1 /*
2 * Copyright 2000-2009 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
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 if (obj->is_klass()) {
716 // The type of ldc <class> is java.lang.Class
717 push_object(outer()->env()->Class_klass());
718 } else {
719 push_object(obj->klass());
720 }
721 } else {
722 push_translate(ciType::make(basic_type));
723 }
724 }
725
726 // ------------------------------------------------------------------
727 // ciTypeFlow::StateVector::do_multianewarray
728 void ciTypeFlow::StateVector::do_multianewarray(ciBytecodeStream* str) {
729 int dimensions = str->get_dimensions();
730 bool will_link;
731 ciArrayKlass* array_klass = str->get_klass(will_link)->as_array_klass();
732 if (!will_link) {
733 trap(str, array_klass, str->get_klass_index());
734 } else {
735 for (int i = 0; i < dimensions; i++) {
736 pop_int();
737 }
738 push_object(array_klass);
739 }
740 }
741
742 // ------------------------------------------------------------------
743 // ciTypeFlow::StateVector::do_new
744 void ciTypeFlow::StateVector::do_new(ciBytecodeStream* str) {
745 bool will_link;
746 ciKlass* klass = str->get_klass(will_link);
747 if (!will_link || str->is_unresolved_klass()) {
748 trap(str, klass, str->get_klass_index());
749 } else {
750 push_object(klass);
751 }
752 }
753
754 // ------------------------------------------------------------------
755 // ciTypeFlow::StateVector::do_newarray
756 void ciTypeFlow::StateVector::do_newarray(ciBytecodeStream* str) {
757 pop_int();
758 ciKlass* klass = ciTypeArrayKlass::make((BasicType)str->get_index());
759 push_object(klass);
760 }
761
762 // ------------------------------------------------------------------
763 // ciTypeFlow::StateVector::do_putfield
764 void ciTypeFlow::StateVector::do_putfield(ciBytecodeStream* str) {
765 do_putstatic(str);
766 if (_trap_bci != -1) return; // unloaded field holder, etc.
767 // could add assert here for type of object.
768 pop_object();
769 }
770
771 // ------------------------------------------------------------------
772 // ciTypeFlow::StateVector::do_putstatic
773 void ciTypeFlow::StateVector::do_putstatic(ciBytecodeStream* str) {
774 bool will_link;
775 ciField* field = str->get_field(will_link);
776 if (!will_link) {
777 trap(str, field->holder(), str->get_field_holder_index());
778 } else {
779 ciType* field_type = field->type();
780 ciType* type = pop_value();
781 // Do I want to check this type?
782 // assert(type->is_subtype_of(field_type), "bad type for field value");
783 if (field_type->is_two_word()) {
784 ciType* type2 = pop_value();
785 assert(type2->is_two_word(), "must be 2nd half");
786 assert(type == half_type(type2), "must be 2nd half");
787 }
788 }
789 }
790
791 // ------------------------------------------------------------------
792 // ciTypeFlow::StateVector::do_ret
793 void ciTypeFlow::StateVector::do_ret(ciBytecodeStream* str) {
794 Cell index = local(str->get_index());
795
796 ciType* address = type_at(index);
797 assert(address->is_return_address(), "bad return address");
798 set_type_at(index, bottom_type());
799 }
800
801 // ------------------------------------------------------------------
802 // ciTypeFlow::StateVector::trap
803 //
804 // Stop interpretation of this path with a trap.
805 void ciTypeFlow::StateVector::trap(ciBytecodeStream* str, ciKlass* klass, int index) {
806 _trap_bci = str->cur_bci();
807 _trap_index = index;
808
809 // Log information about this trap:
810 CompileLog* log = outer()->env()->log();
811 if (log != NULL) {
812 int mid = log->identify(outer()->method());
813 int kid = (klass == NULL)? -1: log->identify(klass);
814 log->begin_elem("uncommon_trap method='%d' bci='%d'", mid, str->cur_bci());
815 char buf[100];
816 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
817 index));
818 if (kid >= 0)
819 log->print(" klass='%d'", kid);
820 log->end_elem();
821 }
822 }
823
824 // ------------------------------------------------------------------
825 // ciTypeFlow::StateVector::do_null_assert
826 // Corresponds to graphKit::do_null_assert.
827 void ciTypeFlow::StateVector::do_null_assert(ciKlass* unloaded_klass) {
828 if (unloaded_klass->is_loaded()) {
829 // We failed to link, but we can still compute with this class,
830 // since it is loaded somewhere. The compiler will uncommon_trap
831 // if the object is not null, but the typeflow pass can not assume
832 // that the object will be null, otherwise it may incorrectly tell
833 // the parser that an object is known to be null. 4761344, 4807707
834 push_object(unloaded_klass);
835 } else {
836 // The class is not loaded anywhere. It is safe to model the
837 // null in the typestates, because we can compile in a null check
838 // which will deoptimize us if someone manages to load the
839 // class later.
840 push_null();
841 }
842 }
843
844
845 // ------------------------------------------------------------------
846 // ciTypeFlow::StateVector::apply_one_bytecode
847 //
848 // Apply the effect of one bytecode to this StateVector
849 bool ciTypeFlow::StateVector::apply_one_bytecode(ciBytecodeStream* str) {
850 _trap_bci = -1;
851 _trap_index = 0;
852
853 if (CITraceTypeFlow) {
854 tty->print_cr(">> Interpreting bytecode %d:%s", str->cur_bci(),
855 Bytecodes::name(str->cur_bc()));
856 }
857
858 switch(str->cur_bc()) {
859 case Bytecodes::_aaload: do_aaload(str); break;
860
861 case Bytecodes::_aastore:
862 {
863 pop_object();
864 pop_int();
865 pop_objArray();
866 break;
867 }
868 case Bytecodes::_aconst_null:
869 {
870 push_null();
871 break;
872 }
873 case Bytecodes::_aload: load_local_object(str->get_index()); break;
874 case Bytecodes::_aload_0: load_local_object(0); break;
875 case Bytecodes::_aload_1: load_local_object(1); break;
876 case Bytecodes::_aload_2: load_local_object(2); break;
877 case Bytecodes::_aload_3: load_local_object(3); break;
878
879 case Bytecodes::_anewarray:
880 {
881 pop_int();
882 bool will_link;
883 ciKlass* element_klass = str->get_klass(will_link);
884 if (!will_link) {
885 trap(str, element_klass, str->get_klass_index());
886 } else {
887 push_object(ciObjArrayKlass::make(element_klass));
888 }
889 break;
890 }
891 case Bytecodes::_areturn:
892 case Bytecodes::_ifnonnull:
893 case Bytecodes::_ifnull:
894 {
895 pop_object();
896 break;
897 }
898 case Bytecodes::_monitorenter:
899 {
900 pop_object();
901 set_monitor_count(monitor_count() + 1);
902 break;
903 }
904 case Bytecodes::_monitorexit:
905 {
906 pop_object();
907 assert(monitor_count() > 0, "must be a monitor to exit from");
908 set_monitor_count(monitor_count() - 1);
909 break;
910 }
911 case Bytecodes::_arraylength:
912 {
913 pop_array();
914 push_int();
915 break;
916 }
917 case Bytecodes::_astore: store_local_object(str->get_index()); break;
918 case Bytecodes::_astore_0: store_local_object(0); break;
919 case Bytecodes::_astore_1: store_local_object(1); break;
920 case Bytecodes::_astore_2: store_local_object(2); break;
921 case Bytecodes::_astore_3: store_local_object(3); break;
922
923 case Bytecodes::_athrow:
924 {
925 NEEDS_CLEANUP;
926 pop_object();
927 break;
928 }
929 case Bytecodes::_baload:
930 case Bytecodes::_caload:
931 case Bytecodes::_iaload:
932 case Bytecodes::_saload:
933 {
934 pop_int();
935 ciTypeArrayKlass* array_klass = pop_typeArray();
936 // Put assert here for right type?
937 push_int();
938 break;
939 }
940 case Bytecodes::_bastore:
941 case Bytecodes::_castore:
942 case Bytecodes::_iastore:
943 case Bytecodes::_sastore:
944 {
945 pop_int();
946 pop_int();
947 pop_typeArray();
948 // assert here?
949 break;
950 }
951 case Bytecodes::_bipush:
952 case Bytecodes::_iconst_m1:
953 case Bytecodes::_iconst_0:
954 case Bytecodes::_iconst_1:
955 case Bytecodes::_iconst_2:
956 case Bytecodes::_iconst_3:
957 case Bytecodes::_iconst_4:
958 case Bytecodes::_iconst_5:
959 case Bytecodes::_sipush:
960 {
961 push_int();
962 break;
963 }
964 case Bytecodes::_checkcast: do_checkcast(str); break;
965
966 case Bytecodes::_d2f:
967 {
968 pop_double();
969 push_float();
970 break;
971 }
972 case Bytecodes::_d2i:
973 {
974 pop_double();
975 push_int();
976 break;
977 }
978 case Bytecodes::_d2l:
979 {
980 pop_double();
981 push_long();
982 break;
983 }
984 case Bytecodes::_dadd:
985 case Bytecodes::_ddiv:
986 case Bytecodes::_dmul:
987 case Bytecodes::_drem:
988 case Bytecodes::_dsub:
989 {
990 pop_double();
991 pop_double();
992 push_double();
993 break;
994 }
995 case Bytecodes::_daload:
996 {
997 pop_int();
998 ciTypeArrayKlass* array_klass = pop_typeArray();
999 // Put assert here for right type?
1000 push_double();
1001 break;
1002 }
1003 case Bytecodes::_dastore:
1004 {
1005 pop_double();
1006 pop_int();
1007 pop_typeArray();
1008 // assert here?
