Fri, 16 Oct 2009 02:05:46 -0700
6888898: CMS: ReduceInitialCardMarks unsafe in the presence of cms precleaning
6889757: G1: enable card mark elision for initializing writes from compiled code (ReduceInitialCardMarks)
Summary: Defer the (compiler-elided) card-mark upon a slow-path allocation until after the store and before the next subsequent safepoint; G1 now answers yes to can_elide_tlab_write_barriers().
Reviewed-by: jcoomes, kvn, never
1 /*
2 * Copyright 1997-2009 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 #include "incls/_precompiled.incl"
26 #include "incls/_parse1.cpp.incl"
28 // Static array so we can figure out which bytecodes stop us from compiling
29 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
30 // and eventually should be encapsulated in a proper class (gri 8/18/98).
32 int nodes_created = 0;
33 int methods_parsed = 0;
34 int methods_seen = 0;
35 int blocks_parsed = 0;
36 int blocks_seen = 0;
38 int explicit_null_checks_inserted = 0;
39 int explicit_null_checks_elided = 0;
40 int all_null_checks_found = 0, implicit_null_checks = 0;
41 int implicit_null_throws = 0;
43 int reclaim_idx = 0;
44 int reclaim_in = 0;
45 int reclaim_node = 0;
47 #ifndef PRODUCT
48 bool Parse::BytecodeParseHistogram::_initialized = false;
49 uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
50 uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
51 uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
52 uint Parse::BytecodeParseHistogram::_new_values [Bytecodes::number_of_codes];
53 #endif
55 //------------------------------print_statistics-------------------------------
56 #ifndef PRODUCT
57 void Parse::print_statistics() {
58 tty->print_cr("--- Compiler Statistics ---");
59 tty->print("Methods seen: %d Methods parsed: %d", methods_seen, methods_parsed);
60 tty->print(" Nodes created: %d", nodes_created);
61 tty->cr();
62 if (methods_seen != methods_parsed)
63 tty->print_cr("Reasons for parse failures (NOT cumulative):");
64 tty->print_cr("Blocks parsed: %d Blocks seen: %d", blocks_parsed, blocks_seen);
66 if( explicit_null_checks_inserted )
67 tty->print_cr("%d original NULL checks - %d elided (%2d%%); optimizer leaves %d,", explicit_null_checks_inserted, explicit_null_checks_elided, (100*explicit_null_checks_elided)/explicit_null_checks_inserted, all_null_checks_found);
68 if( all_null_checks_found )
69 tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
70 (100*implicit_null_checks)/all_null_checks_found);
71 if( implicit_null_throws )
72 tty->print_cr("%d implicit null exceptions at runtime",
73 implicit_null_throws);
75 if( PrintParseStatistics && BytecodeParseHistogram::initialized() ) {
76 BytecodeParseHistogram::print();
77 }
78 }
79 #endif
81 //------------------------------ON STACK REPLACEMENT---------------------------
83 // Construct a node which can be used to get incoming state for
84 // on stack replacement.
85 Node *Parse::fetch_interpreter_state(int index,
86 BasicType bt,
87 Node *local_addrs,
88 Node *local_addrs_base) {
89 Node *mem = memory(Compile::AliasIdxRaw);
90 Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
92 // Very similar to LoadNode::make, except we handle un-aligned longs and
93 // doubles on Sparc. Intel can handle them just fine directly.
94 Node *l;
95 switch( bt ) { // Signature is flattened
96 case T_INT: l = new (C, 3) LoadINode( 0, mem, adr, TypeRawPtr::BOTTOM ); break;
97 case T_FLOAT: l = new (C, 3) LoadFNode( 0, mem, adr, TypeRawPtr::BOTTOM ); break;
98 case T_ADDRESS: l = new (C, 3) LoadPNode( 0, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM ); break;
99 case T_OBJECT: l = new (C, 3) LoadPNode( 0, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM ); break;
100 case T_LONG:
101 case T_DOUBLE: {
102 // Since arguments are in reverse order, the argument address 'adr'
103 // refers to the back half of the long/double. Recompute adr.
104 adr = basic_plus_adr( local_addrs_base, local_addrs, -(index+1)*wordSize );
105 if( Matcher::misaligned_doubles_ok ) {
106 l = (bt == T_DOUBLE)
107 ? (Node*)new (C, 3) LoadDNode( 0, mem, adr, TypeRawPtr::BOTTOM )
108 : (Node*)new (C, 3) LoadLNode( 0, mem, adr, TypeRawPtr::BOTTOM );
109 } else {
110 l = (bt == T_DOUBLE)
111 ? (Node*)new (C, 3) LoadD_unalignedNode( 0, mem, adr, TypeRawPtr::BOTTOM )
112 : (Node*)new (C, 3) LoadL_unalignedNode( 0, mem, adr, TypeRawPtr::BOTTOM );
113 }
114 break;
115 }
116 default: ShouldNotReachHere();
117 }
118 return _gvn.transform(l);
119 }
121 // Helper routine to prevent the interpreter from handing
122 // unexpected typestate to an OSR method.
123 // The Node l is a value newly dug out of the interpreter frame.
124 // The type is the type predicted by ciTypeFlow. Note that it is
125 // not a general type, but can only come from Type::get_typeflow_type.
126 // The safepoint is a map which will feed an uncommon trap.
127 Node* Parse::check_interpreter_type(Node* l, const Type* type,
128 SafePointNode* &bad_type_exit) {
130 const TypeOopPtr* tp = type->isa_oopptr();
132 // TypeFlow may assert null-ness if a type appears unloaded.
133 if (type == TypePtr::NULL_PTR ||
134 (tp != NULL && !tp->klass()->is_loaded())) {
135 // Value must be null, not a real oop.
136 Node* chk = _gvn.transform( new (C, 3) CmpPNode(l, null()) );
137 Node* tst = _gvn.transform( new (C, 2) BoolNode(chk, BoolTest::eq) );
138 IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
139 set_control(_gvn.transform( new (C, 1) IfTrueNode(iff) ));
140 Node* bad_type = _gvn.transform( new (C, 1) IfFalseNode(iff) );
141 bad_type_exit->control()->add_req(bad_type);
142 l = null();
143 }
145 // Typeflow can also cut off paths from the CFG, based on
146 // types which appear unloaded, or call sites which appear unlinked.
147 // When paths are cut off, values at later merge points can rise
148 // toward more specific classes. Make sure these specific classes
149 // are still in effect.
150 if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
151 // TypeFlow asserted a specific object type. Value must have that type.
152 Node* bad_type_ctrl = NULL;
153 l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
154 bad_type_exit->control()->add_req(bad_type_ctrl);
155 }
157 BasicType bt_l = _gvn.type(l)->basic_type();
158 BasicType bt_t = type->basic_type();
159 assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
160 return l;
161 }
163 // Helper routine which sets up elements of the initial parser map when
164 // performing a parse for on stack replacement. Add values into map.
165 // The only parameter contains the address of a interpreter arguments.
166 void Parse::load_interpreter_state(Node* osr_buf) {
167 int index;
168 int max_locals = jvms()->loc_size();
169 int max_stack = jvms()->stk_size();
172 // Mismatch between method and jvms can occur since map briefly held
173 // an OSR entry state (which takes up one RawPtr word).
174 assert(max_locals == method()->max_locals(), "sanity");
175 assert(max_stack >= method()->max_stack(), "sanity");
176 assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
177 assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
179 // Find the start block.
180 Block* osr_block = start_block();
181 assert(osr_block->start() == osr_bci(), "sanity");
183 // Set initial BCI.
184 set_parse_bci(osr_block->start());
186 // Set initial stack depth.
187 set_sp(osr_block->start_sp());
189 // Check bailouts. We currently do not perform on stack replacement
190 // of loops in catch blocks or loops which branch with a non-empty stack.
191 if (sp() != 0) {
192 C->record_method_not_compilable("OSR starts with non-empty stack");
193 return;
194 }
195 // Do not OSR inside finally clauses:
196 if (osr_block->has_trap_at(osr_block->start())) {
197 C->record_method_not_compilable("OSR starts with an immediate trap");
198 return;
199 }
201 // Commute monitors from interpreter frame to compiler frame.
202 assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
203 int mcnt = osr_block->flow()->monitor_count();
204 Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
205 for (index = 0; index < mcnt; index++) {
206 // Make a BoxLockNode for the monitor.
207 Node *box = _gvn.transform(new (C, 1) BoxLockNode(next_monitor()));
210 // Displaced headers and locked objects are interleaved in the
211 // temp OSR buffer. We only copy the locked objects out here.
212 // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
213 Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
214 // Try and copy the displaced header to the BoxNode
215 Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);
218 store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw);
220 // Build a bogus FastLockNode (no code will be generated) and push the
221 // monitor into our debug info.
222 const FastLockNode *flock = _gvn.transform(new (C, 3) FastLockNode( 0, lock_object, box ))->as_FastLock();
223 map()->push_monitor(flock);
225 // If the lock is our method synchronization lock, tuck it away in
226 // _sync_lock for return and rethrow exit paths.
227 if (index == 0 && method()->is_synchronized()) {
228 _synch_lock = flock;
229 }
230 }
232 // Use the raw liveness computation to make sure that unexpected
233 // values don't propagate into the OSR frame.
234 MethodLivenessResult live_locals = method()->raw_liveness_at_bci(osr_bci());
235 if (!live_locals.is_valid()) {
236 // Degenerate or breakpointed method.
237 C->record_method_not_compilable("OSR in empty or breakpointed method");
238 return;
239 }
241 // Extract the needed locals from the interpreter frame.
