1 /*
2 * Copyright 1997-2009 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 #include "incls/_precompiled.incl"
26 #include "incls/_parse1.cpp.incl"
27
28 // Static array so we can figure out which bytecodes stop us from compiling
29 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
30 // and eventually should be encapsulated in a proper class (gri 8/18/98).
31
32 int nodes_created = 0;
33 int methods_parsed = 0;
34 int methods_seen = 0;
35 int blocks_parsed = 0;
36 int blocks_seen = 0;
37
38 int explicit_null_checks_inserted = 0;
39 int explicit_null_checks_elided = 0;
40 int all_null_checks_found = 0, implicit_null_checks = 0;
41 int implicit_null_throws = 0;
42
43 int reclaim_idx = 0;
44 int reclaim_in = 0;
45 int reclaim_node = 0;
46
47 #ifndef PRODUCT
48 bool Parse::BytecodeParseHistogram::_initialized = false;
49 uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
50 uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
51 uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
52 uint Parse::BytecodeParseHistogram::_new_values [Bytecodes::number_of_codes];
53 #endif
54
55 //------------------------------print_statistics-------------------------------
56 #ifndef PRODUCT
57 void Parse::print_statistics() {
58 tty->print_cr("--- Compiler Statistics ---");
59 tty->print("Methods seen: %d Methods parsed: %d", methods_seen, methods_parsed);
60 tty->print(" Nodes created: %d", nodes_created);
61 tty->cr();
62 if (methods_seen != methods_parsed)
63 tty->print_cr("Reasons for parse failures (NOT cumulative):");
64 tty->print_cr("Blocks parsed: %d Blocks seen: %d", blocks_parsed, blocks_seen);
65
66 if( explicit_null_checks_inserted )
67 tty->print_cr("%d original NULL checks - %d elided (%2d%%); optimizer leaves %d,", explicit_null_checks_inserted, explicit_null_checks_elided, (100*explicit_null_checks_elided)/explicit_null_checks_inserted, all_null_checks_found);
68 if( all_null_checks_found )
69 tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
70 (100*implicit_null_checks)/all_null_checks_found);
71 if( implicit_null_throws )
72 tty->print_cr("%d implicit null exceptions at runtime",
73 implicit_null_throws);
74
75 if( PrintParseStatistics && BytecodeParseHistogram::initialized() ) {
76 BytecodeParseHistogram::print();
77 }
78 }
79 #endif
80
81 //------------------------------ON STACK REPLACEMENT---------------------------
82
83 // Construct a node which can be used to get incoming state for
84 // on stack replacement.
85 Node *Parse::fetch_interpreter_state(int index,
86 BasicType bt,
87 Node *local_addrs,
88 Node *local_addrs_base) {
89 Node *mem = memory(Compile::AliasIdxRaw);
90 Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
91
92 // Very similar to LoadNode::make, except we handle un-aligned longs and
93 // doubles on Sparc. Intel can handle them just fine directly.
94 Node *l;
95 switch( bt ) { // Signature is flattened
96 case T_INT: l = new (C, 3) LoadINode( 0, mem, adr, TypeRawPtr::BOTTOM ); break;
97 case T_FLOAT: l = new (C, 3) LoadFNode( 0, mem, adr, TypeRawPtr::BOTTOM ); break;
98 case T_ADDRESS: l = new (C, 3) LoadPNode( 0, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM ); break;
99 case T_OBJECT: l = new (C, 3) LoadPNode( 0, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM ); break;
100 case T_LONG:
101 case T_DOUBLE: {
102 // Since arguments are in reverse order, the argument address 'adr'
103 // refers to the back half of the long/double. Recompute adr.
104 adr = basic_plus_adr( local_addrs_base, local_addrs, -(index+1)*wordSize );
105 if( Matcher::misaligned_doubles_ok ) {
106 l = (bt == T_DOUBLE)
107 ? (Node*)new (C, 3) LoadDNode( 0, mem, adr, TypeRawPtr::BOTTOM )
108 : (Node*)new (C, 3) LoadLNode( 0, mem, adr, TypeRawPtr::BOTTOM );
109 } else {
110 l = (bt == T_DOUBLE)
111 ? (Node*)new (C, 3) LoadD_unalignedNode( 0, mem, adr, TypeRawPtr::BOTTOM )
112 : (Node*)new (C, 3) LoadL_unalignedNode( 0, mem, adr, TypeRawPtr::BOTTOM );
113 }
114 break;
115 }
116 default: ShouldNotReachHere();
117 }
118 return _gvn.transform(l);
119 }
120
121 // Helper routine to prevent the interpreter from handing
122 // unexpected typestate to an OSR method.
123 // The Node l is a value newly dug out of the interpreter frame.
124 // The type is the type predicted by ciTypeFlow. Note that it is
125 // not a general type, but can only come from Type::get_typeflow_type.
126 // The safepoint is a map which will feed an uncommon trap.
127 Node* Parse::check_interpreter_type(Node* l, const Type* type,
128 SafePointNode* &bad_type_exit) {
129
130 const TypeOopPtr* tp = type->isa_oopptr();
131
132 // TypeFlow may assert null-ness if a type appears unloaded.
133 if (type == TypePtr::NULL_PTR ||
134 (tp != NULL && !tp->klass()->is_loaded())) {
135 // Value must be null, not a real oop.
136 Node* chk = _gvn.transform( new (C, 3) CmpPNode(l, null()) );
137 Node* tst = _gvn.transform( new (C, 2) BoolNode(chk, BoolTest::eq) );
138 IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
139 set_control(_gvn.transform( new (C, 1) IfTrueNode(iff) ));
140 Node* bad_type = _gvn.transform( new (C, 1) IfFalseNode(iff) );
141 bad_type_exit->control()->add_req(bad_type);
142 l = null();
143 }
144
145 // Typeflow can also cut off paths from the CFG, based on
146 // types which appear unloaded, or call sites which appear unlinked.
147 // When paths are cut off, values at later merge points can rise
148 // toward more specific classes. Make sure these specific classes
149 // are still in effect.
150 if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
151 // TypeFlow asserted a specific object type. Value must have that type.
152 Node* bad_type_ctrl = NULL;
153 l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
154 bad_type_exit->control()->add_req(bad_type_ctrl);
155 }
156
157 BasicType bt_l = _gvn.type(l)->basic_type();
158 BasicType bt_t = type->basic_type();
159 assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
160 return l;
161 }
162
163 // Helper routine which sets up elements of the initial parser map when
164 // performing a parse for on stack replacement. Add values into map.
165 // The only parameter contains the address of a interpreter arguments.
166 void Parse::load_interpreter_state(Node* osr_buf) {
167 int index;
168 int max_locals = jvms()->loc_size();
169 int max_stack = jvms()->stk_size();
170
171
172 // Mismatch between method and jvms can occur since map briefly held
173 // an OSR entry state (which takes up one RawPtr word).
174 assert(max_locals == method()->max_locals(), "sanity");
175 assert(max_stack >= method()->max_stack(), "sanity");
176 assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
177 assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
178
179 // Find the start block.
180 Block* osr_block = start_block();
181 assert(osr_block->start() == osr_bci(), "sanity");
182
183 // Set initial BCI.
184 set_parse_bci(osr_block->start());
185
186 // Set initial stack depth.
187 set_sp(osr_block->start_sp());
188
189 // Check bailouts. We currently do not perform on stack replacement
190 // of loops in catch blocks or loops which branch with a non-empty stack.
191 if (sp() != 0) {
192 C->record_method_not_compilable("OSR starts with non-empty stack");
193 return;
194 }
195 // Do not OSR inside finally clauses:
196 if (osr_block->has_trap_at(osr_block->start())) {
197 C->record_method_not_compilable("OSR starts with an immediate trap");
198 return;
199 }
200
201 // Commute monitors from interpreter frame to compiler frame.
202 assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
203 int mcnt = osr_block->flow()->monitor_count();
204 Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
205 for (index = 0; index < mcnt; index++) {
206 // Make a BoxLockNode for the monitor.
207 Node *box = _gvn.transform(new (C, 1) BoxLockNode(next_monitor()));
208
209
210 // Displaced headers and locked objects are interleaved in the
211 // temp OSR buffer. We only copy the locked objects out here.
212 // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
213 Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
214 // Try and copy the displaced header to the BoxNode
215 Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);
216
217
218 store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw);
219
220 // Build a bogus FastLockNode (no code will be generated) and push the
221 // monitor into our debug info.
222 const FastLockNode *flock = _gvn.transform(new (C, 3) FastLockNode( 0, lock_object, box ))->as_FastLock();
223 map()->push_monitor(flock);
224
225 // If the lock is our method synchronization lock, tuck it away in
226 // _sync_lock for return and rethrow exit paths.
227 if (index == 0 && method()->is_synchronized()) {
228 _synch_lock = flock;
229 }
230 }
231
232 // Use the raw liveness computation to make sure that unexpected
233 // values don't propagate into the OSR frame.
234 MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
235 if (!live_locals.is_valid()) {
236 // Degenerate or breakpointed method.
237 C->record_method_not_compilable("OSR in empty or breakpointed method");
238 return;
239 }
240 MethodLivenessResult raw_live_locals = method()->raw_liveness_at_bci(osr_bci());
241
242 // Extract the needed locals from the interpreter frame.
243 Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);
244
245 // find all the locals that the interpreter thinks contain live oops
246 const BitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
247 for (index = 0; index < max_locals; index++) {
248
249 if (!live_locals.at(index)) {
250 continue;
251 }
252
253 const Type *type = osr_block->local_type_at(index);
254
255 if (type->isa_oopptr() != NULL) {
256
257 // 6403625: Verify that the interpreter oopMap thinks that the oop is live
258 // else we might load a stale oop if the MethodLiveness disagrees with the
259 // result of the interpreter. If the interpreter says it is dead we agree
260 // by making the value go to top.
