1 /*
2 * Copyright (c) 1997, 2012, 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.
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23 */
24
25 #ifndef SHARE_VM_OOPS_METHODOOP_HPP
26 #define SHARE_VM_OOPS_METHODOOP_HPP
27
28 #include "classfile/vmSymbols.hpp"
29 #include "code/compressedStream.hpp"
30 #include "compiler/oopMap.hpp"
31 #include "interpreter/invocationCounter.hpp"
32 #include "oops/annotations.hpp"
33 #include "oops/constantPool.hpp"
34 #include "oops/instanceKlass.hpp"
35 #include "oops/oop.hpp"
36 #include "oops/typeArrayOop.hpp"
37 #include "utilities/accessFlags.hpp"
38 #include "utilities/growableArray.hpp"
39
40 // A Method* represents a Java method.
41 //
42 // Memory layout (each line represents a word). Note that most applications load thousands of methods,
43 // so keeping the size of this structure small has a big impact on footprint.
44 //
45 // We put all oops and method_size first for better gc cache locality.
46 //
47 // The actual bytecodes are inlined after the end of the Method struct.
48 //
49 // There are bits in the access_flags telling whether inlined tables are present.
50 // Note that accessing the line number and local variable tables is not performance critical at all.
51 // Accessing the checked exceptions table is used by reflection, so we put that last to make access
52 // to it fast.
53 //
54 // The line number table is compressed and inlined following the byte codes. It is found as the first
55 // byte following the byte codes. The checked exceptions table and the local variable table are inlined
56 // after the line number table, and indexed from the end of the method. We do not compress the checked
57 // exceptions table since the average length is less than 2, and do not bother to compress the local
58 // variable table either since it is mostly absent.
59 //
60 // Note that native_function and signature_handler has to be at fixed offsets (required by the interpreter)
61 //
62 // |------------------------------------------------------|
63 // | header |
64 // | klass |
65 // |------------------------------------------------------|
66 // | ConstMethod* (oop) |
67 // |------------------------------------------------------|
68 // | methodData (oop) |
69 // | interp_invocation_count |
70 // |------------------------------------------------------|
71 // | access_flags |
72 // | vtable_index |
73 // |------------------------------------------------------|
74 // | result_index (C++ interpreter only) |
75 // |------------------------------------------------------|
76 // | method_size | intrinsic_id| flags |
77 // |------------------------------------------------------|
78 // | throwout_count | num_breakpoints |
79 // |------------------------------------------------------|
80 // | invocation_counter |
81 // | backedge_counter |
82 // |------------------------------------------------------|
83 // | prev_time (tiered only, 64 bit wide) |
84 // | |
85 // |------------------------------------------------------|
86 // | rate (tiered) |
87 // |------------------------------------------------------|
88 // | code (pointer) |
89 // | i2i (pointer) |
90 // | adapter (pointer) |
91 // | from_compiled_entry (pointer) |
92 // | from_interpreted_entry (pointer) |
93 // |------------------------------------------------------|
94 // | native_function (present only if native) |
95 // | signature_handler (present only if native) |
96 // |------------------------------------------------------|
97
98
99 class CheckedExceptionElement;
100 class LocalVariableTableElement;
101 class AdapterHandlerEntry;
102 class MethodData;
103 class ConstMethod;
104
105 class Method : public Metadata {
106 friend class VMStructs;
107 private:
108 ConstMethod* _constMethod; // Method read-only data.
109 MethodData* _method_data;
110 int _interpreter_invocation_count; // Count of times invoked (reused as prev_event_count in tiered)
111 AccessFlags _access_flags; // Access flags
112 int _vtable_index; // vtable index of this method (see VtableIndexFlag)
113 // note: can have vtables with >2**16 elements (because of inheritance)
114 #ifdef CC_INTERP
115 int _result_index; // C++ interpreter needs for converting results to/from stack
116 #endif
117 u2 _method_size; // size of this object
118 u1 _intrinsic_id; // vmSymbols::intrinsic_id (0 == _none)
119 u1 _jfr_towrite : 1, // Flags
120 _force_inline : 1,
121 _hidden : 1,
122 _dont_inline : 1,
123 : 4;
124 u2 _interpreter_throwout_count; // Count of times method was exited via exception while interpreting
125 u2 _number_of_breakpoints; // fullspeed debugging support
126 InvocationCounter _invocation_counter; // Incremented before each activation of the method - used to trigger frequency-based optimizations
127 InvocationCounter _backedge_counter; // Incremented before each backedge taken - used to trigger frequencey-based optimizations
128
129 #ifdef TIERED
130 jlong _prev_time; // Previous time the rate was acquired
131 float _rate; // Events (invocation and backedge counter increments) per millisecond
132 #endif
133
134 #ifndef PRODUCT
135 int _compiled_invocation_count; // Number of nmethod invocations so far (for perf. debugging)
136 #endif
137 // Entry point for calling both from and to the interpreter.
138 address _i2i_entry; // All-args-on-stack calling convention
139 // Adapter blob (i2c/c2i) for this Method*. Set once when method is linked.
140 AdapterHandlerEntry* _adapter;
141 // Entry point for calling from compiled code, to compiled code if it exists
142 // or else the interpreter.
