Mercurial > jdk8-mips64-public > hotspot / file revision
src/share/vm/ci/ciTypeFlow.cpp@a61af66fc99e
src/share/vm/ci/ciTypeFlow.cpp
Sat, 01 Dec 2007 00:00:00 +0000
- author
- duke
- date
- Sat, 01 Dec 2007 00:00:00 +0000
- changeset 435
- a61af66fc99e
- child 802
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1 /*
2 * Copyright 2000-2007 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 #include "incls/_precompiled.incl"
26 #include "incls/_ciTypeFlow.cpp.incl"
28 // ciTypeFlow::JsrSet
29 //
30 // A JsrSet represents some set of JsrRecords. This class
31 // is used to record a set of all jsr routines which we permit
32 // execution to return (ret) from.
33 //
34 // During abstract interpretation, JsrSets are used to determine
35 // whether two paths which reach a given block are unique, and
36 // should be cloned apart, or are compatible, and should merge
37 // together.
39 // ------------------------------------------------------------------
40 // ciTypeFlow::JsrSet::JsrSet
41 ciTypeFlow::JsrSet::JsrSet(Arena* arena, int default_len) {
42 if (arena != NULL) {
43 // Allocate growable array in Arena.
44 _set = new (arena) GrowableArray<JsrRecord*>(arena, default_len, 0, NULL);
45 } else {
46 // Allocate growable array in current ResourceArea.
47 _set = new GrowableArray<JsrRecord*>(4, 0, NULL, false);
48 }
49 }
51 // ------------------------------------------------------------------
52 // ciTypeFlow::JsrSet::copy_into
53 void ciTypeFlow::JsrSet::copy_into(JsrSet* jsrs) {
54 int len = size();
55 jsrs->_set->clear();
56 for (int i = 0; i < len; i++) {
57 jsrs->_set->append(_set->at(i));
58 }
59 }
61 // ------------------------------------------------------------------
62 // ciTypeFlow::JsrSet::is_compatible_with
63 //
64 // !!!! MISGIVINGS ABOUT THIS... disregard
65 //
66 // Is this JsrSet compatible with some other JsrSet?
67 //
68 // In set-theoretic terms, a JsrSet can be viewed as a partial function
69 // from entry addresses to return addresses. Two JsrSets A and B are
70 // compatible iff
71 //
72 // For any x,
73 // A(x) defined and B(x) defined implies A(x) == B(x)
74 //
75 // Less formally, two JsrSets are compatible when they have identical
76 // return addresses for any entry addresses they share in common.
77 bool ciTypeFlow::JsrSet::is_compatible_with(JsrSet* other) {
78 // Walk through both sets in parallel. If the same entry address
79 // appears in both sets, then the return address must match for
80 // the sets to be compatible.
81 int size1 = size();
82 int size2 = other->size();
84 // Special case. If nothing is on the jsr stack, then there can
85 // be no ret.
86 if (size2 == 0) {
87 return true;
88 } else if (size1 != size2) {
89 return false;
90 } else {
91 for (int i = 0; i < size1; i++) {
92 JsrRecord* record1 = record_at(i);
93 JsrRecord* record2 = other->record_at(i);
94 if (record1->entry_address() != record2->entry_address() ||
95 record1->return_address() != record2->return_address()) {
96 return false;
97 }
98 }
99 return true;
100 }
102 #if 0
103 int pos1 = 0;
104 int pos2 = 0;
105 int size1 = size();
106 int size2 = other->size();
107 while (pos1 < size1 && pos2 < size2) {
108 JsrRecord* record1 = record_at(pos1);
109 JsrRecord* record2 = other->record_at(pos2);
110 int entry1 = record1->entry_address();
111 int entry2 = record2->entry_address();
112 if (entry1 < entry2) {
113 pos1++;
114 } else if (entry1 > entry2) {
115 pos2++;
116 } else {
117 if (record1->return_address() == record2->return_address()) {
118 pos1++;
119 pos2++;
120 } else {
121 // These two JsrSets are incompatible.
122 return false;
123 }
124 }
125 }
126 // The two JsrSets agree.
127 return true;
128 #endif
129 }
131 // ------------------------------------------------------------------
132 // ciTypeFlow::JsrSet::insert_jsr_record
133 //
134 // Insert the given JsrRecord into the JsrSet, maintaining the order
135 // of the set and replacing any element with the same entry address.
136 void ciTypeFlow::JsrSet::insert_jsr_record(JsrRecord* record) {
137 int len = size();
138 int entry = record->entry_address();
139 int pos = 0;
140 for ( ; pos < len; pos++) {
141 JsrRecord* current = record_at(pos);
142 if (entry == current->entry_address()) {
143 // Stomp over this entry.
144 _set->at_put(pos, record);
145 assert(size() == len, "must be same size");
146 return;
147 } else if (entry < current->entry_address()) {
148 break;
149 }
150 }
152 // Insert the record into the list.
153 JsrRecord* swap = record;
154 JsrRecord* temp = NULL;
155 for ( ; pos < len; pos++) {
156 temp = _set->at(pos);
157 _set->at_put(pos, swap);
158 swap = temp;
159 }
160 _set->append(swap);
161 assert(size() == len+1, "must be larger");
162 }
164 // ------------------------------------------------------------------
165 // ciTypeFlow::JsrSet::remove_jsr_record
166 //
167 // Remove the JsrRecord with the given return address from the JsrSet.
168 void ciTypeFlow::JsrSet::remove_jsr_record(int return_address) {
169 int len = size();
170 for (int i = 0; i < len; i++) {
171 if (record_at(i)->return_address() == return_address) {
172 // We have found the proper entry. Remove it from the
173 // JsrSet and exit.
174 for (int j = i+1; j < len ; j++) {
175 _set->at_put(j-1, _set->at(j));
176 }
177 _set->trunc_to(len-1);
178 assert(size() == len-1, "must be smaller");
179 return;
180 }
181 }
182 assert(false, "verify: returning from invalid subroutine");
183 }
185 // ------------------------------------------------------------------
186 // ciTypeFlow::JsrSet::apply_control
187 //
188 // Apply the effect of a control-flow bytecode on the JsrSet. The
189 // only bytecodes that modify the JsrSet are jsr and ret.
190 void ciTypeFlow::JsrSet::apply_control(ciTypeFlow* analyzer,
191 ciBytecodeStream* str,
192 ciTypeFlow::StateVector* state) {
193 Bytecodes::Code code = str->cur_bc();
194 if (code == Bytecodes::_jsr) {
195 JsrRecord* record =
196 analyzer->make_jsr_record(str->get_dest(), str->next_bci());
197 insert_jsr_record(record);
198 } else if (code == Bytecodes::_jsr_w) {
199 JsrRecord* record =
200 analyzer->make_jsr_record(str->get_far_dest(), str->next_bci());
201 insert_jsr_record(record);
202 } else if (code == Bytecodes::_ret) {
203 Cell local = state->local(str->get_index());
204 ciType* return_address = state->type_at(local);
205 assert(return_address->is_return_address(), "verify: wrong type");
206 if (size() == 0) {
207 // Ret-state underflow: Hit a ret w/o any previous jsrs. Bail out.
208 // This can happen when a loop is inside a finally clause (4614060).
209 analyzer->record_failure("OSR in finally clause");
210 return;
211 }
212 remove_jsr_record(return_address->as_return_address()->bci());
213 }
214 }
216 #ifndef PRODUCT
217 // ------------------------------------------------------------------
218 // ciTypeFlow::JsrSet::print_on
219 void ciTypeFlow::JsrSet::print_on(outputStream* st) const {
220 st->print("{ ");
221 int num_elements = size();
222 if (num_elements > 0) {
223 int i = 0;
224 for( ; i < num_elements - 1; i++) {
225 _set->at(i)->print_on(st);
226 st->print(", ");
227 }
228 _set->at(i)->print_on(st);
229 st->print(" ");
230 }
231 st->print("}");
232 }
233 #endif
235 // ciTypeFlow::StateVector
236 //
237 // A StateVector summarizes the type information at some point in
238 // the program.
240 // ------------------------------------------------------------------
241 // ciTypeFlow::StateVector::type_meet
242 //
243 // Meet two types.
244 //
245 // The semi-lattice of types use by this analysis are modeled on those
246 // of the verifier. The lattice is as follows:
247 //
248 // top_type() >= all non-extremal types >= bottom_type
249 // and
250 // Every primitive type is comparable only with itself. The meet of
251 // reference types is determined by their kind: instance class,
252 // interface, or array class. The meet of two types of the same
253 // kind is their least common ancestor. The meet of two types of
254 // different kinds is always java.lang.Object.
255 ciType* ciTypeFlow::StateVector::type_meet_internal(ciType* t1, ciType* t2, ciTypeFlow* analyzer) {
256 assert(t1 != t2, "checked in caller");
257 if (t1->equals(top_type())) {
258 return t2;
259 } else if (t2->equals(top_type())) {
260 return t1;
261 } else if (t1->is_primitive_type() || t2->is_primitive_type()) {
262 // Special case null_type. null_type meet any reference type T
263 // is T. null_type meet null_type is null_type.
264 if (t1->equals(null_type())) {
265 if (!t2->is_primitive_type() || t2->equals(null_type())) {
266 return t2;
267 }
268 } else if (t2->equals(null_type())) {
269 if (!t1->is_primitive_type()) {
270 return t1;
271 }
272 }
274 // At least one of the two types is a non-top primitive type.
275 // The other type is not equal to it. Fall to bottom.
276 return bottom_type();
277 } else {
278 // Both types are non-top non-primitive types. That is,
279 // both types are either instanceKlasses or arrayKlasses.
280 ciKlass* object_klass = analyzer->env()->Object_klass();
281 ciKlass* k1 = t1->as_klass();
282 ciKlass* k2 = t2->as_klass();
283 if (k1->equals(object_klass) || k2->equals(object_klass)) {
284 return object_klass;
285 } else if (!k1->is_loaded() || !k2->is_loaded()) {
286 // Unloaded classes fall to java.lang.Object at a merge.
287 return object_klass;
288 } else if (k1->is_interface() != k2->is_interface()) {
289 // When an interface meets a non-interface, we get Object;
290 // This is what the verifier does.
291 return object_klass;
292 } else if (k1->is_array_klass() || k2->is_array_klass()) {
293 // When an array meets a non-array, we get Object.
294 // When objArray meets typeArray, we also get Object.
295 // And when typeArray meets different typeArray, we again get Object.
296 // But when objArray meets objArray, we look carefully at element types.
297 if (k1->is_obj_array_klass() && k2->is_obj_array_klass()) {
298 // Meet the element types, then construct the corresponding array type.
299 ciKlass* elem1 = k1->as_obj_array_klass()->element_klass();
300 ciKlass* elem2 = k2->as_obj_array_klass()->element_klass();
301 ciKlass* elem = type_meet_internal(elem1, elem2, analyzer)->as_klass();
302 // Do an easy shortcut if one type is a super of the other.
