1 /*
2 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "interpreter/bytecodeStream.hpp"
27 #include "oops/generateOopMap.hpp"
28 #include "oops/oop.inline.hpp"
29 #include "oops/symbol.hpp"
30 #include "runtime/handles.inline.hpp"
31 #include "runtime/java.hpp"
32 #include "runtime/relocator.hpp"
33 #include "utilities/bitMap.inline.hpp"
34
35 //
36 //
37 // Compute stack layouts for each instruction in method.
38 //
39 // Problems:
40 // - What to do about jsr with different types of local vars?
41 // Need maps that are conditional on jsr path?
42 // - Jsr and exceptions should be done more efficiently (the retAddr stuff)
43 //
44 // Alternative:
45 // - Could extend verifier to provide this information.
46 // For: one fewer abstract interpreter to maintain. Against: the verifier
47 // solves a bigger problem so slower (undesirable to force verification of
48 // everything?).
49 //
50 // Algorithm:
51 // Partition bytecodes into basic blocks
52 // For each basic block: store entry state (vars, stack). For instructions
53 // inside basic blocks we do not store any state (instead we recompute it
54 // from state produced by previous instruction).
55 //
56 // Perform abstract interpretation of bytecodes over this lattice:
57 //
58 // _--'#'--_
59 // / / \ \
60 // / / \ \
61 // / | | \
62 // 'r' 'v' 'p' ' '
63 // \ | | /
64 // \ \ / /
65 // \ \ / /
66 // -- '@' --
67 //
68 // '#' top, result of conflict merge
69 // 'r' reference type
70 // 'v' value type
71 // 'p' pc type for jsr/ret
72 // ' ' uninitialized; never occurs on operand stack in Java
73 // '@' bottom/unexecuted; initial state each bytecode.
74 //
75 // Basic block headers are the only merge points. We use this iteration to
76 // compute the information:
77 //
78 // find basic blocks;
79 // initialize them with uninitialized state;
80 // initialize first BB according to method signature;
81 // mark first BB changed
82 // while (some BB is changed) do {
83 // perform abstract interpration of all bytecodes in BB;
84 // merge exit state of BB into entry state of all successor BBs,
85 // noting if any of these change;
86 // }
87 //
88 // One additional complication is necessary. The jsr instruction pushes
89 // a return PC on the stack (a 'p' type in the abstract interpretation).
90 // To be able to process "ret" bytecodes, we keep track of these return
91 // PC's in a 'retAddrs' structure in abstract interpreter context (when
92 // processing a "ret" bytecodes, it is not sufficient to know that it gets
93 // an argument of the right type 'p'; we need to know which address it
94 // returns to).
95 //
96 // (Note this comment is borrowed form the original author of the algorithm)
97
98 // ComputeCallStack
99 //
100 // Specialization of SignatureIterator - compute the effects of a call
101 //
102 class ComputeCallStack : public SignatureIterator {
103 CellTypeState *_effect;
104 int _idx;
105
106 void setup();
107 void set(CellTypeState state) { _effect[_idx++] = state; }
108 int length() { return _idx; };
109
110 virtual void do_bool () { set(CellTypeState::value); };
111 virtual void do_char () { set(CellTypeState::value); };
112 virtual void do_float () { set(CellTypeState::value); };
113 virtual void do_byte () { set(CellTypeState::value); };
114 virtual void do_short () { set(CellTypeState::value); };
115 virtual void do_int () { set(CellTypeState::value); };
116 virtual void do_void () { set(CellTypeState::bottom);};
117 virtual void do_object(int begin, int end) { set(CellTypeState::ref); };
118 virtual void do_array (int begin, int end) { set(CellTypeState::ref); };
119
120 void do_double() { set(CellTypeState::value);
121 set(CellTypeState::value); }
122 void do_long () { set(CellTypeState::value);
123 set(CellTypeState::value); }
124
125 public:
126 ComputeCallStack(Symbol* signature) : SignatureIterator(signature) {};
127
128 // Compute methods
129 int compute_for_parameters(bool is_static, CellTypeState *effect) {
130 _idx = 0;
131 _effect = effect;
132
133 if (!is_static)
134 effect[_idx++] = CellTypeState::ref;
135
136 iterate_parameters();
137
138 return length();
139 };
140
141 int compute_for_returntype(CellTypeState *effect) {
142 _idx = 0;
143 _effect = effect;
144 iterate_returntype();
145 set(CellTypeState::bottom); // Always terminate with a bottom state, so ppush works
146
147 return length();
148 }
149 };
150
151 //=========================================================================================
152 // ComputeEntryStack
153 //
154 // Specialization of SignatureIterator - in order to set up first stack frame
155 //
156 class ComputeEntryStack : public SignatureIterator {
157 CellTypeState *_effect;
158 int _idx;
159
160 void setup();
161 void set(CellTypeState state) { _effect[_idx++] = state; }
162 int length() { return _idx; };
163
164 virtual void do_bool () { set(CellTypeState::value); };
165 virtual void do_char () { set(CellTypeState::value); };
166 virtual void do_float () { set(CellTypeState::value); };
167 virtual void do_byte () { set(CellTypeState::value); };
168 virtual void do_short () { set(CellTypeState::value); };
169 virtual void do_int () { set(CellTypeState::value); };
170 virtual void do_void () { set(CellTypeState::bottom);};
171 virtual void do_object(int begin, int end) { set(CellTypeState::make_slot_ref(_idx)); }
172 virtual void do_array (int begin, int end) { set(CellTypeState::make_slot_ref(_idx)); }
173
174 void do_double() { set(CellTypeState::value);
175 set(CellTypeState::value); }
176 void do_long () { set(CellTypeState::value);
177 set(CellTypeState::value); }
178
179 public:
180 ComputeEntryStack(Symbol* signature) : SignatureIterator(signature) {};
181
182 // Compute methods
183 int compute_for_parameters(bool is_static, CellTypeState *effect) {
184 _idx = 0;
185 _effect = effect;
186
187 if (!is_static)
188 effect[_idx++] = CellTypeState::make_slot_ref(0);
189
190 iterate_parameters();
191
192 return length();
193 };
194
195 int compute_for_returntype(CellTypeState *effect) {
196 _idx = 0;
197 _effect = effect;
198 iterate_returntype();
199 set(CellTypeState::bottom); // Always terminate with a bottom state, so ppush works
200
201 return length();
202 }
203 };
204
205 //=====================================================================================
206 //
207 // Implementation of RetTable/RetTableEntry
208 //
209 // Contains function to itereate through all bytecodes
210 // and find all return entry points
211 //
212 int RetTable::_init_nof_entries = 10;
213 int RetTableEntry::_init_nof_jsrs = 5;
214
215 void RetTableEntry::add_delta(int bci, int delta) {
216 if (_target_bci > bci) _target_bci += delta;
217
218 for (int k = 0; k < _jsrs->length(); k++) {
219 int jsr = _jsrs->at(k);
220 if (jsr > bci) _jsrs->at_put(k, jsr+delta);
221 }
222 }
223
224 void RetTable::compute_ret_table(methodHandle method) {
225 BytecodeStream i(method);
226 Bytecodes::Code bytecode;
227
228 while( (bytecode = i.next()) >= 0) {
229 switch (bytecode) {
230 case Bytecodes::_jsr:
231 add_jsr(i.next_bci(), i.dest());
232 break;
233 case Bytecodes::_jsr_w:
234 add_jsr(i.next_bci(), i.dest_w());
235 break;
236 }
237 }
238 }
239
240 void RetTable::add_jsr(int return_bci, int target_bci) {
241 RetTableEntry* entry = _first;
242
243 // Scan table for entry
244 for (;entry && entry->target_bci() != target_bci; entry = entry->next());
245
246 if (!entry) {
247 // Allocate new entry and put in list
248 entry = new RetTableEntry(target_bci, _first);
249 _first = entry;
250 }
251
252 // Now "entry" is set. Make sure that the entry is initialized
253 // and has room for the new jsr.
254 entry->add_jsr(return_bci);
255 }
256
257 RetTableEntry* RetTable::find_jsrs_for_target(int targBci) {
258 RetTableEntry *cur = _first;
259
260 while(cur) {
261 assert(cur->target_bci() != -1, "sanity check");
262 if (cur->target_bci() == targBci) return cur;
263 cur = cur->next();
264 }
265 ShouldNotReachHere();
266 return NULL;
267 }
268
269 // The instruction at bci is changing size by "delta". Update the return map.
270 void RetTable::update_ret_table(int bci, int delta) {
271 RetTableEntry *cur = _first;
272 while(cur) {
273 cur->add_delta(bci, delta);
274 cur = cur->next();
275 }
276 }
277
278 //
279 // Celltype state
280 //
281
282 CellTypeState CellTypeState::bottom = CellTypeState::make_bottom();
283 CellTypeState CellTypeState::uninit = CellTypeState::make_any(uninit_value);
284 CellTypeState CellTypeState::ref = CellTypeState::make_any(ref_conflict);
285 CellTypeState CellTypeState::value = CellTypeState::make_any(val_value);
286 CellTypeState CellTypeState::refUninit = CellTypeState::make_any(ref_conflict | uninit_value);
287 CellTypeState CellTypeState::top = CellTypeState::make_top();
288 CellTypeState CellTypeState::addr = CellTypeState::make_any(addr_conflict);
289
290 // Commonly used constants
291 static CellTypeState epsilonCTS[1] = { CellTypeState::bottom };
292 static CellTypeState refCTS = CellTypeState::ref;
293 static CellTypeState valCTS = CellTypeState::value;
294 static CellTypeState vCTS[2] = { CellTypeState::value, CellTypeState::bottom };
295 static CellTypeState rCTS[2] = { CellTypeState::ref, CellTypeState::bottom };
296 static CellTypeState rrCTS[3] = { CellTypeState::ref, CellTypeState::ref, CellTypeState::bottom };
297 static CellTypeState vrCTS[3] = { CellTypeState::value, CellTypeState::ref, CellTypeState::bottom };
298 static CellTypeState vvCTS[3] = { CellTypeState::value, CellTypeState::value, CellTypeState::bottom };
299 static CellTypeState rvrCTS[4] = { CellTypeState::ref, CellTypeState::value, CellTypeState::ref, CellTypeState::bottom };
300 static CellTypeState vvrCTS[4] = { CellTypeState::value, CellTypeState::value, CellTypeState::ref, CellTypeState::bottom };
301 static CellTypeState vvvCTS[4] = { CellTypeState::value, CellTypeState::value, CellTypeState::value, CellTypeState::bottom };
302 static CellTypeState vvvrCTS[5] = { CellTypeState::value, CellTypeState::value, CellTypeState::value, CellTypeState::ref, CellTypeState::bottom };
303 static CellTypeState vvvvCTS[5] = { CellTypeState::value, CellTypeState::value, CellTypeState::value, CellTypeState::value, CellTypeState::bottom };
304
305 char CellTypeState::to_char() const {
306 if (can_be_reference()) {
307 if (can_be_value() || can_be_address())
308 return '#'; // Conflict that needs to be rewritten
309 else
310 return 'r';
311 } else if (can_be_value())
312 return 'v';
313 else if (can_be_address())
314 return 'p';
315 else if (can_be_uninit())
316 return ' ';
317 else
318 return '@';
319 }
320
321
322 // Print a detailed CellTypeState. Indicate all bits that are set. If
323 // the CellTypeState represents an address or a reference, print the
324 // value of the additional information.
325 void CellTypeState::print(outputStream *os) {
326 if (can_be_address()) {
327 os->print("(p");
328 } else {
329 os->print("( ");
330 }
331 if (can_be_reference()) {
332 os->print("r");
333 } else {
334 os->print(" ");
335 }
336 if (can_be_value()) {
337 os->print("v");
338 } else {
339 os->print(" ");
340 }
341 if (can_be_uninit()) {
342 os->print("u|");
343 } else {
344 os->print(" |");
345 }
346 if (is_info_top()) {
347 os->print("Top)");
348 } else if (is_info_bottom()) {
349 os->print("Bot)");
350 } else {
351 if (is_reference()) {
352 int info = get_info();
353 int data = info & ~(ref_not_lock_bit | ref_slot_bit);
354 if (info & ref_not_lock_bit) {
355 // Not a monitor lock reference.
