1 /*
2 * Copyright (c) 1997, 2019, 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_CODE_NMETHOD_HPP
26 #define SHARE_CODE_NMETHOD_HPP
27
28 #include "code/compiledMethod.hpp"
29
30 class DepChange;
31 class DirectiveSet;
32 class DebugInformationRecorder;
33
34 // nmethods (native methods) are the compiled code versions of Java methods.
35 //
36 // An nmethod contains:
37 // - header (the nmethod structure)
38 // [Relocation]
39 // - relocation information
40 // - constant part (doubles, longs and floats used in nmethod)
41 // - oop table
42 // [Code]
43 // - code body
44 // - exception handler
45 // - stub code
46 // [Debugging information]
47 // - oop array
48 // - data array
49 // - pcs
50 // [Exception handler table]
51 // - handler entry point array
52 // [Implicit Null Pointer exception table]
53 // - implicit null table array
54
55 class nmethod : public CompiledMethod {
56 friend class VMStructs;
57 friend class JVMCIVMStructs;
58 friend class NMethodSweeper;
59 friend class CodeCache; // scavengable oops
60 private:
61
62 // Shared fields for all nmethod's
63 int _entry_bci; // != InvocationEntryBci if this nmethod is an on-stack replacement method
64 jmethodID _jmethod_id; // Cache of method()->jmethod_id()
65
66 #if INCLUDE_JVMCI
67 // A weak reference to an InstalledCode object associated with
68 // this nmethod.
69 jweak _jvmci_installed_code;
70
71 // A weak reference to a SpeculationLog object associated with
72 // this nmethod.
73 jweak _speculation_log;
74
75 // Determines whether this nmethod is unloaded when the
76 // referent in _jvmci_installed_code is cleared. This
77 // will be false if the referent is initialized to a
78 // HotSpotNMethod object whose isDefault field is true.
79 // That is, installed code other than a "default"
80 // HotSpotNMethod causes nmethod unloading.
81 // This field is ignored once _jvmci_installed_code is NULL.
82 bool _jvmci_installed_code_triggers_invalidation;
83 #endif
84
85 // To support simple linked-list chaining of nmethods:
86 nmethod* _osr_link; // from InstanceKlass::osr_nmethods_head
87
88 static nmethod* volatile _oops_do_mark_nmethods;
89 nmethod* volatile _oops_do_mark_link;
90
91 // offsets for entry points
92 address _entry_point; // entry point with class check
93 address _verified_entry_point; // entry point without class check
94 address _osr_entry_point; // entry point for on stack replacement
95
96 // Offsets for different nmethod parts
97 int _exception_offset;
98 // Offset of the unwind handler if it exists
99 int _unwind_handler_offset;
100
101 int _consts_offset;
102 int _stub_offset;
103 int _oops_offset; // offset to where embedded oop table begins (inside data)
104 int _metadata_offset; // embedded meta data table
105 int _scopes_data_offset;
106 int _scopes_pcs_offset;
107 int _dependencies_offset;
108 int _handler_table_offset;
109 int _nul_chk_table_offset;
110 int _nmethod_end_offset;
111
112 int code_offset() const { return (address) code_begin() - header_begin(); }
113
114 // location in frame (offset for sp) that deopt can store the original
115 // pc during a deopt.
116 int _orig_pc_offset;
117
118 int _compile_id; // which compilation made this nmethod
119 int _comp_level; // compilation level
120
121 // protected by CodeCache_lock
122 bool _has_flushed_dependencies; // Used for maintenance of dependencies (CodeCache_lock)
123
124 // used by jvmti to track if an unload event has been posted for this nmethod.
125 bool _unload_reported;
126
127 // Protected by Patching_lock
128 volatile signed char _state; // {not_installed, in_use, not_entrant, zombie, unloaded}
129
130 #ifdef ASSERT
131 bool _oops_are_stale; // indicates that it's no longer safe to access oops section
132 #endif
133
134 jbyte _scavenge_root_state;
135
136 #if INCLUDE_RTM_OPT
137 // RTM state at compile time. Used during deoptimization to decide
138 // whether to restart collecting RTM locking abort statistic again.
139 RTMState _rtm_state;
140 #endif
141
142 // Nmethod Flushing lock. If non-zero, then the nmethod is not removed
143 // and is not made into a zombie. However, once the nmethod is made into
144 // a zombie, it will be locked one final time if CompiledMethodUnload
145 // event processing needs to be done.
