1 /*
2 * Copyright (c) 1997, 2026, 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_OOPS_METHOD_HPP
26 #define SHARE_OOPS_METHOD_HPP
27
28 #include "code/compressedStream.hpp"
29 #include "compiler/compilerDefinitions.hpp"
30 #include "oops/annotations.hpp"
31 #include "oops/constantPool.hpp"
32 #include "oops/instanceKlass.hpp"
33 #include "oops/methodFlags.hpp"
34 #include "oops/oop.hpp"
35 #include "utilities/accessFlags.hpp"
36 #include "utilities/align.hpp"
37 #include "utilities/growableArray.hpp"
38 #include "utilities/macros.hpp"
39 #include "utilities/vmEnums.hpp"
40 #if INCLUDE_JFR
41 #include "jfr/support/jfrTraceIdExtension.hpp"
42 #endif
43
44
45 // A Method represents a Java method.
46 //
47 // Note that most applications load thousands of methods, so keeping the size of this
48 // class small has a big impact on footprint.
49 //
50 // Note that native_function and signature_handler have to be at fixed offsets
51 // (required by the interpreter)
52 //
53 // Method embedded field layout (after declared fields):
54 // [EMBEDDED native_function (present only if native) ]
55 // [EMBEDDED signature_handler (present only if native) ]
56
57 class CheckedExceptionElement;
58 class LocalVariableTableElement;
59 class AdapterHandlerEntry;
60 class MethodData;
61 class MethodCounters;
62 class MethodTrainingData;
63 class ConstMethod;
64 class InlineTableSizes;
65 class nmethod;
66 class InterpreterOopMap;
67
68 class Method : public Metadata {
69 friend class VMStructs;
70 friend class MethodTest;
71 private:
72 // If you add a new field that points to any metaspace object, you
73 // must add this field to Method::metaspace_pointers_do().
74 ConstMethod* _constMethod; // Method read-only data.
75 MethodData* _method_data;
76 MethodCounters* _method_counters;
77 AdapterHandlerEntry* _adapter;
78 int _vtable_index; // vtable index of this method (see VtableIndexFlag)
79 AccessFlags _access_flags; // Access flags
80 MethodFlags _flags;
81
82 u2 _intrinsic_id; // vmSymbols::intrinsic_id (0 == _none)
83
84 JFR_ONLY(DEFINE_TRACE_FLAG;)
85
86 #ifndef PRODUCT
87 int64_t _compiled_invocation_count;
88
89 Symbol* _name;
90 #endif
91 // Entry point for calling both from and to the interpreter.
92 address _i2i_entry; // All-args-on-stack calling convention
93 // Entry point for calling from compiled code, to compiled code if it exists
94 // or else the interpreter.
95 volatile address _from_compiled_entry; // Cache of: _code ? _code->entry_point() : _adapter->c2i_entry()
96 volatile address _from_compiled_inline_ro_entry; // Cache of: _code ? _code->verified_inline_ro_entry_point() : _adapter->c2i_inline_ro_entry()
97 volatile address _from_compiled_inline_entry; // Cache of: _code ? _code->verified_inline_entry_point() : _adapter->c2i_inline_entry()
98 // The entry point for calling both from and to compiled code is
99 // "_code->entry_point()". Because of tiered compilation and de-opt, this
100 // field can come and go. It can transition from null to not-null at any
101 // time (whenever a compile completes). It can transition from not-null to
102 // null only at safepoints (because of a de-opt).
103 nmethod* volatile _code; // Points to the corresponding piece of native code
104 volatile address _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry
105
106 // Constructor
107 Method(ConstMethod* xconst, AccessFlags access_flags, Symbol* name);
108 public:
109
110 static Method* allocate(ClassLoaderData* loader_data,
111 int byte_code_size,
112 AccessFlags access_flags,
113 InlineTableSizes* sizes,
114 ConstMethod::MethodType method_type,
115 Symbol* name,
116 TRAPS);
117
118 // CDS and vtbl checking can create an empty Method to get vtbl pointer.
119 Method(){}
120
121 virtual bool is_method() const { return true; }
122
123 #if INCLUDE_CDS
124 void remove_unshareable_info();
125 void restore_unshareable_info(TRAPS);
126 static void restore_archived_method_handle_intrinsic(methodHandle m, TRAPS);
127 #endif
128
129 // accessors for instance variables
130
131 ConstMethod* constMethod() const { return _constMethod; }
132 void set_constMethod(ConstMethod* xconst) { _constMethod = xconst; }
133
134
135 static void make_adapters(const methodHandle& mh, TRAPS);
136 address from_compiled_entry() const;
137 address from_compiled_inline_ro_entry() const;
138 address from_compiled_inline_entry() const;
139 address from_interpreted_entry() const;
140
141 // access flag
142 AccessFlags access_flags() const { return _access_flags; }
143 void set_access_flags(AccessFlags flags) { _access_flags = flags; }
144
145 // name
146 Symbol* name() const { return constants()->symbol_at(name_index()); }
147 u2 name_index() const { return constMethod()->name_index(); }
148 void set_name_index(int index) { constMethod()->set_name_index(index); }
149
150 // signature
151 Symbol* signature() const { return constants()->symbol_at(signature_index()); }
152 u2 signature_index() const { return constMethod()->signature_index(); }
153 void set_signature_index(int index) { constMethod()->set_signature_index(index); }
154
155 // generics support
156 Symbol* generic_signature() const { int idx = generic_signature_index(); return ((idx != 0) ? constants()->symbol_at(idx) : nullptr); }
157 u2 generic_signature_index() const { return constMethod()->generic_signature_index(); }
158
159 // annotations support
160 AnnotationArray* annotations() const {
161 return constMethod()->method_annotations();
162 }
163 AnnotationArray* parameter_annotations() const {
164 return constMethod()->parameter_annotations();
165 }
166 AnnotationArray* annotation_default() const {
167 return constMethod()->default_annotations();
168 }
169 AnnotationArray* type_annotations() const {
170 return constMethod()->type_annotations();
171 }
172
173 // Helper routine: get klass name + "." + method name + signature as
174 // C string, for the purpose of providing more useful
175 // fatal error handling. The string is allocated in resource
176 // area if a buffer is not provided by the caller.
