Mon, 28 Jul 2014 15:06:38 -0700
8051344: JVM crashed in Compile::start() during method parsing w/ UseRTMDeopt turned on
Summary: call rtm_deopt() only if there were no compilation bailouts before.
Reviewed-by: kvn
1 /*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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, TypeInt::INT, MemNode::unordered); break;
111 case T_FLOAT: l = new (C) LoadFNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::FLOAT, MemNode::unordered); break;
112 case T_ADDRESS: l = new (C) LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, MemNode::unordered); break;
113 case T_OBJECT: l = new (C) LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM, MemNode::unordered); 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, Type::DOUBLE, MemNode::unordered)
122 : (Node*)new (C) LoadLNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeLong::LONG, MemNode::unordered);
123 } else {
124 l = (bt == T_DOUBLE)
125 ? (Node*)new (C) LoadD_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered)
126 : (Node*)new (C) LoadL_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered);
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, MemNode::unordered);
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 _wrote_volatile = false;
394 _alloc_with_final = NULL;
395 _entry_bci = InvocationEntryBci;
396 _tf = NULL;
397 _block = NULL;
398 debug_only(_block_count = -1);
399 debug_only(_blocks = (Block*)-1);
400 #ifndef PRODUCT
401 if (PrintCompilation || PrintOpto) {
402 // Make sure I have an inline tree, so I can print messages about it.
403 JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
404 InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method);
405 }
406 _max_switch_depth = 0;
407 _est_switch_depth = 0;
408 #endif
410 _tf = TypeFunc::make(method());
411 _iter.reset_to_method(method());
412 _flow = method()->get_flow_analysis();
413 if (_flow->failing()) {
414 C->record_method_not_compilable_all_tiers(_flow->failure_reason());
415 }
417 #ifndef PRODUCT
418 if (_flow->has_irreducible_entry()) {
419 C->set_parsed_irreducible_loop(true);
420 }
421 #endif
423 if (_expected_uses <= 0) {
424 _prof_factor = 1;
425 } else {
426 float prof_total = parse_method->interpreter_invocation_count();
427 if (prof_total <= _expected_uses) {
428 _prof_factor = 1;
429 } else {
430 _prof_factor = _expected_uses / prof_total;
431 }
432 }
434 CompileLog* log = C->log();
435 if (log != NULL) {
436 log->begin_head("parse method='%d' uses='%g'",
437 log->identify(parse_method), expected_uses);
438 if (depth() == 1 && C->is_osr_compilation()) {
439 log->print(" osr_bci='%d'", C->entry_bci());
440 }
441 log->stamp();
442 log->end_head();
443 }
445 // Accumulate deoptimization counts.
446 // (The range_check and store_check counts are checked elsewhere.)
447 ciMethodData* md = method()->method_data();
448 for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
449 uint md_count = md->trap_count(reason);
450 if (md_count != 0) {
451 if (md_count == md->trap_count_limit())
452 md_count += md->overflow_trap_count();
453 uint total_count = C->trap_count(reason);
454 uint old_count = total_count;
455 total_count += md_count;
456 // Saturate the add if it overflows.
457 if (total_count < old_count || total_count < md_count)
458 total_count = (uint)-1;
459 C->set_trap_count(reason, total_count);
460 if (log != NULL)
461 log->elem("observe trap='%s' count='%d' total='%d'",
462 Deoptimization::trap_reason_name(reason),
463 md_count, total_count);
464 }
465 }
466 // Accumulate total sum of decompilations, also.
467 C->set_decompile_count(C->decompile_count() + md->decompile_count());
469 _count_invocations = C->do_count_invocations();
470 _method_data_update = C->do_method_data_update();
472 if (log != NULL && method()->has_exception_handlers()) {
473 log->elem("observe that='has_exception_handlers'");
474 }
476 assert(method()->can_be_compiled(), "Can not parse this method, cutout earlier");
477 assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
479 // Always register dependence if JVMTI is enabled, because
480 // either breakpoint setting or hotswapping of methods may
481 // cause deoptimization.
482 if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
483 C->dependencies()->assert_evol_method(method());
484 }
486 methods_seen++;
488 // Do some special top-level things.
489 if (depth() == 1 && C->is_osr_compilation()) {
490 _entry_bci = C->entry_bci();
491 _flow = method()->get_osr_flow_analysis(osr_bci());
492 if (_flow->failing()) {
493 C->record_method_not_compilable(_flow->failure_reason());
494 #ifndef PRODUCT
495 if (PrintOpto && (Verbose || WizardMode)) {
496 tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
497 if (Verbose) {
498 method()->print();
499 method()->print_codes();
500 _flow->print();
501 }
502 }
503 #endif
504 }
505 _tf = C->tf(); // the OSR entry type is different
506 }
508 #ifdef ASSERT
509 if (depth() == 1) {
510 assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
511 if (C->tf() != tf()) {
512 MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
513 assert(C->env()->system_dictionary_modification_counter_changed(),
514 "Must invalidate if TypeFuncs differ");
515 }
516 } else {
517 assert(!this->is_osr_parse(), "no recursive OSR");
518 }
519 #endif
521 methods_parsed++;
522 #ifndef PRODUCT
523 // add method size here to guarantee that inlined methods are added too
524 if (TimeCompiler)
525 _total_bytes_compiled += method()->code_size();
527 show_parse_info();
528 #endif
530 if (failing()) {
531 if (log) log->done("parse");
532 return;
533 }
535 gvn().set_type(root(), root()->bottom_type());
536 gvn().transform(top());
538 // Import the results of the ciTypeFlow.
539 init_blocks();
541 // Merge point for all normal exits
542 build_exits();
544 // Setup the initial JVM state map.
545 SafePointNode* entry_map = create_entry_map();
547 // Check for bailouts during map initialization
548 if (failing() || entry_map == NULL) {
549 if (log) log->done("parse");
550 return;
551 }
553 Node_Notes* caller_nn = C->default_node_notes();
554 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
555 if (DebugInlinedCalls || depth() == 1) {
556 C->set_default_node_notes(make_node_notes(caller_nn));
557 }
559 if (is_osr_parse()) {
560 Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
561 entry_map->set_req(TypeFunc::Parms+0, top());
562 set_map(entry_map);
563 load_interpreter_state(osr_buf);
564 } else {
565 set_map(entry_map);
566 do_method_entry();
567 }
569 if (depth() == 1 && !failing()) {
570 // Add check to deoptimize the nmethod if RTM state was changed
571 rtm_deopt();
572 }
574 // Check for bailouts during method entry or RTM state check setup.
575 if (failing()) {
576 if (log) log->done("parse");
577 C->set_default_node_notes(caller_nn);
578 return;
579 }
581 entry_map = map(); // capture any changes performed by method setup code
582 assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
584 // We begin parsing as if we have just encountered a jump to the
585 // method entry.
586 Block* entry_block = start_block();
587 assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
588 set_map_clone(entry_map);
589 merge_common(entry_block, entry_block->next_path_num());
591 #ifndef PRODUCT
592 BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
593 set_parse_histogram( parse_histogram_obj );
594 #endif
596 // Parse all the basic blocks.
597 do_all_blocks();
599 C->set_default_node_notes(caller_nn);
601 // Check for bailouts during conversion to graph
602 if (failing()) {
603 if (log) log->done("parse");
604 return;
605 }
607 // Fix up all exiting control flow.
608 set_map(entry_map);
609 do_exits();
611 if (log) log->done("parse nodes='%d' live='%d' memory='" SIZE_FORMAT "'",
612 C->unique(), C->live_nodes(), C->node_arena()->used());
613 }
615 //---------------------------do_all_blocks-------------------------------------
616 void Parse::do_all_blocks() {
617 bool has_irreducible = flow()->has_irreducible_entry();
619 // Walk over all blocks in Reverse Post-Order.
620 while (true) {
621 bool progress = false;
622 for (int rpo = 0; rpo < block_count(); rpo++) {
623 Block* block = rpo_at(rpo);
625 if (block->is_parsed()) continue;
627 if (!block->is_merged()) {
628 // Dead block, no state reaches this block
629 continue;
630 }
632 // Prepare to parse this block.
633 load_state_from(block);
635 if (stopped()) {
636 // Block is dead.
637 continue;
638 }
640 blocks_parsed++;
642 progress = true;
643 if (block->is_loop_head() || block->is_handler() || has_irreducible && !block->is_ready()) {
644 // Not all preds have been parsed. We must build phis everywhere.
