1 /*
2 * Copyright (c) 2005, 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 "ci/bcEscapeAnalyzer.hpp"
27 #include "ci/ciConstant.hpp"
28 #include "ci/ciField.hpp"
29 #include "ci/ciMethodBlocks.hpp"
30 #include "ci/ciStreams.hpp"
31 #include "interpreter/bytecode.hpp"
32 #include "utilities/bitMap.inline.hpp"
33
34
35
36 #ifndef PRODUCT
37 #define TRACE_BCEA(level, code) \
38 if (EstimateArgEscape && BCEATraceLevel >= level) { \
39 code; \
40 }
41 #else
42 #define TRACE_BCEA(level, code)
43 #endif
44
45 // Maintain a map of which aguments a local variable or
46 // stack slot may contain. In addition to tracking
47 // arguments, it tracks two special values, "allocated"
48 // which represents any object allocated in the current
49 // method, and "unknown" which is any other object.
50 // Up to 30 arguments are handled, with the last one
51 // representing summary information for any extra arguments
52 class BCEscapeAnalyzer::ArgumentMap {
53 uint _bits;
54 enum {MAXBIT = 29,
55 ALLOCATED = 1,
56 UNKNOWN = 2};
57
58 uint int_to_bit(uint e) const {
59 if (e > MAXBIT)
60 e = MAXBIT;
61 return (1 << (e + 2));
62 }
63
64 public:
65 ArgumentMap() { _bits = 0;}
66 void set_bits(uint bits) { _bits = bits;}
67 uint get_bits() const { return _bits;}
68 void clear() { _bits = 0;}
69 void set_all() { _bits = ~0u; }
70 bool is_empty() const { return _bits == 0; }
71 bool contains(uint var) const { return (_bits & int_to_bit(var)) != 0; }
72 bool is_singleton(uint var) const { return (_bits == int_to_bit(var)); }
73 bool contains_unknown() const { return (_bits & UNKNOWN) != 0; }
74 bool contains_allocated() const { return (_bits & ALLOCATED) != 0; }
75 bool contains_vars() const { return (_bits & (((1 << MAXBIT) -1) << 2)) != 0; }
76 void set(uint var) { _bits = int_to_bit(var); }
77 void add(uint var) { _bits |= int_to_bit(var); }
78 void add_unknown() { _bits = UNKNOWN; }
79 void add_allocated() { _bits = ALLOCATED; }
80 void set_union(const ArgumentMap &am) { _bits |= am._bits; }
81 void set_intersect(const ArgumentMap &am) { _bits |= am._bits; }
82 void set_difference(const ArgumentMap &am) { _bits &= ~am._bits; }
83 void operator=(const ArgumentMap &am) { _bits = am._bits; }
84 bool operator==(const ArgumentMap &am) { return _bits == am._bits; }
85 bool operator!=(const ArgumentMap &am) { return _bits != am._bits; }
86 };
87
88 class BCEscapeAnalyzer::StateInfo {
89 public:
90 ArgumentMap *_vars;
91 ArgumentMap *_stack;
92 short _stack_height;
93 short _max_stack;
94 bool _initialized;
95 ArgumentMap empty_map;
96
97 StateInfo() {
98 empty_map.clear();
99 }
100
101 ArgumentMap raw_pop() { guarantee(_stack_height > 0, "stack underflow"); return _stack[--_stack_height]; }
102 ArgumentMap apop() { return raw_pop(); }
103 void spop() { raw_pop(); }
104 void lpop() { spop(); spop(); }
105 void raw_push(ArgumentMap i) { guarantee(_stack_height < _max_stack, "stack overflow"); _stack[_stack_height++] = i; }
106 void apush(ArgumentMap i) { raw_push(i); }
107 void spush() { raw_push(empty_map); }
108 void lpush() { spush(); spush(); }
109
110 };
111
112 void BCEscapeAnalyzer::set_returned(ArgumentMap vars) {
113 for (int i = 0; i < _arg_size; i++) {
114 if (vars.contains(i))
115 _arg_returned.set(i);
116 }
117 _return_local = _return_local && !(vars.contains_unknown() || vars.contains_allocated());
118 _return_allocated = _return_allocated && vars.contains_allocated() && !(vars.contains_unknown() || vars.contains_vars());
119 }
120
121 // return true if any element of vars is an argument
122 bool BCEscapeAnalyzer::is_argument(ArgumentMap vars) {
123 for (int i = 0; i < _arg_size; i++) {
124 if (vars.contains(i))
125 return true;
126 }
127 return false;
128 }
129
130 // return true if any element of vars is an arg_stack argument
131 bool BCEscapeAnalyzer::is_arg_stack(ArgumentMap vars){
132 if (_conservative)
133 return true;
134 for (int i = 0; i < _arg_size; i++) {
135 if (vars.contains(i) && _arg_stack.test(i))
136 return true;
137 }
138 return false;
139 }
140
141 // return true if all argument elements of vars are returned
142 bool BCEscapeAnalyzer::returns_all(ArgumentMap vars) {
143 for (int i = 0; i < _arg_size; i++) {
144 if (vars.contains(i) && !_arg_returned.test(i)) {
145 return false;
146 }
147 }
148 return true;
149 }
150
151 void BCEscapeAnalyzer::clear_bits(ArgumentMap vars, VectorSet &bm) {
152 for (int i = 0; i < _arg_size; i++) {
153 if (vars.contains(i)) {
154 bm >>= i;
155 }
156 }
157 }
158
159 void BCEscapeAnalyzer::set_method_escape(ArgumentMap vars) {
160 clear_bits(vars, _arg_local);
161 }
162
163 void BCEscapeAnalyzer::set_global_escape(ArgumentMap vars, bool merge) {
164 clear_bits(vars, _arg_local);
165 clear_bits(vars, _arg_stack);
166 if (vars.contains_allocated())
167 _allocated_escapes = true;
168
169 if (merge && !vars.is_empty()) {
170 // Merge new state into already processed block.
171 // New state is not taken into account and
172 // it may invalidate set_returned() result.
173 if (vars.contains_unknown() || vars.contains_allocated()) {
174 _return_local = false;
175 }
176 if (vars.contains_unknown() || vars.contains_vars()) {
177 _return_allocated = false;
178 }
179 if (_return_local && vars.contains_vars() && !returns_all(vars)) {
180 // Return result should be invalidated if args in new
181 // state are not recorded in return state.
