1 /*
2 * Copyright (c) 1997, 2017, 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.
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23 */
24
25 #ifndef SHARE_VM_CODE_NMETHOD_HPP
26 #define SHARE_VM_CODE_NMETHOD_HPP
27
28 #include "code/compiledMethod.hpp"
29
30 class DepChange;
31 class DirectiveSet;
32
33 // nmethods (native methods) are the compiled code versions of Java methods.
34 //
35 // An nmethod contains:
36 // - header (the nmethod structure)
37 // [Relocation]
38 // - relocation information
39 // - constant part (doubles, longs and floats used in nmethod)
40 // - oop table
41 // [Code]
42 // - code body
43 // - exception handler
44 // - stub code
45 // [Debugging information]
46 // - oop array
47 // - data array
48 // - pcs
49 // [Exception handler table]
50 // - handler entry point array
51 // [Implicit Null Pointer exception table]
52 // - implicit null table array
53
54 class nmethod : public CompiledMethod {
55 friend class VMStructs;
56 friend class JVMCIVMStructs;
57 friend class NMethodSweeper;
58 friend class CodeCache; // scavengable oops
59 private:
60
61 // Shared fields for all nmethod's
62 int _entry_bci; // != InvocationEntryBci if this nmethod is an on-stack replacement method
63 jmethodID _jmethod_id; // Cache of method()->jmethod_id()
64
65 #if INCLUDE_JVMCI
66 // A weak reference to an InstalledCode object associated with
67 // this nmethod.
68 jweak _jvmci_installed_code;
69
70 // A weak reference to a SpeculationLog object associated with
71 // this nmethod.
72 jweak _speculation_log;
73
74 // Determines whether this nmethod is unloaded when the
75 // referent in _jvmci_installed_code is cleared. This
76 // will be false if the referent is initialized to a
77 // HotSpotNMethod object whose isDefault field is true.
78 // That is, installed code other than a "default"
79 // HotSpotNMethod causes nmethod unloading.
80 // This field is ignored once _jvmci_installed_code is NULL.
81 bool _jvmci_installed_code_triggers_unloading;
82 #endif
83
84 // To support simple linked-list chaining of nmethods:
85 nmethod* _osr_link; // from InstanceKlass::osr_nmethods_head
86
87 static nmethod* volatile _oops_do_mark_nmethods;
88 nmethod* volatile _oops_do_mark_link;
89
90 // offsets for entry points
91 address _entry_point; // entry point with class check
92 address _verified_entry_point; // entry point without class check
93 address _osr_entry_point; // entry point for on stack replacement
94
95 // Offsets for different nmethod parts
96 int _exception_offset;
97 // Offset of the unwind handler if it exists
98 int _unwind_handler_offset;
99
100 int _consts_offset;
101 int _stub_offset;
102 int _oops_offset; // offset to where embedded oop table begins (inside data)
103 int _metadata_offset; // embedded meta data table
104 int _scopes_data_offset;
105 int _scopes_pcs_offset;
106 int _dependencies_offset;
107 int _handler_table_offset;
108 int _nul_chk_table_offset;
109 int _nmethod_end_offset;
110
111 int code_offset() const { return (address) code_begin() - header_begin(); }
112
113 // location in frame (offset for sp) that deopt can store the original
114 // pc during a deopt.
115 int _orig_pc_offset;
116
117 int _compile_id; // which compilation made this nmethod
118 int _comp_level; // compilation level
119
120 // protected by CodeCache_lock
121 bool _has_flushed_dependencies; // Used for maintenance of dependencies (CodeCache_lock)
122
123 // used by jvmti to track if an unload event has been posted for this nmethod.
124 bool _unload_reported;
125
126 // Protected by Patching_lock
127 volatile signed char _state; // {not_installed, in_use, not_entrant, zombie, unloaded}
128
129 #ifdef ASSERT
130 bool _oops_are_stale; // indicates that it's no longer safe to access oops section
131 #endif
132
133 jbyte _scavenge_root_state;
134
135 #if INCLUDE_RTM_OPT
136 // RTM state at compile time. Used during deoptimization to decide
137 // whether to restart collecting RTM locking abort statistic again.
