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 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "classfile/systemDictionary.hpp"
27 #include "interpreter/bytecode.hpp"
28 #include "interpreter/bytecodeStream.hpp"
29 #include "interpreter/linkResolver.hpp"
30 #include "memory/heapInspection.hpp"
31 #include "oops/methodData.hpp"
32 #include "prims/jvmtiRedefineClasses.hpp"
33 #include "runtime/compilationPolicy.hpp"
34 #include "runtime/deoptimization.hpp"
35 #include "runtime/handles.inline.hpp"
36
37 // ==================================================================
38 // DataLayout
39 //
40 // Overlay for generic profiling data.
41
42 // Some types of data layouts need a length field.
43 bool DataLayout::needs_array_len(u1 tag) {
44 return (tag == multi_branch_data_tag) || (tag == arg_info_data_tag);
45 }
46
47 // Perform generic initialization of the data. More specific
48 // initialization occurs in overrides of ProfileData::post_initialize.
49 void DataLayout::initialize(u1 tag, u2 bci, int cell_count) {
50 _header._bits = (intptr_t)0;
51 _header._struct._tag = tag;
52 _header._struct._bci = bci;
53 for (int i = 0; i < cell_count; i++) {
54 set_cell_at(i, (intptr_t)0);
55 }
56 if (needs_array_len(tag)) {
57 set_cell_at(ArrayData::array_len_off_set, cell_count - 1); // -1 for header.
58 }
59 }
60
61 void DataLayout::clean_weak_klass_links(BoolObjectClosure* cl) {
62 ResourceMark m;
63 data_in()->clean_weak_klass_links(cl);
64 }
65
66
67 // ==================================================================
68 // ProfileData
69 //
70 // A ProfileData object is created to refer to a section of profiling
71 // data in a structured way.
72
73 // Constructor for invalid ProfileData.
74 ProfileData::ProfileData() {
75 _data = NULL;
76 }
77
78 #ifndef PRODUCT
79 void ProfileData::print_shared(outputStream* st, const char* name) {
80 st->print("bci: %d", bci());
81 st->fill_to(tab_width_one);
82 st->print("%s", name);
83 tab(st);
84 int trap = trap_state();
85 if (trap != 0) {
86 char buf[100];
87 st->print("trap(%s) ", Deoptimization::format_trap_state(buf, sizeof(buf), trap));
88 }
89 int flags = data()->flags();
90 if (flags != 0)
91 st->print("flags(%d) ", flags);
92 }
93
94 void ProfileData::tab(outputStream* st) {
95 st->fill_to(tab_width_two);
96 }
97 #endif // !PRODUCT
98
99 // ==================================================================
100 // BitData
101 //
102 // A BitData corresponds to a one-bit flag. This is used to indicate
103 // whether a checkcast bytecode has seen a null value.
104
105
106 #ifndef PRODUCT
107 void BitData::print_data_on(outputStream* st) {
108 print_shared(st, "BitData");
109 }
110 #endif // !PRODUCT
111
112 // ==================================================================
113 // CounterData
114 //
115 // A CounterData corresponds to a simple counter.
116
117 #ifndef PRODUCT
118 void CounterData::print_data_on(outputStream* st) {
119 print_shared(st, "CounterData");
120 st->print_cr("count(%u)", count());
121 }
122 #endif // !PRODUCT
123
124 // ==================================================================
125 // JumpData
126 //
127 // A JumpData is used to access profiling information for a direct
128 // branch. It is a counter, used for counting the number of branches,
129 // plus a data displacement, used for realigning the data pointer to
130 // the corresponding target bci.
131
132 void JumpData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
133 assert(stream->bci() == bci(), "wrong pos");
134 int target;
135 Bytecodes::Code c = stream->code();
136 if (c == Bytecodes::_goto_w || c == Bytecodes::_jsr_w) {
137 target = stream->dest_w();
138 } else {
139 target = stream->dest();
140 }
141 int my_di = mdo->dp_to_di(dp());
142 int target_di = mdo->bci_to_di(target);
143 int offset = target_di - my_di;
144 set_displacement(offset);
145 }
146
147 #ifndef PRODUCT
148 void JumpData::print_data_on(outputStream* st) {
149 print_shared(st, "JumpData");
150 st->print_cr("taken(%u) displacement(%d)", taken(), displacement());
151 }
152 #endif // !PRODUCT
153
154 // ==================================================================
155 // ReceiverTypeData
156 //
157 // A ReceiverTypeData is used to access profiling information about a
158 // dynamic type check. It consists of a counter which counts the total times
159 // that the check is reached, and a series of (Klass*, count) pairs
160 // which are used to store a type profile for the receiver of the check.