182 _return_local = false;
183 }
184 }
185 }
186
187 void BCEscapeAnalyzer::set_dirty(ArgumentMap vars) {
188 clear_bits(vars, _dirty);
189 }
190
191 void BCEscapeAnalyzer::set_modified(ArgumentMap vars, int offs, int size) {
192
193 for (int i = 0; i < _arg_size; i++) {
194 if (vars.contains(i)) {
195 set_arg_modified(i, offs, size);
196 }
197 }
198 if (vars.contains_unknown())
199 _unknown_modified = true;
200 }
201
202 bool BCEscapeAnalyzer::is_recursive_call(ciMethod* callee) {
203 for (BCEscapeAnalyzer* scope = this; scope != NULL; scope = scope->_parent) {
204 if (scope->method() == callee) {
205 return true;
206 }
207 }
208 return false;
209 }
210
211 bool BCEscapeAnalyzer::is_arg_modified(int arg, int offset, int size_in_bytes) {
212 if (offset == OFFSET_ANY)
213 return _arg_modified[arg] != 0;
214 assert(arg >= 0 && arg < _arg_size, "must be an argument.");
215 bool modified = false;
216 int l = offset / HeapWordSize;
217 int h = round_to(offset + size_in_bytes, HeapWordSize) / HeapWordSize;
218 if (l > ARG_OFFSET_MAX)
219 l = ARG_OFFSET_MAX;
220 if (h > ARG_OFFSET_MAX+1)
221 h = ARG_OFFSET_MAX + 1;
222 for (int i = l; i < h; i++) {
223 modified = modified || (_arg_modified[arg] & (1 << i)) != 0;
224 }
225 return modified;
226 }
227
228 void BCEscapeAnalyzer::set_arg_modified(int arg, int offset, int size_in_bytes) {
229 if (offset == OFFSET_ANY) {
230 _arg_modified[arg] = (uint) -1;
231 return;
232 }
233 assert(arg >= 0 && arg < _arg_size, "must be an argument.");
234 int l = offset / HeapWordSize;
235 int h = round_to(offset + size_in_bytes, HeapWordSize) / HeapWordSize;
236 if (l > ARG_OFFSET_MAX)
237 l = ARG_OFFSET_MAX;
238 if (h > ARG_OFFSET_MAX+1)
239 h = ARG_OFFSET_MAX + 1;
240 for (int i = l; i < h; i++) {
241 _arg_modified[arg] |= (1 << i);
242 }
243 }
244
245 void BCEscapeAnalyzer::invoke(StateInfo &state, Bytecodes::Code code, ciMethod* target, ciKlass* holder) {
246 int i;
247
248 // retrieve information about the callee
249 ciInstanceKlass* klass = target->holder();
250 ciInstanceKlass* calling_klass = method()->holder();
251 ciInstanceKlass* callee_holder = ciEnv::get_instance_klass_for_declared_method_holder(holder);
252 ciInstanceKlass* actual_recv = callee_holder;
253
254 // Some methods are obviously bindable without any type checks so
255 // convert them directly to an invokespecial or invokestatic.
256 if (target->is_loaded() && !target->is_abstract() && target->can_be_statically_bound()) {
257 switch (code) {
258 case Bytecodes::_invokevirtual:
259 code = Bytecodes::_invokespecial;
260 break;
261 case Bytecodes::_invokehandle:
262 code = target->is_static() ? Bytecodes::_invokestatic : Bytecodes::_invokespecial;
263 break;
264 }
265 }
266
267 // compute size of arguments
268 int arg_size = target->invoke_arg_size(code);
269 int arg_base = MAX2(state._stack_height - arg_size, 0);
270
271 // direct recursive calls are skipped if they can be bound statically without introducing
272 // dependencies and if parameters are passed at the same position as in the current method
273 // other calls are skipped if there are no unescaped arguments passed to them
274 bool directly_recursive = (method() == target) &&
275 (code != Bytecodes::_invokevirtual || target->is_final_method() || state._stack[arg_base] .is_empty());
276
277 // check if analysis of callee can safely be skipped
278 bool skip_callee = true;
279 for (i = state._stack_height - 1; i >= arg_base && skip_callee; i--) {
280 ArgumentMap arg = state._stack[i];
281 skip_callee = !is_argument(arg) || !is_arg_stack(arg) || (directly_recursive && arg.is_singleton(i - arg_base));
282 }
283 // For now we conservatively skip invokedynamic.
284 if (code == Bytecodes::_invokedynamic) {
285 skip_callee = true;
286 }
287 if (skip_callee) {
288 TRACE_BCEA(3, tty->print_cr("[EA] skipping method %s::%s", holder->name()->as_utf8(), target->name()->as_utf8()));
289 for (i = 0; i < arg_size; i++) {
290 set_method_escape(state.raw_pop());
291 }
292 _unknown_modified = true; // assume the worst since we don't analyze the called method
293 return;
294 }
295
296 // determine actual method (use CHA if necessary)
297 ciMethod* inline_target = NULL;
298 if (target->is_loaded() && klass->is_loaded()
299 && (klass->is_initialized() || klass->is_interface() && target->holder()->is_initialized())
300 && target->is_loaded()) {
301 if (code == Bytecodes::_invokestatic
302 || code == Bytecodes::_invokespecial
303 || code == Bytecodes::_invokevirtual && target->is_final_method()) {
304 inline_target = target;
305 } else {
306 inline_target = target->find_monomorphic_target(calling_klass, callee_holder, actual_recv);
307 }
308 }
309
310 if (inline_target != NULL && !is_recursive_call(inline_target)) {
311 // analyze callee
312 BCEscapeAnalyzer analyzer(inline_target, this);
313
314 // adjust escape state of actual parameters
315 bool must_record_dependencies = false;
316 for (i = arg_size - 1; i >= 0; i--) {
317 ArgumentMap arg = state.raw_pop();
318 if (!is_argument(arg))
319 continue;
320 for (int j = 0; j < _arg_size; j++) {
321 if (arg.contains(j)) {
322 _arg_modified[j] |= analyzer._arg_modified[i];
323 }
324 }
325 if (!is_arg_stack(arg)) {
326 // arguments have already been recognized as escaping
327 } else if (analyzer.is_arg_stack(i) && !analyzer.is_arg_returned(i)) {
328 set_method_escape(arg);
329 must_record_dependencies = true;
