1 /*
2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_CODE_NMETHOD_HPP
26 #define SHARE_VM_CODE_NMETHOD_HPP
27
28 #include "code/codeBlob.hpp"
29 #include "code/pcDesc.hpp"
30 #include "oops/metadata.hpp"
31
32 class DirectiveSet;
33
34 // This class is used internally by nmethods, to cache
35 // exception/pc/handler information.
36
37 class ExceptionCache : public CHeapObj<mtCode> {
38 friend class VMStructs;
39 private:
40 enum { cache_size = 16 };
41 Klass* _exception_type;
42 address _pc[cache_size];
43 address _handler[cache_size];
44 int _count;
45 ExceptionCache* _next;
46
47 address pc_at(int index) { assert(index >= 0 && index < count(),""); return _pc[index]; }
48 void set_pc_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _pc[index] = a; }
49 address handler_at(int index) { assert(index >= 0 && index < count(),""); return _handler[index]; }
50 void set_handler_at(int index, address a) { assert(index >= 0 && index < cache_size,""); _handler[index] = a; }
51 int count() { return _count; }
52 void increment_count() { _count++; }
53
54 public:
55
56 ExceptionCache(Handle exception, address pc, address handler);
57
58 Klass* exception_type() { return _exception_type; }
59 ExceptionCache* next() { return _next; }
60 void set_next(ExceptionCache *ec) { _next = ec; }
61
62 address match(Handle exception, address pc);
63 bool match_exception_with_space(Handle exception) ;
64 address test_address(address addr);
65 bool add_address_and_handler(address addr, address handler) ;
66 };
67
68
69 // cache pc descs found in earlier inquiries
70 class PcDescCache VALUE_OBJ_CLASS_SPEC {
71 friend class VMStructs;
72 private:
73 enum { cache_size = 4 };
74 // The array elements MUST be volatile! Several threads may modify
75 // and read from the cache concurrently. find_pc_desc_internal has
76 // returned wrong results. C++ compiler (namely xlC12) may duplicate
77 // C++ field accesses if the elements are not volatile.
78 typedef PcDesc* PcDescPtr;
79 volatile PcDescPtr _pc_descs[cache_size]; // last cache_size pc_descs found
80 public:
81 PcDescCache() { debug_only(_pc_descs[0] = NULL); }
82 void reset_to(PcDesc* initial_pc_desc);
83 PcDesc* find_pc_desc(int pc_offset, bool approximate);
84 void add_pc_desc(PcDesc* pc_desc);
85 PcDesc* last_pc_desc() { return _pc_descs[0]; }
86 };
87
88
89 // nmethods (native methods) are the compiled code versions of Java methods.
90 //
91 // An nmethod contains:
92 // - header (the nmethod structure)
93 // [Relocation]
94 // - relocation information
95 // - constant part (doubles, longs and floats used in nmethod)
96 // - oop table
97 // [Code]
98 // - code body
99 // - exception handler
100 // - stub code
101 // [Debugging information]
102 // - oop array
103 // - data array
104 // - pcs
105 // [Exception handler table]
106 // - handler entry point array
107 // [Implicit Null Pointer exception table]
108 // - implicit null table array
109
110 class DepChange;
111 class Dependencies;
112 class ExceptionHandlerTable;
113 class ImplicitExceptionTable;
114 class AbstractCompiler;
115 class xmlStream;
116
117 class nmethod : public CodeBlob {
118 friend class VMStructs;
119 friend class JVMCIVMStructs;
120 friend class NMethodSweeper;
121 friend class CodeCache; // scavengable oops
122 private:
123
124 // GC support to help figure out if an nmethod has been
125 // cleaned/unloaded by the current GC.
126 static unsigned char _global_unloading_clock;
127
128 // Shared fields for all nmethod's
129 Method* _method;
130 int _entry_bci; // != InvocationEntryBci if this nmethod is an on-stack replacement method
131 jmethodID _jmethod_id; // Cache of method()->jmethod_id()
132
133 #if INCLUDE_JVMCI
134 // Needed to keep nmethods alive that are not the default nmethod for the associated Method.
135 oop _jvmci_installed_code;
136 oop _speculation_log;
137 #endif
138
139 // To support simple linked-list chaining of nmethods:
140 nmethod* _osr_link; // from InstanceKlass::osr_nmethods_head
141
142 union {
143 // Used by G1 to chain nmethods.
144 nmethod* _unloading_next;
145 // Used by non-G1 GCs to chain nmethods.
