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 "oops/oop.inline.hpp"
39 #include "prims/jvmtiRedefineClassesTrace.hpp"
40 #include "prims/jvmtiImpl.hpp"
41 #include "runtime/atomic.inline.hpp"
42 #include "runtime/orderAccess.inline.hpp"
43 #include "runtime/sharedRuntime.hpp"
44 #include "runtime/sweeper.hpp"
45 #include "utilities/resourceHash.hpp"
46 #include "utilities/dtrace.hpp"
47 #include "utilities/events.hpp"
48 #include "utilities/xmlstream.hpp"
49 #ifdef SHARK
50 #include "shark/sharkCompiler.hpp"
51 #endif
52
53 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
54
55 unsigned char nmethod::_global_unloading_clock = 0;
56
57 #ifdef DTRACE_ENABLED
58
59 // Only bother with this argument setup if dtrace is available
60
61 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
62 { \
63 Method* m = (method); \
64 if (m != NULL) { \
65 Symbol* klass_name = m->klass_name(); \
66 Symbol* name = m->name(); \
67 Symbol* signature = m->signature(); \
68 HOTSPOT_COMPILED_METHOD_UNLOAD( \
69 (char *) klass_name->bytes(), klass_name->utf8_length(), \
70 (char *) name->bytes(), name->utf8_length(), \
71 (char *) signature->bytes(), signature->utf8_length()); \
72 } \
73 }
74
75 #else // ndef DTRACE_ENABLED
76
77 #define DTRACE_METHOD_UNLOAD_PROBE(method)
78
79 #endif
80
81 bool nmethod::is_compiled_by_c1() const {
82 if (compiler() == NULL) {
83 return false;
84 }
85 return compiler()->is_c1();
86 }
87 bool nmethod::is_compiled_by_c2() const {
88 if (compiler() == NULL) {
89 return false;
90 }
91 return compiler()->is_c2();
92 }
93 bool nmethod::is_compiled_by_shark() const {
94 if (compiler() == NULL) {
95 return false;
96 }
97 return compiler()->is_shark();
98 }
99
100
101
102 //---------------------------------------------------------------------------------
103 // NMethod statistics
104 // They are printed under various flags, including:
105 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
106 // (In the latter two cases, they like other stats are printed to the log only.)
107
108 #ifndef PRODUCT
109 // These variables are put into one block to reduce relocations
110 // and make it simpler to print from the debugger.
111 static
112 struct nmethod_stats_struct {
113 int nmethod_count;
114 int total_size;
115 int relocation_size;
116 int consts_size;
117 int insts_size;
118 int stub_size;
119 int scopes_data_size;
120 int scopes_pcs_size;
121 int dependencies_size;
122 int handler_table_size;
123 int nul_chk_table_size;
124 int oops_size;
125
126 void note_nmethod(nmethod* nm) {
127 nmethod_count += 1;
128 total_size += nm->size();
129 relocation_size += nm->relocation_size();
130 consts_size += nm->consts_size();
131 insts_size += nm->insts_size();
132 stub_size += nm->stub_size();
133 oops_size += nm->oops_size();
134 scopes_data_size += nm->scopes_data_size();
135 scopes_pcs_size += nm->scopes_pcs_size();
136 dependencies_size += nm->dependencies_size();
137 handler_table_size += nm->handler_table_size();
138 nul_chk_table_size += nm->nul_chk_table_size();
139 }
140 void print_nmethod_stats() {
141 if (nmethod_count == 0) return;
142 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
143 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
144 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
145 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
146 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size);
147 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
148 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
149 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
150 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
151 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
152 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
153 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
154 }
155
156 int native_nmethod_count;
157 int native_total_size;
158 int native_relocation_size;
159 int native_insts_size;
160 int native_oops_size;
161 void note_native_nmethod(nmethod* nm) {
162 native_nmethod_count += 1;
163 native_total_size += nm->size();
164 native_relocation_size += nm->relocation_size();
165 native_insts_size += nm->insts_size();
166 native_oops_size += nm->oops_size();
167 }
168 void print_native_nmethod_stats() {
169 if (native_nmethod_count == 0) return;
170 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
171 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
172 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
173 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size);
174 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
175 }
176
177 int pc_desc_resets; // number of resets (= number of caches)
178 int pc_desc_queries; // queries to nmethod::find_pc_desc
179 int pc_desc_approx; // number of those which have approximate true
180 int pc_desc_repeats; // number of _pc_descs[0] hits
181 int pc_desc_hits; // number of LRU cache hits
182 int pc_desc_tests; // total number of PcDesc examinations
183 int pc_desc_searches; // total number of quasi-binary search steps
184 int pc_desc_adds; // number of LUR cache insertions
185
186 void print_pc_stats() {
187 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
188 pc_desc_queries,
189 (double)(pc_desc_tests + pc_desc_searches)
190 / pc_desc_queries);
191 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
192 pc_desc_resets,
193 pc_desc_queries, pc_desc_approx,
194 pc_desc_repeats, pc_desc_hits,
195 pc_desc_tests, pc_desc_searches, pc_desc_adds);
196 }
197 } nmethod_stats;
198 #endif //PRODUCT
199
200
201 //---------------------------------------------------------------------------------
202
203
204 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
205 assert(pc != NULL, "Must be non null");
206 assert(exception.not_null(), "Must be non null");
207 assert(handler != NULL, "Must be non null");
208
209 _count = 0;
210 _exception_type = exception->klass();
211 _next = NULL;
212
213 add_address_and_handler(pc,handler);
214 }
215
216
217 address ExceptionCache::match(Handle exception, address pc) {
218 assert(pc != NULL,"Must be non null");
219 assert(exception.not_null(),"Must be non null");
220 if (exception->klass() == exception_type()) {
221 return (test_address(pc));
222 }
223
224 return NULL;
225 }
226
227
228 bool ExceptionCache::match_exception_with_space(Handle exception) {
229 assert(exception.not_null(),"Must be non null");
230 if (exception->klass() == exception_type() && count() < cache_size) {
231 return true;
232 }
233 return false;
234 }
235
236
237 address ExceptionCache::test_address(address addr) {
238 for (int i=0; i<count(); i++) {
239 if (pc_at(i) == addr) {
240 return handler_at(i);
241 }
242 }
243 return NULL;
244 }
245
246
247 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
248 if (test_address(addr) == handler) return true;
249 if (count() < cache_size) {
250 set_pc_at(count(),addr);
251 set_handler_at(count(), handler);
252 increment_count();
253 return true;
254 }
255 return false;
256 }
257
258
259 // private method for handling exception cache
260 // These methods are private, and used to manipulate the exception cache
261 // directly.
262 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
263 ExceptionCache* ec = exception_cache();
264 while (ec != NULL) {
265 if (ec->match_exception_with_space(exception)) {
266 return ec;
267 }
268 ec = ec->next();
269 }
270 return NULL;
271 }
272
273
274 //-----------------------------------------------------------------------------
275
276
277 // Helper used by both find_pc_desc methods.
278 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
279 NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
280 if (!approximate)
281 return pc->pc_offset() == pc_offset;
282 else
283 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
284 }
285
286 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
287 if (initial_pc_desc == NULL) {
288 _pc_descs[0] = NULL; // native method; no PcDescs at all
289 return;
290 }
291 NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
292 // reset the cache by filling it with benign (non-null) values
293 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
294 for (int i = 0; i < cache_size; i++)
295 _pc_descs[i] = initial_pc_desc;
296 }
297
298 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
299 NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
300 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
301
302 // Note: one might think that caching the most recently
303 // read value separately would be a win, but one would be
304 // wrong. When many threads are updating it, the cache
305 // line it's in would bounce between caches, negating
306 // any benefit.
307
308 // In order to prevent race conditions do not load cache elements
309 // repeatedly, but use a local copy:
310 PcDesc* res;
311
312 // Step one: Check the most recently added value.
313 res = _pc_descs[0];
314 if (res == NULL) return NULL; // native method; no PcDescs at all
315 if (match_desc(res, pc_offset, approximate)) {
316 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
317 return res;
318 }
319
320 // Step two: Check the rest of the LRU cache.
321 for (int i = 1; i < cache_size; ++i) {
322 res = _pc_descs[i];
323 if (res->pc_offset() < 0) break; // optimization: skip empty cache
324 if (match_desc(res, pc_offset, approximate)) {
325 NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
326 return res;
327 }
328 }
329
330 // Report failure.
331 return NULL;
332 }
333
334 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
335 NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
336 // Update the LRU cache by shifting pc_desc forward.
337 for (int i = 0; i < cache_size; i++) {
338 PcDesc* next = _pc_descs[i];
339 _pc_descs[i] = pc_desc;
340 pc_desc = next;
341 }
342 }
343
344 // adjust pcs_size so that it is a multiple of both oopSize and
345 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
346 // of oopSize, then 2*sizeof(PcDesc) is)
347 static int adjust_pcs_size(int pcs_size) {
348 int nsize = round_to(pcs_size, oopSize);
349 if ((nsize % sizeof(PcDesc)) != 0) {
350 nsize = pcs_size + sizeof(PcDesc);
351 }
352 assert((nsize % oopSize) == 0, "correct alignment");
353 return nsize;
354 }
355
356 //-----------------------------------------------------------------------------
357
358
359 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
360 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
361 assert(new_entry != NULL,"Must be non null");
362 assert(new_entry->next() == NULL, "Must be null");
363
364 if (exception_cache() != NULL) {
365 new_entry->set_next(exception_cache());
366 }
367 set_exception_cache(new_entry);
368 }
369
370 void nmethod::clean_exception_cache(BoolObjectClosure* is_alive) {
371 ExceptionCache* prev = NULL;
372 ExceptionCache* curr = exception_cache();
373
374 while (curr != NULL) {
375 ExceptionCache* next = curr->next();
376
377 Klass* ex_klass = curr->exception_type();
378 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
379 if (prev == NULL) {
380 set_exception_cache(next);
381 } else {
382 prev->set_next(next);
383 }
384 delete curr;
385 // prev stays the same.
386 } else {
387 prev = curr;
388 }
389
390 curr = next;
391 }
392 }
393
394 // public method for accessing the exception cache
395 // These are the public access methods.
396 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
397 // We never grab a lock to read the exception cache, so we may
398 // have false negatives. This is okay, as it can only happen during
399 // the first few exception lookups for a given nmethod.
400 ExceptionCache* ec = exception_cache();
401 while (ec != NULL) {
402 address ret_val;
403 if ((ret_val = ec->match(exception,pc)) != NULL) {
404 return ret_val;
405 }
406 ec = ec->next();
407 }
408 return NULL;
409 }
410
411
412 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
413 // There are potential race conditions during exception cache updates, so we
414 // must own the ExceptionCache_lock before doing ANY modifications. Because
415 // we don't lock during reads, it is possible to have several threads attempt
416 // to update the cache with the same data. We need to check for already inserted
417 // copies of the current data before adding it.
