1 /*
2 * Copyright 1997-2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 # include "incls/_precompiled.incl"
26 # include "incls/_nmethod.cpp.incl"
27
28 #ifdef DTRACE_ENABLED
29
30 // Only bother with this argument setup if dtrace is available
31
32 HS_DTRACE_PROBE_DECL8(hotspot, compiled__method__load,
33 const char*, int, const char*, int, const char*, int, void*, size_t);
34
35 HS_DTRACE_PROBE_DECL6(hotspot, compiled__method__unload,
36 char*, int, char*, int, char*, int);
37
38 #define DTRACE_METHOD_UNLOAD_PROBE(method) \
39 { \
40 methodOop m = (method); \
41 if (m != NULL) { \
42 symbolOop klass_name = m->klass_name(); \
43 symbolOop name = m->name(); \
44 symbolOop signature = m->signature(); \
45 HS_DTRACE_PROBE6(hotspot, compiled__method__unload, \
46 klass_name->bytes(), klass_name->utf8_length(), \
47 name->bytes(), name->utf8_length(), \
48 signature->bytes(), signature->utf8_length()); \
49 } \
50 }
51
52 #else // ndef DTRACE_ENABLED
53
54 #define DTRACE_METHOD_UNLOAD_PROBE(method)
55
56 #endif
57
58 bool nmethod::is_compiled_by_c1() const {
59 if (is_native_method()) return false;
60 assert(compiler() != NULL, "must be");
61 return compiler()->is_c1();
62 }
63 bool nmethod::is_compiled_by_c2() const {
64 if (is_native_method()) return false;
65 assert(compiler() != NULL, "must be");
66 return compiler()->is_c2();
67 }
68
69
70
71 //---------------------------------------------------------------------------------
72 // NMethod statistics
73 // They are printed under various flags, including:
74 // PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
75 // (In the latter two cases, they like other stats are printed to the log only.)
76
77 #ifndef PRODUCT
78 // These variables are put into one block to reduce relocations
79 // and make it simpler to print from the debugger.
80 static
81 struct nmethod_stats_struct {
82 int nmethod_count;
83 int total_size;
84 int relocation_size;
85 int code_size;
86 int stub_size;
87 int consts_size;
88 int scopes_data_size;
89 int scopes_pcs_size;
90 int dependencies_size;
91 int handler_table_size;
92 int nul_chk_table_size;
93 int oops_size;
94
95 void note_nmethod(nmethod* nm) {
96 nmethod_count += 1;
97 total_size += nm->size();
98 relocation_size += nm->relocation_size();
99 code_size += nm->code_size();
100 stub_size += nm->stub_size();
101 consts_size += nm->consts_size();
102 scopes_data_size += nm->scopes_data_size();
103 scopes_pcs_size += nm->scopes_pcs_size();
104 dependencies_size += nm->dependencies_size();
105 handler_table_size += nm->handler_table_size();
106 nul_chk_table_size += nm->nul_chk_table_size();
107 oops_size += nm->oops_size();
108 }
109 void print_nmethod_stats() {
110 if (nmethod_count == 0) return;
111 tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
112 if (total_size != 0) tty->print_cr(" total in heap = %d", total_size);
113 if (relocation_size != 0) tty->print_cr(" relocation = %d", relocation_size);
114 if (code_size != 0) tty->print_cr(" main code = %d", code_size);
115 if (stub_size != 0) tty->print_cr(" stub code = %d", stub_size);
116 if (consts_size != 0) tty->print_cr(" constants = %d", consts_size);
117 if (scopes_data_size != 0) tty->print_cr(" scopes data = %d", scopes_data_size);
118 if (scopes_pcs_size != 0) tty->print_cr(" scopes pcs = %d", scopes_pcs_size);
119 if (dependencies_size != 0) tty->print_cr(" dependencies = %d", dependencies_size);
120 if (handler_table_size != 0) tty->print_cr(" handler table = %d", handler_table_size);
121 if (nul_chk_table_size != 0) tty->print_cr(" nul chk table = %d", nul_chk_table_size);
122 if (oops_size != 0) tty->print_cr(" oops = %d", oops_size);
123 }
124
125 int native_nmethod_count;
126 int native_total_size;
127 int native_relocation_size;
128 int native_code_size;
129 int native_oops_size;
130 void note_native_nmethod(nmethod* nm) {
131 native_nmethod_count += 1;
132 native_total_size += nm->size();
133 native_relocation_size += nm->relocation_size();
134 native_code_size += nm->code_size();
135 native_oops_size += nm->oops_size();
136 }
137 void print_native_nmethod_stats() {
138 if (native_nmethod_count == 0) return;
139 tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
140 if (native_total_size != 0) tty->print_cr(" N. total size = %d", native_total_size);
141 if (native_relocation_size != 0) tty->print_cr(" N. relocation = %d", native_relocation_size);
142 if (native_code_size != 0) tty->print_cr(" N. main code = %d", native_code_size);
143 if (native_oops_size != 0) tty->print_cr(" N. oops = %d", native_oops_size);
144 }
145
146 int pc_desc_resets; // number of resets (= number of caches)
147 int pc_desc_queries; // queries to nmethod::find_pc_desc
148 int pc_desc_approx; // number of those which have approximate true
149 int pc_desc_repeats; // number of _last_pc_desc hits
150 int pc_desc_hits; // number of LRU cache hits
151 int pc_desc_tests; // total number of PcDesc examinations
152 int pc_desc_searches; // total number of quasi-binary search steps
153 int pc_desc_adds; // number of LUR cache insertions
154
155 void print_pc_stats() {
156 tty->print_cr("PcDesc Statistics: %d queries, %.2f comparisons per query",
157 pc_desc_queries,
158 (double)(pc_desc_tests + pc_desc_searches)
159 / pc_desc_queries);
160 tty->print_cr(" caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
161 pc_desc_resets,
162 pc_desc_queries, pc_desc_approx,
163 pc_desc_repeats, pc_desc_hits,
164 pc_desc_tests, pc_desc_searches, pc_desc_adds);
165 }
166 } nmethod_stats;
167 #endif //PRODUCT
168
169 //---------------------------------------------------------------------------------
170
171
172 // The _unwind_handler is a special marker address, which says that
173 // for given exception oop and address, the frame should be removed
174 // as the tuple cannot be caught in the nmethod
175 address ExceptionCache::_unwind_handler = (address) -1;
176
177
178 ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
179 assert(pc != NULL, "Must be non null");
180 assert(exception.not_null(), "Must be non null");
181 assert(handler != NULL, "Must be non null");
182
183 _count = 0;
184 _exception_type = exception->klass();
185 _next = NULL;
186
187 add_address_and_handler(pc,handler);
188 }
189
190
191 address ExceptionCache::match(Handle exception, address pc) {
192 assert(pc != NULL,"Must be non null");
193 assert(exception.not_null(),"Must be non null");
194 if (exception->klass() == exception_type()) {
195 return (test_address(pc));
196 }
197
198 return NULL;
199 }
200
201
202 bool ExceptionCache::match_exception_with_space(Handle exception) {
203 assert(exception.not_null(),"Must be non null");
204 if (exception->klass() == exception_type() && count() < cache_size) {
205 return true;
206 }
207 return false;
208 }
209
210
211 address ExceptionCache::test_address(address addr) {
212 for (int i=0; i<count(); i++) {
213 if (pc_at(i) == addr) {
214 return handler_at(i);
215 }
216 }
217 return NULL;
218 }
219
220
221 bool ExceptionCache::add_address_and_handler(address addr, address handler) {
222 if (test_address(addr) == handler) return true;
223 if (count() < cache_size) {
224 set_pc_at(count(),addr);
225 set_handler_at(count(), handler);
226 increment_count();
227 return true;
228 }
229 return false;
230 }
231
232
233 // private method for handling exception cache
234 // These methods are private, and used to manipulate the exception cache
235 // directly.
236 ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
237 ExceptionCache* ec = exception_cache();
238 while (ec != NULL) {
239 if (ec->match_exception_with_space(exception)) {
240 return ec;
241 }
242 ec = ec->next();
243 }
244 return NULL;
245 }
246
247
248 //-----------------------------------------------------------------------------
249
250
251 // Helper used by both find_pc_desc methods.
252 static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
253 NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
254 if (!approximate)
255 return pc->pc_offset() == pc_offset;
256 else
257 return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
258 }
259
260 void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
261 if (initial_pc_desc == NULL) {
262 _last_pc_desc = NULL; // native method
263 return;
264 }
265 NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
266 // reset the cache by filling it with benign (non-null) values
267 assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
268 _last_pc_desc = initial_pc_desc + 1; // first valid one is after sentinel
269 for (int i = 0; i < cache_size; i++)
270 _pc_descs[i] = initial_pc_desc;
271 }
272
273 PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
274 NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
275 NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
276
277 // In order to prevent race conditions do not load cache elements
278 // repeatedly, but use a local copy:
279 PcDesc* res;
280
281 // Step one: Check the most recently returned value.
282 res = _last_pc_desc;
283 if (res == NULL) return NULL; // native method; no PcDescs at all
284 if (match_desc(res, pc_offset, approximate)) {
285 NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
286 return res;
287 }
288
289 // Step two: Check the LRU cache.
290 for (int i = 0; i < cache_size; i++) {
291 res = _pc_descs[i];
292 if (res->pc_offset() < 0) break; // optimization: skip empty cache
293 if (match_desc(res, pc_offset, approximate)) {
294 NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
295 _last_pc_desc = res; // record this cache hit in case of repeat
296 return res;
297 }
298 }
299
300 // Report failure.
301 return NULL;
302 }
303
304 void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
305 NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
306 // Update the LRU cache by shifting pc_desc forward:
307 for (int i = 0; i < cache_size; i++) {
308 PcDesc* next = _pc_descs[i];
309 _pc_descs[i] = pc_desc;
310 pc_desc = next;
311 }
312 // Note: Do not update _last_pc_desc. It fronts for the LRU cache.
