1 /*
2 * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
24
25 #include "precompiled.hpp"
26 #include "ci/ciConstant.hpp"
27 #include "ci/ciField.hpp"
28 #include "ci/ciMethod.hpp"
29 #include "ci/ciMethodData.hpp"
30 #include "ci/ciObjArrayKlass.hpp"
31 #include "ci/ciStreams.hpp"
32 #include "ci/ciTypeArrayKlass.hpp"
33 #include "ci/ciTypeFlow.hpp"
34 #include "ci/ciValueKlass.hpp"
35 #include "compiler/compileLog.hpp"
36 #include "interpreter/bytecode.hpp"
37 #include "interpreter/bytecodes.hpp"
38 #include "memory/allocation.inline.hpp"
39 #include "memory/resourceArea.hpp"
40 #include "oops/oop.inline.hpp"
41 #include "opto/compile.hpp"
42 #include "opto/node.hpp"
43 #include "runtime/deoptimization.hpp"
44 #include "utilities/growableArray.hpp"
45
46 // ciTypeFlow::JsrSet
47 //
48 // A JsrSet represents some set of JsrRecords. This class
49 // is used to record a set of all jsr routines which we permit
50 // execution to return (ret) from.
51 //
52 // During abstract interpretation, JsrSets are used to determine
53 // whether two paths which reach a given block are unique, and
54 // should be cloned apart, or are compatible, and should merge
55 // together.
56
57 // ------------------------------------------------------------------
58 // ciTypeFlow::JsrSet::JsrSet
59 ciTypeFlow::JsrSet::JsrSet(Arena* arena, int default_len) {
60 if (arena != NULL) {
61 // Allocate growable array in Arena.
62 _set = new (arena) GrowableArray<JsrRecord*>(arena, default_len, 0, NULL);
63 } else {
64 // Allocate growable array in current ResourceArea.
65 _set = new GrowableArray<JsrRecord*>(4, 0, NULL, false);
66 }
67 }
68
69 // ------------------------------------------------------------------
70 // ciTypeFlow::JsrSet::copy_into
71 void ciTypeFlow::JsrSet::copy_into(JsrSet* jsrs) {
72 int len = size();
73 jsrs->_set->clear();
74 for (int i = 0; i < len; i++) {
75 jsrs->_set->append(_set->at(i));
76 }
77 }
78
79 // ------------------------------------------------------------------
80 // ciTypeFlow::JsrSet::is_compatible_with
81 //
82 // !!!! MISGIVINGS ABOUT THIS... disregard
83 //
84 // Is this JsrSet compatible with some other JsrSet?
85 //
86 // In set-theoretic terms, a JsrSet can be viewed as a partial function
87 // from entry addresses to return addresses. Two JsrSets A and B are
88 // compatible iff
89 //
90 // For any x,
91 // A(x) defined and B(x) defined implies A(x) == B(x)
92 //
93 // Less formally, two JsrSets are compatible when they have identical
94 // return addresses for any entry addresses they share in common.
95 bool ciTypeFlow::JsrSet::is_compatible_with(JsrSet* other) {
96 // Walk through both sets in parallel. If the same entry address
97 // appears in both sets, then the return address must match for
98 // the sets to be compatible.
99 int size1 = size();
100 int size2 = other->size();
101
102 // Special case. If nothing is on the jsr stack, then there can
103 // be no ret.
104 if (size2 == 0) {
105 return true;
106 } else if (size1 != size2) {
107 return false;
108 } else {
109 for (int i = 0; i < size1; i++) {
110 JsrRecord* record1 = record_at(i);
111 JsrRecord* record2 = other->record_at(i);
112 if (record1->entry_address() != record2->entry_address() ||
113 record1->return_address() != record2->return_address()) {
114 return false;
115 }
116 }
117 return true;
118 }
119
120 #if 0
121 int pos1 = 0;
122 int pos2 = 0;
123 int size1 = size();
124 int size2 = other->size();
125 while (pos1 < size1 && pos2 < size2) {
126 JsrRecord* record1 = record_at(pos1);
127 JsrRecord* record2 = other->record_at(pos2);
128 int entry1 = record1->entry_address();
129 int entry2 = record2->entry_address();
130 if (entry1 < entry2) {
131 pos1++;
132 } else if (entry1 > entry2) {
133 pos2++;
134 } else {
135 if (record1->return_address() == record2->return_address()) {
136 pos1++;
137 pos2++;
138 } else {
139 // These two JsrSets are incompatible.
140 return false;
141 }
142 }
143 }
144 // The two JsrSets agree.
145 return true;
146 #endif
147 }
148
149 // ------------------------------------------------------------------
150 // ciTypeFlow::JsrSet::insert_jsr_record
151 //
152 // Insert the given JsrRecord into the JsrSet, maintaining the order
153 // of the set and replacing any element with the same entry address.
154 void ciTypeFlow::JsrSet::insert_jsr_record(JsrRecord* record) {
155 int len = size();
156 int entry = record->entry_address();
157 int pos = 0;
158 for ( ; pos < len; pos++) {
159 JsrRecord* current = record_at(pos);
160 if (entry == current->entry_address()) {
161 // Stomp over this entry.
162 _set->at_put(pos, record);
163 assert(size() == len, "must be same size");
164 return;
165 } else if (entry < current->entry_address()) {
166 break;
167 }
168 }
169
170 // Insert the record into the list.
171 JsrRecord* swap = record;
172 JsrRecord* temp = NULL;
173 for ( ; pos < len; pos++) {
174 temp = _set->at(pos);
175 _set->at_put(pos, swap);
176 swap = temp;
177 }
178 _set->append(swap);
179 assert(size() == len+1, "must be larger");
180 }
181
182 // ------------------------------------------------------------------
183 // ciTypeFlow::JsrSet::remove_jsr_record
184 //
185 // Remove the JsrRecord with the given return address from the JsrSet.
186 void ciTypeFlow::JsrSet::remove_jsr_record(int return_address) {
187 int len = size();
188 for (int i = 0; i < len; i++) {
189 if (record_at(i)->return_address() == return_address) {
190 // We have found the proper entry. Remove it from the
191 // JsrSet and exit.
192 for (int j = i+1; j < len ; j++) {
193 _set->at_put(j-1, _set->at(j));
194 }
195 _set->trunc_to(len-1);
196 assert(size() == len-1, "must be smaller");
197 return;
198 }
199 }
200 assert(false, "verify: returning from invalid subroutine");
201 }
202
203 // ------------------------------------------------------------------
204 // ciTypeFlow::JsrSet::apply_control
205 //
206 // Apply the effect of a control-flow bytecode on the JsrSet. The
207 // only bytecodes that modify the JsrSet are jsr and ret.
208 void ciTypeFlow::JsrSet::apply_control(ciTypeFlow* analyzer,
209 ciBytecodeStream* str,
210 ciTypeFlow::StateVector* state) {
211 Bytecodes::Code code = str->cur_bc();
212 if (code == Bytecodes::_jsr) {
213 JsrRecord* record =
214 analyzer->make_jsr_record(str->get_dest(), str->next_bci());
215 insert_jsr_record(record);
216 } else if (code == Bytecodes::_jsr_w) {
217 JsrRecord* record =
218 analyzer->make_jsr_record(str->get_far_dest(), str->next_bci());
219 insert_jsr_record(record);
220 } else if (code == Bytecodes::_ret) {
221 Cell local = state->local(str->get_index());
222 ciType* return_address = state->type_at(local);
223 assert(return_address->is_return_address(), "verify: wrong type");
224 if (size() == 0) {
225 // Ret-state underflow: Hit a ret w/o any previous jsrs. Bail out.
226 // This can happen when a loop is inside a finally clause (4614060).
227 analyzer->record_failure("OSR in finally clause");
228 return;
229 }
230 remove_jsr_record(return_address->as_return_address()->bci());
231 }
232 }
233
234 #ifndef PRODUCT
235 // ------------------------------------------------------------------
236 // ciTypeFlow::JsrSet::print_on
237 void ciTypeFlow::JsrSet::print_on(outputStream* st) const {
238 st->print("{ ");
239 int num_elements = size();
240 if (num_elements > 0) {
241 int i = 0;
242 for( ; i < num_elements - 1; i++) {
243 _set->at(i)->print_on(st);
244 st->print(", ");
245 }
246 _set->at(i)->print_on(st);
247 st->print(" ");
248 }
249 st->print("}");
250 }
251 #endif
252
253 // ciTypeFlow::StateVector
254 //
255 // A StateVector summarizes the type information at some point in
256 // the program.
257
258 // ------------------------------------------------------------------
259 // ciTypeFlow::StateVector::type_meet
260 //
261 // Meet two types.
262 //
263 // The semi-lattice of types use by this analysis are modeled on those
264 // of the verifier. The lattice is as follows:
265 //
266 // top_type() >= all non-extremal types >= bottom_type
267 // and
268 // Every primitive type is comparable only with itself. The meet of
269 // reference types is determined by their kind: instance class,
270 // interface, or array class. The meet of two types of the same
271 // kind is their least common ancestor. The meet of two types of
272 // different kinds is always java.lang.Object.
273 ciType* ciTypeFlow::StateVector::type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer) {
274 assert(t1 != t2, "checked in caller");
275 if (t1->equals(top_type())) {
276 return t2;
277 } else if (t2->equals(top_type())) {
278 return t1;
279 } else if (t1->is_primitive_type() || t2->is_primitive_type()) {
280 // Special case null_type. null_type meet any reference type T
281 // is T. null_type meet null_type is null_type.
282 if (t1->equals(null_type())) {
283 if (!t2->is_primitive_type() || t2->equals(null_type())) {
284 return t2;
285 }
286 } else if (t2->equals(null_type())) {
287 if (!t1->is_primitive_type()) {
288 return t1;
289 }
290 }
291
292 // At least one of the two types is a non-top primitive type.
293 // The other type is not equal to it. Fall to bottom.
294 return bottom_type();
295 } else {
296 // Both types are non-top non-primitive types. That is,
297 // both types are either instanceKlasses or arrayKlasses.
298 ciKlass* object_klass = analyzer->env()->Object_klass();
299 ciKlass* k1 = t1->as_klass();
300 ciKlass* k2 = t2->as_klass();
301 if (k1->equals(object_klass) || k2->equals(object_klass)) {
302 return object_klass;
303 } else if (!k1->is_loaded() || !k2->is_loaded()) {
304 // Unloaded classes fall to java.lang.Object at a merge.
305 return object_klass;
306 } else if (k1->is_interface() != k2->is_interface()) {
307 // When an interface meets a non-interface, we get Object;
308 // This is what the verifier does.
309 return object_klass;
310 } else if (k1->is_array_klass() || k2->is_array_klass()) {
311 // When an array meets a non-array, we get Object.
312 // When objArray meets typeArray, we also get Object.
313 // And when typeArray meets different typeArray, we again get Object.
314 // But when objArray meets objArray, we look carefully at element types.
315 if (k1->is_obj_array_klass() && k2->is_obj_array_klass()) {
316 // Meet the element types, then construct the corresponding array type.
317 ciKlass* elem1 = k1->as_obj_array_klass()->element_klass();
318 ciKlass* elem2 = k2->as_obj_array_klass()->element_klass();
319 ciKlass* elem = type_meet_internal(elem1, elem2, analyzer)->as_klass();
320 // Do an easy shortcut if one type is a super of the other.
321 if (elem == elem1) {
322 assert(k1 == ciObjArrayKlass::make(elem), "shortcut is OK");
323 return k1;
324 } else if (elem == elem2) {
325 assert(k2 == ciObjArrayKlass::make(elem), "shortcut is OK");
326 return k2;
327 } else {
328 return ciObjArrayKlass::make(elem);
329 }
330 } else {
331 return object_klass;
332 }
333 } else {
334 // Must be two plain old instance klasses.
335 assert(k1->is_instance_klass(), "previous cases handle non-instances");
336 assert(k2->is_instance_klass(), "previous cases handle non-instances");
337 return k1->least_common_ancestor(k2);
338 }
339 }
340 }
341
342
343 // ------------------------------------------------------------------
344 // ciTypeFlow::StateVector::StateVector
345 //
346 // Build a new state vector
347 ciTypeFlow::StateVector::StateVector(ciTypeFlow* analyzer) {
348 _outer = analyzer;
349 _stack_size = -1;
350 _monitor_count = -1;
351 // Allocate the _types array
352 int max_cells = analyzer->max_cells();
353 _types = (ciType**)analyzer->arena()->Amalloc(sizeof(ciType*) * max_cells);
354 for (int i=0; i<max_cells; i++) {
355 _types[i] = top_type();
356 }
357 _trap_bci = -1;
358 _trap_index = 0;
359 _def_locals.clear();
360 }
361
362
363 // ------------------------------------------------------------------
364 // ciTypeFlow::get_start_state
365 //
366 // Set this vector to the method entry state.
367 const ciTypeFlow::StateVector* ciTypeFlow::get_start_state() {
368 StateVector* state = new StateVector(this);
369 if (is_osr_flow()) {
370 ciTypeFlow* non_osr_flow = method()->get_flow_analysis();
371 if (non_osr_flow->failing()) {
372 record_failure(non_osr_flow->failure_reason());
373 return NULL;
374 }
375 JsrSet* jsrs = new JsrSet(NULL, 16);
376 Block* non_osr_block = non_osr_flow->existing_block_at(start_bci(), jsrs);
377 if (non_osr_block == NULL) {
378 record_failure("cannot reach OSR point");
379 return NULL;
380 }
381 // load up the non-OSR state at this point
382 non_osr_block->copy_state_into(state);
383 int non_osr_start = non_osr_block->start();
384 if (non_osr_start != start_bci()) {
385 // must flow forward from it
386 if (CITraceTypeFlow) {
387 tty->print_cr(">> Interpreting pre-OSR block %d:", non_osr_start);
388 }
389 Block* block = block_at(non_osr_start, jsrs);
390 assert(block->limit() == start_bci(), "must flow forward to start");
391 flow_block(block, state, jsrs);
392 }
393 return state;
394 // Note: The code below would be an incorrect for an OSR flow,
395 // even if it were possible for an OSR entry point to be at bci zero.