138 RTMState _rtm_state;
139 #endif
140
141 // Nmethod Flushing lock. If non-zero, then the nmethod is not removed
142 // and is not made into a zombie. However, once the nmethod is made into
143 // a zombie, it will be locked one final time if CompiledMethodUnload
144 // event processing needs to be done.
145 volatile jint _lock_count;
146
147 // not_entrant method removal. Each mark_sweep pass will update
148 // this mark to current sweep invocation count if it is seen on the
149 // stack. An not_entrant method can be removed when there are no
150 // more activations, i.e., when the _stack_traversal_mark is less than
151 // current sweep traversal index.
152 volatile long _stack_traversal_mark;
153
154 // The _hotness_counter indicates the hotness of a method. The higher
155 // the value the hotter the method. The hotness counter of a nmethod is
156 // set to [(ReservedCodeCacheSize / (1024 * 1024)) * 2] each time the method
157 // is active while stack scanning (mark_active_nmethods()). The hotness
158 // counter is decreased (by 1) while sweeping.
159 int _hotness_counter;
160
161 // These are used for compiled synchronized native methods to
162 // locate the owner and stack slot for the BasicLock so that we can
163 // properly revoke the bias of the owner if necessary. They are
164 // needed because there is no debug information for compiled native
165 // wrappers and the oop maps are insufficient to allow
166 // frame::retrieve_receiver() to work. Currently they are expected
167 // to be byte offsets from the Java stack pointer for maximum code
168 // sharing between platforms. Note that currently biased locking
169 // will never cause Class instances to be biased but this code
170 // handles the static synchronized case as well.
171 // JVMTI's GetLocalInstance() also uses these offsets to find the receiver
172 // for non-static native wrapper frames.
173 ByteSize _native_receiver_sp_offset;
174 ByteSize _native_basic_lock_sp_offset;
175
176 friend class nmethodLocker;
177
178 // For native wrappers
179 nmethod(Method* method,
180 CompilerType type,
181 int nmethod_size,
182 int compile_id,
183 CodeOffsets* offsets,
184 CodeBuffer *code_buffer,
185 int frame_size,
186 ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */
187 ByteSize basic_lock_sp_offset, /* synchronized natives only */
188 OopMapSet* oop_maps);
189
190 // Creation support
191 nmethod(Method* method,
192 CompilerType type,
193 int nmethod_size,
194 int compile_id,
195 int entry_bci,
196 CodeOffsets* offsets,
197 int orig_pc_offset,
198 DebugInformationRecorder *recorder,
199 Dependencies* dependencies,
200 CodeBuffer *code_buffer,
201 int frame_size,
202 OopMapSet* oop_maps,
203 ExceptionHandlerTable* handler_table,
204 ImplicitExceptionTable* nul_chk_table,
205 AbstractCompiler* compiler,
206 int comp_level
207 #if INCLUDE_JVMCI
208 , jweak installed_code,
209 jweak speculation_log
210 #endif
211 );
212
213 // helper methods
214 void* operator new(size_t size, int nmethod_size, int comp_level) throw();
215
216 const char* reloc_string_for(u_char* begin, u_char* end);
217 // Returns true if this thread changed the state of the nmethod or
218 // false if another thread performed the transition.
