1 /*
2 * Copyright (c) 1997, 2020, 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 "memory/resourceArea.hpp"
29 #include "oops/method.hpp"
30 #include "opto/addnode.hpp"
31 #include "opto/c2compiler.hpp"
32 #include "opto/castnode.hpp"
33 #include "opto/idealGraphPrinter.hpp"
34 #include "opto/locknode.hpp"
35 #include "opto/memnode.hpp"
36 #include "opto/opaquenode.hpp"
37 #include "opto/parse.hpp"
38 #include "opto/rootnode.hpp"
39 #include "opto/runtime.hpp"
40 #include "runtime/arguments.hpp"
41 #include "runtime/handles.inline.hpp"
42 #include "runtime/safepointMechanism.hpp"
43 #include "runtime/sharedRuntime.hpp"
44 #include "utilities/bitMap.inline.hpp"
45 #include "utilities/copy.hpp"
46
47 // Static array so we can figure out which bytecodes stop us from compiling
48 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
49 // and eventually should be encapsulated in a proper class (gri 8/18/98).
50
51 #ifndef PRODUCT
52 int nodes_created = 0;
53 int methods_parsed = 0;
54 int methods_seen = 0;
55 int blocks_parsed = 0;
56 int blocks_seen = 0;
57
58 int explicit_null_checks_inserted = 0;
59 int explicit_null_checks_elided = 0;
60 int all_null_checks_found = 0;
61 int implicit_null_checks = 0;
62
63 bool Parse::BytecodeParseHistogram::_initialized = false;
64 uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
65 uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
66 uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
67 uint Parse::BytecodeParseHistogram::_new_values [Bytecodes::number_of_codes];
68
69 //------------------------------print_statistics-------------------------------
print_statistics()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 }
78 tty->print_cr("Blocks parsed: %d Blocks seen: %d", blocks_parsed, blocks_seen);
79
80 if (explicit_null_checks_inserted) {
81 tty->print_cr("%d original NULL checks - %d elided (%2d%%); optimizer leaves %d,",
82 explicit_null_checks_inserted, explicit_null_checks_elided,
83 (100*explicit_null_checks_elided)/explicit_null_checks_inserted,
84 all_null_checks_found);
85 }
86 if (all_null_checks_found) {
87 tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
88 (100*implicit_null_checks)/all_null_checks_found);
89 }
90 if (SharedRuntime::_implicit_null_throws) {
91 tty->print_cr("%d implicit null exceptions at runtime",
92 SharedRuntime::_implicit_null_throws);
93 }
94
95 if (PrintParseStatistics && BytecodeParseHistogram::initialized()) {
96 BytecodeParseHistogram::print();
97 }
98 }
99 #endif
100
101 //------------------------------ON STACK REPLACEMENT---------------------------
102
103 // Construct a node which can be used to get incoming state for
104 // on stack replacement.
fetch_interpreter_state(int index,BasicType bt,Node * local_addrs,Node * local_addrs_base)105 Node *Parse::fetch_interpreter_state(int index,
106 BasicType bt,
107 Node *local_addrs,
108 Node *local_addrs_base) {
109 Node *mem = memory(Compile::AliasIdxRaw);
110 Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
111 Node *ctl = control();
112
113 // Very similar to LoadNode::make, except we handle un-aligned longs and
114 // doubles on Sparc. Intel can handle them just fine directly.
115 Node *l = NULL;
116 switch (bt) { // Signature is flattened
117 case T_INT: l = new LoadINode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInt::INT, MemNode::unordered); break;
118 case T_FLOAT: l = new LoadFNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::FLOAT, MemNode::unordered); break;
119 case T_ADDRESS: l = new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, MemNode::unordered); break;
120 case T_OBJECT: l = new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM, MemNode::unordered); break;
121 case T_LONG:
122 case T_DOUBLE: {
123 // Since arguments are in reverse order, the argument address 'adr'
124 // refers to the back half of the long/double. Recompute adr.
125 adr = basic_plus_adr(local_addrs_base, local_addrs, -(index+1)*wordSize);
126 if (Matcher::misaligned_doubles_ok) {
127 l = (bt == T_DOUBLE)
128 ? (Node*)new LoadDNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::DOUBLE, MemNode::unordered)
129 : (Node*)new LoadLNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeLong::LONG, MemNode::unordered);
130 } else {
131 l = (bt == T_DOUBLE)
132 ? (Node*)new LoadD_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered)
133 : (Node*)new LoadL_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered);
134 }
135 break;
136 }
137 default: ShouldNotReachHere();
138 }
139 return _gvn.transform(l);
140 }
141
142 // Helper routine to prevent the interpreter from handing
143 // unexpected typestate to an OSR method.
144 // The Node l is a value newly dug out of the interpreter frame.
145 // The type is the type predicted by ciTypeFlow. Note that it is
146 // not a general type, but can only come from Type::get_typeflow_type.
147 // The safepoint is a map which will feed an uncommon trap.
check_interpreter_type(Node * l,const Type * type,SafePointNode * & bad_type_exit)148 Node* Parse::check_interpreter_type(Node* l, const Type* type,
149 SafePointNode* &bad_type_exit) {
150
151 const TypeOopPtr* tp = type->isa_oopptr();
152
153 // TypeFlow may assert null-ness if a type appears unloaded.
154 if (type == TypePtr::NULL_PTR ||
155 (tp != NULL && !tp->klass()->is_loaded())) {
156 // Value must be null, not a real oop.
157 Node* chk = _gvn.transform( new CmpPNode(l, null()) );
158 Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
159 IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
160 set_control(_gvn.transform( new IfTrueNode(iff) ));
161 Node* bad_type = _gvn.transform( new IfFalseNode(iff) );
162 bad_type_exit->control()->add_req(bad_type);
163 l = null();
164 }
165
166 // Typeflow can also cut off paths from the CFG, based on
167 // types which appear unloaded, or call sites which appear unlinked.
168 // When paths are cut off, values at later merge points can rise
169 // toward more specific classes. Make sure these specific classes
170 // are still in effect.
171 if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
172 // TypeFlow asserted a specific object type. Value must have that type.
173 Node* bad_type_ctrl = NULL;
174 l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
175 bad_type_exit->control()->add_req(bad_type_ctrl);
176 }
177
178 BasicType bt_l = _gvn.type(l)->basic_type();
179 BasicType bt_t = type->basic_type();
180 assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
181 return l;
182 }
183
184 // Helper routine which sets up elements of the initial parser map when
185 // performing a parse for on stack replacement. Add values into map.
186 // The only parameter contains the address of a interpreter arguments.
load_interpreter_state(Node * osr_buf)187 void Parse::load_interpreter_state(Node* osr_buf) {
188 int index;
189 int max_locals = jvms()->loc_size();
190 int max_stack = jvms()->stk_size();
191
192
193 // Mismatch between method and jvms can occur since map briefly held
194 // an OSR entry state (which takes up one RawPtr word).
195 assert(max_locals == method()->max_locals(), "sanity");
196 assert(max_stack >= method()->max_stack(), "sanity");
197 assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
198 assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
199
200 // Find the start block.
201 Block* osr_block = start_block();
202 assert(osr_block->start() == osr_bci(), "sanity");
203
204 // Set initial BCI.
205 set_parse_bci(osr_block->start());
206
207 // Set initial stack depth.
208 set_sp(osr_block->start_sp());
209
210 // Check bailouts. We currently do not perform on stack replacement
211 // of loops in catch blocks or loops which branch with a non-empty stack.
212 if (sp() != 0) {
213 C->record_method_not_compilable("OSR starts with non-empty stack");
214 return;
215 }
216 // Do not OSR inside finally clauses:
217 if (osr_block->has_trap_at(osr_block->start())) {
218 C->record_method_not_compilable("OSR starts with an immediate trap");
219 return;
220 }
221
222 // Commute monitors from interpreter frame to compiler frame.
223 assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
224 int mcnt = osr_block->flow()->monitor_count();
225 Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
226 for (index = 0; index < mcnt; index++) {
227 // Make a BoxLockNode for the monitor.
228 Node *box = _gvn.transform(new BoxLockNode(next_monitor()));
229
230
231 // Displaced headers and locked objects are interleaved in the
232 // temp OSR buffer. We only copy the locked objects out here.
233 // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
234 Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
235 // Try and copy the displaced header to the BoxNode
236 Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);
237
238
239 store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
240
241 // Build a bogus FastLockNode (no code will be generated) and push the
242 // monitor into our debug info.
243 const FastLockNode *flock = _gvn.transform(new FastLockNode( 0, lock_object, box ))->as_FastLock();
244 map()->push_monitor(flock);
245
246 // If the lock is our method synchronization lock, tuck it away in
247 // _sync_lock for return and rethrow exit paths.
248 if (index == 0 && method()->is_synchronized()) {
249 _synch_lock = flock;
250 }
251 }
252
253 // Use the raw liveness computation to make sure that unexpected
254 // values don't propagate into the OSR frame.
255 MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
256 if (!live_locals.is_valid()) {
257 // Degenerate or breakpointed method.
258 C->record_method_not_compilable("OSR in empty or breakpointed method");
259 return;
260 }
261
262 // Extract the needed locals from the interpreter frame.
263 Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);
264
265 // find all the locals that the interpreter thinks contain live oops
266 const ResourceBitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
267 for (index = 0; index < max_locals; index++) {
268
269 if (!live_locals.at(index)) {
270 continue;
271 }
272
273 const Type *type = osr_block->local_type_at(index);
274
275 if (type->isa_oopptr() != NULL) {
276
277 // 6403625: Verify that the interpreter oopMap thinks that the oop is live
278 // else we might load a stale oop if the MethodLiveness disagrees with the
279 // result of the interpreter. If the interpreter says it is dead we agree
280 // by making the value go to top.
281 //
282
283 if (!live_oops.at(index)) {
284 if (C->log() != NULL) {
285 C->log()->elem("OSR_mismatch local_index='%d'",index);
286 }
287 set_local(index, null());
288 // and ignore it for the loads
289 continue;
290 }
291 }
292
293 // Filter out TOP, HALF, and BOTTOM. (Cf. ensure_phi.)
294 if (type == Type::TOP || type == Type::HALF) {
295 continue;
296 }
297 // If the type falls to bottom, then this must be a local that
298 // is mixing ints and oops or some such. Forcing it to top
299 // makes it go dead.
300 if (type == Type::BOTTOM) {
301 continue;
302 }
303 // Construct code to access the appropriate local.
304 BasicType bt = type->basic_type();
305 if (type == TypePtr::NULL_PTR) {
306 // Ptr types are mixed together with T_ADDRESS but NULL is
307 // really for T_OBJECT types so correct it.
308 bt = T_OBJECT;
309 }
310 Node *value = fetch_interpreter_state(index, bt, locals_addr, osr_buf);
311 set_local(index, value);
312 }
313
314 // Extract the needed stack entries from the interpreter frame.
315 for (index = 0; index < sp(); index++) {
316 const Type *type = osr_block->stack_type_at(index);
317 if (type != Type::TOP) {
318 // Currently the compiler bails out when attempting to on stack replace
319 // at a bci with a non-empty stack. We should not reach here.