161
162 void ReceiverTypeData::clean_weak_klass_links(BoolObjectClosure* is_alive_cl) {
163 for (uint row = 0; row < row_limit(); row++) {
164 Klass* p = receiver(row);
165 if (p != NULL && !p->is_loader_alive(is_alive_cl)) {
166 clear_row(row);
167 }
168 }
169 }
170
171 #ifndef PRODUCT
172 void ReceiverTypeData::print_receiver_data_on(outputStream* st) {
173 uint row;
174 int entries = 0;
175 for (row = 0; row < row_limit(); row++) {
176 if (receiver(row) != NULL) entries++;
177 }
178 st->print_cr("count(%u) entries(%u)", count(), entries);
179 int total = count();
180 for (row = 0; row < row_limit(); row++) {
181 if (receiver(row) != NULL) {
182 total += receiver_count(row);
183 }
184 }
185 for (row = 0; row < row_limit(); row++) {
186 if (receiver(row) != NULL) {
187 tab(st);
188 receiver(row)->print_value_on(st);
189 st->print_cr("(%u %4.2f)", receiver_count(row), (float) receiver_count(row) / (float) total);
190 }
191 }
192 }
193 void ReceiverTypeData::print_data_on(outputStream* st) {
194 print_shared(st, "ReceiverTypeData");
195 print_receiver_data_on(st);
196 }
197 void VirtualCallData::print_data_on(outputStream* st) {
198 print_shared(st, "VirtualCallData");
199 print_receiver_data_on(st);
200 }
201 #endif // !PRODUCT
202
203 // ==================================================================
204 // RetData
205 //
206 // A RetData is used to access profiling information for a ret bytecode.
207 // It is composed of a count of the number of times that the ret has
208 // been executed, followed by a series of triples of the form
209 // (bci, count, di) which count the number of times that some bci was the
210 // target of the ret and cache a corresponding displacement.
211
212 void RetData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
213 for (uint row = 0; row < row_limit(); row++) {
214 set_bci_displacement(row, -1);
215 set_bci(row, no_bci);
216 }
217 // release so other threads see a consistent state. bci is used as
218 // a valid flag for bci_displacement.
219 OrderAccess::release();
220 }
221
222 // This routine needs to atomically update the RetData structure, so the
223 // caller needs to hold the RetData_lock before it gets here. Since taking
224 // the lock can block (and allow GC) and since RetData is a ProfileData is a
225 // wrapper around a derived oop, taking the lock in _this_ method will
226 // basically cause the 'this' pointer's _data field to contain junk after the
227 // lock. We require the caller to take the lock before making the ProfileData
228 // structure. Currently the only caller is InterpreterRuntime::update_mdp_for_ret
229 address RetData::fixup_ret(int return_bci, MethodData* h_mdo) {
230 // First find the mdp which corresponds to the return bci.
231 address mdp = h_mdo->bci_to_dp(return_bci);
232
233 // Now check to see if any of the cache slots are open.
234 for (uint row = 0; row < row_limit(); row++) {
235 if (bci(row) == no_bci) {
236 set_bci_displacement(row, mdp - dp());
237 set_bci_count(row, DataLayout::counter_increment);
238 // Barrier to ensure displacement is written before the bci; allows
239 // the interpreter to read displacement without fear of race condition.
