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
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7 * published by the Free Software Foundation.
8 *
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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).
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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 friend class VMStructs;
76
77 private:
78 // Every data layout begins with a header. This header
79 // contains a tag, which is used to indicate the size/layout
80 // of the data, 4 bits of flags, which can be used in any way,
81 // 4 bits of trap history (none/one reason/many reasons),
82 // and a bci, which is used to tie this piece of data to a
83 // specific bci in the bytecodes.
84 union {
85 intptr_t _bits;
86 struct {
87 u1 _tag;
88 u1 _flags;
89 u2 _bci;
90 } _struct;
91 } _header;
92
93 // The data layout has an arbitrary number of cells, each sized
94 // to accomodate a pointer or an integer.
95 intptr_t _cells[1];
96
97 // Some types of data layouts need a length field.
98 static bool needs_array_len(u1 tag);
99
100 public:
101 enum {
102 counter_increment = 1
103 };
104
105 enum {
106 cell_size = sizeof(intptr_t)
107 };
108
109 // Tag values
110 enum {
111 no_tag,
112 bit_data_tag,
113 counter_data_tag,
114 jump_data_tag,
115 receiver_type_data_tag,
116 virtual_call_data_tag,
117 ret_data_tag,
118 branch_data_tag,
119 multi_branch_data_tag,
120 arg_info_data_tag
121 };
122
123 enum {
124 // The _struct._flags word is formatted as [trap_state:4 | flags:4].
125 // The trap state breaks down further as [recompile:1 | reason:3].
126 // This further breakdown is defined in deoptimization.cpp.
127 // See Deoptimization::trap_state_reason for an assert that
128 // trap_bits is big enough to hold reasons < Reason_RECORDED_LIMIT.
129 //
130 // The trap_state is collected only if ProfileTraps is true.
131 trap_bits = 1+3, // 3: enough to distinguish [0..Reason_RECORDED_LIMIT].
132 trap_shift = BitsPerByte - trap_bits,
133 trap_mask = right_n_bits(trap_bits),
134 trap_mask_in_place = (trap_mask << trap_shift),
135 flag_limit = trap_shift,
136 flag_mask = right_n_bits(flag_limit),
137 first_flag = 0
138 };
139
140 // Size computation
141 static int header_size_in_bytes() {
142 return cell_size;
143 }
144 static int header_size_in_cells() {
145 return 1;
146 }
147
148 static int compute_size_in_bytes(int cell_count) {
149 return header_size_in_bytes() + cell_count * cell_size;
150 }
151
152 // Initialization
153 void initialize(u1 tag, u2 bci, int cell_count);
154
155 // Accessors
156 u1 tag() {
157 return _header._struct._tag;
158 }
159
160 // Return a few bits of trap state. Range is [0..trap_mask].
161 // The state tells if traps with zero, one, or many reasons have occurred.
162 // It also tells whether zero or many recompilations have occurred.
163 // The associated trap histogram in the MDO itself tells whether
164 // traps are common or not. If a BCI shows that a trap X has
165 // occurred, and the MDO shows N occurrences of X, we make the
166 // simplifying assumption that all N occurrences can be blamed
167 // on that BCI.
168 int trap_state() {
169 return ((_header._struct._flags >> trap_shift) & trap_mask);
170 }
171
172 void set_trap_state(int new_state) {
173 assert(ProfileTraps, "used only under +ProfileTraps");
174 uint old_flags = (_header._struct._flags & flag_mask);
175 _header._struct._flags = (new_state << trap_shift) | old_flags;
176 }
177
178 u1 flags() {
179 return _header._struct._flags;
180 }
181
182 u2 bci() {
183 return _header._struct._bci;
184 }
185
186 void set_header(intptr_t value) {
187 _header._bits = value;
188 }
189 void release_set_header(intptr_t value) {
190 OrderAccess::release_store_ptr(&_header._bits, value);
191 }
192 intptr_t header() {
193 return _header._bits;
194 }
195 void set_cell_at(int index, intptr_t value) {
196 _cells[index] = value;
197 }
198 void release_set_cell_at(int index, intptr_t value) {
199 OrderAccess::release_store_ptr(&_cells[index], value);
200 }
201 intptr_t cell_at(int index) {
202 return _cells[index];
203 }
204
205 void set_flag_at(int flag_number) {
206 assert(flag_number < flag_limit, "oob");
207 _header._struct._flags |= (0x1 << flag_number);
208 }
209 bool flag_at(int flag_number) {
210 assert(flag_number < flag_limit, "oob");
211 return (_header._struct._flags & (0x1 << flag_number)) != 0;
212 }
213
214 // Low-level support for code generation.
215 static ByteSize header_offset() {
216 return byte_offset_of(DataLayout, _header);
217 }
218 static ByteSize tag_offset() {
219 return byte_offset_of(DataLayout, _header._struct._tag);
220 }
221 static ByteSize flags_offset() {
222 return byte_offset_of(DataLayout, _header._struct._flags);
223 }
224 static ByteSize bci_offset() {
225 return byte_offset_of(DataLayout, _header._struct._bci);
226 }
227 static ByteSize cell_offset(int index) {
228 return byte_offset_of(DataLayout, _cells) + in_ByteSize(index * cell_size);
229 }
230 // Return a value which, when or-ed as a byte into _flags, sets the flag.
231 static int flag_number_to_byte_constant(int flag_number) {
232 assert(0 <= flag_number && flag_number < flag_limit, "oob");
233 DataLayout temp; temp.set_header(0);
234 temp.set_flag_at(flag_number);
235 return temp._header._struct._flags;
236 }
237 // Return a value which, when or-ed as a word into _header, sets the flag.
238 static intptr_t flag_mask_to_header_mask(int byte_constant) {
239 DataLayout temp; temp.set_header(0);
240 temp._header._struct._flags = byte_constant;
241 return temp._header._bits;
242 }
243
244 ProfileData* data_in();
245
246 // GC support
247 void clean_weak_klass_links(BoolObjectClosure* cl);
248 };
249
250
251 // ProfileData class hierarchy
252 class ProfileData;
253 class BitData;
254 class CounterData;
255 class ReceiverTypeData;
256 class VirtualCallData;
257 class RetData;
258 class JumpData;
259 class BranchData;
260 class ArrayData;
261 class MultiBranchData;
262 class ArgInfoData;
263
264
265 // ProfileData
266 //
267 // A ProfileData object is created to refer to a section of profiling
268 // data in a structured way.