303 if (elem == elem1) {
304 assert(k1 == ciObjArrayKlass::make(elem), "shortcut is OK");
305 return k1;
306 } else if (elem == elem2) {
307 assert(k2 == ciObjArrayKlass::make(elem), "shortcut is OK");
308 return k2;
309 } else {
310 return ciObjArrayKlass::make(elem);
311 }
312 } else {
313 return object_klass;
314 }
315 } else {
316 // Must be two plain old instance klasses.
317 assert(k1->is_instance_klass(), "previous cases handle non-instances");
318 assert(k2->is_instance_klass(), "previous cases handle non-instances");
319 return k1->least_common_ancestor(k2);
320 }
321 }
322 }
325 // ------------------------------------------------------------------
326 // ciTypeFlow::StateVector::StateVector
327 //
328 // Build a new state vector
329 ciTypeFlow::StateVector::StateVector(ciTypeFlow* analyzer) {
330 _outer = analyzer;
331 _stack_size = -1;
332 _monitor_count = -1;
333 // Allocate the _types array
334 int max_cells = analyzer->max_cells();
335 _types = (ciType**)analyzer->arena()->Amalloc(sizeof(ciType*) * max_cells);
336 for (int i=0; i<max_cells; i++) {
337 _types[i] = top_type();
338 }
339 _trap_bci = -1;
340 _trap_index = 0;
341 }
343 // ------------------------------------------------------------------
344 // ciTypeFlow::get_start_state
345 //
346 // Set this vector to the method entry state.
347 const ciTypeFlow::StateVector* ciTypeFlow::get_start_state() {
348 StateVector* state = new StateVector(this);
349 if (is_osr_flow()) {
350 ciTypeFlow* non_osr_flow = method()->get_flow_analysis();
351 if (non_osr_flow->failing()) {
352 record_failure(non_osr_flow->failure_reason());
353 return NULL;
354 }
355 JsrSet* jsrs = new JsrSet(NULL, 16);
356 Block* non_osr_block = non_osr_flow->existing_block_at(start_bci(), jsrs);
357 if (non_osr_block == NULL) {
358 record_failure("cannot reach OSR point");
359 return NULL;
360 }
361 // load up the non-OSR state at this point
362 non_osr_block->copy_state_into(state);
363 int non_osr_start = non_osr_block->start();
364 if (non_osr_start != start_bci()) {
365 // must flow forward from it
366 if (CITraceTypeFlow) {
367 tty->print_cr(">> Interpreting pre-OSR block %d:", non_osr_start);
368 }
369 Block* block = block_at(non_osr_start, jsrs);
370 assert(block->limit() == start_bci(), "must flow forward to start");
371 flow_block(block, state, jsrs);
372 }
373 return state;
374 // Note: The code below would be an incorrect for an OSR flow,
375 // even if it were possible for an OSR entry point to be at bci zero.
376 }
377 // "Push" the method signature into the first few locals.
378 state->set_stack_size(-max_locals());
379 if (!method()->is_static()) {
380 state->push(method()->holder());
381 assert(state->tos() == state->local(0), "");
382 }
383 for (ciSignatureStream str(method()->signature());
384 !str.at_return_type();
385 str.next()) {
386 state->push_translate(str.type());
387 }
388 // Set the rest of the locals to bottom.
389 Cell cell = state->next_cell(state->tos());
390 state->set_stack_size(0);
391 int limit = state->limit_cell();
392 for (; cell < limit; cell = state->next_cell(cell)) {
393 state->set_type_at(cell, state->bottom_type());
394 }
395 // Lock an object, if necessary.
396 state->set_monitor_count(method()->is_synchronized() ? 1 : 0);
397 return state;
398 }
400 // ------------------------------------------------------------------
401 // ciTypeFlow::StateVector::copy_into
402 //
403 // Copy our value into some other StateVector
404 void ciTypeFlow::StateVector::copy_into(ciTypeFlow::StateVector* copy)
405 const {
406 copy->set_stack_size(stack_size());
407 copy->set_monitor_count(monitor_count());
408 Cell limit = limit_cell();
409 for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
410 copy->set_type_at(c, type_at(c));
411 }
412 }
414 // ------------------------------------------------------------------
415 // ciTypeFlow::StateVector::meet
416 //
417 // Meets this StateVector with another, destructively modifying this
418 // one. Returns true if any modification takes place.
419 bool ciTypeFlow::StateVector::meet(const ciTypeFlow::StateVector* incoming) {
420 if (monitor_count() == -1) {
421 set_monitor_count(incoming->monitor_count());
422 }
423 assert(monitor_count() == incoming->monitor_count(), "monitors must match");
425 if (stack_size() == -1) {
426 set_stack_size(incoming->stack_size());
427 Cell limit = limit_cell();
428 #ifdef ASSERT
429 { for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
430 assert(type_at(c) == top_type(), "");
431 } }
432 #endif
433 // Make a simple copy of the incoming state.
434 for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
435 set_type_at(c, incoming->type_at(c));
436 }
437 return true; // it is always different the first time
438 }
439 #ifdef ASSERT
440 if (stack_size() != incoming->stack_size()) {
441 _outer->method()->print_codes();
442 tty->print_cr("!!!! Stack size conflict");
443 tty->print_cr("Current state:");
444 print_on(tty);
445 tty->print_cr("Incoming state:");
446 ((StateVector*)incoming)->print_on(tty);
447 }
448 #endif
449 assert(stack_size() == incoming->stack_size(), "sanity");
451 bool different = false;
452 Cell limit = limit_cell();
453 for (Cell c = start_cell(); c < limit; c = next_cell(c)) {
454 ciType* t1 = type_at(c);
455 ciType* t2 = incoming->type_at(c);
456 if (!t1->equals(t2)) {
457 ciType* new_type = type_meet(t1, t2);
458 if (!t1->equals(new_type)) {
459 set_type_at(c, new_type);
460 different = true;
461 }
462 }
463 }
464 return different;
465 }
467 // ------------------------------------------------------------------
468 // ciTypeFlow::StateVector::meet_exception
469 //
470 // Meets this StateVector with another, destructively modifying this
471 // one. The incoming state is coming via an exception. Returns true
472 // if any modification takes place.
473 bool ciTypeFlow::StateVector::meet_exception(ciInstanceKlass* exc,
474 const ciTypeFlow::StateVector* incoming) {
475 if (monitor_count() == -1) {
476 set_monitor_count(incoming->monitor_count());
477 }
478 assert(monitor_count() == incoming->monitor_count(), "monitors must match");
480 if (stack_size() == -1) {
481 set_stack_size(1);
482 }
484 assert(stack_size() == 1, "must have one-element stack");
486 bool different = false;
488 // Meet locals from incoming array.
489 Cell limit = local(_outer->max_locals()-1);
490 for (Cell c = start_cell(); c <= limit; c = next_cell(c)) {
491 ciType* t1 = type_at(c);
492 ciType* t2 = incoming->type_at(c);
493 if (!t1->equals(t2)) {
494 ciType* new_type = type_meet(t1, t2);
495 if (!t1->equals(new_type)) {
496 set_type_at(c, new_type);
497 different = true;
498 }
499 }
500 }
502 // Handle stack separately. When an exception occurs, the
503 // only stack entry is the exception instance.
504 ciType* tos_type = type_at_tos();
505 if (!tos_type->equals(exc)) {
506 ciType* new_type = type_meet(tos_type, exc);
507 if (!tos_type->equals(new_type)) {
508 set_type_at_tos(new_type);
509 different = true;
510 }
511 }
513 return different;
514 }
516 // ------------------------------------------------------------------
517 // ciTypeFlow::StateVector::push_translate
518 void ciTypeFlow::StateVector::push_translate(ciType* type) {
519 BasicType basic_type = type->basic_type();
520 if (basic_type == T_BOOLEAN || basic_type == T_CHAR ||
521 basic_type == T_BYTE || basic_type == T_SHORT) {
522 push_int();
523 } else {
524 push(type);
525 if (type->is_two_word()) {
526 push(half_type(type));
527 }
528 }
529 }
531 // ------------------------------------------------------------------
532 // ciTypeFlow::StateVector::do_aaload
533 void ciTypeFlow::StateVector::do_aaload(ciBytecodeStream* str) {
534 pop_int();
535 ciObjArrayKlass* array_klass = pop_objArray();
536 if (array_klass == NULL) {
537 // Did aaload on a null reference; push a null and ignore the exception.
538 // This instruction will never continue normally. All we have to do
539 // is report a value that will meet correctly with any downstream
540 // reference types on paths that will truly be executed. This null type
541 // meets with any reference type to yield that same reference type.
542 // (The compiler will generate an unconditonal exception here.)
543 push(null_type());
544 return;
545 }
546 if (!array_klass->is_loaded()) {
547 // Only fails for some -Xcomp runs
548 trap(str, array_klass,
549 Deoptimization::make_trap_request
550 (Deoptimization::Reason_unloaded,
551 Deoptimization::Action_reinterpret));
552 return;
553 }
554 ciKlass* element_klass = array_klass->element_klass();
555 if (!element_klass->is_loaded() && element_klass->is_instance_klass()) {
556 Untested("unloaded array element class in ciTypeFlow");
557 trap(str, element_klass,
558 Deoptimization::make_trap_request
559 (Deoptimization::Reason_unloaded,
560 Deoptimization::Action_reinterpret));
561 } else {
562 push_object(element_klass);
563 }
564 }
567 // ------------------------------------------------------------------
568 // ciTypeFlow::StateVector::do_checkcast
569 void ciTypeFlow::StateVector::do_checkcast(ciBytecodeStream* str) {
570 bool will_link;
571 ciKlass* klass = str->get_klass(will_link);
572 if (!will_link) {
573 // VM's interpreter will not load 'klass' if object is NULL.
574 // Type flow after this block may still be needed in two situations:
575 // 1) C2 uses do_null_assert() and continues compilation for later blocks
576 // 2) C2 does an OSR compile in a later block (see bug 4778368).
577 pop_object();
578 do_null_assert(klass);
579 } else {
580 pop_object();
581 push_object(klass);
582 }
583 }
585 // ------------------------------------------------------------------
586 // ciTypeFlow::StateVector::do_getfield
587 void ciTypeFlow::StateVector::do_getfield(ciBytecodeStream* str) {
588 // could add assert here for type of object.
589 pop_object();
590 do_getstatic(str);
591 }
593 // ------------------------------------------------------------------
594 // ciTypeFlow::StateVector::do_getstatic
595 void ciTypeFlow::StateVector::do_getstatic(ciBytecodeStream* str) {
596 bool will_link;
597 ciField* field = str->get_field(will_link);
598 if (!will_link) {
599 trap(str, field->holder(), str->get_field_holder_index());
600 } else {
601 ciType* field_type = field->type();
602 if (!field_type->is_loaded()) {
603 // Normally, we need the field's type to be loaded if we are to
604 // do anything interesting with its value.