146 volatile jint _lock_count;
147
148 // not_entrant method removal. Each mark_sweep pass will update
149 // this mark to current sweep invocation count if it is seen on the
150 // stack. An not_entrant method can be removed when there are no
151 // more activations, i.e., when the _stack_traversal_mark is less than
152 // current sweep traversal index.
153 volatile long _stack_traversal_mark;
154
155 // The _hotness_counter indicates the hotness of a method. The higher
156 // the value the hotter the method. The hotness counter of a nmethod is
157 // set to [(ReservedCodeCacheSize / (1024 * 1024)) * 2] each time the method
158 // is active while stack scanning (mark_active_nmethods()). The hotness
159 // counter is decreased (by 1) while sweeping.
160 int _hotness_counter;
161
162 // Local state used to keep track of whether unloading is happening or not
163 volatile uint8_t _is_unloading_state;
164
165 // These are used for compiled synchronized native methods to
166 // locate the owner and stack slot for the BasicLock so that we can
167 // properly revoke the bias of the owner if necessary. They are
168 // needed because there is no debug information for compiled native
169 // wrappers and the oop maps are insufficient to allow
170 // frame::retrieve_receiver() to work. Currently they are expected
171 // to be byte offsets from the Java stack pointer for maximum code
172 // sharing between platforms. Note that currently biased locking
173 // will never cause Class instances to be biased but this code
174 // handles the static synchronized case as well.
175 // JVMTI's GetLocalInstance() also uses these offsets to find the receiver
176 // for non-static native wrapper frames.
177 ByteSize _native_receiver_sp_offset;
178 ByteSize _native_basic_lock_sp_offset;
179
180 friend class nmethodLocker;
181
182 // For native wrappers
183 nmethod(Method* method,
184 CompilerType type,
185 int nmethod_size,
186 int compile_id,
187 CodeOffsets* offsets,
188 CodeBuffer *code_buffer,
189 int frame_size,
190 ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */
191 ByteSize basic_lock_sp_offset, /* synchronized natives only */
192 OopMapSet* oop_maps);
193
194 // Creation support
195 nmethod(Method* method,
196 CompilerType type,
197 int nmethod_size,
198 int compile_id,
199 int entry_bci,
200 CodeOffsets* offsets,
201 int orig_pc_offset,
202 DebugInformationRecorder *recorder,
203 Dependencies* dependencies,
204 CodeBuffer *code_buffer,
205 int frame_size,
206 OopMapSet* oop_maps,
207 ExceptionHandlerTable* handler_table,
208 ImplicitExceptionTable* nul_chk_table,
209 AbstractCompiler* compiler,
210 int comp_level
211 #if INCLUDE_JVMCI
212 , jweak installed_code,
213 jweak speculation_log
214 #endif
215 );
216
217 // helper methods
218 void* operator new(size_t size, int nmethod_size, int comp_level) throw();
219
220 const char* reloc_string_for(u_char* begin, u_char* end);
221 // Returns true if this thread changed the state of the nmethod or
222 // false if another thread performed the transition.
223 bool make_not_entrant_or_zombie(int state);
224 bool make_entrant() { Unimplemented(); return false; }
225 void inc_decompile_count();
226
227 // Inform external interfaces that a compiled method has been unloaded
228 void post_compiled_method_unload();
229
230 // Initailize fields to their default values
231 void init_defaults();
232
233 // Offsets
234 int content_offset() const { return content_begin() - header_begin(); }
235 int data_offset() const { return _data_offset; }
236
237 address header_end() const { return (address) header_begin() + header_size(); }
238
239 public:
240 // create nmethod with entry_bci
241 static nmethod* new_nmethod(const methodHandle& method,
242 int compile_id,
243 int entry_bci,
244 CodeOffsets* offsets,
245 int orig_pc_offset,
246 DebugInformationRecorder* recorder,
247 Dependencies* dependencies,
248 CodeBuffer *code_buffer,
249 int frame_size,
250 OopMapSet* oop_maps,
251 ExceptionHandlerTable* handler_table,
252 ImplicitExceptionTable* nul_chk_table,
253 AbstractCompiler* compiler,
254 int comp_level
255 #if INCLUDE_JVMCI
256 , jweak installed_code = NULL,
257 jweak speculation_log = NULL
258 #endif
259 );
260
261 // Only used for unit tests.