269 class ProfileData : public ResourceObj {
270 private:
271 #ifndef PRODUCT
272 enum {
273 tab_width_one = 16,
274 tab_width_two = 36
275 };
276 #endif // !PRODUCT
277
278 // This is a pointer to a section of profiling data.
279 DataLayout* _data;
280
281 protected:
282 DataLayout* data() { return _data; }
283
284 enum {
285 cell_size = DataLayout::cell_size
286 };
287
288 public:
289 // How many cells are in this?
290 virtual int cell_count() {
291 ShouldNotReachHere();
292 return -1;
293 }
294
295 // Return the size of this data.
296 int size_in_bytes() {
297 return DataLayout::compute_size_in_bytes(cell_count());
298 }
299
300 protected:
301 // Low-level accessors for underlying data
302 void set_intptr_at(int index, intptr_t value) {
303 assert(0 <= index && index < cell_count(), "oob");
304 data()->set_cell_at(index, value);
305 }
306 void release_set_intptr_at(int index, intptr_t value) {
307 assert(0 <= index && index < cell_count(), "oob");
308 data()->release_set_cell_at(index, value);
309 }
310 intptr_t intptr_at(int index) {
311 assert(0 <= index && index < cell_count(), "oob");
312 return data()->cell_at(index);
313 }
314 void set_uint_at(int index, uint value) {
315 set_intptr_at(index, (intptr_t) value);
316 }
317 void release_set_uint_at(int index, uint value) {
318 release_set_intptr_at(index, (intptr_t) value);
319 }
320 uint uint_at(int index) {
321 return (uint)intptr_at(index);
322 }
323 void set_int_at(int index, int value) {
324 set_intptr_at(index, (intptr_t) value);
325 }
326 void release_set_int_at(int index, int value) {
327 release_set_intptr_at(index, (intptr_t) value);
328 }
329 int int_at(int index) {
330 return (int)intptr_at(index);
331 }
332 int int_at_unchecked(int index) {
333 return (int)data()->cell_at(index);
334 }
335 void set_oop_at(int index, oop value) {
336 set_intptr_at(index, (intptr_t) value);
337 }
338 oop oop_at(int index) {
339 return (oop)intptr_at(index);
340 }
341
342 void set_flag_at(int flag_number) {
343 data()->set_flag_at(flag_number);
344 }
345 bool flag_at(int flag_number) {
346 return data()->flag_at(flag_number);
347 }
348
349 // two convenient imports for use by subclasses:
350 static ByteSize cell_offset(int index) {
351 return DataLayout::cell_offset(index);
352 }
353 static int flag_number_to_byte_constant(int flag_number) {
354 return DataLayout::flag_number_to_byte_constant(flag_number);
355 }
356
357 ProfileData(DataLayout* data) {
358 _data = data;
359 }
360
361 public:
362 // Constructor for invalid ProfileData.
363 ProfileData();
364
365 u2 bci() {
366 return data()->bci();
367 }
368
369 address dp() {
370 return (address)_data;
371 }
372
373 int trap_state() {
374 return data()->trap_state();
375 }
376 void set_trap_state(int new_state) {
377 data()->set_trap_state(new_state);
378 }
379
380 // Type checking
381 virtual bool is_BitData() { return false; }
382 virtual bool is_CounterData() { return false; }
383 virtual bool is_JumpData() { return false; }
384 virtual bool is_ReceiverTypeData(){ return false; }
385 virtual bool is_VirtualCallData() { return false; }
386 virtual bool is_RetData() { return false; }
387 virtual bool is_BranchData() { return false; }
388 virtual bool is_ArrayData() { return false; }
389 virtual bool is_MultiBranchData() { return false; }
390 virtual bool is_ArgInfoData() { return false; }
391
392
393 BitData* as_BitData() {
394 assert(is_BitData(), "wrong type");
395 return is_BitData() ? (BitData*) this : NULL;
396 }
397 CounterData* as_CounterData() {
398 assert(is_CounterData(), "wrong type");
399 return is_CounterData() ? (CounterData*) this : NULL;
400 }
401 JumpData* as_JumpData() {
402 assert(is_JumpData(), "wrong type");
403 return is_JumpData() ? (JumpData*) this : NULL;
404 }
405 ReceiverTypeData* as_ReceiverTypeData() {
406 assert(is_ReceiverTypeData(), "wrong type");
407 return is_ReceiverTypeData() ? (ReceiverTypeData*)this : NULL;
408 }
409 VirtualCallData* as_VirtualCallData() {
410 assert(is_VirtualCallData(), "wrong type");
411 return is_VirtualCallData() ? (VirtualCallData*)this : NULL;
412 }
413 RetData* as_RetData() {
414 assert(is_RetData(), "wrong type");
415 return is_RetData() ? (RetData*) this : NULL;
416 }
417 BranchData* as_BranchData() {
418 assert(is_BranchData(), "wrong type");
419 return is_BranchData() ? (BranchData*) this : NULL;
420 }
421 ArrayData* as_ArrayData() {
422 assert(is_ArrayData(), "wrong type");
423 return is_ArrayData() ? (ArrayData*) this : NULL;
424 }
425 MultiBranchData* as_MultiBranchData() {
426 assert(is_MultiBranchData(), "wrong type");
427 return is_MultiBranchData() ? (MultiBranchData*)this : NULL;
428 }
429 ArgInfoData* as_ArgInfoData() {
430 assert(is_ArgInfoData(), "wrong type");
431 return is_ArgInfoData() ? (ArgInfoData*)this : NULL;
432 }
433
434
435 // Subclass specific initialization
436 virtual void post_initialize(BytecodeStream* stream, MethodData* mdo) {}
437
438 // GC support
439 virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure) {}
440
441 // CI translation: ProfileData can represent both MethodDataOop data
442 // as well as CIMethodData data. This function is provided for translating
443 // an oop in a ProfileData to the ci equivalent. Generally speaking,
444 // most ProfileData don't require any translation, so we provide the null
445 // translation here, and the required translators are in the ci subclasses.
