethod::verify_clean_inline_caches() {
1181 assert_locked_or_safepoint(CompiledIC_lock);
1182
1183 // If the method is not entrant or zombie then a JMP is plastered over the
1184 // first few bytes. If an oop in the old code was there, that oop
1185 // should not get GC'd. Skip the first few bytes of oops on
1186 // not-entrant methods.
1187 address low_boundary = verified_entry_point();
1188 if (!is_in_use()) {
1189 low_boundary += NativeJump::instruction_size;
1190 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1191 // This means that the low_boundary is going to be a little too high.
1192 // This shouldn't matter, since oops of non-entrant methods are never used.
1193 // In fact, why are we bothering to look at oops in a non-entrant method??
1194 }
1195
1196 ResourceMark rm;
1197 RelocIterator iter(this, low_boundary);
1198 while(iter.next()) {
1199 switch(iter.type()) {
1200 case relocInfo::virtual_call_type:
1201 case relocInfo::opt_virtual_call_type: {
1202 CompiledIC *ic = CompiledIC_at(&iter);
1203 // Ok, to lookup references to zombies here
1204 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1205 if( cb != NULL && cb->is_nmethod() ) {
1206 nmethod* nm = (nmethod*)cb;
1207 // Verify that inline caches pointing to both zombie and not_entrant methods are clean
1208 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1209 assert(ic->is_clean(), "IC should be clean");
1210 }
1211 }
1212 break;
1213 }
1214 case relocInfo::static_call_type: {
1215 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1216 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1217 if( cb != NULL && cb->is_nmethod() ) {
1218 nmethod* nm = (nmethod*)cb;
1219 // Verify that inline caches pointing to both zombie and not_entrant methods are clean
1220 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1221 assert(csc->is_clean(), "IC should be clean");
1222 }
1223 }
1224 break;
1225 }
1226 }
1227 }
1228 }
1229
1230 int nmethod::verify_icholder_relocations() {
1231 int count = 0;
1232
1233 RelocIterator iter(this);
1234 while(iter.next()) {
1235 if (iter.type() == relocInfo::virtual_call_type) {
1236 if (CompiledIC::is_icholder_call_site(iter.virtual_call_reloc())) {
1237 CompiledIC *ic = CompiledIC_at(&iter);
1238 if (TraceCompiledIC) {
1239 tty->print("noticed icholder " INTPTR_FORMAT " ", p2i(ic->cached_icholder()));
1240 ic->print();
1241 }
1242 assert(ic->cached_icholder() != NULL, "must be non-NULL");
1243 count++;
1244 }
1245 }
1246 }
1247
1248 return count;
1249 }
1250
1251 // This is a private interface with the sweeper.
1252 void nmethod::mark_as_seen_on_stack() {
1253 assert(is_alive(), "Must be an alive method");
1254 // Set the traversal mark to ensure that the sweeper does 2
1255 // cleaning passes before moving to zombie.
1256 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1257 }
1258
1259 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1260 // there are no activations on the stack, not in use by the VM,
1261 // and not in use by the ServiceThread)
1262 bool nmethod::can_not_entrant_be_converted() {
1263 assert(is_not_entrant(), "must be a non-entrant method");
1264
1265 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1266 // count can be greater than the stack traversal count before it hits the
1267 // nmethod for the second time.
1268 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1269 !is_locked_by_vm();
1270 }
1271
1272 void nmethod::inc_decompile_count() {
1273 if (!is_compiled_by_c2()) return;
1274 // Could be gated by ProfileTraps, but do not bother...
1275 Method* m = method();
1276 if (m == NULL) return;
1277 MethodData* mdo = m->method_data();
1278 if (mdo == NULL) return;
1279 // There is a benign race here. See comments in methodData.hpp.
1280 mdo->inc_decompile_count();
1281 }
1282
1283 void nmethod::increase_unloading_clock() {
1284 _global_unloading_clock++;
1285 if (_global_unloading_clock == 0) {
1286 // _nmethods are allocated with _unloading_clock == 0,
1287 // so 0 is never used as a clock value.
1288 _global_unloading_clock = 1;
1289 }
1290 }
1291
1292 void nmethod::set_unloading_clock(unsigned char unloading_clock) {
1293 OrderAccess::release_store((volatile jubyte*)&_unloading_clock, unloading_clock);
1294 }
1295
1296 unsigned char nmethod::unloading_clock() {
1297 return (unsigned char)OrderAccess::load_acquire((volatile jubyte*)&_unloading_clock);
1298 }
1299
1300 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1301
1302 post_compiled_method_unload();
1303
1304 // Since this nmethod is being unloaded, make sure that dependencies
1305 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1306 // indicate that this work is being done during a GC.
1307 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1308 assert(is_alive != NULL, "Should be non-NULL");
1309 // A non-NULL is_alive closure indicates that this is being called during GC.
1310 flush_dependencies(is_alive);
1311
1312 // Break cycle between nmethod & method
1313 if (TraceClassUnloading && WizardMode) {
1314 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1315 " unloadable], Method*(" INTPTR_FORMAT
1316 "), cause(" INTPTR_FORMAT ")",
1317 this, (address)_method, (address)cause);
1318 if (!Universe::heap()->is_gc_active())
1319 cause->klass()->print();
1320 }
1321 // Unlink the osr method, so we do not look this up again
1322 if (is_osr_method()) {
1323 invalidate_osr_method();
1324 }
1325 // If _method is already NULL the Method* is about to be unloaded,
1326 // so we don't have to break the cycle. Note that it is possible to
1327 // have the Method* live here, in case we unload the nmethod because
1328 // it is pointing to some oop (other than the Method*) being unloaded.
1329 if (_method != NULL) {
1330 // OSR methods point to the Method*, but the Method* does not
1331 // point back!
1332 if (_method->code() == this) {
1333 _method->clear_code(); // Break a cycle
1334 }
1335 _method = NULL; // Clear the method of this dead nmethod
1336 }
1337 // Make the class unloaded - i.e., change state and notify sweeper
1338 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1339 if (is_in_use()) {
1340 // Transitioning directly from live to unloaded -- so
1341 // we need to force a cache clean-up; remember this
1342 // for later on.
1343 CodeCache::set_needs_cache_clean(true);
1344 }
1345
1346 // Unregister must be done before the state change
1347 Universe::heap()->unregister_nmethod(this);
1348
1349 _state = unloaded;
1350
1351 // Log the unloading.
1352 log_state_change();
1353
1354 // The Method* is gone at this point
1355 assert(_method == NULL, "Tautology");
1356
1357 set_osr_link(NULL);
1358 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1359 NMethodSweeper::report_state_change(this);
1360 }
1361
1362 void nmethod::invalidate_osr_method() {
1363 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1364 // Remove from list of active nmethods
1365 if (method() != NULL)
1366 method()->method_holder()->remove_osr_nmethod(this);
1367 // Set entry as invalid
1368 _entry_bci = InvalidOSREntryBci;
1369 }
1370
1371 void nmethod::log_state_change() const {
1372 if (LogCompilation) {
1373 if (xtty != NULL) {
1374 ttyLocker ttyl; // keep the following output all in one block
1375 if (_state == unloaded) {
1376 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1377 os::current_thread_id());
1378 } else {
1379 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1380 os::current_thread_id(),
1381 (_state == zombie ? " zombie='1'" : ""));
1382 }
1383 log_identity(xtty);
1384 xtty->stamp();
1385 xtty->end_elem();
1386 }
1387 }
1388 if (PrintCompilation && _state != unloaded) {
1389 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1390 }
1391 }
1392
1393 /**
1394 * Common functionality for both make_not_entrant and make_zombie
1395 */
1396 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1397 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1398 assert(!is_zombie(), "should not already be a zombie");
1399
1400 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1401 nmethodLocker nml(this);
1402 methodHandle the_method(method());
1403 No_Safepoint_Verifier nsv;
1404
1405 // during patching, depending on the nmethod state we must notify the GC that
1406 // code has been unloaded, unregistering it. We cannot do this right while
1407 // holding the Patching_lock because we need to use the CodeCache_lock. This
1408 // would be prone to deadlocks.
1409 // This flag is used to remember whether we need to later lock and unregister.
1410 bool nmethod_needs_unregister = false;
1411
1412 {
1413 // invalidate osr nmethod before acquiring the patching lock since
1414 // they both acquire leaf locks and we don't want a deadlock.
1415 // This logic is equivalent to the logic below for patching the
1416 // verified entry point of regular methods.
