1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
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  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  *
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 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 24 
 25 #ifndef SHARE_CODE_NMETHOD_HPP
 26 #define SHARE_CODE_NMETHOD_HPP
 27 
 28 #include "code/compiledMethod.hpp"
 29 
 30 class CompiledICData;
 31 class CompileTask;
 32 class DepChange;
 33 class DirectiveSet;
 34 class DebugInformationRecorder;
 35 class JvmtiThreadState;
 36 class OopIterateClosure;
 37 
 38 // nmethods (native methods) are the compiled code versions of Java methods.
 39 //
 40 // An nmethod contains:
 41 //  - header                 (the nmethod structure)
 42 //  [Relocation]
 43 //  - relocation information
 44 //  - constant part          (doubles, longs and floats used in nmethod)
 45 //  - oop table
 46 //  [Code]
 47 //  - code body
 48 //  - exception handler
 49 //  - stub code
 50 //  [Debugging information]
 51 //  - oop array
 52 //  - data array
 53 //  - pcs
 54 //  [Exception handler table]
 55 //  - handler entry point array
 56 //  [Implicit Null Pointer exception table]
 57 //  - implicit null table array
 58 //  [Speculations]
 59 //  - encoded speculations array
 60 //  [JVMCINMethodData]
 61 //  - meta data for JVMCI compiled nmethod
 62 
 63 #if INCLUDE_JVMCI
 64 class FailedSpeculation;
 65 class JVMCINMethodData;
 66 #endif
 67 
 68 class nmethod : public CompiledMethod {
 69   friend class VMStructs;
 70   friend class JVMCIVMStructs;
 71   friend class CodeCache;  // scavengable oops
 72   friend class JVMCINMethodData;
 73 
 74  private:
 75 
 76   uint64_t  _gc_epoch;
 77 
 78   // To support simple linked-list chaining of nmethods:
 79   nmethod*  _osr_link;         // from InstanceKlass::osr_nmethods_head
 80 
 81   // STW two-phase nmethod root processing helpers.
 82   //
 83   // When determining liveness of a given nmethod to do code cache unloading,
 84   // some collectors need to do different things depending on whether the nmethods
 85   // need to absolutely be kept alive during root processing; "strong"ly reachable
 86   // nmethods are known to be kept alive at root processing, but the liveness of
 87   // "weak"ly reachable ones is to be determined later.
 88   //
 89   // We want to allow strong and weak processing of nmethods by different threads
 90   // at the same time without heavy synchronization. Additional constraints are
 91   // to make sure that every nmethod is processed a minimal amount of time, and
 92   // nmethods themselves are always iterated at most once at a particular time.
 93   //
 94   // Note that strong processing work must be a superset of weak processing work
 95   // for this code to work.
 96   //
 97   // We store state and claim information in the _oops_do_mark_link member, using
 98   // the two LSBs for the state and the remaining upper bits for linking together
 99   // nmethods that were already visited.
100   // The last element is self-looped, i.e. points to itself to avoid some special
101   // "end-of-list" sentinel value.
102   //
103   // _oops_do_mark_link special values:
104   //
105   //   _oops_do_mark_link == nullptr: the nmethod has not been visited at all yet, i.e.
106   //      is Unclaimed.
107   //
108   // For other values, its lowest two bits indicate the following states of the nmethod:
109   //
110   //   weak_request (WR): the nmethod has been claimed by a thread for weak processing
111   //   weak_done (WD): weak processing has been completed for this nmethod.
112   //   strong_request (SR): the nmethod has been found to need strong processing while
113   //       being weak processed.
114   //   strong_done (SD): strong processing has been completed for this nmethod .
115   //
116   // The following shows the _only_ possible progressions of the _oops_do_mark_link
117   // pointer.
118   //
119   // Given
120   //   N as the nmethod
121   //   X the current next value of _oops_do_mark_link
122   //
123   // Unclaimed (C)-> N|WR (C)-> X|WD: the nmethod has been processed weakly by
124   //   a single thread.
125   // Unclaimed (C)-> N|WR (C)-> X|WD (O)-> X|SD: after weak processing has been
126   //   completed (as above) another thread found that the nmethod needs strong
127   //   processing after all.