396 }
397 // "Push" the method signature into the first few locals.
398 state->set_stack_size(-max_locals());
399 if (!method()->is_static()) {
400 state->push(method()->holder());
401 assert(state->tos() == state->local(0), "");
402 }
403 for (ciSignatureStream str(method()->signature());
404 !str.at_return_type();
405 str.next()) {
406 state->push_translate(str.type());
407 }
408 // Set the rest of the locals to bottom.
409 Cell cell = state->next_cell(state->tos());
410 state->set_stack_size(0);
411 int limit = state->limit_cell();
412 for (; cell < limit; cell = state->next_cell(cell)) {
413 state->set_type_at(cell, state->bottom_type());
414 }
415 // Lock an object, if necessary.
416 state->set_monitor_count(method()->is_synchronized() ? 1 : 0);
417 return state;
418 }
419
420 // ------------------------------------------------------------------
421 // ciTypeFlow::StateVector::copy_into
422 //
423 // Copy our value into some other StateVector
424 void ciTypeFlow::StateVector::copy_into(ciTypeFlow::StateVector* copy)
425 const {
426 copy->set_stack_size(stack_size());
427 copy->set_monitor_count(monitor_count());
428 Cell limit = limit_cell();
429 for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
430 copy->set_type_at(c, type_at(c));
431 }
432 }
433
434 // ------------------------------------------------------------------
435 // ciTypeFlow::StateVector::meet
436 //
437 // Meets this StateVector with another, destructively modifying this
438 // one. Returns true if any modification takes place.
439 bool ciTypeFlow::StateVector::meet(const ciTypeFlow::StateVector* incoming) {
440 if (monitor_count() == -1) {
441 set_monitor_count(incoming->monitor_count());
442 }
443 assert(monitor_count() == incoming->monitor_count(), "monitors must match");
444
445 if (stack_size() == -1) {
446 set_stack_size(incoming->stack_size());
447 Cell limit = limit_cell();
448 #ifdef ASSERT
449 { for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
450 assert(type_at(c) == top_type(), "");
451 } }
452 #endif
453 // Make a simple copy of the incoming state.
454 for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
455 set_type_at(c, incoming->type_at(c));
456 }
457 return true; // it is always different the first time
458 }
459 #ifdef ASSERT
460 if (stack_size() != incoming->stack_size()) {
461 _outer->method()->print_codes();
462 tty->print_cr("!!!! Stack size conflict");
463 tty->print_cr("Current state:");
464 print_on(tty);
465 tty->print_cr("Incoming state:");
466 ((StateVector*)incoming)->print_on(tty);
467 }
468 #endif
469 assert(stack_size() == incoming->stack_size(), "sanity");
470
471 bool different = false;
472 Cell limit = limit_cell();
473 for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
474 ciType* t1 = type_at(c);
475 ciType* t2 = incoming->type_at(c);
476 if (!t1->equals(t2)) {
477 ciType* new_type = type_meet(t1, t2);
478 if (!t1->equals(new_type)) {
479 set_type_at(c, new_type);
480 different = true;
481 }
482 }
483 }
484 return different;
485 }
486
487 // ------------------------------------------------------------------
488 // ciTypeFlow::StateVector::meet_exception
489 //
490 // Meets this StateVector with another, destructively modifying this
491 // one. The incoming state is coming via an exception. Returns true
492 // if any modification takes place.
493 bool ciTypeFlow::StateVector::meet_exception(ciInstanceKlass* exc,
494 const ciTypeFlow::StateVector* incoming) {
495 if (monitor_count() == -1) {
496 set_monitor_count(incoming->monitor_count());
497 }
498 assert(monitor_count() == incoming->monitor_count(), "monitors must match");
499
500 if (stack_size() == -1) {
501 set_stack_size(1);
502 }
503
504 assert(stack_size() == 1, "must have one-element stack");
505
506 bool different = false;
507
508 // Meet locals from incoming array.
509 Cell limit = local(_outer->max_locals()-1);
510 for (Cell c = start_cell(); c <= limit; c = next_cell(c)) {
511 ciType* t1 = type_at(c);
512 ciType* t2 = incoming->type_at(c);
513 if (!t1->equals(t2)) {
514 ciType* new_type = type_meet(t1, t2);
515 if (!t1->equals(new_type)) {
516 set_type_at(c, new_type);
517 different = true;
518 }
519 }
520 }
521
522 // Handle stack separately. When an exception occurs, the
523 // only stack entry is the exception instance.
524 ciType* tos_type = type_at_tos();
525 if (!tos_type->equals(exc)) {
526 ciType* new_type = type_meet(tos_type, exc);
527 if (!tos_type->equals(new_type)) {
528 set_type_at_tos(new_type);
529 different = true;
530 }
531 }
532
533 return different;
534 }
535
536 // ------------------------------------------------------------------
537 // ciTypeFlow::StateVector::push_translate
538 void ciTypeFlow::StateVector::push_translate(ciType* type) {
539 BasicType basic_type = type->basic_type();
540 if (basic_type == T_BOOLEAN || basic_type == T_CHAR ||
541 basic_type == T_BYTE || basic_type == T_SHORT) {
542 push_int();
543 } else {
544 push(type);
545 if (type->is_two_word()) {
546 push(half_type(type));
547 }
548 }
549 }
550
551 // ------------------------------------------------------------------
552 // ciTypeFlow::StateVector::do_aload
553 void ciTypeFlow::StateVector::do_aload(ciBytecodeStream* str) {
554 pop_int();
555 ciArrayKlass* array_klass = pop_objOrValueArray();
556 if (array_klass == NULL) {
557 // Did aload on a null reference; push a null and ignore the exception.
558 // This instruction will never continue normally. All we have to do
559 // is report a value that will meet correctly with any downstream
560 // reference types on paths that will truly be executed. This null type
561 // meets with any reference type to yield that same reference type.
562 // (The compiler will generate an unconditional exception here.)
563 push(null_type());
564 return;
565 }
566 if (!array_klass->is_loaded()) {
567 // Only fails for some -Xcomp runs
568 trap(str, array_klass,
569 Deoptimization::make_trap_request
570 (Deoptimization::Reason_unloaded,
571 Deoptimization::Action_reinterpret));
572 return;
573 }
574 ciKlass* element_klass = array_klass->element_klass();
575 if (!element_klass->is_loaded() && element_klass->is_instance_klass()) {
576 Untested("unloaded array element class in ciTypeFlow");
577 trap(str, element_klass,
578 Deoptimization::make_trap_request
579 (Deoptimization::Reason_unloaded,
580 Deoptimization::Action_reinterpret));
581 } else {
582 push_object(element_klass);
583 }
584 }
585
586
587 // ------------------------------------------------------------------
588 // ciTypeFlow::StateVector::do_checkcast
589 void ciTypeFlow::StateVector::do_checkcast(ciBytecodeStream* str) {
590 bool will_link;
591 ciKlass* klass = str->get_klass(will_link);
592 if (!will_link) {
593 // VM's interpreter will not load 'klass' if object is NULL.
594 // Type flow after this block may still be needed in two situations:
595 // 1) C2 uses do_null_assert() and continues compilation for later blocks
596 // 2) C2 does an OSR compile in a later block (see bug 4778368).
597 pop_object();
598 do_null_assert(klass);
599 } else {
600 pop_object();
601 push_object(klass);
602 }
603 }
604
605 // ------------------------------------------------------------------
606 // ciTypeFlow::StateVector::do_getfield
607 void ciTypeFlow::StateVector::do_getfield(ciBytecodeStream* str) {
608 // could add assert here for type of object.
609 pop_object();
610 do_getstatic(str);
611 }
612
613 // ------------------------------------------------------------------
614 // ciTypeFlow::StateVector::do_getstatic
615 void ciTypeFlow::StateVector::do_getstatic(ciBytecodeStream* str) {
616 bool will_link;
617 ciField* field = str->get_field(will_link);
618 if (!will_link) {
619 trap(str, field->holder(), str->get_field_holder_index());
620 } else {
621 ciType* field_type = field->type();
622 if (!field_type->is_loaded()) {
623 // Normally, we need the field's type to be loaded if we are to
624 // do anything interesting with its value.
625 // We used to do this: trap(str, str->get_field_signature_index());
626 //
627 // There is one good reason not to trap here. Execution can
628 // get past this "getfield" or "getstatic" if the value of
629 // the field is null. As long as the value is null, the class
630 // does not need to be loaded! The compiler must assume that
631 // the value of the unloaded class reference is null; if the code
632 // ever sees a non-null value, loading has occurred.
633 //
634 // This actually happens often enough to be annoying. If the
635 // compiler throws an uncommon trap at this bytecode, you can
636 // get an endless loop of recompilations, when all the code
637 // needs to do is load a series of null values. Also, a trap
638 // here can make an OSR entry point unreachable, triggering the
639 // assert on non_osr_block in ciTypeFlow::get_start_state.
640 // (See bug 4379915.)
641 do_null_assert(field_type->as_klass());
642 } else {
643 push_translate(field_type);
644 }
645 }
646 }
647
648 // ------------------------------------------------------------------
649 // ciTypeFlow::StateVector::do_invoke
650 void ciTypeFlow::StateVector::do_invoke(ciBytecodeStream* str,
651 bool has_receiver) {
652 bool will_link;
653 ciSignature* declared_signature = NULL;
654 ciMethod* callee = str->get_method(will_link, &declared_signature);
655 assert(declared_signature != NULL, "cannot be null");
656 if (!will_link) {
657 // We weren't able to find the method.
658 if (str->cur_bc() == Bytecodes::_invokedynamic) {
659 trap(str, NULL,
660 Deoptimization::make_trap_request
661 (Deoptimization::Reason_uninitialized,
662 Deoptimization::Action_reinterpret));
663 } else {
664 ciKlass* unloaded_holder = callee->holder();
665 trap(str, unloaded_holder, str->get_method_holder_index());
666 }
667 } else {
668 // We are using the declared signature here because it might be
669 // different from the callee signature (Cf. invokedynamic and
670 // invokehandle).
671 ciSignatureStream sigstr(declared_signature);
672 const int arg_size = declared_signature->size();
673 const int stack_base = stack_size() - arg_size;
674 int i = 0;
675 for( ; !sigstr.at_return_type(); sigstr.next()) {
676 ciType* type = sigstr.type();
677 ciType* stack_type = type_at(stack(stack_base + i++));
678 // Do I want to check this type?
679 // assert(stack_type->is_subtype_of(type), "bad type for field value");
680 if (type->is_two_word()) {
681 ciType* stack_type2 = type_at(stack(stack_base + i++));
682 assert(stack_type2->equals(half_type(type)), "must be 2nd half");
683 }
684 }
685 assert(arg_size == i, "must match");
686 for (int j = 0; j < arg_size; j++) {
687 pop();
688 }
689 if (has_receiver) {
690 // Check this?
691 pop_object();
692 }
693 assert(!sigstr.is_done(), "must have return type");
694 ciType* return_type = sigstr.type();
695 if (!return_type->is_void()) {
696 if (!return_type->is_loaded()) {
697 // As in do_getstatic(), generally speaking, we need the return type to
698 // be loaded if we are to do anything interesting with its value.
699 // We used to do this: trap(str, str->get_method_signature_index());
700 //
701 // We do not trap here since execution can get past this invoke if
702 // the return value is null. As long as the value is null, the class
703 // does not need to be loaded! The compiler must assume that
704 // the value of the unloaded class reference is null; if the code
705 // ever sees a non-null value, loading has occurred.
706 //
707 // See do_getstatic() for similar explanation, as well as bug 4684993.
708 do_null_assert(return_type->as_klass());
709 } else {
710 push_translate(return_type);
711 }
712 }
713 }
714 }
715
716 // ------------------------------------------------------------------
717 // ciTypeFlow::StateVector::do_jsr
718 void ciTypeFlow::StateVector::do_jsr(ciBytecodeStream* str) {
719 push(ciReturnAddress::make(str->next_bci()));
720 }
721
722 // ------------------------------------------------------------------
723 // ciTypeFlow::StateVector::do_ldc
724 void ciTypeFlow::StateVector::do_ldc(ciBytecodeStream* str) {
725 ciConstant con = str->get_constant();
726 BasicType basic_type = con.basic_type();
727 if (basic_type == T_ILLEGAL) {
728 // OutOfMemoryError in the CI while loading constant
729 push_null();
730 outer()->record_failure("ldc did not link");
731 return;
732 }
733 if (basic_type == T_OBJECT || basic_type == T_ARRAY) {
734 ciObject* obj = con.as_object();
735 if (obj->is_null_object()) {
736 push_null();
737 } else {
738 assert(obj->is_instance() || obj->is_array(), "must be java_mirror of klass");
739 push_object(obj->klass());
740 }
741 } else {
742 push_translate(ciType::make(basic_type));
743 }
744 }
745
746 // ------------------------------------------------------------------
747 // ciTypeFlow::StateVector::do_multianewarray
748 void ciTypeFlow::StateVector::do_multianewarray(ciBytecodeStream* str) {
749 int dimensions = str->get_dimensions();
750 bool will_link;
751 ciArrayKlass* array_klass = str->get_klass(will_link)->as_array_klass();
752 if (!will_link) {
753 trap(str, array_klass, str->get_klass_index());
754 } else {
755 for (int i = 0; i < dimensions; i++) {
756 pop_int();
757 }
758 push_object(array_klass);
759 }
760 }
761
762 // ------------------------------------------------------------------
763 // ciTypeFlow::StateVector::do_new
764 void ciTypeFlow::StateVector::do_new(ciBytecodeStream* str) {
765 bool will_link;
766 ciKlass* klass = str->get_klass(will_link);
767 if (!will_link || str->is_unresolved_klass()) {
768 trap(str, klass, str->get_klass_index());
769 } else {
770 push_object(klass);
771 }
772 }
773
774 // ------------------------------------------------------------------
775 // ciTypeFlow::StateVector::do_vdefault
776 void ciTypeFlow::StateVector::do_vdefault(ciBytecodeStream* str) {
777 bool will_link;
778 ciKlass* klass = str->get_klass(will_link);
779 assert(klass->is_valuetype(), "should be value type");
780 if (!will_link || str->is_unresolved_value_type()) {
781 trap(str, klass, str->get_klass_index());
782 } else {
783 push_object(klass);
784 }
785 }
786
787 // ------------------------------------------------------------------
788 // ciTypeFlow::StateVector::do_vwithfield
789 void ciTypeFlow::StateVector::do_vwithfield(ciBytecodeStream* str) {
790 bool will_link;
791 ciField* field = str->get_field(will_link);
792 ciKlass* klass = field->holder();
793 assert(klass->is_valuetype(), "should be value type");
794 // TODO: add additional checks
795 ciType* type = pop_value();
796 ciType* field_type = field->type();
797 if (field_type->is_two_word()) {
798 ciType* type2 = pop_value();
799 assert(type2->is_two_word(), "must be 2nd half");
800 assert(type == half_type(type2), "must be 2nd half");
801 }
802 pop_object();
803 push_object(klass);
804 }
805
806 // ------------------------------------------------------------------
807 // ciTypeFlow::StateVector::do_newarray
808 void ciTypeFlow::StateVector::do_newarray(ciBytecodeStream* str) {
809 pop_int();
810 ciKlass* klass = ciTypeArrayKlass::make((BasicType)str->get_index());
811 push_object(klass);
812 }
813
814 // ------------------------------------------------------------------
815 // ciTypeFlow::StateVector::do_putfield
816 void ciTypeFlow::StateVector::do_putfield(ciBytecodeStream* str) {
817 do_putstatic(str);
818 if (_trap_bci != -1) return; // unloaded field holder, etc.