330 } else {
331 set_global_escape(arg);
332 }
333 }
334 _unknown_modified = _unknown_modified || analyzer.has_non_arg_side_affects();
335
336 // record dependencies if at least one parameter retained stack-allocatable
337 if (must_record_dependencies) {
338 if (code == Bytecodes::_invokeinterface || code == Bytecodes::_invokevirtual && !target->is_final_method()) {
339 _dependencies.append(actual_recv);
340 _dependencies.append(inline_target);
341 }
342 _dependencies.appendAll(analyzer.dependencies());
343 }
344 } else {
345 TRACE_BCEA(1, tty->print_cr("[EA] virtual method %s is not monomorphic.",
346 target->name()->as_utf8()));
347 // conservatively mark all actual parameters as escaping globally
348 for (i = 0; i < arg_size; i++) {
349 ArgumentMap arg = state.raw_pop();
350 if (!is_argument(arg))
351 continue;
352 set_modified(arg, OFFSET_ANY, type2size[T_INT]*HeapWordSize);
353 set_global_escape(arg);
354 }
355 _unknown_modified = true; // assume the worst since we don't know the called method
356 }
357 }
358
359 bool BCEscapeAnalyzer::contains(uint arg_set1, uint arg_set2) {
360 return ((~arg_set1) | arg_set2) == 0;
361 }
362
363
364 void BCEscapeAnalyzer::iterate_one_block(ciBlock *blk, StateInfo &state, GrowableArray<ciBlock *> &successors) {
365
366 blk->set_processed();
367 ciBytecodeStream s(method());
368 int limit_bci = blk->limit_bci();
369 bool fall_through = false;
370 ArgumentMap allocated_obj;
371 allocated_obj.add_allocated();
372 ArgumentMap unknown_obj;
373 unknown_obj.add_unknown();
374 ArgumentMap empty_map;
375
376 s.reset_to_bci(blk->start_bci());
377 while (s.next() != ciBytecodeStream::EOBC() && s.cur_bci() < limit_bci) {
378 fall_through = true;
379 switch (s.cur_bc()) {
380 case Bytecodes::_nop:
381 break;
382 case Bytecodes::_aconst_null:
383 state.apush(unknown_obj);
384 break;
385 case Bytecodes::_iconst_m1:
386 case Bytecodes::_iconst_0:
387 case Bytecodes::_iconst_1:
388 case Bytecodes::_iconst_2:
389 case Bytecodes::_iconst_3:
390 case Bytecodes::_iconst_4:
391 case Bytecodes::_iconst_5:
392 case Bytecodes::_fconst_0:
393 case Bytecodes::_fconst_1:
394 case Bytecodes::_fconst_2:
395 case Bytecodes::_bipush:
396 case Bytecodes::_sipush:
397 state.spush();
398 break;
399 case Bytecodes::_lconst_0:
400 case Bytecodes::_lconst_1:
401 case Bytecodes::_dconst_0:
402 case Bytecodes::_dconst_1:
403 state.lpush();
404 break;
405 case Bytecodes::_ldc:
406 case Bytecodes::_ldc_w:
407 case Bytecodes::_ldc2_w:
408 {
409 // Avoid calling get_constant() which will try to allocate
410 // unloaded constant. We need only constant's type.
411 int index = s.get_constant_pool_index();
412 constantTag tag = s.get_constant_pool_tag(index);
413 if (tag.is_long() || tag.is_double()) {
414 // Only longs and doubles use 2 stack slots.
415 state.lpush();
416 } else if (tag.basic_type() == T_OBJECT) {
417 state.apush(unknown_obj);
418 } else {
419 state.spush();
420 }
421 break;
422 }
423 case Bytecodes::_aload:
424 state.apush(state._vars[s.get_index()]);
425 break;
426 case Bytecodes::_iload:
427 case Bytecodes::_fload:
428 case Bytecodes::_iload_0:
429 case Bytecodes::_iload_1:
430 case Bytecodes::_iload_2:
431 case Bytecodes::_iload_3:
432 case Bytecodes::_fload_0:
433 case Bytecodes::_fload_1:
434 case Bytecodes::_fload_2:
435 case Bytecodes::_fload_3:
436 state.spush();
437 break;
438 case Bytecodes::_lload:
439 case Bytecodes::_dload:
440 case Bytecodes::_lload_0:
441 case Bytecodes::_lload_1:
442 case Bytecodes::_lload_2:
443 case Bytecodes::_lload_3:
444 case Bytecodes::_dload_0:
445 case Bytecodes::_dload_1:
446 case Bytecodes::_dload_2:
447 case Bytecodes::_dload_3:
448 state.lpush();
449 break;
450 case Bytecodes::_aload_0:
451 state.apush(state._vars[0]);
452 break;
453 case Bytecodes::_aload_1:
454 state.apush(state._vars[1]);
455 break;
456 case Bytecodes::_aload_2:
457 state.apush(state._vars[2]);
458 break;
459 case Bytecodes::_aload_3:
460 state.apush(state._vars[3]);
461 break;
462 case Bytecodes::_iaload:
463 case Bytecodes::_faload:
464 case Bytecodes::_baload:
465 case Bytecodes::_caload:
466 case Bytecodes::_saload:
467 state.spop();
468 set_method_escape(state.apop());
469 state.spush();
470 break;
471 case Bytecodes::_laload:
472 case Bytecodes::_daload:
473 state.spop();
474 set_method_escape(state.apop());
475 state.lpush();
476 break;
477 case Bytecodes::_aaload:
478 { state.spop();
479 ArgumentMap array = state.apop();
480 set_method_escape(array);
481 state.apush(unknown_obj);
482 set_dirty(array);
483 }
484 break;
485 case Bytecodes::_istore:
486 case Bytecodes::_fstore:
487 case Bytecodes::_istore_0:
488 case Bytecodes::_istore_1:
489 case Bytecodes::_istore_2:
490 case Bytecodes::_istore_3:
491 case Bytecodes::_fstore_0:
492 case Bytecodes::_fstore_1:
493 case Bytecodes::_fstore_2:
494 case Bytecodes::_fstore_3:
495 state.spop();
496 break;
497 case Bytecodes::_lstore:
498 case Bytecodes::_dstore:
499 case Bytecodes::_lstore_0:
500 case Bytecodes::_lstore_1:
501 case Bytecodes::_lstore_2:
502 case Bytecodes::_lstore_3:
503 case Bytecodes::_dstore_0:
504 case Bytecodes::_dstore_1:
505 case Bytecodes::_dstore_2:
506 case Bytecodes::_dstore_3:
507 state.lpop();
508 break;
509 case Bytecodes::_astore:
510 state._vars[s.get_index()] = state.apop();
511 break;
512 case Bytecodes::_astore_0:
513 state._vars[0] = state.apop();
514 break;
