1 /*
2 * Copyright (c) 2005, 2014, 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 arguments 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
int_to_bit(uint e) const58 uint int_to_bit(uint e) const {
59 if (e > MAXBIT)
60 e = MAXBIT;
61 return (1 << (e + 2));
62 }
63
64 public:
ArgumentMap()65 ArgumentMap() { _bits = 0;}
set_bits(uint bits)66 void set_bits(uint bits) { _bits = bits;}
get_bits() const67 uint get_bits() const { return _bits;}
clear()68 void clear() { _bits = 0;}
set_all()69 void set_all() { _bits = ~0u; }
is_empty() const70 bool is_empty() const { return _bits == 0; }
contains(uint var) const71 bool contains(uint var) const { return (_bits & int_to_bit(var)) != 0; }
is_singleton(uint var) const72 bool is_singleton(uint var) const { return (_bits == int_to_bit(var)); }
contains_unknown() const73 bool contains_unknown() const { return (_bits & UNKNOWN) != 0; }
contains_allocated() const74 bool contains_allocated() const { return (_bits & ALLOCATED) != 0; }
contains_vars() const75 bool contains_vars() const { return (_bits & (((1 << MAXBIT) -1) << 2)) != 0; }
set(uint var)76 void set(uint var) { _bits = int_to_bit(var); }
add(uint var)77 void add(uint var) { _bits |= int_to_bit(var); }
add_unknown()78 void add_unknown() { _bits = UNKNOWN; }
add_allocated()79 void add_allocated() { _bits = ALLOCATED; }
set_union(const ArgumentMap & am)80 void set_union(const ArgumentMap &am) { _bits |= am._bits; }
set_intersect(const ArgumentMap & am)81 void set_intersect(const ArgumentMap &am) { _bits |= am._bits; }
set_difference(const ArgumentMap & am)82 void set_difference(const ArgumentMap &am) { _bits &= ~am._bits; }
operator =(const ArgumentMap & am)83 void operator=(const ArgumentMap &am) { _bits = am._bits; }
operator ==(const ArgumentMap & am)84 bool operator==(const ArgumentMap &am) { return _bits == am._bits; }
operator !=(const ArgumentMap & am)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 int _stack_height;
93 int _max_stack;
94 bool _initialized;
95 ArgumentMap empty_map;
96
StateInfo()97 StateInfo() {
98 empty_map.clear();
99 }
100
raw_pop()101 ArgumentMap raw_pop() { guarantee(_stack_height > 0, "stack underflow"); return _stack[--_stack_height]; }
apop()102 ArgumentMap apop() { return raw_pop(); }
spop()103 void spop() { raw_pop(); }
lpop()104 void lpop() { spop(); spop(); }
raw_push(ArgumentMap i)105 void raw_push(ArgumentMap i) { guarantee(_stack_height < _max_stack, "stack overflow"); _stack[_stack_height++] = i; }
apush(ArgumentMap i)106 void apush(ArgumentMap i) { raw_push(i); }
spush()107 void spush() { raw_push(empty_map); }
lpush()108 void lpush() { spush(); spush(); }
109
110 };
111
set_returned(ArgumentMap vars)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
is_argument(ArgumentMap vars)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
is_arg_stack(ArgumentMap vars)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
returns_all(ArgumentMap vars)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
clear_bits(ArgumentMap vars,VectorSet & bm)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
set_method_escape(ArgumentMap vars)159 void BCEscapeAnalyzer::set_method_escape(ArgumentMap vars) {
160 clear_bits(vars, _arg_local);
161 if (vars.contains_allocated()) {
162 _allocated_escapes = true;
163 }
164 }
165
set_global_escape(ArgumentMap vars,bool merge)166 void BCEscapeAnalyzer::set_global_escape(ArgumentMap vars, bool merge) {
167 clear_bits(vars, _arg_local);
168 clear_bits(vars, _arg_stack);
169 if (vars.contains_allocated())
170 _allocated_escapes = true;
171
172 if (merge && !vars.is_empty()) {
173 // Merge new state into already processed block.
174 // New state is not taken into account and
175 // it may invalidate set_returned() result.
176 if (vars.contains_unknown() || vars.contains_allocated()) {
177 _return_local = false;
178 }
179 if (vars.contains_unknown() || vars.contains_vars()) {
180 _return_allocated = false;
181 }
182 if (_return_local && vars.contains_vars() && !returns_all(vars)) {
183 // Return result should be invalidated if args in new
184 // state are not recorded in return state.
185 _return_local = false;
186 }
187 }
188 }
189
set_dirty(ArgumentMap vars)190 void BCEscapeAnalyzer::set_dirty(ArgumentMap vars) {
191 clear_bits(vars, _dirty);
192 }
193
set_modified(ArgumentMap vars,int offs,int size)194 void BCEscapeAnalyzer::set_modified(ArgumentMap vars, int offs, int size) {
195
196 for (int i = 0; i < _arg_size; i++) {
197 if (vars.contains(i)) {
198 set_arg_modified(i, offs, size);
199 }
200 }
201 if (vars.contains_unknown())
202 _unknown_modified = true;
203 }
204
is_recursive_call(ciMethod * callee)205 bool BCEscapeAnalyzer::is_recursive_call(ciMethod* callee) {
206 for (BCEscapeAnalyzer* scope = this; scope != NULL; scope = scope->_parent) {
207 if (scope->method() == callee) {
208 return true;
209 }
210 }
211 return false;
212 }
213
is_arg_modified(int arg,int offset,int size_in_bytes)214 bool BCEscapeAnalyzer::is_arg_modified(int arg, int offset, int size_in_bytes) {
215 if (offset == OFFSET_ANY)
216 return _arg_modified[arg] != 0;
217 assert(arg >= 0 && arg < _arg_size, "must be an argument.");
218 bool modified = false;
219 int l = offset / HeapWordSize;
220 int h = round_to(offset + size_in_bytes, HeapWordSize) / HeapWordSize;
221 if (l > ARG_OFFSET_MAX)
222 l = ARG_OFFSET_MAX;
223 if (h > ARG_OFFSET_MAX+1)
224 h = ARG_OFFSET_MAX + 1;
225 for (int i = l; i < h; i++) {
226 modified = modified || (_arg_modified[arg] & (1 << i)) != 0;
227 }
228 return modified;
229 }
230
set_arg_modified(int arg,int offset,int size_in_bytes)231 void BCEscapeAnalyzer::set_arg_modified(int arg, int offset, int size_in_bytes) {
232 if (offset == OFFSET_ANY) {
233 _arg_modified[arg] = (uint) -1;
234 return;
235 }
236 assert(arg >= 0 && arg < _arg_size, "must be an argument.");
237 int l = offset / HeapWordSize;
238 int h = round_to(offset + size_in_bytes, HeapWordSize) / HeapWordSize;
239 if (l > ARG_OFFSET_MAX)
240 l = ARG_OFFSET_MAX;
241 if (h > ARG_OFFSET_MAX+1)
242 h = ARG_OFFSET_MAX + 1;
243 for (int i = l; i < h; i++) {
244 _arg_modified[arg] |= (1 << i);
245 }
246 }
247
invoke(StateInfo & state,Bytecodes::Code code,ciMethod * target,ciKlass * holder)248 void BCEscapeAnalyzer::invoke(StateInfo &state, Bytecodes::Code code, ciMethod* target, ciKlass* holder) {
249 int i;
250
251 // retrieve information about the callee
252 ciInstanceKlass* klass = target->holder();
253 ciInstanceKlass* calling_klass = method()->holder();
254 ciInstanceKlass* callee_holder = ciEnv::get_instance_klass_for_declared_method_holder(holder);
255 ciInstanceKlass* actual_recv = callee_holder;
256
257 // Some methods are obviously bindable without any type checks so
258 // convert them directly to an invokespecial or invokestatic.