645 // (Note that dead locals do not get phis built, ever.)
646 ensure_phis_everywhere();
648 if (block->is_SEL_head() &&
649 (UseLoopPredicate || LoopLimitCheck)) {
650 // Add predicate to single entry (not irreducible) loop head.
651 assert(!block->has_merged_backedge(), "only entry paths should be merged for now");
652 // Need correct bci for predicate.
653 // It is fine to set it here since do_one_block() will set it anyway.
654 set_parse_bci(block->start());
655 add_predicate();
656 // Add new region for back branches.
657 int edges = block->pred_count() - block->preds_parsed() + 1; // +1 for original region
658 RegionNode *r = new (C) RegionNode(edges+1);
659 _gvn.set_type(r, Type::CONTROL);
660 record_for_igvn(r);
661 r->init_req(edges, control());
662 set_control(r);
663 // Add new phis.
664 ensure_phis_everywhere();
665 }
667 // Leave behind an undisturbed copy of the map, for future merges.
668 set_map(clone_map());
669 }
671 if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
672 // In the absence of irreducible loops, the Region and Phis
673 // associated with a merge that doesn't involve a backedge can
674 // be simplified now since the RPO parsing order guarantees
675 // that any path which was supposed to reach here has already
676 // been parsed or must be dead.
677 Node* c = control();
678 Node* result = _gvn.transform_no_reclaim(control());
679 if (c != result && TraceOptoParse) {
680 tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
681 }
682 if (result != top()) {
683 record_for_igvn(result);
684 }
685 }
687 // Parse the block.
688 do_one_block();
690 // Check for bailouts.
691 if (failing()) return;
692 }
694 // with irreducible loops multiple passes might be necessary to parse everything
695 if (!has_irreducible || !progress) {
696 break;
697 }
698 }
700 blocks_seen += block_count();
702 #ifndef PRODUCT
703 // Make sure there are no half-processed blocks remaining.
704 // Every remaining unprocessed block is dead and may be ignored now.
705 for (int rpo = 0; rpo < block_count(); rpo++) {
706 Block* block = rpo_at(rpo);
707 if (!block->is_parsed()) {
708 if (TraceOptoParse) {
709 tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
710 }
711 assert(!block->is_merged(), "no half-processed blocks");
712 }
713 }
714 #endif
715 }
717 //-------------------------------build_exits----------------------------------
718 // Build normal and exceptional exit merge points.
719 void Parse::build_exits() {
720 // make a clone of caller to prevent sharing of side-effects
721 _exits.set_map(_exits.clone_map());
722 _exits.clean_stack(_exits.sp());
723 _exits.sync_jvms();
725 RegionNode* region = new (C) RegionNode(1);
726 record_for_igvn(region);
727 gvn().set_type_bottom(region);
728 _exits.set_control(region);
730 // Note: iophi and memphi are not transformed until do_exits.
731 Node* iophi = new (C) PhiNode(region, Type::ABIO);
732 Node* memphi = new (C) PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
733 gvn().set_type_bottom(iophi);
734 gvn().set_type_bottom(memphi);
735 _exits.set_i_o(iophi);
736 _exits.set_all_memory(memphi);
738 // Add a return value to the exit state. (Do not push it yet.)
739 if (tf()->range()->cnt() > TypeFunc::Parms) {
740 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
741 // Don't "bind" an unloaded return klass to the ret_phi. If the klass
742 // becomes loaded during the subsequent parsing, the loaded and unloaded
743 // types will not join when we transform and push in do_exits().
744 const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
745 if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
746 ret_type = TypeOopPtr::BOTTOM;
747 }
748 int ret_size = type2size[ret_type->basic_type()];
749 Node* ret_phi = new (C) PhiNode(region, ret_type);
750 gvn().set_type_bottom(ret_phi);
751 _exits.ensure_stack(ret_size);
752 assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
753 assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
754 _exits.set_argument(0, ret_phi); // here is where the parser finds it
755 // Note: ret_phi is not yet pushed, until do_exits.
756 }
757 }
760 //----------------------------build_start_state-------------------------------
761 // Construct a state which contains only the incoming arguments from an
762 // unknown caller. The method & bci will be NULL & InvocationEntryBci.
763 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
764 int arg_size = tf->domain()->cnt();
765 int max_size = MAX2(arg_size, (int)tf->range()->cnt());
766 JVMState* jvms = new (this) JVMState(max_size - TypeFunc::Parms);
767 SafePointNode* map = new (this) SafePointNode(max_size, NULL);
768 record_for_igvn(map);
769 assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
770 Node_Notes* old_nn = default_node_notes();
771 if (old_nn != NULL && has_method()) {
772 Node_Notes* entry_nn = old_nn->clone(this);
773 JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
774 entry_jvms->set_offsets(0);
775 entry_jvms->set_bci(entry_bci());
776 entry_nn->set_jvms(entry_jvms);
777 set_default_node_notes(entry_nn);
778 }
779 uint i;
780 for (i = 0; i < (uint)arg_size; i++) {
781 Node* parm = initial_gvn()->transform(new (this) ParmNode(start, i));
782 map->init_req(i, parm);
783 // Record all these guys for later GVN.
784 record_for_igvn(parm);
785 }
786 for (; i < map->req(); i++) {
787 map->init_req(i, top());
788 }
789 assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
790 set_default_node_notes(old_nn);
791 map->set_jvms(jvms);
792 jvms->set_map(map);
793 return jvms;
794 }
796 //-----------------------------make_node_notes---------------------------------
797 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
798 if (caller_nn == NULL) return NULL;
799 Node_Notes* nn = caller_nn->clone(C);
800 JVMState* caller_jvms = nn->jvms();
801 JVMState* jvms = new (C) JVMState(method(), caller_jvms);
802 jvms->set_offsets(0);
803 jvms->set_bci(_entry_bci);
804 nn->set_jvms(jvms);
805 return nn;
806 }
809 //--------------------------return_values--------------------------------------
810 void Compile::return_values(JVMState* jvms) {
811 GraphKit kit(jvms);
812 Node* ret = new (this) ReturnNode(TypeFunc::Parms,
813 kit.control(),
814 kit.i_o(),
815 kit.reset_memory(),
816 kit.frameptr(),
817 kit.returnadr());
818 // Add zero or 1 return values
819 int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
820 if (ret_size > 0) {
821 kit.inc_sp(-ret_size); // pop the return value(s)
822 kit.sync_jvms();
823 ret->add_req(kit.argument(0));
824 // Note: The second dummy edge is not needed by a ReturnNode.
825 }
826 // bind it to root
827 root()->add_req(ret);
828 record_for_igvn(ret);
829 initial_gvn()->transform_no_reclaim(ret);
830 }
832 //------------------------rethrow_exceptions-----------------------------------
833 // Bind all exception states in the list into a single RethrowNode.
834 void Compile::rethrow_exceptions(JVMState* jvms) {
835 GraphKit kit(jvms);
836 if (!kit.has_exceptions()) return; // nothing to generate
837 // Load my combined exception state into the kit, with all phis transformed:
838 SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
839 Node* ex_oop = kit.use_exception_state(ex_map);
840 RethrowNode* exit = new (this) RethrowNode(kit.control(),
841 kit.i_o(), kit.reset_memory(),
842 kit.frameptr(), kit.returnadr(),
843 // like a return but with exception input
844 ex_oop);
845 // bind to root
846 root()->add_req(exit);
847 record_for_igvn(exit);
848 initial_gvn()->transform_no_reclaim(exit);
849 }
851 //---------------------------do_exceptions-------------------------------------
852 // Process exceptions arising from the current bytecode.
853 // Send caught exceptions to the proper handler within this method.
854 // Unhandled exceptions feed into _exit.
855 void Parse::do_exceptions() {
856 if (!has_exceptions()) return;
858 if (failing()) {
859 // Pop them all off and throw them away.
860 while (pop_exception_state() != NULL) ;
861 return;
862 }
864 PreserveJVMState pjvms(this, false);
866 SafePointNode* ex_map;
867 while ((ex_map = pop_exception_state()) != NULL) {
868 if (!method()->has_exception_handlers()) {
869 // Common case: Transfer control outward.
870 // Doing it this early allows the exceptions to common up
871 // even between adjacent method calls.
872 throw_to_exit(ex_map);
873 } else {
874 // Have to look at the exception first.
