nmethod.cpp revision 2767:436b4a3231bf
1/*
2 * Copyright (c) 1997, 2011, 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/methodDataOop.hpp"
38#include "prims/jvmtiRedefineClassesTrace.hpp"
39#include "prims/jvmtiImpl.hpp"
40#include "runtime/sharedRuntime.hpp"
41#include "runtime/sweeper.hpp"
42#include "utilities/dtrace.hpp"
43#include "utilities/events.hpp"
44#include "utilities/xmlstream.hpp"
45#ifdef SHARK
46#include "shark/sharkCompiler.hpp"
47#endif
48
49#ifdef DTRACE_ENABLED
50
51// Only bother with this argument setup if dtrace is available
52
53#ifndef USDT2
54HS_DTRACE_PROBE_DECL8(hotspot, compiled__method__load,
55  const char*, int, const char*, int, const char*, int, void*, size_t);
56
57HS_DTRACE_PROBE_DECL6(hotspot, compiled__method__unload,
58  char*, int, char*, int, char*, int);
59
60#define DTRACE_METHOD_UNLOAD_PROBE(method)                                \
61  {                                                                       \
62    methodOop m = (method);                                               \
63    if (m != NULL) {                                                      \
64      Symbol* klass_name = m->klass_name();                               \
65      Symbol* name = m->name();                                           \
66      Symbol* signature = m->signature();                                 \
67      HS_DTRACE_PROBE6(hotspot, compiled__method__unload,                 \
68        klass_name->bytes(), klass_name->utf8_length(),                   \
69        name->bytes(), name->utf8_length(),                               \
70        signature->bytes(), signature->utf8_length());                    \
71    }                                                                     \
72  }
73#else /* USDT2 */
74#define DTRACE_METHOD_UNLOAD_PROBE(method)                                \
75  {                                                                       \
76    methodOop m = (method);                                               \
77    if (m != NULL) {                                                      \
78      Symbol* klass_name = m->klass_name();                               \
79      Symbol* name = m->name();                                           \
80      Symbol* signature = m->signature();                                 \
81      HOTSPOT_COMPILED_METHOD_UNLOAD(                                     \
82        (char *) klass_name->bytes(), klass_name->utf8_length(),                   \
83        (char *) name->bytes(), name->utf8_length(),                               \
84        (char *) signature->bytes(), signature->utf8_length());                    \
85    }                                                                     \
86  }
87#endif /* USDT2 */
88
89#else //  ndef DTRACE_ENABLED
90
91#define DTRACE_METHOD_UNLOAD_PROBE(method)
92
93#endif
94
95bool nmethod::is_compiled_by_c1() const {
96  if (compiler() == NULL || method() == NULL)  return false;  // can happen during debug printing
97  if (is_native_method()) return false;
98  return compiler()->is_c1();
99}
100bool nmethod::is_compiled_by_c2() const {
101  if (compiler() == NULL || method() == NULL)  return false;  // can happen during debug printing
102  if (is_native_method()) return false;
103  return compiler()->is_c2();
104}
105bool nmethod::is_compiled_by_shark() const {
106  if (is_native_method()) return false;
107  assert(compiler() != NULL, "must be");
108  return compiler()->is_shark();
109}
110
111
112
113//---------------------------------------------------------------------------------
114// NMethod statistics
115// They are printed under various flags, including:
116//   PrintC1Statistics, PrintOptoStatistics, LogVMOutput, and LogCompilation.
117// (In the latter two cases, they like other stats are printed to the log only.)
118
119#ifndef PRODUCT
120// These variables are put into one block to reduce relocations
121// and make it simpler to print from the debugger.
122static
123struct nmethod_stats_struct {
124  int nmethod_count;
125  int total_size;
126  int relocation_size;
127  int consts_size;
128  int insts_size;
129  int stub_size;
130  int scopes_data_size;
131  int scopes_pcs_size;
132  int dependencies_size;
133  int handler_table_size;
134  int nul_chk_table_size;
135  int oops_size;
136
137  void note_nmethod(nmethod* nm) {
138    nmethod_count += 1;
139    total_size          += nm->size();
140    relocation_size     += nm->relocation_size();
141    consts_size         += nm->consts_size();
142    insts_size          += nm->insts_size();
143    stub_size           += nm->stub_size();
144    oops_size           += nm->oops_size();
145    scopes_data_size    += nm->scopes_data_size();
146    scopes_pcs_size     += nm->scopes_pcs_size();
147    dependencies_size   += nm->dependencies_size();
148    handler_table_size  += nm->handler_table_size();
149    nul_chk_table_size  += nm->nul_chk_table_size();
150  }
151  void print_nmethod_stats() {
152    if (nmethod_count == 0)  return;
153    tty->print_cr("Statistics for %d bytecoded nmethods:", nmethod_count);
154    if (total_size != 0)          tty->print_cr(" total in heap  = %d", total_size);
155    if (relocation_size != 0)     tty->print_cr(" relocation     = %d", relocation_size);
156    if (consts_size != 0)         tty->print_cr(" constants      = %d", consts_size);
157    if (insts_size != 0)          tty->print_cr(" main code      = %d", insts_size);
158    if (stub_size != 0)           tty->print_cr(" stub code      = %d", stub_size);
159    if (oops_size != 0)           tty->print_cr(" oops           = %d", oops_size);
160    if (scopes_data_size != 0)    tty->print_cr(" scopes data    = %d", scopes_data_size);
161    if (scopes_pcs_size != 0)     tty->print_cr(" scopes pcs     = %d", scopes_pcs_size);
162    if (dependencies_size != 0)   tty->print_cr(" dependencies   = %d", dependencies_size);
163    if (handler_table_size != 0)  tty->print_cr(" handler table  = %d", handler_table_size);
164    if (nul_chk_table_size != 0)  tty->print_cr(" nul chk table  = %d", nul_chk_table_size);
165  }
166
167  int native_nmethod_count;
168  int native_total_size;
169  int native_relocation_size;
170  int native_insts_size;
171  int native_oops_size;
172  void note_native_nmethod(nmethod* nm) {
173    native_nmethod_count += 1;
174    native_total_size       += nm->size();
175    native_relocation_size  += nm->relocation_size();
176    native_insts_size       += nm->insts_size();
177    native_oops_size        += nm->oops_size();
178  }
179  void print_native_nmethod_stats() {
180    if (native_nmethod_count == 0)  return;
181    tty->print_cr("Statistics for %d native nmethods:", native_nmethod_count);
182    if (native_total_size != 0)       tty->print_cr(" N. total size  = %d", native_total_size);
183    if (native_relocation_size != 0)  tty->print_cr(" N. relocation  = %d", native_relocation_size);
184    if (native_insts_size != 0)       tty->print_cr(" N. main code   = %d", native_insts_size);
185    if (native_oops_size != 0)        tty->print_cr(" N. oops        = %d", native_oops_size);
186  }
187
188  int pc_desc_resets;   // number of resets (= number of caches)
189  int pc_desc_queries;  // queries to nmethod::find_pc_desc
190  int pc_desc_approx;   // number of those which have approximate true
191  int pc_desc_repeats;  // number of _pc_descs[0] hits
192  int pc_desc_hits;     // number of LRU cache hits
193  int pc_desc_tests;    // total number of PcDesc examinations
194  int pc_desc_searches; // total number of quasi-binary search steps
195  int pc_desc_adds;     // number of LUR cache insertions
196
197  void print_pc_stats() {
198    tty->print_cr("PcDesc Statistics:  %d queries, %.2f comparisons per query",
199                  pc_desc_queries,
200                  (double)(pc_desc_tests + pc_desc_searches)
201                  / pc_desc_queries);
202    tty->print_cr("  caches=%d queries=%d/%d, hits=%d+%d, tests=%d+%d, adds=%d",
203                  pc_desc_resets,
204                  pc_desc_queries, pc_desc_approx,
205                  pc_desc_repeats, pc_desc_hits,
206                  pc_desc_tests, pc_desc_searches, pc_desc_adds);
207  }
208} nmethod_stats;
209#endif //PRODUCT
210
211
212//---------------------------------------------------------------------------------
213
214
215ExceptionCache::ExceptionCache(Handle exception, address pc, address handler) {
216  assert(pc != NULL, "Must be non null");
217  assert(exception.not_null(), "Must be non null");
218  assert(handler != NULL, "Must be non null");
219
220  _count = 0;
221  _exception_type = exception->klass();
222  _next = NULL;
223
224  add_address_and_handler(pc,handler);
225}
226
227
228address ExceptionCache::match(Handle exception, address pc) {
229  assert(pc != NULL,"Must be non null");
230  assert(exception.not_null(),"Must be non null");
231  if (exception->klass() == exception_type()) {
232    return (test_address(pc));
233  }
234
235  return NULL;
236}
237
238
239bool ExceptionCache::match_exception_with_space(Handle exception) {
240  assert(exception.not_null(),"Must be non null");
241  if (exception->klass() == exception_type() && count() < cache_size) {
242    return true;
243  }
244  return false;
245}
246
247
248address ExceptionCache::test_address(address addr) {
249  for (int i=0; i<count(); i++) {
250    if (pc_at(i) == addr) {
251      return handler_at(i);
252    }
253  }
254  return NULL;
255}
256
257
258bool ExceptionCache::add_address_and_handler(address addr, address handler) {
259  if (test_address(addr) == handler) return true;
260  if (count() < cache_size) {
261    set_pc_at(count(),addr);
262    set_handler_at(count(), handler);
263    increment_count();
264    return true;
265  }
266  return false;
267}
268
269
270// private method for handling exception cache
271// These methods are private, and used to manipulate the exception cache
272// directly.
273ExceptionCache* nmethod::exception_cache_entry_for_exception(Handle exception) {
274  ExceptionCache* ec = exception_cache();
275  while (ec != NULL) {
276    if (ec->match_exception_with_space(exception)) {
277      return ec;
278    }
279    ec = ec->next();
280  }
281  return NULL;
282}
283
284
285//-----------------------------------------------------------------------------
286
287
288// Helper used by both find_pc_desc methods.
289static inline bool match_desc(PcDesc* pc, int pc_offset, bool approximate) {
290  NOT_PRODUCT(++nmethod_stats.pc_desc_tests);
291  if (!approximate)
292    return pc->pc_offset() == pc_offset;
293  else
294    return (pc-1)->pc_offset() < pc_offset && pc_offset <= pc->pc_offset();
295}
296
297void PcDescCache::reset_to(PcDesc* initial_pc_desc) {
298  if (initial_pc_desc == NULL) {
299    _pc_descs[0] = NULL; // native method; no PcDescs at all
300    return;
301  }
302  NOT_PRODUCT(++nmethod_stats.pc_desc_resets);
303  // reset the cache by filling it with benign (non-null) values
304  assert(initial_pc_desc->pc_offset() < 0, "must be sentinel");
305  for (int i = 0; i < cache_size; i++)
306    _pc_descs[i] = initial_pc_desc;
307}
308
309PcDesc* PcDescCache::find_pc_desc(int pc_offset, bool approximate) {
310  NOT_PRODUCT(++nmethod_stats.pc_desc_queries);
311  NOT_PRODUCT(if (approximate) ++nmethod_stats.pc_desc_approx);
312
313  // Note: one might think that caching the most recently
314  // read value separately would be a win, but one would be
315  // wrong.  When many threads are updating it, the cache
316  // line it's in would bounce between caches, negating
317  // any benefit.
318
319  // In order to prevent race conditions do not load cache elements
320  // repeatedly, but use a local copy:
321  PcDesc* res;
322
323  // Step one:  Check the most recently added value.
324  res = _pc_descs[0];
325  if (res == NULL) return NULL;  // native method; no PcDescs at all
326  if (match_desc(res, pc_offset, approximate)) {
327    NOT_PRODUCT(++nmethod_stats.pc_desc_repeats);
328    return res;
329  }
330
331  // Step two:  Check the rest of the LRU cache.
332  for (int i = 1; i < cache_size; ++i) {
333    res = _pc_descs[i];
334    if (res->pc_offset() < 0) break;  // optimization: skip empty cache
335    if (match_desc(res, pc_offset, approximate)) {
336      NOT_PRODUCT(++nmethod_stats.pc_desc_hits);
337      return res;
338    }
339  }
340
341  // Report failure.
342  return NULL;
343}
344
345void PcDescCache::add_pc_desc(PcDesc* pc_desc) {
346  NOT_PRODUCT(++nmethod_stats.pc_desc_adds);
347  // Update the LRU cache by shifting pc_desc forward.
348  for (int i = 0; i < cache_size; i++)  {
349    PcDesc* next = _pc_descs[i];
350    _pc_descs[i] = pc_desc;
351    pc_desc = next;
352  }
353}
354
355// adjust pcs_size so that it is a multiple of both oopSize and
356// sizeof(PcDesc) (assumes that if sizeof(PcDesc) is not a multiple
357// of oopSize, then 2*sizeof(PcDesc) is)
358static int adjust_pcs_size(int pcs_size) {
359  int nsize = round_to(pcs_size,   oopSize);
360  if ((nsize % sizeof(PcDesc)) != 0) {
361    nsize = pcs_size + sizeof(PcDesc);
362  }
363  assert((nsize % oopSize) == 0, "correct alignment");
364  return nsize;
365}
366
367//-----------------------------------------------------------------------------
368
369
370void nmethod::add_exception_cache_entry(ExceptionCache* new_entry) {
371  assert(ExceptionCache_lock->owned_by_self(),"Must hold the ExceptionCache_lock");
372  assert(new_entry != NULL,"Must be non null");
373  assert(new_entry->next() == NULL, "Must be null");
374
375  if (exception_cache() != NULL) {
376    new_entry->set_next(exception_cache());
377  }
378  set_exception_cache(new_entry);
379}
380
381void nmethod::remove_from_exception_cache(ExceptionCache* ec) {
382  ExceptionCache* prev = NULL;
383  ExceptionCache* curr = exception_cache();
384  assert(curr != NULL, "nothing to remove");
385  // find the previous and next entry of ec
386  while (curr != ec) {
387    prev = curr;
388    curr = curr->next();
389    assert(curr != NULL, "ExceptionCache not found");
390  }
391  // now: curr == ec
392  ExceptionCache* next = curr->next();
393  if (prev == NULL) {
394    set_exception_cache(next);
395  } else {
396    prev->set_next(next);
397  }
398  delete curr;
399}
400
401
402// public method for accessing the exception cache
403// These are the public access methods.