1417 if (is_osr_method()) {
1418 // this effectively makes the osr nmethod not entrant
1419 invalidate_osr_method();
1420 }
1421
1422 // Enter critical section. Does not block for safepoint.
1423 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1424
1425 if (_state == state) {
1426 // another thread already performed this transition so nothing
1427 // to do, but return false to indicate this.
1428 return false;
1429 }
1430
1431 // The caller can be calling the method statically or through an inline
1432 // cache call.
1433 if (!is_osr_method() && !is_not_entrant()) {
1434 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1435 SharedRuntime::get_handle_wrong_method_stub());
1436 }
1437
1438 if (is_in_use()) {
1439 // It's a true state change, so mark the method as decompiled.
1440 // Do it only for transition from alive.
1441 inc_decompile_count();
1442 }
1443
1444 // If the state is becoming a zombie, signal to unregister the nmethod with
1445 // the heap.
1446 // This nmethod may have already been unloaded during a full GC.
1447 if ((state == zombie) && !is_unloaded()) {
1448 nmethod_needs_unregister = true;
1449 }
1450
1451 // Must happen before state change. Otherwise we have a race condition in
1452 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1453 // transition its state from 'not_entrant' to 'zombie' without having to wait
1454 // for stack scanning.
1455 if (state == not_entrant) {
1456 mark_as_seen_on_stack();
1457 OrderAccess::storestore();
1458 }
1459
1460 // Change state
1461 _state = state;
1462
1463 // Log the transition once
1464 log_state_change();
1465
1466 // Remove nmethod from method.
1467 // We need to check if both the _code and _from_compiled_code_entry_point
1468 // refer to this nmethod because there is a race in setting these two fields
1469 // in Method* as seen in bugid 4947125.
1470 // If the vep() points to the zombie nmethod, the memory for the nmethod
1471 // could be flushed and the compiler and vtable stubs could still call
1472 // through it.
1473 if (method() != NULL && (method()->code() == this ||
1474 method()->from_compiled_entry() == verified_entry_point())) {
1475 HandleMark hm;
1476 method()->clear_code();
1477 }
1478 } // leave critical region under Patching_lock
1479
1480 // When the nmethod becomes zombie it is no longer alive so the
1481 // dependencies must be flushed. nmethods in the not_entrant
1482 // state will be flushed later when the transition to zombie
1483 // happens or they get unloaded.
1484 if (state == zombie) {
1485 {
1486 // Flushing dependecies must be done before any possible
1487 // safepoint can sneak in, otherwise the oops used by the
1488 // dependency logic could have become stale.
1489 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1490 if (nmethod_needs_unregister) {
1491 Universe::heap()->unregister_nmethod(this);
1492 }
1493 flush_dependencies(NULL);
1494 }
1495
1496 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1497 // event and it hasn't already been reported for this nmethod then
1498 // report it now. The event may have been reported earilier if the GC
1499 // marked it for unloading). JvmtiDeferredEventQueue support means
1500 // we no longer go to a safepoint here.
1501 post_compiled_method_unload();
1502
1503 #ifdef ASSERT
1504 // It's no longer safe to access the oops section since zombie
1505 // nmethods aren't scanned for GC.
1506 _oops_are_stale = true;
1507 #endif
1508 // the Method may be reclaimed by class unloading now that the
1509 // nmethod is in zombie state
1510 set_method(NULL);
1511 } else {
1512 assert(state == not_entrant, "other cases may need to be handled differently");
1513 }
1514
1515 if (TraceCreateZombies) {
1516 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1517 }
1518
1519 NMethodSweeper::report_state_change(this);
1520 return true;
1521 }
1522
1523 void nmethod::flush() {
1524 // Note that there are no valid oops in the nmethod anymore.
1525 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1526 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1527
1528 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1529 assert_locked_or_safepoint(CodeCache_lock);
1530
1531 // completely deallocate this method
1532 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1533 if (PrintMethodFlushing) {
1534 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1535 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
1536 }
1537
1538 // We need to deallocate any ExceptionCache data.
1539 // Note that we do not need to grab the nmethod lock for this, it
1540 // better be thread safe if we're disposing of it!
1541 ExceptionCache* ec = exception_cache();
1542 set_exception_cache(NULL);
1543 while(ec != NULL) {
1544 ExceptionCache* next = ec->next();
1545 delete ec;
1546 ec = next;
1547 }
1548
1549 if (on_scavenge_root_list()) {
1550 CodeCache::drop_scavenge_root_nmethod(this);
1551 }
1552
1553 #ifdef SHARK
1554 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1555 #endif // SHARK
1556
1557 ((CodeBlob*)(this))->flush();
1558
1559 CodeCache::free(this);
1560 }
1561
1562
1563 //
1564 // Notify all classes this nmethod is dependent on that it is no
1565 // longer dependent. This should only be called in two situations.
1566 // First, when a nmethod transitions to a zombie all dependents need
1567 // to be clear. Since zombification happens at a safepoint there's no
1568 // synchronization issues. The second place is a little more tricky.
1569 // During phase 1 of mark sweep class unloading may happen and as a
1570 // result some nmethods may get unloaded. In this case the flushing
1571 // of dependencies must happen during phase 1 since after GC any
1572 // dependencies in the unloaded nmethod won't be updated, so
1573 // traversing the dependency information in unsafe. In that case this
1574 // function is called with a non-NULL argument and this function only
1575 // notifies instanceKlasses that are reachable
1576
1577 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1578 assert_locked_or_safepoint(CodeCache_lock);
1579 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1580 "is_alive is non-NULL if and only if we are called during GC");
1581 if (!has_flushed_dependencies()) {
1582 set_has_flushed_dependencies();
1583 for (Dependencies::DepStream deps(this); deps.next(); ) {
1584 Klass* klass = deps.context_type();
1585 if (klass == NULL) continue; // ignore things like evol_method
1586
1587 // During GC the is_alive closure is non-NULL, and is used to
1588 // determine liveness of dependees that need to be updated.
1589 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1590 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1591 }
1592 }
1593 }
1594 }
1595
1596
1597 // If this oop is not live, the nmethod can be unloaded.
1598 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1599 assert(root != NULL, "just checking");
1600 oop obj = *root;
1601 if (obj == NULL || is_alive->do_object_b(obj)) {
1602 return false;
1603 }
1604
1605 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1606 // simply because one of its constant oops has gone dead.
1607 // No actual classes need to be unloaded in order for this to occur.
1608 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1609 make_unloaded(is_alive, obj);
1610 return true;
1611 }
1612
1613 // ------------------------------------------------------------------
1614 // post_compiled_method_load_event
1615 // new method for install_code() path
1616 // Transfer information from compilation to jvmti
1617 void nmethod::post_compiled_method_load_event() {
1618
1619 Method* moop = method();
1620 HOTSPOT_COMPILED_METHOD_LOAD(
1621 (char *) moop->klass_name()->bytes(),
1622 moop->klass_name()->utf8_length(),
1623 (char *) moop->name()->bytes(),
1624 moop->name()->utf8_length(),
1625 (char *) moop->signature()->bytes(),
1626 moop->signature()->utf8_length(),
1627 insts_begin(), insts_size());
1628
1629 if (JvmtiExport::should_post_compiled_method_load() ||
1630 JvmtiExport::should_post_compiled_method_unload()) {
1631 get_and_cache_jmethod_id();
1632 }
1633
1634 if (JvmtiExport::should_post_compiled_method_load()) {
1635 // Let the Service thread (which is a real Java thread) post the event
1636 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1637 JvmtiDeferredEventQueue::enqueue(
1638 JvmtiDeferredEvent::compiled_method_load_event(this));
1639 }
1640 }
1641
1642 jmethodID nmethod::get_and_cache_jmethod_id() {
1643 if (_jmethod_id == NULL) {
1644 // Cache the jmethod_id since it can no longer be looked up once the
1645 // method itself has been marked for unloading.
1646 _jmethod_id = method()->jmethod_id();
1647 }
1648 return _jmethod_id;
1649 }
1650
1651 void nmethod::post_compiled_method_unload() {
1652 if (unload_reported()) {
1653 // During unloading we transition to unloaded and then to zombie
1654 // and the unloading is reported during the first transition.
1655 return;
1656 }
1657
1658 assert(_method != NULL && !is_unloaded(), "just checking");
1659 DTRACE_METHOD_UNLOAD_PROBE(method());
1660
1661 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1662 // post the event. Sometime later this nmethod will be made a zombie
1663 // by the sweeper but the Method* will not be valid at that point.
1664 // If the _jmethod_id is null then no load event was ever requested
1665 // so don't bother posting the unload. The main reason for this is
1666 // that the jmethodID is a weak reference to the Method* so if
1667 // it's being unloaded there's no way to look it up since the weak
1668 // ref will have been cleared.
