1 /*
2 * Copyright (c) 1997, 2016, 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 */
24
25 #include "precompiled.hpp"
26 #include "compiler/compileLog.hpp"
27 #include "interpreter/linkResolver.hpp"
28 #include "oops/methodOop.hpp"
29 #include "opto/addnode.hpp"
30 #include "opto/idealGraphPrinter.hpp"
31 #include "opto/locknode.hpp"
32 #include "opto/memnode.hpp"
33 #include "opto/parse.hpp"
34 #include "opto/rootnode.hpp"
35 #include "opto/runtime.hpp"
36 #include "runtime/arguments.hpp"
37 #include "runtime/handles.inline.hpp"
38 #include "runtime/sharedRuntime.hpp"
39 #include "utilities/copy.hpp"
40
41 // Static array so we can figure out which bytecodes stop us from compiling
42 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
43 // and eventually should be encapsulated in a proper class (gri 8/18/98).
44
45 int nodes_created = 0;
46 int methods_parsed = 0;
47 int methods_seen = 0;
48 int blocks_parsed = 0;
49 int blocks_seen = 0;
50
51 int explicit_null_checks_inserted = 0;
52 int explicit_null_checks_elided = 0;
53 int all_null_checks_found = 0, implicit_null_checks = 0;
54 int implicit_null_throws = 0;
55
56 int reclaim_idx = 0;
57 int reclaim_in = 0;
58 int reclaim_node = 0;
59
60 #ifndef PRODUCT
61 bool Parse::BytecodeParseHistogram::_initialized = false;
62 uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
63 uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
64 uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
65 uint Parse::BytecodeParseHistogram::_new_values [Bytecodes::number_of_codes];
66 #endif
67
68 //------------------------------print_statistics-------------------------------
69 #ifndef PRODUCT
70 void Parse::print_statistics() {
71 tty->print_cr("--- Compiler Statistics ---");
72 tty->print("Methods seen: %d Methods parsed: %d", methods_seen, methods_parsed);
73 tty->print(" Nodes created: %d", nodes_created);
74 tty->cr();
75 if (methods_seen != methods_parsed)
76 tty->print_cr("Reasons for parse failures (NOT cumulative):");
77 tty->print_cr("Blocks parsed: %d Blocks seen: %d", blocks_parsed, blocks_seen);
78
79 if( explicit_null_checks_inserted )
80 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);
81 if( all_null_checks_found )
82 tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
83 (100*implicit_null_checks)/all_null_checks_found);
84 if( implicit_null_throws )
85 tty->print_cr("%d implicit null exceptions at runtime",
86 implicit_null_throws);
87
88 if( PrintParseStatistics && BytecodeParseHistogram::initialized() ) {
89 BytecodeParseHistogram::print();
90 }
91 }
92 #endif
93
94 //------------------------------ON STACK REPLACEMENT---------------------------
95
96 // Construct a node which can be used to get incoming state for
97 // on stack replacement.
98 Node *Parse::fetch_interpreter_state(int index,
99 BasicType bt,
100 Node *local_addrs,
101 Node *local_addrs_base) {
102 Node *mem = memory(Compile::AliasIdxRaw);
103 Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
104 Node *ctl = control();
105
106 // Very similar to LoadNode::make, except we handle un-aligned longs and
107 // doubles on Sparc. Intel can handle them just fine directly.
108 Node *l;
109 switch( bt ) { // Signature is flattened
110 case T_INT: l = new (C) LoadINode( ctl, mem, adr, TypeRawPtr::BOTTOM ); break;
111 case T_FLOAT: l = new (C) LoadFNode( ctl, mem, adr, TypeRawPtr::BOTTOM ); break;
112 case T_ADDRESS: l = new (C) LoadPNode( ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM ); break;
113 case T_OBJECT: l = new (C) LoadPNode( ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM ); break;
114 case T_LONG:
115 case T_DOUBLE: {
116 // Since arguments are in reverse order, the argument address 'adr'
117 // refers to the back half of the long/double. Recompute adr.
118 adr = basic_plus_adr( local_addrs_base, local_addrs, -(index+1)*wordSize );
119 if( Matcher::misaligned_doubles_ok ) {
120 l = (bt == T_DOUBLE)
121 ? (Node*)new (C) LoadDNode( ctl, mem, adr, TypeRawPtr::BOTTOM )
122 : (Node*)new (C) LoadLNode( ctl, mem, adr, TypeRawPtr::BOTTOM );
123 } else {
124 l = (bt == T_DOUBLE)
125 ? (Node*)new (C) LoadD_unalignedNode( ctl, mem, adr, TypeRawPtr::BOTTOM )
126 : (Node*)new (C) LoadL_unalignedNode( ctl, mem, adr, TypeRawPtr::BOTTOM );
127 }
128 break;
129 }
130 default: ShouldNotReachHere();
131 }
132 return _gvn.transform(l);
133 }
134
135 // Helper routine to prevent the interpreter from handing
136 // unexpected typestate to an OSR method.
137 // The Node l is a value newly dug out of the interpreter frame.
138 // The type is the type predicted by ciTypeFlow. Note that it is
139 // not a general type, but can only come from Type::get_typeflow_type.
140 // The safepoint is a map which will feed an uncommon trap.
141 Node* Parse::check_interpreter_type(Node* l, const Type* type,
142 SafePointNode* &bad_type_exit) {
143
144 const TypeOopPtr* tp = type->isa_oopptr();
145
146 // TypeFlow may assert null-ness if a type appears unloaded.
147 if (type == TypePtr::NULL_PTR ||
148 (tp != NULL && !tp->klass()->is_loaded())) {
149 // Value must be null, not a real oop.
150 Node* chk = _gvn.transform( new (C) CmpPNode(l, null()) );
151 Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
152 IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
153 set_control(_gvn.transform( new (C) IfTrueNode(iff) ));
154 Node* bad_type = _gvn.transform( new (C) IfFalseNode(iff) );
155 bad_type_exit->control()->add_req(bad_type);
156 l = null();
157 }
158
159 // Typeflow can also cut off paths from the CFG, based on
160 // types which appear unloaded, or call sites which appear unlinked.
161 // When paths are cut off, values at later merge points can rise
162 // toward more specific classes. Make sure these specific classes
163 // are still in effect.
164 if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
165 // TypeFlow asserted a specific object type. Value must have that type.
166 Node* bad_type_ctrl = NULL;
167 l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
168 bad_type_exit->control()->add_req(bad_type_ctrl);
169 }
170
171 BasicType bt_l = _gvn.type(l)->basic_type();
172 BasicType bt_t = type->basic_type();
173 assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
174 return l;
175 }
176
177 // Helper routine which sets up elements of the initial parser map when
178 // performing a parse for on stack replacement. Add values into map.
179 // The only parameter contains the address of a interpreter arguments.
180 void Parse::load_interpreter_state(Node* osr_buf) {
181 int index;
182 int max_locals = jvms()->loc_size();
183 int max_stack = jvms()->stk_size();
184
185
186 // Mismatch between method and jvms can occur since map briefly held
187 // an OSR entry state (which takes up one RawPtr word).
188 assert(max_locals == method()->max_locals(), "sanity");
189 assert(max_stack >= method()->max_stack(), "sanity");
190 assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
191 assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
192
193 // Find the start block.
194 Block* osr_block = start_block();
195 assert(osr_block->start() == osr_bci(), "sanity");
196
197 // Set initial BCI.
198 set_parse_bci(osr_block->start());
199
200 // Set initial stack depth.
201 set_sp(osr_block->start_sp());
202
203 // Check bailouts. We currently do not perform on stack replacement
204 // of loops in catch blocks or loops which branch with a non-empty stack.
205 if (sp() != 0) {
206 C->record_method_not_compilable("OSR starts with non-empty stack");
207 return;
208 }
209 // Do not OSR inside finally clauses:
210 if (osr_block->has_trap_at(osr_block->start())) {
211 C->record_method_not_compilable("OSR starts with an immediate trap");
212 return;
213 }
214
215 // Commute monitors from interpreter frame to compiler frame.
216 assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
217 int mcnt = osr_block->flow()->monitor_count();
218 Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
219 for (index = 0; index < mcnt; index++) {
220 // Make a BoxLockNode for the monitor.
221 Node *box = _gvn.transform(new (C) BoxLockNode(next_monitor()));
222
223
224 // Displaced headers and locked objects are interleaved in the
225 // temp OSR buffer. We only copy the locked objects out here.
226 // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
227 Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
228 // Try and copy the displaced header to the BoxNode
229 Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);
230
231
232 store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw);
233
234 // Build a bogus FastLockNode (no code will be generated) and push the
235 // monitor into our debug info.
236 const FastLockNode *flock = _gvn.transform(new (C) FastLockNode( 0, lock_object, box ))->as_FastLock();
237 map()->push_monitor(flock);
238
239 // If the lock is our method synchronization lock, tuck it away in
240 // _sync_lock for return and rethrow exit paths.
241 if (index == 0 && method()->is_synchronized()) {
242 _synch_lock = flock;
243 }
244 }
245
246 // Use the raw liveness computation to make sure that unexpected
247 // values don't propagate into the OSR frame.
248 MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
249 if (!live_locals.is_valid()) {
250 // Degenerate or breakpointed method.
251 C->record_method_not_compilable("OSR in empty or breakpointed method");
252 return;
253 }
254
255 // Extract the needed locals from the interpreter frame.
256 Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);
257
258 // find all the locals that the interpreter thinks contain live oops
259 const BitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
260 for (index = 0; index < max_locals; index++) {
261
262 if (!live_locals.at(index)) {
263 continue;
264 }
265
266 const Type *type = osr_block->local_type_at(index);
267
268 if (type->isa_oopptr() != NULL) {
269
270 // 6403625: Verify that the interpreter oopMap thinks that the oop is live
271 // else we might load a stale oop if the MethodLiveness disagrees with the
272 // result of the interpreter. If the interpreter says it is dead we agree
273 // by making the value go to top.
274 //
275
276 if (!live_oops.at(index)) {
277 if (C->log() != NULL) {
278 C->log()->elem("OSR_mismatch local_index='%d'",index);
279 }
280 set_local(index, null());
281 // and ignore it for the loads
282 continue;
283 }
284 }
285
286 // Filter out TOP, HALF, and BOTTOM. (Cf. ensure_phi.)