313 }
314
315 // adjust pcs_size so that it is a multiple of both oopSize and
316 // sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
317 // of oopSize, then 2*sizeof(PcDesc) is)
318 static int adjust_pcs_size(int pcs_size) {
319 int nsize = round_to(pcs_size, oopSize);
320 if ((nsize % sizeof(PcDesc)) != 0) {
321 nsize = pcs_size + sizeof(PcDesc);
322 }
323 assert((nsize % oopSize) == 0, "correct alignment");
324 return nsize;
325 }
326
327 //-----------------------------------------------------------------------------
328
329
330 void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
331 assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
332 assert(new_entry != NULL,"Must be non null");
333 assert(new_entry->next() == NULL, "Must be null");
334
335 if (exception_cache() != NULL) {
336 new_entry->set_next(exception_cache());
337 }
338 set_exception_cache(new_entry);
339 }
340
341 void nmethod::remove_from_exception_cache(ExceptionCache* ec) {
342 ExceptionCache* prev = NULL;
343 ExceptionCache* curr = exception_cache();
344 assert(curr != NULL, "nothing to remove");
345 // find the previous and next entry of ec
346 while (curr != ec) {
347 prev = curr;
348 curr = curr->next();
349 assert(curr != NULL, "ExceptionCache not found");
350 }
351 // now: curr == ec
352 ExceptionCache* next = curr->next();
353 if (prev == NULL) {
354 set_exception_cache(next);
355 } else {
356 prev->set_next(next);
357 }
358 delete curr;
359 }
360
361
362 // public method for accessing the exception cache
363 // These are the public access methods.
364 address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
365 // We never grab a lock to read the exception cache, so we may
366 // have false negatives. This is okay, as it can only happen during
367 // the first few exception lookups for a given nmethod.
368 ExceptionCache* ec = exception_cache();
369 while (ec != NULL) {
370 address ret_val;
371 if ((ret_val = ec->match(exception,pc)) != NULL) {
372 return ret_val;
373 }
374 ec = ec->next();
375 }
376 return NULL;
377 }
378
379
380 void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
381 // There are potential race conditions during exception cache updates, so we
382 // must own the ExceptionCache_lock before doing ANY modifications. Because
383 // we don't lock during reads, it is possible to have several threads attempt
384 // to update the cache with the same data. We need to check for already inserted
385 // copies of the current data before adding it.
386
387 MutexLocker ml(ExceptionCache_lock);
388 ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
389
390 if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
391 target_entry = new ExceptionCache(exception,pc,handler);
392 add_exception_cache_entry(target_entry);
393 }
394 }
395
396
397 //-------------end of code for ExceptionCache--------------
398
399
400 void nmFlags::clear() {
401 assert(sizeof(nmFlags) == sizeof(int), "using more than one word for nmFlags");
402 *(jint*)this = 0;
403 }
404
405 int nmethod::total_size() const {
406 return
407 code_size() +
408 stub_size() +
409 consts_size() +
410 scopes_data_size() +
411 scopes_pcs_size() +
412 handler_table_size() +
413 nul_chk_table_size();
414 }
415
416 const char* nmethod::compile_kind() const {
417 if (method() == NULL) return "unloaded";
418 if (is_native_method()) return "c2n";
419 if (is_osr_method()) return "osr";
420 return NULL;
421 }
422
423 // %%% This variable is no longer used?
424 int nmethod::_zombie_instruction_size = NativeJump::instruction_size;
425
426
427 nmethod* nmethod::new_native_nmethod(methodHandle method,
428 CodeBuffer *code_buffer,
429 int vep_offset,
430 int frame_complete,
431 int frame_size,
432 ByteSize basic_lock_owner_sp_offset,
433 ByteSize basic_lock_sp_offset,
434 OopMapSet* oop_maps) {
435 // create nmethod
436 nmethod* nm = NULL;
437 {
438 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
439 int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
440 CodeOffsets offsets;
441 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
442 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
443 nm = new (native_nmethod_size)
444 nmethod(method(), native_nmethod_size, &offsets,
445 code_buffer, frame_size,
446 basic_lock_owner_sp_offset, basic_lock_sp_offset,
447 oop_maps);
448 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm));
449 if (PrintAssembly && nm != NULL)
450 Disassembler::decode(nm);
451 }
452 // verify nmethod
453 debug_only(if (nm) nm->verify();) // might block
454
455 if (nm != NULL) {
456 nm->log_new_nmethod();
457 }
458
459 return nm;
460 }
461
462 #ifdef HAVE_DTRACE_H
463 nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
464 CodeBuffer *code_buffer,
465 int vep_offset,
466 int trap_offset,
467 int frame_complete,
468 int frame_size) {
469 // create nmethod
470 nmethod* nm = NULL;
471 {
472 MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
473 int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
474 CodeOffsets offsets;
475 offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
476 offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
477 offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
478
479 nm = new (nmethod_size) nmethod(method(), nmethod_size, &offsets, code_buffer, frame_size);
480
481 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
482 if (PrintAssembly && nm != NULL)
483 Disassembler::decode(nm);
484 }
485 // verify nmethod
486 debug_only(if (nm) nm->verify();) // might block
487
488 if (nm != NULL) {
489 nm->log_new_nmethod();
490 }
491
492 return nm;
493 }
494
495 #endif // def HAVE_DTRACE_H
496
497 nmethod* nmethod::new_nmethod(methodHandle method,
498 int compile_id,
499 int entry_bci,
500 CodeOffsets* offsets,
501 int orig_pc_offset,
502 DebugInformationRecorder* debug_info,
503 Dependencies* dependencies,
504 CodeBuffer* code_buffer, int frame_size,
505 OopMapSet* oop_maps,
506 ExceptionHandlerTable* handler_table,
507 ImplicitExceptionTable* nul_chk_table,
508 AbstractCompiler* compiler,
509 int comp_level
510 )
511 {
512 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
513 // create nmethod
514 nmethod* nm = NULL;
515 { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
516 int nmethod_size =
517 allocation_size(code_buffer, sizeof(nmethod))
518 + adjust_pcs_size(debug_info->pcs_size())
519 + round_to(dependencies->size_in_bytes() , oopSize)
520 + round_to(handler_table->size_in_bytes(), oopSize)
521 + round_to(nul_chk_table->size_in_bytes(), oopSize)
522 + round_to(debug_info->data_size() , oopSize);
523 nm = new (nmethod_size)
524 nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
525 orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
526 oop_maps,
527 handler_table,
528 nul_chk_table,
529 compiler,
530 comp_level);
531 if (nm != NULL) {
532 // To make dependency checking during class loading fast, record
533 // the nmethod dependencies in the classes it is dependent on.
534 // This allows the dependency checking code to simply walk the
535 // class hierarchy above the loaded class, checking only nmethods
536 // which are dependent on those classes. The slow way is to
537 // check every nmethod for dependencies which makes it linear in
538 // the number of methods compiled. For applications with a lot
539 // classes the slow way is too slow.
540 for (Dependencies::DepStream deps(nm); deps.next(); ) {
541 klassOop klass = deps.context_type();
542 if (klass == NULL) continue; // ignore things like evol_method
543
544 // record this nmethod as dependent on this klass
545 instanceKlass::cast(klass)->add_dependent_nmethod(nm);
546 }
547 }
548 NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm));
549 if (PrintAssembly && nm != NULL)
550 Disassembler::decode(nm);
551 }
552
553 // verify nmethod
554 debug_only(if (nm) nm->verify();) // might block
555
556 if (nm != NULL) {
557 nm->log_new_nmethod();
558 }
559
560 // done
561 return nm;
562 }
563
564
565 // For native wrappers
566 nmethod::nmethod(
567 methodOop method,
568 int nmethod_size,
569 CodeOffsets* offsets,
570 CodeBuffer* code_buffer,
571 int frame_size,
572 ByteSize basic_lock_owner_sp_offset,
573 ByteSize basic_lock_sp_offset,
574 OopMapSet* oop_maps )
575 : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
576 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
577 _compiled_synchronized_native_basic_lock_owner_sp_offset(basic_lock_owner_sp_offset),
578 _compiled_synchronized_native_basic_lock_sp_offset(basic_lock_sp_offset)
579 {
580 {
581 debug_only(No_Safepoint_Verifier nsv;)
582 assert_locked_or_safepoint(CodeCache_lock);
583
584 NOT_PRODUCT(_has_debug_info = false; )
585 _method = method;
586 _entry_bci = InvocationEntryBci;
587 _link = NULL;
588 _compiler = NULL;
589 // We have no exception handler or deopt handler make the
590 // values something that will never match a pc like the nmethod vtable entry
591 _exception_offset = 0;
592 _deoptimize_offset = 0;
593 _orig_pc_offset = 0;
594 #ifdef HAVE_DTRACE_H
595 _trap_offset = 0;
596 #endif // def HAVE_DTRACE_H
597 _stub_offset = data_offset();
598 _consts_offset = data_offset();
599 _scopes_data_offset = data_offset();
600 _scopes_pcs_offset = _scopes_data_offset;
601 _dependencies_offset = _scopes_pcs_offset;
602 _handler_table_offset = _dependencies_offset;
603 _nul_chk_table_offset = _handler_table_offset;
604 _nmethod_end_offset = _nul_chk_table_offset;
605 _compile_id = 0; // default
606 _comp_level = CompLevel_none;
607 _entry_point = instructions_begin();
608 _verified_entry_point = instructions_begin() + offsets->value(CodeOffsets::Verified_Entry);
609 _osr_entry_point = NULL;
610 _exception_cache = NULL;
611 _pc_desc_cache.reset_to(NULL);
612
613 flags.clear();
614 flags.state = alive;
615 _markedForDeoptimization = 0;
616
617 _lock_count = 0;
618 _stack_traversal_mark = 0;
619
620 code_buffer->copy_oops_to(this);
621 debug_only(check_store();)
622 CodeCache::commit(this);
623 VTune::create_nmethod(this);
624 }
625
626 if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
627 ttyLocker ttyl; // keep the following output all in one block
628 // This output goes directly to the tty, not the compiler log.
629 // To enable tools to match it up with the compilation activity,
630 // be sure to tag this tty output with the compile ID.
