Tue, 05 Nov 2013 01:57:18 -0800
8017065: C2 allows safepoint checks to leak into G1 pre-barriers
Summary: Make all raw loads strictly respect control dependencies, make sure RCE doesn't move raw loads, add verification of G1 pre-barriers.
Reviewed-by: kvn, roland
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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23 */
25 #include "precompiled.hpp"
26 #include "compiler/compileLog.hpp"
27 #include "interpreter/linkResolver.hpp"
28 #include "oops/method.hpp"
29 #include "opto/addnode.hpp"
30 #include "opto/idealGraphPrinter.hpp"
31 #include "opto/locknode.hpp"
32 #include "opto/memnode.hpp"
33 #include "opto/parse.hpp"
34 #include "opto/rootnode.hpp"
35 #include "opto/runtime.hpp"
36 #include "runtime/arguments.hpp"
37 #include "runtime/handles.inline.hpp"
38 #include "runtime/sharedRuntime.hpp"
39 #include "utilities/copy.hpp"
41 // Static array so we can figure out which bytecodes stop us from compiling
42 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
43 // and eventually should be encapsulated in a proper class (gri 8/18/98).
45 int nodes_created = 0;
46 int methods_parsed = 0;
47 int methods_seen = 0;
48 int blocks_parsed = 0;
49 int blocks_seen = 0;
51 int explicit_null_checks_inserted = 0;
52 int explicit_null_checks_elided = 0;
53 int all_null_checks_found = 0, implicit_null_checks = 0;
54 int implicit_null_throws = 0;
56 int reclaim_idx = 0;
57 int reclaim_in = 0;
58 int reclaim_node = 0;
60 #ifndef PRODUCT
61 bool Parse::BytecodeParseHistogram::_initialized = false;
62 uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
63 uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
64 uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
65 uint Parse::BytecodeParseHistogram::_new_values [Bytecodes::number_of_codes];
66 #endif
68 //------------------------------print_statistics-------------------------------
69 #ifndef PRODUCT
70 void Parse::print_statistics() {
71 tty->print_cr("--- Compiler Statistics ---");
72 tty->print("Methods seen: %d Methods parsed: %d", methods_seen, methods_parsed);
73 tty->print(" Nodes created: %d", nodes_created);
74 tty->cr();
75 if (methods_seen != methods_parsed)
76 tty->print_cr("Reasons for parse failures (NOT cumulative):");
77 tty->print_cr("Blocks parsed: %d Blocks seen: %d", blocks_parsed, blocks_seen);
79 if( explicit_null_checks_inserted )
80 tty->print_cr("%d original NULL checks - %d elided (%2d%%); optimizer leaves %d,", explicit_null_checks_inserted, explicit_null_checks_elided, (100*explicit_null_checks_elided)/explicit_null_checks_inserted, all_null_checks_found);
81 if( all_null_checks_found )
82 tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
83 (100*implicit_null_checks)/all_null_checks_found);
84 if( implicit_null_throws )
85 tty->print_cr("%d implicit null exceptions at runtime",
86 implicit_null_throws);
88 if( PrintParseStatistics && BytecodeParseHistogram::initialized() ) {
89 BytecodeParseHistogram::print();
90 }
91 }
92 #endif
94 //------------------------------ON STACK REPLACEMENT---------------------------
96 // Construct a node which can be used to get incoming state for
97 // on stack replacement.
98 Node *Parse::fetch_interpreter_state(int index,
99 BasicType bt,
100 Node *local_addrs,
101 Node *local_addrs_base) {
102 Node *mem = memory(Compile::AliasIdxRaw);
103 Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
104 Node *ctl = control();
106 // Very similar to LoadNode::make, except we handle un-aligned longs and
107 // doubles on Sparc. Intel can handle them just fine directly.
108 Node *l;
109 switch( bt ) { // Signature is flattened
110 case T_INT: l = new (C) LoadINode( ctl, mem, adr, TypeRawPtr::BOTTOM ); break;
111 case T_FLOAT: l = new (C) LoadFNode( ctl, mem, adr, TypeRawPtr::BOTTOM ); break;
112 case T_ADDRESS: l = new (C) LoadPNode( ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM ); break;
113 case T_OBJECT: l = new (C) LoadPNode( ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM ); break;
114 case T_LONG:
115 case T_DOUBLE: {
116 // Since arguments are in reverse order, the argument address 'adr'
117 // refers to the back half of the long/double. Recompute adr.
118 adr = basic_plus_adr( local_addrs_base, local_addrs, -(index+1)*wordSize );
119 if( Matcher::misaligned_doubles_ok ) {
120 l = (bt == T_DOUBLE)
121 ? (Node*)new (C) LoadDNode( ctl, mem, adr, TypeRawPtr::BOTTOM )
122 : (Node*)new (C) LoadLNode( ctl, mem, adr, TypeRawPtr::BOTTOM );
123 } else {
124 l = (bt == T_DOUBLE)
125 ? (Node*)new (C) LoadD_unalignedNode( ctl, mem, adr, TypeRawPtr::BOTTOM )
126 : (Node*)new (C) LoadL_unalignedNode( ctl, mem, adr, TypeRawPtr::BOTTOM );
127 }
128 break;
129 }
130 default: ShouldNotReachHere();
131 }
132 return _gvn.transform(l);
133 }
135 // Helper routine to prevent the interpreter from handing
136 // unexpected typestate to an OSR method.
137 // The Node l is a value newly dug out of the interpreter frame.
138 // The type is the type predicted by ciTypeFlow. Note that it is
139 // not a general type, but can only come from Type::get_typeflow_type.
140 // The safepoint is a map which will feed an uncommon trap.
141 Node* Parse::check_interpreter_type(Node* l, const Type* type,
142 SafePointNode* &bad_type_exit) {
144 const TypeOopPtr* tp = type->isa_oopptr();
146 // TypeFlow may assert null-ness if a type appears unloaded.
147 if (type == TypePtr::NULL_PTR ||
148 (tp != NULL && !tp->klass()->is_loaded())) {
149 // Value must be null, not a real oop.
150 Node* chk = _gvn.transform( new (C) CmpPNode(l, null()) );
151 Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
152 IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
153 set_control(_gvn.transform( new (C) IfTrueNode(iff) ));
154 Node* bad_type = _gvn.transform( new (C) IfFalseNode(iff) );
155 bad_type_exit->control()->add_req(bad_type);
156 l = null();
157 }
159 // Typeflow can also cut off paths from the CFG, based on
160 // types which appear unloaded, or call sites which appear unlinked.
161 // When paths are cut off, values at later merge points can rise
162 // toward more specific classes. Make sure these specific classes
163 // are still in effect.
164 if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
165 // TypeFlow asserted a specific object type. Value must have that type.
166 Node* bad_type_ctrl = NULL;
167 l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
168 bad_type_exit->control()->add_req(bad_type_ctrl);
169 }
171 BasicType bt_l = _gvn.type(l)->basic_type();
172 BasicType bt_t = type->basic_type();
173 assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
174 return l;
175 }
177 // Helper routine which sets up elements of the initial parser map when
178 // performing a parse for on stack replacement. Add values into map.
179 // The only parameter contains the address of a interpreter arguments.
180 void Parse::load_interpreter_state(Node* osr_buf) {
181 int index;
182 int max_locals = jvms()->loc_size();
183 int max_stack = jvms()->stk_size();
186 // Mismatch between method and jvms can occur since map briefly held
187 // an OSR entry state (which takes up one RawPtr word).
188 assert(max_locals == method()->max_locals(), "sanity");
189 assert(max_stack >= method()->max_stack(), "sanity");
190 assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
191 assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
193 // Find the start block.
194 Block* osr_block = start_block();
195 assert(osr_block->start() == osr_bci(), "sanity");
197 // Set initial BCI.
198 set_parse_bci(osr_block->start());
200 // Set initial stack depth.
201 set_sp(osr_block->start_sp());
203 // Check bailouts. We currently do not perform on stack replacement
204 // of loops in catch blocks or loops which branch with a non-empty stack.
205 if (sp() != 0) {
206 C->record_method_not_compilable("OSR starts with non-empty stack");
207 return;
208 }
209 // Do not OSR inside finally clauses:
210 if (osr_block->has_trap_at(osr_block->start())) {
211 C->record_method_not_compilable("OSR starts with an immediate trap");
212 return;
213 }
215 // Commute monitors from interpreter frame to compiler frame.
216 assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
217 int mcnt = osr_block->flow()->monitor_count();
218 Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
219 for (index = 0; index < mcnt; index++) {
220 // Make a BoxLockNode for the monitor.