605 // We used to do this: trap(str, str->get_field_signature_index());
606 //
607 // There is one good reason not to trap here. Execution can
608 // get past this "getfield" or "getstatic" if the value of
609 // the field is null. As long as the value is null, the class
610 // does not need to be loaded! The compiler must assume that
611 // the value of the unloaded class reference is null; if the code
612 // ever sees a non-null value, loading has occurred.
613 //
614 // This actually happens often enough to be annoying. If the
615 // compiler throws an uncommon trap at this bytecode, you can
616 // get an endless loop of recompilations, when all the code
617 // needs to do is load a series of null values. Also, a trap
618 // here can make an OSR entry point unreachable, triggering the
619 // assert on non_osr_block in ciTypeFlow::get_start_state.
620 // (See bug 4379915.)
621 do_null_assert(field_type->as_klass());
622 } else {
623 push_translate(field_type);
624 }
625 }
626 }
628 // ------------------------------------------------------------------
629 // ciTypeFlow::StateVector::do_invoke
630 void ciTypeFlow::StateVector::do_invoke(ciBytecodeStream* str,
631 bool has_receiver) {
632 bool will_link;
633 ciMethod* method = str->get_method(will_link);
634 if (!will_link) {
635 // We weren't able to find the method.
636 ciKlass* unloaded_holder = method->holder();
637 trap(str, unloaded_holder, str->get_method_holder_index());
638 } else {
639 ciSignature* signature = method->signature();
640 ciSignatureStream sigstr(signature);
641 int arg_size = signature->size();
642 int stack_base = stack_size() - arg_size;
643 int i = 0;
644 for( ; !sigstr.at_return_type(); sigstr.next()) {
645 ciType* type = sigstr.type();
646 ciType* stack_type = type_at(stack(stack_base + i++));
647 // Do I want to check this type?
648 // assert(stack_type->is_subtype_of(type), "bad type for field value");
649 if (type->is_two_word()) {
650 ciType* stack_type2 = type_at(stack(stack_base + i++));
651 assert(stack_type2->equals(half_type(type)), "must be 2nd half");
652 }
653 }
654 assert(arg_size == i, "must match");
655 for (int j = 0; j < arg_size; j++) {
656 pop();
657 }
658 if (has_receiver) {
659 // Check this?
660 pop_object();
661 }
662 assert(!sigstr.is_done(), "must have return type");
663 ciType* return_type = sigstr.type();
664 if (!return_type->is_void()) {
665 if (!return_type->is_loaded()) {
666 // As in do_getstatic(), generally speaking, we need the return type to
667 // be loaded if we are to do anything interesting with its value.
668 // We used to do this: trap(str, str->get_method_signature_index());
669 //
670 // We do not trap here since execution can get past this invoke if
671 // the return value is null. As long as the value is null, the class
672 // does not need to be loaded! The compiler must assume that
673 // the value of the unloaded class reference is null; if the code
674 // ever sees a non-null value, loading has occurred.
675 //
676 // See do_getstatic() for similar explanation, as well as bug 4684993.
677 do_null_assert(return_type->as_klass());
678 } else {
679 push_translate(return_type);
680 }
681 }
682 }
683 }
685 // ------------------------------------------------------------------
686 // ciTypeFlow::StateVector::do_jsr
687 void ciTypeFlow::StateVector::do_jsr(ciBytecodeStream* str) {
688 push(ciReturnAddress::make(str->next_bci()));
689 }
691 // ------------------------------------------------------------------
692 // ciTypeFlow::StateVector::do_ldc
693 void ciTypeFlow::StateVector::do_ldc(ciBytecodeStream* str) {
694 ciConstant con = str->get_constant();
695 BasicType basic_type = con.basic_type();
696 if (basic_type == T_ILLEGAL) {
697 // OutOfMemoryError in the CI while loading constant
698 push_null();
699 outer()->record_failure("ldc did not link");
700 return;
701 }
702 if (basic_type == T_OBJECT || basic_type == T_ARRAY) {
703 ciObject* obj = con.as_object();
704 if (obj->is_null_object()) {
705 push_null();
706 } else if (obj->is_klass()) {
707 // The type of ldc <class> is java.lang.Class
708 push_object(outer()->env()->Class_klass());
709 } else {
710 push_object(obj->klass());
711 }
712 } else {
713 push_translate(ciType::make(basic_type));
714 }
715 }
717 // ------------------------------------------------------------------
718 // ciTypeFlow::StateVector::do_multianewarray
719 void ciTypeFlow::StateVector::do_multianewarray(ciBytecodeStream* str) {
720 int dimensions = str->get_dimensions();
721 bool will_link;
722 ciArrayKlass* array_klass = str->get_klass(will_link)->as_array_klass();
723 if (!will_link) {
724 trap(str, array_klass, str->get_klass_index());
725 } else {
726 for (int i = 0; i < dimensions; i++) {
727 pop_int();
728 }
729 push_object(array_klass);
730 }
731 }
733 // ------------------------------------------------------------------
734 // ciTypeFlow::StateVector::do_new
735 void ciTypeFlow::StateVector::do_new(ciBytecodeStream* str) {
736 bool will_link;
737 ciKlass* klass = str->get_klass(will_link);
738 if (!will_link) {
739 trap(str, klass, str->get_klass_index());
740 } else {
741 push_object(klass);
742 }
743 }
745 // ------------------------------------------------------------------
746 // ciTypeFlow::StateVector::do_newarray
747 void ciTypeFlow::StateVector::do_newarray(ciBytecodeStream* str) {
748 pop_int();
749 ciKlass* klass = ciTypeArrayKlass::make((BasicType)str->get_index());
750 push_object(klass);
751 }
753 // ------------------------------------------------------------------
754 // ciTypeFlow::StateVector::do_putfield
755 void ciTypeFlow::StateVector::do_putfield(ciBytecodeStream* str) {
756 do_putstatic(str);
757 if (_trap_bci != -1) return; // unloaded field holder, etc.
758 // could add assert here for type of object.
759 pop_object();
760 }
762 // ------------------------------------------------------------------
763 // ciTypeFlow::StateVector::do_putstatic
764 void ciTypeFlow::StateVector::do_putstatic(ciBytecodeStream* str) {
765 bool will_link;
766 ciField* field = str->get_field(will_link);
767 if (!will_link) {
768 trap(str, field->holder(), str->get_field_holder_index());
769 } else {
770 ciType* field_type = field->type();
771 ciType* type = pop_value();
772 // Do I want to check this type?
773 // assert(type->is_subtype_of(field_type), "bad type for field value");
774 if (field_type->is_two_word()) {
775 ciType* type2 = pop_value();
776 assert(type2->is_two_word(), "must be 2nd half");
777 assert(type == half_type(type2), "must be 2nd half");
778 }
779 }
780 }
782 // ------------------------------------------------------------------
783 // ciTypeFlow::StateVector::do_ret
784 void ciTypeFlow::StateVector::do_ret(ciBytecodeStream* str) {
785 Cell index = local(str->get_index());
787 ciType* address = type_at(index);
788 assert(address->is_return_address(), "bad return address");
789 set_type_at(index, bottom_type());
790 }
792 // ------------------------------------------------------------------
793 // ciTypeFlow::StateVector::trap
794 //
795 // Stop interpretation of this path with a trap.
796 void ciTypeFlow::StateVector::trap(ciBytecodeStream* str, ciKlass* klass, int index) {
797 _trap_bci = str->cur_bci();
798 _trap_index = index;
800 // Log information about this trap:
801 CompileLog* log = outer()->env()->log();
802 if (log != NULL) {
803 int mid = log->identify(outer()->method());
804 int kid = (klass == NULL)? -1: log->identify(klass);
805 log->begin_elem("uncommon_trap method='%d' bci='%d'", mid, str->cur_bci());
806 char buf[100];
807 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
808 index));
809 if (kid >= 0)
810 log->print(" klass='%d'", kid);
811 log->end_elem();
812 }
813 }
815 // ------------------------------------------------------------------
816 // ciTypeFlow::StateVector::do_null_assert
817 // Corresponds to graphKit::do_null_assert.
818 void ciTypeFlow::StateVector::do_null_assert(ciKlass* unloaded_klass) {
819 if (unloaded_klass->is_loaded()) {
820 // We failed to link, but we can still compute with this class,
821 // since it is loaded somewhere. The compiler will uncommon_trap
822 // if the object is not null, but the typeflow pass can not assume
823 // that the object will be null, otherwise it may incorrectly tell
824 // the parser that an object is known to be null. 4761344, 4807707
825 push_object(unloaded_klass);
826 } else {
827 // The class is not loaded anywhere. It is safe to model the
828 // null in the typestates, because we can compile in a null check
829 // which will deoptimize us if someone manages to load the
830 // class later.
831 push_null();
832 }
833 }
836 // ------------------------------------------------------------------
837 // ciTypeFlow::StateVector::apply_one_bytecode
838 //
839 // Apply the effect of one bytecode to this StateVector
840 bool ciTypeFlow::StateVector::apply_one_bytecode(ciBytecodeStream* str) {
841 _trap_bci = -1;
842 _trap_index = 0;
844 if (CITraceTypeFlow) {
845 tty->print_cr(">> Interpreting bytecode %d:%s", str->cur_bci(),
846 Bytecodes::name(str->cur_bc()));
847 }
849 switch(str->cur_bc()) {
850 case Bytecodes::_aaload: do_aaload(str); break;
852 case Bytecodes::_aastore:
853 {
854 pop_object();
855 pop_int();
856 pop_objArray();
857 break;
858 }
859 case Bytecodes::_aconst_null:
860 {
861 push_null();
862 break;
863 }
864 case Bytecodes::_aload: load_local_object(str->get_index()); break;
865 case Bytecodes::_aload_0: load_local_object(0); break;
866 case Bytecodes::_aload_1: load_local_object(1); break;
867 case Bytecodes::_aload_2: load_local_object(2); break;
868 case Bytecodes::_aload_3: load_local_object(3); break;
870 case Bytecodes::_anewarray:
871 {
872 pop_int();
873 bool will_link;
874 ciKlass* element_klass = str->get_klass(will_link);
875 if (!will_link) {
876 trap(str, element_klass, str->get_klass_index());
877 } else {
878 push_object(ciObjArrayKlass::make(element_klass));
879 }
880 break;
881 }
882 case Bytecodes::_areturn:
883 case Bytecodes::_ifnonnull:
884 case Bytecodes::_ifnull:
885 {
886 pop_object();
887 break;
888 }
889 case Bytecodes::_monitorenter:
890 {
891 pop_object();
892 set_monitor_count(monitor_count() + 1);
893 break;
894 }
895 case Bytecodes::_monitorexit:
896 {
897 pop_object();
898 assert(monitor_count() > 0, "must be a monitor to exit from");
899 set_monitor_count(monitor_count() - 1);
900 break;
901 }
902 case Bytecodes::_arraylength:
903 {
904 pop_array();
905 push_int();
906 break;
907 }
908 case Bytecodes::_astore: store_local_object(str->get_index()); break;
909 case Bytecodes::_astore_0: store_local_object(0); break;
910 case Bytecodes::_astore_1: store_local_object(1); break;
911 case Bytecodes::_astore_2: store_local_object(2); break;
912 case Bytecodes::_astore_3: store_local_object(3); break;
914 case Bytecodes::_athrow:
915 {
916 NEEDS_CLEANUP;
917 pop_object();
918 break;
919 }
920 case Bytecodes::_baload:
921 case Bytecodes::_caload:
922 case Bytecodes::_iaload:
923 case Bytecodes::_saload:
924 {
925 pop_int();
926 ciTypeArrayKlass* array_klass = pop_typeArray();
927 // Put assert here for right type?