262 nmethod()
263 : CompiledMethod(),
264 _is_unloading_state(0),
265 _native_receiver_sp_offset(in_ByteSize(-1)),
266 _native_basic_lock_sp_offset(in_ByteSize(-1)) {}
267
268
269 static nmethod* new_native_nmethod(const methodHandle& method,
270 int compile_id,
271 CodeBuffer *code_buffer,
272 int vep_offset,
273 int frame_complete,
274 int frame_size,
275 ByteSize receiver_sp_offset,
276 ByteSize basic_lock_sp_offset,
277 OopMapSet* oop_maps);
278
279 // type info
280 bool is_nmethod() const { return true; }
281 bool is_osr_method() const { return _entry_bci != InvocationEntryBci; }
282
283 // boundaries for different parts
284 address consts_begin () const { return header_begin() + _consts_offset ; }
285 address consts_end () const { return code_begin() ; }
286 address stub_begin () const { return header_begin() + _stub_offset ; }
287 address stub_end () const { return header_begin() + _oops_offset ; }
288 address exception_begin () const { return header_begin() + _exception_offset ; }
289 address unwind_handler_begin () const { return _unwind_handler_offset != -1 ? (header_begin() + _unwind_handler_offset) : NULL; }
290 oop* oops_begin () const { return (oop*) (header_begin() + _oops_offset) ; }
291 oop* oops_end () const { return (oop*) (header_begin() + _metadata_offset) ; }
292
293 Metadata** metadata_begin () const { return (Metadata**) (header_begin() + _metadata_offset) ; }
294 Metadata** metadata_end () const { return (Metadata**) _scopes_data_begin; }
295
296 address scopes_data_end () const { return header_begin() + _scopes_pcs_offset ; }
297 PcDesc* scopes_pcs_begin () const { return (PcDesc*)(header_begin() + _scopes_pcs_offset ); }
298 PcDesc* scopes_pcs_end () const { return (PcDesc*)(header_begin() + _dependencies_offset) ; }
299 address dependencies_begin () const { return header_begin() + _dependencies_offset ; }
300 address dependencies_end () const { return header_begin() + _handler_table_offset ; }
301 address handler_table_begin () const { return header_begin() + _handler_table_offset ; }
302 address handler_table_end () const { return header_begin() + _nul_chk_table_offset ; }
303 address nul_chk_table_begin () const { return header_begin() + _nul_chk_table_offset ; }
304 address nul_chk_table_end () const { return header_begin() + _nmethod_end_offset ; }
305
306 // Sizes
307 int oops_size () const { return (address) oops_end () - (address) oops_begin (); }
308 int metadata_size () const { return (address) metadata_end () - (address) metadata_begin (); }
309 int dependencies_size () const { return dependencies_end () - dependencies_begin (); }
310
311 int oops_count() const { assert(oops_size() % oopSize == 0, ""); return (oops_size() / oopSize) + 1; }
312 int metadata_count() const { assert(metadata_size() % wordSize == 0, ""); return (metadata_size() / wordSize) + 1; }
313
314 int total_size () const;
315
316 void dec_hotness_counter() { _hotness_counter--; }
317 void set_hotness_counter(int val) { _hotness_counter = val; }
318 int hotness_counter() const { return _hotness_counter; }
319
320 // Containment
321 bool oops_contains (oop* addr) const { return oops_begin () <= addr && addr < oops_end (); }
322 bool metadata_contains (Metadata** addr) const { return metadata_begin () <= addr && addr < metadata_end (); }
323 bool scopes_data_contains (address addr) const { return scopes_data_begin () <= addr && addr < scopes_data_end (); }
324 bool scopes_pcs_contains (PcDesc* addr) const { return scopes_pcs_begin () <= addr && addr < scopes_pcs_end (); }
325
326 // entry points
327 address entry_point() const { return _entry_point; } // normal entry point
328 address verified_entry_point() const { return _verified_entry_point; } // if klass is correct
329
330 // flag accessing and manipulation
331 bool is_not_installed() const { return _state == not_installed; }
332 bool is_in_use() const { return _state <= in_use; }
333 bool is_alive() const { return _state < zombie; }
334 bool is_not_entrant() const { return _state == not_entrant; }
335 bool is_zombie() const { return _state == zombie; }
336 bool is_unloaded() const { return _state == unloaded; }
337
338 void clear_unloading_state();
339 virtual bool is_unloading();
340 virtual void do_unloading(bool unloading_occurred);
341
342 #if INCLUDE_RTM_OPT
343 // rtm state accessing and manipulating
344 RTMState rtm_state() const { return _rtm_state; }
345 void set_rtm_state(RTMState state) { _rtm_state = state; }
346 #endif
347
348 void make_in_use() { _state = in_use; }
349 // Make the nmethod non entrant. The nmethod will continue to be
350 // alive. It is used when an uncommon trap happens. Returns true
351 // if this thread changed the state of the nmethod or false if
352 // another thread performed the transition.
