1 /*
2 * Copyright (c) 1997, 2023, 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 "interpreter/invocationCounter.hpp"
31 #include "oops/annotations.hpp"
32 #include "oops/constantPool.hpp"
33 #include "oops/methodCounters.hpp"
34 #include "oops/methodFlags.hpp"
35 #include "oops/instanceKlass.hpp"
36 #include "oops/oop.hpp"
37 #include "oops/typeArrayOop.hpp"
38 #include "utilities/accessFlags.hpp"
39 #include "utilities/align.hpp"
40 #include "utilities/growableArray.hpp"
41 #include "utilities/macros.hpp"
42 #include "utilities/vmEnums.hpp"
43 #if INCLUDE_JFR
44 #include "jfr/support/jfrTraceIdExtension.hpp"
45 #endif
46
47
48 // A Method represents a Java method.
49 //
50 // Note that most applications load thousands of methods, so keeping the size of this
51 // class small has a big impact on footprint.
52 //
53 // Note that native_function and signature_handler have to be at fixed offsets
54 // (required by the interpreter)
55 //
56 // Method embedded field layout (after declared fields):
57 // [EMBEDDED native_function (present only if native) ]
58 // [EMBEDDED signature_handler (present only if native) ]
59
60 class CheckedExceptionElement;
61 class LocalVariableTableElement;
62 class AdapterHandlerEntry;
63 class MethodData;
64 class MethodCounters;
65 class ConstMethod;
66 class InlineTableSizes;
67 class CompiledMethod;
68 class InterpreterOopMap;
69
70 class Method : public Metadata {
71 friend class VMStructs;
72 friend class JVMCIVMStructs;
73 friend class MethodTest;
74 private:
75 // If you add a new field that points to any metaspace object, you
76 // must add this field to Method::metaspace_pointers_do().
77 ConstMethod* _constMethod; // Method read-only data.
78 MethodData* _method_data;
79 MethodCounters* _method_counters;
80 AdapterHandlerEntry* _adapter;
81 AccessFlags _access_flags; // Access flags
82 int _vtable_index; // vtable index of this method (see VtableIndexFlag)
83 MethodFlags _flags;
84
85 u2 _intrinsic_id; // vmSymbols::intrinsic_id (0 == _none)
86
87 JFR_ONLY(DEFINE_TRACE_FLAG;)
88
89 #ifndef PRODUCT
90 int64_t _compiled_invocation_count;
91
92 Symbol* _name;
93 #endif
94 // Entry point for calling both from and to the interpreter.
95 address _i2i_entry; // All-args-on-stack calling convention
96 // Entry point for calling from compiled code, to compiled code if it exists
97 // or else the interpreter.
98 volatile address _from_compiled_entry; // Cache of: _code ? _code->verified_entry_point() : _adapter->c2i_entry()
99 volatile address _from_compiled_inline_ro_entry; // Cache of: _code ? _code->verified_inline_ro_entry_point() : _adapter->c2i_inline_ro_entry()
100 volatile address _from_compiled_inline_entry; // Cache of: _code ? _code->verified_inline_entry_point() : _adapter->c2i_inline_entry()
101 // The entry point for calling both from and to compiled code is
102 // "_code->entry_point()". Because of tiered compilation and de-opt, this
103 // field can come and go. It can transition from null to not-null at any
104 // time (whenever a compile completes). It can transition from not-null to
105 // null only at safepoints (because of a de-opt).
106 CompiledMethod* volatile _code; // Points to the corresponding piece of native code
107 volatile address _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry
108
109 // Constructor
110 Method(ConstMethod* xconst, AccessFlags access_flags, Symbol* name);
111 public:
112
113 static Method* allocate(ClassLoaderData* loader_data,
114 int byte_code_size,
115 AccessFlags access_flags,
116 InlineTableSizes* sizes,
117 ConstMethod::MethodType method_type,
118 Symbol* name,
119 TRAPS);
120
121 // CDS and vtbl checking can create an empty Method to get vtbl pointer.
122 Method(){}
123
124 virtual bool is_method() const { return true; }
125
126 #if INCLUDE_CDS
127 void remove_unshareable_info();
128 void restore_unshareable_info(TRAPS);
129 #endif
130
131 // accessors for instance variables
132
133 ConstMethod* constMethod() const { return _constMethod; }
134 void set_constMethod(ConstMethod* xconst) { _constMethod = xconst; }
135
136
137 static address make_adapters(const methodHandle& mh, TRAPS);
138 address from_compiled_entry() const;
139 address from_compiled_inline_ro_entry() const;
140 address from_compiled_inline_entry() const;
141 address from_interpreted_entry() const;
142
143 // access flag
144 AccessFlags access_flags() const { return _access_flags; }
145 void set_access_flags(AccessFlags flags) { _access_flags = flags; }
146
147 // name
148 Symbol* name() const { return constants()->symbol_at(name_index()); }
149 u2 name_index() const { return constMethod()->name_index(); }
150 void set_name_index(int index) { constMethod()->set_name_index(index); }
151
152 // signature
153 Symbol* signature() const { return constants()->symbol_at(signature_index()); }
154 u2 signature_index() const { return constMethod()->signature_index(); }
155 void set_signature_index(int index) { constMethod()->set_signature_index(index); }
156
157 // generics support
158 Symbol* generic_signature() const { int idx = generic_signature_index(); return ((idx != 0) ? constants()->symbol_at(idx) : nullptr); }
159 u2 generic_signature_index() const { return constMethod()->generic_signature_index(); }
160
161 // annotations support
162 AnnotationArray* annotations() const {
163 return constMethod()->method_annotations();
164 }
165 AnnotationArray* parameter_annotations() const {
166 return constMethod()->parameter_annotations();
167 }
168 AnnotationArray* annotation_default() const {
169 return constMethod()->default_annotations();
170 }
171 AnnotationArray* type_annotations() const {
172 return constMethod()->type_annotations();
173 }
174
175 // Helper routine: get klass name + "." + method name + signature as
176 // C string, for the purpose of providing more useful
177 // fatal error handling. The string is allocated in resource
178 // area if a buffer is not provided by the caller.