418
419 MutexLocker ml(ExceptionCache_lock);
420 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
421
422 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
423 target_entry = new ExceptionCache(exception,pc,handler);
424 add_exception_cache_entry(target_entry);
425 }
426 }
427
428
429 //-------------end of code for ExceptionCache--------------
430
431
432 int nmethod::total_size() const {
433 return
434 consts_size() +
435 insts_size() +
436 stub_size() +
437 scopes_data_size() +
438 scopes_pcs_size() +
439 handler_table_size() +
440 nul_chk_table_size();
441 }
442
443 const char* nmethod::compile_kind() const {
444 if (is_osr_method()) return "osr";
445 if (method() != NULL && is_native_method()) return "c2n";
446 return NULL;
447 }
448
449 // Fill in default values for various flag fields
450 void nmethod::init_defaults() {
451 _state = in_use;
452 _unloading_clock = 0;
453 _marked_for_reclamation = 0;
454 _has_flushed_dependencies = 0;
455 _has_unsafe_access = 0;
456 _has_method_handle_invokes = 0;
457 _lazy_critical_native = 0;
458 _has_wide_vectors = 0;
459 _marked_for_deoptimization = 0;
460 _lock_count = 0;
461 _stack_traversal_mark = 0;
462 _unload_reported = false; // jvmti state
463
464 #ifdef ASSERT
465 _oops_are_stale = false;
466 #endif
467
468 _oops_do_mark_link = NULL;
469 _jmethod_id = NULL;
470 _osr_link = NULL;
471 if (UseG1GC) {
472 _unloading_next = NULL;
473 } else {
474 _scavenge_root_link = NULL;
475 }
476 _scavenge_root_state = 0;
477 _compiler = NULL;
478 #if INCLUDE_RTM_OPT
479 _rtm_state = NoRTM;
480 #endif
481 #ifdef HAVE_DTRACE_H
482 _trap_offset = 0;
483 #endif // def HAVE_DTRACE_H
484 }
485
486 nmethod* nmethod::new_native_nmethod(methodHandle method,
487 int compile_id,
488 CodeBuffer *code_buffer,
489 int vep_offset,
490 int frame_complete,
491 int frame_size,
492 ByteSize basic_lock_owner_sp_offset,
493 ByteSize basic_lock_sp_offset,
494 OopMapSet* oop_maps) {
495 code_buffer->finalize_oop_references(method);
496 // create nmethod
497 nmethod* nm = NULL;
498 {
499 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
500 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
501 CodeOffsets offsets;
502 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
503 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
504 nm = new (native_nmethod_size, CompLevel_none) nmethod(method(), native_nmethod_size,
505 compile_id, &offsets,
506 code_buffer, frame_size,
507 basic_lock_owner_sp_offset,
508 basic_lock_sp_offset, oop_maps);
509 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm));
510 if (PrintAssembly && nm != NULL) {
511 Disassembler::decode(nm);
512 }
513 }
514 // verify nmethod
515 debug_only(if (nm) nm->verify();) // might block
516
517 if (nm != NULL) {
518 nm->log_new_nmethod();
519 }
520
521 return nm;
522 }
523
524 #ifdef HAVE_DTRACE_H
525 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
526 CodeBuffer *code_buffer,
527 int vep_offset,
528 int trap_offset,
529 int frame_complete,
530 int frame_size) {
531 code_buffer->finalize_oop_references(method);
532 // create nmethod
533 nmethod* nm = NULL;
534 {
535 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
536 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
537 CodeOffsets offsets;
538 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
539 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
540 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
541
542 nm = new (nmethod_size, CompLevel_none) nmethod(method(), nmethod_size,
543 &offsets, code_buffer, frame_size);
544
545 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
546 if (PrintAssembly && nm != NULL) {
547 Disassembler::decode(nm);
548 }
549 }
550 // verify nmethod
551 debug_only(if (nm) nm->verify();) // might block
552
553 if (nm != NULL) {
554 nm->log_new_nmethod();
555 }
556
557 return nm;
558 }
559
560 #endif // def HAVE_DTRACE_H
561
562 nmethod* nmethod::new_nmethod(methodHandle method,
563 int compile_id,
564 int entry_bci,
565 CodeOffsets* offsets,
566 int orig_pc_offset,
567 DebugInformationRecorder* debug_info,
568 Dependencies* dependencies,
569 CodeBuffer* code_buffer, int frame_size,
570 OopMapSet* oop_maps,
571 ExceptionHandlerTable* handler_table,
572 ImplicitExceptionTable* nul_chk_table,
573 AbstractCompiler* compiler,
574 int comp_level
575 )
576 {
577 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
578 code_buffer->finalize_oop_references(method);
579 // create nmethod
580 nmethod* nm = NULL;
581 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
582 int nmethod_size =
583 allocation_size(code_buffer, sizeof(nmethod))
584 + adjust_pcs_size(debug_info->pcs_size())
585 + round_to(dependencies->size_in_bytes() , oopSize)
586 + round_to(handler_table->size_in_bytes(), oopSize)
587 + round_to(nul_chk_table->size_in_bytes(), oopSize)
588 + round_to(debug_info->data_size() , oopSize);
589
590 nm = new (nmethod_size, comp_level)
591 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
592 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
593 oop_maps,
594 handler_table,
595 nul_chk_table,
596 compiler,
597 comp_level);
598
599 if (nm != NULL) {
600 // To make dependency checking during class loading fast, record
601 // the nmethod dependencies in the classes it is dependent on.
602 // This allows the dependency checking code to simply walk the
603 // class hierarchy above the loaded class, checking only nmethods
604 // which are dependent on those classes. The slow way is to
605 // check every nmethod for dependencies which makes it linear in
606 // the number of methods compiled. For applications with a lot
607 // classes the slow way is too slow.
608 for (Dependencies::DepStream deps(nm); deps.next(); ) {
609 Klass* klass = deps.context_type();
610 if (klass == NULL) {
611 continue; // ignore things like evol_method
612 }
613
614 // record this nmethod as dependent on this klass
615 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
616 }
617 NOT_PRODUCT(nmethod_stats.note_nmethod(nm));
618 if (PrintAssembly || CompilerOracle::has_option_string(method, "PrintAssembly")) {
619 Disassembler::decode(nm);
620 }
621 }
622 }
623 // Do verification and logging outside CodeCache_lock.
624 if (nm != NULL) {
625 // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
626 DEBUG_ONLY(nm->verify();)
627 nm->log_new_nmethod();
628 }
629 return nm;
630 }
631
632
633 // For native wrappers
634 nmethod::nmethod(
635 Method* method,
636 int nmethod_size,
637 int compile_id,
638 CodeOffsets* offsets,
639 CodeBuffer* code_buffer,
640 int frame_size,
641 ByteSize basic_lock_owner_sp_offset,
642 ByteSize basic_lock_sp_offset,
643 OopMapSet* oop_maps )
644 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
645 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
646 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
647 _native_basic_lock_sp_offset(basic_lock_sp_offset)
648 {
649 {
650 debug_only(No_Safepoint_Verifier nsv;)
651 assert_locked_or_safepoint(CodeCache_lock);
652
653 init_defaults();
654 _method = method;
655 _entry_bci = InvocationEntryBci;
656 // We have no exception handler or deopt handler make the
657 // values something that will never match a pc like the nmethod vtable entry
658 _exception_offset = 0;
659 _deoptimize_offset = 0;
660 _deoptimize_mh_offset = 0;
661 _orig_pc_offset = 0;
662
663 _consts_offset = data_offset();
664 _stub_offset = data_offset();
665 _oops_offset = data_offset();
666 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
667 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
668 _scopes_pcs_offset = _scopes_data_offset;
669 _dependencies_offset = _scopes_pcs_offset;
670 _handler_table_offset = _dependencies_offset;
671 _nul_chk_table_offset = _handler_table_offset;
672 _nmethod_end_offset = _nul_chk_table_offset;
673 _compile_id = compile_id;
674 _comp_level = CompLevel_none;
675 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
676 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
677 _osr_entry_point = NULL;
678 _exception_cache = NULL;
679 _pc_desc_cache.reset_to(NULL);
680 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
681
682 code_buffer->copy_values_to(this);
683 if (ScavengeRootsInCode) {
684 if (detect_scavenge_root_oops()) {
685 CodeCache::add_scavenge_root_nmethod(this);
686 }
687 Universe::heap()->register_nmethod(this);
688 }
689 debug_only(verify_scavenge_root_oops());
690 CodeCache::commit(this);
691 }
692
693 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
694 ttyLocker ttyl; // keep the following output all in one block
695 // This output goes directly to the tty, not the compiler log.
696 // To enable tools to match it up with the compilation activity,
697 // be sure to tag this tty output with the compile ID.
698 if (xtty != NULL) {
699 xtty->begin_head("print_native_nmethod");
700 xtty->method(_method);
701 xtty->stamp();
702 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
703 }
704 // print the header part first
705 print();
706 // then print the requested information
707 if (PrintNativeNMethods) {
708 print_code();
709 if (oop_maps != NULL) {
710 oop_maps->print();
711 }
712 }
713 if (PrintRelocations) {
714 print_relocations();
715 }
716 if (xtty != NULL) {
717 xtty->tail("print_native_nmethod");
718 }
719 }
720 }
721
722 // For dtrace wrappers
723 #ifdef HAVE_DTRACE_H
724 nmethod::nmethod(
725 Method* method,
726 int nmethod_size,
727 CodeOffsets* offsets,
728 CodeBuffer* code_buffer,
729 int frame_size)
730 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
731 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
732 _native_receiver_sp_offset(in_ByteSize(-1)),
733 _native_basic_lock_sp_offset(in_ByteSize(-1))
734 {
735 {
736 debug_only(No_Safepoint_Verifier nsv;)
737 assert_locked_or_safepoint(CodeCache_lock);
738
739 init_defaults();
740 _method = method;
741 _entry_bci = InvocationEntryBci;
742 // We have no exception handler or deopt handler make the
743 // values something that will never match a pc like the nmethod vtable entry
744 _exception_offset = 0;
745 _deoptimize_offset = 0;
746 _deoptimize_mh_offset = 0;
747 _unwind_handler_offset = -1;
748 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
749 _orig_pc_offset = 0;
750 _consts_offset = data_offset();
751 _stub_offset = data_offset();
752 _oops_offset = data_offset();
753 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
754 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
755 _scopes_pcs_offset = _scopes_data_offset;
756 _dependencies_offset = _scopes_pcs_offset;
757 _handler_table_offset = _dependencies_offset;
758 _nul_chk_table_offset = _handler_table_offset;
759 _nmethod_end_offset = _nul_chk_table_offset;
760 _compile_id = 0; // default
761 _comp_level = CompLevel_none;
762 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
763 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
764 _osr_entry_point = NULL;
765 _exception_cache = NULL;
766 _pc_desc_cache.reset_to(NULL);
767 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
768
769 code_buffer->copy_values_to(this);
770 if (ScavengeRootsInCode) {
771 if (detect_scavenge_root_oops()) {
772 CodeCache::add_scavenge_root_nmethod(this);
773 }
774 Universe::heap()->register_nmethod(this);
775 }
776 DEBUG_ONLY(verify_scavenge_root_oops();)
777 CodeCache::commit(this);
778 }
779
780 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
781 ttyLocker ttyl; // keep the following output all in one block
782 // This output goes directly to the tty, not the compiler log.
783 // To enable tools to match it up with the compilation activity,
784 // be sure to tag this tty output with the compile ID.
785 if (xtty != NULL) {
786 xtty->begin_head("print_dtrace_nmethod");
787 xtty->method(_method);
788 xtty->stamp();
789 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
790 }
791 // print the header part first
792 print();
793 // then print the requested information
794 if (PrintNMethods) {
795 print_code();
796 }
797 if (PrintRelocations) {
798 print_relocations();
799 }
800 if (xtty != NULL) {
801 xtty->tail("print_dtrace_nmethod");
802 }
803 }
804 }
805 #endif // def HAVE_DTRACE_H
806
807 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
808 return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
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 // Clear ICStubs of all compiled ICs
1132 void nmethod::clear_ic_stubs() {
1133 assert_locked_or_safepoint(CompiledIC_lock);
1134 RelocIterator iter(this);
1135 while(iter.next()) {
1136 if (iter.type() == relocInfo::virtual_call_type) {
1137 CompiledIC* ic = CompiledIC_at(&iter);
1138 ic->clear_ic_stub();
1139 }
1140 }
1141 }
1142
1143
1144 void nmethod::cleanup_inline_caches() {
1145
1146 assert_locked_or_safepoint(CompiledIC_lock);
1147
1148 // If the method is not entrant or zombie then a JMP is plastered over the
1149 // first few bytes. If an oop in the old code was there, that oop
1150 // should not get GC'd. Skip the first few bytes of oops on
1151 // not-entrant methods.