287 if (type == Type::TOP || type == Type::HALF) {
288 continue;
289 }
290 // If the type falls to bottom, then this must be a local that
291 // is mixing ints and oops or some such. Forcing it to top
292 // makes it go dead.
293 if (type == Type::BOTTOM) {
294 continue;
295 }
296 // Construct code to access the appropriate local.
297 BasicType bt = type->basic_type();
298 if (type == TypePtr::NULL_PTR) {
299 // Ptr types are mixed together with T_ADDRESS but NULL is
300 // really for T_OBJECT types so correct it.
301 bt = T_OBJECT;
302 }
303 Node *value = fetch_interpreter_state(index, bt, locals_addr, osr_buf);
304 set_local(index, value);
305 }
306
307 // Extract the needed stack entries from the interpreter frame.
308 for (index = 0; index < sp(); index++) {
309 const Type *type = osr_block->stack_type_at(index);
310 if (type != Type::TOP) {
311 // Currently the compiler bails out when attempting to on stack replace
312 // at a bci with a non-empty stack. We should not reach here.
313 ShouldNotReachHere();
314 }
315 }
316
317 // End the OSR migration
318 make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
319 CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
320 "OSR_migration_end", TypeRawPtr::BOTTOM,
321 osr_buf);
322
323 // Now that the interpreter state is loaded, make sure it will match
324 // at execution time what the compiler is expecting now:
325 SafePointNode* bad_type_exit = clone_map();
326 bad_type_exit->set_control(new (C) RegionNode(1));
327
328 assert(osr_block->flow()->jsrs()->size() == 0, "should be no jsrs live at osr point");
329 for (index = 0; index < max_locals; index++) {
330 if (stopped()) break;
331 Node* l = local(index);
332 if (l->is_top()) continue; // nothing here
333 const Type *type = osr_block->local_type_at(index);
334 if (type->isa_oopptr() != NULL) {
335 if (!live_oops.at(index)) {
336 // skip type check for dead oops
337 continue;
338 }
339 }
340 if (osr_block->flow()->local_type_at(index)->is_return_address()) {
341 // In our current system it's illegal for jsr addresses to be
342 // live into an OSR entry point because the compiler performs
343 // inlining of jsrs. ciTypeFlow has a bailout that detect this
344 // case and aborts the compile if addresses are live into an OSR
345 // entry point. Because of that we can assume that any address
346 // locals at the OSR entry point are dead. Method liveness
347 // isn't precise enought to figure out that they are dead in all
348 // cases so simply skip checking address locals all
349 // together. Any type check is guaranteed to fail since the
350 // interpreter type is the result of a load which might have any
351 // value and the expected type is a constant.
352 continue;
353 }
354 set_local(index, check_interpreter_type(l, type, bad_type_exit));
355 }
356
357 for (index = 0; index < sp(); index++) {
358 if (stopped()) break;
359 Node* l = stack(index);
360 if (l->is_top()) continue; // nothing here
361 const Type *type = osr_block->stack_type_at(index);
362 set_stack(index, check_interpreter_type(l, type, bad_type_exit));
363 }
364
365 if (bad_type_exit->control()->req() > 1) {
366 // Build an uncommon trap here, if any inputs can be unexpected.
367 bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
368 record_for_igvn(bad_type_exit->control());
369 SafePointNode* types_are_good = map();
370 set_map(bad_type_exit);
371 // The unexpected type happens because a new edge is active
372 // in the CFG, which typeflow had previously ignored.
373 // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
374 // This x will be typed as Integer if notReached is not yet linked.
375 // It could also happen due to a problem in ciTypeFlow analysis.
376 uncommon_trap(Deoptimization::Reason_constraint,
377 Deoptimization::Action_reinterpret);
378 set_map(types_are_good);
379 }
380 }
381
382 //------------------------------Parse------------------------------------------
383 // Main parser constructor.
384 Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses)
385 : _exits(caller)
386 {
387 // Init some variables
388 _caller = caller;
389 _method = parse_method;
390 _expected_uses = expected_uses;
391 _depth = 1 + (caller->has_method() ? caller->depth() : 0);
392 _wrote_final = false;
393 // Add MemBarRelease for constructors which write volatile field (PPC64).
394 PPC64_ONLY(_wrote_volatile = false;)
395 _entry_bci = InvocationEntryBci;
396 _tf = NULL;
397 _block = NULL;
398 _first_return = true;
399 _replaced_nodes_for_exceptions = false;
400 _new_idx = C->unique();
401 debug_only(_block_count = -1);
402 debug_only(_blocks = (Block*)-1);
403 #ifndef PRODUCT
404 if (PrintCompilation || PrintOpto) {
405 // Make sure I have an inline tree, so I can print messages about it.
406 JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
407 InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method);
408 }
409 _max_switch_depth = 0;
410 _est_switch_depth = 0;
411 #endif
412
413 _tf = TypeFunc::make(method());
414 _iter.reset_to_method(method());
415 _flow = method()->get_flow_analysis();
416 if (_flow->failing()) {
417 C->record_method_not_compilable_all_tiers(_flow->failure_reason());
418 }
419
420 #ifndef PRODUCT
421 if (_flow->has_irreducible_entry()) {
422 C->set_parsed_irreducible_loop(true);
423 }
424 #endif
425
426 if (_expected_uses <= 0) {
427 _prof_factor = 1;
428 } else {
429 float prof_total = parse_method->interpreter_invocation_count();
430 if (prof_total <= _expected_uses) {
431 _prof_factor = 1;
432 } else {
433 _prof_factor = _expected_uses / prof_total;
434 }
435 }
436
437 CompileLog* log = C->log();
438 if (log != NULL) {
439 log->begin_head("parse method='%d' uses='%g'",
440 log->identify(parse_method), expected_uses);
441 if (depth() == 1 && C->is_osr_compilation()) {
442 log->print(" osr_bci='%d'", C->entry_bci());
443 }
444 log->stamp();
445 log->end_head();
446 }
447
448 // Accumulate deoptimization counts.
449 // (The range_check and store_check counts are checked elsewhere.)
450 ciMethodData* md = method()->method_data();
451 for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
452 uint md_count = md->trap_count(reason);
453 if (md_count != 0) {
454 if (md_count == md->trap_count_limit())
455 md_count += md->overflow_trap_count();
456 uint total_count = C->trap_count(reason);
457 uint old_count = total_count;
458 total_count += md_count;
459 // Saturate the add if it overflows.
460 if (total_count < old_count || total_count < md_count)
461 total_count = (uint)-1;
462 C->set_trap_count(reason, total_count);
463 if (log != NULL)
464 log->elem("observe trap='%s' count='%d' total='%d'",
465 Deoptimization::trap_reason_name(reason),
466 md_count, total_count);
467 }
468 }
469 // Accumulate total sum of decompilations, also.
470 C->set_decompile_count(C->decompile_count() + md->decompile_count());
471
472 _count_invocations = C->do_count_invocations();
473 _method_data_update = C->do_method_data_update();
474
475 if (log != NULL && method()->has_exception_handlers()) {
476 log->elem("observe that='has_exception_handlers'");
477 }
478
479 assert(method()->can_be_compiled(), "Can not parse this method, cutout earlier");
480 assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
481
482 // Always register dependence if JVMTI is enabled, because
483 // either breakpoint setting or hotswapping of methods may
484 // cause deoptimization.
485 if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
486 C->dependencies()->assert_evol_method(method());
487 }
488
489 methods_seen++;
490
491 // Do some special top-level things.
492 if (depth() == 1 && C->is_osr_compilation()) {
493 _entry_bci = C->entry_bci();
494 _flow = method()->get_osr_flow_analysis(osr_bci());
495 if (_flow->failing()) {
496 C->record_method_not_compilable(_flow->failure_reason());
497 #ifndef PRODUCT
498 if (PrintOpto && (Verbose || WizardMode)) {
499 tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
500 if (Verbose) {
501 method()->print_oop();
502 method()->print_codes();
503 _flow->print();
504 }
505 }
506 #endif
507 }
508 _tf = C->tf(); // the OSR entry type is different
509 }
510
511 #ifdef ASSERT
512 if (depth() == 1) {
513 assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
514 if (C->tf() != tf()) {
515 MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
516 assert(C->env()->system_dictionary_modification_counter_changed(),
517 "Must invalidate if TypeFuncs differ");
518 }
519 } else {
520 assert(!this->is_osr_parse(), "no recursive OSR");
521 }
522 #endif
523
524 methods_parsed++;
525 #ifndef PRODUCT
526 // add method size here to guarantee that inlined methods are added too
527 if (TimeCompiler)
528 _total_bytes_compiled += method()->code_size();
529
530 show_parse_info();
531 #endif
532
533 if (failing()) {
534 if (log) log->done("parse");
535 return;
536 }
537
538 gvn().set_type(root(), root()->bottom_type());
539 gvn().transform(top());
540
541 // Import the results of the ciTypeFlow.
542 init_blocks();
543
544 // Merge point for all normal exits
545 build_exits();
546
547 // Setup the initial JVM state map.
548 SafePointNode* entry_map = create_entry_map();
549
550 // Check for bailouts during map initialization
551 if (failing() || entry_map == NULL) {
552 if (log) log->done("parse");
553 return;
554 }
555
556 Node_Notes* caller_nn = C->default_node_notes();
557 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
558 if (DebugInlinedCalls || depth() == 1) {
559 C->set_default_node_notes(make_node_notes(caller_nn));
560 }
561
562 if (is_osr_parse()) {
563 Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
564 entry_map->set_req(TypeFunc::Parms+0, top());
565 set_map(entry_map);
566 load_interpreter_state(osr_buf);
567 } else {
568 set_map(entry_map);
569 do_method_entry();
570 }
571
572 // Check for bailouts during method entry.
573 if (failing()) {
574 if (log) log->done("parse");
575 C->set_default_node_notes(caller_nn);
576 return;
577 }
578
579 entry_map = map(); // capture any changes performed by method setup code
580 assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
581
582 // We begin parsing as if we have just encountered a jump to the
583 // method entry.
584 Block* entry_block = start_block();
585 assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
586 set_map_clone(entry_map);
587 merge_common(entry_block, entry_block->next_path_num());
588
589 #ifndef PRODUCT
590 BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
591 set_parse_histogram( parse_histogram_obj );
592 #endif
593
594 // Parse all the basic blocks.
