1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "code/codeCache.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/dependencies.hpp"
29 #include "code/nmethod.hpp"
30 #include "code/scopeDesc.hpp"
31 #include "compiler/abstractCompiler.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/compileLog.hpp"
34 #include "compiler/compilerOracle.hpp"
35 #include "compiler/disassembler.hpp"
36 #include "interpreter/bytecode.hpp"
37 #include "oops/methodData.hpp"
38 #include "prims/jvmtiRedefineClassesTrace.hpp"
39 #include "prims/jvmtiImpl.hpp"
40 #include "runtime/sharedRuntime.hpp"
41 #include "runtime/sweeper.hpp"
42 #include "utilities/resourceHash.hpp"
43 #include "utilities/dtrace.hpp"
44 #include "utilities/events.hpp"
45 #include "utilities/xmlstream.hpp"
46 #ifdef SHARK
47 #include "shark/sharkCompiler.hpp"
48 #endif
49
50 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
51
52 #ifdef DTRACE_ENABLED
53
54 // Only bother with this argument setup if dtrace is available
55
56 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
57 { \
58 Method* m = (method); \
59 if (m != NULL) { \
60 Symbol* klass_name = m->klass_name(); \
61 Symbol* name = m->name(); \
62 Symbol* signature = m->signature(); \
63 HOTSPOT_COMPILED_METHOD_UNLOAD( \
64 (char *) klass_name->bytes(), klass_name->utf8_length(), \
65 (char *) name->bytes(), name->utf8_length(), \
66 (char *) signature->bytes(), signature->utf8_length()); \
67 } \
68 }
69
70 #else // ndef DTRACE_ENABLED
71
72 #define DTRACE_METHOD_UNLOAD_PROBE(method)
73
74 #endif
75
76 bool nmethod::is_compiled_by_c1() const {
77 if (compiler() == NULL) {
78 return false;
79 }
80 return compiler()->is_c1();
81 }
82 bool nmethod::is_compiled_by_c2() const {
83 if (compiler() == NULL) {
84 return false;
85 }
86 return compiler()->is_c2();
87 }
88 bool nmethod::is_compiled_by_shark() const {
89 if (compiler() == NULL) {
90 return false;
91 }
92 return compiler()->is_shark();
93 }
94
95
96
97 //---------------------------------------------------------------------------------
98 // NMethod statistics
99 // They are printed under various flags, including:
100 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
101 // (In the latter two cases, they like other stats are printed to the log only.)
102
103 #ifndef PRODUCT
104 // These variables are put into one block to reduce relocations
105 // and make it simpler to print from the debugger.
106 static
107 struct nmethod_stats_struct {
108 int nmethod_count;
109 int total_size;
110 int relocation_size;
111 int consts_size;
112 int insts_size;
113 int stub_size;
114 int scopes_data_size;
115 int scopes_pcs_size;
116 int dependencies_size;
117 int handler_table_size;
118 int nul_chk_table_size;
119 int oops_size;
120
121 void note_nmethod(nmethod* nm) {
122 nmethod_count += 1;
123 total_size += nm->size();
124 relocation_size += nm->relocation_size();
125 consts_size += nm->consts_size();
126 insts_size += nm->insts_size();
127 stub_size += nm->stub_size();
128 oops_size += nm->oops_size();
129 scopes_data_size += nm->scopes_data_size();
130 scopes_pcs_size += nm->scopes_pcs_size();
131 dependencies_size += nm->dependencies_size();
132 handler_table_size += nm->handler_table_size();
133 nul_chk_table_size += nm->nul_chk_table_size();
134 }
135 void print_nmethod_stats() {
136 if (nmethod_count == 0) return;
137 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
138 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
139 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
140 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
141 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size);
142 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
143 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
144 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
145 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
146 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
147 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
148 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
149 }
150
151 int native_nmethod_count;
152 int native_total_size;
153 int native_relocation_size;
154 int native_insts_size;
155 int native_oops_size;
156 void note_native_nmethod(nmethod* nm) {
157 native_nmethod_count += 1;
158 native_total_size += nm->size();
159 native_relocation_size += nm->relocation_size();
160 native_insts_size += nm->insts_size();
161 native_oops_size += nm->oops_size();
162 }
163 void print_native_nmethod_stats() {
164 if (native_nmethod_count == 0) return;
165 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
166 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
167 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
168 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size);
169 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
170 }
171
172 int pc_desc_resets; // number of resets (= number of caches)
173 int pc_desc_queries; // queries to nmethod::find_pc_desc
174 int pc_desc_approx; // number of those which have approximate true
175 int pc_desc_repeats; // number of _pc_descs[0] hits
176 int pc_desc_hits; // number of LRU cache hits
177 int pc_desc_tests; // total number of PcDesc examinations
178 int pc_desc_searches; // total number of quasi-binary search steps
179 int pc_desc_adds; // number of LUR cache insertions
180
181 void print_pc_stats() {
182 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
183 pc_desc_queries,
184 (double)(pc_desc_tests + pc_desc_searches)
185 / pc_desc_queries);
186 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
187 pc_desc_resets,
188 pc_desc_queries, pc_desc_approx,
189 pc_desc_repeats, pc_desc_hits,
190 pc_desc_tests, pc_desc_searches, pc_desc_adds);
191 }
192 } nmethod_stats;
193 #endif //PRODUCT
194
195
196 //---------------------------------------------------------------------------------
197
198
199 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
200 assert(pc != NULL, "Must be non null");
201 assert(exception.not_null(), "Must be non null");
202 assert(handler != NULL, "Must be non null");
203
204 _count = 0;
205 _exception_type = exception->klass();
206 _next = NULL;
207
208 add_address_and_handler(pc,handler);
209 }
210
211
212 address ExceptionCache::match(Handle exception, address pc) {
213 assert(pc != NULL,"Must be non null");
214 assert(exception.not_null(),"Must be non null");
215 if (exception->klass() == exception_type()) {
216 return (test_address(pc));
217 }
218
219 return NULL;
220 }
221
222
223 bool ExceptionCache::match_exception_with_space(Handle exception) {
224 assert(exception.not_null(),"Must be non null");
225 if (exception->klass() == exception_type() && count() < cache_size) {
226 return true;
227 }
228 return false;
229 }
230
231
232 address ExceptionCache::test_address(address addr) {
233 for (int i=0; i<count(); i++) {
234 if (pc_at(i) == addr) {
235 return handler_at(i);
236 }
237 }
238 return NULL;
239 }
240
241
242 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
243 if (test_address(addr) == handler) return true;
244 if (count() < cache_size) {
245 set_pc_at(count(),addr);
246 set_handler_at(count(), handler);
247 increment_count();
248 return true;
249 }
250 return false;
251 }
252
253
254 // private method for handling exception cache
255 // These methods are private, and used to manipulate the exception cache
256 // directly.
257 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
258 ExceptionCache* ec = exception_cache();
259 while (ec != NULL) {
260 if (ec->match_exception_with_space(exception)) {
261 return ec;
262 }
263 ec = ec->next();
264 }
265 return NULL;
266 }
267
268
269 //-----------------------------------------------------------------------------
270
271
272 // Helper used by both find_pc_desc methods.
273 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
274 NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
275 if (!approximate)
276 return pc->pc_offset() == pc_offset;
277 else
278 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
279 }
280
281 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
282 if (initial_pc_desc == NULL) {
283 _pc_descs[0] = NULL; // native method; no PcDescs at all
284 return;
285 }
286 NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
287 // reset the cache by filling it with benign (non-null) values
288 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
289 for (int i = 0; i < cache_size; i++)
290 _pc_descs[i] = initial_pc_desc;
291 }
292
293 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
294 NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
295 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
296
297 // Note: one might think that caching the most recently
298 // read value separately would be a win, but one would be
299 // wrong. When many threads are updating it, the cache
300 // line it's in would bounce between caches, negating
301 // any benefit.
302
303 // In order to prevent race conditions do not load cache elements
304 // repeatedly, but use a local copy:
305 PcDesc* res;
306
307 // Step one: Check the most recently added value.
308 res = _pc_descs[0];
309 if (res == NULL) return NULL; // native method; no PcDescs at all
310 if (match_desc(res, pc_offset, approximate)) {
311 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
312 return res;
313 }
314
315 // Step two: Check the rest of the LRU cache.
316 for (int i = 1; i < cache_size; ++i) {
317 res = _pc_descs[i];
318 if (res->pc_offset() < 0) break; // optimization: skip empty cache
319 if (match_desc(res, pc_offset, approximate)) {
320 NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
321 return res;
322 }
323 }
324
325 // Report failure.
326 return NULL;
327 }
328
329 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
330 NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
331 // Update the LRU cache by shifting pc_desc forward.
332 for (int i = 0; i < cache_size; i++) {
333 PcDesc* next = _pc_descs[i];
334 _pc_descs[i] = pc_desc;
335 pc_desc = next;
336 }
337 }
338
339 // adjust pcs_size so that it is a multiple of both oopSize and
340 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
341 // of oopSize, then 2*sizeof(PcDesc) is)
342 static int adjust_pcs_size(int pcs_size) {
343 int nsize = round_to(pcs_size, oopSize);
344 if ((nsize % sizeof(PcDesc)) != 0) {
345 nsize = pcs_size + sizeof(PcDesc);
346 }
347 assert((nsize % oopSize) == 0, "correct alignment");
348 return nsize;
349 }
350
351 //-----------------------------------------------------------------------------
352
353
354 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
355 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
356 assert(new_entry != NULL,"Must be non null");
357 assert(new_entry->next() == NULL, "Must be null");
358
359 if (exception_cache() != NULL) {
360 new_entry->set_next(exception_cache());
361 }
362 set_exception_cache(new_entry);
363 }
364
365 void nmethod::remove_from_exception_cache(ExceptionCache* ec) {
366 ExceptionCache* prev = NULL;
367 ExceptionCache* curr = exception_cache();
368 assert(curr != NULL, "nothing to remove");
369 // find the previous and next entry of ec
370 while (curr != ec) {
371 prev = curr;
372 curr = curr->next();
373 assert(curr != NULL, "ExceptionCache not found");
374 }
375 // now: curr == ec
376 ExceptionCache* next = curr->next();
377 if (prev == NULL) {
378 set_exception_cache(next);
379 } else {
380 prev->set_next(next);
381 }
382 delete curr;
383 }
384
385
386 // public method for accessing the exception cache
387 // These are the public access methods.
388 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
389 // We never grab a lock to read the exception cache, so we may
390 // have false negatives. This is okay, as it can only happen during
391 // the first few exception lookups for a given nmethod.
392 ExceptionCache* ec = exception_cache();
393 while (ec != NULL) {
394 address ret_val;
395 if ((ret_val = ec->match(exception,pc)) != NULL) {
396 return ret_val;
397 }
398 ec = ec->next();
399 }
400 return NULL;
401 }
402
403
404 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
405 // There are potential race conditions during exception cache updates, so we
406 // must own the ExceptionCache_lock before doing ANY modifications. Because
407 // we don't lock during reads, it is possible to have several threads attempt
408 // to update the cache with the same data. We need to check for already inserted
409 // copies of the current data before adding it.