240 release_set_bci(row, return_bci);
241 break;
242 }
243 }
244 return mdp;
245 }
246
247
248 #ifndef PRODUCT
249 void RetData::print_data_on(outputStream* st) {
250 print_shared(st, "RetData");
251 uint row;
252 int entries = 0;
253 for (row = 0; row < row_limit(); row++) {
254 if (bci(row) != no_bci) entries++;
255 }
256 st->print_cr("count(%u) entries(%u)", count(), entries);
257 for (row = 0; row < row_limit(); row++) {
258 if (bci(row) != no_bci) {
259 tab(st);
260 st->print_cr("bci(%d: count(%u) displacement(%d))",
261 bci(row), bci_count(row), bci_displacement(row));
262 }
263 }
264 }
265 #endif // !PRODUCT
266
267 // ==================================================================
268 // BranchData
269 //
270 // A BranchData is used to access profiling data for a two-way branch.
271 // It consists of taken and not_taken counts as well as a data displacement
272 // for the taken case.
273
274 void BranchData::post_initialize(BytecodeStream* stream, MethodData* mdo) {
275 assert(stream->bci() == bci(), "wrong pos");
276 int target = stream->dest();
277 int my_di = mdo->dp_to_di(dp());
278 int target_di = mdo->bci_to_di(target);
279 int offset = target_di - my_di;
280 set_displacement(offset);
281 }
282
283 #ifndef PRODUCT
284 void BranchData::print_data_on(outputStream* st) {
285 print_shared(st, "BranchData");
286 st->print_cr("taken(%u) displacement(%d)",
287 taken(), displacement());
288 tab(st);
289 st->print_cr("not taken(%u)", not_taken());
290 }
291 #endif
292
293 // ==================================================================
294 // MultiBranchData
295 //
296 // A MultiBranchData is used to access profiling information for
297 // a multi-way branch (*switch bytecodes). It consists of a series
298 // of (count, displacement) pairs, which count the number of times each
299 // case was taken and specify the data displacment for each branch target.
300
301 int MultiBranchData::compute_cell_count(BytecodeStream* stream) {
302 int cell_count = 0;
303 if (stream->code() == Bytecodes::_tableswitch) {
304 Bytecode_tableswitch sw(stream->method()(), stream->bcp());
305 cell_count = 1 + per_case_cell_count * (1 + sw.length()); // 1 for default
306 } else {
307 Bytecode_lookupswitch sw(stream->method()(), stream->bcp());
308 cell_count = 1 + per_case_cell_count * (sw.number_of_pairs() + 1); // 1 for default
309 }
310 return cell_count;
311 }
312
313 void MultiBranchData::post_initialize(BytecodeStream* stream,
314 MethodData* mdo) {
315 assert(stream->bci() == bci(), "wrong pos");
316 int target;
317 int my_di;
318 int target_di;
319 int offset;
320 if (stream->code() == Bytecodes::_tableswitch) {
321 Bytecode_tableswitch sw(stream->method()(), stream->bcp());
322 int len = sw.length();
323 assert(array_len() == per_case_cell_count * (len + 1), "wrong len");
324 for (int count = 0; count < len; count++) {
325 target = sw.dest_offset_at(count) + bci();
326 my_di = mdo->dp_to_di(dp());
327 target_di = mdo->bci_to_di(target);
328 offset = target_di - my_di;
329 set_displacement_at(count, offset);
330 }
331 target = sw.default_offset() + bci();
332 my_di = mdo->dp_to_di(dp());
333 target_di = mdo->bci_to_di(target);
334 offset = target_di - my_di;
335 set_default_displacement(offset);
336
337 } else {
338 Bytecode_lookupswitch sw(stream->method()(), stream->bcp());
339 int npairs = sw.number_of_pairs();
340 assert(array_len() == per_case_cell_count * (npairs + 1), "wrong len");
341 for (int count = 0; count < npairs; count++) {
342 LookupswitchPair pair = sw.pair_at(count);
343 target = pair.offset() + bci();
344 my_di = mdo->dp_to_di(dp());
345 target_di = mdo->bci_to_di(target);
346 offset = target_di - my_di;
347 set_displacement_at(count, offset);
348 }
349 target = sw.default_offset() + bci();
350 my_di = mdo->dp_to_di(dp());
351 target_di = mdo->bci_to_di(target);
352 offset = target_di - my_di;
353 set_default_displacement(offset);
354 }
355 }
356
357 #ifndef PRODUCT
358 void MultiBranchData::print_data_on(outputStream* st) {
359 print_shared(st, "MultiBranchData");
360 st->print_cr("default_count(%u) displacement(%d)",
361 default_count(), default_displacement());
362 int cases = number_of_cases();
363 for (int i = 0; i < cases; i++) {
364 tab(st);
365 st->print_cr("count(%u) displacement(%d)",
366 count_at(i), displacement_at(i));
367 }
368 }
369 #endif
370
371 #ifndef PRODUCT
372 void ArgInfoData::print_data_on(outputStream* st) {
373 print_shared(st, "ArgInfoData");
374 int nargs = number_of_args();
375 for (int i = 0; i < nargs; i++) {
376 st->print(" 0x%x", arg_modified(i));
377 }
378 st->cr();
379 }
380
381 #endif
382 // ==================================================================
383 // MethodData*
384 //
385 // A MethodData* holds information which has been collected about
386 // a method.
