1 /*
2 * Copyright (c) 2000, 2010, 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.
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21 * questions.
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23 */
24
25 #include "incls/_precompiled.incl"
26 #include "incls/_ciTypeFlow.cpp.incl"
27
28 // ciTypeFlow::JsrSet
29 //
30 // A JsrSet represents some set of JsrRecords. This class
31 // is used to record a set of all jsr routines which we permit
32 // execution to return (ret) from.
33 //
34 // During abstract interpretation, JsrSets are used to determine
35 // whether two paths which reach a given block are unique, and
36 // should be cloned apart, or are compatible, and should merge
37 // together.
38
39 // ------------------------------------------------------------------
40 // ciTypeFlow::JsrSet::JsrSet
41 ciTypeFlow::JsrSet::JsrSet(Arena* arena, int default_len) {
42 if (arena != NULL) {
43 // Allocate growable array in Arena.
44 _set = new (arena) GrowableArray<JsrRecord*>(arena, default_len, 0, NULL);
45 } else {
46 // Allocate growable array in current ResourceArea.
47 _set = new GrowableArray<JsrRecord*>(4, 0, NULL, false);
48 }
49 }
50
51 // ------------------------------------------------------------------
52 // ciTypeFlow::JsrSet::copy_into
53 void ciTypeFlow::JsrSet::copy_into(JsrSet* jsrs) {
54 int len = size();
55 jsrs->_set->clear();
56 for (int i = 0; i < len; i++) {
57 jsrs->_set->append(_set->at(i));
58 }
59 }
60
61 // ------------------------------------------------------------------
62 // ciTypeFlow::JsrSet::is_compatible_with
63 //
64 // !!!! MISGIVINGS ABOUT THIS... disregard
65 //
66 // Is this JsrSet compatible with some other JsrSet?
67 //
68 // In set-theoretic terms, a JsrSet can be viewed as a partial function
69 // from entry addresses to return addresses. Two JsrSets A and B are
70 // compatible iff
71 //
72 // For any x,
73 // A(x) defined and B(x) defined implies A(x) == B(x)
74 //
75 // Less formally, two JsrSets are compatible when they have identical
76 // return addresses for any entry addresses they share in common.
77 bool ciTypeFlow::JsrSet::is_compatible_with(JsrSet* other) {
78 // Walk through both sets in parallel. If the same entry address
79 // appears in both sets, then the return address must match for
80 // the sets to be compatible.
81 int size1 = size();
82 int size2 = other->size();
83
84 // Special case. If nothing is on the jsr stack, then there can
85 // be no ret.
86 if (size2 == 0) {
87 return true;
88 } else if (size1 != size2) {
89 return false;
90 } else {
91 for (int i = 0; i < size1; i++) {
92 JsrRecord* record1 = record_at(i);
93 JsrRecord* record2 = other->record_at(i);
94 if (record1->entry_address() != record2->entry_address() ||
95 record1->return_address() != record2->return_address()) {
96 return false;
97 }
98 }
99 return true;
100 }
101
102 #if 0
103 int pos1 = 0;
104 int pos2 = 0;
105 int size1 = size();
106 int size2 = other->size();
107 while (pos1 < size1 && pos2 < size2) {
108 JsrRecord* record1 = record_at(pos1);
109 JsrRecord* record2 = other->record_at(pos2);
110 int entry1 = record1->entry_address();
111 int entry2 = record2->entry_address();
112 if (entry1 < entry2) {
113 pos1++;
114 } else if (entry1 > entry2) {
115 pos2++;
116 } else {
117 if (record1->return_address() == record2->return_address()) {
118 pos1++;
119 pos2++;
120 } else {
121 // These two JsrSets are incompatible.
122 return false;
123 }
124 }
125 }
126 // The two JsrSets agree.
127 return true;
128 #endif
129 }
130
131 // ------------------------------------------------------------------
132 // ciTypeFlow::JsrSet::insert_jsr_record
133 //
134 // Insert the given JsrRecord into the JsrSet, maintaining the order
135 // of the set and replacing any element with the same entry address.
136 void ciTypeFlow::JsrSet::insert_jsr_record(JsrRecord* record) {
137 int len = size();
138 int entry = record->entry_address();
139 int pos = 0;
140 for ( ; pos < len; pos++) {
141 JsrRecord* current = record_at(pos);
142 if (entry == current->entry_address()) {
143 // Stomp over this entry.
144 _set->at_put(pos, record);
145 assert(size() == len, "must be same size");
146 return;
147 } else if (entry < current->entry_address()) {
148 break;
149 }
150 }
151
152 // Insert the record into the list.
153 JsrRecord* swap = record;
154 JsrRecord* temp = NULL;
155 for ( ; pos < len; pos++) {
156 temp = _set->at(pos);
157 _set->at_put(pos, swap);
158 swap = temp;
159 }
160 _set->append(swap);
161 assert(size() == len+1, "must be larger");
162 }
163
164 // ------------------------------------------------------------------
165 // ciTypeFlow::JsrSet::remove_jsr_record
166 //
167 // Remove the JsrRecord with the given return address from the JsrSet.
168 void ciTypeFlow::JsrSet::remove_jsr_record(int return_address) {
169 int len = size();
170 for (int i = 0; i < len; i++) {
171 if (record_at(i)->return_address() == return_address) {
172 // We have found the proper entry. Remove it from the
173 // JsrSet and exit.
174 for (int j = i+1; j < len ; j++) {
175 _set->at_put(j-1, _set->at(j));
176 }
177 _set->trunc_to(len-1);
178 assert(size() == len-1, "must be smaller");
179 return;
180 }
181 }
182 assert(false, "verify: returning from invalid subroutine");
183 }
184
185 // ------------------------------------------------------------------
186 // ciTypeFlow::JsrSet::apply_control
187 //
188 // Apply the effect of a control-flow bytecode on the JsrSet. The
189 // only bytecodes that modify the JsrSet are jsr and ret.
190 void ciTypeFlow::JsrSet::apply_control(ciTypeFlow* analyzer,
191 ciBytecodeStream* str,
192 ciTypeFlow::StateVector* state) {
193 Bytecodes::Code code = str->cur_bc();
194 if (code == Bytecodes::_jsr) {
195 JsrRecord* record =
196 analyzer->make_jsr_record(str->get_dest(), str->next_bci());
197 insert_jsr_record(record);
198 } else if (code == Bytecodes::_jsr_w) {
199 JsrRecord* record =
200 analyzer->make_jsr_record(str->get_far_dest(), str->next_bci());
201 insert_jsr_record(record);
202 } else if (code == Bytecodes::_ret) {
203 Cell local = state->local(str->get_index());
204 ciType* return_address = state->type_at(local);
205 assert(return_address->is_return_address(), "verify: wrong type");
206 if (size() == 0) {
207 // Ret-state underflow: Hit a ret w/o any previous jsrs. Bail out.
208 // This can happen when a loop is inside a finally clause (4614060).
209 analyzer->record_failure("OSR in finally clause");
210 return;
211 }
212 remove_jsr_record(return_address->as_return_address()->bci());
213 }
214 }
215
216 #ifndef PRODUCT
217 // ------------------------------------------------------------------
218 // ciTypeFlow::JsrSet::print_on
219 void ciTypeFlow::JsrSet::print_on(outputStream* st) const {
220 st->print("{ ");
221 int num_elements = size();
222 if (num_elements > 0) {
223 int i = 0;
224 for( ; i < num_elements - 1; i++) {
225 _set->at(i)->print_on(st);
226 st->print(", ");
227 }
228 _set->at(i)->print_on(st);
229 st->print(" ");
230 }
231 st->print("}");
232 }
233 #endif
234
235 // ciTypeFlow::StateVector
236 //
237 // A StateVector summarizes the type information at some point in
238 // the program.
239
240 // ------------------------------------------------------------------
241 // ciTypeFlow::StateVector::type_meet
242 //
243 // Meet two types.
244 //
245 // The semi-lattice of types use by this analysis are modeled on those
246 // of the verifier. The lattice is as follows:
247 //
248 // top_type() >= all non-extremal types >= bottom_type
249 // and
250 // Every primitive type is comparable only with itself. The meet of
251 // reference types is determined by their kind: instance class,
252 // interface, or array class. The meet of two types of the same
253 // kind is their least common ancestor. The meet of two types of
254 // different kinds is always java.lang.Object.
255 ciType* ciTypeFlow::StateVector::type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer) {
256 assert(t1 != t2, "checked in caller");
257 if (t1->equals(top_type())) {
258 return t2;
259 } else if (t2->equals(top_type())) {
260 return t1;
261 } else if (t1->is_primitive_type() || t2->is_primitive_type()) {
262 // Special case null_type. null_type meet any reference type T
263 // is T. null_type meet null_type is null_type.
264 if (t1->equals(null_type())) {
265 if (!t2->is_primitive_type() || t2->equals(null_type())) {
266 return t2;
267 }
268 } else if (t2->equals(null_type())) {
269 if (!t1->is_primitive_type()) {
270 return t1;
271 }
272 }
273
274 // At least one of the two types is a non-top primitive type.
275 // The other type is not equal to it. Fall to bottom.
276 return bottom_type();
277 } else {
278 // Both types are non-top non-primitive types. That is,
279 // both types are either instanceKlasses or arrayKlasses.
280 ciKlass* object_klass = analyzer->env()->Object_klass();
281 ciKlass* k1 = t1->as_klass();
282 ciKlass* k2 = t2->as_klass();
283 if (k1->equals(object_klass) || k2->equals(object_klass)) {
284 return object_klass;
285 } else if (!k1->is_loaded() || !k2->is_loaded()) {
286 // Unloaded classes fall to java.lang.Object at a merge.
287 return object_klass;
288 } else if (k1->is_interface() != k2->is_interface()) {
289 // When an interface meets a non-interface, we get Object;
290 // This is what the verifier does.
291 return object_klass;
292 } else if (k1->is_array_klass() || k2->is_array_klass()) {
293 // When an array meets a non-array, we get Object.
294 // When objArray meets typeArray, we also get Object.
295 // And when typeArray meets different typeArray, we again get Object.
296 // But when objArray meets objArray, we look carefully at element types.
297 if (k1->is_obj_array_klass() && k2->is_obj_array_klass()) {
298 // Meet the element types, then construct the corresponding array type.
299 ciKlass* elem1 = k1->as_obj_array_klass()->element_klass();
300 ciKlass* elem2 = k2->as_obj_array_klass()->element_klass();
301 ciKlass* elem = type_meet_internal(elem1, elem2, analyzer)->as_klass();
302 // Do an easy shortcut if one type is a super of the other.
303 if (elem == elem1) {
304 assert(k1 == ciObjArrayKlass::make(elem), "shortcut is OK");
305 return k1;
306 } else if (elem == elem2) {
307 assert(k2 == ciObjArrayKlass::make(elem), "shortcut is OK");
308 return k2;
309 } else {
310 return ciObjArrayKlass::make(elem);
311 }
312 } else {
313 return object_klass;
314 }
315 } else {
316 // Must be two plain old instance klasses.
317 assert(k1->is_instance_klass(), "previous cases handle non-instances");
318 assert(k2->is_instance_klass(), "previous cases handle non-instances");
319 return k1->least_common_ancestor(k2);
320 }
321 }
322 }
323
324
325 // ------------------------------------------------------------------
326 // ciTypeFlow::StateVector::StateVector
327 //
328 // Build a new state vector
329 ciTypeFlow::StateVector::StateVector(ciTypeFlow* analyzer) {
330 _outer = analyzer;
331 _stack_size = -1;
332 _monitor_count = -1;
333 // Allocate the _types array
334 int max_cells = analyzer->max_cells();
335 _types = (ciType**)analyzer->arena()->Amalloc(sizeof(ciType*) * max_cells);
336 for (int i=0; i<max_cells; i++) {
337 _types[i] = top_type();
338 }
339 _trap_bci = -1;
340 _trap_index = 0;
341 _def_locals.clear();
342 }
343
344
345 // ------------------------------------------------------------------
346 // ciTypeFlow::get_start_state
347 //
348 // Set this vector to the method entry state.
349 const ciTypeFlow::StateVector* ciTypeFlow::get_start_state() {
350 StateVector* state = new StateVector(this);
351 if (is_osr_flow()) {
352 ciTypeFlow* non_osr_flow = method()->get_flow_analysis();
353 if (non_osr_flow->failing()) {
354 record_failure(non_osr_flow->failure_reason());
355 return NULL;
356 }
357 JsrSet* jsrs = new JsrSet(NULL, 16);
358 Block* non_osr_block = non_osr_flow->existing_block_at(start_bci(), jsrs);
359 if (non_osr_block == NULL) {
360 record_failure("cannot reach OSR point");
361 return NULL;
362 }
363 // load up the non-OSR state at this point
364 non_osr_block->copy_state_into(state);
365 int non_osr_start = non_osr_block->start();
366 if (non_osr_start != start_bci()) {
367 // must flow forward from it
368 if (CITraceTypeFlow) {
369 tty->print_cr(">> Interpreting pre-OSR block %d:", non_osr_start);
370 }
371 Block* block = block_at(non_osr_start, jsrs);
372 assert(block->limit() == start_bci(), "must flow forward to start");
373 flow_block(block, state, jsrs);
374 }
375 return state;
376 // Note: The code below would be an incorrect for an OSR flow,
377 // even if it were possible for an OSR entry point to be at bci zero.