404address nmethod::handler_for_exception_and_pc(Handle exception, address pc) {
405  // We never grab a lock to read the exception cache, so we may
406  // have false negatives. This is okay, as it can only happen during
407  // the first few exception lookups for a given nmethod.
408  ExceptionCache* ec = exception_cache();
409  while (ec != NULL) {
410    address ret_val;
411    if ((ret_val = ec->match(exception,pc)) != NULL) {
412      return ret_val;
413    }
414    ec = ec->next();
415  }
416  return NULL;
417}
418
419
420void nmethod::add_handler_for_exception_and_pc(Handle exception, address pc, address handler) {
421  // There are potential race conditions during exception cache updates, so we
422  // must own the ExceptionCache_lock before doing ANY modifications. Because
423  // we don't lock during reads, it is possible to have several threads attempt
424  // to update the cache with the same data. We need to check for already inserted
425  // copies of the current data before adding it.
426
427  MutexLocker ml(ExceptionCache_lock);
428  ExceptionCache* target_entry = exception_cache_entry_for_exception(exception);
429
430  if (target_entry == NULL || !target_entry->add_address_and_handler(pc,handler)) {
431    target_entry = new ExceptionCache(exception,pc,handler);
432    add_exception_cache_entry(target_entry);
433  }
434}
435
436
437//-------------end of code for ExceptionCache--------------
438
439
440int nmethod::total_size() const {
441  return
442    consts_size()        +
443    insts_size()         +
444    stub_size()          +
445    scopes_data_size()   +
446    scopes_pcs_size()    +
447    handler_table_size() +
448    nul_chk_table_size();
449}
450
451const char* nmethod::compile_kind() const {
452  if (is_osr_method())     return "osr";
453  if (method() != NULL && is_native_method())  return "c2n";
454  return NULL;
455}
456
457// Fill in default values for various flag fields
458void nmethod::init_defaults() {
459  _state                      = alive;
460  _marked_for_reclamation     = 0;
461  _has_flushed_dependencies   = 0;
462  _speculatively_disconnected = 0;
463  _has_unsafe_access          = 0;
464  _has_method_handle_invokes  = 0;
465  _marked_for_deoptimization  = 0;
466  _lock_count                 = 0;
467  _stack_traversal_mark       = 0;
468  _unload_reported            = false;           // jvmti state
469
470#ifdef ASSERT
471  _oops_are_stale             = false;
472#endif
473
474  _oops_do_mark_link       = NULL;
475  _jmethod_id              = NULL;
476  _osr_link                = NULL;
477  _scavenge_root_link      = NULL;
478  _scavenge_root_state     = 0;
479  _saved_nmethod_link      = NULL;
480  _compiler                = NULL;
481
482#ifdef HAVE_DTRACE_H
483  _trap_offset             = 0;
484#endif // def HAVE_DTRACE_H
485}
486
487
488nmethod* nmethod::new_native_nmethod(methodHandle method,
489  int compile_id,
490  CodeBuffer *code_buffer,
491  int vep_offset,
492  int frame_complete,
493  int frame_size,
494  ByteSize basic_lock_owner_sp_offset,
495  ByteSize basic_lock_sp_offset,
496  OopMapSet* oop_maps) {
497  // create nmethod
498  nmethod* nm = NULL;
499  {
500    MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
501    int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
502    CodeOffsets offsets;
503    offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
504    offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
505    nm = new (native_nmethod_size)
506      nmethod(method(), native_nmethod_size, compile_id, &offsets,
507              code_buffer, frame_size,
508              basic_lock_owner_sp_offset, basic_lock_sp_offset,
509              oop_maps);
510    NOT_PRODUCT(if (nm != NULL)  nmethod_stats.note_native_nmethod(nm));
511    if (PrintAssembly && nm != NULL)
512      Disassembler::decode(nm);
513  }
514  // verify nmethod
515  debug_only(if (nm) nm->verify();) // might block
516
517  if (nm != NULL) {
518    nm->log_new_nmethod();
519  }
520
521  return nm;
522}
523
524#ifdef HAVE_DTRACE_H
525nmethod* nmethod::new_dtrace_nmethod(methodHandle method,
526                                     CodeBuffer *code_buffer,
527                                     int vep_offset,
528                                     int trap_offset,
529                                     int frame_complete,
530                                     int frame_size) {
531  // create nmethod
532  nmethod* nm = NULL;
533  {
534    MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
535    int nmethod_size = allocation_size(code_buffer, sizeof(nmethod));
536    CodeOffsets offsets;
537    offsets.set_value(CodeOffsets::Verified_Entry, vep_offset);
538    offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset);
539    offsets.set_value(CodeOffsets::Frame_Complete, frame_complete);
540
541    nm = new (nmethod_size) nmethod(method(), nmethod_size, &offsets, code_buffer, frame_size);
542
543    NOT_PRODUCT(if (nm != NULL)  nmethod_stats.note_nmethod(nm));
544    if (PrintAssembly && nm != NULL)
545      Disassembler::decode(nm);
546  }
547  // verify nmethod
548  debug_only(if (nm) nm->verify();) // might block
549
550  if (nm != NULL) {
551    nm->log_new_nmethod();
552  }
553
554  return nm;
555}
556
557#endif // def HAVE_DTRACE_H
558
559nmethod* nmethod::new_nmethod(methodHandle method,
560  int compile_id,
561  int entry_bci,
562  CodeOffsets* offsets,
563  int orig_pc_offset,
564  DebugInformationRecorder* debug_info,
565  Dependencies* dependencies,
566  CodeBuffer* code_buffer, int frame_size,
567  OopMapSet* oop_maps,
568  ExceptionHandlerTable* handler_table,
569  ImplicitExceptionTable* nul_chk_table,
570  AbstractCompiler* compiler,
571  int comp_level
572)
573{
574  assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
575  // create nmethod
576  nmethod* nm = NULL;
577  { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
578    int nmethod_size =
579      allocation_size(code_buffer, sizeof(nmethod))
580      + adjust_pcs_size(debug_info->pcs_size())
581      + round_to(dependencies->size_in_bytes() , oopSize)
582      + round_to(handler_table->size_in_bytes(), oopSize)
583      + round_to(nul_chk_table->size_in_bytes(), oopSize)
584      + round_to(debug_info->data_size()       , oopSize);
585    nm = new (nmethod_size)
586      nmethod(method(), nmethod_size, compile_id, entry_bci, offsets,
587              orig_pc_offset, debug_info, dependencies, code_buffer, frame_size,
588              oop_maps,
589              handler_table,
590              nul_chk_table,
591              compiler,
592              comp_level);
593    if (nm != NULL) {
594      // To make dependency checking during class loading fast, record
595      // the nmethod dependencies in the classes it is dependent on.
596      // This allows the dependency checking code to simply walk the
597      // class hierarchy above the loaded class, checking only nmethods
598      // which are dependent on those classes.  The slow way is to
599      // check every nmethod for dependencies which makes it linear in
600      // the number of methods compiled.  For applications with a lot
601      // classes the slow way is too slow.
602      for (Dependencies::DepStream deps(nm); deps.next(); ) {
603        klassOop klass = deps.context_type();
604        if (klass == NULL)  continue;  // ignore things like evol_method
605
606        // record this nmethod as dependent on this klass
607        instanceKlass::cast(klass)->add_dependent_nmethod(nm);
608      }
609    }
610    NOT_PRODUCT(if (nm != NULL)  nmethod_stats.note_nmethod(nm));
611    if (PrintAssembly && nm != NULL)
612      Disassembler::decode(nm);
613  }
614
615  // verify nmethod
616  debug_only(if (nm) nm->verify();) // might block
617
618  if (nm != NULL) {
619    nm->log_new_nmethod();
620  }
621
622  // done
623  return nm;
624}
625
626
627// For native wrappers
628nmethod::nmethod(
629  methodOop method,
630  int nmethod_size,
631  int compile_id,
632  CodeOffsets* offsets,
633  CodeBuffer* code_buffer,
634  int frame_size,
635  ByteSize basic_lock_owner_sp_offset,
636  ByteSize basic_lock_sp_offset,
637  OopMapSet* oop_maps )
638  : CodeBlob("native nmethod", code_buffer, sizeof(nmethod),
639             nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
640  _native_receiver_sp_offset(basic_lock_owner_sp_offset),
641  _native_basic_lock_sp_offset(basic_lock_sp_offset)
642{
643  {
644    debug_only(No_Safepoint_Verifier nsv;)
645    assert_locked_or_safepoint(CodeCache_lock);
646
647    init_defaults();
648    _method                  = method;
649    _entry_bci               = InvocationEntryBci;
650    // We have no exception handler or deopt handler make the
651    // values something that will never match a pc like the nmethod vtable entry
652    _exception_offset        = 0;
653    _deoptimize_offset       = 0;
654    _deoptimize_mh_offset    = 0;
655    _orig_pc_offset          = 0;
656
657    _consts_offset           = data_offset();
658    _stub_offset             = data_offset();
659    _oops_offset             = data_offset();
660    _scopes_data_offset      = _oops_offset          + round_to(code_buffer->total_oop_size(), oopSize);
661    _scopes_pcs_offset       = _scopes_data_offset;
662    _dependencies_offset     = _scopes_pcs_offset;
663    _handler_table_offset    = _dependencies_offset;
664    _nul_chk_table_offset    = _handler_table_offset;
665    _nmethod_end_offset      = _nul_chk_table_offset;
666    _compile_id              = compile_id;
667    _comp_level              = CompLevel_none;
668    _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
669    _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
670    _osr_entry_point         = NULL;
671    _exception_cache         = NULL;
672    _pc_desc_cache.reset_to(NULL);
673
674    code_buffer->copy_oops_to(this);
675    if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
676      CodeCache::add_scavenge_root_nmethod(this);
677    }
678    debug_only(verify_scavenge_root_oops());
679    CodeCache::commit(this);
680  }
681
682  if (PrintNativeNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
683    ttyLocker ttyl;  // keep the following output all in one block
684    // This output goes directly to the tty, not the compiler log.
685    // To enable tools to match it up with the compilation activity,
686    // be sure to tag this tty output with the compile ID.
687    if (xtty != NULL) {
688      xtty->begin_head("print_native_nmethod");
689      xtty->method(_method);
690      xtty->stamp();
691      xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
692    }
693    // print the header part first
694    print();
695    // then print the requested information
696    if (PrintNativeNMethods) {
697      print_code();
698      oop_maps->print();
699    }
700    if (PrintRelocations) {
701      print_relocations();
702    }
703    if (xtty != NULL) {
704      xtty->tail("print_native_nmethod");
705    }
706  }
707  Events::log("Create nmethod " INTPTR_FORMAT, this);
708}
709
710// For dtrace wrappers
711#ifdef HAVE_DTRACE_H
712nmethod::nmethod(
713  methodOop method,
714  int nmethod_size,
715  CodeOffsets* offsets,
716  CodeBuffer* code_buffer,
717  int frame_size)
718  : CodeBlob("dtrace nmethod", code_buffer, sizeof(nmethod),
719             nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, NULL),
720  _native_receiver_sp_offset(in_ByteSize(-1)),
721  _native_basic_lock_sp_offset(in_ByteSize(-1))
722{
723  {
724    debug_only(No_Safepoint_Verifier nsv;)
725    assert_locked_or_safepoint(CodeCache_lock);
726
727    init_defaults();
728    _method                  = method;
729    _entry_bci               = InvocationEntryBci;
730    // We have no exception handler or deopt handler make the
731    // values something that will never match a pc like the nmethod vtable entry
732    _exception_offset        = 0;
733    _deoptimize_offset       = 0;
734    _deoptimize_mh_offset    = 0;
735    _unwind_handler_offset   = -1;
736    _trap_offset             = offsets->value(CodeOffsets::Dtrace_trap);
737    _orig_pc_offset          = 0;
738    _consts_offset           = data_offset();
739    _stub_offset             = data_offset();
740    _oops_offset             = data_offset();
741    _scopes_data_offset      = _oops_offset          + round_to(code_buffer->total_oop_size(), oopSize);
742    _scopes_pcs_offset       = _scopes_data_offset;
743    _dependencies_offset     = _scopes_pcs_offset;
744    _handler_table_offset    = _dependencies_offset;
745    _nul_chk_table_offset    = _handler_table_offset;
746    _nmethod_end_offset      = _nul_chk_table_offset;
747    _compile_id              = 0;  // default
748    _comp_level              = CompLevel_none;
749    _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
750    _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
751    _osr_entry_point         = NULL;
752    _exception_cache         = NULL;
753    _pc_desc_cache.reset_to(NULL);
754
755    code_buffer->copy_oops_to(this);
756    debug_only(verify_scavenge_root_oops());
757    CodeCache::commit(this);
758  }
759
760  if (PrintNMethods || PrintDebugInfo || PrintRelocations || PrintDependencies) {
761    ttyLocker ttyl;  // keep the following output all in one block
762    // This output goes directly to the tty, not the compiler log.
763    // To enable tools to match it up with the compilation activity,
764    // be sure to tag this tty output with the compile ID.