143 volatile address _from_compiled_entry; // Cache of: _code ? _code->entry_point() : _adapter->c2i_entry()
144 // The entry point for calling both from and to compiled code is
145 // "_code->entry_point()". Because of tiered compilation and de-opt, this
146 // field can come and go. It can transition from NULL to not-null at any
147 // time (whenever a compile completes). It can transition from not-null to
148 // NULL only at safepoints (because of a de-opt).
149 nmethod* volatile _code; // Points to the corresponding piece of native code
150 volatile address _from_interpreted_entry; // Cache of _code ? _adapter->i2c_entry() : _i2i_entry
151
152 // Constructor
153 Method(ConstMethod* xconst, AccessFlags access_flags, int size);
154 public:
155
156 static Method* allocate(ClassLoaderData* loader_data,
157 int byte_code_size,
158 AccessFlags access_flags,
159 int compressed_line_number_size,
160 int localvariable_table_length,
161 int exception_table_length,
162 int checked_exceptions_length,
163 int method_parameters_length,
164 u2 generic_signature_index,
165 ConstMethod::MethodType method_type,
166 TRAPS);
167
168 // CDS and vtbl checking can create an empty Method to get vtbl pointer.
169 Method(){}
170
171 // The Method vtable is restored by this call when the Method is in the
172 // shared archive. See patch_klass_vtables() in metaspaceShared.cpp for
173 // all the gory details. SA, dtrace and pstack helpers distinguish metadata
174 // by their vtable.
175 void restore_vtable() { guarantee(is_method(), "vtable restored by this call"); }
176 bool is_method() const volatile { return true; }
177
178 // accessors for instance variables
179
180 ConstMethod* constMethod() const { return _constMethod; }
181 void set_constMethod(ConstMethod* xconst) { _constMethod = xconst; }
182
183
184 static address make_adapters(methodHandle mh, TRAPS);
185 volatile address from_compiled_entry() const { return (address)OrderAccess::load_ptr_acquire(&_from_compiled_entry); }
186 volatile address from_interpreted_entry() const{ return (address)OrderAccess::load_ptr_acquire(&_from_interpreted_entry); }
187
188 // access flag
189 AccessFlags access_flags() const { return _access_flags; }
190 void set_access_flags(AccessFlags flags) { _access_flags = flags; }
191
192 // name
193 Symbol* name() const { return constants()->symbol_at(name_index()); }
194 int name_index() const { return constMethod()->name_index(); }
195 void set_name_index(int index) { constMethod()->set_name_index(index); }
196
197 // signature
198 Symbol* signature() const { return constants()->symbol_at(signature_index()); }
199 int signature_index() const { return constMethod()->signature_index(); }
200 void set_signature_index(int index) { constMethod()->set_signature_index(index); }
201
202 // generics support
203 Symbol* generic_signature() const { int idx = generic_signature_index(); return ((idx != 0) ? constants()->symbol_at(idx) : (Symbol*)NULL); }
204 int generic_signature_index() const { return constMethod()->generic_signature_index(); }
205 void set_generic_signature_index(int index) { constMethod()->set_generic_signature_index(index); }
206
207 // annotations support
208 AnnotationArray* annotations() const {
209 InstanceKlass* ik = method_holder();
210 if (ik->annotations() == NULL) {
211 return NULL;
212 }
213 return ik->annotations()->get_method_annotations_of(method_idnum());
214 }
215 AnnotationArray* parameter_annotations() const {
216 InstanceKlass* ik = method_holder();
217 if (ik->annotations() == NULL) {
218 return NULL;
219 }
220 return ik->annotations()->get_method_parameter_annotations_of(method_idnum());
221 }
222 AnnotationArray* annotation_default() const {
223 InstanceKlass* ik = method_holder();
224 if (ik->annotations() == NULL) {
225 return NULL;
226 }
227 return ik->annotations()->get_method_default_annotations_of(method_idnum());
228 }
229 AnnotationArray* type_annotations() const {
230 InstanceKlass* ik = method_holder();
231 Annotations* type_annos = ik->type_annotations();
232 if (type_annos == NULL)
233 return NULL;
234 return type_annos->get_method_annotations_of(method_idnum());
235 }
236
237 #ifdef CC_INTERP
238 void set_result_index(BasicType type);
239 int result_index() { return _result_index; }
240 #endif
241
242 // Helper routine: get klass name + "." + method name + signature as
243 // C string, for the purpose of providing more useful NoSuchMethodErrors
244 // and fatal error handling. The string is allocated in resource
245 // area if a buffer is not provided by the caller.
246 char* name_and_sig_as_C_string() const;
247 char* name_and_sig_as_C_string(char* buf, int size) const;
248
249 // Static routine in the situations we don't have a Method*
250 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature);
251 static char* name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size);
252
253 Bytecodes::Code java_code_at(int bci) const {
254 return Bytecodes::java_code_at(this, bcp_from(bci));
255 }
256 Bytecodes::Code code_at(int bci) const {
257 return Bytecodes::code_at(this, bcp_from(bci));
258 }
259
260 // JVMTI breakpoints
261 Bytecodes::Code orig_bytecode_at(int bci) const;
262 void set_orig_bytecode_at(int bci, Bytecodes::Code code);
263 void set_breakpoint(int bci);
264 void clear_breakpoint(int bci);
265 void clear_all_breakpoints();
266 // Tracking number of breakpoints, for fullspeed debugging.
267 // Only mutated by VM thread.