221 Node *box = _gvn.transform(new (C) BoxLockNode(next_monitor()));
224 // Displaced headers and locked objects are interleaved in the
225 // temp OSR buffer. We only copy the locked objects out here.
226 // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
227 Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
228 // Try and copy the displaced header to the BoxNode
229 Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);
232 store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw);
234 // Build a bogus FastLockNode (no code will be generated) and push the
235 // monitor into our debug info.
236 const FastLockNode *flock = _gvn.transform(new (C) FastLockNode( 0, lock_object, box ))->as_FastLock();
237 map()->push_monitor(flock);
239 // If the lock is our method synchronization lock, tuck it away in
240 // _sync_lock for return and rethrow exit paths.
241 if (index == 0 && method()->is_synchronized()) {
242 _synch_lock = flock;
243 }
244 }
246 // Use the raw liveness computation to make sure that unexpected
247 // values don't propagate into the OSR frame.
248 MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
249 if (!live_locals.is_valid()) {
250 // Degenerate or breakpointed method.
251 C->record_method_not_compilable("OSR in empty or breakpointed method");
252 return;
253 }
255 // Extract the needed locals from the interpreter frame.
256 Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);
258 // find all the locals that the interpreter thinks contain live oops
259 const BitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
260 for (index = 0; index < max_locals; index++) {
262 if (!live_locals.at(index)) {
263 continue;
264 }
266 const Type *type = osr_block->local_type_at(index);
268 if (type->isa_oopptr() != NULL) {
270 // 6403625: Verify that the interpreter oopMap thinks that the oop is live
271 // else we might load a stale oop if the MethodLiveness disagrees with the
272 // result of the interpreter. If the interpreter says it is dead we agree
273 // by making the value go to top.
274 //
276 if (!live_oops.at(index)) {
277 if (C->log() != NULL) {
278 C->log()->elem("OSR_mismatch local_index='%d'",index);
279 }
280 set_local(index, null());
281 // and ignore it for the loads
282 continue;
283 }
284 }
286 // Filter out TOP, HALF, and BOTTOM. (Cf. ensure_phi.)
287 if (type == Type::TOP || type == Type::HALF) {
288 continue;
289 }
290 // If the type falls to bottom, then this must be a local that
291 // is mixing ints and oops or some such. Forcing it to top
292 // makes it go dead.
293 if (type == Type::BOTTOM) {
294 continue;
295 }
296 // Construct code to access the appropriate local.
297 BasicType bt = type->basic_type();
298 if (type == TypePtr::NULL_PTR) {
299 // Ptr types are mixed together with T_ADDRESS but NULL is
300 // really for T_OBJECT types so correct it.
301 bt = T_OBJECT;
302 }
303 Node *value = fetch_interpreter_state(index, bt, locals_addr, osr_buf);
304 set_local(index, value);
305 }
307 // Extract the needed stack entries from the interpreter frame.
308 for (index = 0; index < sp(); index++) {
309 const Type *type = osr_block->stack_type_at(index);
310 if (type != Type::TOP) {
311 // Currently the compiler bails out when attempting to on stack replace
312 // at a bci with a non-empty stack. We should not reach here.
313 ShouldNotReachHere();
314 }
315 }
317 // End the OSR migration
318 make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
319 CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
320 "OSR_migration_end", TypeRawPtr::BOTTOM,
321 osr_buf);
323 // Now that the interpreter state is loaded, make sure it will match
324 // at execution time what the compiler is expecting now:
325 SafePointNode* bad_type_exit = clone_map();
326 bad_type_exit->set_control(new (C) RegionNode(1));
328 assert(osr_block->flow()->jsrs()->size() == 0, "should be no jsrs live at osr point");
329 for (index = 0; index < max_locals; index++) {
330 if (stopped()) break;
331 Node* l = local(index);
332 if (l->is_top()) continue; // nothing here
333 const Type *type = osr_block->local_type_at(index);
334 if (type->isa_oopptr() != NULL) {
335 if (!live_oops.at(index)) {
336 // skip type check for dead oops
337 continue;
338 }
339 }
340 if (osr_block->flow()->local_type_at(index)->is_return_address()) {
341 // In our current system it's illegal for jsr addresses to be
342 // live into an OSR entry point because the compiler performs
343 // inlining of jsrs. ciTypeFlow has a bailout that detect this
344 // case and aborts the compile if addresses are live into an OSR
345 // entry point. Because of that we can assume that any address
346 // locals at the OSR entry point are dead. Method liveness
347 // isn't precise enought to figure out that they are dead in all
348 // cases so simply skip checking address locals all
349 // together. Any type check is guaranteed to fail since the
350 // interpreter type is the result of a load which might have any
351 // value and the expected type is a constant.
352 continue;
353 }
354 set_local(index, check_interpreter_type(l, type, bad_type_exit));
355 }
357 for (index = 0; index < sp(); index++) {
358 if (stopped()) break;
359 Node* l = stack(index);
360 if (l->is_top()) continue; // nothing here
361 const Type *type = osr_block->stack_type_at(index);
362 set_stack(index, check_interpreter_type(l, type, bad_type_exit));
363 }
365 if (bad_type_exit->control()->req() > 1) {
366 // Build an uncommon trap here, if any inputs can be unexpected.
367 bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
368 record_for_igvn(bad_type_exit->control());
369 SafePointNode* types_are_good = map();
370 set_map(bad_type_exit);
371 // The unexpected type happens because a new edge is active
372 // in the CFG, which typeflow had previously ignored.
373 // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
374 // This x will be typed as Integer if notReached is not yet linked.
375 // It could also happen due to a problem in ciTypeFlow analysis.
376 uncommon_trap(Deoptimization::Reason_constraint,
377 Deoptimization::Action_reinterpret);
378 set_map(types_are_good);
379 }
380 }
382 //------------------------------Parse------------------------------------------
383 // Main parser constructor.
384 Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses, Parse* parent)
385 : _exits(caller), _parent(parent)
386 {
387 // Init some variables
388 _caller = caller;
389 _method = parse_method;
390 _expected_uses = expected_uses;
391 _depth = 1 + (caller->has_method() ? caller->depth() : 0);
392 _wrote_final = false;
393 _alloc_with_final = NULL;
394 _entry_bci = InvocationEntryBci;
395 _tf = NULL;
396 _block = NULL;
397 debug_only(_block_count = -1);
398 debug_only(_blocks = (Block*)-1);
399 #ifndef PRODUCT
400 if (PrintCompilation || PrintOpto) {
401 // Make sure I have an inline tree, so I can print messages about it.
402 JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
403 InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method);
404 }
405 _max_switch_depth = 0;
406 _est_switch_depth = 0;
407 #endif
409 _tf = TypeFunc::make(method());
410 _iter.reset_to_method(method());
411 _flow = method()->get_flow_analysis();
412 if (_flow->failing()) {
413 C->record_method_not_compilable_all_tiers(_flow->failure_reason());
414 }
416 #ifndef PRODUCT
417 if (_flow->has_irreducible_entry()) {
418 C->set_parsed_irreducible_loop(true);
419 }
420 #endif
422 if (_expected_uses <= 0) {
423 _prof_factor = 1;
424 } else {
425 float prof_total = parse_method->interpreter_invocation_count();
426 if (prof_total <= _expected_uses) {
427 _prof_factor = 1;
428 } else {
429 _prof_factor = _expected_uses / prof_total;
430 }
431 }
433 CompileLog* log = C->log();
434 if (log != NULL) {
435 log->begin_head("parse method='%d' uses='%g'",
436 log->identify(parse_method), expected_uses);
437 if (depth() == 1 && C->is_osr_compilation()) {
438 log->print(" osr_bci='%d'", C->entry_bci());
439 }
440 log->stamp();
441 log->end_head();
442 }
444 // Accumulate deoptimization counts.
445 // (The range_check and store_check counts are checked elsewhere.)
446 ciMethodData* md = method()->method_data();
447 for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
448 uint md_count = md->trap_count(reason);
449 if (md_count != 0) {
450 if (md_count == md->trap_count_limit())
451 md_count += md->overflow_trap_count();
452 uint total_count = C->trap_count(reason);
453 uint old_count = total_count;
454 total_count += md_count;
455 // Saturate the add if it overflows.
456 if (total_count < old_count || total_count < md_count)
457 total_count = (uint)-1;
458 C->set_trap_count(reason, total_count);
459 if (log != NULL)
460 log->elem("observe trap='%s' count='%d' total='%d'",
461 Deoptimization::trap_reason_name(reason),
462 md_count, total_count);
463 }
464 }
465 // Accumulate total sum of decompilations, also.