819 // could add assert here for type of object.
820 pop_object();
821 }
822
823 // ------------------------------------------------------------------
824 // ciTypeFlow::StateVector::do_putstatic
825 void ciTypeFlow::StateVector::do_putstatic(ciBytecodeStream* str) {
826 bool will_link;
827 ciField* field = str->get_field(will_link);
828 if (!will_link) {
829 trap(str, field->holder(), str->get_field_holder_index());
830 } else {
831 ciType* field_type = field->type();
832 ciType* type = pop_value();
833 // Do I want to check this type?
834 // assert(type->is_subtype_of(field_type), "bad type for field value");
835 if (field_type->is_two_word()) {
836 ciType* type2 = pop_value();
837 assert(type2->is_two_word(), "must be 2nd half");
838 assert(type == half_type(type2), "must be 2nd half");
839 }
840 }
841 }
842
843 // ------------------------------------------------------------------
844 // ciTypeFlow::StateVector::do_ret
845 void ciTypeFlow::StateVector::do_ret(ciBytecodeStream* str) {
846 Cell index = local(str->get_index());
847
848 ciType* address = type_at(index);
849 assert(address->is_return_address(), "bad return address");
850 set_type_at(index, bottom_type());
851 }
852
853 void ciTypeFlow::StateVector::do_vunbox(ciBytecodeStream* str) {
854 bool will_link;
855 ciKlass* klass = str->get_klass(will_link);
856 // TODO: Handle case when class is not loaded.
857 guarantee(will_link, "Class to which the value-capable class will unbox to must be loaded for JIT compilation");
858 assert(klass->is_instance_klass(), "must be an instance class");
859 pop_object();
860 push_object(klass->as_instance_klass());
861 }
862
863 void ciTypeFlow::StateVector::do_vbox(ciBytecodeStream* str) {
864 bool will_link;
865 ciKlass* klass = str->get_klass(will_link);
866 // TODO: Handle case when class is not loaded.
867 guarantee(will_link, "Class to which value type will box to must be loaded for JIT compilation");
868 assert(klass->is_instance_klass(), "must be an instance class");
869 pop_object();
870 push_object(klass->as_instance_klass());
871 }
872
873 // ------------------------------------------------------------------
874 // ciTypeFlow::StateVector::trap
875 //
876 // Stop interpretation of this path with a trap.
877 void ciTypeFlow::StateVector::trap(ciBytecodeStream* str, ciKlass* klass, int index) {
878 _trap_bci = str->cur_bci();
879 _trap_index = index;
880
881 // Log information about this trap:
882 CompileLog* log = outer()->env()->log();
883 if (log != NULL) {
884 int mid = log->identify(outer()->method());
885 int kid = (klass == NULL)? -1: log->identify(klass);
886 log->begin_elem("uncommon_trap method='%d' bci='%d'", mid, str->cur_bci());
887 char buf[100];
888 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
889 index));
890 if (kid >= 0)
891 log->print(" klass='%d'", kid);
892 log->end_elem();
893 }
894 }
895
896 // ------------------------------------------------------------------
897 // ciTypeFlow::StateVector::do_null_assert
898 // Corresponds to graphKit::do_null_assert.
899 void ciTypeFlow::StateVector::do_null_assert(ciKlass* unloaded_klass) {
900 if (unloaded_klass->is_loaded()) {
901 // We failed to link, but we can still compute with this class,
902 // since it is loaded somewhere. The compiler will uncommon_trap
903 // if the object is not null, but the typeflow pass can not assume
904 // that the object will be null, otherwise it may incorrectly tell
905 // the parser that an object is known to be null. 4761344, 4807707
906 push_object(unloaded_klass);
907 } else {
908 // The class is not loaded anywhere. It is safe to model the
909 // null in the typestates, because we can compile in a null check
910 // which will deoptimize us if someone manages to load the
911 // class later.
912 push_null();
913 }
914 }
915
916
917 // ------------------------------------------------------------------
918 // ciTypeFlow::StateVector::apply_one_bytecode
919 //
920 // Apply the effect of one bytecode to this StateVector
921 bool ciTypeFlow::StateVector::apply_one_bytecode(ciBytecodeStream* str) {
922 _trap_bci = -1;
923 _trap_index = 0;
924
925 if (CITraceTypeFlow) {
926 tty->print_cr(">> Interpreting bytecode %d:%s", str->cur_bci(),
927 Bytecodes::name(str->cur_bc()));
928 }
929
930 switch(str->cur_bc()) {
931 case Bytecodes::_vaload:
932 case Bytecodes::_aaload: do_aload(str); break;
933
934 case Bytecodes::_vastore:
935 case Bytecodes::_aastore:
936 {
937 pop_object();
938 pop_int();
939 pop_objOrValueArray();
940 break;
941 }
942 case Bytecodes::_aconst_null:
943 {
944 push_null();
945 break;
946 }
947 case Bytecodes::_vload:
948 case Bytecodes::_aload: load_local_object(str->get_index()); break;
949 case Bytecodes::_aload_0: load_local_object(0); break;
950 case Bytecodes::_aload_1: load_local_object(1); break;
951 case Bytecodes::_aload_2: load_local_object(2); break;
952 case Bytecodes::_aload_3: load_local_object(3); break;
953
954 case Bytecodes::_anewarray:
955 {
956 pop_int();
957 bool will_link;
958 ciKlass* element_klass = str->get_klass(will_link);
959 if (!will_link) {
960 trap(str, element_klass, str->get_klass_index());
961 } else {
962 push_object(ciArrayKlass::make(element_klass));
963 }
964 break;
965 }
966 case Bytecodes::_areturn:
967 case Bytecodes::_vreturn:
968 case Bytecodes::_ifnonnull:
969 case Bytecodes::_ifnull:
970 {
971 pop_object();
972 break;
973 }
974 case Bytecodes::_monitorenter:
975 {
976 pop_object();
977 set_monitor_count(monitor_count() + 1);
978 break;
979 }
980 case Bytecodes::_monitorexit:
981 {
982 pop_object();
983 assert(monitor_count() > 0, "must be a monitor to exit from");
984 set_monitor_count(monitor_count() - 1);
985 break;
986 }
987 case Bytecodes::_arraylength:
988 {
989 pop_array();
990 push_int();
991 break;
992 }
993 case Bytecodes::_vstore:
994 case Bytecodes::_astore: store_local_object(str->get_index()); break;
995 case Bytecodes::_astore_0: store_local_object(0); break;
996 case Bytecodes::_astore_1: store_local_object(1); break;
997 case Bytecodes::_astore_2: store_local_object(2); break;
998 case Bytecodes::_astore_3: store_local_object(3); break;
999
1000 case Bytecodes::_athrow:
1001 {
1002 NEEDS_CLEANUP;
1003 pop_object();
1004 break;
1005 }
1006 case Bytecodes::_baload:
1007 case Bytecodes::_caload:
1008 case Bytecodes::_iaload:
1009 case Bytecodes::_saload:
1010 {
1011 pop_int();
1012 ciTypeArrayKlass* array_klass = pop_typeArray();
1013 // Put assert here for right type?
1014 push_int();
1015 break;
1016 }
1017 case Bytecodes::_bastore:
1018 case Bytecodes::_castore:
1019 case Bytecodes::_iastore:
1020 case Bytecodes::_sastore:
1021 {
1022 pop_int();
1023 pop_int();
1024 pop_typeArray();
1025 // assert here?
1026 break;
1027 }
1028 case Bytecodes::_bipush:
1029 case Bytecodes::_iconst_m1:
1030 case Bytecodes::_iconst_0:
1031 case Bytecodes::_iconst_1:
1032 case Bytecodes::_iconst_2:
1033 case Bytecodes::_iconst_3:
1034 case Bytecodes::_iconst_4:
1035 case Bytecodes::_iconst_5:
1036 case Bytecodes::_sipush:
1037 {
1038 push_int();
1039 break;
1040 }
1041 case Bytecodes::_checkcast: do_checkcast(str); break;
1042
1043 case Bytecodes::_d2f:
1044 {
1045 pop_double();
1046 push_float();
1047 break;
1048 }
1049 case Bytecodes::_d2i:
1050 {
1051 pop_double();
1052 push_int();
1053 break;
1054 }
1055 case Bytecodes::_d2l:
1056 {
1057 pop_double();
1058 push_long();
1059 break;
1060 }
1061 case Bytecodes::_dadd:
1062 case Bytecodes::_ddiv:
1063 case Bytecodes::_dmul:
1064 case Bytecodes::_drem:
1065 case Bytecodes::_dsub:
1066 {
1067 pop_double();
1068 pop_double();
1069 push_double();
1070 break;
1071 }
1072 case Bytecodes::_daload:
1073 {
1074 pop_int();
1075 ciTypeArrayKlass* array_klass = pop_typeArray();
1076 // Put assert here for right type?
1077 push_double();
1078 break;
1079 }
1080 case Bytecodes::_dastore:
1081 {
1082 pop_double();
1083 pop_int();
1084 pop_typeArray();
1085 // assert here?
1086 break;
1087 }
1088 case Bytecodes::_dcmpg:
1089 case Bytecodes::_dcmpl:
1090 {
1091 pop_double();
1092 pop_double();
1093 push_int();
1094 break;
1095 }
1096 case Bytecodes::_dconst_0:
1097 case Bytecodes::_dconst_1:
1098 {
1099 push_double();
1100 break;
1101 }
1102 case Bytecodes::_dload: load_local_double(str->get_index()); break;
1103 case Bytecodes::_dload_0: load_local_double(0); break;
1104 case Bytecodes::_dload_1: load_local_double(1); break;
1105 case Bytecodes::_dload_2: load_local_double(2); break;
1106 case Bytecodes::_dload_3: load_local_double(3); break;
1107
1108 case Bytecodes::_dneg:
1109 {
1110 pop_double();
1111 push_double();
1112 break;
1113 }
1114 case Bytecodes::_dreturn:
1115 {
1116 pop_double();
1117 break;
1118 }
1119 case Bytecodes::_dstore: store_local_double(str->get_index()); break;
1120 case Bytecodes::_dstore_0: store_local_double(0); break;
1121 case Bytecodes::_dstore_1: store_local_double(1); break;
1122 case Bytecodes::_dstore_2: store_local_double(2); break;
1123 case Bytecodes::_dstore_3: store_local_double(3); break;
1124
1125 case Bytecodes::_dup:
1126 {
1127 push(type_at_tos());
1128 break;
1129 }
1130 case Bytecodes::_dup_x1:
1131 {
1132 ciType* value1 = pop_value();
1133 ciType* value2 = pop_value();
1134 push(value1);
1135 push(value2);
1136 push(value1);
1137 break;
1138 }
1139 case Bytecodes::_dup_x2:
1140 {
1141 ciType* value1 = pop_value();
1142 ciType* value2 = pop_value();
1143 ciType* value3 = pop_value();
1144 push(value1);
1145 push(value3);
1146 push(value2);
1147 push(value1);
1148 break;
1149 }
1150 case Bytecodes::_dup2:
1151 {
1152 ciType* value1 = pop_value();
1153 ciType* value2 = pop_value();
1154 push(value2);
1155 push(value1);
1156 push(value2);
1157 push(value1);
1158 break;
1159 }
1160 case Bytecodes::_dup2_x1:
1161 {
1162 ciType* value1 = pop_value();
1163 ciType* value2 = pop_value();
1164 ciType* value3 = pop_value();
1165 push(value2);
1166 push(value1);
1167 push(value3);
1168 push(value2);
1169 push(value1);
1170 break;
1171 }
1172 case Bytecodes::_dup2_x2:
1173 {
1174 ciType* value1 = pop_value();
1175 ciType* value2 = pop_value();
1176 ciType* value3 = pop_value();
1177 ciType* value4 = pop_value();
1178 push(value2);
1179 push(value1);
1180 push(value4);
1181 push(value3);
1182 push(value2);
1183 push(value1);
1184 break;
1185 }
1186 case Bytecodes::_f2d:
1187 {
1188 pop_float();
1189 push_double();
1190 break;
1191 }
1192 case Bytecodes::_f2i:
1193 {
1194 pop_float();
1195 push_int();
1196 break;
1197 }
1198 case Bytecodes::_f2l:
1199 {
1200 pop_float();
1201 push_long();
1202 break;
1203 }
1204 case Bytecodes::_fadd:
1205 case Bytecodes::_fdiv:
1206 case Bytecodes::_fmul:
1207 case Bytecodes::_frem:
1208 case Bytecodes::_fsub:
1209 {
1210 pop_float();
1211 pop_float();
1212 push_float();
1213 break;
1214 }
1215 case Bytecodes::_faload:
1216 {
1217 pop_int();
1218 ciTypeArrayKlass* array_klass = pop_typeArray();
1219 // Put assert here.