1009 break;
1010 }
1011 case Bytecodes::_dcmpg:
1012 case Bytecodes::_dcmpl:
1013 {
1014 pop_double();
1015 pop_double();
1016 push_int();
1017 break;
1018 }
1019 case Bytecodes::_dconst_0:
1020 case Bytecodes::_dconst_1:
1021 {
1022 push_double();
1023 break;
1024 }
1025 case Bytecodes::_dload: load_local_double(str->get_index()); break;
1026 case Bytecodes::_dload_0: load_local_double(0); break;
1027 case Bytecodes::_dload_1: load_local_double(1); break;
1028 case Bytecodes::_dload_2: load_local_double(2); break;
1029 case Bytecodes::_dload_3: load_local_double(3); break;
1030
1031 case Bytecodes::_dneg:
1032 {
1033 pop_double();
1034 push_double();
1035 break;
1036 }
1037 case Bytecodes::_dreturn:
1038 {
1039 pop_double();
1040 break;
1041 }
1042 case Bytecodes::_dstore: store_local_double(str->get_index()); break;
1043 case Bytecodes::_dstore_0: store_local_double(0); break;
1044 case Bytecodes::_dstore_1: store_local_double(1); break;
1045 case Bytecodes::_dstore_2: store_local_double(2); break;
1046 case Bytecodes::_dstore_3: store_local_double(3); break;
1047
1048 case Bytecodes::_dup:
1049 {
1050 push(type_at_tos());
1051 break;
1052 }
1053 case Bytecodes::_dup_x1:
1054 {
1055 ciType* value1 = pop_value();
1056 ciType* value2 = pop_value();
1057 push(value1);
1058 push(value2);
1059 push(value1);
1060 break;
1061 }
1062 case Bytecodes::_dup_x2:
1063 {
1064 ciType* value1 = pop_value();
1065 ciType* value2 = pop_value();
1066 ciType* value3 = pop_value();
1067 push(value1);
1068 push(value3);
1069 push(value2);
1070 push(value1);
1071 break;
1072 }
1073 case Bytecodes::_dup2:
1074 {
1075 ciType* value1 = pop_value();
1076 ciType* value2 = pop_value();
1077 push(value2);
1078 push(value1);
1079 push(value2);
1080 push(value1);
1081 break;
1082 }
1083 case Bytecodes::_dup2_x1:
1084 {
1085 ciType* value1 = pop_value();
1086 ciType* value2 = pop_value();
1087 ciType* value3 = pop_value();
1088 push(value2);
1089 push(value1);
1090 push(value3);
1091 push(value2);
1092 push(value1);
1093 break;
1094 }
1095 case Bytecodes::_dup2_x2:
1096 {
1097 ciType* value1 = pop_value();
1098 ciType* value2 = pop_value();
1099 ciType* value3 = pop_value();
1100 ciType* value4 = pop_value();
1101 push(value2);
1102 push(value1);
1103 push(value4);
1104 push(value3);
1105 push(value2);
1106 push(value1);
1107 break;
1108 }
1109 case Bytecodes::_f2d:
1110 {
1111 pop_float();
1112 push_double();
1113 break;
1114 }
1115 case Bytecodes::_f2i:
1116 {
1117 pop_float();
1118 push_int();
1119 break;
1120 }
1121 case Bytecodes::_f2l:
1122 {
1123 pop_float();
1124 push_long();
1125 break;
1126 }
1127 case Bytecodes::_fadd:
1128 case Bytecodes::_fdiv:
1129 case Bytecodes::_fmul:
1130 case Bytecodes::_frem:
1131 case Bytecodes::_fsub:
1132 {
1133 pop_float();
1134 pop_float();
1135 push_float();
1136 break;
1137 }
1138 case Bytecodes::_faload:
1139 {
1140 pop_int();
1141 ciTypeArrayKlass* array_klass = pop_typeArray();
1142 // Put assert here.
1143 push_float();
1144 break;
1145 }
1146 case Bytecodes::_fastore:
1147 {
1148 pop_float();
1149 pop_int();
1150 ciTypeArrayKlass* array_klass = pop_typeArray();
1151 // Put assert here.
1152 break;
1153 }
1154 case Bytecodes::_fcmpg:
1155 case Bytecodes::_fcmpl:
1156 {
1157 pop_float();
1158 pop_float();
1159 push_int();
1160 break;
1161 }
1162 case Bytecodes::_fconst_0:
1163 case Bytecodes::_fconst_1:
1164 case Bytecodes::_fconst_2:
1165 {
1166 push_float();
1167 break;
1168 }
1169 case Bytecodes::_fload: load_local_float(str->get_index()); break;
1170 case Bytecodes::_fload_0: load_local_float(0); break;
1171 case Bytecodes::_fload_1: load_local_float(1); break;
1172 case Bytecodes::_fload_2: load_local_float(2); break;
1173 case Bytecodes::_fload_3: load_local_float(3); break;
1174
1175 case Bytecodes::_fneg:
1176 {
1177 pop_float();
1178 push_float();
1179 break;
1180 }
1181 case Bytecodes::_freturn:
1182 {
1183 pop_float();
1184 break;
1185 }
1186 case Bytecodes::_fstore: store_local_float(str->get_index()); break;
1187 case Bytecodes::_fstore_0: store_local_float(0); break;
1188 case Bytecodes::_fstore_1: store_local_float(1); break;
1189 case Bytecodes::_fstore_2: store_local_float(2); break;
1190 case Bytecodes::_fstore_3: store_local_float(3); break;
1191
1192 case Bytecodes::_getfield: do_getfield(str); break;
1193 case Bytecodes::_getstatic: do_getstatic(str); break;
1194
1195 case Bytecodes::_goto:
1196 case Bytecodes::_goto_w:
1197 case Bytecodes::_nop:
1198 case Bytecodes::_return:
1199 {
1200 // do nothing.
1201 break;
1202 }
1203 case Bytecodes::_i2b:
1204 case Bytecodes::_i2c:
1205 case Bytecodes::_i2s:
1206 case Bytecodes::_ineg:
1207 {
1208 pop_int();
1209 push_int();
1210 break;
1211 }
1212 case Bytecodes::_i2d:
1213 {
1214 pop_int();
1215 push_double();
1216 break;
1217 }
1218 case Bytecodes::_i2f:
1219 {
1220 pop_int();
1221 push_float();
1222 break;
1223 }
1224 case Bytecodes::_i2l:
1225 {
1226 pop_int();
1227 push_long();
1228 break;
1229 }
1230 case Bytecodes::_iadd:
1231 case Bytecodes::_iand:
1232 case Bytecodes::_idiv:
1233 case Bytecodes::_imul:
1234 case Bytecodes::_ior:
1235 case Bytecodes::_irem:
1236 case Bytecodes::_ishl:
1237 case Bytecodes::_ishr:
1238 case Bytecodes::_isub:
1239 case Bytecodes::_iushr:
1240 case Bytecodes::_ixor:
1241 {
1242 pop_int();
1243 pop_int();
1244 push_int();
1245 break;
1246 }
1247 case Bytecodes::_if_acmpeq:
1248 case Bytecodes::_if_acmpne:
1249 {
1250 pop_object();
1251 pop_object();
1252 break;
1253 }
1254 case Bytecodes::_if_icmpeq:
1255 case Bytecodes::_if_icmpge:
1256 case Bytecodes::_if_icmpgt:
1257 case Bytecodes::_if_icmple:
1258 case Bytecodes::_if_icmplt:
1259 case Bytecodes::_if_icmpne:
1260 {
1261 pop_int();
1262 pop_int();
1263 break;
1264 }
1265 case Bytecodes::_ifeq:
1266 case Bytecodes::_ifle:
1267 case Bytecodes::_iflt:
1268 case Bytecodes::_ifge:
1269 case Bytecodes::_ifgt:
1270 case Bytecodes::_ifne:
1271 case Bytecodes::_ireturn:
1272 case Bytecodes::_lookupswitch:
1273 case Bytecodes::_tableswitch:
1274 {
1275 pop_int();
1276 break;
1277 }
1278 case Bytecodes::_iinc:
1279 {
1280 int lnum = str->get_index();
1281 check_int(local(lnum));
1282 store_to_local(lnum);
1283 break;
1284 }
1285 case Bytecodes::_iload: load_local_int(str->get_index()); break;
1286 case Bytecodes::_iload_0: load_local_int(0); break;
1287 case Bytecodes::_iload_1: load_local_int(1); break;
1288 case Bytecodes::_iload_2: load_local_int(2); break;
1289 case Bytecodes::_iload_3: load_local_int(3); break;
1290
1291 case Bytecodes::_instanceof:
1292 {
1293 // Check for uncommon trap:
1294 do_checkcast(str);
1295 pop_object();
1296 push_int();
1297 break;
1298 }
1299 case Bytecodes::_invokeinterface: do_invoke(str, true); break;
1300 case Bytecodes::_invokespecial: do_invoke(str, true); break;
1301 case Bytecodes::_invokestatic: do_invoke(str, false); break;
1302 case Bytecodes::_invokevirtual: do_invoke(str, true); break;
1303 case Bytecodes::_invokedynamic: do_invoke(str, false); break;
1304
1305 case Bytecodes::_istore: store_local_int(str->get_index()); break;
1306 case Bytecodes::_istore_0: store_local_int(0); break;
1307 case Bytecodes::_istore_1: store_local_int(1); break;
1308 case Bytecodes::_istore_2: store_local_int(2); break;
1309 case Bytecodes::_istore_3: store_local_int(3); break;
1310
1311 case Bytecodes::_jsr:
1312 case Bytecodes::_jsr_w: do_jsr(str); break;
1313
1314 case Bytecodes::_l2d:
1315 {
1316 pop_long();
1317 push_double();
1318 break;
1319 }
1320 case Bytecodes::_l2f:
1321 {
1322 pop_long();
1323 push_float();
1324 break;
1325 }
1326 case Bytecodes::_l2i:
1327 {
1328 pop_long();
1329 push_int();
1330 break;
1331 }
1332 case Bytecodes::_ladd:
1333 case Bytecodes::_land:
1334 case Bytecodes::_ldiv:
1335 case Bytecodes::_lmul:
1336 case Bytecodes::_lor:
1337 case Bytecodes::_lrem:
1338 case Bytecodes::_lsub:
1339 case Bytecodes::_lxor:
1340 {
1341 pop_long();
1342 pop_long();
1343 push_long();
1344 break;
1345 }
1346 case Bytecodes::_laload:
1347 {
1348 pop_int();
1349 ciTypeArrayKlass* array_klass = pop_typeArray();
1350 // Put assert here for right type?
