Thu, 24 May 2018 18:41:44 +0800
Merge
1 /*
2 * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #ifndef SHARE_VM_CODE_NMETHOD_HPP
26 #define SHARE_VM_CODE_NMETHOD_HPP
28 #include "code/codeBlob.hpp"
29 #include "code/pcDesc.hpp"
30 #include "oops/metadata.hpp"
32 // This class is used internally by nmethods, to cache
33 // exception/pc/handler information.
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 volatile int _count;
43 ExceptionCache* _next;
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 OrderAccess::load_acquire(&_count); }
50 // increment_count is only called under lock, but there may be concurrent readers.
51 void increment_count() { OrderAccess::release_store(&_count, _count + 1); }
53 public:
55 ExceptionCache(Handle exception, address pc, address handler);
57 Klass* exception_type() { return _exception_type; }
58 ExceptionCache* next() { return _next; }
59 void set_next(ExceptionCache *ec) { _next = ec; }
61 address match(Handle exception, address pc);
62 bool match_exception_with_space(Handle exception) ;
63 address test_address(address addr);
64 bool add_address_and_handler(address addr, address handler) ;
65 };
68 // cache pc descs found in earlier inquiries
69 class PcDescCache VALUE_OBJ_CLASS_SPEC {
70 friend class VMStructs;
71 private:
72 enum { cache_size = 4 };
73 // The array elements MUST be volatile! Several threads may modify
74 // and read from the cache concurrently. find_pc_desc_internal has
75 // returned wrong results. C++ compiler (namely xlC12) may duplicate
76 // C++ field accesses if the elements are not volatile.
77 typedef PcDesc* PcDescPtr;
78 volatile PcDescPtr _pc_descs[cache_size]; // last cache_size pc_descs found
79 public:
80 PcDescCache() { debug_only(_pc_descs[0] = NULL); }
81 void reset_to(PcDesc* initial_pc_desc);
82 PcDesc* find_pc_desc(int pc_offset, bool approximate);
83 void add_pc_desc(PcDesc* pc_desc);
84 PcDesc* last_pc_desc() { return _pc_descs[0]; }
85 };
88 // nmethods (native methods) are the compiled code versions of Java methods.
89 //
90 // An nmethod contains:
91 // - header (the nmethod structure)
92 // [Relocation]
93 // - relocation information
94 // - constant part (doubles, longs and floats used in nmethod)
95 // - oop table
96 // [Code]
97 // - code body
98 // - exception handler
99 // - stub code
100 // [Debugging information]
101 // - oop array
102 // - data array
103 // - pcs
104 // [Exception handler table]
105 // - handler entry point array
106 // [Implicit Null Pointer exception table]
107 // - implicit null table array
109 class Dependencies;
110 class ExceptionHandlerTable;
111 class ImplicitExceptionTable;
112 class AbstractCompiler;
113 class xmlStream;
115 class nmethod : public CodeBlob {
116 friend class VMStructs;
117 friend class NMethodSweeper;
118 friend class CodeCache; // scavengable oops
119 private:
121 // GC support to help figure out if an nmethod has been
122 // cleaned/unloaded by the current GC.
123 static unsigned char _global_unloading_clock;
125 // Shared fields for all nmethod's
126 Method* _method;
127 int _entry_bci; // != InvocationEntryBci if this nmethod is an on-stack replacement method
128 jmethodID _jmethod_id; // Cache of method()->jmethod_id()
130 // To support simple linked-list chaining of nmethods:
131 nmethod* _osr_link; // from InstanceKlass::osr_nmethods_head
133 union {
134 // Used by G1 to chain nmethods.
135 nmethod* _unloading_next;
136 // Used by non-G1 GCs to chain nmethods.
137 nmethod* _scavenge_root_link; // from CodeCache::scavenge_root_nmethods
138 };
140 static nmethod* volatile _oops_do_mark_nmethods;
141 nmethod* volatile _oops_do_mark_link;
143 AbstractCompiler* _compiler; // The compiler which compiled this nmethod
145 // offsets for entry points
146 address _entry_point; // entry point with class check
147 address _verified_entry_point; // entry point without class check
148 address _osr_entry_point; // entry point for on stack replacement
150 // Offsets for different nmethod parts
151 int _exception_offset;
152 // All deoptee's will resume execution at this location described by
153 // this offset.