1220 push_float();
1221 break;
1222 }
1223 case Bytecodes::_fastore:
1224 {
1225 pop_float();
1226 pop_int();
1227 ciTypeArrayKlass* array_klass = pop_typeArray();
1228 // Put assert here.
1229 break;
1230 }
1231 case Bytecodes::_fcmpg:
1232 case Bytecodes::_fcmpl:
1233 {
1234 pop_float();
1235 pop_float();
1236 push_int();
1237 break;
1238 }
1239 case Bytecodes::_fconst_0:
1240 case Bytecodes::_fconst_1:
1241 case Bytecodes::_fconst_2:
1242 {
1243 push_float();
1244 break;
1245 }
1246 case Bytecodes::_fload: load_local_float(str->get_index()); break;
1247 case Bytecodes::_fload_0: load_local_float(0); break;
1248 case Bytecodes::_fload_1: load_local_float(1); break;
1249 case Bytecodes::_fload_2: load_local_float(2); break;
1250 case Bytecodes::_fload_3: load_local_float(3); break;
1251
1252 case Bytecodes::_fneg:
1253 {
1254 pop_float();
1255 push_float();
1256 break;
1257 }
1258 case Bytecodes::_freturn:
1259 {
1260 pop_float();
1261 break;
1262 }
1263 case Bytecodes::_fstore: store_local_float(str->get_index()); break;
1264 case Bytecodes::_fstore_0: store_local_float(0); break;
1265 case Bytecodes::_fstore_1: store_local_float(1); break;
1266 case Bytecodes::_fstore_2: store_local_float(2); break;
1267 case Bytecodes::_fstore_3: store_local_float(3); break;
1268
1269 case Bytecodes::_vgetfield:
1270 case Bytecodes::_getfield: do_getfield(str); break;
1271 case Bytecodes::_getstatic: do_getstatic(str); break;
1272
1273 case Bytecodes::_goto:
1274 case Bytecodes::_goto_w:
1275 case Bytecodes::_nop:
1276 case Bytecodes::_return:
1277 {
1278 // do nothing.
1279 break;
1280 }
1281 case Bytecodes::_i2b:
1282 case Bytecodes::_i2c:
1283 case Bytecodes::_i2s:
1284 case Bytecodes::_ineg:
1285 {
1286 pop_int();
1287 push_int();
1288 break;
1289 }
1290 case Bytecodes::_i2d:
1291 {
1292 pop_int();
1293 push_double();
1294 break;
1295 }
1296 case Bytecodes::_i2f:
1297 {
1298 pop_int();
1299 push_float();
1300 break;
1301 }
1302 case Bytecodes::_i2l:
1303 {
1304 pop_int();
1305 push_long();
1306 break;
1307 }
1308 case Bytecodes::_iadd:
1309 case Bytecodes::_iand:
1310 case Bytecodes::_idiv:
1311 case Bytecodes::_imul:
1312 case Bytecodes::_ior:
1313 case Bytecodes::_irem:
1314 case Bytecodes::_ishl:
1315 case Bytecodes::_ishr:
1316 case Bytecodes::_isub:
1317 case Bytecodes::_iushr:
1318 case Bytecodes::_ixor:
1319 {
1320 pop_int();
1321 pop_int();
1322 push_int();
1323 break;
1324 }
1325 case Bytecodes::_if_acmpeq:
1326 case Bytecodes::_if_acmpne:
1327 {
1328 pop_object();
1329 pop_object();
1330 break;
1331 }
1332 case Bytecodes::_if_icmpeq:
1333 case Bytecodes::_if_icmpge:
1334 case Bytecodes::_if_icmpgt:
1335 case Bytecodes::_if_icmple:
1336 case Bytecodes::_if_icmplt:
1337 case Bytecodes::_if_icmpne:
1338 {
1339 pop_int();
1340 pop_int();
1341 break;
1342 }
1343 case Bytecodes::_ifeq:
1344 case Bytecodes::_ifle:
1345 case Bytecodes::_iflt:
1346 case Bytecodes::_ifge:
1347 case Bytecodes::_ifgt:
1348 case Bytecodes::_ifne:
1349 case Bytecodes::_ireturn:
1350 case Bytecodes::_lookupswitch:
1351 case Bytecodes::_tableswitch:
1352 {
1353 pop_int();
1354 break;
1355 }
1356 case Bytecodes::_iinc:
1357 {
1358 int lnum = str->get_index();
1359 check_int(local(lnum));
1360 store_to_local(lnum);
1361 break;
1362 }
1363 case Bytecodes::_iload: load_local_int(str->get_index()); break;
1364 case Bytecodes::_iload_0: load_local_int(0); break;
1365 case Bytecodes::_iload_1: load_local_int(1); break;
1366 case Bytecodes::_iload_2: load_local_int(2); break;
1367 case Bytecodes::_iload_3: load_local_int(3); break;
1368
1369 case Bytecodes::_instanceof:
1370 {
1371 // Check for uncommon trap:
1372 do_checkcast(str);
1373 pop_object();
1374 push_int();
1375 break;
1376 }
1377 case Bytecodes::_invokeinterface: do_invoke(str, true); break;
1378 case Bytecodes::_invokespecial: do_invoke(str, true); break;
1379 case Bytecodes::_invokestatic: do_invoke(str, false); break;
1380 case Bytecodes::_invokevirtual: do_invoke(str, true); break;
1381 case Bytecodes::_invokedynamic: do_invoke(str, false); break;
1382
1383 case Bytecodes::_istore: store_local_int(str->get_index()); break;
1384 case Bytecodes::_istore_0: store_local_int(0); break;
1385 case Bytecodes::_istore_1: store_local_int(1); break;
1386 case Bytecodes::_istore_2: store_local_int(2); break;
1387 case Bytecodes::_istore_3: store_local_int(3); break;
1388
1389 case Bytecodes::_jsr:
1390 case Bytecodes::_jsr_w: do_jsr(str); break;
1391
1392 case Bytecodes::_l2d:
1393 {
1394 pop_long();
1395 push_double();
1396 break;
1397 }
1398 case Bytecodes::_l2f:
1399 {
1400 pop_long();
1401 push_float();
1402 break;
1403 }
1404 case Bytecodes::_l2i:
1405 {
1406 pop_long();
1407 push_int();
1408 break;
1409 }
1410 case Bytecodes::_ladd:
1411 case Bytecodes::_land:
1412 case Bytecodes::_ldiv:
1413 case Bytecodes::_lmul:
1414 case Bytecodes::_lor:
1415 case Bytecodes::_lrem:
1416 case Bytecodes::_lsub:
1417 case Bytecodes::_lxor:
1418 {
1419 pop_long();
1420 pop_long();
1421 push_long();
1422 break;
1423 }
1424 case Bytecodes::_laload:
1425 {
1426 pop_int();
1427 ciTypeArrayKlass* array_klass = pop_typeArray();
1428 // Put assert here for right type?
1429 push_long();
1430 break;
1431 }
1432 case Bytecodes::_lastore:
1433 {
1434 pop_long();
1435 pop_int();
1436 pop_typeArray();
1437 // assert here?
1438 break;
1439 }
1440 case Bytecodes::_lcmp:
1441 {
1442 pop_long();
1443 pop_long();
1444 push_int();
1445 break;
1446 }
1447 case Bytecodes::_lconst_0:
1448 case Bytecodes::_lconst_1:
1449 {
1450 push_long();
1451 break;
1452 }
1453 case Bytecodes::_ldc:
1454 case Bytecodes::_ldc_w:
1455 case Bytecodes::_ldc2_w:
1456 {
1457 do_ldc(str);
1458 break;
1459 }
1460
1461 case Bytecodes::_lload: load_local_long(str->get_index()); break;
1462 case Bytecodes::_lload_0: load_local_long(0); break;
1463 case Bytecodes::_lload_1: load_local_long(1); break;
1464 case Bytecodes::_lload_2: load_local_long(2); break;
1465 case Bytecodes::_lload_3: load_local_long(3); break;
1466
1467 case Bytecodes::_lneg:
1468 {
1469 pop_long();
1470 push_long();
1471 break;
1472 }
1473 case Bytecodes::_lreturn:
1474 {
1475 pop_long();
1476 break;
1477 }
1478 case Bytecodes::_lshl:
1479 case Bytecodes::_lshr:
1480 case Bytecodes::_lushr:
1481 {
1482 pop_int();
1483 pop_long();
1484 push_long();
1485 break;
1486 }
1487 case Bytecodes::_lstore: store_local_long(str->get_index()); break;
1488 case Bytecodes::_lstore_0: store_local_long(0); break;
1489 case Bytecodes::_lstore_1: store_local_long(1); break;
1490 case Bytecodes::_lstore_2: store_local_long(2); break;
1491 case Bytecodes::_lstore_3: store_local_long(3); break;
1492
1493 case Bytecodes::_multianewarray: do_multianewarray(str); break;
1494
1495 case Bytecodes::_new: do_new(str); break;
1496
1497 case Bytecodes::_vdefault: do_vdefault(str); break;
1498 case Bytecodes::_vwithfield: do_vwithfield(str); break;
1499
1500 case Bytecodes::_newarray: do_newarray(str); break;
1501
1502 case Bytecodes::_pop:
1503 {
1504 pop();
1505 break;
1506 }
1507 case Bytecodes::_pop2:
1508 {
1509 pop();
1510 pop();
1511 break;
1512 }
1513
1514 case Bytecodes::_putfield: do_putfield(str); break;
1515 case Bytecodes::_putstatic: do_putstatic(str); break;
1516
1517 case Bytecodes::_ret: do_ret(str); break;
1518
1519 case Bytecodes::_swap:
1520 {
1521 ciType* value1 = pop_value();
1522 ciType* value2 = pop_value();
1523 push(value1);
1524 push(value2);
1525 break;
1526 }
1527 case Bytecodes::_vunbox:
1528 {
1529 do_vunbox(str);
1530 break;
1531 }
1532 case Bytecodes::_vbox:
1533 {
1534 do_vbox(str);
1535 break;
1536 }
1537 case Bytecodes::_wide:
1538 default:
1539 {
1540 // The iterator should skip this.
1541 ShouldNotReachHere();
1542 break;
1543 }
1544 }
1545
1546 if (CITraceTypeFlow) {
1547 print_on(tty);
1548 }
1549
1550 return (_trap_bci != -1);
1551 }
1552
1553 #ifndef PRODUCT
1554 // ------------------------------------------------------------------
1555 // ciTypeFlow::StateVector::print_cell_on
1556 void ciTypeFlow::StateVector::print_cell_on(outputStream* st, Cell c) const {
1557 ciType* type = type_at(c);
1558 if (type == top_type()) {
1559 st->print("top");
1560 } else if (type == bottom_type()) {
1561 st->print("bottom");
1562 } else if (type == null_type()) {
1563 st->print("null");
1564 } else if (type == long2_type()) {
1565 st->print("long2");
1566 } else if (type == double2_type()) {
1567 st->print("double2");
1568 } else if (is_int(type)) {
1569 st->print("int");
1570 } else if (is_long(type)) {
1571 st->print("long");
1572 } else if (is_float(type)) {
1573 st->print("float");
1574 } else if (is_double(type)) {
1575 st->print("double");
1576 } else if (type->is_return_address()) {
1577 st->print("address(%d)", type->as_return_address()->bci());
1578 } else {
1579 if (type->is_klass()) {
1580 type->as_klass()->name()->print_symbol_on(st);
1581 } else {
1582 st->print("UNEXPECTED TYPE");
1583 type->print();
1584 }
1585 }
1586 }
1587
1588 // ------------------------------------------------------------------
1589 // ciTypeFlow::StateVector::print_on
1590 void ciTypeFlow::StateVector::print_on(outputStream* st) const {
1591 int num_locals = _outer->max_locals();
1592 int num_stack = stack_size();
1593 int num_monitors = monitor_count();
1594 st->print_cr(" State : locals %d, stack %d, monitors %d", num_locals, num_stack, num_monitors);
1595 if (num_stack >= 0) {
1596 int i;
1597 for (i = 0; i < num_locals; i++) {
1598 st->print(" local %2d : ", i);
1599 print_cell_on(st, local(i));
1600 st->cr();
1601 }
1602 for (i = 0; i < num_stack; i++) {
1603 st->print(" stack %2d : ", i);
1604 print_cell_on(st, stack(i));
1605 st->cr();
1606 }
1607 }
1608 }
1609 #endif
1610
1611
1612 // ------------------------------------------------------------------
1613 // ciTypeFlow::SuccIter::next
1614 //
1615 void ciTypeFlow::SuccIter::next() {
1616 int succ_ct = _pred->successors()->length();
1617 int next = _index + 1;
1618 if (next < succ_ct) {
1619 _index = next;
1620 _succ = _pred->successors()->at(next);
1621 return;
1622 }
1623 for (int i = next - succ_ct; i < _pred->exceptions()->length(); i++) {
1624 // Do not compile any code for unloaded exception types.
1625 // Following compiler passes are responsible for doing this also.
1626 ciInstanceKlass* exception_klass = _pred->exc_klasses()->at(i);
1627 if (exception_klass->is_loaded()) {
1628 _index = next;
1629 _succ = _pred->exceptions()->at(i);
1630 return;
1631 }
1632 next++;
1633 }
1634 _index = -1;
1635 _succ = NULL;
1636 }
1637
1638 // ------------------------------------------------------------------
1639 // ciTypeFlow::SuccIter::set_succ
1640 //
1641 void ciTypeFlow::SuccIter::set_succ(Block* succ) {
1642 int succ_ct = _pred->successors()->length();
1643 if (_index < succ_ct) {
1644 _pred->successors()->at_put(_index, succ);
1645 } else {
1646 int idx = _index - succ_ct;
1647 _pred->exceptions()->at_put(idx, succ);
1648 }
1649 }
1650
1651 // ciTypeFlow::Block
1652 //
1653 // A basic block.
