1 /*
2 * Copyright (c) 2000, 2013, 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 *
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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 *
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23 */
24
25 #ifndef SHARE_VM_OOPS_METHODDATAOOP_HPP
26 #define SHARE_VM_OOPS_METHODDATAOOP_HPP
27
28 #include "interpreter/bytecodes.hpp"
29 #include "memory/universe.hpp"
30 #include "oops/method.hpp"
31 #include "oops/oop.hpp"
32 #include "runtime/orderAccess.hpp"
33
34 class BytecodeStream;
35 class KlassSizeStats;
36
37 // The MethodData object collects counts and other profile information
38 // during zeroth-tier (interpretive) and first-tier execution.
39 // The profile is used later by compilation heuristics. Some heuristics
40 // enable use of aggressive (or "heroic") optimizations. An aggressive
41 // optimization often has a down-side, a corner case that it handles
42 // poorly, but which is thought to be rare. The profile provides
43 // evidence of this rarity for a given method or even BCI. It allows
44 // the compiler to back out of the optimization at places where it
45 // has historically been a poor choice. Other heuristics try to use
46 // specific information gathered about types observed at a given site.
47 //
48 // All data in the profile is approximate. It is expected to be accurate
49 // on the whole, but the system expects occasional inaccuraces, due to
50 // counter overflow, multiprocessor races during data collection, space
51 // limitations, missing MDO blocks, etc. Bad or missing data will degrade
52 // optimization quality but will not affect correctness. Also, each MDO
53 // is marked with its birth-date ("creation_mileage") which can be used
54 // to assess the quality ("maturity") of its data.
55 //
56 // Short (<32-bit) counters are designed to overflow to a known "saturated"
57 // state. Also, certain recorded per-BCI events are given one-bit counters
58 // which overflow to a saturated state which applied to all counters at
59 // that BCI. In other words, there is a small lattice which approximates
60 // the ideal of an infinite-precision counter for each event at each BCI,
61 // and the lattice quickly "bottoms out" in a state where all counters
62 // are taken to be indefinitely large.
63 //
64 // The reader will find many data races in profile gathering code, starting
65 // with invocation counter incrementation. None of these races harm correct
66 // execution of the compiled code.
67
68 // forward decl
69 class ProfileData;
70
71 // DataLayout
72 //
73 // Overlay for generic profiling data.
74 class DataLayout VALUE_OBJ_CLASS_SPEC {
75 private:
76 // Every data layout begins with a header. This header
77 // contains a tag, which is used to indicate the size/layout
78 // of the data, 4 bits of flags, which can be used in any way,
79 // 4 bits of trap history (none/one reason/many reasons),
80 // and a bci, which is used to tie this piece of data to a
81 // specific bci in the bytecodes.
82 union {
83 intptr_t _bits;
84 struct {
85 u1 _tag;
86 u1 _flags;
87 u2 _bci;
88 } _struct;
89 } _header;
90
91 // The data layout has an arbitrary number of cells, each sized
92 // to accomodate a pointer or an integer.
93 intptr_t _cells[1];
94
95 // Some types of data layouts need a length field.
96 static bool needs_array_len(u1 tag);
97
98 public:
99 enum {
100 counter_increment = 1
101 };
102
103 enum {
104 cell_size = sizeof(intptr_t)
105 };
106
107 // Tag values
108 enum {
109 no_tag,
110 bit_data_tag,
111 counter_data_tag,
112 jump_data_tag,
113 receiver_type_data_tag,
114 virtual_call_data_tag,
115 ret_data_tag,
116 branch_data_tag,
117 multi_branch_data_tag,
118 arg_info_data_tag
119 };
120
121 enum {
122 // The _struct._flags word is formatted as [trap_state:4 | flags:4].
123 // The trap state breaks down further as [recompile:1 | reason:3].
124 // This further breakdown is defined in deoptimization.cpp.
125 // See Deoptimization::trap_state_reason for an assert that
126 // trap_bits is big enough to hold reasons < Reason_RECORDED_LIMIT.
127 //
128 // The trap_state is collected only if ProfileTraps is true.
129 trap_bits = 1+3, // 3: enough to distinguish [0..Reason_RECORDED_LIMIT].
130 trap_shift = BitsPerByte - trap_bits,
131 trap_mask = right_n_bits(trap_bits),
132 trap_mask_in_place = (trap_mask << trap_shift),
133 flag_limit = trap_shift,
134 flag_mask = right_n_bits(flag_limit),
135 first_flag = 0
136 };
137
138 // Size computation
139 static int header_size_in_bytes() {
140 return cell_size;
141 }
142 static int header_size_in_cells() {
143 return 1;
144 }
145
146 static int compute_size_in_bytes(int cell_count) {
147 return header_size_in_bytes() + cell_count * cell_size;
148 }
149
150 // Initialization
151 void initialize(u1 tag, u2 bci, int cell_count);
152
153 // Accessors
154 u1 tag() {
155 return _header._struct._tag;
156 }
157
158 // Return a few bits of trap state. Range is [0..trap_mask].
159 // The state tells if traps with zero, one, or many reasons have occurred.
160 // It also tells whether zero or many recompilations have occurred.
161 // The associated trap histogram in the MDO itself tells whether
162 // traps are common or not. If a BCI shows that a trap X has
163 // occurred, and the MDO shows N occurrences of X, we make the
164 // simplifying assumption that all N occurrences can be blamed
165 // on that BCI.
166 int trap_state() {
167 return ((_header._struct._flags >> trap_shift) & trap_mask);
168 }
169
170 void set_trap_state(int new_state) {
171 assert(ProfileTraps, "used only under +ProfileTraps");
172 uint old_flags = (_header._struct._flags & flag_mask);
173 _header._struct._flags = (new_state << trap_shift) | old_flags;
174 }
175
176 u1 flags() {
177 return _header._struct._flags;
178 }
179
180 u2 bci() {
181 return _header._struct._bci;
182 }
183
184 void set_header(intptr_t value) {
185 _header._bits = value;
186 }
187 void release_set_header(intptr_t value) {
188 OrderAccess::release_store_ptr(&_header._bits, value);
189 }
190 intptr_t header() {
191 return _header._bits;
192 }
193 void set_cell_at(int index, intptr_t value) {
194 _cells[index] = value;
195 }
196 void release_set_cell_at(int index, intptr_t value) {
197 OrderAccess::release_store_ptr(&_cells[index], value);
198 }
199 intptr_t cell_at(int index) {
200 return _cells[index];
201 }
202
203 void set_flag_at(int flag_number) {
204 assert(flag_number < flag_limit, "oob");
205 _header._struct._flags |= (0x1 << flag_number);
206 }
207 bool flag_at(int flag_number) {
208 assert(flag_number < flag_limit, "oob");
209 return (_header._struct._flags & (0x1 << flag_number)) != 0;
210 }
211
212 // Low-level support for code generation.