466 C->set_decompile_count(C->decompile_count() + md->decompile_count());
468 _count_invocations = C->do_count_invocations();
469 _method_data_update = C->do_method_data_update();
471 if (log != NULL && method()->has_exception_handlers()) {
472 log->elem("observe that='has_exception_handlers'");
473 }
475 assert(method()->can_be_compiled(), "Can not parse this method, cutout earlier");
476 assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
478 // Always register dependence if JVMTI is enabled, because
479 // either breakpoint setting or hotswapping of methods may
480 // cause deoptimization.
481 if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
482 C->dependencies()->assert_evol_method(method());
483 }
485 methods_seen++;
487 // Do some special top-level things.
488 if (depth() == 1 && C->is_osr_compilation()) {
489 _entry_bci = C->entry_bci();
490 _flow = method()->get_osr_flow_analysis(osr_bci());
491 if (_flow->failing()) {
492 C->record_method_not_compilable(_flow->failure_reason());
493 #ifndef PRODUCT
494 if (PrintOpto && (Verbose || WizardMode)) {
495 tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
496 if (Verbose) {
497 method()->print();
498 method()->print_codes();
499 _flow->print();
500 }
501 }
502 #endif
503 }
504 _tf = C->tf(); // the OSR entry type is different
505 }
507 #ifdef ASSERT
508 if (depth() == 1) {
509 assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
510 if (C->tf() != tf()) {
511 MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
512 assert(C->env()->system_dictionary_modification_counter_changed(),
513 "Must invalidate if TypeFuncs differ");
514 }
515 } else {
516 assert(!this->is_osr_parse(), "no recursive OSR");
517 }
518 #endif
520 methods_parsed++;
521 #ifndef PRODUCT
522 // add method size here to guarantee that inlined methods are added too
523 if (TimeCompiler)
524 _total_bytes_compiled += method()->code_size();
526 show_parse_info();
527 #endif
529 if (failing()) {
530 if (log) log->done("parse");
531 return;
532 }
534 gvn().set_type(root(), root()->bottom_type());
535 gvn().transform(top());
537 // Import the results of the ciTypeFlow.
538 init_blocks();
540 // Merge point for all normal exits
541 build_exits();
543 // Setup the initial JVM state map.
544 SafePointNode* entry_map = create_entry_map();
546 // Check for bailouts during map initialization
547 if (failing() || entry_map == NULL) {
548 if (log) log->done("parse");
549 return;
550 }
552 Node_Notes* caller_nn = C->default_node_notes();
553 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
554 if (DebugInlinedCalls || depth() == 1) {
555 C->set_default_node_notes(make_node_notes(caller_nn));
556 }
558 if (is_osr_parse()) {
559 Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
560 entry_map->set_req(TypeFunc::Parms+0, top());
561 set_map(entry_map);
562 load_interpreter_state(osr_buf);
563 } else {
564 set_map(entry_map);
565 do_method_entry();
566 }
568 // Check for bailouts during method entry.
569 if (failing()) {
570 if (log) log->done("parse");
571 C->set_default_node_notes(caller_nn);
572 return;
573 }
575 entry_map = map(); // capture any changes performed by method setup code
576 assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
578 // We begin parsing as if we have just encountered a jump to the
579 // method entry.
580 Block* entry_block = start_block();
581 assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
582 set_map_clone(entry_map);
583 merge_common(entry_block, entry_block->next_path_num());
585 #ifndef PRODUCT
586 BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
587 set_parse_histogram( parse_histogram_obj );
588 #endif
590 // Parse all the basic blocks.
591 do_all_blocks();
593 C->set_default_node_notes(caller_nn);
595 // Check for bailouts during conversion to graph
596 if (failing()) {
597 if (log) log->done("parse");
598 return;
599 }
601 // Fix up all exiting control flow.
602 set_map(entry_map);
603 do_exits();
605 if (log) log->done("parse nodes='%d' live='%d' memory='%d'",
606 C->unique(), C->live_nodes(), C->node_arena()->used());
607 }
609 //---------------------------do_all_blocks-------------------------------------
610 void Parse::do_all_blocks() {
611 bool has_irreducible = flow()->has_irreducible_entry();
613 // Walk over all blocks in Reverse Post-Order.
614 while (true) {
615 bool progress = false;
616 for (int rpo = 0; rpo < block_count(); rpo++) {
617 Block* block = rpo_at(rpo);
619 if (block->is_parsed()) continue;
621 if (!block->is_merged()) {
622 // Dead block, no state reaches this block
623 continue;
624 }
626 // Prepare to parse this block.
627 load_state_from(block);
629 if (stopped()) {
630 // Block is dead.
631 continue;
632 }
634 blocks_parsed++;
636 progress = true;
637 if (block->is_loop_head() || block->is_handler() || has_irreducible && !block->is_ready()) {
638 // Not all preds have been parsed. We must build phis everywhere.
639 // (Note that dead locals do not get phis built, ever.)
640 ensure_phis_everywhere();
642 if (block->is_SEL_head() &&
643 (UseLoopPredicate || LoopLimitCheck)) {
644 // Add predicate to single entry (not irreducible) loop head.
645 assert(!block->has_merged_backedge(), "only entry paths should be merged for now");
646 // Need correct bci for predicate.
647 // It is fine to set it here since do_one_block() will set it anyway.
648 set_parse_bci(block->start());
649 add_predicate();
650 // Add new region for back branches.
651 int edges = block->pred_count() - block->preds_parsed() + 1; // +1 for original region
652 RegionNode *r = new (C) RegionNode(edges+1);
653 _gvn.set_type(r, Type::CONTROL);
654 record_for_igvn(r);
655 r->init_req(edges, control());
656 set_control(r);
657 // Add new phis.
658 ensure_phis_everywhere();
659 }
661 // Leave behind an undisturbed copy of the map, for future merges.
662 set_map(clone_map());
663 }
665 if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
666 // In the absence of irreducible loops, the Region and Phis
667 // associated with a merge that doesn't involve a backedge can
668 // be simplified now since the RPO parsing order guarantees
669 // that any path which was supposed to reach here has already
670 // been parsed or must be dead.
671 Node* c = control();
672 Node* result = _gvn.transform_no_reclaim(control());
673 if (c != result && TraceOptoParse) {
674 tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
675 }
676 if (result != top()) {
677 record_for_igvn(result);
678 }
679 }
681 // Parse the block.
682 do_one_block();
684 // Check for bailouts.
685 if (failing()) return;
686 }
688 // with irreducible loops multiple passes might be necessary to parse everything
689 if (!has_irreducible || !progress) {
690 break;
691 }
692 }
694 blocks_seen += block_count();
696 #ifndef PRODUCT
697 // Make sure there are no half-processed blocks remaining.
698 // Every remaining unprocessed block is dead and may be ignored now.
699 for (int rpo = 0; rpo < block_count(); rpo++) {
700 Block* block = rpo_at(rpo);
701 if (!block->is_parsed()) {
702 if (TraceOptoParse) {
703 tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
704 }
705 assert(!block->is_merged(), "no half-processed blocks");
706 }
707 }
708 #endif
709 }
711 //-------------------------------build_exits----------------------------------
712 // Build normal and exceptional exit merge points.
713 void Parse::build_exits() {
714 // make a clone of caller to prevent sharing of side-effects
715 _exits.set_map(_exits.clone_map());
716 _exits.clean_stack(_exits.sp());
717 _exits.sync_jvms();
719 RegionNode* region = new (C) RegionNode(1);
720 record_for_igvn(region);
721 gvn().set_type_bottom(region);
722 _exits.set_control(region);
724 // Note: iophi and memphi are not transformed until do_exits.
725 Node* iophi = new (C) PhiNode(region, Type::ABIO);
726 Node* memphi = new (C) PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
727 gvn().set_type_bottom(iophi);
728 gvn().set_type_bottom(memphi);
729 _exits.set_i_o(iophi);
730 _exits.set_all_memory(memphi);
732 // Add a return value to the exit state. (Do not push it yet.)
733 if (tf()->range()->cnt() > TypeFunc::Parms) {
734 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
735 // Don't "bind" an unloaded return klass to the ret_phi. If the klass
736 // becomes loaded during the subsequent parsing, the loaded and unloaded
737 // types will not join when we transform and push in do_exits().
738 const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
739 if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
740 ret_type = TypeOopPtr::BOTTOM;
741 }
742 int ret_size = type2size[ret_type->basic_type()];
743 Node* ret_phi = new (C) PhiNode(region, ret_type);
744 gvn().set_type_bottom(ret_phi);
745 _exits.ensure_stack(ret_size);
746 assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
747 assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
748 _exits.set_argument(0, ret_phi); // here is where the parser finds it
749 // Note: ret_phi is not yet pushed, until do_exits.