128   // Unclaimed (C)-> N|WR (O)-> N|SR (C)-> X|SD: during weak processing another
129   //   thread finds that the nmethod needs strong processing, marks it as such and
130   //   terminates. The original thread completes strong processing.
131   // Unclaimed (C)-> N|SD (C)-> X|SD: the nmethod has been processed strongly from
132   //   the beginning by a single thread.
133   //
134   // "|" describes the concatenation of bits in _oops_do_mark_link.
135   //
136   // The diagram also describes the threads responsible for changing the nmethod to
137   // the next state by marking the _transition_ with (C) and (O), which mean "current"
138   // and "other" thread respectively.
139   //
140   struct oops_do_mark_link; // Opaque data type.
141 
142   // States used for claiming nmethods during root processing.
143   static const uint claim_weak_request_tag = 0;
144   static const uint claim_weak_done_tag = 1;
145   static const uint claim_strong_request_tag = 2;
146   static const uint claim_strong_done_tag = 3;
147 
148   static oops_do_mark_link* mark_link(nmethod* nm, uint tag) {
149     assert(tag <= claim_strong_done_tag, "invalid tag %u", tag);
150     assert(is_aligned(nm, 4), "nmethod pointer must have zero lower two LSB");
151     return (oops_do_mark_link*)(((uintptr_t)nm & ~0x3) | tag);
152   }
153 
154   static uint extract_state(oops_do_mark_link* link) {
155     return (uint)((uintptr_t)link & 0x3);
156   }
157 
158   static nmethod* extract_nmethod(oops_do_mark_link* link) {
159     return (nmethod*)((uintptr_t)link & ~0x3);
160   }
161 
162   void oops_do_log_change(const char* state);
163 
164   static bool oops_do_has_weak_request(oops_do_mark_link* next) {
165     return extract_state(next) == claim_weak_request_tag;
166   }
167 
168   static bool oops_do_has_any_strong_state(oops_do_mark_link* next) {
169     return extract_state(next) >= claim_strong_request_tag;
170   }
171 
172   // Attempt Unclaimed -> N|WR transition. Returns true if successful.
173   bool oops_do_try_claim_weak_request();
174 
175   // Attempt Unclaimed -> N|SD transition. Returns the current link.
176   oops_do_mark_link* oops_do_try_claim_strong_done();
177   // Attempt N|WR -> X|WD transition. Returns nullptr if successful, X otherwise.
178   nmethod* oops_do_try_add_to_list_as_weak_done();
179 
180   // Attempt X|WD -> N|SR transition. Returns the current link.
181   oops_do_mark_link* oops_do_try_add_strong_request(oops_do_mark_link* next);
182   // Attempt X|WD -> X|SD transition. Returns true if successful.
183   bool oops_do_try_claim_weak_done_as_strong_done(oops_do_mark_link* next);
184 
185   // Do the N|SD -> X|SD transition.
186   void oops_do_add_to_list_as_strong_done();
187 
188   // Sets this nmethod as strongly claimed (as part of N|SD -> X|SD and N|SR -> X|SD
189   // transitions).
190   void oops_do_set_strong_done(nmethod* old_head);
191 
192   static nmethod* volatile _oops_do_mark_nmethods;
193   oops_do_mark_link* volatile _oops_do_mark_link;
194 
195   // offsets for entry points
196   address _entry_point;                      // entry point with class check
197   address _verified_entry_point;             // entry point without class check
198   address _osr_entry_point;                  // entry point for on stack replacement
199 
200   CompiledICData* _compiled_ic_data;
201   bool _is_unlinked;
202 
203   // Shared fields for all nmethod's
204   int _entry_bci;      // != InvocationEntryBci if this nmethod is an on-stack replacement method
205 
206   // Offsets for different nmethod parts
207   int  _exception_offset;
208   // Offset of the unwind handler if it exists
209   int _unwind_handler_offset;
210 
211   int _consts_offset;
212   int _stub_offset;
213   int _oops_offset;                       // offset to where embedded oop table begins (inside data)
214   int _metadata_offset;                   // embedded meta data table
215   int _scopes_data_offset;
216   int _scopes_pcs_offset;
217   int _dependencies_offset;
218   int _handler_table_offset;
219   int _nul_chk_table_offset;
220 #if INCLUDE_JVMCI
221   int _speculations_offset;
222   int _jvmci_data_offset;
223 #endif
224   int _nmethod_end_offset;
225 
226   int code_offset() const { return int(code_begin() - header_begin()); }
227 
228   // location in frame (offset for sp) that deopt can store the original
229   // pc during a deopt.