177 char* name_and_sig_as_C_string(bool use_double_colon = false) const;
178 char* name_and_sig_as_C_string(char* buf, int size) const;
179
180 // Static routine in the situations we don't have a Method*
181 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, bool use_double_colon = false);
182 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);
183
184 // Get return type + klass name + "." + method name + ( parameters types )
185 // as a C string or print it to an outputStream.
186 // This is to be used to assemble strings passed to Java, so that
187 // the text more resembles Java code. Used in exception messages.
188 // Memory is allocated in the resource area; the caller needs
189 // a ResourceMark.
190 const char* external_name() const;
191 void print_external_name(outputStream *os) const;
192
193 static const char* external_name( Klass* klass, Symbol* method_name, Symbol* signature);
194 static void print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature);
195
196 Bytecodes::Code java_code_at(int bci) const {
197 return Bytecodes::java_code_at(this, bcp_from(bci));
198 }
199 Bytecodes::Code code_at(int bci) const {
200 return Bytecodes::code_at(this, bcp_from(bci));
201 }
202
203 // JVMTI breakpoints
204 #if !INCLUDE_JVMTI
205 Bytecodes::Code orig_bytecode_at(int bci) const {
206 ShouldNotReachHere();
207 return Bytecodes::_shouldnotreachhere;
208 }
209 void set_orig_bytecode_at(int bci, Bytecodes::Code code) {
210 ShouldNotReachHere();
211 };
212 u2 number_of_breakpoints() const {return 0;}
213 #else // !INCLUDE_JVMTI
214 Bytecodes::Code orig_bytecode_at(int bci) const;
215 void set_orig_bytecode_at(int bci, Bytecodes::Code code);
216 void set_breakpoint(int bci);
217 void clear_breakpoint(int bci);
218 void clear_all_breakpoints();
219 // Tracking number of breakpoints, for fullspeed debugging.
220 // Only mutated by VM thread.
221 inline u2 number_of_breakpoints() const;
222 inline void incr_number_of_breakpoints(Thread* current);
223 inline void decr_number_of_breakpoints(Thread* current);
224 // Initialization only
225 inline void clear_number_of_breakpoints();
226 #endif // !INCLUDE_JVMTI
227
228 // index into InstanceKlass methods() array
229 // note: also used by jfr
230 u2 method_idnum() const { return constMethod()->method_idnum(); }
231 void set_method_idnum(u2 idnum) { constMethod()->set_method_idnum(idnum); }
232
233 u2 orig_method_idnum() const { return constMethod()->orig_method_idnum(); }
234 void set_orig_method_idnum(u2 idnum) { constMethod()->set_orig_method_idnum(idnum); }
235
236 // code size
237 u2 code_size() const { return constMethod()->code_size(); }
238
239 // method size in words
240 int method_size() const { return sizeof(Method)/wordSize + ( is_native() ? 2 : 0 ); }
241
242 // constant pool for Klass* holding this method
243 ConstantPool* constants() const { return constMethod()->constants(); }
244 void set_constants(ConstantPool* c) { constMethod()->set_constants(c); }
245
246 // max stack
247 // return original max stack size for method verification
248 u2 verifier_max_stack() const { return constMethod()->max_stack(); }
249 int max_stack() const { return constMethod()->max_stack() + extra_stack_entries(); }
250 void set_max_stack(int size) { constMethod()->set_max_stack(size); }
251
252 // max locals
253 u2 max_locals() const { return constMethod()->max_locals(); }
254 void set_max_locals(int size) { constMethod()->set_max_locals(size); }
255
256 void set_deprecated() { constMethod()->set_deprecated(); }
257 bool deprecated() const { return constMethod()->deprecated(); }
258
259 void set_deprecated_for_removal() { constMethod()->set_deprecated_for_removal(); }
260 bool deprecated_for_removal() const { return constMethod()->deprecated_for_removal(); }
261
262 inline int highest_comp_level() const;
263 void set_highest_comp_level(int level);
264 int highest_osr_comp_level() const;
265 void set_highest_osr_comp_level(int level);
266
267 #ifdef COMPILER2
268 // Count of times method was exited via exception while interpreting
269 inline void interpreter_throwout_increment(Thread* current);
270 #endif // COMPILER2
271
272 inline int interpreter_throwout_count() const;
273
274 u2 size_of_parameters() const { return constMethod()->size_of_parameters(); }
275
276 bool has_stackmap_table() const {
277 return constMethod()->has_stackmap_table();
278 }
279
280 Array<u1>* stackmap_data() const {
281 return constMethod()->stackmap_data();
282 }
283
284 void set_stackmap_data(Array<u1>* sd) {
285 constMethod()->set_stackmap_data(sd);
286 }
287
288 // exception handler table
289 bool has_exception_handler() const
290 { return constMethod()->has_exception_table(); }
291 u2 exception_table_length() const
292 { return constMethod()->exception_table_length(); }
293 ExceptionTableElement* exception_table_start() const
294 { return constMethod()->exception_table_start(); }
295
296 // Finds the first entry point bci of an exception handler for an
297 // exception of klass ex_klass thrown at throw_bci. A value of null
298 // for ex_klass indicates that the exception klass is not known; in
299 // this case it matches any constraint class. Returns -1 if the
300 // exception cannot be handled in this method. The handler
301 // constraint classes are loaded if necessary. Note that this may
302 // throw an exception if loading of the constraint classes causes
303 // an IllegalAccessError (bugid 4307310) or an OutOfMemoryError.