1351 push_long();
1352 break;
1353 }
1354 case Bytecodes::_lastore:
1355 {
1356 pop_long();
1357 pop_int();
1358 pop_typeArray();
1359 // assert here?
1360 break;
1361 }
1362 case Bytecodes::_lcmp:
1363 {
1364 pop_long();
1365 pop_long();
1366 push_int();
1367 break;
1368 }
1369 case Bytecodes::_lconst_0:
1370 case Bytecodes::_lconst_1:
1371 {
1372 push_long();
1373 break;
1374 }
1375 case Bytecodes::_ldc:
1376 case Bytecodes::_ldc_w:
1377 case Bytecodes::_ldc2_w:
1378 {
1379 do_ldc(str);
1380 break;
1381 }
1382
1383 case Bytecodes::_lload: load_local_long(str->get_index()); break;
1384 case Bytecodes::_lload_0: load_local_long(0); break;
1385 case Bytecodes::_lload_1: load_local_long(1); break;
1386 case Bytecodes::_lload_2: load_local_long(2); break;
1387 case Bytecodes::_lload_3: load_local_long(3); break;
1388
1389 case Bytecodes::_lneg:
1390 {
1391 pop_long();
1392 push_long();
1393 break;
1394 }
1395 case Bytecodes::_lreturn:
1396 {
1397 pop_long();
1398 break;
1399 }
1400 case Bytecodes::_lshl:
1401 case Bytecodes::_lshr:
1402 case Bytecodes::_lushr:
1403 {
1404 pop_int();
1405 pop_long();
1406 push_long();
1407 break;
1408 }
1409 case Bytecodes::_lstore: store_local_long(str->get_index()); break;
1410 case Bytecodes::_lstore_0: store_local_long(0); break;
1411 case Bytecodes::_lstore_1: store_local_long(1); break;
1412 case Bytecodes::_lstore_2: store_local_long(2); break;
1413 case Bytecodes::_lstore_3: store_local_long(3); break;
1414
1415 case Bytecodes::_multianewarray: do_multianewarray(str); break;
1416
1417 case Bytecodes::_new: do_new(str); break;
1418
1419 case Bytecodes::_newarray: do_newarray(str); break;
1420
1421 case Bytecodes::_pop:
1422 {
1423 pop();
1424 break;
1425 }
1426 case Bytecodes::_pop2:
1427 {
1428 pop();
1429 pop();
1430 break;
1431 }
1432
1433 case Bytecodes::_putfield: do_putfield(str); break;
1434 case Bytecodes::_putstatic: do_putstatic(str); break;
1435
1436 case Bytecodes::_ret: do_ret(str); break;
1437
1438 case Bytecodes::_swap:
1439 {
1440 ciType* value1 = pop_value();
1441 ciType* value2 = pop_value();
1442 push(value1);
1443 push(value2);
1444 break;
1445 }
1446 case Bytecodes::_wide:
1447 default:
1448 {
1449 // The iterator should skip this.
1450 ShouldNotReachHere();
1451 break;
1452 }
1453 }
1454
1455 if (CITraceTypeFlow) {
1456 print_on(tty);
1457 }
1458
1459 return (_trap_bci != -1);
1460 }
1461
1462 #ifndef PRODUCT
1463 // ------------------------------------------------------------------
1464 // ciTypeFlow::StateVector::print_cell_on
1465 void ciTypeFlow::StateVector::print_cell_on(outputStream* st, Cell c) const {
1466 ciType* type = type_at(c);
1467 if (type == top_type()) {
1468 st->print("top");
1469 } else if (type == bottom_type()) {
1470 st->print("bottom");
1471 } else if (type == null_type()) {
1472 st->print("null");
1473 } else if (type == long2_type()) {
1474 st->print("long2");
1475 } else if (type == double2_type()) {
1476 st->print("double2");
1477 } else if (is_int(type)) {
1478 st->print("int");
1479 } else if (is_long(type)) {
1480 st->print("long");
1481 } else if (is_float(type)) {
1482 st->print("float");
1483 } else if (is_double(type)) {
1484 st->print("double");
1485 } else if (type->is_return_address()) {
1486 st->print("address(%d)", type->as_return_address()->bci());
1487 } else {
1488 if (type->is_klass()) {
1489 type->as_klass()->name()->print_symbol_on(st);
1490 } else {
1491 st->print("UNEXPECTED TYPE");
1492 type->print();
1493 }
1494 }
1495 }
1496
1497 // ------------------------------------------------------------------
1498 // ciTypeFlow::StateVector::print_on
1499 void ciTypeFlow::StateVector::print_on(outputStream* st) const {
1500 int num_locals = _outer->max_locals();
1501 int num_stack = stack_size();
1502 int num_monitors = monitor_count();
1503 st->print_cr(" State : locals %d, stack %d, monitors %d", num_locals, num_stack, num_monitors);
1504 if (num_stack >= 0) {
1505 int i;
1506 for (i = 0; i < num_locals; i++) {
1507 st->print(" local %2d : ", i);
1508 print_cell_on(st, local(i));
1509 st->cr();
1510 }
1511 for (i = 0; i < num_stack; i++) {
1512 st->print(" stack %2d : ", i);
1513 print_cell_on(st, stack(i));
1514 st->cr();
1515 }
1516 }
1517 }
1518 #endif
1519
1520
1521 // ------------------------------------------------------------------
1522 // ciTypeFlow::SuccIter::next
1523 //
1524 void ciTypeFlow::SuccIter::next() {
1525 int succ_ct = _pred->successors()->length();
1526 int next = _index + 1;
1527 if (next < succ_ct) {
1528 _index = next;
1529 _succ = _pred->successors()->at(next);
1530 return;
1531 }
1532 for (int i = next - succ_ct; i < _pred->exceptions()->length(); i++) {
1533 // Do not compile any code for unloaded exception types.
1534 // Following compiler passes are responsible for doing this also.
1535 ciInstanceKlass* exception_klass = _pred->exc_klasses()->at(i);
1536 if (exception_klass->is_loaded()) {
1537 _index = next;
1538 _succ = _pred->exceptions()->at(i);
1539 return;
1540 }
1541 next++;
1542 }
1543 _index = -1;
1544 _succ = NULL;
1545 }
1546
1547 // ------------------------------------------------------------------
1548 // ciTypeFlow::SuccIter::set_succ
1549 //
1550 void ciTypeFlow::SuccIter::set_succ(Block* succ) {
1551 int succ_ct = _pred->successors()->length();
1552 if (_index < succ_ct) {
1553 _pred->successors()->at_put(_index, succ);
1554 } else {
1555 int idx = _index - succ_ct;
1556 _pred->exceptions()->at_put(idx, succ);
1557 }
1558 }
1559
1560 // ciTypeFlow::Block
1561 //
1562 // A basic block.
1563
1564 // ------------------------------------------------------------------
1565 // ciTypeFlow::Block::Block
1566 ciTypeFlow::Block::Block(ciTypeFlow* outer,
1567 ciBlock *ciblk,
1568 ciTypeFlow::JsrSet* jsrs) {
1569 _ciblock = ciblk;
1570 _exceptions = NULL;
1571 _exc_klasses = NULL;
1572 _successors = NULL;
1573 _state = new (outer->arena()) StateVector(outer);
1574 JsrSet* new_jsrs =
1575 new (outer->arena()) JsrSet(outer->arena(), jsrs->size());
1576 jsrs->copy_into(new_jsrs);
1577 _jsrs = new_jsrs;
1578 _next = NULL;
1579 _on_work_list = false;
1580 _backedge_copy = false;
1581 _exception_entry = false;
1582 _trap_bci = -1;
1583 _trap_index = 0;
1584 df_init();
1585
1586 if (CITraceTypeFlow) {
1587 tty->print_cr(">> Created new block");
1588 print_on(tty);
1589 }
1590
1591 assert(this->outer() == outer, "outer link set up");
1592 assert(!outer->have_block_count(), "must not have mapped blocks yet");
1593 }
1594
1595 // ------------------------------------------------------------------
1596 // ciTypeFlow::Block::df_init
1597 void ciTypeFlow::Block::df_init() {
1598 _pre_order = -1; assert(!has_pre_order(), "");
1599 _post_order = -1; assert(!has_post_order(), "");
1600 _loop = NULL;
1601 _irreducible_entry = false;
1602 _rpo_next = NULL;
1603 }
1604
1605 // ------------------------------------------------------------------
1606 // ciTypeFlow::Block::successors
1607 //
1608 // Get the successors for this Block.
1609 GrowableArray<ciTypeFlow::Block*>*
1610 ciTypeFlow::Block::successors(ciBytecodeStream* str,
1611 ciTypeFlow::StateVector* state,
1612 ciTypeFlow::JsrSet* jsrs) {
1613 if (_successors == NULL) {
1614 if (CITraceTypeFlow) {
1615 tty->print(">> Computing successors for block ");
1616 print_value_on(tty);
1617 tty->cr();
1618 }
1619
1620 ciTypeFlow* analyzer = outer();
1621 Arena* arena = analyzer->arena();
1622 Block* block = NULL;
1623 bool has_successor = !has_trap() &&
1624 (control() != ciBlock::fall_through_bci || limit() < analyzer->code_size());
1625 if (!has_successor) {
1626 _successors =
1627 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1628 // No successors
1629 } else if (control() == ciBlock::fall_through_bci) {
1630 assert(str->cur_bci() == limit(), "bad block end");
1631 // This block simply falls through to the next.
