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src/share/vm/c1/c1_Instruction.cpp@01522ca68fc7
src/share/vm/c1/c1_Instruction.cpp
Tue, 18 Jun 2013 12:31:07 -0700
- author
- johnc
- date
- Tue, 18 Jun 2013 12:31:07 -0700
- changeset 5277
- 01522ca68fc7
- parent 4860
- 46f6f063b272
- child 5914
- d13d7aba8c12
- permissions
- -rw-r--r--
8015237: Parallelize string table scanning during strong root processing
Summary: Parallelize the scanning of the intern string table by having each GC worker claim a given number of buckets. Changes were also reviewed by Per Liden <per.liden@oracle.com>.
Reviewed-by: tschatzl, stefank, twisti
1 /*
2 * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #include "precompiled.hpp"
26 #include "c1/c1_IR.hpp"
27 #include "c1/c1_Instruction.hpp"
28 #include "c1/c1_InstructionPrinter.hpp"
29 #include "c1/c1_ValueStack.hpp"
30 #include "ci/ciObjArrayKlass.hpp"
31 #include "ci/ciTypeArrayKlass.hpp"
34 // Implementation of Instruction
37 int Instruction::dominator_depth() {
38 int result = -1;
39 if (block()) {
40 result = block()->dominator_depth();
41 }
42 assert(result != -1 || this->as_Local(), "Only locals have dominator depth -1");
43 return result;
44 }
46 Instruction::Condition Instruction::mirror(Condition cond) {
47 switch (cond) {
48 case eql: return eql;
49 case neq: return neq;
50 case lss: return gtr;
51 case leq: return geq;
52 case gtr: return lss;
53 case geq: return leq;
54 case aeq: return beq;
55 case beq: return aeq;
56 }
57 ShouldNotReachHere();
58 return eql;
59 }
62 Instruction::Condition Instruction::negate(Condition cond) {
63 switch (cond) {
64 case eql: return neq;
65 case neq: return eql;
66 case lss: return geq;
67 case leq: return gtr;
68 case gtr: return leq;
69 case geq: return lss;
70 case aeq: assert(false, "Above equal cannot be negated");
71 case beq: assert(false, "Below equal cannot be negated");
72 }
73 ShouldNotReachHere();
74 return eql;
75 }
77 void Instruction::update_exception_state(ValueStack* state) {
78 if (state != NULL && (state->kind() == ValueStack::EmptyExceptionState || state->kind() == ValueStack::ExceptionState)) {
79 assert(state->kind() == ValueStack::EmptyExceptionState || Compilation::current()->env()->jvmti_can_access_local_variables(), "unexpected state kind");
80 _exception_state = state;
81 } else {
82 _exception_state = NULL;
83 }
84 }
86 // Prev without need to have BlockBegin
87 Instruction* Instruction::prev() {
88 Instruction* p = NULL;
89 Instruction* q = block();
90 while (q != this) {
91 assert(q != NULL, "this is not in the block's instruction list");
92 p = q; q = q->next();
93 }
94 return p;
95 }
98 void Instruction::state_values_do(ValueVisitor* f) {
99 if (state_before() != NULL) {
100 state_before()->values_do(f);
101 }
102 if (exception_state() != NULL){
103 exception_state()->values_do(f);
104 }
105 }
108 #ifndef PRODUCT
109 void Instruction::check_state(ValueStack* state) {
110 if (state != NULL) {
111 state->verify();
112 }
113 }
116 void Instruction::print() {
117 InstructionPrinter ip;
118 print(ip);
119 }
122 void Instruction::print_line() {
123 InstructionPrinter ip;
124 ip.print_line(this);
125 }
128 void Instruction::print(InstructionPrinter& ip) {
129 ip.print_head();
130 ip.print_line(this);
131 tty->cr();
132 }
133 #endif // PRODUCT
136 // perform constant and interval tests on index value
137 bool AccessIndexed::compute_needs_range_check() {
139 if (length()) {
141 Constant* clength = length()->as_Constant();
142 Constant* cindex = index()->as_Constant();
143 if (clength && cindex) {
144 IntConstant* l = clength->type()->as_IntConstant();
145 IntConstant* i = cindex->type()->as_IntConstant();
146 if (l && i && i->value() < l->value() && i->value() >= 0) {
147 return false;
148 }
149 }
150 }
152 if (!this->check_flag(NeedsRangeCheckFlag)) {
153 return false;
154 }
156 return true;
157 }
160 ciType* Local::exact_type() const {
161 ciType* type = declared_type();
163 // for primitive arrays, the declared type is the exact type