304 // If an exception is thrown, returns the bci of the
305 // exception handler which caused the exception to be thrown, which
306 // is needed for proper retries. See, for example,
307 // InterpreterRuntime::exception_handler_for_exception.
308 static int fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS);
309
310 static bool register_native(Klass* k,
311 Symbol* name,
312 Symbol* signature,
313 address entry,
314 TRAPS);
315
316 // method data access
317 MethodData* method_data() const {
318 return _method_data;
319 }
320 void set_method_data(MethodData* data);
321
322 MethodTrainingData* training_data_or_null() const;
323 bool init_training_data(MethodTrainingData* td);
324
325 // mark an exception handler as entered (used to prune dead catch blocks in C2)
326 void set_exception_handler_entered(int handler_bci);
327
328 MethodCounters* method_counters() const {
329 return _method_counters;
330 }
331
332 void clear_method_counters() {
333 _method_counters = nullptr;
334 }
335
336 bool init_method_counters(MethodCounters* counters);
337
338 inline int prev_event_count() const;
339 inline void set_prev_event_count(int count);
340 inline jlong prev_time() const;
341 inline void set_prev_time(jlong time);
342 inline float rate() const;
343 inline void set_rate(float rate);
344
345 inline int invocation_count() const;
346 inline int backedge_count() const;
347
348 bool was_executed_more_than(int n);
349 bool was_never_executed() { return !was_executed_more_than(0); }
350
351 static void build_profiling_method_data(const methodHandle& method, TRAPS);
352 static bool install_training_method_data(const methodHandle& method);
353 static MethodCounters* build_method_counters(Thread* current, Method* m);
354
355 inline int interpreter_invocation_count() const;
356
357 #ifndef PRODUCT
358 int64_t compiled_invocation_count() const { return _compiled_invocation_count;}
359 void set_compiled_invocation_count(int count) { _compiled_invocation_count = (int64_t)count; }
360 #else
361 // for PrintMethodData in a product build
362 int64_t compiled_invocation_count() const { return 0; }
363 #endif // not PRODUCT
364
365 // nmethod/verified compiler entry
366 address verified_code_entry();
367 address verified_inline_code_entry();
368 address verified_inline_ro_code_entry();
369 bool check_code() const; // Not inline to avoid circular ref
370 nmethod* code() const;
371
372 // Locks NMethodState_lock if not held.
373 void unlink_code(nmethod *compare);
374 // Locks NMethodState_lock if not held.
375 void unlink_code();
376
377 private:
378 // Either called with NMethodState_lock held or from constructor.
379 void clear_code();
380
381 void clear_method_data() {
382 _method_data = nullptr;
383 }
384
385 public:
386 static void set_code(const methodHandle& mh, nmethod* code);
387 void set_adapter_entry(AdapterHandlerEntry* adapter) {
388 _adapter = adapter;
389 }
390 void set_from_compiled_entry(address entry) {
391 _from_compiled_entry = entry;
392 }
393 void set_from_compiled_inline_ro_entry(address entry) {
394 _from_compiled_inline_ro_entry = entry;
395 }
396 void set_from_compiled_inline_entry(address entry) {
397 _from_compiled_inline_entry = entry;
398 }
399
400 address get_i2c_entry();
401 address get_c2i_entry();
402 address get_c2i_inline_entry();
403 address get_c2i_inline_ro_entry();
404 address get_c2i_unverified_entry();
405 address get_c2i_unverified_inline_entry();
406 address get_c2i_no_clinit_check_entry();
407 AdapterHandlerEntry* adapter() const {
408 return _adapter;
409 }
410 // setup entry points
411 void link_method(const methodHandle& method, TRAPS);
412 // clear entry points. Used by sharing code during dump time
413 void unlink_method() NOT_CDS_RETURN;
414 void remove_unshareable_flags() NOT_CDS_RETURN;
415
416 virtual void metaspace_pointers_do(MetaspaceClosure* iter);
417 virtual MetaspaceObj::Type type() const { return MethodType; }
418
419 // vtable index
420 enum VtableIndexFlag {
421 // Valid vtable indexes are non-negative (>= 0).
422 // These few negative values are used as sentinels.
423 itable_index_max = -10, // first itable index, growing downward
424 pending_itable_index = -9, // itable index will be assigned
425 invalid_vtable_index = -4, // distinct from any valid vtable index
426 garbage_vtable_index = -3, // not yet linked; no vtable layout yet
427 nonvirtual_vtable_index = -2 // there is no need for vtable dispatch
428 // 6330203 Note: Do not use -1, which was overloaded with many meanings.