446 virtual void translate_from(ProfileData* data) {}
447
448 virtual void print_data_on(outputStream* st) {
449 ShouldNotReachHere();
450 }
451
452 #ifndef PRODUCT
453 void print_shared(outputStream* st, const char* name);
454 void tab(outputStream* st);
455 #endif
456 };
457
458 // BitData
459 //
460 // A BitData holds a flag or two in its header.
461 class BitData : public ProfileData {
462 protected:
463 enum {
464 // null_seen:
465 // saw a null operand (cast/aastore/instanceof)
466 null_seen_flag = DataLayout::first_flag + 0
467 };
468 enum { bit_cell_count = 0 }; // no additional data fields needed.
469 public:
470 BitData(DataLayout* layout) : ProfileData(layout) {
471 }
472
473 virtual bool is_BitData() { return true; }
474
475 static int static_cell_count() {
476 return bit_cell_count;
477 }
478
479 virtual int cell_count() {
480 return static_cell_count();
481 }
482
483 // Accessor
484
485 // The null_seen flag bit is specially known to the interpreter.
486 // Consulting it allows the compiler to avoid setting up null_check traps.
487 bool null_seen() { return flag_at(null_seen_flag); }
488 void set_null_seen() { set_flag_at(null_seen_flag); }
489
490
491 // Code generation support
492 static int null_seen_byte_constant() {
493 return flag_number_to_byte_constant(null_seen_flag);
494 }
495
496 static ByteSize bit_data_size() {
497 return cell_offset(bit_cell_count);
498 }
499
500 #ifndef PRODUCT
501 void print_data_on(outputStream* st);
502 #endif
503 };
504
505 // CounterData
506 //
507 // A CounterData corresponds to a simple counter.
508 class CounterData : public BitData {
509 protected:
510 enum {
511 count_off,
512 counter_cell_count
513 };
514 public:
515 CounterData(DataLayout* layout) : BitData(layout) {}
516
517 virtual bool is_CounterData() { return true; }
518
519 static int static_cell_count() {
520 return counter_cell_count;
521 }
522
523 virtual int cell_count() {
524 return static_cell_count();
525 }
526
527 // Direct accessor
528 uint count() {
529 return uint_at(count_off);
530 }
531
532 // Code generation support
533 static ByteSize count_offset() {
534 return cell_offset(count_off);
535 }
536 static ByteSize counter_data_size() {
537 return cell_offset(counter_cell_count);
538 }
539
540 void set_count(uint count) {
541 set_uint_at(count_off, count);
542 }
543
544 #ifndef PRODUCT
545 void print_data_on(outputStream* st);
546 #endif
547 };
548
549 // JumpData
550 //
551 // A JumpData is used to access profiling information for a direct
552 // branch. It is a counter, used for counting the number of branches,
553 // plus a data displacement, used for realigning the data pointer to
554 // the corresponding target bci.
555 class JumpData : public ProfileData {
556 protected:
557 enum {
558 taken_off_set,
559 displacement_off_set,
560 jump_cell_count
561 };
562
563 void set_displacement(int displacement) {
564 set_int_at(displacement_off_set, displacement);
565 }
566
567 public:
568 JumpData(DataLayout* layout) : ProfileData(layout) {
569 assert(layout->tag() == DataLayout::jump_data_tag ||
570 layout->tag() == DataLayout::branch_data_tag, "wrong type");
571 }
572
573 virtual bool is_JumpData() { return true; }
574
575 static int static_cell_count() {
576 return jump_cell_count;
577 }
578
579 virtual int cell_count() {
580 return static_cell_count();
581 }
582
583 // Direct accessor
584 uint taken() {
585 return uint_at(taken_off_set);
586 }
587
588 void set_taken(uint cnt) {
589 set_uint_at(taken_off_set, cnt);
590 }
591
592 // Saturating counter
593 uint inc_taken() {
594 uint cnt = taken() + 1;
595 // Did we wrap? Will compiler screw us??
596 if (cnt == 0) cnt--;
597 set_uint_at(taken_off_set, cnt);
598 return cnt;
599 }
600
601 int displacement() {
602 return int_at(displacement_off_set);
603 }
604
605 // Code generation support
606 static ByteSize taken_offset() {
607 return cell_offset(taken_off_set);
608 }
609
610 static ByteSize displacement_offset() {
611 return cell_offset(displacement_off_set);
612 }
613
614 // Specific initialization.
615 void post_initialize(BytecodeStream* stream, MethodData* mdo);
616
617 #ifndef PRODUCT
618 void print_data_on(outputStream* st);
619 #endif
620 };
621
622 // ReceiverTypeData
623 //
624 // A ReceiverTypeData is used to access profiling information about a
625 // dynamic type check. It consists of a counter which counts the total times
626 // that the check is reached, and a series of (Klass*, count) pairs
627 // which are used to store a type profile for the receiver of the check.