750 }
751 }
754 //----------------------------build_start_state-------------------------------
755 // Construct a state which contains only the incoming arguments from an
756 // unknown caller. The method & bci will be NULL & InvocationEntryBci.
757 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
758 int arg_size = tf->domain()->cnt();
759 int max_size = MAX2(arg_size, (int)tf->range()->cnt());
760 JVMState* jvms = new (this) JVMState(max_size - TypeFunc::Parms);
761 SafePointNode* map = new (this) SafePointNode(max_size, NULL);
762 record_for_igvn(map);
763 assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
764 Node_Notes* old_nn = default_node_notes();
765 if (old_nn != NULL && has_method()) {
766 Node_Notes* entry_nn = old_nn->clone(this);
767 JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
768 entry_jvms->set_offsets(0);
769 entry_jvms->set_bci(entry_bci());
770 entry_nn->set_jvms(entry_jvms);
771 set_default_node_notes(entry_nn);
772 }
773 uint i;
774 for (i = 0; i < (uint)arg_size; i++) {
775 Node* parm = initial_gvn()->transform(new (this) ParmNode(start, i));
776 map->init_req(i, parm);
777 // Record all these guys for later GVN.
778 record_for_igvn(parm);
779 }
780 for (; i < map->req(); i++) {
781 map->init_req(i, top());
782 }
783 assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
784 set_default_node_notes(old_nn);
785 map->set_jvms(jvms);
786 jvms->set_map(map);
787 return jvms;
788 }
790 //-----------------------------make_node_notes---------------------------------
791 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
792 if (caller_nn == NULL) return NULL;
793 Node_Notes* nn = caller_nn->clone(C);
794 JVMState* caller_jvms = nn->jvms();
795 JVMState* jvms = new (C) JVMState(method(), caller_jvms);
796 jvms->set_offsets(0);
797 jvms->set_bci(_entry_bci);
798 nn->set_jvms(jvms);
799 return nn;
800 }
803 //--------------------------return_values--------------------------------------
804 void Compile::return_values(JVMState* jvms) {
805 GraphKit kit(jvms);
806 Node* ret = new (this) ReturnNode(TypeFunc::Parms,
807 kit.control(),
808 kit.i_o(),
809 kit.reset_memory(),
810 kit.frameptr(),
811 kit.returnadr());
812 // Add zero or 1 return values
813 int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
814 if (ret_size > 0) {
815 kit.inc_sp(-ret_size); // pop the return value(s)
816 kit.sync_jvms();
817 ret->add_req(kit.argument(0));
818 // Note: The second dummy edge is not needed by a ReturnNode.
819 }
820 // bind it to root
821 root()->add_req(ret);
822 record_for_igvn(ret);
823 initial_gvn()->transform_no_reclaim(ret);
824 }
826 //------------------------rethrow_exceptions-----------------------------------
827 // Bind all exception states in the list into a single RethrowNode.
828 void Compile::rethrow_exceptions(JVMState* jvms) {
829 GraphKit kit(jvms);
830 if (!kit.has_exceptions()) return; // nothing to generate
831 // Load my combined exception state into the kit, with all phis transformed:
832 SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
833 Node* ex_oop = kit.use_exception_state(ex_map);
834 RethrowNode* exit = new (this) RethrowNode(kit.control(),
835 kit.i_o(), kit.reset_memory(),
836 kit.frameptr(), kit.returnadr(),
837 // like a return but with exception input
838 ex_oop);
839 // bind to root
840 root()->add_req(exit);
841 record_for_igvn(exit);
842 initial_gvn()->transform_no_reclaim(exit);
843 }
845 //---------------------------do_exceptions-------------------------------------
846 // Process exceptions arising from the current bytecode.
847 // Send caught exceptions to the proper handler within this method.
848 // Unhandled exceptions feed into _exit.
849 void Parse::do_exceptions() {
850 if (!has_exceptions()) return;
852 if (failing()) {
853 // Pop them all off and throw them away.
854 while (pop_exception_state() != NULL) ;
855 return;
856 }
858 PreserveJVMState pjvms(this, false);
860 SafePointNode* ex_map;
861 while ((ex_map = pop_exception_state()) != NULL) {
862 if (!method()->has_exception_handlers()) {
863 // Common case: Transfer control outward.
864 // Doing it this early allows the exceptions to common up
865 // even between adjacent method calls.
866 throw_to_exit(ex_map);
867 } else {
868 // Have to look at the exception first.
869 assert(stopped(), "catch_inline_exceptions trashes the map");
870 catch_inline_exceptions(ex_map);
871 stop_and_kill_map(); // we used up this exception state; kill it
872 }
873 }
875 // We now return to our regularly scheduled program:
876 }
878 //---------------------------throw_to_exit-------------------------------------
879 // Merge the given map into an exception exit from this method.
880 // The exception exit will handle any unlocking of receiver.
881 // The ex_oop must be saved within the ex_map, unlike merge_exception.
882 void Parse::throw_to_exit(SafePointNode* ex_map) {
883 // Pop the JVMS to (a copy of) the caller.
884 GraphKit caller;
885 caller.set_map_clone(_caller->map());
886 caller.set_bci(_caller->bci());
887 caller.set_sp(_caller->sp());
888 // Copy out the standard machine state:
889 for (uint i = 0; i < TypeFunc::Parms; i++) {
890 caller.map()->set_req(i, ex_map->in(i));
891 }
892 // ...and the exception:
893 Node* ex_oop = saved_ex_oop(ex_map);
894 SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
895 // Finally, collect the new exception state in my exits:
896 _exits.add_exception_state(caller_ex_map);
897 }
899 //------------------------------do_exits---------------------------------------
900 void Parse::do_exits() {
901 set_parse_bci(InvocationEntryBci);
903 // Now peephole on the return bits
904 Node* region = _exits.control();
905 _exits.set_control(gvn().transform(region));
907 Node* iophi = _exits.i_o();
908 _exits.set_i_o(gvn().transform(iophi));
910 if (wrote_final()) {
911 // This method (which must be a constructor by the rules of Java)
912 // wrote a final. The effects of all initializations must be
913 // committed to memory before any code after the constructor
914 // publishes the reference to the newly constructor object.
915 // Rather than wait for the publication, we simply block the
916 // writes here. Rather than put a barrier on only those writes
917 // which are required to complete, we force all writes to complete.
918 //
919 // "All bets are off" unless the first publication occurs after a
920 // normal return from the constructor. We do not attempt to detect
921 // such unusual early publications. But no barrier is needed on
922 // exceptional returns, since they cannot publish normally.
923 //
924 _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
925 #ifndef PRODUCT
926 if (PrintOpto && (Verbose || WizardMode)) {
927 method()->print_name();
928 tty->print_cr(" writes finals and needs a memory barrier");
929 }
930 #endif
931 }
933 for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
934 // transform each slice of the original memphi:
935 mms.set_memory(_gvn.transform(mms.memory()));
936 }
938 if (tf()->range()->cnt() > TypeFunc::Parms) {
939 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
940 Node* ret_phi = _gvn.transform( _exits.argument(0) );
941 assert(_exits.control()->is_top() || !_gvn.type(ret_phi)->empty(), "return value must be well defined");
942 _exits.push_node(ret_type->basic_type(), ret_phi);
943 }
945 // Note: Logic for creating and optimizing the ReturnNode is in Compile.
947 // Unlock along the exceptional paths.
948 // This is done late so that we can common up equivalent exceptions
949 // (e.g., null checks) arising from multiple points within this method.
950 // See GraphKit::add_exception_state, which performs the commoning.
951 bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
953 // record exit from a method if compiled while Dtrace is turned on.
954 if (do_synch || C->env()->dtrace_method_probes()) {
955 // First move the exception list out of _exits:
956 GraphKit kit(_exits.transfer_exceptions_into_jvms());
957 SafePointNode* normal_map = kit.map(); // keep this guy safe
958 // Now re-collect the exceptions into _exits:
959 SafePointNode* ex_map;
960 while ((ex_map = kit.pop_exception_state()) != NULL) {
961 Node* ex_oop = kit.use_exception_state(ex_map);
962 // Force the exiting JVM state to have this method at InvocationEntryBci.
963 // The exiting JVM state is otherwise a copy of the calling JVMS.
964 JVMState* caller = kit.jvms();
965 JVMState* ex_jvms = caller->clone_shallow(C);
966 ex_jvms->set_map(kit.clone_map());
967 ex_jvms->map()->set_jvms(ex_jvms);
968 ex_jvms->set_bci( InvocationEntryBci);
969 kit.set_jvms(ex_jvms);
970 if (do_synch) {
971 // Add on the synchronized-method box/object combo
972 kit.map()->push_monitor(_synch_lock);
973 // Unlock!