410
411 MutexLocker ml(ExceptionCache_lock);
412 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
413
414 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
415 target_entry = new ExceptionCache(exception,pc,handler);
416 add_exception_cache_entry(target_entry);
417 }
418 }
419
420
421 //-------------end of code for ExceptionCache--------------
422
423
424 int nmethod::total_size() const {
425 return
426 consts_size() +
427 insts_size() +
428 stub_size() +
429 scopes_data_size() +
430 scopes_pcs_size() +
431 handler_table_size() +
432 nul_chk_table_size();
433 }
434
435 const char* nmethod::compile_kind() const {
436 if (is_osr_method()) return "osr";
437 if (method() != NULL && is_native_method()) return "c2n";
438 return NULL;
439 }
440
441 // Fill in default values for various flag fields
442 void nmethod::init_defaults() {
443 _state = in_use;
444 _marked_for_reclamation = 0;
445 _has_flushed_dependencies = 0;
446 _has_unsafe_access = 0;
447 _has_method_handle_invokes = 0;
448 _lazy_critical_native = 0;
449 _has_wide_vectors = 0;
450 _marked_for_deoptimization = 0;
451 _lock_count = 0;
452 _stack_traversal_mark = 0;
453 _unload_reported = false; // jvmti state
454
455 #ifdef ASSERT
456 _oops_are_stale = false;
457 #endif
458
459 _oops_do_mark_link = NULL;
460 _jmethod_id = NULL;
461 _osr_link = NULL;
462 _scavenge_root_link = NULL;
463 _scavenge_root_state = 0;
464 _compiler = NULL;
465 #if INCLUDE_RTM_OPT
466 _rtm_state = NoRTM;
467 #endif
468 #ifdef HAVE_DTRACE_H
469 _trap_offset = 0;
470 #endif // def HAVE_DTRACE_H
471 }
472
473 nmethod* nmethod::new_native_nmethod(methodHandle method,
474 int compile_id,
475 CodeBuffer *code_buffer,
476 int vep_offset,
477 int frame_complete,
478 int frame_size,
479 ByteSize basic_lock_owner_sp_offset,
480 ByteSize basic_lock_sp_offset,
481 OopMapSet* oop_maps) {
482 code_buffer->finalize_oop_references(method);
483 // create nmethod
484 nmethod* nm = NULL;
485 {
486 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
487 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
488 CodeOffsets offsets;
489 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
490 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
491 nm = new (native_nmethod_size) nmethod(method(), native_nmethod_size,
492 compile_id, &offsets,
493 code_buffer, frame_size,
494 basic_lock_owner_sp_offset,
495 basic_lock_sp_offset, oop_maps);
496 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm));
497 if (PrintAssembly && nm != NULL) {
498 Disassembler::decode(nm);
499 }
500 }
501 // verify nmethod
502 debug_only(if (nm) nm->verify();) // might block
503
504 if (nm != NULL) {
505 nm->log_new_nmethod();
506 }
507
508 return nm;
509 }
510
511 #ifdef HAVE_DTRACE_H
512 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
513 CodeBuffer *code_buffer,
514 int vep_offset,
515 int trap_offset,
516 int frame_complete,
517 int frame_size) {
518 code_buffer->finalize_oop_references(method);
519 // create nmethod
520 nmethod* nm = NULL;
521 {
522 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
523 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
524 CodeOffsets offsets;
525 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
526 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
527 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
528
529 nm = new (nmethod_size) nmethod(method(), nmethod_size,
530 &offsets, code_buffer, frame_size);
531
532 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
533 if (PrintAssembly && nm != NULL) {
534 Disassembler::decode(nm);
535 }
536 }
537 // verify nmethod
538 debug_only(if (nm) nm->verify();) // might block
539
540 if (nm != NULL) {
541 nm->log_new_nmethod();
542 }
543
544 return nm;
545 }
546
547 #endif // def HAVE_DTRACE_H
548
549 nmethod* nmethod::new_nmethod(methodHandle method,
550 int compile_id,
551 int entry_bci,
552 CodeOffsets* offsets,
553 int orig_pc_offset,
554 DebugInformationRecorder* debug_info,
555 Dependencies* dependencies,
556 CodeBuffer* code_buffer, int frame_size,
557 OopMapSet* oop_maps,
558 ExceptionHandlerTable* handler_table,
559 ImplicitExceptionTable* nul_chk_table,
560 AbstractCompiler* compiler,
561 int comp_level
562 )
563 {
564 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
565 code_buffer->finalize_oop_references(method);
566 // create nmethod
567 nmethod* nm = NULL;
568 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
569 int nmethod_size =
570 allocation_size(code_buffer, sizeof(nmethod))
571 + adjust_pcs_size(debug_info->pcs_size())
572 + round_to(dependencies->size_in_bytes() , oopSize)
573 + round_to(handler_table->size_in_bytes(), oopSize)
574 + round_to(nul_chk_table->size_in_bytes(), oopSize)
575 + round_to(debug_info->data_size() , oopSize);
576
577 nm = new (nmethod_size)
578 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
579 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
580 oop_maps,
581 handler_table,
582 nul_chk_table,
583 compiler,
584 comp_level);
585
586 if (nm != NULL) {
587 // To make dependency checking during class loading fast, record
588 // the nmethod dependencies in the classes it is dependent on.
589 // This allows the dependency checking code to simply walk the
590 // class hierarchy above the loaded class, checking only nmethods
591 // which are dependent on those classes. The slow way is to
592 // check every nmethod for dependencies which makes it linear in
593 // the number of methods compiled. For applications with a lot
594 // classes the slow way is too slow.
595 for (Dependencies::DepStream deps(nm); deps.next(); ) {
596 Klass* klass = deps.context_type();
597 if (klass == NULL) {
598 continue; // ignore things like evol_method
599 }
600
601 // record this nmethod as dependent on this klass
602 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
603 }
604 NOT_PRODUCT(nmethod_stats.note_nmethod(nm));
605 if (PrintAssembly || CompilerOracle::has_option_string(method, "PrintAssembly")) {
606 Disassembler::decode(nm);
607 }
608 }
609 }
610 // Do verification and logging outside CodeCache_lock.
611 if (nm != NULL) {
612 // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
613 DEBUG_ONLY(nm->verify();)
614 nm->log_new_nmethod();
615 }
616 return nm;
617 }
618
619
620 // For native wrappers
621 nmethod::nmethod(
622 Method* method,
623 int nmethod_size,
624 int compile_id,
625 CodeOffsets* offsets,
626 CodeBuffer* code_buffer,
627 int frame_size,
628 ByteSize basic_lock_owner_sp_offset,
629 ByteSize basic_lock_sp_offset,
630 OopMapSet* oop_maps )
631 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
632 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
633 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
634 _native_basic_lock_sp_offset(basic_lock_sp_offset)
635 {
636 {
637 debug_only(No_Safepoint_Verifier nsv;)
638 assert_locked_or_safepoint(CodeCache_lock);
639
640 init_defaults();
641 _method = method;
642 _entry_bci = InvocationEntryBci;
643 // We have no exception handler or deopt handler make the
644 // values something that will never match a pc like the nmethod vtable entry
645 _exception_offset = 0;
646 _deoptimize_offset = 0;
647 _deoptimize_mh_offset = 0;
648 _orig_pc_offset = 0;
649
650 _consts_offset = data_offset();
651 _stub_offset = data_offset();
652 _oops_offset = data_offset();
653 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
654 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
655 _scopes_pcs_offset = _scopes_data_offset;
656 _dependencies_offset = _scopes_pcs_offset;
657 _handler_table_offset = _dependencies_offset;
658 _nul_chk_table_offset = _handler_table_offset;
659 _nmethod_end_offset = _nul_chk_table_offset;
660 _compile_id = compile_id;
661 _comp_level = CompLevel_none;
662 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
663 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
664 _osr_entry_point = NULL;
665 _exception_cache = NULL;
666 _pc_desc_cache.reset_to(NULL);
667 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
668
669 code_buffer->copy_values_to(this);
670 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
671 CodeCache::add_scavenge_root_nmethod(this);
672 Universe::heap()->register_nmethod(this);
673 }
674 debug_only(verify_scavenge_root_oops());
675 CodeCache::commit(this);
676 }
677
678 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
679 ttyLocker ttyl; // keep the following output all in one block
680 // This output goes directly to the tty, not the compiler log.
681 // To enable tools to match it up with the compilation activity,
682 // be sure to tag this tty output with the compile ID.
683 if (xtty != NULL) {
684 xtty->begin_head("print_native_nmethod");
685 xtty->method(_method);
686 xtty->stamp();
687 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
688 }
689 // print the header part first
690 print();
691 // then print the requested information
692 if (PrintNativeNMethods) {
693 print_code();
694 if (oop_maps != NULL) {
695 oop_maps->print();
696 }
697 }
698 if (PrintRelocations) {
699 print_relocations();
700 }
701 if (xtty != NULL) {
702 xtty->tail("print_native_nmethod");
703 }
704 }
705 }
706
707 // For dtrace wrappers
708 #ifdef HAVE_DTRACE_H
709 nmethod::nmethod(
710 Method* method,
711 int nmethod_size,
712 CodeOffsets* offsets,
713 CodeBuffer* code_buffer,
714 int frame_size)
715 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
716 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
717 _native_receiver_sp_offset(in_ByteSize(-1)),
718 _native_basic_lock_sp_offset(in_ByteSize(-1))
719 {
720 {
721 debug_only(No_Safepoint_Verifier nsv;)
722 assert_locked_or_safepoint(CodeCache_lock);
723
724 init_defaults();
725 _method = method;
726 _entry_bci = InvocationEntryBci;
727 // We have no exception handler or deopt handler make the
728 // values something that will never match a pc like the nmethod vtable entry
729 _exception_offset = 0;
730 _deoptimize_offset = 0;
731 _deoptimize_mh_offset = 0;
732 _unwind_handler_offset = -1;
733 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
734 _orig_pc_offset = 0;
735 _consts_offset = data_offset();
736 _stub_offset = data_offset();
737 _oops_offset = data_offset();
738 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
739 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
740 _scopes_pcs_offset = _scopes_data_offset;
741 _dependencies_offset = _scopes_pcs_offset;
742 _handler_table_offset = _dependencies_offset;
743 _nul_chk_table_offset = _handler_table_offset;
744 _nmethod_end_offset = _nul_chk_table_offset;
745 _compile_id = 0; // default
746 _comp_level = CompLevel_none;
747 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
748 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
749 _osr_entry_point = NULL;
750 _exception_cache = NULL;
751 _pc_desc_cache.reset_to(NULL);
752 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
753
754 code_buffer->copy_values_to(this);
755 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
756 CodeCache::add_scavenge_root_nmethod(this);
757 Universe::heap()->register_nmethod(this);
758 }
759 DEBUG_ONLY(verify_scavenge_root_oops();)
760 CodeCache::commit(this);
761 }
762
763 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
764 ttyLocker ttyl; // keep the following output all in one block
765 // This output goes directly to the tty, not the compiler log.
766 // To enable tools to match it up with the compilation activity,
767 // be sure to tag this tty output with the compile ID.