765    if (xtty != NULL) {
766      xtty->begin_head("print_dtrace_nmethod");
767      xtty->method(_method);
768      xtty->stamp();
769      xtty->end_head(" address='" INTPTR_FORMAT "'", (intptr_t) this);
770    }
771    // print the header part first
772    print();
773    // then print the requested information
774    if (PrintNMethods) {
775      print_code();
776    }
777    if (PrintRelocations) {
778      print_relocations();
779    }
780    if (xtty != NULL) {
781      xtty->tail("print_dtrace_nmethod");
782    }
783  }
784  Events::log("Create nmethod " INTPTR_FORMAT, this);
785}
786#endif // def HAVE_DTRACE_H
787
788void* nmethod::operator new(size_t size, int nmethod_size) {
789  // Always leave some room in the CodeCache for I2C/C2I adapters
790  if (CodeCache::largest_free_block() < CodeCacheMinimumFreeSpace) return NULL;
791  return CodeCache::allocate(nmethod_size);
792}
793
794
795nmethod::nmethod(
796  methodOop method,
797  int nmethod_size,
798  int compile_id,
799  int entry_bci,
800  CodeOffsets* offsets,
801  int orig_pc_offset,
802  DebugInformationRecorder* debug_info,
803  Dependencies* dependencies,
804  CodeBuffer *code_buffer,
805  int frame_size,
806  OopMapSet* oop_maps,
807  ExceptionHandlerTable* handler_table,
808  ImplicitExceptionTable* nul_chk_table,
809  AbstractCompiler* compiler,
810  int comp_level
811  )
812  : CodeBlob("nmethod", code_buffer, sizeof(nmethod),
813             nmethod_size, offsets->value(CodeOffsets::Frame_Complete), frame_size, oop_maps),
814  _native_receiver_sp_offset(in_ByteSize(-1)),
815  _native_basic_lock_sp_offset(in_ByteSize(-1))
816{
817  assert(debug_info->oop_recorder() == code_buffer->oop_recorder(), "shared OR");
818  {
819    debug_only(No_Safepoint_Verifier nsv;)
820    assert_locked_or_safepoint(CodeCache_lock);
821
822    init_defaults();
823    _method                  = method;
824    _entry_bci               = entry_bci;
825    _compile_id              = compile_id;
826    _comp_level              = comp_level;
827    _compiler                = compiler;
828    _orig_pc_offset          = orig_pc_offset;
829
830    // Section offsets
831    _consts_offset           = content_offset()      + code_buffer->total_offset_of(code_buffer->consts());
832    _stub_offset             = content_offset()      + code_buffer->total_offset_of(code_buffer->stubs());
833
834    // Exception handler and deopt handler are in the stub section
835    assert(offsets->value(CodeOffsets::Exceptions) != -1, "must be set");
836    assert(offsets->value(CodeOffsets::Deopt     ) != -1, "must be set");
837    _exception_offset        = _stub_offset          + offsets->value(CodeOffsets::Exceptions);
838    _deoptimize_offset       = _stub_offset          + offsets->value(CodeOffsets::Deopt);
839    if (offsets->value(CodeOffsets::DeoptMH) != -1) {
840      _deoptimize_mh_offset  = _stub_offset          + offsets->value(CodeOffsets::DeoptMH);
841    } else {
842      _deoptimize_mh_offset  = -1;
843    }
844    if (offsets->value(CodeOffsets::UnwindHandler) != -1) {
845      _unwind_handler_offset = code_offset()         + offsets->value(CodeOffsets::UnwindHandler);
846    } else {
847      _unwind_handler_offset = -1;
848    }
849
850    _oops_offset             = data_offset();
851    _scopes_data_offset      = _oops_offset          + round_to(code_buffer->total_oop_size (), oopSize);
852    _scopes_pcs_offset       = _scopes_data_offset   + round_to(debug_info->data_size       (), oopSize);
853    _dependencies_offset     = _scopes_pcs_offset    + adjust_pcs_size(debug_info->pcs_size());
854    _handler_table_offset    = _dependencies_offset  + round_to(dependencies->size_in_bytes (), oopSize);
855    _nul_chk_table_offset    = _handler_table_offset + round_to(handler_table->size_in_bytes(), oopSize);
856    _nmethod_end_offset      = _nul_chk_table_offset + round_to(nul_chk_table->size_in_bytes(), oopSize);
857
858    _entry_point             = code_begin()          + offsets->value(CodeOffsets::Entry);
859    _verified_entry_point    = code_begin()          + offsets->value(CodeOffsets::Verified_Entry);
860    _osr_entry_point         = code_begin()          + offsets->value(CodeOffsets::OSR_Entry);
861    _exception_cache         = NULL;
862    _pc_desc_cache.reset_to(scopes_pcs_begin());
863
864    // Copy contents of ScopeDescRecorder to nmethod
865    code_buffer->copy_oops_to(this);
866    debug_info->copy_to(this);
867    dependencies->copy_to(this);
868    if (ScavengeRootsInCode && detect_scavenge_root_oops()) {
869      CodeCache::add_scavenge_root_nmethod(this);
870    }
871    debug_only(verify_scavenge_root_oops());
872
873    CodeCache::commit(this);
874
875    // Copy contents of ExceptionHandlerTable to nmethod
876    handler_table->copy_to(this);
877    nul_chk_table->copy_to(this);
878
879    // we use the information of entry points to find out if a method is
880    // static or non static
881    assert(compiler->is_c2() ||
882           _method->is_static() == (entry_point() == _verified_entry_point),
883           " entry points must be same for static methods and vice versa");
884  }
885
886  bool printnmethods = PrintNMethods
887    || CompilerOracle::should_print(_method)
888    || CompilerOracle::has_option_string(_method, "PrintNMethods");
889  if (printnmethods || PrintDebugInfo || PrintRelocations || PrintDependencies || PrintExceptionHandlers) {
890    print_nmethod(printnmethods);
891  }
892
893  // Note: Do not verify in here as the CodeCache_lock is
894  //       taken which would conflict with the CompiledIC_lock
895  //       which taken during the verification of call sites.
896  //       (was bug - gri 10/25/99)
897
898  Events::log("Create nmethod " INTPTR_FORMAT, this);
899}
900
901
902// Print a short set of xml attributes to identify this nmethod.  The
903// output should be embedded in some other element.
904void nmethod::log_identity(xmlStream* log) const {
905  log->print(" compile_id='%d'", compile_id());
906  const char* nm_kind = compile_kind();
907  if (nm_kind != NULL)  log->print(" compile_kind='%s'", nm_kind);
908  if (compiler() != NULL) {
909    log->print(" compiler='%s'", compiler()->name());
910  }
911  if (TieredCompilation) {
912    log->print(" level='%d'", comp_level());
913  }
914}
915
916
917#define LOG_OFFSET(log, name)                    \
918  if ((intptr_t)name##_end() - (intptr_t)name##_begin()) \
919    log->print(" " XSTR(name) "_offset='%d'"    , \
920               (intptr_t)name##_begin() - (intptr_t)this)
921
922
923void nmethod::log_new_nmethod() const {
924  if (LogCompilation && xtty != NULL) {
925    ttyLocker ttyl;
926    HandleMark hm;
927    xtty->begin_elem("nmethod");
928    log_identity(xtty);
929    xtty->print(" entry='" INTPTR_FORMAT "' size='%d'", code_begin(), size());
930    xtty->print(" address='" INTPTR_FORMAT "'", (intptr_t) this);
931
932    LOG_OFFSET(xtty, relocation);
933    LOG_OFFSET(xtty, consts);
934    LOG_OFFSET(xtty, insts);
935    LOG_OFFSET(xtty, stub);
936    LOG_OFFSET(xtty, scopes_data);
937    LOG_OFFSET(xtty, scopes_pcs);
938    LOG_OFFSET(xtty, dependencies);
939    LOG_OFFSET(xtty, handler_table);
940    LOG_OFFSET(xtty, nul_chk_table);
941    LOG_OFFSET(xtty, oops);
942
943    xtty->method(method());
944    xtty->stamp();
945    xtty->end_elem();
946  }
947}
948
949#undef LOG_OFFSET
950
951
952// Print out more verbose output usually for a newly created nmethod.
953void nmethod::print_on(outputStream* st, const char* msg) const {
954  if (st != NULL) {
955    ttyLocker ttyl;
956    CompileTask::print_compilation(st, this, msg);
957    if (WizardMode) st->print(" (" INTPTR_FORMAT ")", this);
958  }
959}
960
961
962void nmethod::print_nmethod(bool printmethod) {
963  ttyLocker ttyl;  // keep the following output all in one block
964  if (xtty != NULL) {
965    xtty->begin_head("print_nmethod");
966    xtty->stamp();
967    xtty->end_head();
968  }
969  // print the header part first
970  print();
971  // then print the requested information
972  if (printmethod) {
973    print_code();
974    print_pcs();
975    oop_maps()->print();
976  }
977  if (PrintDebugInfo) {
978    print_scopes();
979  }
980  if (PrintRelocations) {
981    print_relocations();
982  }
983  if (PrintDependencies) {
984    print_dependencies();
985  }
986  if (PrintExceptionHandlers) {
987    print_handler_table();
988    print_nul_chk_table();
989  }
990  if (xtty != NULL) {
991    xtty->tail("print_nmethod");
992  }
993}
994
995
996// Promote one word from an assembly-time handle to a live embedded oop.
997inline void nmethod::initialize_immediate_oop(oop* dest, jobject handle) {
998  if (handle == NULL ||
999      // As a special case, IC oops are initialized to 1 or -1.
1000      handle == (jobject) Universe::non_oop_word()) {
1001    (*dest) = (oop) handle;
1002  } else {
1003    (*dest) = JNIHandles::resolve_non_null(handle);
1004  }
1005}
1006
1007
1008void nmethod::copy_oops(GrowableArray<jobject>* array) {
1009  //assert(oops_size() == 0, "do this handshake just once, please");
1010  int length = array->length();
1011  assert((address)(oops_begin() + length) <= data_end(), "oops big enough");
1012  oop* dest = oops_begin();
1013  for (int index = 0 ; index < length; index++) {
1014    initialize_immediate_oop(&dest[index], array->at(index));
1015  }
1016
1017  // Now we can fix up all the oops in the code.  We need to do this
1018  // in the code because the assembler uses jobjects as placeholders.
1019  // The code and relocations have already been initialized by the
1020  // CodeBlob constructor, so it is valid even at this early point to
1021  // iterate over relocations and patch the code.
1022  fix_oop_relocations(NULL, NULL, /*initialize_immediates=*/ true);
1023}
1024
1025
1026bool nmethod::is_at_poll_return(address pc) {
1027  RelocIterator iter(this, pc, pc+1);
1028  while (iter.next()) {
1029    if (iter.type() == relocInfo::poll_return_type)
1030      return true;
1031  }
1032  return false;
1033}
1034
1035
1036bool nmethod::is_at_poll_or_poll_return(address pc) {
1037  RelocIterator iter(this, pc, pc+1);
1038  while (iter.next()) {
1039    relocInfo::relocType t = iter.type();
1040    if (t == relocInfo::poll_return_type || t == relocInfo::poll_type)
1041      return true;
1042  }
1043  return false;
1044}
1045
1046
1047void nmethod::fix_oop_relocations(address begin, address end, bool initialize_immediates) {
1048  // re-patch all oop-bearing instructions, just in case some oops moved
1049  RelocIterator iter(this, begin, end);
1050  while (iter.next()) {
1051    if (iter.type() == relocInfo::oop_type) {
1052      oop_Relocation* reloc = iter.oop_reloc();
1053      if (initialize_immediates && reloc->oop_is_immediate()) {
1054        oop* dest = reloc->oop_addr();
1055        initialize_immediate_oop(dest, (jobject) *dest);
1056      }
1057      // Refresh the oop-related bits of this instruction.
1058      reloc->fix_oop_relocation();
1059    }
1060
1061    // There must not be any interfering patches or breakpoints.
1062    assert(!(iter.type() == relocInfo::breakpoint_type
1063             && iter.breakpoint_reloc()->active()),
1064           "no active breakpoint");
1065  }
1066}
1067
1068
1069void nmethod::verify_oop_relocations() {
1070  // Ensure sure that the code matches the current oop values
1071  RelocIterator iter(this, NULL, NULL);
1072  while (iter.next()) {
1073    if (iter.type() == relocInfo::oop_type) {
1074      oop_Relocation* reloc = iter.oop_reloc();
1075      if (!reloc->oop_is_immediate()) {
1076        reloc->verify_oop_relocation();
1077      }
1078    }
1079  }
1080}
1081
1082
1083ScopeDesc* nmethod::scope_desc_at(address pc) {
1084  PcDesc* pd = pc_desc_at(pc);
1085  guarantee(pd != NULL, "scope must be present");
1086  return new ScopeDesc(this, pd->scope_decode_offset(),
1087                       pd->obj_decode_offset(), pd->should_reexecute(),
1088                       pd->return_oop());
1089}
1090
1091
1092void nmethod::clear_inline_caches() {
1093  assert(SafepointSynchronize::is_at_safepoint(), "cleaning of IC's only allowed at safepoint");
1094  if (is_zombie()) {
1095    return;
1096  }
1097
1098  RelocIterator iter(this);
1099  while (iter.next()) {
1100    iter.reloc()->clear_inline_cache();
1101  }
1102}
1103
1104
1105void nmethod::cleanup_inline_caches() {
1106
1107  assert_locked_or_safepoint(CompiledIC_lock);
1108
1109  // If the method is not entrant or zombie then a JMP is plastered over the
1110  // first few bytes.  If an oop in the old code was there, that oop
1111  // should not get GC'd.  Skip the first few bytes of oops on
1112  // not-entrant methods.
1113  address low_boundary = verified_entry_point();
1114  if (!is_in_use()) {
1115    low_boundary += NativeJump::instruction_size;
1116    // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
1117    // This means that the low_boundary is going to be a little too high.
1118    // This shouldn't matter, since oops of non-entrant methods are never used.
1119    // In fact, why are we bothering to look at oops in a non-entrant method??