515 case Bytecodes::_astore_1:
516 state._vars[1] = state.apop();
517 break;
518 case Bytecodes::_astore_2:
519 state._vars[2] = state.apop();
520 break;
521 case Bytecodes::_astore_3:
522 state._vars[3] = state.apop();
523 break;
524 case Bytecodes::_iastore:
525 case Bytecodes::_fastore:
526 case Bytecodes::_bastore:
527 case Bytecodes::_castore:
528 case Bytecodes::_sastore:
529 {
530 state.spop();
531 state.spop();
532 ArgumentMap arr = state.apop();
533 set_method_escape(arr);
534 set_modified(arr, OFFSET_ANY, type2size[T_INT]*HeapWordSize);
535 break;
536 }
537 case Bytecodes::_lastore:
538 case Bytecodes::_dastore:
539 {
540 state.lpop();
541 state.spop();
542 ArgumentMap arr = state.apop();
543 set_method_escape(arr);
544 set_modified(arr, OFFSET_ANY, type2size[T_LONG]*HeapWordSize);
545 break;
546 }
547 case Bytecodes::_aastore:
548 {
549 set_global_escape(state.apop());
550 state.spop();
551 ArgumentMap arr = state.apop();
552 set_modified(arr, OFFSET_ANY, type2size[T_OBJECT]*HeapWordSize);
553 break;
554 }
555 case Bytecodes::_pop:
556 state.raw_pop();
557 break;
558 case Bytecodes::_pop2:
559 state.raw_pop();
560 state.raw_pop();
561 break;
562 case Bytecodes::_dup:
563 { ArgumentMap w1 = state.raw_pop();
564 state.raw_push(w1);
565 state.raw_push(w1);
566 }
567 break;
568 case Bytecodes::_dup_x1:
569 { ArgumentMap w1 = state.raw_pop();
570 ArgumentMap w2 = state.raw_pop();
571 state.raw_push(w1);
572 state.raw_push(w2);
573 state.raw_push(w1);
574 }
575 break;
576 case Bytecodes::_dup_x2:
577 { ArgumentMap w1 = state.raw_pop();
578 ArgumentMap w2 = state.raw_pop();
579 ArgumentMap w3 = state.raw_pop();
580 state.raw_push(w1);
581 state.raw_push(w3);
582 state.raw_push(w2);
583 state.raw_push(w1);
584 }
585 break;
586 case Bytecodes::_dup2:
587 { ArgumentMap w1 = state.raw_pop();
588 ArgumentMap w2 = state.raw_pop();
589 state.raw_push(w2);
590 state.raw_push(w1);
591 state.raw_push(w2);
592 state.raw_push(w1);
593 }
594 break;
595 case Bytecodes::_dup2_x1:
596 { ArgumentMap w1 = state.raw_pop();
597 ArgumentMap w2 = state.raw_pop();
598 ArgumentMap w3 = state.raw_pop();
599 state.raw_push(w2);
600 state.raw_push(w1);
601 state.raw_push(w3);
602 state.raw_push(w2);
603 state.raw_push(w1);
604 }
605 break;
606 case Bytecodes::_dup2_x2:
607 { ArgumentMap w1 = state.raw_pop();
608 ArgumentMap w2 = state.raw_pop();
609 ArgumentMap w3 = state.raw_pop();
610 ArgumentMap w4 = state.raw_pop();
611 state.raw_push(w2);
612 state.raw_push(w1);
613 state.raw_push(w4);
614 state.raw_push(w3);
615 state.raw_push(w2);
616 state.raw_push(w1);
617 }
618 break;
619 case Bytecodes::_swap:
620 { ArgumentMap w1 = state.raw_pop();
621 ArgumentMap w2 = state.raw_pop();
622 state.raw_push(w1);
623 state.raw_push(w2);
624 }
625 break;
626 case Bytecodes::_iadd:
627 case Bytecodes::_fadd:
628 case Bytecodes::_isub:
629 case Bytecodes::_fsub:
630 case Bytecodes::_imul:
631 case Bytecodes::_fmul:
632 case Bytecodes::_idiv:
633 case Bytecodes::_fdiv:
634 case Bytecodes::_irem:
635 case Bytecodes::_frem:
636 case Bytecodes::_iand:
637 case Bytecodes::_ior:
638 case Bytecodes::_ixor:
639 state.spop();
640 state.spop();
641 state.spush();
642 break;
643 case Bytecodes::_ladd:
644 case Bytecodes::_dadd:
645 case Bytecodes::_lsub:
646 case Bytecodes::_dsub:
647 case Bytecodes::_lmul:
648 case Bytecodes::_dmul:
649 case Bytecodes::_ldiv:
650 case Bytecodes::_ddiv:
651 case Bytecodes::_lrem:
652 case Bytecodes::_drem:
653 case Bytecodes::_land:
654 case Bytecodes::_lor:
655 case Bytecodes::_lxor:
656 state.lpop();
657 state.lpop();
658 state.lpush();
659 break;
660 case Bytecodes::_ishl:
661 case Bytecodes::_ishr:
662 case Bytecodes::_iushr:
663 state.spop();
664 state.spop();
665 state.spush();
666 break;
667 case Bytecodes::_lshl:
668 case Bytecodes::_lshr:
669 case Bytecodes::_lushr:
670 state.spop();
671 state.lpop();
672 state.lpush();
673 break;
674 case Bytecodes::_ineg:
675 case Bytecodes::_fneg:
676 state.spop();
677 state.spush();
678 break;
679 case Bytecodes::_lneg:
680 case Bytecodes::_dneg:
681 state.lpop();
682 state.lpush();
683 break;
684 case Bytecodes::_iinc:
685 break;
686 case Bytecodes::_i2l:
687 case Bytecodes::_i2d:
688 case Bytecodes::_f2l:
689 case Bytecodes::_f2d:
690 state.spop();
691 state.lpush();
692 break;
693 case Bytecodes::_i2f:
694 case Bytecodes::_f2i:
695 state.spop();
696 state.spush();
697 break;
698 case Bytecodes::_l2i:
699 case Bytecodes::_l2f:
700 case Bytecodes::_d2i:
701 case Bytecodes::_d2f:
702 state.lpop();
703 state.spush();
704 break;
705 case Bytecodes::_l2d:
706 case Bytecodes::_d2l:
707 state.lpop();
708 state.lpush();
709 break;
710 case Bytecodes::_i2b:
711 case Bytecodes::_i2c:
712 case Bytecodes::_i2s:
713 state.spop();
714 state.spush();
715 break;
716 case Bytecodes::_lcmp:
717 case Bytecodes::_dcmpl:
718 case Bytecodes::_dcmpg:
719 state.lpop();
720 state.lpop();
721 state.spush();
722 break;
723 case Bytecodes::_fcmpl:
724 case Bytecodes::_fcmpg:
725 state.spop();
726 state.spop();
727 state.spush();
728 break;
729 case Bytecodes::_ifeq:
730 case Bytecodes::_ifne:
731 case Bytecodes::_iflt:
732 case Bytecodes::_ifge:
733 case Bytecodes::_ifgt:
734 case Bytecodes::_ifle:
735 {
736 state.spop();
737 int dest_bci = s.get_dest();
738 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
739 assert(s.next_bci() == limit_bci, "branch must end block");