628 class ReceiverTypeData : public CounterData {
629 protected:
630 enum {
631 receiver0_offset = counter_cell_count,
632 count0_offset,
633 receiver_type_row_cell_count = (count0_offset + 1) - receiver0_offset
634 };
635
636 public:
637 ReceiverTypeData(DataLayout* layout) : CounterData(layout) {
638 assert(layout->tag() == DataLayout::receiver_type_data_tag ||
639 layout->tag() == DataLayout::virtual_call_data_tag, "wrong type");
640 }
641
642 virtual bool is_ReceiverTypeData() { return true; }
643
644 static int static_cell_count() {
645 return counter_cell_count + (uint) TypeProfileWidth * receiver_type_row_cell_count;
646 }
647
648 virtual int cell_count() {
649 return static_cell_count();
650 }
651
652 // Direct accessors
653 static uint row_limit() {
654 return TypeProfileWidth;
655 }
656 static int receiver_cell_index(uint row) {
657 return receiver0_offset + row * receiver_type_row_cell_count;
658 }
659 static int receiver_count_cell_index(uint row) {
660 return count0_offset + row * receiver_type_row_cell_count;
661 }
662
663 Klass* receiver(uint row) {
664 assert(row < row_limit(), "oob");
665
666 Klass* recv = (Klass*)intptr_at(receiver_cell_index(row));
667 assert(recv == NULL || recv->is_klass(), "wrong type");
668 return recv;
669 }
670
671 void set_receiver(uint row, Klass* k) {
672 assert((uint)row < row_limit(), "oob");
673 set_intptr_at(receiver_cell_index(row), (uintptr_t)k);
674 }
675
676 uint receiver_count(uint row) {
677 assert(row < row_limit(), "oob");
678 return uint_at(receiver_count_cell_index(row));
679 }
680
681 void set_receiver_count(uint row, uint count) {
682 assert(row < row_limit(), "oob");
683 set_uint_at(receiver_count_cell_index(row), count);
684 }
685
686 void clear_row(uint row) {
687 assert(row < row_limit(), "oob");
688 // Clear total count - indicator of polymorphic call site.
689 // The site may look like as monomorphic after that but
690 // it allow to have more accurate profiling information because
691 // there was execution phase change since klasses were unloaded.
692 // If the site is still polymorphic then MDO will be updated
693 // to reflect it. But it could be the case that the site becomes
694 // only bimorphic. Then keeping total count not 0 will be wrong.
695 // Even if we use monomorphic (when it is not) for compilation
696 // we will only have trap, deoptimization and recompile again
697 // with updated MDO after executing method in Interpreter.
698 // An additional receiver will be recorded in the cleaned row
699 // during next call execution.
700 //
701 // Note: our profiling logic works with empty rows in any slot.
702 // We do sorting a profiling info (ciCallProfile) for compilation.
703 //
704 set_count(0);
705 set_receiver(row, NULL);
706 set_receiver_count(row, 0);
707 }
708
709 // Code generation support
710 static ByteSize receiver_offset(uint row) {
711 return cell_offset(receiver_cell_index(row));
712 }
713 static ByteSize receiver_count_offset(uint row) {
714 return cell_offset(receiver_count_cell_index(row));
715 }
716 static ByteSize receiver_type_data_size() {
717 return cell_offset(static_cell_count());
718 }
719
720 // GC support
721 virtual void clean_weak_klass_links(BoolObjectClosure* is_alive_closure);
722
723 #ifndef PRODUCT
724 void print_receiver_data_on(outputStream* st);
725 void print_data_on(outputStream* st);
726 #endif
727 };
728
729 // VirtualCallData
730 //
731 // A VirtualCallData is used to access profiling information about a
732 // virtual call. For now, it has nothing more than a ReceiverTypeData.
733 class VirtualCallData : public ReceiverTypeData {
734 public:
735 VirtualCallData(DataLayout* layout) : ReceiverTypeData(layout) {
736 assert(layout->tag() == DataLayout::virtual_call_data_tag, "wrong type");
737 }
738
739 virtual bool is_VirtualCallData() { return true; }
740
741 static int static_cell_count() {
742 // At this point we could add more profile state, e.g., for arguments.
743 // But for now it's the same size as the base record type.
744 return ReceiverTypeData::static_cell_count();
745 }
746
747 virtual int cell_count() {
748 return static_cell_count();
749 }
750
751 // Direct accessors
752 static ByteSize virtual_call_data_size() {
753 return cell_offset(static_cell_count());
754 }
755
756 #ifndef PRODUCT
757 void print_data_on(outputStream* st);
758 #endif
759 };
760
761 // RetData
762 //
763 // A RetData is used to access profiling information for a ret bytecode.
764 // It is composed of a count of the number of times that the ret has
765 // been executed, followed by a series of triples of the form
766 // (bci, count, di) which count the number of times that some bci was the
767 // target of the ret and cache a corresponding data displacement.
768 class RetData : public CounterData {
769 protected:
770 enum {
771 bci0_offset = counter_cell_count,
772 count0_offset,
773 displacement0_offset,
774 ret_row_cell_count = (displacement0_offset + 1) - bci0_offset
775 };
776
777 void set_bci(uint row, int bci) {
778 assert((uint)row < row_limit(), "oob");
779 set_int_at(bci0_offset + row * ret_row_cell_count, bci);
780 }
781 void release_set_bci(uint row, int bci) {
782 assert((uint)row < row_limit(), "oob");
783 // 'release' when setting the bci acts as a valid flag for other
784 // threads wrt bci_count and bci_displacement.
785 release_set_int_at(bci0_offset + row * ret_row_cell_count, bci);
786 }
787 void set_bci_count(uint row, uint count) {
788 assert((uint)row < row_limit(), "oob");
789 set_uint_at(count0_offset + row * ret_row_cell_count, count);
790 }
791 void set_bci_displacement(uint row, int disp) {
792 set_int_at(displacement0_offset + row * ret_row_cell_count, disp);
793 }
794
795 public:
796 RetData(DataLayout* layout) : CounterData(layout) {
797 assert(layout->tag() == DataLayout::ret_data_tag, "wrong type");
798 }
799
800 virtual bool is_RetData() { return true; }
801
802 enum {
803 no_bci = -1 // value of bci when bci1/2 are not in use.