1120  }
1121
1122  // Find all calls in an nmethod, and clear the ones that points to zombie methods
1123  ResourceMark rm;
1124  RelocIterator iter(this, low_boundary);
1125  while(iter.next()) {
1126    switch(iter.type()) {
1127      case relocInfo::virtual_call_type:
1128      case relocInfo::opt_virtual_call_type: {
1129        CompiledIC *ic = CompiledIC_at(iter.reloc());
1130        // Ok, to lookup references to zombies here
1131        CodeBlob *cb = CodeCache::find_blob_unsafe(ic->ic_destination());
1132        if( cb != NULL && cb->is_nmethod() ) {
1133          nmethod* nm = (nmethod*)cb;
1134          // Clean inline caches pointing to both zombie and not_entrant methods
1135          if (!nm->is_in_use() || (nm->method()->code() != nm)) ic->set_to_clean();
1136        }
1137        break;
1138      }
1139      case relocInfo::static_call_type: {
1140        CompiledStaticCall *csc = compiledStaticCall_at(iter.reloc());
1141        CodeBlob *cb = CodeCache::find_blob_unsafe(csc->destination());
1142        if( cb != NULL && cb->is_nmethod() ) {
1143          nmethod* nm = (nmethod*)cb;
1144          // Clean inline caches pointing to both zombie and not_entrant methods
1145          if (!nm->is_in_use() || (nm->method()->code() != nm)) csc->set_to_clean();
1146        }
1147        break;
1148      }
1149    }
1150  }
1151}
1152
1153// This is a private interface with the sweeper.
1154void nmethod::mark_as_seen_on_stack() {
1155  assert(is_not_entrant(), "must be a non-entrant method");
1156  // Set the traversal mark to ensure that the sweeper does 2
1157  // cleaning passes before moving to zombie.
1158  set_stack_traversal_mark(NMethodSweeper::traversal_count());
1159}
1160
1161// Tell if a non-entrant method can be converted to a zombie (i.e.,
1162// there are no activations on the stack, not in use by the VM,
1163// and not in use by the ServiceThread)
1164bool nmethod::can_not_entrant_be_converted() {
1165  assert(is_not_entrant(), "must be a non-entrant method");
1166
1167  // Since the nmethod sweeper only does partial sweep the sweeper's traversal
1168  // count can be greater than the stack traversal count before it hits the
1169  // nmethod for the second time.
1170  return stack_traversal_mark()+1 < NMethodSweeper::traversal_count() &&
1171         !is_locked_by_vm();
1172}
1173
1174void nmethod::inc_decompile_count() {
1175  if (!is_compiled_by_c2()) return;
1176  // Could be gated by ProfileTraps, but do not bother...
1177  methodOop m = method();
1178  if (m == NULL)  return;
1179  methodDataOop mdo = m->method_data();
1180  if (mdo == NULL)  return;
1181  // There is a benign race here.  See comments in methodDataOop.hpp.
1182  mdo->inc_decompile_count();
1183}
1184
1185void nmethod::make_unloaded(BoolObjectClosure* is_alive, oop cause) {
1186
1187  post_compiled_method_unload();
1188
1189  // Since this nmethod is being unloaded, make sure that dependencies
1190  // recorded in instanceKlasses get flushed and pass non-NULL closure to
1191  // indicate that this work is being done during a GC.
1192  assert(Universe::heap()->is_gc_active(), "should only be called during gc");
1193  assert(is_alive != NULL, "Should be non-NULL");
1194  // A non-NULL is_alive closure indicates that this is being called during GC.
1195  flush_dependencies(is_alive);
1196
1197  // Break cycle between nmethod & method
1198  if (TraceClassUnloading && WizardMode) {
1199    tty->print_cr("[Class unloading: Making nmethod " INTPTR_FORMAT
1200                  " unloadable], methodOop(" INTPTR_FORMAT
1201                  "), cause(" INTPTR_FORMAT ")",
1202                  this, (address)_method, (address)cause);
1203    if (!Universe::heap()->is_gc_active())
1204      cause->klass()->print();
1205  }
1206  // Unlink the osr method, so we do not look this up again
1207  if (is_osr_method()) {
1208    invalidate_osr_method();
1209  }
1210  // If _method is already NULL the methodOop is about to be unloaded,
1211  // so we don't have to break the cycle. Note that it is possible to
1212  // have the methodOop live here, in case we unload the nmethod because
1213  // it is pointing to some oop (other than the methodOop) being unloaded.
1214  if (_method != NULL) {
1215    // OSR methods point to the methodOop, but the methodOop does not
1216    // point back!
1217    if (_method->code() == this) {
1218      _method->clear_code(); // Break a cycle
1219    }
1220    _method = NULL;            // Clear the method of this dead nmethod
1221  }
1222  // Make the class unloaded - i.e., change state and notify sweeper
1223  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1224  if (is_in_use()) {
1225    // Transitioning directly from live to unloaded -- so
1226    // we need to force a cache clean-up; remember this
1227    // for later on.
1228    CodeCache::set_needs_cache_clean(true);
1229  }
1230  _state = unloaded;
1231
1232  // Log the unloading.
1233  log_state_change();
1234
1235  // The methodOop is gone at this point
1236  assert(_method == NULL, "Tautology");
1237
1238  set_osr_link(NULL);
1239  //set_scavenge_root_link(NULL); // done by prune_scavenge_root_nmethods
1240  NMethodSweeper::notify(this);
1241}
1242
1243void nmethod::invalidate_osr_method() {
1244  assert(_entry_bci != InvocationEntryBci, "wrong kind of nmethod");
1245  // Remove from list of active nmethods
1246  if (method() != NULL)
1247    instanceKlass::cast(method()->method_holder())->remove_osr_nmethod(this);
1248  // Set entry as invalid
1249  _entry_bci = InvalidOSREntryBci;
1250}
1251
1252void nmethod::log_state_change() const {
1253  if (LogCompilation) {
1254    if (xtty != NULL) {
1255      ttyLocker ttyl;  // keep the following output all in one block
1256      if (_state == unloaded) {
1257        xtty->begin_elem("make_unloaded thread='" UINTX_FORMAT "'",
1258                         os::current_thread_id());
1259      } else {
1260        xtty->begin_elem("make_not_entrant thread='" UINTX_FORMAT "'%s",
1261                         os::current_thread_id(),
1262                         (_state == zombie ? " zombie='1'" : ""));
1263      }
1264      log_identity(xtty);
1265      xtty->stamp();
1266      xtty->end_elem();
1267    }
1268  }
1269  if (PrintCompilation && _state != unloaded) {
1270    print_on(tty, _state == zombie ? "made zombie" : "made not entrant");
1271  }
1272}
1273
1274// Common functionality for both make_not_entrant and make_zombie
1275bool nmethod::make_not_entrant_or_zombie(unsigned int state) {
1276  assert(state == zombie || state == not_entrant, "must be zombie or not_entrant");
1277  assert(!is_zombie(), "should not already be a zombie");
1278
1279  // Make sure neither the nmethod nor the method is flushed in case of a safepoint in code below.
1280  nmethodLocker nml(this);
1281  methodHandle the_method(method());
1282  No_Safepoint_Verifier nsv;
1283
1284  {
1285    // invalidate osr nmethod before acquiring the patching lock since
1286    // they both acquire leaf locks and we don't want a deadlock.
1287    // This logic is equivalent to the logic below for patching the
1288    // verified entry point of regular methods.
1289    if (is_osr_method()) {
1290      // this effectively makes the osr nmethod not entrant
1291      invalidate_osr_method();
1292    }
1293
1294    // Enter critical section.  Does not block for safepoint.
1295    MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
1296
1297    if (_state == state) {
1298      // another thread already performed this transition so nothing
1299      // to do, but return false to indicate this.
1300      return false;
1301    }
1302
1303    // The caller can be calling the method statically or through an inline
1304    // cache call.
1305    if (!is_osr_method() && !is_not_entrant()) {
1306      NativeJump::patch_verified_entry(entry_point(), verified_entry_point(),
1307                  SharedRuntime::get_handle_wrong_method_stub());
1308    }
1309
1310    if (is_in_use()) {
1311      // It's a true state change, so mark the method as decompiled.
1312      // Do it only for transition from alive.
1313      inc_decompile_count();
1314    }
1315
1316    // Change state
1317    _state = state;
1318
1319    // Log the transition once
1320    log_state_change();
1321
1322    // Remove nmethod from method.
1323    // We need to check if both the _code and _from_compiled_code_entry_point
1324    // refer to this nmethod because there is a race in setting these two fields
1325    // in methodOop as seen in bugid 4947125.
1326    // If the vep() points to the zombie nmethod, the memory for the nmethod
1327    // could be flushed and the compiler and vtable stubs could still call
1328    // through it.
1329    if (method() != NULL && (method()->code() == this ||
1330                             method()->from_compiled_entry() == verified_entry_point())) {
1331      HandleMark hm;
1332      method()->clear_code();
1333    }
1334
1335    if (state == not_entrant) {
1336      mark_as_seen_on_stack();
1337    }
1338
1339  } // leave critical region under Patching_lock
1340
1341  // When the nmethod becomes zombie it is no longer alive so the
1342  // dependencies must be flushed.  nmethods in the not_entrant
1343  // state will be flushed later when the transition to zombie
1344  // happens or they get unloaded.
1345  if (state == zombie) {
1346    {
1347      // Flushing dependecies must be done before any possible
1348      // safepoint can sneak in, otherwise the oops used by the
1349      // dependency logic could have become stale.
1350      MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
1351      flush_dependencies(NULL);
1352    }
1353
1354    // zombie only - if a JVMTI agent has enabled the CompiledMethodUnload
1355    // event and it hasn't already been reported for this nmethod then
1356    // report it now. The event may have been reported earilier if the GC
1357    // marked it for unloading). JvmtiDeferredEventQueue support means
1358    // we no longer go to a safepoint here.
1359    post_compiled_method_unload();
1360
1361#ifdef ASSERT
1362    // It's no longer safe to access the oops section since zombie
1363    // nmethods aren't scanned for GC.
1364    _oops_are_stale = true;
1365#endif
1366  } else {
1367    assert(state == not_entrant, "other cases may need to be handled differently");
1368  }
1369
1370  if (TraceCreateZombies) {
1371    tty->print_cr("nmethod <" INTPTR_FORMAT "> code made %s", this, (state == not_entrant) ? "not entrant" : "zombie");
1372  }
1373
1374  // Make sweeper aware that there is a zombie method that needs to be removed
1375  NMethodSweeper::notify(this);
1376
1377  return true;
1378}
1379
1380void nmethod::flush() {
1381  // Note that there are no valid oops in the nmethod anymore.
1382  assert(is_zombie() || (is_osr_method() && is_unloaded()), "must be a zombie method");
1383  assert(is_marked_for_reclamation() || (is_osr_method() && is_unloaded()), "must be marked for reclamation");
1384
1385  assert (!is_locked_by_vm(), "locked methods shouldn't be flushed");
1386  assert_locked_or_safepoint(CodeCache_lock);
1387
1388  // completely deallocate this method
1389  EventMark m("flushing nmethod " INTPTR_FORMAT " %s", this, "");
1390  if (PrintMethodFlushing) {
1391    tty->print_cr("*flushing nmethod %3d/" INTPTR_FORMAT ". Live blobs:" UINT32_FORMAT "/Free CodeCache:" SIZE_FORMAT "Kb",
1392        _compile_id, this, CodeCache::nof_blobs(), CodeCache::unallocated_capacity()/1024);
1393  }
1394
1395  // We need to deallocate any ExceptionCache data.
1396  // Note that we do not need to grab the nmethod lock for this, it
1397  // better be thread safe if we're disposing of it!
1398  ExceptionCache* ec = exception_cache();
1399  set_exception_cache(NULL);
1400  while(ec != NULL) {
1401    ExceptionCache* next = ec->next();
1402    delete ec;
1403    ec = next;
1404  }
1405
1406  if (on_scavenge_root_list()) {
1407    CodeCache::drop_scavenge_root_nmethod(this);
1408  }
1409
1410  if (is_speculatively_disconnected()) {
1411    CodeCache::remove_saved_code(this);
1412  }
1413
1414#ifdef SHARK
1415  ((SharkCompiler *) compiler())->free_compiled_method(insts_begin());
1416#endif // SHARK
1417
1418  ((CodeBlob*)(this))->flush();
1419
1420  CodeCache::free(this);
1421}
1422
1423
1424//
1425// Notify all classes this nmethod is dependent on that it is no
1426// longer dependent. This should only be called in two situations.
1427// First, when a nmethod transitions to a zombie all dependents need
1428// to be clear.  Since zombification happens at a safepoint there's no
1429// synchronization issues.  The second place is a little more tricky.
1430// During phase 1 of mark sweep class unloading may happen and as a
1431// result some nmethods may get unloaded.  In this case the flushing
1432// of dependencies must happen during phase 1 since after GC any
1433// dependencies in the unloaded nmethod won't be updated, so
1434// traversing the dependency information in unsafe.  In that case this
1435// function is called with a non-NULL argument and this function only
1436// notifies instanceKlasses that are reachable
1437
1438void nmethod::flush_dependencies(BoolObjectClosure* is_alive) {
1439  assert_locked_or_safepoint(CodeCache_lock);
1440  assert(Universe::heap()->is_gc_active() == (is_alive != NULL),
1441  "is_alive is non-NULL if and only if we are called during GC");
1442  if (!has_flushed_dependencies()) {
1443    set_has_flushed_dependencies();
1444    for (Dependencies::DepStream deps(this); deps.next(); ) {
1445      klassOop klass = deps.context_type();
1446      if (klass == NULL)  continue;  // ignore things like evol_method
1447
1448      // During GC the is_alive closure is non-NULL, and is used to
1449      // determine liveness of dependees that need to be updated.