154 int _deoptimize_offset;
155 // All deoptee's at a MethodHandle call site will resume execution
156 // at this location described by this offset.
157 int _deoptimize_mh_offset;
158 // Offset of the unwind handler if it exists
159 int _unwind_handler_offset;
161 #ifdef HAVE_DTRACE_H
162 int _trap_offset;
163 #endif // def HAVE_DTRACE_H
164 int _consts_offset;
165 int _stub_offset;
166 int _oops_offset; // offset to where embedded oop table begins (inside data)
167 int _metadata_offset; // embedded meta data table
168 int _scopes_data_offset;
169 int _scopes_pcs_offset;
170 int _dependencies_offset;
171 int _handler_table_offset;
172 int _nul_chk_table_offset;
173 int _nmethod_end_offset;
175 // location in frame (offset for sp) that deopt can store the original
176 // pc during a deopt.
177 int _orig_pc_offset;
179 int _compile_id; // which compilation made this nmethod
180 int _comp_level; // compilation level
182 // protected by CodeCache_lock
183 bool _has_flushed_dependencies; // Used for maintenance of dependencies (CodeCache_lock)
185 bool _marked_for_reclamation; // Used by NMethodSweeper (set only by sweeper)
186 bool _marked_for_deoptimization; // Used for stack deoptimization
188 // used by jvmti to track if an unload event has been posted for this nmethod.
189 bool _unload_reported;
191 // set during construction
192 unsigned int _has_unsafe_access:1; // May fault due to unsafe access.
193 unsigned int _has_method_handle_invokes:1; // Has this method MethodHandle invokes?
194 unsigned int _lazy_critical_native:1; // Lazy JNI critical native
195 unsigned int _has_wide_vectors:1; // Preserve wide vectors at safepoints
197 // Protected by Patching_lock
198 volatile unsigned char _state; // {alive, not_entrant, zombie, unloaded}
200 volatile unsigned char _unloading_clock; // Incremented after GC unloaded/cleaned the nmethod
202 #ifdef ASSERT
203 bool _oops_are_stale; // indicates that it's no longer safe to access oops section
204 #endif
206 enum { in_use = 0, // executable nmethod
207 not_entrant = 1, // marked for deoptimization but activations may still exist,
208 // will be transformed to zombie when all activations are gone
209 zombie = 2, // no activations exist, nmethod is ready for purge
210 unloaded = 3 }; // there should be no activations, should not be called,
211 // will be transformed to zombie immediately
213 jbyte _scavenge_root_state;
215 #if INCLUDE_RTM_OPT
216 // RTM state at compile time. Used during deoptimization to decide
217 // whether to restart collecting RTM locking abort statistic again.
218 RTMState _rtm_state;
219 #endif
221 // Nmethod Flushing lock. If non-zero, then the nmethod is not removed
222 // and is not made into a zombie. However, once the nmethod is made into
223 // a zombie, it will be locked one final time if CompiledMethodUnload
224 // event processing needs to be done.
225 jint _lock_count;
227 // not_entrant method removal. Each mark_sweep pass will update
228 // this mark to current sweep invocation count if it is seen on the
229 // stack. An not_entrant method can be removed when there are no
230 // more activations, i.e., when the _stack_traversal_mark is less than
231 // current sweep traversal index.
232 long _stack_traversal_mark;
234 // The _hotness_counter indicates the hotness of a method. The higher
235 // the value the hotter the method. The hotness counter of a nmethod is
236 // set to [(ReservedCodeCacheSize / (1024 * 1024)) * 2] each time the method
237 // is active while stack scanning (mark_active_nmethods()). The hotness
238 // counter is decreased (by 1) while sweeping.
239 int _hotness_counter;
241 ExceptionCache * volatile _exception_cache;
242 PcDescCache _pc_desc_cache;
244 // These are used for compiled synchronized native methods to
245 // locate the owner and stack slot for the BasicLock so that we can
246 // properly revoke the bias of the owner if necessary. They are
247 // needed because there is no debug information for compiled native
248 // wrappers and the oop maps are insufficient to allow
249 // frame::retrieve_receiver() to work. Currently they are expected
250 // to be byte offsets from the Java stack pointer for maximum code
251 // sharing between platforms. Note that currently biased locking
252 // will never cause Class instances to be biased but this code
253 // handles the static synchronized case as well.