261 //
262
263 if (!live_oops.at(index)) {
264 if (C->log() != NULL) {
265 C->log()->elem("OSR_mismatch local_index='%d'",index);
266 }
267 set_local(index, null());
268 // and ignore it for the loads
269 continue;
270 }
271 }
272
273 // Filter out TOP, HALF, and BOTTOM. (Cf. ensure_phi.)
274 if (type == Type::TOP || type == Type::HALF) {
275 continue;
276 }
277 // If the type falls to bottom, then this must be a local that
278 // is mixing ints and oops or some such. Forcing it to top
279 // makes it go dead.
280 if (type == Type::BOTTOM) {
281 continue;
282 }
283 // Construct code to access the appropriate local.
284 Node *value = fetch_interpreter_state(index, type->basic_type(), locals_addr, osr_buf);
285 set_local(index, value);
286 }
287
288 // Extract the needed stack entries from the interpreter frame.
289 for (index = 0; index < sp(); index++) {
290 const Type *type = osr_block->stack_type_at(index);
291 if (type != Type::TOP) {
292 // Currently the compiler bails out when attempting to on stack replace
293 // at a bci with a non-empty stack. We should not reach here.
294 ShouldNotReachHere();
295 }
296 }
297
298 // End the OSR migration
299 make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
300 CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
301 "OSR_migration_end", TypeRawPtr::BOTTOM,
302 osr_buf);
303
304 // Now that the interpreter state is loaded, make sure it will match
305 // at execution time what the compiler is expecting now:
306 SafePointNode* bad_type_exit = clone_map();
307 bad_type_exit->set_control(new (C, 1) RegionNode(1));
308
309 for (index = 0; index < max_locals; index++) {
310 if (stopped()) break;
311 Node* l = local(index);
312 if (l->is_top()) continue; // nothing here
313 const Type *type = osr_block->local_type_at(index);
314 if (type->isa_oopptr() != NULL) {
315 if (!live_oops.at(index)) {
316 // skip type check for dead oops
317 continue;
318 }
319 }
320 if (type->basic_type() == T_ADDRESS && !raw_live_locals.at(index)) {
321 // Skip type check for dead address locals
322 continue;
323 }
324 set_local(index, check_interpreter_type(l, type, bad_type_exit));
325 }
326
327 for (index = 0; index < sp(); index++) {
328 if (stopped()) break;
329 Node* l = stack(index);
330 if (l->is_top()) continue; // nothing here
331 const Type *type = osr_block->stack_type_at(index);
332 set_stack(index, check_interpreter_type(l, type, bad_type_exit));
333 }
334
335 if (bad_type_exit->control()->req() > 1) {
336 // Build an uncommon trap here, if any inputs can be unexpected.
337 bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
338 record_for_igvn(bad_type_exit->control());
339 SafePointNode* types_are_good = map();
340 set_map(bad_type_exit);
341 // The unexpected type happens because a new edge is active
342 // in the CFG, which typeflow had previously ignored.
343 // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
344 // This x will be typed as Integer if notReached is not yet linked.
345 uncommon_trap(Deoptimization::Reason_unreached,
346 Deoptimization::Action_reinterpret);
347 set_map(types_are_good);
348 }
349 }
350
351 //------------------------------Parse------------------------------------------
352 // Main parser constructor.
353 Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses)
354 : _exits(caller)
355 {
356 // Init some variables
357 _caller = caller;
358 _method = parse_method;
359 _expected_uses = expected_uses;
360 _depth = 1 + (caller->has_method() ? caller->depth() : 0);
361 _wrote_final = false;
362 _entry_bci = InvocationEntryBci;
363 _tf = NULL;
364 _block = NULL;
365 debug_only(_block_count = -1);
366 debug_only(_blocks = (Block*)-1);
367 #ifndef PRODUCT
368 if (PrintCompilation || PrintOpto) {
369 // Make sure I have an inline tree, so I can print messages about it.
370 JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
371 InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method, true);
372 }
373 _max_switch_depth = 0;
374 _est_switch_depth = 0;
375 #endif
376
377 _tf = TypeFunc::make(method());
378 _iter.reset_to_method(method());
379 _flow = method()->get_flow_analysis();
380 if (_flow->failing()) {
381 C->record_method_not_compilable_all_tiers(_flow->failure_reason());
382 }
383
384 #ifndef PRODUCT
385 if (_flow->has_irreducible_entry()) {
386 C->set_parsed_irreducible_loop(true);
387 }
388 #endif
389
390 if (_expected_uses <= 0) {
391 _prof_factor = 1;
392 } else {
393 float prof_total = parse_method->interpreter_invocation_count();
394 if (prof_total <= _expected_uses) {
395 _prof_factor = 1;
396 } else {
397 _prof_factor = _expected_uses / prof_total;
398 }
399 }
400
401 CompileLog* log = C->log();
402 if (log != NULL) {
403 log->begin_head("parse method='%d' uses='%g'",
404 log->identify(parse_method), expected_uses);
405 if (depth() == 1 && C->is_osr_compilation()) {
406 log->print(" osr_bci='%d'", C->entry_bci());
407 }
408 log->stamp();
409 log->end_head();
410 }
411
412 // Accumulate deoptimization counts.
413 // (The range_check and store_check counts are checked elsewhere.)
414 ciMethodData* md = method()->method_data();
415 for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
416 uint md_count = md->trap_count(reason);
417 if (md_count != 0) {
418 if (md_count == md->trap_count_limit())
419 md_count += md->overflow_trap_count();
420 uint total_count = C->trap_count(reason);
421 uint old_count = total_count;
422 total_count += md_count;
423 // Saturate the add if it overflows.
424 if (total_count < old_count || total_count < md_count)
425 total_count = (uint)-1;
426 C->set_trap_count(reason, total_count);
427 if (log != NULL)
428 log->elem("observe trap='%s' count='%d' total='%d'",
429 Deoptimization::trap_reason_name(reason),
430 md_count, total_count);
431 }
432 }
433 // Accumulate total sum of decompilations, also.
434 C->set_decompile_count(C->decompile_count() + md->decompile_count());
435
436 _count_invocations = C->do_count_invocations();
437 _method_data_update = C->do_method_data_update();
438
439 if (log != NULL && method()->has_exception_handlers()) {
440 log->elem("observe that='has_exception_handlers'");
441 }
442
443 assert(method()->can_be_compiled(), "Can not parse this method, cutout earlier");
444 assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
445
446 // Always register dependence if JVMTI is enabled, because
447 // either breakpoint setting or hotswapping of methods may
448 // cause deoptimization.
449 if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
450 C->dependencies()->assert_evol_method(method());
451 }
452
453 methods_seen++;
454
455 // Do some special top-level things.
456 if (depth() == 1 && C->is_osr_compilation()) {
457 _entry_bci = C->entry_bci();
458 _flow = method()->get_osr_flow_analysis(osr_bci());
459 if (_flow->failing()) {
460 C->record_method_not_compilable(_flow->failure_reason());
461 #ifndef PRODUCT
462 if (PrintOpto && (Verbose || WizardMode)) {
463 tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
464 if (Verbose) {
465 method()->print_oop();
466 method()->print_codes();
467 _flow->print();
468 }
469 }
470 #endif
471 }
472 _tf = C->tf(); // the OSR entry type is different
473 }
474
475 #ifdef ASSERT
476 if (depth() == 1) {
477 assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
478 if (C->tf() != tf()) {
479 MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
480 assert(C->env()->system_dictionary_modification_counter_changed(),
481 "Must invalidate if TypeFuncs differ");
482 }
483 } else {
484 assert(!this->is_osr_parse(), "no recursive OSR");
485 }
486 #endif
487
488 methods_parsed++;
489 #ifndef PRODUCT
490 // add method size here to guarantee that inlined methods are added too
491 if (TimeCompiler)
492 _total_bytes_compiled += method()->code_size();
493
494 show_parse_info();
495 #endif
496
497 if (failing()) {
498 if (log) log->done("parse");
499 return;
500 }
501
502 gvn().set_type(root(), root()->bottom_type());
503 gvn().transform(top());
504
505 // Import the results of the ciTypeFlow.
506 init_blocks();
507
508 // Merge point for all normal exits
509 build_exits();
510
511 // Setup the initial JVM state map.
512 SafePointNode* entry_map = create_entry_map();
513
514 // Check for bailouts during map initialization
515 if (failing() || entry_map == NULL) {
516 if (log) log->done("parse");
517 return;
518 }
519
520 Node_Notes* caller_nn = C->default_node_notes();
521 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
522 if (DebugInlinedCalls || depth() == 1) {
523 C->set_default_node_notes(make_node_notes(caller_nn));
524 }
525
526 if (is_osr_parse()) {
527 Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
528 entry_map->set_req(TypeFunc::Parms+0, top());
529 set_map(entry_map);
530 load_interpreter_state(osr_buf);
531 } else {
532 set_map(entry_map);
533 do_method_entry();
534 }
535
536 // Check for bailouts during method entry.
537 if (failing()) {
538 if (log) log->done("parse");
539 C->set_default_node_notes(caller_nn);
540 return;
541 }
542
543 entry_map = map(); // capture any changes performed by method setup code
544 assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
545
546 // We begin parsing as if we have just encountered a jump to the
547 // method entry.
548 Block* entry_block = start_block();
549 assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
550 set_map_clone(entry_map);
551 merge_common(entry_block, entry_block->next_path_num());
552
553 #ifndef PRODUCT
554 BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
555 set_parse_histogram( parse_histogram_obj );
556 #endif
557
558 // Parse all the basic blocks.
559 do_all_blocks();
560
561 C->set_default_node_notes(caller_nn);
562
563 // Check for bailouts during conversion to graph
564 if (failing()) {
565 if (log) log->done("parse");
566 return;
567 }
568
569 // Fix up all exiting control flow.
570 set_map(entry_map);
571 do_exits();
572
573 if (log) log->done("parse nodes='%d' memory='%d'",
574 C->unique(), C->node_arena()->used());
575 }
576
577 //---------------------------do_all_blocks-------------------------------------
578 void Parse::do_all_blocks() {
579 bool has_irreducible = flow()->has_irreducible_entry();
580
581 // Walk over all blocks in Reverse Post-Order.