320 ShouldNotReachHere();
321 }
322 }
323
324 // End the OSR migration
325 make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
326 CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
327 "OSR_migration_end", TypeRawPtr::BOTTOM,
328 osr_buf);
329
330 // Now that the interpreter state is loaded, make sure it will match
331 // at execution time what the compiler is expecting now:
332 SafePointNode* bad_type_exit = clone_map();
333 bad_type_exit->set_control(new RegionNode(1));
334
335 assert(osr_block->flow()->jsrs()->size() == 0, "should be no jsrs live at osr point");
336 for (index = 0; index < max_locals; index++) {
337 if (stopped()) break;
338 Node* l = local(index);
339 if (l->is_top()) continue; // nothing here
340 const Type *type = osr_block->local_type_at(index);
341 if (type->isa_oopptr() != NULL) {
342 if (!live_oops.at(index)) {
343 // skip type check for dead oops
344 continue;
345 }
346 }
347 if (osr_block->flow()->local_type_at(index)->is_return_address()) {
348 // In our current system it's illegal for jsr addresses to be
349 // live into an OSR entry point because the compiler performs
350 // inlining of jsrs. ciTypeFlow has a bailout that detect this
351 // case and aborts the compile if addresses are live into an OSR
352 // entry point. Because of that we can assume that any address
353 // locals at the OSR entry point are dead. Method liveness
354 // isn't precise enought to figure out that they are dead in all
355 // cases so simply skip checking address locals all
356 // together. Any type check is guaranteed to fail since the
357 // interpreter type is the result of a load which might have any
358 // value and the expected type is a constant.
359 continue;
360 }
361 set_local(index, check_interpreter_type(l, type, bad_type_exit));
362 }
363
364 for (index = 0; index < sp(); index++) {
365 if (stopped()) break;
366 Node* l = stack(index);
367 if (l->is_top()) continue; // nothing here
368 const Type *type = osr_block->stack_type_at(index);
369 set_stack(index, check_interpreter_type(l, type, bad_type_exit));
370 }
371
372 if (bad_type_exit->control()->req() > 1) {
373 // Build an uncommon trap here, if any inputs can be unexpected.
374 bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
375 record_for_igvn(bad_type_exit->control());
376 SafePointNode* types_are_good = map();
377 set_map(bad_type_exit);
378 // The unexpected type happens because a new edge is active
379 // in the CFG, which typeflow had previously ignored.
380 // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
381 // This x will be typed as Integer if notReached is not yet linked.
382 // It could also happen due to a problem in ciTypeFlow analysis.
383 uncommon_trap(Deoptimization::Reason_constraint,
384 Deoptimization::Action_reinterpret);
385 set_map(types_are_good);
386 }
387 }
388
389 //------------------------------Parse------------------------------------------
390 // Main parser constructor.
Parse(JVMState * caller,ciMethod * parse_method,float expected_uses)391 Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses)
392 : _exits(caller)
393 {
394 // Init some variables
395 _caller = caller;
396 _method = parse_method;
397 _expected_uses = expected_uses;
398 _depth = 1 + (caller->has_method() ? caller->depth() : 0);
399 _wrote_final = false;
400 _wrote_volatile = false;
401 _wrote_stable = false;
402 _wrote_fields = false;
403 _alloc_with_final = NULL;
404 _entry_bci = InvocationEntryBci;
405 _tf = NULL;
406 _block = NULL;
407 _first_return = true;
408 _replaced_nodes_for_exceptions = false;
409 _new_idx = C->unique();
410 debug_only(_block_count = -1);
411 debug_only(_blocks = (Block*)-1);
412 #ifndef PRODUCT
413 if (PrintCompilation || PrintOpto) {
414 // Make sure I have an inline tree, so I can print messages about it.
415 JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
416 InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method);
417 }
418 _max_switch_depth = 0;
419 _est_switch_depth = 0;
420 #endif
421
422 if (parse_method->has_reserved_stack_access()) {
423 C->set_has_reserved_stack_access(true);
424 }
425
426 _tf = TypeFunc::make(method());
427 _iter.reset_to_method(method());
428 _flow = method()->get_flow_analysis();
429 if (_flow->failing()) {
430 C->record_method_not_compilable(_flow->failure_reason());
431 }
432
433 #ifndef PRODUCT
434 if (_flow->has_irreducible_entry()) {
435 C->set_parsed_irreducible_loop(true);
436 }
437 #endif
438
439 if (_expected_uses <= 0) {
440 _prof_factor = 1;
441 } else {
442 float prof_total = parse_method->interpreter_invocation_count();
443 if (prof_total <= _expected_uses) {
444 _prof_factor = 1;
445 } else {
446 _prof_factor = _expected_uses / prof_total;
447 }
448 }
449
450 CompileLog* log = C->log();
451 if (log != NULL) {
452 log->begin_head("parse method='%d' uses='%f'",
453 log->identify(parse_method), expected_uses);
454 if (depth() == 1 && C->is_osr_compilation()) {
455 log->print(" osr_bci='%d'", C->entry_bci());
456 }
457 log->stamp();
458 log->end_head();
459 }
460
461 // Accumulate deoptimization counts.
462 // (The range_check and store_check counts are checked elsewhere.)
463 ciMethodData* md = method()->method_data();
464 for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
465 uint md_count = md->trap_count(reason);
466 if (md_count != 0) {
467 if (md_count == md->trap_count_limit())
468 md_count += md->overflow_trap_count();
469 uint total_count = C->trap_count(reason);
470 uint old_count = total_count;
471 total_count += md_count;
472 // Saturate the add if it overflows.
473 if (total_count < old_count || total_count < md_count)
474 total_count = (uint)-1;
475 C->set_trap_count(reason, total_count);
476 if (log != NULL)
477 log->elem("observe trap='%s' count='%d' total='%d'",
478 Deoptimization::trap_reason_name(reason),
479 md_count, total_count);
480 }
481 }
482 // Accumulate total sum of decompilations, also.
483 C->set_decompile_count(C->decompile_count() + md->decompile_count());
484
485 _count_invocations = C->do_count_invocations();
486 _method_data_update = C->do_method_data_update();
487
488 if (log != NULL && method()->has_exception_handlers()) {
489 log->elem("observe that='has_exception_handlers'");
490 }
491
492 assert(InlineTree::check_can_parse(method()) == NULL, "Can not parse this method, cutout earlier");
493 assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
494
495 // Always register dependence if JVMTI is enabled, because
496 // either breakpoint setting or hotswapping of methods may
497 // cause deoptimization.
498 if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
499 C->dependencies()->assert_evol_method(method());
500 }
501
502 NOT_PRODUCT(methods_seen++);
503
504 // Do some special top-level things.
505 if (depth() == 1 && C->is_osr_compilation()) {
506 _entry_bci = C->entry_bci();
507 _flow = method()->get_osr_flow_analysis(osr_bci());
508 if (_flow->failing()) {
509 C->record_method_not_compilable(_flow->failure_reason());
510 #ifndef PRODUCT
511 if (PrintOpto && (Verbose || WizardMode)) {
512 tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
513 if (Verbose) {
514 method()->print();
515 method()->print_codes();
516 _flow->print();
517 }
518 }
519 #endif
520 }
521 _tf = C->tf(); // the OSR entry type is different
522 }
523
524 #ifdef ASSERT
525 if (depth() == 1) {
526 assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
527 } else {
528 assert(!this->is_osr_parse(), "no recursive OSR");
529 }
530 #endif
531
532 #ifndef PRODUCT
533 methods_parsed++;
534 // add method size here to guarantee that inlined methods are added too
535 if (CITime)
536 _total_bytes_compiled += method()->code_size();
537
538 show_parse_info();
539 #endif
540
541 if (failing()) {
542 if (log) log->done("parse");
543 return;
544 }
545
546 gvn().set_type(root(), root()->bottom_type());
547 gvn().transform(top());
548
549 // Import the results of the ciTypeFlow.
550 init_blocks();
551
552 // Merge point for all normal exits
553 build_exits();
554
555 // Setup the initial JVM state map.
556 SafePointNode* entry_map = create_entry_map();
557
558 // Check for bailouts during map initialization
559 if (failing() || entry_map == NULL) {
560 if (log) log->done("parse");
561 return;
562 }
563
564 Node_Notes* caller_nn = C->default_node_notes();
565 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
566 if (DebugInlinedCalls || depth() == 1) {
567 C->set_default_node_notes(make_node_notes(caller_nn));
568 }
569
570 if (is_osr_parse()) {
571 Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
572 entry_map->set_req(TypeFunc::Parms+0, top());
573 set_map(entry_map);
574 load_interpreter_state(osr_buf);
575 } else {
576 set_map(entry_map);
577 do_method_entry();
578 if (depth() == 1 && C->age_code()) {
579 decrement_age();
580 }
581 }
582
583 if (depth() == 1 && !failing()) {
584 if (C->clinit_barrier_on_entry()) {
585 // Add check to deoptimize the nmethod once the holder class is fully initialized
586 clinit_deopt();
587 }
588
589 // Add check to deoptimize the nmethod if RTM state was changed
590 rtm_deopt();
591 }
592
593 // Check for bailouts during method entry or RTM state check setup.
594 if (failing()) {
595 if (log) log->done("parse");
596 C->set_default_node_notes(caller_nn);
597 return;
598 }
599
600 entry_map = map(); // capture any changes performed by method setup code
601 assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
602
603 // We begin parsing as if we have just encountered a jump to the
604 // method entry.
605 Block* entry_block = start_block();
606 assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
607 set_map_clone(entry_map);
608 merge_common(entry_block, entry_block->next_path_num());
609
610 #ifndef PRODUCT
611 BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
612 set_parse_histogram( parse_histogram_obj );
613 #endif
614
615 // Parse all the basic blocks.
616 do_all_blocks();
617
618 C->set_default_node_notes(caller_nn);
619
620 // Check for bailouts during conversion to graph
621 if (failing()) {
622 if (log) log->done("parse");
623 return;
624 }
625
626 // Fix up all exiting control flow.
627 set_map(entry_map);
628 do_exits();
629
630 if (log) log->done("parse nodes='%d' live='%d' memory='" SIZE_FORMAT "'",
631 C->unique(), C->live_nodes(), C->node_arena()->used());
632 }
633
634 //---------------------------do_all_blocks-------------------------------------
do_all_blocks()635 void Parse::do_all_blocks() {
636 bool has_irreducible = flow()->has_irreducible_entry();
637
638 // Walk over all blocks in Reverse Post-Order.
639 while (true) {
640 bool progress = false;
641 for (int rpo = 0; rpo < block_count(); rpo++) {
642 Block* block = rpo_at(rpo);
643
644 if (block->is_parsed()) continue;
645
646 if (!block->is_merged()) {
647 // Dead block, no state reaches this block
648 continue;
649 }
650
651 // Prepare to parse this block.
652 load_state_from(block);
653
654 if (stopped()) {
655 // Block is dead.
656 continue;
657 }
658
659 NOT_PRODUCT(blocks_parsed++);
660
661 progress = true;
662 if (block->is_loop_head() || block->is_handler() || (has_irreducible && !block->is_ready())) {
663 // Not all preds have been parsed. We must build phis everywhere.
664 // (Note that dead locals do not get phis built, ever.)
665 ensure_phis_everywhere();
666
667 if (block->is_SEL_head()) {
668 // Add predicate to single entry (not irreducible) loop head.
669 assert(!block->has_merged_backedge(), "only entry paths should be merged for now");
670 // Predicates may have been added after a dominating if
671 if (!block->has_predicates()) {
672 // Need correct bci for predicate.
673 // It is fine to set it here since do_one_block() will set it anyway.