804 };
805
806 static int static_cell_count() {
807 return counter_cell_count + (uint) BciProfileWidth * ret_row_cell_count;
808 }
809
810 virtual int cell_count() {
811 return static_cell_count();
812 }
813
814 static uint row_limit() {
815 return BciProfileWidth;
816 }
817 static int bci_cell_index(uint row) {
818 return bci0_offset + row * ret_row_cell_count;
819 }
820 static int bci_count_cell_index(uint row) {
821 return count0_offset + row * ret_row_cell_count;
822 }
823 static int bci_displacement_cell_index(uint row) {
824 return displacement0_offset + row * ret_row_cell_count;
825 }
826
827 // Direct accessors
828 int bci(uint row) {
829 return int_at(bci_cell_index(row));
830 }
831 uint bci_count(uint row) {
832 return uint_at(bci_count_cell_index(row));
833 }
834 int bci_displacement(uint row) {
835 return int_at(bci_displacement_cell_index(row));
836 }
837
838 // Interpreter Runtime support
839 address fixup_ret(int return_bci, MethodData* mdo);
840
841 // Code generation support
842 static ByteSize bci_offset(uint row) {
843 return cell_offset(bci_cell_index(row));
844 }
845 static ByteSize bci_count_offset(uint row) {
846 return cell_offset(bci_count_cell_index(row));
847 }
848 static ByteSize bci_displacement_offset(uint row) {
849 return cell_offset(bci_displacement_cell_index(row));
850 }
851
852 // Specific initialization.
853 void post_initialize(BytecodeStream* stream, MethodData* mdo);
854
855 #ifndef PRODUCT
856 void print_data_on(outputStream* st);
857 #endif
858 };
859
860 // BranchData
861 //
862 // A BranchData is used to access profiling data for a two-way branch.
863 // It consists of taken and not_taken counts as well as a data displacement
864 // for the taken case.
865 class BranchData : public JumpData {
866 protected:
867 enum {
868 not_taken_off_set = jump_cell_count,
869 branch_cell_count
870 };
871
872 void set_displacement(int displacement) {
873 set_int_at(displacement_off_set, displacement);
874 }
875
876 public:
877 BranchData(DataLayout* layout) : JumpData(layout) {
878 assert(layout->tag() == DataLayout::branch_data_tag, "wrong type");
879 }
880
881 virtual bool is_BranchData() { return true; }
882
883 static int static_cell_count() {
884 return branch_cell_count;
885 }
886
887 virtual int cell_count() {
888 return static_cell_count();
889 }
890
891 // Direct accessor
892 uint not_taken() {
893 return uint_at(not_taken_off_set);
894 }
895
896 void set_not_taken(uint cnt) {
897 set_uint_at(not_taken_off_set, cnt);
898 }
899
900 uint inc_not_taken() {
901 uint cnt = not_taken() + 1;
902 // Did we wrap? Will compiler screw us??
903 if (cnt == 0) cnt--;
904 set_uint_at(not_taken_off_set, cnt);
905 return cnt;
906 }
907
908 // Code generation support
909 static ByteSize not_taken_offset() {
910 return cell_offset(not_taken_off_set);
911 }
912 static ByteSize branch_data_size() {
913 return cell_offset(branch_cell_count);
914 }
915
916 // Specific initialization.
917 void post_initialize(BytecodeStream* stream, MethodData* mdo);
918
919 #ifndef PRODUCT
920 void print_data_on(outputStream* st);
921 #endif
922 };
923
924 // ArrayData
925 //
926 // A ArrayData is a base class for accessing profiling data which does
927 // not have a statically known size. It consists of an array length
928 // and an array start.
929 class ArrayData : public ProfileData {
930 protected:
931 friend class DataLayout;
932
933 enum {
934 array_len_off_set,
935 array_start_off_set
936 };
937
938 uint array_uint_at(int index) {
939 int aindex = index + array_start_off_set;
940 return uint_at(aindex);
941 }
942 int array_int_at(int index) {
943 int aindex = index + array_start_off_set;
944 return int_at(aindex);
945 }
946 oop array_oop_at(int index) {
947 int aindex = index + array_start_off_set;
948 return oop_at(aindex);
949 }
950 void array_set_int_at(int index, int value) {
951 int aindex = index + array_start_off_set;
952 set_int_at(aindex, value);
953 }
954
955 // Code generation support for subclasses.
956 static ByteSize array_element_offset(int index) {
957 return cell_offset(array_start_off_set + index);
958 }
959
960 public:
961 ArrayData(DataLayout* layout) : ProfileData(layout) {}
962
963 virtual bool is_ArrayData() { return true; }
964
965 static int static_cell_count() {
966 return -1;
967 }
968
969 int array_len() {
970 return int_at_unchecked(array_len_off_set);
971 }
972
973 virtual int cell_count() {
974 return array_len() + 1;
975 }
976
977 // Code generation support
978 static ByteSize array_len_offset() {
979 return cell_offset(array_len_off_set);
980 }
981 static ByteSize array_start_offset() {
982 return cell_offset(array_start_off_set);
983 }
984 };
985
986 // MultiBranchData
987 //
988 // A MultiBranchData is used to access profiling information for
989 // a multi-way branch (*switch bytecodes). It consists of a series
990 // of (count, displacement) pairs, which count the number of times each
991 // case was taken and specify the data displacment for each branch target.
992 class MultiBranchData : public ArrayData {
993 protected:
994 enum {
995 default_count_off_set,
996 default_disaplacement_off_set,
997 case_array_start
998 };
999 enum {
1000 relative_count_off_set,
1001 relative_displacement_off_set,
1002 per_case_cell_count
1003 };
1004
1005 void set_default_displacement(int displacement) {
1006 array_set_int_at(default_disaplacement_off_set, displacement);
1007 }
1008 void set_displacement_at(int index, int displacement) {
1009 array_set_int_at(case_array_start +
1010 index * per_case_cell_count +
1011 relative_displacement_off_set,
1012 displacement);
1013 }
1014
1015 public:
1016 MultiBranchData(DataLayout* layout) : ArrayData(layout) {
1017 assert(layout->tag() == DataLayout::multi_branch_data_tag, "wrong type");
1018 }
1019
1020 virtual bool is_MultiBranchData() { return true; }
1021
1022 static int compute_cell_count(BytecodeStream* stream);
1023
1024 int number_of_cases() {
1025 int alen = array_len() - 2; // get rid of default case here.