179 char* name_and_sig_as_C_string() const;
180 char* name_and_sig_as_C_string(char* buf, int size) const;
181
182 // Static routine in the situations we don't have a Method*
183 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature);
184 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);
185
186 // Get return type + klass name + "." + method name + ( parameters types )
187 // as a C string or print it to an outputStream.
188 // This is to be used to assemble strings passed to Java, so that
189 // the text more resembles Java code. Used in exception messages.
190 // Memory is allocated in the resource area; the caller needs
191 // a ResourceMark.
192 const char* external_name() const;
193 void print_external_name(outputStream *os) const;
194
195 static const char* external_name( Klass* klass, Symbol* method_name, Symbol* signature);
196 static void print_external_name(outputStream *os, Klass* klass, Symbol* method_name, Symbol* signature);
197
198 Bytecodes::Code java_code_at(int bci) const {
199 return Bytecodes::java_code_at(this, bcp_from(bci));
200 }
201 Bytecodes::Code code_at(int bci) const {
202 return Bytecodes::code_at(this, bcp_from(bci));
203 }
204
205 // JVMTI breakpoints
206 #if !INCLUDE_JVMTI
207 Bytecodes::Code orig_bytecode_at(int bci) const {
208 ShouldNotReachHere();
209 return Bytecodes::_shouldnotreachhere;
210 }
211 void set_orig_bytecode_at(int bci, Bytecodes::Code code) {
212 ShouldNotReachHere();
213 };
214 u2 number_of_breakpoints() const {return 0;}
215 #else // !INCLUDE_JVMTI
216 Bytecodes::Code orig_bytecode_at(int bci) const;
217 void set_orig_bytecode_at(int bci, Bytecodes::Code code);
218 void set_breakpoint(int bci);
219 void clear_breakpoint(int bci);
220 void clear_all_breakpoints();
221 // Tracking number of breakpoints, for fullspeed debugging.
222 // Only mutated by VM thread.
223 u2 number_of_breakpoints() const {
224 MethodCounters* mcs = method_counters();
225 if (mcs == nullptr) {
226 return 0;
227 } else {
228 return mcs->number_of_breakpoints();
229 }
230 }
231 void incr_number_of_breakpoints(Thread* current) {
232 MethodCounters* mcs = get_method_counters(current);
233 if (mcs != nullptr) {
234 mcs->incr_number_of_breakpoints();
235 }
236 }
237 void decr_number_of_breakpoints(Thread* current) {
238 MethodCounters* mcs = get_method_counters(current);
239 if (mcs != nullptr) {
240 mcs->decr_number_of_breakpoints();
241 }
242 }
243 // Initialization only
244 void clear_number_of_breakpoints() {
245 MethodCounters* mcs = method_counters();
246 if (mcs != nullptr) {
247 mcs->clear_number_of_breakpoints();
248 }
249 }
250 #endif // !INCLUDE_JVMTI
251
252 // index into InstanceKlass methods() array
253 // note: also used by jfr
254 u2 method_idnum() const { return constMethod()->method_idnum(); }
255 void set_method_idnum(u2 idnum) { constMethod()->set_method_idnum(idnum); }
256
257 u2 orig_method_idnum() const { return constMethod()->orig_method_idnum(); }
258 void set_orig_method_idnum(u2 idnum) { constMethod()->set_orig_method_idnum(idnum); }
259
260 // code size
261 u2 code_size() const { return constMethod()->code_size(); }
262
263 // method size in words
264 int method_size() const { return sizeof(Method)/wordSize + ( is_native() ? 2 : 0 ); }
265
266 // constant pool for Klass* holding this method
267 ConstantPool* constants() const { return constMethod()->constants(); }
268 void set_constants(ConstantPool* c) { constMethod()->set_constants(c); }
269
270 // max stack
271 // return original max stack size for method verification
272 u2 verifier_max_stack() const { return constMethod()->max_stack(); }
273 int max_stack() const { return constMethod()->max_stack() + extra_stack_entries(); }
274 void set_max_stack(int size) { constMethod()->set_max_stack(size); }
275
276 // max locals
277 u2 max_locals() const { return constMethod()->max_locals(); }
278 void set_max_locals(int size) { constMethod()->set_max_locals(size); }
279
280 int highest_comp_level() const;
281 void set_highest_comp_level(int level);
282 int highest_osr_comp_level() const;
283 void set_highest_osr_comp_level(int level);
284
285 #if COMPILER2_OR_JVMCI
286 // Count of times method was exited via exception while interpreting
287 void interpreter_throwout_increment(Thread* current) {
288 MethodCounters* mcs = get_method_counters(current);
289 if (mcs != nullptr) {
290 mcs->interpreter_throwout_increment();
291 }
292 }
293 #endif
294
295 int interpreter_throwout_count() const {
296 MethodCounters* mcs = method_counters();
297 if (mcs == nullptr) {
298 return 0;
299 } else {
300 return mcs->interpreter_throwout_count();
301 }
302 }
303
304 u2 size_of_parameters() const { return constMethod()->size_of_parameters(); }
305
306 bool has_stackmap_table() const {
307 return constMethod()->has_stackmap_table();
308 }
309
310 Array<u1>* stackmap_data() const {
311 return constMethod()->stackmap_data();
312 }
313
314 void set_stackmap_data(Array<u1>* sd) {
315 constMethod()->set_stackmap_data(sd);
316 }
317
318 // exception handler table
319 bool has_exception_handler() const
320 { return constMethod()->has_exception_table(); }
321 u2 exception_table_length() const
322 { return constMethod()->exception_table_length(); }
323 ExceptionTableElement* exception_table_start() const
324 { return constMethod()->exception_table_start(); }
325
326 // Finds the first entry point bci of an exception handler for an
327 // exception of klass ex_klass thrown at throw_bci. A value of null
328 // for ex_klass indicates that the exception klass is not known; in
329 // this case it matches any constraint class. Returns -1 if the
330 // exception cannot be handled in this method. The handler
331 // constraint classes are loaded if necessary. Note that this may
332 // throw an exception if loading of the constraint classes causes
333 // an IllegalAccessError (bugid 4307310) or an OutOfMemoryError.