378 }
379 // "Push" the method signature into the first few locals.
380 state->set_stack_size(-max_locals());
381 if (!method()->is_static()) {
382 state->push(method()->holder());
383 assert(state->tos() == state->local(0), "");
384 }
385 for (ciSignatureStream str(method()->signature());
386 !str.at_return_type();
387 str.next()) {
388 state->push_translate(str.type());
389 }
390 // Set the rest of the locals to bottom.
391 Cell cell = state->next_cell(state->tos());
392 state->set_stack_size(0);
393 int limit = state->limit_cell();
394 for (; cell < limit; cell = state->next_cell(cell)) {
395 state->set_type_at(cell, state->bottom_type());
396 }
397 // Lock an object, if necessary.
398 state->set_monitor_count(method()->is_synchronized() ? 1 : 0);
399 return state;
400 }
401
402 // ------------------------------------------------------------------
403 // ciTypeFlow::StateVector::copy_into
404 //
405 // Copy our value into some other StateVector
406 void ciTypeFlow::StateVector::copy_into(ciTypeFlow::StateVector* copy)
407 const {
408 copy->set_stack_size(stack_size());
409 copy->set_monitor_count(monitor_count());
410 Cell limit = limit_cell();
411 for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
412 copy->set_type_at(c, type_at(c));
413 }
414 }
415
416 // ------------------------------------------------------------------
417 // ciTypeFlow::StateVector::meet
418 //
419 // Meets this StateVector with another, destructively modifying this
420 // one. Returns true if any modification takes place.
421 bool ciTypeFlow::StateVector::meet(const ciTypeFlow::StateVector* incoming) {
422 if (monitor_count() == -1) {
423 set_monitor_count(incoming->monitor_count());
424 }
425 assert(monitor_count() == incoming->monitor_count(), "monitors must match");
426
427 if (stack_size() == -1) {
428 set_stack_size(incoming->stack_size());
429 Cell limit = limit_cell();
430 #ifdef ASSERT
431 { for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
432 assert(type_at(c) == top_type(), "");
433 } }
434 #endif
435 // Make a simple copy of the incoming state.
436 for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
437 set_type_at(c, incoming->type_at(c));
438 }
439 return true; // it is always different the first time
440 }
441 #ifdef ASSERT
442 if (stack_size() != incoming->stack_size()) {
443 _outer->method()->print_codes();
444 tty->print_cr("!!!! Stack size conflict");
445 tty->print_cr("Current state:");
446 print_on(tty);
447 tty->print_cr("Incoming state:");
448 ((StateVector*)incoming)->print_on(tty);
449 }
450 #endif
451 assert(stack_size() == incoming->stack_size(), "sanity");
452
453 bool different = false;
454 Cell limit = limit_cell();
455 for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
456 ciType* t1 = type_at(c);
457 ciType* t2 = incoming->type_at(c);
458 if (!t1->equals(t2)) {
459 ciType* new_type = type_meet(t1, t2);
460 if (!t1->equals(new_type)) {
461 set_type_at(c, new_type);
462 different = true;
463 }
464 }
465 }
466 return different;
467 }
468
469 // ------------------------------------------------------------------
470 // ciTypeFlow::StateVector::meet_exception
471 //
472 // Meets this StateVector with another, destructively modifying this
473 // one. The incoming state is coming via an exception. Returns true
474 // if any modification takes place.
475 bool ciTypeFlow::StateVector::meet_exception(ciInstanceKlass* exc,
476 const ciTypeFlow::StateVector* incoming) {
477 if (monitor_count() == -1) {
478 set_monitor_count(incoming->monitor_count());
479 }
480 assert(monitor_count() == incoming->monitor_count(), "monitors must match");
481
482 if (stack_size() == -1) {
483 set_stack_size(1);
484 }
485
486 assert(stack_size() == 1, "must have one-element stack");
487
488 bool different = false;
489
490 // Meet locals from incoming array.
491 Cell limit = local(_outer->max_locals()-1);
492 for (Cell c = start_cell(); c <= limit; c = next_cell(c)) {
493 ciType* t1 = type_at(c);
494 ciType* t2 = incoming->type_at(c);
495 if (!t1->equals(t2)) {
496 ciType* new_type = type_meet(t1, t2);
497 if (!t1->equals(new_type)) {
498 set_type_at(c, new_type);
499 different = true;
500 }
501 }
502 }
503
504 // Handle stack separately. When an exception occurs, the
505 // only stack entry is the exception instance.
506 ciType* tos_type = type_at_tos();
507 if (!tos_type->equals(exc)) {
508 ciType* new_type = type_meet(tos_type, exc);
509 if (!tos_type->equals(new_type)) {
510 set_type_at_tos(new_type);
511 different = true;
512 }
513 }
514
515 return different;
516 }
517
518 // ------------------------------------------------------------------
519 // ciTypeFlow::StateVector::push_translate
520 void ciTypeFlow::StateVector::push_translate(ciType* type) {
521 BasicType basic_type = type->basic_type();
522 if (basic_type == T_BOOLEAN || basic_type == T_CHAR ||
523 basic_type == T_BYTE || basic_type == T_SHORT) {
524 push_int();
525 } else {
526 push(type);
527 if (type->is_two_word()) {
528 push(half_type(type));
529 }
530 }
531 }
532
533 // ------------------------------------------------------------------
534 // ciTypeFlow::StateVector::do_aaload
535 void ciTypeFlow::StateVector::do_aaload(ciBytecodeStream* str) {
536 pop_int();
537 ciObjArrayKlass* array_klass = pop_objArray();
538 if (array_klass == NULL) {
539 // Did aaload on a null reference; push a null and ignore the exception.
540 // This instruction will never continue normally. All we have to do
541 // is report a value that will meet correctly with any downstream
542 // reference types on paths that will truly be executed. This null type
543 // meets with any reference type to yield that same reference type.
544 // (The compiler will generate an unconditional exception here.)
545 push(null_type());
546 return;
547 }
548 if (!array_klass->is_loaded()) {
549 // Only fails for some -Xcomp runs
550 trap(str, array_klass,
551 Deoptimization::make_trap_request
552 (Deoptimization::Reason_unloaded,
553 Deoptimization::Action_reinterpret));
554 return;
555 }
556 ciKlass* element_klass = array_klass->element_klass();
557 if (!element_klass->is_loaded() && element_klass->is_instance_klass()) {
558 Untested("unloaded array element class in ciTypeFlow");
559 trap(str, element_klass,
560 Deoptimization::make_trap_request
561 (Deoptimization::Reason_unloaded,
562 Deoptimization::Action_reinterpret));
563 } else {
564 push_object(element_klass);
565 }
566 }
567
568
569 // ------------------------------------------------------------------
570 // ciTypeFlow::StateVector::do_checkcast
571 void ciTypeFlow::StateVector::do_checkcast(ciBytecodeStream* str) {
572 bool will_link;
573 ciKlass* klass = str->get_klass(will_link);
574 if (!will_link) {
575 // VM's interpreter will not load 'klass' if object is NULL.
576 // Type flow after this block may still be needed in two situations:
577 // 1) C2 uses do_null_assert() and continues compilation for later blocks
578 // 2) C2 does an OSR compile in a later block (see bug 4778368).
579 pop_object();
580 do_null_assert(klass);
581 } else {
582 pop_object();
583 push_object(klass);
584 }
585 }
586
587 // ------------------------------------------------------------------
588 // ciTypeFlow::StateVector::do_getfield
589 void ciTypeFlow::StateVector::do_getfield(ciBytecodeStream* str) {
590 // could add assert here for type of object.
591 pop_object();
592 do_getstatic(str);
593 }
594
595 // ------------------------------------------------------------------
596 // ciTypeFlow::StateVector::do_getstatic
597 void ciTypeFlow::StateVector::do_getstatic(ciBytecodeStream* str) {
598 bool will_link;
599 ciField* field = str->get_field(will_link);
600 if (!will_link) {
601 trap(str, field->holder(), str->get_field_holder_index());
602 } else {
603 ciType* field_type = field->type();
604 if (!field_type->is_loaded()) {
605 // Normally, we need the field's type to be loaded if we are to
606 // do anything interesting with its value.
607 // We used to do this: trap(str, str->get_field_signature_index());
608 //
609 // There is one good reason not to trap here. Execution can
610 // get past this "getfield" or "getstatic" if the value of
611 // the field is null. As long as the value is null, the class
612 // does not need to be loaded! The compiler must assume that
613 // the value of the unloaded class reference is null; if the code
614 // ever sees a non-null value, loading has occurred.
615 //
616 // This actually happens often enough to be annoying. If the
617 // compiler throws an uncommon trap at this bytecode, you can
618 // get an endless loop of recompilations, when all the code
619 // needs to do is load a series of null values. Also, a trap
620 // here can make an OSR entry point unreachable, triggering the
621 // assert on non_osr_block in ciTypeFlow::get_start_state.
622 // (See bug 4379915.)
623 do_null_assert(field_type->as_klass());
624 } else {
625 push_translate(field_type);
626 }
627 }
628 }
629
630 // ------------------------------------------------------------------
631 // ciTypeFlow::StateVector::do_invoke
632 void ciTypeFlow::StateVector::do_invoke(ciBytecodeStream* str,
633 bool has_receiver) {
634 bool will_link;
635 ciMethod* method = str->get_method(will_link);
636 if (!will_link) {
637 // We weren't able to find the method.
638 if (str->cur_bc() == Bytecodes::_invokedynamic) {
639 trap(str, NULL,
640 Deoptimization::make_trap_request
641 (Deoptimization::Reason_uninitialized,
642 Deoptimization::Action_reinterpret));
643 } else {
644 ciKlass* unloaded_holder = method->holder();
645 trap(str, unloaded_holder, str->get_method_holder_index());
646 }
647 } else {
648 ciSignature* signature = method->signature();
649 ciSignatureStream sigstr(signature);
650 int arg_size = signature->size();
651 int stack_base = stack_size() - arg_size;
652 int i = 0;
653 for( ; !sigstr.at_return_type(); sigstr.next()) {
654 ciType* type = sigstr.type();
655 ciType* stack_type = type_at(stack(stack_base + i++));
656 // Do I want to check this type?
657 // assert(stack_type->is_subtype_of(type), "bad type for field value");
658 if (type->is_two_word()) {
659 ciType* stack_type2 = type_at(stack(stack_base + i++));
660 assert(stack_type2->equals(half_type(type)), "must be 2nd half");
661 }
662 }
663 assert(arg_size == i, "must match");
664 for (int j = 0; j < arg_size; j++) {
665 pop();
666 }
667 if (has_receiver) {
668 // Check this?
669 pop_object();
670 }
671 assert(!sigstr.is_done(), "must have return type");
672 ciType* return_type = sigstr.type();
673 if (!return_type->is_void()) {
674 if (!return_type->is_loaded()) {
675 // As in do_getstatic(), generally speaking, we need the return type to
676 // be loaded if we are to do anything interesting with its value.
677 // We used to do this: trap(str, str->get_method_signature_index());
678 //
679 // We do not trap here since execution can get past this invoke if
680 // the return value is null. As long as the value is null, the class
681 // does not need to be loaded! The compiler must assume that
682 // the value of the unloaded class reference is null; if the code
683 // ever sees a non-null value, loading has occurred.
684 //
685 // See do_getstatic() for similar explanation, as well as bug 4684993.