768 if (xtty != NULL) {
769 xtty->begin_head("print_dtrace_nmethod");
770 xtty->method(_method);
771 xtty->stamp();
772 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
773 }
774 // print the header part first
775 print();
776 // then print the requested information
777 if (PrintNMethods) {
778 print_code();
779 }
780 if (PrintRelocations) {
781 print_relocations();
782 }
783 if (xtty != NULL) {
784 xtty->tail("print_dtrace_nmethod");
785 }
786 }
787 }
788 #endif // def HAVE_DTRACE_H
789
790 void* nmethod::operator new(size_t size, int nmethod_size) throw() {
791 // Not critical, may return null if there is too little continuous memory
792 return CodeCache::allocate(nmethod_size);
793 }
794
795 nmethod::nmethod(
796 Method* method,
797 int nmethod_size,
798 int compile_id,
799 int entry_bci,
800 CodeOffsets* offsets,
801 int orig_pc_offset,
802 DebugInformationRecorder* debug_info,
803 Dependencies* dependencies,
804 CodeBuffer *code_buffer,
805 int frame_size,
806 OopMapSet* oop_maps,
807 ExceptionHandlerTable* handler_table,
808 ImplicitExceptionTable* nul_chk_table,
809 AbstractCompiler* compiler,
810 int comp_level
811 )
812 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
813 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
814 _native_receiver_sp_offset(in_ByteSize(-1)),
815 _native_basic_lock_sp_offset(in_ByteSize(-1))
816 {
817 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
818 {
819 debug_only(No_Safepoint_Verifier nsv;)
820 assert_locked_or_safepoint(CodeCache_lock);
821
822 init_defaults();
823 _method = method;
824 _entry_bci = entry_bci;
825 _compile_id = compile_id;
826 _comp_level = comp_level;
827 _compiler = compiler;
828 _orig_pc_offset = orig_pc_offset;
829 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
830
831 // Section offsets
832 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
833 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
834
835 // Exception handler and deopt handler are in the stub section
836 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
837 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
838 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
839 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
840 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
841 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
842 } else {
843 _deoptimize_mh_offset = -1;
844 }
845 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
846 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
847 } else {
848 _unwind_handler_offset = -1;
849 }
850
851 _oops_offset = data_offset();
852 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
853 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
854
855 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
856 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
857 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
858 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
859 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
860
861 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
862 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
863 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
864 _exception_cache = NULL;
865 _pc_desc_cache.reset_to(scopes_pcs_begin());
866
867 // Copy contents of ScopeDescRecorder to nmethod
868 code_buffer->copy_values_to(this);
869 debug_info->copy_to(this);
870 dependencies->copy_to(this);
871 if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
872 CodeCache::add_scavenge_root_nmethod(this);
873 Universe::heap()->register_nmethod(this);
874 }
875 debug_only(verify_scavenge_root_oops());
876
877 CodeCache::commit(this);
878
879 // Copy contents of ExceptionHandlerTable to nmethod
880 handler_table->copy_to(this);
881 nul_chk_table->copy_to(this);
882
883 // we use the information of entry points to find out if a method is
884 // static or non static
885 assert(compiler->is_c2() ||
886 _method->is_static() == (entry_point() == _verified_entry_point),
887 " entry points must be same for static methods and vice versa");
888 }
889
890 bool printnmethods = PrintNMethods
891 || CompilerOracle::should_print(_method)
892 || CompilerOracle::has_option_string(_method, "PrintNMethods");
893 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
894 print_nmethod(printnmethods);
895 }
896 }
897
898
899 // Print a short set of xml attributes to identify this nmethod. The
900 // output should be embedded in some other element.
901 void nmethod::log_identity(xmlStream* log) const {
902 log->print(" compile_id='%d'", compile_id());
903 const char* nm_kind = compile_kind();
904 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
905 if (compiler() != NULL) {
906 log->print(" compiler='%s'", compiler()->name());
907 }
908 if (TieredCompilation) {
909 log->print(" level='%d'", comp_level());
910 }
911 }
912
913
914 #define LOG_OFFSET(log, name) \
915 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
916 log->print(" " XSTR(name) "_offset='%d'" , \
917 (intptr_t)name##_begin() - (intptr_t)this)
918
919
920 void nmethod::log_new_nmethod() const {
921 if (LogCompilation && xtty != NULL) {
922 ttyLocker ttyl;
923 HandleMark hm;
924 xtty->begin_elem("nmethod");
925 log_identity(xtty);
926 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
927 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
928
929 LOG_OFFSET(xtty, relocation);
930 LOG_OFFSET(xtty, consts);
931 LOG_OFFSET(xtty, insts);
932 LOG_OFFSET(xtty, stub);
933 LOG_OFFSET(xtty, scopes_data);
934 LOG_OFFSET(xtty, scopes_pcs);
935 LOG_OFFSET(xtty, dependencies);
936 LOG_OFFSET(xtty, handler_table);
937 LOG_OFFSET(xtty, nul_chk_table);
938 LOG_OFFSET(xtty, oops);
939
940 xtty->method(method());
941 xtty->stamp();
942 xtty->end_elem();
943 }
944 }
945
946 #undef LOG_OFFSET
947
948
949 // Print out more verbose output usually for a newly created nmethod.
950 void nmethod::print_on(outputStream* st, const char* msg) const {
951 if (st != NULL) {
952 ttyLocker ttyl;
953 if (WizardMode) {
954 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
955 st->print_cr(" (" INTPTR_FORMAT ")", this);
956 } else {
957 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
958 }
959 }
960 }
961
962
963 void nmethod::print_nmethod(bool printmethod) {
964 ttyLocker ttyl; // keep the following output all in one block
965 if (xtty != NULL) {
966 xtty->begin_head("print_nmethod");
967 xtty->stamp();
968 xtty->end_head();
969 }
970 // print the header part first
971 print();
972 // then print the requested information
973 if (printmethod) {
974 print_code();
975 print_pcs();
976 if (oop_maps()) {
977 oop_maps()->print();
978 }
979 }
980 if (PrintDebugInfo) {
981 print_scopes();
982 }
983 if (PrintRelocations) {
984 print_relocations();
985 }
986 if (PrintDependencies) {
987 print_dependencies();
988 }
989 if (PrintExceptionHandlers) {
990 print_handler_table();
991 print_nul_chk_table();
992 }
993 if (xtty != NULL) {
994 xtty->tail("print_nmethod");
995 }
996 }
997
998
999 // Promote one word from an assembly-time handle to a live embedded oop.
1000 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1001 if (handle == NULL ||
1002 // As a special case, IC oops are initialized to 1 or -1.
1003 handle == (jobject) Universe::non_oop_word()) {
1004 (*dest) = (oop) handle;
1005 } else {
1006 (*dest) = JNIHandles::resolve_non_null(handle);
1007 }
1008 }
1009
1010
1011 // Have to have the same name because it's called by a template
1012 void nmethod::copy_values(GrowableArray<jobject>* array) {
1013 int length = array->length();
1014 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1015 oop* dest = oops_begin();
1016 for (int index = 0 ; index < length; index++) {
1017 initialize_immediate_oop(&dest[index], array->at(index));
1018 }
1019
1020 // Now we can fix up all the oops in the code. We need to do this
1021 // in the code because the assembler uses jobjects as placeholders.
1022 // The code and relocations have already been initialized by the
1023 // CodeBlob constructor, so it is valid even at this early point to
1024 // iterate over relocations and patch the code.
1025 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1026 }
1027
1028 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1029 int length = array->length();
1030 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1031 Metadata** dest = metadata_begin();
1032 for (int index = 0 ; index < length; index++) {
1033 dest[index] = array->at(index);
1034 }
1035 }
1036
1037 bool nmethod::is_at_poll_return(address pc) {
1038 RelocIterator iter(this, pc, pc+1);
1039 while (iter.next()) {
1040 if (iter.type() == relocInfo::poll_return_type)
1041 return true;
1042 }
1043 return false;
1044 }
1045
1046
1047 bool nmethod::is_at_poll_or_poll_return(address pc) {
1048 RelocIterator iter(this, pc, pc+1);
1049 while (iter.next()) {
1050 relocInfo::relocType t = iter.type();
1051 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1052 return true;
1053 }
1054 return false;
1055 }
1056
1057
1058 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1059 // re-patch all oop-bearing instructions, just in case some oops moved
1060 RelocIterator iter(this, begin, end);
1061 while (iter.next()) {
1062 if (iter.type() == relocInfo::oop_type) {
1063 oop_Relocation* reloc = iter.oop_reloc();
1064 if (initialize_immediates && reloc->oop_is_immediate()) {
1065 oop* dest = reloc->oop_addr();
1066 initialize_immediate_oop(dest, (jobject) *dest);
1067 }
1068 // Refresh the oop-related bits of this instruction.
1069 reloc->fix_oop_relocation();
1070 } else if (iter.type() == relocInfo::metadata_type) {
1071 metadata_Relocation* reloc = iter.metadata_reloc();
1072 reloc->fix_metadata_relocation();
1073 }
1074 }
1075 }
1076
1077
1078 void nmethod::verify_oop_relocations() {
1079 // Ensure sure that the code matches the current oop values
1080 RelocIterator iter(this, NULL, NULL);
1081 while (iter.next()) {
1082 if (iter.type() == relocInfo::oop_type) {
1083 oop_Relocation* reloc = iter.oop_reloc();
1084 if (!reloc->oop_is_immediate()) {
1085 reloc->verify_oop_relocation();
1086 }
1087 }
1088 }
1089 }
1090
1091
1092 ScopeDesc* nmethod::scope_desc_at(address pc) {
1093 PcDesc* pd = pc_desc_at(pc);
1094 guarantee(pd != NULL, "scope must be present");
1095 return new ScopeDesc(this, pd->scope_decode_offset(),
1096 pd->obj_decode_offset(), pd->should_reexecute(),
1097 pd->return_oop());
1098 }
1099
1100
1101 void nmethod::clear_inline_caches() {
1102 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1103 if (is_zombie()) {
1104 return;
1105 }
1106
1107 RelocIterator iter(this);
1108 while (iter.next()) {
1109 iter.reloc()->clear_inline_cache();
1110 }
1111 }
1112
1113
1114 void nmethod::cleanup_inline_caches() {
1115
1116 assert_locked_or_safepoint(CompiledIC_lock);
1117
1118 // If the method is not entrant or zombie then a JMP is plastered over the
1119 // first few bytes. If an oop in the old code was there, that oop
1120 // should not get GC'd. Skip the first few bytes of oops on
1121 // not-entrant methods.
1122 address low_boundary = verified_entry_point();
1123 if (!is_in_use()) {
1124 low_boundary += NativeJump::instruction_size;
1125 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1126 // This means that the low_boundary is going to be a little too high.
1127 // This shouldn't matter, since oops of non-entrant methods are never used.
1128 // In fact, why are we bothering to look at oops in a non-entrant method??
1129 }
1130
1131 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1132 ResourceMark rm;
1133 RelocIterator iter(this, low_boundary);
1134 while(iter.next()) {
1135 switch(iter.type()) {
1136 case relocInfo::virtual_call_type:
1137 case relocInfo::opt_virtual_call_type: {
1138 CompiledIC *ic = CompiledIC_at(iter.reloc());
1139 // Ok, to lookup references to zombies here
1140 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1141 if( cb != NULL && cb->is_nmethod() ) {
1142 nmethod* nm = (nmethod*)cb;
1143 // Clean inline caches pointing to both zombie and not_entrant methods
1144 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1145 }
1146 break;
1147 }
1148 case relocInfo::static_call_type: {
1149 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1150 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1151 if( cb != NULL && cb->is_nmethod() ) {
1152 nmethod* nm = (nmethod*)cb;
1153 // Clean inline caches pointing to both zombie and not_entrant methods
1154 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1155 }
1156 break;
1157 }
1158 }
1159 }
1160 }
1161
1162 // This is a private interface with the sweeper.
1163 void nmethod::mark_as_seen_on_stack() {
1164 assert(is_alive(), "Must be an alive method");
1165 // Set the traversal mark to ensure that the sweeper does 2
1166 // cleaning passes before moving to zombie.
1167 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1168 }
1169
1170 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1171 // there are no activations on the stack, not in use by the VM,
1172 // and not in use by the ServiceThread)
1173 bool nmethod::can_not_entrant_be_converted() {
1174 assert(is_not_entrant(), "must be a non-entrant method");
1175
1176 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1177 // count can be greater than the stack traversal count before it hits the
1178 // nmethod for the second time.