875 assert(stopped(), "catch_inline_exceptions trashes the map");
876 catch_inline_exceptions(ex_map);
877 stop_and_kill_map(); // we used up this exception state; kill it
878 }
879 }
881 // We now return to our regularly scheduled program:
882 }
884 //---------------------------throw_to_exit-------------------------------------
885 // Merge the given map into an exception exit from this method.
886 // The exception exit will handle any unlocking of receiver.
887 // The ex_oop must be saved within the ex_map, unlike merge_exception.
888 void Parse::throw_to_exit(SafePointNode* ex_map) {
889 // Pop the JVMS to (a copy of) the caller.
890 GraphKit caller;
891 caller.set_map_clone(_caller->map());
892 caller.set_bci(_caller->bci());
893 caller.set_sp(_caller->sp());
894 // Copy out the standard machine state:
895 for (uint i = 0; i < TypeFunc::Parms; i++) {
896 caller.map()->set_req(i, ex_map->in(i));
897 }
898 // ...and the exception:
899 Node* ex_oop = saved_ex_oop(ex_map);
900 SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
901 // Finally, collect the new exception state in my exits:
902 _exits.add_exception_state(caller_ex_map);
903 }
905 //------------------------------do_exits---------------------------------------
906 void Parse::do_exits() {
907 set_parse_bci(InvocationEntryBci);
909 // Now peephole on the return bits
910 Node* region = _exits.control();
911 _exits.set_control(gvn().transform(region));
913 Node* iophi = _exits.i_o();
914 _exits.set_i_o(gvn().transform(iophi));
916 // On PPC64, also add MemBarRelease for constructors which write
917 // volatile fields. As support_IRIW_for_not_multiple_copy_atomic_cpu
918 // is set on PPC64, no sync instruction is issued after volatile
919 // stores. We want to quarantee the same behaviour as on platforms
920 // with total store order, although this is not required by the Java
921 // memory model. So as with finals, we add a barrier here.
922 if (wrote_final() PPC64_ONLY(|| (wrote_volatile() && method()->is_initializer()))) {
923 // This method (which must be a constructor by the rules of Java)
924 // wrote a final. The effects of all initializations must be
925 // committed to memory before any code after the constructor
926 // publishes the reference to the newly constructor object.
927 // Rather than wait for the publication, we simply block the
928 // writes here. Rather than put a barrier on only those writes
929 // which are required to complete, we force all writes to complete.
930 //
931 // "All bets are off" unless the first publication occurs after a
932 // normal return from the constructor. We do not attempt to detect
933 // such unusual early publications. But no barrier is needed on
934 // exceptional returns, since they cannot publish normally.
935 //
936 _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
937 #ifndef PRODUCT
938 if (PrintOpto && (Verbose || WizardMode)) {
939 method()->print_name();
940 tty->print_cr(" writes finals and needs a memory barrier");
941 }
942 #endif
943 }
945 for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
946 // transform each slice of the original memphi:
947 mms.set_memory(_gvn.transform(mms.memory()));
948 }
950 if (tf()->range()->cnt() > TypeFunc::Parms) {
951 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
952 Node* ret_phi = _gvn.transform( _exits.argument(0) );
953 assert(_exits.control()->is_top() || !_gvn.type(ret_phi)->empty(), "return value must be well defined");
954 _exits.push_node(ret_type->basic_type(), ret_phi);
955 }
957 // Note: Logic for creating and optimizing the ReturnNode is in Compile.
959 // Unlock along the exceptional paths.
960 // This is done late so that we can common up equivalent exceptions
961 // (e.g., null checks) arising from multiple points within this method.
962 // See GraphKit::add_exception_state, which performs the commoning.
963 bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
965 // record exit from a method if compiled while Dtrace is turned on.
966 if (do_synch || C->env()->dtrace_method_probes()) {
967 // First move the exception list out of _exits:
968 GraphKit kit(_exits.transfer_exceptions_into_jvms());
969 SafePointNode* normal_map = kit.map(); // keep this guy safe
970 // Now re-collect the exceptions into _exits:
971 SafePointNode* ex_map;
972 while ((ex_map = kit.pop_exception_state()) != NULL) {
973 Node* ex_oop = kit.use_exception_state(ex_map);
974 // Force the exiting JVM state to have this method at InvocationEntryBci.
975 // The exiting JVM state is otherwise a copy of the calling JVMS.
976 JVMState* caller = kit.jvms();
977 JVMState* ex_jvms = caller->clone_shallow(C);
978 ex_jvms->set_map(kit.clone_map());
979 ex_jvms->map()->set_jvms(ex_jvms);
980 ex_jvms->set_bci( InvocationEntryBci);
981 kit.set_jvms(ex_jvms);
982 if (do_synch) {
983 // Add on the synchronized-method box/object combo
984 kit.map()->push_monitor(_synch_lock);
985 // Unlock!
986 kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
987 }
988 if (C->env()->dtrace_method_probes()) {
989 kit.make_dtrace_method_exit(method());
990 }
991 // Done with exception-path processing.
992 ex_map = kit.make_exception_state(ex_oop);
993 assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
994 // Pop the last vestige of this method:
995 ex_map->set_jvms(caller->clone_shallow(C));
996 ex_map->jvms()->set_map(ex_map);
997 _exits.push_exception_state(ex_map);
998 }
999 assert(_exits.map() == normal_map, "keep the same return state");
1000 }
1002 {
1003 // Capture very early exceptions (receiver null checks) from caller JVMS
1004 GraphKit caller(_caller);
1005 SafePointNode* ex_map;
1006 while ((ex_map = caller.pop_exception_state()) != NULL) {
1007 _exits.add_exception_state(ex_map);
1008 }
1009 }
1010 }
1012 //-----------------------------create_entry_map-------------------------------
1013 // Initialize our parser map to contain the types at method entry.
1014 // For OSR, the map contains a single RawPtr parameter.
1015 // Initial monitor locking for sync. methods is performed by do_method_entry.
1016 SafePointNode* Parse::create_entry_map() {
1017 // Check for really stupid bail-out cases.
1018 uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1019 if (len >= 32760) {
1020 C->record_method_not_compilable_all_tiers("too many local variables");
1021 return NULL;
1022 }
1024 // If this is an inlined method, we may have to do a receiver null check.
1025 if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1026 GraphKit kit(_caller);
1027 kit.null_check_receiver_before_call(method());
1028 _caller = kit.transfer_exceptions_into_jvms();
1029 if (kit.stopped()) {
1030 _exits.add_exception_states_from(_caller);
1031 _exits.set_jvms(_caller);
1032 return NULL;
1033 }
1034 }
1036 assert(method() != NULL, "parser must have a method");
1038 // Create an initial safepoint to hold JVM state during parsing
1039 JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1040 set_map(new (C) SafePointNode(len, jvms));
1041 jvms->set_map(map());
1042 record_for_igvn(map());
1043 assert(jvms->endoff() == len, "correct jvms sizing");
1045 SafePointNode* inmap = _caller->map();
1046 assert(inmap != NULL, "must have inmap");
1048 uint i;
1050 // Pass thru the predefined input parameters.
1051 for (i = 0; i < TypeFunc::Parms; i++) {
1052 map()->init_req(i, inmap->in(i));
1053 }
1055 if (depth() == 1) {
1056 assert(map()->memory()->Opcode() == Op_Parm, "");
1057 // Insert the memory aliasing node
1058 set_all_memory(reset_memory());
1059 }
1060 assert(merged_memory(), "");
1062 // Now add the locals which are initially bound to arguments:
1063 uint arg_size = tf()->domain()->cnt();
1064 ensure_stack(arg_size - TypeFunc::Parms); // OSR methods have funny args
1065 for (i = TypeFunc::Parms; i < arg_size; i++) {
1066 map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1067 }
1069 // Clear out the rest of the map (locals and stack)
1070 for (i = arg_size; i < len; i++) {
1071 map()->init_req(i, top());
1072 }
1074 SafePointNode* entry_map = stop();
1075 return entry_map;
1076 }
1078 //-----------------------------do_method_entry--------------------------------
1079 // Emit any code needed in the pseudo-block before BCI zero.
1080 // The main thing to do is lock the receiver of a synchronized method.
1081 void Parse::do_method_entry() {
1082 set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1083 set_sp(0); // Java Stack Pointer
1085 NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1087 if (C->env()->dtrace_method_probes()) {
1088 make_dtrace_method_entry(method());
1089 }
1091 // If the method is synchronized, we need to construct a lock node, attach
1092 // it to the Start node, and pin it there.