686 do_null_assert(return_type->as_klass());
687 } else {
688 push_translate(return_type);
689 }
690 }
691 }
692 }
693
694 // ------------------------------------------------------------------
695 // ciTypeFlow::StateVector::do_jsr
696 void ciTypeFlow::StateVector::do_jsr(ciBytecodeStream* str) {
697 push(ciReturnAddress::make(str->next_bci()));
698 }
699
700 // ------------------------------------------------------------------
701 // ciTypeFlow::StateVector::do_ldc
702 void ciTypeFlow::StateVector::do_ldc(ciBytecodeStream* str) {
703 ciConstant con = str->get_constant();
704 BasicType basic_type = con.basic_type();
705 if (basic_type == T_ILLEGAL) {
706 // OutOfMemoryError in the CI while loading constant
707 push_null();
708 outer()->record_failure("ldc did not link");
709 return;
710 }
711 if (basic_type == T_OBJECT || basic_type == T_ARRAY) {
712 ciObject* obj = con.as_object();
713 if (obj->is_null_object()) {
714 push_null();
715 } else {
716 assert(!obj->is_klass(), "must be java_mirror of klass");
717 push_object(obj->klass());
718 }
719 } else {
720 push_translate(ciType::make(basic_type));
721 }
722 }
723
724 // ------------------------------------------------------------------
725 // ciTypeFlow::StateVector::do_multianewarray
726 void ciTypeFlow::StateVector::do_multianewarray(ciBytecodeStream* str) {
727 int dimensions = str->get_dimensions();
728 bool will_link;
729 ciArrayKlass* array_klass = str->get_klass(will_link)->as_array_klass();
730 if (!will_link) {
731 trap(str, array_klass, str->get_klass_index());
732 } else {
733 for (int i = 0; i < dimensions; i++) {
734 pop_int();
735 }
736 push_object(array_klass);
737 }
738 }
739
740 // ------------------------------------------------------------------
741 // ciTypeFlow::StateVector::do_new
742 void ciTypeFlow::StateVector::do_new(ciBytecodeStream* str) {
743 bool will_link;
744 ciKlass* klass = str->get_klass(will_link);
745 if (!will_link || str->is_unresolved_klass()) {
746 trap(str, klass, str->get_klass_index());
747 } else {
748 push_object(klass);
749 }
750 }
751
752 // ------------------------------------------------------------------
753 // ciTypeFlow::StateVector::do_newarray
754 void ciTypeFlow::StateVector::do_newarray(ciBytecodeStream* str) {
755 pop_int();
756 ciKlass* klass = ciTypeArrayKlass::make((BasicType)str->get_index());
757 push_object(klass);
758 }
759
760 // ------------------------------------------------------------------
761 // ciTypeFlow::StateVector::do_putfield
762 void ciTypeFlow::StateVector::do_putfield(ciBytecodeStream* str) {
763 do_putstatic(str);
764 if (_trap_bci != -1) return; // unloaded field holder, etc.
765 // could add assert here for type of object.
766 pop_object();
767 }
768
769 // ------------------------------------------------------------------
770 // ciTypeFlow::StateVector::do_putstatic
771 void ciTypeFlow::StateVector::do_putstatic(ciBytecodeStream* str) {
772 bool will_link;
773 ciField* field = str->get_field(will_link);
774 if (!will_link) {
775 trap(str, field->holder(), str->get_field_holder_index());
776 } else {
777 ciType* field_type = field->type();
778 ciType* type = pop_value();
779 // Do I want to check this type?
780 // assert(type->is_subtype_of(field_type), "bad type for field value");
781 if (field_type->is_two_word()) {
782 ciType* type2 = pop_value();
783 assert(type2->is_two_word(), "must be 2nd half");
784 assert(type == half_type(type2), "must be 2nd half");
785 }
786 }
787 }
788
789 // ------------------------------------------------------------------
790 // ciTypeFlow::StateVector::do_ret
791 void ciTypeFlow::StateVector::do_ret(ciBytecodeStream* str) {
792 Cell index = local(str->get_index());
793
794 ciType* address = type_at(index);
795 assert(address->is_return_address(), "bad return address");
796 set_type_at(index, bottom_type());
797 }
798
799 // ------------------------------------------------------------------
800 // ciTypeFlow::StateVector::trap
801 //
802 // Stop interpretation of this path with a trap.
803 void ciTypeFlow::StateVector::trap(ciBytecodeStream* str, ciKlass* klass, int index) {
804 _trap_bci = str->cur_bci();
805 _trap_index = index;
806
807 // Log information about this trap:
808 CompileLog* log = outer()->env()->log();
809 if (log != NULL) {
810 int mid = log->identify(outer()->method());
811 int kid = (klass == NULL)? -1: log->identify(klass);
812 log->begin_elem("uncommon_trap method='%d' bci='%d'", mid, str->cur_bci());
813 char buf[100];
814 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
815 index));
816 if (kid >= 0)
817 log->print(" klass='%d'", kid);
818 log->end_elem();
819 }
820 }
821
822 // ------------------------------------------------------------------
823 // ciTypeFlow::StateVector::do_null_assert
824 // Corresponds to graphKit::do_null_assert.
825 void ciTypeFlow::StateVector::do_null_assert(ciKlass* unloaded_klass) {
826 if (unloaded_klass->is_loaded()) {
827 // We failed to link, but we can still compute with this class,
828 // since it is loaded somewhere. The compiler will uncommon_trap
829 // if the object is not null, but the typeflow pass can not assume
830 // that the object will be null, otherwise it may incorrectly tell
831 // the parser that an object is known to be null. 4761344, 4807707
832 push_object(unloaded_klass);
833 } else {
834 // The class is not loaded anywhere. It is safe to model the
835 // null in the typestates, because we can compile in a null check
836 // which will deoptimize us if someone manages to load the
837 // class later.
838 push_null();
839 }
840 }
841
842
843 // ------------------------------------------------------------------
844 // ciTypeFlow::StateVector::apply_one_bytecode
845 //
846 // Apply the effect of one bytecode to this StateVector
847 bool ciTypeFlow::StateVector::apply_one_bytecode(ciBytecodeStream* str) {
848 _trap_bci = -1;
849 _trap_index = 0;
850
851 if (CITraceTypeFlow) {
852 tty->print_cr(">> Interpreting bytecode %d:%s", str->cur_bci(),
853 Bytecodes::name(str->cur_bc()));
854 }
855
856 switch(str->cur_bc()) {
857 case Bytecodes::_aaload: do_aaload(str); break;
858
859 case Bytecodes::_aastore:
860 {
861 pop_object();
862 pop_int();
863 pop_objArray();
864 break;
865 }
866 case Bytecodes::_aconst_null:
867 {
868 push_null();
869 break;
870 }
871 case Bytecodes::_aload: load_local_object(str->get_index()); break;
872 case Bytecodes::_aload_0: load_local_object(0); break;
873 case Bytecodes::_aload_1: load_local_object(1); break;
874 case Bytecodes::_aload_2: load_local_object(2); break;
875 case Bytecodes::_aload_3: load_local_object(3); break;
876
877 case Bytecodes::_anewarray:
878 {
879 pop_int();
880 bool will_link;
881 ciKlass* element_klass = str->get_klass(will_link);
882 if (!will_link) {
883 trap(str, element_klass, str->get_klass_index());
884 } else {
885 push_object(ciObjArrayKlass::make(element_klass));
886 }
887 break;
888 }
889 case Bytecodes::_areturn:
890 case Bytecodes::_ifnonnull:
891 case Bytecodes::_ifnull:
892 {
893 pop_object();
894 break;
895 }
896 case Bytecodes::_monitorenter:
897 {
898 pop_object();
899 set_monitor_count(monitor_count() + 1);
900 break;
901 }
902 case Bytecodes::_monitorexit:
903 {
904 pop_object();
905 assert(monitor_count() > 0, "must be a monitor to exit from");
906 set_monitor_count(monitor_count() - 1);
907 break;
908 }
909 case Bytecodes::_arraylength:
910 {
911 pop_array();
912 push_int();
913 break;
914 }
915 case Bytecodes::_astore: store_local_object(str->get_index()); break;
916 case Bytecodes::_astore_0: store_local_object(0); break;
917 case Bytecodes::_astore_1: store_local_object(1); break;
918 case Bytecodes::_astore_2: store_local_object(2); break;
919 case Bytecodes::_astore_3: store_local_object(3); break;
920
921 case Bytecodes::_athrow:
922 {
923 NEEDS_CLEANUP;
924 pop_object();
925 break;
926 }
927 case Bytecodes::_baload:
928 case Bytecodes::_caload:
929 case Bytecodes::_iaload:
930 case Bytecodes::_saload:
931 {
932 pop_int();
933 ciTypeArrayKlass* array_klass = pop_typeArray();
934 // Put assert here for right type?
935 push_int();
936 break;
937 }
938 case Bytecodes::_bastore:
939 case Bytecodes::_castore:
940 case Bytecodes::_iastore:
941 case Bytecodes::_sastore:
942 {
943 pop_int();
944 pop_int();
945 pop_typeArray();
946 // assert here?
947 break;
948 }
949 case Bytecodes::_bipush:
950 case Bytecodes::_iconst_m1:
951 case Bytecodes::_iconst_0:
952 case Bytecodes::_iconst_1:
953 case Bytecodes::_iconst_2:
954 case Bytecodes::_iconst_3:
955 case Bytecodes::_iconst_4:
956 case Bytecodes::_iconst_5:
957 case Bytecodes::_sipush:
958 {
959 push_int();
960 break;
961 }
962 case Bytecodes::_checkcast: do_checkcast(str); break;
963
964 case Bytecodes::_d2f:
965 {
966 pop_double();
967 push_float();
968 break;
969 }
970 case Bytecodes::_d2i:
971 {
972 pop_double();
973 push_int();
974 break;
975 }
976 case Bytecodes::_d2l:
977 {
978 pop_double();
979 push_long();
980 break;
981 }
982 case Bytecodes::_dadd:
983 case Bytecodes::_ddiv:
984 case Bytecodes::_dmul:
985 case Bytecodes::_drem:
986 case Bytecodes::_dsub:
987 {
988 pop_double();
989 pop_double();
990 push_double();
991 break;
992 }
993 case Bytecodes::_daload:
994 {
995 pop_int();
996 ciTypeArrayKlass* array_klass = pop_typeArray();
997 // Put assert here for right type?
998 push_double();
999 break;
1000 }
1001 case Bytecodes::_dastore:
1002 {
1003 pop_double();
1004 pop_int();
1005 pop_typeArray();
1006 // assert here?
1007 break;
1008 }
1009 case Bytecodes::_dcmpg:
1010 case Bytecodes::_dcmpl:
1011 {
1012 pop_double();
1013 pop_double();
1014 push_int();
1015 break;
1016 }
1017 case Bytecodes::_dconst_0:
1018 case Bytecodes::_dconst_1:
1019 {
1020 push_double();
1021 break;
1022 }
1023 case Bytecodes::_dload: load_local_double(str->get_index()); break;
1024 case Bytecodes::_dload_0: load_local_double(0); break;
1025 case Bytecodes::_dload_1: load_local_double(1); break;
1026 case Bytecodes::_dload_2: load_local_double(2); break;
1027 case Bytecodes::_dload_3: load_local_double(3); break;
1028
1029 case Bytecodes::_dneg:
1030 {
1031 pop_double();
1032 push_double();
1033 break;
1034 }
1035 case Bytecodes::_dreturn:
1036 {
1037 pop_double();
1038 break;
1039 }
1040 case Bytecodes::_dstore: store_local_double(str->get_index()); break;
1041 case Bytecodes::_dstore_0: store_local_double(0); break;
1042 case Bytecodes::_dstore_1: store_local_double(1); break;
1043 case Bytecodes::_dstore_2: store_local_double(2); break;
1044 case Bytecodes::_dstore_3: store_local_double(3); break;
1045
1046 case Bytecodes::_dup:
1047 {
1048 push(type_at_tos());
1049 break;
1050 }
1051 case Bytecodes::_dup_x1:
1052 {
1053 ciType* value1 = pop_value();
1054 ciType* value2 = pop_value();
1055 push(value1);
1056 push(value2);
1057 push(value1);
1058 break;
1059 }
1060 case Bytecodes::_dup_x2:
1061 {
1062 ciType* value1 = pop_value();
1063 ciType* value2 = pop_value();
1064 ciType* value3 = pop_value();
1065 push(value1);
1066 push(value3);
1067 push(value2);
1068 push(value1);
1069 break;
1070 }
1071 case Bytecodes::_dup2:
1072 {
1073 ciType* value1 = pop_value();
1074 ciType* value2 = pop_value();
1075 push(value2);
1076 push(value1);
1077 push(value2);
1078 push(value1);
1079 break;
1080 }
1081 case Bytecodes::_dup2_x1:
1082 {
1083 ciType* value1 = pop_value();
1084 ciType* value2 = pop_value();
1085 ciType* value3 = pop_value();
1086 push(value2);
1087 push(value1);
1088 push(value3);
1089 push(value2);
1090 push(value1);
1091 break;
1092 }
1093 case Bytecodes::_dup2_x2:
1094 {
1095 ciType* value1 = pop_value();
1096 ciType* value2 = pop_value();
1097 ciType* value3 = pop_value();
1098 ciType* value4 = pop_value();
1099 push(value2);
1100 push(value1);
1101 push(value4);
1102 push(value3);
1103 push(value2);
1104 push(value1);
1105 break;
1106 }
1107 case Bytecodes::_f2d:
1108 {
1109 pop_float();
1110 push_double();
1111 break;
1112 }
1113 case Bytecodes::_f2i:
1114 {
1115 pop_float();
1116 push_int();
1117 break;
1118 }
1119 case Bytecodes::_f2l:
1120 {
1121 pop_float();
1122 push_long();
1123 break;
1124 }
1125 case Bytecodes::_fadd:
1126 case Bytecodes::_fdiv:
1127 case Bytecodes::_fmul:
1128 case Bytecodes::_frem:
1129 case Bytecodes::_fsub:
1130 {
1131 pop_float();
1132 pop_float();
1133 push_float();
1134 break;
1135 }
1136 case Bytecodes::_faload:
1137 {
1138 pop_int();
1139 ciTypeArrayKlass* array_klass = pop_typeArray();
1140 // Put assert here.