595 do_all_blocks();
596
597 C->set_default_node_notes(caller_nn);
598
599 // Check for bailouts during conversion to graph
600 if (failing()) {
601 if (log) log->done("parse");
602 return;
603 }
604
605 // Fix up all exiting control flow.
606 set_map(entry_map);
607 do_exits();
608
609 if (log) log->done("parse nodes='%d' live='%d' memory='%d'",
610 C->unique(), C->live_nodes(), C->node_arena()->used());
611 }
612
613 //---------------------------do_all_blocks-------------------------------------
614 void Parse::do_all_blocks() {
615 bool has_irreducible = flow()->has_irreducible_entry();
616
617 // Walk over all blocks in Reverse Post-Order.
618 while (true) {
619 bool progress = false;
620 for (int rpo = 0; rpo < block_count(); rpo++) {
621 Block* block = rpo_at(rpo);
622
623 if (block->is_parsed()) continue;
624
625 if (!block->is_merged()) {
626 // Dead block, no state reaches this block
627 continue;
628 }
629
630 // Prepare to parse this block.
631 load_state_from(block);
632
633 if (stopped()) {
634 // Block is dead.
635 continue;
636 }
637
638 blocks_parsed++;
639
640 progress = true;
641 if (block->is_loop_head() || block->is_handler() || has_irreducible && !block->is_ready()) {
642 // Not all preds have been parsed. We must build phis everywhere.
643 // (Note that dead locals do not get phis built, ever.)
644 ensure_phis_everywhere();
645
646 if (block->is_SEL_head() &&
647 (UseLoopPredicate || LoopLimitCheck)) {
648 // Add predicate to single entry (not irreducible) loop head.
649 assert(!block->has_merged_backedge(), "only entry paths should be merged for now");
650 // Need correct bci for predicate.
651 // It is fine to set it here since do_one_block() will set it anyway.
652 set_parse_bci(block->start());
653 add_predicate();
654 // Add new region for back branches.
655 int edges = block->pred_count() - block->preds_parsed() + 1; // +1 for original region
656 RegionNode *r = new (C) RegionNode(edges+1);
657 _gvn.set_type(r, Type::CONTROL);
658 record_for_igvn(r);
659 r->init_req(edges, control());
660 set_control(r);
661 // Add new phis.
662 ensure_phis_everywhere();
663 }
664
665 // Leave behind an undisturbed copy of the map, for future merges.
666 set_map(clone_map());
667 }
668
669 if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
670 // In the absence of irreducible loops, the Region and Phis
671 // associated with a merge that doesn't involve a backedge can
672 // be simplified now since the RPO parsing order guarantees
673 // that any path which was supposed to reach here has already
674 // been parsed or must be dead.
675 Node* c = control();
676 Node* result = _gvn.transform_no_reclaim(control());
677 if (c != result && TraceOptoParse) {
678 tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
679 }
680 if (result != top()) {
681 record_for_igvn(result);
682 }
683 }
684
685 // Parse the block.
686 do_one_block();
687
688 // Check for bailouts.
689 if (failing()) return;
690 }
691
692 // with irreducible loops multiple passes might be necessary to parse everything
693 if (!has_irreducible || !progress) {
694 break;
695 }
696 }
697
698 blocks_seen += block_count();
699
700 #ifndef PRODUCT
701 // Make sure there are no half-processed blocks remaining.
702 // Every remaining unprocessed block is dead and may be ignored now.
703 for (int rpo = 0; rpo < block_count(); rpo++) {
704 Block* block = rpo_at(rpo);
705 if (!block->is_parsed()) {
706 if (TraceOptoParse) {
707 tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
708 }
709 assert(!block->is_merged(), "no half-processed blocks");
710 }
711 }
712 #endif
713 }
714
715 static Node* mask_int_value(Node* v, BasicType bt, PhaseGVN* gvn) {
716 Compile* C = gvn->C;
717 switch (bt) {
718 case T_BYTE:
719 v = gvn->transform(new (C) LShiftINode(v, gvn->intcon(24)));
720 v = gvn->transform(new (C) RShiftINode(v, gvn->intcon(24)));
721 break;
722 case T_SHORT:
723 v = gvn->transform(new (C) LShiftINode(v, gvn->intcon(16)));
724 v = gvn->transform(new (C) RShiftINode(v, gvn->intcon(16)));
725 break;
726 case T_CHAR:
727 v = gvn->transform(new (C) AndINode(v, gvn->intcon(0xFFFF)));
728 break;
729 case T_BOOLEAN:
730 v = gvn->transform(new (C) AndINode(v, gvn->intcon(0x1)));
731 break;
732 }
733 return v;
734 }
735
736 //-------------------------------build_exits----------------------------------
737 // Build normal and exceptional exit merge points.
738 void Parse::build_exits() {
739 // make a clone of caller to prevent sharing of side-effects
740 _exits.set_map(_exits.clone_map());
741 _exits.clean_stack(_exits.sp());
742 _exits.sync_jvms();
743
744 RegionNode* region = new (C) RegionNode(1);
745 record_for_igvn(region);
746 gvn().set_type_bottom(region);
747 _exits.set_control(region);
748
749 // Note: iophi and memphi are not transformed until do_exits.
750 Node* iophi = new (C) PhiNode(region, Type::ABIO);
751 Node* memphi = new (C) PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
752 _exits.set_i_o(iophi);
753 _exits.set_all_memory(memphi);
754
755 // Add a return value to the exit state. (Do not push it yet.)
756 if (tf()->range()->cnt() > TypeFunc::Parms) {
757 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
758 if (ret_type->isa_int()) {
759 BasicType ret_bt = method()->return_type()->basic_type();
760 if (ret_bt == T_BOOLEAN ||
761 ret_bt == T_CHAR ||
762 ret_bt == T_BYTE ||
763 ret_bt == T_SHORT) {
764 ret_type = TypeInt::INT;
765 }
766 }
767
768 // Don't "bind" an unloaded return klass to the ret_phi. If the klass
769 // becomes loaded during the subsequent parsing, the loaded and unloaded
770 // types will not join when we transform and push in do_exits().
771 const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
772 if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
773 ret_type = TypeOopPtr::BOTTOM;
774 }
775 int ret_size = type2size[ret_type->basic_type()];
776 Node* ret_phi = new (C) PhiNode(region, ret_type);
777 _exits.ensure_stack(ret_size);
778 assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
779 assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
780 _exits.set_argument(0, ret_phi); // here is where the parser finds it
781 // Note: ret_phi is not yet pushed, until do_exits.
782 }
783 }
784
785
786 //----------------------------build_start_state-------------------------------
787 // Construct a state which contains only the incoming arguments from an
788 // unknown caller. The method & bci will be NULL & InvocationEntryBci.
789 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
790 int arg_size = tf->domain()->cnt();
791 int max_size = MAX2(arg_size, (int)tf->range()->cnt());
792 JVMState* jvms = new (this) JVMState(max_size - TypeFunc::Parms);
793 SafePointNode* map = new (this) SafePointNode(max_size, NULL);
794 record_for_igvn(map);
795 assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
796 Node_Notes* old_nn = default_node_notes();
797 if (old_nn != NULL && has_method()) {
798 Node_Notes* entry_nn = old_nn->clone(this);
799 JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
800 entry_jvms->set_offsets(0);
801 entry_jvms->set_bci(entry_bci());
802 entry_nn->set_jvms(entry_jvms);
803 set_default_node_notes(entry_nn);
804 }
805 uint i;
806 for (i = 0; i < (uint)arg_size; i++) {
807 Node* parm = initial_gvn()->transform(new (this) ParmNode(start, i));
808 map->init_req(i, parm);
809 // Record all these guys for later GVN.
810 record_for_igvn(parm);
811 }
812 for (; i < map->req(); i++) {
813 map->init_req(i, top());
814 }
815 assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
816 set_default_node_notes(old_nn);
817 map->set_jvms(jvms);
818 jvms->set_map(map);
819 return jvms;
820 }
821
822 //-----------------------------make_node_notes---------------------------------
823 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
824 if (caller_nn == NULL) return NULL;
825 Node_Notes* nn = caller_nn->clone(C);
826 JVMState* caller_jvms = nn->jvms();
827 JVMState* jvms = new (C) JVMState(method(), caller_jvms);
828 jvms->set_offsets(0);
829 jvms->set_bci(_entry_bci);
830 nn->set_jvms(jvms);
831 return nn;
832 }
833
834
835 //--------------------------return_values--------------------------------------
836 void Compile::return_values(JVMState* jvms) {
837 GraphKit kit(jvms);
838 Node* ret = new (this) ReturnNode(TypeFunc::Parms,
839 kit.control(),
840 kit.i_o(),
841 kit.reset_memory(),
842 kit.frameptr(),
843 kit.returnadr());
844 // Add zero or 1 return values
845 int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
846 if (ret_size > 0) {
847 kit.inc_sp(-ret_size); // pop the return value(s)
848 kit.sync_jvms();
849 ret->add_req(kit.argument(0));
850 // Note: The second dummy edge is not needed by a ReturnNode.
851 }
852 // bind it to root
853 root()->add_req(ret);
854 record_for_igvn(ret);
855 initial_gvn()->transform_no_reclaim(ret);
856 }
857
858 //------------------------rethrow_exceptions-----------------------------------
859 // Bind all exception states in the list into a single RethrowNode.
860 void Compile::rethrow_exceptions(JVMState* jvms) {
861 GraphKit kit(jvms);
862 if (!kit.has_exceptions()) return; // nothing to generate
863 // Load my combined exception state into the kit, with all phis transformed:
864 SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
865 Node* ex_oop = kit.use_exception_state(ex_map);
866 RethrowNode* exit = new (this) RethrowNode(kit.control(),
867 kit.i_o(), kit.reset_memory(),
868 kit.frameptr(), kit.returnadr(),
869 // like a return but with exception input
870 ex_oop);
871 // bind to root
872 root()->add_req(exit);
873 record_for_igvn(exit);
874 initial_gvn()->transform_no_reclaim(exit);
875 }
876
877 //---------------------------do_exceptions-------------------------------------
878 // Process exceptions arising from the current bytecode.
879 // Send caught exceptions to the proper handler within this method.
880 // Unhandled exceptions feed into _exit.
881 void Parse::do_exceptions() {
882 if (!has_exceptions()) return;
883
884 if (failing()) {
885 // Pop them all off and throw them away.