259 if (target->is_loaded() && !target->is_abstract() && target->can_be_statically_bound()) {
260 switch (code) {
261 case Bytecodes::_invokevirtual:
262 code = Bytecodes::_invokespecial;
263 break;
264 case Bytecodes::_invokehandle:
265 code = target->is_static() ? Bytecodes::_invokestatic : Bytecodes::_invokespecial;
266 break;
267 }
268 }
269
270 // compute size of arguments
271 int arg_size = target->invoke_arg_size(code);
272 int arg_base = MAX2(state._stack_height - arg_size, 0);
273
274 // direct recursive calls are skipped if they can be bound statically without introducing
275 // dependencies and if parameters are passed at the same position as in the current method
276 // other calls are skipped if there are no unescaped arguments passed to them
277 bool directly_recursive = (method() == target) &&
278 (code != Bytecodes::_invokevirtual || target->is_final_method() || state._stack[arg_base] .is_empty());
279
280 // check if analysis of callee can safely be skipped
281 bool skip_callee = true;
282 for (i = state._stack_height - 1; i >= arg_base && skip_callee; i--) {
283 ArgumentMap arg = state._stack[i];
284 skip_callee = !is_argument(arg) || !is_arg_stack(arg) || (directly_recursive && arg.is_singleton(i - arg_base));
285 }
286 // For now we conservatively skip invokedynamic.
287 if (code == Bytecodes::_invokedynamic) {
288 skip_callee = true;
289 }
290 if (skip_callee) {
291 TRACE_BCEA(3, tty->print_cr("[EA] skipping method %s::%s", holder->name()->as_utf8(), target->name()->as_utf8()));
292 for (i = 0; i < arg_size; i++) {
293 set_method_escape(state.raw_pop());
294 }
295 _unknown_modified = true; // assume the worst since we don't analyze the called method
296 return;
297 }
298
299 // determine actual method (use CHA if necessary)
300 ciMethod* inline_target = NULL;
301 if (target->is_loaded() && klass->is_loaded()
302 && (klass->is_initialized() || klass->is_interface() && target->holder()->is_initialized())
303 && target->is_loaded()) {
304 if (code == Bytecodes::_invokestatic
305 || code == Bytecodes::_invokespecial
306 || code == Bytecodes::_invokevirtual && target->is_final_method()) {
307 inline_target = target;
308 } else {
309 inline_target = target->find_monomorphic_target(calling_klass, callee_holder, actual_recv);
310 }
311 }
312
313 if (inline_target != NULL && !is_recursive_call(inline_target)) {
314 // analyze callee
315 BCEscapeAnalyzer analyzer(inline_target, this);
316
317 // adjust escape state of actual parameters
318 bool must_record_dependencies = false;
319 for (i = arg_size - 1; i >= 0; i--) {
320 ArgumentMap arg = state.raw_pop();
321 // Check if callee arg is a caller arg or an allocated object
322 bool allocated = arg.contains_allocated();
323 if (!(is_argument(arg) || allocated))
324 continue;
325 for (int j = 0; j < _arg_size; j++) {
326 if (arg.contains(j)) {
327 _arg_modified[j] |= analyzer._arg_modified[i];
328 }
329 }
330 if (!(is_arg_stack(arg) || allocated)) {
331 // arguments have already been recognized as escaping
332 } else if (analyzer.is_arg_stack(i) && !analyzer.is_arg_returned(i)) {
333 set_method_escape(arg);
334 must_record_dependencies = true;
335 } else {
336 set_global_escape(arg);
337 }
338 }
339 _unknown_modified = _unknown_modified || analyzer.has_non_arg_side_affects();
340
341 // record dependencies if at least one parameter retained stack-allocatable
342 if (must_record_dependencies) {
343 if (code == Bytecodes::_invokeinterface || code == Bytecodes::_invokevirtual && !target->is_final_method()) {
344 _dependencies.append(actual_recv);
345 _dependencies.append(inline_target);
346 }
347 _dependencies.appendAll(analyzer.dependencies());
348 }
349 } else {
350 TRACE_BCEA(1, tty->print_cr("[EA] virtual method %s is not monomorphic.",
351 target->name()->as_utf8()));
352 // conservatively mark all actual parameters as escaping globally
353 for (i = 0; i < arg_size; i++) {
354 ArgumentMap arg = state.raw_pop();
355 if (!is_argument(arg))
356 continue;
357 set_modified(arg, OFFSET_ANY, type2size[T_INT]*HeapWordSize);
358 set_global_escape(arg);
359 }
360 _unknown_modified = true; // assume the worst since we don't know the called method
361 }
362 }
363
contains(uint arg_set1,uint arg_set2)364 bool BCEscapeAnalyzer::contains(uint arg_set1, uint arg_set2) {
365 return ((~arg_set1) | arg_set2) == 0;
366 }
367
368
iterate_one_block(ciBlock * blk,StateInfo & state,GrowableArray<ciBlock * > & successors)369 void BCEscapeAnalyzer::iterate_one_block(ciBlock *blk, StateInfo &state, GrowableArray<ciBlock *> &successors) {
370
371 blk->set_processed();
372 ciBytecodeStream s(method());
373 int limit_bci = blk->limit_bci();
374 bool fall_through = false;
375 ArgumentMap allocated_obj;
376 allocated_obj.add_allocated();
377 ArgumentMap unknown_obj;
378 unknown_obj.add_unknown();
379 ArgumentMap empty_map;
380
381 s.reset_to_bci(blk->start_bci());
382 while (s.next() != ciBytecodeStream::EOBC() && s.cur_bci() < limit_bci) {
383 fall_through = true;
384 switch (s.cur_bc()) {
385 case Bytecodes::_nop:
386 break;
387 case Bytecodes::_aconst_null:
388 state.apush(unknown_obj);
389 break;
390 case Bytecodes::_iconst_m1:
391 case Bytecodes::_iconst_0:
392 case Bytecodes::_iconst_1:
393 case Bytecodes::_iconst_2:
394 case Bytecodes::_iconst_3:
395 case Bytecodes::_iconst_4:
396 case Bytecodes::_iconst_5:
397 case Bytecodes::_fconst_0:
398 case Bytecodes::_fconst_1:
399 case Bytecodes::_fconst_2:
400 case Bytecodes::_bipush:
401 case Bytecodes::_sipush:
402 state.spush();
403 break;
404 case Bytecodes::_lconst_0:
405 case Bytecodes::_lconst_1:
406 case Bytecodes::_dconst_0:
407 case Bytecodes::_dconst_1:
408 state.lpush();
409 break;
410 case Bytecodes::_ldc:
411 case Bytecodes::_ldc_w:
412 case Bytecodes::_ldc2_w:
413 {
414 // Avoid calling get_constant() which will try to allocate
415 // unloaded constant. We need only constant's type.