334 // If an exception is thrown, returns the bci of the
335 // exception handler which caused the exception to be thrown, which
336 // is needed for proper retries. See, for example,
337 // InterpreterRuntime::exception_handler_for_exception.
338 static int fast_exception_handler_bci_for(const methodHandle& mh, Klass* ex_klass, int throw_bci, TRAPS);
339
340 static bool register_native(Klass* k,
341 Symbol* name,
342 Symbol* signature,
343 address entry,
344 TRAPS);
345
346 // method data access
347 MethodData* method_data() const {
348 return _method_data;
349 }
350
351 void set_method_data(MethodData* data);
352
353 MethodCounters* method_counters() const {
354 return _method_counters;
355 }
356
357 void clear_method_counters() {
358 _method_counters = nullptr;
359 }
360
361 bool init_method_counters(MethodCounters* counters);
362
363 int prev_event_count() const {
364 MethodCounters* mcs = method_counters();
365 return mcs == nullptr ? 0 : mcs->prev_event_count();
366 }
367 void set_prev_event_count(int count) {
368 MethodCounters* mcs = method_counters();
369 if (mcs != nullptr) {
370 mcs->set_prev_event_count(count);
371 }
372 }
373 jlong prev_time() const {
374 MethodCounters* mcs = method_counters();
375 return mcs == nullptr ? 0 : mcs->prev_time();
376 }
377 void set_prev_time(jlong time) {
378 MethodCounters* mcs = method_counters();
379 if (mcs != nullptr) {
380 mcs->set_prev_time(time);
381 }
382 }
383 float rate() const {
384 MethodCounters* mcs = method_counters();
385 return mcs == nullptr ? 0 : mcs->rate();
386 }
387 void set_rate(float rate) {
388 MethodCounters* mcs = method_counters();
389 if (mcs != nullptr) {
390 mcs->set_rate(rate);
391 }
392 }
393
394 int invocation_count() const;
395 int backedge_count() const;
396
397 bool was_executed_more_than(int n);
398 bool was_never_executed() { return !was_executed_more_than(0); }
399
400 static void build_profiling_method_data(const methodHandle& method, TRAPS);
401
402 static MethodCounters* build_method_counters(Thread* current, Method* m);
403
404 int interpreter_invocation_count() { return invocation_count(); }
405
406 #ifndef PRODUCT
407 int64_t compiled_invocation_count() const { return _compiled_invocation_count;}
408 void set_compiled_invocation_count(int count) { _compiled_invocation_count = (int64_t)count; }
409 #else
410 // for PrintMethodData in a product build
411 int64_t compiled_invocation_count() const { return 0; }
412 #endif // not PRODUCT
413
414 // nmethod/verified compiler entry
415 address verified_code_entry();
416 address verified_inline_code_entry();
417 address verified_inline_ro_code_entry();
418 bool check_code() const; // Not inline to avoid circular ref
419 CompiledMethod* code() const;
420
421 // Locks CompiledMethod_lock if not held.
422 void unlink_code(CompiledMethod *compare);
423 // Locks CompiledMethod_lock if not held.
424 void unlink_code();
425
426 private:
427 // Either called with CompiledMethod_lock held or from constructor.
428 void clear_code();
429
430 public:
431 static void set_code(const methodHandle& mh, CompiledMethod* code);
432 void set_adapter_entry(AdapterHandlerEntry* adapter) {
433 _adapter = adapter;
434 }
435 void set_from_compiled_entry(address entry) {
436 _from_compiled_entry = entry;
437 }
438 void set_from_compiled_inline_ro_entry(address entry) {
439 _from_compiled_inline_ro_entry = entry;
440 }
441 void set_from_compiled_inline_entry(address entry) {
442 _from_compiled_inline_entry = entry;
443 }
444
445 address get_i2c_entry();
446 address get_c2i_entry();
447 address get_c2i_inline_entry();
448 address get_c2i_unverified_entry();
449 address get_c2i_unverified_inline_entry();
450 address get_c2i_no_clinit_check_entry();
451 AdapterHandlerEntry* adapter() const {
452 return _adapter;
453 }
454 // setup entry points
455 void link_method(const methodHandle& method, TRAPS);
456 // clear entry points. Used by sharing code during dump time
457 void unlink_method() NOT_CDS_RETURN;
458 void remove_unshareable_flags() NOT_CDS_RETURN;
459
460 // the number of argument reg slots that the compiled method uses on the stack.
461 int num_stack_arg_slots() const { return constMethod()->num_stack_arg_slots(); }
462
463 virtual void metaspace_pointers_do(MetaspaceClosure* iter);
464 virtual MetaspaceObj::Type type() const { return MethodType; }
465
466 // vtable index
467 enum VtableIndexFlag {
468 // Valid vtable indexes are non-negative (>= 0).