740 successors.push(_methodBlocks->block_containing(dest_bci));
741 break;
742 }
743 case Bytecodes::_if_icmpeq:
744 case Bytecodes::_if_icmpne:
745 case Bytecodes::_if_icmplt:
746 case Bytecodes::_if_icmpge:
747 case Bytecodes::_if_icmpgt:
748 case Bytecodes::_if_icmple:
749 {
750 state.spop();
751 state.spop();
752 int dest_bci = s.get_dest();
753 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
754 assert(s.next_bci() == limit_bci, "branch must end block");
755 successors.push(_methodBlocks->block_containing(dest_bci));
756 break;
757 }
758 case Bytecodes::_if_acmpeq:
759 case Bytecodes::_if_acmpne:
760 {
761 set_method_escape(state.apop());
762 set_method_escape(state.apop());
763 int dest_bci = s.get_dest();
764 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
765 assert(s.next_bci() == limit_bci, "branch must end block");
766 successors.push(_methodBlocks->block_containing(dest_bci));
767 break;
768 }
769 case Bytecodes::_goto:
770 {
771 int dest_bci = s.get_dest();
772 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
773 assert(s.next_bci() == limit_bci, "branch must end block");
774 successors.push(_methodBlocks->block_containing(dest_bci));
775 fall_through = false;
776 break;
777 }
778 case Bytecodes::_jsr:
779 {
780 int dest_bci = s.get_dest();
781 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
782 assert(s.next_bci() == limit_bci, "branch must end block");
783 state.apush(empty_map);
784 successors.push(_methodBlocks->block_containing(dest_bci));
785 fall_through = false;
786 break;
787 }
788 case Bytecodes::_ret:
789 // we don't track the destination of a "ret" instruction
790 assert(s.next_bci() == limit_bci, "branch must end block");
791 fall_through = false;
792 break;
793 case Bytecodes::_return:
794 assert(s.next_bci() == limit_bci, "return must end block");
795 fall_through = false;
796 break;
797 case Bytecodes::_tableswitch:
798 {
799 state.spop();
800 Bytecode_tableswitch sw(&s);
801 int len = sw.length();
802 int dest_bci;
803 for (int i = 0; i < len; i++) {
804 dest_bci = s.cur_bci() + sw.dest_offset_at(i);
805 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
806 successors.push(_methodBlocks->block_containing(dest_bci));
807 }
808 dest_bci = s.cur_bci() + sw.default_offset();
809 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
810 successors.push(_methodBlocks->block_containing(dest_bci));
811 assert(s.next_bci() == limit_bci, "branch must end block");
812 fall_through = false;
813 break;
814 }
815 case Bytecodes::_lookupswitch:
816 {
817 state.spop();
818 Bytecode_lookupswitch sw(&s);
819 int len = sw.number_of_pairs();
820 int dest_bci;
821 for (int i = 0; i < len; i++) {
822 dest_bci = s.cur_bci() + sw.pair_at(i).offset();
823 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
824 successors.push(_methodBlocks->block_containing(dest_bci));
825 }
826 dest_bci = s.cur_bci() + sw.default_offset();
827 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
828 successors.push(_methodBlocks->block_containing(dest_bci));
829 fall_through = false;
830 break;
831 }
832 case Bytecodes::_ireturn:
833 case Bytecodes::_freturn:
834 state.spop();
835 fall_through = false;
836 break;
837 case Bytecodes::_lreturn:
838 case Bytecodes::_dreturn:
839 state.lpop();
840 fall_through = false;
841 break;
842 case Bytecodes::_areturn:
843 set_returned(state.apop());
844 fall_through = false;
845 break;
846 case Bytecodes::_getstatic:
847 case Bytecodes::_getfield:
848 { bool ignored_will_link;
849 ciField* field = s.get_field(ignored_will_link);
850 BasicType field_type = field->type()->basic_type();
851 if (s.cur_bc() != Bytecodes::_getstatic) {
852 set_method_escape(state.apop());
853 }
854 if (field_type == T_OBJECT || field_type == T_ARRAY) {
855 state.apush(unknown_obj);
856 } else if (type2size[field_type] == 1) {
857 state.spush();
858 } else {
859 state.lpush();
860 }
861 }
862 break;
863 case Bytecodes::_putstatic:
864 case Bytecodes::_putfield:
865 { bool will_link;
866 ciField* field = s.get_field(will_link);
867 BasicType field_type = field->type()->basic_type();
868 if (field_type == T_OBJECT || field_type == T_ARRAY) {
869 set_global_escape(state.apop());
870 } else if (type2size[field_type] == 1) {
871 state.spop();
872 } else {
873 state.lpop();
874 }
875 if (s.cur_bc() != Bytecodes::_putstatic) {
876 ArgumentMap p = state.apop();
877 set_method_escape(p);
878 set_modified(p, will_link ? field->offset() : OFFSET_ANY, type2size[field_type]*HeapWordSize);
879 }
880 }
881 break;
882 case Bytecodes::_invokevirtual:
883 case Bytecodes::_invokespecial:
884 case Bytecodes::_invokestatic:
885 case Bytecodes::_invokedynamic:
886 case Bytecodes::_invokeinterface:
887 { bool ignored_will_link;
888 ciSignature* declared_signature = NULL;
889 ciMethod* target = s.get_method(ignored_will_link, &declared_signature);
890 ciKlass* holder = s.get_declared_method_holder();
891 assert(declared_signature != NULL, "cannot be null");
892 // Push appendix argument, if one.
893 if (s.has_appendix()) {
894 state.apush(unknown_obj);
895 }
896 // Pass in raw bytecode because we need to see invokehandle instructions.
897 invoke(state, s.cur_bc_raw(), target, holder);
898 // We are using the return type of the declared signature here because
899 // it might be a more concrete type than the one from the target (for
900 // e.g. invokedynamic and invokehandle).
