1 /*
2 * Copyright (c) 1997, 2013, 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/method.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, Parse* parent)
385 : _exits(caller), _parent(parent)
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 _alloc_with_final = NULL;
394 _entry_bci = InvocationEntryBci;
395 _tf = NULL;
396 _block = NULL;
397 debug_only(_block_count = -1);
398 debug_only(_blocks = (Block*)-1);
399 #ifndef PRODUCT
400 if (PrintCompilation || PrintOpto) {
401 // Make sure I have an inline tree, so I can print messages about it.
402 JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
403 InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method);
404 }
405 _max_switch_depth = 0;
406 _est_switch_depth = 0;
407 #endif
408
409 _tf = TypeFunc::make(method());
410 _iter.reset_to_method(method());
411 _flow = method()->get_flow_analysis();
412 if (_flow->failing()) {
413 C->record_method_not_compilable_all_tiers(_flow->failure_reason());
414 }
415
416 #ifndef PRODUCT
417 if (_flow->has_irreducible_entry()) {
418 C->set_parsed_irreducible_loop(true);
419 }
420 #endif
421
422 if (_expected_uses <= 0) {
423 _prof_factor = 1;
424 } else {
425 float prof_total = parse_method->interpreter_invocation_count();
426 if (prof_total <= _expected_uses) {
427 _prof_factor = 1;
428 } else {
429 _prof_factor = _expected_uses / prof_total;
430 }
431 }
432
433 CompileLog* log = C->log();
434 if (log != NULL) {
435 log->begin_head("parse method='%d' uses='%g'",
436 log->identify(parse_method), expected_uses);
437 if (depth() == 1 && C->is_osr_compilation()) {
438 log->print(" osr_bci='%d'", C->entry_bci());
439 }
440 log->stamp();
441 log->end_head();
442 }
443
444 // Accumulate deoptimization counts.
445 // (The range_check and store_check counts are checked elsewhere.)
446 ciMethodData* md = method()->method_data();
447 for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
448 uint md_count = md->trap_count(reason);
449 if (md_count != 0) {
450 if (md_count == md->trap_count_limit())
451 md_count += md->overflow_trap_count();
452 uint total_count = C->trap_count(reason);
453 uint old_count = total_count;
454 total_count += md_count;
455 // Saturate the add if it overflows.
456 if (total_count < old_count || total_count < md_count)
457 total_count = (uint)-1;
458 C->set_trap_count(reason, total_count);
459 if (log != NULL)
460 log->elem("observe trap='%s' count='%d' total='%d'",
461 Deoptimization::trap_reason_name(reason),
462 md_count, total_count);
463 }
464 }
465 // Accumulate total sum of decompilations, also.
466 C->set_decompile_count(C->decompile_count() + md->decompile_count());
467
468 _count_invocations = C->do_count_invocations();
469 _method_data_update = C->do_method_data_update();
470
471 if (log != NULL && method()->has_exception_handlers()) {
472 log->elem("observe that='has_exception_handlers'");
473 }
474
475 assert(method()->can_be_compiled(), "Can not parse this method, cutout earlier");
476 assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
477
478 // Always register dependence if JVMTI is enabled, because
479 // either breakpoint setting or hotswapping of methods may
480 // cause deoptimization.
481 if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
482 C->dependencies()->assert_evol_method(method());
483 }
484
485 methods_seen++;
486
487 // Do some special top-level things.
488 if (depth() == 1 && C->is_osr_compilation()) {
489 _entry_bci = C->entry_bci();
490 _flow = method()->get_osr_flow_analysis(osr_bci());
491 if (_flow->failing()) {
492 C->record_method_not_compilable(_flow->failure_reason());
493 #ifndef PRODUCT
494 if (PrintOpto && (Verbose || WizardMode)) {
495 tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
496 if (Verbose) {
497 method()->print();
498 method()->print_codes();
499 _flow->print();
500 }
501 }
502 #endif
503 }
504 _tf = C->tf(); // the OSR entry type is different
505 }
506
507 #ifdef ASSERT
508 if (depth() == 1) {
509 assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
510 if (C->tf() != tf()) {
511 MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
512 assert(C->env()->system_dictionary_modification_counter_changed(),
513 "Must invalidate if TypeFuncs differ");
514 }
515 } else {
516 assert(!this->is_osr_parse(), "no recursive OSR");
517 }
518 #endif
519
520 methods_parsed++;
521 #ifndef PRODUCT
522 // add method size here to guarantee that inlined methods are added too
523 if (TimeCompiler)
524 _total_bytes_compiled += method()->code_size();
525
526 show_parse_info();
527 #endif
528
529 if (failing()) {
530 if (log) log->done("parse");
531 return;
532 }
533
534 gvn().set_type(root(), root()->bottom_type());
535 gvn().transform(top());
536
537 // Import the results of the ciTypeFlow.
538 init_blocks();
539
540 // Merge point for all normal exits
541 build_exits();
542
543 // Setup the initial JVM state map.
544 SafePointNode* entry_map = create_entry_map();
545
546 // Check for bailouts during map initialization
547 if (failing() || entry_map == NULL) {
548 if (log) log->done("parse");
549 return;
550 }
551
552 Node_Notes* caller_nn = C->default_node_notes();
553 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
554 if (DebugInlinedCalls || depth() == 1) {
555 C->set_default_node_notes(make_node_notes(caller_nn));
556 }
557
558 if (is_osr_parse()) {
559 Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
560 entry_map->set_req(TypeFunc::Parms+0, top());
561 set_map(entry_map);
562 load_interpreter_state(osr_buf);
563 } else {
564 set_map(entry_map);
565 do_method_entry();
566 }
567 if (depth() == 1) {
568 // Add check to deoptimize the nmethod if RTM state was changed
569 rtm_deopt();
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 //-------------------------------build_exits----------------------------------
716 // Build normal and exceptional exit merge points.
717 void Parse::build_exits() {
718 // make a clone of caller to prevent sharing of side-effects
719 _exits.set_map(_exits.clone_map());
720 _exits.clean_stack(_exits.sp());
721 _exits.sync_jvms();
722
723 RegionNode* region = new (C) RegionNode(1);
724 record_for_igvn(region);
725 gvn().set_type_bottom(region);
726 _exits.set_control(region);
727
728 // Note: iophi and memphi are not transformed until do_exits.
729 Node* iophi = new (C) PhiNode(region, Type::ABIO);
730 Node* memphi = new (C) PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
731 gvn().set_type_bottom(iophi);
732 gvn().set_type_bottom(memphi);
733 _exits.set_i_o(iophi);
734 _exits.set_all_memory(memphi);
735
736 // Add a return value to the exit state. (Do not push it yet.)
737 if (tf()->range()->cnt() > TypeFunc::Parms) {
738 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
739 // Don't "bind" an unloaded return klass to the ret_phi. If the klass
740 // becomes loaded during the subsequent parsing, the loaded and unloaded
741 // types will not join when we transform and push in do_exits().
742 const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
743 if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
744 ret_type = TypeOopPtr::BOTTOM;
745 }
746 int ret_size = type2size[ret_type->basic_type()];
747 Node* ret_phi = new (C) PhiNode(region, ret_type);
748 gvn().set_type_bottom(ret_phi);
749 _exits.ensure_stack(ret_size);
750 assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
751 assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
752 _exits.set_argument(0, ret_phi); // here is where the parser finds it
753 // Note: ret_phi is not yet pushed, until do_exits.