268 u2 number_of_breakpoints() const { return _number_of_breakpoints; }
269 void incr_number_of_breakpoints() { ++_number_of_breakpoints; }
270 void decr_number_of_breakpoints() { --_number_of_breakpoints; }
271 // Initialization only
272 void clear_number_of_breakpoints() { _number_of_breakpoints = 0; }
273
274 // index into InstanceKlass methods() array
275 // note: also used by jfr
276 u2 method_idnum() const { return constMethod()->method_idnum(); }
277 void set_method_idnum(u2 idnum) { constMethod()->set_method_idnum(idnum); }
278
279 // code size
280 int code_size() const { return constMethod()->code_size(); }
281
282 // method size
283 int method_size() const { return _method_size; }
284 void set_method_size(int size) {
285 assert(0 <= size && size < (1 << 16), "invalid method size");
286 _method_size = size;
287 }
288
289 // constant pool for Klass* holding this method
290 ConstantPool* constants() const { return constMethod()->constants(); }
291 void set_constants(ConstantPool* c) { constMethod()->set_constants(c); }
292
293 // max stack
294 // return original max stack size for method verification
295 int verifier_max_stack() const { return constMethod()->max_stack(); }
296 int max_stack() const { return constMethod()->max_stack() + extra_stack_entries(); }
297 void set_max_stack(int size) { constMethod()->set_max_stack(size); }
298
299 // max locals
300 int max_locals() const { return constMethod()->max_locals(); }
301 void set_max_locals(int size) { constMethod()->set_max_locals(size); }
302
303 int highest_comp_level() const;
304 void set_highest_comp_level(int level);
305 int highest_osr_comp_level() const;
306 void set_highest_osr_comp_level(int level);
307
308 // Count of times method was exited via exception while interpreting
309 void interpreter_throwout_increment() {
310 if (_interpreter_throwout_count < 65534) {
311 _interpreter_throwout_count++;
312 }
313 }
314
315 int interpreter_throwout_count() const { return _interpreter_throwout_count; }
316 void set_interpreter_throwout_count(int count) { _interpreter_throwout_count = count; }
317
318 // size of parameters
319 int size_of_parameters() const { return constMethod()->size_of_parameters(); }
320 void set_size_of_parameters(int size) { constMethod()->set_size_of_parameters(size); }
321
322 bool has_stackmap_table() const {
323 return constMethod()->has_stackmap_table();
324 }
325
326 Array<u1>* stackmap_data() const {
327 return constMethod()->stackmap_data();
328 }
329
330 void set_stackmap_data(Array<u1>* sd) {
331 constMethod()->set_stackmap_data(sd);
332 }
333
334 // exception handler table
335 bool has_exception_handler() const
336 { return constMethod()->has_exception_handler(); }
337 int exception_table_length() const
338 { return constMethod()->exception_table_length(); }
339 ExceptionTableElement* exception_table_start() const
340 { return constMethod()->exception_table_start(); }
341
342 // Finds the first entry point bci of an exception handler for an
343 // exception of klass ex_klass thrown at throw_bci. A value of NULL
344 // for ex_klass indicates that the exception klass is not known; in
345 // this case it matches any constraint class. Returns -1 if the
346 // exception cannot be handled in this method. The handler
347 // constraint classes are loaded if necessary. Note that this may
348 // throw an exception if loading of the constraint classes causes
349 // an IllegalAccessError (bugid 4307310) or an OutOfMemoryError.
350 // If an exception is thrown, returns the bci of the
351 // exception handler which caused the exception to be thrown, which
352 // is needed for proper retries. See, for example,
353 // InterpreterRuntime::exception_handler_for_exception.
354 static int fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS);
355
356 // method data access
357 MethodData* method_data() const {
358 return _method_data;
359 }
360 void set_method_data(MethodData* data) {
361 _method_data = data;
362 }
363
364 // invocation counter
365 InvocationCounter* invocation_counter() { return &_invocation_counter; }
366 InvocationCounter* backedge_counter() { return &_backedge_counter; }
367
368 #ifdef TIERED
369 // We are reusing interpreter_invocation_count as a holder for the previous event count!
370 // We can do that since interpreter_invocation_count is not used in tiered.
371 int prev_event_count() const { return _interpreter_invocation_count; }
372 void set_prev_event_count(int count) { _interpreter_invocation_count = count; }
373 jlong prev_time() const { return _prev_time; }
374 void set_prev_time(jlong time) { _prev_time = time; }
375 float rate() const { return _rate; }
376 void set_rate(float rate) { _rate = rate; }
377 #endif
378
379 int invocation_count();
380 int backedge_count();
381
382 bool was_executed_more_than(int n);
383 bool was_never_executed() { return !was_executed_more_than(0); }
384
385 static void build_interpreter_method_data(methodHandle method, TRAPS);
386
387 int interpreter_invocation_count() {
388 if (TieredCompilation) return invocation_count();
389 else return _interpreter_invocation_count;
390 }
391 void set_interpreter_invocation_count(int count) { _interpreter_invocation_count = count; }
392 int increment_interpreter_invocation_count() {
393 if (TieredCompilation) ShouldNotReachHere();
394 return ++_interpreter_invocation_count;
395 }
396
397 #ifndef PRODUCT
398 int compiled_invocation_count() const { return _compiled_invocation_count; }
399 void set_compiled_invocation_count(int count) { _compiled_invocation_count = count; }
400 #endif // not PRODUCT
401
402 // Clear (non-shared space) pointers which could not be relevant
403 // if this (shared) method were mapped into another JVM.