1669 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1670 assert(!unload_reported(), "already unloaded");
1671 JvmtiDeferredEvent event =
1672 JvmtiDeferredEvent::compiled_method_unload_event(this,
1673 _jmethod_id, insts_begin());
1674 if (SafepointSynchronize::is_at_safepoint()) {
1675 // Don't want to take the queueing lock. Add it as pending and
1676 // it will get enqueued later.
1677 JvmtiDeferredEventQueue::add_pending_event(event);
1678 } else {
1679 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1680 JvmtiDeferredEventQueue::enqueue(event);
1681 }
1682 }
1683
1684 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1685 // any time. As the nmethod is being unloaded now we mark it has
1686 // having the unload event reported - this will ensure that we don't
1687 // attempt to report the event in the unlikely scenario where the
1688 // event is enabled at the time the nmethod is made a zombie.
1689 set_unload_reported();
1690 }
1691
1692 void static clean_ic_if_metadata_is_dead(CompiledIC *ic, BoolObjectClosure *is_alive) {
1693 if (ic->is_icholder_call()) {
1694 // The only exception is compiledICHolder oops which may
1695 // yet be marked below. (We check this further below).
1696 CompiledICHolder* cichk_oop = ic->cached_icholder();
1697 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1698 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1699 return;
1700 }
1701 } else {
1702 Metadata* ic_oop = ic->cached_metadata();
1703 if (ic_oop != NULL) {
1704 if (ic_oop->is_klass()) {
1705 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1706 return;
1707 }
1708 } else if (ic_oop->is_method()) {
1709 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1710 return;
1711 }
1712 } else {
1713 ShouldNotReachHere();
1714 }
1715 }
1716 }
1717
1718 ic->set_to_clean();
1719 }
1720
1721 // This is called at the end of the strong tracing/marking phase of a
1722 // GC to unload an nmethod if it contains otherwise unreachable
1723 // oops.
1724
1725 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1726 // Make sure the oop's ready to receive visitors
1727 assert(!is_zombie() && !is_unloaded(),
1728 "should not call follow on zombie or unloaded nmethod");
1729
1730 // If the method is not entrant then a JMP is plastered over the
1731 // first few bytes. If an oop in the old code was there, that oop
1732 // should not get GC'd. Skip the first few bytes of oops on
1733 // not-entrant methods.
1734 address low_boundary = verified_entry_point();
1735 if (is_not_entrant()) {
1736 low_boundary += NativeJump::instruction_size;
1737 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1738 // (See comment above.)
1739 }
1740
1741 // The RedefineClasses() API can cause the class unloading invariant
1742 // to no longer be true. See jvmtiExport.hpp for details.
1743 // Also, leave a debugging breadcrumb in local flag.
1744 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1745 if (a_class_was_redefined) {
1746 // This set of the unloading_occurred flag is done before the
1747 // call to post_compiled_method_unload() so that the unloading
1748 // of this nmethod is reported.
1749 unloading_occurred = true;
1750 }
1751
1752 // Exception cache
1753 clean_exception_cache(is_alive);
1754
1755 // If class unloading occurred we first iterate over all inline caches and
1756 // clear ICs where the cached oop is referring to an unloaded klass or method.
1757 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1758 // iteration below.
1759 if (unloading_occurred) {
1760 RelocIterator iter(this, low_boundary);
1761 while(iter.next()) {
1762 if (iter.type() == relocInfo::virtual_call_type) {
1763 CompiledIC *ic = CompiledIC_at(&iter);
1764 clean_ic_if_metadata_is_dead(ic, is_alive);
1765 }
1766 }
1767 }
1768
1769 // Compiled code
1770 {
1771 RelocIterator iter(this, low_boundary);
1772 while (iter.next()) {
1773 if (iter.type() == relocInfo::oop_type) {
1774 oop_Relocation* r = iter.oop_reloc();
1775 // In this loop, we must only traverse those oops directly embedded in
1776 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1777 assert(1 == (r->oop_is_immediate()) +
1778 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1779 "oop must be found in exactly one place");
1780 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1781 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1782 return;
1783 }
1784 }
1785 }
1786 }
1787 }
1788
1789
1790 // Scopes
1791 for (oop* p = oops_begin(); p < oops_end(); p++) {
1792 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1793 if (can_unload(is_alive, p, unloading_occurred)) {
1794 return;
1795 }
1796 }
1797
1798 // Ensure that all metadata is still alive
1799 verify_metadata_loaders(low_boundary, is_alive);
1800 }
1801
1802 template <class CompiledICorStaticCall>
1803 static bool clean_if_nmethod_is_unloaded(CompiledICorStaticCall *ic, address addr, BoolObjectClosure *is_alive, nmethod* from) {
1804 // Ok, to lookup references to zombies here
1805 CodeBlob *cb = CodeCache::find_blob_unsafe(addr);
1806 if (cb != NULL && cb->is_nmethod()) {
1807 nmethod* nm = (nmethod*)cb;
1808
1809 if (nm->unloading_clock() != nmethod::global_unloading_clock()) {
1810 // The nmethod has not been processed yet.
1811 return true;
1812 }
1813
1814 // Clean inline caches pointing to both zombie and not_entrant methods
1815 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1816 ic->set_to_clean();
1817 assert(ic->is_clean(), err_msg("nmethod " PTR_FORMAT "not clean %s", from, from->method()->name_and_sig_as_C_string()));
1818 }
1819 }
1820
1821 return false;
1822 }
1823
1824 static bool clean_if_nmethod_is_unloaded(CompiledIC *ic, BoolObjectClosure *is_alive, nmethod* from) {
1825 return clean_if_nmethod_is_unloaded(ic, ic->ic_destination(), is_alive, from);
1826 }
1827
1828 static bool clean_if_nmethod_is_unloaded(CompiledStaticCall *csc, BoolObjectClosure *is_alive, nmethod* from) {
1829 return clean_if_nmethod_is_unloaded(csc, csc->destination(), is_alive, from);
1830 }
1831
1832 bool nmethod::do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred) {
1833 ResourceMark rm;
1834
1835 // Make sure the oop's ready to receive visitors
1836 assert(!is_zombie() && !is_unloaded(),
1837 "should not call follow on zombie or unloaded nmethod");
1838
1839 // If the method is not entrant then a JMP is plastered over the
1840 // first few bytes. If an oop in the old code was there, that oop
1841 // should not get GC'd. Skip the first few bytes of oops on
1842 // not-entrant methods.
1843 address low_boundary = verified_entry_point();
1844 if (is_not_entrant()) {
1845 low_boundary += NativeJump::instruction_size;
1846 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1847 // (See comment above.)
1848 }
1849
1850 // The RedefineClasses() API can cause the class unloading invariant
1851 // to no longer be true. See jvmtiExport.hpp for details.
1852 // Also, leave a debugging breadcrumb in local flag.
1853 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1854 if (a_class_was_redefined) {
1855 // This set of the unloading_occurred flag is done before the
1856 // call to post_compiled_method_unload() so that the unloading
1857 // of this nmethod is reported.
1858 unloading_occurred = true;
1859 }
1860
1861 // Exception cache
1862 clean_exception_cache(is_alive);
1863
1864 bool is_unloaded = false;
1865 bool postponed = false;
1866
1867 RelocIterator iter(this, low_boundary);
1868 while(iter.next()) {
1869
1870 switch (iter.type()) {
1871
1872 case relocInfo::virtual_call_type:
1873 if (unloading_occurred) {
1874 // If class unloading occurred we first iterate over all inline caches and
1875 // clear ICs where the cached oop is referring to an unloaded klass or method.
1876 clean_ic_if_metadata_is_dead(CompiledIC_at(&iter), is_alive);
1877 }
1878
1879 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1880 break;
1881
1882 case relocInfo::opt_virtual_call_type:
1883 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1884 break;
1885
1886 case relocInfo::static_call_type:
1887 postponed |= clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
1888 break;
1889
1890 case relocInfo::oop_type:
1891 if (!is_unloaded) {
1892 // Unload check
1893 oop_Relocation* r = iter.oop_reloc();
1894 // Traverse those oops directly embedded in the code.
1895 // Other oops (oop_index>0) are seen as part of scopes_oops.