582 while (true) {
583 bool progress = false;
584 for (int rpo = 0; rpo < block_count(); rpo++) {
585 Block* block = rpo_at(rpo);
586
587 if (block->is_parsed()) continue;
588
589 if (!block->is_merged()) {
590 // Dead block, no state reaches this block
591 continue;
592 }
593
594 // Prepare to parse this block.
595 load_state_from(block);
596
597 if (stopped()) {
598 // Block is dead.
599 continue;
600 }
601
602 blocks_parsed++;
603
604 progress = true;
605 if (block->is_loop_head() || block->is_handler() || has_irreducible && !block->is_ready()) {
606 // Not all preds have been parsed. We must build phis everywhere.
607 // (Note that dead locals do not get phis built, ever.)
608 ensure_phis_everywhere();
609
610 // Leave behind an undisturbed copy of the map, for future merges.
611 set_map(clone_map());
612 }
613
614 if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
615 // In the absence of irreducible loops, the Region and Phis
616 // associated with a merge that doesn't involve a backedge can
617 // be simplified now since the RPO parsing order guarantees
618 // that any path which was supposed to reach here has already
619 // been parsed or must be dead.
620 Node* c = control();
621 Node* result = _gvn.transform_no_reclaim(control());
622 if (c != result && TraceOptoParse) {
623 tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
624 }
625 if (result != top()) {
626 record_for_igvn(result);
627 }
628 }
629
630 // Parse the block.
631 do_one_block();
632
633 // Check for bailouts.
634 if (failing()) return;
635 }
636
637 // with irreducible loops multiple passes might be necessary to parse everything
638 if (!has_irreducible || !progress) {
639 break;
640 }
641 }
642
643 blocks_seen += block_count();
644
645 #ifndef PRODUCT
646 // Make sure there are no half-processed blocks remaining.
647 // Every remaining unprocessed block is dead and may be ignored now.
648 for (int rpo = 0; rpo < block_count(); rpo++) {
649 Block* block = rpo_at(rpo);
650 if (!block->is_parsed()) {
651 if (TraceOptoParse) {
652 tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
653 }
654 assert(!block->is_merged(), "no half-processed blocks");
655 }
656 }
657 #endif
658 }
659
660 //-------------------------------build_exits----------------------------------
661 // Build normal and exceptional exit merge points.
662 void Parse::build_exits() {
663 // make a clone of caller to prevent sharing of side-effects
664 _exits.set_map(_exits.clone_map());
665 _exits.clean_stack(_exits.sp());
666 _exits.sync_jvms();
667
668 RegionNode* region = new (C, 1) RegionNode(1);
669 record_for_igvn(region);
670 gvn().set_type_bottom(region);
671 _exits.set_control(region);
672
673 // Note: iophi and memphi are not transformed until do_exits.
674 Node* iophi = new (C, region->req()) PhiNode(region, Type::ABIO);
675 Node* memphi = new (C, region->req()) PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
676 _exits.set_i_o(iophi);
677 _exits.set_all_memory(memphi);
678
679 // Add a return value to the exit state. (Do not push it yet.)
680 if (tf()->range()->cnt() > TypeFunc::Parms) {
681 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
682 // Don't "bind" an unloaded return klass to the ret_phi. If the klass
683 // becomes loaded during the subsequent parsing, the loaded and unloaded
684 // types will not join when we transform and push in do_exits().
685 const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
686 if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
687 ret_type = TypeOopPtr::BOTTOM;
688 }
689 int ret_size = type2size[ret_type->basic_type()];
690 Node* ret_phi = new (C, region->req()) PhiNode(region, ret_type);
691 _exits.ensure_stack(ret_size);
692 assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
693 assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
694 _exits.set_argument(0, ret_phi); // here is where the parser finds it
695 // Note: ret_phi is not yet pushed, until do_exits.
696 }
697 }
698
699
700 //----------------------------build_start_state-------------------------------
701 // Construct a state which contains only the incoming arguments from an
702 // unknown caller. The method & bci will be NULL & InvocationEntryBci.
703 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
704 int arg_size = tf->domain()->cnt();
705 int max_size = MAX2(arg_size, (int)tf->range()->cnt());
706 JVMState* jvms = new (this) JVMState(max_size - TypeFunc::Parms);
707 SafePointNode* map = new (this, max_size) SafePointNode(max_size, NULL);
708 record_for_igvn(map);
709 assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
710 Node_Notes* old_nn = default_node_notes();
711 if (old_nn != NULL && has_method()) {
712 Node_Notes* entry_nn = old_nn->clone(this);
713 JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
714 entry_jvms->set_offsets(0);
715 entry_jvms->set_bci(entry_bci());
716 entry_nn->set_jvms(entry_jvms);
717 set_default_node_notes(entry_nn);
718 }
719 uint i;
720 for (i = 0; i < (uint)arg_size; i++) {
721 Node* parm = initial_gvn()->transform(new (this, 1) ParmNode(start, i));
722 map->init_req(i, parm);
723 // Record all these guys for later GVN.
724 record_for_igvn(parm);
725 }
726 for (; i < map->req(); i++) {
727 map->init_req(i, top());
728 }
729 assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
730 set_default_node_notes(old_nn);
731 map->set_jvms(jvms);
732 jvms->set_map(map);
733 return jvms;
734 }
735
736 //-----------------------------make_node_notes---------------------------------
737 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
738 if (caller_nn == NULL) return NULL;
739 Node_Notes* nn = caller_nn->clone(C);
740 JVMState* caller_jvms = nn->jvms();
741 JVMState* jvms = new (C) JVMState(method(), caller_jvms);
742 jvms->set_offsets(0);
743 jvms->set_bci(_entry_bci);
744 nn->set_jvms(jvms);
745 return nn;
746 }
747
748
749 //--------------------------return_values--------------------------------------
750 void Compile::return_values(JVMState* jvms) {
751 GraphKit kit(jvms);
752 Node* ret = new (this, TypeFunc::Parms) ReturnNode(TypeFunc::Parms,
753 kit.control(),
754 kit.i_o(),
755 kit.reset_memory(),
756 kit.frameptr(),
757 kit.returnadr());
758 // Add zero or 1 return values
759 int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
760 if (ret_size > 0) {
761 kit.inc_sp(-ret_size); // pop the return value(s)
762 kit.sync_jvms();
763 ret->add_req(kit.argument(0));
764 // Note: The second dummy edge is not needed by a ReturnNode.
765 }
766 // bind it to root
767 root()->add_req(ret);
768 record_for_igvn(ret);
769 initial_gvn()->transform_no_reclaim(ret);
770 }
771
772 //------------------------rethrow_exceptions-----------------------------------
773 // Bind all exception states in the list into a single RethrowNode.
774 void Compile::rethrow_exceptions(JVMState* jvms) {
775 GraphKit kit(jvms);
776 if (!kit.has_exceptions()) return; // nothing to generate
777 // Load my combined exception state into the kit, with all phis transformed:
778 SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
779 Node* ex_oop = kit.use_exception_state(ex_map);
780 RethrowNode* exit = new (this, TypeFunc::Parms + 1) RethrowNode(kit.control(),
781 kit.i_o(), kit.reset_memory(),
782 kit.frameptr(), kit.returnadr(),
783 // like a return but with exception input
784 ex_oop);
785 // bind to root
786 root()->add_req(exit);
787 record_for_igvn(exit);
788 initial_gvn()->transform_no_reclaim(exit);
789 }
790
791 bool Parse::can_rerun_bytecode() {
792 switch (bc()) {
793 case Bytecodes::_ldc:
794 case Bytecodes::_ldc_w:
795 case Bytecodes::_ldc2_w:
796 case Bytecodes::_getfield:
797 case Bytecodes::_putfield:
798 case Bytecodes::_getstatic:
799 case Bytecodes::_putstatic:
800 case Bytecodes::_arraylength:
801 case Bytecodes::_baload:
802 case Bytecodes::_caload:
803 case Bytecodes::_iaload:
804 case Bytecodes::_saload:
805 case Bytecodes::_faload:
806 case Bytecodes::_aaload:
807 case Bytecodes::_laload:
808 case Bytecodes::_daload:
809 case Bytecodes::_bastore:
810 case Bytecodes::_castore:
811 case Bytecodes::_iastore:
812 case Bytecodes::_sastore:
813 case Bytecodes::_fastore:
814 case Bytecodes::_aastore:
815 case Bytecodes::_lastore:
816 case Bytecodes::_dastore:
817 case Bytecodes::_irem:
818 case Bytecodes::_idiv:
819 case Bytecodes::_lrem:
820 case Bytecodes::_ldiv:
821 case Bytecodes::_frem:
822 case Bytecodes::_fdiv:
823 case Bytecodes::_drem:
824 case Bytecodes::_ddiv:
825 case Bytecodes::_checkcast:
826 case Bytecodes::_instanceof:
827 case Bytecodes::_athrow:
828 case Bytecodes::_anewarray:
829 case Bytecodes::_newarray:
830 case Bytecodes::_multianewarray:
831 case Bytecodes::_new:
832 case Bytecodes::_monitorenter: // can re-run initial null check, only
833 case Bytecodes::_return:
834 return true;
835 break;
836
837 case Bytecodes::_invokestatic:
838 case Bytecodes::_invokedynamic:
839 case Bytecodes::_invokespecial:
840 case Bytecodes::_invokevirtual:
841 case Bytecodes::_invokeinterface:
842 return false;
843 break;
844
845 default:
846 assert(false, "unexpected bytecode produced an exception");
847 return true;
848 }
849 }
850
851 //---------------------------do_exceptions-------------------------------------
852 // Process exceptions arising from the current bytecode.
853 // Send caught exceptions to the proper handler within this method.
854 // Unhandled exceptions feed into _exit.