356 if (info & ref_slot_bit) {
357 // slot
358 os->print("slot%d)", data);
359 } else {
360 // line
361 os->print("line%d)", data);
362 }
363 } else {
364 // lock
365 os->print("lock%d)", data);
366 }
367 } else {
368 os->print("%d)", get_info());
369 }
370 }
371 }
372
373 //
374 // Basicblock handling methods
375 //
376
377 void GenerateOopMap ::initialize_bb() {
378 _gc_points = 0;
379 _bb_count = 0;
380 _bb_hdr_bits.clear();
381 _bb_hdr_bits.resize(method()->code_size());
382 }
383
384 void GenerateOopMap::bb_mark_fct(GenerateOopMap *c, int bci, int *data) {
385 assert(bci>= 0 && bci < c->method()->code_size(), "index out of bounds");
386 if (c->is_bb_header(bci))
387 return;
388
389 if (TraceNewOopMapGeneration) {
390 tty->print_cr("Basicblock#%d begins at: %d", c->_bb_count, bci);
391 }
392 c->set_bbmark_bit(bci);
393 c->_bb_count++;
394 }
395
396
397 void GenerateOopMap::mark_bbheaders_and_count_gc_points() {
398 initialize_bb();
399
400 bool fellThrough = false; // False to get first BB marked.
401
402 // First mark all exception handlers as start of a basic-block
403 ExceptionTable excps(method());
404 for(int i = 0; i < excps.length(); i ++) {
405 bb_mark_fct(this, excps.handler_pc(i), NULL);
406 }
407
408 // Then iterate through the code
409 BytecodeStream bcs(_method);
410 Bytecodes::Code bytecode;
411
412 while( (bytecode = bcs.next()) >= 0) {
413 int bci = bcs.bci();
414
415 if (!fellThrough)
416 bb_mark_fct(this, bci, NULL);
417
418 fellThrough = jump_targets_do(&bcs, &GenerateOopMap::bb_mark_fct, NULL);
419
420 /* We will also mark successors of jsr's as basic block headers. */
421 switch (bytecode) {
422 case Bytecodes::_jsr:
423 assert(!fellThrough, "should not happen");
424 bb_mark_fct(this, bci + Bytecodes::length_for(bytecode), NULL);
425 break;
426 case Bytecodes::_jsr_w:
427 assert(!fellThrough, "should not happen");
428 bb_mark_fct(this, bci + Bytecodes::length_for(bytecode), NULL);
429 break;
430 }
431
432 if (possible_gc_point(&bcs))
433 _gc_points++;
434 }
435 }
436
437 void GenerateOopMap::reachable_basicblock(GenerateOopMap *c, int bci, int *data) {
438 assert(bci>= 0 && bci < c->method()->code_size(), "index out of bounds");
439 BasicBlock* bb = c->get_basic_block_at(bci);
440 if (bb->is_dead()) {
441 bb->mark_as_alive();
442 *data = 1; // Mark basicblock as changed
443 }
444 }
445
446
447 void GenerateOopMap::mark_reachable_code() {
448 int change = 1; // int to get function pointers to work
449
450 // Mark entry basic block as alive and all exception handlers
451 _basic_blocks[0].mark_as_alive();
452 ExceptionTable excps(method());
453 for(int i = 0; i < excps.length(); i++) {
454 BasicBlock *bb = get_basic_block_at(excps.handler_pc(i));
455 // If block is not already alive (due to multiple exception handlers to same bb), then
456 // make it alive
457 if (bb->is_dead()) bb->mark_as_alive();
458 }
459
460 BytecodeStream bcs(_method);
461
462 // Iterate through all basic blocks until we reach a fixpoint
463 while (change) {
464 change = 0;
465
466 for (int i = 0; i < _bb_count; i++) {
467 BasicBlock *bb = &_basic_blocks[i];
468 if (bb->is_alive()) {
469 // Position bytecodestream at last bytecode in basicblock
470 bcs.set_start(bb->_end_bci);
471 bcs.next();
472 Bytecodes::Code bytecode = bcs.code();
473 int bci = bcs.bci();
474 assert(bci == bb->_end_bci, "wrong bci");
475
476 bool fell_through = jump_targets_do(&bcs, &GenerateOopMap::reachable_basicblock, &change);
477
478 // We will also mark successors of jsr's as alive.
479 switch (bytecode) {
480 case Bytecodes::_jsr:
481 case Bytecodes::_jsr_w:
482 assert(!fell_through, "should not happen");
483 reachable_basicblock(this, bci + Bytecodes::length_for(bytecode), &change);
484 break;
485 }
486 if (fell_through) {
487 // Mark successor as alive
488 if (bb[1].is_dead()) {
489 bb[1].mark_as_alive();
490 change = 1;
491 }
492 }
493 }
494 }
495 }
496 }
497
498 /* If the current instruction in "c" has no effect on control flow,
499 returns "true". Otherwise, calls "jmpFct" one or more times, with
500 "c", an appropriate "pcDelta", and "data" as arguments, then
501 returns "false". There is one exception: if the current
502 instruction is a "ret", returns "false" without calling "jmpFct".
503 Arrangements for tracking the control flow of a "ret" must be made
504 externally. */
505 bool GenerateOopMap::jump_targets_do(BytecodeStream *bcs, jmpFct_t jmpFct, int *data) {
506 int bci = bcs->bci();
507
508 switch (bcs->code()) {
509 case Bytecodes::_ifeq:
510 case Bytecodes::_ifne:
511 case Bytecodes::_iflt:
512 case Bytecodes::_ifge:
513 case Bytecodes::_ifgt:
514 case Bytecodes::_ifle:
515 case Bytecodes::_if_icmpeq:
516 case Bytecodes::_if_icmpne:
517 case Bytecodes::_if_icmplt:
518 case Bytecodes::_if_icmpge:
519 case Bytecodes::_if_icmpgt:
520 case Bytecodes::_if_icmple:
521 case Bytecodes::_if_acmpeq:
522 case Bytecodes::_if_acmpne:
523 case Bytecodes::_ifnull:
524 case Bytecodes::_ifnonnull:
525 (*jmpFct)(this, bcs->dest(), data);
526 (*jmpFct)(this, bci + 3, data);
527 break;
528
529 case Bytecodes::_goto:
530 (*jmpFct)(this, bcs->dest(), data);
531 break;
532 case Bytecodes::_goto_w:
533 (*jmpFct)(this, bcs->dest_w(), data);
534 break;
535 case Bytecodes::_tableswitch:
536 { Bytecode_tableswitch tableswitch(method(), bcs->bcp());
537 int len = tableswitch.length();
538
539 (*jmpFct)(this, bci + tableswitch.default_offset(), data); /* Default. jump address */
540 while (--len >= 0) {
541 (*jmpFct)(this, bci + tableswitch.dest_offset_at(len), data);
542 }
543 break;
544 }
545
546 case Bytecodes::_lookupswitch:
547 { Bytecode_lookupswitch lookupswitch(method(), bcs->bcp());
548 int npairs = lookupswitch.number_of_pairs();
549 (*jmpFct)(this, bci + lookupswitch.default_offset(), data); /* Default. */
550 while(--npairs >= 0) {
551 LookupswitchPair pair = lookupswitch.pair_at(npairs);
552 (*jmpFct)(this, bci + pair.offset(), data);
553 }
554 break;
555 }
556 case Bytecodes::_jsr:
557 assert(bcs->is_wide()==false, "sanity check");
558 (*jmpFct)(this, bcs->dest(), data);
559
560
561
562 break;
563 case Bytecodes::_jsr_w:
564 (*jmpFct)(this, bcs->dest_w(), data);
565 break;
566 case Bytecodes::_wide:
567 ShouldNotReachHere();
568 return true;
569 break;
570 case Bytecodes::_athrow:
571 case Bytecodes::_ireturn:
572 case Bytecodes::_lreturn:
573 case Bytecodes::_freturn:
574 case Bytecodes::_dreturn:
575 case Bytecodes::_areturn:
576 case Bytecodes::_return:
577 case Bytecodes::_ret:
578 break;
579 default:
580 return true;
581 }
582 return false;
583 }
584
585 /* Requires "pc" to be the head of a basic block; returns that basic
586 block. */
587 BasicBlock *GenerateOopMap::get_basic_block_at(int bci) const {
588 BasicBlock* bb = get_basic_block_containing(bci);
589 assert(bb->_bci == bci, "should have found BB");
590 return bb;
591 }
592
593 // Requires "pc" to be the start of an instruction; returns the basic
594 // block containing that instruction. */
595 BasicBlock *GenerateOopMap::get_basic_block_containing(int bci) const {
596 BasicBlock *bbs = _basic_blocks;
597 int lo = 0, hi = _bb_count - 1;
598
599 while (lo <= hi) {
600 int m = (lo + hi) / 2;
601 int mbci = bbs[m]._bci;
602 int nbci;
603
604 if ( m == _bb_count-1) {
605 assert( bci >= mbci && bci < method()->code_size(), "sanity check failed");
606 return bbs+m;
607 } else {
608 nbci = bbs[m+1]._bci;
609 }
610
611 if ( mbci <= bci && bci < nbci) {
612 return bbs+m;
613 } else if (mbci < bci) {
614 lo = m + 1;
615 } else {
616 assert(mbci > bci, "sanity check");
617 hi = m - 1;
618 }
619 }
620
621 fatal("should have found BB");
622 return NULL;
623 }
624
625 void GenerateOopMap::restore_state(BasicBlock *bb)
626 {
627 memcpy(_state, bb->_state, _state_len*sizeof(CellTypeState));
628 _stack_top = bb->_stack_top;
629 _monitor_top = bb->_monitor_top;
630 }
631
632 int GenerateOopMap::next_bb_start_pc(BasicBlock *bb) {
633 int bbNum = bb - _basic_blocks + 1;
634 if (bbNum == _bb_count)
635 return method()->code_size();
636
637 return _basic_blocks[bbNum]._bci;
638 }
639
640 //
641 // CellType handling methods
642 //
643
644 void GenerateOopMap::init_state() {
645 _state_len = _max_locals + _max_stack + _max_monitors;
646 _state = NEW_RESOURCE_ARRAY(CellTypeState, _state_len);
647 memset(_state, 0, _state_len * sizeof(CellTypeState));
648 _state_vec_buf = NEW_RESOURCE_ARRAY(char, MAX3(_max_locals, _max_stack, _max_monitors) + 1/*for null terminator char */);
649 }
650
651 void GenerateOopMap::make_context_uninitialized() {
652 CellTypeState* vs = vars();
653
654 for (int i = 0; i < _max_locals; i++)
655 vs[i] = CellTypeState::uninit;
656
657 _stack_top = 0;
658 _monitor_top = 0;
659 }
660
661 int GenerateOopMap::methodsig_to_effect(Symbol* signature, bool is_static, CellTypeState* effect) {
662 ComputeEntryStack ces(signature);
663 return ces.compute_for_parameters(is_static, effect);
664 }
665
666 // Return result of merging cts1 and cts2.
667 CellTypeState CellTypeState::merge(CellTypeState cts, int slot) const {
668 CellTypeState result;
669
670 assert(!is_bottom() && !cts.is_bottom(),
671 "merge of bottom values is handled elsewhere");
672
673 result._state = _state | cts._state;
674
675 // If the top bit is set, we don't need to do any more work.
676 if (!result.is_info_top()) {
677 assert((result.can_be_address() || result.can_be_reference()),
678 "only addresses and references have non-top info");
679
680 if (!equal(cts)) {
681 // The two values being merged are different. Raise to top.
682 if (result.is_reference()) {
683 result = CellTypeState::make_slot_ref(slot);
684 } else {
685 result._state |= info_conflict;
686 }
687 }
688 }
689 assert(result.is_valid_state(), "checking that CTS merge maintains legal state");
690
691 return result;
692 }
693
694 // Merge the variable state for locals and stack from cts into bbts.
695 bool GenerateOopMap::merge_local_state_vectors(CellTypeState* cts,
696 CellTypeState* bbts) {
697 int i;
698 int len = _max_locals + _stack_top;
699 bool change = false;
700
701 for (i = len - 1; i >= 0; i--) {
702 CellTypeState v = cts[i].merge(bbts[i], i);
703 change = change || !v.equal(bbts[i]);
704 bbts[i] = v;
705 }
706
707 return change;
708 }
709
710 // Merge the monitor stack state from cts into bbts.
711 bool GenerateOopMap::merge_monitor_state_vectors(CellTypeState* cts,
712 CellTypeState* bbts) {
713 bool change = false;
714 if (_max_monitors > 0 && _monitor_top != bad_monitors) {
715 // If there are no monitors in the program, or there has been
716 // a monitor matching error before this point in the program,
717 // then we do not merge in the monitor state.