928 push_int();
929 break;
930 }
931 case Bytecodes::_bastore:
932 case Bytecodes::_castore:
933 case Bytecodes::_iastore:
934 case Bytecodes::_sastore:
935 {
936 pop_int();
937 pop_int();
938 pop_typeArray();
939 // assert here?
940 break;
941 }
942 case Bytecodes::_bipush:
943 case Bytecodes::_iconst_m1:
944 case Bytecodes::_iconst_0:
945 case Bytecodes::_iconst_1:
946 case Bytecodes::_iconst_2:
947 case Bytecodes::_iconst_3:
948 case Bytecodes::_iconst_4:
949 case Bytecodes::_iconst_5:
950 case Bytecodes::_sipush:
951 {
952 push_int();
953 break;
954 }
955 case Bytecodes::_checkcast: do_checkcast(str); break;
957 case Bytecodes::_d2f:
958 {
959 pop_double();
960 push_float();
961 break;
962 }
963 case Bytecodes::_d2i:
964 {
965 pop_double();
966 push_int();
967 break;
968 }
969 case Bytecodes::_d2l:
970 {
971 pop_double();
972 push_long();
973 break;
974 }
975 case Bytecodes::_dadd:
976 case Bytecodes::_ddiv:
977 case Bytecodes::_dmul:
978 case Bytecodes::_drem:
979 case Bytecodes::_dsub:
980 {
981 pop_double();
982 pop_double();
983 push_double();
984 break;
985 }
986 case Bytecodes::_daload:
987 {
988 pop_int();
989 ciTypeArrayKlass* array_klass = pop_typeArray();
990 // Put assert here for right type?
991 push_double();
992 break;
993 }
994 case Bytecodes::_dastore:
995 {
996 pop_double();
997 pop_int();
998 pop_typeArray();
999 // assert here?
1000 break;
1001 }
1002 case Bytecodes::_dcmpg:
1003 case Bytecodes::_dcmpl:
1004 {
1005 pop_double();
1006 pop_double();
1007 push_int();
1008 break;
1009 }
1010 case Bytecodes::_dconst_0:
1011 case Bytecodes::_dconst_1:
1012 {
1013 push_double();
1014 break;
1015 }
1016 case Bytecodes::_dload: load_local_double(str->get_index()); break;
1017 case Bytecodes::_dload_0: load_local_double(0); break;
1018 case Bytecodes::_dload_1: load_local_double(1); break;
1019 case Bytecodes::_dload_2: load_local_double(2); break;
1020 case Bytecodes::_dload_3: load_local_double(3); break;
1022 case Bytecodes::_dneg:
1023 {
1024 pop_double();
1025 push_double();
1026 break;
1027 }
1028 case Bytecodes::_dreturn:
1029 {
1030 pop_double();
1031 break;
1032 }
1033 case Bytecodes::_dstore: store_local_double(str->get_index()); break;
1034 case Bytecodes::_dstore_0: store_local_double(0); break;
1035 case Bytecodes::_dstore_1: store_local_double(1); break;
1036 case Bytecodes::_dstore_2: store_local_double(2); break;
1037 case Bytecodes::_dstore_3: store_local_double(3); break;
1039 case Bytecodes::_dup:
1040 {
1041 push(type_at_tos());
1042 break;
1043 }
1044 case Bytecodes::_dup_x1:
1045 {
1046 ciType* value1 = pop_value();
1047 ciType* value2 = pop_value();
1048 push(value1);
1049 push(value2);
1050 push(value1);
1051 break;
1052 }
1053 case Bytecodes::_dup_x2:
1054 {
1055 ciType* value1 = pop_value();
1056 ciType* value2 = pop_value();
1057 ciType* value3 = pop_value();
1058 push(value1);
1059 push(value3);
1060 push(value2);
1061 push(value1);
1062 break;
1063 }
1064 case Bytecodes::_dup2:
1065 {
1066 ciType* value1 = pop_value();
1067 ciType* value2 = pop_value();
1068 push(value2);
1069 push(value1);
1070 push(value2);
1071 push(value1);
1072 break;
1073 }
1074 case Bytecodes::_dup2_x1:
1075 {
1076 ciType* value1 = pop_value();
1077 ciType* value2 = pop_value();
1078 ciType* value3 = pop_value();
1079 push(value2);
1080 push(value1);
1081 push(value3);
1082 push(value2);
1083 push(value1);
1084 break;
1085 }
1086 case Bytecodes::_dup2_x2:
1087 {
1088 ciType* value1 = pop_value();
1089 ciType* value2 = pop_value();
1090 ciType* value3 = pop_value();
1091 ciType* value4 = pop_value();
1092 push(value2);
1093 push(value1);
1094 push(value4);
1095 push(value3);
1096 push(value2);
1097 push(value1);
1098 break;
1099 }
1100 case Bytecodes::_f2d:
1101 {
1102 pop_float();
1103 push_double();
1104 break;
1105 }
1106 case Bytecodes::_f2i:
1107 {
1108 pop_float();
1109 push_int();
1110 break;
1111 }
1112 case Bytecodes::_f2l:
1113 {
1114 pop_float();
1115 push_long();
1116 break;
1117 }
1118 case Bytecodes::_fadd:
1119 case Bytecodes::_fdiv:
1120 case Bytecodes::_fmul:
1121 case Bytecodes::_frem:
1122 case Bytecodes::_fsub:
1123 {
1124 pop_float();
1125 pop_float();
1126 push_float();
1127 break;
1128 }
1129 case Bytecodes::_faload:
1130 {
1131 pop_int();
1132 ciTypeArrayKlass* array_klass = pop_typeArray();
1133 // Put assert here.
1134 push_float();
1135 break;
1136 }
1137 case Bytecodes::_fastore:
1138 {
1139 pop_float();
1140 pop_int();
1141 ciTypeArrayKlass* array_klass = pop_typeArray();
1142 // Put assert here.
1143 break;
1144 }
1145 case Bytecodes::_fcmpg:
1146 case Bytecodes::_fcmpl:
1147 {
1148 pop_float();
1149 pop_float();
1150 push_int();
1151 break;
1152 }
1153 case Bytecodes::_fconst_0:
1154 case Bytecodes::_fconst_1:
1155 case Bytecodes::_fconst_2:
1156 {
1157 push_float();
1158 break;
1159 }
1160 case Bytecodes::_fload: load_local_float(str->get_index()); break;
1161 case Bytecodes::_fload_0: load_local_float(0); break;
1162 case Bytecodes::_fload_1: load_local_float(1); break;
1163 case Bytecodes::_fload_2: load_local_float(2); break;
1164 case Bytecodes::_fload_3: load_local_float(3); break;
1166 case Bytecodes::_fneg:
1167 {
1168 pop_float();
1169 push_float();
1170 break;
1171 }
1172 case Bytecodes::_freturn:
1173 {
1174 pop_float();
1175 break;
1176 }
1177 case Bytecodes::_fstore: store_local_float(str->get_index()); break;
1178 case Bytecodes::_fstore_0: store_local_float(0); break;
1179 case Bytecodes::_fstore_1: store_local_float(1); break;
1180 case Bytecodes::_fstore_2: store_local_float(2); break;
1181 case Bytecodes::_fstore_3: store_local_float(3); break;
1183 case Bytecodes::_getfield: do_getfield(str); break;
1184 case Bytecodes::_getstatic: do_getstatic(str); break;
1186 case Bytecodes::_goto:
1187 case Bytecodes::_goto_w:
1188 case Bytecodes::_nop:
1189 case Bytecodes::_return:
1190 {
1191 // do nothing.
1192 break;
1193 }
1194 case Bytecodes::_i2b:
1195 case Bytecodes::_i2c:
1196 case Bytecodes::_i2s:
1197 case Bytecodes::_ineg:
1198 {
1199 pop_int();
1200 push_int();
1201 break;
1202 }
1203 case Bytecodes::_i2d:
1204 {
1205 pop_int();
1206 push_double();
1207 break;
1208 }
1209 case Bytecodes::_i2f:
1210 {
1211 pop_int();
1212 push_float();
1213 break;
1214 }
1215 case Bytecodes::_i2l:
1216 {
1217 pop_int();
1218 push_long();
1219 break;
1220 }
1221 case Bytecodes::_iadd:
1222 case Bytecodes::_iand:
1223 case Bytecodes::_idiv:
1224 case Bytecodes::_imul:
1225 case Bytecodes::_ior:
1226 case Bytecodes::_irem:
1227 case Bytecodes::_ishl:
1228 case Bytecodes::_ishr:
1229 case Bytecodes::_isub:
1230 case Bytecodes::_iushr:
1231 case Bytecodes::_ixor:
1232 {
1233 pop_int();
1234 pop_int();
1235 push_int();
1236 break;
1237 }
1238 case Bytecodes::_if_acmpeq:
1239 case Bytecodes::_if_acmpne:
1240 {
1241 pop_object();
1242 pop_object();
1243 break;
1244 }
1245 case Bytecodes::_if_icmpeq:
1246 case Bytecodes::_if_icmpge:
1247 case Bytecodes::_if_icmpgt:
1248 case Bytecodes::_if_icmple:
1249 case Bytecodes::_if_icmplt:
1250 case Bytecodes::_if_icmpne:
1251 {
1252 pop_int();
1253 pop_int();
1254 break;
1255 }
1256 case Bytecodes::_ifeq:
1257 case Bytecodes::_ifle:
1258 case Bytecodes::_iflt:
1259 case Bytecodes::_ifge:
1260 case Bytecodes::_ifgt:
1261 case Bytecodes::_ifne:
1262 case Bytecodes::_ireturn:
1263 case Bytecodes::_lookupswitch:
1264 case Bytecodes::_tableswitch:
1265 {
1266 pop_int();
1267 break;
1268 }
1269 case Bytecodes::_iinc:
1270 {
1271 check_int(local(str->get_index()));
1272 break;
1273 }
1274 case Bytecodes::_iload: load_local_int(str->get_index()); break;
1275 case Bytecodes::_iload_0: load_local_int(0); break;
1276 case Bytecodes::_iload_1: load_local_int(1); break;
1277 case Bytecodes::_iload_2: load_local_int(2); break;
1278 case Bytecodes::_iload_3: load_local_int(3); break;
1280 case Bytecodes::_instanceof:
1281 {
1282 // Check for uncommon trap:
1283 do_checkcast(str);
1284 pop_object();
1285 push_int();
1286 break;
1287 }
1288 case Bytecodes::_invokeinterface: do_invoke(str, true); break;
1289 case Bytecodes::_invokespecial: do_invoke(str, true); break;
1290 case Bytecodes::_invokestatic: do_invoke(str, false); break;
1292 case Bytecodes::_invokevirtual: do_invoke(str, true); break;
1294 case Bytecodes::_istore: store_local_int(str->get_index()); break;
1295 case Bytecodes::_istore_0: store_local_int(0); break;
1296 case Bytecodes::_istore_1: store_local_int(1); break;
1297 case Bytecodes::_istore_2: store_local_int(2); break;
1298 case Bytecodes::_istore_3: store_local_int(3); break;
1300 case Bytecodes::_jsr:
1301 case Bytecodes::_jsr_w: do_jsr(str); break;
1303 case Bytecodes::_l2d:
1304 {
1305 pop_long();
1306 push_double();
1307 break;
1308 }
1309 case Bytecodes::_l2f:
1310 {
1311 pop_long();
1312 push_float();
1313 break;
1314 }
1315 case Bytecodes::_l2i:
1316 {
1317 pop_long();
1318 push_int();
1319 break;
1320 }
1321 case Bytecodes::_ladd:
1322 case Bytecodes::_land:
1323 case Bytecodes::_ldiv:
1324 case Bytecodes::_lmul:
1325 case Bytecodes::_lor:
1326 case Bytecodes::_lrem:
1327 case Bytecodes::_lsub:
1328 case Bytecodes::_lxor:
1329 {
1330 pop_long();
1331 pop_long();
1332 push_long();
1333 break;
1334 }
1335 case Bytecodes::_laload:
1336 {
1337 pop_int();
1338 ciTypeArrayKlass* array_klass = pop_typeArray();
1339 // Put assert here for right type?