855 void Parse::do_exceptions() {
856 if (!has_exceptions()) return;
857
858 if (failing()) {
859 // Pop them all off and throw them away.
860 while (pop_exception_state() != NULL) ;
861 return;
862 }
863
864 // Make sure we can classify this bytecode if we need to.
865 debug_only(can_rerun_bytecode());
866
867 PreserveJVMState pjvms(this, false);
868
869 SafePointNode* ex_map;
870 while ((ex_map = pop_exception_state()) != NULL) {
871 if (!method()->has_exception_handlers()) {
872 // Common case: Transfer control outward.
873 // Doing it this early allows the exceptions to common up
874 // even between adjacent method calls.
875 throw_to_exit(ex_map);
876 } else {
877 // Have to look at the exception first.
878 assert(stopped(), "catch_inline_exceptions trashes the map");
879 catch_inline_exceptions(ex_map);
880 stop_and_kill_map(); // we used up this exception state; kill it
881 }
882 }
883
884 // We now return to our regularly scheduled program:
885 }
886
887 //---------------------------throw_to_exit-------------------------------------
888 // Merge the given map into an exception exit from this method.
889 // The exception exit will handle any unlocking of receiver.
890 // The ex_oop must be saved within the ex_map, unlike merge_exception.
891 void Parse::throw_to_exit(SafePointNode* ex_map) {
892 // Pop the JVMS to (a copy of) the caller.
893 GraphKit caller;
894 caller.set_map_clone(_caller->map());
895 caller.set_bci(_caller->bci());
896 caller.set_sp(_caller->sp());
897 // Copy out the standard machine state:
898 for (uint i = 0; i < TypeFunc::Parms; i++) {
899 caller.map()->set_req(i, ex_map->in(i));
900 }
901 // ...and the exception:
902 Node* ex_oop = saved_ex_oop(ex_map);
903 SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
904 // Finally, collect the new exception state in my exits:
905 _exits.add_exception_state(caller_ex_map);
906 }
907
908 //------------------------------do_exits---------------------------------------
909 void Parse::do_exits() {
910 set_parse_bci(InvocationEntryBci);
911
912 // Now peephole on the return bits
913 Node* region = _exits.control();
914 _exits.set_control(gvn().transform(region));
915
916 Node* iophi = _exits.i_o();
917 _exits.set_i_o(gvn().transform(iophi));
918
919 if (wrote_final()) {
920 // This method (which must be a constructor by the rules of Java)
921 // wrote a final. The effects of all initializations must be
922 // committed to memory before any code after the constructor
923 // publishes the reference to the newly constructor object.
924 // Rather than wait for the publication, we simply block the
925 // writes here. Rather than put a barrier on only those writes
926 // which are required to complete, we force all writes to complete.
927 //
928 // "All bets are off" unless the first publication occurs after a
929 // normal return from the constructor. We do not attempt to detect
930 // such unusual early publications. But no barrier is needed on
931 // exceptional returns, since they cannot publish normally.
932 //
933 _exits.insert_mem_bar(Op_MemBarRelease);
934 #ifndef PRODUCT
935 if (PrintOpto && (Verbose || WizardMode)) {
936 method()->print_name();
937 tty->print_cr(" writes finals and needs a memory barrier");
938 }
939 #endif
940 }
941
942 for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
943 // transform each slice of the original memphi:
944 mms.set_memory(_gvn.transform(mms.memory()));
945 }
946
947 if (tf()->range()->cnt() > TypeFunc::Parms) {
948 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
949 Node* ret_phi = _gvn.transform( _exits.argument(0) );
950 assert(_exits.control()->is_top() || !_gvn.type(ret_phi)->empty(), "return value must be well defined");
951 _exits.push_node(ret_type->basic_type(), ret_phi);
952 }
953
954 // Note: Logic for creating and optimizing the ReturnNode is in Compile.
955
956 // Unlock along the exceptional paths.
957 // This is done late so that we can common up equivalent exceptions
958 // (e.g., null checks) arising from multiple points within this method.
959 // See GraphKit::add_exception_state, which performs the commoning.
960 bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
961
962 // record exit from a method if compiled while Dtrace is turned on.
963 if (do_synch || C->env()->dtrace_method_probes()) {
964 // First move the exception list out of _exits:
965 GraphKit kit(_exits.transfer_exceptions_into_jvms());
966 SafePointNode* normal_map = kit.map(); // keep this guy safe
967 // Now re-collect the exceptions into _exits:
968 SafePointNode* ex_map;
969 while ((ex_map = kit.pop_exception_state()) != NULL) {
970 Node* ex_oop = kit.use_exception_state(ex_map);
971 // Force the exiting JVM state to have this method at InvocationEntryBci.
972 // The exiting JVM state is otherwise a copy of the calling JVMS.
973 JVMState* caller = kit.jvms();
974 JVMState* ex_jvms = caller->clone_shallow(C);
975 ex_jvms->set_map(kit.clone_map());
976 ex_jvms->map()->set_jvms(ex_jvms);
977 ex_jvms->set_bci( InvocationEntryBci);
978 kit.set_jvms(ex_jvms);
979 if (do_synch) {
980 // Add on the synchronized-method box/object combo
981 kit.map()->push_monitor(_synch_lock);
982 // Unlock!
983 kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
984 }
985 if (C->env()->dtrace_method_probes()) {
986 kit.make_dtrace_method_exit(method());
987 }
988 // Done with exception-path processing.
989 ex_map = kit.make_exception_state(ex_oop);
990 assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
991 // Pop the last vestige of this method:
992 ex_map->set_jvms(caller->clone_shallow(C));
993 ex_map->jvms()->set_map(ex_map);
994 _exits.push_exception_state(ex_map);
995 }
996 assert(_exits.map() == normal_map, "keep the same return state");
997 }
998
999 {
1000 // Capture very early exceptions (receiver null checks) from caller JVMS
1001 GraphKit caller(_caller);
1002 SafePointNode* ex_map;
1003 while ((ex_map = caller.pop_exception_state()) != NULL) {
1004 _exits.add_exception_state(ex_map);
1005 }
1006 }
1007 }
1008
1009 //-----------------------------create_entry_map-------------------------------
1010 // Initialize our parser map to contain the types at method entry.
1011 // For OSR, the map contains a single RawPtr parameter.
1012 // Initial monitor locking for sync. methods is performed by do_method_entry.
1013 SafePointNode* Parse::create_entry_map() {
1014 // Check for really stupid bail-out cases.
1015 uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1016 if (len >= 32760) {
1017 C->record_method_not_compilable_all_tiers("too many local variables");
1018 return NULL;
1019 }
1020
1021 // If this is an inlined method, we may have to do a receiver null check.
1022 if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1023 GraphKit kit(_caller);
1024 kit.null_check_receiver(method());
1025 _caller = kit.transfer_exceptions_into_jvms();
1026 if (kit.stopped()) {
1027 _exits.add_exception_states_from(_caller);
1028 _exits.set_jvms(_caller);
1029 return NULL;
1030 }
1031 }
1032
1033 assert(method() != NULL, "parser must have a method");
1034
1035 // Create an initial safepoint to hold JVM state during parsing
1036 JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1037 set_map(new (C, len) SafePointNode(len, jvms));
1038 jvms->set_map(map());
1039 record_for_igvn(map());
1040 assert(jvms->endoff() == len, "correct jvms sizing");
1041
1042 SafePointNode* inmap = _caller->map();
1043 assert(inmap != NULL, "must have inmap");
1044
1045 uint i;
1046
1047 // Pass thru the predefined input parameters.
1048 for (i = 0; i < TypeFunc::Parms; i++) {
1049 map()->init_req(i, inmap->in(i));
1050 }
1051
1052 if (depth() == 1) {
1053 assert(map()->memory()->Opcode() == Op_Parm, "");
1054 // Insert the memory aliasing node
1055 set_all_memory(reset_memory());
1056 }
1057 assert(merged_memory(), "");
1058
1059 // Now add the locals which are initially bound to arguments:
1060 uint arg_size = tf()->domain()->cnt();
1061 ensure_stack(arg_size - TypeFunc::Parms); // OSR methods have funny args
1062 for (i = TypeFunc::Parms; i < arg_size; i++) {
1063 map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1064 }
1065
1066 // Clear out the rest of the map (locals and stack)
1067 for (i = arg_size; i < len; i++) {
1068 map()->init_req(i, top());
1069 }
1070
1071 SafePointNode* entry_map = stop();
1072 return entry_map;
1073 }
1074
1075 //-----------------------------do_method_entry--------------------------------
1076 // Emit any code needed in the pseudo-block before BCI zero.
1077 // The main thing to do is lock the receiver of a synchronized method.
1078 void Parse::do_method_entry() {
1079 set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1080 set_sp(0); // Java Stack Pointer
1081
1082 NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1083
1084 if (C->env()->dtrace_method_probes()) {
1085 make_dtrace_method_entry(method());
1086 }
1087
1088 // If the method is synchronized, we need to construct a lock node, attach
1089 // it to the Start node, and pin it there.
1090 if (method()->is_synchronized()) {
1091 // Insert a FastLockNode right after the Start which takes as arguments
1092 // the current thread pointer, the "this" pointer & the address of the
1093 // stack slot pair used for the lock. The "this" pointer is a projection
1094 // off the start node, but the locking spot has to be constructed by
1095 // creating a ConLNode of 0, and boxing it with a BoxLockNode. The BoxLockNode
1096 // becomes the second argument to the FastLockNode call. The
1097 // FastLockNode becomes the new control parent to pin it to the start.
1098
1099 // Setup Object Pointer
1100 Node *lock_obj = NULL;
1101 if(method()->is_static()) {
1102 ciInstance* mirror = _method->holder()->java_mirror();
1103 const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1104 lock_obj = makecon(t_lock);
1105 } else { // Else pass the "this" pointer,
1106 lock_obj = local(0); // which is Parm0 from StartNode
1107 }
1108 // Clear out dead values from the debug info.
