1 /*
2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "code/codeCache.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/dependencies.hpp"
29 #include "code/nmethod.hpp"
30 #include "code/scopeDesc.hpp"
31 #include "compiler/abstractCompiler.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/compileLog.hpp"
34 #include "compiler/compilerOracle.hpp"
35 #include "compiler/disassembler.hpp"
36 #include "interpreter/bytecode.hpp"
37 #include "oops/methodData.hpp"
38 #include "prims/jvmtiRedefineClassesTrace.hpp"
39 #include "prims/jvmtiImpl.hpp"
40 #include "runtime/atomic.inline.hpp"
41 #include "runtime/orderAccess.inline.hpp"
42 #include "runtime/sharedRuntime.hpp"
43 #include "runtime/sweeper.hpp"
44 #include "utilities/resourceHash.hpp"
45 #include "utilities/dtrace.hpp"
46 #include "utilities/events.hpp"
47 #include "utilities/xmlstream.hpp"
48 #ifdef SHARK
49 #include "shark/sharkCompiler.hpp"
50 #endif
51
52 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
53
54 unsigned char nmethod::_global_unloading_clock = 0;
55
56 #ifdef DTRACE_ENABLED
57
58 // Only bother with this argument setup if dtrace is available
59
60 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
61 { \
62 Method* m = (method); \
63 if (m != NULL) { \
64 Symbol* klass_name = m->klass_name(); \
65 Symbol* name = m->name(); \
66 Symbol* signature = m->signature(); \
67 HOTSPOT_COMPILED_METHOD_UNLOAD( \
68 (char *) klass_name->bytes(), klass_name->utf8_length(), \
69 (char *) name->bytes(), name->utf8_length(), \
70 (char *) signature->bytes(), signature->utf8_length()); \
71 } \
72 }
73
74 #else // ndef DTRACE_ENABLED
75
76 #define DTRACE_METHOD_UNLOAD_PROBE(method)
77
78 #endif
79
80 bool nmethod::is_compiled_by_c1() const {
81 if (compiler() == NULL) {
82 return false;
83 }
84 return compiler()->is_c1();
85 }
86 bool nmethod::is_compiled_by_c2() const {
87 if (compiler() == NULL) {
88 return false;
89 }
90 return compiler()->is_c2();
91 }
92 bool nmethod::is_compiled_by_shark() const {
93 if (compiler() == NULL) {
94 return false;
95 }
96 return compiler()->is_shark();
97 }
98
99
100
101 //---------------------------------------------------------------------------------
102 // NMethod statistics
103 // They are printed under various flags, including:
104 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
105 // (In the latter two cases, they like other stats are printed to the log only.)
106
107 #ifndef PRODUCT
108 // These variables are put into one block to reduce relocations
109 // and make it simpler to print from the debugger.
110 static
111 struct nmethod_stats_struct {
112 int nmethod_count;
113 int total_size;
114 int relocation_size;
115 int consts_size;
116 int insts_size;
117 int stub_size;
118 int scopes_data_size;
119 int scopes_pcs_size;
120 int dependencies_size;
121 int handler_table_size;
122 int nul_chk_table_size;
123 int oops_size;
124
125 void note_nmethod(nmethod* nm) {
126 nmethod_count += 1;
127 total_size += nm->size();
128 relocation_size += nm->relocation_size();
129 consts_size += nm->consts_size();
130 insts_size += nm->insts_size();
131 stub_size += nm->stub_size();
132 oops_size += nm->oops_size();
133 scopes_data_size += nm->scopes_data_size();
134 scopes_pcs_size += nm->scopes_pcs_size();
135 dependencies_size += nm->dependencies_size();
136 handler_table_size += nm->handler_table_size();
137 nul_chk_table_size += nm->nul_chk_table_size();
138 }
139 void print_nmethod_stats() {
140 if (nmethod_count == 0) return;
141 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
142 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
143 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
144 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
145 if (insts_size != 0) tty->print_cr(" main code = %d", insts_size);
146 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
147 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
148 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
149 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
150 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
151 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
152 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
153 }
154
155 int native_nmethod_count;
156 int native_total_size;
157 int native_relocation_size;
158 int native_insts_size;
159 int native_oops_size;
160 void note_native_nmethod(nmethod* nm) {
161 native_nmethod_count += 1;
162 native_total_size += nm->size();
163 native_relocation_size += nm->relocation_size();
164 native_insts_size += nm->insts_size();
165 native_oops_size += nm->oops_size();
166 }
167 void print_native_nmethod_stats() {
168 if (native_nmethod_count == 0) return;
169 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
170 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
171 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
172 if (native_insts_size != 0) tty->print_cr(" N. main code = %d", native_insts_size);
173 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
174 }
175
176 int pc_desc_resets; // number of resets (= number of caches)
177 int pc_desc_queries; // queries to nmethod::find_pc_desc
178 int pc_desc_approx; // number of those which have approximate true
179 int pc_desc_repeats; // number of _pc_descs[0] hits
180 int pc_desc_hits; // number of LRU cache hits
181 int pc_desc_tests; // total number of PcDesc examinations
182 int pc_desc_searches; // total number of quasi-binary search steps
183 int pc_desc_adds; // number of LUR cache insertions
184
185 void print_pc_stats() {
186 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
187 pc_desc_queries,
188 (double)(pc_desc_tests + pc_desc_searches)
189 / pc_desc_queries);
190 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
191 pc_desc_resets,
192 pc_desc_queries, pc_desc_approx,
193 pc_desc_repeats, pc_desc_hits,
194 pc_desc_tests, pc_desc_searches, pc_desc_adds);
195 }
196 } nmethod_stats;
197 #endif //PRODUCT
198
199
200 //---------------------------------------------------------------------------------
201
202
203 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
204 assert(pc != NULL, "Must be non null");
205 assert(exception.not_null(), "Must be non null");
206 assert(handler != NULL, "Must be non null");
207
208 _count = 0;
209 _exception_type = exception->klass();
210 _next = NULL;
211
212 add_address_and_handler(pc,handler);
213 }
214
215
216 address ExceptionCache::match(Handle exception, address pc) {
217 assert(pc != NULL,"Must be non null");
218 assert(exception.not_null(),"Must be non null");
219 if (exception->klass() == exception_type()) {
220 return (test_address(pc));
221 }
222
223 return NULL;
224 }
225
226
227 bool ExceptionCache::match_exception_with_space(Handle exception) {
228 assert(exception.not_null(),"Must be non null");
229 if (exception->klass() == exception_type() && count() < cache_size) {
230 return true;
231 }
232 return false;
233 }
234
235
236 address ExceptionCache::test_address(address addr) {
237 for (int i=0; i<count(); i++) {
238 if (pc_at(i) == addr) {
239 return handler_at(i);
240 }
241 }
242 return NULL;
243 }
244
245
246 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
247 if (test_address(addr) == handler) return true;
248 if (count() < cache_size) {
249 set_pc_at(count(),addr);
250 set_handler_at(count(), handler);
251 increment_count();
252 return true;
253 }
254 return false;
255 }
256
257
258 // private method for handling exception cache
259 // These methods are private, and used to manipulate the exception cache
260 // directly.
261 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
262 ExceptionCache* ec = exception_cache();
263 while (ec != NULL) {
264 if (ec->match_exception_with_space(exception)) {
265 return ec;
266 }
267 ec = ec->next();
268 }
269 return NULL;
270 }
271
272
273 //-----------------------------------------------------------------------------
274
275
276 // Helper used by both find_pc_desc methods.
277 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
278 NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
279 if (!approximate)
280 return pc->pc_offset() == pc_offset;
281 else
282 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
283 }
284
285 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
286 if (initial_pc_desc == NULL) {
287 _pc_descs[0] = NULL; // native method; no PcDescs at all
288 return;
289 }
290 NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
291 // reset the cache by filling it with benign (non-null) values
292 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
293 for (int i = 0; i < cache_size; i++)
294 _pc_descs[i] = initial_pc_desc;
295 }
296
297 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
298 NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
299 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
300
301 // Note: one might think that caching the most recently
302 // read value separately would be a win, but one would be
303 // wrong. When many threads are updating it, the cache
304 // line it's in would bounce between caches, negating
305 // any benefit.
306
307 // In order to prevent race conditions do not load cache elements
308 // repeatedly, but use a local copy:
309 PcDesc* res;
310
311 // Step one: Check the most recently added value.
312 res = _pc_descs[0];
313 if (res == NULL) return NULL; // native method; no PcDescs at all
314 if (match_desc(res, pc_offset, approximate)) {
315 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
316 return res;
317 }
318
319 // Step two: Check the rest of the LRU cache.
320 for (int i = 1; i < cache_size; ++i) {
321 res = _pc_descs[i];
322 if (res->pc_offset() < 0) break; // optimization: skip empty cache
323 if (match_desc(res, pc_offset, approximate)) {
324 NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
325 return res;
326 }
327 }
328
329 // Report failure.
330 return NULL;
331 }
332
333 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
334 NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
335 // Update the LRU cache by shifting pc_desc forward.
336 for (int i = 0; i < cache_size; i++) {
337 PcDesc* next = _pc_descs[i];
338 _pc_descs[i] = pc_desc;
339 pc_desc = next;
340 }
341 }
342
343 // adjust pcs_size so that it is a multiple of both oopSize and
344 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
345 // of oopSize, then 2*sizeof(PcDesc) is)
346 static int adjust_pcs_size(int pcs_size) {
347 int nsize = round_to(pcs_size, oopSize);
348 if ((nsize % sizeof(PcDesc)) != 0) {
349 nsize = pcs_size + sizeof(PcDesc);
350 }
351 assert((nsize % oopSize) == 0, "correct alignment");
352 return nsize;
353 }
354
355 //-----------------------------------------------------------------------------
356
357
358 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
359 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
360 assert(new_entry != NULL,"Must be non null");
361 assert(new_entry->next() == NULL, "Must be null");
362
363 if (exception_cache() != NULL) {
364 new_entry->set_next(exception_cache());
365 }
366 set_exception_cache(new_entry);
367 }
368
369 void nmethod::clean_exception_cache(BoolObjectClosure* is_alive) {
370 ExceptionCache* prev = NULL;
371 ExceptionCache* curr = exception_cache();
372
373 while (curr != NULL) {
374 ExceptionCache* next = curr->next();
375
376 Klass* ex_klass = curr->exception_type();
377 if (ex_klass != NULL && !ex_klass->is_loader_alive(is_alive)) {
378 if (prev == NULL) {
379 set_exception_cache(next);
380 } else {
381 prev->set_next(next);
382 }
383 delete curr;
384 // prev stays the same.
385 } else {
386 prev = curr;
387 }
388
389 curr = next;
390 }
391 }
392
393 // public method for accessing the exception cache
394 // These are the public access methods.
395 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
396 // We never grab a lock to read the exception cache, so we may
397 // have false negatives. This is okay, as it can only happen during
398 // the first few exception lookups for a given nmethod.
399 ExceptionCache* ec = exception_cache();
400 while (ec != NULL) {
401 address ret_val;
402 if ((ret_val = ec->match(exception,pc)) != NULL) {
403 return ret_val;
404 }
405 ec = ec->next();
406 }
407 return NULL;
408 }
409
410
411 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
412 // There are potential race conditions during exception cache updates, so we
413 // must own the ExceptionCache_lock before doing ANY modifications. Because
414 // we don't lock during reads, it is possible to have several threads attempt
415 // to update the cache with the same data. We need to check for already inserted
416 // copies of the current data before adding it.