886 while (pop_exception_state() != NULL) ;
887 return;
888 }
889
890 PreserveJVMState pjvms(this, false);
891
892 SafePointNode* ex_map;
893 while ((ex_map = pop_exception_state()) != NULL) {
894 if (!method()->has_exception_handlers()) {
895 // Common case: Transfer control outward.
896 // Doing it this early allows the exceptions to common up
897 // even between adjacent method calls.
898 throw_to_exit(ex_map);
899 } else {
900 // Have to look at the exception first.
901 assert(stopped(), "catch_inline_exceptions trashes the map");
902 catch_inline_exceptions(ex_map);
903 stop_and_kill_map(); // we used up this exception state; kill it
904 }
905 }
906
907 // We now return to our regularly scheduled program:
908 }
909
910 //---------------------------throw_to_exit-------------------------------------
911 // Merge the given map into an exception exit from this method.
912 // The exception exit will handle any unlocking of receiver.
913 // The ex_oop must be saved within the ex_map, unlike merge_exception.
914 void Parse::throw_to_exit(SafePointNode* ex_map) {
915 // Pop the JVMS to (a copy of) the caller.
916 GraphKit caller;
917 caller.set_map_clone(_caller->map());
918 caller.set_bci(_caller->bci());
919 caller.set_sp(_caller->sp());
920 // Copy out the standard machine state:
921 for (uint i = 0; i < TypeFunc::Parms; i++) {
922 caller.map()->set_req(i, ex_map->in(i));
923 }
924 if (ex_map->has_replaced_nodes()) {
925 _replaced_nodes_for_exceptions = true;
926 }
927 caller.map()->transfer_replaced_nodes_from(ex_map, _new_idx);
928 // ...and the exception:
929 Node* ex_oop = saved_ex_oop(ex_map);
930 SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
931 // Finally, collect the new exception state in my exits:
932 _exits.add_exception_state(caller_ex_map);
933 }
934
935 //------------------------------do_exits---------------------------------------
936 void Parse::do_exits() {
937 set_parse_bci(InvocationEntryBci);
938
939 // Now peephole on the return bits
940 Node* region = _exits.control();
941 _exits.set_control(gvn().transform(region));
942
943 Node* iophi = _exits.i_o();
944 _exits.set_i_o(gvn().transform(iophi));
945
946 // Add MemBarRelease for constructors which write volatile field (PPC64).
947 // Intention is to avoid that other threads can observe initial values even though the
948 // constructor has set the volatile field. Java programmers wouldn't like it and we wanna be nice.
949 if (wrote_final() PPC64_ONLY(|| (wrote_volatile() && method()->is_initializer()))) {
950 // This method (which must be a constructor by the rules of Java)
951 // wrote a final. The effects of all initializations must be
952 // committed to memory before any code after the constructor
953 // publishes the reference to the newly constructor object.
954 // Rather than wait for the publication, we simply block the
955 // writes here. Rather than put a barrier on only those writes
956 // which are required to complete, we force all writes to complete.
957 //
958 // "All bets are off" unless the first publication occurs after a
959 // normal return from the constructor. We do not attempt to detect
960 // such unusual early publications. But no barrier is needed on
961 // exceptional returns, since they cannot publish normally.
962 //
963 _exits.insert_mem_bar(Op_MemBarRelease);
964 #ifndef PRODUCT
965 if (PrintOpto && (Verbose || WizardMode)) {
966 method()->print_name();
967 tty->print_cr(" writes finals and needs a memory barrier");
968 }
969 #endif
970 }
971
972 for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
973 // transform each slice of the original memphi:
974 mms.set_memory(_gvn.transform(mms.memory()));
975 }
976
977 if (tf()->range()->cnt() > TypeFunc::Parms) {
978 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
979 Node* ret_phi = _gvn.transform( _exits.argument(0) );
980 assert(_exits.control()->is_top() || !_gvn.type(ret_phi)->empty(), "return value must be well defined");
981 if (ret_type->isa_int()) {
982 BasicType ret_bt = method()->return_type()->basic_type();
983 ret_phi = mask_int_value(ret_phi, ret_bt, &_gvn);
984 }
985 _exits.push_node(ret_type->basic_type(), ret_phi);
986 }
987
988 // Note: Logic for creating and optimizing the ReturnNode is in Compile.
989
990 // Unlock along the exceptional paths.
991 // This is done late so that we can common up equivalent exceptions
992 // (e.g., null checks) arising from multiple points within this method.
993 // See GraphKit::add_exception_state, which performs the commoning.
994 bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
995
996 // record exit from a method if compiled while Dtrace is turned on.
997 if (do_synch || C->env()->dtrace_method_probes() || _replaced_nodes_for_exceptions) {
998 // First move the exception list out of _exits:
999 GraphKit kit(_exits.transfer_exceptions_into_jvms());
1000 SafePointNode* normal_map = kit.map(); // keep this guy safe
1001 // Now re-collect the exceptions into _exits:
1002 SafePointNode* ex_map;
1003 while ((ex_map = kit.pop_exception_state()) != NULL) {
1004 Node* ex_oop = kit.use_exception_state(ex_map);
1005 // Force the exiting JVM state to have this method at InvocationEntryBci.
1006 // The exiting JVM state is otherwise a copy of the calling JVMS.
1007 JVMState* caller = kit.jvms();
1008 JVMState* ex_jvms = caller->clone_shallow(C);
1009 ex_jvms->set_map(kit.clone_map());
1010 ex_jvms->map()->set_jvms(ex_jvms);
1011 ex_jvms->set_bci( InvocationEntryBci);
1012 kit.set_jvms(ex_jvms);
1013 if (do_synch) {
1014 // Add on the synchronized-method box/object combo
1015 kit.map()->push_monitor(_synch_lock);
1016 // Unlock!
1017 kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
1018 }
1019 if (C->env()->dtrace_method_probes()) {
1020 kit.make_dtrace_method_exit(method());
1021 }
1022 if (_replaced_nodes_for_exceptions) {
1023 kit.map()->apply_replaced_nodes(_new_idx);
1024 }
1025 // Done with exception-path processing.
1026 ex_map = kit.make_exception_state(ex_oop);
1027 assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
1028 // Pop the last vestige of this method:
1029 ex_map->set_jvms(caller->clone_shallow(C));
1030 ex_map->jvms()->set_map(ex_map);
1031 _exits.push_exception_state(ex_map);
1032 }
1033 assert(_exits.map() == normal_map, "keep the same return state");
1034 }
1035
1036 {
1037 // Capture very early exceptions (receiver null checks) from caller JVMS
1038 GraphKit caller(_caller);
1039 SafePointNode* ex_map;
1040 while ((ex_map = caller.pop_exception_state()) != NULL) {
1041 _exits.add_exception_state(ex_map);
1042 }
1043 }
1044 _exits.map()->apply_replaced_nodes(_new_idx);
1045 }
1046
1047 //-----------------------------create_entry_map-------------------------------
1048 // Initialize our parser map to contain the types at method entry.
1049 // For OSR, the map contains a single RawPtr parameter.
1050 // Initial monitor locking for sync. methods is performed by do_method_entry.
1051 SafePointNode* Parse::create_entry_map() {
1052 // Check for really stupid bail-out cases.
1053 uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1054 if (len >= 32760) {
1055 C->record_method_not_compilable_all_tiers("too many local variables");
1056 return NULL;
1057 }
1058
1059 // clear current replaced nodes that are of no use from here on (map was cloned in build_exits).
1060 _caller->map()->delete_replaced_nodes();
1061
1062 // If this is an inlined method, we may have to do a receiver null check.
1063 if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1064 GraphKit kit(_caller);
1065 kit.null_check_receiver_before_call(method());
1066 _caller = kit.transfer_exceptions_into_jvms();
1067 if (kit.stopped()) {
1068 _exits.add_exception_states_from(_caller);
1069 _exits.set_jvms(_caller);
1070 return NULL;
1071 }
1072 }
1073
1074 assert(method() != NULL, "parser must have a method");
1075
1076 // Create an initial safepoint to hold JVM state during parsing
1077 JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1078 set_map(new (C) SafePointNode(len, jvms));
1079 jvms->set_map(map());
1080 record_for_igvn(map());
1081 assert(jvms->endoff() == len, "correct jvms sizing");
1082
1083 SafePointNode* inmap = _caller->map();
1084 assert(inmap != NULL, "must have inmap");
1085 // In case of null check on receiver above
1086 map()->transfer_replaced_nodes_from(inmap, _new_idx);
1087
1088 uint i;
1089
1090 // Pass thru the predefined input parameters.
1091 for (i = 0; i < TypeFunc::Parms; i++) {
1092 map()->init_req(i, inmap->in(i));
1093 }
1094
1095 if (depth() == 1) {
1096 assert(map()->memory()->Opcode() == Op_Parm, "");
1097 // Insert the memory aliasing node
1098 set_all_memory(reset_memory());
1099 }
1100 assert(merged_memory(), "");
1101
1102 // Now add the locals which are initially bound to arguments:
1103 uint arg_size = tf()->domain()->cnt();
1104 ensure_stack(arg_size - TypeFunc::Parms); // OSR methods have funny args
1105 for (i = TypeFunc::Parms; i < arg_size; i++) {
1106 map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1107 }
1108
1109 // Clear out the rest of the map (locals and stack)
1110 for (i = arg_size; i < len; i++) {
1111 map()->init_req(i, top());
1112 }
1113
1114 SafePointNode* entry_map = stop();
1115 return entry_map;
1116 }
1117
1118 //-----------------------------do_method_entry--------------------------------
1119 // Emit any code needed in the pseudo-block before BCI zero.
1120 // The main thing to do is lock the receiver of a synchronized method.
1121 void Parse::do_method_entry() {
1122 set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1123 set_sp(0); // Java Stack Pointer
1124
1125 NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1126
1127 if (C->env()->dtrace_method_probes()) {
1128 make_dtrace_method_entry(method());
1129 }
1130
1131 // If the method is synchronized, we need to construct a lock node, attach
1132 // it to the Start node, and pin it there.
1133 if (method()->is_synchronized()) {
1134 // Insert a FastLockNode right after the Start which takes as arguments
1135 // the current thread pointer, the "this" pointer & the address of the
1136 // stack slot pair used for the lock. The "this" pointer is a projection
1137 // off the start node, but the locking spot has to be constructed by
1138 // creating a ConLNode of 0, and boxing it with a BoxLockNode. The BoxLockNode
1139 // becomes the second argument to the FastLockNode call. The
1140 // FastLockNode becomes the new control parent to pin it to the start.