754 }
755 }
756
757
758 //----------------------------build_start_state-------------------------------
759 // Construct a state which contains only the incoming arguments from an
760 // unknown caller. The method & bci will be NULL & InvocationEntryBci.
761 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
762 int arg_size = tf->domain()->cnt();
763 int max_size = MAX2(arg_size, (int)tf->range()->cnt());
764 JVMState* jvms = new (this) JVMState(max_size - TypeFunc::Parms);
765 SafePointNode* map = new (this) SafePointNode(max_size, NULL);
766 record_for_igvn(map);
767 assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
768 Node_Notes* old_nn = default_node_notes();
769 if (old_nn != NULL && has_method()) {
770 Node_Notes* entry_nn = old_nn->clone(this);
771 JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
772 entry_jvms->set_offsets(0);
773 entry_jvms->set_bci(entry_bci());
774 entry_nn->set_jvms(entry_jvms);
775 set_default_node_notes(entry_nn);
776 }
777 uint i;
778 for (i = 0; i < (uint)arg_size; i++) {
779 Node* parm = initial_gvn()->transform(new (this) ParmNode(start, i));
780 map->init_req(i, parm);
781 // Record all these guys for later GVN.
782 record_for_igvn(parm);
783 }
784 for (; i < map->req(); i++) {
785 map->init_req(i, top());
786 }
787 assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
788 set_default_node_notes(old_nn);
789 map->set_jvms(jvms);
790 jvms->set_map(map);
791 return jvms;
792 }
793
794 //-----------------------------make_node_notes---------------------------------
795 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
796 if (caller_nn == NULL) return NULL;
797 Node_Notes* nn = caller_nn->clone(C);
798 JVMState* caller_jvms = nn->jvms();
799 JVMState* jvms = new (C) JVMState(method(), caller_jvms);
800 jvms->set_offsets(0);
801 jvms->set_bci(_entry_bci);
802 nn->set_jvms(jvms);
803 return nn;
804 }
805
806
807 //--------------------------return_values--------------------------------------
808 void Compile::return_values(JVMState* jvms) {
809 GraphKit kit(jvms);
810 Node* ret = new (this) ReturnNode(TypeFunc::Parms,
811 kit.control(),
812 kit.i_o(),
813 kit.reset_memory(),
814 kit.frameptr(),
815 kit.returnadr());
816 // Add zero or 1 return values
817 int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
818 if (ret_size > 0) {
819 kit.inc_sp(-ret_size); // pop the return value(s)
820 kit.sync_jvms();
821 ret->add_req(kit.argument(0));
822 // Note: The second dummy edge is not needed by a ReturnNode.
823 }
824 // bind it to root
825 root()->add_req(ret);
826 record_for_igvn(ret);
827 initial_gvn()->transform_no_reclaim(ret);
828 }
829
830 //------------------------rethrow_exceptions-----------------------------------
831 // Bind all exception states in the list into a single RethrowNode.
832 void Compile::rethrow_exceptions(JVMState* jvms) {
833 GraphKit kit(jvms);
834 if (!kit.has_exceptions()) return; // nothing to generate
835 // Load my combined exception state into the kit, with all phis transformed:
836 SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
837 Node* ex_oop = kit.use_exception_state(ex_map);
838 RethrowNode* exit = new (this) RethrowNode(kit.control(),
839 kit.i_o(), kit.reset_memory(),
840 kit.frameptr(), kit.returnadr(),
841 // like a return but with exception input
842 ex_oop);
843 // bind to root
844 root()->add_req(exit);
845 record_for_igvn(exit);
846 initial_gvn()->transform_no_reclaim(exit);
847 }
848
849 //---------------------------do_exceptions-------------------------------------
850 // Process exceptions arising from the current bytecode.
851 // Send caught exceptions to the proper handler within this method.
852 // Unhandled exceptions feed into _exit.
853 void Parse::do_exceptions() {
854 if (!has_exceptions()) return;
855
856 if (failing()) {
857 // Pop them all off and throw them away.
858 while (pop_exception_state() != NULL) ;
859 return;
860 }
861
862 PreserveJVMState pjvms(this, false);
863
864 SafePointNode* ex_map;
865 while ((ex_map = pop_exception_state()) != NULL) {
866 if (!method()->has_exception_handlers()) {
867 // Common case: Transfer control outward.
868 // Doing it this early allows the exceptions to common up
869 // even between adjacent method calls.
870 throw_to_exit(ex_map);
871 } else {
872 // Have to look at the exception first.
873 assert(stopped(), "catch_inline_exceptions trashes the map");
874 catch_inline_exceptions(ex_map);
875 stop_and_kill_map(); // we used up this exception state; kill it
876 }
877 }
878
879 // We now return to our regularly scheduled program:
880 }
881
882 //---------------------------throw_to_exit-------------------------------------
883 // Merge the given map into an exception exit from this method.
884 // The exception exit will handle any unlocking of receiver.
885 // The ex_oop must be saved within the ex_map, unlike merge_exception.
886 void Parse::throw_to_exit(SafePointNode* ex_map) {
887 // Pop the JVMS to (a copy of) the caller.
888 GraphKit caller;
889 caller.set_map_clone(_caller->map());
890 caller.set_bci(_caller->bci());
891 caller.set_sp(_caller->sp());
892 // Copy out the standard machine state:
893 for (uint i = 0; i < TypeFunc::Parms; i++) {
894 caller.map()->set_req(i, ex_map->in(i));
895 }
896 // ...and the exception:
897 Node* ex_oop = saved_ex_oop(ex_map);
898 SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
899 // Finally, collect the new exception state in my exits:
900 _exits.add_exception_state(caller_ex_map);
901 }
902
903 //------------------------------do_exits---------------------------------------
904 void Parse::do_exits() {
905 set_parse_bci(InvocationEntryBci);
906
907 // Now peephole on the return bits
908 Node* region = _exits.control();
909 _exits.set_control(gvn().transform(region));
910
911 Node* iophi = _exits.i_o();
912 _exits.set_i_o(gvn().transform(iophi));
913
914 if (wrote_final()) {
915 // This method (which must be a constructor by the rules of Java)
916 // wrote a final. The effects of all initializations must be
917 // committed to memory before any code after the constructor
918 // publishes the reference to the newly constructor object.
919 // Rather than wait for the publication, we simply block the
920 // writes here. Rather than put a barrier on only those writes
921 // which are required to complete, we force all writes to complete.
922 //
923 // "All bets are off" unless the first publication occurs after a
924 // normal return from the constructor. We do not attempt to detect
925 // such unusual early publications. But no barrier is needed on
926 // exceptional returns, since they cannot publish normally.
927 //
928 _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
929 #ifndef PRODUCT
930 if (PrintOpto && (Verbose || WizardMode)) {
931 method()->print_name();
932 tty->print_cr(" writes finals and needs a memory barrier");
933 }
934 #endif
935 }
936
937 for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
938 // transform each slice of the original memphi:
939 mms.set_memory(_gvn.transform(mms.memory()));
940 }
941
942 if (tf()->range()->cnt() > TypeFunc::Parms) {
943 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
944 Node* ret_phi = _gvn.transform( _exits.argument(0) );
945 assert(_exits.control()->is_top() || !_gvn.type(ret_phi)->empty(), "return value must be well defined");
946 _exits.push_node(ret_type->basic_type(), ret_phi);
947 }
948
949 // Note: Logic for creating and optimizing the ReturnNode is in Compile.