213 static ByteSize header_offset() {
214 return byte_offset_of(DataLayout, _header);
215 }
216 static ByteSize tag_offset() {
217 return byte_offset_of(DataLayout, _header._struct._tag);
218 }
219 static ByteSize flags_offset() {
220 return byte_offset_of(DataLayout, _header._struct._flags);
221 }
222 static ByteSize bci_offset() {
223 return byte_offset_of(DataLayout, _header._struct._bci);
224 }
225 static ByteSize cell_offset(int index) {
226 return byte_offset_of(DataLayout, _cells) + in_ByteSize(index * cell_size);
227 }
228 // Return a value which, when or-ed as a byte into _flags, sets the flag.
229 static int flag_number_to_byte_constant(int flag_number) {
230 assert(0 <= flag_number && flag_number < flag_limit, "oob");
231 DataLayout temp; temp.set_header(0);
232 temp.set_flag_at(flag_number);
233 return temp._header._struct._flags;
234 }
235 // Return a value which, when or-ed as a word into _header, sets the flag.
236 static intptr_t flag_mask_to_header_mask(int byte_constant) {
237 DataLayout temp; temp.set_header(0);
238 temp._header._struct._flags = byte_constant;
239 return temp._header._bits;
240 }
241
242 ProfileData* data_in();
243
244 // GC support
245 void clean_weak_klass_links(BoolObjectClosure* cl);
246 };
247
248
249 // ProfileData class hierarchy
250 class ProfileData;
251 class BitData;
252 class CounterData;
253 class ReceiverTypeData;
254 class VirtualCallData;
255 class RetData;
256 class JumpData;
257 class BranchData;
258 class ArrayData;
259 class MultiBranchData;
260 class ArgInfoData;
261
262
263 // ProfileData
264 //
265 // A ProfileData object is created to refer to a section of profiling
266 // data in a structured way.
267 class ProfileData : public ResourceObj {
268 private:
269 #ifndef PRODUCT
270 enum {
271 tab_width_one = 16,
272 tab_width_two = 36
273 };
274 #endif // !PRODUCT
275
276 // This is a pointer to a section of profiling data.
277 DataLayout* _data;
278
279 protected:
280 DataLayout* data() { return _data; }
281
282 enum {
283 cell_size = DataLayout::cell_size
284 };
285
286 public:
287 // How many cells are in this?
288 virtual int cell_count() {
289 ShouldNotReachHere();
290 return -1;
291 }
292
293 // Return the size of this data.
294 int size_in_bytes() {
295 return DataLayout::compute_size_in_bytes(cell_count());
296 }
297
298 protected:
299 // Low-level accessors for underlying data
300 void set_intptr_at(int index, intptr_t value) {
301 assert(0 <= index && index < cell_count(), "oob");
302 data()->set_cell_at(index, value);
303 }
304 void release_set_intptr_at(int index, intptr_t value) {
305 assert(0 <= index && index < cell_count(), "oob");
306 data()->release_set_cell_at(index, value);
307 }
308 intptr_t intptr_at(int index) {
309 assert(0 <= index && index < cell_count(), "oob");
310 return data()->cell_at(index);
311 }
312 void set_uint_at(int index, uint value) {
313 set_intptr_at(index, (intptr_t) value);
314 }
315 void release_set_uint_at(int index, uint value) {
316 release_set_intptr_at(index, (intptr_t) value);
317 }
318 uint uint_at(int index) {
319 return (uint)intptr_at(index);
320 }
321 void set_int_at(int index, int value) {
322 set_intptr_at(index, (intptr_t) value);
323 }
324 void release_set_int_at(int index, int value) {
325 release_set_intptr_at(index, (intptr_t) value);
326 }
327 int int_at(int index) {
328 return (int)intptr_at(index);
329 }
330 int int_at_unchecked(int index) {
331 return (int)data()->cell_at(index);
332 }
333 void set_oop_at(int index, oop value) {
334 set_intptr_at(index, (intptr_t) value);
335 }
336 oop oop_at(int index) {
337 return (oop)intptr_at(index);
338 }
339
340 void set_flag_at(int flag_number) {
341 data()->set_flag_at(flag_number);
342 }
343 bool flag_at(int flag_number) {
344 return data()->flag_at(flag_number);
345 }
346
347 // two convenient imports for use by subclasses:
348 static ByteSize cell_offset(int index) {
349 return DataLayout::cell_offset(index);
350 }
351 static int flag_number_to_byte_constant(int flag_number) {
352 return DataLayout::flag_number_to_byte_constant(flag_number);
353 }
354
355 ProfileData(DataLayout* data) {
356 _data = data;
357 }
358
359 public:
360 // Constructor for invalid ProfileData.