1093 if (method()->is_synchronized()) {
1094 // Insert a FastLockNode right after the Start which takes as arguments
1095 // the current thread pointer, the "this" pointer & the address of the
1096 // stack slot pair used for the lock. The "this" pointer is a projection
1097 // off the start node, but the locking spot has to be constructed by
1098 // creating a ConLNode of 0, and boxing it with a BoxLockNode. The BoxLockNode
1099 // becomes the second argument to the FastLockNode call. The
1100 // FastLockNode becomes the new control parent to pin it to the start.
1102 // Setup Object Pointer
1103 Node *lock_obj = NULL;
1104 if(method()->is_static()) {
1105 ciInstance* mirror = _method->holder()->java_mirror();
1106 const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1107 lock_obj = makecon(t_lock);
1108 } else { // Else pass the "this" pointer,
1109 lock_obj = local(0); // which is Parm0 from StartNode
1110 }
1111 // Clear out dead values from the debug info.
1112 kill_dead_locals();
1113 // Build the FastLockNode
1114 _synch_lock = shared_lock(lock_obj);
1115 }
1117 // Feed profiling data for parameters to the type system so it can
1118 // propagate it as speculative types
1119 record_profiled_parameters_for_speculation();
1121 if (depth() == 1) {
1122 increment_and_test_invocation_counter(Tier2CompileThreshold);
1123 }
1124 }
1126 //------------------------------init_blocks------------------------------------
1127 // Initialize our parser map to contain the types/monitors at method entry.
1128 void Parse::init_blocks() {
1129 // Create the blocks.
1130 _block_count = flow()->block_count();
1131 _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
1132 Copy::zero_to_bytes(_blocks, sizeof(Block)*_block_count);
1134 int rpo;
1136 // Initialize the structs.
1137 for (rpo = 0; rpo < block_count(); rpo++) {
1138 Block* block = rpo_at(rpo);
1139 block->init_node(this, rpo);
1140 }
1142 // Collect predecessor and successor information.
1143 for (rpo = 0; rpo < block_count(); rpo++) {
1144 Block* block = rpo_at(rpo);
1145 block->init_graph(this);
1146 }
1147 }
1149 //-------------------------------init_node-------------------------------------
1150 void Parse::Block::init_node(Parse* outer, int rpo) {
1151 _flow = outer->flow()->rpo_at(rpo);
1152 _pred_count = 0;
1153 _preds_parsed = 0;
1154 _count = 0;
1155 assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
1156 assert(!(is_merged() || is_parsed() || is_handler() || has_merged_backedge()), "sanity");
1157 assert(_live_locals.size() == 0, "sanity");
1159 // entry point has additional predecessor
1160 if (flow()->is_start()) _pred_count++;
1161 assert(flow()->is_start() == (this == outer->start_block()), "");
1162 }
1164 //-------------------------------init_graph------------------------------------
1165 void Parse::Block::init_graph(Parse* outer) {
1166 // Create the successor list for this parser block.
1167 GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
1168 GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
1169 int ns = tfs->length();
1170 int ne = tfe->length();
1171 _num_successors = ns;
1172 _all_successors = ns+ne;
1173 _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
1174 int p = 0;
1175 for (int i = 0; i < ns+ne; i++) {
1176 ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
1177 Block* block2 = outer->rpo_at(tf2->rpo());
1178 _successors[i] = block2;
1180 // Accumulate pred info for the other block, too.
1181 if (i < ns) {
1182 block2->_pred_count++;
1183 } else {
1184 block2->_is_handler = true;
1185 }
1187 #ifdef ASSERT
1188 // A block's successors must be distinguishable by BCI.
1189 // That is, no bytecode is allowed to branch to two different
1190 // clones of the same code location.
1191 for (int j = 0; j < i; j++) {
1192 Block* block1 = _successors[j];
1193 if (block1 == block2) continue; // duplicates are OK
1194 assert(block1->start() != block2->start(), "successors have unique bcis");
1195 }
1196 #endif
1197 }
1199 // Note: We never call next_path_num along exception paths, so they
1200 // never get processed as "ready". Also, the input phis of exception
1201 // handlers get specially processed, so that
1202 }
1204 //---------------------------successor_for_bci---------------------------------
1205 Parse::Block* Parse::Block::successor_for_bci(int bci) {
1206 for (int i = 0; i < all_successors(); i++) {
1207 Block* block2 = successor_at(i);
1208 if (block2->start() == bci) return block2;
1209 }
1210 // We can actually reach here if ciTypeFlow traps out a block
1211 // due to an unloaded class, and concurrently with compilation the
1212 // class is then loaded, so that a later phase of the parser is
1213 // able to see more of the bytecode CFG. Or, the flow pass and
1214 // the parser can have a minor difference of opinion about executability
1215 // of bytecodes. For example, "obj.field = null" is executable even
1216 // if the field's type is an unloaded class; the flow pass used to
1217 // make a trap for such code.
1218 return NULL;
1219 }
1222 //-----------------------------stack_type_at-----------------------------------
1223 const Type* Parse::Block::stack_type_at(int i) const {
1224 return get_type(flow()->stack_type_at(i));
1225 }
1228 //-----------------------------local_type_at-----------------------------------
1229 const Type* Parse::Block::local_type_at(int i) const {
1230 // Make dead locals fall to bottom.
1231 if (_live_locals.size() == 0) {
1232 MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
1233 // This bitmap can be zero length if we saw a breakpoint.
1234 // In such cases, pretend they are all live.
1235 ((Block*)this)->_live_locals = live_locals;
1236 }
1237 if (_live_locals.size() > 0 && !_live_locals.at(i))
1238 return Type::BOTTOM;
1240 return get_type(flow()->local_type_at(i));
1241 }
1244 #ifndef PRODUCT
1246 //----------------------------name_for_bc--------------------------------------
1247 // helper method for BytecodeParseHistogram
1248 static const char* name_for_bc(int i) {
1249 return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
1250 }
1252 //----------------------------BytecodeParseHistogram------------------------------------
1253 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
1254 _parser = p;
1255 _compiler = c;
1256 if( ! _initialized ) { _initialized = true; reset(); }
1257 }
1259 //----------------------------current_count------------------------------------
1260 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
1261 switch( bph_type ) {
1262 case BPH_transforms: { return _parser->gvn().made_progress(); }
1263 case BPH_values: { return _parser->gvn().made_new_values(); }
1264 default: { ShouldNotReachHere(); return 0; }
1265 }
1266 }
1268 //----------------------------initialized--------------------------------------
1269 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
1271 //----------------------------reset--------------------------------------------
1272 void Parse::BytecodeParseHistogram::reset() {
1273 int i = Bytecodes::number_of_codes;
1274 while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
1275 }
1277 //----------------------------set_initial_state--------------------------------
1278 // Record info when starting to parse one bytecode
1279 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
1280 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1281 _initial_bytecode = bc;
1282 _initial_node_count = _compiler->unique();
1283 _initial_transforms = current_count(BPH_transforms);
1284 _initial_values = current_count(BPH_values);
1285 }
1286 }
1288 //----------------------------record_change--------------------------------
1289 // Record results of parsing one bytecode
1290 void Parse::BytecodeParseHistogram::record_change() {
1291 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1292 ++_bytecodes_parsed[_initial_bytecode];
1293 _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
1294 _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
1295 _new_values [_initial_bytecode] += (current_count(BPH_values) - _initial_values);
1296 }
1297 }
1300 //----------------------------print--------------------------------------------
1301 void Parse::BytecodeParseHistogram::print(float cutoff) {
1302 ResourceMark rm;
1303 // print profile
1304 int total = 0;
1305 int i = 0;
1306 for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
1307 int abs_sum = 0;
1308 tty->cr(); //0123456789012345678901234567890123456789012345678901234567890123456789
1309 tty->print_cr("Histogram of %d parsed bytecodes:", total);
1310 if( total == 0 ) { return; }
1311 tty->cr();
1312 tty->print_cr("absolute: count of compiled bytecodes of this type");
1313 tty->print_cr("relative: percentage contribution to compiled nodes");
1314 tty->print_cr("nodes : Average number of nodes constructed per bytecode");
1315 tty->print_cr("rnodes : Significance towards total nodes constructed, (nodes*relative)");
1316 tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
1317 tty->print_cr("values : Average number of node values improved per bytecode");
1318 tty->print_cr("name : Bytecode name");
1319 tty->cr();
1320 tty->print_cr(" absolute relative nodes rnodes transforms values name");
1321 tty->print_cr("----------------------------------------------------------------------");
1322 while (--i > 0) {
1323 int abs = _bytecodes_parsed[i];
1324 float rel = abs * 100.0F / total;
1325 float nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
1326 float rnodes = _bytecodes_parsed[i] == 0 ? 0 : rel * nodes;
1327 float xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
1328 float values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values [i])/_bytecodes_parsed[i];
1329 if (cutoff <= rel) {
1330 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));
1331 abs_sum += abs;
1332 }
1333 }
1334 tty->print_cr("----------------------------------------------------------------------");
1335 float rel_sum = abs_sum * 100.0F / total;
1336 tty->print_cr("%10d %7.2f%% (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
1337 tty->print_cr("----------------------------------------------------------------------");
1338 tty->cr();
1339 }
1340 #endif
1342 //----------------------------load_state_from----------------------------------
1343 // Load block/map/sp. But not do not touch iter/bci.