631 if (xtty != NULL) {
632 xtty->begin_head("print_native_nmethod");
633 xtty->method(_method);
634 xtty->stamp();
635 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
636 }
637 // print the header part first
638 print();
639 // then print the requested information
640 if (PrintNativeNMethods) {
641 print_code();
642 oop_maps->print();
643 }
644 if (PrintRelocations) {
645 print_relocations();
646 }
647 if (xtty != NULL) {
648 xtty->tail("print_native_nmethod");
649 }
650 }
651 Events::log("Create nmethod " INTPTR_FORMAT, this);
652 }
653
654 // For dtrace wrappers
655 #ifdef HAVE_DTRACE_H
656 nmethod::nmethod(
657 methodOop method,
658 int nmethod_size,
659 CodeOffsets* offsets,
660 CodeBuffer* code_buffer,
661 int frame_size)
662 : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
663 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
664 _compiled_synchronized_native_basic_lock_owner_sp_offset(in_ByteSize(-1)),
665 _compiled_synchronized_native_basic_lock_sp_offset(in_ByteSize(-1))
666 {
667 {
668 debug_only(No_Safepoint_Verifier nsv;)
669 assert_locked_or_safepoint(CodeCache_lock);
670
671 NOT_PRODUCT(_has_debug_info = false; )
672 _method = method;
673 _entry_bci = InvocationEntryBci;
674 _link = NULL;
675 _compiler = NULL;
676 // We have no exception handler or deopt handler make the
677 // values something that will never match a pc like the nmethod vtable entry
678 _exception_offset = 0;
679 _deoptimize_offset = 0;
680 _trap_offset = offsets->value(CodeOffsets::Dtrace_trap);
681 _orig_pc_offset = 0;
682 _stub_offset = data_offset();
683 _consts_offset = data_offset();
684 _scopes_data_offset = data_offset();
685 _scopes_pcs_offset = _scopes_data_offset;
686 _dependencies_offset = _scopes_pcs_offset;
687 _handler_table_offset = _dependencies_offset;
688 _nul_chk_table_offset = _handler_table_offset;
689 _nmethod_end_offset = _nul_chk_table_offset;
690 _compile_id = 0; // default
691 _comp_level = CompLevel_none;
692 _entry_point = instructions_begin();
693 _verified_entry_point = instructions_begin() + offsets->value(CodeOffsets::Verified_Entry);
694 _osr_entry_point = NULL;
695 _exception_cache = NULL;
696 _pc_desc_cache.reset_to(NULL);
697
698 flags.clear();
699 flags.state = alive;
700 _markedForDeoptimization = 0;
701
702 _lock_count = 0;
703 _stack_traversal_mark = 0;
704
705 code_buffer->copy_oops_to(this);
706 debug_only(check_store();)
707 CodeCache::commit(this);
708 VTune::create_nmethod(this);
709 }
710
711 if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
712 ttyLocker ttyl; // keep the following output all in one block
713 // This output goes directly to the tty, not the compiler log.
714 // To enable tools to match it up with the compilation activity,
715 // be sure to tag this tty output with the compile ID.
716 if (xtty != NULL) {
717 xtty->begin_head("print_dtrace_nmethod");
718 xtty->method(_method);
719 xtty->stamp();
720 xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
721 }
722 // print the header part first
723 print();
724 // then print the requested information
725 if (PrintNMethods) {
726 print_code();
727 }
728 if (PrintRelocations) {
729 print_relocations();
730 }
731 if (xtty != NULL) {
732 xtty->tail("print_dtrace_nmethod");
733 }
734 }
735 Events::log("Create nmethod " INTPTR_FORMAT, this);
736 }
737 #endif // def HAVE_DTRACE_H
738
739 void* nmethod::operator new(size_t size, int nmethod_size) {
740 // Always leave some room in the CodeCache for I2C/C2I adapters
741 if (CodeCache::unallocated_capacity() < CodeCacheMinimumFreeSpace) return NULL;
742 return CodeCache::allocate(nmethod_size);
743 }
744
745
746 nmethod::nmethod(
747 methodOop method,
748 int nmethod_size,
749 int compile_id,
750 int entry_bci,
751 CodeOffsets* offsets,
752 int orig_pc_offset,
753 DebugInformationRecorder* debug_info,
754 Dependencies* dependencies,
755 CodeBuffer *code_buffer,
756 int frame_size,
757 OopMapSet* oop_maps,
758 ExceptionHandlerTable* handler_table,
759 ImplicitExceptionTable* nul_chk_table,
760 AbstractCompiler* compiler,
761 int comp_level
762 )
763 : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
764 nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
765 _compiled_synchronized_native_basic_lock_owner_sp_offset(in_ByteSize(-1)),
766 _compiled_synchronized_native_basic_lock_sp_offset(in_ByteSize(-1))
767 {
768 assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
769 {
770 debug_only(No_Safepoint_Verifier nsv;)
771 assert_locked_or_safepoint(CodeCache_lock);
772
773 NOT_PRODUCT(_has_debug_info = false; )
774 _method = method;
775 _compile_id = compile_id;
776 _comp_level = comp_level;
777 _entry_bci = entry_bci;
778 _link = NULL;
779 _compiler = compiler;
780 _orig_pc_offset = orig_pc_offset;
781 #ifdef HAVE_DTRACE_H
782 _trap_offset = 0;
783 #endif // def HAVE_DTRACE_H
784 _stub_offset = instructions_offset() + code_buffer->total_offset_of(code_buffer->stubs()->start());
785
786 // Exception handler and deopt handler are in the stub section
787 _exception_offset = _stub_offset + offsets->value(CodeOffsets::Exceptions);
788 _deoptimize_offset = _stub_offset + offsets->value(CodeOffsets::Deopt);
789 _consts_offset = instructions_offset() + code_buffer->total_offset_of(code_buffer->consts()->start());
790 _scopes_data_offset = data_offset();
791 _scopes_pcs_offset = _scopes_data_offset + round_to(debug_info->data_size (), oopSize);
792 _dependencies_offset = _scopes_pcs_offset + adjust_pcs_size(debug_info->pcs_size());
793 _handler_table_offset = _dependencies_offset + round_to(dependencies->size_in_bytes (), oopSize);
794 _nul_chk_table_offset = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
795 _nmethod_end_offset = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
796
797 _entry_point = instructions_begin();
798 _verified_entry_point = instructions_begin() + offsets->value(CodeOffsets::Verified_Entry);
799 _osr_entry_point = instructions_begin() + offsets->value(CodeOffsets::OSR_Entry);
800 _exception_cache = NULL;
801 _pc_desc_cache.reset_to(scopes_pcs_begin());
802
803 flags.clear();
804 flags.state = alive;
805 _markedForDeoptimization = 0;
806
807 _unload_reported = false; // jvmti state
808
809 _lock_count = 0;
810 _stack_traversal_mark = 0;
811
812 // Copy contents of ScopeDescRecorder to nmethod
813 code_buffer->copy_oops_to(this);
814 debug_info->copy_to(this);
815 dependencies->copy_to(this);
816 debug_only(check_store();)
817
818 CodeCache::commit(this);
819
820 VTune::create_nmethod(this);
821
822 // Copy contents of ExceptionHandlerTable to nmethod
823 handler_table->copy_to(this);
824 nul_chk_table->copy_to(this);
825
826 // we use the information of entry points to find out if a method is
827 // static or non static
828 assert(compiler->is_c2() ||
829 _method->is_static() == (entry_point() == _verified_entry_point),
830 " entry points must be same for static methods and vice versa");
831 }
832
833 bool printnmethods = PrintNMethods
834 || CompilerOracle::should_print(_method)
835 || CompilerOracle::has_option_string(_method, "PrintNMethods");
836 if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
837 print_nmethod(printnmethods);
838 }
839
840 // Note: Do not verify in here as the CodeCache_lock is
841 // taken which would conflict with the CompiledIC_lock
842 // which taken during the verification of call sites.
843 // (was bug - gri 10/25/99)
844
845 Events::log("Create nmethod " INTPTR_FORMAT, this);
846 }
847
848
849 // Print a short set of xml attributes to identify this nmethod. The
850 // output should be embedded in some other element.
851 void nmethod::log_identity(xmlStream* log) const {
852 log->print(" compile_id='%d'", compile_id());
853 const char* nm_kind = compile_kind();
854 if (nm_kind != NULL) log->print(" compile_kind='%s'", nm_kind);
855 if (compiler() != NULL) {
856 log->print(" compiler='%s'", compiler()->name());
857 }
858 #ifdef TIERED
859 log->print(" level='%d'", comp_level());
860 #endif // TIERED
861 }
862
863
864 #define LOG_OFFSET(log, name) \
865 if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
866 log->print(" " XSTR(name) "_offset='%d'" , \
867 (intptr_t)name##_begin() - (intptr_t)this)
868
869
870 void nmethod::log_new_nmethod() const {
871 if (LogCompilation && xtty != NULL) {
872 ttyLocker ttyl;
873 HandleMark hm;
874 xtty->begin_elem("nmethod");
875 log_identity(xtty);
876 xtty->print(" entry='" INTPTR_FORMAT "' size='%d'",
877 instructions_begin(), size());
878 xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
879
880 LOG_OFFSET(xtty, relocation);
881 LOG_OFFSET(xtty, code);
882 LOG_OFFSET(xtty, stub);
883 LOG_OFFSET(xtty, consts);
884 LOG_OFFSET(xtty, scopes_data);
885 LOG_OFFSET(xtty, scopes_pcs);
886 LOG_OFFSET(xtty, dependencies);
887 LOG_OFFSET(xtty, handler_table);
888 LOG_OFFSET(xtty, nul_chk_table);
889 LOG_OFFSET(xtty, oops);
890
891 xtty->method(method());
892 xtty->stamp();
893 xtty->end_elem();
894 }
895 }
896
897 #undef LOG_OFFSET
898
899
900 // Print out more verbose output usually for a newly created nmethod.