1109 kill_dead_locals();
1110 // Build the FastLockNode
1111 _synch_lock = shared_lock(lock_obj);
1112 }
1113
1114 if (depth() == 1) {
1115 increment_and_test_invocation_counter(Tier2CompileThreshold);
1116 }
1117 }
1118
1119 //------------------------------init_blocks------------------------------------
1120 // Initialize our parser map to contain the types/monitors at method entry.
1121 void Parse::init_blocks() {
1122 // Create the blocks.
1123 _block_count = flow()->block_count();
1124 _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
1125 Copy::zero_to_bytes(_blocks, sizeof(Block)*_block_count);
1126
1127 int rpo;
1128
1129 // Initialize the structs.
1130 for (rpo = 0; rpo < block_count(); rpo++) {
1131 Block* block = rpo_at(rpo);
1132 block->init_node(this, rpo);
1133 }
1134
1135 // Collect predecessor and successor information.
1136 for (rpo = 0; rpo < block_count(); rpo++) {
1137 Block* block = rpo_at(rpo);
1138 block->init_graph(this);
1139 }
1140 }
1141
1142 //-------------------------------init_node-------------------------------------
1143 void Parse::Block::init_node(Parse* outer, int rpo) {
1144 _flow = outer->flow()->rpo_at(rpo);
1145 _pred_count = 0;
1146 _preds_parsed = 0;
1147 _count = 0;
1148 assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
1149 assert(!(is_merged() || is_parsed() || is_handler()), "sanity");
1150 assert(_live_locals.size() == 0, "sanity");
1151
1152 // entry point has additional predecessor
1153 if (flow()->is_start()) _pred_count++;
1154 assert(flow()->is_start() == (this == outer->start_block()), "");
1155 }
1156
1157 //-------------------------------init_graph------------------------------------
1158 void Parse::Block::init_graph(Parse* outer) {
1159 // Create the successor list for this parser block.
1160 GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
1161 GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
1162 int ns = tfs->length();
1163 int ne = tfe->length();
1164 _num_successors = ns;
1165 _all_successors = ns+ne;
1166 _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
1167 int p = 0;
1168 for (int i = 0; i < ns+ne; i++) {
1169 ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
1170 Block* block2 = outer->rpo_at(tf2->rpo());
1171 _successors[i] = block2;
1172
1173 // Accumulate pred info for the other block, too.
1174 if (i < ns) {
1175 block2->_pred_count++;
1176 } else {
1177 block2->_is_handler = true;
1178 }
1179
1180 #ifdef ASSERT
1181 // A block's successors must be distinguishable by BCI.
1182 // That is, no bytecode is allowed to branch to two different
1183 // clones of the same code location.
1184 for (int j = 0; j < i; j++) {
1185 Block* block1 = _successors[j];
1186 if (block1 == block2) continue; // duplicates are OK
1187 assert(block1->start() != block2->start(), "successors have unique bcis");
1188 }
1189 #endif
1190 }
1191
1192 // Note: We never call next_path_num along exception paths, so they
1193 // never get processed as "ready". Also, the input phis of exception
1194 // handlers get specially processed, so that
1195 }
1196
1197 //---------------------------successor_for_bci---------------------------------
1198 Parse::Block* Parse::Block::successor_for_bci(int bci) {
1199 for (int i = 0; i < all_successors(); i++) {
1200 Block* block2 = successor_at(i);
1201 if (block2->start() == bci) return block2;
1202 }
1203 // We can actually reach here if ciTypeFlow traps out a block
1204 // due to an unloaded class, and concurrently with compilation the
1205 // class is then loaded, so that a later phase of the parser is
1206 // able to see more of the bytecode CFG. Or, the flow pass and
1207 // the parser can have a minor difference of opinion about executability
1208 // of bytecodes. For example, "obj.field = null" is executable even
1209 // if the field's type is an unloaded class; the flow pass used to
1210 // make a trap for such code.
1211 return NULL;
1212 }
1213
1214
1215 //-----------------------------stack_type_at-----------------------------------
1216 const Type* Parse::Block::stack_type_at(int i) const {
1217 return get_type(flow()->stack_type_at(i));
1218 }
1219
1220
1221 //-----------------------------local_type_at-----------------------------------
1222 const Type* Parse::Block::local_type_at(int i) const {
1223 // Make dead locals fall to bottom.
1224 if (_live_locals.size() == 0) {
1225 MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
1226 // This bitmap can be zero length if we saw a breakpoint.
1227 // In such cases, pretend they are all live.
1228 ((Block*)this)->_live_locals = live_locals;
1229 }
1230 if (_live_locals.size() > 0 && !_live_locals.at(i))
1231 return Type::BOTTOM;
1232
1233 return get_type(flow()->local_type_at(i));
1234 }
1235
1236
1237 #ifndef PRODUCT
1238
1239 //----------------------------name_for_bc--------------------------------------
1240 // helper method for BytecodeParseHistogram
1241 static const char* name_for_bc(int i) {
1242 return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
1243 }
1244
1245 //----------------------------BytecodeParseHistogram------------------------------------
1246 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
1247 _parser = p;
1248 _compiler = c;
1249 if( ! _initialized ) { _initialized = true; reset(); }
1250 }
1251
1252 //----------------------------current_count------------------------------------
1253 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
1254 switch( bph_type ) {
1255 case BPH_transforms: { return _parser->gvn().made_progress(); }
1256 case BPH_values: { return _parser->gvn().made_new_values(); }
1257 default: { ShouldNotReachHere(); return 0; }
1258 }
1259 }
1260
1261 //----------------------------initialized--------------------------------------
1262 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
1263
1264 //----------------------------reset--------------------------------------------
1265 void Parse::BytecodeParseHistogram::reset() {
1266 int i = Bytecodes::number_of_codes;
1267 while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
1268 }
1269
1270 //----------------------------set_initial_state--------------------------------
1271 // Record info when starting to parse one bytecode
1272 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
1273 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1274 _initial_bytecode = bc;
1275 _initial_node_count = _compiler->unique();
1276 _initial_transforms = current_count(BPH_transforms);
1277 _initial_values = current_count(BPH_values);
1278 }
1279 }
1280
1281 //----------------------------record_change--------------------------------
1282 // Record results of parsing one bytecode
1283 void Parse::BytecodeParseHistogram::record_change() {
1284 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1285 ++_bytecodes_parsed[_initial_bytecode];
1286 _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
1287 _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
1288 _new_values [_initial_bytecode] += (current_count(BPH_values) - _initial_values);
1289 }
1290 }
1291
1292
1293 //----------------------------print--------------------------------------------
1294 void Parse::BytecodeParseHistogram::print(float cutoff) {
1295 ResourceMark rm;
1296 // print profile
1297 int total = 0;
1298 int i = 0;
1299 for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
1300 int abs_sum = 0;
1301 tty->cr(); //0123456789012345678901234567890123456789012345678901234567890123456789
1302 tty->print_cr("Histogram of %d parsed bytecodes:", total);
1303 if( total == 0 ) { return; }
1304 tty->cr();
1305 tty->print_cr("absolute: count of compiled bytecodes of this type");
1306 tty->print_cr("relative: percentage contribution to compiled nodes");
1307 tty->print_cr("nodes : Average number of nodes constructed per bytecode");
1308 tty->print_cr("rnodes : Significance towards total nodes constructed, (nodes*relative)");
1309 tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
1310 tty->print_cr("values : Average number of node values improved per bytecode");
1311 tty->print_cr("name : Bytecode name");
1312 tty->cr();
1313 tty->print_cr(" absolute relative nodes rnodes transforms values name");
1314 tty->print_cr("----------------------------------------------------------------------");
1315 while (--i > 0) {
1316 int abs = _bytecodes_parsed[i];
1317 float rel = abs * 100.0F / total;
1318 float nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
1319 float rnodes = _bytecodes_parsed[i] == 0 ? 0 : rel * nodes;
1320 float xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
1321 float values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values [i])/_bytecodes_parsed[i];
1322 if (cutoff <= rel) {
1323 tty->print_cr("%10d %7.2f%% %6.1f %6.2f %6.1f %6.1f %s", abs, rel, nodes, rnodes, xforms, values, name_for_bc(i));
1324 abs_sum += abs;
1325 }
1326 }
1327 tty->print_cr("----------------------------------------------------------------------");
1328 float rel_sum = abs_sum * 100.0F / total;
1329 tty->print_cr("%10d %7.2f%% (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
1330 tty->print_cr("----------------------------------------------------------------------");
1331 tty->cr();
1332 }
1333 #endif
1334
1335 //----------------------------load_state_from----------------------------------
1336 // Load block/map/sp. But not do not touch iter/bci.
1337 void Parse::load_state_from(Block* block) {
1338 set_block(block);
1339 // load the block's JVM state:
1340 set_map(block->start_map());
1341 set_sp( block->start_sp());
1342 }
1343
1344
1345 //-----------------------------record_state------------------------------------
1346 void Parse::Block::record_state(Parse* p) {
1347 assert(!is_merged(), "can only record state once, on 1st inflow");
1348 assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
1349 set_start_map(p->stop());
1350 }
1351
1352
1353 //------------------------------do_one_block-----------------------------------
1354 void Parse::do_one_block() {
1355 if (TraceOptoParse) {
1356 Block *b = block();
1357 int ns = b->num_successors();
1358 int nt = b->all_successors();
1359
1360 tty->print("Parsing block #%d at bci [%d,%d), successors: ",
1361 block()->rpo(), block()->start(), block()->limit());
1362 for (int i = 0; i < nt; i++) {
1363 tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
1364 }
1365 if (b->is_loop_head()) tty->print(" lphd");
1366 tty->print_cr("");
1367 }
1368
1369 assert(block()->is_merged(), "must be merged before being parsed");
1370 block()->mark_parsed();
1371 ++_blocks_parsed;
1372
1373 // Set iterator to start of block.