254 // JVMTI's GetLocalInstance() also uses these offsets to find the receiver
255 // for non-static native wrapper frames.
256 ByteSize _native_receiver_sp_offset;
257 ByteSize _native_basic_lock_sp_offset;
259 friend class nmethodLocker;
261 // For native wrappers
262 nmethod(Method* method,
263 int nmethod_size,
264 int compile_id,
265 CodeOffsets* offsets,
266 CodeBuffer *code_buffer,
267 int frame_size,
268 ByteSize basic_lock_owner_sp_offset, /* synchronized natives only */
269 ByteSize basic_lock_sp_offset, /* synchronized natives only */
270 OopMapSet* oop_maps);
272 #ifdef HAVE_DTRACE_H
273 // For native wrappers
274 nmethod(Method* method,
275 int nmethod_size,
276 CodeOffsets* offsets,
277 CodeBuffer *code_buffer,
278 int frame_size);
279 #endif // def HAVE_DTRACE_H
281 // Creation support
282 nmethod(Method* method,
283 int nmethod_size,
284 int compile_id,
285 int entry_bci,
286 CodeOffsets* offsets,
287 int orig_pc_offset,
288 DebugInformationRecorder *recorder,
289 Dependencies* dependencies,
290 CodeBuffer *code_buffer,
291 int frame_size,
292 OopMapSet* oop_maps,
293 ExceptionHandlerTable* handler_table,
294 ImplicitExceptionTable* nul_chk_table,
295 AbstractCompiler* compiler,
296 int comp_level);
298 // helper methods
299 void* operator new(size_t size, int nmethod_size) throw();
301 const char* reloc_string_for(u_char* begin, u_char* end);
302 // Returns true if this thread changed the state of the nmethod or
303 // false if another thread performed the transition.
304 bool make_not_entrant_or_zombie(unsigned int state);
305 void inc_decompile_count();
307 // Used to manipulate the exception cache
308 void add_exception_cache_entry(ExceptionCache* new_entry);
309 ExceptionCache* exception_cache_entry_for_exception(Handle exception);
311 // Inform external interfaces that a compiled method has been unloaded
312 void post_compiled_method_unload();
314 // Initailize fields to their default values
315 void init_defaults();
317 public:
318 // create nmethod with entry_bci
319 static nmethod* new_nmethod(methodHandle method,
320 int compile_id,
321 int entry_bci,
322 CodeOffsets* offsets,
323 int orig_pc_offset,
324 DebugInformationRecorder* recorder,
325 Dependencies* dependencies,
326 CodeBuffer *code_buffer,
327 int frame_size,
328 OopMapSet* oop_maps,
329 ExceptionHandlerTable* handler_table,
330 ImplicitExceptionTable* nul_chk_table,
331 AbstractCompiler* compiler,
332 int comp_level);
334 static nmethod* new_native_nmethod(methodHandle method,
335 int compile_id,
336 CodeBuffer *code_buffer,
337 int vep_offset,
338 int frame_complete,
339 int frame_size,
340 ByteSize receiver_sp_offset,
341 ByteSize basic_lock_sp_offset,
342 OopMapSet* oop_maps);
344 #ifdef HAVE_DTRACE_H
345 // The method we generate for a dtrace probe has to look
346 // like an nmethod as far as the rest of the system is concerned
347 // which is somewhat unfortunate.