901 void nmethod::print_on(outputStream* st, const char* title) const {
902 if (st != NULL) {
903 ttyLocker ttyl;
904 // Print a little tag line that looks like +PrintCompilation output:
905 st->print("%3d%c %s",
906 compile_id(),
907 is_osr_method() ? '%' :
908 method() != NULL &&
909 is_native_method() ? 'n' : ' ',
910 title);
911 #ifdef TIERED
912 st->print(" (%d) ", comp_level());
913 #endif // TIERED
914 if (WizardMode) st->print(" (" INTPTR_FORMAT ")", this);
915 if (method() != NULL) {
916 method()->print_short_name(st);
917 if (is_osr_method())
918 st->print(" @ %d", osr_entry_bci());
919 if (method()->code_size() > 0)
920 st->print(" (%d bytes)", method()->code_size());
921 }
922 }
923 }
924
925
926 void nmethod::print_nmethod(bool printmethod) {
927 ttyLocker ttyl; // keep the following output all in one block
928 if (xtty != NULL) {
929 xtty->begin_head("print_nmethod");
930 xtty->stamp();
931 xtty->end_head();
932 }
933 // print the header part first
934 print();
935 // then print the requested information
936 if (printmethod) {
937 print_code();
938 print_pcs();
939 oop_maps()->print();
940 }
941 if (PrintDebugInfo) {
942 print_scopes();
943 }
944 if (PrintRelocations) {
945 print_relocations();
946 }
947 if (PrintDependencies) {
948 print_dependencies();
949 }
950 if (PrintExceptionHandlers) {
951 print_handler_table();
952 print_nul_chk_table();
953 }
954 if (xtty != NULL) {
955 xtty->tail("print_nmethod");
956 }
957 }
958
959
960 void nmethod::set_version(int v) {
961 flags.version = v;
962 }
963
964
965 ScopeDesc* nmethod::scope_desc_at(address pc) {
966 PcDesc* pd = pc_desc_at(pc);
967 guarantee(pd != NULL, "scope must be present");
968 return new ScopeDesc(this, pd->scope_decode_offset(),
969 pd->obj_decode_offset(), pd->should_reexecute());
970 }
971
972
973 void nmethod::clear_inline_caches() {
974 assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
975 if (is_zombie()) {
976 return;
977 }
978
979 RelocIterator iter(this);
980 while (iter.next()) {
981 iter.reloc()->clear_inline_cache();
982 }
983 }
984
985
986 void nmethod::cleanup_inline_caches() {
987
988 assert(SafepointSynchronize::is_at_safepoint() &&
989 !CompiledIC_lock->is_locked() &&
990 !Patching_lock->is_locked(), "no threads must be updating the inline caches by them selfs");
991
992 // If the method is not entrant or zombie then a JMP is plastered over the
993 // first few bytes. If an oop in the old code was there, that oop
994 // should not get GC'd. Skip the first few bytes of oops on
995 // not-entrant methods.
996 address low_boundary = verified_entry_point();
997 if (!is_in_use()) {
998 low_boundary += NativeJump::instruction_size;
999 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1000 // This means that the low_boundary is going to be a little too high.
1001 // This shouldn't matter, since oops of non-entrant methods are never used.
1002 // In fact, why are we bothering to look at oops in a non-entrant method??
1003 }
1004
1005 // Find all calls in an nmethod, and clear the ones that points to zombie methods
1006 ResourceMark rm;
1007 RelocIterator iter(this, low_boundary);
1008 while(iter.next()) {
1009 switch(iter.type()) {
1010 case relocInfo::virtual_call_type:
1011 case relocInfo::opt_virtual_call_type: {
1012 CompiledIC *ic = CompiledIC_at(iter.reloc());
1013 // Ok, to lookup references to zombies here
1014 CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1015 if( cb != NULL && cb->is_nmethod() ) {
1016 nmethod* nm = (nmethod*)cb;
1017 // Clean inline caches pointing to both zombie and not_entrant methods
1018 if (!nm->is_in_use()) ic->set_to_clean();
1019 }
1020 break;
1021 }
1022 case relocInfo::static_call_type: {
1023 CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1024 CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1025 if( cb != NULL && cb->is_nmethod() ) {
1026 nmethod* nm = (nmethod*)cb;
1027 // Clean inline caches pointing to both zombie and not_entrant methods
1028 if (!nm->is_in_use()) csc->set_to_clean();
1029 }
1030 break;
1031 }
1032 }
1033 }
1034 }
1035
1036 void nmethod::mark_as_seen_on_stack() {
1037 assert(is_not_entrant(), "must be a non-entrant method");
1038 set_stack_traversal_mark(NMethodSweeper::traversal_count());
1039 }
1040
1041 // Tell if a non-entrant method can be converted to a zombie (i.e., there is no activations on the stack)
1042 bool nmethod::can_not_entrant_be_converted() {
1043 assert(is_not_entrant(), "must be a non-entrant method");
1044 assert(SafepointSynchronize::is_at_safepoint(), "must be called during a safepoint");
1045
1046 // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1047 // count can be greater than the stack traversal count before it hits the
1048 // nmethod for the second time.
1049 return stack_traversal_mark()+1 < NMethodSweeper::traversal_count();
1050 }
1051
1052 void nmethod::inc_decompile_count() {
1053 // Could be gated by ProfileTraps, but do not bother...
1054 methodOop m = method();
1055 if (m == NULL) return;
1056 methodDataOop mdo = m->method_data();
1057 if (mdo == NULL) return;
1058 // There is a benign race here. See comments in methodDataOop.hpp.
1059 mdo->inc_decompile_count();
1060 }
1061
1062 void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1063
1064 post_compiled_method_unload();
1065
1066 // Since this nmethod is being unloaded, make sure that dependencies
1067 // recorded in instanceKlasses get flushed and pass non-NULL closure to
1068 // indicate that this work is being done during a GC.
1069 assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1070 assert(is_alive != NULL, "Should be non-NULL");
1071 // A non-NULL is_alive closure indicates that this is being called during GC.
1072 flush_dependencies(is_alive);
1073
1074 // Break cycle between nmethod & method
1075 if (TraceClassUnloading && WizardMode) {
1076 tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1077 " unloadable], methodOop(" INTPTR_FORMAT
1078 "), cause(" INTPTR_FORMAT ")",
1079 this, (address)_method, (address)cause);
1080 cause->klass()->print();
1081 }
1082 // If _method is already NULL the methodOop is about to be unloaded,
1083 // so we don't have to break the cycle. Note that it is possible to
1084 // have the methodOop live here, in case we unload the nmethod because
1085 // it is pointing to some oop (other than the methodOop) being unloaded.
1086 if (_method != NULL) {
1087 // OSR methods point to the methodOop, but the methodOop does not
1088 // point back!
1089 if (_method->code() == this) {
1090 _method->clear_code(); // Break a cycle
1091 }
1092 inc_decompile_count(); // Last chance to make a mark on the MDO
1093 _method = NULL; // Clear the method of this dead nmethod
1094 }
1095 // Make the class unloaded - i.e., change state and notify sweeper
1096 check_safepoint();
1097 if (is_in_use()) {
1098 // Transitioning directly from live to unloaded -- so
1099 // we need to force a cache clean-up; remember this
1100 // for later on.
1101 CodeCache::set_needs_cache_clean(true);
1102 }
1103 flags.state = unloaded;
1104
1105 // The methodOop is gone at this point
1106 assert(_method == NULL, "Tautology");
1107
1108 set_link(NULL);
1109 NMethodSweeper::notify(this);
1110 }
1111
1112 void nmethod::invalidate_osr_method() {
1113 assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1114 if (_entry_bci != InvalidOSREntryBci)
1115 inc_decompile_count();
1116 // Remove from list of active nmethods
1117 if (method() != NULL)
1118 instanceKlass::cast(method()->method_holder())->remove_osr_nmethod(this);
1119 // Set entry as invalid
1120 _entry_bci = InvalidOSREntryBci;
1121 }
1122
1123 void nmethod::log_state_change(int state) const {
1124 if (LogCompilation) {
1125 if (xtty != NULL) {
1126 ttyLocker ttyl; // keep the following output all in one block
1127 xtty->begin_elem("make_not_entrant %sthread='" UINTX_FORMAT "'",
1128 (state == zombie ? "zombie='1' " : ""),
1129 os::current_thread_id());
1130 log_identity(xtty);
1131 xtty->stamp();
1132 xtty->end_elem();
1133 }
1134 }
1135 if (PrintCompilation) {
1136 print_on(tty, state == zombie ? "made zombie " : "made not entrant ");
1137 tty->cr();
1138 }
1139 }
1140
1141 // Common functionality for both make_not_entrant and make_zombie
1142 void nmethod::make_not_entrant_or_zombie(int state) {
1143 assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1144
1145 // Code for an on-stack-replacement nmethod is removed when a class gets unloaded.
1146 // They never become zombie/non-entrant, so the nmethod sweeper will never remove
1147 // them. Instead the entry_bci is set to InvalidOSREntryBci, so the osr nmethod
1148 // will never be used anymore. That the nmethods only gets removed when class unloading
1149 // happens, make life much simpler, since the nmethods are not just going to disappear
1150 // out of the blue.
1151 if (is_osr_only_method()) {
1152 if (osr_entry_bci() != InvalidOSREntryBci) {
1153 // only log this once
1154 log_state_change(state);
1155 }
1156 invalidate_osr_method();
1157 return;
1158 }
1159
1160 // If the method is already zombie or set to the state we want, nothing to do
1161 if (is_zombie() || (state == not_entrant && is_not_entrant())) {
1162 return;
1163 }
1164
1165 log_state_change(state);
1166
1167 // Make sure the nmethod is not flushed in case of a safepoint in code below.
1168 nmethodLocker nml(this);
1169
1170 {
1171 // Enter critical section. Does not block for safepoint.
1172 MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1173 // The caller can be calling the method statically or through an inline
1174 // cache call.
1175 if (!is_not_entrant()) {
1176 NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1177 SharedRuntime::get_handle_wrong_method_stub());
1178 assert (NativeJump::instruction_size == nmethod::_zombie_instruction_size, "");
1179 }
1180
1181 // When the nmethod becomes zombie it is no longer alive so the
1182 // dependencies must be flushed. nmethods in the not_entrant
1183 // state will be flushed later when the transition to zombie
1184 // happens or they get unloaded.
1185 if (state == zombie) {
1186 assert(SafepointSynchronize::is_at_safepoint(), "must be done at safepoint");
1187 flush_dependencies(NULL);
1188 } else {
1189 assert(state == not_entrant, "other cases may need to be handled differently");
1190 }
1191
1192 // Change state
1193 flags.state = state;
1194 } // leave critical region under Patching_lock
1195
1196 if (state == not_entrant) {
1197 Events::log("Make nmethod not entrant " INTPTR_FORMAT, this);
1198 } else {
1199 Events::log("Make nmethod zombie " INTPTR_FORMAT, this);
1200 }
1201
1202 if (TraceCreateZombies) {
1203 tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1204 }
1205
1206 // Make sweeper aware that there is a zombie method that needs to be removed
1207 NMethodSweeper::notify(this);
1208
1209 // not_entrant only stuff
1210 if (state == not_entrant) {
1211 mark_as_seen_on_stack();
1212 }
1213
1214 // It's a true state change, so mark the method as decompiled.