404 void remove_unshareable_info();
405
406 // nmethod/verified compiler entry
407 address verified_code_entry();
408 bool check_code() const; // Not inline to avoid circular ref
409 nmethod* volatile code() const { assert( check_code(), "" ); return (nmethod *)OrderAccess::load_ptr_acquire(&_code); }
410 void clear_code(); // Clear out any compiled code
411 static void set_code(methodHandle mh, nmethod* code);
412 void set_adapter_entry(AdapterHandlerEntry* adapter) { _adapter = adapter; }
413 address get_i2c_entry();
414 address get_c2i_entry();
415 address get_c2i_unverified_entry();
416 AdapterHandlerEntry* adapter() { return _adapter; }
417 // setup entry points
418 void link_method(methodHandle method, TRAPS);
419 // clear entry points. Used by sharing code
420 void unlink_method();
421
422 // vtable index
423 enum VtableIndexFlag {
424 // Valid vtable indexes are non-negative (>= 0).
425 // These few negative values are used as sentinels.
426 highest_unused_vtable_index_value = -5,
427 invalid_vtable_index = -4, // distinct from any valid vtable index
428 garbage_vtable_index = -3, // not yet linked; no vtable layout yet
429 nonvirtual_vtable_index = -2 // there is no need for vtable dispatch
430 // 6330203 Note: Do not use -1, which was overloaded with many meanings.
431 };
432 DEBUG_ONLY(bool valid_vtable_index() const { return _vtable_index >= nonvirtual_vtable_index; })
433 int vtable_index() const { assert(valid_vtable_index(), "");
434 return _vtable_index; }
435 void set_vtable_index(int index) { _vtable_index = index; }
436
437 // interpreter entry
438 address interpreter_entry() const { return _i2i_entry; }
439 // Only used when first initialize so we can set _i2i_entry and _from_interpreted_entry
440 void set_interpreter_entry(address entry) { _i2i_entry = entry; _from_interpreted_entry = entry; }
441 int interpreter_kind(void) {
442 return constMethod()->interpreter_kind();
443 }
444 void set_interpreter_kind();
445 void set_interpreter_kind(int kind) {
446 constMethod()->set_interpreter_kind(kind);
447 }
448
449 // native function (used for native methods only)
450 enum {
451 native_bind_event_is_interesting = true
452 };
453 address native_function() const { return *(native_function_addr()); }
454 address critical_native_function();
455
456 // Must specify a real function (not NULL).
457 // Use clear_native_function() to unregister.
458 void set_native_function(address function, bool post_event_flag);
459 bool has_native_function() const;
460 void clear_native_function();
461
462 // signature handler (used for native methods only)
463 address signature_handler() const { return *(signature_handler_addr()); }
464 void set_signature_handler(address handler);
465
466 // Interpreter oopmap support
467 void mask_for(int bci, InterpreterOopMap* mask);
468
469 #ifndef PRODUCT
470 // operations on invocation counter
471 void print_invocation_count();
472 #endif
473
474 // byte codes
475 void set_code(address code) { return constMethod()->set_code(code); }
476 address code_base() const { return constMethod()->code_base(); }
477 bool contains(address bcp) const { return constMethod()->contains(bcp); }
478
479 // prints byte codes
480 void print_codes() const { print_codes_on(tty); }
481 void print_codes_on(outputStream* st) const PRODUCT_RETURN;
482 void print_codes_on(int from, int to, outputStream* st) const PRODUCT_RETURN;
483
484 // method parameters
485 int method_parameters_length() const
486 { return constMethod()->method_parameters_length(); }
487 MethodParametersElement* method_parameters_start() const
488 { return constMethod()->method_parameters_start(); }
489
490 // checked exceptions
491 int checked_exceptions_length() const
492 { return constMethod()->checked_exceptions_length(); }
493 CheckedExceptionElement* checked_exceptions_start() const
494 { return constMethod()->checked_exceptions_start(); }
495
496 // localvariable table
497 bool has_localvariable_table() const
498 { return constMethod()->has_localvariable_table(); }
499 int localvariable_table_length() const
500 { return constMethod()->localvariable_table_length(); }
501 LocalVariableTableElement* localvariable_table_start() const
502 { return constMethod()->localvariable_table_start(); }
503
504 bool has_linenumber_table() const
505 { return constMethod()->has_linenumber_table(); }
506 u_char* compressed_linenumber_table() const
507 { return constMethod()->compressed_linenumber_table(); }
508
509 // method holder (the Klass* holding this method)
510 InstanceKlass* method_holder() const { return constants()->pool_holder(); }
511
512 void compute_size_of_parameters(Thread *thread); // word size of parameters (receiver if any + arguments)
513 Symbol* klass_name() const; // returns the name of the method holder
514 BasicType result_type() const; // type of the method result
515 int result_type_index() const; // type index of the method result
516 bool is_returning_oop() const { BasicType r = result_type(); return (r == T_OBJECT || r == T_ARRAY); }
517 bool is_returning_fp() const { BasicType r = result_type(); return (r == T_FLOAT || r == T_DOUBLE); }
518
519 // Checked exceptions thrown by this method (resolved to mirrors)
520 objArrayHandle resolved_checked_exceptions(TRAPS) { return resolved_checked_exceptions_impl(this, THREAD); }
521
522 // Access flags
523 bool is_public() const { return access_flags().is_public(); }
524 bool is_private() const { return access_flags().is_private(); }
525 bool is_protected() const { return access_flags().is_protected(); }
526 bool is_package_private() const { return !is_public() && !is_private() && !is_protected(); }
527 bool is_static() const { return access_flags().is_static(); }
528 bool is_final() const { return access_flags().is_final(); }
529 bool is_synchronized() const { return access_flags().is_synchronized();}
530 bool is_native() const { return access_flags().is_native(); }
531 bool is_abstract() const { return access_flags().is_abstract(); }
532 bool is_strict() const { return access_flags().is_strict(); }
533 bool is_synthetic() const { return access_flags().is_synthetic(); }
534
535 // returns true if contains only return operation
536 bool is_empty_method() const;
537
538 // returns true if this is a vanilla constructor
539 bool is_vanilla_constructor() const;
540
541 // checks method and its method holder
542 bool is_final_method() const;
543 bool is_strict_method() const;
544
545 // true if method needs no dynamic dispatch (final and/or no vtable entry)
546 bool can_be_statically_bound() const;
547
548 // returns true if the method has any backward branches.