348 static nmethod* new_dtrace_nmethod(methodHandle method,
349 CodeBuffer *code_buffer,
350 int vep_offset,
351 int trap_offset,
352 int frame_complete,
353 int frame_size);
355 int trap_offset() const { return _trap_offset; }
356 address trap_address() const { return insts_begin() + _trap_offset; }
358 #endif // def HAVE_DTRACE_H
360 // accessors
361 Method* method() const { return _method; }
362 AbstractCompiler* compiler() const { return _compiler; }
364 // type info
365 bool is_nmethod() const { return true; }
366 bool is_java_method() const { return !method()->is_native(); }
367 bool is_native_method() const { return method()->is_native(); }
368 bool is_osr_method() const { return _entry_bci != InvocationEntryBci; }
370 bool is_compiled_by_c1() const;
371 bool is_compiled_by_c2() const;
372 bool is_compiled_by_shark() const;
374 // boundaries for different parts
375 address consts_begin () const { return header_begin() + _consts_offset ; }
376 address consts_end () const { return header_begin() + code_offset() ; }
377 address insts_begin () const { return header_begin() + code_offset() ; }
378 address insts_end () const { return header_begin() + _stub_offset ; }
379 address stub_begin () const { return header_begin() + _stub_offset ; }
380 address stub_end () const { return header_begin() + _oops_offset ; }
381 address exception_begin () const { return header_begin() + _exception_offset ; }
382 address deopt_handler_begin () const { return header_begin() + _deoptimize_offset ; }
383 address deopt_mh_handler_begin() const { return header_begin() + _deoptimize_mh_offset ; }
384 address unwind_handler_begin () const { return _unwind_handler_offset != -1 ? (header_begin() + _unwind_handler_offset) : NULL; }
385 oop* oops_begin () const { return (oop*) (header_begin() + _oops_offset) ; }
386 oop* oops_end () const { return (oop*) (header_begin() + _metadata_offset) ; }
388 Metadata** metadata_begin () const { return (Metadata**) (header_begin() + _metadata_offset) ; }
389 Metadata** metadata_end () const { return (Metadata**) (header_begin() + _scopes_data_offset) ; }
391 address scopes_data_begin () const { return header_begin() + _scopes_data_offset ; }
392 address scopes_data_end () const { return header_begin() + _scopes_pcs_offset ; }
393 PcDesc* scopes_pcs_begin () const { return (PcDesc*)(header_begin() + _scopes_pcs_offset ); }
394 PcDesc* scopes_pcs_end () const { return (PcDesc*)(header_begin() + _dependencies_offset) ; }
395 address dependencies_begin () const { return header_begin() + _dependencies_offset ; }
396 address dependencies_end () const { return header_begin() + _handler_table_offset ; }
397 address handler_table_begin () const { return header_begin() + _handler_table_offset ; }
398 address handler_table_end () const { return header_begin() + _nul_chk_table_offset ; }
399 address nul_chk_table_begin () const { return header_begin() + _nul_chk_table_offset ; }
400 address nul_chk_table_end () const { return header_begin() + _nmethod_end_offset ; }
402 // Sizes
403 int consts_size () const { return consts_end () - consts_begin (); }
404 int insts_size () const { return insts_end () - insts_begin (); }
405 int stub_size () const { return stub_end () - stub_begin (); }
406 int oops_size () const { return (address) oops_end () - (address) oops_begin (); }
407 int metadata_size () const { return (address) metadata_end () - (address) metadata_begin (); }
408 int scopes_data_size () const { return scopes_data_end () - scopes_data_begin (); }
409 int scopes_pcs_size () const { return (intptr_t) scopes_pcs_end () - (intptr_t) scopes_pcs_begin (); }
410 int dependencies_size () const { return dependencies_end () - dependencies_begin (); }
411 int handler_table_size() const { return handler_table_end() - handler_table_begin(); }
412 int nul_chk_table_size() const { return nul_chk_table_end() - nul_chk_table_begin(); }
414 int total_size () const;
416 void dec_hotness_counter() { _hotness_counter--; }
417 void set_hotness_counter(int val) { _hotness_counter = val; }
418 int hotness_counter() const { return _hotness_counter; }
420 // Containment
421 bool consts_contains (address addr) const { return consts_begin () <= addr && addr < consts_end (); }
422 bool insts_contains (address addr) const { return insts_begin () <= addr && addr < insts_end (); }
423 bool stub_contains (address addr) const { return stub_begin () <= addr && addr < stub_end (); }
424 bool oops_contains (oop* addr) const { return oops_begin () <= addr && addr < oops_end (); }
425 bool metadata_contains (Metadata** addr) const { return metadata_begin () <= addr && addr < metadata_end (); }
426 bool scopes_data_contains (address addr) const { return scopes_data_begin () <= addr && addr < scopes_data_end (); }
427 bool scopes_pcs_contains (PcDesc* addr) const { return scopes_pcs_begin () <= addr && addr < scopes_pcs_end (); }
428 bool handler_table_contains(address addr) const { return handler_table_begin() <= addr && addr < handler_table_end(); }
429 bool nul_chk_table_contains(address addr) const { return nul_chk_table_begin() <= addr && addr < nul_chk_table_end(); }
431 // entry points
432 address entry_point() const { return _entry_point; } // normal entry point
433 address verified_entry_point() const { return _verified_entry_point; } // if klass is correct
435 // flag accessing and manipulation
436 bool is_in_use() const { return _state == in_use; }
437 bool is_alive() const { unsigned char s = _state; return s == in_use || s == not_entrant; }
438 bool is_not_entrant() const { return _state == not_entrant; }
439 bool is_zombie() const { return _state == zombie; }
440 bool is_unloaded() const { return _state == unloaded; }
442 #if INCLUDE_RTM_OPT
443 // rtm state accessing and manipulating
444 RTMState rtm_state() const { return _rtm_state; }
445 void set_rtm_state(RTMState state) { _rtm_state = state; }
446 #endif
448 // Make the nmethod non entrant. The nmethod will continue to be
449 // alive. It is used when an uncommon trap happens. Returns true
450 // if this thread changed the state of the nmethod or false if
451 // another thread performed the transition.