1896 assert(1 == (r->oop_is_immediate()) +
1897 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1898 "oop must be found in exactly one place");
1899 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1900 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1901 is_unloaded = true;
1902 }
1903 }
1904 }
1905 break;
1906
1907 }
1908 }
1909
1910 if (is_unloaded) {
1911 return postponed;
1912 }
1913
1914 // Scopes
1915 for (oop* p = oops_begin(); p < oops_end(); p++) {
1916 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1917 if (can_unload(is_alive, p, unloading_occurred)) {
1918 is_unloaded = true;
1919 break;
1920 }
1921 }
1922
1923 if (is_unloaded) {
1924 return postponed;
1925 }
1926
1927 // Ensure that all metadata is still alive
1928 verify_metadata_loaders(low_boundary, is_alive);
1929
1930 return postponed;
1931 }
1932
1933 void nmethod::do_unloading_parallel_postponed(BoolObjectClosure* is_alive, bool unloading_occurred) {
1934 ResourceMark rm;
1935
1936 // Make sure the oop's ready to receive visitors
1937 assert(!is_zombie(),
1938 "should not call follow on zombie nmethod");
1939
1940 // If the method is not entrant then a JMP is plastered over the
1941 // first few bytes. If an oop in the old code was there, that oop
1942 // should not get GC'd. Skip the first few bytes of oops on
1943 // not-entrant methods.
1944 address low_boundary = verified_entry_point();
1945 if (is_not_entrant()) {
1946 low_boundary += NativeJump::instruction_size;
1947 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1948 // (See comment above.)
1949 }
1950
1951 RelocIterator iter(this, low_boundary);
1952 while(iter.next()) {
1953
1954 switch (iter.type()) {
1955
1956 case relocInfo::virtual_call_type:
1957 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1958 break;
1959
1960 case relocInfo::opt_virtual_call_type:
1961 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1962 break;
1963
1964 case relocInfo::static_call_type:
1965 clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
1966 break;
1967 }
1968 }
1969 }
1970
1971 #ifdef ASSERT
1972
1973 class CheckClass : AllStatic {
1974 static BoolObjectClosure* _is_alive;
1975
1976 // Check class_loader is alive for this bit of metadata.
1977 static void check_class(Metadata* md) {
1978 Klass* klass = NULL;
1979 if (md->is_klass()) {
1980 klass = ((Klass*)md);
1981 } else if (md->is_method()) {
1982 klass = ((Method*)md)->method_holder();
1983 } else if (md->is_methodData()) {
1984 klass = ((MethodData*)md)->method()->method_holder();
1985 } else {
1986 md->print();
1987 ShouldNotReachHere();
1988 }
1989 assert(klass->is_loader_alive(_is_alive), "must be alive");
1990 }
1991 public:
1992 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
1993 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
1994 _is_alive = is_alive;
1995 nm->metadata_do(check_class);
1996 }
1997 };
1998
1999 // This is called during a safepoint so can use static data
2000 BoolObjectClosure* CheckClass::_is_alive = NULL;
2001 #endif // ASSERT
2002
2003
2004 // Processing of oop references should have been sufficient to keep
2005 // all strong references alive. Any weak references should have been
2006 // cleared as well. Visit all the metadata and ensure that it's
2007 // really alive.
2008 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
2009 #ifdef ASSERT
2010 RelocIterator iter(this, low_boundary);
2011 while (iter.next()) {
2012 // static_stub_Relocations may have dangling references to
2013 // Method*s so trim them out here. Otherwise it looks like
2014 // compiled code is maintaining a link to dead metadata.
2015 address static_call_addr = NULL;
2016 if (iter.type() == relocInfo::opt_virtual_call_type) {
2017 CompiledIC* cic = CompiledIC_at(&iter);
2018 if (!cic->is_call_to_interpreted()) {
2019 static_call_addr = iter.addr();
2020 }
2021 } else if (iter.type() == relocInfo::static_call_type) {
2022 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
2023 if (!csc->is_call_to_interpreted()) {
2024 static_call_addr = iter.addr();
2025 }
2026 }
2027 if (static_call_addr != NULL) {
2028 RelocIterator sciter(this, low_boundary);
2029 while (sciter.next()) {
2030 if (sciter.type() == relocInfo::static_stub_type &&
2031 sciter.static_stub_reloc()->static_call() == static_call_addr) {
2032 sciter.static_stub_reloc()->clear_inline_cache();
2033 }
2034 }
2035 }
2036 }
2037 // Check that the metadata embedded in the nmethod is alive
2038 CheckClass::do_check_class(is_alive, this);
2039 #endif
2040 }
2041
2042
2043 // Iterate over metadata calling this function. Used by RedefineClasses
2044 void nmethod::metadata_do(void f(Metadata*)) {
2045 address low_boundary = verified_entry_point();
2046 if (is_not_entrant()) {
2047 low_boundary += NativeJump::instruction_size;
2048 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
2049 // (See comment above.)
2050 }
2051 {
2052 // Visit all immediate references that are embedded in the instruction stream.
2053 RelocIterator iter(this, low_boundary);
2054 while (iter.next()) {
2055 if (iter.type() == relocInfo::metadata_type ) {
2056 metadata_Relocation* r = iter.metadata_reloc();
2057 // In this lmetadata, we must only follow those metadatas directly embedded in
2058 // the code. Other metadatas (oop_index>0) are seen as part of
2059 // the metadata section below.
2060 assert(1 == (r->metadata_is_immediate()) +
2061 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
2062 "metadata must be found in exactly one place");
2063 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
2064 Metadata* md = r->metadata_value();
2065 f(md);
2066 }
2067 } else if (iter.type() == relocInfo::virtual_call_type) {
2068 // Check compiledIC holders associated with this nmethod
2069 CompiledIC *ic = CompiledIC_at(&iter);
2070 if (ic->is_icholder_call()) {
2071 CompiledICHolder* cichk = ic->cached_icholder();
2072 f(cichk->holder_method());
2073 f(cichk->holder_klass());
2074 } else {
2075 Metadata* ic_oop = ic->cached_metadata();
2076 if (ic_oop != NULL) {
2077 f(ic_oop);
2078 }
2079 }
2080 }
2081 }
2082 }
2083
2084 // Visit the metadata section
2085 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
2086 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
2087 Metadata* md = *p;
2088 f(md);
2089 }
2090
2091 // Call function Method*, not embedded in these other places.
2092 if (_method != NULL) f(_method);
2093 }
2094
2095 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
2096 // make sure the oops ready to receive visitors
2097 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
2098 assert(!is_unloaded(), "should not call follow on unloaded nmethod");
2099
2100 // If the method is not entrant or zombie then a JMP is plastered over the
2101 // first few bytes. If an oop in the old code was there, that oop
2102 // should not get GC'd. Skip the first few bytes of oops on
2103 // not-entrant methods.
2104 address low_boundary = verified_entry_point();
2105 if (is_not_entrant()) {
2106 low_boundary += NativeJump::instruction_size;
2107 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
2108 // (See comment above.)
2109 }
2110
2111 RelocIterator iter(this, low_boundary);
2112
2113 while (iter.next()) {
2114 if (iter.type() == relocInfo::oop_type ) {
2115 oop_Relocation* r = iter.oop_reloc();
2116 // In this loop, we must only follow those oops directly embedded in
2117 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
2118 assert(1 == (r->oop_is_immediate()) +
2119 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
2120 "oop must be found in exactly one place");
2121 if (r->oop_is_immediate() && r->oop_value() != NULL) {
2122 f->do_oop(r->oop_addr());
2123 }
2124 }
2125 }
2126
2127 // Scopes
2128 // This includes oop constants not inlined in the code stream.
2129 for (oop* p = oops_begin(); p < oops_end(); p++) {
2130 if (*p == Universe::non_oop_word()) continue; // skip non-oops
2131 f->do_oop(p);
2132 }
2133 }
2134
2135 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
2136
2137 nmethod* volatile nmethod::_oops_do_mark_nmethods;
2138
2139 // An nmethod is "marked" if its _mark_link is set non-null.
2140 // Even if it is the end of the linked list, it will have a non-null link value,
2141 // as long as it is on the list.
2142 // This code must be MP safe, because it is used from parallel GC passes.
2143 bool nmethod::test_set_oops_do_mark() {
2144 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
2145 nmethod* observed_mark_link = _oops_do_mark_link;
2146 if (observed_mark_link == NULL) {
2147 // Claim this nmethod for this thread to mark.
2148 observed_mark_link = (nmethod*)
2149 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
2150 if (observed_mark_link == NULL) {
2151
2152 // Atomically append this nmethod (now claimed) to the head of the list:
2153 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
2154 for (;;) {
2155 nmethod* required_mark_nmethods = observed_mark_nmethods;
2156 _oops_do_mark_link = required_mark_nmethods;
2157 observed_mark_nmethods = (nmethod*)
2158 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
2159 if (observed_mark_nmethods == required_mark_nmethods)
2160 break;
2161 }
2162 // Mark was clear when we first saw this guy.