950
951 // Unlock along the exceptional paths.
952 // This is done late so that we can common up equivalent exceptions
953 // (e.g., null checks) arising from multiple points within this method.
954 // See GraphKit::add_exception_state, which performs the commoning.
955 bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
956
957 // record exit from a method if compiled while Dtrace is turned on.
958 if (do_synch || C->env()->dtrace_method_probes()) {
959 // First move the exception list out of _exits:
960 GraphKit kit(_exits.transfer_exceptions_into_jvms());
961 SafePointNode* normal_map = kit.map(); // keep this guy safe
962 // Now re-collect the exceptions into _exits:
963 SafePointNode* ex_map;
964 while ((ex_map = kit.pop_exception_state()) != NULL) {
965 Node* ex_oop = kit.use_exception_state(ex_map);
966 // Force the exiting JVM state to have this method at InvocationEntryBci.
967 // The exiting JVM state is otherwise a copy of the calling JVMS.
968 JVMState* caller = kit.jvms();
969 JVMState* ex_jvms = caller->clone_shallow(C);
970 ex_jvms->set_map(kit.clone_map());
971 ex_jvms->map()->set_jvms(ex_jvms);
972 ex_jvms->set_bci( InvocationEntryBci);
973 kit.set_jvms(ex_jvms);
974 if (do_synch) {
975 // Add on the synchronized-method box/object combo
976 kit.map()->push_monitor(_synch_lock);
977 // Unlock!
978 kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
979 }
980 if (C->env()->dtrace_method_probes()) {
981 kit.make_dtrace_method_exit(method());
982 }
983 // Done with exception-path processing.
984 ex_map = kit.make_exception_state(ex_oop);
985 assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
986 // Pop the last vestige of this method:
987 ex_map->set_jvms(caller->clone_shallow(C));
988 ex_map->jvms()->set_map(ex_map);
989 _exits.push_exception_state(ex_map);
990 }
991 assert(_exits.map() == normal_map, "keep the same return state");
992 }
993
994 {
995 // Capture very early exceptions (receiver null checks) from caller JVMS
996 GraphKit caller(_caller);
997 SafePointNode* ex_map;
998 while ((ex_map = caller.pop_exception_state()) != NULL) {
999 _exits.add_exception_state(ex_map);
1000 }
1001 }
1002 }
1003
1004 //-----------------------------create_entry_map-------------------------------
1005 // Initialize our parser map to contain the types at method entry.
1006 // For OSR, the map contains a single RawPtr parameter.
1007 // Initial monitor locking for sync. methods is performed by do_method_entry.
1008 SafePointNode* Parse::create_entry_map() {
1009 // Check for really stupid bail-out cases.
1010 uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1011 if (len >= 32760) {
1012 C->record_method_not_compilable_all_tiers("too many local variables");
1013 return NULL;
1014 }
1015
1016 // If this is an inlined method, we may have to do a receiver null check.
1017 if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1018 GraphKit kit(_caller);
1019 kit.null_check_receiver_before_call(method());
1020 _caller = kit.transfer_exceptions_into_jvms();
1021 if (kit.stopped()) {
1022 _exits.add_exception_states_from(_caller);
1023 _exits.set_jvms(_caller);
1024 return NULL;
1025 }
1026 }
1027
1028 assert(method() != NULL, "parser must have a method");
1029
1030 // Create an initial safepoint to hold JVM state during parsing
1031 JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1032 set_map(new (C) SafePointNode(len, jvms));
1033 jvms->set_map(map());
1034 record_for_igvn(map());
1035 assert(jvms->endoff() == len, "correct jvms sizing");
1036
1037 SafePointNode* inmap = _caller->map();
1038 assert(inmap != NULL, "must have inmap");
1039
1040 uint i;
1041
1042 // Pass thru the predefined input parameters.
1043 for (i = 0; i < TypeFunc::Parms; i++) {
1044 map()->init_req(i, inmap->in(i));
1045 }
1046
1047 if (depth() == 1) {
1048 assert(map()->memory()->Opcode() == Op_Parm, "");
1049 // Insert the memory aliasing node
1050 set_all_memory(reset_memory());
1051 }
1052 assert(merged_memory(), "");
1053
1054 // Now add the locals which are initially bound to arguments:
1055 uint arg_size = tf()->domain()->cnt();
1056 ensure_stack(arg_size - TypeFunc::Parms); // OSR methods have funny args
1057 for (i = TypeFunc::Parms; i < arg_size; i++) {
1058 map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1059 }
1060
1061 // Clear out the rest of the map (locals and stack)
1062 for (i = arg_size; i < len; i++) {
1063 map()->init_req(i, top());
1064 }
1065
1066 SafePointNode* entry_map = stop();
1067 return entry_map;
1068 }
1069
1070 //-----------------------------do_method_entry--------------------------------
1071 // Emit any code needed in the pseudo-block before BCI zero.
1072 // The main thing to do is lock the receiver of a synchronized method.
1073 void Parse::do_method_entry() {
1074 set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1075 set_sp(0); // Java Stack Pointer
1076
1077 NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1078
1079 if (C->env()->dtrace_method_probes()) {
1080 make_dtrace_method_entry(method());
1081 }
1082
1083 // If the method is synchronized, we need to construct a lock node, attach
1084 // it to the Start node, and pin it there.
1085 if (method()->is_synchronized()) {
1086 // Insert a FastLockNode right after the Start which takes as arguments
1087 // the current thread pointer, the "this" pointer & the address of the
1088 // stack slot pair used for the lock. The "this" pointer is a projection
1089 // off the start node, but the locking spot has to be constructed by
1090 // creating a ConLNode of 0, and boxing it with a BoxLockNode. The BoxLockNode
1091 // becomes the second argument to the FastLockNode call. The
1092 // FastLockNode becomes the new control parent to pin it to the start.
1093
1094 // Setup Object Pointer
1095 Node *lock_obj = NULL;
1096 if(method()->is_static()) {
1097 ciInstance* mirror = _method->holder()->java_mirror();
1098 const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1099 lock_obj = makecon(t_lock);
1100 } else { // Else pass the "this" pointer,
1101 lock_obj = local(0); // which is Parm0 from StartNode
1102 }
1103 // Clear out dead values from the debug info.
1104 kill_dead_locals();
1105 // Build the FastLockNode
1106 _synch_lock = shared_lock(lock_obj);
1107 }
1108
1109 // Feed profiling data for parameters to the type system so it can
1110 // propagate it as speculative types
1111 record_profiled_parameters_for_speculation();
1112
1113 if (depth() == 1) {
1114 increment_and_test_invocation_counter(Tier2CompileThreshold);
1115 }
1116 }
1117
1118 //------------------------------init_blocks------------------------------------
1119 // Initialize our parser map to contain the types/monitors at method entry.
1120 void Parse::init_blocks() {
1121 // Create the blocks.
1122 _block_count = flow()->block_count();
1123 _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
1124 Copy::zero_to_bytes(_blocks, sizeof(Block)*_block_count);
1125
1126 int rpo;
1127
1128 // Initialize the structs.
1129 for (rpo = 0; rpo < block_count(); rpo++) {
1130 Block* block = rpo_at(rpo);
1131 block->init_node(this, rpo);
1132 }
1133
1134 // Collect predecessor and successor information.