1152 address low_boundary = verified_entry_point();
1153 if (!is_in_use()) {
1154 low_boundary += NativeJump::instruction_size;
1155 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1156 // This means that the low_boundary is going to be a little too high.
1157 // This shouldn't matter, since oops of non-entrant methods are never used.
1158 // In fact, why are we bothering to look at oops in a non-entrant method??
1159 }
1160
1161 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1162 ResourceMark rm;
1163 RelocIterator iter(this, low_boundary);
1164 while(iter.next()) {
1165 switch(iter.type()) {
1166 case relocInfo::virtual_call_type:
1167 case relocInfo::opt_virtual_call_type: {
1168 CompiledIC *ic = CompiledIC_at(&iter);
1169 // Ok, to lookup references to zombies here
1170 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1171 if( cb != NULL && cb->is_nmethod() ) {
1172 nmethod* nm = (nmethod*)cb;
1173 // Clean inline caches pointing to both zombie and not_entrant methods
1174 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1175 }
1176 break;
1177 }
1178 case relocInfo::static_call_type: {
1179 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1180 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1181 if( cb != NULL && cb->is_nmethod() ) {
1182 nmethod* nm = (nmethod*)cb;
1183 // Clean inline caches pointing to both zombie and not_entrant methods
1184 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1185 }
1186 break;
1187 }
1188 }
1189 }
1190 }
1191
1192 void nmethod::verify_clean_inline_caches() {
1193 assert_locked_or_safepoint(CompiledIC_lock);
1194
1195 // If the method is not entrant or zombie then a JMP is plastered over the
1196 // first few bytes. If an oop in the old code was there, that oop
1197 // should not get GC'd. Skip the first few bytes of oops on
1198 // not-entrant methods.
1199 address low_boundary = verified_entry_point();
1200 if (!is_in_use()) {
1201 low_boundary += NativeJump::instruction_size;
1202 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1203 // This means that the low_boundary is going to be a little too high.
1204 // This shouldn't matter, since oops of non-entrant methods are never used.
1205 // In fact, why are we bothering to look at oops in a non-entrant method??
1206 }
1207
1208 ResourceMark rm;
1209 RelocIterator iter(this, low_boundary);
1210 while(iter.next()) {
1211 switch(iter.type()) {
1212 case relocInfo::virtual_call_type:
1213 case relocInfo::opt_virtual_call_type: {
1214 CompiledIC *ic = CompiledIC_at(&iter);
1215 // Ok, to lookup references to zombies here
1216 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_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(ic->is_clean(), "IC should be clean");
1222 }
1223 }
1224 break;
1225 }
1226 case relocInfo::static_call_type: {
1227 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1228 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1229 if( cb != NULL && cb->is_nmethod() ) {
1230 nmethod* nm = (nmethod*)cb;
1231 // Verify that inline caches pointing to both zombie and not_entrant methods are clean
1232 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1233 assert(csc->is_clean(), "IC should be clean");
1234 }
1235 }
1236 break;
1237 }
1238 }
1239 }
1240 }
1241
1242 int nmethod::verify_icholder_relocations() {
1243 int count = 0;
1244
1245 RelocIterator iter(this);
1246 while(iter.next()) {
1247 if (iter.type() == relocInfo::virtual_call_type) {
1248 if (CompiledIC::is_icholder_call_site(iter.virtual_call_reloc())) {
1249 CompiledIC *ic = CompiledIC_at(&iter);
1250 if (TraceCompiledIC) {
1251 tty->print("noticed icholder " INTPTR_FORMAT " ", p2i(ic->cached_icholder()));
1252 ic->print();
1253 }
1254 assert(ic->cached_icholder() != NULL, "must be non-NULL");
1255 count++;
1256 }
1257 }
1258 }
1259
1260 return count;
1261 }
1262
1263 // This is a private interface with the sweeper.
1264 void nmethod::mark_as_seen_on_stack() {
1265 assert(is_alive(), "Must be an alive method");
1266 // Set the traversal mark to ensure that the sweeper does 2
1267 // cleaning passes before moving to zombie.
1268 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1269 }
1270
1271 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1272 // there are no activations on the stack, not in use by the VM,
1273 // and not in use by the ServiceThread)
1274 bool nmethod::can_not_entrant_be_converted() {
1275 assert(is_not_entrant(), "must be a non-entrant method");
1276
1277 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1278 // count can be greater than the stack traversal count before it hits the
1279 // nmethod for the second time.
1280 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1281 !is_locked_by_vm();
1282 }
1283
1284 void nmethod::inc_decompile_count() {
1285 if (!is_compiled_by_c2()) return;
1286 // Could be gated by ProfileTraps, but do not bother...
1287 Method* m = method();
1288 if (m == NULL) return;
1289 MethodData* mdo = m->method_data();
1290 if (mdo == NULL) return;
1291 // There is a benign race here. See comments in methodData.hpp.
1292 mdo->inc_decompile_count();
1293 }
1294
1295 void nmethod::increase_unloading_clock() {
1296 _global_unloading_clock++;
1297 if (_global_unloading_clock == 0) {
1298 // _nmethods are allocated with _unloading_clock == 0,
1299 // so 0 is never used as a clock value.
1300 _global_unloading_clock = 1;
1301 }
1302 }
1303
1304 void nmethod::set_unloading_clock(unsigned char unloading_clock) {
1305 OrderAccess::release_store((volatile jubyte*)&_unloading_clock, unloading_clock);
1306 }
1307
1308 unsigned char nmethod::unloading_clock() {
1309 return (unsigned char)OrderAccess::load_acquire((volatile jubyte*)&_unloading_clock);
1310 }
1311
1312 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1313
1314 post_compiled_method_unload();
1315
1316 // Since this nmethod is being unloaded, make sure that dependencies
1317 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1318 // indicate that this work is being done during a GC.
1319 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1320 assert(is_alive != NULL, "Should be non-NULL");
1321 // A non-NULL is_alive closure indicates that this is being called during GC.
1322 flush_dependencies(is_alive);
1323
1324 // Break cycle between nmethod & method
1325 if (TraceClassUnloading && WizardMode) {
1326 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1327 " unloadable], Method*(" INTPTR_FORMAT
1328 "), cause(" INTPTR_FORMAT ")",
1329 this, (address)_method, (address)cause);
1330 if (!Universe::heap()->is_gc_active())
1331 cause->klass()->print();
1332 }
1333 // Unlink the osr method, so we do not look this up again
1334 if (is_osr_method()) {
1335 invalidate_osr_method();
1336 }
1337 // If _method is already NULL the Method* is about to be unloaded,
1338 // so we don't have to break the cycle. Note that it is possible to
1339 // have the Method* live here, in case we unload the nmethod because
1340 // it is pointing to some oop (other than the Method*) being unloaded.
1341 if (_method != NULL) {
1342 // OSR methods point to the Method*, but the Method* does not
1343 // point back!
1344 if (_method->code() == this) {
1345 _method->clear_code(); // Break a cycle
1346 }
1347 _method = NULL; // Clear the method of this dead nmethod
1348 }
1349 // Make the class unloaded - i.e., change state and notify sweeper
1350 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1351 if (is_in_use()) {
1352 // Transitioning directly from live to unloaded -- so
1353 // we need to force a cache clean-up; remember this
1354 // for later on.
1355 CodeCache::set_needs_cache_clean(true);
1356 }
1357
1358 // Unregister must be done before the state change
1359 Universe::heap()->unregister_nmethod(this);
1360
1361 _state = unloaded;
1362
1363 // Log the unloading.
1364 log_state_change();
1365
1366 // The Method* is gone at this point
1367 assert(_method == NULL, "Tautology");
1368
1369 set_osr_link(NULL);
1370 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1371 NMethodSweeper::report_state_change(this);
1372 }
1373
1374 void nmethod::invalidate_osr_method() {
1375 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1376 // Remove from list of active nmethods
1377 if (method() != NULL)
1378 method()->method_holder()->remove_osr_nmethod(this);
1379 }
1380
1381 void nmethod::log_state_change() const {
1382 if (LogCompilation) {
1383 if (xtty != NULL) {
1384 ttyLocker ttyl; // keep the following output all in one block
1385 if (_state == unloaded) {
1386 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1387 os::current_thread_id());
1388 } else {
1389 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1390 os::current_thread_id(),
1391 (_state == zombie ? " zombie='1'" : ""));
1392 }
1393 log_identity(xtty);
1394 xtty->stamp();
1395 xtty->end_elem();
1396 }
1397 }
1398 if (PrintCompilation && _state != unloaded) {
1399 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1400 }
1401 }
1402
1403 /**
1404 * Common functionality for both make_not_entrant and make_zombie
1405 */
1406 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1407 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1408 assert(!is_zombie(), "should not already be a zombie");
1409
1410 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1411 nmethodLocker nml(this);
1412 methodHandle the_method(method());
1413 No_Safepoint_Verifier nsv;
1414
1415 // during patching, depending on the nmethod state we must notify the GC that
1416 // code has been unloaded, unregistering it. We cannot do this right while
1417 // holding the Patching_lock because we need to use the CodeCache_lock. This
1418 // would be prone to deadlocks.
1419 // This flag is used to remember whether we need to later lock and unregister.
1420 bool nmethod_needs_unregister = false;
1421
1422 {
1423 // invalidate osr nmethod before acquiring the patching lock since
1424 // they both acquire leaf locks and we don't want a deadlock.
1425 // This logic is equivalent to the logic below for patching the
1426 // verified entry point of regular methods.
1427 if (is_osr_method()) {
1428 // this effectively makes the osr nmethod not entrant
1429 invalidate_osr_method();
1430 }
1431
1432 // Enter critical section. Does not block for safepoint.
1433 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1434
1435 if (_state == state) {
1436 // another thread already performed this transition so nothing
1437 // to do, but return false to indicate this.
1438 return false;
1439 }
1440
1441 // The caller can be calling the method statically or through an inline
1442 // cache call.
1443 if (!is_osr_method() && !is_not_entrant()) {
1444 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1445 SharedRuntime::get_handle_wrong_method_stub());
1446 }
1447
1448 if (is_in_use()) {
1449 // It's a true state change, so mark the method as decompiled.
1450 // Do it only for transition from alive.
1451 inc_decompile_count();
1452 }
1453
1454 // If the state is becoming a zombie, signal to unregister the nmethod with
1455 // the heap.
1456 // This nmethod may have already been unloaded during a full GC.
1457 if ((state == zombie) && !is_unloaded()) {
1458 nmethod_needs_unregister = true;
1459 }
1460
1461 // Must happen before state change. Otherwise we have a race condition in
1462 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1463 // transition its state from 'not_entrant' to 'zombie' without having to wait
1464 // for stack scanning.
1465 if (state == not_entrant) {
1466 mark_as_seen_on_stack();
1467 OrderAccess::storestore();
1468 }
1469
1470 // Change state
1471 _state = state;
1472
1473 // Log the transition once
1474 log_state_change();
1475
1476 // Remove nmethod from method.
1477 // We need to check if both the _code and _from_compiled_code_entry_point
1478 // refer to this nmethod because there is a race in setting these two fields
1479 // in Method* as seen in bugid 4947125.
1480 // If the vep() points to the zombie nmethod, the memory for the nmethod
1481 // could be flushed and the compiler and vtable stubs could still call
1482 // through it.
1483 if (method() != NULL && (method()->code() == this ||
1484 method()->from_compiled_entry() == verified_entry_point())) {
1485 HandleMark hm;
1486 method()->clear_code();
1487 }
1488 } // leave critical region under Patching_lock
1489
1490 // When the nmethod becomes zombie it is no longer alive so the
1491 // dependencies must be flushed. nmethods in the not_entrant
1492 // state will be flushed later when the transition to zombie
1493 // happens or they get unloaded.
1494 if (state == zombie) {
1495 {
1496 // Flushing dependecies must be done before any possible
1497 // safepoint can sneak in, otherwise the oops used by the
1498 // dependency logic could have become stale.