901 ciType* return_type = declared_signature->return_type();
902 if (!return_type->is_primitive_type()) {
903 state.apush(unknown_obj);
904 } else if (return_type->is_one_word()) {
905 state.spush();
906 } else if (return_type->is_two_word()) {
907 state.lpush();
908 }
909 }
910 break;
911 case Bytecodes::_new:
912 state.apush(allocated_obj);
913 break;
914 case Bytecodes::_newarray:
915 case Bytecodes::_anewarray:
916 state.spop();
917 state.apush(allocated_obj);
918 break;
919 case Bytecodes::_multianewarray:
920 { int i = s.cur_bcp()[3];
921 while (i-- > 0) state.spop();
922 state.apush(allocated_obj);
923 }
924 break;
925 case Bytecodes::_arraylength:
926 set_method_escape(state.apop());
927 state.spush();
928 break;
929 case Bytecodes::_athrow:
930 set_global_escape(state.apop());
931 fall_through = false;
932 break;
933 case Bytecodes::_checkcast:
934 { ArgumentMap obj = state.apop();
935 set_method_escape(obj);
936 state.apush(obj);
937 }
938 break;
939 case Bytecodes::_instanceof:
940 set_method_escape(state.apop());
941 state.spush();
942 break;
943 case Bytecodes::_monitorenter:
944 case Bytecodes::_monitorexit:
945 state.apop();
946 break;
947 case Bytecodes::_wide:
948 ShouldNotReachHere();
949 break;
950 case Bytecodes::_ifnull:
951 case Bytecodes::_ifnonnull:
952 {
953 set_method_escape(state.apop());
954 int dest_bci = s.get_dest();
955 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
956 assert(s.next_bci() == limit_bci, "branch must end block");
957 successors.push(_methodBlocks->block_containing(dest_bci));
958 break;
959 }
960 case Bytecodes::_goto_w:
961 {
962 int dest_bci = s.get_far_dest();
963 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
964 assert(s.next_bci() == limit_bci, "branch must end block");
965 successors.push(_methodBlocks->block_containing(dest_bci));
966 fall_through = false;
967 break;
968 }
969 case Bytecodes::_jsr_w:
970 {
971 int dest_bci = s.get_far_dest();
972 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
973 assert(s.next_bci() == limit_bci, "branch must end block");
974 state.apush(empty_map);
975 successors.push(_methodBlocks->block_containing(dest_bci));
976 fall_through = false;
977 break;
978 }
979 case Bytecodes::_breakpoint:
980 break;
981 default:
982 ShouldNotReachHere();
983 break;
984 }
985
986 }
987 if (fall_through) {
988 int fall_through_bci = s.cur_bci();
989 if (fall_through_bci < _method->code_size()) {
990 assert(_methodBlocks->is_block_start(fall_through_bci), "must fall through to block start.");
991 successors.push(_methodBlocks->block_containing(fall_through_bci));
992 }
993 }
994 }
995
996 void BCEscapeAnalyzer::merge_block_states(StateInfo *blockstates, ciBlock *dest, StateInfo *s_state) {
997 StateInfo *d_state = blockstates + dest->index();
998 int nlocals = _method->max_locals();
999
1000 // exceptions may cause transfer of control to handlers in the middle of a
1001 // block, so we don't merge the incoming state of exception handlers
1002 if (dest->is_handler())
1003 return;
1004 if (!d_state->_initialized ) {
1005 // destination not initialized, just copy
1006 for (int i = 0; i < nlocals; i++) {
1007 d_state->_vars[i] = s_state->_vars[i];
1008 }
1009 for (int i = 0; i < s_state->_stack_height; i++) {
1010 d_state->_stack[i] = s_state->_stack[i];
1011 }
1012 d_state->_stack_height = s_state->_stack_height;
1013 d_state->_max_stack = s_state->_max_stack;
1014 d_state->_initialized = true;
1015 } else if (!dest->processed()) {
1016 // we have not yet walked the bytecodes of dest, we can merge
1017 // the states
1018 assert(d_state->_stack_height == s_state->_stack_height, "computed stack heights must match");
1019 for (int i = 0; i < nlocals; i++) {
1020 d_state->_vars[i].set_union(s_state->_vars[i]);
1021 }
1022 for (int i = 0; i < s_state->_stack_height; i++) {
1023 d_state->_stack[i].set_union(s_state->_stack[i]);
1024 }
1025 } else {
1026 // the bytecodes of dest have already been processed, mark any
1027 // arguments in the source state which are not in the dest state
1028 // as global escape.
1029 // Future refinement: we only need to mark these variable to the
1030 // maximum escape of any variables in dest state
1031 assert(d_state->_stack_height == s_state->_stack_height, "computed stack heights must match");
1032 ArgumentMap extra_vars;
1033 for (int i = 0; i < nlocals; i++) {
1034 ArgumentMap t;
1035 t = s_state->_vars[i];
1036 t.set_difference(d_state->_vars[i]);
1037 extra_vars.set_union(t);
1038 }
1039 for (int i = 0; i < s_state->_stack_height; i++) {
1040 ArgumentMap t;
1041 //extra_vars |= !d_state->_vars[i] & s_state->_vars[i];
1042 t.clear();
1043 t = s_state->_stack[i];
1044 t.set_difference(d_state->_stack[i]);
1045 extra_vars.set_union(t);
1046 }
1047 set_global_escape(extra_vars, true);
1048 }
1049 }
1050
1051 void BCEscapeAnalyzer::iterate_blocks(Arena *arena) {
1052 int numblocks = _methodBlocks->num_blocks();
1053 int stkSize = _method->max_stack();
1054 int numLocals = _method->max_locals();
1055 StateInfo state;
1056
1057 int datacount = (numblocks + 1) * (stkSize + numLocals);
1058 int datasize = datacount * sizeof(ArgumentMap);
1059 StateInfo *blockstates = (StateInfo *) arena->Amalloc(numblocks * sizeof(StateInfo));
1060 ArgumentMap *statedata = (ArgumentMap *) arena->Amalloc(datasize);
1061 for (int i = 0; i < datacount; i++) ::new ((void*)&statedata[i]) ArgumentMap();
1062 ArgumentMap *dp = statedata;
1063 state._vars = dp;
1064 dp += numLocals;
1065 state._stack = dp;
1066 dp += stkSize;
1067 state._initialized = false;
1068 state._max_stack = stkSize;
1069 for (int i = 0; i < numblocks; i++) {
1070 blockstates[i]._vars = dp;
1071 dp += numLocals;
1072 blockstates[i]._stack = dp;
1073 dp += stkSize;
1074 blockstates[i]._initialized = false;
1075 blockstates[i]._stack_height = 0;
1076 blockstates[i]._max_stack = stkSize;
1077 }
1078 GrowableArray<ciBlock *> worklist(arena, numblocks / 4, 0, NULL);
1079 GrowableArray<ciBlock *> successors(arena, 4, 0, NULL);
1080
1081 _methodBlocks->clear_processed();
1082
1083 // initialize block 0 state from method signature
1084 ArgumentMap allVars; // all oop arguments to method
1085 ciSignature* sig = method()->signature();
1086 int j = 0;
1087 ciBlock* first_blk = _methodBlocks->block_containing(0);
1088 int fb_i = first_blk->index();
1089 if (!method()->is_static()) {
1090 // record information for "this"
1091 blockstates[fb_i]._vars[j].set(j);
1092 allVars.add(j);
1093 j++;
1094 }
1095 for (int i = 0; i < sig->count(); i++) {
1096 ciType* t = sig->type_at(i);
1097 if (!t->is_primitive_type()) {
1098 blockstates[fb_i]._vars[j].set(j);
1099 allVars.add(j);
1100 }
1101 j += t->size();
1102 }
1103 blockstates[fb_i]._initialized = true;
1104 assert(j == _arg_size, "just checking");
1105
1106 ArgumentMap unknown_map;
1107 unknown_map.add_unknown();
1108
1109 worklist.push(first_blk);
1110 while(worklist.length() > 0) {
1111 ciBlock *blk = worklist.pop();
1112 StateInfo *blkState = blockstates + blk->index();
1113 if (blk->is_handler() || blk->is_ret_target()) {
1114 // for an exception handler or a target of a ret instruction, we assume the worst case,
1115 // that any variable could contain any argument
1116 for (int i = 0; i < numLocals; i++) {
1117 state._vars[i] = allVars;
1118 }
1119 if (blk->is_handler()) {
1120 state._stack_height = 1;
1121 } else {
1122 state._stack_height = blkState->_stack_height;
1123 }
1124 for (int i = 0; i < state._stack_height; i++) {
1125 // ??? should this be unknown_map ???