416 int index = s.get_constant_pool_index();
417 constantTag tag = s.get_constant_pool_tag(index);
418 if (tag.is_long() || tag.is_double()) {
419 // Only longs and doubles use 2 stack slots.
420 state.lpush();
421 } else if (tag.basic_type() == T_OBJECT) {
422 state.apush(unknown_obj);
423 } else {
424 state.spush();
425 }
426 break;
427 }
428 case Bytecodes::_aload:
429 state.apush(state._vars[s.get_index()]);
430 break;
431 case Bytecodes::_iload:
432 case Bytecodes::_fload:
433 case Bytecodes::_iload_0:
434 case Bytecodes::_iload_1:
435 case Bytecodes::_iload_2:
436 case Bytecodes::_iload_3:
437 case Bytecodes::_fload_0:
438 case Bytecodes::_fload_1:
439 case Bytecodes::_fload_2:
440 case Bytecodes::_fload_3:
441 state.spush();
442 break;
443 case Bytecodes::_lload:
444 case Bytecodes::_dload:
445 case Bytecodes::_lload_0:
446 case Bytecodes::_lload_1:
447 case Bytecodes::_lload_2:
448 case Bytecodes::_lload_3:
449 case Bytecodes::_dload_0:
450 case Bytecodes::_dload_1:
451 case Bytecodes::_dload_2:
452 case Bytecodes::_dload_3:
453 state.lpush();
454 break;
455 case Bytecodes::_aload_0:
456 state.apush(state._vars[0]);
457 break;
458 case Bytecodes::_aload_1:
459 state.apush(state._vars[1]);
460 break;
461 case Bytecodes::_aload_2:
462 state.apush(state._vars[2]);
463 break;
464 case Bytecodes::_aload_3:
465 state.apush(state._vars[3]);
466 break;
467 case Bytecodes::_iaload:
468 case Bytecodes::_faload:
469 case Bytecodes::_baload:
470 case Bytecodes::_caload:
471 case Bytecodes::_saload:
472 state.spop();
473 set_method_escape(state.apop());
474 state.spush();
475 break;
476 case Bytecodes::_laload:
477 case Bytecodes::_daload:
478 state.spop();
479 set_method_escape(state.apop());
480 state.lpush();
481 break;
482 case Bytecodes::_aaload:
483 { state.spop();
484 ArgumentMap array = state.apop();
485 set_method_escape(array);
486 state.apush(unknown_obj);
487 set_dirty(array);
488 }
489 break;
490 case Bytecodes::_istore:
491 case Bytecodes::_fstore:
492 case Bytecodes::_istore_0:
493 case Bytecodes::_istore_1:
494 case Bytecodes::_istore_2:
495 case Bytecodes::_istore_3:
496 case Bytecodes::_fstore_0:
497 case Bytecodes::_fstore_1:
498 case Bytecodes::_fstore_2:
499 case Bytecodes::_fstore_3:
500 state.spop();
501 break;
502 case Bytecodes::_lstore:
503 case Bytecodes::_dstore:
504 case Bytecodes::_lstore_0:
505 case Bytecodes::_lstore_1:
506 case Bytecodes::_lstore_2:
507 case Bytecodes::_lstore_3:
508 case Bytecodes::_dstore_0:
509 case Bytecodes::_dstore_1:
510 case Bytecodes::_dstore_2:
511 case Bytecodes::_dstore_3:
512 state.lpop();
513 break;
514 case Bytecodes::_astore:
515 state._vars[s.get_index()] = state.apop();
516 break;
517 case Bytecodes::_astore_0:
518 state._vars[0] = state.apop();
519 break;
520 case Bytecodes::_astore_1:
521 state._vars[1] = state.apop();
522 break;
523 case Bytecodes::_astore_2:
524 state._vars[2] = state.apop();
525 break;
526 case Bytecodes::_astore_3:
527 state._vars[3] = state.apop();
528 break;
529 case Bytecodes::_iastore:
530 case Bytecodes::_fastore:
531 case Bytecodes::_bastore:
532 case Bytecodes::_castore:
533 case Bytecodes::_sastore:
534 {
535 state.spop();
536 state.spop();
537 ArgumentMap arr = state.apop();
538 set_method_escape(arr);
539 set_modified(arr, OFFSET_ANY, type2size[T_INT]*HeapWordSize);
540 break;
541 }
542 case Bytecodes::_lastore:
543 case Bytecodes::_dastore:
544 {
545 state.lpop();
546 state.spop();
547 ArgumentMap arr = state.apop();
548 set_method_escape(arr);
549 set_modified(arr, OFFSET_ANY, type2size[T_LONG]*HeapWordSize);
550 break;
551 }
552 case Bytecodes::_aastore:
553 {
554 set_global_escape(state.apop());
555 state.spop();
556 ArgumentMap arr = state.apop();
557 set_modified(arr, OFFSET_ANY, type2size[T_OBJECT]*HeapWordSize);
558 break;
559 }
560 case Bytecodes::_pop:
561 state.raw_pop();
562 break;
563 case Bytecodes::_pop2:
564 state.raw_pop();
565 state.raw_pop();
566 break;
567 case Bytecodes::_dup:
568 { ArgumentMap w1 = state.raw_pop();
569 state.raw_push(w1);
570 state.raw_push(w1);
571 }
572 break;
573 case Bytecodes::_dup_x1:
574 { ArgumentMap w1 = state.raw_pop();
575 ArgumentMap w2 = state.raw_pop();
576 state.raw_push(w1);
577 state.raw_push(w2);
578 state.raw_push(w1);
579 }
580 break;
581 case Bytecodes::_dup_x2:
582 { ArgumentMap w1 = state.raw_pop();
583 ArgumentMap w2 = state.raw_pop();
584 ArgumentMap w3 = state.raw_pop();
585 state.raw_push(w1);
586 state.raw_push(w3);
587 state.raw_push(w2);
588 state.raw_push(w1);
589 }
590 break;
591 case Bytecodes::_dup2:
592 { ArgumentMap w1 = state.raw_pop();
593 ArgumentMap w2 = state.raw_pop();
594 state.raw_push(w2);
595 state.raw_push(w1);
596 state.raw_push(w2);
597 state.raw_push(w1);
598 }
599 break;
600 case Bytecodes::_dup2_x1:
601 { ArgumentMap w1 = state.raw_pop();
602 ArgumentMap w2 = state.raw_pop();
603 ArgumentMap w3 = state.raw_pop();
604 state.raw_push(w2);
605 state.raw_push(w1);
606 state.raw_push(w3);
607 state.raw_push(w2);
608 state.raw_push(w1);
609 }
610 break;
611 case Bytecodes::_dup2_x2:
612 { ArgumentMap w1 = state.raw_pop();
613 ArgumentMap w2 = state.raw_pop();
614 ArgumentMap w3 = state.raw_pop();
615 ArgumentMap w4 = state.raw_pop();
616 state.raw_push(w2);
617 state.raw_push(w1);
618 state.raw_push(w4);
619 state.raw_push(w3);
620 state.raw_push(w2);
621 state.raw_push(w1);
622 }
623 break;
624 case Bytecodes::_swap:
625 { ArgumentMap w1 = state.raw_pop();
626 ArgumentMap w2 = state.raw_pop();
627 state.raw_push(w1);
628 state.raw_push(w2);
629 }
630 break;
631 case Bytecodes::_iadd:
632 case Bytecodes::_fadd:
633 case Bytecodes::_isub:
634 case Bytecodes::_fsub:
635 case Bytecodes::_imul:
636 case Bytecodes::_fmul:
637 case Bytecodes::_idiv:
638 case Bytecodes::_fdiv:
639 case Bytecodes::_irem:
640 case Bytecodes::_frem:
641 case Bytecodes::_iand:
642 case Bytecodes::_ior:
643 case Bytecodes::_ixor:
644 state.spop();