164 if (type->is_type_array_klass()) {
165 return type;
166 } else if (type->is_instance_klass()) {
167 ciInstanceKlass* ik = (ciInstanceKlass*)type;
168 if (ik->is_loaded() && ik->is_final() && !ik->is_interface()) {
169 return type;
170 }
171 } else if (type->is_obj_array_klass()) {
172 ciObjArrayKlass* oak = (ciObjArrayKlass*)type;
173 ciType* base = oak->base_element_type();
174 if (base->is_instance_klass()) {
175 ciInstanceKlass* ik = base->as_instance_klass();
176 if (ik->is_loaded() && ik->is_final()) {
177 return type;
178 }
179 } else if (base->is_primitive_type()) {
180 return type;
181 }
182 }
183 return NULL;
184 }
186 ciType* Constant::exact_type() const {
187 if (type()->is_object()) {
188 return type()->as_ObjectType()->exact_type();
189 }
190 return NULL;
191 }
193 ciType* LoadIndexed::exact_type() const {
194 ciType* array_type = array()->exact_type();
195 if (array_type == NULL) {
196 return NULL;
197 }
198 assert(array_type->is_array_klass(), "what else?");
199 ciArrayKlass* ak = (ciArrayKlass*)array_type;
201 if (ak->element_type()->is_instance_klass()) {
202 ciInstanceKlass* ik = (ciInstanceKlass*)ak->element_type();
203 if (ik->is_loaded() && ik->is_final()) {
204 return ik;
205 }
206 }
207 return NULL;
208 }
211 ciType* LoadIndexed::declared_type() const {
212 ciType* array_type = array()->declared_type();
213 if (array_type == NULL || !array_type->is_loaded()) {
214 return NULL;
215 }
216 assert(array_type->is_array_klass(), "what else?");
217 ciArrayKlass* ak = (ciArrayKlass*)array_type;
218 return ak->element_type();
219 }
222 ciType* LoadField::declared_type() const {
223 return field()->type();
224 }
227 ciType* LoadField::exact_type() const {
228 ciType* type = declared_type();
229 // for primitive arrays, the declared type is the exact type
230 if (type->is_type_array_klass()) {
231 return type;
232 }
233 if (type->is_instance_klass()) {
234 ciInstanceKlass* ik = (ciInstanceKlass*)type;
235 if (ik->is_loaded() && ik->is_final()) {
236 return type;
237 }
238 }
239 return NULL;
240 }
243 ciType* NewTypeArray::exact_type() const {
244 return ciTypeArrayKlass::make(elt_type());
245 }
247 ciType* NewObjectArray::exact_type() const {
248 return ciObjArrayKlass::make(klass());
249 }
251 ciType* NewArray::declared_type() const {
252 return exact_type();
253 }
255 ciType* NewInstance::exact_type() const {
256 return klass();
257 }
259 ciType* NewInstance::declared_type() const {
260 return exact_type();
261 }
263 ciType* CheckCast::declared_type() const {
264 return klass();
265 }
267 ciType* CheckCast::exact_type() const {
268 if (klass()->is_instance_klass()) {
269 ciInstanceKlass* ik = (ciInstanceKlass*)klass();
270 if (ik->is_loaded() && ik->is_final()) {
271 return ik;
272 }
273 }
274 return NULL;
275 }
277 // Implementation of ArithmeticOp
279 bool ArithmeticOp::is_commutative() const {
280 switch (op()) {
281 case Bytecodes::_iadd: // fall through
282 case Bytecodes::_ladd: // fall through
283 case Bytecodes::_fadd: // fall through
284 case Bytecodes::_dadd: // fall through
285 case Bytecodes::_imul: // fall through
286 case Bytecodes::_lmul: // fall through
287 case Bytecodes::_fmul: // fall through
288 case Bytecodes::_dmul: return true;
289 }
290 return false;
291 }
294 bool ArithmeticOp::can_trap() const {
295 switch (op()) {
296 case Bytecodes::_idiv: // fall through
297 case Bytecodes::_ldiv: // fall through
298 case Bytecodes::_irem: // fall through
299 case Bytecodes::_lrem: return true;
300 }
301 return false;
302 }
305 // Implementation of LogicOp
307 bool LogicOp::is_commutative() const {
308 #ifdef ASSERT
309 switch (op()) {
310 case Bytecodes::_iand: // fall through
311 case Bytecodes::_land: // fall through
312 case Bytecodes::_ior : // fall through
313 case Bytecodes::_lor : // fall through
314 case Bytecodes::_ixor: // fall through
315 case Bytecodes::_lxor: break;
316 default : ShouldNotReachHere();
317 }
318 #endif
319 // all LogicOps are commutative
320 return true;
321 }
324 // Implementation of IfOp
326 bool IfOp::is_commutative() const {