146 nmethod* _scavenge_root_link; // from CodeCache::scavenge_root_nmethods
147 };
148
149 static nmethod* volatile _oops_do_mark_nmethods;
150 nmethod* volatile _oops_do_mark_link;
151
152 AbstractCompiler* _compiler; // The compiler which compiled this nmethod
153
154 // offsets for entry points
155 address _entry_point; // entry point with class check
156 address _verified_entry_point; // entry point without class check
157 address _osr_entry_point; // entry point for on stack replacement
158
159 // Offsets for different nmethod parts
160 int _exception_offset;
161 // All deoptee's will resume execution at this location described by
162 // this offset.
163 int _deoptimize_offset;
164 // All deoptee's at a MethodHandle call site will resume execution
165 // at this location described by this offset.
166 int _deoptimize_mh_offset;
167 // Offset of the unwind handler if it exists
168 int _unwind_handler_offset;
169
170 int _consts_offset;
171 int _stub_offset;
172 int _oops_offset; // offset to where embedded oop table begins (inside data)
173 int _metadata_offset; // embedded meta data table
174 int _scopes_data_offset;
175 int _scopes_pcs_offset;
176 int _dependencies_offset;
177 int _handler_table_offset;
178 int _nul_chk_table_offset;
179 int _nmethod_end_offset;
180
181 // location in frame (offset for sp) that deopt can store the original
182 // pc during a deopt.
183 int _orig_pc_offset;
184
185 int _compile_id; // which compilation made this nmethod
186 int _comp_level; // compilation level
187
188 // protected by CodeCache_lock
189 bool _has_flushed_dependencies; // Used for maintenance of dependencies (CodeCache_lock)
190
191 bool _marked_for_reclamation; // Used by NMethodSweeper (set only by sweeper)
192
193 enum MarkForDeoptimizationStatus {
194 not_marked,
195 deoptimize,
196 deoptimize_noupdate };
197
198 MarkForDeoptimizationStatus _mark_for_deoptimization_status; // Used for stack deoptimization
199
200 // used by jvmti to track if an unload event has been posted for this nmethod.
201 bool _unload_reported;
202
203 // set during construction
204 unsigned int _has_unsafe_access:1; // May fault due to unsafe access.
205 unsigned int _has_method_handle_invokes:1; // Has this method MethodHandle invokes?
206 unsigned int _lazy_critical_native:1; // Lazy JNI critical native
207 unsigned int _has_wide_vectors:1; // Preserve wide vectors at safepoints
208
209 // Protected by Patching_lock
210 volatile unsigned char _state; // {alive, not_entrant, zombie, unloaded}
211
212 volatile unsigned char _unloading_clock; // Incremented after GC unloaded/cleaned the nmethod
213
214 #ifdef ASSERT
215 bool _oops_are_stale; // indicates that it's no longer safe to access oops section
216 #endif
217
218 jbyte _scavenge_root_state;
219
220 #if INCLUDE_RTM_OPT
221 // RTM state at compile time. Used during deoptimization to decide
222 // whether to restart collecting RTM locking abort statistic again.
223 RTMState _rtm_state;
224 #endif
225
226 // Nmethod Flushing lock. If non-zero, then the nmethod is not removed
227 // and is not made into a zombie. However, once the nmethod is made into
228 // a zombie, it will be locked one final time if CompiledMethodUnload
229 // event processing needs to be done.
230 volatile jint _lock_count;
231
232 // not_entrant method removal. Each mark_sweep pass will update
233 // this mark to current sweep invocation count if it is seen on the
234 // stack. An not_entrant method can be removed when there are no
235 // more activations, i.e., when the _stack_traversal_mark is less than
236 // current sweep traversal index.
237 long _stack_traversal_mark;
238
239 // The _hotness_counter indicates the hotness of a method. The higher
240 // the value the hotter the method. The hotness counter of a nmethod is
241 // set to [(ReservedCodeCacheSize / (1024 * 1024)) * 2] each time the method
242 // is active while stack scanning (mark_active_nmethods()). The hotness
243 // counter is decreased (by 1) while sweeping.
244 int _hotness_counter;
245
246 ExceptionCache *_exception_cache;
247 PcDescCache _pc_desc_cache;
248
249 // These are used for compiled synchronized native methods to
250 // locate the owner and stack slot for the BasicLock so that we can
251 // properly revoke the bias of the owner if necessary. They are
252 // needed because there is no debug information for compiled native
253 // wrappers and the oop maps are insufficient to allow
254 // frame::retrieve_receiver() to work. Currently they are expected
255 // to be byte offsets from the Java stack pointer for maximum code
256 // sharing between platforms. Note that currently biased locking
257 // will never cause Class instances to be biased but this code
258 // handles the static synchronized case as well.