1632 _successors =
1633 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1634
1635 Block* block = analyzer->block_at(limit(), _jsrs);
1636 assert(_successors->length() == FALL_THROUGH, "");
1637 _successors->append(block);
1638 } else {
1639 int current_bci = str->cur_bci();
1640 int next_bci = str->next_bci();
1641 int branch_bci = -1;
1642 Block* target = NULL;
1643 assert(str->next_bci() == limit(), "bad block end");
1644 // This block is not a simple fall-though. Interpret
1645 // the current bytecode to find our successors.
1646 switch (str->cur_bc()) {
1647 case Bytecodes::_ifeq: case Bytecodes::_ifne:
1648 case Bytecodes::_iflt: case Bytecodes::_ifge:
1649 case Bytecodes::_ifgt: case Bytecodes::_ifle:
1650 case Bytecodes::_if_icmpeq: case Bytecodes::_if_icmpne:
1651 case Bytecodes::_if_icmplt: case Bytecodes::_if_icmpge:
1652 case Bytecodes::_if_icmpgt: case Bytecodes::_if_icmple:
1653 case Bytecodes::_if_acmpeq: case Bytecodes::_if_acmpne:
1654 case Bytecodes::_ifnull: case Bytecodes::_ifnonnull:
1655 // Our successors are the branch target and the next bci.
1656 branch_bci = str->get_dest();
1657 _successors =
1658 new (arena) GrowableArray<Block*>(arena, 2, 0, NULL);
1659 assert(_successors->length() == IF_NOT_TAKEN, "");
1660 _successors->append(analyzer->block_at(next_bci, jsrs));
1661 assert(_successors->length() == IF_TAKEN, "");
1662 _successors->append(analyzer->block_at(branch_bci, jsrs));
1663 break;
1664
1665 case Bytecodes::_goto:
1666 branch_bci = str->get_dest();
1667 _successors =
1668 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1669 assert(_successors->length() == GOTO_TARGET, "");
1670 _successors->append(analyzer->block_at(branch_bci, jsrs));
1671 break;
1672
1673 case Bytecodes::_jsr:
1674 branch_bci = str->get_dest();
1675 _successors =
1676 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1677 assert(_successors->length() == GOTO_TARGET, "");
1678 _successors->append(analyzer->block_at(branch_bci, jsrs));
1679 break;
1680
1681 case Bytecodes::_goto_w:
1682 case Bytecodes::_jsr_w:
1683 _successors =
1684 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1685 assert(_successors->length() == GOTO_TARGET, "");
1686 _successors->append(analyzer->block_at(str->get_far_dest(), jsrs));
1687 break;
1688
1689 case Bytecodes::_tableswitch: {
1690 Bytecode_tableswitch *tableswitch =
1691 Bytecode_tableswitch_at(str->cur_bcp());
1692
1693 int len = tableswitch->length();
1694 _successors =
1695 new (arena) GrowableArray<Block*>(arena, len+1, 0, NULL);
1696 int bci = current_bci + tableswitch->default_offset();
1697 Block* block = analyzer->block_at(bci, jsrs);
1698 assert(_successors->length() == SWITCH_DEFAULT, "");
1699 _successors->append(block);
1700 while (--len >= 0) {
1701 int bci = current_bci + tableswitch->dest_offset_at(len);
1702 block = analyzer->block_at(bci, jsrs);
1703 assert(_successors->length() >= SWITCH_CASES, "");
1704 _successors->append_if_missing(block);
1705 }
1706 break;
1707 }
1708
1709 case Bytecodes::_lookupswitch: {
1710 Bytecode_lookupswitch *lookupswitch =
1711 Bytecode_lookupswitch_at(str->cur_bcp());
1712
1713 int npairs = lookupswitch->number_of_pairs();
1714 _successors =
1715 new (arena) GrowableArray<Block*>(arena, npairs+1, 0, NULL);
1716 int bci = current_bci + lookupswitch->default_offset();
1717 Block* block = analyzer->block_at(bci, jsrs);
1718 assert(_successors->length() == SWITCH_DEFAULT, "");
1719 _successors->append(block);
1720 while(--npairs >= 0) {
1721 LookupswitchPair *pair = lookupswitch->pair_at(npairs);
1722 int bci = current_bci + pair->offset();
1723 Block* block = analyzer->block_at(bci, jsrs);
1724 assert(_successors->length() >= SWITCH_CASES, "");
1725 _successors->append_if_missing(block);
1726 }
1727 break;
1728 }
1729
1730 case Bytecodes::_athrow: case Bytecodes::_ireturn:
1731 case Bytecodes::_lreturn: case Bytecodes::_freturn:
1732 case Bytecodes::_dreturn: case Bytecodes::_areturn:
1733 case Bytecodes::_return:
1734 _successors =
1735 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1736 // No successors
1737 break;
1738
1739 case Bytecodes::_ret: {
1740 _successors =
1741 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1742
1743 Cell local = state->local(str->get_index());
1744 ciType* return_address = state->type_at(local);
1745 assert(return_address->is_return_address(), "verify: wrong type");
1746 int bci = return_address->as_return_address()->bci();
1747 assert(_successors->length() == GOTO_TARGET, "");
1748 _successors->append(analyzer->block_at(bci, jsrs));
1749 break;
1750 }
1751
1752 case Bytecodes::_wide:
1753 default:
1754 ShouldNotReachHere();
1755 break;
1756 }
1757 }
1758 }
1759 return _successors;
1760 }
1761
1762 // ------------------------------------------------------------------
1763 // ciTypeFlow::Block:compute_exceptions
1764 //
1765 // Compute the exceptional successors and types for this Block.
1766 void ciTypeFlow::Block::compute_exceptions() {
1767 assert(_exceptions == NULL && _exc_klasses == NULL, "repeat");
1768
1769 if (CITraceTypeFlow) {
1770 tty->print(">> Computing exceptions for block ");
1771 print_value_on(tty);
1772 tty->cr();
1773 }
1774
1775 ciTypeFlow* analyzer = outer();
1776 Arena* arena = analyzer->arena();
1777
1778 // Any bci in the block will do.
1779 ciExceptionHandlerStream str(analyzer->method(), start());
1780
1781 // Allocate our growable arrays.
1782 int exc_count = str.count();
1783 _exceptions = new (arena) GrowableArray<Block*>(arena, exc_count, 0, NULL);
1784 _exc_klasses = new (arena) GrowableArray<ciInstanceKlass*>(arena, exc_count,
1785 0, NULL);
1786
1787 for ( ; !str.is_done(); str.next()) {
1788 ciExceptionHandler* handler = str.handler();
1789 int bci = handler->handler_bci();
1790 ciInstanceKlass* klass = NULL;
1791 if (bci == -1) {
1792 // There is no catch all. It is possible to exit the method.
1793 break;
1794 }
1795 if (handler->is_catch_all()) {
1796 klass = analyzer->env()->Throwable_klass();
1797 } else {
1798 klass = handler->catch_klass();
1799 }
1800 _exceptions->append(analyzer->block_at(bci, _jsrs));
1801 _exc_klasses->append(klass);
1802 }
1803 }
1804
1805 // ------------------------------------------------------------------
1806 // ciTypeFlow::Block::set_backedge_copy
1807 // Use this only to make a pre-existing public block into a backedge copy.
1808 void ciTypeFlow::Block::set_backedge_copy(bool z) {
1809 assert(z || (z == is_backedge_copy()), "cannot make a backedge copy public");
1810 _backedge_copy = z;
1811 }
1812
1813 // ------------------------------------------------------------------
1814 // ciTypeFlow::Block::is_clonable_exit
1815 //
1816 // At most 2 normal successors, one of which continues looping,
1817 // and all exceptional successors must exit.