1654
1655 // ------------------------------------------------------------------
1656 // ciTypeFlow::Block::Block
1657 ciTypeFlow::Block::Block(ciTypeFlow* outer,
1658 ciBlock *ciblk,
1659 ciTypeFlow::JsrSet* jsrs) {
1660 _ciblock = ciblk;
1661 _exceptions = NULL;
1662 _exc_klasses = NULL;
1663 _successors = NULL;
1664 _predecessors = new (outer->arena()) GrowableArray<Block*>(outer->arena(), 1, 0, NULL);
1665 _state = new (outer->arena()) StateVector(outer);
1666 JsrSet* new_jsrs =
1667 new (outer->arena()) JsrSet(outer->arena(), jsrs->size());
1668 jsrs->copy_into(new_jsrs);
1669 _jsrs = new_jsrs;
1670 _next = NULL;
1671 _on_work_list = false;
1672 _backedge_copy = false;
1673 _has_monitorenter = false;
1674 _trap_bci = -1;
1675 _trap_index = 0;
1676 df_init();
1677
1678 if (CITraceTypeFlow) {
1679 tty->print_cr(">> Created new block");
1680 print_on(tty);
1681 }
1682
1683 assert(this->outer() == outer, "outer link set up");
1684 assert(!outer->have_block_count(), "must not have mapped blocks yet");
1685 }
1686
1687 // ------------------------------------------------------------------
1688 // ciTypeFlow::Block::df_init
1689 void ciTypeFlow::Block::df_init() {
1690 _pre_order = -1; assert(!has_pre_order(), "");
1691 _post_order = -1; assert(!has_post_order(), "");
1692 _loop = NULL;
1693 _irreducible_entry = false;
1694 _rpo_next = NULL;
1695 }
1696
1697 // ------------------------------------------------------------------
1698 // ciTypeFlow::Block::successors
1699 //
1700 // Get the successors for this Block.
1701 GrowableArray<ciTypeFlow::Block*>*
1702 ciTypeFlow::Block::successors(ciBytecodeStream* str,
1703 ciTypeFlow::StateVector* state,
1704 ciTypeFlow::JsrSet* jsrs) {
1705 if (_successors == NULL) {
1706 if (CITraceTypeFlow) {
1707 tty->print(">> Computing successors for block ");
1708 print_value_on(tty);
1709 tty->cr();
1710 }
1711
1712 ciTypeFlow* analyzer = outer();
1713 Arena* arena = analyzer->arena();
1714 Block* block = NULL;
1715 bool has_successor = !has_trap() &&
1716 (control() != ciBlock::fall_through_bci || limit() < analyzer->code_size());
1717 if (!has_successor) {
1718 _successors =
1719 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1720 // No successors
1721 } else if (control() == ciBlock::fall_through_bci) {
1722 assert(str->cur_bci() == limit(), "bad block end");
1723 // This block simply falls through to the next.
1724 _successors =
1725 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1726
1727 Block* block = analyzer->block_at(limit(), _jsrs);
1728 assert(_successors->length() == FALL_THROUGH, "");
1729 _successors->append(block);
1730 } else {
1731 int current_bci = str->cur_bci();
1732 int next_bci = str->next_bci();
1733 int branch_bci = -1;
1734 Block* target = NULL;
1735 assert(str->next_bci() == limit(), "bad block end");
1736 // This block is not a simple fall-though. Interpret
1737 // the current bytecode to find our successors.
1738 switch (str->cur_bc()) {
1739 case Bytecodes::_ifeq: case Bytecodes::_ifne:
1740 case Bytecodes::_iflt: case Bytecodes::_ifge:
1741 case Bytecodes::_ifgt: case Bytecodes::_ifle:
1742 case Bytecodes::_if_icmpeq: case Bytecodes::_if_icmpne:
1743 case Bytecodes::_if_icmplt: case Bytecodes::_if_icmpge:
1744 case Bytecodes::_if_icmpgt: case Bytecodes::_if_icmple:
1745 case Bytecodes::_if_acmpeq: case Bytecodes::_if_acmpne:
1746 case Bytecodes::_ifnull: case Bytecodes::_ifnonnull:
1747 // Our successors are the branch target and the next bci.
1748 branch_bci = str->get_dest();
1749 _successors =
1750 new (arena) GrowableArray<Block*>(arena, 2, 0, NULL);
1751 assert(_successors->length() == IF_NOT_TAKEN, "");
1752 _successors->append(analyzer->block_at(next_bci, jsrs));
1753 assert(_successors->length() == IF_TAKEN, "");
1754 _successors->append(analyzer->block_at(branch_bci, jsrs));
1755 break;
1756
1757 case Bytecodes::_goto:
1758 branch_bci = str->get_dest();
1759 _successors =
1760 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1761 assert(_successors->length() == GOTO_TARGET, "");
1762 _successors->append(analyzer->block_at(branch_bci, jsrs));
1763 break;
1764
1765 case Bytecodes::_jsr:
1766 branch_bci = str->get_dest();
1767 _successors =
1768 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1769 assert(_successors->length() == GOTO_TARGET, "");
1770 _successors->append(analyzer->block_at(branch_bci, jsrs));
1771 break;
1772
1773 case Bytecodes::_goto_w:
1774 case Bytecodes::_jsr_w:
1775 _successors =
1776 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1777 assert(_successors->length() == GOTO_TARGET, "");
1778 _successors->append(analyzer->block_at(str->get_far_dest(), jsrs));
1779 break;
1780
1781 case Bytecodes::_tableswitch: {
1782 Bytecode_tableswitch tableswitch(str);
1783
1784 int len = tableswitch.length();
1785 _successors =
1786 new (arena) GrowableArray<Block*>(arena, len+1, 0, NULL);
1787 int bci = current_bci + tableswitch.default_offset();
1788 Block* block = analyzer->block_at(bci, jsrs);
1789 assert(_successors->length() == SWITCH_DEFAULT, "");
1790 _successors->append(block);
1791 while (--len >= 0) {
1792 int bci = current_bci + tableswitch.dest_offset_at(len);
1793 block = analyzer->block_at(bci, jsrs);
1794 assert(_successors->length() >= SWITCH_CASES, "");
1795 _successors->append_if_missing(block);
1796 }
1797 break;
1798 }
1799
1800 case Bytecodes::_lookupswitch: {
1801 Bytecode_lookupswitch lookupswitch(str);
1802
1803 int npairs = lookupswitch.number_of_pairs();
1804 _successors =
1805 new (arena) GrowableArray<Block*>(arena, npairs+1, 0, NULL);
1806 int bci = current_bci + lookupswitch.default_offset();
1807 Block* block = analyzer->block_at(bci, jsrs);
1808 assert(_successors->length() == SWITCH_DEFAULT, "");
1809 _successors->append(block);
1810 while(--npairs >= 0) {
1811 LookupswitchPair pair = lookupswitch.pair_at(npairs);
1812 int bci = current_bci + pair.offset();
1813 Block* block = analyzer->block_at(bci, jsrs);
1814 assert(_successors->length() >= SWITCH_CASES, "");
1815 _successors->append_if_missing(block);
1816 }
1817 break;
1818 }
1819
1820 case Bytecodes::_athrow:
1821 case Bytecodes::_ireturn:
1822 case Bytecodes::_lreturn:
1823 case Bytecodes::_freturn:
1824 case Bytecodes::_dreturn:
1825 case Bytecodes::_areturn:
1826 case Bytecodes::_vreturn:
1827 case Bytecodes::_return:
1828 _successors =
1829 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1830 // No successors
1831 break;
1832
1833 case Bytecodes::_ret: {
1834 _successors =
1835 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1836
1837 Cell local = state->local(str->get_index());
1838 ciType* return_address = state->type_at(local);
1839 assert(return_address->is_return_address(), "verify: wrong type");
1840 int bci = return_address->as_return_address()->bci();
1841 assert(_successors->length() == GOTO_TARGET, "");
1842 _successors->append(analyzer->block_at(bci, jsrs));
1843 break;
1844 }
1845
1846 case Bytecodes::_wide:
1847 default:
1848 ShouldNotReachHere();
1849 break;
1850 }
1851 }
1852
1853 // Set predecessor information
1854 for (int i = 0; i < _successors->length(); i++) {
1855 Block* block = _successors->at(i);
1856 block->predecessors()->append(this);
1857 }
1858 }
1859 return _successors;
1860 }
1861
1862 // ------------------------------------------------------------------
1863 // ciTypeFlow::Block:compute_exceptions
1864 //
1865 // Compute the exceptional successors and types for this Block.
1866 void ciTypeFlow::Block::compute_exceptions() {
1867 assert(_exceptions == NULL && _exc_klasses == NULL, "repeat");
1868
1869 if (CITraceTypeFlow) {
1870 tty->print(">> Computing exceptions for block ");
1871 print_value_on(tty);
1872 tty->cr();
1873 }
1874
1875 ciTypeFlow* analyzer = outer();
1876 Arena* arena = analyzer->arena();
1877
1878 // Any bci in the block will do.
1879 ciExceptionHandlerStream str(analyzer->method(), start());
1880
1881 // Allocate our growable arrays.
1882 int exc_count = str.count();
1883 _exceptions = new (arena) GrowableArray<Block*>(arena, exc_count, 0, NULL);
1884 _exc_klasses = new (arena) GrowableArray<ciInstanceKlass*>(arena, exc_count,
1885 0, NULL);
1886
1887 for ( ; !str.is_done(); str.next()) {
1888 ciExceptionHandler* handler = str.handler();
1889 int bci = handler->handler_bci();
1890 ciInstanceKlass* klass = NULL;
1891 if (bci == -1) {
1892 // There is no catch all. It is possible to exit the method.
1893 break;
1894 }
1895 if (handler->is_catch_all()) {
1896 klass = analyzer->env()->Throwable_klass();
1897 } else {
1898 klass = handler->catch_klass();
1899 }
1900 Block* block = analyzer->block_at(bci, _jsrs);
1901 _exceptions->append(block);
1902 block->predecessors()->append(this);
1903 _exc_klasses->append(klass);
1904 }
1905 }
1906
1907 // ------------------------------------------------------------------
1908 // ciTypeFlow::Block::set_backedge_copy
1909 // Use this only to make a pre-existing public block into a backedge copy.
1910 void ciTypeFlow::Block::set_backedge_copy(bool z) {
1911 assert(z || (z == is_backedge_copy()), "cannot make a backedge copy public");
1912 _backedge_copy = z;
1913 }
1914
1915 // ------------------------------------------------------------------
1916 // ciTypeFlow::Block::is_clonable_exit
1917 //
1918 // At most 2 normal successors, one of which continues looping,
1919 // and all exceptional successors must exit.