242 Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);
244 // find all the locals that the interpreter thinks contain live oops
245 const BitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
246 for (index = 0; index < max_locals; index++) {
248 if (!live_locals.at(index)) {
249 continue;
250 }
252 const Type *type = osr_block->local_type_at(index);
254 if (type->isa_oopptr() != NULL) {
256 // 6403625: Verify that the interpreter oopMap thinks that the oop is live
257 // else we might load a stale oop if the MethodLiveness disagrees with the
258 // result of the interpreter. If the interpreter says it is dead we agree
259 // by making the value go to top.
260 //
262 if (!live_oops.at(index)) {
263 if (C->log() != NULL) {
264 C->log()->elem("OSR_mismatch local_index='%d'",index);
265 }
266 set_local(index, null());
267 // and ignore it for the loads
268 continue;
269 }
270 }
272 // Filter out TOP, HALF, and BOTTOM. (Cf. ensure_phi.)
273 if (type == Type::TOP || type == Type::HALF) {
274 continue;
275 }
276 // If the type falls to bottom, then this must be a local that
277 // is mixing ints and oops or some such. Forcing it to top
278 // makes it go dead.
279 if (type == Type::BOTTOM) {
280 continue;
281 }
282 // Construct code to access the appropriate local.
283 Node *value = fetch_interpreter_state(index, type->basic_type(), locals_addr, osr_buf);
284 set_local(index, value);
285 }
287 // Extract the needed stack entries from the interpreter frame.
288 for (index = 0; index < sp(); index++) {
289 const Type *type = osr_block->stack_type_at(index);
290 if (type != Type::TOP) {
291 // Currently the compiler bails out when attempting to on stack replace
292 // at a bci with a non-empty stack. We should not reach here.
293 ShouldNotReachHere();
294 }
295 }
297 // End the OSR migration
298 make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
299 CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
300 "OSR_migration_end", TypeRawPtr::BOTTOM,
301 osr_buf);
303 // Now that the interpreter state is loaded, make sure it will match
304 // at execution time what the compiler is expecting now:
305 SafePointNode* bad_type_exit = clone_map();
306 bad_type_exit->set_control(new (C, 1) RegionNode(1));
308 for (index = 0; index < max_locals; index++) {
309 if (stopped()) break;
310 Node* l = local(index);
311 if (l->is_top()) continue; // nothing here
312 const Type *type = osr_block->local_type_at(index);
313 if (type->isa_oopptr() != NULL) {
314 if (!live_oops.at(index)) {
315 // skip type check for dead oops
316 continue;
317 }
318 }
319 set_local(index, check_interpreter_type(l, type, bad_type_exit));
320 }
322 for (index = 0; index < sp(); index++) {
323 if (stopped()) break;
324 Node* l = stack(index);
325 if (l->is_top()) continue; // nothing here
326 const Type *type = osr_block->stack_type_at(index);
327 set_stack(index, check_interpreter_type(l, type, bad_type_exit));
328 }
330 if (bad_type_exit->control()->req() > 1) {
331 // Build an uncommon trap here, if any inputs can be unexpected.
332 bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
333 record_for_igvn(bad_type_exit->control());
334 SafePointNode* types_are_good = map();
335 set_map(bad_type_exit);
336 // The unexpected type happens because a new edge is active
337 // in the CFG, which typeflow had previously ignored.
338 // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
339 // This x will be typed as Integer if notReached is not yet linked.
340 uncommon_trap(Deoptimization::Reason_unreached,
341 Deoptimization::Action_reinterpret);
342 set_map(types_are_good);
343 }
344 }
346 //------------------------------Parse------------------------------------------
347 // Main parser constructor.
348 Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses)
349 : _exits(caller)
350 {
351 // Init some variables
352 _caller = caller;
353 _method = parse_method;
354 _expected_uses = expected_uses;
355 _depth = 1 + (caller->has_method() ? caller->depth() : 0);
356 _wrote_final = false;
357 _entry_bci = InvocationEntryBci;
358 _tf = NULL;
359 _block = NULL;
360 debug_only(_block_count = -1);
361 debug_only(_blocks = (Block*)-1);
362 #ifndef PRODUCT
363 if (PrintCompilation || PrintOpto) {
364 // Make sure I have an inline tree, so I can print messages about it.
365 JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
366 InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method, true);
367 }
368 _max_switch_depth = 0;
369 _est_switch_depth = 0;
370 #endif
372 _tf = TypeFunc::make(method());
373 _iter.reset_to_method(method());
374 _flow = method()->get_flow_analysis();
375 if (_flow->failing()) {
376 C->record_method_not_compilable_all_tiers(_flow->failure_reason());
377 }
379 #ifndef PRODUCT
380 if (_flow->has_irreducible_entry()) {
381 C->set_parsed_irreducible_loop(true);
382 }
383 #endif
385 if (_expected_uses <= 0) {
386 _prof_factor = 1;
387 } else {
388 float prof_total = parse_method->interpreter_invocation_count();
389 if (prof_total <= _expected_uses) {
390 _prof_factor = 1;
391 } else {
392 _prof_factor = _expected_uses / prof_total;
393 }
394 }
396 CompileLog* log = C->log();
397 if (log != NULL) {
398 log->begin_head("parse method='%d' uses='%g'",
399 log->identify(parse_method), expected_uses);
400 if (depth() == 1 && C->is_osr_compilation()) {
401 log->print(" osr_bci='%d'", C->entry_bci());
402 }
403 log->stamp();
404 log->end_head();
405 }
407 // Accumulate deoptimization counts.
408 // (The range_check and store_check counts are checked elsewhere.)
409 ciMethodData* md = method()->method_data();
410 for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
411 uint md_count = md->trap_count(reason);
412 if (md_count != 0) {
413 if (md_count == md->trap_count_limit())
414 md_count += md->overflow_trap_count();
415 uint total_count = C->trap_count(reason);
416 uint old_count = total_count;
417 total_count += md_count;
418 // Saturate the add if it overflows.
419 if (total_count < old_count || total_count < md_count)
420 total_count = (uint)-1;
421 C->set_trap_count(reason, total_count);
422 if (log != NULL)
423 log->elem("observe trap='%s' count='%d' total='%d'",
424 Deoptimization::trap_reason_name(reason),
425 md_count, total_count);
426 }
427 }
428 // Accumulate total sum of decompilations, also.
429 C->set_decompile_count(C->decompile_count() + md->decompile_count());
431 _count_invocations = C->do_count_invocations();
432 _method_data_update = C->do_method_data_update();
434 if (log != NULL && method()->has_exception_handlers()) {
435 log->elem("observe that='has_exception_handlers'");
436 }
438 assert(method()->can_be_compiled(), "Can not parse this method, cutout earlier");
439 assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
441 // Always register dependence if JVMTI is enabled, because
442 // either breakpoint setting or hotswapping of methods may
443 // cause deoptimization.
444 if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
445 C->dependencies()->assert_evol_method(method());
446 }
448 methods_seen++;
450 // Do some special top-level things.
451 if (depth() == 1 && C->is_osr_compilation()) {
452 _entry_bci = C->entry_bci();
453 _flow = method()->get_osr_flow_analysis(osr_bci());
454 if (_flow->failing()) {
455 C->record_method_not_compilable(_flow->failure_reason());
456 #ifndef PRODUCT
457 if (PrintOpto && (Verbose || WizardMode)) {
458 tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
459 if (Verbose) {
460 method()->print_oop();
461 method()->print_codes();
462 _flow->print();
463 }
464 }
465 #endif
466 }
467 _tf = C->tf(); // the OSR entry type is different
468 }
470 #ifdef ASSERT
471 if (depth() == 1) {
472 assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
473 if (C->tf() != tf()) {
474 MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
475 assert(C->env()->system_dictionary_modification_counter_changed(),
476 "Must invalidate if TypeFuncs differ");
477 }
478 } else {
479 assert(!this->is_osr_parse(), "no recursive OSR");
480 }
481 #endif
483 methods_parsed++;
484 #ifndef PRODUCT
485 // add method size here to guarantee that inlined methods are added too
486 if (TimeCompiler)
487 _total_bytes_compiled += method()->code_size();
489 show_parse_info();
490 #endif
492 if (failing()) {
493 if (log) log->done("parse");
494 return;
495 }
497 gvn().set_type(root(), root()->bottom_type());
498 gvn().transform(top());
500 // Import the results of the ciTypeFlow.
501 init_blocks();
503 // Merge point for all normal exits
504 build_exits();
506 // Setup the initial JVM state map.
507 SafePointNode* entry_map = create_entry_map();
509 // Check for bailouts during map initialization
510 if (failing() || entry_map == NULL) {
511 if (log) log->done("parse");
512 return;
513 }
515 Node_Notes* caller_nn = C->default_node_notes();
516 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
517 if (DebugInlinedCalls || depth() == 1) {
518 C->set_default_node_notes(make_node_notes(caller_nn));
519 }
521 if (is_osr_parse()) {
522 Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
523 entry_map->set_req(TypeFunc::Parms+0, top());
524 set_map(entry_map);
525 load_interpreter_state(osr_buf);
526 } else {
527 set_map(entry_map);
528 do_method_entry();
529 }
531 // Check for bailouts during method entry.
532 if (failing()) {
533 if (log) log->done("parse");
534 C->set_default_node_notes(caller_nn);
535 return;
536 }
538 entry_map = map(); // capture any changes performed by method setup code
539 assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
541 // We begin parsing as if we have just encountered a jump to the
542 // method entry.
543 Block* entry_block = start_block();
544 assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
545 set_map_clone(entry_map);
546 merge_common(entry_block, entry_block->next_path_num());
548 #ifndef PRODUCT
549 BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
550 set_parse_histogram( parse_histogram_obj );
551 #endif
553 // Parse all the basic blocks.
554 do_all_blocks();
556 C->set_default_node_notes(caller_nn);
558 // Check for bailouts during conversion to graph
559 if (failing()) {
560 if (log) log->done("parse");
561 return;
562 }
564 // Fix up all exiting control flow.