718
719 int base = _max_locals + _max_stack;
720 int len = base + _monitor_top;
721 for (int i = len - 1; i >= base; i--) {
722 CellTypeState v = cts[i].merge(bbts[i], i);
723
724 // Can we prove that, when there has been a change, it will already
725 // have been detected at this point? That would make this equal
726 // check here unnecessary.
727 change = change || !v.equal(bbts[i]);
728 bbts[i] = v;
729 }
730 }
731
732 return change;
733 }
734
735 void GenerateOopMap::copy_state(CellTypeState *dst, CellTypeState *src) {
736 int len = _max_locals + _stack_top;
737 for (int i = 0; i < len; i++) {
738 if (src[i].is_nonlock_reference()) {
739 dst[i] = CellTypeState::make_slot_ref(i);
740 } else {
741 dst[i] = src[i];
742 }
743 }
744 if (_max_monitors > 0 && _monitor_top != bad_monitors) {
745 int base = _max_locals + _max_stack;
746 len = base + _monitor_top;
747 for (int i = base; i < len; i++) {
748 dst[i] = src[i];
749 }
750 }
751 }
752
753
754 // Merge the states for the current block and the next. As long as a
755 // block is reachable the locals and stack must be merged. If the
756 // stack heights don't match then this is a verification error and
757 // it's impossible to interpret the code. Simultaneously monitor
758 // states are being check to see if they nest statically. If monitor
759 // depths match up then their states are merged. Otherwise the
760 // mismatch is simply recorded and interpretation continues since
761 // monitor matching is purely informational and doesn't say anything
762 // about the correctness of the code.
763 void GenerateOopMap::merge_state_into_bb(BasicBlock *bb) {
764 assert(bb->is_alive(), "merging state into a dead basicblock");
765
766 if (_stack_top == bb->_stack_top) {
767 // always merge local state even if monitors don't match.
768 if (merge_local_state_vectors(_state, bb->_state)) {
769 bb->set_changed(true);
770 }
771 if (_monitor_top == bb->_monitor_top) {
772 // monitors still match so continue merging monitor states.
773 if (merge_monitor_state_vectors(_state, bb->_state)) {
774 bb->set_changed(true);
775 }
776 } else {
777 if (TraceMonitorMismatch) {
778 report_monitor_mismatch("monitor stack height merge conflict");
779 }
780 // When the monitor stacks are not matched, we set _monitor_top to
781 // bad_monitors. This signals that, from here on, the monitor stack cannot
782 // be trusted. In particular, monitorexit bytecodes may throw
783 // exceptions. We mark this block as changed so that the change
784 // propagates properly.
785 bb->_monitor_top = bad_monitors;
786 bb->set_changed(true);
787 _monitor_safe = false;
788 }
789 } else if (!bb->is_reachable()) {
790 // First time we look at this BB
791 copy_state(bb->_state, _state);
792 bb->_stack_top = _stack_top;
793 bb->_monitor_top = _monitor_top;
794 bb->set_changed(true);
795 } else {
796 verify_error("stack height conflict: %d vs. %d", _stack_top, bb->_stack_top);
797 }
798 }
799
800 void GenerateOopMap::merge_state(GenerateOopMap *gom, int bci, int* data) {
801 gom->merge_state_into_bb(gom->get_basic_block_at(bci));
802 }
803
804 void GenerateOopMap::set_var(int localNo, CellTypeState cts) {
805 assert(cts.is_reference() || cts.is_value() || cts.is_address(),
806 "wrong celltypestate");
807 if (localNo < 0 || localNo > _max_locals) {
808 verify_error("variable write error: r%d", localNo);
809 return;
810 }
811 vars()[localNo] = cts;
812 }
813
814 CellTypeState GenerateOopMap::get_var(int localNo) {
815 assert(localNo < _max_locals + _nof_refval_conflicts, "variable read error");
816 if (localNo < 0 || localNo > _max_locals) {
817 verify_error("variable read error: r%d", localNo);
818 return valCTS; // just to pick something;
819 }
820 return vars()[localNo];
821 }
822
823 CellTypeState GenerateOopMap::pop() {
824 if ( _stack_top <= 0) {
825 verify_error("stack underflow");
826 return valCTS; // just to pick something
827 }
828 return stack()[--_stack_top];
829 }
830
831 void GenerateOopMap::push(CellTypeState cts) {
832 if ( _stack_top >= _max_stack) {
833 verify_error("stack overflow");
834 return;
835 }
836 stack()[_stack_top++] = cts;
837 }
838
839 CellTypeState GenerateOopMap::monitor_pop() {
840 assert(_monitor_top != bad_monitors, "monitor_pop called on error monitor stack");
841 if (_monitor_top == 0) {
842 // We have detected a pop of an empty monitor stack.
843 _monitor_safe = false;
844 _monitor_top = bad_monitors;
845
846 if (TraceMonitorMismatch) {
847 report_monitor_mismatch("monitor stack underflow");
848 }
849 return CellTypeState::ref; // just to keep the analysis going.
850 }
851 return monitors()[--_monitor_top];
852 }
853
854 void GenerateOopMap::monitor_push(CellTypeState cts) {
855 assert(_monitor_top != bad_monitors, "monitor_push called on error monitor stack");
856 if (_monitor_top >= _max_monitors) {
857 // Some monitorenter is being executed more than once.
858 // This means that the monitor stack cannot be simulated.
859 _monitor_safe = false;
860 _monitor_top = bad_monitors;
861
862 if (TraceMonitorMismatch) {
863 report_monitor_mismatch("monitor stack overflow");
864 }
865 return;
866 }
867 monitors()[_monitor_top++] = cts;
868 }
869
870 //
871 // Interpretation handling methods
872 //
873
874 void GenerateOopMap::do_interpretation()
875 {
876 // "i" is just for debugging, so we can detect cases where this loop is
877 // iterated more than once.
878 int i = 0;
879 do {
880 #ifndef PRODUCT
881 if (TraceNewOopMapGeneration) {
882 tty->print("\n\nIteration #%d of do_interpretation loop, method:\n", i);
883 method()->print_name(tty);
884 tty->print("\n\n");
885 }
886 #endif
887 _conflict = false;
888 _monitor_safe = true;
889 // init_state is now called from init_basic_blocks. The length of a
890 // state vector cannot be determined until we have made a pass through
891 // the bytecodes counting the possible monitor entries.
892 if (!_got_error) init_basic_blocks();
893 if (!_got_error) setup_method_entry_state();
894 if (!_got_error) interp_all();
895 if (!_got_error) rewrite_refval_conflicts();
896 i++;
897 } while (_conflict && !_got_error);
898 }
899
900 void GenerateOopMap::init_basic_blocks() {
901 // Note: Could consider reserving only the needed space for each BB's state
902 // (entry stack may not be of maximal height for every basic block).
903 // But cumbersome since we don't know the stack heights yet. (Nor the
904 // monitor stack heights...)
905
906 _basic_blocks = NEW_RESOURCE_ARRAY(BasicBlock, _bb_count);
907
908 // Make a pass through the bytecodes. Count the number of monitorenters.
909 // This can be used an upper bound on the monitor stack depth in programs
910 // which obey stack discipline with their monitor usage. Initialize the
911 // known information about basic blocks.
912 BytecodeStream j(_method);
913 Bytecodes::Code bytecode;
914
915 int bbNo = 0;
916 int monitor_count = 0;
917 int prev_bci = -1;
918 while( (bytecode = j.next()) >= 0) {
919 if (j.code() == Bytecodes::_monitorenter) {
920 monitor_count++;
921 }
922
923 int bci = j.bci();
924 if (is_bb_header(bci)) {
925 // Initialize the basicblock structure
926 BasicBlock *bb = _basic_blocks + bbNo;
927 bb->_bci = bci;
928 bb->_max_locals = _max_locals;
929 bb->_max_stack = _max_stack;
930 bb->set_changed(false);
931 bb->_stack_top = BasicBlock::_dead_basic_block; // Initialize all basicblocks are dead.
932 bb->_monitor_top = bad_monitors;
933
934 if (bbNo > 0) {
935 _basic_blocks[bbNo - 1]._end_bci = prev_bci;
936 }
937
938 bbNo++;
939 }
940 // Remember prevous bci.
941 prev_bci = bci;
942 }
943 // Set
944 _basic_blocks[bbNo-1]._end_bci = prev_bci;
945
946
947 // Check that the correct number of basicblocks was found
948 if (bbNo !=_bb_count) {
949 if (bbNo < _bb_count) {
950 verify_error("jump into the middle of instruction?");
951 return;
952 } else {
953 verify_error("extra basic blocks - should not happen?");
954 return;
955 }
956 }
957
958 _max_monitors = monitor_count;
959
960 // Now that we have a bound on the depth of the monitor stack, we can
961 // initialize the CellTypeState-related information.
962 init_state();
963
964 // We allocate space for all state-vectors for all basicblocks in one huge
965 // chunk. Then in the next part of the code, we set a pointer in each
966 // _basic_block that points to each piece.
967
968 // The product of bbNo and _state_len can get large if there are lots of
969 // basic blocks and stack/locals/monitors. Need to check to make sure
970 // we don't overflow the capacity of a pointer.
971 if ((unsigned)bbNo > UINTPTR_MAX / sizeof(CellTypeState) / _state_len) {
972 report_error("The amount of memory required to analyze this method "
973 "exceeds addressable range");
974 return;
975 }
976
977 CellTypeState *basicBlockState =
978 NEW_RESOURCE_ARRAY(CellTypeState, bbNo * _state_len);
979 memset(basicBlockState, 0, bbNo * _state_len * sizeof(CellTypeState));
980
981 // Make a pass over the basicblocks and assign their state vectors.
982 for (int blockNum=0; blockNum < bbNo; blockNum++) {
983 BasicBlock *bb = _basic_blocks + blockNum;
984 bb->_state = basicBlockState + blockNum * _state_len;
985
986 #ifdef ASSERT
987 if (blockNum + 1 < bbNo) {
988 address bcp = _method->bcp_from(bb->_end_bci);
989 int bc_len = Bytecodes::java_length_at(_method(), bcp);
990 assert(bb->_end_bci + bc_len == bb[1]._bci, "unmatched bci info in basicblock");
991 }
992 #endif
993 }
994 #ifdef ASSERT
995 { BasicBlock *bb = &_basic_blocks[bbNo-1];
996 address bcp = _method->bcp_from(bb->_end_bci);
997 int bc_len = Bytecodes::java_length_at(_method(), bcp);
998 assert(bb->_end_bci + bc_len == _method->code_size(), "wrong end bci");
999 }
1000 #endif
1001
1002 // Mark all alive blocks
1003 mark_reachable_code();
1004 }
1005
1006 void GenerateOopMap::setup_method_entry_state() {
1007
1008 // Initialize all locals to 'uninit' and set stack-height to 0
1009 make_context_uninitialized();
1010
1011 // Initialize CellState type of arguments
1012 methodsig_to_effect(method()->signature(), method()->is_static(), vars());
1013
1014 // If some references must be pre-assigned to null, then set that up
1015 initialize_vars();
1016
1017 // This is the start state
1018 merge_state_into_bb(&_basic_blocks[0]);
1019
1020 assert(_basic_blocks[0].changed(), "we are not getting off the ground");
1021 }
1022
1023 // The instruction at bci is changing size by "delta". Update the basic blocks.
1024 void GenerateOopMap::update_basic_blocks(int bci, int delta,
1025 int new_method_size) {
1026 assert(new_method_size >= method()->code_size() + delta,
1027 "new method size is too small");
1028
1029 BitMap::bm_word_t* new_bb_hdr_bits =
1030 NEW_RESOURCE_ARRAY(BitMap::bm_word_t,
1031 BitMap::word_align_up(new_method_size));
1032 _bb_hdr_bits.set_map(new_bb_hdr_bits);
1033 _bb_hdr_bits.set_size(new_method_size);
1034 _bb_hdr_bits.clear();
1035
1036
1037 for(int k = 0; k < _bb_count; k++) {
1038 if (_basic_blocks[k]._bci > bci) {
1039 _basic_blocks[k]._bci += delta;
1040 _basic_blocks[k]._end_bci += delta;
1041 }
1042 _bb_hdr_bits.at_put(_basic_blocks[k]._bci, true);
1043 }
1044 }
1045
1046 //
1047 // Initvars handling
1048 //
1049
1050 void GenerateOopMap::initialize_vars() {
1051 for (int k = 0; k < _init_vars->length(); k++)
1052 _state[_init_vars->at(k)] = CellTypeState::make_slot_ref(k);
1053 }
1054
1055 void GenerateOopMap::add_to_ref_init_set(int localNo) {
1056
1057 if (TraceNewOopMapGeneration)
1058 tty->print_cr("Added init vars: %d", localNo);
1059
1060 // Is it already in the set?