1141 push_float();
1142 break;
1143 }
1144 case Bytecodes::_fastore:
1145 {
1146 pop_float();
1147 pop_int();
1148 ciTypeArrayKlass* array_klass = pop_typeArray();
1149 // Put assert here.
1150 break;
1151 }
1152 case Bytecodes::_fcmpg:
1153 case Bytecodes::_fcmpl:
1154 {
1155 pop_float();
1156 pop_float();
1157 push_int();
1158 break;
1159 }
1160 case Bytecodes::_fconst_0:
1161 case Bytecodes::_fconst_1:
1162 case Bytecodes::_fconst_2:
1163 {
1164 push_float();
1165 break;
1166 }
1167 case Bytecodes::_fload: load_local_float(str->get_index()); break;
1168 case Bytecodes::_fload_0: load_local_float(0); break;
1169 case Bytecodes::_fload_1: load_local_float(1); break;
1170 case Bytecodes::_fload_2: load_local_float(2); break;
1171 case Bytecodes::_fload_3: load_local_float(3); break;
1172
1173 case Bytecodes::_fneg:
1174 {
1175 pop_float();
1176 push_float();
1177 break;
1178 }
1179 case Bytecodes::_freturn:
1180 {
1181 pop_float();
1182 break;
1183 }
1184 case Bytecodes::_fstore: store_local_float(str->get_index()); break;
1185 case Bytecodes::_fstore_0: store_local_float(0); break;
1186 case Bytecodes::_fstore_1: store_local_float(1); break;
1187 case Bytecodes::_fstore_2: store_local_float(2); break;
1188 case Bytecodes::_fstore_3: store_local_float(3); break;
1189
1190 case Bytecodes::_getfield: do_getfield(str); break;
1191 case Bytecodes::_getstatic: do_getstatic(str); break;
1192
1193 case Bytecodes::_goto:
1194 case Bytecodes::_goto_w:
1195 case Bytecodes::_nop:
1196 case Bytecodes::_return:
1197 {
1198 // do nothing.
1199 break;
1200 }
1201 case Bytecodes::_i2b:
1202 case Bytecodes::_i2c:
1203 case Bytecodes::_i2s:
1204 case Bytecodes::_ineg:
1205 {
1206 pop_int();
1207 push_int();
1208 break;
1209 }
1210 case Bytecodes::_i2d:
1211 {
1212 pop_int();
1213 push_double();
1214 break;
1215 }
1216 case Bytecodes::_i2f:
1217 {
1218 pop_int();
1219 push_float();
1220 break;
1221 }
1222 case Bytecodes::_i2l:
1223 {
1224 pop_int();
1225 push_long();
1226 break;
1227 }
1228 case Bytecodes::_iadd:
1229 case Bytecodes::_iand:
1230 case Bytecodes::_idiv:
1231 case Bytecodes::_imul:
1232 case Bytecodes::_ior:
1233 case Bytecodes::_irem:
1234 case Bytecodes::_ishl:
1235 case Bytecodes::_ishr:
1236 case Bytecodes::_isub:
1237 case Bytecodes::_iushr:
1238 case Bytecodes::_ixor:
1239 {
1240 pop_int();
1241 pop_int();
1242 push_int();
1243 break;
1244 }
1245 case Bytecodes::_if_acmpeq:
1246 case Bytecodes::_if_acmpne:
1247 {
1248 pop_object();
1249 pop_object();
1250 break;
1251 }
1252 case Bytecodes::_if_icmpeq:
1253 case Bytecodes::_if_icmpge:
1254 case Bytecodes::_if_icmpgt:
1255 case Bytecodes::_if_icmple:
1256 case Bytecodes::_if_icmplt:
1257 case Bytecodes::_if_icmpne:
1258 {
1259 pop_int();
1260 pop_int();
1261 break;
1262 }
1263 case Bytecodes::_ifeq:
1264 case Bytecodes::_ifle:
1265 case Bytecodes::_iflt:
1266 case Bytecodes::_ifge:
1267 case Bytecodes::_ifgt:
1268 case Bytecodes::_ifne:
1269 case Bytecodes::_ireturn:
1270 case Bytecodes::_lookupswitch:
1271 case Bytecodes::_tableswitch:
1272 {
1273 pop_int();
1274 break;
1275 }
1276 case Bytecodes::_iinc:
1277 {
1278 int lnum = str->get_index();
1279 check_int(local(lnum));
1280 store_to_local(lnum);
1281 break;
1282 }
1283 case Bytecodes::_iload: load_local_int(str->get_index()); break;
1284 case Bytecodes::_iload_0: load_local_int(0); break;
1285 case Bytecodes::_iload_1: load_local_int(1); break;
1286 case Bytecodes::_iload_2: load_local_int(2); break;
1287 case Bytecodes::_iload_3: load_local_int(3); break;
1288
1289 case Bytecodes::_instanceof:
1290 {
1291 // Check for uncommon trap:
1292 do_checkcast(str);
1293 pop_object();
1294 push_int();
1295 break;
1296 }
1297 case Bytecodes::_invokeinterface: do_invoke(str, true); break;
1298 case Bytecodes::_invokespecial: do_invoke(str, true); break;
1299 case Bytecodes::_invokestatic: do_invoke(str, false); break;
1300 case Bytecodes::_invokevirtual: do_invoke(str, true); break;
1301 case Bytecodes::_invokedynamic: do_invoke(str, false); break;
1302
1303 case Bytecodes::_istore: store_local_int(str->get_index()); break;
1304 case Bytecodes::_istore_0: store_local_int(0); break;
1305 case Bytecodes::_istore_1: store_local_int(1); break;
1306 case Bytecodes::_istore_2: store_local_int(2); break;
1307 case Bytecodes::_istore_3: store_local_int(3); break;
1308
1309 case Bytecodes::_jsr:
1310 case Bytecodes::_jsr_w: do_jsr(str); break;
1311
1312 case Bytecodes::_l2d:
1313 {
1314 pop_long();
1315 push_double();
1316 break;
1317 }
1318 case Bytecodes::_l2f:
1319 {
1320 pop_long();
1321 push_float();
1322 break;
1323 }
1324 case Bytecodes::_l2i:
1325 {
1326 pop_long();
1327 push_int();
1328 break;
1329 }
1330 case Bytecodes::_ladd:
1331 case Bytecodes::_land:
1332 case Bytecodes::_ldiv:
1333 case Bytecodes::_lmul:
1334 case Bytecodes::_lor:
1335 case Bytecodes::_lrem:
1336 case Bytecodes::_lsub:
1337 case Bytecodes::_lxor:
1338 {
1339 pop_long();
1340 pop_long();
1341 push_long();
1342 break;
1343 }
1344 case Bytecodes::_laload:
1345 {
1346 pop_int();
1347 ciTypeArrayKlass* array_klass = pop_typeArray();
1348 // Put assert here for right type?
1349 push_long();
1350 break;
1351 }
1352 case Bytecodes::_lastore:
1353 {
1354 pop_long();
1355 pop_int();
1356 pop_typeArray();
1357 // assert here?
1358 break;
1359 }
1360 case Bytecodes::_lcmp:
1361 {
1362 pop_long();
1363 pop_long();
1364 push_int();
1365 break;
1366 }
1367 case Bytecodes::_lconst_0:
1368 case Bytecodes::_lconst_1:
1369 {
1370 push_long();
1371 break;
1372 }
1373 case Bytecodes::_ldc:
1374 case Bytecodes::_ldc_w:
1375 case Bytecodes::_ldc2_w:
1376 {
1377 do_ldc(str);
1378 break;
1379 }
1380
1381 case Bytecodes::_lload: load_local_long(str->get_index()); break;
1382 case Bytecodes::_lload_0: load_local_long(0); break;
1383 case Bytecodes::_lload_1: load_local_long(1); break;
1384 case Bytecodes::_lload_2: load_local_long(2); break;
1385 case Bytecodes::_lload_3: load_local_long(3); break;
1386
1387 case Bytecodes::_lneg:
1388 {
1389 pop_long();
1390 push_long();
1391 break;
1392 }
1393 case Bytecodes::_lreturn:
1394 {
1395 pop_long();
1396 break;
1397 }
1398 case Bytecodes::_lshl:
1399 case Bytecodes::_lshr:
1400 case Bytecodes::_lushr:
1401 {
1402 pop_int();
1403 pop_long();
1404 push_long();
1405 break;
1406 }
1407 case Bytecodes::_lstore: store_local_long(str->get_index()); break;
1408 case Bytecodes::_lstore_0: store_local_long(0); break;
1409 case Bytecodes::_lstore_1: store_local_long(1); break;
1410 case Bytecodes::_lstore_2: store_local_long(2); break;
1411 case Bytecodes::_lstore_3: store_local_long(3); break;
1412
1413 case Bytecodes::_multianewarray: do_multianewarray(str); break;
1414
1415 case Bytecodes::_new: do_new(str); break;
1416
1417 case Bytecodes::_newarray: do_newarray(str); break;
1418
1419 case Bytecodes::_pop:
1420 {
1421 pop();
1422 break;
1423 }
1424 case Bytecodes::_pop2:
1425 {
1426 pop();
1427 pop();
1428 break;
1429 }
1430
1431 case Bytecodes::_putfield: do_putfield(str); break;
1432 case Bytecodes::_putstatic: do_putstatic(str); break;
1433
1434 case Bytecodes::_ret: do_ret(str); break;
1435
1436 case Bytecodes::_swap:
1437 {
1438 ciType* value1 = pop_value();
1439 ciType* value2 = pop_value();
1440 push(value1);
1441 push(value2);
1442 break;
1443 }
1444 case Bytecodes::_wide:
1445 default:
1446 {
1447 // The iterator should skip this.
1448 ShouldNotReachHere();
1449 break;
1450 }
1451 }
1452
1453 if (CITraceTypeFlow) {
1454 print_on(tty);
1455 }
1456
1457 return (_trap_bci != -1);
1458 }
1459
1460 #ifndef PRODUCT
1461 // ------------------------------------------------------------------
1462 // ciTypeFlow::StateVector::print_cell_on
1463 void ciTypeFlow::StateVector::print_cell_on(outputStream* st, Cell c) const {
1464 ciType* type = type_at(c);
1465 if (type == top_type()) {
1466 st->print("top");
1467 } else if (type == bottom_type()) {
1468 st->print("bottom");
1469 } else if (type == null_type()) {
1470 st->print("null");
1471 } else if (type == long2_type()) {
1472 st->print("long2");
1473 } else if (type == double2_type()) {
1474 st->print("double2");
1475 } else if (is_int(type)) {
1476 st->print("int");
1477 } else if (is_long(type)) {
1478 st->print("long");
1479 } else if (is_float(type)) {
1480 st->print("float");
1481 } else if (is_double(type)) {
1482 st->print("double");
1483 } else if (type->is_return_address()) {
1484 st->print("address(%d)", type->as_return_address()->bci());
1485 } else {
1486 if (type->is_klass()) {
1487 type->as_klass()->name()->print_symbol_on(st);
1488 } else {
1489 st->print("UNEXPECTED TYPE");
1490 type->print();
1491 }
1492 }
1493 }
1494
1495 // ------------------------------------------------------------------
1496 // ciTypeFlow::StateVector::print_on
1497 void ciTypeFlow::StateVector::print_on(outputStream* st) const {
1498 int num_locals = _outer->max_locals();
1499 int num_stack = stack_size();
1500 int num_monitors = monitor_count();
1501 st->print_cr(" State : locals %d, stack %d, monitors %d", num_locals, num_stack, num_monitors);
1502 if (num_stack >= 0) {
1503 int i;
1504 for (i = 0; i < num_locals; i++) {
1505 st->print(" local %2d : ", i);
1506 print_cell_on(st, local(i));
1507 st->cr();
1508 }
1509 for (i = 0; i < num_stack; i++) {
1510 st->print(" stack %2d : ", i);
1511 print_cell_on(st, stack(i));
1512 st->cr();
1513 }
1514 }
1515 }
1516 #endif
1517
1518
1519 // ------------------------------------------------------------------
1520 // ciTypeFlow::SuccIter::next
1521 //
1522 void ciTypeFlow::SuccIter::next() {
1523 int succ_ct = _pred->successors()->length();
1524 int next = _index + 1;
1525 if (next < succ_ct) {
1526 _index = next;
1527 _succ = _pred->successors()->at(next);
1528 return;
1529 }
1530 for (int i = next - succ_ct; i < _pred->exceptions()->length(); i++) {
1531 // Do not compile any code for unloaded exception types.
1532 // Following compiler passes are responsible for doing this also.