2163 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
2164 return false;
2165 }
2166 }
2167 // On fall through, another racing thread marked this nmethod before we did.
2168 return true;
2169 }
2170
2171 void nmethod::oops_do_marking_prologue() {
2172 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
2173 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
2174 // We use cmpxchg_ptr instead of regular assignment here because the user
2175 // may fork a bunch of threads, and we need them all to see the same state.
2176 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
2177 guarantee(observed == NULL, "no races in this sequential code");
2178 }
2179
2180 void nmethod::oops_do_marking_epilogue() {
2181 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
2182 nmethod* cur = _oops_do_mark_nmethods;
2183 while (cur != NMETHOD_SENTINEL) {
2184 assert(cur != NULL, "not NULL-terminated");
2185 nmethod* next = cur->_oops_do_mark_link;
2186 cur->_oops_do_mark_link = NULL;
2187 cur->verify_oop_relocations();
2188 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
2189 cur = next;
2190 }
2191 void* required = _oops_do_mark_nmethods;
2192 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
2193 guarantee(observed == required, "no races in this sequential code");
2194 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
2195 }
2196
2197 class DetectScavengeRoot: public OopClosure {
2198 bool _detected_scavenge_root;
2199 public:
2200 DetectScavengeRoot() : _detected_scavenge_root(false)
2201 { NOT_PRODUCT(_print_nm = NULL); }
2202 bool detected_scavenge_root() { return _detected_scavenge_root; }
2203 virtual void do_oop(oop* p) {
2204 if ((*p) != NULL && (*p)->is_scavengable()) {
2205 NOT_PRODUCT(maybe_print(p));
2206 _detected_scavenge_root = true;
2207 }
2208 }
2209 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2210
2211 #ifndef PRODUCT
2212 nmethod* _print_nm;
2213 void maybe_print(oop* p) {
2214 if (_print_nm == NULL) return;
2215 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
2216 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
2217 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
2218 (void *)(*p), (intptr_t)p);
2219 (*p)->print();
2220 }
2221 #endif //PRODUCT
2222 };
2223
2224 bool nmethod::detect_scavenge_root_oops() {
2225 DetectScavengeRoot detect_scavenge_root;
2226 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
2227 oops_do(&detect_scavenge_root);
2228 return detect_scavenge_root.detected_scavenge_root();
2229 }
2230
2231 // Method that knows how to preserve outgoing arguments at call. This method must be
2232 // called with a frame corresponding to a Java invoke
2233 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
2234 #ifndef SHARK
2235 if (!method()->is_native()) {
2236 SimpleScopeDesc ssd(this, fr.pc());
2237 Bytecode_invoke call(ssd.method(), ssd.bci());
2238 bool has_receiver = call.has_receiver();
2239 bool has_appendix = call.has_appendix();
2240 Symbol* signature = call.signature();
2241 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
2242 }
2243 #endif // !SHARK
2244 }
2245
2246
2247 oop nmethod::embeddedOop_at(u_char* p) {
2248 RelocIterator iter(this, p, p + 1);
2249 while (iter.next())
2250 if (iter.type() == relocInfo::oop_type) {
2251 return iter.oop_reloc()->oop_value();
2252 }
2253 return NULL;
2254 }
2255
2256
2257 inline bool includes(void* p, void* from, void* to) {
2258 return from <= p && p < to;
2259 }
2260
2261
2262 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2263 assert(count >= 2, "must be sentinel values, at least");
2264
2265 #ifdef ASSERT
2266 // must be sorted and unique; we do a binary search in find_pc_desc()
2267 int prev_offset = pcs[0].pc_offset();
2268 assert(prev_offset == PcDesc::lower_offset_limit,
2269 "must start with a sentinel");
2270 for (int i = 1; i < count; i++) {
2271 int this_offset = pcs[i].pc_offset();
2272 assert(this_offset > prev_offset, "offsets must be sorted");
2273 prev_offset = this_offset;
2274 }
2275 assert(prev_offset == PcDesc::upper_offset_limit,
2276 "must end with a sentinel");
2277 #endif //ASSERT
2278
2279 // Search for MethodHandle invokes and tag the nmethod.
2280 for (int i = 0; i < count; i++) {
2281 if (pcs[i].is_method_handle_invoke()) {
2282 set_has_method_handle_invokes(true);
2283 break;
2284 }
2285 }
2286 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2287
2288 int size = count * sizeof(PcDesc);
2289 assert(scopes_pcs_size() >= size, "oob");
2290 memcpy(scopes_pcs_begin(), pcs, size);
2291
2292 // Adjust the final sentinel downward.
2293 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2294 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2295 last_pc->set_pc_offset(content_size() + 1);
2296 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2297 // Fill any rounding gaps with copies of the last record.
2298 last_pc[1] = last_pc[0];
2299 }
2300 // The following assert could fail if sizeof(PcDesc) is not
2301 // an integral multiple of oopSize (the rounding term).
2302 // If it fails, change the logic to always allocate a multiple
2303 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2304 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2305 }
2306
2307 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2308 assert(scopes_data_size() >= size, "oob");
2309 memcpy(scopes_data_begin(), buffer, size);
2310 }
2311
2312
2313 #ifdef ASSERT
2314 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2315 PcDesc* lower = nm->scopes_pcs_begin();
2316 PcDesc* upper = nm->scopes_pcs_end();
2317 lower += 1; // exclude initial sentinel
2318 PcDesc* res = NULL;
2319 for (PcDesc* p = lower; p < upper; p++) {
2320 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2321 if (match_desc(p, pc_offset, approximate)) {
2322 if (res == NULL)
2323 res = p;
2324 else
2325 res = (PcDesc*) badAddress;
2326 }
2327 }
2328 return res;
2329 }
2330 #endif
2331
2332
2333 // Finds a PcDesc with real-pc equal to "pc"
2334 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2335 address base_address = code_begin();
2336 if ((pc < base_address) ||
2337 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2338 return NULL; // PC is wildly out of range
2339 }
2340 int pc_offset = (int) (pc - base_address);
2341
2342 // Check the PcDesc cache if it contains the desired PcDesc
2343 // (This as an almost 100% hit rate.)
2344 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2345 if (res != NULL) {
2346 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2347 return res;
2348 }
2349
2350 // Fallback algorithm: quasi-linear search for the PcDesc
2351 // Find the last pc_offset less than the given offset.
2352 // The successor must be the required match, if there is a match at all.
2353 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2354 PcDesc* lower = scopes_pcs_begin();
2355 PcDesc* upper = scopes_pcs_end();
2356 upper -= 1; // exclude final sentinel
2357 if (lower >= upper) return NULL; // native method; no PcDescs at all
2358
2359 #define assert_LU_OK \
2360 /* invariant on lower..upper during the following search: */ \
2361 assert(lower->pc_offset() < pc_offset, "sanity"); \
2362 assert(upper->pc_offset() >= pc_offset, "sanity")
2363 assert_LU_OK;
2364
2365 // Use the last successful return as a split point.
2366 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2367 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2368 if (mid->pc_offset() < pc_offset) {
2369 lower = mid;
2370 } else {
2371 upper = mid;
2372 }
2373
2374 // Take giant steps at first (4096, then 256, then 16, then 1)
2375 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2376 const int RADIX = (1 << LOG2_RADIX);
2377 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2378 while ((mid = lower + step) < upper) {
2379 assert_LU_OK;
2380 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2381 if (mid->pc_offset() < pc_offset) {
2382 lower = mid;
2383 } else {
2384 upper = mid;
2385 break;
2386 }
2387 }
2388 assert_LU_OK;
2389 }
2390
2391 // Sneak up on the value with a linear search of length ~16.
2392 while (true) {
2393 assert_LU_OK;
2394 mid = lower + 1;
2395 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2396 if (mid->pc_offset() < pc_offset) {
2397 lower = mid;
2398 } else {
2399 upper = mid;
2400 break;
2401 }
2402 }
2403 #undef assert_LU_OK
2404
2405 if (match_desc(upper, pc_offset, approximate)) {
2406 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2407 _pc_desc_cache.add_pc_desc(upper);
2408 return upper;
2409 } else {
2410 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2411 return NULL;
2412 }
2413 }
2414
2415
2416 void nmethod::check_all_dependencies(DepChange& changes) {
2417 // Checked dependencies are allocated into this ResourceMark
2418 ResourceMark rm;
2419
2420 // Turn off dependency tracing while actually testing dependencies.