1920 bool ciTypeFlow::Block::is_clonable_exit(ciTypeFlow::Loop* lp) {
1921 int normal_cnt = 0;
1922 int in_loop_cnt = 0;
1923 for (SuccIter iter(this); !iter.done(); iter.next()) {
1924 Block* succ = iter.succ();
1925 if (iter.is_normal_ctrl()) {
1926 if (++normal_cnt > 2) return false;
1927 if (lp->contains(succ->loop())) {
1928 if (++in_loop_cnt > 1) return false;
1929 }
1930 } else {
1931 if (lp->contains(succ->loop())) return false;
1932 }
1933 }
1934 return in_loop_cnt == 1;
1935 }
1936
1937 // ------------------------------------------------------------------
1938 // ciTypeFlow::Block::looping_succ
1939 //
1940 ciTypeFlow::Block* ciTypeFlow::Block::looping_succ(ciTypeFlow::Loop* lp) {
1941 assert(successors()->length() <= 2, "at most 2 normal successors");
1942 for (SuccIter iter(this); !iter.done(); iter.next()) {
1943 Block* succ = iter.succ();
1944 if (lp->contains(succ->loop())) {
1945 return succ;
1946 }
1947 }
1948 return NULL;
1949 }
1950
1951 #ifndef PRODUCT
1952 // ------------------------------------------------------------------
1953 // ciTypeFlow::Block::print_value_on
1954 void ciTypeFlow::Block::print_value_on(outputStream* st) const {
1955 if (has_pre_order()) st->print("#%-2d ", pre_order());
1956 if (has_rpo()) st->print("rpo#%-2d ", rpo());
1957 st->print("[%d - %d)", start(), limit());
1958 if (is_loop_head()) st->print(" lphd");
1959 if (is_irreducible_entry()) st->print(" irred");
1960 if (_jsrs->size() > 0) { st->print("/"); _jsrs->print_on(st); }
1961 if (is_backedge_copy()) st->print("/backedge_copy");
1962 }
1963
1964 // ------------------------------------------------------------------
1965 // ciTypeFlow::Block::print_on
1966 void ciTypeFlow::Block::print_on(outputStream* st) const {
1967 if ((Verbose || WizardMode) && (limit() >= 0)) {
1968 // Don't print 'dummy' blocks (i.e. blocks with limit() '-1')
1969 outer()->method()->print_codes_on(start(), limit(), st);
1970 }
1971 st->print_cr(" ==================================================== ");
1972 st->print (" ");
1973 print_value_on(st);
1974 st->print(" Stored locals: "); def_locals()->print_on(st, outer()->method()->max_locals()); tty->cr();
1975 if (loop() && loop()->parent() != NULL) {
1976 st->print(" loops:");
1977 Loop* lp = loop();
1978 do {
1979 st->print(" %d<-%d", lp->head()->pre_order(),lp->tail()->pre_order());
1980 if (lp->is_irreducible()) st->print("(ir)");
1981 lp = lp->parent();
1982 } while (lp->parent() != NULL);
1983 }
1984 st->cr();
1985 _state->print_on(st);
1986 if (_successors == NULL) {
1987 st->print_cr(" No successor information");
1988 } else {
1989 int num_successors = _successors->length();
1990 st->print_cr(" Successors : %d", num_successors);
1991 for (int i = 0; i < num_successors; i++) {
1992 Block* successor = _successors->at(i);
1993 st->print(" ");
1994 successor->print_value_on(st);
1995 st->cr();
1996 }
1997 }
1998 if (_predecessors == NULL) {
1999 st->print_cr(" No predecessor information");
2000 } else {
2001 int num_predecessors = _predecessors->length();
2002 st->print_cr(" Predecessors : %d", num_predecessors);
2003 for (int i = 0; i < num_predecessors; i++) {
2004 Block* predecessor = _predecessors->at(i);
2005 st->print(" ");
2006 predecessor->print_value_on(st);
2007 st->cr();
2008 }
2009 }
2010 if (_exceptions == NULL) {
2011 st->print_cr(" No exception information");
2012 } else {
2013 int num_exceptions = _exceptions->length();
2014 st->print_cr(" Exceptions : %d", num_exceptions);
2015 for (int i = 0; i < num_exceptions; i++) {
2016 Block* exc_succ = _exceptions->at(i);
2017 ciInstanceKlass* exc_klass = _exc_klasses->at(i);
2018 st->print(" ");
2019 exc_succ->print_value_on(st);
2020 st->print(" -- ");
2021 exc_klass->name()->print_symbol_on(st);
2022 st->cr();
2023 }
2024 }
2025 if (has_trap()) {
2026 st->print_cr(" Traps on %d with trap index %d", trap_bci(), trap_index());
2027 }
2028 st->print_cr(" ==================================================== ");
2029 }
2030 #endif
2031
2032 #ifndef PRODUCT
2033 // ------------------------------------------------------------------
2034 // ciTypeFlow::LocalSet::print_on
2035 void ciTypeFlow::LocalSet::print_on(outputStream* st, int limit) const {
2036 st->print("{");
2037 for (int i = 0; i < max; i++) {
2038 if (test(i)) st->print(" %d", i);
2039 }
2040 if (limit > max) {
2041 st->print(" %d..%d ", max, limit);
2042 }
2043 st->print(" }");
2044 }
2045 #endif
2046
2047 // ciTypeFlow
2048 //
2049 // This is a pass over the bytecodes which computes the following:
2050 // basic block structure
2051 // interpreter type-states (a la the verifier)
2052
2053 // ------------------------------------------------------------------
2054 // ciTypeFlow::ciTypeFlow
2055 ciTypeFlow::ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci) {
2056 _env = env;
2057 _method = method;
2058 _methodBlocks = method->get_method_blocks();
2059 _max_locals = method->max_locals();
2060 _max_stack = method->max_stack();
2061 _code_size = method->code_size();
2062 _has_irreducible_entry = false;
2063 _osr_bci = osr_bci;
2064 _failure_reason = NULL;
2065 assert(0 <= start_bci() && start_bci() < code_size() , "correct osr_bci argument: 0 <= %d < %d", start_bci(), code_size());
2066 _work_list = NULL;
2067
2068 _ciblock_count = _methodBlocks->num_blocks();
2069 _idx_to_blocklist = NEW_ARENA_ARRAY(arena(), GrowableArray<Block*>*, _ciblock_count);
2070 for (int i = 0; i < _ciblock_count; i++) {
2071 _idx_to_blocklist[i] = NULL;
2072 }
2073 _block_map = NULL; // until all blocks are seen
2074 _jsr_count = 0;
2075 _jsr_records = NULL;
2076 }
2077
2078 // ------------------------------------------------------------------
2079 // ciTypeFlow::work_list_next
2080 //
2081 // Get the next basic block from our work list.
2082 ciTypeFlow::Block* ciTypeFlow::work_list_next() {
2083 assert(!work_list_empty(), "work list must not be empty");
2084 Block* next_block = _work_list;
2085 _work_list = next_block->next();
2086 next_block->set_next(NULL);
2087 next_block->set_on_work_list(false);
2088 return next_block;
2089 }
2090
2091 // ------------------------------------------------------------------
2092 // ciTypeFlow::add_to_work_list
2093 //
2094 // Add a basic block to our work list.
2095 // List is sorted by decreasing postorder sort (same as increasing RPO)
2096 void ciTypeFlow::add_to_work_list(ciTypeFlow::Block* block) {
2097 assert(!block->is_on_work_list(), "must not already be on work list");
2098
2099 if (CITraceTypeFlow) {
2100 tty->print(">> Adding block ");
2101 block->print_value_on(tty);
2102 tty->print_cr(" to the work list : ");
2103 }
2104
2105 block->set_on_work_list(true);
2106
2107 // decreasing post order sort
2108
2109 Block* prev = NULL;
2110 Block* current = _work_list;
2111 int po = block->post_order();
2112 while (current != NULL) {
2113 if (!current->has_post_order() || po > current->post_order())
2114 break;
2115 prev = current;
2116 current = current->next();
2117 }
2118 if (prev == NULL) {
2119 block->set_next(_work_list);
2120 _work_list = block;
2121 } else {
2122 block->set_next(current);
2123 prev->set_next(block);
2124 }
2125
2126 if (CITraceTypeFlow) {
2127 tty->cr();
2128 }
2129 }
2130
2131 // ------------------------------------------------------------------
2132 // ciTypeFlow::block_at
2133 //
2134 // Return the block beginning at bci which has a JsrSet compatible
2135 // with jsrs.
2136 ciTypeFlow::Block* ciTypeFlow::block_at(int bci, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
2137 // First find the right ciBlock.
2138 if (CITraceTypeFlow) {
2139 tty->print(">> Requesting block for %d/", bci);
2140 jsrs->print_on(tty);
2141 tty->cr();
2142 }
2143
2144 ciBlock* ciblk = _methodBlocks->block_containing(bci);
2145 assert(ciblk->start_bci() == bci, "bad ciBlock boundaries");
2146 Block* block = get_block_for(ciblk->index(), jsrs, option);
2147
2148 assert(block == NULL? (option == no_create): block->is_backedge_copy() == (option == create_backedge_copy), "create option consistent with result");
2149
2150 if (CITraceTypeFlow) {
2151 if (block != NULL) {
2152 tty->print(">> Found block ");
2153 block->print_value_on(tty);
2154 tty->cr();
2155 } else {
2156 tty->print_cr(">> No such block.");
2157 }
2158 }
2159
2160 return block;
2161 }
2162
2163 // ------------------------------------------------------------------
2164 // ciTypeFlow::make_jsr_record
2165 //
2166 // Make a JsrRecord for a given (entry, return) pair, if such a record
2167 // does not already exist.
2168 ciTypeFlow::JsrRecord* ciTypeFlow::make_jsr_record(int entry_address,
2169 int return_address) {
2170 if (_jsr_records == NULL) {
2171 _jsr_records = new (arena()) GrowableArray<JsrRecord*>(arena(),
2172 _jsr_count,
2173 0,
2174 NULL);
2175 }
2176 JsrRecord* record = NULL;
2177 int len = _jsr_records->length();
2178 for (int i = 0; i < len; i++) {
2179 JsrRecord* record = _jsr_records->at(i);
2180 if (record->entry_address() == entry_address &&
2181 record->return_address() == return_address) {
2182 return record;
2183 }
2184 }
2185
2186 record = new (arena()) JsrRecord(entry_address, return_address);
2187 _jsr_records->append(record);
2188 return record;
2189 }
2190
2191 // ------------------------------------------------------------------
2192 // ciTypeFlow::flow_exceptions
2193 //
2194 // Merge the current state into all exceptional successors at the
2195 // current point in the code.
2196 void ciTypeFlow::flow_exceptions(GrowableArray<ciTypeFlow::Block*>* exceptions,
2197 GrowableArray<ciInstanceKlass*>* exc_klasses,
2198 ciTypeFlow::StateVector* state) {
2199 int len = exceptions->length();
2200 assert(exc_klasses->length() == len, "must have same length");
2201 for (int i = 0; i < len; i++) {
2202 Block* block = exceptions->at(i);
2203 ciInstanceKlass* exception_klass = exc_klasses->at(i);
2204
2205 if (!exception_klass->is_loaded()) {
2206 // Do not compile any code for unloaded exception types.
2207 // Following compiler passes are responsible for doing this also.
2208 continue;
2209 }
2210
2211 if (block->meet_exception(exception_klass, state)) {
2212 // Block was modified and has PO. Add it to the work list.
2213 if (block->has_post_order() &&
2214 !block->is_on_work_list()) {
2215 add_to_work_list(block);
2216 }
2217 }
2218 }
2219 }
2220
2221 // ------------------------------------------------------------------
2222 // ciTypeFlow::flow_successors
2223 //
2224 // Merge the current state into all successors at the current point
2225 // in the code.
2226 void ciTypeFlow::flow_successors(GrowableArray<ciTypeFlow::Block*>* successors,
2227 ciTypeFlow::StateVector* state) {
2228 int len = successors->length();
2229 for (int i = 0; i < len; i++) {
2230 Block* block = successors->at(i);
2231 if (block->meet(state)) {
2232 // Block was modified and has PO. Add it to the work list.
2233 if (block->has_post_order() &&
2234 !block->is_on_work_list()) {
2235 add_to_work_list(block);
2236 }
2237 }
2238 }
2239 }
2240
2241 // ------------------------------------------------------------------
2242 // ciTypeFlow::can_trap
2243 //
2244 // Tells if a given instruction is able to generate an exception edge.
2245 bool ciTypeFlow::can_trap(ciBytecodeStream& str) {
2246 // Cf. GenerateOopMap::do_exception_edge.
2247 if (!Bytecodes::can_trap(str.cur_bc())) return false;
2248
2249 switch (str.cur_bc()) {
2250 // %%% FIXME: ldc of Class can generate an exception
2251 case Bytecodes::_ldc:
2252 case Bytecodes::_ldc_w:
2253 case Bytecodes::_ldc2_w:
2254 case Bytecodes::_aload_0:
2255 // These bytecodes can trap for rewriting. We need to assume that
2256 // they do not throw exceptions to make the monitor analysis work.
2257 return false;
2258
2259 case Bytecodes::_ireturn:
2260 case Bytecodes::_lreturn:
2261 case Bytecodes::_freturn:
2262 case Bytecodes::_dreturn:
2263 case Bytecodes::_areturn:
2264 case Bytecodes::_vreturn:
2265 case Bytecodes::_return:
2266 // We can assume the monitor stack is empty in this analysis.
2267 return false;
2268
2269 case Bytecodes::_monitorexit:
2270 // We can assume monitors are matched in this analysis.
2271 return false;
2272 }
2273
2274 return true;
2275 }
2276
2277 // ------------------------------------------------------------------
2278 // ciTypeFlow::clone_loop_heads
2279 //
2280 // Clone the loop heads
2281 bool ciTypeFlow::clone_loop_heads(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) {
2282 bool rslt = false;
2283 for (PreorderLoops iter(loop_tree_root()); !iter.done(); iter.next()) {
2284 lp = iter.current();
2285 Block* head = lp->head();
2286 if (lp == loop_tree_root() ||
2287 lp->is_irreducible() ||
2288 !head->is_clonable_exit(lp))
2289 continue;
2290
2291 // Avoid BoxLock merge.
2292 if (EliminateNestedLocks && head->has_monitorenter())
2293 continue;
2294
2295 // check not already cloned
2296 if (head->backedge_copy_count() != 0)
2297 continue;
2298
2299 // Don't clone head of OSR loop to get correct types in start block.
2300 if (is_osr_flow() && head->start() == start_bci())
2301 continue;
2302
2303 // check _no_ shared head below us
2304 Loop* ch;
2305 for (ch = lp->child(); ch != NULL && ch->head() != head; ch = ch->sibling());
2306 if (ch != NULL)
2307 continue;
2308
2309 // Clone head
2310 Block* new_head = head->looping_succ(lp);
2311 Block* clone = clone_loop_head(lp, temp_vector, temp_set);
2312 // Update lp's info
2313 clone->set_loop(lp);
2314 lp->set_head(new_head);
2315 lp->set_tail(clone);
2316 // And move original head into outer loop
2317 head->set_loop(lp->parent());
2318
2319 rslt = true;
2320 }
2321 return rslt;
2322 }
2323
2324 // ------------------------------------------------------------------
2325 // ciTypeFlow::clone_loop_head
2326 //
2327 // Clone lp's head and replace tail's successors with clone.
2328 //
2329 // |
2330 // v
2331 // head <-> body
2332 // |
2333 // v
2334 // exit
2335 //
2336 // new_head
2337 //
2338 // |
2339 // v
2340 // head ----------\
2341 // | |
2342 // | v
2343 // | clone <-> body
2344 // | |
2345 // | /--/
2346 // | |
2347 // v v
2348 // exit
2349 //
2350 ciTypeFlow::Block* ciTypeFlow::clone_loop_head(Loop* lp, StateVector* temp_vector, JsrSet* temp_set) {
2351 Block* head = lp->head();
2352 Block* tail = lp->tail();
2353 if (CITraceTypeFlow) {
2354 tty->print(">> Requesting clone of loop head "); head->print_value_on(tty);
2355 tty->print(" for predecessor "); tail->print_value_on(tty);
2356 tty->cr();
2357 }
2358 Block* clone = block_at(head->start(), head->jsrs(), create_backedge_copy);
2359 assert(clone->backedge_copy_count() == 1, "one backedge copy for all back edges");
2360
2361 assert(!clone->has_pre_order(), "just created");
2362 clone->set_next_pre_order();
2363
2364 // Insert clone after (orig) tail in reverse post order
2365 clone->set_rpo_next(tail->rpo_next());
2366 tail->set_rpo_next(clone);
2367
2368 // tail->head becomes tail->clone
2369 for (SuccIter iter(tail); !iter.done(); iter.next()) {
2370 if (iter.succ() == head) {
2371 iter.set_succ(clone);
2372 // Update predecessor information
2373 head->predecessors()->remove(tail);
2374 clone->predecessors()->append(tail);
2375 }
2376 }
2377 flow_block(tail, temp_vector, temp_set);
2378 if (head == tail) {
2379 // For self-loops, clone->head becomes clone->clone
2380 flow_block(clone, temp_vector, temp_set);
2381 for (SuccIter iter(clone); !iter.done(); iter.next()) {
2382 if (iter.succ() == head) {
2383 iter.set_succ(clone);
2384 // Update predecessor information
2385 head->predecessors()->remove(clone);
2386 clone->predecessors()->append(clone);
2387 break;
2388 }
2389 }
2390 }
2391 flow_block(clone, temp_vector, temp_set);
2392
2393 return clone;
2394 }
2395
2396 // ------------------------------------------------------------------
2397 // ciTypeFlow::flow_block
2398 //
2399 // Interpret the effects of the bytecodes on the incoming state
2400 // vector of a basic block. Push the changed state to succeeding
2401 // basic blocks.