230   int _orig_pc_offset;
231 
232   int _compile_id;                           // which compilation made this nmethod
233 
234 #if INCLUDE_RTM_OPT
235   // RTM state at compile time. Used during deoptimization to decide
236   // whether to restart collecting RTM locking abort statistic again.
237   RTMState _rtm_state;
238 #endif
239 
240   // These are used for compiled synchronized native methods to
241   // locate the owner and stack slot for the BasicLock. They are
242   // needed because there is no debug information for compiled native
243   // wrappers and the oop maps are insufficient to allow
244   // frame::retrieve_receiver() to work. Currently they are expected
245   // to be byte offsets from the Java stack pointer for maximum code
246   // sharing between platforms. JVMTI's GetLocalInstance() uses these
247   // offsets to find the receiver for non-static native wrapper frames.
248   ByteSize _native_receiver_sp_offset;
249   ByteSize _native_basic_lock_sp_offset;
250 
251   CompLevel _comp_level;               // compilation level
252 
253   // Local state used to keep track of whether unloading is happening or not
254   volatile uint8_t _is_unloading_state;
255 
256   // protected by CodeCache_lock
257   bool _has_flushed_dependencies;      // Used for maintenance of dependencies (CodeCache_lock)
258 
259   // used by jvmti to track if an event has been posted for this nmethod.
260   bool _load_reported;
261 
262   // Protected by CompiledMethod_lock
263   volatile signed char _state;         // {not_installed, in_use, not_used, not_entrant}
264 
265   int _skipped_instructions_size;
266 
267   // For native wrappers
268   nmethod(Method* method,
269           CompilerType type,
270           int nmethod_size,
271           int compile_id,
272           CodeOffsets* offsets,
273           CodeBuffer *code_buffer,
274           int frame_size,
275           ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */
276           ByteSize basic_lock_sp_offset,       /* synchronized natives only */
277           OopMapSet* oop_maps);
278 
279   // Creation support
280   nmethod(Method* method,
281           CompilerType type,
282           int nmethod_size,
283           int compile_id,
284           int entry_bci,
285           CodeOffsets* offsets,
286           int orig_pc_offset,
287           DebugInformationRecorder *recorder,
288           Dependencies* dependencies,
289           CodeBuffer *code_buffer,
290           int frame_size,
291           OopMapSet* oop_maps,
292           ExceptionHandlerTable* handler_table,
293           ImplicitExceptionTable* nul_chk_table,
294           AbstractCompiler* compiler,
295           CompLevel comp_level
296 #if INCLUDE_JVMCI
297           , char* speculations = nullptr,
298           int speculations_len = 0,
299           JVMCINMethodData* jvmci_data = nullptr
300 #endif
301           );
302 
303   // helper methods
304   void* operator new(size_t size, int nmethod_size, int comp_level) throw();
305   // For method handle intrinsics: Try MethodNonProfiled, MethodProfiled and NonNMethod.
306   // Attention: Only allow NonNMethod space for special nmethods which don't need to be
307   // findable by nmethod iterators! In particular, they must not contain oops!
308   void* operator new(size_t size, int nmethod_size, bool allow_NonNMethod_space) throw();
309 
310   const char* reloc_string_for(u_char* begin, u_char* end);
311 
312   bool try_transition(signed char new_state);
313 
314   // Returns true if this thread changed the state of the nmethod or
315   // false if another thread performed the transition.