1141
1142 // Setup Object Pointer
1143 Node *lock_obj = NULL;
1144 if(method()->is_static()) {
1145 ciInstance* mirror = _method->holder()->java_mirror();
1146 const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1147 lock_obj = makecon(t_lock);
1148 } else { // Else pass the "this" pointer,
1149 lock_obj = local(0); // which is Parm0 from StartNode
1150 }
1151 // Clear out dead values from the debug info.
1152 kill_dead_locals();
1153 // Build the FastLockNode
1154 _synch_lock = shared_lock(lock_obj);
1155 }
1156
1157 if (depth() == 1) {
1158 increment_and_test_invocation_counter(Tier2CompileThreshold);
1159 }
1160 }
1161
1162 //------------------------------init_blocks------------------------------------
1163 // Initialize our parser map to contain the types/monitors at method entry.
1164 void Parse::init_blocks() {
1165 // Create the blocks.
1166 _block_count = flow()->block_count();
1167 _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
1168 Copy::zero_to_bytes(_blocks, sizeof(Block)*_block_count);
1169
1170 int rpo;
1171
1172 // Initialize the structs.
1173 for (rpo = 0; rpo < block_count(); rpo++) {
1174 Block* block = rpo_at(rpo);
1175 block->init_node(this, rpo);
1176 }
1177
1178 // Collect predecessor and successor information.
1179 for (rpo = 0; rpo < block_count(); rpo++) {
1180 Block* block = rpo_at(rpo);
1181 block->init_graph(this);
1182 }
1183 }
1184
1185 //-------------------------------init_node-------------------------------------
1186 void Parse::Block::init_node(Parse* outer, int rpo) {
1187 _flow = outer->flow()->rpo_at(rpo);
1188 _pred_count = 0;
1189 _preds_parsed = 0;
1190 _count = 0;
1191 assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
1192 assert(!(is_merged() || is_parsed() || is_handler() || has_merged_backedge()), "sanity");
1193 assert(_live_locals.size() == 0, "sanity");
1194
1195 // entry point has additional predecessor
1196 if (flow()->is_start()) _pred_count++;
1197 assert(flow()->is_start() == (this == outer->start_block()), "");
1198 }
1199
1200 //-------------------------------init_graph------------------------------------
1201 void Parse::Block::init_graph(Parse* outer) {
1202 // Create the successor list for this parser block.
1203 GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
1204 GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
1205 int ns = tfs->length();
1206 int ne = tfe->length();
1207 _num_successors = ns;
1208 _all_successors = ns+ne;
1209 _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
1210 int p = 0;
1211 for (int i = 0; i < ns+ne; i++) {
1212 ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
1213 Block* block2 = outer->rpo_at(tf2->rpo());
1214 _successors[i] = block2;
1215
1216 // Accumulate pred info for the other block, too.
1217 if (i < ns) {
1218 block2->_pred_count++;
1219 } else {
1220 block2->_is_handler = true;
1221 }
1222
1223 #ifdef ASSERT
1224 // A block's successors must be distinguishable by BCI.
1225 // That is, no bytecode is allowed to branch to two different
1226 // clones of the same code location.
1227 for (int j = 0; j < i; j++) {
1228 Block* block1 = _successors[j];
1229 if (block1 == block2) continue; // duplicates are OK
1230 assert(block1->start() != block2->start(), "successors have unique bcis");
1231 }
1232 #endif
1233 }
1234
1235 // Note: We never call next_path_num along exception paths, so they
1236 // never get processed as "ready". Also, the input phis of exception
1237 // handlers get specially processed, so that
1238 }
1239
1240 //---------------------------successor_for_bci---------------------------------
1241 Parse::Block* Parse::Block::successor_for_bci(int bci) {
1242 for (int i = 0; i < all_successors(); i++) {
1243 Block* block2 = successor_at(i);
1244 if (block2->start() == bci) return block2;
1245 }
1246 // We can actually reach here if ciTypeFlow traps out a block
1247 // due to an unloaded class, and concurrently with compilation the
1248 // class is then loaded, so that a later phase of the parser is
1249 // able to see more of the bytecode CFG. Or, the flow pass and
1250 // the parser can have a minor difference of opinion about executability
1251 // of bytecodes. For example, "obj.field = null" is executable even
1252 // if the field's type is an unloaded class; the flow pass used to
1253 // make a trap for such code.
1254 return NULL;
1255 }
1256
1257
1258 //-----------------------------stack_type_at-----------------------------------
1259 const Type* Parse::Block::stack_type_at(int i) const {
1260 return get_type(flow()->stack_type_at(i));
1261 }
1262
1263
1264 //-----------------------------local_type_at-----------------------------------
1265 const Type* Parse::Block::local_type_at(int i) const {
1266 // Make dead locals fall to bottom.
1267 if (_live_locals.size() == 0) {
1268 MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
1269 // This bitmap can be zero length if we saw a breakpoint.
1270 // In such cases, pretend they are all live.
1271 ((Block*)this)->_live_locals = live_locals;
1272 }
1273 if (_live_locals.size() > 0 && !_live_locals.at(i))
1274 return Type::BOTTOM;
1275
1276 return get_type(flow()->local_type_at(i));
1277 }
1278
1279
1280 #ifndef PRODUCT
1281
1282 //----------------------------name_for_bc--------------------------------------
1283 // helper method for BytecodeParseHistogram
1284 static const char* name_for_bc(int i) {
1285 return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
1286 }
1287
1288 //----------------------------BytecodeParseHistogram------------------------------------
1289 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
1290 _parser = p;
1291 _compiler = c;
1292 if( ! _initialized ) { _initialized = true; reset(); }
1293 }
1294
1295 //----------------------------current_count------------------------------------
1296 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
1297 switch( bph_type ) {
1298 case BPH_transforms: { return _parser->gvn().made_progress(); }
1299 case BPH_values: { return _parser->gvn().made_new_values(); }
1300 default: { ShouldNotReachHere(); return 0; }
1301 }
1302 }
1303
1304 //----------------------------initialized--------------------------------------
1305 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
1306
1307 //----------------------------reset--------------------------------------------
1308 void Parse::BytecodeParseHistogram::reset() {
1309 int i = Bytecodes::number_of_codes;
1310 while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
1311 }
1312
1313 //----------------------------set_initial_state--------------------------------
1314 // Record info when starting to parse one bytecode
1315 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
1316 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1317 _initial_bytecode = bc;
1318 _initial_node_count = _compiler->unique();
1319 _initial_transforms = current_count(BPH_transforms);
1320 _initial_values = current_count(BPH_values);
1321 }
1322 }
1323
1324 //----------------------------record_change--------------------------------
1325 // Record results of parsing one bytecode
1326 void Parse::BytecodeParseHistogram::record_change() {
1327 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1328 ++_bytecodes_parsed[_initial_bytecode];
1329 _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
1330 _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
1331 _new_values [_initial_bytecode] += (current_count(BPH_values) - _initial_values);
1332 }
1333 }
1334
1335
1336 //----------------------------print--------------------------------------------
1337 void Parse::BytecodeParseHistogram::print(float cutoff) {
1338 ResourceMark rm;
1339 // print profile
1340 int total = 0;
1341 int i = 0;
1342 for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
1343 int abs_sum = 0;
1344 tty->cr(); //0123456789012345678901234567890123456789012345678901234567890123456789
1345 tty->print_cr("Histogram of %d parsed bytecodes:", total);
1346 if( total == 0 ) { return; }
1347 tty->cr();
1348 tty->print_cr("absolute: count of compiled bytecodes of this type");
1349 tty->print_cr("relative: percentage contribution to compiled nodes");
1350 tty->print_cr("nodes : Average number of nodes constructed per bytecode");
1351 tty->print_cr("rnodes : Significance towards total nodes constructed, (nodes*relative)");
1352 tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
1353 tty->print_cr("values : Average number of node values improved per bytecode");
1354 tty->print_cr("name : Bytecode name");
1355 tty->cr();
1356 tty->print_cr(" absolute relative nodes rnodes transforms values name");
1357 tty->print_cr("----------------------------------------------------------------------");
1358 while (--i > 0) {
1359 int abs = _bytecodes_parsed[i];
1360 float rel = abs * 100.0F / total;
1361 float nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
1362 float rnodes = _bytecodes_parsed[i] == 0 ? 0 : rel * nodes;
1363 float xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
1364 float values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values [i])/_bytecodes_parsed[i];
1365 if (cutoff <= rel) {
1366 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));
1367 abs_sum += abs;
1368 }
1369 }
1370 tty->print_cr("----------------------------------------------------------------------");
1371 float rel_sum = abs_sum * 100.0F / total;
1372 tty->print_cr("%10d %7.2f%% (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
1373 tty->print_cr("----------------------------------------------------------------------");
1374 tty->cr();
1375 }
1376 #endif
1377
1378 //----------------------------load_state_from----------------------------------
1379 // Load block/map/sp. But not do not touch iter/bci.
1380 void Parse::load_state_from(Block* block) {
1381 set_block(block);
1382 // load the block's JVM state:
1383 set_map(block->start_map());
1384 set_sp( block->start_sp());
1385 }
1386
1387
1388 //-----------------------------record_state------------------------------------
1389 void Parse::Block::record_state(Parse* p) {
1390 assert(!is_merged(), "can only record state once, on 1st inflow");
1391 assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
1392 set_start_map(p->stop());
1393 }
1394
1395
1396 //------------------------------do_one_block-----------------------------------
1397 void Parse::do_one_block() {
1398 if (TraceOptoParse) {
1399 Block *b = block();
1400 int ns = b->num_successors();
1401 int nt = b->all_successors();
1402
1403 tty->print("Parsing block #%d at bci [%d,%d), successors: ",
1404 block()->rpo(), block()->start(), block()->limit());
1405 for (int i = 0; i < nt; i++) {
1406 tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
1407 }
1408 if (b->is_loop_head()) tty->print(" lphd");
1409 tty->print_cr("");
1410 }
1411
1412 assert(block()->is_merged(), "must be merged before being parsed");
1413 block()->mark_parsed();
1414 ++_blocks_parsed;
1415
1416 // Set iterator to start of block.