417
418 MutexLocker ml(ExceptionCache_lock);
419 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
420
421 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
422 target_entry = new ExceptionCache(exception,pc,handler);
423 add_exception_cache_entry(target_entry);
424 }
425 }
426
427
428 //-------------end of code for ExceptionCache--------------
429
430
431 int nmethod::total_size() const {
432 return
433 consts_size() +
434 insts_size() +
435 stub_size() +
436 scopes_data_size() +
437 scopes_pcs_size() +
438 handler_table_size() +
439 nul_chk_table_size();
440 }
441
442 const char* nmethod::compile_kind() const {
443 if (is_osr_method()) return "osr";
444 if (method() != NULL && is_native_method()) return "c2n";
445 return NULL;
446 }
447
448 // Fill in default values for various flag fields
449 void nmethod::init_defaults() {
450 _state = in_use;
451 _unloading_clock = 0;
452 _marked_for_reclamation = 0;
453 _has_flushed_dependencies = 0;
454 _has_unsafe_access = 0;
455 _has_method_handle_invokes = 0;
456 _lazy_critical_native = 0;
457 _has_wide_vectors = 0;
458 _marked_for_deoptimization = 0;
459 _lock_count = 0;
460 _stack_traversal_mark = 0;
461 _unload_reported = false; // jvmti state
462
463 #ifdef ASSERT
464 _oops_are_stale = false;
465 #endif
466
467 _oops_do_mark_link = NULL;
468 _jmethod_id = NULL;
469 _osr_link = NULL;
470 if (UseG1GC) {
471 _unloading_next = NULL;
472 } else {
473 _scavenge_root_link = NULL;
474 }
475 _scavenge_root_state = 0;
476 _compiler = NULL;
477 #if INCLUDE_RTM_OPT
478 _rtm_state = NoRTM;
479 #endif
480 #ifdef HAVE_DTRACE_H
481 _trap_offset = 0;
482 #endif // def HAVE_DTRACE_H
483 }
484
485 nmethod* nmethod::new_native_nmethod(methodHandle method,
486 int compile_id,
487 CodeBuffer *code_buffer,
488 int vep_offset,
489 int frame_complete,
490 int frame_size,
491 ByteSize basic_lock_owner_sp_offset,
492 ByteSize basic_lock_sp_offset,
493 OopMapSet* oop_maps) {
494 code_buffer->finalize_oop_references(method);
495 // create nmethod
496 nmethod* nm = NULL;
497 {
498 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
499 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
500 CodeOffsets offsets;
501 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
502 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
503 nm = new (native_nmethod_size, CompLevel_none) nmethod(method(), native_nmethod_size,
504 compile_id, &offsets,
505 code_buffer, frame_size,
506 basic_lock_owner_sp_offset,
507 basic_lock_sp_offset, oop_maps);
508 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm));
509 if (PrintAssembly && nm != NULL) {
510 Disassembler::decode(nm);
511 }
512 }
513 // verify nmethod
514 debug_only(if (nm) nm->verify();) // might block
515
516 if (nm != NULL) {
517 nm->log_new_nmethod();
518 }
519
520 return nm;
521 }
522
523 #ifdef HAVE_DTRACE_H
524 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
525 CodeBuffer *code_buffer,
526 int vep_offset,
527 int trap_offset,
528 int frame_complete,
529 int frame_size) {
530 code_buffer->finalize_oop_references(method);
531 // create nmethod
532 nmethod* nm = NULL;
533 {
534 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
535 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
536 CodeOffsets offsets;
537 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
538 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
539 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
540
541 nm = new (nmethod_size, CompLevel_none) nmethod(method(), nmethod_size,
542 &offsets, code_buffer, frame_size);
543
544 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
545 if (PrintAssembly && nm != NULL) {
546 Disassembler::decode(nm);
547 }
548 }
549 // verify nmethod
550 debug_only(if (nm) nm->verify();) // might block
551
552 if (nm != NULL) {
553 nm->log_new_nmethod();
554 }
555
556 return nm;
557 }
558
559 #endif // def HAVE_DTRACE_H
560
561 nmethod* nmethod::new_nmethod(methodHandle method,
562 int compile_id,
563 int entry_bci,
564 CodeOffsets* offsets,
565 int orig_pc_offset,
566 DebugInformationRecorder* debug_info,
567 Dependencies* dependencies,
568 CodeBuffer* code_buffer, int frame_size,
569 OopMapSet* oop_maps,
570 ExceptionHandlerTable* handler_table,
571 ImplicitExceptionTable* nul_chk_table,
572 AbstractCompiler* compiler,
573 int comp_level
574 )
575 {
576 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
577 code_buffer->finalize_oop_references(method);
578 // create nmethod
579 nmethod* nm = NULL;
580 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
581 int nmethod_size =
582 allocation_size(code_buffer, sizeof(nmethod))
583 + adjust_pcs_size(debug_info->pcs_size())
584 + round_to(dependencies->size_in_bytes() , oopSize)
585 + round_to(handler_table->size_in_bytes(), oopSize)
586 + round_to(nul_chk_table->size_in_bytes(), oopSize)
587 + round_to(debug_info->data_size() , oopSize);
588
589 nm = new (nmethod_size, comp_level)
590 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
591 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
592 oop_maps,
593 handler_table,
594 nul_chk_table,
595 compiler,
596 comp_level);
597
598 if (nm != NULL) {
599 // To make dependency checking during class loading fast, record
600 // the nmethod dependencies in the classes it is dependent on.
601 // This allows the dependency checking code to simply walk the
602 // class hierarchy above the loaded class, checking only nmethods
603 // which are dependent on those classes. The slow way is to
604 // check every nmethod for dependencies which makes it linear in
605 // the number of methods compiled. For applications with a lot
606 // classes the slow way is too slow.
607 for (Dependencies::DepStream deps(nm); deps.next(); ) {
608 Klass* klass = deps.context_type();
609 if (klass == NULL) {
610 continue; // ignore things like evol_method
611 }
612
613 // record this nmethod as dependent on this klass
614 InstanceKlass::cast(klass)->add_dependent_nmethod(nm);
615 }
616 NOT_PRODUCT(nmethod_stats.note_nmethod(nm));
617 if (PrintAssembly || CompilerOracle::has_option_string(method, "PrintAssembly")) {
618 Disassembler::decode(nm);
619 }
620 }
621 }
622 // Do verification and logging outside CodeCache_lock.
623 if (nm != NULL) {
624 // Safepoints in nmethod::verify aren't allowed because nm hasn't been installed yet.
625 DEBUG_ONLY(nm->verify();)
626 nm->log_new_nmethod();
627 }
628 return nm;
629 }
630
631
632 // For native wrappers
633 nmethod::nmethod(
634 Method* method,
635 int nmethod_size,
636 int compile_id,
637 CodeOffsets* offsets,
638 CodeBuffer* code_buffer,
639 int frame_size,
640 ByteSize basic_lock_owner_sp_offset,
641 ByteSize basic_lock_sp_offset,
642 OopMapSet* oop_maps )
643 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
644 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
645 _native_receiver_sp_offset(basic_lock_owner_sp_offset),
646 _native_basic_lock_sp_offset(basic_lock_sp_offset)
647 {
648 {
649 debug_only(No_Safepoint_Verifier nsv;)
650 assert_locked_or_safepoint(CodeCache_lock);
651
652 init_defaults();
653 _method = method;
654 _entry_bci = InvocationEntryBci;
655 // We have no exception handler or deopt handler make the
656 // values something that will never match a pc like the nmethod vtable entry
657 _exception_offset = 0;
658 _deoptimize_offset = 0;
659 _deoptimize_mh_offset = 0;
660 _orig_pc_offset = 0;
661
662 _consts_offset = data_offset();
663 _stub_offset = data_offset();
664 _oops_offset = data_offset();
665 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
666 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
667 _scopes_pcs_offset = _scopes_data_offset;
668 _dependencies_offset = _scopes_pcs_offset;
669 _handler_table_offset = _dependencies_offset;
670 _nul_chk_table_offset = _handler_table_offset;
671 _nmethod_end_offset = _nul_chk_table_offset;
672 _compile_id = compile_id;
673 _comp_level = CompLevel_none;
674 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
675 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
676 _osr_entry_point = NULL;
677 _exception_cache = NULL;
678 _pc_desc_cache.reset_to(NULL);
679 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
680
681 code_buffer->copy_values_to(this);
682 if (ScavengeRootsInCode) {
683 if (detect_scavenge_root_oops()) {
684 CodeCache::add_scavenge_root_nmethod(this);
685 }
686 Universe::heap()->register_nmethod(this);
687 }
688 debug_only(verify_scavenge_root_oops());
689 CodeCache::commit(this);
690 }
691
692 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
693 ttyLocker ttyl; // keep the following output all in one block
694 // This output goes directly to the tty, not the compiler log.
695 // To enable tools to match it up with the compilation activity,
696 // be sure to tag this tty output with the compile ID.
697 if (xtty != NULL) {
698 xtty->begin_head("print_native_nmethod");
699 xtty->method(_method);
700 xtty->stamp();
701 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
702 }
703 // print the header part first
704 print();
705 // then print the requested information
706 if (PrintNativeNMethods) {
707 print_code();
708 if (oop_maps != NULL) {
709 oop_maps->print();
710 }
711 }
712 if (PrintRelocations) {
713 print_relocations();
714 }
715 if (xtty != NULL) {
716 xtty->tail("print_native_nmethod");
717 }
718 }
719 }
720
721 // For dtrace wrappers
722 #ifdef HAVE_DTRACE_H
723 nmethod::nmethod(
724 Method* method,
725 int nmethod_size,
726 CodeOffsets* offsets,
727 CodeBuffer* code_buffer,
728 int frame_size)
729 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
730 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
731 _native_receiver_sp_offset(in_ByteSize(-1)),
732 _native_basic_lock_sp_offset(in_ByteSize(-1))
733 {
734 {
735 debug_only(No_Safepoint_Verifier nsv;)
736 assert_locked_or_safepoint(CodeCache_lock);
737
738 init_defaults();
739 _method = method;
740 _entry_bci = InvocationEntryBci;
741 // We have no exception handler or deopt handler make the
742 // values something that will never match a pc like the nmethod vtable entry
743 _exception_offset = 0;
744 _deoptimize_offset = 0;
745 _deoptimize_mh_offset = 0;
746 _unwind_handler_offset = -1;
747 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
748 _orig_pc_offset = 0;
749 _consts_offset = data_offset();
750 _stub_offset = data_offset();
751 _oops_offset = data_offset();
752 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
753 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
754 _scopes_pcs_offset = _scopes_data_offset;
755 _dependencies_offset = _scopes_pcs_offset;
756 _handler_table_offset = _dependencies_offset;
757 _nul_chk_table_offset = _handler_table_offset;
758 _nmethod_end_offset = _nul_chk_table_offset;
759 _compile_id = 0; // default
760 _comp_level = CompLevel_none;
761 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
762 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
763 _osr_entry_point = NULL;
764 _exception_cache = NULL;
765 _pc_desc_cache.reset_to(NULL);
766 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
767
768 code_buffer->copy_values_to(this);
769 if (ScavengeRootsInCode) {
770 if (detect_scavenge_root_oops()) {
771 CodeCache::add_scavenge_root_nmethod(this);
772 }
773 Universe::heap()->register_nmethod(this);
774 }
775 DEBUG_ONLY(verify_scavenge_root_oops();)
776 CodeCache::commit(this);
777 }
778
779 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
780 ttyLocker ttyl; // keep the following output all in one block
781 // This output goes directly to the tty, not the compiler log.
782 // To enable tools to match it up with the compilation activity,
783 // be sure to tag this tty output with the compile ID.
784 if (xtty != NULL) {
785 xtty->begin_head("print_dtrace_nmethod");
786 xtty->method(_method);
787 xtty->stamp();
788 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
789 }
790 // print the header part first
791 print();
792 // then print the requested information
793 if (PrintNMethods) {
794 print_code();
795 }
796 if (PrintRelocations) {
797 print_relocations();
798 }
799 if (xtty != NULL) {
800 xtty->tail("print_dtrace_nmethod");
801 }
802 }
803 }
804 #endif // def HAVE_DTRACE_H
805
806 void* nmethod::operator new(size_t size, int nmethod_size, int comp_level) throw () {
807 return CodeCache::allocate(nmethod_size, CodeCache::get_code_blob_type(comp_level));
808 }
809
810 nmethod::nmethod(
811 Method* method,
812 int nmethod_size,
813 int compile_id,
814 int entry_bci,
815 CodeOffsets* offsets,
816 int orig_pc_offset,
817 DebugInformationRecorder* debug_info,
818 Dependencies* dependencies,
819 CodeBuffer *code_buffer,
820 int frame_size,
821 OopMapSet* oop_maps,
822 ExceptionHandlerTable* handler_table,
823 ImplicitExceptionTable* nul_chk_table,
824 AbstractCompiler* compiler,
825 int comp_level
826 )
827 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
828 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
829 _native_receiver_sp_offset(in_ByteSize(-1)),
830 _native_basic_lock_sp_offset(in_ByteSize(-1))
831 {
832 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
833 {
834 debug_only(No_Safepoint_Verifier nsv;)
835 assert_locked_or_safepoint(CodeCache_lock);
836
837 init_defaults();
838 _method = method;
839 _entry_bci = entry_bci;
840 _compile_id = compile_id;
841 _comp_level = comp_level;
842 _compiler = compiler;
843 _orig_pc_offset = orig_pc_offset;
844 _hotness_counter = NMethodSweeper::hotness_counter_reset_val();
845
846 // Section offsets
847 _consts_offset = content_offset() + code_buffer->total_offset_of(code_buffer->consts());
848 _stub_offset = content_offset() + code_buffer->total_offset_of(code_buffer->stubs());
849
850 // Exception handler and deopt handler are in the stub section
851 assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
852 assert(offsets->value(CodeOffsets::Deopt ) != -1, "must be set");
853 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
854 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
855 if (offsets->value(CodeOffsets::DeoptMH) != -1) {
856 _deoptimize_mh_offset = _stub_offset + offsets->value(CodeOffsets::DeoptMH);
857 } else {
858 _deoptimize_mh_offset = -1;
859 }
860 if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
861 _unwind_handler_offset = code_offset() + offsets->value(CodeOffsets::UnwindHandler);
862 } else {
863 _unwind_handler_offset = -1;
864 }
865
866 _oops_offset = data_offset();
867 _metadata_offset = _oops_offset + round_to(code_buffer->total_oop_size(), oopSize);
868 _scopes_data_offset = _metadata_offset + round_to(code_buffer->total_metadata_size(), wordSize);
869
870 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
871 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
872 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
873 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
874 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
875
876 _entry_point = code_begin() + offsets->value(CodeOffsets::Entry);
877 _verified_entry_point = code_begin() + offsets->value(CodeOffsets::Verified_Entry);
878 _osr_entry_point = code_begin() + offsets->value(CodeOffsets::OSR_Entry);
879 _exception_cache = NULL;
880 _pc_desc_cache.reset_to(scopes_pcs_begin());
881
882 // Copy contents of ScopeDescRecorder to nmethod
883 code_buffer->copy_values_to(this);
884 debug_info->copy_to(this);
885 dependencies->copy_to(this);
886 if (ScavengeRootsInCode) {
887 if (detect_scavenge_root_oops()) {
888 CodeCache::add_scavenge_root_nmethod(this);
889 }
890 Universe::heap()->register_nmethod(this);
891 }
892 debug_only(verify_scavenge_root_oops());
893
894 CodeCache::commit(this);
895
896 // Copy contents of ExceptionHandlerTable to nmethod
897 handler_table->copy_to(this);
898 nul_chk_table->copy_to(this);
899
900 // we use the information of entry points to find out if a method is
901 // static or non static
902 assert(compiler->is_c2() ||
903 _method->is_static() == (entry_point() == _verified_entry_point),
904 " entry points must be same for static methods and vice versa");
905 }
906
907 bool printnmethods = PrintNMethods
908 || CompilerOracle::should_print(_method)
909 || CompilerOracle::has_option_string(_method, "PrintNMethods");
910 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
911 print_nmethod(printnmethods);
912 }
913 }
914
915
916 // Print a short set of xml attributes to identify this nmethod. The
917 // output should be embedded in some other element.