674 set_parse_bci(block->start());
675 add_empty_predicates();
676 }
677 // Add new region for back branches.
678 int edges = block->pred_count() - block->preds_parsed() + 1; // +1 for original region
679 RegionNode *r = new RegionNode(edges+1);
680 _gvn.set_type(r, Type::CONTROL);
681 record_for_igvn(r);
682 r->init_req(edges, control());
683 set_control(r);
684 // Add new phis.
685 ensure_phis_everywhere();
686 }
687
688 // Leave behind an undisturbed copy of the map, for future merges.
689 set_map(clone_map());
690 }
691
692 if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
693 // In the absence of irreducible loops, the Region and Phis
694 // associated with a merge that doesn't involve a backedge can
695 // be simplified now since the RPO parsing order guarantees
696 // that any path which was supposed to reach here has already
697 // been parsed or must be dead.
698 Node* c = control();
699 Node* result = _gvn.transform_no_reclaim(control());
700 if (c != result && TraceOptoParse) {
701 tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
702 }
703 if (result != top()) {
704 record_for_igvn(result);
705 }
706 }
707
708 // Parse the block.
709 do_one_block();
710
711 // Check for bailouts.
712 if (failing()) return;
713 }
714
715 // with irreducible loops multiple passes might be necessary to parse everything
716 if (!has_irreducible || !progress) {
717 break;
718 }
719 }
720
721 #ifndef PRODUCT
722 blocks_seen += block_count();
723
724 // Make sure there are no half-processed blocks remaining.
725 // Every remaining unprocessed block is dead and may be ignored now.
726 for (int rpo = 0; rpo < block_count(); rpo++) {
727 Block* block = rpo_at(rpo);
728 if (!block->is_parsed()) {
729 if (TraceOptoParse) {
730 tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
731 }
732 assert(!block->is_merged(), "no half-processed blocks");
733 }
734 }
735 #endif
736 }
737
mask_int_value(Node * v,BasicType bt,PhaseGVN * gvn)738 static Node* mask_int_value(Node* v, BasicType bt, PhaseGVN* gvn) {
739 switch (bt) {
740 case T_BYTE:
741 v = gvn->transform(new LShiftINode(v, gvn->intcon(24)));
742 v = gvn->transform(new RShiftINode(v, gvn->intcon(24)));
743 break;
744 case T_SHORT:
745 v = gvn->transform(new LShiftINode(v, gvn->intcon(16)));
746 v = gvn->transform(new RShiftINode(v, gvn->intcon(16)));
747 break;
748 case T_CHAR:
749 v = gvn->transform(new AndINode(v, gvn->intcon(0xFFFF)));
750 break;
751 case T_BOOLEAN:
752 v = gvn->transform(new AndINode(v, gvn->intcon(0x1)));
753 break;
754 default:
755 break;
756 }
757 return v;
758 }
759
760 //-------------------------------build_exits----------------------------------
761 // Build normal and exceptional exit merge points.
build_exits()762 void Parse::build_exits() {
763 // make a clone of caller to prevent sharing of side-effects
764 _exits.set_map(_exits.clone_map());
765 _exits.clean_stack(_exits.sp());
766 _exits.sync_jvms();
767
768 RegionNode* region = new RegionNode(1);
769 record_for_igvn(region);
770 gvn().set_type_bottom(region);
771 _exits.set_control(region);
772
773 // Note: iophi and memphi are not transformed until do_exits.
774 Node* iophi = new PhiNode(region, Type::ABIO);
775 Node* memphi = new PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
776 gvn().set_type_bottom(iophi);
777 gvn().set_type_bottom(memphi);
778 _exits.set_i_o(iophi);
779 _exits.set_all_memory(memphi);
780
781 // Add a return value to the exit state. (Do not push it yet.)
782 if (tf()->range()->cnt() > TypeFunc::Parms) {
783 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
784 if (ret_type->isa_int()) {
785 BasicType ret_bt = method()->return_type()->basic_type();
786 if (ret_bt == T_BOOLEAN ||
787 ret_bt == T_CHAR ||
788 ret_bt == T_BYTE ||
789 ret_bt == T_SHORT) {
790 ret_type = TypeInt::INT;
791 }
792 }
793
794 // Don't "bind" an unloaded return klass to the ret_phi. If the klass
795 // becomes loaded during the subsequent parsing, the loaded and unloaded
796 // types will not join when we transform and push in do_exits().
797 const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
798 if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
799 ret_type = TypeOopPtr::BOTTOM;
800 }
801 int ret_size = type2size[ret_type->basic_type()];
802 Node* ret_phi = new PhiNode(region, ret_type);
803 gvn().set_type_bottom(ret_phi);
804 _exits.ensure_stack(ret_size);
805 assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
806 assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
807 _exits.set_argument(0, ret_phi); // here is where the parser finds it
808 // Note: ret_phi is not yet pushed, until do_exits.
809 }
810 }
811
812
813 //----------------------------build_start_state-------------------------------
814 // Construct a state which contains only the incoming arguments from an
815 // unknown caller. The method & bci will be NULL & InvocationEntryBci.
build_start_state(StartNode * start,const TypeFunc * tf)816 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
817 int arg_size = tf->domain()->cnt();
818 int max_size = MAX2(arg_size, (int)tf->range()->cnt());
819 JVMState* jvms = new (this) JVMState(max_size - TypeFunc::Parms);
820 SafePointNode* map = new SafePointNode(max_size, NULL);
821 record_for_igvn(map);
822 assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
823 Node_Notes* old_nn = default_node_notes();
824 if (old_nn != NULL && has_method()) {
825 Node_Notes* entry_nn = old_nn->clone(this);
826 JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
827 entry_jvms->set_offsets(0);
828 entry_jvms->set_bci(entry_bci());
829 entry_nn->set_jvms(entry_jvms);
830 set_default_node_notes(entry_nn);
831 }
832 uint i;
833 for (i = 0; i < (uint)arg_size; i++) {
834 Node* parm = initial_gvn()->transform(new ParmNode(start, i));
835 map->init_req(i, parm);
836 // Record all these guys for later GVN.
837 record_for_igvn(parm);
838 }
839 for (; i < map->req(); i++) {
840 map->init_req(i, top());
841 }
842 assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
843 set_default_node_notes(old_nn);
844 map->set_jvms(jvms);
845 jvms->set_map(map);
846 return jvms;
847 }
848
849 //-----------------------------make_node_notes---------------------------------
make_node_notes(Node_Notes * caller_nn)850 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
851 if (caller_nn == NULL) return NULL;
852 Node_Notes* nn = caller_nn->clone(C);
853 JVMState* caller_jvms = nn->jvms();
854 JVMState* jvms = new (C) JVMState(method(), caller_jvms);
855 jvms->set_offsets(0);
856 jvms->set_bci(_entry_bci);
857 nn->set_jvms(jvms);
858 return nn;
859 }
860
861
862 //--------------------------return_values--------------------------------------
return_values(JVMState * jvms)863 void Compile::return_values(JVMState* jvms) {
864 GraphKit kit(jvms);
865 Node* ret = new ReturnNode(TypeFunc::Parms,
866 kit.control(),
867 kit.i_o(),
868 kit.reset_memory(),
869 kit.frameptr(),
870 kit.returnadr());
871 // Add zero or 1 return values
872 int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
873 if (ret_size > 0) {
874 kit.inc_sp(-ret_size); // pop the return value(s)
875 kit.sync_jvms();
876 ret->add_req(kit.argument(0));
877 // Note: The second dummy edge is not needed by a ReturnNode.
878 }
879 // bind it to root
880 root()->add_req(ret);
881 record_for_igvn(ret);
882 initial_gvn()->transform_no_reclaim(ret);
883 }
884
885 //------------------------rethrow_exceptions-----------------------------------
886 // Bind all exception states in the list into a single RethrowNode.
rethrow_exceptions(JVMState * jvms)887 void Compile::rethrow_exceptions(JVMState* jvms) {
888 GraphKit kit(jvms);
889 if (!kit.has_exceptions()) return; // nothing to generate
890 // Load my combined exception state into the kit, with all phis transformed:
891 SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
892 Node* ex_oop = kit.use_exception_state(ex_map);
893 RethrowNode* exit = new RethrowNode(kit.control(),
894 kit.i_o(), kit.reset_memory(),
895 kit.frameptr(), kit.returnadr(),
896 // like a return but with exception input
897 ex_oop);
898 // bind to root
899 root()->add_req(exit);
900 record_for_igvn(exit);
901 initial_gvn()->transform_no_reclaim(exit);
902 }
903
904 //---------------------------do_exceptions-------------------------------------
905 // Process exceptions arising from the current bytecode.
906 // Send caught exceptions to the proper handler within this method.
907 // Unhandled exceptions feed into _exit.
do_exceptions()908 void Parse::do_exceptions() {
909 if (!has_exceptions()) return;
910
911 if (failing()) {
912 // Pop them all off and throw them away.
913 while (pop_exception_state() != NULL) ;
914 return;
915 }
916
917 PreserveJVMState pjvms(this, false);
918
919 SafePointNode* ex_map;
920 while ((ex_map = pop_exception_state()) != NULL) {
921 if (!method()->has_exception_handlers()) {
922 // Common case: Transfer control outward.
923 // Doing it this early allows the exceptions to common up
924 // even between adjacent method calls.
925 throw_to_exit(ex_map);
926 } else {
927 // Have to look at the exception first.
928 assert(stopped(), "catch_inline_exceptions trashes the map");
929 catch_inline_exceptions(ex_map);
930 stop_and_kill_map(); // we used up this exception state; kill it
931 }
932 }
933
934 // We now return to our regularly scheduled program:
935 }
936
937 //---------------------------throw_to_exit-------------------------------------
938 // Merge the given map into an exception exit from this method.
939 // The exception exit will handle any unlocking of receiver.
940 // The ex_oop must be saved within the ex_map, unlike merge_exception.
throw_to_exit(SafePointNode * ex_map)941 void Parse::throw_to_exit(SafePointNode* ex_map) {
942 // Pop the JVMS to (a copy of) the caller.
943 GraphKit caller;
944 caller.set_map_clone(_caller->map());
945 caller.set_bci(_caller->bci());
946 caller.set_sp(_caller->sp());
947 // Copy out the standard machine state:
948 for (uint i = 0; i < TypeFunc::Parms; i++) {
949 caller.map()->set_req(i, ex_map->in(i));
950 }
951 if (ex_map->has_replaced_nodes()) {
952 _replaced_nodes_for_exceptions = true;
953 }
954 caller.map()->transfer_replaced_nodes_from(ex_map, _new_idx);
955 // ...and the exception:
956 Node* ex_oop = saved_ex_oop(ex_map);
957 SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
958 // Finally, collect the new exception state in my exits:
959 _exits.add_exception_state(caller_ex_map);
960 }
961
962 //------------------------------do_exits---------------------------------------
do_exits()963 void Parse::do_exits() {
964 set_parse_bci(InvocationEntryBci);
965
966 // Now peephole on the return bits
967 Node* region = _exits.control();
968 _exits.set_control(gvn().transform(region));
969
970 Node* iophi = _exits.i_o();
971 _exits.set_i_o(gvn().transform(iophi));
972
973 // Figure out if we need to emit the trailing barrier. The barrier is only
974 // needed in the constructors, and only in three cases:
975 //
976 // 1. The constructor wrote a final. The effects of all initializations
977 // must be committed to memory before any code after the constructor
978 // publishes the reference to the newly constructed object. Rather
979 // than wait for the publication, we simply block the writes here.