1374 iter().reset_to_bci(block()->start());
1375
1376 CompileLog* log = C->log();
1377
1378 // Parse bytecodes
1379 while (!stopped() && !failing()) {
1380 iter().next();
1381
1382 // Learn the current bci from the iterator:
1383 set_parse_bci(iter().cur_bci());
1384
1385 if (bci() == block()->limit()) {
1386 // Do not walk into the next block until directed by do_all_blocks.
1387 merge(bci());
1388 break;
1389 }
1390 assert(bci() < block()->limit(), "bci still in block");
1391
1392 if (log != NULL) {
1393 // Output an optional context marker, to help place actions
1394 // that occur during parsing of this BC. If there is no log
1395 // output until the next context string, this context string
1396 // will be silently ignored.
1397 log->context()->reset();
1398 log->context()->print_cr("<bc code='%d' bci='%d'/>", (int)bc(), bci());
1399 }
1400
1401 if (block()->has_trap_at(bci())) {
1402 // We must respect the flow pass's traps, because it will refuse
1403 // to produce successors for trapping blocks.
1404 int trap_index = block()->flow()->trap_index();
1405 assert(trap_index != 0, "trap index must be valid");
1406 uncommon_trap(trap_index);
1407 break;
1408 }
1409
1410 NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1411
1412 #ifdef ASSERT
1413 int pre_bc_sp = sp();
1414 int inputs, depth;
1415 bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1416 assert(!have_se || pre_bc_sp >= inputs, "have enough stack to execute this BC");
1417 #endif //ASSERT
1418
1419 do_one_bytecode();
1420
1421 assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth, "correct depth prediction");
1422
1423 do_exceptions();
1424
1425 NOT_PRODUCT( parse_histogram()->record_change(); );
1426
1427 if (log != NULL) log->context()->reset(); // done w/ this one
1428
1429 // Fall into next bytecode. Each bytecode normally has 1 sequential
1430 // successor which is typically made ready by visiting this bytecode.
1431 // If the successor has several predecessors, then it is a merge
1432 // point, starts a new basic block, and is handled like other basic blocks.
1433 }
1434 }
1435
1436
1437 //------------------------------merge------------------------------------------
1438 void Parse::set_parse_bci(int bci) {
1439 set_bci(bci);
1440 Node_Notes* nn = C->default_node_notes();
1441 if (nn == NULL) return;
1442
1443 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
1444 if (!DebugInlinedCalls && depth() > 1) {
1445 return;
1446 }
1447
1448 // Update the JVMS annotation, if present.
1449 JVMState* jvms = nn->jvms();
1450 if (jvms != NULL && jvms->bci() != bci) {
1451 // Update the JVMS.
1452 jvms = jvms->clone_shallow(C);
1453 jvms->set_bci(bci);
1454 nn->set_jvms(jvms);
1455 }
1456 }
1457
1458 //------------------------------merge------------------------------------------
1459 // Merge the current mapping into the basic block starting at bci
1460 void Parse::merge(int target_bci) {
1461 Block* target = successor_for_bci(target_bci);
1462 if (target == NULL) { handle_missing_successor(target_bci); return; }
1463 assert(!target->is_ready(), "our arrival must be expected");
1464 int pnum = target->next_path_num();
1465 merge_common(target, pnum);
1466 }
1467
1468 //-------------------------merge_new_path--------------------------------------
1469 // Merge the current mapping into the basic block, using a new path
1470 void Parse::merge_new_path(int target_bci) {
1471 Block* target = successor_for_bci(target_bci);
1472 if (target == NULL) { handle_missing_successor(target_bci); return; }
1473 assert(!target->is_ready(), "new path into frozen graph");
1474 int pnum = target->add_new_path();
1475 merge_common(target, pnum);
1476 }
1477
1478 //-------------------------merge_exception-------------------------------------
1479 // Merge the current mapping into the basic block starting at bci
1480 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
1481 void Parse::merge_exception(int target_bci) {
1482 assert(sp() == 1, "must have only the throw exception on the stack");
1483 Block* target = successor_for_bci(target_bci);
1484 if (target == NULL) { handle_missing_successor(target_bci); return; }
1485 assert(target->is_handler(), "exceptions are handled by special blocks");
1486 int pnum = target->add_new_path();
1487 merge_common(target, pnum);
1488 }
1489
1490 //--------------------handle_missing_successor---------------------------------
1491 void Parse::handle_missing_successor(int target_bci) {
1492 #ifndef PRODUCT
1493 Block* b = block();
1494 int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1495 tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1496 #endif
1497 ShouldNotReachHere();
1498 }
1499
1500 //--------------------------merge_common---------------------------------------
1501 void Parse::merge_common(Parse::Block* target, int pnum) {
1502 if (TraceOptoParse) {
1503 tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1504 }
1505
1506 // Zap extra stack slots to top
1507 assert(sp() == target->start_sp(), "");
1508 clean_stack(sp());
1509
1510 if (!target->is_merged()) { // No prior mapping at this bci
1511 if (TraceOptoParse) { tty->print(" with empty state"); }
1512
1513 // If this path is dead, do not bother capturing it as a merge.
1514 // It is "as if" we had 1 fewer predecessors from the beginning.
1515 if (stopped()) {
1516 if (TraceOptoParse) tty->print_cr(", but path is dead and doesn't count");
1517 return;
1518 }
1519
1520 // Record that a new block has been merged.
1521 ++_blocks_merged;
1522
1523 // Make a region if we know there are multiple or unpredictable inputs.
1524 // (Also, if this is a plain fall-through, we might see another region,
1525 // which must not be allowed into this block's map.)
1526 if (pnum > PhiNode::Input // Known multiple inputs.
1527 || target->is_handler() // These have unpredictable inputs.
1528 || target->is_loop_head() // Known multiple inputs
1529 || control()->is_Region()) { // We must hide this guy.
1530 // Add a Region to start the new basic block. Phis will be added
1531 // later lazily.
1532 int edges = target->pred_count();
1533 if (edges < pnum) edges = pnum; // might be a new path!
1534 Node *r = new (C, edges+1) RegionNode(edges+1);
1535 gvn().set_type(r, Type::CONTROL);
1536 record_for_igvn(r);
1537 // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1538 // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1539 r->init_req(pnum, control());
1540 set_control(r);
1541 }
1542
1543 // Convert the existing Parser mapping into a mapping at this bci.
1544 store_state_to(target);
1545 assert(target->is_merged(), "do not come here twice");
1546
1547 } else { // Prior mapping at this bci
1548 if (TraceOptoParse) { tty->print(" with previous state"); }
1549
1550 // We must not manufacture more phis if the target is already parsed.
1551 bool nophi = target->is_parsed();
1552
1553 SafePointNode* newin = map();// Hang on to incoming mapping
1554 Block* save_block = block(); // Hang on to incoming block;
1555 load_state_from(target); // Get prior mapping
1556
1557 assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1558 assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1559 assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1560 assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1561
1562 // Iterate over my current mapping and the old mapping.
1563 // Where different, insert Phi functions.
1564 // Use any existing Phi functions.
1565 assert(control()->is_Region(), "must be merging to a region");
1566 RegionNode* r = control()->as_Region();
1567
1568 // Compute where to merge into
1569 // Merge incoming control path
1570 r->init_req(pnum, newin->control());
1571
1572 if (pnum == 1) { // Last merge for this Region?
1573 if (!block()->flow()->is_irreducible_entry()) {
1574 Node* result = _gvn.transform_no_reclaim(r);
1575 if (r != result && TraceOptoParse) {
1576 tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1577 }
1578 }
1579 record_for_igvn(r);
1580 }
1581
1582 // Update all the non-control inputs to map:
1583 assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1584 bool check_elide_phi = target->is_SEL_backedge(save_block);
1585 for (uint j = 1; j < newin->req(); j++) {
1586 Node* m = map()->in(j); // Current state of target.
1587 Node* n = newin->in(j); // Incoming change to target state.
1588 PhiNode* phi;
1589 if (m->is_Phi() && m->as_Phi()->region() == r)
1590 phi = m->as_Phi();
1591 else
1592 phi = NULL;
1593 if (m != n) { // Different; must merge
1594 switch (j) {
1595 // Frame pointer and Return Address never changes
1596 case TypeFunc::FramePtr:// Drop m, use the original value
1597 case TypeFunc::ReturnAdr:
1598 break;
1599 case TypeFunc::Memory: // Merge inputs to the MergeMem node
1600 assert(phi == NULL, "the merge contains phis, not vice versa");
1601 merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1602 continue;
1603 default: // All normal stuff
1604 if (phi == NULL) {
1605 if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1606 phi = ensure_phi(j, nophi);
1607 }
1608 }
1609 break;
1610 }
1611 }
1612 // At this point, n might be top if:
1613 // - there is no phi (because TypeFlow detected a conflict), or
1614 // - the corresponding control edges is top (a dead incoming path)
1615 // It is a bug if we create a phi which sees a garbage value on a live path.
1616
1617 if (phi != NULL) {
1618 assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1619 assert(phi->region() == r, "");
1620 phi->set_req(pnum, n); // Then add 'n' to the merge
1621 if (pnum == PhiNode::Input) {
1622 // Last merge for this Phi.
1623 // So far, Phis have had a reasonable type from ciTypeFlow.
1624 // Now _gvn will join that with the meet of current inputs.
1625 // BOTTOM is never permissible here, 'cause pessimistically
1626 // Phis of pointers cannot lose the basic pointer type.
1627 debug_only(const Type* bt1 = phi->bottom_type());
1628 assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1629 map()->set_req(j, _gvn.transform_no_reclaim(phi));
1630 debug_only(const Type* bt2 = phi->bottom_type());
1631 assert(bt2->higher_equal(bt1), "must be consistent with type-flow");
1632 record_for_igvn(phi);
1633 }
1634 }
1635 } // End of for all values to be merged
1636
1637 if (pnum == PhiNode::Input &&
1638 !r->in(0)) { // The occasional useless Region
1639 assert(control() == r, "");
1640 set_control(r->nonnull_req());
1641 }
1642
1643 // newin has been subsumed into the lazy merge, and is now dead.