1179 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1180 !is_locked_by_vm();
1181 }
1182
1183 void nmethod::inc_decompile_count() {
1184 if (!is_compiled_by_c2()) return;
1185 // Could be gated by ProfileTraps, but do not bother...
1186 Method* m = method();
1187 if (m == NULL) return;
1188 MethodData* mdo = m->method_data();
1189 if (mdo == NULL) return;
1190 // There is a benign race here. See comments in methodData.hpp.
1191 mdo->inc_decompile_count();
1192 }
1193
1194 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1195
1196 post_compiled_method_unload();
1197
1198 // Since this nmethod is being unloaded, make sure that dependencies
1199 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1200 // indicate that this work is being done during a GC.
1201 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1202 assert(is_alive != NULL, "Should be non-NULL");
1203 // A non-NULL is_alive closure indicates that this is being called during GC.
1204 flush_dependencies(is_alive);
1205
1206 // Break cycle between nmethod & method
1207 if (TraceClassUnloading && WizardMode) {
1208 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1209 " unloadable], Method*(" INTPTR_FORMAT
1210 "), cause(" INTPTR_FORMAT ")",
1211 this, (address)_method, (address)cause);
1212 if (!Universe::heap()->is_gc_active())
1213 cause->klass()->print();
1214 }
1215 // Unlink the osr method, so we do not look this up again
1216 if (is_osr_method()) {
1217 invalidate_osr_method();
1218 }
1219 // If _method is already NULL the Method* is about to be unloaded,
1220 // so we don't have to break the cycle. Note that it is possible to
1221 // have the Method* live here, in case we unload the nmethod because
1222 // it is pointing to some oop (other than the Method*) being unloaded.
1223 if (_method != NULL) {
1224 // OSR methods point to the Method*, but the Method* does not
1225 // point back!
1226 if (_method->code() == this) {
1227 _method->clear_code(); // Break a cycle
1228 }
1229 _method = NULL; // Clear the method of this dead nmethod
1230 }
1231 // Make the class unloaded - i.e., change state and notify sweeper
1232 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1233 if (is_in_use()) {
1234 // Transitioning directly from live to unloaded -- so
1235 // we need to force a cache clean-up; remember this
1236 // for later on.
1237 CodeCache::set_needs_cache_clean(true);
1238 }
1239 _state = unloaded;
1240
1241 // Log the unloading.
1242 log_state_change();
1243
1244 // The Method* is gone at this point
1245 assert(_method == NULL, "Tautology");
1246
1247 set_osr_link(NULL);
1248 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1249 NMethodSweeper::report_state_change(this);
1250 }
1251
1252 void nmethod::invalidate_osr_method() {
1253 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1254 // Remove from list of active nmethods
1255 if (method() != NULL)
1256 method()->method_holder()->remove_osr_nmethod(this);
1257 // Set entry as invalid
1258 _entry_bci = InvalidOSREntryBci;
1259 }
1260
1261 void nmethod::log_state_change() const {
1262 if (LogCompilation) {
1263 if (xtty != NULL) {
1264 ttyLocker ttyl; // keep the following output all in one block
1265 if (_state == unloaded) {
1266 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1267 os::current_thread_id());
1268 } else {
1269 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1270 os::current_thread_id(),
1271 (_state == zombie ? " zombie='1'" : ""));
1272 }
1273 log_identity(xtty);
1274 xtty->stamp();
1275 xtty->end_elem();
1276 }
1277 }
1278 if (PrintCompilation && _state != unloaded) {
1279 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1280 }
1281 }
1282
1283 /**
1284 * Common functionality for both make_not_entrant and make_zombie
1285 */
1286 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1287 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1288 assert(!is_zombie(), "should not already be a zombie");
1289
1290 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1291 nmethodLocker nml(this);
1292 methodHandle the_method(method());
1293 No_Safepoint_Verifier nsv;
1294
1295 // during patching, depending on the nmethod state we must notify the GC that
1296 // code has been unloaded, unregistering it. We cannot do this right while
1297 // holding the Patching_lock because we need to use the CodeCache_lock. This
1298 // would be prone to deadlocks.
1299 // This flag is used to remember whether we need to later lock and unregister.
1300 bool nmethod_needs_unregister = false;
1301
1302 {
1303 // invalidate osr nmethod before acquiring the patching lock since
1304 // they both acquire leaf locks and we don't want a deadlock.
1305 // This logic is equivalent to the logic below for patching the
1306 // verified entry point of regular methods.
1307 if (is_osr_method()) {
1308 // this effectively makes the osr nmethod not entrant
1309 invalidate_osr_method();
1310 }
1311
1312 // Enter critical section. Does not block for safepoint.
1313 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1314
1315 if (_state == state) {
1316 // another thread already performed this transition so nothing
1317 // to do, but return false to indicate this.
1318 return false;
1319 }
1320
1321 // The caller can be calling the method statically or through an inline
1322 // cache call.
1323 if (!is_osr_method() && !is_not_entrant()) {
1324 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1325 SharedRuntime::get_handle_wrong_method_stub());
1326 }
1327
1328 if (is_in_use()) {
1329 // It's a true state change, so mark the method as decompiled.
1330 // Do it only for transition from alive.
1331 inc_decompile_count();
1332 }
1333
1334 // If the state is becoming a zombie, signal to unregister the nmethod with
1335 // the heap.
1336 // This nmethod may have already been unloaded during a full GC.
1337 if ((state == zombie) && !is_unloaded()) {
1338 nmethod_needs_unregister = true;
1339 }
1340
1341 // Must happen before state change. Otherwise we have a race condition in
1342 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1343 // transition its state from 'not_entrant' to 'zombie' without having to wait
1344 // for stack scanning.
1345 if (state == not_entrant) {
1346 mark_as_seen_on_stack();
1347 OrderAccess::storestore();
1348 }
1349
1350 // Change state
1351 _state = state;
1352
1353 // Log the transition once
1354 log_state_change();
1355
1356 // Remove nmethod from method.
1357 // We need to check if both the _code and _from_compiled_code_entry_point
1358 // refer to this nmethod because there is a race in setting these two fields
1359 // in Method* as seen in bugid 4947125.
1360 // If the vep() points to the zombie nmethod, the memory for the nmethod
1361 // could be flushed and the compiler and vtable stubs could still call
1362 // through it.
1363 if (method() != NULL && (method()->code() == this ||
1364 method()->from_compiled_entry() == verified_entry_point())) {
1365 HandleMark hm;
1366 method()->clear_code();
1367 }
1368 } // leave critical region under Patching_lock
1369
1370 // When the nmethod becomes zombie it is no longer alive so the
1371 // dependencies must be flushed. nmethods in the not_entrant
1372 // state will be flushed later when the transition to zombie
1373 // happens or they get unloaded.
1374 if (state == zombie) {
1375 {
1376 // Flushing dependecies must be done before any possible
1377 // safepoint can sneak in, otherwise the oops used by the
1378 // dependency logic could have become stale.
1379 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1380 if (nmethod_needs_unregister) {
1381 Universe::heap()->unregister_nmethod(this);
1382 }
1383 flush_dependencies(NULL);
1384 }
1385
1386 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1387 // event and it hasn't already been reported for this nmethod then
1388 // report it now. The event may have been reported earilier if the GC
1389 // marked it for unloading). JvmtiDeferredEventQueue support means
1390 // we no longer go to a safepoint here.
1391 post_compiled_method_unload();
1392
1393 #ifdef ASSERT
1394 // It's no longer safe to access the oops section since zombie
1395 // nmethods aren't scanned for GC.
1396 _oops_are_stale = true;
1397 #endif
1398 // the Method may be reclaimed by class unloading now that the
1399 // nmethod is in zombie state
1400 set_method(NULL);
1401 } else {
1402 assert(state == not_entrant, "other cases may need to be handled differently");
1403 }
1404
1405 if (TraceCreateZombies) {
1406 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1407 }
1408
1409 NMethodSweeper::report_state_change(this);
1410 return true;
1411 }
1412
1413 void nmethod::flush() {
1414 // Note that there are no valid oops in the nmethod anymore.
1415 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1416 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1417
1418 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1419 assert_locked_or_safepoint(CodeCache_lock);
1420
1421 // completely deallocate this method
1422 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1423 if (PrintMethodFlushing) {
1424 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1425 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
1426 }
1427
1428 // We need to deallocate any ExceptionCache data.
1429 // Note that we do not need to grab the nmethod lock for this, it
1430 // better be thread safe if we're disposing of it!
1431 ExceptionCache* ec = exception_cache();
1432 set_exception_cache(NULL);
1433 while(ec != NULL) {
1434 ExceptionCache* next = ec->next();
1435 delete ec;
1436 ec = next;
1437 }
1438
1439 if (on_scavenge_root_list()) {
1440 CodeCache::drop_scavenge_root_nmethod(this);
1441 }
1442
1443 #ifdef SHARK
1444 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1445 #endif // SHARK
1446
1447 ((CodeBlob*)(this))->flush();
1448
1449 CodeCache::free(this);
1450 }
1451
1452
1453 //
1454 // Notify all classes this nmethod is dependent on that it is no
1455 // longer dependent. This should only be called in two situations.
1456 // First, when a nmethod transitions to a zombie all dependents need
1457 // to be clear. Since zombification happens at a safepoint there's no
1458 // synchronization issues. The second place is a little more tricky.
1459 // During phase 1 of mark sweep class unloading may happen and as a
1460 // result some nmethods may get unloaded. In this case the flushing
1461 // of dependencies must happen during phase 1 since after GC any
1462 // dependencies in the unloaded nmethod won't be updated, so
1463 // traversing the dependency information in unsafe. In that case this
1464 // function is called with a non-NULL argument and this function only
1465 // notifies instanceKlasses that are reachable
1466
1467 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1468 assert_locked_or_safepoint(CodeCache_lock);
1469 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1470 "is_alive is non-NULL if and only if we are called during GC");
1471 if (!has_flushed_dependencies()) {
1472 set_has_flushed_dependencies();
1473 for (Dependencies::DepStream deps(this); deps.next(); ) {
1474 Klass* klass = deps.context_type();
1475 if (klass == NULL) continue; // ignore things like evol_method
1476
1477 // During GC the is_alive closure is non-NULL, and is used to
1478 // determine liveness of dependees that need to be updated.
1479 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1480 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1481 }
1482 }
1483 }
1484 }
1485
1486
1487 // If this oop is not live, the nmethod can be unloaded.
1488 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1489 assert(root != NULL, "just checking");
1490 oop obj = *root;
1491 if (obj == NULL || is_alive->do_object_b(obj)) {
1492 return false;
1493 }
1494
1495 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1496 // simply because one of its constant oops has gone dead.
1497 // No actual classes need to be unloaded in order for this to occur.
1498 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1499 make_unloaded(is_alive, obj);
1500 return true;
1501 }
1502
1503 // ------------------------------------------------------------------
1504 // post_compiled_method_load_event
1505 // new method for install_code() path
1506 // Transfer information from compilation to jvmti
1507 void nmethod::post_compiled_method_load_event() {
1508
1509 Method* moop = method();
1510 HOTSPOT_COMPILED_METHOD_LOAD(
1511 (char *) moop->klass_name()->bytes(),
1512 moop->klass_name()->utf8_length(),
1513 (char *) moop->name()->bytes(),
1514 moop->name()->utf8_length(),
1515 (char *) moop->signature()->bytes(),
1516 moop->signature()->utf8_length(),
1517 insts_begin(), insts_size());
1518
1519 if (JvmtiExport::should_post_compiled_method_load() ||
1520 JvmtiExport::should_post_compiled_method_unload()) {
1521 get_and_cache_jmethod_id();
1522 }
1523
1524 if (JvmtiExport::should_post_compiled_method_load()) {
1525 // Let the Service thread (which is a real Java thread) post the event
1526 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1527 JvmtiDeferredEventQueue::enqueue(
1528 JvmtiDeferredEvent::compiled_method_load_event(this));
1529 }
1530 }
1531
1532 jmethodID nmethod::get_and_cache_jmethod_id() {
1533 if (_jmethod_id == NULL) {
1534 // Cache the jmethod_id since it can no longer be looked up once the
1535 // method itself has been marked for unloading.