259 // JVMTI's GetLocalInstance() also uses these offsets to find the receiver
260 // for non-static native wrapper frames.
261 ByteSize _native_receiver_sp_offset;
262 ByteSize _native_basic_lock_sp_offset;
263
264 friend class nmethodLocker;
265
266 // For native wrappers
267 nmethod(Method* method,
268 int nmethod_size,
269 int compile_id,
270 CodeOffsets* offsets,
271 CodeBuffer *code_buffer,
272 int frame_size,
273 ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */
274 ByteSize basic_lock_sp_offset, /* synchronized natives only */
275 OopMapSet* oop_maps);
276
277 // Creation support
278 nmethod(Method* method,
279 int nmethod_size,
280 int compile_id,
281 int entry_bci,
282 CodeOffsets* offsets,
283 int orig_pc_offset,
284 DebugInformationRecorder *recorder,
285 Dependencies* dependencies,
286 CodeBuffer *code_buffer,
287 int frame_size,
288 OopMapSet* oop_maps,
289 ExceptionHandlerTable* handler_table,
290 ImplicitExceptionTable* nul_chk_table,
291 AbstractCompiler* compiler,
292 int comp_level
293 #if INCLUDE_JVMCI
294 , Handle installed_code,
295 Handle speculation_log
296 #endif
297 );
298
299 // helper methods
300 void* operator new(size_t size, int nmethod_size, int comp_level) throw();
301
302 const char* reloc_string_for(u_char* begin, u_char* end);
303 // Returns true if this thread changed the state of the nmethod or
304 // false if another thread performed the transition.
305 bool make_not_entrant_or_zombie(unsigned int state);
306 void inc_decompile_count();
307
308 // Used to manipulate the exception cache
309 void add_exception_cache_entry(ExceptionCache* new_entry);
310 ExceptionCache* exception_cache_entry_for_exception(Handle exception);
311
312 // Inform external interfaces that a compiled method has been unloaded
313 void post_compiled_method_unload();
314
315 // Initailize fields to their default values
316 void init_defaults();
317
318 public:
319 // create nmethod with entry_bci
320 static nmethod* new_nmethod(const methodHandle& method,
321 int compile_id,
322 int entry_bci,
323 CodeOffsets* offsets,
324 int orig_pc_offset,
325 DebugInformationRecorder* recorder,
326 Dependencies* dependencies,
327 CodeBuffer *code_buffer,
328 int frame_size,
329 OopMapSet* oop_maps,
330 ExceptionHandlerTable* handler_table,
331 ImplicitExceptionTable* nul_chk_table,
332 AbstractCompiler* compiler,
333 int comp_level
334 #if INCLUDE_JVMCI
335 , Handle installed_code = Handle(),
336 Handle speculation_log = Handle()
337 #endif
338 );
339
340 static nmethod* new_native_nmethod(const methodHandle& method,
341 int compile_id,
342 CodeBuffer *code_buffer,
343 int vep_offset,
344 int frame_complete,
345 int frame_size,
346 ByteSize receiver_sp_offset,
347 ByteSize basic_lock_sp_offset,
348 OopMapSet* oop_maps);
349
350 // accessors
351 Method* method() const { return _method; }
352 AbstractCompiler* compiler() const { return _compiler; }
353
354 // type info
355 bool is_nmethod() const { return true; }
356 bool is_java_method() const { return !method()->is_native(); }
357 bool is_native_method() const { return method()->is_native(); }
358 bool is_osr_method() const { return _entry_bci != InvocationEntryBci; }
359
360 bool is_compiled_by_c1() const;
361 bool is_compiled_by_jvmci() const;
362 bool is_compiled_by_c2() const;
363 bool is_compiled_by_shark() const;
364
365 // boundaries for different parts
366 address consts_begin () const { return header_begin() + _consts_offset ; }
367 address consts_end () const { return header_begin() + code_offset() ; }
368 address insts_begin () const { return header_begin() + code_offset() ; }
369 address insts_end () const { return header_begin() + _stub_offset ; }
370 address stub_begin () const { return header_begin() + _stub_offset ; }
371 address stub_end () const { return header_begin() + _oops_offset ; }
372 address exception_begin () const { return header_begin() + _exception_offset ; }
373 address deopt_handler_begin () const { return header_begin() + _deoptimize_offset ; }
374 address deopt_mh_handler_begin() const { return header_begin() + _deoptimize_mh_offset ; }
375 address unwind_handler_begin () const { return _unwind_handler_offset != -1 ? (header_begin() + _unwind_handler_offset) : NULL; }
376 oop* oops_begin () const { return (oop*) (header_begin() + _oops_offset) ; }
377 oop* oops_end () const { return (oop*) (header_begin() + _metadata_offset) ; }
378
379 Metadata** metadata_begin () const { return (Metadata**) (header_begin() + _metadata_offset) ; }
380 Metadata** metadata_end () const { return (Metadata**) (header_begin() + _scopes_data_offset) ; }
381