980 // Rather than put a barrier on only those writes which are required
981 // to complete, we force all writes to complete.
982 //
983 // 2. Experimental VM option is used to force the barrier if any field
984 // was written out in the constructor.
985 //
986 // 3. On processors which are not CPU_MULTI_COPY_ATOMIC (e.g. PPC64),
987 // support_IRIW_for_not_multiple_copy_atomic_cpu selects that
988 // MemBarVolatile is used before volatile load instead of after volatile
989 // store, so there's no barrier after the store.
990 // We want to guarantee the same behavior as on platforms with total store
991 // order, although this is not required by the Java memory model.
992 // In this case, we want to enforce visibility of volatile field
993 // initializations which are performed in constructors.
994 // So as with finals, we add a barrier here.
995 //
996 // "All bets are off" unless the first publication occurs after a
997 // normal return from the constructor. We do not attempt to detect
998 // such unusual early publications. But no barrier is needed on
999 // exceptional returns, since they cannot publish normally.
1000 //
1001 if (method()->is_initializer() &&
1002 (wrote_final() ||
1003 (AlwaysSafeConstructors && wrote_fields()) ||
1004 (support_IRIW_for_not_multiple_copy_atomic_cpu && wrote_volatile()))) {
1005 _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
1006
1007 // If Memory barrier is created for final fields write
1008 // and allocation node does not escape the initialize method,
1009 // then barrier introduced by allocation node can be removed.
1010 if (DoEscapeAnalysis && alloc_with_final()) {
1011 AllocateNode *alloc = AllocateNode::Ideal_allocation(alloc_with_final(), &_gvn);
1012 alloc->compute_MemBar_redundancy(method());
1013 }
1014 if (PrintOpto && (Verbose || WizardMode)) {
1015 method()->print_name();
1016 tty->print_cr(" writes finals and needs a memory barrier");
1017 }
1018 }
1019
1020 // Any method can write a @Stable field; insert memory barriers
1021 // after those also. Can't bind predecessor allocation node (if any)
1022 // with barrier because allocation doesn't always dominate
1023 // MemBarRelease.
1024 if (wrote_stable()) {
1025 _exits.insert_mem_bar(Op_MemBarRelease);
1026 if (PrintOpto && (Verbose || WizardMode)) {
1027 method()->print_name();
1028 tty->print_cr(" writes @Stable and needs a memory barrier");
1029 }
1030 }
1031
1032 for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
1033 // transform each slice of the original memphi:
1034 mms.set_memory(_gvn.transform(mms.memory()));
1035 }
1036 // Clean up input MergeMems created by transforming the slices
1037 _gvn.transform(_exits.merged_memory());
1038
1039 if (tf()->range()->cnt() > TypeFunc::Parms) {
1040 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
1041 Node* ret_phi = _gvn.transform( _exits.argument(0) );
1042 if (!_exits.control()->is_top() && _gvn.type(ret_phi)->empty()) {
1043 // If the type we set for the ret_phi in build_exits() is too optimistic and
1044 // the ret_phi is top now, there's an extremely small chance that it may be due to class
1045 // loading. It could also be due to an error, so mark this method as not compilable because
1046 // otherwise this could lead to an infinite compile loop.
1047 // In any case, this code path is rarely (and never in my testing) reached.
1048 C->record_method_not_compilable("Can't determine return type.");
1049 return;
1050 }
1051 if (ret_type->isa_int()) {
1052 BasicType ret_bt = method()->return_type()->basic_type();
1053 ret_phi = mask_int_value(ret_phi, ret_bt, &_gvn);
1054 }
1055 _exits.push_node(ret_type->basic_type(), ret_phi);
1056 }
1057
1058 // Note: Logic for creating and optimizing the ReturnNode is in Compile.
1059
1060 // Unlock along the exceptional paths.
1061 // This is done late so that we can common up equivalent exceptions
1062 // (e.g., null checks) arising from multiple points within this method.
1063 // See GraphKit::add_exception_state, which performs the commoning.
1064 bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
1065
1066 // record exit from a method if compiled while Dtrace is turned on.
1067 if (do_synch || C->env()->dtrace_method_probes() || _replaced_nodes_for_exceptions) {
1068 // First move the exception list out of _exits:
1069 GraphKit kit(_exits.transfer_exceptions_into_jvms());
1070 SafePointNode* normal_map = kit.map(); // keep this guy safe
1071 // Now re-collect the exceptions into _exits:
1072 SafePointNode* ex_map;
1073 while ((ex_map = kit.pop_exception_state()) != NULL) {
1074 Node* ex_oop = kit.use_exception_state(ex_map);
1075 // Force the exiting JVM state to have this method at InvocationEntryBci.
1076 // The exiting JVM state is otherwise a copy of the calling JVMS.
1077 JVMState* caller = kit.jvms();
1078 JVMState* ex_jvms = caller->clone_shallow(C);
1079 ex_jvms->set_map(kit.clone_map());
1080 ex_jvms->map()->set_jvms(ex_jvms);
1081 ex_jvms->set_bci( InvocationEntryBci);
1082 kit.set_jvms(ex_jvms);
1083 if (do_synch) {
1084 // Add on the synchronized-method box/object combo
1085 kit.map()->push_monitor(_synch_lock);
1086 // Unlock!
1087 kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
1088 }
1089 if (C->env()->dtrace_method_probes()) {
1090 kit.make_dtrace_method_exit(method());
1091 }
1092 if (_replaced_nodes_for_exceptions) {
1093 kit.map()->apply_replaced_nodes(_new_idx);
1094 }
1095 // Done with exception-path processing.
1096 ex_map = kit.make_exception_state(ex_oop);
1097 assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
1098 // Pop the last vestige of this method:
1099 ex_map->set_jvms(caller->clone_shallow(C));
1100 ex_map->jvms()->set_map(ex_map);
1101 _exits.push_exception_state(ex_map);
1102 }
1103 assert(_exits.map() == normal_map, "keep the same return state");
1104 }
1105
1106 {
1107 // Capture very early exceptions (receiver null checks) from caller JVMS
1108 GraphKit caller(_caller);
1109 SafePointNode* ex_map;
1110 while ((ex_map = caller.pop_exception_state()) != NULL) {
1111 _exits.add_exception_state(ex_map);
1112 }
1113 }
1114 _exits.map()->apply_replaced_nodes(_new_idx);
1115 }
1116
1117 //-----------------------------create_entry_map-------------------------------
1118 // Initialize our parser map to contain the types at method entry.
1119 // For OSR, the map contains a single RawPtr parameter.
1120 // Initial monitor locking for sync. methods is performed by do_method_entry.
create_entry_map()1121 SafePointNode* Parse::create_entry_map() {
1122 // Check for really stupid bail-out cases.
1123 uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1124 if (len >= 32760) {
1125 C->record_method_not_compilable("too many local variables");
1126 return NULL;
1127 }
1128
1129 // clear current replaced nodes that are of no use from here on (map was cloned in build_exits).
1130 _caller->map()->delete_replaced_nodes();
1131
1132 // If this is an inlined method, we may have to do a receiver null check.
1133 if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1134 GraphKit kit(_caller);
1135 kit.null_check_receiver_before_call(method());
1136 _caller = kit.transfer_exceptions_into_jvms();
1137 if (kit.stopped()) {
1138 _exits.add_exception_states_from(_caller);
1139 _exits.set_jvms(_caller);
1140 return NULL;
1141 }
1142 }
1143
1144 assert(method() != NULL, "parser must have a method");
1145
1146 // Create an initial safepoint to hold JVM state during parsing
1147 JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1148 set_map(new SafePointNode(len, jvms));
1149 jvms->set_map(map());
1150 record_for_igvn(map());
1151 assert(jvms->endoff() == len, "correct jvms sizing");
1152
1153 SafePointNode* inmap = _caller->map();
1154 assert(inmap != NULL, "must have inmap");
1155 // In case of null check on receiver above
1156 map()->transfer_replaced_nodes_from(inmap, _new_idx);
1157
1158 uint i;
1159
1160 // Pass thru the predefined input parameters.
1161 for (i = 0; i < TypeFunc::Parms; i++) {
1162 map()->init_req(i, inmap->in(i));
1163 }
1164
1165 if (depth() == 1) {
1166 assert(map()->memory()->Opcode() == Op_Parm, "");
1167 // Insert the memory aliasing node
1168 set_all_memory(reset_memory());
1169 }
1170 assert(merged_memory(), "");
1171
1172 // Now add the locals which are initially bound to arguments:
1173 uint arg_size = tf()->domain()->cnt();
1174 ensure_stack(arg_size - TypeFunc::Parms); // OSR methods have funny args
1175 for (i = TypeFunc::Parms; i < arg_size; i++) {
1176 map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1177 }
1178
1179 // Clear out the rest of the map (locals and stack)
1180 for (i = arg_size; i < len; i++) {
1181 map()->init_req(i, top());
1182 }
1183
1184 SafePointNode* entry_map = stop();
1185 return entry_map;
1186 }
1187
1188 //-----------------------------do_method_entry--------------------------------
1189 // Emit any code needed in the pseudo-block before BCI zero.
1190 // The main thing to do is lock the receiver of a synchronized method.
do_method_entry()1191 void Parse::do_method_entry() {
1192 set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1193 set_sp(0); // Java Stack Pointer
1194
1195 NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1196
1197 if (C->env()->dtrace_method_probes()) {
1198 make_dtrace_method_entry(method());
1199 }
1200
1201 // If the method is synchronized, we need to construct a lock node, attach
1202 // it to the Start node, and pin it there.
1203 if (method()->is_synchronized()) {
1204 // Insert a FastLockNode right after the Start which takes as arguments
1205 // the current thread pointer, the "this" pointer & the address of the
1206 // stack slot pair used for the lock. The "this" pointer is a projection
1207 // off the start node, but the locking spot has to be constructed by
1208 // creating a ConLNode of 0, and boxing it with a BoxLockNode. The BoxLockNode
1209 // becomes the second argument to the FastLockNode call. The
1210 // FastLockNode becomes the new control parent to pin it to the start.
1211
1212 // Setup Object Pointer
1213 Node *lock_obj = NULL;
1214 if(method()->is_static()) {
1215 ciInstance* mirror = _method->holder()->java_mirror();
1216 const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1217 lock_obj = makecon(t_lock);
1218 } else { // Else pass the "this" pointer,
1219 lock_obj = local(0); // which is Parm0 from StartNode
1220 }
1221 // Clear out dead values from the debug info.
1222 kill_dead_locals();
1223 // Build the FastLockNode
1224 _synch_lock = shared_lock(lock_obj);
1225 }
1226
1227 // Feed profiling data for parameters to the type system so it can
1228 // propagate it as speculative types
1229 record_profiled_parameters_for_speculation();
1230
1231 if (depth() == 1) {
1232 increment_and_test_invocation_counter(Tier2CompileThreshold);
1233 }
1234 }
1235
1236 //------------------------------init_blocks------------------------------------
1237 // Initialize our parser map to contain the types/monitors at method entry.
init_blocks()1238 void Parse::init_blocks() {
1239 // Create the blocks.
1240 _block_count = flow()->block_count();
1241 _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
1242
1243 // Initialize the structs.