429 };
430 DEBUG_ONLY(bool valid_vtable_index() const { return _vtable_index >= nonvirtual_vtable_index; })
431 bool has_vtable_index() const { return _vtable_index >= 0; }
432 int vtable_index() const { return _vtable_index; }
433 void set_vtable_index(int index);
434 DEBUG_ONLY(bool valid_itable_index() const { return _vtable_index <= pending_itable_index; })
435 bool has_itable_index() const { return _vtable_index <= itable_index_max; }
436 int itable_index() const { assert(valid_itable_index(), "");
437 return itable_index_max - _vtable_index; }
438 void set_itable_index(int index);
439
440 // interpreter entry
441 address interpreter_entry() const { return _i2i_entry; }
442 // Only used when first initialize so we can set _i2i_entry and _from_interpreted_entry
443 void set_interpreter_entry(address entry) {
444 if (_i2i_entry != entry) {
445 _i2i_entry = entry;
446 }
447 if (_from_interpreted_entry != entry) {
448 _from_interpreted_entry = entry;
449 }
450 }
451
452 // native function (used for native methods only)
453 enum {
454 native_bind_event_is_interesting = true
455 };
456 address native_function() const { return *(native_function_addr()); }
457
458 // Must specify a real function (not null).
459 // Use clear_native_function() to unregister.
460 void set_native_function(address function, bool post_event_flag);
461 bool has_native_function() const;
462 void clear_native_function();
463
464 // signature handler (used for native methods only)
465 address signature_handler() const { return *(signature_handler_addr()); }
466 void set_signature_handler(address handler);
467
468 // Interpreter oopmap support.
469 // If handle is already available, call with it for better performance.
470 void mask_for(int bci, InterpreterOopMap* mask);
471 void mask_for(const methodHandle& this_mh, int bci, InterpreterOopMap* mask);
472
473 // operations on invocation counter
474 void print_invocation_count(outputStream* st);
475
476 // byte codes
477 void set_code(address code) { return constMethod()->set_code(code); }
478 address code_base() const { return constMethod()->code_base(); }
479 bool contains(address bcp) const { return constMethod()->contains(bcp); }
480
481 // prints byte codes
482 void print_codes(int flags = 0, bool buffered = true) const { print_codes_on(tty, flags, buffered); }
483 void print_codes_on(outputStream* st, int flags = 0, bool buffered = true) const;
484 void print_codes_on(int from, int to, outputStream* st, int flags = 0, bool buffered = true) const;
485
486 // method parameters
487 bool has_method_parameters() const
488 { return constMethod()->has_method_parameters(); }
489 int method_parameters_length() const
490 { return constMethod()->method_parameters_length(); }
491 MethodParametersElement* method_parameters_start() const
492 { return constMethod()->method_parameters_start(); }
493
494 // checked exceptions
495 u2 checked_exceptions_length() const
496 { return constMethod()->checked_exceptions_length(); }
497 CheckedExceptionElement* checked_exceptions_start() const
498 { return constMethod()->checked_exceptions_start(); }
499
500 // localvariable table
501 bool has_localvariable_table() const
502 { return constMethod()->has_localvariable_table(); }
503 u2 localvariable_table_length() const
504 { return constMethod()->localvariable_table_length(); }
505 LocalVariableTableElement* localvariable_table_start() const
506 { return constMethod()->localvariable_table_start(); }
507
508 bool has_linenumber_table() const
509 { return constMethod()->has_linenumber_table(); }
510 u_char* compressed_linenumber_table() const
511 { return constMethod()->compressed_linenumber_table(); }
512
513 // method holder (the Klass* holding this method)
514 InstanceKlass* method_holder() const { return constants()->pool_holder(); }
515
516 Symbol* klass_name() const; // returns the name of the method holder
517 BasicType result_type() const { return constMethod()->result_type(); }
518 bool is_returning_oop() const { BasicType r = result_type(); return is_reference_type(r); }
519 InlineKlass* returns_inline_type() const;
520
521 // Checked exceptions thrown by this method (resolved to mirrors)
522 objArrayHandle resolved_checked_exceptions(TRAPS) { return resolved_checked_exceptions_impl(this, THREAD); }
523
524 // Access flags
525 bool is_public() const { return access_flags().is_public(); }
526 bool is_private() const { return access_flags().is_private(); }
527 bool is_protected() const { return access_flags().is_protected(); }
528 bool is_package_private() const { return !is_public() && !is_private() && !is_protected(); }
529 bool is_static() const { return access_flags().is_static(); }
530 bool is_final() const { return access_flags().is_final(); }
531 bool is_synchronized() const { return access_flags().is_synchronized();}
532 bool is_native() const { return access_flags().is_native(); }
533 bool is_abstract() const { return access_flags().is_abstract(); }
534 bool is_synthetic() const { return access_flags().is_synthetic(); }
535
536 // returns true if contains only return operation
537 bool is_empty_method() const;
538
539 // returns true if this is a vanilla constructor
540 bool is_vanilla_constructor() const;
541
542 // checks method and its method holder
543 bool is_final_method() const;
544 bool is_final_method(AccessFlags class_access_flags) const;
545 // interface method declared with 'default' - excludes private interface methods
546 bool is_default_method() const;
547
548 // true if method needs no dynamic dispatch (final and/or no vtable entry)
549 bool can_be_statically_bound() const;
550 bool can_be_statically_bound(InstanceKlass* context) const;
551 bool can_be_statically_bound(AccessFlags class_access_flags) const;
552
553 // true if method can omit stack trace in throw in compiled code.