565 set_map(entry_map);
566 do_exits();
568 if (log) log->done("parse nodes='%d' memory='%d'",
569 C->unique(), C->node_arena()->used());
570 }
572 //---------------------------do_all_blocks-------------------------------------
573 void Parse::do_all_blocks() {
574 bool has_irreducible = flow()->has_irreducible_entry();
576 // Walk over all blocks in Reverse Post-Order.
577 while (true) {
578 bool progress = false;
579 for (int rpo = 0; rpo < block_count(); rpo++) {
580 Block* block = rpo_at(rpo);
582 if (block->is_parsed()) continue;
584 if (!block->is_merged()) {
585 // Dead block, no state reaches this block
586 continue;
587 }
589 // Prepare to parse this block.
590 load_state_from(block);
592 if (stopped()) {
593 // Block is dead.
594 continue;
595 }
597 blocks_parsed++;
599 progress = true;
600 if (block->is_loop_head() || block->is_handler() || has_irreducible && !block->is_ready()) {
601 // Not all preds have been parsed. We must build phis everywhere.
602 // (Note that dead locals do not get phis built, ever.)
603 ensure_phis_everywhere();
605 // Leave behind an undisturbed copy of the map, for future merges.
606 set_map(clone_map());
607 }
609 if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
610 // In the absence of irreducible loops, the Region and Phis
611 // associated with a merge that doesn't involve a backedge can
612 // be simplified now since the RPO parsing order guarantees
613 // that any path which was supposed to reach here has already
614 // been parsed or must be dead.
615 Node* c = control();
616 Node* result = _gvn.transform_no_reclaim(control());
617 if (c != result && TraceOptoParse) {
618 tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
619 }
620 if (result != top()) {
621 record_for_igvn(result);
622 }
623 }
625 // Parse the block.
626 do_one_block();
628 // Check for bailouts.
629 if (failing()) return;
630 }
632 // with irreducible loops multiple passes might be necessary to parse everything
633 if (!has_irreducible || !progress) {
634 break;
635 }
636 }
638 blocks_seen += block_count();
640 #ifndef PRODUCT
641 // Make sure there are no half-processed blocks remaining.
642 // Every remaining unprocessed block is dead and may be ignored now.
643 for (int rpo = 0; rpo < block_count(); rpo++) {
644 Block* block = rpo_at(rpo);
645 if (!block->is_parsed()) {
646 if (TraceOptoParse) {
647 tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
648 }
649 assert(!block->is_merged(), "no half-processed blocks");
650 }
651 }
652 #endif
653 }
655 //-------------------------------build_exits----------------------------------
656 // Build normal and exceptional exit merge points.
657 void Parse::build_exits() {
658 // make a clone of caller to prevent sharing of side-effects
659 _exits.set_map(_exits.clone_map());
660 _exits.clean_stack(_exits.sp());
661 _exits.sync_jvms();
663 RegionNode* region = new (C, 1) RegionNode(1);
664 record_for_igvn(region);
665 gvn().set_type_bottom(region);
666 _exits.set_control(region);
668 // Note: iophi and memphi are not transformed until do_exits.
669 Node* iophi = new (C, region->req()) PhiNode(region, Type::ABIO);
670 Node* memphi = new (C, region->req()) PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
671 _exits.set_i_o(iophi);
672 _exits.set_all_memory(memphi);
674 // Add a return value to the exit state. (Do not push it yet.)
675 if (tf()->range()->cnt() > TypeFunc::Parms) {
676 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
677 // Don't "bind" an unloaded return klass to the ret_phi. If the klass
678 // becomes loaded during the subsequent parsing, the loaded and unloaded
679 // types will not join when we transform and push in do_exits().
680 const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
681 if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
682 ret_type = TypeOopPtr::BOTTOM;
683 }
684 int ret_size = type2size[ret_type->basic_type()];
685 Node* ret_phi = new (C, region->req()) PhiNode(region, ret_type);
686 _exits.ensure_stack(ret_size);
687 assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
688 assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
689 _exits.set_argument(0, ret_phi); // here is where the parser finds it
690 // Note: ret_phi is not yet pushed, until do_exits.
691 }
692 }
695 //----------------------------build_start_state-------------------------------
696 // Construct a state which contains only the incoming arguments from an
697 // unknown caller. The method & bci will be NULL & InvocationEntryBci.
698 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
699 int arg_size = tf->domain()->cnt();
700 int max_size = MAX2(arg_size, (int)tf->range()->cnt());
701 JVMState* jvms = new (this) JVMState(max_size - TypeFunc::Parms);
702 SafePointNode* map = new (this, max_size) SafePointNode(max_size, NULL);
703 record_for_igvn(map);
704 assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
705 Node_Notes* old_nn = default_node_notes();
706 if (old_nn != NULL && has_method()) {
707 Node_Notes* entry_nn = old_nn->clone(this);
708 JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
709 entry_jvms->set_offsets(0);
710 entry_jvms->set_bci(entry_bci());
711 entry_nn->set_jvms(entry_jvms);
712 set_default_node_notes(entry_nn);
713 }
714 uint i;
715 for (i = 0; i < (uint)arg_size; i++) {
716 Node* parm = initial_gvn()->transform(new (this, 1) ParmNode(start, i));
717 map->init_req(i, parm);
718 // Record all these guys for later GVN.
719 record_for_igvn(parm);
720 }
721 for (; i < map->req(); i++) {
722 map->init_req(i, top());
723 }
724 assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
725 set_default_node_notes(old_nn);
726 map->set_jvms(jvms);
727 jvms->set_map(map);
728 return jvms;
729 }
731 //-----------------------------make_node_notes---------------------------------
732 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
733 if (caller_nn == NULL) return NULL;
734 Node_Notes* nn = caller_nn->clone(C);
735 JVMState* caller_jvms = nn->jvms();
736 JVMState* jvms = new (C) JVMState(method(), caller_jvms);
737 jvms->set_offsets(0);
738 jvms->set_bci(_entry_bci);
739 nn->set_jvms(jvms);
740 return nn;
741 }
744 //--------------------------return_values--------------------------------------
745 void Compile::return_values(JVMState* jvms) {
746 GraphKit kit(jvms);
747 Node* ret = new (this, TypeFunc::Parms) ReturnNode(TypeFunc::Parms,
748 kit.control(),
749 kit.i_o(),
750 kit.reset_memory(),
751 kit.frameptr(),
752 kit.returnadr());
753 // Add zero or 1 return values
754 int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
755 if (ret_size > 0) {
756 kit.inc_sp(-ret_size); // pop the return value(s)
757 kit.sync_jvms();
758 ret->add_req(kit.argument(0));
759 // Note: The second dummy edge is not needed by a ReturnNode.
760 }
761 // bind it to root
762 root()->add_req(ret);
763 record_for_igvn(ret);
764 initial_gvn()->transform_no_reclaim(ret);
765 }
767 //------------------------rethrow_exceptions-----------------------------------
768 // Bind all exception states in the list into a single RethrowNode.
769 void Compile::rethrow_exceptions(JVMState* jvms) {
770 GraphKit kit(jvms);
771 if (!kit.has_exceptions()) return; // nothing to generate
772 // Load my combined exception state into the kit, with all phis transformed:
773 SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
774 Node* ex_oop = kit.use_exception_state(ex_map);
775 RethrowNode* exit = new (this, TypeFunc::Parms + 1) RethrowNode(kit.control(),
776 kit.i_o(), kit.reset_memory(),
777 kit.frameptr(), kit.returnadr(),
778 // like a return but with exception input
779 ex_oop);
780 // bind to root
781 root()->add_req(exit);
782 record_for_igvn(exit);
783 initial_gvn()->transform_no_reclaim(exit);
784 }
786 bool Parse::can_rerun_bytecode() {
787 switch (bc()) {
788 case Bytecodes::_ldc:
789 case Bytecodes::_ldc_w:
790 case Bytecodes::_ldc2_w:
791 case Bytecodes::_getfield:
792 case Bytecodes::_putfield:
793 case Bytecodes::_getstatic:
794 case Bytecodes::_putstatic:
795 case Bytecodes::_arraylength:
796 case Bytecodes::_baload:
797 case Bytecodes::_caload:
798 case Bytecodes::_iaload:
799 case Bytecodes::_saload:
800 case Bytecodes::_faload:
801 case Bytecodes::_aaload:
802 case Bytecodes::_laload:
803 case Bytecodes::_daload:
804 case Bytecodes::_bastore:
805 case Bytecodes::_castore:
806 case Bytecodes::_iastore:
807 case Bytecodes::_sastore:
808 case Bytecodes::_fastore:
809 case Bytecodes::_aastore:
810 case Bytecodes::_lastore:
811 case Bytecodes::_dastore:
812 case Bytecodes::_irem:
813 case Bytecodes::_idiv:
814 case Bytecodes::_lrem:
815 case Bytecodes::_ldiv:
816 case Bytecodes::_frem:
817 case Bytecodes::_fdiv:
818 case Bytecodes::_drem:
819 case Bytecodes::_ddiv:
820 case Bytecodes::_checkcast:
821 case Bytecodes::_instanceof:
822 case Bytecodes::_athrow:
823 case Bytecodes::_anewarray:
824 case Bytecodes::_newarray:
825 case Bytecodes::_multianewarray:
826 case Bytecodes::_new:
827 case Bytecodes::_monitorenter: // can re-run initial null check, only
828 case Bytecodes::_return:
829 return true;
830 break;
832 case Bytecodes::_invokestatic:
833 case Bytecodes::_invokedynamic:
834 case Bytecodes::_invokespecial:
835 case Bytecodes::_invokevirtual:
836 case Bytecodes::_invokeinterface:
837 return false;
838 break;
840 default:
841 assert(false, "unexpected bytecode produced an exception");
842 return true;
843 }
844 }
846 //---------------------------do_exceptions-------------------------------------
847 // Process exceptions arising from the current bytecode.