918 void nmethod::log_identity(xmlStream* log) const {
919 log->print(" compile_id='%d'", compile_id());
920 const char* nm_kind = compile_kind();
921 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
922 if (compiler() != NULL) {
923 log->print(" compiler='%s'", compiler()->name());
924 }
925 if (TieredCompilation) {
926 log->print(" level='%d'", comp_level());
927 }
928 }
929
930
931 #define LOG_OFFSET(log, name) \
932 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
933 log->print(" " XSTR(name) "_offset='%d'" , \
934 (intptr_t)name##_begin() - (intptr_t)this)
935
936
937 void nmethod::log_new_nmethod() const {
938 if (LogCompilation && xtty != NULL) {
939 ttyLocker ttyl;
940 HandleMark hm;
941 xtty->begin_elem("nmethod");
942 log_identity(xtty);
943 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
944 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
945
946 LOG_OFFSET(xtty, relocation);
947 LOG_OFFSET(xtty, consts);
948 LOG_OFFSET(xtty, insts);
949 LOG_OFFSET(xtty, stub);
950 LOG_OFFSET(xtty, scopes_data);
951 LOG_OFFSET(xtty, scopes_pcs);
952 LOG_OFFSET(xtty, dependencies);
953 LOG_OFFSET(xtty, handler_table);
954 LOG_OFFSET(xtty, nul_chk_table);
955 LOG_OFFSET(xtty, oops);
956
957 xtty->method(method());
958 xtty->stamp();
959 xtty->end_elem();
960 }
961 }
962
963 #undef LOG_OFFSET
964
965
966 // Print out more verbose output usually for a newly created nmethod.
967 void nmethod::print_on(outputStream* st, const char* msg) const {
968 if (st != NULL) {
969 ttyLocker ttyl;
970 if (WizardMode) {
971 CompileTask::print_compilation(st, this, msg, /*short_form:*/ true);
972 st->print_cr(" (" INTPTR_FORMAT ")", this);
973 } else {
974 CompileTask::print_compilation(st, this, msg, /*short_form:*/ false);
975 }
976 }
977 }
978
979
980 void nmethod::print_nmethod(bool printmethod) {
981 ttyLocker ttyl; // keep the following output all in one block
982 if (xtty != NULL) {
983 xtty->begin_head("print_nmethod");
984 xtty->stamp();
985 xtty->end_head();
986 }
987 // print the header part first
988 print();
989 // then print the requested information
990 if (printmethod) {
991 print_code();
992 print_pcs();
993 if (oop_maps()) {
994 oop_maps()->print();
995 }
996 }
997 if (PrintDebugInfo) {
998 print_scopes();
999 }
1000 if (PrintRelocations) {
1001 print_relocations();
1002 }
1003 if (PrintDependencies) {
1004 print_dependencies();
1005 }
1006 if (PrintExceptionHandlers) {
1007 print_handler_table();
1008 print_nul_chk_table();
1009 }
1010 if (xtty != NULL) {
1011 xtty->tail("print_nmethod");
1012 }
1013 }
1014
1015
1016 // Promote one word from an assembly-time handle to a live embedded oop.
1017 inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
1018 if (handle == NULL ||
1019 // As a special case, IC oops are initialized to 1 or -1.
1020 handle == (jobject) Universe::non_oop_word()) {
1021 (*dest) = (oop) handle;
1022 } else {
1023 (*dest) = JNIHandles::resolve_non_null(handle);
1024 }
1025 }
1026
1027
1028 // Have to have the same name because it's called by a template
1029 void nmethod::copy_values(GrowableArray<jobject>* array) {
1030 int length = array->length();
1031 assert((address)(oops_begin() + length) <= (address)oops_end(), "oops big enough");
1032 oop* dest = oops_begin();
1033 for (int index = 0 ; index < length; index++) {
1034 initialize_immediate_oop(&dest[index], array->at(index));
1035 }
1036
1037 // Now we can fix up all the oops in the code. We need to do this
1038 // in the code because the assembler uses jobjects as placeholders.
1039 // The code and relocations have already been initialized by the
1040 // CodeBlob constructor, so it is valid even at this early point to
1041 // iterate over relocations and patch the code.
1042 fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1043 }
1044
1045 void nmethod::copy_values(GrowableArray<Metadata*>* array) {
1046 int length = array->length();
1047 assert((address)(metadata_begin() + length) <= (address)metadata_end(), "big enough");
1048 Metadata** dest = metadata_begin();
1049 for (int index = 0 ; index < length; index++) {
1050 dest[index] = array->at(index);
1051 }
1052 }
1053
1054 bool nmethod::is_at_poll_return(address pc) {
1055 RelocIterator iter(this, pc, pc+1);
1056 while (iter.next()) {
1057 if (iter.type() == relocInfo::poll_return_type)
1058 return true;
1059 }
1060 return false;
1061 }
1062
1063
1064 bool nmethod::is_at_poll_or_poll_return(address pc) {
1065 RelocIterator iter(this, pc, pc+1);
1066 while (iter.next()) {
1067 relocInfo::relocType t = iter.type();
1068 if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1069 return true;
1070 }
1071 return false;
1072 }
1073
1074
1075 void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1076 // re-patch all oop-bearing instructions, just in case some oops moved
1077 RelocIterator iter(this, begin, end);
1078 while (iter.next()) {
1079 if (iter.type() == relocInfo::oop_type) {
1080 oop_Relocation* reloc = iter.oop_reloc();
1081 if (initialize_immediates && reloc->oop_is_immediate()) {
1082 oop* dest = reloc->oop_addr();
1083 initialize_immediate_oop(dest, (jobject) *dest);
1084 }
1085 // Refresh the oop-related bits of this instruction.
1086 reloc->fix_oop_relocation();
1087 } else if (iter.type() == relocInfo::metadata_type) {
1088 metadata_Relocation* reloc = iter.metadata_reloc();
1089 reloc->fix_metadata_relocation();
1090 }
1091 }
1092 }
1093
1094
1095 void nmethod::verify_oop_relocations() {
1096 // Ensure sure that the code matches the current oop values
1097 RelocIterator iter(this, NULL, NULL);
1098 while (iter.next()) {
1099 if (iter.type() == relocInfo::oop_type) {
1100 oop_Relocation* reloc = iter.oop_reloc();
1101 if (!reloc->oop_is_immediate()) {
1102 reloc->verify_oop_relocation();
1103 }
1104 }
1105 }
1106 }
1107
1108
1109 ScopeDesc* nmethod::scope_desc_at(address pc) {
1110 PcDesc* pd = pc_desc_at(pc);
1111 guarantee(pd != NULL, "scope must be present");
1112 return new ScopeDesc(this, pd->scope_decode_offset(),
1113 pd->obj_decode_offset(), pd->should_reexecute(),
1114 pd->return_oop());
1115 }
1116
1117
1118 void nmethod::clear_inline_caches() {
1119 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1120 if (is_zombie()) {
1121 return;
1122 }
1123
1124 RelocIterator iter(this);
1125 while (iter.next()) {
1126 iter.reloc()->clear_inline_cache();
1127 }
1128 }
1129
1130 // Clear ICStubs of all compiled ICs
1131 void nmethod::clear_ic_stubs() {
1132 assert_locked_or_safepoint(CompiledIC_lock);
1133 RelocIterator iter(this);
1134 while(iter.next()) {
1135 if (iter.type() == relocInfo::virtual_call_type) {
1136 CompiledIC* ic = CompiledIC_at(&iter);
1137 ic->clear_ic_stub();
1138 }
1139 }
1140 }
1141
1142
1143 void nmethod::cleanup_inline_caches() {
1144
1145 assert_locked_or_safepoint(CompiledIC_lock);
1146
1147 // If the method is not entrant or zombie then a JMP is plastered over the
1148 // first few bytes. If an oop in the old code was there, that oop
1149 // should not get GC'd. Skip the first few bytes of oops on
1150 // not-entrant methods.
1151 address low_boundary = verified_entry_point();
1152 if (!is_in_use()) {
1153 low_boundary += NativeJump::instruction_size;
1154 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1155 // This means that the low_boundary is going to be a little too high.
1156 // This shouldn't matter, since oops of non-entrant methods are never used.
1157 // In fact, why are we bothering to look at oops in a non-entrant method??
1158 }
1159
1160 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1161 ResourceMark rm;
1162 RelocIterator iter(this, low_boundary);
1163 while(iter.next()) {
1164 switch(iter.type()) {
1165 case relocInfo::virtual_call_type:
1166 case relocInfo::opt_virtual_call_type: {
1167 CompiledIC *ic = CompiledIC_at(&iter);
1168 // Ok, to lookup references to zombies here
1169 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1170 if( cb != NULL && cb->is_nmethod() ) {
1171 nmethod* nm = (nmethod*)cb;
1172 // Clean inline caches pointing to both zombie and not_entrant methods
1173 if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1174 }
1175 break;
1176 }
1177 case relocInfo::static_call_type: {
1178 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1179 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1180 if( cb != NULL && cb->is_nmethod() ) {
1181 nmethod* nm = (nmethod*)cb;
1182 // Clean inline caches pointing to both zombie and not_entrant methods
1183 if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1184 }
1185 break;
1186 }
1187 }
1188 }
1189 }
1190
1191 void nmethod::verify_clean_inline_caches() {
1192 assert_locked_or_safepoint(CompiledIC_lock);
1193
1194 // If the method is not entrant or zombie then a JMP is plastered over the
1195 // first few bytes. If an oop in the old code was there, that oop
1196 // should not get GC'd. Skip the first few bytes of oops on
1197 // not-entrant methods.
1198 address low_boundary = verified_entry_point();
1199 if (!is_in_use()) {
1200 low_boundary += NativeJump::instruction_size;
1201 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1202 // This means that the low_boundary is going to be a little too high.
1203 // This shouldn't matter, since oops of non-entrant methods are never used.
1204 // In fact, why are we bothering to look at oops in a non-entrant method??
1205 }
1206
1207 ResourceMark rm;
1208 RelocIterator iter(this, low_boundary);
1209 while(iter.next()) {
1210 switch(iter.type()) {
1211 case relocInfo::virtual_call_type:
1212 case relocInfo::opt_virtual_call_type: {
1213 CompiledIC *ic = CompiledIC_at(&iter);
1214 // Ok, to lookup references to zombies here
1215 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1216 if( cb != NULL && cb->is_nmethod() ) {
1217 nmethod* nm = (nmethod*)cb;
1218 // Verify that inline caches pointing to both zombie and not_entrant methods are clean
1219 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1220 assert(ic->is_clean(), "IC should be clean");
1221 }
1222 }
1223 break;
1224 }
1225 case relocInfo::static_call_type: {
1226 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1227 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1228 if( cb != NULL && cb->is_nmethod() ) {
1229 nmethod* nm = (nmethod*)cb;
1230 // Verify that inline caches pointing to both zombie and not_entrant methods are clean
1231 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1232 assert(csc->is_clean(), "IC should be clean");
1233 }
1234 }
1235 break;
1236 }
1237 }
1238 }
1239 }
1240
1241 int nmethod::verify_icholder_relocations() {
1242 int count = 0;
1243
1244 RelocIterator iter(this);
1245 while(iter.next()) {
1246 if (iter.type() == relocInfo::virtual_call_type) {
1247 if (CompiledIC::is_icholder_call_site(iter.virtual_call_reloc())) {
1248 CompiledIC *ic = CompiledIC_at(&iter);
1249 if (TraceCompiledIC) {
1250 tty->print("noticed icholder " INTPTR_FORMAT " ", p2i(ic->cached_icholder()));
1251 ic->print();
1252 }
1253 assert(ic->cached_icholder() != NULL, "must be non-NULL");
1254 count++;
1255 }
1256 }
1257 }
1258
1259 return count;
1260 }
1261
1262 // This is a private interface with the sweeper.
1263 void nmethod::mark_as_seen_on_stack() {
1264 assert(is_alive(), "Must be an alive method");
1265 // Set the traversal mark to ensure that the sweeper does 2
1266 // cleaning passes before moving to zombie.
1267 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1268 }
1269
1270 // Tell if a non-entrant method can be converted to a zombie (i.e.,
1271 // there are no activations on the stack, not in use by the VM,
1272 // and not in use by the ServiceThread)
1273 bool nmethod::can_not_entrant_be_converted() {
1274 assert(is_not_entrant(), "must be a non-entrant method");
1275
1276 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1277 // count can be greater than the stack traversal count before it hits the
1278 // nmethod for the second time.
1279 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1280 !is_locked_by_vm();
1281 }
1282
1283 void nmethod::inc_decompile_count() {
1284 if (!is_compiled_by_c2()) return;
1285 // Could be gated by ProfileTraps, but do not bother...
1286 Method* m = method();
1287 if (m == NULL) return;
1288 MethodData* mdo = m->method_data();
1289 if (mdo == NULL) return;
1290 // There is a benign race here. See comments in methodData.hpp.
1291 mdo->inc_decompile_count();
1292 }
1293
1294 void nmethod::increase_unloading_clock() {
1295 _global_unloading_clock++;
1296 if (_global_unloading_clock == 0) {
1297 // _nmethods are allocated with _unloading_clock == 0,
1298 // so 0 is never used as a clock value.
