1 /*
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  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.
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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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 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
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 24 
 25 #ifndef SHARE_CODE_NMETHOD_HPP
 26 #define SHARE_CODE_NMETHOD_HPP
 27 
 28 #include "code/compiledMethod.hpp"
 29 #include "compiler/compilerDefinitions.hpp"
 30 
 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 == NULL: 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 NULL 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 _inline_entry_point;               // inline type entry point (unpack all inline type args) with class check
199   address _verified_inline_entry_point;      // inline type entry point (unpack all inline type args) without class check
200   address _verified_inline_ro_entry_point;   // inline type entry point (unpack receiver only) without class check
201   address _osr_entry_point;                  // entry point for on stack replacement
202 
203   nmethod* _unlinked_next;
204 
205   // Shared fields for all nmethod's
206   int _entry_bci;      // != InvocationEntryBci if this nmethod is an on-stack replacement method
207 
208   // Offsets for different nmethod parts
209   int  _exception_offset;
210   // Offset of the unwind handler if it exists
211   int _unwind_handler_offset;
212 
213   int _consts_offset;
214   int _stub_offset;
215   int _oops_offset;                       // offset to where embedded oop table begins (inside data)
216   int _metadata_offset;                   // embedded meta data table
217   int _scopes_data_offset;
218   int _scopes_pcs_offset;
219   int _dependencies_offset;
220   int _handler_table_offset;
221   int _nul_chk_table_offset;
222 #if INCLUDE_JVMCI
223   int _speculations_offset;
224   int _jvmci_data_offset;
225 #endif
226   int _nmethod_end_offset;
227 
228   int code_offset() const { return (address) code_begin() - header_begin(); }
229 
230   // location in frame (offset for sp) that deopt can store the original
231   // pc during a deopt.
232   int _orig_pc_offset;
233 
234   int _compile_id;                           // which compilation made this nmethod
235 
236 #if INCLUDE_RTM_OPT
237   // RTM state at compile time. Used during deoptimization to decide
238   // whether to restart collecting RTM locking abort statistic again.
239   RTMState _rtm_state;
240 #endif
241 
242   // These are used for compiled synchronized native methods to
243   // locate the owner and stack slot for the BasicLock. They are
244   // needed because there is no debug information for compiled native
245   // wrappers and the oop maps are insufficient to allow
246   // frame::retrieve_receiver() to work. Currently they are expected
247   // to be byte offsets from the Java stack pointer for maximum code
248   // sharing between platforms. JVMTI's GetLocalInstance() uses these
249   // offsets to find the receiver for non-static native wrapper frames.
250   ByteSize _native_receiver_sp_offset;
251   ByteSize _native_basic_lock_sp_offset;
252 
253   CompLevel _comp_level;               // compilation level
254 
255   // Local state used to keep track of whether unloading is happening or not
256   volatile uint8_t _is_unloading_state;
257 
258   // protected by CodeCache_lock
259   bool _has_flushed_dependencies;      // Used for maintenance of dependencies (CodeCache_lock)
260 
261   // used by jvmti to track if an event has been posted for this nmethod.
262   bool _load_reported;
263 
264   // Protected by CompiledMethod_lock
265   volatile signed char _state;         // {not_installed, in_use, not_used, not_entrant}
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,
298           int speculations_len,
299           int jvmci_data_size
300 #endif
301           );
302 
303   // helper methods
304   void* operator new(size_t size, int nmethod_size, int comp_level) throw();
305 
306   const char* reloc_string_for(u_char* begin, u_char* end);
307 
308   bool try_transition(int new_state);
309 
310   // Returns true if this thread changed the state of the nmethod or
311   // false if another thread performed the transition.