549 bool has_loops() {
550 return access_flags().loops_flag_init() ? access_flags().has_loops() : compute_has_loops_flag();
551 };
552
553 bool compute_has_loops_flag();
554
555 bool has_jsrs() {
556 return access_flags().has_jsrs();
557 };
558 void set_has_jsrs() {
559 _access_flags.set_has_jsrs();
560 }
561
562 // returns true if the method has any monitors.
563 bool has_monitors() const { return is_synchronized() || access_flags().has_monitor_bytecodes(); }
564 bool has_monitor_bytecodes() const { return access_flags().has_monitor_bytecodes(); }
565
566 void set_has_monitor_bytecodes() { _access_flags.set_has_monitor_bytecodes(); }
567
568 // monitor matching. This returns a conservative estimate of whether the monitorenter/monitorexit bytecodes
569 // propererly nest in the method. It might return false, even though they actually nest properly, since the info.
570 // has not been computed yet.
571 bool guaranteed_monitor_matching() const { return access_flags().is_monitor_matching(); }
572 void set_guaranteed_monitor_matching() { _access_flags.set_monitor_matching(); }
573
574 // returns true if the method is an accessor function (setter/getter).
575 bool is_accessor() const;
576
577 // returns true if the method is an initializer (<init> or <clinit>).
578 bool is_initializer() const;
579
580 // returns true if the method is static OR if the classfile version < 51
581 bool has_valid_initializer_flags() const;
582
583 // returns true if the method name is <clinit> and the method has
584 // valid static initializer flags.
585 bool is_static_initializer() const;
586
587 // compiled code support
588 // NOTE: code() is inherently racy as deopt can be clearing code
589 // simultaneously. Use with caution.
590 bool has_compiled_code() const { return code() != NULL; }
591
592 // sizing
593 static int header_size() { return sizeof(Method)/HeapWordSize; }
594 static int size(bool is_native);
595 int size() const { return method_size(); }
596
597 // interpreter support
598 static ByteSize const_offset() { return byte_offset_of(Method, _constMethod ); }
599 static ByteSize access_flags_offset() { return byte_offset_of(Method, _access_flags ); }
600 #ifdef CC_INTERP
601 static ByteSize result_index_offset() { return byte_offset_of(Method, _result_index ); }
602 #endif /* CC_INTERP */
603 static ByteSize from_compiled_offset() { return byte_offset_of(Method, _from_compiled_entry); }
604 static ByteSize code_offset() { return byte_offset_of(Method, _code); }
605 static ByteSize invocation_counter_offset() { return byte_offset_of(Method, _invocation_counter); }
606 static ByteSize backedge_counter_offset() { return byte_offset_of(Method, _backedge_counter); }
607 static ByteSize method_data_offset() {
608 return byte_offset_of(Method, _method_data);
609 }
610 static ByteSize interpreter_invocation_counter_offset() { return byte_offset_of(Method, _interpreter_invocation_count); }
611 #ifndef PRODUCT
612 static ByteSize compiled_invocation_counter_offset() { return byte_offset_of(Method, _compiled_invocation_count); }
613 #endif // not PRODUCT
614 static ByteSize native_function_offset() { return in_ByteSize(sizeof(Method)); }
615 static ByteSize from_interpreted_offset() { return byte_offset_of(Method, _from_interpreted_entry ); }
616 static ByteSize interpreter_entry_offset() { return byte_offset_of(Method, _i2i_entry ); }
617 static ByteSize signature_handler_offset() { return in_ByteSize(sizeof(Method) + wordSize); }
618
619 // for code generation
620 static int method_data_offset_in_bytes() { return offset_of(Method, _method_data); }
621 static int interpreter_invocation_counter_offset_in_bytes()
622 { return offset_of(Method, _interpreter_invocation_count); }
623 static int intrinsic_id_offset_in_bytes() { return offset_of(Method, _intrinsic_id); }
624 static int intrinsic_id_size_in_bytes() { return sizeof(u1); }
625
626 // Static methods that are used to implement member methods where an exposed this pointer
627 // is needed due to possible GCs
628 static objArrayHandle resolved_checked_exceptions_impl(Method* this_oop, TRAPS);
629
630 // Returns the byte code index from the byte code pointer
631 int bci_from(address bcp) const;
632 address bcp_from(int bci) const;
633 int validate_bci_from_bcx(intptr_t bcx) const;
634
635 // Returns the line number for a bci if debugging information for the method is prowided,
636 // -1 is returned otherwise.