1299 _global_unloading_clock = 1;
1300 }
1301 }
1302
1303 void nmethod::set_unloading_clock(unsigned char unloading_clock) {
1304 OrderAccess::release_store((volatile jubyte*)&_unloading_clock, unloading_clock);
1305 }
1306
1307 unsigned char nmethod::unloading_clock() {
1308 return (unsigned char)OrderAccess::load_acquire((volatile jubyte*)&_unloading_clock);
1309 }
1310
1311 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1312
1313 post_compiled_method_unload();
1314
1315 // Since this nmethod is being unloaded, make sure that dependencies
1316 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1317 // indicate that this work is being done during a GC.
1318 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1319 assert(is_alive != NULL, "Should be non-NULL");
1320 // A non-NULL is_alive closure indicates that this is being called during GC.
1321 flush_dependencies(is_alive);
1322
1323 // Break cycle between nmethod & method
1324 if (TraceClassUnloading && WizardMode) {
1325 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1326 " unloadable], Method*(" INTPTR_FORMAT
1327 "), cause(" INTPTR_FORMAT ")",
1328 this, (address)_method, (address)cause);
1329 if (!Universe::heap()->is_gc_active())
1330 cause->klass()->print();
1331 }
1332 // Unlink the osr method, so we do not look this up again
1333 if (is_osr_method()) {
1334 invalidate_osr_method();
1335 }
1336 // If _method is already NULL the Method* is about to be unloaded,
1337 // so we don't have to break the cycle. Note that it is possible to
1338 // have the Method* live here, in case we unload the nmethod because
1339 // it is pointing to some oop (other than the Method*) being unloaded.
1340 if (_method != NULL) {
1341 // OSR methods point to the Method*, but the Method* does not
1342 // point back!
1343 if (_method->code() == this) {
1344 _method->clear_code(); // Break a cycle
1345 }
1346 _method = NULL; // Clear the method of this dead nmethod
1347 }
1348 // Make the class unloaded - i.e., change state and notify sweeper
1349 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1350 if (is_in_use()) {
1351 // Transitioning directly from live to unloaded -- so
1352 // we need to force a cache clean-up; remember this
1353 // for later on.
1354 CodeCache::set_needs_cache_clean(true);
1355 }
1356
1357 // Unregister must be done before the state change
1358 Universe::heap()->unregister_nmethod(this);
1359
1360 _state = unloaded;
1361
1362 // Log the unloading.
1363 log_state_change();
1364
1365 // The Method* is gone at this point
1366 assert(_method == NULL, "Tautology");
1367
1368 set_osr_link(NULL);
1369 //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1370 NMethodSweeper::report_state_change(this);
1371 }
1372
1373 void nmethod::invalidate_osr_method() {
1374 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1375 // Remove from list of active nmethods
1376 if (method() != NULL)
1377 method()->method_holder()->remove_osr_nmethod(this);
1378 }
1379
1380 void nmethod::log_state_change() const {
1381 if (LogCompilation) {
1382 if (xtty != NULL) {
1383 ttyLocker ttyl; // keep the following output all in one block
1384 if (_state == unloaded) {
1385 xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1386 os::current_thread_id());
1387 } else {
1388 xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1389 os::current_thread_id(),
1390 (_state == zombie ? " zombie='1'" : ""));
1391 }
1392 log_identity(xtty);
1393 xtty->stamp();
1394 xtty->end_elem();
1395 }
1396 }
1397 if (PrintCompilation && _state != unloaded) {
1398 print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1399 }
1400 }
1401
1402 /**
1403 * Common functionality for both make_not_entrant and make_zombie
1404 */
1405 bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1406 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1407 assert(!is_zombie(), "should not already be a zombie");
1408
1409 // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1410 nmethodLocker nml(this);
1411 methodHandle the_method(method());
1412 No_Safepoint_Verifier nsv;
1413
1414 // during patching, depending on the nmethod state we must notify the GC that
1415 // code has been unloaded, unregistering it. We cannot do this right while
1416 // holding the Patching_lock because we need to use the CodeCache_lock. This
1417 // would be prone to deadlocks.
1418 // This flag is used to remember whether we need to later lock and unregister.
1419 bool nmethod_needs_unregister = false;
1420
1421 {
1422 // invalidate osr nmethod before acquiring the patching lock since
1423 // they both acquire leaf locks and we don't want a deadlock.
1424 // This logic is equivalent to the logic below for patching the
1425 // verified entry point of regular methods.
1426 if (is_osr_method()) {
1427 // this effectively makes the osr nmethod not entrant
1428 invalidate_osr_method();
1429 }
1430
1431 // Enter critical section. Does not block for safepoint.
1432 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1433
1434 if (_state == state) {
1435 // another thread already performed this transition so nothing
1436 // to do, but return false to indicate this.
1437 return false;
1438 }
1439
1440 // The caller can be calling the method statically or through an inline
1441 // cache call.
1442 if (!is_osr_method() && !is_not_entrant()) {
1443 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1444 SharedRuntime::get_handle_wrong_method_stub());
1445 }
1446
1447 if (is_in_use()) {
1448 // It's a true state change, so mark the method as decompiled.
1449 // Do it only for transition from alive.
1450 inc_decompile_count();
1451 }
1452
1453 // If the state is becoming a zombie, signal to unregister the nmethod with
1454 // the heap.
1455 // This nmethod may have already been unloaded during a full GC.
1456 if ((state == zombie) && !is_unloaded()) {
1457 nmethod_needs_unregister = true;
1458 }
1459
1460 // Must happen before state change. Otherwise we have a race condition in
1461 // nmethod::can_not_entrant_be_converted(). I.e., a method can immediately
1462 // transition its state from 'not_entrant' to 'zombie' without having to wait
1463 // for stack scanning.
1464 if (state == not_entrant) {
1465 mark_as_seen_on_stack();
1466 OrderAccess::storestore();
1467 }
1468
1469 // Change state
1470 _state = state;
1471
1472 // Log the transition once
1473 log_state_change();
1474
1475 // Remove nmethod from method.
1476 // We need to check if both the _code and _from_compiled_code_entry_point
1477 // refer to this nmethod because there is a race in setting these two fields
1478 // in Method* as seen in bugid 4947125.
1479 // If the vep() points to the zombie nmethod, the memory for the nmethod
1480 // could be flushed and the compiler and vtable stubs could still call
1481 // through it.
1482 if (method() != NULL && (method()->code() == this ||
1483 method()->from_compiled_entry() == verified_entry_point())) {
1484 HandleMark hm;
1485 method()->clear_code();
1486 }
1487 } // leave critical region under Patching_lock
1488
1489 // When the nmethod becomes zombie it is no longer alive so the
1490 // dependencies must be flushed. nmethods in the not_entrant
1491 // state will be flushed later when the transition to zombie
1492 // happens or they get unloaded.
1493 if (state == zombie) {
1494 {
1495 // Flushing dependecies must be done before any possible
1496 // safepoint can sneak in, otherwise the oops used by the
1497 // dependency logic could have become stale.
1498 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1499 if (nmethod_needs_unregister) {
1500 Universe::heap()->unregister_nmethod(this);
1501 }
1502 flush_dependencies(NULL);
1503 }
1504
1505 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1506 // event and it hasn't already been reported for this nmethod then
1507 // report it now. The event may have been reported earilier if the GC
1508 // marked it for unloading). JvmtiDeferredEventQueue support means
1509 // we no longer go to a safepoint here.
1510 post_compiled_method_unload();
1511
1512 #ifdef ASSERT
1513 // It's no longer safe to access the oops section since zombie
1514 // nmethods aren't scanned for GC.
1515 _oops_are_stale = true;
1516 #endif
1517 // the Method may be reclaimed by class unloading now that the
1518 // nmethod is in zombie state
1519 set_method(NULL);
1520 } else {
1521 assert(state == not_entrant, "other cases may need to be handled differently");
1522 }
1523
1524 if (TraceCreateZombies) {
1525 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1526 }
1527
1528 NMethodSweeper::report_state_change(this);
1529 return true;
1530 }
1531
1532 void nmethod::flush() {
1533 // Note that there are no valid oops in the nmethod anymore.
1534 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1535 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1536
1537 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1538 assert_locked_or_safepoint(CodeCache_lock);
1539
1540 // completely deallocate this method
1541 Events::log(JavaThread::current(), "flushing nmethod " INTPTR_FORMAT, this);
1542 if (PrintMethodFlushing) {
1543 tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1544 _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity(CodeCache::get_code_blob_type(_comp_level))/1024);
1545 }
1546
1547 // We need to deallocate any ExceptionCache data.
1548 // Note that we do not need to grab the nmethod lock for this, it
1549 // better be thread safe if we're disposing of it!
1550 ExceptionCache* ec = exception_cache();
1551 set_exception_cache(NULL);
1552 while(ec != NULL) {
1553 ExceptionCache* next = ec->next();
1554 delete ec;
1555 ec = next;
1556 }
1557
1558 if (on_scavenge_root_list()) {
1559 CodeCache::drop_scavenge_root_nmethod(this);
1560 }
1561
1562 #ifdef SHARK
1563 ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1564 #endif // SHARK
1565
1566 ((CodeBlob*)(this))->flush();
1567
1568 CodeCache::free(this);
1569 }
1570
1571 //
1572 // Notify all classes this nmethod is dependent on that it is no
1573 // longer dependent. This should only be called in two situations.
1574 // First, when a nmethod transitions to a zombie all dependents need
1575 // to be clear. Since zombification happens at a safepoint there's no
1576 // synchronization issues. The second place is a little more tricky.
1577 // During phase 1 of mark sweep class unloading may happen and as a
1578 // result some nmethods may get unloaded. In this case the flushing
1579 // of dependencies must happen during phase 1 since after GC any
1580 // dependencies in the unloaded nmethod won't be updated, so
1581 // traversing the dependency information in unsafe. In that case this
1582 // function is called with a non-NULL argument and this function only
1583 // notifies instanceKlasses that are reachable
1584
1585 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1586 assert_locked_or_safepoint(CodeCache_lock);
1587 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1588 "is_alive is non-NULL if and only if we are called during GC");
1589 if (!has_flushed_dependencies()) {
1590 set_has_flushed_dependencies();
1591 for (Dependencies::DepStream deps(this); deps.next(); ) {
1592 Klass* klass = deps.context_type();
1593 if (klass == NULL) continue; // ignore things like evol_method
1594
1595 // During GC the is_alive closure is non-NULL, and is used to
1596 // determine liveness of dependees that need to be updated.
1597 if (is_alive == NULL || klass->is_loader_alive(is_alive)) {
1598 InstanceKlass::cast(klass)->remove_dependent_nmethod(this);
1599 }
1600 }
1601 }
1602 }
1603
1604
1605 // If this oop is not live, the nmethod can be unloaded.
1606 bool nmethod::can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred) {
1607 assert(root != NULL, "just checking");
1608 oop obj = *root;
1609 if (obj == NULL || is_alive->do_object_b(obj)) {
1610 return false;
1611 }
1612
1613 // If ScavengeRootsInCode is true, an nmethod might be unloaded
1614 // simply because one of its constant oops has gone dead.
1615 // No actual classes need to be unloaded in order for this to occur.
1616 assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1617 make_unloaded(is_alive, obj);
1618 return true;
1619 }
1620
1621 // ------------------------------------------------------------------
1622 // post_compiled_method_load_event
1623 // new method for install_code() path
1624 // Transfer information from compilation to jvmti
1625 void nmethod::post_compiled_method_load_event() {
1626
1627 Method* moop = method();
1628 HOTSPOT_COMPILED_METHOD_LOAD(
1629 (char *) moop->klass_name()->bytes(),
1630 moop->klass_name()->utf8_length(),
1631 (char *) moop->name()->bytes(),
1632 moop->name()->utf8_length(),
1633 (char *) moop->signature()->bytes(),
1634 moop->signature()->utf8_length(),
1635 insts_begin(), insts_size());
1636
1637 if (JvmtiExport::should_post_compiled_method_load() ||
1638 JvmtiExport::should_post_compiled_method_unload()) {
1639 get_and_cache_jmethod_id();
1640 }
1641
1642 if (JvmtiExport::should_post_compiled_method_load()) {
1643 // Let the Service thread (which is a real Java thread) post the event
1644 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1645 JvmtiDeferredEventQueue::enqueue(
1646 JvmtiDeferredEvent::compiled_method_load_event(this));
1647 }
1648 }
1649
1650 jmethodID nmethod::get_and_cache_jmethod_id() {
1651 if (_jmethod_id == NULL) {
1652 // Cache the jmethod_id since it can no longer be looked up once the
1653 // method itself has been marked for unloading.
1654 _jmethod_id = method()->jmethod_id();
1655 }
1656 return _jmethod_id;
1657 }
1658
1659 void nmethod::post_compiled_method_unload() {
1660 if (unload_reported()) {
1661 // During unloading we transition to unloaded and then to zombie
1662 // and the unloading is reported during the first transition.
1663 return;
1664 }
1665
1666 assert(_method != NULL && !is_unloaded(), "just checking");
1667 DTRACE_METHOD_UNLOAD_PROBE(method());
1668
1669 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1670 // post the event. Sometime later this nmethod will be made a zombie
1671 // by the sweeper but the Method* will not be valid at that point.
1672 // If the _jmethod_id is null then no load event was ever requested
1673 // so don't bother posting the unload. The main reason for this is
1674 // that the jmethodID is a weak reference to the Method* so if
1675 // it's being unloaded there's no way to look it up since the weak
1676 // ref will have been cleared.