1499 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1500 if (nmethod_needs_unregister) {
1501 Universe::heap()->unregister_nmethod(this);
1502 }
1503 flush_dependencies(NULL);
1504 }
1505
1506 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1507 // event and it hasn't already been reported for this nmethod then
1508 // report it now. The event may have been reported earilier if the GC
1509 // marked it for unloading). JvmtiDeferredEventQueue support means
1510 // we no longer go to a safepoint here.
1511 post_compiled_method_unload();
1512
1513 #ifdef ASSERT
1514 // It's no longer safe to access the oops section since zombie
1515 // nmethods aren't scanned for GC.
1516 _oops_are_stale = true;
1517 #endif
1518 // the Method may be reclaimed by class unloading now that the
1519 // nmethod is in zombie state
1520 set_method(NULL);
1521 } else {
1522 assert(state == not_entrant, "other cases may need to be handled differently");
1523 }
1524
1525 if (TraceCreateZombies) {
1526 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1527 }
1528
1529 NMethodSweeper::report_state_change(this);
1530 return true;
1531 }
1532
1533 void nmethod::flush() {
1534 // Note that there are no valid oops in the nmethod anymore.
1535 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1536 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1537
1538 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1539 assert_locked_or_safepoint(CodeCache_lock);
1540
1541 // completely deallocate this method
1542 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1543 if (PrintMethodFlushing) {
1544 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1545 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(_comp_level))/1024);
1546 }
1547
1548 // We need to deallocate any ExceptionCache data.
1549 // Note that we do not need to grab the nmethod lock for this, it
1550 // better be thread safe if we're disposing of it!
1551 ExceptionCache* ec = exception_cache();
1552 set_exception_cache(NULL);
1553 while(ec != NULL) {
1554 ExceptionCache* next = ec->next();
1555 delete ec;
1556 ec = next;
1557 }
1558
1559 if (on_scavenge_root_list()) {
1560 CodeCache::drop_scavenge_root_nmethod(this);
1561 }
1562
1563 #ifdef SHARK
1564 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1565 #endif // SHARK
1566
1567 ((CodeBlob*)(this))->flush();
1568
1569 CodeCache::free(this);
1570 }
1571
1572 //
1573 // Notify all classes this nmethod is dependent on that it is no
1574 // longer dependent. This should only be called in two situations.
1575 // First, when a nmethod transitions to a zombie all dependents need
1576 // to be clear. Since zombification happens at a safepoint there's no
1577 // synchronization issues. The second place is a little more tricky.
1578 // During phase 1 of mark sweep class unloading may happen and as a
1579 // result some nmethods may get unloaded. In this case the flushing
1580 // of dependencies must happen during phase 1 since after GC any
1581 // dependencies in the unloaded nmethod won't be updated, so
1582 // traversing the dependency information in unsafe. In that case this
1583 // function is called with a non-NULL argument and this function only
1584 // notifies instanceKlasses that are reachable
1585
1586 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1587 assert_locked_or_safepoint(CodeCache_lock);
1588 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1589 "is_alive is non-NULL if and only if we are called during GC");
1590 if (!has_flushed_dependencies()) {
1591 set_has_flushed_dependencies();
1592 for (Dependencies::DepStream deps(this); deps.next(); ) {
1593 Klass* klass = deps.context_type();
1594 if (klass == NULL) continue; // ignore things like evol_method
1595
1596 // During GC the is_alive closure is non-NULL, and is used to
1597 // determine liveness of dependees that need to be updated.
1598 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1599 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1600 }
1601 }
1602 }
1603 }
1604
1605
1606 // If this oop is not live, the nmethod can be unloaded.
1607 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1608 assert(root != NULL, "just checking");
1609 oop obj = *root;
1610 if (obj == NULL || is_alive->do_object_b(obj)) {
1611 return false;
1612 }
1613
1614 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1615 // simply because one of its constant oops has gone dead.
1616 // No actual classes need to be unloaded in order for this to occur.
1617 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1618 make_unloaded(is_alive, obj);
1619 return true;
1620 }
1621
1622 // ------------------------------------------------------------------
1623 // post_compiled_method_load_event
1624 // new method for install_code() path
1625 // Transfer information from compilation to jvmti
1626 void nmethod::post_compiled_method_load_event() {
1627
1628 Method* moop = method();
1629 HOTSPOT_COMPILED_METHOD_LOAD(
1630 (char *) moop->klass_name()->bytes(),
1631 moop->klass_name()->utf8_length(),
1632 (char *) moop->name()->bytes(),
1633 moop->name()->utf8_length(),
1634 (char *) moop->signature()->bytes(),
1635 moop->signature()->utf8_length(),
1636 insts_begin(), insts_size());
1637
1638 if (JvmtiExport::should_post_compiled_method_load() ||
1639 JvmtiExport::should_post_compiled_method_unload()) {
1640 get_and_cache_jmethod_id();
1641 }
1642
1643 if (JvmtiExport::should_post_compiled_method_load()) {
1644 // Let the Service thread (which is a real Java thread) post the event
1645 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1646 JvmtiDeferredEventQueue::enqueue(
1647 JvmtiDeferredEvent::compiled_method_load_event(this));
1648 }
1649 }
1650
1651 jmethodID nmethod::get_and_cache_jmethod_id() {
1652 if (_jmethod_id == NULL) {
1653 // Cache the jmethod_id since it can no longer be looked up once the
1654 // method itself has been marked for unloading.
1655 _jmethod_id = method()->jmethod_id();
1656 }
1657 return _jmethod_id;
1658 }
1659
1660 void nmethod::post_compiled_method_unload() {
1661 if (unload_reported()) {
1662 // During unloading we transition to unloaded and then to zombie
1663 // and the unloading is reported during the first transition.
1664 return;
1665 }
1666
1667 assert(_method != NULL && !is_unloaded(), "just checking");
1668 DTRACE_METHOD_UNLOAD_PROBE(method());
1669
1670 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1671 // post the event. Sometime later this nmethod will be made a zombie
1672 // by the sweeper but the Method* will not be valid at that point.
1673 // If the _jmethod_id is null then no load event was ever requested
1674 // so don't bother posting the unload. The main reason for this is
1675 // that the jmethodID is a weak reference to the Method* so if
1676 // it's being unloaded there's no way to look it up since the weak
1677 // ref will have been cleared.
1678 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1679 assert(!unload_reported(), "already unloaded");
1680 JvmtiDeferredEvent event =
1681 JvmtiDeferredEvent::compiled_method_unload_event(this,
1682 _jmethod_id, insts_begin());
1683 if (SafepointSynchronize::is_at_safepoint()) {
1684 // Don't want to take the queueing lock. Add it as pending and
1685 // it will get enqueued later.
1686 JvmtiDeferredEventQueue::add_pending_event(event);
1687 } else {
1688 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1689 JvmtiDeferredEventQueue::enqueue(event);
1690 }
1691 }
1692
1693 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1694 // any time. As the nmethod is being unloaded now we mark it has
1695 // having the unload event reported - this will ensure that we don't
1696 // attempt to report the event in the unlikely scenario where the
1697 // event is enabled at the time the nmethod is made a zombie.
1698 set_unload_reported();
1699 }
1700
1701 void static clean_ic_if_metadata_is_dead(CompiledIC *ic, BoolObjectClosure *is_alive, bool mark_on_stack) {
1702 if (ic->is_icholder_call()) {
1703 // The only exception is compiledICHolder oops which may
1704 // yet be marked below. (We check this further below).
1705 CompiledICHolder* cichk_oop = ic->cached_icholder();
1706
1707 if (mark_on_stack) {
1708 Metadata::mark_on_stack(cichk_oop->holder_method());
1709 Metadata::mark_on_stack(cichk_oop->holder_klass());
1710 }
1711
1712 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1713 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1714 return;
1715 }
1716 } else {
1717 Metadata* ic_oop = ic->cached_metadata();
1718 if (ic_oop != NULL) {
1719 if (mark_on_stack) {
1720 Metadata::mark_on_stack(ic_oop);
1721 }
1722
1723 if (ic_oop->is_klass()) {
1724 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1725 return;
1726 }
1727 } else if (ic_oop->is_method()) {
1728 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1729 return;
1730 }
1731 } else {
1732 ShouldNotReachHere();
1733 }
1734 }
1735 }
1736
1737 ic->set_to_clean();
1738 }
1739
1740 // This is called at the end of the strong tracing/marking phase of a
1741 // GC to unload an nmethod if it contains otherwise unreachable
1742 // oops.
1743
1744 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1745 // Make sure the oop's ready to receive visitors
1746 assert(!is_zombie() && !is_unloaded(),
1747 "should not call follow on zombie or unloaded nmethod");
1748
1749 // If the method is not entrant then a JMP is plastered over the
1750 // first few bytes. If an oop in the old code was there, that oop
1751 // should not get GC'd. Skip the first few bytes of oops on
1752 // not-entrant methods.
1753 address low_boundary = verified_entry_point();
1754 if (is_not_entrant()) {
1755 low_boundary += NativeJump::instruction_size;
1756 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1757 // (See comment above.)
1758 }
1759
1760 // The RedefineClasses() API can cause the class unloading invariant
1761 // to no longer be true. See jvmtiExport.hpp for details.
1762 // Also, leave a debugging breadcrumb in local flag.
1763 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1764 if (a_class_was_redefined) {
1765 // This set of the unloading_occurred flag is done before the
1766 // call to post_compiled_method_unload() so that the unloading
1767 // of this nmethod is reported.
1768 unloading_occurred = true;
1769 }
1770
1771 // Exception cache
1772 clean_exception_cache(is_alive);
1773
1774 // If class unloading occurred we first iterate over all inline caches and
1775 // clear ICs where the cached oop is referring to an unloaded klass or method.
1776 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1777 // iteration below.
1778 if (unloading_occurred) {
1779 RelocIterator iter(this, low_boundary);
1780 while(iter.next()) {
1781 if (iter.type() == relocInfo::virtual_call_type) {
1782 CompiledIC *ic = CompiledIC_at(&iter);
1783 clean_ic_if_metadata_is_dead(ic, is_alive, false);
1784 }
1785 }
1786 }
1787
1788 // Compiled code
1789 {
1790 RelocIterator iter(this, low_boundary);
1791 while (iter.next()) {
1792 if (iter.type() == relocInfo::oop_type) {
1793 oop_Relocation* r = iter.oop_reloc();
1794 // In this loop, we must only traverse those oops directly embedded in
1795 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1796 assert(1 == (r->oop_is_immediate()) +
1797 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1798 "oop must be found in exactly one place");
1799 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1800 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1801 return;
1802 }
1803 }
1804 }
1805 }
1806 }
1807
1808
1809 // Scopes
1810 for (oop* p = oops_begin(); p < oops_end(); p++) {
1811 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1812 if (can_unload(is_alive, p, unloading_occurred)) {
1813 return;
1814 }
1815 }
1816
1817 // Ensure that all metadata is still alive
1818 verify_metadata_loaders(low_boundary, is_alive);
1819 }
1820
1821 template <class CompiledICorStaticCall>
1822 static bool clean_if_nmethod_is_unloaded(CompiledICorStaticCall *ic, address addr, BoolObjectClosure *is_alive, nmethod* from) {
1823 // Ok, to lookup references to zombies here
1824 CodeBlob *cb = CodeCache::find_blob_unsafe(addr);
1825 if (cb != NULL && cb->is_nmethod()) {
1826 nmethod* nm = (nmethod*)cb;
1827
1828 if (nm->unloading_clock() != nmethod::global_unloading_clock()) {
1829 // The nmethod has not been processed yet.