1026 assert(alen % per_case_cell_count == 0, "must be even");
1027 return (alen / per_case_cell_count);
1028 }
1029
1030 uint default_count() {
1031 return array_uint_at(default_count_off_set);
1032 }
1033 int default_displacement() {
1034 return array_int_at(default_disaplacement_off_set);
1035 }
1036
1037 uint count_at(int index) {
1038 return array_uint_at(case_array_start +
1039 index * per_case_cell_count +
1040 relative_count_off_set);
1041 }
1042 int displacement_at(int index) {
1043 return array_int_at(case_array_start +
1044 index * per_case_cell_count +
1045 relative_displacement_off_set);
1046 }
1047
1048 // Code generation support
1049 static ByteSize default_count_offset() {
1050 return array_element_offset(default_count_off_set);
1051 }
1052 static ByteSize default_displacement_offset() {
1053 return array_element_offset(default_disaplacement_off_set);
1054 }
1055 static ByteSize case_count_offset(int index) {
1056 return case_array_offset() +
1057 (per_case_size() * index) +
1058 relative_count_offset();
1059 }
1060 static ByteSize case_array_offset() {
1061 return array_element_offset(case_array_start);
1062 }
1063 static ByteSize per_case_size() {
1064 return in_ByteSize(per_case_cell_count) * cell_size;
1065 }
1066 static ByteSize relative_count_offset() {
1067 return in_ByteSize(relative_count_off_set) * cell_size;
1068 }
1069 static ByteSize relative_displacement_offset() {
1070 return in_ByteSize(relative_displacement_off_set) * cell_size;
1071 }
1072
1073 // Specific initialization.
1074 void post_initialize(BytecodeStream* stream, MethodData* mdo);
1075
1076 #ifndef PRODUCT
1077 void print_data_on(outputStream* st);
1078 #endif
1079 };
1080
1081 class ArgInfoData : public ArrayData {
1082
1083 public:
1084 ArgInfoData(DataLayout* layout) : ArrayData(layout) {
1085 assert(layout->tag() == DataLayout::arg_info_data_tag, "wrong type");
1086 }
1087
1088 virtual bool is_ArgInfoData() { return true; }
1089
1090
1091 int number_of_args() {
1092 return array_len();
1093 }
1094
1095 uint arg_modified(int arg) {
1096 return array_uint_at(arg);
1097 }
1098
1099 void set_arg_modified(int arg, uint val) {
1100 array_set_int_at(arg, val);
1101 }
1102
1103 #ifndef PRODUCT
1104 void print_data_on(outputStream* st);
1105 #endif
1106 };
1107
1108 // MethodData*
1109 //
1110 // A MethodData* holds information which has been collected about
1111 // a method. Its layout looks like this:
1112 //
1113 // -----------------------------
1114 // | header |
1115 // | klass |
1116 // -----------------------------
1117 // | method |
1118 // | size of the MethodData* |
1119 // -----------------------------
1120 // | Data entries... |
1121 // | (variable size) |
1122 // | |
1123 // . .
1124 // . .
1125 // . .
1126 // | |
1127 // -----------------------------
1128 //
1129 // The data entry area is a heterogeneous array of DataLayouts. Each
1130 // DataLayout in the array corresponds to a specific bytecode in the
1131 // method. The entries in the array are sorted by the corresponding
1132 // bytecode. Access to the data is via resource-allocated ProfileData,
1133 // which point to the underlying blocks of DataLayout structures.
1134 //
1135 // During interpretation, if profiling in enabled, the interpreter
1136 // maintains a method data pointer (mdp), which points at the entry
1137 // in the array corresponding to the current bci. In the course of
1138 // intepretation, when a bytecode is encountered that has profile data
1139 // associated with it, the entry pointed to by mdp is updated, then the
1140 // mdp is adjusted to point to the next appropriate DataLayout. If mdp
1141 // is NULL to begin with, the interpreter assumes that the current method
1142 // is not (yet) being profiled.
1143 //
1144 // In MethodData* parlance, "dp" is a "data pointer", the actual address
1145 // of a DataLayout element. A "di" is a "data index", the offset in bytes
1146 // from the base of the data entry array. A "displacement" is the byte offset
1147 // in certain ProfileData objects that indicate the amount the mdp must be
1148 // adjusted in the event of a change in control flow.
1149 //
1150
1151 class MethodData : public Metadata {
1152 friend class VMStructs;
1153 private:
1154 friend class ProfileData;
1155
1156 // Back pointer to the Method*
1157 Method* _method;
1158
1159 // Size of this oop in bytes
1160 int _size;
1161
1162 // Cached hint for bci_to_dp and bci_to_data
1163 int _hint_di;
1164
1165 MethodData(methodHandle method, int size, TRAPS);
1166 public:
1167 static MethodData* allocate(ClassLoaderData* loader_data, methodHandle method, TRAPS);
1168 MethodData() {}; // For ciMethodData
1169
1170 bool is_methodData() const volatile { return true; }
1171
1172 // Whole-method sticky bits and flags
1173 enum {
1174 _trap_hist_limit = 17, // decoupled from Deoptimization::Reason_LIMIT
1175 _trap_hist_mask = max_jubyte,
1176 _extra_data_count = 4 // extra DataLayout headers, for trap history
1177 }; // Public flag values
1178 private:
1179 uint _nof_decompiles; // count of all nmethod removals
1180 uint _nof_overflow_recompiles; // recompile count, excluding recomp. bits
1181 uint _nof_overflow_traps; // trap count, excluding _trap_hist
1182 union {
1183 intptr_t _align;
1184 u1 _array[_trap_hist_limit];
1185 } _trap_hist;
1186
1187 // Support for interprocedural escape analysis, from Thomas Kotzmann.
1188 intx _eflags; // flags on escape information
1189 intx _arg_local; // bit set of non-escaping arguments
1190 intx _arg_stack; // bit set of stack-allocatable arguments
1191 intx _arg_returned; // bit set of returned arguments
1192
1193 int _creation_mileage; // method mileage at MDO creation
1194
1195 // How many invocations has this MDO seen?
1196 // These counters are used to determine the exact age of MDO.
1197 // We need those because in tiered a method can be concurrently
1198 // executed at different levels.
1199 InvocationCounter _invocation_counter;
1200 // Same for backedges.
1201 InvocationCounter _backedge_counter;
1202 // Counter values at the time profiling started.