1344 void Parse::load_state_from(Block* block) {
1345 set_block(block);
1346 // load the block's JVM state:
1347 set_map(block->start_map());
1348 set_sp( block->start_sp());
1349 }
1352 //-----------------------------record_state------------------------------------
1353 void Parse::Block::record_state(Parse* p) {
1354 assert(!is_merged(), "can only record state once, on 1st inflow");
1355 assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
1356 set_start_map(p->stop());
1357 }
1360 //------------------------------do_one_block-----------------------------------
1361 void Parse::do_one_block() {
1362 if (TraceOptoParse) {
1363 Block *b = block();
1364 int ns = b->num_successors();
1365 int nt = b->all_successors();
1367 tty->print("Parsing block #%d at bci [%d,%d), successors: ",
1368 block()->rpo(), block()->start(), block()->limit());
1369 for (int i = 0; i < nt; i++) {
1370 tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
1371 }
1372 if (b->is_loop_head()) tty->print(" lphd");
1373 tty->cr();
1374 }
1376 assert(block()->is_merged(), "must be merged before being parsed");
1377 block()->mark_parsed();
1378 ++_blocks_parsed;
1380 // Set iterator to start of block.
1381 iter().reset_to_bci(block()->start());
1383 CompileLog* log = C->log();
1385 // Parse bytecodes
1386 while (!stopped() && !failing()) {
1387 iter().next();
1389 // Learn the current bci from the iterator:
1390 set_parse_bci(iter().cur_bci());
1392 if (bci() == block()->limit()) {
1393 // Do not walk into the next block until directed by do_all_blocks.
1394 merge(bci());
1395 break;
1396 }
1397 assert(bci() < block()->limit(), "bci still in block");
1399 if (log != NULL) {
1400 // Output an optional context marker, to help place actions
1401 // that occur during parsing of this BC. If there is no log
1402 // output until the next context string, this context string
1403 // will be silently ignored.
1404 log->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
1405 }
1407 if (block()->has_trap_at(bci())) {
1408 // We must respect the flow pass's traps, because it will refuse
1409 // to produce successors for trapping blocks.
1410 int trap_index = block()->flow()->trap_index();
1411 assert(trap_index != 0, "trap index must be valid");
1412 uncommon_trap(trap_index);
1413 break;
1414 }
1416 NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1418 #ifdef ASSERT
1419 int pre_bc_sp = sp();
1420 int inputs, depth;
1421 bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1422 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));
1423 #endif //ASSERT
1425 do_one_bytecode();
1427 assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
1428 err_msg_res("incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth));
1430 do_exceptions();
1432 NOT_PRODUCT( parse_histogram()->record_change(); );
1434 if (log != NULL)
1435 log->clear_context(); // skip marker if nothing was printed
1437 // Fall into next bytecode. Each bytecode normally has 1 sequential
1438 // successor which is typically made ready by visiting this bytecode.
1439 // If the successor has several predecessors, then it is a merge
1440 // point, starts a new basic block, and is handled like other basic blocks.
1441 }
1442 }
1445 //------------------------------merge------------------------------------------
1446 void Parse::set_parse_bci(int bci) {
1447 set_bci(bci);
1448 Node_Notes* nn = C->default_node_notes();
1449 if (nn == NULL) return;
1451 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
1452 if (!DebugInlinedCalls && depth() > 1) {
1453 return;
1454 }
1456 // Update the JVMS annotation, if present.
1457 JVMState* jvms = nn->jvms();
1458 if (jvms != NULL && jvms->bci() != bci) {
1459 // Update the JVMS.
1460 jvms = jvms->clone_shallow(C);
1461 jvms->set_bci(bci);
1462 nn->set_jvms(jvms);
1463 }
1464 }
1466 //------------------------------merge------------------------------------------
1467 // Merge the current mapping into the basic block starting at bci
1468 void Parse::merge(int target_bci) {
1469 Block* target = successor_for_bci(target_bci);
1470 if (target == NULL) { handle_missing_successor(target_bci); return; }
1471 assert(!target->is_ready(), "our arrival must be expected");
1472 int pnum = target->next_path_num();
1473 merge_common(target, pnum);
1474 }
1476 //-------------------------merge_new_path--------------------------------------
1477 // Merge the current mapping into the basic block, using a new path
1478 void Parse::merge_new_path(int target_bci) {
1479 Block* target = successor_for_bci(target_bci);
1480 if (target == NULL) { handle_missing_successor(target_bci); return; }
1481 assert(!target->is_ready(), "new path into frozen graph");
1482 int pnum = target->add_new_path();
1483 merge_common(target, pnum);
1484 }
1486 //-------------------------merge_exception-------------------------------------
1487 // Merge the current mapping into the basic block starting at bci
1488 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
1489 void Parse::merge_exception(int target_bci) {
1490 assert(sp() == 1, "must have only the throw exception on the stack");
1491 Block* target = successor_for_bci(target_bci);
1492 if (target == NULL) { handle_missing_successor(target_bci); return; }
1493 assert(target->is_handler(), "exceptions are handled by special blocks");
1494 int pnum = target->add_new_path();
1495 merge_common(target, pnum);
1496 }
1498 //--------------------handle_missing_successor---------------------------------
1499 void Parse::handle_missing_successor(int target_bci) {
1500 #ifndef PRODUCT
1501 Block* b = block();
1502 int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1503 tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1504 #endif
1505 ShouldNotReachHere();
1506 }
1508 //--------------------------merge_common---------------------------------------
1509 void Parse::merge_common(Parse::Block* target, int pnum) {
1510 if (TraceOptoParse) {
1511 tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1512 }
1514 // Zap extra stack slots to top
1515 assert(sp() == target->start_sp(), "");
1516 clean_stack(sp());
1518 if (!target->is_merged()) { // No prior mapping at this bci
1519 if (TraceOptoParse) { tty->print(" with empty state"); }
1521 // If this path is dead, do not bother capturing it as a merge.
1522 // It is "as if" we had 1 fewer predecessors from the beginning.
1523 if (stopped()) {
1524 if (TraceOptoParse) tty->print_cr(", but path is dead and doesn't count");
1525 return;
1526 }
1528 // Record that a new block has been merged.
1529 ++_blocks_merged;
1531 // Make a region if we know there are multiple or unpredictable inputs.
1532 // (Also, if this is a plain fall-through, we might see another region,
1533 // which must not be allowed into this block's map.)
1534 if (pnum > PhiNode::Input // Known multiple inputs.
1535 || target->is_handler() // These have unpredictable inputs.
1536 || target->is_loop_head() // Known multiple inputs
1537 || control()->is_Region()) { // We must hide this guy.
1539 int current_bci = bci();
1540 set_parse_bci(target->start()); // Set target bci
1541 if (target->is_SEL_head()) {
1542 DEBUG_ONLY( target->mark_merged_backedge(block()); )
1543 if (target->start() == 0) {
1544 // Add loop predicate for the special case when
1545 // there are backbranches to the method entry.
1546 add_predicate();
1547 }
1548 }
1549 // Add a Region to start the new basic block. Phis will be added
1550 // later lazily.
1551 int edges = target->pred_count();
1552 if (edges < pnum) edges = pnum; // might be a new path!
1553 RegionNode *r = new (C) RegionNode(edges+1);
1554 gvn().set_type(r, Type::CONTROL);
1555 record_for_igvn(r);
1556 // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1557 // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1558 r->init_req(pnum, control());
1559 set_control(r);
1560 set_parse_bci(current_bci); // Restore bci
1561 }
1563 // Convert the existing Parser mapping into a mapping at this bci.