1135 for (rpo = 0; rpo < block_count(); rpo++) {
1136 Block* block = rpo_at(rpo);
1137 block->init_graph(this);
1138 }
1139 }
1140
1141 //-------------------------------init_node-------------------------------------
1142 void Parse::Block::init_node(Parse* outer, int rpo) {
1143 _flow = outer->flow()->rpo_at(rpo);
1144 _pred_count = 0;
1145 _preds_parsed = 0;
1146 _count = 0;
1147 assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
1148 assert(!(is_merged() || is_parsed() || is_handler() || has_merged_backedge()), "sanity");
1149 assert(_live_locals.size() == 0, "sanity");
1150
1151 // entry point has additional predecessor
1152 if (flow()->is_start()) _pred_count++;
1153 assert(flow()->is_start() == (this == outer->start_block()), "");
1154 }
1155
1156 //-------------------------------init_graph------------------------------------
1157 void Parse::Block::init_graph(Parse* outer) {
1158 // Create the successor list for this parser block.
1159 GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
1160 GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
1161 int ns = tfs->length();
1162 int ne = tfe->length();
1163 _num_successors = ns;
1164 _all_successors = ns+ne;
1165 _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
1166 int p = 0;
1167 for (int i = 0; i < ns+ne; i++) {
1168 ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
1169 Block* block2 = outer->rpo_at(tf2->rpo());
1170 _successors[i] = block2;
1171
1172 // Accumulate pred info for the other block, too.
1173 if (i < ns) {
1174 block2->_pred_count++;
1175 } else {
1176 block2->_is_handler = true;
1177 }
1178
1179 #ifdef ASSERT
1180 // A block's successors must be distinguishable by BCI.
1181 // That is, no bytecode is allowed to branch to two different
1182 // clones of the same code location.
1183 for (int j = 0; j < i; j++) {
1184 Block* block1 = _successors[j];
1185 if (block1 == block2) continue; // duplicates are OK
1186 assert(block1->start() != block2->start(), "successors have unique bcis");
1187 }
1188 #endif
1189 }
1190
1191 // Note: We never call next_path_num along exception paths, so they
1192 // never get processed as "ready". Also, the input phis of exception
1193 // handlers get specially processed, so that
1194 }
1195
1196 //---------------------------successor_for_bci---------------------------------
1197 Parse::Block* Parse::Block::successor_for_bci(int bci) {
1198 for (int i = 0; i < all_successors(); i++) {
1199 Block* block2 = successor_at(i);
1200 if (block2->start() == bci) return block2;
1201 }
1202 // We can actually reach here if ciTypeFlow traps out a block
1203 // due to an unloaded class, and concurrently with compilation the
1204 // class is then loaded, so that a later phase of the parser is
1205 // able to see more of the bytecode CFG. Or, the flow pass and
1206 // the parser can have a minor difference of opinion about executability
1207 // of bytecodes. For example, "obj.field = null" is executable even
1208 // if the field's type is an unloaded class; the flow pass used to
1209 // make a trap for such code.
1210 return NULL;
1211 }
1212
1213
1214 //-----------------------------stack_type_at-----------------------------------
1215 const Type* Parse::Block::stack_type_at(int i) const {
1216 return get_type(flow()->stack_type_at(i));
1217 }
1218
1219
1220 //-----------------------------local_type_at-----------------------------------
1221 const Type* Parse::Block::local_type_at(int i) const {
1222 // Make dead locals fall to bottom.
1223 if (_live_locals.size() == 0) {
1224 MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
1225 // This bitmap can be zero length if we saw a breakpoint.
1226 // In such cases, pretend they are all live.
1227 ((Block*)this)->_live_locals = live_locals;
1228 }
1229 if (_live_locals.size() > 0 && !_live_locals.at(i))
1230 return Type::BOTTOM;
1231
1232 return get_type(flow()->local_type_at(i));
1233 }
1234
1235
1236 #ifndef PRODUCT
1237
1238 //----------------------------name_for_bc--------------------------------------
1239 // helper method for BytecodeParseHistogram
1240 static const char* name_for_bc(int i) {
1241 return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
1242 }
1243
1244 //----------------------------BytecodeParseHistogram------------------------------------
1245 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
1246 _parser = p;
1247 _compiler = c;
1248 if( ! _initialized ) { _initialized = true; reset(); }
1249 }
1250
1251 //----------------------------current_count------------------------------------
1252 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
1253 switch( bph_type ) {
1254 case BPH_transforms: { return _parser->gvn().made_progress(); }
1255 case BPH_values: { return _parser->gvn().made_new_values(); }
1256 default: { ShouldNotReachHere(); return 0; }
1257 }
1258 }
1259
1260 //----------------------------initialized--------------------------------------
1261 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
1262
1263 //----------------------------reset--------------------------------------------
1264 void Parse::BytecodeParseHistogram::reset() {
1265 int i = Bytecodes::number_of_codes;
1266 while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
1267 }
1268
1269 //----------------------------set_initial_state--------------------------------
1270 // Record info when starting to parse one bytecode
1271 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
1272 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1273 _initial_bytecode = bc;
1274 _initial_node_count = _compiler->unique();
1275 _initial_transforms = current_count(BPH_transforms);
1276 _initial_values = current_count(BPH_values);
1277 }
1278 }
1279
1280 //----------------------------record_change--------------------------------
1281 // Record results of parsing one bytecode
1282 void Parse::BytecodeParseHistogram::record_change() {
1283 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1284 ++_bytecodes_parsed[_initial_bytecode];
1285 _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
1286 _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
1287 _new_values [_initial_bytecode] += (current_count(BPH_values) - _initial_values);
1288 }
1289 }
1290
1291
1292 //----------------------------print--------------------------------------------
1293 void Parse::BytecodeParseHistogram::print(float cutoff) {
1294 ResourceMark rm;
1295 // print profile
1296 int total = 0;
1297 int i = 0;
1298 for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
1299 int abs_sum = 0;
1300 tty->cr(); //0123456789012345678901234567890123456789012345678901234567890123456789
1301 tty->print_cr("Histogram of %d parsed bytecodes:", total);
1302 if( total == 0 ) { return; }
1303 tty->cr();
1304 tty->print_cr("absolute: count of compiled bytecodes of this type");
1305 tty->print_cr("relative: percentage contribution to compiled nodes");
1306 tty->print_cr("nodes : Average number of nodes constructed per bytecode");
1307 tty->print_cr("rnodes : Significance towards total nodes constructed, (nodes*relative)");
1308 tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
1309 tty->print_cr("values : Average number of node values improved per bytecode");
1310 tty->print_cr("name : Bytecode name");
1311 tty->cr();
1312 tty->print_cr(" absolute relative nodes rnodes transforms values name");
1313 tty->print_cr("----------------------------------------------------------------------");
1314 while (--i > 0) {
1315 int abs = _bytecodes_parsed[i];
1316 float rel = abs * 100.0F / total;
1317 float nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
1318 float rnodes = _bytecodes_parsed[i] == 0 ? 0 : rel * nodes;
1319 float xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
1320 float values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values [i])/_bytecodes_parsed[i];
1321 if (cutoff <= rel) {
1322 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));
1323 abs_sum += abs;
1324 }
1325 }
1326 tty->print_cr("----------------------------------------------------------------------");
1327 float rel_sum = abs_sum * 100.0F / total;
1328 tty->print_cr("%10d %7.2f%% (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
1329 tty->print_cr("----------------------------------------------------------------------");
1330 tty->cr();
1331 }
1332 #endif
1333
1334 //----------------------------load_state_from----------------------------------
1335 // Load block/map/sp. But not do not touch iter/bci.