387
388 MethodData* MethodData::allocate(ClassLoaderData* loader_data, methodHandle method, TRAPS) {
389 int size = MethodData::compute_allocation_size_in_words(method);
390
391 return new (loader_data, size, false, THREAD) MethodData(method(), size, CHECK_NULL);
392 }
393
394 int MethodData::bytecode_cell_count(Bytecodes::Code code) {
395 switch (code) {
396 case Bytecodes::_checkcast:
397 case Bytecodes::_instanceof:
398 case Bytecodes::_aastore:
399 if (TypeProfileCasts) {
400 return ReceiverTypeData::static_cell_count();
401 } else {
402 return BitData::static_cell_count();
403 }
404 case Bytecodes::_invokespecial:
405 case Bytecodes::_invokestatic:
406 return CounterData::static_cell_count();
407 case Bytecodes::_goto:
408 case Bytecodes::_goto_w:
409 case Bytecodes::_jsr:
410 case Bytecodes::_jsr_w:
411 return JumpData::static_cell_count();
412 case Bytecodes::_invokevirtual:
413 case Bytecodes::_invokeinterface:
414 return VirtualCallData::static_cell_count();
415 case Bytecodes::_invokedynamic:
416 return CounterData::static_cell_count();
417 case Bytecodes::_ret:
418 return RetData::static_cell_count();
419 case Bytecodes::_ifeq:
420 case Bytecodes::_ifne:
421 case Bytecodes::_iflt:
422 case Bytecodes::_ifge:
423 case Bytecodes::_ifgt:
424 case Bytecodes::_ifle:
425 case Bytecodes::_if_icmpeq:
426 case Bytecodes::_if_icmpne:
427 case Bytecodes::_if_icmplt:
428 case Bytecodes::_if_icmpge:
429 case Bytecodes::_if_icmpgt:
430 case Bytecodes::_if_icmple:
431 case Bytecodes::_if_acmpeq:
432 case Bytecodes::_if_acmpne:
433 case Bytecodes::_ifnull:
434 case Bytecodes::_ifnonnull:
435 return BranchData::static_cell_count();
436 case Bytecodes::_lookupswitch:
437 case Bytecodes::_tableswitch:
438 return variable_cell_count;
439 }
440 return no_profile_data;
441 }
442
443 // Compute the size of the profiling information corresponding to
444 // the current bytecode.
445 int MethodData::compute_data_size(BytecodeStream* stream) {
446 int cell_count = bytecode_cell_count(stream->code());
447 if (cell_count == no_profile_data) {
448 return 0;
449 }
450 if (cell_count == variable_cell_count) {
451 cell_count = MultiBranchData::compute_cell_count(stream);
452 }
453 // Note: cell_count might be zero, meaning that there is just
454 // a DataLayout header, with no extra cells.
455 assert(cell_count >= 0, "sanity");
456 return DataLayout::compute_size_in_bytes(cell_count);
457 }
458
459 int MethodData::compute_extra_data_count(int data_size, int empty_bc_count) {
460 if (ProfileTraps) {
461 // Assume that up to 3% of BCIs with no MDP will need to allocate one.
462 int extra_data_count = (uint)(empty_bc_count * 3) / 128 + 1;
463 // If the method is large, let the extra BCIs grow numerous (to ~1%).