1536 _jmethod_id = method()->jmethod_id();
1537 }
1538 return _jmethod_id;
1539 }
1540
1541 void nmethod::post_compiled_method_unload() {
1542 if (unload_reported()) {
1543 // During unloading we transition to unloaded and then to zombie
1544 // and the unloading is reported during the first transition.
1545 return;
1546 }
1547
1548 assert(_method != NULL && !is_unloaded(), "just checking");
1549 DTRACE_METHOD_UNLOAD_PROBE(method());
1550
1551 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1552 // post the event. Sometime later this nmethod will be made a zombie
1553 // by the sweeper but the Method* will not be valid at that point.
1554 // If the _jmethod_id is null then no load event was ever requested
1555 // so don't bother posting the unload. The main reason for this is
1556 // that the jmethodID is a weak reference to the Method* so if
1557 // it's being unloaded there's no way to look it up since the weak
1558 // ref will have been cleared.
1559 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1560 assert(!unload_reported(), "already unloaded");
1561 JvmtiDeferredEvent event =
1562 JvmtiDeferredEvent::compiled_method_unload_event(this,
1563 _jmethod_id, insts_begin());
1564 if (SafepointSynchronize::is_at_safepoint()) {
1565 // Don't want to take the queueing lock. Add it as pending and
1566 // it will get enqueued later.
1567 JvmtiDeferredEventQueue::add_pending_event(event);
1568 } else {
1569 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1570 JvmtiDeferredEventQueue::enqueue(event);
1571 }
1572 }
1573
1574 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1575 // any time. As the nmethod is being unloaded now we mark it has
1576 // having the unload event reported - this will ensure that we don't
1577 // attempt to report the event in the unlikely scenario where the
1578 // event is enabled at the time the nmethod is made a zombie.
1579 set_unload_reported();
1580 }
1581
1582 // This is called at the end of the strong tracing/marking phase of a
1583 // GC to unload an nmethod if it contains otherwise unreachable
1584 // oops.
1585
1586 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1587 // Make sure the oop's ready to receive visitors
1588 assert(!is_zombie() && !is_unloaded(),
1589 "should not call follow on zombie or unloaded nmethod");
1590
1591 // If the method is not entrant then a JMP is plastered over the
1592 // first few bytes. If an oop in the old code was there, that oop
1593 // should not get GC'd. Skip the first few bytes of oops on
1594 // not-entrant methods.
1595 address low_boundary = verified_entry_point();
1596 if (is_not_entrant()) {
1597 low_boundary += NativeJump::instruction_size;
1598 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1599 // (See comment above.)
1600 }
1601
1602 // The RedefineClasses() API can cause the class unloading invariant
1603 // to no longer be true. See jvmtiExport.hpp for details.
1604 // Also, leave a debugging breadcrumb in local flag.
1605 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1606 if (a_class_was_redefined) {
1607 // This set of the unloading_occurred flag is done before the
1608 // call to post_compiled_method_unload() so that the unloading
1609 // of this nmethod is reported.
1610 unloading_occurred = true;
1611 }
1612
1613 // Exception cache
1614 ExceptionCache* ec = exception_cache();
1615 while (ec != NULL) {
1616 Klass* ex_klass = ec->exception_type();
1617 ExceptionCache* next_ec = ec->next();
1618 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
1619 remove_from_exception_cache(ec);
1620 }
1621 ec = next_ec;
1622 }
1623
1624 // If class unloading occurred we first iterate over all inline caches and
1625 // clear ICs where the cached oop is referring to an unloaded klass or method.
1626 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1627 // iteration below.
1628 if (unloading_occurred) {
1629 RelocIterator iter(this, low_boundary);
1630 while(iter.next()) {
1631 if (iter.type() == relocInfo::virtual_call_type) {
1632 CompiledIC *ic = CompiledIC_at(iter.reloc());
1633 if (ic->is_icholder_call()) {
1634 // The only exception is compiledICHolder oops which may
1635 // yet be marked below. (We check this further below).
1636 CompiledICHolder* cichk_oop = ic->cached_icholder();
1637 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1638 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1639 continue;
1640 }
1641 } else {
1642 Metadata* ic_oop = ic->cached_metadata();
1643 if (ic_oop != NULL) {
1644 if (ic_oop->is_klass()) {
1645 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1646 continue;
1647 }
1648 } else if (ic_oop->is_method()) {
1649 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1650 continue;
1651 }
1652 } else {
1653 ShouldNotReachHere();
1654 }
1655 }
1656 }
1657 ic->set_to_clean();
1658 }
1659 }
1660 }
1661
1662 // Compiled code
1663 {
1664 RelocIterator iter(this, low_boundary);
1665 while (iter.next()) {
1666 if (iter.type() == relocInfo::oop_type) {
1667 oop_Relocation* r = iter.oop_reloc();
1668 // In this loop, we must only traverse those oops directly embedded in
1669 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1670 assert(1 == (r->oop_is_immediate()) +
1671 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1672 "oop must be found in exactly one place");
1673 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1674 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1675 return;
1676 }
1677 }
1678 }
1679 }
1680 }
1681
1682
1683 // Scopes
1684 for (oop* p = oops_begin(); p < oops_end(); p++) {
1685 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1686 if (can_unload(is_alive, p, unloading_occurred)) {
1687 return;
1688 }
1689 }
1690
1691 // Ensure that all metadata is still alive
1692 verify_metadata_loaders(low_boundary, is_alive);
1693 }
1694
1695 #ifdef ASSERT
1696
1697 class CheckClass : AllStatic {
1698 static BoolObjectClosure* _is_alive;
1699
1700 // Check class_loader is alive for this bit of metadata.
1701 static void check_class(Metadata* md) {
1702 Klass* klass = NULL;
1703 if (md->is_klass()) {
1704 klass = ((Klass*)md);
1705 } else if (md->is_method()) {
1706 klass = ((Method*)md)->method_holder();
1707 } else if (md->is_methodData()) {
1708 klass = ((MethodData*)md)->method()->method_holder();
1709 } else {
1710 md->print();
1711 ShouldNotReachHere();
1712 }
1713 assert(klass->is_loader_alive(_is_alive), "must be alive");
1714 }
1715 public:
1716 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
1717 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
1718 _is_alive = is_alive;
1719 nm->metadata_do(check_class);
1720 }
1721 };
1722
1723 // This is called during a safepoint so can use static data
1724 BoolObjectClosure* CheckClass::_is_alive = NULL;
1725 #endif // ASSERT
1726
1727
1728 // Processing of oop references should have been sufficient to keep
1729 // all strong references alive. Any weak references should have been
1730 // cleared as well. Visit all the metadata and ensure that it's
1731 // really alive.
1732 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
1733 #ifdef ASSERT
1734 RelocIterator iter(this, low_boundary);
1735 while (iter.next()) {
1736 // static_stub_Relocations may have dangling references to
1737 // Method*s so trim them out here. Otherwise it looks like
1738 // compiled code is maintaining a link to dead metadata.
1739 address static_call_addr = NULL;
1740 if (iter.type() == relocInfo::opt_virtual_call_type) {
1741 CompiledIC* cic = CompiledIC_at(iter.reloc());
1742 if (!cic->is_call_to_interpreted()) {
1743 static_call_addr = iter.addr();
1744 }
1745 } else if (iter.type() == relocInfo::static_call_type) {
1746 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
1747 if (!csc->is_call_to_interpreted()) {
1748 static_call_addr = iter.addr();
1749 }
1750 }
1751 if (static_call_addr != NULL) {
1752 RelocIterator sciter(this, low_boundary);
1753 while (sciter.next()) {
1754 if (sciter.type() == relocInfo::static_stub_type &&
1755 sciter.static_stub_reloc()->static_call() == static_call_addr) {
1756 sciter.static_stub_reloc()->clear_inline_cache();
1757 }
1758 }
1759 }
1760 }
1761 // Check that the metadata embedded in the nmethod is alive
1762 CheckClass::do_check_class(is_alive, this);
1763 #endif
1764 }
1765
1766
1767 // Iterate over metadata calling this function. Used by RedefineClasses
1768 void nmethod::metadata_do(void f(Metadata*)) {
1769 address low_boundary = verified_entry_point();
1770 if (is_not_entrant()) {
1771 low_boundary += NativeJump::instruction_size;
1772 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1773 // (See comment above.)
1774 }
1775 {
1776 // Visit all immediate references that are embedded in the instruction stream.
1777 RelocIterator iter(this, low_boundary);
1778 while (iter.next()) {
1779 if (iter.type() == relocInfo::metadata_type ) {
1780 metadata_Relocation* r = iter.metadata_reloc();
1781 // In this lmetadata, we must only follow those metadatas directly embedded in
1782 // the code. Other metadatas (oop_index>0) are seen as part of
1783 // the metadata section below.
1784 assert(1 == (r->metadata_is_immediate()) +
1785 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
1786 "metadata must be found in exactly one place");
1787 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
1788 Metadata* md = r->metadata_value();
1789 f(md);
1790 }
1791 } else if (iter.type() == relocInfo::virtual_call_type) {
1792 // Check compiledIC holders associated with this nmethod
1793 CompiledIC *ic = CompiledIC_at(iter.reloc());
1794 if (ic->is_icholder_call()) {
1795 CompiledICHolder* cichk = ic->cached_icholder();
1796 f(cichk->holder_method());
1797 f(cichk->holder_klass());
1798 } else {
1799 Metadata* ic_oop = ic->cached_metadata();
1800 if (ic_oop != NULL) {
1801 f(ic_oop);
1802 }
1803 }
1804 }
1805 }
1806 }
1807
1808 // Visit the metadata section
1809 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
1810 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
1811 Metadata* md = *p;
1812 f(md);
1813 }
1814
1815 // Call function Method*, not embedded in these other places.
1816 if (_method != NULL) f(_method);
1817 }
1818
1819 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
1820 // make sure the oops ready to receive visitors
1821 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
1822 assert(!is_unloaded(), "should not call follow on unloaded nmethod");
1823
1824 // If the method is not entrant or zombie then a JMP is plastered over the
1825 // first few bytes. If an oop in the old code was there, that oop
1826 // should not get GC'd. Skip the first few bytes of oops on
1827 // not-entrant methods.
1828 address low_boundary = verified_entry_point();
1829 if (is_not_entrant()) {
1830 low_boundary += NativeJump::instruction_size;
1831 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1832 // (See comment above.)
1833 }
1834
1835 RelocIterator iter(this, low_boundary);
1836
1837 while (iter.next()) {
1838 if (iter.type() == relocInfo::oop_type ) {
1839 oop_Relocation* r = iter.oop_reloc();
1840 // In this loop, we must only follow those oops directly embedded in
1841 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1842 assert(1 == (r->oop_is_immediate()) +
1843 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1844 "oop must be found in exactly one place");
1845 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1846 f->do_oop(r->oop_addr());
1847 }
1848 }
1849 }
1850
1851 // Scopes
1852 // This includes oop constants not inlined in the code stream.