353 bool make_not_entrant() {
354 assert(!method()->is_method_handle_intrinsic(), "Cannot make MH intrinsic not entrant");
355 return make_not_entrant_or_zombie(not_entrant);
356 }
357 bool make_not_used() { return make_not_entrant(); }
358 bool make_zombie() { return make_not_entrant_or_zombie(zombie); }
359
360 // used by jvmti to track if the unload event has been reported
361 bool unload_reported() { return _unload_reported; }
362 void set_unload_reported() { _unload_reported = true; }
363
364 int get_state() const {
365 return _state;
366 }
367
368 void make_unloaded();
369
370 bool has_dependencies() { return dependencies_size() != 0; }
371 void flush_dependencies(bool delete_immediately);
372 bool has_flushed_dependencies() { return _has_flushed_dependencies; }
373 void set_has_flushed_dependencies() {
374 assert(!has_flushed_dependencies(), "should only happen once");
375 _has_flushed_dependencies = 1;
376 }
377
378 int comp_level() const { return _comp_level; }
379
380 void unlink_from_method(bool acquire_lock);
381
382 // Support for oops in scopes and relocs:
383 // Note: index 0 is reserved for null.
384 oop oop_at(int index) const;
385 oop* oop_addr_at(int index) const { // for GC
386 // relocation indexes are biased by 1 (because 0 is reserved)
387 assert(index > 0 && index <= oops_count(), "must be a valid non-zero index");
388 assert(!_oops_are_stale, "oops are stale");
389 return &oops_begin()[index - 1];
390 }
391
392 // Support for meta data in scopes and relocs:
393 // Note: index 0 is reserved for null.
394 Metadata* metadata_at(int index) const { return index == 0 ? NULL: *metadata_addr_at(index); }
395 Metadata** metadata_addr_at(int index) const { // for GC
396 // relocation indexes are biased by 1 (because 0 is reserved)
397 assert(index > 0 && index <= metadata_count(), "must be a valid non-zero index");
398 return &metadata_begin()[index - 1];
399 }
400
401 void copy_values(GrowableArray<jobject>* oops);
402 void copy_values(GrowableArray<Metadata*>* metadata);
403
404 // Relocation support
405 private:
406 void fix_oop_relocations(address begin, address end, bool initialize_immediates);
407 inline void initialize_immediate_oop(oop* dest, jobject handle);
408
409 public:
410 void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); }
411 void fix_oop_relocations() { fix_oop_relocations(NULL, NULL, false); }
412
413 // Scavengable oop support
414 bool on_scavenge_root_list() const { return (_scavenge_root_state & 1) != 0; }
415 protected:
416 enum { sl_on_list = 0x01, sl_marked = 0x10 };
417 void set_on_scavenge_root_list() { _scavenge_root_state = sl_on_list; }
418 void clear_on_scavenge_root_list() { _scavenge_root_state = 0; }
419 // assertion-checking and pruning logic uses the bits of _scavenge_root_state
420 #ifndef PRODUCT
421 void set_scavenge_root_marked() { _scavenge_root_state |= sl_marked; }
422 void clear_scavenge_root_marked() { _scavenge_root_state &= ~sl_marked; }
423 bool scavenge_root_not_marked() { return (_scavenge_root_state &~ sl_on_list) == 0; }
424 // N.B. there is no positive marked query, and we only use the not_marked query for asserts.
425 #endif //PRODUCT
426 nmethod* scavenge_root_link() const { return _scavenge_root_link; }
427 void set_scavenge_root_link(nmethod *n) { _scavenge_root_link = n; }
428
429 public:
430
431 // Sweeper support
432 long stack_traversal_mark() { return _stack_traversal_mark; }
433 void set_stack_traversal_mark(long l) { _stack_traversal_mark = l; }
434
435 // implicit exceptions support
436 address continuation_for_implicit_exception(address pc);
437
438 // On-stack replacement support
439 int osr_entry_bci() const { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; }
440 address osr_entry() const { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; }
441 void invalidate_osr_method();
442 nmethod* osr_link() const { return _osr_link; }
443 void set_osr_link(nmethod *n) { _osr_link = n; }
444
445 // Verify calls to dead methods have been cleaned.