1061 if (_init_vars->contains(localNo) )
1062 return;
1063
1064 _init_vars->append(localNo);
1065 }
1066
1067 //
1068 // Interpreration code
1069 //
1070
1071 void GenerateOopMap::interp_all() {
1072 bool change = true;
1073
1074 while (change && !_got_error) {
1075 change = false;
1076 for (int i = 0; i < _bb_count && !_got_error; i++) {
1077 BasicBlock *bb = &_basic_blocks[i];
1078 if (bb->changed()) {
1079 if (_got_error) return;
1080 change = true;
1081 bb->set_changed(false);
1082 interp_bb(bb);
1083 }
1084 }
1085 }
1086 }
1087
1088 void GenerateOopMap::interp_bb(BasicBlock *bb) {
1089
1090 // We do not want to do anything in case the basic-block has not been initialized. This
1091 // will happen in the case where there is dead-code hang around in a method.
1092 assert(bb->is_reachable(), "should be reachable or deadcode exist");
1093 restore_state(bb);
1094
1095 BytecodeStream itr(_method);
1096
1097 // Set iterator interval to be the current basicblock
1098 int lim_bci = next_bb_start_pc(bb);
1099 itr.set_interval(bb->_bci, lim_bci);
1100 assert(lim_bci != bb->_bci, "must be at least one instruction in a basicblock");
1101 itr.next(); // read first instruction
1102
1103 // Iterates through all bytecodes except the last in a basic block.
1104 // We handle the last one special, since there is controlflow change.
1105 while(itr.next_bci() < lim_bci && !_got_error) {
1106 if (_has_exceptions || _monitor_top != 0) {
1107 // We do not need to interpret the results of exceptional
1108 // continuation from this instruction when the method has no
1109 // exception handlers and the monitor stack is currently
1110 // empty.
1111 do_exception_edge(&itr);
1112 }
1113 interp1(&itr);
1114 itr.next();
1115 }
1116
1117 // Handle last instruction.
1118 if (!_got_error) {
1119 assert(itr.next_bci() == lim_bci, "must point to end");
1120 if (_has_exceptions || _monitor_top != 0) {
1121 do_exception_edge(&itr);
1122 }
1123 interp1(&itr);
1124
1125 bool fall_through = jump_targets_do(&itr, GenerateOopMap::merge_state, NULL);
1126 if (_got_error) return;
1127
1128 if (itr.code() == Bytecodes::_ret) {
1129 assert(!fall_through, "cannot be set if ret instruction");
1130 // Automatically handles 'wide' ret indicies
1131 ret_jump_targets_do(&itr, GenerateOopMap::merge_state, itr.get_index(), NULL);
1132 } else if (fall_through) {
1133 // Hit end of BB, but the instr. was a fall-through instruction,
1134 // so perform transition as if the BB ended in a "jump".
1135 if (lim_bci != bb[1]._bci) {
1136 verify_error("bytecodes fell through last instruction");
1137 return;
1138 }
1139 merge_state_into_bb(bb + 1);
1140 }
1141 }
1142 }
1143
1144 void GenerateOopMap::do_exception_edge(BytecodeStream* itr) {
1145 // Only check exception edge, if bytecode can trap
1146 if (!Bytecodes::can_trap(itr->code())) return;
1147 switch (itr->code()) {
1148 case Bytecodes::_aload_0:
1149 // These bytecodes can trap for rewriting. We need to assume that
1150 // they do not throw exceptions to make the monitor analysis work.
1151 return;
1152
1153 case Bytecodes::_ireturn:
1154 case Bytecodes::_lreturn:
1155 case Bytecodes::_freturn:
1156 case Bytecodes::_dreturn:
1157 case Bytecodes::_areturn:
1158 case Bytecodes::_return:
1159 // If the monitor stack height is not zero when we leave the method,
1160 // then we are either exiting with a non-empty stack or we have
1161 // found monitor trouble earlier in our analysis. In either case,
1162 // assume an exception could be taken here.
1163 if (_monitor_top == 0) {
1164 return;
1165 }
1166 break;
1167
1168 case Bytecodes::_monitorexit:
1169 // If the monitor stack height is bad_monitors, then we have detected a
1170 // monitor matching problem earlier in the analysis. If the
1171 // monitor stack height is 0, we are about to pop a monitor
1172 // off of an empty stack. In either case, the bytecode
1173 // could throw an exception.
1174 if (_monitor_top != bad_monitors && _monitor_top != 0) {
1175 return;
1176 }
1177 break;
1178 }
1179
1180 if (_has_exceptions) {
1181 int bci = itr->bci();
1182 ExceptionTable exct(method());
1183 for(int i = 0; i< exct.length(); i++) {
1184 int start_pc = exct.start_pc(i);
1185 int end_pc = exct.end_pc(i);
1186 int handler_pc = exct.handler_pc(i);
1187 int catch_type = exct.catch_type_index(i);
1188
1189 if (start_pc <= bci && bci < end_pc) {
1190 BasicBlock *excBB = get_basic_block_at(handler_pc);
1191 CellTypeState *excStk = excBB->stack();
1192 CellTypeState *cOpStck = stack();
1193 CellTypeState cOpStck_0 = cOpStck[0];
1194 int cOpStackTop = _stack_top;
1195
1196 // Exception stacks are always the same.
1197 assert(method()->max_stack() > 0, "sanity check");
1198
1199 // We remembered the size and first element of "cOpStck"
1200 // above; now we temporarily set them to the appropriate
1201 // values for an exception handler. */
1202 cOpStck[0] = CellTypeState::make_slot_ref(_max_locals);
1203 _stack_top = 1;
1204
1205 merge_state_into_bb(excBB);
1206
1207 // Now undo the temporary change.
1208 cOpStck[0] = cOpStck_0;
1209 _stack_top = cOpStackTop;
1210
1211 // If this is a "catch all" handler, then we do not need to
1212 // consider any additional handlers.
1213 if (catch_type == 0) {
1214 return;
1215 }
1216 }
1217 }
1218 }
1219
1220 // It is possible that none of the exception handlers would have caught
1221 // the exception. In this case, we will exit the method. We must
1222 // ensure that the monitor stack is empty in this case.
1223 if (_monitor_top == 0) {
1224 return;
1225 }
1226
1227 // We pessimistically assume that this exception can escape the
1228 // method. (It is possible that it will always be caught, but
1229 // we don't care to analyse the types of the catch clauses.)
1230
1231 // We don't set _monitor_top to bad_monitors because there are no successors
1232 // to this exceptional exit.
1233
1234 if (TraceMonitorMismatch && _monitor_safe) {
1235 // We check _monitor_safe so that we only report the first mismatched
1236 // exceptional exit.
1237 report_monitor_mismatch("non-empty monitor stack at exceptional exit");
1238 }
1239 _monitor_safe = false;
1240
1241 }
1242
1243 void GenerateOopMap::report_monitor_mismatch(const char *msg) {
1244 #ifndef PRODUCT
1245 tty->print(" Monitor mismatch in method ");
1246 method()->print_short_name(tty);
1247 tty->print_cr(": %s", msg);
1248 #endif
1249 }
1250
1251 void GenerateOopMap::print_states(outputStream *os,
1252 CellTypeState* vec, int num) {
1253 for (int i = 0; i < num; i++) {
1254 vec[i].print(tty);
1255 }
1256 }
1257
1258 // Print the state values at the current bytecode.
1259 void GenerateOopMap::print_current_state(outputStream *os,
1260 BytecodeStream *currentBC,
1261 bool detailed) {
1262
1263 if (detailed) {
1264 os->print(" %4d vars = ", currentBC->bci());
1265 print_states(os, vars(), _max_locals);
1266 os->print(" %s", Bytecodes::name(currentBC->code()));
1267 switch(currentBC->code()) {
1268 case Bytecodes::_invokevirtual:
1269 case Bytecodes::_invokespecial:
1270 case Bytecodes::_invokestatic:
1271 case Bytecodes::_invokedynamic:
1272 case Bytecodes::_invokeinterface:
1273 int idx = currentBC->has_index_u4() ? currentBC->get_index_u4() : currentBC->get_index_u2_cpcache();
1274 constantPoolOop cp = method()->constants();
1275 int nameAndTypeIdx = cp->name_and_type_ref_index_at(idx);
1276 int signatureIdx = cp->signature_ref_index_at(nameAndTypeIdx);
1277 Symbol* signature = cp->symbol_at(signatureIdx);
1278 os->print("%s", signature->as_C_string());
1279 }
1280 os->cr();
1281 os->print(" stack = ");
1282 print_states(os, stack(), _stack_top);
1283 os->cr();
1284 if (_monitor_top != bad_monitors) {
1285 os->print(" monitors = ");
1286 print_states(os, monitors(), _monitor_top);
1287 } else {
1288 os->print(" [bad monitor stack]");
1289 }
1290 os->cr();
1291 } else {
1292 os->print(" %4d vars = '%s' ", currentBC->bci(), state_vec_to_string(vars(), _max_locals));
1293 os->print(" stack = '%s' ", state_vec_to_string(stack(), _stack_top));
1294 if (_monitor_top != bad_monitors) {
1295 os->print(" monitors = '%s' \t%s", state_vec_to_string(monitors(), _monitor_top), Bytecodes::name(currentBC->code()));
1296 } else {
1297 os->print(" [bad monitor stack]");
1298 }
1299 switch(currentBC->code()) {
1300 case Bytecodes::_invokevirtual:
1301 case Bytecodes::_invokespecial:
1302 case Bytecodes::_invokestatic:
1303 case Bytecodes::_invokedynamic:
1304 case Bytecodes::_invokeinterface:
1305 int idx = currentBC->has_index_u4() ? currentBC->get_index_u4() : currentBC->get_index_u2_cpcache();
1306 constantPoolOop cp = method()->constants();
1307 int nameAndTypeIdx = cp->name_and_type_ref_index_at(idx);
1308 int signatureIdx = cp->signature_ref_index_at(nameAndTypeIdx);
1309 Symbol* signature = cp->symbol_at(signatureIdx);
1310 os->print("%s", signature->as_C_string());
1311 }
1312 os->cr();
1313 }
1314 }
1315
1316 // Sets the current state to be the state after executing the
1317 // current instruction, starting in the current state.
1318 void GenerateOopMap::interp1(BytecodeStream *itr) {
1319 if (TraceNewOopMapGeneration) {
1320 print_current_state(tty, itr, TraceNewOopMapGenerationDetailed);
1321 }
1322
1323 // Should we report the results? Result is reported *before* the instruction at the current bci is executed.
1324 // However, not for calls. For calls we do not want to include the arguments, so we postpone the reporting until
1325 // they have been popped (in method ppl).