1336 void Parse::load_state_from(Block* block) {
1337 set_block(block);
1338 // load the block's JVM state:
1339 set_map(block->start_map());
1340 set_sp( block->start_sp());
1341 }
1342
1343
1344 //-----------------------------record_state------------------------------------
1345 void Parse::Block::record_state(Parse* p) {
1346 assert(!is_merged(), "can only record state once, on 1st inflow");
1347 assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
1348 set_start_map(p->stop());
1349 }
1350
1351
1352 //------------------------------do_one_block-----------------------------------
1353 void Parse::do_one_block() {
1354 if (TraceOptoParse) {
1355 Block *b = block();
1356 int ns = b->num_successors();
1357 int nt = b->all_successors();
1358
1359 tty->print("Parsing block #%d at bci [%d,%d), successors: ",
1360 block()->rpo(), block()->start(), block()->limit());
1361 for (int i = 0; i < nt; i++) {
1362 tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
1363 }
1364 if (b->is_loop_head()) tty->print(" lphd");
1365 tty->print_cr("");
1366 }
1367
1368 assert(block()->is_merged(), "must be merged before being parsed");
1369 block()->mark_parsed();
1370 ++_blocks_parsed;
1371
1372 // Set iterator to start of block.
1373 iter().reset_to_bci(block()->start());
1374
1375 CompileLog* log = C->log();
1376
1377 // Parse bytecodes
1378 while (!stopped() && !failing()) {
1379 iter().next();
1380
1381 // Learn the current bci from the iterator:
1382 set_parse_bci(iter().cur_bci());
1383
1384 if (bci() == block()->limit()) {
1385 // Do not walk into the next block until directed by do_all_blocks.
1386 merge(bci());
1387 break;
1388 }
1389 assert(bci() < block()->limit(), "bci still in block");
1390
1391 if (log != NULL) {
1392 // Output an optional context marker, to help place actions
1393 // that occur during parsing of this BC. If there is no log
1394 // output until the next context string, this context string
1395 // will be silently ignored.
1396 log->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
1397 }
1398
1399 if (block()->has_trap_at(bci())) {
1400 // We must respect the flow pass's traps, because it will refuse
1401 // to produce successors for trapping blocks.
1402 int trap_index = block()->flow()->trap_index();
1403 assert(trap_index != 0, "trap index must be valid");
1404 uncommon_trap(trap_index);
1405 break;
1406 }
1407
1408 NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1409
1410 #ifdef ASSERT
1411 int pre_bc_sp = sp();
1412 int inputs, depth;
1413 bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1414 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));
1415 #endif //ASSERT
1416
1417 do_one_bytecode();
1418
1419 assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
1420 err_msg_res("incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth));
1421
1422 do_exceptions();
1423
1424 NOT_PRODUCT( parse_histogram()->record_change(); );
1425
1426 if (log != NULL)
1427 log->clear_context(); // skip marker if nothing was printed
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
1531 int current_bci = bci();
1532 set_parse_bci(target->start()); // Set target bci
1533 if (target->is_SEL_head()) {
1534 DEBUG_ONLY( target->mark_merged_backedge(block()); )
1535 if (target->start() == 0) {
1536 // Add loop predicate for the special case when
1537 // there are backbranches to the method entry.
1538 add_predicate();
1539 }
1540 }
1541 // Add a Region to start the new basic block. Phis will be added
1542 // later lazily.
1543 int edges = target->pred_count();
1544 if (edges < pnum) edges = pnum; // might be a new path!
1545 RegionNode *r = new (C) RegionNode(edges+1);
1546 gvn().set_type(r, Type::CONTROL);
1547 record_for_igvn(r);
1548 // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1549 // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1550 r->init_req(pnum, control());
1551 set_control(r);
1552 set_parse_bci(current_bci); // Restore bci
1553 }
1554
1555 // Convert the existing Parser mapping into a mapping at this bci.
1556 store_state_to(target);
1557 assert(target->is_merged(), "do not come here twice");
1558
1559 } else { // Prior mapping at this bci
1560 if (TraceOptoParse) { tty->print(" with previous state"); }
1561 #ifdef ASSERT
1562 if (target->is_SEL_head()) {
1563 target->mark_merged_backedge(block());
1564 }
1565 #endif
1566 // We must not manufacture more phis if the target is already parsed.
1567 bool nophi = target->is_parsed();
1568
1569 SafePointNode* newin = map();// Hang on to incoming mapping
1570 Block* save_block = block(); // Hang on to incoming block;
1571 load_state_from(target); // Get prior mapping
1572
1573 assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1574 assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1575 assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1576 assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1577
1578 // Iterate over my current mapping and the old mapping.
1579 // Where different, insert Phi functions.
1580 // Use any existing Phi functions.
1581 assert(control()->is_Region(), "must be merging to a region");
1582 RegionNode* r = control()->as_Region();
1583
1584 // Compute where to merge into
1585 // Merge incoming control path
1586 r->init_req(pnum, newin->control());
1587
1588 if (pnum == 1) { // Last merge for this Region?
1589 if (!block()->flow()->is_irreducible_entry()) {
1590 Node* result = _gvn.transform_no_reclaim(r);
1591 if (r != result && TraceOptoParse) {
1592 tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1593 }
1594 }
1595 record_for_igvn(r);
1596 }
1597
1598 // Update all the non-control inputs to map:
1599 assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1600 bool check_elide_phi = target->is_SEL_backedge(save_block);
1601 for (uint j = 1; j < newin->req(); j++) {
1602 Node* m = map()->in(j); // Current state of target.
1603 Node* n = newin->in(j); // Incoming change to target state.
1604 PhiNode* phi;
1605 if (m->is_Phi() && m->as_Phi()->region() == r)
1606 phi = m->as_Phi();
1607 else
1608 phi = NULL;
1609 if (m != n) { // Different; must merge
1610 switch (j) {
1611 // Frame pointer and Return Address never changes
1612 case TypeFunc::FramePtr:// Drop m, use the original value
1613 case TypeFunc::ReturnAdr:
1614 break;
1615 case TypeFunc::Memory: // Merge inputs to the MergeMem node
1616 assert(phi == NULL, "the merge contains phis, not vice versa");
1617 merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1618 continue;
1619 default: // All normal stuff
1620 if (phi == NULL) {
1621 const JVMState* jvms = map()->jvms();
1622 if (EliminateNestedLocks &&
1623 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1624 // BoxLock nodes are not commoning.
1625 // Use old BoxLock node as merged box.
1626 assert(newin->jvms()->is_monitor_box(j), "sanity");
1627 // This assert also tests that nodes are BoxLock.
1628 assert(BoxLockNode::same_slot(n, m), "sanity");
1629 C->gvn_replace_by(n, m);
1630 } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1631 phi = ensure_phi(j, nophi);
1632 }
1633 }
1634 break;
1635 }
1636 }
1637 // At this point, n might be top if:
1638 // - there is no phi (because TypeFlow detected a conflict), or
1639 // - the corresponding control edges is top (a dead incoming path)
1640 // It is a bug if we create a phi which sees a garbage value on a live path.
1641
1642 if (phi != NULL) {
1643 assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1644 assert(phi->region() == r, "");
1645 phi->set_req(pnum, n); // Then add 'n' to the merge
1646 if (pnum == PhiNode::Input) {
1647 // Last merge for this Phi.
1648 // So far, Phis have had a reasonable type from ciTypeFlow.
1649 // Now _gvn will join that with the meet of current inputs.