1830 return true;
1831 }
1832
1833 // Clean inline caches pointing to both zombie and not_entrant methods
1834 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1835 ic->set_to_clean();
1836 assert(ic->is_clean(), err_msg("nmethod " PTR_FORMAT "not clean %s", from, from->method()->name_and_sig_as_C_string()));
1837 }
1838 }
1839
1840 return false;
1841 }
1842
1843 static bool clean_if_nmethod_is_unloaded(CompiledIC *ic, BoolObjectClosure *is_alive, nmethod* from) {
1844 return clean_if_nmethod_is_unloaded(ic, ic->ic_destination(), is_alive, from);
1845 }
1846
1847 static bool clean_if_nmethod_is_unloaded(CompiledStaticCall *csc, BoolObjectClosure *is_alive, nmethod* from) {
1848 return clean_if_nmethod_is_unloaded(csc, csc->destination(), is_alive, from);
1849 }
1850
1851 bool nmethod::unload_if_dead_at(RelocIterator* iter_at_oop, BoolObjectClosure *is_alive, bool unloading_occurred) {
1852 assert(iter_at_oop->type() == relocInfo::oop_type, "Wrong relocation type");
1853
1854 oop_Relocation* r = iter_at_oop->oop_reloc();
1855 // Traverse those oops directly embedded in the code.
1856 // Other oops (oop_index>0) are seen as part of scopes_oops.
1857 assert(1 == (r->oop_is_immediate()) +
1858 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1859 "oop must be found in exactly one place");
1860 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1861 // Unload this nmethod if the oop is dead.
1862 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1863 return true;;
1864 }
1865 }
1866
1867 return false;
1868 }
1869
1870 void nmethod::mark_metadata_on_stack_at(RelocIterator* iter_at_metadata) {
1871 assert(iter_at_metadata->type() == relocInfo::metadata_type, "Wrong relocation type");
1872
1873 metadata_Relocation* r = iter_at_metadata->metadata_reloc();
1874 // In this metadata, we must only follow those metadatas directly embedded in
1875 // the code. Other metadatas (oop_index>0) are seen as part of
1876 // the metadata section below.
1877 assert(1 == (r->metadata_is_immediate()) +
1878 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1879 "metadata must be found in exactly one place");
1880 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1881 Metadata* md = r->metadata_value();
1882 if (md != _method) Metadata::mark_on_stack(md);
1883 }
1884 }
1885
1886 void nmethod::mark_metadata_on_stack_non_relocs() {
1887 // Visit the metadata section
1888 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1889 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
1890 Metadata* md = *p;
1891 Metadata::mark_on_stack(md);
1892 }
1893
1894 // Visit metadata not embedded in the other places.
1895 if (_method != NULL) Metadata::mark_on_stack(_method);
1896 }
1897
1898 bool nmethod::do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred) {
1899 ResourceMark rm;
1900
1901 // Make sure the oop's ready to receive visitors
1902 assert(!is_zombie() && !is_unloaded(),
1903 "should not call follow on zombie or unloaded nmethod");
1904
1905 // If the method is not entrant then a JMP is plastered over the
1906 // first few bytes. If an oop in the old code was there, that oop
1907 // should not get GC'd. Skip the first few bytes of oops on
1908 // not-entrant methods.
1909 address low_boundary = verified_entry_point();
1910 if (is_not_entrant()) {
1911 low_boundary += NativeJump::instruction_size;
1912 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1913 // (See comment above.)
1914 }
1915
1916 // The RedefineClasses() API can cause the class unloading invariant
1917 // to no longer be true. See jvmtiExport.hpp for details.
1918 // Also, leave a debugging breadcrumb in local flag.
1919 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1920 if (a_class_was_redefined) {
1921 // This set of the unloading_occurred flag is done before the
1922 // call to post_compiled_method_unload() so that the unloading
1923 // of this nmethod is reported.
1924 unloading_occurred = true;
1925 }
1926
1927 // When class redefinition is used all metadata in the CodeCache has to be recorded,
1928 // so that unused "previous versions" can be purged. Since walking the CodeCache can
1929 // be expensive, the "mark on stack" is piggy-backed on this parallel unloading code.
1930 bool mark_metadata_on_stack = a_class_was_redefined;
1931
1932 // Exception cache
1933 clean_exception_cache(is_alive);
1934
1935 bool is_unloaded = false;
1936 bool postponed = false;
1937
1938 RelocIterator iter(this, low_boundary);
1939 while(iter.next()) {
1940
1941 switch (iter.type()) {
1942
1943 case relocInfo::virtual_call_type:
1944 if (unloading_occurred) {
1945 // If class unloading occurred we first iterate over all inline caches and
1946 // clear ICs where the cached oop is referring to an unloaded klass or method.
1947 clean_ic_if_metadata_is_dead(CompiledIC_at(&iter), is_alive, mark_metadata_on_stack);
1948 }
1949
1950 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1951 break;
1952
1953 case relocInfo::opt_virtual_call_type:
1954 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1955 break;
1956
1957 case relocInfo::static_call_type:
1958 postponed |= clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
1959 break;
1960
1961 case relocInfo::oop_type:
1962 if (!is_unloaded) {
1963 is_unloaded = unload_if_dead_at(&iter, is_alive, unloading_occurred);
1964 }
1965 break;
1966
1967 case relocInfo::metadata_type:
1968 if (mark_metadata_on_stack) {
1969 mark_metadata_on_stack_at(&iter);
1970 }
1971 }
1972 }
1973
1974 if (mark_metadata_on_stack) {
1975 mark_metadata_on_stack_non_relocs();
1976 }
1977
1978 if (is_unloaded) {
1979 return postponed;
1980 }
1981
1982 // Scopes
1983 for (oop* p = oops_begin(); p < oops_end(); p++) {
1984 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1985 if (can_unload(is_alive, p, unloading_occurred)) {
1986 is_unloaded = true;
1987 break;
1988 }
1989 }
1990
1991 if (is_unloaded) {
1992 return postponed;
1993 }
1994
1995 // Ensure that all metadata is still alive
1996 verify_metadata_loaders(low_boundary, is_alive);
1997
1998 return postponed;
1999 }
2000
2001 void nmethod::do_unloading_parallel_postponed(BoolObjectClosure* is_alive, bool unloading_occurred) {
2002 ResourceMark rm;
2003
2004 // Make sure the oop's ready to receive visitors
2005 assert(!is_zombie(),
2006 "should not call follow on zombie nmethod");
2007
2008 // If the method is not entrant then a JMP is plastered over the
2009 // first few bytes. If an oop in the old code was there, that oop
2010 // should not get GC'd. Skip the first few bytes of oops on
2011 // not-entrant methods.
2012 address low_boundary = verified_entry_point();
2013 if (is_not_entrant()) {
2014 low_boundary += NativeJump::instruction_size;
2015 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
2016 // (See comment above.)
2017 }
2018
2019 RelocIterator iter(this, low_boundary);
2020 while(iter.next()) {
2021
2022 switch (iter.type()) {
2023
2024 case relocInfo::virtual_call_type:
2025 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
2026 break;
2027
2028 case relocInfo::opt_virtual_call_type:
2029 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
2030 break;
2031
2032 case relocInfo::static_call_type:
2033 clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
2034 break;
2035 }
2036 }
2037 }
2038
2039 #ifdef ASSERT
2040
2041 class CheckClass : AllStatic {
2042 static BoolObjectClosure* _is_alive;
2043
2044 // Check class_loader is alive for this bit of metadata.
2045 static void check_class(Metadata* md) {
2046 Klass* klass = NULL;
2047 if (md->is_klass()) {
2048 klass = ((Klass*)md);
2049 } else if (md->is_method()) {
2050 klass = ((Method*)md)->method_holder();
2051 } else if (md->is_methodData()) {
2052 klass = ((MethodData*)md)->method()->method_holder();
2053 } else {
2054 md->print();
2055 ShouldNotReachHere();
2056 }
2057 assert(klass->is_loader_alive(_is_alive), "must be alive");
2058 }
2059 public:
2060 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
2061 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
2062 _is_alive = is_alive;
2063 nm->metadata_do(check_class);
2064 }
2065 };
2066
2067 // This is called during a safepoint so can use static data
2068 BoolObjectClosure* CheckClass::_is_alive = NULL;
2069 #endif // ASSERT
2070
2071
2072 // Processing of oop references should have been sufficient to keep
2073 // all strong references alive. Any weak references should have been
2074 // cleared as well. Visit all the metadata and ensure that it's
2075 // really alive.
2076 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
2077 #ifdef ASSERT
2078 RelocIterator iter(this, low_boundary);
2079 while (iter.next()) {
2080 // static_stub_Relocations may have dangling references to
2081 // Method*s so trim them out here. Otherwise it looks like
2082 // compiled code is maintaining a link to dead metadata.
2083 address static_call_addr = NULL;
2084 if (iter.type() == relocInfo::opt_virtual_call_type) {
2085 CompiledIC* cic = CompiledIC_at(&iter);
2086 if (!cic->is_call_to_interpreted()) {
2087 static_call_addr = iter.addr();
2088 }
2089 } else if (iter.type() == relocInfo::static_call_type) {
2090 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
2091 if (!csc->is_call_to_interpreted()) {
2092 static_call_addr = iter.addr();
2093 }
2094 }
2095 if (static_call_addr != NULL) {
2096 RelocIterator sciter(this, low_boundary);
2097 while (sciter.next()) {
2098 if (sciter.type() == relocInfo::static_stub_type &&
2099 sciter.static_stub_reloc()->static_call() == static_call_addr) {
2100 sciter.static_stub_reloc()->clear_inline_cache();
2101 }
2102 }
2103 }
2104 }
2105 // Check that the metadata embedded in the nmethod is alive
2106 CheckClass::do_check_class(is_alive, this);
2107 #endif
2108 }
2109
2110
2111 // Iterate over metadata calling this function. Used by RedefineClasses
2112 void nmethod::metadata_do(void f(Metadata*)) {
2113 address low_boundary = verified_entry_point();
2114 if (is_not_entrant()) {
2115 low_boundary += NativeJump::instruction_size;
2116 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
2117 // (See comment above.)
2118 }
2119 {
2120 // Visit all immediate references that are embedded in the instruction stream.
2121 RelocIterator iter(this, low_boundary);
2122 while (iter.next()) {
2123 if (iter.type() == relocInfo::metadata_type ) {
2124 metadata_Relocation* r = iter.metadata_reloc();
2125 // In this metadata, we must only follow those metadatas directly embedded in
2126 // the code. Other metadatas (oop_index>0) are seen as part of
2127 // the metadata section below.
2128 assert(1 == (r->metadata_is_immediate()) +
2129 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
2130 "metadata must be found in exactly one place");
2131 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
2132 Metadata* md = r->metadata_value();
2133 if (md != _method) f(md);
2134 }
2135 } else if (iter.type() == relocInfo::virtual_call_type) {
2136 // Check compiledIC holders associated with this nmethod
2137 CompiledIC *ic = CompiledIC_at(&iter);
2138 if (ic->is_icholder_call()) {
2139 CompiledICHolder* cichk = ic->cached_icholder();
2140 f(cichk->holder_method());
2141 f(cichk->holder_klass());
2142 } else {
2143 Metadata* ic_oop = ic->cached_metadata();
2144 if (ic_oop != NULL) {
2145 f(ic_oop);
2146 }
2147 }
2148 }
2149 }
2150 }
2151
2152 // Visit the metadata section
2153 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
2154 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
2155 Metadata* md = *p;
2156 f(md);
2157 }
2158
2159 // Visit metadata not embedded in the other places.
2160 if (_method != NULL) f(_method);
2161 }
2162
2163 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
2164 // make sure the oops ready to receive visitors
2165 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
2166 assert(!is_unloaded(), "should not call follow on unloaded nmethod");
2167
2168 // If the method is not entrant or zombie then a JMP is plastered over the
2169 // first few bytes. If an oop in the old code was there, that oop
2170 // should not get GC'd. Skip the first few bytes of oops on
2171 // not-entrant methods.
2172 address low_boundary = verified_entry_point();
2173 if (is_not_entrant()) {
2174 low_boundary += NativeJump::instruction_size;
2175 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
2176 // (See comment above.)