382 address scopes_data_begin () const { return header_begin() + _scopes_data_offset ; }
383 address scopes_data_end () const { return header_begin() + _scopes_pcs_offset ; }
384 PcDesc* scopes_pcs_begin () const { return (PcDesc*)(header_begin() + _scopes_pcs_offset ); }
385 PcDesc* scopes_pcs_end () const { return (PcDesc*)(header_begin() + _dependencies_offset) ; }
386 address dependencies_begin () const { return header_begin() + _dependencies_offset ; }
387 address dependencies_end () const { return header_begin() + _handler_table_offset ; }
388 address handler_table_begin () const { return header_begin() + _handler_table_offset ; }
389 address handler_table_end () const { return header_begin() + _nul_chk_table_offset ; }
390 address nul_chk_table_begin () const { return header_begin() + _nul_chk_table_offset ; }
391 address nul_chk_table_end () const { return header_begin() + _nmethod_end_offset ; }
392
393 // Sizes
394 int consts_size () const { return consts_end () - consts_begin (); }
395 int insts_size () const { return insts_end () - insts_begin (); }
396 int stub_size () const { return stub_end () - stub_begin (); }
397 int oops_size () const { return (address) oops_end () - (address) oops_begin (); }
398 int metadata_size () const { return (address) metadata_end () - (address) metadata_begin (); }
399 int scopes_data_size () const { return scopes_data_end () - scopes_data_begin (); }
400 int scopes_pcs_size () const { return (intptr_t) scopes_pcs_end () - (intptr_t) scopes_pcs_begin (); }
401 int dependencies_size () const { return dependencies_end () - dependencies_begin (); }
402 int handler_table_size() const { return handler_table_end() - handler_table_begin(); }
403 int nul_chk_table_size() const { return nul_chk_table_end() - nul_chk_table_begin(); }
404
405 int oops_count() const { assert(oops_size() % oopSize == 0, ""); return (oops_size() / oopSize) + 1; }
406 int metadata_count() const { assert(metadata_size() % wordSize == 0, ""); return (metadata_size() / wordSize) + 1; }
407
408 int total_size () const;
409
410 void dec_hotness_counter() { _hotness_counter--; }
411 void set_hotness_counter(int val) { _hotness_counter = val; }
412 int hotness_counter() const { return _hotness_counter; }
413
414 // Containment
415 bool consts_contains (address addr) const { return consts_begin () <= addr && addr < consts_end (); }
416 bool insts_contains (address addr) const { return insts_begin () <= addr && addr < insts_end (); }
417 bool stub_contains (address addr) const { return stub_begin () <= addr && addr < stub_end (); }
418 bool oops_contains (oop* addr) const { return oops_begin () <= addr && addr < oops_end (); }
419 bool metadata_contains (Metadata** addr) const { return metadata_begin () <= addr && addr < metadata_end (); }
420 bool scopes_data_contains (address addr) const { return scopes_data_begin () <= addr && addr < scopes_data_end (); }
421 bool scopes_pcs_contains (PcDesc* addr) const { return scopes_pcs_begin () <= addr && addr < scopes_pcs_end (); }
422 bool handler_table_contains(address addr) const { return handler_table_begin() <= addr && addr < handler_table_end(); }
423 bool nul_chk_table_contains(address addr) const { return nul_chk_table_begin() <= addr && addr < nul_chk_table_end(); }
424
425 // entry points
426 address entry_point() const { return _entry_point; } // normal entry point
427 address verified_entry_point() const { return _verified_entry_point; } // if klass is correct
428
429 enum { in_use = 0, // executable nmethod
430 not_entrant = 1, // marked for deoptimization but activations may still exist,
431 // will be transformed to zombie when all activations are gone
432 zombie = 2, // no activations exist, nmethod is ready for purge
433 unloaded = 3 }; // there should be no activations, should not be called,
434 // will be transformed to zombie immediately
435
436 // flag accessing and manipulation
437 bool is_in_use() const { return _state == in_use; }
438 bool is_alive() const { return _state == in_use || _state == not_entrant; }
439 bool is_not_entrant() const { return _state == not_entrant; }
440 bool is_zombie() const { return _state == zombie; }
441 bool is_unloaded() const { return _state == unloaded; }
442
443 #if INCLUDE_RTM_OPT
444 // rtm state accessing and manipulating
445 RTMState rtm_state() const { return _rtm_state; }
446 void set_rtm_state(RTMState state) { _rtm_state = state; }
447 #endif
448
449 // Make the nmethod non entrant. The nmethod will continue to be
450 // alive. It is used when an uncommon trap happens. Returns true
451 // if this thread changed the state of the nmethod or false if
452 // another thread performed the transition.