1818 bool ciTypeFlow::Block::is_clonable_exit(ciTypeFlow::Loop* lp) {
1819 int normal_cnt = 0;
1820 int in_loop_cnt = 0;
1821 for (SuccIter iter(this); !iter.done(); iter.next()) {
1822 Block* succ = iter.succ();
1823 if (iter.is_normal_ctrl()) {
1824 if (++normal_cnt > 2) return false;
1825 if (lp->contains(succ->loop())) {
1826 if (++in_loop_cnt > 1) return false;
1827 }
1828 } else {
1829 if (lp->contains(succ->loop())) return false;
1830 }
1831 }
1832 return in_loop_cnt == 1;
1833 }
1834
1835 // ------------------------------------------------------------------
1836 // ciTypeFlow::Block::looping_succ
1837 //
1838 ciTypeFlow::Block* ciTypeFlow::Block::looping_succ(ciTypeFlow::Loop* lp) {
1839 assert(successors()->length() <= 2, "at most 2 normal successors");
1840 for (SuccIter iter(this); !iter.done(); iter.next()) {
1841 Block* succ = iter.succ();
1842 if (lp->contains(succ->loop())) {
1843 return succ;
1844 }
1845 }
1846 return NULL;
1847 }
1848
1849 #ifndef PRODUCT
1850 // ------------------------------------------------------------------
1851 // ciTypeFlow::Block::print_value_on
1852 void ciTypeFlow::Block::print_value_on(outputStream* st) const {
1853 if (has_pre_order()) st->print("#%-2d ", pre_order());
1854 if (has_rpo()) st->print("rpo#%-2d ", rpo());
1855 st->print("[%d - %d)", start(), limit());
1856 if (is_loop_head()) st->print(" lphd");
1857 if (is_irreducible_entry()) st->print(" irred");
1858 if (_jsrs->size() > 0) { st->print("/"); _jsrs->print_on(st); }
1859 if (is_backedge_copy()) st->print("/backedge_copy");
1860 }
1861
1862 // ------------------------------------------------------------------
1863 // ciTypeFlow::Block::print_on
1864 void ciTypeFlow::Block::print_on(outputStream* st) const {
1865 if ((Verbose || WizardMode)) {
1866 outer()->method()->print_codes_on(start(), limit(), st);
1867 }
1868 st->print_cr(" ==================================================== ");
1869 st->print (" ");
1870 print_value_on(st);
1871 st->print(" Stored locals: "); def_locals()->print_on(st, outer()->method()->max_locals()); tty->cr();
1872 if (loop() && loop()->parent() != NULL) {
1873 st->print(" loops:");
1874 Loop* lp = loop();
1875 do {
1876 st->print(" %d<-%d", lp->head()->pre_order(),lp->tail()->pre_order());
1877 if (lp->is_irreducible()) st->print("(ir)");
1878 lp = lp->parent();
1879 } while (lp->parent() != NULL);
1880 }
1881 st->cr();
1882 _state->print_on(st);
1883 if (_successors == NULL) {
1884 st->print_cr(" No successor information");
1885 } else {
1886 int num_successors = _successors->length();
1887 st->print_cr(" Successors : %d", num_successors);
1888 for (int i = 0; i < num_successors; i++) {
1889 Block* successor = _successors->at(i);
1890 st->print(" ");
1891 successor->print_value_on(st);
1892 st->cr();
1893 }
1894 }
1895 if (_exceptions == NULL) {
1896 st->print_cr(" No exception information");
1897 } else {
1898 int num_exceptions = _exceptions->length();
1899 st->print_cr(" Exceptions : %d", num_exceptions);
1900 for (int i = 0; i < num_exceptions; i++) {
1901 Block* exc_succ = _exceptions->at(i);
1902 ciInstanceKlass* exc_klass = _exc_klasses->at(i);
1903 st->print(" ");
1904 exc_succ->print_value_on(st);
1905 st->print(" -- ");
1906 exc_klass->name()->print_symbol_on(st);
1907 st->cr();
1908 }
1909 }
1910 if (has_trap()) {
1911 st->print_cr(" Traps on %d with trap index %d", trap_bci(), trap_index());
1912 }
1913 st->print_cr(" ==================================================== ");
1914 }
1915 #endif
1916
1917 #ifndef PRODUCT
1918 // ------------------------------------------------------------------
1919 // ciTypeFlow::LocalSet::print_on
1920 void ciTypeFlow::LocalSet::print_on(outputStream* st, int limit) const {
1921 st->print("{");
1922 for (int i = 0; i < max; i++) {
1923 if (test(i)) st->print(" %d", i);
1924 }
1925 if (limit > max) {
1926 st->print(" %d..%d ", max, limit);
1927 }
1928 st->print(" }");
1929 }
1930 #endif
1931
1932 // ciTypeFlow
1933 //
1934 // This is a pass over the bytecodes which computes the following:
1935 // basic block structure
1936 // interpreter type-states (a la the verifier)
1937
1938 // ------------------------------------------------------------------
1939 // ciTypeFlow::ciTypeFlow
1940 ciTypeFlow::ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci) {
1941 _env = env;
1942 _method = method;
1943 _methodBlocks = method->get_method_blocks();
1944 _max_locals = method->max_locals();
1945 _max_stack = method->max_stack();
1946 _code_size = method->code_size();
1947 _has_irreducible_entry = false;
1948 _osr_bci = osr_bci;
1949 _failure_reason = NULL;
1950 assert(start_bci() >= 0 && start_bci() < code_size() , "correct osr_bci argument");
1951 _work_list = NULL;
1952
1953 _ciblock_count = _methodBlocks->num_blocks();
1954 _idx_to_blocklist = NEW_ARENA_ARRAY(arena(), GrowableArray<Block*>*, _ciblock_count);
1955 for (int i = 0; i < _ciblock_count; i++) {
1956 _idx_to_blocklist[i] = NULL;
1957 }
1958 _block_map = NULL; // until all blocks are seen
1959 _jsr_count = 0;
1960 _jsr_records = NULL;
1961 }
1962
1963 // ------------------------------------------------------------------
1964 // ciTypeFlow::work_list_next
1965 //
1966 // Get the next basic block from our work list.
1967 ciTypeFlow::Block* ciTypeFlow::work_list_next() {
1968 assert(!work_list_empty(), "work list must not be empty");
1969 Block* next_block = _work_list;
1970 _work_list = next_block->next();
1971 next_block->set_next(NULL);
1972 next_block->set_on_work_list(false);
1973 return next_block;
1974 }
1975
1976 // ------------------------------------------------------------------
1977 // ciTypeFlow::add_to_work_list
1978 //
1979 // Add a basic block to our work list.
1980 // List is sorted by decreasing postorder sort (same as increasing RPO)
1981 void ciTypeFlow::add_to_work_list(ciTypeFlow::Block* block) {
1982 assert(!block->is_on_work_list(), "must not already be on work list");
1983
1984 if (CITraceTypeFlow) {
1985 tty->print(">> Adding block ");
1986 block->print_value_on(tty);
1987 tty->print_cr(" to the work list : ");
1988 }
1989
1990 block->set_on_work_list(true);
1991
1992 // decreasing post order sort
1993
1994 Block* prev = NULL;
1995 Block* current = _work_list;
1996 int po = block->post_order();
1997 while (current != NULL) {
1998 if (!current->has_post_order() || po > current->post_order())
1999 break;
2000 prev = current;
2001 current = current->next();
2002 }
2003 if (prev == NULL) {
2004 block->set_next(_work_list);
2005 _work_list = block;
2006 } else {
2007 block->set_next(current);
2008 prev->set_next(block);
2009 }
2010
2011 if (CITraceTypeFlow) {
2012 tty->cr();
2013 }
2014 }
2015
2016 // ------------------------------------------------------------------
2017 // ciTypeFlow::block_at
2018 //
2019 // Return the block beginning at bci which has a JsrSet compatible
2020 // with jsrs.
2021 ciTypeFlow::Block* ciTypeFlow::block_at(int bci, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
2022 // First find the right ciBlock.
2023 if (CITraceTypeFlow) {
2024 tty->print(">> Requesting block for %d/", bci);
2025 jsrs->print_on(tty);
2026 tty->cr();
2027 }
2028
2029 ciBlock* ciblk = _methodBlocks->block_containing(bci);
2030 assert(ciblk->start_bci() == bci, "bad ciBlock boundaries");
2031 Block* block = get_block_for(ciblk->index(), jsrs, option);
2032
2033 assert(block == NULL? (option == no_create): block->is_backedge_copy() == (option == create_backedge_copy), "create option consistent with result");
2034
2035 if (CITraceTypeFlow) {
2036 if (block != NULL) {
2037 tty->print(">> Found block ");
2038 block->print_value_on(tty);
2039 tty->cr();
2040 } else {
2041 tty->print_cr(">> No such block.");
2042 }
2043 }
2044
2045 return block;
2046 }
2047
2048 // ------------------------------------------------------------------
2049 // ciTypeFlow::make_jsr_record
2050 //
2051 // Make a JsrRecord for a given (entry, return) pair, if such a record
2052 // does not already exist.
2053 ciTypeFlow::JsrRecord* ciTypeFlow::make_jsr_record(int entry_address,
2054 int return_address) {
2055 if (_jsr_records == NULL) {
2056 _jsr_records = new (arena()) GrowableArray<JsrRecord*>(arena(),
2057 _jsr_count,
2058 0,
2059 NULL);
2060 }
2061 JsrRecord* record = NULL;
2062 int len = _jsr_records->length();
2063 for (int i = 0; i < len; i++) {
2064 JsrRecord* record = _jsr_records->at(i);
2065 if (record->entry_address() == entry_address &&
2066 record->return_address() == return_address) {
2067 return record;
2068 }
2069 }
2070
2071 record = new (arena()) JsrRecord(entry_address, return_address);
2072 _jsr_records->append(record);
2073 return record;
2074 }
2075
2076 // ------------------------------------------------------------------
2077 // ciTypeFlow::flow_exceptions
2078 //
2079 // Merge the current state into all exceptional successors at the
2080 // current point in the code.
2081 void ciTypeFlow::flow_exceptions(GrowableArray<ciTypeFlow::Block*>* exceptions,
2082 GrowableArray<ciInstanceKlass*>* exc_klasses,
2083 ciTypeFlow::StateVector* state) {
2084 int len = exceptions->length();
2085 assert(exc_klasses->length() == len, "must have same length");
2086 for (int i = 0; i < len; i++) {
2087 Block* block = exceptions->at(i);
2088 ciInstanceKlass* exception_klass = exc_klasses->at(i);
2089
2090 if (!exception_klass->is_loaded()) {
2091 // Do not compile any code for unloaded exception types.
2092 // Following compiler passes are responsible for doing this also.
2093 continue;
2094 }
2095
2096 if (block->meet_exception(exception_klass, state)) {
2097 // Block was modified and has PO. Add it to the work list.
2098 if (block->has_post_order() &&
2099 !block->is_on_work_list()) {
2100 add_to_work_list(block);
2101 }
2102 }
2103 }
2104 }
2105
2106 // ------------------------------------------------------------------
2107 // ciTypeFlow::flow_successors
2108 //
2109 // Merge the current state into all successors at the current point
2110 // in the code.
2111 void ciTypeFlow::flow_successors(GrowableArray<ciTypeFlow::Block*>* successors,
2112 ciTypeFlow::StateVector* state) {
2113 int len = successors->length();
2114 for (int i = 0; i < len; i++) {
2115 Block* block = successors->at(i);
2116 if (block->meet(state)) {
2117 // Block was modified and has PO. Add it to the work list.
2118 if (block->has_post_order() &&
2119 !block->is_on_work_list()) {
2120 add_to_work_list(block);
2121 }
2122 }
2123 }
2124 }
2125
2126 // ------------------------------------------------------------------
2127 // ciTypeFlow::can_trap
2128 //
2129 // Tells if a given instruction is able to generate an exception edge.