1326 if (_report_result == true) {
1327 switch(itr->code()) {
1328 case Bytecodes::_invokevirtual:
1329 case Bytecodes::_invokespecial:
1330 case Bytecodes::_invokestatic:
1331 case Bytecodes::_invokedynamic:
1332 case Bytecodes::_invokeinterface:
1333 _itr_send = itr;
1334 _report_result_for_send = true;
1335 break;
1336 default:
1337 fill_stackmap_for_opcodes(itr, vars(), stack(), _stack_top);
1338 break;
1339 }
1340 }
1341
1342 // abstract interpretation of current opcode
1343 switch(itr->code()) {
1344 case Bytecodes::_nop: break;
1345 case Bytecodes::_goto: break;
1346 case Bytecodes::_goto_w: break;
1347 case Bytecodes::_iinc: break;
1348 case Bytecodes::_return: do_return_monitor_check();
1349 break;
1350
1351 case Bytecodes::_aconst_null:
1352 case Bytecodes::_new: ppush1(CellTypeState::make_line_ref(itr->bci()));
1353 break;
1354
1355 case Bytecodes::_iconst_m1:
1356 case Bytecodes::_iconst_0:
1357 case Bytecodes::_iconst_1:
1358 case Bytecodes::_iconst_2:
1359 case Bytecodes::_iconst_3:
1360 case Bytecodes::_iconst_4:
1361 case Bytecodes::_iconst_5:
1362 case Bytecodes::_fconst_0:
1363 case Bytecodes::_fconst_1:
1364 case Bytecodes::_fconst_2:
1365 case Bytecodes::_bipush:
1366 case Bytecodes::_sipush: ppush1(valCTS); break;
1367
1368 case Bytecodes::_lconst_0:
1369 case Bytecodes::_lconst_1:
1370 case Bytecodes::_dconst_0:
1371 case Bytecodes::_dconst_1: ppush(vvCTS); break;
1372
1373 case Bytecodes::_ldc2_w: ppush(vvCTS); break;
1374
1375 case Bytecodes::_ldc: // fall through:
1376 case Bytecodes::_ldc_w: do_ldc(itr->bci()); break;
1377
1378 case Bytecodes::_iload:
1379 case Bytecodes::_fload: ppload(vCTS, itr->get_index()); break;
1380
1381 case Bytecodes::_lload:
1382 case Bytecodes::_dload: ppload(vvCTS,itr->get_index()); break;
1383
1384 case Bytecodes::_aload: ppload(rCTS, itr->get_index()); break;
1385
1386 case Bytecodes::_iload_0:
1387 case Bytecodes::_fload_0: ppload(vCTS, 0); break;
1388 case Bytecodes::_iload_1:
1389 case Bytecodes::_fload_1: ppload(vCTS, 1); break;
1390 case Bytecodes::_iload_2:
1391 case Bytecodes::_fload_2: ppload(vCTS, 2); break;
1392 case Bytecodes::_iload_3:
1393 case Bytecodes::_fload_3: ppload(vCTS, 3); break;
1394
1395 case Bytecodes::_lload_0:
1396 case Bytecodes::_dload_0: ppload(vvCTS, 0); break;
1397 case Bytecodes::_lload_1:
1398 case Bytecodes::_dload_1: ppload(vvCTS, 1); break;
1399 case Bytecodes::_lload_2:
1400 case Bytecodes::_dload_2: ppload(vvCTS, 2); break;
1401 case Bytecodes::_lload_3:
1402 case Bytecodes::_dload_3: ppload(vvCTS, 3); break;
1403
1404 case Bytecodes::_aload_0: ppload(rCTS, 0); break;
1405 case Bytecodes::_aload_1: ppload(rCTS, 1); break;
1406 case Bytecodes::_aload_2: ppload(rCTS, 2); break;
1407 case Bytecodes::_aload_3: ppload(rCTS, 3); break;
1408
1409 case Bytecodes::_iaload:
1410 case Bytecodes::_faload:
1411 case Bytecodes::_baload:
1412 case Bytecodes::_caload:
1413 case Bytecodes::_saload: pp(vrCTS, vCTS); break;
1414
1415 case Bytecodes::_laload: pp(vrCTS, vvCTS); break;
1416 case Bytecodes::_daload: pp(vrCTS, vvCTS); break;
1417
1418 case Bytecodes::_aaload: pp_new_ref(vrCTS, itr->bci()); break;
1419
1420 case Bytecodes::_istore:
1421 case Bytecodes::_fstore: ppstore(vCTS, itr->get_index()); break;
1422
1423 case Bytecodes::_lstore:
1424 case Bytecodes::_dstore: ppstore(vvCTS, itr->get_index()); break;
1425
1426 case Bytecodes::_astore: do_astore(itr->get_index()); break;
1427
1428 case Bytecodes::_istore_0:
1429 case Bytecodes::_fstore_0: ppstore(vCTS, 0); break;
1430 case Bytecodes::_istore_1:
1431 case Bytecodes::_fstore_1: ppstore(vCTS, 1); break;
1432 case Bytecodes::_istore_2:
1433 case Bytecodes::_fstore_2: ppstore(vCTS, 2); break;
1434 case Bytecodes::_istore_3:
1435 case Bytecodes::_fstore_3: ppstore(vCTS, 3); break;
1436
1437 case Bytecodes::_lstore_0:
1438 case Bytecodes::_dstore_0: ppstore(vvCTS, 0); break;
1439 case Bytecodes::_lstore_1:
1440 case Bytecodes::_dstore_1: ppstore(vvCTS, 1); break;
1441 case Bytecodes::_lstore_2:
1442 case Bytecodes::_dstore_2: ppstore(vvCTS, 2); break;
1443 case Bytecodes::_lstore_3:
1444 case Bytecodes::_dstore_3: ppstore(vvCTS, 3); break;
1445
1446 case Bytecodes::_astore_0: do_astore(0); break;
1447 case Bytecodes::_astore_1: do_astore(1); break;
1448 case Bytecodes::_astore_2: do_astore(2); break;
1449 case Bytecodes::_astore_3: do_astore(3); break;
1450
1451 case Bytecodes::_iastore:
1452 case Bytecodes::_fastore:
1453 case Bytecodes::_bastore:
1454 case Bytecodes::_castore:
1455 case Bytecodes::_sastore: ppop(vvrCTS); break;
1456 case Bytecodes::_lastore:
1457 case Bytecodes::_dastore: ppop(vvvrCTS); break;
1458 case Bytecodes::_aastore: ppop(rvrCTS); break;
1459
1460 case Bytecodes::_pop: ppop_any(1); break;
1461 case Bytecodes::_pop2: ppop_any(2); break;
1462
1463 case Bytecodes::_dup: ppdupswap(1, "11"); break;
1464 case Bytecodes::_dup_x1: ppdupswap(2, "121"); break;
1465 case Bytecodes::_dup_x2: ppdupswap(3, "1321"); break;
1466 case Bytecodes::_dup2: ppdupswap(2, "2121"); break;
1467 case Bytecodes::_dup2_x1: ppdupswap(3, "21321"); break;
1468 case Bytecodes::_dup2_x2: ppdupswap(4, "214321"); break;
1469 case Bytecodes::_swap: ppdupswap(2, "12"); break;
1470
1471 case Bytecodes::_iadd:
1472 case Bytecodes::_fadd:
1473 case Bytecodes::_isub:
1474 case Bytecodes::_fsub:
1475 case Bytecodes::_imul:
1476 case Bytecodes::_fmul:
1477 case Bytecodes::_idiv:
1478 case Bytecodes::_fdiv:
1479 case Bytecodes::_irem:
1480 case Bytecodes::_frem:
1481 case Bytecodes::_ishl:
1482 case Bytecodes::_ishr:
1483 case Bytecodes::_iushr:
1484 case Bytecodes::_iand:
1485 case Bytecodes::_ior:
1486 case Bytecodes::_ixor:
1487 case Bytecodes::_l2f:
1488 case Bytecodes::_l2i:
1489 case Bytecodes::_d2f:
1490 case Bytecodes::_d2i:
1491 case Bytecodes::_fcmpl:
1492 case Bytecodes::_fcmpg: pp(vvCTS, vCTS); break;
1493
1494 case Bytecodes::_ladd:
1495 case Bytecodes::_dadd:
1496 case Bytecodes::_lsub:
1497 case Bytecodes::_dsub:
1498 case Bytecodes::_lmul:
1499 case Bytecodes::_dmul:
1500 case Bytecodes::_ldiv:
1501 case Bytecodes::_ddiv:
1502 case Bytecodes::_lrem:
1503 case Bytecodes::_drem:
1504 case Bytecodes::_land:
1505 case Bytecodes::_lor:
1506 case Bytecodes::_lxor: pp(vvvvCTS, vvCTS); break;
1507
1508 case Bytecodes::_ineg:
1509 case Bytecodes::_fneg:
1510 case Bytecodes::_i2f:
1511 case Bytecodes::_f2i:
1512 case Bytecodes::_i2c:
1513 case Bytecodes::_i2s:
1514 case Bytecodes::_i2b: pp(vCTS, vCTS); break;
1515
1516 case Bytecodes::_lneg:
1517 case Bytecodes::_dneg:
1518 case Bytecodes::_l2d:
1519 case Bytecodes::_d2l: pp(vvCTS, vvCTS); break;
1520
1521 case Bytecodes::_lshl:
1522 case Bytecodes::_lshr:
1523 case Bytecodes::_lushr: pp(vvvCTS, vvCTS); break;
1524
1525 case Bytecodes::_i2l:
1526 case Bytecodes::_i2d:
1527 case Bytecodes::_f2l:
1528 case Bytecodes::_f2d: pp(vCTS, vvCTS); break;
1529
1530 case Bytecodes::_lcmp: pp(vvvvCTS, vCTS); break;
1531 case Bytecodes::_dcmpl:
1532 case Bytecodes::_dcmpg: pp(vvvvCTS, vCTS); break;
1533
1534 case Bytecodes::_ifeq:
1535 case Bytecodes::_ifne:
1536 case Bytecodes::_iflt:
1537 case Bytecodes::_ifge:
1538 case Bytecodes::_ifgt:
1539 case Bytecodes::_ifle:
1540 case Bytecodes::_tableswitch: ppop1(valCTS);
1541 break;
1542 case Bytecodes::_ireturn:
1543 case Bytecodes::_freturn: do_return_monitor_check();
1544 ppop1(valCTS);
1545 break;
1546 case Bytecodes::_if_icmpeq:
1547 case Bytecodes::_if_icmpne:
1548 case Bytecodes::_if_icmplt:
1549 case Bytecodes::_if_icmpge:
1550 case Bytecodes::_if_icmpgt:
1551 case Bytecodes::_if_icmple: ppop(vvCTS);
1552 break;
1553
1554 case Bytecodes::_lreturn: do_return_monitor_check();
1555 ppop(vvCTS);
1556 break;
1557
1558 case Bytecodes::_dreturn: do_return_monitor_check();
1559 ppop(vvCTS);
1560 break;
1561
1562 case Bytecodes::_if_acmpeq:
1563 case Bytecodes::_if_acmpne: ppop(rrCTS); break;
1564
1565 case Bytecodes::_jsr: do_jsr(itr->dest()); break;
1566 case Bytecodes::_jsr_w: do_jsr(itr->dest_w()); break;
1567
1568 case Bytecodes::_getstatic: do_field(true, true, itr->get_index_u2_cpcache(), itr->bci()); break;
1569 case Bytecodes::_putstatic: do_field(false, true, itr->get_index_u2_cpcache(), itr->bci()); break;
1570 case Bytecodes::_getfield: do_field(true, false, itr->get_index_u2_cpcache(), itr->bci()); break;
1571 case Bytecodes::_putfield: do_field(false, false, itr->get_index_u2_cpcache(), itr->bci()); break;
1572
1573 case Bytecodes::_invokevirtual:
1574 case Bytecodes::_invokespecial: do_method(false, false, itr->get_index_u2_cpcache(), itr->bci()); break;
1575 case Bytecodes::_invokestatic: do_method(true, false, itr->get_index_u2_cpcache(), itr->bci()); break;
1576 case Bytecodes::_invokedynamic: do_method(true, false, itr->get_index_u4(), itr->bci()); break;
1577 case Bytecodes::_invokeinterface: do_method(false, true, itr->get_index_u2_cpcache(), itr->bci()); break;
1578 case Bytecodes::_newarray:
1579 case Bytecodes::_anewarray: pp_new_ref(vCTS, itr->bci()); break;
1580 case Bytecodes::_checkcast: do_checkcast(); break;
1581 case Bytecodes::_arraylength:
1582 case Bytecodes::_instanceof: pp(rCTS, vCTS); break;
1583 case Bytecodes::_monitorenter: do_monitorenter(itr->bci()); break;
1584 case Bytecodes::_monitorexit: do_monitorexit(itr->bci()); break;
1585
1586 case Bytecodes::_athrow: // handled by do_exception_edge() BUT ...