316   bool make_entrant() { Unimplemented(); return false; }
317   void inc_decompile_count();
318 
319   // Inform external interfaces that a compiled method has been unloaded
320   void post_compiled_method_unload();
321 
322   // Initialize fields to their default values
323   void init_defaults();
324 
325   // Offsets
326   int content_offset() const                  { return int(content_begin() - header_begin()); }
327   int data_offset() const                     { return _data_offset; }
328 
329   address header_end() const                  { return (address)    header_begin() + header_size(); }
330 
331  public:
332   // create nmethod with entry_bci
333   static nmethod* new_nmethod(const methodHandle& method,
334                               int compile_id,
335                               int entry_bci,
336                               CodeOffsets* offsets,
337                               int orig_pc_offset,
338                               DebugInformationRecorder* recorder,
339                               Dependencies* dependencies,
340                               CodeBuffer *code_buffer,
341                               int frame_size,
342                               OopMapSet* oop_maps,
343                               ExceptionHandlerTable* handler_table,
344                               ImplicitExceptionTable* nul_chk_table,
345                               AbstractCompiler* compiler,
346                               CompLevel comp_level
347 #if INCLUDE_JVMCI
348                               , char* speculations = nullptr,
349                               int speculations_len = 0,
350                               JVMCINMethodData* jvmci_data = nullptr
351 #endif
352   );
353 
354   // Only used for unit tests.
355   nmethod()
356     : CompiledMethod(),
357       _native_receiver_sp_offset(in_ByteSize(-1)),
358       _native_basic_lock_sp_offset(in_ByteSize(-1)),
359       _is_unloading_state(0) {}
360 
361 
362   static nmethod* new_native_nmethod(const methodHandle& method,
363                                      int compile_id,
364                                      CodeBuffer *code_buffer,
365                                      int vep_offset,
366                                      int frame_complete,
367                                      int frame_size,
368                                      ByteSize receiver_sp_offset,
369                                      ByteSize basic_lock_sp_offset,
370                                      OopMapSet* oop_maps,
371                                      int exception_handler = -1);
372 
373   // type info
374   bool is_nmethod() const                         { return true; }
375   bool is_osr_method() const                      { return _entry_bci != InvocationEntryBci; }
376 
377   // boundaries for different parts
378   address consts_begin          () const          { return           header_begin() + _consts_offset        ; }
379   address consts_end            () const          { return           code_begin()                           ; }
380   address stub_begin            () const          { return           header_begin() + _stub_offset          ; }
381   address stub_end              () const          { return           header_begin() + _oops_offset          ; }
382   address exception_begin       () const          { return           header_begin() + _exception_offset     ; }
383   address unwind_handler_begin  () const          { return _unwind_handler_offset != -1 ? (header_begin() + _unwind_handler_offset) : nullptr; }
384   oop*    oops_begin            () const          { return (oop*)   (header_begin() + _oops_offset)         ; }
385   oop*    oops_end              () const          { return (oop*)   (header_begin() + _metadata_offset)     ; }
386 
387   Metadata** metadata_begin   () const            { return (Metadata**)  (header_begin() + _metadata_offset)     ; }
388   Metadata** metadata_end     () const            { return (Metadata**)  _scopes_data_begin; }
389 
390   address scopes_data_end       () const          { return           header_begin() + _scopes_pcs_offset    ; }
391   PcDesc* scopes_pcs_begin      () const          { return (PcDesc*)(header_begin() + _scopes_pcs_offset   ); }
392   PcDesc* scopes_pcs_end        () const          { return (PcDesc*)(header_begin() + _dependencies_offset) ; }
393   address dependencies_begin    () const          { return           header_begin() + _dependencies_offset  ; }
394   address dependencies_end      () const          { return           header_begin() + _handler_table_offset ; }
395   address handler_table_begin   () const          { return           header_begin() + _handler_table_offset ; }
396   address handler_table_end     () const          { return           header_begin() + _nul_chk_table_offset ; }
397   address nul_chk_table_begin   () const          { return           header_begin() + _nul_chk_table_offset ; }
398 
399   int skipped_instructions_size () const          { return           _skipped_instructions_size             ; }
400 
401 #if INCLUDE_JVMCI