1417 iter().reset_to_bci(block()->start());
1418
1419 CompileLog* log = C->log();
1420
1421 // Parse bytecodes
1422 while (!stopped() && !failing()) {
1423 iter().next();
1424
1425 // Learn the current bci from the iterator:
1426 set_parse_bci(iter().cur_bci());
1427
1428 if (bci() == block()->limit()) {
1429 // Do not walk into the next block until directed by do_all_blocks.
1430 merge(bci());
1431 break;
1432 }
1433 assert(bci() < block()->limit(), "bci still in block");
1434
1435 if (log != NULL) {
1436 // Output an optional context marker, to help place actions
1437 // that occur during parsing of this BC. If there is no log
1438 // output until the next context string, this context string
1439 // will be silently ignored.
1440 log->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
1441 }
1442
1443 if (block()->has_trap_at(bci())) {
1444 // We must respect the flow pass's traps, because it will refuse
1445 // to produce successors for trapping blocks.
1446 int trap_index = block()->flow()->trap_index();
1447 assert(trap_index != 0, "trap index must be valid");
1448 uncommon_trap(trap_index);
1449 break;
1450 }
1451
1452 NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1453
1454 #ifdef ASSERT
1455 int pre_bc_sp = sp();
1456 int inputs, depth;
1457 bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1458 assert(!have_se || pre_bc_sp >= inputs, err_msg_res("have enough stack to execute this BC: pre_bc_sp=%d, inputs=%d", pre_bc_sp, inputs));
1459 #endif //ASSERT
1460
1461 do_one_bytecode();
1462
1463 assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
1464 err_msg_res("incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth));
1465
1466 do_exceptions();
1467
1468 NOT_PRODUCT( parse_histogram()->record_change(); );
1469
1470 if (log != NULL)
1471 log->clear_context(); // skip marker if nothing was printed
1472
1473 // Fall into next bytecode. Each bytecode normally has 1 sequential
1474 // successor which is typically made ready by visiting this bytecode.
1475 // If the successor has several predecessors, then it is a merge
1476 // point, starts a new basic block, and is handled like other basic blocks.
1477 }
1478 }
1479
1480
1481 //------------------------------merge------------------------------------------
1482 void Parse::set_parse_bci(int bci) {
1483 set_bci(bci);
1484 Node_Notes* nn = C->default_node_notes();
1485 if (nn == NULL) return;
1486
1487 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
1488 if (!DebugInlinedCalls && depth() > 1) {
1489 return;
1490 }
1491
1492 // Update the JVMS annotation, if present.
1493 JVMState* jvms = nn->jvms();
1494 if (jvms != NULL && jvms->bci() != bci) {
1495 // Update the JVMS.
1496 jvms = jvms->clone_shallow(C);
1497 jvms->set_bci(bci);
1498 nn->set_jvms(jvms);
1499 }
1500 }
1501
1502 //------------------------------merge------------------------------------------
1503 // Merge the current mapping into the basic block starting at bci
1504 void Parse::merge(int target_bci) {
1505 Block* target = successor_for_bci(target_bci);
1506 if (target == NULL) { handle_missing_successor(target_bci); return; }
1507 assert(!target->is_ready(), "our arrival must be expected");
1508 int pnum = target->next_path_num();
1509 merge_common(target, pnum);
1510 }
1511
1512 //-------------------------merge_new_path--------------------------------------
1513 // Merge the current mapping into the basic block, using a new path
1514 void Parse::merge_new_path(int target_bci) {
1515 Block* target = successor_for_bci(target_bci);
1516 if (target == NULL) { handle_missing_successor(target_bci); return; }
1517 assert(!target->is_ready(), "new path into frozen graph");
1518 int pnum = target->add_new_path();
1519 merge_common(target, pnum);
1520 }
1521
1522 //-------------------------merge_exception-------------------------------------
1523 // Merge the current mapping into the basic block starting at bci
1524 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
1525 void Parse::merge_exception(int target_bci) {
1526 assert(sp() == 1, "must have only the throw exception on the stack");
1527 Block* target = successor_for_bci(target_bci);
1528 if (target == NULL) { handle_missing_successor(target_bci); return; }
1529 assert(target->is_handler(), "exceptions are handled by special blocks");
1530 int pnum = target->add_new_path();
1531 merge_common(target, pnum);
1532 }
1533
1534 //--------------------handle_missing_successor---------------------------------
1535 void Parse::handle_missing_successor(int target_bci) {
1536 #ifndef PRODUCT
1537 Block* b = block();
1538 int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1539 tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1540 #endif
1541 ShouldNotReachHere();
1542 }
1543
1544 //--------------------------merge_common---------------------------------------
1545 void Parse::merge_common(Parse::Block* target, int pnum) {
1546 if (TraceOptoParse) {
1547 tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1548 }
1549
1550 // Zap extra stack slots to top
1551 assert(sp() == target->start_sp(), "");
1552 clean_stack(sp());
1553
1554 if (!target->is_merged()) { // No prior mapping at this bci
1555 if (TraceOptoParse) { tty->print(" with empty state"); }
1556
1557 // If this path is dead, do not bother capturing it as a merge.
1558 // It is "as if" we had 1 fewer predecessors from the beginning.
1559 if (stopped()) {
1560 if (TraceOptoParse) tty->print_cr(", but path is dead and doesn't count");
1561 return;
1562 }
1563
1564 // Record that a new block has been merged.
1565 ++_blocks_merged;
1566
1567 // Make a region if we know there are multiple or unpredictable inputs.
1568 // (Also, if this is a plain fall-through, we might see another region,
1569 // which must not be allowed into this block's map.)
1570 if (pnum > PhiNode::Input // Known multiple inputs.
1571 || target->is_handler() // These have unpredictable inputs.
1572 || target->is_loop_head() // Known multiple inputs
1573 || control()->is_Region()) { // We must hide this guy.
1574
1575 int current_bci = bci();
1576 set_parse_bci(target->start()); // Set target bci
1577 if (target->is_SEL_head()) {
1578 DEBUG_ONLY( target->mark_merged_backedge(block()); )
1579 if (target->start() == 0) {
1580 // Add loop predicate for the special case when
1581 // there are backbranches to the method entry.
1582 add_predicate();
1583 }
1584 }
1585 // Add a Region to start the new basic block. Phis will be added
1586 // later lazily.
1587 int edges = target->pred_count();
1588 if (edges < pnum) edges = pnum; // might be a new path!
1589 RegionNode *r = new (C) RegionNode(edges+1);
1590 gvn().set_type(r, Type::CONTROL);
1591 record_for_igvn(r);
1592 // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1593 // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1594 r->init_req(pnum, control());
1595 set_control(r);
1596 set_parse_bci(current_bci); // Restore bci
1597 }
1598
1599 // Convert the existing Parser mapping into a mapping at this bci.
1600 store_state_to(target);
1601 assert(target->is_merged(), "do not come here twice");
1602
1603 } else { // Prior mapping at this bci
1604 if (TraceOptoParse) { tty->print(" with previous state"); }
1605 #ifdef ASSERT
1606 if (target->is_SEL_head()) {
1607 target->mark_merged_backedge(block());
1608 }
1609 #endif
1610 // We must not manufacture more phis if the target is already parsed.
1611 bool nophi = target->is_parsed();
1612
1613 SafePointNode* newin = map();// Hang on to incoming mapping
1614 Block* save_block = block(); // Hang on to incoming block;
1615 load_state_from(target); // Get prior mapping
1616
1617 assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1618 assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1619 assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1620 assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1621
1622 // Iterate over my current mapping and the old mapping.
1623 // Where different, insert Phi functions.
1624 // Use any existing Phi functions.
1625 assert(control()->is_Region(), "must be merging to a region");
1626 RegionNode* r = control()->as_Region();
1627
1628 // Compute where to merge into
1629 // Merge incoming control path
1630 r->init_req(pnum, newin->control());
1631
1632 if (pnum == 1) { // Last merge for this Region?
1633 if (!block()->flow()->is_irreducible_entry()) {
1634 Node* result = _gvn.transform_no_reclaim(r);
1635 if (r != result && TraceOptoParse) {
1636 tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1637 }
1638 }
1639 record_for_igvn(r);
1640 }
1641
1642 // Update all the non-control inputs to map:
1643 assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1644 bool check_elide_phi = target->is_SEL_backedge(save_block);
1645 for (uint j = 1; j < newin->req(); j++) {
1646 Node* m = map()->in(j); // Current state of target.
1647 Node* n = newin->in(j); // Incoming change to target state.
1648 PhiNode* phi;
1649 if (m->is_Phi() && m->as_Phi()->region() == r)
1650 phi = m->as_Phi();
1651 else
1652 phi = NULL;
1653 if (m != n) { // Different; must merge
1654 switch (j) {
1655 // Frame pointer and Return Address never changes
1656 case TypeFunc::FramePtr:// Drop m, use the original value
1657 case TypeFunc::ReturnAdr:
1658 break;
1659 case TypeFunc::Memory: // Merge inputs to the MergeMem node
1660 assert(phi == NULL, "the merge contains phis, not vice versa");
1661 merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1662 continue;
1663 default: // All normal stuff
1664 if (phi == NULL) {
1665 const JVMState* jvms = map()->jvms();
1666 if (EliminateNestedLocks &&
1667 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1668 // BoxLock nodes are not commoning.
1669 // Use old BoxLock node as merged box.
1670 assert(newin->jvms()->is_monitor_box(j), "sanity");
1671 // This assert also tests that nodes are BoxLock.
1672 assert(BoxLockNode::same_slot(n, m), "sanity");
1673 C->gvn_replace_by(n, m);
1674 } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1675 phi = ensure_phi(j, nophi);
1676 }
1677 }
1678 break;
1679 }
1680 }
1681 // At this point, n might be top if:
1682 // - there is no phi (because TypeFlow detected a conflict), or
1683 // - the corresponding control edges is top (a dead incoming path)
1684 // It is a bug if we create a phi which sees a garbage value on a live path.
1685
1686 if (phi != NULL) {
1687 assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1688 assert(phi->region() == r, "");
1689 phi->set_req(pnum, n); // Then add 'n' to the merge
1690 if (pnum == PhiNode::Input) {
1691 // Last merge for this Phi.
1692 // So far, Phis have had a reasonable type from ciTypeFlow.