645 state.spop();
646 state.spush();
647 break;
648 case Bytecodes::_ladd:
649 case Bytecodes::_dadd:
650 case Bytecodes::_lsub:
651 case Bytecodes::_dsub:
652 case Bytecodes::_lmul:
653 case Bytecodes::_dmul:
654 case Bytecodes::_ldiv:
655 case Bytecodes::_ddiv:
656 case Bytecodes::_lrem:
657 case Bytecodes::_drem:
658 case Bytecodes::_land:
659 case Bytecodes::_lor:
660 case Bytecodes::_lxor:
661 state.lpop();
662 state.lpop();
663 state.lpush();
664 break;
665 case Bytecodes::_ishl:
666 case Bytecodes::_ishr:
667 case Bytecodes::_iushr:
668 state.spop();
669 state.spop();
670 state.spush();
671 break;
672 case Bytecodes::_lshl:
673 case Bytecodes::_lshr:
674 case Bytecodes::_lushr:
675 state.spop();
676 state.lpop();
677 state.lpush();
678 break;
679 case Bytecodes::_ineg:
680 case Bytecodes::_fneg:
681 state.spop();
682 state.spush();
683 break;
684 case Bytecodes::_lneg:
685 case Bytecodes::_dneg:
686 state.lpop();
687 state.lpush();
688 break;
689 case Bytecodes::_iinc:
690 break;
691 case Bytecodes::_i2l:
692 case Bytecodes::_i2d:
693 case Bytecodes::_f2l:
694 case Bytecodes::_f2d:
695 state.spop();
696 state.lpush();
697 break;
698 case Bytecodes::_i2f:
699 case Bytecodes::_f2i:
700 state.spop();
701 state.spush();
702 break;
703 case Bytecodes::_l2i:
704 case Bytecodes::_l2f:
705 case Bytecodes::_d2i:
706 case Bytecodes::_d2f:
707 state.lpop();
708 state.spush();
709 break;
710 case Bytecodes::_l2d:
711 case Bytecodes::_d2l:
712 state.lpop();
713 state.lpush();
714 break;
715 case Bytecodes::_i2b:
716 case Bytecodes::_i2c:
717 case Bytecodes::_i2s:
718 state.spop();
719 state.spush();
720 break;
721 case Bytecodes::_lcmp:
722 case Bytecodes::_dcmpl:
723 case Bytecodes::_dcmpg:
724 state.lpop();
725 state.lpop();
726 state.spush();
727 break;
728 case Bytecodes::_fcmpl:
729 case Bytecodes::_fcmpg:
730 state.spop();
731 state.spop();
732 state.spush();
733 break;
734 case Bytecodes::_ifeq:
735 case Bytecodes::_ifne:
736 case Bytecodes::_iflt:
737 case Bytecodes::_ifge:
738 case Bytecodes::_ifgt:
739 case Bytecodes::_ifle:
740 {
741 state.spop();
742 int dest_bci = s.get_dest();
743 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
744 assert(s.next_bci() == limit_bci, "branch must end block");
745 successors.push(_methodBlocks->block_containing(dest_bci));
746 break;
747 }
748 case Bytecodes::_if_icmpeq:
749 case Bytecodes::_if_icmpne:
750 case Bytecodes::_if_icmplt:
751 case Bytecodes::_if_icmpge:
752 case Bytecodes::_if_icmpgt:
753 case Bytecodes::_if_icmple:
754 {
755 state.spop();
756 state.spop();
757 int dest_bci = s.get_dest();
758 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
759 assert(s.next_bci() == limit_bci, "branch must end block");
760 successors.push(_methodBlocks->block_containing(dest_bci));
761 break;
762 }
763 case Bytecodes::_if_acmpeq:
764 case Bytecodes::_if_acmpne:
765 {
766 set_method_escape(state.apop());
767 set_method_escape(state.apop());
768 int dest_bci = s.get_dest();
769 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
770 assert(s.next_bci() == limit_bci, "branch must end block");
771 successors.push(_methodBlocks->block_containing(dest_bci));
772 break;
773 }
774 case Bytecodes::_goto:
775 {
776 int dest_bci = s.get_dest();
777 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
778 assert(s.next_bci() == limit_bci, "branch must end block");
779 successors.push(_methodBlocks->block_containing(dest_bci));
780 fall_through = false;
781 break;
782 }
783 case Bytecodes::_jsr:
784 {
785 int dest_bci = s.get_dest();
786 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
787 assert(s.next_bci() == limit_bci, "branch must end block");
788 state.apush(empty_map);
789 successors.push(_methodBlocks->block_containing(dest_bci));
790 fall_through = false;
791 break;
792 }
793 case Bytecodes::_ret:
794 // we don't track the destination of a "ret" instruction
795 assert(s.next_bci() == limit_bci, "branch must end block");
796 fall_through = false;
797 break;
798 case Bytecodes::_return:
799 assert(s.next_bci() == limit_bci, "return must end block");
800 fall_through = false;
801 break;
802 case Bytecodes::_tableswitch:
803 {
804 state.spop();
805 Bytecode_tableswitch sw(&s);
806 int len = sw.length();
807 int dest_bci;
808 for (int i = 0; i < len; i++) {
809 dest_bci = s.cur_bci() + sw.dest_offset_at(i);
810 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
811 successors.push(_methodBlocks->block_containing(dest_bci));
812 }
813 dest_bci = s.cur_bci() + sw.default_offset();
814 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
815 successors.push(_methodBlocks->block_containing(dest_bci));
816 assert(s.next_bci() == limit_bci, "branch must end block");
817 fall_through = false;
818 break;
819 }
820 case Bytecodes::_lookupswitch:
821 {
822 state.spop();
823 Bytecode_lookupswitch sw(&s);
824 int len = sw.number_of_pairs();
825 int dest_bci;
826 for (int i = 0; i < len; i++) {
827 dest_bci = s.cur_bci() + sw.pair_at(i).offset();
828 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
829 successors.push(_methodBlocks->block_containing(dest_bci));
830 }
831 dest_bci = s.cur_bci() + sw.default_offset();
832 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
833 successors.push(_methodBlocks->block_containing(dest_bci));
834 fall_through = false;
835 break;
836 }
837 case Bytecodes::_ireturn:
838 case Bytecodes::_freturn:
839 state.spop();
840 fall_through = false;
841 break;
842 case Bytecodes::_lreturn:
843 case Bytecodes::_dreturn:
844 state.lpop();
845 fall_through = false;
846 break;
847 case Bytecodes::_areturn:
848 set_returned(state.apop());
849 fall_through = false;
850 break;
851 case Bytecodes::_getstatic:
852 case Bytecodes::_getfield:
853 { bool ignored_will_link;
854 ciField* field = s.get_field(ignored_will_link);
855 BasicType field_type = field->type()->basic_type();
856 if (s.cur_bc() != Bytecodes::_getstatic) {