464 int one_percent_of_data
465 = (uint)data_size / (DataLayout::header_size_in_bytes()*128);
466 if (extra_data_count < one_percent_of_data)
467 extra_data_count = one_percent_of_data;
468 if (extra_data_count > empty_bc_count)
469 extra_data_count = empty_bc_count; // no need for more
470 return extra_data_count;
471 } else {
472 return 0;
473 }
474 }
475
476 // Compute the size of the MethodData* necessary to store
477 // profiling information about a given method. Size is in bytes.
478 int MethodData::compute_allocation_size_in_bytes(methodHandle method) {
479 int data_size = 0;
480 BytecodeStream stream(method);
481 Bytecodes::Code c;
482 int empty_bc_count = 0; // number of bytecodes lacking data
483 while ((c = stream.next()) >= 0) {
484 int size_in_bytes = compute_data_size(&stream);
485 data_size += size_in_bytes;
486 if (size_in_bytes == 0) empty_bc_count += 1;
487 }
488 int object_size = in_bytes(data_offset()) + data_size;
489
490 // Add some extra DataLayout cells (at least one) to track stray traps.
491 int extra_data_count = compute_extra_data_count(data_size, empty_bc_count);
492 object_size += extra_data_count * DataLayout::compute_size_in_bytes(0);
493
494 // Add a cell to record information about modified arguments.
495 int arg_size = method->size_of_parameters();
496 object_size += DataLayout::compute_size_in_bytes(arg_size+1);
497 return object_size;
498 }
499
500 // Compute the size of the MethodData* necessary to store
501 // profiling information about a given method. Size is in words
502 int MethodData::compute_allocation_size_in_words(methodHandle method) {
503 int byte_size = compute_allocation_size_in_bytes(method);
504 int word_size = align_size_up(byte_size, BytesPerWord) / BytesPerWord;
505 return align_object_size(word_size);
506 }
507
508 // Initialize an individual data segment. Returns the size of
509 // the segment in bytes.
510 int MethodData::initialize_data(BytecodeStream* stream,
511 int data_index) {
512 int cell_count = -1;
513 int tag = DataLayout::no_tag;
514 DataLayout* data_layout = data_layout_at(data_index);
515 Bytecodes::Code c = stream->code();
516 switch (c) {
517 case Bytecodes::_checkcast:
518 case Bytecodes::_instanceof:
519 case Bytecodes::_aastore:
520 if (TypeProfileCasts) {
521 cell_count = ReceiverTypeData::static_cell_count();
522 tag = DataLayout::receiver_type_data_tag;
523 } else {
524 cell_count = BitData::static_cell_count();
525 tag = DataLayout::bit_data_tag;
526 }
527 break;
528 case Bytecodes::_invokespecial:
529 case Bytecodes::_invokestatic:
530 cell_count = CounterData::static_cell_count();
531 tag = DataLayout::counter_data_tag;
532 break;
533 case Bytecodes::_goto:
534 case Bytecodes::_goto_w:
535 case Bytecodes::_jsr:
536 case Bytecodes::_jsr_w:
537 cell_count = JumpData::static_cell_count();
538 tag = DataLayout::jump_data_tag;
539 break;
540 case Bytecodes::_invokevirtual:
541 case Bytecodes::_invokeinterface:
542 cell_count = VirtualCallData::static_cell_count();
543 tag = DataLayout::virtual_call_data_tag;
544 break;
545 case Bytecodes::_invokedynamic:
546 // %%% should make a type profile for any invokedynamic that takes a ref argument
547 cell_count = CounterData::static_cell_count();
548 tag = DataLayout::counter_data_tag;
549 break;
550 case Bytecodes::_ret:
551 cell_count = RetData::static_cell_count();
552 tag = DataLayout::ret_data_tag;
553 break;
554 case Bytecodes::_ifeq:
555 case Bytecodes::_ifne:
556 case Bytecodes::_iflt:
557 case Bytecodes::_ifge:
558 case Bytecodes::_ifgt:
559 case Bytecodes::_ifle:
560 case Bytecodes::_if_icmpeq:
561 case Bytecodes::_if_icmpne:
562 case Bytecodes::_if_icmplt:
563 case Bytecodes::_if_icmpge:
564 case Bytecodes::_if_icmpgt:
565 case Bytecodes::_if_icmple:
566 case Bytecodes::_if_acmpeq:
567 case Bytecodes::_if_acmpne:
568 case Bytecodes::_ifnull:
569 case Bytecodes::_ifnonnull:
570 cell_count = BranchData::static_cell_count();
571 tag = DataLayout::branch_data_tag;
572 break;
573 case Bytecodes::_lookupswitch:
574 case Bytecodes::_tableswitch:
575 cell_count = MultiBranchData::compute_cell_count(stream);
576 tag = DataLayout::multi_branch_data_tag;
577 break;
578 }
579 assert(tag == DataLayout::multi_branch_data_tag ||
580 cell_count == bytecode_cell_count(c), "cell counts must agree");
581 if (cell_count >= 0) {
582 assert(tag != DataLayout::no_tag, "bad tag");
583 assert(bytecode_has_profile(c), "agree w/ BHP");
584 data_layout->initialize(tag, stream->bci(), cell_count);
585 return DataLayout::compute_size_in_bytes(cell_count);
586 } else {
587 assert(!bytecode_has_profile(c), "agree w/ !BHP");
588 return 0;
589 }
590 }
591
592 // Get the data at an arbitrary (sort of) data index.
593 ProfileData* MethodData::data_at(int data_index) const {
594 if (out_of_bounds(data_index)) {
595 return NULL;
596 }
597 DataLayout* data_layout = data_layout_at(data_index);
598 return data_layout->data_in();
599 }
600
601 ProfileData* DataLayout::data_in() {
602 switch (tag()) {
603 case DataLayout::no_tag:
604 default:
605 ShouldNotReachHere();
606 return NULL;
607 case DataLayout::bit_data_tag:
608 return new BitData(this);
609 case DataLayout::counter_data_tag:
610 return new CounterData(this);
611 case DataLayout::jump_data_tag:
612 return new JumpData(this);
613 case DataLayout::receiver_type_data_tag:
614 return new ReceiverTypeData(this);
615 case DataLayout::virtual_call_data_tag:
616 return new VirtualCallData(this);
617 case DataLayout::ret_data_tag:
618 return new RetData(this);
619 case DataLayout::branch_data_tag:
620 return new BranchData(this);
621 case DataLayout::multi_branch_data_tag:
622 return new MultiBranchData(this);
623 case DataLayout::arg_info_data_tag:
624 return new ArgInfoData(this);
625 };
626 }
627
628 // Iteration over data.
629 ProfileData* MethodData::next_data(ProfileData* current) const {
630 int current_index = dp_to_di(current->dp());
631 int next_index = current_index + current->size_in_bytes();
632 ProfileData* next = data_at(next_index);
633 return next;
634 }
635
636 // Give each of the data entries a chance to perform specific
637 // data initialization.
638 void MethodData::post_initialize(BytecodeStream* stream) {
639 ResourceMark rm;
640 ProfileData* data;
641 for (data = first_data(); is_valid(data); data = next_data(data)) {
642 stream->set_start(data->bci());
643 stream->next();
644 data->post_initialize(stream, this);
645 }
646 }
647
648 // Initialize the MethodData* corresponding to a given method.
649 MethodData::MethodData(methodHandle method, int size, TRAPS) {
650 No_Safepoint_Verifier no_safepoint; // init function atomic wrt GC
651 ResourceMark rm;
652 // Set the method back-pointer.
653 _method = method();
654
655 init();
656 set_creation_mileage(mileage_of(method()));
657
658 // Go through the bytecodes and allocate and initialize the
659 // corresponding data cells.
660 int data_size = 0;
661 int empty_bc_count = 0; // number of bytecodes lacking data
662 _data[0] = 0; // apparently not set below.
663 BytecodeStream stream(method);
664 Bytecodes::Code c;
665 while ((c = stream.next()) >= 0) {
666 int size_in_bytes = initialize_data(&stream, data_size);
667 data_size += size_in_bytes;
668 if (size_in_bytes == 0) empty_bc_count += 1;
669 }
670 _data_size = data_size;
671 int object_size = in_bytes(data_offset()) + data_size;
672
673 // Add some extra DataLayout cells (at least one) to track stray traps.