312   bool make_entrant() { Unimplemented(); return false; }
313   void inc_decompile_count();
314 
315   // Inform external interfaces that a compiled method has been unloaded
316   void post_compiled_method_unload();
317 
318   // Initialize fields to their default values
319   void init_defaults();
320 
321   // Offsets
322   int content_offset() const                  { return content_begin() - header_begin(); }
323   int data_offset() const                     { return _data_offset; }
324 
325   address header_end() const                  { return (address)    header_begin() + header_size(); }
326 
327  public:
328   // create nmethod with entry_bci
329   static nmethod* new_nmethod(const methodHandle& method,
330                               int compile_id,
331                               int entry_bci,
332                               CodeOffsets* offsets,
333                               int orig_pc_offset,
334                               DebugInformationRecorder* recorder,
335                               Dependencies* dependencies,
336                               CodeBuffer *code_buffer,
337                               int frame_size,
338                               OopMapSet* oop_maps,
339                               ExceptionHandlerTable* handler_table,
340                               ImplicitExceptionTable* nul_chk_table,
341                               AbstractCompiler* compiler,
342                               CompLevel comp_level
343 #if INCLUDE_JVMCI
344                               , char* speculations = NULL,
345                               int speculations_len = 0,
346                               int nmethod_mirror_index = -1,
347                               const char* nmethod_mirror_name = NULL,
348                               FailedSpeculation** failed_speculations = NULL
349 #endif
350   );
351 
352   // Only used for unit tests.
353   nmethod()
354     : CompiledMethod(),
355       _native_receiver_sp_offset(in_ByteSize(-1)),
356       _native_basic_lock_sp_offset(in_ByteSize(-1)),
357       _is_unloading_state(0) {}
358 
359 
360   static nmethod* new_native_nmethod(const methodHandle& method,
361                                      int compile_id,
362                                      CodeBuffer *code_buffer,
363                                      int vep_offset,
364                                      int frame_complete,
365                                      int frame_size,
366                                      ByteSize receiver_sp_offset,
367                                      ByteSize basic_lock_sp_offset,
368                                      OopMapSet* oop_maps,
369                                      int exception_handler = -1);
370 
371   // type info
372   bool is_nmethod() const                         { return true; }
373   bool is_osr_method() const                      { return _entry_bci != InvocationEntryBci; }
374 
375   // boundaries for different parts
376   address consts_begin          () const          { return           header_begin() + _consts_offset        ; }
377   address consts_end            () const          { return           code_begin()                           ; }
378   address stub_begin            () const          { return           header_begin() + _stub_offset          ; }
379   address stub_end              () const          { return           header_begin() + _oops_offset          ; }
380   address exception_begin       () const          { return           header_begin() + _exception_offset     ; }
381   address unwind_handler_begin  () const          { return _unwind_handler_offset != -1 ? (header_begin() + _unwind_handler_offset) : NULL; }
382   oop*    oops_begin            () const          { return (oop*)   (header_begin() + _oops_offset)         ; }
383   oop*    oops_end              () const          { return (oop*)   (header_begin() + _metadata_offset)     ; }
384 
385   Metadata** metadata_begin   () const            { return (Metadata**)  (header_begin() + _metadata_offset)     ; }
386   Metadata** metadata_end     () const            { return (Metadata**)  _scopes_data_begin; }
387 
388   address scopes_data_end       () const          { return           header_begin() + _scopes_pcs_offset    ; }
389   PcDesc* scopes_pcs_begin      () const          { return (PcDesc*)(header_begin() + _scopes_pcs_offset   ); }
390   PcDesc* scopes_pcs_end        () const          { return (PcDesc*)(header_begin() + _dependencies_offset) ; }
391   address dependencies_begin    () const          { return           header_begin() + _dependencies_offset  ; }
392   address dependencies_end      () const          { return           header_begin() + _handler_table_offset ; }
393   address handler_table_begin   () const          { return           header_begin() + _handler_table_offset ; }
394   address handler_table_end     () const          { return           header_begin() + _nul_chk_table_offset ; }
395   address nul_chk_table_begin   () const          { return           header_begin() + _nul_chk_table_offset ; }
396 #if INCLUDE_JVMCI