452 bool make_not_entrant() {
453 assert(!method()->is_method_handle_intrinsic(), "Cannot make MH intrinsic not entrant");
454 return make_not_entrant_or_zombie(not_entrant);
455 }
456 bool make_zombie() { return make_not_entrant_or_zombie(zombie); }
458 // used by jvmti to track if the unload event has been reported
459 bool unload_reported() { return _unload_reported; }
460 void set_unload_reported() { _unload_reported = true; }
462 void set_unloading_next(nmethod* next) { _unloading_next = next; }
463 nmethod* unloading_next() { return _unloading_next; }
465 static unsigned char global_unloading_clock() { return _global_unloading_clock; }
466 static void increase_unloading_clock();
468 void set_unloading_clock(unsigned char unloading_clock);
469 unsigned char unloading_clock();
471 bool is_marked_for_deoptimization() const { return _marked_for_deoptimization; }
472 void mark_for_deoptimization() { _marked_for_deoptimization = true; }
474 void make_unloaded(BoolObjectClosure* is_alive, oop cause);
476 bool has_dependencies() { return dependencies_size() != 0; }
477 void flush_dependencies(BoolObjectClosure* is_alive);
478 bool has_flushed_dependencies() { return _has_flushed_dependencies; }
479 void set_has_flushed_dependencies() {
480 assert(!has_flushed_dependencies(), "should only happen once");
481 _has_flushed_dependencies = 1;
482 }
484 bool is_marked_for_reclamation() const { return _marked_for_reclamation; }
485 void mark_for_reclamation() { _marked_for_reclamation = 1; }
487 bool has_unsafe_access() const { return _has_unsafe_access; }
488 void set_has_unsafe_access(bool z) { _has_unsafe_access = z; }
490 bool has_method_handle_invokes() const { return _has_method_handle_invokes; }
491 void set_has_method_handle_invokes(bool z) { _has_method_handle_invokes = z; }
493 bool is_lazy_critical_native() const { return _lazy_critical_native; }
494 void set_lazy_critical_native(bool z) { _lazy_critical_native = z; }
496 bool has_wide_vectors() const { return _has_wide_vectors; }
497 void set_has_wide_vectors(bool z) { _has_wide_vectors = z; }
499 int comp_level() const { return _comp_level; }
501 // Support for oops in scopes and relocs:
502 // Note: index 0 is reserved for null.
503 oop oop_at(int index) const { return index == 0 ? (oop) NULL: *oop_addr_at(index); }
504 oop* oop_addr_at(int index) const { // for GC
505 // relocation indexes are biased by 1 (because 0 is reserved)
506 assert(index > 0 && index <= oops_size(), "must be a valid non-zero index");
507 assert(!_oops_are_stale, "oops are stale");
508 return &oops_begin()[index - 1];
509 }
511 // Support for meta data in scopes and relocs:
512 // Note: index 0 is reserved for null.