1644 set_block(save_block);
1645
1646 stop(); // done with this guy, for now
1647 }
1648
1649 if (TraceOptoParse) {
1650 tty->print_cr(" on path %d", pnum);
1651 }
1652
1653 // Done with this parser state.
1654 assert(stopped(), "");
1655 }
1656
1657
1658 //--------------------------merge_memory_edges---------------------------------
1659 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1660 // (nophi means we must not create phis, because we already parsed here)
1661 assert(n != NULL, "");
1662 // Merge the inputs to the MergeMems
1663 MergeMemNode* m = merged_memory();
1664
1665 assert(control()->is_Region(), "must be merging to a region");
1666 RegionNode* r = control()->as_Region();
1667
1668 PhiNode* base = NULL;
1669 MergeMemNode* remerge = NULL;
1670 for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1671 Node *p = mms.force_memory();
1672 Node *q = mms.memory2();
1673 if (mms.is_empty() && nophi) {
1674 // Trouble: No new splits allowed after a loop body is parsed.
1675 // Instead, wire the new split into a MergeMem on the backedge.
1676 // The optimizer will sort it out, slicing the phi.
1677 if (remerge == NULL) {
1678 assert(base != NULL, "");
1679 assert(base->in(0) != NULL, "should not be xformed away");
1680 remerge = MergeMemNode::make(C, base->in(pnum));
1681 gvn().set_type(remerge, Type::MEMORY);
1682 base->set_req(pnum, remerge);
1683 }
1684 remerge->set_memory_at(mms.alias_idx(), q);
1685 continue;
1686 }
1687 assert(!q->is_MergeMem(), "");
1688 PhiNode* phi;
1689 if (p != q) {
1690 phi = ensure_memory_phi(mms.alias_idx(), nophi);
1691 } else {
1692 if (p->is_Phi() && p->as_Phi()->region() == r)
1693 phi = p->as_Phi();
1694 else
1695 phi = NULL;
1696 }
1697 // Insert q into local phi
1698 if (phi != NULL) {
1699 assert(phi->region() == r, "");
1700 p = phi;
1701 phi->set_req(pnum, q);
1702 if (mms.at_base_memory()) {
1703 base = phi; // delay transforming it
1704 } else if (pnum == 1) {
1705 record_for_igvn(phi);
1706 p = _gvn.transform_no_reclaim(phi);
1707 }
1708 mms.set_memory(p);// store back through the iterator
1709 }
1710 }
1711 // Transform base last, in case we must fiddle with remerging.
1712 if (base != NULL && pnum == 1) {
1713 record_for_igvn(base);
1714 m->set_base_memory( _gvn.transform_no_reclaim(base) );
1715 }
1716 }
1717
1718
1719 //------------------------ensure_phis_everywhere-------------------------------
1720 void Parse::ensure_phis_everywhere() {
1721 ensure_phi(TypeFunc::I_O);
1722
1723 // Ensure a phi on all currently known memories.
1724 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
1725 ensure_memory_phi(mms.alias_idx());
1726 debug_only(mms.set_memory()); // keep the iterator happy
1727 }
1728
1729 // Note: This is our only chance to create phis for memory slices.
1730 // If we miss a slice that crops up later, it will have to be
1731 // merged into the base-memory phi that we are building here.
1732 // Later, the optimizer will comb out the knot, and build separate
1733 // phi-loops for each memory slice that matters.
1734
1735 // Monitors must nest nicely and not get confused amongst themselves.
1736 // Phi-ify everything up to the monitors, though.
1737 uint monoff = map()->jvms()->monoff();
1738 uint nof_monitors = map()->jvms()->nof_monitors();
1739
1740 assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
1741 bool check_elide_phi = block()->is_SEL_head();
1742 for (uint i = TypeFunc::Parms; i < monoff; i++) {
1743 if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
1744 ensure_phi(i);
1745 }
1746 }
1747
1748 // Even monitors need Phis, though they are well-structured.
1749 // This is true for OSR methods, and also for the rare cases where
1750 // a monitor object is the subject of a replace_in_map operation.
1751 // See bugs 4426707 and 5043395.
1752 for (uint m = 0; m < nof_monitors; m++) {
1753 ensure_phi(map()->jvms()->monitor_obj_offset(m));
1754 }
1755 }
1756
1757
1758 //-----------------------------add_new_path------------------------------------
1759 // Add a previously unaccounted predecessor to this block.
1760 int Parse::Block::add_new_path() {
1761 // If there is no map, return the lowest unused path number.
1762 if (!is_merged()) return pred_count()+1; // there will be a map shortly
1763
1764 SafePointNode* map = start_map();
1765 if (!map->control()->is_Region())
1766 return pred_count()+1; // there may be a region some day
1767 RegionNode* r = map->control()->as_Region();
1768
1769 // Add new path to the region.
1770 uint pnum = r->req();
1771 r->add_req(NULL);
1772
1773 for (uint i = 1; i < map->req(); i++) {
1774 Node* n = map->in(i);
1775 if (i == TypeFunc::Memory) {
1776 // Ensure a phi on all currently known memories.
1777 for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1778 Node* phi = mms.memory();
1779 if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1780 assert(phi->req() == pnum, "must be same size as region");
1781 phi->add_req(NULL);
1782 }
1783 }
1784 } else {
1785 if (n->is_Phi() && n->as_Phi()->region() == r) {
1786 assert(n->req() == pnum, "must be same size as region");
1787 n->add_req(NULL);
1788 }
1789 }
1790 }
1791
1792 return pnum;
1793 }
1794
1795 //------------------------------ensure_phi-------------------------------------
1796 // Turn the idx'th entry of the current map into a Phi
1797 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
1798 SafePointNode* map = this->map();
1799 Node* region = map->control();
1800 assert(region->is_Region(), "");
1801
1802 Node* o = map->in(idx);
1803 assert(o != NULL, "");
1804
1805 if (o == top()) return NULL; // TOP always merges into TOP
1806
1807 if (o->is_Phi() && o->as_Phi()->region() == region) {
1808 return o->as_Phi();
1809 }
1810
1811 // Now use a Phi here for merging
1812 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1813 const JVMState* jvms = map->jvms();
1814 const Type* t;
1815 if (jvms->is_loc(idx)) {
1816 t = block()->local_type_at(idx - jvms->locoff());
1817 } else if (jvms->is_stk(idx)) {
1818 t = block()->stack_type_at(idx - jvms->stkoff());
1819 } else if (jvms->is_mon(idx)) {
1820 assert(!jvms->is_monitor_box(idx), "no phis for boxes");
1821 t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
1822 } else if ((uint)idx < TypeFunc::Parms) {
1823 t = o->bottom_type(); // Type::RETURN_ADDRESS or such-like.
1824 } else {
1825 assert(false, "no type information for this phi");
1826 }
1827
1828 // If the type falls to bottom, then this must be a local that
1829 // is mixing ints and oops or some such. Forcing it to top
1830 // makes it go dead.
1831 if (t == Type::BOTTOM) {
1832 map->set_req(idx, top());
1833 return NULL;
1834 }
1835
1836 // Do not create phis for top either.
1837 // A top on a non-null control flow must be an unused even after the.phi.
1838 if (t == Type::TOP || t == Type::HALF) {
1839 map->set_req(idx, top());
1840 return NULL;
1841 }
1842
1843 PhiNode* phi = PhiNode::make(region, o, t);
1844 gvn().set_type(phi, t);
1845 if (C->do_escape_analysis()) record_for_igvn(phi);
1846 map->set_req(idx, phi);
1847 return phi;
1848 }
1849
1850 //--------------------------ensure_memory_phi----------------------------------
1851 // Turn the idx'th slice of the current memory into a Phi
1852 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
1853 MergeMemNode* mem = merged_memory();
1854 Node* region = control();
1855 assert(region->is_Region(), "");
1856
1857 Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
1858 assert(o != NULL && o != top(), "");
1859
1860 PhiNode* phi;
1861 if (o->is_Phi() && o->as_Phi()->region() == region) {
1862 phi = o->as_Phi();
1863 if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
1864 // clone the shared base memory phi to make a new memory split
1865 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1866 const Type* t = phi->bottom_type();
1867 const TypePtr* adr_type = C->get_adr_type(idx);
1868 phi = phi->slice_memory(adr_type);
1869 gvn().set_type(phi, t);
1870 }
1871 return phi;
1872 }
1873
1874 // Now use a Phi here for merging
1875 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1876 const Type* t = o->bottom_type();
1877 const TypePtr* adr_type = C->get_adr_type(idx);
1878 phi = PhiNode::make(region, o, t, adr_type);
1879 gvn().set_type(phi, t);
1880 if (idx == Compile::AliasIdxBot)
1881 mem->set_base_memory(phi);
1882 else
1883 mem->set_memory_at(idx, phi);
1884 return phi;
1885 }
1886
1887 //------------------------------call_register_finalizer-----------------------
1888 // Check the klass of the receiver and call register_finalizer if the
1889 // class need finalization.
1890 void Parse::call_register_finalizer() {
1891 Node* receiver = local(0);
1892 assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
1893 "must have non-null instance type");
1894
1895 const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
1896 if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
1897 // The type isn't known exactly so see if CHA tells us anything.
1898 ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
1899 if (!Dependencies::has_finalizable_subclass(ik)) {
1900 // No finalizable subclasses so skip the dynamic check.
1901 C->dependencies()->assert_has_no_finalizable_subclasses(ik);
1902 return;
1903 }
1904 }
1905
1906 // Insert a dynamic test for whether the instance needs
1907 // finalization. In general this will fold up since the concrete
1908 // class is often visible so the access flags are constant.