1564 store_state_to(target);
1565 assert(target->is_merged(), "do not come here twice");
1567 } else { // Prior mapping at this bci
1568 if (TraceOptoParse) { tty->print(" with previous state"); }
1569 #ifdef ASSERT
1570 if (target->is_SEL_head()) {
1571 target->mark_merged_backedge(block());
1572 }
1573 #endif
1574 // We must not manufacture more phis if the target is already parsed.
1575 bool nophi = target->is_parsed();
1577 SafePointNode* newin = map();// Hang on to incoming mapping
1578 Block* save_block = block(); // Hang on to incoming block;
1579 load_state_from(target); // Get prior mapping
1581 assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1582 assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1583 assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1584 assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1586 // Iterate over my current mapping and the old mapping.
1587 // Where different, insert Phi functions.
1588 // Use any existing Phi functions.
1589 assert(control()->is_Region(), "must be merging to a region");
1590 RegionNode* r = control()->as_Region();
1592 // Compute where to merge into
1593 // Merge incoming control path
1594 r->init_req(pnum, newin->control());
1596 if (pnum == 1) { // Last merge for this Region?
1597 if (!block()->flow()->is_irreducible_entry()) {
1598 Node* result = _gvn.transform_no_reclaim(r);
1599 if (r != result && TraceOptoParse) {
1600 tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1601 }
1602 }
1603 record_for_igvn(r);
1604 }
1606 // Update all the non-control inputs to map:
1607 assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1608 bool check_elide_phi = target->is_SEL_backedge(save_block);
1609 for (uint j = 1; j < newin->req(); j++) {
1610 Node* m = map()->in(j); // Current state of target.
1611 Node* n = newin->in(j); // Incoming change to target state.
1612 PhiNode* phi;
1613 if (m->is_Phi() && m->as_Phi()->region() == r)
1614 phi = m->as_Phi();
1615 else
1616 phi = NULL;
1617 if (m != n) { // Different; must merge
1618 switch (j) {
1619 // Frame pointer and Return Address never changes
1620 case TypeFunc::FramePtr:// Drop m, use the original value
1621 case TypeFunc::ReturnAdr:
1622 break;
1623 case TypeFunc::Memory: // Merge inputs to the MergeMem node
1624 assert(phi == NULL, "the merge contains phis, not vice versa");
1625 merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1626 continue;
1627 default: // All normal stuff
1628 if (phi == NULL) {
1629 const JVMState* jvms = map()->jvms();
1630 if (EliminateNestedLocks &&
1631 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1632 // BoxLock nodes are not commoning.
1633 // Use old BoxLock node as merged box.
1634 assert(newin->jvms()->is_monitor_box(j), "sanity");
1635 // This assert also tests that nodes are BoxLock.
1636 assert(BoxLockNode::same_slot(n, m), "sanity");
1637 C->gvn_replace_by(n, m);
1638 } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1639 phi = ensure_phi(j, nophi);
1640 }
1641 }
1642 break;
1643 }
1644 }
1645 // At this point, n might be top if:
1646 // - there is no phi (because TypeFlow detected a conflict), or
1647 // - the corresponding control edges is top (a dead incoming path)
1648 // It is a bug if we create a phi which sees a garbage value on a live path.
1650 if (phi != NULL) {
1651 assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1652 assert(phi->region() == r, "");
1653 phi->set_req(pnum, n); // Then add 'n' to the merge
1654 if (pnum == PhiNode::Input) {
1655 // Last merge for this Phi.
1656 // So far, Phis have had a reasonable type from ciTypeFlow.
1657 // Now _gvn will join that with the meet of current inputs.
1658 // BOTTOM is never permissible here, 'cause pessimistically
1659 // Phis of pointers cannot lose the basic pointer type.
1660 debug_only(const Type* bt1 = phi->bottom_type());
1661 assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1662 map()->set_req(j, _gvn.transform_no_reclaim(phi));
1663 debug_only(const Type* bt2 = phi->bottom_type());
1664 assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
1665 record_for_igvn(phi);
1666 }
1667 }
1668 } // End of for all values to be merged
1670 if (pnum == PhiNode::Input &&
1671 !r->in(0)) { // The occasional useless Region
1672 assert(control() == r, "");
1673 set_control(r->nonnull_req());
1674 }
1676 // newin has been subsumed into the lazy merge, and is now dead.
1677 set_block(save_block);
1679 stop(); // done with this guy, for now
1680 }
1682 if (TraceOptoParse) {
1683 tty->print_cr(" on path %d", pnum);
1684 }
1686 // Done with this parser state.
1687 assert(stopped(), "");
1688 }
1691 //--------------------------merge_memory_edges---------------------------------
1692 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1693 // (nophi means we must not create phis, because we already parsed here)
1694 assert(n != NULL, "");
1695 // Merge the inputs to the MergeMems
1696 MergeMemNode* m = merged_memory();
1698 assert(control()->is_Region(), "must be merging to a region");
1699 RegionNode* r = control()->as_Region();
1701 PhiNode* base = NULL;
1702 MergeMemNode* remerge = NULL;
1703 for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1704 Node *p = mms.force_memory();
1705 Node *q = mms.memory2();
1706 if (mms.is_empty() && nophi) {
1707 // Trouble: No new splits allowed after a loop body is parsed.
1708 // Instead, wire the new split into a MergeMem on the backedge.
1709 // The optimizer will sort it out, slicing the phi.
1710 if (remerge == NULL) {
1711 assert(base != NULL, "");
1712 assert(base->in(0) != NULL, "should not be xformed away");
1713 remerge = MergeMemNode::make(C, base->in(pnum));
1714 gvn().set_type(remerge, Type::MEMORY);
1715 base->set_req(pnum, remerge);
1716 }
1717 remerge->set_memory_at(mms.alias_idx(), q);
1718 continue;
1719 }
1720 assert(!q->is_MergeMem(), "");
1721 PhiNode* phi;
1722 if (p != q) {
1723 phi = ensure_memory_phi(mms.alias_idx(), nophi);
1724 } else {
1725 if (p->is_Phi() && p->as_Phi()->region() == r)
1726 phi = p->as_Phi();
1727 else
1728 phi = NULL;
1729 }
1730 // Insert q into local phi
1731 if (phi != NULL) {
1732 assert(phi->region() == r, "");
1733 p = phi;
1734 phi->set_req(pnum, q);
1735 if (mms.at_base_memory()) {
1736 base = phi; // delay transforming it
1737 } else if (pnum == 1) {
1738 record_for_igvn(phi);
1739 p = _gvn.transform_no_reclaim(phi);
1740 }
1741 mms.set_memory(p);// store back through the iterator
1742 }
1743 }
1744 // Transform base last, in case we must fiddle with remerging.
1745 if (base != NULL && pnum == 1) {
1746 record_for_igvn(base);
1747 m->set_base_memory( _gvn.transform_no_reclaim(base) );
1748 }
1749 }
1752 //------------------------ensure_phis_everywhere-------------------------------
1753 void Parse::ensure_phis_everywhere() {
1754 ensure_phi(TypeFunc::I_O);
1756 // Ensure a phi on all currently known memories.
1757 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
1758 ensure_memory_phi(mms.alias_idx());
1759 debug_only(mms.set_memory()); // keep the iterator happy
1760 }
1762 // Note: This is our only chance to create phis for memory slices.
1763 // If we miss a slice that crops up later, it will have to be
1764 // merged into the base-memory phi that we are building here.
1765 // Later, the optimizer will comb out the knot, and build separate
1766 // phi-loops for each memory slice that matters.
1768 // Monitors must nest nicely and not get confused amongst themselves.
1769 // Phi-ify everything up to the monitors, though.
1770 uint monoff = map()->jvms()->monoff();
1771 uint nof_monitors = map()->jvms()->nof_monitors();
1773 assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
1774 bool check_elide_phi = block()->is_SEL_head();
1775 for (uint i = TypeFunc::Parms; i < monoff; i++) {
1776 if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
1777 ensure_phi(i);
1778 }
1779 }
1781 // Even monitors need Phis, though they are well-structured.
1782 // This is true for OSR methods, and also for the rare cases where
1783 // a monitor object is the subject of a replace_in_map operation.
1784 // See bugs 4426707 and 5043395.
1785 for (uint m = 0; m < nof_monitors; m++) {
1786 ensure_phi(map()->jvms()->monitor_obj_offset(m));
1787 }
1788 }
1791 //-----------------------------add_new_path------------------------------------
1792 // Add a previously unaccounted predecessor to this block.