513 Metadata* metadata_at(int index) const { return index == 0 ? NULL: *metadata_addr_at(index); }
514 Metadata** metadata_addr_at(int index) const { // for GC
515 // relocation indexes are biased by 1 (because 0 is reserved)
516 assert(index > 0 && index <= metadata_size(), "must be a valid non-zero index");
517 return &metadata_begin()[index - 1];
518 }
520 void copy_values(GrowableArray<jobject>* oops);
521 void copy_values(GrowableArray<Metadata*>* metadata);
523 // Relocation support
524 private:
525 void fix_oop_relocations(address begin, address end, bool initialize_immediates);
526 inline void initialize_immediate_oop(oop* dest, jobject handle);
528 public:
529 void fix_oop_relocations(address begin, address end) { fix_oop_relocations(begin, end, false); }
530 void fix_oop_relocations() { fix_oop_relocations(NULL, NULL, false); }
531 void verify_oop_relocations();
533 bool is_at_poll_return(address pc);
534 bool is_at_poll_or_poll_return(address pc);
536 // Scavengable oop support
537 bool on_scavenge_root_list() const { return (_scavenge_root_state & 1) != 0; }
538 protected:
539 enum { sl_on_list = 0x01, sl_marked = 0x10 };
540 void set_on_scavenge_root_list() { _scavenge_root_state = sl_on_list; }
541 void clear_on_scavenge_root_list() { _scavenge_root_state = 0; }
542 // assertion-checking and pruning logic uses the bits of _scavenge_root_state
543 #ifndef PRODUCT
544 void set_scavenge_root_marked() { _scavenge_root_state |= sl_marked; }
545 void clear_scavenge_root_marked() { _scavenge_root_state &= ~sl_marked; }
546 bool scavenge_root_not_marked() { return (_scavenge_root_state &~ sl_on_list) == 0; }
547 // N.B. there is no positive marked query, and we only use the not_marked query for asserts.
548 #endif //PRODUCT
549 nmethod* scavenge_root_link() const { return _scavenge_root_link; }
550 void set_scavenge_root_link(nmethod *n) { _scavenge_root_link = n; }
552 public:
554 // Sweeper support
555 long stack_traversal_mark() { return _stack_traversal_mark; }
556 void set_stack_traversal_mark(long l) { _stack_traversal_mark = l; }
558 // Exception cache support
559 // Note: _exception_cache may be read concurrently. We rely on memory_order_consume here.
560 ExceptionCache* exception_cache() const { return _exception_cache; }
561 void set_exception_cache(ExceptionCache *ec) { _exception_cache = ec; }
562 void release_set_exception_cache(ExceptionCache *ec) { OrderAccess::release_store_ptr(&_exception_cache, ec); }
563 address handler_for_exception_and_pc(Handle exception, address pc);
564 void add_handler_for_exception_and_pc(Handle exception, address pc, address handler);
565 void clean_exception_cache(BoolObjectClosure* is_alive);
567 // implicit exceptions support
568 address continuation_for_implicit_exception(address pc);
570 // On-stack replacement support
571 int osr_entry_bci() const { assert(is_osr_method(), "wrong kind of nmethod"); return _entry_bci; }
572 address osr_entry() const { assert(is_osr_method(), "wrong kind of nmethod"); return _osr_entry_point; }
573 void invalidate_osr_method();
574 nmethod* osr_link() const { return _osr_link; }
575 void set_osr_link(nmethod *n) { _osr_link = n; }
577 // tells whether frames described by this nmethod can be deoptimized
578 // note: native wrappers cannot be deoptimized.
579 bool can_be_deoptimized() const { return is_java_method(); }
581 // Inline cache support
582 void clear_inline_caches();
583 void clear_ic_stubs();
584 void cleanup_inline_caches();
585 bool inlinecache_check_contains(address addr) const {
586 return (addr >= code_begin() && addr < verified_entry_point());
587 }
589 // Verify calls to dead methods have been cleaned.
590 void verify_clean_inline_caches();
591 // Verify and count cached icholder relocations.
592 int verify_icholder_relocations();
593 // Check that all metadata is still alive
594 void verify_metadata_loaders(address low_boundary, BoolObjectClosure* is_alive);
596 // unlink and deallocate this nmethod
597 // Only NMethodSweeper class is expected to use this. NMethodSweeper is not
598 // expected to use any other private methods/data in this class.
600 protected:
601 void flush();
603 public:
604 // When true is returned, it is unsafe to remove this nmethod even if
605 // it is a zombie, since the VM or the ServiceThread might still be
606 // using it.
607 bool is_locked_by_vm() const { return _lock_count >0; }
609 // See comment at definition of _last_seen_on_stack
610 void mark_as_seen_on_stack();
611 bool can_convert_to_zombie();
613 // Evolution support. We make old (discarded) compiled methods point to new Method*s.