1693 // Now _gvn will join that with the meet of current inputs.
1694 // BOTTOM is never permissible here, 'cause pessimistically
1695 // Phis of pointers cannot lose the basic pointer type.
1696 debug_only(const Type* bt1 = phi->bottom_type());
1697 assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1698 map()->set_req(j, _gvn.transform_no_reclaim(phi));
1699 debug_only(const Type* bt2 = phi->bottom_type());
1700 assert(bt2->higher_equal(bt1), "must be consistent with type-flow");
1701 record_for_igvn(phi);
1702 }
1703 }
1704 } // End of for all values to be merged
1705
1706 if (pnum == PhiNode::Input &&
1707 !r->in(0)) { // The occasional useless Region
1708 assert(control() == r, "");
1709 set_control(r->nonnull_req());
1710 }
1711
1712 map()->merge_replaced_nodes_with(newin);
1713
1714 // newin has been subsumed into the lazy merge, and is now dead.
1715 set_block(save_block);
1716
1717 stop(); // done with this guy, for now
1718 }
1719
1720 if (TraceOptoParse) {
1721 tty->print_cr(" on path %d", pnum);
1722 }
1723
1724 // Done with this parser state.
1725 assert(stopped(), "");
1726 }
1727
1728
1729 //--------------------------merge_memory_edges---------------------------------
1730 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1731 // (nophi means we must not create phis, because we already parsed here)
1732 assert(n != NULL, "");
1733 // Merge the inputs to the MergeMems
1734 MergeMemNode* m = merged_memory();
1735
1736 assert(control()->is_Region(), "must be merging to a region");
1737 RegionNode* r = control()->as_Region();
1738
1739 PhiNode* base = NULL;
1740 MergeMemNode* remerge = NULL;
1741 for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1742 Node *p = mms.force_memory();
1743 Node *q = mms.memory2();
1744 if (mms.is_empty() && nophi) {
1745 // Trouble: No new splits allowed after a loop body is parsed.
1746 // Instead, wire the new split into a MergeMem on the backedge.
1747 // The optimizer will sort it out, slicing the phi.
1748 if (remerge == NULL) {
1749 assert(base != NULL, "");
1750 assert(base->in(0) != NULL, "should not be xformed away");
1751 remerge = MergeMemNode::make(C, base->in(pnum));
1752 gvn().set_type(remerge, Type::MEMORY);
1753 base->set_req(pnum, remerge);
1754 }
1755 remerge->set_memory_at(mms.alias_idx(), q);
1756 continue;
1757 }
1758 assert(!q->is_MergeMem(), "");
1759 PhiNode* phi;
1760 if (p != q) {
1761 phi = ensure_memory_phi(mms.alias_idx(), nophi);
1762 } else {
1763 if (p->is_Phi() && p->as_Phi()->region() == r)
1764 phi = p->as_Phi();
1765 else
1766 phi = NULL;
1767 }
1768 // Insert q into local phi
1769 if (phi != NULL) {
1770 assert(phi->region() == r, "");
1771 p = phi;
1772 phi->set_req(pnum, q);
1773 if (mms.at_base_memory()) {
1774 base = phi; // delay transforming it
1775 } else if (pnum == 1) {
1776 record_for_igvn(phi);
1777 p = _gvn.transform_no_reclaim(phi);
1778 }
1779 mms.set_memory(p);// store back through the iterator
1780 }
1781 }
1782 // Transform base last, in case we must fiddle with remerging.
1783 if (base != NULL && pnum == 1) {
1784 record_for_igvn(base);
1785 m->set_base_memory( _gvn.transform_no_reclaim(base) );
1786 }
1787 }
1788
1789
1790 //------------------------ensure_phis_everywhere-------------------------------
1791 void Parse::ensure_phis_everywhere() {
1792 ensure_phi(TypeFunc::I_O);
1793
1794 // Ensure a phi on all currently known memories.
1795 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
1796 ensure_memory_phi(mms.alias_idx());
1797 debug_only(mms.set_memory()); // keep the iterator happy
1798 }
1799
1800 // Note: This is our only chance to create phis for memory slices.
1801 // If we miss a slice that crops up later, it will have to be
1802 // merged into the base-memory phi that we are building here.
1803 // Later, the optimizer will comb out the knot, and build separate
1804 // phi-loops for each memory slice that matters.
1805
1806 // Monitors must nest nicely and not get confused amongst themselves.
1807 // Phi-ify everything up to the monitors, though.
1808 uint monoff = map()->jvms()->monoff();
1809 uint nof_monitors = map()->jvms()->nof_monitors();
1810
1811 assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
1812 bool check_elide_phi = block()->is_SEL_head();
1813 for (uint i = TypeFunc::Parms; i < monoff; i++) {
1814 if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
1815 ensure_phi(i);
1816 }
1817 }
1818
1819 // Even monitors need Phis, though they are well-structured.
1820 // This is true for OSR methods, and also for the rare cases where
1821 // a monitor object is the subject of a replace_in_map operation.
1822 // See bugs 4426707 and 5043395.
1823 for (uint m = 0; m < nof_monitors; m++) {
1824 ensure_phi(map()->jvms()->monitor_obj_offset(m));
1825 }
1826 }
1827
1828
1829 //-----------------------------add_new_path------------------------------------
1830 // Add a previously unaccounted predecessor to this block.
1831 int Parse::Block::add_new_path() {
1832 // If there is no map, return the lowest unused path number.
1833 if (!is_merged()) return pred_count()+1; // there will be a map shortly
1834
1835 SafePointNode* map = start_map();
1836 if (!map->control()->is_Region())
1837 return pred_count()+1; // there may be a region some day
1838 RegionNode* r = map->control()->as_Region();
1839
1840 // Add new path to the region.
1841 uint pnum = r->req();
1842 r->add_req(NULL);
1843
1844 for (uint i = 1; i < map->req(); i++) {
1845 Node* n = map->in(i);
1846 if (i == TypeFunc::Memory) {
1847 // Ensure a phi on all currently known memories.
1848 for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1849 Node* phi = mms.memory();
1850 if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1851 assert(phi->req() == pnum, "must be same size as region");
1852 phi->add_req(NULL);
1853 }
1854 }
1855 } else {
1856 if (n->is_Phi() && n->as_Phi()->region() == r) {
1857 assert(n->req() == pnum, "must be same size as region");
1858 n->add_req(NULL);
1859 }
1860 }
1861 }
1862
1863 return pnum;
1864 }
1865
1866 //------------------------------ensure_phi-------------------------------------
1867 // Turn the idx'th entry of the current map into a Phi
1868 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
1869 SafePointNode* map = this->map();
1870 Node* region = map->control();
1871 assert(region->is_Region(), "");
1872
1873 Node* o = map->in(idx);
1874 assert(o != NULL, "");
1875
1876 if (o == top()) return NULL; // TOP always merges into TOP
1877
1878 if (o->is_Phi() && o->as_Phi()->region() == region) {
1879 return o->as_Phi();
1880 }
1881
1882 // Now use a Phi here for merging
1883 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1884 const JVMState* jvms = map->jvms();
1885 const Type* t;
1886 if (jvms->is_loc(idx)) {
1887 t = block()->local_type_at(idx - jvms->locoff());
1888 } else if (jvms->is_stk(idx)) {
1889 t = block()->stack_type_at(idx - jvms->stkoff());
1890 } else if (jvms->is_mon(idx)) {
1891 assert(!jvms->is_monitor_box(idx), "no phis for boxes");
1892 t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
1893 } else if ((uint)idx < TypeFunc::Parms) {
1894 t = o->bottom_type(); // Type::RETURN_ADDRESS or such-like.
1895 } else {
1896 assert(false, "no type information for this phi");
1897 }
1898
1899 // If the type falls to bottom, then this must be a local that
1900 // is mixing ints and oops or some such. Forcing it to top
1901 // makes it go dead.
1902 if (t == Type::BOTTOM) {
1903 map->set_req(idx, top());
1904 return NULL;
1905 }
1906
1907 // Do not create phis for top either.
1908 // A top on a non-null control flow must be an unused even after the.phi.
1909 if (t == Type::TOP || t == Type::HALF) {
1910 map->set_req(idx, top());
1911 return NULL;
1912 }
1913
1914 PhiNode* phi = PhiNode::make(region, o, t);
1915 gvn().set_type(phi, t);
1916 if (C->do_escape_analysis()) record_for_igvn(phi);
1917 map->set_req(idx, phi);
1918 return phi;
1919 }
1920
1921 //--------------------------ensure_memory_phi----------------------------------
1922 // Turn the idx'th slice of the current memory into a Phi
1923 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
1924 MergeMemNode* mem = merged_memory();
1925 Node* region = control();
1926 assert(region->is_Region(), "");
1927
1928 Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
1929 assert(o != NULL && o != top(), "");
1930
1931 PhiNode* phi;
1932 if (o->is_Phi() && o->as_Phi()->region() == region) {
1933 phi = o->as_Phi();
1934 if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
1935 // clone the shared base memory phi to make a new memory split
1936 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1937 const Type* t = phi->bottom_type();
1938 const TypePtr* adr_type = C->get_adr_type(idx);
1939 phi = phi->slice_memory(adr_type);
1940 gvn().set_type(phi, t);
1941 }
1942 return phi;
1943 }
1944
1945 // Now use a Phi here for merging
1946 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1947 const Type* t = o->bottom_type();
1948 const TypePtr* adr_type = C->get_adr_type(idx);
1949 phi = PhiNode::make(region, o, t, adr_type);
1950 gvn().set_type(phi, t);
1951 if (idx == Compile::AliasIdxBot)
1952 mem->set_base_memory(phi);
1953 else
1954 mem->set_memory_at(idx, phi);
1955 return phi;
1956 }
1957
1958 //------------------------------call_register_finalizer-----------------------
1959 // Check the klass of the receiver and call register_finalizer if the
1960 // class need finalization.
1961 void Parse::call_register_finalizer() {
1962 Node* receiver = local(0);
1963 assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
1964 "must have non-null instance type");
1965
1966 const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
1967 if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
1968 // The type isn't known exactly so see if CHA tells us anything.
1969 ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
1970 if (!Dependencies::has_finalizable_subclass(ik)) {
1971 // No finalizable subclasses so skip the dynamic check.