1340 push_long();
1341 break;
1342 }
1343 case Bytecodes::_lastore:
1344 {
1345 pop_long();
1346 pop_int();
1347 pop_typeArray();
1348 // assert here?
1349 break;
1350 }
1351 case Bytecodes::_lcmp:
1352 {
1353 pop_long();
1354 pop_long();
1355 push_int();
1356 break;
1357 }
1358 case Bytecodes::_lconst_0:
1359 case Bytecodes::_lconst_1:
1360 {
1361 push_long();
1362 break;
1363 }
1364 case Bytecodes::_ldc:
1365 case Bytecodes::_ldc_w:
1366 case Bytecodes::_ldc2_w:
1367 {
1368 do_ldc(str);
1369 break;
1370 }
1372 case Bytecodes::_lload: load_local_long(str->get_index()); break;
1373 case Bytecodes::_lload_0: load_local_long(0); break;
1374 case Bytecodes::_lload_1: load_local_long(1); break;
1375 case Bytecodes::_lload_2: load_local_long(2); break;
1376 case Bytecodes::_lload_3: load_local_long(3); break;
1378 case Bytecodes::_lneg:
1379 {
1380 pop_long();
1381 push_long();
1382 break;
1383 }
1384 case Bytecodes::_lreturn:
1385 {
1386 pop_long();
1387 break;
1388 }
1389 case Bytecodes::_lshl:
1390 case Bytecodes::_lshr:
1391 case Bytecodes::_lushr:
1392 {
1393 pop_int();
1394 pop_long();
1395 push_long();
1396 break;
1397 }
1398 case Bytecodes::_lstore: store_local_long(str->get_index()); break;
1399 case Bytecodes::_lstore_0: store_local_long(0); break;
1400 case Bytecodes::_lstore_1: store_local_long(1); break;
1401 case Bytecodes::_lstore_2: store_local_long(2); break;
1402 case Bytecodes::_lstore_3: store_local_long(3); break;
1404 case Bytecodes::_multianewarray: do_multianewarray(str); break;
1406 case Bytecodes::_new: do_new(str); break;
1408 case Bytecodes::_newarray: do_newarray(str); break;
1410 case Bytecodes::_pop:
1411 {
1412 pop();
1413 break;
1414 }
1415 case Bytecodes::_pop2:
1416 {
1417 pop();
1418 pop();
1419 break;
1420 }
1422 case Bytecodes::_putfield: do_putfield(str); break;
1423 case Bytecodes::_putstatic: do_putstatic(str); break;
1425 case Bytecodes::_ret: do_ret(str); break;
1427 case Bytecodes::_swap:
1428 {
1429 ciType* value1 = pop_value();
1430 ciType* value2 = pop_value();
1431 push(value1);
1432 push(value2);
1433 break;
1434 }
1435 case Bytecodes::_wide:
1436 default:
1437 {
1438 // The iterator should skip this.
1439 ShouldNotReachHere();
1440 break;
1441 }
1442 }
1444 if (CITraceTypeFlow) {
1445 print_on(tty);
1446 }
1448 return (_trap_bci != -1);
1449 }
1451 #ifndef PRODUCT
1452 // ------------------------------------------------------------------
1453 // ciTypeFlow::StateVector::print_cell_on
1454 void ciTypeFlow::StateVector::print_cell_on(outputStream* st, Cell c) const {
1455 ciType* type = type_at(c);
1456 if (type == top_type()) {
1457 st->print("top");
1458 } else if (type == bottom_type()) {
1459 st->print("bottom");
1460 } else if (type == null_type()) {
1461 st->print("null");
1462 } else if (type == long2_type()) {
1463 st->print("long2");
1464 } else if (type == double2_type()) {
1465 st->print("double2");
1466 } else if (is_int(type)) {
1467 st->print("int");
1468 } else if (is_long(type)) {
1469 st->print("long");
1470 } else if (is_float(type)) {
1471 st->print("float");
1472 } else if (is_double(type)) {
1473 st->print("double");
1474 } else if (type->is_return_address()) {
1475 st->print("address(%d)", type->as_return_address()->bci());
1476 } else {
1477 if (type->is_klass()) {
1478 type->as_klass()->name()->print_symbol_on(st);
1479 } else {
1480 st->print("UNEXPECTED TYPE");
1481 type->print();
1482 }
1483 }
1484 }
1486 // ------------------------------------------------------------------
1487 // ciTypeFlow::StateVector::print_on
1488 void ciTypeFlow::StateVector::print_on(outputStream* st) const {
1489 int num_locals = _outer->max_locals();
1490 int num_stack = stack_size();
1491 int num_monitors = monitor_count();
1492 st->print_cr(" State : locals %d, stack %d, monitors %d", num_locals, num_stack, num_monitors);
1493 if (num_stack >= 0) {
1494 int i;
1495 for (i = 0; i < num_locals; i++) {
1496 st->print(" local %2d : ", i);
1497 print_cell_on(st, local(i));
1498 st->cr();
1499 }
1500 for (i = 0; i < num_stack; i++) {
1501 st->print(" stack %2d : ", i);
1502 print_cell_on(st, stack(i));
1503 st->cr();
1504 }
1505 }
1506 }
1507 #endif
1509 // ciTypeFlow::Block
1510 //
1511 // A basic block.
1513 // ------------------------------------------------------------------
1514 // ciTypeFlow::Block::Block
1515 ciTypeFlow::Block::Block(ciTypeFlow* outer,
1516 ciBlock *ciblk,
1517 ciTypeFlow::JsrSet* jsrs) {
1518 _ciblock = ciblk;
1519 _exceptions = NULL;
1520 _exc_klasses = NULL;
1521 _successors = NULL;
1522 _state = new (outer->arena()) StateVector(outer);
1523 JsrSet* new_jsrs =
1524 new (outer->arena()) JsrSet(outer->arena(), jsrs->size());
1525 jsrs->copy_into(new_jsrs);
1526 _jsrs = new_jsrs;
1527 _next = NULL;
1528 _on_work_list = false;
1529 _pre_order = -1; assert(!has_pre_order(), "");
1530 _private_copy = false;
1531 _trap_bci = -1;
1532 _trap_index = 0;
1534 if (CITraceTypeFlow) {
1535 tty->print_cr(">> Created new block");
1536 print_on(tty);
1537 }
1539 assert(this->outer() == outer, "outer link set up");
1540 assert(!outer->have_block_count(), "must not have mapped blocks yet");
1541 }
1543 // ------------------------------------------------------------------
1544 // ciTypeFlow::Block::clone_loop_head
1545 //
1546 ciTypeFlow::Block*
1547 ciTypeFlow::Block::clone_loop_head(ciTypeFlow* analyzer,
1548 int branch_bci,
1549 ciTypeFlow::Block* target,
1550 ciTypeFlow::JsrSet* jsrs) {
1551 // Loop optimizations are not performed on Tier1 compiles. Do nothing.
1552 if (analyzer->env()->comp_level() < CompLevel_full_optimization) {
1553 return target;
1554 }
1556 // The current block ends with a branch.
1557 //
1558 // If the target block appears to be the test-clause of a for loop, and
1559 // it is not too large, and it has not yet been cloned, clone it.
1560 // The pre-existing copy becomes the private clone used only by
1561 // the initial iteration of the loop. (We know we are simulating
1562 // the initial iteration right now, since we have never calculated
1563 // successors before for this block.)
1565 if (branch_bci <= start()
1566 && (target->limit() - target->start()) <= CICloneLoopTestLimit
1567 && target->private_copy_count() == 0) {
1568 // Setting the private_copy bit ensures that the target block cannot be
1569 // reached by any other paths, such as fall-in from the loop body.
1570 // The private copy will be accessible only on successor lists
1571 // created up to this point.
1572 target->set_private_copy(true);
1573 if (CITraceTypeFlow) {
1574 tty->print(">> Cloning a test-clause block ");
1575 print_value_on(tty);
1576 tty->cr();
1577 }
1578 // If the target is the current block, then later on a new copy of the
1579 // target block will be created when its bytecodes are reached by
1580 // an alternate path. (This is the case for loops with the loop
1581 // head at the bci-wise bottom of the loop, as with pre-1.4.2 javac.)
1582 //
1583 // Otherwise, duplicate the target block now and use it immediately.
1584 // (The case for loops with the loop head at the bci-wise top of the
1585 // loop, as with 1.4.2 javac.)
1586 //
1587 // In either case, the new copy of the block will remain public.
1588 if (target != this) {
1589 target = analyzer->block_at(branch_bci, jsrs);
1590 }
1591 }
1592 return target;
1593 }
1595 // ------------------------------------------------------------------
1596 // ciTypeFlow::Block::successors
1597 //
1598 // Get the successors for this Block.