1215 inc_decompile_count();
1216
1217
1218 // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload event
1219 // and it hasn't already been reported for this nmethod then report it now.
1220 // (the event may have been reported earilier if the GC marked it for unloading).
1221 if (state == zombie) {
1222
1223 DTRACE_METHOD_UNLOAD_PROBE(method());
1224
1225 if (JvmtiExport::should_post_compiled_method_unload() &&
1226 !unload_reported()) {
1227 assert(method() != NULL, "checking");
1228 {
1229 HandleMark hm;
1230 JvmtiExport::post_compiled_method_unload_at_safepoint(
1231 method()->jmethod_id(), code_begin());
1232 }
1233 set_unload_reported();
1234 }
1235 }
1236
1237
1238 // Zombie only stuff
1239 if (state == zombie) {
1240 VTune::delete_nmethod(this);
1241 }
1242
1243 // Check whether method got unloaded at a safepoint before this,
1244 // if so we can skip the flushing steps below
1245 if (method() == NULL) return;
1246
1247 // Remove nmethod from method.
1248 // We need to check if both the _code and _from_compiled_code_entry_point
1249 // refer to this nmethod because there is a race in setting these two fields
1250 // in methodOop as seen in bugid 4947125.
1251 // If the vep() points to the zombie nmethod, the memory for the nmethod
1252 // could be flushed and the compiler and vtable stubs could still call
1253 // through it.
1254 if (method()->code() == this ||
1255 method()->from_compiled_entry() == verified_entry_point()) {
1256 HandleMark hm;
1257 method()->clear_code();
1258 }
1259 }
1260
1261
1262 #ifndef PRODUCT
1263 void nmethod::check_safepoint() {
1264 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1265 }
1266 #endif
1267
1268
1269 void nmethod::flush() {
1270 // Note that there are no valid oops in the nmethod anymore.
1271 assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1272 assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1273
1274 assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1275 check_safepoint();
1276
1277 // completely deallocate this method
1278 EventMark m("flushing nmethod " INTPTR_FORMAT " %s", this, "");
1279 if (PrintMethodFlushing) {
1280 tty->print_cr("*flushing nmethod " INTPTR_FORMAT ". Live blobs: %d", this, CodeCache::nof_blobs());
1281 }
1282
1283 // We need to deallocate any ExceptionCache data.
1284 // Note that we do not need to grab the nmethod lock for this, it
1285 // better be thread safe if we're disposing of it!
1286 ExceptionCache* ec = exception_cache();
1287 set_exception_cache(NULL);
1288 while(ec != NULL) {
1289 ExceptionCache* next = ec->next();
1290 delete ec;
1291 ec = next;
1292 }
1293
1294 ((CodeBlob*)(this))->flush();
1295
1296 CodeCache::free(this);
1297 }
1298
1299
1300 //
1301 // Notify all classes this nmethod is dependent on that it is no
1302 // longer dependent. This should only be called in two situations.
1303 // First, when a nmethod transitions to a zombie all dependents need
1304 // to be clear. Since zombification happens at a safepoint there's no
1305 // synchronization issues. The second place is a little more tricky.
1306 // During phase 1 of mark sweep class unloading may happen and as a
1307 // result some nmethods may get unloaded. In this case the flushing
1308 // of dependencies must happen during phase 1 since after GC any
1309 // dependencies in the unloaded nmethod won't be updated, so
1310 // traversing the dependency information in unsafe. In that case this
1311 // function is called with a non-NULL argument and this function only
1312 // notifies instanceKlasses that are reachable
1313
1314 void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1315 assert(SafepointSynchronize::is_at_safepoint(), "must be done at safepoint");
1316 assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1317 "is_alive is non-NULL if and only if we are called during GC");
1318 if (!has_flushed_dependencies()) {
1319 set_has_flushed_dependencies();
1320 for (Dependencies::DepStream deps(this); deps.next(); ) {
1321 klassOop klass = deps.context_type();
1322 if (klass == NULL) continue; // ignore things like evol_method
1323
1324 // During GC the is_alive closure is non-NULL, and is used to
1325 // determine liveness of dependees that need to be updated.
1326 if (is_alive == NULL || is_alive->do_object_b(klass)) {
1327 instanceKlass::cast(klass)->remove_dependent_nmethod(this);
1328 }
1329 }
1330 }
1331 }
1332
1333
1334 // If this oop is not live, the nmethod can be unloaded.
1335 bool nmethod::can_unload(BoolObjectClosure* is_alive,
1336 OopClosure* keep_alive,
1337 oop* root, bool unloading_occurred) {
1338 assert(root != NULL, "just checking");
1339 oop obj = *root;
1340 if (obj == NULL || is_alive->do_object_b(obj)) {
1341 return false;
1342 }
1343 if (obj->is_compiledICHolder()) {
1344 compiledICHolderOop cichk_oop = compiledICHolderOop(obj);
1345 if (is_alive->do_object_b(
1346 cichk_oop->holder_method()->method_holder()) &&
1347 is_alive->do_object_b(cichk_oop->holder_klass())) {
1348 // The oop should be kept alive
1349 keep_alive->do_oop(root);
1350 return false;
1351 }
1352 }
1353 assert(unloading_occurred, "Inconsistency in unloading");
1354 make_unloaded(is_alive, obj);
1355 return true;
1356 }
1357
1358 // ------------------------------------------------------------------
1359 // post_compiled_method_load_event
1360 // new method for install_code() path
1361 // Transfer information from compilation to jvmti
1362 void nmethod::post_compiled_method_load_event() {
1363
1364 methodOop moop = method();
1365 HS_DTRACE_PROBE8(hotspot, compiled__method__load,
1366 moop->klass_name()->bytes(),
1367 moop->klass_name()->utf8_length(),
1368 moop->name()->bytes(),
1369 moop->name()->utf8_length(),
1370 moop->signature()->bytes(),
1371 moop->signature()->utf8_length(),
1372 code_begin(), code_size());
1373
1374 if (JvmtiExport::should_post_compiled_method_load()) {
1375 JvmtiExport::post_compiled_method_load(this);
1376 }
1377 }
1378
1379 void nmethod::post_compiled_method_unload() {
1380 assert(_method != NULL && !is_unloaded(), "just checking");
1381 DTRACE_METHOD_UNLOAD_PROBE(method());
1382
1383 // If a JVMTI agent has enabled the CompiledMethodUnload event then
1384 // post the event. Sometime later this nmethod will be made a zombie by
1385 // the sweeper but the methodOop will not be valid at that point.
1386 if (JvmtiExport::should_post_compiled_method_unload()) {
1387 assert(!unload_reported(), "already unloaded");
1388 HandleMark hm;
1389 JvmtiExport::post_compiled_method_unload_at_safepoint(
1390 method()->jmethod_id(), code_begin());
1391 }
1392
1393 // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1394 // any time. As the nmethod is being unloaded now we mark it has
1395 // having the unload event reported - this will ensure that we don't
1396 // attempt to report the event in the unlikely scenario where the
1397 // event is enabled at the time the nmethod is made a zombie.
1398 set_unload_reported();
1399 }
1400
1401 // This is called at the end of the strong tracing/marking phase of a
1402 // GC to unload an nmethod if it contains otherwise unreachable
1403 // oops.
1404
1405 void nmethod::do_unloading(BoolObjectClosure* is_alive,
1406 OopClosure* keep_alive, bool unloading_occurred) {
1407 // Make sure the oop's ready to receive visitors
1408 assert(!is_zombie() && !is_unloaded(),
1409 "should not call follow on zombie or unloaded nmethod");
1410
1411 // If the method is not entrant then a JMP is plastered over the
1412 // first few bytes. If an oop in the old code was there, that oop
1413 // should not get GC'd. Skip the first few bytes of oops on
1414 // not-entrant methods.
1415 address low_boundary = verified_entry_point();
1416 if (is_not_entrant()) {
1417 low_boundary += NativeJump::instruction_size;
1418 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1419 // (See comment above.)
1420 }
1421
1422 // The RedefineClasses() API can cause the class unloading invariant
1423 // to no longer be true. See jvmtiExport.hpp for details.
1424 // Also, leave a debugging breadcrumb in local flag.
1425 bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1426 if (a_class_was_redefined) {
1427 // This set of the unloading_occurred flag is done before the
1428 // call to post_compiled_method_unload() so that the unloading
1429 // of this nmethod is reported.
1430 unloading_occurred = true;
1431 }
1432
1433 // Follow methodOop
1434 if (can_unload(is_alive, keep_alive, (oop*)&_method, unloading_occurred)) {
1435 return;
1436 }
1437
1438 // Exception cache
1439 ExceptionCache* ec = exception_cache();
1440 while (ec != NULL) {
1441 oop* ex_addr = (oop*)ec->exception_type_addr();
1442 oop ex = *ex_addr;
1443 ExceptionCache* next_ec = ec->next();
1444 if (ex != NULL && !is_alive->do_object_b(ex)) {
1445 assert(!ex->is_compiledICHolder(), "Possible error here");
1446 remove_from_exception_cache(ec);
1447 }
1448 ec = next_ec;
1449 }
1450
1451 // If class unloading occurred we first iterate over all inline caches and
1452 // clear ICs where the cached oop is referring to an unloaded klass or method.
1453 // The remaining live cached oops will be traversed in the relocInfo::oop_type
1454 // iteration below.
1455 if (unloading_occurred) {
1456 RelocIterator iter(this, low_boundary);
1457 while(iter.next()) {
1458 if (iter.type() == relocInfo::virtual_call_type) {
1459 CompiledIC *ic = CompiledIC_at(iter.reloc());
1460 oop ic_oop = ic->cached_oop();
1461 if (ic_oop != NULL && !is_alive->do_object_b(ic_oop)) {
1462 // The only exception is compiledICHolder oops which may
1463 // yet be marked below. (We check this further below).