1533 ciInstanceKlass* exception_klass = _pred->exc_klasses()->at(i);
1534 if (exception_klass->is_loaded()) {
1535 _index = next;
1536 _succ = _pred->exceptions()->at(i);
1537 return;
1538 }
1539 next++;
1540 }
1541 _index = -1;
1542 _succ = NULL;
1543 }
1544
1545 // ------------------------------------------------------------------
1546 // ciTypeFlow::SuccIter::set_succ
1547 //
1548 void ciTypeFlow::SuccIter::set_succ(Block* succ) {
1549 int succ_ct = _pred->successors()->length();
1550 if (_index < succ_ct) {
1551 _pred->successors()->at_put(_index, succ);
1552 } else {
1553 int idx = _index - succ_ct;
1554 _pred->exceptions()->at_put(idx, succ);
1555 }
1556 }
1557
1558 // ciTypeFlow::Block
1559 //
1560 // A basic block.
1561
1562 // ------------------------------------------------------------------
1563 // ciTypeFlow::Block::Block
1564 ciTypeFlow::Block::Block(ciTypeFlow* outer,
1565 ciBlock *ciblk,
1566 ciTypeFlow::JsrSet* jsrs) {
1567 _ciblock = ciblk;
1568 _exceptions = NULL;
1569 _exc_klasses = NULL;
1570 _successors = NULL;
1571 _state = new (outer->arena()) StateVector(outer);
1572 JsrSet* new_jsrs =
1573 new (outer->arena()) JsrSet(outer->arena(), jsrs->size());
1574 jsrs->copy_into(new_jsrs);
1575 _jsrs = new_jsrs;
1576 _next = NULL;
1577 _on_work_list = false;
1578 _backedge_copy = false;
1579 _exception_entry = false;
1580 _trap_bci = -1;
1581 _trap_index = 0;
1582 df_init();
1583
1584 if (CITraceTypeFlow) {
1585 tty->print_cr(">> Created new block");
1586 print_on(tty);
1587 }
1588
1589 assert(this->outer() == outer, "outer link set up");
1590 assert(!outer->have_block_count(), "must not have mapped blocks yet");
1591 }
1592
1593 // ------------------------------------------------------------------
1594 // ciTypeFlow::Block::df_init
1595 void ciTypeFlow::Block::df_init() {
1596 _pre_order = -1; assert(!has_pre_order(), "");
1597 _post_order = -1; assert(!has_post_order(), "");
1598 _loop = NULL;
1599 _irreducible_entry = false;
1600 _rpo_next = NULL;
1601 }
1602
1603 // ------------------------------------------------------------------
1604 // ciTypeFlow::Block::successors
1605 //
1606 // Get the successors for this Block.
1607 GrowableArray<ciTypeFlow::Block*>*
1608 ciTypeFlow::Block::successors(ciBytecodeStream* str,
1609 ciTypeFlow::StateVector* state,
1610 ciTypeFlow::JsrSet* jsrs) {
1611 if (_successors == NULL) {
1612 if (CITraceTypeFlow) {
1613 tty->print(">> Computing successors for block ");
1614 print_value_on(tty);
1615 tty->cr();
1616 }
1617
1618 ciTypeFlow* analyzer = outer();
1619 Arena* arena = analyzer->arena();
1620 Block* block = NULL;
1621 bool has_successor = !has_trap() &&
1622 (control() != ciBlock::fall_through_bci || limit() < analyzer->code_size());
1623 if (!has_successor) {
1624 _successors =
1625 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1626 // No successors
1627 } else if (control() == ciBlock::fall_through_bci) {
1628 assert(str->cur_bci() == limit(), "bad block end");
1629 // This block simply falls through to the next.
1630 _successors =
1631 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1632
1633 Block* block = analyzer->block_at(limit(), _jsrs);
1634 assert(_successors->length() == FALL_THROUGH, "");
1635 _successors->append(block);
1636 } else {
1637 int current_bci = str->cur_bci();
1638 int next_bci = str->next_bci();
1639 int branch_bci = -1;
1640 Block* target = NULL;
1641 assert(str->next_bci() == limit(), "bad block end");
1642 // This block is not a simple fall-though. Interpret
1643 // the current bytecode to find our successors.
1644 switch (str->cur_bc()) {
1645 case Bytecodes::_ifeq: case Bytecodes::_ifne:
1646 case Bytecodes::_iflt: case Bytecodes::_ifge:
1647 case Bytecodes::_ifgt: case Bytecodes::_ifle:
1648 case Bytecodes::_if_icmpeq: case Bytecodes::_if_icmpne:
1649 case Bytecodes::_if_icmplt: case Bytecodes::_if_icmpge:
1650 case Bytecodes::_if_icmpgt: case Bytecodes::_if_icmple:
1651 case Bytecodes::_if_acmpeq: case Bytecodes::_if_acmpne:
1652 case Bytecodes::_ifnull: case Bytecodes::_ifnonnull:
1653 // Our successors are the branch target and the next bci.
1654 branch_bci = str->get_dest();
1655 _successors =
1656 new (arena) GrowableArray<Block*>(arena, 2, 0, NULL);
1657 assert(_successors->length() == IF_NOT_TAKEN, "");
1658 _successors->append(analyzer->block_at(next_bci, jsrs));
1659 assert(_successors->length() == IF_TAKEN, "");
1660 _successors->append(analyzer->block_at(branch_bci, jsrs));
1661 break;
1662
1663 case Bytecodes::_goto:
1664 branch_bci = str->get_dest();
1665 _successors =
1666 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1667 assert(_successors->length() == GOTO_TARGET, "");
1668 _successors->append(analyzer->block_at(branch_bci, jsrs));
1669 break;
1670
1671 case Bytecodes::_jsr:
1672 branch_bci = str->get_dest();
1673 _successors =
1674 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1675 assert(_successors->length() == GOTO_TARGET, "");
1676 _successors->append(analyzer->block_at(branch_bci, jsrs));
1677 break;
1678
1679 case Bytecodes::_goto_w:
1680 case Bytecodes::_jsr_w:
1681 _successors =
1682 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1683 assert(_successors->length() == GOTO_TARGET, "");
1684 _successors->append(analyzer->block_at(str->get_far_dest(), jsrs));
1685 break;
1686
1687 case Bytecodes::_tableswitch: {
1688 Bytecode_tableswitch *tableswitch =
1689 Bytecode_tableswitch_at(str->cur_bcp());
1690
1691 int len = tableswitch->length();
1692 _successors =
1693 new (arena) GrowableArray<Block*>(arena, len+1, 0, NULL);
1694 int bci = current_bci + tableswitch->default_offset();
1695 Block* block = analyzer->block_at(bci, jsrs);
1696 assert(_successors->length() == SWITCH_DEFAULT, "");
1697 _successors->append(block);
1698 while (--len >= 0) {
1699 int bci = current_bci + tableswitch->dest_offset_at(len);
1700 block = analyzer->block_at(bci, jsrs);
1701 assert(_successors->length() >= SWITCH_CASES, "");
1702 _successors->append_if_missing(block);
1703 }
1704 break;
1705 }
1706
1707 case Bytecodes::_lookupswitch: {
1708 Bytecode_lookupswitch *lookupswitch =
1709 Bytecode_lookupswitch_at(str->cur_bcp());
1710
1711 int npairs = lookupswitch->number_of_pairs();
1712 _successors =
1713 new (arena) GrowableArray<Block*>(arena, npairs+1, 0, NULL);
1714 int bci = current_bci + lookupswitch->default_offset();
1715 Block* block = analyzer->block_at(bci, jsrs);
1716 assert(_successors->length() == SWITCH_DEFAULT, "");
1717 _successors->append(block);
1718 while(--npairs >= 0) {
1719 LookupswitchPair *pair = lookupswitch->pair_at(npairs);
1720 int bci = current_bci + pair->offset();
1721 Block* block = analyzer->block_at(bci, jsrs);
1722 assert(_successors->length() >= SWITCH_CASES, "");
1723 _successors->append_if_missing(block);
1724 }
1725 break;
1726 }
1727
1728 case Bytecodes::_athrow: case Bytecodes::_ireturn:
1729 case Bytecodes::_lreturn: case Bytecodes::_freturn:
1730 case Bytecodes::_dreturn: case Bytecodes::_areturn:
1731 case Bytecodes::_return:
1732 _successors =
1733 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1734 // No successors
1735 break;
1736
1737 case Bytecodes::_ret: {
1738 _successors =
1739 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1740
1741 Cell local = state->local(str->get_index());
1742 ciType* return_address = state->type_at(local);
1743 assert(return_address->is_return_address(), "verify: wrong type");
1744 int bci = return_address->as_return_address()->bci();
1745 assert(_successors->length() == GOTO_TARGET, "");
1746 _successors->append(analyzer->block_at(bci, jsrs));
1747 break;
1748 }
1749
1750 case Bytecodes::_wide:
1751 default:
1752 ShouldNotReachHere();
1753 break;
1754 }
1755 }
1756 }
1757 return _successors;
1758 }
1759
1760 // ------------------------------------------------------------------
1761 // ciTypeFlow::Block:compute_exceptions
1762 //
1763 // Compute the exceptional successors and types for this Block.
1764 void ciTypeFlow::Block::compute_exceptions() {
1765 assert(_exceptions == NULL && _exc_klasses == NULL, "repeat");
1766
1767 if (CITraceTypeFlow) {
1768 tty->print(">> Computing exceptions for block ");
1769 print_value_on(tty);
1770 tty->cr();
1771 }
1772
1773 ciTypeFlow* analyzer = outer();
1774 Arena* arena = analyzer->arena();
1775
1776 // Any bci in the block will do.
1777 ciExceptionHandlerStream str(analyzer->method(), start());
1778
1779 // Allocate our growable arrays.
1780 int exc_count = str.count();
1781 _exceptions = new (arena) GrowableArray<Block*>(arena, exc_count, 0, NULL);
1782 _exc_klasses = new (arena) GrowableArray<ciInstanceKlass*>(arena, exc_count,
1783 0, NULL);
1784
1785 for ( ; !str.is_done(); str.next()) {
1786 ciExceptionHandler* handler = str.handler();
1787 int bci = handler->handler_bci();
1788 ciInstanceKlass* klass = NULL;
1789 if (bci == -1) {
1790 // There is no catch all. It is possible to exit the method.
1791 break;
1792 }
1793 if (handler->is_catch_all()) {
1794 klass = analyzer->env()->Throwable_klass();
1795 } else {
1796 klass = handler->catch_klass();
1797 }
1798 _exceptions->append(analyzer->block_at(bci, _jsrs));
1799 _exc_klasses->append(klass);
1800 }
1801 }
1802
1803 // ------------------------------------------------------------------
1804 // ciTypeFlow::Block::set_backedge_copy
1805 // Use this only to make a pre-existing public block into a backedge copy.
1806 void ciTypeFlow::Block::set_backedge_copy(bool z) {
1807 assert(z || (z == is_backedge_copy()), "cannot make a backedge copy public");
1808 _backedge_copy = z;
1809 }
1810
1811 // ------------------------------------------------------------------
1812 // ciTypeFlow::Block::is_clonable_exit
1813 //
1814 // At most 2 normal successors, one of which continues looping,
1815 // and all exceptional successors must exit.