1650 // BOTTOM is never permissible here, 'cause pessimistically
1651 // Phis of pointers cannot lose the basic pointer type.
1652 debug_only(const Type* bt1 = phi->bottom_type());
1653 assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1654 map()->set_req(j, _gvn.transform_no_reclaim(phi));
1655 debug_only(const Type* bt2 = phi->bottom_type());
1656 assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
1657 record_for_igvn(phi);
1658 }
1659 }
1660 } // End of for all values to be merged
1661
1662 if (pnum == PhiNode::Input &&
1663 !r->in(0)) { // The occasional useless Region
1664 assert(control() == r, "");
1665 set_control(r->nonnull_req());
1666 }
1667
1668 // newin has been subsumed into the lazy merge, and is now dead.
1669 set_block(save_block);
1670
1671 stop(); // done with this guy, for now
1672 }
1673
1674 if (TraceOptoParse) {
1675 tty->print_cr(" on path %d", pnum);
1676 }
1677
1678 // Done with this parser state.
1679 assert(stopped(), "");
1680 }
1681
1682
1683 //--------------------------merge_memory_edges---------------------------------
1684 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1685 // (nophi means we must not create phis, because we already parsed here)
1686 assert(n != NULL, "");
1687 // Merge the inputs to the MergeMems
1688 MergeMemNode* m = merged_memory();
1689
1690 assert(control()->is_Region(), "must be merging to a region");
1691 RegionNode* r = control()->as_Region();
1692
1693 PhiNode* base = NULL;
1694 MergeMemNode* remerge = NULL;
1695 for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1696 Node *p = mms.force_memory();
1697 Node *q = mms.memory2();
1698 if (mms.is_empty() && nophi) {
1699 // Trouble: No new splits allowed after a loop body is parsed.
1700 // Instead, wire the new split into a MergeMem on the backedge.
1701 // The optimizer will sort it out, slicing the phi.
1702 if (remerge == NULL) {
1703 assert(base != NULL, "");
1704 assert(base->in(0) != NULL, "should not be xformed away");
1705 remerge = MergeMemNode::make(C, base->in(pnum));
1706 gvn().set_type(remerge, Type::MEMORY);
1707 base->set_req(pnum, remerge);
1708 }
1709 remerge->set_memory_at(mms.alias_idx(), q);
1710 continue;
1711 }
1712 assert(!q->is_MergeMem(), "");
1713 PhiNode* phi;
1714 if (p != q) {
1715 phi = ensure_memory_phi(mms.alias_idx(), nophi);
1716 } else {
1717 if (p->is_Phi() && p->as_Phi()->region() == r)
1718 phi = p->as_Phi();
1719 else
1720 phi = NULL;
1721 }
1722 // Insert q into local phi
1723 if (phi != NULL) {
1724 assert(phi->region() == r, "");
1725 p = phi;
1726 phi->set_req(pnum, q);
1727 if (mms.at_base_memory()) {
1728 base = phi; // delay transforming it
1729 } else if (pnum == 1) {
1730 record_for_igvn(phi);
1731 p = _gvn.transform_no_reclaim(phi);
1732 }
1733 mms.set_memory(p);// store back through the iterator
1734 }
1735 }
1736 // Transform base last, in case we must fiddle with remerging.
1737 if (base != NULL && pnum == 1) {
1738 record_for_igvn(base);
1739 m->set_base_memory( _gvn.transform_no_reclaim(base) );
1740 }
1741 }
1742
1743
1744 //------------------------ensure_phis_everywhere-------------------------------
1745 void Parse::ensure_phis_everywhere() {
1746 ensure_phi(TypeFunc::I_O);
1747
1748 // Ensure a phi on all currently known memories.
1749 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
1750 ensure_memory_phi(mms.alias_idx());
1751 debug_only(mms.set_memory()); // keep the iterator happy
1752 }
1753
1754 // Note: This is our only chance to create phis for memory slices.
1755 // If we miss a slice that crops up later, it will have to be
1756 // merged into the base-memory phi that we are building here.
1757 // Later, the optimizer will comb out the knot, and build separate
1758 // phi-loops for each memory slice that matters.
1759
1760 // Monitors must nest nicely and not get confused amongst themselves.
1761 // Phi-ify everything up to the monitors, though.
1762 uint monoff = map()->jvms()->monoff();
1763 uint nof_monitors = map()->jvms()->nof_monitors();
1764
1765 assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
1766 bool check_elide_phi = block()->is_SEL_head();
1767 for (uint i = TypeFunc::Parms; i < monoff; i++) {
1768 if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
1769 ensure_phi(i);
1770 }
1771 }
1772
1773 // Even monitors need Phis, though they are well-structured.
1774 // This is true for OSR methods, and also for the rare cases where
1775 // a monitor object is the subject of a replace_in_map operation.
1776 // See bugs 4426707 and 5043395.
1777 for (uint m = 0; m < nof_monitors; m++) {
1778 ensure_phi(map()->jvms()->monitor_obj_offset(m));
1779 }
1780 }
1781
1782
1783 //-----------------------------add_new_path------------------------------------
1784 // Add a previously unaccounted predecessor to this block.
1785 int Parse::Block::add_new_path() {
1786 // If there is no map, return the lowest unused path number.
1787 if (!is_merged()) return pred_count()+1; // there will be a map shortly
1788
1789 SafePointNode* map = start_map();
1790 if (!map->control()->is_Region())
1791 return pred_count()+1; // there may be a region some day
1792 RegionNode* r = map->control()->as_Region();
1793
1794 // Add new path to the region.
1795 uint pnum = r->req();
1796 r->add_req(NULL);
1797
1798 for (uint i = 1; i < map->req(); i++) {
1799 Node* n = map->in(i);
1800 if (i == TypeFunc::Memory) {
1801 // Ensure a phi on all currently known memories.
1802 for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1803 Node* phi = mms.memory();
1804 if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1805 assert(phi->req() == pnum, "must be same size as region");
1806 phi->add_req(NULL);
1807 }
1808 }
1809 } else {
1810 if (n->is_Phi() && n->as_Phi()->region() == r) {
1811 assert(n->req() == pnum, "must be same size as region");
1812 n->add_req(NULL);
1813 }
1814 }
1815 }
1816
1817 return pnum;
1818 }
1819
1820 //------------------------------ensure_phi-------------------------------------
1821 // Turn the idx'th entry of the current map into a Phi
1822 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
1823 SafePointNode* map = this->map();
1824 Node* region = map->control();
1825 assert(region->is_Region(), "");
1826
1827 Node* o = map->in(idx);
1828 assert(o != NULL, "");
1829
1830 if (o == top()) return NULL; // TOP always merges into TOP
1831
1832 if (o->is_Phi() && o->as_Phi()->region() == region) {
1833 return o->as_Phi();
1834 }
1835
1836 // Now use a Phi here for merging
1837 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1838 const JVMState* jvms = map->jvms();
1839 const Type* t;
1840 if (jvms->is_loc(idx)) {
1841 t = block()->local_type_at(idx - jvms->locoff());
1842 } else if (jvms->is_stk(idx)) {
1843 t = block()->stack_type_at(idx - jvms->stkoff());
1844 } else if (jvms->is_mon(idx)) {
1845 assert(!jvms->is_monitor_box(idx), "no phis for boxes");
1846 t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
1847 } else if ((uint)idx < TypeFunc::Parms) {
1848 t = o->bottom_type(); // Type::RETURN_ADDRESS or such-like.