1464 if (ic_oop->is_compiledICHolder()) {
1465 compiledICHolderOop cichk_oop = compiledICHolderOop(ic_oop);
1466 if (is_alive->do_object_b(
1467 cichk_oop->holder_method()->method_holder()) &&
1468 is_alive->do_object_b(cichk_oop->holder_klass())) {
1469 continue;
1470 }
1471 }
1472 ic->set_to_clean();
1473 assert(ic->cached_oop() == NULL, "cached oop in IC should be cleared")
1474 }
1475 }
1476 }
1477 }
1478
1479 // Compiled code
1480 RelocIterator iter(this, low_boundary);
1481 while (iter.next()) {
1482 if (iter.type() == relocInfo::oop_type) {
1483 oop_Relocation* r = iter.oop_reloc();
1484 // In this loop, we must only traverse those oops directly embedded in
1485 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1486 assert(1 == (r->oop_is_immediate()) +
1487 (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1488 "oop must be found in exactly one place");
1489 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1490 if (can_unload(is_alive, keep_alive, r->oop_addr(), unloading_occurred)) {
1491 return;
1492 }
1493 }
1494 }
1495 }
1496
1497
1498 // Scopes
1499 for (oop* p = oops_begin(); p < oops_end(); p++) {
1500 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1501 if (can_unload(is_alive, keep_alive, p, unloading_occurred)) {
1502 return;
1503 }
1504 }
1505
1506 #ifndef PRODUCT
1507 // This nmethod was not unloaded; check below that all CompiledICs
1508 // refer to marked oops.
1509 {
1510 RelocIterator iter(this, low_boundary);
1511 while (iter.next()) {
1512 if (iter.type() == relocInfo::virtual_call_type) {
1513 CompiledIC *ic = CompiledIC_at(iter.reloc());
1514 oop ic_oop = ic->cached_oop();
1515 assert(ic_oop == NULL || is_alive->do_object_b(ic_oop),
1516 "Found unmarked ic_oop in reachable nmethod");
1517 }
1518 }
1519 }
1520 #endif // !PRODUCT
1521 }
1522
1523 void nmethod::oops_do(OopClosure* f) {
1524 // make sure the oops ready to receive visitors
1525 assert(!is_zombie() && !is_unloaded(),
1526 "should not call follow on zombie or unloaded nmethod");
1527
1528 // If the method is not entrant or zombie then a JMP is plastered over the
1529 // first few bytes. If an oop in the old code was there, that oop
1530 // should not get GC'd. Skip the first few bytes of oops on
1531 // not-entrant methods.
1532 address low_boundary = verified_entry_point();
1533 if (is_not_entrant()) {
1534 low_boundary += NativeJump::instruction_size;
1535 // %%% Note: On SPARC we patch only a 4-byte trap, not a full NativeJump.
1536 // (See comment above.)
1537 }
1538
1539 // Compiled code
1540 f->do_oop((oop*) &_method);
1541 ExceptionCache* ec = exception_cache();
1542 while(ec != NULL) {
1543 f->do_oop((oop*)ec->exception_type_addr());
1544 ec = ec->next();
1545 }
1546
1547 RelocIterator iter(this, low_boundary);
1548 while (iter.next()) {
1549 if (iter.type() == relocInfo::oop_type ) {
1550 oop_Relocation* r = iter.oop_reloc();
1551 // In this loop, we must only follow those oops directly embedded in
1552 // the code. Other oops (oop_index>0) are seen as part of scopes_oops.
1553 assert(1 == (r->oop_is_immediate()) + (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()), "oop must be found in exactly one place");
1554 if (r->oop_is_immediate() && r->oop_value() != NULL) {
1555 f->do_oop(r->oop_addr());
1556 }
1557 }
1558 }
1559
1560 // Scopes
1561 for (oop* p = oops_begin(); p < oops_end(); p++) {
1562 if (*p == Universe::non_oop_word()) continue; // skip non-oops
1563 f->do_oop(p);
1564 }
1565 }
1566
1567 // Method that knows how to preserve outgoing arguments at call. This method must be
1568 // called with a frame corresponding to a Java invoke
1569 void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1570 if (!method()->is_native()) {
1571 SimpleScopeDesc ssd(this, fr.pc());
1572 Bytecode_invoke* call = Bytecode_invoke_at(ssd.method(), ssd.bci());
1573 bool is_static = call->is_invokestatic();
1574 symbolOop signature = call->signature();
1575 fr.oops_compiled_arguments_do(signature, is_static, reg_map, f);
1576 }
1577 }
1578
1579
1580 oop nmethod::embeddedOop_at(u_char* p) {
1581 RelocIterator iter(this, p, p + oopSize);
1582 while (iter.next())
1583 if (iter.type() == relocInfo::oop_type) {
1584 return iter.oop_reloc()->oop_value();
1585 }
1586 return NULL;
1587 }
1588
1589
1590 inline bool includes(void* p, void* from, void* to) {
1591 return from <= p && p < to;
1592 }
1593
1594
1595 void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1596 assert(count >= 2, "must be sentinel values, at least");
1597
1598 #ifdef ASSERT
1599 // must be sorted and unique; we do a binary search in find_pc_desc()
1600 int prev_offset = pcs[0].pc_offset();
1601 assert(prev_offset == PcDesc::lower_offset_limit,
1602 "must start with a sentinel");
1603 for (int i = 1; i < count; i++) {
1604 int this_offset = pcs[i].pc_offset();
1605 assert(this_offset > prev_offset, "offsets must be sorted");
1606 prev_offset = this_offset;
1607 }
1608 assert(prev_offset == PcDesc::upper_offset_limit,
1609 "must end with a sentinel");
1610 #endif //ASSERT
1611
1612 int size = count * sizeof(PcDesc);
1613 assert(scopes_pcs_size() >= size, "oob");
1614 memcpy(scopes_pcs_begin(), pcs, size);
1615
1616 // Adjust the final sentinel downward.
1617 PcDesc* last_pc = &scopes_pcs_begin()[count-1];
1618 assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
1619 last_pc->set_pc_offset(instructions_size() + 1);
1620 for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
1621 // Fill any rounding gaps with copies of the last record.
1622 last_pc[1] = last_pc[0];
1623 }
1624 // The following assert could fail if sizeof(PcDesc) is not
1625 // an integral multiple of oopSize (the rounding term).
1626 // If it fails, change the logic to always allocate a multiple
1627 // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
1628 assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
1629 }
1630
1631 void nmethod::copy_scopes_data(u_char* buffer, int size) {
1632 assert(scopes_data_size() >= size, "oob");
1633 memcpy(scopes_data_begin(), buffer, size);
1634 }
1635
1636
1637 #ifdef ASSERT
1638 static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
1639 PcDesc* lower = nm->scopes_pcs_begin();
1640 PcDesc* upper = nm->scopes_pcs_end();
1641 lower += 1; // exclude initial sentinel
1642 PcDesc* res = NULL;
1643 for (PcDesc* p = lower; p < upper; p++) {
1644 NOT_PRODUCT(--nmethod_stats.pc_desc_tests); // don't count this call to match_desc
1645 if (match_desc(p, pc_offset, approximate)) {
1646 if (res == NULL)
1647 res = p;
1648 else
1649 res = (PcDesc*) badAddress;
1650 }
1651 }
1652 return res;
1653 }
1654 #endif
1655
1656
1657 // Finds a PcDesc with real-pc equal to "pc"
1658 PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
1659 address base_address = instructions_begin();
1660 if ((pc < base_address) ||
1661 (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
1662 return NULL; // PC is wildly out of range
1663 }
1664 int pc_offset = (int) (pc - base_address);
1665
1666 // Check the PcDesc cache if it contains the desired PcDesc
1667 // (This as an almost 100% hit rate.)
1668 PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
1669 if (res != NULL) {
1670 assert(res == linear_search(this, pc_offset, approximate), "cache ok");
1671 return res;
1672 }
1673
1674 // Fallback algorithm: quasi-linear search for the PcDesc
1675 // Find the last pc_offset less than the given offset.
1676 // The successor must be the required match, if there is a match at all.
1677 // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
1678 PcDesc* lower = scopes_pcs_begin();
1679 PcDesc* upper = scopes_pcs_end();
1680 upper -= 1; // exclude final sentinel
1681 if (lower >= upper) return NULL; // native method; no PcDescs at all
1682
1683 #define assert_LU_OK \
1684 /* invariant on lower..upper during the following search: */ \
1685 assert(lower->pc_offset() < pc_offset, "sanity"); \
1686 assert(upper->pc_offset() >= pc_offset, "sanity")
1687 assert_LU_OK;
1688
1689 // Use the last successful return as a split point.
1690 PcDesc* mid = _pc_desc_cache.last_pc_desc();
1691 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
1692 if (mid->pc_offset() < pc_offset) {
1693 lower = mid;
1694 } else {
1695 upper = mid;
1696 }
1697
1698 // Take giant steps at first (4096, then 256, then 16, then 1)
1699 const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
1700 const int RADIX = (1 << LOG2_RADIX);
1701 for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
1702 while ((mid = lower + step) < upper) {
1703 assert_LU_OK;
1704 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
1705 if (mid->pc_offset() < pc_offset) {
1706 lower = mid;
1707 } else {
1708 upper = mid;
1709 break;
1710 }
1711 }
1712 assert_LU_OK;
1713 }
1714
1715 // Sneak up on the value with a linear search of length ~16.
1716 while (true) {
1717 assert_LU_OK;
1718 mid = lower + 1;
1719 NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
1720 if (mid->pc_offset() < pc_offset) {
1721 lower = mid;
1722 } else {
1723 upper = mid;
1724 break;
1725 }
1726 }
1727 #undef assert_LU_OK
1728
1729 if (match_desc(upper, pc_offset, approximate)) {
1730 assert(upper == linear_search(this, pc_offset, approximate), "search ok");
1731 _pc_desc_cache.add_pc_desc(upper);
1732 return upper;
1733 } else {
1734 assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
1735 return NULL;
1736 }
1737 }
1738
1739
1740 bool nmethod::check_all_dependencies() {
1741 bool found_check = false;
1742 // wholesale check of all dependencies
1743 for (Dependencies::DepStream deps(this); deps.next(); ) {
1744 if (deps.check_dependency() != NULL) {
1745 found_check = true;
1746 NOT_DEBUG(break);
1747 }
1748 }
1749 return found_check; // tell caller if we found anything
1750 }
1751
1752 bool nmethod::check_dependency_on(DepChange& changes) {
1753 // What has happened:
1754 // 1) a new class dependee has been added
1755 // 2) dependee and all its super classes have been marked
1756 bool found_check = false; // set true if we are upset
1757 for (Dependencies::DepStream deps(this); deps.next(); ) {
1758 // Evaluate only relevant dependencies.