361 ProfileData();
362
363 u2 bci() {
364 return data()->bci();
365 }
366
367 address dp() {
368 return (address)_data;
369 }
370
371 int trap_state() {
372 return data()->trap_state();
373 }
374 void set_trap_state(int new_state) {
375 data()->set_trap_state(new_state);
376 }
377
378 // Type checking
379 virtual bool is_BitData() { return false; }
380 virtual bool is_CounterData() { return false; }
381 virtual bool is_JumpData() { return false; }
382 virtual bool is_ReceiverTypeData(){ return false; }
383 virtual bool is_VirtualCallData() { return false; }
384 virtual bool is_RetData() { return false; }
385 virtual bool is_BranchData() { return false; }
386 virtual bool is_ArrayData() { return false; }
387 virtual bool is_MultiBranchData() { return false; }
388 virtual bool is_ArgInfoData() { return false; }
389
390
391 BitData* as_BitData() {
392 assert(is_BitData(), "wrong type");
393 return is_BitData() ? (BitData*) this : NULL;
394 }
395 CounterData* as_CounterData() {
396 assert(is_CounterData(), "wrong type");
397 return is_CounterData() ? (CounterData*) this : NULL;
398 }
399 JumpData* as_JumpData() {
400 assert(is_JumpData(), "wrong type");
401 return is_JumpData() ? (JumpData*) this : NULL;
402 }
403 ReceiverTypeData* as_ReceiverTypeData() {
404 assert(is_ReceiverTypeData(), "wrong type");
405 return is_ReceiverTypeData() ? (ReceiverTypeData*)this : NULL;
406 }
407 VirtualCallData* as_VirtualCallData() {
408 assert(is_VirtualCallData(), "wrong type");
409 return is_VirtualCallData() ? (VirtualCallData*)this : NULL;
410 }
411 RetData* as_RetData() {
412 assert(is_RetData(), "wrong type");
413 return is_RetData() ? (RetData*) this : NULL;
414 }
415 BranchData* as_BranchData() {
416 assert(is_BranchData(), "wrong type");
417 return is_BranchData() ? (BranchData*) this : NULL;
418 }
419 ArrayData* as_ArrayData() {
420 assert(is_ArrayData(), "wrong type");
421 return is_ArrayData() ? (ArrayData*) this : NULL;
422 }
423 MultiBranchData* as_MultiBranchData() {
424 assert(is_MultiBranchData(), "wrong type");
425 return is_MultiBranchData() ? (MultiBranchData*)this : NULL;
426 }
427 ArgInfoData* as_ArgInfoData() {
428 assert(is_ArgInfoData(), "wrong type");
429 return is_ArgInfoData() ? (ArgInfoData*)this : NULL;
430 }
431
432
433 // Subclass specific initialization
434 virtual void post_initialize(BytecodeStream* stream, MethodData* mdo) {}
435
436 // GC support
437 virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure) {}
438
439 // CI translation: ProfileData can represent both MethodDataOop data
440 // as well as CIMethodData data. This function is provided for translating
441 // an oop in a ProfileData to the ci equivalent. Generally speaking,
442 // most ProfileData don't require any translation, so we provide the null
443 // translation here, and the required translators are in the ci subclasses.
444 virtual void translate_from(ProfileData* data) {}
445
446 virtual void print_data_on(outputStream* st) {
447 ShouldNotReachHere();
448 }
449
450 #ifndef PRODUCT
451 void print_shared(outputStream* st, const char* name);
452 void tab(outputStream* st);
453 #endif
454 };
455
456 // BitData
457 //
458 // A BitData holds a flag or two in its header.
459 class BitData : public ProfileData {
460 protected:
461 enum {
462 // null_seen:
463 // saw a null operand (cast/aastore/instanceof)
464 null_seen_flag = DataLayout::first_flag + 0
465 };
466 enum { bit_cell_count = 0 }; // no additional data fields needed.
467 public:
468 BitData(DataLayout* layout) : ProfileData(layout) {
469 }
470
471 virtual bool is_BitData() { return true; }
472
473 static int static_cell_count() {
474 return bit_cell_count;
475 }
476
477 virtual int cell_count() {
478 return static_cell_count();
479 }
480
481 // Accessor
482
483 // The null_seen flag bit is specially known to the interpreter.
484 // Consulting it allows the compiler to avoid setting up null_check traps.
485 bool null_seen() { return flag_at(null_seen_flag); }
486 void set_null_seen() { set_flag_at(null_seen_flag); }
487
488
489 // Code generation support
490 static int null_seen_byte_constant() {
491 return flag_number_to_byte_constant(null_seen_flag);
492 }
493
494 static ByteSize bit_data_size() {
495 return cell_offset(bit_cell_count);
496 }
497
498 #ifndef PRODUCT
499 void print_data_on(outputStream* st);
500 #endif
501 };
502
503 // CounterData
504 //
505 // A CounterData corresponds to a simple counter.
506 class CounterData : public BitData {
507 protected:
508 enum {
509 count_off,
510 counter_cell_count
511 };
512 public:
513 CounterData(DataLayout* layout) : BitData(layout) {}
514
515 virtual bool is_CounterData() { return true; }
516
517 static int static_cell_count() {
518 return counter_cell_count;
519 }
520
521 virtual int cell_count() {
522 return static_cell_count();
523 }
524
525 // Direct accessor
526 uint count() {
527 return uint_at(count_off);
528 }
529
530 // Code generation support
531 static ByteSize count_offset() {
532 return cell_offset(count_off);
533 }
534 static ByteSize counter_data_size() {
535 return cell_offset(counter_cell_count);
536 }
537
538 void set_count(uint count) {
539 set_uint_at(count_off, count);
540 }
541
542 #ifndef PRODUCT
543 void print_data_on(outputStream* st);
544 #endif
545 };
546
547 // JumpData
548 //
549 // A JumpData is used to access profiling information for a direct
550 // branch. It is a counter, used for counting the number of branches,
551 // plus a data displacement, used for realigning the data pointer to
552 // the corresponding target bci.
553 class JumpData : public ProfileData {
554 protected:
555 enum {
556 taken_off_set,
557 displacement_off_set,
558 jump_cell_count
559 };
560
561 void set_displacement(int displacement) {
562 set_int_at(displacement_off_set, displacement);
563 }
564
565 public:
566 JumpData(DataLayout* layout) : ProfileData(layout) {
567 assert(layout->tag() == DataLayout::jump_data_tag ||
568 layout->tag() == DataLayout::branch_data_tag, "wrong type");
569 }
570
571 virtual bool is_JumpData() { return true; }
572
573 static int static_cell_count() {
574 return jump_cell_count;
575 }
576
577 virtual int cell_count() {
578 return static_cell_count();
579 }
580
581 // Direct accessor
582 uint taken() {
583 return uint_at(taken_off_set);
584 }
585
586 void set_taken(uint cnt) {
587 set_uint_at(taken_off_set, cnt);
588 }
589
590 // Saturating counter
591 uint inc_taken() {
592 uint cnt = taken() + 1;
593 // Did we wrap? Will compiler screw us??
594 if (cnt == 0) cnt--;
595 set_uint_at(taken_off_set, cnt);
596 return cnt;
597 }
598
599 int displacement() {
600 return int_at(displacement_off_set);
601 }
602
603 // Code generation support
604 static ByteSize taken_offset() {
605 return cell_offset(taken_off_set);
606 }
607
608 static ByteSize displacement_offset() {
609 return cell_offset(displacement_off_set);
610 }
611
612 // Specific initialization.