848 // Send caught exceptions to the proper handler within this method.
849 // Unhandled exceptions feed into _exit.
850 void Parse::do_exceptions() {
851 if (!has_exceptions()) return;
853 if (failing()) {
854 // Pop them all off and throw them away.
855 while (pop_exception_state() != NULL) ;
856 return;
857 }
859 // Make sure we can classify this bytecode if we need to.
860 debug_only(can_rerun_bytecode());
862 PreserveJVMState pjvms(this, false);
864 SafePointNode* ex_map;
865 while ((ex_map = pop_exception_state()) != NULL) {
866 if (!method()->has_exception_handlers()) {
867 // Common case: Transfer control outward.
868 // Doing it this early allows the exceptions to common up
869 // even between adjacent method calls.
870 throw_to_exit(ex_map);
871 } else {
872 // Have to look at the exception first.
873 assert(stopped(), "catch_inline_exceptions trashes the map");
874 catch_inline_exceptions(ex_map);
875 stop_and_kill_map(); // we used up this exception state; kill it
876 }
877 }
879 // We now return to our regularly scheduled program:
880 }
882 //---------------------------throw_to_exit-------------------------------------
883 // Merge the given map into an exception exit from this method.
884 // The exception exit will handle any unlocking of receiver.
885 // The ex_oop must be saved within the ex_map, unlike merge_exception.
886 void Parse::throw_to_exit(SafePointNode* ex_map) {
887 // Pop the JVMS to (a copy of) the caller.
888 GraphKit caller;
889 caller.set_map_clone(_caller->map());
890 caller.set_bci(_caller->bci());
891 caller.set_sp(_caller->sp());
892 // Copy out the standard machine state:
893 for (uint i = 0; i < TypeFunc::Parms; i++) {
894 caller.map()->set_req(i, ex_map->in(i));
895 }
896 // ...and the exception:
897 Node* ex_oop = saved_ex_oop(ex_map);
898 SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
899 // Finally, collect the new exception state in my exits:
900 _exits.add_exception_state(caller_ex_map);
901 }
903 //------------------------------do_exits---------------------------------------
904 void Parse::do_exits() {
905 set_parse_bci(InvocationEntryBci);
907 // Now peephole on the return bits
908 Node* region = _exits.control();
909 _exits.set_control(gvn().transform(region));
911 Node* iophi = _exits.i_o();
912 _exits.set_i_o(gvn().transform(iophi));
914 if (wrote_final()) {
915 // This method (which must be a constructor by the rules of Java)
916 // wrote a final. The effects of all initializations must be
917 // committed to memory before any code after the constructor
918 // publishes the reference to the newly constructor object.
919 // Rather than wait for the publication, we simply block the
920 // writes here. Rather than put a barrier on only those writes
921 // which are required to complete, we force all writes to complete.
922 //
923 // "All bets are off" unless the first publication occurs after a
924 // normal return from the constructor. We do not attempt to detect
925 // such unusual early publications. But no barrier is needed on
926 // exceptional returns, since they cannot publish normally.
927 //
928 _exits.insert_mem_bar(Op_MemBarRelease);
929 #ifndef PRODUCT
930 if (PrintOpto && (Verbose || WizardMode)) {
931 method()->print_name();
932 tty->print_cr(" writes finals and needs a memory barrier");
933 }
934 #endif
935 }
937 for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
938 // transform each slice of the original memphi:
939 mms.set_memory(_gvn.transform(mms.memory()));
940 }
942 if (tf()->range()->cnt() > TypeFunc::Parms) {
943 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
944 Node* ret_phi = _gvn.transform( _exits.argument(0) );
945 assert(_exits.control()->is_top() || !_gvn.type(ret_phi)->empty(), "return value must be well defined");
946 _exits.push_node(ret_type->basic_type(), ret_phi);
947 }
949 // Note: Logic for creating and optimizing the ReturnNode is in Compile.
951 // Unlock along the exceptional paths.
952 // This is done late so that we can common up equivalent exceptions
953 // (e.g., null checks) arising from multiple points within this method.
954 // See GraphKit::add_exception_state, which performs the commoning.
955 bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
957 // record exit from a method if compiled while Dtrace is turned on.
958 if (do_synch || C->env()->dtrace_method_probes()) {
959 // First move the exception list out of _exits:
960 GraphKit kit(_exits.transfer_exceptions_into_jvms());
961 SafePointNode* normal_map = kit.map(); // keep this guy safe
962 // Now re-collect the exceptions into _exits:
963 SafePointNode* ex_map;
964 while ((ex_map = kit.pop_exception_state()) != NULL) {
965 Node* ex_oop = kit.use_exception_state(ex_map);
966 // Force the exiting JVM state to have this method at InvocationEntryBci.
967 // The exiting JVM state is otherwise a copy of the calling JVMS.
968 JVMState* caller = kit.jvms();
969 JVMState* ex_jvms = caller->clone_shallow(C);
970 ex_jvms->set_map(kit.clone_map());
971 ex_jvms->map()->set_jvms(ex_jvms);
972 ex_jvms->set_bci( InvocationEntryBci);
973 kit.set_jvms(ex_jvms);
974 if (do_synch) {
975 // Add on the synchronized-method box/object combo
976 kit.map()->push_monitor(_synch_lock);
977 // Unlock!
978 kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
979 }
980 if (C->env()->dtrace_method_probes()) {
981 kit.make_dtrace_method_exit(method());
982 }
983 // Done with exception-path processing.
984 ex_map = kit.make_exception_state(ex_oop);
985 assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
986 // Pop the last vestige of this method:
987 ex_map->set_jvms(caller->clone_shallow(C));
988 ex_map->jvms()->set_map(ex_map);
989 _exits.push_exception_state(ex_map);
990 }
991 assert(_exits.map() == normal_map, "keep the same return state");
992 }
994 {
995 // Capture very early exceptions (receiver null checks) from caller JVMS
996 GraphKit caller(_caller);
997 SafePointNode* ex_map;
998 while ((ex_map = caller.pop_exception_state()) != NULL) {
999 _exits.add_exception_state(ex_map);
1000 }
1001 }
1002 }
1004 //-----------------------------create_entry_map-------------------------------
1005 // Initialize our parser map to contain the types at method entry.
1006 // For OSR, the map contains a single RawPtr parameter.
1007 // Initial monitor locking for sync. methods is performed by do_method_entry.
1008 SafePointNode* Parse::create_entry_map() {
1009 // Check for really stupid bail-out cases.
1010 uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1011 if (len >= 32760) {
1012 C->record_method_not_compilable_all_tiers("too many local variables");
1013 return NULL;
1014 }
1016 // If this is an inlined method, we may have to do a receiver null check.
1017 if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1018 GraphKit kit(_caller);
1019 kit.null_check_receiver(method());
1020 _caller = kit.transfer_exceptions_into_jvms();
1021 if (kit.stopped()) {
1022 _exits.add_exception_states_from(_caller);
1023 _exits.set_jvms(_caller);
1024 return NULL;
1025 }
1026 }
1028 assert(method() != NULL, "parser must have a method");
1030 // Create an initial safepoint to hold JVM state during parsing
1031 JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1032 set_map(new (C, len) SafePointNode(len, jvms));
1033 jvms->set_map(map());
1034 record_for_igvn(map());
1035 assert(jvms->endoff() == len, "correct jvms sizing");
1037 SafePointNode* inmap = _caller->map();
1038 assert(inmap != NULL, "must have inmap");
1040 uint i;
1042 // Pass thru the predefined input parameters.
1043 for (i = 0; i < TypeFunc::Parms; i++) {
1044 map()->init_req(i, inmap->in(i));
1045 }
1047 if (depth() == 1) {
1048 assert(map()->memory()->Opcode() == Op_Parm, "");
1049 // Insert the memory aliasing node
1050 set_all_memory(reset_memory());
1051 }
1052 assert(merged_memory(), "");
1054 // Now add the locals which are initially bound to arguments:
1055 uint arg_size = tf()->domain()->cnt();
1056 ensure_stack(arg_size - TypeFunc::Parms); // OSR methods have funny args
1057 for (i = TypeFunc::Parms; i < arg_size; i++) {
1058 map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1059 }
1061 // Clear out the rest of the map (locals and stack)
1062 for (i = arg_size; i < len; i++) {
1063 map()->init_req(i, top());
1064 }
1066 SafePointNode* entry_map = stop();
1067 return entry_map;
1068 }
1070 //-----------------------------do_method_entry--------------------------------
1071 // Emit any code needed in the pseudo-block before BCI zero.
1072 // The main thing to do is lock the receiver of a synchronized method.
1073 void Parse::do_method_entry() {
1074 set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1075 set_sp(0); // Java Stack Pointer
1077 NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1079 if (C->env()->dtrace_method_probes()) {
1080 make_dtrace_method_entry(method());
1081 }
1083 // If the method is synchronized, we need to construct a lock node, attach
1084 // it to the Start node, and pin it there.
1085 if (method()->is_synchronized()) {
1086 // Insert a FastLockNode right after the Start which takes as arguments
1087 // the current thread pointer, the "this" pointer & the address of the
1088 // stack slot pair used for the lock. The "this" pointer is a projection
1089 // off the start node, but the locking spot has to be constructed by
1090 // creating a ConLNode of 0, and boxing it with a BoxLockNode. The BoxLockNode
1091 // becomes the second argument to the FastLockNode call. The
1092 // FastLockNode becomes the new control parent to pin it to the start.