453 bool make_not_entrant() {
454 assert(!method()->is_method_handle_intrinsic(), "Cannot make MH intrinsic not entrant");
455 return make_not_entrant_or_zombie(not_entrant);
456 }
457 bool make_zombie() { return make_not_entrant_or_zombie(zombie); }
458
459 // used by jvmti to track if the unload event has been reported
460 bool unload_reported() { return _unload_reported; }
461 void set_unload_reported() { _unload_reported = true; }
462
463 void set_unloading_next(nmethod* next) { _unloading_next = next; }
464 nmethod* unloading_next() { return _unloading_next; }
465
466 static unsigned char global_unloading_clock() { return _global_unloading_clock; }
467 static void increase_unloading_clock();
468
469 void set_unloading_clock(unsigned char unloading_clock);
470 unsigned char unloading_clock();
471
472 bool is_marked_for_deoptimization() const { return _mark_for_deoptimization_status != not_marked; }
473 void mark_for_deoptimization(bool inc_recompile_counts = true) {
474 _mark_for_deoptimization_status = (inc_recompile_counts ? deoptimize : deoptimize_noupdate);
475 }
476 bool update_recompile_counts() const {
477 // Update recompile counts when either the update is explicitly requested (deoptimize)
478 // or the nmethod is not marked for deoptimization at all (not_marked).
479 // The latter happens during uncommon traps when deoptimized nmethod is made not entrant.
480 return _mark_for_deoptimization_status != deoptimize_noupdate;
481 }
482
483 void make_unloaded(BoolObjectClosure* is_alive, oop cause);
484
485 bool has_dependencies() { return dependencies_size() != 0; }
486 void flush_dependencies(BoolObjectClosure* is_alive);
487 bool has_flushed_dependencies() { return _has_flushed_dependencies; }
488 void set_has_flushed_dependencies() {
489 assert(!has_flushed_dependencies(), "should only happen once");
490 _has_flushed_dependencies = 1;
491 }
492
493 bool is_marked_for_reclamation() const { return _marked_for_reclamation; }
494 void mark_for_reclamation() { _marked_for_reclamation = 1; }
495
496 bool has_unsafe_access() const { return _has_unsafe_access; }
497 void set_has_unsafe_access(bool z) { _has_unsafe_access = z; }
498
499 bool has_method_handle_invokes() const { return _has_method_handle_invokes; }
500 void set_has_method_handle_invokes(bool z) { _has_method_handle_invokes = z; }
501
502 bool is_lazy_critical_native() const { return _lazy_critical_native; }
503 void set_lazy_critical_native(bool z) { _lazy_critical_native = z; }
504
505 bool has_wide_vectors() const { return _has_wide_vectors; }
506 void set_has_wide_vectors(bool z) { _has_wide_vectors = z; }
507
508 int comp_level() const { return _comp_level; }
509
510 // Support for oops in scopes and relocs:
511 // Note: index 0 is reserved for null.
512 oop oop_at(int index) const { return index == 0 ? (oop) NULL: *oop_addr_at(index); }
513 oop* oop_addr_at(int index) const { // for GC
514 // relocation indexes are biased by 1 (because 0 is reserved)
515 assert(index > 0 && index <= oops_count(), "must be a valid non-zero index");
516 assert(!_oops_are_stale, "oops are stale");
517 return &oops_begin()[index - 1];
518 }
519
520 // Support for meta data in scopes and relocs:
521 // Note: index 0 is reserved for null.