1853 for (oop* p = oops_begin(); p < oops_end(); p++) {
1854 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1855 f->do_oop(p);
1856 }
1857 }
1858
1859 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
1860
1861 nmethod* volatile nmethod::_oops_do_mark_nmethods;
1862
1863 // An nmethod is "marked" if its _mark_link is set non-null.
1864 // Even if it is the end of the linked list, it will have a non-null link value,
1865 // as long as it is on the list.
1866 // This code must be MP safe, because it is used from parallel GC passes.
1867 bool nmethod::test_set_oops_do_mark() {
1868 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1869 nmethod* observed_mark_link = _oops_do_mark_link;
1870 if (observed_mark_link == NULL) {
1871 // Claim this nmethod for this thread to mark.
1872 observed_mark_link = (nmethod*)
1873 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1874 if (observed_mark_link == NULL) {
1875
1876 // Atomically append this nmethod (now claimed) to the head of the list:
1877 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1878 for (;;) {
1879 nmethod* required_mark_nmethods = observed_mark_nmethods;
1880 _oops_do_mark_link = required_mark_nmethods;
1881 observed_mark_nmethods = (nmethod*)
1882 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1883 if (observed_mark_nmethods == required_mark_nmethods)
1884 break;
1885 }
1886 // Mark was clear when we first saw this guy.
1887 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
1888 return false;
1889 }
1890 }
1891 // On fall through, another racing thread marked this nmethod before we did.
1892 return true;
1893 }
1894
1895 void nmethod::oops_do_marking_prologue() {
1896 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
1897 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1898 // We use cmpxchg_ptr instead of regular assignment here because the user
1899 // may fork a bunch of threads, and we need them all to see the same state.
1900 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1901 guarantee(observed == NULL, "no races in this sequential code");
1902 }
1903
1904 void nmethod::oops_do_marking_epilogue() {
1905 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1906 nmethod* cur = _oops_do_mark_nmethods;
1907 while (cur != NMETHOD_SENTINEL) {
1908 assert(cur != NULL, "not NULL-terminated");
1909 nmethod* next = cur->_oops_do_mark_link;
1910 cur->_oops_do_mark_link = NULL;
1911 cur->fix_oop_relocations();
1912 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
1913 cur = next;
1914 }
1915 void* required = _oops_do_mark_nmethods;
1916 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1917 guarantee(observed == required, "no races in this sequential code");
1918 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
1919 }
1920
1921 class DetectScavengeRoot: public OopClosure {
1922 bool _detected_scavenge_root;
1923 public:
1924 DetectScavengeRoot() : _detected_scavenge_root(false)
1925 { NOT_PRODUCT(_print_nm = NULL); }
1926 bool detected_scavenge_root() { return _detected_scavenge_root; }
1927 virtual void do_oop(oop* p) {
1928 if ((*p) != NULL && (*p)->is_scavengable()) {
1929 NOT_PRODUCT(maybe_print(p));
1930 _detected_scavenge_root = true;
1931 }
1932 }
1933 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1934
1935 #ifndef PRODUCT
1936 nmethod* _print_nm;
1937 void maybe_print(oop* p) {
1938 if (_print_nm == NULL) return;
1939 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
1940 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
1941 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
1942 (void *)(*p), (intptr_t)p);
1943 (*p)->print();
1944 }
1945 #endif //PRODUCT
1946 };
1947
1948 bool nmethod::detect_scavenge_root_oops() {
1949 DetectScavengeRoot detect_scavenge_root;
1950 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
1951 oops_do(&detect_scavenge_root);
1952 return detect_scavenge_root.detected_scavenge_root();
1953 }
1954
1955 // Method that knows how to preserve outgoing arguments at call. This method must be
1956 // called with a frame corresponding to a Java invoke
1957 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1958 #ifndef SHARK
1959 if (!method()->is_native()) {
1960 SimpleScopeDesc ssd(this, fr.pc());
1961 Bytecode_invoke call(ssd.method(), ssd.bci());
1962 bool has_receiver = call.has_receiver();
1963 bool has_appendix = call.has_appendix();
1964 Symbol* signature = call.signature();
1965 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
1966 }
1967 #endif // !SHARK
1968 }
1969
1970
1971 oop nmethod::embeddedOop_at(u_char* p) {
1972 RelocIterator iter(this, p, p + 1);
1973 while (iter.next())
1974 if (iter.type() == relocInfo::oop_type) {
1975 return iter.oop_reloc()->oop_value();
1976 }
1977 return NULL;
1978 }
1979
1980
1981 inline bool includes(void* p, void* from, void* to) {
1982 return from <= p && p < to;
1983 }
1984
1985
1986 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1987 assert(count >= 2, "must be sentinel values, at least");
1988
1989 #ifdef ASSERT
1990 // must be sorted and unique; we do a binary search in find_pc_desc()
1991 int prev_offset = pcs[0].pc_offset();
1992 assert(prev_offset == PcDesc::lower_offset_limit,
1993 "must start with a sentinel");
1994 for (int i = 1; i < count; i++) {
1995 int this_offset = pcs[i].pc_offset();
1996 assert(this_offset > prev_offset, "offsets must be sorted");
1997 prev_offset = this_offset;
1998 }
1999 assert(prev_offset == PcDesc::upper_offset_limit,
2000 "must end with a sentinel");
2001 #endif //ASSERT
2002
2003 // Search for MethodHandle invokes and tag the nmethod.
2004 for (int i = 0; i < count; i++) {
2005 if (pcs[i].is_method_handle_invoke()) {
2006 set_has_method_handle_invokes(true);
2007 break;
2008 }
2009 }
2010 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2011
2012 int size = count * sizeof(PcDesc);
2013 assert(scopes_pcs_size() >= size, "oob");
2014 memcpy(scopes_pcs_begin(), pcs, size);
2015
2016 // Adjust the final sentinel downward.
2017 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2018 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2019 last_pc->set_pc_offset(content_size() + 1);
2020 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2021 // Fill any rounding gaps with copies of the last record.
2022 last_pc[1] = last_pc[0];
2023 }
2024 // The following assert could fail if sizeof(PcDesc) is not
2025 // an integral multiple of oopSize (the rounding term).
2026 // If it fails, change the logic to always allocate a multiple
2027 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2028 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2029 }
2030
2031 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2032 assert(scopes_data_size() >= size, "oob");
2033 memcpy(scopes_data_begin(), buffer, size);
2034 }
2035
2036
2037 #ifdef ASSERT
2038 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2039 PcDesc* lower = nm->scopes_pcs_begin();
2040 PcDesc* upper = nm->scopes_pcs_end();
2041 lower += 1; // exclude initial sentinel
2042 PcDesc* res = NULL;
2043 for (PcDesc* p = lower; p < upper; p++) {
2044 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2045 if (match_desc(p, pc_offset, approximate)) {
2046 if (res == NULL)
2047 res = p;
2048 else
2049 res = (PcDesc*) badAddress;
2050 }
2051 }
2052 return res;
2053 }
2054 #endif
2055
2056
2057 // Finds a PcDesc with real-pc equal to "pc"
2058 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2059 address base_address = code_begin();
2060 if ((pc < base_address) ||
2061 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2062 return NULL; // PC is wildly out of range
2063 }
2064 int pc_offset = (int) (pc - base_address);
2065
2066 // Check the PcDesc cache if it contains the desired PcDesc
2067 // (This as an almost 100% hit rate.)
2068 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2069 if (res != NULL) {
2070 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2071 return res;
2072 }
2073
2074 // Fallback algorithm: quasi-linear search for the PcDesc
2075 // Find the last pc_offset less than the given offset.
2076 // The successor must be the required match, if there is a match at all.
2077 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2078 PcDesc* lower = scopes_pcs_begin();
2079 PcDesc* upper = scopes_pcs_end();
2080 upper -= 1; // exclude final sentinel
2081 if (lower >= upper) return NULL; // native method; no PcDescs at all
2082
2083 #define assert_LU_OK \
2084 /* invariant on lower..upper during the following search: */ \
2085 assert(lower->pc_offset() < pc_offset, "sanity"); \
2086 assert(upper->pc_offset() >= pc_offset, "sanity")
2087 assert_LU_OK;
2088
2089 // Use the last successful return as a split point.
2090 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2091 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2092 if (mid->pc_offset() < pc_offset) {
2093 lower = mid;
2094 } else {
2095 upper = mid;
2096 }
2097
2098 // Take giant steps at first (4096, then 256, then 16, then 1)
2099 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2100 const int RADIX = (1 << LOG2_RADIX);
2101 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2102 while ((mid = lower + step) < upper) {
2103 assert_LU_OK;
2104 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2105 if (mid->pc_offset() < pc_offset) {
2106 lower = mid;
2107 } else {
2108 upper = mid;
2109 break;
2110 }
2111 }
2112 assert_LU_OK;
2113 }
2114
2115 // Sneak up on the value with a linear search of length ~16.
2116 while (true) {
2117 assert_LU_OK;
2118 mid = lower + 1;
2119 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2120 if (mid->pc_offset() < pc_offset) {
2121 lower = mid;
2122 } else {
2123 upper = mid;
2124 break;
2125 }
2126 }
2127 #undef assert_LU_OK
2128
2129 if (match_desc(upper, pc_offset, approximate)) {
2130 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2131 _pc_desc_cache.add_pc_desc(upper);
2132 return upper;
2133 } else {
2134 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2135 return NULL;
2136 }
2137 }
2138
2139
2140 void nmethod::check_all_dependencies(DepChange& changes) {
2141 // Checked dependencies are allocated into this ResourceMark
2142 ResourceMark rm;
2143
2144 // Turn off dependency tracing while actually testing dependencies.
2145 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
2146
2147 typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
2148 &DependencySignature::equals, 11027> DepTable;
2149
2150 DepTable* table = new DepTable();
2151
2152 // Iterate over live nmethods and check dependencies of all nmethods that are not
2153 // marked for deoptimization. A particular dependency is only checked once.
2154 for(nmethod* nm = CodeCache::alive_nmethod(CodeCache::first()); nm != NULL; nm = CodeCache::alive_nmethod(CodeCache::next(nm))) {
2155 if (!nm->is_marked_for_deoptimization()) {
2156 for (Dependencies::DepStream deps(nm); deps.next(); ) {
2157 // Construct abstraction of a dependency.
2158 DependencySignature* current_sig = new DependencySignature(deps);
2159
2160 // Determine if dependency is already checked. table->put(...) returns
2161 // 'true' if the dependency is added (i.e., was not in the hashtable).
2162 if (table->put(*current_sig, 1)) {
2163 if (deps.check_dependency() != NULL) {
2164 // Dependency checking failed. Print out information about the failed
2165 // dependency and finally fail with an assert. We can fail here, since
2166 // dependency checking is never done in a product build.
2167 changes.print();
2168 nm->print();
2169 nm->print_dependencies();
2170 assert(false, "Should have been marked for deoptimization");
2171 }
2172 }
2173 }
2174 }
2175 }
2176 }
2177
2178 bool nmethod::check_dependency_on(DepChange& changes) {
2179 // What has happened:
2180 // 1) a new class dependee has been added
2181 // 2) dependee and all its super classes have been marked
2182 bool found_check = false; // set true if we are upset
2183 for (Dependencies::DepStream deps(this); deps.next(); ) {
2184 // Evaluate only relevant dependencies.