1816 bool ciTypeFlow::Block::is_clonable_exit(ciTypeFlow::Loop* lp) {
1817 int normal_cnt = 0;
1818 int in_loop_cnt = 0;
1819 for (SuccIter iter(this); !iter.done(); iter.next()) {
1820 Block* succ = iter.succ();
1821 if (iter.is_normal_ctrl()) {
1822 if (++normal_cnt > 2) return false;
1823 if (lp->contains(succ->loop())) {
1824 if (++in_loop_cnt > 1) return false;
1825 }
1826 } else {
1827 if (lp->contains(succ->loop())) return false;
1828 }
1829 }
1830 return in_loop_cnt == 1;
1831 }
1832
1833 // ------------------------------------------------------------------
1834 // ciTypeFlow::Block::looping_succ
1835 //
1836 ciTypeFlow::Block* ciTypeFlow::Block::looping_succ(ciTypeFlow::Loop* lp) {
1837 assert(successors()->length() <= 2, "at most 2 normal successors");
1838 for (SuccIter iter(this); !iter.done(); iter.next()) {
1839 Block* succ = iter.succ();
1840 if (lp->contains(succ->loop())) {
1841 return succ;
1842 }
1843 }
1844 return NULL;
1845 }
1846
1847 #ifndef PRODUCT
1848 // ------------------------------------------------------------------
1849 // ciTypeFlow::Block::print_value_on
1850 void ciTypeFlow::Block::print_value_on(outputStream* st) const {
1851 if (has_pre_order()) st->print("#%-2d ", pre_order());
1852 if (has_rpo()) st->print("rpo#%-2d ", rpo());
1853 st->print("[%d - %d)", start(), limit());
1854 if (is_loop_head()) st->print(" lphd");
1855 if (is_irreducible_entry()) st->print(" irred");
1856 if (_jsrs->size() > 0) { st->print("/"); _jsrs->print_on(st); }
1857 if (is_backedge_copy()) st->print("/backedge_copy");
1858 }
1859
1860 // ------------------------------------------------------------------
1861 // ciTypeFlow::Block::print_on
1862 void ciTypeFlow::Block::print_on(outputStream* st) const {
1863 if ((Verbose || WizardMode)) {
1864 outer()->method()->print_codes_on(start(), limit(), st);
1865 }
1866 st->print_cr(" ==================================================== ");
1867 st->print (" ");
1868 print_value_on(st);
1869 st->print(" Stored locals: "); def_locals()->print_on(st, outer()->method()->max_locals()); tty->cr();
1870 if (loop() && loop()->parent() != NULL) {
1871 st->print(" loops:");
1872 Loop* lp = loop();
1873 do {
1874 st->print(" %d<-%d", lp->head()->pre_order(),lp->tail()->pre_order());
1875 if (lp->is_irreducible()) st->print("(ir)");
1876 lp = lp->parent();
1877 } while (lp->parent() != NULL);
1878 }
1879 st->cr();
1880 _state->print_on(st);
1881 if (_successors == NULL) {
1882 st->print_cr(" No successor information");
1883 } else {
1884 int num_successors = _successors->length();
1885 st->print_cr(" Successors : %d", num_successors);
1886 for (int i = 0; i < num_successors; i++) {
1887 Block* successor = _successors->at(i);
1888 st->print(" ");
1889 successor->print_value_on(st);
1890 st->cr();
1891 }
1892 }
1893 if (_exceptions == NULL) {
1894 st->print_cr(" No exception information");
1895 } else {
1896 int num_exceptions = _exceptions->length();
1897 st->print_cr(" Exceptions : %d", num_exceptions);
1898 for (int i = 0; i < num_exceptions; i++) {
1899 Block* exc_succ = _exceptions->at(i);
1900 ciInstanceKlass* exc_klass = _exc_klasses->at(i);
1901 st->print(" ");
1902 exc_succ->print_value_on(st);
1903 st->print(" -- ");
1904 exc_klass->name()->print_symbol_on(st);
1905 st->cr();
1906 }
1907 }
1908 if (has_trap()) {
1909 st->print_cr(" Traps on %d with trap index %d", trap_bci(), trap_index());
1910 }
1911 st->print_cr(" ==================================================== ");
1912 }
1913 #endif
1914
1915 #ifndef PRODUCT
1916 // ------------------------------------------------------------------
1917 // ciTypeFlow::LocalSet::print_on
1918 void ciTypeFlow::LocalSet::print_on(outputStream* st, int limit) const {
1919 st->print("{");
1920 for (int i = 0; i < max; i++) {
1921 if (test(i)) st->print(" %d", i);
1922 }
1923 if (limit > max) {
1924 st->print(" %d..%d ", max, limit);
1925 }
1926 st->print(" }");
1927 }
1928 #endif
1929
1930 // ciTypeFlow
1931 //
1932 // This is a pass over the bytecodes which computes the following:
1933 // basic block structure
1934 // interpreter type-states (a la the verifier)
1935
1936 // ------------------------------------------------------------------
1937 // ciTypeFlow::ciTypeFlow
1938 ciTypeFlow::ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci) {
1939 _env = env;
1940 _method = method;
1941 _methodBlocks = method->get_method_blocks();
1942 _max_locals = method->max_locals();
1943 _max_stack = method->max_stack();
1944 _code_size = method->code_size();
1945 _has_irreducible_entry = false;
1946 _osr_bci = osr_bci;
1947 _failure_reason = NULL;
1948 assert(0 <= start_bci() && start_bci() < code_size() , err_msg("correct osr_bci argument: 0 <= %d < %d", start_bci(), code_size()));
1949 _work_list = NULL;
1950
1951 _ciblock_count = _methodBlocks->num_blocks();
1952 _idx_to_blocklist = NEW_ARENA_ARRAY(arena(), GrowableArray<Block*>*, _ciblock_count);
1953 for (int i = 0; i < _ciblock_count; i++) {
1954 _idx_to_blocklist[i] = NULL;
1955 }
1956 _block_map = NULL; // until all blocks are seen
1957 _jsr_count = 0;
1958 _jsr_records = NULL;
1959 }
1960
1961 // ------------------------------------------------------------------
1962 // ciTypeFlow::work_list_next
1963 //
1964 // Get the next basic block from our work list.
1965 ciTypeFlow::Block* ciTypeFlow::work_list_next() {
1966 assert(!work_list_empty(), "work list must not be empty");
1967 Block* next_block = _work_list;
1968 _work_list = next_block->next();
1969 next_block->set_next(NULL);
1970 next_block->set_on_work_list(false);
1971 return next_block;
1972 }
1973
1974 // ------------------------------------------------------------------
1975 // ciTypeFlow::add_to_work_list
1976 //
1977 // Add a basic block to our work list.
1978 // List is sorted by decreasing postorder sort (same as increasing RPO)
1979 void ciTypeFlow::add_to_work_list(ciTypeFlow::Block* block) {
1980 assert(!block->is_on_work_list(), "must not already be on work list");
1981
1982 if (CITraceTypeFlow) {
1983 tty->print(">> Adding block ");
1984 block->print_value_on(tty);
1985 tty->print_cr(" to the work list : ");
1986 }
1987
1988 block->set_on_work_list(true);
1989
1990 // decreasing post order sort
1991
1992 Block* prev = NULL;
1993 Block* current = _work_list;
1994 int po = block->post_order();
1995 while (current != NULL) {
1996 if (!current->has_post_order() || po > current->post_order())
1997 break;
1998 prev = current;
1999 current = current->next();
2000 }
2001 if (prev == NULL) {
2002 block->set_next(_work_list);
2003 _work_list = block;
2004 } else {
2005 block->set_next(current);
2006 prev->set_next(block);
2007 }
2008
2009 if (CITraceTypeFlow) {
2010 tty->cr();
2011 }
2012 }
2013
2014 // ------------------------------------------------------------------
2015 // ciTypeFlow::block_at
2016 //
2017 // Return the block beginning at bci which has a JsrSet compatible
2018 // with jsrs.
2019 ciTypeFlow::Block* ciTypeFlow::block_at(int bci, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
2020 // First find the right ciBlock.
2021 if (CITraceTypeFlow) {
2022 tty->print(">> Requesting block for %d/", bci);
2023 jsrs->print_on(tty);
2024 tty->cr();
2025 }
2026
2027 ciBlock* ciblk = _methodBlocks->block_containing(bci);
2028 assert(ciblk->start_bci() == bci, "bad ciBlock boundaries");
2029 Block* block = get_block_for(ciblk->index(), jsrs, option);
2030
2031 assert(block == NULL? (option == no_create): block->is_backedge_copy() == (option == create_backedge_copy), "create option consistent with result");
2032
2033 if (CITraceTypeFlow) {
2034 if (block != NULL) {
2035 tty->print(">> Found block ");
2036 block->print_value_on(tty);
2037 tty->cr();
2038 } else {
2039 tty->print_cr(">> No such block.");
2040 }
2041 }
2042
2043 return block;
2044 }
2045
2046 // ------------------------------------------------------------------
2047 // ciTypeFlow::make_jsr_record
2048 //
2049 // Make a JsrRecord for a given (entry, return) pair, if such a record
2050 // does not already exist.
2051 ciTypeFlow::JsrRecord* ciTypeFlow::make_jsr_record(int entry_address,
2052 int return_address) {
2053 if (_jsr_records == NULL) {
2054 _jsr_records = new (arena()) GrowableArray<JsrRecord*>(arena(),
2055 _jsr_count,
2056 0,
2057 NULL);
2058 }
2059 JsrRecord* record = NULL;
2060 int len = _jsr_records->length();
2061 for (int i = 0; i < len; i++) {
2062 JsrRecord* record = _jsr_records->at(i);
2063 if (record->entry_address() == entry_address &&
2064 record->return_address() == return_address) {
2065 return record;
2066 }
2067 }
2068
2069 record = new (arena()) JsrRecord(entry_address, return_address);
2070 _jsr_records->append(record);
2071 return record;
2072 }
2073
2074 // ------------------------------------------------------------------
2075 // ciTypeFlow::flow_exceptions
2076 //
2077 // Merge the current state into all exceptional successors at the
2078 // current point in the code.
2079 void ciTypeFlow::flow_exceptions(GrowableArray<ciTypeFlow::Block*>* exceptions,
2080 GrowableArray<ciInstanceKlass*>* exc_klasses,
2081 ciTypeFlow::StateVector* state) {
2082 int len = exceptions->length();
2083 assert(exc_klasses->length() == len, "must have same length");
2084 for (int i = 0; i < len; i++) {
2085 Block* block = exceptions->at(i);
2086 ciInstanceKlass* exception_klass = exc_klasses->at(i);
2087
2088 if (!exception_klass->is_loaded()) {
2089 // Do not compile any code for unloaded exception types.
2090 // Following compiler passes are responsible for doing this also.
2091 continue;
2092 }
2093
2094 if (block->meet_exception(exception_klass, state)) {
2095 // Block was modified and has PO. Add it to the work list.
2096 if (block->has_post_order() &&
2097 !block->is_on_work_list()) {
2098 add_to_work_list(block);
2099 }
2100 }
2101 }
2102 }
2103
2104 // ------------------------------------------------------------------
2105 // ciTypeFlow::flow_successors
2106 //
2107 // Merge the current state into all successors at the current point
2108 // in the code.
2109 void ciTypeFlow::flow_successors(GrowableArray<ciTypeFlow::Block*>* successors,
2110 ciTypeFlow::StateVector* state) {
2111 int len = successors->length();
2112 for (int i = 0; i < len; i++) {
2113 Block* block = successors->at(i);
2114 if (block->meet(state)) {
2115 // Block was modified and has PO. Add it to the work list.
2116 if (block->has_post_order() &&
2117 !block->is_on_work_list()) {
2118 add_to_work_list(block);
2119 }
2120 }
2121 }
2122 }
2123
2124 // ------------------------------------------------------------------
2125 // ciTypeFlow::can_trap
2126 //
2127 // Tells if a given instruction is able to generate an exception edge.
2128 bool ciTypeFlow::can_trap(ciBytecodeStream& str) {
2129 // Cf. GenerateOopMap::do_exception_edge.
2130 if (!Bytecodes::can_trap(str.cur_bc())) return false;
2131
2132 switch (str.cur_bc()) {
2133 // %%% FIXME: ldc of Class can generate an exception
2134 case Bytecodes::_ldc:
2135 case Bytecodes::_ldc_w:
2136 case Bytecodes::_ldc2_w:
2137 case Bytecodes::_aload_0:
2138 // These bytecodes can trap for rewriting. We need to assume that
2139 // they do not throw exceptions to make the monitor analysis work.
2140 return false;
2141
2142 case Bytecodes::_ireturn:
2143 case Bytecodes::_lreturn:
2144 case Bytecodes::_freturn:
2145 case Bytecodes::_dreturn:
2146 case Bytecodes::_areturn:
2147 case Bytecodes::_return:
2148 // We can assume the monitor stack is empty in this analysis.
2149 return false;
2150
2151 case Bytecodes::_monitorexit:
2152 // We can assume monitors are matched in this analysis.
2153 return false;
2154 }
2155
2156 return true;
2157 }
2158
2159 // ------------------------------------------------------------------
2160 // ciTypeFlow::clone_loop_heads
2161 //
2162 // Clone the loop heads
2163 bool ciTypeFlow::clone_loop_heads(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) {
2164 bool rslt = false;
2165 for (PreorderLoops iter(loop_tree_root()); !iter.done(); iter.next()) {
2166 lp = iter.current();
2167 Block* head = lp->head();
2168 if (lp == loop_tree_root() ||
2169 lp->is_irreducible() ||
2170 !head->is_clonable_exit(lp))
2171 continue;
2172
2173 // check not already cloned
2174 if (head->backedge_copy_count() != 0)
2175 continue;
2176
2177 // check _no_ shared head below us
2178 Loop* ch;
2179 for (ch = lp->child(); ch != NULL && ch->head() != head; ch = ch->sibling());
2180 if (ch != NULL)
2181 continue;
2182
2183 // Clone head
2184 Block* new_head = head->looping_succ(lp);
2185 Block* clone = clone_loop_head(lp, temp_vector, temp_set);
2186 // Update lp's info
2187 clone->set_loop(lp);
2188 lp->set_head(new_head);
2189 lp->set_tail(clone);
2190 // And move original head into outer loop
2191 head->set_loop(lp->parent());
2192
2193 rslt = true;
2194 }
2195 return rslt;
2196 }
2197
2198 // ------------------------------------------------------------------
2199 // ciTypeFlow::clone_loop_head
2200 //
2201 // Clone lp's head and replace tail's successors with clone.