554 bool can_omit_stack_trace();
555
556 // Flags getting and setting.
557 #define M_STATUS_GET_SET(name, ignore) \
558 bool name() const { return _flags.name(); } \
559 void set_##name(bool x) { _flags.set_##name(x); } \
560 void set_##name() { _flags.set_##name(true); }
561 M_STATUS_DO(M_STATUS_GET_SET)
562 #undef M_STATUS_GET_SET
563
564 // returns true if the method has any backward branches.
565 bool has_loops() {
566 return has_loops_flag_init() ? has_loops_flag() : compute_has_loops_flag();
567 };
568
569 bool compute_has_loops_flag();
570 bool set_has_loops() {
571 // set both the flags and that it's been initialized.
572 set_has_loops_flag();
573 set_has_loops_flag_init();
574 return true;
575 }
576
577 // returns true if the method has any monitors.
578 bool has_monitors() const { return is_synchronized() || has_monitor_bytecodes(); }
579
580 // monitor matching. This returns a conservative estimate of whether the monitorenter/monitorexit bytecodes
581 // properly nest in the method. It might return false, even though they actually nest properly, since the info.
582 // has not been computed yet.
583 bool guaranteed_monitor_matching() const { return monitor_matching(); }
584 void set_guaranteed_monitor_matching() { set_monitor_matching(); }
585
586 // returns true if the method is an accessor function (setter/getter).
587 bool is_accessor() const;
588
589 // returns true if the method is a getter
590 bool is_getter() const;
591
592 // returns true if the method is a setter
593 bool is_setter() const;
594
595 // returns true if the method does nothing but return a constant of primitive type
596 bool is_constant_getter() const;
597
598 // returns true if the method name is <clinit> and the method has
599 // valid static initializer flags.
600 bool is_class_initializer() const;
601
602 // returns true if the method name is <init>
603 bool is_object_constructor() const;
604
605 // returns true if the method name is wait0
606 bool is_object_wait0() const;
607
608 // compiled code support
609 // NOTE: code() is inherently racy as deopt can be clearing code
610 // simultaneously. Use with caution.
611 bool has_compiled_code() const;
612
613 bool needs_clinit_barrier() const;
614
615 // sizing
616 static int header_size() {
617 return align_up((int)sizeof(Method), wordSize) / wordSize;
618 }
619 static int size(bool is_native);
620 int size() const { return method_size(); }
621 void log_touched(Thread* current);
622 static void print_touched_methods(outputStream* out);
623
624 // interpreter support
625 static ByteSize const_offset() { return byte_offset_of(Method, _constMethod ); }
626 static ByteSize access_flags_offset() { return byte_offset_of(Method, _access_flags ); }
627 static ByteSize from_compiled_offset() { return byte_offset_of(Method, _from_compiled_entry); }
628 static ByteSize from_compiled_inline_offset() { return byte_offset_of(Method, _from_compiled_inline_entry); }
629 static ByteSize from_compiled_inline_ro_offset(){ return byte_offset_of(Method, _from_compiled_inline_ro_entry); }
630 static ByteSize code_offset() { return byte_offset_of(Method, _code); }
631 static ByteSize flags_offset() { return byte_offset_of(Method, _flags); }
632
633 static ByteSize method_counters_offset() {
634 return byte_offset_of(Method, _method_counters);
635 }
636 #ifndef PRODUCT
637 static ByteSize compiled_invocation_counter_offset() { return byte_offset_of(Method, _compiled_invocation_count); }
638 #endif // not PRODUCT
639 static ByteSize native_function_offset() { return in_ByteSize(sizeof(Method)); }
640 static ByteSize from_interpreted_offset() { return byte_offset_of(Method, _from_interpreted_entry ); }
641 static ByteSize interpreter_entry_offset() { return byte_offset_of(Method, _i2i_entry ); }
642 static ByteSize signature_handler_offset() { return in_ByteSize(sizeof(Method) + wordSize); }
643 static ByteSize itable_index_offset() { return byte_offset_of(Method, _vtable_index ); }
644
645 // for code generation
646 static ByteSize method_data_offset() { return byte_offset_of(Method, _method_data); }
647 static ByteSize intrinsic_id_offset() { return byte_offset_of(Method, _intrinsic_id); }
648 static int intrinsic_id_size_in_bytes() { return sizeof(u2); }
649
650 // Static methods that are used to implement member methods where an exposed this pointer
651 // is needed due to possible GCs
652 static objArrayHandle resolved_checked_exceptions_impl(Method* method, TRAPS);
653
654 // Returns the byte code index from the byte code pointer
655 int bci_from(address bcp) const;
656 address bcp_from(int bci) const;
657 address bcp_from(address bcp) const;
658 int validate_bci_from_bcp(address bcp) const;
659 int validate_bci(int bci) const;
660
661 // Returns the line number for a bci if debugging information for the method is prowided,
662 // -1 is returned otherwise.