469 // These few negative values are used as sentinels.
470 itable_index_max = -10, // first itable index, growing downward
471 pending_itable_index = -9, // itable index will be assigned
472 invalid_vtable_index = -4, // distinct from any valid vtable index
473 garbage_vtable_index = -3, // not yet linked; no vtable layout yet
474 nonvirtual_vtable_index = -2 // there is no need for vtable dispatch
475 // 6330203 Note: Do not use -1, which was overloaded with many meanings.
476 };
477 DEBUG_ONLY(bool valid_vtable_index() const { return _vtable_index >= nonvirtual_vtable_index; })
478 bool has_vtable_index() const { return _vtable_index >= 0; }
479 int vtable_index() const { return _vtable_index; }
480 void set_vtable_index(int index);
481 DEBUG_ONLY(bool valid_itable_index() const { return _vtable_index <= pending_itable_index; })
482 bool has_itable_index() const { return _vtable_index <= itable_index_max; }
483 int itable_index() const { assert(valid_itable_index(), "");
484 return itable_index_max - _vtable_index; }
485 void set_itable_index(int index);
486
487 // interpreter entry
488 address interpreter_entry() const { return _i2i_entry; }
489 // Only used when first initialize so we can set _i2i_entry and _from_interpreted_entry
490 void set_interpreter_entry(address entry) {
491 if (_i2i_entry != entry) {
492 _i2i_entry = entry;
493 }
494 if (_from_interpreted_entry != entry) {
495 _from_interpreted_entry = entry;
496 }
497 }
498
499 // native function (used for native methods only)
500 enum {
501 native_bind_event_is_interesting = true
502 };
503 address native_function() const { return *(native_function_addr()); }
504
505 // Must specify a real function (not null).
506 // Use clear_native_function() to unregister.
507 void set_native_function(address function, bool post_event_flag);
508 bool has_native_function() const;
509 void clear_native_function();
510
511 // signature handler (used for native methods only)
512 address signature_handler() const { return *(signature_handler_addr()); }
513 void set_signature_handler(address handler);
514
515 // Interpreter oopmap support
516 void mask_for(int bci, InterpreterOopMap* mask);
517
518 // operations on invocation counter
519 void print_invocation_count();
520
521 // byte codes
522 void set_code(address code) { return constMethod()->set_code(code); }
523 address code_base() const { return constMethod()->code_base(); }
524 bool contains(address bcp) const { return constMethod()->contains(bcp); }
525
526 // prints byte codes
527 void print_codes(int flags = 0) const { print_codes_on(tty, flags); }
528 void print_codes_on(outputStream* st, int flags = 0) const;
529 void print_codes_on(int from, int to, outputStream* st, int flags = 0) const;
530
531 // method parameters
532 bool has_method_parameters() const
533 { return constMethod()->has_method_parameters(); }
534 int method_parameters_length() const
535 { return constMethod()->method_parameters_length(); }
536 MethodParametersElement* method_parameters_start() const
537 { return constMethod()->method_parameters_start(); }
538
539 // checked exceptions
540 u2 checked_exceptions_length() const
541 { return constMethod()->checked_exceptions_length(); }
542 CheckedExceptionElement* checked_exceptions_start() const
543 { return constMethod()->checked_exceptions_start(); }
544
545 // localvariable table
546 bool has_localvariable_table() const
547 { return constMethod()->has_localvariable_table(); }
548 u2 localvariable_table_length() const
549 { return constMethod()->localvariable_table_length(); }
550 LocalVariableTableElement* localvariable_table_start() const
551 { return constMethod()->localvariable_table_start(); }
552
553 bool has_linenumber_table() const
554 { return constMethod()->has_linenumber_table(); }
555 u_char* compressed_linenumber_table() const
556 { return constMethod()->compressed_linenumber_table(); }
557
558 // method holder (the Klass* holding this method)
559 InstanceKlass* method_holder() const { return constants()->pool_holder(); }
560
561 Symbol* klass_name() const; // returns the name of the method holder
562 BasicType result_type() const { return constMethod()->result_type(); }
563 bool is_returning_oop() const { BasicType r = result_type(); return is_reference_type(r); }
564 InlineKlass* returns_inline_type(Thread* thread) const;
565
566 // Checked exceptions thrown by this method (resolved to mirrors)
567 objArrayHandle resolved_checked_exceptions(TRAPS) { return resolved_checked_exceptions_impl(this, THREAD); }
568
569 // Access flags
570 bool is_public() const { return access_flags().is_public(); }
571 bool is_private() const { return access_flags().is_private(); }
572 bool is_protected() const { return access_flags().is_protected(); }
573 bool is_package_private() const { return !is_public() && !is_private() && !is_protected(); }
574 bool is_static() const { return access_flags().is_static(); }
575 bool is_final() const { return access_flags().is_final(); }
576 bool is_synchronized() const { return access_flags().is_synchronized();}
577 bool is_native() const { return access_flags().is_native(); }
578 bool is_abstract() const { return access_flags().is_abstract(); }
579 bool is_synthetic() const { return access_flags().is_synthetic(); }
580
581 // returns true if contains only return operation
582 bool is_empty_method() const;
583
584 // returns true if this is a vanilla constructor
585 bool is_vanilla_constructor() const;
586
587 // checks method and its method holder
588 bool is_final_method() const;
589 bool is_final_method(AccessFlags class_access_flags) const;
590 // interface method declared with 'default' - excludes private interface methods
591 bool is_default_method() const;
592
593 // true if method needs no dynamic dispatch (final and/or no vtable entry)
594 bool can_be_statically_bound() const;
595 bool can_be_statically_bound(InstanceKlass* context) const;
596 bool can_be_statically_bound(AccessFlags class_access_flags) const;
597
598 // true if method can omit stack trace in throw in compiled code.