522 Metadata* metadata_at(int index) const { return index == 0 ? NULL: *metadata_addr_at(index); }
523 Metadata** metadata_addr_at(int index) const { // for GC
524 // relocation indexes are biased by 1 (because 0 is reserved)
525 assert(index > 0 && index <= metadata_count(), "must be a valid non-zero index");
526 return &metadata_begin()[index - 1];
527 }
528
529 void copy_values(GrowableArray<jobject>* oops);
530 void copy_values(GrowableArray<Metadata*>* metadata);
531
532 Method* attached_method(address call_pc);
533 Method* attached_method_before_pc(address pc);
534
535 // Relocation support
536 private:
537 void fix_oop_relocations(address begin, address end, bool initialize_immediates);
538 inline void initialize_immediate_oop(oop* dest, jobject handle);
539
540 public:
541 void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); }
542 void fix_oop_relocations() { fix_oop_relocations(NULL, NULL, false); }
543 void verify_oop_relocations();
544
545 bool is_at_poll_return(address pc);
546 bool is_at_poll_or_poll_return(address pc);
547
548 // Scavengable oop support
549 bool on_scavenge_root_list() const { return (_scavenge_root_state & 1) != 0; }
550 protected:
551 enum { sl_on_list = 0x01, sl_marked = 0x10 };
552 void set_on_scavenge_root_list() { _scavenge_root_state = sl_on_list; }
553 void clear_on_scavenge_root_list() { _scavenge_root_state = 0; }
554 // assertion-checking and pruning logic uses the bits of _scavenge_root_state
555 #ifndef PRODUCT
556 void set_scavenge_root_marked() { _scavenge_root_state |= sl_marked; }
557 void clear_scavenge_root_marked() { _scavenge_root_state &= ~sl_marked; }
558 bool scavenge_root_not_marked() { return (_scavenge_root_state &~ sl_on_list) == 0; }
559 // N.B. there is no positive marked query, and we only use the not_marked query for asserts.
560 #endif //PRODUCT
561 nmethod* scavenge_root_link() const { return _scavenge_root_link; }
562 void set_scavenge_root_link(nmethod *n) { _scavenge_root_link = n; }
563
564 public:
565
566 // Sweeper support
567 long stack_traversal_mark() { return _stack_traversal_mark; }
568 void set_stack_traversal_mark(long l) { _stack_traversal_mark = l; }
569
570 // Exception cache support
571 ExceptionCache* exception_cache() const { return _exception_cache; }
572 void set_exception_cache(ExceptionCache *ec) { _exception_cache = ec; }
573 address handler_for_exception_and_pc(Handle exception, address pc);
574 void add_handler_for_exception_and_pc(Handle exception, address pc, address handler);
575 void clean_exception_cache(BoolObjectClosure* is_alive);
576
577 // implicit exceptions support
578 address continuation_for_implicit_exception(address pc);
579
580 // On-stack replacement support
581 int osr_entry_bci() const { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; }
582 address osr_entry() const { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; }
583 void invalidate_osr_method();
584 nmethod* osr_link() const { return _osr_link; }
585 void set_osr_link(nmethod *n) { _osr_link = n; }
586
587 // tells whether frames described by this nmethod can be deoptimized
588 // note: native wrappers cannot be deoptimized.
589 bool can_be_deoptimized() const { return is_java_method(); }
590
591 // Inline cache support
592 void clear_inline_caches();
593 void clear_ic_stubs();
594 void cleanup_inline_caches();
595 bool inlinecache_check_contains(address addr) const {
596 return (addr >= code_begin() && addr < verified_entry_point());
597 }
598
599 // Verify calls to dead methods have been cleaned.
600 void verify_clean_inline_caches();
601 // Verify and count cached icholder relocations.
602 int verify_icholder_relocations();
603 // Check that all metadata is still alive
604 void verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive);
605
606 // unlink and deallocate this nmethod
607 // Only NMethodSweeper class is expected to use this. NMethodSweeper is not
608 // expected to use any other private methods/data in this class.
609
610 protected:
611 void flush();
612
613 public:
614 // When true is returned, it is unsafe to remove this nmethod even if
615 // it is a zombie, since the VM or the ServiceThread might still be
616 // using it.
617 bool is_locked_by_vm() const { return _lock_count >0; }
618
619 // See comment at definition of _last_seen_on_stack
620 void mark_as_seen_on_stack();
621 bool can_convert_to_zombie();
622
623 // Evolution support. We make old (discarded) compiled methods point to new Method*s.