613 void post_initialize(BytecodeStream* stream, MethodData* mdo);
614
615 #ifndef PRODUCT
616 void print_data_on(outputStream* st);
617 #endif
618 };
619
620 // ReceiverTypeData
621 //
622 // A ReceiverTypeData is used to access profiling information about a
623 // dynamic type check. It consists of a counter which counts the total times
624 // that the check is reached, and a series of (Klass*, count) pairs
625 // which are used to store a type profile for the receiver of the check.
626 class ReceiverTypeData : public CounterData {
627 protected:
628 enum {
629 receiver0_offset = counter_cell_count,
630 count0_offset,
631 receiver_type_row_cell_count = (count0_offset + 1) - receiver0_offset
632 };
633
634 public:
635 ReceiverTypeData(DataLayout* layout) : CounterData(layout) {
636 assert(layout->tag() == DataLayout::receiver_type_data_tag ||
637 layout->tag() == DataLayout::virtual_call_data_tag, "wrong type");
638 }
639
640 virtual bool is_ReceiverTypeData() { return true; }
641
642 static int static_cell_count() {
643 return counter_cell_count + (uint) TypeProfileWidth * receiver_type_row_cell_count;
644 }
645
646 virtual int cell_count() {
647 return static_cell_count();
648 }
649
650 // Direct accessors
651 static uint row_limit() {
652 return TypeProfileWidth;
653 }
654 static int receiver_cell_index(uint row) {
655 return receiver0_offset + row * receiver_type_row_cell_count;
656 }
657 static int receiver_count_cell_index(uint row) {
658 return count0_offset + row * receiver_type_row_cell_count;
659 }
660
661 Klass* receiver(uint row) {
662 assert(row < row_limit(), "oob");
663
664 Klass* recv = (Klass*)intptr_at(receiver_cell_index(row));
665 assert(recv == NULL || recv->is_klass(), "wrong type");
666 return recv;
667 }
668
669 void set_receiver(uint row, Klass* k) {
670 assert((uint)row < row_limit(), "oob");
671 set_intptr_at(receiver_cell_index(row), (uintptr_t)k);
672 }
673
674 uint receiver_count(uint row) {
675 assert(row < row_limit(), "oob");
676 return uint_at(receiver_count_cell_index(row));
677 }
678
679 void set_receiver_count(uint row, uint count) {
680 assert(row < row_limit(), "oob");
681 set_uint_at(receiver_count_cell_index(row), count);
682 }
683
684 void clear_row(uint row) {
685 assert(row < row_limit(), "oob");
686 // Clear total count - indicator of polymorphic call site.
687 // The site may look like as monomorphic after that but
688 // it allow to have more accurate profiling information because
689 // there was execution phase change since klasses were unloaded.
690 // If the site is still polymorphic then MDO will be updated
691 // to reflect it. But it could be the case that the site becomes
692 // only bimorphic. Then keeping total count not 0 will be wrong.
693 // Even if we use monomorphic (when it is not) for compilation
694 // we will only have trap, deoptimization and recompile again
695 // with updated MDO after executing method in Interpreter.
696 // An additional receiver will be recorded in the cleaned row
697 // during next call execution.
698 //
699 // Note: our profiling logic works with empty rows in any slot.
700 // We do sorting a profiling info (ciCallProfile) for compilation.
701 //
702 set_count(0);
703 set_receiver(row, NULL);
704 set_receiver_count(row, 0);
705 }
706
707 // Code generation support
708 static ByteSize receiver_offset(uint row) {
709 return cell_offset(receiver_cell_index(row));
710 }
711 static ByteSize receiver_count_offset(uint row) {
712 return cell_offset(receiver_count_cell_index(row));
713 }
714 static ByteSize receiver_type_data_size() {
715 return cell_offset(static_cell_count());
716 }
717
718 // GC support
719 virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure);
720
721 #ifndef PRODUCT
722 void print_receiver_data_on(outputStream* st);
723 void print_data_on(outputStream* st);
724 #endif
725 };
726
727 // VirtualCallData
728 //
729 // A VirtualCallData is used to access profiling information about a
730 // virtual call. For now, it has nothing more than a ReceiverTypeData.
731 class VirtualCallData : public ReceiverTypeData {
732 public:
733 VirtualCallData(DataLayout* layout) : ReceiverTypeData(layout) {
734 assert(layout->tag() == DataLayout::virtual_call_data_tag, "wrong type");
735 }
736
737 virtual bool is_VirtualCallData() { return true; }
738
739 static int static_cell_count() {
740 // At this point we could add more profile state, e.g., for arguments.
741 // But for now it's the same size as the base record type.
742 return ReceiverTypeData::static_cell_count();
743 }
744
745 virtual int cell_count() {
746 return static_cell_count();
747 }
748
749 // Direct accessors
750 static ByteSize virtual_call_data_size() {
751 return cell_offset(static_cell_count());
752 }
753
754 #ifndef PRODUCT
755 void print_data_on(outputStream* st);
756 #endif
757 };
758
759 // RetData
760 //
761 // A RetData is used to access profiling information for a ret bytecode.
762 // It is composed of a count of the number of times that the ret has
763 // been executed, followed by a series of triples of the form
764 // (bci, count, di) which count the number of times that some bci was the
765 // target of the ret and cache a corresponding data displacement.
766 class RetData : public CounterData {
767 protected:
768 enum {
769 bci0_offset = counter_cell_count,
770 count0_offset,
771 displacement0_offset,
772 ret_row_cell_count = (displacement0_offset + 1) - bci0_offset
773 };
774
775 void set_bci(uint row, int bci) {
776 assert((uint)row < row_limit(), "oob");
777 set_int_at(bci0_offset + row * ret_row_cell_count, bci);
778 }
779 void release_set_bci(uint row, int bci) {
780 assert((uint)row < row_limit(), "oob");
781 // 'release' when setting the bci acts as a valid flag for other
782 // threads wrt bci_count and bci_displacement.