1587 // vlh(apple): do_exception_edge() does not get
1588 // called if method has no exception handlers
1589 if ((!_has_exceptions) && (_monitor_top > 0)) {
1590 _monitor_safe = false;
1591 }
1592 break;
1593
1594 case Bytecodes::_areturn: do_return_monitor_check();
1595 ppop1(refCTS);
1596 break;
1597 case Bytecodes::_ifnull:
1598 case Bytecodes::_ifnonnull: ppop1(refCTS); break;
1599 case Bytecodes::_multianewarray: do_multianewarray(*(itr->bcp()+3), itr->bci()); break;
1600
1601 case Bytecodes::_wide: fatal("Iterator should skip this bytecode"); break;
1602 case Bytecodes::_ret: break;
1603
1604 // Java opcodes
1605 case Bytecodes::_lookupswitch: ppop1(valCTS); break;
1606
1607 default:
1608 tty->print("unexpected opcode: %d\n", itr->code());
1609 ShouldNotReachHere();
1610 break;
1611 }
1612 }
1613
1614 void GenerateOopMap::check_type(CellTypeState expected, CellTypeState actual) {
1615 if (!expected.equal_kind(actual)) {
1616 verify_error("wrong type on stack (found: %c expected: %c)", actual.to_char(), expected.to_char());
1617 }
1618 }
1619
1620 void GenerateOopMap::ppstore(CellTypeState *in, int loc_no) {
1621 while(!(*in).is_bottom()) {
1622 CellTypeState expected =*in++;
1623 CellTypeState actual = pop();
1624 check_type(expected, actual);
1625 assert(loc_no >= 0, "sanity check");
1626 set_var(loc_no++, actual);
1627 }
1628 }
1629
1630 void GenerateOopMap::ppload(CellTypeState *out, int loc_no) {
1631 while(!(*out).is_bottom()) {
1632 CellTypeState out1 = *out++;
1633 CellTypeState vcts = get_var(loc_no);
1634 assert(out1.can_be_reference() || out1.can_be_value(),
1635 "can only load refs. and values.");
1636 if (out1.is_reference()) {
1637 assert(loc_no>=0, "sanity check");
1638 if (!vcts.is_reference()) {
1639 // We were asked to push a reference, but the type of the
1640 // variable can be something else
1641 _conflict = true;
1642 if (vcts.can_be_uninit()) {
1643 // It is a ref-uninit conflict (at least). If there are other
1644 // problems, we'll get them in the next round
1645 add_to_ref_init_set(loc_no);
1646 vcts = out1;
1647 } else {
1648 // It wasn't a ref-uninit conflict. So must be a
1649 // ref-val or ref-pc conflict. Split the variable.
1650 record_refval_conflict(loc_no);
1651 vcts = out1;
1652 }
1653 push(out1); // recover...
1654 } else {
1655 push(vcts); // preserve reference.
1656 }
1657 // Otherwise it is a conflict, but one that verification would
1658 // have caught if illegal. In particular, it can't be a topCTS
1659 // resulting from mergeing two difference pcCTS's since the verifier
1660 // would have rejected any use of such a merge.
1661 } else {
1662 push(out1); // handle val/init conflict
1663 }
1664 loc_no++;
1665 }
1666 }
1667
1668 void GenerateOopMap::ppdupswap(int poplen, const char *out) {
1669 CellTypeState actual[5];
1670 assert(poplen < 5, "this must be less than length of actual vector");
1671
1672 // pop all arguments
1673 for(int i = 0; i < poplen; i++) actual[i] = pop();
1674
1675 // put them back
1676 char push_ch = *out++;
1677 while (push_ch != '\0') {
1678 int idx = push_ch - '1';
1679 assert(idx >= 0 && idx < poplen, "wrong arguments");
1680 push(actual[idx]);
1681 push_ch = *out++;
1682 }
1683 }
1684
1685 void GenerateOopMap::ppop1(CellTypeState out) {
1686 CellTypeState actual = pop();
1687 check_type(out, actual);
1688 }
1689
1690 void GenerateOopMap::ppop(CellTypeState *out) {
1691 while (!(*out).is_bottom()) {
1692 ppop1(*out++);
1693 }
1694 }
1695
1696 void GenerateOopMap::ppush1(CellTypeState in) {
1697 assert(in.is_reference() | in.is_value(), "sanity check");
1698 push(in);
1699 }
1700
1701 void GenerateOopMap::ppush(CellTypeState *in) {
1702 while (!(*in).is_bottom()) {
1703 ppush1(*in++);
1704 }
1705 }
1706
1707 void GenerateOopMap::pp(CellTypeState *in, CellTypeState *out) {
1708 ppop(in);
1709 ppush(out);
1710 }
1711
1712 void GenerateOopMap::pp_new_ref(CellTypeState *in, int bci) {
1713 ppop(in);
1714 ppush1(CellTypeState::make_line_ref(bci));
1715 }
1716
1717 void GenerateOopMap::ppop_any(int poplen) {
1718 if (_stack_top >= poplen) {
1719 _stack_top -= poplen;
1720 } else {
1721 verify_error("stack underflow");
1722 }
1723 }
1724
1725 // Replace all occurences of the state 'match' with the state 'replace'
1726 // in our current state vector.
1727 void GenerateOopMap::replace_all_CTS_matches(CellTypeState match,
1728 CellTypeState replace) {
1729 int i;
1730 int len = _max_locals + _stack_top;
1731 bool change = false;
1732
1733 for (i = len - 1; i >= 0; i--) {
1734 if (match.equal(_state[i])) {
1735 _state[i] = replace;
1736 }
1737 }
1738
1739 if (_monitor_top > 0) {
1740 int base = _max_locals + _max_stack;
1741 len = base + _monitor_top;
1742 for (i = len - 1; i >= base; i--) {
1743 if (match.equal(_state[i])) {
1744 _state[i] = replace;
1745 }
1746 }
1747 }
1748 }
1749
1750 void GenerateOopMap::do_checkcast() {
1751 CellTypeState actual = pop();
1752 check_type(refCTS, actual);
1753 push(actual);
1754 }
1755
1756 void GenerateOopMap::do_monitorenter(int bci) {
1757 CellTypeState actual = pop();
1758 if (_monitor_top == bad_monitors) {
1759 return;
1760 }
1761
1762 // Bail out when we get repeated locks on an identical monitor. This case
1763 // isn't too hard to handle and can be made to work if supporting nested
1764 // redundant synchronized statements becomes a priority.
1765 //
1766 // See also "Note" in do_monitorexit(), below.
1767 if (actual.is_lock_reference()) {
1768 _monitor_top = bad_monitors;
1769 _monitor_safe = false;
1770
1771 if (TraceMonitorMismatch) {
1772 report_monitor_mismatch("nested redundant lock -- bailout...");
1773 }
1774 return;
1775 }
1776
1777 CellTypeState lock = CellTypeState::make_lock_ref(bci);
1778 check_type(refCTS, actual);
1779 if (!actual.is_info_top()) {
1780 replace_all_CTS_matches(actual, lock);
1781 monitor_push(lock);
1782 }
1783 }
1784
1785 void GenerateOopMap::do_monitorexit(int bci) {
1786 CellTypeState actual = pop();
1787 if (_monitor_top == bad_monitors) {
1788 return;
1789 }
1790 check_type(refCTS, actual);
1791 CellTypeState expected = monitor_pop();
1792 if (!actual.is_lock_reference() || !expected.equal(actual)) {
1793 // The monitor we are exiting is not verifiably the one
1794 // on the top of our monitor stack. This causes a monitor
1795 // mismatch.
1796 _monitor_top = bad_monitors;
1797 _monitor_safe = false;
1798
1799 // We need to mark this basic block as changed so that
1800 // this monitorexit will be visited again. We need to
1801 // do this to ensure that we have accounted for the
1802 // possibility that this bytecode will throw an
1803 // exception.
1804 BasicBlock* bb = get_basic_block_containing(bci);
1805 bb->set_changed(true);
1806 bb->_monitor_top = bad_monitors;
1807
1808 if (TraceMonitorMismatch) {
1809 report_monitor_mismatch("improper monitor pair");
1810 }
1811 } else {
1812 // This code is a fix for the case where we have repeated
1813 // locking of the same object in straightline code. We clear
1814 // out the lock when it is popped from the monitor stack
1815 // and replace it with an unobtrusive reference value that can
1816 // be locked again.
1817 //
1818 // Note: when generateOopMap is fixed to properly handle repeated,
1819 // nested, redundant locks on the same object, then this
1820 // fix will need to be removed at that time.
1821 replace_all_CTS_matches(actual, CellTypeState::make_line_ref(bci));
1822 }
1823 }
1824
1825 void GenerateOopMap::do_return_monitor_check() {
1826 if (_monitor_top > 0) {
1827 // The monitor stack must be empty when we leave the method
1828 // for the monitors to be properly matched.
1829 _monitor_safe = false;
1830
1831 // Since there are no successors to the *return bytecode, it
1832 // isn't necessary to set _monitor_top to bad_monitors.
1833
1834 if (TraceMonitorMismatch) {
1835 report_monitor_mismatch("non-empty monitor stack at return");
1836 }
1837 }
1838 }
1839
1840 void GenerateOopMap::do_jsr(int targ_bci) {
1841 push(CellTypeState::make_addr(targ_bci));
1842 }
1843
1844
1845
1846 void GenerateOopMap::do_ldc(int bci) {
1847 Bytecode_loadconstant ldc(method(), bci);
1848 constantPoolOop cp = method()->constants();
1849 BasicType bt = ldc.result_type();
1850 CellTypeState cts = (bt == T_OBJECT) ? CellTypeState::make_line_ref(bci) : valCTS;
1851 // Make sure bt==T_OBJECT is the same as old code (is_pointer_entry).
1852 // Note that CONSTANT_MethodHandle entries are u2 index pairs, not pointer-entries,
1853 // and they are processed by _fast_aldc and the CP cache.
1854 assert((ldc.has_cache_index() || cp->is_object_entry(ldc.pool_index()))
1855 ? (bt == T_OBJECT) : true, "expected object type");
1856 ppush1(cts);
1857 }
1858
1859 void GenerateOopMap::do_multianewarray(int dims, int bci) {
1860 assert(dims >= 1, "sanity check");
1861 for(int i = dims -1; i >=0; i--) {
1862 ppop1(valCTS);
1863 }
1864 ppush1(CellTypeState::make_line_ref(bci));
1865 }
1866
1867 void GenerateOopMap::do_astore(int idx) {
1868 CellTypeState r_or_p = pop();
1869 if (!r_or_p.is_address() && !r_or_p.is_reference()) {
1870 // We actually expected ref or pc, but we only report that we expected a ref. It does not
1871 // really matter (at least for now)
1872 verify_error("wrong type on stack (found: %c, expected: {pr})", r_or_p.to_char());
1873 return;
1874 }
1875 set_var(idx, r_or_p);
1876 }
1877
1878 // Copies bottom/zero terminated CTS string from "src" into "dst".
1879 // Does NOT terminate with a bottom. Returns the number of cells copied.
1880 int GenerateOopMap::copy_cts(CellTypeState *dst, CellTypeState *src) {
1881 int idx = 0;
1882 while (!src[idx].is_bottom()) {
1883 dst[idx] = src[idx];
1884 idx++;
1885 }
1886 return idx;
1887 }
1888
1889 void GenerateOopMap::do_field(int is_get, int is_static, int idx, int bci) {
1890 // Dig up signature for field in constant pool
1891 constantPoolOop cp = method()->constants();
1892 int nameAndTypeIdx = cp->name_and_type_ref_index_at(idx);
1893 int signatureIdx = cp->signature_ref_index_at(nameAndTypeIdx);
1894 Symbol* signature = cp->symbol_at(signatureIdx);
1895
1896 // Parse signature (espcially simple for fields)
1897 assert(signature->utf8_length() > 0, "field signatures cannot have zero length");
1898 // The signature is UFT8 encoded, but the first char is always ASCII for signatures.
1899 char sigch = (char)*(signature->base());
1900 CellTypeState temp[4];
1901 CellTypeState *eff = sigchar_to_effect(sigch, bci, temp);
1902
1903 CellTypeState in[4];
1904 CellTypeState *out;
1905 int i = 0;
1906
1907 if (is_get) {
1908 out = eff;
1909 } else {
1910 out = epsilonCTS;
1911 i = copy_cts(in, eff);
1912 }
1913 if (!is_static) in[i++] = CellTypeState::ref;
1914 in[i] = CellTypeState::bottom;
1915 assert(i<=3, "sanity check");
1916 pp(in, out);
1917 }
1918
1919 void GenerateOopMap::do_method(int is_static, int is_interface, int idx, int bci) {
1920 // Dig up signature for field in constant pool
1921 constantPoolOop cp = _method->constants();
1922 Symbol* signature = cp->signature_ref_at(idx);
1923
1924 // Parse method signature
1925 CellTypeState out[4];
1926 CellTypeState in[MAXARGSIZE+1]; // Includes result
1927 ComputeCallStack cse(signature);
1928
1929 // Compute return type
1930 int res_length= cse.compute_for_returntype(out);
1931
1932 // Temporary hack.