599 bool can_omit_stack_trace();
600
601 // Flags getting and setting.
602 #define M_STATUS_GET_SET(name, ignore) \
603 bool name() const { return _flags.name(); } \
604 void set_##name(bool x) { _flags.set_##name(x); } \
605 void set_##name() { _flags.set_##name(true); }
606 M_STATUS_DO(M_STATUS_GET_SET)
607 #undef M_STATUS_GET_SET
608
609 // returns true if the method has any backward branches.
610 bool has_loops() {
611 return has_loops_flag_init() ? has_loops_flag() : compute_has_loops_flag();
612 };
613
614 bool compute_has_loops_flag();
615 bool set_has_loops() {
616 // set both the flags and that it's been initialized.
617 set_has_loops_flag();
618 set_has_loops_flag_init();
619 return true;
620 }
621
622 // returns true if the method has any monitors.
623 bool has_monitors() const { return is_synchronized() || has_monitor_bytecodes(); }
624
625 // monitor matching. This returns a conservative estimate of whether the monitorenter/monitorexit bytecodes
626 // properly nest in the method. It might return false, even though they actually nest properly, since the info.
627 // has not been computed yet.
628 bool guaranteed_monitor_matching() const { return monitor_matching(); }
629 void set_guaranteed_monitor_matching() { set_monitor_matching(); }
630
631 // returns true if the method is an accessor function (setter/getter).
632 bool is_accessor() const;
633
634 // returns true if the method is a getter
635 bool is_getter() const;
636
637 // returns true if the method is a setter
638 bool is_setter() const;
639
640 // returns true if the method does nothing but return a constant of primitive type
641 bool is_constant_getter() const;
642
643 // returns true if the method name is <clinit> and the method has
644 // valid static initializer flags.
645 bool is_class_initializer() const;
646
647 // returns true if the method name is <init> and the method is not a static factory
648 bool is_object_constructor() const;
649
650 // returns true if the method is an object constructor or class initializer
651 // (non-static <init> or <clinit>), but false for factories (static <vnew>).
652 bool is_object_constructor_or_class_initializer() const;
653
654 // returns true if the method name is <vnew> and the method is static
655 bool is_static_vnew_factory() const;
656
657 // compiled code support
658 // NOTE: code() is inherently racy as deopt can be clearing code
659 // simultaneously. Use with caution.
660 bool has_compiled_code() const;
661
662 bool needs_clinit_barrier() const;
663
664 // sizing
665 static int header_size() {
666 return align_up((int)sizeof(Method), wordSize) / wordSize;
667 }
668 static int size(bool is_native);
669 int size() const { return method_size(); }
670 void log_touched(Thread* current);
671 static void print_touched_methods(outputStream* out);
672
673 // interpreter support
674 static ByteSize const_offset() { return byte_offset_of(Method, _constMethod ); }
675 static ByteSize access_flags_offset() { return byte_offset_of(Method, _access_flags ); }
676 static ByteSize from_compiled_offset() { return byte_offset_of(Method, _from_compiled_entry); }
677 static ByteSize from_compiled_inline_offset() { return byte_offset_of(Method, _from_compiled_inline_entry); }
678 static ByteSize from_compiled_inline_ro_offset(){ return byte_offset_of(Method, _from_compiled_inline_ro_entry); }
679 static ByteSize code_offset() { return byte_offset_of(Method, _code); }
680 static ByteSize flags_offset() { return byte_offset_of(Method, _flags); }
681
682 static ByteSize method_counters_offset() {
683 return byte_offset_of(Method, _method_counters);
684 }
685 #ifndef PRODUCT
686 static ByteSize compiled_invocation_counter_offset() { return byte_offset_of(Method, _compiled_invocation_count); }
687 #endif // not PRODUCT
688 static ByteSize native_function_offset() { return in_ByteSize(sizeof(Method)); }
689 static ByteSize from_interpreted_offset() { return byte_offset_of(Method, _from_interpreted_entry ); }
690 static ByteSize interpreter_entry_offset() { return byte_offset_of(Method, _i2i_entry ); }
691 static ByteSize signature_handler_offset() { return in_ByteSize(sizeof(Method) + wordSize); }
692 static ByteSize itable_index_offset() { return byte_offset_of(Method, _vtable_index ); }
693
694 // for code generation
695 static ByteSize method_data_offset() { return byte_offset_of(Method, _method_data); }
696 static ByteSize intrinsic_id_offset() { return byte_offset_of(Method, _intrinsic_id); }
697 static int intrinsic_id_size_in_bytes() { return sizeof(u2); }
698
699 // Static methods that are used to implement member methods where an exposed this pointer
700 // is needed due to possible GCs
701 static objArrayHandle resolved_checked_exceptions_impl(Method* method, TRAPS);
702
703 // Returns the byte code index from the byte code pointer
704 int bci_from(address bcp) const;
705 address bcp_from(int bci) const;
706 address bcp_from(address bcp) const;
707 int validate_bci_from_bcp(address bcp) const;
708 int validate_bci(int bci) const;
709
710 // Returns the line number for a bci if debugging information for the method is prowided,
711 // -1 is returned otherwise.