397   address nul_chk_table_end     () const          { return           header_begin() + _speculations_offset  ; }
398   address speculations_begin    () const          { return           header_begin() + _speculations_offset  ; }
399   address speculations_end      () const          { return           header_begin() + _jvmci_data_offset   ; }
400   address jvmci_data_begin      () const          { return           header_begin() + _jvmci_data_offset    ; }
401   address jvmci_data_end        () const          { return           header_begin() + _nmethod_end_offset   ; }
402 #else
403   address nul_chk_table_end     () const          { return           header_begin() + _nmethod_end_offset   ; }
404 #endif
405 
406   // Sizes
407   int oops_size         () const                  { return (address)  oops_end         () - (address)  oops_begin         (); }
408   int metadata_size     () const                  { return (address)  metadata_end     () - (address)  metadata_begin     (); }
409   int dependencies_size () const                  { return            dependencies_end () -            dependencies_begin (); }
410 #if INCLUDE_JVMCI
411   int speculations_size () const                  { return            speculations_end () -            speculations_begin (); }
412   int jvmci_data_size   () const                  { return            jvmci_data_end   () -            jvmci_data_begin   (); }
413 #endif
414 
415   int     oops_count() const { assert(oops_size() % oopSize == 0, "");  return (oops_size() / oopSize) + 1; }
416   int metadata_count() const { assert(metadata_size() % wordSize == 0, ""); return (metadata_size() / wordSize) + 1; }
417 
418   int total_size        () const;
419 
420   // Containment
421   bool oops_contains         (oop*    addr) const { return oops_begin         () <= addr && addr < oops_end         (); }
422   bool metadata_contains     (Metadata** addr) const   { return metadata_begin     () <= addr && addr < metadata_end     (); }
423   bool scopes_data_contains  (address addr) const { return scopes_data_begin  () <= addr && addr < scopes_data_end  (); }
424   bool scopes_pcs_contains   (PcDesc* addr) const { return scopes_pcs_begin   () <= addr && addr < scopes_pcs_end   (); }
425 
426   // entry points
427   address entry_point() const                     { return _entry_point;             }        // normal entry point
428   address verified_entry_point() const            { return _verified_entry_point;    }        // normal entry point without class check
429   address inline_entry_point() const              { return _inline_entry_point; }             // inline type entry point (unpack all inline type args)
430   address verified_inline_entry_point() const     { return _verified_inline_entry_point; }    // inline type entry point (unpack all inline type args) without class check
431   address verified_inline_ro_entry_point() const  { return _verified_inline_ro_entry_point; } // inline type entry point (only unpack receiver) without class check
432 
433   // flag accessing and manipulation
434   bool  is_not_installed() const                  { return _state == not_installed; }
435   bool  is_in_use() const                         { return _state <= in_use; }
436   bool  is_not_entrant() const                    { return _state == not_entrant; }
437 
438   void clear_unloading_state();
439   // Heuristically deduce an nmethod isn't worth keeping around
440   bool is_cold();
441   virtual bool is_unloading();
442   virtual void do_unloading(bool unloading_occurred);
443 
444   nmethod* unlinked_next() const                  { return _unlinked_next; }
445   void set_unlinked_next(nmethod* next)           { _unlinked_next = next; }
446 
447 #if INCLUDE_RTM_OPT
448   // rtm state accessing and manipulating
449   RTMState  rtm_state() const                     { return _rtm_state; }
450   void set_rtm_state(RTMState state)              { _rtm_state = state; }
451 #endif
452 
453   bool make_in_use() {
454     return try_transition(in_use);
455   }
456   // Make the nmethod non entrant. The nmethod will continue to be
457   // alive.  It is used when an uncommon trap happens.  Returns true
458   // if this thread changed the state of the nmethod or false if
459   // another thread performed the transition.
460   bool  make_not_entrant();
461   bool  make_not_used()    { return make_not_entrant(); }
462 
463   int get_state() const {
464     return _state;
465   }
466 
467   bool has_dependencies()                         { return dependencies_size() != 0; }
468   void print_dependencies()                       PRODUCT_RETURN;
469   void flush_dependencies();
470   bool has_flushed_dependencies()                 { return _has_flushed_dependencies; }
471   void set_has_flushed_dependencies()             {
472     assert(!has_flushed_dependencies(), "should only happen once");
473     _has_flushed_dependencies = 1;
474   }
475 
476   int   comp_level() const                        { return _comp_level; }
477 
478   void unlink_from_method();
479 
480   // Support for oops in scopes and relocs:
481   // Note: index 0 is reserved for null.