974 kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
975 }
976 if (C->env()->dtrace_method_probes()) {
977 kit.make_dtrace_method_exit(method());
978 }
979 // Done with exception-path processing.
980 ex_map = kit.make_exception_state(ex_oop);
981 assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
982 // Pop the last vestige of this method:
983 ex_map->set_jvms(caller->clone_shallow(C));
984 ex_map->jvms()->set_map(ex_map);
985 _exits.push_exception_state(ex_map);
986 }
987 assert(_exits.map() == normal_map, "keep the same return state");
988 }
990 {
991 // Capture very early exceptions (receiver null checks) from caller JVMS
992 GraphKit caller(_caller);
993 SafePointNode* ex_map;
994 while ((ex_map = caller.pop_exception_state()) != NULL) {
995 _exits.add_exception_state(ex_map);
996 }
997 }
998 }
1000 //-----------------------------create_entry_map-------------------------------
1001 // Initialize our parser map to contain the types at method entry.
1002 // For OSR, the map contains a single RawPtr parameter.
1003 // Initial monitor locking for sync. methods is performed by do_method_entry.
1004 SafePointNode* Parse::create_entry_map() {
1005 // Check for really stupid bail-out cases.
1006 uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1007 if (len >= 32760) {
1008 C->record_method_not_compilable_all_tiers("too many local variables");
1009 return NULL;
1010 }
1012 // If this is an inlined method, we may have to do a receiver null check.
1013 if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1014 GraphKit kit(_caller);
1015 kit.null_check_receiver_before_call(method());
1016 _caller = kit.transfer_exceptions_into_jvms();
1017 if (kit.stopped()) {
1018 _exits.add_exception_states_from(_caller);
1019 _exits.set_jvms(_caller);
1020 return NULL;
1021 }
1022 }
1024 assert(method() != NULL, "parser must have a method");
1026 // Create an initial safepoint to hold JVM state during parsing
1027 JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1028 set_map(new (C) SafePointNode(len, jvms));
1029 jvms->set_map(map());
1030 record_for_igvn(map());
1031 assert(jvms->endoff() == len, "correct jvms sizing");
1033 SafePointNode* inmap = _caller->map();
1034 assert(inmap != NULL, "must have inmap");
1036 uint i;
1038 // Pass thru the predefined input parameters.
1039 for (i = 0; i < TypeFunc::Parms; i++) {
1040 map()->init_req(i, inmap->in(i));
1041 }
1043 if (depth() == 1) {
1044 assert(map()->memory()->Opcode() == Op_Parm, "");
1045 // Insert the memory aliasing node
1046 set_all_memory(reset_memory());
1047 }
1048 assert(merged_memory(), "");
1050 // Now add the locals which are initially bound to arguments:
1051 uint arg_size = tf()->domain()->cnt();
1052 ensure_stack(arg_size - TypeFunc::Parms); // OSR methods have funny args
1053 for (i = TypeFunc::Parms; i < arg_size; i++) {
1054 map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1055 }
1057 // Clear out the rest of the map (locals and stack)
1058 for (i = arg_size; i < len; i++) {
1059 map()->init_req(i, top());
1060 }
1062 SafePointNode* entry_map = stop();
1063 return entry_map;
1064 }
1066 //-----------------------------do_method_entry--------------------------------
1067 // Emit any code needed in the pseudo-block before BCI zero.
1068 // The main thing to do is lock the receiver of a synchronized method.
1069 void Parse::do_method_entry() {
1070 set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1071 set_sp(0); // Java Stack Pointer
1073 NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1075 if (C->env()->dtrace_method_probes()) {
1076 make_dtrace_method_entry(method());
1077 }
1079 // If the method is synchronized, we need to construct a lock node, attach
1080 // it to the Start node, and pin it there.
1081 if (method()->is_synchronized()) {
1082 // Insert a FastLockNode right after the Start which takes as arguments
1083 // the current thread pointer, the "this" pointer & the address of the
1084 // stack slot pair used for the lock. The "this" pointer is a projection
1085 // off the start node, but the locking spot has to be constructed by
1086 // creating a ConLNode of 0, and boxing it with a BoxLockNode. The BoxLockNode
1087 // becomes the second argument to the FastLockNode call. The
1088 // FastLockNode becomes the new control parent to pin it to the start.
1090 // Setup Object Pointer
1091 Node *lock_obj = NULL;
1092 if(method()->is_static()) {
1093 ciInstance* mirror = _method->holder()->java_mirror();
1094 const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1095 lock_obj = makecon(t_lock);
1096 } else { // Else pass the "this" pointer,
1097 lock_obj = local(0); // which is Parm0 from StartNode
1098 }
1099 // Clear out dead values from the debug info.
1100 kill_dead_locals();
1101 // Build the FastLockNode
1102 _synch_lock = shared_lock(lock_obj);
1103 }
1105 // Feed profiling data for parameters to the type system so it can
1106 // propagate it as speculative types
1107 record_profiled_parameters_for_speculation();
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() || has_merged_backedge()), "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->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
1393 }
1395 if (block()->has_trap_at(bci())) {
1396 // We must respect the flow pass's traps, because it will refuse
1397 // to produce successors for trapping blocks.
1398 int trap_index = block()->flow()->trap_index();
1399 assert(trap_index != 0, "trap index must be valid");
1400 uncommon_trap(trap_index);
1401 break;
1402 }
1404 NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1406 #ifdef ASSERT
1407 int pre_bc_sp = sp();
1408 int inputs, depth;
1409 bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1410 assert(!have_se || pre_bc_sp >= inputs, err_msg_res("have enough stack to execute this BC: pre_bc_sp=%d, inputs=%d", pre_bc_sp, inputs));
1411 #endif //ASSERT
1413 do_one_bytecode();
1415 assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
1416 err_msg_res("incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth));
1418 do_exceptions();
1420 NOT_PRODUCT( parse_histogram()->record_change(); );
1422 if (log != NULL)
1423 log->clear_context(); // skip marker if nothing was printed
1425 // Fall into next bytecode. Each bytecode normally has 1 sequential
1426 // successor which is typically made ready by visiting this bytecode.
1427 // If the successor has several predecessors, then it is a merge
1428 // point, starts a new basic block, and is handled like other basic blocks.
1429 }
1430 }
1433 //------------------------------merge------------------------------------------
1434 void Parse::set_parse_bci(int bci) {
1435 set_bci(bci);
1436 Node_Notes* nn = C->default_node_notes();
1437 if (nn == NULL) return;
1439 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
1440 if (!DebugInlinedCalls && depth() > 1) {
1441 return;
1442 }
1444 // Update the JVMS annotation, if present.
1445 JVMState* jvms = nn->jvms();
1446 if (jvms != NULL && jvms->bci() != bci) {
1447 // Update the JVMS.
1448 jvms = jvms->clone_shallow(C);
1449 jvms->set_bci(bci);
1450 nn->set_jvms(jvms);
1451 }
1452 }
1454 //------------------------------merge------------------------------------------
1455 // Merge the current mapping into the basic block starting at bci
1456 void Parse::merge(int target_bci) {
1457 Block* target = successor_for_bci(target_bci);
1458 if (target == NULL) { handle_missing_successor(target_bci); return; }
1459 assert(!target->is_ready(), "our arrival must be expected");
1460 int pnum = target->next_path_num();
1461 merge_common(target, pnum);
1462 }
1464 //-------------------------merge_new_path--------------------------------------
1465 // Merge the current mapping into the basic block, using a new path
1466 void Parse::merge_new_path(int target_bci) {
1467 Block* target = successor_for_bci(target_bci);
1468 if (target == NULL) { handle_missing_successor(target_bci); return; }
1469 assert(!target->is_ready(), "new path into frozen graph");
1470 int pnum = target->add_new_path();
1471 merge_common(target, pnum);
1472 }
1474 //-------------------------merge_exception-------------------------------------
1475 // Merge the current mapping into the basic block starting at bci
1476 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
1477 void Parse::merge_exception(int target_bci) {
1478 assert(sp() == 1, "must have only the throw exception on the stack");
1479 Block* target = successor_for_bci(target_bci);
1480 if (target == NULL) { handle_missing_successor(target_bci); return; }
1481 assert(target->is_handler(), "exceptions are handled by special blocks");
1482 int pnum = target->add_new_path();
1483 merge_common(target, pnum);
1484 }
1486 //--------------------handle_missing_successor---------------------------------
1487 void Parse::handle_missing_successor(int target_bci) {
1488 #ifndef PRODUCT
1489 Block* b = block();
1490 int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1491 tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1492 #endif
1493 ShouldNotReachHere();
1494 }
1496 //--------------------------merge_common---------------------------------------
1497 void Parse::merge_common(Parse::Block* target, int pnum) {
1498 if (TraceOptoParse) {
1499 tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1500 }
1502 // Zap extra stack slots to top
1503 assert(sp() == target->start_sp(), "");
1504 clean_stack(sp());
1506 if (!target->is_merged()) { // No prior mapping at this bci
1507 if (TraceOptoParse) { tty->print(" with empty state"); }
1509 // If this path is dead, do not bother capturing it as a merge.