663 int line_number_from_bci(int bci) const;
664
665 // Reflection support
666 bool is_overridden_in(Klass* k) const;
667
668 // Stack walking support
669 bool is_ignored_by_security_stack_walk() const;
670
671 // JSR 292 support
672 bool is_method_handle_intrinsic() const; // MethodHandles::is_signature_polymorphic_intrinsic(intrinsic_id)
673 bool is_compiled_lambda_form() const; // intrinsic_id() == vmIntrinsics::_compiledLambdaForm
674 bool has_member_arg() const; // intrinsic_id() == vmIntrinsics::_linkToSpecial, etc.
675 static methodHandle make_method_handle_intrinsic(vmIntrinsicID iid, // _invokeBasic, _linkToVirtual
676 Symbol* signature, //anything at all
677 TRAPS);
678 // Some special methods don't need to be findable by nmethod iterators and are permanent.
679 bool can_be_allocated_in_NonNMethod_space() const { return is_method_handle_intrinsic(); }
680
681 // Continuation
682 inline bool is_continuation_enter_intrinsic() const;
683 inline bool is_continuation_yield_intrinsic() const;
684 inline bool is_continuation_native_intrinsic() const;
685 inline bool is_special_native_intrinsic() const;
686
687 static Klass* check_non_bcp_klass(Klass* klass);
688
689 enum {
690 // How many extra stack entries for invokedynamic
691 extra_stack_entries_for_jsr292 = 1
692 };
693
694 // this operates only on invoke methods:
695 // presize interpreter frames for extra interpreter stack entries, if needed
696 // Account for the extra appendix argument for invokehandle/invokedynamic
697 static int extra_stack_entries() { return extra_stack_entries_for_jsr292; }
698 static int extra_stack_words(); // = extra_stack_entries() * Interpreter::stackElementSize
699
700 // RedefineClasses() support:
701 bool on_stack() const { return on_stack_flag(); }
702 void set_on_stack(const bool value);
703
704 void record_gc_epoch();
705
706 // see the definition in Method*.cpp for the gory details
707 bool should_not_be_cached() const;
708
709 // Rewriting support
710 static methodHandle clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
711 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS);
712
713 // jmethodID handling
714 // Because the useful life-span of a jmethodID cannot be determined,
715 // once created they are never reclaimed. The methods to which they refer,
716 // however, can be GC'ed away if the class is unloaded or if the method is
717 // made obsolete or deleted -- in these cases, the jmethodID
718 // refers to null (as is the case for any weak reference).
719 static jmethodID make_jmethod_id(ClassLoaderData* cld, Method* mh);
720
721 // Use resolve_jmethod_id() in situations where the caller is expected
722 // to provide a valid jmethodID; the only sanity checks are in asserts;
723 // result guaranteed not to be null.
724 static Method* resolve_jmethod_id(jmethodID mid);
725
726 // Use checked_resolve_jmethod_id() in situations where the caller
727 // should provide a valid jmethodID, but might not. Null is returned
728 // when the jmethodID does not refer to a valid method.
729 static Method* checked_resolve_jmethod_id(jmethodID mid);
730
731 static void change_method_associated_with_jmethod_id(jmethodID old_jmid_ptr, Method* new_method);
732 static bool validate_jmethod_id(jmethodID mid);
733
734 // Clear jmethodID
735 void clear_jmethod_id();
736 static void print_jmethod_ids_count(const ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
737
738 // Get this method's jmethodID -- allocate if it doesn't exist
739 jmethodID jmethod_id();
740
741 // Lookup the jmethodID for this method. Return null if not found.
742 // NOTE that this function can be called from a signal handler
743 // (see AsyncGetCallTrace support for Forte Analyzer) and this
744 // needs to be async-safe. No allocation should be done and
745 // so handles are not used to avoid deadlock.
746 jmethodID find_jmethod_id_or_null() { return method_holder()->jmethod_id_or_null(this); }
747
748 // Support for inlining of intrinsic methods
749 vmIntrinsicID intrinsic_id() const { return (vmIntrinsicID) _intrinsic_id; }
750 void set_intrinsic_id(vmIntrinsicID id) { _intrinsic_id = (u2) id; }
751
752 // Helper routines for intrinsic_id() and vmIntrinsics::method().