1450      if (is_alive == NULL || is_alive->do_object_b(klass)) {
1451        instanceKlass::cast(klass)->remove_dependent_nmethod(this);
1452      }
1453    }
1454  }
1455}
1456
1457
1458// If this oop is not live, the nmethod can be unloaded.
1459bool nmethod::can_unload(BoolObjectClosure* is_alive,
1460                         OopClosure* keep_alive,
1461                         oop* root, bool unloading_occurred) {
1462  assert(root != NULL, "just checking");
1463  oop obj = *root;
1464  if (obj == NULL || is_alive->do_object_b(obj)) {
1465      return false;
1466  }
1467  if (obj->is_compiledICHolder()) {
1468    compiledICHolderOop cichk_oop = compiledICHolderOop(obj);
1469    if (is_alive->do_object_b(
1470          cichk_oop->holder_method()->method_holder()) &&
1471        is_alive->do_object_b(cichk_oop->holder_klass())) {
1472      // The oop should be kept alive
1473      keep_alive->do_oop(root);
1474      return false;
1475    }
1476  }
1477  // If ScavengeRootsInCode is true, an nmethod might be unloaded
1478  // simply because one of its constant oops has gone dead.
1479  // No actual classes need to be unloaded in order for this to occur.
1480  assert(unloading_occurred || ScavengeRootsInCode, "Inconsistency in unloading");
1481  make_unloaded(is_alive, obj);
1482  return true;
1483}
1484
1485// ------------------------------------------------------------------
1486// post_compiled_method_load_event
1487// new method for install_code() path
1488// Transfer information from compilation to jvmti
1489void nmethod::post_compiled_method_load_event() {
1490
1491  methodOop moop = method();
1492#ifndef USDT2
1493  HS_DTRACE_PROBE8(hotspot, compiled__method__load,
1494      moop->klass_name()->bytes(),
1495      moop->klass_name()->utf8_length(),
1496      moop->name()->bytes(),
1497      moop->name()->utf8_length(),
1498      moop->signature()->bytes(),
1499      moop->signature()->utf8_length(),
1500      insts_begin(), insts_size());
1501#else /* USDT2 */
1502  HOTSPOT_COMPILED_METHOD_LOAD(
1503      (char *) moop->klass_name()->bytes(),
1504      moop->klass_name()->utf8_length(),
1505      (char *) moop->name()->bytes(),
1506      moop->name()->utf8_length(),
1507      (char *) moop->signature()->bytes(),
1508      moop->signature()->utf8_length(),
1509      insts_begin(), insts_size());
1510#endif /* USDT2 */
1511
1512  if (JvmtiExport::should_post_compiled_method_load() ||
1513      JvmtiExport::should_post_compiled_method_unload()) {
1514    get_and_cache_jmethod_id();
1515  }
1516
1517  if (JvmtiExport::should_post_compiled_method_load()) {
1518    // Let the Service thread (which is a real Java thread) post the event
1519    MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1520    JvmtiDeferredEventQueue::enqueue(
1521      JvmtiDeferredEvent::compiled_method_load_event(this));
1522  }
1523}
1524
1525jmethodID nmethod::get_and_cache_jmethod_id() {
1526  if (_jmethod_id == NULL) {
1527    // Cache the jmethod_id since it can no longer be looked up once the
1528    // method itself has been marked for unloading.
1529    _jmethod_id = method()->jmethod_id();
1530  }
1531  return _jmethod_id;
1532}
1533
1534void nmethod::post_compiled_method_unload() {
1535  if (unload_reported()) {
1536    // During unloading we transition to unloaded and then to zombie
1537    // and the unloading is reported during the first transition.
1538    return;
1539  }
1540
1541  assert(_method != NULL && !is_unloaded(), "just checking");
1542  DTRACE_METHOD_UNLOAD_PROBE(method());
1543
1544  // If a JVMTI agent has enabled the CompiledMethodUnload event then
1545  // post the event. Sometime later this nmethod will be made a zombie
1546  // by the sweeper but the methodOop will not be valid at that point.
1547  // If the _jmethod_id is null then no load event was ever requested
1548  // so don't bother posting the unload.  The main reason for this is
1549  // that the jmethodID is a weak reference to the methodOop so if
1550  // it's being unloaded there's no way to look it up since the weak
1551  // ref will have been cleared.
1552  if (_jmethod_id != NULL && JvmtiExport::should_post_compiled_method_unload()) {
1553    assert(!unload_reported(), "already unloaded");
1554    JvmtiDeferredEvent event =
1555      JvmtiDeferredEvent::compiled_method_unload_event(this,
1556          _jmethod_id, insts_begin());
1557    if (SafepointSynchronize::is_at_safepoint()) {
1558      // Don't want to take the queueing lock. Add it as pending and
1559      // it will get enqueued later.
1560      JvmtiDeferredEventQueue::add_pending_event(event);
1561    } else {
1562      MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag);
1563      JvmtiDeferredEventQueue::enqueue(event);
1564    }
1565  }
1566
1567  // The JVMTI CompiledMethodUnload event can be enabled or disabled at
1568  // any time. As the nmethod is being unloaded now we mark it has
1569  // having the unload event reported - this will ensure that we don't
1570  // attempt to report the event in the unlikely scenario where the
1571  // event is enabled at the time the nmethod is made a zombie.
1572  set_unload_reported();
1573}
1574
1575// This is called at the end of the strong tracing/marking phase of a
1576// GC to unload an nmethod if it contains otherwise unreachable
1577// oops.
1578
1579void nmethod::do_unloading(BoolObjectClosure* is_alive,
1580                           OopClosure* keep_alive, bool unloading_occurred) {
1581  // Make sure the oop's ready to receive visitors
1582  assert(!is_zombie() && !is_unloaded(),
1583         "should not call follow on zombie or unloaded nmethod");
1584
1585  // If the method is not entrant then a JMP is plastered over the
1586  // first few bytes.  If an oop in the old code was there, that oop
1587  // should not get GC'd.  Skip the first few bytes of oops on
1588  // not-entrant methods.
1589  address low_boundary = verified_entry_point();
1590  if (is_not_entrant()) {
1591    low_boundary += NativeJump::instruction_size;
1592    // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
1593    // (See comment above.)
1594  }
1595
1596  // The RedefineClasses() API can cause the class unloading invariant
1597  // to no longer be true. See jvmtiExport.hpp for details.
1598  // Also, leave a debugging breadcrumb in local flag.
1599  bool a_class_was_redefined = JvmtiExport::has_redefined_a_class();
1600  if (a_class_was_redefined) {
1601    // This set of the unloading_occurred flag is done before the
1602    // call to post_compiled_method_unload() so that the unloading
1603    // of this nmethod is reported.
1604    unloading_occurred = true;
1605  }
1606
1607  // Follow methodOop
1608  if (can_unload(is_alive, keep_alive, (oop*)&_method, unloading_occurred)) {
1609    return;
1610  }
1611
1612  // Exception cache
1613  ExceptionCache* ec = exception_cache();
1614  while (ec != NULL) {
1615    oop* ex_addr = (oop*)ec->exception_type_addr();
1616    oop ex = *ex_addr;
1617    ExceptionCache* next_ec = ec->next();
1618    if (ex != NULL && !is_alive->do_object_b(ex)) {
1619      assert(!ex->is_compiledICHolder(), "Possible error here");
1620      remove_from_exception_cache(ec);
1621    }
1622    ec = next_ec;
1623  }
1624
1625  // If class unloading occurred we first iterate over all inline caches and
1626  // clear ICs where the cached oop is referring to an unloaded klass or method.
1627  // The remaining live cached oops will be traversed in the relocInfo::oop_type
1628  // iteration below.
1629  if (unloading_occurred) {
1630    RelocIterator iter(this, low_boundary);
1631    while(iter.next()) {
1632      if (iter.type() == relocInfo::virtual_call_type) {
1633        CompiledIC *ic = CompiledIC_at(iter.reloc());
1634        oop ic_oop = ic->cached_oop();
1635        if (ic_oop != NULL && !is_alive->do_object_b(ic_oop)) {
1636          // The only exception is compiledICHolder oops which may
1637          // yet be marked below. (We check this further below).
1638          if (ic_oop->is_compiledICHolder()) {
1639            compiledICHolderOop cichk_oop = compiledICHolderOop(ic_oop);
1640            if (is_alive->do_object_b(
1641                  cichk_oop->holder_method()->method_holder()) &&
1642                is_alive->do_object_b(cichk_oop->holder_klass())) {
1643              continue;
1644            }
1645          }
1646          ic->set_to_clean();
1647          assert(ic->cached_oop() == NULL,
1648                 "cached oop in IC should be cleared");
1649        }
1650      }
1651    }
1652  }
1653
1654  // Compiled code
1655  RelocIterator iter(this, low_boundary);
1656  while (iter.next()) {
1657    if (iter.type() == relocInfo::oop_type) {
1658      oop_Relocation* r = iter.oop_reloc();
1659      // In this loop, we must only traverse those oops directly embedded in
1660      // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
1661      assert(1 == (r->oop_is_immediate()) +
1662                  (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1663             "oop must be found in exactly one place");
1664      if (r->oop_is_immediate() && r->oop_value() != NULL) {
1665        if (can_unload(is_alive, keep_alive, r->oop_addr(), unloading_occurred)) {
1666          return;
1667        }
1668      }
1669    }
1670  }
1671
1672
1673  // Scopes
1674  for (oop* p = oops_begin(); p < oops_end(); p++) {
1675    if (*p == Universe::non_oop_word())  continue;  // skip non-oops
1676    if (can_unload(is_alive, keep_alive, p, unloading_occurred)) {
1677      return;
1678    }
1679  }
1680
1681#ifndef PRODUCT
1682  // This nmethod was not unloaded; check below that all CompiledICs
1683  // refer to marked oops.
1684  {
1685    RelocIterator iter(this, low_boundary);
1686    while (iter.next()) {
1687      if (iter.type() == relocInfo::virtual_call_type) {
1688         CompiledIC *ic = CompiledIC_at(iter.reloc());
1689         oop ic_oop = ic->cached_oop();
1690         assert(ic_oop == NULL || is_alive->do_object_b(ic_oop),
1691                "Found unmarked ic_oop in reachable nmethod");
1692       }
1693    }
1694  }
1695#endif // !PRODUCT
1696}
1697
1698// This method is called twice during GC -- once while
1699// tracing the "active" nmethods on thread stacks during
1700// the (strong) marking phase, and then again when walking
1701// the code cache contents during the weak roots processing
1702// phase. The two uses are distinguished by means of the
1703// 'do_strong_roots_only' flag, which is true in the first
1704// case. We want to walk the weak roots in the nmethod
1705// only in the second case. The weak roots in the nmethod
1706// are the oops in the ExceptionCache and the InlineCache
1707// oops.
1708void nmethod::oops_do(OopClosure* f, bool do_strong_roots_only) {
1709  // make sure the oops ready to receive visitors
1710  assert(!is_zombie() && !is_unloaded(),
1711         "should not call follow on zombie or unloaded nmethod");
1712
1713  // If the method is not entrant or zombie then a JMP is plastered over the
1714  // first few bytes.  If an oop in the old code was there, that oop
1715  // should not get GC'd.  Skip the first few bytes of oops on
1716  // not-entrant methods.
1717  address low_boundary = verified_entry_point();
1718  if (is_not_entrant()) {
1719    low_boundary += NativeJump::instruction_size;
1720    // %%% Note:  On SPARC we patch only a 4-byte trap, not a full NativeJump.
1721    // (See comment above.)
1722  }
1723
1724  // Compiled code
1725  f->do_oop((oop*) &_method);
1726  if (!do_strong_roots_only) {
1727    // weak roots processing phase -- update ExceptionCache oops
1728    ExceptionCache* ec = exception_cache();
1729    while(ec != NULL) {
1730      f->do_oop((oop*)ec->exception_type_addr());
1731      ec = ec->next();
1732    }
1733  } // Else strong roots phase -- skip oops in ExceptionCache
1734
1735  RelocIterator iter(this, low_boundary);
1736
1737  while (iter.next()) {
1738    if (iter.type() == relocInfo::oop_type ) {
1739      oop_Relocation* r = iter.oop_reloc();
1740      // In this loop, we must only follow those oops directly embedded in
1741      // the code.  Other oops (oop_index>0) are seen as part of scopes_oops.
1742      assert(1 == (r->oop_is_immediate()) +
1743                   (r->oop_addr() >= oops_begin() && r->oop_addr() < oops_end()),
1744             "oop must be found in exactly one place");
1745      if (r->oop_is_immediate() && r->oop_value() != NULL) {
1746        f->do_oop(r->oop_addr());
1747      }
1748    }
1749  }
1750
1751  // Scopes
1752  // This includes oop constants not inlined in the code stream.
1753  for (oop* p = oops_begin(); p < oops_end(); p++) {
1754    if (*p == Universe::non_oop_word())  continue;  // skip non-oops
1755    f->do_oop(p);
1756  }
1757}
1758
1759#define NMETHOD_SENTINEL ((nmethod*)badAddress)
1760
1761nmethod* volatile nmethod::_oops_do_mark_nmethods;
1762
1763// An nmethod is "marked" if its _mark_link is set non-null.
1764// Even if it is the end of the linked list, it will have a non-null link value,
1765// as long as it is on the list.
1766// This code must be MP safe, because it is used from parallel GC passes.
1767bool nmethod::test_set_oops_do_mark() {
1768  assert(nmethod::oops_do_marking_is_active(), "oops_do_marking_prologue must be called");
1769  nmethod* observed_mark_link = _oops_do_mark_link;
1770  if (observed_mark_link == NULL) {
1771    // Claim this nmethod for this thread to mark.