783 release_set_int_at(bci0_offset + row * ret_row_cell_count, bci);
784 }
785 void set_bci_count(uint row, uint count) {
786 assert((uint)row < row_limit(), "oob");
787 set_uint_at(count0_offset + row * ret_row_cell_count, count);
788 }
789 void set_bci_displacement(uint row, int disp) {
790 set_int_at(displacement0_offset + row * ret_row_cell_count, disp);
791 }
792
793 public:
794 RetData(DataLayout* layout) : CounterData(layout) {
795 assert(layout->tag() == DataLayout::ret_data_tag, "wrong type");
796 }
797
798 virtual bool is_RetData() { return true; }
799
800 enum {
801 no_bci = -1 // value of bci when bci1/2 are not in use.
802 };
803
804 static int static_cell_count() {
805 return counter_cell_count + (uint) BciProfileWidth * ret_row_cell_count;
806 }
807
808 virtual int cell_count() {
809 return static_cell_count();
810 }
811
812 static uint row_limit() {
813 return BciProfileWidth;
814 }
815 static int bci_cell_index(uint row) {
816 return bci0_offset + row * ret_row_cell_count;
817 }
818 static int bci_count_cell_index(uint row) {
819 return count0_offset + row * ret_row_cell_count;
820 }
821 static int bci_displacement_cell_index(uint row) {
822 return displacement0_offset + row * ret_row_cell_count;
823 }
824
825 // Direct accessors
826 int bci(uint row) {
827 return int_at(bci_cell_index(row));
828 }
829 uint bci_count(uint row) {
830 return uint_at(bci_count_cell_index(row));
831 }
832 int bci_displacement(uint row) {
833 return int_at(bci_displacement_cell_index(row));
834 }
835
836 // Interpreter Runtime support
837 address fixup_ret(int return_bci, MethodData* mdo);
838
839 // Code generation support
840 static ByteSize bci_offset(uint row) {
841 return cell_offset(bci_cell_index(row));
842 }
843 static ByteSize bci_count_offset(uint row) {
844 return cell_offset(bci_count_cell_index(row));
845 }
846 static ByteSize bci_displacement_offset(uint row) {
847 return cell_offset(bci_displacement_cell_index(row));
848 }
849
850 // Specific initialization.
851 void post_initialize(BytecodeStream* stream, MethodData* mdo);
852
853 #ifndef PRODUCT
854 void print_data_on(outputStream* st);
855 #endif
856 };
857
858 // BranchData
859 //
860 // A BranchData is used to access profiling data for a two-way branch.
861 // It consists of taken and not_taken counts as well as a data displacement
862 // for the taken case.
863 class BranchData : public JumpData {
864 protected:
865 enum {
866 not_taken_off_set = jump_cell_count,
867 branch_cell_count
868 };
869
870 void set_displacement(int displacement) {
871 set_int_at(displacement_off_set, displacement);
872 }
873
874 public:
875 BranchData(DataLayout* layout) : JumpData(layout) {
876 assert(layout->tag() == DataLayout::branch_data_tag, "wrong type");
877 }
878
879 virtual bool is_BranchData() { return true; }
880
881 static int static_cell_count() {
882 return branch_cell_count;
883 }
884
885 virtual int cell_count() {
886 return static_cell_count();
887 }
888
889 // Direct accessor
890 uint not_taken() {
891 return uint_at(not_taken_off_set);
892 }
893
894 void set_not_taken(uint cnt) {
895 set_uint_at(not_taken_off_set, cnt);
896 }
897
898 uint inc_not_taken() {
899 uint cnt = not_taken() + 1;
900 // Did we wrap? Will compiler screw us??
901 if (cnt == 0) cnt--;
902 set_uint_at(not_taken_off_set, cnt);
903 return cnt;
904 }
905
906 // Code generation support
907 static ByteSize not_taken_offset() {
908 return cell_offset(not_taken_off_set);
909 }
910 static ByteSize branch_data_size() {
911 return cell_offset(branch_cell_count);
912 }
913
914 // Specific initialization.
915 void post_initialize(BytecodeStream* stream, MethodData* mdo);
916
917 #ifndef PRODUCT
918 void print_data_on(outputStream* st);
919 #endif
920 };
921
922 // ArrayData
923 //
924 // A ArrayData is a base class for accessing profiling data which does
925 // not have a statically known size. It consists of an array length
926 // and an array start.
927 class ArrayData : public ProfileData {
928 protected:
929 friend class DataLayout;
930
931 enum {
932 array_len_off_set,
933 array_start_off_set
934 };
935
936 uint array_uint_at(int index) {
937 int aindex = index + array_start_off_set;
938 return uint_at(aindex);
939 }
940 int array_int_at(int index) {
941 int aindex = index + array_start_off_set;
942 return int_at(aindex);
943 }
944 oop array_oop_at(int index) {
945 int aindex = index + array_start_off_set;
946 return oop_at(aindex);
947 }
948 void array_set_int_at(int index, int value) {
949 int aindex = index + array_start_off_set;
950 set_int_at(aindex, value);
951 }
952
953 // Code generation support for subclasses.
954 static ByteSize array_element_offset(int index) {
955 return cell_offset(array_start_off_set + index);
956 }
957
958 public:
959 ArrayData(DataLayout* layout) : ProfileData(layout) {}
960
961 virtual bool is_ArrayData() { return true; }
962
963 static int static_cell_count() {
964 return -1;
965 }
966
967 int array_len() {
968 return int_at_unchecked(array_len_off_set);
969 }
970
971 virtual int cell_count() {
972 return array_len() + 1;
973 }
974
975 // Code generation support
976 static ByteSize array_len_offset() {
977 return cell_offset(array_len_off_set);
978 }
979 static ByteSize array_start_offset() {
980 return cell_offset(array_start_off_set);
981 }
982 };
983
984 // MultiBranchData
985 //
986 // A MultiBranchData is used to access profiling information for
987 // a multi-way branch (*switch bytecodes). It consists of a series
988 // of (count, displacement) pairs, which count the number of times each
989 // case was taken and specify the data displacment for each branch target.
990 class MultiBranchData : public ArrayData {
991 protected:
992 enum {
993 default_count_off_set,
994 default_disaplacement_off_set,
995 case_array_start
996 };
997 enum {
998 relative_count_off_set,
999 relative_displacement_off_set,
1000 per_case_cell_count
1001 };
1002
1003 void set_default_displacement(int displacement) {
1004 array_set_int_at(default_disaplacement_off_set, displacement);
1005 }
1006 void set_displacement_at(int index, int displacement) {
1007 array_set_int_at(case_array_start +
1008 index * per_case_cell_count +
1009 relative_displacement_off_set,
1010 displacement);
1011 }
1012
1013 public:
1014 MultiBranchData(DataLayout* layout) : ArrayData(layout) {
1015 assert(layout->tag() == DataLayout::multi_branch_data_tag, "wrong type");
1016 }
1017
1018 virtual bool is_MultiBranchData() { return true; }
1019
1020 static int compute_cell_count(BytecodeStream* stream);
1021
1022 int number_of_cases() {
1023 int alen = array_len() - 2; // get rid of default case here.