1244 for (int rpo = 0; rpo < block_count(); rpo++) {
1245 Block* block = rpo_at(rpo);
1246 new(block) Block(this, rpo);
1247 }
1248
1249 // Collect predecessor and successor information.
1250 for (int rpo = 0; rpo < block_count(); rpo++) {
1251 Block* block = rpo_at(rpo);
1252 block->init_graph(this);
1253 }
1254 }
1255
1256 //-------------------------------init_node-------------------------------------
Block(Parse * outer,int rpo)1257 Parse::Block::Block(Parse* outer, int rpo) : _live_locals() {
1258 _flow = outer->flow()->rpo_at(rpo);
1259 _pred_count = 0;
1260 _preds_parsed = 0;
1261 _count = 0;
1262 _is_parsed = false;
1263 _is_handler = false;
1264 _has_merged_backedge = false;
1265 _start_map = NULL;
1266 _has_predicates = false;
1267 _num_successors = 0;
1268 _all_successors = 0;
1269 _successors = NULL;
1270 assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
1271 assert(!(is_merged() || is_parsed() || is_handler() || has_merged_backedge()), "sanity");
1272 assert(_live_locals.size() == 0, "sanity");
1273
1274 // entry point has additional predecessor
1275 if (flow()->is_start()) _pred_count++;
1276 assert(flow()->is_start() == (this == outer->start_block()), "");
1277 }
1278
1279 //-------------------------------init_graph------------------------------------
init_graph(Parse * outer)1280 void Parse::Block::init_graph(Parse* outer) {
1281 // Create the successor list for this parser block.
1282 GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
1283 GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
1284 int ns = tfs->length();
1285 int ne = tfe->length();
1286 _num_successors = ns;
1287 _all_successors = ns+ne;
1288 _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
1289 int p = 0;
1290 for (int i = 0; i < ns+ne; i++) {
1291 ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
1292 Block* block2 = outer->rpo_at(tf2->rpo());
1293 _successors[i] = block2;
1294
1295 // Accumulate pred info for the other block, too.
1296 // Note: We also need to set _pred_count for exception blocks since they could
1297 // also have normal predecessors (reached without athrow by an explicit jump).
1298 // This also means that next_path_num can be called along exception paths.
1299 block2->_pred_count++;
1300 if (i >= ns) {
1301 block2->_is_handler = true;
1302 }
1303
1304 #ifdef ASSERT
1305 // A block's successors must be distinguishable by BCI.
1306 // That is, no bytecode is allowed to branch to two different
1307 // clones of the same code location.
1308 for (int j = 0; j < i; j++) {
1309 Block* block1 = _successors[j];
1310 if (block1 == block2) continue; // duplicates are OK
1311 assert(block1->start() != block2->start(), "successors have unique bcis");
1312 }
1313 #endif
1314 }
1315 }
1316
1317 //---------------------------successor_for_bci---------------------------------
successor_for_bci(int bci)1318 Parse::Block* Parse::Block::successor_for_bci(int bci) {
1319 for (int i = 0; i < all_successors(); i++) {
1320 Block* block2 = successor_at(i);
1321 if (block2->start() == bci) return block2;
1322 }
1323 // We can actually reach here if ciTypeFlow traps out a block
1324 // due to an unloaded class, and concurrently with compilation the
1325 // class is then loaded, so that a later phase of the parser is
1326 // able to see more of the bytecode CFG. Or, the flow pass and
1327 // the parser can have a minor difference of opinion about executability
1328 // of bytecodes. For example, "obj.field = null" is executable even
1329 // if the field's type is an unloaded class; the flow pass used to
1330 // make a trap for such code.
1331 return NULL;
1332 }
1333
1334
1335 //-----------------------------stack_type_at-----------------------------------
stack_type_at(int i) const1336 const Type* Parse::Block::stack_type_at(int i) const {
1337 return get_type(flow()->stack_type_at(i));
1338 }
1339
1340
1341 //-----------------------------local_type_at-----------------------------------
local_type_at(int i) const1342 const Type* Parse::Block::local_type_at(int i) const {
1343 // Make dead locals fall to bottom.
1344 if (_live_locals.size() == 0) {
1345 MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
1346 // This bitmap can be zero length if we saw a breakpoint.
1347 // In such cases, pretend they are all live.
1348 ((Block*)this)->_live_locals = live_locals;
1349 }
1350 if (_live_locals.size() > 0 && !_live_locals.at(i))
1351 return Type::BOTTOM;
1352
1353 return get_type(flow()->local_type_at(i));
1354 }
1355
1356
1357 #ifndef PRODUCT
1358
1359 //----------------------------name_for_bc--------------------------------------
1360 // helper method for BytecodeParseHistogram
name_for_bc(int i)1361 static const char* name_for_bc(int i) {
1362 return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
1363 }
1364
1365 //----------------------------BytecodeParseHistogram------------------------------------
BytecodeParseHistogram(Parse * p,Compile * c)1366 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
1367 _parser = p;
1368 _compiler = c;
1369 if( ! _initialized ) { _initialized = true; reset(); }
1370 }
1371
1372 //----------------------------current_count------------------------------------
current_count(BPHType bph_type)1373 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
1374 switch( bph_type ) {
1375 case BPH_transforms: { return _parser->gvn().made_progress(); }
1376 case BPH_values: { return _parser->gvn().made_new_values(); }
1377 default: { ShouldNotReachHere(); return 0; }
1378 }
1379 }
1380
1381 //----------------------------initialized--------------------------------------
initialized()1382 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
1383
1384 //----------------------------reset--------------------------------------------
reset()1385 void Parse::BytecodeParseHistogram::reset() {
1386 int i = Bytecodes::number_of_codes;
1387 while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
1388 }
1389
1390 //----------------------------set_initial_state--------------------------------
1391 // Record info when starting to parse one bytecode
set_initial_state(Bytecodes::Code bc)1392 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
1393 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1394 _initial_bytecode = bc;
1395 _initial_node_count = _compiler->unique();
1396 _initial_transforms = current_count(BPH_transforms);
1397 _initial_values = current_count(BPH_values);
1398 }
1399 }
1400
1401 //----------------------------record_change--------------------------------
1402 // Record results of parsing one bytecode
record_change()1403 void Parse::BytecodeParseHistogram::record_change() {
1404 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1405 ++_bytecodes_parsed[_initial_bytecode];
1406 _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
1407 _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
1408 _new_values [_initial_bytecode] += (current_count(BPH_values) - _initial_values);
1409 }
1410 }
1411
1412
1413 //----------------------------print--------------------------------------------
print(float cutoff)1414 void Parse::BytecodeParseHistogram::print(float cutoff) {
1415 ResourceMark rm;
1416 // print profile
1417 int total = 0;
1418 int i = 0;
1419 for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
1420 int abs_sum = 0;
1421 tty->cr(); //0123456789012345678901234567890123456789012345678901234567890123456789
1422 tty->print_cr("Histogram of %d parsed bytecodes:", total);
1423 if( total == 0 ) { return; }
1424 tty->cr();
1425 tty->print_cr("absolute: count of compiled bytecodes of this type");
1426 tty->print_cr("relative: percentage contribution to compiled nodes");
1427 tty->print_cr("nodes : Average number of nodes constructed per bytecode");
1428 tty->print_cr("rnodes : Significance towards total nodes constructed, (nodes*relative)");
1429 tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
1430 tty->print_cr("values : Average number of node values improved per bytecode");
1431 tty->print_cr("name : Bytecode name");
1432 tty->cr();
1433 tty->print_cr(" absolute relative nodes rnodes transforms values name");
1434 tty->print_cr("----------------------------------------------------------------------");
1435 while (--i > 0) {
1436 int abs = _bytecodes_parsed[i];
1437 float rel = abs * 100.0F / total;
1438 float nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
1439 float rnodes = _bytecodes_parsed[i] == 0 ? 0 : rel * nodes;
1440 float xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
1441 float values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values [i])/_bytecodes_parsed[i];
1442 if (cutoff <= rel) {
1443 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));
1444 abs_sum += abs;
1445 }
1446 }
1447 tty->print_cr("----------------------------------------------------------------------");
1448 float rel_sum = abs_sum * 100.0F / total;
1449 tty->print_cr("%10d %7.2f%% (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
1450 tty->print_cr("----------------------------------------------------------------------");
1451 tty->cr();
1452 }
1453 #endif
1454
1455 //----------------------------load_state_from----------------------------------
1456 // Load block/map/sp. But not do not touch iter/bci.
load_state_from(Block * block)1457 void Parse::load_state_from(Block* block) {
1458 set_block(block);
1459 // load the block's JVM state:
1460 set_map(block->start_map());
1461 set_sp( block->start_sp());
1462 }
1463
1464
1465 //-----------------------------record_state------------------------------------
record_state(Parse * p)1466 void Parse::Block::record_state(Parse* p) {
1467 assert(!is_merged(), "can only record state once, on 1st inflow");
1468 assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
1469 set_start_map(p->stop());
1470 }
1471
1472
1473 //------------------------------do_one_block-----------------------------------
do_one_block()1474 void Parse::do_one_block() {
1475 if (TraceOptoParse) {
1476 Block *b = block();
1477 int ns = b->num_successors();
1478 int nt = b->all_successors();
1479
1480 tty->print("Parsing block #%d at bci [%d,%d), successors: ",
1481 block()->rpo(), block()->start(), block()->limit());
1482 for (int i = 0; i < nt; i++) {
1483 tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
1484 }
1485 if (b->is_loop_head()) tty->print(" lphd");
1486 tty->cr();
1487 }
1488
1489 assert(block()->is_merged(), "must be merged before being parsed");
1490 block()->mark_parsed();
1491
1492 // Set iterator to start of block.
1493 iter().reset_to_bci(block()->start());
1494
1495 CompileLog* log = C->log();
1496
1497 // Parse bytecodes
1498 while (!stopped() && !failing()) {
1499 iter().next();
1500
1501 // Learn the current bci from the iterator:
1502 set_parse_bci(iter().cur_bci());
1503
1504 if (bci() == block()->limit()) {
1505 // Do not walk into the next block until directed by do_all_blocks.
1506 merge(bci());
1507 break;
1508 }
1509 assert(bci() < block()->limit(), "bci still in block");
1510
1511 if (log != NULL) {
1512 // Output an optional context marker, to help place actions
1513 // that occur during parsing of this BC. If there is no log
1514 // output until the next context string, this context string
1515 // will be silently ignored.
1516 log->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
1517 }
1518
1519 if (block()->has_trap_at(bci())) {
1520 // We must respect the flow pass's traps, because it will refuse
1521 // to produce successors for trapping blocks.
1522 int trap_index = block()->flow()->trap_index();
1523 assert(trap_index != 0, "trap index must be valid");
1524 uncommon_trap(trap_index);
1525 break;
1526 }
1527
1528 NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1529
1530 #ifdef ASSERT
1531 int pre_bc_sp = sp();
1532 int inputs, depth;
1533 bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1534 assert(!have_se || pre_bc_sp >= inputs, "have enough stack to execute this BC: pre_bc_sp=%d, inputs=%d", pre_bc_sp, inputs);
1535 #endif //ASSERT
1536
1537 do_one_bytecode();
1538
1539 assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
1540 "incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth);
1541
1542 do_exceptions();
1543
1544 NOT_PRODUCT( parse_histogram()->record_change(); );
1545
1546 if (log != NULL)
1547 log->clear_context(); // skip marker if nothing was printed
1548
1549 // Fall into next bytecode. Each bytecode normally has 1 sequential
1550 // successor which is typically made ready by visiting this bytecode.