1793 int Parse::Block::add_new_path() {
1794 // If there is no map, return the lowest unused path number.
1795 if (!is_merged()) return pred_count()+1; // there will be a map shortly
1797 SafePointNode* map = start_map();
1798 if (!map->control()->is_Region())
1799 return pred_count()+1; // there may be a region some day
1800 RegionNode* r = map->control()->as_Region();
1802 // Add new path to the region.
1803 uint pnum = r->req();
1804 r->add_req(NULL);
1806 for (uint i = 1; i < map->req(); i++) {
1807 Node* n = map->in(i);
1808 if (i == TypeFunc::Memory) {
1809 // Ensure a phi on all currently known memories.
1810 for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1811 Node* phi = mms.memory();
1812 if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1813 assert(phi->req() == pnum, "must be same size as region");
1814 phi->add_req(NULL);
1815 }
1816 }
1817 } else {
1818 if (n->is_Phi() && n->as_Phi()->region() == r) {
1819 assert(n->req() == pnum, "must be same size as region");
1820 n->add_req(NULL);
1821 }
1822 }
1823 }
1825 return pnum;
1826 }
1828 //------------------------------ensure_phi-------------------------------------
1829 // Turn the idx'th entry of the current map into a Phi
1830 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
1831 SafePointNode* map = this->map();
1832 Node* region = map->control();
1833 assert(region->is_Region(), "");
1835 Node* o = map->in(idx);
1836 assert(o != NULL, "");
1838 if (o == top()) return NULL; // TOP always merges into TOP
1840 if (o->is_Phi() && o->as_Phi()->region() == region) {
1841 return o->as_Phi();
1842 }
1844 // Now use a Phi here for merging
1845 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1846 const JVMState* jvms = map->jvms();
1847 const Type* t;
1848 if (jvms->is_loc(idx)) {
1849 t = block()->local_type_at(idx - jvms->locoff());
1850 } else if (jvms->is_stk(idx)) {
1851 t = block()->stack_type_at(idx - jvms->stkoff());
1852 } else if (jvms->is_mon(idx)) {
1853 assert(!jvms->is_monitor_box(idx), "no phis for boxes");
1854 t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
1855 } else if ((uint)idx < TypeFunc::Parms) {
1856 t = o->bottom_type(); // Type::RETURN_ADDRESS or such-like.
1857 } else {
1858 assert(false, "no type information for this phi");
1859 }
1861 // If the type falls to bottom, then this must be a local that
1862 // is mixing ints and oops or some such. Forcing it to top
1863 // makes it go dead.
1864 if (t == Type::BOTTOM) {
1865 map->set_req(idx, top());
1866 return NULL;
1867 }
1869 // Do not create phis for top either.
1870 // A top on a non-null control flow must be an unused even after the.phi.
1871 if (t == Type::TOP || t == Type::HALF) {
1872 map->set_req(idx, top());
1873 return NULL;
1874 }
1876 PhiNode* phi = PhiNode::make(region, o, t);
1877 gvn().set_type(phi, t);
1878 if (C->do_escape_analysis()) record_for_igvn(phi);
1879 map->set_req(idx, phi);
1880 return phi;
1881 }
1883 //--------------------------ensure_memory_phi----------------------------------
1884 // Turn the idx'th slice of the current memory into a Phi
1885 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
1886 MergeMemNode* mem = merged_memory();
1887 Node* region = control();
1888 assert(region->is_Region(), "");
1890 Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
1891 assert(o != NULL && o != top(), "");
1893 PhiNode* phi;
1894 if (o->is_Phi() && o->as_Phi()->region() == region) {
1895 phi = o->as_Phi();
1896 if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
1897 // clone the shared base memory phi to make a new memory split
1898 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1899 const Type* t = phi->bottom_type();
1900 const TypePtr* adr_type = C->get_adr_type(idx);
1901 phi = phi->slice_memory(adr_type);
1902 gvn().set_type(phi, t);
1903 }
1904 return phi;
1905 }
1907 // Now use a Phi here for merging
1908 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1909 const Type* t = o->bottom_type();
1910 const TypePtr* adr_type = C->get_adr_type(idx);
1911 phi = PhiNode::make(region, o, t, adr_type);
1912 gvn().set_type(phi, t);
1913 if (idx == Compile::AliasIdxBot)
1914 mem->set_base_memory(phi);
1915 else
1916 mem->set_memory_at(idx, phi);
1917 return phi;
1918 }
1920 //------------------------------call_register_finalizer-----------------------
1921 // Check the klass of the receiver and call register_finalizer if the
1922 // class need finalization.
1923 void Parse::call_register_finalizer() {
1924 Node* receiver = local(0);
1925 assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
1926 "must have non-null instance type");
1928 const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
1929 if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
1930 // The type isn't known exactly so see if CHA tells us anything.
1931 ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
1932 if (!Dependencies::has_finalizable_subclass(ik)) {
1933 // No finalizable subclasses so skip the dynamic check.
1934 C->dependencies()->assert_has_no_finalizable_subclasses(ik);
1935 return;
1936 }
1937 }
1939 // Insert a dynamic test for whether the instance needs
1940 // finalization. In general this will fold up since the concrete
1941 // class is often visible so the access flags are constant.
1942 Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
1943 Node* klass = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), klass_addr, TypeInstPtr::KLASS) );
1945 Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
1946 Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT, MemNode::unordered);
1948 Node* mask = _gvn.transform(new (C) AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
1949 Node* check = _gvn.transform(new (C) CmpINode(mask, intcon(0)));
1950 Node* test = _gvn.transform(new (C) BoolNode(check, BoolTest::ne));
1952 IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
1954 RegionNode* result_rgn = new (C) RegionNode(3);
1955 record_for_igvn(result_rgn);
1957 Node *skip_register = _gvn.transform(new (C) IfFalseNode(iff));
1958 result_rgn->init_req(1, skip_register);
1960 Node *needs_register = _gvn.transform(new (C) IfTrueNode(iff));
1961 set_control(needs_register);
1962 if (stopped()) {
1963 // There is no slow path.
1964 result_rgn->init_req(2, top());
1965 } else {
1966 Node *call = make_runtime_call(RC_NO_LEAF,
1967 OptoRuntime::register_finalizer_Type(),
1968 OptoRuntime::register_finalizer_Java(),
1969 NULL, TypePtr::BOTTOM,
1970 receiver);
1971 make_slow_call_ex(call, env()->Throwable_klass(), true);
1973 Node* fast_io = call->in(TypeFunc::I_O);
1974 Node* fast_mem = call->in(TypeFunc::Memory);
1975 // These two phis are pre-filled with copies of of the fast IO and Memory
1976 Node* io_phi = PhiNode::make(result_rgn, fast_io, Type::ABIO);
1977 Node* mem_phi = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
1979 result_rgn->init_req(2, control());
1980 io_phi ->init_req(2, i_o());
1981 mem_phi ->init_req(2, reset_memory());
1983 set_all_memory( _gvn.transform(mem_phi) );
1984 set_i_o( _gvn.transform(io_phi) );
1985 }
1987 set_control( _gvn.transform(result_rgn) );
1988 }
1990 // Add check to deoptimize if RTM state is not ProfileRTM
1991 void Parse::rtm_deopt() {
1992 #if INCLUDE_RTM_OPT
1993 if (C->profile_rtm()) {
1994 assert(C->method() != NULL, "only for normal compilations");
1995 assert(!C->method()->method_data()->is_empty(), "MDO is needed to record RTM state");
1996 assert(depth() == 1, "generate check only for main compiled method");
1998 // Set starting bci for uncommon trap.
1999 set_parse_bci(is_osr_parse() ? osr_bci() : 0);
2001 // Load the rtm_state from the MethodData.
2002 const TypePtr* adr_type = TypeMetadataPtr::make(C->method()->method_data());
2003 Node* mdo = makecon(adr_type);
2004 int offset = MethodData::rtm_state_offset_in_bytes();
2005 Node* adr_node = basic_plus_adr(mdo, mdo, offset);
2006 Node* rtm_state = make_load(control(), adr_node, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2008 // Separate Load from Cmp by Opaque.
2009 // In expand_macro_nodes() it will be replaced either
2010 // with this load when there are locks in the code
2011 // or with ProfileRTM (cmp->in(2)) otherwise so that
2012 // the check will fold.