402   address nul_chk_table_end     () const          { return           header_begin() + _speculations_offset  ; }
403   address speculations_begin    () const          { return           header_begin() + _speculations_offset  ; }
404   address speculations_end      () const          { return           header_begin() + _jvmci_data_offset   ; }
405   address jvmci_data_begin      () const          { return           header_begin() + _jvmci_data_offset    ; }
406   address jvmci_data_end        () const          { return           header_begin() + _nmethod_end_offset   ; }
407 #else
408   address nul_chk_table_end     () const          { return           header_begin() + _nmethod_end_offset   ; }
409 #endif
410 
411   // Sizes
412   int oops_size         () const                  { return int((address)  oops_end         () - (address)  oops_begin         ()); }
413   int metadata_size     () const                  { return int((address)  metadata_end     () - (address)  metadata_begin     ()); }
414   int dependencies_size () const                  { return int(           dependencies_end () -            dependencies_begin ()); }
415 #if INCLUDE_JVMCI
416   int speculations_size () const                  { return int(           speculations_end () -            speculations_begin ()); }
417   int jvmci_data_size   () const                  { return int(           jvmci_data_end   () -            jvmci_data_begin   ()); }
418 #endif
419 
420   int     oops_count() const { assert(oops_size() % oopSize == 0, "");  return (oops_size() / oopSize) + 1; }
421   int metadata_count() const { assert(metadata_size() % wordSize == 0, ""); return (metadata_size() / wordSize) + 1; }
422 
423   int total_size        () const;
424 
425   // Containment
426   bool oops_contains         (oop*    addr) const { return oops_begin         () <= addr && addr < oops_end         (); }
427   bool metadata_contains     (Metadata** addr) const   { return metadata_begin     () <= addr && addr < metadata_end     (); }
428   bool scopes_data_contains  (address addr) const { return scopes_data_begin  () <= addr && addr < scopes_data_end  (); }
429   bool scopes_pcs_contains   (PcDesc* addr) const { return scopes_pcs_begin   () <= addr && addr < scopes_pcs_end   (); }
430 
431   // entry points
432   address entry_point() const                     { return _entry_point;             } // normal entry point
433   address verified_entry_point() const            { return _verified_entry_point;    } // if klass is correct
434 
435   // flag accessing and manipulation
436   bool  is_not_installed() const                  { return _state == not_installed; }
437   bool  is_in_use() const                         { return _state <= in_use; }
438   bool  is_not_entrant() const                    { return _state == not_entrant; }
439 
440   void clear_unloading_state();
441   // Heuristically deduce an nmethod isn't worth keeping around
442   bool is_cold();
443   virtual bool is_unloading();
444   virtual void do_unloading(bool unloading_occurred);
445 
446   bool is_unlinked() const                        { return _is_unlinked; }
447   void set_is_unlinked()                          { assert(!_is_unlinked, "already unlinked"); _is_unlinked = true; }
448 
449 #if INCLUDE_RTM_OPT
450   // rtm state accessing and manipulating
451   RTMState  rtm_state() const                     { return _rtm_state; }
452   void set_rtm_state(RTMState state)              { _rtm_state = state; }
453 #endif
454 
455   bool make_in_use() {
456     return try_transition(in_use);
457   }
458   // Make the nmethod non entrant. The nmethod will continue to be
459   // alive.  It is used when an uncommon trap happens.  Returns true
460   // if this thread changed the state of the nmethod or false if
461   // another thread performed the transition.
462   bool  make_not_entrant();
463   bool  make_not_used()    { return make_not_entrant(); }
464 
465   int get_state() const {
466     return _state;
467   }
468 
469   bool has_dependencies()                         { return dependencies_size() != 0; }
470   void print_dependencies_on(outputStream* out) PRODUCT_RETURN;
471   void flush_dependencies();
472   bool has_flushed_dependencies()                 { return _has_flushed_dependencies; }
473   void set_has_flushed_dependencies()             {
474     assert(!has_flushed_dependencies(), "should only happen once");
475     _has_flushed_dependencies = 1;
476   }
477 
478   int   comp_level() const                        { return _comp_level; }
479 
480   void unlink_from_method();
481 
482   // Support for oops in scopes and relocs:
483   // Note: index 0 is reserved for null.
484   oop   oop_at(int index) const;
485   oop   oop_at_phantom(int index) const; // phantom reference
486   oop*  oop_addr_at(int index) const {  // for GC
487     // relocation indexes are biased by 1 (because 0 is reserved)
488     assert(index > 0 && index <= oops_count(), "must be a valid non-zero index");
489     return &oops_begin()[index - 1];
490   }
491 
492   // Support for meta data in scopes and relocs:
493   // Note: index 0 is reserved for null.