1094 // Setup Object Pointer
1095 Node *lock_obj = NULL;
1096 if(method()->is_static()) {
1097 ciInstance* mirror = _method->holder()->java_mirror();
1098 const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1099 lock_obj = makecon(t_lock);
1100 } else { // Else pass the "this" pointer,
1101 lock_obj = local(0); // which is Parm0 from StartNode
1102 }
1103 // Clear out dead values from the debug info.
1104 kill_dead_locals();
1105 // Build the FastLockNode
1106 _synch_lock = shared_lock(lock_obj);
1107 }
1109 if (depth() == 1) {
1110 increment_and_test_invocation_counter(Tier2CompileThreshold);
1111 }
1112 }
1114 //------------------------------init_blocks------------------------------------
1115 // Initialize our parser map to contain the types/monitors at method entry.
1116 void Parse::init_blocks() {
1117 // Create the blocks.
1118 _block_count = flow()->block_count();
1119 _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
1120 Copy::zero_to_bytes(_blocks, sizeof(Block)*_block_count);
1122 int rpo;
1124 // Initialize the structs.
1125 for (rpo = 0; rpo < block_count(); rpo++) {
1126 Block* block = rpo_at(rpo);
1127 block->init_node(this, rpo);
1128 }
1130 // Collect predecessor and successor information.
1131 for (rpo = 0; rpo < block_count(); rpo++) {
1132 Block* block = rpo_at(rpo);
1133 block->init_graph(this);
1134 }
1135 }
1137 //-------------------------------init_node-------------------------------------
1138 void Parse::Block::init_node(Parse* outer, int rpo) {
1139 _flow = outer->flow()->rpo_at(rpo);
1140 _pred_count = 0;
1141 _preds_parsed = 0;
1142 _count = 0;
1143 assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
1144 assert(!(is_merged() || is_parsed() || is_handler()), "sanity");
1145 assert(_live_locals.size() == 0, "sanity");
1147 // entry point has additional predecessor
1148 if (flow()->is_start()) _pred_count++;
1149 assert(flow()->is_start() == (this == outer->start_block()), "");
1150 }
1152 //-------------------------------init_graph------------------------------------
1153 void Parse::Block::init_graph(Parse* outer) {
1154 // Create the successor list for this parser block.
1155 GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
1156 GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
1157 int ns = tfs->length();
1158 int ne = tfe->length();
1159 _num_successors = ns;
1160 _all_successors = ns+ne;
1161 _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
1162 int p = 0;
1163 for (int i = 0; i < ns+ne; i++) {
1164 ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
1165 Block* block2 = outer->rpo_at(tf2->rpo());
1166 _successors[i] = block2;
1168 // Accumulate pred info for the other block, too.
1169 if (i < ns) {
1170 block2->_pred_count++;
1171 } else {
1172 block2->_is_handler = true;
1173 }
1175 #ifdef ASSERT
1176 // A block's successors must be distinguishable by BCI.
1177 // That is, no bytecode is allowed to branch to two different
1178 // clones of the same code location.
1179 for (int j = 0; j < i; j++) {
1180 Block* block1 = _successors[j];
1181 if (block1 == block2) continue; // duplicates are OK
1182 assert(block1->start() != block2->start(), "successors have unique bcis");
1183 }
1184 #endif
1185 }
1187 // Note: We never call next_path_num along exception paths, so they
1188 // never get processed as "ready". Also, the input phis of exception
1189 // handlers get specially processed, so that
1190 }
1192 //---------------------------successor_for_bci---------------------------------
1193 Parse::Block* Parse::Block::successor_for_bci(int bci) {
1194 for (int i = 0; i < all_successors(); i++) {
1195 Block* block2 = successor_at(i);
1196 if (block2->start() == bci) return block2;
1197 }
1198 // We can actually reach here if ciTypeFlow traps out a block
1199 // due to an unloaded class, and concurrently with compilation the
1200 // class is then loaded, so that a later phase of the parser is
1201 // able to see more of the bytecode CFG. Or, the flow pass and
1202 // the parser can have a minor difference of opinion about executability
1203 // of bytecodes. For example, "obj.field = null" is executable even
1204 // if the field's type is an unloaded class; the flow pass used to
1205 // make a trap for such code.
1206 return NULL;
1207 }
1210 //-----------------------------stack_type_at-----------------------------------
1211 const Type* Parse::Block::stack_type_at(int i) const {
1212 return get_type(flow()->stack_type_at(i));
1213 }
1216 //-----------------------------local_type_at-----------------------------------
1217 const Type* Parse::Block::local_type_at(int i) const {
1218 // Make dead locals fall to bottom.
1219 if (_live_locals.size() == 0) {
1220 MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
1221 // This bitmap can be zero length if we saw a breakpoint.
1222 // In such cases, pretend they are all live.
1223 ((Block*)this)->_live_locals = live_locals;
1224 }
1225 if (_live_locals.size() > 0 && !_live_locals.at(i))
1226 return Type::BOTTOM;
1228 return get_type(flow()->local_type_at(i));
1229 }
1232 #ifndef PRODUCT
1234 //----------------------------name_for_bc--------------------------------------
1235 // helper method for BytecodeParseHistogram
1236 static const char* name_for_bc(int i) {
1237 return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
1238 }
1240 //----------------------------BytecodeParseHistogram------------------------------------
1241 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
1242 _parser = p;
1243 _compiler = c;
1244 if( ! _initialized ) { _initialized = true; reset(); }
1245 }
1247 //----------------------------current_count------------------------------------
1248 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
1249 switch( bph_type ) {
1250 case BPH_transforms: { return _parser->gvn().made_progress(); }
1251 case BPH_values: { return _parser->gvn().made_new_values(); }
1252 default: { ShouldNotReachHere(); return 0; }
1253 }
1254 }
1256 //----------------------------initialized--------------------------------------
1257 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
1259 //----------------------------reset--------------------------------------------
1260 void Parse::BytecodeParseHistogram::reset() {
1261 int i = Bytecodes::number_of_codes;
1262 while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
1263 }
1265 //----------------------------set_initial_state--------------------------------
1266 // Record info when starting to parse one bytecode
1267 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
1268 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1269 _initial_bytecode = bc;
1270 _initial_node_count = _compiler->unique();
1271 _initial_transforms = current_count(BPH_transforms);
1272 _initial_values = current_count(BPH_values);
1273 }
1274 }
1276 //----------------------------record_change--------------------------------
1277 // Record results of parsing one bytecode
1278 void Parse::BytecodeParseHistogram::record_change() {
1279 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1280 ++_bytecodes_parsed[_initial_bytecode];
1281 _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
1282 _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
1283 _new_values [_initial_bytecode] += (current_count(BPH_values) - _initial_values);
1284 }
1285 }
1288 //----------------------------print--------------------------------------------
1289 void Parse::BytecodeParseHistogram::print(float cutoff) {
1290 ResourceMark rm;
1291 // print profile
1292 int total = 0;
1293 int i = 0;
1294 for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
1295 int abs_sum = 0;
1296 tty->cr(); //0123456789012345678901234567890123456789012345678901234567890123456789
1297 tty->print_cr("Histogram of %d parsed bytecodes:", total);
1298 if( total == 0 ) { return; }
1299 tty->cr();
1300 tty->print_cr("absolute: count of compiled bytecodes of this type");
1301 tty->print_cr("relative: percentage contribution to compiled nodes");
1302 tty->print_cr("nodes : Average number of nodes constructed per bytecode");
1303 tty->print_cr("rnodes : Significance towards total nodes constructed, (nodes*relative)");
1304 tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
1305 tty->print_cr("values : Average number of node values improved per bytecode");
1306 tty->print_cr("name : Bytecode name");
1307 tty->cr();
1308 tty->print_cr(" absolute relative nodes rnodes transforms values name");
1309 tty->print_cr("----------------------------------------------------------------------");
1310 while (--i > 0) {
1311 int abs = _bytecodes_parsed[i];
1312 float rel = abs * 100.0F / total;
1313 float nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
1314 float rnodes = _bytecodes_parsed[i] == 0 ? 0 : rel * nodes;
1315 float xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
1316 float values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values [i])/_bytecodes_parsed[i];
1317 if (cutoff <= rel) {
1318 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));
1319 abs_sum += abs;
1320 }
1321 }
1322 tty->print_cr("----------------------------------------------------------------------");
1323 float rel_sum = abs_sum * 100.0F / total;
1324 tty->print_cr("%10d %7.2f%% (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
1325 tty->print_cr("----------------------------------------------------------------------");
1326 tty->cr();
1327 }
1328 #endif
1330 //----------------------------load_state_from----------------------------------
1331 // Load block/map/sp. But not do not touch iter/bci.
1332 void Parse::load_state_from(Block* block) {
1333 set_block(block);
1334 // load the block's JVM state:
1335 set_map(block->start_map());
1336 set_sp( block->start_sp());
1337 }
1340 //-----------------------------record_state------------------------------------
1341 void Parse::Block::record_state(Parse* p) {
1342 assert(!is_merged(), "can only record state once, on 1st inflow");
1343 assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
1344 set_start_map(p->stop());
1345 }
1348 //------------------------------do_one_block-----------------------------------
1349 void Parse::do_one_block() {
1350 if (TraceOptoParse) {
1351 Block *b = block();
1352 int ns = b->num_successors();
1353 int nt = b->all_successors();
1355 tty->print("Parsing block #%d at bci [%d,%d), successors: ",
1356 block()->rpo(), block()->start(), block()->limit());
1357 for (int i = 0; i < nt; i++) {
1358 tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
1359 }
1360 if (b->is_loop_head()) tty->print(" lphd");
1361 tty->print_cr("");
1362 }
1364 assert(block()->is_merged(), "must be merged before being parsed");
1365 block()->mark_parsed();
1366 ++_blocks_parsed;
1368 // Set iterator to start of block.