1772    observed_mark_link = (nmethod*)
1773      Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_link, NULL);
1774    if (observed_mark_link == NULL) {
1775
1776      // Atomically append this nmethod (now claimed) to the head of the list:
1777      nmethod* observed_mark_nmethods = _oops_do_mark_nmethods;
1778      for (;;) {
1779        nmethod* required_mark_nmethods = observed_mark_nmethods;
1780        _oops_do_mark_link = required_mark_nmethods;
1781        observed_mark_nmethods = (nmethod*)
1782          Atomic::cmpxchg_ptr(this, &_oops_do_mark_nmethods, required_mark_nmethods);
1783        if (observed_mark_nmethods == required_mark_nmethods)
1784          break;
1785      }
1786      // Mark was clear when we first saw this guy.
1787      NOT_PRODUCT(if (TraceScavenge)  print_on(tty, "oops_do, mark"));
1788      return false;
1789    }
1790  }
1791  // On fall through, another racing thread marked this nmethod before we did.
1792  return true;
1793}
1794
1795void nmethod::oops_do_marking_prologue() {
1796  NOT_PRODUCT(if (TraceScavenge)  tty->print_cr("[oops_do_marking_prologue"));
1797  assert(_oops_do_mark_nmethods == NULL, "must not call oops_do_marking_prologue twice in a row");
1798  // We use cmpxchg_ptr instead of regular assignment here because the user
1799  // may fork a bunch of threads, and we need them all to see the same state.
1800  void* observed = Atomic::cmpxchg_ptr(NMETHOD_SENTINEL, &_oops_do_mark_nmethods, NULL);
1801  guarantee(observed == NULL, "no races in this sequential code");
1802}
1803
1804void nmethod::oops_do_marking_epilogue() {
1805  assert(_oops_do_mark_nmethods != NULL, "must not call oops_do_marking_epilogue twice in a row");
1806  nmethod* cur = _oops_do_mark_nmethods;
1807  while (cur != NMETHOD_SENTINEL) {
1808    assert(cur != NULL, "not NULL-terminated");
1809    nmethod* next = cur->_oops_do_mark_link;
1810    cur->_oops_do_mark_link = NULL;
1811    cur->fix_oop_relocations();
1812    NOT_PRODUCT(if (TraceScavenge)  cur->print_on(tty, "oops_do, unmark"));
1813    cur = next;
1814  }
1815  void* required = _oops_do_mark_nmethods;
1816  void* observed = Atomic::cmpxchg_ptr(NULL, &_oops_do_mark_nmethods, required);
1817  guarantee(observed == required, "no races in this sequential code");
1818  NOT_PRODUCT(if (TraceScavenge)  tty->print_cr("oops_do_marking_epilogue]"));
1819}
1820
1821class DetectScavengeRoot: public OopClosure {
1822  bool     _detected_scavenge_root;
1823public:
1824  DetectScavengeRoot() : _detected_scavenge_root(false)
1825  { NOT_PRODUCT(_print_nm = NULL); }
1826  bool detected_scavenge_root() { return _detected_scavenge_root; }
1827  virtual void do_oop(oop* p) {
1828    if ((*p) != NULL && (*p)->is_scavengable()) {
1829      NOT_PRODUCT(maybe_print(p));
1830      _detected_scavenge_root = true;
1831    }
1832  }
1833  virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
1834
1835#ifndef PRODUCT
1836  nmethod* _print_nm;
1837  void maybe_print(oop* p) {
1838    if (_print_nm == NULL)  return;
1839    if (!_detected_scavenge_root)  _print_nm->print_on(tty, "new scavenge root");
1840    tty->print_cr(""PTR_FORMAT"[offset=%d] detected scavengable oop "PTR_FORMAT" (found at "PTR_FORMAT")",
1841                  _print_nm, (int)((intptr_t)p - (intptr_t)_print_nm),
1842                  (intptr_t)(*p), (intptr_t)p);
1843    (*p)->print();
1844  }
1845#endif //PRODUCT
1846};
1847
1848bool nmethod::detect_scavenge_root_oops() {
1849  DetectScavengeRoot detect_scavenge_root;
1850  NOT_PRODUCT(if (TraceScavenge)  detect_scavenge_root._print_nm = this);
1851  oops_do(&detect_scavenge_root);
1852  return detect_scavenge_root.detected_scavenge_root();
1853}
1854
1855// Method that knows how to preserve outgoing arguments at call. This method must be
1856// called with a frame corresponding to a Java invoke
1857void nmethod::preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) {
1858#ifndef SHARK
1859  if (!method()->is_native()) {
1860    SimpleScopeDesc ssd(this, fr.pc());
1861    Bytecode_invoke call(ssd.method(), ssd.bci());
1862    // compiled invokedynamic call sites have an implicit receiver at
1863    // resolution time, so make sure it gets GC'ed.
1864    bool has_receiver = !call.is_invokestatic();
1865    Symbol* signature = call.signature();
1866    fr.oops_compiled_arguments_do(signature, has_receiver, reg_map, f);
1867  }
1868#endif // !SHARK
1869}
1870
1871
1872oop nmethod::embeddedOop_at(u_char* p) {
1873  RelocIterator iter(this, p, p + 1);
1874  while (iter.next())
1875    if (iter.type() == relocInfo::oop_type) {
1876      return iter.oop_reloc()->oop_value();
1877    }
1878  return NULL;
1879}
1880
1881
1882inline bool includes(void* p, void* from, void* to) {
1883  return from <= p && p < to;
1884}
1885
1886
1887void nmethod::copy_scopes_pcs(PcDesc* pcs, int count) {
1888  assert(count >= 2, "must be sentinel values, at least");
1889
1890#ifdef ASSERT
1891  // must be sorted and unique; we do a binary search in find_pc_desc()
1892  int prev_offset = pcs[0].pc_offset();
1893  assert(prev_offset == PcDesc::lower_offset_limit,
1894         "must start with a sentinel");
1895  for (int i = 1; i < count; i++) {
1896    int this_offset = pcs[i].pc_offset();
1897    assert(this_offset > prev_offset, "offsets must be sorted");
1898    prev_offset = this_offset;
1899  }
1900  assert(prev_offset == PcDesc::upper_offset_limit,
1901         "must end with a sentinel");
1902#endif //ASSERT
1903
1904  // Search for MethodHandle invokes and tag the nmethod.
1905  for (int i = 0; i < count; i++) {
1906    if (pcs[i].is_method_handle_invoke()) {
1907      set_has_method_handle_invokes(true);
1908      break;
1909    }
1910  }
1911  assert(has_method_handle_invokes() == (_deoptimize_mh_offset != -1), "must have deopt mh handler");
1912
1913  int size = count * sizeof(PcDesc);
1914  assert(scopes_pcs_size() >= size, "oob");
1915  memcpy(scopes_pcs_begin(), pcs, size);
1916
1917  // Adjust the final sentinel downward.
1918  PcDesc* last_pc = &scopes_pcs_begin()[count-1];
1919  assert(last_pc->pc_offset() == PcDesc::upper_offset_limit, "sanity");
1920  last_pc->set_pc_offset(content_size() + 1);
1921  for (; last_pc + 1 < scopes_pcs_end(); last_pc += 1) {
1922    // Fill any rounding gaps with copies of the last record.
1923    last_pc[1] = last_pc[0];
1924  }
1925  // The following assert could fail if sizeof(PcDesc) is not
1926  // an integral multiple of oopSize (the rounding term).
1927  // If it fails, change the logic to always allocate a multiple
1928  // of sizeof(PcDesc), and fill unused words with copies of *last_pc.
1929  assert(last_pc + 1 == scopes_pcs_end(), "must match exactly");
1930}
1931
1932void nmethod::copy_scopes_data(u_char* buffer, int size) {
1933  assert(scopes_data_size() >= size, "oob");
1934  memcpy(scopes_data_begin(), buffer, size);
1935}
1936
1937
1938#ifdef ASSERT
1939static PcDesc* linear_search(nmethod* nm, int pc_offset, bool approximate) {
1940  PcDesc* lower = nm->scopes_pcs_begin();
1941  PcDesc* upper = nm->scopes_pcs_end();
1942  lower += 1; // exclude initial sentinel
1943  PcDesc* res = NULL;
1944  for (PcDesc* p = lower; p < upper; p++) {
1945    NOT_PRODUCT(--nmethod_stats.pc_desc_tests);  // don't count this call to match_desc
1946    if (match_desc(p, pc_offset, approximate)) {
1947      if (res == NULL)
1948        res = p;
1949      else
1950        res = (PcDesc*) badAddress;
1951    }
1952  }
1953  return res;
1954}
1955#endif
1956
1957
1958// Finds a PcDesc with real-pc equal to "pc"
1959PcDesc* nmethod::find_pc_desc_internal(address pc, bool approximate) {
1960  address base_address = code_begin();
1961  if ((pc < base_address) ||
1962      (pc - base_address) >= (ptrdiff_t) PcDesc::upper_offset_limit) {
1963    return NULL;  // PC is wildly out of range
1964  }
1965  int pc_offset = (int) (pc - base_address);
1966
1967  // Check the PcDesc cache if it contains the desired PcDesc
1968  // (This as an almost 100% hit rate.)
1969  PcDesc* res = _pc_desc_cache.find_pc_desc(pc_offset, approximate);
1970  if (res != NULL) {
1971    assert(res == linear_search(this, pc_offset, approximate), "cache ok");
1972    return res;
1973  }
1974
1975  // Fallback algorithm: quasi-linear search for the PcDesc
1976  // Find the last pc_offset less than the given offset.
1977  // The successor must be the required match, if there is a match at all.
1978  // (Use a fixed radix to avoid expensive affine pointer arithmetic.)
1979  PcDesc* lower = scopes_pcs_begin();
1980  PcDesc* upper = scopes_pcs_end();
1981  upper -= 1; // exclude final sentinel
1982  if (lower >= upper)  return NULL;  // native method; no PcDescs at all
1983
1984#define assert_LU_OK \
1985  /* invariant on lower..upper during the following search: */ \
1986  assert(lower->pc_offset() <  pc_offset, "sanity"); \
1987  assert(upper->pc_offset() >= pc_offset, "sanity")
1988  assert_LU_OK;
1989
1990  // Use the last successful return as a split point.
1991  PcDesc* mid = _pc_desc_cache.last_pc_desc();
1992  NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
1993  if (mid->pc_offset() < pc_offset) {
1994    lower = mid;
1995  } else {
1996    upper = mid;
1997  }
1998
1999  // Take giant steps at first (4096, then 256, then 16, then 1)
2000  const int LOG2_RADIX = 4 /*smaller steps in debug mode:*/ debug_only(-1);
2001  const int RADIX = (1 << LOG2_RADIX);
2002  for (int step = (1 << (LOG2_RADIX*3)); step > 1; step >>= LOG2_RADIX) {
2003    while ((mid = lower + step) < upper) {
2004      assert_LU_OK;
2005      NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2006      if (mid->pc_offset() < pc_offset) {
2007        lower = mid;
2008      } else {
2009        upper = mid;
2010        break;
2011      }
2012    }
2013    assert_LU_OK;
2014  }
2015
2016  // Sneak up on the value with a linear search of length ~16.
2017  while (true) {
2018    assert_LU_OK;
2019    mid = lower + 1;
2020    NOT_PRODUCT(++nmethod_stats.pc_desc_searches);
2021    if (mid->pc_offset() < pc_offset) {
2022      lower = mid;
2023    } else {
2024      upper = mid;
2025      break;
2026    }
2027  }
2028#undef assert_LU_OK
2029
2030  if (match_desc(upper, pc_offset, approximate)) {
2031    assert(upper == linear_search(this, pc_offset, approximate), "search ok");
2032    _pc_desc_cache.add_pc_desc(upper);
2033    return upper;
2034  } else {
2035    assert(NULL == linear_search(this, pc_offset, approximate), "search ok");
2036    return NULL;
2037  }
2038}
2039
2040
2041bool nmethod::check_all_dependencies() {
2042  bool found_check = false;
2043  // wholesale check of all dependencies
2044  for (Dependencies::DepStream deps(this); deps.next(); ) {
2045    if (deps.check_dependency() != NULL) {
2046      found_check = true;
2047      NOT_DEBUG(break);
2048    }
2049  }
2050  return found_check;  // tell caller if we found anything
2051}
2052
2053bool nmethod::check_dependency_on(DepChange& changes) {
2054  // What has happened:
2055  // 1) a new class dependee has been added
2056  // 2) dependee and all its super classes have been marked
2057  bool found_check = false;  // set true if we are upset
2058  for (Dependencies::DepStream deps(this); deps.next(); ) {
2059    // Evaluate only relevant dependencies.
2060    if (deps.spot_check_dependency_at(changes) != NULL) {
2061      found_check = true;
2062      NOT_DEBUG(break);
2063    }
2064  }
2065  return found_check;
2066}
2067
2068bool nmethod::is_evol_dependent_on(klassOop dependee) {
2069  instanceKlass *dependee_ik = instanceKlass::cast(dependee);
2070  objArrayOop dependee_methods = dependee_ik->methods();
2071  for (Dependencies::DepStream deps(this); deps.next(); ) {
2072    if (deps.type() == Dependencies::evol_method) {
2073      methodOop method = deps.method_argument(0);
2074      for (int j = 0; j < dependee_methods->length(); j++) {
2075        if ((methodOop) dependee_methods->obj_at(j) == method) {
2076          // RC_TRACE macro has an embedded ResourceMark
2077          RC_TRACE(0x01000000,
2078            ("Found evol dependency of nmethod %s.%s(%s) compile_id=%d on method %s.%s(%s)",
2079            _method->method_holder()->klass_part()->external_name(),
2080            _method->name()->as_C_string(),
2081            _method->signature()->as_C_string(), compile_id(),
2082            method->method_holder()->klass_part()->external_name(),
2083            method->name()->as_C_string(),
2084            method->signature()->as_C_string()));
2085          if (TraceDependencies || LogCompilation)
2086            deps.log_dependency(dependee);
2087          return true;
2088        }
2089      }
2090    }
2091  }
2092  return false;
2093}
2094
2095// Called from mark_for_deoptimization, when dependee is invalidated.