327 return cond() == eql || cond() == neq;
328 }
331 // Implementation of StateSplit
333 void StateSplit::substitute(BlockList& list, BlockBegin* old_block, BlockBegin* new_block) {
334 NOT_PRODUCT(bool assigned = false;)
335 for (int i = 0; i < list.length(); i++) {
336 BlockBegin** b = list.adr_at(i);
337 if (*b == old_block) {
338 *b = new_block;
339 NOT_PRODUCT(assigned = true;)
340 }
341 }
342 assert(assigned == true, "should have assigned at least once");
343 }
346 IRScope* StateSplit::scope() const {
347 return _state->scope();
348 }
351 void StateSplit::state_values_do(ValueVisitor* f) {
352 Instruction::state_values_do(f);
353 if (state() != NULL) state()->values_do(f);
354 }
357 void BlockBegin::state_values_do(ValueVisitor* f) {
358 StateSplit::state_values_do(f);
360 if (is_set(BlockBegin::exception_entry_flag)) {
361 for (int i = 0; i < number_of_exception_states(); i++) {
362 exception_state_at(i)->values_do(f);
363 }
364 }
365 }
368 // Implementation of Invoke
371 Invoke::Invoke(Bytecodes::Code code, ValueType* result_type, Value recv, Values* args,
372 int vtable_index, ciMethod* target, ValueStack* state_before)
373 : StateSplit(result_type, state_before)
374 , _code(code)
375 , _recv(recv)
376 , _args(args)
377 , _vtable_index(vtable_index)
378 , _target(target)
379 {
380 set_flag(TargetIsLoadedFlag, target->is_loaded());
381 set_flag(TargetIsFinalFlag, target_is_loaded() && target->is_final_method());
382 set_flag(TargetIsStrictfpFlag, target_is_loaded() && target->is_strict());
384 assert(args != NULL, "args must exist");
385 #ifdef ASSERT
386 AssertValues assert_value;
387 values_do(&assert_value);
388 #endif
390 // provide an initial guess of signature size.
391 _signature = new BasicTypeList(number_of_arguments() + (has_receiver() ? 1 : 0));
392 if (has_receiver()) {
393 _signature->append(as_BasicType(receiver()->type()));
394 }
395 for (int i = 0; i < number_of_arguments(); i++) {
396 ValueType* t = argument_at(i)->type();
397 BasicType bt = as_BasicType(t);
398 _signature->append(bt);
399 }
400 }
403 void Invoke::state_values_do(ValueVisitor* f) {
404 StateSplit::state_values_do(f);
405 if (state_before() != NULL) state_before()->values_do(f);
406 if (state() != NULL) state()->values_do(f);
407 }
409 ciType* Invoke::declared_type() const {
410 ciType *t = _target->signature()->return_type();
411 assert(t->basic_type() != T_VOID, "need return value of void method?");
412 return t;
413 }
415 // Implementation of Contant
416 intx Constant::hash() const {
417 if (state_before() == NULL) {
418 switch (type()->tag()) {
419 case intTag:
420 return HASH2(name(), type()->as_IntConstant()->value());
421 case addressTag:
422 return HASH2(name(), type()->as_AddressConstant()->value());
423 case longTag:
424 {
425 jlong temp = type()->as_LongConstant()->value();
426 return HASH3(name(), high(temp), low(temp));
427 }
428 case floatTag:
429 return HASH2(name(), jint_cast(type()->as_FloatConstant()->value()));
430 case doubleTag:
431 {
432 jlong temp = jlong_cast(type()->as_DoubleConstant()->value());
433 return HASH3(name(), high(temp), low(temp));
434 }
435 case objectTag:
436 assert(type()->as_ObjectType()->is_loaded(), "can't handle unloaded values");
437 return HASH2(name(), type()->as_ObjectType()->constant_value());
438 case metaDataTag:
439 assert(type()->as_MetadataType()->is_loaded(), "can't handle unloaded values");
440 return HASH2(name(), type()->as_MetadataType()->constant_value());
441 default:
442 ShouldNotReachHere();
443 }
444 }
445 return 0;
446 }
448 bool Constant::is_equal(Value v) const {
449 if (v->as_Constant() == NULL) return false;
451 switch (type()->tag()) {
452 case intTag:
453 {
454 IntConstant* t1 = type()->as_IntConstant();
455 IntConstant* t2 = v->type()->as_IntConstant();
456 return (t1 != NULL && t2 != NULL &&
457 t1->value() == t2->value());
458 }
459 case longTag:
460 {
461 LongConstant* t1 = type()->as_LongConstant();
462 LongConstant* t2 = v->type()->as_LongConstant();
463 return (t1 != NULL && t2 != NULL &&