1369 iter().reset_to_bci(block()->start());
1371 CompileLog* log = C->log();
1373 // Parse bytecodes
1374 while (!stopped() && !failing()) {
1375 iter().next();
1377 // Learn the current bci from the iterator:
1378 set_parse_bci(iter().cur_bci());
1380 if (bci() == block()->limit()) {
1381 // Do not walk into the next block until directed by do_all_blocks.
1382 merge(bci());
1383 break;
1384 }
1385 assert(bci() < block()->limit(), "bci still in block");
1387 if (log != NULL) {
1388 // Output an optional context marker, to help place actions
1389 // that occur during parsing of this BC. If there is no log
1390 // output until the next context string, this context string
1391 // will be silently ignored.
1392 log->context()->reset();
1393 log->context()->print_cr("<bc code='%d' bci='%d'/>", (int)bc(), bci());
1394 }
1396 if (block()->has_trap_at(bci())) {
1397 // We must respect the flow pass's traps, because it will refuse
1398 // to produce successors for trapping blocks.
1399 int trap_index = block()->flow()->trap_index();
1400 assert(trap_index != 0, "trap index must be valid");
1401 uncommon_trap(trap_index);
1402 break;
1403 }
1405 NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1407 #ifdef ASSERT
1408 int pre_bc_sp = sp();
1409 int inputs, depth;
1410 bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1411 assert(!have_se || pre_bc_sp >= inputs, "have enough stack to execute this BC");
1412 #endif //ASSERT
1414 do_one_bytecode();
1416 assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth, "correct depth prediction");
1418 do_exceptions();
1420 NOT_PRODUCT( parse_histogram()->record_change(); );
1422 if (log != NULL) log->context()->reset(); // done w/ this one
1424 // Fall into next bytecode. Each bytecode normally has 1 sequential
1425 // successor which is typically made ready by visiting this bytecode.
1426 // If the successor has several predecessors, then it is a merge
1427 // point, starts a new basic block, and is handled like other basic blocks.
1428 }
1429 }
1432 //------------------------------merge------------------------------------------
1433 void Parse::set_parse_bci(int bci) {
1434 set_bci(bci);
1435 Node_Notes* nn = C->default_node_notes();
1436 if (nn == NULL) return;
1438 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
1439 if (!DebugInlinedCalls && depth() > 1) {
1440 return;
1441 }
1443 // Update the JVMS annotation, if present.
1444 JVMState* jvms = nn->jvms();
1445 if (jvms != NULL && jvms->bci() != bci) {
1446 // Update the JVMS.
1447 jvms = jvms->clone_shallow(C);
1448 jvms->set_bci(bci);
1449 nn->set_jvms(jvms);
1450 }
1451 }
1453 //------------------------------merge------------------------------------------
1454 // Merge the current mapping into the basic block starting at bci
1455 void Parse::merge(int target_bci) {
1456 Block* target = successor_for_bci(target_bci);
1457 if (target == NULL) { handle_missing_successor(target_bci); return; }
1458 assert(!target->is_ready(), "our arrival must be expected");
1459 int pnum = target->next_path_num();
1460 merge_common(target, pnum);
1461 }
1463 //-------------------------merge_new_path--------------------------------------
1464 // Merge the current mapping into the basic block, using a new path
1465 void Parse::merge_new_path(int target_bci) {
1466 Block* target = successor_for_bci(target_bci);
1467 if (target == NULL) { handle_missing_successor(target_bci); return; }
1468 assert(!target->is_ready(), "new path into frozen graph");
1469 int pnum = target->add_new_path();
1470 merge_common(target, pnum);
1471 }
1473 //-------------------------merge_exception-------------------------------------
1474 // Merge the current mapping into the basic block starting at bci
1475 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
1476 void Parse::merge_exception(int target_bci) {
1477 assert(sp() == 1, "must have only the throw exception on the stack");
1478 Block* target = successor_for_bci(target_bci);
1479 if (target == NULL) { handle_missing_successor(target_bci); return; }
1480 assert(target->is_handler(), "exceptions are handled by special blocks");
1481 int pnum = target->add_new_path();
1482 merge_common(target, pnum);
1483 }
1485 //--------------------handle_missing_successor---------------------------------
1486 void Parse::handle_missing_successor(int target_bci) {
1487 #ifndef PRODUCT
1488 Block* b = block();
1489 int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1490 tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1491 #endif
1492 ShouldNotReachHere();
1493 }
1495 //--------------------------merge_common---------------------------------------
1496 void Parse::merge_common(Parse::Block* target, int pnum) {
1497 if (TraceOptoParse) {
1498 tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1499 }
1501 // Zap extra stack slots to top
1502 assert(sp() == target->start_sp(), "");
1503 clean_stack(sp());
1505 if (!target->is_merged()) { // No prior mapping at this bci
1506 if (TraceOptoParse) { tty->print(" with empty state"); }
1508 // If this path is dead, do not bother capturing it as a merge.
1509 // It is "as if" we had 1 fewer predecessors from the beginning.
1510 if (stopped()) {
1511 if (TraceOptoParse) tty->print_cr(", but path is dead and doesn't count");
1512 return;
1513 }
1515 // Record that a new block has been merged.
1516 ++_blocks_merged;
1518 // Make a region if we know there are multiple or unpredictable inputs.
1519 // (Also, if this is a plain fall-through, we might see another region,
1520 // which must not be allowed into this block's map.)
1521 if (pnum > PhiNode::Input // Known multiple inputs.
1522 || target->is_handler() // These have unpredictable inputs.
1523 || target->is_loop_head() // Known multiple inputs
1524 || control()->is_Region()) { // We must hide this guy.
1525 // Add a Region to start the new basic block. Phis will be added
1526 // later lazily.
1527 int edges = target->pred_count();
1528 if (edges < pnum) edges = pnum; // might be a new path!
1529 Node *r = new (C, edges+1) RegionNode(edges+1);
1530 gvn().set_type(r, Type::CONTROL);
1531 record_for_igvn(r);
1532 // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1533 // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1534 r->init_req(pnum, control());
1535 set_control(r);
1536 }
1538 // Convert the existing Parser mapping into a mapping at this bci.
1539 store_state_to(target);
1540 assert(target->is_merged(), "do not come here twice");
1542 } else { // Prior mapping at this bci
1543 if (TraceOptoParse) { tty->print(" with previous state"); }
1545 // We must not manufacture more phis if the target is already parsed.
1546 bool nophi = target->is_parsed();
1548 SafePointNode* newin = map();// Hang on to incoming mapping
1549 Block* save_block = block(); // Hang on to incoming block;
1550 load_state_from(target); // Get prior mapping
1552 assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1553 assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1554 assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1555 assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1557 // Iterate over my current mapping and the old mapping.
1558 // Where different, insert Phi functions.
1559 // Use any existing Phi functions.
1560 assert(control()->is_Region(), "must be merging to a region");
1561 RegionNode* r = control()->as_Region();
1563 // Compute where to merge into
1564 // Merge incoming control path
1565 r->init_req(pnum, newin->control());
1567 if (pnum == 1) { // Last merge for this Region?
1568 if (!block()->flow()->is_irreducible_entry()) {
1569 Node* result = _gvn.transform_no_reclaim(r);
1570 if (r != result && TraceOptoParse) {
1571 tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1572 }
1573 }
1574 record_for_igvn(r);
1575 }
1577 // Update all the non-control inputs to map:
1578 assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1579 bool check_elide_phi = target->is_SEL_backedge(save_block);
1580 for (uint j = 1; j < newin->req(); j++) {
1581 Node* m = map()->in(j); // Current state of target.
1582 Node* n = newin->in(j); // Incoming change to target state.
1583 PhiNode* phi;
1584 if (m->is_Phi() && m->as_Phi()->region() == r)
1585 phi = m->as_Phi();
1586 else
1587 phi = NULL;
1588 if (m != n) { // Different; must merge
1589 switch (j) {
1590 // Frame pointer and Return Address never changes
1591 case TypeFunc::FramePtr:// Drop m, use the original value
1592 case TypeFunc::ReturnAdr:
1593 break;
1594 case TypeFunc::Memory: // Merge inputs to the MergeMem node
1595 assert(phi == NULL, "the merge contains phis, not vice versa");
1596 merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1597 continue;
1598 default: // All normal stuff
1599 if (phi == NULL) {
1600 if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1601 phi = ensure_phi(j, nophi);
1602 }
1603 }
1604 break;
1605 }
1606 }
1607 // At this point, n might be top if:
1608 // - there is no phi (because TypeFlow detected a conflict), or
1609 // - the corresponding control edges is top (a dead incoming path)
1610 // It is a bug if we create a phi which sees a garbage value on a live path.
1612 if (phi != NULL) {
1613 assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1614 assert(phi->region() == r, "");
1615 phi->set_req(pnum, n); // Then add 'n' to the merge
1616 if (pnum == PhiNode::Input) {
1617 // Last merge for this Phi.
1618 // So far, Phis have had a reasonable type from ciTypeFlow.
1619 // Now _gvn will join that with the meet of current inputs.
1620 // BOTTOM is never permissible here, 'cause pessimistically
1621 // Phis of pointers cannot lose the basic pointer type.
1622 debug_only(const Type* bt1 = phi->bottom_type());
1623 assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1624 map()->set_req(j, _gvn.transform_no_reclaim(phi));
1625 debug_only(const Type* bt2 = phi->bottom_type());
1626 assert(bt2->higher_equal(bt1), "must be consistent with type-flow");
1627 record_for_igvn(phi);
1628 }
1629 }
1630 } // End of for all values to be merged
1632 if (pnum == PhiNode::Input &&
1633 !r->in(0)) { // The occasional useless Region
1634 assert(control() == r, "");
1635 set_control(r->nonnull_req());
1636 }
1638 // newin has been subsumed into the lazy merge, and is now dead.