2177 }
2178
2179 RelocIterator iter(this, low_boundary);
2180
2181 while (iter.next()) {
2182 if (iter.type() == relocInfo::oop_type ) {
2183 oop_Relocation* r = iter.oop_reloc();
2184 // In this loop, we must only follow those oops directly embedded in
2185 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
2186 assert(1 == (r->oop_is_immediate()) +
2187 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
2188 "oop must be found in exactly one place");
2189 if (r->oop_is_immediate() && r->oop_value() != NULL) {
2190 f->do_oop(r->oop_addr());
2191 }
2192 }
2193 }
2194
2195 // Scopes
2196 // This includes oop constants not inlined in the code stream.
2197 for (oop* p = oops_begin(); p < oops_end(); p++) {
2198 if (*p == Universe::non_oop_word()) continue; // skip non-oops
2199 f->do_oop(p);
2200 }
2201 }
2202
2203 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
2204
2205 nmethod* volatile nmethod::_oops_do_mark_nmethods;
2206
2207 // An nmethod is "marked" if its _mark_link is set non-null.
2208 // Even if it is the end of the linked list, it will have a non-null link value,
2209 // as long as it is on the list.
2210 // This code must be MP safe, because it is used from parallel GC passes.
2211 bool nmethod::test_set_oops_do_mark() {
2212 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
2213 nmethod* observed_mark_link = _oops_do_mark_link;
2214 if (observed_mark_link == NULL) {
2215 // Claim this nmethod for this thread to mark.
2216 observed_mark_link = (nmethod*)
2217 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
2218 if (observed_mark_link == NULL) {
2219
2220 // Atomically append this nmethod (now claimed) to the head of the list:
2221 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
2222 for (;;) {
2223 nmethod* required_mark_nmethods = observed_mark_nmethods;
2224 _oops_do_mark_link = required_mark_nmethods;
2225 observed_mark_nmethods = (nmethod*)
2226 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
2227 if (observed_mark_nmethods == required_mark_nmethods)
2228 break;
2229 }
2230 // Mark was clear when we first saw this guy.
2231 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
2232 return false;
2233 }
2234 }
2235 // On fall through, another racing thread marked this nmethod before we did.
2236 return true;
2237 }
2238
2239 void nmethod::oops_do_marking_prologue() {
2240 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
2241 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
2242 // We use cmpxchg_ptr instead of regular assignment here because the user
2243 // may fork a bunch of threads, and we need them all to see the same state.
2244 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
2245 guarantee(observed == NULL, "no races in this sequential code");
2246 }
2247
2248 void nmethod::oops_do_marking_epilogue() {
2249 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
2250 nmethod* cur = _oops_do_mark_nmethods;
2251 while (cur != NMETHOD_SENTINEL) {
2252 assert(cur != NULL, "not NULL-terminated");
2253 nmethod* next = cur->_oops_do_mark_link;
2254 cur->_oops_do_mark_link = NULL;
2255 cur->verify_oop_relocations();
2256 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
2257 cur = next;
2258 }
2259 void* required = _oops_do_mark_nmethods;
2260 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
2261 guarantee(observed == required, "no races in this sequential code");
2262 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
2263 }
2264
2265 class DetectScavengeRoot: public OopClosure {
2266 bool _detected_scavenge_root;
2267 public:
2268 DetectScavengeRoot() : _detected_scavenge_root(false)
2269 { NOT_PRODUCT(_print_nm = NULL); }
2270 bool detected_scavenge_root() { return _detected_scavenge_root; }
2271 virtual void do_oop(oop* p) {
2272 if ((*p) != NULL && (*p)->is_scavengable()) {
2273 NOT_PRODUCT(maybe_print(p));
2274 _detected_scavenge_root = true;
2275 }
2276 }
2277 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2278
2279 #ifndef PRODUCT
2280 nmethod* _print_nm;
2281 void maybe_print(oop* p) {
2282 if (_print_nm == NULL) return;
2283 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
2284 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
2285 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
2286 (void *)(*p), (intptr_t)p);
2287 (*p)->print();
2288 }
2289 #endif //PRODUCT
2290 };
2291
2292 bool nmethod::detect_scavenge_root_oops() {
2293 DetectScavengeRoot detect_scavenge_root;
2294 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
2295 oops_do(&detect_scavenge_root);
2296 return detect_scavenge_root.detected_scavenge_root();
2297 }
2298
2299 // Method that knows how to preserve outgoing arguments at call. This method must be
2300 // called with a frame corresponding to a Java invoke
2301 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
2302 #ifndef SHARK
2303 if (!method()->is_native()) {
2304 SimpleScopeDesc ssd(this, fr.pc());
2305 Bytecode_invoke call(ssd.method(), ssd.bci());
2306 bool has_receiver = call.has_receiver();
2307 bool has_appendix = call.has_appendix();
2308 Symbol* signature = call.signature();
2309 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
2310 }
2311 #endif // !SHARK
2312 }
2313
2314
2315 oop nmethod::embeddedOop_at(u_char* p) {
2316 RelocIterator iter(this, p, p + 1);
2317 while (iter.next())
2318 if (iter.type() == relocInfo::oop_type) {
2319 return iter.oop_reloc()->oop_value();
2320 }
2321 return NULL;
2322 }
2323
2324
2325 inline bool includes(void* p, void* from, void* to) {
2326 return from <= p && p < to;
2327 }
2328
2329
2330 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2331 assert(count >= 2, "must be sentinel values, at least");
2332
2333 #ifdef ASSERT
2334 // must be sorted and unique; we do a binary search in find_pc_desc()
2335 int prev_offset = pcs[0].pc_offset();
2336 assert(prev_offset == PcDesc::lower_offset_limit,
2337 "must start with a sentinel");
2338 for (int i = 1; i < count; i++) {
2339 int this_offset = pcs[i].pc_offset();
2340 assert(this_offset > prev_offset, "offsets must be sorted");
2341 prev_offset = this_offset;
2342 }
2343 assert(prev_offset == PcDesc::upper_offset_limit,
2344 "must end with a sentinel");
2345 #endif //ASSERT
2346
2347 // Search for MethodHandle invokes and tag the nmethod.
2348 for (int i = 0; i < count; i++) {
2349 if (pcs[i].is_method_handle_invoke()) {
2350 set_has_method_handle_invokes(true);
2351 break;
2352 }
2353 }
2354 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2355
2356 int size = count * sizeof(PcDesc);
2357 assert(scopes_pcs_size() >= size, "oob");
2358 memcpy(scopes_pcs_begin(), pcs, size);
2359
2360 // Adjust the final sentinel downward.
2361 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2362 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2363 last_pc->set_pc_offset(content_size() + 1);
2364 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2365 // Fill any rounding gaps with copies of the last record.
2366 last_pc[1] = last_pc[0];
2367 }
2368 // The following assert could fail if sizeof(PcDesc) is not
2369 // an integral multiple of oopSize (the rounding term).
2370 // If it fails, change the logic to always allocate a multiple
2371 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2372 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2373 }
2374
2375 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2376 assert(scopes_data_size() >= size, "oob");
2377 memcpy(scopes_data_begin(), buffer, size);
2378 }
2379
2380
2381 #ifdef ASSERT
2382 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2383 PcDesc* lower = nm->scopes_pcs_begin();
2384 PcDesc* upper = nm->scopes_pcs_end();
2385 lower += 1; // exclude initial sentinel
2386 PcDesc* res = NULL;
2387 for (PcDesc* p = lower; p < upper; p++) {
2388 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2389 if (match_desc(p, pc_offset, approximate)) {
2390 if (res == NULL)
2391 res = p;
2392 else
2393 res = (PcDesc*) badAddress;
2394 }
2395 }
2396 return res;
2397 }
2398 #endif
2399
2400
2401 // Finds a PcDesc with real-pc equal to "pc"
2402 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2403 address base_address = code_begin();
2404 if ((pc < base_address) ||
2405 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2406 return NULL; // PC is wildly out of range
2407 }
2408 int pc_offset = (int) (pc - base_address);
2409
2410 // Check the PcDesc cache if it contains the desired PcDesc
2411 // (This as an almost 100% hit rate.)
2412 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2413 if (res != NULL) {
2414 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2415 return res;
2416 }
2417
2418 // Fallback algorithm: quasi-linear search for the PcDesc
2419 // Find the last pc_offset less than the given offset.
2420 // The successor must be the required match, if there is a match at all.
2421 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2422 PcDesc* lower = scopes_pcs_begin();
2423 PcDesc* upper = scopes_pcs_end();
2424 upper -= 1; // exclude final sentinel
2425 if (lower >= upper) return NULL; // native method; no PcDescs at all
2426
2427 #define assert_LU_OK \
2428 /* invariant on lower..upper during the following search: */ \
2429 assert(lower->pc_offset() < pc_offset, "sanity"); \
2430 assert(upper->pc_offset() >= pc_offset, "sanity")
2431 assert_LU_OK;
2432
2433 // Use the last successful return as a split point.
2434 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2435 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2436 if (mid->pc_offset() < pc_offset) {
2437 lower = mid;
2438 } else {
2439 upper = mid;
2440 }
2441
2442 // Take giant steps at first (4096, then 256, then 16, then 1)
2443 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2444 const int RADIX = (1 << LOG2_RADIX);
2445 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2446 while ((mid = lower + step) < upper) {
2447 assert_LU_OK;
2448 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2449 if (mid->pc_offset() < pc_offset) {
2450 lower = mid;
2451 } else {
2452 upper = mid;
2453 break;
2454 }
2455 }
2456 assert_LU_OK;
2457 }
2458
2459 // Sneak up on the value with a linear search of length ~16.
2460 while (true) {
2461 assert_LU_OK;
2462 mid = lower + 1;
2463 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2464 if (mid->pc_offset() < pc_offset) {
2465 lower = mid;
2466 } else {
2467 upper = mid;
2468 break;
2469 }
2470 }
2471 #undef assert_LU_OK
2472
2473 if (match_desc(upper, pc_offset, approximate)) {
2474 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2475 _pc_desc_cache.add_pc_desc(upper);
2476 return upper;
2477 } else {
2478 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2479 return NULL;
2480 }
2481 }
2482
2483
2484 void nmethod::check_all_dependencies(DepChange& changes) {
2485 // Checked dependencies are allocated into this ResourceMark
2486 ResourceMark rm;
2487
2488 // Turn off dependency tracing while actually testing dependencies.
2489 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
2490
2491 typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
2492 &DependencySignature::equals, 11027> DepTable;
2493
2494 DepTable* table = new DepTable();
2495
2496 // Iterate over live nmethods and check dependencies of all nmethods that are not
2497 // marked for deoptimization. A particular dependency is only checked once.
2498 NMethodIterator iter;
2499 while(iter.next()) {
2500 nmethod* nm = iter.method();
2501 // Only notify for live nmethods
2502 if (nm->is_alive() && !nm->is_marked_for_deoptimization()) {
2503 for (Dependencies::DepStream deps(nm); deps.next(); ) {
2504 // Construct abstraction of a dependency.
2505 DependencySignature* current_sig = new DependencySignature(deps);
2506
2507 // Determine if dependency is already checked. table->put(...) returns
2508 // 'true' if the dependency is added (i.e., was not in the hashtable).
2509 if (table->put(*current_sig, 1)) {
2510 if (deps.check_dependency() != NULL) {
2511 // Dependency checking failed. Print out information about the failed
2512 // dependency and finally fail with an assert. We can fail here, since
2513 // dependency checking is never done in a product build.
2514 changes.print();
2515 nm->print();
2516 nm->print_dependencies();
2517 assert(false, "Should have been marked for deoptimization");
2518 }
2519 }
2520 }
2521 }
2522 }
2523 }
2524
2525 bool nmethod::check_dependency_on(DepChange& changes) {
2526 // What has happened:
2527 // 1) a new class dependee has been added
2528 // 2) dependee and all its super classes have been marked
2529 bool found_check = false; // set true if we are upset
2530 for (Dependencies::DepStream deps(this); deps.next(); ) {
2531 // Evaluate only relevant dependencies.