219 bool make_not_entrant_or_zombie(int state);
220 bool make_entrant() { Unimplemented(); return false; }
221 void inc_decompile_count();
222
223 // Inform external interfaces that a compiled method has been unloaded
224 void post_compiled_method_unload();
225
226 // Initailize fields to their default values
227 void init_defaults();
228
229 // Offsets
230 int content_offset() const { return content_begin() - header_begin(); }
231 int data_offset() const { return _data_offset; }
232
233 address header_end() const { return (address) header_begin() + header_size(); }
234
235 public:
236 // create nmethod with entry_bci
237 static nmethod* new_nmethod(const methodHandle& method,
238 int compile_id,
239 int entry_bci,
240 CodeOffsets* offsets,
241 int orig_pc_offset,
242 DebugInformationRecorder* recorder,
243 Dependencies* dependencies,
244 CodeBuffer *code_buffer,
245 int frame_size,
246 OopMapSet* oop_maps,
247 ExceptionHandlerTable* handler_table,
248 ImplicitExceptionTable* nul_chk_table,
249 AbstractCompiler* compiler,
250 int comp_level
251 #if INCLUDE_JVMCI
252 , jweak installed_code = NULL,
253 jweak speculation_log = NULL
254 #endif
255 );
256
257 static nmethod* new_native_nmethod(const methodHandle& method,
258 int compile_id,
259 CodeBuffer *code_buffer,
260 int vep_offset,
261 int frame_complete,
262 int frame_size,
263 ByteSize receiver_sp_offset,
264 ByteSize basic_lock_sp_offset,
265 OopMapSet* oop_maps);
266
267 // type info
268 bool is_nmethod() const { return true; }
269 bool is_osr_method() const { return _entry_bci != InvocationEntryBci; }
270
271 // boundaries for different parts
272 address consts_begin () const { return header_begin() + _consts_offset ; }
273 address consts_end () const { return code_begin() ; }
274 address stub_begin () const { return header_begin() + _stub_offset ; }
275 address stub_end () const { return header_begin() + _oops_offset ; }
276 address exception_begin () const { return header_begin() + _exception_offset ; }
277 address unwind_handler_begin () const { return _unwind_handler_offset != -1 ? (header_begin() + _unwind_handler_offset) : NULL; }
278 oop* oops_begin () const { return (oop*) (header_begin() + _oops_offset) ; }
279 oop* oops_end () const { return (oop*) (header_begin() + _metadata_offset) ; }
280
281 Metadata** metadata_begin () const { return (Metadata**) (header_begin() + _metadata_offset) ; }
282 Metadata** metadata_end () const { return (Metadata**) _scopes_data_begin; }
283
284 address scopes_data_end () const { return header_begin() + _scopes_pcs_offset ; }
285 PcDesc* scopes_pcs_begin () const { return (PcDesc*)(header_begin() + _scopes_pcs_offset ); }
286 PcDesc* scopes_pcs_end () const { return (PcDesc*)(header_begin() + _dependencies_offset) ; }
287 address dependencies_begin () const { return header_begin() + _dependencies_offset ; }
288 address dependencies_end () const { return header_begin() + _handler_table_offset ; }
289 address handler_table_begin () const { return header_begin() + _handler_table_offset ; }
290 address handler_table_end () const { return header_begin() + _nul_chk_table_offset ; }
291 address nul_chk_table_begin () const { return header_begin() + _nul_chk_table_offset ; }
292 address nul_chk_table_end () const { return header_begin() + _nmethod_end_offset ; }
293
294 // Sizes
295 int oops_size () const { return (address) oops_end () - (address) oops_begin (); }
296 int metadata_size () const { return (address) metadata_end () - (address) metadata_begin (); }
297 int dependencies_size () const { return dependencies_end () - dependencies_begin (); }
298