857 set_method_escape(state.apop());
858 }
859 if (field_type == T_OBJECT || field_type == T_ARRAY) {
860 state.apush(unknown_obj);
861 } else if (type2size[field_type] == 1) {
862 state.spush();
863 } else {
864 state.lpush();
865 }
866 }
867 break;
868 case Bytecodes::_putstatic:
869 case Bytecodes::_putfield:
870 { bool will_link;
871 ciField* field = s.get_field(will_link);
872 BasicType field_type = field->type()->basic_type();
873 if (field_type == T_OBJECT || field_type == T_ARRAY) {
874 set_global_escape(state.apop());
875 } else if (type2size[field_type] == 1) {
876 state.spop();
877 } else {
878 state.lpop();
879 }
880 if (s.cur_bc() != Bytecodes::_putstatic) {
881 ArgumentMap p = state.apop();
882 set_method_escape(p);
883 set_modified(p, will_link ? field->offset() : OFFSET_ANY, type2size[field_type]*HeapWordSize);
884 }
885 }
886 break;
887 case Bytecodes::_invokevirtual:
888 case Bytecodes::_invokespecial:
889 case Bytecodes::_invokestatic:
890 case Bytecodes::_invokedynamic:
891 case Bytecodes::_invokeinterface:
892 { bool ignored_will_link;
893 ciSignature* declared_signature = NULL;
894 ciMethod* target = s.get_method(ignored_will_link, &declared_signature);
895 ciKlass* holder = s.get_declared_method_holder();
896 assert(declared_signature != NULL, "cannot be null");
897 // Push appendix argument, if one.
898 if (s.has_appendix()) {
899 state.apush(unknown_obj);
900 }
901 // Pass in raw bytecode because we need to see invokehandle instructions.
902 invoke(state, s.cur_bc_raw(), target, holder);
903 // We are using the return type of the declared signature here because
904 // it might be a more concrete type than the one from the target (for
905 // e.g. invokedynamic and invokehandle).
906 ciType* return_type = declared_signature->return_type();
907 if (!return_type->is_primitive_type()) {
908 state.apush(unknown_obj);
909 } else if (return_type->is_one_word()) {
910 state.spush();
911 } else if (return_type->is_two_word()) {
912 state.lpush();
913 }
914 }
915 break;
916 case Bytecodes::_new:
917 state.apush(allocated_obj);
918 break;
919 case Bytecodes::_newarray:
920 case Bytecodes::_anewarray:
921 state.spop();
922 state.apush(allocated_obj);
923 break;
924 case Bytecodes::_multianewarray:
925 { int i = s.cur_bcp()[3];
926 while (i-- > 0) state.spop();
927 state.apush(allocated_obj);
928 }
929 break;
930 case Bytecodes::_arraylength:
931 set_method_escape(state.apop());
932 state.spush();
933 break;
934 case Bytecodes::_athrow:
935 set_global_escape(state.apop());
936 fall_through = false;
937 break;
938 case Bytecodes::_checkcast:
939 { ArgumentMap obj = state.apop();
940 set_method_escape(obj);
941 state.apush(obj);
942 }
943 break;
944 case Bytecodes::_instanceof:
945 set_method_escape(state.apop());
946 state.spush();
947 break;
948 case Bytecodes::_monitorenter:
949 case Bytecodes::_monitorexit:
950 state.apop();
951 break;
952 case Bytecodes::_wide:
953 ShouldNotReachHere();
954 break;
955 case Bytecodes::_ifnull:
956 case Bytecodes::_ifnonnull:
957 {
958 set_method_escape(state.apop());
959 int dest_bci = s.get_dest();
960 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
961 assert(s.next_bci() == limit_bci, "branch must end block");
962 successors.push(_methodBlocks->block_containing(dest_bci));
963 break;
964 }
965 case Bytecodes::_goto_w:
966 {
967 int dest_bci = s.get_far_dest();
968 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
969 assert(s.next_bci() == limit_bci, "branch must end block");
970 successors.push(_methodBlocks->block_containing(dest_bci));
971 fall_through = false;
972 break;
973 }
974 case Bytecodes::_jsr_w:
975 {
976 int dest_bci = s.get_far_dest();
977 assert(_methodBlocks->is_block_start(dest_bci), "branch destination must start a block");
978 assert(s.next_bci() == limit_bci, "branch must end block");
979 state.apush(empty_map);
980 successors.push(_methodBlocks->block_containing(dest_bci));
981 fall_through = false;
982 break;
983 }
984 case Bytecodes::_breakpoint:
985 break;
986 default:
987 ShouldNotReachHere();
988 break;
989 }
990
991 }
992 if (fall_through) {
993 int fall_through_bci = s.cur_bci();
994 if (fall_through_bci < _method->code_size()) {
995 assert(_methodBlocks->is_block_start(fall_through_bci), "must fall through to block start.");
996 successors.push(_methodBlocks->block_containing(fall_through_bci));
997 }
998 }
999 }
1000
merge_block_states(StateInfo * blockstates,ciBlock * dest,StateInfo * s_state)1001 void BCEscapeAnalyzer::merge_block_states(StateInfo *blockstates, ciBlock *dest, StateInfo *s_state) {
1002 StateInfo *d_state = blockstates + dest->index();
1003 int nlocals = _method->max_locals();
1004
1005 // exceptions may cause transfer of control to handlers in the middle of a
1006 // block, so we don't merge the incoming state of exception handlers
1007 if (dest->is_handler())
1008 return;
1009 if (!d_state->_initialized ) {
1010 // destination not initialized, just copy
1011 for (int i = 0; i < nlocals; i++) {
1012 d_state->_vars[i] = s_state->_vars[i];
1013 }
1014 for (int i = 0; i < s_state->_stack_height; i++) {
1015 d_state->_stack[i] = s_state->_stack[i];
1016 }
1017 d_state->_stack_height = s_state->_stack_height;
1018 d_state->_max_stack = s_state->_max_stack;
1019 d_state->_initialized = true;
1020 } else if (!dest->processed()) {
1021 // we have not yet walked the bytecodes of dest, we can merge
1022 // the states
1023 assert(d_state->_stack_height == s_state->_stack_height, "computed stack heights must match");
1024 for (int i = 0; i < nlocals; i++) {
1025 d_state->_vars[i].set_union(s_state->_vars[i]);
1026 }
1027 for (int i = 0; i < s_state->_stack_height; i++) {
1028 d_state->_stack[i].set_union(s_state->_stack[i]);
1029 }
1030 } else {
1031 // the bytecodes of dest have already been processed, mark any
1032 // arguments in the source state which are not in the dest state
1033 // as global escape.