1849 } else {
1850 assert(false, "no type information for this phi");
1851 }
1852
1853 // If the type falls to bottom, then this must be a local that
1854 // is mixing ints and oops or some such. Forcing it to top
1855 // makes it go dead.
1856 if (t == Type::BOTTOM) {
1857 map->set_req(idx, top());
1858 return NULL;
1859 }
1860
1861 // Do not create phis for top either.
1862 // A top on a non-null control flow must be an unused even after the.phi.
1863 if (t == Type::TOP || t == Type::HALF) {
1864 map->set_req(idx, top());
1865 return NULL;
1866 }
1867
1868 PhiNode* phi = PhiNode::make(region, o, t);
1869 gvn().set_type(phi, t);
1870 if (C->do_escape_analysis()) record_for_igvn(phi);
1871 map->set_req(idx, phi);
1872 return phi;
1873 }
1874
1875 //--------------------------ensure_memory_phi----------------------------------
1876 // Turn the idx'th slice of the current memory into a Phi
1877 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
1878 MergeMemNode* mem = merged_memory();
1879 Node* region = control();
1880 assert(region->is_Region(), "");
1881
1882 Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
1883 assert(o != NULL && o != top(), "");
1884
1885 PhiNode* phi;
1886 if (o->is_Phi() && o->as_Phi()->region() == region) {
1887 phi = o->as_Phi();
1888 if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
1889 // clone the shared base memory phi to make a new memory split
1890 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1891 const Type* t = phi->bottom_type();
1892 const TypePtr* adr_type = C->get_adr_type(idx);
1893 phi = phi->slice_memory(adr_type);
1894 gvn().set_type(phi, t);
1895 }
1896 return phi;
1897 }
1898
1899 // Now use a Phi here for merging
1900 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1901 const Type* t = o->bottom_type();
1902 const TypePtr* adr_type = C->get_adr_type(idx);
1903 phi = PhiNode::make(region, o, t, adr_type);
1904 gvn().set_type(phi, t);
1905 if (idx == Compile::AliasIdxBot)
1906 mem->set_base_memory(phi);
1907 else
1908 mem->set_memory_at(idx, phi);
1909 return phi;
1910 }
1911
1912 //------------------------------call_register_finalizer-----------------------
1913 // Check the klass of the receiver and call register_finalizer if the
1914 // class need finalization.
1915 void Parse::call_register_finalizer() {
1916 Node* receiver = local(0);
1917 assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
1918 "must have non-null instance type");
1919
1920 const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
1921 if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
1922 // The type isn't known exactly so see if CHA tells us anything.
1923 ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
1924 if (!Dependencies::has_finalizable_subclass(ik)) {
1925 // No finalizable subclasses so skip the dynamic check.
1926 C->dependencies()->assert_has_no_finalizable_subclasses(ik);
1927 return;
1928 }
1929 }
1930
1931 // Insert a dynamic test for whether the instance needs
1932 // finalization. In general this will fold up since the concrete
1933 // class is often visible so the access flags are constant.
1934 Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
1935 Node* klass = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), klass_addr, TypeInstPtr::KLASS) );
1936
1937 Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
1938 Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT);
1939
1940 Node* mask = _gvn.transform(new (C) AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
1941 Node* check = _gvn.transform(new (C) CmpINode(mask, intcon(0)));
1942 Node* test = _gvn.transform(new (C) BoolNode(check, BoolTest::ne));
1943
1944 IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
1945
1946 RegionNode* result_rgn = new (C) RegionNode(3);
1947 record_for_igvn(result_rgn);
1948
1949 Node *skip_register = _gvn.transform(new (C) IfFalseNode(iff));
1950 result_rgn->init_req(1, skip_register);
1951
1952 Node *needs_register = _gvn.transform(new (C) IfTrueNode(iff));
1953 set_control(needs_register);
1954 if (stopped()) {
1955 // There is no slow path.
1956 result_rgn->init_req(2, top());
1957 } else {
1958 Node *call = make_runtime_call(RC_NO_LEAF,
1959 OptoRuntime::register_finalizer_Type(),
1960 OptoRuntime::register_finalizer_Java(),
1961 NULL, TypePtr::BOTTOM,
1962 receiver);
1963 make_slow_call_ex(call, env()->Throwable_klass(), true);
1964
1965 Node* fast_io = call->in(TypeFunc::I_O);
1966 Node* fast_mem = call->in(TypeFunc::Memory);
1967 // These two phis are pre-filled with copies of of the fast IO and Memory
1968 Node* io_phi = PhiNode::make(result_rgn, fast_io, Type::ABIO);
1969 Node* mem_phi = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
1970
1971 result_rgn->init_req(2, control());
1972 io_phi ->init_req(2, i_o());
1973 mem_phi ->init_req(2, reset_memory());
1974
1975 set_all_memory( _gvn.transform(mem_phi) );
1976 set_i_o( _gvn.transform(io_phi) );
1977 }
1978
1979 set_control( _gvn.transform(result_rgn) );
1980 }
1981
1982 // Add check to deoptimize if RTM state is not ProfileRTM
1983 void Parse::rtm_deopt() {
1984 #if INCLUDE_RTM_OPT
1985 if (C->profile_rtm()) {
1986 assert(C->method() != NULL, "only for normal compilations");
1987 assert(!C->method()->method_data()->is_empty(), "MDO is needed to record RTM state");
1988 assert(depth() == 1, "generate check only for main compiled method");
1989
1990 // Set starting bci for uncommon trap.
1991 set_parse_bci(is_osr_parse() ? osr_bci() : 0);
1992
1993 // Load the rtm_state from the MethodData.
1994 const TypePtr* adr_type = TypeMetadataPtr::make(C->method()->method_data());
1995 Node* mdo = makecon(adr_type);
1996 int offset = MethodData::rtm_state_offset_in_bytes();
1997 Node* adr_node = basic_plus_adr(mdo, mdo, offset);
1998 Node* rtm_state = make_load(control(), adr_node, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
1999
2000 // Separate Load from Cmp by Opaque.
2001 // In expand_macro_nodes() it will be replaced either
2002 // with this load when there are locks in the code
2003 // or with ProfileRTM (cmp->in(2)) otherwise so that
2004 // the check will fold.
2005 Node* profile_state = makecon(TypeInt::make(ProfileRTM));
2006 Node* opq = _gvn.transform( new (C) Opaque3Node(C, rtm_state, Opaque3Node::RTM_OPT) );
2007 Node* chk = _gvn.transform( new (C) CmpINode(opq, profile_state) );
2008 Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
2009 // Branch to failure if state was changed
2010 { BuildCutout unless(this, tst, PROB_ALWAYS);
2011 uncommon_trap(Deoptimization::Reason_rtm_state_change,
2012 Deoptimization::Action_make_not_entrant);
2013 }
2014 }
2015 #endif
2016 }
2017
2018 //------------------------------return_current---------------------------------
2019 // Append current _map to _exit_return
2020 void Parse::return_current(Node* value) {
2021 if (RegisterFinalizersAtInit &&
2022 method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2023 call_register_finalizer();
2024 }
2025
2026 // Do not set_parse_bci, so that return goo is credited to the return insn.