712 int line_number_from_bci(int bci) const;
713
714 // Reflection support
715 bool is_overridden_in(Klass* k) const;
716
717 // Stack walking support
718 bool is_ignored_by_security_stack_walk() const;
719
720 // JSR 292 support
721 bool is_method_handle_intrinsic() const; // MethodHandles::is_signature_polymorphic_intrinsic(intrinsic_id)
722 bool is_compiled_lambda_form() const; // intrinsic_id() == vmIntrinsics::_compiledLambdaForm
723 bool has_member_arg() const; // intrinsic_id() == vmIntrinsics::_linkToSpecial, etc.
724 static methodHandle make_method_handle_intrinsic(vmIntrinsicID iid, // _invokeBasic, _linkToVirtual
725 Symbol* signature, //anything at all
726 TRAPS);
727 // Some special methods don't need to be findable by nmethod iterators and are permanent.
728 bool can_be_allocated_in_NonNMethod_space() const { return is_method_handle_intrinsic(); }
729
730 // Continuation
731 inline bool is_continuation_enter_intrinsic() const;
732 inline bool is_continuation_yield_intrinsic() const;
733 inline bool is_continuation_native_intrinsic() const;
734 inline bool is_special_native_intrinsic() const;
735
736 static Klass* check_non_bcp_klass(Klass* klass);
737
738 enum {
739 // How many extra stack entries for invokedynamic
740 extra_stack_entries_for_jsr292 = 1
741 };
742
743 // this operates only on invoke methods:
744 // presize interpreter frames for extra interpreter stack entries, if needed
745 // Account for the extra appendix argument for invokehandle/invokedynamic
746 static int extra_stack_entries() { return extra_stack_entries_for_jsr292; }
747 static int extra_stack_words(); // = extra_stack_entries() * Interpreter::stackElementSize
748
749 // RedefineClasses() support:
750 bool on_stack() const { return on_stack_flag(); }
751 void set_on_stack(const bool value);
752
753 void record_gc_epoch();
754
755 // see the definition in Method*.cpp for the gory details
756 bool should_not_be_cached() const;
757
758 // Rewriting support
759 static methodHandle clone_with_new_data(const methodHandle& m, u_char* new_code, int new_code_length,
760 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS);
761
762 // jmethodID handling
763 // Because the useful life-span of a jmethodID cannot be determined,
764 // once created they are never reclaimed. The methods to which they refer,
765 // however, can be GC'ed away if the class is unloaded or if the method is
766 // made obsolete or deleted -- in these cases, the jmethodID
767 // refers to null (as is the case for any weak reference).
768 static jmethodID make_jmethod_id(ClassLoaderData* cld, Method* mh);
769 static void destroy_jmethod_id(ClassLoaderData* cld, jmethodID mid);
770
771 // Ensure there is enough capacity in the internal tracking data
772 // structures to hold the number of jmethodIDs you plan to generate.
773 // This saves substantial time doing allocations.
774 static void ensure_jmethod_ids(ClassLoaderData* cld, int capacity);
775
776 // Use resolve_jmethod_id() in situations where the caller is expected
777 // to provide a valid jmethodID; the only sanity checks are in asserts;
778 // result guaranteed not to be null.
779 inline static Method* resolve_jmethod_id(jmethodID mid) {
780 assert(mid != nullptr, "JNI method id should not be null");
781 return *((Method**)mid);
782 }
783
784 // Use checked_resolve_jmethod_id() in situations where the caller
785 // should provide a valid jmethodID, but might not. Null is returned
786 // when the jmethodID does not refer to a valid method.
787 static Method* checked_resolve_jmethod_id(jmethodID mid);
788
789 static void change_method_associated_with_jmethod_id(jmethodID old_jmid_ptr, Method* new_method);
790 static bool is_method_id(jmethodID mid);
791
792 // Clear methods
793 static void clear_jmethod_ids(ClassLoaderData* loader_data);
794 static void print_jmethod_ids_count(const ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
795
796 // Get this method's jmethodID -- allocate if it doesn't exist
797 jmethodID jmethod_id();
798
799 // Lookup the jmethodID for this method. Return null if not found.
800 // NOTE that this function can be called from a signal handler
801 // (see AsyncGetCallTrace support for Forte Analyzer) and this
802 // needs to be async-safe. No allocation should be done and
803 // so handles are not used to avoid deadlock.
804 jmethodID find_jmethod_id_or_null() { return method_holder()->jmethod_id_or_null(this); }
805
806 // Support for inlining of intrinsic methods
807 vmIntrinsicID intrinsic_id() const { return (vmIntrinsicID) _intrinsic_id; }
808 void set_intrinsic_id(vmIntrinsicID id) { _intrinsic_id = (u2) id; }
809
810 // Helper routines for intrinsic_id() and vmIntrinsics::method().