1024 assert(alen % per_case_cell_count == 0, "must be even");
1025 return (alen / per_case_cell_count);
1026 }
1027
1028 uint default_count() {
1029 return array_uint_at(default_count_off_set);
1030 }
1031 int default_displacement() {
1032 return array_int_at(default_disaplacement_off_set);
1033 }
1034
1035 uint count_at(int index) {
1036 return array_uint_at(case_array_start +
1037 index * per_case_cell_count +
1038 relative_count_off_set);
1039 }
1040 int displacement_at(int index) {
1041 return array_int_at(case_array_start +
1042 index * per_case_cell_count +
1043 relative_displacement_off_set);
1044 }
1045
1046 // Code generation support
1047 static ByteSize default_count_offset() {
1048 return array_element_offset(default_count_off_set);
1049 }
1050 static ByteSize default_displacement_offset() {
1051 return array_element_offset(default_disaplacement_off_set);
1052 }
1053 static ByteSize case_count_offset(int index) {
1054 return case_array_offset() +
1055 (per_case_size() * index) +
1056 relative_count_offset();
1057 }
1058 static ByteSize case_array_offset() {
1059 return array_element_offset(case_array_start);
1060 }
1061 static ByteSize per_case_size() {
1062 return in_ByteSize(per_case_cell_count) * cell_size;
1063 }
1064 static ByteSize relative_count_offset() {
1065 return in_ByteSize(relative_count_off_set) * cell_size;
1066 }
1067 static ByteSize relative_displacement_offset() {
1068 return in_ByteSize(relative_displacement_off_set) * cell_size;
1069 }
1070
1071 // Specific initialization.
1072 void post_initialize(BytecodeStream* stream, MethodData* mdo);
1073
1074 #ifndef PRODUCT
1075 void print_data_on(outputStream* st);
1076 #endif
1077 };
1078
1079 class ArgInfoData : public ArrayData {
1080
1081 public:
1082 ArgInfoData(DataLayout* layout) : ArrayData(layout) {
1083 assert(layout->tag() == DataLayout::arg_info_data_tag, "wrong type");
1084 }
1085
1086 virtual bool is_ArgInfoData() { return true; }
1087
1088
1089 int number_of_args() {
1090 return array_len();
1091 }
1092
1093 uint arg_modified(int arg) {
1094 return array_uint_at(arg);
1095 }
1096
1097 void set_arg_modified(int arg, uint val) {
1098 array_set_int_at(arg, val);
1099 }
1100
1101 #ifndef PRODUCT
1102 void print_data_on(outputStream* st);
1103 #endif
1104 };
1105
1106 // MethodData*
1107 //
1108 // A MethodData* holds information which has been collected about
1109 // a method. Its layout looks like this:
1110 //
1111 // -----------------------------
1112 // | header |
1113 // | klass |
1114 // -----------------------------
1115 // | method |
1116 // | size of the MethodData* |
1117 // -----------------------------
1118 // | Data entries... |
1119 // | (variable size) |
1120 // | |
1121 // . .
1122 // . .
1123 // . .
1124 // | |
1125 // -----------------------------
1126 //
1127 // The data entry area is a heterogeneous array of DataLayouts. Each
1128 // DataLayout in the array corresponds to a specific bytecode in the
1129 // method. The entries in the array are sorted by the corresponding
1130 // bytecode. Access to the data is via resource-allocated ProfileData,
1131 // which point to the underlying blocks of DataLayout structures.
1132 //
1133 // During interpretation, if profiling in enabled, the interpreter
1134 // maintains a method data pointer (mdp), which points at the entry
1135 // in the array corresponding to the current bci. In the course of
1136 // intepretation, when a bytecode is encountered that has profile data
1137 // associated with it, the entry pointed to by mdp is updated, then the
1138 // mdp is adjusted to point to the next appropriate DataLayout. If mdp
1139 // is NULL to begin with, the interpreter assumes that the current method
1140 // is not (yet) being profiled.
1141 //
1142 // In MethodData* parlance, "dp" is a "data pointer", the actual address
1143 // of a DataLayout element. A "di" is a "data index", the offset in bytes
1144 // from the base of the data entry array. A "displacement" is the byte offset
1145 // in certain ProfileData objects that indicate the amount the mdp must be
1146 // adjusted in the event of a change in control flow.
1147 //
1148
1149 class MethodData : public Metadata {
1150 friend class VMStructs;
1151 private:
1152 friend class ProfileData;
1153
1154 // Back pointer to the Method*
1155 Method* _method;
1156
1157 // Size of this oop in bytes
1158 int _size;
1159
1160 // Cached hint for bci_to_dp and bci_to_data
1161 int _hint_di;
1162
1163 MethodData(methodHandle method, int size, TRAPS);
1164 public:
1165 static MethodData* allocate(ClassLoaderData* loader_data, methodHandle method, TRAPS);
1166 MethodData() {}; // For ciMethodData
1167
1168 bool is_methodData() const volatile { return true; }
1169
1170 // Whole-method sticky bits and flags
1171 enum {
1172 _trap_hist_limit = 17, // decoupled from Deoptimization::Reason_LIMIT
1173 _trap_hist_mask = max_jubyte,
1174 _extra_data_count = 4 // extra DataLayout headers, for trap history
1175 }; // Public flag values
1176 private:
1177 uint _nof_decompiles; // count of all nmethod removals
1178 uint _nof_overflow_recompiles; // recompile count, excluding recomp. bits
1179 uint _nof_overflow_traps; // trap count, excluding _trap_hist
1180 union {
1181 intptr_t _align;
1182 u1 _array[_trap_hist_limit];
1183 } _trap_hist;
1184
1185 // Support for interprocedural escape analysis, from Thomas Kotzmann.