1677 if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1678 assert(!unload_reported(), "already unloaded");
1679 JvmtiDeferredEvent event =
1680 JvmtiDeferredEvent::compiled_method_unload_event(this,
1681 _jmethod_id, insts_begin());
1682 if (SafepointSynchronize::is_at_safepoint()) {
1683 // Don't want to take the queueing lock. Add it as pending and
1684 // it will get enqueued later.
1685 JvmtiDeferredEventQueue::add_pending_event(event);
1686 } else {
1687 MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1688 JvmtiDeferredEventQueue::enqueue(event);
1689 }
1690 }
1691
1692 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1693 // any time. As the nmethod is being unloaded now we mark it has
1694 // having the unload event reported - this will ensure that we don't
1695 // attempt to report the event in the unlikely scenario where the
1696 // event is enabled at the time the nmethod is made a zombie.
1697 set_unload_reported();
1698 }
1699
1700 void static clean_ic_if_metadata_is_dead(CompiledIC *ic, BoolObjectClosure *is_alive) {
1701 if (ic->is_icholder_call()) {
1702 // The only exception is compiledICHolder oops which may
1703 // yet be marked below. (We check this further below).
1704 CompiledICHolder* cichk_oop = ic->cached_icholder();
1705 if (cichk_oop->holder_method()->method_holder()->is_loader_alive(is_alive) &&
1706 cichk_oop->holder_klass()->is_loader_alive(is_alive)) {
1707 return;
1708 }
1709 } else {
1710 Metadata* ic_oop = ic->cached_metadata();
1711 if (ic_oop != NULL) {
1712 if (ic_oop->is_klass()) {
1713 if (((Klass*)ic_oop)->is_loader_alive(is_alive)) {
1714 return;
1715 }
1716 } else if (ic_oop->is_method()) {
1717 if (((Method*)ic_oop)->method_holder()->is_loader_alive(is_alive)) {
1718 return;
1719 }
1720 } else {
1721 ShouldNotReachHere();
1722 }
1723 }
1724 }
1725
1726 ic->set_to_clean();
1727 }
1728
1729 // This is called at the end of the strong tracing/marking phase of a
1730 // GC to unload an nmethod if it contains otherwise unreachable
1731 // oops.
1732
1733 void nmethod::do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred) {
1734 // Make sure the oop's ready to receive visitors
1735 assert(!is_zombie() && !is_unloaded(),
1736 "should not call follow on zombie or unloaded nmethod");
1737
1738 // If the method is not entrant then a JMP is plastered over the
1739 // first few bytes. If an oop in the old code was there, that oop
1740 // should not get GC'd. Skip the first few bytes of oops on
1741 // not-entrant methods.
1742 address low_boundary = verified_entry_point();
1743 if (is_not_entrant()) {
1744 low_boundary += NativeJump::instruction_size;
1745 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1746 // (See comment above.)
1747 }
1748
1749 // The RedefineClasses() API can cause the class unloading invariant
1750 // to no longer be true. See jvmtiExport.hpp for details.
1751 // Also, leave a debugging breadcrumb in local flag.
1752 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1753 if (a_class_was_redefined) {
1754 // This set of the unloading_occurred flag is done before the
1755 // call to post_compiled_method_unload() so that the unloading
1756 // of this nmethod is reported.
1757 unloading_occurred = true;
1758 }
1759
1760 // Exception cache
1761 clean_exception_cache(is_alive);
1762
1763 // If class unloading occurred we first iterate over all inline caches and
1764 // clear ICs where the cached oop is referring to an unloaded klass or method.
1765 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1766 // iteration below.
1767 if (unloading_occurred) {
1768 RelocIterator iter(this, low_boundary);
1769 while(iter.next()) {
1770 if (iter.type() == relocInfo::virtual_call_type) {
1771 CompiledIC *ic = CompiledIC_at(&iter);
1772 clean_ic_if_metadata_is_dead(ic, is_alive);
1773 }
1774 }
1775 }
1776
1777 // Compiled code
1778 {
1779 RelocIterator iter(this, low_boundary);
1780 while (iter.next()) {
1781 if (iter.type() == relocInfo::oop_type) {
1782 oop_Relocation* r = iter.oop_reloc();
1783 // In this loop, we must only traverse those oops directly embedded in
1784 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1785 assert(1 == (r->oop_is_immediate()) +
1786 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1787 "oop must be found in exactly one place");
1788 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1789 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1790 return;
1791 }
1792 }
1793 }
1794 }
1795 }
1796
1797
1798 // Scopes
1799 for (oop* p = oops_begin(); p < oops_end(); p++) {
1800 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1801 if (can_unload(is_alive, p, unloading_occurred)) {
1802 return;
1803 }
1804 }
1805
1806 // Ensure that all metadata is still alive
1807 verify_metadata_loaders(low_boundary, is_alive);
1808 }
1809
1810 template <class CompiledICorStaticCall>
1811 static bool clean_if_nmethod_is_unloaded(CompiledICorStaticCall *ic, address addr, BoolObjectClosure *is_alive, nmethod* from) {
1812 // Ok, to lookup references to zombies here
1813 CodeBlob *cb = CodeCache::find_blob_unsafe(addr);
1814 if (cb != NULL && cb->is_nmethod()) {
1815 nmethod* nm = (nmethod*)cb;
1816
1817 if (nm->unloading_clock() != nmethod::global_unloading_clock()) {
1818 // The nmethod has not been processed yet.
1819 return true;
1820 }
1821
1822 // Clean inline caches pointing to both zombie and not_entrant methods
1823 if (!nm->is_in_use() || (nm->method()->code() != nm)) {
1824 ic->set_to_clean();
1825 assert(ic->is_clean(), err_msg("nmethod " PTR_FORMAT "not clean %s", from, from->method()->name_and_sig_as_C_string()));
1826 }
1827 }
1828
1829 return false;
1830 }
1831
1832 static bool clean_if_nmethod_is_unloaded(CompiledIC *ic, BoolObjectClosure *is_alive, nmethod* from) {
1833 return clean_if_nmethod_is_unloaded(ic, ic->ic_destination(), is_alive, from);
1834 }
1835
1836 static bool clean_if_nmethod_is_unloaded(CompiledStaticCall *csc, BoolObjectClosure *is_alive, nmethod* from) {
1837 return clean_if_nmethod_is_unloaded(csc, csc->destination(), is_alive, from);
1838 }
1839
1840 bool nmethod::do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred) {
1841 ResourceMark rm;
1842
1843 // Make sure the oop's ready to receive visitors
1844 assert(!is_zombie() && !is_unloaded(),
1845 "should not call follow on zombie or unloaded nmethod");
1846
1847 // If the method is not entrant then a JMP is plastered over the
1848 // first few bytes. If an oop in the old code was there, that oop
1849 // should not get GC'd. Skip the first few bytes of oops on
1850 // not-entrant methods.
1851 address low_boundary = verified_entry_point();
1852 if (is_not_entrant()) {
1853 low_boundary += NativeJump::instruction_size;
1854 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1855 // (See comment above.)
1856 }
1857
1858 // The RedefineClasses() API can cause the class unloading invariant
1859 // to no longer be true. See jvmtiExport.hpp for details.
1860 // Also, leave a debugging breadcrumb in local flag.
1861 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1862 if (a_class_was_redefined) {
1863 // This set of the unloading_occurred flag is done before the
1864 // call to post_compiled_method_unload() so that the unloading
1865 // of this nmethod is reported.
1866 unloading_occurred = true;
1867 }
1868
1869 // Exception cache
1870 clean_exception_cache(is_alive);
1871
1872 bool is_unloaded = false;
1873 bool postponed = false;
1874
1875 RelocIterator iter(this, low_boundary);
1876 while(iter.next()) {
1877
1878 switch (iter.type()) {
1879
1880 case relocInfo::virtual_call_type:
1881 if (unloading_occurred) {
1882 // If class unloading occurred we first iterate over all inline caches and
1883 // clear ICs where the cached oop is referring to an unloaded klass or method.
1884 clean_ic_if_metadata_is_dead(CompiledIC_at(&iter), is_alive);
1885 }
1886
1887 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1888 break;
1889
1890 case relocInfo::opt_virtual_call_type:
1891 postponed |= clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1892 break;
1893
1894 case relocInfo::static_call_type:
1895 postponed |= clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
1896 break;
1897
1898 case relocInfo::oop_type:
1899 if (!is_unloaded) {
1900 // Unload check
1901 oop_Relocation* r = iter.oop_reloc();
1902 // Traverse those oops directly embedded in the code.
1903 // Other oops (oop_index>0) are seen as part of scopes_oops.
1904 assert(1 == (r->oop_is_immediate()) +
1905 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1906 "oop must be found in exactly one place");
1907 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1908 if (can_unload(is_alive, r->oop_addr(), unloading_occurred)) {
1909 is_unloaded = true;
1910 }
1911 }
1912 }
1913 break;
1914
1915 }
1916 }
1917
1918 if (is_unloaded) {
1919 return postponed;
1920 }
1921
1922 // Scopes
1923 for (oop* p = oops_begin(); p < oops_end(); p++) {
1924 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1925 if (can_unload(is_alive, p, unloading_occurred)) {
1926 is_unloaded = true;
1927 break;
1928 }
1929 }
1930
1931 if (is_unloaded) {
1932 return postponed;
1933 }
1934
1935 // Ensure that all metadata is still alive
1936 verify_metadata_loaders(low_boundary, is_alive);
1937
1938 return postponed;
1939 }
1940
1941 void nmethod::do_unloading_parallel_postponed(BoolObjectClosure* is_alive, bool unloading_occurred) {
1942 ResourceMark rm;
1943
1944 // Make sure the oop's ready to receive visitors
1945 assert(!is_zombie(),
1946 "should not call follow on zombie nmethod");
1947
1948 // If the method is not entrant then a JMP is plastered over the
1949 // first few bytes. If an oop in the old code was there, that oop
1950 // should not get GC'd. Skip the first few bytes of oops on
1951 // not-entrant methods.
1952 address low_boundary = verified_entry_point();
1953 if (is_not_entrant()) {
1954 low_boundary += NativeJump::instruction_size;
1955 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1956 // (See comment above.)
1957 }
1958
1959 RelocIterator iter(this, low_boundary);
1960 while(iter.next()) {
1961
1962 switch (iter.type()) {
1963
1964 case relocInfo::virtual_call_type:
1965 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1966 break;
1967
1968 case relocInfo::opt_virtual_call_type:
1969 clean_if_nmethod_is_unloaded(CompiledIC_at(&iter), is_alive, this);
1970 break;
1971
1972 case relocInfo::static_call_type:
1973 clean_if_nmethod_is_unloaded(compiledStaticCall_at(iter.reloc()), is_alive, this);
1974 break;
1975 }
1976 }
1977 }
1978
1979 #ifdef ASSERT
1980
1981 class CheckClass : AllStatic {
1982 static BoolObjectClosure* _is_alive;
1983
1984 // Check class_loader is alive for this bit of metadata.
1985 static void check_class(Metadata* md) {
1986 Klass* klass = NULL;
1987 if (md->is_klass()) {
1988 klass = ((Klass*)md);
1989 } else if (md->is_method()) {
1990 klass = ((Method*)md)->method_holder();
1991 } else if (md->is_methodData()) {
1992 klass = ((MethodData*)md)->method()->method_holder();
1993 } else {
1994 md->print();
1995 ShouldNotReachHere();
1996 }
1997 assert(klass->is_loader_alive(_is_alive), "must be alive");
1998 }
1999 public:
2000 static void do_check_class(BoolObjectClosure* is_alive, nmethod* nm) {
2001 assert(SafepointSynchronize::is_at_safepoint(), "this is only ok at safepoint");
2002 _is_alive = is_alive;
2003 nm->metadata_do(check_class);
2004 }
2005 };
2006
2007 // This is called during a safepoint so can use static data
2008 BoolObjectClosure* CheckClass::_is_alive = NULL;
2009 #endif // ASSERT
2010
2011
2012 // Processing of oop references should have been sufficient to keep
2013 // all strong references alive. Any weak references should have been
2014 // cleared as well. Visit all the metadata and ensure that it's
2015 // really alive.
2016 void nmethod::verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive) {
2017 #ifdef ASSERT
2018 RelocIterator iter(this, low_boundary);
2019 while (iter.next()) {
2020 // static_stub_Relocations may have dangling references to
2021 // Method*s so trim them out here. Otherwise it looks like
2022 // compiled code is maintaining a link to dead metadata.
2023 address static_call_addr = NULL;
2024 if (iter.type() == relocInfo::opt_virtual_call_type) {
2025 CompiledIC* cic = CompiledIC_at(&iter);
2026 if (!cic->is_call_to_interpreted()) {
2027 static_call_addr = iter.addr();
2028 }
2029 } else if (iter.type() == relocInfo::static_call_type) {
2030 CompiledStaticCall* csc = compiledStaticCall_at(iter.reloc());
2031 if (!csc->is_call_to_interpreted()) {
2032 static_call_addr = iter.addr();
2033 }
2034 }
2035 if (static_call_addr != NULL) {
2036 RelocIterator sciter(this, low_boundary);
2037 while (sciter.next()) {
2038 if (sciter.type() == relocInfo::static_stub_type &&
2039 sciter.static_stub_reloc()->static_call() == static_call_addr) {
2040 sciter.static_stub_reloc()->clear_inline_cache();
2041 }
2042 }
2043 }
2044 }
2045 // Check that the metadata embedded in the nmethod is alive
2046 CheckClass::do_check_class(is_alive, this);
2047 #endif
2048 }
2049
2050
2051 // Iterate over metadata calling this function. Used by RedefineClasses
2052 void nmethod::metadata_do(void f(Metadata*)) {
2053 address low_boundary = verified_entry_point();
2054 if (is_not_entrant()) {
2055 low_boundary += NativeJump::instruction_size;
2056 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
2057 // (See comment above.)