674 int extra_data_count = compute_extra_data_count(data_size, empty_bc_count);
675 int extra_size = extra_data_count * DataLayout::compute_size_in_bytes(0);
676
677 // Add a cell to record information about modified arguments.
678 // Set up _args_modified array after traps cells so that
679 // the code for traps cells works.
680 DataLayout *dp = data_layout_at(data_size + extra_size);
681
682 int arg_size = method->size_of_parameters();
683 dp->initialize(DataLayout::arg_info_data_tag, 0, arg_size+1);
684
685 object_size += extra_size + DataLayout::compute_size_in_bytes(arg_size+1);
686
687 // Set an initial hint. Don't use set_hint_di() because
688 // first_di() may be out of bounds if data_size is 0.
689 // In that situation, _hint_di is never used, but at
690 // least well-defined.
691 _hint_di = first_di();
692
693 post_initialize(&stream);
694
695 set_size(object_size);
696 }
697
698 void MethodData::init() {
699 _invocation_counter.init();
700 _backedge_counter.init();
701 _invocation_counter_start = 0;
702 _backedge_counter_start = 0;
703 _num_loops = 0;
704 _num_blocks = 0;
705 _highest_comp_level = 0;
706 _highest_osr_comp_level = 0;
707 _would_profile = true;
708
709 // Initialize flags and trap history.
710 _nof_decompiles = 0;
711 _nof_overflow_recompiles = 0;
712 _nof_overflow_traps = 0;
713 clear_escape_info();
714 assert(sizeof(_trap_hist) % sizeof(HeapWord) == 0, "align");
715 Copy::zero_to_words((HeapWord*) &_trap_hist,
716 sizeof(_trap_hist) / sizeof(HeapWord));
717 }
718
719 // Get a measure of how much mileage the method has on it.
720 int MethodData::mileage_of(Method* method) {
721 int mileage = 0;
722 if (TieredCompilation) {
723 mileage = MAX2(method->invocation_count(), method->backedge_count());
724 } else {
725 int iic = method->interpreter_invocation_count();
726 if (mileage < iic) mileage = iic;
727 InvocationCounter* ic = method->invocation_counter();
728 InvocationCounter* bc = method->backedge_counter();
729 int icval = ic->count();
730 if (ic->carry()) icval += CompileThreshold;
731 if (mileage < icval) mileage = icval;
732 int bcval = bc->count();
733 if (bc->carry()) bcval += CompileThreshold;
734 if (mileage < bcval) mileage = bcval;
735 }
736 return mileage;
737 }
738
739 bool MethodData::is_mature() const {
740 return CompilationPolicy::policy()->is_mature(_method);
741 }
742
743 // Translate a bci to its corresponding data index (di).
744 address MethodData::bci_to_dp(int bci) {
745 ResourceMark rm;
746 ProfileData* data = data_before(bci);
747 ProfileData* prev = NULL;
748 for ( ; is_valid(data); data = next_data(data)) {
749 if (data->bci() >= bci) {
750 if (data->bci() == bci) set_hint_di(dp_to_di(data->dp()));
751 else if (prev != NULL) set_hint_di(dp_to_di(prev->dp()));
752 return data->dp();
753 }
754 prev = data;
755 }
756 return (address)limit_data_position();
757 }
758
759 // Translate a bci to its corresponding data, or NULL.
760 ProfileData* MethodData::bci_to_data(int bci) {
761 ProfileData* data = data_before(bci);
762 for ( ; is_valid(data); data = next_data(data)) {
763 if (data->bci() == bci) {
764 set_hint_di(dp_to_di(data->dp()));
765 return data;
766 } else if (data->bci() > bci) {
767 break;
768 }
769 }
770 return bci_to_extra_data(bci, false);
771 }
772
773 // Translate a bci to its corresponding extra data, or NULL.