1186 intx _eflags; // flags on escape information
1187 intx _arg_local; // bit set of non-escaping arguments
1188 intx _arg_stack; // bit set of stack-allocatable arguments
1189 intx _arg_returned; // bit set of returned arguments
1190
1191 int _creation_mileage; // method mileage at MDO creation
1192
1193 // How many invocations has this MDO seen?
1194 // These counters are used to determine the exact age of MDO.
1195 // We need those because in tiered a method can be concurrently
1196 // executed at different levels.
1197 InvocationCounter _invocation_counter;
1198 // Same for backedges.
1199 InvocationCounter _backedge_counter;
1200 // Counter values at the time profiling started.
1201 int _invocation_counter_start;
1202 int _backedge_counter_start;
1203 // Number of loops and blocks is computed when compiling the first
1204 // time with C1. It is used to determine if method is trivial.
1205 short _num_loops;
1206 short _num_blocks;
1207 // Highest compile level this method has ever seen.
1208 u1 _highest_comp_level;
1209 // Same for OSR level
1210 u1 _highest_osr_comp_level;
1211 // Does this method contain anything worth profiling?
1212 bool _would_profile;
1213
1214 // Size of _data array in bytes. (Excludes header and extra_data fields.)
1215 int _data_size;
1216
1217 // Beginning of the data entries
1218 intptr_t _data[1];
1219
1220 // Helper for size computation
1221 static int compute_data_size(BytecodeStream* stream);
1222 static int bytecode_cell_count(Bytecodes::Code code);
1223 enum { no_profile_data = -1, variable_cell_count = -2 };
1224
1225 // Helper for initialization
1226 DataLayout* data_layout_at(int data_index) const {
1227 assert(data_index % sizeof(intptr_t) == 0, "unaligned");
1228 return (DataLayout*) (((address)_data) + data_index);
1229 }
1230
1231 // Initialize an individual data segment. Returns the size of
1232 // the segment in bytes.
1233 int initialize_data(BytecodeStream* stream, int data_index);
1234
1235 // Helper for data_at
1236 DataLayout* limit_data_position() const {
1237 return (DataLayout*)((address)data_base() + _data_size);
1238 }
1239 bool out_of_bounds(int data_index) const {
1240 return data_index >= data_size();
1241 }
1242
1243 // Give each of the data entries a chance to perform specific
1244 // data initialization.
1245 void post_initialize(BytecodeStream* stream);
1246
1247 // hint accessors
1248 int hint_di() const { return _hint_di; }
1249 void set_hint_di(int di) {
1250 assert(!out_of_bounds(di), "hint_di out of bounds");
1251 _hint_di = di;
1252 }
1253 ProfileData* data_before(int bci) {
1254 // avoid SEGV on this edge case
1255 if (data_size() == 0)
1256 return NULL;
1257 int hint = hint_di();
1258 if (data_layout_at(hint)->bci() <= bci)
1259 return data_at(hint);
1260 return first_data();
1261 }
1262
1263 // What is the index of the first data entry?
1264 int first_di() const { return 0; }
1265
1266 // Find or create an extra ProfileData:
1267 ProfileData* bci_to_extra_data(int bci, bool create_if_missing);
1268
1269 // return the argument info cell
1270 ArgInfoData *arg_info();
1271
1272 public:
1273 static int header_size() {
1274 return sizeof(MethodData)/wordSize;
1275 }
1276
1277 // Compute the size of a MethodData* before it is created.
1278 static int compute_allocation_size_in_bytes(methodHandle method);
1279 static int compute_allocation_size_in_words(methodHandle method);
1280 static int compute_extra_data_count(int data_size, int empty_bc_count);
1281
1282 // Determine if a given bytecode can have profile information.
1283 static bool bytecode_has_profile(Bytecodes::Code code) {
1284 return bytecode_cell_count(code) != no_profile_data;
1285 }
1286
1287 // reset into original state
1288 void init();
1289
1290 // My size
1291 int size_in_bytes() const { return _size; }
1292 int size() const { return align_object_size(align_size_up(_size, BytesPerWord)/BytesPerWord); }
1293 #if INCLUDE_SERVICES
1294 void collect_statistics(KlassSizeStats *sz) const;
1295 #endif
1296
1297 int creation_mileage() const { return _creation_mileage; }
1298 void set_creation_mileage(int x) { _creation_mileage = x; }
1299
1300 int invocation_count() {
1301 if (invocation_counter()->carry()) {
1302 return InvocationCounter::count_limit;
1303 }
1304 return invocation_counter()->count();
1305 }
1306 int backedge_count() {
1307 if (backedge_counter()->carry()) {
1308 return InvocationCounter::count_limit;
1309 }
1310 return backedge_counter()->count();
1311 }
1312
1313 int invocation_count_start() {
1314 if (invocation_counter()->carry()) {
1315 return 0;
1316 }
1317 return _invocation_counter_start;
1318 }
1319
1320 int backedge_count_start() {
1321 if (backedge_counter()->carry()) {
1322 return 0;
1323 }
1324 return _backedge_counter_start;
1325 }
1326
1327 int invocation_count_delta() { return invocation_count() - invocation_count_start(); }
1328 int backedge_count_delta() { return backedge_count() - backedge_count_start(); }
1329
1330 void reset_start_counters() {
1331 _invocation_counter_start = invocation_count();
1332 _backedge_counter_start = backedge_count();
1333 }
1334
1335 InvocationCounter* invocation_counter() { return &_invocation_counter; }
1336 InvocationCounter* backedge_counter() { return &_backedge_counter; }
1337
1338 void set_would_profile(bool p) { _would_profile = p; }
1339 bool would_profile() const { return _would_profile; }
1340
1341 int highest_comp_level() { return _highest_comp_level; }
1342 void set_highest_comp_level(int level) { _highest_comp_level = level; }
1343 int highest_osr_comp_level() { return _highest_osr_comp_level; }
1344 void set_highest_osr_comp_level(int level) { _highest_osr_comp_level = level; }
1345
1346 int num_loops() const { return _num_loops; }
1347 void set_num_loops(int n) { _num_loops = n; }
1348 int num_blocks() const { return _num_blocks; }
1349 void set_num_blocks(int n) { _num_blocks = n; }
1350
1351 bool is_mature() const; // consult mileage and ProfileMaturityPercentage
1352 static int mileage_of(Method* m);
1353
1354 // Support for interprocedural escape analysis, from Thomas Kotzmann.