1126 state._stack[i] = allVars;
1127 }
1128 } else {
1129 for (int i = 0; i < numLocals; i++) {
1130 state._vars[i] = blkState->_vars[i];
1131 }
1132 for (int i = 0; i < blkState->_stack_height; i++) {
1133 state._stack[i] = blkState->_stack[i];
1134 }
1135 state._stack_height = blkState->_stack_height;
1136 }
1137 iterate_one_block(blk, state, successors);
1138 // if this block has any exception handlers, push them
1139 // onto successor list
1140 if (blk->has_handler()) {
1141 DEBUG_ONLY(int handler_count = 0;)
1142 int blk_start = blk->start_bci();
1143 int blk_end = blk->limit_bci();
1144 for (int i = 0; i < numblocks; i++) {
1145 ciBlock *b = _methodBlocks->block(i);
1146 if (b->is_handler()) {
1147 int ex_start = b->ex_start_bci();
1148 int ex_end = b->ex_limit_bci();
1149 if ((ex_start >= blk_start && ex_start < blk_end) ||
1150 (ex_end > blk_start && ex_end <= blk_end)) {
1151 successors.push(b);
1152 }
1153 DEBUG_ONLY(handler_count++;)
1154 }
1155 }
1156 assert(handler_count > 0, "must find at least one handler");
1157 }
1158 // merge computed variable state with successors
1159 while(successors.length() > 0) {
1160 ciBlock *succ = successors.pop();
1161 merge_block_states(blockstates, succ, &state);
1162 if (!succ->processed())
1163 worklist.push(succ);
1164 }
1165 }
1166 }
1167
1168 bool BCEscapeAnalyzer::do_analysis() {
1169 Arena* arena = CURRENT_ENV->arena();
1170 // identify basic blocks
1171 _methodBlocks = _method->get_method_blocks();
1172
1173 iterate_blocks(arena);
1174 // TEMPORARY
1175 return true;
1176 }
1177
1178 vmIntrinsics::ID BCEscapeAnalyzer::known_intrinsic() {
1179 vmIntrinsics::ID iid = method()->intrinsic_id();
1180
1181 if (iid == vmIntrinsics::_getClass ||
1182 iid == vmIntrinsics::_fillInStackTrace ||
1183 iid == vmIntrinsics::_hashCode)
1184 return iid;
1185 else
1186 return vmIntrinsics::_none;
1187 }
1188
1189 bool BCEscapeAnalyzer::compute_escape_for_intrinsic(vmIntrinsics::ID iid) {
1190 ArgumentMap arg;
1191 arg.clear();
1192 switch (iid) {
1193 case vmIntrinsics::_getClass:
1194 _return_local = false;
1195 break;
1196 case vmIntrinsics::_fillInStackTrace:
1197 arg.set(0); // 'this'
1198 set_returned(arg);
1199 break;
1200 case vmIntrinsics::_hashCode:
1201 // initialized state is correct
1202 break;
1203 default:
1204 assert(false, "unexpected intrinsic");
1205 }
1206 return true;
1207 }
1208
1209 void BCEscapeAnalyzer::initialize() {
1210 int i;
1211
1212 // clear escape information (method may have been deoptimized)
1213 methodData()->clear_escape_info();
1214
1215 // initialize escape state of object parameters
1216 ciSignature* sig = method()->signature();
1217 int j = 0;
1218 if (!method()->is_static()) {
1219 _arg_local.set(0);
1220 _arg_stack.set(0);
1221 j++;
1222 }
1223 for (i = 0; i < sig->count(); i++) {
1224 ciType* t = sig->type_at(i);
1225 if (!t->is_primitive_type()) {
1226 _arg_local.set(j);
1227 _arg_stack.set(j);
1228 }
1229 j += t->size();
1230 }
1231 assert(j == _arg_size, "just checking");
1232
1233 // start with optimistic assumption
1234 ciType *rt = _method->return_type();
1235 if (rt->is_primitive_type()) {
1236 _return_local = false;
1237 _return_allocated = false;
1238 } else {
1239 _return_local = true;
1240 _return_allocated = true;
1241 }
1242 _allocated_escapes = false;
1243 _unknown_modified = false;
1244 }
1245
1246 void BCEscapeAnalyzer::clear_escape_info() {
1247 ciSignature* sig = method()->signature();
1248 int arg_count = sig->count();
1249 ArgumentMap var;
1250 if (!method()->is_static()) {
1251 arg_count++; // allow for "this"
1252 }
1253 for (int i = 0; i < arg_count; i++) {
1254 set_arg_modified(i, OFFSET_ANY, 4);
1255 var.clear();
1256 var.set(i);
1257 set_modified(var, OFFSET_ANY, 4);
1258 set_global_escape(var);
1259 }
1260 _arg_local.Clear();
1261 _arg_stack.Clear();
1262 _arg_returned.Clear();
1263 _return_local = false;
1264 _return_allocated = false;
1265 _allocated_escapes = true;
1266 _unknown_modified = true;
1267 }
1268
1269
1270 void BCEscapeAnalyzer::compute_escape_info() {
1271 int i;
1272 assert(!methodData()->has_escape_info(), "do not overwrite escape info");
1273
1274 vmIntrinsics::ID iid = known_intrinsic();
1275
1276 // check if method can be analyzed
1277 if (iid == vmIntrinsics::_none && (method()->is_abstract() || method()->is_native() || !method()->holder()->is_initialized()
1278 || _level > MaxBCEAEstimateLevel
1279 || method()->code_size() > MaxBCEAEstimateSize)) {
1280 if (BCEATraceLevel >= 1) {
1281 tty->print("Skipping method because: ");
1282 if (method()->is_abstract())
1283 tty->print_cr("method is abstract.");
1284 else if (method()->is_native())
1285 tty->print_cr("method is native.");
1286 else if (!method()->holder()->is_initialized())
1287 tty->print_cr("class of method is not initialized.");
1288 else if (_level > MaxBCEAEstimateLevel)
1289 tty->print_cr("level (%d) exceeds MaxBCEAEstimateLevel (%d).",
1290 _level, MaxBCEAEstimateLevel);
1291 else if (method()->code_size() > MaxBCEAEstimateSize)
1292 tty->print_cr("code size (%d) exceeds MaxBCEAEstimateSize.",
1293 method()->code_size(), MaxBCEAEstimateSize);
1294 else
1295 ShouldNotReachHere();
1296 }
1297 clear_escape_info();
1298
1299 return;
1300 }
1301
1302 if (BCEATraceLevel >= 1) {
1303 tty->print("[EA] estimating escape information for");
1304 if (iid != vmIntrinsics::_none)
1305 tty->print(" intrinsic");
1306 method()->print_short_name();
1307 tty->print_cr(" (%d bytes)", method()->code_size());
1308 }
1309
1310 bool success;
1311
1312 initialize();
1313
1314 // Do not scan method if it has no object parameters and
1315 // does not returns an object (_return_allocated is set in initialize()).