2402 void ciTypeFlow::flow_block(ciTypeFlow::Block* block,
2403 ciTypeFlow::StateVector* state,
2404 ciTypeFlow::JsrSet* jsrs) {
2405 if (CITraceTypeFlow) {
2406 tty->print("\n>> ANALYZING BLOCK : ");
2407 tty->cr();
2408 block->print_on(tty);
2409 }
2410 assert(block->has_pre_order(), "pre-order is assigned before 1st flow");
2411
2412 int start = block->start();
2413 int limit = block->limit();
2414 int control = block->control();
2415 if (control != ciBlock::fall_through_bci) {
2416 limit = control;
2417 }
2418
2419 // Grab the state from the current block.
2420 block->copy_state_into(state);
2421 state->def_locals()->clear();
2422
2423 GrowableArray<Block*>* exceptions = block->exceptions();
2424 GrowableArray<ciInstanceKlass*>* exc_klasses = block->exc_klasses();
2425 bool has_exceptions = exceptions->length() > 0;
2426
2427 bool exceptions_used = false;
2428
2429 ciBytecodeStream str(method());
2430 str.reset_to_bci(start);
2431 Bytecodes::Code code;
2432 while ((code = str.next()) != ciBytecodeStream::EOBC() &&
2433 str.cur_bci() < limit) {
2434 // Check for exceptional control flow from this point.
2435 if (has_exceptions && can_trap(str)) {
2436 flow_exceptions(exceptions, exc_klasses, state);
2437 exceptions_used = true;
2438 }
2439 // Apply the effects of the current bytecode to our state.
2440 bool res = state->apply_one_bytecode(&str);
2441
2442 // Watch for bailouts.
2443 if (failing()) return;
2444
2445 if (str.cur_bc() == Bytecodes::_monitorenter) {
2446 block->set_has_monitorenter();
2447 }
2448
2449 if (res) {
2450
2451 // We have encountered a trap. Record it in this block.
2452 block->set_trap(state->trap_bci(), state->trap_index());
2453
2454 if (CITraceTypeFlow) {
2455 tty->print_cr(">> Found trap");
2456 block->print_on(tty);
2457 }
2458
2459 // Save set of locals defined in this block
2460 block->def_locals()->add(state->def_locals());
2461
2462 // Record (no) successors.
2463 block->successors(&str, state, jsrs);
2464
2465 assert(!has_exceptions || exceptions_used, "Not removing exceptions");
2466
2467 // Discontinue interpretation of this Block.
2468 return;
2469 }
2470 }
2471
2472 GrowableArray<Block*>* successors = NULL;
2473 if (control != ciBlock::fall_through_bci) {
2474 // Check for exceptional control flow from this point.
2475 if (has_exceptions && can_trap(str)) {
2476 flow_exceptions(exceptions, exc_klasses, state);
2477 exceptions_used = true;
2478 }
2479
2480 // Fix the JsrSet to reflect effect of the bytecode.
2481 block->copy_jsrs_into(jsrs);
2482 jsrs->apply_control(this, &str, state);
2483
2484 // Find successor edges based on old state and new JsrSet.
2485 successors = block->successors(&str, state, jsrs);
2486
2487 // Apply the control changes to the state.
2488 state->apply_one_bytecode(&str);
2489 } else {
2490 // Fall through control
2491 successors = block->successors(&str, NULL, NULL);
2492 }
2493
2494 // Save set of locals defined in this block
2495 block->def_locals()->add(state->def_locals());
2496
2497 // Remove untaken exception paths
2498 if (!exceptions_used)
2499 exceptions->clear();
2500
2501 // Pass our state to successors.
2502 flow_successors(successors, state);
2503 }
2504
2505 // ------------------------------------------------------------------
2506 // ciTypeFlow::PostOrderLoops::next
2507 //
2508 // Advance to next loop tree using a postorder, left-to-right traversal.
2509 void ciTypeFlow::PostorderLoops::next() {
2510 assert(!done(), "must not be done.");
2511 if (_current->sibling() != NULL) {
2512 _current = _current->sibling();
2513 while (_current->child() != NULL) {
2514 _current = _current->child();
2515 }
2516 } else {
2517 _current = _current->parent();
2518 }
2519 }
2520
2521 // ------------------------------------------------------------------
2522 // ciTypeFlow::PreOrderLoops::next
2523 //
2524 // Advance to next loop tree using a preorder, left-to-right traversal.
2525 void ciTypeFlow::PreorderLoops::next() {
2526 assert(!done(), "must not be done.");
2527 if (_current->child() != NULL) {
2528 _current = _current->child();
2529 } else if (_current->sibling() != NULL) {
2530 _current = _current->sibling();
2531 } else {
2532 while (_current != _root && _current->sibling() == NULL) {
2533 _current = _current->parent();
2534 }
2535 if (_current == _root) {
2536 _current = NULL;
2537 assert(done(), "must be done.");
2538 } else {
2539 assert(_current->sibling() != NULL, "must be more to do");
2540 _current = _current->sibling();
2541 }
2542 }
2543 }
2544
2545 // ------------------------------------------------------------------
2546 // ciTypeFlow::Loop::sorted_merge
2547 //
2548 // Merge the branch lp into this branch, sorting on the loop head
2549 // pre_orders. Returns the leaf of the merged branch.
2550 // Child and sibling pointers will be setup later.
2551 // Sort is (looking from leaf towards the root)
2552 // descending on primary key: loop head's pre_order, and
2553 // ascending on secondary key: loop tail's pre_order.
2554 ciTypeFlow::Loop* ciTypeFlow::Loop::sorted_merge(Loop* lp) {
2555 Loop* leaf = this;
2556 Loop* prev = NULL;
2557 Loop* current = leaf;
2558 while (lp != NULL) {
2559 int lp_pre_order = lp->head()->pre_order();
2560 // Find insertion point for "lp"
2561 while (current != NULL) {
2562 if (current == lp)
2563 return leaf; // Already in list
2564 if (current->head()->pre_order() < lp_pre_order)
2565 break;
2566 if (current->head()->pre_order() == lp_pre_order &&
2567 current->tail()->pre_order() > lp->tail()->pre_order()) {
2568 break;
2569 }
2570 prev = current;
2571 current = current->parent();
2572 }
2573 Loop* next_lp = lp->parent(); // Save future list of items to insert
2574 // Insert lp before current
2575 lp->set_parent(current);
2576 if (prev != NULL) {
2577 prev->set_parent(lp);
2578 } else {
2579 leaf = lp;
2580 }
2581 prev = lp; // Inserted item is new prev[ious]
2582 lp = next_lp; // Next item to insert
2583 }
2584 return leaf;
2585 }
2586
2587 // ------------------------------------------------------------------
2588 // ciTypeFlow::build_loop_tree
2589 //
2590 // Incrementally build loop tree.
2591 void ciTypeFlow::build_loop_tree(Block* blk) {
2592 assert(!blk->is_post_visited(), "precondition");
2593 Loop* innermost = NULL; // merge of loop tree branches over all successors
2594
2595 for (SuccIter iter(blk); !iter.done(); iter.next()) {
2596 Loop* lp = NULL;
2597 Block* succ = iter.succ();
2598 if (!succ->is_post_visited()) {
2599 // Found backedge since predecessor post visited, but successor is not
2600 assert(succ->pre_order() <= blk->pre_order(), "should be backedge");
2601
2602 // Create a LoopNode to mark this loop.
2603 lp = new (arena()) Loop(succ, blk);
2604 if (succ->loop() == NULL)
2605 succ->set_loop(lp);
2606 // succ->loop will be updated to innermost loop on a later call, when blk==succ
2607
2608 } else { // Nested loop
2609 lp = succ->loop();
2610
2611 // If succ is loop head, find outer loop.
2612 while (lp != NULL && lp->head() == succ) {
2613 lp = lp->parent();
2614 }
2615 if (lp == NULL) {
2616 // Infinite loop, it's parent is the root
2617 lp = loop_tree_root();
2618 }
2619 }
2620
2621 // Check for irreducible loop.
2622 // Successor has already been visited. If the successor's loop head
2623 // has already been post-visited, then this is another entry into the loop.
2624 while (lp->head()->is_post_visited() && lp != loop_tree_root()) {
2625 _has_irreducible_entry = true;
2626 lp->set_irreducible(succ);
2627 if (!succ->is_on_work_list()) {
2628 // Assume irreducible entries need more data flow
2629 add_to_work_list(succ);
2630 }
2631 Loop* plp = lp->parent();
2632 if (plp == NULL) {
2633 // This only happens for some irreducible cases. The parent
2634 // will be updated during a later pass.
2635 break;
2636 }
2637 lp = plp;
2638 }
2639
2640 // Merge loop tree branch for all successors.
2641 innermost = innermost == NULL ? lp : innermost->sorted_merge(lp);
2642
2643 } // end loop
2644
2645 if (innermost == NULL) {
2646 assert(blk->successors()->length() == 0, "CFG exit");
2647 blk->set_loop(loop_tree_root());
2648 } else if (innermost->head() == blk) {
2649 // If loop header, complete the tree pointers
2650 if (blk->loop() != innermost) {
2651 #ifdef ASSERT
2652 assert(blk->loop()->head() == innermost->head(), "same head");
2653 Loop* dl;
2654 for (dl = innermost; dl != NULL && dl != blk->loop(); dl = dl->parent());
2655 assert(dl == blk->loop(), "blk->loop() already in innermost list");
2656 #endif
2657 blk->set_loop(innermost);
2658 }
2659 innermost->def_locals()->add(blk->def_locals());
2660 Loop* l = innermost;
2661 Loop* p = l->parent();
2662 while (p && l->head() == blk) {
2663 l->set_sibling(p->child()); // Put self on parents 'next child'
2664 p->set_child(l); // Make self the first child of parent
2665 p->def_locals()->add(l->def_locals());
2666 l = p; // Walk up the parent chain
2667 p = l->parent();
2668 }
2669 } else {
2670 blk->set_loop(innermost);
2671 innermost->def_locals()->add(blk->def_locals());
2672 }
2673 }
2674
2675 // ------------------------------------------------------------------
2676 // ciTypeFlow::Loop::contains
2677 //
2678 // Returns true if lp is nested loop.
2679 bool ciTypeFlow::Loop::contains(ciTypeFlow::Loop* lp) const {
2680 assert(lp != NULL, "");
2681 if (this == lp || head() == lp->head()) return true;
2682 int depth1 = depth();
2683 int depth2 = lp->depth();
2684 if (depth1 > depth2)
2685 return false;
2686 while (depth1 < depth2) {
2687 depth2--;
2688 lp = lp->parent();
2689 }
2690 return this == lp;
2691 }
2692
2693 // ------------------------------------------------------------------
2694 // ciTypeFlow::Loop::depth
2695 //
2696 // Loop depth
2697 int ciTypeFlow::Loop::depth() const {
2698 int dp = 0;
2699 for (Loop* lp = this->parent(); lp != NULL; lp = lp->parent())
2700 dp++;
2701 return dp;
2702 }
2703
2704 #ifndef PRODUCT
2705 // ------------------------------------------------------------------
2706 // ciTypeFlow::Loop::print
2707 void ciTypeFlow::Loop::print(outputStream* st, int indent) const {
2708 for (int i = 0; i < indent; i++) st->print(" ");
2709 st->print("%d<-%d %s",
2710 is_root() ? 0 : this->head()->pre_order(),
2711 is_root() ? 0 : this->tail()->pre_order(),
2712 is_irreducible()?" irr":"");
2713 st->print(" defs: ");
2714 def_locals()->print_on(st, _head->outer()->method()->max_locals());
2715 st->cr();
2716 for (Loop* ch = child(); ch != NULL; ch = ch->sibling())
2717 ch->print(st, indent+2);
2718 }
2719 #endif
2720
2721 // ------------------------------------------------------------------
2722 // ciTypeFlow::df_flow_types
2723 //
2724 // Perform the depth first type flow analysis. Helper for flow_types.
2725 void ciTypeFlow::df_flow_types(Block* start,
2726 bool do_flow,
2727 StateVector* temp_vector,
2728 JsrSet* temp_set) {
2729 int dft_len = 100;
2730 GrowableArray<Block*> stk(dft_len);
2731
2732 ciBlock* dummy = _methodBlocks->make_dummy_block();
2733 JsrSet* root_set = new JsrSet(NULL, 0);
2734 Block* root_head = new (arena()) Block(this, dummy, root_set);
2735 Block* root_tail = new (arena()) Block(this, dummy, root_set);
2736 root_head->set_pre_order(0);
2737 root_head->set_post_order(0);
2738 root_tail->set_pre_order(max_jint);
2739 root_tail->set_post_order(max_jint);
2740 set_loop_tree_root(new (arena()) Loop(root_head, root_tail));
2741
2742 stk.push(start);
2743
2744 _next_pre_order = 0; // initialize pre_order counter
2745 _rpo_list = NULL;
2746 int next_po = 0; // initialize post_order counter
2747
2748 // Compute RPO and the control flow graph
2749 int size;
2750 while ((size = stk.length()) > 0) {
2751 Block* blk = stk.top(); // Leave node on stack
2752 if (!blk->is_visited()) {
2753 // forward arc in graph
2754 assert (!blk->has_pre_order(), "");
2755 blk->set_next_pre_order();
2756
2757 if (_next_pre_order >= (int)Compile::current()->max_node_limit() / 2) {
2758 // Too many basic blocks. Bail out.