494   Metadata*     metadata_at(int index) const      { return index == 0 ? nullptr: *metadata_addr_at(index); }
495   Metadata**  metadata_addr_at(int index) const {  // for GC
496     // relocation indexes are biased by 1 (because 0 is reserved)
497     assert(index > 0 && index <= metadata_count(), "must be a valid non-zero index");
498     return &metadata_begin()[index - 1];
499   }
500 
501   void copy_values(GrowableArray<jobject>* oops);
502   void copy_values(GrowableArray<Metadata*>* metadata);
503 
504   // Relocation support
505 private:
506   void fix_oop_relocations(address begin, address end, bool initialize_immediates);
507   inline void initialize_immediate_oop(oop* dest, jobject handle);
508 
509 public:
510   void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); }
511   void fix_oop_relocations()                           { fix_oop_relocations(nullptr, nullptr, false); }
512 
513   // On-stack replacement support
514   int   osr_entry_bci() const                     { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; }
515   address  osr_entry() const                      { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; }
516   void  invalidate_osr_method();
517   nmethod* osr_link() const                       { return _osr_link; }
518   void     set_osr_link(nmethod *n)               { _osr_link = n; }
519 
520   // Verify calls to dead methods have been cleaned.
521   void verify_clean_inline_caches();
522 
523   // Unlink this nmethod from the system
524   void unlink();
525 
526   // Deallocate this nmethod - called by the GC
527   void purge(bool free_code_cache_data, bool unregister_nmethod);
528 
529   // See comment at definition of _last_seen_on_stack
530   void mark_as_maybe_on_stack();
531   bool is_maybe_on_stack();
532 
533   // Evolution support. We make old (discarded) compiled methods point to new Method*s.
534   void set_method(Method* method) { _method = method; }
535 
536 #if INCLUDE_JVMCI
537   // Gets the JVMCI name of this nmethod.
538   const char* jvmci_name();
539 
540   // Records the pending failed speculation in the
541   // JVMCI speculation log associated with this nmethod.
542   void update_speculation(JavaThread* thread);
543 
544   // Gets the data specific to a JVMCI compiled method.
545   // This returns a non-nullptr value iff this nmethod was
546   // compiled by the JVMCI compiler.
547   JVMCINMethodData* jvmci_nmethod_data() const {
548     return jvmci_data_size() == 0 ? nullptr : (JVMCINMethodData*) jvmci_data_begin();
549   }
550 #endif
551 
552  public:
553   void oops_do(OopClosure* f) { oops_do(f, false); }
554   void oops_do(OopClosure* f, bool allow_dead);
555 
556   // All-in-one claiming of nmethods: returns true if the caller successfully claimed that
557   // nmethod.
558   bool oops_do_try_claim();
559 
560   // Loom support for following nmethods on the stack
561   void follow_nmethod(OopIterateClosure* cl);
562 
563   // Class containing callbacks for the oops_do_process_weak/strong() methods
564   // below.
565   class OopsDoProcessor {
566   public:
567     // Process the oops of the given nmethod based on whether it has been called
568     // in a weak or strong processing context, i.e. apply either weak or strong
569     // work on it.
570     virtual void do_regular_processing(nmethod* nm) = 0;
571     // Assuming that the oops of the given nmethod has already been its weak
572     // processing applied, apply the remaining strong processing part.
573     virtual void do_remaining_strong_processing(nmethod* nm) = 0;
574   };
575 
576   // The following two methods do the work corresponding to weak/strong nmethod
577   // processing.
578   void oops_do_process_weak(OopsDoProcessor* p);
579   void oops_do_process_strong(OopsDoProcessor* p);
580 
581   static void oops_do_marking_prologue();
582   static void oops_do_marking_epilogue();
583 
584  private:
585   ScopeDesc* scope_desc_in(address begin, address end);
586 
587   address* orig_pc_addr(const frame* fr);
588 
589   // used by jvmti to track if the load events has been reported
590   bool  load_reported() const                     { return _load_reported; }
591   void  set_load_reported()                       { _load_reported = true; }
592 
593  public:
594   // copying of debugging information
595   void copy_scopes_pcs(PcDesc* pcs, int count);
596   void copy_scopes_data(address buffer, int size);
597 
598   int orig_pc_offset() { return _orig_pc_offset; }
599 
600   // Post successful compilation
601   void post_compiled_method(CompileTask* task);
602 
603   // jvmti support:
604   void post_compiled_method_load_event(JvmtiThreadState* state = nullptr);
605 
606   // verify operations
607   void verify();
608   void verify_scopes();
609   void verify_interrupt_point(address interrupt_point, bool is_inline_cache);
610 
611   // Disassemble this nmethod with additional debug information, e.g. information about blocks.