1316 if (_arg_local.Size() == 0 && !_return_allocated) {
1317 // Clear all info since method's bytecode was not analysed and
1318 // set pessimistic escape information.
1319 clear_escape_info();
1320 methodData()->set_eflag(MethodData::allocated_escapes);
1321 methodData()->set_eflag(MethodData::unknown_modified);
1322 methodData()->set_eflag(MethodData::estimated);
1323 return;
1324 }
1325
1326 if (iid != vmIntrinsics::_none)
1327 success = compute_escape_for_intrinsic(iid);
1328 else {
1329 success = do_analysis();
1330 }
1331
1332 // don't store interprocedural escape information if it introduces
1333 // dependencies or if method data is empty
1334 //
1335 if (!has_dependencies() && !methodData()->is_empty()) {
1336 for (i = 0; i < _arg_size; i++) {
1337 if (_arg_local.test(i)) {
1338 assert(_arg_stack.test(i), "inconsistent escape info");
1339 methodData()->set_arg_local(i);
1340 methodData()->set_arg_stack(i);
1341 } else if (_arg_stack.test(i)) {
1342 methodData()->set_arg_stack(i);
1343 }
1344 if (_arg_returned.test(i)) {
1345 methodData()->set_arg_returned(i);
1346 }
1347 methodData()->set_arg_modified(i, _arg_modified[i]);
1348 }
1349 if (_return_local) {
1350 methodData()->set_eflag(MethodData::return_local);
1351 }
1352 if (_return_allocated) {
1353 methodData()->set_eflag(MethodData::return_allocated);
1354 }
1355 if (_allocated_escapes) {
1356 methodData()->set_eflag(MethodData::allocated_escapes);
1357 }
1358 if (_unknown_modified) {
1359 methodData()->set_eflag(MethodData::unknown_modified);
1360 }
1361 methodData()->set_eflag(MethodData::estimated);
1362 }
1363 }
1364
1365 void BCEscapeAnalyzer::read_escape_info() {
1366 assert(methodData()->has_escape_info(), "no escape info available");
1367
1368 // read escape information from method descriptor
1369 for (int i = 0; i < _arg_size; i++) {
1370 if (methodData()->is_arg_local(i))
1371 _arg_local.set(i);
1372 if (methodData()->is_arg_stack(i))
1373 _arg_stack.set(i);
1374 if (methodData()->is_arg_returned(i))
1375 _arg_returned.set(i);
1376 _arg_modified[i] = methodData()->arg_modified(i);
1377 }
1378 _return_local = methodData()->eflag_set(MethodData::return_local);
1379 _return_allocated = methodData()->eflag_set(MethodData::return_allocated);
1380 _allocated_escapes = methodData()->eflag_set(MethodData::allocated_escapes);
1381 _unknown_modified = methodData()->eflag_set(MethodData::unknown_modified);
1382
1383 }
1384
1385 #ifndef PRODUCT
1386 void BCEscapeAnalyzer::dump() {
1387 tty->print("[EA] estimated escape information for");
1388 method()->print_short_name();
1389 tty->print_cr(has_dependencies() ? " (not stored)" : "");
1390 tty->print(" non-escaping args: ");
1391 _arg_local.print_on(tty);
1392 tty->print(" stack-allocatable args: ");
1393 _arg_stack.print_on(tty);
1394 if (_return_local) {
1395 tty->print(" returned args: ");
1396 _arg_returned.print_on(tty);
1397 } else if (is_return_allocated()) {
1398 tty->print_cr(" return allocated value");
1399 } else {
1400 tty->print_cr(" return non-local value");
1401 }
1402 tty->print(" modified args: ");
1403 for (int i = 0; i < _arg_size; i++) {
1404 if (_arg_modified[i] == 0)
1405 tty->print(" 0");
1406 else
1407 tty->print(" 0x%x", _arg_modified[i]);
1408 }
1409 tty->cr();
1410 tty->print(" flags: ");
1411 if (_return_allocated)
1412 tty->print(" return_allocated");
1413 if (_allocated_escapes)
1414 tty->print(" allocated_escapes");
1415 if (_unknown_modified)
1416 tty->print(" unknown_modified");
1417 tty->cr();
1418 }
1419 #endif
1420
1421 BCEscapeAnalyzer::BCEscapeAnalyzer(ciMethod* method, BCEscapeAnalyzer* parent)
1422 : _conservative(method == NULL || !EstimateArgEscape)
1423 , _arena(CURRENT_ENV->arena())
1424 , _method(method)
1425 , _methodData(method ? method->method_data() : NULL)
1426 , _arg_size(method ? method->arg_size() : 0)
1427 , _arg_local(_arena)
1428 , _arg_stack(_arena)
1429 , _arg_returned(_arena)
1430 , _dirty(_arena)
1431 , _return_local(false)
1432 , _return_allocated(false)
1433 , _allocated_escapes(false)
1434 , _unknown_modified(false)
1435 , _dependencies(_arena, 4, 0, NULL)
1436 , _parent(parent)
1437 , _level(parent == NULL ? 0 : parent->level() + 1) {
1438 if (!_conservative) {
1439 _arg_local.Clear();
1440 _arg_stack.Clear();
1441 _arg_returned.Clear();
1442 _dirty.Clear();
1443 Arena* arena = CURRENT_ENV->arena();
1444 _arg_modified = (uint *) arena->Amalloc(_arg_size * sizeof(uint));
1445 Copy::zero_to_bytes(_arg_modified, _arg_size * sizeof(uint));
1446
1447 if (methodData() == NULL)
1448 return;
1449 bool printit = _method->should_print_assembly();
1450 if (methodData()->has_escape_info()) {
1451 TRACE_BCEA(2, tty->print_cr("[EA] Reading previous results for %s.%s",
1452 method->holder()->name()->as_utf8(),
1453 method->name()->as_utf8()));
1454 read_escape_info();
1455 } else {
1456 TRACE_BCEA(2, tty->print_cr("[EA] computing results for %s.%s",
1457 method->holder()->name()->as_utf8(),
1458 method->name()->as_utf8()));
1459
1460 compute_escape_info();
1461 methodData()->update_escape_info();
1462 }
1463 #ifndef PRODUCT
1464 if (BCEATraceLevel >= 3) {
1465 // dump escape information
1466 dump();
1467 }
1468 #endif
1469 }
1470 }
1471
1472 void BCEscapeAnalyzer::copy_dependencies(Dependencies *deps) {
1473 if (ciEnv::current()->jvmti_can_hotswap_or_post_breakpoint()) {
1474 // Also record evol dependencies so redefinition of the
1475 // callee will trigger recompilation.
1476 deps->assert_evol_method(method());
1477 }
1478 for (int i = 0; i < _dependencies.length(); i+=2) {
1479 ciKlass *k = _dependencies.at(i)->as_klass();
1480 ciMethod *m = _dependencies.at(i+1)->as_method();
1481 deps->assert_unique_concrete_method(k, m);
1482 }
1483 }