1599 GrowableArray<ciTypeFlow::Block*>*
1600 ciTypeFlow::Block::successors(ciBytecodeStream* str,
1601 ciTypeFlow::StateVector* state,
1602 ciTypeFlow::JsrSet* jsrs) {
1603 if (_successors == NULL) {
1604 if (CITraceTypeFlow) {
1605 tty->print(">> Computing successors for block ");
1606 print_value_on(tty);
1607 tty->cr();
1608 }
1610 ciTypeFlow* analyzer = outer();
1611 Arena* arena = analyzer->arena();
1612 Block* block = NULL;
1613 bool has_successor = !has_trap() &&
1614 (control() != ciBlock::fall_through_bci || limit() < analyzer->code_size());
1615 if (!has_successor) {
1616 _successors =
1617 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1618 // No successors
1619 } else if (control() == ciBlock::fall_through_bci) {
1620 assert(str->cur_bci() == limit(), "bad block end");
1621 // This block simply falls through to the next.
1622 _successors =
1623 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1625 Block* block = analyzer->block_at(limit(), _jsrs);
1626 assert(_successors->length() == FALL_THROUGH, "");
1627 _successors->append(block);
1628 } else {
1629 int current_bci = str->cur_bci();
1630 int next_bci = str->next_bci();
1631 int branch_bci = -1;
1632 Block* target = NULL;
1633 assert(str->next_bci() == limit(), "bad block end");
1634 // This block is not a simple fall-though. Interpret
1635 // the current bytecode to find our successors.
1636 switch (str->cur_bc()) {
1637 case Bytecodes::_ifeq: case Bytecodes::_ifne:
1638 case Bytecodes::_iflt: case Bytecodes::_ifge:
1639 case Bytecodes::_ifgt: case Bytecodes::_ifle:
1640 case Bytecodes::_if_icmpeq: case Bytecodes::_if_icmpne:
1641 case Bytecodes::_if_icmplt: case Bytecodes::_if_icmpge:
1642 case Bytecodes::_if_icmpgt: case Bytecodes::_if_icmple:
1643 case Bytecodes::_if_acmpeq: case Bytecodes::_if_acmpne:
1644 case Bytecodes::_ifnull: case Bytecodes::_ifnonnull:
1645 // Our successors are the branch target and the next bci.
1646 branch_bci = str->get_dest();
1647 clone_loop_head(analyzer, branch_bci, this, jsrs);
1648 _successors =
1649 new (arena) GrowableArray<Block*>(arena, 2, 0, NULL);
1650 assert(_successors->length() == IF_NOT_TAKEN, "");
1651 _successors->append(analyzer->block_at(next_bci, jsrs));
1652 assert(_successors->length() == IF_TAKEN, "");
1653 _successors->append(analyzer->block_at(branch_bci, jsrs));
1654 break;
1656 case Bytecodes::_goto:
1657 branch_bci = str->get_dest();
1658 _successors =
1659 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1660 assert(_successors->length() == GOTO_TARGET, "");
1661 target = analyzer->block_at(branch_bci, jsrs);
1662 // If the target block has not been visited yet, and looks like
1663 // a two-way branch, attempt to clone it if it is a loop head.
1664 if (target->_successors != NULL
1665 && target->_successors->length() == (IF_TAKEN + 1)) {
1666 target = clone_loop_head(analyzer, branch_bci, target, jsrs);
1667 }
1668 _successors->append(target);
1669 break;
1671 case Bytecodes::_jsr:
1672 branch_bci = str->get_dest();
1673 _successors =
1674 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1675 assert(_successors->length() == GOTO_TARGET, "");
1676 _successors->append(analyzer->block_at(branch_bci, jsrs));
1677 break;
1679 case Bytecodes::_goto_w:
1680 case Bytecodes::_jsr_w:
1681 _successors =
1682 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1683 assert(_successors->length() == GOTO_TARGET, "");
1684 _successors->append(analyzer->block_at(str->get_far_dest(), jsrs));
1685 break;
1687 case Bytecodes::_tableswitch: {
1688 Bytecode_tableswitch *tableswitch =
1689 Bytecode_tableswitch_at(str->cur_bcp());
1691 int len = tableswitch->length();
1692 _successors =
1693 new (arena) GrowableArray<Block*>(arena, len+1, 0, NULL);
1694 int bci = current_bci + tableswitch->default_offset();
1695 Block* block = analyzer->block_at(bci, jsrs);
1696 assert(_successors->length() == SWITCH_DEFAULT, "");
1697 _successors->append(block);
1698 while (--len >= 0) {
1699 int bci = current_bci + tableswitch->dest_offset_at(len);
1700 block = analyzer->block_at(bci, jsrs);
1701 assert(_successors->length() >= SWITCH_CASES, "");
1702 _successors->append_if_missing(block);
1703 }
1704 break;
1705 }
1707 case Bytecodes::_lookupswitch: {
1708 Bytecode_lookupswitch *lookupswitch =
1709 Bytecode_lookupswitch_at(str->cur_bcp());
1711 int npairs = lookupswitch->number_of_pairs();
1712 _successors =
1713 new (arena) GrowableArray<Block*>(arena, npairs+1, 0, NULL);
1714 int bci = current_bci + lookupswitch->default_offset();
1715 Block* block = analyzer->block_at(bci, jsrs);
1716 assert(_successors->length() == SWITCH_DEFAULT, "");
1717 _successors->append(block);
1718 while(--npairs >= 0) {
1719 LookupswitchPair *pair = lookupswitch->pair_at(npairs);
1720 int bci = current_bci + pair->offset();
1721 Block* block = analyzer->block_at(bci, jsrs);
1722 assert(_successors->length() >= SWITCH_CASES, "");
1723 _successors->append_if_missing(block);
1724 }
1725 break;
1726 }
1728 case Bytecodes::_athrow: case Bytecodes::_ireturn:
1729 case Bytecodes::_lreturn: case Bytecodes::_freturn:
1730 case Bytecodes::_dreturn: case Bytecodes::_areturn:
1731 case Bytecodes::_return:
1732 _successors =
1733 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1734 // No successors
1735 break;
1737 case Bytecodes::_ret: {
1738 _successors =
1739 new (arena) GrowableArray<Block*>(arena, 1, 0, NULL);
1741 Cell local = state->local(str->get_index());
1742 ciType* return_address = state->type_at(local);
1743 assert(return_address->is_return_address(), "verify: wrong type");
1744 int bci = return_address->as_return_address()->bci();
1745 assert(_successors->length() == GOTO_TARGET, "");
1746 _successors->append(analyzer->block_at(bci, jsrs));
1747 break;
1748 }
1750 case Bytecodes::_wide:
1751 default:
1752 ShouldNotReachHere();
1753 break;
1754 }
1755 }
1756 }
1757 return _successors;
1758 }
1760 // ------------------------------------------------------------------
1761 // ciTypeFlow::Block:compute_exceptions
1762 //
1763 // Compute the exceptional successors and types for this Block.
1764 void ciTypeFlow::Block::compute_exceptions() {
1765 assert(_exceptions == NULL && _exc_klasses == NULL, "repeat");
1767 if (CITraceTypeFlow) {
1768 tty->print(">> Computing exceptions for block ");
1769 print_value_on(tty);
1770 tty->cr();
1771 }
1773 ciTypeFlow* analyzer = outer();
1774 Arena* arena = analyzer->arena();
1776 // Any bci in the block will do.
1777 ciExceptionHandlerStream str(analyzer->method(), start());
1779 // Allocate our growable arrays.
1780 int exc_count = str.count();
1781 _exceptions = new (arena) GrowableArray<Block*>(arena, exc_count, 0, NULL);
1782 _exc_klasses = new (arena) GrowableArray<ciInstanceKlass*>(arena, exc_count,
1783 0, NULL);
1785 for ( ; !str.is_done(); str.next()) {
1786 ciExceptionHandler* handler = str.handler();
1787 int bci = handler->handler_bci();
1788 ciInstanceKlass* klass = NULL;
1789 if (bci == -1) {
1790 // There is no catch all. It is possible to exit the method.
1791 break;
1792 }
1793 if (handler->is_catch_all()) {
1794 klass = analyzer->env()->Throwable_klass();
1795 } else {
1796 klass = handler->catch_klass();
1797 }
1798 _exceptions->append(analyzer->block_at(bci, _jsrs));
1799 _exc_klasses->append(klass);
1800 }
1801 }
1803 // ------------------------------------------------------------------
1804 // ciTypeFlow::Block::is_simpler_than
1805 //
1806 // A relation used to order our work list. We work on a block earlier
1807 // if it has a smaller jsr stack or it occurs earlier in the program
1808 // text.
1809 //
1810 // Note: maybe we should redo this functionality to make blocks
1811 // which correspond to exceptions lower priority.
1812 bool ciTypeFlow::Block::is_simpler_than(ciTypeFlow::Block* other) {
1813 if (other == NULL) {
1814 return true;
1815 } else {
1816 int size1 = _jsrs->size();
1817 int size2 = other->_jsrs->size();
1818 if (size1 < size2) {
1819 return true;
1820 } else if (size2 < size1) {
1821 return false;
1822 } else {
1823 #if 0
1824 if (size1 > 0) {
1825 int r1 = _jsrs->record_at(0)->return_address();
1826 int r2 = _jsrs->record_at(0)->return_address();
1827 if (r1 < r2) {
1828 return true;
1829 } else if (r2 < r1) {
1830 return false;
1831 } else {
1832 int e1 = _jsrs->record_at(0)->return_address();
1833 int e2 = _jsrs->record_at(0)->return_address();
1834 if (e1 < e2) {
1835 return true;
1836 } else if (e2 < e1) {
1837 return false;
1838 }
1839 }
1840 }
1841 #endif
1842 return (start() <= other->start());
1843 }
1844 }
1845 }
1847 // ------------------------------------------------------------------
1848 // ciTypeFlow::Block::set_private_copy
1849 // Use this only to make a pre-existing public block into a private copy.