1551 // If the successor has several predecessors, then it is a merge
1552 // point, starts a new basic block, and is handled like other basic blocks.
1553 }
1554 }
1555
1556
1557 //------------------------------merge------------------------------------------
set_parse_bci(int bci)1558 void Parse::set_parse_bci(int bci) {
1559 set_bci(bci);
1560 Node_Notes* nn = C->default_node_notes();
1561 if (nn == NULL) return;
1562
1563 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
1564 if (!DebugInlinedCalls && depth() > 1) {
1565 return;
1566 }
1567
1568 // Update the JVMS annotation, if present.
1569 JVMState* jvms = nn->jvms();
1570 if (jvms != NULL && jvms->bci() != bci) {
1571 // Update the JVMS.
1572 jvms = jvms->clone_shallow(C);
1573 jvms->set_bci(bci);
1574 nn->set_jvms(jvms);
1575 }
1576 }
1577
1578 //------------------------------merge------------------------------------------
1579 // Merge the current mapping into the basic block starting at bci
merge(int target_bci)1580 void Parse::merge(int target_bci) {
1581 Block* target = successor_for_bci(target_bci);
1582 if (target == NULL) { handle_missing_successor(target_bci); return; }
1583 assert(!target->is_ready(), "our arrival must be expected");
1584 int pnum = target->next_path_num();
1585 merge_common(target, pnum);
1586 }
1587
1588 //-------------------------merge_new_path--------------------------------------
1589 // Merge the current mapping into the basic block, using a new path
merge_new_path(int target_bci)1590 void Parse::merge_new_path(int target_bci) {
1591 Block* target = successor_for_bci(target_bci);
1592 if (target == NULL) { handle_missing_successor(target_bci); return; }
1593 assert(!target->is_ready(), "new path into frozen graph");
1594 int pnum = target->add_new_path();
1595 merge_common(target, pnum);
1596 }
1597
1598 //-------------------------merge_exception-------------------------------------
1599 // Merge the current mapping into the basic block starting at bci
1600 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
merge_exception(int target_bci)1601 void Parse::merge_exception(int target_bci) {
1602 assert(sp() == 1, "must have only the throw exception on the stack");
1603 Block* target = successor_for_bci(target_bci);
1604 if (target == NULL) { handle_missing_successor(target_bci); return; }
1605 assert(target->is_handler(), "exceptions are handled by special blocks");
1606 int pnum = target->add_new_path();
1607 merge_common(target, pnum);
1608 }
1609
1610 //--------------------handle_missing_successor---------------------------------
handle_missing_successor(int target_bci)1611 void Parse::handle_missing_successor(int target_bci) {
1612 #ifndef PRODUCT
1613 Block* b = block();
1614 int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1615 tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1616 #endif
1617 ShouldNotReachHere();
1618 }
1619
1620 //--------------------------merge_common---------------------------------------
merge_common(Parse::Block * target,int pnum)1621 void Parse::merge_common(Parse::Block* target, int pnum) {
1622 if (TraceOptoParse) {
1623 tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1624 }
1625
1626 // Zap extra stack slots to top
1627 assert(sp() == target->start_sp(), "");
1628 clean_stack(sp());
1629
1630 if (!target->is_merged()) { // No prior mapping at this bci
1631 if (TraceOptoParse) { tty->print(" with empty state"); }
1632
1633 // If this path is dead, do not bother capturing it as a merge.
1634 // It is "as if" we had 1 fewer predecessors from the beginning.
1635 if (stopped()) {
1636 if (TraceOptoParse) tty->print_cr(", but path is dead and doesn't count");
1637 return;
1638 }
1639
1640 // Make a region if we know there are multiple or unpredictable inputs.
1641 // (Also, if this is a plain fall-through, we might see another region,
1642 // which must not be allowed into this block's map.)
1643 if (pnum > PhiNode::Input // Known multiple inputs.
1644 || target->is_handler() // These have unpredictable inputs.
1645 || target->is_loop_head() // Known multiple inputs
1646 || control()->is_Region()) { // We must hide this guy.
1647
1648 int current_bci = bci();
1649 set_parse_bci(target->start()); // Set target bci
1650 if (target->is_SEL_head()) {
1651 DEBUG_ONLY( target->mark_merged_backedge(block()); )
1652 if (target->start() == 0) {
1653 // Add loop predicate for the special case when
1654 // there are backbranches to the method entry.
1655 add_empty_predicates();
1656 }
1657 }
1658 // Add a Region to start the new basic block. Phis will be added
1659 // later lazily.
1660 int edges = target->pred_count();
1661 if (edges < pnum) edges = pnum; // might be a new path!
1662 RegionNode *r = new RegionNode(edges+1);
1663 gvn().set_type(r, Type::CONTROL);
1664 record_for_igvn(r);
1665 // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1666 // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1667 r->init_req(pnum, control());
1668 set_control(r);
1669 set_parse_bci(current_bci); // Restore bci
1670 }
1671
1672 // Convert the existing Parser mapping into a mapping at this bci.
1673 store_state_to(target);
1674 assert(target->is_merged(), "do not come here twice");
1675
1676 } else { // Prior mapping at this bci
1677 if (TraceOptoParse) { tty->print(" with previous state"); }
1678 #ifdef ASSERT
1679 if (target->is_SEL_head()) {
1680 target->mark_merged_backedge(block());
1681 }
1682 #endif
1683 // We must not manufacture more phis if the target is already parsed.
1684 bool nophi = target->is_parsed();
1685
1686 SafePointNode* newin = map();// Hang on to incoming mapping
1687 Block* save_block = block(); // Hang on to incoming block;
1688 load_state_from(target); // Get prior mapping
1689
1690 assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1691 assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1692 assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1693 assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1694
1695 // Iterate over my current mapping and the old mapping.
1696 // Where different, insert Phi functions.
1697 // Use any existing Phi functions.
1698 assert(control()->is_Region(), "must be merging to a region");
1699 RegionNode* r = control()->as_Region();
1700
1701 // Compute where to merge into
1702 // Merge incoming control path
1703 r->init_req(pnum, newin->control());
1704
1705 if (pnum == 1) { // Last merge for this Region?
1706 if (!block()->flow()->is_irreducible_entry()) {
1707 Node* result = _gvn.transform_no_reclaim(r);
1708 if (r != result && TraceOptoParse) {
1709 tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1710 }
1711 }
1712 record_for_igvn(r);
1713 }
1714
1715 // Update all the non-control inputs to map:
1716 assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1717 bool check_elide_phi = target->is_SEL_backedge(save_block);
1718 for (uint j = 1; j < newin->req(); j++) {
1719 Node* m = map()->in(j); // Current state of target.
1720 Node* n = newin->in(j); // Incoming change to target state.
1721 PhiNode* phi;
1722 if (m->is_Phi() && m->as_Phi()->region() == r)
1723 phi = m->as_Phi();
1724 else
1725 phi = NULL;
1726 if (m != n) { // Different; must merge
1727 switch (j) {
1728 // Frame pointer and Return Address never changes
1729 case TypeFunc::FramePtr:// Drop m, use the original value
1730 case TypeFunc::ReturnAdr:
1731 break;
1732 case TypeFunc::Memory: // Merge inputs to the MergeMem node
1733 assert(phi == NULL, "the merge contains phis, not vice versa");
1734 merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1735 continue;
1736 default: // All normal stuff
1737 if (phi == NULL) {
1738 const JVMState* jvms = map()->jvms();
1739 if (EliminateNestedLocks &&
1740 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1741 // BoxLock nodes are not commoning.
1742 // Use old BoxLock node as merged box.
1743 assert(newin->jvms()->is_monitor_box(j), "sanity");
1744 // This assert also tests that nodes are BoxLock.
1745 assert(BoxLockNode::same_slot(n, m), "sanity");
1746 C->gvn_replace_by(n, m);
1747 } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1748 phi = ensure_phi(j, nophi);
1749 }
1750 }
1751 break;
1752 }
1753 }
1754 // At this point, n might be top if:
1755 // - there is no phi (because TypeFlow detected a conflict), or
1756 // - the corresponding control edges is top (a dead incoming path)
1757 // It is a bug if we create a phi which sees a garbage value on a live path.
1758
1759 if (phi != NULL) {
1760 assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1761 assert(phi->region() == r, "");
1762 phi->set_req(pnum, n); // Then add 'n' to the merge
1763 if (pnum == PhiNode::Input) {
1764 // Last merge for this Phi.
1765 // So far, Phis have had a reasonable type from ciTypeFlow.
1766 // Now _gvn will join that with the meet of current inputs.
1767 // BOTTOM is never permissible here, 'cause pessimistically
1768 // Phis of pointers cannot lose the basic pointer type.
1769 debug_only(const Type* bt1 = phi->bottom_type());
1770 assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1771 map()->set_req(j, _gvn.transform_no_reclaim(phi));
1772 debug_only(const Type* bt2 = phi->bottom_type());
1773 assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
1774 record_for_igvn(phi);
1775 }
1776 }
1777 } // End of for all values to be merged
1778
1779 if (pnum == PhiNode::Input &&
1780 !r->in(0)) { // The occasional useless Region
1781 assert(control() == r, "");
1782 set_control(r->nonnull_req());
1783 }
1784
1785 map()->merge_replaced_nodes_with(newin);
1786
1787 // newin has been subsumed into the lazy merge, and is now dead.
1788 set_block(save_block);
1789
1790 stop(); // done with this guy, for now
1791 }
1792
1793 if (TraceOptoParse) {
1794 tty->print_cr(" on path %d", pnum);
1795 }
1796
1797 // Done with this parser state.
1798 assert(stopped(), "");
1799 }
1800
1801
1802 //--------------------------merge_memory_edges---------------------------------
merge_memory_edges(MergeMemNode * n,int pnum,bool nophi)1803 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1804 // (nophi means we must not create phis, because we already parsed here)
1805 assert(n != NULL, "");
1806 // Merge the inputs to the MergeMems
1807 MergeMemNode* m = merged_memory();
1808
1809 assert(control()->is_Region(), "must be merging to a region");
1810 RegionNode* r = control()->as_Region();
1811
1812 PhiNode* base = NULL;
1813 MergeMemNode* remerge = NULL;
1814 for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1815 Node *p = mms.force_memory();
1816 Node *q = mms.memory2();
1817 if (mms.is_empty() && nophi) {
1818 // Trouble: No new splits allowed after a loop body is parsed.
1819 // Instead, wire the new split into a MergeMem on the backedge.
1820 // The optimizer will sort it out, slicing the phi.
1821 if (remerge == NULL) {
1822 guarantee(base != NULL, "");
1823 assert(base->in(0) != NULL, "should not be xformed away");
1824 remerge = MergeMemNode::make(base->in(pnum));
1825 gvn().set_type(remerge, Type::MEMORY);
1826 base->set_req(pnum, remerge);
1827 }
1828 remerge->set_memory_at(mms.alias_idx(), q);
1829 continue;
1830 }
1831 assert(!q->is_MergeMem(), "");
1832 PhiNode* phi;
1833 if (p != q) {
1834 phi = ensure_memory_phi(mms.alias_idx(), nophi);
1835 } else {
1836 if (p->is_Phi() && p->as_Phi()->region() == r)
1837 phi = p->as_Phi();
1838 else
1839 phi = NULL;
1840 }
1841 // Insert q into local phi
1842 if (phi != NULL) {
1843 assert(phi->region() == r, "");
1844 p = phi;
1845 phi->set_req(pnum, q);
1846 if (mms.at_base_memory()) {
1847 base = phi; // delay transforming it
1848 } else if (pnum == 1) {
1849 record_for_igvn(phi);
1850 p = _gvn.transform_no_reclaim(phi);
1851 }
1852 mms.set_memory(p);// store back through the iterator
1853 }
1854 }
1855 // Transform base last, in case we must fiddle with remerging.