637 int line_number_from_bci(int bci) const;
638
639 // Reflection support
640 bool is_overridden_in(Klass* k) const;
641
642 // JSR 292 support
643 bool is_method_handle_intrinsic() const; // MethodHandles::is_signature_polymorphic_intrinsic(intrinsic_id)
644 bool is_compiled_lambda_form() const; // intrinsic_id() == vmIntrinsics::_compiledLambdaForm
645 bool has_member_arg() const; // intrinsic_id() == vmIntrinsics::_linkToSpecial, etc.
646 static methodHandle make_method_handle_intrinsic(vmIntrinsics::ID iid, // _invokeBasic, _linkToVirtual
647 Symbol* signature, //anything at all
648 TRAPS);
649 static Klass* check_non_bcp_klass(Klass* klass);
650 // these operate only on invoke methods:
651 // presize interpreter frames for extra interpreter stack entries, if needed
652 // method handles want to be able to push a few extra values (e.g., a bound receiver), and
653 // invokedynamic sometimes needs to push a bootstrap method, call site, and arglist,
654 // all without checking for a stack overflow
655 static int extra_stack_entries() { return EnableInvokeDynamic ? 2 : 0; }
656 static int extra_stack_words(); // = extra_stack_entries() * Interpreter::stackElementSize()
657
658 // RedefineClasses() support:
659 bool is_old() const { return access_flags().is_old(); }
660 void set_is_old() { _access_flags.set_is_old(); }
661 bool is_obsolete() const { return access_flags().is_obsolete(); }
662 void set_is_obsolete() { _access_flags.set_is_obsolete(); }
663 bool on_stack() const { return access_flags().on_stack(); }
664 void set_on_stack(const bool value);
665
666 // see the definition in Method*.cpp for the gory details
667 bool should_not_be_cached() const;
668
669 // JVMTI Native method prefixing support:
670 bool is_prefixed_native() const { return access_flags().is_prefixed_native(); }
671 void set_is_prefixed_native() { _access_flags.set_is_prefixed_native(); }
672
673 // Rewriting support
674 static methodHandle clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
675 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS);
676
677 // jmethodID handling
678 // Because the useful life-span of a jmethodID cannot be determined,
679 // once created they are never reclaimed. The methods to which they refer,
680 // however, can be GC'ed away if the class is unloaded or if the method is
681 // made obsolete or deleted -- in these cases, the jmethodID
682 // refers to NULL (as is the case for any weak reference).
683 static jmethodID make_jmethod_id(ClassLoaderData* loader_data, Method* mh);
684 static void destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID mid);
685
686 // Use resolve_jmethod_id() in situations where the caller is expected
687 // to provide a valid jmethodID; the only sanity checks are in asserts;
688 // result guaranteed not to be NULL.
689 inline static Method* resolve_jmethod_id(jmethodID mid) {
690 assert(mid != NULL, "JNI method id should not be null");
691 return *((Method**)mid);
692 }
693
694 // Use checked_resolve_jmethod_id() in situations where the caller
695 // should provide a valid jmethodID, but might not. NULL is returned
696 // when the jmethodID does not refer to a valid method.
697 static Method* checked_resolve_jmethod_id(jmethodID mid);
698
699 static void change_method_associated_with_jmethod_id(jmethodID old_jmid_ptr, Method* new_method);
700 static bool is_method_id(jmethodID mid);
701
702 // Clear methods
703 static void clear_jmethod_ids(ClassLoaderData* loader_data);
704 static void print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
705
706 // Get this method's jmethodID -- allocate if it doesn't exist
707 jmethodID jmethod_id() { methodHandle this_h(this);
708 return InstanceKlass::get_jmethod_id(method_holder(), this_h); }
709
710 // Lookup the jmethodID for this method. Return NULL if not found.
711 // NOTE that this function can be called from a signal handler
712 // (see AsyncGetCallTrace support for Forte Analyzer) and this
713 // needs to be async-safe. No allocation should be done and
714 // so handles are not used to avoid deadlock.
715 jmethodID find_jmethod_id_or_null() { return method_holder()->jmethod_id_or_null(this); }
716
717 // JNI static invoke cached itable index accessors
718 int cached_itable_index() { return method_holder()->cached_itable_index(method_idnum()); }
719 void set_cached_itable_index(int index) { method_holder()->set_cached_itable_index(method_idnum(), index); }
720
721 // Support for inlining of intrinsic methods
722 vmIntrinsics::ID intrinsic_id() const { return (vmIntrinsics::ID) _intrinsic_id; }
723 void set_intrinsic_id(vmIntrinsics::ID id) { _intrinsic_id = (u1) id; }
724
725 // Helper routines for intrinsic_id() and vmIntrinsics::method().