299 int oops_count() const { assert(oops_size() % oopSize == 0, ""); return (oops_size() / oopSize) + 1; }
300 int metadata_count() const { assert(metadata_size() % wordSize == 0, ""); return (metadata_size() / wordSize) + 1; }
301
302 int total_size () const;
303
304 void dec_hotness_counter() { _hotness_counter--; }
305 void set_hotness_counter(int val) { _hotness_counter = val; }
306 int hotness_counter() const { return _hotness_counter; }
307
308 // Containment
309 bool oops_contains (oop* addr) const { return oops_begin () <= addr && addr < oops_end (); }
310 bool metadata_contains (Metadata** addr) const { return metadata_begin () <= addr && addr < metadata_end (); }
311 bool scopes_data_contains (address addr) const { return scopes_data_begin () <= addr && addr < scopes_data_end (); }
312 bool scopes_pcs_contains (PcDesc* addr) const { return scopes_pcs_begin () <= addr && addr < scopes_pcs_end (); }
313
314 // entry points
315 address entry_point() const { return _entry_point; } // normal entry point
316 address verified_entry_point() const { return _verified_entry_point; } // if klass is correct
317
318 // flag accessing and manipulation
319 bool is_not_installed() const { return _state == not_installed; }
320 bool is_in_use() const { return _state <= in_use; }
321 bool is_alive() const { return _state < zombie; }
322 bool is_not_entrant() const { return _state == not_entrant; }
323 bool is_zombie() const { return _state == zombie; }
324 bool is_unloaded() const { return _state == unloaded; }
325
326 #if INCLUDE_RTM_OPT
327 // rtm state accessing and manipulating
328 RTMState rtm_state() const { return _rtm_state; }
329 void set_rtm_state(RTMState state) { _rtm_state = state; }
330 #endif
331
332 void make_in_use() { _state = in_use; }
333 // Make the nmethod non entrant. The nmethod will continue to be
334 // alive. It is used when an uncommon trap happens. Returns true
335 // if this thread changed the state of the nmethod or false if
336 // another thread performed the transition.
337 bool make_not_entrant() {
338 assert(!method()->is_method_handle_intrinsic(), "Cannot make MH intrinsic not entrant");
339 return make_not_entrant_or_zombie(not_entrant);
340 }
341 bool make_not_used() { return make_not_entrant(); }
342 bool make_zombie() { return make_not_entrant_or_zombie(zombie); }
343
344 // used by jvmti to track if the unload event has been reported
345 bool unload_reported() { return _unload_reported; }
346 void set_unload_reported() { _unload_reported = true; }
347
348 int get_state() const {
349 return _state;
350 }
351
352 void make_unloaded(BoolObjectClosure* is_alive, oop cause);
353
354 bool has_dependencies() { return dependencies_size() != 0; }
355 void flush_dependencies(BoolObjectClosure* is_alive);
356 bool has_flushed_dependencies() { return _has_flushed_dependencies; }
357 void set_has_flushed_dependencies() {
358 assert(!has_flushed_dependencies(), "should only happen once");
359 _has_flushed_dependencies = 1;
360 }
361
362 int comp_level() const { return _comp_level; }
363
364 // Support for oops in scopes and relocs:
365 // Note: index 0 is reserved for null.
366 oop oop_at(int index) const { return index == 0 ? (oop) NULL: *oop_addr_at(index); }
367 oop* oop_addr_at(int index) const { // for GC
368 // relocation indexes are biased by 1 (because 0 is reserved)
369 assert(index > 0 && index <= oops_count(), "must be a valid non-zero index");
370 assert(!_oops_are_stale, "oops are stale");
371 return &oops_begin()[index - 1];
372 }
373
374 // Support for meta data in scopes and relocs:
375 // Note: index 0 is reserved for null.