464 t1->value() == t2->value());
465 }
466 case floatTag:
467 {
468 FloatConstant* t1 = type()->as_FloatConstant();
469 FloatConstant* t2 = v->type()->as_FloatConstant();
470 return (t1 != NULL && t2 != NULL &&
471 jint_cast(t1->value()) == jint_cast(t2->value()));
472 }
473 case doubleTag:
474 {
475 DoubleConstant* t1 = type()->as_DoubleConstant();
476 DoubleConstant* t2 = v->type()->as_DoubleConstant();
477 return (t1 != NULL && t2 != NULL &&
478 jlong_cast(t1->value()) == jlong_cast(t2->value()));
479 }
480 case objectTag:
481 {
482 ObjectType* t1 = type()->as_ObjectType();
483 ObjectType* t2 = v->type()->as_ObjectType();
484 return (t1 != NULL && t2 != NULL &&
485 t1->is_loaded() && t2->is_loaded() &&
486 t1->constant_value() == t2->constant_value());
487 }
488 case metaDataTag:
489 {
490 MetadataType* t1 = type()->as_MetadataType();
491 MetadataType* t2 = v->type()->as_MetadataType();
492 return (t1 != NULL && t2 != NULL &&
493 t1->is_loaded() && t2->is_loaded() &&
494 t1->constant_value() == t2->constant_value());
495 }
496 }
497 return false;
498 }
500 Constant::CompareResult Constant::compare(Instruction::Condition cond, Value right) const {
501 Constant* rc = right->as_Constant();
502 // other is not a constant
503 if (rc == NULL) return not_comparable;
505 ValueType* lt = type();
506 ValueType* rt = rc->type();
507 // different types
508 if (lt->base() != rt->base()) return not_comparable;
509 switch (lt->tag()) {
510 case intTag: {
511 int x = lt->as_IntConstant()->value();
512 int y = rt->as_IntConstant()->value();
513 switch (cond) {
514 case If::eql: return x == y ? cond_true : cond_false;
515 case If::neq: return x != y ? cond_true : cond_false;
516 case If::lss: return x < y ? cond_true : cond_false;
517 case If::leq: return x <= y ? cond_true : cond_false;
518 case If::gtr: return x > y ? cond_true : cond_false;
519 case If::geq: return x >= y ? cond_true : cond_false;
520 }
521 break;
522 }
523 case longTag: {
524 jlong x = lt->as_LongConstant()->value();
525 jlong y = rt->as_LongConstant()->value();
526 switch (cond) {
527 case If::eql: return x == y ? cond_true : cond_false;
528 case If::neq: return x != y ? cond_true : cond_false;
529 case If::lss: return x < y ? cond_true : cond_false;
530 case If::leq: return x <= y ? cond_true : cond_false;
531 case If::gtr: return x > y ? cond_true : cond_false;
532 case If::geq: return x >= y ? cond_true : cond_false;
533 }
534 break;
535 }
536 case objectTag: {
537 ciObject* xvalue = lt->as_ObjectType()->constant_value();
538 ciObject* yvalue = rt->as_ObjectType()->constant_value();
539 assert(xvalue != NULL && yvalue != NULL, "not constants");
540 if (xvalue->is_loaded() && yvalue->is_loaded()) {
541 switch (cond) {
542 case If::eql: return xvalue == yvalue ? cond_true : cond_false;
543 case If::neq: return xvalue != yvalue ? cond_true : cond_false;
544 }
545 }
546 break;
547 }
548 case metaDataTag: {
549 ciMetadata* xvalue = lt->as_MetadataType()->constant_value();
550 ciMetadata* yvalue = rt->as_MetadataType()->constant_value();
551 assert(xvalue != NULL && yvalue != NULL, "not constants");
552 if (xvalue->is_loaded() && yvalue->is_loaded()) {
553 switch (cond) {
554 case If::eql: return xvalue == yvalue ? cond_true : cond_false;
555 case If::neq: return xvalue != yvalue ? cond_true : cond_false;
556 }
557 }
558 break;
559 }
560 }
561 return not_comparable;
562 }
565 // Implementation of BlockBegin
567 void BlockBegin::set_end(BlockEnd* end) {
568 assert(end != NULL, "should not reset block end to NULL");
569 if (end == _end) {
570 return;
571 }
572 clear_end();
574 // Set the new end
575 _end = end;
577 _successors.clear();
578 // Now reset successors list based on BlockEnd
579 for (int i = 0; i < end->number_of_sux(); i++) {
580 BlockBegin* sux = end->sux_at(i);
581 _successors.append(sux);
582 sux->_predecessors.append(this);
583 }
584 _end->set_begin(this);
585 }
588 void BlockBegin::clear_end() {
589 // Must make the predecessors/successors match up with the
590 // BlockEnd's notion.