2096bool nmethod::is_dependent_on_method(methodOop dependee) {
2097  for (Dependencies::DepStream deps(this); deps.next(); ) {
2098    if (deps.type() != Dependencies::evol_method)
2099      continue;
2100    methodOop method = deps.method_argument(0);
2101    if (method == dependee) return true;
2102  }
2103  return false;
2104}
2105
2106
2107bool nmethod::is_patchable_at(address instr_addr) {
2108  assert(insts_contains(instr_addr), "wrong nmethod used");
2109  if (is_zombie()) {
2110    // a zombie may never be patched
2111    return false;
2112  }
2113  return true;
2114}
2115
2116
2117address nmethod::continuation_for_implicit_exception(address pc) {
2118  // Exception happened outside inline-cache check code => we are inside
2119  // an active nmethod => use cpc to determine a return address
2120  int exception_offset = pc - code_begin();
2121  int cont_offset = ImplicitExceptionTable(this).at( exception_offset );
2122#ifdef ASSERT
2123  if (cont_offset == 0) {
2124    Thread* thread = ThreadLocalStorage::get_thread_slow();
2125    ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
2126    HandleMark hm(thread);
2127    ResourceMark rm(thread);
2128    CodeBlob* cb = CodeCache::find_blob(pc);
2129    assert(cb != NULL && cb == this, "");
2130    tty->print_cr("implicit exception happened at " INTPTR_FORMAT, pc);
2131    print();
2132    method()->print_codes();
2133    print_code();
2134    print_pcs();
2135  }
2136#endif
2137  if (cont_offset == 0) {
2138    // Let the normal error handling report the exception
2139    return NULL;
2140  }
2141  return code_begin() + cont_offset;
2142}
2143
2144
2145
2146void nmethod_init() {
2147  // make sure you didn't forget to adjust the filler fields
2148  assert(sizeof(nmethod) % oopSize == 0, "nmethod size must be multiple of a word");
2149}
2150
2151
2152//-------------------------------------------------------------------------------------------
2153
2154
2155// QQQ might we make this work from a frame??
2156nmethodLocker::nmethodLocker(address pc) {
2157  CodeBlob* cb = CodeCache::find_blob(pc);
2158  guarantee(cb != NULL && cb->is_nmethod(), "bad pc for a nmethod found");
2159  _nm = (nmethod*)cb;
2160  lock_nmethod(_nm);
2161}
2162
2163// Only JvmtiDeferredEvent::compiled_method_unload_event()
2164// should pass zombie_ok == true.
2165void nmethodLocker::lock_nmethod(nmethod* nm, bool zombie_ok) {
2166  if (nm == NULL)  return;
2167  Atomic::inc(&nm->_lock_count);
2168  guarantee(zombie_ok || !nm->is_zombie(), "cannot lock a zombie method");
2169}
2170
2171void nmethodLocker::unlock_nmethod(nmethod* nm) {
2172  if (nm == NULL)  return;
2173  Atomic::dec(&nm->_lock_count);
2174  guarantee(nm->_lock_count >= 0, "unmatched nmethod lock/unlock");
2175}
2176
2177
2178// -----------------------------------------------------------------------------
2179// nmethod::get_deopt_original_pc
2180//
2181// Return the original PC for the given PC if:
2182// (a) the given PC belongs to a nmethod and
2183// (b) it is a deopt PC
2184address nmethod::get_deopt_original_pc(const frame* fr) {
2185  if (fr->cb() == NULL)  return NULL;
2186
2187  nmethod* nm = fr->cb()->as_nmethod_or_null();
2188  if (nm != NULL && nm->is_deopt_pc(fr->pc()))
2189    return nm->get_original_pc(fr);
2190
2191  return NULL;
2192}
2193
2194
2195// -----------------------------------------------------------------------------
2196// MethodHandle
2197
2198bool nmethod::is_method_handle_return(address return_pc) {
2199  if (!has_method_handle_invokes())  return false;
2200  PcDesc* pd = pc_desc_at(return_pc);
2201  if (pd == NULL)
2202    return false;
2203  return pd->is_method_handle_invoke();
2204}
2205
2206
2207// -----------------------------------------------------------------------------
2208// Verification
2209
2210class VerifyOopsClosure: public OopClosure {
2211  nmethod* _nm;
2212  bool     _ok;
2213public:
2214  VerifyOopsClosure(nmethod* nm) : _nm(nm), _ok(true) { }
2215  bool ok() { return _ok; }
2216  virtual void do_oop(oop* p) {
2217    if ((*p) == NULL || (*p)->is_oop())  return;
2218    if (_ok) {
2219      _nm->print_nmethod(true);
2220      _ok = false;
2221    }
2222    tty->print_cr("*** non-oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2223                  (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2224  }
2225  virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2226};
2227
2228void nmethod::verify() {
2229
2230  // Hmm. OSR methods can be deopted but not marked as zombie or not_entrant
2231  // seems odd.
2232
2233  if( is_zombie() || is_not_entrant() )
2234    return;
2235
2236  // Make sure all the entry points are correctly aligned for patching.
2237  NativeJump::check_verified_entry_alignment(entry_point(), verified_entry_point());
2238
2239  assert(method()->is_oop(), "must be valid");
2240
2241  ResourceMark rm;
2242
2243  if (!CodeCache::contains(this)) {
2244    fatal(err_msg("nmethod at " INTPTR_FORMAT " not in zone", this));
2245  }
2246
2247  if(is_native_method() )
2248    return;
2249
2250  nmethod* nm = CodeCache::find_nmethod(verified_entry_point());
2251  if (nm != this) {
2252    fatal(err_msg("findNMethod did not find this nmethod (" INTPTR_FORMAT ")",
2253                  this));
2254  }
2255
2256  for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2257    if (! p->verify(this)) {
2258      tty->print_cr("\t\tin nmethod at " INTPTR_FORMAT " (pcs)", this);
2259    }
2260  }
2261
2262  VerifyOopsClosure voc(this);
2263  oops_do(&voc);
2264  assert(voc.ok(), "embedded oops must be OK");
2265  verify_scavenge_root_oops();
2266
2267  verify_scopes();
2268}
2269
2270
2271void nmethod::verify_interrupt_point(address call_site) {
2272  // This code does not work in release mode since
2273  // owns_lock only is available in debug mode.
2274  CompiledIC* ic = NULL;
2275  Thread *cur = Thread::current();
2276  if (CompiledIC_lock->owner() == cur ||
2277      ((cur->is_VM_thread() || cur->is_ConcurrentGC_thread()) &&
2278       SafepointSynchronize::is_at_safepoint())) {
2279    ic = CompiledIC_at(call_site);
2280    CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
2281  } else {
2282    MutexLocker ml_verify (CompiledIC_lock);
2283    ic = CompiledIC_at(call_site);
2284  }
2285  PcDesc* pd = pc_desc_at(ic->end_of_call());
2286  assert(pd != NULL, "PcDesc must exist");
2287  for (ScopeDesc* sd = new ScopeDesc(this, pd->scope_decode_offset(),
2288                                     pd->obj_decode_offset(), pd->should_reexecute(),
2289                                     pd->return_oop());
2290       !sd->is_top(); sd = sd->sender()) {
2291    sd->verify();
2292  }
2293}
2294
2295void nmethod::verify_scopes() {
2296  if( !method() ) return;       // Runtime stubs have no scope
2297  if (method()->is_native()) return; // Ignore stub methods.
2298  // iterate through all interrupt point
2299  // and verify the debug information is valid.
2300  RelocIterator iter((nmethod*)this);
2301  while (iter.next()) {
2302    address stub = NULL;
2303    switch (iter.type()) {
2304      case relocInfo::virtual_call_type:
2305        verify_interrupt_point(iter.addr());
2306        break;
2307      case relocInfo::opt_virtual_call_type:
2308        stub = iter.opt_virtual_call_reloc()->static_stub();
2309        verify_interrupt_point(iter.addr());
2310        break;
2311      case relocInfo::static_call_type:
2312        stub = iter.static_call_reloc()->static_stub();
2313        //verify_interrupt_point(iter.addr());
2314        break;
2315      case relocInfo::runtime_call_type:
2316        address destination = iter.reloc()->value();
2317        // Right now there is no way to find out which entries support
2318        // an interrupt point.  It would be nice if we had this
2319        // information in a table.
2320        break;
2321    }
2322    assert(stub == NULL || stub_contains(stub), "static call stub outside stub section");
2323  }
2324}
2325
2326
2327// -----------------------------------------------------------------------------
2328// Non-product code
2329#ifndef PRODUCT
2330
2331class DebugScavengeRoot: public OopClosure {
2332  nmethod* _nm;
2333  bool     _ok;
2334public:
2335  DebugScavengeRoot(nmethod* nm) : _nm(nm), _ok(true) { }
2336  bool ok() { return _ok; }
2337  virtual void do_oop(oop* p) {
2338    if ((*p) == NULL || !(*p)->is_scavengable())  return;
2339    if (_ok) {
2340      _nm->print_nmethod(true);
2341      _ok = false;
2342    }
2343    tty->print_cr("*** scavengable oop "PTR_FORMAT" found at "PTR_FORMAT" (offset %d)",
2344                  (intptr_t)(*p), (intptr_t)p, (int)((intptr_t)p - (intptr_t)_nm));
2345    (*p)->print();
2346  }
2347  virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); }
2348};
2349
2350void nmethod::verify_scavenge_root_oops() {
2351  if (!on_scavenge_root_list()) {
2352    // Actually look inside, to verify the claim that it's clean.
2353    DebugScavengeRoot debug_scavenge_root(this);
2354    oops_do(&debug_scavenge_root);
2355    if (!debug_scavenge_root.ok())
2356      fatal("found an unadvertised bad scavengable oop in the code cache");
2357  }
2358  assert(scavenge_root_not_marked(), "");
2359}
2360
2361#endif // PRODUCT
2362
2363// Printing operations
2364
2365void nmethod::print() const {
2366  ResourceMark rm;
2367  ttyLocker ttyl;   // keep the following output all in one block
2368
2369  tty->print("Compiled method ");
2370
2371  if (is_compiled_by_c1()) {
2372    tty->print("(c1) ");
2373  } else if (is_compiled_by_c2()) {
2374    tty->print("(c2) ");
2375  } else if (is_compiled_by_shark()) {
2376    tty->print("(shark) ");
2377  } else {
2378    tty->print("(nm) ");
2379  }
2380
2381  print_on(tty, NULL);
2382
2383  if (WizardMode) {
2384    tty->print("((nmethod*) "INTPTR_FORMAT ") ", this);
2385    tty->print(" for method " INTPTR_FORMAT , (address)method());
2386    tty->print(" { ");
2387    if (is_in_use())      tty->print("in_use ");
2388    if (is_not_entrant()) tty->print("not_entrant ");
2389    if (is_zombie())      tty->print("zombie ");
2390    if (is_unloaded())    tty->print("unloaded ");
2391    if (on_scavenge_root_list())  tty->print("scavenge_root ");
2392    tty->print_cr("}:");
2393  }
2394  if (size              () > 0) tty->print_cr(" total in heap  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2395                                              (address)this,
2396                                              (address)this + size(),
2397                                              size());
2398  if (relocation_size   () > 0) tty->print_cr(" relocation     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2399                                              relocation_begin(),
2400                                              relocation_end(),
2401                                              relocation_size());
2402  if (consts_size       () > 0) tty->print_cr(" constants      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2403                                              consts_begin(),
2404                                              consts_end(),
2405                                              consts_size());
2406  if (insts_size        () > 0) tty->print_cr(" main code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2407                                              insts_begin(),
2408                                              insts_end(),
2409                                              insts_size());
2410  if (stub_size         () > 0) tty->print_cr(" stub code      [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2411                                              stub_begin(),
2412                                              stub_end(),
2413                                              stub_size());
2414  if (oops_size         () > 0) tty->print_cr(" oops           [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2415                                              oops_begin(),
2416                                              oops_end(),
2417                                              oops_size());
2418  if (scopes_data_size  () > 0) tty->print_cr(" scopes data    [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2419                                              scopes_data_begin(),
2420                                              scopes_data_end(),
2421                                              scopes_data_size());
2422  if (scopes_pcs_size   () > 0) tty->print_cr(" scopes pcs     [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2423                                              scopes_pcs_begin(),
2424                                              scopes_pcs_end(),
2425                                              scopes_pcs_size());
2426  if (dependencies_size () > 0) tty->print_cr(" dependencies   [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2427                                              dependencies_begin(),
2428                                              dependencies_end(),
2429                                              dependencies_size());
2430  if (handler_table_size() > 0) tty->print_cr(" handler table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2431                                              handler_table_begin(),
2432                                              handler_table_end(),
2433                                              handler_table_size());
2434  if (nul_chk_table_size() > 0) tty->print_cr(" nul chk table  [" INTPTR_FORMAT "," INTPTR_FORMAT "] = %d",
2435                                              nul_chk_table_begin(),
2436                                              nul_chk_table_end(),
2437                                              nul_chk_table_size());
2438}
2439
2440void nmethod::print_code() {
2441  HandleMark hm;
2442  ResourceMark m;
2443  Disassembler::decode(this);
2444}
2445
2446
2447#ifndef PRODUCT
2448
2449void nmethod::print_scopes() {
2450  // Find the first pc desc for all scopes in the code and print it.