726 void init_intrinsic_id(); // updates from _none if a match
727 static vmSymbols::SID klass_id_for_intrinsics(Klass* holder);
728
729 bool jfr_towrite() { return _jfr_towrite; }
730 void set_jfr_towrite(bool towrite) { _jfr_towrite = towrite; }
731
732 bool force_inline() { return _force_inline; }
733 void set_force_inline(bool x) { _force_inline = x; }
734 bool dont_inline() { return _dont_inline; }
735 void set_dont_inline(bool x) { _dont_inline = x; }
736 bool is_hidden() { return _hidden; }
737 void set_hidden(bool x) { _hidden = x; }
738 ConstMethod::MethodType method_type() const {
739 return _constMethod->method_type();
740 }
741 bool is_overpass() const { return method_type() == ConstMethod::OVERPASS; }
742
743 // On-stack replacement support
744 bool has_osr_nmethod(int level, bool match_level) {
745 return method_holder()->lookup_osr_nmethod(this, InvocationEntryBci, level, match_level) != NULL;
746 }
747
748 nmethod* lookup_osr_nmethod_for(int bci, int level, bool match_level) {
749 return method_holder()->lookup_osr_nmethod(this, bci, level, match_level);
750 }
751
752 // Inline cache support
753 void cleanup_inline_caches();
754
755 // Find if klass for method is loaded
756 bool is_klass_loaded_by_klass_index(int klass_index) const;
757 bool is_klass_loaded(int refinfo_index, bool must_be_resolved = false) const;
758
759 // Indicates whether compilation failed earlier for this method, or
760 // whether it is not compilable for another reason like having a
761 // breakpoint set in it.
762 bool is_not_compilable(int comp_level = CompLevel_any) const;
763 void set_not_compilable(int comp_level = CompLevel_all, bool report = true);
764 void set_not_compilable_quietly(int comp_level = CompLevel_all) {
765 set_not_compilable(comp_level, false);
766 }
767 bool is_not_osr_compilable(int comp_level = CompLevel_any) const;
768 void set_not_osr_compilable(int comp_level = CompLevel_all, bool report = true);
769 void set_not_osr_compilable_quietly(int comp_level = CompLevel_all) {
770 set_not_osr_compilable(comp_level, false);
771 }
772
773 private:
774 void print_made_not_compilable(int comp_level, bool is_osr, bool report);
775
776 public:
777 bool is_not_c1_compilable() const { return access_flags().is_not_c1_compilable(); }
778 void set_not_c1_compilable() { _access_flags.set_not_c1_compilable(); }
779 bool is_not_c2_compilable() const { return access_flags().is_not_c2_compilable(); }
780 void set_not_c2_compilable() { _access_flags.set_not_c2_compilable(); }
781
782 bool is_not_c1_osr_compilable() const { return is_not_c1_compilable(); } // don't waste an accessFlags bit
783 void set_not_c1_osr_compilable() { set_not_c1_compilable(); } // don't waste an accessFlags bit
784 bool is_not_c2_osr_compilable() const { return access_flags().is_not_c2_osr_compilable(); }
785 void set_not_c2_osr_compilable() { _access_flags.set_not_c2_osr_compilable(); }
786
787 // Background compilation support
788 bool queued_for_compilation() const { return access_flags().queued_for_compilation(); }
789 void set_queued_for_compilation() { _access_flags.set_queued_for_compilation(); }
790 void clear_queued_for_compilation() { _access_flags.clear_queued_for_compilation(); }
791
792 // Resolve all classes in signature, return 'true' if successful
793 static bool load_signature_classes(methodHandle m, TRAPS);
794
795 // Return if true if not all classes references in signature, including return type, has been loaded
796 static bool has_unloaded_classes_in_signature(methodHandle m, TRAPS);
797
798 // Printing
799 void print_short_name(outputStream* st = tty) /*PRODUCT_RETURN*/; // prints as klassname::methodname; Exposed so field engineers can debug VM
800 void print_name(outputStream* st = tty) PRODUCT_RETURN; // prints as "virtual void foo(int)"
801
802 // Helper routine used for method sorting
803 static void sort_methods(Array<Method*>* methods,
804 Array<AnnotationArray*>* methods_annotations,
805 Array<AnnotationArray*>* methods_parameter_annotations,
806 Array<AnnotationArray*>* methods_default_annotations,
807 Array<AnnotationArray*>* methods_type_annotations,
808 bool idempotent = false);
809
810 // Deallocation function for redefine classes or if an error occurs
811 void deallocate_contents(ClassLoaderData* loader_data);
812
813 // Printing
814 #ifndef PRODUCT
815 void print_on(outputStream* st) const;
816 #endif
817 void print_value_on(outputStream* st) const;
818
819 const char* internal_name() const { return "{method}"; }
820
821 // Check for valid method pointer
822 bool is_valid_method() const;
823
824 // Verify
825 void verify() { verify_on(tty); }
826 void verify_on(outputStream* st);
827
828 private:
829
830 // Inlined elements
831 address* native_function_addr() const { assert(is_native(), "must be native"); return (address*) (this+1); }
832 address* signature_handler_addr() const { return native_function_addr() + 1; }
833 };
834
835
836 // Utility class for compressing line number tables
837
838 class CompressedLineNumberWriteStream: public CompressedWriteStream {
839 private:
840 int _bci;
841 int _line;
842 public:
843 // Constructor
844 CompressedLineNumberWriteStream(int initial_size) : CompressedWriteStream(initial_size), _bci(0), _line(0) {}
845 CompressedLineNumberWriteStream(u_char* buffer, int initial_size) : CompressedWriteStream(buffer, initial_size), _bci(0), _line(0) {}
846
847 // Write (bci, line number) pair to stream
848 void write_pair_regular(int bci_delta, int line_delta);
849
850 inline void write_pair_inline(int bci, int line) {
851 int bci_delta = bci - _bci;
852 int line_delta = line - _line;
853 _bci = bci;
854 _line = line;
855 // Skip (0,0) deltas - they do not add information and conflict with terminator.