1034 // Future refinement: we only need to mark these variable to the
1035 // maximum escape of any variables in dest state
1036 assert(d_state->_stack_height == s_state->_stack_height, "computed stack heights must match");
1037 ArgumentMap extra_vars;
1038 for (int i = 0; i < nlocals; i++) {
1039 ArgumentMap t;
1040 t = s_state->_vars[i];
1041 t.set_difference(d_state->_vars[i]);
1042 extra_vars.set_union(t);
1043 }
1044 for (int i = 0; i < s_state->_stack_height; i++) {
1045 ArgumentMap t;
1046 //extra_vars |= !d_state->_vars[i] & s_state->_vars[i];
1047 t.clear();
1048 t = s_state->_stack[i];
1049 t.set_difference(d_state->_stack[i]);
1050 extra_vars.set_union(t);
1051 }
1052 set_global_escape(extra_vars, true);
1053 }
1054 }
1055
iterate_blocks(Arena * arena)1056 void BCEscapeAnalyzer::iterate_blocks(Arena *arena) {
1057 int numblocks = _methodBlocks->num_blocks();
1058 int stkSize = _method->max_stack();
1059 int numLocals = _method->max_locals();
1060 StateInfo state;
1061
1062 int datacount = (numblocks + 1) * (stkSize + numLocals);
1063 int datasize = datacount * sizeof(ArgumentMap);
1064 StateInfo *blockstates = (StateInfo *) arena->Amalloc(numblocks * sizeof(StateInfo));
1065 ArgumentMap *statedata = (ArgumentMap *) arena->Amalloc(datasize);
1066 for (int i = 0; i < datacount; i++) ::new ((void*)&statedata[i]) ArgumentMap();
1067 ArgumentMap *dp = statedata;
1068 state._vars = dp;
1069 dp += numLocals;
1070 state._stack = dp;
1071 dp += stkSize;
1072 state._initialized = false;
1073 state._max_stack = stkSize;
1074 for (int i = 0; i < numblocks; i++) {
1075 blockstates[i]._vars = dp;
1076 dp += numLocals;
1077 blockstates[i]._stack = dp;
1078 dp += stkSize;
1079 blockstates[i]._initialized = false;
1080 blockstates[i]._stack_height = 0;
1081 blockstates[i]._max_stack = stkSize;
1082 }
1083 GrowableArray<ciBlock *> worklist(arena, numblocks / 4, 0, NULL);
1084 GrowableArray<ciBlock *> successors(arena, 4, 0, NULL);
1085
1086 _methodBlocks->clear_processed();
1087
1088 // initialize block 0 state from method signature
1089 ArgumentMap allVars; // all oop arguments to method
1090 ciSignature* sig = method()->signature();
1091 int j = 0;
1092 ciBlock* first_blk = _methodBlocks->block_containing(0);
1093 int fb_i = first_blk->index();
1094 if (!method()->is_static()) {
1095 // record information for "this"
1096 blockstates[fb_i]._vars[j].set(j);
1097 allVars.add(j);
1098 j++;
1099 }
1100 for (int i = 0; i < sig->count(); i++) {
1101 ciType* t = sig->type_at(i);
1102 if (!t->is_primitive_type()) {
1103 blockstates[fb_i]._vars[j].set(j);
1104 allVars.add(j);
1105 }
1106 j += t->size();
1107 }
1108 blockstates[fb_i]._initialized = true;
1109 assert(j == _arg_size, "just checking");
1110
1111 ArgumentMap unknown_map;
1112 unknown_map.add_unknown();
1113
1114 worklist.push(first_blk);
1115 while(worklist.length() > 0) {
1116 ciBlock *blk = worklist.pop();
1117 StateInfo *blkState = blockstates + blk->index();
1118 if (blk->is_handler() || blk->is_ret_target()) {
1119 // for an exception handler or a target of a ret instruction, we assume the worst case,
1120 // that any variable could contain any argument
1121 for (int i = 0; i < numLocals; i++) {
1122 state._vars[i] = allVars;
1123 }
1124 if (blk->is_handler()) {
1125 state._stack_height = 1;
1126 } else {
1127 state._stack_height = blkState->_stack_height;
1128 }
1129 for (int i = 0; i < state._stack_height; i++) {
1130 // ??? should this be unknown_map ???