2451  ResourceMark rm;
2452  for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2453    if (p->scope_decode_offset() == DebugInformationRecorder::serialized_null)
2454      continue;
2455
2456    ScopeDesc* sd = scope_desc_at(p->real_pc(this));
2457    sd->print_on(tty, p);
2458  }
2459}
2460
2461void nmethod::print_dependencies() {
2462  ResourceMark rm;
2463  ttyLocker ttyl;   // keep the following output all in one block
2464  tty->print_cr("Dependencies:");
2465  for (Dependencies::DepStream deps(this); deps.next(); ) {
2466    deps.print_dependency();
2467    klassOop ctxk = deps.context_type();
2468    if (ctxk != NULL) {
2469      Klass* k = Klass::cast(ctxk);
2470      if (k->oop_is_instance() && ((instanceKlass*)k)->is_dependent_nmethod(this)) {
2471        tty->print_cr("   [nmethod<=klass]%s", k->external_name());
2472      }
2473    }
2474    deps.log_dependency();  // put it into the xml log also
2475  }
2476}
2477
2478
2479void nmethod::print_relocations() {
2480  ResourceMark m;       // in case methods get printed via the debugger
2481  tty->print_cr("relocations:");
2482  RelocIterator iter(this);
2483  iter.print();
2484  if (UseRelocIndex) {
2485    jint* index_end   = (jint*)relocation_end() - 1;
2486    jint  index_size  = *index_end;
2487    jint* index_start = (jint*)( (address)index_end - index_size );
2488    tty->print_cr("    index @" INTPTR_FORMAT ": index_size=%d", index_start, index_size);
2489    if (index_size > 0) {
2490      jint* ip;
2491      for (ip = index_start; ip+2 <= index_end; ip += 2)
2492        tty->print_cr("  (%d %d) addr=" INTPTR_FORMAT " @" INTPTR_FORMAT,
2493                      ip[0],
2494                      ip[1],
2495                      header_end()+ip[0],
2496                      relocation_begin()-1+ip[1]);
2497      for (; ip < index_end; ip++)
2498        tty->print_cr("  (%d ?)", ip[0]);
2499      tty->print_cr("          @" INTPTR_FORMAT ": index_size=%d", ip, *ip++);
2500      tty->print_cr("reloc_end @" INTPTR_FORMAT ":", ip);
2501    }
2502  }
2503}
2504
2505
2506void nmethod::print_pcs() {
2507  ResourceMark m;       // in case methods get printed via debugger
2508  tty->print_cr("pc-bytecode offsets:");
2509  for (PcDesc* p = scopes_pcs_begin(); p < scopes_pcs_end(); p++) {
2510    p->print(this);
2511  }
2512}
2513
2514#endif // PRODUCT
2515
2516const char* nmethod::reloc_string_for(u_char* begin, u_char* end) {
2517  RelocIterator iter(this, begin, end);
2518  bool have_one = false;
2519  while (iter.next()) {
2520    have_one = true;
2521    switch (iter.type()) {
2522        case relocInfo::none:                  return "no_reloc";
2523        case relocInfo::oop_type: {
2524          stringStream st;
2525          oop_Relocation* r = iter.oop_reloc();
2526          oop obj = r->oop_value();
2527          st.print("oop(");
2528          if (obj == NULL) st.print("NULL");
2529          else obj->print_value_on(&st);
2530          st.print(")");
2531          return st.as_string();
2532        }
2533        case relocInfo::virtual_call_type:     return "virtual_call";
2534        case relocInfo::opt_virtual_call_type: return "optimized virtual_call";
2535        case relocInfo::static_call_type:      return "static_call";
2536        case relocInfo::static_stub_type:      return "static_stub";
2537        case relocInfo::runtime_call_type:     return "runtime_call";
2538        case relocInfo::external_word_type:    return "external_word";
2539        case relocInfo::internal_word_type:    return "internal_word";
2540        case relocInfo::section_word_type:     return "section_word";
2541        case relocInfo::poll_type:             return "poll";
2542        case relocInfo::poll_return_type:      return "poll_return";
2543        case relocInfo::type_mask:             return "type_bit_mask";
2544    }
2545  }
2546  return have_one ? "other" : NULL;
2547}
2548
2549// Return a the last scope in (begin..end]
2550ScopeDesc* nmethod::scope_desc_in(address begin, address end) {
2551  PcDesc* p = pc_desc_near(begin+1);
2552  if (p != NULL && p->real_pc(this) <= end) {
2553    return new ScopeDesc(this, p->scope_decode_offset(),
2554                         p->obj_decode_offset(), p->should_reexecute(),
2555                         p->return_oop());
2556  }
2557  return NULL;
2558}
2559
2560void nmethod::print_nmethod_labels(outputStream* stream, address block_begin) {
2561  if (block_begin == entry_point())             stream->print_cr("[Entry Point]");
2562  if (block_begin == verified_entry_point())    stream->print_cr("[Verified Entry Point]");
2563  if (block_begin == exception_begin())         stream->print_cr("[Exception Handler]");
2564  if (block_begin == stub_begin())              stream->print_cr("[Stub Code]");
2565  if (block_begin == deopt_handler_begin())     stream->print_cr("[Deopt Handler Code]");
2566
2567  if (has_method_handle_invokes())
2568    if (block_begin == deopt_mh_handler_begin())  stream->print_cr("[Deopt MH Handler Code]");
2569
2570  if (block_begin == consts_begin())            stream->print_cr("[Constants]");
2571
2572  if (block_begin == entry_point()) {
2573    methodHandle m = method();
2574    if (m.not_null()) {
2575      stream->print("  # ");
2576      m->print_value_on(stream);
2577      stream->cr();
2578    }
2579    if (m.not_null() && !is_osr_method()) {
2580      ResourceMark rm;
2581      int sizeargs = m->size_of_parameters();
2582      BasicType* sig_bt = NEW_RESOURCE_ARRAY(BasicType, sizeargs);
2583      VMRegPair* regs   = NEW_RESOURCE_ARRAY(VMRegPair, sizeargs);
2584      {
2585        int sig_index = 0;
2586        if (!m->is_static())
2587          sig_bt[sig_index++] = T_OBJECT; // 'this'
2588        for (SignatureStream ss(m->signature()); !ss.at_return_type(); ss.next()) {
2589          BasicType t = ss.type();
2590          sig_bt[sig_index++] = t;
2591          if (type2size[t] == 2) {
2592            sig_bt[sig_index++] = T_VOID;
2593          } else {
2594            assert(type2size[t] == 1, "size is 1 or 2");
2595          }
2596        }
2597        assert(sig_index == sizeargs, "");
2598      }
2599      const char* spname = "sp"; // make arch-specific?
2600      intptr_t out_preserve = SharedRuntime::java_calling_convention(sig_bt, regs, sizeargs, false);
2601      int stack_slot_offset = this->frame_size() * wordSize;
2602      int tab1 = 14, tab2 = 24;
2603      int sig_index = 0;
2604      int arg_index = (m->is_static() ? 0 : -1);
2605      bool did_old_sp = false;
2606      for (SignatureStream ss(m->signature()); !ss.at_return_type(); ) {
2607        bool at_this = (arg_index == -1);
2608        bool at_old_sp = false;
2609        BasicType t = (at_this ? T_OBJECT : ss.type());
2610        assert(t == sig_bt[sig_index], "sigs in sync");
2611        if (at_this)
2612          stream->print("  # this: ");
2613        else
2614          stream->print("  # parm%d: ", arg_index);
2615        stream->move_to(tab1);
2616        VMReg fst = regs[sig_index].first();
2617        VMReg snd = regs[sig_index].second();
2618        if (fst->is_reg()) {
2619          stream->print("%s", fst->name());
2620          if (snd->is_valid())  {
2621            stream->print(":%s", snd->name());
2622          }
2623        } else if (fst->is_stack()) {
2624          int offset = fst->reg2stack() * VMRegImpl::stack_slot_size + stack_slot_offset;
2625          if (offset == stack_slot_offset)  at_old_sp = true;
2626          stream->print("[%s+0x%x]", spname, offset);
2627        } else {
2628          stream->print("reg%d:%d??", (int)(intptr_t)fst, (int)(intptr_t)snd);
2629        }
2630        stream->print(" ");
2631        stream->move_to(tab2);
2632        stream->print("= ");
2633        if (at_this) {
2634          m->method_holder()->print_value_on(stream);
2635        } else {
2636          bool did_name = false;
2637          if (!at_this && ss.is_object()) {
2638            Symbol* name = ss.as_symbol_or_null();
2639            if (name != NULL) {
2640              name->print_value_on(stream);
2641              did_name = true;
2642            }
2643          }
2644          if (!did_name)
2645            stream->print("%s", type2name(t));
2646        }
2647        if (at_old_sp) {
2648          stream->print("  (%s of caller)", spname);
2649          did_old_sp = true;
2650        }
2651        stream->cr();
2652        sig_index += type2size[t];
2653        arg_index += 1;
2654        if (!at_this)  ss.next();
2655      }
2656      if (!did_old_sp) {
2657        stream->print("  # ");
2658        stream->move_to(tab1);
2659        stream->print("[%s+0x%x]", spname, stack_slot_offset);
2660        stream->print("  (%s of caller)", spname);
2661        stream->cr();
2662      }
2663    }
2664  }
2665}
2666
2667void nmethod::print_code_comment_on(outputStream* st, int column, u_char* begin, u_char* end) {
2668  // First, find an oopmap in (begin, end].
2669  // We use the odd half-closed interval so that oop maps and scope descs
2670  // which are tied to the byte after a call are printed with the call itself.
2671  address base = code_begin();
2672  OopMapSet* oms = oop_maps();
2673  if (oms != NULL) {
2674    for (int i = 0, imax = oms->size(); i < imax; i++) {
2675      OopMap* om = oms->at(i);
2676      address pc = base + om->offset();
2677      if (pc > begin) {
2678        if (pc <= end) {
2679          st->move_to(column);
2680          st->print("; ");
2681          om->print_on(st);
2682        }
2683        break;
2684      }
2685    }
2686  }
2687
2688  // Print any debug info present at this pc.
2689  ScopeDesc* sd  = scope_desc_in(begin, end);
2690  if (sd != NULL) {
2691    st->move_to(column);
2692    if (sd->bci() == SynchronizationEntryBCI) {
2693      st->print(";*synchronization entry");
2694    } else {
2695      if (sd->method().is_null()) {
2696        st->print("method is NULL");
2697      } else if (sd->method()->is_native()) {
2698        st->print("method is native");
2699      } else {
2700        Bytecodes::Code bc = sd->method()->java_code_at(sd->bci());
2701        st->print(";*%s", Bytecodes::name(bc));
2702        switch (bc) {
2703        case Bytecodes::_invokevirtual:
2704        case Bytecodes::_invokespecial:
2705        case Bytecodes::_invokestatic:
2706        case Bytecodes::_invokeinterface:
2707          {
2708            Bytecode_invoke invoke(sd->method(), sd->bci());
2709            st->print(" ");
2710            if (invoke.name() != NULL)
2711              invoke.name()->print_symbol_on(st);
2712            else
2713              st->print("<UNKNOWN>");
2714            break;
2715          }
2716        case Bytecodes::_getfield:
2717        case Bytecodes::_putfield:
2718        case Bytecodes::_getstatic:
2719        case Bytecodes::_putstatic:
2720          {
2721            Bytecode_field field(sd->method(), sd->bci());
2722            st->print(" ");
2723            if (field.name() != NULL)
2724              field.name()->print_symbol_on(st);
2725            else
2726              st->print("<UNKNOWN>");
2727          }
2728        }
2729      }
2730    }
2731
2732    // Print all scopes
2733    for (;sd != NULL; sd = sd->sender()) {
2734      st->move_to(column);
2735      st->print("; -");
2736      if (sd->method().is_null()) {
2737        st->print("method is NULL");
2738      } else {
2739        sd->method()->print_short_name(st);
2740      }
2741      int lineno = sd->method()->line_number_from_bci(sd->bci());
2742      if (lineno != -1) {
2743        st->print("@%d (line %d)", sd->bci(), lineno);
2744      } else {
2745        st->print("@%d", sd->bci());
2746      }
2747      st->cr();
2748    }
2749  }
2750
2751  // Print relocation information
2752  const char* str = reloc_string_for(begin, end);
2753  if (str != NULL) {
2754    if (sd != NULL) st->cr();
2755    st->move_to(column);
2756    st->print(";   {%s}", str);
2757  }
2758  int cont_offset = ImplicitExceptionTable(this).at(begin - code_begin());
2759  if (cont_offset != 0) {
2760    st->move_to(column);
2761    st->print("; implicit exception: dispatches to " INTPTR_FORMAT, code_begin() + cont_offset);
2762  }
2763
2764}
2765
2766#ifndef PRODUCT
2767
2768void nmethod::print_value_on(outputStream* st) const {
2769  st->print("nmethod");
2770  print_on(st, NULL);
2771}
2772
2773void nmethod::print_calls(outputStream* st) {
2774  RelocIterator iter(this);
2775  while (iter.next()) {
2776    switch (iter.type()) {
2777    case relocInfo::virtual_call_type:
2778    case relocInfo::opt_virtual_call_type: {
2779      VerifyMutexLocker mc(CompiledIC_lock);
2780      CompiledIC_at(iter.reloc())->print();
2781      break;
2782    }
2783    case relocInfo::static_call_type:
2784      st->print_cr("Static call at " INTPTR_FORMAT, iter.reloc()->addr());
2785      compiledStaticCall_at(iter.reloc())->print();
2786      break;
2787    }
2788  }
2789}
2790
2791void nmethod::print_handler_table() {
2792  ExceptionHandlerTable(this).print();
2793}
2794
2795void nmethod::print_nul_chk_table() {
2796  ImplicitExceptionTable(this).print(code_begin());
2797}
2798
2799void nmethod::print_statistics() {
2800  ttyLocker ttyl;
2801  if (xtty != NULL)  xtty->head("statistics type='nmethod'");
2802  nmethod_stats.print_native_nmethod_stats();
2803  nmethod_stats.print_nmethod_stats();
2804  DebugInformationRecorder::print_statistics();
2805  nmethod_stats.print_pc_stats();
2806  Dependencies::print_statistics();
2807  if (xtty != NULL)  xtty->tail("statistics");
2808}
2809
2810#endif // PRODUCT
2811