2759 // This can happen when try/finally constructs are nested to depth N,
2760 // and there is O(2**N) cloning of jsr bodies. See bug 4697245!
2761 // "MaxNodeLimit / 2" is used because probably the parser will
2762 // generate at least twice that many nodes and bail out.
2763 record_failure("too many basic blocks");
2764 return;
2765 }
2766 if (do_flow) {
2767 flow_block(blk, temp_vector, temp_set);
2768 if (failing()) return; // Watch for bailouts.
2769 }
2770 } else if (!blk->is_post_visited()) {
2771 // cross or back arc
2772 for (SuccIter iter(blk); !iter.done(); iter.next()) {
2773 Block* succ = iter.succ();
2774 if (!succ->is_visited()) {
2775 stk.push(succ);
2776 }
2777 }
2778 if (stk.length() == size) {
2779 // There were no additional children, post visit node now
2780 stk.pop(); // Remove node from stack
2781
2782 build_loop_tree(blk);
2783 blk->set_post_order(next_po++); // Assign post order
2784 prepend_to_rpo_list(blk);
2785 assert(blk->is_post_visited(), "");
2786
2787 if (blk->is_loop_head() && !blk->is_on_work_list()) {
2788 // Assume loop heads need more data flow
2789 add_to_work_list(blk);
2790 }
2791 }
2792 } else {
2793 stk.pop(); // Remove post-visited node from stack
2794 }
2795 }
2796 }
2797
2798 // ------------------------------------------------------------------
2799 // ciTypeFlow::flow_types
2800 //
2801 // Perform the type flow analysis, creating and cloning Blocks as
2802 // necessary.
2803 void ciTypeFlow::flow_types() {
2804 ResourceMark rm;
2805 StateVector* temp_vector = new StateVector(this);
2806 JsrSet* temp_set = new JsrSet(NULL, 16);
2807
2808 // Create the method entry block.
2809 Block* start = block_at(start_bci(), temp_set);
2810
2811 // Load the initial state into it.
2812 const StateVector* start_state = get_start_state();
2813 if (failing()) return;
2814 start->meet(start_state);
2815
2816 // Depth first visit
2817 df_flow_types(start, true /*do flow*/, temp_vector, temp_set);
2818
2819 if (failing()) return;
2820 assert(_rpo_list == start, "must be start");
2821
2822 // Any loops found?
2823 if (loop_tree_root()->child() != NULL &&
2824 env()->comp_level() >= CompLevel_full_optimization) {
2825 // Loop optimizations are not performed on Tier1 compiles.
2826
2827 bool changed = clone_loop_heads(loop_tree_root(), temp_vector, temp_set);
2828
2829 // If some loop heads were cloned, recompute postorder and loop tree
2830 if (changed) {
2831 loop_tree_root()->set_child(NULL);
2832 for (Block* blk = _rpo_list; blk != NULL;) {
2833 Block* next = blk->rpo_next();
2834 blk->df_init();
2835 blk = next;
2836 }
2837 df_flow_types(start, false /*no flow*/, temp_vector, temp_set);
2838 }
2839 }
2840
2841 if (CITraceTypeFlow) {
2842 tty->print_cr("\nLoop tree");
2843 loop_tree_root()->print();
2844 }
2845
2846 // Continue flow analysis until fixed point reached
2847
2848 debug_only(int max_block = _next_pre_order;)
2849
2850 while (!work_list_empty()) {
2851 Block* blk = work_list_next();
2852 assert (blk->has_post_order(), "post order assigned above");
2853
2854 flow_block(blk, temp_vector, temp_set);
2855
2856 assert (max_block == _next_pre_order, "no new blocks");
2857 assert (!failing(), "no more bailouts");
2858 }
2859 }
2860
2861 // ------------------------------------------------------------------
2862 // ciTypeFlow::map_blocks
2863 //
2864 // Create the block map, which indexes blocks in reverse post-order.
2865 void ciTypeFlow::map_blocks() {
2866 assert(_block_map == NULL, "single initialization");
2867 int block_ct = _next_pre_order;
2868 _block_map = NEW_ARENA_ARRAY(arena(), Block*, block_ct);
2869 assert(block_ct == block_count(), "");
2870
2871 Block* blk = _rpo_list;
2872 for (int m = 0; m < block_ct; m++) {
2873 int rpo = blk->rpo();
2874 assert(rpo == m, "should be sequential");
2875 _block_map[rpo] = blk;
2876 blk = blk->rpo_next();
2877 }
2878 assert(blk == NULL, "should be done");
2879
2880 for (int j = 0; j < block_ct; j++) {
2881 assert(_block_map[j] != NULL, "must not drop any blocks");
2882 Block* block = _block_map[j];
2883 // Remove dead blocks from successor lists:
2884 for (int e = 0; e <= 1; e++) {
2885 GrowableArray<Block*>* l = e? block->exceptions(): block->successors();
2886 for (int k = 0; k < l->length(); k++) {
2887 Block* s = l->at(k);
2888 if (!s->has_post_order()) {
2889 if (CITraceTypeFlow) {
2890 tty->print("Removing dead %s successor of #%d: ", (e? "exceptional": "normal"), block->pre_order());
2891 s->print_value_on(tty);
2892 tty->cr();
2893 }
2894 l->remove(s);
2895 --k;
2896 }
2897 }
2898 }
2899 }
2900 }
2901
2902 // ------------------------------------------------------------------
2903 // ciTypeFlow::get_block_for
2904 //
2905 // Find a block with this ciBlock which has a compatible JsrSet.
2906 // If no such block exists, create it, unless the option is no_create.
2907 // If the option is create_backedge_copy, always create a fresh backedge copy.
2908 ciTypeFlow::Block* ciTypeFlow::get_block_for(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
2909 Arena* a = arena();
2910 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
2911 if (blocks == NULL) {
2912 // Query only?
2913 if (option == no_create) return NULL;
2914
2915 // Allocate the growable array.
2916 blocks = new (a) GrowableArray<Block*>(a, 4, 0, NULL);
2917 _idx_to_blocklist[ciBlockIndex] = blocks;
2918 }
2919
2920 if (option != create_backedge_copy) {
2921 int len = blocks->length();
2922 for (int i = 0; i < len; i++) {
2923 Block* block = blocks->at(i);
2924 if (!block->is_backedge_copy() && block->is_compatible_with(jsrs)) {
2925 return block;
2926 }
2927 }
2928 }
2929
2930 // Query only?
2931 if (option == no_create) return NULL;
2932
2933 // We did not find a compatible block. Create one.
2934 Block* new_block = new (a) Block(this, _methodBlocks->block(ciBlockIndex), jsrs);
2935 if (option == create_backedge_copy) new_block->set_backedge_copy(true);
2936 blocks->append(new_block);
2937 return new_block;
2938 }
2939
2940 // ------------------------------------------------------------------
2941 // ciTypeFlow::backedge_copy_count
2942 //
2943 int ciTypeFlow::backedge_copy_count(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs) const {
2944 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
2945
2946 if (blocks == NULL) {
2947 return 0;
2948 }
2949
2950 int count = 0;
2951 int len = blocks->length();
2952 for (int i = 0; i < len; i++) {
2953 Block* block = blocks->at(i);
2954 if (block->is_backedge_copy() && block->is_compatible_with(jsrs)) {
2955 count++;
2956 }
2957 }
2958
2959 return count;
2960 }
2961
2962 // ------------------------------------------------------------------
2963 // ciTypeFlow::do_flow
2964 //
2965 // Perform type inference flow analysis.
2966 void ciTypeFlow::do_flow() {
2967 if (CITraceTypeFlow) {
2968 tty->print_cr("\nPerforming flow analysis on method");
2969 method()->print();
2970 if (is_osr_flow()) tty->print(" at OSR bci %d", start_bci());
2971 tty->cr();
2972 method()->print_codes();
2973 }
2974 if (CITraceTypeFlow) {
2975 tty->print_cr("Initial CI Blocks");
2976 print_on(tty);
2977 }
2978 flow_types();
2979 // Watch for bailouts.
2980 if (failing()) {
2981 return;
2982 }
2983
2984 map_blocks();
2985
2986 if (CIPrintTypeFlow || CITraceTypeFlow) {
2987 rpo_print_on(tty);
2988 }
2989 }
2990
2991 // ------------------------------------------------------------------
2992 // ciTypeFlow::is_dominated_by
2993 //
2994 // Determine if the instruction at bci is dominated by the instruction at dom_bci.
2995 bool ciTypeFlow::is_dominated_by(int bci, int dom_bci) {
2996 assert(!method()->has_jsrs(), "jsrs are not supported");
2997
2998 ResourceMark rm;
2999 JsrSet* jsrs = new ciTypeFlow::JsrSet(NULL);
3000 int index = _methodBlocks->block_containing(bci)->index();
3001 int dom_index = _methodBlocks->block_containing(dom_bci)->index();
3002 Block* block = get_block_for(index, jsrs, ciTypeFlow::no_create);
3003 Block* dom_block = get_block_for(dom_index, jsrs, ciTypeFlow::no_create);
3004
3005 // Start block dominates all other blocks
3006 if (start_block()->rpo() == dom_block->rpo()) {
3007 return true;
3008 }
3009
3010 // Dominated[i] is true if block i is dominated by dom_block
3011 int num_blocks = block_count();
3012 bool* dominated = NEW_RESOURCE_ARRAY(bool, num_blocks);
3013 for (int i = 0; i < num_blocks; ++i) {
3014 dominated[i] = true;
3015 }
3016 dominated[start_block()->rpo()] = false;
3017
3018 // Iterative dominator algorithm
3019 bool changed = true;
3020 while (changed) {
3021 changed = false;
3022 // Use reverse postorder iteration
3023 for (Block* blk = _rpo_list; blk != NULL; blk = blk->rpo_next()) {
3024 if (blk->is_start()) {
3025 // Ignore start block
3026 continue;
3027 }
3028 // The block is dominated if it is the dominating block
3029 // itself or if all predecessors are dominated.
3030 int index = blk->rpo();
3031 bool dom = (index == dom_block->rpo());
3032 if (!dom) {
3033 // Check if all predecessors are dominated
3034 dom = true;
3035 for (int i = 0; i < blk->predecessors()->length(); ++i) {
3036 Block* pred = blk->predecessors()->at(i);
3037 if (!dominated[pred->rpo()]) {
3038 dom = false;
3039 break;
3040 }
3041 }
3042 }
3043 // Update dominator information
3044 if (dominated[index] != dom) {
3045 changed = true;
3046 dominated[index] = dom;
3047 }
3048 }
3049 }
3050 // block dominated by dom_block?
3051 return dominated[block->rpo()];
3052 }
3053
3054 // ------------------------------------------------------------------
3055 // ciTypeFlow::record_failure()
3056 // The ciTypeFlow object keeps track of failure reasons separately from the ciEnv.
3057 // This is required because there is not a 1-1 relation between the ciEnv and
3058 // the TypeFlow passes within a compilation task. For example, if the compiler
3059 // is considering inlining a method, it will request a TypeFlow. If that fails,
3060 // the compilation as a whole may continue without the inlining. Some TypeFlow
3061 // requests are not optional; if they fail the requestor is responsible for
3062 // copying the failure reason up to the ciEnv. (See Parse::Parse.)
3063 void ciTypeFlow::record_failure(const char* reason) {
3064 if (env()->log() != NULL) {
3065 env()->log()->elem("failure reason='%s' phase='typeflow'", reason);
3066 }
3067 if (_failure_reason == NULL) {
3068 // Record the first failure reason.
3069 _failure_reason = reason;
3070 }
3071 }
3072
3073 #ifndef PRODUCT
3074 // ------------------------------------------------------------------
3075 // ciTypeFlow::print_on
3076 void ciTypeFlow::print_on(outputStream* st) const {
3077 // Walk through CI blocks
3078 st->print_cr("********************************************************");
3079 st->print ("TypeFlow for ");
3080 method()->name()->print_symbol_on(st);
3081 int limit_bci = code_size();
3082 st->print_cr(" %d bytes", limit_bci);
3083 ciMethodBlocks *mblks = _methodBlocks;
3084 ciBlock* current = NULL;
3085 for (int bci = 0; bci < limit_bci; bci++) {
3086 ciBlock* blk = mblks->block_containing(bci);
3087 if (blk != NULL && blk != current) {
3088 current = blk;
3089 current->print_on(st);
3090
3091 GrowableArray<Block*>* blocks = _idx_to_blocklist[blk->index()];
3092 int num_blocks = (blocks == NULL) ? 0 : blocks->length();
3093
3094 if (num_blocks == 0) {
3095 st->print_cr(" No Blocks");
3096 } else {
3097 for (int i = 0; i < num_blocks; i++) {
3098 Block* block = blocks->at(i);
3099 block->print_on(st);
3100 }
3101 }
3102 st->print_cr("--------------------------------------------------------");
3103 st->cr();
3104 }
3105 }
3106 st->print_cr("********************************************************");
3107 st->cr();
3108 }
3109
3110 void ciTypeFlow::rpo_print_on(outputStream* st) const {
3111 st->print_cr("********************************************************");
3112 st->print ("TypeFlow for ");
3113 method()->name()->print_symbol_on(st);
3114 int limit_bci = code_size();
3115 st->print_cr(" %d bytes", limit_bci);
3116 for (Block* blk = _rpo_list; blk != NULL; blk = blk->rpo_next()) {
3117 blk->print_on(st);
3118 st->print_cr("--------------------------------------------------------");
3119 st->cr();
3120 }
3121 st->print_cr("********************************************************");
3122 st->cr();
3123 }
3124 #endif