774 ProfileData* MethodData::bci_to_extra_data(int bci, bool create_if_missing) {
775 DataLayout* dp = extra_data_base();
776 DataLayout* end = extra_data_limit();
777 DataLayout* avail = NULL;
778 for (; dp < end; dp = next_extra(dp)) {
779 // No need for "OrderAccess::load_acquire" ops,
780 // since the data structure is monotonic.
781 if (dp->tag() == DataLayout::no_tag) break;
782 if (dp->tag() == DataLayout::arg_info_data_tag) {
783 dp = end; // ArgInfoData is at the end of extra data section.
784 break;
785 }
786 if (dp->bci() == bci) {
787 assert(dp->tag() == DataLayout::bit_data_tag, "sane");
788 return new BitData(dp);
789 }
790 }
791 if (create_if_missing && dp < end) {
792 // Allocate this one. There is no mutual exclusion,
793 // so two threads could allocate different BCIs to the
794 // same data layout. This means these extra data
795 // records, like most other MDO contents, must not be
796 // trusted too much.
797 DataLayout temp;
798 temp.initialize(DataLayout::bit_data_tag, bci, 0);
799 dp->release_set_header(temp.header());
800 assert(dp->tag() == DataLayout::bit_data_tag, "sane");
801 //NO: assert(dp->bci() == bci, "no concurrent allocation");
802 return new BitData(dp);
803 }
804 return NULL;
805 }
806
807 ArgInfoData *MethodData::arg_info() {
808 DataLayout* dp = extra_data_base();
809 DataLayout* end = extra_data_limit();
810 for (; dp < end; dp = next_extra(dp)) {
811 if (dp->tag() == DataLayout::arg_info_data_tag)
812 return new ArgInfoData(dp);
813 }
814 return NULL;
815 }
816
817 // Printing
818
819 #ifndef PRODUCT
820
821 void MethodData::print_on(outputStream* st) const {
822 assert(is_methodData(), "should be method data");
823 st->print("method data for ");
824 method()->print_value_on(st);
825 st->cr();
826 print_data_on(st);
827 }
828
829 #endif //PRODUCT
830
831 void MethodData::print_value_on(outputStream* st) const {
832 assert(is_methodData(), "should be method data");
833 st->print("method data for ");
834 method()->print_value_on(st);
835 }
836
837 #ifndef PRODUCT
838 void MethodData::print_data_on(outputStream* st) const {
839 ResourceMark rm;
840 ProfileData* data = first_data();
841 for ( ; is_valid(data); data = next_data(data)) {
842 st->print("%d", dp_to_di(data->dp()));
843 st->fill_to(6);
844 data->print_data_on(st);
845 }
846 st->print_cr("--- Extra data:");
847 DataLayout* dp = extra_data_base();
848 DataLayout* end = extra_data_limit();
849 for (; dp < end; dp = next_extra(dp)) {
850 // No need for "OrderAccess::load_acquire" ops,
851 // since the data structure is monotonic.
852 if (dp->tag() == DataLayout::no_tag) continue;
853 if (dp->tag() == DataLayout::bit_data_tag) {
854 data = new BitData(dp);
855 } else {
856 assert(dp->tag() == DataLayout::arg_info_data_tag, "must be BitData or ArgInfo");
857 data = new ArgInfoData(dp);
858 dp = end; // ArgInfoData is at the end of extra data section.
859 }
860 st->print("%d", dp_to_di(data->dp()));
861 st->fill_to(6);
862 data->print_data_on(st);
863 }
864 }
865 #endif
866
867 #if INCLUDE_SERVICES
868 // Size Statistics
869 void MethodData::collect_statistics(KlassSizeStats *sz) const {
870 int n = sz->count(this);
871 sz->_method_data_bytes += n;
872 sz->_method_all_bytes += n;
873 sz->_rw_bytes += n;
874 }
875 #endif // INCLUDE_SERVICES
876
877 // Verification
878
879 void MethodData::verify_on(outputStream* st) {
880 guarantee(is_methodData(), "object must be method data");
881 // guarantee(m->is_perm(), "should be in permspace");
882 this->verify_data_on(st);
883 }
884
885 void MethodData::verify_data_on(outputStream* st) {
886 NEEDS_CLEANUP;
887 // not yet implemented.
888 }