753 void init_intrinsic_id(vmSymbolID klass_id); // updates from _none if a match
754 static vmSymbolID klass_id_for_intrinsics(const Klass* holder);
755
756 bool caller_sensitive() const { return constMethod()->caller_sensitive(); }
757 void set_caller_sensitive() { constMethod()->set_caller_sensitive(); }
758
759 bool changes_current_thread() const { return constMethod()->changes_current_thread(); }
760 void set_changes_current_thread() { constMethod()->set_changes_current_thread(); }
761
762 bool jvmti_hide_events() const { return constMethod()->jvmti_hide_events(); }
763 void set_jvmti_hide_events() { constMethod()->set_jvmti_hide_events(); }
764
765 bool jvmti_mount_transition() const { return constMethod()->jvmti_mount_transition(); }
766 void set_jvmti_mount_transition() { constMethod()->set_jvmti_mount_transition(); }
767
768 bool is_hidden() const { return constMethod()->is_hidden(); }
769 void set_is_hidden() { constMethod()->set_is_hidden(); }
770
771 bool is_scoped() const { return constMethod()->is_scoped(); }
772 void set_scoped() { constMethod()->set_is_scoped(); }
773
774 bool intrinsic_candidate() const { return constMethod()->intrinsic_candidate(); }
775 void set_intrinsic_candidate() { constMethod()->set_intrinsic_candidate(); }
776
777 bool has_injected_profile() const { return constMethod()->has_injected_profile(); }
778 void set_has_injected_profile() { constMethod()->set_has_injected_profile(); }
779
780 bool has_reserved_stack_access() const { return constMethod()->reserved_stack_access(); }
781 void set_has_reserved_stack_access() { constMethod()->set_reserved_stack_access(); }
782
783 bool is_scalarized_arg(int idx) const;
784 bool is_scalarized_buffer_arg(int idx) const;
785
786 bool c1_needs_stack_repair() const { return constMethod()->c1_needs_stack_repair(); }
787 void set_c1_needs_stack_repair() { constMethod()->set_c1_needs_stack_repair(); }
788
789 bool c2_needs_stack_repair() const { return constMethod()->c2_needs_stack_repair(); }
790 void set_c2_needs_stack_repair() { constMethod()->set_c2_needs_stack_repair(); }
791
792 bool mismatch() const { return constMethod()->mismatch(); }
793 void set_mismatch() { constMethod()->set_mismatch(); }
794
795 JFR_ONLY(DEFINE_TRACE_FLAG_ACCESSOR;)
796
797 ConstMethod::MethodType method_type() const {
798 return _constMethod->method_type();
799 }
800 bool is_overpass() const { return method_type() == ConstMethod::OVERPASS; }
801
802 // On-stack replacement support
803 bool has_osr_nmethod(int level, bool match_level) {
804 return method_holder()->lookup_osr_nmethod(this, InvocationEntryBci, level, match_level) != nullptr;
805 }
806
807 nmethod* lookup_osr_nmethod_for(int bci, int level, bool match_level) {
808 return method_holder()->lookup_osr_nmethod(this, bci, level, match_level);
809 }
810
811 // Find if klass for method is loaded
812 bool is_klass_loaded_by_klass_index(int klass_index) const;
813 bool is_klass_loaded(int refinfo_index, Bytecodes::Code bc, bool must_be_resolved = false) const;
814
815 // Indicates whether compilation failed earlier for this method, or
816 // whether it is not compilable for another reason like having a
817 // breakpoint set in it.
818 bool is_not_compilable(int comp_level = CompLevel_any) const;
819 void set_not_compilable(const char* reason, int comp_level = CompLevel_all, bool report = true);
820 void set_not_compilable_quietly(const char* reason, int comp_level = CompLevel_all) {
821 set_not_compilable(reason, comp_level, false);
822 }
823 bool is_not_osr_compilable(int comp_level = CompLevel_any) const;
824 void set_not_osr_compilable(const char* reason, int comp_level = CompLevel_all, bool report = true);
825 void set_not_osr_compilable_quietly(const char* reason, int comp_level = CompLevel_all) {
826 set_not_osr_compilable(reason, comp_level, false);
827 }
828 bool is_always_compilable() const;
829
830 private:
831 void print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason);
832
833 public:
834 MethodCounters* get_method_counters(Thread* current) {
835 if (_method_counters == nullptr) {
836 build_method_counters(current, this);
837 }
838 return _method_counters;
839 }
840
841 void clear_is_not_c1_compilable() { set_is_not_c1_compilable(false); }
842 void clear_is_not_c2_compilable() { set_is_not_c2_compilable(false); }
843 void clear_is_not_c2_osr_compilable() { set_is_not_c2_osr_compilable(false); }
844
845 // not_c1_osr_compilable == not_c1_compilable
846 bool is_not_c1_osr_compilable() const { return is_not_c1_compilable(); }
847 void set_is_not_c1_osr_compilable() { set_is_not_c1_compilable(); }
848 void clear_is_not_c1_osr_compilable() { clear_is_not_c1_compilable(); }
849
850 // Background compilation support
851 void clear_queued_for_compilation() { set_queued_for_compilation(false); }
852
853 // Resolve all classes in signature, return 'true' if successful
854 static bool load_signature_classes(const methodHandle& m, TRAPS);
855
856 // Printing
857 void print_short_name(outputStream* st = tty) const; // prints as klassname::methodname; Exposed so field engineers can debug VM
858 #if INCLUDE_JVMTI
859 void print_name(outputStream* st = tty) const; // prints as "virtual void foo(int)"; exposed for -Xlog:redefine+class
860 #else
861 void print_name(outputStream* st = tty) const PRODUCT_RETURN; // prints as "virtual void foo(int)"
862 #endif
863
864 typedef int (*method_comparator_func)(Method* a, Method* b);
865
866 // Helper routine used for method sorting
867 static void sort_methods(Array<Method*>* methods, bool set_idnums = true, method_comparator_func func = nullptr);
868
869 // Deallocation function for redefine classes or if an error occurs
870 void deallocate_contents(ClassLoaderData* loader_data);
871
872 void release_C_heap_structures();
873
874 Method* get_new_method() const {
875 InstanceKlass* holder = method_holder();
876 Method* new_method = holder->method_with_idnum(orig_method_idnum());
877
878 assert(new_method != nullptr, "method_with_idnum() should not be null");
879 assert(this != new_method, "sanity check");
880 return new_method;
881 }
882
883 // Printing
884 #ifndef PRODUCT
885 void print_on(outputStream* st) const;
886 #endif
887 void print_value_on(outputStream* st) const;
888 void print_access_flags(outputStream* st) const;
889 void print_linkage_flags(outputStream* st) const PRODUCT_RETURN;
890
891 const char* internal_name() const { return "{method}"; }
892
893 // Check for valid method pointer
894 static bool has_method_vptr(const void* ptr);
895 static bool is_valid_method(const Method* m);
896
897 // Verify
898 void verify() { verify_on(tty); }
899 void verify_on(outputStream* st);
900
901 private:
902
903 // Inlined elements
904 address* native_function_addr() const { assert(is_native(), "must be native"); return (address*) (this+1); }
905 address* signature_handler_addr() const { return native_function_addr() + 1; }
906 };
907
908
909 // Utility class for compressing line number tables
910
911 class CompressedLineNumberWriteStream: public CompressedWriteStream {
912 private:
913 int _bci;
914 int _line;
915 public:
916 // Constructor
917 CompressedLineNumberWriteStream(int initial_size) : CompressedWriteStream(initial_size), _bci(0), _line(0) {}
918 CompressedLineNumberWriteStream(u_char* buffer, int initial_size) : CompressedWriteStream(buffer, initial_size), _bci(0), _line(0) {}
919
920 // Write (bci, line number) pair to stream
921 void write_pair_regular(int bci_delta, int line_delta);
922
923 // If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
924 // we save it as one byte, otherwise we write a 0xFF escape character
925 // and use regular compression. 0x0 is used as end-of-stream terminator.