446 void verify_clean_inline_caches();
447
448 // unlink and deallocate this nmethod
449 // Only NMethodSweeper class is expected to use this. NMethodSweeper is not
450 // expected to use any other private methods/data in this class.
451
452 protected:
453 void flush();
454
455 public:
456 // When true is returned, it is unsafe to remove this nmethod even if
457 // it is a zombie, since the VM or the ServiceThread might still be
458 // using it.
459 bool is_locked_by_vm() const { return _lock_count >0; }
460
461 // See comment at definition of _last_seen_on_stack
462 void mark_as_seen_on_stack();
463 bool can_convert_to_zombie();
464
465 // Evolution support. We make old (discarded) compiled methods point to new Method*s.
466 void set_method(Method* method) { _method = method; }
467
468 #if INCLUDE_JVMCI
469 // Gets the InstalledCode 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 jvmci_installed_code();
473
474 // Copies the value of the name field in the InstalledCode
475 // object (if any) associated with this nmethod into buf.
476 // Returns the value of buf if it was updated otherwise NULL.
477 char* jvmci_installed_code_name(char* buf, size_t buflen) const;
478
479 // Updates the state of the InstalledCode (if any) associated with
480 // this nmethod based on the current value of _state.
481 void maybe_invalidate_installed_code();
482
483 // Deoptimizes the nmethod (if any) in the address field of a given
484 // InstalledCode object. The address field is zeroed upon return.
485 static void invalidate_installed_code(Handle installed_code, TRAPS);
486
487 // Gets the SpeculationLog object associated with this nmethod
488 // which may be NULL if this nmethod was not compiled by JVMCI
489 // or the weak reference has been cleared.
490 oop speculation_log();
491
492 private:
493 // Deletes the weak reference (if any) to the InstalledCode object
494 // associated with this nmethod.
495 void clear_jvmci_installed_code();
496
497 // Deletes the weak reference (if any) to the SpeculationLog object
498 // associated with this nmethod.
499 void clear_speculation_log();
500
501 public:
502 #endif
503
504 public:
505 void oops_do(OopClosure* f) { oops_do(f, false); }
506 void oops_do(OopClosure* f, bool allow_zombie);
507 bool detect_scavenge_root_oops();
508 void verify_scavenge_root_oops() PRODUCT_RETURN;
509
510 bool test_set_oops_do_mark();
511 static void oops_do_marking_prologue();
512 static void oops_do_marking_epilogue();
513 static bool oops_do_marking_is_active() { return _oops_do_mark_nmethods != NULL; }
514 bool test_oops_do_mark() { return _oops_do_mark_link != NULL; }
515
516 private:
517 ScopeDesc* scope_desc_in(address begin, address end);
518
519 address* orig_pc_addr(const frame* fr);
520
521 public:
522 // copying of debugging information
523 void copy_scopes_pcs(PcDesc* pcs, int count);
524 void copy_scopes_data(address buffer, int size);
525
526 // Accessor/mutator for the original pc of a frame before a frame was deopted.
527 address get_original_pc(const frame* fr) { return *orig_pc_addr(fr); }
528 void set_original_pc(const frame* fr, address pc) { *orig_pc_addr(fr) = pc; }
529
530 // jvmti support:
531 void post_compiled_method_load_event();
532 jmethodID get_and_cache_jmethod_id();
533
534 // verify operations
535 void verify();
536 void verify_scopes();
537 void verify_interrupt_point(address interrupt_point);
538
539 // printing support
540 void print() const;
541 void print_relocations() PRODUCT_RETURN;
542 void print_pcs() PRODUCT_RETURN;
543 void print_scopes() PRODUCT_RETURN;
544 void print_dependencies() PRODUCT_RETURN;
545 void print_value_on(outputStream* st) const PRODUCT_RETURN;
546 void print_calls(outputStream* st) PRODUCT_RETURN;
547 void print_handler_table() PRODUCT_RETURN;
548 void print_nul_chk_table() PRODUCT_RETURN;
549 void print_recorded_oops() PRODUCT_RETURN;
550 void print_recorded_metadata() PRODUCT_RETURN;
551
552 void maybe_print_nmethod(DirectiveSet* directive);
553 void print_nmethod(bool print_code);
554
555 // need to re-define this from CodeBlob else the overload hides it
556 virtual void print_on(outputStream* st) const { CodeBlob::print_on(st); }
557 void print_on(outputStream* st, const char* msg) const;
558
559 // Logging
560 void log_identity(xmlStream* log) const;
561 void log_new_nmethod() const;
562 void log_state_change() const;
563
564 // Prints block-level comments, including nmethod specific block labels:
565 virtual void print_block_comment(outputStream* stream, address block_begin) const {
566 print_nmethod_labels(stream, block_begin);
567 CodeBlob::print_block_comment(stream, block_begin);
568 }
569 void print_nmethod_labels(outputStream* stream, address block_begin) const;
570
571 // Prints a comment for one native instruction (reloc info, pc desc)
572 void print_code_comment_on(outputStream* st, int column, address begin, address end);
573 static void print_statistics() PRODUCT_RETURN;
574
575 // Compiler task identification. Note that all OSR methods
576 // are numbered in an independent sequence if CICountOSR is true,
577 // and native method wrappers are also numbered independently if
578 // CICountNative is true.