2058 }
2059 {
2060 // Visit all immediate references that are embedded in the instruction stream.
2061 RelocIterator iter(this, low_boundary);
2062 while (iter.next()) {
2063 if (iter.type() == relocInfo::metadata_type ) {
2064 metadata_Relocation* r = iter.metadata_reloc();
2065 // In this lmetadata, we must only follow those metadatas directly embedded in
2066 // the code. Other metadatas (oop_index>0) are seen as part of
2067 // the metadata section below.
2068 assert(1 == (r->metadata_is_immediate()) +
2069 (r->metadata_addr() >= metadata_begin() && r->metadata_addr() < metadata_end()),
2070 "metadata must be found in exactly one place");
2071 if (r->metadata_is_immediate() && r->metadata_value() != NULL) {
2072 Metadata* md = r->metadata_value();
2073 if (md != _method) f(md);
2074 }
2075 } else if (iter.type() == relocInfo::virtual_call_type) {
2076 // Check compiledIC holders associated with this nmethod
2077 CompiledIC *ic = CompiledIC_at(&iter);
2078 if (ic->is_icholder_call()) {
2079 CompiledICHolder* cichk = ic->cached_icholder();
2080 f(cichk->holder_method());
2081 f(cichk->holder_klass());
2082 } else {
2083 Metadata* ic_oop = ic->cached_metadata();
2084 if (ic_oop != NULL) {
2085 f(ic_oop);
2086 }
2087 }
2088 }
2089 }
2090 }
2091
2092 // Visit the metadata section
2093 for (Metadata** p = metadata_begin(); p < metadata_end(); p++) {
2094 if (*p == Universe::non_oop_word() || *p == NULL) continue; // skip non-oops
2095 Metadata* md = *p;
2096 f(md);
2097 }
2098
2099 // Call function Method*, not embedded in these other places.
2100 if (_method != NULL) f(_method);
2101 }
2102
2103 void nmethod::oops_do(OopClosure* f, bool allow_zombie) {
2104 // make sure the oops ready to receive visitors
2105 assert(allow_zombie || !is_zombie(), "should not call follow on zombie nmethod");
2106 assert(!is_unloaded(), "should not call follow on unloaded nmethod");
2107
2108 // If the method is not entrant or zombie then a JMP is plastered over the
2109 // first few bytes. If an oop in the old code was there, that oop
2110 // should not get GC'd. Skip the first few bytes of oops on
2111 // not-entrant methods.
2112 address low_boundary = verified_entry_point();
2113 if (is_not_entrant()) {
2114 low_boundary += NativeJump::instruction_size;
2115 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
2116 // (See comment above.)
2117 }
2118
2119 RelocIterator iter(this, low_boundary);
2120
2121 while (iter.next()) {
2122 if (iter.type() == relocInfo::oop_type ) {
2123 oop_Relocation* r = iter.oop_reloc();
2124 // In this loop, we must only follow those oops directly embedded in
2125 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
2126 assert(1 == (r->oop_is_immediate()) +
2127 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
2128 "oop must be found in exactly one place");
2129 if (r->oop_is_immediate() && r->oop_value() != NULL) {
2130 f->do_oop(r->oop_addr());
2131 }
2132 }
2133 }
2134
2135 // Scopes
2136 // This includes oop constants not inlined in the code stream.
2137 for (oop* p = oops_begin(); p < oops_end(); p++) {
2138 if (*p == Universe::non_oop_word()) continue; // skip non-oops
2139 f->do_oop(p);
2140 }
2141 }
2142
2143 #define NMETHOD_SENTINEL ((nmethod*)badAddress)
2144
2145 nmethod* volatile nmethod::_oops_do_mark_nmethods;
2146
2147 // An nmethod is "marked" if its _mark_link is set non-null.
2148 // Even if it is the end of the linked list, it will have a non-null link value,
2149 // as long as it is on the list.
2150 // This code must be MP safe, because it is used from parallel GC passes.
2151 bool nmethod::test_set_oops_do_mark() {
2152 assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
2153 nmethod* observed_mark_link = _oops_do_mark_link;
2154 if (observed_mark_link == NULL) {
2155 // Claim this nmethod for this thread to mark.
2156 observed_mark_link = (nmethod*)
2157 Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
2158 if (observed_mark_link == NULL) {
2159
2160 // Atomically append this nmethod (now claimed) to the head of the list:
2161 nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
2162 for (;;) {
2163 nmethod* required_mark_nmethods = observed_mark_nmethods;
2164 _oops_do_mark_link = required_mark_nmethods;
2165 observed_mark_nmethods = (nmethod*)
2166 Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
2167 if (observed_mark_nmethods == required_mark_nmethods)
2168 break;
2169 }
2170 // Mark was clear when we first saw this guy.
2171 NOT_PRODUCT(if (TraceScavenge) print_on(tty, "oops_do, mark"));
2172 return false;
2173 }
2174 }
2175 // On fall through, another racing thread marked this nmethod before we did.
2176 return true;
2177 }
2178
2179 void nmethod::oops_do_marking_prologue() {
2180 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("[oops_do_marking_prologue"));
2181 assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
2182 // We use cmpxchg_ptr instead of regular assignment here because the user
2183 // may fork a bunch of threads, and we need them all to see the same state.
2184 void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
2185 guarantee(observed == NULL, "no races in this sequential code");
2186 }
2187
2188 void nmethod::oops_do_marking_epilogue() {
2189 assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
2190 nmethod* cur = _oops_do_mark_nmethods;
2191 while (cur != NMETHOD_SENTINEL) {
2192 assert(cur != NULL, "not NULL-terminated");
2193 nmethod* next = cur->_oops_do_mark_link;
2194 cur->_oops_do_mark_link = NULL;
2195 cur->verify_oop_relocations();
2196 NOT_PRODUCT(if (TraceScavenge) cur->print_on(tty, "oops_do, unmark"));
2197 cur = next;
2198 }
2199 void* required = _oops_do_mark_nmethods;
2200 void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
2201 guarantee(observed == required, "no races in this sequential code");
2202 NOT_PRODUCT(if (TraceScavenge) tty->print_cr("oops_do_marking_epilogue]"));
2203 }
2204
2205 class DetectScavengeRoot: public OopClosure {
2206 bool _detected_scavenge_root;
2207 public:
2208 DetectScavengeRoot() : _detected_scavenge_root(false)
2209 { NOT_PRODUCT(_print_nm = NULL); }
2210 bool detected_scavenge_root() { return _detected_scavenge_root; }
2211 virtual void do_oop(oop* p) {
2212 if ((*p) != NULL && (*p)->is_scavengable()) {
2213 NOT_PRODUCT(maybe_print(p));
2214 _detected_scavenge_root = true;
2215 }
2216 }
2217 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2218
2219 #ifndef PRODUCT
2220 nmethod* _print_nm;
2221 void maybe_print(oop* p) {
2222 if (_print_nm == NULL) return;
2223 if (!_detected_scavenge_root) _print_nm->print_on(tty, "new scavenge root");
2224 tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
2225 _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
2226 (void *)(*p), (intptr_t)p);
2227 (*p)->print();
2228 }
2229 #endif //PRODUCT
2230 };
2231
2232 bool nmethod::detect_scavenge_root_oops() {
2233 DetectScavengeRoot detect_scavenge_root;
2234 NOT_PRODUCT(if (TraceScavenge) detect_scavenge_root._print_nm = this);
2235 oops_do(&detect_scavenge_root);
2236 return detect_scavenge_root.detected_scavenge_root();
2237 }
2238
2239 // Method that knows how to preserve outgoing arguments at call. This method must be
2240 // called with a frame corresponding to a Java invoke
2241 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
2242 #ifndef SHARK
2243 if (!method()->is_native()) {
2244 SimpleScopeDesc ssd(this, fr.pc());
2245 Bytecode_invoke call(ssd.method(), ssd.bci());
2246 bool has_receiver = call.has_receiver();
2247 bool has_appendix = call.has_appendix();
2248 Symbol* signature = call.signature();
2249 fr.oops_compiled_arguments_do(signature, has_receiver, has_appendix, reg_map, f);
2250 }
2251 #endif // !SHARK
2252 }
2253
2254
2255 oop nmethod::embeddedOop_at(u_char* p) {
2256 RelocIterator iter(this, p, p + 1);
2257 while (iter.next())
2258 if (iter.type() == relocInfo::oop_type) {
2259 return iter.oop_reloc()->oop_value();
2260 }
2261 return NULL;
2262 }
2263
2264
2265 inline bool includes(void* p, void* from, void* to) {
2266 return from <= p && p < to;
2267 }
2268
2269
2270 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
2271 assert(count >= 2, "must be sentinel values, at least");
2272
2273 #ifdef ASSERT
2274 // must be sorted and unique; we do a binary search in find_pc_desc()
2275 int prev_offset = pcs[0].pc_offset();
2276 assert(prev_offset == PcDesc::lower_offset_limit,
2277 "must start with a sentinel");
2278 for (int i = 1; i < count; i++) {
2279 int this_offset = pcs[i].pc_offset();
2280 assert(this_offset > prev_offset, "offsets must be sorted");
2281 prev_offset = this_offset;
2282 }
2283 assert(prev_offset == PcDesc::upper_offset_limit,
2284 "must end with a sentinel");
2285 #endif //ASSERT
2286
2287 // Search for MethodHandle invokes and tag the nmethod.
2288 for (int i = 0; i < count; i++) {
2289 if (pcs[i].is_method_handle_invoke()) {
2290 set_has_method_handle_invokes(true);
2291 break;
2292 }
2293 }
2294 assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
2295
2296 int size = count * sizeof(PcDesc);
2297 assert(scopes_pcs_size() >= size, "oob");
2298 memcpy(scopes_pcs_begin(), pcs, size);
2299
2300 // Adjust the final sentinel downward.
2301 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
2302 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
2303 last_pc->set_pc_offset(content_size() + 1);
2304 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
2305 // Fill any rounding gaps with copies of the last record.
2306 last_pc[1] = last_pc[0];
2307 }
2308 // The following assert could fail if sizeof(PcDesc) is not
2309 // an integral multiple of oopSize (the rounding term).
2310 // If it fails, change the logic to always allocate a multiple
2311 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
2312 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
2313 }
2314
2315 void nmethod::copy_scopes_data(u_char* buffer, int size) {
2316 assert(scopes_data_size() >= size, "oob");
2317 memcpy(scopes_data_begin(), buffer, size);
2318 }
2319
2320
2321 #ifdef ASSERT
2322 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
2323 PcDesc* lower = nm->scopes_pcs_begin();
2324 PcDesc* upper = nm->scopes_pcs_end();
2325 lower += 1; // exclude initial sentinel
2326 PcDesc* res = NULL;
2327 for (PcDesc* p = lower; p < upper; p++) {
2328 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
2329 if (match_desc(p, pc_offset, approximate)) {
2330 if (res == NULL)
2331 res = p;
2332 else
2333 res = (PcDesc*) badAddress;
2334 }
2335 }
2336 return res;
2337 }
2338 #endif
2339
2340
2341 // Finds a PcDesc with real-pc equal to "pc"
2342 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
2343 address base_address = code_begin();
2344 if ((pc < base_address) ||
2345 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
2346 return NULL; // PC is wildly out of range
2347 }
2348 int pc_offset = (int) (pc - base_address);
2349
2350 // Check the PcDesc cache if it contains the desired PcDesc
2351 // (This as an almost 100% hit rate.)
2352 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
2353 if (res != NULL) {
2354 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
2355 return res;
2356 }
2357
2358 // Fallback algorithm: quasi-linear search for the PcDesc
2359 // Find the last pc_offset less than the given offset.
2360 // The successor must be the required match, if there is a match at all.
2361 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
2362 PcDesc* lower = scopes_pcs_begin();
2363 PcDesc* upper = scopes_pcs_end();
2364 upper -= 1; // exclude final sentinel
2365 if (lower >= upper) return NULL; // native method; no PcDescs at all
2366
2367 #define assert_LU_OK \
2368 /* invariant on lower..upper during the following search: */ \
2369 assert(lower->pc_offset() < pc_offset, "sanity"); \
2370 assert(upper->pc_offset() >= pc_offset, "sanity")
2371 assert_LU_OK;
2372
2373 // Use the last successful return as a split point.
2374 PcDesc* mid = _pc_desc_cache.last_pc_desc();
2375 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2376 if (mid->pc_offset() < pc_offset) {
2377 lower = mid;
2378 } else {
2379 upper = mid;
2380 }
2381
2382 // Take giant steps at first (4096, then 256, then 16, then 1)
2383 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2384 const int RADIX = (1 << LOG2_RADIX);
2385 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2386 while ((mid = lower + step) < upper) {
2387 assert_LU_OK;
2388 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2389 if (mid->pc_offset() < pc_offset) {
2390 lower = mid;
2391 } else {
2392 upper = mid;
2393 break;
2394 }
2395 }
2396 assert_LU_OK;
2397 }
2398
2399 // Sneak up on the value with a linear search of length ~16.
2400 while (true) {
2401 assert_LU_OK;
2402 mid = lower + 1;
2403 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2404 if (mid->pc_offset() < pc_offset) {
2405 lower = mid;
2406 } else {
2407 upper = mid;
2408 break;
2409 }
2410 }
2411 #undef assert_LU_OK
2412
2413 if (match_desc(upper, pc_offset, approximate)) {
2414 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2415 _pc_desc_cache.add_pc_desc(upper);
2416 return upper;
2417 } else {
2418 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2419 return NULL;
2420 }
2421 }
2422
2423
2424 void nmethod::check_all_dependencies(DepChange& changes) {
2425 // Checked dependencies are allocated into this ResourceMark
2426 ResourceMark rm;
2427
2428 // Turn off dependency tracing while actually testing dependencies.