2421 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
2422
2423 typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
2424 &DependencySignature::equals, 11027> DepTable;
2425
2426 DepTable* table = new DepTable();
2427
2428 // Iterate over live nmethods and check dependencies of all nmethods that are not
2429 // marked for deoptimization. A particular dependency is only checked once.
2430 for(nmethod* nm = CodeCache::alive_nmethod(CodeCache::first()); nm != NULL; nm = CodeCache::alive_nmethod(CodeCache::next(nm))) {
2431 if (!nm->is_marked_for_deoptimization()) {
2432 for (Dependencies::DepStream deps(nm); deps.next(); ) {
2433 // Construct abstraction of a dependency.
2434 DependencySignature* current_sig = new DependencySignature(deps);
2435
2436 // Determine if dependency is already checked. table->put(...) returns
2437 // 'true' if the dependency is added (i.e., was not in the hashtable).
2438 if (table->put(*current_sig, 1)) {
2439 if (deps.check_dependency() != NULL) {
2440 // Dependency checking failed. Print out information about the failed
2441 // dependency and finally fail with an assert. We can fail here, since
2442 // dependency checking is never done in a product build.
2443 changes.print();
2444 nm->print();
2445 nm->print_dependencies();
2446 assert(false, "Should have been marked for deoptimization");
2447 }
2448 }
2449 }
2450 }
2451 }
2452 }
2453
2454 bool nmethod::check_dependency_on(DepChange& changes) {
2455 // What has happened:
2456 // 1) a new class dependee has been added
2457 // 2) dependee and all its super classes have been marked
2458 bool found_check = false; // set true if we are upset
2459 for (Dependencies::DepStream deps(this); deps.next(); ) {
2460 // Evaluate only relevant dependencies.
2461 if (deps.spot_check_dependency_at(changes) != NULL) {
2462 found_check = true;
2463 NOT_DEBUG(break);
2464 }
2465 }
2466 return found_check;
2467 }
2468
2469 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2470 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2471 Array<Method*>* dependee_methods = dependee_ik->methods();
2472 for (Dependencies::DepStream deps(this); deps.next(); ) {
2473 if (deps.type() == Dependencies::evol_method) {
2474 Method* method = deps.method_argument(0);
2475 for (int j = 0; j < dependee_methods->length(); j++) {
2476 if (dependee_methods->at(j) == method) {
2477 // RC_TRACE macro has an embedded ResourceMark
2478 RC_TRACE(0x01000000,
2479 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2480 _method->method_holder()->external_name(),
2481 _method->name()->as_C_string(),
2482 _method->signature()->as_C_string(), compile_id(),
2483 method->method_holder()->external_name(),
2484 method->name()->as_C_string(),
2485 method->signature()->as_C_string()));
2486 if (TraceDependencies || LogCompilation)
2487 deps.log_dependency(dependee);
2488 return true;
2489 }
2490 }
2491 }
2492 }
2493 return false;
2494 }
2495
2496 // Called from mark_for_deoptimization, when dependee is invalidated.
2497 bool nmethod::is_dependent_on_method(Method* dependee) {
2498 for (Dependencies::DepStream deps(this); deps.next(); ) {
2499 if (deps.type() != Dependencies::evol_method)
2500 continue;
2501 Method* method = deps.method_argument(0);
2502 if (method == dependee) return true;
2503 }
2504 return false;
2505 }
2506
2507
2508 bool nmethod::is_patchable_at(address instr_addr) {
2509 assert(insts_contains(instr_addr), "wrong nmethod used");
2510 if (is_zombie()) {
2511 // a zombie may never be patched
2512 return false;
2513 }
2514 return true;
2515 }
2516
2517
2518 address nmethod::continuation_for_implicit_exception(address pc) {
2519 // Exception happened outside inline-cache check code => we are inside
2520 // an active nmethod => use cpc to determine a return address
2521 int exception_offset = pc - code_begin();
2522 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2523 #ifdef ASSERT
2524 if (cont_offset == 0) {
2525 Thread* thread = ThreadLocalStorage::get_thread_slow();
2526 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2527 HandleMark hm(thread);
2528 ResourceMark rm(thread);
2529 CodeBlob* cb = CodeCache::find_blob(pc);
2530 assert(cb != NULL && cb == this, "");
2531 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2532 print();
2533 method()->print_codes();
2534 print_code();
2535 print_pcs();
2536 }
2537 #endif
2538 if (cont_offset == 0) {
2539 // Let the normal error handling report the exception
2540 return NULL;
2541 }
2542 return code_begin() + cont_offset;
2543 }
2544
2545
2546
2547 void nmethod_init() {
2548 // make sure you didn't forget to adjust the filler fields
2549 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2550 }
2551
2552
2553 //-------------------------------------------------------------------------------------------
2554
2555
2556 // QQQ might we make this work from a frame??
2557 nmethodLocker::nmethodLocker(address pc) {
2558 CodeBlob* cb = CodeCache::find_blob(pc);
2559 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2560 _nm = (nmethod*)cb;
2561 lock_nmethod(_nm);
2562 }
2563
2564 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2565 // should pass zombie_ok == true.
2566 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2567 if (nm == NULL) return;
2568 Atomic::inc(&nm->_lock_count);
2569 assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2570 }
2571
2572 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2573 if (nm == NULL) return;
2574 Atomic::dec(&nm->_lock_count);
2575 assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2576 }
2577
2578
2579 // -----------------------------------------------------------------------------
2580 // nmethod::get_deopt_original_pc
2581 //
2582 // Return the original PC for the given PC if:
2583 // (a) the given PC belongs to a nmethod and
2584 // (b) it is a deopt PC
2585 address nmethod::get_deopt_original_pc(const frame* fr) {
2586 if (fr->cb() == NULL) return NULL;
2587
2588 nmethod* nm = fr->cb()->as_nmethod_or_null();
2589 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2590 return nm->get_original_pc(fr);
2591
2592 return NULL;
2593 }
2594
2595
2596 // -----------------------------------------------------------------------------
2597 // MethodHandle
2598
2599 bool nmethod::is_method_handle_return(address return_pc) {
2600 if (!has_method_handle_invokes()) return false;
2601 PcDesc* pd = pc_desc_at(return_pc);
2602 if (pd == NULL)
2603 return false;
2604 return pd->is_method_handle_invoke();
2605 }
2606
2607
2608 // -----------------------------------------------------------------------------
2609 // Verification
2610
2611 class VerifyOopsClosure: public OopClosure {
2612 nmethod* _nm;
2613 bool _ok;
2614 public:
2615 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2616 bool ok() { return _ok; }
2617 virtual void do_oop(oop* p) {
2618 if ((*p) == NULL || (*p)->is_oop()) return;
2619 if (_ok) {
2620 _nm->print_nmethod(true);
2621 _ok = false;
2622 }
2623 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2624 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2625 }
2626 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2627 };
2628
2629 void nmethod::verify() {
2630
2631 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2632 // seems odd.
2633
2634 if( is_zombie() || is_not_entrant() )
2635 return;
2636
2637 // Make sure all the entry points are correctly aligned for patching.
2638 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2639
2640 // assert(method()->is_oop(), "must be valid");
2641
2642 ResourceMark rm;
2643
2644 if (!CodeCache::contains(this)) {
2645 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2646 }
2647
2648 if(is_native_method() )
2649 return;
2650
2651 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2652 if (nm != this) {
2653 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2654 this));
2655 }
2656
2657 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2658 if (! p->verify(this)) {
2659 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2660 }
2661 }
2662
2663 VerifyOopsClosure voc(this);
2664 oops_do(&voc);
2665 assert(voc.ok(), "embedded oops must be OK");
2666 verify_scavenge_root_oops();
2667
2668 verify_scopes();
2669 }
2670
2671
2672 void nmethod::verify_interrupt_point(address call_site) {
2673 // Verify IC only when nmethod installation is finished.
2674 bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed
2675 || !this->is_in_use(); // nmethod is installed, but not in 'in_use' state
2676 if (is_installed) {
2677 Thread *cur = Thread::current();
2678 if (CompiledIC_lock->owner() == cur ||
2679 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2680 SafepointSynchronize::is_at_safepoint())) {
2681 CompiledIC_at(this, call_site);
2682 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2683 } else {
2684 MutexLocker ml_verify (CompiledIC_lock);
2685 CompiledIC_at(this, call_site);
2686 }
2687 }
2688
2689 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2690 assert(pd != NULL, "PcDesc must exist");
2691 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2692 pd->obj_decode_offset(), pd->should_reexecute(),
2693 pd->return_oop());
2694 !sd->is_top(); sd = sd->sender()) {
2695 sd->verify();
2696 }
2697 }
2698
2699 void nmethod::verify_scopes() {
2700 if( !method() ) return; // Runtime stubs have no scope
2701 if (method()->is_native()) return; // Ignore stub methods.