376 Metadata* metadata_at(int index) const { return index == 0 ? NULL: *metadata_addr_at(index); }
377 Metadata** metadata_addr_at(int index) const { // for GC
378 // relocation indexes are biased by 1 (because 0 is reserved)
379 assert(index > 0 && index <= metadata_count(), "must be a valid non-zero index");
380 return &metadata_begin()[index - 1];
381 }
382
383 void copy_values(GrowableArray<jobject>* oops);
384 void copy_values(GrowableArray<Metadata*>* metadata);
385
386 // Relocation support
387 private:
388 void fix_oop_relocations(address begin, address end, bool initialize_immediates);
389 inline void initialize_immediate_oop(oop* dest, jobject handle);
390
391 public:
392 void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); }
393 void fix_oop_relocations() { fix_oop_relocations(NULL, NULL, false); }
394
395 // Scavengable oop support
396 bool on_scavenge_root_list() const { return (_scavenge_root_state & 1) != 0; }
397 protected:
398 enum { sl_on_list = 0x01, sl_marked = 0x10 };
399 void set_on_scavenge_root_list() { _scavenge_root_state = sl_on_list; }
400 void clear_on_scavenge_root_list() { _scavenge_root_state = 0; }
401 // assertion-checking and pruning logic uses the bits of _scavenge_root_state
402 #ifndef PRODUCT
403 void set_scavenge_root_marked() { _scavenge_root_state |= sl_marked; }
404 void clear_scavenge_root_marked() { _scavenge_root_state &= ~sl_marked; }
405 bool scavenge_root_not_marked() { return (_scavenge_root_state &~ sl_on_list) == 0; }
406 // N.B. there is no positive marked query, and we only use the not_marked query for asserts.
407 #endif //PRODUCT
408 nmethod* scavenge_root_link() const { return _scavenge_root_link; }
409 void set_scavenge_root_link(nmethod *n) { _scavenge_root_link = n; }
410
411 public:
412
413 // Sweeper support
414 long stack_traversal_mark() { return _stack_traversal_mark; }
415 void set_stack_traversal_mark(long l) { _stack_traversal_mark = l; }
416
417 // implicit exceptions support
418 address continuation_for_implicit_exception(address pc);
419
420 // On-stack replacement support
421 int osr_entry_bci() const { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; }
422 address osr_entry() const { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; }
423 void invalidate_osr_method();
424 nmethod* osr_link() const { return _osr_link; }
425 void set_osr_link(nmethod *n) { _osr_link = n; }
426
427 // Verify calls to dead methods have been cleaned.
428 void verify_clean_inline_caches();
429
430 // unlink and deallocate this nmethod
431 // Only NMethodSweeper class is expected to use this. NMethodSweeper is not
432 // expected to use any other private methods/data in this class.
433
434 protected:
435 void flush();
436
437 public:
438 // When true is returned, it is unsafe to remove this nmethod even if
439 // it is a zombie, since the VM or the ServiceThread might still be
440 // using it.
441 bool is_locked_by_vm() const { return _lock_count >0; }
442
443 // See comment at definition of _last_seen_on_stack
444 void mark_as_seen_on_stack();
445 bool can_convert_to_zombie();
446
447 // Evolution support. We make old (discarded) compiled methods point to new Method*s.
448 void set_method(Method* method) { _method = method; }
449
450 #if INCLUDE_JVMCI
451 // Gets the InstalledCode object associated with this nmethod
452 // which may be NULL if this nmethod was not compiled by JVMCI
453 // or the weak reference has been cleared.
454 oop jvmci_installed_code();
455
456 // Copies the value of the name field in the InstalledCode
457 // object (if any) associated with this nmethod into buf.
458 // Returns the value of buf if it was updated otherwise NULL.
459 char* jvmci_installed_code_name(char* buf, size_t buflen);
460
461 // Updates the state of the InstalledCode (if any) associated with
462 // this nmethod based on the current value of _state.
463 void maybe_invalidate_installed_code();
464
465 // Deoptimizes the nmethod (if any) in the address field of a given
466 // InstalledCode object. The address field is zeroed upon return.
467 static void invalidate_installed_code(Handle installed_code, TRAPS);
468
469 // Gets the SpeculationLog object associated with this nmethod
470 // which may be NULL if this nmethod was not compiled by JVMCI
471 // or the weak reference has been cleared.
472 oop speculation_log();
473
474 private:
475 // Deletes the weak reference (if any) to the InstalledCode object
476 // associated with this nmethod.
477 void clear_jvmci_installed_code();
478
479 // Deletes the weak reference (if any) to the SpeculationLog object
480 // associated with this nmethod.