1510 // It is "as if" we had 1 fewer predecessors from the beginning.
1511 if (stopped()) {
1512 if (TraceOptoParse) tty->print_cr(", but path is dead and doesn't count");
1513 return;
1514 }
1516 // Record that a new block has been merged.
1517 ++_blocks_merged;
1519 // Make a region if we know there are multiple or unpredictable inputs.
1520 // (Also, if this is a plain fall-through, we might see another region,
1521 // which must not be allowed into this block's map.)
1522 if (pnum > PhiNode::Input // Known multiple inputs.
1523 || target->is_handler() // These have unpredictable inputs.
1524 || target->is_loop_head() // Known multiple inputs
1525 || control()->is_Region()) { // We must hide this guy.
1527 int current_bci = bci();
1528 set_parse_bci(target->start()); // Set target bci
1529 if (target->is_SEL_head()) {
1530 DEBUG_ONLY( target->mark_merged_backedge(block()); )
1531 if (target->start() == 0) {
1532 // Add loop predicate for the special case when
1533 // there are backbranches to the method entry.
1534 add_predicate();
1535 }
1536 }
1537 // Add a Region to start the new basic block. Phis will be added
1538 // later lazily.
1539 int edges = target->pred_count();
1540 if (edges < pnum) edges = pnum; // might be a new path!
1541 RegionNode *r = new (C) RegionNode(edges+1);
1542 gvn().set_type(r, Type::CONTROL);
1543 record_for_igvn(r);
1544 // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1545 // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1546 r->init_req(pnum, control());
1547 set_control(r);
1548 set_parse_bci(current_bci); // Restore bci
1549 }
1551 // Convert the existing Parser mapping into a mapping at this bci.
1552 store_state_to(target);
1553 assert(target->is_merged(), "do not come here twice");
1555 } else { // Prior mapping at this bci
1556 if (TraceOptoParse) { tty->print(" with previous state"); }
1557 #ifdef ASSERT
1558 if (target->is_SEL_head()) {
1559 target->mark_merged_backedge(block());
1560 }
1561 #endif
1562 // We must not manufacture more phis if the target is already parsed.
1563 bool nophi = target->is_parsed();
1565 SafePointNode* newin = map();// Hang on to incoming mapping
1566 Block* save_block = block(); // Hang on to incoming block;
1567 load_state_from(target); // Get prior mapping
1569 assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1570 assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1571 assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1572 assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1574 // Iterate over my current mapping and the old mapping.
1575 // Where different, insert Phi functions.
1576 // Use any existing Phi functions.
1577 assert(control()->is_Region(), "must be merging to a region");
1578 RegionNode* r = control()->as_Region();
1580 // Compute where to merge into
1581 // Merge incoming control path
1582 r->init_req(pnum, newin->control());
1584 if (pnum == 1) { // Last merge for this Region?
1585 if (!block()->flow()->is_irreducible_entry()) {
1586 Node* result = _gvn.transform_no_reclaim(r);
1587 if (r != result && TraceOptoParse) {
1588 tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1589 }
1590 }
1591 record_for_igvn(r);
1592 }
1594 // Update all the non-control inputs to map:
1595 assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1596 bool check_elide_phi = target->is_SEL_backedge(save_block);
1597 for (uint j = 1; j < newin->req(); j++) {
1598 Node* m = map()->in(j); // Current state of target.
1599 Node* n = newin->in(j); // Incoming change to target state.
1600 PhiNode* phi;
1601 if (m->is_Phi() && m->as_Phi()->region() == r)
1602 phi = m->as_Phi();
1603 else
1604 phi = NULL;
1605 if (m != n) { // Different; must merge
1606 switch (j) {
1607 // Frame pointer and Return Address never changes
1608 case TypeFunc::FramePtr:// Drop m, use the original value
1609 case TypeFunc::ReturnAdr:
1610 break;
1611 case TypeFunc::Memory: // Merge inputs to the MergeMem node
1612 assert(phi == NULL, "the merge contains phis, not vice versa");
1613 merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1614 continue;
1615 default: // All normal stuff
1616 if (phi == NULL) {
1617 const JVMState* jvms = map()->jvms();
1618 if (EliminateNestedLocks &&
1619 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1620 // BoxLock nodes are not commoning.
1621 // Use old BoxLock node as merged box.
1622 assert(newin->jvms()->is_monitor_box(j), "sanity");
1623 // This assert also tests that nodes are BoxLock.
1624 assert(BoxLockNode::same_slot(n, m), "sanity");
1625 C->gvn_replace_by(n, m);
1626 } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1627 phi = ensure_phi(j, nophi);
1628 }
1629 }
1630 break;
1631 }
1632 }
1633 // At this point, n might be top if:
1634 // - there is no phi (because TypeFlow detected a conflict), or
1635 // - the corresponding control edges is top (a dead incoming path)
1636 // It is a bug if we create a phi which sees a garbage value on a live path.
1638 if (phi != NULL) {
1639 assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1640 assert(phi->region() == r, "");
1641 phi->set_req(pnum, n); // Then add 'n' to the merge
1642 if (pnum == PhiNode::Input) {
1643 // Last merge for this Phi.
1644 // So far, Phis have had a reasonable type from ciTypeFlow.
1645 // Now _gvn will join that with the meet of current inputs.
1646 // BOTTOM is never permissible here, 'cause pessimistically
1647 // Phis of pointers cannot lose the basic pointer type.
1648 debug_only(const Type* bt1 = phi->bottom_type());
1649 assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1650 map()->set_req(j, _gvn.transform_no_reclaim(phi));
1651 debug_only(const Type* bt2 = phi->bottom_type());
1652 assert(bt2->higher_equal(bt1), "must be consistent with type-flow");
1653 record_for_igvn(phi);
1654 }
1655 }
1656 } // End of for all values to be merged
1658 if (pnum == PhiNode::Input &&
1659 !r->in(0)) { // The occasional useless Region
1660 assert(control() == r, "");
1661 set_control(r->nonnull_req());
1662 }
1664 // newin has been subsumed into the lazy merge, and is now dead.
1665 set_block(save_block);
1667 stop(); // done with this guy, for now
1668 }
1670 if (TraceOptoParse) {
1671 tty->print_cr(" on path %d", pnum);
1672 }
1674 // Done with this parser state.
1675 assert(stopped(), "");
1676 }
1679 //--------------------------merge_memory_edges---------------------------------
1680 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1681 // (nophi means we must not create phis, because we already parsed here)
1682 assert(n != NULL, "");
1683 // Merge the inputs to the MergeMems
1684 MergeMemNode* m = merged_memory();
1686 assert(control()->is_Region(), "must be merging to a region");
1687 RegionNode* r = control()->as_Region();
1689 PhiNode* base = NULL;
1690 MergeMemNode* remerge = NULL;
1691 for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1692 Node *p = mms.force_memory();
1693 Node *q = mms.memory2();
1694 if (mms.is_empty() && nophi) {
1695 // Trouble: No new splits allowed after a loop body is parsed.
1696 // Instead, wire the new split into a MergeMem on the backedge.
1697 // The optimizer will sort it out, slicing the phi.
1698 if (remerge == NULL) {
1699 assert(base != NULL, "");
1700 assert(base->in(0) != NULL, "should not be xformed away");
1701 remerge = MergeMemNode::make(C, base->in(pnum));
1702 gvn().set_type(remerge, Type::MEMORY);
1703 base->set_req(pnum, remerge);
1704 }
1705 remerge->set_memory_at(mms.alias_idx(), q);
1706 continue;
1707 }
1708 assert(!q->is_MergeMem(), "");
1709 PhiNode* phi;
1710 if (p != q) {
1711 phi = ensure_memory_phi(mms.alias_idx(), nophi);
1712 } else {
1713 if (p->is_Phi() && p->as_Phi()->region() == r)
1714 phi = p->as_Phi();
1715 else
1716 phi = NULL;
1717 }
1718 // Insert q into local phi
1719 if (phi != NULL) {
1720 assert(phi->region() == r, "");
1721 p = phi;
1722 phi->set_req(pnum, q);
1723 if (mms.at_base_memory()) {
1724 base = phi; // delay transforming it
1725 } else if (pnum == 1) {
1726 record_for_igvn(phi);
1727 p = _gvn.transform_no_reclaim(phi);
1728 }
1729 mms.set_memory(p);// store back through the iterator
1730 }
1731 }
1732 // Transform base last, in case we must fiddle with remerging.