2702 // iterate through all interrupt point
2703 // and verify the debug information is valid.
2704 RelocIterator iter((nmethod*)this);
2705 while (iter.next()) {
2706 address stub = NULL;
2707 switch (iter.type()) {
2708 case relocInfo::virtual_call_type:
2709 verify_interrupt_point(iter.addr());
2710 break;
2711 case relocInfo::opt_virtual_call_type:
2712 stub = iter.opt_virtual_call_reloc()->static_stub();
2713 verify_interrupt_point(iter.addr());
2714 break;
2715 case relocInfo::static_call_type:
2716 stub = iter.static_call_reloc()->static_stub();
2717 //verify_interrupt_point(iter.addr());
2718 break;
2719 case relocInfo::runtime_call_type:
2720 address destination = iter.reloc()->value();
2721 // Right now there is no way to find out which entries support
2722 // an interrupt point. It would be nice if we had this
2723 // information in a table.
2724 break;
2725 }
2726 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2727 }
2728 }
2729
2730
2731 // -----------------------------------------------------------------------------
2732 // Non-product code
2733 #ifndef PRODUCT
2734
2735 class DebugScavengeRoot: public OopClosure {
2736 nmethod* _nm;
2737 bool _ok;
2738 public:
2739 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2740 bool ok() { return _ok; }
2741 virtual void do_oop(oop* p) {
2742 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2743 if (_ok) {
2744 _nm->print_nmethod(true);
2745 _ok = false;
2746 }
2747 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2748 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2749 (*p)->print();
2750 }
2751 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2752 };
2753
2754 void nmethod::verify_scavenge_root_oops() {
2755 if (UseG1GC) {
2756 return;
2757 }
2758
2759 if (!on_scavenge_root_list()) {
2760 // Actually look inside, to verify the claim that it's clean.
2761 DebugScavengeRoot debug_scavenge_root(this);
2762 oops_do(&debug_scavenge_root);
2763 if (!debug_scavenge_root.ok())
2764 fatal("found an unadvertised bad scavengable oop in the code cache");
2765 }
2766 assert(scavenge_root_not_marked(), "");
2767 }
2768
2769 #endif // PRODUCT
2770
2771 // Printing operations
2772
2773 void nmethod::print() const {
2774 ResourceMark rm;
2775 ttyLocker ttyl; // keep the following output all in one block
2776
2777 tty->print("Compiled method ");
2778
2779 if (is_compiled_by_c1()) {
2780 tty->print("(c1) ");
2781 } else if (is_compiled_by_c2()) {
2782 tty->print("(c2) ");
2783 } else if (is_compiled_by_shark()) {
2784 tty->print("(shark) ");
2785 } else {
2786 tty->print("(nm) ");
2787 }
2788
2789 print_on(tty, NULL);
2790
2791 if (WizardMode) {
2792 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2793 tty->print(" for method " INTPTR_FORMAT , (address)method());
2794 tty->print(" { ");
2795 if (is_in_use()) tty->print("in_use ");
2796 if (is_not_entrant()) tty->print("not_entrant ");
2797 if (is_zombie()) tty->print("zombie ");
2798 if (is_unloaded()) tty->print("unloaded ");
2799 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2800 tty->print_cr("}:");
2801 }
2802 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2803 (address)this,
2804 (address)this + size(),
2805 size());
2806 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2807 relocation_begin(),
2808 relocation_end(),
2809 relocation_size());
2810 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2811 consts_begin(),
2812 consts_end(),
2813 consts_size());
2814 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2815 insts_begin(),
2816 insts_end(),
2817 insts_size());
2818 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2819 stub_begin(),
2820 stub_end(),
2821 stub_size());
2822 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2823 oops_begin(),
2824 oops_end(),
2825 oops_size());
2826 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2827 metadata_begin(),
2828 metadata_end(),
2829 metadata_size());
2830 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2831 scopes_data_begin(),
2832 scopes_data_end(),
2833 scopes_data_size());
2834 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2835 scopes_pcs_begin(),
2836 scopes_pcs_end(),
2837 scopes_pcs_size());
2838 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2839 dependencies_begin(),
2840 dependencies_end(),
2841 dependencies_size());
2842 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2843 handler_table_begin(),
2844 handler_table_end(),
2845 handler_table_size());
2846 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2847 nul_chk_table_begin(),
2848 nul_chk_table_end(),
2849 nul_chk_table_size());
2850 }
2851
2852 void nmethod::print_code() {
2853 HandleMark hm;
2854 ResourceMark m;
2855 Disassembler::decode(this);
2856 }
2857
2858
2859 #ifndef PRODUCT
2860
2861 void nmethod::print_scopes() {
2862 // Find the first pc desc for all scopes in the code and print it.
2863 ResourceMark rm;
2864 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2865 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2866 continue;
2867
2868 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2869 sd->print_on(tty, p);
2870 }
2871 }
2872
2873 void nmethod::print_dependencies() {
2874 ResourceMark rm;
2875 ttyLocker ttyl; // keep the following output all in one block
2876 tty->print_cr("Dependencies:");
2877 for (Dependencies::DepStream deps(this); deps.next(); ) {
2878 deps.print_dependency();
2879 Klass* ctxk = deps.context_type();
2880 if (ctxk != NULL) {
2881 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2882 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2883 }
2884 }
2885 deps.log_dependency(); // put it into the xml log also
2886 }
2887 }
2888
2889
2890 void nmethod::print_relocations() {
2891 ResourceMark m; // in case methods get printed via the debugger
2892 tty->print_cr("relocations:");
2893 RelocIterator iter(this);
2894 iter.print();
2895 if (UseRelocIndex) {
2896 jint* index_end = (jint*)relocation_end() - 1;
2897 jint index_size = *index_end;
2898 jint* index_start = (jint*)( (address)index_end - index_size );
2899 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2900 if (index_size > 0) {
2901 jint* ip;
2902 for (ip = index_start; ip+2 <= index_end; ip += 2)
2903 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2904 ip[0],
2905 ip[1],
2906 header_end()+ip[0],
2907 relocation_begin()-1+ip[1]);
2908 for (; ip < index_end; ip++)
2909 tty->print_cr(" (%d ?)", ip[0]);
2910 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip);
2911 ip++;
2912 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2913 }
2914 }
2915 }
2916
2917
2918 void nmethod::print_pcs() {
2919 ResourceMark m; // in case methods get printed via debugger
2920 tty->print_cr("pc-bytecode offsets:");
2921 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2922 p->print(this);
2923 }
2924 }
2925
2926 #endif // PRODUCT
2927
2928 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2929 RelocIterator iter(this, begin, end);
2930 bool have_one = false;
2931 while (iter.next()) {
2932 have_one = true;
2933 switch (iter.type()) {
2934 case relocInfo::none: return "no_reloc";
2935 case relocInfo::oop_type: {
2936 stringStream st;
2937 oop_Relocation* r = iter.oop_reloc();
2938 oop obj = r->oop_value();
2939 st.print("oop(");
2940 if (obj == NULL) st.print("NULL");
2941 else obj->print_value_on(&st);
2942 st.print(")");
2943 return st.as_string();
2944 }
2945 case relocInfo::metadata_type: {
2946 stringStream st;
2947 metadata_Relocation* r = iter.metadata_reloc();
2948 Metadata* obj = r->metadata_value();
2949 st.print("metadata(");
2950 if (obj == NULL) st.print("NULL");
2951 else obj->print_value_on(&st);
2952 st.print(")");
2953 return st.as_string();
2954 }
2955 case relocInfo::virtual_call_type: return "virtual_call";
2956 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2957 case relocInfo::static_call_type: return "static_call";
2958 case relocInfo::static_stub_type: return "static_stub";
2959 case relocInfo::runtime_call_type: return "runtime_call";
2960 case relocInfo::external_word_type: return "external_word";
2961 case relocInfo::internal_word_type: return "internal_word";
2962 case relocInfo::section_word_type: return "section_word";
2963 case relocInfo::poll_type: return "poll";
2964 case relocInfo::poll_return_type: return "poll_return";
2965 case relocInfo::type_mask: return "type_bit_mask";
2966 }
2967 }
2968 return have_one ? "other" : NULL;
2969 }
2970
2971 // Return a the last scope in (begin..end]
2972 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2973 PcDesc* p = pc_desc_near(begin+1);
2974 if (p != NULL && p->real_pc(this) <= end) {
2975 return new ScopeDesc(this, p->scope_decode_offset(),
2976 p->obj_decode_offset(), p->should_reexecute(),
2977 p->return_oop());
2978 }
2979 return NULL;
2980 }
2981
2982 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2983 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2984 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2985 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2986 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2987 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2988
2989 if (has_method_handle_invokes())
2990 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
2991
2992 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
2993
2994 if (block_begin == entry_point()) {
2995 methodHandle m = method();
2996 if (m.not_null()) {
2997 stream->print(" # ");
2998 m->print_value_on(stream);
2999 stream->cr();
3000 }
3001 if (m.not_null() && !is_osr_method()) {
3002 ResourceMark rm;
3003 int sizeargs = m->size_of_parameters();
3004 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
3005 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
3006 {
3007 int sig_index = 0;
3008 if (!m->is_static())
3009 sig_bt[sig_index++] = T_OBJECT; // 'this'
3010 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
3011 BasicType t = ss.type();
3012 sig_bt[sig_index++] = t;
3013 if (type2size[t] == 2) {
3014 sig_bt[sig_index++] = T_VOID;
3015 } else {
3016 assert(type2size[t] == 1, "size is 1 or 2");
3017 }
3018 }
3019 assert(sig_index == sizeargs, "");
3020 }
3021 const char* spname = "sp"; // make arch-specific?