2130 bool ciTypeFlow::can_trap(ciBytecodeStream& str) {
2131 // Cf. GenerateOopMap::do_exception_edge.
2132 if (!Bytecodes::can_trap(str.cur_bc())) return false;
2133
2134 switch (str.cur_bc()) {
2135 case Bytecodes::_ldc:
2136 case Bytecodes::_ldc_w:
2137 case Bytecodes::_ldc2_w:
2138 case Bytecodes::_aload_0:
2139 // These bytecodes can trap for rewriting. We need to assume that
2140 // they do not throw exceptions to make the monitor analysis work.
2141 return false;
2142
2143 case Bytecodes::_ireturn:
2144 case Bytecodes::_lreturn:
2145 case Bytecodes::_freturn:
2146 case Bytecodes::_dreturn:
2147 case Bytecodes::_areturn:
2148 case Bytecodes::_return:
2149 // We can assume the monitor stack is empty in this analysis.
2150 return false;
2151
2152 case Bytecodes::_monitorexit:
2153 // We can assume monitors are matched in this analysis.
2154 return false;
2155 }
2156
2157 return true;
2158 }
2159
2160 // ------------------------------------------------------------------
2161 // ciTypeFlow::clone_loop_heads
2162 //
2163 // Clone the loop heads
2164 bool ciTypeFlow::clone_loop_heads(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) {
2165 bool rslt = false;
2166 for (PreorderLoops iter(loop_tree_root()); !iter.done(); iter.next()) {
2167 lp = iter.current();
2168 Block* head = lp->head();
2169 if (lp == loop_tree_root() ||
2170 lp->is_irreducible() ||
2171 !head->is_clonable_exit(lp))
2172 continue;
2173
2174 // check not already cloned
2175 if (head->backedge_copy_count() != 0)
2176 continue;
2177
2178 // check _no_ shared head below us
2179 Loop* ch;
2180 for (ch = lp->child(); ch != NULL && ch->head() != head; ch = ch->sibling());
2181 if (ch != NULL)
2182 continue;
2183
2184 // Clone head
2185 Block* new_head = head->looping_succ(lp);
2186 Block* clone = clone_loop_head(lp, temp_vector, temp_set);
2187 // Update lp's info
2188 clone->set_loop(lp);
2189 lp->set_head(new_head);
2190 lp->set_tail(clone);
2191 // And move original head into outer loop
2192 head->set_loop(lp->parent());
2193
2194 rslt = true;
2195 }
2196 return rslt;
2197 }
2198
2199 // ------------------------------------------------------------------
2200 // ciTypeFlow::clone_loop_head
2201 //
2202 // Clone lp's head and replace tail's successors with clone.
2203 //
2204 // |
2205 // v
2206 // head <-> body
2207 // |
2208 // v
2209 // exit
2210 //
2211 // new_head
2212 //
2213 // |
2214 // v
2215 // head ----------\
2216 // | |
2217 // | v
2218 // | clone <-> body
2219 // | |
2220 // | /--/
2221 // | |
2222 // v v
2223 // exit
2224 //
2225 ciTypeFlow::Block* ciTypeFlow::clone_loop_head(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) {
2226 Block* head = lp->head();
2227 Block* tail = lp->tail();
2228 if (CITraceTypeFlow) {
2229 tty->print(">> Requesting clone of loop head "); head->print_value_on(tty);
2230 tty->print(" for predecessor "); tail->print_value_on(tty);
2231 tty->cr();
2232 }
2233 Block* clone = block_at(head->start(), head->jsrs(), create_backedge_copy);
2234 assert(clone->backedge_copy_count() == 1, "one backedge copy for all back edges");
2235
2236 assert(!clone->has_pre_order(), "just created");
2237 clone->set_next_pre_order();
2238
2239 // Insert clone after (orig) tail in reverse post order
2240 clone->set_rpo_next(tail->rpo_next());
2241 tail->set_rpo_next(clone);
2242
2243 // tail->head becomes tail->clone
2244 for (SuccIter iter(tail); !iter.done(); iter.next()) {
2245 if (iter.succ() == head) {
2246 iter.set_succ(clone);
2247 }
2248 }
2249 flow_block(tail, temp_vector, temp_set);
2250 if (head == tail) {
2251 // For self-loops, clone->head becomes clone->clone
2252 flow_block(clone, temp_vector, temp_set);
2253 for (SuccIter iter(clone); !iter.done(); iter.next()) {
2254 if (iter.succ() == head) {
2255 iter.set_succ(clone);
2256 break;
2257 }
2258 }
2259 }
2260 flow_block(clone, temp_vector, temp_set);
2261
2262 return clone;
2263 }
2264
2265 // ------------------------------------------------------------------
2266 // ciTypeFlow::flow_block
2267 //
2268 // Interpret the effects of the bytecodes on the incoming state
2269 // vector of a basic block. Push the changed state to succeeding
2270 // basic blocks.
2271 void ciTypeFlow::flow_block(ciTypeFlow::Block* block,
2272 ciTypeFlow::StateVector* state,
2273 ciTypeFlow::JsrSet* jsrs) {
2274 if (CITraceTypeFlow) {
2275 tty->print("\n>> ANALYZING BLOCK : ");
2276 tty->cr();
2277 block->print_on(tty);
2278 }
2279 assert(block->has_pre_order(), "pre-order is assigned before 1st flow");
2280
2281 int start = block->start();
2282 int limit = block->limit();
2283 int control = block->control();
2284 if (control != ciBlock::fall_through_bci) {
2285 limit = control;
2286 }
2287
2288 // Grab the state from the current block.
2289 block->copy_state_into(state);
2290 state->def_locals()->clear();
2291
2292 GrowableArray<Block*>* exceptions = block->exceptions();
2293 GrowableArray<ciInstanceKlass*>* exc_klasses = block->exc_klasses();
2294 bool has_exceptions = exceptions->length() > 0;
2295
2296 bool exceptions_used = false;
2297
2298 ciBytecodeStream str(method());
2299 str.reset_to_bci(start);
2300 Bytecodes::Code code;
2301 while ((code = str.next()) != ciBytecodeStream::EOBC() &&
2302 str.cur_bci() < limit) {
2303 // Check for exceptional control flow from this point.
2304 if (has_exceptions && can_trap(str)) {
2305 flow_exceptions(exceptions, exc_klasses, state);
2306 exceptions_used = true;
2307 }
2308 // Apply the effects of the current bytecode to our state.
2309 bool res = state->apply_one_bytecode(&str);
2310
2311 // Watch for bailouts.
2312 if (failing()) return;
2313
2314 if (res) {
2315
2316 // We have encountered a trap. Record it in this block.
2317 block->set_trap(state->trap_bci(), state->trap_index());
2318
2319 if (CITraceTypeFlow) {
2320 tty->print_cr(">> Found trap");
2321 block->print_on(tty);
2322 }
2323
2324 // Save set of locals defined in this block
2325 block->def_locals()->add(state->def_locals());
2326
2327 // Record (no) successors.
2328 block->successors(&str, state, jsrs);
2329
2330 assert(!has_exceptions || exceptions_used, "Not removing exceptions");
2331
2332 // Discontinue interpretation of this Block.
2333 return;
2334 }
2335 }
2336
2337 GrowableArray<Block*>* successors = NULL;
2338 if (control != ciBlock::fall_through_bci) {
2339 // Check for exceptional control flow from this point.
2340 if (has_exceptions && can_trap(str)) {
2341 flow_exceptions(exceptions, exc_klasses, state);
2342 exceptions_used = true;
2343 }
2344
2345 // Fix the JsrSet to reflect effect of the bytecode.
2346 block->copy_jsrs_into(jsrs);
2347 jsrs->apply_control(this, &str, state);
2348
2349 // Find successor edges based on old state and new JsrSet.
2350 successors = block->successors(&str, state, jsrs);
2351
2352 // Apply the control changes to the state.
2353 state->apply_one_bytecode(&str);
2354 } else {
2355 // Fall through control
2356 successors = block->successors(&str, NULL, NULL);
2357 }
2358
2359 // Save set of locals defined in this block
2360 block->def_locals()->add(state->def_locals());
2361
2362 // Remove untaken exception paths
2363 if (!exceptions_used)
2364 exceptions->clear();
2365
2366 // Pass our state to successors.
2367 flow_successors(successors, state);
2368 }
2369
2370 // ------------------------------------------------------------------
2371 // ciTypeFlow::PostOrderLoops::next
2372 //
2373 // Advance to next loop tree using a postorder, left-to-right traversal.
2374 void ciTypeFlow::PostorderLoops::next() {
2375 assert(!done(), "must not be done.");
2376 if (_current->sibling() != NULL) {
2377 _current = _current->sibling();
2378 while (_current->child() != NULL) {
2379 _current = _current->child();
2380 }
2381 } else {
2382 _current = _current->parent();
2383 }
2384 }
2385
2386 // ------------------------------------------------------------------
2387 // ciTypeFlow::PreOrderLoops::next
2388 //
2389 // Advance to next loop tree using a preorder, left-to-right traversal.
2390 void ciTypeFlow::PreorderLoops::next() {
2391 assert(!done(), "must not be done.");
2392 if (_current->child() != NULL) {
2393 _current = _current->child();
2394 } else if (_current->sibling() != NULL) {
2395 _current = _current->sibling();
2396 } else {
2397 while (_current != _root && _current->sibling() == NULL) {
2398 _current = _current->parent();
2399 }
2400 if (_current == _root) {
2401 _current = NULL;
2402 assert(done(), "must be done.");
2403 } else {
2404 assert(_current->sibling() != NULL, "must be more to do");
2405 _current = _current->sibling();
2406 }
2407 }
2408 }
2409
2410 // ------------------------------------------------------------------
2411 // ciTypeFlow::Loop::sorted_merge
2412 //
2413 // Merge the branch lp into this branch, sorting on the loop head
2414 // pre_orders. Returns the leaf of the merged branch.