1203 int _invocation_counter_start;
1204 int _backedge_counter_start;
1205 // Number of loops and blocks is computed when compiling the first
1206 // time with C1. It is used to determine if method is trivial.
1207 short _num_loops;
1208 short _num_blocks;
1209 // Highest compile level this method has ever seen.
1210 u1 _highest_comp_level;
1211 // Same for OSR level
1212 u1 _highest_osr_comp_level;
1213 // Does this method contain anything worth profiling?
1214 bool _would_profile;
1215
1216 // Size of _data array in bytes. (Excludes header and extra_data fields.)
1217 int _data_size;
1218
1219 // Beginning of the data entries
1220 intptr_t _data[1];
1221
1222 // Helper for size computation
1223 static int compute_data_size(BytecodeStream* stream);
1224 static int bytecode_cell_count(Bytecodes::Code code);
1225 enum { no_profile_data = -1, variable_cell_count = -2 };
1226
1227 // Helper for initialization
1228 DataLayout* data_layout_at(int data_index) const {
1229 assert(data_index % sizeof(intptr_t) == 0, "unaligned");
1230 return (DataLayout*) (((address)_data) + data_index);
1231 }
1232
1233 // Initialize an individual data segment. Returns the size of
1234 // the segment in bytes.
1235 int initialize_data(BytecodeStream* stream, int data_index);
1236
1237 // Helper for data_at
1238 DataLayout* limit_data_position() const {
1239 return (DataLayout*)((address)data_base() + _data_size);
1240 }
1241 bool out_of_bounds(int data_index) const {
1242 return data_index >= data_size();
1243 }
1244
1245 // Give each of the data entries a chance to perform specific
1246 // data initialization.
1247 void post_initialize(BytecodeStream* stream);
1248
1249 // hint accessors
1250 int hint_di() const { return _hint_di; }
1251 void set_hint_di(int di) {
1252 assert(!out_of_bounds(di), "hint_di out of bounds");
1253 _hint_di = di;
1254 }
1255 ProfileData* data_before(int bci) {
1256 // avoid SEGV on this edge case
1257 if (data_size() == 0)
1258 return NULL;
1259 int hint = hint_di();
1260 if (data_layout_at(hint)->bci() <= bci)
1261 return data_at(hint);
1262 return first_data();
1263 }
1264
1265 // What is the index of the first data entry?
1266 int first_di() const { return 0; }
1267
1268 // Find or create an extra ProfileData:
1269 ProfileData* bci_to_extra_data(int bci, bool create_if_missing);
1270
1271 // return the argument info cell
1272 ArgInfoData *arg_info();
1273
1274 public:
1275 static int header_size() {
1276 return sizeof(MethodData)/wordSize;
1277 }
1278
1279 // Compute the size of a MethodData* before it is created.
1280 static int compute_allocation_size_in_bytes(methodHandle method);
1281 static int compute_allocation_size_in_words(methodHandle method);
1282 static int compute_extra_data_count(int data_size, int empty_bc_count);
1283
1284 // Determine if a given bytecode can have profile information.
1285 static bool bytecode_has_profile(Bytecodes::Code code) {
1286 return bytecode_cell_count(code) != no_profile_data;
1287 }
1288
1289 // reset into original state
1290 void init();
1291
1292 // My size
1293 int size_in_bytes() const { return _size; }
1294 int size() const { return align_object_size(align_size_up(_size, BytesPerWord)/BytesPerWord); }
1295 #if INCLUDE_SERVICES
1296 void collect_statistics(KlassSizeStats *sz) const;
1297 #endif
1298
1299 int creation_mileage() const { return _creation_mileage; }
1300 void set_creation_mileage(int x) { _creation_mileage = x; }
1301
1302 int invocation_count() {
1303 if (invocation_counter()->carry()) {
1304 return InvocationCounter::count_limit;
1305 }
1306 return invocation_counter()->count();
1307 }
1308 int backedge_count() {
1309 if (backedge_counter()->carry()) {
1310 return InvocationCounter::count_limit;
1311 }
1312 return backedge_counter()->count();
1313 }
1314
1315 int invocation_count_start() {
1316 if (invocation_counter()->carry()) {
1317 return 0;
1318 }
1319 return _invocation_counter_start;
1320 }
1321
1322 int backedge_count_start() {
1323 if (backedge_counter()->carry()) {
1324 return 0;
1325 }
1326 return _backedge_counter_start;
1327 }
1328
1329 int invocation_count_delta() { return invocation_count() - invocation_count_start(); }
1330 int backedge_count_delta() { return backedge_count() - backedge_count_start(); }
1331
1332 void reset_start_counters() {
1333 _invocation_counter_start = invocation_count();
1334 _backedge_counter_start = backedge_count();
1335 }
1336
1337 InvocationCounter* invocation_counter() { return &_invocation_counter; }
1338 InvocationCounter* backedge_counter() { return &_backedge_counter; }
1339
1340 void set_would_profile(bool p) { _would_profile = p; }
1341 bool would_profile() const { return _would_profile; }
1342
1343 int highest_comp_level() const { return _highest_comp_level; }
1344 void set_highest_comp_level(int level) { _highest_comp_level = level; }
1345 int highest_osr_comp_level() const { return _highest_osr_comp_level; }
1346 void set_highest_osr_comp_level(int level) { _highest_osr_comp_level = level; }
1347
1348 int num_loops() const { return _num_loops; }
1349 void set_num_loops(int n) { _num_loops = n; }
1350 int num_blocks() const { return _num_blocks; }
1351 void set_num_blocks(int n) { _num_blocks = n; }
1352
1353 bool is_mature() const; // consult mileage and ProfileMaturityPercentage
1354 static int mileage_of(Method* m);
1355
1356 // Support for interprocedural escape analysis, from Thomas Kotzmann.