1759 if (deps.spot_check_dependency_at(changes) != NULL) {
1760 found_check = true;
1761 NOT_DEBUG(break);
1762 }
1763 }
1764 return found_check;
1765 }
1766
1767 bool nmethod::is_evol_dependent_on(klassOop dependee) {
1768 instanceKlass *dependee_ik = instanceKlass::cast(dependee);
1769 objArrayOop dependee_methods = dependee_ik->methods();
1770 for (Dependencies::DepStream deps(this); deps.next(); ) {
1771 if (deps.type() == Dependencies::evol_method) {
1772 methodOop method = deps.method_argument(0);
1773 for (int j = 0; j < dependee_methods->length(); j++) {
1774 if ((methodOop) dependee_methods->obj_at(j) == method) {
1775 // RC_TRACE macro has an embedded ResourceMark
1776 RC_TRACE(0x01000000,
1777 ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
1778 _method->method_holder()->klass_part()->external_name(),
1779 _method->name()->as_C_string(),
1780 _method->signature()->as_C_string(), compile_id(),
1781 method->method_holder()->klass_part()->external_name(),
1782 method->name()->as_C_string(),
1783 method->signature()->as_C_string()));
1784 if (TraceDependencies || LogCompilation)
1785 deps.log_dependency(dependee);
1786 return true;
1787 }
1788 }
1789 }
1790 }
1791 return false;
1792 }
1793
1794 // Called from mark_for_deoptimization, when dependee is invalidated.
1795 bool nmethod::is_dependent_on_method(methodOop dependee) {
1796 for (Dependencies::DepStream deps(this); deps.next(); ) {
1797 if (deps.type() != Dependencies::evol_method)
1798 continue;
1799 methodOop method = deps.method_argument(0);
1800 if (method == dependee) return true;
1801 }
1802 return false;
1803 }
1804
1805
1806 bool nmethod::is_patchable_at(address instr_addr) {
1807 assert (code_contains(instr_addr), "wrong nmethod used");
1808 if (is_zombie()) {
1809 // a zombie may never be patched
1810 return false;
1811 }
1812 return true;
1813 }
1814
1815
1816 address nmethod::continuation_for_implicit_exception(address pc) {
1817 // Exception happened outside inline-cache check code => we are inside
1818 // an active nmethod => use cpc to determine a return address
1819 int exception_offset = pc - instructions_begin();
1820 int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
1821 #ifdef ASSERT
1822 if (cont_offset == 0) {
1823 Thread* thread = ThreadLocalStorage::get_thread_slow();
1824 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
1825 HandleMark hm(thread);
1826 ResourceMark rm(thread);
1827 CodeBlob* cb = CodeCache::find_blob(pc);
1828 assert(cb != NULL && cb == this, "");
1829 tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
1830 print();
1831 method()->print_codes();
1832 print_code();
1833 print_pcs();
1834 }
1835 #endif
1836 guarantee(cont_offset != 0, "unhandled implicit exception in compiled code");
1837 return instructions_begin() + cont_offset;
1838 }
1839
1840
1841
1842 void nmethod_init() {
1843 // make sure you didn't forget to adjust the filler fields
1844 assert(sizeof(nmFlags) <= 4, "nmFlags occupies more than a word");
1845 assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
1846 }
1847
1848
1849 //-------------------------------------------------------------------------------------------
1850
1851
1852 // QQQ might we make this work from a frame??
1853 nmethodLocker::nmethodLocker(address pc) {
1854 CodeBlob* cb = CodeCache::find_blob(pc);
1855 guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
1856 _nm = (nmethod*)cb;
1857 lock_nmethod(_nm);
1858 }
1859
1860 void nmethodLocker::lock_nmethod(nmethod* nm) {
1861 if (nm == NULL) return;
1862 Atomic::inc(&nm->_lock_count);
1863 guarantee(!nm->is_zombie(), "cannot lock a zombie method");
1864 }
1865
1866 void nmethodLocker::unlock_nmethod(nmethod* nm) {
1867 if (nm == NULL) return;
1868 Atomic::dec(&nm->_lock_count);
1869 guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
1870 }
1871
1872 bool nmethod::is_deopt_pc(address pc) {
1873 bool ret = pc == deopt_handler_begin();
1874 return ret;
1875 }
1876
1877
1878 // -----------------------------------------------------------------------------
1879 // Verification
1880
1881 void nmethod::verify() {
1882
1883 // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
1884 // seems odd.
1885
1886 if( is_zombie() || is_not_entrant() )
1887 return;
1888
1889 // Make sure all the entry points are correctly aligned for patching.
1890 NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
1891
1892 assert(method()->is_oop(), "must be valid");
1893
1894 ResourceMark rm;
1895
1896 if (!CodeCache::contains(this)) {
1897 fatal1("nmethod at " INTPTR_FORMAT " not in zone", this);
1898 }
1899
1900 if(is_native_method() )
1901 return;
1902
1903 nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
1904 if (nm != this) {
1905 fatal1("findNMethod did not find this nmethod (" INTPTR_FORMAT ")", this);
1906 }
1907
1908 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
1909 if (! p->verify(this)) {
1910 tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
1911 }
1912 }
1913
1914 verify_scopes();
1915 }
1916
1917
1918 void nmethod::verify_interrupt_point(address call_site) {
1919 // This code does not work in release mode since
1920 // owns_lock only is available in debug mode.
1921 CompiledIC* ic = NULL;
1922 Thread *cur = Thread::current();
1923 if (CompiledIC_lock->owner() == cur ||
1924 ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
1925 SafepointSynchronize::is_at_safepoint())) {
1926 ic = CompiledIC_at(call_site);
1927 CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
1928 } else {
1929 MutexLocker ml_verify (CompiledIC_lock);
1930 ic = CompiledIC_at(call_site);
1931 }
1932 PcDesc* pd = pc_desc_at(ic->end_of_call());
1933 assert(pd != NULL, "PcDesc must exist");
1934 for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
1935 pd->obj_decode_offset(), pd->should_reexecute());
1936 !sd->is_top(); sd = sd->sender()) {
1937 sd->verify();
1938 }
1939 }
1940
1941 void nmethod::verify_scopes() {
1942 if( !method() ) return; // Runtime stubs have no scope
1943 if (method()->is_native()) return; // Ignore stub methods.
1944 // iterate through all interrupt point
1945 // and verify the debug information is valid.
1946 RelocIterator iter((nmethod*)this);
1947 while (iter.next()) {
1948 address stub = NULL;
1949 switch (iter.type()) {
1950 case relocInfo::virtual_call_type:
1951 verify_interrupt_point(iter.addr());
1952 break;
1953 case relocInfo::opt_virtual_call_type:
1954 stub = iter.opt_virtual_call_reloc()->static_stub();
1955 verify_interrupt_point(iter.addr());
1956 break;
1957 case relocInfo::static_call_type:
1958 stub = iter.static_call_reloc()->static_stub();
1959 //verify_interrupt_point(iter.addr());
1960 break;
1961 case relocInfo::runtime_call_type:
1962 address destination = iter.reloc()->value();
1963 // Right now there is no way to find out which entries support
1964 // an interrupt point. It would be nice if we had this
1965 // information in a table.
1966 break;
1967 }
1968 assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
1969 }
1970 }
1971
1972
1973 // -----------------------------------------------------------------------------
1974 // Non-product code
1975 #ifndef PRODUCT
1976
1977 void nmethod::check_store() {
1978 // Make sure all oops in the compiled code are tenured
1979
1980 RelocIterator iter(this);
1981 while (iter.next()) {
1982 if (iter.type() == relocInfo::oop_type) {
1983 oop_Relocation* reloc = iter.oop_reloc();
1984 oop obj = reloc->oop_value();
1985 if (obj != NULL && !obj->is_perm()) {
1986 fatal("must be permanent oop in compiled code");
1987 }
1988 }
1989 }
1990 }
1991
1992 #endif // PRODUCT
1993
1994 // Printing operations
1995
1996 void nmethod::print() const {
1997 ResourceMark rm;
1998 ttyLocker ttyl; // keep the following output all in one block
1999
2000 tty->print("Compiled ");
2001
2002 if (is_compiled_by_c1()) {
2003 tty->print("(c1) ");
2004 } else if (is_compiled_by_c2()) {
2005 tty->print("(c2) ");
2006 } else {
2007 tty->print("(nm) ");
2008 }
2009
2010 print_on(tty, "nmethod");
2011 tty->cr();
2012 if (WizardMode) {
2013 tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2014 tty->print(" for method " INTPTR_FORMAT , (address)method());
2015 tty->print(" { ");
2016 if (version()) tty->print("v%d ", version());
2017 if (level()) tty->print("l%d ", level());
2018 if (is_in_use()) tty->print("in_use ");
2019 if (is_not_entrant()) tty->print("not_entrant ");
2020 if (is_zombie()) tty->print("zombie ");
2021 if (is_unloaded()) tty->print("unloaded ");
2022 tty->print_cr("}:");
2023 }
2024 if (size () > 0) tty->print_cr(" total in heap [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2025 (address)this,
2026 (address)this + size(),
2027 size());
2028 if (relocation_size () > 0) tty->print_cr(" relocation [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2029 relocation_begin(),
2030 relocation_end(),
2031 relocation_size());
2032 if (code_size () > 0) tty->print_cr(" main code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2033 code_begin(),
2034 code_end(),
2035 code_size());
2036 if (stub_size () > 0) tty->print_cr(" stub code [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2037 stub_begin(),
2038 stub_end(),
2039 stub_size());
2040 if (consts_size () > 0) tty->print_cr(" constants [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2041 consts_begin(),
2042 consts_end(),
2043 consts_size());
2044 if (scopes_data_size () > 0) tty->print_cr(" scopes data [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2045 scopes_data_begin(),
2046 scopes_data_end(),
2047 scopes_data_size());
2048 if (scopes_pcs_size () > 0) tty->print_cr(" scopes pcs [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2049 scopes_pcs_begin(),
2050 scopes_pcs_end(),
2051 scopes_pcs_size());
2052 if (dependencies_size () > 0) tty->print_cr(" dependencies [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2053 dependencies_begin(),
2054 dependencies_end(),
2055 dependencies_size());
2056 if (handler_table_size() > 0) tty->print_cr(" handler table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2057 handler_table_begin(),
2058 handler_table_end(),
2059 handler_table_size());
2060 if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2061 nul_chk_table_begin(),
2062 nul_chk_table_end(),
2063 nul_chk_table_size());
2064 if (oops_size () > 0) tty->print_cr(" oops [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2065 oops_begin(),
2066 oops_end(),
2067 oops_size());
2068 }
2069
2070 void nmethod::print_code() {
2071 HandleMark hm;
2072 ResourceMark m;
2073 Disassembler::decode(this);
2074 }
2075
2076
2077 #ifndef PRODUCT
2078
2079 void nmethod::print_scopes() {
2080 // Find the first pc desc for all scopes in the code and print it.