1972 C->dependencies()->assert_has_no_finalizable_subclasses(ik);
1973 return;
1974 }
1975 }
1976
1977 // Insert a dynamic test for whether the instance needs
1978 // finalization. In general this will fold up since the concrete
1979 // class is often visible so the access flags are constant.
1980 Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
1981 Node* klass = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), klass_addr, TypeInstPtr::KLASS) );
1982
1983 Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
1984 Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT);
1985
1986 Node* mask = _gvn.transform(new (C) AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
1987 Node* check = _gvn.transform(new (C) CmpINode(mask, intcon(0)));
1988 Node* test = _gvn.transform(new (C) BoolNode(check, BoolTest::ne));
1989
1990 IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
1991
1992 RegionNode* result_rgn = new (C) RegionNode(3);
1993 record_for_igvn(result_rgn);
1994
1995 Node *skip_register = _gvn.transform(new (C) IfFalseNode(iff));
1996 result_rgn->init_req(1, skip_register);
1997
1998 Node *needs_register = _gvn.transform(new (C) IfTrueNode(iff));
1999 set_control(needs_register);
2000 if (stopped()) {
2001 // There is no slow path.
2002 result_rgn->init_req(2, top());
2003 } else {
2004 Node *call = make_runtime_call(RC_NO_LEAF,
2005 OptoRuntime::register_finalizer_Type(),
2006 OptoRuntime::register_finalizer_Java(),
2007 NULL, TypePtr::BOTTOM,
2008 receiver);
2009 make_slow_call_ex(call, env()->Throwable_klass(), true);
2010
2011 Node* fast_io = call->in(TypeFunc::I_O);
2012 Node* fast_mem = call->in(TypeFunc::Memory);
2013 // These two phis are pre-filled with copies of of the fast IO and Memory
2014 Node* io_phi = PhiNode::make(result_rgn, fast_io, Type::ABIO);
2015 Node* mem_phi = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
2016
2017 result_rgn->init_req(2, control());
2018 io_phi ->init_req(2, i_o());
2019 mem_phi ->init_req(2, reset_memory());
2020
2021 set_all_memory( _gvn.transform(mem_phi) );
2022 set_i_o( _gvn.transform(io_phi) );
2023 }
2024
2025 set_control( _gvn.transform(result_rgn) );
2026 }
2027
2028 //------------------------------return_current---------------------------------
2029 // Append current _map to _exit_return
2030 void Parse::return_current(Node* value) {
2031 if (RegisterFinalizersAtInit &&
2032 method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2033 call_register_finalizer();
2034 }
2035
2036 // Do not set_parse_bci, so that return goo is credited to the return insn.
2037 set_bci(InvocationEntryBci);
2038 if (method()->is_synchronized() && GenerateSynchronizationCode) {
2039 shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2040 }
2041 if (C->env()->dtrace_method_probes()) {
2042 make_dtrace_method_exit(method());
2043 }
2044 SafePointNode* exit_return = _exits.map();
2045 exit_return->in( TypeFunc::Control )->add_req( control() );
2046 exit_return->in( TypeFunc::I_O )->add_req( i_o () );
2047 Node *mem = exit_return->in( TypeFunc::Memory );
2048 for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2049 if (mms.is_empty()) {
2050 // get a copy of the base memory, and patch just this one input
2051 const TypePtr* adr_type = mms.adr_type(C);
2052 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2053 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2054 gvn().set_type_bottom(phi);
2055 phi->del_req(phi->req()-1); // prepare to re-patch
2056 mms.set_memory(phi);
2057 }
2058 mms.memory()->add_req(mms.memory2());
2059 }
2060
2061 // frame pointer is always same, already captured
2062 if (value != NULL) {
2063 // If returning oops to an interface-return, there is a silent free
2064 // cast from oop to interface allowed by the Verifier. Make it explicit
2065 // here.
2066 Node* phi = _exits.argument(0);
2067 const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
2068 if( tr && tr->klass()->is_loaded() &&
2069 tr->klass()->is_interface() ) {
2070 const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
2071 if (tp && tp->klass()->is_loaded() &&
2072 !tp->klass()->is_interface()) {
2073 // sharpen the type eagerly; this eases certain assert checking
2074 if (tp->higher_equal(TypeInstPtr::NOTNULL))
2075 tr = tr->join(TypeInstPtr::NOTNULL)->is_instptr();
2076 value = _gvn.transform(new (C) CheckCastPPNode(0,value,tr));
2077 }
2078 }
2079 phi->add_req(value);
2080 }
2081
2082 if (_first_return) {
2083 _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
2084 _first_return = false;
2085 } else {
2086 _exits.map()->merge_replaced_nodes_with(map());
2087 }
2088
2089 stop_and_kill_map(); // This CFG path dies here
2090 }
2091
2092
2093 //------------------------------add_safepoint----------------------------------
2094 void Parse::add_safepoint() {
2095 // See if we can avoid this safepoint. No need for a SafePoint immediately
2096 // after a Call (except Leaf Call) or another SafePoint.
2097 Node *proj = control();
2098 bool add_poll_param = SafePointNode::needs_polling_address_input();
2099 uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2100 if( proj->is_Proj() ) {
2101 Node *n0 = proj->in(0);
2102 if( n0->is_Catch() ) {
2103 n0 = n0->in(0)->in(0);
2104 assert( n0->is_Call(), "expect a call here" );
2105 }
2106 if( n0->is_Call() ) {
2107 if( n0->as_Call()->guaranteed_safepoint() )
2108 return;
2109 } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2110 return;
2111 }
2112 }
2113
2114 // Clear out dead values from the debug info.
2115 kill_dead_locals();
2116
2117 // Clone the JVM State
2118 SafePointNode *sfpnt = new (C) SafePointNode(parms, NULL);
2119
2120 // Capture memory state BEFORE a SafePoint. Since we can block at a
2121 // SafePoint we need our GC state to be safe; i.e. we need all our current
2122 // write barriers (card marks) to not float down after the SafePoint so we
2123 // must read raw memory. Likewise we need all oop stores to match the card
2124 // marks. If deopt can happen, we need ALL stores (we need the correct JVM
2125 // state on a deopt).
2126
2127 // We do not need to WRITE the memory state after a SafePoint. The control
2128 // edge will keep card-marks and oop-stores from floating up from below a
2129 // SafePoint and our true dependency added here will keep them from floating
2130 // down below a SafePoint.
2131
2132 // Clone the current memory state
2133 Node* mem = MergeMemNode::make(C, map()->memory());
2134
2135 mem = _gvn.transform(mem);
2136
2137 // Pass control through the safepoint
2138 sfpnt->init_req(TypeFunc::Control , control());
2139 // Fix edges normally used by a call
2140 sfpnt->init_req(TypeFunc::I_O , top() );
2141 sfpnt->init_req(TypeFunc::Memory , mem );
2142 sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2143 sfpnt->init_req(TypeFunc::FramePtr , top() );
2144
2145 // Create a node for the polling address
2146 if( add_poll_param ) {
2147 Node *polladr = ConPNode::make(C, (address)os::get_polling_page());
2148 sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2149 }
2150
2151 // Fix up the JVM State edges
2152 add_safepoint_edges(sfpnt);
2153 Node *transformed_sfpnt = _gvn.transform(sfpnt);
2154 set_control(transformed_sfpnt);
2155
2156 // Provide an edge from root to safepoint. This makes the safepoint
2157 // appear useful until the parse has completed.
2158 if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2159 assert(C->root() != NULL, "Expect parse is still valid");
2160 C->root()->add_prec(transformed_sfpnt);
2161 }
2162 }
2163
2164 #ifndef PRODUCT
2165 //------------------------show_parse_info--------------------------------------
2166 void Parse::show_parse_info() {
2167 InlineTree* ilt = NULL;
2168 if (C->ilt() != NULL) {
2169 JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2170 ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2171 }
2172 if (PrintCompilation && Verbose) {
2173 if (depth() == 1) {
2174 if( ilt->count_inlines() ) {
2175 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2176 ilt->count_inline_bcs());
2177 tty->cr();
2178 }
2179 } else {
2180 if (method()->is_synchronized()) tty->print("s");
2181 if (method()->has_exception_handlers()) tty->print("!");
2182 // Check this is not the final compiled version
2183 if (C->trap_can_recompile()) {
2184 tty->print("-");
2185 } else {
2186 tty->print(" ");
2187 }
2188 method()->print_short_name();
2189 if (is_osr_parse()) {
2190 tty->print(" @ %d", osr_bci());
2191 }
2192 tty->print(" (%d bytes)",method()->code_size());
2193 if (ilt->count_inlines()) {
2194 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2195 ilt->count_inline_bcs());
2196 }
2197 tty->cr();
2198 }
2199 }
2200 if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2201 // Print that we succeeded; suppress this message on the first osr parse.
2202
2203 if (method()->is_synchronized()) tty->print("s");
2204 if (method()->has_exception_handlers()) tty->print("!");
2205 // Check this is not the final compiled version
2206 if (C->trap_can_recompile() && depth() == 1) {
2207 tty->print("-");
2208 } else {
2209 tty->print(" ");
2210 }
2211 if( depth() != 1 ) { tty->print(" "); } // missing compile count
2212 for (int i = 1; i < depth(); ++i) { tty->print(" "); }
2213 method()->print_short_name();
2214 if (is_osr_parse()) {
2215 tty->print(" @ %d", osr_bci());
2216 }
2217 if (ilt->caller_bci() != -1) {
2218 tty->print(" @ %d", ilt->caller_bci());
2219 }
2220 tty->print(" (%d bytes)",method()->code_size());
2221 if (ilt->count_inlines()) {
2222 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2223 ilt->count_inline_bcs());
2224 }
2225 tty->cr();
2226 }
2227 }
2228
2229
2230 //------------------------------dump-------------------------------------------
2231 // Dump information associated with the bytecodes of current _method
2232 void Parse::dump() {
2233 if( method() != NULL ) {
2234 // Iterate over bytecodes
2235 ciBytecodeStream iter(method());
2236 for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2237 dump_bci( iter.cur_bci() );
2238 tty->cr();
2239 }
2240 }
2241 }
2242
2243 // Dump information associated with a byte code index, 'bci'
2244 void Parse::dump_bci(int bci) {
2245 // Output info on merge-points, cloning, and within _jsr..._ret
2246 // NYI
2247 tty->print(" bci:%d", bci);
2248 }
2249
2250 #endif