3022 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
3023 int stack_slot_offset = this->frame_size() * wordSize;
3024 int tab1 = 14, tab2 = 24;
3025 int sig_index = 0;
3026 int arg_index = (m->is_static() ? 0 : -1);
3027 bool did_old_sp = false;
3028 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
3029 bool at_this = (arg_index == -1);
3030 bool at_old_sp = false;
3031 BasicType t = (at_this ? T_OBJECT : ss.type());
3032 assert(t == sig_bt[sig_index], "sigs in sync");
3033 if (at_this)
3034 stream->print(" # this: ");
3035 else
3036 stream->print(" # parm%d: ", arg_index);
3037 stream->move_to(tab1);
3038 VMReg fst = regs[sig_index].first();
3039 VMReg snd = regs[sig_index].second();
3040 if (fst->is_reg()) {
3041 stream->print("%s", fst->name());
3042 if (snd->is_valid()) {
3043 stream->print(":%s", snd->name());
3044 }
3045 } else if (fst->is_stack()) {
3046 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
3047 if (offset == stack_slot_offset) at_old_sp = true;
3048 stream->print("[%s+0x%x]", spname, offset);
3049 } else {
3050 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
3051 }
3052 stream->print(" ");
3053 stream->move_to(tab2);
3054 stream->print("= ");
3055 if (at_this) {
3056 m->method_holder()->print_value_on(stream);
3057 } else {
3058 bool did_name = false;
3059 if (!at_this && ss.is_object()) {
3060 Symbol* name = ss.as_symbol_or_null();
3061 if (name != NULL) {
3062 name->print_value_on(stream);
3063 did_name = true;
3064 }
3065 }
3066 if (!did_name)
3067 stream->print("%s", type2name(t));
3068 }
3069 if (at_old_sp) {
3070 stream->print(" (%s of caller)", spname);
3071 did_old_sp = true;
3072 }
3073 stream->cr();
3074 sig_index += type2size[t];
3075 arg_index += 1;
3076 if (!at_this) ss.next();
3077 }
3078 if (!did_old_sp) {
3079 stream->print(" # ");
3080 stream->move_to(tab1);
3081 stream->print("[%s+0x%x]", spname, stack_slot_offset);
3082 stream->print(" (%s of caller)", spname);
3083 stream->cr();
3084 }
3085 }
3086 }
3087 }
3088
3089 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
3090 // First, find an oopmap in (begin, end].
3091 // We use the odd half-closed interval so that oop maps and scope descs
3092 // which are tied to the byte after a call are printed with the call itself.
3093 address base = code_begin();
3094 OopMapSet* oms = oop_maps();
3095 if (oms != NULL) {
3096 for (int i = 0, imax = oms->size(); i < imax; i++) {
3097 OopMap* om = oms->at(i);
3098 address pc = base + om->offset();
3099 if (pc > begin) {
3100 if (pc <= end) {
3101 st->move_to(column);
3102 st->print("; ");
3103 om->print_on(st);
3104 }
3105 break;
3106 }
3107 }
3108 }
3109
3110 // Print any debug info present at this pc.
3111 ScopeDesc* sd = scope_desc_in(begin, end);
3112 if (sd != NULL) {
3113 st->move_to(column);
3114 if (sd->bci() == SynchronizationEntryBCI) {
3115 st->print(";*synchronization entry");
3116 } else {
3117 if (sd->method() == NULL) {
3118 st->print("method is NULL");
3119 } else if (sd->method()->is_native()) {
3120 st->print("method is native");
3121 } else {
3122 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
3123 st->print(";*%s", Bytecodes::name(bc));
3124 switch (bc) {
3125 case Bytecodes::_invokevirtual:
3126 case Bytecodes::_invokespecial:
3127 case Bytecodes::_invokestatic:
3128 case Bytecodes::_invokeinterface:
3129 {
3130 Bytecode_invoke invoke(sd->method(), sd->bci());
3131 st->print(" ");
3132 if (invoke.name() != NULL)
3133 invoke.name()->print_symbol_on(st);
3134 else
3135 st->print("<UNKNOWN>");
3136 break;
3137 }
3138 case Bytecodes::_getfield:
3139 case Bytecodes::_putfield:
3140 case Bytecodes::_getstatic:
3141 case Bytecodes::_putstatic:
3142 {
3143 Bytecode_field field(sd->method(), sd->bci());
3144 st->print(" ");
3145 if (field.name() != NULL)
3146 field.name()->print_symbol_on(st);
3147 else
3148 st->print("<UNKNOWN>");
3149 }
3150 }
3151 }
3152 }
3153
3154 // Print all scopes
3155 for (;sd != NULL; sd = sd->sender()) {
3156 st->move_to(column);
3157 st->print("; -");
3158 if (sd->method() == NULL) {
3159 st->print("method is NULL");
3160 } else {
3161 sd->method()->print_short_name(st);
3162 }
3163 int lineno = sd->method()->line_number_from_bci(sd->bci());
3164 if (lineno != -1) {
3165 st->print("@%d (line %d)", sd->bci(), lineno);
3166 } else {
3167 st->print("@%d", sd->bci());
3168 }
3169 st->cr();
3170 }
3171 }
3172
3173 // Print relocation information
3174 const char* str = reloc_string_for(begin, end);
3175 if (str != NULL) {
3176 if (sd != NULL) st->cr();
3177 st->move_to(column);
3178 st->print("; {%s}", str);
3179 }
3180 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
3181 if (cont_offset != 0) {
3182 st->move_to(column);
3183 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
3184 }
3185
3186 }
3187
3188 #ifndef PRODUCT
3189
3190 void nmethod::print_value_on(outputStream* st) const {
3191 st->print("nmethod");
3192 print_on(st, NULL);
3193 }
3194
3195 void nmethod::print_calls(outputStream* st) {
3196 RelocIterator iter(this);
3197 while (iter.next()) {
3198 switch (iter.type()) {
3199 case relocInfo::virtual_call_type:
3200 case relocInfo::opt_virtual_call_type: {
3201 VerifyMutexLocker mc(CompiledIC_lock);
3202 CompiledIC_at(&iter)->print();
3203 break;
3204 }
3205 case relocInfo::static_call_type:
3206 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
3207 compiledStaticCall_at(iter.reloc())->print();
3208 break;
3209 }
3210 }
3211 }
3212
3213 void nmethod::print_handler_table() {
3214 ExceptionHandlerTable(this).print();
3215 }
3216
3217 void nmethod::print_nul_chk_table() {
3218 ImplicitExceptionTable(this).print(code_begin());
3219 }
3220
3221 void nmethod::print_statistics() {
3222 ttyLocker ttyl;
3223 if (xtty != NULL) xtty->head("statistics type='nmethod'");
3224 nmethod_stats.print_native_nmethod_stats();
3225 nmethod_stats.print_nmethod_stats();
3226 DebugInformationRecorder::print_statistics();
3227 nmethod_stats.print_pc_stats();
3228 Dependencies::print_statistics();
3229 if (xtty != NULL) xtty->tail("statistics");
3230 }
3231
3232 #endif // PRODUCT