624 void set_method(Method* method) { _method = method; }
625
626 #if INCLUDE_JVMCI
627 oop jvmci_installed_code() { return _jvmci_installed_code ; }
628 char* jvmci_installed_code_name(char* buf, size_t buflen);
629
630 // Update the state of any InstalledCode instance associated with
631 // this nmethod based on the current value of _state.
632 void maybe_invalidate_installed_code();
633
634 // Helper function to invalidate InstalledCode instances
635 static void invalidate_installed_code(Handle installed_code, TRAPS);
636
637 oop speculation_log() { return _speculation_log ; }
638
639 private:
640 void clear_jvmci_installed_code();
641
642 public:
643 #endif
644
645 // GC support
646 void do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred);
647 // The parallel versions are used by G1.
648 bool do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred);
649 void do_unloading_parallel_postponed(BoolObjectClosure* is_alive, bool unloading_occurred);
650
651 private:
652 // Unload a nmethod if the *root object is dead.
653 bool can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred);
654 bool unload_if_dead_at(RelocIterator *iter_at_oop, BoolObjectClosure* is_alive, bool unloading_occurred);
655
656 public:
657 void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map,
658 OopClosure* f);
659 void oops_do(OopClosure* f) { oops_do(f, false); }
660 void oops_do(OopClosure* f, bool allow_zombie);
661 bool detect_scavenge_root_oops();
662 void verify_scavenge_root_oops() PRODUCT_RETURN;
663
664 bool test_set_oops_do_mark();
665 static void oops_do_marking_prologue();
666 static void oops_do_marking_epilogue();
667 static bool oops_do_marking_is_active() { return _oops_do_mark_nmethods != NULL; }
668 bool test_oops_do_mark() { return _oops_do_mark_link != NULL; }
669
670 // ScopeDesc for an instruction
671 ScopeDesc* scope_desc_at(address pc);
672
673 private:
674 ScopeDesc* scope_desc_in(address begin, address end);
675
676 address* orig_pc_addr(const frame* fr) { return (address*) ((address)fr->unextended_sp() + _orig_pc_offset); }
677
678 PcDesc* find_pc_desc_internal(address pc, bool approximate);
679
680 PcDesc* find_pc_desc(address pc, bool approximate) {
681 PcDesc* desc = _pc_desc_cache.last_pc_desc();
682 if (desc != NULL && desc->pc_offset() == pc - code_begin()) {
683 return desc;
684 }
685 return find_pc_desc_internal(pc, approximate);
686 }
687
688 public:
689 // ScopeDesc retrieval operation
690 PcDesc* pc_desc_at(address pc) { return find_pc_desc(pc, false); }
691 // pc_desc_near returns the first PcDesc at or after the givne pc.
692 PcDesc* pc_desc_near(address pc) { return find_pc_desc(pc, true); }
693
694 public:
695 // copying of debugging information
696 void copy_scopes_pcs(PcDesc* pcs, int count);
697 void copy_scopes_data(address buffer, int size);
698
699 // Deopt
700 // Return true is the PC is one would expect if the frame is being deopted.
701 bool is_deopt_pc (address pc) { return is_deopt_entry(pc) || is_deopt_mh_entry(pc); }
702 bool is_deopt_entry (address pc);
703 bool is_deopt_mh_entry(address pc) { return pc == deopt_mh_handler_begin(); }
704 // Accessor/mutator for the original pc of a frame before a frame was deopted.