1933 if (out[0].equal(CellTypeState::ref) && out[1].equal(CellTypeState::bottom)) {
1934 out[0] = CellTypeState::make_line_ref(bci);
1935 }
1936
1937 assert(res_length<=4, "max value should be vv");
1938
1939 // Compute arguments
1940 int arg_length = cse.compute_for_parameters(is_static != 0, in);
1941 assert(arg_length<=MAXARGSIZE, "too many locals");
1942
1943 // Pop arguments
1944 for (int i = arg_length - 1; i >= 0; i--) ppop1(in[i]);// Do args in reverse order.
1945
1946 // Report results
1947 if (_report_result_for_send == true) {
1948 fill_stackmap_for_opcodes(_itr_send, vars(), stack(), _stack_top);
1949 _report_result_for_send = false;
1950 }
1951
1952 // Push return address
1953 ppush(out);
1954 }
1955
1956 // This is used to parse the signature for fields, since they are very simple...
1957 CellTypeState *GenerateOopMap::sigchar_to_effect(char sigch, int bci, CellTypeState *out) {
1958 // Object and array
1959 if (sigch=='L' || sigch=='[') {
1960 out[0] = CellTypeState::make_line_ref(bci);
1961 out[1] = CellTypeState::bottom;
1962 return out;
1963 }
1964 if (sigch == 'J' || sigch == 'D' ) return vvCTS; // Long and Double
1965 if (sigch == 'V' ) return epsilonCTS; // Void
1966 return vCTS; // Otherwise
1967 }
1968
1969 long GenerateOopMap::_total_byte_count = 0;
1970 elapsedTimer GenerateOopMap::_total_oopmap_time;
1971
1972 // This function assumes "bcs" is at a "ret" instruction and that the vars
1973 // state is valid for that instruction. Furthermore, the ret instruction
1974 // must be the last instruction in "bb" (we store information about the
1975 // "ret" in "bb").
1976 void GenerateOopMap::ret_jump_targets_do(BytecodeStream *bcs, jmpFct_t jmpFct, int varNo, int *data) {
1977 CellTypeState ra = vars()[varNo];
1978 if (!ra.is_good_address()) {
1979 verify_error("ret returns from two jsr subroutines?");
1980 return;
1981 }
1982 int target = ra.get_info();
1983
1984 RetTableEntry* rtEnt = _rt.find_jsrs_for_target(target);
1985 int bci = bcs->bci();
1986 for (int i = 0; i < rtEnt->nof_jsrs(); i++) {
1987 int target_bci = rtEnt->jsrs(i);
1988 // Make sure a jrtRet does not set the changed bit for dead basicblock.
1989 BasicBlock* jsr_bb = get_basic_block_containing(target_bci - 1);
1990 debug_only(BasicBlock* target_bb = &jsr_bb[1];)
1991 assert(target_bb == get_basic_block_at(target_bci), "wrong calc. of successor basicblock");
1992 bool alive = jsr_bb->is_alive();
1993 if (TraceNewOopMapGeneration) {
1994 tty->print("pc = %d, ret -> %d alive: %s\n", bci, target_bci, alive ? "true" : "false");
1995 }
1996 if (alive) jmpFct(this, target_bci, data);
1997 }
1998 }
1999
2000 //
2001 // Debug method
2002 //
2003 char* GenerateOopMap::state_vec_to_string(CellTypeState* vec, int len) {
2004 #ifdef ASSERT
2005 int checklen = MAX3(_max_locals, _max_stack, _max_monitors) + 1;
2006 assert(len < checklen, "state_vec_buf overflow");
2007 #endif
2008 for (int i = 0; i < len; i++) _state_vec_buf[i] = vec[i].to_char();
2009 _state_vec_buf[len] = 0;
2010 return _state_vec_buf;
2011 }
2012
2013 void GenerateOopMap::print_time() {
2014 tty->print_cr ("Accumulated oopmap times:");
2015 tty->print_cr ("---------------------------");
2016 tty->print_cr (" Total : %3.3f sec.", GenerateOopMap::_total_oopmap_time.seconds());
2017 tty->print_cr (" (%3.0f bytecodes per sec) ",
2018 GenerateOopMap::_total_byte_count / GenerateOopMap::_total_oopmap_time.seconds());
2019 }
2020
2021 //
2022 // ============ Main Entry Point ===========
2023 //
2024 GenerateOopMap::GenerateOopMap(methodHandle method) {
2025 // We have to initialize all variables here, that can be queried directly
2026 _method = method;
2027 _max_locals=0;
2028 _init_vars = NULL;
2029
2030 #ifndef PRODUCT
2031 // If we are doing a detailed trace, include the regular trace information.
2032 if (TraceNewOopMapGenerationDetailed) {
2033 TraceNewOopMapGeneration = true;
2034 }
2035 #endif
2036 }
2037
2038 void GenerateOopMap::compute_map(TRAPS) {
2039 #ifndef PRODUCT
2040 if (TimeOopMap2) {
2041 method()->print_short_name(tty);
2042 tty->print(" ");
2043 }
2044 if (TimeOopMap) {
2045 _total_byte_count += method()->code_size();
2046 }
2047 #endif
2048 TraceTime t_single("oopmap time", TimeOopMap2);
2049 TraceTime t_all(NULL, &_total_oopmap_time, TimeOopMap);
2050
2051 // Initialize values
2052 _got_error = false;
2053 _conflict = false;
2054 _max_locals = method()->max_locals();
2055 _max_stack = method()->max_stack();
2056 _has_exceptions = (method()->has_exception_handler());
2057 _nof_refval_conflicts = 0;
2058 _init_vars = new GrowableArray<intptr_t>(5); // There are seldom more than 5 init_vars
2059 _report_result = false;
2060 _report_result_for_send = false;
2061 _new_var_map = NULL;
2062 _ret_adr_tos = new GrowableArray<intptr_t>(5); // 5 seems like a good number;
2063 _did_rewriting = false;
2064 _did_relocation = false;
2065
2066 if (TraceNewOopMapGeneration) {
2067 tty->print("Method name: %s\n", method()->name()->as_C_string());
2068 if (Verbose) {
2069 _method->print_codes();
2070 tty->print_cr("Exception table:");
2071 ExceptionTable excps(method());
2072 for(int i = 0; i < excps.length(); i ++) {
2073 tty->print_cr("[%d - %d] -> %d",
2074 excps.start_pc(i), excps.end_pc(i), excps.handler_pc(i));
2075 }
2076 }
2077 }
2078
2079 // if no code - do nothing
2080 // compiler needs info
2081 if (method()->code_size() == 0 || _max_locals + method()->max_stack() == 0) {
2082 fill_stackmap_prolog(0);
2083 fill_stackmap_epilog();
2084 return;
2085 }
2086 // Step 1: Compute all jump targets and their return value
2087 if (!_got_error)
2088 _rt.compute_ret_table(_method);
2089
2090 // Step 2: Find all basic blocks and count GC points
2091 if (!_got_error)
2092 mark_bbheaders_and_count_gc_points();
2093
2094 // Step 3: Calculate stack maps
2095 if (!_got_error)
2096 do_interpretation();
2097
2098 // Step 4:Return results
2099 if (!_got_error && report_results())
2100 report_result();
2101
2102 if (_got_error) {
2103 THROW_HANDLE(_exception);
2104 }
2105 }
2106
2107 // Error handling methods
2108 // These methods create an exception for the current thread which is thrown
2109 // at the bottom of the call stack, when it returns to compute_map(). The
2110 // _got_error flag controls execution. NOT TODO: The VM exception propagation
2111 // mechanism using TRAPS/CHECKs could be used here instead but it would need
2112 // to be added as a parameter to every function and checked for every call.
2113 // The tons of extra code it would generate didn't seem worth the change.
2114 //
2115 void GenerateOopMap::error_work(const char *format, va_list ap) {
2116 _got_error = true;
2117 char msg_buffer[512];
2118 vsnprintf(msg_buffer, sizeof(msg_buffer), format, ap);
2119 // Append method name
2120 char msg_buffer2[512];
2121 jio_snprintf(msg_buffer2, sizeof(msg_buffer2), "%s in method %s", msg_buffer, method()->name()->as_C_string());
2122 _exception = Exceptions::new_exception(Thread::current(),
2123 vmSymbols::java_lang_LinkageError(), msg_buffer2);
2124 }
2125
2126 void GenerateOopMap::report_error(const char *format, ...) {
2127 va_list ap;
2128 va_start(ap, format);
2129 error_work(format, ap);
2130 }
2131
2132 void GenerateOopMap::verify_error(const char *format, ...) {
2133 // We do not distinguish between different types of errors for verification
2134 // errors. Let the verifier give a better message.
2135 const char *msg = "Illegal class file encountered. Try running with -Xverify:all";
2136 _got_error = true;
2137 // Append method name
2138 char msg_buffer2[512];
2139 jio_snprintf(msg_buffer2, sizeof(msg_buffer2), "%s in method %s", msg,
2140 method()->name()->as_C_string());
2141 _exception = Exceptions::new_exception(Thread::current(),
2142 vmSymbols::java_lang_LinkageError(), msg_buffer2);
2143 }
2144
2145 //
2146 // Report result opcodes
2147 //
2148 void GenerateOopMap::report_result() {
2149
2150 if (TraceNewOopMapGeneration) tty->print_cr("Report result pass");
2151
2152 // We now want to report the result of the parse
2153 _report_result = true;
2154
2155 // Prolog code
2156 fill_stackmap_prolog(_gc_points);
2157
2158 // Mark everything changed, then do one interpretation pass.
2159 for (int i = 0; i<_bb_count; i++) {
2160 if (_basic_blocks[i].is_reachable()) {
2161 _basic_blocks[i].set_changed(true);
2162 interp_bb(&_basic_blocks[i]);
2163 }
2164 }
2165
2166 // Note: Since we are skipping dead-code when we are reporting results, then
2167 // the no. of encountered gc-points might be fewer than the previously number
2168 // we have counted. (dead-code is a pain - it should be removed before we get here)
2169 fill_stackmap_epilog();
2170
2171 // Report initvars
2172 fill_init_vars(_init_vars);
2173
2174 _report_result = false;
2175 }
2176
2177 void GenerateOopMap::result_for_basicblock(int bci) {
2178 if (TraceNewOopMapGeneration) tty->print_cr("Report result pass for basicblock");
2179
2180 // We now want to report the result of the parse
2181 _report_result = true;
2182
2183 // Find basicblock and report results
2184 BasicBlock* bb = get_basic_block_containing(bci);
2185 assert(bb->is_reachable(), "getting result from unreachable basicblock");
2186 bb->set_changed(true);
2187 interp_bb(bb);
2188 }
2189
2190 //
2191 // Conflict handling code
2192 //
2193
2194 void GenerateOopMap::record_refval_conflict(int varNo) {
2195 assert(varNo>=0 && varNo< _max_locals, "index out of range");
2196
2197 if (TraceOopMapRewrites) {
2198 tty->print("### Conflict detected (local no: %d)\n", varNo);
2199 }
2200
2201 if (!_new_var_map) {
2202 _new_var_map = NEW_RESOURCE_ARRAY(int, _max_locals);
2203 for (int k = 0; k < _max_locals; k++) _new_var_map[k] = k;
2204 }
2205
2206 if ( _new_var_map[varNo] == varNo) {
2207 // Check if max. number of locals has been reached
2208 if (_max_locals + _nof_refval_conflicts >= MAX_LOCAL_VARS) {
2209 report_error("Rewriting exceeded local variable limit");
2210 return;
2211 }
2212 _new_var_map[varNo] = _max_locals + _nof_refval_conflicts;
2213 _nof_refval_conflicts++;
2214 }
2215 }
2216
2217 void GenerateOopMap::rewrite_refval_conflicts()
2218 {
2219 // We can get here two ways: Either a rewrite conflict was detected, or
2220 // an uninitialize reference was detected. In the second case, we do not
2221 // do any rewriting, we just want to recompute the reference set with the
2222 // new information
2223
2224 int nof_conflicts = 0; // Used for debugging only
2225
2226 if ( _nof_refval_conflicts == 0 )
2227 return;
2228
2229 // Check if rewrites are allowed in this parse.
2230 if (!allow_rewrites() && !IgnoreRewrites) {
2231 fatal("Rewriting method not allowed at this stage");
2232 }
2233
2234
2235 // This following flag is to tempoary supress rewrites. The locals that might conflict will
2236 // all be set to contain values. This is UNSAFE - however, until the rewriting has been completely
2237 // tested it is nice to have.