2202 //
2203 // |
2204 // v
2205 // head <-> body
2206 // |
2207 // v
2208 // exit
2209 //
2210 // new_head
2211 //
2212 // |
2213 // v
2214 // head ----------\
2215 // | |
2216 // | v
2217 // | clone <-> body
2218 // | |
2219 // | /--/
2220 // | |
2221 // v v
2222 // exit
2223 //
2224 ciTypeFlow::Block* ciTypeFlow::clone_loop_head(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) {
2225 Block* head = lp->head();
2226 Block* tail = lp->tail();
2227 if (CITraceTypeFlow) {
2228 tty->print(">> Requesting clone of loop head "); head->print_value_on(tty);
2229 tty->print(" for predecessor "); tail->print_value_on(tty);
2230 tty->cr();
2231 }
2232 Block* clone = block_at(head->start(), head->jsrs(), create_backedge_copy);
2233 assert(clone->backedge_copy_count() == 1, "one backedge copy for all back edges");
2234
2235 assert(!clone->has_pre_order(), "just created");
2236 clone->set_next_pre_order();
2237
2238 // Insert clone after (orig) tail in reverse post order
2239 clone->set_rpo_next(tail->rpo_next());
2240 tail->set_rpo_next(clone);
2241
2242 // tail->head becomes tail->clone
2243 for (SuccIter iter(tail); !iter.done(); iter.next()) {
2244 if (iter.succ() == head) {
2245 iter.set_succ(clone);
2246 }
2247 }
2248 flow_block(tail, temp_vector, temp_set);
2249 if (head == tail) {
2250 // For self-loops, clone->head becomes clone->clone
2251 flow_block(clone, temp_vector, temp_set);
2252 for (SuccIter iter(clone); !iter.done(); iter.next()) {
2253 if (iter.succ() == head) {
2254 iter.set_succ(clone);
2255 break;
2256 }
2257 }
2258 }
2259 flow_block(clone, temp_vector, temp_set);
2260
2261 return clone;
2262 }
2263
2264 // ------------------------------------------------------------------
2265 // ciTypeFlow::flow_block
2266 //
2267 // Interpret the effects of the bytecodes on the incoming state
2268 // vector of a basic block. Push the changed state to succeeding
2269 // basic blocks.
2270 void ciTypeFlow::flow_block(ciTypeFlow::Block* block,
2271 ciTypeFlow::StateVector* state,
2272 ciTypeFlow::JsrSet* jsrs) {
2273 if (CITraceTypeFlow) {
2274 tty->print("\n>> ANALYZING BLOCK : ");
2275 tty->cr();
2276 block->print_on(tty);
2277 }
2278 assert(block->has_pre_order(), "pre-order is assigned before 1st flow");
2279
2280 int start = block->start();
2281 int limit = block->limit();
2282 int control = block->control();
2283 if (control != ciBlock::fall_through_bci) {
2284 limit = control;
2285 }
2286
2287 // Grab the state from the current block.
2288 block->copy_state_into(state);
2289 state->def_locals()->clear();
2290
2291 GrowableArray<Block*>* exceptions = block->exceptions();
2292 GrowableArray<ciInstanceKlass*>* exc_klasses = block->exc_klasses();
2293 bool has_exceptions = exceptions->length() > 0;
2294
2295 bool exceptions_used = false;
2296
2297 ciBytecodeStream str(method());
2298 str.reset_to_bci(start);
2299 Bytecodes::Code code;
2300 while ((code = str.next()) != ciBytecodeStream::EOBC() &&
2301 str.cur_bci() < limit) {
2302 // Check for exceptional control flow from this point.
2303 if (has_exceptions && can_trap(str)) {
2304 flow_exceptions(exceptions, exc_klasses, state);
2305 exceptions_used = true;
2306 }
2307 // Apply the effects of the current bytecode to our state.
2308 bool res = state->apply_one_bytecode(&str);
2309
2310 // Watch for bailouts.
2311 if (failing()) return;
2312
2313 if (res) {
2314
2315 // We have encountered a trap. Record it in this block.
2316 block->set_trap(state->trap_bci(), state->trap_index());
2317
2318 if (CITraceTypeFlow) {
2319 tty->print_cr(">> Found trap");
2320 block->print_on(tty);
2321 }
2322
2323 // Save set of locals defined in this block
2324 block->def_locals()->add(state->def_locals());
2325
2326 // Record (no) successors.
2327 block->successors(&str, state, jsrs);
2328
2329 assert(!has_exceptions || exceptions_used, "Not removing exceptions");
2330
2331 // Discontinue interpretation of this Block.
2332 return;
2333 }
2334 }
2335
2336 GrowableArray<Block*>* successors = NULL;
2337 if (control != ciBlock::fall_through_bci) {
2338 // Check for exceptional control flow from this point.
2339 if (has_exceptions && can_trap(str)) {
2340 flow_exceptions(exceptions, exc_klasses, state);
2341 exceptions_used = true;
2342 }
2343
2344 // Fix the JsrSet to reflect effect of the bytecode.
2345 block->copy_jsrs_into(jsrs);
2346 jsrs->apply_control(this, &str, state);
2347
2348 // Find successor edges based on old state and new JsrSet.
2349 successors = block->successors(&str, state, jsrs);
2350
2351 // Apply the control changes to the state.
2352 state->apply_one_bytecode(&str);
2353 } else {
2354 // Fall through control
2355 successors = block->successors(&str, NULL, NULL);
2356 }
2357
2358 // Save set of locals defined in this block
2359 block->def_locals()->add(state->def_locals());
2360
2361 // Remove untaken exception paths
2362 if (!exceptions_used)
2363 exceptions->clear();
2364
2365 // Pass our state to successors.
2366 flow_successors(successors, state);
2367 }
2368
2369 // ------------------------------------------------------------------
2370 // ciTypeFlow::PostOrderLoops::next
2371 //
2372 // Advance to next loop tree using a postorder, left-to-right traversal.
2373 void ciTypeFlow::PostorderLoops::next() {
2374 assert(!done(), "must not be done.");
2375 if (_current->sibling() != NULL) {
2376 _current = _current->sibling();
2377 while (_current->child() != NULL) {
2378 _current = _current->child();
2379 }
2380 } else {
2381 _current = _current->parent();
2382 }
2383 }
2384
2385 // ------------------------------------------------------------------
2386 // ciTypeFlow::PreOrderLoops::next
2387 //
2388 // Advance to next loop tree using a preorder, left-to-right traversal.
2389 void ciTypeFlow::PreorderLoops::next() {
2390 assert(!done(), "must not be done.");
2391 if (_current->child() != NULL) {
2392 _current = _current->child();
2393 } else if (_current->sibling() != NULL) {
2394 _current = _current->sibling();
2395 } else {
2396 while (_current != _root && _current->sibling() == NULL) {
2397 _current = _current->parent();
2398 }
2399 if (_current == _root) {
2400 _current = NULL;
2401 assert(done(), "must be done.");
2402 } else {
2403 assert(_current->sibling() != NULL, "must be more to do");
2404 _current = _current->sibling();
2405 }
2406 }
2407 }
2408
2409 // ------------------------------------------------------------------
2410 // ciTypeFlow::Loop::sorted_merge
2411 //
2412 // Merge the branch lp into this branch, sorting on the loop head
2413 // pre_orders. Returns the leaf of the merged branch.
2414 // Child and sibling pointers will be setup later.
2415 // Sort is (looking from leaf towards the root)
2416 // descending on primary key: loop head's pre_order, and
2417 // ascending on secondary key: loop tail's pre_order.
2418 ciTypeFlow::Loop* ciTypeFlow::Loop::sorted_merge(Loop* lp) {
2419 Loop* leaf = this;
2420 Loop* prev = NULL;
2421 Loop* current = leaf;
2422 while (lp != NULL) {
2423 int lp_pre_order = lp->head()->pre_order();
2424 // Find insertion point for "lp"
2425 while (current != NULL) {
2426 if (current == lp)
2427 return leaf; // Already in list
2428 if (current->head()->pre_order() < lp_pre_order)
2429 break;
2430 if (current->head()->pre_order() == lp_pre_order &&
2431 current->tail()->pre_order() > lp->tail()->pre_order()) {
2432 break;
2433 }
2434 prev = current;
2435 current = current->parent();
2436 }
2437 Loop* next_lp = lp->parent(); // Save future list of items to insert
2438 // Insert lp before current
2439 lp->set_parent(current);
2440 if (prev != NULL) {
2441 prev->set_parent(lp);
2442 } else {
2443 leaf = lp;
2444 }
2445 prev = lp; // Inserted item is new prev[ious]
2446 lp = next_lp; // Next item to insert
2447 }
2448 return leaf;
2449 }
2450
2451 // ------------------------------------------------------------------
2452 // ciTypeFlow::build_loop_tree
2453 //
2454 // Incrementally build loop tree.
2455 void ciTypeFlow::build_loop_tree(Block* blk) {
2456 assert(!blk->is_post_visited(), "precondition");
2457 Loop* innermost = NULL; // merge of loop tree branches over all successors
2458
2459 for (SuccIter iter(blk); !iter.done(); iter.next()) {
2460 Loop* lp = NULL;
2461 Block* succ = iter.succ();
2462 if (!succ->is_post_visited()) {
2463 // Found backedge since predecessor post visited, but successor is not
2464 assert(succ->pre_order() <= blk->pre_order(), "should be backedge");
2465
2466 // Create a LoopNode to mark this loop.
2467 lp = new (arena()) Loop(succ, blk);
2468 if (succ->loop() == NULL)
2469 succ->set_loop(lp);
2470 // succ->loop will be updated to innermost loop on a later call, when blk==succ
2471
2472 } else { // Nested loop
2473 lp = succ->loop();
2474
2475 // If succ is loop head, find outer loop.
2476 while (lp != NULL && lp->head() == succ) {
2477 lp = lp->parent();
2478 }
2479 if (lp == NULL) {
2480 // Infinite loop, it's parent is the root
2481 lp = loop_tree_root();
2482 }
2483 }
2484
2485 // Check for irreducible loop.
2486 // Successor has already been visited. If the successor's loop head
2487 // has already been post-visited, then this is another entry into the loop.
2488 while (lp->head()->is_post_visited() && lp != loop_tree_root()) {
2489 _has_irreducible_entry = true;
2490 lp->set_irreducible(succ);
2491 if (!succ->is_on_work_list()) {
2492 // Assume irreducible entries need more data flow
2493 add_to_work_list(succ);
2494 }
2495 Loop* plp = lp->parent();
2496 if (plp == NULL) {
2497 // This only happens for some irreducible cases. The parent
2498 // will be updated during a later pass.
2499 break;
2500 }
2501 lp = plp;
2502 }
2503
2504 // Merge loop tree branch for all successors.
2505 innermost = innermost == NULL ? lp : innermost->sorted_merge(lp);
2506
2507 } // end loop
2508
2509 if (innermost == NULL) {
2510 assert(blk->successors()->length() == 0, "CFG exit");
2511 blk->set_loop(loop_tree_root());
2512 } else if (innermost->head() == blk) {
2513 // If loop header, complete the tree pointers
2514 if (blk->loop() != innermost) {
2515 #if ASSERT
2516 assert(blk->loop()->head() == innermost->head(), "same head");
2517 Loop* dl;
2518 for (dl = innermost; dl != NULL && dl != blk->loop(); dl = dl->parent());
2519 assert(dl == blk->loop(), "blk->loop() already in innermost list");
2520 #endif
2521 blk->set_loop(innermost);
2522 }
2523 innermost->def_locals()->add(blk->def_locals());
2524 Loop* l = innermost;
2525 Loop* p = l->parent();
2526 while (p && l->head() == blk) {
2527 l->set_sibling(p->child()); // Put self on parents 'next child'
2528 p->set_child(l); // Make self the first child of parent
2529 p->def_locals()->add(l->def_locals());
2530 l = p; // Walk up the parent chain
2531 p = l->parent();
2532 }
2533 } else {
2534 blk->set_loop(innermost);
2535 innermost->def_locals()->add(blk->def_locals());
2536 }
2537 }
2538
2539 // ------------------------------------------------------------------
2540 // ciTypeFlow::Loop::contains
2541 //
2542 // Returns true if lp is nested loop.
2543 bool ciTypeFlow::Loop::contains(ciTypeFlow::Loop* lp) const {
2544 assert(lp != NULL, "");
2545 if (this == lp || head() == lp->head()) return true;
2546 int depth1 = depth();
2547 int depth2 = lp->depth();
2548 if (depth1 > depth2)
2549 return false;
2550 while (depth1 < depth2) {
2551 depth2--;
2552 lp = lp->parent();
2553 }
2554 return this == lp;
2555 }
2556
2557 // ------------------------------------------------------------------
2558 // ciTypeFlow::Loop::depth
2559 //
2560 // Loop depth
2561 int ciTypeFlow::Loop::depth() const {
2562 int dp = 0;
2563 for (Loop* lp = this->parent(); lp != NULL; lp = lp->parent())
2564 dp++;
2565 return dp;
2566 }
2567
2568 #ifndef PRODUCT
2569 // ------------------------------------------------------------------
2570 // ciTypeFlow::Loop::print
2571 void ciTypeFlow::Loop::print(outputStream* st, int indent) const {
2572 for (int i = 0; i < indent; i++) st->print(" ");
2573 st->print("%d<-%d %s",
2574 is_root() ? 0 : this->head()->pre_order(),
2575 is_root() ? 0 : this->tail()->pre_order(),
2576 is_irreducible()?" irr":"");
2577 st->print(" defs: ");
2578 def_locals()->print_on(st, _head->outer()->method()->max_locals());
2579 st->cr();
2580 for (Loop* ch = child(); ch != NULL; ch = ch->sibling())
2581 ch->print(st, indent+2);
2582 }
2583 #endif
2584
2585 // ------------------------------------------------------------------
2586 // ciTypeFlow::df_flow_types
2587 //
2588 // Perform the depth first type flow analysis. Helper for flow_types.