2532 if (deps.spot_check_dependency_at(changes) != NULL) {
2533 found_check = true;
2534 NOT_DEBUG(break);
2535 }
2536 }
2537 return found_check;
2538 }
2539
2540 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2541 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2542 Array<Method*>* dependee_methods = dependee_ik->methods();
2543 for (Dependencies::DepStream deps(this); deps.next(); ) {
2544 if (deps.type() == Dependencies::evol_method) {
2545 Method* method = deps.method_argument(0);
2546 for (int j = 0; j < dependee_methods->length(); j++) {
2547 if (dependee_methods->at(j) == method) {
2548 // RC_TRACE macro has an embedded ResourceMark
2549 RC_TRACE(0x01000000,
2550 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2551 _method->method_holder()->external_name(),
2552 _method->name()->as_C_string(),
2553 _method->signature()->as_C_string(), compile_id(),
2554 method->method_holder()->external_name(),
2555 method->name()->as_C_string(),
2556 method->signature()->as_C_string()));
2557 if (TraceDependencies || LogCompilation)
2558 deps.log_dependency(dependee);
2559 return true;
2560 }
2561 }
2562 }
2563 }
2564 return false;
2565 }
2566
2567 // Called from mark_for_deoptimization, when dependee is invalidated.
2568 bool nmethod::is_dependent_on_method(Method* dependee) {
2569 for (Dependencies::DepStream deps(this); deps.next(); ) {
2570 if (deps.type() != Dependencies::evol_method)
2571 continue;
2572 Method* method = deps.method_argument(0);
2573 if (method == dependee) return true;
2574 }
2575 return false;
2576 }
2577
2578
2579 bool nmethod::is_patchable_at(address instr_addr) {
2580 assert(insts_contains(instr_addr), "wrong nmethod used");
2581 if (is_zombie()) {
2582 // a zombie may never be patched
2583 return false;
2584 }
2585 return true;
2586 }
2587
2588
2589 address nmethod::continuation_for_implicit_exception(address pc) {
2590 // Exception happened outside inline-cache check code => we are inside
2591 // an active nmethod => use cpc to determine a return address
2592 int exception_offset = pc - code_begin();
2593 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2594 #ifdef ASSERT
2595 if (cont_offset == 0) {
2596 Thread* thread = ThreadLocalStorage::get_thread_slow();
2597 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2598 HandleMark hm(thread);
2599 ResourceMark rm(thread);
2600 CodeBlob* cb = CodeCache::find_blob(pc);
2601 assert(cb != NULL && cb == this, "");
2602 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2603 print();
2604 method()->print_codes();
2605 print_code();
2606 print_pcs();
2607 }
2608 #endif
2609 if (cont_offset == 0) {
2610 // Let the normal error handling report the exception
2611 return NULL;
2612 }
2613 return code_begin() + cont_offset;
2614 }
2615
2616
2617
2618 void nmethod_init() {
2619 // make sure you didn't forget to adjust the filler fields
2620 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2621 }
2622
2623
2624 //-------------------------------------------------------------------------------------------
2625
2626
2627 // QQQ might we make this work from a frame??
2628 nmethodLocker::nmethodLocker(address pc) {
2629 CodeBlob* cb = CodeCache::find_blob(pc);
2630 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2631 _nm = (nmethod*)cb;
2632 lock_nmethod(_nm);
2633 }
2634
2635 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2636 // should pass zombie_ok == true.
2637 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2638 if (nm == NULL) return;
2639 Atomic::inc(&nm->_lock_count);
2640 assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2641 }
2642
2643 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2644 if (nm == NULL) return;
2645 Atomic::dec(&nm->_lock_count);
2646 assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2647 }
2648
2649
2650 // -----------------------------------------------------------------------------
2651 // nmethod::get_deopt_original_pc
2652 //
2653 // Return the original PC for the given PC if:
2654 // (a) the given PC belongs to a nmethod and
2655 // (b) it is a deopt PC
2656 address nmethod::get_deopt_original_pc(const frame* fr) {
2657 if (fr->cb() == NULL) return NULL;
2658
2659 nmethod* nm = fr->cb()->as_nmethod_or_null();
2660 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2661 return nm->get_original_pc(fr);
2662
2663 return NULL;
2664 }
2665
2666
2667 // -----------------------------------------------------------------------------
2668 // MethodHandle
2669
2670 bool nmethod::is_method_handle_return(address return_pc) {
2671 if (!has_method_handle_invokes()) return false;
2672 PcDesc* pd = pc_desc_at(return_pc);
2673 if (pd == NULL)
2674 return false;
2675 return pd->is_method_handle_invoke();
2676 }
2677
2678
2679 // -----------------------------------------------------------------------------
2680 // Verification
2681
2682 class VerifyOopsClosure: public OopClosure {
2683 nmethod* _nm;
2684 bool _ok;
2685 public:
2686 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2687 bool ok() { return _ok; }
2688 virtual void do_oop(oop* p) {
2689 if ((*p) == NULL || (*p)->is_oop()) return;
2690 if (_ok) {
2691 _nm->print_nmethod(true);
2692 _ok = false;
2693 }
2694 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2695 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2696 }
2697 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2698 };
2699
2700 void nmethod::verify() {
2701
2702 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2703 // seems odd.
2704
2705 if( is_zombie() || is_not_entrant() )
2706 return;
2707
2708 // Make sure all the entry points are correctly aligned for patching.
2709 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2710
2711 // assert(method()->is_oop(), "must be valid");
2712
2713 ResourceMark rm;
2714
2715 if (!CodeCache::contains(this)) {
2716 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2717 }
2718
2719 if(is_native_method() )
2720 return;
2721
2722 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2723 if (nm != this) {
2724 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2725 this));
2726 }
2727
2728 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2729 if (! p->verify(this)) {
2730 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2731 }
2732 }
2733
2734 VerifyOopsClosure voc(this);
2735 oops_do(&voc);
2736 assert(voc.ok(), "embedded oops must be OK");
2737 verify_scavenge_root_oops();
2738
2739 verify_scopes();
2740 }
2741
2742
2743 void nmethod::verify_interrupt_point(address call_site) {
2744 // Verify IC only when nmethod installation is finished.
2745 bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed
2746 || !this->is_in_use(); // nmethod is installed, but not in 'in_use' state
2747 if (is_installed) {
2748 Thread *cur = Thread::current();
2749 if (CompiledIC_lock->owner() == cur ||
2750 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2751 SafepointSynchronize::is_at_safepoint())) {
2752 CompiledIC_at(this, call_site);
2753 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2754 } else {
2755 MutexLocker ml_verify (CompiledIC_lock);
2756 CompiledIC_at(this, call_site);
2757 }
2758 }
2759
2760 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2761 assert(pd != NULL, "PcDesc must exist");
2762 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2763 pd->obj_decode_offset(), pd->should_reexecute(),
2764 pd->return_oop());
2765 !sd->is_top(); sd = sd->sender()) {
2766 sd->verify();
2767 }
2768 }
2769
2770 void nmethod::verify_scopes() {
2771 if( !method() ) return; // Runtime stubs have no scope
2772 if (method()->is_native()) return; // Ignore stub methods.
2773 // iterate through all interrupt point
2774 // and verify the debug information is valid.
2775 RelocIterator iter((nmethod*)this);
2776 while (iter.next()) {
2777 address stub = NULL;
2778 switch (iter.type()) {
2779 case relocInfo::virtual_call_type:
2780 verify_interrupt_point(iter.addr());
2781 break;
2782 case relocInfo::opt_virtual_call_type:
2783 stub = iter.opt_virtual_call_reloc()->static_stub();
2784 verify_interrupt_point(iter.addr());
2785 break;
2786 case relocInfo::static_call_type:
2787 stub = iter.static_call_reloc()->static_stub();
2788 //verify_interrupt_point(iter.addr());
2789 break;
2790 case relocInfo::runtime_call_type:
2791 address destination = iter.reloc()->value();
2792 // Right now there is no way to find out which entries support
2793 // an interrupt point. It would be nice if we had this
2794 // information in a table.
2795 break;
2796 }
2797 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2798 }
2799 }
2800
2801
2802 // -----------------------------------------------------------------------------
2803 // Non-product code
2804 #ifndef PRODUCT
2805
2806 class DebugScavengeRoot: public OopClosure {
2807 nmethod* _nm;
2808 bool _ok;
2809 public:
2810 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2811 bool ok() { return _ok; }
2812 virtual void do_oop(oop* p) {
2813 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2814 if (_ok) {
2815 _nm->print_nmethod(true);
2816 _ok = false;
2817 }
2818 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2819 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2820 (*p)->print();
2821 }
2822 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2823 };
2824
2825 void nmethod::verify_scavenge_root_oops() {
2826 if (UseG1GC) {
2827 return;
2828 }
2829
2830 if (!on_scavenge_root_list()) {
2831 // Actually look inside, to verify the claim that it's clean.
2832 DebugScavengeRoot debug_scavenge_root(this);
2833 oops_do(&debug_scavenge_root);
2834 if (!debug_scavenge_root.ok())
2835 fatal("found an unadvertised bad scavengable oop in the code cache");
2836 }
2837 assert(scavenge_root_not_marked(), "");
2838 }
2839
2840 #endif // PRODUCT
2841
2842 // Printing operations
2843
2844 void nmethod::print() const {
2845 ResourceMark rm;
2846 ttyLocker ttyl; // keep the following output all in one block
2847
2848 tty->print("Compiled method ");
2849
2850 if (is_compiled_by_c1()) {
2851 tty->print("(c1) ");
2852 } else if (is_compiled_by_c2()) {
2853 tty->print("(c2) ");
2854 } else if (is_compiled_by_shark()) {
2855 tty->print("(shark) ");
2856 } else {
2857 tty->print("(nm) ");
2858 }
2859
2860 print_on(tty, NULL);
2861
2862 if (WizardMode) {
2863 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2864 tty->print(" for method " INTPTR_FORMAT , (address)method());
2865 tty->print(" { ");
2866 if (is_in_use()) tty->print("in_use ");
2867 if (is_not_entrant()) tty->print("not_entrant ");
2868 if (is_zombie()) tty->print("zombie ");
2869 if (is_unloaded()) tty->print("unloaded ");
2870 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2871 tty->print_cr("}:");
2872 }
2873 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2874 (address)this,
2875 (address)this + size(),
2876 size());
2877 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2878 relocation_begin(),
2879 relocation_end(),
2880 relocation_size());
2881 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2882 consts_begin(),
2883 consts_end(),
2884 consts_size());
2885 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2886 insts_begin(),
2887 insts_end(),
2888 insts_size());
2889 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2890 stub_begin(),
2891 stub_end(),
2892 stub_size());
2893 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2894 oops_begin(),
2895 oops_end(),
2896 oops_size());
2897 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2898 metadata_begin(),
2899 metadata_end(),
2900 metadata_size());
2901 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2902 scopes_data_begin(),
2903 scopes_data_end(),
2904 scopes_data_size());
2905 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2906 scopes_pcs_begin(),
2907 scopes_pcs_end(),
2908 scopes_pcs_size());
2909 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2910 dependencies_begin(),
2911 dependencies_end(),
2912 dependencies_size());
2913 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2914 handler_table_begin(),
2915 handler_table_end(),
2916 handler_table_size());
2917 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2918 nul_chk_table_begin(),
2919 nul_chk_table_end(),
2920 nul_chk_table_size());
2921 }
2922
2923 void nmethod::print_code() {
2924 HandleMark hm;
2925 ResourceMark m;
2926 Disassembler::decode(this);
2927 }
2928
2929
2930 #ifndef PRODUCT
2931
2932 void nmethod::print_scopes() {
2933 // Find the first pc desc for all scopes in the code and print it.