612   void decode2(outputStream* st) const;
613   void print_constant_pool(outputStream* st);
614 
615   // Avoid hiding of parent's 'decode(outputStream*)' method.
616   void decode(outputStream* st) const { decode2(st); } // just delegate here.
617 
618   // printing support
619   void print()                          const;
620   void print(outputStream* st)          const;
621   void print_code();
622 
623 #if defined(SUPPORT_DATA_STRUCTS)
624   // print output in opt build for disassembler library
625   void print_relocations()                        PRODUCT_RETURN;
626   void print_pcs_on(outputStream* st);
627   void print_scopes() { print_scopes_on(tty); }
628   void print_scopes_on(outputStream* st)          PRODUCT_RETURN;
629   void print_value_on(outputStream* st) const;
630   void print_handler_table();
631   void print_nul_chk_table();
632   void print_recorded_oop(int log_n, int index);
633   void print_recorded_oops();
634   void print_recorded_metadata();
635 
636   void print_oops(outputStream* st);     // oops from the underlying CodeBlob.
637   void print_metadata(outputStream* st); // metadata in metadata pool.
638 #else
639   void print_pcs_on(outputStream* st) { return; }
640 #endif
641 
642   void print_calls(outputStream* st)              PRODUCT_RETURN;
643   static void print_statistics()                  PRODUCT_RETURN;
644 
645   void maybe_print_nmethod(const DirectiveSet* directive);
646   void print_nmethod(bool print_code);
647 
648   // need to re-define this from CodeBlob else the overload hides it
649   virtual void print_on(outputStream* st) const { CodeBlob::print_on(st); }
650   void print_on(outputStream* st, const char* msg) const;
651 
652   // Logging
653   void log_identity(xmlStream* log) const;
654   void log_new_nmethod() const;
655   void log_state_change() const;
656 
657   // Prints block-level comments, including nmethod specific block labels:
658   virtual void print_block_comment(outputStream* stream, address block_begin) const {
659 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
660     print_nmethod_labels(stream, block_begin);
661     CodeBlob::print_block_comment(stream, block_begin);
662 #endif
663   }
664 
665   void print_nmethod_labels(outputStream* stream, address block_begin, bool print_section_labels=true) const;
666   const char* nmethod_section_label(address pos) const;
667 
668   // returns whether this nmethod has code comments.
669   bool has_code_comment(address begin, address end);
670   // Prints a comment for one native instruction (reloc info, pc desc)
671   void print_code_comment_on(outputStream* st, int column, address begin, address end);
672 
673   // Compiler task identification.  Note that all OSR methods
674   // are numbered in an independent sequence if CICountOSR is true,
675   // and native method wrappers are also numbered independently if
676   // CICountNative is true.
677   virtual int compile_id() const { return _compile_id; }
678   const char* compile_kind() const;
679 
680   // tells if this compiled method is dependent on the given changes,
681   // and the changes have invalidated it
682   bool check_dependency_on(DepChange& changes);
683 
684   // Fast breakpoint support. Tells if this compiled method is
685   // dependent on the given method. Returns true if this nmethod
686   // corresponds to the given method as well.
687   virtual bool is_dependent_on_method(Method* dependee);
688 
689   // JVMTI's GetLocalInstance() support
690   ByteSize native_receiver_sp_offset() {
691     return _native_receiver_sp_offset;
692   }
693   ByteSize native_basic_lock_sp_offset() {
694     return _native_basic_lock_sp_offset;
695   }
696 
697   // support for code generation
698   static ByteSize verified_entry_point_offset() { return byte_offset_of(nmethod, _verified_entry_point); }
699   static ByteSize osr_entry_point_offset()      { return byte_offset_of(nmethod, _osr_entry_point); }
700   static ByteSize state_offset()                { return byte_offset_of(nmethod, _state); }
701 
702   virtual void metadata_do(MetadataClosure* f);
703 
704   address call_instruction_address(address pc) const;
705 
706   virtual void  make_deoptimized();
707   void finalize_relocations();
708 };
709 
710 #endif // SHARE_CODE_NMETHOD_HPP