1856 if (base != NULL && pnum == 1) {
1857 record_for_igvn(base);
1858 m->set_base_memory( _gvn.transform_no_reclaim(base) );
1859 }
1860 }
1861
1862
1863 //------------------------ensure_phis_everywhere-------------------------------
ensure_phis_everywhere()1864 void Parse::ensure_phis_everywhere() {
1865 ensure_phi(TypeFunc::I_O);
1866
1867 // Ensure a phi on all currently known memories.
1868 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
1869 ensure_memory_phi(mms.alias_idx());
1870 debug_only(mms.set_memory()); // keep the iterator happy
1871 }
1872
1873 // Note: This is our only chance to create phis for memory slices.
1874 // If we miss a slice that crops up later, it will have to be
1875 // merged into the base-memory phi that we are building here.
1876 // Later, the optimizer will comb out the knot, and build separate
1877 // phi-loops for each memory slice that matters.
1878
1879 // Monitors must nest nicely and not get confused amongst themselves.
1880 // Phi-ify everything up to the monitors, though.
1881 uint monoff = map()->jvms()->monoff();
1882 uint nof_monitors = map()->jvms()->nof_monitors();
1883
1884 assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
1885 bool check_elide_phi = block()->is_SEL_head();
1886 for (uint i = TypeFunc::Parms; i < monoff; i++) {
1887 if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
1888 ensure_phi(i);
1889 }
1890 }
1891
1892 // Even monitors need Phis, though they are well-structured.
1893 // This is true for OSR methods, and also for the rare cases where
1894 // a monitor object is the subject of a replace_in_map operation.
1895 // See bugs 4426707 and 5043395.
1896 for (uint m = 0; m < nof_monitors; m++) {
1897 ensure_phi(map()->jvms()->monitor_obj_offset(m));
1898 }
1899 }
1900
1901
1902 //-----------------------------add_new_path------------------------------------
1903 // Add a previously unaccounted predecessor to this block.
add_new_path()1904 int Parse::Block::add_new_path() {
1905 // If there is no map, return the lowest unused path number.
1906 if (!is_merged()) return pred_count()+1; // there will be a map shortly
1907
1908 SafePointNode* map = start_map();
1909 if (!map->control()->is_Region())
1910 return pred_count()+1; // there may be a region some day
1911 RegionNode* r = map->control()->as_Region();
1912
1913 // Add new path to the region.
1914 uint pnum = r->req();
1915 r->add_req(NULL);
1916
1917 for (uint i = 1; i < map->req(); i++) {
1918 Node* n = map->in(i);
1919 if (i == TypeFunc::Memory) {
1920 // Ensure a phi on all currently known memories.
1921 for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1922 Node* phi = mms.memory();
1923 if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1924 assert(phi->req() == pnum, "must be same size as region");
1925 phi->add_req(NULL);
1926 }
1927 }
1928 } else {
1929 if (n->is_Phi() && n->as_Phi()->region() == r) {
1930 assert(n->req() == pnum, "must be same size as region");
1931 n->add_req(NULL);
1932 }
1933 }
1934 }
1935
1936 return pnum;
1937 }
1938
1939 //------------------------------ensure_phi-------------------------------------
1940 // Turn the idx'th entry of the current map into a Phi
ensure_phi(int idx,bool nocreate)1941 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
1942 SafePointNode* map = this->map();
1943 Node* region = map->control();
1944 assert(region->is_Region(), "");
1945
1946 Node* o = map->in(idx);
1947 assert(o != NULL, "");
1948
1949 if (o == top()) return NULL; // TOP always merges into TOP
1950
1951 if (o->is_Phi() && o->as_Phi()->region() == region) {
1952 return o->as_Phi();
1953 }
1954
1955 // Now use a Phi here for merging
1956 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1957 const JVMState* jvms = map->jvms();
1958 const Type* t = NULL;
1959 if (jvms->is_loc(idx)) {
1960 t = block()->local_type_at(idx - jvms->locoff());
1961 } else if (jvms->is_stk(idx)) {
1962 t = block()->stack_type_at(idx - jvms->stkoff());
1963 } else if (jvms->is_mon(idx)) {
1964 assert(!jvms->is_monitor_box(idx), "no phis for boxes");
1965 t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
1966 } else if ((uint)idx < TypeFunc::Parms) {
1967 t = o->bottom_type(); // Type::RETURN_ADDRESS or such-like.
1968 } else {
1969 assert(false, "no type information for this phi");
1970 }
1971
1972 // If the type falls to bottom, then this must be a local that
1973 // is mixing ints and oops or some such. Forcing it to top
1974 // makes it go dead.
1975 if (t == Type::BOTTOM) {
1976 map->set_req(idx, top());
1977 return NULL;
1978 }
1979
1980 // Do not create phis for top either.
1981 // A top on a non-null control flow must be an unused even after the.phi.
1982 if (t == Type::TOP || t == Type::HALF) {
1983 map->set_req(idx, top());
1984 return NULL;
1985 }
1986
1987 PhiNode* phi = PhiNode::make(region, o, t);
1988 gvn().set_type(phi, t);
1989 if (C->do_escape_analysis()) record_for_igvn(phi);
1990 map->set_req(idx, phi);
1991 return phi;
1992 }
1993
1994 //--------------------------ensure_memory_phi----------------------------------
1995 // Turn the idx'th slice of the current memory into a Phi
ensure_memory_phi(int idx,bool nocreate)1996 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
1997 MergeMemNode* mem = merged_memory();
1998 Node* region = control();
1999 assert(region->is_Region(), "");
2000
2001 Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
2002 assert(o != NULL && o != top(), "");
2003
2004 PhiNode* phi;
2005 if (o->is_Phi() && o->as_Phi()->region() == region) {
2006 phi = o->as_Phi();
2007 if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
2008 // clone the shared base memory phi to make a new memory split
2009 assert(!nocreate, "Cannot build a phi for a block already parsed.");
2010 const Type* t = phi->bottom_type();
2011 const TypePtr* adr_type = C->get_adr_type(idx);
2012 phi = phi->slice_memory(adr_type);
2013 gvn().set_type(phi, t);
2014 }
2015 return phi;
2016 }
2017
2018 // Now use a Phi here for merging
2019 assert(!nocreate, "Cannot build a phi for a block already parsed.");
2020 const Type* t = o->bottom_type();
2021 const TypePtr* adr_type = C->get_adr_type(idx);
2022 phi = PhiNode::make(region, o, t, adr_type);
2023 gvn().set_type(phi, t);
2024 if (idx == Compile::AliasIdxBot)
2025 mem->set_base_memory(phi);
2026 else
2027 mem->set_memory_at(idx, phi);
2028 return phi;
2029 }
2030
2031 //------------------------------call_register_finalizer-----------------------
2032 // Check the klass of the receiver and call register_finalizer if the
2033 // class need finalization.
call_register_finalizer()2034 void Parse::call_register_finalizer() {
2035 Node* receiver = local(0);
2036 assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
2037 "must have non-null instance type");
2038
2039 const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
2040 if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
2041 // The type isn't known exactly so see if CHA tells us anything.
2042 ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
2043 if (!Dependencies::has_finalizable_subclass(ik)) {
2044 // No finalizable subclasses so skip the dynamic check.
2045 C->dependencies()->assert_has_no_finalizable_subclasses(ik);
2046 return;
2047 }
2048 }
2049
2050 // Insert a dynamic test for whether the instance needs
2051 // finalization. In general this will fold up since the concrete
2052 // class is often visible so the access flags are constant.
2053 Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
2054 Node* klass = _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), klass_addr, TypeInstPtr::KLASS));
2055
2056 Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
2057 Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT, MemNode::unordered);
2058
2059 Node* mask = _gvn.transform(new AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
2060 Node* check = _gvn.transform(new CmpINode(mask, intcon(0)));
2061 Node* test = _gvn.transform(new BoolNode(check, BoolTest::ne));
2062
2063 IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
2064
2065 RegionNode* result_rgn = new RegionNode(3);
2066 record_for_igvn(result_rgn);
2067
2068 Node *skip_register = _gvn.transform(new IfFalseNode(iff));
2069 result_rgn->init_req(1, skip_register);
2070
2071 Node *needs_register = _gvn.transform(new IfTrueNode(iff));
2072 set_control(needs_register);
2073 if (stopped()) {
2074 // There is no slow path.
2075 result_rgn->init_req(2, top());
2076 } else {
2077 Node *call = make_runtime_call(RC_NO_LEAF,
2078 OptoRuntime::register_finalizer_Type(),
2079 OptoRuntime::register_finalizer_Java(),
2080 NULL, TypePtr::BOTTOM,
2081 receiver);
2082 make_slow_call_ex(call, env()->Throwable_klass(), true);
2083
2084 Node* fast_io = call->in(TypeFunc::I_O);
2085 Node* fast_mem = call->in(TypeFunc::Memory);
2086 // These two phis are pre-filled with copies of of the fast IO and Memory
2087 Node* io_phi = PhiNode::make(result_rgn, fast_io, Type::ABIO);
2088 Node* mem_phi = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
2089
2090 result_rgn->init_req(2, control());
2091 io_phi ->init_req(2, i_o());
2092 mem_phi ->init_req(2, reset_memory());
2093
2094 set_all_memory( _gvn.transform(mem_phi) );
2095 set_i_o( _gvn.transform(io_phi) );
2096 }
2097
2098 set_control( _gvn.transform(result_rgn) );
2099 }
2100
2101 // Add check to deoptimize once holder klass is fully initialized.
clinit_deopt()2102 void Parse::clinit_deopt() {
2103 assert(C->has_method(), "only for normal compilations");
2104 assert(depth() == 1, "only for main compiled method");
2105 assert(is_normal_parse(), "no barrier needed on osr entry");
2106 assert(!method()->holder()->is_not_initialized(), "initialization should have been started");
2107
2108 set_parse_bci(0);
2109
2110 Node* holder = makecon(TypeKlassPtr::make(method()->holder()));
2111 guard_klass_being_initialized(holder);
2112 }
2113
2114 // Add check to deoptimize if RTM state is not ProfileRTM
rtm_deopt()2115 void Parse::rtm_deopt() {
2116 #if INCLUDE_RTM_OPT
2117 if (C->profile_rtm()) {
2118 assert(C->has_method(), "only for normal compilations");
2119 assert(!C->method()->method_data()->is_empty(), "MDO is needed to record RTM state");
2120 assert(depth() == 1, "generate check only for main compiled method");
2121
2122 // Set starting bci for uncommon trap.
2123 set_parse_bci(is_osr_parse() ? osr_bci() : 0);
2124
2125 // Load the rtm_state from the MethodData.