705 address get_original_pc(const frame* fr) { return *orig_pc_addr(fr); }
706 void set_original_pc(const frame* fr, address pc) { *orig_pc_addr(fr) = pc; }
707
708 static address get_deopt_original_pc(const frame* fr);
709
710 // MethodHandle
711 bool is_method_handle_return(address return_pc);
712
713 // jvmti support:
714 void post_compiled_method_load_event();
715 jmethodID get_and_cache_jmethod_id();
716
717 // verify operations
718 void verify();
719 void verify_scopes();
720 void verify_interrupt_point(address interrupt_point);
721
722 // printing support
723 void print() const;
724 void print_relocations() PRODUCT_RETURN;
725 void print_pcs() PRODUCT_RETURN;
726 void print_scopes() PRODUCT_RETURN;
727 void print_dependencies() PRODUCT_RETURN;
728 void print_value_on(outputStream* st) const PRODUCT_RETURN;
729 void print_calls(outputStream* st) PRODUCT_RETURN;
730 void print_handler_table() PRODUCT_RETURN;
731 void print_nul_chk_table() PRODUCT_RETURN;
732 void print_recorded_oops() PRODUCT_RETURN;
733 void print_recorded_metadata() PRODUCT_RETURN;
734
735 void maybe_print_nmethod(DirectiveSet* directive);
736 void print_nmethod(bool print_code);
737
738 // need to re-define this from CodeBlob else the overload hides it
739 virtual void print_on(outputStream* st) const { CodeBlob::print_on(st); }
740 void print_on(outputStream* st, const char* msg) const;
741
742 // Logging
743 void log_identity(xmlStream* log) const;
744 void log_new_nmethod() const;
745 void log_state_change() const;
746
747 // Prints block-level comments, including nmethod specific block labels:
748 virtual void print_block_comment(outputStream* stream, address block_begin) const {
749 print_nmethod_labels(stream, block_begin);
750 CodeBlob::print_block_comment(stream, block_begin);
751 }
752 void print_nmethod_labels(outputStream* stream, address block_begin) const;
753
754 // Prints a comment for one native instruction (reloc info, pc desc)
755 void print_code_comment_on(outputStream* st, int column, address begin, address end);
756 static void print_statistics() PRODUCT_RETURN;
757
758 // Compiler task identification. Note that all OSR methods
759 // are numbered in an independent sequence if CICountOSR is true,
760 // and native method wrappers are also numbered independently if
761 // CICountNative is true.
762 int compile_id() const { return _compile_id; }
763 const char* compile_kind() const;
764
765 // tells if any of this method's dependencies have been invalidated
766 // (this is expensive!)
767 static void check_all_dependencies(DepChange& changes);
768
769 // tells if this compiled method is dependent on the given changes,
770 // and the changes have invalidated it
771 bool check_dependency_on(DepChange& changes);
772
773 // Evolution support. Tells if this compiled method is dependent on any of
774 // methods m() of class dependee, such that if m() in dependee is replaced,
775 // this compiled method will have to be deoptimized.
776 bool is_evol_dependent_on(Klass* dependee);
777
778 // Fast breakpoint support. Tells if this compiled method is
779 // dependent on the given method. Returns true if this nmethod
780 // corresponds to the given method as well.
781 bool is_dependent_on_method(Method* dependee);
782
783 // is it ok to patch at address?
784 bool is_patchable_at(address instr_address);
785
786 // UseBiasedLocking support
787 ByteSize native_receiver_sp_offset() {
788 return _native_receiver_sp_offset;
789 }
790 ByteSize native_basic_lock_sp_offset() {
791 return _native_basic_lock_sp_offset;
792 }
793
794 // support for code generation
795 static int verified_entry_point_offset() { return offset_of(nmethod, _verified_entry_point); }
796 static int osr_entry_point_offset() { return offset_of(nmethod, _osr_entry_point); }
797 static int state_offset() { return offset_of(nmethod, _state); }
798
799 // RedefineClasses support. Mark metadata in nmethods as on_stack so that
800 // redefine classes doesn't purge it.
801 static void mark_on_stack(nmethod* nm) {
802 nm->metadata_do(Metadata::mark_on_stack);
803 }
804 void metadata_do(void f(Metadata*));
805 };
806
807 // Locks an nmethod so its code will not get removed and it will not
808 // be made into a zombie, even if it is a not_entrant method. After the
809 // nmethod becomes a zombie, if CompiledMethodUnload event processing
810 // needs to be done, then lock_nmethod() is used directly to keep the
811 // generated code from being reused too early.
812 class nmethodLocker : public StackObj {
813 nmethod* _nm;
814
815 public:
816
817 // note: nm can be NULL
818 // Only JvmtiDeferredEvent::compiled_method_unload_event()
819 // should pass zombie_ok == true.
820 static void lock_nmethod(nmethod* nm, bool zombie_ok = false);
821 static void unlock_nmethod(nmethod* nm); // (ditto)
822
823 nmethodLocker(address pc); // derive nm from pc
824 nmethodLocker(nmethod *nm) { _nm = nm; lock_nmethod(_nm); }
825 nmethodLocker() { _nm = NULL; }
826 ~nmethodLocker() { unlock_nmethod(_nm); }
827
828 nmethod* code() { return _nm; }
829 void set_code(nmethod* new_nm) {
830 unlock_nmethod(_nm); // note: This works even if _nm==new_nm.
831 _nm = new_nm;
832 lock_nmethod(_nm);
833 }
834 };
835
836 #endif // SHARE_VM_CODE_NMETHOD_HPP