1357 enum EscapeFlag {
1358 estimated = 1 << 0,
1359 return_local = 1 << 1,
1360 return_allocated = 1 << 2,
1361 allocated_escapes = 1 << 3,
1362 unknown_modified = 1 << 4
1363 };
1364
1365 intx eflags() { return _eflags; }
1366 intx arg_local() { return _arg_local; }
1367 intx arg_stack() { return _arg_stack; }
1368 intx arg_returned() { return _arg_returned; }
1369 uint arg_modified(int a) { ArgInfoData *aid = arg_info();
1370 assert(aid != NULL, "arg_info must be not null");
1371 assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
1372 return aid->arg_modified(a); }
1373
1374 void set_eflags(intx v) { _eflags = v; }
1375 void set_arg_local(intx v) { _arg_local = v; }
1376 void set_arg_stack(intx v) { _arg_stack = v; }
1377 void set_arg_returned(intx v) { _arg_returned = v; }
1378 void set_arg_modified(int a, uint v) { ArgInfoData *aid = arg_info();
1379 assert(aid != NULL, "arg_info must be not null");
1380 assert(a >= 0 && a < aid->number_of_args(), "valid argument number");
1381 aid->set_arg_modified(a, v); }
1382
1383 void clear_escape_info() { _eflags = _arg_local = _arg_stack = _arg_returned = 0; }
1384
1385 // Location and size of data area
1386 address data_base() const {
1387 return (address) _data;
1388 }
1389 int data_size() const {
1390 return _data_size;
1391 }
1392
1393 // Accessors
1394 Method* method() const { return _method; }
1395
1396 // Get the data at an arbitrary (sort of) data index.
1397 ProfileData* data_at(int data_index) const;
1398
1399 // Walk through the data in order.
1400 ProfileData* first_data() const { return data_at(first_di()); }
1401 ProfileData* next_data(ProfileData* current) const;
1402 bool is_valid(ProfileData* current) const { return current != NULL; }
1403
1404 // Convert a dp (data pointer) to a di (data index).
1405 int dp_to_di(address dp) const {
1406 return dp - ((address)_data);
1407 }
1408
1409 address di_to_dp(int di) {
1410 return (address)data_layout_at(di);
1411 }
1412
1413 // bci to di/dp conversion.
1414 address bci_to_dp(int bci);
1415 int bci_to_di(int bci) {
1416 return dp_to_di(bci_to_dp(bci));
1417 }
1418
1419 // Get the data at an arbitrary bci, or NULL if there is none.
1420 ProfileData* bci_to_data(int bci);
1421
1422 // Same, but try to create an extra_data record if one is needed:
1423 ProfileData* allocate_bci_to_data(int bci) {
1424 ProfileData* data = bci_to_data(bci);
1425 return (data != NULL) ? data : bci_to_extra_data(bci, true);
1426 }
1427
1428 // Add a handful of extra data records, for trap tracking.
1429 DataLayout* extra_data_base() const { return limit_data_position(); }
1430 DataLayout* extra_data_limit() const { return (DataLayout*)((address)this + size_in_bytes()); }
1431 int extra_data_size() const { return (address)extra_data_limit()
1432 - (address)extra_data_base(); }
1433 static DataLayout* next_extra(DataLayout* dp) { return (DataLayout*)((address)dp + in_bytes(DataLayout::cell_offset(0))); }
1434
1435 // Return (uint)-1 for overflow.
1436 uint trap_count(int reason) const {
1437 assert((uint)reason < _trap_hist_limit, "oob");
1438 return (int)((_trap_hist._array[reason]+1) & _trap_hist_mask) - 1;
1439 }
1440 // For loops:
1441 static uint trap_reason_limit() { return _trap_hist_limit; }
1442 static uint trap_count_limit() { return _trap_hist_mask; }
1443 uint inc_trap_count(int reason) {
1444 // Count another trap, anywhere in this method.
1445 assert(reason >= 0, "must be single trap");
1446 if ((uint)reason < _trap_hist_limit) {
1447 uint cnt1 = 1 + _trap_hist._array[reason];
1448 if ((cnt1 & _trap_hist_mask) != 0) { // if no counter overflow...
1449 _trap_hist._array[reason] = cnt1;
1450 return cnt1;
1451 } else {
1452 return _trap_hist_mask + (++_nof_overflow_traps);
1453 }
1454 } else {
1455 // Could not represent the count in the histogram.
1456 return (++_nof_overflow_traps);
1457 }
1458 }
1459
1460 uint overflow_trap_count() const {
1461 return _nof_overflow_traps;
1462 }
1463 uint overflow_recompile_count() const {
1464 return _nof_overflow_recompiles;
1465 }
1466 void inc_overflow_recompile_count() {
1467 _nof_overflow_recompiles += 1;
1468 }
1469 uint decompile_count() const {
1470 return _nof_decompiles;
1471 }
1472 void inc_decompile_count() {
1473 _nof_decompiles += 1;
1474 if (decompile_count() > (uint)PerMethodRecompilationCutoff) {
1475 method()->set_not_compilable(CompLevel_full_optimization, true, "decompile_count > PerMethodRecompilationCutoff");
1476 }
1477 }
1478
1479 // Support for code generation
1480 static ByteSize data_offset() {
1481 return byte_offset_of(MethodData, _data[0]);
1482 }
1483
1484 static ByteSize invocation_counter_offset() {
1485 return byte_offset_of(MethodData, _invocation_counter);
1486 }
1487 static ByteSize backedge_counter_offset() {
1488 return byte_offset_of(MethodData, _backedge_counter);
1489 }
1490
1491 // Deallocation support - no pointer fields to deallocate
1492 void deallocate_contents(ClassLoaderData* loader_data) {}
1493
1494 // GC support
1495 void set_size(int object_size_in_bytes) { _size = object_size_in_bytes; }
1496
1497 // Printing
1498 #ifndef PRODUCT
1499 void print_on (outputStream* st) const;
1500 #endif
1501 void print_value_on(outputStream* st) const;
1502
1503 #ifndef PRODUCT
1504 // printing support for method data
1505 void print_data_on(outputStream* st) const;
1506 #endif
1507
1508 const char* internal_name() const { return "{method data}"; }
1509
1510 // verification
1511 void verify_on(outputStream* st);
1512 void verify_data_on(outputStream* st);
1513 };
1514
1515 #endif // SHARE_VM_OOPS_METHODDATAOOP_HPP