1850 void ciTypeFlow::Block::set_private_copy(bool z) {
1851 assert(z || (z == is_private_copy()), "cannot make a private copy public");
1852 _private_copy = z;
1853 }
1855 #ifndef PRODUCT
1856 // ------------------------------------------------------------------
1857 // ciTypeFlow::Block::print_value_on
1858 void ciTypeFlow::Block::print_value_on(outputStream* st) const {
1859 if (has_pre_order()) st->print("#%-2d ", pre_order());
1860 st->print("[%d - %d)", start(), limit());
1861 if (_jsrs->size() > 0) { st->print("/"); _jsrs->print_on(st); }
1862 if (is_private_copy()) st->print("/private_copy");
1863 }
1865 // ------------------------------------------------------------------
1866 // ciTypeFlow::Block::print_on
1867 void ciTypeFlow::Block::print_on(outputStream* st) const {
1868 if ((Verbose || WizardMode)) {
1869 outer()->method()->print_codes_on(start(), limit(), st);
1870 }
1871 st->print_cr(" ==================================================== ");
1872 st->print (" ");
1873 print_value_on(st);
1874 st->cr();
1875 _state->print_on(st);
1876 if (_successors == NULL) {
1877 st->print_cr(" No successor information");
1878 } else {
1879 int num_successors = _successors->length();
1880 st->print_cr(" Successors : %d", num_successors);
1881 for (int i = 0; i < num_successors; i++) {
1882 Block* successor = _successors->at(i);
1883 st->print(" ");
1884 successor->print_value_on(st);
1885 st->cr();
1886 }
1887 }
1888 if (_exceptions == NULL) {
1889 st->print_cr(" No exception information");
1890 } else {
1891 int num_exceptions = _exceptions->length();
1892 st->print_cr(" Exceptions : %d", num_exceptions);
1893 for (int i = 0; i < num_exceptions; i++) {
1894 Block* exc_succ = _exceptions->at(i);
1895 ciInstanceKlass* exc_klass = _exc_klasses->at(i);
1896 st->print(" ");
1897 exc_succ->print_value_on(st);
1898 st->print(" -- ");
1899 exc_klass->name()->print_symbol_on(st);
1900 st->cr();
1901 }
1902 }
1903 if (has_trap()) {
1904 st->print_cr(" Traps on %d with trap index %d", trap_bci(), trap_index());
1905 }
1906 st->print_cr(" ==================================================== ");
1907 }
1908 #endif
1910 // ciTypeFlow
1911 //
1912 // This is a pass over the bytecodes which computes the following:
1913 // basic block structure
1914 // interpreter type-states (a la the verifier)
1916 // ------------------------------------------------------------------
1917 // ciTypeFlow::ciTypeFlow
1918 ciTypeFlow::ciTypeFlow(ciEnv* env, ciMethod* method, int osr_bci) {
1919 _env = env;
1920 _method = method;
1921 _methodBlocks = method->get_method_blocks();
1922 _max_locals = method->max_locals();
1923 _max_stack = method->max_stack();
1924 _code_size = method->code_size();
1925 _osr_bci = osr_bci;
1926 _failure_reason = NULL;
1927 assert(start_bci() >= 0 && start_bci() < code_size() , "correct osr_bci argument");
1929 _work_list = NULL;
1930 _next_pre_order = 0;
1932 _ciblock_count = _methodBlocks->num_blocks();
1933 _idx_to_blocklist = NEW_ARENA_ARRAY(arena(), GrowableArray<Block*>*, _ciblock_count);
1934 for (int i = 0; i < _ciblock_count; i++) {
1935 _idx_to_blocklist[i] = NULL;
1936 }
1937 _block_map = NULL; // until all blocks are seen
1938 _jsr_count = 0;
1939 _jsr_records = NULL;
1940 }
1942 // ------------------------------------------------------------------
1943 // ciTypeFlow::work_list_next
1944 //
1945 // Get the next basic block from our work list.
1946 ciTypeFlow::Block* ciTypeFlow::work_list_next() {
1947 assert(!work_list_empty(), "work list must not be empty");
1948 Block* next_block = _work_list;
1949 _work_list = next_block->next();
1950 next_block->set_next(NULL);
1951 next_block->set_on_work_list(false);
1952 if (!next_block->has_pre_order()) {
1953 // Assign "pre_order" as each new block is taken from the work list.
1954 // This number may be used by following phases to order block visits.
1955 assert(!have_block_count(), "must not have mapped blocks yet")
1956 next_block->set_pre_order(_next_pre_order++);
1957 }
1958 return next_block;
1959 }
1961 // ------------------------------------------------------------------
1962 // ciTypeFlow::add_to_work_list
1963 //
1964 // Add a basic block to our work list.
1965 void ciTypeFlow::add_to_work_list(ciTypeFlow::Block* block) {
1966 assert(!block->is_on_work_list(), "must not already be on work list");
1968 if (CITraceTypeFlow) {
1969 tty->print(">> Adding block%s ", block->has_pre_order() ? " (again)" : "");
1970 block->print_value_on(tty);
1971 tty->print_cr(" to the work list : ");
1972 }
1974 block->set_on_work_list(true);
1975 if (block->is_simpler_than(_work_list)) {
1976 block->set_next(_work_list);
1977 _work_list = block;
1978 } else {
1979 Block *temp = _work_list;
1980 while (!block->is_simpler_than(temp->next())) {
1981 if (CITraceTypeFlow) {
1982 tty->print(".");
1983 }
1984 temp = temp->next();
1985 }
1986 block->set_next(temp->next());
1987 temp->set_next(block);
1988 }
1989 if (CITraceTypeFlow) {
1990 tty->cr();
1991 }
1992 }
1994 // ------------------------------------------------------------------
1995 // ciTypeFlow::block_at
1996 //
1997 // Return the block beginning at bci which has a JsrSet compatible
1998 // with jsrs.
1999 ciTypeFlow::Block* ciTypeFlow::block_at(int bci, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
2000 // First find the right ciBlock.
2001 if (CITraceTypeFlow) {
2002 tty->print(">> Requesting block for %d/", bci);
2003 jsrs->print_on(tty);
2004 tty->cr();
2005 }
2007 ciBlock* ciblk = _methodBlocks->block_containing(bci);
2008 assert(ciblk->start_bci() == bci, "bad ciBlock boundaries");
2009 Block* block = get_block_for(ciblk->index(), jsrs, option);
2011 assert(block == NULL? (option == no_create): block->is_private_copy() == (option == create_private_copy), "create option consistent with result");
2013 if (CITraceTypeFlow) {
2014 if (block != NULL) {
2015 tty->print(">> Found block ");
2016 block->print_value_on(tty);
2017 tty->cr();
2018 } else {
2019 tty->print_cr(">> No such block.");
2020 }
2021 }
2023 return block;
2024 }
2026 // ------------------------------------------------------------------
2027 // ciTypeFlow::make_jsr_record
2028 //
2029 // Make a JsrRecord for a given (entry, return) pair, if such a record
2030 // does not already exist.
2031 ciTypeFlow::JsrRecord* ciTypeFlow::make_jsr_record(int entry_address,
2032 int return_address) {
2033 if (_jsr_records == NULL) {
2034 _jsr_records = new (arena()) GrowableArray<JsrRecord*>(arena(),
2035 _jsr_count,
2036 0,
2037 NULL);
2038 }
2039 JsrRecord* record = NULL;
2040 int len = _jsr_records->length();
2041 for (int i = 0; i < len; i++) {
2042 JsrRecord* record = _jsr_records->at(i);
2043 if (record->entry_address() == entry_address &&
2044 record->return_address() == return_address) {
2045 return record;
2046 }
2047 }
2049 record = new (arena()) JsrRecord(entry_address, return_address);
2050 _jsr_records->append(record);
2051 return record;
2052 }
2054 // ------------------------------------------------------------------
2055 // ciTypeFlow::flow_exceptions
2056 //
2057 // Merge the current state into all exceptional successors at the
2058 // current point in the code.
2059 void ciTypeFlow::flow_exceptions(GrowableArray<ciTypeFlow::Block*>* exceptions,
2060 GrowableArray<ciInstanceKlass*>* exc_klasses,
2061 ciTypeFlow::StateVector* state) {
2062 int len = exceptions->length();
2063 assert(exc_klasses->length() == len, "must have same length");
2064 for (int i = 0; i < len; i++) {
2065 Block* block = exceptions->at(i);
2066 ciInstanceKlass* exception_klass = exc_klasses->at(i);
2068 if (!exception_klass->is_loaded()) {
2069 // Do not compile any code for unloaded exception types.
2070 // Following compiler passes are responsible for doing this also.
2071 continue;
2072 }
2074 if (block->meet_exception(exception_klass, state)) {
2075 // Block was modified. Add it to the work list.
2076 if (!block->is_on_work_list()) {
2077 add_to_work_list(block);
2078 }
2079 }
2080 }
2081 }
2083 // ------------------------------------------------------------------
2084 // ciTypeFlow::flow_successors
2085 //
2086 // Merge the current state into all successors at the current point
2087 // in the code.
2088 void ciTypeFlow::flow_successors(GrowableArray<ciTypeFlow::Block*>* successors,
2089 ciTypeFlow::StateVector* state) {
2090 int len = successors->length();
2091 for (int i = 0; i < len; i++) {
2092 Block* block = successors->at(i);
2093 if (block->meet(state)) {
2094 // Block was modified. Add it to the work list.
2095 if (!block->is_on_work_list()) {
2096 add_to_work_list(block);
2097 }
2098 }
2099 }
2100 }
2102 // ------------------------------------------------------------------
2103 // ciTypeFlow::can_trap
2104 //
2105 // Tells if a given instruction is able to generate an exception edge.
2106 bool ciTypeFlow::can_trap(ciBytecodeStream& str) {
2107 // Cf. GenerateOopMap::do_exception_edge.
2108 if (!Bytecodes::can_trap(str.cur_bc())) return false;
2110 switch (str.cur_bc()) {
2111 case Bytecodes::_ldc:
2112 case Bytecodes::_ldc_w:
2113 case Bytecodes::_ldc2_w:
2114 case Bytecodes::_aload_0:
2115 // These bytecodes can trap for rewriting. We need to assume that
2116 // they do not throw exceptions to make the monitor analysis work.
2117 return false;
2119 case Bytecodes::_ireturn:
2120 case Bytecodes::_lreturn:
2121 case Bytecodes::_freturn:
2122 case Bytecodes::_dreturn:
2123 case Bytecodes::_areturn:
2124 case Bytecodes::_return:
2125 // We can assume the monitor stack is empty in this analysis.
2126 return false;
2128 case Bytecodes::_monitorexit:
2129 // We can assume monitors are matched in this analysis.
2130 return false;
2131 }
2133 return true;
2134 }
2137 // ------------------------------------------------------------------
2138 // ciTypeFlow::flow_block
2139 //
2140 // Interpret the effects of the bytecodes on the incoming state
2141 // vector of a basic block. Push the changed state to succeeding
2142 // basic blocks.
2143 void ciTypeFlow::flow_block(ciTypeFlow::Block* block,
2144 ciTypeFlow::StateVector* state,
2145 ciTypeFlow::JsrSet* jsrs) {
2146 if (CITraceTypeFlow) {
2147 tty->print("\n>> ANALYZING BLOCK : ");
2148 tty->cr();
2149 block->print_on(tty);
2150 }
2151 assert(block->has_pre_order(), "pre-order is assigned before 1st flow");
2153 int start = block->start();
2154 int limit = block->limit();
2155 int control = block->control();
2156 if (control != ciBlock::fall_through_bci) {
2157 limit = control;
2158 }
2160 // Grab the state from the current block.
2161 block->copy_state_into(state);
2163 GrowableArray<Block*>* exceptions = block->exceptions();
2164 GrowableArray<ciInstanceKlass*>* exc_klasses = block->exc_klasses();
2165 bool has_exceptions = exceptions->length() > 0;
2167 ciBytecodeStream str(method());
2168 str.reset_to_bci(start);
2169 Bytecodes::Code code;
2170 while ((code = str.next()) != ciBytecodeStream::EOBC() &&
2171 str.cur_bci() < limit) {
2172 // Check for exceptional control flow from this point.