591 if (_end != NULL) {
592 // disconnect from the old end
593 _end->set_begin(NULL);
595 // disconnect this block from it's current successors
596 for (int i = 0; i < _successors.length(); i++) {
597 _successors.at(i)->remove_predecessor(this);
598 }
599 _end = NULL;
600 }
601 }
604 void BlockBegin::disconnect_edge(BlockBegin* from, BlockBegin* to) {
605 // disconnect any edges between from and to
606 #ifndef PRODUCT
607 if (PrintIR && Verbose) {
608 tty->print_cr("Disconnected edge B%d -> B%d", from->block_id(), to->block_id());
609 }
610 #endif
611 for (int s = 0; s < from->number_of_sux();) {
612 BlockBegin* sux = from->sux_at(s);
613 if (sux == to) {
614 int index = sux->_predecessors.index_of(from);
615 if (index >= 0) {
616 sux->_predecessors.remove_at(index);
617 }
618 from->_successors.remove_at(s);
619 } else {
620 s++;
621 }
622 }
623 }
626 void BlockBegin::disconnect_from_graph() {
627 // disconnect this block from all other blocks
628 for (int p = 0; p < number_of_preds(); p++) {
629 pred_at(p)->remove_successor(this);
630 }
631 for (int s = 0; s < number_of_sux(); s++) {
632 sux_at(s)->remove_predecessor(this);
633 }
634 }
636 void BlockBegin::substitute_sux(BlockBegin* old_sux, BlockBegin* new_sux) {
637 // modify predecessors before substituting successors
638 for (int i = 0; i < number_of_sux(); i++) {
639 if (sux_at(i) == old_sux) {
640 // remove old predecessor before adding new predecessor
641 // otherwise there is a dead predecessor in the list
642 new_sux->remove_predecessor(old_sux);
643 new_sux->add_predecessor(this);
644 }
645 }
646 old_sux->remove_predecessor(this);
647 end()->substitute_sux(old_sux, new_sux);
648 }
652 // In general it is not possible to calculate a value for the field "depth_first_number"
653 // of the inserted block, without recomputing the values of the other blocks
654 // in the CFG. Therefore the value of "depth_first_number" in BlockBegin becomes meaningless.
655 BlockBegin* BlockBegin::insert_block_between(BlockBegin* sux) {
656 int bci = sux->bci();
657 // critical edge splitting may introduce a goto after a if and array
658 // bound check elimination may insert a predicate between the if and
659 // goto. The bci of the goto can't be the one of the if otherwise
660 // the state and bci are inconsistent and a deoptimization triggered
661 // by the predicate would lead to incorrect execution/a crash.
662 BlockBegin* new_sux = new BlockBegin(bci);
664 // mark this block (special treatment when block order is computed)
665 new_sux->set(critical_edge_split_flag);
667 // This goto is not a safepoint.
668 Goto* e = new Goto(sux, false);
669 new_sux->set_next(e, bci);
670 new_sux->set_end(e);
671 // setup states
672 ValueStack* s = end()->state();
673 new_sux->set_state(s->copy(s->kind(), bci));
674 e->set_state(s->copy(s->kind(), bci));
675 assert(new_sux->state()->locals_size() == s->locals_size(), "local size mismatch!");
676 assert(new_sux->state()->stack_size() == s->stack_size(), "stack size mismatch!");
677 assert(new_sux->state()->locks_size() == s->locks_size(), "locks size mismatch!");
679 // link predecessor to new block
680 end()->substitute_sux(sux, new_sux);
682 // The ordering needs to be the same, so remove the link that the
683 // set_end call above added and substitute the new_sux for this
684 // block.
685 sux->remove_predecessor(new_sux);
687 // the successor could be the target of a switch so it might have
688 // multiple copies of this predecessor, so substitute the new_sux
689 // for the first and delete the rest.
690 bool assigned = false;
691 BlockList& list = sux->_predecessors;
692 for (int i = 0; i < list.length(); i++) {
693 BlockBegin** b = list.adr_at(i);
694 if (*b == this) {
695 if (assigned) {
696 list.remove_at(i);
697 // reprocess this index
698 i--;
699 } else {
700 assigned = true;
701 *b = new_sux;
702 }
703 // link the new block back to it's predecessors.