482   oop   oop_at(int index) const;
483   oop   oop_at_phantom(int index) const; // phantom reference
484   oop*  oop_addr_at(int index) const {  // for GC
485     // relocation indexes are biased by 1 (because 0 is reserved)
486     assert(index > 0 && index <= oops_count(), "must be a valid non-zero index");
487     return &oops_begin()[index - 1];
488   }
489 
490   // Support for meta data in scopes and relocs:
491   // Note: index 0 is reserved for null.
492   Metadata*     metadata_at(int index) const      { return index == 0 ? NULL: *metadata_addr_at(index); }
493   Metadata**  metadata_addr_at(int index) const {  // for GC
494     // relocation indexes are biased by 1 (because 0 is reserved)
495     assert(index > 0 && index <= metadata_count(), "must be a valid non-zero index");
496     return &metadata_begin()[index - 1];
497   }
498 
499   void copy_values(GrowableArray<jobject>* oops);
500   void copy_values(GrowableArray<Metadata*>* metadata);
501 
502   // Relocation support
503 private:
504   void fix_oop_relocations(address begin, address end, bool initialize_immediates);
505   inline void initialize_immediate_oop(oop* dest, jobject handle);
506 
507 public:
508   void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); }
509   void fix_oop_relocations()                           { fix_oop_relocations(NULL, NULL, false); }
510 
511   // On-stack replacement support
512   int   osr_entry_bci() const                     { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; }
513   address  osr_entry() const                      { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; }
514   void  invalidate_osr_method();
515   nmethod* osr_link() const                       { return _osr_link; }
516   void     set_osr_link(nmethod *n)               { _osr_link = n; }
517 
518   // Verify calls to dead methods have been cleaned.
519   void verify_clean_inline_caches();
520 
521   // Unlink this nmethod from the system
522   void unlink();
523 
524   // Deallocate this nmethod - called by the GC
525   void flush();
526 
527   // See comment at definition of _last_seen_on_stack
528   void mark_as_maybe_on_stack();
529   bool is_maybe_on_stack();
530 
531   // Evolution support. We make old (discarded) compiled methods point to new Method*s.
532   void set_method(Method* method) { _method = method; }
533 
534 #if INCLUDE_JVMCI
535   // Gets the JVMCI name of this nmethod.
536   const char* jvmci_name();
537 
538   // Records the pending failed speculation in the
539   // JVMCI speculation log associated with this nmethod.
540   void update_speculation(JavaThread* thread);
541 
542   // Gets the data specific to a JVMCI compiled method.
543   // This returns a non-NULL value iff this nmethod was
544   // compiled by the JVMCI compiler.
545   JVMCINMethodData* jvmci_nmethod_data() const {
546     return jvmci_data_size() == 0 ? NULL : (JVMCINMethodData*) jvmci_data_begin();
547   }
548 #endif
549 
550  public:
551   void oops_do(OopClosure* f) { oops_do(f, false); }
552   void oops_do(OopClosure* f, bool allow_dead);
553 
554   // All-in-one claiming of nmethods: returns true if the caller successfully claimed that
555   // nmethod.
556   bool oops_do_try_claim();
557 
558   // Loom support for following nmethods on the stack
559   void follow_nmethod(OopIterateClosure* cl);
560 
561   // Class containing callbacks for the oops_do_process_weak/strong() methods
562   // below.
563   class OopsDoProcessor {
564   public:
565     // Process the oops of the given nmethod based on whether it has been called
566     // in a weak or strong processing context, i.e. apply either weak or strong
567     // work on it.
568     virtual void do_regular_processing(nmethod* nm) = 0;
569     // Assuming that the oops of the given nmethod has already been its weak
570     // processing applied, apply the remaining strong processing part.
571     virtual void do_remaining_strong_processing(nmethod* nm) = 0;
572   };
573 
574   // The following two methods do the work corresponding to weak/strong nmethod
575   // processing.