2415 // Child and sibling pointers will be setup later.
2416 // Sort is (looking from leaf towards the root)
2417 // descending on primary key: loop head's pre_order, and
2418 // ascending on secondary key: loop tail's pre_order.
2419 ciTypeFlow::Loop* ciTypeFlow::Loop::sorted_merge(Loop* lp) {
2420 Loop* leaf = this;
2421 Loop* prev = NULL;
2422 Loop* current = leaf;
2423 while (lp != NULL) {
2424 int lp_pre_order = lp->head()->pre_order();
2425 // Find insertion point for "lp"
2426 while (current != NULL) {
2427 if (current == lp)
2428 return leaf; // Already in list
2429 if (current->head()->pre_order() < lp_pre_order)
2430 break;
2431 if (current->head()->pre_order() == lp_pre_order &&
2432 current->tail()->pre_order() > lp->tail()->pre_order()) {
2433 break;
2434 }
2435 prev = current;
2436 current = current->parent();
2437 }
2438 Loop* next_lp = lp->parent(); // Save future list of items to insert
2439 // Insert lp before current
2440 lp->set_parent(current);
2441 if (prev != NULL) {
2442 prev->set_parent(lp);
2443 } else {
2444 leaf = lp;
2445 }
2446 prev = lp; // Inserted item is new prev[ious]
2447 lp = next_lp; // Next item to insert
2448 }
2449 return leaf;
2450 }
2451
2452 // ------------------------------------------------------------------
2453 // ciTypeFlow::build_loop_tree
2454 //
2455 // Incrementally build loop tree.
2456 void ciTypeFlow::build_loop_tree(Block* blk) {
2457 assert(!blk->is_post_visited(), "precondition");
2458 Loop* innermost = NULL; // merge of loop tree branches over all successors
2459
2460 for (SuccIter iter(blk); !iter.done(); iter.next()) {
2461 Loop* lp = NULL;
2462 Block* succ = iter.succ();
2463 if (!succ->is_post_visited()) {
2464 // Found backedge since predecessor post visited, but successor is not
2465 assert(succ->pre_order() <= blk->pre_order(), "should be backedge");
2466
2467 // Create a LoopNode to mark this loop.
2468 lp = new (arena()) Loop(succ, blk);
2469 if (succ->loop() == NULL)
2470 succ->set_loop(lp);
2471 // succ->loop will be updated to innermost loop on a later call, when blk==succ
2472
2473 } else { // Nested loop
2474 lp = succ->loop();
2475
2476 // If succ is loop head, find outer loop.
2477 while (lp != NULL && lp->head() == succ) {
2478 lp = lp->parent();
2479 }
2480 if (lp == NULL) {
2481 // Infinite loop, it's parent is the root
2482 lp = loop_tree_root();
2483 }
2484 }
2485
2486 // Check for irreducible loop.
2487 // Successor has already been visited. If the successor's loop head
2488 // has already been post-visited, then this is another entry into the loop.
2489 while (lp->head()->is_post_visited() && lp != loop_tree_root()) {
2490 _has_irreducible_entry = true;
2491 lp->set_irreducible(succ);
2492 if (!succ->is_on_work_list()) {
2493 // Assume irreducible entries need more data flow
2494 add_to_work_list(succ);
2495 }
2496 Loop* plp = lp->parent();
2497 if (plp == NULL) {
2498 // This only happens for some irreducible cases. The parent
2499 // will be updated during a later pass.
2500 break;
2501 }
2502 lp = plp;
2503 }
2504
2505 // Merge loop tree branch for all successors.
2506 innermost = innermost == NULL ? lp : innermost->sorted_merge(lp);
2507
2508 } // end loop
2509
2510 if (innermost == NULL) {
2511 assert(blk->successors()->length() == 0, "CFG exit");
2512 blk->set_loop(loop_tree_root());
2513 } else if (innermost->head() == blk) {
2514 // If loop header, complete the tree pointers
2515 if (blk->loop() != innermost) {
2516 #if ASSERT
2517 assert(blk->loop()->head() == innermost->head(), "same head");
2518 Loop* dl;
2519 for (dl = innermost; dl != NULL && dl != blk->loop(); dl = dl->parent());
2520 assert(dl == blk->loop(), "blk->loop() already in innermost list");
2521 #endif
2522 blk->set_loop(innermost);
2523 }
2524 innermost->def_locals()->add(blk->def_locals());
2525 Loop* l = innermost;
2526 Loop* p = l->parent();
2527 while (p && l->head() == blk) {
2528 l->set_sibling(p->child()); // Put self on parents 'next child'
2529 p->set_child(l); // Make self the first child of parent
2530 p->def_locals()->add(l->def_locals());
2531 l = p; // Walk up the parent chain
2532 p = l->parent();
2533 }
2534 } else {
2535 blk->set_loop(innermost);
2536 innermost->def_locals()->add(blk->def_locals());
2537 }
2538 }
2539
2540 // ------------------------------------------------------------------
2541 // ciTypeFlow::Loop::contains
2542 //
2543 // Returns true if lp is nested loop.
2544 bool ciTypeFlow::Loop::contains(ciTypeFlow::Loop* lp) const {
2545 assert(lp != NULL, "");
2546 if (this == lp || head() == lp->head()) return true;
2547 int depth1 = depth();
2548 int depth2 = lp->depth();
2549 if (depth1 > depth2)
2550 return false;
2551 while (depth1 < depth2) {
2552 depth2--;
2553 lp = lp->parent();
2554 }
2555 return this == lp;
2556 }
2557
2558 // ------------------------------------------------------------------
2559 // ciTypeFlow::Loop::depth
2560 //
2561 // Loop depth
2562 int ciTypeFlow::Loop::depth() const {
2563 int dp = 0;
2564 for (Loop* lp = this->parent(); lp != NULL; lp = lp->parent())
2565 dp++;
2566 return dp;
2567 }
2568
2569 #ifndef PRODUCT
2570 // ------------------------------------------------------------------
2571 // ciTypeFlow::Loop::print
2572 void ciTypeFlow::Loop::print(outputStream* st, int indent) const {
2573 for (int i = 0; i < indent; i++) st->print(" ");
2574 st->print("%d<-%d %s",
2575 is_root() ? 0 : this->head()->pre_order(),
2576 is_root() ? 0 : this->tail()->pre_order(),
2577 is_irreducible()?" irr":"");
2578 st->print(" defs: ");
2579 def_locals()->print_on(st, _head->outer()->method()->max_locals());
2580 st->cr();
2581 for (Loop* ch = child(); ch != NULL; ch = ch->sibling())
2582 ch->print(st, indent+2);
2583 }
2584 #endif
2585
2586 // ------------------------------------------------------------------
2587 // ciTypeFlow::df_flow_types
2588 //
2589 // Perform the depth first type flow analysis. Helper for flow_types.
2590 void ciTypeFlow::df_flow_types(Block* start,
2591 bool do_flow,
2592 StateVector* temp_vector,
2593 JsrSet* temp_set) {
2594 int dft_len = 100;
2595 GrowableArray<Block*> stk(arena(), dft_len, 0, NULL);
2596
2597 ciBlock* dummy = _methodBlocks->make_dummy_block();
2598 JsrSet* root_set = new JsrSet(NULL, 0);
2599 Block* root_head = new (arena()) Block(this, dummy, root_set);
2600 Block* root_tail = new (arena()) Block(this, dummy, root_set);
2601 root_head->set_pre_order(0);
2602 root_head->set_post_order(0);
2603 root_tail->set_pre_order(max_jint);
2604 root_tail->set_post_order(max_jint);
2605 set_loop_tree_root(new (arena()) Loop(root_head, root_tail));
2606
2607 stk.push(start);
2608
2609 _next_pre_order = 0; // initialize pre_order counter
2610 _rpo_list = NULL;
2611 int next_po = 0; // initialize post_order counter
2612
2613 // Compute RPO and the control flow graph
2614 int size;
2615 while ((size = stk.length()) > 0) {
2616 Block* blk = stk.top(); // Leave node on stack
2617 if (!blk->is_visited()) {
2618 // forward arc in graph
2619 assert (!blk->has_pre_order(), "");
2620 blk->set_next_pre_order();
2621
2622 if (_next_pre_order >= MaxNodeLimit / 2) {
2623 // Too many basic blocks. Bail out.
2624 // This can happen when try/finally constructs are nested to depth N,
2625 // and there is O(2**N) cloning of jsr bodies. See bug 4697245!
2626 // "MaxNodeLimit / 2" is used because probably the parser will
2627 // generate at least twice that many nodes and bail out.
2628 record_failure("too many basic blocks");
2629 return;
2630 }
2631 if (do_flow) {
2632 flow_block(blk, temp_vector, temp_set);
2633 if (failing()) return; // Watch for bailouts.
2634 }
2635 } else if (!blk->is_post_visited()) {
2636 // cross or back arc
2637 for (SuccIter iter(blk); !iter.done(); iter.next()) {
2638 Block* succ = iter.succ();
2639 if (!succ->is_visited()) {
2640 stk.push(succ);
2641 }
2642 }
2643 if (stk.length() == size) {
2644 // There were no additional children, post visit node now
2645 stk.pop(); // Remove node from stack
2646
2647 build_loop_tree(blk);
2648 blk->set_post_order(next_po++); // Assign post order
2649 prepend_to_rpo_list(blk);
2650 assert(blk->is_post_visited(), "");
2651
2652 if (blk->is_loop_head() && !blk->is_on_work_list()) {
2653 // Assume loop heads need more data flow
2654 add_to_work_list(blk);
2655 }
2656 }
2657 } else {
2658 stk.pop(); // Remove post-visited node from stack
2659 }
2660 }
2661 }
2662
2663 // ------------------------------------------------------------------
2664 // ciTypeFlow::flow_types
2665 //
2666 // Perform the type flow analysis, creating and cloning Blocks as
2667 // necessary.