2934 ResourceMark rm;
2935 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2936 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2937 continue;
2938
2939 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2940 sd->print_on(tty, p);
2941 }
2942 }
2943
2944 void nmethod::print_dependencies() {
2945 ResourceMark rm;
2946 ttyLocker ttyl; // keep the following output all in one block
2947 tty->print_cr("Dependencies:");
2948 for (Dependencies::DepStream deps(this); deps.next(); ) {
2949 deps.print_dependency();
2950 Klass* ctxk = deps.context_type();
2951 if (ctxk != NULL) {
2952 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2953 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2954 }
2955 }
2956 deps.log_dependency(); // put it into the xml log also
2957 }
2958 }
2959
2960
2961 void nmethod::print_relocations() {
2962 ResourceMark m; // in case methods get printed via the debugger
2963 tty->print_cr("relocations:");
2964 RelocIterator iter(this);
2965 iter.print();
2966 if (UseRelocIndex) {
2967 jint* index_end = (jint*)relocation_end() - 1;
2968 jint index_size = *index_end;
2969 jint* index_start = (jint*)( (address)index_end - index_size );
2970 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2971 if (index_size > 0) {
2972 jint* ip;
2973 for (ip = index_start; ip+2 <= index_end; ip += 2)
2974 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2975 ip[0],
2976 ip[1],
2977 header_end()+ip[0],
2978 relocation_begin()-1+ip[1]);
2979 for (; ip < index_end; ip++)
2980 tty->print_cr(" (%d ?)", ip[0]);
2981 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip);
2982 ip++;
2983 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2984 }
2985 }
2986 }
2987
2988
2989 void nmethod::print_pcs() {
2990 ResourceMark m; // in case methods get printed via debugger
2991 tty->print_cr("pc-bytecode offsets:");
2992 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2993 p->print(this);
2994 }
2995 }
2996
2997 #endif // PRODUCT
2998
2999 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
3000 RelocIterator iter(this, begin, end);
3001 bool have_one = false;
3002 while (iter.next()) {
3003 have_one = true;
3004 switch (iter.type()) {
3005 case relocInfo::none: return "no_reloc";
3006 case relocInfo::oop_type: {
3007 stringStream st;
3008 oop_Relocation* r = iter.oop_reloc();
3009 oop obj = r->oop_value();
3010 st.print("oop(");
3011 if (obj == NULL) st.print("NULL");
3012 else obj->print_value_on(&st);
3013 st.print(")");
3014 return st.as_string();
3015 }
3016 case relocInfo::metadata_type: {
3017 stringStream st;
3018 metadata_Relocation* r = iter.metadata_reloc();
3019 Metadata* obj = r->metadata_value();
3020 st.print("metadata(");
3021 if (obj == NULL) st.print("NULL");
3022 else obj->print_value_on(&st);
3023 st.print(")");
3024 return st.as_string();
3025 }
3026 case relocInfo::virtual_call_type: return "virtual_call";
3027 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
3028 case relocInfo::static_call_type: return "static_call";
3029 case relocInfo::static_stub_type: return "static_stub";
3030 case relocInfo::runtime_call_type: return "runtime_call";
3031 case relocInfo::external_word_type: return "external_word";
3032 case relocInfo::internal_word_type: return "internal_word";
3033 case relocInfo::section_word_type: return "section_word";
3034 case relocInfo::poll_type: return "poll";
3035 case relocInfo::poll_return_type: return "poll_return";
3036 case relocInfo::type_mask: return "type_bit_mask";
3037 }
3038 }
3039 return have_one ? "other" : NULL;
3040 }
3041
3042 // Return a the last scope in (begin..end]
3043 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
3044 PcDesc* p = pc_desc_near(begin+1);
3045 if (p != NULL && p->real_pc(this) <= end) {
3046 return new ScopeDesc(this, p->scope_decode_offset(),
3047 p->obj_decode_offset(), p->should_reexecute(),
3048 p->return_oop());
3049 }
3050 return NULL;
3051 }
3052
3053 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
3054 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
3055 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
3056 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
3057 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
3058 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
3059
3060 if (has_method_handle_invokes())
3061 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
3062
3063 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
3064
3065 if (block_begin == entry_point()) {
3066 methodHandle m = method();
3067 if (m.not_null()) {
3068 stream->print(" # ");
3069 m->print_value_on(stream);
3070 stream->cr();
3071 }
3072 if (m.not_null() && !is_osr_method()) {
3073 ResourceMark rm;
3074 int sizeargs = m->size_of_parameters();
3075 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
3076 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
3077 {
3078 int sig_index = 0;
3079 if (!m->is_static())
3080 sig_bt[sig_index++] = T_OBJECT; // 'this'
3081 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
3082 BasicType t = ss.type();
3083 sig_bt[sig_index++] = t;
3084 if (type2size[t] == 2) {
3085 sig_bt[sig_index++] = T_VOID;
3086 } else {
3087 assert(type2size[t] == 1, "size is 1 or 2");
3088 }
3089 }
3090 assert(sig_index == sizeargs, "");
3091 }
3092 const char* spname = "sp"; // make arch-specific?
3093 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
3094 int stack_slot_offset = this->frame_size() * wordSize;
3095 int tab1 = 14, tab2 = 24;
3096 int sig_index = 0;
3097 int arg_index = (m->is_static() ? 0 : -1);
3098 bool did_old_sp = false;
3099 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
3100 bool at_this = (arg_index == -1);
3101 bool at_old_sp = false;
3102 BasicType t = (at_this ? T_OBJECT : ss.type());
3103 assert(t == sig_bt[sig_index], "sigs in sync");
3104 if (at_this)
3105 stream->print(" # this: ");
3106 else
3107 stream->print(" # parm%d: ", arg_index);
3108 stream->move_to(tab1);
3109 VMReg fst = regs[sig_index].first();
3110 VMReg snd = regs[sig_index].second();
3111 if (fst->is_reg()) {
3112 stream->print("%s", fst->name());
3113 if (snd->is_valid()) {
3114 stream->print(":%s", snd->name());
3115 }
3116 } else if (fst->is_stack()) {
3117 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
3118 if (offset == stack_slot_offset) at_old_sp = true;
3119 stream->print("[%s+0x%x]", spname, offset);
3120 } else {
3121 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
3122 }
3123 stream->print(" ");
3124 stream->move_to(tab2);
3125 stream->print("= ");
3126 if (at_this) {
3127 m->method_holder()->print_value_on(stream);
3128 } else {
3129 bool did_name = false;
3130 if (!at_this && ss.is_object()) {
3131 Symbol* name = ss.as_symbol_or_null();
3132 if (name != NULL) {
3133 name->print_value_on(stream);
3134 did_name = true;
3135 }
3136 }
3137 if (!did_name)
3138 stream->print("%s", type2name(t));
3139 }
3140 if (at_old_sp) {
3141 stream->print(" (%s of caller)", spname);
3142 did_old_sp = true;
3143 }
3144 stream->cr();
3145 sig_index += type2size[t];
3146 arg_index += 1;
3147 if (!at_this) ss.next();
3148 }
3149 if (!did_old_sp) {
3150 stream->print(" # ");
3151 stream->move_to(tab1);
3152 stream->print("[%s+0x%x]", spname, stack_slot_offset);
3153 stream->print(" (%s of caller)", spname);
3154 stream->cr();
3155 }
3156 }
3157 }
3158 }
3159
3160 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
3161 // First, find an oopmap in (begin, end].
3162 // We use the odd half-closed interval so that oop maps and scope descs
3163 // which are tied to the byte after a call are printed with the call itself.
3164 address base = code_begin();
3165 OopMapSet* oms = oop_maps();
3166 if (oms != NULL) {
3167 for (int i = 0, imax = oms->size(); i < imax; i++) {
3168 OopMap* om = oms->at(i);
3169 address pc = base + om->offset();
3170 if (pc > begin) {
3171 if (pc <= end) {
3172 st->move_to(column);
3173 st->print("; ");
3174 om->print_on(st);
3175 }
3176 break;
3177 }
3178 }
3179 }
3180
3181 // Print any debug info present at this pc.
3182 ScopeDesc* sd = scope_desc_in(begin, end);
3183 if (sd != NULL) {
3184 st->move_to(column);
3185 if (sd->bci() == SynchronizationEntryBCI) {
3186 st->print(";*synchronization entry");
3187 } else {
3188 if (sd->method() == NULL) {
3189 st->print("method is NULL");
3190 } else if (sd->method()->is_native()) {
3191 st->print("method is native");
3192 } else {
3193 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
3194 st->print(";*%s", Bytecodes::name(bc));
3195 switch (bc) {
3196 case Bytecodes::_invokevirtual:
3197 case Bytecodes::_invokespecial:
3198 case Bytecodes::_invokestatic:
3199 case Bytecodes::_invokeinterface:
3200 {
3201 Bytecode_invoke invoke(sd->method(), sd->bci());
3202 st->print(" ");
3203 if (invoke.name() != NULL)
3204 invoke.name()->print_symbol_on(st);
3205 else
3206 st->print("<UNKNOWN>");
3207 break;
3208 }
3209 case Bytecodes::_getfield:
3210 case Bytecodes::_putfield:
3211 case Bytecodes::_getstatic:
3212 case Bytecodes::_putstatic:
3213 {
3214 Bytecode_field field(sd->method(), sd->bci());
3215 st->print(" ");
3216 if (field.name() != NULL)
3217 field.name()->print_symbol_on(st);
3218 else
3219 st->print("<UNKNOWN>");
3220 }
3221 }
3222 }
3223 }
3224
3225 // Print all scopes
3226 for (;sd != NULL; sd = sd->sender()) {
3227 st->move_to(column);
3228 st->print("; -");
3229 if (sd->method() == NULL) {
3230 st->print("method is NULL");
3231 } else {
3232 sd->method()->print_short_name(st);
3233 }
3234 int lineno = sd->method()->line_number_from_bci(sd->bci());
3235 if (lineno != -1) {
3236 st->print("@%d (line %d)", sd->bci(), lineno);
3237 } else {
3238 st->print("@%d", sd->bci());
3239 }
3240 st->cr();
3241 }
3242 }
3243
3244 // Print relocation information
3245 const char* str = reloc_string_for(begin, end);
3246 if (str != NULL) {
3247 if (sd != NULL) st->cr();
3248 st->move_to(column);
3249 st->print("; {%s}", str);
3250 }
3251 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
3252 if (cont_offset != 0) {
3253 st->move_to(column);
3254 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
3255 }
3256
3257 }
3258
3259 #ifndef PRODUCT
3260
3261 void nmethod::print_value_on(outputStream* st) const {
3262 st->print("nmethod");
3263 print_on(st, NULL);
3264 }
3265
3266 void nmethod::print_calls(outputStream* st) {
3267 RelocIterator iter(this);
3268 while (iter.next()) {
3269 switch (iter.type()) {
3270 case relocInfo::virtual_call_type:
3271 case relocInfo::opt_virtual_call_type: {
3272 VerifyMutexLocker mc(CompiledIC_lock);
3273 CompiledIC_at(&iter)->print();
3274 break;
3275 }
3276 case relocInfo::static_call_type:
3277 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
3278 compiledStaticCall_at(iter.reloc())->print();
3279 break;
3280 }
3281 }
3282 }
3283
3284 void nmethod::print_handler_table() {
3285 ExceptionHandlerTable(this).print();
3286 }
3287
3288 void nmethod::print_nul_chk_table() {
3289 ImplicitExceptionTable(this).print(code_begin());
3290 }
3291
3292 void nmethod::print_statistics() {
3293 ttyLocker ttyl;
3294 if (xtty != NULL) xtty->head("statistics type='nmethod'");
3295 nmethod_stats.print_native_nmethod_stats();
3296 nmethod_stats.print_nmethod_stats();
3297 DebugInformationRecorder::print_statistics();
3298 nmethod_stats.print_pc_stats();
3299 Dependencies::print_statistics();
3300 if (xtty != NULL) xtty->tail("statistics");
3301 }
3302
3303 #endif // PRODUCT