1639 set_block(save_block);
1641 stop(); // done with this guy, for now
1642 }
1644 if (TraceOptoParse) {
1645 tty->print_cr(" on path %d", pnum);
1646 }
1648 // Done with this parser state.
1649 assert(stopped(), "");
1650 }
1653 //--------------------------merge_memory_edges---------------------------------
1654 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1655 // (nophi means we must not create phis, because we already parsed here)
1656 assert(n != NULL, "");
1657 // Merge the inputs to the MergeMems
1658 MergeMemNode* m = merged_memory();
1660 assert(control()->is_Region(), "must be merging to a region");
1661 RegionNode* r = control()->as_Region();
1663 PhiNode* base = NULL;
1664 MergeMemNode* remerge = NULL;
1665 for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1666 Node *p = mms.force_memory();
1667 Node *q = mms.memory2();
1668 if (mms.is_empty() && nophi) {
1669 // Trouble: No new splits allowed after a loop body is parsed.
1670 // Instead, wire the new split into a MergeMem on the backedge.
1671 // The optimizer will sort it out, slicing the phi.
1672 if (remerge == NULL) {
1673 assert(base != NULL, "");
1674 assert(base->in(0) != NULL, "should not be xformed away");
1675 remerge = MergeMemNode::make(C, base->in(pnum));
1676 gvn().set_type(remerge, Type::MEMORY);
1677 base->set_req(pnum, remerge);
1678 }
1679 remerge->set_memory_at(mms.alias_idx(), q);
1680 continue;
1681 }
1682 assert(!q->is_MergeMem(), "");
1683 PhiNode* phi;
1684 if (p != q) {
1685 phi = ensure_memory_phi(mms.alias_idx(), nophi);
1686 } else {
1687 if (p->is_Phi() && p->as_Phi()->region() == r)
1688 phi = p->as_Phi();
1689 else
1690 phi = NULL;
1691 }
1692 // Insert q into local phi
1693 if (phi != NULL) {
1694 assert(phi->region() == r, "");
1695 p = phi;
1696 phi->set_req(pnum, q);
1697 if (mms.at_base_memory()) {
1698 base = phi; // delay transforming it
1699 } else if (pnum == 1) {
1700 record_for_igvn(phi);
1701 p = _gvn.transform_no_reclaim(phi);
1702 }
1703 mms.set_memory(p);// store back through the iterator
1704 }
1705 }
1706 // Transform base last, in case we must fiddle with remerging.
1707 if (base != NULL && pnum == 1) {
1708 record_for_igvn(base);
1709 m->set_base_memory( _gvn.transform_no_reclaim(base) );
1710 }
1711 }
1714 //------------------------ensure_phis_everywhere-------------------------------
1715 void Parse::ensure_phis_everywhere() {
1716 ensure_phi(TypeFunc::I_O);
1718 // Ensure a phi on all currently known memories.
1719 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
1720 ensure_memory_phi(mms.alias_idx());
1721 debug_only(mms.set_memory()); // keep the iterator happy
1722 }
1724 // Note: This is our only chance to create phis for memory slices.
1725 // If we miss a slice that crops up later, it will have to be
1726 // merged into the base-memory phi that we are building here.
1727 // Later, the optimizer will comb out the knot, and build separate
1728 // phi-loops for each memory slice that matters.
1730 // Monitors must nest nicely and not get confused amongst themselves.
1731 // Phi-ify everything up to the monitors, though.
1732 uint monoff = map()->jvms()->monoff();
1733 uint nof_monitors = map()->jvms()->nof_monitors();
1735 assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
1736 bool check_elide_phi = block()->is_SEL_head();
1737 for (uint i = TypeFunc::Parms; i < monoff; i++) {
1738 if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
1739 ensure_phi(i);
1740 }
1741 }
1743 // Even monitors need Phis, though they are well-structured.
1744 // This is true for OSR methods, and also for the rare cases where
1745 // a monitor object is the subject of a replace_in_map operation.
1746 // See bugs 4426707 and 5043395.
1747 for (uint m = 0; m < nof_monitors; m++) {
1748 ensure_phi(map()->jvms()->monitor_obj_offset(m));
1749 }
1750 }
1753 //-----------------------------add_new_path------------------------------------
1754 // Add a previously unaccounted predecessor to this block.
1755 int Parse::Block::add_new_path() {
1756 // If there is no map, return the lowest unused path number.
1757 if (!is_merged()) return pred_count()+1; // there will be a map shortly
1759 SafePointNode* map = start_map();
1760 if (!map->control()->is_Region())
1761 return pred_count()+1; // there may be a region some day
1762 RegionNode* r = map->control()->as_Region();
1764 // Add new path to the region.
1765 uint pnum = r->req();
1766 r->add_req(NULL);
1768 for (uint i = 1; i < map->req(); i++) {
1769 Node* n = map->in(i);
1770 if (i == TypeFunc::Memory) {
1771 // Ensure a phi on all currently known memories.
1772 for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1773 Node* phi = mms.memory();
1774 if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1775 assert(phi->req() == pnum, "must be same size as region");
1776 phi->add_req(NULL);
1777 }
1778 }
1779 } else {
1780 if (n->is_Phi() && n->as_Phi()->region() == r) {
1781 assert(n->req() == pnum, "must be same size as region");
1782 n->add_req(NULL);
1783 }
1784 }
1785 }
1787 return pnum;
1788 }
1790 //------------------------------ensure_phi-------------------------------------
1791 // Turn the idx'th entry of the current map into a Phi
1792 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
1793 SafePointNode* map = this->map();
1794 Node* region = map->control();
1795 assert(region->is_Region(), "");
1797 Node* o = map->in(idx);
1798 assert(o != NULL, "");
1800 if (o == top()) return NULL; // TOP always merges into TOP
1802 if (o->is_Phi() && o->as_Phi()->region() == region) {
1803 return o->as_Phi();
1804 }
1806 // Now use a Phi here for merging
1807 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1808 const JVMState* jvms = map->jvms();
1809 const Type* t;
1810 if (jvms->is_loc(idx)) {
1811 t = block()->local_type_at(idx - jvms->locoff());
1812 } else if (jvms->is_stk(idx)) {
1813 t = block()->stack_type_at(idx - jvms->stkoff());
1814 } else if (jvms->is_mon(idx)) {
1815 assert(!jvms->is_monitor_box(idx), "no phis for boxes");
1816 t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
1817 } else if ((uint)idx < TypeFunc::Parms) {
1818 t = o->bottom_type(); // Type::RETURN_ADDRESS or such-like.
1819 } else {
1820 assert(false, "no type information for this phi");
1821 }
1823 // If the type falls to bottom, then this must be a local that
1824 // is mixing ints and oops or some such. Forcing it to top
1825 // makes it go dead.
1826 if (t == Type::BOTTOM) {
1827 map->set_req(idx, top());
1828 return NULL;
1829 }
1831 // Do not create phis for top either.
1832 // A top on a non-null control flow must be an unused even after the.phi.
1833 if (t == Type::TOP || t == Type::HALF) {
1834 map->set_req(idx, top());
1835 return NULL;
1836 }
1838 PhiNode* phi = PhiNode::make(region, o, t);
1839 gvn().set_type(phi, t);
1840 if (C->do_escape_analysis()) record_for_igvn(phi);
1841 map->set_req(idx, phi);
1842 return phi;
1843 }
1845 //--------------------------ensure_memory_phi----------------------------------
1846 // Turn the idx'th slice of the current memory into a Phi
1847 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
1848 MergeMemNode* mem = merged_memory();
1849 Node* region = control();
1850 assert(region->is_Region(), "");
1852 Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
1853 assert(o != NULL && o != top(), "");
1855 PhiNode* phi;
1856 if (o->is_Phi() && o->as_Phi()->region() == region) {
1857 phi = o->as_Phi();
1858 if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
1859 // clone the shared base memory phi to make a new memory split
1860 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1861 const Type* t = phi->bottom_type();
1862 const TypePtr* adr_type = C->get_adr_type(idx);
1863 phi = phi->slice_memory(adr_type);
1864 gvn().set_type(phi, t);
1865 }
1866 return phi;
1867 }
1869 // Now use a Phi here for merging
1870 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1871 const Type* t = o->bottom_type();
1872 const TypePtr* adr_type = C->get_adr_type(idx);
1873 phi = PhiNode::make(region, o, t, adr_type);
1874 gvn().set_type(phi, t);
1875 if (idx == Compile::AliasIdxBot)
1876 mem->set_base_memory(phi);
1877 else
1878 mem->set_memory_at(idx, phi);
1879 return phi;
1880 }
1882 //------------------------------call_register_finalizer-----------------------
1883 // Check the klass of the receiver and call register_finalizer if the
1884 // class need finalization.
1885 void Parse::call_register_finalizer() {
1886 Node* receiver = local(0);
1887 assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
1888 "must have non-null instance type");
1890 const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
1891 if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
1892 // The type isn't known exactly so see if CHA tells us anything.
1893 ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
1894 if (!Dependencies::has_finalizable_subclass(ik)) {
1895 // No finalizable subclasses so skip the dynamic check.
1896 C->dependencies()->assert_has_no_finalizable_subclasses(ik);
1897 return;
1898 }
1899 }
1901 // Insert a dynamic test for whether the instance needs
1902 // finalization. In general this will fold up since the concrete
1903 // class is often visible so the access flags are constant.