2173 if (has_exceptions && can_trap(str)) {
2174 flow_exceptions(exceptions, exc_klasses, state);
2175 }
2176 // Apply the effects of the current bytecode to our state.
2177 bool res = state->apply_one_bytecode(&str);
2179 // Watch for bailouts.
2180 if (failing()) return;
2182 if (res) {
2184 // We have encountered a trap. Record it in this block.
2185 block->set_trap(state->trap_bci(), state->trap_index());
2187 if (CITraceTypeFlow) {
2188 tty->print_cr(">> Found trap");
2189 block->print_on(tty);
2190 }
2192 // Record (no) successors.
2193 block->successors(&str, state, jsrs);
2195 // Discontinue interpretation of this Block.
2196 return;
2197 }
2198 }
2200 GrowableArray<Block*>* successors = NULL;
2201 if (control != ciBlock::fall_through_bci) {
2202 // Check for exceptional control flow from this point.
2203 if (has_exceptions && can_trap(str)) {
2204 flow_exceptions(exceptions, exc_klasses, state);
2205 }
2207 // Fix the JsrSet to reflect effect of the bytecode.
2208 block->copy_jsrs_into(jsrs);
2209 jsrs->apply_control(this, &str, state);
2211 // Find successor edges based on old state and new JsrSet.
2212 successors = block->successors(&str, state, jsrs);
2214 // Apply the control changes to the state.
2215 state->apply_one_bytecode(&str);
2216 } else {
2217 // Fall through control
2218 successors = block->successors(&str, NULL, NULL);
2219 }
2221 // Pass our state to successors.
2222 flow_successors(successors, state);
2223 }
2225 // ------------------------------------------------------------------
2226 // ciTypeFlow::flow_types
2227 //
2228 // Perform the type flow analysis, creating and cloning Blocks as
2229 // necessary.
2230 void ciTypeFlow::flow_types() {
2231 ResourceMark rm;
2232 StateVector* temp_vector = new StateVector(this);
2233 JsrSet* temp_set = new JsrSet(NULL, 16);
2235 // Create the method entry block.
2236 Block* block = block_at(start_bci(), temp_set);
2237 block->set_pre_order(_next_pre_order++);
2238 assert(block->is_start(), "start block must have order #0");
2240 // Load the initial state into it.
2241 const StateVector* start_state = get_start_state();
2242 if (failing()) return;
2243 block->meet(start_state);
2244 add_to_work_list(block);
2246 // Trickle away.
2247 while (!work_list_empty()) {
2248 Block* block = work_list_next();
2249 flow_block(block, temp_vector, temp_set);
2252 // NodeCountCutoff is the number of nodes at which the parser
2253 // will bail out. Probably if we already have lots of BBs,
2254 // the parser will generate at least twice that many nodes and bail out.
2255 // Therefore, this is a conservatively large limit at which to
2256 // bail out in the pre-parse typeflow pass.
2257 int block_limit = MaxNodeLimit / 2;
2259 if (_next_pre_order >= block_limit) {
2260 // Too many basic blocks. Bail out.
2261 //
2262 // This can happen when try/finally constructs are nested to depth N,
2263 // and there is O(2**N) cloning of jsr bodies. See bug 4697245!
2264 record_failure("too many basic blocks");
2265 return;
2266 }
2268 // Watch for bailouts.
2269 if (failing()) return;
2270 }
2271 }
2273 // ------------------------------------------------------------------
2274 // ciTypeFlow::map_blocks
2275 //
2276 // Create the block map, which indexes blocks in pre_order.
2277 void ciTypeFlow::map_blocks() {
2278 assert(_block_map == NULL, "single initialization");
2279 int pre_order_limit = _next_pre_order;
2280 _block_map = NEW_ARENA_ARRAY(arena(), Block*, pre_order_limit);
2281 assert(pre_order_limit == block_count(), "");
2282 int po;
2283 for (po = 0; po < pre_order_limit; po++) {
2284 debug_only(_block_map[po] = NULL);
2285 }
2286 ciMethodBlocks *mblks = _methodBlocks;
2287 ciBlock* current = NULL;
2288 int limit_bci = code_size();
2289 for (int bci = 0; bci < limit_bci; bci++) {
2290 ciBlock* ciblk = mblks->block_containing(bci);
2291 if (ciblk != NULL && ciblk != current) {
2292 current = ciblk;
2293 int curidx = ciblk->index();
2294 int block_count = (_idx_to_blocklist[curidx] == NULL) ? 0 : _idx_to_blocklist[curidx]->length();
2295 for (int i = 0; i < block_count; i++) {
2296 Block* block = _idx_to_blocklist[curidx]->at(i);
2297 if (!block->has_pre_order()) continue;
2298 int po = block->pre_order();
2299 assert(_block_map[po] == NULL, "unique ref to block");
2300 assert(0 <= po && po < pre_order_limit, "");
2301 _block_map[po] = block;
2302 }
2303 }
2304 }
2305 for (po = 0; po < pre_order_limit; po++) {
2306 assert(_block_map[po] != NULL, "must not drop any blocks");
2307 Block* block = _block_map[po];
2308 // Remove dead blocks from successor lists:
2309 for (int e = 0; e <= 1; e++) {
2310 GrowableArray<Block*>* l = e? block->exceptions(): block->successors();
2311 for (int i = 0; i < l->length(); i++) {
2312 Block* s = l->at(i);
2313 if (!s->has_pre_order()) {
2314 if (CITraceTypeFlow) {
2315 tty->print("Removing dead %s successor of #%d: ", (e? "exceptional": "normal"), block->pre_order());
2316 s->print_value_on(tty);
2317 tty->cr();
2318 }
2319 l->remove(s);
2320 --i;
2321 }
2322 }
2323 }
2324 }
2325 }
2327 // ------------------------------------------------------------------
2328 // ciTypeFlow::get_block_for
2329 //
2330 // Find a block with this ciBlock which has a compatible JsrSet.
2331 // If no such block exists, create it, unless the option is no_create.
2332 // If the option is create_private_copy, always create a fresh private copy.
2333 ciTypeFlow::Block* ciTypeFlow::get_block_for(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs, CreateOption option) {
2334 Arena* a = arena();
2335 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
2336 if (blocks == NULL) {
2337 // Query only?
2338 if (option == no_create) return NULL;
2340 // Allocate the growable array.
2341 blocks = new (a) GrowableArray<Block*>(a, 4, 0, NULL);
2342 _idx_to_blocklist[ciBlockIndex] = blocks;
2343 }
2345 if (option != create_private_copy) {
2346 int len = blocks->length();
2347 for (int i = 0; i < len; i++) {
2348 Block* block = blocks->at(i);
2349 if (!block->is_private_copy() && block->is_compatible_with(jsrs)) {
2350 return block;
2351 }
2352 }
2353 }
2355 // Query only?
2356 if (option == no_create) return NULL;
2358 // We did not find a compatible block. Create one.
2359 Block* new_block = new (a) Block(this, _methodBlocks->block(ciBlockIndex), jsrs);
2360 if (option == create_private_copy) new_block->set_private_copy(true);
2361 blocks->append(new_block);
2362 return new_block;
2363 }
2365 // ------------------------------------------------------------------
2366 // ciTypeFlow::private_copy_count
2367 //
2368 int ciTypeFlow::private_copy_count(int ciBlockIndex, ciTypeFlow::JsrSet* jsrs) const {
2369 GrowableArray<Block*>* blocks = _idx_to_blocklist[ciBlockIndex];
2371 if (blocks == NULL) {
2372 return 0;
2373 }
2375 int count = 0;
2376 int len = blocks->length();
2377 for (int i = 0; i < len; i++) {
2378 Block* block = blocks->at(i);
2379 if (block->is_private_copy() && block->is_compatible_with(jsrs)) {
2380 count++;
2381 }
2382 }
2384 return count;
2385 }
2387 // ------------------------------------------------------------------
2388 // ciTypeFlow::do_flow
2389 //
2390 // Perform type inference flow analysis.
2391 void ciTypeFlow::do_flow() {
2392 if (CITraceTypeFlow) {
2393 tty->print_cr("\nPerforming flow analysis on method");
2394 method()->print();
2395 if (is_osr_flow()) tty->print(" at OSR bci %d", start_bci());
2396 tty->cr();
2397 method()->print_codes();
2398 }
2399 if (CITraceTypeFlow) {
2400 tty->print_cr("Initial CI Blocks");
2401 print_on(tty);
2402 }
2403 flow_types();
2404 // Watch for bailouts.
2405 if (failing()) {
2406 return;
2407 }
2408 if (CIPrintTypeFlow || CITraceTypeFlow) {
2409 print_on(tty);
2410 }
2411 map_blocks();
2412 }
2414 // ------------------------------------------------------------------
2415 // ciTypeFlow::record_failure()
2416 // The ciTypeFlow object keeps track of failure reasons separately from the ciEnv.
2417 // This is required because there is not a 1-1 relation between the ciEnv and
2418 // the TypeFlow passes within a compilation task. For example, if the compiler
2419 // is considering inlining a method, it will request a TypeFlow. If that fails,
2420 // the compilation as a whole may continue without the inlining. Some TypeFlow
2421 // requests are not optional; if they fail the requestor is responsible for
2422 // copying the failure reason up to the ciEnv. (See Parse::Parse.)
2423 void ciTypeFlow::record_failure(const char* reason) {
2424 if (env()->log() != NULL) {
2425 env()->log()->elem("failure reason='%s' phase='typeflow'", reason);
2426 }
2427 if (_failure_reason == NULL) {
2428 // Record the first failure reason.
2429 _failure_reason = reason;
2430 }
2431 }
2433 #ifndef PRODUCT
2434 // ------------------------------------------------------------------
2435 // ciTypeFlow::print_on
2436 void ciTypeFlow::print_on(outputStream* st) const {
2437 // Walk through CI blocks
2438 st->print_cr("********************************************************");
2439 st->print ("TypeFlow for ");
2440 method()->name()->print_symbol_on(st);
2441 int limit_bci = code_size();
2442 st->print_cr(" %d bytes", limit_bci);
2443 ciMethodBlocks *mblks = _methodBlocks;
2444 ciBlock* current = NULL;
2445 for (int bci = 0; bci < limit_bci; bci++) {
2446 ciBlock* blk = mblks->block_containing(bci);
2447 if (blk != NULL && blk != current) {
2448 current = blk;
2449 current->print_on(st);
2451 GrowableArray<Block*>* blocks = _idx_to_blocklist[blk->index()];
2452 int num_blocks = (blocks == NULL) ? 0 : blocks->length();
2454 if (num_blocks == 0) {
2455 st->print_cr(" No Blocks");
2456 } else {
2457 for (int i = 0; i < num_blocks; i++) {
2458 Block* block = blocks->at(i);
2459 block->print_on(st);
2460 }
2461 }
2462 st->print_cr("--------------------------------------------------------");
2463 st->cr();
2464 }
2465 }
2466 st->print_cr("********************************************************");
2467 st->cr();
2468 }
2469 #endif