704 new_sux->add_predecessor(this);
705 }
706 }
707 assert(assigned == true, "should have assigned at least once");
708 return new_sux;
709 }
712 void BlockBegin::remove_successor(BlockBegin* pred) {
713 int idx;
714 while ((idx = _successors.index_of(pred)) >= 0) {
715 _successors.remove_at(idx);
716 }
717 }
720 void BlockBegin::add_predecessor(BlockBegin* pred) {
721 _predecessors.append(pred);
722 }
725 void BlockBegin::remove_predecessor(BlockBegin* pred) {
726 int idx;
727 while ((idx = _predecessors.index_of(pred)) >= 0) {
728 _predecessors.remove_at(idx);
729 }
730 }
733 void BlockBegin::add_exception_handler(BlockBegin* b) {
734 assert(b != NULL && (b->is_set(exception_entry_flag)), "exception handler must exist");
735 // add only if not in the list already
736 if (!_exception_handlers.contains(b)) _exception_handlers.append(b);
737 }
739 int BlockBegin::add_exception_state(ValueStack* state) {
740 assert(is_set(exception_entry_flag), "only for xhandlers");
741 if (_exception_states == NULL) {
742 _exception_states = new ValueStackStack(4);
743 }
744 _exception_states->append(state);
745 return _exception_states->length() - 1;
746 }
749 void BlockBegin::iterate_preorder(boolArray& mark, BlockClosure* closure) {
750 if (!mark.at(block_id())) {
751 mark.at_put(block_id(), true);
752 closure->block_do(this);
753 BlockEnd* e = end(); // must do this after block_do because block_do may change it!
754 { for (int i = number_of_exception_handlers() - 1; i >= 0; i--) exception_handler_at(i)->iterate_preorder(mark, closure); }
755 { for (int i = e->number_of_sux () - 1; i >= 0; i--) e->sux_at (i)->iterate_preorder(mark, closure); }
756 }
757 }
760 void BlockBegin::iterate_postorder(boolArray& mark, BlockClosure* closure) {
761 if (!mark.at(block_id())) {
762 mark.at_put(block_id(), true);
763 BlockEnd* e = end();
764 { for (int i = number_of_exception_handlers() - 1; i >= 0; i--) exception_handler_at(i)->iterate_postorder(mark, closure); }
765 { for (int i = e->number_of_sux () - 1; i >= 0; i--) e->sux_at (i)->iterate_postorder(mark, closure); }
766 closure->block_do(this);
767 }
768 }
771 void BlockBegin::iterate_preorder(BlockClosure* closure) {
772 boolArray mark(number_of_blocks(), false);
773 iterate_preorder(mark, closure);
774 }
777 void BlockBegin::iterate_postorder(BlockClosure* closure) {
778 boolArray mark(number_of_blocks(), false);
779 iterate_postorder(mark, closure);
780 }
783 void BlockBegin::block_values_do(ValueVisitor* f) {
784 for (Instruction* n = this; n != NULL; n = n->next()) n->values_do(f);
785 }
788 #ifndef PRODUCT
789 #define TRACE_PHI(code) if (PrintPhiFunctions) { code; }
790 #else
791 #define TRACE_PHI(coce)
792 #endif
795 bool BlockBegin::try_merge(ValueStack* new_state) {
796 TRACE_PHI(tty->print_cr("********** try_merge for block B%d", block_id()));
798 // local variables used for state iteration
799 int index;
800 Value new_value, existing_value;
802 ValueStack* existing_state = state();
803 if (existing_state == NULL) {
804 TRACE_PHI(tty->print_cr("first call of try_merge for this block"));
806 if (is_set(BlockBegin::was_visited_flag)) {
807 // this actually happens for complicated jsr/ret structures
808 return false; // BAILOUT in caller
809 }
811 // copy state because it is altered
812 new_state = new_state->copy(ValueStack::BlockBeginState, bci());
814 // Use method liveness to invalidate dead locals
815 MethodLivenessResult liveness = new_state->scope()->method()->liveness_at_bci(bci());
816 if (liveness.is_valid()) {
817 assert((int)liveness.size() == new_state->locals_size(), "error in use of liveness");
819 for_each_local_value(new_state, index, new_value) {
820 if (!liveness.at(index) || new_value->type()->is_illegal()) {
821 new_state->invalidate_local(index);
822 TRACE_PHI(tty->print_cr("invalidating dead local %d", index));
823 }
824 }
825 }
827 if (is_set(BlockBegin::parser_loop_header_flag)) {
828 TRACE_PHI(tty->print_cr("loop header block, initializing phi functions"));
830 for_each_stack_value(new_state, index, new_value) {
831 new_state->setup_phi_for_stack(this, index);