579 virtual int compile_id() const { return _compile_id; }
580 const char* compile_kind() const;
581
582 // tells if any of this method's dependencies have been invalidated
583 // (this is expensive!)
584 static void check_all_dependencies(DepChange& changes);
585
586 // tells if this compiled method is dependent on the given changes,
587 // and the changes have invalidated it
588 bool check_dependency_on(DepChange& changes);
589
590 // Evolution support. Tells if this compiled method is dependent on any of
591 // redefined methods, such that if m() is replaced,
592 // this compiled method will have to be deoptimized.
593 bool is_evol_dependent();
594
595 // Fast breakpoint support. Tells if this compiled method is
596 // dependent on the given method. Returns true if this nmethod
597 // corresponds to the given method as well.
598 virtual bool is_dependent_on_method(Method* dependee);
599
600 // is it ok to patch at address?
601 bool is_patchable_at(address instr_address);
602
603 // UseBiasedLocking support
604 ByteSize native_receiver_sp_offset() {
605 return _native_receiver_sp_offset;
606 }
607 ByteSize native_basic_lock_sp_offset() {
608 return _native_basic_lock_sp_offset;
609 }
610
611 // support for code generation
612 static int verified_entry_point_offset() { return offset_of(nmethod, _verified_entry_point); }
613 static int osr_entry_point_offset() { return offset_of(nmethod, _osr_entry_point); }
614 static int state_offset() { return offset_of(nmethod, _state); }
615
616 virtual void metadata_do(void f(Metadata*));
617
618 NativeCallWrapper* call_wrapper_at(address call) const;
619 NativeCallWrapper* call_wrapper_before(address return_pc) const;
620 address call_instruction_address(address pc) const;
621
622 virtual CompiledStaticCall* compiledStaticCall_at(Relocation* call_site) const;
623 virtual CompiledStaticCall* compiledStaticCall_at(address addr) const;
624 virtual CompiledStaticCall* compiledStaticCall_before(address addr) const;
625 };
626
627 // Locks an nmethod so its code will not get removed and it will not
628 // be made into a zombie, even if it is a not_entrant method. After the
629 // nmethod becomes a zombie, if CompiledMethodUnload event processing
630 // needs to be done, then lock_nmethod() is used directly to keep the
631 // generated code from being reused too early.
632 class nmethodLocker : public StackObj {
633 CompiledMethod* _nm;
634
635 public:
636
637 // note: nm can be NULL
638 // Only JvmtiDeferredEvent::compiled_method_unload_event()
639 // should pass zombie_ok == true.
640 static void lock_nmethod(CompiledMethod* nm, bool zombie_ok = false);
641 static void unlock_nmethod(CompiledMethod* nm); // (ditto)
642
643 nmethodLocker(address pc); // derive nm from pc
644 nmethodLocker(nmethod *nm) { _nm = nm; lock_nmethod(_nm); }
645 nmethodLocker(CompiledMethod *nm) {
646 _nm = nm;
647 lock(_nm);
648 }
649
650 static void lock(CompiledMethod* method) {
651 if (method == NULL) return;
652 lock_nmethod(method);
653 }
654
655 static void unlock(CompiledMethod* method) {
656 if (method == NULL) return;
657 unlock_nmethod(method);
658 }
659
660 nmethodLocker() { _nm = NULL; }
661 ~nmethodLocker() {
662 unlock(_nm);
663 }
664
665 CompiledMethod* code() { return _nm; }
666 void set_code(CompiledMethod* new_nm) {
667 unlock(_nm); // note: This works even if _nm==new_nm.
668 _nm = new_nm;
669 lock(_nm);
670 }
671 };
672
673 #endif // SHARE_CODE_NMETHOD_HPP