2429 NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
2430
2431 typedef ResourceHashtable<DependencySignature, int, &DependencySignature::hash,
2432 &DependencySignature::equals, 11027> DepTable;
2433
2434 DepTable* table = new DepTable();
2435
2436 // Iterate over live nmethods and check dependencies of all nmethods that are not
2437 // marked for deoptimization. A particular dependency is only checked once.
2438 NMethodIterator iter;
2439 while(iter.next()) {
2440 nmethod* nm = iter.method();
2441 // Only notify for live nmethods
2442 if (nm->is_alive() && !nm->is_marked_for_deoptimization()) {
2443 for (Dependencies::DepStream deps(nm); deps.next(); ) {
2444 // Construct abstraction of a dependency.
2445 DependencySignature* current_sig = new DependencySignature(deps);
2446
2447 // Determine if dependency is already checked. table->put(...) returns
2448 // 'true' if the dependency is added (i.e., was not in the hashtable).
2449 if (table->put(*current_sig, 1)) {
2450 if (deps.check_dependency() != NULL) {
2451 // Dependency checking failed. Print out information about the failed
2452 // dependency and finally fail with an assert. We can fail here, since
2453 // dependency checking is never done in a product build.
2454 changes.print();
2455 nm->print();
2456 nm->print_dependencies();
2457 assert(false, "Should have been marked for deoptimization");
2458 }
2459 }
2460 }
2461 }
2462 }
2463 }
2464
2465 bool nmethod::check_dependency_on(DepChange& changes) {
2466 // What has happened:
2467 // 1) a new class dependee has been added
2468 // 2) dependee and all its super classes have been marked
2469 bool found_check = false; // set true if we are upset
2470 for (Dependencies::DepStream deps(this); deps.next(); ) {
2471 // Evaluate only relevant dependencies.
2472 if (deps.spot_check_dependency_at(changes) != NULL) {
2473 found_check = true;
2474 NOT_DEBUG(break);
2475 }
2476 }
2477 return found_check;
2478 }
2479
2480 bool nmethod::is_evol_dependent_on(Klass* dependee) {
2481 InstanceKlass *dependee_ik = InstanceKlass::cast(dependee);
2482 Array<Method*>* dependee_methods = dependee_ik->methods();
2483 for (Dependencies::DepStream deps(this); deps.next(); ) {
2484 if (deps.type() == Dependencies::evol_method) {
2485 Method* method = deps.method_argument(0);
2486 for (int j = 0; j < dependee_methods->length(); j++) {
2487 if (dependee_methods->at(j) == method) {
2488 // RC_TRACE macro has an embedded ResourceMark
2489 RC_TRACE(0x01000000,
2490 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2491 _method->method_holder()->external_name(),
2492 _method->name()->as_C_string(),
2493 _method->signature()->as_C_string(), compile_id(),
2494 method->method_holder()->external_name(),
2495 method->name()->as_C_string(),
2496 method->signature()->as_C_string()));
2497 if (TraceDependencies || LogCompilation)
2498 deps.log_dependency(dependee);
2499 return true;
2500 }
2501 }
2502 }
2503 }
2504 return false;
2505 }
2506
2507 // Called from mark_for_deoptimization, when dependee is invalidated.
2508 bool nmethod::is_dependent_on_method(Method* dependee) {
2509 for (Dependencies::DepStream deps(this); deps.next(); ) {
2510 if (deps.type() != Dependencies::evol_method)
2511 continue;
2512 Method* method = deps.method_argument(0);
2513 if (method == dependee) return true;
2514 }
2515 return false;
2516 }
2517
2518
2519 bool nmethod::is_patchable_at(address instr_addr) {
2520 assert(insts_contains(instr_addr), "wrong nmethod used");
2521 if (is_zombie()) {
2522 // a zombie may never be patched
2523 return false;
2524 }
2525 return true;
2526 }
2527
2528
2529 address nmethod::continuation_for_implicit_exception(address pc) {
2530 // Exception happened outside inline-cache check code => we are inside
2531 // an active nmethod => use cpc to determine a return address
2532 int exception_offset = pc - code_begin();
2533 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2534 #ifdef ASSERT
2535 if (cont_offset == 0) {
2536 Thread* thread = ThreadLocalStorage::get_thread_slow();
2537 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2538 HandleMark hm(thread);
2539 ResourceMark rm(thread);
2540 CodeBlob* cb = CodeCache::find_blob(pc);
2541 assert(cb != NULL && cb == this, "");
2542 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2543 print();
2544 method()->print_codes();
2545 print_code();
2546 print_pcs();
2547 }
2548 #endif
2549 if (cont_offset == 0) {
2550 // Let the normal error handling report the exception
2551 return NULL;
2552 }
2553 return code_begin() + cont_offset;
2554 }
2555
2556
2557
2558 void nmethod_init() {
2559 // make sure you didn't forget to adjust the filler fields
2560 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2561 }
2562
2563
2564 //-------------------------------------------------------------------------------------------
2565
2566
2567 // QQQ might we make this work from a frame??
2568 nmethodLocker::nmethodLocker(address pc) {
2569 CodeBlob* cb = CodeCache::find_blob(pc);
2570 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2571 _nm = (nmethod*)cb;
2572 lock_nmethod(_nm);
2573 }
2574
2575 // Only JvmtiDeferredEvent::compiled_method_unload_event()
2576 // should pass zombie_ok == true.
2577 void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2578 if (nm == NULL) return;
2579 Atomic::inc(&nm->_lock_count);
2580 assert(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2581 }
2582
2583 void nmethodLocker::unlock_nmethod(nmethod* nm) {
2584 if (nm == NULL) return;
2585 Atomic::dec(&nm->_lock_count);
2586 assert(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2587 }
2588
2589
2590 // -----------------------------------------------------------------------------
2591 // nmethod::get_deopt_original_pc
2592 //
2593 // Return the original PC for the given PC if:
2594 // (a) the given PC belongs to a nmethod and
2595 // (b) it is a deopt PC
2596 address nmethod::get_deopt_original_pc(const frame* fr) {
2597 if (fr->cb() == NULL) return NULL;
2598
2599 nmethod* nm = fr->cb()->as_nmethod_or_null();
2600 if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2601 return nm->get_original_pc(fr);
2602
2603 return NULL;
2604 }
2605
2606
2607 // -----------------------------------------------------------------------------
2608 // MethodHandle
2609
2610 bool nmethod::is_method_handle_return(address return_pc) {
2611 if (!has_method_handle_invokes()) return false;
2612 PcDesc* pd = pc_desc_at(return_pc);
2613 if (pd == NULL)
2614 return false;
2615 return pd->is_method_handle_invoke();
2616 }
2617
2618
2619 // -----------------------------------------------------------------------------
2620 // Verification
2621
2622 class VerifyOopsClosure: public OopClosure {
2623 nmethod* _nm;
2624 bool _ok;
2625 public:
2626 VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2627 bool ok() { return _ok; }
2628 virtual void do_oop(oop* p) {
2629 if ((*p) == NULL || (*p)->is_oop()) return;
2630 if (_ok) {
2631 _nm->print_nmethod(true);
2632 _ok = false;
2633 }
2634 tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2635 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2636 }
2637 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2638 };
2639
2640 void nmethod::verify() {
2641
2642 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2643 // seems odd.
2644
2645 if( is_zombie() || is_not_entrant() )
2646 return;
2647
2648 // Make sure all the entry points are correctly aligned for patching.
2649 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2650
2651 // assert(method()->is_oop(), "must be valid");
2652
2653 ResourceMark rm;
2654
2655 if (!CodeCache::contains(this)) {
2656 fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2657 }
2658
2659 if(is_native_method() )
2660 return;
2661
2662 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2663 if (nm != this) {
2664 fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2665 this));
2666 }
2667
2668 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2669 if (! p->verify(this)) {
2670 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2671 }
2672 }
2673
2674 VerifyOopsClosure voc(this);
2675 oops_do(&voc);
2676 assert(voc.ok(), "embedded oops must be OK");
2677 verify_scavenge_root_oops();
2678
2679 verify_scopes();
2680 }
2681
2682
2683 void nmethod::verify_interrupt_point(address call_site) {
2684 // Verify IC only when nmethod installation is finished.
2685 bool is_installed = (method()->code() == this) // nmethod is in state 'in_use' and installed
2686 || !this->is_in_use(); // nmethod is installed, but not in 'in_use' state
2687 if (is_installed) {
2688 Thread *cur = Thread::current();
2689 if (CompiledIC_lock->owner() == cur ||
2690 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2691 SafepointSynchronize::is_at_safepoint())) {
2692 CompiledIC_at(this, call_site);
2693 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2694 } else {
2695 MutexLocker ml_verify (CompiledIC_lock);
2696 CompiledIC_at(this, call_site);
2697 }
2698 }
2699
2700 PcDesc* pd = pc_desc_at(nativeCall_at(call_site)->return_address());
2701 assert(pd != NULL, "PcDesc must exist");
2702 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2703 pd->obj_decode_offset(), pd->should_reexecute(),
2704 pd->return_oop());
2705 !sd->is_top(); sd = sd->sender()) {
2706 sd->verify();
2707 }
2708 }
2709
2710 void nmethod::verify_scopes() {
2711 if( !method() ) return; // Runtime stubs have no scope
2712 if (method()->is_native()) return; // Ignore stub methods.
2713 // iterate through all interrupt point
2714 // and verify the debug information is valid.
2715 RelocIterator iter((nmethod*)this);
2716 while (iter.next()) {
2717 address stub = NULL;
2718 switch (iter.type()) {
2719 case relocInfo::virtual_call_type:
2720 verify_interrupt_point(iter.addr());
2721 break;
2722 case relocInfo::opt_virtual_call_type:
2723 stub = iter.opt_virtual_call_reloc()->static_stub();
2724 verify_interrupt_point(iter.addr());
2725 break;
2726 case relocInfo::static_call_type:
2727 stub = iter.static_call_reloc()->static_stub();
2728 //verify_interrupt_point(iter.addr());
2729 break;
2730 case relocInfo::runtime_call_type:
2731 address destination = iter.reloc()->value();
2732 // Right now there is no way to find out which entries support
2733 // an interrupt point. It would be nice if we had this
2734 // information in a table.
2735 break;
2736 }
2737 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2738 }
2739 }
2740
2741
2742 // -----------------------------------------------------------------------------
2743 // Non-product code
2744 #ifndef PRODUCT
2745
2746 class DebugScavengeRoot: public OopClosure {
2747 nmethod* _nm;
2748 bool _ok;
2749 public:
2750 DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2751 bool ok() { return _ok; }
2752 virtual void do_oop(oop* p) {
2753 if ((*p) == NULL || !(*p)->is_scavengable()) return;
2754 if (_ok) {
2755 _nm->print_nmethod(true);
2756 _ok = false;
2757 }
2758 tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2759 (void *)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2760 (*p)->print();
2761 }
2762 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2763 };
2764
2765 void nmethod::verify_scavenge_root_oops() {
2766 if (UseG1GC) {
2767 return;
2768 }
2769
2770 if (!on_scavenge_root_list()) {
2771 // Actually look inside, to verify the claim that it's clean.
2772 DebugScavengeRoot debug_scavenge_root(this);
2773 oops_do(&debug_scavenge_root);
2774 if (!debug_scavenge_root.ok())
2775 fatal("found an unadvertised bad scavengable oop in the code cache");
2776 }
2777 assert(scavenge_root_not_marked(), "");
2778 }
2779
2780 #endif // PRODUCT
2781
2782 // Printing operations
2783
2784 void nmethod::print() const {
2785 ResourceMark rm;
2786 ttyLocker ttyl; // keep the following output all in one block
2787
2788 tty->print("Compiled method ");
2789
2790 if (is_compiled_by_c1()) {
2791 tty->print("(c1) ");
2792 } else if (is_compiled_by_c2()) {
2793 tty->print("(c2) ");
2794 } else if (is_compiled_by_shark()) {
2795 tty->print("(shark) ");
2796 } else {
2797 tty->print("(nm) ");
2798 }
2799
2800 print_on(tty, NULL);
2801
2802 if (WizardMode) {
2803 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2804 tty->print(" for method " INTPTR_FORMAT , (address)method());
2805 tty->print(" { ");
2806 if (is_in_use()) tty->print("in_use ");
2807 if (is_not_entrant()) tty->print("not_entrant ");
2808 if (is_zombie()) tty->print("zombie ");
2809 if (is_unloaded()) tty->print("unloaded ");
2810 if (on_scavenge_root_list()) tty->print("scavenge_root ");
2811 tty->print_cr("}:");
2812 }
2813 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2814 (address)this,
2815 (address)this + size(),
2816 size());
2817 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2818 relocation_begin(),
2819 relocation_end(),
2820 relocation_size());
2821 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2822 consts_begin(),
2823 consts_end(),
2824 consts_size());
2825 if (insts_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2826 insts_begin(),
2827 insts_end(),
2828 insts_size());
2829 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2830 stub_begin(),
2831 stub_end(),
2832 stub_size());
2833 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2834 oops_begin(),
2835 oops_end(),
2836 oops_size());
2837 if (metadata_size () > 0) tty->print_cr(" metadata [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2838 metadata_begin(),
2839 metadata_end(),
2840 metadata_size());
2841 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2842 scopes_data_begin(),
2843 scopes_data_end(),
2844 scopes_data_size());
2845 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2846 scopes_pcs_begin(),
2847 scopes_pcs_end(),
2848 scopes_pcs_size());
2849 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2850 dependencies_begin(),
2851 dependencies_end(),
2852 dependencies_size());
2853 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2854 handler_table_begin(),
2855 handler_table_end(),
2856 handler_table_size());
2857 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2858 nul_chk_table_begin(),
2859 nul_chk_table_end(),
2860 nul_chk_table_size());
2861 }
2862
2863 void nmethod::print_code() {
2864 HandleMark hm;
2865 ResourceMark m;
2866 Disassembler::decode(this);
2867 }
2868
2869
2870 #ifndef PRODUCT
2871
2872 void nmethod::print_scopes() {
2873 // Find the first pc desc for all scopes in the code and print it.