832 TRACE_PHI(tty->print_cr("creating phi-function %c%d for stack %d", new_state->stack_at(index)->type()->tchar(), new_state->stack_at(index)->id(), index));
833 }
835 BitMap requires_phi_function = new_state->scope()->requires_phi_function();
837 for_each_local_value(new_state, index, new_value) {
838 bool requires_phi = requires_phi_function.at(index) || (new_value->type()->is_double_word() && requires_phi_function.at(index + 1));
839 if (requires_phi || !SelectivePhiFunctions) {
840 new_state->setup_phi_for_local(this, index);
841 TRACE_PHI(tty->print_cr("creating phi-function %c%d for local %d", new_state->local_at(index)->type()->tchar(), new_state->local_at(index)->id(), index));
842 }
843 }
844 }
846 // initialize state of block
847 set_state(new_state);
849 } else if (existing_state->is_same(new_state)) {
850 TRACE_PHI(tty->print_cr("exisiting state found"));
852 assert(existing_state->scope() == new_state->scope(), "not matching");
853 assert(existing_state->locals_size() == new_state->locals_size(), "not matching");
854 assert(existing_state->stack_size() == new_state->stack_size(), "not matching");
856 if (is_set(BlockBegin::was_visited_flag)) {
857 TRACE_PHI(tty->print_cr("loop header block, phis must be present"));
859 if (!is_set(BlockBegin::parser_loop_header_flag)) {
860 // this actually happens for complicated jsr/ret structures
861 return false; // BAILOUT in caller
862 }
864 for_each_local_value(existing_state, index, existing_value) {
865 Value new_value = new_state->local_at(index);
866 if (new_value == NULL || new_value->type()->tag() != existing_value->type()->tag()) {
867 // The old code invalidated the phi function here
868 // Because dead locals are replaced with NULL, this is a very rare case now, so simply bail out
869 return false; // BAILOUT in caller
870 }
871 }
873 #ifdef ASSERT
874 // check that all necessary phi functions are present
875 for_each_stack_value(existing_state, index, existing_value) {
876 assert(existing_value->as_Phi() != NULL && existing_value->as_Phi()->block() == this, "phi function required");
877 }
878 for_each_local_value(existing_state, index, existing_value) {
879 assert(existing_value == new_state->local_at(index) || (existing_value->as_Phi() != NULL && existing_value->as_Phi()->as_Phi()->block() == this), "phi function required");
880 }
881 #endif
883 } else {
884 TRACE_PHI(tty->print_cr("creating phi functions on demand"));
886 // create necessary phi functions for stack
887 for_each_stack_value(existing_state, index, existing_value) {
888 Value new_value = new_state->stack_at(index);
889 Phi* existing_phi = existing_value->as_Phi();
891 if (new_value != existing_value && (existing_phi == NULL || existing_phi->block() != this)) {
892 existing_state->setup_phi_for_stack(this, index);
893 TRACE_PHI(tty->print_cr("creating phi-function %c%d for stack %d", existing_state->stack_at(index)->type()->tchar(), existing_state->stack_at(index)->id(), index));
894 }
895 }
897 // create necessary phi functions for locals
898 for_each_local_value(existing_state, index, existing_value) {
899 Value new_value = new_state->local_at(index);
900 Phi* existing_phi = existing_value->as_Phi();
902 if (new_value == NULL || new_value->type()->tag() != existing_value->type()->tag()) {
903 existing_state->invalidate_local(index);
904 TRACE_PHI(tty->print_cr("invalidating local %d because of type mismatch", index));
905 } else if (new_value != existing_value && (existing_phi == NULL || existing_phi->block() != this)) {
906 existing_state->setup_phi_for_local(this, index);
907 TRACE_PHI(tty->print_cr("creating phi-function %c%d for local %d", existing_state->local_at(index)->type()->tchar(), existing_state->local_at(index)->id(), index));
908 }
909 }
910 }
912 assert(existing_state->caller_state() == new_state->caller_state(), "caller states must be equal");
914 } else {
915 assert(false, "stack or locks not matching (invalid bytecodes)");
916 return false;
917 }
919 TRACE_PHI(tty->print_cr("********** try_merge for block B%d successful", block_id()));