1733 if (base != NULL && pnum == 1) {
1734 record_for_igvn(base);
1735 m->set_base_memory( _gvn.transform_no_reclaim(base) );
1736 }
1737 }
1740 //------------------------ensure_phis_everywhere-------------------------------
1741 void Parse::ensure_phis_everywhere() {
1742 ensure_phi(TypeFunc::I_O);
1744 // Ensure a phi on all currently known memories.
1745 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
1746 ensure_memory_phi(mms.alias_idx());
1747 debug_only(mms.set_memory()); // keep the iterator happy
1748 }
1750 // Note: This is our only chance to create phis for memory slices.
1751 // If we miss a slice that crops up later, it will have to be
1752 // merged into the base-memory phi that we are building here.
1753 // Later, the optimizer will comb out the knot, and build separate
1754 // phi-loops for each memory slice that matters.
1756 // Monitors must nest nicely and not get confused amongst themselves.
1757 // Phi-ify everything up to the monitors, though.
1758 uint monoff = map()->jvms()->monoff();
1759 uint nof_monitors = map()->jvms()->nof_monitors();
1761 assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
1762 bool check_elide_phi = block()->is_SEL_head();
1763 for (uint i = TypeFunc::Parms; i < monoff; i++) {
1764 if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
1765 ensure_phi(i);
1766 }
1767 }
1769 // Even monitors need Phis, though they are well-structured.
1770 // This is true for OSR methods, and also for the rare cases where
1771 // a monitor object is the subject of a replace_in_map operation.
1772 // See bugs 4426707 and 5043395.
1773 for (uint m = 0; m < nof_monitors; m++) {
1774 ensure_phi(map()->jvms()->monitor_obj_offset(m));
1775 }
1776 }
1779 //-----------------------------add_new_path------------------------------------
1780 // Add a previously unaccounted predecessor to this block.
1781 int Parse::Block::add_new_path() {
1782 // If there is no map, return the lowest unused path number.
1783 if (!is_merged()) return pred_count()+1; // there will be a map shortly
1785 SafePointNode* map = start_map();
1786 if (!map->control()->is_Region())
1787 return pred_count()+1; // there may be a region some day
1788 RegionNode* r = map->control()->as_Region();
1790 // Add new path to the region.
1791 uint pnum = r->req();
1792 r->add_req(NULL);
1794 for (uint i = 1; i < map->req(); i++) {
1795 Node* n = map->in(i);
1796 if (i == TypeFunc::Memory) {
1797 // Ensure a phi on all currently known memories.
1798 for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1799 Node* phi = mms.memory();
1800 if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1801 assert(phi->req() == pnum, "must be same size as region");
1802 phi->add_req(NULL);
1803 }
1804 }
1805 } else {
1806 if (n->is_Phi() && n->as_Phi()->region() == r) {
1807 assert(n->req() == pnum, "must be same size as region");
1808 n->add_req(NULL);
1809 }
1810 }
1811 }
1813 return pnum;
1814 }
1816 //------------------------------ensure_phi-------------------------------------
1817 // Turn the idx'th entry of the current map into a Phi
1818 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
1819 SafePointNode* map = this->map();
1820 Node* region = map->control();
1821 assert(region->is_Region(), "");
1823 Node* o = map->in(idx);
1824 assert(o != NULL, "");
1826 if (o == top()) return NULL; // TOP always merges into TOP
1828 if (o->is_Phi() && o->as_Phi()->region() == region) {
1829 return o->as_Phi();
1830 }
1832 // Now use a Phi here for merging
1833 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1834 const JVMState* jvms = map->jvms();
1835 const Type* t;
1836 if (jvms->is_loc(idx)) {
1837 t = block()->local_type_at(idx - jvms->locoff());
1838 } else if (jvms->is_stk(idx)) {
1839 t = block()->stack_type_at(idx - jvms->stkoff());
1840 } else if (jvms->is_mon(idx)) {
1841 assert(!jvms->is_monitor_box(idx), "no phis for boxes");
1842 t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
1843 } else if ((uint)idx < TypeFunc::Parms) {
1844 t = o->bottom_type(); // Type::RETURN_ADDRESS or such-like.
1845 } else {
1846 assert(false, "no type information for this phi");
1847 }
1849 // If the type falls to bottom, then this must be a local that
1850 // is mixing ints and oops or some such. Forcing it to top
1851 // makes it go dead.
1852 if (t == Type::BOTTOM) {
1853 map->set_req(idx, top());
1854 return NULL;
1855 }
1857 // Do not create phis for top either.
1858 // A top on a non-null control flow must be an unused even after the.phi.
1859 if (t == Type::TOP || t == Type::HALF) {
1860 map->set_req(idx, top());
1861 return NULL;
1862 }
1864 PhiNode* phi = PhiNode::make(region, o, t);
1865 gvn().set_type(phi, t);
1866 if (C->do_escape_analysis()) record_for_igvn(phi);
1867 map->set_req(idx, phi);
1868 return phi;
1869 }
1871 //--------------------------ensure_memory_phi----------------------------------
1872 // Turn the idx'th slice of the current memory into a Phi
1873 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
1874 MergeMemNode* mem = merged_memory();
1875 Node* region = control();
1876 assert(region->is_Region(), "");
1878 Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
1879 assert(o != NULL && o != top(), "");
1881 PhiNode* phi;
1882 if (o->is_Phi() && o->as_Phi()->region() == region) {
1883 phi = o->as_Phi();
1884 if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
1885 // clone the shared base memory phi to make a new memory split
1886 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1887 const Type* t = phi->bottom_type();
1888 const TypePtr* adr_type = C->get_adr_type(idx);
1889 phi = phi->slice_memory(adr_type);
1890 gvn().set_type(phi, t);
1891 }
1892 return phi;
1893 }
1895 // Now use a Phi here for merging
1896 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1897 const Type* t = o->bottom_type();
1898 const TypePtr* adr_type = C->get_adr_type(idx);
1899 phi = PhiNode::make(region, o, t, adr_type);
1900 gvn().set_type(phi, t);
1901 if (idx == Compile::AliasIdxBot)
1902 mem->set_base_memory(phi);
1903 else
1904 mem->set_memory_at(idx, phi);
1905 return phi;
1906 }
1908 //------------------------------call_register_finalizer-----------------------
1909 // Check the klass of the receiver and call register_finalizer if the
1910 // class need finalization.
1911 void Parse::call_register_finalizer() {
1912 Node* receiver = local(0);
1913 assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
1914 "must have non-null instance type");
1916 const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
1917 if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
1918 // The type isn't known exactly so see if CHA tells us anything.
1919 ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
1920 if (!Dependencies::has_finalizable_subclass(ik)) {
1921 // No finalizable subclasses so skip the dynamic check.
1922 C->dependencies()->assert_has_no_finalizable_subclasses(ik);
1923 return;
1924 }
1925 }
1927 // Insert a dynamic test for whether the instance needs
1928 // finalization. In general this will fold up since the concrete
1929 // class is often visible so the access flags are constant.
1930 Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
1931 Node* klass = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), klass_addr, TypeInstPtr::KLASS) );
1933 Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
1934 Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT);
1936 Node* mask = _gvn.transform(new (C) AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
1937 Node* check = _gvn.transform(new (C) CmpINode(mask, intcon(0)));
1938 Node* test = _gvn.transform(new (C) BoolNode(check, BoolTest::ne));
1940 IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
1942 RegionNode* result_rgn = new (C) RegionNode(3);
1943 record_for_igvn(result_rgn);
1945 Node *skip_register = _gvn.transform(new (C) IfFalseNode(iff));
1946 result_rgn->init_req(1, skip_register);
1948 Node *needs_register = _gvn.transform(new (C) IfTrueNode(iff));
1949 set_control(needs_register);
1950 if (stopped()) {
1951 // There is no slow path.