811 void init_intrinsic_id(vmSymbolID klass_id); // updates from _none if a match
812 static vmSymbolID klass_id_for_intrinsics(const Klass* holder);
813
814 bool caller_sensitive() const { return constMethod()->caller_sensitive(); }
815 void set_caller_sensitive() { constMethod()->set_caller_sensitive(); }
816
817 bool changes_current_thread() const { return constMethod()->changes_current_thread(); }
818 void set_changes_current_thread() { constMethod()->set_changes_current_thread(); }
819
820 bool jvmti_mount_transition() const { return constMethod()->jvmti_mount_transition(); }
821 void set_jvmti_mount_transition() { constMethod()->set_jvmti_mount_transition(); }
822
823 bool is_hidden() const { return constMethod()->is_hidden(); }
824 void set_is_hidden() { constMethod()->set_is_hidden(); }
825
826 bool is_scoped() const { return constMethod()->is_scoped(); }
827 void set_scoped() { constMethod()->set_is_scoped(); }
828
829 bool intrinsic_candidate() const { return constMethod()->intrinsic_candidate(); }
830 void set_intrinsic_candidate() { constMethod()->set_intrinsic_candidate(); }
831
832 bool has_injected_profile() const { return constMethod()->has_injected_profile(); }
833 void set_has_injected_profile() { constMethod()->set_has_injected_profile(); }
834
835 bool has_reserved_stack_access() const { return constMethod()->reserved_stack_access(); }
836 void set_has_reserved_stack_access() { constMethod()->set_reserved_stack_access(); }
837
838 bool has_scalarized_args() const { return constMethod()->has_scalarized_args(); }
839 void set_has_scalarized_args() { constMethod()->set_has_scalarized_args(); }
840
841 bool has_scalarized_return() const { return constMethod()->has_scalarized_return(); }
842 void set_has_scalarized_return() { constMethod()->set_has_scalarized_return(); }
843
844 bool is_scalarized_arg(int idx) const;
845
846 bool c1_needs_stack_repair() const { return constMethod()->c1_needs_stack_repair(); }
847 void set_c1_needs_stack_repair() { constMethod()->set_c1_needs_stack_repair(); }
848
849 bool c2_needs_stack_repair() const { return constMethod()->c2_needs_stack_repair(); }
850 void set_c2_needs_stack_repair() { constMethod()->set_c2_needs_stack_repair(); }
851
852 bool mismatch() const { return constMethod()->mismatch(); }
853 void set_mismatch() { constMethod()->set_mismatch(); }
854
855 JFR_ONLY(DEFINE_TRACE_FLAG_ACCESSOR;)
856
857 ConstMethod::MethodType method_type() const {
858 return _constMethod->method_type();
859 }
860 bool is_overpass() const { return method_type() == ConstMethod::OVERPASS; }
861
862 // On-stack replacement support
863 bool has_osr_nmethod(int level, bool match_level) {
864 return method_holder()->lookup_osr_nmethod(this, InvocationEntryBci, level, match_level) != nullptr;
865 }
866
867 nmethod* lookup_osr_nmethod_for(int bci, int level, bool match_level) {
868 return method_holder()->lookup_osr_nmethod(this, bci, level, match_level);
869 }
870
871 // Find if klass for method is loaded
872 bool is_klass_loaded_by_klass_index(int klass_index) const;
873 bool is_klass_loaded(int refinfo_index, Bytecodes::Code bc, bool must_be_resolved = false) const;
874
875 // Indicates whether compilation failed earlier for this method, or
876 // whether it is not compilable for another reason like having a
877 // breakpoint set in it.
878 bool is_not_compilable(int comp_level = CompLevel_any) const;
879 void set_not_compilable(const char* reason, int comp_level = CompLevel_all, bool report = true);
880 void set_not_compilable_quietly(const char* reason, int comp_level = CompLevel_all) {
881 set_not_compilable(reason, comp_level, false);
882 }
883 bool is_not_osr_compilable(int comp_level = CompLevel_any) const;
884 void set_not_osr_compilable(const char* reason, int comp_level = CompLevel_all, bool report = true);
885 void set_not_osr_compilable_quietly(const char* reason, int comp_level = CompLevel_all) {
886 set_not_osr_compilable(reason, comp_level, false);
887 }
888 bool is_always_compilable() const;
889
890 private:
891 void print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason);
892
893 public:
894 MethodCounters* get_method_counters(Thread* current) {
895 if (_method_counters == nullptr) {
896 build_method_counters(current, this);
897 }
898 return _method_counters;
899 }
900
901 void clear_is_not_c1_compilable() { set_is_not_c1_compilable(false); }
902 void clear_is_not_c2_compilable() { set_is_not_c2_compilable(false); }
903 void clear_is_not_c2_osr_compilable() { set_is_not_c2_osr_compilable(false); }
904
905 // not_c1_osr_compilable == not_c1_compilable
906 bool is_not_c1_osr_compilable() const { return is_not_c1_compilable(); }
907 void set_is_not_c1_osr_compilable() { set_is_not_c1_compilable(); }
908 void clear_is_not_c1_osr_compilable() { clear_is_not_c1_compilable(); }
909
910 // Background compilation support
911 void clear_queued_for_compilation() { set_queued_for_compilation(false); }
912
913 // Resolve all classes in signature, return 'true' if successful
914 static bool load_signature_classes(const methodHandle& m, TRAPS);
915
916 // Printing
917 void print_short_name(outputStream* st = tty) const; // prints as klassname::methodname; Exposed so field engineers can debug VM
918 #if INCLUDE_JVMTI
919 void print_name(outputStream* st = tty) const; // prints as "virtual void foo(int)"; exposed for -Xlog:redefine+class
920 #else
921 void print_name(outputStream* st = tty) const PRODUCT_RETURN; // prints as "virtual void foo(int)"
922 #endif
923
924 typedef int (*method_comparator_func)(Method* a, Method* b);
925
926 // Helper routine used for method sorting
927 static void sort_methods(Array<Method*>* methods, bool set_idnums = true, method_comparator_func func = nullptr);
928
929 // Deallocation function for redefine classes or if an error occurs
930 void deallocate_contents(ClassLoaderData* loader_data);
931
932 void release_C_heap_structures();
933
934 Method* get_new_method() const {
935 InstanceKlass* holder = method_holder();
936 Method* new_method = holder->method_with_idnum(orig_method_idnum());
937
938 assert(new_method != nullptr, "method_with_idnum() should not be null");
939 assert(this != new_method, "sanity check");
940 return new_method;
941 }
942
943 // Printing
944 #ifndef PRODUCT
945 void print_on(outputStream* st) const;
946 #endif
947 void print_value_on(outputStream* st) const;
948 void print_linkage_flags(outputStream* st) PRODUCT_RETURN;
949
950 const char* internal_name() const { return "{method}"; }
951
952 // Check for valid method pointer
953 static bool has_method_vptr(const void* ptr);
954 static bool is_valid_method(const Method* m);
955
956 // Verify
957 void verify() { verify_on(tty); }
958 void verify_on(outputStream* st);
959
960 private:
961
962 // Inlined elements
963 address* native_function_addr() const { assert(is_native(), "must be native"); return (address*) (this+1); }
964 address* signature_handler_addr() const { return native_function_addr() + 1; }
965 };
966
967
968 // Utility class for compressing line number tables
969
970 class CompressedLineNumberWriteStream: public CompressedWriteStream {
971 private:
972 int _bci;
973 int _line;
974 public:
975 // Constructor
976 CompressedLineNumberWriteStream(int initial_size) : CompressedWriteStream(initial_size), _bci(0), _line(0) {}
977 CompressedLineNumberWriteStream(u_char* buffer, int initial_size) : CompressedWriteStream(buffer, initial_size), _bci(0), _line(0) {}
978
979 // Write (bci, line number) pair to stream
980 void write_pair_regular(int bci_delta, int line_delta);
981
982 // If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
983 // we save it as one byte, otherwise we write a 0xFF escape character
984 // and use regular compression. 0x0 is used as end-of-stream terminator.