481 void clear_speculation_log();
482
483 public:
484 #endif
485
486 protected:
487 virtual bool do_unloading_oops(address low_boundary, BoolObjectClosure* is_alive, bool unloading_occurred);
488 #if INCLUDE_JVMCI
489 // See comment for _jvmci_installed_code_triggers_unloading field.
490 // Returns whether this nmethod was unloaded.
491 virtual bool do_unloading_jvmci(BoolObjectClosure* is_alive, bool unloading_occurred);
492 #endif
493
494 private:
495 bool do_unloading_scopes(BoolObjectClosure* is_alive, bool unloading_occurred);
496 // Unload a nmethod if the *root object is dead.
497 bool can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred);
498 bool unload_if_dead_at(RelocIterator *iter_at_oop, BoolObjectClosure* is_alive, bool unloading_occurred);
499
500 public:
501 void oops_do(OopClosure* f) { oops_do(f, false); }
502 void oops_do(OopClosure* f, bool allow_zombie);
503 bool detect_scavenge_root_oops();
504 void verify_scavenge_root_oops() PRODUCT_RETURN;
505
506 bool test_set_oops_do_mark();
507 static void oops_do_marking_prologue();
508 static void oops_do_marking_epilogue();
509 static bool oops_do_marking_is_active() { return _oops_do_mark_nmethods != NULL; }
510 bool test_oops_do_mark() { return _oops_do_mark_link != NULL; }
511
512 private:
513 ScopeDesc* scope_desc_in(address begin, address end);
514
515 address* orig_pc_addr(const frame* fr) { return (address*) ((address)fr->unextended_sp() + _orig_pc_offset); }
516
517 public:
518 // copying of debugging information
519 void copy_scopes_pcs(PcDesc* pcs, int count);
520 void copy_scopes_data(address buffer, int size);
521
522 // Accessor/mutator for the original pc of a frame before a frame was deopted.
523 address get_original_pc(const frame* fr) { return *orig_pc_addr(fr); }
524 void set_original_pc(const frame* fr, address pc) { *orig_pc_addr(fr) = pc; }
525
526 // jvmti support:
527 void post_compiled_method_load_event();
528 jmethodID get_and_cache_jmethod_id();
529
530 // verify operations
531 void verify();
532 void verify_scopes();
533 void verify_interrupt_point(address interrupt_point);
534
535 // printing support
536 void print() const;
537 void print_relocations() PRODUCT_RETURN;
538 void print_pcs() PRODUCT_RETURN;
539 void print_scopes() PRODUCT_RETURN;
540 void print_dependencies() PRODUCT_RETURN;
541 void print_value_on(outputStream* st) const PRODUCT_RETURN;
542 void print_calls(outputStream* st) PRODUCT_RETURN;
543 void print_handler_table() PRODUCT_RETURN;
544 void print_nul_chk_table() PRODUCT_RETURN;
545 void print_recorded_oops() PRODUCT_RETURN;
546 void print_recorded_metadata() PRODUCT_RETURN;
547
548 void maybe_print_nmethod(DirectiveSet* directive);
549 void print_nmethod(bool print_code);
550
551 // need to re-define this from CodeBlob else the overload hides it
552 virtual void print_on(outputStream* st) const { CodeBlob::print_on(st); }
553 void print_on(outputStream* st, const char* msg) const;
554
555 // Logging
556 void log_identity(xmlStream* log) const;
557 void log_new_nmethod() const;
558 void log_state_change() const;
559
560 // Prints block-level comments, including nmethod specific block labels:
561 virtual void print_block_comment(outputStream* stream, address block_begin) const {
562 print_nmethod_labels(stream, block_begin);
563 CodeBlob::print_block_comment(stream, block_begin);
564 }
565 void print_nmethod_labels(outputStream* stream, address block_begin) const;
566
567 // Prints a comment for one native instruction (reloc info, pc desc)
568 void print_code_comment_on(outputStream* st, int column, address begin, address end);
569 static void print_statistics() PRODUCT_RETURN;
570
571 // Compiler task identification. Note that all OSR methods
572 // are numbered in an independent sequence if CICountOSR is true,
573 // and native method wrappers are also numbered independently if
574 // CICountNative is true.