1952 result_rgn->init_req(2, top());
1953 } else {
1954 Node *call = make_runtime_call(RC_NO_LEAF,
1955 OptoRuntime::register_finalizer_Type(),
1956 OptoRuntime::register_finalizer_Java(),
1957 NULL, TypePtr::BOTTOM,
1958 receiver);
1959 make_slow_call_ex(call, env()->Throwable_klass(), true);
1961 Node* fast_io = call->in(TypeFunc::I_O);
1962 Node* fast_mem = call->in(TypeFunc::Memory);
1963 // These two phis are pre-filled with copies of of the fast IO and Memory
1964 Node* io_phi = PhiNode::make(result_rgn, fast_io, Type::ABIO);
1965 Node* mem_phi = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
1967 result_rgn->init_req(2, control());
1968 io_phi ->init_req(2, i_o());
1969 mem_phi ->init_req(2, reset_memory());
1971 set_all_memory( _gvn.transform(mem_phi) );
1972 set_i_o( _gvn.transform(io_phi) );
1973 }
1975 set_control( _gvn.transform(result_rgn) );
1976 }
1978 //------------------------------return_current---------------------------------
1979 // Append current _map to _exit_return
1980 void Parse::return_current(Node* value) {
1981 if (RegisterFinalizersAtInit &&
1982 method()->intrinsic_id() == vmIntrinsics::_Object_init) {
1983 call_register_finalizer();
1984 }
1986 // Do not set_parse_bci, so that return goo is credited to the return insn.
1987 set_bci(InvocationEntryBci);
1988 if (method()->is_synchronized() && GenerateSynchronizationCode) {
1989 shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
1990 }
1991 if (C->env()->dtrace_method_probes()) {
1992 make_dtrace_method_exit(method());
1993 }
1994 SafePointNode* exit_return = _exits.map();
1995 exit_return->in( TypeFunc::Control )->add_req( control() );
1996 exit_return->in( TypeFunc::I_O )->add_req( i_o () );
1997 Node *mem = exit_return->in( TypeFunc::Memory );
1998 for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
1999 if (mms.is_empty()) {
2000 // get a copy of the base memory, and patch just this one input
2001 const TypePtr* adr_type = mms.adr_type(C);
2002 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2003 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2004 gvn().set_type_bottom(phi);
2005 phi->del_req(phi->req()-1); // prepare to re-patch
2006 mms.set_memory(phi);
2007 }
2008 mms.memory()->add_req(mms.memory2());
2009 }
2011 // frame pointer is always same, already captured
2012 if (value != NULL) {
2013 // If returning oops to an interface-return, there is a silent free
2014 // cast from oop to interface allowed by the Verifier. Make it explicit
2015 // here.
2016 Node* phi = _exits.argument(0);
2017 const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
2018 if( tr && tr->klass()->is_loaded() &&
2019 tr->klass()->is_interface() ) {
2020 const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
2021 if (tp && tp->klass()->is_loaded() &&
2022 !tp->klass()->is_interface()) {
2023 // sharpen the type eagerly; this eases certain assert checking
2024 if (tp->higher_equal(TypeInstPtr::NOTNULL))
2025 tr = tr->join(TypeInstPtr::NOTNULL)->is_instptr();
2026 value = _gvn.transform(new (C) CheckCastPPNode(0,value,tr));
2027 }
2028 }
2029 phi->add_req(value);
2030 }
2032 stop_and_kill_map(); // This CFG path dies here
2033 }
2036 //------------------------------add_safepoint----------------------------------
2037 void Parse::add_safepoint() {
2038 // See if we can avoid this safepoint. No need for a SafePoint immediately
2039 // after a Call (except Leaf Call) or another SafePoint.
2040 Node *proj = control();
2041 bool add_poll_param = SafePointNode::needs_polling_address_input();
2042 uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2043 if( proj->is_Proj() ) {
2044 Node *n0 = proj->in(0);
2045 if( n0->is_Catch() ) {
2046 n0 = n0->in(0)->in(0);
2047 assert( n0->is_Call(), "expect a call here" );
2048 }
2049 if( n0->is_Call() ) {
2050 if( n0->as_Call()->guaranteed_safepoint() )
2051 return;
2052 } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2053 return;
2054 }
2055 }
2057 // Clear out dead values from the debug info.
2058 kill_dead_locals();
2060 // Clone the JVM State
2061 SafePointNode *sfpnt = new (C) SafePointNode(parms, NULL);
2063 // Capture memory state BEFORE a SafePoint. Since we can block at a
2064 // SafePoint we need our GC state to be safe; i.e. we need all our current
2065 // write barriers (card marks) to not float down after the SafePoint so we
2066 // must read raw memory. Likewise we need all oop stores to match the card
2067 // marks. If deopt can happen, we need ALL stores (we need the correct JVM
2068 // state on a deopt).
2070 // We do not need to WRITE the memory state after a SafePoint. The control
2071 // edge will keep card-marks and oop-stores from floating up from below a
2072 // SafePoint and our true dependency added here will keep them from floating
2073 // down below a SafePoint.
2075 // Clone the current memory state
2076 Node* mem = MergeMemNode::make(C, map()->memory());
2078 mem = _gvn.transform(mem);
2080 // Pass control through the safepoint
2081 sfpnt->init_req(TypeFunc::Control , control());
2082 // Fix edges normally used by a call
2083 sfpnt->init_req(TypeFunc::I_O , top() );
2084 sfpnt->init_req(TypeFunc::Memory , mem );
2085 sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2086 sfpnt->init_req(TypeFunc::FramePtr , top() );
2088 // Create a node for the polling address
2089 if( add_poll_param ) {
2090 Node *polladr = ConPNode::make(C, (address)os::get_polling_page());
2091 sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2092 }
2094 // Fix up the JVM State edges
2095 add_safepoint_edges(sfpnt);
2096 Node *transformed_sfpnt = _gvn.transform(sfpnt);
2097 set_control(transformed_sfpnt);
2099 // Provide an edge from root to safepoint. This makes the safepoint
2100 // appear useful until the parse has completed.
2101 if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2102 assert(C->root() != NULL, "Expect parse is still valid");
2103 C->root()->add_prec(transformed_sfpnt);
2104 }
2105 }
2107 #ifndef PRODUCT
2108 //------------------------show_parse_info--------------------------------------
2109 void Parse::show_parse_info() {
2110 InlineTree* ilt = NULL;
2111 if (C->ilt() != NULL) {
2112 JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2113 ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2114 }
2115 if (PrintCompilation && Verbose) {
2116 if (depth() == 1) {
2117 if( ilt->count_inlines() ) {
2118 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2119 ilt->count_inline_bcs());
2120 tty->cr();
2121 }
2122 } else {
2123 if (method()->is_synchronized()) tty->print("s");
2124 if (method()->has_exception_handlers()) tty->print("!");
2125 // Check this is not the final compiled version
2126 if (C->trap_can_recompile()) {
2127 tty->print("-");
2128 } else {
2129 tty->print(" ");
2130 }
2131 method()->print_short_name();
2132 if (is_osr_parse()) {
2133 tty->print(" @ %d", osr_bci());
2134 }
2135 tty->print(" (%d bytes)",method()->code_size());
2136 if (ilt->count_inlines()) {
2137 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2138 ilt->count_inline_bcs());
2139 }
2140 tty->cr();
2141 }
2142 }
2143 if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2144 // Print that we succeeded; suppress this message on the first osr parse.
2146 if (method()->is_synchronized()) tty->print("s");
2147 if (method()->has_exception_handlers()) tty->print("!");
2148 // Check this is not the final compiled version
2149 if (C->trap_can_recompile() && depth() == 1) {
2150 tty->print("-");
2151 } else {
2152 tty->print(" ");
2153 }
2154 if( depth() != 1 ) { tty->print(" "); } // missing compile count
2155 for (int i = 1; i < depth(); ++i) { tty->print(" "); }
2156 method()->print_short_name();
2157 if (is_osr_parse()) {
2158 tty->print(" @ %d", osr_bci());
2159 }
2160 if (ilt->caller_bci() != -1) {
2161 tty->print(" @ %d", ilt->caller_bci());
2162 }
2163 tty->print(" (%d bytes)",method()->code_size());
2164 if (ilt->count_inlines()) {
2165 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2166 ilt->count_inline_bcs());
2167 }
2168 tty->cr();
2169 }
2170 }
2173 //------------------------------dump-------------------------------------------
2174 // Dump information associated with the bytecodes of current _method
2175 void Parse::dump() {
2176 if( method() != NULL ) {
2177 // Iterate over bytecodes
2178 ciBytecodeStream iter(method());
2179 for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2180 dump_bci( iter.cur_bci() );
2181 tty->cr();
2182 }
2183 }
2184 }
2186 // Dump information associated with a byte code index, 'bci'
2187 void Parse::dump_bci(int bci) {
2188 // Output info on merge-points, cloning, and within _jsr..._ret
2189 // NYI
2190 tty->print(" bci:%d", bci);
2191 }
2193 #endif