1355 enum EscapeFlag {
1356 estimated = 1 << 0,
1357 return_local = 1 << 1,
1358 return_allocated = 1 << 2,
1359 allocated_escapes = 1 << 3,
1360 unknown_modified = 1 << 4
1361 };
1362
1363 intx eflags() { return _eflags; }
1364 intx arg_local() { return _arg_local; }
1365 intx arg_stack() { return _arg_stack; }
1366 intx arg_returned() { return _arg_returned; }
1367 uint arg_modified(int a) { ArgInfoData *aid = arg_info();
1368 assert(aid != NULL, "arg_info must be not null");
1369 assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
1370 return aid->arg_modified(a); }
1371
1372 void set_eflags(intx v) { _eflags = v; }
1373 void set_arg_local(intx v) { _arg_local = v; }
1374 void set_arg_stack(intx v) { _arg_stack = v; }
1375 void set_arg_returned(intx v) { _arg_returned = v; }
1376 void set_arg_modified(int a, uint v) { ArgInfoData *aid = arg_info();
1377 assert(aid != NULL, "arg_info must be not null");
1378 assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
1379 aid->set_arg_modified(a, v); }
1380
1381 void clear_escape_info() { _eflags = _arg_local = _arg_stack = _arg_returned = 0; }
1382
1383 // Location and size of data area
1384 address data_base() const {
1385 return (address) _data;
1386 }
1387 int data_size() const {
1388 return _data_size;
1389 }
1390
1391 // Accessors
1392 Method* method() const { return _method; }
1393
1394 // Get the data at an arbitrary (sort of) data index.
1395 ProfileData* data_at(int data_index) const;
1396
1397 // Walk through the data in order.
1398 ProfileData* first_data() const { return data_at(first_di()); }
1399 ProfileData* next_data(ProfileData* current) const;
1400 bool is_valid(ProfileData* current) const { return current != NULL; }
1401
1402 // Convert a dp (data pointer) to a di (data index).
1403 int dp_to_di(address dp) const {
1404 return dp - ((address)_data);
1405 }
1406
1407 address di_to_dp(int di) {
1408 return (address)data_layout_at(di);
1409 }
1410
1411 // bci to di/dp conversion.
1412 address bci_to_dp(int bci);
1413 int bci_to_di(int bci) {
1414 return dp_to_di(bci_to_dp(bci));
1415 }
1416
1417 // Get the data at an arbitrary bci, or NULL if there is none.
1418 ProfileData* bci_to_data(int bci);
1419
1420 // Same, but try to create an extra_data record if one is needed:
1421 ProfileData* allocate_bci_to_data(int bci) {
1422 ProfileData* data = bci_to_data(bci);
1423 return (data != NULL) ? data : bci_to_extra_data(bci, true);
1424 }
1425
1426 // Add a handful of extra data records, for trap tracking.
1427 DataLayout* extra_data_base() const { return limit_data_position(); }
1428 DataLayout* extra_data_limit() const { return (DataLayout*)((address)this + size_in_bytes()); }
1429 int extra_data_size() const { return (address)extra_data_limit()
1430 - (address)extra_data_base(); }
1431 static DataLayout* next_extra(DataLayout* dp) { return (DataLayout*)((address)dp + in_bytes(DataLayout::cell_offset(0))); }
1432
1433 // Return (uint)-1 for overflow.
1434 uint trap_count(int reason) const {
1435 assert((uint)reason < _trap_hist_limit, "oob");
1436 return (int)((_trap_hist._array[reason]+1) & _trap_hist_mask) - 1;
1437 }
1438 // For loops:
1439 static uint trap_reason_limit() { return _trap_hist_limit; }
1440 static uint trap_count_limit() { return _trap_hist_mask; }
1441 uint inc_trap_count(int reason) {
1442 // Count another trap, anywhere in this method.
1443 assert(reason >= 0, "must be single trap");
1444 if ((uint)reason < _trap_hist_limit) {
1445 uint cnt1 = 1 + _trap_hist._array[reason];
1446 if ((cnt1 & _trap_hist_mask) != 0) { // if no counter overflow...
1447 _trap_hist._array[reason] = cnt1;
1448 return cnt1;
1449 } else {
1450 return _trap_hist_mask + (++_nof_overflow_traps);
1451 }
1452 } else {
1453 // Could not represent the count in the histogram.
1454 return (++_nof_overflow_traps);
1455 }
1456 }
1457
1458 uint overflow_trap_count() const {
1459 return _nof_overflow_traps;
1460 }
1461 uint overflow_recompile_count() const {
1462 return _nof_overflow_recompiles;
1463 }
1464 void inc_overflow_recompile_count() {
1465 _nof_overflow_recompiles += 1;
1466 }
1467 uint decompile_count() const {
1468 return _nof_decompiles;
1469 }
1470 void inc_decompile_count() {
1471 _nof_decompiles += 1;
1472 if (decompile_count() > (uint)PerMethodRecompilationCutoff) {
1473 method()->set_not_compilable(CompLevel_full_optimization, true, "decompile_count > PerMethodRecompilationCutoff");
1474 }
1475 }
1476
1477 // Support for code generation
1478 static ByteSize data_offset() {
1479 return byte_offset_of(MethodData, _data[0]);
1480 }
1481
1482 static ByteSize invocation_counter_offset() {
1483 return byte_offset_of(MethodData, _invocation_counter);
1484 }
1485 static ByteSize backedge_counter_offset() {
1486 return byte_offset_of(MethodData, _backedge_counter);
1487 }
1488
1489 // Deallocation support - no pointer fields to deallocate
1490 void deallocate_contents(ClassLoaderData* loader_data) {}
1491
1492 // GC support
1493 void set_size(int object_size_in_bytes) { _size = object_size_in_bytes; }
1494
1495 // Printing
1496 #ifndef PRODUCT
1497 void print_on (outputStream* st) const;
1498 #endif
1499 void print_value_on(outputStream* st) const;
1500
1501 #ifndef PRODUCT
1502 // printing support for method data
1503 void print_data_on(outputStream* st) const;
1504 #endif
1505
1506 const char* internal_name() const { return "{method data}"; }
1507
1508 // verification
1509 void verify_on(outputStream* st);
1510 void verify_data_on(outputStream* st);
1511 };
1512
1513 #endif // SHARE_VM_OOPS_METHODDATAOOP_HPP