614 void set_method(Method* method) { _method = method; }
616 // GC support
617 void do_unloading(BoolObjectClosure* is_alive, bool unloading_occurred);
618 // The parallel versions are used by G1.
619 bool do_unloading_parallel(BoolObjectClosure* is_alive, bool unloading_occurred);
620 void do_unloading_parallel_postponed(BoolObjectClosure* is_alive, bool unloading_occurred);
622 private:
623 // Unload a nmethod if the *root object is dead.
624 bool can_unload(BoolObjectClosure* is_alive, oop* root, bool unloading_occurred);
625 bool unload_if_dead_at(RelocIterator *iter_at_oop, BoolObjectClosure* is_alive, bool unloading_occurred);
627 void mark_metadata_on_stack_at(RelocIterator* iter_at_metadata);
628 void mark_metadata_on_stack_non_relocs();
630 public:
631 void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map,
632 OopClosure* f);
633 void oops_do(OopClosure* f) { oops_do(f, false); }
634 void oops_do(OopClosure* f, bool allow_zombie);
635 bool detect_scavenge_root_oops();
636 void verify_scavenge_root_oops() PRODUCT_RETURN;
638 bool test_set_oops_do_mark();
639 static void oops_do_marking_prologue();
640 static void oops_do_marking_epilogue();
641 static bool oops_do_marking_is_active() { return _oops_do_mark_nmethods != NULL; }
642 bool test_oops_do_mark() { return _oops_do_mark_link != NULL; }
644 // ScopeDesc for an instruction
645 ScopeDesc* scope_desc_at(address pc);
647 private:
648 ScopeDesc* scope_desc_in(address begin, address end);
650 address* orig_pc_addr(const frame* fr) { return (address*) ((address)fr->unextended_sp() + _orig_pc_offset); }
652 PcDesc* find_pc_desc_internal(address pc, bool approximate);
654 PcDesc* find_pc_desc(address pc, bool approximate) {
655 PcDesc* desc = _pc_desc_cache.last_pc_desc();
656 if (desc != NULL && desc->pc_offset() == pc - code_begin()) {
657 return desc;
658 }
659 return find_pc_desc_internal(pc, approximate);
660 }
662 public:
663 // ScopeDesc retrieval operation
664 PcDesc* pc_desc_at(address pc) { return find_pc_desc(pc, false); }
665 // pc_desc_near returns the first PcDesc at or after the givne pc.
666 PcDesc* pc_desc_near(address pc) { return find_pc_desc(pc, true); }
668 public:
669 // copying of debugging information
670 void copy_scopes_pcs(PcDesc* pcs, int count);
671 void copy_scopes_data(address buffer, int size);
673 // Deopt
674 // Return true is the PC is one would expect if the frame is being deopted.
675 bool is_deopt_pc (address pc) { return is_deopt_entry(pc) || is_deopt_mh_entry(pc); }
676 bool is_deopt_entry (address pc) { return pc == deopt_handler_begin(); }
677 bool is_deopt_mh_entry(address pc) { return pc == deopt_mh_handler_begin(); }
678 // Accessor/mutator for the original pc of a frame before a frame was deopted.
679 address get_original_pc(const frame* fr) { return *orig_pc_addr(fr); }
680 void set_original_pc(const frame* fr, address pc) { *orig_pc_addr(fr) = pc; }
682 static address get_deopt_original_pc(const frame* fr);
684 // MethodHandle
685 bool is_method_handle_return(address return_pc);
687 // jvmti support:
688 void post_compiled_method_load_event();
689 jmethodID get_and_cache_jmethod_id();
691 // verify operations
692 void verify();
693 void verify_scopes();
694 void verify_interrupt_point(address interrupt_point);
696 // printing support
697 void print() const;
698 void print_code();
699 void print_relocations() PRODUCT_RETURN;
700 void print_pcs() PRODUCT_RETURN;
701 void print_scopes() PRODUCT_RETURN;
702 void print_dependencies() PRODUCT_RETURN;
703 void print_value_on(outputStream* st) const PRODUCT_RETURN;
704 void print_calls(outputStream* st) PRODUCT_RETURN;
705 void print_handler_table() PRODUCT_RETURN;
706 void print_nul_chk_table() PRODUCT_RETURN;
707 void print_nmethod(bool print_code);
709 // need to re-define this from CodeBlob else the overload hides it
710 virtual void print_on(outputStream* st) const { CodeBlob::print_on(st); }
711 void print_on(outputStream* st, const char* msg) const;
713 // Logging
714 void log_identity(xmlStream* log) const;
715 void log_new_nmethod() const;
716 void log_state_change() const;
718 // Prints block-level comments, including nmethod specific block labels:
719 virtual void print_block_comment(outputStream* stream, address block_begin) const {
720 print_nmethod_labels(stream, block_begin);
721 CodeBlob::print_block_comment(stream, block_begin);
722 }
723 void print_nmethod_labels(outputStream* stream, address block_begin) const;
725 // Prints a comment for one native instruction (reloc info, pc desc)
726 void print_code_comment_on(outputStream* st, int column, address begin, address end);
727 static void print_statistics() PRODUCT_RETURN;
729 // Compiler task identification. Note that all OSR methods
730 // are numbered in an independent sequence if CICountOSR is true,
731 // and native method wrappers are also numbered independently if
732 // CICountNative is true.