1131 state._stack[i] = allVars;
1132 }
1133 } else {
1134 for (int i = 0; i < numLocals; i++) {
1135 state._vars[i] = blkState->_vars[i];
1136 }
1137 for (int i = 0; i < blkState->_stack_height; i++) {
1138 state._stack[i] = blkState->_stack[i];
1139 }
1140 state._stack_height = blkState->_stack_height;
1141 }
1142 iterate_one_block(blk, state, successors);
1143 // if this block has any exception handlers, push them
1144 // onto successor list
1145 if (blk->has_handler()) {
1146 DEBUG_ONLY(int handler_count = 0;)
1147 int blk_start = blk->start_bci();
1148 int blk_end = blk->limit_bci();
1149 for (int i = 0; i < numblocks; i++) {
1150 ciBlock *b = _methodBlocks->block(i);
1151 if (b->is_handler()) {
1152 int ex_start = b->ex_start_bci();
1153 int ex_end = b->ex_limit_bci();
1154 if ((ex_start >= blk_start && ex_start < blk_end) ||
1155 (ex_end > blk_start && ex_end <= blk_end)) {
1156 successors.push(b);
1157 }
1158 DEBUG_ONLY(handler_count++;)
1159 }
1160 }
1161 assert(handler_count > 0, "must find at least one handler");
1162 }
1163 // merge computed variable state with successors
1164 while(successors.length() > 0) {
1165 ciBlock *succ = successors.pop();
1166 merge_block_states(blockstates, succ, &state);
1167 if (!succ->processed())
1168 worklist.push(succ);
1169 }
1170 }
1171 }
1172
do_analysis()1173 void BCEscapeAnalyzer::do_analysis() {
1174 Arena* arena = CURRENT_ENV->arena();
1175 // identify basic blocks
1176 _methodBlocks = _method->get_method_blocks();
1177
1178 iterate_blocks(arena);
1179 }
1180
known_intrinsic()1181 vmIntrinsics::ID BCEscapeAnalyzer::known_intrinsic() {
1182 vmIntrinsics::ID iid = method()->intrinsic_id();
1183 if (iid == vmIntrinsics::_getClass ||
1184 iid == vmIntrinsics::_fillInStackTrace ||
1185 iid == vmIntrinsics::_hashCode) {
1186 return iid;
1187 } else {
1188 return vmIntrinsics::_none;
1189 }
1190 }
1191
compute_escape_for_intrinsic(vmIntrinsics::ID iid)1192 void BCEscapeAnalyzer::compute_escape_for_intrinsic(vmIntrinsics::ID iid) {
1193 ArgumentMap arg;
1194 arg.clear();
1195 switch (iid) {
1196 case vmIntrinsics::_getClass:
1197 _return_local = false;
1198 _return_allocated = false;
1199 break;
1200 case vmIntrinsics::_fillInStackTrace:
1201 arg.set(0); // 'this'
1202 set_returned(arg);
1203 break;
1204 case vmIntrinsics::_hashCode:
1205 // initialized state is correct
1206 break;
1207 default:
1208 assert(false, "unexpected intrinsic");
1209 }
1210 }
1211
initialize()1212 void BCEscapeAnalyzer::initialize() {
1213 int i;
1214
1215 // clear escape information (method may have been deoptimized)
1216 methodData()->clear_escape_info();
1217
1218 // initialize escape state of object parameters
1219 ciSignature* sig = method()->signature();
1220 int j = 0;
1221 if (!method()->is_static()) {
1222 _arg_local.set(0);
1223 _arg_stack.set(0);
1224 j++;
1225 }
1226 for (i = 0; i < sig->count(); i++) {
1227 ciType* t = sig->type_at(i);
1228 if (!t->is_primitive_type()) {
1229 _arg_local.set(j);
1230 _arg_stack.set(j);
1231 }
1232 j += t->size();
1233 }
1234 assert(j == _arg_size, "just checking");
1235
1236 // start with optimistic assumption
1237 ciType *rt = _method->return_type();
1238 if (rt->is_primitive_type()) {
1239 _return_local = false;
1240 _return_allocated = false;
1241 } else {
1242 _return_local = true;
1243 _return_allocated = true;
1244 }
1245 _allocated_escapes = false;
1246 _unknown_modified = false;
1247 }
1248
clear_escape_info()1249 void BCEscapeAnalyzer::clear_escape_info() {
1250 ciSignature* sig = method()->signature();
1251 int arg_count = sig->count();
1252 ArgumentMap var;
1253 if (!method()->is_static()) {
1254 arg_count++; // allow for "this"
1255 }
1256 for (int i = 0; i < arg_count; i++) {
1257 set_arg_modified(i, OFFSET_ANY, 4);
1258 var.clear();
1259 var.set(i);
1260 set_modified(var, OFFSET_ANY, 4);
1261 set_global_escape(var);
1262 }
1263 _arg_local.Clear();
1264 _arg_stack.Clear();
1265 _arg_returned.Clear();
1266 _return_local = false;
1267 _return_allocated = false;
1268 _allocated_escapes = true;
1269 _unknown_modified = true;
1270 }
1271
1272
compute_escape_info()1273 void BCEscapeAnalyzer::compute_escape_info() {
1274 int i;
1275 assert(!methodData()->has_escape_info(), "do not overwrite escape info");
1276
1277 vmIntrinsics::ID iid = known_intrinsic();
1278
1279 // check if method can be analyzed
1280 if (iid == vmIntrinsics::_none && (method()->is_abstract() || method()->is_native() || !method()->holder()->is_initialized()
1281 || _level > MaxBCEAEstimateLevel
1282 || method()->code_size() > MaxBCEAEstimateSize)) {
1283 if (BCEATraceLevel >= 1) {
1284 tty->print("Skipping method because: ");
1285 if (method()->is_abstract())
1286 tty->print_cr("method is abstract.");
1287 else if (method()->is_native())
1288 tty->print_cr("method is native.");
1289 else if (!method()->holder()->is_initialized())
1290 tty->print_cr("class of method is not initialized.");
1291 else if (_level > MaxBCEAEstimateLevel)
1292 tty->print_cr("level (%d) exceeds MaxBCEAEstimateLevel (%d).",
1293 _level, (int) MaxBCEAEstimateLevel);
1294 else if (method()->code_size() > MaxBCEAEstimateSize)
1295 tty->print_cr("code size (%d) exceeds MaxBCEAEstimateSize (%d).",
1296 method()->code_size(), (int) MaxBCEAEstimateSize);
1297 else
1298 ShouldNotReachHere();
1299 }
1300 clear_escape_info();
1301
1302 return;
1303 }
1304
1305 if (BCEATraceLevel >= 1) {
1306 tty->print("[EA] estimating escape information for");
1307 if (iid != vmIntrinsics::_none)
1308 tty->print(" intrinsic");
1309 method()->print_short_name();
1310 tty->print_cr(" (%d bytes)", method()->code_size());
1311 }
1312
1313 initialize();
1314
1315 // Do not scan method if it has no object parameters and
1316 // does not returns an object (_return_allocated is set in initialize()).
1317 if (_arg_local.Size() == 0 && !_return_allocated) {
1318 // Clear all info since method's bytecode was not analysed and
1319 // set pessimistic escape information.