2874 ResourceMark rm;
2875 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2876 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2877 continue;
2878
2879 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2880 sd->print_on(tty, p);
2881 }
2882 }
2883
2884 void nmethod::print_dependencies() {
2885 ResourceMark rm;
2886 ttyLocker ttyl; // keep the following output all in one block
2887 tty->print_cr("Dependencies:");
2888 for (Dependencies::DepStream deps(this); deps.next(); ) {
2889 deps.print_dependency();
2890 Klass* ctxk = deps.context_type();
2891 if (ctxk != NULL) {
2892 if (ctxk->oop_is_instance() && ((InstanceKlass*)ctxk)->is_dependent_nmethod(this)) {
2893 tty->print_cr(" [nmethod<=klass]%s", ctxk->external_name());
2894 }
2895 }
2896 deps.log_dependency(); // put it into the xml log also
2897 }
2898 }
2899
2900
2901 void nmethod::print_relocations() {
2902 ResourceMark m; // in case methods get printed via the debugger
2903 tty->print_cr("relocations:");
2904 RelocIterator iter(this);
2905 iter.print();
2906 if (UseRelocIndex) {
2907 jint* index_end = (jint*)relocation_end() - 1;
2908 jint index_size = *index_end;
2909 jint* index_start = (jint*)( (address)index_end - index_size );
2910 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2911 if (index_size > 0) {
2912 jint* ip;
2913 for (ip = index_start; ip+2 <= index_end; ip += 2)
2914 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2915 ip[0],
2916 ip[1],
2917 header_end()+ip[0],
2918 relocation_begin()-1+ip[1]);
2919 for (; ip < index_end; ip++)
2920 tty->print_cr(" (%d ?)", ip[0]);
2921 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip);
2922 ip++;
2923 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2924 }
2925 }
2926 }
2927
2928
2929 void nmethod::print_pcs() {
2930 ResourceMark m; // in case methods get printed via debugger
2931 tty->print_cr("pc-bytecode offsets:");
2932 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2933 p->print(this);
2934 }
2935 }
2936
2937 #endif // PRODUCT
2938
2939 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2940 RelocIterator iter(this, begin, end);
2941 bool have_one = false;
2942 while (iter.next()) {
2943 have_one = true;
2944 switch (iter.type()) {
2945 case relocInfo::none: return "no_reloc";
2946 case relocInfo::oop_type: {
2947 stringStream st;
2948 oop_Relocation* r = iter.oop_reloc();
2949 oop obj = r->oop_value();
2950 st.print("oop(");
2951 if (obj == NULL) st.print("NULL");
2952 else obj->print_value_on(&st);
2953 st.print(")");
2954 return st.as_string();
2955 }
2956 case relocInfo::metadata_type: {
2957 stringStream st;
2958 metadata_Relocation* r = iter.metadata_reloc();
2959 Metadata* obj = r->metadata_value();
2960 st.print("metadata(");
2961 if (obj == NULL) st.print("NULL");
2962 else obj->print_value_on(&st);
2963 st.print(")");
2964 return st.as_string();
2965 }
2966 case relocInfo::virtual_call_type: return "virtual_call";
2967 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2968 case relocInfo::static_call_type: return "static_call";
2969 case relocInfo::static_stub_type: return "static_stub";
2970 case relocInfo::runtime_call_type: return "runtime_call";
2971 case relocInfo::external_word_type: return "external_word";
2972 case relocInfo::internal_word_type: return "internal_word";
2973 case relocInfo::section_word_type: return "section_word";
2974 case relocInfo::poll_type: return "poll";
2975 case relocInfo::poll_return_type: return "poll_return";
2976 case relocInfo::type_mask: return "type_bit_mask";
2977 }
2978 }
2979 return have_one ? "other" : NULL;
2980 }
2981
2982 // Return a the last scope in (begin..end]
2983 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2984 PcDesc* p = pc_desc_near(begin+1);
2985 if (p != NULL && p->real_pc(this) <= end) {
2986 return new ScopeDesc(this, p->scope_decode_offset(),
2987 p->obj_decode_offset(), p->should_reexecute(),
2988 p->return_oop());
2989 }
2990 return NULL;
2991 }
2992
2993 void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) const {
2994 if (block_begin == entry_point()) stream->print_cr("[Entry Point]");
2995 if (block_begin == verified_entry_point()) stream->print_cr("[Verified Entry Point]");
2996 if (block_begin == exception_begin()) stream->print_cr("[Exception Handler]");
2997 if (block_begin == stub_begin()) stream->print_cr("[Stub Code]");
2998 if (block_begin == deopt_handler_begin()) stream->print_cr("[Deopt Handler Code]");
2999
3000 if (has_method_handle_invokes())
3001 if (block_begin == deopt_mh_handler_begin()) stream->print_cr("[Deopt MH Handler Code]");
3002
3003 if (block_begin == consts_begin()) stream->print_cr("[Constants]");
3004
3005 if (block_begin == entry_point()) {
3006 methodHandle m = method();
3007 if (m.not_null()) {
3008 stream->print(" # ");
3009 m->print_value_on(stream);
3010 stream->cr();
3011 }
3012 if (m.not_null() && !is_osr_method()) {
3013 ResourceMark rm;
3014 int sizeargs = m->size_of_parameters();
3015 BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
3016 VMRegPair* regs = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
3017 {
3018 int sig_index = 0;
3019 if (!m->is_static())
3020 sig_bt[sig_index++] = T_OBJECT; // 'this'
3021 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
3022 BasicType t = ss.type();
3023 sig_bt[sig_index++] = t;
3024 if (type2size[t] == 2) {
3025 sig_bt[sig_index++] = T_VOID;
3026 } else {
3027 assert(type2size[t] == 1, "size is 1 or 2");
3028 }
3029 }
3030 assert(sig_index == sizeargs, "");
3031 }
3032 const char* spname = "sp"; // make arch-specific?
3033 intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
3034 int stack_slot_offset = this->frame_size() * wordSize;
3035 int tab1 = 14, tab2 = 24;
3036 int sig_index = 0;
3037 int arg_index = (m->is_static() ? 0 : -1);
3038 bool did_old_sp = false;
3039 for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
3040 bool at_this = (arg_index == -1);
3041 bool at_old_sp = false;
3042 BasicType t = (at_this ? T_OBJECT : ss.type());
3043 assert(t == sig_bt[sig_index], "sigs in sync");
3044 if (at_this)
3045 stream->print(" # this: ");
3046 else
3047 stream->print(" # parm%d: ", arg_index);
3048 stream->move_to(tab1);
3049 VMReg fst = regs[sig_index].first();
3050 VMReg snd = regs[sig_index].second();
3051 if (fst->is_reg()) {
3052 stream->print("%s", fst->name());
3053 if (snd->is_valid()) {
3054 stream->print(":%s", snd->name());
3055 }
3056 } else if (fst->is_stack()) {
3057 int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
3058 if (offset == stack_slot_offset) at_old_sp = true;
3059 stream->print("[%s+0x%x]", spname, offset);
3060 } else {
3061 stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
3062 }
3063 stream->print(" ");
3064 stream->move_to(tab2);
3065 stream->print("= ");
3066 if (at_this) {
3067 m->method_holder()->print_value_on(stream);
3068 } else {
3069 bool did_name = false;
3070 if (!at_this && ss.is_object()) {
3071 Symbol* name = ss.as_symbol_or_null();
3072 if (name != NULL) {
3073 name->print_value_on(stream);
3074 did_name = true;
3075 }
3076 }
3077 if (!did_name)
3078 stream->print("%s", type2name(t));
3079 }
3080 if (at_old_sp) {
3081 stream->print(" (%s of caller)", spname);
3082 did_old_sp = true;
3083 }
3084 stream->cr();
3085 sig_index += type2size[t];
3086 arg_index += 1;
3087 if (!at_this) ss.next();
3088 }
3089 if (!did_old_sp) {
3090 stream->print(" # ");
3091 stream->move_to(tab1);
3092 stream->print("[%s+0x%x]", spname, stack_slot_offset);
3093 stream->print(" (%s of caller)", spname);
3094 stream->cr();
3095 }
3096 }
3097 }
3098 }
3099
3100 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
3101 // First, find an oopmap in (begin, end].
3102 // We use the odd half-closed interval so that oop maps and scope descs
3103 // which are tied to the byte after a call are printed with the call itself.
3104 address base = code_begin();
3105 OopMapSet* oms = oop_maps();
3106 if (oms != NULL) {
3107 for (int i = 0, imax = oms->size(); i < imax; i++) {
3108 OopMap* om = oms->at(i);
3109 address pc = base + om->offset();
3110 if (pc > begin) {
3111 if (pc <= end) {
3112 st->move_to(column);
3113 st->print("; ");
3114 om->print_on(st);
3115 }
3116 break;
3117 }
3118 }
3119 }
3120
3121 // Print any debug info present at this pc.
3122 ScopeDesc* sd = scope_desc_in(begin, end);
3123 if (sd != NULL) {
3124 st->move_to(column);
3125 if (sd->bci() == SynchronizationEntryBCI) {
3126 st->print(";*synchronization entry");
3127 } else {
3128 if (sd->method() == NULL) {
3129 st->print("method is NULL");
3130 } else if (sd->method()->is_native()) {
3131 st->print("method is native");
3132 } else {
3133 Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
3134 st->print(";*%s", Bytecodes::name(bc));
3135 switch (bc) {
3136 case Bytecodes::_invokevirtual:
3137 case Bytecodes::_invokespecial:
3138 case Bytecodes::_invokestatic:
3139 case Bytecodes::_invokeinterface:
3140 {
3141 Bytecode_invoke invoke(sd->method(), sd->bci());
3142 st->print(" ");
3143 if (invoke.name() != NULL)
3144 invoke.name()->print_symbol_on(st);
3145 else
3146 st->print("<UNKNOWN>");
3147 break;
3148 }
3149 case Bytecodes::_getfield:
3150 case Bytecodes::_putfield:
3151 case Bytecodes::_getstatic:
3152 case Bytecodes::_putstatic:
3153 {
3154 Bytecode_field field(sd->method(), sd->bci());
3155 st->print(" ");
3156 if (field.name() != NULL)
3157 field.name()->print_symbol_on(st);
3158 else
3159 st->print("<UNKNOWN>");
3160 }
3161 }
3162 }
3163 }
3164
3165 // Print all scopes
3166 for (;sd != NULL; sd = sd->sender()) {
3167 st->move_to(column);
3168 st->print("; -");
3169 if (sd->method() == NULL) {
3170 st->print("method is NULL");
3171 } else {
3172 sd->method()->print_short_name(st);
3173 }
3174 int lineno = sd->method()->line_number_from_bci(sd->bci());
3175 if (lineno != -1) {
3176 st->print("@%d (line %d)", sd->bci(), lineno);
3177 } else {
3178 st->print("@%d", sd->bci());
3179 }
3180 st->cr();
3181 }
3182 }
3183
3184 // Print relocation information
3185 const char* str = reloc_string_for(begin, end);
3186 if (str != NULL) {
3187 if (sd != NULL) st->cr();
3188 st->move_to(column);
3189 st->print("; {%s}", str);
3190 }
3191 int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
3192 if (cont_offset != 0) {
3193 st->move_to(column);
3194 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
3195 }
3196
3197 }
3198
3199 #ifndef PRODUCT
3200
3201 void nmethod::print_value_on(outputStream* st) const {
3202 st->print("nmethod");
3203 print_on(st, NULL);
3204 }
3205
3206 void nmethod::print_calls(outputStream* st) {
3207 RelocIterator iter(this);
3208 while (iter.next()) {
3209 switch (iter.type()) {
3210 case relocInfo::virtual_call_type:
3211 case relocInfo::opt_virtual_call_type: {
3212 VerifyMutexLocker mc(CompiledIC_lock);
3213 CompiledIC_at(&iter)->print();
3214 break;
3215 }
3216 case relocInfo::static_call_type:
3217 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
3218 compiledStaticCall_at(iter.reloc())->print();
3219 break;
3220 }
3221 }
3222 }
3223
3224 void nmethod::print_handler_table() {
3225 ExceptionHandlerTable(this).print();
3226 }
3227
3228 void nmethod::print_nul_chk_table() {
3229 ImplicitExceptionTable(this).print(code_begin());
3230 }
3231
3232 void nmethod::print_statistics() {
3233 ttyLocker ttyl;
3234 if (xtty != NULL) xtty->head("statistics type='nmethod'");
3235 nmethod_stats.print_native_nmethod_stats();
3236 nmethod_stats.print_nmethod_stats();
3237 DebugInformationRecorder::print_statistics();
3238 nmethod_stats.print_pc_stats();
3239 Dependencies::print_statistics();
3240 if (xtty != NULL) xtty->tail("statistics");
3241 }
3242
3243 #endif // PRODUCT