1909 Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
1910 Node* klass = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), klass_addr, TypeInstPtr::KLASS) );
1911
1912 Node* access_flags_addr = basic_plus_adr(klass, klass, Klass::access_flags_offset_in_bytes() + sizeof(oopDesc));
1913 Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT);
1914
1915 Node* mask = _gvn.transform(new (C, 3) AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
1916 Node* check = _gvn.transform(new (C, 3) CmpINode(mask, intcon(0)));
1917 Node* test = _gvn.transform(new (C, 2) BoolNode(check, BoolTest::ne));
1918
1919 IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
1920
1921 RegionNode* result_rgn = new (C, 3) RegionNode(3);
1922 record_for_igvn(result_rgn);
1923
1924 Node *skip_register = _gvn.transform(new (C, 1) IfFalseNode(iff));
1925 result_rgn->init_req(1, skip_register);
1926
1927 Node *needs_register = _gvn.transform(new (C, 1) IfTrueNode(iff));
1928 set_control(needs_register);
1929 if (stopped()) {
1930 // There is no slow path.
1931 result_rgn->init_req(2, top());
1932 } else {
1933 Node *call = make_runtime_call(RC_NO_LEAF,
1934 OptoRuntime::register_finalizer_Type(),
1935 OptoRuntime::register_finalizer_Java(),
1936 NULL, TypePtr::BOTTOM,
1937 receiver);
1938 make_slow_call_ex(call, env()->Throwable_klass(), true);
1939
1940 Node* fast_io = call->in(TypeFunc::I_O);
1941 Node* fast_mem = call->in(TypeFunc::Memory);
1942 // These two phis are pre-filled with copies of of the fast IO and Memory
1943 Node* io_phi = PhiNode::make(result_rgn, fast_io, Type::ABIO);
1944 Node* mem_phi = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
1945
1946 result_rgn->init_req(2, control());
1947 io_phi ->init_req(2, i_o());
1948 mem_phi ->init_req(2, reset_memory());
1949
1950 set_all_memory( _gvn.transform(mem_phi) );
1951 set_i_o( _gvn.transform(io_phi) );
1952 }
1953
1954 set_control( _gvn.transform(result_rgn) );
1955 }
1956
1957 //------------------------------return_current---------------------------------
1958 // Append current _map to _exit_return
1959 void Parse::return_current(Node* value) {
1960 if (RegisterFinalizersAtInit &&
1961 method()->intrinsic_id() == vmIntrinsics::_Object_init) {
1962 call_register_finalizer();
1963 }
1964
1965 // Do not set_parse_bci, so that return goo is credited to the return insn.
1966 set_bci(InvocationEntryBci);
1967 if (method()->is_synchronized() && GenerateSynchronizationCode) {
1968 shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
1969 }
1970 if (C->env()->dtrace_method_probes()) {
1971 make_dtrace_method_exit(method());
1972 }
1973 SafePointNode* exit_return = _exits.map();
1974 exit_return->in( TypeFunc::Control )->add_req( control() );
1975 exit_return->in( TypeFunc::I_O )->add_req( i_o () );
1976 Node *mem = exit_return->in( TypeFunc::Memory );
1977 for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
1978 if (mms.is_empty()) {
1979 // get a copy of the base memory, and patch just this one input
1980 const TypePtr* adr_type = mms.adr_type(C);
1981 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
1982 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
1983 gvn().set_type_bottom(phi);
1984 phi->del_req(phi->req()-1); // prepare to re-patch
1985 mms.set_memory(phi);
1986 }
1987 mms.memory()->add_req(mms.memory2());
1988 }
1989
1990 // frame pointer is always same, already captured
1991 if (value != NULL) {
1992 // If returning oops to an interface-return, there is a silent free
1993 // cast from oop to interface allowed by the Verifier. Make it explicit
1994 // here.
1995 Node* phi = _exits.argument(0);
1996 const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
1997 if( tr && tr->klass()->is_loaded() &&
1998 tr->klass()->is_interface() ) {
1999 const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
2000 if (tp && tp->klass()->is_loaded() &&
2001 !tp->klass()->is_interface()) {
2002 // sharpen the type eagerly; this eases certain assert checking
2003 if (tp->higher_equal(TypeInstPtr::NOTNULL))
2004 tr = tr->join(TypeInstPtr::NOTNULL)->is_instptr();
2005 value = _gvn.transform(new (C, 2) CheckCastPPNode(0,value,tr));
2006 }
2007 }
2008 phi->add_req(value);
2009 }
2010
2011 stop_and_kill_map(); // This CFG path dies here
2012 }
2013
2014
2015 //------------------------------add_safepoint----------------------------------
2016 void Parse::add_safepoint() {
2017 // See if we can avoid this safepoint. No need for a SafePoint immediately
2018 // after a Call (except Leaf Call) or another SafePoint.
2019 Node *proj = control();
2020 bool add_poll_param = SafePointNode::needs_polling_address_input();
2021 uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2022 if( proj->is_Proj() ) {
2023 Node *n0 = proj->in(0);
2024 if( n0->is_Catch() ) {
2025 n0 = n0->in(0)->in(0);
2026 assert( n0->is_Call(), "expect a call here" );
2027 }
2028 if( n0->is_Call() ) {
2029 if( n0->as_Call()->guaranteed_safepoint() )
2030 return;
2031 } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2032 return;
2033 }
2034 }
2035
2036 // Clear out dead values from the debug info.
2037 kill_dead_locals();
2038
2039 // Clone the JVM State
2040 SafePointNode *sfpnt = new (C, parms) SafePointNode(parms, NULL);
2041
2042 // Capture memory state BEFORE a SafePoint. Since we can block at a
2043 // SafePoint we need our GC state to be safe; i.e. we need all our current
2044 // write barriers (card marks) to not float down after the SafePoint so we
2045 // must read raw memory. Likewise we need all oop stores to match the card
2046 // marks. If deopt can happen, we need ALL stores (we need the correct JVM
2047 // state on a deopt).
2048
2049 // We do not need to WRITE the memory state after a SafePoint. The control
2050 // edge will keep card-marks and oop-stores from floating up from below a
2051 // SafePoint and our true dependency added here will keep them from floating
2052 // down below a SafePoint.
2053
2054 // Clone the current memory state
2055 Node* mem = MergeMemNode::make(C, map()->memory());
2056
2057 mem = _gvn.transform(mem);
2058
2059 // Pass control through the safepoint
2060 sfpnt->init_req(TypeFunc::Control , control());
2061 // Fix edges normally used by a call
2062 sfpnt->init_req(TypeFunc::I_O , top() );
2063 sfpnt->init_req(TypeFunc::Memory , mem );
2064 sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2065 sfpnt->init_req(TypeFunc::FramePtr , top() );
2066
2067 // Create a node for the polling address
2068 if( add_poll_param ) {
2069 Node *polladr = ConPNode::make(C, (address)os::get_polling_page());
2070 sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2071 }
2072
2073 // Fix up the JVM State edges
2074 add_safepoint_edges(sfpnt);
2075 Node *transformed_sfpnt = _gvn.transform(sfpnt);
2076 set_control(transformed_sfpnt);
2077
2078 // Provide an edge from root to safepoint. This makes the safepoint
2079 // appear useful until the parse has completed.
2080 if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2081 assert(C->root() != NULL, "Expect parse is still valid");
2082 C->root()->add_prec(transformed_sfpnt);
2083 }
2084 }
2085
2086 #ifndef PRODUCT
2087 //------------------------show_parse_info--------------------------------------
2088 void Parse::show_parse_info() {
2089 InlineTree* ilt = NULL;
2090 if (C->ilt() != NULL) {
2091 JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2092 ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2093 }
2094 if (PrintCompilation && Verbose) {
2095 if (depth() == 1) {
2096 if( ilt->count_inlines() ) {
2097 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2098 ilt->count_inline_bcs());
2099 tty->cr();
2100 }
2101 } else {
2102 if (method()->is_synchronized()) tty->print("s");
2103 if (method()->has_exception_handlers()) tty->print("!");
2104 // Check this is not the final compiled version
2105 if (C->trap_can_recompile()) {
2106 tty->print("-");
2107 } else {
2108 tty->print(" ");
2109 }
2110 method()->print_short_name();
2111 if (is_osr_parse()) {
2112 tty->print(" @ %d", osr_bci());
2113 }
2114 tty->print(" (%d bytes)",method()->code_size());
2115 if (ilt->count_inlines()) {
2116 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2117 ilt->count_inline_bcs());
2118 }
2119 tty->cr();
2120 }
2121 }
2122 if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2123 // Print that we succeeded; suppress this message on the first osr parse.
2124
2125 if (method()->is_synchronized()) tty->print("s");
2126 if (method()->has_exception_handlers()) tty->print("!");
2127 // Check this is not the final compiled version
2128 if (C->trap_can_recompile() && depth() == 1) {
2129 tty->print("-");
2130 } else {
2131 tty->print(" ");
2132 }
2133 if( depth() != 1 ) { tty->print(" "); } // missing compile count
2134 for (int i = 1; i < depth(); ++i) { tty->print(" "); }
2135 method()->print_short_name();
2136 if (is_osr_parse()) {
2137 tty->print(" @ %d", osr_bci());
2138 }
2139 if (ilt->caller_bci() != -1) {
2140 tty->print(" @ %d", ilt->caller_bci());
2141 }
2142 tty->print(" (%d bytes)",method()->code_size());
2143 if (ilt->count_inlines()) {
2144 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2145 ilt->count_inline_bcs());
2146 }
2147 tty->cr();
2148 }
2149 }
2150
2151
2152 //------------------------------dump-------------------------------------------
2153 // Dump information associated with the bytecodes of current _method
2154 void Parse::dump() {
2155 if( method() != NULL ) {
2156 // Iterate over bytecodes
2157 ciBytecodeStream iter(method());
2158 for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2159 dump_bci( iter.cur_bci() );
2160 tty->cr();
2161 }
2162 }
2163 }
2164
2165 // Dump information associated with a byte code index, 'bci'
2166 void Parse::dump_bci(int bci) {
2167 // Output info on merge-points, cloning, and within _jsr..._ret
2168 // NYI
2169 tty->print(" bci:%d", bci);
2170 }
2171
2172 #endif