733 int compile_id() const { return _compile_id; }
734 const char* compile_kind() const;
736 // For debugging
737 // CompiledIC* IC_at(char* p) const;
738 // PrimitiveIC* primitiveIC_at(char* p) const;
739 oop embeddedOop_at(address p);
741 // tells if any of this method's dependencies have been invalidated
742 // (this is expensive!)
743 bool check_all_dependencies();
745 // tells if this compiled method is dependent on the given changes,
746 // and the changes have invalidated it
747 bool check_dependency_on(DepChange& changes);
749 // Evolution support. Tells if this compiled method is dependent on any of
750 // methods m() of class dependee, such that if m() in dependee is replaced,
751 // this compiled method will have to be deoptimized.
752 bool is_evol_dependent_on(Klass* dependee);
754 // Fast breakpoint support. Tells if this compiled method is
755 // dependent on the given method. Returns true if this nmethod
756 // corresponds to the given method as well.
757 bool is_dependent_on_method(Method* dependee);
759 // is it ok to patch at address?
760 bool is_patchable_at(address instr_address);
762 // UseBiasedLocking support
763 ByteSize native_receiver_sp_offset() {
764 return _native_receiver_sp_offset;
765 }
766 ByteSize native_basic_lock_sp_offset() {
767 return _native_basic_lock_sp_offset;
768 }
770 // support for code generation
771 static int verified_entry_point_offset() { return offset_of(nmethod, _verified_entry_point); }
772 static int osr_entry_point_offset() { return offset_of(nmethod, _osr_entry_point); }
773 static int entry_bci_offset() { return offset_of(nmethod, _entry_bci); }
775 // RedefineClasses support. Mark metadata in nmethods as on_stack so that
776 // redefine classes doesn't purge it.
777 static void mark_on_stack(nmethod* nm) {
778 nm->metadata_do(Metadata::mark_on_stack);
779 }
780 void metadata_do(void f(Metadata*));
781 };
783 // Locks an nmethod so its code will not get removed and it will not
784 // be made into a zombie, even if it is a not_entrant method. After the
785 // nmethod becomes a zombie, if CompiledMethodUnload event processing
786 // needs to be done, then lock_nmethod() is used directly to keep the
787 // generated code from being reused too early.
788 class nmethodLocker : public StackObj {
789 nmethod* _nm;
791 public:
793 // note: nm can be NULL
794 // Only JvmtiDeferredEvent::compiled_method_unload_event()
795 // should pass zombie_ok == true.
796 static void lock_nmethod(nmethod* nm, bool zombie_ok = false);
797 static void unlock_nmethod(nmethod* nm); // (ditto)
799 nmethodLocker(address pc); // derive nm from pc
800 nmethodLocker(nmethod *nm) { _nm = nm; lock_nmethod(_nm); }
801 nmethodLocker() { _nm = NULL; }
802 ~nmethodLocker() { unlock_nmethod(_nm); }
804 nmethod* code() { return _nm; }
805 void set_code(nmethod* new_nm) {
806 unlock_nmethod(_nm); // note: This works even if _nm==new_nm.
807 _nm = new_nm;
808 lock_nmethod(_nm);
809 }
810 };
812 #endif // SHARE_VM_CODE_NMETHOD_HPP