1904 Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
1905 Node* klass = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), klass_addr, TypeInstPtr::KLASS) );
1907 Node* access_flags_addr = basic_plus_adr(klass, klass, Klass::access_flags_offset_in_bytes() + sizeof(oopDesc));
1908 Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT);
1910 Node* mask = _gvn.transform(new (C, 3) AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
1911 Node* check = _gvn.transform(new (C, 3) CmpINode(mask, intcon(0)));
1912 Node* test = _gvn.transform(new (C, 2) BoolNode(check, BoolTest::ne));
1914 IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
1916 RegionNode* result_rgn = new (C, 3) RegionNode(3);
1917 record_for_igvn(result_rgn);
1919 Node *skip_register = _gvn.transform(new (C, 1) IfFalseNode(iff));
1920 result_rgn->init_req(1, skip_register);
1922 Node *needs_register = _gvn.transform(new (C, 1) IfTrueNode(iff));
1923 set_control(needs_register);
1924 if (stopped()) {
1925 // There is no slow path.
1926 result_rgn->init_req(2, top());
1927 } else {
1928 Node *call = make_runtime_call(RC_NO_LEAF,
1929 OptoRuntime::register_finalizer_Type(),
1930 OptoRuntime::register_finalizer_Java(),
1931 NULL, TypePtr::BOTTOM,
1932 receiver);
1933 make_slow_call_ex(call, env()->Throwable_klass(), true);
1935 Node* fast_io = call->in(TypeFunc::I_O);
1936 Node* fast_mem = call->in(TypeFunc::Memory);
1937 // These two phis are pre-filled with copies of of the fast IO and Memory
1938 Node* io_phi = PhiNode::make(result_rgn, fast_io, Type::ABIO);
1939 Node* mem_phi = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
1941 result_rgn->init_req(2, control());
1942 io_phi ->init_req(2, i_o());
1943 mem_phi ->init_req(2, reset_memory());
1945 set_all_memory( _gvn.transform(mem_phi) );
1946 set_i_o( _gvn.transform(io_phi) );
1947 }
1949 set_control( _gvn.transform(result_rgn) );
1950 }
1952 //------------------------------return_current---------------------------------
1953 // Append current _map to _exit_return
1954 void Parse::return_current(Node* value) {
1955 if (RegisterFinalizersAtInit &&
1956 method()->intrinsic_id() == vmIntrinsics::_Object_init) {
1957 call_register_finalizer();
1958 }
1960 // Do not set_parse_bci, so that return goo is credited to the return insn.
1961 set_bci(InvocationEntryBci);
1962 if (method()->is_synchronized() && GenerateSynchronizationCode) {
1963 shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
1964 }
1965 if (C->env()->dtrace_method_probes()) {
1966 make_dtrace_method_exit(method());
1967 }
1968 SafePointNode* exit_return = _exits.map();
1969 exit_return->in( TypeFunc::Control )->add_req( control() );
1970 exit_return->in( TypeFunc::I_O )->add_req( i_o () );
1971 Node *mem = exit_return->in( TypeFunc::Memory );
1972 for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
1973 if (mms.is_empty()) {
1974 // get a copy of the base memory, and patch just this one input
1975 const TypePtr* adr_type = mms.adr_type(C);
1976 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
1977 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
1978 gvn().set_type_bottom(phi);
1979 phi->del_req(phi->req()-1); // prepare to re-patch
1980 mms.set_memory(phi);
1981 }
1982 mms.memory()->add_req(mms.memory2());
1983 }
1985 // frame pointer is always same, already captured
1986 if (value != NULL) {
1987 // If returning oops to an interface-return, there is a silent free
1988 // cast from oop to interface allowed by the Verifier. Make it explicit
1989 // here.
1990 Node* phi = _exits.argument(0);
1991 const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
1992 if( tr && tr->klass()->is_loaded() &&
1993 tr->klass()->is_interface() ) {
1994 const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
1995 if (tp && tp->klass()->is_loaded() &&
1996 !tp->klass()->is_interface()) {
1997 // sharpen the type eagerly; this eases certain assert checking
1998 if (tp->higher_equal(TypeInstPtr::NOTNULL))
1999 tr = tr->join(TypeInstPtr::NOTNULL)->is_instptr();
2000 value = _gvn.transform(new (C, 2) CheckCastPPNode(0,value,tr));
2001 }
2002 }
2003 phi->add_req(value);
2004 }
2006 stop_and_kill_map(); // This CFG path dies here
2007 }
2010 //------------------------------add_safepoint----------------------------------
2011 void Parse::add_safepoint() {
2012 // See if we can avoid this safepoint. No need for a SafePoint immediately
2013 // after a Call (except Leaf Call) or another SafePoint.
2014 Node *proj = control();
2015 bool add_poll_param = SafePointNode::needs_polling_address_input();
2016 uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2017 if( proj->is_Proj() ) {
2018 Node *n0 = proj->in(0);
2019 if( n0->is_Catch() ) {
2020 n0 = n0->in(0)->in(0);
2021 assert( n0->is_Call(), "expect a call here" );
2022 }
2023 if( n0->is_Call() ) {
2024 if( n0->as_Call()->guaranteed_safepoint() )
2025 return;
2026 } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2027 return;
2028 }
2029 }
2031 // Clear out dead values from the debug info.
2032 kill_dead_locals();
2034 // Clone the JVM State
2035 SafePointNode *sfpnt = new (C, parms) SafePointNode(parms, NULL);
2037 // Capture memory state BEFORE a SafePoint. Since we can block at a
2038 // SafePoint we need our GC state to be safe; i.e. we need all our current
2039 // write barriers (card marks) to not float down after the SafePoint so we
2040 // must read raw memory. Likewise we need all oop stores to match the card
2041 // marks. If deopt can happen, we need ALL stores (we need the correct JVM
2042 // state on a deopt).
2044 // We do not need to WRITE the memory state after a SafePoint. The control
2045 // edge will keep card-marks and oop-stores from floating up from below a
2046 // SafePoint and our true dependency added here will keep them from floating
2047 // down below a SafePoint.
2049 // Clone the current memory state
2050 Node* mem = MergeMemNode::make(C, map()->memory());
2052 mem = _gvn.transform(mem);
2054 // Pass control through the safepoint
2055 sfpnt->init_req(TypeFunc::Control , control());
2056 // Fix edges normally used by a call
2057 sfpnt->init_req(TypeFunc::I_O , top() );
2058 sfpnt->init_req(TypeFunc::Memory , mem );
2059 sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2060 sfpnt->init_req(TypeFunc::FramePtr , top() );
2062 // Create a node for the polling address
2063 if( add_poll_param ) {
2064 Node *polladr = ConPNode::make(C, (address)os::get_polling_page());
2065 sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2066 }
2068 // Fix up the JVM State edges
2069 add_safepoint_edges(sfpnt);
2070 Node *transformed_sfpnt = _gvn.transform(sfpnt);
2071 set_control(transformed_sfpnt);
2073 // Provide an edge from root to safepoint. This makes the safepoint
2074 // appear useful until the parse has completed.
2075 if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2076 assert(C->root() != NULL, "Expect parse is still valid");
2077 C->root()->add_prec(transformed_sfpnt);
2078 }
2079 }
2081 #ifndef PRODUCT
2082 //------------------------show_parse_info--------------------------------------
2083 void Parse::show_parse_info() {
2084 InlineTree* ilt = NULL;
2085 if (C->ilt() != NULL) {
2086 JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2087 ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2088 }
2089 if (PrintCompilation && Verbose) {
2090 if (depth() == 1) {
2091 if( ilt->count_inlines() ) {
2092 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2093 ilt->count_inline_bcs());
2094 tty->cr();
2095 }
2096 } else {
2097 if (method()->is_synchronized()) tty->print("s");
2098 if (method()->has_exception_handlers()) tty->print("!");
2099 // Check this is not the final compiled version
2100 if (C->trap_can_recompile()) {
2101 tty->print("-");
2102 } else {
2103 tty->print(" ");
2104 }
2105 method()->print_short_name();
2106 if (is_osr_parse()) {
2107 tty->print(" @ %d", osr_bci());
2108 }
2109 tty->print(" (%d bytes)",method()->code_size());
2110 if (ilt->count_inlines()) {
2111 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2112 ilt->count_inline_bcs());
2113 }
2114 tty->cr();
2115 }
2116 }
2117 if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2118 // Print that we succeeded; suppress this message on the first osr parse.
2120 if (method()->is_synchronized()) tty->print("s");
2121 if (method()->has_exception_handlers()) tty->print("!");
2122 // Check this is not the final compiled version
2123 if (C->trap_can_recompile() && depth() == 1) {
2124 tty->print("-");
2125 } else {
2126 tty->print(" ");
2127 }
2128 if( depth() != 1 ) { tty->print(" "); } // missing compile count
2129 for (int i = 1; i < depth(); ++i) { tty->print(" "); }
2130 method()->print_short_name();
2131 if (is_osr_parse()) {
2132 tty->print(" @ %d", osr_bci());
2133 }
2134 if (ilt->caller_bci() != -1) {
2135 tty->print(" @ %d", ilt->caller_bci());
2136 }
2137 tty->print(" (%d bytes)",method()->code_size());
2138 if (ilt->count_inlines()) {
2139 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2140 ilt->count_inline_bcs());
2141 }
2142 tty->cr();
2143 }
2144 }
2147 //------------------------------dump-------------------------------------------
2148 // Dump information associated with the bytecodes of current _method
2149 void Parse::dump() {
2150 if( method() != NULL ) {
2151 // Iterate over bytecodes
2152 ciBytecodeStream iter(method());
2153 for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2154 dump_bci( iter.cur_bci() );
2155 tty->cr();
2156 }
2157 }
2158 }
2160 // Dump information associated with a byte code index, 'bci'
2161 void Parse::dump_bci(int bci) {
2162 // Output info on merge-points, cloning, and within _jsr..._ret
2163 // NYI
2164 tty->print(" bci:%d", bci);
2165 }
2167 #endif