926 void write_pair_inline(int bci, int line);
927
928 void write_pair(int bci, int line);
929
930 // Write end-of-stream marker
931 void write_terminator() { write_byte(0); }
932 };
933
934
935 // Utility class for decompressing line number tables
936
937 class CompressedLineNumberReadStream: public CompressedReadStream {
938 private:
939 int _bci;
940 int _line;
941 public:
942 // Constructor
943 CompressedLineNumberReadStream(u_char* buffer);
944 // Read (bci, line number) pair from stream. Returns false at end-of-stream.
945 bool read_pair();
946 // Accessing bci and line number (after calling read_pair)
947 int bci() const { return _bci; }
948 int line() const { return _line; }
949 };
950
951
952 #if INCLUDE_JVMTI
953
954 /// Fast Breakpoints.
955
956 // If this structure gets more complicated (because bpts get numerous),
957 // move it into its own header.
958
959 // There is presently no provision for concurrent access
960 // to breakpoint lists, which is only OK for JVMTI because
961 // breakpoints are written only at safepoints, and are read
962 // concurrently only outside of safepoints.
963
964 class BreakpointInfo : public CHeapObj<mtClass> {
965 friend class VMStructs;
966 private:
967 Bytecodes::Code _orig_bytecode;
968 int _bci;
969 u2 _name_index; // of method
970 u2 _signature_index; // of method
971 BreakpointInfo* _next; // simple storage allocation
972
973 public:
974 BreakpointInfo(Method* m, int bci);
975
976 // accessors
977 Bytecodes::Code orig_bytecode() { return _orig_bytecode; }
978 void set_orig_bytecode(Bytecodes::Code code) { _orig_bytecode = code; }
979 int bci() { return _bci; }
980
981 BreakpointInfo* next() const { return _next; }
982 void set_next(BreakpointInfo* n) { _next = n; }
983
984 // helps for searchers
985 bool match(const Method* m, int bci) {
986 return bci == _bci && match(m);
987 }
988
989 bool match(const Method* m) {
990 return _name_index == m->name_index() &&
991 _signature_index == m->signature_index();
992 }
993
994 void set(Method* method);
995 void clear(Method* method);
996 };
997
998 #endif // INCLUDE_JVMTI
999
1000 // Utility class for access exception handlers
1001 class ExceptionTable : public StackObj {
1002 private:
1003 ExceptionTableElement* _table;
1004 u2 _length;
1005
1006 public:
1007 ExceptionTable(const Method* m) {
1008 if (m->has_exception_handler()) {
1009 _table = m->exception_table_start();
1010 _length = m->exception_table_length();
1011 } else {
1012 _table = nullptr;
1013 _length = 0;
1014 }
1015 }
1016
1017 u2 length() const {
1018 return _length;
1019 }
1020
1021 u2 start_pc(int idx) const {
1022 assert(idx < _length, "out of bounds");
1023 return _table[idx].start_pc;
1024 }
1025
1026 void set_start_pc(int idx, u2 value) {
1027 assert(idx < _length, "out of bounds");
1028 _table[idx].start_pc = value;
1029 }
1030
1031 u2 end_pc(int idx) const {
1032 assert(idx < _length, "out of bounds");
1033 return _table[idx].end_pc;
1034 }
1035
1036 void set_end_pc(int idx, u2 value) {
1037 assert(idx < _length, "out of bounds");
1038 _table[idx].end_pc = value;
1039 }
1040
1041 u2 handler_pc(int idx) const {
1042 assert(idx < _length, "out of bounds");
1043 return _table[idx].handler_pc;
1044 }
1045
1046 void set_handler_pc(int idx, u2 value) {
1047 assert(idx < _length, "out of bounds");
1048 _table[idx].handler_pc = value;
1049 }
1050
1051 u2 catch_type_index(int idx) const {
1052 assert(idx < _length, "out of bounds");
1053 return _table[idx].catch_type_index;
1054 }
1055
1056 void set_catch_type_index(int idx, u2 value) {
1057 assert(idx < _length, "out of bounds");
1058 _table[idx].catch_type_index = value;
1059 }
1060 };
1061
1062 #endif // SHARE_OOPS_METHOD_HPP