2185 if (deps.spot_check_dependency_at(changes) != NULL) {
2186 found_check = true;
2187 NOT_DEBUG(break);
2188 }
2189 }
2190 return found_check;
2191 }
2192
2193 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2194 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2195 Array<Method*>* dependee_methods = dependee_ik->methods();
2196 for (Dependencies::DepStream deps(this); deps.next(); ) {
2197 if (deps.type() == Dependencies::evol_method) {
2198 Method* method = deps.method_argument(0);
2199 for (int j = 0; j < dependee_methods->length(); j++) {
2200 if (dependee_methods->at(j) == method) {
2201 // RC_TRACE macro has an embedded ResourceMark
2202 RC_TRACE(0x01000000,
2203 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2204 _method->method_holder()->external_name(),
2205 _method->name()->as_C_string(),
2206 _method->signature()->as_C_string(), compile_id(),
2207 method->method_holder()->external_name(),
2208 method->name()->as_C_string(),
2209 method->signature()->as_C_string()));
2210 if (TraceDependencies || LogCompilation)
2211 deps.log_dependency(dependee);
2212 return true;
2213 }
2214 }
2215 }
2216 }
2217 return false;
2218 }
2219
2220 // Called from mark_for_deoptimization, when dependee is invalidated.
2221 bool nmethod::is_dependent_on_method(Method* dependee) {
2222 for (Dependencies::DepStream deps(this); deps.next(); ) {
2223 if (deps.type() != Dependencies::evol_method)
2224 continue;
2225 Method* method = deps.method_argument(0);
2226 if (method == dependee) return true;
2227 }
2228 return false;
2229 }
2230
2231
2232 bool nmethod::is_patchable_at(address instr_addr) {
2233 assert(insts_contains(instr_addr), "wrong nmethod used");
2234 if (is_zombie()) {
2235 // a zombie may never be patched
2236 return false;
2237 }
2238 return true;
2239 }
2240
2241
2242 address nmethod::continuation_for_implicit_exception(address pc) {
2243 // Exception happened outside inline-cache check code => we are inside
2244 // an active nmethod => use cpc to determine a return address
2245 int exception_offset = pc - code_begin();
2246 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2247 #ifdef ASSERT
2248 if (cont_offset == 0) {
2249 Thread* thread = ThreadLocalStorage::get_thread_slow();
2250 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2251 HandleMark hm(thread);
2252 ResourceMark rm(thread);
2253 CodeBlob* cb = CodeCache::find_blob(pc);
2254 assert(cb != NULL && cb == this, "");
2255 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2256 print();
2257 method()->print_codes();
2258 print_code();
2259 print_pcs();
2260 }
2261 #endif
2262 if (cont_offset == 0) {
2263 // Let the normal error handling report the exception
2264 return NULL;
2265 }
2266 return code_begin() + cont_offset;
2267 }
2268
2269
2270
2271 void nmethod_init() {
2272 // make sure you didn't forget to adjust the filler fields
2273 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2274 }
2275
2276
2277 //-------------------------------------------------------------------------------------------
2278
2279
2280 // QQQ might we make this work from a frame??
2281 nmethodLocker::nmethodLocker(address pc) {
2282 CodeBlob* cb = CodeCache::find_blob(pc);
2283 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2284 _nm = (nmethod*)cb;
2285 lock_nmethod(_nm);
2286 }
2287
2288 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2289 // should pass zombie_ok == true.
2290 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2291 if (nm == NULL) return;
2292 Atomic::inc(&nm->_lock_count);
2293 assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2294 }
2295
2296 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2297 if (nm == NULL) return;
2298 Atomic::dec(&nm->_lock_count);
2299 assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2300 }
2301
2302
2303 // -----------------------------------------------------------------------------
2304 // nmethod::get_deopt_original_pc
2305 //
2306 // Return the original PC for the given PC if:
2307 // (a) the given PC belongs to a nmethod and
2308 // (b) it is a deopt PC
2309 address nmethod::get_deopt_original_pc(const frame* fr) {
2310 if (fr->cb() == NULL) return NULL;
2311
2312 nmethod* nm = fr->cb()->as_nmethod_or_null();
2313 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2314 return nm->get_original_pc(fr);
2315
2316 return NULL;
2317 }
2318
2319
2320 // -----------------------------------------------------------------------------
2321 // MethodHandle
2322
2323 bool nmethod::is_method_handle_return(address return_pc) {
2324 if (!has_method_handle_invokes()) return false;
2325 PcDesc* pd = pc_desc_at(return_pc);
2326 if (pd == NULL)
2327 return false;
2328 return pd->is_method_handle_invoke();
2329 }
2330
2331
2332 // -----------------------------------------------------------------------------
2333 // Verification
2334
2335 class VerifyOopsClosure: public OopClosure {
2336 nmethod* _nm;
2337 bool _ok;
2338 public:
2339 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2340 bool ok() { return _ok; }
2341 virtual void do_oop(oop* p) {
2342 if ((*p) == NULL || (*p)->is_oop()) return;
2343 if (_ok) {
2344 _nm->print_nmethod(true);
2345 _ok = false;
2346 }
2347 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2348 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2349 }
2350 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2351 };
2352
2353 void nmethod::verify() {
2354
2355 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2356 // seems odd.
2357
2358 if( is_zombie() || is_not_entrant() )
2359 return;
2360
2361 // Make sure all the entry points are correctly aligned for patching.
2362 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2363
2364 // assert(method()->is_oop(), "must be valid");
2365
2366 ResourceMark rm;
2367
2368 if (!CodeCache::contains(this)) {
2369 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2370 }
2371
2372 if(is_native_method() )
2373 return;
2374
2375 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2376 if (nm != this) {
2377 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2378 this));
2379 }
2380
2381 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2382 if (! p->verify(this)) {
2383 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2384 }
2385 }
2386
2387 VerifyOopsClosure voc(this);
2388 oops_do(&voc);
2389 assert(voc.ok(), "embedded oops must be OK");
2390 verify_scavenge_root_oops();
2391
2392 verify_scopes();
2393 }
2394
2395
2396 void nmethod::verify_interrupt_point(address call_site) {
2397 // Verify IC only when nmethod installation is finished.
2398 bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed
2399 || !this->is_in_use(); // nmethod is installed, but not in 'in_use' state
2400 if (is_installed) {
2401 Thread *cur = Thread::current();
2402 if (CompiledIC_lock->owner() == cur ||
2403 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2404 SafepointSynchronize::is_at_safepoint())) {
2405 CompiledIC_at(this, call_site);
2406 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2407 } else {
2408 MutexLocker ml_verify (CompiledIC_lock);
2409 CompiledIC_at(this, call_site);
2410 }
2411 }
2412
2413 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2414 assert(pd != NULL, "PcDesc must exist");
2415 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2416 pd->obj_decode_offset(), pd->should_reexecute(),
2417 pd->return_oop());
2418 !sd->is_top(); sd = sd->sender()) {
2419 sd->verify();
2420 }
2421 }
2422
2423 void nmethod::verify_scopes() {
2424 if( !method() ) return; // Runtime stubs have no scope
2425 if (method()->is_native()) return; // Ignore stub methods.
2426 // iterate through all interrupt point
2427 // and verify the debug information is valid.
2428 RelocIterator iter((nmethod*)this);
2429 while (iter.next()) {
2430 address stub = NULL;
2431 switch (iter.type()) {
2432 case relocInfo::virtual_call_type:
2433 verify_interrupt_point(iter.addr());
2434 break;
2435 case relocInfo::opt_virtual_call_type:
2436 stub = iter.opt_virtual_call_reloc()->static_stub();
2437 verify_interrupt_point(iter.addr());
2438 break;
2439 case relocInfo::static_call_type:
2440 stub = iter.static_call_reloc()->static_stub();
2441 //verify_interrupt_point(iter.addr());
2442 break;
2443 case relocInfo::runtime_call_type:
2444 address destination = iter.reloc()->value();
2445 // Right now there is no way to find out which entries support
2446 // an interrupt point. It would be nice if we had this
2447 // information in a table.
2448 break;
2449 }
2450 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2451 }
2452 }
2453
2454
2455 // -----------------------------------------------------------------------------
2456 // Non-product code
2457 #ifndef PRODUCT
2458
2459 class DebugScavengeRoot: public OopClosure {
2460 nmethod* _nm;
2461 bool _ok;
2462 public:
2463 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2464 bool ok() { return _ok; }
2465 virtual void do_oop(oop* p) {
2466 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2467 if (_ok) {
2468 _nm->print_nmethod(true);
2469 _ok = false;
2470 }
2471 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2472 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2473 (*p)->print();
2474 }
2475 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2476 };
2477
2478 void nmethod::verify_scavenge_root_oops() {
2479 if (!on_scavenge_root_list()) {
2480 // Actually look inside, to verify the claim that it's clean.
2481 DebugScavengeRoot debug_scavenge_root(this);
2482 oops_do(&debug_scavenge_root);
2483 if (!debug_scavenge_root.ok())
2484 fatal("found an unadvertised bad scavengable oop in the code cache");
2485 }
2486 assert(scavenge_root_not_marked(), "");
2487 }
2488
2489 #endif // PRODUCT
2490
2491 // Printing operations
2492
2493 void nmethod::print() const {
2494 ResourceMark rm;
2495 ttyLocker ttyl; // keep the following output all in one block
2496
2497 tty->print("Compiled method ");
2498
2499 if (is_compiled_by_c1()) {
2500 tty->print("(c1) ");
2501 } else if (is_compiled_by_c2()) {
2502 tty->print("(c2) ");
2503 } else if (is_compiled_by_shark()) {
2504 tty->print("(shark) ");
2505 } else {
2506 tty->print("(nm) ");
2507 }
2508
2509 print_on(tty, NULL);
2510
2511 if (WizardMode) {
2512 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2513 tty->print(" for method " INTPTR_FORMAT , (address)method());
2514 tty->print(" { ");
2515 if (is_in_use()) tty->print("in_use ");
2516 if (is_not_entrant()) tty->print("not_entrant ");
2517 if (is_zombie()) tty->print("zombie ");
2518 if (is_unloaded()) tty->print("unloaded ");
2519 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2520 tty->print_cr("}:");
2521 }
2522 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2523 (address)this,
2524 (address)this + size(),
2525 size());
2526 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2527 relocation_begin(),
2528 relocation_end(),
2529 relocation_size());
2530 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2531 consts_begin(),
2532 consts_end(),
2533 consts_size());
2534 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2535 insts_begin(),
2536 insts_end(),
2537 insts_size());
2538 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2539 stub_begin(),
2540 stub_end(),
2541 stub_size());
2542 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2543 oops_begin(),
2544 oops_end(),
2545 oops_size());
2546 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2547 metadata_begin(),
2548 metadata_end(),
2549 metadata_size());
2550 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2551 scopes_data_begin(),
2552 scopes_data_end(),
2553 scopes_data_size());
2554 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2555 scopes_pcs_begin(),
2556 scopes_pcs_end(),
2557 scopes_pcs_size());
2558 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2559 dependencies_begin(),
2560 dependencies_end(),
2561 dependencies_size());
2562 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2563 handler_table_begin(),
2564 handler_table_end(),
2565 handler_table_size());
2566 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2567 nul_chk_table_begin(),
2568 nul_chk_table_end(),
2569 nul_chk_table_size());
2570 }
2571
2572 void nmethod::print_code() {
2573 HandleMark hm;
2574 ResourceMark m;
2575 Disassembler::decode(this);
2576 }
2577
2578
2579 #ifndef PRODUCT
2580
2581 void nmethod::print_scopes() {
2582 // Find the first pc desc for all scopes in the code and print it.