856 if (bci_delta == 0 && line_delta == 0) return;
857 // Check if bci is 5-bit and line number 3-bit unsigned.
858 if (((bci_delta & ~0x1F) == 0) && ((line_delta & ~0x7) == 0)) {
859 // Compress into single byte.
860 jubyte value = ((jubyte) bci_delta << 3) | (jubyte) line_delta;
861 // Check that value doesn't match escape character.
862 if (value != 0xFF) {
863 write_byte(value);
864 return;
865 }
866 }
867 write_pair_regular(bci_delta, line_delta);
868 }
869
870 // Windows AMD64 + Apr 2005 PSDK with /O2 generates bad code for write_pair.
871 // Disabling optimization doesn't work for methods in header files
872 // so we force it to call through the non-optimized version in the .cpp.
873 // It's gross, but it's the only way we can ensure that all callers are
874 // fixed. _MSC_VER is defined by the windows compiler
875 #if defined(_M_AMD64) && _MSC_VER >= 1400
876 void write_pair(int bci, int line);
877 #else
878 void write_pair(int bci, int line) { write_pair_inline(bci, line); }
879 #endif
880
881 // Write end-of-stream marker
882 void write_terminator() { write_byte(0); }
883 };
884
885
886 // Utility class for decompressing line number tables
887
888 class CompressedLineNumberReadStream: public CompressedReadStream {
889 private:
890 int _bci;
891 int _line;
892 public:
893 // Constructor
894 CompressedLineNumberReadStream(u_char* buffer);
895 // Read (bci, line number) pair from stream. Returns false at end-of-stream.
896 bool read_pair();
897 // Accessing bci and line number (after calling read_pair)
898 int bci() const { return _bci; }
899 int line() const { return _line; }
900 };
901
902
903 /// Fast Breakpoints.
904
905 // If this structure gets more complicated (because bpts get numerous),
906 // move it into its own header.
907
908 // There is presently no provision for concurrent access
909 // to breakpoint lists, which is only OK for JVMTI because
910 // breakpoints are written only at safepoints, and are read
911 // concurrently only outside of safepoints.
912
913 class BreakpointInfo : public CHeapObj<mtClass> {
914 friend class VMStructs;
915 private:
916 Bytecodes::Code _orig_bytecode;
917 int _bci;
918 u2 _name_index; // of method
919 u2 _signature_index; // of method
920 BreakpointInfo* _next; // simple storage allocation
921
922 public:
923 BreakpointInfo(Method* m, int bci);
924
925 // accessors
926 Bytecodes::Code orig_bytecode() { return _orig_bytecode; }
927 void set_orig_bytecode(Bytecodes::Code code) { _orig_bytecode = code; }
928 int bci() { return _bci; }
929
930 BreakpointInfo* next() const { return _next; }
931 void set_next(BreakpointInfo* n) { _next = n; }
932
933 // helps for searchers
934 bool match(const Method* m, int bci) {
935 return bci == _bci && match(m);
936 }
937
938 bool match(const Method* m) {
939 return _name_index == m->name_index() &&
940 _signature_index == m->signature_index();
941 }
942
943 void set(Method* method);
944 void clear(Method* method);
945 };
946
947 // Utility class for access exception handlers
948 class ExceptionTable : public StackObj {
949 private:
950 ExceptionTableElement* _table;
951 u2 _length;
952
953 public:
954 ExceptionTable(Method* m) {
955 if (m->has_exception_handler()) {
956 _table = m->exception_table_start();
957 _length = m->exception_table_length();
958 } else {
959 _table = NULL;
960 _length = 0;
961 }
962 }
963
964 int length() const {
965 return _length;
966 }
967
968 u2 start_pc(int idx) const {
969 assert(idx < _length, "out of bounds");
970 return _table[idx].start_pc;
971 }
972
973 void set_start_pc(int idx, u2 value) {
974 assert(idx < _length, "out of bounds");
975 _table[idx].start_pc = value;
976 }
977
978 u2 end_pc(int idx) const {
979 assert(idx < _length, "out of bounds");
980 return _table[idx].end_pc;
981 }
982
983 void set_end_pc(int idx, u2 value) {
984 assert(idx < _length, "out of bounds");
985 _table[idx].end_pc = value;
986 }
987
988 u2 handler_pc(int idx) const {
989 assert(idx < _length, "out of bounds");
990 return _table[idx].handler_pc;
991 }
992
993 void set_handler_pc(int idx, u2 value) {
994 assert(idx < _length, "out of bounds");
995 _table[idx].handler_pc = value;
996 }
997
998 u2 catch_type_index(int idx) const {
999 assert(idx < _length, "out of bounds");
1000 return _table[idx].catch_type_index;
1001 }
1002
1003 void set_catch_type_index(int idx, u2 value) {
1004 assert(idx < _length, "out of bounds");
1005 _table[idx].catch_type_index = value;
1006 }
1007 };
1008
1009 #endif // SHARE_VM_OOPS_METHODOOP_HPP