575 virtual int compile_id() const { return _compile_id; }
576 const char* compile_kind() const;
577
578 // tells if any of this method's dependencies have been invalidated
579 // (this is expensive!)
580 static void check_all_dependencies(DepChange& changes);
581
582 // tells if this compiled method is dependent on the given changes,
583 // and the changes have invalidated it
584 bool check_dependency_on(DepChange& changes);
585
586 // Evolution support. Tells if this compiled method is dependent on any of
587 // methods m() of class dependee, such that if m() in dependee is replaced,
588 // this compiled method will have to be deoptimized.
589 bool is_evol_dependent_on(Klass* dependee);
590
591 // Fast breakpoint support. Tells if this compiled method is
592 // dependent on the given method. Returns true if this nmethod
593 // corresponds to the given method as well.
594 virtual bool is_dependent_on_method(Method* dependee);
595
596 // is it ok to patch at address?
597 bool is_patchable_at(address instr_address);
598
599 // UseBiasedLocking support
600 ByteSize native_receiver_sp_offset() {
601 return _native_receiver_sp_offset;
602 }
603 ByteSize native_basic_lock_sp_offset() {
604 return _native_basic_lock_sp_offset;
605 }
606
607 // support for code generation
608 static int verified_entry_point_offset() { return offset_of(nmethod, _verified_entry_point); }
609 static int osr_entry_point_offset() { return offset_of(nmethod, _osr_entry_point); }
610 static int state_offset() { return offset_of(nmethod, _state); }
611
612 virtual void metadata_do(void f(Metadata*));
613
614 NativeCallWrapper* call_wrapper_at(address call) const;
615 NativeCallWrapper* call_wrapper_before(address return_pc) const;
616 address call_instruction_address(address pc) const;
617
618 virtual CompiledStaticCall* compiledStaticCall_at(Relocation* call_site) const;
619 virtual CompiledStaticCall* compiledStaticCall_at(address addr) const;
620 virtual CompiledStaticCall* compiledStaticCall_before(address addr) const;
621 };
622
623 // Locks an nmethod so its code will not get removed and it will not
624 // be made into a zombie, even if it is a not_entrant method. After the
625 // nmethod becomes a zombie, if CompiledMethodUnload event processing
626 // needs to be done, then lock_nmethod() is used directly to keep the
627 // generated code from being reused too early.
628 class nmethodLocker : public StackObj {
629 CompiledMethod* _nm;
630
631 public:
632
633 // note: nm can be NULL
634 // Only JvmtiDeferredEvent::compiled_method_unload_event()
635 // should pass zombie_ok == true.
636 static void lock_nmethod(CompiledMethod* nm, bool zombie_ok = false);
637 static void unlock_nmethod(CompiledMethod* nm); // (ditto)
638
639 nmethodLocker(address pc); // derive nm from pc
640 nmethodLocker(nmethod *nm) { _nm = nm; lock_nmethod(_nm); }
641 nmethodLocker(CompiledMethod *nm) {
642 _nm = nm;
643 lock(_nm);
644 }
645
646 static void lock(CompiledMethod* method) {
647 if (method == NULL) return;
648 lock_nmethod(method);
649 }
650
651 static void unlock(CompiledMethod* method) {
652 if (method == NULL) return;
653 unlock_nmethod(method);
654 }
655
656 nmethodLocker() { _nm = NULL; }
657 ~nmethodLocker() {
658 unlock(_nm);
659 }
660
661 CompiledMethod* code() { return _nm; }
662 void set_code(CompiledMethod* new_nm) {
663 unlock(_nm); // note: This works even if _nm==new_nm.
664 _nm = new_nm;
665 lock(_nm);
666 }
667 };
668
669 #endif // SHARE_VM_CODE_NMETHOD_HPP