2238 if (IgnoreRewrites) {
2239 if (Verbose) {
2240 tty->print("rewrites suppressed for local no. ");
2241 for (int l = 0; l < _max_locals; l++) {
2242 if (_new_var_map[l] != l) {
2243 tty->print("%d ", l);
2244 vars()[l] = CellTypeState::value;
2245 }
2246 }
2247 tty->cr();
2248 }
2249
2250 // That was that...
2251 _new_var_map = NULL;
2252 _nof_refval_conflicts = 0;
2253 _conflict = false;
2254
2255 return;
2256 }
2257
2258 // Tracing flag
2259 _did_rewriting = true;
2260
2261 if (TraceOopMapRewrites) {
2262 tty->print_cr("ref/value conflict for method %s - bytecodes are getting rewritten", method()->name()->as_C_string());
2263 method()->print();
2264 method()->print_codes();
2265 }
2266
2267 assert(_new_var_map!=NULL, "nothing to rewrite");
2268 assert(_conflict==true, "We should not be here");
2269
2270 compute_ret_adr_at_TOS();
2271 if (!_got_error) {
2272 for (int k = 0; k < _max_locals && !_got_error; k++) {
2273 if (_new_var_map[k] != k) {
2274 if (TraceOopMapRewrites) {
2275 tty->print_cr("Rewriting: %d -> %d", k, _new_var_map[k]);
2276 }
2277 rewrite_refval_conflict(k, _new_var_map[k]);
2278 if (_got_error) return;
2279 nof_conflicts++;
2280 }
2281 }
2282 }
2283
2284 assert(nof_conflicts == _nof_refval_conflicts, "sanity check");
2285
2286 // Adjust the number of locals
2287 method()->set_max_locals(_max_locals+_nof_refval_conflicts);
2288 _max_locals += _nof_refval_conflicts;
2289
2290 // That was that...
2291 _new_var_map = NULL;
2292 _nof_refval_conflicts = 0;
2293 }
2294
2295 void GenerateOopMap::rewrite_refval_conflict(int from, int to) {
2296 bool startOver;
2297 do {
2298 // Make sure that the BytecodeStream is constructed in the loop, since
2299 // during rewriting a new method oop is going to be used, and the next time
2300 // around we want to use that.
2301 BytecodeStream bcs(_method);
2302 startOver = false;
2303
2304 while( bcs.next() >=0 && !startOver && !_got_error) {
2305 startOver = rewrite_refval_conflict_inst(&bcs, from, to);
2306 }
2307 } while (startOver && !_got_error);
2308 }
2309
2310 /* If the current instruction is one that uses local variable "from"
2311 in a ref way, change it to use "to". There's a subtle reason why we
2312 renumber the ref uses and not the non-ref uses: non-ref uses may be
2313 2 slots wide (double, long) which would necessitate keeping track of
2314 whether we should add one or two variables to the method. If the change
2315 affected the width of some instruction, returns "TRUE"; otherwise, returns "FALSE".
2316 Another reason for moving ref's value is for solving (addr, ref) conflicts, which
2317 both uses aload/astore methods.
2318 */
2319 bool GenerateOopMap::rewrite_refval_conflict_inst(BytecodeStream *itr, int from, int to) {
2320 Bytecodes::Code bc = itr->code();
2321 int index;
2322 int bci = itr->bci();
2323
2324 if (is_aload(itr, &index) && index == from) {
2325 if (TraceOopMapRewrites) {
2326 tty->print_cr("Rewriting aload at bci: %d", bci);
2327 }
2328 return rewrite_load_or_store(itr, Bytecodes::_aload, Bytecodes::_aload_0, to);
2329 }
2330
2331 if (is_astore(itr, &index) && index == from) {
2332 if (!stack_top_holds_ret_addr(bci)) {
2333 if (TraceOopMapRewrites) {
2334 tty->print_cr("Rewriting astore at bci: %d", bci);
2335 }
2336 return rewrite_load_or_store(itr, Bytecodes::_astore, Bytecodes::_astore_0, to);
2337 } else {
2338 if (TraceOopMapRewrites) {
2339 tty->print_cr("Supress rewriting of astore at bci: %d", bci);
2340 }
2341 }
2342 }
2343
2344 return false;
2345 }
2346
2347 // The argument to this method is:
2348 // bc : Current bytecode
2349 // bcN : either _aload or _astore
2350 // bc0 : either _aload_0 or _astore_0
2351 bool GenerateOopMap::rewrite_load_or_store(BytecodeStream *bcs, Bytecodes::Code bcN, Bytecodes::Code bc0, unsigned int varNo) {
2352 assert(bcN == Bytecodes::_astore || bcN == Bytecodes::_aload, "wrong argument (bcN)");
2353 assert(bc0 == Bytecodes::_astore_0 || bc0 == Bytecodes::_aload_0, "wrong argument (bc0)");
2354 int ilen = Bytecodes::length_at(_method(), bcs->bcp());
2355 int newIlen;
2356
2357 if (ilen == 4) {
2358 // Original instruction was wide; keep it wide for simplicity
2359 newIlen = 4;
2360 } else if (varNo < 4)
2361 newIlen = 1;
2362 else if (varNo >= 256)
2363 newIlen = 4;
2364 else
2365 newIlen = 2;
2366
2367 // If we need to relocate in order to patch the byte, we
2368 // do the patching in a temp. buffer, that is passed to the reloc.
2369 // The patching of the bytecode stream is then done by the Relocator.
2370 // This is neccesary, since relocating the instruction at a certain bci, might
2371 // also relocate that instruction, e.g., if a _goto before it gets widen to a _goto_w.
2372 // Hence, we do not know which bci to patch after relocation.
2373
2374 assert(newIlen <= 4, "sanity check");
2375 u_char inst_buffer[4]; // Max. instruction size is 4.
2376 address bcp;
2377
2378 if (newIlen != ilen) {
2379 // Relocation needed do patching in temp. buffer
2380 bcp = (address)inst_buffer;
2381 } else {
2382 bcp = _method->bcp_from(bcs->bci());
2383 }
2384
2385 // Patch either directly in methodOop or in temp. buffer
2386 if (newIlen == 1) {
2387 assert(varNo < 4, "varNo too large");
2388 *bcp = bc0 + varNo;
2389 } else if (newIlen == 2) {
2390 assert(varNo < 256, "2-byte index needed!");
2391 *(bcp + 0) = bcN;
2392 *(bcp + 1) = varNo;
2393 } else {
2394 assert(newIlen == 4, "Wrong instruction length");
2395 *(bcp + 0) = Bytecodes::_wide;
2396 *(bcp + 1) = bcN;
2397 Bytes::put_Java_u2(bcp+2, varNo);
2398 }
2399
2400 if (newIlen != ilen) {
2401 expand_current_instr(bcs->bci(), ilen, newIlen, inst_buffer);
2402 }
2403
2404
2405 return (newIlen != ilen);
2406 }
2407
2408 class RelocCallback : public RelocatorListener {
2409 private:
2410 GenerateOopMap* _gom;
2411 public:
2412 RelocCallback(GenerateOopMap* gom) { _gom = gom; };
2413
2414 // Callback method
2415 virtual void relocated(int bci, int delta, int new_code_length) {
2416 _gom->update_basic_blocks (bci, delta, new_code_length);
2417 _gom->update_ret_adr_at_TOS(bci, delta);
2418 _gom->_rt.update_ret_table (bci, delta);
2419 }
2420 };
2421
2422 // Returns true if expanding was succesful. Otherwise, reports an error and
2423 // returns false.
2424 void GenerateOopMap::expand_current_instr(int bci, int ilen, int newIlen, u_char inst_buffer[]) {
2425 Thread *THREAD = Thread::current(); // Could really have TRAPS argument.
2426 RelocCallback rcb(this);
2427 Relocator rc(_method, &rcb);
2428 methodHandle m= rc.insert_space_at(bci, newIlen, inst_buffer, THREAD);
2429 if (m.is_null() || HAS_PENDING_EXCEPTION) {
2430 report_error("could not rewrite method - exception occurred or bytecode buffer overflow");
2431 return;
2432 }
2433
2434 // Relocator returns a new method oop.
2435 _did_relocation = true;
2436 _method = m;
2437 }
2438
2439
2440 bool GenerateOopMap::is_astore(BytecodeStream *itr, int *index) {
2441 Bytecodes::Code bc = itr->code();
2442 switch(bc) {
2443 case Bytecodes::_astore_0:
2444 case Bytecodes::_astore_1:
2445 case Bytecodes::_astore_2:
2446 case Bytecodes::_astore_3:
2447 *index = bc - Bytecodes::_astore_0;
2448 return true;
2449 case Bytecodes::_astore:
2450 *index = itr->get_index();
2451 return true;
2452 }
2453 return false;
2454 }
2455
2456 bool GenerateOopMap::is_aload(BytecodeStream *itr, int *index) {
2457 Bytecodes::Code bc = itr->code();
2458 switch(bc) {
2459 case Bytecodes::_aload_0:
2460 case Bytecodes::_aload_1:
2461 case Bytecodes::_aload_2:
2462 case Bytecodes::_aload_3:
2463 *index = bc - Bytecodes::_aload_0;
2464 return true;
2465
2466 case Bytecodes::_aload:
2467 *index = itr->get_index();
2468 return true;
2469 }
2470 return false;
2471 }
2472
2473
2474 // Return true iff the top of the operand stack holds a return address at
2475 // the current instruction
2476 bool GenerateOopMap::stack_top_holds_ret_addr(int bci) {
2477 for(int i = 0; i < _ret_adr_tos->length(); i++) {
2478 if (_ret_adr_tos->at(i) == bci)
2479 return true;
2480 }
2481
2482 return false;
2483 }
2484
2485 void GenerateOopMap::compute_ret_adr_at_TOS() {
2486 assert(_ret_adr_tos != NULL, "must be initialized");
2487 _ret_adr_tos->clear();
2488
2489 for (int i = 0; i < bb_count(); i++) {
2490 BasicBlock* bb = &_basic_blocks[i];
2491
2492 // Make sure to only check basicblocks that are reachable
2493 if (bb->is_reachable()) {
2494
2495 // For each Basic block we check all instructions
2496 BytecodeStream bcs(_method);
2497 bcs.set_interval(bb->_bci, next_bb_start_pc(bb));
2498
2499 restore_state(bb);
2500
2501 while (bcs.next()>=0 && !_got_error) {
2502 // TDT: should this be is_good_address() ?
2503 if (_stack_top > 0 && stack()[_stack_top-1].is_address()) {
2504 _ret_adr_tos->append(bcs.bci());
2505 if (TraceNewOopMapGeneration) {
2506 tty->print_cr("Ret_adr TOS at bci: %d", bcs.bci());
2507 }
2508 }
2509 interp1(&bcs);
2510 }
2511 }
2512 }
2513 }
2514
2515 void GenerateOopMap::update_ret_adr_at_TOS(int bci, int delta) {
2516 for(int i = 0; i < _ret_adr_tos->length(); i++) {
2517 int v = _ret_adr_tos->at(i);
2518 if (v > bci) _ret_adr_tos->at_put(i, v + delta);
2519 }
2520 }
2521
2522 // ===================================================================
2523
2524 #ifndef PRODUCT
2525 int ResolveOopMapConflicts::_nof_invocations = 0;
2526 int ResolveOopMapConflicts::_nof_rewrites = 0;
2527 int ResolveOopMapConflicts::_nof_relocations = 0;
2528 #endif
2529
2530 methodHandle ResolveOopMapConflicts::do_potential_rewrite(TRAPS) {
2531 compute_map(CHECK_(methodHandle()));
2532
2533 #ifndef PRODUCT
2534 // Tracking and statistics
2535 if (PrintRewrites) {
2536 _nof_invocations++;
2537 if (did_rewriting()) {
2538 _nof_rewrites++;
2539 if (did_relocation()) _nof_relocations++;
2540 tty->print("Method was rewritten %s: ", (did_relocation()) ? "and relocated" : "");
2541 method()->print_value(); tty->cr();
2542 tty->print_cr("Cand.: %d rewrts: %d (%d%%) reloc.: %d (%d%%)",
2543 _nof_invocations,
2544 _nof_rewrites, (_nof_rewrites * 100) / _nof_invocations,
2545 _nof_relocations, (_nof_relocations * 100) / _nof_invocations);
2546 }
2547 }
2548 #endif
2549 return methodHandle(THREAD, method());
2550 }