2027 set_bci(InvocationEntryBci);
2028 if (method()->is_synchronized() && GenerateSynchronizationCode) {
2029 shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2030 }
2031 if (C->env()->dtrace_method_probes()) {
2032 make_dtrace_method_exit(method());
2033 }
2034 SafePointNode* exit_return = _exits.map();
2035 exit_return->in( TypeFunc::Control )->add_req( control() );
2036 exit_return->in( TypeFunc::I_O )->add_req( i_o () );
2037 Node *mem = exit_return->in( TypeFunc::Memory );
2038 for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2039 if (mms.is_empty()) {
2040 // get a copy of the base memory, and patch just this one input
2041 const TypePtr* adr_type = mms.adr_type(C);
2042 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2043 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2044 gvn().set_type_bottom(phi);
2045 phi->del_req(phi->req()-1); // prepare to re-patch
2046 mms.set_memory(phi);
2047 }
2048 mms.memory()->add_req(mms.memory2());
2049 }
2050
2051 // frame pointer is always same, already captured
2052 if (value != NULL) {
2053 // If returning oops to an interface-return, there is a silent free
2054 // cast from oop to interface allowed by the Verifier. Make it explicit
2055 // here.
2056 Node* phi = _exits.argument(0);
2057 const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
2058 if( tr && tr->klass()->is_loaded() &&
2059 tr->klass()->is_interface() ) {
2060 const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
2061 if (tp && tp->klass()->is_loaded() &&
2062 !tp->klass()->is_interface()) {
2063 // sharpen the type eagerly; this eases certain assert checking
2064 if (tp->higher_equal(TypeInstPtr::NOTNULL))
2065 tr = tr->join_speculative(TypeInstPtr::NOTNULL)->is_instptr();
2066 value = _gvn.transform(new (C) CheckCastPPNode(0,value,tr));
2067 }
2068 }
2069 phi->add_req(value);
2070 }
2071
2072 stop_and_kill_map(); // This CFG path dies here
2073 }
2074
2075
2076 //------------------------------add_safepoint----------------------------------
2077 void Parse::add_safepoint() {
2078 // See if we can avoid this safepoint. No need for a SafePoint immediately
2079 // after a Call (except Leaf Call) or another SafePoint.
2080 Node *proj = control();
2081 bool add_poll_param = SafePointNode::needs_polling_address_input();
2082 uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2083 if( proj->is_Proj() ) {
2084 Node *n0 = proj->in(0);
2085 if( n0->is_Catch() ) {
2086 n0 = n0->in(0)->in(0);
2087 assert( n0->is_Call(), "expect a call here" );
2088 }
2089 if( n0->is_Call() ) {
2090 if( n0->as_Call()->guaranteed_safepoint() )
2091 return;
2092 } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2093 return;
2094 }
2095 }
2096
2097 // Clear out dead values from the debug info.
2098 kill_dead_locals();
2099
2100 // Clone the JVM State
2101 SafePointNode *sfpnt = new (C) SafePointNode(parms, NULL);
2102
2103 // Capture memory state BEFORE a SafePoint. Since we can block at a
2104 // SafePoint we need our GC state to be safe; i.e. we need all our current
2105 // write barriers (card marks) to not float down after the SafePoint so we
2106 // must read raw memory. Likewise we need all oop stores to match the card
2107 // marks. If deopt can happen, we need ALL stores (we need the correct JVM
2108 // state on a deopt).
2109
2110 // We do not need to WRITE the memory state after a SafePoint. The control
2111 // edge will keep card-marks and oop-stores from floating up from below a
2112 // SafePoint and our true dependency added here will keep them from floating
2113 // down below a SafePoint.
2114
2115 // Clone the current memory state
2116 Node* mem = MergeMemNode::make(C, map()->memory());
2117
2118 mem = _gvn.transform(mem);
2119
2120 // Pass control through the safepoint
2121 sfpnt->init_req(TypeFunc::Control , control());
2122 // Fix edges normally used by a call
2123 sfpnt->init_req(TypeFunc::I_O , top() );
2124 sfpnt->init_req(TypeFunc::Memory , mem );
2125 sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2126 sfpnt->init_req(TypeFunc::FramePtr , top() );
2127
2128 // Create a node for the polling address
2129 if( add_poll_param ) {
2130 Node *polladr = ConPNode::make(C, (address)os::get_polling_page());
2131 sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2132 }
2133
2134 // Fix up the JVM State edges
2135 add_safepoint_edges(sfpnt);
2136 Node *transformed_sfpnt = _gvn.transform(sfpnt);
2137 set_control(transformed_sfpnt);
2138
2139 // Provide an edge from root to safepoint. This makes the safepoint
2140 // appear useful until the parse has completed.
2141 if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2142 assert(C->root() != NULL, "Expect parse is still valid");
2143 C->root()->add_prec(transformed_sfpnt);
2144 }
2145 }
2146
2147 #ifndef PRODUCT
2148 //------------------------show_parse_info--------------------------------------
2149 void Parse::show_parse_info() {
2150 InlineTree* ilt = NULL;
2151 if (C->ilt() != NULL) {
2152 JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2153 ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2154 }
2155 if (PrintCompilation && Verbose) {
2156 if (depth() == 1) {
2157 if( ilt->count_inlines() ) {
2158 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2159 ilt->count_inline_bcs());
2160 tty->cr();
2161 }
2162 } else {
2163 if (method()->is_synchronized()) tty->print("s");
2164 if (method()->has_exception_handlers()) tty->print("!");
2165 // Check this is not the final compiled version
2166 if (C->trap_can_recompile()) {
2167 tty->print("-");
2168 } else {
2169 tty->print(" ");
2170 }
2171 method()->print_short_name();
2172 if (is_osr_parse()) {
2173 tty->print(" @ %d", osr_bci());
2174 }
2175 tty->print(" (%d bytes)",method()->code_size());
2176 if (ilt->count_inlines()) {
2177 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2178 ilt->count_inline_bcs());
2179 }
2180 tty->cr();
2181 }
2182 }
2183 if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2184 // Print that we succeeded; suppress this message on the first osr parse.
2185
2186 if (method()->is_synchronized()) tty->print("s");
2187 if (method()->has_exception_handlers()) tty->print("!");
2188 // Check this is not the final compiled version
2189 if (C->trap_can_recompile() && depth() == 1) {
2190 tty->print("-");
2191 } else {
2192 tty->print(" ");
2193 }
2194 if( depth() != 1 ) { tty->print(" "); } // missing compile count
2195 for (int i = 1; i < depth(); ++i) { tty->print(" "); }
2196 method()->print_short_name();
2197 if (is_osr_parse()) {
2198 tty->print(" @ %d", osr_bci());
2199 }
2200 if (ilt->caller_bci() != -1) {
2201 tty->print(" @ %d", ilt->caller_bci());
2202 }
2203 tty->print(" (%d bytes)",method()->code_size());
2204 if (ilt->count_inlines()) {
2205 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2206 ilt->count_inline_bcs());
2207 }
2208 tty->cr();
2209 }
2210 }
2211
2212
2213 //------------------------------dump-------------------------------------------
2214 // Dump information associated with the bytecodes of current _method
2215 void Parse::dump() {
2216 if( method() != NULL ) {
2217 // Iterate over bytecodes
2218 ciBytecodeStream iter(method());
2219 for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2220 dump_bci( iter.cur_bci() );
2221 tty->cr();
2222 }
2223 }
2224 }
2225
2226 // Dump information associated with a byte code index, 'bci'
2227 void Parse::dump_bci(int bci) {
2228 // Output info on merge-points, cloning, and within _jsr..._ret
2229 // NYI
2230 tty->print(" bci:%d", bci);
2231 }
2232
2233 #endif