1320 clear_escape_info();
1321 methodData()->set_eflag(MethodData::allocated_escapes);
1322 methodData()->set_eflag(MethodData::unknown_modified);
1323 methodData()->set_eflag(MethodData::estimated);
1324 return;
1325 }
1326
1327 if (iid != vmIntrinsics::_none)
1328 compute_escape_for_intrinsic(iid);
1329 else {
1330 do_analysis();
1331 }
1332
1333 // don't store interprocedural escape information if it introduces
1334 // dependencies or if method data is empty
1335 //
1336 if (!has_dependencies() && !methodData()->is_empty()) {
1337 for (i = 0; i < _arg_size; i++) {
1338 if (_arg_local.test(i)) {
1339 assert(_arg_stack.test(i), "inconsistent escape info");
1340 methodData()->set_arg_local(i);
1341 methodData()->set_arg_stack(i);
1342 } else if (_arg_stack.test(i)) {
1343 methodData()->set_arg_stack(i);
1344 }
1345 if (_arg_returned.test(i)) {
1346 methodData()->set_arg_returned(i);
1347 }
1348 methodData()->set_arg_modified(i, _arg_modified[i]);
1349 }
1350 if (_return_local) {
1351 methodData()->set_eflag(MethodData::return_local);
1352 }
1353 if (_return_allocated) {
1354 methodData()->set_eflag(MethodData::return_allocated);
1355 }
1356 if (_allocated_escapes) {
1357 methodData()->set_eflag(MethodData::allocated_escapes);
1358 }
1359 if (_unknown_modified) {
1360 methodData()->set_eflag(MethodData::unknown_modified);
1361 }
1362 methodData()->set_eflag(MethodData::estimated);
1363 }
1364 }
1365
read_escape_info()1366 void BCEscapeAnalyzer::read_escape_info() {
1367 assert(methodData()->has_escape_info(), "no escape info available");
1368
1369 // read escape information from method descriptor
1370 for (int i = 0; i < _arg_size; i++) {
1371 if (methodData()->is_arg_local(i))
1372 _arg_local.set(i);
1373 if (methodData()->is_arg_stack(i))
1374 _arg_stack.set(i);
1375 if (methodData()->is_arg_returned(i))
1376 _arg_returned.set(i);
1377 _arg_modified[i] = methodData()->arg_modified(i);
1378 }
1379 _return_local = methodData()->eflag_set(MethodData::return_local);
1380 _return_allocated = methodData()->eflag_set(MethodData::return_allocated);
1381 _allocated_escapes = methodData()->eflag_set(MethodData::allocated_escapes);
1382 _unknown_modified = methodData()->eflag_set(MethodData::unknown_modified);
1383
1384 }
1385
1386 #ifndef PRODUCT
dump()1387 void BCEscapeAnalyzer::dump() {
1388 tty->print("[EA] estimated escape information for");
1389 method()->print_short_name();
1390 tty->print_cr(has_dependencies() ? " (not stored)" : "");
1391 tty->print(" non-escaping args: ");
1392 _arg_local.print_on(tty);
1393 tty->print(" stack-allocatable args: ");
1394 _arg_stack.print_on(tty);
1395 if (_return_local) {
1396 tty->print(" returned args: ");
1397 _arg_returned.print_on(tty);
1398 } else if (is_return_allocated()) {
1399 tty->print_cr(" return allocated value");
1400 } else {
1401 tty->print_cr(" return non-local value");
1402 }
1403 tty->print(" modified args: ");
1404 for (int i = 0; i < _arg_size; i++) {
1405 if (_arg_modified[i] == 0)
1406 tty->print(" 0");
1407 else
1408 tty->print(" 0x%x", _arg_modified[i]);
1409 }
1410 tty->cr();
1411 tty->print(" flags: ");
1412 if (_return_allocated)
1413 tty->print(" return_allocated");
1414 if (_allocated_escapes)
1415 tty->print(" allocated_escapes");
1416 if (_unknown_modified)
1417 tty->print(" unknown_modified");
1418 tty->cr();
1419 }
1420 #endif
1421
BCEscapeAnalyzer(ciMethod * method,BCEscapeAnalyzer * parent)1422 BCEscapeAnalyzer::BCEscapeAnalyzer(ciMethod* method, BCEscapeAnalyzer* parent)
1423 : _conservative(method == NULL || !EstimateArgEscape)
1424 , _arena(CURRENT_ENV->arena())
1425 , _method(method)
1426 , _methodData(method ? method->method_data() : NULL)
1427 , _arg_size(method ? method->arg_size() : 0)
1428 , _arg_local(_arena)
1429 , _arg_stack(_arena)
1430 , _arg_returned(_arena)
1431 , _dirty(_arena)
1432 , _return_local(false)
1433 , _return_allocated(false)
1434 , _allocated_escapes(false)
1435 , _unknown_modified(false)
1436 , _dependencies(_arena, 4, 0, NULL)
1437 , _parent(parent)
1438 , _level(parent == NULL ? 0 : parent->level() + 1) {
1439 if (!_conservative) {
1440 _arg_local.Clear();
1441 _arg_stack.Clear();
1442 _arg_returned.Clear();
1443 _dirty.Clear();
1444 Arena* arena = CURRENT_ENV->arena();
1445 _arg_modified = (uint *) arena->Amalloc(_arg_size * sizeof(uint));
1446 Copy::zero_to_bytes(_arg_modified, _arg_size * sizeof(uint));
1447
1448 if (methodData() == NULL)
1449 return;
1450 bool printit = _method->should_print_assembly();
1451 if (methodData()->has_escape_info()) {
1452 TRACE_BCEA(2, tty->print_cr("[EA] Reading previous results for %s.%s",
1453 method->holder()->name()->as_utf8(),
1454 method->name()->as_utf8()));
1455 read_escape_info();
1456 } else {
1457 TRACE_BCEA(2, tty->print_cr("[EA] computing results for %s.%s",
1458 method->holder()->name()->as_utf8(),
1459 method->name()->as_utf8()));
1460
1461 compute_escape_info();
1462 methodData()->update_escape_info();
1463 }
1464 #ifndef PRODUCT
1465 if (BCEATraceLevel >= 3) {
1466 // dump escape information
1467 dump();
1468 }
1469 #endif
1470 }
1471 }
1472
copy_dependencies(Dependencies * deps)1473 void BCEscapeAnalyzer::copy_dependencies(Dependencies *deps) {
1474 if (ciEnv::current()->jvmti_can_hotswap_or_post_breakpoint()) {
1475 // Also record evol dependencies so redefinition of the
1476 // callee will trigger recompilation.
1477 deps->assert_evol_method(method());
1478 }
1479 for (int i = 0; i < _dependencies.length(); i+=2) {
1480 ciKlass *k = _dependencies.at(i)->as_klass();
1481 ciMethod *m = _dependencies.at(i+1)->as_method();
1482 deps->assert_unique_concrete_method(k, m);
1483 }
1484 }
1485