2126 const TypePtr* adr_type = TypeMetadataPtr::make(C->method()->method_data());
2127 Node* mdo = makecon(adr_type);
2128 int offset = MethodData::rtm_state_offset_in_bytes();
2129 Node* adr_node = basic_plus_adr(mdo, mdo, offset);
2130 Node* rtm_state = make_load(control(), adr_node, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2131
2132 // Separate Load from Cmp by Opaque.
2133 // In expand_macro_nodes() it will be replaced either
2134 // with this load when there are locks in the code
2135 // or with ProfileRTM (cmp->in(2)) otherwise so that
2136 // the check will fold.
2137 Node* profile_state = makecon(TypeInt::make(ProfileRTM));
2138 Node* opq = _gvn.transform( new Opaque3Node(C, rtm_state, Opaque3Node::RTM_OPT) );
2139 Node* chk = _gvn.transform( new CmpINode(opq, profile_state) );
2140 Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
2141 // Branch to failure if state was changed
2142 { BuildCutout unless(this, tst, PROB_ALWAYS);
2143 uncommon_trap(Deoptimization::Reason_rtm_state_change,
2144 Deoptimization::Action_make_not_entrant);
2145 }
2146 }
2147 #endif
2148 }
2149
decrement_age()2150 void Parse::decrement_age() {
2151 MethodCounters* mc = method()->ensure_method_counters();
2152 if (mc == NULL) {
2153 C->record_failure("Must have MCs");
2154 return;
2155 }
2156 assert(!is_osr_parse(), "Not doing this for OSRs");
2157
2158 // Set starting bci for uncommon trap.
2159 set_parse_bci(0);
2160
2161 const TypePtr* adr_type = TypeRawPtr::make((address)mc);
2162 Node* mc_adr = makecon(adr_type);
2163 Node* cnt_adr = basic_plus_adr(mc_adr, mc_adr, in_bytes(MethodCounters::nmethod_age_offset()));
2164 Node* cnt = make_load(control(), cnt_adr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2165 Node* decr = _gvn.transform(new SubINode(cnt, makecon(TypeInt::ONE)));
2166 store_to_memory(control(), cnt_adr, decr, T_INT, adr_type, MemNode::unordered);
2167 Node *chk = _gvn.transform(new CmpINode(decr, makecon(TypeInt::ZERO)));
2168 Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::gt));
2169 { BuildCutout unless(this, tst, PROB_ALWAYS);
2170 uncommon_trap(Deoptimization::Reason_tenured,
2171 Deoptimization::Action_make_not_entrant);
2172 }
2173 }
2174
2175 //------------------------------return_current---------------------------------
2176 // Append current _map to _exit_return
return_current(Node * value)2177 void Parse::return_current(Node* value) {
2178 if (RegisterFinalizersAtInit &&
2179 method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2180 call_register_finalizer();
2181 }
2182
2183 // Do not set_parse_bci, so that return goo is credited to the return insn.
2184 set_bci(InvocationEntryBci);
2185 if (method()->is_synchronized() && GenerateSynchronizationCode) {
2186 shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2187 }
2188 if (C->env()->dtrace_method_probes()) {
2189 make_dtrace_method_exit(method());
2190 }
2191 SafePointNode* exit_return = _exits.map();
2192 exit_return->in( TypeFunc::Control )->add_req( control() );
2193 exit_return->in( TypeFunc::I_O )->add_req( i_o () );
2194 Node *mem = exit_return->in( TypeFunc::Memory );
2195 for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2196 if (mms.is_empty()) {
2197 // get a copy of the base memory, and patch just this one input
2198 const TypePtr* adr_type = mms.adr_type(C);
2199 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2200 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2201 gvn().set_type_bottom(phi);
2202 phi->del_req(phi->req()-1); // prepare to re-patch
2203 mms.set_memory(phi);
2204 }
2205 mms.memory()->add_req(mms.memory2());
2206 }
2207
2208 // frame pointer is always same, already captured
2209 if (value != NULL) {
2210 // If returning oops to an interface-return, there is a silent free
2211 // cast from oop to interface allowed by the Verifier. Make it explicit
2212 // here.
2213 Node* phi = _exits.argument(0);
2214 const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
2215 if (tr && tr->klass()->is_loaded() &&
2216 tr->klass()->is_interface()) {
2217 const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
2218 if (tp && tp->klass()->is_loaded() &&
2219 !tp->klass()->is_interface()) {
2220 // sharpen the type eagerly; this eases certain assert checking
2221 if (tp->higher_equal(TypeInstPtr::NOTNULL))
2222 tr = tr->join_speculative(TypeInstPtr::NOTNULL)->is_instptr();
2223 value = _gvn.transform(new CheckCastPPNode(0, value, tr));
2224 }
2225 } else {
2226 // Also handle returns of oop-arrays to an arrays-of-interface return
2227 const TypeInstPtr* phi_tip;
2228 const TypeInstPtr* val_tip;
2229 Type::get_arrays_base_elements(phi->bottom_type(), value->bottom_type(), &phi_tip, &val_tip);
2230 if (phi_tip != NULL && phi_tip->is_loaded() && phi_tip->klass()->is_interface() &&
2231 val_tip != NULL && val_tip->is_loaded() && !val_tip->klass()->is_interface()) {
2232 value = _gvn.transform(new CheckCastPPNode(0, value, phi->bottom_type()));
2233 }
2234 }
2235 phi->add_req(value);
2236 }
2237
2238 if (_first_return) {
2239 _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
2240 _first_return = false;
2241 } else {
2242 _exits.map()->merge_replaced_nodes_with(map());
2243 }
2244
2245 stop_and_kill_map(); // This CFG path dies here
2246 }
2247
2248
2249 //------------------------------add_safepoint----------------------------------
add_safepoint()2250 void Parse::add_safepoint() {
2251 // See if we can avoid this safepoint. No need for a SafePoint immediately
2252 // after a Call (except Leaf Call) or another SafePoint.
2253 Node *proj = control();
2254 uint parms = TypeFunc::Parms+1;
2255 if( proj->is_Proj() ) {
2256 Node *n0 = proj->in(0);
2257 if( n0->is_Catch() ) {
2258 n0 = n0->in(0)->in(0);
2259 assert( n0->is_Call(), "expect a call here" );
2260 }
2261 if( n0->is_Call() ) {
2262 if( n0->as_Call()->guaranteed_safepoint() )
2263 return;
2264 } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2265 return;
2266 }
2267 }
2268
2269 // Clear out dead values from the debug info.
2270 kill_dead_locals();
2271
2272 // Clone the JVM State
2273 SafePointNode *sfpnt = new SafePointNode(parms, NULL);
2274
2275 // Capture memory state BEFORE a SafePoint. Since we can block at a
2276 // SafePoint we need our GC state to be safe; i.e. we need all our current
2277 // write barriers (card marks) to not float down after the SafePoint so we
2278 // must read raw memory. Likewise we need all oop stores to match the card
2279 // marks. If deopt can happen, we need ALL stores (we need the correct JVM
2280 // state on a deopt).
2281
2282 // We do not need to WRITE the memory state after a SafePoint. The control
2283 // edge will keep card-marks and oop-stores from floating up from below a
2284 // SafePoint and our true dependency added here will keep them from floating
2285 // down below a SafePoint.
2286
2287 // Clone the current memory state
2288 Node* mem = MergeMemNode::make(map()->memory());
2289
2290 mem = _gvn.transform(mem);
2291
2292 // Pass control through the safepoint
2293 sfpnt->init_req(TypeFunc::Control , control());
2294 // Fix edges normally used by a call
2295 sfpnt->init_req(TypeFunc::I_O , top() );
2296 sfpnt->init_req(TypeFunc::Memory , mem );
2297 sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2298 sfpnt->init_req(TypeFunc::FramePtr , top() );
2299
2300 // Create a node for the polling address
2301 Node *polladr;
2302 Node *thread = _gvn.transform(new ThreadLocalNode());
2303 Node *polling_page_load_addr = _gvn.transform(basic_plus_adr(top(), thread, in_bytes(Thread::polling_page_offset())));
2304 polladr = make_load(control(), polling_page_load_addr, TypeRawPtr::BOTTOM, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
2305 sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2306
2307 // Fix up the JVM State edges
2308 add_safepoint_edges(sfpnt);
2309 Node *transformed_sfpnt = _gvn.transform(sfpnt);
2310 set_control(transformed_sfpnt);
2311
2312 // Provide an edge from root to safepoint. This makes the safepoint
2313 // appear useful until the parse has completed.
2314 if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2315 assert(C->root() != NULL, "Expect parse is still valid");
2316 C->root()->add_prec(transformed_sfpnt);
2317 }
2318 }
2319
2320 #ifndef PRODUCT
2321 //------------------------show_parse_info--------------------------------------
show_parse_info()2322 void Parse::show_parse_info() {
2323 InlineTree* ilt = NULL;
2324 if (C->ilt() != NULL) {
2325 JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2326 ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2327 }
2328 if (PrintCompilation && Verbose) {
2329 if (depth() == 1) {
2330 if( ilt->count_inlines() ) {
2331 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2332 ilt->count_inline_bcs());
2333 tty->cr();
2334 }
2335 } else {
2336 if (method()->is_synchronized()) tty->print("s");
2337 if (method()->has_exception_handlers()) tty->print("!");
2338 // Check this is not the final compiled version
2339 if (C->trap_can_recompile()) {
2340 tty->print("-");
2341 } else {
2342 tty->print(" ");
2343 }
2344 method()->print_short_name();
2345 if (is_osr_parse()) {
2346 tty->print(" @ %d", osr_bci());
2347 }
2348 tty->print(" (%d bytes)",method()->code_size());
2349 if (ilt->count_inlines()) {
2350 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2351 ilt->count_inline_bcs());
2352 }
2353 tty->cr();
2354 }
2355 }
2356 if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2357 // Print that we succeeded; suppress this message on the first osr parse.
2358
2359 if (method()->is_synchronized()) tty->print("s");
2360 if (method()->has_exception_handlers()) tty->print("!");
2361 // Check this is not the final compiled version
2362 if (C->trap_can_recompile() && depth() == 1) {
2363 tty->print("-");
2364 } else {
2365 tty->print(" ");
2366 }
2367 if( depth() != 1 ) { tty->print(" "); } // missing compile count
2368 for (int i = 1; i < depth(); ++i) { tty->print(" "); }
2369 method()->print_short_name();
2370 if (is_osr_parse()) {
2371 tty->print(" @ %d", osr_bci());
2372 }
2373 if (ilt->caller_bci() != -1) {
2374 tty->print(" @ %d", ilt->caller_bci());
2375 }
2376 tty->print(" (%d bytes)",method()->code_size());
2377 if (ilt->count_inlines()) {
2378 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2379 ilt->count_inline_bcs());
2380 }
2381 tty->cr();
2382 }
2383 }
2384
2385
2386 //------------------------------dump-------------------------------------------
2387 // Dump information associated with the bytecodes of current _method
dump()2388 void Parse::dump() {
2389 if( method() != NULL ) {
2390 // Iterate over bytecodes
2391 ciBytecodeStream iter(method());
2392 for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2393 dump_bci( iter.cur_bci() );
2394 tty->cr();
2395 }
2396 }
2397 }
2398
2399 // Dump information associated with a byte code index, 'bci'
dump_bci(int bci)2400 void Parse::dump_bci(int bci) {
2401 // Output info on merge-points, cloning, and within _jsr..._ret
2402 // NYI
2403 tty->print(" bci:%d", bci);
2404 }
2405
2406 #endif
2407