2013 Node* profile_state = makecon(TypeInt::make(ProfileRTM));
2014 Node* opq = _gvn.transform( new (C) Opaque3Node(C, rtm_state, Opaque3Node::RTM_OPT) );
2015 Node* chk = _gvn.transform( new (C) CmpINode(opq, profile_state) );
2016 Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
2017 // Branch to failure if state was changed
2018 { BuildCutout unless(this, tst, PROB_ALWAYS);
2019 uncommon_trap(Deoptimization::Reason_rtm_state_change,
2020 Deoptimization::Action_make_not_entrant);
2021 }
2022 }
2023 #endif
2024 }
2026 //------------------------------return_current---------------------------------
2027 // Append current _map to _exit_return
2028 void Parse::return_current(Node* value) {
2029 if (RegisterFinalizersAtInit &&
2030 method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2031 call_register_finalizer();
2032 }
2034 // Do not set_parse_bci, so that return goo is credited to the return insn.
2035 set_bci(InvocationEntryBci);
2036 if (method()->is_synchronized() && GenerateSynchronizationCode) {
2037 shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2038 }
2039 if (C->env()->dtrace_method_probes()) {
2040 make_dtrace_method_exit(method());
2041 }
2042 SafePointNode* exit_return = _exits.map();
2043 exit_return->in( TypeFunc::Control )->add_req( control() );
2044 exit_return->in( TypeFunc::I_O )->add_req( i_o () );
2045 Node *mem = exit_return->in( TypeFunc::Memory );
2046 for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2047 if (mms.is_empty()) {
2048 // get a copy of the base memory, and patch just this one input
2049 const TypePtr* adr_type = mms.adr_type(C);
2050 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2051 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2052 gvn().set_type_bottom(phi);
2053 phi->del_req(phi->req()-1); // prepare to re-patch
2054 mms.set_memory(phi);
2055 }
2056 mms.memory()->add_req(mms.memory2());
2057 }
2059 // frame pointer is always same, already captured
2060 if (value != NULL) {
2061 // If returning oops to an interface-return, there is a silent free
2062 // cast from oop to interface allowed by the Verifier. Make it explicit
2063 // here.
2064 Node* phi = _exits.argument(0);
2065 const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
2066 if( tr && tr->klass()->is_loaded() &&
2067 tr->klass()->is_interface() ) {
2068 const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
2069 if (tp && tp->klass()->is_loaded() &&
2070 !tp->klass()->is_interface()) {
2071 // sharpen the type eagerly; this eases certain assert checking
2072 if (tp->higher_equal(TypeInstPtr::NOTNULL))
2073 tr = tr->join_speculative(TypeInstPtr::NOTNULL)->is_instptr();
2074 value = _gvn.transform(new (C) CheckCastPPNode(0,value,tr));
2075 }
2076 }
2077 phi->add_req(value);
2078 }
2080 stop_and_kill_map(); // This CFG path dies here
2081 }
2084 //------------------------------add_safepoint----------------------------------
2085 void Parse::add_safepoint() {
2086 // See if we can avoid this safepoint. No need for a SafePoint immediately
2087 // after a Call (except Leaf Call) or another SafePoint.
2088 Node *proj = control();
2089 bool add_poll_param = SafePointNode::needs_polling_address_input();
2090 uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2091 if( proj->is_Proj() ) {
2092 Node *n0 = proj->in(0);
2093 if( n0->is_Catch() ) {
2094 n0 = n0->in(0)->in(0);
2095 assert( n0->is_Call(), "expect a call here" );
2096 }
2097 if( n0->is_Call() ) {
2098 if( n0->as_Call()->guaranteed_safepoint() )
2099 return;
2100 } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2101 return;
2102 }
2103 }
2105 // Clear out dead values from the debug info.
2106 kill_dead_locals();
2108 // Clone the JVM State
2109 SafePointNode *sfpnt = new (C) SafePointNode(parms, NULL);
2111 // Capture memory state BEFORE a SafePoint. Since we can block at a
2112 // SafePoint we need our GC state to be safe; i.e. we need all our current
2113 // write barriers (card marks) to not float down after the SafePoint so we
2114 // must read raw memory. Likewise we need all oop stores to match the card
2115 // marks. If deopt can happen, we need ALL stores (we need the correct JVM
2116 // state on a deopt).
2118 // We do not need to WRITE the memory state after a SafePoint. The control
2119 // edge will keep card-marks and oop-stores from floating up from below a
2120 // SafePoint and our true dependency added here will keep them from floating
2121 // down below a SafePoint.
2123 // Clone the current memory state
2124 Node* mem = MergeMemNode::make(C, map()->memory());
2126 mem = _gvn.transform(mem);
2128 // Pass control through the safepoint
2129 sfpnt->init_req(TypeFunc::Control , control());
2130 // Fix edges normally used by a call
2131 sfpnt->init_req(TypeFunc::I_O , top() );
2132 sfpnt->init_req(TypeFunc::Memory , mem );
2133 sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2134 sfpnt->init_req(TypeFunc::FramePtr , top() );
2136 // Create a node for the polling address
2137 if( add_poll_param ) {
2138 Node *polladr = ConPNode::make(C, (address)os::get_polling_page());
2139 sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2140 }
2142 // Fix up the JVM State edges
2143 add_safepoint_edges(sfpnt);
2144 Node *transformed_sfpnt = _gvn.transform(sfpnt);
2145 set_control(transformed_sfpnt);
2147 // Provide an edge from root to safepoint. This makes the safepoint
2148 // appear useful until the parse has completed.
2149 if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2150 assert(C->root() != NULL, "Expect parse is still valid");
2151 C->root()->add_prec(transformed_sfpnt);
2152 }
2153 }
2155 #ifndef PRODUCT
2156 //------------------------show_parse_info--------------------------------------
2157 void Parse::show_parse_info() {
2158 InlineTree* ilt = NULL;
2159 if (C->ilt() != NULL) {
2160 JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2161 ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2162 }
2163 if (PrintCompilation && Verbose) {
2164 if (depth() == 1) {
2165 if( ilt->count_inlines() ) {
2166 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2167 ilt->count_inline_bcs());
2168 tty->cr();
2169 }
2170 } else {
2171 if (method()->is_synchronized()) tty->print("s");
2172 if (method()->has_exception_handlers()) tty->print("!");
2173 // Check this is not the final compiled version
2174 if (C->trap_can_recompile()) {
2175 tty->print("-");
2176 } else {
2177 tty->print(" ");
2178 }
2179 method()->print_short_name();
2180 if (is_osr_parse()) {
2181 tty->print(" @ %d", osr_bci());
2182 }
2183 tty->print(" (%d bytes)",method()->code_size());
2184 if (ilt->count_inlines()) {
2185 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2186 ilt->count_inline_bcs());
2187 }
2188 tty->cr();
2189 }
2190 }
2191 if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2192 // Print that we succeeded; suppress this message on the first osr parse.
2194 if (method()->is_synchronized()) tty->print("s");
2195 if (method()->has_exception_handlers()) tty->print("!");
2196 // Check this is not the final compiled version
2197 if (C->trap_can_recompile() && depth() == 1) {
2198 tty->print("-");
2199 } else {
2200 tty->print(" ");
2201 }
2202 if( depth() != 1 ) { tty->print(" "); } // missing compile count
2203 for (int i = 1; i < depth(); ++i) { tty->print(" "); }
2204 method()->print_short_name();
2205 if (is_osr_parse()) {
2206 tty->print(" @ %d", osr_bci());
2207 }
2208 if (ilt->caller_bci() != -1) {
2209 tty->print(" @ %d", ilt->caller_bci());
2210 }
2211 tty->print(" (%d bytes)",method()->code_size());
2212 if (ilt->count_inlines()) {
2213 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2214 ilt->count_inline_bcs());
2215 }
2216 tty->cr();
2217 }
2218 }
2221 //------------------------------dump-------------------------------------------
2222 // Dump information associated with the bytecodes of current _method
2223 void Parse::dump() {
2224 if( method() != NULL ) {
2225 // Iterate over bytecodes
2226 ciBytecodeStream iter(method());
2227 for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2228 dump_bci( iter.cur_bci() );
2229 tty->cr();
2230 }
2231 }
2232 }
2234 // Dump information associated with a byte code index, 'bci'
2235 void Parse::dump_bci(int bci) {
2236 // Output info on merge-points, cloning, and within _jsr..._ret
2237 // NYI
2238 tty->print(" bci:%d", bci);
2239 }
2241 #endif