985 void write_pair_inline(int bci, int line);
986
987 void write_pair(int bci, int line);
988
989 // Write end-of-stream marker
990 void write_terminator() { write_byte(0); }
991 };
992
993
994 // Utility class for decompressing line number tables
995
996 class CompressedLineNumberReadStream: public CompressedReadStream {
997 private:
998 int _bci;
999 int _line;
1000 public:
1001 // Constructor
1002 CompressedLineNumberReadStream(u_char* buffer);
1003 // Read (bci, line number) pair from stream. Returns false at end-of-stream.
1004 bool read_pair();
1005 // Accessing bci and line number (after calling read_pair)
1006 int bci() const { return _bci; }
1007 int line() const { return _line; }
1008 };
1009
1010
1011 #if INCLUDE_JVMTI
1012
1013 /// Fast Breakpoints.
1014
1015 // If this structure gets more complicated (because bpts get numerous),
1016 // move it into its own header.
1017
1018 // There is presently no provision for concurrent access
1019 // to breakpoint lists, which is only OK for JVMTI because
1020 // breakpoints are written only at safepoints, and are read
1021 // concurrently only outside of safepoints.
1022
1023 class BreakpointInfo : public CHeapObj<mtClass> {
1024 friend class VMStructs;
1025 private:
1026 Bytecodes::Code _orig_bytecode;
1027 int _bci;
1028 u2 _name_index; // of method
1029 u2 _signature_index; // of method
1030 BreakpointInfo* _next; // simple storage allocation
1031
1032 public:
1033 BreakpointInfo(Method* m, int bci);
1034
1035 // accessors
1036 Bytecodes::Code orig_bytecode() { return _orig_bytecode; }
1037 void set_orig_bytecode(Bytecodes::Code code) { _orig_bytecode = code; }
1038 int bci() { return _bci; }
1039
1040 BreakpointInfo* next() const { return _next; }
1041 void set_next(BreakpointInfo* n) { _next = n; }
1042
1043 // helps for searchers
1044 bool match(const Method* m, int bci) {
1045 return bci == _bci && match(m);
1046 }
1047
1048 bool match(const Method* m) {
1049 return _name_index == m->name_index() &&
1050 _signature_index == m->signature_index();
1051 }
1052
1053 void set(Method* method);
1054 void clear(Method* method);
1055 };
1056
1057 #endif // INCLUDE_JVMTI
1058
1059 // Utility class for access exception handlers
1060 class ExceptionTable : public StackObj {
1061 private:
1062 ExceptionTableElement* _table;
1063 u2 _length;
1064
1065 public:
1066 ExceptionTable(const Method* m) {
1067 if (m->has_exception_handler()) {
1068 _table = m->exception_table_start();
1069 _length = m->exception_table_length();
1070 } else {
1071 _table = nullptr;
1072 _length = 0;
1073 }
1074 }
1075
1076 u2 length() const {
1077 return _length;
1078 }
1079
1080 u2 start_pc(int idx) const {
1081 assert(idx < _length, "out of bounds");
1082 return _table[idx].start_pc;
1083 }
1084
1085 void set_start_pc(int idx, u2 value) {
1086 assert(idx < _length, "out of bounds");
1087 _table[idx].start_pc = value;
1088 }
1089
1090 u2 end_pc(int idx) const {
1091 assert(idx < _length, "out of bounds");
1092 return _table[idx].end_pc;
1093 }
1094
1095 void set_end_pc(int idx, u2 value) {
1096 assert(idx < _length, "out of bounds");
1097 _table[idx].end_pc = value;
1098 }
1099
1100 u2 handler_pc(int idx) const {
1101 assert(idx < _length, "out of bounds");
1102 return _table[idx].handler_pc;
1103 }
1104
1105 void set_handler_pc(int idx, u2 value) {
1106 assert(idx < _length, "out of bounds");
1107 _table[idx].handler_pc = value;
1108 }
1109
1110 u2 catch_type_index(int idx) const {
1111 assert(idx < _length, "out of bounds");
1112 return _table[idx].catch_type_index;
1113 }
1114
1115 void set_catch_type_index(int idx, u2 value) {
1116 assert(idx < _length, "out of bounds");
1117 _table[idx].catch_type_index = value;
1118 }
1119 };
1120
1121 #endif // SHARE_OOPS_METHOD_HPP