2583 ResourceMark rm;
2584 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2585 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2586 continue;
2587
2588 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2589 sd->print_on(tty, p);
2590 }
2591 }
2592
2593 void nmethod::print_dependencies() {
2594 ResourceMark rm;
2595 ttyLocker ttyl; // keep the following output all in one block
2596 tty->print_cr("Dependencies:");
2597 for (Dependencies::DepStream deps(this); deps.next(); ) {
2598 deps.print_dependency();
2599 Klass* ctxk = deps.context_type();
2600 if (ctxk != NULL) {
2601 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2602 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2603 }
2604 }
2605 deps.log_dependency(); // put it into the xml log also
2606 }
2607 }
2608
2609
2610 void nmethod::print_relocations() {
2611 ResourceMark m; // in case methods get printed via the debugger
2612 tty->print_cr("relocations:");
2613 RelocIterator iter(this);
2614 iter.print();
2615 if (UseRelocIndex) {
2616 jint* index_end = (jint*)relocation_end() - 1;
2617 jint index_size = *index_end;
2618 jint* index_start = (jint*)( (address)index_end - index_size );
2619 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2620 if (index_size > 0) {
2621 jint* ip;
2622 for (ip = index_start; ip+2 <= index_end; ip += 2)
2623 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2624 ip[0],
2625 ip[1],
2626 header_end()+ip[0],
2627 relocation_begin()-1+ip[1]);
2628 for (; ip < index_end; ip++)
2629 tty->print_cr(" (%d ?)", ip[0]);
2630 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip);
2631 ip++;
2632 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2633 }
2634 }
2635 }
2636
2637
2638 void nmethod::print_pcs() {
2639 ResourceMark m; // in case methods get printed via debugger
2640 tty->print_cr("pc-bytecode offsets:");
2641 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2642 p->print(this);
2643 }
2644 }
2645
2646 #endif // PRODUCT
2647
2648 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2649 RelocIterator iter(this, begin, end);
2650 bool have_one = false;
2651 while (iter.next()) {
2652 have_one = true;
2653 switch (iter.type()) {
2654 case relocInfo::none: return "no_reloc";
2655 case relocInfo::oop_type: {
2656 stringStream st;
2657 oop_Relocation* r = iter.oop_reloc();
2658 oop obj = r->oop_value();
2659 st.print("oop(");
2660 if (obj == NULL) st.print("NULL");
2661 else obj->print_value_on(&st);
2662 st.print(")");
2663 return st.as_string();
2664 }
2665 case relocInfo::metadata_type: {
2666 stringStream st;
2667 metadata_Relocation* r = iter.metadata_reloc();
2668 Metadata* obj = r->metadata_value();
2669 st.print("metadata(");
2670 if (obj == NULL) st.print("NULL");
2671 else obj->print_value_on(&st);
2672 st.print(")");
2673 return st.as_string();
2674 }
2675 case relocInfo::virtual_call_type: return "virtual_call";
2676 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2677 case relocInfo::static_call_type: return "static_call";
2678 case relocInfo::static_stub_type: return "static_stub";
2679 case relocInfo::runtime_call_type: return "runtime_call";
2680 case relocInfo::external_word_type: return "external_word";
2681 case relocInfo::internal_word_type: return "internal_word";
2682 case relocInfo::section_word_type: return "section_word";
2683 case relocInfo::poll_type: return "poll";
2684 case relocInfo::poll_return_type: return "poll_return";
2685 case relocInfo::type_mask: return "type_bit_mask";
2686 }
2687 }
2688 return have_one ? "other" : NULL;
2689 }
2690
2691 // Return a the last scope in (begin..end]
2692 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2693 PcDesc* p = pc_desc_near(begin+1);
2694 if (p != NULL && p->real_pc(this) <= end) {
2695 return new ScopeDesc(this, p->scope_decode_offset(),
2696 p->obj_decode_offset(), p->should_reexecute(),
2697 p->return_oop());
2698 }
2699 return NULL;
2700 }
2701
2702 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2703 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2704 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2705 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2706 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2707 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2708
2709 if (has_method_handle_invokes())
2710 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
2711
2712 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
2713
2714 if (block_begin == entry_point()) {
2715 methodHandle m = method();
2716 if (m.not_null()) {
2717 stream->print(" # ");
2718 m->print_value_on(stream);
2719 stream->cr();
2720 }
2721 if (m.not_null() && !is_osr_method()) {
2722 ResourceMark rm;
2723 int sizeargs = m->size_of_parameters();
2724 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2725 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2726 {
2727 int sig_index = 0;
2728 if (!m->is_static())
2729 sig_bt[sig_index++] = T_OBJECT; // 'this'
2730 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2731 BasicType t = ss.type();
2732 sig_bt[sig_index++] = t;
2733 if (type2size[t] == 2) {
2734 sig_bt[sig_index++] = T_VOID;
2735 } else {
2736 assert(type2size[t] == 1, "size is 1 or 2");
2737 }
2738 }
2739 assert(sig_index == sizeargs, "");
2740 }
2741 const char* spname = "sp"; // make arch-specific?
2742 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2743 int stack_slot_offset = this->frame_size() * wordSize;
2744 int tab1 = 14, tab2 = 24;
2745 int sig_index = 0;
2746 int arg_index = (m->is_static() ? 0 : -1);
2747 bool did_old_sp = false;
2748 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2749 bool at_this = (arg_index == -1);
2750 bool at_old_sp = false;
2751 BasicType t = (at_this ? T_OBJECT : ss.type());
2752 assert(t == sig_bt[sig_index], "sigs in sync");
2753 if (at_this)
2754 stream->print(" # this: ");
2755 else
2756 stream->print(" # parm%d: ", arg_index);
2757 stream->move_to(tab1);
2758 VMReg fst = regs[sig_index].first();
2759 VMReg snd = regs[sig_index].second();
2760 if (fst->is_reg()) {
2761 stream->print("%s", fst->name());
2762 if (snd->is_valid()) {
2763 stream->print(":%s", snd->name());
2764 }
2765 } else if (fst->is_stack()) {
2766 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2767 if (offset == stack_slot_offset) at_old_sp = true;
2768 stream->print("[%s+0x%x]", spname, offset);
2769 } else {
2770 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2771 }
2772 stream->print(" ");
2773 stream->move_to(tab2);
2774 stream->print("= ");
2775 if (at_this) {
2776 m->method_holder()->print_value_on(stream);
2777 } else {
2778 bool did_name = false;
2779 if (!at_this && ss.is_object()) {
2780 Symbol* name = ss.as_symbol_or_null();
2781 if (name != NULL) {
2782 name->print_value_on(stream);
2783 did_name = true;
2784 }
2785 }
2786 if (!did_name)
2787 stream->print("%s", type2name(t));
2788 }
2789 if (at_old_sp) {
2790 stream->print(" (%s of caller)", spname);
2791 did_old_sp = true;
2792 }
2793 stream->cr();
2794 sig_index += type2size[t];
2795 arg_index += 1;
2796 if (!at_this) ss.next();
2797 }
2798 if (!did_old_sp) {
2799 stream->print(" # ");
2800 stream->move_to(tab1);
2801 stream->print("[%s+0x%x]", spname, stack_slot_offset);
2802 stream->print(" (%s of caller)", spname);
2803 stream->cr();
2804 }
2805 }
2806 }
2807 }
2808
2809 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2810 // First, find an oopmap in (begin, end].
2811 // We use the odd half-closed interval so that oop maps and scope descs
2812 // which are tied to the byte after a call are printed with the call itself.
2813 address base = code_begin();
2814 OopMapSet* oms = oop_maps();
2815 if (oms != NULL) {
2816 for (int i = 0, imax = oms->size(); i < imax; i++) {
2817 OopMap* om = oms->at(i);
2818 address pc = base + om->offset();
2819 if (pc > begin) {
2820 if (pc <= end) {
2821 st->move_to(column);
2822 st->print("; ");
2823 om->print_on(st);
2824 }
2825 break;
2826 }
2827 }
2828 }
2829
2830 // Print any debug info present at this pc.
2831 ScopeDesc* sd = scope_desc_in(begin, end);
2832 if (sd != NULL) {
2833 st->move_to(column);
2834 if (sd->bci() == SynchronizationEntryBCI) {
2835 st->print(";*synchronization entry");
2836 } else {
2837 if (sd->method() == NULL) {
2838 st->print("method is NULL");
2839 } else if (sd->method()->is_native()) {
2840 st->print("method is native");
2841 } else {
2842 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2843 st->print(";*%s", Bytecodes::name(bc));
2844 switch (bc) {
2845 case Bytecodes::_invokevirtual:
2846 case Bytecodes::_invokespecial:
2847 case Bytecodes::_invokestatic:
2848 case Bytecodes::_invokeinterface:
2849 {
2850 Bytecode_invoke invoke(sd->method(), sd->bci());
2851 st->print(" ");
2852 if (invoke.name() != NULL)
2853 invoke.name()->print_symbol_on(st);
2854 else
2855 st->print("<UNKNOWN>");
2856 break;
2857 }
2858 case Bytecodes::_getfield:
2859 case Bytecodes::_putfield:
2860 case Bytecodes::_getstatic:
2861 case Bytecodes::_putstatic:
2862 {
2863 Bytecode_field field(sd->method(), sd->bci());
2864 st->print(" ");
2865 if (field.name() != NULL)
2866 field.name()->print_symbol_on(st);
2867 else
2868 st->print("<UNKNOWN>");
2869 }
2870 }
2871 }
2872 }
2873
2874 // Print all scopes
2875 for (;sd != NULL; sd = sd->sender()) {
2876 st->move_to(column);
2877 st->print("; -");
2878 if (sd->method() == NULL) {
2879 st->print("method is NULL");
2880 } else {
2881 sd->method()->print_short_name(st);
2882 }
2883 int lineno = sd->method()->line_number_from_bci(sd->bci());
2884 if (lineno != -1) {
2885 st->print("@%d (line %d)", sd->bci(), lineno);
2886 } else {
2887 st->print("@%d", sd->bci());
2888 }
2889 st->cr();
2890 }
2891 }
2892
2893 // Print relocation information
2894 const char* str = reloc_string_for(begin, end);
2895 if (str != NULL) {
2896 if (sd != NULL) st->cr();
2897 st->move_to(column);
2898 st->print("; {%s}", str);
2899 }
2900 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2901 if (cont_offset != 0) {
2902 st->move_to(column);
2903 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
2904 }
2905
2906 }
2907
2908 #ifndef PRODUCT
2909
2910 void nmethod::print_value_on(outputStream* st) const {
2911 st->print("nmethod");
2912 print_on(st, NULL);
2913 }
2914
2915 void nmethod::print_calls(outputStream* st) {
2916 RelocIterator iter(this);
2917 while (iter.next()) {
2918 switch (iter.type()) {
2919 case relocInfo::virtual_call_type:
2920 case relocInfo::opt_virtual_call_type: {
2921 VerifyMutexLocker mc(CompiledIC_lock);
2922 CompiledIC_at(iter.reloc())->print();
2923 break;
2924 }
2925 case relocInfo::static_call_type:
2926 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2927 compiledStaticCall_at(iter.reloc())->print();
2928 break;
2929 }
2930 }
2931 }
2932
2933 void nmethod::print_handler_table() {
2934 ExceptionHandlerTable(this).print();
2935 }
2936
2937 void nmethod::print_nul_chk_table() {
2938 ImplicitExceptionTable(this).print(code_begin());
2939 }
2940
2941 void nmethod::print_statistics() {
2942 ttyLocker ttyl;
2943 if (xtty != NULL) xtty->head("statistics type='nmethod'");
2944 nmethod_stats.print_native_nmethod_stats();
2945 nmethod_stats.print_nmethod_stats();
2946 DebugInformationRecorder::print_statistics();
2947 nmethod_stats.print_pc_stats();
2948 Dependencies::print_statistics();
2949 if (xtty != NULL) xtty->tail("statistics");
2950 }
2951
2952 #endif // PRODUCT