576   void oops_do_process_weak(OopsDoProcessor* p);
577   void oops_do_process_strong(OopsDoProcessor* p);
578 
579   static void oops_do_marking_prologue();
580   static void oops_do_marking_epilogue();
581 
582  private:
583   ScopeDesc* scope_desc_in(address begin, address end);
584 
585   address* orig_pc_addr(const frame* fr);
586 
587   // used by jvmti to track if the load events has been reported
588   bool  load_reported() const                     { return _load_reported; }
589   void  set_load_reported()                       { _load_reported = true; }
590 
591  public:
592   // copying of debugging information
593   void copy_scopes_pcs(PcDesc* pcs, int count);
594   void copy_scopes_data(address buffer, int size);
595 
596   int orig_pc_offset() { return _orig_pc_offset; }
597 
598   // Post successful compilation
599   void post_compiled_method(CompileTask* task);
600 
601   // jvmti support:
602   void post_compiled_method_load_event(JvmtiThreadState* state = NULL);
603 
604   // verify operations
605   void verify();
606   void verify_scopes();
607   void verify_interrupt_point(address interrupt_point);
608 
609   // Disassemble this nmethod with additional debug information, e.g. information about blocks.
610   void decode2(outputStream* st) const;
611   void print_constant_pool(outputStream* st);
612 
613   // Avoid hiding of parent's 'decode(outputStream*)' method.
614   void decode(outputStream* st) const { decode2(st); } // just delegate here.
615 
616   // printing support
617   void print()                          const;
618   void print(outputStream* st)          const;
619   void print_code();
620 
621 #if defined(SUPPORT_DATA_STRUCTS)
622   // print output in opt build for disassembler library
623   void print_relocations()                        PRODUCT_RETURN;
624   void print_pcs() { print_pcs_on(tty); }
625   void print_pcs_on(outputStream* st);
626   void print_scopes() { print_scopes_on(tty); }
627   void print_scopes_on(outputStream* st)          PRODUCT_RETURN;
628   void print_value_on(outputStream* st) const;
629   void print_handler_table();
630   void print_nul_chk_table();
631   void print_recorded_oop(int log_n, int index);
632   void print_recorded_oops();
633   void print_recorded_metadata();
634 
635   void print_oops(outputStream* st);     // oops from the underlying CodeBlob.
636   void print_metadata(outputStream* st); // metadata in metadata pool.
637 #else
638   // void print_pcs()                             PRODUCT_RETURN;
639   void print_pcs()                                { 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 any of this method's dependencies have been invalidated
681   // (this is expensive!)
682   static void check_all_dependencies(DepChange& changes);
683 
684   // tells if this compiled method is dependent on the given changes,
685   // and the changes have invalidated it
686   bool check_dependency_on(DepChange& changes);
687 
688   // Fast breakpoint support. Tells if this compiled method is
689   // dependent on the given method. Returns true if this nmethod
690   // corresponds to the given method as well.
691   virtual bool is_dependent_on_method(Method* dependee);
692 
693   // JVMTI's GetLocalInstance() support
694   ByteSize native_receiver_sp_offset() {
695     return _native_receiver_sp_offset;
696   }
697   ByteSize native_basic_lock_sp_offset() {
698     return _native_basic_lock_sp_offset;
699   }
700 
701   // support for code generation
702   static int verified_entry_point_offset()        { return offset_of(nmethod, _verified_entry_point); }
703   static int osr_entry_point_offset()             { return offset_of(nmethod, _osr_entry_point); }
704   static int state_offset()                       { return offset_of(nmethod, _state); }
705 
706   virtual void metadata_do(MetadataClosure* f);
707 
708   NativeCallWrapper* call_wrapper_at(address call) const;
709   NativeCallWrapper* call_wrapper_before(address return_pc) const;
710   address call_instruction_address(address pc) const;
711 
712   virtual CompiledStaticCall* compiledStaticCall_at(Relocation* call_site) const;
713   virtual CompiledStaticCall* compiledStaticCall_at(address addr) const;
714   virtual CompiledStaticCall* compiledStaticCall_before(address addr) const;
715 
716   virtual void  make_deoptimized();
717   void finalize_relocations();
718 };
719 
720 #endif // SHARE_CODE_NMETHOD_HPP