2081 ResourceMark rm;
2082 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2083 if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2084 continue;
2085
2086 ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2087 sd->print_on(tty, p);
2088 }
2089 }
2090
2091 void nmethod::print_dependencies() {
2092 ResourceMark rm;
2093 ttyLocker ttyl; // keep the following output all in one block
2094 tty->print_cr("Dependencies:");
2095 for (Dependencies::DepStream deps(this); deps.next(); ) {
2096 deps.print_dependency();
2097 klassOop ctxk = deps.context_type();
2098 if (ctxk != NULL) {
2099 Klass* k = Klass::cast(ctxk);
2100 if (k->oop_is_instance() && ((instanceKlass*)k)->is_dependent_nmethod(this)) {
2101 tty->print_cr(" [nmethod<=klass]%s", k->external_name());
2102 }
2103 }
2104 deps.log_dependency(); // put it into the xml log also
2105 }
2106 }
2107
2108
2109 void nmethod::print_relocations() {
2110 ResourceMark m; // in case methods get printed via the debugger
2111 tty->print_cr("relocations:");
2112 RelocIterator iter(this);
2113 iter.print();
2114 if (UseRelocIndex) {
2115 jint* index_end = (jint*)relocation_end() - 1;
2116 jint index_size = *index_end;
2117 jint* index_start = (jint*)( (address)index_end - index_size );
2118 tty->print_cr(" index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2119 if (index_size > 0) {
2120 jint* ip;
2121 for (ip = index_start; ip+2 <= index_end; ip += 2)
2122 tty->print_cr(" (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2123 ip[0],
2124 ip[1],
2125 header_end()+ip[0],
2126 relocation_begin()-1+ip[1]);
2127 for (; ip < index_end; ip++)
2128 tty->print_cr(" (%d ?)", ip[0]);
2129 tty->print_cr(" @" INTPTR_FORMAT ": index_size=%d", ip, *ip++);
2130 tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2131 }
2132 }
2133 }
2134
2135
2136 void nmethod::print_pcs() {
2137 ResourceMark m; // in case methods get printed via debugger
2138 tty->print_cr("pc-bytecode offsets:");
2139 for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2140 p->print(this);
2141 }
2142 }
2143
2144 #endif // PRODUCT
2145
2146 const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2147 RelocIterator iter(this, begin, end);
2148 bool have_one = false;
2149 while (iter.next()) {
2150 have_one = true;
2151 switch (iter.type()) {
2152 case relocInfo::none: return "no_reloc";
2153 case relocInfo::oop_type: {
2154 stringStream st;
2155 oop_Relocation* r = iter.oop_reloc();
2156 oop obj = r->oop_value();
2157 st.print("oop(");
2158 if (obj == NULL) st.print("NULL");
2159 else obj->print_value_on(&st);
2160 st.print(")");
2161 return st.as_string();
2162 }
2163 case relocInfo::virtual_call_type: return "virtual_call";
2164 case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2165 case relocInfo::static_call_type: return "static_call";
2166 case relocInfo::static_stub_type: return "static_stub";
2167 case relocInfo::runtime_call_type: return "runtime_call";
2168 case relocInfo::external_word_type: return "external_word";
2169 case relocInfo::internal_word_type: return "internal_word";
2170 case relocInfo::section_word_type: return "section_word";
2171 case relocInfo::poll_type: return "poll";
2172 case relocInfo::poll_return_type: return "poll_return";
2173 case relocInfo::type_mask: return "type_bit_mask";
2174 }
2175 }
2176 return have_one ? "other" : NULL;
2177 }
2178
2179 // Return a the last scope in (begin..end]
2180 ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2181 PcDesc* p = pc_desc_near(begin+1);
2182 if (p != NULL && p->real_pc(this) <= end) {
2183 return new ScopeDesc(this, p->scope_decode_offset(),
2184 p->obj_decode_offset(), p->should_reexecute());
2185 }
2186 return NULL;
2187 }
2188
2189 void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2190 // First, find an oopmap in (begin, end].
2191 // We use the odd half-closed interval so that oop maps and scope descs
2192 // which are tied to the byte after a call are printed with the call itself.
2193 address base = instructions_begin();
2194 OopMapSet* oms = oop_maps();
2195 if (oms != NULL) {
2196 for (int i = 0, imax = oms->size(); i < imax; i++) {
2197 OopMap* om = oms->at(i);
2198 address pc = base + om->offset();
2199 if (pc > begin) {
2200 if (pc <= end) {
2201 st->move_to(column);
2202 st->print("; ");
2203 om->print_on(st);
2204 }
2205 break;
2206 }
2207 }
2208 }
2209
2210 // Print any debug info present at this pc.
2211 ScopeDesc* sd = scope_desc_in(begin, end);
2212 if (sd != NULL) {
2213 st->move_to(column);
2214 if (sd->bci() == SynchronizationEntryBCI) {
2215 st->print(";*synchronization entry");
2216 } else {
2217 if (sd->method().is_null()) {
2218 st->print("method is NULL");
2219 } else if (sd->method()->is_native()) {
2220 st->print("method is native");
2221 } else {
2222 address bcp = sd->method()->bcp_from(sd->bci());
2223 Bytecodes::Code bc = Bytecodes::java_code_at(bcp);
2224 st->print(";*%s", Bytecodes::name(bc));
2225 switch (bc) {
2226 case Bytecodes::_invokevirtual:
2227 case Bytecodes::_invokespecial:
2228 case Bytecodes::_invokestatic:
2229 case Bytecodes::_invokeinterface:
2230 {
2231 Bytecode_invoke* invoke = Bytecode_invoke_at(sd->method(), sd->bci());
2232 st->print(" ");
2233 if (invoke->name() != NULL)
2234 invoke->name()->print_symbol_on(st);
2235 else
2236 st->print("<UNKNOWN>");
2237 break;
2238 }
2239 case Bytecodes::_getfield:
2240 case Bytecodes::_putfield:
2241 case Bytecodes::_getstatic:
2242 case Bytecodes::_putstatic:
2243 {
2244 methodHandle sdm = sd->method();
2245 Bytecode_field* field = Bytecode_field_at(sdm(), sdm->bcp_from(sd->bci()));
2246 constantPoolOop sdmc = sdm->constants();
2247 symbolOop name = sdmc->name_ref_at(field->index());
2248 st->print(" ");
2249 if (name != NULL)
2250 name->print_symbol_on(st);
2251 else
2252 st->print("<UNKNOWN>");
2253 }
2254 }
2255 }
2256 }
2257
2258 // Print all scopes
2259 for (;sd != NULL; sd = sd->sender()) {
2260 st->move_to(column);
2261 st->print("; -");
2262 if (sd->method().is_null()) {
2263 st->print("method is NULL");
2264 } else {
2265 sd->method()->print_short_name(st);
2266 }
2267 int lineno = sd->method()->line_number_from_bci(sd->bci());
2268 if (lineno != -1) {
2269 st->print("@%d (line %d)", sd->bci(), lineno);
2270 } else {
2271 st->print("@%d", sd->bci());
2272 }
2273 st->cr();
2274 }
2275 }
2276
2277 // Print relocation information
2278 const char* str = reloc_string_for(begin, end);
2279 if (str != NULL) {
2280 if (sd != NULL) st->cr();
2281 st->move_to(column);
2282 st->print("; {%s}", str);
2283 }
2284 int cont_offset = ImplicitExceptionTable(this).at(begin - instructions_begin());
2285 if (cont_offset != 0) {
2286 st->move_to(column);
2287 st->print("; implicit exception: dispatches to " INTPTR_FORMAT, instructions_begin() + cont_offset);
2288 }
2289
2290 }
2291
2292 #ifndef PRODUCT
2293
2294 void nmethod::print_value_on(outputStream* st) const {
2295 print_on(st, "nmethod");
2296 }
2297
2298 void nmethod::print_calls(outputStream* st) {
2299 RelocIterator iter(this);
2300 while (iter.next()) {
2301 switch (iter.type()) {
2302 case relocInfo::virtual_call_type:
2303 case relocInfo::opt_virtual_call_type: {
2304 VerifyMutexLocker mc(CompiledIC_lock);
2305 CompiledIC_at(iter.reloc())->print();
2306 break;
2307 }
2308 case relocInfo::static_call_type:
2309 st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2310 compiledStaticCall_at(iter.reloc())->print();
2311 break;
2312 }
2313 }
2314 }
2315
2316 void nmethod::print_handler_table() {
2317 ExceptionHandlerTable(this).print();
2318 }
2319
2320 void nmethod::print_nul_chk_table() {
2321 ImplicitExceptionTable(this).print(instructions_begin());
2322 }
2323
2324 void nmethod::print_statistics() {
2325 ttyLocker ttyl;
2326 if (xtty != NULL) xtty->head("statistics type='nmethod'");
2327 nmethod_stats.print_native_nmethod_stats();
2328 nmethod_stats.print_nmethod_stats();
2329 DebugInformationRecorder::print_statistics();
2330 nmethod_stats.print_pc_stats();
2331 Dependencies::print_statistics();
2332 if (xtty != NULL) xtty->tail("statistics");
2333 }
2334
2335 #endif // PRODUCT