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