2668 void ciTypeFlow::flow_types() {
2669 ResourceMark rm;
2670 StateVector* temp_vector = new StateVector(this);
2671 JsrSet* temp_set = new JsrSet(NULL, 16);
2672
2673 // Create the method entry block.
2674 Block* start = block_at(start_bci(), temp_set);
2675
2676 // Load the initial state into it.
2677 const StateVector* start_state = get_start_state();
2678 if (failing()) return;
2679 start->meet(start_state);
2680
2681 // Depth first visit
2682 df_flow_types(start, true /*do flow*/, temp_vector, temp_set);
2683
2684 if (failing()) return;
2685 assert(_rpo_list == start, "must be start");
2686
2687 // Any loops found?
2688 if (loop_tree_root()->child() != NULL &&
2689 env()->comp_level() >= CompLevel_full_optimization) {
2690 // Loop optimizations are not performed on Tier1 compiles.
2691
2692 bool changed = clone_loop_heads(loop_tree_root(), temp_vector, temp_set);
2693
2694 // If some loop heads were cloned, recompute postorder and loop tree
2695 if (changed) {
2696 loop_tree_root()->set_child(NULL);
2697 for (Block* blk = _rpo_list; blk != NULL;) {
2698 Block* next = blk->rpo_next();
2699 blk->df_init();
2700 blk = next;
2701 }
2702 df_flow_types(start, false /*no flow*/, temp_vector, temp_set);
2703 }
2704 }
2705
2706 if (CITraceTypeFlow) {
2707 tty->print_cr("\nLoop tree");
2708 loop_tree_root()->print();
2709 }
2710
2711 // Continue flow analysis until fixed point reached
2712
2713 debug_only(int max_block = _next_pre_order;)
2714
2715 while (!work_list_empty()) {
2716 Block* blk = work_list_next();
2717 assert (blk->has_post_order(), "post order assigned above");
2718
2719 flow_block(blk, temp_vector, temp_set);
2720
2721 assert (max_block == _next_pre_order, "no new blocks");
2722 assert (!failing(), "no more bailouts");
2723 }
2724 }
2725
2726 // ------------------------------------------------------------------
2727 // ciTypeFlow::map_blocks
2728 //
2729 // Create the block map, which indexes blocks in reverse post-order.
2730 void ciTypeFlow::map_blocks() {
2731 assert(_block_map == NULL, "single initialization");
2732 int block_ct = _next_pre_order;
2733 _block_map = NEW_ARENA_ARRAY(arena(), Block*, block_ct);
2734 assert(block_ct == block_count(), "");
2735
2736 Block* blk = _rpo_list;
2737 for (int m = 0; m < block_ct; m++) {
2738 int rpo = blk->rpo();
2739 assert(rpo == m, "should be sequential");
2740 _block_map[rpo] = blk;
2741 blk = blk->rpo_next();
2742 }
2743 assert(blk == NULL, "should be done");
2744
2745 for (int j = 0; j < block_ct; j++) {
2746 assert(_block_map[j] != NULL, "must not drop any blocks");
2747 Block* block = _block_map[j];
2748 // Remove dead blocks from successor lists:
2749 for (int e = 0; e <= 1; e++) {
2750 GrowableArray<Block*>* l = e? block->exceptions(): block->successors();
2751 for (int k = 0; k < l->length(); k++) {
2752 Block* s = l->at(k);
2753 if (!s->has_post_order()) {
2754 if (CITraceTypeFlow) {
2755 tty->print("Removing dead %s successor of #%d: ", (e? "exceptional": "normal"), block->pre_order());
2756 s->print_value_on(tty);
2757 tty->cr();
2758 }
2759 l->remove(s);
2760 --k;
2761 }
2762 }
2763 }
2764 }
2765 }
2766
2767 // ------------------------------------------------------------------
2768 // ciTypeFlow::get_block_for
2769 //
2770 // Find a block with this ciBlock which has a compatible JsrSet.
2771 // If no such block exists, create it, unless the option is no_create.
2772 // If the option is create_backedge_copy, always create a fresh backedge copy.
2773 ciTypeFlow::Block* ciTypeFlow::get_block_for(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
2774 Arena* a = arena();
2775 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
2776 if (blocks == NULL) {
2777 // Query only?
2778 if (option == no_create) return NULL;
2779
2780 // Allocate the growable array.
2781 blocks = new (a) GrowableArray<Block*>(a, 4, 0, NULL);
2782 _idx_to_blocklist[ciBlockIndex] = blocks;
2783 }
2784
2785 if (option != create_backedge_copy) {
2786 int len = blocks->length();
2787 for (int i = 0; i < len; i++) {
2788 Block* block = blocks->at(i);
2789 if (!block->is_backedge_copy() && block->is_compatible_with(jsrs)) {
2790 return block;
2791 }
2792 }
2793 }
2794
2795 // Query only?
2796 if (option == no_create) return NULL;
2797
2798 // We did not find a compatible block. Create one.
2799 Block* new_block = new (a) Block(this, _methodBlocks->block(ciBlockIndex), jsrs);
2800 if (option == create_backedge_copy) new_block->set_backedge_copy(true);
2801 blocks->append(new_block);
2802 return new_block;
2803 }
2804
2805 // ------------------------------------------------------------------
2806 // ciTypeFlow::backedge_copy_count
2807 //
2808 int ciTypeFlow::backedge_copy_count(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs) const {
2809 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
2810
2811 if (blocks == NULL) {
2812 return 0;
2813 }
2814
2815 int count = 0;
2816 int len = blocks->length();
2817 for (int i = 0; i < len; i++) {
2818 Block* block = blocks->at(i);
2819 if (block->is_backedge_copy() && block->is_compatible_with(jsrs)) {
2820 count++;
2821 }
2822 }
2823
2824 return count;
2825 }
2826
2827 // ------------------------------------------------------------------
2828 // ciTypeFlow::do_flow
2829 //
2830 // Perform type inference flow analysis.
2831 void ciTypeFlow::do_flow() {
2832 if (CITraceTypeFlow) {
2833 tty->print_cr("\nPerforming flow analysis on method");
2834 method()->print();
2835 if (is_osr_flow()) tty->print(" at OSR bci %d", start_bci());
2836 tty->cr();
2837 method()->print_codes();
2838 }
2839 if (CITraceTypeFlow) {
2840 tty->print_cr("Initial CI Blocks");
2841 print_on(tty);
2842 }
2843 flow_types();
2844 // Watch for bailouts.
2845 if (failing()) {
2846 return;
2847 }
2848
2849 map_blocks();
2850
2851 if (CIPrintTypeFlow || CITraceTypeFlow) {
2852 rpo_print_on(tty);
2853 }
2854 }
2855
2856 // ------------------------------------------------------------------
2857 // ciTypeFlow::record_failure()
2858 // The ciTypeFlow object keeps track of failure reasons separately from the ciEnv.
2859 // This is required because there is not a 1-1 relation between the ciEnv and
2860 // the TypeFlow passes within a compilation task. For example, if the compiler
2861 // is considering inlining a method, it will request a TypeFlow. If that fails,
2862 // the compilation as a whole may continue without the inlining. Some TypeFlow
2863 // requests are not optional; if they fail the requestor is responsible for
2864 // copying the failure reason up to the ciEnv. (See Parse::Parse.)
2865 void ciTypeFlow::record_failure(const char* reason) {
2866 if (env()->log() != NULL) {
2867 env()->log()->elem("failure reason='%s' phase='typeflow'", reason);
2868 }
2869 if (_failure_reason == NULL) {
2870 // Record the first failure reason.
2871 _failure_reason = reason;
2872 }
2873 }
2874
2875 #ifndef PRODUCT
2876 // ------------------------------------------------------------------
2877 // ciTypeFlow::print_on
2878 void ciTypeFlow::print_on(outputStream* st) const {
2879 // Walk through CI blocks
2880 st->print_cr("********************************************************");
2881 st->print ("TypeFlow for ");
2882 method()->name()->print_symbol_on(st);
2883 int limit_bci = code_size();
2884 st->print_cr(" %d bytes", limit_bci);
2885 ciMethodBlocks *mblks = _methodBlocks;
2886 ciBlock* current = NULL;
2887 for (int bci = 0; bci < limit_bci; bci++) {
2888 ciBlock* blk = mblks->block_containing(bci);
2889 if (blk != NULL && blk != current) {
2890 current = blk;
2891 current->print_on(st);
2892
2893 GrowableArray<Block*>* blocks = _idx_to_blocklist[blk->index()];
2894 int num_blocks = (blocks == NULL) ? 0 : blocks->length();
2895
2896 if (num_blocks == 0) {
2897 st->print_cr(" No Blocks");
2898 } else {
2899 for (int i = 0; i < num_blocks; i++) {
2900 Block* block = blocks->at(i);
2901 block->print_on(st);
2902 }
2903 }
2904 st->print_cr("--------------------------------------------------------");
2905 st->cr();
2906 }
2907 }
2908 st->print_cr("********************************************************");
2909 st->cr();
2910 }
2911
2912 void ciTypeFlow::rpo_print_on(outputStream* st) const {
2913 st->print_cr("********************************************************");
2914 st->print ("TypeFlow for ");
2915 method()->name()->print_symbol_on(st);
2916 int limit_bci = code_size();
2917 st->print_cr(" %d bytes", limit_bci);
2918 for (Block* blk = _rpo_list; blk != NULL; blk = blk->rpo_next()) {
2919 blk->print_on(st);
2920 st->print_cr("--------------------------------------------------------");
2921 st->cr();
2922 }
2923 st->print_cr("********************************************************");
2924 st->cr();
2925 }
2926 #endif