921 return true;
922 }
925 #ifndef PRODUCT
926 void BlockBegin::print_block() {
927 InstructionPrinter ip;
928 print_block(ip, false);
929 }
932 void BlockBegin::print_block(InstructionPrinter& ip, bool live_only) {
933 ip.print_instr(this); tty->cr();
934 ip.print_stack(this->state()); tty->cr();
935 ip.print_inline_level(this);
936 ip.print_head();
937 for (Instruction* n = next(); n != NULL; n = n->next()) {
938 if (!live_only || n->is_pinned() || n->use_count() > 0) {
939 ip.print_line(n);
940 }
941 }
942 tty->cr();
943 }
944 #endif // PRODUCT
947 // Implementation of BlockList
949 void BlockList::iterate_forward (BlockClosure* closure) {
950 const int l = length();
951 for (int i = 0; i < l; i++) closure->block_do(at(i));
952 }
955 void BlockList::iterate_backward(BlockClosure* closure) {
956 for (int i = length() - 1; i >= 0; i--) closure->block_do(at(i));
957 }
960 void BlockList::blocks_do(void f(BlockBegin*)) {
961 for (int i = length() - 1; i >= 0; i--) f(at(i));
962 }
965 void BlockList::values_do(ValueVisitor* f) {
966 for (int i = length() - 1; i >= 0; i--) at(i)->block_values_do(f);
967 }
970 #ifndef PRODUCT
971 void BlockList::print(bool cfg_only, bool live_only) {
972 InstructionPrinter ip;
973 for (int i = 0; i < length(); i++) {
974 BlockBegin* block = at(i);
975 if (cfg_only) {
976 ip.print_instr(block); tty->cr();
977 } else {
978 block->print_block(ip, live_only);
979 }
980 }
981 }
982 #endif // PRODUCT
985 // Implementation of BlockEnd
987 void BlockEnd::set_begin(BlockBegin* begin) {
988 BlockList* sux = NULL;
989 if (begin != NULL) {
990 sux = begin->successors();
991 } else if (this->begin() != NULL) {
992 // copy our sux list
993 BlockList* sux = new BlockList(this->begin()->number_of_sux());
994 for (int i = 0; i < this->begin()->number_of_sux(); i++) {
995 sux->append(this->begin()->sux_at(i));
996 }
997 }
998 _sux = sux;
999 }
1002 void BlockEnd::substitute_sux(BlockBegin* old_sux, BlockBegin* new_sux) {
1003 substitute(*_sux, old_sux, new_sux);
1004 }
1007 // Implementation of Phi
1009 // Normal phi functions take their operands from the last instruction of the
1010 // predecessor. Special handling is needed for xhanlder entries because there
1011 // the state of arbitrary instructions are needed.
1013 Value Phi::operand_at(int i) const {
1014 ValueStack* state;
1015 if (_block->is_set(BlockBegin::exception_entry_flag)) {
1016 state = _block->exception_state_at(i);
1017 } else {
1018 state = _block->pred_at(i)->end()->state();
1019 }
1020 assert(state != NULL, "");
1022 if (is_local()) {
1023 return state->local_at(local_index());
1024 } else {
1025 return state->stack_at(stack_index());
1026 }
1027 }
1030 int Phi::operand_count() const {
1031 if (_block->is_set(BlockBegin::exception_entry_flag)) {
1032 return _block->number_of_exception_states();
1033 } else {
1034 return _block->number_of_preds();
1035 }
1036 }
1038 #ifdef ASSERT
1039 // Constructor of Assert
1040 Assert::Assert(Value x, Condition cond, bool unordered_is_true, Value y) : Instruction(illegalType)
1041 , _x(x)
1042 , _cond(cond)
1043 , _y(y)
1044 {
1045 set_flag(UnorderedIsTrueFlag, unordered_is_true);
1046 assert(x->type()->tag() == y->type()->tag(), "types must match");
1047 pin();
1049 stringStream strStream;
1050 Compilation::current()->method()->print_name(&strStream);
1052 stringStream strStream1;
1053 InstructionPrinter ip1(1, &strStream1);
1054 ip1.print_instr(x);
1056 stringStream strStream2;
1057 InstructionPrinter ip2(1, &strStream2);
1058 ip2.print_instr(y);
1060 stringStream ss;
1061 ss.print("Assertion %s %s %s in method %s", strStream1.as_string(), ip2.cond_name(cond), strStream2.as_string(), strStream.as_string());
1063 _message = ss.as_string();
1064 }
1065 #endif
1067 void RangeCheckPredicate::check_state() {
1068 assert(state()->kind() != ValueStack::EmptyExceptionState && state()->kind() != ValueStack::ExceptionState, "will deopt with empty state");
1069 }
1071 void ProfileInvoke::state_values_do(ValueVisitor* f) {
1072 if (state() != NULL) state()->values_do(f);
1073 }