2589 void ciTypeFlow::df_flow_types(Block* start,
2590 bool do_flow,
2591 StateVector* temp_vector,
2592 JsrSet* temp_set) {
2593 int dft_len = 100;
2594 GrowableArray<Block*> stk(dft_len);
2595
2596 ciBlock* dummy = _methodBlocks->make_dummy_block();
2597 JsrSet* root_set = new JsrSet(NULL, 0);
2598 Block* root_head = new (arena()) Block(this, dummy, root_set);
2599 Block* root_tail = new (arena()) Block(this, dummy, root_set);
2600 root_head->set_pre_order(0);
2601 root_head->set_post_order(0);
2602 root_tail->set_pre_order(max_jint);
2603 root_tail->set_post_order(max_jint);
2604 set_loop_tree_root(new (arena()) Loop(root_head, root_tail));
2605
2606 stk.push(start);
2607
2608 _next_pre_order = 0; // initialize pre_order counter
2609 _rpo_list = NULL;
2610 int next_po = 0; // initialize post_order counter
2611
2612 // Compute RPO and the control flow graph
2613 int size;
2614 while ((size = stk.length()) > 0) {
2615 Block* blk = stk.top(); // Leave node on stack
2616 if (!blk->is_visited()) {
2617 // forward arc in graph
2618 assert (!blk->has_pre_order(), "");
2619 blk->set_next_pre_order();
2620
2621 if (_next_pre_order >= MaxNodeLimit / 2) {
2622 // Too many basic blocks. Bail out.
2623 // This can happen when try/finally constructs are nested to depth N,
2624 // and there is O(2**N) cloning of jsr bodies. See bug 4697245!
2625 // "MaxNodeLimit / 2" is used because probably the parser will
2626 // generate at least twice that many nodes and bail out.
2627 record_failure("too many basic blocks");
2628 return;
2629 }
2630 if (do_flow) {
2631 flow_block(blk, temp_vector, temp_set);
2632 if (failing()) return; // Watch for bailouts.
2633 }
2634 } else if (!blk->is_post_visited()) {
2635 // cross or back arc
2636 for (SuccIter iter(blk); !iter.done(); iter.next()) {
2637 Block* succ = iter.succ();
2638 if (!succ->is_visited()) {
2639 stk.push(succ);
2640 }
2641 }
2642 if (stk.length() == size) {
2643 // There were no additional children, post visit node now
2644 stk.pop(); // Remove node from stack
2645
2646 build_loop_tree(blk);
2647 blk->set_post_order(next_po++); // Assign post order
2648 prepend_to_rpo_list(blk);
2649 assert(blk->is_post_visited(), "");
2650
2651 if (blk->is_loop_head() && !blk->is_on_work_list()) {
2652 // Assume loop heads need more data flow
2653 add_to_work_list(blk);
2654 }
2655 }
2656 } else {
2657 stk.pop(); // Remove post-visited node from stack
2658 }
2659 }
2660 }
2661
2662 // ------------------------------------------------------------------
2663 // ciTypeFlow::flow_types
2664 //
2665 // Perform the type flow analysis, creating and cloning Blocks as
2666 // necessary.
2667 void ciTypeFlow::flow_types() {
2668 ResourceMark rm;
2669 StateVector* temp_vector = new StateVector(this);
2670 JsrSet* temp_set = new JsrSet(NULL, 16);
2671
2672 // Create the method entry block.
2673 Block* start = block_at(start_bci(), temp_set);
2674
2675 // Load the initial state into it.
2676 const StateVector* start_state = get_start_state();
2677 if (failing()) return;
2678 start->meet(start_state);
2679
2680 // Depth first visit
2681 df_flow_types(start, true /*do flow*/, temp_vector, temp_set);
2682
2683 if (failing()) return;
2684 assert(_rpo_list == start, "must be start");
2685
2686 // Any loops found?
2687 if (loop_tree_root()->child() != NULL &&
2688 env()->comp_level() >= CompLevel_full_optimization) {
2689 // Loop optimizations are not performed on Tier1 compiles.
2690
2691 bool changed = clone_loop_heads(loop_tree_root(), temp_vector, temp_set);
2692
2693 // If some loop heads were cloned, recompute postorder and loop tree
2694 if (changed) {
2695 loop_tree_root()->set_child(NULL);
2696 for (Block* blk = _rpo_list; blk != NULL;) {
2697 Block* next = blk->rpo_next();
2698 blk->df_init();
2699 blk = next;
2700 }
2701 df_flow_types(start, false /*no flow*/, temp_vector, temp_set);
2702 }
2703 }
2704
2705 if (CITraceTypeFlow) {
2706 tty->print_cr("\nLoop tree");
2707 loop_tree_root()->print();
2708 }
2709
2710 // Continue flow analysis until fixed point reached
2711
2712 debug_only(int max_block = _next_pre_order;)
2713
2714 while (!work_list_empty()) {
2715 Block* blk = work_list_next();
2716 assert (blk->has_post_order(), "post order assigned above");
2717
2718 flow_block(blk, temp_vector, temp_set);
2719
2720 assert (max_block == _next_pre_order, "no new blocks");
2721 assert (!failing(), "no more bailouts");
2722 }
2723 }
2724
2725 // ------------------------------------------------------------------
2726 // ciTypeFlow::map_blocks
2727 //
2728 // Create the block map, which indexes blocks in reverse post-order.
2729 void ciTypeFlow::map_blocks() {
2730 assert(_block_map == NULL, "single initialization");
2731 int block_ct = _next_pre_order;
2732 _block_map = NEW_ARENA_ARRAY(arena(), Block*, block_ct);
2733 assert(block_ct == block_count(), "");
2734
2735 Block* blk = _rpo_list;
2736 for (int m = 0; m < block_ct; m++) {
2737 int rpo = blk->rpo();
2738 assert(rpo == m, "should be sequential");
2739 _block_map[rpo] = blk;
2740 blk = blk->rpo_next();
2741 }
2742 assert(blk == NULL, "should be done");
2743
2744 for (int j = 0; j < block_ct; j++) {
2745 assert(_block_map[j] != NULL, "must not drop any blocks");
2746 Block* block = _block_map[j];
2747 // Remove dead blocks from successor lists:
2748 for (int e = 0; e <= 1; e++) {
2749 GrowableArray<Block*>* l = e? block->exceptions(): block->successors();
2750 for (int k = 0; k < l->length(); k++) {
2751 Block* s = l->at(k);
2752 if (!s->has_post_order()) {
2753 if (CITraceTypeFlow) {
2754 tty->print("Removing dead %s successor of #%d: ", (e? "exceptional": "normal"), block->pre_order());
2755 s->print_value_on(tty);
2756 tty->cr();
2757 }
2758 l->remove(s);
2759 --k;
2760 }
2761 }
2762 }
2763 }
2764 }
2765
2766 // ------------------------------------------------------------------
2767 // ciTypeFlow::get_block_for
2768 //
2769 // Find a block with this ciBlock which has a compatible JsrSet.
2770 // If no such block exists, create it, unless the option is no_create.
2771 // If the option is create_backedge_copy, always create a fresh backedge copy.
2772 ciTypeFlow::Block* ciTypeFlow::get_block_for(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
2773 Arena* a = arena();
2774 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
2775 if (blocks == NULL) {
2776 // Query only?
2777 if (option == no_create) return NULL;
2778
2779 // Allocate the growable array.
2780 blocks = new (a) GrowableArray<Block*>(a, 4, 0, NULL);
2781 _idx_to_blocklist[ciBlockIndex] = blocks;
2782 }
2783
2784 if (option != create_backedge_copy) {
2785 int len = blocks->length();
2786 for (int i = 0; i < len; i++) {
2787 Block* block = blocks->at(i);
2788 if (!block->is_backedge_copy() && block->is_compatible_with(jsrs)) {
2789 return block;
2790 }
2791 }
2792 }
2793
2794 // Query only?
2795 if (option == no_create) return NULL;
2796
2797 // We did not find a compatible block. Create one.
2798 Block* new_block = new (a) Block(this, _methodBlocks->block(ciBlockIndex), jsrs);
2799 if (option == create_backedge_copy) new_block->set_backedge_copy(true);
2800 blocks->append(new_block);
2801 return new_block;
2802 }
2803
2804 // ------------------------------------------------------------------
2805 // ciTypeFlow::backedge_copy_count
2806 //
2807 int ciTypeFlow::backedge_copy_count(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs) const {
2808 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
2809
2810 if (blocks == NULL) {
2811 return 0;
2812 }
2813
2814 int count = 0;
2815 int len = blocks->length();
2816 for (int i = 0; i < len; i++) {
2817 Block* block = blocks->at(i);
2818 if (block->is_backedge_copy() && block->is_compatible_with(jsrs)) {
2819 count++;
2820 }
2821 }
2822
2823 return count;
2824 }
2825
2826 // ------------------------------------------------------------------
2827 // ciTypeFlow::do_flow
2828 //
2829 // Perform type inference flow analysis.
2830 void ciTypeFlow::do_flow() {
2831 if (CITraceTypeFlow) {
2832 tty->print_cr("\nPerforming flow analysis on method");
2833 method()->print();
2834 if (is_osr_flow()) tty->print(" at OSR bci %d", start_bci());
2835 tty->cr();
2836 method()->print_codes();
2837 }
2838 if (CITraceTypeFlow) {
2839 tty->print_cr("Initial CI Blocks");
2840 print_on(tty);
2841 }
2842 flow_types();
2843 // Watch for bailouts.
2844 if (failing()) {
2845 return;
2846 }
2847
2848 map_blocks();
2849
2850 if (CIPrintTypeFlow || CITraceTypeFlow) {
2851 rpo_print_on(tty);
2852 }
2853 }
2854
2855 // ------------------------------------------------------------------
2856 // ciTypeFlow::record_failure()
2857 // The ciTypeFlow object keeps track of failure reasons separately from the ciEnv.
2858 // This is required because there is not a 1-1 relation between the ciEnv and
2859 // the TypeFlow passes within a compilation task. For example, if the compiler
2860 // is considering inlining a method, it will request a TypeFlow. If that fails,
2861 // the compilation as a whole may continue without the inlining. Some TypeFlow
2862 // requests are not optional; if they fail the requestor is responsible for
2863 // copying the failure reason up to the ciEnv. (See Parse::Parse.)
2864 void ciTypeFlow::record_failure(const char* reason) {
2865 if (env()->log() != NULL) {
2866 env()->log()->elem("failure reason='%s' phase='typeflow'", reason);
2867 }
2868 if (_failure_reason == NULL) {
2869 // Record the first failure reason.
2870 _failure_reason = reason;
2871 }
2872 }
2873
2874 #ifndef PRODUCT
2875 // ------------------------------------------------------------------
2876 // ciTypeFlow::print_on
2877 void ciTypeFlow::print_on(outputStream* st) const {
2878 // Walk through CI blocks
2879 st->print_cr("********************************************************");
2880 st->print ("TypeFlow for ");
2881 method()->name()->print_symbol_on(st);
2882 int limit_bci = code_size();
2883 st->print_cr(" %d bytes", limit_bci);
2884 ciMethodBlocks *mblks = _methodBlocks;
2885 ciBlock* current = NULL;
2886 for (int bci = 0; bci < limit_bci; bci++) {
2887 ciBlock* blk = mblks->block_containing(bci);
2888 if (blk != NULL && blk != current) {
2889 current = blk;
2890 current->print_on(st);
2891
2892 GrowableArray<Block*>* blocks = _idx_to_blocklist[blk->index()];
2893 int num_blocks = (blocks == NULL) ? 0 : blocks->length();
2894
2895 if (num_blocks == 0) {
2896 st->print_cr(" No Blocks");
2897 } else {
2898 for (int i = 0; i < num_blocks; i++) {
2899 Block* block = blocks->at(i);
2900 block->print_on(st);
2901 }
2902 }
2903 st->print_cr("--------------------------------------------------------");
2904 st->cr();
2905 }
2906 }
2907 st->print_cr("********************************************************");
2908 st->cr();
2909 }
2910
2911 void ciTypeFlow::rpo_print_on(outputStream* st) const {
2912 st->print_cr("********************************************************");
2913 st->print ("TypeFlow for ");
2914 method()->name()->print_symbol_on(st);
2915 int limit_bci = code_size();
2916 st->print_cr(" %d bytes", limit_bci);
2917 for (Block* blk = _rpo_list; blk != NULL; blk = blk->rpo_next()) {
2918 blk->print_on(st);
2919 st->print_cr("--------------------------------------------------------");
2920 st->cr();
2921 }
2922 st->print_cr("********************************************************");
2923 st->cr();
2924 }
2925 #endif